KR20100024893A - Photopolymer composition, solder resist composition for print circuit boards and print circuit boards - Google Patents

Abstract

PURPOSE: A photoresist resin composition including thiol group compound and a solder resist composition for print circuit boards using thereof are provided to reduce a reflectivity and a discoloration of the level of a white film by a heat hysteresis and a UV irradiation, and to form a pattern with a low exposure amount. CONSTITUTION: A photoresist resin composition contains the following: a monomer selected from the group consisting of acrylic acid and esther acrylate; an active energy ray curing resin reacted with a ring skeleton epoxy having ethylen unsaturated coupling by a carboxyl group of a co-polymer resin from a monomer selected from the group consisting of methacrylic acid and methacrylic acid ester; a thiol based compound; a photo polymerization initiator; a diluents and a rutile type titanium oxide; and a epoxy group thermoplastic compound. The content of the thiol based compound is 0.01~5.0 mass%.

Description

Photosensitive resin composition, soldering resist composition for printed wiring boards and printed wiring boards {PHOTOPOLYMER COMPOSITION, SOLDER RESIST COMPOSITION FOR PRINT CIRCUIT BOARDS AND PRINT CIRCUIT BOARDS}

This invention relates to the photosensitive resin composition, the soldering resist composition for printed wiring boards, and a printed wiring board.

A printed wiring board is for forming a pattern of a conductor circuit on a board | substrate and mounting it by soldering an electronic component to the soldering land of the pattern, The circuit part except this soldering land is coat | covered with the soldering resist film as a permanent protective film. This prevents the solder from adhering to unnecessary portions when soldering the electronic component to the printed wiring board, and prevents the circuit conductor from being directly exposed to air and corroded by oxidation or humidity.

Solder resist compositions also require high resolution and high precision in accordance with the demand for improvement (fineness) of wiring density of printed wiring boards, and excellent positional accuracy and coating properties of conductor edges from screen printing methods for home and industrial substrates. A liquid photo solder resist method (photo development method) has been proposed. Such a soldering resist composition is described in the following literature, for example.

In addition, the alkali image development type photo solder resist composition which can be developed with a dilute alkali aqueous solution is proposed (patent document 7).

These liquid solder resist compositions are provided with photosensitive or developability in an aqueous solution of rare alkali by introducing a carboxyl group into the epoxy acrylate. However, this composition also contains an epoxy compound as a thermosetting component and reacts with a carboxyl group introduced into the epoxy acrylate, in order to normally heat-cure the coating film after exposure and development to form a desired resist pattern. The heat treatment is performed to form a resist film having excellent adhesion, hardness, heat resistance, electrical insulation, and the like. In this case, the hardening | curing agent for epoxy resins is generally used together with an epoxy resin.

[Previous Technical Documents]

[Patent Documents]

Patent Document 1: Japanese Patent Application Laid-open No. 50-144431

Patent Document 2: Japanese Patent Application Laid-open No. 49-5923

Patent Document 3: Japanese Patent Application Laid-Open No. 61-243869

Patent Document 4: Japanese Patent Application Laid-Open No. 2001-233842

Patent Document 5: Japanese Patent Application Laid-Open No. 2001-302871

Patent Document 6: Japanese Patent Application Laid-Open No. 2003-280193

Patent Document 7: Japanese Patent Application Laid-Open No. 2006-259150

Patent Document 8: Japanese Patent Application 2007-047295

However, especially in the case of a white solder resist, when a coating film is heated and hardened | cured, discoloration may arise and may be colored, and light reflectance fell. In the case of a white solder resist, since discoloration and a fall of a reflectance are especially outstanding, there exists a possibility that it may cause a fall in a commodity value, and the solution is calculated | required. On the other hand, the soldering resist composition needs to advance hardening with a comparatively low exposure amount, and there existed a difficult problem which was double | rate.

In order to solve this problem, this applicant disclosed the photosensitive resin composition which has the photosensitive resin which uses a cycloaliphatic skeleton epoxy as a raw material as a main component in patent document 8. However, this composition also had room for further improvement in terms of improvement of discoloration after heating.

