JP4572753B2 - Resist ink composition - Google Patents

Description

  The present invention has a wide thermal management range during preliminary drying, good alkali developability, high sensitivity to active energy rays, excellent heat resistance after soldering, adhesion, chemical resistance, solvent resistance The present invention relates to a resist ink composition useful as an alkali developing resist ink having a good balance of various characteristics such as.

  In recent years, resist pattern formation methods for printed wiring boards have used organic solvents as developing solutions and those developed with dilute alkaline aqueous solutions for the purpose of increasing the density. In addition to the above problems, the latter alkali development type resist ink is attracting attention because it has a problem that the solvent is expensive and further has poor chemical resistance and solvent resistance.

  As the main agent for the alkali development type resist ink, for example, those using acid pendant type epoxy acrylate obtained by reacting an unsaturated monocarboxylic acid with an epoxy resin and adding a polybasic acid anhydride are widely used. However, in recent years, there has been a growing need for new exposure systems such as direct exposure using laser light and high-sensitivity resist inks that can cope with higher speed production lines.

  In response to such needs, as a highly sensitive resist ink composition, for example, a resin obtained by reacting a reaction product of an epoxy resin and an unsaturated monocarboxylic acid with a dibasic acid anhydride, and an epoxy group A technique using a photosensitive resin obtained by reacting a contained radical polymerizable monomer as a main agent is disclosed (for example, see Patent Document 1). However, the resist ink using the main agent has a problem that the heat management width during preliminary drying is extremely narrow and the development speed is slow. The thermal management width is the management of the thermal limit that can maintain the developability of the unexposed part after the coating film is dried. If the thermal management width is narrow, an alkali development type resist ink is applied to the printed wiring board. In the drying process for removing the solvent, the resin composition of the coating film starts to harden for a time or temperature exceeding the allowable range, and then exposed and developed, so that the unexposed portion is difficult to be removed by the developer. The problem arises. For this reason, the drying time and drying temperature are limited, the number of coatings must be restricted, tackiness remains due to the remaining solvent, and problems such as deterioration of finger-drying properties occur.

JP-A-10-282665 (page 3-5)

  In view of the above situation, the problem of the present invention is that the thermal management width during pre-drying is wide, the alkali developability is good, the active energy ray is highly sensitive, the solder heat resistance after thermosetting, the adhesion, An object of the present invention is to provide a resist ink composition useful as an alkali developing resist ink having a good balance of various properties such as chemical resistance and solvent resistance.

  As a result of intensive studies to achieve the above object, the present inventors have added a polybasic acid anhydride to a secondary hydroxyl group in a reaction product of a polyfunctional epoxy resin and a compound having the following specific structure. Photosensitive resin obtained by reacting a carboxyl group in an adduct obtained by addition reaction with an epoxy group in an epoxy group-containing radical polymerizable unsaturated monomer, a heat-reactive curing agent, and a diluent And a composition containing a polymerizable initiator have a wide thermal management range during preliminary drying, good alkali developability, high sensitivity to active energy rays, excellent heat resistance after soldering, and adhesion The present inventors have found that the present invention is a resist ink composition having a good balance of various properties such as chemical resistance and solvent resistance and useful as an alkali development type solder resist ink.

  That is, the present invention relates to a polyfunctional epoxy resin (a1) and the following general formula (1):

（式中、ｎは１〜１０の整数であり、Ｒ_１は水素原子又はメチル基であり、Ｒ_２は炭素数２〜１０の炭化水素基であって、該炭化水素基中の水素原子の一部又は全部がフッ素原子、臭素原子又は塩素原子で置換されていてもよい。）
で示される化合物（ａ２）との反応物中の二級水酸基に多塩基酸無水物（ａ３）を付加反応させて得られる付加体中のカルボキシル基と、エポキシ基含有ラジカル重合性不飽和単量体（ａ４）中のエポキシ基とを反応させることによって得られる感光性樹脂（Ａ１）、熱反応性硬化剤（Ｂ）、希釈剤（Ｃ）及び光重合開始剤（Ｄ）を含有することを特徴とするレジストインキ組成物を提供するものである。

(In the formula, n is an integer of 1 to 10, R ₁ is a hydrogen atom or a methyl group, R ₂ is a hydrocarbon group having 2 to 10 carbon atoms, and the hydrogen atom in the hydrocarbon group is Part or all may be substituted with a fluorine atom, a bromine atom or a chlorine atom.)
And a carboxyl group in an adduct obtained by addition reaction of a polybasic acid anhydride (a3) with a secondary hydroxyl group in a reaction product with the compound (a2) represented by formula (1) and an epoxy group-containing radical polymerizable unsaturated monomer. Containing a photosensitive resin (A1) obtained by reacting with an epoxy group in the body (a4), a heat-reactive curing agent (B), a diluent (C) and a photopolymerization initiator (D). A featured resist ink composition is provided.

  Furthermore, the present invention relates to a polyfunctional epoxy resin (a1) and the following general formula (1):

（式中、ｎは１〜１０の整数であり、Ｒ_１は水素原子又はメチル基であり、Ｒ_２は炭素数２〜１０の炭化水素基であって、該炭化水素基中の水素原子の一部又は全部がフッ素原子、臭素原子又は塩素原子で置換されていてもよい。）
で示される化合物（ａ２）及び（メタ）アクリル酸（ａ５）との反応物中の二級水酸基に多塩基酸無水物（ａ３）を付加反応させて得られる付加体中のカルボキシル基と、エポキシ基含有ラジカル重合性不飽和単量体（ａ４）中のエポキシ基とを反応させることによって得られる感光性樹脂（Ａ２）、熱反応性硬化剤（Ｂ）、希釈剤（Ｃ）及び光重合開始剤（Ｄ）を含有することを特徴とするレジストインキ組成物をも提供するものである。

(In the formula, n is an integer of 1 to 10, R ₁ is a hydrogen atom or a methyl group, R ₂ is a hydrocarbon group having 2 to 10 carbon atoms, and the hydrogen atom in the hydrocarbon group is Part or all may be substituted with a fluorine atom, a bromine atom or a chlorine atom.)
A carboxyl group in an adduct obtained by addition reaction of a polybasic acid anhydride (a3) to a secondary hydroxyl group in a reaction product with the compound (a2) and (meth) acrylic acid (a5) represented by the formula: Photosensitive resin (A2) obtained by reacting with an epoxy group in the group-containing radically polymerizable unsaturated monomer (a4), a heat-reactive curing agent (B), a diluent (C), and photopolymerization initiation The present invention also provides a resist ink composition containing an agent (D).

