JP5051217B2 - Photosensitive composition, solder resist and photosensitive dry film - Google Patents

Description

  The present invention relates to a photosensitive composition capable of forming a fine pattern by exposure and development, a solder resist using the same, and a photosensitive dry film. More particularly, the present invention relates to a photosensitive composition that gives a cured product excellent in flame retardancy, flexibility, heat resistance, adhesion to metal and electrical insulation, a solder resist and a photosensitive dry film using the same. The photosensitive composition of the present invention is useful as a resist material, particularly as an insulating material and a solder resist material for printed wiring boards, and is useful in the field of electrical and electronic materials.

  With recent demands for multi-functionality, high integration, thinning, and miniaturization and weight reduction in electronic devices, the wiring pattern of printed wiring boards has been increased in density, and flexible and flexible wiring boards (hereinafter referred to as FPCs). Demand) is also expanding. As a result, resist materials used in the manufacture of wiring boards are required to have higher resolution and higher reliability, and the resist itself must be flexible in order to support FPC. ing.

  Furthermore, many parts used in electronic devices are required to be provided with flame retardancy according to UL standards and the like to ensure safety. In particular, in the case of FPC, the fire extinguishing action of the substrate is smaller than that of the rigid wiring board, so that the resist itself used for FPC is required to have high flame retardancy.

  As a solder resist having flame retardancy used for the production of a printed wiring board, one using a brominated epoxy compound and an antimony compound as a flame retardant (Patent Document 1) has been proposed so far.

  However, since a composition containing halogen such as bromine shows a high flame retardant effect, there is a concern that a harmful dioxin compound is generated at the time of combustion.

Non-halogen flame retardant compositions include inorganic hydroxides (Patent Document 2), phosphorus flame retardants composed of phosphate esters (Patent Document 3), and combined use of hydrated metal compounds and nitrogen compounds (Patent Document 4). )It has been known. However, inorganic filler components such as inorganic hydroxides (hydrated metal compounds) have low flame retardant effects compared to halogen flame retardants and phosphorus flame retardants, etc., so that sufficient flame retardant effects are obtained Attempts to do so may reduce insulation reliability and the like. In particular, when used in FPC applications, if the filler component is large, the flexibility of the cured product is lost and the substrate is warped. On the other hand, the flame retardant effect of a phosphorus-based flame retardant composed of a phosphate ester is relatively high, and sufficient flame retardancy is generally obtained with a smaller blending amount than inorganic hydroxides. However, flame retardants such as phosphate esters may also reduce heat resistance and insulation reliability. In addition, there is a problem that the resolution during exposure and development is greatly reduced.
Phosphinates are also known as phosphorus flame retardants (Patent Document 5).

JP-A-11-242331 JP 2006-194968 A JP 2001-183819 A JP 2004-12810 A Japanese Patent Laid-Open No. 2003-301013

As described above, the conventional solder resist composition has a problem in applying to a thin printed wiring board or FPC while maintaining flame retardancy.
The inventors of the present invention have excellent resolution and storage stability while having sufficient flame retardancy, and the cured product retains essential properties as a solder resist such as heat resistance and electrical insulation, and further flexibility. In order to find a photosensitive composition containing a non-halogen flame retardant that can be used for thin printed wiring boards and FPC boards, the present inventors have conducted intensive studies.

In order to solve the above problem, the photosensitive composition of the invention according to claim 1 is a compound (A) having a skeleton derived from an epoxy compound and having a carboxyl group and a radical polymerizable group, and a polycarbonate having no carboxyl group. Contains urethane acrylate (B) having a polyol skeleton, a polymerizable compound (C) other than (A) and (B) having a radical polymerizable group, a filler (D) containing a phosphorus atom, and a photopolymerization initiator (E). Then, based on 100 parts by mass of the total amount of the component (A) and the component (B), the component (A) is 20 to 90 parts by mass, the component (B) is 10 to 80 parts by mass, and the component (C) is 5 -50 mass parts is contained, It is characterized by the above-mentioned.
A photosensitive composition according to a second aspect of the present invention is the photosensitive composition according to the first aspect, wherein the component (D) is based on a total amount of 100 parts by mass of the component (A), the component (B) and the component (C). 1 to 150 parts by mass.
The photosensitive composition of the invention according to claim 3 is the invention according to claim 1 or 2 , wherein the compound (A) having a skeleton derived from an epoxy compound and having a carboxyl group and a radical polymerizable group is an epoxy. It is a compound obtained by an addition reaction of an unsaturated monocarboxylic acid to a compound and an addition reaction of a polybasic acid anhydride to the generated hydroxyl group.
The photosensitive composition of the invention according to claim 4 is the mass average molecular weight of urethane acrylate (B) which is a compound having a polycarbonate polyol skeleton having no carboxyl group in the invention according to any one of claims 1 to 3. Is 2,000 to 50,000.
The photosensitive composition of the invention according to claim 5 is the invention according to any one of claims 1 to 4, wherein the polymerizable compound (C) other than (A) and (B) having a radical polymerizable group is , A compound having 3 or more (meth) acryloyl groups in one molecule.
The photosensitive composition of the invention according to claim 6 is the invention according to any one of claims 1 to 5, wherein the filler (D) containing a phosphorus atom is a metal salt of phosphorus oxoacids. And
The photosensitive composition according to claim 7 is the invention according to any one of claims 1 to 5, wherein the filler (D) containing phosphorus atoms is a metal salt of phosphinic acid. .
The photosensitive composition of the invention according to claim 8 is the invention according to any one of claims 1 to 5, wherein the filler (D) containing phosphorus atoms is an aluminum salt of phosphinic acid. .
The photosensitive composition of the invention according to claim 9 contains the phosphorus compound (F) other than the filler (D) containing phosphorus atoms in the invention according to any one of claims 1 to 8. And
The solder resist of the invention described in claim 10 is characterized by containing a photosensitive composition according to any one of claims 1-9.
The photosensitive dry film of the invention described in claim 11 is characterized in that a coating containing the photosensitive composition according to any one of claims 1 to 9 is formed on a support film.
The present invention is described in detail below.
In this specification, acrylate and methacrylate are collectively referred to as (meth) acrylate. A combination of acrylic and methacrylic is called (meth) acrylic.

