JP5637161B2 - Method for producing weather-resistant coating composition, method for preventing coloring, and coated article - Google Patents

Description

  The present invention relates to a vinyl polymer in which a hydrolyzable silyl group and an organic ultraviolet absorbing group are bonded to side chains, silica fine particles, an organic solvent containing a carbonyl group, an orthocarboxylic acid ester, and a tertiary amine or its A method for producing a weather-resistant coating composition containing an organic acid salt, a method for preventing coloration of the composition, a coating composition produced by this method on a substrate, and coating the cured coating layer with silicon. The present invention relates to a coated article formed by laminating oxide-containing hard coatings.

  In recent years, as a substitute for transparent plate glass, it has been widely used to use a transparent material that is non-crushable or has a higher resistance to crushing than glass. For example, plastic substrates, especially polycarbonate resin, etc. are excellent in transparency, impact resistance, heat resistance, etc., so they can be used for various applications such as windows for buildings and vehicles, instrument covers, etc. as structural members that replace glass. Currently used.

  However, since it is inferior to glass in terms of surface properties such as scratch resistance and weather resistance, it has been eagerly desired to improve the surface properties of polycarbonate resin molded products. Recently, it has been used for vehicle windows, sound insulation walls for roads, etc. There is a demand for something that can withstand outdoor exposure for more than 10 years.

  As a means for improving the weather resistance of the polycarbonate resin molded article, a method of laminating an acrylic resin film having excellent weather resistance on the surface of the polycarbonate resin base material or a UV absorber was contained on the resin surface by coextrusion or the like. A method of providing a resin layer has been proposed.

  In addition, as a method for improving the scratch resistance of a polycarbonate resin molded product, there are a method of coating a thermosetting resin such as polyorganosiloxane and melamine, and a method of coating a polyfunctional acrylic photocurable resin. Proposed.

  On the other hand, methods for producing a transparent body having both weather resistance and scratch resistance are described in JP-A-56-92059, JP-A-1-149878 (Patent Documents 1 and 2), and the like. An ultraviolet-absorbing transparent substrate is known in which a protective coating of a colloidal silica-containing polysiloxane paint is provided via an undercoat layer to which an ultraviolet absorber is added.

  However, the addition of a large amount of UV absorber to the undercoat layer deteriorates the adhesion with the protective coating by the colloidal silica-containing polysiloxane paint applied to the upper surface of the base material or the undercoat layer, or during the heat curing step, For example, if it is removed from the composition by volatilization, or if it is used outdoors for a long period of time, the ultraviolet absorber gradually bleeds out, causing cracks, whitening or yellowing. It was. Further, the protective coating layer made of colloidal silica-containing polysiloxane on the upper surface has a problem that a large amount of an ultraviolet absorber cannot be added from the viewpoint of scratch resistance.

  Also, a benzotriazole-based UV-absorbing vinyl monomer or a benzophenone-based UV-absorbing vinyl monomer, an alkoxysilyl group-containing vinyl monomer, and a vinyl monomer copolymerizable with these monomers, It is known that a multilayer laminated resin article imparted with weather resistance while maintaining adhesion to a resin substrate can be obtained by using a copolymer of the above as a coating component [Japanese Patent Laid-Open No. 2001-114841 and Patents] No. 3102696, JP-A-2001-214122, JP-A-2001-47574 (Patent Documents 3 to 6)].

  These use a copolymer-containing coating as an undercoat and form a colloidal silica-containing polysiloxane resin coating on the coating to obtain a coated article imparted with scratch resistance and weather resistance. For these, the adhesion to the polysiloxane resin film and the weather resistance are considerably improved, but the cross-linking network of the alkoxysilyl group of the undercoat layer does not proceed sufficiently, so that the uncured residual alkoxysilyl group or hydroxysilyl group Since post-crosslinking occurred over time and the film was apt to be distorted, defects such as cracks and peeling were likely to occur, and it was still insufficient for long-term weather resistance. Furthermore, when the coating film is exposed to a rapid change in ambient temperature, particularly a change at a relatively high temperature, there is a drawback that cracks due to post-crosslinking are likely to occur.

The present inventor has disclosed a primer comprising an ultraviolet-absorbing vinyl monomer, an alkoxysilyl group-containing vinyl monomer, a copolymer of vinyl monomers copolymerizable with these monomers, and silica fine particles. A composition has been proposed [Japanese Patent Laid-Open No. 2008-120986 (Patent Document 7)]. The film obtained by applying and curing the primer composition is a hydrolyzable silyl group and / or SiOH group of the vinyl polymer, or a hydrolyzable silyl group and / or SiOH group of the vinyl polymer. Due to the dense three-dimensional cross-linking network formed by siloxane cross-linking between the silica fine particles and the SiOH groups on the surface of the silica fine particles, and the low expansive action of the silica fine particles themselves, the linear expansion coefficient becomes low, and the expansion / contraction due to temperature difference Is smaller than conventional primers. Therefore, the polysiloxane hard resin film coated on the surface of the primer film is less likely to crack or peel over a long period of time.
However, it was found that the reproducibility of the primer composition, such as cracking and peeling, decreased in the long-term weather resistance test depending on the environmental temperature or humidity during application and curing, and further improvement was necessary. .

For the purpose of solving the above problems, the present inventor has developed an ultraviolet absorbing vinyl monomer, an alkoxysilyl group-containing vinyl monomer, and a copolymer of vinyl monomers copolymerizable with these monomers. And a method for producing a hydrolysis primer composition in which silica fine particles are hydrolyzed in advance and the remaining water is captured by a dehydrating agent such as an orthocarboxylic acid ester [Japanese Patent Laid-Open No. 2010-65076 (Patent Document 8). ]]. The film coated and cured with the primer composition is preliminarily hydrolyzed with a hydrolyzable silyl group to form a SiOH group so that the crosslinking reaction proceeds easily. The performance reproducibility as a primer was improved.
However, the primer composition is strongly colored by adding an orthocarboxylic acid ester such as ethyl orthoformate, and has a disadvantage that the coating film is colored when the primer coating film is thickened.

JP 56-92059 A JP-A-1-149878 Japanese Patent Laid-Open No. 2001-114841 Japanese Patent No. 3106696 JP 2001-214122 A JP 2001-47574 A JP 2008-120986 A JP 2010-65076 A

  The present invention has been made in view of the above circumstances, and forms a protective film excellent in weather resistance without defects such as cracks, peeling, and yellowing over a long period of time, and has reproducibility of these performances and is free of coloring. And a method for producing a weather-resistant coating composition which has good storage stability and does not thicken or gel even after long-term storage or use, a method for preventing coloration of the composition, and a coated article using the composition The purpose is to provide.

As a result of intensive studies to achieve the above object, the present inventor has dispersed a vinyl polymer (A) in which a hydrolyzable silyl group and an organic ultraviolet absorbing group are bonded to side chains, respectively, in an organic solvent. The following steps [1] or [2] using the fine silica particles (B), the organic solvent (C) containing a carbonyl group, the orthocarboxylic acid ester (D), and a tertiary amine or an organic acid salt thereof (E) It was found that the above problems can be solved by a coating composition obtained by a production method comprising
[1]
(I) preparing a coating precursor comprising one or more components excluding the component (E),
(II) A step of adding the component (E) to the coating precursor obtained in the step (I).
However, when there is an unadded component in the step, it is added after the step (II).
[2]
(III) preparing a coating precursor containing the component (A) alone or one or more components excluding the component (D) and the component (A);
(IV) A step of performing partial hydrolysis by adding water to the coating precursor obtained in the step (III),
(V) A step of adding the component (D) to the coating precursor partial hydrolyzate obtained in the step (IV).
However, when there is an unadded component in the step, it is added after step (V).

That is, the present inventor can obtain a coating film that imparts long-term weather resistance to a thermoplastic resin molded article such as polycarbonate, has no coloration, has good storage stability, and has increased viscosity even when stored or used for a long time. Various coating compositions that do not gelate were studied.
As a result, a vinyl polymer (A) in which a hydrolyzable silyl group and an organic UV-absorbing group are bonded to side chains, silica fine particles (B) dispersed in an organic solvent, and a carbonyl group are included as constituents of the composition. The coating composition containing the organic solvent (C) and the orthocarboxylic acid ester (D) contains a siloxane crosslink between hydrolyzable silyl groups and / or SiOH groups of the vinyl polymer (A), and the vinyl A dense three-dimensional crosslinked network formed by siloxane crosslinking between the hydrolyzable silyl group and / or SiOH group of the polymer (A) and the SiOH group on the surface of the silica fine particles (B), and the silica fine particles (B ) Due to its low expansion property, the linear expansion coefficient is lowered, and the expansion / contraction due to the temperature difference is smaller than that of the conventional coating film. Therefore, the silicon oxide-containing hard coating coated on the surface of the coating coating does not crack or peel for a long time.
In the vinyl polymer (A), the organic UV-absorbing group is bonded to the side chain and is crosslinked in the film made of the coating composition. Fixing makes it extremely difficult for UV-absorbing groups to migrate to the coating surface, eliminating the appearance of whitening and poor adhesion, and absorbing UV rays over time with no elution or outflow to water or solvents. The weather resistance is significantly improved and the function is maintained over a long period of time because the ultraviolet light absorbing group does not evaporate from the coating even when heat curing is performed at a high temperature.
Further, when the coating composition is stored, there is an advantage that moisture in the composition is removed due to the effect of the orthocarboxylic acid ester (D), and the storage stability is remarkably improved, whereas the composition is strongly colored. However, by adding a tertiary amine or an organic acid salt (E) thereof to the composition, the problem of coloring was solved.

