JP6604408B2 - Organic solvent gravure ink and printed matter - Google Patents

Description

  The present invention relates to an organic solvent-based gravure ink and a printed matter thereof.

When various plastic substrates are used for packaging materials, printing using printing ink is usually performed for decoration or surface protection of the substrate. The printed substrate is then subjected to a slitting process, and finally becomes a package for food packaging, cosmetic packaging, or any other application.

In many cases, a rotary printing method, that is, a flexographic or gravure printing method is employed for printing on a film substrate. In particular, the plate used for gravure printing is intaglio at the parts such as letters and patterns, so that the ink is immersed in this plate to the extent that ink enters this cell, and the surface is scraped off with a doctor blade while rotating the plate. The gravure ink is printed onto the substrate, and this is done in an interlocked manner. The gravure printing method is suitable for mass production because high-definition printing and high-speed printing are possible. However, improvement of the working environment in printing has been promoted, and non-toluene solvent inks that do not contain an aromatic solvent such as toluene are preferred. On the other hand, food manufacturers and converters are demanding high quality for printing inks due to diversification of packaging and advancement of packaging technology.

The characteristics required of gravure ink in the field of surface printing on film bases are that the printed layer is formed on the outermost surface of the packaging bag, so the physical properties of the printed layer are important in addition to the printability of the ink itself. It becomes. In particular, compatibility at a high level of adhesion to a substrate and scratch resistance is required. Generally, a gravure ink for surface printing is known as a polyolefin base material such as a polypropylene base material, and as a special base material, an antifogging base material is known. The base material varies in polarity, hydrophilicity, hardness, stretched base material and unstretched base material for each type, so it is difficult to obtain adhesion and film properties uniformly on all base materials. It was difficult to maintain both scratch resistance and adhesion to the substrate at a high level.

Therefore, Patent Document 1 discloses a printing ink using a polyamide resin and a cellulose resin as a binder. However, an ink containing a polyamide resin as a main binder has a brittle ink film, so that it is caused by friction with a guide roll of a printing machine. There was a problem that the ink transferred and the appearance of the printed matter was impaired. Therefore, as disclosed in Patent Document 2, a polyurethane-based ink suitable for high-speed printing has been proposed. Furthermore, in a polyurethane-based gravure ink improved in high-speed printing and anti-blocking property, it is exemplified that a chelating agent and an amide wax component are used. (Patent Documents 3, 4, and 5). Patent Document 6 exemplifies gravure ink for paper having excellent dot reproducibility, adhesion and odor. However, a higher level of printing performance and physical properties are required, and a material satisfying printability and ink film physical properties has not yet been invented.

JP-A-9-296143 JP 2012-012597 A JP 2013-127038 A Japanese Patent Laying-Open No. 2015-205993 JP, 2006-043600, A JP 2014-058653 A

  It is an object of the present invention to provide an organic solvent-based gravure ink that can achieve both scratch resistance and adhesiveness even in substrates having different surface treatments and whether or not the substrate is subjected to stretching. And

As a result of intensive studies, the present inventors have found that the above problems can be solved by using the gravure ink described below, and have reached the present invention.
That is, the present invention
The present invention relates to an organic solvent-based gravure ink that satisfies the following (1), (2) and (3) .
(1) hardness at 25 ° C. as defined in JISK2207 of hydrocarbon wax (penetration) is a 0.5 to 12, 0.1 to 2.5 mass hydrocarbon wax in gravure ink amount %contains.
(2) The weight average molecular weight of the chlorinated polyolefin resin is 5,000 to 100,000, containing 0.1 to 2.5% by weight in the gravure ink amount.
(3) The binder resin contains a polyamide resin and at least one resin selected from the group consisting of a vinyl chloride-vinyl acetate copolymer resin, a cellulose resin, and a rosin resin.

The present invention also relates to the organic solvent-based gravure ink for surface printing.

Further, in the present invention, the binder resin contains a polyamide resin and a cellulose resin, and the cellulose resin contains a nitrocellulose resin having a nitrogen content of 10.5 to 12.5. The present invention relates to a solvent-based gravure ink.
Further, in the present invention, the softening point of the polyamide resin is 80 to 140 ° C., and the weight average molecular weight of the polyamide resin is 2,000 to 50,000. Related to system gravure ink.
Moreover, this invention relates to the organic-solvent gravure ink in any one of Claims 1-4 in which a polyamide resin contains 50 mass% or more of structures derived from a dimer acid or a polymeric fatty acid in a polyamide resin .

The present invention further relates to the organic solvent-based gravure ink containing a metal chelate.

Moreover, this invention relates to the printed matter which has a printing layer which consists of said organic solvent type gravure ink on a base material.

According to the present invention, it is possible to provide an organic solvent-based gravure ink that can achieve both scratch resistance and adhesiveness even in substrates having different surface treatments and whether or not stretched, and has excellent printability. did it.

  Embodiments of the present invention will be described in detail below, but the description of the constituent elements described below is an example (representative example) of an embodiment of the present invention, and the present invention does not exceed the gist thereof. The content is not limited.

Hereinafter, the organic solvent-based gravure ink of the present invention may be simply abbreviated as “gravure ink” or “ink”, but is synonymous. A layer on which an organic solvent-based gravure ink is printed may be described as “printing layer”, “ink layer”, or “ink coating”, but they are synonymous.

In this specification, “surface printing” refers to a printing method in which a printed pattern or a pattern can be confirmed when viewed from the ink layer side when printed on a plastic substrate. In addition, when it is set as a packaging bag, the outer surface of a bag becomes an ink layer.

One embodiment of the present invention contains a pigment, a binder resin, a hydrocarbon wax, and a chlorinated polyolefin resin, and is an organic solvent-based gravure ink that satisfies the following (1) and (2).
(1) The hardness (penetration) of the hydrocarbon wax at 25 ° C. defined by JIS K 2207 is 0.5 to 12, and the hydrocarbon wax is 0.1 to 2.5 in the total amount of gravure ink. Contains by mass%.
(2) The weight average molecular weight of chlorinated polyolefin resin is 5,000-100,000, and it contains 0.1-2.5 mass% in gravure ink total amount.

The present inventors contain 0.1 to 2.5% by mass of a hydrocarbon wax having a hardness (penetration) in JIS K 2207 of 0.5 to 12 in 100% by mass (total amount) of gravure ink. In addition, by containing 0.1 to 2.5% by mass of a chlorinated polyolefin resin having a weight average molecular weight of 5,000 to 100,000, it is possible to provide scratch resistance and adhesiveness even for substrates having different properties. I found out that they can be compatible. It has also been found that printability is good by a combination of a hydrocarbon wax and a chlorinated polyolefin.