An object of the present invention is to provide a liquid resin composition in which the discoloration and reflectance of the white coating film due to UV irradiation and thermal history are small, and the pattern can be formed at a low exposure amount.

The present invention,

(A) An activity in which an alicyclic skeleton epoxy having an ethylenically unsaturated bond is reacted with a carboxyl group of a copolymerizable resin of a monomer selected from the group consisting of acrylic acid and acrylic acid ester and a monomer selected from the group consisting of methacrylic acid and methacrylic acid ester Energy ray curable resin,

(B) thiol compound,

(C) photoinitiator,

(D) diluent,

(E) rutile titanium oxide, and

(F) Epoxy Thermosetting Compound

It relates to a photosensitive resin composition characterized by containing.

Moreover, this invention relates to the soldering resist composition for printed wiring boards which consists of said photosensitive resin composition.

Moreover, this invention relates to the printed wiring board before or after mounting the electronic component which has the cured film of this soldering resist composition.

(Effects of the Invention)

The white coating film formed by the photosensitive resin composition of this invention has little change of the discoloration and reflectance by UV irradiation, a thermal history, and can pattern-form in low exposure amount.

Hereinafter, each component of the composition of this invention is described.

[(A) Alicyclic skeleton epoxy having an ethylenically unsaturated bond is reacted with a carboxyl group of a copolymerizable resin of a monomer selected from the group consisting of acrylic acid and acrylic acid ester and a monomer selected from the group consisting of methacrylic acid and methacrylic acid ester Active energy ray curable resin]

(A) is active energy line curable resin obtained from reaction of the said copolymer and alicyclic skeleton epoxy.

An alicyclic skeleton epoxy is a compound or resin which has an alicyclic skeleton and an epoxy group, and a skeleton is formed of an alicyclic compound or its chain | strand. Although there is no restriction | limiting in particular in epoxy equivalent, Usually, 1,000 or less, Preferably, the thing of 100-500 is used. Cyclohexane and cyclopentane can be illustrated about an alicyclic compound.

In addition, the alicyclic skeleton epoxy has an ethylenically unsaturated bond. This ethylenically unsaturated bond should just be an unsaturated bond of an acryl group and a methacryl group, for example.

As an alicyclic skeletal epoxy, " Celoxide 2021P ", " Celoxide 2000 ", " Celoxide 3000 ", " EHPE3150 ", " EHPE3150CE ", etc. made by Daicel Kagaku Co., Ltd. can be illustrated. In addition, as a compound name-resin name, 3, 4- epoxycyclohexenyl methyl-3, '4'-epoxy cyclohexene carboxylate, vinyl cyclohexene monooxide 1, 2- epoxy-4- vinyl cyclohexane, 1, 2: 8,9 diepoxylimonene, 1,2-epoxy-4- (2-oxyranyl) cyclohexane adduct of 2,2-bis (hydroxymethyl) -1-butanol, 2,2-bis (hydr 1,2-epoxy-4- (2-oxyranyl) cyclohexane adduct of oxymethyl) -1-butanol and 3,4-epoxycyclohexenylmethyl-3, '4'-epoxycyclohexenecarboxylate Can be illustrated.

Moreover, the following can be illustrated as a structural formula of alicyclic skeleton epoxy.

The copolymer resin is obtained by copolymerization of one or two or more monomers selected from the group consisting of acrylic acid and acrylic acid esters with one or two or more monomers selected from the group consisting of methacrylic acid and methacrylic acid esters. It is coalescing.

For example, the copolymer obtained by the copolymerization reaction of acrylic acid and methacrylic acid is shown below.

In addition, the copolymer obtained by the copolymerization reaction of acrylic ester and methacrylic ester is shown below. R is an alkyl group, Preferably it is a methyl group or an ethyl group.

The manufacturing method of the said copolymer is not specifically limited, A conventional method can be used. Moreover, as for the mass mean molecular weight of a copolymer, 10000-30000 are preferable, and, as for the double bond equivalent, 300-500 are preferable.

