JPH0812913A - Printing ink binder - Google Patents

Abstract

PURPOSE:To obtain a printing ink binder which gives a printing ink excellent in adhesion to various plastic films by mixing a chlorination product of a specific modified polyolefin with a urethane resin. CONSTITUTION:A chlorination product of a modified polyolefin is obtd. by reacting a low mol.wt. polyolefin modified with an unsatd. carboxylic acid or its anhydride (e.g. a maleic-anhydride-modified polypropylene) with a low mol.wt. diol (e.g. ethylene glycol) and/or a low mol.wt. compd. having hydroxyl and amino groups in the molecule (e.g. monoethanolamine) and chlorinating the resulting modified polyolefin with a chlorine gas, etc. A printing ink binder is obtd. by mixing the chlorination product with a urethane resin in a wt. ratio of the product to the resin of (3:97)-(50:50).

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a binder for printing inks. More specifically, various plastic films,
The present invention relates to a binder for printing ink suitable for printing a plastic sheet.

[0002]

2. Description of the Related Art In recent years, with the diversification and high functionality of packaging materials, it has been required to improve the design of materials such as plastic films and sheets used therein. Further, printing inks used for these materials are required to have higher performance. Above all, called flexible package,
Polyester film (PET), nylon film (NY) or stretched polypropylene film (OP
In the production of packaging materials that use plastic films as the base material such as P), after printing on the film material by methods such as gravure printing or flexographic printing, in order to improve the functionality such as heat sealability and airtightness of the packaging material. A polyethylene film or an unstretched polypropylene film is usually laminated by dry lamination or extrusion lamination. In particular, in the extrusion lamination process of coating with melted polyethylene or polypropylene, an anchor coating agent (AC agent) mainly composed of polyethyleneimine or polyisocyanate is usually used for the purpose of imparting adhesive strength to the ink layer. However, a processing method of directly laminating with molten polypropylene or the like without using an AC agent (direct laminating) is also performed. Direct lamination method is economically advantageous, but its suitability (adhesiveness)
Is mainly determined by the binder resin used in the printing ink. As a binder resin used in a conventional printing ink, a polyurethane resin having a wide range of adhesiveness to PET, NY, OPP and other base film is generally used. In addition, chlorinated polyolefins such as chlorinated polypropylene are used as those having direct laminating suitability.

[0003]

However, printing inks using a polyurethane resin as a binder have insufficient laminating suitability, especially direct laminating suitability, while inks using a chlorinated polyolefin as a binder are not suitable for OPP. Adheres well, but PET, NY
However, there is a problem that the substrate film that can be used is limited due to insufficient adhesiveness to the above. As a method for improving the adhesiveness with various plastic films, a resin composed of a polyurethane resin and a chlorinated polyolefin has been proposed (for example, JP-A-61-255937), but the adhesiveness is still insufficient. .

[0004]

Means for Solving the Problems As a result of intensive investigations by the present inventors, a binder for printing ink having sufficient adhesiveness to various plastic films and good direct laminating suitability was obtained. The present invention has been reached. That is, the present invention provides a modified low molecular weight polyolefin (a1) modified with an unsaturated carboxylic acid or an anhydride thereof.
And a low molecular weight diol (a2) and / or a low molecular weight compound (a3) having a hydroxyl group and an amino group in the molecule are reacted to form a chlorinated product (A) of a modified polyolefin and a urethane resin (B). It is a binder for printing ink.

(A1) in the present invention is obtained by reacting a low molecular weight polyolefin with an unsaturated carboxylic acid or an anhydride thereof.

Examples of the low molecular weight polyolefin include high density polyethylene, medium density polyethylene, low density polyethylene, polypropylene, polybutene, poly-4-methylpentene-1, a copolymer of ethylene and α-olefin, and ethylene-propylene rubber. , Ethylene-propylene-diene terpolymer (EPDM), ethylene-vinyl acetate copolymer, butyl rubber, butadiene rubber, low crystalline ethylene-propylene copolymer, propylene-butene copolymer, ethylene-vinyl ester copolymer Polymers, and combinations of two or more of these are included. Of these, polypropylene and a copolymer of propylene and α-olefin are preferable. The average molecular weight of the low molecular weight polyolefin is usually 1,000 to 50,000, preferably 2,000 to 20,000. These low molecular weight polyolefins may be obtained by a method of decomposing a high molecular weight polyolefin having the same constitutional unit by thermal decomposition, or may be obtained by a normal telomerization (α-olefin is homopolymerized or copolymerized). However, those obtained by a method of decomposing a high molecular weight polyolefin by thermal decomposition are preferable in that the content of terminal double bonds is large. The amount of double bonds in the low molecular weight polyolefin used is not particularly limited, but the amount is preferably 0.5 or more per 1000 carbon atoms.

