JP2000001642A - Printing ink and binder therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject binder having excellent adhesion to plastic films such as a polyester, nylon, polyethylene or polypropylene by including a terpenic resin and a polyurethane resin. SOLUTION: This binder is obtained by including (A) a terpenic resin (e.g. α-pinene or β-pinene) and (B) a polyurethane resin as principal components. The weight ratio A/B of the components A to B is preferably (1/99) to (70/30). The component A having 500-2,000 weight-average molecular weight is preferably used. The component B is prepared by reacting a polymeric diol with a diisocyanate compound, a chain extender and a chain terminator. The binder is used as a resin solution and is preferably regulated to 15-60 wt.% concentration of the resin solid content and 50-100,000 cP viscosity at 25 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applicable to any of polyethylene (hereinafter abbreviated as PE), polypropylene (hereinafter abbreviated as PP), polyester (hereinafter abbreviated as PET) and nylon (hereinafter abbreviated as NY) films. The present invention relates to a printing ink composition exhibiting good adhesiveness.

[0002]

2. Description of the Related Art In recent years, various types of plastic films have been developed as packaging materials as packaging contents have become more complicated and packaging technology has become more sophisticated. As a result, films suitable for the contents have been selected as appropriate. Became used.

Hitherto, rosin-modified maleic resin, nitrified cotton, polyurethane resin, chlorinated polyolefin, polyamide resin, vinyl chloride-vinyl acetate copolymer resin, polyester resin, etc. have been used as binders for such printing inks for plastic films. However, none of them has excellent adhesiveness to any of PP, PET and NY films as a printing material. For this reason, it is inevitable that inks that match the characteristics of the film used must be individually designed, and the types of these inks are diverse.

For example, a printing ink using a polyurethane resin as a binder has excellent adhesive strength to a PET film or an NY film by itself, but is insufficient for a general-purpose film such as a polyolefin film such as a PE film or a PP film. No strong adhesion. On the other hand, chlorinated polyolefins show good adhesion to polyolefin films, but do not have sufficient adhesion to PET and NY films.

[0005] Therefore, as a binder for printing ink, there has been proposed a binder in which a polyurethane resin and a chlorinated polyolefin are mixed or reacted to improve the adhesion to various printing materials. However, since chlorinated polyolefin contains chlorine, there are problems such as stability over time due to a dehydrochlorination reaction over time, corrosion of a filled container due to generated hydrogen chloride, and coloring of a resin. Moreover,
Chlorinated polyolefins generate chlorine gas during the recycling process and during combustion, which can cause dioxin generation and other adverse effects on the environment. From the standpoint of environmental protection, environmentally friendly printing inks that do not contain chlorine. Binders are required.

[0006]

SUMMARY OF THE INVENTION The present invention relates to PET, N
An object of the present invention is to provide a binder for printing ink which has excellent adhesiveness to various plastic films such as Y, PE, and PP, and is made of a non-chlorine resin.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in order to solve the above-mentioned problems of the prior art, and as a result, have found that a binder for a printing ink containing a mixture of a polyurethane resin and a terpene resin as a main component has been described. The inventors have found that all the problems of the prior art can be solved, and have completed the present invention.

That is, the present invention relates to a printing ink binder containing (1) a terpene resin and (2) a polyurethane resin as main components, and further to a printing ink using the printing ink binder.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The terpene resins (1) of the present invention include polymers of terpenes such as α-pinene, β-pinene, dipentene, limonene and the like, modified products thereof, and hydrides thereof. Can be Terpene polymers are usually produced by cationic polymerization of terpenes. Examples of the modified products include terpene phenol resins and aromatic modified terpene resins. The modified product is usually produced by a method of polymerizing a terpene in a reaction system in which a phenol or an aromatic vinyl monomer is present. Examples of phenols include phenol, bisphenol A, and alkylphenols such as cresol, xylenol, pt-butylphenol, p-octylphenol, and p-nonylphenol, and aromatic vinyl monomers include styrene, vinyltoluene, and the like. α-methylstyrene, dimethylstyrene and the like. It is preferable that the weight average molecular weight of these (1) terpene resins is usually about 500 to 2,000.

