JPH083069B2 - Binder for printing ink - Google Patents

Description

TECHNICAL FIELD The present invention relates to a printing ink binder.

[Prior Art] Conventionally, polyurethane resins have been used as binders for inks for printing on various plastic films such as polypropylene, polyester and nylon (for example, Japanese Examined Patent Publication No. 54-22125 and Japanese Unexamined Patent Publication No. 54-36960). Polyurethane resin generally has excellent adhesiveness and oil resistance, but it is inferior in heat blocking resistance and resolubility. On the other hand, acrylic resins are known as binders for inks that have excellent heat blocking resistance and resolubility, and are widely used mainly for printing paper.
Poor adhesion to various plastic films other than polyvinyl chloride.

In addition, a method of mixing and using a polyurethane resin and an acrylic resin has been proposed for the purpose of complementing the respective drawbacks of the polyurethane resin and the acrylic resin (for example, JP-A-63-57680).

[Problems to be Solved by the Invention] However, in general, if the polyurethane resin and the acrylic resin are simply mixed, the compatibility is poor, and a stable ink cannot be obtained. There is a problem that it is necessary to introduce a group and the mixing ratio of both is also limited.

[Means for Solving the Problems] The present inventors aim to obtain a binder for a printing ink that has good adhesion to various plastic films and is excellent in heat blocking resistance and resolubility. As a result of intensive studies, the present invention has been reached.

That is, the present invention relates to the polyol (a), the polyisocyanate (b) and the general formula (In the formula, R is H or CH ₃ , and Y is NH or O.), or the compound (c) and the general formula (c). (In the formula, R is H or CH ₃ , X is an alkylene group having 2 to 4 carbon atoms which may have a substituent, m is an integer of 1 to 5, n is an integer of 0 to 5, and p is 4 or In the presence of a polyurethane resin (A) comprising a compound (c ′) represented by the formula (5) and optionally a chain extender (d) and / or a polymerization terminator (e). A binder for a printing ink, comprising a modified polyurethane resin soluble in an organic solvent obtained by polymerizing a monomer (B).

In the general formula (2), examples of the alkylene group having 2 to 4 carbon atoms for X include ethylene, propylene and butylene groups. Phenyl substituents, halogen (C
l, Br, etc.) substituents. The alkylene group having a substituent is a styrene group, an α-methylstyrene group,
An epichloro group is mentioned.

m is preferably 1-2. n is preferably 0 or 1. p is preferably 5.

Specific examples of the compound (c ′) represented by the general formula (2) include 2-hydroxyethyl (meth) acrylate and 2
-Hydroxypropyl (meth) acrylate, ε-caprolactone-2-hydroxyethyl (meth) acrylate adduct, γ-valerolactone-2-hydroxyethyl (meth) acrylate adduct, and the like.

Specific examples of the compound (c) represented by the general formula (1) are allylamine and allyl alcohol.

Examples of the polyol (a) used in the present invention include polyether diol and polyester diol.

Low molecular weight glycols such as polyether diol [ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,4- and 1,3-
Butanediol, neopentyl glycol, 3-methylpentanediol, 1,6-hexanediol, 1,8-octamethylenediol, alkyl dialkanolamines;
Low molecular weight diols having a cyclic group [for example, Japanese Patent Publication No.
No. 4 publication: bis (hydroxymethyl) cyclohexane, m- and p-xylylene glycol, bis (hydroxyethylbenzene, 1,4-bis (2-hydroxyethoxy) benzene, 4,4'-bis (2- Hydroxyethoxy) -diphenylpropane (bisphenol A
Ethylene oxide adduct), etc.] and mixtures of two or more thereof, etc.] (Alkylene oxides having 2 to 4 carbon atoms: ethylene oxide, propylene oxide, 1,2-, 2,3- and 1,3-butylene Oxides) adducts; those obtained by ring-opening polymerization or ring-opening copolymerization (block and / or random) of alkylene oxides and / or cyclic ethers (such as tetrahydrofuran), for example polyethylene glycol, polypropylene glycol, polyethylene-polypropylene ( (Block and / or random) glycol, polytetramethylene ether glycol, polytetramethylene-ethylene (block and / or random) glycol, polytetramethylene-propylene (block and / or random) glycol, polyhexamethyi Emissions ether glycol, polyoctamethylene ether glycol and mixtures of two or more thereof.