The unsaturated carboxylic acid or its anhydride constituting (a1) includes acrylic acid, methacrylic acid, crotonic acid, maleic acid, cinnamic acid, itaconic acid, citraconic acid, fumaric acid; and maleic anhydride. Examples thereof include unsaturated carboxylic acid anhydrides such as itaconic anhydride and citraconic anhydride. Of these, maleic anhydride is particularly preferable.

The modification of the low molecular weight polyolefin with the unsaturated carboxylic acid or its anhydride can be carried out by a known method using a heat reaction or an organic peroxide. The (a
As an example of the production method of 1), a low-molecular-weight polyolefin is present in the presence or absence of a solvent such as an aromatic and / or chlorine system in an inert gas atmosphere, and a radical generating catalyst (peroxides such as di-tert-butyl). Peroxide, tert-butyl hydroperoxide, dicumyl peroxide, benzoyl peroxide, tert
-Butyl peroxide benzoate, etc .; Azonitriles such as azobisisobutyronitrile, azobisisovaleronitrile, azobisisopropionitrile, etc.)
In the presence or absence of the above, a method of obtaining the (a1) by heating (melting or dissolving) at 120 to 220 ° C. and reacting (grafting) an unsaturated carboxylic acid or an anhydride thereof can be mentioned.

The weight ratio of the (anhydrous) unsaturated carboxylic acid unit constituting (a1) is usually 0.5 to 15% by weight, preferably 1 to 10% by weight. P less than 0.5% by weight
Adhesion with ET film and NY film decreases,
If it exceeds 15% by weight, the adhesiveness to the OPP film is deteriorated.

Examples of the low-molecular diol (a2) to be reacted with this (a1) include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,4-butanediol, 3-methylpentanediol and 1,6-hexanediol. , Neopentyl glycol, bishydroxyethoxy benzene, and the like.

As the low molecular weight compound (a3) having a hydroxyl group and an amino group in the molecule, monoethanolamine, diethanolamine, 3-amino-1-propanol, 4
Examples include alkanolamines such as -amino-1-butanol, aminophenol, aminocresol, aminobenzyl alcohol, and aminophenylethyl alcohol. Of these, preferred is (a3),
Particularly preferred is monoethanolamine.

The method for chlorinating the above-mentioned modified polyolefin for obtaining (A) may be an ordinary method, for example, by dissolving it in a chlorine-based solvent such as carbon tetrachloride, chloroform or tetrachloroethylene under pressure or normal pressure, and 150
Examples include a method of injecting chlorine gas in the presence of the above-mentioned peroxide and ultraviolet rays at ℃.

The bound chlorine content of the chlorinated product (A) of the modified polyolefin is usually 5 to 50% by weight, preferably 1
It is 0 to 40% by weight. If the amount of bound chlorine is less than 5% by weight, the compatibility with the urethane resin (B) described later is poor and the mixture tends to be non-uniform, and if it exceeds 50% by weight, the adhesiveness is deteriorated.

In the present invention, the polyurethane resin (B) includes a polyol (b1) and an organic diisocyanate (b).
2) Polyurethane resins from and are mentioned. Examples of the polyol (b1) include polyether diol, polyester diol and polyolefin diol.

Examples of polyether diols include alkylene oxide adducts of low molecular weight diols and ring-opening (co) polymers of cyclic ethers. Examples of the low-molecular diols described above include aliphatic low-molecular diols [ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,4-
Or 1,3-butanediol, neopentyl glycol, pentanediol, 3-methylpentanediol, 1,6-hexanediol, 1,8-octamethylenediol, alkyl dialkanolamine, etc.], a low-molecular compound having a cyclic group Diols [for example, Japanese Patent Publication No. 4-14
No. 74, etc.] and mixtures of two or more thereof.

As the alkylene oxide, the alkylene oxide having 2 to 4 carbon atoms [ethylene oxide, propylene oxide, butylene oxide, etc.]
Is mentioned.

The above-mentioned ring-opening (co) polymer can be obtained by ring-opening polymerization or ring-opening copolymerization (block and / or random) of the alkylene oxide and / or cyclic ether (tetrahydrofuran etc.) exemplified in the above item. Some of them are listed.

