JP2012046587A - Solvent-based gravure ink - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide solvent-based gravure ink that achieves, for various plastic films, excellent coating film properties, such as adhesiveness, blocking resistance, laminate strength, and suitability for boiling resistance, and excellent resistance to fogging of a plate.SOLUTION: In this solvent-based gravure ink formed by mixing a polyurethane resin B and an organic solvent with a pigment dispersion comprising a polyurethane resin A, titanium oxide and the organic solvent, the polyurethane resin A has an alkoxysilyl group represented by general formula (1) at the molecular terminal, and the polyurethane resin B has an amino group at the molecular terminal, and has a hydroxy group in a side chain.

Description

The present invention relates to a solvent-type gravure ink, more specifically, a solvent-type gravure ink excellent in adhesive properties, blocking resistance, laminate strength, boil resistance and other coating film properties and plate-resisting resistance to various plastic films. About.

Gravure ink is widely used for the purpose of imparting cosmetic properties and functionality to a substrate. When a gravure-printed substrate is used as a packaging material, particularly a food packaging material, it is generally subjected to a laminating process. In this case, various printed materials and laminating processes are used depending on the type of contents and the purpose of use.

Printing inks used for such laminate packaging materials have excellent coating properties such as adhesion to various plastic films, blocking resistance, laminate strength, suitability for boil and retort, and by adding polyisocyanate compounds, Gravure inks using a primary amine or a polyurethane resin having a hydroxyl group, which can further improve the physical properties of the coating film, are widely used. However, such polyurethane resins have insufficient pigment dispersibility, and especially when titanium oxide is used as the colorant, the pigment aggregates promote the wear of cylinders and doctors, and printing processes such as plate fog and doctor streaks. Sometimes caused problems.

A silane coupling agent may be used as a surface modifying material for titanium oxide. Examples of general treatment methods include a method in which a silane coupling agent is directly treated on titanium oxide by a dry or wet method, but these methods provide a steric hindrance effect due to an adsorbent on the pigment surface. It was difficult to obtain sufficient pigment dispersibility. Japanese Patent Application Laid-Open No. 6-49404 has developed a printing ink using a urethane resin in which an alkoxysilyl group is incorporated in the molecule. However, the plate resistance, adhesion to a polyolefin film, suitability for boil retort, etc. The coating film physical properties were not compatible.

JP-A-6-49404

An object of the present invention is to provide a solvent-type gravure ink excellent in coating properties such as adhesion, blocking resistance, laminate strength, boil resistance, and anti-fogging property to various plastic films. .

As a result of intensive research in order to solve the above-mentioned problems, the inventors of the present invention have developed a molecular dispersion into a pigment dispersion obtained by mixing and dispersing titanium oxide and a polyurethane resin having an alkoxysilyl group at the end of the molecule. Solvent-type gravure ink obtained by diluting with a polyurethane resin having an amino group at the end and a hydroxyl group in the side chain has excellent adhesion, blocking resistance, laminate strength for a wide variety of plastic films, It has been found that the coating film properties such as boil resistance and the plate fog resistance are excellent.

That is, the present invention relates to a polyurethane dispersion having an amino group and a hydroxyl group in a pigment dispersion comprising an alkoxysilyl group-containing polyurethane resin A obtained by reacting a polymer polyol, a polyisocyanate compound and a chain extender, titanium oxide and an organic solvent. In the solvent-type gravure ink formed by mixing the resin B and the organic solvent,
Polyurethane resin A is
An alkoxysilyl group represented by the following general formula (1) at the end of the molecule

General formula (1)
(In the formula, R ₁ and R ₂ each independently represent a methyl group or an ethyl group, and n represents 2 or 3.)

And polyurethane resin B is
The present invention relates to a solvent-type gravure ink having an amino group at the end of the molecule and a hydroxyl group in a side chain of the molecule.

Furthermore, in the present invention, the polyurethane resin A is
Alkoxysilyl group
1.0 × 10 ^{−5 to} 1.0 × 10 ⁻⁴ mol per 1 g of the resin solid content
It is related with said solvent-type gravure ink characterized by containing.

