JP6524579B2 - UV curable composition for inkjet etching resist - Google Patents

Description

  The present invention relates to an ultraviolet curable composition for an etching resist formed by inkjet.

  In recent years, photoresist inks that can be developed with a dilute alkaline aqueous solution are actively used particularly in the fields of printed wiring board manufacturing inks, flexible printed wiring board manufacturing inks, and the like. For example, a photosensitive curable composition can be used as a photoresist ink that can be developed with a dilute alkaline aqueous solution. However, when manufacturing a printed wiring board etc. using such a photoresist ink, it is necessary to prepare the mask film which drew the desired pattern in the case of exposure, and the development process is also required after exposing. In some cases, the process is complicated and the operation may be complicated. Therefore, in order to manufacture a printed wiring board etc. more simply, the method of apply | coating the curable composition for resists directly on a board | substrate using an inkjet system, and forming a resist pattern is also developed. Various compositions for such inkjet etching resists have also been proposed.

Patent No. 3997753 JP, 2012-245757, A

  Peeling of the coating film formed of the composition for inkjet etching resist is divided into a swelling and peeling type, a swelling and dissolving type, and a dissolution and peeling type. Among these, the dissolution peeling type resist is characterized in that since the coating film is peeled while being dissolved in the peeling solution, the residue is less likely to remain as compared with other methods. For example, Patent Documents 1 and 2 disclose resist compositions of the type in which peeling is performed by dissolution. However, in the case of the dissolution and peeling type resist, when the solubility in the peeling liquid becomes high, the hydrophilicity of the coating film becomes high, and the resistance to the etching liquid tends to be lowered. Therefore, when it is intended to increase the resistance to the etching solution, the hydrophobicity of the coating film is increased, and in this case, the solubility in the stripping solution tends to be lowered. Thus, there is a trade-off between solubility in the stripping solution and resistance to the etching solution, and it is difficult to simultaneously enhance both. In this regard, even the compositions disclosed in Patent Documents 1 and 2 are not sufficient.

  An object of the present disclosure is to provide a UV curable composition for an inkjet etching resist, which is excellent in both the solubility in a stripping solution and the resistance to an etching solution.

  The ultraviolet curable composition for inkjet etching resist of the present disclosure comprises (A) a (meth) acrylamide compound capable of forming a homopolymer soluble in water, and (B) a homopolymer capable of not dissolving in water (meth) It contains a acrylamide compound, (C) a photopolymerization initiator, and (D) a carboxyl group-containing compound having one ethylenically unsaturated group and at least one carboxyl group in one molecule.

  It is preferable that said ultraviolet curable composition for inkjet etching resists further contains the hydrophobic (meth) acrylic acid ester which has one ethylenic unsaturated group in 1 molecule (E).

  The carboxyl group-containing compound (D) preferably contains at least one selected from 2-acryloyloxyethyl hexahydrophthalic acid and 2-acryloyloxyethyl succinic acid.

  The photopolymerization initiator (C) preferably contains an acylphosphine oxide photopolymerization initiator.

It is preferable that the (meth) acrylamide compound of said (A) contains the compound represented by following formula (1). However, in Formula (1), R ¹ represents a hydrogen atom or a methyl group. Further, in the formula (1), R ² represents a hydrogen atom or an alkyl group, R ³ represents a hydrogen atom, an alkyl group or an alkoxyalkyl group, and the total carbon number of R ² and R ³ is 0 to 2 .

It is preferable that the (meth) acrylamide compound of said (B) contains the compound represented by following formula (2). However, in Formula (2), R ⁴ represents a hydrogen atom or a methyl group. R ⁵ represents a hydrogen atom or an alkyl group, and R ⁶ represents a hydrogen atom, an alkyl group or an alkoxyalkyl group. Alternatively, R ⁵ and R ⁶ form a cyclic ether structure in which two alkylene groups are connected via an oxygen atom. The total carbon number of R ⁵ and R ⁶ is 3 or more.

  The (meth) acrylamide compound of (A) preferably contains at least one selected from (meth) acrylamide, N, N-dimethyl (meth) acrylamide, and N-methyl (meth) acrylamide.

  The (meth) acrylamide compound of (B) is selected from N, N-diethyl (meth) acrylamide, N-isopropyl (meth) acrylamide, N-n-butoxymethyl (meth) acrylamide, 4- (meth) acryloyl morpholine It is preferable to include at least one of

  The content ratio of the (meth) acrylamide compound of (A) to the (meth) acrylamide compound of (B) is preferably 1: 1 to 1:10 by mass ratio.

  It is preferable that the above-mentioned ultraviolet curable composition for inkjet etching resist further contains (F) dye.

  The (F) dye preferably includes at least one dye selected from a dye having an anthraquinone skeleton and an amino group, a dye having a naphthalene skeleton and an amino group, and a dye having a phthalocyanine skeleton.

  The ultraviolet curable composition for an ink jet etching resist of the present disclosure is excellent in resistance to an etching solution and has good solubility in a peeling solution.

  The ultraviolet curable composition for inkjet etching resist (hereinafter also referred to as “ultraviolet curable composition”) of the present disclosure comprises (A) a (meth) acrylamide compound capable of forming a homopolymer soluble in water, and (B) water Containing a (meth) acrylamide compound capable of forming a homopolymer not soluble in water, (C) a photopolymerization initiator, and (D) one ethylenically unsaturated group and at least one carboxyl group in one molecule And a carboxyl group-containing compound.

  Both component (A) and component (B) are (meth) acrylamide compounds. However, they differ in the water solubility of the homopolymers. The water solubility of homopolymers is defined as the polymer water solubility.