The polyester diol includes a condensed polyester diol obtained by reacting a low molecular diol and / or a polyether diol having a molecular weight of 1,000 or less with a dicarboxylic acid, a polylactone diol obtained by ring-opening polymerization of a lactone, and the like. Examples of the low molecular weight diol include ethylene glycol diethylene glycol, propylene glycol, dipropylene glycol, 1,3- and 1,4-butanediol, neopentyl glycol, 3-methylpentanediol, 1,6-hexanediol, 1,8- Octamethylene diol, alkyl dialkanol amine; low molecular weight diols having cyclic groups [eg Japanese Patent Publication No. 45-147
No. 4 publication: bis (hydroxymethyl) cyclohexane, m- and p-xylylene glycol, bis (hydroxyethylbenzene, 1,4-bis (2-hydroxyethoxy) benzene, 4,4'-bis (2- Hydroxyethoxy) -diphenylpropane (bisphenol A
Ethylene oxide adduct) and the like] and mixtures of two or more thereof.

Examples of the polyether diol having a molecular weight of 1000 or less include the above-mentioned polyether diols such as polyethylene glycol, polytetramethylene ether glycol, polypropylene glycol, triethylene glycol; and a mixture of two or more thereof. As the dicarboxylic acid, an aliphatic dicarboxylic acid (succinic acid, adipic acid,
Sebacic acid, glutaric acid, azelaic acid, maleic acid,
Fumaric acid, etc., aromatic dicarboxylic acid (terephthalic acid,
Isophthalic acid and the like) and mixtures of two or more thereof, and examples of the lactone include ε-caprolactone and γ-valerolactone.

Polyester diols can be prepared by a conventional method, for example, by using a low molecular weight diol and / or a polyether diol having a molecular weight of 1,000 or less, a dicarboxylic acid or an ester-forming derivative thereof [for example, an anhydride (maleic anhydride, phthalic anhydride, etc.), a lower ester (terephthalate). Acid dimethyl etc.), halide etc.] or its anhydride and alkylene oxide (eg ethylene oxide and / or propylene oxide) are reacted (condensed), or an initiator (low molecular diol and / or polyether having a molecular weight of 1000 or less) It can be produced by adding a lactone to (diol).

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, and polybutylene hexamethylene adipate. Examples include diethylene adipate, poly (polytetramethylene ether) adipate, polyethylene azelate, polyethylene sebacate, polybutylene azelate, polybutylene sebacate, polycaprolactone diol, polyvalerolactone diol, and mixtures of two or more thereof. .

The average molecular weight of these polymeric diols (as measured by hydroxyl value) is usually 200 to 5000, preferably 300 to 4000.

When producing the polyurethane resin (A), a low molecular weight polyfunctional active hydrogen compound may be used as the chain extender (d) if necessary.

Examples of the low-molecular polyfunctional active hydrogen compound include the low-molecular glycols and the alkylene oxide low-mol adducts (molecular weight 20
Less than 0), aliphatic diamine (ethylenediamine, hexamethylenediamine, etc.), alicyclic diamine (isophoronediamine, 4,4′-dicyclohexylmethanediamine, etc.), aromatic diamine (4,4′-diaminodiphenylmethane, etc.), aromatic Aliphatic diamines (such as xylenediamine), alkanoldiamines (such as ethanolethylenediamine), hydrazine, dihydrazides (such as adipic acid dihydrazide), and mixtures of two or more thereof. Of these, preferred are low molecular weight glycols, alicyclic diamines and mixtures of two or more thereof.

Furthermore, if necessary, a monovalent low-molecular alcohol (methanol, butanol, cyclohexanol, etc.) as a polymerization terminator (e), a monovalent alkylamine (mono- and di-
Methylamine, mono- and di-butylamine, etc.), alkanolamines (mono- and di-ethanolamine, etc.) and the like may be used.