According to the present invention, without using a flame retardant containing a halogen atom, a photosensitivity having good resolution and storage stability that gives a cured product excellent in flame retardancy, flexibility, heat resistance, and electrical insulation. Sex composition was obtained.
Moreover, 20 to 90 parts by mass of component (A), 10 to 80 parts by mass of component (B), and 5 to 5 of component (C) based on 100 parts by mass of the total amount of component (A) and component (B). When it contains 50 mass parts, it can be set as the photosensitive composition with which the developability by aqueous alkali solution is enough, and the softness | flexibility of a cured coating film is enough.
Furthermore, when the component (D) is contained in an amount of 1 to 150 parts by mass based on 100 parts by mass of the total amount of the component (A), the component (B) and the component (C), the flame retardancy improving effect is sufficient. Thus, a photosensitive composition that does not deteriorate physical properties such as flexibility and insulation reliability of the cured film can be obtained.
In addition, compound (A) having a skeleton derived from an epoxy compound and having a carboxyl group and a radical polymerizable group is subjected to an addition reaction of an unsaturated monocarboxylic acid to the epoxy compound, and a polybasic acid anhydride is added to the generated hydroxyl group. In the case of a compound obtained by reaction, a photosensitive composition excellent in resolution and flexibility of a cured product can be obtained.
Furthermore, when urethane acrylate (B) is a compound having a polycarbonate polyol skeleton, a photosensitive composition having excellent insulation reliability of a cured product can be obtained.
Moreover, when urethane acrylate (B) is a compound which has a polycarbonate polyol frame | skeleton which does not have a carboxyl group, it can be set as the photosensitive composition excellent in the water resistance of a hardened | cured material and insulation reliability.
Furthermore, when the mass average molecular weight of the urethane acrylate (B), which is a compound having a polycarbonate polyol skeleton having no carboxyl group, is 2,000 to 50,000, the photosensitivity is excellent in resolution and flexibility of the cured product. Composition.
In addition, when the polymerizable compound (C) other than (A) and (B) having a radical polymerizable group is a compound having three or more (meth) acryloyl groups in one molecule, the cured product has high insulation. It can be set as the photosensitive composition which has reliability.
Furthermore, when the filler (D) containing a phosphorus atom is a metal salt of phosphorus oxo acid, a photosensitive composition having excellent resolution and high flame retardancy and insulation reliability is obtained. Can do.
Moreover, when the filler (D) containing a phosphorus atom is a metal salt of a phosphinic acid, the photosensitive composition is more excellent in resolution and the cured product has higher flame retardancy and insulation reliability. Can do.
Furthermore, when the filler (D) containing phosphorus atoms is an aluminum salt of a phosphinic acid, the photosensitive composition is particularly excellent in resolution and the cured product has particularly high flame retardancy and insulation reliability. Can do.
Moreover, when it also contains phosphorus compounds (F) other than the filler (D) containing a phosphorus atom, it can be set as the photosensitive composition from which the hardened | cured material with which the flame retardance was improved more effectively is obtained.
The solder resist of the present invention can also be used for processing thin printed wiring boards and FPC boards.
The photosensitive dry film of the present invention can be preferably used as an electronic material.

1. Component (A) The component (A) is a compound having a skeleton derived from an epoxy compound and having a carboxyl group and a radical polymerizable group.
As the component (A), various compounds can be used. As a preferred specific example, for example, an epoxy compound (epoxy resin) and an unsaturated monocarboxylic acid are reacted to produce a compound having a hydroxyl group. Examples include a reaction product obtained by adding a saturated or unsaturated polybasic acid anhydride (hereinafter simply referred to as polybasic acid anhydride) to a part or all of the hydroxyl group.

Examples of the epoxy resin used in that case include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, and polyphenol type epoxy resin. .
Examples of unsaturated monocarboxylic acids include acrylic acid, methacrylic acid, crotonic acid, and cinnamic acid.
Examples of the polybasic acid anhydride include maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, and trimellitic anhydride.

The reaction ratio of the polybasic acid anhydride to the compound having a hydroxyl group is not particularly limited, but the polybasic acid anhydride is preferably 0.1 to 1.0 mol per 1 mol of the hydroxyl group of the compound having a hydroxyl group. More preferably, it is 0.2 to 0.9 mol. When this ratio is less than 0.1 mol, the solubility in an alkali solution becomes insufficient, and the alkali developability of the photosensitive composition may be lowered. On the other hand, if this ratio exceeds 1.0 mol, unreacted polybasic acid anhydride will remain, and the unreacted polybasic acid anhydride may crystallize, or in many cases remain. Since the reaction between the hydroxyl group and the unreacted polybasic acid anhydride occurs during storage, the storage stability of the composition may be reduced.
Among the components described above, the component (A) is preferably a bisphenol-type epoxy (meth) acrylate having a carboxyl group because the resolution and the flexibility of the cured product are excellent. Epoxy (meth) acrylate is a compound having a structure obtained by addition reaction of (meth) acrylic acid to an epoxy compound.

2. (B) Component (B) A component is a urethane (meth) acrylate compound.
As the component (B), various commercially available products can be used, and examples thereof include a reaction product of a polyol, a polyvalent isocyanate, and a hydroxyl group-containing (meth) acrylate.
Among the components described above, the component (B) is preferably urethane (meth) acrylate having a polycarbonate polyol skeleton because it has excellent insulation reliability of the cured product.