  Here, in the present specification, (meth) acrylic generally refers to acrylic and methacrylic. For example, (meth) acrylamide generically refers to acrylamide and methacrylamide. That is, (meth) acrylamide is meant to include at least one of acrylamide and methacrylamide.

  The (meth) acrylamide compound of the component (A) can form a homopolymer soluble in water. That is, if only the (meth) acrylamide compound of the component (A) is polymerized, the polymer dissolves in water. The (meth) acrylamide compound of the component (A) is, as it were, a (meth) acrylamide compound having high polymer water solubility. However, in the ultraviolet curable composition, the component (A) does not polymerize alone but is polymerized together with other components.

  On the other hand, the (meth) acrylamide compound of the component (B) can form a homopolymer which is not soluble in water. That is, if only the (meth) acrylamide compound of the component (B) is polymerized, a polymer which is insoluble in water can be synthesized. The (meth) acrylamide compound of the component (B) is, as it were, a (meth) acrylamide compound having low polymer water solubility. However, in the ultraviolet curable composition, the component (B) is not polymerized alone, but is polymerized together with other components. The (meth) acrylamide compound itself of the component (B) may be dissolved in water.

Here, the polymer water solubility of (A) component and (B) component is judged based on technical common sense. In particular, it is determined whether a 20% aqueous solution of a homopolymer thermally polymerized in water at 80 ° C. for 1 hour under a catalyst maintains a uniform appearance at a temperature of 20 ° C. A uniform appearance means that precipitation does not occur, and may be cloudy. Alternatively, the monomer is mixed with a photopolymerization initiator to form a coating film having a film thickness of about 20 μm, and then all of the homopolymer coating film cured by ultraviolet light with an integrated light quantity of 400 mJ / cm ² dissolves in water at 20 ° C. It is decided by whether or not.

  By using the (meth) acrylamide compound of the component (A) and the (meth) acrylamide compound of the component (B) in combination, the resist formed from the ultraviolet curable composition is excellent in etching solution resistance and dissolution peelability. . Conventionally, in the case of the dissolution and peeling type resist, there is a trade-off between the solubility in the peeling liquid and the resistance to the etching liquid, and it has been difficult to simultaneously enhance both, but in the UV curable composition of the present disclosure, Both the components (A) and (B) can be simultaneously enhanced. The etching solution is generally acidic, and the resist of the ultraviolet curable composition of the present disclosure is excellent in acid resistance. The stripping solution is preferably an alkaline solution, and the resist of the ultraviolet curable composition of the present disclosure is excellent in the solubility in an alkaline solution.

  It is preferable that the (meth) acrylamide compound of (A) component contains the compound represented by following formula (1).

Here, in Formula (1), R ¹ represents a hydrogen atom or a methyl group. R ² represents a hydrogen atom or an alkyl group, R ³ represents a hydrogen atom, an alkyl group or an alkoxyalkyl group, and the total carbon number of R ² and R ³ is 0 to 2.

In the compounds represented by (meth) acrylamide compound of formula (1), the total number of carbon atoms of R ² and R ³ is a 0-2, a water-soluble homopolymer thereof is high.

  Examples of the (meth) acrylamide compound as the component (A) include (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N- (methoxy) Methyl) (meth) acrylamide is mentioned. These may be used alone or in combination of two or more.

  It is preferable that the (meth) acrylamide compound of (A) component contains at least 1 chosen from (meth) acrylamide, N, N- dimethyl (meth) acrylamide, and N- methyl (meth) acrylamide. When these components are used, it is easy to obtain a resist with high dissolution and releasability. These may be used alone or in combination of two or more.

  It is preferable that the (meth) acrylamide compound of (B) component contains the compound represented by following formula (2).

Here, in Formula (2), R ⁴ represents a hydrogen atom or a methyl group. In one aspect, R ⁵ represents a hydrogen atom or an alkyl group, and R ⁶ represents a hydrogen atom, an alkyl group or an alkoxyalkyl group. In another aspect, R ⁵ and R ⁶ form a cyclic ether structure in which two alkylene groups are connected via an oxygen atom. In any of these embodiments, the total carbon number of R ⁵ and R ⁶ is 3 or more.

  Examples of the (meth) acrylamide compound as the component (B) include N, N-diethyl (meth) acrylamide, N-isopropyl (meth) acrylamide, N-n-propyl (meth) acrylamide, N-cyclopropyl (meth) Acrylamide, N-n-butoxymethyl (meth) acrylamide, N-isobutoxymethyl (meth) acrylamide, 4- (meth) acryloyl morpholine, N-tertiary butyl (meth) acrylamide, N-tertiary octyl (meth) acrylamide Can be mentioned. These may be used alone or in combination of two or more.

The (meth) acrylamide compound of the component (B) is selected from N, N-diethyl (meth) acrylamide, N-isopropyl (meth) acrylamide, N-n-butoxymethyl (meth) acrylamide and 4- (meth) acryloyl morpholine It is preferable to include at least one of When these components are used, a resist having high acid resistance can be easily obtained. These may be used alone or in combination of two or more. Incidentally, 4- (meth) acryloyl morpholine, R ⁵ and R ⁶ of formula (2) corresponds to the compound to form a cyclic ether structure.

  In addition, the ultraviolet curable composition may also contain the (meth) acrylamide compound of the (A) component other than Formula (1), and the (meth) acrylamide compound of the (B) component other than Formula (2). As a (meth) acrylamide compound which does not belong to Formula (1) or Formula (2), for example, N-hydroxyethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, diacetone (meth) acrylamide And N, N'-methylenebisacrylamide. Among these, the (meth) acrylamide compound capable of forming a homopolymer soluble in water belongs to the component (A), and the (meth) acrylamide compound capable of forming a homopolymer not soluble in water is a component (B) Belongs.

