JP2019119823A - Liquid printing ink composition for surface printing, and printed matter - Google Patents

Abstract

To provide a gravure printing ink composition for surface printing excellent especially in heat resistance, blocking resistance to vinyl chloride and dot reproductivity without a highlight point corresponding to a small dot even in high speed printing in addition to excellent various ink coated film properties including substrate adhesiveness to a substrate film, and having printability hardly generating printing contamination of a non-printing part without a pattern, and a printed matter by printing the gravure printing ink composition for surface printing.SOLUTION: There is provided a gravure printing ink composition for surface printing containing a polyurethane resin (P1) having a structure derived from a polymer diol compound using phthalic acid as a reaction raw material, a chelate crosslinking agent (A), a pigment (B), and an organic solvent (C).SELECTED DRAWING: None

Description

  The present invention relates to a liquid printing ink composition for surface printing which can be used as a liquid ink for soft packaging.

  BACKGROUND ART Liquid inks such as gravure inks and flexo inks are widely used for the purpose of imparting cosmetic properties and functionality to a substrate of a soft packaging film. When a gravure or flexographic printed material is used as a soft packaging material particularly for food and hygiene products among packaging materials, the product packaging should be a package that touches the contents to prevent contact with the contents. The front side printing which does not print on the back side corresponding to the material side but carries out design printing only on the outside of the packaging material is performed.

  The liquid printing ink composition for surface printing is required to have the film strength and various resistance because the ink film printed on the front side of the film substrate is directly rubbed by external force or is in contact with other substances. Ru.

  That is, adhesion to various film substrates, blocking resistance that does not adhere to each other when the printed surface and the printed surface of the front or the printed surface of the front and the back of the film are in close contact, on a vinyl chloride table cloth When placing the product, there is no resistance to polyvinyl chloride blocking, no alcohol adhesion when alcohol adheres to the printing surface, alcohol resistance, no organic solvent or oil adheres, or food in the packing stage. It is desirable to have oil resistance such that the pattern does not melt or peel off when oil content adheres, and heat resistance such that the ink is not peeled off by the heat seal bar at the time of bag making.

  And while maintaining the above-mentioned performance, the highlight point corresponding to the small dot is not distorted even in high-speed printing, the dot reproducibility is excellent, and the print contamination of the non-printed part having no pattern is less likely to occur. It is desirable to have printability as well.

  For example, invention of a gravure ink composition using a urethane resin and a cellulose derivative (for example, Patent Documents 1 and 2), a surface-printing gravure ink composition containing a polyurethane resin, a vinyl chloride vinyl acetate copolymer, rosin, and a chelate Inventions (for example, Patent Documents 3 and 4), invention of a surface printing gravure ink composition using an ester-based resin and an ester-based dispersing agent (for example, Patent Document 5) have been made, but all have various tolerances. It can not be said that printability is compatible, and, among others, it is not easy to simultaneously achieve both heat resistance, blocking resistance to vinyl chloride and printability.

JP, 2007-246822, A JP 2002-294128 A JP 2012-012597 A JP, 2013-256551, A JP, 2017-039896, A

  The subject of the present invention is high heat resistance, high resistance to blocking against vinyl chloride and high dot speed in high speed printing, in addition to excellent various ink film properties including adhesion to the base film. A liquid printing ink composition for surface printing and a liquid printing ink composition for surface printing having print aptitude which is excellent in halftone dot reproducibility without light spots and less likely to generate printing stains on a non-printing part having no pattern Relating to printed matter produced by printing

  The liquid printing ink composition for surface printing of the present invention is found to be effective for solving the problems by containing a polyurethane resin having a structure derived from a specific high molecular weight diol compound, a chelate crosslinking agent, a pigment and an organic solvent. The

  That is, the present invention comprises a polyurethane resin (P1) having a structure derived from a polymeric diol compound using phthalic acid as a reaction raw material, a chelate crosslinking agent (A), a pigment (B), and an organic solvent (C). The present invention relates to a liquid printing ink composition for surface printing characterized by

  Furthermore, the present invention relates to a liquid printing ink composition for surface printing comprising a cellulose resin (D) and / or a vinyl chloride / vinyl acetate copolymer resin (E).

  Furthermore, the present invention is a polyester resin wherein the high molecular weight diol compound is a condensation product of phthalic acid, a polyvalent carboxylic acid compound and a polyhydric alcohol, and the high molecular weight diol compound has a number average molecular weight (Mn) of 400 to 4000. The present invention relates to a certain surface printing liquid printing ink composition.

  Furthermore, the present invention relates to a liquid printing ink composition for surface printing comprising fatty acid amide (F) in an amount of 0.1 to 3.0% by mass of the total amount of the composition.

  Furthermore, according to the present invention, the organic solvent (C) does not contain an aromatic hydrocarbon organic solvent and contains an alcohol having a specific evaporation rate of 100 or less when the evaporation rate of butyl acetate is 100. The present invention relates to a liquid printing ink composition for printing.

  Furthermore, the present invention relates to a printed matter obtained by printing the liquid printing ink composition for surface printing.

  According to the present invention, highlight points corresponding to fine dots especially in heat resistance, blocking resistance to vinyl chloride and high speed printing, in addition to excellent various ink coating film properties including substrate adhesion to a substrate film. Printable liquid printing ink composition for surface printing and liquid printing ink composition for surface printing that combines print aptitude that is excellent in halftone dot reproducibility and less likely to cause printing stains on non-printed areas without pattern. Can provide the

  The present invention will be described in detail. The term "ink" used in the following description refers to "liquid printing ink". Moreover, "part" shows all "mass parts" and "%" shows all "mass%."

  The liquid ink composition for surface printing of the present invention comprises a polyurethane resin (P1) having a structure derived from a polymeric diol compound using phthalic acid as a reaction raw material, a chelate crosslinking agent (A), a pigment (B), and an organic solvent And (C).

(Polyurethane resin (P1))
The polyurethane resin (P1) used in the present invention has a structure derived from a polymer diol compound using phthalic acid as a reaction raw material, and specifically, at least phthalic acid, a polyvalent carboxylic acid compound and a polyhydric alcohol as components. A polyurethane resin (P1) having a structure derived from a polyester polyol (hereinafter sometimes referred to as polyester polyol (PE1)) consisting of a polycondensate of a compound, and at least phthalic acid, a polyvalent carboxylic acid compound and a polyvalent compound as components. It is obtained by reacting a polyester polyol composed of a polycondensate of an alcohol compound with a polyisocyanate.

(Polyester polyol (PE1))
Examples of phthalic acid used for the polyester polyol (PE1) include phthalic anhydride, terephthalic acid and isophthalic acid. In the present invention, terephthalic acid or isophthalic acid is preferable.

