JP2010117452A - Photosensitive flame retardant resin composition - Google Patents

Abstract

The present invention relates to an interlayer electrical insulating material, an optical waveguide, a printed wiring board, particularly a polyimide, a copper substrate adhesion, a fine pattern required as a photo solder resist or a coverlay film for flexible printed wiring board applications. It is an object of the present invention to provide a photosensitive flame retardant resin composition that has both physical properties such as developability, solder heat resistance, insulation and chemical resistance, as well as flexibility and folding resistance.
A urethane resin (A) having a carboxyl group and an ethylenically unsaturated group;
A photosensitive flame retardant comprising 5 to 50 parts by weight of a phosphinic acid salt (B) having a volume average particle diameter of 0.1 to 1 μm with respect to 100 parts by weight of a urethane resin (A). Resin composition.
[Selection figure] None

Description

  The present invention relates to a photosensitive flame retardant resin composition that is suitable as a solder resist or plating resist for printed wiring boards, particularly flexible printed wiring boards, and is also useful as an interlayer electrical insulating material, a photosensitive optical waveguide, and the like.

  A protective layer called a coverlay or solder resist is formed on the printed wiring board for the purpose of protecting the wiring circuit during and after manufacturing, such as the soldering process performed when surface mounting electronic components during manufacturing. ing.

  For example, information devices such as mobile phones and digital cameras often use flexible printed wiring boards in addition to rigid wiring boards in order to increase functionality, reduce size, and the like. Because flexible printed wiring boards are mainly used in the bent and connected areas of equipment, the photo solder resist used for them has a high degree of flexibility and fold resistance, and developability that can realize fine patterns. In addition, performance that satisfies solder heat resistance, substrate adhesion, insulation, and the like is required.

Under such circumstances, many proposals have been made as flexible and folding-resistant photo solder resists. Among them, a resist ink composition using a resin having a urethane main skeleton is excellent in flexibility and resistance. Folding can be obtained (see Patent Document 1).
In addition, flame retardance is often required for electronic materials, and a flame retardant is often added as a resist ink composition. Conventionally, halogen flame retardants have been used as flame retardants, but it is desired to use non-halogen flame retardants from the viewpoint of the environment.

However, when a hydrated metal compound or nitrogen compound is used as a non-halogen flame retardant, it is necessary to add a large amount of the above compound in order to obtain sufficient flame retardancy. As a result, a photo solder for a flexible printed circuit board The substrate adhesion, flexibility, and folding resistance required as a resist will not be satisfactory.
On the other hand, phosphazenes among phosphorus-based flame retardants can achieve flame retardancy in a relatively small amount compared to the above compounds. It will no longer satisfy the high flexibility and folding resistance required as a solder resist.
In addition, since the concentration of phosphorus in a compound such as a polyphosphate compound is high, flame retardancy can be achieved in an amount smaller than that of the phosphorus-based flame retardant, but it causes a decrease in electrical insulation. .

  In such a case, when a phosphinate is used as a flame retardant, flame retardancy can be achieved with a small addition amount, and electric insulation can be satisfied (see Patent Document 2). However, phosphinates that are generally commercially available are in the form of fillers that are insoluble in solvents and have a particle size of several micrometers. Therefore, the developability that can realize flexibility and folding resistance and high-precision patterning is insufficient for use as a photo solder resist for a flexible printed circuit board.

As described above, a non-halogen photosensitive flame retardant resin composition that satisfies the physical properties required for a photoresist for a flexible printed wiring board and a cured product thereof have not been obtained.
JP 2001-159815 A JP 2007-270137 A

  The present invention is an interlayer electrical insulating material, an optical waveguide, a printed wiring board, particularly required as a photo solder resist or coverlay film for flexible printed wiring board applications, developability capable of realizing high-precision patterning, solder heat resistance, It is an object of the present invention to provide a photosensitive flame retardant resin composition that realizes electrical insulation, flame retardancy, sufficient substrate adhesion, flexibility and bendability.

  In order to solve the above-mentioned problems, the present inventors have intensively studied, and as a result, a photosensitive flame retardant resin composition containing a specific carboxyl group-containing photosensitive urethane resin and a specific phosphinate solves the above-mentioned problem. As a result, the present invention has been completed.

The present invention relates to a urethane resin (A) having a carboxyl group and an ethylenically unsaturated group,
A photosensitive flame retardant comprising 5 to 50 parts by weight of a phosphinic acid salt (B) having a volume average particle diameter of 0.1 to 1 μm with respect to 100 parts by weight of a urethane resin (A). The present invention relates to a resin composition.

Further, in the present invention, the urethane resin (A) is
A carboxyl group in the carboxyl group-containing urethane prepolymer (a);
A hydroxyl group in the hydroxyl group-containing urethane prepolymer (c) obtained by reacting an epoxy group or oxetane group in the compound (b) having an epoxy group or oxetane group and an ethylenically unsaturated group;
The present invention relates to the above-mentioned photosensitive flame retardant resin composition characterized by reacting with an acid anhydride group in the polybasic acid anhydride (d).

Furthermore, the present invention relates to the photosensitive flame retardant resin composition according to any one of the above inventions, wherein the phosphinic acid salt (B) is represented by the following general formula (1).
General formula (1)

(R1 and R2 are the same or different and represent a linear or branched alkyl group having 1 to 6 carbon atoms or an aryl group, and M represents Mg, Ca, Al, Sb, Sn, Ge, Ti. , Zn, Fe, Zr, Ce, Bi, Sr, Mn, Li, Na, and at least one metal selected from the group consisting of K, and n is an integer of 1 to 4.

  Furthermore, this invention relates to the hardened | cured material formed by hardening | curing the photosensitive flame-retardant resin composition of one of the said inventions.

  Furthermore, this invention relates to the printed wiring board by which the cured film of the photosensitive flame-retardant resin composition of any one of said invention is laminated | stacked.

  According to the present invention, it has excellent sensitivity to light and can form a highly accurate pattern by a development photolithography process using a dilute alkaline aqueous solution, and the obtained cured film has excellent substrate adhesion, flexibility and bendability. Furthermore, it is possible to provide a photosensitive flame retardant resin composition excellent in flame retardancy, high insulation, solder heat resistance, coating film resistance, and the like, and a cured product thereof. The photosensitive flame retardant resin composition of the present invention can be suitably used as a solder resist for flexible printed wiring boards, coverlay films, plating resists, interlayer electrical insulating materials for wiring boards, optical waveguides and the like.

  The flame-retardant resin composition of the present invention is required for a photo solder resist, a coverlay film, and the like, and developability, solder heat resistance, electrical insulation, flame retardancy, and sufficient substrate adhesion that can realize high-precision patterning. It aims at providing the flame retardant resin composition which implement | achieved property, flexibility, and bendability.

First, the urethane resin (A) having a carboxyl group and an ethylenically unsaturated group (hereinafter, also simply referred to as “urethane resin (A)”) of the present invention will be described.
The urethane resin (A) of the present invention is an epoxy group in the compound (b) having an epoxy group or an oxetane group and an ethylenically unsaturated group with respect to 1 mol of the carboxyl group in the carboxyl group-containing urethane prepolymer (a). Alternatively, the oxetane group is preferably reacted at a ratio of 0.1 mol to 1.0 mol, more preferably at a ratio of 0.30 mol to 0.95 mol to prepare a hydroxyl group-containing urethane prepolymer (c), The ratio of the acid anhydride group in the polybasic acid anhydride (d) to the hydroxyl group in the hydroxyl group-containing urethane prepolymer (c) is preferably 0.1 mol to 1.0 mol, more preferably 0.00. It can obtain by making it react in the ratio of 30 mol-0.95 mol. In addition, the molar ratio of the functional group at the time of reaction demonstrated by this invention is not a measured value but the numerical value calculated from the theoretical value of each raw material is used.

  Here, with respect to the carboxyl group in the carboxyl group-containing urethane prepolymer (a), the ratio of reacting the epoxy group or oxetane group in the compound (b) having an epoxy group or oxetane group and an ethylenically unsaturated group, When the amount is less than 0.1 mol, the amount of ethylenically unsaturated groups in the finally obtained carboxyl group-containing photosensitive urethane resin (a) decreases, and the desired photosensitivity and phosphinic acid salt are obtained in the photosensitive resin composition. It is difficult to obtain fine dispersion stability of particles.

  Theoretically, the epoxy group or oxetane group in the compound (b) having an epoxy group or oxetane group and an ethylenically unsaturated group with respect to 1 mol of carboxyl group in the carboxyl group-containing urethane prepolymer (a) is 1. It is not possible to react in amounts greater than 0 mole.

  When the polybasic acid anhydride (d) is further reacted with 1 mol of the hydroxyl group in the hydroxyl group-containing urethane prepolymer (c), the ratio of reacting the acid anhydride group in (d) is 0.1 mol. If it is less than 1, the ratio of introducing a carboxyl group decreases, and it is difficult to obtain desired developability in the photosensitive resin composition.

  Theoretically, the acid anhydride group in the polybasic acid anhydride (d) cannot be reacted in an amount larger than 1.0 mol with respect to 1 mol of the hydroxyl group in the hydroxyl group-containing urethane prepolymer (c).

  The carboxyl group-containing urethane prepolymer (a) can be produced by reacting a polymer polyol (e), a carboxylic acid compound (f) having two hydroxyl groups in the molecule, and a diisocyanate compound (g). Preferably, further, a hydroxyl group-containing compound (h) [excluding the “polymer polyol (e)” and the “carboxylic acid compound (f) having two hydroxyl groups in the molecule”] and an isocyanate group in the molecule It is also preferable to react the isocyanate compound (i) having 1 or 3 or more with the amine compound (j) as appropriate.

In the present invention, when the carboxyl group-containing urethane prepolymer (a) is synthesized, the following starting materials are reacted in the proportions of the polymer polyol (e) and the carboxylic acid compound (f) having two hydroxyl groups in the molecule. In addition, when the hydroxyl group-containing compound (h) and the amine compound (j) to be added in some cases are totaled, when the total of the hydroxyl group and amino group contained in these is converted to 1 mol, the diisocyanate compound (g) and the molecule The total of isocyanate groups contained in the isocyanate compound (i) having one or three or more isocyanate groups is preferably reacted in a proportion of 0.50 mol to 1.00 mol, from 0.70 mol to 0 More preferably, the reaction is carried out at a ratio of 95 moles. When the isocyanate group is less than 0.50 mol, the molecular weight of the carboxyl group-containing urethane prepolymer (a) becomes small, making it difficult to obtain desired coating film resistance and film formability. Moreover, when there are more isocyanate groups than 1.00 mol, there exists a possibility that the excess isocyanate group may remain in the system, and a by-product may be generated in the subsequent reaction step or gelation may occur during the reaction. In addition, when the carboxyl group-containing urethane prepolymer (a) is synthesized, the polymer polyol (e), the carboxylic acid compound (f) having two hydroxyl groups in the molecule, and the hydroxyl group-containing compound (h) optionally added And a carboxylic acid having two hydroxyl groups in the molecule at a ratio such that the acid value of the carboxyl group-containing urethane prepolymer (a) finally obtained is 5 to 200 mgKOH / g for the amine compound (j) It is also preferable to add the compound (f) (more preferably 10 to 180 mgKOH / g).