  It is preferable that the (meth) acrylamide compound of (B) component is more than the (meth) acrylamide compound of (A) component. As a result, it is easy to obtain a resist having high dissolution and releasability while maintaining good coating film properties.

  The content ratio of the (meth) acrylamide compound of the component (A) to the (meth) acrylamide compound of the component (B) is preferably 1: 1 to 1:10 by mass ratio. By having the content ratio in this range, the dissolution peelability and the acid resistance increase in a well-balanced manner. The content ratio of the (meth) acrylamide compound of the component (A) to the (meth) acrylamide compound of the component (B) is more preferably 1: 2 to 1: 9 in mass ratio. The amount of the (meth) acrylamide compound of the component (B) may be three or more times the amount of the (meth) acrylamide compound of the component (A). The amount of the (meth) acrylamide compound of the component (B) may be 8 times or less or 6 times or less the amount of the (meth) acrylamide compound of the component (A).

  It is preferable that the (meth) acrylamide compound of (A) component is 1-20 mass% with respect to the ultraviolet curable composition whole quantity. When the content of the component (A) falls within this range, it is possible to obtain a resist having excellent dissolution and releasability. If the content of the polymerizable monomer of the component (A) is too small, the dissolution and removability may not be sufficient. If the content of the component (A) is too large, the acid resistance may not be sufficient. The content of the component (A) is more preferably 3 to 15% by mass, and still more preferably 4 to 10% by mass.

It is preferable that it is 10-70 mass% with respect to the ultraviolet curable composition whole quantity of the (meth) acrylamide compound of (B) component. When the content of the component (B) falls within this range, a resist excellent in acid resistance can be obtained, and in particular, sharp lines can be formed because generation of satellites is suppressed. Satellites are so-called paint splashes.
If the content of the polymerizable monomer of the component (B) is too small, the acid resistance may be insufficient. If the content of the component (B) is too large, the removability may not be sufficient. The content of the component (B) is more preferably 15 to 60% by mass, and still more preferably 20 to 55% by mass.

  In addition, it is preferable that the (meth) acrylamide compound total amount which united (A) component and (B) component is 20-80 mass% with respect to the ultraviolet curable composition whole quantity. Thereby, good curability is obtained. It is more preferable that the (meth) acrylamide compound total amount which united (A) component and (B) component is 30-70 mass% with respect to the ultraviolet curable composition whole quantity.

  Component (C) is a photopolymerization initiator. Examples of the photopolymerization initiator include acyl phosphine oxide photopolymerization initiator, alkylphenone photopolymerization initiator, titanocene photopolymerization initiator, oxime ester photopolymerization initiator, and cationic photopolymerization initiator. . Among these, an acyl phosphine oxide type photoinitiator is preferable. By using an acyl phosphine oxide type photoinitiator as a photoinitiator, the hardenability in a ultraviolet curable composition improves especially, and a coating film physical property improves. In addition, the acyl phosphine oxide type photopolymerization initiator is preferable also when the ultraviolet ray curable composition contains a dye. In that case, color loss is effectively suppressed. The reason for this is presumed to be that the curing of the colored coating proceeds well, so that the resistance to ozone, which is the causative substance of color loss due to photooxidation, is improved, and the weather resistance is also improved.

  The ultraviolet curable composition may contain only an acyl phosphine oxide type photoinitiator as a photoinitiator. The ultraviolet curable composition may contain, as a photopolymerization initiator, an acyl phosphine oxide photopolymerization initiator and another photopolymerization initiator. However, when the photopolymerization initiator contains a plurality of types, it is preferable that the content of the acylphosphine oxide photopolymerization initiator is larger than that of the other photopolymerization initiators.

  Examples of acyl phosphine oxide photopolymerization initiators include 2,4,6-trimethyl benzoyl diphenyl phosphine oxide, 2,6-dimethoxy benzoyl diphenyl phosphine oxide, 2,6-dichloro benzoyl diphenyl phosphine oxide, 2 Monoacyl phosphine oxides such as 2,4,6-trimethyl benzoyl phenyl phosphine acid methyl ester, 2-methyl benzoyl diphenyl phosphine oxide, pivaloyl phenyl phosphine acid isopropyl ester, and bis- (2,6-dichloro) Benzoyl) phenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -2,5-dimethylphenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -4-pro Phenyl phosphine oxide, bis- (2,6-dichlorobenzoyl) -1-naphthyl phosphine oxide, bis- (2,6-dimethoxy benzoyl) phenyl phosphine oxide, bis- (2, 6-dimethoxy benzoyl)- 2,4,4-trimethylpentyl phosphine oxide, bis- (2,6-dimethoxybenzoyl) -2,5-dimethylphenyl phosphine oxide, bis (2,4,6-trimethyl benzoyl) -diphenyl phosphine oxide, Examples include bisacyl phosphine oxides such as (2,5,6-trimethyl benzoyl) -2,4,4-trimethylpentyl phosphine oxide. These may be used alone or in combination of two or more.

  The content of the photopolymerization initiator is preferably 1 to 40% by mass with respect to the total amount of the ultraviolet curable composition. When the content of the photopolymerization initiator is in this range, a good cured coating can be obtained. If the content of the photopolymerization initiator is too small, the curability may not be sufficient. If the content of the photopolymerization initiator is too large, the ink jet application may not be easy. The content of the photopolymerization initiator is more preferably 3 to 30% by mass, and further preferably 10 to 25% by mass. The content of the photopolymerization initiator may be 15% by mass or more. The content of the photopolymerization initiator may be 20% by mass or less.