In the present invention, the polyurethane resin B is
Amine number 1.2-15.0mgKOH / g
And a hydroxyl value of 0.5 to 3.0 mgKOH / g
It is related with said solvent-type gravure ink characterized by being.

Furthermore, the present invention relates to the above-described solvent-type gravure ink, wherein the solid content weight ratio between the polyurethane resin A and the polyurethane resin B is 1: 2 to 1: 8.

The present invention also relates to the above-mentioned solvent-type gravure ink, wherein the total weight of the solid content of the polyurethane resin A and the polyurethane resin B is 15 to 40% by weight with respect to the weight of titanium oxide. It is.

Furthermore, this invention relates to the printed matter formed by printing said solvent-type gravure ink on a base material.

The present invention is a solvent-type gravure ink excellent in coating properties such as adhesiveness, blocking resistance, laminate strength, and boil resistance, and plate fog resistance, which are excellent for various plastic films.

The present invention will be described in detail. In the present invention, “ink” simply means “solvent gravure ink”.

First, the polyurethane resin A having an alkoxysilyl group used in the ink of the present invention will be described. The polyurethane resin A having an alkoxysilyl group at the end of the molecule means that an alkoxysilyl group is introduced into part or all of the end of the polyurethane resin molecule. That is, the polyurethane resin A has an alkoxysilyl group represented by the following general formula (1) at the end of the molecule.
(In the formula, R ₁ and R ₂ each independently represent a methyl group or an ethyl group, and n represents 2 or 3.)
Have

Furthermore, the content of alkoxysilyl groups in the polyurethane resin A of the present invention (per gram of resin)
Is preferably in the range of 1.0 × 10 ^{−5 to} 1.0 × 10 ⁻⁴ mol. When the content of the alkoxysilyl group is less than 1.0 × 10 ⁻⁵ mol, the molecular weight is increased and the solubility is deteriorated, so that the plate resistance is lowered. The content of alkoxysilyl group is 1.0 × 10
^{When it is} larger than ⁻⁴ mol, the molecular weight decreases and the blocking resistance decreases. When the introduction site of the alkoxysilyl group is a side chain of the molecule, sufficient plate resistance fog cannot be obtained.

In the polyurethane resin A used in the ink of the present invention, the compound used for introducing an alkoxysilyl group to the end of the molecule is a compound having an alkoxysilyl group and one amino group that reacts with an isocyanate group. In addition, a compound having an alkoxysilyl group and one isocyanate group, a compound having an alkoxysilyl group and one epoxy group, and the like can be given. Examples of the compound having an alkoxysilyl group and one amino group that reacts with an isocyanate group include 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, and the like. Examples of the compound having an alkoxysilyl group and one isocyanate group include 3-isocyanatepropyltriethoxysilane and 3-isocyanatepropyltrimethoxysilane. Examples of the compound having an alkoxysilyl group and one epoxy group include 3-glycidoxypropyltrimethoxysilane and 3-glycidoxypropylmethyldimethoxysilane.