The polyurethane resin (2) of the present invention is not particularly limited, and various known polyurethane resins can be used. A polyurethane resin is generally obtained by reacting a polymer polyol, a diisocyanate compound, a chain extender and, if necessary, a chain terminator.

Examples of the high molecular polyol used in the production of the polyurethane resin include polyether polyols such as polymers or copolymers such as ethylene oxide, propylene oxide and tetrahydrofuran; ethylene glycol;
Diethylene glycol, triethylene glycol, 1,
2-propanediol, 1,3-propanediol,
1,3-butanediol, 1,4-butanediol, neopentyl glycol, pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, octanediol, 1,4-butynediol, di Various known low-molecular glycols saturated or unsaturated such as propylene glycol or alkyl glycidyl ethers such as n-butyl glycidyl ether and 2-ethylhexyl glycidyl ether; glycidyl monocarboxylates such as glycidyl versatate; Dibasic acids such as adipic acid, maleic acid, fumaric acid, phthalic anhydride, isophthalic acid, terephthalic acid, succinic acid, oxalic acid, malonic acid, glutaric acid, pimelic acid, azelaic acid, sebacic acid, suberic acid, etc. Corresponding acid anhydride and die Polyester polyols obtained by dehydration-condensation with an acid or the like; Polyester polyols obtained by ring-opening polymerization of a cyclic ester compound; Other polycarbonate polyols, polybutadiene glycols, bisphenol A to which ethylene oxide or propylene oxide is added Various known polymer polyols generally used for the production of polyurethane, such as glycols obtained by the above method, can be used.

In the case of a high molecular polyol obtained from a glycol and a dibasic acid among the above high molecular polyols, up to 5 mol% of the glycol can be replaced by the following various polyols. Examples include glycerin, trimethylolpropane, trimethylolethane, 1,2,6-hexanetriol, 1,2,4-butanetriol, sorbitol, pentaerythritol and the like.

The number average molecular weight of the high molecular polyol is as follows:
It is appropriately determined in consideration of the solubility, drying property, blocking resistance and the like of the obtained polyurethane, and is usually 700 to 100.
It is good to be about 00, preferably in the range of 1000 to 6000. If the number average molecular weight is less than 700, the printability tends to decrease due to the decrease in solubility.
If it exceeds 0000, drying properties and blocking resistance tend to decrease.

As the diisocyanate compound used in the production of the polyurethane resin, various known aromatic, aliphatic or alicyclic diisocyanates can be used. For example, 1,5-naphthylene 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, 2,4,4-trimethylhexamethylene diisocyanate, cyclohexane-1,4-diisocyanate, xylylene diisocyanate, hydrogen Xylylene diisocyanate, isophorone diisocyanate, lysine diisocyanate, Cyclohexyl-4,4 '
-Diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, methylcyclohexane diisocyanate, m-tetramethylxylylene diisocyanate, dimer isocyanate in which the carboxyl group of dimer acid is converted into an isocyanate group, and the like.

As the chain extender used for producing the polyurethane resin, various known ones can be used. For example, ethylenediamine, propylenediamine, hexamethylenediamine, triethylenetetramine, diethylenetriamine, isophoronediamine, dicyclohexylmethane-4,4'-diamine and the like can be mentioned. In addition, 2-hydroxyethylethylenediamine, 2-hydroxyethylpropylenediamine, di-2
Diamines having a hydroxyl group in the molecule such as -hydroxyethylethylenediamine, di-2-hydroxyethylpropylenediamine, 2-hydroxypropylethylenediamine, di-2-hydroxypropylethylenediamine and the like, and low-molecular-weight glycols described in the above-mentioned section of the polyester diols And dimer diamine in which a carboxyl group of dimer acid is converted into an amino group.

Further, examples of the chain terminator used as required include dialkylamines such as di-n-butylamine and alcohols such as ethanol and isopropyl alcohol.