  The polymer polyol (e) used in the present invention is a compound containing two or more hydroxyl groups, and preferably has a weight average molecular weight in terms of polystyrene as measured by gel permeation chromatography (hereinafter also referred to as “GPC”) of 500. ~ 50,000 compounds. In the present specification, unless otherwise specified, the weight average molecular weight means a polystyrene equivalent weight average molecular weight by GPC measurement.

In the present invention, as the polymer polyol (e), polyethylene oxide, polypropylene oxide, block copolymer or random copolymer of ethylene oxide / propylene oxide, polytetramethylene glycol, block copolymer of tetramethylene glycol and neopentyl glycol are used. Polyether polyols such as polymers or random copolymers;
Polyester polyols which are condensates of polyhydric alcohols or polyether polyols with polybasic acids such as maleic anhydride, maleic acid, fumaric acid, itaconic anhydride, itaconic acid, adipic acid, isophthalic acid;
Polycarbonate polyols obtained by reaction of glycol or bisphenol with a carbonic acid ester or reaction of phosgene with glycol or bisphenol in the presence of alkali;
Examples thereof include caprolactone-modified polyol such as caprolactone-modified polytetramethylene polyol, polyolefin polyol, polybutadiene polyol such as hydrogenated polybutadiene polyol, and polyol such as silicone polyol. In the present invention, these polymer polyols (e) may be used alone or in combination.

  Among these, polyether polyols such as polytetramethylene glycol, block copolymer of tetramethylene glycol and neopentyl glycol or random copolymer are excellent in flexibility, hydrolysis resistance, and hydrophilicity of the skeleton. When used in the invention, the cured film is particularly preferred because of its excellent flexibility, chemical resistance, developability, and the like.

  The “carboxylic acid compound (f) having two hydroxyl groups in the molecule” (hereinafter also simply referred to as “carboxylic acid compound (f)”) used in the present invention has two hydroxyl groups and one or more in the molecule. A compound having (preferably 1 to 3) carboxyl groups is preferred, and a compound having a molecular weight or weight average molecular weight of 90 to 1000 is preferred. For example, dimethylolbutanoic acid, dimethylolpropionic acid, and derivatives thereof (caprolactone adduct, ethylene oxide adduct, propylene oxide adduct, etc.), 3-hydroxysalicylic acid, 4-hydroxysalicylic acid, 5-hydroxysalicylic acid, 2- Examples include carboxy-1,4-cyclohexanedimethanol.

Among these, dimethylolbutanoic acid and dimethylolpropionic acid are preferable in the present invention in that the carboxyl group concentration in the urethane resin can be increased. In addition, caprolactone adducts, ethylene oxide adducts, propylene oxide adducts and the like can reduce the amount of urethane bonds in the carboxyl group-containing urethane prepolymer (a), so that the flexibility of the cured film is improved. Can be used in Furthermore, aromatic compounds such as hydroxysalicylic acid can be used for the purpose of improving the heat resistance of the cured film.
As described above, in the present invention, these carboxylic acid compounds (f) can be appropriately selected and used according to the purpose and application, and may be used alone or in combination. Also good.

  As a diisocyanate compound (g) used by this invention, C4-C50 aromatic diisocyanate, aliphatic diisocyanate, araliphatic diisocyanate, alicyclic diisocyanate etc. can be mentioned, for example.

  Examples of the aromatic diisocyanate include 1,3-phenylene diisocyanate, 4,4′-diphenyl diisocyanate, 1,4-phenylene diisocyanate, 4,4′-diphenylmethane diisocyanate, 2,4-tolylene diisocyanate, 2,6- Tolylene diisocyanate, 4,4'-toluidine diisocyanate, 2,4,6-triisocyanate toluene, 1,3,5-triisocyanate benzene, dianisidine diisocyanate, 4,4'-diphenyl ether diisocyanate, 4,4 ', 4 "-Triphenylmethane triisocyanate etc. can be mentioned.

  Examples of the aliphatic diisocyanate include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, dodecamethylene diisocyanate, 2 4,4-trimethylhexamethylene diisocyanate and the like.

  Examples of the araliphatic diisocyanate include ω, ω′-diisocyanate-1,3-dimethylbenzene, ω, ω′-diisocyanate-1,4-dimethylbenzene, ω, ω′-diisocyanate-1,4-diethylbenzene, 1 , 4-tetramethylxylylene diisocyanate, 1,3-tetramethylxylylene diisocyanate, and the like.

  Examples of the alicyclic diisocyanate include 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate [also known as: isophorone diisocyanate], 1,3-cyclopentane diisocyanate, 1,3-cyclohexane diisocyanate, and 1,4-cyclohexane diisocyanate. , Methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, 4,4′-methylenebis (cyclohexyl isocyanate), 1,3-bis (isocyanatomethyl) cyclohexane, 1,4-bis (isocyanate methyl) A cyclohexane etc. can be mentioned.

  In the present invention, when improving the heat resistance of the photosensitive flame retardant resin composition, it is preferable to use an aromatic diisocyanate or an aliphatic diisocyanate, and when improving the flexibility of the intended photosensitive resin composition. It is preferable to use an aliphatic diisocyanate or an alicyclic diisocyanate. In the present invention, these diisocyanate compounds (g) can be appropriately selected and used according to the purpose and application, or only one kind may be used alone or a plurality may be used in combination.

  The hydroxyl group-containing compound (h) used in the present invention is a compound having one or more hydroxyl groups, but the compound belonging to the “polymer polyol (e)” and the “carboxylic acid compound having two hydroxyl groups in the molecule ( f) a compound excluding the compound belonging to “,” and representative examples thereof include, for example, a monoalcohol compound (h1) having one hydroxyl group in the molecule, two hydroxyl groups in the molecule, and a carboxyl group. Diol compound (h2) having a molecular weight or weight average molecular weight of 50 to 499, polyhydric alcohol compound having three or more hydroxyl groups in the molecule and having a molecular weight or weight average molecular weight of 50 to 499 (h3) ). These may have both a hydroxyl group and a functional group other than a hydroxyl group in the molecule. Moreover, you may use individually and may use it in combination of multiple.

Examples of the monoalcohol compound (h1) having one hydroxyl group in the molecule include aliphatics such as methanol, ethanol, N-propanol, isopropanol, N-butanol, isobutanol, tertiary butanol, lauryl alcohol, and stearyl alcohol. Monoalcohol;
Alicyclic monoalcohols such as cyclohexanol;
Aromatic monoalcohols such as benzyl alcohol, fluorenol, phenol, and methoquinone;
Examples of monoalcohol compounds having functional groups other than hydroxyl groups include hydroxyl group-containing carboxylic acid compounds such as 12-hydroxystearic acid, 2-hydroxyethyl (meth) acrylate (“2-hydroxyethyl acrylate” and “2-hydroxyethyl methacrylate” And the like, the same shall apply hereinafter), a hydroxyl group-containing (meth) acrylate compound such as 4-hydroxybutyl (meth) acrylate, a hydroxyl group-containing epoxy compound such as glycidol, Examples include hydroxyl group-containing oxetane compounds such as oxetane alcohol.

  Other examples include oligomer-type monoalcohols such as one-end methoxylated polyethylene glycol, one-end methoxylated polypropylene glycol, and caprolactone addition polymer using monoalcohol as an initiator.

  In the present invention, when these monoalcohol compounds are used, since the isocyanate group of the resulting carboxyl group-containing urethane prepolymer (a) can be sealed, the low molecular weight carboxyl group-containing urethane prepolymer (a) intentionally. Can be suitably used when molecular weight adjustment is required, such as when synthesizing. Moreover, when using the hydroxyl-containing compound which has functional groups other than a hydroxyl group, since a functional group other than a hydroxyl group can be introduce | transduced into the terminal of a carboxyl group-containing urethane prepolymer (a), a carboxyl group-containing urethane prepolymer ( It can be suitably used when modification of the end of a) is required. In the present invention, in consideration of hydroxyl reactivity and polymerization control, lauryl alcohol, stearyl alcohol, cyclohexanol, 12-hydroxystearic acid, glycidol, 2-hydroxyethyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, etc. Is preferably used.

Examples of the diol compound (h2) having two hydroxyl groups in the molecule and having no carboxyl group and having a molecular weight or weight average molecular weight of 50 to 499 include ethylene glycol, diethylene glycol, triethylene glycol, and tetraethylene. Glycol, propylene glycol, dipropylene glycol, butylene glycol, 1,3-butanediol, 1,4-butanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 1, Aliphatic diols such as 9-nonanediol, hydrogenated bisphenol A, 1,4-cyclohexanedimethanol and spiroglycol;
Aromatic diols such as hydroquinone, 1,3-dihydroxybenzene, 1,2-dihydroxybenzene, bisphenol, bisphenoxyethanol fluorene, bisphenol fluorene, biscresol fluorene;
N, N-bis (2-hydroxypropyl) aniline, N, N-bis (2-hydroxyethyl) aniline, N, N-bis (2-hydroxyethyl) methylamine, N, N-bis (2-hydroxyethyl) ) Propylamine, N, N-bis (2-hydroxyethyl) butylamine, N, N-bis (2-hydroxyethyl) hexylamine, N, N-bis (2-hydroxyethyl) octylamine, N, N-bis Tertiary amino group-containing diol compounds such as (2-hydroxyethyl) benzylamine and N, N-bis (2-hydroxyethyl) cyclohexylamine;
Other examples include sulfur atom-containing diols and bromine atom-containing diols. In the present invention, these diol compounds (h2) may be used alone or in combination. In the present invention, by using a tertiary amino group-containing diol compound such as N, N-bis (2-hydroxypropyl) aniline, the cohesive force of the coating film is increased, and it is more resistant while maintaining flexibility. It is preferable because a tough coating film having excellent resistance can be formed.

  Examples of the polyhydric alcohol compound (h3) having three or more hydroxyl groups in the molecule and having a weight average molecular weight of 50 to 499 include trimethylolethane, polytrimethylolethane, trimethylolpropane, and polytrimethylolpropane. Pentaerythritol, polypentaerythritol, sorbitol, mannitol, arabitol, xylitol, galactitol, glycerin and the like. In the present invention, when these polyhydric alcohol compounds (h3) are used, since a part of the resulting carboxyl group-containing urethane prepolymer (a) can be branched, the crosslinking density of the cured film after photocuring is increased. Various physical properties of the cured film can be improved. Therefore, in the present invention, it may be used as necessary for the purpose of further improving various physical properties of the cured film. Among these polyhydric alcohol compounds (h3), it is preferable to use trimethylolpropane or pentaerythritol in terms of reaction control.

As the “isocyanate compound (i) having one or more isocyanate groups in the molecule” used in the present invention, specifically, as a monofunctional isocyanate having one isocyanate group in one molecule, ) Acryloyloxyethyl isocyanate, 1,1-bis [(meth) acryloyloxymethyl] ethyl isocyanate, vinyl isocyanate, allyl isocyanate, (meth) acryloyl isocyanate, isopropenyl-α, α-dimethylbenzyl isocyanate and the like.
In addition, 1,6-diisocyanatohexane, isophorone diisocyanate, 4,4′-diphenylmethane diisocyanate, polymeric diphenylmethane diisocyanate, xylylene diisocyanate, tolylene 2,4-diisocyanate, toluene diisocyanate, 2,4-diisocyanic acid Toluene, hexamethylene diisocyanate, 4-methyl-M-phenylene diisocyanate, naphthylene diisocyanate, paraphenylene diisocyanate, tetramethylxylylene diisocyanate, cyclohexylmethane diisocyanate, hydrogenated xylylene diisocyanate, cyclohexyl diisocyanate, tolidine diisocyanate, 2,2 , 4-Trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate Nitrate, M-tetramethylxylylene diisocyanate, p-tetramethylxylylene diisocyanate, diisocyanate ester compounds such as dimer acid diisocyanate and hydroxyl group, carboxyl group and amide group-containing vinyl monomers are used in equimolar amounts. be able to.