Various commercially available products can be used as the urethane (meth) acrylate having a polycarbonate polyol skeleton, and for example, a reaction product of a polycarbonate polyol, a polyvalent isocyanate, and a hydroxyl group-containing (meth) acrylate can be used.
Examples of the polycarbonate polyol include carbonate ester having an alkylene group, an alkyl group, an aromatic hydrocarbon group, a cycloparaffinic hydrocarbon group, an alkylene group, an alkyl group, an aromatic hydrocarbon group, and a cycloparaffinic hydrocarbon. The polycarbonate polyol obtained by making the polyol which has group etc. react is mentioned.
Preferred specific examples of the carbonic acid ester are dimethyl carbonate, diethyl carbonate, diphenyl carbonate, ethylene carbonate, propylene carbonate, dicyclohexyl carbonate and the like.
Preferred specific examples of the polyol include 1,6-hexanediol, 1,4-cyclohexanedimethanol, 3-methyl-1,5-pentanediol, 1,5-pentanediol, polyoxyethylenediol, and polyoxypropylene. Diol, polyoxybutylene diol, polycaprolactone diol, trimethylhexanediol, 1,4-butanediol, and the like.
These carbonate esters and polyols may be used alone or in combination of two or more having different molecular weights or compositions.
Preferred polyisocyanates include tolylene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate and hydrogenated diphenylmethane diisocyanate.
Preferred hydroxyl group-containing (meth) acrylates include hydroxyalkyl (meth) acrylates such as hydroxyethyl (meth) acrylate and hydroxypropyl (meth) acrylate.

As the component (B), among the above, urethane (meth) acrylate having no carboxyl group is preferable because the cured product has excellent water resistance and insulation reliability.
In the preferred component (B), that is, urethane (meth) acrylate having no carboxyl group, the mass average molecular weight is preferably 2,000 to 50,000, more preferably 5,000 to 20,000. If the weight average molecular weight is less than 2,000, the cured product may have insufficient flexibility, while if it exceeds 50,000, the resolution is lowered, which is not preferable.

  A preferable blending ratio of the component (A) and the component (B) is a range in which the sum of the component (A) and the component (B) is 100 parts by mass, and the component (A) is 20 to 90 parts by mass. When the amount is less than 20 parts by mass, the developability with an alkaline aqueous solution is not sufficient, and when the amount exceeds 90 parts by mass, the flexibility of the cured product is not sufficient, which is not preferable. A more preferable range is 40 to 80 parts by mass.

3. Component (C) The component (C) is a polymerizable compound other than (A) and (B) having a radical polymerizable group.
As the radically polymerizable group of the component (C), a radically polymerizable carbon-carbon double bond is preferable, and an acryloyl group, a methacryloyl group, an allyl group, a vinyl group, or the like is particularly preferable.
Specific examples of the polymerizable compound (C) having one radical polymerizable group include methyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, hydroxyethyl (meth) acrylate and hydroxypropyl ( And monofunctional (meth) acrylates such as meth) acrylate; compounds having a vinyl group such as styrene; and compounds having an allyl group such as allylphenol.

  Specific examples of the polymerizable compound (C) having two radical polymerizable groups include 1,3-butanediol di (meth) acrylate, diethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate and polypropylene glycol di Examples include di (meth) acrylates such as (meth) acrylate; vinyl compounds such as divinylbenzene; and allyl compounds such as diallyl phthalate.

  Specific examples of the polymerizable compound (C) having three or more radical polymerizable groups include trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, and dipentaerythritol hexa (meth) acrylate. And triallyl isocyanurate.

  As the component (C), since the cured product has high insulation reliability, it is preferable to use a compound having three or more radical polymerizable groups. A compound having three or more (meth) acryloyl groups in one molecule is more preferable.

  (C) The preferable mixture ratio of a component is a range used as 5-50 mass parts with respect to a total of 100 mass parts of (A) component and (B) component, especially 5-20 mass parts. If this ratio is less than 5 parts by mass, the cross-linking density of the cured product may be insufficient and solder heat resistance and insulation reliability may be reduced. If it exceeds 50 parts by mass, the flexibility of the cured product will be reduced. There is.

4). (D) Component (D) A component is a filler containing a phosphorus atom. In the present invention, the filler means a solid that is dispersed without dissolving in the photosensitive composition at room temperature (10 to 30 ° C.). Component (D) is a component for imparting flame retardancy to the composition.
The resin [components (A), (B), (C)] is derived by using fine particles that are incompatible with the resin component in the composition, organic solvent, etc., such as a filler containing phosphorus atoms as a flame retardant component. The adverse effect on the physical properties of the composition or the cured product, in particular, the photosensitivity and the solubility in a developer can be reduced, and high resolution can be exhibited when used as a resist. Further, by containing a phosphorus atom, high flame retardancy can be obtained at a low blending amount as compared with a filler such as an inorganic hydroxide.
Specific examples of the filler containing a phosphorus atom include phosphinic acid salt compounds, diethyl phosphinic acid salt compounds, dibutyl phosphinic acid salt compounds, dihydroxymethyl acid salt compounds, ammonium polyphosphate, melamine polyphosphate, and guanidine phosphate.

Component (D) is preferably a metal salt of phosphorus oxoacid, since the photosensitive composition has high resolution and the cured product has high flame retardancy and insulation reliability. The metal salt is more preferable. In the present invention, phosphinic acid means a compound group in which phosphinic acid and a compound in which one or two hydrogen atoms bonded to the phosphorus atom of phosphinic acid are substituted with an alkyl group, an aryl group or a halogen atom are combined. The alkyl group and aryl group may have a substituent such as a hydroxyl group or an alkoxyl group.
Examples of phosphinic acids include phosphinic acid, phenylphosphinic acid, diphenylphosphinic acid, methylphosphinic acid, dimethylphosphinic acid, ethylphosphinic acid, diethylphosphinic acid, butylphosphinic acid, dibutylphosphinic acid, phenylchlorophosphinic acid, dihydroxymethylphosphine An acid etc. are mentioned.
Examples of oxo acids of phosphorus include the above phosphinic acids, phosphonic acid, diphosphonic acid, phosphoric acid, pyrophosphoric acid, metaphosphoric acid, peroxomonophosphoric acid, peroxodiphosphoric acid, diphosphoric acid, dithiophosphoric acid, phenylphosphonic acid Methylphosphonic acid, ethylphosphonic acid, hydroxymethylphosphonic acid and the like.
In addition, as elements constituting the metal salt, alkali metals such as sodium, alkaline earth metals such as magnesium, metal elements such as aluminum belonging to Group 13 of the periodic table, and transition metal elements such as iron belonging to Group 8 of the periodic table, etc. As the metal salt, an aluminum salt is particularly preferable because it easily becomes a composition having high resolution and a cured product having high flame retardancy and insulation reliability. Aluminum phosphinate is most preferred.