  According to the present invention, the thermal management width at the time of preliminary drying is wide, the touch-drying property is excellent, the alkali developability is good, the active energy ray is highly sensitive, and after heat curing, the solder heat resistance is excellent, and the adhesion It is possible to provide a resist ink composition useful as an alkali development type solder resist ink having a good balance of various properties such as property, chemical resistance and solvent resistance.

  The photosensitive resin (A1) used in the present invention is obtained by esterifying the polyfunctional epoxy resin (a1) and the compound (a2) represented by the general formula (1), and then in the reaction product. It is obtained by reacting an addition reaction product obtained by adding a polybasic acid anhydride (a3) to a secondary hydroxyl group and an epoxy group-containing radical polymerizable unsaturated monomer (a4). The photosensitive resin (A2) used in the present invention comprises a polyfunctional epoxy resin (a1), a mixture of the compound (a2) represented by the general formula (1) and (meth) acrylic acid (a5). After the esterification reaction, an addition reaction product obtained by adding the polybasic acid anhydride (a3) to the secondary hydroxyl group in the reaction product, an epoxy group-containing radical polymerizable unsaturated monomer (a4), It is obtained by reacting.

  Among these, it is preferable that the acid value of the photosensitive resin (A1) or the photosensitive resin (A2) is 30 to 150 mgKOH / g from the point that a resist ink having good developability with a dilute alkali solution can be obtained. In particular, it is preferably 40 to 120 mgKOH / g.

  The polyfunctional epoxy resin (a1) used here is not particularly limited, and examples thereof include novolak resins such as phenol novolak resin, cresol novolak resin, halogenated phenol novolak resin, alkylphenol novolak resin, epichlorohydrin, and methyl. Novolak-type epoxy resin obtained by reacting with epichlorohydrin, etc .; diglycidyl ether of bisphenol obtained by reacting bisphenols such as bisphenol A, bisphenol F, bisphenol S, tetrabromobisphenol A with epichlorohydrin, methyl epichlorohydrin, etc. Bisphenol A, bisphenol F, bisphenol S, tetrabromobisphenol Bisphenol type epoxy resin with high molecular weight such as trisphenol methane, tris-resole methane, etc., trisphenol methane type epoxy resin obtained by reacting epichlorohydrin, methyl epichlorohydrin, etc .; triglycidyl isocyanurate, biphenyl diglycidyl ether, etc. And an alicyclic epoxy resin; a copolymer type epoxy resin such as a copolymer of glycidyl methacrylate and styrene and methylstyrene, a copolymer of glycidyl methacrylate and cyclohexylmaleimide, and the like. The polyfunctional epoxy resin (a1) may be used alone or in combination of two or more.

  Among these, novolac type epoxy resins are preferable because they have good heat resistance and chemical resistance after thermosetting. Further, the softening point of the polyfunctional epoxy resin (a1) is preferably in the range of 50 to 105 ° C., and in particular, the drying property at the time of preliminary drying of the resist ink and the solder heat resistance after thermosetting are improved. A range of 100 ° C. is more preferable.

  The compound (a2) has two or more ester bonds in the molecule as indicated by the general formula (1). By introducing the structure into the molecule, the hydrophilicity of the resin can be increased, and the thermal management width and developability are significantly improved. In addition, the compound (a2) has a long molecular chain as an unsaturated monobasic acid to be reacted with the polyfunctional epoxy resin (a1) as compared with conventionally used (meth) acrylic acid. The photosensitive resin obtained using (a2) is bulky in terms of molecular structure, and the sensitivity of the resist ink to the active energy rays can be increased.

  Examples of the compound (a2) include polylactone (meth) acrylates obtained by chain reaction of ε-caprolactone with (meth) acrylic acid, and (meth) acrylic acid dimers.

  The photosensitive resin (A2) used in the resist ink composition according to the second invention of the present invention is the compound (a2) as an unsaturated monobasic acid to be reacted with the polyfunctional epoxy resin (a1). And (meth) acrylic acid (a5) are used in combination. This is used in combination for the purpose of maintaining the sensitivity of the resist ink to be obtained and the hardness of the coating film after heat curing. The photosensitive resin (A1) is appropriately selected depending on the desired sensitivity, coating film hardness, and the like. Alternatively, it is preferable to use a photosensitive resin (A2).

  When (meth) acrylic acid (a5) is used in combination, the equivalent ratio of the compound (a2) to (meth) acrylic acid (a5) is sufficient to improve the thermal management width and developability. And (a2) :( a5) = 1: 99 to 80:20, particularly preferably (a2) from the viewpoint that physical properties such as drying property and heat resistance during precuring are good. : (A5) = 5: 95 to 50:50 is preferable.

