JP6594468B2 - Photosensitive resin composition, dry film, cured product, and printed wiring board - Google Patents

Description

  The present invention relates to a photosensitive resin composition, a dry film, a cured product, and a printed wiring board, and more specifically, a photosensitive resin composition excellent in resolution and storage stability, and a dry film having a resin layer made of the composition. The invention relates to a cured product of the resin layer of the composition or the dry film, and a printed wiring board having the cured product.

  Due to rapid progress of semiconductor components in recent years, electronic devices tend to be smaller, lighter, higher performance, and multifunctional. Following this trend, printed wiring boards are also becoming increasingly dense and surface-mounted. In the production of high-density printed wiring boards, photosensitive resin compositions used for forming solder resist layers and the like have been developed. Among these, in consideration of environmental problems, an alkali development type photosensitive resin composition using a dilute alkaline aqueous solution as a developing solution has become the mainstream, and conventionally, a carboxyl group-containing resin has been used to impart alkali developability. Various composition systems used have been proposed (for example, Patent Document 1). In addition, the epoxy resin is further blended, and the properties of the cured product, such as heat resistance and chemical resistance, are improved by using a thermal reaction between the carboxyl group and the epoxy group to be cured (for example, Patent Document 2).

JP-A 61-243869 JP-A-5-158240

  In the photosensitive resin composition, a colorant is blended depending on the application and purpose. However, since the colorant (especially black colorant) has light absorptivity, it prevents light from penetrating to the deep part, and is also refracted like a white colorant such as titanium oxide. When many colorants having a high rate are included, the light is reflected even after exposure, so there is room for improvement in resolution.

  In addition, when an epoxy resin is blended, in order to prevent the curing reaction from proceeding at the time of storage, the main component containing a carboxyl group-containing resin and a curing agent containing an epoxy resin are stored separately, and they are used during use. Are often used as so-called two-component photosensitive resin compositions. However, in a two-part photosensitive resin composition, when a photocurable monomer that is a component for imparting or accelerating photocurability is contained in a curing agent containing an epoxy resin and stored, the storage stability is improved. There was room for improvement.

  Accordingly, an object of the present invention is to provide a photosensitive resin composition excellent in resolution and storage stability, a dry film having a resin layer made of the composition, a cured product of the composition or the resin layer of the dry film, and It is providing the printed wiring board which has this hardened | cured material.

  As a result of intensive studies to solve the above problems, the present inventor contains dipentaerythritol hexa (meth) acrylate and dipentaerythritol penta (meth) acrylate as photocurable monomers, and dipentaerythritol hexa ( The inventors have found that the above problem can be solved by setting the content ratio of the (meth) acrylate to a certain level or more, and have completed the present invention.

  That is, the photosensitive resin composition of the present invention comprises (A) a carboxyl group-containing resin, (B) a photopolymerization initiator, (C) a photocurable monomer, (D) a colorant, and (E) in one molecule. A photosensitive resin composition containing an epoxy resin having two or more epoxy groups, wherein (C-1) dipentaerythritol hexa (meth) acrylate as the (C) photocurable monomer, and ( C-2) It contains dipentaerythritol penta (meth) acrylate, and the ratio of (C-1) is 60% by mass or more per the sum of (C-1) and (C-2). It is what.

  In the photosensitive resin composition of the present invention, the (D) colorant is preferably at least one of a white colorant and a black colorant.

  The photosensitive resin composition of the present invention comprises at least a main component containing (A) a carboxyl group-containing resin, at least (C) a photocurable monomer, and (E) two or more epoxy groups in one molecule. It is preferable that it is two-component which consists of a hardening | curing agent containing the epoxy resin which has.

  The dry film of the present invention is characterized by having a resin layer made of the photosensitive resin composition.

  The cured product of the present invention is characterized in that the photosensitive resin composition or the resin layer of the dry film is obtained by at least one of thermosetting and photocuring.

  The printed wiring board of this invention has the said hardened | cured material, It is characterized by the above-mentioned.

  According to the present invention, a photosensitive resin composition excellent in resolution and storage stability, a dry film having a resin layer comprising the composition, a cured product of the composition or a resin layer of the dry film, and the cured product It is possible to provide a printed wiring board having

  The photosensitive resin composition of the present invention comprises (A) a carboxyl group-containing resin, (B) a photopolymerization initiator, (C) a photocurable monomer, (D) a colorant, and (E) 2 in one molecule. A photosensitive resin composition containing an epoxy resin having at least one epoxy group, wherein (C-1) dipentaerythritol hexa (meth) acrylate (hereinafter simply referred to as “( C-1) ”) and (C-2) dipentaerythritol penta (meth) acrylate (hereinafter also simply referred to as“ (C-2) ”), The ratio of (C-1) is 60% by mass or more per total sum of C-2). By blending (C-1) and (C-2) at such a ratio, a photosensitive resin composition having excellent resolution can be obtained in spite of containing the colorant (D). . Further, when a two-component photosensitive resin composition is used, storage of a curing agent containing at least (C) a photocurable monomer and (E) an epoxy resin having two or more epoxy groups in one molecule. Excellent stability. Here, “(meth) acrylate” is a generic term for acrylate, methacrylate, and mixtures thereof, and the same applies to other similar expressions in the present specification. Hereinafter, each component will be described in detail.

