JPS5923723B2 - Photosensitive resin composition and photosensitive element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a photosensitive resin composition and a photosensitive element.

More specifically, a photosensitive resin composition for forming a protective film having excellent properties that can be used in printed wiring board production, metal precision processing, etc., and a photosensitive resin composition comprising a layer of the composition and a support film supporting the layer. Concerning the sexual element. It is well known that photosensitive elements, ie, layers of substantially dry photosensitive resin compositions on support films, are used as photoresists for producing printed wiring boards.

Furthermore, it is well known that photosensitive resin compositions having excellent properties that can be used as solder masks, resists for chemical plating, etc. are very useful. The main purpose of a solder mask is to limit the soldering area during soldering to prevent solder bridging, etc., to prevent corrosion of bare copper conductors, and to maintain electrical insulation between conductors over a long period of time. It is.

For these purposes, conventionally, thermosetting inks such as epoxy resins or photocuring inks have been screen printed. However, in recent years, the wiring density of printed wiring boards has increased,
It has become difficult to form the solder masks used for this purpose due to the accuracy of screen printing methods. In addition, with the increase in wiring density, the requirements for electrical insulation between conductors have become stricter, and it has begun to be desired that the thickness of the conductor protective film be at least about 20 μm or more. In the screen printing method, the average thickness of the resist that can be formed at one time is at most 30 μm, and the thickness of the thinnest part of the resist formed on the conductor convex portion is 10 μm.
It has to be the following. Although it is possible to thicken the film by repeating printing two or three times, it is actually very difficult due to the printing precision and the complexity of the process.

Therefore, the emergence of a photosensitive element for forming a solder mask is desired. The thickness of the layer of photosensitive resin composition is 20 μm
The above photosensitive elements are useful. Since the conductor thickness of most printed wirings is 18 μm or more, a photosensitive element having a photosensitive resin layer thickness of 40 μm or more is particularly useful. Photosensitive elements for etching or electrolytic plating, which are generally called photosensitive dry films and are used for forming conductor patterns on printed wiring boards, do not have sufficient heat resistance and cannot be used for forming solder masks.

Therefore, proposals have been made for acid-photosensitive resin compositions for photosensitive elements that have good heat resistance and can be used for forming solder masks (for example, JP-A-53-56018, JP-B-Sho. 52-
43092, Special Publication No. 53-44346).

They have excellent heat resistance, which is one of the purposes of the proposal, but when a thick protective film of 40 μm or more is formed,
Cracks occur within 5 cycles in thermal shock tests at 25°C and 65°C. The occurrence of cracks becomes more severe as the film thickness increases. This becomes a major problem when long-term reliability of printed wiring boards must be considered. Some solder masks formed by screen printing have good resistance to cold and thermal shock.

This is mainly because the thickness of the solder mask formed by the screen printing method is 10 to 30 μm. Another reason is that printing inks generally contain large amounts of filler. It is known that the inclusion of a filler contributes to improving cold shock resistance. However, in the case of a photosensitive element, the layer of the photosensitive resin composition must already be substantially dry before irradiation with actinic light and must have some film properties. This means that the layer of the photosensitive resin composition must contain a linear polymer compound for the purpose of imparting film properties. For this reason,
It is difficult to contain a large amount of filler in addition to the linear polymer compound, active photosensitive compound, and sensitizer. Further, as a result of various studies conducted by the present inventors, in the case of a photosensitive element, if the layer of the photosensitive resin composition contains about 10% by weight or more of filler, it is true that the solder mask formed thereby It was found that although the thermal shock resistance was improved, the soldering heat resistance, which is one of the main properties, was reduced, making it impractical.

As compounds for use in photocurable inks for screen printing, various urethane (meth)acrylate compounds (urethane acrylate compounds or urethane methacrylate compounds, hereinafter the same) have been proposed as having excellent heat resistance. However, great difficulties arise when attempting to apply them to the photosensitive elements targeted by the present invention, which, unlike photocurable inks, usually involve imagewise exposure and development. The first difficulty is that many of the urethane (meth)acrylate compounds that have been proposed are either incompatible or incompatible with linear polymer compounds, especially vinyl copolymer linear polymer compounds that are suitable for various properties. The solubility is extremely poor. The second difficulty is that many of the proposed urethane (meth)acrylate compounds are insoluble in the nonflammable solvents used for developing photosensitive elements, especially the 1,1,1-trichloroethane solvent that is most commonly used. That's true.
Japanese Patent Publication No. 51-15733 discloses a urethane (meth)acrylate compound that overcomes these difficulties. However, the composition disclosed therein cannot be used for forming a solder mask due to its flexibility and heat resistance. The object of the present invention is to provide a photosensitive resin composition that can be used in the formation of a solder mask and has excellent heat resistance and cold shock resistance, and a photosensitive resin composition comprising a layer of the composition and a support film that supports the layer. It is to provide elements.

The present invention comprises (a) (b) trimethylhexamethylene diisocyanate, ((d) dihydric alcohol, and (c) (meth)acrylic acid monoester of dihydric alcohol (acrylic acid monoester or methacrylic acid monoester). 20~
75 parts by weight (b) 20 to 75 parts by weight of a linear polymer compound having a glass transition temperature of about 40 to 150° C. and (c) a sensitizer or (and) a sensitizer system that generates free radicals by actinic light. The present invention relates to a photosensitive resin composition containing the following.