Accordingly, the present invention provides the following method for producing a weather-resistant coating composition, a method for preventing the coloration of the composition, and a coated article comprising the composition.
[1]
A method for producing a weather-resistant coating composition comprising the following components (A) to (E) and comprising the following steps (I) and (II):
A vinyl polymer (A) in which a hydrolyzable silyl group and an organic ultraviolet absorbing group are bonded to side chains,
Silica fine particles (B) dispersed in an organic solvent,
An organic solvent (C) containing a carbonyl group,
Orthocarboxylic acid ester (D),
A tertiary amine or an organic acid salt thereof (E),
(I) preparing a coating precursor comprising one or more components excluding the component (E),
(II) A step of adding the component (E) to the coating precursor obtained in the step (I).
However, when there is an unadded component in the step, it is added after the step (II).
[2]
A method for producing a weather-resistant coating composition comprising the following components (A) to (E) and comprising the following steps (III) to (V):
A vinyl polymer (A) in which a hydrolyzable silyl group and an organic ultraviolet absorbing group are bonded to side chains,
Silica fine particles (B) dispersed in an organic solvent,
An organic solvent (C) containing a carbonyl group,
Orthocarboxylic acid ester (D),
A tertiary amine or an organic acid salt thereof (E),
(III) preparing a coating precursor containing the component (A) alone or one or more components excluding the component (D) and the component (A);
(IV) A step of performing partial hydrolysis by adding water to the coating precursor obtained in the step (III),
(V) A step of adding the component (D) to the coating precursor partial hydrolyzate obtained in the step (IV).
However, when there is an unadded component in the step, it is added after step (V).
[3]
[2] The amount of water used for hydrolysis is less than 5 moles with respect to 1 mole of hydrolyzable groups of the hydrolyzable silyl group in the vinyl polymer (A). Manufacturing method.
[4]
The production method according to [1], [2] or [3], wherein the orthocarboxylic acid ester (D) is at least one selected from methyl orthoformate, ethyl orthoformate, methyl orthoacetate and ethyl orthoacetate.
[5]
The production method according to any one of [1] to [4], wherein the organic solvent (C) containing a carbonyl group is at least one selected from ketones having 3 to 10 carbon atoms and carboxylic acid esters.
[6]
A tertiary amine or an organic acid salt thereof (E) is tributylamine, pyridine, 1,8-diazabicyclo [5.4.0] undecene-7, 1,5-diazabicyclo [4.3.0] nonene-5 and The production method according to any one of [1] to [5], which is at least one selected from those carboxylates.
[7]
A vinyl polymer (A) in which a hydrolyzable silyl group and an organic UV-absorbing group are bonded to the side chain is a vinyl monomer (a) in which a hydrolyzable silyl group is bonded through a C-Si bond. -1), a vinyl monomer (a-2) having an organic ultraviolet absorbing group, an epoxy group-containing vinyl monomer (a-3-i), and other copolymerizable monomers The production method according to any one of [1] to [6], which is a vinyl polymer obtained by copolymerizing a monomer component comprising (a-3-ii).
[8]
A vinyl polymer (A) in which a hydrolyzable silyl group and an organic ultraviolet absorbing group are bonded to side chains, silica fine particles (B) dispersed in an organic solvent, an organic solvent (C) containing a carbonyl group, and A method for preventing coloration of a weather-resistant coating composition containing an orthocarboxylic acid ester (D), wherein a tertiary amine or an organic acid salt (E) thereof is added to the composition. A method for preventing coloration of a weather-resistant coating composition.
[9]
The method for preventing coloring according to [8], wherein the orthocarboxylic acid ester (D) is at least one selected from methyl orthoformate, ethyl orthoformate, methyl orthoacetate and ethyl orthoacetate.
[10]
[8] or [9], wherein the organic solvent (C) containing a carbonyl group is at least one selected from ketones having 3 to 10 carbon atoms and carboxylic acid esters.
[11]
A tertiary amine or an organic acid salt thereof (E) is tributylamine, pyridine, 1,8-diazabicyclo [5.4.0] undecene-7, 1,5-diazabicyclo [4.3.0] nonene-5 and The coloring prevention method according to any one of [8] to [10], which is at least one selected from those carboxylates.
[12]
A vinyl polymer (A) in which a hydrolyzable silyl group and an organic UV-absorbing group are bonded to the side chain is a vinyl monomer (a) in which a hydrolyzable silyl group is bonded through a C-Si bond. -1), a vinyl monomer (a-2) having an organic ultraviolet absorbing group, an epoxy group-containing vinyl monomer (a-3-i), and other copolymerizable monomers The method for preventing coloring according to any one of [8] to [11], wherein the method is a vinyl polymer obtained by copolymerizing a monomer component comprising (a-3-ii).
[13]
It is formed by laminating a silicon oxide-containing hard coating on the surface of a coating formed by applying and curing the coating composition produced by the method according to any one of [1] to [7] on a substrate. Characteristic coated article.
[14]
The silicon oxide-containing hard coating has the following general formula (1)
(R ⁷ ) _m Si (OR ⁸ ) _4-m (1)
(In the formula, R ⁷ represents a monovalent organic group having 1 to 10 carbon atoms, R ⁸ represents a hydrogen atom or a monovalent organic group, and m is 0, 1 or 2.)
The coated article according to [13], which is formed from a hard coating composition containing one or more hydrolysates or co-hydrolysates of organooxysilane represented by the formula (1) and silica fine particles.

Since the coating composition of the present invention can retain a large amount of organic UV-absorbing groups in the film, the weather resistance is greatly improved, and the organic UV-absorbing groups are immobilized in the film by crosslinking with siloxane. Therefore, the ultraviolet ray-absorbing group is prevented from flowing out with time. Also, the hydrolytic silyl groups in the vinyl polymer, or the siloxane crosslinking between the vinyl polymer and the silica fine particles proceeds, so that the resulting coating film has a low coefficient of linear expansion and a binder with high weather resistance. Thus, an ultraviolet-absorbing protective coating excellent in water resistance, solvent resistance and weather resistance is provided. If this coating composition is applied and cured on an article having inferior weather resistance, coloring and deterioration of the article can be suppressed and good weather resistance can be imparted. In addition, when a vinyl polymer containing a hydrolyzable silyl group is hydrolyzed in advance, the coating composition becomes markedly thickened and gelled over time. However, by adding an orthocarboxylic acid ester, Long-term storage stability can be ensured without gelation. Further, strong coloring of the composition caused by the addition of orthocarboxylic acid ester can be prevented by adding a tertiary amine or an organic acid salt thereof.
The plastic article coated with the coating composition of the present invention, particularly the polycarbonate resin, can impart excellent transparency and weather resistance, and further, by laminating a hard coating containing silicon oxide on the coating. In addition, since scratch resistance and chemical resistance can be imparted together, it is suitable for outdoor use such as a window of a transport device such as a vehicle or an airplane, a windshield, a window of a building, or a sound insulation wall of a road.

In the coating composition of Example 1, it is a photograph before and after addition of tributylamine.

The weather resistant coating composition of the present invention comprises the following components (A) to (E).
(A) a vinyl polymer in which a hydrolyzable silyl group and an organic ultraviolet absorbing group are each bonded to a side chain;
(B) silica fine particles dispersed in an organic solvent,
(C) an organic solvent containing a carbonyl group,
(D) orthocarboxylic acid ester,
(E) A tertiary amine or an organic acid salt thereof.

The method for producing a weather resistant coating composition of the present invention includes the following step [1] or [2].
[1]
(I) preparing a coating precursor comprising one or more components excluding the component (E),
(II) A step of adding the component (E) to the coating precursor obtained in the step (I).
However, when there is an unadded component in the step, it is added after the step (II).
[2]
(III) preparing a coating precursor containing the component (A) alone or the component (A) and one or more components excluding the component (D);
(IV) A step of performing partial hydrolysis by adding water to the coating precursor obtained in the step (III),
(V) A step of adding the component (D) to the coating precursor partial hydrolyzate obtained in the step (IV).
However, when there is an unadded component in the step, it is added after step (V).

  Further, the method for preventing coloration of the weather-resistant coating composition of the present invention includes a vinyl polymer (A) in which the hydrolyzable silyl group and the organic ultraviolet absorbing group are bonded to side chains, and silica dispersed in an organic solvent. By adding a tertiary amine or an organic acid salt thereof (E) to a coating composition containing fine particles (B), an organic solvent (C) containing a carbonyl group, and an orthocarboxylic acid ester (D) Coloring can be prevented.

  As described above, the essential components in producing the weather resistant coating composition according to the present invention are the vinyl polymer (A) in which the hydrolyzable silyl group and the organic ultraviolet absorbing group are bonded to the side chain, Silica fine particles (B) dispersed in an organic solvent, an organic solvent (C) containing a carbonyl group, an orthocarboxylic acid ester (D), and a tertiary amine or an organic acid salt thereof (E).

  As the vinyl polymer in which the hydrolyzable silyl group and the organic ultraviolet absorbing group of the component (A) are each bonded to the side chain, the hydrolyzable silyl group is bonded to the vinyl polymer main chain via a C-Si bond. It is preferable that it is bonded, and it is also preferable that the organic ultraviolet absorbing group is bonded to the vinyl polymer main chain. Such a polymer includes a vinyl monomer (a-1) in which a hydrolyzable silyl group is bonded via a C-Si bond, and a vinyl monomer (a-) having an organic ultraviolet absorbing group. It can be obtained by copolymerizing a monomer component consisting of 2) and another monomer (a-3) copolymerizable with these monomers.

  Here, the vinyl monomer in which the hydrolyzable silyl group of (a-1) is bonded through a C—Si bond is composed of one vinyl polymerizable functional group and one or more hydrolyzed monomers in one molecule. Any substance containing a decomposable silyl group can be used.

  As a vinyl polymerizable functional group, a C2-C12 organic group including a vinyl group, a vinyloxy group, a (meth) acryloxy group, and an (α-methyl) styryl group can be shown. Specifically, vinyl group, 5-hexenyl group, 9-decenyl group, vinyloxymethyl group, 3-vinyloxypropyl group, (meth) acryloxymethyl group, 3- (meth) acryloxypropyl group, 11- Specific examples include (meth) acryloxyundecyl group, vinylphenyl group, isopropenylphenyl group, and vinylphenylmethyl group. From the viewpoint of reactivity and availability, it is preferable to use an organic group containing a (meth) acryloxy group, and it is particularly preferable to use a (meth) acryloxypropyl group.

  Hydrolyzable groups include alkoxy groups such as methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, isobutoxy group, sec-butoxy group, and tert-butoxy group, and acyloxy groups such as phenoxy group and acetyloxy group. Specific examples include oxime groups such as butanoxime groups, amino groups such as amino groups and methylamino groups, and halogen groups such as chloro groups. Alkoxy groups such as a methoxy group and an ethoxy group can be suitably used because of easy controllability of hydrolyzability and availability.

  Examples of substituents other than the above substituents include alkyl groups such as methyl, ethyl, propyl, hexyl, and decyl groups, and phenyl groups. From the viewpoint of availability, a methyl group is preferably used.

  Examples of the vinyl monomer (a-1) in which a hydrolyzable silyl group is bonded via a C—Si bond include methacryloxymethyltrimethoxysilane, methacryloxypropyltrimethoxysilane, methacryloxyundecyltrimethoxy. Silane, methacryloxypropylmethyldimethoxysilane, methacryloxypropyldimethylmethoxysilane, methacryloxypropyltriethoxysilane, acryloxypropyltrimethoxysilane, acryloxypropylmethyldimethoxysilane, acryloxypropyldimethylmethoxysilane, acryloxypropyltriethoxysilane , Acryloxymethyltrimethoxysilane, acryloxyundecyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinylmethyldimethyl Kishishiran, allyl trimethoxysilane, styryl trimethoxysilane, styryl methyldimethoxysilane, and the like styryl triethoxysilane. Among these, methacryloxypropyltrimethoxysilane, methacryloxypropylmethyldimethoxysilane, methacryloxypropyldimethylmethoxysilane, acryloxypropyltrimethoxysilane, acryloxy, etc. Roxypropylmethyldimethoxysilane is preferred.

  The amount of the vinyl monomer in which the hydrolyzable silyl group of (a-1) is bonded via a C—Si bond is preferably 1 to 50% by mass, particularly preferably 3 to 40% by mass in the copolymer composition. . If it is less than 1% by mass, the formation of a siloxane network by crosslinking between silica fine particles and the above vinyl copolymers is insufficient, and the linear expansion coefficient of the coating film is not sufficiently lowered, and the heat resistance and durability may not be improved. . On the other hand, if it exceeds 50% by mass, the crosslink density becomes too high and it becomes hard and the adhesiveness is lowered, or the unreacted hydrolyzable group or SiOH group tends to remain, and post-crosslinking occurs with time and cracks occur. It may be easy to do.

  Next, the vinyl monomer (a-2) having an organic ultraviolet absorbing group will be described. Any compound can be used as long as it contains an ultraviolet absorbing group and a vinyl polymerizable group in the molecule.

  As a specific example of the vinyl monomer having such an organic ultraviolet absorbing group, a (meth) acrylic monomer having an ultraviolet absorbing group in the molecule is shown, and the following general formula (2) The benzotriazole type compound represented, and the benzophenone type compound represented by following General formula (3) can be mentioned.

(In the formula, X represents a hydrogen atom or a chlorine atom. R ¹ represents a hydrogen atom, a methyl group, or a tertiary alkyl group having 4 to 8 carbon atoms. R ² represents a linear or branched carbon. And represents an alkylene group having a number of 2 to 10. R ³ represents a hydrogen atom or a methyl group, and n represents 0 or 1.)

