JPH06212146A - Thermally curing anti-fogging composition - Google Patents

Abstract

PURPOSE:To enable the formation of a coating film which long retains excellent anti-fogging properties, adhesiveness, strengths, and appearance at high temp. by compounding a specific monomer with a specific block or graft copolymer. CONSTITUTION:The anti-fogging compsn. is prepd. by compounding at least one monomer (A) selected from monomers having an N-methylol, N-methylol ether, or hydroxyl group with a block or graft copolymer (B) comprising 50-95wt.% hydrophilic polymer part formed from 1-30wt.% component A and 70-99wt.% at least one hydrophilic monomer that is not reactive but copolymerizable with component A and 50-5wt.% hydrophobic polymer part formed from 1-30wt.% vinyl monomer having a sulfo, carboxyl, or phosphate group and 99-70wt.% lower-alkyl (meth)acrylate copolymerizable therewith, and, if necessary, a surfactant (C) in a wt. ratio (based on solid) of component B to component C of (100:0.5)-(100:30).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-curable antifogging composition used when a plastic material to be coated is exposed to a high temperature environment. More specifically, it is applied to instrument covers, instrument viewing windows, lenses of various lamps, etc., and especially when the internal temperature is 60 to 60
The present invention relates to a heat-curable antifogging agent composition applied to the inner surface of a plastic lens or the like in a vehicle lamp mounted on an automobile exposed to a high temperature environment of 140 ° C.

[0002]

2. Description of the Related Art The present inventors have proposed the following antifogging agent for imparting antifogging property to various transparent plastic materials (Japanese Patent Laid-Open No. 2-255854). That is, the first
Is an antifogging agent comprising a block or graft copolymer comprising a hydrophilic polymer portion and a hydrophobic polymer portion and a surfactant. The second is composed of a hydrophobic polymer portion and a hydrophilic polymer portion formed from an acrylamide derivative,
It is an antifogging agent containing a self-crosslinking block or graft copolymer and a surfactant.

Thirdly, it comprises a hydrophobic polymer portion and a hydrophilic polymer portion formed from an acrylamide derivative and hydroxyalkyl (meth) acrylate, and has a self-crosslinking block or graft copolymer and an interface. An antifog agent for polyester containing an activator.

On the other hand, regarding antifogging of plastic materials exposed to a high temperature environment, it is possible to maintain the antifogging property, adhesion, coating strength and coating appearance for an extremely long time even in a high temperature environment. Is required as basic performance.

[0005]

However, in the case of the antifogging agent comprising the block-and-graft copolymer having a specific composition having self-crosslinking property and the surfactant by the present inventors, the normal temperature range is used. The appearance, antifogging property, coating film strength, and adhesiveness in an environment of -20 to less than 60 ° C are maintained for an extremely long period of time. However, in a high temperature environment, ie, 60 to 140
At a temperature of ° C, there is a problem that the antifogging property and the adhesiveness of the antifogging coating film deteriorate with time. Therefore, even under such a high temperature environment, as in a normal environment, development of an antifogging agent composition capable of maintaining the appearance, antifogging property, coating film strength and adhesion for a long period of time is strongly demanded. .

[0006] Therefore, the present inventors examined the cause of the antifogging coating and the adhesiveness of the antifogging coating, particularly under a high temperature environment of 60 to 140 ° C. As a result, when the coating film is placed in a high temperature environment of 60 to 140 ° C., the crosslinking reaction of the antifogging coating film progresses, the crosslinking density increases with time, and the permeation of water into the coating film becomes early. The antifogging property decreased with time because it was lower than

On the other hand, the adhesiveness was lowered because internal stress was accumulated in the coating film due to the progress of the crosslinking reaction with time, and the coating film could not follow the expansion of the plastic material of the base material as the coating object. . It is considered that there are the following two factors that promote the crosslinking reaction of the coating film. That is, the first point is that hydrophilic monomers having a hydroxy group that form the hydrophilic polymer portion of the block or graft copolymer react with each other.

The second point is that the hydrophilic polymer portion has a cross-linking functional group which is any one of a glycidyl group, an N-methylol group, an N-methyl ether group, a carboxyl group and an acid anhydride group. Having a vinyl type monomer and a cross-linking functional group of any one of a glycidyl group, an N-methylol group, an N-methyl ether group, a carboxyl group and an acid anhydride group which constitutes a hydrophobic polymer portion. It relates to a crosslinking reaction with a vinyl type monomer. That is, at the time of forming the antifogging coating film, first, a crosslinking reaction that develops practically possible coating film strength occurs without reaction of all the crosslinking functional groups, and further 60 to 140
That is, the unreacted crosslinking functional group reacts in a high temperature environment of ℃.