  The polybasic acid anhydride (a3) is not particularly limited. For example, maleic anhydride, succinic anhydride, itaconic anhydride, dodecyl succinic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, 3- Methyltetrahydrophthalic anhydride, 4-methyltetrahydrophthalic anhydride, 3-methylhexahydrophthalic anhydride, 4-methylhexahydrophthalic anhydride, 3,4-dimethyltetrahydrophthalic anhydride, 4- (4-methyl-3 -Pentenyl) tetrahydrophthalic anhydride, 3-butenyl-5,6-dimethyltetrahydrophthalic anhydride, 3,6-endomethylene-tetrahydrophthalic anhydride, 7-methyl-3,6-endomethylenetetrahydrophthalic anhydride, benzophenone Aliphatic acid anhydrides such as tetracarboxylic acid anhydride; anhydrous lid Acid, tetrachlorophthalic anhydride, tetrabromophthalic anhydride, chlorendic anhydride, trimellitic anhydride, pyromellitic anhydride, aromatic monoacid anhydride such as benzophenone tetracarboxylic acid anhydride. Of these, aliphatic acid anhydrides such as succinic anhydride, tetrahydrophthalic anhydride, and hexahydrophthalic anhydride are preferred because the solvent solubility of the unreacted portion of the resist ink obtained is good, and two or more of these are used in combination. You may do it. Among these, since the heat management width of the resulting resist ink and the heat resistance of the coating film after thermosetting are improved, tetrahydrophthalic anhydride, succinic anhydride, or a combination of these two acid anhydrides is used. preferable.

  The epoxy group-containing radically polymerizable unsaturated monomer (a4) is not particularly limited, but glycidyl (meth) acrylate is preferred from the viewpoint that the effects of the present invention are remarkable.

  The polyfunctional epoxy resin (a1) and the compound (a2), or the mixture of the compound (a2) and (meth) acrylic acid (a5) and the secondary hydroxyl group in the reaction product obtained by the esterification reaction are polybasic acid. An acid pendant epoxy (meth) acrylate is obtained by reacting the anhydride (a3). In this step, the polyfunctional epoxy resin (a1) and the compound (a2), or a mixture of the compound (a2) and (meth) acrylic acid (a5) and the polybasic acid anhydride (a3) are reacted together. Although a technique is also possible, an unreacted polybasic acid anhydride (a3) reacts with the secondary hydroxyl group generated by this reaction to generate a carboxyl group, and this carboxyl group and the polyfunctional epoxy resin (a1) Further, the molecular weight is increased by a side reaction that causes cross-linking between molecules to cause thickening and gelation. Therefore, the polyfunctional epoxy resin (a1) and the compound (a2), or the compound (a2) and A method of reacting with a mixture of (meth) acrylic acid (a5) to obtain an epoxy (meth) acrylate, and reacting this with a polybasic acid anhydride (a3) is preferred. The acid pendant epoxy (meth) acrylate obtained here can be reacted with an epoxy group-containing radically polymerizable unsaturated monomer (a4) to obtain a photosensitive resin (A1) or a photosensitive resin (A2). . These reactions are described in detail below.

  First, in the case where the multifunctional epoxy resin (a1), the compound (a2) and the (meth) acrylic acid (a5) are used in combination as the step 1, a mixture of the compound (a2) and the (meth) acrylic acid (a5) Are subjected to an esterification reaction using an esterification catalyst as necessary to obtain an epoxy (meth) acrylate. The reaction ratio when the polyfunctional epoxy resin (a1) and the compound (a2), or the mixture of the compound (a2) and (meth) acrylic acid are reacted is not particularly limited. It is preferable to react 0.8 to 1.1 mol of the compound (a2) or a mixture of the compound (a2) and (meth) acrylic acid (a5) with respect to 1 mol of the epoxy group of the epoxy resin (a1). That is, the following polybasic acid anhydride (a3) and compound (a2) or a mixture of compound (a2) and (meth) acrylic acid (a5) are reacted in a range of 0.8 mol or more. The gelation during the reaction can be satisfactorily suppressed, and by reacting in the range of 1.1 mol or less, the resulting resist ink can be dried after preliminary drying, heat resistance of the coating film after heat curing, Excellent chemical and plating resistance. From the viewpoint of excellent balance between these performances and excellent sensitivity and storage stability of the resist ink, the compound (a2) or the compound (a2) and the (meta) are added to 1 mol of the epoxy group of the polyfunctional epoxy resin (a1). ) It is preferable to use a mixture with acrylic acid (a5) in a range of 0.90 to 1.05 mol.

  The esterification catalyst is not particularly limited, but tertiary amines such as triethylamine, N, N-dimethylbenzylamine, N, N-dimethylaniline, diazabicyclooctane; trimethylbenzylammonium chloride, methyl Quaternary ammonium salts such as triethylammonium chloride; phosphines of triphenylphosphine and tributylphosphine; imidazoles such as 2-methylimidazole, 1,2-dimethylimidazole and 2-ethyl-4-methylimidazole; and triphenylstibine Can be mentioned.

  In addition, the reaction between the polyfunctional epoxy resin (a1) and the compound (a2) or the mixture of the compound (a2) and (meth) acrylic acid (a5) is performed in the presence of a diluent to suppress gelation. From the point of view, it is preferable. Diluents that can be used include, for example, ketones such as ethyl methyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene; glycol ethers such as dipropylene glycol dimethyl ether and dipropylene glycol diethyl ether ; Esters such as ethyl acetate, butyl acetate, butyl cellosolve acetate, propylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate; aliphatic hydrocarbons such as octane and decane, petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, solvent naphtha, etc. And organic solvents such as petroleum solvents. Among these, propylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate can be used alone, or propylene glycol monomethyl ether can be reacted under particularly high temperature conditions, and the smoothness after preliminary drying of the resist ink is good. The combined use of ether acetate and ketones or the combined use of diethylene glycol monoethyl ether acetate and petroleum solvents is preferred.

  In addition, it is desirable to use a polymerization inhibitor from the viewpoint of suppressing gelation during the reaction. For example, hydroquinone, methylhydroquinone, methoquinone, toluhydroquinone, tolquinone, 1,4-naphthoquinone, phenothiazine, ditertiarybutylhydroxytoluene, An aluminum salt of N-nitrosophenylhydroxyamine is preferred.

  As the reaction temperature in the esterification step, the reaction can suitably proceed at 60 to 150 ° C. regardless of the timing of addition of the esterification catalyst. It is preferable to suppress the initial side reaction as much as possible. For that purpose, the reaction temperature is preferably 60 to 120 ° C. in a relatively low temperature range. In particular, the reaction temperature immediately after the addition of the esterification catalyst is preferably 60 to 110 ° C. Further, the total reaction time in the above steps is preferably 5 to 40 hours, although it varies depending on the scale.