(Wherein R ³ represents the same meaning as described above. R ⁴ represents an unsubstituted or substituted linear or branched alkylene group having 2 to 10 carbon atoms. R ⁵ represents a hydrogen atom or a hydroxyl group. R ⁶ represents a hydrogen atom, a hydroxyl group, or an alkoxy group having 1 to 6 carbon atoms.)

In the general formula (2), examples of the tertiary alkyl group having 4 to 8 carbon atoms represented by R ¹ include a tert-butyl group, a tert-pentyl group, a tert-hexyl group, a tert-heptyl group, and a tert-octyl group. Group, di-tert-octyl group and the like.
Examples of the linear or branched alkylene group having 2 to 10 carbon atoms represented by R ² include an ethylene group, a trimethylene group, a propylene group, a tetramethylene group, a 1,1-dimethyltetramethylene group, and a butylene group. Octylene group, decylene group and the like.

In the general formula (3), the linear or branched alkylene group having 2 to 10 carbon atoms represented by R ⁴ is the same as those exemplified for R ² above, or hydrogen thereof. A group in which a part of the atoms is substituted with a halogen atom such as fluorine, bromine or chlorine, a hydroxyl group, or the like can be given. Examples of the alkoxy group represented by R ⁶ include a methoxy group, an ethoxy group, a propoxy group, and a butoxy group.

  Specific examples of the benzotriazole-based compound represented by the general formula (2) include 2- (2′-hydroxy-5 ′-(meth) acryloxyphenyl) -2H-benzotriazole, 2- (2 '-Hydroxy-3'-tert-butyl-5'-(meth) acryloxymethylphenyl) -2H-benzotriazole, 2- [2'-hydroxy-5 '-(2- (meth) acryloxyethyl) phenyl ] -2H-benzotriazole, 2- [2′-hydroxy-3′-tert-butyl-5 ′-(2- (meth) acryloxyethyl) phenyl] -5-chloro-2H-benzotriazole, 2- [ And 2'-hydroxy-3'-methyl-5 '-(8- (meth) acryloxyoctyl) phenyl] -2H-benzotriazole.

  Specific examples of the benzophenone compound represented by the general formula (3) include 2-hydroxy-4- (2- (meth) acryloxyethoxy) benzophenone and 2-hydroxy-4- (4- (meta ) Acryloxybutoxy) benzophenone, 2,2′-dihydroxy-4- (2- (meth) acryloxyethoxy) benzophenone, 2 ′, 4-dihydroxy-4 ′-(2- (meth) acryloxyethoxy) benzophenone, 2,2 ′, 4-trihydroxy-4 ′-(2- (meth) acryloxyethoxy) benzophenone, 2-hydroxy-4- (3- (meth) acryloxypropoxy) benzophenone, 2-hydroxy-4- ( And 3- (meth) acryloxypropoxy) benzophenone.

As the UV-absorbing vinyl monomer, a benzotriazole compound represented by the formula (2) is preferable, and 2- [2′-hydroxy-5 ′-(2- (meth) acryloxyethyl) phenyl is particularly preferable. ] -2H-benzotriazole is preferably used.
Furthermore, you may use the said ultraviolet absorptive vinyl-type monomer individually by 1 type or in mixture of 2 or more types.

  The usage-amount of the vinylic monomer (a-2) which has an organic type ultraviolet absorptive group is 1-30 mass% by copolymerization composition, 3-25 mass% is especially preferable. If it is less than 1% by mass, good weather resistance may not be obtained, and if it exceeds 30% by mass, the adhesion of the coating film may be lowered, or coating film appearance defects such as whitening may be caused.

  Next, the other monomer (a-3) copolymerizable with the monomers (a-1) and (a-2) is not particularly limited as long as it is a copolymerizable monomer. And epoxy group-containing vinyl monomers (a-3-i) and other monomers (a-3-ii).

  Specific examples of the epoxy group-containing vinyl monomer (a-3-i) include glycidyl (meth) acrylate.

  Other monomers (a-3-ii) include (meth) acrylic monomers, (meth) acrylic monomers having a cyclic hindered amine structure, (meth) acrylic acid esters, (meth) acrylonitrile, Examples thereof include (meth) acrylamide, alkyl vinyl ether, alkyl vinyl ester, styrene, and derivatives thereof.

  Here, specific examples of the (meth) acrylic monomer having a cyclic hindered amine structure include 2,2,6,6-tetramethyl-4-piperidinyl methacrylate, 1,2,2,6,6- Examples include pentamethyl-4-piperidinyl methacrylate, and two or more of these light stabilizers may be used in combination.

Specific examples of (meth) acrylic acid esters and derivatives thereof include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, (meth) acrylic acid. n-butyl, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, t-butyl (meth) acrylate, n-pentyl (meth) acrylate, isopentyl (meth) acrylate, (meth) acrylic acid n-hexyl, isohexyl (meth) acrylate, n-heptyl (meth) acrylate, isoheptyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, (meth) acrylic acid Isooctyl, n-nonyl (meth) acrylate, isononyl (meth) acrylate, (meth) acrylic N-decyl acid, isodecyl (meth) acrylate, n-undecyl (meth) acrylate, n-dodecyl (meth) acrylate, lauryl (meth) acrylate, palmityl (meth) acrylate, stearyl (meth) acrylate Cyclohexyl (meth) acrylate, 4-methylcyclohexyl (meth) acrylate, 4-t-butylcyclohexyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, (meth) (Meth) acrylic acid esters of monohydric alcohols such as dicyclopentenyloxyethyl acrylate and benzyl (meth) acrylate;
2-methoxyethyl (meth) acrylate, 2-methoxypropyl (meth) acrylate, 3-methoxypropyl (meth) acrylate, 2-methoxybutyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, 4-methoxybutyl ( Of alkoxy (poly) alkylene glycols such as meth) acrylate, methoxypolyethylene glycol (meth) acrylate (the number of ethylene glycol units is, for example, 2 to 20), and methoxypolypropylene glycol (meth) acrylate (the number of propylene glycol units is, for example, 2 to 20). (Meth) acrylic acid esters;
2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl ( (Meth) acrylate, glycerin mono (meth) acrylate, pentaerythritol mono (meth) acrylate, polyethylene glycol mono (meth) acrylate (the number of ethylene glycol units is, for example, 2 to 20), polypropylene glycol mono (meth) acrylate (the number of propylene glycol units) Are mono (meth) acrylic acid esters of polyhydric alcohols such as 2-20);
Ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, glycerin di (meth) acrylate, glycerin tri (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol tetra ( (Meth) acrylate, 1,4-cyclohexanediol di (meth) acrylate, polyethylene glycol di (meth) acrylate (the number of ethylene glycol units is, for example, 2 to 20), polypropylene glycol di (meth) acrylate (the number of propylene glycol units is, for example, 2 To 20) poly (meth) acrylic acid esters of polyhydric alcohols;
Succinic acid mono [2- (meth) acryloyloxyethyl], succinic acid di [2- (meth) acryloyloxyethyl], adipic acid mono [2- (meth) acryloyloxyethyl], adipic acid di [2- (meta ) Acryloyloxyethyl], mono [2- (meth) acryloyloxyethyl] phthalate, di [2- (meth) acryloyloxyethyl] phthalate, and other nonpolymerizable polybasic acids and hydroxyalkyl (meth) acrylates (Poly) esters of
(Meth) acrylic acid 2-aminoethyl, (meth) acrylic acid 2- (N-methylamino) ethyl, (meth) acrylic acid 2- (N, N-dimethylamino) ethyl, (meth) acrylic acid 2- ( N-ethylamino) ethyl, (meth) acrylic acid 2- (N, N-diethylamino) ethyl, (meth) acrylic acid 3- (N, N-dimethylamino) propyl, (meth) acrylic acid 4- (N, Examples thereof include amino group-containing (meth) acrylic acid esters such as (N-dimethylamino) butyl.

Specific examples of the derivative of (meth) acrylonitrile include α-chloroacrylonitrile, α-chloromethylacrylonitrile, α-trifluoromethylacrylonitrile, α-methoxyacrylonitrile, α-ethoxyacrylonitrile, vinylidene cyanide, and the like. it can.
Specific examples of (meth) acrylamide derivatives include N-methyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N-ethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N- Methoxy (meth) acrylamide, N, N-dimethoxy (meth) acrylamide, N-ethoxy (meth) acrylamide, N, N-diethoxy (meth) acrylamide, diacetone (meth) acrylamide, N-methylol (meth) acrylamide, N- (2-hydroxyethyl) (meth) acrylamide, N, N-dimethylaminomethyl (meth) acrylamide, N- (2-dimethylamino) ethyl (meth) acrylamide, N, N′-methylenebis (meth) acrylamide, N, N'-ethylenebis (meth) acrylic Mention may be made of the bromide and the like.

Specific examples of the alkyl vinyl ether include methyl vinyl ether, ethyl vinyl ether, butyl vinyl ether, hexyl vinyl ether and the like.
Specific examples of the alkyl vinyl ester include vinyl formate, vinyl acetate, vinyl acrylate, vinyl butyrate, vinyl caproate, and vinyl stearate.
Specific examples of styrene and its derivatives include styrene, α-methylstyrene, vinyltoluene and the like.

Among these monomers, (a-3-i) is preferably glycidyl (meth) acrylate, and (a-3-ii) is preferably a (meth) acrylate ester, particularly (meth). Methyl acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, n-hexyl (meth) acrylate, 2- (meth) acrylic acid 2- Ethylhexyl, isononyl (meth) acrylate, lauryl (meth) acrylate, cyclohexyl (meth) acrylate, 4-methylcyclohexyl (meth) acrylate, 4-t-butylcyclohexyl (meth) acrylate, (meth) acrylic acid Isobornyl, dicyclopentanyl (meth) acrylate, dicyclopentenyloxye (meth) acrylate Le, and the like are preferable.
As the other copolymerizable monomer (a-3), the monomers can be used alone or in admixture of two or more. Furthermore, it is more preferable to use a mixture of (a-3-i) and (a-3-ii).

The amount of the other copolymerizable monomer (a-3) used is the sum of the amounts used of (a-3-i) and (a-3-ii), and is 20 to 98% by mass in the copolymer composition. In particular, the range of 35 to 94% by mass is preferable. When the amount of the monomer (a-3) is too large, crosslinking between the obtained vinyl copolymers and silica fine particles becomes insufficient, the coefficient of linear expansion of the coating film is not lowered, and heat resistance and durability are not improved. In some cases, good weather resistance may not be obtained. If the amount is too small, the cross-linking density may be too high, resulting in a decrease in adhesiveness or a coating appearance failure such as whitening.
Among them, the amount of (a-3-i) used is preferably in the range of 0 to 20% by mass, particularly 1 to 10% by mass in the copolymer composition. When there is too much (a-3-i), the thickening by the crosslinking | crosslinking of the epoxy group with time will become remarkable, and the storage stability at the time of setting it as a composition may fall.