As the polymer polyol used in the polyurethane resin A used in the ink of the present invention, various known polyols generally used in the production of polyurethane resins can be used, and one or two or more kinds can be used in combination. Also good. For example, polyether polyols (1) of polymers or copolymers such as methylene oxide, ethylene oxide, and tetrahydrofuran; ethylene glycol, 1,2-propanediol, 1,3-propanediol, and 2-methyl-1
, 3-propanediol, 2-ethyl-2-butyl-1,3-propanediol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, pentanediol, 3-
Methyl-1,5-pentanediol, hexanediol, octanediol, 1,4-butynediol, 1,4-butylenediol, diethylene glycol, triethylene glycol, dipropylene glycol, glycerin, trimethylolpropane, trimethylolethane, 1, Saturated or unsaturated low molecular polyols (2) such as 2,6-hexanetriol, 1,2,4-butanetriol, sorbitol, pentaesitol, etc .; these low molecular polyols (2) and adipic acid Phthalic acid, isophthalic acid, terephthalic acid, maleic acid, fumaric acid, succinic acid, oxalic acid, malonic acid, glutaric acid, pimelic acid, speric acid, azelaic acid, sebacic acid, trimellitic acid, pyromellitic acid, etc. Dehydration condensation with carboxylic acids or their anhydrides Polyester polyols (3) obtained by polymerization;
Polyester polyols (4) obtained by ring-opening polymerization of cyclic ester compounds, for example, lactones such as polycaprolactone, polyvalerolactone, poly (β-methyl-γ-valerolactone); the low molecular polyols (2 For example, polycarbonate polyols (5) obtained by reaction with dimethyl carbonate, diphenyl carbonate, ethylene carbonate, phosgene, etc .; polybutadiene glycols (6); obtained by adding ethylene oxide or propylene oxide to bisphenol A Glycols (7); one or more hydroxyethyl, hydroxypropyl acrylate, hydroxyhydroxybutyl, etc., or their corresponding methacrylic acid derivatives, etc. in one molecule, for example, acrylic acid, methacrylic acid or esters thereof Acrylic polyol (8) obtained by copolymerization
) And the like.

Among the polyester polyols (3), a polymer diol obtained from a diol (glycol) and a dibasic acid is a low molecular weight compound having up to 5 mol% of the diols having three or more hydroxyl groups. The polyols (2) can be substituted.

Examples of the polyisocyanate compound used in the polyurethane resin A used in the ink of the present invention include various known aromatic diisocyanates, aliphatic diisocyanates, and alicyclic diisocyanates generally used in the production of polyurethane resins. 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, lysine diisocyanate, cyclohexane-1,4-
Diisocyanate, xylylene diisocyanate, isophorone diisocyanate, dimaryl diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,3-bis (isocyanatemethyl) cyclohexane, methylcyclohexane diisocyanate, norbornane diisocyanate, m-tetramethylxylylene diisocyanate, 4 1,4-diphenylmethane diisocyanate, tolylene diisocyanate, bis-chloromethyl-diphenylmethane diisocyanate, 2,6-diisocyanate-benzyl chloride, dimerized isocyanate in which the carboxyl group of dimer acid is converted to an isocyanate group, and the like. These diisocyanate compounds can be used alone or in admixture of two or more.

The chain extender used in the polyurethane resin A used in the ink of the present invention includes ethylenediamine, propylenediamine, hexamethylenediamine, diethylenetriamine,
In addition to triethylenetetramine, isophoronediamine, dicyclohexylmethane-4,4'-diamine, 2-hydroxyethylethylenediamine, 2-hydroxyethylpropyldiamine, 2-hydroxyethylpropylenediamine, di-2-hydroxyethylethylenediamine, di- It is also possible to use amines having a hydroxyl group in the molecule such as 2-hydroxyethylenediamine, di-2-hydroxyethylpropylenediamine, 2-hydroxypropylethylenediamine, di-2-hydroxypropylethylenediamine, and di-2-hydroxypropylethylenediamine. I can do it. These chain extenders can be used alone or in admixture of two or more.

Moreover, a monovalent active hydrogen compound can also be used as a terminal blocking agent for the purpose of stopping the reaction. Examples of such compounds include dialkylamines such as di-n-butylamine and alcohols such as ethanol and isopropyl alcohol. These end blockers can be used alone or in admixture of two or more.

