JP5740209B2 - Aqueous inkjet ink composition for etching resist - Google Patents

Description

  The present invention relates to an ink composition used for an etching resist, and more particularly to an aqueous inkjet ink composition for an etching resist that is an aqueous etching resist that can be printed by an inkjet printing method.

  Etching is the formation of a protective film (resist) that can withstand chemicals (corrosive solution, etchant) on the necessary parts of the material having a corrosive layer (for example, metals such as copper and zinc, resin) on the surface. This is a method of performing an anticorrosion treatment and then removing unnecessary portions with chemicals, and thereafter, the protective film is removed and development is performed. In this case, development with an alkaline solution is generally used. However, by removing the protective film with such a chemical, a corrosive layer remains only on the protected portion, and a desired image can be formed on the material. To. By using this method, it is possible to create elaborate characters, images, circuits, patterns, etc. on various types of materials, but in recent years, the use of this technique has spread to a wide range of fields.

  The technique using such an etching method is used as a technique for image formation or pattern formation in various fields such as metal processing, electronic circuits, printed circuit boards, plate making, semiconductor fields, and color filters. In particular, from the actual situation that the miniaturization has progressed with the rapid development of information-oriented devices in recent years, and for the purpose of responding to high design properties such as metal plates, image formation and pattern formation, There is a demand for an etching method that is fine and multilayered, and that enables the formation of delicate and fine line drawings. For this reason, the inkjet printing method is also used in the etching method so that finer line drawings can be printed than the conventional spin coating and slit coating methods used for screen printing and photolithography. Being started. Here, the resist ink used in the inkjet printing method is an organic solvent system (for example, see Patent Documents 1 and 2), an ultraviolet curable ink (for example, see Patent Documents 3 and 4), etc., but resource saving, From the viewpoint of energy saving, environmental friendliness and safety, development of water-based ink is required.

Japanese Patent Laid-Open No. 9-114091 Japanese Patent Laid-Open No. 11-149159 JP 2007-507610 A JP 2010-53177 A

  Accordingly, an object of the present invention is a water-based ink useful from the viewpoint of environmental protection and the like, and can be printed and printed by an ink jet printing method capable of fine and accurate printing, and ferric chloride at the time of etching. Another object of the present invention is to provide a water-based inkjet ink for an etching resist that can withstand a corrosive liquid that is an aqueous solution of an inorganic compound such as an aqueous solution and that can be dissolved and developed in an aqueous alkaline solution.

  As a result of diligent research to solve the above problems, the present inventors have found the properties of a polymer that can function effectively as a water-based ink for an etching resist, and achieved the present invention. That is, the present inventors use a vinyl polymer having a carboxyl group in its structure, which is an acid group that can be alkali-developed, and further use the polymer for at least one of the acid values of the polymer derived from the carboxyl group. It has been found that it is effective to neutralize the part with an alkali and mix it in the form of an aqueous dispersion or emulsion without dissolving it in the water constituting the ink and the water-soluble organic solvent (hereinafter also referred to as an aqueous medium). It was. By making the water-based ink containing the polymer constituted in this way, the water-based ink having a reduced viscosity can be obtained regardless of whether the polymer structure has many carboxyl groups or a large amount. By achieving the low viscosity of the ink, ink jet printing can be performed. As a result, fine line drawing can be accurately printed by ink jet printing. In addition to the suitability as an ink jet ink, the present inventors have found that the above-mentioned polymer characterizing the present invention is excellent in etching resistance and alkali developability, and the present invention is used as an aqueous ink jet ink composition for an etching resist. The invention has been completed.

That is, this invention provides the water-based inkjet ink composition for etching resists shown below.
[1] An etching resist ink printed by an ink jet printing method, comprising at least water, a water-soluble organic solvent, and a polymer, wherein the polymer is an addition of a monomer containing an α, β unsaturated bond It is obtained by polymerization and contains at least an α, β unsaturated bond-containing monomer having a carboxyl group as a constituent, its acid value is 50 to 250 mgKOH / g, and its number average molecular weight is 2,000 to 20,000. 0, further, the form of the polymer in the ink is, by neutralizing at least a portion of the acid value of the polymer, the average particle diameter becomes aqueous dispersion or emulsion of 10nm~200nm cage, polymers in the form of polymer after the neutralization neutralization for the water dispersion or emulsion, derived from the carboxyl group Of at least a portion of the acid value, ammonia; mono- or di- or trialkyl (1-4 carbon atoms) amine; monoalkanol (carbon atoms 2 or 3) an amine; mono- or dialkyl (1-4 carbon atoms) at least the polymer in one of compound selected from the group consisting of mono-alkanols (2 or 3 carbon atoms) amine are such that neutralize so as not to water-soluble, and the viscosity of the ink is 2 An aqueous ink-jet ink composition for etching resists, characterized in that it is 20 mPa · s .

[2] The ink composition according to the above [1], having a pH of 5 to 8.2 and a viscosity of 3 to 10 mPa · s at 25 ° C.
[3] The ink composition according to [1] or [2], wherein the weight average molecular weight / number average molecular weight, which is the molecular weight distribution of the polymer, is 1.6 or less.

[4] The polymer has an AB block copolymer structure, the polymer block of A has an acid value of 0 to 50 mgKOH / g and a number average molecular weight of 1,000 to 5,000, The ink composition according to any one of [1] to [3], wherein the polymer block has an acid value of 50 to 200 mg KOH / g and a number average molecular weight of 1,000 to 15,000.

In addition, in the ink composition according to any one of [1] to [4], it is preferable that the following are satisfied as ink components.
[5] An ink composition further comprising a dye or pigment as a colorant component.
[6] An ink composition further comprising an aqueous ultraviolet curable monomer and / or oligomer as a curing component.

  According to the present invention, a water-based ink that is useful from the viewpoint of environmental protection and the like, a polymer that can be printed and printed by an ink jet printing method capable of fine and accurate printing, and formed with the ink. The layer is resistant to a corrosive liquid that is an aqueous solution of an inorganic compound such as ferric chloride at the time of etching, and further, an aqueous inkjet ink composition useful for an etching resist that can be easily dissolved or peeled off with an alkaline developer. Provided. According to the present invention, by using this aqueous inkjet ink composition for an etching resist (hereinafter simply referred to as an ink composition or ink), for example, metal processing, electronic circuit, printed circuit board, plate making, semiconductor field, color filter In image formation and pattern formation in various fields such as, it is possible to easily form fine and accurate images, characters, circuits, patterns, and the like.

Next, the present invention will be described in more detail with reference to preferred embodiments for carrying out the present invention.
The ink composition of the present invention can function as a resist used when an etching pattern is formed on a material as described below. A material having a corrosive layer (a metal layer such as copper or zinc, or a resin layer) is inkjet-printed (including a drying step) with the aqueous ink of the present invention to form a polymer film having a fine line drawing. Next, the corrosive layer is removed with a corrosive aqueous solution such as an aqueous ferric chloride solution, but the corrosive layer portion provided with the polymer layer formed with the aqueous ink of the present invention is protected without being removed. Next, the carboxyl group of the polymer layer is neutralized and ionized with an aqueous alkaline solution, and the polymer film is removed as water-soluble. As a result, unnecessary portions are removed, and a fine line drawing of the corrosion layer is formed on the material. As a specific example, for example, if the corrosive layer is copper, it is possible to easily form a precise circuit or pattern.