  The carboxyl group-containing compound of component (D) has one ethylenically unsaturated group in one molecule. The ethylenically unsaturated group allows the component (D) to be photopolymerized. In addition, the carboxyl group-containing compound of the component (D) has at least one carboxyl group in one molecule. The component (D) can be dissolved in alkali due to the carboxyl group. The carboxyl group-containing compound of component (D) preferably has only one ethylenically unsaturated group in one molecule. Thereby, good solubility is obtained. The carboxyl group-containing compound of the component (D) has one or more carboxyl groups in one molecule, and may have only one or two or three, for example. It may have or may have more.

  The component (D) is a polymerizable monomer (monomer) and contributes to the polymerization. In the present specification, a polymerizable monomer means a monomer that is photopolymerized. Unsaturated carbon-carbon bonds can exhibit photopolymerizability. By using the carboxyl group-containing compound of component (D), the solubility in alkali is improved. In addition, the component (D) can effectively suppress the decoloring of the dye. The reason is presumed to be that the basic substituent of the dye and the carboxyl group of the component (D) have an interaction. It is thought that the presence of a carboxyl group contributes to the suppression of color loss and the improvement of acid resistance. By using the component (D), a good coating can be obtained.

  Examples of the component (D) include phthalic acid-based (meth) acrylic acid esters and succinic acid-based (meth) acrylic acid esters. As such (meth) acrylic acid ester, for example, 2- (meth) acryloyloxyethyl hexahydrophthalic acid, 2- (meth) acryloyloxyethyl succinic acid, 2- (meth) acryloyloxyethyl-phthalic acid The acids include 2- (meth) acryloyloxyethyl tetrahydrophthalic acid. These may be used alone or in combination of two or more. In particular, a good ultraviolet curable composition can be obtained by using two or more of these in combination. The combined use of a phthalic acid-based (meth) acrylic acid ester and a succinic acid-based (meth) acrylic acid ester is particularly preferable in order to form a good coating film. As ethylenic unsaturated compounds having other carboxyl groups, (meth) acrylic acid, maleic acid, ω-carboxy-polycaprolactone (n ≒ 2) monoacrylate, crotonic acid, cinnamic acid, β-carboxyethyl acrylate, Maleic acid mono [2- (meth) acryloyloxyethyl] can be mentioned. Thus, the ethylenically unsaturated compound having a carboxyl group may be a (meth) acrylic acid ester having a carboxyl group, or may be a (meth) acrylic acid into which a substituent has been introduced, It may be a compound having another structure.

  The carboxyl group-containing compound of component (D) preferably contains at least one selected from 2-acryloyloxyethyl hexahydrophthalic acid and 2-acryloyloxyethyl succinic acid. In this case, a coating film having good acid resistance and dissolution and removability can be easily obtained.

  It is preferable that content of the carboxyl group-containing compound of (D) component is 1-50 mass% with respect to the ultraviolet curable composition whole quantity. When the content of the component (D) falls within this range, a good cured coating can be obtained. If the content of the component (D) is too small, there is a possibility that the dissolution and removability of the etching resist can not be maintained. If the content of the component (D) is too large, the ink jet application may not be easy. The content of the component (D) is more preferably 5 to 40% by mass, and still more preferably 8 to 35% by mass. In order to facilitate inkjet coating, the content of the component (D) is more preferably 30% by mass or less, and still more preferably 25% by mass or less. In order to enhance the dissolution and removability, the content of the component (D) is more preferably 10% by mass or more, and still more preferably 14% by mass or more.

  It is preferable that the ultraviolet curable composition for inkjet etching resists further contains the hydrophobic acrylic acid ester which has one ethylenically unsaturated group in 1 molecule of (E). Thereby, the acid resistance of the resist can be further improved while maintaining the dissolution and removability of the resist.

  Examples of the (meth) acrylate ester of the component (E) include propyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, tertiary butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, n-decyl (meth) acrylate, isodecyl (meth) acrylate, lauryl (meth) acrylate, myristyl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, isobonyl (meth) Straight-chain, branched or alicyclic alkyl (meth) acrylates such as acrylate, cyclohexyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate; methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate ) Aromatic (meth) acrylates such as acrylate, phenoxyethyl (meth) acrylate, benzyl (meth) acrylate, and ethylene glycol-based (meth) acrylates such as diethylene glycol mono (meth) acrylate; Glycerol-based (meth) acrylates such as meta) acrylate may be mentioned. These may be used alone or in combination of two or more.

  As the (meth) acrylic acid ester of the component (E), one or more selected from phenoxyethyl (meth) acrylate and isobonyl (meth) acrylate is particularly preferable. These acrylic esters make it easier to form a cured coating having a good coating hardness.

  It is preferable that the ultraviolet curable composition for inkjet etching resists contains (F) dye. As a result, the resist is colored, which enhances the visibility of the resist. The ink colored with the dye cures to form a coating, and the resist pattern becomes clear. Dyes function as colorants.

  The dye of the component (F) preferably contains at least one dye selected from a dye having an anthraquinone skeleton and an amino group, a dye having a naphthalene skeleton and an amino group, and a dye having a phthalocyanine skeleton. The use of a dye having an anthraquinone skeleton and an amino group, a dye having a naphthalene skeleton and an amino group, and a dye having a phthalocyanine skeleton suppresses color loss. These dyes are relatively rigid in backbone. Therefore, it is presumed that the effect of suppressing color loss is high.