  Examples of the polyfunctional isocyanate having 3 or more isocyanate groups in one molecule include aliphatic polyisocyanates such as aromatic polyisocyanates and lysine triisocyanates, araliphatic polyisocyanates, and alicyclic polyisocyanates. And a trimethylolpropane adduct of diisocyanate (g) described above, a burette reacted with water, and a trimer having an isocyanurate ring.

  In the present invention, when a hydroxyl group remains at the terminal of the carboxyl group-containing urethane prepolymer (a) and it is desired to reduce the hydroxyl group, a monofunctional isocyanate having one isocyanate group in one molecule may be used. preferable. When the carboxyl group-containing urethane prepolymer (a) is branched for the purpose of improving the solvent resistance and hardness of the cured coating obtained by photocuring from the photosensitive flame retardant resin composition according to the present invention, 1 It is preferable to use a polyfunctional isocyanate having three or more isocyanate groups in the molecule. In the present invention, these isocyanate compounds can be appropriately selected and used according to the purpose and application, and may be used alone or in combination.

  Furthermore, in the present invention, when the carboxyl group-containing urethane prepolymer (a) is synthesized, an amine compound (j) can be reacted as a desired component. The amine compound (j) in the present invention refers to a compound having at least one primary or secondary amino group in the molecule.

  Examples of the amine compound (j) of the present invention include monoamine compounds such as propylamine, hexylamine, cyclohexylamine, benzylamine, 2-ethylhexylamine, octylamine, dodecylamine, and aniline, ethylenediamine, propylenediamine, and trimethylene. Diamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, triethylenetetramine, diethylenetriamine, triaminopropane, 2,2,4-trimethylhexamethylenediamine, tolylenediamine, hydrazine, piperazine and other aliphatic polyamines, isophoronediamine And cycloaliphatic polyamines such as dicyclohexylmethane-4,4′-diamine, and aromatic polyamines such as phenylenediamine and xylylenediamine. .

  Also, diamine compounds such as both-end amino group-modified polyethylene oxide, both-end amino group-modified polypropylene oxide, polysilicone diamine, and polybutadiene diamine, one-end amino group-modified polyethylene oxide, one-end amino group-modified polypropylene oxide, polysilicon monoamine, Examples thereof include monoamine compounds such as polybutadiene monoamine, and polymer type polyamine compounds such as polyethyleneimine and polyallylamine.

  Also, as the amine compound (j), the primary amino group in the compound having a primary amino group is modified to a secondary amino group by Michael addition reaction with the (meth) acrylate group of the (meth) acrylate group-containing compound. The amine compound obtained by doing this is mentioned. When such a compound is used, a polar functional group can be introduced into the carboxyl group-containing urethane prepolymer (a) by selecting an appropriate (meth) acrylate group-containing compound. For example, the acrylate group of 4-hydroxybutyl acrylate is Michael-added to the primary amino group of isophoronediamine to synthesize a diamine having a secondary amino group and used as a raw material for the urethane resin of the present invention. Hydroxyl groups can be introduced therein.

  In addition, as the amine compound (j) of the present invention, an amine compound having a functional group other than an amino group can also be used. For example, 2-hydroxyethylethylenediamine, N- (2-hydroxyethyl) propylenediamine, (2-hydroxyethylpropylene) diamine, (di-2-hydroxyethylethylene) diamine, (di-2-hydroxyethylpropylene) diamine, Diamines having a hydroxyl group such as (2-hydroxypropylethylene) diamine, (di-2-hydroxypropylethylene) diamine, dimer amine obtained by converting the carboxyl group of dimer acid into an amino group, and polyoxyl having propoxyamine at both ends. Examples thereof include oxyalkylene glycol diamine.

  In the present invention, these amine compounds (j) may be used alone or in combination, and a monoamine, a diamine, or a polyamine is appropriately selected or used depending on the purpose or application. be able to.

  For example, when synthesizing the carboxyl group-containing urethane prepolymer (a), by using a monoamine compound in combination, the amount of residual isocyanate groups can be reduced and the reaction can be stopped, so that the molecular weight can be easily controlled. Moreover, by using a diamine compound, it becomes possible to extend a polymer chain, and a high molecular weight polymer can be obtained. Furthermore, by using a polyamine compound, the polymer chain can be branched and finally the cohesive strength and resistance of the cured coating can be improved.

  As a method of reacting the amine compound (j), a method of reacting with the diisocyanate compound (g) after charging simultaneously with other raw materials such as the polymer polyol (e), or a method of reacting with the diisocyanate compound (g) by the above method. Thereafter, a method of further reacting with the isocyanate compound (i), or synthesizing an isocyanate-terminated urethane chain in advance, and adding or dropping the amine compound (j) to extend the chain, thereby adding a carboxyl group containing a urea bond. Examples thereof include a method for obtaining a group-containing urethane prepolymer (a). In the present invention, when the amine compound (j) is reacted in this manner, the cohesive force of the resulting urethane resin (A) is improved, and a coating film with more excellent heat resistance and durability can be formed. It is preferred to use j).

  In the present invention, the synthesis conditions of the carboxyl group-containing urethane prepolymer (a) are not particularly limited, and can be performed under known conditions.

For example, a polymer polyol (e), a carboxylic acid compound (f), and a solvent are charged into a flask and dissolved uniformly by heating and stirring at 20 to 120 ° C. in a nitrogen stream, and then the diisocyanate compound (g) is added. Then, the carboxyl group-containing urethane prepolymer (a) can be obtained by heating at 50 to 150 ° C. with stirring. In this case, a urethanization catalyst such as an organic tin compound or a tertiary amino group-containing compound may be used as necessary.
In the reaction, it is preferable to charge the hydroxyl group-containing compound (h) together with the solvent, and it is also preferable to add the isocyanate compound (i) together with the diisocyanate compound (g).

  Next, the hydroxyl group-containing urethane prepolymer (c) is synthesized by reacting the carboxyl group-containing urethane prepolymer (a) with the compound (b) having an epoxy group or oxetane group and an ethylenically unsaturated group.

  In the present invention, the proportion of the carboxyl group-containing urethane prepolymer (a) and the compound (b) having an epoxy group or oxetane group and an ethylenically unsaturated group is reacted as described above. The epoxy group or oxetane group in the compound (b) having an epoxy group or oxetane group and an ethylenically unsaturated group is used in an amount of 0.1 mol to 1.0 mol based on 1 mol of the carboxyl group in the polymer (a). It is preferable to make it react in a ratio, and 0.3 mol-0.95 mol are more preferable. Here, with respect to the carboxyl group in the carboxyl group-containing urethane prepolymer (a), the ratio of reacting the epoxy group or oxetane group in the compound (b) having an epoxy group or oxetane group and an ethylenically unsaturated group, When the amount is less than 0.1 mol, the amount of unsaturated groups in the finally obtained urethane resin (A) decreases, so that the photosensitive flame retardant resin composition has insufficient photosensitivity and fine phosphinate particles. There is a risk that it may be difficult to obtain a good dispersion stability.

  The compound (b) having an epoxy group or oxetane group and an ethylenically unsaturated group used in the present invention is preferably a compound having 6 to 50 carbon atoms. Specifically, for example, glycidyl (meth) acrylate, glycidyl cinnamic acid, 4-hydroxybutyl (meth) acrylate glycidyl ether, glycidyl allyl ether, 2,3-epoxy-2-methylpropyl (meth) acrylate, (3,4 -Epoxycyclohexyl) methyl (meth) acrylate, 4-vinyl-1-cyclohexene-1,2-epoxide, 1,3-butadiene monoepoxide, oxetanyl (meth) acrylate, oxetanyl cinnamic acid. Alternatively, most of the epoxy groups of polyfunctional acrylate groups, such as pentaerythritol triacrylate, in which epichlorohydrin is reacted with the hydroxyl groups of a hydroxyl group-containing polyfunctional acrylic monomer, or the epoxy groups of phenol novolac epoxy resins are acrylated with acrylic acid. The polyfunctional acrylate group-containing monoepoxide and the carboxyl group of the carboxyl group-containing polyfunctional acrylic monomer that have one epoxy group left on average in one molecule obtained by modifying the polymer into two or more epoxy groups in the molecule Examples thereof include a polyfunctional acrylate group-containing monoepoxide obtained by reacting a part of the epoxy group of a compound having the same. Among these, glycidyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate glycidyl ether, and the like are rich in reactivity with the carboxyl group in the carboxyl group-containing urethane prepolymer (a) in the present invention. Since the photosensitivity of the photosensitive resin composition obtained is very excellent, it is especially preferable. In the present invention, the compound (b) having an epoxy group or oxetane group and an ethylenically unsaturated group may be used alone or in combination.

  The reaction conditions for reacting the carboxyl group in the carboxyl group-containing urethane prepolymer (a) with the epoxy group or oxetane group in the compound (b) having an epoxy group or oxetane group and an ethylenically unsaturated group are as follows: It is not specifically limited, It can carry out on well-known conditions. For example, a carboxyl group-containing urethane prepolymer (a), a compound (b) having an epoxy group or oxetane group and an ethylenically unsaturated group, and a solvent are charged in a flask and heated at 50 to 150 ° C. with stirring in an oxygen stream. By doing so, a hydroxyl group-containing urethane prepolymer (c) is obtained. At this time, if necessary, a tertiary amino group-containing compound such as triethylamine or dimethylbenzylamine is added as a catalyst. Furthermore, it is also preferable to add a polymerization inhibitor of an ethylenically unsaturated group such as hydroquinone or methoquinone. The addition amount of the catalyst is 0.1 to 10% by weight with respect to the total of (a) and (b), and the addition amount of the inhibitor is 0.05 to 10% by weight. preferable.

  Furthermore, in this invention, the said hydroxyl-containing urethane prepolymer (c) and polybasic acid anhydride (d) are made to react, and the urethane resin (A) which has a carboxyl group and an ethylenically unsaturated group is manufactured. To do. The polybasic acid anhydride (d) used in the present invention is a compound having an acid anhydride group, and by reacting the acid anhydride group with a hydroxyl group in the hydroxyl group-containing urethane prepolymer (c), A urethane resin (A) is obtained.

  In the present invention, the ratio of reacting the hydroxyl group-containing urethane prepolymer (c) with the polybasic acid anhydride (d) is such that the polybasic acid anhydride is 1 mol of the hydroxyl group in the hydroxyl group-containing urethane prepolymer (c). The acid anhydride group in (d) is preferably reacted at a ratio of 0.1 mol to 1.0 mol. When the ratio of reacting the acid anhydride group in the polybasic acid anhydride (d) with respect to 1 mol of the hydroxyl group in the hydroxyl group-containing urethane prepolymer (c) is less than 0.1 mol, curability and developability The ratio of introducing a carboxyl group that is excellent in the reduction is reduced, and the developability may be insufficient.

