JP6456313B2 - Photosensitive resin composition - Google Patents

Description

  The present invention relates to a photosensitive resin composition, particularly a photosensitive resin composition useful as an insulating film of a circuit board, and a printed wiring board having a cured film of the photosensitive resin composition.

  A printed wiring board is used to form a pattern of a conductor circuit on a substrate and to mount electronic components on the soldering land of the pattern by soldering, and the circuit portion excluding the soldering land is used as a permanent protective film. It is covered with a solder resist film. This prevents solder from adhering to unnecessary parts when soldering electronic components to a printed wiring board, and prevents circuit conductors from being directly exposed to air and being corroded by oxidation or humidity. To do.

  In recent years, photosensitive resin compositions that are applied as solder resist films have been required to have high resolution and high precision as the wiring density of printed wiring boards has become finer. A photographic development method that is excellent in coverage of parts is widely adopted. When forming a solder resist film by a photographic development method, for example, after coating the entire surface of a liquid composition that is a photosensitive resin composition on a printed wiring board, and volatilizing the solvent in the coating film, The coating film is exposed, and the unexposed portion is removed with an alkaline solution and developed.

  The applied cured coating film may be required to have excellent edge covering properties and coating properties, for example. Therefore, as a photosensitive resin composition, a carboxyl group-containing photosensitive resin, a silicon dioxide powder and / or metal oxide powder produced by a thermal decomposition method, a photopolymerization initiator, a diluent, an epoxy compound, A photosensitive resin composition containing titanium oxide has been proposed (Patent Document 1).

  On the other hand, the cured coating has a thermal shock resistance, that is, it can prevent cracks from occurring even if the cured coating is repeatedly exposed to a low temperature atmosphere and a high temperature atmosphere without impairing the solder heat resistance. May be required. Furthermore, there are cases where better coating properties are required.

JP 2011-133670 A

  In view of the above circumstances, an object of the present invention is to provide a photosensitive resin composition capable of obtaining a cured product excellent in thermal shock resistance and coating properties without impairing basic characteristics such as solder heat resistance and alkali developability. To provide things.

  Embodiments of the present invention include (A) a carboxyl group-containing photosensitive resin, (B) core-shell structured particles having a core containing a polysiloxane compound, (C) a photopolymerization initiator, and (D) a reactive diluent. And (E) an epoxy compound.

  In an embodiment of the present invention, the core-shell structure particles having a core containing the (B) polysiloxane compound contain 10 to 40 parts by mass with respect to 100 parts by mass of the (A) carboxyl group-containing photosensitive resin. It is the photosensitive resin composition characterized by the above-mentioned.

  The aspect of the present invention is the core-shell structure particle having the core containing (B) the polysiloxane compound dispersed in the epoxy compound (E), wherein the (B) core-shell structure particle containing the polysiloxane compound is used. It is the photosensitive resin composition characterized by these.

  In the said aspect, it becomes the aspect by which the particle | grains of the core shell structure which have a core containing the (B) polysiloxane compound which is a raw material are previously disperse | distributed in the (E) epoxy compound. That is, in the above embodiment, a premix is used in which (B) particles having a core-shell structure having a core containing a polysiloxane compound are premixed with (E) an epoxy compound.

  An aspect of the present invention is the photosensitive resin composition, wherein the shell of the particle of the core-shell structure having a core containing the polysiloxane compound (B) is an acrylic resin and / or a methacrylic resin. .

  An aspect of the present invention is a printed wiring board having a cured film of the photosensitive resin composition.

  According to an aspect of the present invention, by including particles of a core-shell structure having a core containing a polysiloxane compound, without impairing basic properties such as solder heat resistance and alkali developability, thermal shock resistance and coating properties It is possible to obtain an excellent cured product.

  According to the aspect of the present invention, (B) particles having a core-shell structure having a core containing a polysiloxane compound are contained in an amount of 10 to 40 parts by mass with respect to 100 parts by mass of (A) a carboxyl group-containing photosensitive resin. As a result, the thermal shock resistance can be further improved.

  According to an aspect of the present invention, (B) core-shell structured particles having a core containing a polysiloxane compound are dispersed in (E) an epoxy compound. (B) core-shell structured particles having a core containing a polysiloxane compound. As a result, in the cured product of the photosensitive resin composition, the particles of the core-shell structure having the core containing the polysiloxane compound are more uniformly dispersed, and the thermal shock resistance and the coating property are further improved. be able to.

  Next, the photosensitive resin composition of the present invention will be described below. The photosensitive resin composition of the present invention comprises (A) a carboxyl group-containing photosensitive resin, (B) particles having a core-shell structure having a core containing a polysiloxane compound, (C) a photopolymerization initiator, and (D). It contains a reactive diluent and (E) an epoxy compound.