The copolymer has two or more carboxyl groups in one molecule. Although the number of the carboxyl groups which exist in 1 molecule is not specifically limited, 10-500 pieces are preferable.

Next, the carboxyl group of the copolymer is allowed to react with the epoxy group of the alicyclic skeleton epoxy. Then, an epoxy group cleaves by reaction of an epoxy group and a carboxyl group, and a hydroxyl group and an ester bond are produced | generated as follows. The obtained active energy ray curable resin has an ethylenically unsaturated bond derived from an epoxy group. R ₁ is hydrogen, an alkyl group, or a hydroxyalkyl group, preferably hydrogen or a methyl group.

In reaction of the said copolymer and alicyclic skeletal epoxy, it is preferable to make 0.7-1.2 equivalent react the said copolymer with 1 equivalent of carboxyl groups per 1 equivalent of epoxy group which alicyclic skeleton epoxy has. When the amount of the copolymer is less than 0.7 equivalent by the number of equivalents of the carboxyl group, gelation may occur during the synthesis reaction of the subsequent step, or the stability of the resin is lowered. In addition, when the copolymer is excessive, since many unreacted carboxyl groups remain, there is a concern that various properties (for example, water resistance, etc.) of the cured product are lowered. It is preferable to perform reaction of alicyclic skeletal epoxy and a copolymer in a heating state, and it is preferable that the reaction temperature is 80-140 degreeC. When reaction temperature exceeds 140 degreeC, synthesis | combination may become difficult, and when it is less than 80 degreeC, reaction rate may become slow and it may be undesirable in actual manufacture.

In the reaction in the diluent of an alicyclic skeletal epoxy and a copolymer, it is preferable that the compounding quantity of a diluent is 20 to 50% with respect to the gross mass of a reaction system.

As a specific example of (A), "Cyclomer P (ACA) Z-251", "Cyclomer P (ACA) Z-250", and "Cyclomer P (ACA) Z-300" by Daicel Kagaku Co., Ltd. can be illustrated. have. In addition, "Cyclomer P (ACA) Z-251" by Daicel Kagaku Co., Ltd. is represented by the structural formula of Formula (7) mentioned above.

[(B) Thiol Compound]

It means an organic compound having a thiol group, 3-mercaptopropionic acid, mercaptopropionic acid methoxybutyl, mercaptopropionic acid octyl, mercaptopropionic acid tridecyl, trimetholpropane tristyoproionate, trimetholpropane tris (3 Mercaptopropionate), pentaerythritol tetrakistiopionate, and the like. In particular, the trimetholpropane tristyoplopionate and / or pentaerythritol tetrakistioplopionate are preferable.

[(C) Photopolymerization Initiator]

It will not specifically limit, if it is a photoinitiator used for photocuring of a polyfunctional epoxy resin, It will not specifically limit, An oxime initiator, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin-n-butyl ether, benzoin Isobutyl ether, acetophenone, dimethylaminoacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-1-phenyl Propane-1-one, 1-hydroxycyclohexylphenyl ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propane-1-one, 4- (2-hydroxy Ethoxy) phenyl-2- (hydroxy-2-propyl) ketone, benzophenone, p-phenylbenzophenone, 4,4'-diethylaminobenzophenone, dichlorobenzophenone, 2-methylanthraquinone, 2-ethyl Anthraquinone, 2-tert-butylanthraquinone, 2-aminoanthraquinone, 2-methylthioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4 Diethyl thioxanthone, ben Dimethyl ketal, acetophenone dimethyl ketal, p-dimethylaminobenzoic acid ethyl ester, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, etc. are mentioned. Can be. These can be used individually or in combination.