  Examples of dyes having an anthraquinone skeleton and an amino group include Solvent Red 122 and Solvent Blue 35.

  The structural formula of the solvent red 122 is shown below.

  The structural formula of solvent blue 35 is shown below.

  Examples of the dye having a naphthalene skeleton and an amino group include Solvent Blue 5 and Basic Blue 7.

  The structural formula of Solvent Blue 5 is shown below.

  The structural formula of Basic Blue 7 is shown below.

  Examples of the dye having a phthalocyanine skeleton include Direct Blue 87.

  The structural formula of direct blue 87 is shown below.

  It is preferable that content of said dye is 0.01-3 mass% with respect to the ultraviolet curable composition whole quantity. When the content of the dye falls within this range, a colored cured film can be obtained and the acid resistance is improved. When the content of the dye decreases, the colorability may not be sufficient. When the content of the dye increases, the curability may not be sufficient. The content of the dye is more preferably 0.03 to 2% by mass, and still more preferably 0.05 to 1% by mass. The content of the dye may be 0.1% by mass or more. The content of the dye may be 0.5% by mass or less.

  Examples of the dye that does not correspond to any of the dye having an anthraquinone skeleton and an amino group, the dye having a naphthalene skeleton and an amino group, and the dye having a phthalocyanine skeleton include Acid Blue 9 and the like. It has been confirmed that in a coating film using only Acid Blue 9, color loss is likely to occur.

  The ultraviolet curable composition may contain, as a dye, a dye having an anthraquinone skeleton and an amino group, a dye having a naphthalene skeleton and an amino group, and a dye other than a dye having a phthalocyanine skeleton. However, it is preferable that the dye having an anthraquinone skeleton and an amino group, the dye having a naphthalene skeleton and an amino group, and the dye having a phthalocyanine skeleton have a larger content than the other dyes. The dyes may be used alone or in combination of two or more.

  The ultraviolet curable composition for inkjet etching resists may contain an appropriate component other than the said (A)-(F) component. For example, the ultraviolet curable composition for inkjet etching resist may contain polymerizable monomers, additives, and organic solvents other than the above.

  As the polymerizable monomer, a compound having a carbon-carbon double bond in the molecule can be used. As a polymerizable monomer, for example, styrene, o-vinyltoluene, m-vinyltoluene, p-vinyltoluene, α-methylstyrene, o-hydroxystyrene, m-hydroxystyrene, p-hydroxystyrene, o-hydroxy-α- Vinyl aromatic compounds such as methylstyrene, m-hydroxy-α-methylstyrene, p-hydroxy-α-methylstyrene, p-vinylbenzyl alcohol, etc .; maleimide, N-benzyl maleimide, N-phenyl maleimide, N-cyclohexyl maleimide And maleimides; vinyl acetate, vinyl ethers, (meth) allyl alcohol, vinylidene cyanide, vinyl chloride, vinylidene chloride, vinyl pyrrolidone, (meth) acrylonitrile. These may be used alone or in combination of two or more.

  It is preferable that the ultraviolet curable composition for inkjet etching resist does not contain the compound which has 2 or more of ethylenic unsaturated groups in 1 molecule. Thereby, the dissolution and removability of the resist is enhanced. In this case, the UV curable composition for inkjet etching resist may contain only monofunctional monomers and may not contain polyfunctional monomers. Monofunctional means that there is one ethylenically unsaturated group in the molecule, and polyfunctional means that there are two or more ethylenically unsaturated groups in the molecule. Conventionally, a coating film formed only of a monofunctional monomer has a problem in that the curability is poor and the water resistance and acid resistance are also poor. However, in the ultraviolet curable composition for inkjet etching resist of the present disclosure, (A These problems are ameliorated by the combination of the component (B) and the component (B).

  It is preferable that the ultraviolet curable composition for inkjet etching resist does not contain a solvent. Thereby, no volatile component is present. This can give the property of being VOC free (without volatile organic compounds). When any one or more of the above components are liquid, the ultraviolet curable composition for an inkjet etching resist can be liquid even without a solvent.

  In addition, the ultraviolet curable composition for inkjet etching resists may be comprised only with said (A)-(F) component, and may be comprised only with said (A)-(E) component, and said You may be comprised only with (A)-(D) component.

  It is preferable that the ultraviolet curable composition for inkjet etching resists is a liquid. Thus, the coating can be easily performed by the ink jet coater. The ultraviolet curable composition for inkjet etching resist may have a solid component dissolved or dispersed in a liquid component.

  It is preferable that the ultraviolet curable composition for inkjet etching resists is 40 mPa * s or less in viscosity in 25 degreeC. Thereby, the coating can be satisfactorily performed by the ink jet coater. In ink jet coating, the ink is usually heated and discharged. At this time, the ink is heated to a temperature such that the viscosity is about 10 mPa · s. When the viscosity at 25 ° C. exceeds 40 mPa · s, it is required to raise the temperature of the ink at the time of application, which may lower the efficiency. In addition, when the viscosity at 25 ° C. exceeds 40 mPa · s, the pattern of the coating film formed by inkjet coating tends to be unclear. Therefore, it is preferable that the viscosity at 25 ° C. be 40 mPa · s or less. The ultraviolet curable composition for an inkjet etching resist preferably has a viscosity of 30 mPa · s or less at 25 ° C., more preferably 25 mPa · s or less, and still more preferably 20 mPa · s or less .