Polyisocyanate (b) used in the present invention
As, the number of carbon atoms (excluding carbon atoms in the NCO group) is 2 to 12, aliphatic polyisocyanate having 4 to 15 carbon atoms, alicyclic polyisocyanate having 8 to 12 carbon atoms, araliphatic polyisocyanate having 8 to 12 carbon atoms, and 6 to carbon atoms. Aromatic polyisocyanates of 20 and modified products of these polyisocyanates (carbodiimide group, uretdione group, uretoimine group, urea group, buret group and / or isocyanurate group-containing modified product, etc.) can be used. Such polyisocyanates include ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HD
I), dodecamethylene diisocyanate, 1,6,11-undecane triisocyanate, 2,2,4-trimethylhexane diisocyanate, lysine diisocyanate, 2,6-
Diisocyanatomethylcaproate, bis (2-isocyanatoethyl) fumarate, bis (2-isocyanatoethyl) carbonate, 2-isocyanatoethyl-2,6-
Diisocyanato hexanoate; isophorone diisocyanate (IPDI), dicyclohexylmethane diisocyanate (hydrogenated MDI), cyclohexylene diisocyanate, methylcyclohexylene diisocyanate (hydrogenated TD
I), bis (2-isocyanatoethyl) 4-cyclohexene-1,2-dicarboxylate; xylylene diisocyanate (XDI), tetramethyl xylylene diisocyanate (TMXDI), diethylbenzene diisocyanate;
Water-modified HDI, trimerized IPDI, etc .; Tolylene diisocyanate (TDI), crude TDI, diphenylmethane diisocyanate (MDI), polyphenylmethane polyisocyanate (crude MDI), modified MDI (carbodiimide modified MDI)
Etc.), naphthylene diisocyanate; and mixtures of two or more thereof. Among these, aliphatic diisocyanates, alicyclic diisocyanates and araliphatic diisocyanates are preferable in terms of solubility.

When producing the polyurethane resin (A) in the present invention, the amount of the low molecular weight polyfunctional active hydrogen compound as the chain extender (d) is usually 50% by weight or less, preferably 30% by weight or less based on the polyol (a). Is.

The ratio of the polyol (a) and the chain extender (d) to the polyisocyanate (b) is usually NCO / active hydrogen equivalent of 1.05 to
It is 2.0, preferably 1.1 to 1.8.

The total amount of the compound (c) represented by the general formula (1), or the compound (c ') represented by the formula (c) and the general formula (2) is such that the polyol (a) and the chain extender (d). And usually 0.3% to 3 relative to the total weight of polyisocyanate (b)
It is 0%, preferably 0.5 to 20%.

The amount of the polymerization terminator (e) is the sum of the terminator (e): the compound (c) represented by the general formula (1) and, if necessary, the compound (c ′) represented by the general formula (2). The weight ratio is usually (0: 100) ~ (90:10), preferably (0: 100) ~ (80: 2).
It is an amount in the range of 0).

A polyol (a), a chain extender (d), a compound (c) represented by the general formula (1), and optionally a compound (c ') represented by the general formula (2), and a polymerization terminator (e). The ratio of the active hydrogen-containing compound consisting of the polyisocyanate (b) is such that the NCO / active hydrogen equivalent is usually 0.8 to 1.2, preferably 0.9.
~ 1.1.

In the production of the polyurethane resin (A) in the present invention, the polyol (a), the polyisocyanate (b) and, if necessary, the chain extender (d) are reacted and then represented by the general formula (1) having an active hydrogen group. (C) and optionally the compound (c ′) represented by the general formula (2) are reacted to a position where the compound does not substantially contain an NCO group, or a reaction is performed in a lump. It may be a method.

The reaction temperature during production is usually 20 to 150 ° C, preferably 50
~ 120 ° C.

In order to accelerate the reaction, amine-based catalysts (triethylamine, N-ethylmorpholine, triethylenediamine, etc.) and tin-based catalysts (trimethyltin laurate, dibutyltin dilaurate, etc.) used in ordinary urethane reactions may be used. In order to prevent gelation due to radical polymerization during the reaction of the compound (c) represented by the general formula (1) or the compound (c ') represented by the formula (c) and the general formula (2). 20 to 2000 ppm of hydroquinone, hydroquinone monomethyl ether, based on the reaction solid content,
It is preferable to add a polymerization inhibitor such as p-methoxyphenol or p-benzoquinone.

