JP7131722B2 - Coating agent for paper substrates or plastic substrates, and paper substrates, plastic substrates, containers and packaging materials having coating layers of the coating agents - Google Patents

Description

TECHNICAL FIELD The present invention relates to a coating agent for paper substrates or plastic substrates that can be used as gravure ink or flexographic ink for flexible packaging.

In recent years, there has been a demand for imparting functionality to the surface of various substrates, and it is necessary to improve the surface properties of plastic materials, molded articles, paper substrates, film substrates, packaging materials, and the like. As a method for imparting these functions to the substrate surface, a method of attaching a polymer film or the like having various functions to the surface is widely known. However, this method requires a lot of time and effort to attach the film, is often inadequate in adhesion to the substrate and in workability, and is expensive in terms of cost.
On the other hand, methods of expressing these functions by coating are also known as methods of imparting functionality to the surface of these substrates. The coating method is highly convenient because it can be applied not only to the base material before molding and processing, but also to the base material after molding and processing, and only to the desired part. It is often less tolerant.
Film substrates such as polyester film, nylon film, and polyolefin film, which are often used as substrates for food packaging and consumer coatings in daily life, are water repellent, oil repellent, antifouling, antistatic, antireflection, anti-scratch, etc. In addition to physical functionality, recently, hygienic functions such as antibacterial and antiviral functions are also desired, especially antiviral ( Virus inactivation) countermeasures are an urgent need.
As a coating agent having antiviral performance, for example, an antiviral coating agent containing one or more oxides selected from silver, zinc and copper and a double salt of molybdenum oxide is known (for example, Patent Document 1 reference).

As an antiviral material, for example, a photocatalyst is known, and for example, a cloth to which an antiviral material such as a photocatalyst is adhered is known (see, for example, Patent Document 1). However, a coating agent using a photocatalyst is not yet known.

JP 2018-172306 A JP 2017-155368 A

An object of the present invention is to provide a coating agent for paper substrates or plastic substrates that can easily impart antiviral properties to substrates such as plastic materials, molded articles, film substrates and packaging materials.

That is, the present invention contains a binder resin (A), a photocatalyst (B), and an organic solvent, wherein the photocatalyst (B) contains titanium oxide containing crystalline rutile-type titanium oxide and a divalent copper compound, The crystalline rutile-type titanium oxide has a full width at half maximum of 0.65 degrees or less of the strongest diffraction peak corresponding to rutile-type titanium oxide in an X-ray diffraction pattern in which the diffraction line intensity is plotted against the diffraction angle 2θ by Cu-Kα rays. and a photocatalyst in which the content of the crystalline rutile-type titanium oxide in the titanium oxide is 50 mol% or more and the content of the anatase-type titanium oxide is less than 50 mol%, and the total solid content of the coating agent In contrast, a coating agent for paper substrates or plastic substrates containing 0.5 to 80% by mass of the photocatalyst (B) is provided.

The present invention also provides a paper substrate or a plastic substrate obtained by coating a paper substrate or a film with the coating agent described above.

The present invention also provides containers and packaging materials using the above-described paper base material or plastic base material.

According to the present invention, substrates such as plastic materials, molded articles, film substrates, paper substrates, and packaging materials can be easily imparted with antiviral properties by coating.

(Definition of words)
In the present invention, all "parts" indicate "mass parts", "coating agent total amount" indicates the total amount of ink containing all volatile components such as organic solvents, and "coating agent solid content total amount" , indicates the total amount of non-volatile components only, without volatile components.

(Binder resin (A))
Examples of the binder resin (A) used in the coating agent for paper substrates or plastic substrates of the present invention include cellulose-based resins such as cellulose acetate propionate (CAP) and cellulose acetate butyronate (CAB). cellulose resin, polyamide resin, urethane resin, acrylic resin, vinyl chloride-vinyl acetate copolymer resin, chlorinated polypropylene resin, ethylene-vinyl acetate copolymer resin, vinyl acetate resin, polyvinyl chloride resin, etc. Examples include vinyl chloride resins, polyester resins, alkyd resins, rosin resins, rosin-modified maleic acid resins, ketone resins, cyclized rubbers, chlorinated rubbers, butyral, and petroleum resins.

(Fibrous resin)
Examples of cellulose-based resins include cellulose acetate propionate, cellulose acetate butyrate and other cellulose ester resins, nitrocellulose (also referred to as nitrocellulose), hydroxyalkylcellulose, and carboxyalkylcellulose. The cellulose ester resin preferably has an alkyl group, and examples of the alkyl group include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, pentyl group, hexyl group and the like. may have a substituent.
As the cellulose resin, among the above, cellulose acetate propionate, cellulose acetate butyrate, and nitrocellulose are preferable. Nitrocellulose is particularly preferred. As for the molecular weight, a weight average molecular weight of 5,000 to 200,000 is preferable, and 10,000 to 50,000 is more preferable. Further, those having a glass transition temperature of 120° C. to 180° C. are preferable. When the polyurethane resin (A) of the present invention is used in combination, it can be expected that blocking resistance, scratch resistance and other physical properties of the ink film are improved.
Nitrocellulose (nitrocellulose) is obtained as a nitric ester obtained by reacting natural cellulose with nitric acid to replace three hydroxyl groups in the 6-membered ring of the anhydride glucopyranose group in natural cellulose with nitric acid groups. preferable.

By using nitrocellulose (nitrocellulose), high dispersibility in pigments can be obtained, so if it is used as a coating agent for surface printing, it is suitable because it can improve the strength of the printing ink coating film. . The nitrocellulose (nitrocellulose) preferably has a nitrogen content of 10 to 13% by mass and an average polymerization degree of 30 to 500, more preferably a nitrogen content of 10 to 13% by mass and an average polymerization degree of 45 to 290. .

The amount of nitrocellulose (nitrocellulose) added is preferably 0.15 to 40% by mass, more preferably 1.0 to 35% by mass, based on the total amount of the ink.

(polyamide resin)
The polyamide resin is, for example, an organic solvent-soluble thermoplastic polyamide obtained by polycondensation of a polybasic acid and a polyvalent amine. In particular, a polyamide resin containing a reaction product of an acid component containing a polymerized fatty acid and/or a dimer acid and an aliphatic and/or aromatic polyamine is preferred, and further contains a portion of primary and secondary monoamines. is preferred.
Polybasic acids used as raw materials for polyamide resins include, but are not limited to, adipic acid, sebacic acid, azelaic acid, phthalic anhydride, isophthalic acid, suberic acid, glutaric acid, fumaric acid, and pimeline. acid, oxalic acid, malonic acid, succinic acid, maleic acid, terephthalic acid, 1,4-cyclohexyldicarboxylic acid, trimellitic acid, dimer acid, hydrogenated dimer acid, polymerized fatty acids, etc. Among them, dimer acid or polymerized A polyamide resin containing a structure derived from a fatty acid as a main component (50% by mass or more in the polyamide resin) is preferred. Here, the polymerized fatty acid is obtained by a cyclization reaction of an unsaturated fatty acid or the like, and includes a monobasic fatty acid, a dimerized polymerized fatty acid (dimer acid), a trimerized polymerized fatty acid, and the like. Fatty acids constituting the dimer acid or polymerized fatty acid are preferably derived from natural oils such as soybean oil, palm oil and rice bran oil, and are preferably obtained from oleic acid and linoleic acid.
A monocarboxylic acid can also be used together with a polybasic acid. Monocarboxylic acids used in combination include acetic acid, propionic acid, lauric acid, palmitic acid, benzoic acid, and cyclohexanecarboxylic acid.

Polyamines include polyamines, primary or secondary monoamines, and the like. Examples of polyamines used in polyamide resins include aliphatic diamines such as ethylenediamine, propylenediamine, hexamethylenediamine and methylaminopropylamine, and aliphatic polyamines such as diethylenetriamine and triethylenetetramine. , cyclohexylene diamine, isophorone diamine, and the like. Examples of araliphatic polyamines include xylylenediamine, and examples of aromatic polyamines include phenylenediamine and diaminodiphenylmethane. Further, primary and secondary monoamines include n-butylamine, octylamine, diethylamine, monoethanolamine, monopropanolamine, diethanolamine, dipropanolamine, and the like.
The amount of polyamide resin added is preferably 0.15 to 40% by mass, more preferably 1.0 to 35% by mass, based on the total amount of the ink.