The present invention has been made in view of the problems of the prior art as described above, and its purpose is to exhibit excellent antifogging property, adhesion, coating strength and coating appearance. The object of the present invention is to provide a heat-curable antifogging composition whose properties are maintained for a long time even in a high temperature environment.

[0010]

In order to achieve the above object, the heat-curable antifogging agent composition of the first invention of the present invention comprises an N-methylol group and an N-methylolether group. , 1 to 30% by weight of at least one monomer selected from the group consisting of monomers having a cross-linking functional group of any of the hydroxyl groups (Group A) and no reactivity with the monomers of Group A Vinyl type monomer 1 to 30 having a hydrophilic polymer portion formed of 70 to 99% by weight of at least one hydrophilic monomer having copolymerizability and a sulfonic acid group, a carboxyl group or a phosphoric acid group % By weight and a hydrophobic polymer portion formed from 70 to 99% by weight of a lower alkyl (meth) acrylate having a copolymerizability with the vinyl type monomer, the hydrophilic polymer portion and the hydrophobic polymer portion. The weight ratio of the united part is 50/50 Characterized in that it contains a block or graft copolymer is 95/5.

In the heat-curable antifogging agent composition of the second invention, the hydrophilic polymer portion of the block or graft copolymer is at least one monomer selected from the group A. 1 to 30% by weight, 20 to 84% by weight of at least one hydrophilic monomer having no reactivity with the group A monomer and having copolymerizability, and at least one or more lower alkyl (meth) acrylate 15 It is characterized in that it is formed by ˜50% by weight.

Further, the heat-curable antifogging agent composition of the third invention comprises a block or graft copolymer obtained by incorporating a surfactant into the heat-type antifogging agent composition of the first or second invention. The blending ratio with the surfactant is 100: 0.5 in terms of solid content weight ratio.
It is characterized in that it is set to -30.

Next, the present invention will be described in detail in order. First, the block or graft copolymer in the present invention will be described. The hydrophilic polymer portion of the block or graft copolymer is 1 to 30% by weight of at least one monomer selected from the group A, and at least one monomer having no reactivity with the monomer and copolymerizability. Of 70 to 99% by weight of the hydrophilic monomer, or at least one monomer 1 to 30 selected from the group A
% By weight, 20-84% by weight of at least one hydrophilic monomer having no reactivity with the above monomers and having copolymerizability, and 15-50% by weight of at least one lower alkyl (meth) acrylate. To be done.

The amount of at least one monomer selected from Group A is 1 to 30% by weight, and the crosslinking density is adjusted to an optimum value within this range. As a result, temperature range 6
The antifogging property in a high temperature environment of 0 to 140 ° C. can be expressed, the adhesion between the coating film and the substrate can be maintained for a long period of time, and the practical coating film strength can be expressed.
If the amount of this monomer is less than 1% by weight, the cross-linking density of the coating film is insufficient and sufficient coating film strength cannot be obtained. On the other hand, when it exceeds 30% by weight, the crosslink density becomes too high and the antifogging property is deteriorated, and the adhesiveness with the base material in the initial and high temperature environments is also deteriorated.

Next, as the monomer having a cross-linking functional group of the group A, for example, N-methyl (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-butoxymethyl (meth) is used. Acrylamide,
(Meth) acrylic acid hydroxyethyl ester, (meth) acrylic acid hydroxypropyl ester, (meth)
A hydroxy ester of (meth) acrylic acid such as acrylic acid-3-chloro-2-hydroxypropyl ester or the like is used. These monomers and any of the monomers described below can be obtained as commercial products, and those synthesized according to known methods can be used.

Further, the hydrophilic polymer portion is composed of at least one or more monomers selected from the group A and at least one or more hydrophilic monomers having no reactivity with the monomers and having copolymerizability. In the case of the system formed, it is composed of 70 to 99% by weight of at least one hydrophilic monomer described above. On the other hand, at least one monomer selected from the group A, at least one hydrophilic monomer having no reactivity with the monomer and having copolymerizability, and at least one (meth) acryl In the case of a system formed from lower alkyl acid, at least one hydrophilic monomer 2
It is composed of 0 to 84% by weight.