  The polybasic acid anhydride (d) used in the present invention is preferably a compound having 1 or 2 carboxylic acid anhydride groups in the molecule and having 4 to 50 carbon atoms. Specifically, for example, phthalic anhydride, trimellitic anhydride, methyltetrahydrophthalic anhydride, methylhymic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methylpentahydrophthalic anhydride, methyltrihydrophthalic anhydride , A compound having an alicyclic structure such as trialkyltetrahydrophthalic anhydride, methylcyclohexene dicarboxylic acid anhydride, het acid anhydride, tetrabromophthalic anhydride, or an aromatic ring structure. Other polybasic acid anhydrides (d) include succinic anhydride, maleic anhydride, glutaric anhydride, butyl succinic anhydride, hexyl succinic anhydride, octyl succinic anhydride, dodecyl succinic anhydride, butyl maleic acid. Acid anhydride, pentylmaleic acid anhydride, hexylmaleic acid anhydride, octylmaleic acid anhydride, decylmaleic acid anhydride, dodecylmaleic acid anhydride, butylglutamic acid anhydride, hexylglutamic acid anhydride, heptylglutamic acid anhydride, octyl Examples include glutamic anhydride, decylglutamic anhydride, dodecylglutamic anhydride, and the like. Among these, succinic anhydride, tetrahydrophthalic anhydride, and the like are particularly preferable because the photosensitive resin composition obtained in the present invention has excellent developability, pattern formability, and coating film resistance. Polybasic acid anhydrides (d) may be used alone or in combination.

  The reaction conditions for reacting the hydroxyl group in the hydroxyl group-containing urethane prepolymer (c) with the acid anhydride group in the polybasic acid anhydride (d) are not particularly limited, and may be performed under known conditions. it can. For example, a urethane resin (A) is obtained by charging a flask with a hydroxyl group-containing urethane prepolymer (c), a polybasic acid anhydride (d), and a solvent, and heating at 50 to 150 ° C. with stirring in an oxygen stream. It is done. At this time, it is preferable to add a tertiary amino group-containing compound such as triethylamine or dimethylbenzylamine as a catalyst. In this case, the total of the hydroxyl group-containing urethane prepolymer (c) and the polybasic acid anhydride (d) is added. It is preferable to add in the range of 0.1 to 10% by weight.

  The acid value of the urethane resin (A) having a carboxyl group and an ethylenically unsaturated group of the present invention is preferably 10 to 150 mgKOH / g, more preferably 40 to 100 mgKOH / g. When the acid value is less than 10 mg KOH / g, sufficient developability may be difficult to obtain. For example, the film may remain as a residue in a portion where the film is dissolved and removed during development. In addition, when the acid value exceeds 150 mgKOH / g, the solubility of the coating film in the developer is increased, and even the portion that is desired to be photocured and left as a pattern is dissolved, and the pattern shape may be deteriorated. The probability that the carboxylic acid of the urethane resin (A) coordinates to the salt site of the phosphinic acid salt (B) is increased, and the viscosity of the solution may increase during the dispersion process or the subsequent process, There is a risk of preventing the phosphinate (B) from being refined. The acid value is measured by potentiometric titration according to JIS K 2501.

  The ethylenically unsaturated group equivalent of the urethane resin (A) having a carboxyl group and an ethylenically unsaturated group of the present invention is preferably 200 to 3000 g / eq, more preferably 300 to 2000 g / eq. . When the ethylenically unsaturated group equivalent is less than 200 g / eq, the photosensitivity may be too high, and even the part to be removed by dissolving the film during development is cured with light, and a good pattern shape is obtained. There may not be. When the ethylenically unsaturated group equivalent exceeds 3000 g / eq, the photosensitivity may be too low, the portion to be photocured may not be sufficiently cured, and the pattern dissolves during development, thereby obtaining a good pattern shape. Otherwise, the unsaturated group adsorbed on the surface of the phosphinate (B) particles is reduced, so that the fine dispersion stability of the phosphinate (B) particles may be insufficient.

  The “ethylenically unsaturated group equivalent” as used in the present invention is a theoretical value calculated from the weight of raw materials used during the synthesis of the resin, and the weight of the resin is the ethylenically unsaturated group present in the resin. It is divided by the number of groups and corresponds to the weight of the resin per mole of ethylenically unsaturated groups, that is, the reciprocal of the ethylenically unsaturated group concentration.

  The weight average molecular weight of the urethane resin (A) having a carboxyl group and an ethylenically unsaturated group of the present invention is preferably 1000 to 100,000, more preferably 3000 to 60000. When the weight average molecular weight is less than 1000, the cured film may have insufficient solder heat resistance and flexibility. On the other hand, when the weight average molecular weight exceeds 100,000, the developability may be deteriorated although the solder heat resistance is excellent. Moreover, there exists a possibility that the viscosity of a photosensitive flame-retardant resin composition may increase, and coating suitability may fall.

The phosphinic acid salt (B) of the present invention will be described.
The phosphinic acid salt (B) of the present invention is preferably represented by the following general formula (1).
General formula (1)

(R1 and R2 are the same or different and represent a linear or branched alkyl group having 1 to 6 carbon atoms or an aryl group, and M represents Mg, Ca, Al, Sb, Sn, Ge, Ti. , Zn, Fe, Zr, Ce, Bi, Sr, Mn, Li, Na, and at least one metal selected from the group consisting of K, and n is an integer of 1 to 4.
Examples of commercially available products include aluminum phosphinates manufactured by Clariant Japan Co., Ltd .: Exolit OP930, Exolit OP935, Exolit OP1230, Exolit OP1240, and Exolit OP1312.

The phosphinic acid salt (B) is excellent as a flame retardant for electronic materials because it is excellent in hydrolysis resistance and excellent in electrical insulation, and has high phosphorus concentration per molecular weight, so that it exhibits flame retardancy with a small addition amount. ing. However, since the volume average particle diameter of the conventional phosphinate is generally 2 to 3 μm (for example, Exolit OP935 Clariant Japan Co., Ltd.), the primary particle diameter is used as, for example, a photosensitive flame retardant resin composition for flexible printed circuit boards. In such a case, it is difficult to achieve the high-definition pattern forming property, flexibility, and bendability required as physical properties required for the material. Therefore, it is preferable to disperse the phosphinic acid salt in the photo solder resist composition with a smaller nano-level particle diameter. By refining the volume average particle diameter of the phosphinate, a higher-definition pattern can be formed.
For this purpose, the phosphinic acid salt (B) preferably has a volume average particle size of 0.1 to 1 μm, more preferably 0.1 to 0.5 μm. Examples of the miniaturization method include a dispersion method using a three-roll mill, a two-roll mill, a sand mill, a kneader, an attritor or the like.

  On the other hand, the urethane resin (A) is excellent in flexibility and bendability, and is excellent as an adhesive used for flexible printed circuit boards and the like and as a main resin for a protective layer. However, when a urethane resin having only a carboxyl group is used, for example, a carboxyl group is coordinated to the aluminum salt of aluminum phosphinate to form a crosslink, and the viscosity of the coating liquid increases or gels in each step such as dispersion and blending. There is a risk of becoming a cause. In addition, fine dispersion may be difficult due to increase in viscosity.

The amount of the phosphinate (B) is preferably 5 to 50 parts by weight, more preferably 10 to 40 parts by weight with respect to 100 parts by weight of the urethane resin (A). If the blending amount is less than 5 parts by weight, sufficient flame retardancy may not be obtained. On the other hand, if the blending amount exceeds 50 parts by weight, physical properties such as flexibility, bendability, electrical insulation and solder heat resistance may be lowered. Further, a non-halogen flame retardant (C) other than the phosphinate (B) may be used in combination to such an extent that the physical properties are not affected.
Examples of the non-halogen flame retardant (C) include melamine phosphate, melamine polyphosphate, guanidine phosphate, guanidine polyphosphate, ammonium phosphate, ammonium polyphosphate, ammonium amidophosphate, ammonium amidophosphate, carbamate phosphate, polyphosphoric acid Phosphate compounds such as phosphate compounds such as carbamate, polyphosphate compounds, red phosphorus, organophosphate compounds, phosphazene compounds, phosphonate compounds, phosphine oxide compounds, phosphaphenanthrene compounds, phospholane compounds, phosphoramide compounds Nitrogen compounds such as flame retardants, melamine, melam, triazine compounds such as melamine cyanurate, cyanuric acid compounds, isocyanuric acid compounds, triazole compounds, tetrazole compounds, diazo compounds, urea Flame retardants, silicon flame retardants such as silicone compounds and silane compounds, metal hydroxides such as aluminum hydroxide, magnesium hydroxide, zirconium hydroxide, barium hydroxide, calcium hydroxide, tin oxide, aluminum oxide, magnesium oxide, oxidation Examples thereof include inorganic flame retardants such as zirconium, zinc oxide, molybdenum oxide, antimony oxide, nickel oxide, zinc carbonate, magnesium carbonate, calcium carbonate, barium carbonate, zinc borate, and hydrated glass. Among them, use of a phosphazene compound, a melamine polyphosphate, a phosphaphenanthrene compound, a melamine cyanurate, etc. that can reduce the deterioration of various physical properties and enhance the flame retardant effect by using in combination with the phosphinate (B) of the present invention Is preferred. In the present invention, these non-halogen flame retardants (C) may be used alone or in combination of two or more.

  The photosensitive flame retardant resin composition of the present invention preferably also contains a photopolymerization initiator (D). The photopolymerization initiator is not particularly limited as long as it has a function capable of initiating radical polymerization by photoexcitation. For example, a monocarbonyl compound, dicarbonyl compound, acetophenone compound, benzoin ether compound, acylphosphine oxide compound, aminocarbonyl A compound etc. can be used. Although there is no restriction | limiting in the usage-amount of a photoinitiator (D), It is preferable to add in the range of 1-20 weight part with respect to 100 weight part of urethane resins (A). Moreover, a well-known organic amine can also be added as a sensitizer.

The photosensitive flame retardant resin composition of the present invention preferably further contains a photosensitive ethylenically unsaturated group-containing compound (E). The photosensitive ethylenically unsaturated group-containing compound (E) is used for the purpose of adjusting the photosensitivity of the photosensitive flame retardant resin composition, and has an ethylenically unsaturated double bond in the molecule. In the present invention, a photosensitive compound other than the “urethane resin (A) having a carboxyl group and an ethylenically unsaturated group” can be used as the photosensitive ethylenically unsaturated group-containing compound (E).
As long as the photosensitive ethylenically unsaturated group-containing compound (E) has an ethylenically unsaturated double bond in the molecule and is not included in the definition of the “urethane resin (A)” of the present invention, Although not particularly limited, for example, (meth) acrylic acid alkyl ester, (meth) acrylic acid alkylene glycol ester, compound having a carboxyl group and an ethylenically unsaturated group [however, included in the definition of the urethane resin (A) And a (meth) acrylate compound having a hydroxyl group, a nitrogen-containing (meth) acrylate compound, and the like.

  The photosensitive ethylenically unsaturated group-containing compound (E) is preferably used in an amount of 0.1 to 300 parts by weight, and 0.5 to 200 parts by weight, based on 100 parts by weight of the urethane resin (A). More preferably, it is more preferably used in an amount of 5 to 100 parts by weight. If the amount is less than 0.1 part by weight, the photosensitivity of the photosensitive resin composition may be insufficient. If the amount exceeds 300 parts by weight, the flexibility may be insufficient.