The polyurethane resin (A) is produced in the presence or absence of a solvent. Examples of the solvent used include ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.), esters (ethyl 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 thereof. To be Of these, preferably acetone, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, butyl acetate, tetrahydrofuran, toluene, xylene, methanol, ethanol,
Isopropyl alcohol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, and a mixed solvent of two or more of these.

The amount of the solvent used is such that the weight ratio of the polyurethane resin (A) to the solvent is in the range of 100/0 to 10/90, preferably 80/20 to 20/80.

In the present invention, the desired modified polyurethane resin is obtained by polymerizing the ethylenically unsaturated monomer (B) in the presence of the polyurethane resin (A).

The following are mentioned as an ethylenically unsaturated monomer (B) used.

(A) (Meth) acrylic acid and its derivatives: (meth) acrylonitrile; (meth) acrylic acid and salts thereof; alkyl (meth) acrylates such as methyl (meth) acrylate and n-butyl (meth) acrylate. The number of carbon atoms in the group is usually 1 to 20, preferably 1
~ 10) ester; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate,
(meth) acrylic acid hydroxyalkyl (the carbon number of the alkyl group is usually 2 to 4) esters such as ε-caprolactone-2-hydroxyethyl (meth) acrylate and lactone adducts thereof; ) Acrylate; (meth) acrylic acid amide and the like.

(B) Aromatic vinyl hydrocarbon monomer: Styrene, α-methylstyrene, vinyltoluene and the like.

(C) Vinyl ester monomer: vinyl acetate, vinyl propionate, etc.

(D) Vinyl ether monomer: methyl vinyl ether, butyl vinyl ether, etc.

Among these, preferred are the monomers (a) and (b), which may be used alone or in combination of two or more.

The modified polyurethane resin composition in the present invention is usually prepared by adding the ethylenically unsaturated monomer (B) in the presence of the polyurethane resin (A) under an inert gas atmosphere and in the presence of a polymerization catalyst (radical generator). It can be produced by radical polymerization according to the above method. In this case, the weight ratio of the polyurethane resin (A) (solid content) and the ethylenically unsaturated monomer (B) is usually 95/5 to 5/95, preferably 90/10 to 10/90. If the polyurethane resin (A) exceeds 95, the heat blocking resistance and redissolvability of the ink are deteriorated, and if it is less than 5, sufficient adhesion to various plastic films cannot be obtained, which is not preferable.

As the polymerization catalyst (radical generator) used in the above-mentioned polymerization reaction, an azo compound (for example, azobisisobutyronitrile) and an organic peroxide (for example, benzoyl peroxide) are suitable. The amount used is not particularly limited, but is usually 0.05 to 10% by weight, preferably 0.1 to 5% by weight based on the total amount of the ethylenically unsaturated monomer (B). The polymerization temperature is usually 50 to 170 ° C., preferably 70 to 150 ° C., and the polymerization time is usually 1 to 24 hours. A known chain transfer agent (for example, dodecyl mercaptan) can be used for the purpose of adjusting the degree of polymerization of the polymer.

The above polymerization reaction is carried out in the presence or absence of a solvent. As the solvent, those used in the production of the polyurethane resin (A) can be used.

The amount of the solvent used is such that the weight ratio of the modified polyurethane resin composition to the solvent is in the range of 100/0 to 10/90, preferably 80/20 to 20/80.

The viscosity of the modified polyurethane resin composition obtained by the above is usually 50 to 500,000, preferably 100 to 100,000 (cps / 2
0 ° C) and the molecular weight (weight average molecular weight) is usually 2,000-
It is 200,000, preferably 5,000 to 150,000.

The modified polyurethane resin composition thus obtained has excellent properties as a binder for printing inks, especially as a binder for special gravure inks.

Further, the binder for ink of the present invention can be used in the same manner as in the case of the conventional binder for ink (for example, polyurethane resin). That is, a printing ink is produced by using a binder of the present invention with a pigment and, if necessary, other additives such as a resin, a solvent and a pigment dispersant, and kneading the mixture with an ordinary ink producing device such as a ball mill. To do.