  It is preferable that the ultraviolet curable composition for inkjet etching resists is 5 mPa * s or more in viscosity in 25 degreeC. As a result, it is possible to suppress the spillage of the ink from the discharge nozzle during the inkjet application. It is more preferable that the ultraviolet curable composition for inkjet etching resists has a viscosity of 8 mPa · s or more at 25 ° C. The viscosity of the ultraviolet curable composition for inkjet etching resist can be measured with a B-type viscometer or the like.

  The ultraviolet curable composition for inkjet etching resist is preferably non-aqueous. Non-aqueous means that it does not contain water. Water inhibits the curability, so that the ultraviolet curable composition for an ink jet etching resist does not contain water, whereby a coating film with good curability can be obtained. In addition, that the ultraviolet curable composition for inkjet etching resists is non-aqueous means that water is not mix | blended actively, and the ultraviolet curable composition for inkjet etching resists has hygroscopicity. It is also non-aqueous when it contains a small amount of water due to the material. However, in the case of a non-aqueous system, the content of water detected in the ultraviolet curable composition is preferably 1% by mass or less.

  The ultraviolet curable composition for inkjet etching resists can be prepared by mix | blending predetermined amounts the component of said (A)-(F), and the additional component added as needed. At the time of this blending, if necessary, a diluting solvent such as alcohols and ketones may be added or may not be added. The liquid raw material can have a function as a solvent. In the case of no solvent, no volatile component is present. This can give the property of being VOC free (without volatile organic compounds).

  For example, a conductor pattern can be formed by using the above-described ultraviolet curable composition for an inkjet etching resist. A printed wiring board can be manufactured by formation of a conductor pattern. The ultraviolet curable composition for inkjet etching resist can be applied on a substrate by a direct writing method. With the direct drawing method, the resist ink layer has a desired shape by applying a resist ink onto a substrate by discharging an ultraviolet curable composition for inkjet etching resist (hereinafter, also referred to as “resist ink”) from a nozzle. It means to form according to. If the desired shape is a wiring shape, it becomes possible to form a pattern of wiring.

  In the above-described direct drawing method, for example, a generally commercially available inkjet coating device can be used. Specifically, the resist ink prepared as the etching resist ink may be discharged toward the substrate using a piezoelectric inkjet head to form a resist ink layer on the substrate. In this case, it is preferable to heat the resist ink to such a temperature that the viscosity is about 10 mPa · s, in that the resolution is further improved. The heating temperature may be, for example, in the range of 25 to 60 ° C.

  An appropriate substrate can be used as the substrate. As a board | substrate, a resin substrate, a ceramic substrate, a metal substrate etc. are mentioned, for example. An insulating substrate may be used as the substrate. Alternatively, a laminate having a conductor may be used as the substrate. A copper-clad laminate is exemplified as the laminate.

After a resist ink is applied by inkjet coating to form a patterned resist ink layer, a curing process is performed. For example, the resist ink layer may be irradiated with ultraviolet light directly or indirectly to form a cured coating film. For irradiation with ultraviolet light, for example, a chemical lamp, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a xenon lamp or a metal halide lamp, an LED-UV lamp or the like may be used. Further, in the curing step, in addition to ultraviolet rays, electron beams and the like can also be adopted, and there is no particular limitation as long as it is an active energy ray having an energy quantum that can polymerize or crosslink molecules such as monomers. The ultraviolet irradiation dose is not particularly limited, but may be, for example, in the range of 100 to 1000 mJ / cm ² .

In addition, after forming a cured coating film as described above, it is preferable to additionally irradiate ultraviolet light, and in this case, the resist ink can be cured more reliably, and unreacted substances can be made less likely to remain. . In the case of additionally irradiating ultraviolet light, the total amount of ultraviolet irradiation (the sum of the original irradiation and the additional irradiation) may be, for example, in the range of 1000 to 3000 mJ / cm ² .

  In the case of using a substrate having a conductive layer of metal or the like, after conducting the above-mentioned curing treatment, a patterned conductor can be easily formed on the substrate by passing through the etching treatment step. In the etching step, the conductive layer is partially removed using, for example, an etching solution. Thereby, a conductive layer having the same pattern as the resist pattern is formed.

  The resist ink (ultraviolet curable composition for inkjet etching resist) of the present disclosure is a dissolution and release type. In the dissolution and peeling type, the resist ink layer is peeled while being dissolved. The dissolution and release type resist ink almost eliminates the problem of the reattachment of the exfoliation piece which can occur in the swelling and release type. In addition, the dissolution and release type resist ink is less likely to cause a problem that a residue is generated in the uneven portion of the base material which can be generated in the swelling and release type and the swelling and dissolution type. Therefore, the dissolution and release type resist ink can form a resist ink layer with good releasability.

  The resist ink layer can be dissolved and peeled using a resist dissolving and peeling liquid. In the dissolution and peeling step, the resist ink layer, that is, the cured coating film formed by curing the ultraviolet curable composition for inkjet etching resist is dissolved in the resist dissolution and peeling liquid and may be peeled from the adhesive surface.

  The resist dissolving and peeling liquid is preferably an alkaline solution. The alkaline solution is preferably an alkaline aqueous solution. Thereby, the dissolution and peeling can be easily performed. For example, an aqueous solution of sodium hydroxide can be used as a resist dissolving and peeling solution. The concentration of sodium hydroxide is preferably 0.01 to 5%. The concentration of sodium hydroxide is particularly preferably 0.5 to 3%. In that case, the dissolution and peeling will be good. As the alkaline solution, an organic solvent containing an alkaline component may be used, or an alkaline aqueous solution containing an organic solvent may be used.