[(A) Carboxyl group-containing resin]
The photosensitive resin composition of the present invention contains (A) a carboxyl group-containing resin. (A) As a carboxyl group-containing resin, a resin containing a known carboxyl group can be used. Due to the presence of the carboxyl group, the resin composition can be rendered alkali developable. Further, from the viewpoint of making the photosensitive resin composition of the present invention photocurable and developing resistance, it is preferable to have an ethylenically unsaturated bond in the molecule in addition to the carboxyl group. A carboxyl group-containing resin having no double bond can also be used. As the ethylenically unsaturated double bond, those derived from acrylic acid, methacrylic acid or derivatives thereof are preferable.

  Specific examples of the carboxyl group-containing resin that can be used in the photosensitive resin composition of the present invention include compounds listed below (any of oligomers and polymers).

(1) a carboxyl group-containing copolymer resin obtained by copolymerizing an unsaturated carboxylic acid such as (meth) acrylic acid and one or more other compounds having an unsaturated double bond;
(2) Glycidyl (meth) acrylate or 3,4-epoxycyclohexyl is a copolymer of an unsaturated carboxylic acid such as (meth) acrylic acid and one or more other compounds having an unsaturated double bond. A carboxyl group-containing photosensitive resin obtained by adding an ethylenically unsaturated group as a pendant by a compound having an epoxy group and an unsaturated double bond, such as methyl (meth) acrylate, or (meth) acrylic acid chloride,
(3) Copolymerization of a compound having an unsaturated double bond with an epoxy group such as glycidyl (meth) acrylate or 3,4-epoxycyclohexylmethyl (meth) acrylate, and a compound having an unsaturated double bond other than that A carboxyl group-containing photosensitive resin obtained by reacting an unsaturated carboxylic acid such as (meth) acrylic acid with the coalescence and reacting a polybasic acid anhydride with the generated secondary hydroxyl group,
(4) To a copolymer of an acid anhydride having an unsaturated double bond such as maleic anhydride and a compound having an unsaturated double bond other than that, a hydroxyl group such as 2-hydroxyethyl (meth) acrylate; A carboxyl group-containing photosensitive resin obtained by reacting a compound having an unsaturated double bond,
(5) a carboxyl group-containing photosensitive resin obtained by reacting a polyfunctional epoxy compound with an unsaturated monocarboxylic acid and reacting the generated hydroxyl group with a saturated or unsaturated polybasic acid anhydride,
(6) After reacting a hydroxyl-containing polymer such as a polyvinyl alcohol derivative with a saturated or unsaturated polybasic acid anhydride, the resulting carboxylic acid is reacted with an epoxy group and an unsaturated double bond in one molecule. Hydroxyl group- and carboxyl group-containing photosensitive resin obtained by
(7) a polyfunctional epoxy compound, an unsaturated monocarboxylic acid, at least one alcoholic hydroxyl group in one molecule, and a compound having one reactive group other than an alcoholic hydroxyl group that reacts with an epoxy group A carboxyl group-containing photosensitive resin obtained by reacting a reaction product with a saturated or unsaturated polybasic acid anhydride,
(8) Saturated or unsaturated polybasic with respect to the primary hydroxyl group in the modified oxetane resin obtained by reacting an unsaturated monocarboxylic acid with a polyfunctional oxetane compound having at least two oxetane rings in one molecule. A carboxyl group-containing photosensitive resin obtained by reacting an acid anhydride, and
(9) A carboxylic acid-containing resin obtained by reacting an unsaturated monocarboxylic acid with a polyfunctional epoxy resin and then reacting with a polybasic acid anhydride further contains one oxirane ring and one or more in the molecule. Examples thereof include, but are not limited to, a carboxyl group-containing photosensitive resin obtained by reacting a compound having an ethylenically unsaturated group.

  Among these examples, preferred are the carboxyl group-containing resins of (2), (5) and (9) above. Particularly, the carboxyl group-containing photosensitive resin of (2) is photocurable and cured. It is preferable from the viewpoint of coating film characteristics.