(urethane resin)
The urethane resin is not particularly limited as long as it is a polyurethane resin obtained by reacting a polyol and a polyisocyanate. As the polyol, for example, various known polyols that are commonly used in the production of polyurethane resins can be used, and one or more of them may be used in combination. For example, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3-propanediol, 2-ethyl-2butyl-1,3-propanediol, 1,3-butanediol , 1,4-butanediol, neopentyl glycol, pentanediol, 3-methyl-1,5-pentanediol, hexanediol, octanediol, 1,4-butynediol, 1,4-butylenediol, diethylene glycol, triethylene glycol , dipropylene glycol, glycerin, trimethylolpropane, trimethylolethane, 1,2,6-hexanetriol, 1,2,4-butanetriol, sorbitol, pentaerythritol, and other saturated or unsaturated low-molecular-weight polyols (1) these low-molecular-weight polyols (1), sebacic acid, adipic acid, phthalic acid, isophthalic acid, terephthalic acid, maleic acid, fumaric acid, succinic acid, oxalic acid, malonic acid, glutaric acid, pimelic acid Polyester polyols (2) obtained by dehydration condensation or polymerization of polyvalent carboxylic acids such as , spelic acid, azelaic acid, trimellitic acid and pyromellitic acid, or anhydrides thereof; cyclic ester compounds such as polycaprolactone, Polyester polyols (3) obtained by ring-opening polymerization of lactones such as polyvalerolactone and poly(β-methyl-γ-valerolactone); Polycarbonate polyols obtained by reaction with diphenyl carbonate, ethylene carbonate, phosgene, etc. (4); Polybutadiene glycols (5); Glycols obtained by adding ethylene oxide or propylene oxide to bisphenol A (6); 1 molecule Acrylic obtained by copolymerizing one or more of hydroxyethyl, hydroxypropyl acrylate, acrylic hydroxybutyl, etc., or their corresponding methacrylic acid derivatives, etc. with, for example, acrylic acid, methacrylic acid, or an ester thereof and polyol (7).

Examples of polyisocyanates include various known aromatic diisocyanates, aliphatic diisocyanates, alicyclic diisocyanates, and the like, which are generally used in the production of polyurethane resins. For example, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 1-methyl-2,4-phenylene diisocyanate, 1-methyl-2,6-phenylene diisocyanate, 1-methyl-2,5-phenylene diisocyanate, 1 -methyl-2,6-phenylene diisocyanate, 1-methyl-3,5-phenylene diisocyanate, 1-ethyl-2,4-phenylene diisocyanate, 1-isopropyl-2,4-phenylene diisocyanate, 1,3-dimethyl-2 ,4-phenylene diisocyanate, 1,3-dimethyl-4,6-phenylene diisocyanate, 1,4-dimethyl-2,5-phenylene diisocyanate, diethylbenzene diisocyanate, diisopropylbenzene diisocyanate, 1-methyl-3,5-diethylbenzene diisocyanate, 3-methyl-1,5-diethylbenzene-2,4-diisocyanate, 1,3,5-triethylbenzene-2,4-diisocyanate, naphthalene-1,4-diisocyanate, naphthalene-1,5-diisocyanate, 1-methyl -naphthalene-1,5-diisocyanate, naphthalene-2,6-diisocyanate, naphthalene-2,7-diisocyanate, 1,1-dinaphthyl-2,2'-diisocyanate, biphenyl-2,4'-diisocyanate, biphenyl-4 ,4'-diisocyanate, 3-3'-dimethylbiphenyl-4,4'-diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,2'-diphenylmethane diisocyanate, diphenylmethane-2,4-diisocyanate and other aromatic polyisocyanates ; tetramethylene diisocyanate, hexamethylene diisocyanate, dodecamethylene diisocyanate, trimethylhexamethylene diisocyanate, 1,3-cyclopentylene diisocyanate, 1,3-cyclohexylene diisocyanate, 1,4-cyclohexylene diisocyanate, 1,3-di(isocyanate methyl)cyclohexane, 1,4-di(isocyanatomethyl)cyclohexane, lysine diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 2,4'-dicyclohexylmethane diisocyanate, 2,2'-dicyclohexylmethane diisocyanate, 3, 3'-dimethyl-4,4'-dicyclohexylmethane Aliphatic or alicyclic polyisocyanates such as diisocyanates can be used. These polyisocyanates may be used alone or in combination of two or more. Among these, these diisocyanate compounds can be used alone or in combination of two or more.

A chain extender can also be used. Examples of chain extenders include ethylenediamine, propylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, isophoronediamine, dicyclohexylmethane-4,4′-diamine, 2-hydroxyethylethylenediamine and 2-hydroxyethylpropyldiamine. , 2-hydroxyethylpropylenediamine, di-2-hydroxyethylethylenediamine, di-2-hydroxyethylenediamine, di-2-hydroxyethylpropylenediamine, 2-hydroxypyropyrethylenediamine, di-2-hydroxypyropyrethylenediamine, di- Amines having a hydroxyl group in the molecule such as 2-hydroxypropylethylenediamine can also be used. These chain extenders can be used alone or in combination of two or more.

A monovalent active hydrogen compound can also be used as a terminal blocker for the purpose of terminating the reaction. Examples of such compounds include dialkylamines such as di-n-butylamine and alcohols such as ethanol and isopropyl alcohol. Furthermore, amino acids such as glycine and L-alanine can be used as a reaction terminator, especially when it is desired to introduce a carboxyl group into the polyurethane resin. These terminal blocking agents can be used alone or in combination of two or more.
The weight average molecular weight of the urethane resin is preferably from 10,000 to 100,000, more preferably from 15,000 to 80,000.
The amount of urethane resin added is preferably 0.15 to 40% by mass, more preferably 1.0 to 35% by mass, based on the total amount of the ink.

(acrylic resin)
The acrylic resin is not particularly limited as long as it is obtained by copolymerizing a polymerizable monomer containing (meth)acrylic acid ester as a main component. Examples of polymerizable monomers include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, iso-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n - octyl (meth)acrylate, iso-octyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, iso-nonyl (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, methoxyethyl ( meth)acrylate, ethoxyethyl (meth)acrylate, phenoxyethyl (meth)acrylate and the like. The polymerization method is also not particularly limited, and those obtained by known bulk polymerization, solution polymerization, emulsion polymerization, suspension polymerization, or the like can be used.
The acrylic resin preferably has a weight average molecular weight of 5,000 to 200,000, more preferably 10,000 to 100,000.
The amount of acrylic resin to be added is preferably 0.15 to 40% by mass, more preferably 1.0 to 35% by mass, based on the total amount of the ink.

(polyester resin)
The polyester resin is not particularly limited as long as it is a polyester resin obtained by reacting an alcohol and a carboxylic acid using a known esterification polymerization reaction.
Alcohols include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3-propanediol, 2-ethyl-2butyl-1,3-propanediol, 1,3-butane Diol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, 1,2-pentanediol, 3-methyl-1,5-pentanediol, hexanediol, octanediol, 1,4-butynediol , 1,4-butylene diol, diethylene glycol, triethylene glycol, dipropylene glycol, glycerin, trimethylolpropane, trimethylolethane, 1,2,6-hexanetriol, 1,2,4-butanetriol, sorbitol, pentaes litol, 1,4-cyclohexanediol, 1,2-cyclohexanediol, 1,4-cyclohexanedimethanol, 1,2-cyclohexanedimethanol, spiroglycol, isosorbide and the like. These can be used alone or in combination of two or more. Among them, polyfunctional alcohols are preferred.
Carboxylic acids include formic acid, acetic acid, propionic acid, butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, oleic acid, linoleic acid, oxalic acid, and malonic acid. , succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, phthalic acid, 1,4-cyclohexanedicarboxylic acid and the like. These can be used alone or in combination of two or more. Among them, polyfunctional carboxylic acids are preferred.
The weight average molecular weight of the polyester resin is preferably 500-6000. It is more preferably 1400 to 5500. The amount of the polyester resin added is preferably 0.15 to 40% by mass, more preferably 1.0 to 35% by mass, based on the total amount of the ink.

(vinyl chloride-vinyl acetate copolymer resin)
The vinyl chloride-vinyl acetate copolymer resin is not particularly limited as long as it is a copolymer of vinyl chloride and vinyl acetate. As for the molecular weight, a weight average molecular weight of 5,000 to 100,000 is preferable, and 10,000 to 70,000 is more preferable. The structure derived from the vinyl acetate monomer is preferably 1 to 30% by mass, and the structure derived from the vinyl chloride monomer is preferably 70 to 95% by mass, based on 100% by mass of the solid content of the vinyl chloride-vinyl acetate copolymer resin. In this case, the solubility in organic solvents is improved, and the adhesion to substrates, film physical properties, scratch resistance and the like are improved.
From the viewpoint of solubility in organic solvents, those containing a hydroxyl group derived from a vinyl alcohol structure are also preferred. The hydroxyl value is preferably 20-200 mgKOH/g. Also, the glass transition temperature is preferably 50°C to 90°C.
The amount of the vinyl chloride-vinyl acetate copolymer resin added is preferably 0.15 to 40% by mass, more preferably 1.0 to 35% by mass, based on the total amount of the ink.