  As a method of dissolving and peeling the cured coating film, a method of immersing, a method of dissolving and peeling by spray coating, a method of irradiating ultrasonic waves after immersion, and the like can be used. In the case of dissolving and peeling by a method of immersion, for example, it may be immersed in a resist dissolving and peeling solution at 20 to 60 ° C. for 30 seconds to 10 minutes. Such an operation may be performed only once, or the same operation may be performed multiple times.

  As described above, the resist ink layer is dissolved and peeled, whereby a conductive layer having a desired pattern can be obtained. The patterned conductive layer formed through such a process can be used as a wired circuit conductor.

  The resist ink layer can exhibit excellent acid resistance. For example, the resist ink layer is less likely to peel off in the metal etching solution. The etchant is generally acidic. The resist ink layer may have a good hardness. For example, the resist ink layer can have a high pencil hardness.

  Since the above-mentioned ultraviolet curable composition for ink jet etching resist is suitable for ink jet coating, a good resist pattern can be formed by coating with an ink jet coater. Therefore, a fine conductor pattern can be formed well. The coating film formed by curing the above-mentioned ultraviolet curable composition for inkjet etching resist can be easily dissolved and peeled off by an aqueous alkaline solution. Thus, useful resists are provided.

  Thus, the ultraviolet curable composition for inkjet etching resist is useful for manufacture of a printed wiring board. The ultraviolet curable composition for inkjet etching resist can also be used for forming a glass pattern or for forming a ceramic pattern. Furthermore, the ultraviolet curable composition for inkjet etching resist can be used as a wiring protection material. Also, UV curable compositions for ink jet etching resists are useful in the manufacture of nameplates. In this case, a UV curable composition for inkjet etching resist is used as a decoration application. In these productions, for example, a resist ink layer is formed in a pattern on a metal layer of a substrate having a metal layer, and the metal layer is etched to form a patterned metal. As described above, after the formation of the pattern-like metal, the resist ink layer is dissolved and peeled off.

  Examples will be described below. The UV curable compositions for ink jet etching resists of the present disclosure are not limited to these examples.

(Examples 1 to 18, Comparative Examples 1 to 3)
According to the composition shown in Table 1, the ultraviolet curable composition (resist ink) for inkjet etching resists of Examples and Comparative Examples was prepared. Details of the raw materials are shown below.

[(A) component: (meth) acrylamide, but the homopolymer is soluble in water]
・ Methacrylamide (Mitsui Chemical "Methacrylamide")
・ N, N-dimethyl acrylamide ("DMAA" made by KJ Chemical)
[(B) component: (meth) acrylamide, but the homopolymer does not dissolve in water]
・ N, N-diethyl acrylamide ("DEAA" made by KJ Chemical)
-N-isopropyl acrylamide ("NIPAM" made by KJ Chemical)
4-Acryloyl morpholine ("ACMO" manufactured by KJ Chemical)
・ N-n-butoxymethyl acrylamide (“NBMA” manufactured by MRC Unitech)
[(C) component: photopolymerization initiator]
・ Trimethyl benzoyl diphenyl phosphine oxide ("IRGACURE TPO" made by BASF, an acyl phosphine oxide type photoinitiator)
・ Bis (2,4,6-trimethyl benzoyl) -phenyl phosphine oxide ("IRGACURE 819" made by BASF, an acyl phosphine oxide type photoinitiator)
[(D) component: carboxyl group-containing compound]
-2-acryloyloxyethyl hexahydrophthalic acid (manufactured by Kyoeisha "Light Acrylate HOA-HH")
-2-acryloyloxyethyl succinic acid (manufactured by Kyoeisha "Light Acrylate HOA-MS")
[(E) component: hydrophobic acrylic ester]
・ Phenoxyethyl acrylate (Osaka Organic Chemical Co., Ltd. "Biscoat 192")
・ Isobonyl acrylate ("Light acrylate IB-XA" manufactured by Kyoeisha)
[(F) component: dye]
Solvent Blue 5 (Oil Blue 613, manufactured by Orient Chemical Co., Ltd.)
・ Basic Blue 7 (Hodotani Chemical "Victor Pure Blue BOH")
Solvent Blue 35 (Oil Blue 2N, manufactured by Orient Chemical Co., Ltd.)
・ Direct Blue 87 (Orient Chemical "Barifast Blue 1621")
・ Solvent Red 122 (BASF "Orazole Red 395")
In addition, the numerical value of the compounding composition of Table 1 has shown the mass part.

[Preparation]
The said raw material was mix | blended by the compounding ratio of Table 1, the resist ink was obtained by heating to 60 degreeC and stirring for 60 minutes.

[viscosity]
The viscosity of the resist ink at 25 ° C. was measured with a B-type viscometer (BL type, No. 1 rotor, 60 rpm, manufactured by Tokyo Keiki Co., Ltd.). Further, the resist ink was heated, and the temperature at which the viscosity became 10 mPa · s was measured.

[Production of test article]
The test substrate was produced by the following method. The application of the resist ink was performed using an inkjet coater (MJP 2013 KI-DU manufactured by Microcrafts Co., Ltd.). The resist ink was charged into the ink jet tank. Next, the temperature was set so that the viscosity of the resist ink was 10 mPa · s, and the resist ink was applied on a stainless steel plate (SUS 304) so as to have a film thickness of about 20 μm. After coating, UV curing (total light intensity: 400 mJ / cm ² (UV-350 measurement made by Oak Manufacturing Co., Ltd.)) was performed using a metal halide lamp made by Eye Graphics Co., Ltd. As an application | coating pattern, it carried out by the following two patterns.
-Application pattern 1: Solid coating of range 20 mm x 70 mm.
Application pattern 2: comb shape (line width 120 μm, space width 120 μm).