As a method for producing the polyurethane resin, first, a polymer polyol and a diisocyanate compound are reacted under an excess of isocyanate groups to prepare a prepolymer having an isocyanate group at a terminal of the polymer polyol. In a suitable solvent with a chain extender and, if necessary, a polymerization terminator, and a polymer polyol, a diisocyanate compound, a chain extender and, if necessary, a polymerization terminator in a suitable solvent. Any one-step method of reacting at once can be employed, but the former method is preferred for the purpose of obtaining a uniform polymer solution. In these production methods, as a solvent used, aromatic solvents such as benzene, toluene, and xylene which are well known as solvents for printing inks; ester solvents such as ethyl acetate and butyl acetate; methanol, ethanol, Alcohol solvents such as isopropanol and n-butanol; ketone solvents such as acetone, methyl ethyl ketone and methyl isobutyl ketone can be used alone or in combination.

When the polyurethane resin is produced by the two-step method, the conditions for reacting the prepolymer with the chain extender and, if necessary, the polymerization terminator are not particularly limited. When the isocyanate group of 1 is equivalent, the total equivalent of the active hydrogen capable of reacting with the isocyanate group in the chain extender is preferably in the range of 0.5 to 2 equivalents. In the case of a group, it is preferably in the range of 0.5 to 1.3 equivalents. When the amount of the active hydrogen is less than 0.5 equivalent, the drying property, the blocking resistance, and the film strength are not sufficient, and when the amount of the active hydrogen exceeds 2 equivalents, the chain extender remains unreacted. It is not preferable because it may be caused.

The number average molecular weight of the polyurethane resin is determined based on the drying property, blocking resistance,
It is appropriately determined in consideration of the film strength, oil resistance, viscosity and the like, but is usually preferably in the range of 5,000 to 100,000.

The binder for printing ink of the present invention contains the above-mentioned (1) terpene resin and (2) polyurethane resin as main components. The use ratio of (1) and (2) is determined in consideration of the adhesiveness to olefin, PET, NY, and the like, and is usually expressed by weight ratio of (1) /
(2) is about 1/99 to 70/30, and 5/95
It is preferable to be in the range of 50/50. (1) If the proportion of the terpene-based resin is less than 1, the adhesiveness to olefin is not sufficient, and if it exceeds 70, the adhesiveness to PET, NY, etc. becomes insufficient.

Further, unless deviating from the performance of the binder for printing ink of the present invention, nitrified cotton, chlorinated polyethylene,
Chlorinated polypropylene, chlorinated polyolefin such as chlorinated ethylene / propylene, chlorosulfonated polyolefin, ethylene / vinyl acetate copolymer or its chloride or chlorsulfonate or maleic acid resin,
Resins such as a vinyl chloride / vinyl acetate copolymer can also be used in combination.

The printing ink binder of the present invention is usually used as a resin solution. The resin solid content concentration is not particularly limited, but may be appropriately determined in consideration of workability at the time of printing and the like, and is usually adjusted to about 15 to 60% by weight, and the viscosity is adjusted to about 50 to 100,000 cP / 25 ° C. Is practically suitable.

The binder for printing ink of the present invention thus obtained contains a colorant, a solvent, and, if necessary, a surfactant, a wax, and other additives for improving the ink fluidity and the ink surface film. Then, the printing ink is manufactured by kneading using an ordinary ink manufacturing apparatus such as a ball mill, an attritor, and a sand mill. In addition, it is preferable to mix | blend the compounding quantity of the binder of this invention of a printing ink so that the resin solid content may be 3-20 weight%.

[0024]

According to the present invention, PE as a print substrate
It is possible to provide a printing ink binder having excellent adhesiveness to any of various plastic films such as T, NY, PE, and PP. Further, since the binder for printing ink of the present invention has excellent adhesiveness, it is excellent in printing suitability and laminating process suitability.
Applicable to direct lamination, boil processing, retort processing, dry lamination processing, extrusion lamination processing, etc. Furthermore, since the binder for printing ink of the present invention does not use a chlorine-based resin, it has good stability and has no problem of corrosion of containers and the like.

[0025]

EXAMPLES The present invention will be described more specifically with reference to Production Examples, Examples and Comparative Examples, but the present invention is not limited to these Examples. The parts and percentages are based on weight.