(A) Carboxyl group-containing photosensitive resin The carboxyl group-containing photosensitive resin is not particularly limited, and examples thereof include a resin having one or more photosensitive unsaturated double bonds. As a carboxyl group-containing photosensitive resin, for example, at least part of the epoxy group of a polyfunctional epoxy resin having two or more epoxy groups in one molecule, acrylic acid or methacrylic acid (hereinafter referred to as “(meth) acrylic acid”) A radical polymerizable unsaturated monocarboxylic acid such as epoxy (meth) acrylate to obtain a radical polymerizable unsaturated monocarboxylic oxide epoxy resin, and a polybasic acid or its Mention may be made of polybasic acid-modified radically polymerizable unsaturated monocarboxylic oxide epoxy resins such as polybasic acid-modified epoxy (meth) acrylates obtained by reacting anhydrides.

  Any polyfunctional epoxy resin can be used as long as it is a bifunctional or higher functional epoxy resin. Although the epoxy equivalent of a polyfunctional epoxy resin is not specifically limited, 1000 or less are preferable and 100-500 are especially preferable. Examples of the polyfunctional epoxy resin include biphenyl type epoxy resin, naphthalene type epoxy resin, dicyclopentadiene type epoxy resin, rubber modified epoxy resin such as silicone modified epoxy resin, ε-caprolactone modified epoxy resin, bisphenol A type, bisphenol. Phenol type novolak type epoxy resin such as F type, bisphenol AD type, cresol novolak type epoxy resin such as о-cresol novolak type, bisphenol A novolak type epoxy resin, cyclic aliphatic polyfunctional epoxy resin, glycidyl ester type polyfunctional epoxy resin, Glycidylamine type polyfunctional epoxy resin, heterocyclic polyfunctional epoxy resin, bisphenol modified novolac type epoxy resin, polyfunctional modified novolak type epoxy resin, phenols and phenolic hydroxyl group Examples thereof include condensate type epoxy resins with aromatic aldehydes. Moreover, you may use what introduce | transduced halogen atoms, such as Br and Cl, into these resin. These epoxy resins may be used alone or in combination of two or more.

  The radically polymerizable unsaturated monocarboxylic acid is not particularly limited, and examples thereof include acrylic acid, methacrylic acid, crotonic acid, cinnamic acid, and acrylic acid and methacrylic acid are preferable. These radically polymerizable unsaturated monocarboxylic acids may be used alone or in combination of two or more.

  It is not specifically limited to the reaction method of an epoxy resin and radically polymerizable unsaturated monocarboxylic acid, For example, it can be made to react by heating an epoxy resin and radically polymerizable unsaturated monocarboxylic acid in a suitable diluent. it can.

  The polybasic acid or polybasic acid anhydride is for reacting with a hydroxyl group produced by the reaction between the epoxy resin and the radically polymerizable unsaturated monocarboxylic acid to introduce a free carboxyl group into the resin. The polybasic acid or its anhydride is not particularly limited, and either saturated or unsaturated can be used. Polybasic acids include, for example, succinic acid, maleic acid, adipic acid, citric acid, phthalic acid, tetrahydrophthalic acid, 3-methyltetrahydrophthalic acid, 4-methyltetrahydrophthalic acid, 3-ethyltetrahydrophthalic acid, 4- Ethyltetrahydrophthalic acid, hexahydrophthalic acid, 3-methylhexahydrophthalic acid, 4-methylhexahydrophthalic acid, 3-ethylhexahydrophthalic acid, 4-ethylhexahydrophthalic acid, methyltetrahydrophthalic acid, methylhexahydro Examples include phthalic acid, endomethylenetetrahydrophthalic acid, methylendomethylenetetrahydrophthalic acid, trimellitic acid, pyromellitic acid, and diglycolic acid. Examples of polybasic acid anhydrides include these anhydrides. These compounds may be used alone or in combination of two or more.

  In the present invention, the polybasic acid-modified unsaturated monocarboxylic oxide epoxy resin can also be used as a carboxyl group-containing photosensitive resin. Carboxyl group-containing photosensitivity in which radically polymerizable unsaturated groups are further introduced by reacting a glycidyl compound having one or more radically polymerizable unsaturated groups and an epoxy group, thereby further improving photosensitivity. It is good also as resin.

  In this carboxyl group-containing photosensitive resin with improved photosensitivity, the radical polymerizable unsaturated group is bonded to the side chain of the polybasic acid-modified unsaturated monocarboxylic oxide epoxy resin skeleton by the reaction of the glycidyl compound. The photopolymerization reactivity is high, and the photosensitive property can be excellent. Examples of the compound having one or more radically polymerizable unsaturated groups and an epoxy group include glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether, pentaerythritol triacrylate monoglycidyl ether, pentaerythritol trimethacrylate monoglycidyl ether, and the like. Can be mentioned. In addition, you may have multiple glycidyl groups in 1 molecule. The above-mentioned compound having one or more radically polymerizable unsaturated groups and an epoxy group may be used alone or in combination of two or more.

  The acid value of the carboxyl group-containing photosensitive resin is not particularly limited, but the lower limit is preferably 30 mg KOH / g, particularly preferably 40 mg KOH / g, from the viewpoint of reliable alkali development. On the other hand, the upper limit of the acid value is preferably 200 mgKOH / g from the viewpoint of preventing dissolution of the exposed area with an alkali developer, and particularly preferably 150 mgKOH / g from the viewpoint of preventing moisture from being cured and preventing deterioration of electrical characteristics.