Specific examples of the polyether diol include:
Polyethylene glycol, polypropylene glycol,
Polyoxyethylene-polyoxypropylene diol (block and / or random), polytetramethylene ether glycol, polytetramethylene ether-polyoxyethylene diol (block and / or random), polytetramethylene ether-polyoxypropylene diol (block) And / or random) and mixtures of two or more thereof.

As the polyester diol, a condensed polyester diol obtained by reacting a low molecular weight diol and / or a polyether diol having a molecular weight of 1000 or less with a dicarboxylic acid and / or a hydroxyl monocarboxylic acid, or a ring-opening polymerization of a lactone can be obtained. The polylactone diol etc. which are mentioned are mentioned.

Examples of the low molecular weight diol in the above include those exemplified in the above item. Molecular weight at 100
Examples of the polyether diol having a molecular weight of 0 or less include those having a molecular weight of 1000 or less among the above polyether diols, for example, polyethylene glycol, polytetramethylene ether glycol, polypropylene glycol, triethylene glycol and a mixture of two or more thereof.

As the dicarboxylic acid in the above, aliphatic dicarboxylic acids (succinic acid, adipic acid, sebacic acid,
Examples thereof include glutaric acid, azelaic acid, maleic acid and fumaric acid), polymerized fatty acid dibasic acid (such as dimer acid), aromatic dicarboxylic acid (such as terephthalic acid and isophthalic acid), and mixtures of two or more thereof. Examples of the lactone include ε-caprolactone and δ-valerolactone.

Specific examples of these polyester diols include polyethylene adipate, polybutylene adipate, polyhexamethylene adipate, polyneopentyl adipate, poly-3-methylpentane adipate,
Polyethylene propylene adipate, polyethylene butylene adipate, polybutylene hexamethylene adipate, polydiethylene adipate, poly (polytetramethylene ether) adipate, polyethylene azelate polyethylene sebacate, polybutylene azelate, polybutylene sebacate, polycaprolactone diol, polyvalero Lactone diols, polycarbonate diols and mixtures of two or more thereof.

Examples of polyolefin diols include diols obtained by polymerizing butadienes to introduce hydroxyl groups at both ends, and diols obtained by hydrogenating these. Specific examples of these polyolefin diols include polybutadiene diol, polyisoprene diol, hydrogenated polybutadiene diol, hydrogenated polyisoprene diol, and mixtures of two or more thereof.

When these polyols (b1) are used, they can be used alone or in combination of two or more.
When the oil resistance of the printed matter is required, it is preferable to use polyester diol in an amount of 50% by weight or more. (B1)
The average hydroxyl equivalent (average molecular weight per hydroxyl group) is usually 250 to 2500, preferably 350 to 2000.

The organic diisocyanate (b2) constituting (B) has a carbon number (excluding carbon in the NCO group).
2-12 aliphatic diisocyanates, alicyclic diisocyanates having 4-15 carbon atoms, araliphatic diisocyanates having 8-12 carbon atoms, aromatic diisocyanates having 6-20 carbon atoms and modified products of these organic diisocyanates (carbodiimide group , Uretdione group, uretoimine group, urea group, buret group and / or isocyanurate group-containing modified product).

Examples of such organic diisocyanates include ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HD
I), dodecamethylene diisocyanate, 2,2,4-
Trimethylhexane diisocyanate, lysine diisocyanate, 2,6-diisocyanate methylcaproate, bis (2-isocyanatoethyl) fumarate, bis (2-isocyanatoethyl) carbonate, 2-isocyanatoethyl-2,6-diisocyanato Aliphatic diisocyanates such as hexanoate; isophorone diisocyanate (IPDI), dicyclohexylmethane diisocyanate (hydrogenated MDI), cyclohexylene-1,4-
Alicyclic diisocyanates such as diisocyanate (CHI), methylcyclohexylene diisocyanate (hydrogenated TDI), bis (2-isocyanatoethyl) -4-cyclohexene-1-dicarboxylate; xylylene diisocyanate (XDI), tetramethylxylyl Aroaliphatic diisocyanates such as diisocyanate (TMXDI); aromatic diisocyanates such as tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI) and naphthalene diisocyanate; and mixtures of two or more thereof. Among these, preferred are aliphatic diisocyanates, alicyclic diisocyanates and araliphatic diisocyanates.