The polyester polyol (PE1) can be made of a known polyvalent carboxylic acid compound or polyhydric alcohol compound as a raw material without particular limitation except that the phthalic acid is used as an essential raw material. Examples of polyvalent carboxylic acids include adipic acid, phthalic acid, maleic acid, fumaric acid, succinic acid, oxalic acid, malonic acid, glutaric acid, pimelic acid, speric acid, azelaic acid, sebacic acid, trimellitic acid and pyromellitic acid. There may be mentioned polyvalent carboxylic acids such as acids or their anhydrides.
The use ratio of phthalic acid in the polyvalent carboxylic acid compound is preferably in the range of 5 to 100% by weight, and more preferably in the range of 20 to 90% by weight.

  Further, as the polyhydric alcohol compound, for example, various known polyols generally used for the production of the polyurethane resin described later can be used, among which ethylene glycol, 1,2-propanediol, 1,3-propanediol, and the like can be used. Propanediol, 2-methyl-1,3-propanediol, 2-ethyl-2-butyl-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-hexane Triol, 1,2,4-butane triol, sorbitol, low-molecular polyols, saturated or unsaturated, such as pentaerythritol (2) is preferred. These polyols may be used alone or in combination of two or more.

  The polyester polyol (PE1) preferably has a number average molecular weight (hereinafter sometimes referred to as Mn) of 400 to 4,000. If the number average molecular weight is 400 or more and 4000 or less, heat resistance tends to be particularly excellent.

The polyurethane resin (P1) of the present invention is not particularly limited except that the polyester polyol (PE1) is essential as a polyhydric alcohol compound, and polycondensed with a polyvalent carboxylic acid compound and a polyhydric alcohol compound by a known method You can get it.
The amount of the polyester polyol (PE1) used is preferably 10 to 95 parts by mass with respect to 100 parts by mass of the polyhydric alcohol compound.

  As a polyhydric alcohol compound used as needed for the polyurethane resin (P1) used by the liquid printing ink composition for surface printing of this invention, various well-known polyols generally used for manufacture of a polyurethane resin are used. It may be used alone or in combination of two or more.

As said polyol, various well-known polyols generally used for manufacture of a polyurethane resin can be used, and 1 type, or 2 or more types may be used together.
For example, polyethylene glycol which is a polymer or copolymer of methylene oxide, ethylene oxide, tetrahydrofuran or the like, polyether polyol such as polypropylene glycol, polyoxytetramethylene glycol or the like (1);
Ethylene glycol, 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3-propanediol, 2-ethyl-2-butyl-1,3-propanediol, 1,3-butanediol, 1 2,4-butanediol, neopentyl glycol, pentanediol, 3-methyl-1,5-pentanediol, hexanediol, octanediol, 1,4-butynediol, 1,4-butylenediol, diethylene glycol, triethylene glycol, Saturated or unsaturated low molecular weight polyols such as dipropylene glycol, glycerin, trimethylolpropane, trimethylolethane, 1,2,6-hexanetriol, 1,2,4-butanetriol, sorbitol, pentaethlytol 2);

These low molecular weight polyols (2) and adipic acid, maleic acid, fumaric acid, succinic acid, oxalic acid, malonic acid, glutaric acid, pimelic acid, speric acid, azelaic acid, sebacic acid, trimellitic acid, pyromellitic acid Polyester polyols (3) obtained by dehydration condensation or polymerization of polyvalent carboxylic acids such as acids or their anhydrides;
Polyester polyols (4) obtained by ring-opening polymerization of cyclic ester compounds, for example, lactones such as polycaprolactone, polyvalerolactone, poly (β-methyl-γ-valerolactone);
Polycarbonate polyols (5) obtained by the reaction of the low molecular weight polyols (2) and the like with, for example, dimethyl carbonate, diphenyl carbonate, ethylene carbonate, phosgene and the like;
Polybutadiene glycols (6);
Glycols obtained by adding ethylene oxide or propylene oxide to bisphenol A (7);
Obtained by copolymerizing, for example, acrylic acid, methacrylic acid or an ester thereof with one or more of hydroxyethyl, hydroxypropyl acrylate, acrylic hydroxybutyl, etc., or the corresponding methacrylic acid derivative thereof in one molecule. Acrylic polyol (8) and the like.

Among the polyester polyols (3), a high molecular weight diol obtained from a diol (glycols) and a dibasic acid is a low molecular weight compound having three or more hydroxyl groups up to 5 mol% of the diol. It can be substituted with polyols (2).
Among them, it is preferable to use polyester polyols (hereinafter, polyester polyols which do not use phthalic acid may be referred to as “polyester polyols (PE 2)”) in combination. The polyester polyol preferably has a number average molecular weight of 400 to 3,000. Moreover, it is preferable that the usage-amount is said polyester polyol (PE1): polyester polyol (PE2) = 100: 0-5:95.

As a diisocyanate compound used for the polyurethane resin (P1) in the liquid printing ink composition for surface printing of the present invention, various well-known aromatic diisocyanates, aliphatic diisocyanates and alicyclic groups generally used in the production of polyurethane resins Diisocyanate etc. are mentioned. For example, 1,5-naphthyl diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-dibenzyl isocyanate, dialkyldiphenylmethane diisocyanate, tetraalkyldiphenylmethane diisocyanate, 1,3- Phenylene diisocyanate, 1,4-phenylene diisocyanate, tolylene diisocyanate, butane-1,4-diisocyanate, hexamethylene diisocyanate, isopropylene diisocyanate, methylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, cyclohexane-1 , 4-diisocyanate, xylylene diisocyanate, isophorone diisocyanate, dime Diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, methylcyclohexane diisocyanate, norbornane diisocyanate, m-tetramethyl xylylene diisocyanate, 4,4-diphenylmethane diisocyanate, tolylene diisocyanate And bis-chloromethyl-diphenylmethane-diisocyanate, 2,6-diisocyanate-benzyl chloride, and dimeric isocyanate obtained by converting carboxyl group of dimer acid to isocyanate group. These diisocyanate compounds can be used alone or in combination of two or more.
Among them, isophorone diisocyanate is preferred.

  The chain extender used for the polyurethane resin (P1) in the liquid printing ink composition for surface printing of the present invention includes ethylene diamine, propylene diamine, hexamethylene diamine, diethylene triamine, triethylene tetramine, isophorone diamine, dicyclohexyl methane-4, Other than 4'-diamine and the like, 2-hydroxyethylethylenediamine, 2-hydroxyethylpropyldiamine, 2-hydroxyethylpropylenediamine, di-2-hydroxyethylethylenediamine, di-2-hydroxyethylenediamine, di-2-hydroxyethylpropylene Diamines, 2-hydroxypyrrole ethylenediamine, di-2-hydroxypyrrole ethylenediamine, di-2-hydroxypropylethylenediamine, etc. Amines that can also be used. These chain extenders can be used alone or in combination of two or more.