  In the vinyl polymer (A), a vinyl monomer (a-1) in which a hydrolyzable silyl group is bonded via a C-Si bond, and a vinyl monomer containing an organic ultraviolet absorbing group The copolymerization reaction of the body (a-2) and the other copolymerizable monomer (a-3) can be carried out by a known method, for example, in a mixture containing these monomers. , A radical polymerization initiator selected from peroxides such as dicumyl peroxide and benzoyl peroxide, or azo compounds such as azobisisobutyronitrile and azobisisovaleronitrile, and heated (preferably 50 ˜150 ° C., particularly 70 to 120 ° C., for 1 to 10 hours, particularly 3 to 8 hours). In this case, the reaction can be performed in the presence of an organic solvent. Examples of the organic solvent include diacetone alcohol, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, Isobutyl alcohol, isopropyl alcohol, n-butyl alcohol, n-propyl alcohol, acetone, methyl ethyl ketone, methyl isobutyl ketone, acetyl acetone, ethyl acetate, butyl acetate, xylene, toluene and the like can be used.

  In addition, it is preferable that the polystyrene conversion weight average molecular weights by gel permeation chromatography (GPC) of this vinyl polymer are 1,000-300,000, especially 5,000-250,000. If the molecular weight is too large, the viscosity becomes too high and it may be difficult to synthesize or difficult to handle.If it is too small, it may cause poor appearance such as whitening of the coating film, and sufficient adhesion, durability, and weather resistance will be obtained. It may not be possible.

  The vinyl polymer is preferably used as an organic solvent solution. Examples of the organic solvent are the same as the organic solvents used in the above reaction. The solid content concentration of the solution is preferably 10 to 90% by mass, and particularly preferably 20 to 80% by mass. If the solid content concentration is too high, the viscosity may be increased and the handleability may be lowered, and if it is too low, the amount used may be excessive when used as a coating composition.

The silica fine particles (B) dispersed in an organic solvent, which is another essential component in the coating composition of the present invention, will be described.
The silica fine particles (B) are not particularly limited as long as they are dispersed in an organic solvent. Here, since the silica fine particles (B) have SiOH groups on the particle surfaces, the hydrolyzable silyl groups and / or the hydrolyzable silyl groups of the vinyl polymer of the component (A) at the time of forming a cured film of the composition. The siloxane crosslinks with the hydrolyzed SiOH groups so that the hydrolyzable silyl groups and / or SiOH groups of the vinyl polymer (A) and the SiOH groups on the surface of the silica fine particles (B) An organic-inorganic composite is produced by siloxane crosslinking. As a result, the linear expansion coefficient decreases.

  Examples of the organic solvent of the silica fine particles (B) dispersed in such an organic solvent include methanol, ethanol, isopropanol, n-butanol, ethylene glycol, ethyl cellosolve, butyl cellosolve, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, dimethylformamide. , Dimethylacetamide, methyl ethyl ketone, methyl isobutyl ketone, and a mixture of xylene / n-butanol. Of these, ethylene glycol, ethyl cellosolve, butyl cellosolve, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, methyl ethyl ketone, methyl isobutyl ketone and the like are preferable in consideration of the solubility of the vinyl polymer of component (A).

  Moreover, when the dispersibility and transparency in a coating cured film are considered, it is preferable that the primary particle diameter of a silica fine particle (B) is 0.5-100 nm. More preferably, 2-50 nm is good. If it exceeds 100 nm, the dispersion stability of the silica fine particles (B) in the present composition may be lowered, or the transparency of the cured film may be significantly lowered.

  The solid content concentration of the silica fine particles (B) dispersed in the organic solvent is preferably 10 to 50% by mass, and particularly preferably 20 to 40% by mass. If the solid content concentration is too high, the silica fine particles (B) may be easily aggregated, and if the solid content concentration is too low, the amount of the coating composition used may be excessive.

The silica fine particles (B) dispersed in such an organic solvent are preferably colloidal silica dispersed in an organic solvent called an organosilica sol. Especially ethylene glycol dispersed silica sol, ethylene glycol mono n-propyl ether dispersed silica sol, ethyl cellosolve dispersed silica sol, butyl cellosolve dispersed silica sol, propylene glycol monomethyl ether dispersed silica sol, propylene glycol monomethyl ether acetate dispersed silica sol, methyl ethyl ketone dispersed silica sol, methyl isobutyl ketone dispersed silica sol It can be illustrated.
Furthermore, the silica fine particles (B) dispersed in the organic solvent can be used alone or in admixture of two or more.

  In addition, a commercial item is used as colloidal silica disperse | distributed to these organic solvents. For example, in addition to PMA-ST, PGM-ST, MEK-ST, MIBK-ST (all manufactured by Nissan Chemical Industries, Ltd.) used in the examples described later, IPA-ST-L, IPA-ST-MS, EG-ST-ZL, DMAC-ST-ZL, XBA-ST (all manufactured by Nissan Chemical Industries, Ltd.), OSCAL1132, 1332, 1532, 1722, ELCOM ST-1003SIV (all catalytic conversion) Kogyo Co., Ltd.).

  The compounding amount of the silica fine particles (B) dispersed in the organic solvent should contain 0.1 to 100 parts by mass of the solid content of the silica fine particles (B) with respect to 100 parts by mass of the resin content of the vinyl polymer (A). It is preferable to contain 1-50 mass parts more preferably. When the solid content of the silica fine particles (B) is added in excess of 100 parts by mass, the crosslinking density in the cured coating layer of the coating composition of the present invention becomes too high, and the hardness of the resulting film increases, There is a possibility that adhesion to the silicon oxide-containing hard coating laminated on the surface of the coating layer may be poor, or that it may be easily thickened and gelled. On the other hand, if the amount is less than 0.1 parts by mass, the resulting coating has a sufficiently low crosslinking density, and the expected adhesion and crack resistance may not be obtained.

  The organic solvent (C) containing a carbonyl group, which is an essential component in the coating composition of the present invention, will be described. By adding an organic solvent (C) containing a carbonyl group, the compatibility with the vinyl polymer (A) and the silica fine particles (B) can be improved. Adhesiveness can be improved.

  As such an organic solvent (C), any organic solvent containing a carbonyl group can be used. Preferably, a C3-C10 ketone and carboxylic acid ester are mentioned. Specific examples of the organic solvent (C) include diacetone alcohol, propylene glycol monomethyl ether acetate, ethylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethylene glycol monoethyl ether acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, Examples thereof include cyclopentanone, cyclohexanone, acetylacetone, methyl formate, ethyl formate, butyl formate, methyl acetate, ethyl acetate, and butyl acetate. Among them, from the viewpoint of easy dissolution of the vinyl polymer (A) and volatility at the time of coating, diacetone alcohol, propylene glycol monomethyl ether acetate, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, ethyl formate Ethyl acetate is preferred.

  The blending amount of the organic solvent (C) containing a carbonyl group is preferably 0.5 to 95 parts by mass, and more preferably 1 to 50 parts by mass with respect to a total of 100 parts by mass of the volatile components in the coating composition. When the organic solvent (C) containing a carbonyl group is added in an amount exceeding 95 parts by mass, the coating composition of the present invention is applied to a plastic resin substrate such as polycarbonate, so-called etching that erodes the resin substrate surface. The effect becomes too large, and the coating film appearance may be abnormal in appearance such as streaks, whitening and cracks. Conversely, if the blending amount is less than 0.5 parts by mass, the etching effect on the resin base material cannot be expected, and the adhesion to the base material may be reduced.

The orthocarboxylic acid ester (D), which is an essential component in the coating composition of the present invention, will be described. The orthocarboxylic acid ester (D) acts as a so-called dehydrating agent that removes moisture in the coating composition of the present invention. Here, the moisture is moisture contained in the components or moisture that absorbs moisture when the coating composition is stored. As a result, the hydrolyzable silyl group in the vinyl polymer (A) is gradually reduced. It hydrolyzes and condenses to prevent the coating composition from thickening and gelling over time.
Moreover, when the above-mentioned hydrolyzable silyl group-containing vinyl polymer (A) is hydrolyzed in advance, the coating composition becomes markedly thickened and gelled over time, but the orthocarboxylic acid ester (D) is added. By doing so, long-term storage stability can be ensured without thickening or gelling.

  Specific examples of the orthocarboxylic acid ester (D) include methyl orthoformate, ethyl orthoformate, propyl orthoformate, butyl orthoformate, methyl orthoacetate, ethyl orthoacetate, propyl orthoacetate and the like.

  The amount of orthocarboxylic acid ester (D) added may be such that water remaining in the coating composition is removed, preferably 1 to 20 moles per mole of water, and 2 to 10 moles. Particularly preferred. When the orthocarboxylic acid ester (D) is added in excess of 20 moles relative to 1 mole of water, abnormal coating appearance such as streaks, whitening, and cracks tends to occur when the coating composition is formed into a film. If the amount is less than 1 mol, the remaining moisture in the coating composition cannot be sufficiently dehydrated, and the expected storage stability such as thickening and gelation over time may not be obtained.

  The tertiary amine or its organic acid salt (E), which is an essential component in the coating composition of the present invention, will be described. The component (E) serves to prevent coloring of the coating composition comprising the components (A) to (D). The coloring of the composition here is a phenomenon observed when the four components (A) to (D) coexist, and is colorless or light yellow immediately after mixing, but gradually changes to purple or brown. To do. The cause of this coloring is unknown, but the UV-absorbing group in component (A), the carbonyl group in component (C) and the orthocarboxylic acid ester in component (D) are probably SiOH groups in silica fine particles (B). It is presumed that they interacted under acidic conditions. In fact, this coloring is slight or does not occur if none of the components (A) to (D) is present.

As the component (E), any tertiary amine or organic acid salt thereof can be used.
Examples of component (E) include symmetrical tertiary amines such as triethylamine, tripropylamine, tributylamine;
Asymmetric tertiary amines such as isobutyldimethylamine, t-butyldimethylamine, octyldimethylamine, benzyldimethylamine, 2- (dimethylaminomethyl) phenol, N, N-dimethylcyclohexylamine, N-methyldicyclohexylamine;
Pyridine, N-methylpiperidine, 1,2,2,6,6-pentamethylpiperidine, N, N-dimethylpiperazine, triethylenediamine, 1,8-diazabicyclo [5.4.0] undecene-7 (DBU), Cyclic tertiary amines such as 1,5-diazabicyclo [4.3.0] nonene-5 (DBN);
Examples include tertiary amine organic acid salts such as tertiary amine formate, acetate, octylate, oleate, p-toluenesulfonate, orthophthalate, and the like. Among the acid salts, formate and acetate of triethylamine and tributylamine, 1,8-diazabicyclo [5.4.0] undecene-7, 1,5-diazabicyclo [4.3.0] nonene-5 formate Organic acids of tertiary amines such as acetate and octylate are preferred.
As the tertiary amine or organic acid salt thereof as component (E), tributylamine, pyridine, DBU, DBN, and carboxylates thereof are preferable, and DBU, DBN, and carboxylates thereof are particularly preferable.

  Although primary or secondary amines have an effect of preventing coloring, primary or secondary amines are not preferred from the viewpoint of the stability of the vinyl polymer (A). In particular, when a vinyl monomer (a-3-i) containing an epoxy group is used as the vinyl monomer constituting the vinyl polymer (A), the viscosity is increased by reaction with the epoxy group.・ This is because gelation may occur.

  The compounding amount of the tertiary amine or organic acid salt (E) thereof is preferably 0.001 to 10 parts by mass, more preferably 0.001 part by mass with respect to 100 parts by mass of the solid content of the vinyl polymer (A). It is good to contain 001-1 mass part. When the component (E) is added in an amount exceeding 10 parts by mass, the thickening of the vinyl polymer (A) in the composition is promoted and the viscosity may be increased. Moreover, there exists a possibility that the coloring prevention effect which the composition anticipated as a compounding quantity is less than 0.001 mass part may not appear.