Since the ink composition of the present invention is used for special applications as described above, it also requires required performance different from that of a normal inkjet ink composition. Become.
(1) A polymer film can be formed while being water-based for environmental conservation.
(2) It has a low viscosity (for example, 5 mPa · s) that can be ejected by an ink jet printing method, and dissolves again in a liquid medium even when dried by a head.
(3) A polymer film having high adhesion can be formed on a material having a corrosion layer such as a metal layer or a resin layer.
(4) The formed polymer film is a polymer film as a protective layer that can withstand a corrosive aqueous solution, and is insoluble in water.
(5) The formed polymer film is ionized, dissolved and removed by alkali development.

  In view of the above-mentioned required performance, the present inventors diligently studied requirements for making a polymer applicable to an aqueous inkjet ink composition for an etching resist. First, since it is necessary to finally be able to develop with an alkali, it is essential for the polymer to be a protective film to have many acid groups in its structure in order to make it a polymer that can be ionized with an alkali and dissolved in water. become. Alternatively, in order to achieve water solubility, a water-soluble group such as polyether that exhibits hydrophilicity may be introduced into the structure. However, in alkali development, the polymer having the acid group is dissolved in water, so if all the acid groups are neutralized to make an ink, the viscosity becomes high, and the low viscosity ink that can be printed by inkjet printing. do not become. In addition, if the structure has a hydrophilic group, it will dissolve in the corrosive aqueous solution, resulting in another problem that it cannot function as a strong protective film. From these facts, in order to satisfy the required performance of the ink of the present invention that is used for etching resist and for inkjet printing, the present inventors do not increase the viscosity of the ink and decompose it into a corrosive aqueous solution. It came to the conclusion that it is necessary to develop a polymer component that does not dissolve, and that has the property of dissolving in an alkaline developer and dissolving in water.

  As a result of intensive studies on the polymer component contained in the ink composition from the above viewpoint, the present inventors have found that the above-described problems can be solved by the following method, and have achieved the present invention. That is, in an aqueous ink comprising at least water, a water-soluble organic solvent, and a binder, the binder is a vinyl polymer having a carboxyl group, and a part of the carboxyl group is ionized by being neutralized with an alkali. All of the above problems can be solved by using an aqueous dispersion or emulsion of the polymer in a form dispersed and emulsified in an aqueous medium.

More specifically, the polymer needs to be an aqueous dispersion or emulsion having an average particle diameter of 10 nm to 200 nm that satisfies all of the following requirements.
(1) It was obtained by addition polymerization of a monomer containing an α, β unsaturated bond.
(2) An addition-polymerized monomer having an α, β-unsaturated bond-containing monomer having a carboxyl group and having an acid value in the polymer of 50 to 250 mgKOH / g.
(3) The number average molecular weight is 2,000 to 20,000.
(4) At least a part of the acid value of the carboxyl group content (at least a part of the acid value of the polymer derived from the carboxyl group) is neutralized with an alkali. Here, at least a part means that about 10 to 100 mgKOH / g of the acid value derived from the carboxyl group inherent in the polymer is neutralized, and a part of the acid value described above is This means that a partially neutralized ink is used as the ink component.
(5) Alkali for partial neutralization is ammonia; mono-, di- or trialkyl (1 to 4 carbon atoms) amine; monoalkanol (2 or 3 carbon atoms) amine; mono or dialkyl (1 to 4 carbon atoms) It is at least one selected from the group consisting of monoalkanol (carbon number 2 or 3) amine.

  Hereinafter, the constituent components of the polymer used in the present invention will be described in detail. The polymer is a vinyl polymer obtained by addition polymerization of an α, β unsaturated bond-containing monomer (hereinafter, also simply referred to as a vinyl monomer or a monomer). Specifically, any polymer species such as olefin, styrene, acrylic, vinyl ether, vinyl ester, vinyl amide, vinyl halide monomer, and the polymer species that can be used in combination of the monomers used And a vinyl monomer having a carboxyl group as a component is essential.

  Although it does not specifically limit as a vinyl-type monomer which has a carboxyl group used by this invention, The following are mentioned. For example, phthalic anhydride or succinic anhydride to a hydroxyl group-containing monomer such as vinyl benzoic acid, (meth) acrylic acid, itaconic acid, maleic acid, fumaric acid, acrylic acid dimer or (meth) acrylic acid monohydroxyalkyl ester A monomer obtained by reacting a dibasic acid such as α-chloroacrylic acid or the like can be used.

  The polymer characterizing the present invention is a homopolymer of a carboxyl group-containing monomer as mentioned above or a copolymer with another vinyl monomer. The other vinyl monomer that can be used in this case is not particularly limited as long as it is an α, β unsaturated bond-containing monomer capable of addition polymerization, and examples thereof include the following. For example, unsaturated hydrocarbon monomers such as ethylene and propylene; aromatic hydrocarbon monomers such as styrene and vinyl toluene; halogen vinyl monomers such as chloroethylene and tetrafluoroethylene; nitrile monomers such as (meth) acrylonitrile A monomer of (meth) acrylate ester such as methyl (meth) acrylate and cyclohexyl (meth) acrylate; an amide vinyl monomer such as (meth) acrylamide and N, N-dimethyl (meth) acrylamide; Vinyl ester monomers such as vinyl acetate and vinyl propionate; vinyl ether monomers such as vinyl t-butyl ether; vinylamide monomers such as N-vinylcaprolactam can be used.

  In particular, in the present invention, it is preferable to use a polymer comprising an aromatic hydrocarbon monomer or a (meth) acrylic acid ester monomer as the other monomer. The reason is that these monomers can be easily improved in performance and performance optimization due to the variety of monomers, and can be made into a polymer structure whose structure is easily controlled industrially by living radical polymerization. is there.

  Furthermore, examples of the aromatic hydrocarbon monomer that can be suitably used for the synthesis of the polymer characterizing the present invention include the following. For example, those selected from styrene, vinyl toluene, α-methyl styrene, hydroxy styrene, t-butyl vinyl benzene ether, chloromethyl styrene, ethyl styrene, vinyl naphthalene, vinyl biphenyl, vinyl anthracene, styrene sulfonic acid, etc. Can be used.