[(D) Diluent]

(D) A diluent consists of 1 or more types of a photopolymerizable monomer and an organic solvent. A photopolymerizable monomer is also called a reactive diluent, and it is used in order to make photocuring of the photosensitive resin of the said (A) component more sufficient, and to obtain the coating film which has acid resistance, heat resistance, alkali resistance, etc. The reactive diluent is preferably a compound having two or more double bonds in one molecule. In order to adjust the viscosity and dryness of the composition containing the photosensitive resin of the said (A) component, you may use the organic solvent which is a non-reactive diluent, but if it is not necessary, you may not use an organic solvent. In addition, when the photocurability of only the photosensitive resin (A) is sufficient, the photopolymerizable monomer may not be used.

As typical examples of this photopolymerizable monomer (reactive diluent), for example, 1,4-butanediol di (meth) acrylate, 1,6-hexanedioldi (meth) acrylate, neopentylglycol di (meth) acrylate , Polyethylene glycol di (meth) acrylate, neopentyl glycol adipate di (meth) acrylate, hydroxypivalic acid neopentyl glycol di (meth) acrylate, dicyclopentanyldi (meth) acrylate, caprolactone modified dish Clopentenyldi (meth) acrylate, ethylene oxide modified phosphoric acid di (meth) acrylate, allylated cyclohexyldi (meth) acrylate, isocyanurate di (meth) acrylate, trimetholpropane tree (meth) Acrylate, dipentaerythritol tri (meth) acrylate, propionic acid-modified dipentaerythritol tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pro Phenylene oxide modified trimetholpropane tri (meth) acrylate, tris (acryloxyethyl) isocyanurate, propionic acid modified dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, caprolactone Reactive diluents, such as modified dipentaerythritol hexa (meth) acrylate, are mentioned.

The polyfunctional reactive diluent other than the said 2-6 functional other than that can be used in any one or a plurality of mixed systems. As for the addition amount of this reactive diluent, 2.0-40 mass parts is preferable with respect to 100 mass parts of (A) photosensitive resin. If the addition amount is too small, sufficient photocuring cannot be obtained, and sufficient properties are not obtained in acid resistance of the cured coating film, and if too large, the adhesiveness is severe, and adhesion of the artwork film to the substrate during exposure is likely to occur. It is difficult to obtain a cured coating film. The addition amount of the reactive diluent is more preferably 4.0 to 30 parts by mass with respect to 100 parts by mass of the (A) photosensitive resin from the viewpoints of physical properties such as photocurability, acid resistance of the cured coating film, heat resistance, and adhesion to the artwork film substrate.

As said organic solvent, For example, ketones, such as methyl ethyl ketone and cyclohexanone, aromatic hydrocarbons, such as toluene and xylene, alcohols, such as methanol, isopropanol, cyclohexanol, alicyclic type, such as cyclohexane and methylcyclohexane Petroleum solvents such as hydrocarbons, petroleum ether, petroleum naphtha, cellosolves such as cellosolve and butyl cellosolve, carbitols such as carbitol and butyl carbitol, ethyl acetate, butyl acetate, cellosolve acetate, Acetic esters, such as butyl cellosolve acetate, carbitol acetate, and butyl carbitol acetate, etc. are mentioned. When using an organic solvent, it is preferable that the usage-amount is 40-500 mass parts with respect to 100 mass parts of (A) photosensitive resin.

[(E) Rutile Titanium Oxide]

It is titanium oxide particle which has a rutile crystal structure, and whitens a coating film. Although the average particle diameter of this particle | grain is not specifically limited, What is necessary is just 0.01-1 micrometer. Further, the surface treatment of the rutile titanium oxide particles is also not limited.

[(F) Epoxy Thermosetting Compound]

The photosensitive resin composition WHEREIN: It adds in order to acquire the coating film (coating film strength, heat resistance, durability, chemical resistance, environmental resistance, etc.) which is sufficiently strong after the postcure after exposing and developing the coating film.