  In the above step, the esterification catalyst is added when the polyfunctional epoxy resin (a1) and the compound (a2) or the mixture of the compound (a2) and (meth) acrylic acid (a5) is reacted (collective addition). However, a method (multistage addition) in which a part of the esterification catalyst is added (primary addition) to advance the reaction and then the esterification catalyst is added (secondary addition) suppresses side reactions. And the reaction time is shortened. The amount of the catalyst used in the primary addition and the secondary addition is not particularly limited, but it is preferable to add 50 to 90% by weight of the total catalyst amount in the primary addition and the remainder in the secondary addition.

  Next, as step 2, the epoxy (meth) acrylate obtained in the above step is reacted with the polybasic acid anhydride (a3) to obtain an acid pendant type epoxy acrylate. At this time, the reaction ratio of the epoxy (meth) acrylate and the polybasic acid anhydride (a3) is not particularly limited, but a practical resist ink having developability with a dilute alkali solution can be obtained. Since the reactivity with the heat-reactive curing agent (B) at the time of preliminary drying can be suppressed, the acid anhydride group of the polybasic acid anhydride (a3) is added to 0.3 mol per 1 mol of the hydroxyl group of the epoxy (meth) acrylate. It is preferable to make it react in the ratio which will be -1.0 mol, and it is especially preferable to make it react in the range of 0.40-0.95 mol with respect to 1 mol of hydroxyl groups of an epoxy (meth) acrylate.

  In addition, the reaction temperature in step 2 is not particularly limited, but is preferably 60 to 150 ° C. The reaction time in step 2 is preferably 1 to 10 hours.

  The photosensitive resin (A1) or photosensitive resin (A2) used in the present invention is an epoxy in the epoxy group-containing radical polymerizable unsaturated monomer (a4), in the carboxyl group in the acid pendant type epoxy (meth) acrylate. It is obtained by reacting a group. As the reaction ratio of the acid pendant type epoxy acrylate and the epoxy group-containing radical polymerizable unsaturated monomer (a4), the carboxyl group in the acid pendant type epoxy acrylate and the epoxy group-containing radical polymerizable unsaturated monomer (a4) ) In an equivalent ratio with epoxy group in (carboxyl group in acid pendant type epoxy acrylate) / {epoxy group in epoxy group-containing radical polymerizable unsaturated monomer (a4)} = 1 / 0.05- 1 / 0.6 is a ratio that dramatically improves the sensitivity of the resulting resist ink, and the sensitivity is excellent in dilute alkali developability when the corresponding amount ratio is 0.6 mol or less. In addition to obtaining a resin, a resist ink having good drying properties after preliminary drying is preferable. Moreover, by adjusting to the said range, the balance of the molecular weight and acid value of the photosensitive resin finally obtained can be adjusted to an appropriate range. (Carboxyl group in acid pendant type epoxy acrylate) / {epoxy group in epoxy group-containing radical polymerizable unsaturated monomer (a4)} is in a range of 1 / 0.1 to 1 / 0.5. More preferred.

  Although it does not restrict | limit especially as reaction temperature at the time of making an epoxy group containing radically polymerizable unsaturated monomer (a4) react with the carboxyl group in the said acid pendant type epoxy (meth) acrylate, It is 60-150 degreeC. Is preferred. The reaction time is not particularly limited, but is preferably 1 to 10 hours.

  Examples of the heat-reactive curing agent (B) used in the present invention include amino resins such as epoxy resins; butoxylated melamine resins, methoxylated melamine resins, and benzoguanamine-based cocondensation resins. Among these, an epoxy resin is preferable because the heat resistance and solvent resistance of the cured product are particularly good. As this epoxy resin, for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, alicyclic epoxy resin, trisphenol methane type epoxy resin, rubber modified epoxy resin, Examples include tris (2,3-epoxypropyl) isocyanurate, diphenyldiglycidyl ether, tetramethyldiphenyldiglycidyl ether, and an epoxy resin containing an oxazolidone ring. Among these, a cresol novolac type epoxy resin and an epoxy resin containing an oxazolidone ring are preferable from the viewpoint of the heat management width of the resist ink to be obtained and the heat resistance of the coating film.

  Although there is no restriction | limiting in particular as an epoxy resin containing the said oxazolidone ring, For example, the epoxy resin etc. which are obtained by making a polyfunctional epoxy resin and aromatic monoisocyanates react are mentioned.

  Moreover, when using the said epoxy resin as a heat-reactive hardener (B), it is preferable to use a hardening accelerator together. Specific examples of the curing accelerator include epoxy curing accelerators such as melamine derivatives, imidazole derivatives, dicyandiamide, and phenol derivatives.

  The amount of the heat-reactive curing agent (B) used is preferably 5 to 40 parts by weight with respect to 100 parts by weight of the photosensitive resin (A1) or the photosensitive resin (A2). That is, by using 5 parts by weight or more, the cured film obtained finally has excellent physical properties such as heat resistance, solvent resistance, acid resistance, adhesion, and electrical characteristics such as insulation resistance. Sufficient performance can be obtained. On the other hand, when the amount is 40 parts by weight or less, the photosensitivity and developability are excellent.