(rosin resin)
The rosin-based resin is not particularly limited as long as it has a rosin skeleton, but rosin-modified maleic acid resin, rosin ester, rosin phenol, polymerized rosin, and the like are preferable. It preferably has a softening point (by the ring and ball method) of 90 to 200°C.
Among them, cellulose-based resins, polyamide-based resins, urethane-based resins, acrylic-based resins, and vinyl chloride-based resins are preferred. In particular, it is preferable to contain at least two kinds of binder resins.
Preferably, it is a combination selected from urethane-based resin/vinyl chloride-based resin, urethane-based resin/cellulose-based resin, polyamide-based resin/cellulose-based resin, acrylic resin/cellulose-based resin, and the binder resin (A) In 100% by mass, the total content of the two resins is preferably 80 to 100% by mass, more preferably 90 to 100% by mass.

Further, urethane-based resin/vinyl chloride-based resin, urethane-based resin/fiber-based resin, polyamide-based resin/fiber-based resin, and acrylic-based resin/fiber-based resin have a mass ratio of 95/5 to 20/80, respectively. is preferably More preferably, the mass ratio is 90/10 to 50/50. This combination provides excellent basic performance desired for coating agents, such as abrasion resistance, blocking resistance, heat resistance, and oil resistance.

(curing agent)
Moreover, you may use a hardening|curing agent together with binder resin (A). As the curing agent, general-purpose curing agents for organic solvent-based gravure inks may be used, but isocyanate-based curing agents are most frequently used.
The amount of the isocyanate compound added is preferably in the range of 0.3% by mass to 10.0% by mass based on the solid content of the liquid printing ink from the viewpoint of curing efficiency, and if it is 1.0% by mass to 7.0% by mass. more preferred.
The binder resin (A) is preferably in the range of 0.15 to 50% by mass, more preferably in the range of 1 to 40% by mass, relative to the coating agent for paper substrates or plastic substrates of the present invention. is most preferred.

(Photocatalyst (B))
The photocatalyst (B) is a photocatalyst containing titanium oxide containing crystalline rutile-type titanium oxide and a divalent copper compound, wherein the crystalline rutile-type titanium oxide is a diffraction line with respect to the diffraction angle 2θ by Cu-Kα rays. In an X-ray diffraction pattern in which the intensity is plotted, the full width at half maximum of the strongest diffraction peak corresponding to rutile-type titanium oxide is titanium oxide having a full width at half maximum of 0.65 degrees or less, and the crystalline rutile-type titanium oxide is contained in the titanium oxide. The photocatalyst has an amount of 50 mol % or more and an anatase type titanium oxide content of less than 50 mol %.

A photocatalyst (visible A visible-light-responsive photocatalyst having photocatalytic activity such as antiviral properties in the light region can be obtained. Moreover, unlike monovalent copper compounds, divalent copper compounds are less susceptible to discoloration due to oxidation, so discoloration over time can be suppressed.

In the present invention, "bright place" means a place where visible light exists, and "dark place" means a place where light does not exist.

Here, photocatalytic activity means at least one selected from photoinduced decomposability and photoinduced hydrophilization. Photoinduced decomposability is the action of oxidatively decomposing organic substances adsorbed on the surface treated with titanium oxide. It is an effect that becomes This photo-induced hydrophilization is thought to be caused by the increase in hydroxyl groups on the surface of titanium oxide due to holes generated and diffused by photoexcitation.

Viruses mean DNA viruses and RNA viruses, but also include bacteriophages (hereinafter sometimes abbreviated as "phages"), which are viruses that infect bacteria.

Next, each component of the photocatalyst (B) will be described.
(titanium oxide)
The titanium oxide used for the photocatalyst (B) contains crystalline rutile-type titanium oxide.

In the present invention, crystalline rutile-type titanium oxide means that the full width at half maximum of the strongest diffraction peak corresponding to rutile-type titanium oxide in an X-ray diffraction pattern in which the diffraction line intensity is plotted against the diffraction angle 2θ by Cu-Kα rays is 0. It means titanium oxide of 0.65 degrees or less.

If the full width at half maximum is larger than 0.65 degrees, the crystallinity will be poor and the antiviral properties in the dark will be insufficient. From this viewpoint, the full width at half maximum is preferably 0.6 degrees or less, more preferably 0.5 degrees or less, still more preferably 0.4 degrees or less, and even more preferably 0.35 degrees. .

The content of crystalline rutile-type titanium oxide (hereinafter sometimes referred to as “rutilization rate”) in titanium oxide is 50 mol % or more. When the content is 50 mol% or more, the resulting photocatalyst has sufficient antiviral properties in bright and dark places, and also has sufficient organic compound degradability in bright places and, in particular, sufficient visible light responsiveness. become a thing. From this point of view, the rutilization rate is preferably 90 mol % or more, more preferably 94 mol % or more. This rutilization rate is a value measured by XRD as described later.

From the above viewpoint, the content of anatase-type titanium oxide in titanium oxide (hereinafter sometimes referred to as "anatase conversion rate") is preferably small, and the anatase conversion rate is less than 50 mol%, preferably 10 mol. %, more preferably less than 7 mol %, and still more preferably 0 mol % (that is, it does not contain anatase titanium oxide). This anatase rate is also a value measured by XRD, like the rutilization rate.

The specific surface area of titanium oxide is preferably 1-200 m ² /g. When the specific surface area is 1 m ² /g or more, the frequency of contact with viruses, bacteria and organic compounds increases due to the large specific surface area, and the obtained photocatalyst has antiviral properties in bright and dark places, organic compound degradability and antibacterial properties. excellent in nature. On the other hand, when it is 200 m ² /g or less, the handleability is excellent. From these points of view, the specific surface area of titanium oxide is more preferably 3 to 100 m ² /g, still more preferably 4 to 70 m ² /g, particularly preferably 8 to 50 m ² /g. Here, the specific surface area is a value measured by the BET method using nitrogen adsorption.

Titanium oxide is classified into those produced by a vapor phase method and those produced by a liquid phase method, and both of them can be used, but the titanium oxide produced by a vapor phase method is more preferable.

The vapor phase method is a method of obtaining titanium oxide by a vapor phase reaction with oxygen using titanium tetrachloride as a raw material. Titanium oxide obtained by the gas phase method has a uniform particle size and high crystallinity because it is manufactured through a high-temperature process. As a result, the obtained photocatalyst has good antiviral properties in bright and dark places, organic compound decomposing properties, and antibacterial properties.

On the other hand, the liquid phase method is a method of obtaining titanium oxide by hydrolyzing or neutralizing a liquid in which titanium oxide raw materials such as titanium chloride and titanyl sulfate are dissolved. Titanium oxide produced by the liquid phase method tends to have low rutile crystallinity and a large specific surface area. , the vapor phase method is more suitable because it takes time and effort.

As the titanium oxide, it is more advantageous to use commercially available titanium oxide as it is in consideration of the catalyst preparation process.

(Divalent copper compound)
The photocatalyst (B) contains a divalent copper compound. This divalent copper compound alone does not have antiviral properties in bright and dark places, organic compound degradability in bright places, and visible light responsiveness. And the antiviral properties in the dark, the organic compound degradability in the light, and the visible light responsiveness are fully expressed. In addition, since the divalent copper compound is less discolored by oxidation or the like than the monovalent copper compound, discoloration of the photocatalyst using the divalent copper compound is suppressed.

The divalent copper compound is not particularly limited, and includes one or two of divalent copper inorganic compounds and divalent copper organic compounds.

Divalent copper inorganic compounds include copper sulfate, copper nitrate, copper iodate, copper perchlorate, copper oxalate, copper tetraborate, copper ammonium sulfate, copper amidosulfate and copper ammonium chloride, copper pyrophosphate and copper carbonate. 1 selected from the group consisting of divalent copper inorganic acid salts, divalent copper halides consisting of copper chloride, copper fluoride and copper bromide, and copper oxide, copper sulfide, azurite, malachite and copper azide species or two or more species.