  The component (D) preferably has an average particle size of 0.5 to 15 μm, particularly 1 to 5 μm. When the average particle diameter exceeds 15 μm, flexibility and the like may be deteriorated. In particular, when used as a thin photosensitive dry film having a thickness of 50 μm or less, the surface state of the film may be deteriorated. On the other hand, if the average particle size is less than 0.5 μm, the bulk specific gravity of the filler containing phosphorus atoms becomes small, so that it may be difficult to disperse the filler containing phosphorus atoms in other components.

  Component (D) is preferably blended in an amount of 1 to 150 parts by weight, more preferably 10 to 100 parts by weight based on a total of 100 parts by weight of component (A), component (B) and component (C). If the amount is less than 1 part by mass, the effect of improving flame retardancy may be insufficient. On the other hand, if it exceeds 150 parts by mass, physical properties such as flexibility and insulation reliability of the cured product may be lowered.

5. (E) component (E) A component is a photoinitiator.
Component (E) is capable of initiating radical polymerization by irradiation with ultraviolet rays or the like. Specifically, benzoin and benzoin alkyl ethers such as benzoin, benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether; Acetophenones such as acetophenone, 2,2-dimethoxy-2-acetophenone, 2,2-diethoxy-2-acetophenone, 1,1-dichloroacetophenone; 2-methylanthraquinone, 2-ethylanthraquinone, 2-tertiarybutylanthraquinone, Anthraquinones such as 1-chloroanthraquinone and 2-amylanthraquinone; Thioxaxins such as thioxanthone, 2-chlorothioxanthone, 2-alkylthiothioxanthone and 2,4-dialkylthioxanthone Ton like; benzophenone, 4-chloro benzophenone, 4,4'-chloro benzophenone, 4,4'-bis-dimethylamino benzophenone benzophenone such as and the like.
(E) The compounding quantity of a component is 0.5-10 mass parts with the sum total of (A) component, (B) component, and (C) component being 100 mass parts, Especially 1-5 mass parts is preferable. If the amount is less than 0.5 parts by mass, the reaction does not start sufficiently, the mechanical strength of the coating film obtained by exposure becomes weak, and the cured coating film may peel off or the pattern may meander in the development step. On the other hand, when the amount exceeds 10 parts by mass, a large amount of the photopolymerization initiator that has not been used at the time of exposure may remain in the coating film, which may deteriorate physical properties such as heat resistance of the cured coating film.

In the present invention, it is preferable to use a sensitizer together with the component (E).
Examples of the sensitizer include N, N-dimethylaminobenzoic acid ethyl ester, N, N-dimethylaminobenzoic acid isoamyl ester, triethylamine, diethylthioxanthone, and triethanolamine. Sensitizers are commercially available. For example, trade names “Nissocure EPA, EMA, IAMA” manufactured by Nippon Steel Chemical Industries, Ltd., trade names “Kayacure EPA, DETX, DMBI” manufactured by Nippon Kayaku Co., Ltd., Osaka Organic There is a brand name “DABA” manufactured by the company.
The blending amount of these sensitizers is preferably 0.5 to 10 parts by mass, with the total of component (A), component (B) and component (C) being 100 parts by mass. If it is less than 0.5 part by mass, the reaction rate of curing by ultraviolet rays or the like may not be sufficiently improved, and if it exceeds 10 parts by mass, the reaction may be accelerated and the storage stability of the photosensitive composition may be deteriorated.

6). (F) component The photosensitive composition of this invention may be added with a phosphorus compound (F) other than the filler (D) containing a phosphorus atom. The said compound is a phosphorus compound which melt | dissolves and exists in a composition unlike the filler (D) containing a phosphorus atom.
Component (F) is also formulated for the purpose of improving flame retardancy, and acts to enhance the flame retardancy of the composition more effectively by synergistic action with component (D), which is an essential component responsible for imparting flame retardancy. .
Examples of the component (F) include phosphoric esters such as triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, triethyl phosphate, cresyl phenyl phosphate, xylyl diphenyl phosphate, resorcinol bis Condensed diphosphates such as (diphenyl) phosphate, bisphenol A bis (diphenyl) phosphate, bisphenol A bis (dicresyl) phosphate, resorcinol bis (di2,6xylenyl) phosphate, and propoxyphosphazene, And phosphazene compounds such as phenoxyphosphazene and aminophosphazene.

  Particularly preferred components (F) are condensed phosphate esters and phosphazene compounds.

The amount of component (F) to be added is preferably 1 to 50 parts by weight, and 1 to 30 parts by weight, based on a total of 100 parts by weight of component (A), component (B) and component (C). More preferably, it is 1 to 25 parts by mass. If the amount is less than 1 part by mass, the effect of improving flame retardancy by addition is insufficient. On the other hand, if the amount exceeds 50 parts by mass, the resolution and the insulation reliability of the cured coating film when the coating film is patterned by exposure and development. The physical properties such as may be reduced.
In order to suppress the adverse effect on the resolution and insulation reliability, the blending amount of the component (F) is preferably equal to or less than the blending amount of the component (D), more preferably 2/3 or less. Preferably, it is more preferably 1/2 or less.

7). (G) Component The photosensitive composition of this invention may be added with a thermal polymerization initiator (G) that generates radicals upon heating.
Examples of the component (G) include organic peroxides and initiators having an azobis structure. Dialkyl peroxides are preferred from the viewpoints of high storage stability due to a high decomposition start temperature and low generation of low molecular weight volatile components when decomposed, and specifically, dicumyl peroxide and t-butyl cumyl peroxide. Examples thereof include oxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane and 2,5-dimethyl-2,5- (t-butylperoxy) hexyne.
Moreover, the compounding quantity in the case of adding (G) component has preferable 0.5-10 mass parts on the basis of 100 mass parts in total of (A) component, (B) component, and (C) component. If the amount is less than 0.5 parts by mass, the effect of addition is insufficient, and if it exceeds 10 parts by mass, the storage stability of the composition tends to deteriorate and the amount of the decomposed product of the initiator is increased, resulting in the heat resistance of the cured product. May be damaged.