Production Example 1 In a round bottom flask equipped with a stirrer, thermometer and nitrogen gas inlet tube, a poly (3-methyl-1,5-pentylene adipate) glycol having a molecular weight of 2,000 (manufactured by Kuraray Co., Ltd.) 1000 parts) and 222 parts of isophorone diisocyanate were charged under nitrogen flow.
After reacting at 00 ° C. for 6 hours, the free isocyanate value is 3.36.
% Prepolymer, and this is added to methyl ethyl ketone 8
15 parts were added to obtain a uniform urethane prepolymer solution. Next, 88.7 parts of isophoronediamine, 1224 parts of methyl ethyl ketone and 10 parts of isopropyl alcohol
In the presence of a mixture consisting of 19 parts, 2037 parts of the urethane prepolymer solution was added and reacted at 50 ° C. for 3 hours. The polyurethane resin solution thus obtained had a resin solid content concentration of 30% and a viscosity of 630 cP / 25 ° C.

Example 1 30 parts of titanium white (rutile type), 10 parts of toluene, 10 parts of methyl ethyl ketone, 10 parts of isopropyl alcohol,
32 parts of the polyurethane resin solution obtained in Production Example 1 and a terpene-based resin (trade name “YS Polystar PX125
0 "(produced by Yashara Chemical Co., Ltd.) in a 30% toluene solution), and each was kneaded with a paint shaker to prepare a white printing ink.

Examples 2 to 6 Example 1 was the same as Example 1 except that the amount of the polyurethane resin solution obtained in Production Example 1 or the type or amount of the terpene resin was changed as shown in Table 1. A white printing ink was prepared in the same manner as described above.

Comparative Example 1 A white printing ink was prepared in the same manner as in Example 1 except that the terpene resin was not used.

Comparative Example 2 In Example 1, chlorinated polypropylene (trade name “Supercron 813A”, manufactured by Nippon Paper Industries Co., Ltd., 30% toluene solution) was used in place of the terpene resin. In the same manner as in Example 1, a white printing ink was prepared.

[0031]

[Table 1]

In Table 1, 1) "YS Polystar PX125"
0 (trade name), 30% toluene solution of terpene resin manufactured by Yashara Chemical Co., Ltd .; 2) "YS Polystar T1"
45 (trade name), 30% toluene solution of terpene phenolic resin manufactured by Yashara Chemical Co., Ltd .; 3) "YS Polystar 2130 (trade name), Yashara Chemical Co., Ltd."
30% toluene solution of "terpene phenolic resin";
4) 30% of "YS polystar TO125 (trade name), aromatic modified terpene resin, manufactured by Yashara Chemical Co., Ltd."
Toluene solution; 5) 30 of “Supercron 813A (trade name), chlorinated polypropylene manufactured by Nippon Paper Industries Co., Ltd.”
% Toluene solution.

The white printing inks obtained in the above Examples and Comparative Examples were subjected to a corona discharge treatment OP having a thickness of 15 μm by a simple gravure printing machine equipped with a gravure plate having a depth of 30 μm.
P was printed on the discharge-treated surface of P, one surface of PET having a thickness of 11 μm, and the discharge-treated surface of corona discharge treatment NY having a thickness of 15 μm, and dried at 40 to 50 ° C. to obtain a printed film.

Adhesion: After leaving the printed matter for one day, a cellophane tape was stuck on the printed surface, and the appearance of the printed film when this was rapidly peeled was observed and evaluated according to the following criteria. Table 2 shows the evaluation results. A: No peeling occurred. 〇: 80% or more of the printed film remained on the film. Δ: 50 to 80% or more of the printed film remained on the film. X: 50% or less of the printed film remained on the film.

Corrosion of storage container:
It was stored in a petroleum can at room temperature, and after 3 months, the presence or absence of a corrosive state inside the container was confirmed. Table 2 shows the evaluation results.

[0036]

[Table 2]

Claims (3)

[Claims] 1. A printing ink binder comprising (1) a terpene resin and (2) a polyurethane resin as main components. 2. The weight ratio of (1) and (2) (1) / (2)
Is from 1/99 to 70/30. The binder for printing ink according to claim 1 or 2. 3. A printing ink using the printing ink binder according to claim 1.