Divalent copper organic compounds include carboxylates of divalent copper. The divalent copper carboxylates include copper formate, copper acetate, copper propionate, copper butyrate, copper valerate, copper caproate, copper enanthate, copper caprylate, copper pelargonate, copper caprate, and mystic acid. Copper, copper palmitate, copper margarate, copper stearate, copper oleate, copper lactate, copper malate, copper citrate, copper benzoate, copper phthalate, copper isophthalate, copper terephthalate, copper salicylate, mellitic acid Copper, copper oxalate, copper malonate, copper succinate, copper glutarate, copper adipate, copper fumarate, copper glycolate, copper glycerate, copper gluconate, copper tartrate, copper acetylacetonate, copper ethylacetoacetate, copper isokyl One selected from the group consisting of copper herbate, copper β-resorcylate, copper diacetoacetate, copper formylsuccinate, copper salicylate, copper bis(2-ethylhexanoate), copper sebacate and copper naphthenate, or Two or more types are mentioned. Other divalent copper organic compounds selected from the group consisting of copper oxine, copper acetylacetone, copper ethylacetoacetate, copper trifluoromethanesulfonate, copper phthalocyanine, copper ethoxide, copper isopropoxide, copper methoxide, and copper dimethyldithiocarbamate. 1 type or 2 types or more are mentioned.

Among the above divalent copper compounds, preferably one or more of copper oxide, divalent copper halide, divalent copper inorganic acid salt and divalent copper carboxylate, for example, divalent copper They are one or more of halides, inorganic acid salts of divalent copper and carboxylates of divalent copper.

Moreover, as a bivalent copper compound, the bivalent copper compound represented with the following general formula (1) is mentioned.
Cu2 ₍ OH) _3X (1)

In the general formula (1), X is an anion, preferably a halogen such as Cl, Br, or I, a conjugate base of a carboxylic acid such as CH ₃ COO, or an inorganic acid such as NO ₃ or (SO ₄ ) _1/2 or OH.

Among these divalent copper compounds, a divalent copper inorganic compound is more preferable, and copper oxide is still more preferable, from the viewpoint of economy because it contains less impurities. A divalent copper compound represented by the general formula (1) is also preferred. The divalent copper compound may be either an anhydride or a hydrate.

The content of the divalent copper compound in terms of copper is preferably 0.01 to 20 parts by mass with respect to 100 parts by mass of the titanium oxide. When the amount is 0.01 part by mass or more, good antiviral properties, organic compound decomposing properties, and antibacterial properties are obtained in bright and dark places. In addition, when the amount is 20 parts by mass or less, the surface of the titanium oxide is prevented from being coated, and the function as a photocatalyst (organic compound decomposability, antibacterial properties, etc.) is well expressed, and antiviral performance is achieved with a small amount. It can be improved and is economical. From this point of view, the content of the divalent copper compound in terms of copper is more preferably 0.1 to 20 parts by mass, more preferably 0.1 to 15 parts by mass with respect to 100 parts by mass of titanium oxide, Even more preferably, it is 0.3 to 10 parts by mass.

Here, the copper-equivalent content of the divalent copper compound with respect to 100 parts by mass of titanium oxide can be calculated from the charged amounts of the raw material of the divalent copper compound and the raw material of titanium oxide. In addition, this content in terms of copper can also be specified by measuring the photocatalyst by ICP (inductively coupled plasma) emission spectrometry, which will be described later.

As described above, the photocatalyst (B) contains, as essential components, titanium oxide containing crystalline rutile-type titanium oxide and a divalent copper compound, but other optional components within a range that does not impede the object of the present invention. may contain. However, from the viewpoint of improving the function as a photocatalyst and antiviral performance, the content of the essential component in the photocatalyst (B) is preferably 90% by mass or more, more preferably 95% by mass or more, and further It is preferably 99% by mass or more, more preferably 100% by mass.

The photocatalyst (B) can be produced by performing a mixing step of mixing titanium oxide containing crystalline rutile-type titanium oxide and a divalent copper compound raw material. Moreover, a heat treatment step of heat-treating the mixture obtained by this mixing step may be further performed to obtain a photocatalyst. A photocatalyst can also be obtained by suspending and adsorbing titanium oxide in an aqueous solution of a copper compound. Specifically, the photocatalyst (B) can be produced by the method described in Japanese Patent No. 5,343,176.

It is preferable that the photocatalyst (B) has a primary particle size of about 200 to 400 nm and a secondary particle size of about 3 to 10 μm, because it can be dispersed in a coating agent and has excellent photocatalytic activity such as antiviral properties.
The method of measuring the primary particle size is a value obtained by directly measuring the size of primary particles from an electron micrograph using a transmission electron microscope (TEM).
In order to express photocatalytic activity such as antiviral properties, the photocatalyst (B) is preferably contained in an amount of 0.5% by mass or more relative to the total solid content of the coating agent for paper substrates or plastic substrates of the present invention. , preferably 1% by mass or more, preferably 5% by mass or more, and preferably 10% by mass or more. On the other hand, in order to prevent deterioration of adhesion and abrasion resistance, the photocatalyst (B) is preferably contained in an amount of 80% by mass or less with respect to the total solid content of the coating agent for paper substrates or plastic substrates of the present invention. The content is preferably 55% by mass or less, preferably 50% by mass or less, preferably 30% by mass or less, and most preferably 20% by mass or less.

(Organic solvent (C))
The organic solvent (C) used in the coating agent for paper substrates or plastic substrates of the present invention is not particularly limited. organic solvents, aliphatic hydrocarbon organic solvents such as hexane, methylcyclohexane, heptane, octane, and decane; methyl acetate, ethyl acetate, isopropyl acetate, normal propyl acetate, butyl acetate, amyl acetate, ethyl formate, butyl propionate, Various ester-based organic solvents can be used. Water-miscible organic solvents include alcohols such as methanol, ethanol, propanol, butanol and isopropyl alcohol, ketones such as acetone, methyl ethyl ketone and cyclohaxanone, ethylene glycol (mono, di) methyl ether, and ethylene glycol (mono, di) ethyl. Ether, ethylene glycol monopropyl ether, ethylene glycol monoisopropyl ether, monobutyl ether, diethylene glycol (mono, di) methyl ether, diethylene glycol (mono, di) ethyl ether, diethylene glycol monoisopropyl ether, diethylene glycol monobutyl ether, triethylene glycol (mono, Di)methyl ether, propylene glycol (mono, di)methyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol (mono, di)methyl ether, and other glycol ether organic solvents can be used. These may be used alone or in combination of two or more.

In terms of work hygiene during printing and the toxicity of packaging materials, use ethyl acetate, propyl acetate, isopropanol, normal propanol, etc., and do not use aromatic solvents such as toluene or ketone solvents such as methyl ethyl ketone. is more preferred.

Among them, a mixture of isopropyl alcohol/ethyl acetate/methoxypropanol is more preferable from the viewpoint of solubility in polyurethane resin and nitrocellulose. For drying adjustment, glycol ethers can be added as long as they are less than 10 mass % of the total amount of the ink.
The coating agent for paper substrates or plastic substrates of the present invention also contains wax, a chelate cross-linking agent, an extender, a leveling agent, an antifoaming agent, Plasticizers, infrared absorbers, ultraviolet absorbers, fragrances, flame retardants, and the like may also be included.

(Method for producing coating agent for paper substrate or plastic substrate)
The coating agent for paper substrates or plastic substrates of the present invention can be produced by dissolving and/or dispersing the binder resin (A), the photocatalyst (B), etc. in an organic solvent. As the dispersing machine, commonly used roller mills, ball mills, pebble mills, attritors, sand mills and the like can be used.

The coating agent for paper substrates or plastic substrates of the present invention can be coated on substrates such as plastic materials, molded articles, film substrates, and packaging materials by general coating methods. Roll coating (gravure coater), flexo roll coating (flexo coater), reverse roll coating, wire bar coating, lip coating, air knife coating, curtain flow coating, spray coating, immersion coating, brush coating and the like can be employed. Among them, from an industrial point of view, it is preferable to use gravure roll coating (gravure coater) and flexo roll coating (flexo coater).

Also, a coating layer may be provided on a substrate by impregnating the substrate with the overcoating agent of the present invention.
When the coating agent of the present invention is coated using a gravure coater, the viscosity may be 12 to 30 seconds at 25 ° C. using Zahn cup # 3 manufactured by Rigosha, more preferably 15 to 20 seconds. be.
Further, when the coating agent of the present invention is coated using a flexo coater, the viscosity may be 7 to 40 seconds at 25 ° C. using Zahn Cup #4 manufactured by Rigosha, more preferably 10 to 20. seconds.

The thickness of the coating layer of the present invention can be appropriately adjusted depending on the application and the material of the base material. preferable.

Since the coating agent for paper substrates or plastic substrates of the present invention has excellent dispersibility, the coating layer formed using the coating agent has a structure in which part of the photocatalyst (B) is exposed. Cheap. Therefore, the coating layer in the present invention can maximize the antiviral function.

(Paper substrate or plastic substrate coating agent of the present invention)
The substrates used in the present invention are paper substrates or plastic substrates.