  The photosensitive composition of the present invention is preferably substantially free of an epoxy group-containing compound (hereinafter referred to as an epoxy compound). If the composition contains an epoxy compound, the storage stability of the composition may deteriorate, and the use is limited.

However, when high storage stability is not required and when it is necessary to further improve the heat resistance and chemical resistance of the cured product, an epoxy compound may be added to the photosensitive composition as necessary. In this case, the use as a two-component composition to be mixed before use is recommended.
Specific examples of the epoxy compound include a cresol novolac epoxy resin, a phenol novolac epoxy resin, an epoxy resin having an isocyanuric acid skeleton, and a bisphenol A type epoxy resin.
As the epoxy compound, a compound having two or more epoxy groups is preferable.
When using an epoxy compound, it is preferable to use a normal amine curing agent, acid curing agent, acid anhydride curing agent, and the like in combination.

8). Photosensitive Composition The photosensitive composition of the present invention is prepared by stirring and mixing the essential components (A) to (E) and, if necessary, the components (F) and (G) and other components according to a conventional method. Can be manufactured.

  As a method of using the photosensitive composition of the present invention, when used as a coating agent, an adhesive, a resist, or the like, for example, after applying the composition to a substrate, it is irradiated with active energy rays and then heated. Methods and the like.

  Examples of the base material include molded resin processed products (plastic) such as polycarbonate, polymethyl methacrylate and polyvinyl chloride, wood such as metal, glass, ceramics, concrete, natural wood and synthetic wood, stone materials and paper.

Examples of the active energy include electron beams, ultraviolet rays, and visible rays. What is necessary is just to select suitably as a light source in the case of irradiating visible light and an ultraviolet-ray according to the photoinitiator to be used, and a high pressure mercury lamp, a metal halide lamp, etc. can be mentioned. What is necessary is just to set active energy irradiation conditions etc. suitably according to the component to be used and the objective.
The heating method and conditions in the heating may be according to ordinary methods.

The photosensitive composition of the present invention can be used for various applications. Specific examples include coating agents such as paints, inks, resists, molding materials, and the like, which can be preferably used as resists, and more preferably used as solder resists.
Hereinafter, the case where the composition of the present invention is used as a resist will be described.

  When the photosensitive composition of the present invention is used as a resist, additives such as an inorganic filler, a leveling agent, an antifoaming agent, a pigment, and an ion scavenger that are usually blended in the resist may be added as necessary. . Examples of the inorganic filler include talc, clay, inorganic hydroxide and silica. Examples of the pigment include phthalocyanine blue, phthalocyanine green, and carbon black. These compounding amounts are adjusted within a range that does not impair performance such as resolution and storage stability of the composition, heat resistance, flexibility and electrical insulation of the cured product.

  When the photosensitive composition of the present invention is used as a resist, it can be used in the form of a liquid resist or a dry film resist.

  When used as a liquid resist, a high boiling point solvent may be added to the photosensitive composition of the present invention as necessary. Examples of the high boiling point solvent used in that case include ethyl cellosolve, butyl cellosolve, butyl carbitol, ethyl cellosolve acetate, butyl cellosolve acetate, ethyl carbitol acetate and butyl carbitol acetate.

  When using the photosensitive composition of the present invention as a liquid resist, the composition is applied or printed on a substrate, the coating film is dried by heating, and irradiated with active energy rays such as ultraviolet rays. Furthermore, the method of heating, etc. are mentioned.

Examples of the coating apparatus for applying the composition to the substrate include a spin coater, a roll coater, and a curtain coater. The film thickness may be appropriately set according to the purpose, but is preferably 1 to 100 μm, particularly preferably 5 to 50 μm.
Examples of the base material include metals such as silicon, aluminum, iron, nickel and copper; glass; base materials such as polyethylene terephthalate, polyimide and polycarbonate; and composite base materials such as a glass epoxy substrate.

  When forming a resist on a printed wiring board, it is preferable to form a resist after polishing the copper surface and without forming an oxide film on the copper foil surface, because higher adhesion can be obtained. Further, if the resist is formed after the unevenness is formed by performing the copper surface oxidation treatment or the rough surface treatment, the adhesion is further improved.

  When a photosensitive composition contains a solvent, after apply | coating or printing a composition, the solvent in a composition is evaporated by heating. In this case, examples of the heating device include an oven and a hot plate. What is necessary is just to set suitably as heating conditions according to the kind and objective of the composition to be used, as preferable heating temperature, 70 to 120 degreeC, and as preferable heating time, it is 5 to 30 minutes.

The coating film obtained above is irradiated with active energy rays through a photomask or the like on which a specific pattern is formed.
Examples of the active energy ray used for curing the composition include an electron beam and ultraviolet rays, and it is preferable to use ultraviolet rays because an inexpensive apparatus can be used.
The irradiation conditions of active energy rays may be according to ordinary methods. Irradiation conditions may be appropriately set according to the type and purpose of the photosensitive composition to be used, and are preferably 10 to 5,000 mJ / cm ² , more preferably 50 to 500 mJ / cm ² .

After irradiation with the active energy ray, the uncured part is alkali-developed.
What is necessary is just to select suitably as dilute alkaline aqueous solution used by image development according to the kind and objective of the photosensitive composition to be used. For example, 0.5-2% sodium carbonate aqueous solution and the like can be mentioned.
The development conditions may be appropriately set according to the type and purpose of the photosensitive composition to be used. The development temperature is preferably 15 to 50 ° C., particularly preferably 20 to 40 ° C., and the development time is 15 to 180. Seconds, particularly 30 to 120 seconds are preferred.

The photosensitive composition of the present invention can be preferably used as a solder resist, particularly as an alkali development type photographic solder resist.
In this case, after irradiating and developing active energy rays, sufficient curing can be performed by heating or irradiation with active energy rays to further improve various properties. The heating method and conditions may be appropriately set according to the type and purpose of the composition to be used. The heating temperature is preferably 100 to 250 ° C, particularly preferably 130 to 230 ° C, and the heating time is 5 minutes. ~ 5 hours, especially 30 minutes to 2 hours are preferred. The irradiation conditions of active energy rays may be according to ordinary methods. Irradiation conditions may be appropriately set according to the type and purpose of the composition to be used, and are preferably 10 to 5,000 mJ / cm ² , more preferably 500 to 3,000 mJ / cm ² .