  In addition, examples of the (meth) acrylic acid ester monomer that can be suitably used for the synthesis of the polymer characterizing the present invention include the following conventionally known various monomers, and any of them can be used. Examples of the monomer include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, 2-methylpropane (meth) acrylate, t-butyl ( (Meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, lauryl ( (Meth) acrylate, tetradecyl (meth) acrylate, octadecyl (meth) acrylate, behenyl (meth) acrylate, isostearyl (meth) acrylate, cyclohexyl (meth) acrylate, -Butylcyclohexyl (meth) acrylate, isobornyl (meth) acrylate, trimethylcyclohexyl (meth) acrylate, cyclodecyl (meth) acrylate, cyclodecylmethyl (meth) acrylate, tricyclodecyl (meth) acrylate, benzyl (meth) acrylate, phenyl Alkyl such as (meth) acrylate, naphthyl (meth) acrylate, allyl (meth) acrylate, cycloalkyl (meth) acrylate;

  2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, cyclohexanedimethanol mono (meth) acrylate, cyclohexanediol mono (meta) ) Hydroxyl-containing (meth) acrylates such as acrylates;

  Mono (meth) acrylates of polyalkylene glycols such as poly (n = 2 or more) ethylene glycol mono (meth) acrylate, poly (n = 2 or more) propylene glycol mono (meth) acrylate;

  (Poly) ethylene glycol monomethyl ether (meth) acrylate, (poly) ethylene glycol monolauryl ether (meth) acrylate (glycol ether (meth) acrylates such as (poly) propylene glycol monomethyl ether (meth) acrylate);

  Glycidyl group-containing (meth) acrylates such as glycidyl (meth) acrylate, 3,4-epoxycyclohexyl (meth) acrylate, (meth) acryloyloxyethyl glycidyl ether, (meth) acryloyloxyethoxyethyl glycidyl ether;

  Contains isocyanate groups such as (meth) acryloyloxyethyl isocyanate, 2- (2-isocyanatoethoxy) ethyl (meth) acrylate, and monomers that are blocked with ε-caprolactone, MEK oxime, pyrazole, etc. (Meth) acrylate;

  Cyclic (meth) acrylates such as tetrahydrofurfuryl (meth) acrylate and oxetanylmethyl (meth) acrylate;

  Amino group-containing (meth) acrylates such as dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, t-butylaminoethyl (meth) acrylate;

  Halogen element-containing (meth) acrylates such as octafluorooctyl (meth) acrylate and tetrafluoroethyl (meth) acrylate;

  Absorbs ultraviolet light such as 2- (4-benzoxy-3-hydroxyphenoxy) ethyl (meth) acrylate, 2- (2′-hydroxy-5- (meth) acryloyloxyethylphenyl) -2H-benzotriazole (meta ) Acrylate;

  And monomers such as a silicon atom-containing (meth) acrylate having a trimethoxysilyl group or a dimethylsilicone chain.

  Moreover, the macromonomer etc. which are obtained by introduce | transducing a (meth) acryl group into the one terminal of the oligomer obtained by superposing | polymerizing these monomers can also be used.

  Moreover, as a monomer structural component used above, it is not limited to the above, The following can be used. For example, an acrylic resin synthesized using a (meth) acrylate monomer having a functional group such as a hydroxyl group or a carboxyl group as described above, and a (meth) acrylate having a group capable of reacting with these functional groups, for example, isocyanate It may be one in which a photosensitive group is introduced by reacting ethyl (meth) acrylate, glycidyl (meth) acrylate, or the like.

  Moreover, the monomer which has the sulfonic acid group and phosphoric acid group which are acids other than a carboxyl group which are listed below can also be used. Specific examples include styrene sulfonic acid, vinyl sulfonic acid, acrylamide-2-methylpropane sulfonic acid, and ethyl phosphate (meth) acrylate.

  The polymer characterizing the present invention is composed of one or more of the above-listed monomers as constituents, but the acid value in the polymer is 50 to 250 mg KOH so that the protective film formed by the polymer can be alkali-developed. / G. That is, if it is less than 50 mgKOH / g, sufficient alkali development cannot be performed, or dissolution becomes very slow, which is not practical. On the other hand, if the acid value in the polymer is larger than 250 mgKOH / g, there are too many acid groups, resulting in water solubility, which may be dissolved in a corrosive aqueous solution at the time of etching. Is bad. More preferably, the polymer having an acid value of 65 to 150 mgKOH / g is preferably used. With an appropriate acid value of the polymer, the polymer film formed by the ink of the present invention can achieve sufficient alkali developability.

  In the present invention, a polymer having the above acid value is used as a constituent component of the ink. However, if all of these acid groups are neutralized, the polymer dissolves in water and increases in viscosity when converted into an ink. There is a fear that stable ejection cannot be performed by inkjet printing. Therefore, in the present invention, water solubility is eliminated by neutralizing at least a part of the acid value of the polymer derived from the carboxyl group in the structure, and the polymer is dispersed in water with a specific average particle size. Or an emulsion. By comprising in this way, when the said polymer is contained in an ink, it can be set as a low viscosity ink. For this reason, the ink of the present invention can be inkjet-printed in a stable state. In addition, since it is a low-viscosity aqueous dispersion or emulsion, a large amount of polymer component can be blended in the ink, and as a result, a resist film that functions well can be formed.

  Regarding the neutralization of a part of the polymer described above, it is adjusted in a range where water is insoluble, specifically, a range in which the polymer becomes an aqueous dispersion or emulsion having an average particle size of 10 nm to 200 nm. How much acid value should be neutralized out of 50 to 250 mgKOH / g which is the range of acid value of the polymer used in the present invention and 65 to 150 mgKOH / g which is a more preferable range (hereinafter referred to as neutralization rate) Since the properties of the polymer change depending on the properties of the monomer to be polymerized, it cannot be generally said. However, in order to obtain an aqueous dispersion or emulsion having an average particle size of 10 nm to 200 nm, it is preferable to neutralize 10 to 100 mg KOH / g of the acid value of the polymer derived from the carboxyl group in the polymer. For example, in an extreme example, in the case of 50 mg KOH / g, which is the minimum value in the range of the acid value, even if all 50 mg KOH / g is neutralized, it does not have to be water-soluble. Preferably, however, it is neutralized at less than 50 mg KOH / g. In the case of 250 mgKOH / g, which is the maximum value in the range of the acid value, neutralization is preferably performed in the range of 100 mgKOH / g or less. This neutralization rate is appropriately determined depending on the monomer used because the properties of the polymer obtained vary depending on the monomer used for the polymerization.

  Next, the polymer used in the present invention has a number average molecular weight of 2,000 to 20,000. The number average molecular weight is a polystyrene-reduced number average molecular weight (Mn) of gel permeation chromatography (hereinafter abbreviated as GPC). In addition, all the following molecular weights are the values of polystyrene conversion by GPC measurement. If the number average molecular weight is less than 2,000, the physical properties of the polymer are weak, and the polymer film (protective film) formed by the ink of the present invention becomes brittle or liquid. The performance as a protective film may be inferior, such as dissolution. On the other hand, when the number average molecular weight is larger than 20,000, the final alkali development may not be dissolved even if there is a certain acid value, or it may take a long time to develop. Furthermore, it is preferable to use a polymer having a number average molecular weight in the range of 5,000 to 17,000.

  In the monomer composition as described above, it has an acid value specified in the present invention, and further neutralizes a part of the acid value to form an aqueous dispersion or emulsion. In this case, the average particle size of the polymer is 10 to 10%. 200 nm. The average particle diameter may be any measurement method value, for example, a dynamic light scattering method. Hereinafter, it is set as the average particle diameter measured by the light scattering method. If the average particle size of the polymer in the ink is less than 10 nm, viscosity may be obtained even in a dispersion. On the other hand, when the average particle diameter of the polymer is larger than 200 nm, the polymer may be clogged in the ink jet head of the ink jet printing apparatus, or the dots may become large and a fine line image may not be drawn when printing is performed. A more preferable average particle diameter of the polymer is 20 nm to 120 nm.

  The above polymer can be obtained by a conventionally known polymerization method and is not particularly limited. A radical polymerization using a normal azo radical generator or a peroxide radical generator can be used, and a new polymerization method can be obtained by a living radical polymerization method.