Since the carboxyl group-containing resin as described above has many carboxyl groups in the side chain of the backbone polymer, development with a dilute alkaline aqueous solution becomes possible.
The acid value of the carboxyl group-containing resin is desirably in the range of 20 to 200 mgKOH / g, more preferably in the range of 40 to 150 mgKOH / g. When it is in the range of 20 to 200 mgKOH / g, adhesion of the coating film is obtained, alkali development is facilitated, dissolution of the exposed portion by the developer is suppressed, the line does not fade more than necessary, and exposure is performed. It is preferable because dissolution and peeling with a developer can be suppressed without distinction between a part and an unexposed part, and a normal resist pattern can be easily drawn.

  The weight average molecular weight of the carboxyl group-containing resin used in the present invention varies depending on the resin skeleton, but is preferably in the range of 1,000 to 100,000. When in this range, the tack-free performance is good, the moisture resistance of the coated film after exposure is good, the film is not easily reduced during development, the resolution is improved, the developability is good, and the storage stability is good. Become. More preferably, it is 2,000-70,000. The weight average molecular weight can be measured by gel permeation chromatography.

[(B) Photopolymerization initiator]
It does not specifically limit as (B) photoinitiator contained in the photosensitive resin composition of this invention, A well-known photoinitiator can be used. For example, benzoins such as benzoin, benzyl, benzoin methyl ether, benzoin ethyl ether, benzoin n-propyl ether, benzoin isopropyl ether, benzoin n-butyl ether; benzoin alkyl ethers; benzophenone, p-methylbenzophenone, Michler's ketone, methylbenzophenone, Benzophenones such as 4,4′-dichlorobenzophenone and 4,4′-bisdiethylaminobenzophenone; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloro Acetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-1-pro Non, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1, N, N-dimethylaminoacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, etc. Acetophenones; 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, thioxanthones such as 2,4-diisopropylthioxanthone; anthraquinone, chloroanthraquinone, 2-methylanthraquinone, 2-ethylanthraquinone, 2 -Anthraquinones such as tert-butylanthraquinone, 1-chloroanthraquinone, 2-amylanthraquinone, 2-aminoanthraquinone; ketals such as acetophenone dimethyl ketal and benzyldimethyl ketal; -Benzoic acid esters such as dimethylaminobenzoate, 2- (dimethylamino) ethylbenzoate, p-dimethylbenzoic acid ethyl ester; 1,2-octanedione, 1- [4- (phenylthio)-, 2- (O- Benzoyloxime)], ethanone, oxime esters such as 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (O-acetyloxime); bis (η5 -2,4-cyclopentadien-1-yl) -bis (2,6-difluoro-3- (1H-pyrrol-1-yl) phenyl) titanium, bis (cyclopentadienyl) -bis [2,6- Titanocenes such as difluoro-3- (2- (1-pyryl-1-yl) ethyl) phenyl] titanium; 2,4,6-trimethylbenzoyldiphe Acylphosphine oxides such as ruphosphine oxide and bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide; butyroin, anisoin ethyl ether, azobisisobutyronitrile, tetramethylthiuram disulfide, etc. . (B) A photoinitiator can be used individually by 1 type or in combination of 2 or more types.

  (B) Although the compounding quantity of a photoinitiator is not specifically limited, Preferably it is 0.1-20 mass parts with respect to 100 mass parts of (A) carboxyl group-containing resin, More preferably, it is 0.3-15 mass parts. Included in the ratio. Moreover, the photoinitiator and a sensitizer can be mix | blended with the photosensitive resin composition of this invention. Examples of the photoinitiator aid include tertiary amines, and examples of the sensitizer include coumarins.

[(C) Photocurable monomer]
The photosensitive resin composition of the present invention comprises (C-1) dipentaerythritol hexa (meth) acrylate and (C-2) dipentaerythritol penta (meth) acrylate as the (C) photocurable monomer. And the ratio of (C-1) per 60% by mass or more per total of (C-1) and (C-2). Further, the ratio of (C-1) is preferably 99% by mass or less per the sum of (C-1) and (C-2). In the case of 60-90 mass%, since developability and resolution become favorable, it is more preferable.

  In the present invention, as (C-1) and (C-2), a mixture of commercially available dipentaerythritol hexa (meth) acrylate and dipentaerythritol penta (meth) acrylate is mixed in one kind or two or more kinds. In the photosensitive resin composition, dipentaerythritol hexa (meth) acrylate as a compound may be used in an amount of 60% by mass or more per sum of dipentaerythritol hexa (meth) acrylate and dipentaerythritol penta (meth) acrylate. As long as it is contained.

  As (C-1), dipentaerythritol hexaacrylate is preferable. As (C-2), dipentaerythritol pentaacrylate is preferable.