  The diluent (C) used in the present invention is not particularly limited. For example, ketones such as ethyl methyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene; methyl cellosolve , Glycol ethers such as butyl cellosolve, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol diethyl ether; ethyl acetate, butyl acetate, butyl cellosolve acetate, propylene glycol monomethyl ether acetate, diethylene glycol Esters such as monoethyl ether acetate; Alcohols such as ethanol, propanol, ethylene glycol, and propylene glycol; Octa , Decane and other aliphatic hydrocarbons; petroleum solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha; 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate , N-vinylpyrrolidone, N-vinylcaprolactam, acryloylmorpholine, methoxytetraethylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, polyethylene glycol di (meth) acrylate, N, N-dimethylacrylamide, melamine (meth) Acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate Glycerol, diglycidyl ether di (meth) acrylate, isobornyl (meth) acrylate, or polyhydric alcohols such as hexanediol, trimethylolpropane, pentaerythritol ditrimethylolpropane, dipentaerythritol, tris-hydroxyethyl isocyanurate, or Examples thereof include photopolymerizable reactive diluents such as polyvalent (meth) acrylates of these ethylene oxide or propylene oxide adducts. Among these, propylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate alone, or a combination of propylene glycol monomethyl ether acetate and ketones, or a combination of diethylene glycol monoethyl ether acetate and a petroleum solvent is preferable, and photopolymerization is further possible. It is preferable to use a reactive diluent in combination.

  The diluent (C) is used alone or as a mixture of two or more, and the content thereof is preferably 30 to 300 parts by weight per 100 parts by weight of the photosensitive resin (A1) or the photosensitive resin (A2). Particularly preferred is 50 to 200% by weight.

  Examples of the photopolymerization initiator (D) used in the present invention include acetophenone, 2,2-diethoxy-2-phenylacetophenone, p-dimethylaminopropiophenone, cycloacetophenone, 2-methyl-1- [4- Acetophenones such as (methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1; benzophenone, 2-chlorobenzophenone, p, benzophenones such as p-bisdiethylaminobenzophenone, P, P-bisdiethylaminobenzophenone, 4-benzoyl-4′-methyldiphenyl sulfide; benzoin ethers such as benzyl, benzoin, benzoin methyl ether, benzoin isobutyl ether; Ketals such as tilketal; thioxanthones such as thioxanthone, 2-chlorothioxanthone, 2,4-diethylthioxanthone, 2-isopropylthioxanthone; anthraquinone, 2,4,5-triarylimidazole dimer, 2,4,6- Examples include tris-S-triazine, 2,4,6-trimethylbenzoyldiphenylphosphine oxide. Among these, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one and 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1 Is preferred because of its high reactivity. These photopolymerization initiators (D) can be used alone or in combination of two or more.

  The amount of the photopolymerization initiator (D) is not particularly limited, but is usually 0.5 to 50 parts by weight with respect to 100 parts by weight of the photosensitive resin (A1) or the photosensitive resin (A2). It is preferable that it is the range of these. That is, when it is 0.5 parts by weight or more, the photocuring reaction of the photosensitive resin proceeds well, and when it is 50 parts by weight or less, the mechanical properties of the cured coating film are good. From the viewpoints of sensitivity and mechanical properties of the cured coating film, the more preferable blending amount of the photopolymerization initiator (D) is 2 to 100 parts by weight of the photosensitive resin (A1) or the photosensitive resin (A2). The range is 30 parts by weight.

  The resist ink composition of the present invention comprises the photosensitive resin (A1) or the photosensitive resin (A2), a heat-reactive curing agent (B), a diluent (C), and a photopolymerization initiator (D). It can be obtained by uniformly mixing by means of a main roll or a revolution / revolution type stirrer.

  Here, the blending amount of the photosensitive resin (A1) or the photosensitive resin (A2) is not particularly limited, but the effect of improving the sensitivity and the drying property at the time of preliminary drying becomes favorable. From the point which is excellent in the heat resistance and solvent resistance of hardened | cured material, 10 to 70 weight% is preferable in a resist ink composition, and it is preferable that it is the range used as 30 to 60 weight% especially.

  In the resist ink composition of the present invention, pigments, fillers, additives and the like used in the technical field as shown below can be used in combination as necessary. For example, organic pigments such as quinacridone, azo, and phthalocyanine; inorganic pigments such as titanium oxide, metal foil pigments, rust preventive pigments; barium sulfate, calcium carbonate, spherical fused silica, crushed fused silica, crystalline silica, alumina Fillers such as silicon nitride, aluminum hydroxide, carbon black, talc and clay; UV absorbers such as hindered amines, benzotriazoles and benzophenones; oxidations such as hindered phenols, phosphoruss, sulfurs and hydrazides Inhibitors; coupling agents such as silanes and titaniums; leveling agents such as fluorosurfactants; rheology control agents such as aerosils; pigment dispersants: anti-repellent agents; additives such as antifoaming agents . Moreover, reinforcing materials, such as glass fiber, glass cloth, and carbon fiber, can be contained as needed. Moreover, a flame retardant imparting agent can be added as necessary. Various flame retardants can be used as the flame retardant, such as halogen compounds such as decabromodiphenyl ether and tetrabromobisphenol A; phosphorus atom-containing compounds such as red phosphorus and various phosphate compounds; melamine or derivatives thereof Nitrogen atom-containing compounds; inorganic flame retardant compounds such as aluminum hydroxide, magnesium hydroxide, zinc borate and calcium borate can be exemplified.

  As a method of using the resist ink composition thus obtained, for example, screen printing, curtain coating method, roll coating method, spin coating method, dip coating method or the like is used on a printed circuit board to have a thickness of 10 to 150 μm (liquid film thickness). ) And then dried at 60-90 ° C. for 15-90 minutes to volatilize volatile components such as organic solvents (the coating and preliminary drying steps may be repeated several times) and dried Examples include a method in which a negative film having a desired mask pattern is brought into close contact with the coating film, and exposure is performed by irradiating with radiation such as ultraviolet rays or electron beams. Alternatively, the pattern may be directly exposed using a laser beam or the like. In this case, no mask pattern is required. Thereafter, by developing with a dilute alkaline aqueous solution as a developer, the coating film in the non-exposed area is removed, but the coating film in the exposed area remains unremoved because it is photocured. In this case, the dilute alkaline aqueous solution is generally 0.5 to 5% by weight of sodium carbonate aqueous solution or sodium hydroxide aqueous solution, but other alkaline solutions can also be used. Next, a cured product can be obtained by thermosetting with a hot air dryer or the like at 130 to 160 ° C. for 20 to 90 minutes.