Furthermore, the present invention provides (a) (i) trimethylhexamethylene diisocyanate (i) urethane diacrylate obtained by reacting a dihydric alcohol and an acrylic acid monoester or methacrylic acid monoester of a dihydric alcohol. compound or urethane dimethacrylate compound, 20 to 75 parts by weight; (b) a linear polymeric compound having a glass transition temperature of approximately 40 to 15% by weight; The present invention relates to a photosensitive element comprising a layer of a photosensitive resin composition containing a sensitizer or/and a sensitizer system and a support film supporting the layer.

The photosensitive resin composition proposed by the present invention will be described in detail below.

The photosensitive resin composition proposed by the present invention is obtained by reacting (a) trimethylhexamethylene diisocyanate, a dihydric alcohol, and a (meth)acrylic acid monoester of dihydric alcohol. Urethane (meta)
Contains an acrylate compound as an essential component.

As trimethylhexamethylene diisocyanate (a), for example, Veba Chem of West Germany
It is manufactured by Sakai Shoji Co., Ltd., and is known as TMDI in Japan.
The one sold by Co., Ltd. is used.

This is a mixture of 2,2,4-trimethylhexamethylene diisocyanate and 2,4,4-trimethylhexamethylene diisocyanate. (b) and (c)-2
The alcohols include methylene glycol, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol, 1,4-butanediol, 1.) 3-butanediol, 2,3-butanediol, 1・5-pentanediol, 1,6-hexanediol, 1,10-decanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, bis(2
-hydroxyethyl) terephthalate, 2,2-bis(4-hydroxyethoxyphenyl)propane, 2.
Examples include 2-bis(4-hydroxy diethoxyphenyl)propane. As the (meth)acrylic acid monoester of a dihydric alcohol, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, etc. are used. The dihydric alcohol (b) and the dihydric alcohol (c) may be the same dihydric alcohol or different dihydric alcohols.

The resulting urethane di(metate) acquarate compound is represented by formula 1. It is a methylhexamethylene group. n is O or a positive integer, and the reaction product actually obtained is n
It is a mixture of urethane di(meth)acrylate compounds with different values of . When synthesizing the urethane di(meth)acrylate compound of the present invention, the isocyanate equivalent of (a) trimethylhexamethylene diisocyanate, the dihydric alcohol (g), and the (meth)acrylic acid of the dihydric alcohol (c) Trimethylhexamethylene diisocyanate (a), dihydric alcohol (g), and (meth)acrylic acid monoester of dihydric alcohol (c), which are reacted so that the total alcohol equivalents of the acid monoesters are approximately equal. It is preferable to determine the amount of isocyanate equivalent, but it does not matter if the isocyanate equivalent is in slight excess or in short supply with respect to the alcohol equivalent.

When the isocyanate equivalent is in slight excess over the alcohol equivalent, the excess isocyanate groups can be finally reacted with a monohydric alcohol such as methanol to eliminate free isocyanate groups. If the ratio of the alcohol equivalent of the dihydric alcohol to be reacted (1) to the alcohol equivalent of the (meth)acrylic acid monoester of the dihydric alcohol (c) is 1 (however, the trimethylhexamethylene diisocyanate to be reacted is The number average value of n is 1.

When a dihydric alcohol having a large number of constituent carbon atoms is used, the cold shock resistance of the formed solder mask improves, but the heat resistance decreases.

On the other hand, if a dihydric alcohol having a small number of carbon atoms is used, the heat resistance of the formed solder mask will be further improved, but the cold shock resistance will be lowered. The number of carbon atoms constituting the dihydric alcohol (Oki) and Hira is preferably 1 to 23. It is possible to improve the decrease in heat resistance when using a dihydric alcohol having a large number of constituent carbon atoms. That is, the alcohol equivalent of the dihydric alcohol to be reacted (1) is lower than the alcohol equivalent of the (meth)acrylic acid monoester of the dihydric alcohol (3) (however, the isocyanate of trimethylhexamethylene diisocyanate to be reacted is The decrease in heat resistance can be improved by setting the number average value of n to 1 or less. The decrease in cold shock resistance when using a dihydric alcohol having a small number of constituent carbon atoms can be similarly improved.

That is, the alcohol equivalent of the dihydric alcohol to be reacted is greater than the alcohol equivalent of the (meth)acrylic acid monoester of the dihydric alcohol of H → (However, the isocyanate of trimethylhexamethylene diisocyanate to be reacted (The equivalent weight and the total alcohol equivalent weight should be approximately equal.) By setting the number average value of n to 1 or more, it is possible to improve the deterioration of the thermal shock resistance. That is, in consideration of the balance between heat resistance and cold shock resistance, there is a preferable range of the concentration of the (meth)acryloyl group (referring to an acryloyl group or a methacryloyl group, the same applies hereinafter). As a result of various studies by the present inventors, photosensitivity using a urethane di(meth)acrylate compound (mixture) containing a (meth)acryloyl group of 1 x 10-3 to 4.5 x 10-3 equivalent/y It was found that the solder mask formed using the resin composition has an excellent balance of heat resistance and cold shock resistance. Considering the electrolytic corrosion resistance of a printed wiring board whose conductors are protected by a solder mask, the dihydric alcohol to be reacted is as follows:
1,4-butanediol, 1,3-butanediol, 1
・5-pentanediol, 1,6-hexanediol,
Dihydric alcohols that do not contain hydrophilic groups such as ether bonds in their residues, such as 1,4-cyclohexanedimethanol, are preferred. The content of the urethane di(meth)acrylate compound is in the range of 20 to 75 parts by weight from the viewpoint of heat resistance and cold shock resistance. The photosensitive resin composition of the present invention contains as an essential component a linear polymer compound having a glass transition temperature of about 40 to 150°C.