  The photosensitive flame retardant resin composition of the present invention may further contain a thermosetting compound (F) and a thermosetting aid (G).

  If the thermosetting compound (F) has two or more functional groups capable of reacting with the functional groups (carboxyl group and hydroxyl group) contained in the urethane resin (A) having a carboxyl group and an ethylenically unsaturated group. It is not particularly limited.

Examples of the compound having at least two functional groups capable of reacting with hydroxyl groups in the thermosetting compound (F) include polyisocyanate compounds, amino resins, phenol resins, and polyfunctional polycarboxylic acid anhydrides.
As the compound having at least two functional groups capable of reacting with a carboxyl group in the thermosetting component (F), compounds having two or more epoxy groups or oxetane groups, polyfunctional vinyl ether compounds, high molecular weight polycarbodiimides, Examples include aziridine compounds. Among these, a compound having two or more epoxy groups or oxetane groups is particularly preferable in view of the curing speed and the durability of the cured product.

  These thermosetting compounds (F) may be used alone or in combination. The amount of the thermosetting compound (F) used may be determined in consideration of the application of the photosensitive flame retardant resin composition, and is not particularly limited. However, the carboxyl group and the ethylenically unsaturated group may be used. 0.1-100 weight part is preferable with respect to 100 weight part of urethane resin (A) to have, and 0.5 weight part-80 weight part is more preferable. Thereby, since the crosslinking density of the cured film formed from the photosensitive flame retardant resin composition can be appropriately adjusted, various physical properties of the cured film can be further improved. When the usage-amount of a thermosetting compound (F) is less than 0.1 weight part, there exists a possibility that the crosslinking density of a cured film may become low and cohesion force and durability may become insufficient. On the other hand, if the amount used exceeds 100 parts by weight, the cross-linking density of the cured film becomes excessive, the flexibility and flexibility of the cured product are lowered, and the printed wiring board may be warped.

Next, the thermosetting aid (G) will be described. The thermosetting aid (G) referred to in the present invention represents a compound that contributes directly or catalytically to the curing reaction during thermosetting.
The thermosetting aid (G) is appropriately selected depending on the type of the thermosetting compound (F) to be used.
In the present invention, when an epoxy compound is used as the thermosetting compound (F), the use of dicyandiamide, carboxylic acid hydrazide, imidazoles, or diazabicyclo compounds as the thermosetting aid (G) is more efficient. It is preferable because the curing reaction proceeds and the coating film has excellent resistance.

  Moreover, in this invention, a thermosetting adjuvant (G) is used within the range of 0.1-10 weight part with respect to 100 weight part of urethane resin (A) which has a carboxyl group and an ethylenically unsaturated group. It is preferable to make it within the range of 0.5 to 8 parts by weight. If the amount used is less than 0.1 parts by weight, the cohesive strength and durability of the cured product may be insufficient. On the other hand, when the amount used is more than 10 parts by weight, an excessive thermosetting auxiliary agent remains in the cured product, which may deteriorate various physical properties of the cured product, such as bleeding and deterioration of insulating properties.

  The photosensitive flame retardant resin composition of the present invention may contain the following resins as necessary. Specific examples include acrylic resins, polyester resins, urethane resins, urea resins, urethane urea resins, epoxy resins, polyamide resins, and polyimide resins. From the viewpoint of developability, those containing a carboxyl group are preferred, and those having excellent compatibility with the urethane resin (A) having a carboxyl group and an ethylenically unsaturated group are preferred.

  In addition to the above, the photosensitive flame retardant resin composition of the present invention includes, as an optional component, a solvent, a dye, a pigment, an antioxidant, a polymerization inhibitor, a leveling agent, a humectant, a viscosity as long as the object of the present invention is not impaired. An adjuster, preservative, antibacterial agent, antistatic agent, antiblocking agent, ultraviolet absorber, infrared absorber, electromagnetic wave shielding agent, filler and the like can be added.

The photosensitive flame retardant resin composition of the present invention can be cured by light to form a cured product, and as the light, ultraviolet light or visible light having a wavelength of 400 to 500 nm can be used. As the light source, for example, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a metal halide lamp, a gallium lamp, a xenon lamp, a carbon arc lamp, or the like can be used. The active energy dose to be irradiated, can be set appropriately in the range of 5~2000mJ / cm ^2, it is preferably in the range on the easy of 50~1000mJ / cm ² management process. Further, it is possible to use these light and heat by electron beam, infrared ray, far infrared ray, hot air, high-frequency heating and the like.

  As a base material used in order to form hardened | cured material from the photosensitive flame-retardant resin composition of this invention, a metal, ceramics, glass, a plastic, wood, slate etc. can be used, for example. Examples of the plastic include polyester, polyolefin, polycarbonate, polystyrene, polymethyl methacrylate, triacetyl cellulose resin, ABS resin, AS resin, polyamide, epoxy resin, and melamine resin. Moreover, as a shape of a base material, although a film sheet, a plate-shaped panel, a lens shape, a disk shape, and a fiber-like thing are mentioned, it does not restrict | limit in particular.

  Since the photosensitive flame retardant resin composition of the present invention has a carboxyl group, it is characterized by excellent alkali developability. Therefore, it is preferably used for applications requiring a cured product forming process including photocuring, alkali development, and post-cure. In addition, the cured product has excellent solder heat resistance and coating film resistance, as well as excellent flexibility and flexibility, so it is especially hardened for solder resist inks for flexible printed wiring boards and photosensitive coverlay films. It can be suitably used as a film.

  When used as a photo solder resist as a usage mode of the photosensitive flame retardant resin composition of the present invention, it is preferably used as a liquid resist ink containing a solvent or a dry film type resist obtained by previously drying the solvent.

  For example, when used as a liquid resist ink, the photosensitive flame retardant resin composition of the present invention may be photocured after coating the substrate and volatilizing the solvent by natural or forced drying. Moreover, although it is preferable to carry out photocuring after natural or forced drying following coating, drying is not necessary when a solvent is not included. In the case of a liquid resist ink, it is preferable that the solvent does not volatilize for handling until the application to the substrate is completed. Therefore, the solvent to be used preferably has a high boiling point. Specifically, for example, carbitol acetate, methoxypropyl acetate, cyclohexanone, diisobutyl ketone and the like are particularly preferable. In addition, when used as a liquid resist ink, in consideration of storage stability and handling, a curing agent [a thermosetting compound (F) and a thermosetting auxiliary agent (G)] is separately stored in advance and coated. It is also preferable to use it as a two-component type in which a curing agent is mixed before use.

  On the other hand, when using as a dry film type resist, first, after applying the photosensitive flame retardant resin composition to the release film, if it contains a solvent, it is dried to prepare a dry film type resist. In this case, unlike the above-described liquid resist ink, it is necessary to dry the solvent completely in a short time, and therefore a solvent having a low boiling point is preferable. For example, it is particularly preferable to use methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, butyl acetate, tetrahydrofuran, toluene, isopropyl alcohol, or the like. The prepared dry film is bonded to, for example, a copper circuit formed on polyimide by a laminator or a vacuum laminator. After this bonding step, photocuring is performed. However, photocuring may be performed via a release film, or photocuring may be performed by bringing a development pattern into contact after peeling the release film. When photocuring is performed by bringing the development pattern into contact, if the dry film has tack, the development pattern may be contaminated. Therefore, it is preferable that the dry film resist has little dry coating tack.

  Furthermore, the photosensitive flame retardant resin composition of the present invention forms a pattern by developing after photocuring, and forms a cured film having excellent resistance by thermosetting as post-cure. The post cure is preferably 30 to 2 hours at 100 to 200 ° C. Further, in order to further improve the resistance of the cured film, it is possible to irradiate with light as necessary after post-curing. By irradiating with light after post-cure, solder heat resistance and the like can be further improved.

  The photosensitive flame retardant resin composition of the present invention is preferably used for applications such as a printed wiring board, but is flexible and has excellent bending resistance. It is also preferable to use it for substrates.

  The present invention will be described more specifically with reference to the following examples. However, the following examples do not limit the scope of rights of the present invention. In the examples, “part” represents “part by weight”, “%” represents “% by weight”, and “Mw” represents a weight average molecular weight.

[Production Example 1]
156 parts of polytetramethylene glycol (PTG1000SN: manufactured by Hodogaya Chemical Co., Ltd .: hydroxyl value = 110 mgKOH / g, Mw = 1020) in a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, inlet tube, thermometer Then, 129 parts of dimethylolbutanoic acid (manufactured by Nippon Kasei Co., Ltd.) and 375 parts of cyclohexanone as a solvent were charged, and the mixture was heated to 60 ° C. with stirring in a nitrogen stream, and dissolved uniformly. Subsequently, 215 parts of isophorone diisocyanate was added to the flask and stirred at 90 ° C. for 8 hours to carry out a urethanization reaction. A small amount of sampling was performed to obtain a carboxyl group-containing urethane prepolymer solution having a polystyrene-equivalent weight average molecular weight of 13000 and an actually measured polymer non-volatile acid value of 98 mgKOH / g.

  Next, nitrogen from the nitrogen inlet tube of this flask was stopped, switching to introduction of dry air, and 111 parts of glycidyl methacrylate, 6 parts of dimethylbenzylamine, and 0.3 part of hydroquinone as a polymerization inhibitor were added while stirring. The reaction was continued for 8 hours at 90 ° C. After completion of the reaction, a small amount of sampling was performed to obtain a hydroxyl group-containing urethane prepolymer solution having a polystyrene-reduced weight average molecular weight of 14800 and an actually measured acid non-volatile content of 8 mgKOH / g.

  Next, 63 parts of succinic anhydride was added to the flask, and the reaction was further continued for 6 hours at 90 ° C. in a dry air atmosphere. After confirming that the absorption of the acid anhydride group disappeared by FT-IR measurement, it was cooled to room temperature. Next, cyclohexanone was added to this solution to adjust the nonvolatile content to 50.0%. The non-volatile ethylenically unsaturated group equivalent of the urethane resin (A-1) having a carboxyl group and an ethylenically unsaturated group prepared by this production example is 863 g / eq, and the weight average molecular weight in terms of polystyrene is 15400. The actually measured acid value was 73 mgKOH / g.

The measurement conditions for GPC are as follows.
<Measurement of weight average molecular weight (Mw)>
For measurement of Mw, GPC (gel permeation chromatography) “HPC-8020” manufactured by Tosoh Corporation was used. GPC is liquid chromatography that separates and quantifies substances dissolved in a solvent (THF; tetrahydrofuran) based on the difference in molecular size. In the measurement of the present invention, “LF-604” (manufactured by Showa Denko KK: GPC column for rapid analysis: 6MMID × 150MM size) is connected in series to the column, the flow rate is 0.6 ML / MIN, the column temperature. It carried out on the conditions of 40 degreeC, and the determination of the weight average molecular weight (Mw) was performed in polystyrene conversion.