  10-70 mass parts is preferable with respect to 100 mass parts of (A) carboxyl group-containing resin, and, as for the total amount of said (C-1) and (C-2), 20-60 mass parts is more preferable. Moreover, the photosensitive resin composition of this invention is within the range which does not impair the effect of this invention, As a photocurable monomer other than said (C-1) and (C-2), one piece in a molecule | numerator You may contain the other compound which has the above ethylenically unsaturated group.

[(D) Colorant]
The photosensitive resin composition of the present invention contains a colorant. (D) As the colorant, conventionally known colorants such as white, black, red, blue, green, yellow, purple, orange, and brown can be used, and any of pigments, dyes, and pigments may be used. As a specific example, a color index (CI; issued by The Society of Dyers and Colorists) number is given. However, it is preferable not to contain a halogen from the viewpoint of reducing the environmental burden and affecting the human body. In the present invention, when the colorant (D) is a white or black colorant, the resolution can be remarkably improved.

White colorant:
Examples of the white colorant include titanium oxide, zinc oxide, basic lead carbonate, basic lead sulfate, lead sulfate, zinc sulfide, and antimony oxide. Titanium oxide may be rutile titanium oxide or anatase titanium oxide, but rutile titanium oxide is preferably used. Anatase-type titanium oxide, which is the same titanium oxide, has a higher whiteness than rutile-type titanium oxide and is often used as a white pigment. The emitted light may cause discoloration of the resin in the insulating resin composition. In contrast, rutile-type titanium oxide is slightly inferior in whiteness to anatase-type, but has almost no photoactivity. Therefore, resin degradation due to light caused by photoactivity of titanium oxide (yellowing) Is remarkably suppressed and is stable against heat. For this reason, when it is used as a white pigment in the insulating layer of the printed wiring board on which the LED is mounted, a high reflectance can be maintained over a long period of time.

  A well-known thing can be used as a rutile type titanium oxide. There are two types of production methods for rutile titanium oxide, a sulfuric acid method and a chlorine method. In the present invention, those produced by any of the production methods can be suitably used. Here, the sulfuric acid method uses ilmenite ore or titanium slag as a raw material, dissolves this in concentrated sulfuric acid, separates iron as iron sulfate, and hydrolyzes the solution to obtain a hydroxide precipitate. A production method in which rutile titanium oxide is taken out by baking at a high temperature. On the other hand, the chlorine method uses synthetic rutile or natural rutile as a raw material, reacts with chlorine gas and carbon at a high temperature of about 1000 ° C to synthesize titanium tetrachloride, and oxidizes this to extract rutile titanium oxide. Say. Among them, rutile-type titanium oxide produced by the chlorine method is particularly effective in suppressing the deterioration (yellowing) of the resin due to heat, and is more preferably used in the present invention.

Among these titanium oxides, it is particularly preferable to use titanium oxide whose surface is treated with hydrous alumina or aluminum hydroxide from the viewpoints of dispersibility in the composition, storage stability, and flame retardancy.
Moreover, it is preferable that the Y value is 70 or more, and, as for the cured coating film formed with the composition containing a titanium oxide, it is more preferable that it is 75 or more.

Black colorant:
As the black colorant, a known and commonly used black colorant can be used. Examples of black colorants include carbon black pigments such as CIPigmentblack 6, 7, 9 and 18; graphite pigments such as CIPigment black 8, 10; CIPigment black 11, 12 and 27; Pigment Brown 35, etc. Iron oxide pigments represented by: For example, KN-370 iron oxide manufactured by Toda Kogyo Co., Ltd., 13M titanium black manufactured by Mitsubishi Materials Corporation, anthraquinone pigments represented by CIPigment black 20, etc., CIPigment black 13, 25 and 29 Cobalt oxide pigments such as CIPigment black 15 and 28, copper oxide pigments such as CIPigment black 14 and 26, manganese pigments such as CIPigment black 14 and 26, and antimony oxide pigments such as CIPigment black 23 Pigments, nickel oxide pigments such as CIPigment black 30 etc., perylene pigments shown as CIPigment black 31 and 32, aniline pigments shown as Pigment Black 1, molybdenum sulfide and sulfur Bismuth can be exemplified as a preferable pigment. These pigments can be used alone or in appropriate combination. More preferable is carbon black. For example, carbon black manufactured by Mitsubishi Chemical Corporation, M-40, M-45, M-50, MA-8, MA-100, and perylene pigments are low among organic pigments. Effective for halogenation. Carbon black is more preferable because it is excellent in circuit concealment.