<Binder resin>
The binder resin refers to the binder resin in the gravure ink of the present invention, and is preferably a thermoplastic resin that is soluble in an organic solvent. The binder resin preferably uses a resin having a glass transition temperature of −60 ° C. or higher and lower than 40 ° C. and a resin having a glass transition temperature of 40 ° C. or higher and 200 ° C. or lower. More preferably, a resin having a glass transition temperature of −50 ° C. to 0 ° C. and a resin having a glass transition temperature of 50 ° C. to 190 ° C. are used in combination. In the present specification, the glass transition temperature is a value measured by a differential scanning calorimeter (DSC).

Examples of binder resins include, but are not limited to, polyurethane resins, cellulose resins, polyamide resins, vinyl chloride-vinyl acetate copolymer resins, vinyl chloride-acrylic copolymer resins, rosin resins, ethylene -Vinyl acetate copolymer resin, vinyl acetate resin, acrylic resin, styrene resin, dammar resin, styrene-maleic acid copolymer resin, polyester resin, alkyd resin, terpene resin, phenol-modified terpene resin, ketone resin, cyclized rubber, Examples thereof include chlorinated rubber, butyral, polyacetal resin, petroleum resin, and modified resins thereof. These resins can be used alone or in admixture of two or more. The binder resin does not include a chlorinated polyolefin resin.

Among these, it is preferable to contain a polyurethane resin and / or a polyamide resin. The total amount of the binder resin is preferably 30 to 95% by mass of the polyurethane resin and / or the polyamide resin. This is because the adhesiveness to the base material is improved. The binder resin preferably further contains at least one resin selected from the group consisting of cellulose resins, vinyl chloride-vinyl acetate copolymer resins, and rosin resins. This is because the blocking resistance is improved.

The binder resin preferably contains at least two kinds of resins. Preferably, it is any combination selected from polyurethane resin / vinyl chloride-vinyl acetate copolymer resin, polyurethane resin / cellulose resin, polyamide resin / cellulose resin, and 2 types of the above combinations in 100% by mass of binder resin It is preferable to contain 70-100 mass% of resin in total, More preferably, it is 90-100 mass%.
Further, the polyurethane resin / vinyl chloride-vinyl acetate copolymer resin, the polyurethane resin / cellulose resin, and the polyamide resin / cellulose resin preferably have a mass ratio of 95/5 to 30/70, respectively. More preferably, it is 90 / 10-50 / 50 by mass ratio. When this blending ratio and combination are used, the blocking resistance and adhesiveness of the printed layer are improved by using a hydrocarbon wax described later in combination.

Further, it contains vinyl chloride-acrylic copolymer resin, ethylene-vinyl acetate copolymer resin, vinyl acetate resin, acrylic resin, styrene resin, styrene-maleic acid copolymer resin, dammar resin, ketone resin, and cyclized rubber. Although it is preferable, it is not limited to these.

<Polyurethane resin>
The polyurethane resin preferably has a weight average molecular weight of 10,000 to 100,000, and preferably has a glass transition temperature of 0 ° C. or lower. It is still more preferably −60 ° C. to 0 ° C., and further preferably −40 to −5 ° C. This is because the affinity with the hydrocarbon wax and the chlorinated polyolefin resin is improved.
The polyurethane resin preferably has an amine value and / or a hydroxyl value, and the amine value is preferably 0.5 to 30 mgKOH / g, more preferably 1 to 20 mgKOH / g. Moreover, it is preferable that a hydroxyl value is 0.5-30 mgKOH / g, More preferably, it is 1-20 mgKOH / g. The adhesiveness to a base material improves that it is the said range.

The polyurethane resin preferably contains a structural unit derived from polyether polyol and / or polyester polyol, and the total content is preferably 5 to 80% by mass in 100% by mass of polyurethane resin solid content, more Preferably it is 10-60 mass%, More preferably, it is 10-50 mass%.

The polyurethane resin is not particularly limited and is appropriately produced by a known method. A polyurethane resin made of a polyol and a polyisocyanate, or a polyurethane resin obtained by reacting a urethane prepolymer of a terminal isocyanate made of a polyol and a polyisocyanate with an amine chain extender is preferred. As a manufacturing method, the method of Unexamined-Japanese-Patent No. 2013-256551 etc. are mentioned, for example.

Examples of the polyol include polyester polyol, polyether polyol, polycaprolactone polyol, polycarbonate polyol, polyolefin polyol, castor oil polyol, hydrogenated castor oil polyol, dimer diol, and hydrogenated dimer diol. Polyether polyol and / or polyester polyol are preferable.

Examples of the polyether polyol include polypropylene glycol, polyethylene glycol, polytetramethylene glycol, and polytrimethylene glycol. The number average molecular weight is preferably 200 to 5,000. The number average molecular weight is calculated from the hydroxyl value with the terminal being a hydroxyl group, and is obtained from (Equation 1).
(Formula 1) Number average molecular weight of polyol = 1000 × 56.1 × Hydroxyl number / Hydroxyl value

Examples of the polyester polyol include a condensate obtained by an esterification reaction of a dibasic acid and a diol. Dibasic acids include adipic acid, phthalic anhydride, isophthalic acid, terephthalic acid, maleic acid, fumaric acid, succinic acid, oxalic acid, malonic acid, pimelic acid, azelaic acid, sebacic acid, suberic acid, glutaric acid, 1 4-cyclohexyl dicarboxylic acid, dimer acid, hydrogenated dimer acid and the like. Examples of the diol include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 1,6-hexanediol, and 1,8-octanediol. 1,9-nonanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, 2-methyl-1,3-propanediol, 3,3,5-trimethylpentanediol, 2,4-diethyl- 1,5-pentanediol, 1,12-octadecanediol, 1,2-alkanediol, 1,3-alkanediol, 1-monoglyceride, 2-monoglyceride, 1-monoglycerin ether, 2-monoglycerin ether, dimer diol , Hydrogenated dimer diol, etc. It is below.

The diol is preferably a diol having a branched structure. The branched structure means a diol having an alkyl side chain in which at least one hydrogen atom of an alkylene group contained in the diol is substituted with an alkyl group, and includes propylene glycol, 1,3-butanediol, 2-methyl-1 , 3-propanediol, neopentyl glycol, 1,4-pentanediol, 3-methyl-1,5-pentanediol, 2,5-hexanediol, 2-methyl-1,4-pentanediol, 2,4- Diethyl-1,5-pentanediol, 2-butyl-2-ethyl-1,3-propanediol, 2-methyl-1,8-octanediol, 2,2,4-trimethyl-1,3-pentanediol, And 2,2,4-trimethyl-1,6-hexanediol and the like. These are particularly preferable because they improve printability, printing effect, and blocking resistance.
These polyester polyols can be used alone or in admixture of two or more. The dibasic acid is particularly preferably sebacic acid or adipic acid. Also, a polyol having 3 or more hydroxyl groups and a polyvalent carboxylic acid having 3 or more carboxyl groups can be used in combination.