Living radical polymerization has various methods and is not particularly limited. Living radical polymerization may be performed according to a conventionally known method as exemplified below. As an example of living radical polymerization, the following method is mentioned, for example.
(A) a polymerization method using nitroxide (Nitroxide polymerized polymerization (NMP method)),
(B) an atom transfer radical polymerization method (ATRP method) in which a protective group that is a halogen element is extracted with a metal complex or the like;
(C) Reversible Addition Fragmentation Transfer Polymerization (RAFT method) using dithioester or xanthate compound,
(D) a method using an organic tellurium compound or an organic bismuth compound,
(E) a method using a cobalt complex,
(F) iodine transfer polymerization method,
(G) Reversible Transfer Catalyzed Polymerization (RTCP method) using iodine as a protecting group and using a compound containing phosphorus, nitrogen, oxygen, or hydrocarbon as a catalyst.

  In addition, the polymer constituting the ink of the present invention can be used with any value of molecular weight distribution which is weight average molecular weight / number average molecular weight obtained by polymerization. Especially, since the molecular weight distribution can be narrowed in living radical polymerization, it is preferable to use a polymer obtained by living radical polymerization. The molecular weight of the polymer is narrow, that is, this means that the molecular weight is uniform. In this case, since the molecular weight of each polymer chain is the same, the solubility becomes nearly uniform. As a result, a sharp line drawing edge can be formed when alkali development is performed. It is preferable to use a polymer having a molecular weight distribution of 1.6 or less, more preferably 1.5 or less.

  As described above, the polymer characterizing the present invention may be a polymer obtained by polymerization using a polymerization method such as radical polymerization or living radical polymerization, and the structure thereof is random structure, block structure, A structure such as a graft structure or a star polymer structure can be employed, and any structure can be used. In the present invention, more preferably, the structure of the polymer is an AB block copolymer, and the polymer block of A has an acid value of 0 to 50 mgKOH / g and a number average molecular weight of 1,000 to 5, It is preferable that the polymer block of B has an acid value of 50 to 200 mgKOH / g and a number average molecular weight of 1,000 to 15,000.

  In the present invention, the present inventors consider the reason why the AB block copolymer having the above structure is particularly suitable as follows. A polymer block of A that is insoluble or difficult to dissolve in water forms particles because it has the above structure, while the polymer block of B dissolves in water by neutralization to form a dispersion or emulsion to lower the viscosity, and A Since the polymer block is insoluble in water, it is more insoluble in the corrosive aqueous solution, and the adhesion of the substrate can be further improved. As a result, the use of the polymer makes a better ink for etching resist. According to the study by the present inventors, more preferably, an AB block copolymer in which the acid value of the polymer block of A is 0 to 20 mgKOH / g and the acid value of the polymer block of B is 60 to 150 mgKOH / g is used. Use it.

  The number average molecular weight of the A polymer block of the AB block copolymer suitable for the present invention is 1,000 to 5,000, but this range is hydrophobic and improves adhesion, and at the time of alkali development. It is in a range that does not affect such as difficult to dissolve. More preferably, a polymer having a polymer block of A having a number average molecular weight of 2,000 to 5,000 may be used. The number average molecular weight of the polymer block B of the AB block copolymer suitable for the present invention is 1,000 to 15,000, and this is a range in which water solubility capable of alkali development can be exhibited. When the number average molecular weight is less than 1,000, alkali development may not be possible. On the other hand, when the number average molecular weight exceeds 15,000, the number average molecular weight of the polymer block of B is too large, and development takes too much time. is not. More preferably, an AB block copolymer in which the number average molecular weight of the polymer block of B is 4,000 to 7,000 may be used.

  As the monomer used for the synthesis of the AB block copolymer described above, the monomer can be used, and is not particularly limited. Further, by using the above-described living radical polymerization, it is possible to easily synthesize an AB block copolymer in which each of the A polymer block and the B polymer block is suitable as described above. The method is not particularly limited.

  The method for producing an aqueous dispersion or emulsion of a specific polymer constituting the ink of the present invention is not particularly limited. For example, it can be obtained by adding an aqueous solution in which an alkali that neutralizes the acid value is dissolved after solution polymerization, or by precipitating the polymer obtained by solution polymerization with a poor solvent or drying the polymer. It can also be obtained by neutralizing with an aqueous alkali solution. Alternatively, it may be obtained by emulsion polymerization in the presence of an emulsifier or a protective colloidal water-soluble polymer and then neutralizing with an alkali. As described above, neutralization in the above means that the acid value of the polymer used in the present invention is partially neutralized.

  Next, the alkali used for partially neutralizing the acid value of the polymer used in the present invention will be described. The alkali is preferably a volatile amine in consideration of the case where there is a drying step after ink jet printing. Specifically, ammonia, mono- or di- or trialkyl (1 to 4 carbon atoms) amine, monoalkanol (carbon number) 2 or 3) It is necessary to use an amine, mono or dialkyl (C1 to C4) monoalkanol (C2 or C3) amine. More specifically, ammonia; mono- or di- or trialkyl (1 to 4 carbon atoms) amine such as methylamine, dimethylamine, trimethylamine, ethylamine, triethylamine, propylamine, butylamine; monoethanolamine, monopropanolamine, etc. Any one or more of mono- or dialkyl (C1-C4) monoalkanolamines such as monoalkanolamine and dimethylaminoethanol are preferable. More preferably, ammonia, trimethylamine, or monoethanolamine is preferable because it has high volatility, hardly remains, and is easily available as a commercial product.

  The ink composition of the present invention comprises at least the specific polymer described above, which is a material for forming a protective film, water, and a water-soluble solvent. The action of the water-soluble solvent in the ink is to prevent the head of the inkjet ink from drying and to improve the wettability of the ink to the substrate, as described below. That is, when the ink is dried, the head is clogged or the ink ejection is unstable. On the other hand, when a water-soluble solvent is used, the head can be prevented from drying. Preferably, a water-soluble solvent having a boiling point of 100 ° C. or higher is used. Further, when only water and a polymer are used, the surface tension is high and it may be difficult to wet the substrate. However, by adding a water-soluble solvent, the surface tension can be lowered to advantageously form a film. In particular, although there is no limitation on the surface tension of the ink, it is considered that the surface tension is preferably 50 mN / m or less in the present invention.

  The water-soluble solvent used in the present invention is not particularly limited. A solvent that completely dissolves in water or a solvent that dissolves in water as much as possible may be used, but a solvent having a solubility of 20 g / liter or more of water is preferably used. Examples of water-soluble solvents that can be used in the present invention include alcohol solvents such as methanol, propanol, and butanol; ethylene glycol, propylene glycol, 1,3-butylene glycol, 1,4-butanediol, 1,2-hexanediol. Polyhydric alcohol solvents such as ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, diethylene glycol dimethyl ether, diethylene glycol monoethyl ether acetate, 3-methoxy-1-butanol, 3-methoxy-3-methyl-butanol, propylene glycol Glycol solvents such as monomethyl ether, propylene glycol monopropyl ether, 3-methoxy-3-methylbutyl acetate; milk Ethyl, ester solvents such as ε- caprolactone; dimethylacetamide, N- methylpyrrolidone, amide solvents such as pyrrolidone; dimethyl sulfoxide, polar solvents such as tetramethyl urea. One or more of these are selected and used.