  The resist ink composition of the present invention is preferably used for, for example, a solder resist or an interlayer insulating layer of a circuit board such as a printed wiring board.

  Hereinafter, the present invention will be described more specifically with reference to examples. Unless otherwise specified, the central part and% in the examples are based on weight.

Synthesis Example 1 [Synthesis of Photosensitive Resin (A1)]
2116 g of diethylene glycol monoethyl ether acetate, 2140 g (10.0 equivalents) of orthocresol novolac type epoxy resin [Dainippon Ink & Chemicals, EPICLON N-695, softening point 95 ° C., epoxy equivalent 214], 2 mol of ε-caprolactone Modified acrylic acid (manufactured by Toagosei Co., Ltd., Aronix M-5300, molecular weight 300) 3000 g (10.0 mol) and 2.6 g hydroquinone were charged, and heated and stirred at 100 ° C. to uniformly dissolve. Next, 15.4 g of triphenylphosphine was charged, heated to 110 ° C. and reacted for 2 hours, and further 5.1 g of triphenylphosphine was added, and the temperature was raised to 120 ° C. and reacted for further 14 hours. Into the obtained reaction liquid, 2116 g of aromatic hydrocarbon (Sorvesso 150), 1140 g (7.5 mol) of tetrahydrophthalic anhydride and 200 g (2.0 mol) of succinic anhydride were charged and reacted at 110 ° C. for 4 hours. It was. Furthermore, 426 g (3.0 mol) of glycidyl methacrylate was added to the obtained reaction liquid, and subsequently reacted at 115 ° C. for 4 hours to obtain a resin solution having a solid content acid value of 59 mg KOH / g and a solid content of 62%. This is designated as resin solution A1-1.

Synthesis Example 2 [Synthesis of photosensitive resin (A2)]
1557 g of diethylene glycol monoethyl ether acetate was charged with 2140 g (10.0 equivalents) of EPICLON N-695, 600 g (2.0 mol) of Aronix M-5300, 576 g (8.0 mol) of acrylic acid, and 1.7 g of hydroquinone, 100 The mixture was heated and stirred at 0 ° C. to dissolve uniformly. Next, 9.9 g of triphenylphosphine was added, heated to 110 ° C. and reacted for 2 hours, then 3.3 g of triphenylphosphine was further added, heated to 120 ° C., and reacted for another 12 hours. 1557 g of aromatic hydrocarbon (Sorvesso 150), 1140 g (7.5 mol) of tetrahydrophthalic anhydride and 200 g (2.0 mol) of succinic anhydride were charged into the obtained reaction liquid and reacted at 110 ° C. for 4 hours. It was. Furthermore, 426 g (3.0 mol) of glycidyl methacrylate was added to the obtained reaction solution, and the reaction was continued at 115 ° C. for 4 hours to obtain a resin solution having a solid content acid value of 86 mgKOH / g and a solid content of 62%. This is designated as resin solution A2-1.

Synthesis example 3 (same as above)
1488 g of diethylene glycol monoethyl ether acetate was charged with 2140 g of EPICLON N-695 (10.0 equivalents), 300 g of Aronics M-5300 (1.0 mol), 648 g (9.0 mol) of acrylic acid, and 1.5 g of hydroquinone, and 100 ° C. The mixture was heated and stirred to dissolve uniformly. Next, 9.3 g of triphenylphosphine was charged, heated to 110 ° C. and reacted for 2 hours. Then, 3.1 g of triphenylphosphine was added, heated to 120 ° C., and further reacted for 10 hours. The obtained reaction solution was charged with 1488 g of Solvesso 150, 1140 g (7.5 mol) of tetrahydrophthalic anhydride, and 200 g (2.0 mol) of succinic anhydride, and reacted at 110 ° C. for 4 hours. Furthermore, 426 g (3.0 mol) of glycidyl methacrylate was added to the obtained reaction liquid, and subsequently reacted at 115 ° C. for 4 hours to obtain a resin solution having a solid content acid value of 83 mgKOH / g and a solid content of 62%. This is designated as resin solution A2-2.

Synthesis example 4 (same as above)
1401 g of diethylene glycol monoethyl ether acetate, orthocresol novolac type epoxy resin [Dainippon Ink & Chemicals, EPICLON N-680, softening point 80 ° C., epoxy equivalent 212] 2120 g (10.0 equivalents), Aronix M-5300 600 g (2.0 mol), 576 g (8.0 mol) of acrylic acid, and 1.7 g of hydroquinone were charged, and the mixture was heated and stirred at 100 ° C. to be uniformly dissolved. Next, 9.9 g of triphenylphosphine was added, heated to 110 ° C. and reacted for 2 hours, then 3.3 g of triphenylphosphine was added, heated to 120 ° C., and further reacted for 12 hours. Into the obtained reaction solution, 1401 g of Solvesso 150 and 1064 g (7.0 mol) of tetrahydrophthalic anhydride were charged and reacted at 110 ° C. for 4 hours. Furthermore, 213 g (1.5 mol) of glycidyl methacrylate was added to the obtained reaction solution, and subsequently reacted at 110 ° C. for 4 hours to obtain a resin solution having a solid content acid value of 75 mgKOH / g and a solid content of 62%. This is designated as resin solution A2-3.

