TW201539124A - Photosensitive resin composition, dried film, cured product and printed wiring board - Google Patents

Abstract

The purpose of this invention is to provide a photosensitive resin composition resistant to formation of abrasive trace on a cured product, a dried film coated with the composition and dried, a cured product of the composition or the dried film, and a printed wiring board having the cured product. As the solution, this invention provides a photosensitive resin composition characterized by comprising (A) carboxyl-containing resin, (B) urethane (meth)acrylate with 6 or more functional groups, (C) photopolymerization initiator and (D) titanium oxide. The (B) urethane (meth)acrylate with 6 or more functional groups preferably has a weight average molecular weight of 1,500-200,000.

Description

Photosensitive resin composition, dry film, cured product, and printed wiring board

The present invention relates to a photosensitive resin composition, a dry film, a cured product, and a printed wiring board, and more particularly to a photosensitive resin composition which is hard to generate a rubbing trace on a cured product, and which is coated and dried. A dry film, a cured product of the composition or the dry film, and a printed wiring board having the cured product.

By applying the photosensitive resin composition to a substrate such as a printed wiring board and performing photocuring, it is widely used as an insulating layer such as solder resist (for example, Patent Document 1). When the photocurable composition is used as an insulating layer in a printed wiring board on which a light-emitting element such as a light-emitting diode (LED) or an electroluminescence (EL) is mounted, in order to utilize light efficiently, it is often made of high reflectance. It is composed of a white photosensitive resin composition (for example, Patent Document 2).

[Advanced technical literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2005-311233

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2010-160471

When the printed wiring board or the electronic device is manufactured, the printed wiring board is stacked, the printed wiring board is in contact with the transport roller, or the like, the insulating layer such as solder resist provided on the printed wiring board may be in contact with a metal such as copper. Moreover, if the soldering is provided on the wrap-around wiring board, when the component is mounted in an electronic device, it may be surrounded by metal. If the titanium oxide is highly filled in order to obtain a high-reflectance white solder resist, there is a problem that a frictional trace is generated on the solder resist due to contact with the metal during such manufacturing or practical use.

Accordingly, an object of the present invention is to provide a photosensitive resin composition which is less likely to cause abrasion marks on a cured product, a dry film obtained by coating and drying the composition, a cured product of the composition or the dry film, and the like Printed wiring board for hardened materials.

In order to solve the above problems, the inventors of the present invention have found that the photosensitive resin composition contains urethane (meth) acrylate having six or more functional groups, thereby solving the above problems and further completing the present invention. .

In other words, the photosensitive resin composition of the present invention is characterized by comprising (A) a carboxyl group-containing resin and (B) a functional group having 6 or more amino groups. Ethyl methacrylate (meth) acrylate, (C) photopolymerization initiator, and (D) titanium oxide.

In the photosensitive resin composition of the present invention, the weight average molecular weight of the urethane (meth) acrylate having 6 or more functional groups (B) is preferably 1,500 to 200,000.

The photosensitive resin composition of the present invention further preferably contains at least one of a metal hydroxide and a phosphorus compound.

The dry film of the present invention is characterized in that the photosensitive resin composition is applied onto a film and dried.

The cured product of the present invention is characterized in that the photosensitive resin composition or the dry film is cured.

The printed wiring board of the present invention is characterized by having the cured product described above.

According to the present invention, it is possible to provide a photosensitive resin composition which is excellent in resolution and hardenability of a cured product, and which is less likely to cause abrasion marks on a cured product, a dry film obtained by applying the composition and drying the composition, and the composition. Or a cured product of the dry film and a printed wiring board having the cured product.

The photosensitive resin composition of the present invention is characterized by comprising (A) a carboxyl group-containing resin and (B) a urethane (meth) acrylate having a functional group number of 6 or more (hereinafter, simply referred to as "(B) Urethane (A Base) acrylate"), (C) photopolymerization initiator and (D) titanium oxide. The rubbing trace generated by the hardened material is considered to be due to the high hardness of the titanium oxide, so that the metal scraped off by the titanium oxide exposed on the solder resist surface adheres to the solder resist surface due to friction with the metal. In the present invention, it is considered that by blending (B) a urethane (meth) acrylate having 6 or more functional groups, the surface hardness of the cured product is increased, and the titanium oxide exposure due to friction is lowered. Friction marks are less likely to occur (hereinafter also referred to as "excellent scratch resistance"). Further, as another means for improving the surface hardness, it is considered that the amount of the photopolymerization initiator or the photopolymerizable monomer is increased, but the cured product obtained by the photosensitive resin composition of the present invention may be used in such a means. The deteriorated resolution or the folding property of the hardened material is superior. Further, when titanium oxide is filled, the gloss is lowered, but the cured product obtained by the photosensitive resin composition of the present invention has a good gloss. Here, "(meth) acrylate" means the terms collectively referred to as acrylate, methyl acrylate, and the like, and the other similar expressions in this specification are also the same. Hereinafter, each component will be described in detail.

[(A) Resin containing carboxyl group]

As the (A) carboxyl group-containing resin, a resin containing a known carboxyl group can be used. The resin composition can be made into alkali developability by the presence of a carboxyl group. In addition, in view of photocurability or development resistance of the photosensitive resin composition of the present invention, in addition to a carboxyl group, it is preferred to have an ethylenically unsaturated bond in the molecule, but it is possible to have only no ethylenicity. A carboxyl group-containing resin having a saturated double bond is used as the component (A). Ethylene unsaturated Double bonds, preferably acrylic or methacrylic or derivatives derived therefrom. (A) The carboxyl group-containing resin can be used alone or in combination of two or more.

Specific examples of the carboxyl group-containing resin which can be used in the photosensitive resin composition of the present invention include the following compounds (any of an oligomer and a polymer).

(1) a carboxyl group-containing resin obtained by copolymerizing an unsaturated carboxylic acid such as (meth)acrylic acid with a compound containing an unsaturated group such as styrene, α-methylstyrene, lower alkyl (meth) acrylate or isobutylene. .

(2) a diisocyanate such as an aliphatic diisocyanate, a branched aliphatic diisocyanate, an alicyclic diisocyanate or an aromatic diisocyanate, and a carboxyl group-containing diethanol compound such as dimethylolpropionic acid or dimethylolbutanoic acid And a polycarbonate-based polyol, a polyether-based polyol, a polyester-based polyol, a polyolefin-based polyol, a propylene-based polyol, a bisphenol A-based alkylene oxide adduct diol, a phenolic hydroxyl group, and an alcohol A carboxyl group-containing urethane resin obtained by addition polymerization of a diol compound such as a hydroxyl group compound.

(3) a diisocyanate compound such as an aliphatic diisocyanate, a branched aliphatic diisocyanate, an alicyclic diisocyanate or an aromatic diisocyanate, and a polycarbonate polyol, a polyether polyol, a polyester polyol, In the addition polymerization reaction of a diol compound such as a polyolefin-based polyol, a propylene-based polyol, a bisphenol A-based alkylene oxide adduct diol, a phenolic hydroxyl group or an alcoholic hydroxyl group, the urethane is formed. a urethane tree having a carboxyl group at the end of the ester resin fat.

(4) Diisocyanate and bisphenol A epoxy resin, hydrogenated bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, bisxylenol epoxy resin, bisphenol a photosensitive carboxyl group-containing carbamate formed by addition polymerization of a (meth) acrylate or a partial acid anhydride modified product thereof, a carboxyl group-containing diethanol compound, and a diol compound Ethyl resin.

(5) In the resin synthesis of the above (2) or (4), a compound having one hydroxyl group and one or more (meth) acrylonitrile groups in a molecule such as a hydroxyalkyl (meth) acrylate is added, and A terminal (meth) propylene-containing urethane resin containing a carboxyl group.

(6) In the resin synthesis of the above (2) or (4), a molar reactant such as isophorone diisocyanate and pentaerythritol triacrylate is added, and one isocyanate group and one or more (methyl group) are contained in the molecule. A carboxy group-containing urethane resin which is a terminal (meth) propylene compound.

(7) reacting a polyfunctional epoxy resin as described later with (meth)acrylic acid, and adding phthalic anhydride, tetrahydrophthalic anhydride, and hexahydrophthalic acid to the hydroxyl group present in the side chain. A photosensitive resin containing a carboxyl group after a dibasic acid anhydride such as an anhydride. Here, the multifunctional epoxy resin may be solid or liquid.

(8) reacting a hydroxyl group of a bifunctional epoxy resin with a polyfunctional epoxy resin epoxidized with epichlorohydrin and (meth)acrylic acid, and adding a dibasic acid anhydride to the generated hydroxyl group to have a carboxyl group tree fat. Here, the bifunctional epoxy resin may be solid or liquid.

(9) A polyvalent propylene oxide resin to be described later is reacted with a dicarboxylic acid to add a carboxyl group-containing polyester resin of a dibasic acid anhydride to the produced first-order hydroxyl group.

(10) reacting a reaction product obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule with an alkylene oxide such as ethylene oxide or propylene oxide, and a monocarboxylic acid containing an unsaturated group, and reacting the resulting product A photosensitive resin containing a carboxyl group obtained by reacting a substance with a polybasic acid anhydride.

(11) A reaction product obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule with a cyclic carbonate compound such as ethyl carbonate or propylene carbonate, and a monocarboxylic acid containing an unsaturated group, and then obtaining the obtained product A carboxyl group-containing photosensitive resin obtained by reacting the reaction product with a polybasic acid anhydride.

(12) An epoxy compound having a plurality of epoxy groups in one molecule, a compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule such as p-hydroxyphenylethanol, and (meth)acrylic acid And the reaction of the monocarboxylic acid containing an unsaturated group, and the alcoholic hydroxyl group of the obtained reaction product with maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, adipic acid, etc. A carboxyl group-containing photosensitive resin obtained by the reaction of a polybasic acid anhydride.