  The amount of the water, water-soluble solvent and polymer constituting the ink of the present invention is adjusted depending on the type of ink jet printer using the ink and the printing conditions, and the blending ratio is not particularly limited. Preferably, they are 30-70 mass% of water, 5-40 mass% of water-soluble solvents, and 5-30 mass% of polymer components. Since the feature of the present invention is a polymer component having a reduced viscosity which is an aqueous dispersion or emulsion, the polymer component can be increased. Since the ink of the present invention is a special purpose ink for etching resist, a certain amount of protective film thickness is required to form a pattern that retains the performance as a protective film with the ink. In other words, the ink of the present invention should have a large amount of component of the ink to be ejected. For this reason, the polymer component in the ink is preferably 10 to 20% by mass.

  The ink composition of the present invention has the above-described configuration and is useful as an etching resist. As described below, by adopting the above-described configuration, the properties of the ink are pH at 25 ° C. Is in the range of 5 to 8.2, and the viscosity is in the range of 2 to 20 mPa · s.

  First, the pH of the ink in the ink of the present invention is such that the contained polymer is partially neutralized with carboxyl groups, so that unneutralized carboxyl groups are present, and the pH is acidic to weakly alkaline. It becomes. In this range, the pH is 5 to 8.2, and in this range, an aqueous dispersion or emulsion is obtained. When the pH is less than 5, the stability of the aqueous dispersion or emulsion is deteriorated, and precipitation or sedimentation may occur. On the other hand, if the pH is 8.2 or higher, the solution is in a dissolved state, which may increase the viscosity. A more preferable pH of the ink is 5.5-8.

  The required viscosity of the ink varies depending on the performance of the ink jet printer to which the ink is applied, but is preferably 2 to 20 mPa · s. If it is less than 2 mPa · s, the ejection stability tends to be poor, and if it is greater than 20 mPa · s, there is a possibility that it may become impossible to eject. A more preferable viscosity of the ink is 3 to 10 mPa · s.

  The above is the basic aqueous inkjet ink composition for an etching resist of the present invention, but a dye or a pigment may be used as a coloring component as necessary. It is because it can be used for the visibility of the printed part. The dye or pigment is not particularly limited. The dye is preferably a water-soluble dye, and it is necessary to use at least a pigment dispersion in which the pigment is dispersed in water. The pigment can be either an inorganic pigment or an organic pigment. Examples include organic dyes and pigments such as azo, phthalocyanine, quinacridone, anthraquinone, diketopyrrolopyrrole, perylene, quinophthalone, and dioxazine, carbon black, titanium oxide, and other inorganic pigments. Can be mentioned.

  The blending amount of the colorant in the ink of the present invention is also arbitrary. If it is desired to clearly see the image, the blending amount is increased, and if it is desired to reduce the thickness, the blending amount may be decreased. The blending amount is preferably 0.1 to 3% by mass in the case of a dye and 0.5 to 5% by mass in the case of a pigment.

  In addition, an aqueous ultraviolet curable monomer and / or oligomer may be added to the ink as the curable component. As these components, conventionally known ones can be used, and there is no particular limitation. Examples of the ultraviolet curable monomer include the aforementioned (meth) acrylate monomers, and examples of the oligomer include glycol-based polyvalent acrylates such as polyethylene glycol di (meth) acrylate. By adding a curable component, the protective film formed of the ink can have a cross-linked structure, so that the resistance to the corrosive liquid can be further improved, and the performance improvement effect as a protective film can be obtained.

  Furthermore, additives such as a polymerization initiator, a photoacid generator, a surfactant, an antiseptic, a leveling agent, and an antifoaming agent can be blended as needed, but are not particularly limited.

  The etching method to which the ink composition of the present invention is applied is not particularly limited, such as the material used, the corrosive solution, the alkaline developer, the method and conditions thereof, and conventionally known materials and methods are used. It is done. That is, it is not limited at all as long as printing is performed with the aqueous inkjet ink composition of the present invention capable of inkjet printing, a protective film is formed on the material, and then an etching step and an alkali development step are included. Examples of the material for forming the protective film include metal steel plates such as aluminum, brass, and stainless steel, copper-clad laminates, aluminum-deposited silicon substrates, and copper foil-laminated polyimide resin films.

  As etching solution used for etching, ferric chloride aqueous solution, cupric chloride aqueous solution, ammonia copper aqueous solution, high concentration sodium hydroxide aqueous solution, high concentration hydrochloric acid, hydrogen fluoride water, ferric nitrate aqueous solution, etc. can be used. As the alkaline developer, an aqueous potassium hydroxide solution, an aqueous tetramethylammonium hydroxide solution, an aqueous solution of sodium (meth) silicate, and the like can be used, but their concentrations are arbitrary.

  As ink jet printing performed in the step of forming a protective film on a material using the ink composition of the present invention as an etching resist, a conventionally known ink jet method is used, and printing with a piezo head or a thermal head can also be used. Since the ink of the present invention is aqueous, it is preferable to include a drying step after printing. Specifically, after printing, it is preferable to form a protective film by drying at a drying temperature of 50 to 130 ° C. for several seconds to 30 minutes. At this time, all or part of water, alkali, and organic solvent, which are constituents of the ink, are volatilized to form a polymer film that is a protective layer. Next, etching is performed with a corrosive liquid, and the temperature is arbitrary during that time, and the material of the portion not protected by the polymer layer is corroded and dissolved. Then, preferably after washing, the polymer layer is dissolved by immersing in an alkali developer. The development time and temperature are arbitrary. Through these series of steps, fine and accurate line drawings such as characters, images, patterns, and circuits can be obtained.

  Next, the present invention will be described in more detail with specific examples. Hereinafter, “part” and “%” in the text are based on mass unless otherwise specified.

[Synthesis Example 1] Random polymer type A reaction vessel equipped with a stirrer, a reverse flow condenser, and a thermometer was charged with 200 parts of butyl cellosolve (hereinafter abbreviated as BCS) and 200 parts of butyl diglycol (hereinafter abbreviated as BDG) at 85 ° C. Heated. When the temperature reached 85 ° C., 4 parts of azobisisobutyronitrile (hereinafter abbreviated as AIBN) was added. Separately prepared 80 parts of styrene monomer (hereinafter abbreviated as St), 80 parts of butyl acrylate (hereinafter abbreviated as BA), 80 parts of methyl methacrylate (hereinafter abbreviated as MMA), 40 parts of lauryl methacrylate (hereinafter abbreviated as LMA), hydroxy 138 parts were added among 416 parts of monomer solutions which mixed 60 parts of ethyl methacrylate (henceforth HEMA), 60 parts of methacrylic acid, and 16 parts of AIBN. The remaining 278 parts were added slowly dropwise over 1 hour 30 minutes. After completion of the dropwise addition of the monomer solution, 2 parts of AIBN was added, and the mixture was further stirred for 5 hours 30 minutes at 85 ° C. to obtain a polymer solution P-01.