Synthesis example 5 (same as above)
Diethylene glycol monoethyl ether acetate 1575g, phenol novolak epoxy resin [Dainippon Ink Chemical Co., Ltd., EPICLON N-775, softening point 75 ° C, epoxy equivalent 188] 1880g (10.0 equivalent), Aronix M-5300 600g ( 2.0 mol), 576 g (8.0 mol) of acrylic acid, and 1.5 g of hydroquinone were charged, and the mixture was heated and stirred at 100 ° C. to uniformly dissolve. Next, 9.2 g of triphenylphosphine was charged, heated to 110 ° C. and reacted for 2 hours, then 3.1 g of triphenylphosphine was added, and the reaction was further performed for 12 hours by heating to 120 ° C. To the resulting reaction solution, 15575 g of Solvesso 150 and 1444 g (9.5 mol) of tetrahydrophthalic anhydride were charged, and the reaction was performed at 115 ° C. for 4 hours. Furthermore, 639 g (4.5 mol) of glycidyl methacrylate was added to the resulting reaction solution, and the reaction was continued at 115 ° C. for 4 hours to obtain a resin solution having a solid content acid value of 62 mgKOH / g and a solid content of 62%. This is designated as resin solution A2-4.

Synthesis example 6 (same as above)
Diethylene glycol monoethyl ether acetate 1467 g, EPICLON N-695 2140 g (10.0 equivalents), acrylic acid dimer [manufactured by Toagosei Co., Ltd., Aronix M-5600, molecular weight 152] 304 g (2.0 mol), acrylic acid 576 g (8.0 mol) and 1.5 g of hydroquinone were added, and the mixture was heated and stirred at 100 ° C. to uniformly dissolve. Next, 9.1 g of triphenylphosphine was charged, heated to 110 ° C. and reacted for 2 hours, then 3.0 g of triphenylphosphine was added, and the reaction was further performed for 12 hours by heating to 120 ° C. The obtained reaction solution was charged with 1467 g of Solvesso 150, 1140 g (7.5 mol) of tetrahydrophthalic anhydride, and 200 g (2.0 mol) of succinic anhydride, and reacted at 110 ° C. for 4 hours. Further, 426 g (3.0 mol) of glycidyl methacrylate was added to the obtained reaction solution, and the reaction was continued at 115 ° C. for 4 hours to obtain a resin solution having a solid content acid value of 84 mgKOH / g and a solid content of 62%. This is designated as resin solution A2-5.

Comparative Synthesis Example 1 (Production of Comparative Photosensitive Resin)
In 1103 g of diethylene glycol monoethyl ether acetate, 2120 g (10.0 equivalents) of EPICLON N-680, 720 g (10.0 mol) of acrylic acid, and 1.4 g of hydroquinone were charged, and heated and stirred at 100 ° C. to uniformly dissolve. Next, 8.5 g of triphenylphosphine was added, heated to 110 ° C. and reacted for 2 hours. Then, 2.8 g of triphenylphosphine was added, and the reaction was further performed for 10 hours. The obtained reaction solution was charged with 1103 g of Solvesso 150 and 760 g (5.0 mol) of tetrahydrophthalic anhydride, and reacted at 110 ° C. for 4 hours to obtain a resin solution having a solid content acid value of 87 mgKOH / g and a solid content of 62%. It was. This is designated as resin solution A′-1.

Comparative synthesis example 2 (same as above)
To 1,245 g of diethylene glycol monoethyl ether acetate, 2140 g (10.0 equivalents) of EPICLON N-695, 720 g (10.0 mol) of acrylic acid, and 1.4 g of hydroquinone were charged, and heated and stirred at 100 ° C. to uniformly dissolve. Next, 8.6 g of triphenylphosphine was charged, heated to 110 ° C. and reacted for 2 hours. Then, 2.9 g of triphenylphosphine was added, heated to 120 ° C., and further reacted for 10 hours. To the obtained reaction solution, 12245 g of Solvesso 150 and 988 g (6.5 mol) of tetrahydrophthalic anhydride were charged, and the reaction was performed at 110 ° C. for 4 hours. Furthermore, 213 g (1.5 mol) of glycidyl methacrylate was added to the obtained reaction solution, and subsequently reacted at 110 ° C. for 4 hours to obtain a resin solution having a solid content acid value of 76 mgKOH / g and a solid content of 62%. This is designated as resin solution A′-2.

Comparative synthesis example 3 (same as above)
In 1418 g of diethylene glycol monoethyl ether acetate, 2140 g (10.0 equivalent) of EPICLON N-695, 720 g (10.0 mol) of acrylic acid, and 1.4 g of hydroquinone were charged, and the mixture was heated and stirred at 100 ° C. to be uniformly dissolved. Next, 8.6 g of triphenylphosphine was charged, heated to 110 ° C. and reacted for 2 hours. Then, 2.9 g of triphenylphosphine was added, heated to 120 ° C., and further reacted for 10 hours. Into the obtained reaction solution, 14418 g of Solvesso 150, 1140 g (7.5 mol) of tetrahydrophthalic anhydride and 200 g (2.0 mol) of succinic anhydride were charged and reacted at 110 ° C. for 4 hours. Furthermore, 426 g (3.0 mol) of glycidyl methacrylate was added to the obtained reaction solution, and the reaction was continued at 115 ° C. for 4 hours to obtain a resin solution having a solid content acid value of 86 mgKOH / g and a solid content of 62%. This is designated as resin solution A′-3.

Synthesis Example 8 [Preparation of heat-reactive curing agent]
919 g of diethylene glycol monoethyl ether acetate was heated to 100 ° C., and 2140 g of EPICLON N-695 was uniformly dissolved to obtain a resin solution having a solid content of 70 wt%. This resin solution is designated as B-1.

Examples 1-6, Comparative Examples 1-3
Prepare a resist ink composition solution by blending a resist ink composition according to the blending composition shown in Tables 1 and 2 (numerical values are parts by weight), and mixing and dispersing with a rotating and rotating stirrer equipped with a cooling device. did. Table 3 shows the drying property, sensitivity, alkali developability and coating film performance of the resist ink composition thus obtained. The drying property, sensitivity, alkali developability and coating film performance of the resist ink composition were evaluated by the methods shown below. However, the coating film performance was such that a resist ink composition was applied to a polyimide film substrate to a thickness of 60 μm (before drying), pre-dried at 80 ° C. for 30 minutes, and then irradiated with ultraviolet rays at an exposure amount of 200 mJ / cm ^2. Then, using a 1% by weight aqueous sodium carbonate solution at 30 ° C., development treatment was carried out at a spray pressure of 2.0 kg / cm ² for 60 seconds, and after curing at 150 ° C. for 30 minutes, a cured coating film was prepared and evaluated. Went.