[Production Example 2]
4 parts of polytetramethylene glycol (PTG1000SN: manufactured by Hodogaya Chemical Co., Ltd .: hydroxyl value = 110 mgKOH / g, Mw = 1020) was added to a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, inlet tube, and thermometer. In addition, 201 parts of dimethylolbutanoic acid (manufactured by Nippon Kasei Co., Ltd.) and 375 parts of cyclohexanone as a solvent were charged, and the mixture was heated to 60 ° C. with stirring under a nitrogen stream and dissolved uniformly. Subsequently, 296 parts of isophorone diisocyanate was added to the flask and stirred at 90 ° C. for 8 hours to carry out a urethanization reaction. After completion of the reaction, a small amount of sampling was performed to obtain a carboxyl group-containing urethane prepolymer solution having a polystyrene-equivalent weight average molecular weight of 8900 and an actually measured polymer nonvolatile acid value of 152 mgKOH / g.

  Next, nitrogen from the nitrogen inlet tube of this flask was stopped, switched to introduction of dry air, 193 parts of glycidyl methacrylate, 7 parts of dimethylbenzylamine and 0.4 part of hydroquinone as a polymerization inhibitor were added while stirring. The reaction was continued for 8 hours at 90 ° C. After completion of the reaction, a small amount of sampling was performed to obtain a hydroxyl group-containing urethane prepolymer solution having a polystyrene-equivalent weight average molecular weight of 9600 and an actually measured acid non-volatile content of 1 mgKOH / g.

  Next, 136 parts of succinic anhydride was added to the flask, and the reaction was further continued for 6 hours at 90 ° C. in a dry air atmosphere. After confirming that the absorption of the acid anhydride group disappeared by FT-IR measurement, it was cooled to room temperature. Next, cyclohexanone was added to this solution to adjust the nonvolatile content to 50.0%. The urethane resin (A-2) having a carboxyl group and an ethylenically unsaturated group prepared by this production example has an ethylenically unsaturated group equivalent of volatile content of 611 g / eq, and a polystyrene-equivalent weight average molecular weight of 11020. The actually measured acid value was 92 mgKOH / g.

[Production Example 3]
In a four-necked flask equipped with a stirrer, a reflux condenser, a nitrogen inlet pipe, an inlet pipe, and a thermometer, 318 parts of polytetramethylene glycol (PTG1000SN: Hodogaya Chemical Co., Ltd .: hydroxyl value = 110 mgKOH / g, Mw = 1020) Then, 46 parts of dimethylolbutanoic acid (manufactured by Nippon Kasei Co., Ltd.) and 375 parts of cyclohexanone as a solvent were charged, and the temperature was raised to 60 ° C. with stirring in a nitrogen stream to dissolve the mixture uniformly. Subsequently, 136 parts of isophorone diisocyanate was added to the flask and stirred at 90 ° C. for 8 hours to carry out a urethanization reaction. After completion of the reaction, a small amount of sampling was performed to obtain a carboxyl group-containing urethane prepolymer solution having a polystyrene-equivalent weight average molecular weight of 19800 and an actually measured acid value of 35 mg KOH / g of the nonvolatile polymer content.

  Next, nitrogen from the nitrogen inlet tube of this flask was stopped, switching to introduction of dry air, 44 parts of glycidyl methacrylate, 5 parts of dimethylbenzylamine and 0.3 part of hydroquinone as a polymerization inhibitor were added while stirring. The reaction was continued for 8 hours at 90 ° C. After completion of the reaction, a small amount of sampling was performed to obtain a hydroxyl group-containing urethane prepolymer solution having a polystyrene-equivalent weight average molecular weight of 22,000 and an actually measured acid value of 3 mg KOH / g of the nonvolatile polymer content.

  Next, 31 parts of succinic anhydride was added to the flask, and the reaction was further continued for 6 hours at 90 ° C. in a dry air atmosphere. After confirming that the absorption of the acid anhydride group disappeared by FT-IR measurement, it was cooled to room temperature. Next, cyclohexanone was added to this solution to adjust the nonvolatile content to 50.0%. The non-volatile ethylenically unsaturated group equivalent of the urethane resin (A-3) having a carboxyl group and an ethylenically unsaturated group prepared by this production example is 1846 g / eq, and the weight average molecular weight in terms of polystyrene is 23100. The actually measured acid value was 30 mgKOH / g.

[Production Example 4]
In a four-necked flask equipped with a stirrer, a reflux condenser, a nitrogen inlet pipe, an inlet pipe, and a thermometer, 318 parts of polytetramethylene glycol (PTG1000SN: Hodogaya Chemical Co., Ltd .: hydroxyl value = 110 mgKOH / g, Mw = 1020) Then, 46 parts of dimethylolbutanoic acid (manufactured by Nippon Kasei Co., Ltd.) and 375 parts of cyclohexanone as a solvent were charged, and the temperature was raised to 60 ° C. with stirring in a nitrogen stream to dissolve the mixture uniformly. Subsequently, 136 parts of isophorone diisocyanate was added to the flask and stirred at 90 ° C. for 8 hours to carry out a urethanization reaction. After completion of the reaction, a small amount of sampling was performed to obtain a carboxyl group-containing urethane prepolymer solution having a polystyrene-equivalent weight average molecular weight of 19800 and an actually measured acid value of 35 mg KOH / g of the nonvolatile polymer content.

  Next, nitrogen from the nitrogen inlet tube of this flask was stopped, switching to introduction of dry air, 44 parts of glycidyl methacrylate, 5 parts of dimethylbenzylamine and 0.3 part of hydroquinone as a polymerization inhibitor were added while stirring. The reaction was continued for 8 hours at 90 ° C. After completion of the reaction, a small amount of sampling was performed to obtain a hydroxyl group-containing urethane prepolymer solution having a polystyrene-equivalent weight average molecular weight of 22,000 and an actually measured acid value of 3 mg KOH / g of the nonvolatile polymer content.

  Next, 11 parts of succinic anhydride was added to the flask, and the reaction was further continued for 6 hours at 90 ° C. in a dry air atmosphere. After confirming that the absorption of the acid anhydride group disappeared by FT-IR measurement, it was cooled to room temperature. Next, cyclohexanone was added to this solution to adjust the nonvolatile content to 50.0%. The urethane resin (A-4) having a carboxyl group and an ethylenically unsaturated group prepared according to this production example has an ethylenically unsaturated group equivalent of 1720 g / eq in non-volatile content, and a weight average molecular weight in terms of polystyrene of 20200. The actually measured acid value was 12 mgKOH / g.

[Production Example 5]
In a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, inlet tube and thermometer, 26 parts of polytetramethylene glycol (PTG1000SN: Hodogaya Chemical Co., Ltd .: hydroxyl value = 110 mgKOH / g, Mw = 1020) In addition, 387 parts of dimethylolbutanoic acid (manufactured by Nippon Kasei Co., Ltd.) and 382 parts of cyclohexanone as a solvent were charged, and the mixture was heated to 60 ° C. with stirring under a nitrogen stream, and dissolved uniformly. Subsequently, 587 parts of isophorone diisocyanate was added to the flask and stirred at 90 ° C. for 8 hours to carry out a urethanization reaction. After completion of the reaction, a small amount of sampling was performed to obtain a carboxyl group-containing urethane prepolymer solution having a polystyrene-equivalent weight average molecular weight of 9000 and an acid value of 147 mgKOH / g of the polymer nonvolatile content measured.

  Next, nitrogen from the nitrogen inlet tube of this flask was stopped, switching to introduction of dry air, 74 parts of glycidyl methacrylate, 11 parts of dimethylbenzylamine and 0.5 part of hydroquinone as a polymerization inhibitor were added while stirring. The reaction was continued for 8 hours at 90 ° C. After completion of the reaction, a small amount of sampling was performed to obtain a hydroxyl group-containing urethane prepolymer solution having a polystyrene-equivalent weight average molecular weight of 9500 and an actually measured acid value of 109 mgKOH / g of the nonvolatile polymer content.

  Next, 52 parts of succinic anhydride was added to the flask, and the reaction was further continued for 6 hours at 90 ° C. in a dry air atmosphere. After confirming that the absorption of the acid anhydride group disappeared by FT-IR measurement, it was cooled to room temperature. Next, cyclohexanone was added to this solution to adjust the nonvolatile content to 50.0%. The non-volatile ethylenically unsaturated group equivalent of the urethane resin (A-5) having a carboxyl group and an ethylenically unsaturated group prepared according to this production example is 2156 g / eq, and the weight average molecular weight in terms of polystyrene is 10800. The actually measured acid value was 140 mgKOH / g.

[Production Example 6]
In a four-necked flask equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, an inlet tube, and a thermometer, 61 parts of polytetramethylene glycol (PTG1000SN: Hodogaya Chemical Co., Ltd .: hydroxyl value = 110 mgKOH / g, Mw = 1020) , 172 parts of dimethylol butanoic acid (manufactured by Nippon Kasei Co., Ltd.) and 375 parts of cyclohexanone as a solvent were added, and the mixture was heated to 60 ° C. with stirring in a nitrogen stream and dissolved uniformly. Subsequently, 267 parts of isophorone diisocyanate was added to the flask and stirred at 90 ° C. for 8 hours to carry out a urethanization reaction. After completion of the reaction, a small amount of sampling was performed to obtain a carboxyl group-containing urethane prepolymer solution having a polystyrene-equivalent weight average molecular weight of 10300 and an actually measured acid value of 135 mgKOH / g of the nonvolatile polymer content.

Next, nitrogen from the nitrogen inlet tube of this flask was stopped, switching to introduction of dry air, 71 parts of glycidyl methacrylate, 6 parts of dimethylbenzylamine and 0.3 part of hydroquinone as a polymerization inhibitor were added while stirring. The reaction was continued for 8 hours at 90 ° C. After completion of the reaction, cyclohexanone was added to adjust the nonvolatile content to 50.0%. The urethane resin (A-6) having a carboxyl group and an ethylenically unsaturated group prepared according to this production example has an ethylenically unsaturated group equivalent of 1025 g / eq in non-volatile content, and a weight average molecular weight in terms of polystyrene of 13900. The actually measured acid value was 67 mgKOH / g.
Table 1 shows the specifications of each resin obtained in Production Examples 1 to 6.

1) PTG1000SN: Hodogaya Chemical Co., Ltd .: polytetramethylene glycol 2) DMBA: Nippon Kasei Co., Ltd .: dimethylolbutanoic acid 3) IPDI: isophorone diisocyanate 4) GMA: glycidyl methacrylate 5) SA: Succinic anhydride

[Production Example 7]
A four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet pipe, inlet pipe, thermometer, bisphenol A type epoxy having an epoxy equivalent of 650, a softening point of 81.1 ° C., and a melt viscosity (150 ° C.) of 12.5 poise 371 parts of resin, 925 parts of epichlorohydrin, and 463 parts of dimethyl sulfoxide were added and dissolved uniformly, and then 52.8 parts of 98.5% aqueous sodium hydroxide solution was added at 70 ° C. over 100 minutes with stirring. After the addition, the reaction was further carried out at 70 ° C. for 3 hours. Subsequently, most of the excess unreacted epichlorohydrin and dimethyl sulfoxide are distilled off under reduced pressure, the reaction product containing by-product salt and dimethyl sulfoxide is dissolved in 750 parts of methyl isobutyl ketone, and further 10 parts of 30% aqueous sodium hydroxide solution. And reacted at 70 ° C. for 1 hour. After completion of the reaction, washing was performed twice with 200 parts of water. After separation of oil and water, methyl isobutyl ketone is recovered by distillation from the oil layer, and an epoxy resin having an epoxy equivalent of 287, a hydrolyzable chlorine content of 0.07%, a softening point of 64.2 ° C., and a melt viscosity (150 ° C.) of 7.1 poise. 340 parts were obtained.