As a typical example of an epoxy type thermosetting compound, although the epoxy resin (including epoxy oligomer) which has 1 or more epoxy groups, Preferably 2 or more epoxy groups in 1 molecule is suitable, it is not limited to this. For example, a bisphenol A type epoxy resin obtained by reacting bisphenol A with epichlorohydrin in the presence of alkali, an epoxide of a resin obtained by condensation reaction of bisphenol A with formalin, and brominated bisphenol A instead of bisphenol A in these resins. Novolak-type epoxy resin (glycol novolak-type epoxy resin, o-cresol novolak-type epoxy resin, p-tert-butylphenol novolak type) which glycidyl-etherified by making epichlorohydrin react with novolak resin And bisphenol F or bisphenol S type epoxy resins obtained by reacting bisphenol F or bisphenol S with epichlorohydrin, and alicyclic epoxy resins having a cyclohexene oxide group, a tricyclodecane oxide group, a cyclopentene oxide group, and the like. Phthalic acid diglycidyl ester, tetrahydrophthalic acid diglycidyl ester, hexahydrophthalic acid di Glycidyl ester resins such as lycidyl ester, diglycidyl-p-hydroxybenzoic acid, dimer acid glycidyl ester, and glycidyl esters such as tetraglycidyl diaminodiphenylmethane and triglycidyl-p-aminophenol Cidylamine resin, (propylene, polypropylene) glycol diglycidyl ether, polytetramethylene glycol diglycidyl ether, glycerol polyglycidyl ether, trimetholpropane polyglycidyl ether, resorcin diglycyl Cylyl ether, 1,6 hexanediol diglycidyl ether, (ethylene, propylene) glycol diglycidyl ether, sorbitol polyglycidyl ether, sorbitan polyglycidyl ether, pentaerythritol polyglycidyl ether, etc. Triglycidyl isocyanurate which has triazine ring, such as glycidyl ether resin, tris (2, 3- epoxypropyl) isocyanurate, and triglycidyl tris (2-hydroxyethyl) isocyanurate Agent, and the like can be mentioned dicyclopentadiene type epoxy resin. The thermosetting compound (F) may be used alone or in combination of two or more.

In the photosensitive resin composition which concerns on this invention, it is preferable that content of (A) active energy ray curable resin is 10-50 mass%.

Moreover, it is preferable to make content of the (B) thiol type compound into 0.01 mass% or more, and the prevention effect, such as discoloration of a white coating film, becomes further high by this. From this point of view, the content of the thiol compound (B) is more preferably 0.5% by mass or more, and more preferably 1.0% by mass or more. In addition, the content of the thiol-based compound (B) is preferably 5.0% by mass or less, and there is no fear of adversely affecting the storage stability of the solder resist. From such a viewpoint, it is more preferable to set it as 2.0 mass% or less.

In the composition of the present invention, the mass ratio of the (C) photopolymerization initiator is preferably 0.1 to 10.0 mass%, more preferably 0.2 to 5.0 mass%.

In the composition of the present invention, the mass ratio of the diluent (D) is preferably 1.0 to 10.0 mass%, more preferably 3.0 to 6.0 mass%.

In the composition of this invention, the whiteness of a coating film can be improved by making the mass ratio of (E) rutile type titanium oxide into 5 mass% or more. From this point of view, the mass ratio of (E) is more preferably at least 20 mass%, more preferably at least 30 mass%. Moreover, even if the mass ratio of (E) exceeds 50 mass%, since whiteness does not become high and there exists a bad influence in terms of intensity | strength, etc., the mass ratio of (E) is preferable 50 mass% or less, and 40 mass% or less is more preferable. .

In the composition of the present invention, the mass ratio of the (F) epoxy-based thermosetting compound is preferably 1.0 to 30% by mass, more preferably 5.0 to 20% by mass.

The photosensitive resin composition of this invention can contain various additives, for example, additives for paints, such as an antifoamer and a leveling agent, etc. other than the said components (A)-(F) as needed.

(A)-(F) and other components are mixed as needed, and kneading | mixing by mixing means, such as a three-roll, a ball mill, a sand mill, or stirring means, such as a super mixer and a planetary mixer, as needed. It mixes and the photosensitive resin composition of this invention is obtained.