  Further, the mass average molecular weight of the carboxyl group-containing photosensitive resin is not particularly limited, but the lower limit is preferably 3000 and particularly preferably 5000 from the viewpoint of toughness of the cured product and dryness to touch. On the other hand, the upper limit value of the mass average molecular weight is preferably 200000, particularly preferably 50000, from the viewpoint of smooth alkali developability.

  The carboxyl group-containing photosensitive resin may be synthesized in the reaction step using the above raw materials, or a commercially available carboxyl group-containing photosensitive resin may be used. Examples of carboxyl group-containing photosensitive resins that have been marketed include “SP-4621” (manufactured by Showa Denko KK), “ZAR-2000”, “ZFR-1122”, “FLX-2089” (above, Japan). Kayaku Co., Ltd.), “Cyclomer P (ACA) Z-250” (manufactured by Daicel Ornex Co., Ltd.), and the like. These resins may be used alone or in combination of two or more.

(B) Core-shell structure particles having a core containing a polysiloxane compound By blending core-shell structure particles having a core containing a polysiloxane compound (hereinafter sometimes referred to as “core-shell structure particles”), solder heat resistance A cured product having a good balance between thermal shock resistance and coating property can be obtained without impairing basic properties such as the property and alkali developability.

  The core-shell structured particle is a particle having a structure in which a part or all of the surface of a particle serving as a nucleus (core) is covered with a film (shell). The core-shell structure particles are not particularly limited as long as the core material contains a polysiloxane compound. Examples of the film material include acrylic resins that are polymers containing acrylic acid and / or acrylic esters, methacrylic resins that are polymers containing methacrylic acid and / or methacrylic esters, and aromatic vinyl compounds. Polymer of vinyl cyanide compound, polymer of acrylamide derivative, polymer of maleimide derivative, and the like. Of these, acrylic resins and methacrylic resins are preferred because they are excellent in uniform dispersibility with respect to the epoxy compound.

  In the case of a premixed mixture in which the core-shell structured particles are premixed with an epoxy compound (for example, a liquid epoxy resin) described later, the shell may be a polymer having an affinity for the epoxy compound, for example, The resin and the polymer can be mentioned. In addition, the polysiloxane compound which is a material of the core is a rubber-like elastic body (elastomer).

  The shape of the core-shell structured particles is not particularly limited, but is preferably spherical from the viewpoint of uniform dispersibility with respect to the epoxy compound. The average primary particle diameter of the core-shell structured particles is not particularly limited, but the lower limit is preferably 10 nm, more preferably 50 nm, and particularly preferably 100 nm from the viewpoint of improving the dispersibility as the primary particles. On the other hand, the upper limit of the average primary particle diameter is preferably 1000 nm, more preferably 750 nm, and particularly preferably 500 nm from the viewpoint of the smoothness of the coating film. The “average particle size” means a particle size of 50 volume% from the small diameter side of the particle size distribution in the volume-based cumulative distribution when the particle size distribution is measured with a laser type particle size measuring device.

  The content of the core-shell structured particles is not particularly limited. For example, for 100 parts by mass of a carboxyl group-containing photosensitive resin (solid content, hereinafter the same), the lower limit value is a balance between thermal shock resistance and coating property. 3.0 parts by mass is preferable from the viewpoint of improving well, and 5.0 parts by mass is more preferable from the point of obtaining better thermal shock resistance and coating properties, and more excellent thermal shock resistance and coating properties. From the point of obtaining, 10 parts by mass is particularly preferable. On the other hand, the upper limit of the content of the core-shell structure particles with respect to 100 parts by mass of the carboxyl group-containing photosensitive resin is preferably 50 parts by mass from the viewpoint of the smoothness of the coating film, and more excellent thermal shock resistance and coating properties. 40 parts by mass is more preferable from the viewpoint of preventing the solder heat resistance from being lowered, and 20 from the viewpoint of reliably preventing the solder heat resistance from being reduced while obtaining better thermal shock resistance and coating properties. Part by mass is particularly preferred.

(C) Photopolymerization initiator The photopolymerization initiator is not particularly limited as long as it is generally used. For example, etanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H- Carbazol-3-yl] -1- (0-acetyloxime), phenylbis (2,4,6-trimethylbenzoyl) phosphine oxide, 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-methyl-4 '-(methylthio) -2-morpholinopropiophenone 2-hydroxy-2-methyl-1 -Phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 4- (2-hydroxyethoxy) phenyl-2- (hydroxy-2-propyl) ketone, benzophenone, p-phenylbenzophenone, 4,4'-diethylaminobenzophenone , Dichlorobenzophenone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tertiarybutylanthraquinone, 2-aminoanthraquinone, 2-methylthioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2, , 4-diethylthioxanthone, benzyldimethyl ketal, acetophenone dimethyl ketal, P-dimethylaminobenzoic acid ethyl ester, and the like. These may be used alone or in combination of two or more.