  Moreover, a monovalent active hydrogen compound can also be used as an end capping agent for the purpose of terminating the reaction. Examples of such a compound include dialkylamines such as di-n-butylamine and alcohols such as ethanol and isopropyl alcohol. Furthermore, especially when it is desired to introduce a carboxyl group into the polyurethane resin, amino acids such as glycine and L-alanine can be used as the reaction terminator. These end capping agents can be used alone or in combination of two or more.

  The polyurethane resin (P1) in the liquid printing ink composition for surface printing of the present invention has, for example, an isocyanate group consisting of phthalic acid, a polyester polyol consisting of a condensation product of a polycarboxylic acid compound and a polyalcohol compound, a combination polyol and a diisocyanate compound. The reaction is carried out in an excess proportion to obtain a prepolymer of terminal isocyanate groups, and the resulting prepolymer is treated with an appropriate solvent, that is, an ester such as ethyl acetate, propyl acetate or butyl acetate which is usually used as a solvent for gravure ink. Solvents; Ketone solvents such as acetone, methyl ethyl ketone and methyl isobutyl ketone; Alcohol solvents such as methanol, ethanol, isopropyl alcohol and n-butanol; Toluene, xylene, methyl cyclohexane and ethyl cyclohexene A two-step method of reacting with a chain extender and / or an end capping agent mixed with a hydrocarbon solvent such as a polyester polyol, or a polyester polyol comprising a condensation product of a phthalic acid, a polycarboxylic acid compound and a polyalcohol compound, and combined use The polyol, the diisocyanate compound, the chain extender and / or the end capping agent are produced in one step by reacting in one of the above-mentioned suitable solvents. Among these methods, in order to obtain a uniform polyurethane resin, the two-stage method is preferable. Furthermore, in recent years, it is more preferable not to use aromatic solvents such as toluene and xylene and ketone solvents from the viewpoint of working environment.

  The weight average molecular weight of the polyurethane resin (P1) thus obtained is preferably in the range of 15,000 to 100,000, and more preferably in the range of 15,000 to 80,000. When the weight average molecular weight of the polyurethane resin is less than 15,000, the blocking resistance of the resulting composition of the ink, the strength and heat resistance of the print film, and the like tend to be lowered, and when it exceeds 100,000. The viscosity of the resulting ink composition tends to be high, and the gloss of the printed film tends to be low.

  The content of the polyurethane resin (P1) in the ink for use in the liquid printing ink composition for surface printing of the present invention is 4% by mass with respect to the total mass of the ink from the viewpoint of sufficient adhesion of the ink to the printing material % Or more, preferably 25% by mass or less, and more preferably 6 to 15% by mass from the viewpoint of appropriate ink viscosity and working efficiency at the time of ink production and printing.

  The weight average molecular weight of the polyurethane resin used in the liquid printing ink composition for surface printing of the present invention is preferably in the range of 15,000 to 100,000. When the number average molecular weight of the polyurethane resin is less than 15,000, the resulting ink tends to have low blocking resistance, laminate strength and chemical resistance, etc., and when it exceeds 100,000, the obtained ink The viscosity of the ink tends to be high, and a predetermined printing density can not be obtained.

  The content of the polyurethane resin in the liquid ink composition for surface printing of the present invention is 0.1 to 8.0% by mass, 0.3 to 5.0% by mass, in terms of solid content. Is more preferred.

  In the present invention, as the polyurethane resin, only the polyurethane resin (P1) having a structure derived from the high molecular weight diol compound using the phthalic acid as a reaction raw material may be used, or a plurality of polyurethane resins may be used in combination. . In that case, as a polyurethane resin (P1) having a structure derived from a high molecular weight diol compound using phthalic acid as a reaction raw material, the compounding ratio of phthalic acid or a polyvalent carboxylic acid compound or polyhydric alcohol compound used other than phthalic acid A plurality of polyurethane resins having different types, amounts used, or molecular weights may be used in combination, or the polyurethane resin (P1) having a structure derived from a high molecular weight diol compound using the phthalic acid as a reaction raw material and the phthalic acid You may use together with the polyurethane resin which is not used as a raw material.

  When using together the polyurethane resin which does not use phthalic acid as a reaction raw material (hereinafter, a polyurethane resin which does not use phthalic acid as a reaction raw material may be referred to as "urethane resin (P2)"), the number average of urethane resin (P2) The polyurethane resin (P2) having a polyester polyol structure having a molecular weight of 400 to 3,000 is preferable, and the mass ratio of the polyurethane resin (P1) to the polyurethane resin (P2) is preferably 100: 0 to 5:95.

(Chelate crosslinker)
In the liquid printing ink composition for surface printing of the present invention, it is essential to contain the chelate crosslinking agent (A). Among them, chelate-type metal organic compounds for the purpose of improving cohesion are preferred. As the metal chelate compound, organic titanium type, organic zirconium type and organic aluminum type can be used. If a chelate type metal organic compound is used, the crosslinking reaction is completed without heating, but hydrolysis at room temperature is unlikely to occur, and a stable crosslinking reaction is obtained, particularly when an amine is present in the molecule. The effect is great.

  As described above, since the liquid printing ink composition for surface printing is printed on the front side of the packaging material, the ink film is exposed to the outside and is in direct contact with various substances. Therefore, in addition to the adhesion of the substrate to the film, tough film physical properties such as heat resistance and oil resistance are required. Particularly in recent years, there has been a demand for a surface printing ink that is highly heat resistant to heat sealing at the time of film making and oil resistant to oil contained in food, but since the ink of the present invention contains a chelate crosslinking agent, Film properties can be obtained.

The titanium chelate has a Ti—O—C bond in one molecule, and has the role of strengthening intermolecular or intramolecular cross-linking of the resin by having this alkoxy group. Examples of titanium chelates include titanium alkoxides and titanium acylates. Examples of the titanium alkoxide include tetraisopropyl titanate, tetranormal butyl titanate, butyl titanate dimer, tetra (2-ethylhexyl) titanate, tetramethyl titanate, tetrastearyl titanate, triethanolamine titanate, titanium acetyl acetate, titanium ethyl acetoacetate And titanium lactate, octylene glycol titanate, titanium tetraacetyl acetate, titanium phosphate compounds and the like. Among organic titanium-based compounds, titanium phosphate compounds and titanium acetyl acetate are preferred. As a commercial item, titanium TAA chelating agent (made by BORICA): titanium acetylacetonate CAS: 17927-27-9 etc. are mentioned.
The content of the chelate crosslinking agent is preferably 0.1 to 5.0% by mass, and more preferably 0.5 to 3.0% by mass of the total amount of the liquid printing ink composition for surface printing.