By using this hydrophilic monomer, the excellent antifogging property at the initial stage of the coating film and in the high temperature environment of 60 to 140 ° C. can be maintained for a long period of time, and the heat resistance can be improved. In each component system, if the amount of this monomer is less than 70% by weight or 20% by weight, the antifogging property in the initial and high temperature environments is deteriorated. On the other hand, 99% by weight or 84% by weight
If it exceeds, the penetrating force of water into the coating film becomes too strong, and the coating film strength decreases.

Next, the hydrophilic monomer is a monomer that does not participate in the cross-linking reaction with the functional group of the monomer of group A at all, or has significantly poor reactivity. As this monomer,
For example, (meth) acrylamide, N-methyl (meth)
Acrylamide, N, N-dimethyl (meth) acrylamide, N-ethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, Nn-propyl (meth) acrylamide, N-isopropyl (meth) acrylamide, N, N'-dimethylaminopropyl (meth)
Acrylamide, N, N'-dimethylaminoethyl (meth) acrylamide, diacetone (meth) acrylamide, N- (meth) acryloylpiperidine, N- (meth) acryloylmorpholine, (meth) acrylic acid, itaconic acid, maleic acid, glutacon Acid, aconitic acid,
Alkali metal salts of radically polymerizable unsaturated carboxylic acids such as citraconic acid, mesaconic acid, fumaric acid, tiglic acid, crotonic acid, muronic acid, isocrotonic acid and 3-butenoic acid,
Quaternary ammonium salts derived from (meth) acrylic acid, such as ammonium salts, methacryloyloxyethyltrimethylammonium chloride, 2-hydroxy-3-methacryloyloxypropyltrimethylammonium chloride, methoxyethylene glycol (meth) acrylate (Here, the number of ethylene oxide is 1 to 1
0 is preferable), (meth) acrylic acid ethoxyethylene glycol (here, the number of ethylene oxide is preferably an integer of 1 to 10), (meth) acrylic acid methoxypropylene glycol (here) And the propyl oxide number n is preferably an integer of 1 to 10) (meta)
Acrylic acid lower alkoxy alkylene glycol, mono (2-hydroxyl ethyl methacrylate) acid phosphate, and other (meth) acrylic acid phosphates, (meth) acrylamido-2-methyl-1-propanesulfonic acid Vinyl monomers having a sulfonic acid group such as vinyl sulfonic acid are used.

Further, in the second aspect of the present invention, the hydrophilic polymer portion has a high adhesiveness and coating strength in a high temperature environment.
That is, in order to improve heat resistance, it is necessary to blend at least one kind of lower alkyl (meth) acrylate, which has not been blended conventionally, and the content thereof is 15 to
It is in the range of 50% by weight. If the amount of this monomer is less than 15% by weight, the coating film strength in a high temperature environment of 60 to 140 ° C will be insufficient. On the contrary, when it exceeds 50% by weight, (meta)
Since the lower alkyl alkyl is hydrophobic, the hydrophilicity of the coating film is reduced and the antifogging property in the initial or high temperature environment is reduced.

Lower alkyl (meth) acrylate has a linear or branched alkyl group having 1 to 4 carbon atoms (meth)
A lower alkyl acrylate, for example, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, i-propyl (meth) acrylate, n-butyl (meth) acrylate, ( I-Butyl (meth) acrylate, t-butyl (meth) acrylate and the like are used.

Next, the hydrophobic polymer portion of the block or graft copolymer will be described. The hydrophobic polymer portion is composed of 1 to 30% by weight of a vinyl type monomer having a sulfonic acid group, a carboxyl group or a phosphoric acid group, and 70 to 99% by weight of a lower alkyl (meth) acrylate having a copolymerizability therewith. %. When the vinyl type monomer having a sulfonic acid group, a carboxyl group or a phosphoric acid group is less than 1% by weight, the transparency of the coating film is lowered, and when it exceeds 30% by weight, the adhesion between the coating film and the substrate is low. Is reduced.

Examples of the monomer include (meth) acrylic acid-3-sulfopropyl and (meth) acrylic acid-2.
-Sulfoethyl, 2-acrylamido-2-methylpropanesulfonic acid, (meth) acrylic acid, crotonic acid, itaconic acid, itaconic acid half ester, maleic acid half ester, maleic acid, mono (2- (meth) acryloyloxyethyl) Acid phosphate or the like is used.