(13) Further, the resin of any one of the above (1) to (12) is added to a molecule such as a glycidyl (meth) acrylate or an α-methyl propyl propyl (meth) acrylate. A photosensitive resin containing a carboxyl group formed by a compound of one epoxy group and one or more (meth)acryl fluorenyl groups.

The above-mentioned resin containing a carboxyl group is due to the skeleton. Since the polymer has a plurality of carboxyl groups in its side chain, it can be imaged with a dilute aqueous alkali solution.

Further, the acid value of the (A) carboxyl group-containing resin is more desirably in the range of 20 to 200 mgKOH/g, and more preferably in the range of 40 to 150 mgKOH/g. When the acid value of the carboxyl group-containing resin is 20 mgKOH/g or more, the adhesion of the coating film is good, and alkali development is also good. On the other hand, when the acid value is 200 mgKOH/g or less, the dissolution of the exposed portion due to the developing solution is suppressed, and the line is made thinner if necessary, and depending on the case, the exposure portion and the unexposed portion can be suppressed depending on the case. The solution liquid is dissolved and peeled off, and the photoresist pattern is well drawn.

Further, the weight average molecular weight of the (A) carboxyl group-containing resin varies depending on the resin skeleton, but is preferably in the range of 2,000 to 150,000, and further preferably in the range of 5,000 to 100,000. When the weight average molecular weight is 2,000 or more, the non-peeling property is good, and the moisture resistance of the coating film after exposure is good, and the film reduction at the time of development can be suppressed, and the decrease in resolution can be suppressed. On the other hand, when the weight average molecular weight is 150,000 or less, the developability is good and the storage stability is also excellent. The weight average molecular weight can be determined by gel permeation chromatography.

Among the above carboxyl group-containing resins, the polyfunctional epoxy resin used for the synthesis of the above resin has a structure selected from the group consisting of a bisphenol A structure, a bisphenol F structure, a bisxylenol structure, a bisphenol novolak structure, and a bisxylenol structure. In the case of a polyfunctional epoxy resin having a partial structure in a group of diphenolic structures or a hydrogenated compound thereof, or a resin containing a carboxyl group having a urethane structure, low bending and folding resistance of the obtained cured product View It is better to look at it.

Further, among the carboxyl group-containing resins having a urethane structure, as a component having an isocyanate group (including a diisocyanate), a carboxyl group-containing urethane resin obtained by using a diisocyanate having no isocyanate group directly bonded to a benzene ring is used. Since it has less yellow discoloration, is effective for concealing, and has less ultraviolet light absorption, it is preferable because it has an excellent resolution as an alkali developing composition.

The blending amount of the resin containing a carboxyl group (A) is preferably from 5 to 60% by mass, more preferably from 10 to 60% by mass, even more preferably from 15 to 50% by mass, based on the total solids. When the amount is 5 mass% or more, the coating film strength is good. On the other hand, when it is 60% by mass or less, the viscosity of the composition does not become too high, and the coatability and the like are also good.

[(B) urethane (meth) acrylate]

The photosensitive resin composition of the present invention contains (B) urethane (meth) acrylate having 6 or more functional groups. The functional group described herein means an acryl group or a methacryl group. The number of functional groups is preferably from 6 to 15. When it is in the above range, the folding property and the resolution of the coating film can be set to be uniform, and the scratch resistance is further improved.

(B) The urethane (meth) acrylate having 6 or more functional groups has a weight average molecular weight of preferably 1,500 to 200,000. When it is in the above range, the development resistance of the cured portion and the developability of the uncured portion can be made uniform, and the scratch resistance can be further improved. More preferably, it is 1,500 to 40,000.

As (B) urethane (meth) acrylate, capable of Art Resin UN-3320HA, UN-3320HABA, UN-3320HB, UN-3320HC, UN-3320HS, UN-904, UN-901T, UN-905, UN-952, daicel-allnex company EBECRYL220, manufactured by Gensei Industrial Co., Ltd. 5129, 8301, KRM8200, 8200AE, 8452, made by daicel-allnex, CN968, 975 made by Sartomer, U-6LPA, U-10HA, U-10PA, UA-1100H, U-15HA, UA- by Xinzhongcun Chemical Industry Co., Ltd. 53H, UA-33H, etc. (B) The urethane (meth) acrylate can be used alone or in combination of two or more.

The blending amount of the (B) urethane (meth) acrylate is preferably 10 to 200 parts by mass based on 100 parts by mass of the (A) carboxyl group-containing resin. When it is in the above range, it is possible to maintain the contrast between the development resistance of the cured portion and the development of the uncured portion, and the resolution is also excellent. Moreover, the gloss is more excellent. More preferably, it is 10 to 150 mass parts. In addition to the (B) urethane (meth) acrylate, the photosensitive resin composition of the present invention contains a compound (photopolymerizable monomer) having one or more ethylenically unsaturated groups in the molecule.

(B) The urethane (meth) acrylate is preferably not contained in the carboxyl group.

[(C) Photopolymerization initiator]

The photosensitive resin composition of the present invention contains (C) a photopolymerization initiator. As the (C) photopolymerization initiator, an oxime ester photopolymerization initiator selected from the group consisting of an oxime ester group, an alkyl ethyl ketone photopolymerization initiator, and an α-aminoacetophenone photopolymerization can be suitably used. Starting agent, mercaptophosphine oxide photopolymerization initiator, One or more kinds of photopolymerization initiators in the group of the titanocene-based photopolymerization initiator. The above-mentioned oxime ester-based photopolymerization initiator can be completed by a small amount of addition, and can suppress exhaust gas, and therefore has an effect on PCT resistance or crack resistance and is preferable.

Examples of the oxime ester photopolymerization initiator include CGI-325, IRGACURE-OXE01, IRGACURE-OXE02 manufactured by BASF Japan Co., Ltd., N-1919 manufactured by ADEKA Co., Ltd., NCI-831, and the like. Further, a photopolymerization initiator having two oxime ester groups in the molecule can also be suitably used. As the oxime ester photopolymerization initiator, a compound having a carbazole structure is particularly preferable.

The blending amount of the oxime ester-based photopolymerization initiator is preferably 0.01 to 10 parts by mass, more preferably 0.25 to 5 parts by mass, per 100 parts by mass of the (A) carboxyl group-containing resin. By setting it as 0.01 to 10 parts by mass, it is possible to obtain a cured film which is excellent in photocurability and resolution, and which is excellent in adhesion and PCT resistance, and which is excellent in chemical resistance such as electroless gold plating resistance. In particular, when the amount is 5 parts by mass or less, it is possible to suppress a decrease in deep hardenability due to intense light absorption on the surface of the coating film.

The commercially available product of the alkyl ethyl ketone-based photopolymerization initiator is an α-hydroxyalkyl ketone type such as IRGACURE-184, DAROCUR-1173, IRGACURE-2959, and IRGACURE-127 manufactured by BASF Japan.

As the α-aminoacetophenone photopolymerization initiator, specifically, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinylacetone-1,2- Benzyl-2-dimethylamino-1-(4-morphinylphenyl)-butan-1-one, 2-(dimethylamino)- 2-[(4-Benzyl)methyl]-1-[4-(4-ythyl)phenyl]-1-butanone, N,N-dimethylamine acetophenone, and the like. As a commercial item, IRGACURE-907, IRGACURE-369, IRGACURE-379, etc. by BASF Japan Corporation are mentioned.

As the mercaptophosphine oxide photopolymerization initiator, specifically, 2,4,6-trimethylbenzimidyldiphenylphosphine oxide, bis(2,4,6-trimethyl) Benzhydryl)-phenylphosphine oxide, bis(2,6-dimethoxybenzylidene)-2,4,4-trimethyl-pentylphosphine oxide, and the like. As a commercial item, LUCIRIN TPO by BASF Corporation, IRGACURE-819 by BASF Japan, etc. are mentioned.

The blending amount of the α-aminoacetophenone photopolymerization initiator and the mercaptophosphine oxide photopolymerization initiator is 0.1 to 25 parts by mass based on 100 parts by mass of the (A) carboxyl group-containing resin. Preferably, it is preferably from 1 to 20 parts by mass. When it is 0.1 to 25 parts by mass, it is possible to obtain a cured film which is excellent in photocurability and resolution, and which has improved adhesion and PCT resistance, and is excellent in chemical resistance such as electroless gold plating resistance. In particular, when the amount is 25 parts by mass or less, the effect of reducing the exhaust gas is obtained, and further, it is possible to suppress a decrease in deep hardenability due to intense light absorption on the surface of the coating film.

Further, as the photopolymerization initiator, IRGACURE-389 manufactured by BASF Japan can also be used as appropriate. A suitable blending amount of IRGACURE-389 is 0.1 to 20 parts by mass, more preferably 1 to 15 parts by mass, per 100 parts by mass of the carboxyl group-containing resin.

Further, a titanocene-based photopolymerization initiator such as IRGACURE-784 can also be suitably used. Titanocene photopolymerization initiator is more suitable The blending amount is 0.01 to 5 parts by mass based on 100 parts by mass of the resin containing a carboxyl group, and more preferably 0.01 to 3 parts by mass.

By setting such a photopolymerization initiator in a suitable blending amount, it is possible to obtain excellent photocurability and resolution, and also improve adhesion or PCT resistance, and chemical resistance such as electroless gold plating resistance. A hardened material that is also excellent in properties. In addition, when it is an appropriate blending amount, the effect of reducing the exhaust gas is obtained, and further, it is possible to suppress a decrease in deep hardenability due to intense light absorption on the surface of the coating film.

In addition to the photopolymerization initiator, the photosensitive resin composition can also use a photoinitiating aid or a sensitizer. As a photopolymerization initiator, a photoinitiating aid, and a sensitizer which can be suitably used in a photosensitive resin composition, a benzoin compound, an acetophenone compound, a leek compound, a thioxanthone compound, a ketal can be exemplified. A compound, a diphenyl ketone compound, a tertiary amine compound, an oxonone compound, or the like.