(Pigment (B))
The pigment (B) used in the liquid printing ink composition for surface printing of the present invention may be either a color pigment or a white pigment. If a white pigment is added, it can also be used as a white ink corresponding to the background of a picture, for example, in the case of surface printing liquid printing as an example. If these pigments are not added, they can also be used as overcoat varnish applications.

  Examples of the color pigment used in the liquid printing ink composition for surface printing of the present invention include organic pigments and dyes used in general inks, paints, recording agents and the like. As the organic pigment, azo type, phthalocyanine type, anthraquinone type, perylene type, perinone type, perinone type, quinacridone type, thioindigo type, dioxazine type, isoindolinone type, quinophthalone type, azomethine azo type, diketopyrrolopyrrole type, isoindoline type etc. Pigments are listed.

As a color index name,
C. I. Pigment Yellow 1, 3, 12, 13, 14, 17, 42, 74, 83;
C. I. Pigment Orange 16;
C. I. Pigment Red 5, 22, 38, 48: 1, 48: 2, 48: 4, 49: 1, 53: 1, 57: 1, 63: 1, 81, 101;
C. I. Pigment Violet 19, 23;
C. I. Pigment Blue 23, 15: 1, 15: 3, 15: 4, 17: 1, 18, 27, 29
C. I. Pigment Green 7, 36, 58, 59;
C. I. Pigment Black 7;
C. I. Pigment White 4, 6, 18 and the like.

  C.I. I. Pigment Blue 15: 3 (copper phthalocyanine), yellow ink, C.I. I. Pigment Yellow 83, C.I. I. It is preferable to use Pigment Red 57: 1. It is preferable to use carbon black for the black ink, aluminum for the gold and silver inks, and mica for the pearl ink from the viewpoint of cost and coloring power. Aluminum is in the form of powder or paste, but is preferably used in the form of paste in terms of handleability and safety, and whether leafing or non-leafing is used is appropriately selected in terms of brightness and density.

Moreover, as a white pigment used for the liquid printing ink composition for surface printings of this invention, a titanium oxide, zinc sulfide, lead white, zinc flower, lithobon, antimony white, basic lead sulfate, basic silicic acid is mentioned, for example. Lead, barium sulfate, calcium carbonate, gypsum, silica and the like can be mentioned.
The average particle diameter of the pigment is preferably in the range of 10 to 200 nm, more preferably about 50 to 150 nm.
The pigment is preferably added in an amount of 1 to 20% by mass based on the total amount of the ink in order to obtain sufficient image density and light resistance of the printed image.

(Organic solvent (C))
The organic solvent (C) used in the liquid printing ink composition for surface printing of the present invention is not particularly limited, and examples thereof include aromatic hydrocarbon organic solvents such as toluene, xylene, Solvesso # 100, Solvesso # 150, etc. Aliphatic hydrocarbon-based organic solvents such as hexane, methylcyclohexane, heptane, octane and decane; esters such as methyl acetate, ethyl acetate, isopropyl acetate, normal propyl acetate, butyl acetate, amyl acetate, ethyl formate and butyl propionate Various organic solvents can be mentioned. Further, as water miscible organic solvents, 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, 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 Over mono propyl ether, propylene glycol monobutyl ether, dipropylene glycol (mono, di) include various organic solvents glycol ether such as methyl ether. These can be used alone or as a mixture of two or more.

Among them, it is preferable to contain an alcohol which does not contain an aromatic hydrocarbon organic solvent and has a specific evaporation rate of 100 or less when the evaporation rate of butyl acetate is 100.
As such alcohol, for example, 1-propyl alcohol (CAS No. 71-23-8, evaporation rate 94), isobutyl alcohol (CAS No. 78-83-1, evaporation rate 64), 1-butanol (CAS No. 71- 36-3, evaporation rate 47), 2-butanol (CAS No. 78-92-2, evaporation rate 89), 4-hydroxy-4-methyl-2-pentanone (CAS No. 123-42-2, evaporation rate 15) Ethylene glycol monomethyl ether (CAS No. 109-86-4, evaporation rate 53), ethylene glycol monoethyl ether (CAS No. 110-80-5, evaporation rate 38), ethylene glycol mono-normal butyl ether (CAS No. 111-76) -2, evaporation rate 8), ethylene glycol mono-tertiary butyl ether (CAS No. 7580-85-0, evaporation rate 19), 3-methoxy-3-methylbutanol (CAS No. 56539-66-3, evaporation rate 7), 1-methoxy-2-propanol (CAS No. 107-98-) 2, evaporation rate 71), 1-ethoxy-2-propanol (CAS No. 1569-02-4, evaporation rate 34), propylene glycol monopropyl ether (CAS No. 1569-01-3, evaporation rate 22).

By containing an alcohol having a specific evaporation rate of 100 or less, it is possible to maintain highlight transferability with a dot area of 10% or less and highlight improvement.
The mechanism has the following two points. First of all,
1) After the ink is transferred to the film, about half of the ink remains in the cells of the gravure plate.
2) The remaining ink volatilizes the solvent contained until it comes in contact with the ink in the ink pan again, and becomes semi-dry. Further, since the solvent evaporates from the solvent having a high evaporation rate, the solvent having a low evaporation rate remains in the ink pan.
3) At this time, if the solvent having high resin solubility remains, the semi-dried ink will be redissolved when it comes in contact with the ink again, and the ink will be prevented from solidifying in the cell.
The mechanism as described above tends to be difficult to function in general-purpose alcohols whose specific evaporation rate exceeds 100 when the evaporation rate of butyl acetate is 100, because the evaporation rate is high.
Second, the alcohol having a specific evaporation rate of 100 or less when the evaporation rate of butyl acetate is 100 has a low percentage of hydroxyl groups (alcohol groups) in one molecule of alcohol, so the solubility of the polyurethane resin is It tends to raise.

From the viewpoints of both the process hygiene and the harmfulness of the packaging material, 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 / normal propyl propyl acetate / methylcyclohexane is more preferable from the viewpoint of solubility in polyurethane resin and cotton nitrate. Moreover, if it is less than 10% by mass of the total amount of the composition for dry adjustment, glycol ethers can also be added.

(Cellulose resin (D) and vinyl chloride vinyl acetate copolymer resin (E))
Furthermore, the liquid ink composition for surface printing of the present invention may further contain a cellulose resin (D) and / or a vinyl chloride vinyl acetate copolymer resin (E).

The cellulose-based resin (D) used in the liquid printing ink composition for surface printing of the present invention is suitable because high dispersibility of the pigment is obtained, and the heat resistance and oil resistance of the printing ink film are improved. .
The cellulose resin (D) preferably has a nitrogen content of 10 to 13% by mass and an average degree of polymerization of 30 to 500, and more preferably a nitrogen content of 10 to 13% by mass, and an average degree of polymerization of 45 to 290 . The addition amount of the cellulose resin (D) is preferably 0.05 to 10% by mass with respect to the ink solid content. More preferably, it is 0.1 to 3% by mass.