The photosensitive resin composition of this invention obtained as mentioned above is apply | coated to the printed wiring board which has a pattern of the circuit formed by etching the copper foil of a copper clad laminated board, for example with desired thickness, for example, thickness of 5-100 micrometers. As a means of coating, the whole surface printing by the screen printing method is generally used now, but what kind of means may be used as long as it is a coating means which can coat uniformly including this. For example, spray coater, hot melt coater, bar coater, applicator, blade coater, knife coater, air knife coater, curtain flow coater, roll coater, gravure coater, offset printing, dip coater, brush coating, and other conventional methods Both can be used.

After coating, it is prebaked in a hot stove, a far-infrared furnace, etc. as needed, ie, temporary drying is performed, and the surface of a coating film is made tack-free. As for the temperature of a prebaking, about 50-100 degreeC is preferable.

Next, exposure by laser direct drawing using LDI (Laser Direct Imaging) is performed. Alternatively, exposure by the active energy ray is performed using a negative mask which does not allow the active energy ray to pass therethrough. As a negative mask, a negative film is used when the active energy ray is an ultraviolet ray, a metallic mask is used when the electron beam is used, and a lead mask is used when the X ray is used. It is used a lot. The irradiation amount of ultraviolet rays is approximately 10 to 1000 mJ / cm 2.

In the case of manufacturing a printed wiring board, exposure is performed, for example, by contact | adhering the negative film of the pattern made transparent, except for the soldering land of a circuit pattern, and irradiating an ultraviolet-ray from the top, but a non-exposed area | region corresponding to this soldering land is made white. The coating film is developed by removing with aqueous alkali solution. This removal may be any of dissolution, swelling, and peeling of the unexposed portion. As the rare alkali aqueous solution used at this time, 0.5-5% of sodium carbonate aqueous solution is common, but other alkali can also be used.

Subsequently, when it contains a thermosetting compound, it post-cures by heating for 20 to 80 minutes or ultraviolet-ray irradiation, for example in a dryer, such as a 130-170 degreeC hot-air furnace or a far-infrared furnace, and solder resist by this. A film can be formed.

In this way, a printed wiring board coated with a solder resist film is obtained, and electronic components are connected and fixed by being mounted by soldering by the flow soldering method or the reflow soldering method, thereby forming one electronic circuit unit. .

In this invention, the object includes both the printed wiring board which coat | covered the soldering resist film before electronic component mounting, and the printed wiring board after electronic component mounting which mounted the electronic component on this printed wiring board.

EXAMPLE

(Example 1)

Each component was mixed by the following mass ratio, and the soldering resist composition was produced. Detailed component amounts are shown below.

(A) 40 mass% of "cyclomer P (ACA) Z-251" made by Daicel Kagaku Co., Ltd.

(B) 0.05% by mass of trimetholpropane tristyoproionate

0.3 mass% of (C) acyl phosphine-type photoinitiator ("IRGACURE 819" made by Chiba specialty chemicals)

(D) 5 mass% of diluents (DPHA)

(E) rutile type titanium oxide ("CR-80" made by Ishihara Sanga) 35 mass%

(F) 10 mass% of epoxy-type thermosetting compounds ("EPICLON 860" made by Dainippon Ink & Chemical Co., Ltd.)

Balance

Defoamer, KS-66 (made by Shin-Etsu Silicone Co., Ltd.)

Thixotropic agent, AEROSIL R-97 (product made by Nippon Aerosil)

DICY-7 (product made in Japan epoxy resin company)

Ako Solve DPM (made by Kyowa Hakko Teacher)

EDGAC (made by Daisel Kagaku Teacher)

Solvetso 150 (made by ExxonMobil)

Talc

Barium sulfate

Melamine

(Example 2)

The composition of the following compositions was produced by the method similar to Example 1. However, it is the same as Example 1 except (A)-(F).

(A) 40 mass% of "cyclomer P (ACA) Z-251" made by Daicel Kagaku Co., Ltd.

(B) 1% by mass of trimetholpropane tristyoproionate

0.3 mass% of (C) acyl phosphine-type photoinitiator ("IRGACURE 819" made by Chiba specialty chemicals)

(D) 5 mass% of diluents (DPHA)

(E) rutile type titanium oxide ("CR-80" made by Ishihara Sanga) 35 mass%

(F) 10 mass% of epoxy-type thermosetting compounds ("EPICLON 860" made by Dainippon Ink & Chemical Co., Ltd.)