  287 parts of this epoxy resin was put into a four-necked flask equipped with another stirrer, reflux condenser, nitrogen inlet pipe, inlet pipe and thermometer, and further 72 parts of acrylic acid, 0.3 part of methylhydroquinone, cyclohexanone 194 The reaction mixture was dissolved by heating and stirring at 90 ° C. Subsequently, the reaction liquid was cooled to 60 ° C., 1.7 parts of triphenylphosphine was charged, and the reaction was performed at 100 ° C. for about 32 hours in the presence of oxygen to obtain a reaction product having an actually measured acid value of 1 mgKOH / g. Next, 78 parts of succinic anhydride and 42 parts of cyclohexanone are added to this and reacted at 95 ° C. for about 6 hours, and the photosensitive resin having a carboxyl group and an ethylenically unsaturated group whose main skeleton is a bisphenol A type epoxy resin. Got. Next, cyclohexanone was added to this solution to adjust the non-volatile content to 50.0%. The ethylenically unsaturated group equivalent of the nonvolatile content of the bisphenol A type epoxy resin prepared by this production example was 450 eq / g, the weight average molecular weight in terms of polystyrene was 7400, and the actually measured acid value was 100 mgKOH / g.

[Production Example 8]
To a four-necked flask equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, an inlet tube, and a thermometer, 330 parts of a cresol novolac epoxy resin having an epoxy equivalent of 218 g / eq (manufactured by Toto Kasei Co., Ltd .: YDCN-702). The mixture was melted by heating at 90 to 100 ° C. and stirred. Next, 120 parts of acrylic acid, 0.6 part of hydroquinone, and 5 parts of dimethylbenzylamine were added, and the mixture was heated to 115 ° C. with stirring in the presence of oxygen and reacted for 12 hours. Next, 400 parts of cyclohexanone was added to this flask and dissolved by heating to 70 ° C. Next, 81 parts of succinic anhydride was added, the temperature was raised to 95 ° C., and the mixture was stirred and reacted for 8 hours. After confirming that the absorption of the acid anhydride group has disappeared by FT-IR measurement, the photosensitive resin is cooled to room temperature and has a carboxyl group and an ethylenically unsaturated group whose main skeleton is a cresol novolak skeleton. Obtained. Next, cyclohexanone was added to this solution to adjust the nonvolatile content to 50.0%. The ethylenically unsaturated group equivalent of the polymer nonvolatile content of the acid anhydride-modified cresol novolak resin prepared by this production example is 319 g / eq, the weight average molecular weight in terms of polystyrene is 11000, and the acid value of the polymer nonvolatile content by measurement is It was 85 mgKOH / g.

[Production Example 9]
A dropping funnel was placed in a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, inlet tube, and thermometer, and 400 parts of cyclohexanone was charged into the flask, and the temperature was raised to 90 ° C. with stirring in a nitrogen atmosphere. did. In a separate container, 15 parts of methacrylic acid, 30 parts of methyl methacrylate, 30 parts of butyl methacrylate, 25 parts of benzyl methacrylate, 20 parts of azobisisobutyronitrile as a polymerization initiator and 100 parts of cyclohexanone are stirred and dissolved uniformly. did. The monomer solution was charged into a dropping funnel installed in the flask, and the monomer solution in the dropping funnel was dropped into the flask over 2 hours while stirring the flask at 90 ° C. in a nitrogen atmosphere. Stirring was continued at 90 ° C. even after completion of the dropping, and 0.5 part of azobisisobutyronitrile was charged into the flask after 2 hours from the end of the dropping. After 1 hour, 0.5 part of azobisisobutyronitrile was again added to the flask, and stirring was continued for another 2 hours. Thereafter, the flask was cooled to stop the reaction. A small amount of sampling was performed to obtain a carboxyl group-containing acrylic prepolymer having a polystyrene-equivalent weight average molecular weight of 18,700 and an acid value of 98 mgKOH / g of polymer non-volatile content.

  Next, nitrogen from the nitrogen inlet tube of this flask was stopped, switching to introduction of dry air, and 111 parts of glycidyl methacrylate, 6 parts of dimethylbenzylamine, and 0.3 part of hydroquinone as a polymerization inhibitor were added while stirring. , Reacted at 90 ° C. for 8 hours. After completion of the reaction, a small amount of sampling was performed to obtain a hydroxyl group-containing acrylic prepolymer having a polystyrene-equivalent weight average molecular weight of 19,900 and an actually measured acid value of 5 mg KOH / g of the nonvolatile polymer content.

Next, 63 parts of succinic anhydride was added to the flask and reacted for 6 hours with stirring at 90 ° C. in a dry air atmosphere. After confirming that the absorption of the acid anhydride group has disappeared by FT-IR measurement, it is cooled to room temperature to obtain a photosensitive resin having a carboxyl group and an ethylenically unsaturated group whose main skeleton is an acrylic resin. It was. Next, cyclohexanone was added to this solution to adjust the nonvolatile content to 50.0%. The ethylenically unsaturated group equivalent of the nonvolatile content of the acrylic resin prepared by this production example is 863 g / eq, the weight average molecular weight in terms of polystyrene is 22000, and the acid value of the polymer nonvolatile content measured is 70 mgKOH / g. It was.
Table 2 shows the specifications of each resin obtained in Production Examples 7 to 9.

[Example 1-1]
100 parts of the urethane resin (A-1) solution obtained in Production Example 1, 5.0 parts of Exolit OP-935 (manufactured by Clariant Japan Co., Ltd .: aluminum phosphinate) as the phosphinate (B), and then methyl ethyl ketone in this solution Is added so that the non-volatile content is 50.0%. The solution is stirred for 20 minutes, and then dispersed in an Eiger mill (manufactured by Eiger Japan) for 2 hours using zirconia beads having a diameter of 0.5 mm. Got.

[Example 1-2]
Dispersion 2 was obtained by the same composition and procedure as Example 1-1 except that Exolit OP-935 was changed to 10.0 parts.

[Example 1-3]
Dispersion 3 was obtained by the same formulation and procedure as Example 1-1 except that Exolit OP-935 was changed to 17.5 parts.

[Example 1-4]
Dispersion 4 was obtained by the same composition and procedure as in Example 1-1 except that Exolit OP-935 was changed to 22.5 parts.

[Example 1-5]
Instead of the urethane resin (A-1) solution, a dispersion 5 was obtained by the same formulation and procedure as in Example 1-3, except that the urethane resin (A-2) solution obtained in Production Example 2 was used. .

[Example 1-6]
Instead of the urethane resin (A-1) solution, a dispersion 6 was obtained by the same formulation and procedure as in Example 1-3, except that the urethane resin (A-3) solution obtained in Production Example 3 was used. .

[Example 1-7]
Instead of the urethane resin (A-1) solution, a dispersion 7 was obtained by the same formulation and procedure as in Example 1-3 except that the urethane resin (A-4) solution obtained in Production Example 4 was used. .

[Example 1-8]
Instead of the urethane resin (A-1) solution, a dispersion 8 was obtained in the same composition and procedure as in Example 1-3 except that the urethane resin (A-5) solution obtained in Production Example 5 was used. .

[Example 1-9]
Instead of the urethane resin (A-1) solution, a dispersion 9 was obtained in the same composition and procedure as in Example 1-3, except that the urethane resin (A-6) solution obtained in Production Example 6 was used. .

[Comparative Example 1-1]
A dispersion 9 was obtained by the same composition and procedure as in Example 1-1 except that Exolit OP-935 was changed to 1.0 part.

[Comparative Example 1-2]
Dispersion 10 was obtained by the same formulation and procedure as Example 1-1, except that Exolit OP-935 was changed to 30.0 parts.

[Comparative Example 1-3]
Instead of the urethane resin (A-1) solution, a dispersion 12 was obtained by the same formulation and procedure as in Example 1-3, except that the carboxylic acid-containing resin solution obtained in Production Example 7 was used.

[Comparative Example 1-4]
Instead of the urethane resin (A-1) solution, a dispersion 13 was obtained in the same composition and procedure as in Example 1-3, except that the carboxylic acid-containing resin solution obtained in Production Example 8 was used.

[Comparative Example 1-5]
Instead of the urethane resin (A-1) solution, a dispersion 14 was obtained by the same formulation and procedure as in Example 1-3, except that the carboxylic acid-containing resin solution obtained in Production Example 9 was used.

[Comparative Example 1-6]
Dispersion 15 was obtained by the same composition and procedure as Example 1-3 except that ammonium polyphosphate (manufactured by Clariant Japan Co., Ltd .: AP423) was used instead of Exolit OP-935.

  The following evaluations were performed on the obtained dispersions 1 to 15.

[Evaluation of volume average particle diameter of dispersed particles]
The volume average particle diameter (D ₅₀ ) of the dispersed particles of the obtained dispersion solution was measured with Mastersizer 2000 (MALVERN INSTRUMENTS Co., Ltd.) and evaluated according to the following criteria.
◎ ・ ・ ・ Volume average particle diameter is 0.1 μm or more and less than 0.5 μm ○ ・ ・ ・ Volume average particle diameter is 0.5 μm or more and 1 μm
Δ: Volume average particle diameter is greater than 1 μm and less than 2 μm × ・ ・ ・ Volume average particle diameter is 2 μm or more and less than 3 μm

[Evaluation of dispersion stability]
The obtained dispersion was allowed to stand at 40 ° C., the stability over time was confirmed, and evaluated according to the following criteria.
...: No change in the dispersion after standing for 4 weeks.....: Precipitates were formed in the dispersion or gelled for 2 to 4 weeks.
Δ: A precipitate was formed or gelled in the dispersion during 1 to 2 weeks.
X: A precipitate was formed or gelled in the dispersion within one week.

[Example 2-1]
Irgacure 907 (manufactured by Ciba Specialty Chemicals Co., Ltd .: 2-methyl-1- [4) as a photopolymerization initiator (D) with respect to 100 parts of the urethane resin (A-1) in the obtained dispersion solution 1 -(Methylthio) phenyl] -2-morpholino-1-propane) 6.0 parts, also DETX-S (manufactured by Nippon Kayaku Co., Ltd .: 2,4-diethylthioxanthone) 1.0 parts, containing ethylenically unsaturated group 10.0 parts Aronix M-310 (manufactured by Toagosei Co., Ltd .: trimethylolpropane PO-modified triacrylate) as the compound (E) and HP7200 (manufactured by Dainippon Ink & Chemicals, Inc .: dicyclopentadiene) as the thermosetting compound (F) Type epoxy) 25.0 parts, and methyl ethyl ketone was added to prepare a non-volatile content of 50.0%. And created a photosensitive flame retardant resin composition.

[Examples 2-2 to 2-6]
A photosensitive flame retardant resin composition was prepared by the same formulation and procedure as in Example 2-1, except that dispersions 2 to 6 were used instead of dispersion 1, respectively.

[Comparative Examples 2-1 to 2-9]
A resin composition was prepared by the same formulation and procedure as in Example 2-1, except that the dispersions 7 to 15 were used in place of the dispersion 1, respectively.