These photopolymerization initiators, photoinitiating aids, and sensitizers can be used alone or in combination of two or more. The total amount of the photopolymerization initiator, the photoinitiator, and the sensitizer is preferably 35 parts by mass or less based on 100 parts by mass of the (A) carboxyl group-containing resin. When it is 35 parts by mass or less, it is possible to suppress a decrease in deep hardenability due to such light absorption.

[(D) Titanium oxide]

The (D) titanium oxide may be rutile-type titanium oxide or anatase-type titanium oxide, but rutile-type titanium oxide is preferably used. Also oxidized Titanium anatase-type titanium oxide has a higher whiteness than rutile-type titanium oxide, and is often used as a white pigment. However, since anatase-type titanium oxide has photocatalytic activity, it is sometimes because of LED The irradiated light causes discoloration of the resin in the photosensitive resin composition. On the other hand, although the whiteness of the rutile-type titanium oxide is slightly inferior to that of the anatase type, since it has almost no photoactivity, the resin caused by the light activity of the titanium oxide can be remarkably suppressed. Deterioration (yellow discoloration) and stability to heat. Therefore, when used as a white pigment in the insulating layer of the printed wiring board on which the LED is mounted, it is possible to maintain a high reflectance for a long period of time.

As the rutile-type titanium oxide, a well-known person can be used. In the method for producing rutile-type titanium oxide, there are two types of sulfuric acid method and chlorine atom method, and those manufactured by any of the methods can be suitably used in the present invention. Here, the sulfuric acid method means that ilmenite ore or titanium slag is used as a raw material, this is dissolved in concentrated sulfuric acid, and the iron portion is separated as iron sulfate, and the solution is hydrolyzed, thereby obtaining a precipitate of hydroxide. This is a method of producing rutile-type titanium oxide by firing at a high temperature. On the other hand, the chlorine atom method means that synthetic rutile or natural rutile is used as a raw material, and this is reacted with chlorine and carbon at a high temperature of about 1000 ° C to synthesize titanium tetrachloride, which is then oxidized and taken out of rutile. Method for preparing titanium oxide. Among them, the rutile-type titanium oxide produced by the chlorine atom method is particularly effective in suppressing resin deterioration (yellow discoloration) caused by heat, and is more suitably used in the present invention.

Among these titanium oxides, titanium oxide whose surface is treated with aqueous alumina or aluminum hydroxide can be used, but it is particularly preferable from the viewpoints of dispersibility, storage stability, and flame retardancy in the composition.

Further, the cured product formed of the photosensitive resin composition of the present invention preferably has a Y value of 65 or more, and is preferably 70 or more.

(D) The blending amount of the titanium oxide is preferably 30 to 300 parts by mass, more preferably 50 to 250 parts by mass, per 100 parts by mass of the resin containing the carboxyl group (A). (D) The titanium oxide may be used alone or in combination of two or more. Further, other coloring agents other than titanium oxide may be contained within a range that does not impair the effects of the present invention.

(D) The titanium oxide may also be a surface treated with cerium oxide or aluminum oxide.

The titanium oxide surface-treated with cerium oxide can suppress deterioration of light. The titanium oxide treated with alumina surface can further increase the reflectance of the cured product. The titanium oxide surface-treated with cerium oxide or aluminum oxide may be an anatase type or a rutile type, but is preferably a rutile type. Further, among the rutile-type titanium oxides, those produced by the chlorine atom method can further suppress the deterioration of the resin, which is particularly preferable.

As a titanium oxide surface treated with cerium oxide or aluminum oxide, Tipaque R-930, Tipaque R-630, Tipaque R-680, Tipaque R-670, Tipaque CR-50, Tipaque CR-57, Tipaque CR-97 can be used. , Tipaque CR-60, Tipaque CR-63, Tipaque CR-67, Tipaque CR-58, Tipaque UT771, Tipaque R-820, Tipaque R-830, Tipaque R-550, Tipaque R-780, Tipaque R-780-2 , Tipaque R-850, Tipaque R-855, Tipaque CR-80, Tipaque CR-90, Tipaque CR-90, Tipaque CR-90-2, Tipaque CR-93, Tipaque CR-95, Tipaque CR- 953, Tipaque CR-63, Tipaque CR-85 (made by Ishihara Sangyo Co., Ltd.), Taipyua R-100, Taipyua R-101, Taipyua R-102, Taipyua R-103, Taipyua R-104, Taipyua R-105, Taipyua R -108, Taipyua R-900, Taipyua R-902, Taipyua R-960, Taipyua R-706, Taipyua R-931 (manufactured by Du Pont), TITON R-25, TITON R-21, TITON R-32, TITON R-7E, TITON R-5N, TITON R-61N, TITON R-62N, TITON R-42, TITON R-45M, TITON R-44, TITON R-49S, TITON GTR-100, TITON GTR-300, TITON D-918, TITON TCR-29, TITON TCR-52, TITON FTR-700 (manufactured by Suga Chemical Co., Ltd.), TITANIX JR-300, TITANIX JR-403, TITANIX JR-405, TITANIX JR-600A, TITANIX JR-600E TITANIX JR-602, TITANIX JR-602S, TITANIX JR-603, TITANIX JR-805 (manufactured by Tayca).

Further, examples of the anatase-type titanium oxide include Tipaque A-220 (manufactured by Ishihara Sangyo Co., Ltd.) and TITANIX JA-4 (manufactured by Tayca Co., Ltd.).

The titanium oxide surface-treated with titanium oxide can be further subjected to other surface treatments after being treated with an alumina surface. In particular, after further treatment with zirconia after the surface treatment with alumina, the reflectance can be further improved.

In the above-mentioned titanium oxide, Tipaque CR-57, Tipaque CR-97, Tipaque CR-67 (manufactured by Ishihara Sangyo Co., Ltd.), and R-61N are mentioned as the titanium oxide surface-treated with zirconia. , GTR-100, GTR-300 (made by 堺Chemical Industries, Inc.), TITANIX JR- 603 (made by Tayca Corporation).

(flammable agent)

The photosensitive resin composition of the present invention preferably contains a conventionally known flame retardant for the purpose of improving the flame retardancy of the obtained cured product. From the viewpoint of the environment, it is preferred to use a flame retardant which does not contain a halogen. As the flame retardant, for example, aluminum hydroxide, magnesium hydroxide, hydrotalcite, and diaspore, which contain a phosphorus-containing compound or an inorganic filler which imparts flame retardancy to the resin composition, may be blended. Among the flame retardants, a compound containing phosphorus and a metal hydroxide are preferable. The flame retardant can be used singly or in combination of two or more.

As the compound containing phosphorus, those known as organophosphorus-based flame retardants are well known. Among such organic phosphorus-based flame retardants, preferred are phosphoric acid esters and condensed phosphate esters, phosphorus-containing (meth) acrylates, phenolic hydroxyl group-containing phosphorus-containing compounds, and cyclic phosphorous compounds. A nitrogen compound, a phosphorus-nitrogen ring oligomer, a phosphonic acid metal salt, or a compound represented by the following general formula (I).

(wherein R ⁵ , R ⁶ and R ⁷ each independently represent a substituent other than a halogen atom.)

In the above general formula (I), R ⁵ and R ⁶ are preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ⁷ is a group having 1 to 4 carbon atoms which may be substituted by a hydrogen atom or a cyano group. The alkyl group, 2,5-dihydroxyphenyl group or 3,5-di-t-butyl-4-hydroxyphenyl group is preferably, but not limited thereto.

Commercially available products of the phosphorus-containing compound represented by the above general formula (I) include HCA, SANKO-220, M-ESTER, and HCA-HQ (all of which are trade names of Sanko Corporation).

The (meth) acrylate containing a phosphorus element is preferably a compound having a phosphorus element and having a plurality of (meth) acrylonitrile groups in the molecule, and specifically, R ⁵ in the above general formula (I) A compound wherein R ⁶ is a hydrogen atom and R ⁷ is a (meth) acrylate derivative. In general, it is possible to carry out a Mac addition reaction of 9,10-dihydro-9-oxa-10-phosphinophene-10-oxide with a well-known polyfunctional (meth) acrylate monomer. To synthesize.

Examples of the (meth) acrylate monomer include diacrylates of ethylene glycol such as ethylene diol, methoxytetraethylene diol, polyethylene diol, and propylene glycol; hexanediol and trishydroxyl a polyvalent acrylate such as propane, pentaerythritol, dipentaerythritol or hydroxyethyl isocyanate or a polyvalent acrylate such as an oxyethylene adduct, a propylene oxide adduct or a caprolactone adduct a phenoxy acrylate, a bisphenol A diacrylate, and a polyvalent acrylate such as an oxyethylene adduct or a propylene oxide adduct of the above phenol; and a urethane of the above polyalcohol Acrylates, glycerol dioxypropylene ether, glycerol triepoxypropyl ether, trimethylolpropane triepoxy a polyvalent acrylate of a glycidyl ether such as propyl ether or triglycidyl isocyanurate; and at least one of melamine acrylate and each methyl acrylate corresponding to the above acrylate Wait.

A phosphorus-containing compound having a phenolic hydroxyl group has high hydrophobicity and heat resistance, and has no deterioration in electrical properties due to hydrolysis, and has high solder heat resistance. Further, as an appropriate combination, when an epoxy resin is used in the thermosetting resin, it reacts with the epoxy group and is absorbed by the system, so that there is an advantage that it does not overflow after curing. Among the phosphorus-containing compounds having a phenolic hydroxyl group, preferred examples of the above formula (I) include that R ⁷ is a phenyl group substituted with a hydroxyl group. As a commercial item, HCA-HQ manufactured by Sanko Co., Ltd., etc.

The phosphorus-containing compound of the oligomer or polymer has less reduction in the folding property due to the influence of the alkyl chain, and because of the large molecular weight, it is possible to obtain the advantage of no overflow after hardening. As a commercial item, M-Ester-HP manufactured by Sanko Co., Ltd., and Byron 337 containing phosphorus manufactured by Toyobo Co., Ltd. are available.