  When the polymer solution P-01 was sampled and the solid content was measured, it was 50.3%, and the polymerization conversion rate converted from the nonvolatile content was almost 100% (hereinafter, the polymerization conversion rate and the polymerization rate were measured by this method). ) The number average molecular weight (hereinafter abbreviated as Mn) in a differential refractometer (hereinafter abbreviated as RI) of the gel permeation chromatography (hereinafter abbreviated as GPC) was 9,400, and the weight average molecular weight (hereinafter abbreviated as Mw). Was 18,500, and the dispersity obtained from Mw / Mn (hereinafter abbreviated as PDI) was 1.97. The acid value was determined to be 97.7 mgKOH / g when titrated with toluene / ethanol = 50/50 solution using phenolphthalein as the indicator and 0.1 NKOH ethanol solution as the titrant.

[Neutralization Example 1]
In a beaker, 100 parts of the polymer solution P-01 was added, 4.7 parts of 28% ammonia water and 15.3 parts of water were added, and the mixture was neutralized by stirring. Subsequently, 40 parts of water was added and stirred. Furthermore, 40 parts of water was added and stirred to obtain a polymer solution P-01A. At this time, the neutralization rate with respect to the acid group of P-01A was 60%, and 58.6 mgKOH / g of 97.7 mgKOH / g of the polymer acid value was partially neutralized (hereinafter, partial neutralization was neutralized). Expressed as a rate). The solid content was 25.3%. Further, a translucent aqueous dispersion having a pH of 7.9 (measured at 25 ° C., hereinafter 25 ° C.) obtained by diluting P-01A 10 times with water is obtained, diluted with water, and particles by light scattering. The diameter was measured (in principle, the volume-based average particle diameter. Hereinafter, the average particle diameter was measured by this method). As a result, the average particle size was 35 nm.

[Comparative neutralization example 1]
In the same manner as in Neutralization Example 1, polymer solution P-01 was charged, and 8.7 parts of 28% aqueous ammonia and 11.3 parts of water were added and neutralized by stirring. Subsequently, 40 parts of water was added and stirred. Furthermore, 40 parts of water was added and stirred to obtain a polymer solution P-01B. At this time, the neutralization rate of the polymer solution was 110% to neutralize all acid groups, and the solid content was 25.4%. Further, the polymer solution became a highly viscous transparent liquid. The pH was 9.2. Since it was transparent, the average particle size could not be measured.

[Neutralization Example 2]
In the same manner as in Neutralization Example 1, the polymer solution P-01 was charged, and 2.1 parts of monoethanolamine and 17.9 parts of water were added and neutralized by stirring. Subsequently, 40 parts of water was added and stirred. Furthermore, 40 parts of water was added and stirred to obtain a polymer solution P-01C. At this time, the neutralization rate of P-01C was 40%, and the solid content was 26.1%. The pH of a solution obtained by diluting P-01C 10 times with water was 8.0. A translucent aqueous dispersion was obtained. The average particle size was 41 nm.

[Comparative neutralization example 2]
The polymer solution P-01 was charged in the same manner as in Neutralization Example 1, 3.7 parts of diethanolamine and 16.3 parts of water were added, and the mixture was neutralized by stirring. Subsequently, 40 parts of water was added and stirred. Furthermore, 40 parts of water was added and stirred to obtain a polymer solution P-01D. At this time, the neutralization rate of P-01D was 40%, and the solid content was 26.3%. Moreover, the pH of the solution which diluted P-01D 10 times with water was 7.9. It was a translucent aqueous dispersion. The average particle size was 32 nm.

[Comparative neutralization example 3]
In the same manner as in Neutralization Example 1, polymer solution P-01 was charged, 5.2 parts of triethanolamine and 14.8 parts of water were added, and the mixture was neutralized by stirring. Subsequently, 40 parts of water was added and stirred. Furthermore, 40 parts of water was added and stirred to obtain a polymer solution P-01E. At this time, the neutralization rate of P-01E was 40%, and the solid content was 26.0%. The pH of a solution obtained by diluting P-01E 10 times with water was 7.7. It was a highly transparent liquid. The average particle size was 23 nm.

[Neutralization Example 3]
In the same manner as in Neutralization Example 1, polymer solution P-01 was charged, and 3.1 parts of dimethylaminoethanol and 16.9 parts of water were added and neutralized by stirring. Subsequently, 40 parts of water was added and stirred. Furthermore, 40 parts of water was added and stirred to obtain a polymer solution P-01F. At this time, the neutralization rate of P-01F was 40%, and the solid content was 26.2%. The pH of a solution obtained by diluting P-01F 10 times with water was 7.9. It was a translucent aqueous dispersion. The average particle size was 45 nm.

[Neutralization Example 4]
In the same manner as in Neutralization Example 1, the polymer solution P-01 was charged, and 4.7 parts of dimethylaminoethanol and 15.3 parts of water were added and neutralized by stirring. Subsequently, 40 parts of water was added and stirred. Furthermore, 40 parts of water was added and stirred to obtain a polymer solution P-01G. At this time, the neutralization rate of P-01G was 60%, and the solid content was 25.8%. The pH of a solution obtained by diluting P-01G 10 times with water was 8.2. The water dispersion was somewhat transparent. The average particle size was 36 nm.

[Comparative neutralization example 5]
In the same manner as in Neutralization Example 1, polymer solution P-01 was charged, and a mixed solution of 3.1 parts of sodium hydroxide and 16.9 parts of water was added, followed by stirring to neutralize. Subsequently, 40 parts of water was added and stirred. Furthermore, 40 parts of water was added and stirred to obtain a polymer solution P-01H. At this time, the neutralization degree of P-01H was 40%, and the solid content was 27.3%. The pH was 8.4. It was a highly transparent liquid. The particle size could not be detected. By being sodium hydroxide, the solubility in water is high, and it is considered that the particles were not clearly detected and could not be detected.

The above neutralization examples are summarized and shown in Table 1.

[Comparative Synthesis Example 1] Random polymer type having a hydrophilic chain 100 parts of ethanol and 100 parts of BDG were charged in a reaction vessel equipped with a stirrer, a reverse flow condenser and a thermometer, and heated to 75 ° C. When the temperature reached 75 ° C., separately prepared St 40 parts, MMA 30 parts, ethyl methacrylate (hereinafter abbreviated as EMA) 30 parts, lauryl methacrylate (hereinafter abbreviated as LMA) 40 parts, methacrylic acid 30 parts, molecular weight about 400 methoxypolyethylene glycol mono Of 205 parts of the monomer solution mixed with 30 parts of methacrylate (hereinafter abbreviated as PME-400) and 5 parts of 2,2′-azobis (2,4-dimethylvaleronitrile) (hereinafter abbreviated as V-65), 68 parts added. The remaining 137 parts were added dropwise over 1 hour 30 minutes. One hour after the completion of the monomer addition, 1 part of V-65 was added. After 1 hour, 1 part of V-65 was added. The mixture was further stirred at 75 ° C. for 3 hours to obtain a polymer solution P-02. The obtained P-02 was sampled, and the polymerization conversion rate converted was 100%. At this time, Mn of RI of GPC was 13,100, and PDI was 1.77. The acid value of the polymer was 97.8 mgKOH / g.