Test Method and Evaluation Method (1) Dryability The coating film was pre-dried at 80 ° C. for 30 minutes. Next, with the coating film cooled to room temperature, the solder mask pattern was brought into contact with the coating film surface, the negative film was peeled off, and the state was evaluated.
○: The film and the pattern do not adhere at all and can be easily peeled. Δ: The film can be peeled without leaving a trace, but has a slight adhesion feeling. ×: The film adheres to the solder mask pattern at the time of peeling.

(2) Sensitivity A 21-step tablet (manufactured by Kodak) was brought into close contact with the coating film after preliminary drying at 80 ° C. for 30 minutes, and an ultraviolet integrated intensity meter manufactured by Igraphic was used using an oak metal halide lamp exposure device. Irradiation exposure was performed with 200 mJ / cm ² of ultraviolet rays. Next, the number of the unexposed portions of the exposed portion after development for 60 seconds at a spray pressure of 2.0 kg / cm ² using a 1 wt% sodium carbonate aqueous solution at 30 ° C. is shown by numeral. Higher numbers indicate higher sensitivity.

(3) Development time A solder mask pattern was brought into close contact with the coating film after preliminary drying at 80 ° C. for 30 minutes, and was exposed to 200 mJ / cm ² of ultraviolet rays. Next, development was performed using a 1% by weight aqueous sodium carbonate solution at 30 ° C. and a spray pressure of 2.0 kg / cm ² . At the time of development, the development state of the unexposed part was visually determined with a magnifying glass every 15 seconds, and the time when the ink was completely removed and development was complete was defined as the development time.

(4) Thermal management width Each coating film whose pre-drying time was changed at intervals of 10 minutes from 80 ° C. for 20 minutes to 80 ° C. for 80 minutes was subjected to the same evaluation as (3) development time, and the maximum development possible in 60 seconds The pre-drying time (min) was defined as the thermal management width.

(5) Solder heat resistance According to the test method of JIS C 6481, the cured coating film was repeatedly immersed in a solder bath at 260 ° C. for 10 seconds, and the maximum number of times the appearance change did not appear was noted.

(6) Pencil hardness The cured coating film was tested according to the test method of JIS K 5400, and the highest hardness at which the coating film was not damaged was observed.

(7) Adhesiveness A 10 × 10 crosscut with a width of 1 mm was put into the cured coating film, and a peel test was performed with a cellophane tape, and the peeled state was visually observed.
○: No peeling is observed Δ: 1-10 peeling is observed x: 10 or more peeling

(8) Chemical resistance The state of the coating film after the cured coating film was immersed in 10% by weight hydrochloric acid for 30 minutes was evaluated.
○: No change at all ×: The film was swollen and peeled

(9) Solvent resistance The state of the coating film after the cured coating film was immersed in methylene chloride for 30 minutes was evaluated.
○: No change at all ×: The film was swollen and peeled

Claims (11)

Multifunctional epoxy resin (a1) and the following general formula (1)

(In the formula, n is an integer of 1 to 10, R ₁ is a hydrogen atom or a methyl group, R ₂ is a hydrocarbon group having 2 to 10 carbon atoms, and the hydrogen atom in the hydrocarbon group is Part or all may be substituted with a fluorine atom, a bromine atom or a chlorine atom.)
And a carboxyl group in an adduct obtained by addition reaction of a polybasic acid anhydride (a3) with a secondary hydroxyl group in a reaction product with the compound (a2) represented by formula (1) and an epoxy group-containing radical polymerizable unsaturated monomer. Containing a photosensitive resin (A1) obtained by reacting with an epoxy group in the body (a4), a heat-reactive curing agent (B), a diluent (C) and a photopolymerization initiator (D). A resist ink composition. The resist ink composition according to claim 1, wherein the compound (a2) is polylactone mono (meth) acrylate. The resist ink composition according to claim 1, wherein the acid value of the photosensitive resin (A1) is 30 to 150 mgKOH / g. The resist ink composition according to claim 1, wherein the polyfunctional epoxy resin (a1) is a novolac type epoxy resin. The resist ink composition according to claim 1, wherein the epoxy group-containing radical polymerizable unsaturated monomer (a4) is glycidyl (meth) acrylate. Multifunctional epoxy resin (a1) and the following general formula (1)

(In the formula, n is an integer of 1 to 10, R ₁ is a hydrogen atom or a methyl group, R ₂ is a hydrocarbon group having 2 to 10 carbon atoms, and the hydrogen atom in the hydrocarbon group is Part or all may be substituted with a fluorine atom, a bromine atom or a chlorine atom.)
A carboxyl group in an adduct obtained by addition reaction of a polybasic acid anhydride (a3) to a secondary hydroxyl group in a reaction product with the compound (a2) and (meth) acrylic acid (a5) represented by the formula: Photosensitive resin (A2) obtained by reacting with an epoxy group in the group-containing radically polymerizable unsaturated monomer (a4), a heat-reactive curing agent (B), a diluent (C), and photopolymerization initiation A resist ink composition comprising an agent (D). The resist ink composition according to claim 6, wherein the acid value of the photosensitive resin (A2) is 30 to 150 mgKOH / g. The resist ink composition according to claim 6, wherein the compound (a2) is polylactone mono (meth) acrylate. The resist ink composition according to claim 6, wherein the equivalent ratio (a2) :( a5) of the compound (a2) to the (meth) acrylic acid (a5) is in the range of 1:99 to 80:20. The resist ink composition according to claim 6, wherein the polyfunctional epoxy resin (a1) is a novolac type epoxy resin. The resist ink composition according to any one of claims 6 to 10, wherein the epoxy group-containing radical polymerizable unsaturated monomer (a4) is glycidyl (meth) acrylate.