Examples of the other resins mentioned above include polyamide, nitrocellulose, polyacrylates, polyvinyl chloride, copolymers of vinyl chloride and vinyl acetate, styrene, butadiene rubber, and epoxy resins.

The formulation examples of the printing ink using the ink binder of the present invention are as follows (% indicates% by weight).

Binder of the present invention (per solid content) 10 to 20% Pigment 5 to 40% Other resins 0 to 10% Solvent 40 to 75% Additive Appropriate amount As a target to which the printing ink using the binder of the present invention is applied, Polyester film, nylon film, polypropylene film, polyvinyl chloride film and the like are suitable.

The binder of the present invention may be used for a so-called one-component printing ink, but may also be used for a two-component printing ink in combination with a polyisocyanate curing agent. In this case, as the polyisocyanate curing agent,
For example, an adduct synthesized from 1 mol of trimethylolpropane and 3 mol of 1,6-hexamethylene diisocyanate, tolylene diisocyanate or isophorone diisocyanate; synthesized by cyclic trimerization of the isocyanate group of 1,6-hexamethylene diisocyanate or isophorone diisocyanate. Preferred is an isocyanurate group-containing trimer; a partial burette reaction product synthesized from 1 mol of water and 3 mol of 1,6-hexamethylene diisocyanate, and a mixture of two or more thereof. When used as a two-component printing ink, the amount of the polyisocyanate-based curing agent added is usually 0.5 to 10% by weight based on the ink.

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.

[Examples] Hereinafter, the present invention will be further described with reference to Examples, but the present invention is not limited thereto. In the following, parts and% indicate parts by weight and% by weight, respectively.

(Synthesis Example of Polyurethane Resin) Synthesis Example 1 Polybutylene adipate 2000 having a molecular weight of 2000 in a three-neck flask having a stirrer, a reflux condenser and a nitrogen blowing tube.
Parts, 135 parts of 1,4-butanediol and 666 parts of isophorone diisocyanate were charged, heated to 100 to 120 ° C. and reacted for 6 hours, then cooled to 80 ° C., toluene 1245 parts, 2-hydroxyethyl methacrylate 68 parts, butanol. 37 parts, hydroquinone 0.1 part, and dibutyltin dilaurate 0.3 part were charged, the reaction was carried out at a temperature of 80 to 90 ° C., and the reaction was completed when the free isocyanate group concentration became about 0.05% or less. 1661 parts of toluene was added to form a uniform solution.

A polyurethane solution having a solid content of 50% and a viscosity of 16,000 cps / 20 ° C. was obtained. This is A-1.

Synthesis Example 2 1000 parts of polytetramethylene glycol having a molecular weight of 1000,
4,4'-Dicyclohexylmethane diisocyanate 316
Parts, toluene 606 parts, ε-caprolactone-2-hydroxyethyl methacrylate 100 parts, hydroquinone 0.1 parts and dibutyltin dilaurate 0.15 parts, and a temperature of 80-
The reaction is carried out at 90 ° C and the free isocyanate group concentration is about 0.
The reaction was completed when it became less than 05%. toluene
808 parts was added to make a uniform solution.

A polyurethane solution having a solid content of 50% and a viscosity of 20,000 cps / 20 ° C. was obtained. This is A-2.

Synthesis example 3 1000 parts of polycaprolactone diol having a molecular weight of 500 and 500 parts of isophorone diisocyanate were charged and the temperature was 100 to 120 ° C.
After heating to room temperature and reacting for 6 hours, cool to 40 ° C and add toluene.
After charging 1262 parts and 280 parts of isopropanol and dissolving them uniformly, 15 parts of allylamine and diethanolamine were added.
25 parts were charged and reacted at a temperature of 30 to 40 ° C. for 1 hour, and when the free isocyanate group concentration became about 0.05% or less,
The reaction was complete.

A polyurethane solution having a solid content of 50% and a viscosity of 3,000 cps / 20 ° C. was obtained. This is A-3.