Further, the copolymerizable lower alkyl (meth) acrylate is a lower alkyl (meth) acrylate having a linear or branched alkyl group having 1 to 4 carbon atoms. If the blending ratio of this monomer is less than 70% by weight, the adhesion between the coating film and the base material is lowered, and if it exceeds 99% by weight, the transparency of the coating film is lowered. As the monomer, specifically, the lower alkyl (meth) acrylate described above is used.

Next, the weight ratio of the hydrophilic polymer portion to the hydrophobic polymer portion in the block or graft copolymer needs to be 50/50 to 95/5. When the content of the hydrophilic polymer is less than 50% by weight, the hydrophilicity of the block or graft copolymer is lowered, and the interaction between the block or graft copolymer and the surfactant is weakened, resulting in an initial antifogging property. Not only that, the anti-fog durability is reduced. on the other hand,
If the proportion of the hydrophobic polymer portion is less than 5% by weight, the coating film strength and the adhesion to the substrate will be impaired.

The block or graft copolymer comprising a hydrophilic polymer portion and a hydrophobic polymer portion of the present invention can be synthesized by a conventionally known method, but particularly, it is easy to industrially produce and has a wide range of performance. Further, those produced by a radical polymerization method using a polymeric peroxide, a polyazo compound, or a radical copolymerization peroxide as a polymerization initiator are preferable. In this case, as the radical polymerization initiator to be used, a conventionally known compound having two or more peroxy bonds or azo bonds in one molecule and a compound having a radical copolymerizable group and a peroxy group in one molecule are used. As the polymerization method, a usual bulk polymerization method, suspension polymerization method, solution polymerization method, emulsion polymerization method or the like is adopted.

Next, as a typical production example of the block copolymer of the present invention, a polymerization method using polymeric peroxide as a polymerization initiator will be described below. First, by polymerizing a monomer that forms a hydrophilic polymer portion using a polymeric peroxide, a peroxy bond-containing hydrophilic polymer having a peroxy bond introduced into the chain is obtained. When a monomer that forms a hydrophobic polymer portion is added to this and polymerization is performed, the peroxy bond in the hydrophilic polymer chain is cleaved to efficiently obtain a block copolymer.

A radical copolymerizable group-containing peroxide will be described as a polymerization initiator as a typical production example of the graft copolymer of the present invention. First, by containing a peroxy bond by copolymerizing a vinyl-type monomer that forms a hydrophilic polymer with an ordinary free radical polymerization initiator under the condition that the peroxy bond of the radical copolymerizable group-containing peroxide is not cleaved. A hydrophilic copolymer is obtained. Then, under the condition that this peroxy bond is cleaved, a vinyl-type monomer that forms a hydrophobic polymer is added to this, and polymerization is carried out, so that the peroxy bond in the hydrophilic polymer is cleaved, resulting in efficient graft copolymerization. A polymer is obtained. The block or graft copolymer thus synthesized can freely control the molecular weights of the hydrophilic polymer portion and the hydrophobic polymer portion.

Next, a surfactant is blended in the heat-curable antifogging composition of the third invention. This surfactant is generally used, and is one or more surfactants selected from nonionic surfactants, anionic surfactants, cationic surfactants and zwitterionic surfactants. Is. Among these, nonionic surfactants or anionic surfactants are preferable from the viewpoint of the persistence of effects such as antifogging properties, and particularly polyoxyethylene alkylaryl ethers and dialkylsulfosuccinates. The combination is
It is preferable from the viewpoint of antifogging durability and prevention of change in appearance of the coating film.

Examples of the nonionic surfactants include polyoxyethylene higher alcohol ethers such as polyoxyethylene lauryl alcohol, polyoxyethylene lauryl ether and polyoxyethylene oleyl ether, and polyoxyethylene higher alcohol ethers. Polyoxyethylene alkylaryl ethers such as oxyethylene octylphenol, polyoxyethylene nonylphenol, polyoxyethylene acyl esters such as polyoxyethylene glycol monostearate, polypropylene glycol ethylene oxide Adduct, polyoxyethylene sorbitan monolaurate
, Polyoxyethylene sorbitan monostearate and other polyoxyethylene sorbitan fatty acid esters, alkyl phosphates, polyoxyethylene alkyl ether phosphates and other phosphates, sugar
Esters, cellulose ethers and the like are used.

Examples of the anionic surfactant include fatty acid salts such as sodium oleate and potassium oleate, higher alcohol sulfates such as sodium lauryl sulfate and ammonium lauryl sulfate, sodium dodecylbenzenesulfonate, alkylnaphthalenesulfone. Alkylbenzene sulfonates such as sodium acid salts and alkylnaphthalene sulfonates, naphthalene sulfonic acid formalin condensates, dialkyl sulfosuccinates, dialkyl phosphate salts, polyoxyethylene monkeys such as sodium polyoxyethylene alkylphenyl ether sulfate Fate salt or the like is used.