As a phosphorus-nitrogen ring oligomer, a phenoxyphosphazene ring compound is effective, although a substituted or unsubstituted phenoxyphosphazene ring oligomer or a trimer, a tetramer, a pentamer ring Any one of them is liquid or solid powder, but any one can be used as appropriate. As a commercial item, FP-100, FP-300, FP-390, etc. manufactured by Fushimi Pharmaceutical Co., Ltd. are available. Among them, a phenoxyphosphazene ring oligomer substituted with a polar group such as an alkyl group or a hydroxyl group or a cyano group has high solubility in a resin containing a carboxyl group, and there is no problem such as recrystallization even when added in a large amount. Therefore, it is better.

Further, the other phosphorus-nitrogen ring oligomer is obtained by reacting at least one of a phosphorus-containing dicarboxylic acid represented by the following general formula (II) and an acid anhydride thereof with an acrylate compound, and contains 1 in the molecule. More than one (meth) acrylate compound.

The hydrocarbon group having 1 to 6 carbon atoms represented by R ⁸ and R ⁹ in the above general formula (II) may, for example, be an alkyl group having 1 to 6 carbon atoms or an alkenyl group having 1 to 6 carbon atoms or a ring. Alkyl, phenyl. Examples of the alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a second butyl group, a tert-butyl group, an isobutyl group, a pentyl group, and an isopentyl group. And a third pentyl group, a hexyl group, etc., as an alkenyl group having 1 to 6 carbon atoms, examples thereof include a vinyl group, a propenyl group, a 3-butenyl group, an isobutenyl group, a 4-pentenyl group, a 5-hexenyl group, and the like. . The hydrocarbon group having 1 to 6 carbon atoms may be either branched or substituted.

Examples of the above-mentioned dicarboxylic acid containing a phosphorus element or an anhydride thereof include a reaction of reacting 9,10-dihydro-9-oxa-10-phosphinophene phenanthrene-10-oxide with itaconic acid. And its anhydride and the like.

As the acrylate compound, an acrylate compound having a functional group reactive with a carboxyl group or a carboxylic anhydride of the above dicarboxylic acid or its anhydride is preferred. The acrylate residue can be added by a related reaction. The acrylate compound may be a monofunctional acrylate having one (meth) acrylate group in the molecule, or a polyfunctional acrylate having two or more (meth) acrylate groups in the molecule. Examples of the functional group include an epoxy group, a hydroxyl group, an amine group and the like. Examples of the acrylate compound having an epoxy group include a glycidyl (meth) acrylate, 2-methyl-2,3-epoxypropyl (meth) acrylate, and the like. Examples of the acrylate compound having a hydroxyl group include 2-hydroxyethyl acrylate and 2-hydroxypropyl acrylate. Examples of the acrylate compound having an amine group include diethylamine ethyl acrylate and the like. Among the above functional groups, an epoxy group and a hydroxyl group are more preferred.

A conventionally known reaction method can be used in the reaction method in which the above functional group is added.

Examples of the above-mentioned phosphorus-nitrogen ring oligomer include one or two functional groups obtained by reacting a phosphorus-containing dicarboxylic acid of the general formula (II) synthesized in the above examples with methyl propyl acrylate. A phosphorus-nitrogen ring oligomer, or a dicarboxylic acid containing a phosphorus element of the general formula (II), a hydroxy (meth) acrylate, and a bifunctional phosphorus-nitrogen ring oligomer obtained by reacting with diethanol.

The amount of the acrylate compound to be added is not particularly limited, and the phosphorus concentration of the phosphorous-nitrogen ring oligomer is adjusted to 2 to the dicarboxylic acid or an acid anhydride containing the phosphorus element represented by the above formula (II). 7% Within the scope, it is preferred as the acrylate compound.

By using the dicarboxylic acid containing a phosphorus element represented by the above general formula (II) or an anhydride thereof, a phosphorous-nitrogen ring oligomer having acrylated at both terminals can be easily obtained. By using the terminally acrylated phosphorous-nitrogen ring oligomer thus obtained, a photosensitive resin composition can be obtained, which is excellent in flexibility and low flexibility, and does not occur during hot pressing. A flame retardant film that overflows.

The above-mentioned phosphorus-nitrogen ring oligomer is a bifunctional phosphorus-containing acrylate, and is preferable from the viewpoint of flexibility and low flexibility. When the phosphorus-nitrogen ring oligomer is bifunctional, the heat resistance is improved, and the decrease in flexibility can be suppressed.

Further, the above-mentioned phosphorus-nitrogen ring oligomer may be used alone or in combination of two or more.

Further, by using the metal phosphonic acid salt, the softness of the cured film can be prevented from being deteriorated and the flame retardancy can be improved. By using such a phosphonic acid metal salt excellent in heat resistance, it is possible to suppress the overflow of the flame retardant under heat stress at the time of mounting.

Specific examples of the phosphonic acid constituting the phosphonic acid metal salt include phosphonic acid, dimethylphosphonic acid, ethylmethylphosphonic acid, diethylphosphonic acid, methyl-n-propylphosphonic acid, methane II. (Methylphosphonic acid), Benzene-1,4-(dimethylphosphonic acid), phenylphosphonic acid, phenylphosphonic acid, diphenylphosphonic acid, and mixtures thereof.

Examples of the metal component constituting the phosphonate include calcium, magnesium, aluminum, zinc, barium, manganese, sodium, and potassium. Preferred are calcium, magnesium, aluminum and zinc.

As a commercial product of a phosphonic acid metal salt, there is a Clariant The company's EXOLIT OP 930, EXOLIT OP 935 and so on.

The phosphorus-containing compound may be used alone or in combination of two or more. The blending amount of the compound containing phosphorus is 5 to 150 parts by mass, preferably 10 to 100 parts by mass, per 100 parts by mass of the resin containing the carboxyl group (A). When it is 150 parts by mass or less, the folding properties and the like of the obtained cured film become good.

As the metal hydroxide, those which can exhibit flame retardancy by heat decomposition such as aluminum hydroxide, magnesium hydroxide, calcium hydroxide, barium hydroxide or barium hydroxide can be used. Among them, aluminum hydroxide or magnesium hydroxide can be used particularly suitably.

The aluminum hydroxide may be a surface untreated, or a surface treatment may be carried out using a decane coupling agent having a vinyl group or an epoxy group at the terminal, octadecanoic acid, oleic acid, a phosphate ester or the like. As a commercial product of aluminum hydroxide, Higilite H-42, H-42M, H-42S, H-42T, H-42ST-V, H-42ST-E, H-42I, manufactured by Showa Denko Co., Ltd. H-43, H-43M, H-43S, B1403, B1403ST, B1403T, etc., manufactured by Nippon Light Metal Co., Ltd.

As the magnesium hydroxide, it may be a natural product or a synthetic material, or may be a surface untreated, or a decane coupling agent having a vinyl group or an epoxy group at the terminal, octadecanoic acid or oil. A surface treatment agent such as an acid or a phosphate ester. Commercially available products of magnesium hydroxide include KISUMA 5A, KISUMA 5B, KISUMA 5E, KISUMA 5J, KISUMA 5P, KISUMA 5L, Magnifin H5, Magnifin H7, Magnifin H10 manufactured by Albemarle Co., Ltd., and the like.

The blending amount of the inorganic filler imparting flame retardancy such as aluminum hydroxide or magnesium hydroxide is preferably 500 parts by mass or less, more preferably 0.1 to 300 mass, per 100 parts by mass of the above (A) carboxyl group-containing resin. It is particularly preferably 0.1 to 150 parts by mass. When the blending amount of the filler is 500 parts by mass or less, the viscosity of the photosensitive resin composition is not excessively high, the printability is good, and the cured product is hard to be brittle.

The average particle diameter (d50) of the inorganic filler imparting flame retardancy is preferably 30 μm or less, and more preferably 15 μm or less. By setting the average particle diameter to 30 μm or less, it is possible to make the rubbing trace more difficult to occur. The lower limit of the average particle diameter (d50) is, for example, 0.05 μm or more. The average particle diameter (d50) can be measured by a laser diffraction/scattering method.

(thermosetting component)

It is preferred to incorporate a thermosetting component into the photosensitive resin composition of the present invention. By adding a thermosetting component, heat resistance can be expected to increase. As the thermosetting component, any of the conventional ones can be used. For example, an amine resin such as a melamine resin, a benzoguanamine resin, a melamine derivative or a benzoguanamine derivative, an isocyanate compound, a blocked isocyanate compound, a cyclic carbonate compound, a polyfunctional epoxy compound, or a polyfunctional epoxy can be used. A conventional thermosetting component such as a propane compound, an epoxy sulfide resin, a bismaleimide, or a carbodiimide resin. Particularly preferred is a thermosetting component having a plurality of cyclic ether groups or cyclic ethyl sulfide groups (hereinafter abbreviated as cyclic (thio)ethyl ether groups) in the molecule. The thermosetting component can be used singly or in combination of two or more.

The thermosetting component having a plurality of cyclic (thio)ethyl ether groups in the above molecule is a compound having a cyclic (thio)ethyl ether group having a plurality of 3, 4 or 5 membered rings in the molecule, for example, having a complex number in the molecule a compound having an epoxy group, that is, a polyfunctional epoxy compound, a compound having a plurality of propylene oxide groups in the molecule, that is, a polyfunctional propylene oxide compound, a compound having a plurality of ethane sulfide groups in the molecule, that is, Epoxy sulfide resin, etc.