[Comparative neutralization example 5]
In a 500 ml beaker, 100 parts of polymer solution P-02 was charged, 2.1 parts of monoethanolamine and 17.9 parts of water were added, and the mixture was neutralized by stirring. Subsequently, 40 parts of water was added and stirred. Furthermore, 40 parts of water was added and stirred to obtain a polymer solution P-02A. At this time, the neutralization rate of P-02A was 40%, and the solid content was 26.4%. The pH of a solution obtained by diluting P-02A 10 times with water was 8.02 (25 ° C.). It was a liquid with a strong transparency, and the particle size could not be detected. This is probably because many polyethylene glycol chains are bonded in the structure of the polymer, so that the particles are not highly water-soluble (hydrophilic) and cannot be detected.

[Synthesis Example 2] Random Polymer Type with Narrow Molecular Weight Distribution (Low PDI) Using the same apparatus as in Synthesis Example 1, 172.9 parts of BDG, 70.4 parts of benzyl methacrylate (hereinafter abbreviated as BzMA), 8 .6 parts, HEMA 13.0 parts, iodine 1.0 part, 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile) (hereinafter abbreviated as V-70) 3.7 parts, N-eye Odosuccinimide (0.11 part) was charged, and the mixture was stirred at 40 ° C. with nitrogen flowing for polymerization for 8 hours to obtain a polymer solution P-03. Sampling and measurement of the solid content were 35.6% and the polymerization conversion was almost 100%. Mn by GPC was 10,900, Mw was 13,950, and PDI was 1.28. The acid value of the resin was 61.0 mgKOH / g by measuring the acid value. In addition, this synthetic method has taken the method of (g) described as an example of living radical polymerization in the text.

[Neutralization Example 5]
Into a 500 ml beaker, 142.8 parts of P-03 was charged, and 1.2 parts of monoethanolamine and 7.8 parts of water were added, and the mixture was neutralized by stirring. Subsequently, 20.0 parts of water was added and stirred. Furthermore, 27.2 parts of water was added and stirred to obtain a polymer solution P-03A. At this time, the neutralization rate of P-03A was 50%, and the solid content was 26.0%. The pH of a solution obtained by diluting P-03A 10 times with water was 7.9. A transparent white emulsion was obtained, and the average particle size was 62 nm.

[Synthesis Example 3] Block Polymer Type Using the same apparatus as in Synthesis Example 1, 179 parts of dimethyldiglycol, 35.2 parts of BzMA, 1.8 parts of methacrylic acid, 1.0 part of iodine, and V-70 are 5. 0 parts and 0.3 parts of diphenylmethane were charged and polymerized for 7 hours while flowing nitrogen to obtain a polymer block of A. A part was sampled, and the polymerization rate was almost 100%. Moreover, Mn was 4,300 and PDI was 1.12. As a result of measuring the acid value, it was 31.7 mgKOH / g. When a part of the polymer was neutralized with aqueous ammonia, it was precipitated without dissolving. It is thought that it did not dissolve because of its low acid value.

  Next, 52.8 parts of BzMA, 8.6 parts of methacrylic acid, and 6.5 parts of HEMA were charged and polymerized for another 4 hours to obtain P-04 as an AB block polymer. The polymerization rate was almost 100%, Mn was 16,800, and PDI was 1.36. That is, the molecular weight of the polymer block of B is 12,500. In this AB block polymer, it was confirmed that the polymer block of A was shifted to the high molecular weight side from the GPC peak. It is considered that this started from the polymer block of A and became an AB block polymer. Moreover, this polymer was 71.0 mgKOH / g as a result of an acid value measurement. If only the polymer block of B is seen, the acid value is 82.6 mgKOH / g from the calculation on the blending. The solid content was 51.0%. In addition, this synthetic method has taken the method of (g) described as an example of living radical polymerization in the text.

[Neutralization Example 6]
100 parts of P-04 was charged into a beaker, 2.3 parts of monoethanolamine and 17.7 parts of water were added, and the mixture was neutralized by stirring. Subsequently, 40 parts of water was added and stirred. Furthermore, 40 parts of water was added and stirred to obtain a polymer solution P-04A. At this time, the neutralization rate of P-04A was 60%, and the solid content was 25.6%. The pH of a solution obtained by diluting P-04A 10 times with water was 7.7. A transparent white emulsion was obtained, and the average particle size was 70 nm.

[Example 1]
In a 300 liter beaker, 59.3 parts of P-01A obtained in Neutralization Example 1, 0.3 part of Direct Blue 86, 20 parts of ethylene glycol, 2 parts of glycerin, and 18.4 parts of ion-exchanged water were blended. The mixture was stirred with a stirrer so as to be uniform. Subsequently, it filtered with the filter of 5 micrometers and then 1.2 micrometers, and created the ink. When the viscosity was measured, it was 3.6 mPa · s, and the pH was 7.5.

[Examples 2 to 4, Comparative Examples 1 to 5]
In the same manner as in Example 1, using P-01B to H and P-02A shown in Table 1, the amount of ion-exchanged water was adjusted so that the polymer content was 12% to prepare an ink. The main compositions and properties of these inks are shown in Table 2 together with the ink of Example 1.

[Evaluation Example 1]
10 points, 16 points, 24 points, and 40 points on a brass steel plate in which these inks are loaded into a cartridge bottle and surface oils and fats are removed with acetone using a piezo-type ink jet printer (manufactured by Mastermind, MMP813P). The character “Ei” was printed in the Mincho style with the font size of 、, and the printed matter was dried at 80 ° C. for 3 minutes to form a polymer film as a protective layer.

  As a result, when the ink compositions of Examples 1 to 4 were used, the ejection performance was good and the fine portions of “Splash” and “Harai”, which are the portions of the “elong” character of the print, were beautiful. It was confirmed that it was printed on. However, when the ink composition of Comparative Example 1 was used, printing could not be performed because ejection was impossible. This is thought to be because the viscosity of the ink was too high for this printing press, and an optimum low viscosity is considered necessary. Next, in the case where the ink compositions of Comparative Examples 2 and 3 were used, there was a slight disturbance in the above-mentioned portion of the “permanent” character. This is because the neutralized amine is difficult to volatilize and the amine has high hydrophilicity, and thus it is considered that disturbance occurred during drying. However, when the ink compositions of Comparative Examples 4 and 5 were used, the same results as in Examples 1 to 4 were obtained. This is probably because, in the ink compositions of Comparative Examples 4 and 5, particles were not observed in the polymer solution as a constituent component, but the polymer was successfully converted into particles in the ink composition solvent.

  The printed steel sheet was then immersed in a 20% aqueous ferric chloride solution at 30 ° C. for 8 minutes and etched. As a result, it was confirmed that there was no peeling of the polymer film when the inks of Examples 1 to 4 were used. This is presumably because the carboxyl group, which is an acid group in the structure of the polymer, increases the adhesion to the base material and is a polymer having an acid group, so it was not dissolved in a strong acid corrosive solution. On the other hand, when the inks of Comparative Examples 2 to 5 were used, it was confirmed that the polymer film was peeled off during the etching, and the performance as a resist was not maintained. This is because the neutralizing agent used for neutralizing the polymer as a component of the inks of Comparative Examples 2 to 4 was a high-boiling amine or metal salt, so that the carboxyl groups in the polymer structure remained neutralized and water This is considered to be because the solubility has come out and it has been dissolved in the corrosive liquid. Further, in the ink of Comparative Example 5, a lot of polyethylene glycol-based methacrylate is blended in the synthesis of the polymer in the component, and even if it is partially neutralized, the particles are not obvious and are highly hydrophilic. It is presumed that the polymer film formed with the ink was dissolved in the corrosive liquid and that the adhesion of the polymer film itself to the substrate was insufficient.