Examples of the cationic surfactants include ethanolamines, laurylamine acetate, amine salts of triethanolamine monoformate, stearamidoethyldiethylamine acetate, lauryltrimethylammonium chloride, stearyltrimethylammonium chloride. , Dilauryl dimethyl ammonium chloride, distearyl dimethyl ammonium chloride,
Quaternary ammonium salts such as lauryl dimethyl benzyl ammonium chloride and stearyl dimethyl benzyl ammonium chloride are used.

Examples of the zwitterionic surfactant include fatty acid type amphoteric surfactants such as dimethylalkyllaurylbetaine and dimethylalkylstearylbetaine, sulfonic acid type amphoteric surfactants such as dimethylalkylsulfobetaine, and alkylglycine. used.

The mixing ratio of these surfactants is a solid content weight ratio, and the block or graft copolymer: surfactant = 1.
00: 0.5 to 30. The blending amount of the surfactant is 0.
If it is less than 5 parts by weight, the long-term antifogging property cannot be obtained, and if it exceeds 30 parts by weight, the water resistance and the strength of the coating film will be low.

The block or graft copolymer and the surfactant may be mixed by dissolving or dispersing the block or graft copolymer in an organic solvent or a mixed solvent of water and an organic solvent or water. A surfactant may be added therein, or the surfactant may be added together with the monomer forming the block or graft copolymer.

The solvent used in this case is water, methanol, ethanol, n-propanol, isopropanol, n-butanol, diacetone alcohol, or another alcohol-based solvent. Methyl cellosolve, ethyl cellosolve,
Butyl cellosolve, methyl carbitol, ethyl carbitol, alcohol ether solvent such as butyl carbitol, ketone solvent such as methyl ethyl ketone, methyl isobutyl ketone, ester solvent such as methyl acetate, ethyl acetate, butyl acetate, benzene, Examples thereof include aromatic hydrocarbon solvents such as toluene and xylene, amide solvents such as formamide and dimethylformamide. Of these, alcohol-based solvents, alcohol ether-based solvents and mixed solvents thereof are particularly suitable.

In the heat-curable antifogging composition of the present invention, various conventional additives such as an ultraviolet absorber, a leveling agent, a curing catalyst and an antioxidant can be blended if necessary.

Next, the antifogging processing using the heat-curable heat-curable antifogging composition of the present invention will be described. That is, a coating film is formed by applying a heat-curable antifogging agent composition to various plastic materials to be processed by a coating means for ordinary paints and heat-curing at a temperature of 70 to 145 ° C. Let it form. By this anti-fog processing, various plastic materials with anti-fog property are given in an actual environment,
Not only the appearance and adhesion of the coating film, but also the antifogging property and the coating film strength can be maintained for an extremely long time.

The coating environment has a relative humidity of 60%.
R. H. The following is preferable. This is because the antifogging agent composition of the present invention is very hydrophilic and has a strong tendency to absorb water. That is, relative humidity 60% R. H. When the coating is applied in an environment exceeding 10 ° C., the appearance tends to be deteriorated due to whitening of the coating film after heat curing. In order to suppress this whitening phenomenon, it is effective to use a part of the solvent that has a low evaporation rate and a low evaporation rate of water when the solvent volatilizes.

As the coating means, the coating means for ordinary paints, that is, roll coating method, spraying method, dipping method, brush coating method, spin coating method, flow coating method, bar coating method. −
Tar law etc. are applied.

[0040]

EXAMPLES The present invention will be specifically described below with reference to Reference Examples, Examples and Comparative Examples. In each example, the number of copies is based on the weight. (Reference Examples 1 to 12, Synthesis of Block Copolymer)
A block copolymer was synthesized as follows by two-step polymerization using a polymeric peroxide represented by The polymerization conditions shown below are such that the charged monomers are almost completely removed at each stage in both the first-stage polymerization for forming the hydrophilic polymer portion and the second-stage polymerization for forming the hydrophobic polymer portion. It is a condition for polymerizing.