The polyurethane resin A used in the ink of the present invention is prepared by a conventionally known method, for example, JP-A-62-153366, JP-A-62-153367, JP-A-1-236289.
JP-A-2-64173, JP-A-2-64174, JP-A-2-641.
It can be obtained by a method disclosed in Japanese Patent No. 75. Specifically, a polymer polyol and a diisocyanate compound are reacted in an excess ratio of isocyanate groups to obtain a prepolymer of a terminal isocyanate group, and the resulting prepolymer is placed in a suitable solvent, that is, a non-toluene gravure. Ester solvents such as ethyl acetate, propyl acetate, and butyl acetate that are commonly used as solvents for ink; ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; alcohols such as methanol, ethanol, isopropyl alcohol, and n-butanol Solvents; Hydrocarbon solvents such as methylcyclohexane and ethylcyclohexane; or mixed solvents, and chain extenders and / or
A two-stage method of reacting with a terminal blocking agent, or a polymer polyol, a diisocyanate compound,
It is prepared by a one-step process in which chain extenders and / or end-capping agents are reacted at once in a suitable solvent of the above. Among these methods, it is preferable to use a two-stage method in order to obtain a uniform polyurethane resin. Moreover, when producing a polyurethane resin by a two-stage method, it is made to react so that the sum total (equivalent ratio) of the amino group of a chain extender and / or terminal blocker may become a ratio of 1 / 0.8-1.3. It is preferable. When the equivalent ratio of isocyanate group to amino group is smaller than 1 /, the chain extender and / or the end-capping agent remain unreacted, the polyurethane resin turns yellow, or the odor is generated after printing. There is a case.

Next, the polyurethane resin B having an amino group and a hydroxyl group used in the ink of the present invention will be described. The polyurethane resin B having an amino group at the end of the molecule and a hydroxyl group in the side chain has an amino group introduced into part and all of the end of the polyurethane resin molecule, and a hydroxyl group is introduced into the side chain. Means that The amino group may be introduced into the side chain, but since introduction of only the side chain does not provide sufficient adhesion to the printing substrate, it is essential to introduce it into the terminal. The amine value of the polyurethane resin B of the present invention is 1.2 to 15.0 m.
It is preferable that it is gKOH / g. When the amine value is smaller than 1.2 mgKOH / g, the adhesion to the printing substrate is poor, and when it is larger than 15.0 mgKOH / g, the blocking resistance is poor.
The hydroxyl value is preferably 0.5 to 3.0 mgKOH / g. In addition to the effect of improving the physical properties of the coating film by the reaction with the polyisocyanate curing agent, the hydroxyl group can improve the physical properties of the coating film by the reaction with the alkoxysilyl group introduced into the polyurethane resin A. However, when an isocyanate curing agent is not used, when the hydroxyl value exceeds 3.0 mgKOH / g, a decrease in boil resistance is observed. When the hydroxyl value is less than 0.5 mg KOH / g, the reaction with the alkoxysilyl group introduced into the polyurethane resin A is not sufficient, and a decrease in boil resistance is observed.

The polymer polyol, diisocyanate compound and chain extender used in the polyurethane resin B used in the ink of the present invention can be the same as the polyurethane resin A, and the production method is the same as that of the polyurethane resin A. It can be manufactured by the method.

The weight average molecular weights of the polyurethane resin A and the polyurethane resin B thus obtained are preferably in the range of 20,000 to 100,000. When the weight average molecular weight of the polyurethane resin is less than 20,000, the blocking resistance of the ink composition to be obtained, the strength of the printed film, the oil resistance, etc. tend to be low. The viscosity of the resulting ink composition tends to increase and the gloss of the printed film tends to decrease.

Titanium oxide used as a colorant for the ink of the present invention is not particularly limited,
Common alumina-treated or silica-treated titanium oxide can be used. The ratio of polyurethane resin A and polyurethane resin B is preferably 1: 2 to 1: 8. When the amount of polyurethane resin A exceeds this ratio, the adhesiveness and boil suitability decrease, and when the amount of polyurethane resin B increases, the plate-resistant fog resistance decreases. The ratio of the content of titanium oxide and polyurethane resin in the ink of the present invention is such that the total solid content of polyurethane resin A and polyurethane resin B is 15 to 40% by weight based on the weight of titanium oxide. When the total solid content of the polyurethane resin is less than 15% by weight based on the weight of titanium oxide, the adhesiveness and the laminate strength are lowered, and when it is more than 40% by weight, the blocking resistance is lowered. Even when the polyurethane resin A is used for thinning, good coating film properties cannot be obtained, and even when the polyurethane resin B is used for dispersion, good plate resistance cannot be obtained.