When the photosensitive composition of the present invention is used as a photosensitive layer of a dry film, the dry film is produced by applying the composition of the present invention to a support film such as polyethylene terephthalate and removing the solvent by heating and drying. Thereafter, a method of superimposing a polyolefin film such as polypropylene as a cover film may be used. The thickness of the composition coating film (resist layer) is preferably 1 to 200 μm, particularly preferably 5 to 50 μm.
In this case, you may add the solvent suitable for coating of the support film to be used. It is necessary to volatilize the solvent in the composition at a heating temperature and time such that the composition does not polymerize after film coating. Examples of the solvent for that purpose include those having a relatively low boiling point such as methyl ethyl ketone, ethyl acetate, butyl acetate, methanol and ethanol.

Below by experimental examples and comparative examples illustrate the present invention more specifically.
In the following experimental examples and comparative examples, "parts" means parts by mass, means mass% and "%".

* Synthesis example 1 [production of component (A)]
In a four-necked flask equipped with a thermometer, a stirrer and a cooler, 950 g (5.0 epoxy equivalent) of bisphenol A type epoxy resin (manufactured by Yuka Shell Epoxy Co., Ltd., trade name “Epicoat 828”) and 450 g of toluene as a solvent were added. And heated to 110 ° C. to obtain a uniform solution. To this solution, 0.50 g of phenothiazine as a polymerization inhibitor, 10 g of tetrabutylammonium bromide and 360 g of acrylic acid (5.0 carboxyl equivalent) as a catalyst are added and reacted at 110 ° C. while blowing air to contain an acryloyl group and a hydroxyl group. A compound (epoxy acrylate) was prepared. The acrylic acid consumption rate calculated from the acid value was almost 100%.
To the solution of the above product, 220 g (1.5 mol) of phthalic anhydride was added and heated to 110 ° C. to completely dissolve the phthalic anhydride, and further reacted for 3 hours. After adding 1040 g of butyl cellosolve to this solution, 300 g of toluene was removed under reduced pressure to obtain an epoxy acrylate having a carboxyl group (a-1) as a solution having a solid content of 60%.

* Synthesis example 2 [production of component (B)]
A 4-necked flask equipped with a thermometer, a stirrer and a condenser was charged with 64 g of tolylene diisocyanate and 200 ppm of dibutyltin dilaurate, and maintained at 70 ° C. while maintaining a polycarbonate diol [Toagosei Co., Ltd., ethylene carbonate and 1,6-hexane. 390 g of carbonate diol which is a reaction product of diol] was gradually added with stirring, and the mixture was stirred for 1 hour to be reacted. To this solution, 50 ppm of dibutyltin dilaurate was added, and 48 g of 2-hydroxyethyl acrylate was gradually added while stirring and maintained at 70 ° C., and the reaction product was analyzed by infrared absorption spectrum. The reaction was continued until it was confirmed that the characteristic absorption disappeared.
As a result, 500 g of urethane acrylate (b-1) having a polycarbonate polyol skeleton having no carboxyl group was obtained as a rubber-like solid.

* Synthesis example 3 [production of component (B)]
A 4-necked flask equipped with a thermometer, a stirrer and a condenser was charged with 72 g of tolylene diisocyanate and 50 ppm of dibutyltin dilaurate, and maintained at 70 ° C., while maintaining a temperature of 70 ° C., 280 g of polycarbonate diol (trade name “PCDL T6001” manufactured by Asahi Kasei Chemicals) And 12 g of dimethylolpropionic acid were gradually added with stirring and reacted for 1 hour with stirring. To this solution, 50 ppm of dibutyltin dilaurate was added, and 17 g of 2-hydroxyethyl acrylate was gradually added while stirring and maintained at 70 ° C., and the reaction product was analyzed by infrared absorption spectrum. The reaction was continued until it was confirmed that the characteristic absorption disappeared.
As a result, 380 g of urethane acrylate (b-3) having a polycarbonate polyol skeleton having a carboxyl group was obtained as a rubber-like solid.

* Synthesis example 4 [manufacture of (B) component]
A 4-necked flask equipped with a thermometer, a stirrer and a condenser was charged with 33 g of hexamethylene diisocyanate and 50 ppm of dibutyltin dilaurate, and maintained at 70 ° C., while maintaining a polycarbonate diol (trade name “PCDL T5650J” manufactured by Asahi Kasei Chemicals Corporation) 100 g Was gradually added with stirring, and the reaction was allowed to stir for 30 minutes. To this solution was added 50 ppm of dibutyltin dilaurate, and 24 g of 2-hydroxyethyl acrylate was gradually added while stirring and maintaining at 70 ° C., and the reaction product was analyzed by infrared absorption spectrum. The reaction was continued until it was confirmed that the characteristic absorption disappeared.
As a result, 156 g of urethane acrylate (b-4) having a polycarbonate polyol skeleton having no carboxyl group was obtained as a rubber-like solid.

* Synthesis example 5 [production of component (B)]
A 4-necked flask equipped with a thermometer, a stirrer and a condenser was charged with 34 g of hexamethylene diisocyanate and 50 ppm of dibutyltin dilaurate and maintained at 70 ° C. while maintaining a polyester diol (trade name “PES-360” manufactured by Toagosei Co., Ltd.). 1000 g and 200 g of polycarbonate diol (manufactured by Asahi Kasei Chemicals Corporation, trade name “PCDL T5652”) were gradually added under stirring and reacted for 1 hour with stirring. To this solution, 50 ppm of dibutyltin dilaurate was added, and 13 g of 2-hydroxyethyl acrylate was gradually added while stirring and maintained at 70 ° C., and the reaction product was analyzed by infrared absorption spectrum. The reaction was continued until it was confirmed that the characteristic absorption disappeared.
As a result, 1246 g of urethane acrylate (b-5) having a polycarbonate polyol skeleton having no carboxyl group was obtained as a rubber-like solid.