Synthesis Example 4 (Comparative) 1000 parts of polybutylene adipate having a molecular weight of 2000, 1,4-
Butanediol 67 parts and isophorone diisocyanate 33
Charge 3 parts and heat to 100-120 ℃ and react for 6 hours, then
After cooling to 00 ° C, 616 parts of toluene, 37 parts of butanol and 0.15 part of dibutyltin dilaurate were charged and the reaction was carried out at a temperature of 90 to 100 ° C, and the reaction was completed when the free isocyanate group concentration became about 0.05% or less. . Toluene (821 parts) was added to obtain a uniform solution.

A polyurethane solution having a solid content of 50% and a viscosity of 12,000 cps / 20 ° C. was obtained. This is A-4.

Example 1 (Reference Example) Obtained in Synthesis Example 1 in a four-necked flask having a stirrer, a reflux condenser, a nitrogen blowing tube, and a dropping funnel (A-1) 600
And 165 parts of toluene are charged and the temperature is raised to 90 to 100 ° C. while blowing nitrogen at a rate of 10 ml / min. In a flask maintained at a temperature of 90 to 100 ° C, 180 parts of methyl methacrylate, 10 parts of methacrylic acid and 10 parts of 2-hydroxyethyl methacrylate were added.
Part, azobisisobutyronitrile 1.4 parts and toluene 50
Part of the mixed solution was added dropwise over 3 hours to carry out a polymerization reaction.
1 hour after the end of dropping, azobisisobutyronitrile 1.4
A mixture of 100 parts of toluene and 100 parts of toluene was added dropwise over 3 hours for aging to complete the reaction.

Solid content 45%, viscosity 15,000cps / 20 ℃, molecular weight about 35,000
A uniform and transparent solution of the modified polyurethane resin composition having a weight average molecular weight of about 60% in the solid content of the polyurethane resin was obtained.

Example 2 (Reference Example) A four-necked flask equipped with a stirrer, a reflux condenser, a nitrogen blowing tube, and a dropping funnel was obtained in Synthesis Example 1 (A-1) 200.
And 216 parts of toluene are charged and the temperature is raised to 90 to 100 ° C. while blowing nitrogen at a rate of 10 ml / min. Mix 180 parts of methyl methacrylate, 190 parts of butyl methacrylate, 10 parts of methacrylic acid, 20 parts of 2-hydroxyethyl methacrylate, 4.0 parts of azobisisobutyronitrile and 100 parts of toluene in a flask maintained at a temperature of 90 to 100 ° C. The liquid was added dropwise over 3 hours to carry out a polymerization reaction. One hour after the completion of the dropping, a mixed solution of 2.8 parts of azobisisobutyronitrile and 200 parts of toluene was added dropwise over 3 hours for aging to complete the reaction.

Solid content 45%, viscosity 10,000cps / 20 ℃, molecular weight about 28,000,
A homogeneous transparent solution of the modified polyurethane resin composition having a polyurethane resin content of about 20% in the solid content was obtained.

Example 3 (Reference Example) A polymerization reaction was performed in the same manner as in Example 2 except that 200 parts of (A-2) obtained in Synthesis Example 2 was used.

Solid content 45%, viscosity 30,000cps / 20 ℃, molecular weight about 40,000,
A uniform transparent solution of the modified polyurethane resin composition having a polyurethane resin content of about 20% in the solid content was obtained.

Example 4 (Example) A polymerization reaction was performed in the same manner as in Example 1 except that 600 parts of (A-3) obtained in Synthesis Example 3 was used.

Solid content 45%, viscosity 7,000cps / 20 ℃, molecular weight about 30,000,
A homogeneous transparent solution of the modified polyurethane resin composition having a polyurethane resin content of about 60% in the solid content was obtained.

Comparative Example 1 In Example 1, the polymerization reaction was carried out without using (A-1),
45% solids consisting only of methacrylate, viscosity 11,000 cp
A transparent polymer solution having a molecular weight of about 30,000 was obtained at s / 20 ° C.

Comparative Example 2 A polymerization reaction was performed in the same manner as in Example 1 except that 600 parts of (A-4) obtained in Synthesis Example 4 was used.

Solid content 45%, viscosity 3,000cps / 20 ℃, molecular weight about 25,000,
A transparent solution of a polyurethane mixed resin having a polyurethane content of about 60% in the solid content was obtained.