The number average molecular weight of the polyester polyol is preferably 200 to 5,000. The number average molecular weight can be determined by the above (Formula 1).

Examples of the polyisocyanate include various known aromatic diisocyanates, aliphatic diisocyanates, and alicyclic diisocyanates that are generally used in the production of polyurethane resins.
As the aromatic diisocyanate, 4,4′-diphenylmethane diisocyanate (MDI), 4,4′-dibenzyl isocyanate, 1,3-phenylene diisocyanate, tolylene diisocyanate, xylylene diisocyanate and the like are preferable. As the aliphatic diisocyanate, ethylene diisocyanate, butane-1,4-diisocyanate, hexamethylene diisocyanate and the like are preferable. As the alicyclic diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4′-diisocyanate, 1,3-bis (isocyanatemethyl) cyclohexane, hydrogenated xylylene diisocyanate, methylcyclohexane diisocyanate, norbornane diisocyanate and the like are preferable. These may be trimers to form an isocyanurate ring structure. These polyisocyanates can be used alone or in admixture of two or more. Of these, isocyanurate of tolylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, hexamethylene diisocyanate, hexamethylene diisocyanate is preferable.

The amine chain extender is not limited to the following, but preferably has a molecular weight of 500 or less, and examples thereof include diamines and polyfunctional amines. Examples of the diamine chain extender include ethylene diamine, propylene diamine, hexamethylene diamine, pentamethylene diamine, isophorone diamine, dicyclohexylmethane-4,4′-diamine, p-phenylene diamine, and the like. A diamine chain extender having a hydroxyl group such as ethylenediamine can also be used. These chain extenders can be used alone or in admixture of two or more.

<Polyamide resin>
The polyamide resin is not limited to the following, but is preferably a thermoplastic polyamide soluble in an organic solvent that can be obtained by polycondensation of a polybasic acid and a polyvalent amine. In particular, it is preferably a polyamide resin containing an acid component containing a polymerized fatty acid and / or dimer acid and a reaction product of an aliphatic and / or aromatic polyamine, and further contains a part of primary and secondary monoamines. Is preferred.

Polybasic acid used as a raw material for polyamide resin is not limited to the following, but adipic acid, sebacic acid, azelaic acid, phthalic anhydride, isophthalic acid, suberic acid, glutaric acid, fumaric acid, pimelin Acid, oxalic acid, malonic acid, succinic acid, maleic acid, terephthalic acid, 1,4-cyclohexyldicarboxylic acid, trimellitic acid, dimer acid, hydrogenated dimer acid, polymerized fatty acid, etc., among them dimer acid or polymerization A polyamide resin containing a fatty acid-derived structure as a main component (50 mass% or more in the polyamide resin) is preferable. Here, the polymerized fatty acid is obtained by a cyclization reaction or the like of unsaturated fatty acid fatty acid, and includes monobasic fatty acid, dimerized polymerized fatty acid (dimer acid), trimerized polymerized fatty acid and the like. As the fatty acid constituting the dimer acid or the polymerized fatty acid, those derived from natural oils such as those derived from soybean oil, palm oil, and rice bran oil can be preferably mentioned, and those obtained from oleic acid and linoleic acid are preferred.
A monocarboxylic acid can be used in combination with the polybasic acid. Examples of the monocarboxylic acid used in combination include acetic acid, propionic acid, lauric acid, palmitic acid, benzoic acid, and cyclohexanecarboxylic acid.

Examples of the polyvalent amine include polyamines and primary or secondary monoamines. Examples of the polyamine used in the polyamide resin include aliphatic diamines such as ethylenediamine, propylenediamine, hexamethylenediamine, and methylaminopropylamine, and aliphatic polyamines such as diethylenetriamine and triethylenetetramine. Cyclohexylenediamine, isophoronediamine and the like. Examples of araliphatic polyamines include xylylenediamine, and examples of aromatic polyamines include phenylenediamine and diaminodiphenylmethane. Furthermore, examples of primary and secondary monoamines include n-butylamine, octylamine, diethylamine, monoethanolamine, monopropanolamine, diethanolamine, dipropanolamine and the like.

Further, the polyamide resin preferably has a softening point of 80 to 140 ° C., and the ink film becomes strong within the range. Further, from the viewpoint of solubility of the polyamide resin, the weight average molecular weight is preferably in the range of 2,000 to 50,000. It is still more preferable that it is 2,000-10,000. When the softening point is 80 ° C. or higher, the ink film of the printed material has good surface tackiness and prevents blocking. When the softening point is 140 ° C. or lower, the ink film becomes soft and the adhesion to the substrate is improved. When the weight average molecular weight is 2,000 or more, the ink film strength is good, and the scratch resistance, heat resistance, and high-speed printability are improved. When the molecular weight is 50,000 or less, the viscosity of the ink can be lowered, and the storage stability is improved. In addition, a softening point represents the value measured by JISK2207 (ring ball method).

<Cellulosic resin>
Examples of the cellulose resin include cellulose acetate propionate, cellulose acetate butyrate and other cellulose ester resins, nitrocellulose, hydroxyalkyl cellulose, and carboxyalkyl cellulose. The cellulose ester resin preferably has an alkyl group, and examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a pentyl group, and a hexyl group. May have a substituent.
Of the above, cellulose acetate propionate, cellulose acetate butyrate, and nitrocellulose are preferred as the cellulose resin. Particularly preferred is nitrocellulose. The molecular weight is preferably 5,000 to 200,000 in terms of weight average molecular weight, more preferably 10,000 to 50,000. Moreover, the thing whose glass transition temperature is 120 to 180 degreeC is preferable. This is because the combined use with a polyurethane resin or a polyamide resin improves blocking resistance, scratch resistance and other ink coating physical properties.

(Nitrocellulose)
The above nitrocellulose is preferably obtained by reacting natural cellulose with nitric acid to obtain a nitrate ester in which three hydroxyl groups in the 6-membered ring of anhydrous glucopyranose groups in natural cellulose are substituted with nitrate groups. The degree of polymerization is preferably 20 to 200, more preferably 30 to 150. An average polymerization degree of 20 or more is preferable because the strength of the ink film is improved and the scratch resistance is improved. Moreover, when the average degree of polymerization is 200 or less, solubility in a solvent, low-temperature stability of the ink, and compatibility with the combined resin are preferable. The nitrogen content is preferably 10.5 to 12.5% by mass.