As the polyfunctional epoxy compound, there are epoxidized vegetable oil; bisphenol A type epoxy resin; hydroquinone type epoxy resin; bisphenol type epoxy resin; ethyl sulfide type epoxy resin; brominated epoxy resin; Phenolic epoxy resin; bisphenol novolac epoxy resin; bisphenol F epoxy resin; hydrogenated bisphenol A epoxy resin; epoxy propyl amine epoxy resin; Epoxy epoxy resin; trishydroxyphenylmethane epoxy resin; bisxylenol or diphenol epoxy resin or a mixture thereof; bisphenol S epoxy resin; bisphenol A phenolic epoxy Resin; tetraethylbenzene type epoxy resin; complex element ring type epoxy resin; digoxypropyl phthalate resin; tetraglycidyl xylene decyl ethane resin; epoxy resin containing naphthyl group; Epoxy resin having a cyclopentadiene skeleton; epoxy methacrylate copolymerized epoxy resin; copolymerized epoxy resin of cyclohexylmaleimide and epoxypropyl methacrylate; epoxy A modified polybutadiene rubber derivative; a CTBN modified epoxy resin or the like, but is not limited thereto. These epoxy resins can be used alone or in combination of two or more. Among these, especially phenolic epoxy resin, bisphenol epoxy resin, bisxylenol epoxy resin, bisphenol epoxy resin, bisphenol novolac epoxy resin, naphthalene epoxy resin or Mixtures of these are preferred.

As the polyfunctional propylene oxide compound, for example, bis[(3-methyl-3-epoxypropane methoxy)methyl]ether, bis[(3-ethyl-3-epoxypropane methoxy) Methyl]ether, 1,4-bis[(3-methyl-3-epoxypropanemethoxy)methyl]benzene, 1,4-bis[(3-ethyl-3-epoxypropane methoxy) Methyl]benzene, (3-methyl-3-epoxypropane) methacrylate, (3-ethyl-3-epoxypropane) methacrylate, (3-methyl-3-ring Oxypropane) methyl methacrylate, (3-ethyl-3-epoxypropane) methyl methacrylate or polyfunctional propylene oxides such as oligomers or copolymers thereof Examples of ethers of propylene propanol and phenolic resins, poly(p-hydroxystyrene), cation-based bisphenols, phenolic cyclic polymers, aromatic cups or resins having hydroxyl groups such as hemi-oxyalkylene Compounds, etc. Further, a copolymer of an unsaturated monomer having a propylene oxide ring and an alkyl (meth) acrylate or the like is also mentioned.

Examples of the compound having a plurality of cyclic ethyl sulfide groups in the molecule include a bisphenol A type epoxy sulfide resin and the like. Further, an epoxy sulfide resin obtained by substituting an oxygen atom of an epoxy group of a novolac type epoxy resin into a sulfur atom by the same synthesis method can also be used. The blending amount of the thermosetting component having a plurality of cyclic (thio)ethyl ether groups in the molecule is preferably from 0.6 to 2.5 equivalents per equivalent of the carboxyl group of the (A) carboxyl group-containing resin. When the blending amount is 0.6 equivalent or more, it is difficult to leave a carboxyl group on the cured product, and heat resistance, alkali resistance, electrical insulation, and the like are preferably good. On the other hand, when it is 2.5 equivalent or less, the low molecular weight cyclic (thio)ethyl ether group is less likely to remain on the dried coating film, and the strength of the coating film is good. More preferably, it is 0.8 to 2.0 equivalents.

Examples of the amine-based resin such as a melamine derivative or a benzoguanamine derivative include a methylol melamine compound and a hydroxymethyl benzoguanamine compound. , hydroxymethylethyl urea compound, hydroxymethyl urea compound and the like.

As the isocyanate compound, a polyisocyanate compound can be blended. Examples of the polyisocyanate compound include 4,4'-diphenylmethane diisocyanate, 2,4-diisocyanate toluene, 2,6-diisocyanate toluene, naphthalene-1,5-diisocyanate, and o. -Aromatic polyisocyanate such as phenyldimethyl diisocyanate, m- benzene dimethyl diisocyanate and 2,4-methylphenyl dimer; tetramethene diisocyanate, hexamethylene diisocyanate, methylene Aliphatic polyisocyanates such as diisocyanate, trimethylhexamethylene diisocyanate, 4,4-methanebis(cyclohexyl isocyanate) and isophorone diisocyanate; alicyclic polyisocyanates such as biscycloheptane triisocyanate And an adduct of an isocyanate compound, a biuret body, an isocyanurate body, etc. which were mentioned previously.

As the blocked isocyanate compound, an addition reaction product of an isocyanate compound and an isocyanate block agent can be used. As the isocyanate compound which can react with an isocyanate block agent, the polyisocyanate compound mentioned above, etc. are mentioned, for example. Examples of the isocyanate block agent include a phenol-based block agent; an internal guanamine-based block agent; a reactive methene-based block agent; an alcohol-based block agent; an oxime-based block agent; and a thiol-based block agent; Amidoxime blocker; a sulfonium blocker; an amine blocker; an imidazole blocker; an imide blocker, etc.

The blending amount of the polyisocyanate compound or the blocked isocyanate compound is preferably from 1 to 100 parts by mass per 100 parts by mass of the (A) carboxyl group-containing resin. When the blending amount is 1 part by mass or more, a sufficient toughness of the coating film can be obtained. On the other hand, when it is 100 mass or less, save it. Good stability. More preferably, it is 2 to 70 parts by mass.

(other photopolymerizable monomers)

The photosensitive resin composition of the present invention may contain (B) urethane (meth) acrylate and a phosphorus-containing (meth) acrylate which can be used as a flame retardant, and may contain other photopolymerizable properties. monomer. The photopolymerizable monomer is a compound having one or more ethylenically unsaturated groups in the molecule, and is photohardened by irradiation with an active energy ray, and then the above-mentioned (A) carboxyl group-containing resin is insolubilized or helps to dissolve in an aqueous alkali solution. By.

As a compound used as another photopolymerizable monomer, any of the conventional ones can be used. For example, conventionally used polyester (meth) acrylate, polyether (meth) acrylate, carbonate (meth) acrylate, epoxy (meth) acrylate can be used, specifically, 2 a hydroxyalkyl acrylate such as hydroxyethyl acrylate or 2-hydroxypropyl acrylate; a diacrylate of ethylene glycol such as ethylene glycol, methoxytetraethylene glycol, polyethylene glycol or propylene glycol; N,N-dimethyl methacrylate, N-methylol acrylamide, N,N-dimethylaminopropyl acrylamide, etc.; N,N-dimethylamino Aminoalkyl acrylate such as ethyl acrylate or N,N-dimethylaminopropyl acrylate; hexanediol, trimethylolpropane, pentaerythritol, dipentaerythritol, cis-hydroxyethyl isocyanate, etc. a polyvalent acrylate such as a polyvalent alcohol or such an oxyethylene adduct, a propylene oxide adduct or an ε-caprolactone adduct; a phenoxy acrylate, a bisphenol A diacrylate, and Multivalent valence of such phenolic oxyethylene adducts or propylene oxide adducts Acrylates; glycidyl ethers such as glycerol dipropylene oxide, glycerol triepoxypropyl ether, trimethylolpropane triepoxypropyl ether, triglycidyl isocyanurate The polyvalent acrylates; not limited to the above, there are also acrylates which are directly acrylated with a polyol such as a polyether polyol, a polycarbonate diol, a hydroxyl terminated polybutadiene or a polyester polyol. And each methyl acrylate or the like corresponding to melamine acrylate and/or the above acrylate. The other photopolymerizable monomers can be used singly or in combination of two or more.

The total amount of the photopolymerizable monomer containing the above (B) urethane (meth) acrylate and a phosphorus-containing (meth) acrylate which can be used as a flame retardant is a carboxyl group with respect to the above (A) The resin is 100 parts by mass, preferably 10 to 250 parts by mass, more preferably 10 to 200 parts by mass. When the amount is 10 parts by mass or more, the photocurability is good, and the pattern is easily formed by alkali development after activation of the energy ray. On the other hand, when it is 250 parts by mass or less, the solubility in an aqueous alkali solution is good, and the decrease in resolution can be suppressed.

(Antioxidants)

After a large number of polymer materials are once oxidized, continuous oxidation deterioration occurs and the function of the polymer material is lowered. Therefore, in order to prevent oxidation of the photosensitive resin composition of the present invention, (1) The radical replenishing agent which invalidates the generated radicals and/or (2) decomposes the generated peroxide into a harmless substance, and does not generate an antioxidant such as a new radical peroxide decomposing agent.

As an antioxidant having a function as a radical supplement, specific examples of the compound include hydroquinone, 4-tert-butylcatechol, 2-t-butylhydroquinone, hydroquinone monomethyl ether, and 2. 6-di-t-butyl-p-cresol, 2,2-methylenebis-(4-methyl-6-t-butylphenol), 1,1,3-parade (2-methyl- 4-hydroxy-5-t-butylphenyl)butane, 1,3,5-trimethyl-2,4,6-paran (3,5-di-t-butyl-4-hydroxybenzyl Benzene, 1,3,5-gin (3',5' di-t-butyl-4-hydroxybenzyl)-S-triazabenzene-2,4,6-(1H,3H,5H) a phenolic compound such as a triketone, an anthraquinone compound such as methylhydrazine or benzoquinone, or a bis(2,2,6,6-tetramethyl-4-piperidyl)-sebacate or a thiodiphenylamine. An amine compound or the like.

Free radical supplements are also commercially available, such as ADKSTAB AO-30, ADKSTAB AO-330, ADKSTAB AO-20, ADKSTAB LA-77, ADKSTAB LA-57, ADKSTAB LA-67, ADKSTAB LA-68, ADKSTAB LA-87 (above, manufactured by ADEKA), IRGANOX1010, IRGANOX1035, IRGANOX1076, IRGANOX1135, TINUVIN 111FDL, TINUVIN 123, TINUVIN 144, TINUVIN 152, TINUVIN 292, TINUVIN 5100 (above, BASF Japan, trade name) Wait. Examples of the specific antioxidant include a phosphorus compound such as triphenyl phosphite, pentaerythritol tetralauryl thiopropionate, and dilauryl thiodipropionic acid. A sulfur-based compound such as an ester or a distearyl 3,3'-thiodipropionate.