When producing the polyurethane resin (B), if necessary, a chain extender (b3) or a polymerization terminator (b4)
May be used. Examples of the chain extender (b3) include low molecular weight diols and diamines having an average molecular weight of less than 500. Examples of the low molecular weight diol include the diols mentioned as the raw materials for the polyester diol and its alkylene oxide low molar adducts (molecular weight less than 500).

As diamine, aliphatic diamine (ethylenediamine, hexamethylenediamine, 1,2-propylenediamine, 2,2,4-trimethylhexamethylenediamine, 2-hydroxyethylethylenediamine, di-2-hydroxyethylethylenediamine, etc.); Alicyclic diamine (isophoronediamine, 4,4'-diaminodicyclohexylmethane, isopropylidenedicyclohexyl-4,4'-diamine, 1,4-diaminocyclohexane, etc.); aromatic diamine (4,4'-diaminodiphenylmethane, etc.) Araliphatic diamines (such as xylenediamine); hydrazine or its derivatives (such as adipic acid dihydrazide); and mixtures of two or more thereof. When these (b3) are used, preferred are low molecular weight diols, alicyclic diamines and combinations thereof.

As the polymerization terminator (b4), monohydric alcohols such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol and isobutyl alcohol; monoethylamine, n-propylamine, n-butylamine , J-n
-Alkyl monoamines such as propylamine and di-n-butylamine; hydroxyl monoamines such as monoethanolamine and dietanololamine.

Examples of the method for producing the polyurethane resin (B) include a polyol (b1) and an organic diisocyanate (b).
2), if necessary, a one-shot method in which a chain extender (b3) and / or a polymerization terminator (b4) are reacted in a lump; or a urethane prepolymer having isocyanate groups at both ends is obtained from (b1) and an excess of (b2). It can be produced by any method of the prepolymer method of preparing and reacting the chain (b3) with the polymerization terminator (b4) if necessary.

In the production of the above urethane prepolymer in the prepolymer method, the organic diisocyanate (b
2) the isocyanate (NCO) group and the polyol (b
The equivalent ratio of the hydroxyl group of 1) is usually 1.1 to 5.0 / 1.0,
It is preferably 1.2 to 3.0 / 1.0. Further, a chain extender (b3) and a polymerization terminator (b4) which are optionally used
Is used in a substantially equivalent amount to the NCO groups of the prepolymer, for example, 1 isocyanate group of the prepolymer.
Chain extender (b3) and polymerization terminator (b
The total number of active hydrogen groups in 4) is usually 0.95 to 1.05 equivalent,
The amount is preferably 0.98 to 1.02 equivalent. The molecular end of the polyurethane resin (B) has an alkyl group, NCO
It may be a group, an OH group or an NH2 group, but is preferably an alkyl group.

Further, the above methods and can be carried out in the presence or absence of a solvent. Usable solvents include ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.), esters (ethyl acetate, propyl acetate, butyl acetate, etc.), ethers (tetrahydrofuran, etc.), aromatic hydrocarbons (toluene, xylene, etc.) ), Alcohols (methanol, ethanol,
Isopropyl alcohol, etc., polyhydric alcohol derivatives (ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, etc.), amides (dimethylformamide, etc.), sulfoxides (dimethyl sulfoxide, etc.), and mixed solvents of two or more of these. To be Of these, preferred are acetone, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, propyl acetate, butyl acetate, tetrahydrofuran, toluene, xylene, methanol, ethanol, isopropyl alcohol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether and these. Is a mixed solvent of two or more. The amount of solvent used is usually 100% by weight of the polyurethane resin (B) and the solvent.
/ 0 to 10/90, preferably 80/20 to 20/80
It is the amount that falls within the range of.

The content of (A) in the binder of the present invention is usually 3 to 3 based on the total weight of (A) and (B).
It is 50% by weight, preferably 5-40% by weight. (A)
If the content of P is less than 3% by weight, the adhesion to polyolefin is not sufficient, and if it exceeds 50% by weight, PET film or N
Adhesion with the Y film decreases.

The binder of the present invention can be used in the same manner as a conventional ink binder (for example, polyurethane resin). That is, a printing ink is produced by blending the binder of the present invention with a pigment and, if necessary, other ink resins, a solvent and an additive such as a pigment dispersant, and kneading the mixture using an ordinary ink producing device such as a ball mill. To use. Examples of the other resins mentioned above include polyamide, nitrocellulose, polyacrylates, polyvinyl chloride, copolymers of vinyl chloride and vinyl acetate, chlorinated polyolefin, polystyrene, butadiene rubber, epoxy resin and the like.