<Vinyl chloride-vinyl acetate copolymer resin>
The vinyl chloride-vinyl acetate copolymer resin is not particularly limited as long as vinyl chloride and vinyl acetate are copolymerized. The molecular weight is preferably 5,000 to 100,000 in terms of weight average molecular weight, more preferably 10,000 to 70,000. In the solid content of 100% by mass of the vinyl chloride-vinyl acetate copolymer resin, 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. In this case, solubility in an organic solvent is improved, and adhesion to a base material, film properties, scratch resistance, and the like are improved.
Moreover, since the solubility to an organic solvent improves, what contains the hydroxyl group derived from a vinyl alcohol structure by saponification reaction, modification | denaturation reaction, or copolymerization is still more preferable, and it is preferable that it is 20-200 mgKOH / g as a hydroxyl value. The glass transition temperature is preferably 50 ° C to 90 ° C.

<Rosin resin>
The rosin resin is not particularly limited as long as it has a rosin skeleton, but rosin-modified maleic resin, rosin ester, rosin phenol, polymerized rosin and the like are preferable. The softening point (by ring and ball method) is preferably 90 to 200 ° C. This is to improve the blocking resistance. The rosin resin is preferably used in combination with a polyurethane resin.

<Hydrocarbon wax>
The hydrocarbon wax refers to a hydrocarbon wax having a hardness (penetration) of 0.5 to 12. Examples include, but are not limited to, polyethylene wax, Fischer-Tropsch wax, paraffin wax, microstalline wax, polypropylene wax, and the like. Of these, hydrocarbon waxes including polyethylene wax and / or Fischer-Tropsch wax are preferred. The said hydrocarbon wax contains 0.1-2.5 mass% in gravure ink. It is preferably contained in an amount of 0.3 to 2.5% by mass because the adhesiveness to the substrate, the scratch resistance and the temporal stability of the ink are compatible.

The hardness (penetration) of the hydrocarbon wax refers to a value measured according to JISK2207. When the value is in the range of 0.5 to 12 (unit: 10-1 mm), the affinity / compatibility with the binder resin is good, and further, the adhesive to various base materials due to the synergistic effect with the chlorinated polyolefin resin. Properties and scratch resistance are improved in both directions. The hydrocarbon wax preferably has a density at 23 ° C. defined in JIS K7112 (Method B) of 900 to 990 kg / m ³ . More preferably, it is 925-990 kg / m < ³ >. This is because appropriate crystallinity is exhibited in this density range, and it has more affinity with the binder resin and the chlorinated polyolefin resin. The hydrocarbon wax preferably has a melting point in DSC measurement of 90 to 150 ° C, more preferably 100 to 125 ° C. The melting point of the hydrocarbon wax represents the melting point of the peak top (minimum value) of the endothermic peak in the DSC temperature rising curve.
Moreover, in order to improve the gloss and printability (for example, doctor streak) of the gravure ink printing layer, the average particle size is preferably 0.5 to 12 μm, and more preferably 1 to 10 μm. Moreover, 2-8 micrometers is still more preferable. In addition, the average particle diameter in hydrocarbon wax represents the value of D50 in the measurement by the laser diffraction / light scattering method.

The mass ratio of the hydrocarbon wax to the chlorinated polyolefin resin is preferably 90:10 to 10:90, more preferably 85:15 to 15:85 for the hydrocarbon wax: chlorinated polyolefin resin. is there.

The polyethylene wax is not particularly limited, and examples thereof include high-density polymerized polyethylene, low-density polymerized polyethylene, oxidized polyethylene, acid-modified polyethylene, and special monomer-modified polyethylene. The polyethylene wax preferably has a density at 23 ° C. defined in JIS K7112 (Method B) of 925 to 990 kg / m ³ , and a melt viscosity at 140 ° C. measured according to JIS K6862 is 50 to 8000 mPa · s. It is preferable that it is s. Moreover, the polyethylene wax (b1) may have an acid value. When it has an acid value, it is preferable that an acid value is 0.5-70 mgKOH / g. The polyethylene wax (b1) preferably has a melting point in DSC measurement of 90 to 150 ° C, more preferably 100 to 125 ° C.

Fischer-Tropsch wax is a wax produced using carbon monoxide and hydrogen as raw materials by the Fischer-Tropsch manufacturing method, and has a substantially saturated, straight-chain molecular structure. Due to its straight chain structure, it has a high melting point, low viscosity and is hard. Fischer-Tropsch wax does not deteriorate even when exposed to heat for a long period of time, and exhibits extremely high thermal stability. The Fischer-Tropsch wax preferably has a number average molecular weight of 400 to 2,000. The Fischer-Tropsch wax preferably has a density of 925 to 990 kg / m ³ at 23 ° C. as defined in JIS K7112 (Method B). Fischer-Tropsch wax may have an acid value. When it has an acid value, it is preferably 0.5 to 50 mgKOH / g. Further, the Fischer-Tropsch wax preferably has a melting point of 90 to 130 ° C., more preferably 100 to 120 ° C. in DSC measurement.

There is no particular limitation on the method of adding the hydrocarbon wax to the gravure ink. In the pigment dispersion process of the ink, the hydrocarbon wax may be mixed and dispersed together with the pigment and the binder resin. What was dispersed with a solvent may be added to and included in the gravure ink. The dispersion method is not particularly limited, and a disper, roller mill, ball mill, pebble mill, attritor, sand mill, or the like can be used.

<Chlorinated polyolefin resin>
The chlorinated polyolefin resin in the present application refers to a polyolefin resin in which at least a part of hydrogen atoms are substituted with chlorine atoms. When the weight average molecular weight of the chlorinated polyolefin is 5,000 to 100,000, the compatibility with the binder resin and the affinity with the hydrocarbon wax are good. It is still more preferably 5,000 to 70,000, and even more preferably 7,000 to 50,000. Moreover, since the chlorinated polyolefin resin improves the adhesiveness to a base material, it is preferable that the chlorine content rate is 25-45 mass%. In addition, from the viewpoint of solubility in a non-toluene organic solvent, the chlorine content is more preferably 26 to 43% by mass. Here, the chlorine content refers to the content% by mass of chlorine atoms in 100% by mass of the chlorinated polyolefin resin. Further, from the viewpoint of the balance with blocking resistance, the chlorinated polyolefin resin is contained in an amount of 0.1 to 2.5% by mass, preferably 0.2 to 2.3% by mass, in 100% by mass of the ink.