First, 100 parts of methyl cellosolve was charged into a reactor equipped with a thermometer, a stirrer and a reflux condenser.
The mixture was heated to 70 ° C. while blowing nitrogen gas into it, and methylcellosolve A part was used. Polymeric peroxide represented by formula 1 B part Monomer having a cross-linking functional group selected from the A group C part Hydrophilic monomer D part A mixed solution containing a lower alkyl (meth) acrylate E part was charged over 2 hours, and a polymerization reaction was further performed for 2 hours (first-stage polymerization). Then, a mixed solution of methyl cellosolve F part, sulfonic acid, vinyl type monomer having carboxyl group or phosphoric acid group G part, lower alkyl (meth) acrylate H part, was added over 30 minutes, and the mixture was heated at 75 ° C. for 5 hours. A polymerization reaction was carried out. The numbers of parts A to H and the results of polymerization are shown in Tables 1 to 3.

[0042]

## STR1 ## - _{[CO (CH 2) 4 COO (} C 2 H 4 O) 3 CO (CH 2) 4 COOO ] ₁₀ - (Reference Example 13 to 20, the synthesis of the graft copolymer) t-butylperoxy methacryloyloxy A graft copolymer was synthesized using royroxyethyl carbonate. The polymerization conditions shown below are such that the charged monomers are almost completely polymerized in each stage of the first-stage polymerization for forming the hydrophilic polymer portion and the second-stage polymerization for forming the hydrophobic polymer portion. It is a condition to be realized. First, 100 parts of methyl cellosolve was charged into the reactor used in Reference Example 1 and heated to 85 ° C. while blowing nitrogen gas, and 33.6 parts of methyl cellosolve and 4.0 parts of t-butylperoxyoctanoate. t-Butylperoxymethacryloyloxyethyl carbonate 2.4 parts Monomer having a cross-linking functional group selected from the group A Part C Hydrophilic monomer D Part lower alkyl (meth) acrylate E Part Was mixed for 2 hours, and the polymerization reaction was further performed for 7 hours (first-stage polymerization). After that, 110
After heating to ℃, a mixture of methyl cellosolve F part, vinyl type monomer having sulfonic acid, carboxy group or phosphoric acid group, G part, lower alkyl (meth) acrylate, H part, was charged over 30 minutes, and 110 ° C. The polymerization reaction was carried out for 7 hours. Tables 4 and 5 show the number of parts C to H and the polymerization results. (Synthesis of Reference Examples 21 to 23 and Random Copolymer) 100 parts of methyl cellosolve was charged into the reactor used in the synthesis of Reference Example 1, heated to 85 ° C. while blowing nitrogen gas, and 36 parts of methyl cellosolve t. -Butylperoxyoctanoate 4 parts Monomer having a cross-linking functional group selected from the group A C part Hydrophilic monomer D part Lower alkyl (meth) acrylate E part Sulfonic acid, carboxy group or phosphoric acid group A mixed solution consisting of the vinyl type monomer F part having OH was charged over 2 hours, and the polymerization reaction was further performed for 9 hours. Table 6 shows the number of parts of C to F and the polymerization result.
It was shown to.

The abbreviations in Tables 1 to 6 have the following meanings: N-MAAm: N-methyl acrylamide DMAAm: N, N'-dimethyl acrylamide ACMO: N-acryloylmorpholine MMA: methyl methacrylate B- QA: 2-hydroxy-3-methacryloyloxypropyl trimethyl ammonium chloride AMPS: (meth) acrylamido-2-methyl-1-
Propanesulfonic acid IBMA: i-butyl methacrylate M20G: methoxydiethylene glycol methacrylate M40G: methoxytetraethylene glycol methacrylate AA: acrylic acid MAA: methacrylic acid SEM: 2-sulfoethyl methacrylate MC: methyl cellosolve Also, polymerization The solid content in the result column indicates% by weight. The viscosity represents the viscosity (poise, P) of the polymerization solution at 25 ° C. The ratio of the hydrophilic polymer portion is the first in the whole polymer.
It represents the ratio (%) of the polymer synthesized by the step polymerization.