The peroxide decomposing agent may be commercially available, for example, ADKSTAB TPP (trade name, manufactured by Adeka Co., Ltd.), Mark AO-412S (trade name, manufactured by Adeka Co., Ltd.), SUMIIZER TPS (Sumitomo Chemical Co., Ltd.) Learn company system, trade name) and so on.

The above-mentioned antioxidants can be used singly or in combination of two or more.

(Organic solvents)

The photosensitive resin composition of the present invention can be used for the preparation of a synthesis or composition of (A) a carboxyl group-containing resin, or for a substrate or an organic solvent for viscosity adjustment applied to a carrier film. Examples of such an organic solvent include ketones, aromatic hydrocarbons, glycol ethers, glycol ether acetates, esters, alcohols, aliphatic hydrocarbons, petroleum solvents, and the like. More specifically, there are ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; celecoxime, methyl acesulfame, butyl quercetin, carbitol, Glycol ethers such as methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, triethylene glycol monoethyl ether; Esters such as ester, butyl acetate, dipropylene glycol methyl ether acetate, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol butyl ether acetate; ethanol, propanol, ethylene Alcohols such as alcohols and propylene glycol; aliphatic hydrocarbons such as octane and decane; petroleum solvents such as petroleum ether, petroleum brain, hydrogenated petroleum brain, and solvent petroleum brain. These organic solvents can be used singly or in combination of two or more.

(other optional ingredients)

The photosensitive resin composition of the present invention may further contain a whitening additive which reduces the b ^* value in the L ^* a ^* b ^* color system of the cured product of the composition by heating. Here, the whitening additive means a person who can increase the whiteness of the cured product of the composition so that it does not appear to be discolored.

This, in case the specification, by heating the cured composition to reduce the b ^* value means that the initial heating of the composition was cured, it will reduce the b ^* values, and does not include the second and subsequent heating times. Further, the heating temperature at this time means a temperature at which the composition is substantially solder-mounted, specifically, 200 ° C or higher, for example, 220 to 370 ° C. A typical solder reflow step is performed only once at about 260 °C. In the case of an additive for whitening, heating at a temperature of about 150 ° C of the curing temperature of the composition does not cause a decrease in the b ^* value.

As the whitening additive, those having a benzoxazole-based skeleton can be suitably used, and one or more of them have the following formula (I).

(wherein, R ¹ and R ² each independently represent a compound having a structure represented by a linear or branched alkyl group having 1 to 12 carbon atoms) is preferred. In particular, R ¹ and R ² are each preferably an alkyl group having 4 to 8 carbon atoms, and more preferably a butyl group or an octyl group. Specifically, the following formula (I-1) can be suitably used. )~(I-3)

(4,4'-[5-t-butyl-2-benzoxazolyl-4'-(5-t-octyl-2-benzoxazolyl)]stilbene)

(4,4'-bis-[5-t-octyl-2-benzoxazolyl]stilbene)

(4,4'-bis-[5-t-butyl-2-benzoxazolyl]stilbene)

Any one of the compounds shown, or a mixture of two or more, especially three. Further, as an additive for whitening, a decomposition temperature of 400 ° C or more is suitable. Here, the reason why the decomposition temperature of the whitening additive is set to 400 ° C or higher is to prevent the preparation of the additive at 350 ° C in the remelting step, and the additive due to the thermal load is self-contained. break down. The upper limit of the decomposition temperature is not particularly limited, but is, for example, 400 ° C to 600 ° C.

The blending amount of the whitening additive is preferably 0.01 to 60 parts by mass, more preferably 0.1 to 40 parts by mass, per 100 parts by mass of the (A) carboxyl group-containing resin.

Further, the photosensitive resin composition of the present invention may further comprise a photoexcitable inorganic filler to which a surface treatment is applied. The photo-excitable inorganic filler applied to the surface treatment means that the inorganic component is applied to the photo-excitable inorganic filler Or surface treatment of acidic liquids. By using the photoexcitable inorganic filler to which the surface treatment is applied, and further satisfying the conditions relating to the pH value described later, it is possible to achieve high reflectance in the cured coating film. The application of the surface treatment to the photoexcitable inorganic filler is because the surface of the photoexcitable inorganic filler forms an insoluble or poorly soluble reaction product by the surface treatment, and the water resistance of the surface thereof is violent. The ground lift can also achieve the effect of maintaining high reflectance for a long period of time in the presence of water.

Examples of the photoexcitable inorganic filler include aluminate bismuth, zinc sulfide, and the like, and in particular, aluminate strontium can be suitably used. These photoexcitable inorganic fillers may be used alone or in combination of two or more. Further, examples of the inorganic component used for the surface treatment include ceria (glass), alumina, and zirconia. As a method of surface treatment using an inorganic component, a well-known method can be used, and it is not specifically limited.

Further, as the acidic liquid, one selected from the group consisting of nitric acid, hydrochloric acid, carbonic acid, sulfuric acid, sulfurous acid, citric acid, boric acid, phosphoric acid, phosphorous acid, polyphosphoric acid, sodium monophosphate, sodium hexametaphosphate, acetic acid, butyric acid, and propionic acid can be used. , octanoic acid, lauric acid, octadecanoic acid, acrylic acid, methacrylic acid, oxalic acid, succinic acid, citric acid, malic acid, tartaric acid, adipic acid, azelaic acid, sebacic acid, phthalic acid, salicylic acid Acid, benzoic acid, gallic acid, phenol, naphthoic acid, toluenesulfonic acid, benzenesulfonic acid, metaphosphoric acid, taurine, ascorbic acid, stanol acid, phosphonic acid, crotonic acid, maleic acid, lactic acid or the like An acid salt such as a potassium salt, a sodium salt, an ammonium salt, or an acid anhydride, or an acid compound such as an acid anhydride, wherein phosphoric acid such as phosphoric acid, phosphorous acid, polyphosphoric acid, or sodium phosphate, and the like are used. Salt structure The phosphate compound and sulfuric acid are preferred, and the phosphate compound is particularly preferred. The inorganic component and the acidic liquid can be used alone or in combination of two or more.

Here, the surface treatment of the acidic liquid can be carried out using the above acidic liquid at a pH of 3 or less, for example, a method of immersing a photo-excitable inorganic filler in an aqueous solution containing an acidic liquid, and photoexcitability. The inorganic filler sprays a method containing an aqueous solution of an acidic liquid to bring the surface of the photoexcitable inorganic filler into contact with an acidic liquid in a high humidity environment. Among these methods, a method of immersing a photo-excitable inorganic filler in an aqueous solution containing an acidic liquid is preferable from the viewpoint of easy operation and efficient reaction.

Specifically, first, the acidic liquid is prepared in an amount of about 1 to 1000 times by mass, preferably about 2 to 100 times by mass, more preferably about 3 to 10 times by mass, based on the photoexcitable inorganic filler. The solution is dissolved to a concentration of about 0.01 to 30% by mass, preferably about 0.5 to 10% by mass. At this time, in order to adjust the solubility of the acidic liquid, a part of the water can be replaced with methanol, ethanol, acetone, dioxane, dimethylformamide (DMF), dimethyl hydrazine (DMSO), or the like. A water-soluble organic solvent. In this case, the amount of the organic solvent to be used is not particularly limited as long as it does not inhibit the reaction between the metal oxide of the photoexcitable inorganic filler and the acidic liquid, but it is usually provided in a smaller capacity than the water used. the amount. Further, in the aqueous solution, a surfactant may be added in order to enhance the dispersibility of the photoexcitable inorganic filler. The kind and amount of the surfactant, etc. can be appropriately determined depending on the kind and amount of the photo-excitable inorganic filler to be used. Adjustment.

Next, a photo-excitable inorganic filler is added to an aqueous solution containing an acidic liquid, and the mixture is uniformly dispersed by stirring to cause an acidic liquid to react with the metal oxide of the photo-excitable inorganic filler. The treatment temperature at this time is not particularly limited, but the liquid temperature can be usually set to about 20 ° C or higher, preferably from 50 ° C to less than the boiling point, and the treatment time can be set to 0.5 to 120 minutes, preferably 10~60 minutes.

After the surface treatment of the above acidic liquid, at least one basic compound selected from the group consisting of an alkali or a base producing compound can be used for the alkali treatment. The alkali treatment is carried out at a pH of 4 to 9, preferably at a pH of 4 to 7. By the alkali treatment, the durability of the water-repellent inorganic filler obtained by the surface treatment using the above-mentioned acidic liquid is improved, and the water resistance can be maintained even when used at a high temperature for a long period of time. This is considered to be that the reaction product formed on the surface of the photoexcitable inorganic filler is denatured to be more strengthened by alkali treatment. As the base to be used for the alkali treatment, sodium hydroxide, lithium hydroxide, calcium hydroxide, potassium hydroxide, barium hydroxide, ammonia or the like is used, but sodium hydroxide is preferably used. Further, as the base generating compound, sodium second sodium phosphate, sodium third phosphate, sodium hexametaphosphate, sodium acetate, cesium hydride or the like is used, but it is more appropriate to use sodium third phosphate. Further, an organic basic compound such as monoethanolamine, triethanolamine, hydrazine, stearylamine or acridine can be used.

The means for the alkali treatment is not particularly limited, and can be carried out, for example, as follows. That is, after the treatment of the acidic liquid described above, the supernatant liquid can be removed, and an appropriate amount of water can be newly added. Next, stir with a blender, etc. The above basic compound was slowly added while mixing, and the pH was adjusted to 4 to 9. The treatment temperature at this time is not particularly limited, but the liquid temperature is usually set to about 20 ° C or higher, and more suitably from 50 ° C to less than the boiling point. The processing time is usually set at 0.5 to 120 minutes, more suitably 10 to 60 minutes.