〇 Experiment Examples 1 to 11 and Comparative Examples 1 to 7
Using 1 part of 2,4-diethylthioxanthone (sensitizer) and methyl ethyl ketone (solvent) and the components (A) to (J) shown below in solid content ratios according to the mixing ratios shown in Tables 1 and 2 below. These were kneaded with three rolls to prepare a composition having a solid content of 65%. Experimental examples 1, 3-8, 10 and 11 are examples, and experimental examples 2 and 9 are reference examples.

The numerical values in the column of each component in Table 1 and Table 2 mean parts by mass. Moreover, the meaning of the symbol of each component is as follows.
(A-1): Epoxy acrylate having carboxyl group obtained in Synthesis Example 1 (b-1): Polyurethane polyol skeleton urethane acrylate having no carboxyl group obtained in Synthesis Example 2 [mass average molecular weight 8000]
(B-2): Polyester polyol type urethane acrylate [Shin Nakamura Chemical Co., Ltd. "U-200AX", number average molecular weight 13000]]
(B-3): Urethane acrylate of a polycarbonate polyol skeleton having a carboxyl group obtained in Synthesis Example 3 [mass average molecular weight 10,000]
(B-4): Polyurethane polyol skeleton urethane acrylate having no carboxyl group obtained in Synthesis Example 4 [mass average molecular weight 1800]
(B-5): Polyurethane polyol skeleton urethane acrylate having no carboxyl group obtained in Synthesis Example 5 [mass average molecular weight 60000]
(C-1): Dipentaerythritol [Composition comprising pentaacrylate and dipentaerythritol hexaacrylate (trade name “Aronix M-400” manufactured by Toagosei Co., Ltd.)
(C-2) Pentaerythritol diacrylate monostearate (trade name “Aronix M-233” manufactured by Toagosei Co., Ltd.)
(D-1): Aluminum diethylphosphinate [manufactured by Clariant Japan, trade name “EXOLIT OP-930”, average particle size of about 5 μm, P content 23%]
(D-2): Melamine polyphosphate [manufactured by Sanwa Chemical Co., Ltd., trade name “MPP-B”, average particle size 12 μm, P content 13%]
(D-3): ammonium polyphosphate [manufactured by Suzuyu Chemical Co., Ltd., trade name “FCP-720”, average particle size 20 μm, P content 13%]
(E-1): Photopolymerization initiator, 2-methyl- [4- (methylthio) phenyl] -2-morpholino-1-propanone (trade name “Irgacure 907” manufactured by Ciba Specialty Chemicals)
(F-1): Aromatic condensed phosphate ester [manufactured by Daihachi Chemical Co., Ltd., trade name “PX-200”, P content 14%]
(F-2): Polyphosphazene [manufactured by Otsuka Chemical Co., Ltd., trade name “SPB-100”, P content 13%]
(G-1): Thermal polymerization catalyst, dicumyl peroxide [manufactured by NOF Corporation, trade name “Park Mill D”]
(H-1): Bisphenol A type epoxy resin (Oilized Shell Epoxy, trade name “Epicoat 828”)
(I-1): Melamine [(h-1) Curing agent for epoxy resin]
(J-1): Magnesium hydroxide [inorganic hydroxide flame retardant, manufactured by Kyowa Chemical Industry Co., Ltd., trade name “Kisuma 5A”, average particle size 1 μm]

  The photosensitive composition is coated on a polyethylene terephthalate film (base film) having a thickness of 25 μm and heated at 100 ° C. for 10 minutes to evaporate volatile components. 30 μm) was formed. Thereafter, a polyethylene film (cover film) having a thickness of 25 μm was bonded onto the coating to prepare a dry film.

The cover film was peeled off when evaluating the dry film. While the dry film from which the cover film was peeled off was heated to 70 ° C., it was laminated using a laminator so that the coating of the photosensitive composition (hereinafter also referred to as a photosensitive layer) was adhered to the substrate described later. The substrate with a photosensitive layer thus obtained is a substrate in which a photosensitive layer is formed on a substrate and a base film is coated thereon.
With respect to the substrate with the photosensitive layer, the resolution, storage stability, flame retardancy, substrate warpage, bending resistance, solder heat resistance and insulation reliability were evaluated according to the following methods. The evaluation results are shown in Table 3 and Table 4.

(Resolution and storage stability)
An FR-4 substrate (manufactured by Sumitomo Bakelite Co., Ltd., copper foil thickness: 18 μm) was used as the substrate. The photosensitive layer of the prepared substrate with a photosensitive layer was exposed with a light amount of 250 mJ / cm ² using a photomask having a line width pattern of 60 μm, 80 μm, 100 μm and 200 μm. The photomask was placed on the base film, and exposure to the photosensitive layer was made through the photomask and the base film. After the exposure, the base film is peeled off, and a 1% concentration sodium carbonate aqueous solution is sprayed at a temperature of 30 ° C. for 60 seconds at a pressure of 1.5 kg / cm ² , thereby removing the unexposed portion of the photosensitive layer for alkali development. A test piece was obtained. The obtained test piece was observed with a microscope, and the state of the photosensitive layer cured film was evaluated in the following three stages.
〇 ・ ・ ・ No abnormalities.
Δ: Some abnormalities (residue, peeling, meandering, etc.) were observed.
X: Abnormalities (residue, peeling, meandering, etc.) were observed on the entire surface.
The storage stability was evaluated by evaluating the resolution of a test piece prepared by exposing a substrate with a photosensitive layer in the same manner as described above after storing the dry film at 15 ° C. for 1 month.

(Flame retardance)
A 25 μm-thick polyimide film (manufactured by Toray DuPont, trade name “Kapton”) was used as the substrate. The substrate with the photosensitive layer was exposed with a light amount of 1000 mJ / cm ² . Subsequently, the base film was peeled off and post-cured at 160 ° C. for 30 minutes to obtain a test piece.
Using the above test piece, flame retardancy was evaluated according to the thin material vertical combustion test method of UL-94 standard.