[0044]

[Table 1]

[0045]

[Table 2]

[0046]

[Table 3]

[0047]

[Table 4]

[0048]

[Table 5]

[0049]

[Table 6]

(Examples 1 to 18 and Comparative Examples 1 to 9) All the polymers synthesized in Reference Examples 1 to 23 had a solid content of 2
The mixture was diluted with methyl cellosolve to 0% by weight to obtain a heat-curable heat-curable antifogging agent composition as a polymer solution. In addition, a surfactant was further added to the polymer solution to obtain a heat-curable heat-curable antifogging composition.
Tables 7 to 9 show the respective compositional compositions. Next, each composition was treated with relative humidity of 60% so that the dry film thickness was 5 μm.
R. H. It was applied to a substrate using a bar coater under the following environment and heat-cured under each condition. The abbreviations in Tables 7 to 9 have the following meanings. (Surfactant) (a): polyoxyethylene nonylphenyl ether,
NOF NS-212 (b) manufactured by NOF CORPORATION, polyoxyethylene octylphenyl ether, trade name NONION HS-210 (C) manufactured by NOF CORPORATION: sodium n-dodecylbenzenesulfonate,
NOF CORPORATION Nurex R (d): Sodium dioctyl sulfosuccinate, NOF Corporation brand name Lapisol B80 (e): Octadecyltrimethylammonium chloride, NOF Corporation brand name Cation AB ( f): Dimethylalkyl (coconut) betaine, trade name Anon BF (base material) manufactured by NOF CORPORATION PC: Polycarbonate, PMMA: Polymethylmethacrylate (curing condition) (1): 60 minutes at 80 ° C , (2): 30 minutes at 120 ℃, (3)
: 140 ° C for 10 minutes

[0051]

[Table 7]

[0052]

[Table 8]

[0053]

[Table 9]

The physical properties of each of the coating films thus obtained were evaluated by the following evaluation methods. The results are shown in Tables 10-12. (Adhesion) Cross-cut serrate according to JIS D0202
A peel test was performed. That is, 100 cross cuts are made on the surface of the coating film with a cutter knife so as to reach the substrate,
Stick cellophane adhesive tape (Nichiban Co., Ltd.),
The number of crosscuts that were peeled in the direction perpendicular to the adhesive surface and remained without peeling was represented by the following symbols.

(A): 100/100, (b): 30
/ 100, (c): 15/100, (d): 0 /
100 (Coating strength) Changes in the appearance of the coating film left in each environment were visually evaluated.

◯: No change in appearance, ×: Change in appearance (breath test) The coating film left under each environment was placed in a thermostatic chamber at 20 ° C., and the coating film was blown. The cloudiness was visually evaluated.

⊚: No cloudiness at all, ∘: Water droplets wet and spread instantly, △: Some cloudiness is seen, ×: Cloudy over the entire surface (60 ° C. steam test) Coating in a thermostatic chamber at 20 ° C. The membrane was exposed to warm steam at 60 ° C., and the time until it began to become cloudy was measured. In Tables 10 to 12, “≧ 5” means that the time was 5 hours or longer, and “immediately after” means that the cloud was immediately formed.

Next, the environment of the test piece used in each of the above tests is shown below. (A) Initial stage: Physical properties of coating film immediately after heating and drying (B) Moisture resistance: Coating film at 60 ° C. and relative humidity of 98% R.V. H.
Physical properties of coating film after being left in the environment for 500 hours (C) Heat resistance: When coating film is made of polycarbonate 1
90 at 20 ° C. when the base material is polymethylmethacrylate
Table 10 shows the evaluation results in each environment of coating film physical properties (A) to (C) after standing at 1500C for 1500 hours.
The results are shown in Table 12.

[0059]

[Table 10]

[0060]

[Table 11]

[0061]

[Table 12]

As shown in Tables 1 to 12, when the hydrophilic polymer portion of the block or graft copolymer does not include a portion formed of a monomer within a predetermined range (Comparative Example 1, 3, 7), when the hydrophobic polymer portion does not include a portion formed of a monomer in a predetermined range (Comparative Example 8), the weight ratio of the hydrophilic polymer portion to the hydrophobic polymer portion is If it is not within the predetermined range (Comparative Example 2), either the antifogging property, the adhesiveness or the coating film strength is poor. Moreover, when a random copolymer is used (Comparative Examples 4 to 6 and 9), the antifogging property and the adhesiveness are extremely poor.