An example of the formulation of the printing ink using the binder of the present invention is shown below (% indicates% by weight). Binder (as solid content) of the present invention 10-20% Pigment 5-40% Other resins 0-10% Solvent (including solvent in binder) 40-75% Additives Appropriate amount

The binder of the present invention may be used for so-called one-pack type printing ink, but may also be used for two-pack type printing ink in combination with a polyisocyanate curing agent. Examples of the polyisocyanate-based curing agent in this case include an adduct synthesized from 1 mol of trimethylolpropane and 3 mol of 1,6-hexamethylene diisocyanate, tolylene diisocyanate or isophorone diisocyanate; 1,6-hexamethylene diisocyanate or isophorone. Isocyanurate group-containing trimer synthesized by cyclic trimerization of isocyanate group of diisocyanate; 1 mol of water and 1,6-
Partial burette reaction products synthesized from 3 mol of hexamethylene diisocyanate and mixtures of two or more thereof are preferred. The amount added is usually 0.5 to 1 for ink.
0% by weight. The method of printing with the printing ink using the binder of the present invention may be the same as the case of the conventional special gravure ink.

[0037]

The present invention will be further described with reference to the following examples, but the present invention is not limited thereto. In the following, "parts" means parts by weight, "%" means% by weight, and "ratio" means weight ratio.

Production Example 1 5 parts of maleic anhydride and 100 parts of a low molecular weight polypropylene obtained by a thermal degradation method having a number average molecular weight of 5000 and an amount of double bonds of 1.6 (per 1000 carbon atoms). It was dissolved in xylene and reacted in the presence of dicumyl peroxide to obtain a maleic anhydride-modified low molecular weight polypropylene having a maleic anhydride content of 4.5%. Furthermore, this maleic anhydride-modified low molecular weight polypropylene and monoethanolamine are reacted in xylene to remove the solvent,
A modified polyolefin was obtained. Then, 100 parts of this modified polyolefin was dissolved in 900 parts of tetrachloroethylene, and 60 parts of chlorine gas was aerated at 100 to 110 ° C. in the presence of ultraviolet rays. This chlorinated product was dropped into a large amount of methanol to precipitate a resin, which was further washed with methanol, filtered and dried. The bound chlorine content of this reaction product is 1
It was 8%. 20 parts of this reaction product is dissolved in 80 parts of toluene to prepare a chlorinated chloride solution of modified polypropylene (P-1).
I got

Production Example 2 A reaction product having a combined chlorine content of 27% was obtained in the same manner as in Production Example 1 except that the chlorine gas aeration rate was changed to 100 parts. 20 parts of this reaction product was dissolved in 80 parts of toluene to obtain a chlorinated product solution (P-2) of modified polypropylene.

Production Example 3 100 parts of polybutylene adipate (molecular weight 2000),
100 parts of poly-3-methylpentane adipate diol (molecular weight 2000), 1,4-butane diol 12.6
Parts, 55.5 parts of isophorone diisocyanate, 0.05 parts of dioctyltin dilaurate and 403 parts of toluene were charged into a reaction vessel and reacted at 110 ° C. for 8 hours. Then, after cooling to 70 ° C., di-n-butylamine 1.2
Parts were added and the mixture was further stirred for 1 hour to complete the reaction, and a polyurethane resin solution (U-1) having a solid content of 40% and a viscosity of 45 poise / 25 ° C. was obtained.

Production Example 4 Polycaprolactone diol (molecular weight 2000) 200
Parts, 7.2 parts of neopentyl glycol, 48.3 parts of isophorone diisocyanate and 0.05 parts of dioctyltin dilaurate were charged in a reaction vessel and reacted at 100 ° C. for 8 hours to obtain a urethane prepolymer having an NCO% of 1.55. It was Next, after adding 388 parts of toluene and dissolving uniformly,
A mixture of 6.7 parts of isophoronediamine, 3.1 parts of di-n-butylamine and 10 parts of isopropanol was added to a toluene solution of the urethane prepolymer, and 5
The reaction was carried out at 0 ° C for 1 hour to obtain a polyurethane resin solution (U-2) having a solid content of 40% and a viscosity of 52 poise / 25 ° C.