In addition to the polyurethane resin A and polyurethane resin B, the ink of the present invention may be a combination resin, organic solvent, extender pigment, leveling agent, antifoaming agent, wax, plasticizer, infrared absorber, ultraviolet absorber as necessary. , Fragrances, flame retardants and the like. If necessary, it can be mixed with organic pigments and color inks such as yellow, red, indigo and black.

Examples of resins used in combination with the ink of the present invention as needed include polyurethane resins other than the present invention, vinyl chloride-vinyl acetate copolymer resins, chlorinated polypropylene resins, ethylene-vinyl acetate copolymer resins, vinyl acetate. Examples thereof include resins, polyamide resins, acrylic resins, polyester resins, alkyd resins, polyvinyl chloride resins, rosin resins, rosin-modified maleic acid resins, ketone resins, cyclized rubbers, chlorinated rubbers, butyral, and petroleum resins.
The combined resins can be used alone or in admixture of two or more.

As the organic solvent used in the ink of the present invention, aromatic solvents, ketone solvents, ester solvents, alcohol solvents, glycol ether solvents and the like can be used. For example, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, N-propyl acetate, isopropyl alcohol, N-propanol, ethanol,
Examples thereof include methylpropylene glycol, and these can be used as a mixture.

As a method for producing the ink of the present invention, a general dispersing machine such as a roller mill, a ball mill, a pebble mill, an attritor, a sand mill, etc. is used for pigment dispersion, and the polyurethane resin A, titanium oxide and organic solvent having an alkoxysilyl group are used. A pigment dispersion composed of polyurethane resin A is produced, and the resulting pigment dispersion containing polyurethane resin A is blended with a binder and an organic solvent composed of polyurethane resin B having an amino group and a hydroxyl group, and other compounds as required. By doing so, an ink can be manufactured.

In the present invention, in order to produce a pigment dispersion, it is important to disperse using polyurethane resin A having an alkoxysilyl group, and further to perform thinning with polyurethane resin B having an amino group and a hydroxyl group. The solvent-type gravure ink produced by the process is excellent in coating film properties such as excellent adhesion, blocking resistance, laminate strength, and boil resistance to various plastic films, and plate fog resistance.

On the contrary, when a polyurethane resin B having an amino group and a hydroxyl group was used to produce a pigment dispersion, and further dispersed with a polyurethane resin A having an alkoxysilyl group, various physical properties were excellent. Solvent type gravure ink cannot be obtained.

The viscosity of the ink produced by the above method is 1 from the viewpoint of preventing precipitation of the pigment and dispersing it appropriately.
It is preferably in the range of 0 mPa · s or more and 1000 mPa · s or less from the viewpoint of workability efficiency during ink production or printing. In addition, the said viscosity is a viscosity measured at 25 degreeC with the Tokimec B-type viscometer.

The viscosity of the ink can be adjusted by appropriately selecting the type and amount of raw materials used, for example, a polyurethane resin, a colorant, an organic solvent, and the like.

EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to this. In the present invention, “parts” represents parts by weight, and “%” represents% by weight.
The amine value of the polyurethane resin is the number of mg of potassium hydroxide equivalent to hydrochloric acid required to neutralize the amino group contained in 1 g of resin solids, and was measured using a potentiometric titrator. The hydroxyl value of the polyurethane resin is the number of mg of potassium hydroxide required to neutralize acetic acid bonded to the hydroxyl group when 1 g of the resin solid content is acetylated, but the polyurethane resin used in the present invention is Since it was difficult to actually measure the hydroxyl value because it was dissolved in the ester / alcohol mixed solution, the theoretical value in the synthetic formulation of the polyurethane resin was used. The weight average molecular weight of the polyurethane resin is determined by gel permeation chromatography (hereinafter referred to as GP).
C) was used to measure the molecular weight distribution, and the molecular weight was determined as polystyrene equivalent molecular weight.

Production Examples 1 to 8 of the polyurethane resin A used in the ink of the present invention and Production Examples 8 to 20 of the polyurethane resin B are shown in Production Examples 8 to 20.