Examples of the red colorant include monoazo, diazo, azo lake, benzimidazolone, perylene, diketopyrrolopyrrole, condensed azo, anthraquinone, and quinacridone compounds.
Examples of blue colorants include metal-substituted or unsubstituted phthalocyanine-based and anthraquinone-based compounds.
Examples of the green colorant include metal-substituted or unsubstituted phthalocyanine-based, anthraquinone-based, and perylene-based compounds.
Examples of yellow colorants include monoazo, disazo, condensed azo, benzimidazolone, isoindolinone, and anthraquinone compounds.

  Specific examples of purple colorant, orange colorant, and brown colorant include Pigment Violet 19, 23, 29, 32, 36, 38, 42, Solvent Violet 13, 36, CIPigment Orange 1, 5, 13, 14, 16, 17, 24, 34, 36, 38, 40, 43, 46, 49, 51, 61, 63, 64, 71, 73, CIPigment Brown 23, 26, and the like.

  The blending amount of the colorant in the photosensitive resin composition of the present invention is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the (A) carboxyl group-containing resin. Part. In addition, when a colorant is white, the compounding quantity of a white colorant becomes like this. Preferably it is 50-300 mass parts with respect to 100 mass parts of (A) carboxyl group-containing resin, More preferably, it is 70-250 mass parts. (D) A coloring agent can be used individually by 1 type or in combination of 2 or more types.

[(E) Epoxy resin having two or more epoxy groups in one molecule]
The photosensitive resin composition of the present invention contains (E) an epoxy resin having two or more epoxy groups in one molecule. (E) As an epoxy resin having two or more epoxy groups in one molecule, epoxidized vegetable oil; bisphenol A type epoxy resin; hydroquinone type epoxy resin; bisphenol type epoxy resin; biphenyl type epoxy resin; thioether type epoxy resin; Brominated epoxy resin; novolac epoxy resin; biphenol novolac epoxy resin; bisphenol F epoxy resin; hydrogenated bisphenol A epoxy resin; glycidylamine epoxy resin; hydantoin epoxy resin; alicyclic epoxy resin; Methane type epoxy resin; bixylenol type or biphenol type epoxy resin or a mixture thereof; bisphenol S type epoxy resin; bisphenol A novolac type epoxy resin; Heteroethane epoxy resin; heterocyclic epoxy resin; diglycidyl phthalate resin; tetraglycidyl xylenoyl ethane resin; naphthalene group-containing epoxy resin; epoxy resin having dicyclopentadiene skeleton; glycidyl methacrylate copolymer epoxy resin; And glycidyl methacrylate copolymer epoxy resins; epoxy-modified polybutadiene rubber derivatives, CTBN-modified epoxy resins, and the like, but are not limited thereto. These epoxy resins can be used alone or in combination of two or more.

  (E) The compounding quantity of the epoxy resin which has 2 or more epoxy groups in 1 molecule becomes like this. Preferably it is 0.6-2.5 equivalent with respect to 1 equivalent of carboxyl groups of (A) carboxyl group-containing resin. Is in range. When it is 0.6 equivalent or more, the carboxyl group hardly remains in the cured product, and the heat resistance, alkali resistance, electrical insulation and the like are good. On the other hand, when the amount is 2.5 equivalents or less, the low molecular weight cyclic (thio) ether group hardly remains in the dry coating film, and the strength of the coating film is good. More preferably, it is 0.8-2.2 equivalent. Moreover, the photosensitive resin composition of this invention contains the thermosetting component other than the epoxy resin which has the 2 or more epoxy group in 1 molecule within the range which does not impair the effect of this invention. May be. Examples of other thermosetting components include amino resins, isocyanate compounds, blocked isocyanate compounds, maleimide compounds, benzoxazine compounds, oxazoline compounds, carbodiimide compounds, cyclocarbonate compounds, polyfunctional oxetane compounds, episulfide resins, and the like.

(Filler)
The photosensitive resin composition of the present invention can contain a filler as necessary in order to increase the physical strength of the coating film. As such a filler, a publicly known inorganic or organic filler can be used, and specifically, silica, talc, barium sulfate, hydrotalcite, aluminum hydroxide, magnesium hydroxide, boehmite, alumina, Neuburg silica, etc. Is mentioned. A filler can be used individually by 1 type or in combination of 2 or more types.

  The blending amount of the filler is preferably 300 parts by mass or less, more preferably 0.1 to 250 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin (A). When the compounding quantity of a filler is 300 mass parts or less, the viscosity of a photosensitive resin composition does not become high too much, printability is favorable, and hardened | cured material becomes difficult to become weak.