On the other hand, the heat-curable antifogging agent compositions of the respective examples are excellent in the initial antifogging property,
It does not change its physical properties even if it is left in an environment of 1,500 ° C. or 90 ° C. for 1,500 hours, and has excellent heat resistance. Incidentally, it can be seen that the antifogging property is maintained for a long period of time by using a surfactant together, and that a combination of polyoxyethylene alkyl aryl ethers and dialkyl sulfosuccinate is particularly preferable (for example, Examples 7 and 9). , 17 and Examples 1, 6, 11, 14
Comparison with). When the amount of the surfactant is more than the predetermined amount referred to in the third aspect of the invention, that is, 3.5 parts by weight per 100 parts by weight of the solid content of the block copolymer (Comparative Example 10), the amount of the surfactant in a humidity resistant or heat resistant environment The coating strength and adhesion tend to deteriorate. This is considered to be because the surplus surfactant acts as a plasticizer and floats on the surface of the coating film. (Examples 19 to 21) Next, the effect of relative humidity under the coating environment on the appearance of the coating film was tested. The formulations of the antifogging agent composition used are shown in Table 13. The polymer used here was obtained by diluting the composition of Reference Example 7, which had good results in the tests of Tables 10 to 12, with a mixed solvent of ethyl cellosolve having a slower evaporation rate than methyl cellosolve to a solid content of 20%. Then, a surfactant was added to this to obtain a heat-curable antifogging composition having heat resistance. In Table 13, methyl cellosolve is represented by MC and ethyl cellosolve is represented by EC.

[0064]

[Table 13]

(Examples 22 to 32) The antifogging agent compositions shown in Table 13 were treated at a relative humidity of 40 to 90% R.V. H. Under the coating environment, the coating was applied so that the dry film thickness was 5 μm, and the change in the appearance of the coating film was evaluated by the haze value before and after the coating. The evaluation results are shown in Table 14. The abbreviations described in the base material and curing conditions are the same as above. The evaluation of the coating film appearance was performed according to the following criteria.

◎: Difference in haze value before and after coating is less than 0.5% ○: Difference in haze value before and after coating is 0.5% or more and less than 1.0% Δ: Before and after coating Difference in haze value is 1.0% or more and less than 1.5% x: Difference in haze value before and after coating is 1.5% or more

[0067]

[Table 14]

From the results of Examples 22 to 25 in Table 14, the coating film appearance is good when the relative humidity of the coating environment is 60% or less (particularly Examples 22 and 24). On the other hand, when the relative humidity exceeds 60% (Example 23), the coating film appearance is slightly deteriorated. Further, even when the relative humidity exceeds 60%, when the predetermined amount of ethyl cellosolve is blended as the solvent (Examples 26 to 32), the appearance of the coating film is kept good.

[0069]

As described in detail above, the heat-curable antifogging agent compositions of the first to third inventions have improved antifogging properties and adhesion, especially in a high temperature environment of 60 to 140 ° C. An excellent effect that excellent antifogging properties, adhesion, coating strength and coating appearance are exhibited, and those properties are maintained extremely well for a long period of time even in a high temperature environment and that they have good heat resistance. Play. Further, according to the second aspect of the invention, it is easy to adjust the hydrophilicity and the hydrophobicity, and it is possible to improve the adhesiveness and the coating strength without lowering the antifogging property in a high temperature environment. can get.

Further, according to the third aspect of the invention, the synergistic effect of the surface active agent provides the excellent effect that the antifogging sustainability can be achieved for a long time and the appearance of the coating film can be favorably maintained.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location C08L 53/00 LLW 7308-4J C09D 5/00 PPG 6904-4J

Claims (3)

[Claims] 1. An N-methylol group, N-methylol group
1 to 30% by weight of at least one monomer selected from the group consisting of monomers having a cross-linking functional group of either a ter group or a hydroxyl group (group A), and reactivity with the group A monomer A vinyl-type monomer 1 having a hydrophilic polymer portion formed of 70 to 99% by weight of at least one hydrophilic monomer having no copolymerization property and a sulfonic acid group, a carboxyl group or a phosphoric acid group. To 30% by weight and a hydrophobic polymer portion formed of 70 to 99% by weight of a lower alkyl (meth) acrylate having a copolymerizability with the vinyl-type monomer, and the hydrophilic polymer portion and the hydrophobic polymer portion. A heat-curable antifogging composition comprising a block or graft copolymer in which the weight ratio of the polymerizable polymer portion is 50/50 to 95/5. 2. In the block or graft copolymer, the hydrophilic polymer portion is 1 to 30% by weight of at least one monomer selected from the group A and the hydrophilic polymer portion.
20-84% by weight of at least one hydrophilic monomer having no reactivity with the group of monomers and having copolymerizability, and at least one or more lower alkyl (meth) acrylate 15-
The heat-curable antifogging composition according to claim 1, which is formed by 50% by weight. 3. The heat-curable antifogging composition according to claim 1 or 2, wherein a surfactant is blended, and the blending ratio of the block or graft copolymer and the surfactant is 1 by weight of solid content.
00: 0.5 to 30 The heat-curable antifogging agent composition, characterized in that