When the glass transition temperature is less than about 40° C., the formed solder mask has low heat resistance.

When the glass transition temperature exceeds about 150'C, urethane di(
The compatibility with the meth)acrylate compound deteriorates, making it impossible to form a layer of the photosensitive resin composition on the support film or substrate. The vinyl copolymerized linear polymer compound is preferable in terms of compatibility with the urethane di(meth)acrylate compound and adhesion between the printed wiring board and the layer of the photosensitive resin composition. Various vinyl monomers can be used as the copolymerization component of the linear polymer compound. Suitable examples of vinyl monomers include methyl methacrylate, butyl methacrylate, ethyl acrylate, styrene, alpha-methylstyrene, vinyltoluene, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxyethyl acrylate. , acrylic acid, methacrylic acid, glycidyl methacrylate, t-butylaminoethyl methacrylate, 2,3-dibromopropyl methacrylate, 3-chloro-2hydroxypropyl methacrylate, acrylamide and acrylonitrile. If flame retardancy is required for the solder mask to be formed, a monomer containing a bromine atom can be used as a copolymerization component. The content of bromine atoms in the linear polymer compound is suitably up to 40% by weight, and if it exceeds 40% by weight, the thermal shock resistance will decrease.

Monomers containing bromine atoms include tripromophenyl (meth)acrylate (tribromophenyl acrylate or tribromophenyl methacrylate);
(same below) is preferred. Tripromophenyl (meth)
As for the amount of copolymerized acrylate, if it is less than 5% by weight, the effect on flame retardancy is not much different from that without copolymerization, and if it exceeds 65% by weight, the cold shock resistance will decrease. Combination use of antimony trioxide is effective for flame retardancy. However, the content of antimony trioxide in the photosensitive resin composition is 5% by weight.
Exceeding this will have a negative effect on the heat resistance of the formed solder mask. The content of the linear polymer compound in the photosensitive resin composition is in the range of 20 to 75 parts by weight from the viewpoint of heat resistance and thermal shock resistance.

The photosensitive resin composition proposed by the present invention contains as an essential component a sensitizer or/and a sensitizer system that generates free radicals by actinic light.

Sensitizers that can be used include substituted or unsubstituted polynuclear quinones, such as 2-ethylanthraquinone, 2-t-
Butylanthraquinone, octamethylanthraquinone,
1,2-benzanthraquinone, 2,3-diphenylanthraquinone, etc., ketone aldonyl compounds such as diacetyl and benzyl, α-ketaldonyl alcohols and ethers such as benzoin, pivalone, α-monohydrocarbon substituted aromatic acyloin Examples include aromatic ketones such as α-phenyl-benzoin, α・α-diethoxyacetophenone, benzophenone, and 4,4′-bisdialkylaminobenzophenone, which may be used alone or in combination. good. Sensitizer systems that can be used include 2, 4, and 5.
Examples include combinations of the -triarylimidazole dimer and 2-mercaptobenzoquinazole, leuco crystal violet, tris(4-diethylamino-2-methylphenyl)methane, and the like. Additionally, additives can be used which do not have photoinitiating properties by themselves, but which, when used in combination with the above-mentioned substances, result in a sensitizer system with better photoinitiating performance as a whole. Examples include tertiary amines such as triethanolamine for benzophenone. These sensitizers or (and) sensitizer systems are
It is preferably contained in an amount of 0.5 to 10% by weight based on a) urethane di(meth)acrylate and (b) linear polymer compound. The photosensitive resin composition of the present invention may further contain other photopolymerizable unsaturated compounds.
Examples of other photopolymerizable unsaturated compounds include trimethylolpropane triacrylate, pentaerythritol triacrylate, and tetraethylene glycol diacrylate. Furthermore, polymerizable unsaturated compounds disclosed in JP-A-53-56018 can also be used.

However, the content of these other photopolymerizable unsaturated compounds is
In view of the balance between heat resistance and cold shock resistance, it is preferably 20% by weight or less based on the above (a) urethane di(meth)acrylate and (b) linear polymer compound,
Particularly preferred is 10% by weight or less. Other photopolymerizable unsaturated compounds may be added to further improve other properties such as solvent resistance and adhesion. Methacrylic acid ester (hereinafter the same) is preferable in order to further improve the adhesion between the formed solder mask and the printed wiring board. As a (meth)acrylic acid ester containing a phosphate group in the molecule, KA manufactured by Nippon Kayaku Co., Ltd.
YAMER (B) series PM-1, PM-2, PA
-1 or PA-2, Hosma-1 M [manufactured by Yushi Products Co., Ltd.]
F] (acid phosphorus oxyethyl methacrylate)
, Phosma-CL8 (3-chloro-2-acidophoxypropyl methacrylate), and the like.