(Paper substrate)
The paper substrate is produced by a known paper machine using natural fibers for papermaking such as wood pulp, but the papermaking conditions are not particularly specified. Examples of natural fibers for papermaking include wood pulp such as softwood pulp and hardwood pulp, non-wood pulp such as Manila hemp pulp, sisal pulp and flax pulp, and pulp obtained by chemically modifying these pulps. The types of pulp that can be used include chemical pulp, ground pulp, chemi-grand pulp, thermomechanical pulp, and the like prepared by sulfate cooking, acid/neutral/alkaline sulfite cooking, soda salt cooking, and the like.
Moreover, various types of commercially available fine paper, coated paper, lined paper, impregnated paper, cardboard, paperboard, etc. can also be used.

(Plastic substrate)
The plastic substrate may be a substrate used for substrates such as plastic materials, molded articles, film substrates, packaging materials, etc. In particular, gravure roll coating (gravure coater), flexo roll coating (flexo coater) In the case of using , a film substrate commonly used in the field of gravure and flexographic printing can be used as it is.
Specifically, for example, polyamide resins such as nylon 6, nylon 66, nylon 46, polyethylene terephthalate (hereinafter sometimes referred to as PET), polyethylene naphthalate, polytrimethylene terephthalate, polytrimethylene naphthalate, polybutylene terephthalate, Polyester resins such as polybutylene naphthalate, polyhydroxycarboxylic acids such as polylactic acid, biodegradable resins such as aliphatic polyester resins such as poly(ethylene succinate) and poly(butylene succinate), polypropylene, polyethylene, etc. Polyolefin resins, polyimide resins, polyarylate resins, or films made of thermoplastic resins such as polyarylate resins or mixtures thereof, and laminates thereof. Among them, films made of polyethylene terephthalate (PET), polyester, polyamide, polyethylene, and polypropylene can be preferably used. These base films may be either unstretched films or stretched films, and the manufacturing method thereof is not limited. Also, the thickness of the base film is not particularly limited, but it is usually in the range of 1 to 500 μm. Further, the substrate film is preferably subjected to corona discharge treatment, and aluminum, silica, alumina, or the like may be deposited thereon.

The base material is a laminate (sometimes referred to as a laminated film) having a laminated structure obtained by laminating the paper base material or film base material by a dry lamination method, a solventless lamination method, or an extrusion lamination method. I don't mind. In addition, the structure of the laminate may include a metal foil, a metal deposited film layer, an inorganic deposited film layer, an oxygen absorbing layer, an anchor coat layer, a printed layer, a varnish layer, and the like. There are many types of such laminates depending on the application, but the structure most often used for food packaging and daily necessities at present is a paper base material or a film base material expressed as (F), and a printed or varnish layer. is expressed as (P), the metal or inorganic layer of the metal foil and vapor deposition film layer is expressed as (M), the adhesive layer is expressed as (AD), and the hot melt adhesive, heat sealant, and cold sealant are expressed as (AD2 ), the following configuration can be considered as a specific embodiment of the laminated film, but it is of course not limited to this.

(F)/(P)/(F)
(F)/(P)/(AD)/(F),
(F)/(P)/(AD)/(F)/(AD)/(F),
(F)/(P)/(AD)/(M)/(AD)/(F),
(F)/(P)/(AD)/(M),
(F)/(P)/(AD)/(F)/(AD)/(M)/(AD)/(F),
(F)/(P)/(AD)/(M)/(AD)/(F)/(AD)/(F),
(M)/(P)/(AD)/(M),
(M)/(P)/(AD)/(F)/(AD)/(M),
(P)/(F)
(P)/(F)/(P)
(P)/(F)/(AD)/(F),
(P)/(F)/(AD)/(F)/(AD)/(F)
(F)/(P)/(F)/(AD2)
(F)/(P)/(AD2)
(F)/(P)/(AD)/(M)/(AD2)

The single-layer paper substrate or film substrate and the laminate having a laminated structure are functional films, flexible packaging films, shrink films, packaging films for daily necessities, pharmaceutical packaging films, food products, etc., depending on the industry and method of use. Packaging films, cartons, posters, flyers, CD jackets, direct mail, pamphlets, high-quality paper, coated paper, art paper, imitation paper, thin paper, cardboard used for packages of cosmetics, beverages, pharmaceuticals, toys, equipment, etc. and various synthetic papers, but the coating agent for paper substrates or plastic substrates of the present invention can be used without particular limitations. In this case, the coating agent for a paper base material or a plastic base material of the present invention is preferably coated on the outermost surface of a container or packaging material using them.

As described above, as a laminate having a laminated structure, there are many laminates having a printed layer in which a printed layer is applied to a paper base material or a film base material. Of course, the agent can also be preferably coated on a substrate having the printing ink layer.

The printing ink used for the printing ink layer is not particularly limited, and the printing layer can be coated with offset lithographic ink, gravure printing ink, flexographic printing ink, inkjet printing ink, and the like. In particular, when using a coating method such as gravure roll coating (gravure coater) or flexo roll coating (flexo coater), in-line printing is possible, so combining it with gravure printing ink or flexographic printing ink is highly recommended for industrial use. preferred.
Gravure printing inks and flexographic printing inks (hereinafter referred to as liquid printing inks) are formed from printing inks comprising binder resins, pigments, solvents and, if necessary, additives.

(liquid printing ink)
Liquid printing inks used as gravure printing inks and flexographic printing inks are broadly classified into organic solvent-based liquid printing inks containing organic solvents as the main solvent and water-based liquid printing inks containing water as the main solvent.

(Organic solvent-based liquid printing ink)
In the organic solvent-based liquid printing ink, a pigment dispersion is obtained by dispersing a mixture containing the modified pigment used in the present invention, a binder resin, an organic solvent medium, a dispersant, an antifoaming agent, etc., which will be described later, with a disperser. . It can be obtained by adding a resin, an aqueous medium, and, if necessary, an additive such as a leveling agent to the obtained pigment dispersion, and stirring and mixing. As a dispersing machine, a bead mill, eiger mill, sand mill, gamma mill, attritor, etc., which are generally used for the production of gravure and flexographic printing inks, are used.

The ink viscosity of the organic solvent-based liquid printing ink is 10 mPa·s or more from the viewpoint of preventing sedimentation of the pigment and appropriately dispersing it, whether it is used as a gravure ink or a flexographic ink. It is preferably in the range of 1000 mPa·s or less from the viewpoint of workability efficiency during ink production and printing. The above viscosity is measured at 25° C. with a B-type viscometer manufactured by Tokimec.

The viscosity of the ink can be adjusted by appropriately selecting the types and amounts of raw materials used, binder resins, pigments, organic solvents, and the like. Also, the viscosity of the ink can be adjusted by adjusting the particle size and particle size distribution of the pigment in the ink.

(Creation of printed matter)
Organic solvent-based liquid printing inks have excellent adhesion to various substrates and can be used for printing on paper, synthetic paper, thermoplastic resin films, plastic products, steel plates, etc. It is useful as an ink for gravure printing using a gravure printing plate by a resin plate or the like, or for flexographic printing using a flexographic printing plate such as a resin plate.

The film thickness of the printing ink formed by the gravure printing method or the flexographic printing method using the organic solvent-based liquid printing ink of the present invention is, for example, 10 μm or less, preferably 5 μm or less.

(binder resin)
The binder resin for organic solvent-type liquid printing ink is not particularly limited, and general liquid printing inks are generally used without particular limitation, including polyurethane resins, acrylic resins, vinyl chloride-vinyl acetate copolymer resins, and vinyl chloride. - acrylic copolymer resins, chlorinated polypropylene resins, cellulose resins, polyamide resins, ethylene-vinyl acetate copolymer resins, vinyl acetate resins, styrene resins, dammar resins, styrene-maleic acid copolymer resins, polyester resins, Alkyd resin, polyvinyl chloride resin, rosin-based resin, rosin-modified maleic acid resin, terpene resin, phenol-modified terpene resin, ketone resin, cyclized rubber, chlorinated rubber, butyral, polyacetal resin, petroleum resin, and modified resins thereof, etc. can be mentioned. These resins can be used alone or in combination of two or more.

Among the above, polyurethane resins, cellulose resins, polyamide resins, vinyl chloride-vinyl acetate copolymer resins, vinyl chloride-acrylic copolymer resins, ethylene-vinyl acetate copolymer resins, vinyl acetate resins, acrylic resins, styrene resins , styrene-maleic acid copolymer resin, dammar resin, rosin-based resin, rosin-modified maleic acid resin, ketone resin and cyclized rubber.
The content of the binder resin is in the range of 1 to 50% by mass, more preferably 2 to 40% by mass, in terms of the solid content of the water-based liquid printing ink of the present invention.