  The vinyl chloride / vinyl acetate copolymer resin (E) having a hydroxyl group has a hydroxyl value of 50 to 200 mg KOH / g, and the content ratio of the vinyl chloride component in the copolymer resin is 80 to 95 mass%. Things are preferred.

  The vinyl chloride vinyl acetate copolymer resin (E) which has a hydroxyl group used for the liquid printing ink composition for surface printing of this invention can be obtained by two types of methods. One is obtained by copolymerizing vinyl chloride monomer, vinyl acetate monomer and vinyl alcohol in appropriate proportions. The other is obtained by partially saponifying vinyl acetate after copolymerization of vinyl chloride and vinyl acetate. In the vinyl chloride / vinyl acetate copolymer resin having a hydroxyl group, the properties of the resin film and the resin dissolution behavior are determined by the monomer ratio of vinyl chloride, vinyl acetate and vinyl alcohol. That is, vinyl chloride imparts toughness and hardness to the resin film, vinyl acetate imparts adhesiveness and flexibility, and vinyl alcohol imparts good solubility in polar solvents.

(Fatty acid amide (F))
The liquid printing ink composition for surface printing of the present invention is preferable because it can improve heat resistance, oil resistance, and resistance to polyvinyl chloride by adding fatty acid amide (F) and using it together with a polyurethane resin.
It is preferable to add the said fatty acid amide (F) in the range of 0.1-3.0 mass% of the liquid printing ink composition whole quantity for surface printings, and it is more preferable if it is 0.5-2.0 mass%. When the content is less than 0.1% by mass, the resistance to polyvinyl chloride blocking may decrease. When the content is 3.0% by mass or more, the oil resistance tends to decrease.

  The fatty acid amide (F) used in the liquid ink composition of the present invention may be a very general polycondensate of a polycarboxylic acid such as a polymerized fatty acid or various vegetable fatty acids and a polyamine.

The above-mentioned polymerized fatty acid is obtained by the polymerization of an unsaturated fatty acid having 16 to 22 carbon atoms or an ester thereof, and includes monobasic fatty acid, dimerized polymerized fatty acid, trimerized polymerized fatty acid and the like. Specifically, dimer acid, hydrogenated dimer acid and the like can be mentioned.
Moreover, as various vegetable fatty acids, the said polymeric fatty acid is a thing obtained by the superposition | polymerization of the C16-C22 unsaturated fatty acid or its ester, and a monobasic fatty acid, dimerization polymerization fatty acid, trimerization superposition | polymerization It contains fatty acid and so on. Specifically, tall oil fatty acid, palm oil fatty acid, coconut oil fatty acid, soybean oil fatty acid, cacao fatty acid, rice bran fatty acid, and mixed fatty acids of these natural fats and oils may be used as reaction raw materials.

In addition, as the polyamine, aliphatic diamines such as ethylenediamine, propylenediamine, hexamethylenediamine, etc., aliphatic polyamines such as diethylenetriamine and triethylenetetramine, etc., and alicyclic diamines such as cyclohexylenediamine and isophoronediamine, etc. And aromatic diamines such as phenylenediamine and diaminodiphenylmethane.
Also, as primary and secondary monoamines, mono- and di-alkylamines such as butylamine, octylamine and diethylamine, and mono- and di-alkanolamines such as monoethanolamine, monopropanolamine, diethanolamine and dipropanolamine are listed. be able to.
In addition, when a polyamide resin having a hydroxyl group in the molecule formed of an alkanolamine as the primary or secondary monoamine component, the reactivity with the chelating agent tends to be further increased, and the hydroxyl value in that case is 0.5 to 0.5. The range of 10 is preferable.

  Specifically, lauric acid amide (weight average molecular weight 199.3 CAS No. 1120-16-7) or the like is particularly preferable in order to improve the resistance to polyvinyl chloride blocking to the soft vinyl chloride sheet used for the table cloth.

Moreover, the polyamide resin of a number average molecular weight 500-10,000 can also be used preferably. The number average molecular weight is more preferably 1,000 to 10,000.
When the number average molecular weight of the polyamide resin is less than 500, the resistance to blocking of vinyl chloride tends to decrease, and when it is 10,000 or more, the ink stability and the oil resistance tend to decrease.
From the viewpoint of high-speed printability, the content is preferably 20% by mass or less based on the total amount of the polyurethane resin and the cellulose-based resin, and is more preferably 10% by mass or less as long as resistance to polyvinyl chloride can be maintained.

  The liquid printing ink composition for surface printing of the present invention may be used together with a resin, an extender, a pigment dispersant, a leveling agent, an antifoamer, waxes, a plasticizer, an infrared absorber, an ultraviolet absorber and an aroma according to necessity. Agent, flame retardant, etc. can also be included. Among them, paraffin wax for imparting abrasion resistance, slip property, etc., polyethylene wax, carnauba wax, oleic acid amide, stearic acid amide, fatty acid amides such as erucic acid amide, and for suppressing foaming upon printing Useful are silicone type, non-silicon type antifoaming agents, and various dispersants for improving the wetting of pigments.

(Method of producing ink composition)
The liquid ink composition for surface printing of the present invention can be produced, for example, from polyurethane resins, chelate crosslinking agents, pigments, fatty acid amides, organic solvents, and, if necessary, antistatic agents, antiblocking agents, plasticizers, etc. Additives, dispersants for improving ink fluidity and dispersibility, surfactants, or resins compatible with polyurethane resin are used together in a range in which thickening and gelation do not occur with time, ball mill, This is done by kneading using a conventional printing ink production apparatus such as an attritor or sand mill. In particular, the addition of the antistatic agent is effective for suppressing electrostatic troubles during printing, which are called so-called spikes, which are easily generated when using ester solvents and ketone solvents.

(Printed matter)
The printed material of the present invention can be obtained by printing a liquid printing ink composition for surface printing on a plastic film or the like by a known printing method such as gravure printing or flexographic printing. The ink composition of the present invention is preferably used for surface printing.