(Organic solvent)
In the photosensitive resin composition of the present invention, an organic solvent can be used for (A) synthesis of a carboxyl group-containing resin, adjustment of the composition, or adjustment of viscosity for application to a substrate or carrier film. . Examples of such organic solvents include ketones, aromatic hydrocarbons, glycol ethers, glycol ether acetates, esters, alcohols, aliphatic hydrocarbons, petroleum solvents, and the like. More specifically, ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene; cellosolve, methyl cellosolve, butyl cellosolve, carbitol, methyl carbitol, butyl carbitol, propylene glycol monomethyl Glycol ethers such as ether, dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, triethylene glycol monoethyl ether; ethyl acetate, butyl acetate, dipropylene glycol methyl ether acetate, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate , Esters such as propylene glycol butyl ether acetate; ethanol, propano , Ethylene glycol, alcohols such as propylene glycol; octane, aliphatic hydrocarbons decane; petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, petroleum solvents such as solvent naphtha or the like. Such an organic solvent can be used individually by 1 type or in combination of 2 or more types.

(Other optional ingredients)
If necessary, the photosensitive resin composition of the present invention further includes components such as a thermosetting catalyst, a urethanization catalyst, a thermoplastic resin, a block copolymer, an elastomer, an adhesion promoter, an antioxidant, and an ultraviolet absorber. Can be blended. As these, those known in the field of electronic materials can be used. Further, the photosensitive resin composition of the present invention includes known and commonly used thickeners such as finely divided silica, hydrotalcite, organic bentonite and montmorillonite, antifoaming agents such as silicone-based, fluorine-based and polymer-based and / or Known and commonly used additives such as leveling agents, imidazole-based, thiazole-based, triazole-based silane coupling agents, rust preventives and the like can be blended.

  The photosensitive resin composition of the present invention comprises at least a main component containing (A) a carboxyl group-containing resin, at least (C) a photocurable monomer, and (E) two or more epoxy groups in one molecule. It is preferably a two-component photosensitive resin composition comprising a curing agent containing an epoxy resin. The (B) photopolymerization initiator and the (D) colorant may be contained in either the main agent or the curing agent. Moreover, when it contains another component, it may be contained in either the main agent or the curing agent.

  The photosensitive resin composition of the present invention is useful for forming a pattern layer of a printed wiring board, and is particularly useful as a material for a solder resist or an interlayer insulating layer.

  The dry film of the present invention has a resin layer made of the photosensitive resin composition of the present invention. The dry film of the present invention is manufactured by coating the photosensitive resin composition of the present invention on a carrier film (support), drying, laminating a protective film as necessary, and forming a dry coating film. can do. When forming a dry film, the photosensitive resin composition of the present invention is diluted with the above organic solvent to adjust to an appropriate viscosity, and is applied to a comma coater, blade coater, lip coater, rod coater, squeeze coater, reverse coater, transfer roll coater. A film can be obtained by applying a uniform thickness on a carrier film with a gravure coater, spray coater or the like, and drying usually at a temperature of 50 to 130 ° C. for 1 to 30 minutes. Although there is no restriction | limiting in particular about a coating film thickness, Generally, it is 1-150 micrometers in the film thickness after drying, Preferably it selects suitably in the range of 10-60 micrometers.

  As the carrier film, a plastic film is used, and a plastic film such as a polyester film such as polyethylene terephthalate, a polyimide film, a polyamideimide film, a polypropylene film, or a polystyrene film is preferably used. Although there is no restriction | limiting in particular about the thickness of a carrier film, Generally, it selects suitably in the range of 10-150 micrometers.

  After the photosensitive resin composition of the present invention is formed on the carrier film, a peelable cover film may be laminated on the film surface for the purpose of preventing dust from adhering to the film surface. preferable. As the peelable cover film, 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 adhesive strength between the film and the carrier film is exceeded. What is necessary is just to have a smaller adhesive force between the membrane and the cover film.

  The photosensitive resin composition of the present invention is adjusted to a viscosity suitable for the coating method with, for example, the organic solvent, and on the substrate, a dip coating method, a flow coating method, a roll coating method, a bar coater method, a screen printing method, A tack-free coating film can be formed by applying the organic solvent contained in the composition at a temperature of about 60 to 100 ° C. by volatile drying (preliminary drying) at a temperature of about 60 to 100 ° C. In the case of a dry film obtained by applying the above composition on a carrier film and drying and winding it as a film, after laminating the photosensitive resin composition layer on the base material so as to come into contact with the base material The resin layer can be formed by peeling off the carrier film.

  Examples of the base material include printed circuit boards and flexible printed circuit boards in which circuits are formed in advance, paper phenol, paper epoxy, glass cloth epoxy, glass polyimide, glass cloth / non-woven cloth epoxy, glass cloth / paper epoxy, synthetic fiber. Copper graded laminates of all grades (FR-4 etc.) and other polyimides using materials such as epoxy, fluorine, polyethylene, polyphenylene ether, polyphenylene oxide, cyanate ester, etc. A film, a PET film, a glass substrate, a ceramic substrate, a wafer plate, etc. can be mentioned.