Comparative Example 3 Synthesis Example 4 was added to the acrylic polymer solution obtained in Comparative Example 1.
The polyurethane solution (A-4) obtained in step (A-4) was added in an amount such that the solid content ratio of (A-4) was 60%, and toluene was added to solid content 45
% Was prepared. The appearance of the resulting solution was opaque.

Comparative Example 4 100 parts of (A-4) obtained in Synthesis Example 4 was mixed with 11 parts of toluene to obtain a polyurethane resin solution having a solid content of 45%.

Example 5 (Reference Example) Synthesis Example 1 was added to the modified polyurethane resin solution obtained in Example 1.
The urethane polymer solution (A-4) obtained in Example 2 and the acrylic polymer solution obtained in Comparative Example 2 had a solid content ratio of
The amount of 1/1/1 was mixed and mixed. The resulting solution was homogeneous and transparent.

Using the resin solutions of Examples 1 to 5 and Comparative Examples 1 to 4 as binder solutions, printing inks were prepared according to the following formulations.

Binder solution 50 parts Pigment (titanium oxide) 40 parts MEK 30 parts Toluene 10 parts IPA 20 parts Ceramic balls 100 parts Total 250 parts The above raw materials are placed in a steel can with an internal volume of 500 ml and a paint conditioner (made by Red Devil Co. ) For 1 hour to prepare a printing ink.

Using the obtained printing ink, a polyester film (abbreviated as PET) and nylon film (N
Y), a surface-treated stretched polypropylene film (abbreviated as OPP) and a hard polyvinyl chloride film (abbreviated as PVC) were printed to obtain a printed matter.

The obtained printed matter was tested as follows.
A result of 1 was obtained.

(1) Adhesiveness Nichiban Cello tape (12 mm width) was attached to the printed surface, and one end of this Nichiban Cello tape was rapidly peeled in a direction perpendicular to the printed surface to observe the state of the printed surface.

(2) Blocking resistance The printed surface and non-printed surface are overlaid, and the temperature is 40 ° C and the humidity is 60% RH.
A load of 1.0 Kg / cm ² was applied in the sample, and after 24 hours, it was peeled off and the surface condition was observed.

(3) Oil resistance The printed matter was immersed in rapeseed oil at 25 ° C for 24 hours, and the surface condition was observed.

(4) Heat resistance Combine the printed surface with the aluminum foil and heat it with a heat sealer.
It was heat-sealed at 80 ° C. for 1 kg / cm ² × 1 second, peeled off, and the surface condition was observed.

(5) Re-dissolvability of ink The ink was applied to a glass plate, air-dried for 10 seconds, and then immersed in a solvent (toluene / MEK / isopropanol = 1/1/1) to observe the re-solubility.

(6) Ink stability The obtained ink was allowed to stand at 20 ° C for 1 day, and the appearance of the ink was observed.

 The criteria for judging each test result are: ⊚ extremely good, ◯ good, Δ a little bad, and × bad.

[Effects of the Invention] The printing ink binder of the present invention has the advantages of both a polyurethane resin and a polyacrylic resin, and has very good solution stability, so it can be applied to a wide range of printing targets. Moreover, since the composition and ratio of the polyurethane component and the polyacrylic component can be arbitrarily selected, it is possible to design the ink according to the purpose of use.

Claims (2)

[Claims] 1. A polyol (a), a polyisocyanate (b) and a general formula (In the formula, R is H or CH ₃ , and Y is NH or O.), or the compound (c) and the general formula (c). (In the formula, R is H or CH ₃ , X is an alkylene group having 2 to 4 carbon atoms which may have a substituent, m is an integer of 1 to 5, n is an integer of 0 to 5, and p is 4 or In the presence of a polyurethane resin (A) comprising a compound (c ′) represented by the formula (5) and optionally a chain extender (d) and / or a polymerization terminator (e). A binder for a printing ink, comprising a modified polyurethane resin soluble in an organic solvent, which is obtained by polymerizing a saturated monomer (B). 2. The ethylenically unsaturated monomer (B) is (meth).
2. An acrylate monomer as a main component.
Binder for printing ink described.