(Organic solvent)
Organic solvents for organic solvent-type liquid printing inks are not particularly limited, but examples include aromatic hydrocarbon organic solvents such as toluene, xylene, Solvesso #100 and Solvesso #150, hexane, methylcyclohexane, heptane, octane, Examples include aliphatic hydrocarbon-based organic solvents such as decane, and ester-based organic solvents such as methyl acetate, ethyl acetate, isopropyl acetate, normal-propyl acetate, butyl acetate, amyl acetate, ethyl formate, and butyl propionate. Water-miscible organic solvents include alcohols such as methanol, ethanol, propanol, butanol and isopropyl alcohol, ketones such as acetone, methyl ethyl ketone and cyclohaxanone, ethylene glycol (mono, di) methyl ether, and ethylene glycol (mono, di) ethyl. Ether, ethylene glycol monopropyl ether, ethylene glycol monoisopropyl ether, monobutyl ether, diethylene glycol (mono, di) methyl ether, diethylene glycol (mono, di) ethyl ether, diethylene glycol monoisopropyl ether, diethylene glycol monobutyl ether, triethylene glycol (mono, Di)methyl ether, propylene glycol (mono, di)methyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol (mono, di)methyl ether, and other glycol ether organic solvents can be used. These may be used alone or in combination of two or more.

Organic solvent-based liquid printing inks may also contain waxes, chelate cross-linking agents, extender pigments, leveling agents, antifoaming agents, plasticizers, infrared absorbers, ultraviolet absorbers, fragrances, flame retardants, etc. can also

(coloring agent)
The organic solvent-based liquid printing ink uses the modified pigment as a coloring agent, but in addition to this, organic pigments and/or inorganic pigments used in general inks, paints, recording agents, etc. may be used in combination. .
Examples of organic pigments include soluble azo, insoluble azo, azo, phthalocyanine, halogenated phthalocyanine, anthraquinone, anthanthrone, dianthraquinonyl, anthrapyrimidine, perylene, perinone, quinacridone, Examples include thioindigo, dioxazine, isoindolinone, quinophthalone, azomethineazo, flavanthrone, diketopyrrolopyrrole, isoindoline, indanthrone, and carbon black pigments. Also, for example, Carmine 6B, Lake Red C, Permanent Red 2B, Disazo Yellow, Pyrazolone Orange, Carmine FB, Chromophtal Yellow, Chromophtal Red, Phthalocyanine Blue, Phthalocyanine Green, Dioxazine Violet, Quinacridone Magenta, Quinacridone Red, Indance Ron blue, pyrimidine yellow, thioindigo bordeaux, thioindigo magenta, perylene red, perinone orange, isoindolinone yellow, aniline black, diketopyrrolopyrrole red, daylight fluorescent pigments, and the like. Both non-acid-treated pigments and acid-treated pigments can be used.

Inorganic pigments include white inorganic pigments such as titanium oxide, zinc oxide, zinc sulfide, barium sulfate, calcium carbonate, chromium oxide, silica, litbon, antimony white, and gypsum. Among inorganic pigments, the use of titanium oxide is particularly preferred. Titanium oxide exhibits a white color and is preferable from the viewpoints of coloring power, hiding power, chemical resistance and weather resistance. From the viewpoint of printing performance, the titanium oxide is preferably treated with silica and/or alumina.
Examples of non-white inorganic pigments include aluminum particles, mica (mica), bronze powder, chrome vermilion, yellow lead, cadmium yellow, cadmium red, ultramarine blue, Prussian blue, red iron oxide, yellow iron oxide, iron black, and zircon. Although the aluminum is in the form of powder or paste, it is preferable to use it in the form of paste from the viewpoints of handling and safety, and whether to use leafing or non-leafing is appropriately selected from the viewpoint of brightness and density.
The average particle size of the pigment is preferably in the range of 10 to 200 nm, more preferably about 50 to 150 nm.
The amount of the pigment is sufficient to ensure the concentration and coloring strength of the aqueous liquid printing ink, that is, 1 to 60% by mass of the total mass of the ink, and 10 to 90% by mass of the solid content in the ink. It is preferably contained in proportion. Moreover, these pigments can be used individually or in combination of 2 or more types.

(water-based liquid printing ink)
A water-based liquid printing ink is obtained by dispersing a mixture containing the modified pigment used in the present invention, a binder resin, an aqueous medium, a dispersant, an antifoaming agent, etc. described below with a disperser to obtain a pigment dispersion. It can be obtained by adding a resin, an aqueous medium, and, if necessary, an additive such as a leveling agent to the obtained pigment dispersion, and stirring and mixing. As a dispersing machine, bead mill, eiger mill, sand mill, gamma mill, attritor, etc., which are commonly used for the production of gravure and flexographic printing inks, are used. The viscosity is preferably 7 to 25 seconds at 25° C. using Zahn Cup #4 manufactured by Rigosha, more preferably 10 to 20 seconds. The surface tension of the obtained flexographic ink at 25° C. is preferably 25-50 mN/m, more preferably 33-43 mN/m. The lower the surface tension of the ink, the better the wettability of the ink to the substrate such as a film. tends to be easily connected, and tends to cause stains on the printing surface called dot bridges. On the other hand, if the surface tension exceeds 50 mN/m, the wettability of the ink to the base material such as a film is lowered, which tends to cause repelling.

On the other hand, when a water-based liquid printing ink is used as a gravure ink, the viscosity may be 7 to 25 seconds at 25° C. using Zahn Cup #3 manufactured by Rigosha, more preferably 10 to 20 seconds. . The surface tension of the obtained gravure ink at 25° C. is preferably 25 to 50 mN/m, more preferably 33 to 43 mN/m, like the flexo ink. The lower the surface tension of the ink, the better the wettability of the ink to the substrate such as a film. tends to be easily connected, and tends to cause stains on the printing surface called dot bridges. On the other hand, if the surface tension exceeds 50 mN/m, the wettability of the ink to the base material such as a film is lowered, which tends to cause repelling.

(Creation of printed matter)
Water-based liquid printing inks have excellent adhesion to various substrates and can be used for printing on paper, synthetic paper, thermoplastic resin films, plastic products, steel plates, etc. It is useful as an ink for gravure printing using a printing plate or for flexographic printing using a flexographic printing plate such as a resin plate.

The film thickness of the printing ink formed by the gravure printing method or the flexographic printing method using the water-based liquid ink of the present invention is, for example, 10 μm or less, preferably 5 μm or less.

(binder resin)
Binder resins for water-based liquid printing inks are not particularly limited, and include urethane resins, polyvinyl alcohols, polyvinylpyrrolidones, polyacrylic acid, acrylic acid-acrylonitrile copolymers, and acrylic acid that are commonly used for water-based liquid printing inks. Acrylic copolymers such as potassium-acrylonitrile copolymer, acrylic acid ester polymer emulsion, polyester urethane dispersion, vinyl acetate-acrylic acid ester copolymer, acrylic acid-acrylic acid alkyl ester copolymer; Acrylic acid copolymer, styrene-methacrylic acid copolymer, styrene-methacrylic acid-acrylic acid alkyl ester copolymer, styrene-α-methylstyrene-acrylic acid copolymer, styrene-α-methylstyrene-acrylic acid- Styrene-acrylic acid resin such as acrylic acid alkyl ester copolymer; styrene-maleic acid; styrene-maleic anhydride; vinylnaphthalene-acrylic acid copolymer; vinylnaphthalene-maleic acid copolymer; vinyl acetate-ethylene copolymer vinyl acetate-based copolymers such as vinyl acetate-fatty acid vinyl ethylene copolymers, vinyl acetate-maleic acid ester copolymers, vinyl acetate-crotonic acid copolymers, vinyl acetate-acrylic acid copolymers, and these Salt can be used. These binder resins can be used alone or in combination of two or more.

Among them, it is preferable to use an acrylic resin or a urethane resin as the binder resin because they are readily available, and acrylic acid ester polymer emulsions and polyester urethane dispersions are particularly preferable.

The binder resin preferably accounts for 5 to 50% by mass in terms of solid content of the water-based liquid printing ink of the present invention. If it is 5% by mass or more, the strength of the ink coating film does not decrease, and good adhesion to substrates, resistance to water rubbing, etc. can be maintained. Conversely, when the amount is 50% by mass or less, it is possible to suppress a decrease in coloring power, avoid high viscosity, and prevent a decrease in workability. Among them, 5 to 40% by mass is more preferable, and 5 to 20% by mass is most preferable.

(aqueous medium)
Aqueous media for aqueous liquid printing inks include, for example, water, water-miscible organic solvents, and mixtures thereof. Examples of water-miscible organic solvents include alcohol solvents such as methanol, ethanol, n-propanol and isopropanol; ketone solvents such as acetone and methyl ethyl ketone; polyalkylene glycols such as ethylene glycol, diethylene glycol and propylene glycol; alkyl ethers of; and lactam solvents such as N-methyl-2-pyrrolidone. In the present invention, only water may be used, a mixture of water and an organic solvent miscible with water may be used, or only an organic solvent miscible with water may be used. As the aqueous medium, water alone or a mixture of water and an organic solvent miscible with water is preferable, and water alone is particularly preferable, from the viewpoint of safety and environmental load.