(Example 3)

The composition of the following compositions was produced by the method similar to Example 1. However, it is the same as Example 1 except (A)-(F).

(A) 40 mass% of "cyclomer P (ACA) Z-251" made by Daicel Kagaku Co., Ltd.

(B) 5% by mass of trimetholpropane tristyoproionate

0.3 mass% of (C) acyl phosphine-type photoinitiator ("IRGACURE 819" made by Chiba specialty chemicals)

(D) 5 mass% of diluents (DPHA)

(E) rutile type titanium oxide ("CR-80" made by Ishihara Sanga) 35 mass%

(F) 10 mass% of epoxy-type thermosetting compounds ("EPICLON 860" made by Dainippon Ink & Chemical Co., Ltd.)

(Example 4)

The composition of the following compositions was produced by the method similar to Example 1. However, it is the same as Example 1 except (A)-(F).

(A) 40 mass% of "cyclomer P (ACA) Z-251" made by Daicel Kagaku Co., Ltd.,

(B) 1 mass% of pentaerythritol tetrakistiopionate

0.3 mass% of (C) acyl phosphine system photoinitiator ("DAROCUR 819" made by Chiba Specialty Chemicals)

(D) 5 mass% of diluents (DPHA)

(E) rutile type titanium oxide ("CR-80" made by Ishihara Sanga) 35 mass%

10 mass% of epoxy type thermosetting compounds ("EPICLON 860" made by Dainippon Ink & Chemical Co., Ltd.)

(Example 5)

The composition of the following compositions was produced by the method similar to Example 1. However, it is the same as Example 1 except (A)-(F).

(A) 40 mass% of "cyclomer P (ACA) Z-251" made by Daicel Kagaku Co., Ltd.,

(B) 1% by mass of trimetholpropane tristyoproionate,

0.3 mass% of (C) acyl phosphine type photoinitiators ("IRGACURE TPO" made by Chiba Specialty Chemicals)

(D) 5 mass% of diluents (DPHA)

(E) Rutile titanium oxide (CR-80, manufactured by Ishihara Sangyo Co., Ltd.) 35 mass%

(F) 10 mass% of epoxy-type thermosetting compounds ("jER 807" made by Japan Epoxy Resin company)

(Comparative Example 1)

The composition of the following compositions was produced by the method similar to Example 1. However, (A)-(F) of Example 1 was replaced with the following.

(G) 40 mass% of active energy ray curable resin made to react from alicyclic skeletal epoxy resin ("EHPE-3150" by Daicel Chemical Co., Ltd.).

(B) does not contain trimetholol propane tristyropropionate

0.3 mass% of (C) acyl phosphine-type photoinitiator ("IRGACURE 819" made by Chiba specialty chemicals)

(D) 5 mass% of diluents (DPHA)

(E) rutile type titanium oxide ("CR-80" made by Ishihara Sanga) 35 mass%

(F) 10 mass% of epoxy-type thermosetting compounds ("EPICLON 860" made by Dainippon Ink & Chemical Co., Ltd.)

(Comparative Example 2)

The composition of the following compositions was produced by the method similar to Example 1. However, (A)-(F) of Example 1 was replaced with the following.

(G) 40 mass% of active energy ray curable resin reacted from alicyclic skeletal epoxy (for example, Daicel Chemical Co., Ltd. make, EHPE-3150)

(B) 1% by mass of trimetholpropane tristyoproionate

0.3 mass% of (C) acyl phosphine-type photoinitiator ("IRGACURE 819" made by Chiba specialty chemicals)

(D) 5 mass% of diluents (DPHA)

(E) rutile type titanium oxide ("CR-80" made by Ishihara Sanga) 35 mass%

10 mass% of (F) epoxy type thermosetting compounds ("EPICLON N-860" made by Dainippon Ink & Chemical Co., Ltd.)