In the present specification, the chlorinated polyolefin resin preferably has a structure in which hydrogen of an α-olefin polymer represented by the following general formula (2) is substituted with chlorine.
General formula (2)

CH ₂ = ^{CH-R 3}

(In the formula, R ³ is an alkyl group having 1 or more carbon atoms.)

Since the chlorinated polyolefin resin has a flexible alkyl group as a branched structure, the chlorinated polyolefin resin is a flexible resin even at a low temperature, and improves the adhesion of the substrate with the above-mentioned use amount. The structure of the polyolefin resin in the chlorinated polyolefin resin is not particularly limited. For example, a resin containing a homopolymer or copolymer of an α-olefin unsaturated hydrocarbon such as polypropylene, poly-1-butene, poly-4-methyl-1-pentene is preferable. Among these, those containing a polypropylene structure (that is, a chlorinated polypropylene structure) are particularly preferable. In this case, the adhesive force to various base materials is improved by a synergistic effect by the combined use with the hydrocarbon wax.

<Fatty acid amide>
The organic solvent-based gravure ink of the present invention preferably further contains a fatty acid amide. The fatty acid amide used preferably has an aliphatic hydrocarbon group having 10 to 25 carbon atoms and an amide group. The fatty acid amide is dissolved or dispersed in the gravure ink, but after printing, it is considered that the fatty acid amide is oriented on the surface of the ink film and develops slipperiness to improve blocking resistance.

As fatty acid amides, lauric acid amide (melting point 87 ° C.), palmitic acid amide (melting point 100 ° C.), stearic acid amide (melting point 101 ° C.), behenic acid amide (melting point 110 ° C.), hydroxy stearic acid amide (melting point 107 ° C.) Oleic acid amide (melting point: 75 ° C.), erucic acid amide (melting point: 81 ° C.) and the like are particularly preferable. The content of the fatty acid amide is preferably from 0.1 to 2.5% by mass and more preferably from 0.1 to 2% by mass in 100% by mass of the gravure ink.

<Pigment>
The gravure ink of the present invention contains a pigment. The mass ratio of the binder resin to the pigment (binder resin / pigment) is preferably 99/1 to 10/90. Furthermore, it is more preferable that it is 80 / 20-20 / 80. The pigment can be any of organic pigments, inorganic pigments and extender pigments, but inorganic pigments containing titanium oxide, and extender pigments include silica, barium sulfate, kaolin, clay, calcium carbonate, carbonate Magnesium and the like are preferable. As the organic pigment, it is preferable to use an organic compound or an organic metal complex. However, the case where the pigment is an aluminum vapor-deposited film strip having a coating layer made of nitrocellulose is excluded.

Organic pigments are not limited to the following examples, but soluble azo, insoluble azo, azo, phthalocyanine, halogenated phthalocyanine, anthraquinone, ansanthrone, dianthraquinonyl, anthrapyrimidine, perylene , Perinone, quinacridone, thioindigo, dioxazine, isoindolinone, quinophthalone, azomethineazo, flavanthrone, diketopyrrolopyrrole, isoindoline, indanthrone, carbon black, etc. Is mentioned. Also, for example, Carmine 6B, Lake Red C, Permanent Red 2B, Disazo Yellow, Pyrazolone Orange, Carmine FB, Chromophthal Yellow, Chromophthal Red, Phthalocyanine Blue, Phthalocyanine Green, Dioxazine Violet, Quinacridone Magenta, Quinacridone Red, Indance Long blue, pyrimidine yellow, thioindigo bordeaux, thioindigo magenta, perylene red, perinone orange, isoindolinone yellow, aniline black, diketopyrrolopyrrole red, daylight fluorescent pigment, and the like.

The hue in the gravure ink of the present invention may be selected from gravure inks of other hues as necessary (a total of five colors including yellow, red, indigo, black, and white as basic colors, red (orange), grass (outside as process gamut) (Green), purple (three colors), transparent yellow, peony, vermilion, brown, and pearl).

On the other hand, examples of the inorganic pigment include white inorganic pigments such as titanium oxide, zinc oxide, zinc sulfide, barium sulfate, calcium carbonate, chromium oxide, and silica. Of the inorganic pigments, the use of titanium oxide is particularly preferred. Titanium oxide has a white color and is preferable from the viewpoint of coloring power, hiding power, chemical resistance, and weather resistance. From the viewpoint of printing performance, the titanium oxide is preferably subjected to silica and / or alumina treatment.

Examples of inorganic pigments other than white include, for example, aluminum particles, mica (mica), bronze powder, chrome vermillion, chrome lead, cadmium yellow, cadmium red, ultramarine, bitumen, red, oxide iron, black iron, titanium oxide, Zinc oxide and the like can be mentioned, and aluminum is in the form of powder or paste, but it is preferably used in the form of paste from the viewpoint of handleability and safety, and may be either a leafing type or a non-leafing type.

The pigment is an amount sufficient to ensure the density and coloring power of the gravure ink, that is, 1 to 50% by mass relative to the total mass of the ink composition, and 10 to 90% by mass in the solid content mass ratio in the ink composition It is preferable that it is contained in the ratio. These pigments can be used alone or in combination of two or more.

<Organic solvent>
The gravure ink of the present invention contains an organic solvent. Although not limited to the following, organic solvents used include aromatic organic solvents such as toluene and xylene, ketone organic solvents such as methyl ethyl ketone and methyl isobutyl ketone, ethyl acetate, n-propyl acetate, isopropyl acetate, Known organic solvents such as isobutyl acetate, ester organic solvents, alcohol organic solvents such as methanol, ethanol, n-propanol, isopropanol and n-butanol, and glycol ether solvents such as ethylene glycol monopropyl ether and propylene glycol monomethyl ether They can be used and may be used in combination. In particular, since the temporal stability of the gravure ink is improved when a hydrocarbon wax is contained, an organic solvent not containing an aromatic organic solvent such as toluene or xylene (non-toluene organic solvent) is preferable, and an ester organic solvent is used. And a mixed organic solvent containing an alcohol-based organic solvent in a mass ratio of 50:50 to 90:10 is more preferable. Furthermore, the glycol ether organic solvent may be contained in an amount of 5% by mass or less in 100% by mass of the ink.

<Additives>
The gravure ink of the present invention can appropriately contain conventionally known additives as additives, and in the production of gravure inks, additives such as pigment derivatives, dispersants, wetting agents, adhesion aids, leveling agents as necessary. Antifoaming agents, antistatic agents, viscosity modifiers, metal chelates, trapping agents, antiblocking agents, wax components other than those described above, isocyanate curing agents, silane coupling agents, and the like can be used.