Next, components that can be optionally added to the coating composition of the present invention will be described.
You may mix | blend a thermoplastic vinyl-type resin with the coating composition of this invention. By blending, it is possible to impart flexibility to the film obtained by curing the coating composition, and to suppress the environmental temperature change that the coating film is subjected to, particularly the phase change and softening phenomenon in a relatively high temperature region. It is possible to suppress the distortion inside the coating film and at the interface with the upper film when laminated, and as a result, it is possible to prevent cracking of the silicon oxide-containing hard film as the upper layer, and the coating film itself has heat resistance and water resistance. Can be granted.
Here, as the thermoplastic vinyl resin, specifically, acrylic resin obtained by (co) polymerization of methyl (meth) acrylate, butyl (meth) acrylate, etc., and acrylic resin obtained by graft modification with polycarbonate or polyester urethane. Resin etc. can be illustrated.

  The amount of the thermoplastic vinyl resin is 0 to 50 parts by mass with respect to 100 parts by mass of the active ingredient in the coating composition (the total amount of the component (A) and the component (B) in terms of solid content). When it mix | blends, it is preferable to set it as 1-50 mass parts, especially 3-45 mass parts. When added in excess of 50 parts by mass, the crosslink density of the coating film is lowered, so that crack resistance and hardness may be lowered.

  An organic ultraviolet absorber may be added to the coating composition as long as it does not cause harmful effects. In this case, an organic ultraviolet absorber having good compatibility with the coating composition is preferable. In particular, compound derivatives whose main skeleton is hydroxybenzophenone, benzotriazole, cyanoacrylate, or triazine are preferable. Furthermore, a polymer such as a vinyl polymer containing these ultraviolet absorbers in the side chain may be used. Specifically, 2,4-dihydroxybenzophenone, 2,2 ′, 4,4′-tetrahydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid, 2 -Hydroxy-4-n-octoxybenzophenone, 2-hydroxy-4-n-dodecyloxybenzophenone, 2-hydroxy-4-n-benzyloxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone 2,2′-dihydroxy-4,4′-diethoxybenzophenone, 2,2′-dihydroxy-4,4′-dipropoxybenzophenone, 2,2′-dihydroxy-4,4′-dibutoxybenzophenone, 2, , 2'-Dihydroxy-4-methoxy-4'-propoxybenzopheno 2,2′-dihydroxy-4-methoxy-4′-butoxybenzophenone, 2,3,4-trihydroxybenzophenone, 2- (2-hydroxy-5-t-methylphenyl) benzotriazole, 2- (2- Hydroxy-5-t-octylphenyl) benzotriazole, 2- (2-hydroxy-3,5-di-t-butylphenyl) benzotriazole, ethyl-2-cyano-3,3-diphenyl acrylate, 2-ethylhexyl- Examples include 2-cyano-3,3-diphenyl acrylate and 2- (2-hydroxy-4-hexyloxyphenyl) -4,6-diphenyltriazine. Two or more of these ultraviolet absorbers may be used in combination.

  The addition amount of the organic ultraviolet absorber is preferably 0 to 30 parts by mass with respect to 100 parts by mass of the active ingredient in the coating composition, and preferably 0.5 to 30 parts by mass when blended. If the amount added is too large, the appearance of the coating film may be whitened or the adhesion to the upper silicon oxide-containing hard film may be lowered.

  In addition, functional metal oxide fine particles may be added as an inorganic ultraviolet absorber within a range that does not adversely affect the coating composition. In this case, what is necessary is just to be compatible with the coating composition and dispersibility, and to maintain a certain transparency without causing the coating to become clouded when formed into a coating. Specifically, titanium oxide, cerium oxide, zinc oxide, tin oxide, zirconium oxide, antimony oxide, tungsten oxide, antimony-containing tin oxide, tin-containing indium oxide, iron oxide, alumina, etc. And fine particles, and mixtures thereof.

  The compounding amount of the metal oxide fine particles is preferably 0 to 30 parts by mass with respect to a total of 100 parts by mass of the active ingredients in the coating composition. When it exceeds 30 mass parts, the transparency of a film may fall.

The manufacturing method of the weather-resistant coating composition of this invention includes the following process as a 1st method.
(I) preparing a coating precursor comprising one or more components excluding the component (E),
(II) A step of adding the component (E) to the coating precursor obtained in the step (I).
However, when there is an unadded component in the step, it is added after the step (II).

First, a coating precursor containing one or more components excluding the component (E) is prepared. Preferably, the components (A), (C) and (D) are mixed to prepare a coating precursor. preferable.
As a method for preparing the coating precursor, one or more components excluding component (E) are mixed and stirred simultaneously or in any order. Stirring may be performed by a known method, but it is preferably performed at 0 to 120 ° C., particularly 20 to 80 ° C., and the time may be sufficient time to be uniform, but usually 5 minutes to 24 hours, In particular, it is 10 minutes to 10 hours.

Next, the component (E) is added to the coating precursor.
When there are remaining components, the weatherable coating composition of the present invention can be obtained by adding the remaining components.

The manufacturing method of the weather-resistant coating composition of this invention includes the following process as a 2nd method.
(III) preparing a coating precursor containing the component (A) alone or the component (A) and one or more components excluding the component (D);
(IV) A step of performing partial hydrolysis by adding water to the coating precursor obtained in the step (III),
(V) A step of adding the component (D) to the coating precursor partial hydrolyzate obtained in the step (IV).
However, when there is an unadded component in the step, it is added after step (V).

  First, the coating precursor containing the component (A) alone or the component (A) and one or more components excluding the component (D) is prepared, preferably the component (A), the component (B) And (C) component, particularly preferably (A) component and (C) component are mixed to form a coating precursor.

Next, water is added to the coating precursor to partially hydrolyze the component (A).
Specifically, the vinyl polymer (A) in which the hydrolyzable silyl group and the organic ultraviolet absorbing group are each bonded to the side chain is hydrolyzed alone to hydrolyze the vinyl polymer (A). A vinyl polymer (A) in which a functional silyl group is converted into a SiOH group, or the hydrolyzable silyl group and the organic ultraviolet absorbing group are bonded to side chains, silica fine particles (B) dispersed in an organic solvent, and carbonyl An organic solvent (C) containing a group, more preferably a vinyl polymer (A) and an organic solvent (C) containing a carbonyl group are mixed to prepare a coating precursor, which is hydrolyzed. Thus, the hydrolyzable silyl group in the coating precursor is converted into a SiOH group. Thereby, when hardening the coating composition of this invention, since it becomes easy to advance bridge | crosslinking and the linear expansion coefficient of a coating layer falls more, it is preferable.

  Hydrolysis of the vinyl polymer (A) in which the hydrolyzable silyl group and the organic ultraviolet absorbing group are bonded to the side chain is performed using water. Water is not particularly limited, but is preferably acidic to neutral. As the substance that makes water acidic, one that does not remain in the coating film when formed into a coating film is preferable. If it remains in the coating film, the expected adhesion and crack resistance may not be obtained. More preferred are organic acids, and specific examples include organic carboxylic acids such as formic acid, acetic acid, propionic acid, and oxalic acid. Of these, formic acid and acetic acid are preferred in consideration of volatility that does not remain in the coating.

  The amount of water used is not particularly limited as long as it is compatible with the coating precursor or the vinyl polymer (A) and becomes uniform. Specifically, the amount of water is preferably less than 5 moles per mole of the hydrolyzable group of the hydrolyzable silyl group in the vinyl polymer (A), and the amount of water is from 0.1 moles to less than 5 moles. Is more preferable, and the amount of water is more preferably 0.3 to 3 mol. If the amount of water used is too large, the storage stability may decrease, and the solution may thicken or gel during storage or use.

The hydrolysis may be carried out by a known method, but is preferably carried out at 0 to 120 ° C. for 0.5 to 24 hours, particularly at 20 to 80 ° C. for 1 to 10 hours.
As a hydrolysis rate by the said hydrolysis, it is preferable that it is 0 to 95%, More preferably, it is 0 to 80%.
In addition, for example, in ¹³ C-NMR analysis, the measurement method includes a peak derived from a methoxysilyl group observed at 50.0 to 50.5 ppm and methanol generated by hydrolysis observed at 49.0 to 49.5 ppm. It can be calculated from the following equation using the integrated value of the peak derived.
Hydrolysis rate (%) = [integral value of methanol-derived peak / (integral value of methanol-derived peak
+ Integral value of peak derived from methoxysilyl group)] × 100
When the hydrolyzable group is not a methoxy group, it can be determined according to this.

  Hydrolysis may be carried out after obtaining a coating precursor containing the vinyl polymer (A) and silica fine particles (B) dispersed in an organic solvent, or the vinyl polymer (A) may be hydrolyzed alone. Alternatively, when hydrolyzed alone, silica fine particles (B) dispersed in an organic solvent are added to the hydrolyzate.

  (D) component is added to the obtained coating precursor partial hydrolysate. And the weather-resistant coating composition of this invention can be obtained by adding the remaining component.

The weather resistant coating composition of the present invention can also be used after diluted with an organic solvent other than the organic solvent (C) containing a carbonyl group. Examples of the organic solvent include propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, isobutyl alcohol, isopropyl alcohol, n-butyl alcohol, n-propyl alcohol, xylene, toluene and the like. It is done.
It is preferable that the weather-resistant coating composition of the present invention is usually diluted with any of the solvents described above and used as a solution having an active ingredient concentration of 5 to 20% by mass.

  Moreover, in order to smooth the coating film, such as Florard FC-4430 (manufactured by Sumitomo 3M Co., Ltd.), KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.), LE-604 (manufactured by Kyoeisha Chemical Co., Ltd.), etc. An effective amount of a fluorine-based, silicone-based, or fluorine-acrylic polymer-based surfactant may be added. In order to accelerate the curing of this coating film, Neostan U-810 (manufactured by Nitto Kasei Co., Ltd.), B-7 (manufactured by Nippon Soda Co., Ltd.), Olga Tix ZA-60, TC-200 (Matsumoto Pharmaceutical Co., Ltd.) A catalytic amount of a cross-linking curing catalyst such as a product of Co., Ltd. may be added.

The obtained weather-resistant coating composition is applied to the surface of a resin substrate such as a previously cleaned plastic film or substrate, and the solvent is evaporated at room temperature or under heating to give a thickness of 0.5 to 30 μm, preferably May form a coating film of 1 to 20 μm. If it is less than 0.5 μm, the desired weather resistance cannot be obtained, and if it exceeds 30 μm, not only the coating property is lowered, but also the mechanical and optical properties inherent to the resin substrate may be lowered. is there.
When evaporating the solvent by heating, it is preferable to heat at a temperature ranging from room temperature to the heat resistant temperature of the substrate, particularly 50 to 140 ° C. for 1 minute to 3 hours, particularly 5 minutes to 2 hours.
The coating method is not particularly limited, and can be performed by roll coating, dip coating, flow coating, bar coating, spray coating, spin coating, or the like.

  The coating composition of the present invention is suitably used for various plastic materials, and in particular, polycarbonate resin, polystyrene resin, (meth) acrylic resin, urethane resin, thiourethane resin, halogenated bisphenol A and ethylene glycol polycondensate, acrylic It is suitably used for urethane resins, halogenated aryl group-containing acrylic resins, sulfur-containing resins, composite laminate materials in which two or more layers of these resins are laminated, and the like.

  A plastic (resin) molded article such as a plastic film or a substrate provided with a cured film by the coating composition of the present invention thus obtained has excellent initial adhesiveness, heat resistance, water resistance, and weather resistance. However, it is preferable to further laminate a known silicon oxide-containing hard film on the coating film because scratch resistance can be imparted.