The plastic film that can be used corresponding to the liquid printing ink composition for surface printing of the present invention is not particularly limited. For example, polyamide resins such as nylon 6, nylon 66, nylon 46, polyethylene phthalate (PET), polyethylene na Polyester resins such as phthalate, polytrimethylene terephthalate, polytrimethylene naphthalate, polybutylene terephthalate, polybutylene naphthalate, polyhydroxycarboxylic acids such as polylactic acid, poly (ethylene succinate), poly (butylene succinate), etc. Films made of thermoplastic resins such as biodegradable resins represented by aliphatic polyester resins, polyolefin resins such as polypropylene (PP) and polyethylene, polyimide resins, polyarylate resins, or mixtures thereof These laminates can be mentioned. Among these, polyester, polyamide, polyethylene, films of polypropylene can be preferably used. These base films may be unstretched films or stretched films, and the production method is not limited. Further, the thickness of the base film is not particularly limited, but usually, it may be in the range of 1 to 500 μm.
Moreover, if corona discharge treatment is carried out to the printing side of a substrate film, substrate adhesiveness can be further improved and it is preferable. In addition, silica, alumina or the like may be vapor deposited.

  Hereinafter, the present invention will be specifically described using examples. In addition, "part" in an Example represents a mass part, and "%" represents mass%.

(Molecular weight measurement of polyurethane resin)
The measurement of the number average molecular weight and the weight average molecular weight (in terms of polystyrene) of the polyurethane resin by GPC (gel permeation chromatography) in the present invention was performed under the following conditions using an HLC 8220 system manufactured by Tosoh Corporation.
Separation column: Four Tosoh Co., Ltd. product TSKgelGMH _HR- N is 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.

  Moreover, the Gardner viscosity in 25 degreeC was confirmed with the Gardner viscometer.

Synthesis Example 1: Synthesis of Polyurethane Resin Solution (Pu1)
Adipic acid, terephthalic acid (adipic acid / terephthalic acid = 1/1 molar ratio) and 3-methyl-1,5-pentanediol in a 4-neck flask equipped with a stirrer, thermometer, reflux condenser and nitrogen gas inlet tube Obtain 229.18 parts of polyester polyol (hereinafter referred to as Mn) 2,000 polyester polyol (made by Kuraray; Kuraray P-2011) and 50.92 parts of isophorone diisocyanate to be obtained, and react at 90 ° C. for 5 hours under nitrogen stream I did. After completion of the reaction, 200 parts of normal propyl acetate was added to dilute the reaction solution. The reaction solution was cooled to 45 ° C. or less, and 200 parts of isopropyl alcohol was added. The reaction solution was maintained at about 35 to 40 ° C., 17.17 parts of isophorone diamine was dissolved in 150 parts of ethyl acetate, added dropwise, and allowed to react at 50 ° C. for 3 hours under a stirring frame. Thereafter, 2.73 parts of cyclohexylamine were added and reacted at 50 ° C. for 30 minutes under stirring frame. Finally, 150 parts of ethyl acetate was added to obtain a polyurethane resin solution (Pu1) having a nonvolatile content of 30.0%, a Gardner viscosity V (25 ° C.), and a mass average molecular weight (hereinafter referred to as Mw) 43,000.

Synthesis Example 2: Synthesis of Polyurethane Resin Solution (Pu2)
Adipic acid, isophthalic acid (adipic acid / isophthalic acid = 1/1 molar ratio) and 3-methyl-1,5-pentanediol in a 4-neck flask equipped with a stirrer, thermometer, reflux condenser and nitrogen gas inlet tube Charge 75.54 parts of polyester polyol (made by Kuraray; Kuraray polyol P-1012), 151.08 parts of polypropylene glycol (made by Mitsui Chemicals, Inc .: Actocol D-1000), and 55.95 parts of isophorone diisocyanate to be obtained. The reaction was carried out at 90 ° C. for 5 hours under a nitrogen stream. After completion of the reaction, 200 parts of normal propyl acetate was added to dilute the reaction solution. The reaction solution was cooled to 45 ° C. or less, and 200 parts of isopropyl alcohol was added. The reaction solution was maintained at about 35 to 40 ° C., and 23.53 parts of isophorone diamine was dissolved in 150 parts of ethyl acetate and added dropwise, and allowed to react at 50 ° C. for 3 hours under a stirring frame. Thereafter, 4.84 parts of cyclohexylamine were added and reacted at 50 ° C. for 30 minutes under stirring frame. Finally, 150 parts of ethyl acetate was added to obtain a polyurethane resin solution (2) having a nonvolatile content of 30.0%, Gardner viscosity U (25 ° C.) and Mw of 54,000.

Synthesis Example 3 Synthesis of Polyurethane Resin Solution (Pu 3)
Adipic acid, terephthalic acid (adipic acid / terephthalic acid = 1/1 molar ratio) and 3-methyl-1,5-pentanediol in a 4-neck flask equipped with a stirrer, thermometer, reflux condenser and nitrogen gas inlet tube 170.04 parts of the obtained polyester polyol of Mn 2,000 (Kuraray; manufactured by Kuraray Polyol P-2011), 45.55 parts of a polyethylene glycol-polypropylene glycol block copolymer (manufactured by NOF Corporation; Pronon # 102), and isophorone diisocyanate 59. 37 parts were charged and allowed to react at 90 ° C. for 5 hours under nitrogen flow. After completion of the reaction, 200 parts of normal propyl acetate was added to dilute the reaction solution. The reaction solution was cooled to 45 ° C. or less, and 200 parts of isopropyl alcohol was added. The reaction solution was maintained at about 35 to 40 ° C., 21.10 parts of isophorone diamine was dissolved in 150 parts of ethyl acetate, added dropwise, and reacted at 50 ° C. for 3 hours under a stirring frame. Thereafter, 3.94 parts of di-n-butylamine were added and reacted at 50 ° C. for 30 minutes under stirring. Finally, 150 parts of ethyl acetate was added to obtain a polyurethane resin solution (Pu3) having a nonvolatile content of 30.0%, a Gardner viscosity W (25 ° C.), and a Mw of 40,000.

Synthesis Example 4 Synthesis of Polyurethane Resin Solution (Pu 4)
In a tetrafluoro flask equipped with a stirrer, a thermometer, a reflux condenser and a nitrogen gas inlet tube, a polyester polyol of Mn 2,000 obtained from adipic acid and 3-methyl-1,5-pentanediol (manufactured by Kuraray; Kurare polyol P- 2010) 222.37 parts and 54.35 parts of isophorone diisocyanate were charged, and reacted at 90 ° C. for 5 hours under a nitrogen stream. After completion of the reaction, 200 parts of normal propyl acetate was added to dilute the reaction solution. The reaction solution was cooled to 45 ° C. or less, and 200 parts of isopropyl alcohol was added. The reaction solution was kept at about 35 to 40 ° C., 19.31 parts of isophorone diamine was dissolved in 150 parts of ethyl acetate and added dropwise, and allowed to react at 50 ° C. for 3 hours under a stirring frame. Thereafter, 3.97 parts of cyclohexylamine were 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 4) having a nonvolatile content of 30.0%, a Gardner viscosity W (25 ° C.), and a mass average molecular weight (hereinafter referred to as Mw) 44,000.