[Production Example 1]
A polyester diol having a number average molecular weight of 2000 (hereinafter referred to as PMPA) obtained from adipic acid and 3-methyl-1,5-pentanediol was added to a four-necked flask equipped with a thermometer and a stirrer.
2000) 183.76 parts, polypropylene glycol (number average molecular weight 2000,
(Hereinafter referred to as PPG2000) 46.00 parts, isophorone diisocyanate 53.13 parts,
90 parts of 0.02-part tin 2-ethylhexanoate and 353.9 parts ethyl acetate under a nitrogen stream
The mixture was reacted at 0 ° C. for 6 hours to obtain 636.85 parts of a solvent solution of a terminal isocyanate prepolymer. Then 15.00 parts of isophorone diamine and 3-aminopropyltrimethoxysilane.
A mixture of 15 parts, 136.00 parts of ethyl acetate and 210.00 parts of isopropyl alcohol was gradually added at room temperature to 636.85 parts of a solvent solution of the obtained terminal isocyanate prepolymer, followed by chain extension. Reaction at 50 ° C. for 1 hour, solid content 30%, amine number 0
. 1 or less, a hydroxyl value of 0.1 or less, and a polyurethane resin solution (A1) was obtained. Moreover, the weight average molecular weight measured by GPC of this polyurethane resin was 38000.

[Production Example 2-8]
The polyurethane resin solution (A2 to A8) was prepared in the same manner as in Production Example 1 with the charging ratio shown in Table 1.
Got.

[Production Example 9]
In a four-necked flask equipped with a thermometer and a stirrer, 220.03 parts of PMPA2000,
56.14 parts of isophorone diisocyanate, 0.03 part of tin 2-ethylhexanoate and 80.00 parts of ethyl acetate were reacted at 90 ° C. for 6 hours under a nitrogen stream, and 356.20 parts of the solvent solution of the terminal isocyanate prepolymer was added. Obtained. Then 22.68 parts isophorone diamine,
To a mixture of 1.12 parts of 2- (2-aminoethylamino) ethanol, 410.00 parts of ethyl acetate and 210 parts of isopropyl alcohol, 356.20 parts of the solvent solution of the obtained terminal isocyanate prepolymer was gradually added at room temperature. To extend the chain and then to 1 at 50 ° C.
By reacting for a period of time, a polyurethane resin solution (B1) having a solid content of 30%, an amine value of 4.0, and a hydroxyl value of 2.0 was obtained. Moreover, the weight average molecular weight measured by GPC of this polyurethane resin was 51.
000.

[Production Example 10-17]
A polyurethane resin solution (B2 to B9) was obtained in the same manner as in Production Example 9 at the charging ratio shown in Table 2.

[Production Example 18]
In a four-necked flask equipped with a thermometer and a stirrer, 223.26 parts of PMPA2000,
56.97 parts of isophorone diisocyanate, 0.03 part of tin 2-ethylhexanoate and 80.00 parts of ethyl acetate were reacted at 90 ° C. for 6 hours under a nitrogen stream, and 360.26 parts of a solvent solution of a terminal isocyanate prepolymer was obtained. Obtained. Then isophoronediamine 19.74 parts,
A mixture of 410.00 parts of ethyl acetate and 210.00 parts of isopropyl alcohol was gradually added to the solvent solution 360.26 parts of the obtained terminal isocyanate prepolymer at room temperature, followed by chain extension. The mixture was reacted for 1 hour to obtain a polyurethane resin solution (B10) having a solid content of 30%, an amine value of 0.1 or less, and a hydroxyl value of 0.1 or less. Moreover, the weight average molecular weight measured by GPC of this polyurethane resin was 53000.

[Production Example 19]
In a four-necked flask equipped with a thermometer and a stirrer, 223.80 parts of PMPA2000,
57.11 parts of isophorone diisocyanate, 0.03 part of tin 2-ethylhexanoate and 80.00 parts of ethyl acetate were reacted at 90 ° C. for 6 hours under a nitrogen stream, and 360.94 parts of a solvent solution of a terminal isocyanate prepolymer was obtained. Obtained. Then 17.93 parts isophorone diamine,
A mixture of 1.13 parts of 2- (2-aminoethylamino) ethanol, 410.00 parts of ethyl acetate and 210.00 parts of isopropyl alcohol was added to 360.94 parts of the solvent solution of the obtained terminal isocyanate prepolymer at room temperature. Slowly add to extend the chain, then 50
The mixture was reacted at ° C for 1 hour to obtain a polyurethane resin solution (B11) having a solid content of 30%, an amine value of 0.1 or less, and a hydroxyl value of 2.0 or less. Moreover, the weight average molecular weight measured by GPC of this polyurethane resin was 52,000.