(Board warpage)
A 25 μm-thick polyimide film (manufactured by Toray DuPont, trade name “Kapton”) was used as the substrate. The substrate with the photosensitive layer was exposed with a light amount of 1000 mJ / cm ² . Next, the base film was peeled off, post-cured at 160 ° C. for 30 minutes, and cut into 100 mm squares to obtain test pieces.
The height of the test piece from the corner floor was measured in mm on a horizontal floor, and the average value was evaluated as the magnitude of warpage.
X: Warping could not be measured because the film curled completely.

(Flexibility)
A 25 μm-thick polyimide film (manufactured by Toray DuPont, trade name “Kapton”) was used as the substrate. The substrate with the photosensitive layer was exposed with a light amount of 1000 mJ / cm ² . Next, the base film was peeled off, post-cured at 160 ° C. for 30 minutes, and cut into 100 mm squares to obtain test pieces.
The test piece was bent at 90 ° or 180 ° so that the photosensitive layer was on the outside, and the damage of the photosensitive layer such as cracks was visually observed and evaluated in the following three stages.
O: There was no abnormality in the photosensitive layer.
Δ: Abnormality (crack, etc.) on the surface of the photosensitive layer.
X: Cracks reached the lower surface of the photosensitive layer.

(Solder heat resistance)
An FR-4 substrate (manufactured by Sumitomo Bakelite Co., Ltd., copper foil thickness: 18 μm) was used as the substrate. The substrate with the photosensitive layer was exposed with a light amount of 1000 mJ / cm ² . Subsequently, the base film was peeled off and post-cured at 160 ° C. for 30 minutes to obtain a test piece. The test piece was immersed in a molten solder bath at 280 ° C. for 10 seconds as one cycle, and after 5 cycles, the state of the cured film was visually observed and evaluated in the following three stages.
O: The photosensitive layer did not peel off.
Δ: A part of the photosensitive layer was peeled off.
X: Most of the photosensitive layer was peeled off or completely peeled off.

(Insulation reliability)
Using a comb type test pattern substrate (line width: 100 μm, line spacing: 100 μm) prepared from an FR-4 substrate (manufactured by Sumitomo Bakelite Co., Ltd., copper foil thickness: 18 μm), the substrate with the photosensitive layer was exposed with a light amount of 1000 mJ / cm ² . . Subsequently, the base film was peeled off and post-cured at 160 ° C. for 30 minutes to obtain a test piece. The insulation resistance value was measured after leaving the test piece for 250 hours, 500 hours, and 1000 hours in a state where 50 V DC was applied in an atmosphere of 85 ° C. and 85% relative humidity.
× ・ ・ ・ The wiring is short-circuited and the resistance value cannot be measured.

According to Table 3, the Experiment Example 1, 3-8, resolution, storage stability, flame retardancy, of the substrate warp, a better one of the results of the flex resistance and solder heat insulation reliability, Although the resistance may slightly decrease after storage for 1000 hours, it is found that the range is practically free from any problems. Also, in Experiment Example 9 using a urethane acrylate of the polycarbonate polyol skeleton having a carboxyl group, there is a tendency that the insulation reliability is lowered slightly. Furthermore, although using a urethane acrylate having no polycarbonate polyol backbone carboxyl group, in the weight-average molecular weight is less experimental example 10, the substrate warpage and bending resistance is slightly reduced, weight-average molecular weight is larger experimental example 11, the resolution tends to decrease.

  On the other hand, according to Table 4, in Comparative Examples 1-7, it turns out that it is inferior in several evaluation items. In particular, the resolution is inferior in all the comparative examples, and the insulation reliability is greatly inferior except for Comparative Example 6, and it cannot be said that the insulation reliability of Comparative Example 6 is also excellent.

The photosensitive composition of the present invention can be preferably used as an electronic material such as a resist, particularly a solder resist, in addition to providing a photosensitive dry film by being coated on a film support, for example, and can be used as a thin printed wiring board or FPC. It can also be used for substrate processing.
Moreover, it can be used also as coating agents, such as a coating material, and ink.

Claims (11)

Compound (A) having a skeleton derived from an epoxy compound and having a carboxyl group and a radical polymerizable group, urethane acrylate (B) having a polycarbonate polyol skeleton having no carboxyl group, (A) and (A having a radical polymerizable group Containing a polymerizable compound (C) other than B), a filler (D) containing a phosphorus atom and a photopolymerization initiator (E) ;
20 to 90 parts by mass of component (A), 10 to 80 parts by mass of component (B), and 5 to 50 of component (C) based on 100 parts by mass of the total amount of component (A) and component (B). A photosensitive composition containing parts by mass .   The photosensitive composition of Claim 1 which contains 1-150 mass parts of components (D) on the basis of 100 mass parts of total amounts of a component (A), a component (B), and a component (C). In the compound (A) having a skeleton derived from an epoxy compound and having a carboxyl group and a radical polymerizable group, an unsaturated monocarboxylic acid is added to the epoxy compound, and a polybasic acid anhydride is added to the generated hydroxyl group. the photosensitive composition according to claim 1 or 2, characterized in that a compound obtained Te. The weight average molecular weight of the urethane acrylate (B) is a compound having a polycarbonate polyol skeleton having no carboxyl group, the photosensitive according to claim 1, characterized in that the 2,000-50,000 Sex composition. Having a radical polymerizable group (A) and (B) other than the polymerizable compound (C), according to claim 1-4, characterized in that a compound having 3 or more in one molecule (meth) acryloyl groups The photosensitive composition in any one of. The photosensitive composition according to any one of claims 1 to 5, wherein the filler (D) containing a phosphorus atom is a metal salt of an oxo acid of phosphorus. The photosensitive composition according to any one of claims 1 to 5, wherein the filler (D) containing a phosphorus atom is a metal salt of a phosphinic acid. The photosensitive composition according to any one of claims 1 to 5, wherein the filler (D) containing a phosphorus atom is an aluminum salt of a phosphinic acid. The photosensitive composition in any one of Claims 1-8 which also contains phosphorus compounds (F) other than the filler (D) containing a phosphorus atom. Solder resist containing a photosensitive composition according to any one of claims 1-9. Photosensitive dry film coating containing the photosensitive composition formed on a support film according to any one of claims 1-9.