  Volatile drying performed after the photosensitive resin composition of the present invention is applied may be performed by using a hot air circulation drying furnace, an IR furnace, a hot plate, a convection oven or the like (using a steam-heated heat source in the dryer. Can be carried out by using a counter current contact method and a method of spraying a nozzle on a support.

  For example, the photosensitive resin composition of the present invention is heated to a temperature of about 140 to 180 ° C. to be thermally cured, whereby (A) the carboxyl group-containing resin and (E) two or more epoxies per molecule. The epoxy resin having a group reacts to form a cured coating film excellent in various properties such as heat resistance, chemical resistance, moisture absorption resistance, adhesion, and electrical characteristics.

  The exposed part (part irradiated with active energy rays) is applied to the coating film obtained after applying the photosensitive resin composition of the present invention and evaporating and drying the solvent (irradiation with active energy rays). ) Is cured. Further, by a contact method (or a non-contact method), exposure is selectively performed with an active energy ray through a photomask having a pattern formed thereon or direct pattern exposure is performed by a laser direct exposure machine, and an unexposed portion is diluted with a dilute alkaline aqueous solution (for example, 0.3 The resist pattern is formed by development with a 3 wt% sodium carbonate aqueous solution.

As an exposure machine used for the active energy ray irradiation, a high-pressure mercury lamp lamp, an ultra-high pressure mercury lamp lamp, a metal halide lamp, a mercury short arc lamp, and the like may be used as long as the apparatus irradiates ultraviolet rays in a range of 350 to 450 nm. Furthermore, a direct drawing apparatus (for example, a laser direct imaging apparatus that directly draws an image with a laser using CAD data from a computer) can also be used. The amount of exposure for image formation varies depending on the film thickness and the like, but is generally 100 to 1000 mJ / cm ² , preferably 200 to 800 mJ / cm ² .

  The developing method can be a dipping method, a shower method, a spray method, a brush method, etc., and as a developing solution, potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, Alkaline aqueous solutions such as ammonia and amines can be used.

  Hereinafter, the present invention will be specifically described with reference to Examples, Reference Examples and Comparative Examples, but the present invention is not limited to the following Examples. In the following, “part” and “%” are based on mass unless otherwise specified.

(Preparation of photosensitive resin composition)
The components shown in Table 1 below are divided into a main agent and a curing agent, blended in the proportions (parts by mass) shown in the table, premixed with a stirrer, and then kneaded with a three roll mill. Obtained. The obtained main agent and curing agent were mixed to prepare a photosensitive resin composition. It was 15 micrometers or less when the dispersion degree of each photosensitive resin composition obtained here was evaluated by the particle size measurement by the grind meter by an Erichsen company.

＊１：サイクロマーＰＡＣＡＺ２５０（固形分４５ｗｔ％の不飽和基含有カルボキシル基含有共重合樹脂溶液、ダイセル化学社製）
＊２：タイペークＣＲ−５８（ルチル型酸化チタン、石原産業社製）
＊３：カーボンＭＡ−１００（三菱化学社製）
＊４：硫酸バリウムＢ−３０（堺化学社製）
＊５：ＬＭＰ−１００（富士タルク工業社製）
＊６：ルシリンＴＰＯ（アシルフォスフィンオキサイド系光重合開始剤、ＢＡＳＦジャパン社製）
＊７：２，４−ジエチルチオキサントン（日本化薬社製）
＊８：シリコンＫＳ６６（信越化学工業社製）
＊９：ＹＸ８０３４（ビスフェノールＡ型の水添エポキシ樹脂、三菱化学社製）
＊１０：ＹＸ−４０００（ビフェニル型エポキシ樹脂、三菱化学社製）
＊１１：ジペンタエリスリトールペンタアクリレート
＊１２：ジペンタエリスリトールヘキサアクリレート
＊１３：ジプロピレングリコールモノメチルエーテル