Each compound of an Example and a comparative example was mixed and dispersed by three rolls, and the photosensitive resin composition was prepared. Table 1 shows the results of sensitivity, line residue, discoloration and reflectance of the coating film of this composition.

The board | substrate preparation process and evaluation method at the time of performing these evaluations are as follows.

Surface Treatment: Buff Polishing

Coating: Coating film thickness: Dry 20 to 23 µm

Pre-drying: 75 ℃ -20 minutes [25 minutes in the box furnace]

Exposure: Resist image: 300 mJ / cm 2 (HMW-680GW manufactured by Oak Corporation)

Developing: 1% Na ₂ CO ₃ -30 ℃ -0.1MPa · s × 90 seconds

Post Cure: 150 ℃ -60 minutes (70 minutes in box type furnace)

Discoloration evaluation: Visually evaluate discoloration of the cured coating film after heating at 260 ° C. for 90 minutes.

Reflectance rating: showing 450nm reflectance

After irradiation: The reflectance of the cured coating film was measured after UV irradiation (150J), in which a wavelength of 400 nm or less was cut by the filter.

After heating: Measure the reflectance of the cured coating film after heating for 90 minutes at 260 ℃

Sensitivity :

Using the 21-step step tablet as a test plate, the photosensitive resin composition of each of the above examples was coated by a screen printing method to a thickness of about 35 μm (before drying), dried to prepare respective coated substrates, and at an irradiation dose of 400 mJ / cm 2. Ultraviolet exposure was performed, 90 second development was carried out using a 1% sodium carbonate aqueous solution at a spray pressure of 0.1 MPa · s, and the coating film was evaluated at the maximum number of steps remaining completely. The larger the number of steps, the better the photosensitive characteristic.

Line residue: A copper foil having a QFP pattern having a thickness of 50 µm as a test plate, coating the photosensitive resin composition of each of the above examples by a screen printing method with a thickness of 35 µm (before drying), and drying the coating film to each coated substrate Is produced and ultraviolet-ray exposure is performed by the irradiation amount of 400mJ / cm <2>. At that time, an exposure film having a line width of 40 to 150 µm and divided into 10 µm units is used. The development was carried out for 90 seconds at a spray pressure of 0.1 MPa · s using an aqueous 1% sodium carbonate solution, and the minimum line width remaining of the coating film was evaluated. The smaller the line width, the better the photosensitive characteristic.

In Examples 1, 2, 3, 4, and 5, it is understood that there is little line residue, the discoloration of the white coating film is suppressed, and the change in reflectance after heating after irradiation is also small.

On the other hand, in Comparative Examples 1 and 2, the line remaining is relatively inferior, the discoloration of the white coating film is large, and the change in reflectance after heating is also large. That is, in this Example, it turns out that internal photosensitive property is favorable, the discoloration of a white coating film, and the fall of reflectance after heating are suppressed, and the commodity value of a soldering resist composition improves remarkably.

Claims (5)

(A) an active energy in which an alicyclic skeleton epoxy having an ethylenically unsaturated bond is reacted with a carboxyl group of a copolymerizable resin of a monomer selected from the group consisting of acrylic acid and acrylic acid ester and a monomer selected from the group consisting of methacrylic acid and methacrylic acid ester Line curable resin, (B) thiol compound, (C) photoinitiator, (D) diluent, (E) rutile titanium oxide, and (F) The epoxy photocurable compound is contained, The photosensitive resin composition characterized by the above-mentioned. Content of the said (B) thiol type compound is 0.01-5.0 mass%, The photosensitive resin composition of Claim 1 characterized by the above-mentioned. The photosensitive resin composition according to claim 1 or 2, wherein the thiol-based compound (B) contains at least one of trimetholol propane tristyropropionate and pentaerythritol tetrakistioplopionate. It consists of the photosensitive resin composition of any one of Claims 1-3, The soldering resist composition for printed wiring boards characterized by the above-mentioned. It has a cured film of the soldering resist composition of Claim 4, The printed wiring board before mounting or after mounting an electronic component.