The water-based liquid printing ink may also contain the aforementioned colorants, extenders, pigment dispersants, leveling agents, defoamers, plasticizers, infrared absorbers, ultraviolet absorbers, fragrances, flame retardants, and the like. Fatty acid amides such as oleic acid amide, stearic acid amide, and erucic acid amide for imparting friction resistance and slipperiness, among others, and silicon-based, non-silicon-based defoaming agents and pigments for suppressing foaming during printing Various dispersing agents that improve the wettability of the polymer are useful.

EXAMPLES The present invention will be described more specifically with reference to examples. Hereinafter, "parts" and "%" are based on mass.
In addition, the measurement of the weight average molecular weight (in terms of polystyrene) by GPC (gel permeation chromatography) in the present invention was carried out under the following conditions using an HLC8220 system manufactured by Tosoh Corporation.
Separation column: 4 TSKgelGMHHR-N manufactured by Tosoh Corporation are used.
Column temperature: 40°C.
Moving bed: Tetrahydrofuran manufactured by Wako Pure Chemical Industries, Ltd.
Flow rate: 1.0 ml/min.
Sample concentration: 0.4% by mass.
Sample injection volume: 100 microliters.
Detector: differential refractometer.
Viscosity was measured at 25° C. with a B-type viscometer manufactured by Tokimec.

The acid value of wax indicates the number of milligrams of potassium hydroxide required to neutralize the acidic component contained in 1 g of wax solid content.・Calculated from potentiometric titration with ethanol solution.

(Adjustment of nitrocellulose resin solution N)
Industrial nitrocellulose L1/8 (nitrocellulose, solid content 30%, viscosity 1.6 to 2.9% at a solution concentration of 25.0% according to JIS K-6703, manufactured by Taihei Chemicals Co., Ltd.) to 37.5 parts 62.5 parts of a mixture of isopropyl alcohol/ethyl acetate/n-propyl acetate/methylcyclohexane (ratio by weight: 25/25/13/10) was added and thoroughly mixed to prepare a nitrocellulose resin solution N.

(Adjustment of cellulose ester resin solution C1)
To 20 parts of cellulose acetate propionate CAP482-0.5 (manufactured by Eastman Chemical Co.), a mixture of isopropyl alcohol/ethyl acetate/n-propyl acetate/methylcyclohexane (ratio by weight: 25/25/13/10) was added. 80 parts were added and thoroughly mixed to prepare a cellulose ester resin solution C1.

(Adjustment of cellulose ester resin solution C2)
A mixture of isopropyl alcohol/ethyl acetate/n-propyl acetate/methylcyclohexane (25/25/13/10 by weight) was added to 20 parts of cellulose acetate butyronate CAB381-0.5 (manufactured by Eastman Chemical). 80 parts were added and thoroughly mixed to prepare a cellulose ester resin solution C2.

(Preparation of dimer acid-modified polyamide resin solution Pa)
A four-neck flask equipped with a stirrer, a thermometer, a reflux condenser and a nitrogen gas inlet tube was charged with 100 parts of dimer acid (Halidimer 270S; manufactured by Harima Kasei Co., Ltd.), tall oil fatty acid (Hartol FA-1; Harima Kasei Co., Ltd.). Co., Ltd.), 5 parts of sebacic acid, 10 parts of ethylenediamine, 5 parts of hexamethylenediamine, and 0.24 parts of triphenylphosphine were added, and the system was filled with a nitrogen atmosphere. The temperature is slowly raised to 200°C while Subsequently, dehydration condensation is performed at 200° C. for 5 hours while stirring to obtain a dimer acid-modified polyamide resin derived from tall fatty acid having a solid content of 20%, a softening point of 123° C., an amine value of 2, an acid value of 8, and a number average molecular weight of 10,000. A solution Pa was obtained.

(Preparation of polyurethane resin solution Pu)
162.58 parts of Mn 2,000 polyester polyol (manufactured by DIC: POLYLITE OD-X-2044) obtained from adipic acid and neopentyl glycol is placed in a four-necked flask equipped with a stirrer, thermometer, reflux condenser and nitrogen gas inlet tube. And polypropylene glycol (manufactured by Mitsui Chemicals: Actcol D-1000) 40.65 parts, isophorone diisocyanate 66.23 parts, ethyl acetate 50 parts, DICNATE 425 (manufactured by DIC) 0.03 parts were charged, and 75 ° C. under a nitrogen stream. was reacted for 3 hours. Then, 2.17 parts of 2-butyl-2-ethylpropanediol having a number average molecular weight (Mn) of 160.3 was added, and the mixture was further reacted at 75°C for 3 hours. After completion of the reaction, 200 parts of normal propyl acetate was added to dilute the reaction solution. After cooling the reaction solution to 45° C. or lower, 200 parts of isopropyl alcohol was added. The reaction solution was maintained at about 35 to 40°C, 23.53 parts of isophoronediamine dissolved in 100 parts of ethyl acetate was added dropwise, and the mixture was allowed to react at 50°C for 3 hours while stirring. Then, 4.84 parts of cyclohexylamine was added and reacted at 50° C. for 30 minutes while stirring. Finally, 150 parts of ethyl acetate was added to obtain a polyurethane resin solution (Pu) having a nonvolatile content of 30.0%, a Gardner viscosity of V (25° C.) and an Mw of 40,000.

(Adjustment of acrylic resin solution Ac)
A solid acrylic resin (Dianal BR-90, manufactured by Mitsubishi Chemical Corporation) was stirred and dissolved in ethyl acetate to obtain a 30% solution, which was used as an acrylic resin solution Ac.

(Adjustment of vinyl chloride vinyl acetate copolymer resin solution Ev)
A 25% solution of a vinyl chloride-vinyl acetate copolymer resin having a hydroxyl group (resin monomer composition in mass %, vinyl chloride/vinyl acetate/vinyl alcohol = 92/3/5, hydroxyl value (mgKOH) = 64) was made into a 25% solution with ethyl acetate, This was designated as a vinyl chloride-vinyl acetate copolymer resin solution Ev.

<Preparation of photocatalyst>
First, the properties of the titanium oxide raw material (manufactured by Showa Denko Ceramics Co., Ltd.) to be used were measured as follows.

(BET specific surface area)
The BET specific surface area of the titanium oxide raw material was measured using a fully automatic BET specific surface area measuring device "Macsorb, HM model-1208" manufactured by Mountec Co., Ltd.
(Rutile content (rutilization ratio) and crystallinity (full width at half maximum) in titanium oxide raw material)
The content (rutilization ratio) and crystallinity (full width at half maximum) of rutile-type titanium oxide in the titanium oxide raw material were measured by powder X-ray diffractometry.

That is, for the dried titanium oxide raw material, using "X'pertPRO" manufactured by PANalytical as a measuring device, using a copper target, using Cu-Kα1 line, tube voltage 45 kV, tube current 40 mA, measurement range 2θ = 20 X-ray diffraction measurement was performed under the conditions of ~100 deg, a sampling width of 0.0167 deg, and a scanning speed of 3.3 deg/min.

Obtain the peak height (Hr) corresponding to the rutile crystal, the peak height (Hb) corresponding to the brookite crystal, and the peak height (Ha) corresponding to the anatase crystal, and use the following formula to calculate titanium oxide The content of rutile-type titanium oxide (rutilization rate) in the medium was determined.

Rutilization rate (mol%) = {Hr / (Ha + Hb + Hr)} x 100
Also, the content of anatase-type titanium oxide (anatase conversion rate) and the content of brookite-type titanium oxide (brookite conversion rate) in titanium oxide were determined by the following formulas.

Anatase rate (mol%) = {Ha / (Ha + Hb + Hr)} x 100
Brookite conversion rate (mol%) = {Hb/(Ha + Hb + Hr)} x 100
In the X-ray diffraction pattern obtained by the above X-ray diffraction measurement, the strongest diffraction peak corresponding to rutile-type titanium oxide was selected and the full width at half maximum was measured.

(Primary particle size)
The average primary particle diameter (DBET) (nm) is obtained by measuring the specific surface area S (m ² /g) of titanium oxide by the BET 1-point method, and using the following formula
DBET=6000/(S×ρ)
calculated from Here, ρ indicates the density of titanium oxide (g/cm ³ ).

Table 1 shows the measurement results of the titanium oxide raw material used.