[Production Example 20]
In a four-necked flask equipped with a thermometer and a stirrer, 219.51 parts of PMPA2000,
56.01 parts of isophorone diisocyanate, 0.03 part of tin 2-ethylhexanoate and 80.00 parts of ethyl acetate were reacted at 90 ° C. for 6 hours under a nitrogen stream, and 355.55 parts of a solvent solution of a terminal isocyanate prepolymer was added. Obtained. Then 24.45 parts of isophorone diamine,
To a mixture of 410.00 parts of ethyl acetate and 210.00 parts of isopropyl alcohol, 355.55 parts of the solvent solution of the obtained terminal isocyanate prepolymer was gradually added at room temperature to perform chain extension, and then at 50 ° C. The mixture was reacted for 1 hour to obtain a polyurethane resin solution (B12) having a solid content of 30%, an amine value of 4.0, and a hydroxyl value of 0.1 or less. Moreover, the weight average molecular weight measured by GPC of this polyurethane resin was 50000.

[Example 1]
35.0 parts of titanium oxide (Taita Titanic JR805), polyurethane resin solution (
A1) After 8.0 parts of ethyl acetate, 8.0 parts of ethyl acetate and 3.0 parts of isopropyl alcohol were mixed with a dissolver, dispersion was performed with a sand mill to obtain 54.0 parts of a pigment dispersion. To this pigment dispersion, 30.0 parts of polyurethane resin solution (B1), 10.0 parts of ethyl acetate and 6.0 parts of isopropyl alcohol were added and mixed with a dissolver to produce the solvent-type gravure ink of the present invention.

[Examples 2 to 22]
The solvent-type gravure ink of the present invention was produced in the same manner as in Example 1 with the preparations shown in Tables 3 and 4.

[Comparative Examples 1-8]
A solvent-type gravure ink was produced in the same manner as in Example 1 with the preparation shown in Table 5.

50 parts of a mixed solvent of methyl ethyl ketone, N-propyl acetate and isopropyl alcohol (weight ratio 40:40:20) was added to and mixed with 100 parts of the obtained solvent-type gravure ink to obtain a one-component diluted ink. .

To 100 parts of the obtained solvent-type gravure ink, 50 parts of a mixed solvent of methyl ethyl ketone, N-propyl acetate and isopropyl alcohol (weight ratio 40:40:20) and 1.5 parts of hexamethylene diisocyanate curing agent were added. Mixing was performed to obtain a two-component diluted ink.

1) Plate-resistant fog resistance The diluted ink of the 1-component and 2-component specifications after the above adjustment is placed on a gravure printing machine, and the plate-resistance is visually observed from the state of the plate after idling for 60 minutes at a printing speed of 200 m / min. Judged. The determination criteria were as follows. The evaluation results are shown in Table 6.
◎ ... No plate cover is seen at all.
O: Plate fog is seen at the edge of the image.
Δ: Plate fog is seen at the edge of the image and inside the image.
X: Plate cover is seen on the entire plate including the non-image area.
A and O are ranges where there is no practical problem.

For the coating film physical property evaluation, the diluted ink of the one-component specification after the above adjustment was subjected to a corona-treated OPP film (Pyrene P2161 # 20 manufactured by Toyobo Co., Ltd.), corona using a gravure proofing machine equipped with a plate depth of 35 μm Treated PET film (E5100 # 12 manufactured by Toyobo Co., Ltd.)
And it printed on the corona treatment nylon film (Emblem ON-RT # 15 by Unitika Co., Ltd.), and dried at 40-50 degreeC, and the printed matter was obtained. The following tests were performed using the obtained printed matter.