  Although content of a photoinitiator is not specifically limited, 5-30 mass parts is preferable with respect to 100 mass parts of carboxyl group-containing photosensitive resin, and 7-20 mass parts is especially preferable.

(D) Reactive Diluent A reactive diluent is, for example, a photopolymerizable monomer and is a compound having at least one polymerizable double bond per molecule, preferably at least two polymerizable double bonds per molecule. The reactive diluent is used to obtain a cured product having sufficient acid resistance, heat resistance, alkali resistance, etc., by sufficiently photocuring the photosensitive resin composition.

  The reactive diluent is not particularly limited as long as it is the above compound. For example, 2-hydroxyethyl methacrylate, phenoxyethyl methacrylate, diethylene glycol monomethacrylate, 2-hydroxy-3-phenoxypropyl acrylate, 1,4- Butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, neopentyl glycol adipate di (meth) acrylate, hydroxypivalate neo Pentyl glycol di (meth) acrylate, dicyclopentanyl di (meth) acrylate, caprolactone modified dicyclopentenyl di (meth) acrylate, ethylene oxide modified di (meth) acrylate Rate, allylated cyclohexyl di (meth) acrylate, isocyanurate di (meth) acrylate, trimethylolpropane tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, dipentaerythritol tri (meth) acrylate, dipentaerythritol tri (Meth) acrylate, pentaerythritol tri (meth) acrylate, propylene oxide modified trimethylolpropane tri (meth) acrylate, tris (acryloxyethyl) isocyanurate, propionic acid modified dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (Meth) acrylate, caprolactone-modified dipentaerythritol hexa (meth) acrylate, urethane (meth) acrylate Etc. The. These may be used alone or in combination of two or more.

  Content of a reactive diluent is not specifically limited, For example, 2.0-500 mass parts is preferable with respect to 100 mass parts of carboxyl group-containing photosensitive resin, and 10-300 mass parts is especially preferable.

(E) Epoxy compound An epoxy compound is for obtaining the cured coating film of sufficient intensity | strength by raising the crosslinking density of a cured coating film, for example, can mention an epoxy resin. Examples of the epoxy resin include biphenyl type epoxy resin, bisphenol A type epoxy resin, novolak type epoxy resin (phenol novolak type epoxy resin, o-cresol novolak type epoxy resin, p-tert-butylphenol novolak type, etc.), bisphenol F, and the like. Bisphenol F-type and bisphenol S-type epoxy resins obtained by reacting bisphenol S with epichlorohydrin, alicyclic epoxy resins having cyclohexene oxide groups, tricyclodecane oxide groups, cyclopentene oxide groups, and the like, tris (2,3- Epoxypropyl) isocyanurate, triglycidyl isocyanurate having a triazine ring such as triglycidyltris (2-hydroxyethyl) isocyanurate, dicyclopentadi Emission type epoxy resins, adamantane type epoxy resin. These compounds may be used alone or in combination of two or more.

  Although content of an epoxy compound is not specifically limited, 5.0-60 mass parts is preferable from the point which obtains a coating film with sufficient intensity | strength after hardening with respect to 100 mass parts of carboxyl group-containing photosensitive resin, 0-50 mass parts is especially preferable.

  In the photosensitive resin composition of the present invention, in addition to the components (A) to (E) described above, various components such as a block copolymer, a filler, a colorant, and various additives are added as necessary. A non-reactive diluent or the like can be contained.

  The block copolymer contributes to further improving thermal shock resistance and solder heat resistance. Examples of the block copolymer include a triblock copolymer and a diblock copolymer.

Examples of the triblock copolymer include a block copolymer having a [a ¹ ]-[b ¹ ]-[a ² ] structure. The polymer block of [a ¹ ] has a glass transition temperature higher than that of the polymer block of [b ¹ ], and thus has a relatively hard block structure. The glass transition temperature of [a ¹ ] is preferably 60 ° C. or higher and particularly preferably 90 ° C. or higher from the viewpoint of solder heat resistance. Examples of the polymer block [a ¹ ] include polymethyl acrylate, polymethyl methacrylate, and polystyrene. Similarly to the polymer block of [a ¹ ], the polymer block of [a ² ] has a glass transition temperature higher than that of the polymer block of [b ¹ ], and thus has a relatively hard block structure. The glass transition temperature of ^{[a 2],} as with ^{[a 1],} preferably 60 ° C. or higher from the viewpoint of soldering heat resistance, particularly preferably at least 90 ° C.. Examples of the polymer block of [a ² ] include polymethyl acrylate, polymethyl methacrylate, polystyrene and the like, as in the polymer block of [a ¹ ]. The glass transition temperature can be measured by differential scanning calorimetry.

The polymer block of [b ¹ ] has a glass transition temperature lower than that of the polymer block of [a ¹ ] and the polymer block of [a ² ], and thus has a relatively soft block structure. The glass transition temperature of [b ¹ ] is preferably −20 ° C. or less, and preferably −30 ° C. or less from the viewpoint of preventing the cured product from cracking even when subjected to thermal shock by imparting flexibility to the cured product. Is particularly preferred. Examples of the polymer block [b ¹ ] include poly n-butyl acrylate, poly n-butyl methacrylate, polybutadiene, and polyisoprene.