  Next, the etched aluminum steel plates in Examples 1 to 4 were thoroughly washed with ion-exchanged water and then immersed in a 2.5% aqueous potassium hydroxide solution for 15 seconds to perform a developing operation. As a result, in all of the examples, a part of the film was dropped out, but the polymer film was easily dissolved, and a beautiful “elong” character was variously formed on the brass steel plate. It was possible to form with the size of the font. It was confirmed that precise line drawings such as characters, images, patterns, and circuits can be drawn by using this technology.

[Example 5]
In the same apparatus as in Example 1, P-03 obtained in Synthesis Example 2 was partially neutralized, 46.1 parts of P-03A obtained in Neutralization Example 5, NAF color NAF5091 black (carbon black water) 8.7 parts of dispersion (35% pigment content, manufactured by Dainichi Seika Co., Ltd.), 7 parts of ethylene glycol, 7 parts of diethylene glycol and 31.2 parts of ion-exchanged water were mixed, and then 5 μm and then 1.2 μm The ink was prepared by filtering with a filter. The obtained black ink had a viscosity of 3.6 and a pH of 8.1.

[Evaluation Example 2]
In the same manner as in Evaluation Example 1, the black ink obtained in Example 5 was loaded into a cartridge bottle, and a 1 mm wire was applied to a copper foil laminated silicon wafer from which surface oils and fats were removed with acetone using the ink jet printer described above. Ten lines of width were printed with an interval of 1 mm. As a result, ejection was possible without any clogging of the head. Next, the printed material was dried at 100 ° C. for 1 minute to form a polymer layer. A beautiful line drawing could be obtained, and no peeling of the film was confirmed.

  Next, etching was performed in the same manner as in Evaluation Example 1. As a result, the copper foil disappeared, the silicon wafer was exposed, and a portion protected by the polymer layer remained. It was confirmed that the polymer layer had a performance as a resist without peeling off. Further, it was immersed in a 0.5% tetramethylammonium hydroxide aqueous solution for 5 seconds in the same manner. The polymer film was not peeled off as in the case of Evaluation Example 1, and it was confirmed that the polymer film was detached while being dissolved. This difference in the dissolution state is considered to be because the polymer P-03 used in this example has a low PDI. As a result, the above-described line drawing remained beautifully as a copper film. When the ink of this example is used, it is considered that a finer line drawing can be formed than when the inks of Examples 1 to 4 are used, and can be used for more delicate and precise patterning such as an electronic circuit diagram. it is conceivable that.

[Example 6]
In the same apparatus as in Example 1, P-04 obtained in Synthesis Example 3 was partially neutralized. 11.8 parts of P-04A obtained in Neutralization Example 6 and bisphenol A type poly (n + m = 6) After mixing 6 parts of ethylene glycol diacrylate, 10 parts of butyl cellosolve, 3 parts of glycerin, 68.4 parts of water, 0.3 part of benzophenone and 0.3 part of 1-hydroxycyclohexyl phenyl ketone, 5 μm, then The ink was prepared by filtering through a 1.2 μm filter. The obtained ink had a viscosity of 9.4 and a pH of 7.6.

[Evaluation Example 3]
Using the ink of Example 6, in the same manner as in Evaluation Example 1, printing was performed on the washed stainless steel plate so as to be 2 cm × 2 cm and a dry thickness of 10 μm. As a result, there was no clogging of the head and ejection was possible without any problem. Subsequently, it dried at 80 degreeC for 5 minute (s), and the film | membrane was hardened by irradiating an ultraviolet-ray with a UV irradiation apparatus (metal halide lamp 120W). Next, etching, washing, and alkali development were performed in the same manner as in Evaluation Example 1. In the etching, even if other resin components are contained, the adhesion is high due to the carboxyl group of the AB block polymer contained in the ink, and there is no peeling. On the other hand, in alkali development, the B chain has a high acidity. By being a valence, it peeled easily and the alkali developability was also good.

  As described above, according to the ink of Example 6 in which the AB block polymer is contained in the ink, it is water-based and has a low viscosity, so that good printing can be performed by inkjet, etching resistance, and alkali developability. It is possible to obtain an excellent resist film. In order to draw a more delicate line drawing, the aqueous inkjet ink composition for etching resists of this example is useful.

  By using the aqueous inkjet ink composition for etching resists of the present invention, it becomes possible to use inkjet printing capable of fine printing, and as a result, metal processing that requires more delicate and fine line drawing more easily. Image formation and pattern formation are possible for electronic circuits, printed circuit boards, plate making, semiconductor fields, color filters, and the like. As a result, it becomes possible to easily cope with the miniaturization of parts accompanying the rapid development of information-oriented equipment and highly-designed metal plates. Expected to reach

Claims (6)

An etching resist ink printed by an ink jet printing method, comprising at least water, a water-soluble organic solvent, and a polymer,
The polymer is
Obtained by addition polymerization of an α, β unsaturated bond-containing monomer and having at least an α, β unsaturated bond-containing monomer having a carboxyl group as a constituent, its acid value is 50 to 250 mgKOH / g, and the number thereof average molecular weight is 2,000～20,00 0,
Furthermore, the form of the polymer in the ink is an aqueous dispersion or emulsion having an average particle size of 10 nm to 200 nm by neutralizing at least a part of the acid value of the polymer. the form of polymer after the sum is neutralized to the aqueous dispersion or emulsion, at least a portion of the acid value of the polymer derived from the carboxyl group, ammonia; mono- or di- or trialkyl (number of carbon atoms 1-4) amine; monoalkanol (carbon number 2 or 3) amine; mono- or dialkyl (carbon number 1-4) monoalkanol (carbon number 2 or 3) at least one compound selected from the group consisting of amines are in such a that the polymer is neutralized so as not to water-soluble,
An aqueous inkjet ink composition for etching resists , wherein the viscosity of the ink is 2 to 20 mPa · s . 2. The aqueous inkjet ink composition for etching resist according to claim 1, having a pH of 5 to 8.2 and a viscosity of 3 to 10 mPa · s at 25 ° C. 3 .   The water-based inkjet ink composition for an etching resist according to claim 1, wherein a weight average molecular weight / number average molecular weight, which is a molecular weight distribution of the polymer, is 1.6 or less.   The polymer has an AB block copolymer structure, the polymer block of A has an acid value of 0 to 50 mgKOH / g and a number average molecular weight of 1,000 to 5,000, and the polymer block of B The acid value is 50-200 mgKOH / g, and the number average molecular weight is 1,000-15,000, The aqueous inkjet ink composition for etching resists of any one of Claims 1-3.   Furthermore, the water-based inkjet ink composition for etching resists of any one of Claims 1-4 which contain dye or a pigment as a coloring agent component.   Furthermore, the aqueous inkjet ink composition for etching resists of any one of Claims 1-5 which contain an aqueous | water-based ultraviolet curable monomer and / or oligomer as a hardening component.