  Examples of the silicon oxide-containing hard film include a method in which only the surface layer of the film is oxidized and hardened by irradiating the cured film of the coating composition of the present invention with laser or ultraviolet rays, or a vacuum or large amount of an organic silicon compound. Examples thereof include a silicon oxide-containing hard film obtained by a dry method such as atmospheric pressure chemical vapor deposition and a wet method in which a composition containing an organosilane hydrolyzate is applied and cured.

Among them, the following general formula (1)
(R ⁷ ) _m Si (OR ⁸ ) _4-m (1)
(In the formula, R ⁷ represents a monovalent organic group having 1 to 10 carbon atoms, R ⁸ represents a hydrogen atom or a monovalent organic group, and m is 0, 1 or 2.)
A silicon oxide-containing hard coating obtained by a method of obtaining a hard coating by applying one or more hydrolysates or co-hydrolysates of organooxysilane represented by the formula (1) is preferred.

Here, in the above formula (1), the monovalent organic group represented by R ⁷ is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms, such as an alkyl group, an aryl group, a halogenated alkyl group, Halogenated aryl group, alkenyl group, or part of hydrogen atoms of these hydrocarbon groups is substituted with epoxy group, (meth) acryloxy group, mercapto group, amino group, cyano group, etc., and O, NH, Examples include organic groups intervening heteroatoms such as NCH ₃ , specifically, alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, hexyl group, decyl group, cyclohexyl group, Aryl group such as phenyl group, phenethyl group, 3-chloropropyl group, 3,3,3-trifluoropropyl group, 3,3,4,4,5,5,6,6,6-nonafluorohe Halogenated alkyl group such as xyl group, halogenated aryl group such as p-chlorophenyl group, alkenyl group such as vinyl group, allyl group, 9-decenyl group and p-vinylbenzyl group, 3-glycidoxypropyl group, β -(3,4) epoxycyclohexyl) ethyl group, epoxy group-containing organic group such as 9,10-epoxydecyl group, (meth) acryloxy group-containing organic group such as γ-methacryloxypropyl group, γ-acryloxypropyl group Group, γ-mercaptopropyl group, mercapto group-containing organic group such as p-mercaptomethylphenylethyl group, γ-aminopropyl group, amino group-containing organic group such as (β-aminoethyl) -γ-aminopropyl group, β -A cyano group-containing organic group such as a cyanoethyl group can be exemplified.

R ⁸ is a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, and examples of the organic group include an alkyl group, an alkenyl group, an alkoxyalkyl group, and an acyl group, and an alkyl group and an acyl group are preferable. . Specific examples include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a hexyl group, a phenyl group, an isopropenyl group, a methoxyethyl group, and an acetyl group.

Specific examples of silane compounds that satisfy these conditions include:
Methyltrimethoxysilane, methyltriethoxysilane, methyltris (2-methoxyethoxy) silane, methyltriacetoxysilane, methyltripropoxysilane, methyltriisopropenoxysilane, methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane , Vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, vinyltris (2-methoxyethoxy) silane, vinyltriisopropenoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltriacetoxysilane, γ-chloro Propyltrimethoxysilane, γ-chloropropyltriethoxysilane, γ-chloropropyltripropoxysilane, 3,3,3-trifluoropropyltrimethoxy Orchid, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β- (3,4- Epoxycyclohexyl) ethyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethylmethyldimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethylmethyl Diethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-acryloxypropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mer Hept aminopropyltriethoxysilane, N-(beta-aminoethyl)-.gamma.-aminopropyltrimethoxysilane, trialkoxy or triacyloxy silanes such as beta-cyanoethyl trimethoxy silane,
Dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldi (2-methoxyethoxy) silane, dimethyldiacetoxysilane, dimethyldipropoxysilane, dimethyldiisopropenoxysilane, dimethyldibutoxysilane, vinylmethyldimethoxysilane, vinylmethyldiethoxysilane , Vinylmethyldiacetoxysilane, vinylmethyldi (2-methoxyethoxy) silane, vinylmethyldiisopropenoxysilane, phenylmethyldimethoxysilane, phenylmethyldiethoxysilane, phenylmethyldiacetoxysilane, γ-propylmethyldimethoxysilane, γ- Propylmethyldiethoxysilane, γ-propylmethyldipropoxysilane, 3,3,3-trifluoropropylmethyldimethoxysilane, γ-methacryloxy Propylmethyldimethoxysilane, γ-acryloxypropylmethyldimethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethyldiethoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ-mercaptopropylmethyldiethoxysilane, N- Dialkoxysilanes or diacyloxysilanes such as (β-aminoethyl) -γ-aminopropylmethyldimethoxysilane and β-cyanoethylmethyldimethoxysilane;
Furthermore, examples of tetraalkoxysilanes include methyl silicate, ethyl silicate, n-propyl silicate, n-butyl silicate, sec-butyl silicate, t-butyl silicate, and the like.
Bis (trimethoxysilyl) ethane, bis (trimethoxysilyl) hexane, bis (trimethoxysilyl) decane, bis (triethoxysilyl) hexane, bis (trimethoxysilyl) benzene, bis (trimethoxysilyloxydimethylsilyl) benzene Bissilane compounds such as 1,8-bis (trimethoxysilyl) -3,3,4,4,5,5,6,6-octafluorooctane.

  These silane compounds may be (co) hydrolyzed using one or more kinds, and (co) hydrolysates of these silane compounds may be used alone or as a mixture of two or more. it can.

  The (co) hydrolyzate of the silane compound can be obtained, for example, by adding water to a lower alcohol solution of the silane compound in the presence of an acid catalyst to perform hydrolysis. Examples of the lower alcohol include methanol, ethanol, isopropanol, butanol and the like. Examples of solvents that can be used in combination with alcohols include ketones such as acetone, acetylacetone, and cyclohexanone, esters such as ethyl acetate and isobutyl acetate, and ethers such as propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, and diisopropyl ether. The

  Further, colloidal silica obtained by dispersing silica fine particles of 1 to 100 nm in water or a solvent such as methanol, ethanol, isobutanol, propylene glycol monomethyl ether or the like in a (co) hydrolyzate of the above silane compound in a solid content of 5 to 70. A method of applying a colloidal silica-containing organopolysiloxane composition (hard coating composition) added in mass% is more preferred in order to improve the scratch resistance.

  As a method for adding colloidal silica, the colloidal silica may be simply added to the (co) hydrolyzate of the silane compound, or may be hydrolyzed after previously mixing with the silane compound. In the case of water-dispersed colloidal silica, the water in the water-dispersed colloidal silica may be hydrolyzed as part or all of the water necessary for hydrolyzing the silane compound.

In addition, as an ultraviolet absorber that can be added to the (co) hydrolyzate of the silane compound, inorganic oxides include titanium oxide, cerium oxide, zinc oxide, tin oxide, zirconium oxide, antimony oxide, tungsten oxide, and antimony. Tin oxide containing, tin containing indium oxide, iron oxide, silica, single or composite metal oxide fine particles such as alumina, and mixtures thereof; metal chelate compounds such as titanium, zinc, zirconium, etc. (parts thereof) Hydrolysates, condensates; organic compounds such as compound derivatives whose main skeleton is hydroxybenzophenone, benzotriazole, cyanoacrylate or triazine, vinyl polymers containing these UV absorbers in the side chain, etc. (Co) polymers can be mentioned.
Further, as a curing catalyst for the (co) hydrolyzate of the above silane compound, quaternary ammonium salt, alkali metal salt of organic acid, alkoxide and chelate such as aluminum, titanium, chromium and iron, perchlorate, acid anhydride Products, polyamines, Lewis acids and the like may be added in catalytic amounts.

The coating amount of the (co) hydrolyzed product or hard coating composition of the silane compound is preferably applied so that the thickness after heat curing is 0.2 to 20 μm, particularly 0.5 to 15 μm. If it is too thin, the desired hardness and wear resistance may not be obtained. If it is too thick, cracks may occur after curing.
The coating method is not particularly limited, and can be performed by roll coating, dip coating, flow coating, bar coating, spray coating, spin coating, or the like.

  As the curing conditions, when the resin composition is heated and cured at 50 to 140 ° C. for 5 minutes to 3 hours, the coating composition of the present invention is applied to the surface of the plastic molded article. The synergistic effects of the above-described materials provide the advantages of good adhesion and wear resistance and excellent weather resistance.

  The plastic material in which the hard coating of the coating composition of the present invention is coated with a silicon oxide-containing hard coating is excellent in optical properties, weather resistance, and scratch resistance. Therefore, it is preferably used as an optical material or a glass substitute material. be able to.

EXAMPLES Hereinafter, although a synthesis example, an Example, and a comparative example are shown and this invention is demonstrated concretely, this invention is not restrict | limited to the following Example. In addition, in the following example,% shows the mass% and a part shows a mass part. Moreover, a viscosity is a value in 25 degreeC measured based on JISZ8803. The water content is a value measured by the Karl Fischer method. The weight average molecular weight was measured by gel permeation chromatography (GPC) based on standard polystyrene. The hydrolysis rate is determined by ¹³ C-NMR analysis, a peak derived from methoxysilyl group observed at 50.0 to 50.5 ppm and a peak derived from methanol generated by hydrolysis observed at 49.0 to 49.5 ppm. Was calculated from the following equation.
Hydrolysis rate (%) = [integral value of methanol-derived peak / (integral value of methanol-derived peak
+ Integral value of peak derived from methoxysilyl group)] × 100

<Synthesis of vinyl polymer (A) in which hydrolyzable silyl group and organic ultraviolet absorbing group are bonded to side chain>
[Synthesis Example 1]
A 2 liter flask equipped with a stirrer, a condenser and a thermometer was charged with 152 g of diacetone alcohol as a solvent and heated to 80 ° C. under a nitrogen stream. Monomer mixed solution (2- [2′-hydroxy-5 ′-(2-methacryloxyethyl) phenyl] -2H-benzotriazole (RUVA-93, manufactured by Otsuka Chemical Co., Ltd.) ) 81 g, 90 g of γ-methacryloxypropyltrimethoxysilane, 256.5 g of methyl methacrylate, 22.5 g of glycidyl methacrylate, 350 g of diacetone alcohol), and 240 g as a polymerization initiator prepared in advance 54 g of a solution in which 2.3 g of 2,2′-azobis (2-methylbutyronitrile) was dissolved in 177.7 g of diacetone alcohol was sequentially added. After reacting at 80 ° C. for 30 minutes, the remaining monomer mixed solution and the remaining polymerization initiator solution were simultaneously added dropwise at 80 to 90 ° C. over 1.5 hours. Furthermore, it stirred at 80-90 degreeC for 5 hours.
The viscosity of the vinyl polymer in which the obtained trimethoxysilyl group and organic ultraviolet absorbing group are bonded to the side chain is 6,120 mPa · s, and the content of the ultraviolet absorbing monomer in the copolymer is The amount of vinyl monomer in which the trimethoxysilyl group was bonded to the side chain via a C—Si bond was 20%. Moreover, the weight average molecular weight by GPC analysis on the basis of standard polystyrene was 66,200. The vinyl polymer thus obtained (diacetone alcohol solution with a solid content concentration of about 40%) is designated as A-1.

[Synthesis Example 2, Comparative Synthesis Example 1]
With the composition shown in Table 1, vinyl polymers A-2 and RA-1 were obtained in the same manner as in Synthesis Example 1.