(Production example 1)
6 g (100 parts by mass) of titanium oxide raw material (manufactured by Showa Denko Ceramics Co., Ltd.) was suspended in 100 mL of distilled water, and 0.0805 g (0.5 parts by mass in terms of copper) of CuCl ₂ .2H ₂ O (Kanto Chemical Co., Ltd.) was added and stirred for 10 minutes. A 1 mol/L sodium hydroxide (manufactured by Kanto Kagaku Co., Ltd.) aqueous solution was added so that the pH was 10, and the mixture was stirred and mixed for 30 minutes to obtain a slurry. This slurry was filtered, and the obtained powder was washed with pure water, dried at 80° C., and pulverized with a mixer to obtain a sample (photocatalyst).

The resulting sample (photocatalyst) was heated in a hydrofluoric acid solution to completely dissolve, and the extract was quantified by ICP emission spectrometry. As a result, the amount of copper ions was 0.5 parts by mass with respect to 100 parts by mass of titanium oxide. That is, all of the charged copper ions (derived from CuCl ₂ .2H ₂ O) were supported on the titanium oxide surface.

The sample (photocatalyst) obtained in Production Example 1 was analyzed by the following method.

(Content of rutile-type titanium oxide (rutilization rate) and crystallinity (full width at half maximum))
With respect to the sample (photocatalyst) obtained in Production Example 1, the content of rutile-type titanium oxide in titanium oxide (rutilization ratio) and crystallinity (full width at half maximum) were measured by powder X-ray diffractometry.

That is, a powder obtained by grinding a dried photocatalyst with a mortar was used as a sample. For this sample, using "X'pertPRO" manufactured by PANalytical as a measuring device, using a copper target, using Cu-Kα1 wire, tube voltage 45 kV, tube current 40 mA, measurement range 2θ = 20 to 100 deg, sampling width 0 X-ray diffraction measurement was performed under the conditions of 0.0167 deg and a scanning speed of 3.3 deg/min.

Obtain the peak height (Hr) corresponding to the rutile crystal, the peak height (Hb) corresponding to the brookite crystal, and the peak height (Ha) corresponding to the anatase crystal, and use the following formula to calculate titanium oxide The content of rutile-type titanium oxide (rutilization rate) in the medium was determined.

Rutilization rate (mol%) = {Hr / (Ha + Hb + Hr)} x 100
In the X-ray diffraction pattern obtained by the above X-ray diffraction measurement, the strongest diffraction peak corresponding to rutile-type titanium oxide was selected and the full width at half maximum was measured.

(Identification of divalent copper compound)
The bivalent copper compound present in the sample (photocatalyst) obtained in Production Example 1 was identified by X-ray diffraction measurement using the above measuring apparatus and measuring conditions. Table 2 shows the results.

[Examples and Comparative Examples]
According to the formulation shown in Table 3, the binder resin, the photocatalyst, and the organic solvent were uniformly mixed in a bead mill to obtain a coating agent composition.

<Preparation of laminate having coating layer>
[Create gravure coating]
The viscosity of the obtained coating agents of Examples and Comparative Examples was adjusted to 16 seconds (25 ° C.) with Zahn Cup #3 (manufactured by Rigosha) using any of the mixed solvents A to D listed in the table. Using a gravure proofing machine equipped with a 35 μm gravure plate, Examples 1 to 4 were applied to biaxially oriented polypropylene films (OPP films), Examples 5 to 9 were applied to polyethylene terephthalate films (PET films), and Examples 10 to 10 were applied to coated balls. The laminate printed on paper was allowed to stand for one day to obtain a laminate for evaluation.

[Create flexo coating]
The viscosity of the obtained coating agents of Examples and Comparative Examples was adjusted to 20 seconds (25 ° C.) with Zahn Cup #3 (manufactured by Rigosha) with any of the mixed solvents A to D listed in Table 3, and 120 lines. A laminate printed on coated cardboard and PET film by a flexo proofing machine equipped with a /cm anilox roll was allowed to stand for one day to obtain a laminate for evaluation.

In Table 3, the numbers are parts.

Adhesion, abrasion resistance, and antiviral properties were evaluated using the obtained laminate (substrate having a coating layer).

[Evaluation Item 1: Adhesion]
A cellophane tape (12 mm width, manufactured by Nichiban) was attached to the printed surface, and the external appearance of the printed film was visually evaluated according to the following five grades when the tape was quickly peeled off.
When printing on coated cardboard 5: Paper peeled, no peeling between coating agent layers 4: Paper peeling, peeling between coating agent layers less than 25 3: Paper peeling, peeling between coating agent layers 25-75%
2: The paper peeled off, and the peeling between the layers of the coating agent was 75% or more. 25-50%
2: Coating agent peeling is 50-75%
1: Coating agent peeling is 75-100%

[Evaluation item 2: Abrasion resistance]
The abrasion resistance of the produced printed matter was evaluated using a robust Gakushin tester. A copy paper was used as the friction element, and the state of the surface of the printed material after 100 reciprocations under a load of 500 g was visually evaluated in the following five stages.

5: No change in printed surface 4: Few scratches on printed surface 3: Many scratches on printed surface 2: Part of coating agent peeled off, base material visible 1: Coating agent peeled off, base material is only

(Evaluation item 3 Antiviral evaluation)
An anti-phage virus test (see JIS R1756) was performed on the evaluation printed matter obtained above.
1) Light irradiation conditions were such that the light from a white fluorescent lamp was cut with an N113 filter to cut ultraviolet rays, and the illuminance was set to 1000 lux.
2) After dropping 100 μL of Qβ phage solution of known concentration on a 5 cm×5 cm print for evaluation, it was sandwiched between glass plates of 5 cm×5 cm.
3) The sample irradiated with light for 2 hours was recovered with SCDLP solution, and the appropriately diluted sample was infected with E. coli, spread on an agar medium, and evaluated by counting the number of colonies after culturing. Antiviral activity was evaluated by the degree of inactivation of Qβ phage, and inactivation degrees of -2 to -5 were evaluated as having antiviral activity.
The degree of inactivation is -1 for 90%, -2 for 99%, and -3 for 99.9%, indicating high antiviral activity. The limit of detection is -5 degrees of inactivation.

Tables 4 to 6 show the evaluation results of laminates using the compositions of Examples and Comparative Examples.
In addition, a blank represents unblending.

Raw material names in the table are as follows.
Chlorinated polyolefin solution Ep: Superchron 360T (manufactured by Nippon Paper Industries Co., Ltd.)
Hydrophobic silica: Silysia 350D (manufactured by Fuji Silysia Chemical Co., Ltd.)
Wax 1: Mitsui High Wax 220MP (manufactured by Mitsui Chemicals, Inc.)
Wax 2: Amide AP-1 (manufactured by Mitsubishi Chemical Corporation)
Plasticizer 1: Eposizer W-100EL (manufactured by DIC Corporation)
Plasticizer 2: ATBC
Chelating agent: ORGATICS TC-100 (manufactured by Matsumoto Fine Chemicals Co., Ltd.)
Polyester: Barnock D-50-75 (manufactured by DIC Corporation)

From the above results, the coating agent of the present invention can impart good antiviral properties to paper substrates or plastic substrates by a simple method, that is, by simply coating these substrates. It has become clear that flexible substrates, packaging materials, containers and the like can be provided. In addition, the coating agent of the present invention can exhibit sufficient antiviral properties while maintaining adhesion and abrasion resistance.

Claims (4)

Contains a binder resin (A), a photocatalyst (B), and an organic solvent,
The photocatalyst (B) contains titanium oxide containing crystalline rutile-type titanium oxide and a divalent copper compound,
The crystalline rutile-type titanium oxide has a full width at half maximum of 0.65 degrees or less of the strongest diffraction peak corresponding to rutile-type titanium oxide in an X-ray diffraction pattern in which the diffraction line intensity is plotted against the diffraction angle 2θ by Cu-Kα rays. is titanium oxide of
A photocatalyst in which the content of the crystalline rutile-type titanium oxide in the titanium oxide is 50 mol% or more and the content of the anatase-type titanium oxide is less than 50 mol%,
Containing 0.5 to 80% by mass of the photocatalyst (B) based on the total solid content of the coating agent,
The binder resin (A) is a combination selected from urethane-based resin/vinyl chloride-based resin, urethane-based resin/ cellulose -based resin, polyamide-based resin/ cellulose -based resin, and acrylic resin/ cellulose -based resin. A coating agent for paper substrates or plastic substrates. A paper base material or a plastic base material obtained by coating a paper base material or a film with the coating agent according to claim 1 . 3. The paper or plastic substrate according to claim 2, wherein said paper or plastic substrate further comprises a printing ink layer. A container or packaging material using the paper base material or plastic base material according to claim 2 or 3.