The content of (meth)acrylic acid ester containing a phosphoric acid group in these molecules is 0.0 with respect to the above (a) urethane di(meth)acrylate and (b) linear polymer compound.
1 to 5% by weight is preferred. Furthermore, the photosensitive resin composition of the present invention can further contain other subsidiary components.

Sub-components include thermal polymerization inhibitors, dyes, pigments, soil-promoting agents, etc., and the selection of these is made based on the same considerations as for ordinary photosensitive resin compositions. Next, the photosensitive element proposed by the present invention will be explained in detail below.

The photosensitive element proposed by the present invention can be obtained by forming a layer of the photosensitive resin composition described in detail above on a support film.

The layer of the photosensitive hardened sweetener can be formed on the support film by a conventional method. For example, a photosensitive resin composition is uniformly dissolved in an organic solvent such as methyl ethyl ketone, toluene, or methylene chloride (however, antimony trioxide, pigments, etc. are uniformly dispersed), and this solution is coated on the support film using a knife coating method. , applied by roll coating method etc.
It is done dry. The amount of residual solvent in the photosensitive layer is preferably kept to 2% by weight or less, particularly preferably 1% by weight or less, in order to maintain properties. The support film used in the present invention must have heat resistance and solvent resistance necessary for the production of photosensitive elements, and may be transparent or opaque to actinic light.

Preferred examples include known films such as polyester film and polyimide film. When producing a long photosensitive element, the element is wound into a roll at the final stage of production.

In this case, by using a backside-treated support film using a method known for pressure-sensitive adhesive tapes, etc., the transfer of the photosensitive resin composition layer to the backside of the support film when it is wound into a roll can be avoided. It is possible to prevent this. For the same purpose, such as preventing dust from adhering, it is preferable to laminate a removable cover film on the photosensitive resin composition layer of the element. Examples of removable cover films include:
Polyethylene film, polypropylene film, Teflon film, surface-treated paper, etc. are used. It is sufficient if the adhesive force between the cover film and the cover film is smaller.

The thickness of the layer of the photosensitive resin composition constituting the photosensitive element of the present invention is determined in order to maintain a high degree of electrical insulation between the conductors of the printed wiring board to which it is applied, and to maintain the resolution of the solder mask pattern to be formed. From this point of view, it is preferably 20 to 2001 tm.

Next, an example of how to use the photosensitive element proposed by the present invention will be described. The photosensitive element proposed by the present invention can be easily laminated onto a substrate.

That is, when there is no cover film, the layers are laminated as is, and when there is a cover film, the layers are laminated with heat and pressure while peeling or peeling off the cover film. Heat and pressure lamination can be carried out using an atmospheric pressure laminator well known to printed wiring board manufacturers. When the substrate has irregularities of 10 μm or more, such as a printed wiring board on which conductive wiring lines are formed, it is preferable to laminate under reduced pressure or vacuum. As an apparatus for this purpose, there is a laminating apparatus described in Japanese Patent Application Laid-Open No. 52-52703 or Japanese Patent Publication No. 55-13341.

Exposure and development treatments after lamination can be carried out by conventional methods.

That is, when the support film is opaque to actinic light, after peeling off the support film, it is exposed imagewise through a negative mask using a light source such as a high-pressure mercury lamp or an ultra-high-pressure mercury lamp. Heat treatment at 50° C. to 100° C. before and after exposure is preferred in order to improve the adhesion between the substrate and the photosensitive resin layer.
A solvent such as 1,1,1-trichloroethane is used as the developer.

The use of nonflammable solvents is preferred for safety reasons. The image-like protective film obtained by this method serves as a corrosion-resistant film for ordinary etching, plating, etc.
Heat treatment at ℃ and exposure to actinic light result in a protective film with even better properties.

The heat treatment after development and the exposure to active light may be carried out in any order, and each may be carried out several times. The protective film obtained by heat treatment after development and exposure to active light has sufficient resistance to organic solvents such as tricrene, methyl ethyl ketone, isopropyl alcohol, and toluene.
Resistant to acidic or alkaline aqueous solutions. Furthermore, since it has excellent heat resistance and cold shock resistance, it is suitable as a permanent protective coating for solder masks and the like that require long-term reliability. Alternatively, a solution of the photosensitive resin composition proposed by the present invention may be applied directly to a substrate by a dip coating method, a flow coating method, etc., and after drying with a solvent, either directly or after laminating a film transparent to active light such as a polyester film, In the same manner as in the case of the photosensitive element, a protective film with excellent properties can be obtained by imagewise exposure through a negative mask, development, further heat treatment and exposure to actinic light. .

Since the coating formed using the photosensitive resin composition or photosensitive element of the present invention has excellent chemical and physical properties, it can also be used for printing plate materials, plastic reliefs, etc.

EXAMPLES Next, examples of the present invention will be shown. The examples shown here are illustrative of embodiments of the present invention, and the present invention is not limited thereto.

"Parts" in Examples and Comparative Examples indicate parts by weight.

Example 1 (a) Synthesis of urethane diacrylate compound The above A is equipped with a thermometer, a stirring device, a cooling tube, a nitrogen gas introduction tube, and a dropper, and has a capacity of about 5 f that can be heated and cooled!
was added to the reactor and the temperature was raised to 60°C while stirring.