[Color loss]
With respect to the test substrate of application pattern 1, the coating film color was visually confirmed to confirm whether the color was lighter than that of the coating before the ultraviolet irradiation (color loss at 400 mJ / cm ² ). Further, after the color tone confirmation, by irradiating (total 2000 mJ / cm ²⁾ with ultraviolet light added in 1600 mJ / cm ^2, (decoloration at 2000 mJ / cm ²⁾ it was confirmed coating color. The color loss was judged according to the following criteria.
○: No change in color tone.
Δ: Slightly faded (color disappears)
X: The color completely disappears and it becomes colorless.

[hardness]
About the test substrate of application pattern 1, according to the test method of JIS K5600-5-4 on coating film hardness, the highest hardness not scratched by Mitsubishi Uni's pencil (Mitsubishi Pencil Co., Ltd.) is the coating hardness (pencil hardness) And

[Acid resistance (etching solution resistance)]
The test substrate of application pattern 1 was immersed in an aqueous solution of ferric chloride at 40 ° C. for 60 minutes, washed with water, dried, and then subjected to a tape adhesion test. In the tape adhesion test, the state of peeling of the coating film after the peeling test with the cellophane adhesive tape was visually determined according to the following criteria.
◎: No peeling occurred.
○: No peeling occurred, but some discoloration occurred.
Δ: Partial peeling occurred.
X: Peeling occurred on the entire surface.

[Alkali dissolution and removability]
The test substrate of application pattern 1 was immersed in a 1% aqueous solution of sodium hydroxide at 30 ° C., and the dissolution and peeling of the coating film were visually confirmed, and judged according to the following criteria.
○: Dissolving and peeling in less than 60 seconds.
Δ: Dissolving and peeling in 60 seconds or more.
X: Swelling and peeling were performed without dissolution and peeling.
× ×: did not peel off.

[Ink jet coatability (line clarity)]
With respect to the test substrate of application pattern 2, the line shape of the coating film was observed with a microscope and judged according to the following criteria.
○: Sharp lines are formed, and satellites and the like are not scattered.
Δ: A line was formed. However, slight thickening and thinning of the line, and scattering of slight satellites, etc. can be seen (about an extent that does not affect pattern formation).
X: Although discharge is performed, the line is largely crushed.

[result]
As shown in Table 1, the coating obtained from the resist ink of the example is superior in dissolution and removability to the coating obtained from the resist ink of the comparative example, and the physical properties as an inkjet etching resist are better. Is obtained.

Claims (9)

(A) (meth) acrylamide compound capable of forming a homopolymer soluble in water,
(B) (meth) acrylamide compounds capable of forming homopolymers that are not soluble in water,
(C) a photopolymerization initiator,
(D) A carboxyl group-containing compound having one ethylenically unsaturated group and at least one carboxyl group in one molecule,
Contain,
The (meth) acrylamide compound of (A) contains at least one selected from (meth) acrylamide, N, N-dimethyl (meth) acrylamide, and N-methyl (meth) acrylamide.
The (meth) acrylamide compound of (B) is selected from N, N-diethyl (meth) acrylamide, N-isopropyl (meth) acrylamide, N-n-butoxymethyl (meth) acrylamide, 4- (meth) acryloyl morpholine Containing at least one of
UV curable composition for inkjet etching resist.   The ultraviolet curable composition for inkjet etching resists according to claim 1, further comprising (E) a hydrophobic (meth) acrylic acid ester having one ethylenically unsaturated group in one molecule.   The inkjet etching according to claim 1 or 2, wherein the carboxyl group-containing compound of (D) contains at least one selected from 2-acryloyloxyethyl hexahydrophthalic acid and 2-acryloyloxyethyl succinic acid. UV curable composition for resists.   The ultraviolet curable composition for inkjet etching resists according to any one of claims 1 to 3, wherein the photopolymerization initiator (C) contains an acyl phosphine oxide photopolymerization initiator. The ultraviolet curable composition for inkjet etching resists of any one of Claims 1 to 4 in which the (meth) acrylamide compound of said (A) contains the compound represented by following formula (1).

In formula (1), R ¹ represents a hydrogen atom or a methyl group,
R ² represents a hydrogen atom or an alkyl group, R ³ represents a hydrogen atom, an alkyl group or an alkoxyalkyl group, and the total carbon number of R ² and R ³ is 0 to 2. The ultraviolet curable composition for inkjet etching resists of any one of Claims 1-5 in which the (meth) acrylamide compound of said (B) contains the compound represented by following formula (2).

In formula (2), R ⁴ represents a hydrogen atom or a methyl group,
R ⁵ represents a hydrogen atom or an alkyl group, R 6 represents a hydrogen atom, an alkyl group or an alkoxyalkyl group, or R ⁵ and R ⁶ form a cyclic ether structure in which two alkylene groups are connected via an oxygen atom And
The total carbon number of R ⁵ and R ⁶ is 3 or more. The content ratio of the (meth) acrylamide compound of the (meth) acrylamide compound of (A) (B) is a mass ratio, 1: 1 to 1: 10, any one of claims 1 to 6 1 The ultraviolet curable composition for inkjet etching resists as described in a term. The ultraviolet curable composition for inkjet etching resists according to any one of claims 1 to 7 , further comprising (F) a dye. The dye according to claim 8 , wherein the dye (F) includes at least one dye selected from a dye having an anthraquinone skeleton and an amino group, a dye having a naphthalene skeleton and an amino group, and a dye having a phthalocyanine skeleton. UV curable composition for inkjet etching resist.