* 1: Cyclomer PACAZ250 (unsaturated group-containing carboxyl group-containing copolymer resin solution having a solid content of 45 wt%, manufactured by Daicel Chemical Industries)
* 2: Taipei CR-58 (rutile titanium oxide, manufactured by Ishihara Sangyo Co., Ltd.)
* 3: Carbon MA-100 (Mitsubishi Chemical Corporation)
* 4: Barium sulfate B-30 (manufactured by Sakai Chemical Co., Ltd.)
* 5: LMP-100 (manufactured by Fuji Talc Industrial Co., Ltd.)
* 6: Lucillin TPO (acylphosphine oxide photopolymerization initiator, manufactured by BASF Japan)
* 7: 2,4-diethylthioxanthone (manufactured by Nippon Kayaku Co., Ltd.)
* 8: Silicon KS66 (manufactured by Shin-Etsu Chemical Co., Ltd.)
* 9: YX8034 (Bisphenol A type hydrogenated epoxy resin, manufactured by Mitsubishi Chemical Corporation)
* 10: YX-4000 (biphenyl type epoxy resin, manufactured by Mitsubishi Chemical Corporation)
* 11: Dipentaerythritol pentaacrylate * 12: Dipentaerythritol hexaacrylate * 13: Dipropylene glycol monomethyl ether

  Using the obtained main agent, curing agent and photosensitive resin composition, evaluation was performed as follows.

Resist performance evaluation:
<Sensitivity>
A copper-clad laminate with a copper thickness of 35 μm was polished with buffalo, washed with water and dried, and the photosensitive resin compositions of Examples 5 and 6, Reference Examples 1 to 4 and Comparative Examples 1 to 3 were applied by screen printing, and 80 It was dried for 30 minutes in a hot air circulation drying oven at 0 ° C. After drying, it was exposed at an exposure amount of 600 mJ / cm ² through a photomask (21 steps of step tablet) using an exposure machine equipped with a metal halide lamp manufactured by Oak Manufacturing Co., Ltd. The irradiated one was used as a test piece, and a 1% Na ₂ CO ₃ aqueous solution at 30 ° C. was developed for 90 seconds under the condition of a spray pressure of 0.2 MPa, and then the number of steps of the remaining coating film was visually determined. The evaluation results are shown in Table 2.

<Resolution>
A substrate on which a circuit pattern having a line / space of 30/30 to 100/100 μm was formed on a copper clad laminate having a copper thickness of 50 μm was washed with water after buffing and dried. The photosensitive resin compositions of Examples 5 and 6, Reference Examples 1 to 4 and Comparative Examples 1 to 3 were applied by screen printing on the pretreated substrate, and a hot air circulation drying oven at 80 ° C. For 30 minutes. After drying, exposure was performed at an exposure amount of 600 mJ / cm ² using a high-pressure mercury lamp exposure apparatus. As the exposure pattern, a pattern for drawing a 30/40/50/60/70/80/90/100 μm line in the space portion was used. After exposure, a 1% Na ₂ CO ₃ aqueous solution at 30 ° C. was developed for 90 seconds under the condition of a spray pressure of 0.2 MPa to form a pattern, and the width of the remaining minimum line was defined as resolution. The evaluation results are shown in Table 2.

Stability evaluation:
<Storage stability>
The main agent used in the preparation of the photosensitive resin compositions of Examples 5 and 6, Reference Examples 1 to 4 and Comparative Examples 1 to 3 was adjusted to a viscosity of 260 to 300 dPa · s and a TI value of 1.1 ± 0.1. The viscosity of the curing agent was adjusted to 80 to 90 dPa · s and a TI value of 1.6 ± 0.2. Thereafter, it was stored at 20 ° C. for 90 days, and the viscosity and TI value were measured. Viscosity and TI value were measured using an E-type viscometer manufactured by Tokyo Keiki Co., Ltd., and the viscosity (η ₅ , η ₅₀ ) was measured at 25 ° C. with a rotation speed of 5 rpm and 50 rpm, and η ₅ / η ₅₀ was determined as TI. Value. The evaluation results are shown in Table 2.

It turns out that the photosensitive resin composition of an Example is excellent in resolution and storage stability. On the other hand, Comparative Examples 1 to 3 in which the ratio of dipentaerythritol hexa (meth) acrylate is less than 60% by mass per total sum of dipentaerythritol hexa (meth) acrylate and dipentaerythritol penta (meth) acrylate are resolved. The storage stability of the curing agent was inferior.

Claims (4)

(A) a carboxyl group-containing resin, (B) a photopolymerization initiator, (C) a photocurable monomer, (D) a colorant, and (E) an epoxy resin having two or more epoxy groups in one molecule. A photosensitive resin composition containing,
The (C) photocurable monomer contains (C-1) dipentaerythritol hexa (meth) acrylate and (C-2) dipentaerythritol penta (meth) acrylate, and (C-1) The ratio of (C-1) per sum of (C-2) is 60% by mass or more,
The photosensitive resin composition for printed wiring boards, wherein the colorant (D) is carbon black. A dry film comprising a resin layer comprising the photosensitive resin composition for a printed wiring board according to claim 1. The cured product of the photosensitive resin composition for printed wiring boards of Claim 1, or the resin layer of the dry film of Claim 2.   A printed wiring board comprising the cured product according to claim 3.