B was uniformly added dropwise over about 3 hours while maintaining the reaction temperature at 55 to 65°C. After dropping B, the temperature was maintained at 55 to 65°C for about 2 hours, and then C was uniformly dropped at a temperature of 55 to 65°C over about 3 hours. After C was added dropwise, the reaction temperature was gradually raised to 80° C. over about 5 hours. Then lower the temperature to 60℃,
D was added and stirring was continued for about 1 hour. In this way, a solution of a urethane diacrylate compound with a nonvolatile content of 70% (
1) was obtained. ,) Manufacture of photosensitive element A solution of the photosensitive resin composition was prepared according to the above formulation, and applied onto a polyimide film with a thickness of approximately 50 μm. 20 minutes at room temperature, 10 minutes at 80°C, and 5 minutes at 105°C. After drying, a photosensitive element having a photosensitive resin composition layer thickness of about 60 μm was obtained.

-:) Formation of solder mask Six test boards having the copper pattern shown in Fig. 1 were obtained by imagewise etching a glass epoxy copper clad laminate with a base material thickness of 1.6 mm and a copper foil thickness of 18 μm. Ta.

1 indicates the copper pattern portion, 2 indicates the exposed portion of the base material, and the numerical unit is Mu.

The photosensitive element obtained in (b) above was laminated on this test substrate using an A-500 normal pressure laminator manufactured by Akebono Sangyo Co., Ltd. After lamination, the polyimide film of the support film was peeled off, and a test negative mask shown in Figure 2 was used to remove the polyimide film from the support film.
Exposure was carried out at 900 mJ//Cd using a Phoenix 3000 type exposure machine manufactured by Oak Seisakusho. 3 indicates an opaque portion of the negative mask, and 4 indicates a transparent portion of the negative mask, and the unit of the number is Mm.

After being left for 30 minutes after exposure, spray development was carried out at 20° C. for 90 seconds using 1.1.1=trichloroethane. After development, the film was dried by heating at 80° C. for 10 minutes, and irradiated with 2.5 J/Cd using an ultraviolet irradiation device manufactured by Toshiba Electric Materials Corporation. Thereafter, it was heat-treated at 150°C for 30 minutes.

Four of the six test substrates on which protective films were formed in this way were each immersed in isopropanol, toluene, trichlene, or 10% hydrochloric acid aqueous solution at 25°C for 10 minutes, but there was no change in the formed protective films. was also not recognized. The other sheet was immersed in a solder bath at 255 to 265° C. for 30 seconds, but the protective film was stable and no cracking or peeling from the substrate was observed, indicating that it could be used satisfactorily as a solder mask. Furthermore, the remaining test board was soldered for 3 seconds in a solder bath at 255 to 265°C using rosin flux A-226 (manufactured by Tamura Kaken Co., Ltd.), and then soldered using MIL-STD-20.
2E107D Condition B (-65℃, 30 minutes = room temperature within 5 minutes: 125℃, 30 minutes), 50 cycles of thermal shock test were conducted, but there were no cracks in the protective film, indicating long-term reliability. was found to be very good.

Example 2 A solution of a urethane diacrylate compound was obtained using the above formulation in the same manner as in Example 1-(a).

Thereafter, it was dried under reduced pressure to obtain a viscous urethane diacrylate compound (2). ]) Manufacture of photosensitive element Using the apparatus shown in FIG. 3, a solution 10 of the photosensitive resin composition having the above formulation was uniformly applied onto a polyethylene terephthalate film 16 having a thickness of 25 μm, and a hot air convection method at 80 to 100° C. was applied. It was dried in a dryer 11 for about 10 minutes.

The thickness of the layer of the photosensitive resin composition after drying was about 100 μm. On the layer of the photosensitive resin composition, a polyethylene film 17 with a thickness of about 25 μm is further placed as shown in FIG.
was attached as a cover film. In FIG. 3, 5 is a polyethylene terephthalate film drawing roll, 6, 7, 8 are rolls, 9 is a knife, 12 is a polyethylene film drawing roll, 13, 14 are rolls,
15 is a photosensitive element winding roll. c) Formation of solder mask The photosensitive element obtained above was used as a printed wiring board for test 1 (glass epoxy substrate, thickness: 1.5 μm) on which a copper pattern (copper thickness: approximately 70 μm) as shown in FIG. 1 was formed.
6 mm) using a vacuum laminator manufactured by Hitachi Chemical Co., Ltd. (degree of vacuum: 30 mTnHg, lamination temperature: 100° C., lamination speed: 2 m/min) and laminated under heat and pressure.

After lamination, it was heated at 60° C. for 5 minutes, left at room temperature for 3 hours, and then exposed to light at 150 mJ/Cd through the negative mask for Test 1 shown in FIG. 2 in the same manner as in Example 11(c). After exposure, the film was heated at 80 DEG C. for 5 minutes, left at room temperature for 20 minutes, the support film was peeled off, and spray development was carried out at 20 DEG C. for 150 seconds using 1.1.1-trichloroethane.

After development, heat-dry at 80°C for 10 minutes, 3.0J/Crl
i It was irradiated with ultraviolet rays and heat-treated at 130°C for 2 hours.

Test 1 The test substrate on which the protective film was formed was treated with isopropanol, toluene, trichlene, or 10% hydrochloric acid aqueous solution at 25°C in the same manner as in Example 1-(c).
A immersion test was conducted for 0 minutes, but no change was observed in the formed protective film.