<Metal chelate>
It is preferable to use a metal chelate for the gravure ink of the present invention. The metal chelate is preferably a titanium chelate. For example, titanium alkoxide such as tetraisopropyl titanate, tetranormal butyl titanate, butyl titanate dimer, tetra (2-ethylhexyl) titanate, tetramethyl titanate, tetrastearyl titanate, triethanolamine titanate, titanium acetyl acetate toner, titanium tetraacetylacetate Examples thereof include titanium chelates such as narate, tetraisopropoxy titanium, titanium ethyl acetoacetate, titanium lactate, octylene glycol titanate, n-butyl phosphate titanium, and propanedioxitanium bis (ethyl acetyl acetate). Among the metal chelates, metal chelates that do not generate acetylacetone after the crosslinking reaction are preferable from an environmental viewpoint.
In order to crosslink with the active hydrogen possessed by the binder resin, the content of the metal chelate is preferably 0.1 to 5% by mass and more preferably 0.5 to 2% by mass in the gravure ink. When the content is 0.1% by mass or more, the heat resistance, oil resistance, and vinyl chloride blocking resistance are improved. When the content is 5% by mass or less, the stability over time of the ink is improved. By using these metal chelates, adhesion to a plastic substrate or a surface-coated paper substrate is enhanced, and the strength of the formed ink film is improved.

<Manufacture of gravure ink>
The gravure ink of the present invention can be produced by dissolving and / or dispersing a binder resin, hydrocarbon wax or the like in a liquid medium. For example, pigment, polyurethane resin, vinyl chloride-vinyl acetate copolymer resin, polyethylene wax and dispersed as necessary, and the pigment dispersion is polyurethane resin, polyethylene wax dispersion, organic solvent as required, other resins A gravure ink can be produced by blending with additives. In addition, the viscosity and color of the gravure ink are adjusted by appropriately adjusting the size of the grinding media of the disperser, the filling rate of the grinding media, the dispersion treatment time, the discharge speed of the pigment dispersion, the viscosity of the pigment dispersion, and the like. be able to.
The hydrocarbon wax used in the present invention is finely dispersed in advance in an organic solvent, and is generally used as a disperser preferably added appropriately during the production process of gravure ink, for example, a roller mill, a ball mill, A pebble mill, an attritor, a sand mill, etc. can be used. It is preferable to manufacture using a sand mill.

The viscosity of the gravure ink is preferably in the viscosity range of 40 to 500 cps with a B-type viscometer at 25 ° C. from the viewpoint of the temporal stability of the gravure ink. More preferably, it is 50-400 cps. This viscosity range corresponds to a viscosity at Zahn cup # 4 of about 9 to 40 seconds. In addition, the viscosity of gravure ink can be adjusted by selecting suitably the kind and quantity of the raw material used, for example, quantity, such as a pigment, binder resin, and an organic solvent. The viscosity of the ink can also be adjusted by adjusting the particle size and particle size distribution of the organic pigment in the ink.

<Printed matter>
After printing on the base material using the gravure ink of the present invention, a volatile component is removed to form a printed layer, thereby obtaining a printed matter. The printing method is a gravure printing method, for example, diluted with a diluting solvent to a viscosity and concentration suitable for gravure printing, alone or mixed and supplied to each printing unit and applied. Then, it can be obtained by fixing the film by drying in an oven.

<Base material>
The substrate is not particularly limited, but is preferably a film substrate, for example, a polyolefin substrate such as polyethylene or polypropylene, a polyester substrate such as polyethylene terephthalate, polycarbonate or polylactic acid, polystyrene, AS resin, ABS resin, etc. Examples thereof include film base materials such as polystyrene base materials, nylon base materials, polyamide base materials, polyvinyl chloride base materials, polyvinylidene chloride base materials, cellophane base materials, and film base materials made of these composite materials. The plastic substrate may be corona-treated or untreated. Further, it may be a stretched base material or an unstretched base material.
The base material may be further deposited with a metal or metal oxide such as silica, alumina, or aluminum, and the deposition surface may be coated with a paint such as polyvinyl alcohol. In general, the surface of the substrate to be printed is often subjected to a surface treatment such as corona treatment. Further, a plastic film such as antifogging agent coating and kneading, matting agent surface coating and kneading in advance. Films obtained by processing can also be used.
The base material may be a single layer or a laminate (base material layer) in which two or more base materials are laminated. The base materials constituting the base material layer may be the same or different.

Antifogging agents are preferably surfactants, for example, ionic surfactants such as polyhydric alcohol fatty acid esters such as sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene fatty acid esters, glycerin fatty acid esters, and ethylene oxide adducts. One or more agents are used.

EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, this invention is not limited to these Examples. Parts and% represent parts by mass and mass%, respectively, unless otherwise noted. Examples 1 to 20 and 27 are reference examples.

(Hydroxyl value)
It calculated | required according to JISK0070.
(Acid value)
It calculated | required according to JISK0070.
(Amine number)
The amine value was determined according to the following method according to JISK0070 in terms of mg of potassium hydroxide in the same amount as the equivalent of hydrochloric acid required to neutralize the amino group contained in 1 g of resin.
0.5-2 g of the sample was precisely weighed (sample solid content: Sg). To a precisely weighed sample, 50 mL of a mixed solution of methanol / methyl ethyl ketone = 60/40 (mass ratio) was added and dissolved. Bromophenol blue was added as an indicator to the obtained solution, and the obtained solution was titrated with a 0.2 mol / L ethanolic hydrochloric acid solution (titer: f). The point at which the color of the solution changed from green to yellow was taken as the end point, and the amine titer was determined by the following (formula 2) using the titration amount (AmL) at this time.
(Formula 2) Amine number = (A × f × 0.2 × 56.108) / S [mgKOH / g]

(Weight average molecular weight)
The weight average molecular weight was determined as a converted molecular weight using polystyrene as a standard substance by measuring a molecular weight distribution using a GPC (gel permeation chromatography) apparatus (HLC-8220 manufactured by Tosoh Corporation). The measurement conditions are shown below.
Column: The following columns were used in series.
Guard column HXL-H manufactured by Tosoh Corporation
Tosoh Corporation TSKgelG5000HXL
Tosoh Corporation TSKgelG4000HXL
TSKgel G3000HXL manufactured by Tosoh Corporation
TSKgel G2000HXL manufactured by Tosoh Corporation
Detector: RI (differential refractometer)
Measurement conditions: Column temperature 40 ° C
Eluent: Tetrahydrofuran Flow rate: 1.0 mL / min

(Glass-transition temperature)
The glass transition temperature (Tg) was determined by DSC (differential scanning calorimetry measurement). In addition, the measuring machine uses DSC8231 made by Rigaku Corporation, measuring temperature range -70 to 250 ° C, temperature rising rate 10 ° C / min, the midpoint between endothermic start temperature and end temperature based on glass transition in DSC curve is glass. The transition temperature was used.