The content of [b ¹ ] in the triblock copolymer is not particularly limited, and is preferably 20 to 65% by mass from the viewpoint of contributing to thermal shock resistance while improving solder heat resistance, for example. 40-55 mass% is especially preferable from the point which improves more. Further, the mass average molecular weight of the triblock copolymer is not particularly limited. For example, the lower limit is preferably 10,000 from the viewpoint of tackiness, and particularly preferably 20,000 from the viewpoint of flexibility. On the other hand, the upper limit is preferably 200,000, particularly preferably 100,000, from the viewpoint of developability.

In addition, the triblock copolymer includes, for example, a monomer constituting the block copolymer having the [a ¹ ]-[b ¹ ]-[a ² ] structure described above and a hydrophilic group (for example, a hydroxyl group, Triblock copolymer, which is obtained by copolymerizing monomer materials such as carboxyl group, amino group, etc. (for example, hydroxyethyl (meth) acrylate, (meth) acrylic acid, etc.) and dimethyl (meth) acrylamide. It may be a coalescence.

Examples of the diblock copolymer include a block copolymer having a [a ³ ]-[b ² ] structure. Here, the polymer block of [a ³ ] has a glass transition temperature higher than that of the polymer block of [b ² ], and thus has a relatively hard block structure. The glass transition temperature of [a ³ ] is preferably 60 ° C. or higher, particularly preferably 90 ° C. or higher, from the viewpoint of solder heat resistance. The polymer block [a ^3], for example, polymer blocks of the above [a ^1], as in the polymer block [a ^2], polymethyl acrylate, polymethyl methacrylate, polystyrene, and the like.

The polymer block of [b ² ] has a glass transition temperature lower than that of the polymer block of [a ³ ], and thus has a relatively soft block structure. The glass transition temperature of [b ² ] is preferably −20 ° C. or less, and particularly preferably −30 ° C. or less from the viewpoint of preventing generation of cracks even when subjected to thermal shock by imparting flexibility to the cured product. Examples of the polymer block of [b ² ] include poly n-butyl acrylate, poly n-butyl methacrylate, polybutadiene, polyisoprene and the like, similarly to the polymer block of [b ¹ ] described above.

The content of [b ² ] in the diblock copolymer is not particularly limited, and is preferably 20 to 65% by mass, for example, from the viewpoint of improving the solder heat resistance and the thermal shock resistance in a more balanced manner. 40-55 mass% is especially preferable from the point which improves solder heat resistance, acquiring resistance. Moreover, the mass average molecular weight of the diblock copolymer is not particularly limited. For example, the lower limit is preferably 10,000 from the viewpoint of tackiness, and particularly preferably 20,000 from the viewpoint of flexibility. On the other hand, the upper limit is preferably 200,000, particularly preferably 100,000, from the viewpoint of developability.

  The content of the block copolymer is not particularly limited. For example, the lower limit is preferably 2.0 parts by mass from the viewpoint of further improving the solder heat resistance with respect to 100 parts by mass of the carboxyl group-containing photosensitive resin. 3.0 parts by mass is particularly preferable from the viewpoint of improving solder heat resistance and thermal shock resistance in a well-balanced manner. On the other hand, the upper limit is preferably 40 parts by mass from the viewpoint of alkali developability, and particularly preferably 30 parts by mass from the viewpoint of solder heat resistance.

  The filler is for increasing the physical strength of the coating film of the photosensitive resin composition, and examples thereof include talc, barium sulfate, hydrophobic silica, alumina, aluminum hydroxide, and mica.

  The colorant is not particularly limited, for example, titanium oxide which is a white colorant, phthalocyanine-based, anthraquinone-based, and azo-based organic pigments such as phthalocyanine green and phthalocyanine blue, and black pigments other than white Mention may be made of inorganic pigments such as carbon black which are colorants.

  The various additives include, for example, silicone-based, hydrocarbon-based, acrylic-based antifoaming agents, silane-based, titanate-based, alumina-based coupling agents, boron trifluoride-amine complex, dicyandiamide (DICY), and the like. Derivatives thereof, organic acid hydrazide, diaminomaleonitrile (DAMN) and its derivatives, guanamine and its derivatives, melamine and its derivatives, amine imide (AI) and latent curing agents such as polyamines, acetyl acetonate Zn and acetyl acetonate Cr, etc. Metal salts of acetylacetone, enamines, tin octylates, quaternary sulfonium salts, imidazoles such as triphenylphosphine and 2-mercaptobenzimidazole, imidazolium salts and thermosetting accelerators such as triethanolamine borate, polycarboxylic acids A And the like can be mentioned thixotropic agent such as Ido.