(note)
MPTMS: γ-methacryloxypropyltrimethoxysilane RUVA-1: 2- [2′-hydroxy-5 ′-(2-methacryloxyethyl) phenyl
] -2H-benzotriazole (RUVA-93, manufactured by Otsuka Chemical Co., Ltd.)
RUVA-2: 2-hydroxy-4- (2-acryloxyethoxy) benzophenone (BP-1A, manufactured by Osaka Organic Chemical Industry Co., Ltd.)
GMA: Glycidyl methacrylate MMA: Methyl methacrylate

<Synthesis of colloidal silica-containing organopolysiloxane composition>
[Synthesis Example 3]
A 2 liter flask equipped with a stirrer, a condenser and a thermometer was charged with 338 g of methyltrimethoxysilane and maintained at 20 ° C. while stirring. Water-dispersed colloidal silica (Snowtex O (average particle size 15 to 20 nm)) 98 g of Nissan Chemical Industries, Ltd., SiO ₂ 20% product) and 230 g of 0.25N acetic acid aqueous solution were added and stirred for 3 hours. Further, after stirring at 60 ° C. for 3 hours, 300 g of cyclohexanone was added, and by-product methanol was distilled off at normal pressure. Next, 300 g of isopropanol, 134 g of an isopropanol solution of 0.25% tetrabutylammonium hydroxide, and 0.5 g of a polyether-modified silicone KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) as a leveling agent are added, and further a non-volatile content (JIS K). 6833) was adjusted with isopropanol so as to be 20%. The viscosity of the colloidal silica-containing organopolysiloxane composition thus obtained was 4.3 mm ² / s, and the weight average molecular weight determined by GPC analysis was 2,300. This is designated colloidal silica-containing organopolysiloxane composition HC-1.

Examples and comparative examples as coating compositions are given below.
[Example 1]
In a 2 liter flask equipped with a stirrer, a condenser and a thermometer, a vinyl polymer A-1 having a hydrolyzable silyl group and an organic ultraviolet absorbing group bonded to the side chain, respectively 400 g of acetone alcohol solution) (solid content 160 g, 100 parts in terms of solid content), colloidal silica (PMA-ST, solid content concentration 30%, dispersed in propylene glycol monomethyl ether acetate as silica fine particles dispersed in an organic solvent, A primary particle size of 10 to 15 nm (manufactured by Nissan Chemical Industries, Ltd.) 133 g [25 parts in terms of solid content], 100 g of diacetone alcohol, and 100 g of propylene glycol monomethyl ether acetate were charged and stirred well while maintaining at 25 ° C. The water content of the obtained coating precursor by Karl Fischer titration was 1,152 ppm. To this, 67 g of ethyl orthoformate [8.8 mol per 1 mol of water] was added, followed by thorough stirring. The color of the coating precursor was light yellow before the addition of ethyl orthoformate, but gradually became dark purple after the addition of ethyl orthoformate. To this colored coating precursor, 0.5 g of tributylamine [0.3 parts in terms of active ingredient] was added to obtain a coating composition P-1. At this time, dark purple changed to pale yellow (FIG. 1).

[Example 2]
In a 2 liter flask equipped with a stirrer, a condenser and a thermometer, a vinyl polymer A-2 having a hydrolyzable silyl group and an organic UV-absorbing group bonded to the side chain, respectively Acetone alcohol solution) 350 g [solid content 140 g, 100 parts in terms of solid content], diacetone alcohol 100 g, propylene glycol monomethyl ether acetate 100 g, and ethyl orthoformate 50 g [as in Example 1, moisture content 1,152 ppm 6.6 moles per mole of water] and stirred well while maintaining at 25 ° C. The color tone of the obtained coating precursor was light yellow. Further, 0.1 g of tributylamine [0.07 part in terms of active ingredient] was added and stirred for 30 minutes at 25 ° C., and then colloidal silica (PMA) dispersed in propylene glycol monomethyl ether acetate as silica fine particles dispersed in an organic solvent. -ST, solid content concentration 30%, primary particle size 10-15 nm, manufactured by Nissan Chemical Industries, Ltd.) 200 g [solid content 60 g, solid content conversion 42.9 parts] was added, and after stirring well, a pale yellow coating composition Product P-2 was obtained.
The thus obtained coating composition P-2 had a viscosity of 67 mm ² / s, a non-volatile content (JIS K 6833) of 24.8%, a water content of 52 ppm, and a hydrolysis rate by ¹³ C-NMR analysis of 0%. It was.
In addition, after the coating composition P-2 was stored at room temperature for 1 day, the surface was cleaned on a polycarbonate resin plate (Iupilon sheet, manufactured by Mitsubishi Engineering Plastics Co., Ltd.) having a thickness of 5 mm and 150 mm × 150 mm. Each was applied and cured at 120 ° C. for 60 minutes to obtain a film having a thickness of 10.7 μm. The coating film thus obtained was used as a test piece, and the results of various physical property evaluations are shown in Table 2.

[Examples 3 to 5 and Comparative Examples 1 to 6]
The same operation as in Example 2 was performed, and a test piece having a coating composition and a film having a thickness of 6 to 7 μm was obtained using the compositions shown in Tables 2 and 3 (in terms of solid content). Tables 2 and 3 also show the results of various physical property evaluations using the coating composition and the test piece.

[Example 6]
In a 2 liter flask equipped with a stirrer, a condenser and a thermometer, 350 g of vinyl polymer A-2 having a hydrolyzable silyl group and an organic ultraviolet absorbing group bonded to the side chain, respectively (solid content 140 g, solid content) 100 parts in terms of conversion], 100 g of diacetone alcohol, 100 g of propylene alcohol monomethyl ether acetate, and colloidal silica (PMA-ST, solid content concentration 30%, dispersed in propylene glycol monomethyl ether acetate as silica fine particles dispersed in an organic solvent, A primary particle size of 10 to 15 nm, manufactured by Nissan Chemical Industries, Ltd.) 200 g [solid content 60 g, solid content conversion 42.9 parts] was charged and stirred well at 25 ° C. To this was added 4.5 g of deionized water [0.5 mol with respect to 1 mol of methoxysilyl group in A-2], and the mixture was stirred at 60 ° C. for 6 hours. After cooling to room temperature, 111 g of ethyl orthoformate [3 mol per 1 mol of deionized water] was added as a dehydrating agent, and 0.1 g of tributylamine [0.07 parts in terms of active ingredient] was added while stirring, and further 25 The mixture was stirred at 0 ° C. for 3 hours to obtain a pale yellow coating composition P-6.
The viscosity of the coating composition P-6 thus obtained was 103 mm ² / s, the non-volatile content (JIS K 6833) was 25.3%, the water content was 668 ppm, and the hydrolysis rate by ¹³ C-NMR analysis was 17%. It was.
In addition, the coating composition P-6 was applied to a polycarbonate resin plate and cured in the same manner as in Example 2 to obtain a coating having a thickness of 12.6 μm. The coating film thus obtained was used as a test piece, and the results of various physical property evaluations are shown in Table 2.

[Example 7]
477.7 g of vinyl polymer A-1 having a hydrolyzable silyl group and an organic ultraviolet absorbing group bonded to the side chain, respectively, in a 2 liter flask equipped with a stirrer, a condenser and a thermometer [solid content: 191 g, 100 parts in terms of solid content], 827.3 g of diacetone alcohol, 187.4 g of propylene glycol monomethyl ether acetate, 138.1 g of ethyl orthoacetate [Assuming that the water content is 1,200 ppm, 8.7 mol], and 0.2 g of DBU octylate [0.1 parts in terms of active ingredient] was added while stirring well at 25 ° C., and the mixture was stirred at 25 ° C. for 30 minutes and dispersed in an organic solvent. Colloidal silica (PGM-ST, solid content concentration 30%, primary particles dispersed in propylene glycol monomethyl ether as fine silica particles Diameter 10 to 15 nm, Nissan Chemical Industries, Ltd.) 112.4 g [solid basis 17.6 parts] was added and stirred for 30 minutes at 25 ° C.. Thereafter, the solid content was adjusted with propylene glycol monomethyl ether so that the nonvolatile content (JIS K 6833) was 12%, to obtain a pale yellow coating composition P-7.
The thus obtained coating composition P-7 had a viscosity of 25.7 mm ² / s, a water content of 83 ppm, and a hydrolysis rate by ¹³ C-NMR analysis of 0%.

  Further, after storing the coating composition P-7 at room temperature for 1 day, a flow coating method was applied to a 5 mm thick, 150 mm × 150 mm thick polycarbonate resin plate (Iupilon sheet, manufactured by Mitsubishi Engineering Plastics Co., Ltd.). And cured at 120 ° C. for 30 minutes to obtain a film having a thickness of 6.3 μm. Further, the colloidal silica-containing organopolysiloxane composition HC-1 prepared in Synthesis Example 3 was applied on the coating film by a flow coating method and cured at 120 ° C. for 1 hour to form a coating film having a thickness of 2.9 μm. Got. The coating film thus obtained was used as a test piece, and the results of various physical property evaluations are shown in Table 4.

[Example 8]
477.7 g of vinyl polymer A-1 having a hydrolyzable silyl group and an organic ultraviolet absorbing group bonded to the side chain, respectively, in a 2 liter flask equipped with a stirrer, a condenser and a thermometer [solid content: 191 g, It was 100 parts in terms of solid content], and 827.3 g of diacetone alcohol was charged and well stirred while maintaining at 25 ° C. To this was added 5.6 g of deionized water [0.7 mol with respect to 1 mol of methoxysilyl group in A-1], and the mixture was stirred for 5 hours while maintaining at 80 ° C. Colloidal silica dispersed in propylene glycol monomethyl ether as fine silica particles dispersed in an organic solvent after cooling to room temperature (PGM-ST, solid content concentration 30%, primary particle size 10 to 15 nm, manufactured by Nissan Chemical Industries, Ltd.) 112. 4 g [17.6 parts in terms of solid content] and 187.4 g of propylene glycol monomethyl ether acetate were charged and stirred for 10 hours while maintaining at 25 ° C. Thereafter, 138.1 g of ethyl orthoformate [3 moles per mole of deionized water] was added as a dehydrating agent, and 0.2 g of DBU octylate [0.1 parts in terms of active ingredient] was added while stirring at 25 ° C. After further stirring at 25 ° C. for 3 hours, the solid content was adjusted with diacetone alcohol so that the non-volatile content (JIS K 6833) was 12% to obtain a pale yellow coating composition P-8.
The thus obtained coating composition P-8 had a viscosity of 30.7 mm ² / s, a water content of 438 ppm, and a hydrolysis rate of 25% by ¹³ C-NMR analysis.

  In the same manner as in Example 7, a colloidal silica-containing organopolysiloxane composition HC-1 was added on the cured coating film (thickness: 6.9 μm) of the composition P-8, and an ultraviolet absorber (UVA-1) was used as an additive. ) Etc. were mixed to obtain a test piece coated (film thickness after curing: 3.0 μm). The results of coating film physical property evaluation at this time are shown in Table 4.

[Examples 9 and 10]
Using the coating compositions P-2 and P-4 obtained in Examples 2 and 4, after adjusting the solid content with propylene glycol monomethyl ether so that the non-volatile content (JIS K 6833) was 12%, In the same manner as in Example 7, a coating laminate film was obtained (coating cured film thickness of Example 9: 6.6 μm, upper layer cured film thickness: 2.7 μm, coating cured film thickness of Example 10: 6. 8 μm, upper layer cured film thickness: 2.7 μm). The physical properties of the coating thus obtained are shown in Table 4.