Further, a 30-second immersion test was conducted in a solder bath at 255 to 265°C, and no problems were found, indicating that the product had excellent heat resistance.

Furthermore, after the same soldering process as in Example 1-(c), MIL
-STD-202E107D condition Bl5O cycle thermal shock test also showed no cracks in the formed film. Example 3 Using a solution of the photosensitive resin composition with the above formulation, Example 2-
A photosensitive element having a layer of photosensitive resin composition having a thickness of about 80 μm was obtained using the apparatus shown in FIG. 3 in the same manner as in (b).

This photosensitive element was laminated under reduced pressure in the same manner as in Example 2-(c) on a test printed wiring board on which a copper pattern (copper thickness: approximately 50 μm) as shown in FIG. 1 was formed. Furthermore, the same treatment as in Example 2-(c) was carried out to form an image-like protective film on the test substrate soil. The protective film formed is
Isopropanol, toluene, trichlene at 25°C
Methyl ethyl ketone, 10% aqueous hydrochloric acid solution or 10% Na
A 10-minute immersion test in an OH aqueous solution showed no problems, and a 30-second immersion test in a 255-265°C solder bath showed no cracks or peeling from the base material, indicating excellent heat resistance. Furthermore, after the same soldering process as in Example 1-(c), no cracks were generated in the thermal shock test of Bl5O cycle under MIL-STD2O2ElO7D conditions. Upper piston exchange example 1 Urethane diacrylate compound () of Example 2-(b)
The same operations as in Examples 2-(b) and 2-(c) were carried out except that trimethylolpropane triacrylate was used instead.

Part of the finally obtained protective film was observed to be peeled off from the substrate in one 30 second immersion test in a half bath at 255 to 265°C. Furthermore, cracks occurred within 5 cycles in the thermal shock test under MIL-STD-202E107D condition B after the same soldering process as in Example 1-(c). Comparative Example 2 In place of 60 parts of the urethane diacrylate compound () of Example 3, 20 parts of pentaerythritol triacrylate and bisphenol A di(3-acryloxy-2
The same operation as in Example 3 was carried out except that 40 parts of -hydroxypropyl) ester was used.

The finally obtained protective film cracked within 5 cycles in the thermal shock test under MIL-STD2O2ElO7D condition B after the same soldering process as in Example 1-(c). In addition, in a 10 minute immersion test in a 10% aqueous hydrochloric acid solution, part of the protective film was found to be lifted off the substrate. Comparative Example 3 The same operation as in Example 3 was carried out except that a solution of the photosensitive resin composition having the above formulation was used.

The finally obtained protective film had excellent solvent resistance and heat resistance, but after the same soldering treatment as in Example 1-(c), M
A crack occurred within 10 cycles in the thermal shock test under IL-STD-202E107D condition B. Example
4 A solution of a urethane diacrylate compound was obtained using the above formulation in the same manner as in Example 1-(a).

Thereafter, it was dried under reduced pressure to obtain a viscous urethane diacrylate compound (2). (b) Manufacture of photosensitive element and formation of solder mask The same operations as in Example 2-(b) and Example 2-(c) were carried out using the solution of the photosensitive resin composition with the above formulation. Summer.

The finally obtained protective film showed no problems in a 10-minute immersion test in isopropanol, toluene, trichlene, or 10% hydrochloric acid aqueous solution, and was immersed in a solder bath at 255 to 265°C for 30 seconds, but did not show peeling, cracks, etc. No changes were observed. Furthermore, after soldering treatment similar to Example 1(c), MIL-STD2O2ElO7D conditions Bl5
No cracks occurred even in the O-cycle thermal shock test. Further, a protective film was formed on the entire surface of a 0.8 mm thick base material of a printed wiring board MCL-E-68 (UL flame retardant grade 94V-0) manufactured by Hitachi Chemical Co., Ltd. by the same operation as above.
This product satisfied UL's 94V-1 standard. Example of walking
5 A solution of a urethane diacrylate compound was obtained using the above formulation in the same manner as in Example 1-(a).

Thereafter, it was dried under reduced pressure to obtain a viscous urethane diacrylate compound (2). (b) Manufacture of photosensitive element and formation of solder mask using a solution of the photosensitive resin composition with the above formulation (Other operations were the same as in Example 2-(b) and Example 2-(c)) I did this.

The final protective coating was immersed in isopropanol, toluene, trichloride, or 10% hydrochloric acid for 10 minutes without any problems, and was immersed in a solder bath at 255 to 265°C for 30 seconds, but no peeling or cracking occurred. No changes were observed. Further, after the same soldering process as in Example 1-(c), no cracks occurred in one thermal shock test under MIL-STD-202E107D condition B and 50 cycles. In addition, printed wiring board MCL manufactured by Hitachi Chemical Co., Ltd.
A protective film was formed on the entire surface of the 1.6 mm thick base material of -E-68 in the same manner as above. This one is UL 94V-
1 standard was satisfied. Example 6 The same operation as in Example 5(b) was carried out except that 1 part of antimony trioxide was further added to the solution of the photosensitive resin composition of Example 5-(b).

The solvent resistance, heat resistance, and cold shock resistance of the finally obtained protective film were similar to those of Example 5-(b) and were good. In addition, printed wiring board MCL-E manufactured by Hitachi Chemical Co., Ltd.
A protective film was formed on the entire surface of the -68 1.6mT11 thick base material in the same manner as above. This one is UL 94V-
0 standard was satisfied. Example 7 A solution of the urethane dimethacrylate compound was obtained in the same manner as in Example 1-(a).