  The non-reactive diluent is for adjusting the drying property of the photosensitive resin composition, and examples thereof include a solvent. Examples of the solvent include ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene; methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, Glycol ethers such as diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, dipropylene glycol monoethyl ether, triethylene glycol monoethyl ether; ethyl acetate, butyl acetate, cellosolve acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, propylene glycol Monomethyl ether acetate and glyco Esters such as esters of ethers; ethanol, can be mentioned propanol, ethylene glycol, and alcohols such as propylene glycol.

  The manufacturing method of the above-described photosensitive resin composition of the present invention is not limited to a specific method. For example, the above-described components may be mixed and dispersed with a three roll at room temperature after being blended at a predetermined ratio. it can. Moreover, you may pre-mix with a stirrer before the said mixing dispersion | distribution as needed.

  Next, the example of the usage method of the photosensitive resin composition of this invention is demonstrated. Here, the method of applying the photosensitive resin composition of the present invention to a printed wiring board to form an insulating film such as a solder resist film will be described as an example.

  The photosensitive resin composition of the present invention obtained as described above, for example, on a circuit board such as a printed wiring board or a flexible printed wiring board having a circuit pattern formed by etching a copper foil, screen printing, Using a known coating method such as a spray coater, a bar coater, an applicator, a blade coater, a knife coater, a roll coater, or a gravure coater, a desired thickness, for example, a DRY film thickness of 20 to 40 μm is applied. After application, when a solvent is contained in the photosensitive resin composition of the present invention, in order to volatilize the solvent, pre-drying is performed at a temperature of about 60 to 80 ° C. for about 15 to 60 minutes for tacking. Form a free coating.

  Next, the negative film which has the pattern which made translucent except the land of a circuit pattern was stuck on the apply | coated photosensitive resin composition, and an ultraviolet-ray (for example, the range of wavelength 300-400 nm) is irradiated from it. . Then, the coating film is developed by removing the non-exposed areas corresponding to the lands with a dilute alkaline aqueous solution. As the developing method, a spray method, a shower method, or the like is used, and examples of the diluted alkaline aqueous solution used include 0.5 to 5% by mass of an aqueous sodium carbonate solution. Next, an insulating coating such as a desired solder resist film is formed on a circuit board such as a printed wiring board or a flexible printed wiring board by performing post-cure for 20 to 80 minutes with a hot air circulation dryer at 130 to 170 ° C. Can be formed.

  Next, examples of the present invention will be described. However, the present invention is not limited to these examples as long as the gist thereof is not exceeded.

Examples 1-5, Comparative Examples 1-6
Each component shown in the following Table 1 is blended in the blending ratio shown in the following Table 1, mixed and dispersed at room temperature using three rolls, and used in Examples 1 to 5 and Comparative Examples 1 to 6. A functional resin composition was prepared. And the prepared photosensitive resin composition was applied as follows and the test piece was produced. The numbers in Table 1 below indicate parts by mass. Moreover, the blank in Table 1 below means no blending.

  The details of each component in Table 1 are as follows.

(A) Carboxyl group-containing photosensitive resin Synthetic resin A was synthesized as follows.
In 250 parts by mass of diethylene glycol monoethyl ether acetate, 220 parts by mass of cresol novolac-type epoxy resin (manufactured by Sumitomo Chemical Co., Ltd., ESCN-220, epoxy equivalent 220) and 64.8 parts by mass of acrylic acid are dissolved and refluxed. Reaction was performed to obtain a cresol novolac type epoxy acrylate. Next, 123.2 parts by mass of hexahydrophthalic anhydride was added to the obtained cresol novolac type epoxy acrylate and reacted under reflux until the acid value reached the theoretical value, and then pentaerythritol triacrylate monoglycidyl ether 57.6. The synthetic resin A which is a carboxyl group-containing photosensitive resin having a solid content of 65% by mass was obtained by adding mass parts and further reacting.

(B) Core-shell structure particles having a core containing a polysiloxane compound. Kaneace MX-960: manufactured by Kaneka Corporation. In addition, the compounding quantity of Table 1 means the compounding quantity of particle | grains of core-shell structure itself.
GENIOPERL P52: powder, manufactured by Asahi Kasei Wacker Silicone.

Particles having a core-shell structure in which the core does not contain a polysiloxane compound, Kaneace MX-153: manufactured by Kaneka Corporation. In addition, the compounding quantity of Table 1 means the compounding quantity of particle | grains of core-shell structure itself.
-Kureha BTA751: Powder, manufactured by Kureha Chemical Co., Ltd.
-Staphyloid AC3871: Powder, manufactured by Ganz Kasei Co., Ltd.

(C) Photopolymerization initiator, Irgacure 907, Irgacure 819, Irgacure OXE-02: manufactured by Ciba Specialty Chemicals.
-KAYACURE JETX: manufactured by Nippon Kayaku Co., Ltd.

(D) Reactive diluent, EBECRYL8402: manufactured by Daicel Ornex.

(E) Epoxy compound / Epicoat 828, YX-4000: manufactured by Mitsubishi Chemical Corporation.