Synthesis Example 5 Synthesis of Polyurethane Resin Solution (Pu 5)
A polyester polyol (product of DIC; Polylite OD-X-2640) 204 obtained from adipic acid and 1,6-hexanediol in a square flask equipped with a stirrer, thermometer, reflux condenser and nitrogen gas inlet tube .84 parts, 25.61 parts of polypropylene glycol (made by Mitsui Chemicals; Actocal D-1000), and 51.21 parts of isophorone diisocyanate were charged, and reacted at 90 ° C for 5 hours under a nitrogen stream. After completion of the reaction, 200 parts of normal propyl acetate was added to dilute the reaction solution. The reaction solution was cooled to 45 ° C. or less, and 200 parts of isopropyl alcohol was added. The reaction solution was maintained at about 35 to 40 ° C., 15.70 parts of isophorone diamine was dissolved in 150 parts of ethyl acetate and added dropwise, and allowed to react at 50 ° C. for 3 hours under a stirring frame. Thereafter, 2.65 parts of di-n-butylamine were added and reacted at 50 ° C. for 30 minutes under stirring. Finally, 150 parts of ethyl acetate was added to obtain a polyurethane resin solution (Pu5) having a nonvolatile content of 30.0%, a Gardner viscosity V (25 ° C.) and a Mw of 43,000.
Each raw material used by the said polyurethane-resin solution (Pu1)-(Pu5) synthesis | combination is shown in Table 1 in a mass part. The numbers in Table 1 are parts by mass.

Polyol Acetol: Polyethers polyol consisting of adipic acid / terephthalic acid / 3-methyl-1,5-pentanediol = 1/1/2 (mass ratio). Number average molecular weight Mn: 2000 (Kuraray Kuraray polyol P2011)
Polyoltes polyol consisting of polyol B: adipic acid / isophthalic acid / 3-methyl-1,5-pentanediol = 1/1/2 (mass ratio). Number average molecular weight Mn: 1000 (Kuraray Kuraray polyol P1012)
-Polyol C: Polypropylene glycol Number average molecular weight Mn: 2000 (Mitsui Chemical D-2000)
-Polyol D: Polyethylene glycol-Polypropylene glycol-Block copolymer Number average molecular weight Mn: 1250 (Nippon oil pronon # 102)
Polyethers polyol consisting of polyol E: adipic acid / 3-methyl-1,5-pentanediol = 1/1 (mass ratio). Number average molecular weight Mn: 2000 (Kuraray Kuraray polyol P 2010)
Polyethers polyol consisting of polyol F: adipic acid / 1,6-hexanediol = 1/1 (mass ratio). Number average molecular weight Mn: 2000 (Polylight OD-X-2640 manufactured by DIC)
Polyol G: Polypropylene glycol Number average molecular weight Mn: 1000 (D-1000 manufactured by Mitsui Chemicals)

(Preparation of nitrocellulose solution N)
To 37.5 parts of industrial-use nitrification cotton H1 / 2 (nitrocellulose, 30% solids, viscosity 9.0 to 14.9% product at 25.0% solution concentration according to JIS K-6703, manufactured by Taihei Chemical Co., Ltd.) Then, 62.5 parts of a mixed solution of isopropyl alcohol / ethyl acetate / normal propyl acetate / methylcyclohexane (ratio by weight 25/25/13/10) was added and thoroughly mixed to prepare nitrocellulose solution N.
(Preparation of vinyl chloride vinyl acetate copolymer resin solution V)
Acetic acid / vinyl acetate copolymer resin having a hydroxyl group to be used in combination with a polyurethane resin (resin monomer composition is% by mass vinyl chloride / vinyl acetate / vinyl alcohol = 92/3/5, hydroxyl value (mg KOH) = 64) A 15% solution was prepared with n-propyl, and this was used as a salt and vinyl acetate resin solution (V).

(Preparation of Rosin Resin Solution R)
50 parts of rosin resin (trade name: NEOCITE F-896, manufactured by Konan Kasei Co., Ltd.) was dissolved in 50 parts of isopropyl alcohol to obtain a rosin resin solution having a solid content of 50%.

[Examples 1 to 6, Comparative Examples 1 to 5: Preparation Method of Ink]
A mixture obtained by mixing polyurethane resin solutions Pu1 to Pu5 shown in Table 1 at the compounding ratio shown in Table 2 and Table 3 is kneaded using Mighty mill (made by Inoue Seisakusho Co., Ltd.), and Examples 1 to 6 and The chewing ink described in Comparative Examples 1 to 5 was prepared, and the following evaluation was carried out for each.

  In addition, as a metal chelate crosslinking agent, titanium TAA chelating agent (Titanium acetylacetonate, CAS number 17927-27-9) by BORICA was used.

[Base material adhesion]
Apply the rouge ink described in Table 2 and Table 3 to a biaxially stretched polypropylene film (FOR made by Futamura Chemical Co., Ltd., thickness: 20 μm) which has been subjected to corona discharge treatment on one side with a bar coater # 10 and leave it for 24 hours I made a printed matter.
Subsequently, a cellophane tape (manufactured by Nichiban Co., Ltd.) was attached to the printed surface, and the tape was quickly peeled off, and the state of the printed surface was visually evaluated. Evaluation 4 or more is a practical range.
(Evaluation criteria)
5: The printed film does not peel at all from the film.
4: Less than 20% peels from the film as the area ratio of the printed film.
3: 20% or more and less than 50% of the film ratio of the printed film
Peel from.
2: 50% or more and less than 80% of the film ratio of the printed film
Peel from.
1: 80% or more peels from a film as an area ratio of a printing surface.

[Blocking resistance]
The amber ink described in Tables 2 and 3 is diluted with a mixed organic solvent consisting of ethyl acetate / normal propyl acetate / cyclohexane in the same ratio as used in the preparation of the ink, and it becomes 16 seconds with Zahn cup No. 3 manufactured by Rigosha Co., Ltd. As diluted. A biaxially stretched polypropylene film (Futamura Chemical Co., Ltd.), one side of which was subjected to corona discharge treatment using an MD-type gravure printer (manufactured by Fuji Machine Co., Ltd.) attached with a laser gravure plate having a plate depth of 25 μm. Printing was performed on a treated surface of 20 μm in thickness.
Next, the obtained printed matter is cut into a size of 4 cm × 4 cm, this ink-coated surface and the non-treated surface of the same film cut into the same size are overlapped, and the weight is 10 kg / cm. The load ^c was applied and tightened, and after standing for 24 hours in an atmosphere of 40 ° C. and humidity 80%, the printed surface and the plastic film were peeled off by hand, and the blocking resistance was evaluated from the degree of ink peeling. Evaluation 4 or more is a practical range.
(Evaluation criteria)
5: There is no peeling of the printed film and no peeling resistance is felt at all.
4: There is no peeling of the printed film, but some peeling resistance is not felt.
3: The printed film was slightly peeled off, and peeling resistance was felt.
2: The printed film peels off, and peeling resistance is felt strong.
1: The printing film almost peels off, and the peeling resistance is felt strongly.