Thereafter, it was dried under reduced pressure to obtain a viscous urethane dimethacrylate compound (V). (b) Production of photosensitive element and formation of solder mask The same operations as in Example 2-(b) and Example 2-(c) were carried out using the solution of the photosensitive resin composition having the above formulation. .

The finally obtained protective film showed no problems in one 10-minute immersion test in isopropanol, toluene, trichloride, or 10% hydrochloric acid aqueous solution, and was immersed in a solder bath at 255 to 265°C for 30 seconds, but it did not peel off, crack, etc. No change was observed. Furthermore, after soldering treatment similar to Example 1-(c), MIL-STD-202E107D condition B
No cracks occurred even in the 150 cycle thermal shock test. In addition, printed wiring board MCL- manufactured by Hitachi Chemical Co., Ltd.
A protective film was formed on the entire surface of the E-68 1.6 mTfL thick base material in the same manner as above. This one is UL 94V
-1 standard was satisfied. Example 8 A solution of a urethane diacrylate compound was obtained using the above formulation in the same manner as in Example 1-(a).

Thereafter, it was dried under reduced pressure to obtain a viscous urethane diacrylate compound (2). Using the solution of the photosensitive resin composition of the above formulation, a photosensitive element having a layer of the photosensitive resin composition having a thickness of about 50 μm was prepared using the apparatus shown in FIG. 3 in the same manner as in Example 2-(b). Obtained.

-! ) Formation of a solder mask The photosensitive element obtained above was placed on a test printed wiring board on which a copper pattern (copper thickness: approximately 18 μm) as shown in FIG. 1 was formed in the same manner as in Example 2-(c). Lamination was carried out under reduced pressure.

After lamination, it was left at room temperature for 3 hours, and 200 mJ/C was applied through the test negative mask shown in Figure 2 in the same manner as in Example 1-(c).
d. After exposure, the film was heated at 80'C for 5 minutes and left to cool at room temperature for 20 minutes, and the support film was peeled off.
Spray development was performed at 20° C. for 70 seconds using 1,1-trichloroethane. After development, heat dry at 80°C for 30 minutes,
It was further heated at 120°C for 30 minutes and at 150°C for 30 minutes. After cooling for 10 minutes at room temperature, it was irradiated with ultraviolet light at 10 J/Cd and further heat-treated at 130° C. for 2 hours. Example 1-(
A 10-minute immersion test in isopropanol, toluene, trichlene, or 10% hydrochloric acid aqueous solution at 25° C. was conducted in the same manner as in c), but no problems were found.

Further, even in one 30 second immersion test in a solder bath at 255 to 265°C, the protective film did not peel off and the heat resistance was good.

Furthermore, after soldering treatment similar to Example 1-(c), MIL-
No cracks occurred even in the thermal shock test of STD-202E107D condition Bl5O cycle. Even in the cross-cut test, there was no peeling of the protective film, and the adhesion was excellent.
In addition, Hitachi Chemical Co., Ltd.'s seal pongee top board MCL-E-68
A protective film was formed on the entire surface of the 0.8-thick base material by the same operation as above. This product satisfied UL's 94V-1 standard. Comparative Example 4 Example 1-(a) except that 1344 parts (16 equivalents) of hexamethylene diisocyanate was used instead of 1680 parts (16 equivalents) of trimethylhexamethylene diisocyanate in Example 1-(a). A urethane diacrylate compound was synthesized in the same manner.

The produced urethane diacrylate compound (2) was insoluble in toluene, the reaction solvent, and separated into a waxy form as it was produced. The obtained urethane diacrylate compound () was sparingly soluble in methyl ethyl ketone and 1,1,1-trichloroethane, but soluble in acetone and chloroform. A solution of the photosensitive resin composition with the above formulation was applied onto a polyethylene terephthalate film using the apparatus shown in FIG. 3 in the same manner as in Example 2-(b), and dried with hot air. The diacrylate compound () and the copolymer underwent phase separation, and a preferred photosensitive element could not be obtained.

Furthermore, although the copolymers used in Examples 2 to 8 were used, the compatibility was poor as in the above case, and a preferable photosensitive element could not be obtained. As described above in detail in the Examples, the photosensitive element obtained using the photosensitive resin composition of the present invention forms a protective film with excellent heat resistance, cold shock resistance, and solvent resistance, The formed protective film is suitable for solder masks that require long-term reliability.

The above is only one example of the photosensitive resin composition and photosensitive element of the present invention, and naturally, various modifications and usage methods are possible without departing from the spirit of the present invention.

[Brief explanation of the drawing]

Figure 1 is a diagram showing the copper pattern of the test board used in the example, Figure 2 is a diagram showing the test negative mask used in the example, and Figure 3 is a diagram of the photosensitive element manufacturing apparatus used in the example. This is a schematic diagram. Explanation of symbols, 1... Copper pattern part, 2...
... Exposed part of the base material, 3... Opaque part of the negative mask, 4... Transparent part of the negative mask, 5.
...Polyethylene terephthalate film roll, 6, 7, 8...Roll, 9...
... Knife, 10... Solution of photosensitive resin composition,
11...Dryer, 12...Polyethylene film take-out roll, 13, 14...Roll, 15...Photosensitive element winding opening roll, 16. ...Polyethylene terephthalate film, 17...Polyethylene film.