2) Adhesiveness After leaving the said printed matter for 24 hours, the cellophane tape was affixed on the printing surface, and the appearance state of the printed film when this was peeled off rapidly was determined visually. The determination criteria were as follows. The evaluation results are shown in Table 6.
[Criteria for Adhesion to OPP Film]
A: 80% or more of the printed film remained on the film.
O: 50 to 80% of the printed film remained on the film.
Δ: 30 to 50% of the printed film remained on the film.
X: 30% or less of the printed film remained in the film.
A and O are ranges where there is no practical problem.
[Criteria for Adhesion to PET Film and Nylon Film]
◎ ・ ・ ・ No peeling at all.
O: More than 80% of the printed film remained on the film.
Δ: 50 to 80% of the printed film remained on the film.
X: 50% or less of the printed film remained in the film.
A and O are ranges where there is no practical problem.

3) Blocking resistance 10 kgf / cm by stacking films so that the printed surface and the non-printed surface of the printed matter are in contact with each other.
A weight of ² was applied, and the sample was allowed to stand in an environment of 40 ° C. and 80% RH for 24 hours. The evaluation results are shown in Table 6.
◎ ・ ・ ・ 0% transfer of ink to non-printing surface
○: Transfer amount less than 10% Δ: Transfer amount of 10% or more and less than 30% ×… Transition amount of 30% or more

4) Extrusion laminate strength and boil resistance After applying the isocyanate-based anchor coating agent to the printed matter of the above PET film and nylon film, laminating molten polyethylene with an extrusion laminator, and aging at 40 ° C for 48 hours The laminate strength was measured. Moreover, the presence or absence of the lame float after the boil processing for 30 minutes at 85 degreeC was visually determined by the external appearance. The determination criteria were as follows. The evaluation results are shown in Table 6.
◎ ・ ・ ・ There is no Lami floating.
〇 ・ ・ ・ Blisters were slightly generated.
Δ: Some delamination occurred.
X: Delamination occurred on the entire surface.
A and O are ranges where there is no practical problem.

From the evaluation results, the pigment dispersion obtained by mixing and dispersing titanium oxide and a polyurethane resin having an alkoxysilyl group at the end of the molecule has a polyurethane resin having an amino group at the end of the molecule and a hydroxyl group in the side chain. The solvent-type gravure ink obtained by diluting with, has excellent adhesion, blocking resistance, laminate strength,
It was found that the ink was excellent in coating film properties such as boil resistance and plate fog resistance.

Claims (6)

In a solvent-type gravure ink obtained by mixing a polyurethane resin A having an alkoxysilyl group, a titanium oxide and a pigment dispersion composed of an organic solvent, a polyurethane resin B having an amino group and a hydroxyl group, and an organic solvent,
Polyurethane resin A is
An alkoxysilyl group represented by the following general formula (1) at the end of the molecule

General formula (1)

(In the formula, R ₁ and R ₂ each independently represent a methyl group or an ethyl group, and n represents 2 or 3.)

And polyurethane resin B is
A solvent-type gravure ink having an amino group at a terminal of the molecule and a hydroxyl group in a side chain of the molecule. The polyurethane resin A is
Alkoxysilyl group
1.0 × 10 ^{−5 to} 1.0 × 10 ⁻⁴ mol per 1 g of the resin solid content
The solvent-type gravure ink according to claim 1, which is contained. The polyurethane resin B is
Amine number 1.2-15.0mgKOH / g
And a hydroxyl value of 0.5 to 3.0 mgKOH / g
The solvent-type gravure ink according to claim 1 or 2, wherein The solid content weight ratio between the polyurethane resin A and the polyurethane resin B is 1: 2-1.
The solvent-type gravure ink according to any one of claims 1 to 3, wherein 5. The solvent-type gravure ink according to claim 1, wherein the total weight of the solid content of the polyurethane resin A and the polyurethane resin B is 15 to 40% by weight with respect to the weight of titanium oxide.   A printed matter obtained by printing the solvent-type gravure ink according to claim 1 on a substrate.