Block copolymer M52N: Polymethylmethacrylate-polybutylacrylate-dimethylacrylamide triblock copolymer copolymerized with dimethylacrylamide, and triblock copolymer copolymerized with dimethylacrylamide The polymerization ratio of dimethylacrylamide is 10 to 15% by mass (raw material conversion), mass average molecular weight 15000, manufactured by Arkema Co.

M52N is represented by the following formula [a ¹ ]-[b ¹ ]-[a ² ].
(In the formula, [a ¹ ] is a polymethyl methacrylate modified with N, N-dimethylacrylamide, and [a ² ] is a polymer block of polymethyl methacrylate modified with N, N-dimethylacrylamide.] b ¹ ] is a polymer block which is poly n-butyl acrylate not modified with N, N-dimethyl (meth) acrylamide, etc. The sum of the masses of [a ¹ ] and [a ² ] / [b ¹ ] The glass transition temperature is 135 ° C. (differential scanning calorimetry (DSC method)).

Filler barium sulfate B-34: manufactured by Sakai Chemical Industry Co., Ltd.
-LMS200: manufactured by Fuji Talc Co., Ltd.
-Leolo Seal DM-20S: manufactured by Tokuyama Corporation.
Colorant, Fast Gen Green: manufactured by DIC.
Additives and powdered melamine: manufactured by Nissan Chemical Industries, Ltd.
・ Antage MB: manufactured by Kawaguchi Chemical Industry Co., Ltd.
-DICY-7: manufactured by Japan Epoxy Resin Co., Ltd.
-KS-66: manufactured by Shin-Etsu Chemical Co., Ltd.
Non-reactive diluent / EDGAC: manufactured by Sanyo Chemicals Co., Ltd.

Test piece production process board: Printed wiring board (glass epoxy board “FR-4”, plate thickness 1.6 mm, conductor (Cu foil) thickness 50 μm)
Substrate surface treatment: buffing coating: screen printing (printing plate T120N), wet film thickness 35 μm
DRY film thickness: 20 μm
Pre-drying: 80 ° C., 20 minutes Exposure: 300 mJ / cm ² on the photosensitive resin composition (“HMW-680GW” manufactured by Oak Co.)
Alkali development: 1% by weight Na ₂ CO ₃ aqueous solution, liquid temperature 30 ° C., spray pressure 0.2 MPa, development time 60 seconds Post cure: 150 ° C., 60 minutes

The evaluation items are as follows.
(1) Thermal shock resistance test About the test piece produced in the above-mentioned test piece production process, with a thermal shock tester (manufactured by Hitachi Appliances, Ltd., Hitachi heat shock test device “ES-76LMS”), −65 ° C. / A test of 1500 cycles was performed with 30 minutes to 125 ° C./30 minutes as one cycle. Then, the coating film of the printed wiring board was observed with a microscope (x200), and the crack generation rate of the coating film was evaluated according to the following criteria. In addition, the observation position of a coating film is each corner | angular part of the 56 opening part of the coating film alkali-developed by the square shape (2.4 mm square) so that the circumference | surroundings of the exposed Cu foil (2.0 mm square pad) may be enclosed (Total of 224 locations).
5: Crack generation rate is 10% or less 4: Crack generation rate is over 10% to 20%
3: Crack generation rate exceeds 20% to 30%
2: Crack generation rate exceeds 30% to 50%
1: Crack generation rate exceeds 50%

(2) Solder heat resistance A flux (manufactured by Tamura Seisakusho, "ULF-210R") was applied to the test piece prepared in the test piece preparation step, and then dried at 25 ° C. Thereafter, the coated surface was directed downward, immersed in a solder bath at 260 to 262 ° C., and heated for 10 seconds. Thereafter, the test piece was taken out from the solder bath and cooled to room temperature. After cooling, the flux residue was wiped off with IPA, and the coating state after repeating the peeling test (peeling test) with a cellophane adhesive tape 1 to 3 times was visually observed and evaluated according to the following criteria.
○: No change is observed in the coating film even after 3 cycles are repeated. Δ: A change is observed in the coating film after 2 to 3 cycles are repeated.

(3) Coating property After the preliminary drying in the test piece preparation step, the coating film surface was visually evaluated according to the following criteria.
○: The coating film surface is smooth and there are no voids between the conductors △: The coating film surface is slightly distorted skin-like, but there are no voids between the conductors ×: The coating-film surface is distorted skin-like, and there are voids between the conductors Seen

(4) Alkali developability After the photosensitive resin composition prepared as described above is applied to the printed wiring board used in the test piece preparation step by a screen printing method, 40, 50, 60 at 80 ° C. Pre-dried for minutes. Thereafter, the test piece was taken out from the preliminary drying furnace, developed under the alkali development conditions in the test piece preparation step, the removal state of the coated film after development was visually observed, and evaluated according to the following criteria.
○: The coating film is completely removed even after the preliminary drying time of 60 minutes. Δ: The coating film is completely removed after the preliminary drying time of 40 minutes, but the coating film remains slightly after 50 minutes or 60 minutes. : The coating film remains with a predrying time of 40 minutes.

  The results of the evaluation are shown in Table 2 below.