Example 1 To 200 parts of (P-1) obtained in Production Example 1, 200 parts of (U-1) obtained in Production Example 3 was added and mixed with stirring to obtain a solid content of 30% and a viscosity of 5 A uniform resin solution (a) of 0.2 poise / 25 ° C. was obtained.

Example 2 To 100 parts of (P-1) obtained in Production Example 1, 300 parts of (U-1) obtained in Production Example 3 and 67 parts of toluene were added and mixed by stirring to obtain a solid. Min 30%, viscosity 8.0 poise / 2
A uniform resin solution (b) at 5 ° C. was obtained.

Example 3 To 200 parts of (P-2) obtained in Production Example 2, 200 parts of (U-2) obtained in Production Example 4 was added and mixed with stirring to obtain a solid content of 30% and a viscosity of 6%. A uniform resin solution (C) at 0.0 poise / 25 ° C. was obtained.

Example 4 To 100 parts of (P-2) obtained in Production Example 2, 300 parts of (U-2) obtained in Production Example 4 and 67 parts of toluene were added and mixed by stirring to obtain a solid. Min 30%, viscosity 4.5 poise / 2
A uniform resin solution (5) at 5 ° C. was obtained.

Performance Test Example Using the resin solutions (a) to (d) obtained in Examples 1 to 4 as binder solutions, printing inks were prepared according to the following formulation. The above materials were placed in a steel can having an internal volume of 500 ml, and kneaded with a paint conditioner (manufactured by Red Devil Co.) for 1 hour to prepare an ink. The obtained printing ink was used to print on a PET film, NY film and OPP film with a gravure proofing machine. The following performance test was performed on the obtained printed matter. Table 1 shows the results.

Performance test items and test method Adhesiveness: Nichiban Cello tape (12 mm width) is attached to the print surface, and one end of this Nichiban Cello tape is rapidly peeled in a direction perpendicular to the print surface to be in a state of the print surface. Was observed. Blocking resistance: Printed surface and non-printed surface are overlapped, and the temperature is 40 ° C. and the humidity is 60% RH, 1.0 Kg / cm ²
Was applied and after 24 hours, it was peeled off and the surface condition was observed. Oil resistance: The surface condition after immersing the printed matter in rapeseed oil at 25 ° C. for 24 hours was observed. Direct Lamination Suitability: O
An untreated low-density polyethylene film is overlaid on the ink side of the PP print, and heat fusion is applied under pressure at 200 ° C × 1 Kg / cm ² using a heat sealer (manufactured by Toyo Seiki Co., Ltd.), and the T peel strength after 1 day It was measured. The criteria for judging the above test results are as follows. ◎: Very good, ○: Good, △: Slightly bad, ×: Bad

Comparative Example 1 Ink preparation, printing and performance test were conducted in the same manner as in Example 1 except that only the polyurethane resin (U-1) obtained in Production Example 3 was used as the binder resin. Table 1 shows the results.

Comparative Example 2 Ink preparation, printing and performance tests were carried out in the same manner as in Example 1 except that only the modified polypropylene chlorinated solution (P-1) obtained in Production Example 1 was used as the binder resin. went. Table 1 shows the results.

[0050]

[Table 1]

[0051]

The printing ink using the binder of the present invention has excellent properties such as good adhesion to a wide range of plastic films such as polyolefin films, polyester films and nylon films, and suitability for direct laminating. Compared with binder resin, ink can be designed for a wide range of purposes. Further, since the binder of the present invention has excellent adhesiveness to various plastics, it can be applied as a coating primer or paint for various plastic molded products.

Claims (5)

[Claims] 1. An acid-modified low-molecular-weight polyolefin (a1) modified with an unsaturated carboxylic acid or an anhydride thereof, a low-molecular diol (a2) and / or a low-molecular compound having a hydroxyl group and an amino group in the molecule ( A binder for printing ink comprising a chlorinated product (A) of a modified polyolefin obtained by reacting a3) and a urethane resin (B). 2. The binder according to claim 1, wherein the polyolefin before modification constituting (a1) is a heat-reduced low molecular weight polyolefin. 3. The binder according to claim 1, wherein the weight ratio of the unsaturated carboxylic acid or its anhydride constituting (a1) is 0.5 to 15% by weight. 4. The binder according to claim 1, wherein the content of bound chlorine in (A) is 5 to 50% by weight. 5. The binder according to claim 1, wherein the content of (A) is 3 to 50% by weight based on the total weight of (A) and (B).