(Synthesis example 1) [Polyurethane resin PU1]
200 parts of polypropylene glycol (hereinafter “PPG700”) having a number average molecular weight of 700, 127 parts of isophorone diisocyanate (hereinafter “IPDI”), and 81.8 parts of ethyl acetate were reacted at 80 ° C. for 4 hours under a nitrogen stream, and terminal isocyanate A resin solution of urethane prepolymer was obtained. Next, 49.5 parts of isophoronediamine (hereinafter “IPDA”), 3 parts of 2-ethanolamine, and 803.9 parts of a mixed solvent of ethyl acetate / isopropanol (hereinafter “IPA”) = 50/50 (mass ratio) were mixed. The resulting resin solution of the terminal isocyanate urethane prepolymer was gradually added at 40 ° C. and then allowed to react at 80 ° C. for 1 hour, solid content 30%, amine value 3.5 mgKOH / g, hydroxyl value 7.3 mgKOH / G, a polyurethane resin solution PU1 having a weight average molecular weight of 40000 was obtained. The glass transition temperature was -32 ° C.

(Synthesis example 2) [Polyurethane resin PU2]
150 parts of a polyester polyol (hereinafter referred to as “PMPA”) having a number average molecular weight of 1000 obtained by a reaction of adipic acid and 3-methyl-1,5-pentanediol, 50 parts of PPG 700, 103.4 parts of IPDI, and 75 of ethyl acetate .8 parts were reacted under a nitrogen stream at 80 ° C. for 4 hours to obtain a resin solution of a terminal isocyanate urethane prepolymer. Next, the resin solution of the terminal isocyanate urethane prepolymer was gradually added at 40 ° C. to a mixture of 44.6 parts of IPDA and 736.2 parts of a mixed solvent of ethyl acetate / IPA = 50/50 (mass ratio). And a polyurethane resin solution PU2 having a solid content of 30%, an amine value of 9.5 mgKOH / g, a hydroxyl value of 0.0 mgKOH / g, and a weight average molecular weight of 50000 was obtained. The glass transition temperature was −21 ° C.

(Example 1) [Preparation of gravure ink S1]
30 parts polyurethane resin solution PU1 (solid content 30%) as binder resin, 0.8 parts polyethylene wax (A-C400A manufactured by Honeywell) as hydrocarbon wax, chlorinated polypropylene resin (Nippon Paper Industries) Product name: 370M Chlorine content 30%, solid content 50%) is 0.5 parts in terms of solid content, C.I. I. 10 parts of Pigment Blue 15: 4 and 58.7 parts of a solution of methyl ethyl ketone (hereinafter “MEK”) / n-propyl acetate (hereinafter “NPAC”) / IPA = 40/40/20 (mass ratio) were mixed, and Eiger Mill To obtain a gravure ink S1.

The hydrocarbon waxes used in the following examples were those listed in Table 1-1. The hydrocarbon waxes used in the comparative examples were those listed in Table 1-2. In addition,
Hardness (penetration) was measured at 25 ° C. according to JIS K2207.
The density was measured at 23 ° C. according to JIS K7112 (Method B).
-Melting | fusing point calculated | required melting | fusing point by DSC (differential scanning calorimetry measurement). The measuring device was obtained using DSC8231 manufactured by Rigaku Corporation. (Measuring temperature range 25-180 ° C, heating rate 10 ° C / min)
The average particle size was measured by a laser diffraction / scattering method using a 10% solid dispersion obtained by adding and dispersing ethyl acetate to a hydrocarbon wax, and the value of D50 was defined as the average particle size. D50
Represents the median diameter in the volume-based cumulative distribution. The measuring machine used was Microtrack MT3000II manufactured by Microtrack Bell.

Examples 2 to 27 [Production of gravure inks S2 to S27]
Except having changed into the raw material and mixing | blending which were described in Table 2, the gravure inks S2-S27 were obtained by the method similar to Example 1, respectively. Abbreviations in the table represent the following.
Polyamide A: Polyamide resin containing a dimer acid-derived structural unit of oleic acid and linoleic acid as raw materials and having an amine value of 3.5 mg KOH / g, softening point 116 ° C. weight average molecular weight 6,000 (solid 30% isopropanol solution)
・ Solvain TAO: Vinyl chloride-vinyl acetate copolymer resin manufactured by Nissin Chemical Co. Composition: Copolymer resin of vinyl chloride / vinyl acetate / vinyl alcohol = 91/2/7 (mass ratio) (solid content 30% ethyl acetate solution) Glass transition temperature 78 ° C
・ Marquide No. 5: Rosin modified maleic resin manufactured by Arakawa Chemical Co., Ltd. Softening point 145 ° C. (30% solid content ethyl acetate solution)
DLX5-8: Nitrocellulose manufactured by ICI Novel enterprises
Nitrogen content 12.0% Glass transition temperature 150 ° C (Solid content 30% isopropanol solution)
-814B: Nippon Paper Industries Co., Ltd. chlorinated polypropylene resin Weight average molecular weight 18,000 Chlorine content 41%
・ 370M: Chlorinated polypropylene resin manufactured by Nippon Paper Industries Co., Ltd. Weight average molecular weight 10,000 Chlorine content 30%
803LT: Chlorinated polyolefin resin manufactured by Nippon Paper Industries Co., Ltd. Weight average molecular weight 55,000 Chlorine content 26.5%
・ Lauric acid amide: Fatty acid amide Melting point 99 ° C

(Example 28) <Printing of gravure ink>
The gravure ink S1 obtained above is diluted with a mixed solvent of MEK / NPAC / IPA = 40/40/20 (mass ratio) so that the viscosity is 16 seconds (25 ° C., Zaan Cup No. 3). Printing on the following base materials (corona discharge treated surface in the case of OPP) at a printing speed of 80 m / min using a gravure printing machine equipped with the Helio 175 line gradation plate (plate-type compressed gradation 100% to 3%) Printed materials J1 (OPP) and K1 (CPP) were obtained.
<Base material>
・ OPP: Biaxially stretched polypropylene (OPP) film with a single-sided corona discharge treatment (FOR Thickness 25 μm, manufactured by Futamura Chemical)
CPP: unstretched polypropylene (CPP) film without corona treatment (CP-S thickness 30 μm, manufactured by Mitsui Chemicals, Inc.)