After the alkali treatment, the supernatant is removed, filtered and washed with water, and then sufficiently dried to obtain a photoexcitable inorganic filler which is subjected to a surface treatment. The drying conditions at this time are not particularly limited, but they are usually dried at a temperature of 20 ° C or higher for 2 hours or longer. The surface-treated photoexcitable inorganic filler can be obtained in a powdery state by sieving if necessary. The photo-excitable inorganic filler to be surface-treated as described above has a solubility of less than 1 g with respect to 100 g of water at 40 ° C, and since it has heat resistance, it can maintain very good water resistance for a long period of time.

In addition, 10 g of the photo-excitable inorganic filler was added to 50 g of acetone as a photo-excitable inorganic filler to which the surface treatment was applied, and the insoluble component was taken out once. Then, the insoluble component taken out was added to 50 g of chloroform, and the second insoluble matter was taken out. After the component, the second insoluble component to be taken out is further added to 10 g of pure water, and the pH of the liquid obtained after stirring at 30 ° C for one week is preferably from 6 to 12, so that a high reflectance is obtained.

The blending amount of the photo-excitable inorganic filler is, for example, 0.1 to 500 parts by mass based on 100 parts by mass of the (A) carboxyl resin.

In the photosensitive resin composition of the present invention, a thermosetting catalyst, a urethane catalyst, or an epoxy can be further blended as necessary. Hardener thermoplastic resin, block copolymer, filler, binder polymer, synthetic rubber, adhesion promoter, antioxidant, UV absorber, thermal polymerization inhibitor, etc. Thus, it is possible to use what is known in the field of electronic materials. Further, in the photosensitive resin composition of the present invention, a known conventional tackifier such as fine powder of ceria, hydrotalcite, organic bentonite or kaolinite, an anthracene oxygen system, a fluorine system or a polymer system can be blended. A conventionally used additive such as an antifoaming agent and/or a leveling agent, a decane coupling agent such as an imidazole system, a thiazole system or a triazole system, or a rust removing agent.

The photosensitive resin composition of the present invention is useful for forming a protective layer of a circuit pattern of a printed wiring board, and is particularly useful for forming a permanent insulating film. Among them, it is useful as a material required to form the outermost layer portion, such as a solder resist or a backing film. In particular, there is a material for use as a solder resist or a backing film for a flexible printed wiring board having a light-emitting element such as an LED. The flexible printed wiring board having the solder resist formed by the photosensitive resin composition of the present invention can be suitably used for a back sheet such as LED lighting. Further, the photosensitive resin composition of the present invention can be used not only in a flexible printed wiring board but also in a rigid printed wiring board. Further, the photosensitive resin composition of the present invention can also be used in the formation of a solder dam.

The photosensitive resin composition of the present invention can be in the form of a dry film comprising a carrier film (support) and a layer composed of the photosensitive resin composition formed on the carrier film. In the case of dry film formation, the photosensitive resin composition of the present invention can be diluted with the above organic solvent and adjusted to an appropriate viscosity, and a spot coater, a sheet coater, a blade coater, a rod coater, and a squeeze. Press coater, reverse coater, transfer roller coater, gravure A coater, a spray coater, or the like is applied to the carrier film in a uniform thickness, and is usually dried at a temperature of 50 to 130 ° C for 1 to 30 minutes to obtain a film. The coating film thickness is not particularly limited, and generally, the film thickness after drying is appropriately selected in the range of 1 to 150 μm, preferably 10 to 60 μm.

As the carrier film, a plastic film, a polyester film such as polyethylene terephthalate, a polyimide film, a polyimide film, a polypropylene film, a polystyrene film, or the like is used. The plastic film is preferred. The thickness of the carrier film is not particularly limited, but is generally selected in the range of 10 to 150 μm.

After forming the photosensitive resin composition of the present invention on the carrier film, it is preferable to laminate the cover film which can be peeled off on the surface of the film for the purpose of preventing dust from adhering to the surface of the film. As the cover film which can be peeled off, for example, a polyethylene film, a polytetrafluoroethylene film, a polypropylene film, a surface-treated paper, or the like can be used, and when the cover film is peeled off, the adhesion force between the film and the cover film is higher than that of the film and the carrier film. Then the force is small.

The photosensitive resin composition of the present invention is adjusted to a viscosity suitable for the coating method by the above-mentioned organic solvent, for example, by a dip coating method, a flow coating method, a roll coating method, a rod coating method, or a screen printing method on a substrate. By coating by a method such as a curtain coating method, the organic solvent contained in the composition is volatilized and dried (temporarily dried) at a temperature of about 60 to 100 ° C, whereby a coating film which does not peel off can be formed. In addition, when the composition is applied to a carrier film and dried to be a dry film which is rewound as a film, the photosensitive resin composition layer is brought into contact with the substrate after bonding to the substrate by a bonding machine or the like. ,borrow A resin insulating layer can be formed by peeling off the carrier film.

Examples of the substrate include a printed wiring board or a flexible printed wiring board in which a circuit is formed in advance, and phenol paper, epoxy paper, glass cloth epoxy, glass polyimide, glass, and the like. Cloth/non-woven epoxy, glass cloth/paper epoxy, synthetic fiber epoxy, fluorine. Polyethylene. Polyphenylene ether, polyoxymethylene. Copper-clad laminates of all grades (FR-4, etc.), other polyimide films, PET films, glass substrates, ceramic substrates, and wafer plates of materials such as copper-clad laminates for high-frequency circuits such as cyanate esters. Wait.

The volatilization drying performed after applying the photosensitive resin composition of the present invention can be performed by using a hot air circulation type drying furnace, an IR furnace, a heating plate, a convection oven, or the like (using a heat source having a vapor heating method to heat the inside of the dryer) This is done by a method of contacting the flow and a method of blowing the nozzle toward the support.

When the photosensitive resin composition of the present invention contains a thermosetting component, it can be thermally cured by heating to a temperature of, for example, about 140 to 180 ° C to bond a carboxyl group and a thermosetting component in the resin containing the carboxyl group of the above (A). The reaction forms a cured coating film having various properties such as heat resistance, chemical resistance, moisture absorption resistance, adhesion, and electrical properties.

The coating film obtained by applying the photosensitive resin composition of the present invention and volatilizing the drying solvent is exposed (irradiation by an active energy ray), and the exposed portion (the portion irradiated with the active energy ray) is hardened. And, by contact (or non-contact), by forming a pattern of the reticle, and selectively exposing by active energy ray or direct exposure by a laser direct exposure machine After the exposure, the unexposed portion is developed with a dilute aqueous alkali solution (for example, 0.3 to 3 mass% aqueous sodium carbonate solution) to form a photoresist pattern.

The exposure machine used for the activation energy ray irradiation may be a device that is equipped with a high-pressure mercury lamp, an ultra-high pressure mercury lamp, a metal halide lamp, a mercury short-arc lamp, and the like, and irradiates ultraviolet rays in the range of 350 to 450 nm. It is also possible to further use a direct drawing device (for example, a laser direct imaging device that directly draws an image by laser data from a computer). As the laser light source of the direct drawing machine, as long as it uses laser light having a maximum wavelength in the range of 350 to 410 nm, it can be either a gas laser or a solid laser. The amount of exposure for image formation varies depending on the film thickness, etc., but it can be generally set in the range of 10 to 100 mJ/cm ² , preferably 20 to 800 mJ/cm ² .

As the development method, a immersion method, a water spray method, a spray method, a brushing method, or the like can be used as the developing liquid, and potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium citrate, or the like can be used. An aqueous solution of an alkali such as ammonia or an amine.

[Examples]

The present invention will be specifically described below by way of examples and comparative examples, but the present invention is not limited to the following examples. In addition, the following, "parts" and "%" mean the quality basis as long as there are no special exceptions.

(Synthesis of carboxyl group-containing resin A-1)

A polycarbonate diol derived from 1,5-pentanediol and 1,6-hexanediol (T5650J, manufactured by Asahi-Kasei Co., Ltd.) was placed in a reaction vessel equipped with a stirring device, a thermometer, and a condenser. The number average molecular weight was 800) 2400 g (3 mol), dimethylglycolic acid 603 g (4.5 mol), and 2-hydroxyethyl acrylate as a monohydroxy compound (238 g (2.6 mol)). Next, 1887 g (8.5 mol) of isophorone diisocyanate as a polyisocyanate was placed, and the mixture was heated to 60 ° C while stirring, and then stopped, and the temperature in the reaction vessel began to decrease again, and the mixture was further heated at 80 ° C. After confirming that the absorption spectrum (2280 cm ^-1 ) of the isocyanate group in the infrared absorption spectrum disappeared, the reaction was stopped. The carbitol acetate was added to make the solid content 70% by mass. The solid content of the obtained carboxyl group-containing resin had an acid value of 50 mgKOH/g. Hereinafter, the obtained varnish is referred to as a carboxyl group-containing resin solution A-1.

(Modulation of photosensitive resin composition)

The components shown in the following Table 1 were blended in the ratio (parts by mass) shown in the table, and the mixture was prepared by mixing with a stirrer, and then kneaded in three drum mills to prepare a photosensitive resin composition. The degree of dispersion of each photosensitive resin composition obtained here was 15 μm or less after being evaluated by the particle size measurement of the Grind Meter manufactured by Erichsen.