Claims (1)

[Scope of Claims] 1 (a) A product obtained by reacting (a) trimethylhexamethylene diisocyanate, (b) a dihydric alcohol, and (c) an acrylic acid monoester or a methacrylic acid monoester of a dihydric alcohol. Urethane diacrylate compound or urethane dimethacrylate compound 20-75
Parts by weight (b) 20 to 75 parts by weight of a linear polymer compound having a glass transition temperature of about 40 to 150°C; and (c) a sensitizer or (and) a sensitizer system that generates free radicals by actinic light. A photosensitive resin composition comprising: 2. The photosensitive resin composition according to claim 1, wherein the linear polymer compound is a vinyl copolymerized linear polymer compound. 3. The photosensitive resin composition according to claim 1 or 2, wherein the linear polymer compound is a linear polymer compound containing up to 40% by weight of bromine atoms. 4. Claims 1, 2, or 4, wherein the linear polymer compound is a linear polymer compound containing 5 to 65% by weight of tribromophenyl acrylate or tribromophenyl methacrylate as a copolymer composition. The photosensitive resin composition according to item 3. 5. Photosensitivity according to claim 1, 2, 3, or 4, wherein the dihydric alcohol in (b) and (c) is a dihydric alcohol containing 1 to 23 carbon atoms. Resin composition. 6 (b) The dihydric alcohol is selected from the group consisting of 1,4-butanediol, 1,3-butanediol, 1,5-pentanediol, 1,6-hexanediol and 1,4-cyclohexalinemethanol. The photosensitive resin composition according to claim 1, 2, 3, 4, or 5, which is a dihydric alcohol. 7. The acrylic acid monoester or methacrylic acid monoester of dihydric alcohol is a compound selected from the group consisting of hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, and hydroxypropyl methacrylate, Claims 1 and 2 The photosensitive resin composition according to item 2, 3, 4, 5, or 6. 8 Urethane diacrylate compound or urethane dimethacrylate compound is 1 x 10^-^3 to 4.5 x 10^
Claim 1, which is a urethane diacrylate compound or urethane dimethacrylate compound containing -^3 equivalent/g of acryloyl group or methacryloyl group,
The photosensitive resin composition according to item 2, 3, 4, 5, 6, or 7. Claims 1, 2, 3, 4, 5 containing up to 95% by weight of antimony trioxide,
The photosensitive resin composition according to item 6, 7, or 8. 10 (a) (a) trimethylhexamethylene diisocyanate (b) dihydric alcohol and (c) urethane diacrylate compound or urethane diacrylate compound obtained by reacting acrylic acid monoester or methacrylic acid monoester of dihydric alcohol methacrylate compound, 20-75
Parts by weight (b) 20 to 75 parts by weight of a linear polymer compound having a glass transition temperature of about 40 to 150°C; and (c) a sensitizer or (and) a sensitizer system that generates free radicals by actinic light. A photosensitive element comprising a layer of a photosensitive resin composition and a support film supporting the layer. 11. The photosensitive element according to claim 10, wherein the linear polymer compound is a vinyl copolymerized linear polymer compound. 12 Claim 1, wherein the linear polymer compound is a linear polymer compound containing up to 40% by weight of bromine atoms.
The photosensitive element according to item 0 or item 11. 13. Claims 10, 11, or 13, wherein the linear polymer compound is a linear polymer compound containing 5 to 65% by weight of tribromophenyl acrylate or tribromophenyl methacrylate as a copolymer composition. The photosensitive element according to item 12. 14. The photosensitive material according to claim 10, 11, 12, or 13, wherein the dihydric alcohol in (b) and (c) is a dihydric alcohol containing 1 to 23 carbon atoms. sexual element. 15 (b) The dihydric alcohol is selected from the group consisting of 1,4-butanediol, 1,3-butanediol, 1,5-pentanediol, 1,6-hexanediol and 1,4-cyclohexalinemethanol. Claims 10, 11, and 1 which are dihydric alcohols
The photosensitive element according to item 2, item 13, or item 14. 16. Claim 10, wherein the acrylic acid monoester or methacrylic acid monoester of dihydric alcohol is a compound selected from the group consisting of hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, and hydroxypropyl methacrylate. The photosensitive element according to item 11, 12, 13, 14 or 15. 17 Urethane diacrylate compound or urethane dimethacrylate compound is 1 x 10^-^3 to 4.5 x 10
Claims 10 and 1 are compounds containing ^-^3 equivalents/g of acryloyl or methacryloyl groups.
The photosensitive element according to item 1, 12, 13, 14, 15 or 16. 18 Claims 10, 11, 12, 13, 14, 15, 16, or 18, wherein the photosensitive resin composition contains up to 5% by weight of antimony trioxide; 18. Photosensitive element according to item 17. 19 Claims 10, 11, 12, 13, 14, 15, and 16 comprising a peelable cover film laminated on a layer of photosensitive resin composition 19. The photosensitive element according to item 1, item 17, or item 18. 20 Claims 10, 11, and 12, wherein the layer of the photosensitive resin composition has a thickness of 20 to 200 μm.
Section 13, Section 14, Section 15, Section 16, Section 17,
The photosensitive element according to item 18 or 19.