[Comparative Example 2-10]
Irgacure 907 (manufactured by Ciba Specialty Chemicals Co., Ltd .: 2-methyl-1- [4) as a photopolymerization initiator (D) with respect to 100 parts of the urethane resin (A-1) solution obtained in Production Example 1. -(Methylthio) phenyl] -2-morpholino-1-propane) 6.0 parts, also DETX-S (manufactured by Nippon Kayaku Co., Ltd .: 2,4-diethylthioxanthone) 1.0 parts, containing ethylenically unsaturated group 10.0 parts Aronix M-310 (manufactured by Toagosei Co., Ltd .: trimethylolpropane PO-modified triacrylate) as the compound (E) and HP7200 (manufactured by Dainippon Ink & Chemicals, Inc .: dicyclopentadiene) as the thermosetting compound (F) Type epoxy) 25.0, SPB-100 (Otsuka Chemical Co., Ltd .: Phenoxyphosphazene) 80.0 parts as a flame retardant It was prepared a resin composition.
The following evaluation was performed about the obtained photosensitive flame-retardant resin composition and resin composition.

[Create sample A]
The photosensitive flame-retardant resin composition and the resin composition obtained in Examples 2-1 to 6 and Comparative Examples 2-1 to 10 were used on Kapton 100H (manufactured by Toray DuPont Co., Ltd .: polyimide film (25 μm thickness)). The film was applied to a dry film thickness of 25 μm, dried with a hot air dryer at 80 ° C. for 30 minutes, and then cooled to room temperature. Next, using an ultraviolet exposure device (USHIO INC .: “UVC-2534 / 1MNLC3-AA08”, 120 W / cm metal halide lamp, 1 lamp), ultraviolet light with an integrated light quantity of 300 mJ / cm ² was irradiated and hot air at 150 ° C. It was heat-cured (post-cured) for 1 hour with a dryer. The obtained cured product was cooled to room temperature. This is designated as sample A.

[Create sample B]
The photosensitive flame-retardant resin composition and resin composition obtained in Examples 2-1 to 6 and Comparative Examples 2-1 to 10 were combined with a copper-clad laminated polyimide film (manufactured by Nippon Steel Chemical Co., Ltd .: Espanex MC18-25). -00FRM) was coated on the copper surface side so as to have a dry film thickness of 25 μm, dried in a hot air drier at 80 ° C. for 30 minutes, and then cooled to room temperature. Next, using an ultraviolet exposure device (USHIO INC .: “UVC-2534 / 1MNLC3-AA08”, 120 W / cm metal halide lamp, 1 lamp), ultraviolet light with an integrated light quantity of 300 mJ / cm ² was irradiated, and hot air at 150 ° C. It was heat-cured (post-cured) for 1 hour with a dryer. The obtained cured product was cooled to room temperature. This is designated as sample B.

[Create sample C]
Comb-shaped copper circuits of the line width / space width (100 μm / 100 μm) of the photosensitive flame retardant resin compositions and resin compositions obtained in Examples 2-1 to 6 and Comparative Examples 2-1 to 10 After applying to a 25 μm-thick polyimide substrate (manufactured by Yamashita Materials Co., Ltd.) on which (copper thickness 17 μm) is formed so that the dry film thickness is 25 μm, and drying it with a hot air dryer at 80 ° C. for 30 minutes And cooled to room temperature. Next, using an ultraviolet exposure device (USHIO INC .: “UVC-2534 / 1MNLC3-AA08”, 120 W / cm metal halide lamp, 1 lamp), ultraviolet light with an integrated light quantity of 300 mJ / cm ² was irradiated and hot air at 150 ° C. It was heat-cured (post-cured) for 1 hour with a dryer. The resulting cured film was cooled to room temperature. This is sample C.

[Evaluation of polyimide adhesion]
According to JIS K5400, 100 grids of 1 mm × 1 mm were made for sample A, and a peeling test was performed using a cellophane tape. The peeled state of the grid was observed and evaluated according to the following criteria.
○: No peeling.
Δ: 20% or less of the grids peel off.
X: 21% or more of the grids peeled off.

[Evaluation of copper adhesion]
A sample test piece is prepared by sticking the cured surface of Sample B cut to a width of 1 cm and a length of 20 cm and a SUS plate using a double-sided adhesive tape, and a 180 ° peel test (pulling speed: 100 mm / min) is performed. Then, the adhesive force between the copper surface and the cured product was measured and evaluated according to the following criteria.
◎ ・ ・ ・ Peeling force is 2.0 N / cm or more ○ ・ ・ ・ Peeling force is 1.5 to 1.9 N / cm
Δ: peeling force is 1.0 to 1.4 N / cm
X: Peeling force is less than 1.0 N / cm

[Evaluation of bendability]
The sample C test piece was bent at 180 degrees, a load of 200 g / cm was applied to the bent portion for 5 seconds, the same portion was then bent 180 degrees to the opposite side, and a load of 200 g / cm was applied to the bent portion for 5 seconds. The above operation was defined as one cycle, and the number of cycles until cracks occurred in the cured film was measured and evaluated according to the following criteria.
◎ ... 20 cycles or more ○ ... 10-19 cycles Δ ... 5-10 cycles x ... less than 5 cycles

[Evaluation of solder heat resistance]
A rosin-based flux (manufactured by Asahi Chemical Laboratory: SPEEDY FLUX P-550-5) is applied to Sample A and immersed in a 260 ° C. solder bath (JIS C 6481) for 5 seconds. Judged as follows.
○… There is no abnormality in the appearance of the cured product, and there is no swelling or peeling.
X: The entire cured product has swelling or peeling.

[Evaluation of flame retardancy]
Sample A was tested in accordance with UL94 flame retardancy test and evaluated according to the following criteria.
VTM-0 is equivalent to UL VTM-0. The flame extinguishing time after ignition of the test piece is within 3 seconds.
VTM-0 ○ ... UL VTM-0 equivalent. The flame extinguishing time after ignition of the test piece is within 3 to 6 seconds.
HB ◎ ... UL HB equivalent. Extinguish from the ignition point of the specimen to 25mm.
HB ○ ... UL HB equivalent. Flame extinguishing from the ignition point of the test piece to 25-100 mm.
X: Not extinguished by 100 mm in UL HB test or complete combustion.
The high flame retardancy is in the order of VTM-0-> VTM-0 ○> HB ◎> HB ○> ×.

[Evaluation of solvent resistance]
Sample A is immersed in methyl ethyl ketone and isopropyl alcohol for 5 minutes at room temperature. After confirming that there was no more in appearance, a peeling test using a cellophane tape was performed, and evaluation was performed according to the following criteria.
○… There is no abnormality in the appearance of the cured product, and there is no swelling or peeling.
Δ: There is a slight swelling or peeling around the end of the cured product (between the coated portion and the polyimide base material).
X: The cured product has swelling and peeling.

[Evaluation of acid resistance]
Sample A is immersed in a 10% aqueous hydrochloric acid solution at room temperature for 5 minutes. After confirming that there was no more in appearance, a peeling test using a cellophane tape was performed, and evaluation was performed according to the following criteria.
○… There is no abnormality in the appearance of the cured product, and there is no swelling or peeling.
Δ: There is a slight swelling or peeling around the end of the cured product (between the coated portion and the polyimide base material).
X: The cured product has swelling and peeling.

[Evaluation of developability]
On the PET film, the photosensitive flame retardant resin composition and the resin composition obtained in Examples 2-1 to 6 and Comparative examples 2-1 to 10 were applied so that the dry film thickness was 25 μm. It dried for 20 minutes with the hot-air dryer of ° C. The dried coating film was adhered to the copper surface side of a copper-clad laminated polyimide film (Espanex MC18-25-00FRM, manufactured by Nippon Steel Chemical Co., Ltd.) with a vacuum laminate (60 ° C., 0.2 Mpa = 2 kg / cm ² ). . Subsequently, a negative film having a resist pattern [φ100 μm hole] is brought into close contact with the PET film, and irradiated with ultraviolet rays (400 mJ / cm ² ) using an ultraviolet exposure device (EXM-1201-F02 manufactured by Oak Seisakusho, mercury short arc lamp). )did. Next, the PET film was peeled off, and a 1% sodium carbonate aqueous solution was sprayed at a spray pressure of ² kg / cm ² for 60 seconds to develop. Then, heat cure with a hot air dryer at 150 ° C. for 1 hour, observe the hole part of φ100 μm with a magnifying glass, and the resist layer is developed and the copper surface is exposed (the part where the hole is opened) The diameter was measured, and the resolution was judged according to the following criteria.
◎ ・ ・ ・ Opening diameter is 90μm ～ 100μm
○ ・ ・ ・ Opening diameter is 80μm ～ 89μm
Δ: Opening diameter is 70 μm to 79 μm
× ・ ・ ・ Opening diameter is less than 70μm

[Evaluation of electrical insulation]
The insulation resistance value was measured using sample C (initial value: 5 × 10 ¹³ Ω each), and then an energization test was performed under conditions of 130 ° C., relative humidity 85%, 20 V, and the resistance value was an initial value (each 5 The time from when it was reduced to 10 × 10 ¹³ Ω until the value of 5 × 10 ⁷ Ω or less was steadily measured was measured and evaluated according to the following criteria. The longer the time until the resistance value decreases, the better the electrical insulation.
◎ ... 100 hours or more.
○: 50 hours or more and less than 100 hours.
Δ: 25 hours or more and less than 50 hours.
X: Less than 25 hours.

<Evaluation results>
The evaluation results of Examples 2-1 to 9 and Comparative Examples 2-1 to 7 are shown in Table 4.

  From the results of Table 4, the examples used urethane resin (A) and phosphinate (B), such as polyimide adhesion, solder heat resistance, developability, solvent resistance, acid resistance, electrical insulation, etc. It can be seen that the material has excellent physical properties, can be compatible with flexibility and bendability, and has improved copper adhesion. Therefore, it can be seen that it can be suitably used for a printed wiring board or the like.

Claims (5)

A urethane resin (A) having a carboxyl group and an ethylenically unsaturated group;
A photosensitive flame retardant comprising 5 to 50 parts by weight of a phosphinic acid salt (B) having a volume average particle diameter of 0.1 to 1 μm with respect to 100 parts by weight of a urethane resin (A). Resin composition. Urethane resin (A)
A carboxyl group in the carboxyl group-containing urethane prepolymer (a);
A hydroxyl group in the hydroxyl group-containing urethane prepolymer (c) obtained by reacting an epoxy group or oxetane group in the compound (b) having an epoxy group or oxetane group and an ethylenically unsaturated group;
The photosensitive flame retardant resin composition according to claim 1, wherein the acid anhydride group in the polybasic acid anhydride (d) is reacted. The photosensitive flame retardant resin composition according to claim 1 or 2, wherein the phosphinic acid salt (B) is represented by the following general formula (1).
General formula (1)

(R1 and R2 are the same or different and represent a linear or branched alkyl group having 1 to 6 carbon atoms or an aryl group, and M represents Mg, Ca, Al, Sb, Sn, Ge, Ti. , Zn, Fe, Zr, Ce, Bi, Sr, Mn, Li, Na, and at least one metal selected from the group consisting of K, and n is an integer of 1 to 4.   Hardened | cured material formed by hardening | curing the photosensitive flame-retardant resin composition in any one of Claims 1-3. The printed wiring board formed by laminating | stacking the cured film of the photosensitive flame-retardant resin composition in any one of Claims 1-3.