[Comparative Examples 7 and 8]
Using the coating compositions PR-1 and PR-6 obtained in Comparative Examples 1 and 6, after adjusting the solid content with propylene glycol monomethyl ether so that the non-volatile content (JIS K 6833) was 12%, A coating laminate film was obtained in the same manner as in Example 7 (Coating cured film thickness of Comparative Example 7: 6.4 μm, Upper layer cured film thickness: 2.8 μm, Coated cured film thickness of Comparative Example 8: 7. 0 μm, upper layer cured film thickness: 2.6 μm). Table 5 shows the physical properties of the coating thus obtained.

Of the abbreviations used in the examples and comparative examples, the abbreviations not described in the synthesis examples are as follows.
<(B) Silica fine particles dispersed in an organic solvent>
B-1: Colloidal dispersed in propylene glycol monomethyl ether acetate
Silica (PMA-ST, solid content concentration 30%, primary particle size 10-15 nm
Manufactured by Nissan Chemical Industries, Ltd.)

<(E) Tertiary amine or organic acid salt thereof>
DBU octylate: 1,8-diazabicyclo [5.4.0] undecene-7 and octyl
Salt DBU with acid: 1,8-diazabicyclo [5.4.0] undecene-7

<Additives (alternative to tertiary amines or organic acid salts thereof)>
DMF: N, N-dimethylformamide Tinuvin 400: hydroxyphenyl triazine (Ciba)
Tinuvin 770: Bis (2,2,6,6) tetramethyl-4-piperidyl) Sebake
(Secondary amine type light stabilizer, manufactured by Ciba)

<Ultraviolet absorber>
UVA-1: 15% alcohol-based solvent dispersion of zinc oxide fine particles (ZNAP15WT%,
CAI Kasei Co., Ltd.)
UVA-2: 2,2 ′, 4,4′-tetrahydroxybenzophenone (Seesorb 10)
6, made by Sipro Kasei Co., Ltd.)

In addition, various physical properties in the examples were measured and evaluated by the following methods.
Evaluation is the coating composition of the present invention and its cured film alone (Examples 2 to 6, Comparative Examples 1 to 6), and a laminate obtained by curing and laminating a colloidal silica-containing organopolysiloxane composition on the cured film. Various evaluation was performed about the film | membrane (Examples 7-10, the comparative examples 7 and 8).

(1) Storage stability: The viscosity of the coating composition after storage at 100C for 2 weeks at 40 ° C was measured and evaluated according to the following criteria.
[Storage stability]
○: The difference between the viscosity after 2 weeks and the initial viscosity is less than 20 mm ² / s Δ: The difference between the viscosity after 2 weeks and the initial viscosity is 20 mm ² / s or more and less than 50 mm ² / s ×: The viscosity after 2 weeks And the difference between the initial viscosity and 50mm ² / s or more

(2) Appearance of initial coating film: The coating film appearance is visually observed for a test piece of a cured film alone layer of the coating composition or a laminated film obtained by curing and laminating a colloidal silica-containing organopolysiloxane composition on the cured film layer. Observed.

(3) Primary adhesion: In accordance with JIS K 5400, the test piece was cut into 6 grids of 2 mm intervals vertically and horizontally with a razor blade to make 25 grids, and a commercially available cellophane adhesive tape was well adhered. Thereafter, when the film was peeled off 90 degrees toward the front, the number of grids (X) remaining without peeling off the coating was indicated by X / 25.

(4) Water resistance and water-resistant adhesion: After immersing the test piece in boiling water for 2 hours, the appearance was visually observed and the adhesion test was performed in the same manner as in (3) above.

(5) Scratch resistance test: In accordance with ASTM 1044, a wear wheel CS-10F was mounted with a Taber abrasion tester, and the haze value after 500 rotations under a load of 500 g was measured. Scratch resistance (%) was indicated by (cloudiness value after test) − (cloudiness value before test).

(6) Weather resistance test: using an I-Super UV tester manufactured by Iwasaki Electric Co., Ltd. [black panel temperature 63 ° C., humidity 50% RH, illuminance 50 mW / cm ² , rain 10 seconds / 1 hour for 5 hours] → The test was conducted for 250 hours and 500 hours under the conditions of repeating this cycle, assuming that the black panel temperature was 30 ° C. and the humidity was 95% RH for 1 hour. Before and after the weather resistance test, the degree of yellowing was observed in accordance with JIS K 7103, and the state of weather coating cracking and weather coating peeling was observed visually or under a microscope (magnification 250 times).
[Weather-resistant coating crack]
The appearance of the coating film after the weather resistance test was evaluated according to the following criteria.
○: No abnormality △: Slightly cracked ×: Cracked in the entire coating film [Weather-resistant coating film peeling]
The peeled state of the coating film after the weather resistance test was evaluated according to the following criteria.
○: No abnormality Δ1: Partial peeling between the colloidal silica-containing organopolysiloxane composition layer and the coating composition layer Δ2: Partial peeling between the coating composition layer and the substrate x1: Colloidal silica Whole surface peeling between containing organopolysiloxane composition layer and coating composition layer x2: Whole surface peeling between coating composition layer and substrate

In Examples 2 to 6, when (E) was changed to various tertiary amines or organic acid salts thereof, the color tone of the coating composition was light yellow and no coloring was observed. Comparing Examples 2 to 6 from the viewpoint of viscosity change, DBU octylate (Example 4) and DBU (Example 5) were compared with tributylamine (Examples 2 and 6) and pyridine (Example 3). Also, the storage stability was good, and DBU octylate (Example 4) was the best among them. The physical properties of the coatings on which these coating compositions were applied and cured were at a level with no problem.
On the other hand, in the comparative example 1, tertiary amine or its organic acid salt (E) was not used, and in the comparative examples 2-5, various nitrogen atom containing additives were used instead of (E). As a result, (E) non-use (Comparative Example 1) and N, N-dimethylformamide (Comparative Example 3) and Tinuvin 400 (Triazine, Comparative Example 4) which are not amines are used as additives. The color tone was dark purple and strongly colored, and the coating film was also colored light yellow. In Comparative Example 2 (t-butylamine, primary amine) and Comparative Example 5 [Tinvin 770 (secondary amine type light stabilizer)] using a primary or secondary amine additive instead of (E), the coating Although coloring of the composition could be prevented, it was found that the viscosity change was large and the storage stability was lacking.
In Comparative Example 6, since the vinyl polymer (A) uses RA-1 that does not contain the unit (a-2) of the organic ultraviolet absorbing group, the composition PR-6 is not colored, Although the viscosity change was small, peeling was seen early in the weather resistance test.

Claims (14)

A method for producing a weather-resistant coating composition comprising the following components (A) to (E) and comprising the following steps (I) and (II):
A vinyl polymer (A) in which a hydrolyzable silyl group and an organic ultraviolet absorbing group are bonded to side chains,
Silica fine particles (B) dispersed in an organic solvent,
An organic solvent (C) containing a carbonyl group,
Orthocarboxylic acid ester (D),
A tertiary amine or an organic acid salt thereof (E),
(I) preparing a coating precursor comprising one or more components excluding the component (E),
(II) A step of adding the component (E) to the coating precursor obtained in the step (I).
However, when there is an unadded component in the step, it is added after the step (II). A method for producing a weather-resistant coating composition comprising the following components (A) to (E) and comprising the following steps (III) to (V):
A vinyl polymer (A) in which a hydrolyzable silyl group and an organic ultraviolet absorbing group are bonded to side chains,
Silica fine particles (B) dispersed in an organic solvent,
An organic solvent (C) containing a carbonyl group,
Orthocarboxylic acid ester (D),
A tertiary amine or an organic acid salt thereof (E),
(III) preparing a coating precursor containing the component (A) alone or one or more components excluding the component (D) and the component (A);
(IV) A step of performing partial hydrolysis by adding water to the coating precursor obtained in the step (III),
(V) A step of adding the component (D) to the coating precursor partial hydrolyzate obtained in the step (IV).
However, when there is an unadded component in the step, it is added after step (V).   The amount of water used for hydrolysis is less than 5 moles relative to 1 mole of hydrolyzable groups of the hydrolyzable silyl group in the vinyl polymer (A). Manufacturing method.   The production method according to claim 1, 2 or 3, wherein the orthocarboxylic acid ester (D) is at least one selected from methyl orthoformate, ethyl orthoformate, methyl orthoacetate and ethyl orthoacetate.   The manufacturing method according to any one of claims 1 to 4, wherein the organic solvent (C) containing a carbonyl group is at least one selected from ketones having 3 to 10 carbon atoms and carboxylic acid esters.   A tertiary amine or an organic acid salt thereof (E) is tributylamine, pyridine, 1,8-diazabicyclo [5.4.0] undecene-7, 1,5-diazabicyclo [4.3.0] nonene-5 and It is at least 1 sort (s) chosen from those carboxylate, The manufacturing method of any one of Claims 1-5.   A vinyl polymer (A) in which a hydrolyzable silyl group and an organic UV-absorbing group are bonded to the side chain is a vinyl monomer (a) in which a hydrolyzable silyl group is bonded through a C-Si bond. -1), a vinyl monomer (a-2) having an organic ultraviolet absorbing group, an epoxy group-containing vinyl monomer (a-3-i), and other copolymerizable monomers It is a vinyl polymer obtained by copolymerizing the monomer component which consists of (a-3-ii), The manufacturing method of any one of Claims 1-6 characterized by the above-mentioned.   A vinyl polymer (A) in which a hydrolyzable silyl group and an organic ultraviolet absorbing group are bonded to side chains, silica fine particles (B) dispersed in an organic solvent, an organic solvent (C) containing a carbonyl group, and A method for preventing coloration of a weather-resistant coating composition containing an orthocarboxylic acid ester (D), wherein a tertiary amine or an organic acid salt (E) thereof is added to the composition. A method for preventing coloration of a weather-resistant coating composition.   The method for preventing coloring according to claim 8, wherein the orthocarboxylic acid ester (D) is at least one selected from methyl orthoformate, ethyl orthoformate, methyl orthoacetate and ethyl orthoacetate.   The method for preventing coloring according to claim 8 or 9, wherein the organic solvent (C) containing a carbonyl group is at least one selected from ketones having 3 to 10 carbon atoms and carboxylic acid esters.   A tertiary amine or an organic acid salt thereof (E) is tributylamine, pyridine, 1,8-diazabicyclo [5.4.0] undecene-7, 1,5-diazabicyclo [4.3.0] nonene-5 and The coloring prevention method according to any one of claims 8 to 10, which is at least one selected from those carboxylates.   A vinyl polymer (A) in which a hydrolyzable silyl group and an organic UV-absorbing group are bonded to the side chain is a vinyl monomer (a) in which a hydrolyzable silyl group is bonded through a C-Si bond. -1), a vinyl monomer (a-2) having an organic ultraviolet absorbing group, an epoxy group-containing vinyl monomer (a-3-i), and other copolymerizable monomers It is a vinyl polymer obtained by copolymerizing the monomer component which consists of (a-3-ii), The coloring prevention method of any one of Claims 8-11 characterized by the above-mentioned.   It is formed by laminating a silicon oxide-containing hard coating on the surface of a coating formed by applying and curing the coating composition produced by the method according to any one of claims 1 to 7 on a substrate. Characteristic coated article. The silicon oxide-containing hard coating has the following general formula (1)
(R ⁷ ) _m Si (OR ⁸ ) _4-m (1)
(In the formula, R ⁷ represents a monovalent organic group having 1 to 10 carbon atoms, R ⁸ represents a hydrogen atom or a monovalent organic group, and m is 0, 1 or 2.)
The coated article according to claim 13, wherein the article is formed from a hard coating composition containing one or more hydrolysates or cohydrolysates of organooxysilane represented by formula (II) and silica fine particles.