[PVC resistance]
A load of 0.5 kg / cm ² is obtained by superposing a commercially available soft vinyl chloride sheet (made by Doit Co., Ltd.) cut into the same size and size as each printed material used in the above-mentioned evaluation of blocking resistance and the printing surface After standing for 24 hours under an atmosphere of 50 ° C. and humidity of 80%, the printed surface and the polyvinyl chloride sheet were peeled off, and the polyvinyl chloride blocking resistance was evaluated from the degree of peeling of the ink.
Evaluation 4 or more is a practical range.
(Evaluation criteria)
5: The printed film did not peel at all.
4: The area of the printed film peeled from the film is 20% or more and less than 50%.
3: The area of the printed film peeled from the film is 50% or more and less than 75%.
2: The area where the printed film peeled from the film is 75% or more and less than 90%.
1: 90% or more of the area of the printed film peeled from the film.

Alcohol resistance
The printed surface of each print was rubbed 100 times with a 200 g load of ethanol impregnated cloth using a Gakushin-type friction tester, and alcohol suitability was evaluated from changes in the printed surface.
Evaluation 4 or more is a practical range.
(Evaluation criteria)
5: There is no change in the printing surface and the cloth.
4: There is no change in the printing surface, but the patch is colored.
3: streaky scratches are observed on the printing surface.
2: Thick streaky scratches are observed on the printing surface.
1: There are surface scratches on the printed surface.

〔Heat-resistant〕
Apply the rouge ink described in Table 2 and Table 3 to a biaxially stretched polypropylene film (FOR made by Futamura Chemical Co., Ltd., thickness: 20 μm) which has been subjected to corona discharge treatment on one side with a bar coater # 10 and leave it for 24 hours Printed matter was produced.
Then, using a heat seal tester equipped with a hot plate with a thermal gradient of 80 to 200 ° C on each printing surface on this printing surface, the printing surface and aluminum foil, and the printing surface and printing surface 2.0 kg / cm ^It was pressed for 1 second at a pressure of ² . The heat resistance was evaluated from the lowest temperature at which the ink on the printed surface transferred to the aluminum foil.
Evaluation 4 or more is a practical range.
(Evaluation criteria)
5: One over 180 ° C.
4: More than 160 ° C. and less than 180 ° C.
3: More than 140 ° C. and less than 160 ° C.
2: More than 120 ° C and less than 140 ° C.
1: Less than 120 ° C.

〔Oil resistance〕
The printed surface of each printed material was rubbed 100 times with a 200 g load cloth with a food salad oil: butter impregnated at 1: 1 using a Gakushin type friction resistance tester, and the oil resistance was evaluated from the change in the printed surface did. Evaluation 4 or more is a practical range.
(Evaluation criteria)
5: There is no change in the printing surface and the cloth.
4: There is no change in the printing surface, but the patch is colored.
3: streaky scratches are observed on the printing surface.
2: Thick streaky scratches are observed on the printing surface.
1: There are surface scratches on the printed surface.

[Printability test: cast-off test]
Isopropyl alcohol: normal propyl alcohol: ethyl acetate: normal propyl acetate: cyclohexane = (mass ratio 6 parts: 5 parts: 20 parts) in the same ratio as when the black ink described in Table 2 and Table 3 is used for ink preparation It diluted with the mixed organic solvent which consists of 15 parts: 10 parts), and it diluted so that it might become 16 seconds by remote company Zahn cup No3. A biaxially stretched polypropylene film (Futamura Chemical Co., Ltd.), one side of which was subjected to corona discharge treatment using an MD-type gravure printer (manufactured by Fuji Machine Co., Ltd.) attached with a laser gravure plate having a plate depth of 25 μm. Printing was performed on a treated surface of 20 μm in thickness.
In the castellation test, the ratio of area of castellation in highlight printed area (less than 10% of halftone dot area) at the printing speed of 200m / min at circumference 600mmφ of the gravure plate and the degree of contamination of nonprinted area were visually evaluated . Evaluation 4 or more is a practical range.
(Evaluation criteria)
5: There is no scratch and no stain on the non-printed part.
4: A slight amount of blur is observed or a slight amount of stain is observed on the non-printed portion.
3: A slight amount of blur is observed, and a little stain is observed on the non-printed portion.
2: Spots are observed, and stains are observed on the non-printed part.
1: A lot of blur is seen, and a lot of dirt is seen also in the non-printed part.

  Table 2 shows the composition of each twill ink of the example, and the evaluation results, and Table 3 shows the composition of each twill ink of the comparative example and the evaluation results.

Metal chelate crosslinker: titanium TAA chelating agent (manufactured by Borica): titanium acetylacetonate CAS: 17927-27-9

  From the above results, the printed matter using the liquid printing ink composition for surface printing of the present invention, in addition to excellent various ink coating film properties, particularly heat resistance, blocking resistance to vinyl chloride and high speed printing also in the small mesh As a result, the highlight point corresponding to the point is not blurred and the dot reproducibility is excellent, and the result is a combination of a print suitability which hardly causes the print spot of the non-printed portion and the print spot of the non-printed part.

  The liquid printing ink composition for surface printing of the present invention can be widely developed as various liquid surface printing printed matter for industrial products such as food packaging, sanitary, cosmetic, electronic parts and the like.

Claims (6)

  A table characterized by containing a polyurethane resin (P1) having a structure derived from a high molecular weight diol compound which uses phthalic acid as a reaction raw material, a chelate crosslinking agent (A), a pigment (B) and an organic solvent (C). Liquid printing ink composition for printing.   The liquid printing ink composition for surface printing according to claim 1, further comprising a cellulose resin (D) and / or a vinyl chloride / vinyl acetate copolymer resin (E).   The surface printing according to claim 1 or 2, wherein the high molecular weight diol compound is a polyester polyol comprising a polycondensation product of phthalic acid, a polyhydric carboxylic acid compound and a polyhydric alcohol compound, and the number average molecular weight is 400 to 4000. Liquid printing ink composition.   The liquid printing ink composition for surface printing according to any one of claims 1 to 3, further comprising 0.1 to 3.0% by mass of fatty acid amide (F) based on the total amount of the composition.   The organic solvent (C) does not contain an aromatic hydrocarbon organic solvent and contains an alcohol having a specific evaporation rate of 100 or less when the evaporation rate of butyl acetate is 100. A surface-printing liquid printing ink composition as described in 1 or 2.   The printed matter formed by printing the liquid printing ink composition for front printings as described in any one of Claims 1-5.