(Examples 29 to 54)
About gravure ink S2-S27 described in Table 2, it printed by the printing structure of Table 4, and printed matter J2-J27 (OPP) and K2-K27 (CPP) were obtained.

(Comparative Examples 1 to 11) [Preparation of gravure inks T1 to T11]
Gravure inks T1 to T11 were obtained in the same manner as in Example 1 except that the raw materials shown in Table 3 were used. Abbreviations in the table represent the following.
・ 803M: Chlorinated polypropylene resin manufactured by Nippon Paper Industries Co., Ltd. Weight average molecular weight 160,000 Chlorine content 30% (Super Clone 803M)

(Comparative Examples 12-22)
For the gravure inks T1 to T11 described in Table 3, surface printing is performed in the same manner as in Example 28 with the printing configuration described in Table 5, and printed matter JJ1 to JJ11 (OPP), KK1 to KK11 (CPP). Got.

<Evaluation>
Using the gravure inks S1 to S27, T1 to T11, and printed materials J1 to J27 (OPP), printed materials K1 to K27 (CPP), printed materials JJ1 to JJ11 (OPP), printed materials KK1 to KK11 (CPP), the following evaluations were made. went.

<Stability of ink over time>
About gravure ink S1-S27, T1-T11, each was put into the airtight container, and it preserve | saved at 40 degreeC for 10 days. Thereafter, the viscosity was measured to evaluate the change in viscosity before storage. The viscosity was measured at 25 ° C. with Zahn Cup No. Performed with 4 outflow seconds. All the inks had a viscosity of 40 to 500 cps (25 ° C.) in a B-type viscometer before storage.
[Criteria]
5. Viscosity change is less than 2 seconds (good)
4). Viscosity difference is 2 seconds or more and less than 5 seconds (practical)
3. Viscosity difference is 5 seconds or more and less than 10 seconds (somewhat poor)
2. Viscosity difference is 10 seconds or more and less than 15 seconds (defect)
1. Viscosity difference is 15 seconds or more (very bad)
In addition, 5 and 4 are ranges in which there is no practical problem.

<Doctor streak evaluation>
Doctor streak evaluation was performed on the gravure inks S1 to S27 and T1 to T11. The dilution solvent was MEK: NPAC: IPA = 40: 40: 20, the viscosity was 16 seconds (25 ° C.) with Zaan Cup # 3, and the doctor streak after 60 minutes at 100 m / min. The area of was visually determined and evaluated. The doctor blade was evaluated using a commercially available ceramic product.
The doctor streak is a thin streak-like printing defect derived from ink that can occur on the plate in the rotating direction when the ink is scraped off from the rotating plate with a doctor blade.
[Criteria]
5. No doctor streaks or thin doctor streaks is about 1 to 2 (good)
4). 3 to 5 thin doctor lines (practical)
3. 5-10 thin doctor lines (somewhat bad)
2. There are 1 to 3 dark doctor lines (defective)
1. There are 4 or more dark doctor lines (very bad)
In addition, 5 and 4 are ranges in which there is no practical problem.

<Abrasion resistance>
Using printed materials J1 to J27 (OPP), printed materials K1 to K27 (CPP), printed materials JJ1 to JJ11 (OPP), and printed materials KK1 to KK11 (CPP), the surface of the printed layer is rubbed with nails at three places, and the printed layer is damaged. The degree was evaluated.
[Criteria]
5. No damage to the printed layer (good)
4). The print layer is not scratched, but a slight nail mark remains. (Practical acceptable)
3. The print layer is scratched and the print layer surface is slightly scratched. (Slightly bad)
2. The printed layer is scratched and the substrate is slightly visible. (Bad)
1. The printed layer is scratched and the substrate is clearly visible. (Very bad)
In addition, 5 and 4 are ranges in which there is no practical problem.

<Adhesiveness>
For printed materials J1 to J27 (OPP), printed materials K1 to K27 (CPP), printed materials JJ1 to JJ11 (OPP), and printed materials KK1 to KK11 (CPP), each 3 hours after printing, an adhesive tape having a width of 12 mm (Nichiban) The cellophane tape) was affixed and the appearance of the printed surface when it was rapidly peeled off was visually judged. The criteria for determination were as follows.
[Criteria]
5. The ink film on the printing surface does not peel off at all (good)
4). The peeled area of the ink coating is 1% or more and less than 5% (practical)
3. Ink film peeling area of 5% or more and less than 20% (slightly poor)
2. Ink film peeling area of 20% or more and less than 50% (defect)
1. The ink film is peeled off by 50% or more (very bad)
In addition, 5 and 4 are ranges in which there is no practical problem.

The organic solvent-based gravure ink of the present invention was able to satisfy both properties of blocking resistance and adhesiveness evenly even on substrates having different surface properties such as polarity and stretched or unstretched substrates. Furthermore, even when hydrocarbon wax particles were contained, there was no doctor streak and the like, and a gravure ink excellent in printability could be provided.

Claims (7)

An organic solvent gravure ink containing a pigment, a binder resin, a hydrocarbon wax, and a chlorinated polyolefin resin and satisfying the following (1), (2) and (3) .
(1) hardness at 25 ° C. as defined in JISK2207 of hydrocarbon wax (penetration) is a 0.5 to 12, 0.1 to 2.5 mass hydrocarbon wax in gravure ink amount %contains.
(2) The weight average molecular weight of the chlorinated polyolefin resin is 5,000 to 100,000, containing 0.1 to 2.5% by weight in the gravure ink amount.
(3) The binder resin contains a polyamide resin and at least one resin selected from the group consisting of a vinyl chloride-vinyl acetate copolymer resin, a cellulose resin, and a rosin resin. The organic solvent-based gravure ink according to claim 1, which is used for surface printing. The organic solvent gravure ink according to claim 1 or 2, wherein the binder resin contains a polyamide resin and a cellulose resin, and the cellulose resin contains a nitrocellulose resin having a nitrogen content of 10.5 to 12.5. The organic solvent-based gravure ink according to any one of claims 1 to 3, wherein the polyamide resin has a softening point of 80 to 140 ° C, and the weight average molecular weight of the polyamide resin is 2,000 to 50,000. The polyamide resin is an organic solvent-based gravure ink according to any one of claims 1 to 4, wherein the polyamide resin contains 50% by mass or more of a structure derived from dimer acid or polymerized fatty acid. Further comprising a metal chelate, according to claim 1-5 organic solvent-based gravure ink according to any one. The printed matter which has a printing layer which consists of an organic-solvent gravure ink in any one of Claims 1-6 on a base material.