  As shown in Table 2 above, by blending core-shell structured particles containing a polysiloxane compound as the core material, thermal shock resistance and coating properties are maintained without impairing basic properties such as solder heat resistance and alkali developability. And an excellent cured product could be obtained. Examples 2 and 5 in which about 14 parts by mass of core-shell structured particles having a core containing a polysiloxane compound are blended with 100 parts by mass (solid content) of a carboxyl group-containing photosensitive resin. The thermal shock resistance is further improved as compared with Examples 1 and 4 in which about 3.5 parts by mass of core-shell structured particles having a core are contained, and Example 2 is further coated as compared with Example 1. Also improved. In addition, Example 2 is a superior solder compared to Example 3 in which about 28 parts by mass of core-shell structured particles having a core containing a polysiloxane compound is added to 100 parts by mass of the carboxyl group-containing photosensitive resin. Heat resistance was obtained.

  Further, when the premixed product (Examples 1 and 2) in which the core-shell structure particles are premixed with the liquid epoxy resin is used from Examples 1 and 2 and Examples 4 and 5, the core-shell structure particles are liquid. Thermal shock resistance was further improved as compared with the case of using powders (Examples 4 and 5) that were not premixed in the epoxy resin.

  On the other hand, in a comparative example in which particles having a core-shell structure not containing a polysiloxane compound as a core material were blended, a cured product excellent in both thermal shock resistance and coating property could not be obtained.

  Since the photosensitive resin composition of the present invention can obtain a cured product excellent in thermal shock resistance and coatability without impairing properties such as solder heat resistance and alkali developability, for example, a printed wiring board. High utility value in the field.

Claims (7)

(A) a carboxyl group-containing photosensitive resin, (B) core-shell structured particles having a core containing a polysiloxane compound, (C) a photopolymerization initiator, (D) a reactive diluent, and (E) an epoxy. Containing a compound and a block copolymer ,
The (A) carboxyl group-containing photosensitive resin reacts with at least a part of the epoxy group of a polyfunctional epoxy resin having two or more epoxy groups in one molecule to react with a radical polymerizable unsaturated monocarboxylic acid to perform radical polymerization. A polybasic acid-modified radical-polymerizable unsaturated compound obtained by reacting a polybasic acid or its anhydride with the hydroxyl group produced by the radical-polymerizable unsaturated monocarboxylic oxide-epoxy resin. A resin obtained by reacting a carboxyl group of a monocarboxylic oxide epoxy resin with a glycidyl compound having one or more radically polymerizable unsaturated groups and an epoxy group,
The (B) particles having a core-shell structure having a core containing a polysiloxane compound are contained in an amount of 3.0 to 50 parts by mass with respect to 100 parts by mass of the (A) carboxyl group-containing photosensitive resin. A photosensitive resin composition.   The core-shell structured particles having a core containing the (B) polysiloxane compound contain 10 to 40 parts by mass with respect to 100 parts by mass of the (A) carboxyl group-containing photosensitive resin. Item 2. A photosensitive resin composition according to Item 1.   The (B) core-shell structured particles having a core containing a polysiloxane compound are core-shell structured particles having a core containing (B) a polysiloxane compound dispersed in the (E) epoxy compound. The photosensitive resin composition according to claim 1 or 2.   The shell of the particle | grains of the core shell structure which has a core containing the said (B) polysiloxane compound is an acrylic resin and / or a methacrylic resin, The any one of Claim 1 thru | or 3 characterized by the above-mentioned. Photosensitive resin composition.   The photosensitive resin composition according to any one of claims 1 to 4, wherein the block copolymer is a triblock copolymer.   The printed wiring board which has a cured film of the photosensitive resin composition of any one of Claims 1 thru | or 5. (A) a carboxyl group-containing photosensitive resin, (B) core-shell structured particles having a core containing a polysiloxane compound, (C) a photopolymerization initiator, (D) a reactive diluent, and (E) an epoxy. A compound and a block copolymer , wherein the (A) carboxyl group-containing photosensitive resin has a radical on at least a part of an epoxy group of a polyfunctional epoxy resin having two or more epoxy groups in one molecule. Reacting a polymerizable unsaturated monocarboxylic acid to obtain a radically polymerizable unsaturated monocarboxylic oxide epoxy resin, reacting a polybasic acid or its anhydride with the hydroxyl group formed by the radical polymerizable unsaturated monocarboxylic oxide epoxy resin One or more radically polymerizable unsaturated groups and an epoxy are added to the carboxyl group of the polybasic acid-modified radically polymerizable unsaturated monocarboxylic oxide epoxy resin obtained by And (B) particles of a core-shell structure having a core containing a polysiloxane compound are obtained by reacting 100 parts by weight of the (A) carboxyl group-containing photosensitive resin. A method for producing a photosensitive resin composition containing 3.0 parts by mass to 50 parts by mass , wherein (B) particles having a core-shell structure having a core containing a polysiloxane compound are premixed with the (E) epoxy compound. The manufacturing method of the said photosensitive resin composition including the process to include.