*1: ZFR-1401H (manufactured by Nippon Kayaku Co., Ltd.; solid content 65%)

*2: UN-3320HA (manufactured by Roots Industrial Co., Ltd.; 6-functional urethane acrylate)

*3: UN-904 (manufactured by Kasei Industrial Co., Ltd.; 10-functional urethane propyl acetate Oleate

*4: UN-3320HSBA (manufactured by Roots Industrial Co., Ltd.; 15-functional urethane acrylate)

*5: UN-952 (manufactured by Kokusai Industrial Co., Ltd.; 10-functional urethane acrylate)

*6: UN-905 (manufactured by Kokusai Industrial Co., Ltd.; 15-functional urethane acrylate)

*7: EBECRYL 8405 (manufactured by daicel-allnex; 4-functional urethane acrylate)

*8: Larmer LR8863 (manufactured by BASF Japan Co., Ltd.; polyether modified acrylate oligomer)

*9: LUCIRIN TPO (manufactured by BASF Japan Co., Ltd.; mercaptophosphine oxide photopolymerization initiator)

*10: IRGACURE-OXE-02 (manufactured by BASF Japan Co., Ltd.; oxime ester photopolymerization initiator)

*11: Tipaque CR-97 (manufactured by Ishihara Sangyo Co., Ltd.; rutile-type titanium oxide)

*12: 酞花青蓝

*13: HFA-6065E (made by Showa Denko)

*14: Exolit OP935 (manufactured by Clariant Co., Ltd.) (average particle diameter: 2 to 3 μm)

*15: Higilite H-42M (manufactured by Showa Denko Co., Ltd.) (average particle size: 1 μm)

*16: NC-3000H (manufactured by Nippon Kayaku Co., Ltd.)

*17: YX-4000 (manufactured by Mitsubishi Chemical Corporation)

*18: KS-66 (manufactured by Shin-Etsu Chemical Co., Ltd.)

*19: Disperbyk-111 (BYK.Japan)

*20: Melamine pulverized product

*21: Aerosil #974 (made by EPOCH)

*22: DOWANOL DPM (manufactured by Dow Chemical Co., Ltd.)

<Molecular weight determination of urethane acrylate>

The weight average molecular weight of the urethane acrylate is determined by the GPC method (permeation chromatography) and converted to standard polystyrene. The measurement conditions are shown below.

Device: Waters 2695

Column: Waters HPSgel HR MB-L (6.0mm × 15cm) 2 And Waters HPSgel HR 1.0 (6.0mm × 15cm) 2

Sample dilution method: diluted with 0.5% by mass of tetrahydrofuran

Solvent: tetrahydrofuran

Performance evaluation:

<scratch resistance>

The composition of each of the examples and the comparative examples was completely applied by screen printing onto a 1.6 mm copper solid FR-4 substrate to a dry film thickness of 20 μm, dried at 80 ° C for 30 minutes, and then cooled to room temperature. Thereafter, the exposure device was opened using a contact equipped with an ultrahigh pressure mercury lamp (short arc lamp 5 kW), and the full exposure was performed at the most appropriate exposure amount, and a 1% by mass Na ₂ CO ₃ aqueous solution at 30 ° C was sprayed at 0.2 MPa. The image was developed under the conditions of 120 seconds, and heat-hardened at 150 ° C for 60 minutes to obtain an evaluation sample for forming a cured coating film. The obtained evaluation sample was loaded on a substrate of a 35 μm copper foil on both sides of a 18 μm polyimide film (two-sided copper-coated elastic substrate), and further, a circular shape having a diameter of 12 mm and a smooth bottom surface were carried thereon. 1kg weight. In this state, the double-sided copper-coated elastic substrate was pulled apart in parallel by about 10 cm, and whether or not black marks on the coating film were evaluated by the following criteria.

○: no black marks

△: There are black marks with an amplitude of 1 mm or less.

×: There are black marks with a width of more than 1 mm or a plurality of black marks with an amplitude of 1 mm or less.

<reflectance>

The compositions of the respective examples and comparative examples were completely screen-printed on a 1.6 mm thick copper solid FR-4 substrate, dried at 80 ° C for 30 minutes, and cooled to room temperature. Thereafter, using a contact-disconnected exposure device equipped with an ultra-high pressure mercury lamp (short arc lamp 5 kW), the full exposure was performed at the most appropriate exposure amount, and a 1% by mass Na ₂ CO ₃ aqueous solution at 30 ° C was sprayed at 0.2 MPa. The image was developed under the conditions of 120 seconds, and heat-hardened at 150 ° C for 60 minutes to obtain an evaluation sample for forming a cured coating film. The reflectance (%) at 360 to 740 nm of the surface of the coating film was measured by a spectrophotometer (CM-2600d, manufactured by Konicaminolta Co., Ltd.).

<resolution>

The compositions of the respective examples and comparative examples were completely applied by screen printing onto a 1.6 mm thick copper solid FR-4 substrate to a dry film thickness of 20 μm, dried at 80 ° C for 30 minutes, and cooled to room temperature. For this substrate, a contact-off exposure device equipped with an ultra-high pressure mercury lamp (short-arc lamp 5 kW) is used, and the exposure is performed with the most appropriate exposure amount and a negative pattern having a line width of 100 μm, which is 1 ° 30 ° C. The mass % Na ₂ CO ₃ aqueous solution was developed under the conditions of a spray pressure of 0.2 MPa for 120 seconds, and heat-hardened at 150 ° C for 60 minutes as an evaluation sample. The amplitude of the line removed from the obtained evaluation sample was measured by an optical microscope and evaluated by the following evaluation criteria.

○: The line width of removal is 70μm or more

△: The line width to be removed is 50 μm or more.

×: The line width of removal is less than 50μm

<gloss>

The compositions of the respective examples and comparative examples were completely screen printed on a 1.6 mm thick copper solid FR-4 substrate, dried at 80 ° C for 30 minutes, and cooled to room temperature. Thereafter, using a contact-disconnected exposure device equipped with an ultra-high pressure mercury lamp (short arc lamp 5 kW), the full exposure was performed at the most appropriate exposure amount, and a 1% by mass Na ₂ CO ₃ aqueous solution at 30 ° C was sprayed at 0.2 MPa. The image was developed under the conditions of 120 seconds, and heat-hardened at 150 ° C for 60 minutes to obtain an evaluation sample for forming a cured coating film. For the obtained evaluation sample, a 60-degree specular reflectance was measured using a micro-TRI-gloss (manufactured by BYK. Japan Co., Ltd.).

<flammability>

The compositions of the respective examples and comparative examples were screen-coated on a 25 μm-thick polythene film (Kapton 100H), dried at 80 ° C for 20 minutes, and cooled to room temperature. Further, the inner surface was uniformly coated by screen printing, dried at 80 ° C for 20 minutes, and cooled to room temperature to obtain a double-coated substrate. An exposure apparatus (HMW-680-GW20) equipped with a metal halide lamp was used on the substrate, and the solder resist was fully exposed at the most appropriate exposure amount, and a 1% by mass Na ₂ CO ₃ aqueous solution at 30 ° C was sprayed at 0.2 MPa. The image was developed under the conditions of 120 seconds, and heat-hardened at 150 ° C for 60 minutes as an evaluation sample. For the sample for flame retardancy evaluation, a thin vertical burning test based on the UL94 specification was performed. The evaluation is for the UL94 specification and is expressed as VTM-0 or VTM-1.

<folding>

The compositions of the respective examples and comparative examples were completely screen-coated on a 25 μm-thick polythene film (Kapton 100H manufactured by TORAY. Du Pont), dried at 80 ° C for 30 minutes, and cooled to room temperature. Thereafter, using a contact-disconnected exposure device equipped with an ultra-high pressure mercury lamp (short arc lamp 5 kW), the full exposure was performed at the most appropriate exposure amount, and a 1% by mass Na ₂ CO ₃ aqueous solution at 30 ° C was sprayed at 0.2 MPa. The image was developed under the conditions of 120 seconds, and heat-hardened at 150 ° C for 60 minutes to obtain an evaluation sample in which a cured coating film was formed. The obtained evaluation sample was subjected to a gap of R = 0.8 mm, and then folded 180 times, and the occurrence of cracking in the cured coating film was observed by optical microscopy (magnification × 200). The evaluation benchmark is used for evaluation.

○: No cracking occurs even if it is folded 3 times

△: No crack occurred in 1 time, but crack occurred when folded 2 times to 3 times

×: Cracking occurred when folding once

<Electrical Characteristics>

The composition of the examples and the comparative examples was subjected to full-coating by screen printing using a comb-type electrode B test piece of IPC B-25, and dried at 80 ° C for 30 minutes and cooled to room temperature. Thereafter, the exposure device was disconnected using a contact equipped with an ultra-high pressure mercury lamp (short arc lamp 5 kW), and the entire exposure was performed at the most appropriate exposure amount, and a 1% by mass Na ₂ CO ₃ aqueous solution at 30 ° C was sprayed at 0.2 MPa. The image was developed under the conditions of 120 seconds, and heat-hardened at 150 ° C for 60 minutes to obtain an evaluation sample. A bias voltage of DC 100 V was applied to the comb-shaped electrode, and the presence or absence of displacement of the constant temperature and humidity chamber of 85% RH at 1,000 ° C after 1,000 hours was confirmed, which was evaluated by the following evaluation criteria.

○: I think there is no change at all.

△: only change

×: Displacement occurs

*32: urethane acrylate having a weight average molecular weight of 4,900 and a functional group number of 10 and urethane acrylate having a weight average molecular weight of 50,000 and a functional group of 15

As is apparent from the results shown in the above Tables 1 and 2, in the case of the photosensitive resin composition of the examples, it was difficult to produce a rubbing trace on the cured product. On the other hand, in Comparative Examples 1 and 2 which did not contain (B) a urethane (meth)acrylate having 6 or more functional groups, a rubbing trace was likely to occur on the cured product.

Claims (6)

A photosensitive resin composition comprising (A) a carboxyl group-containing resin, (B) a urethane (meth) acrylate having a functional group number of 6 or more, (C) a photopolymerization initiator, and ( D) Titanium oxide. The photosensitive resin composition of claim 1, wherein the (B) functional group has 6 or more urethane (meth) acrylates having a weight average molecular weight of 1,500 to 200,000. The photosensitive resin composition of claim 1 or 2, further comprising at least one of a metal hydroxide and a phosphorus compound. A dry film obtained by coating and drying a photosensitive resin composition according to any one of claims 1 to 3 on a film. A cured product obtained by hardening a photosensitive resin composition according to any one of claims 1 to 3 or a dry film of claim 4. A printed wiring board characterized by having a cured product as claimed in claim 5.