JPH0616988A - Printing ink composition - Google Patents

Abstract

PURPOSE:To provide a printing ink composition containing a polycarbodiimide compound, exhibiting excellent adhesiveness to various non-absorbing substrates such as plastic films, and giving printed products excellent in blocking resistance and ethyl acetate resistance. CONSTITUTION:The composition contains a polycarbodiimide compound preferably as a part of a printing ink binder. The polycarbodiimide compound is preferably produced by condensing an organic isocyanate compound at 100-160 deg.C in the presence of a catalyst with blowing nitrogen gas in a solvent. The catalyst is preferably 1-ethyl-3-methyl-3-phosphopropylene oxide, etc. The organic isocyanate compound is preferably an aliphatic isocyanate such as n-butyl isocyanate and/or an alicyclic isocyanate such as isophorone diisocyanate.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a printing ink composition, particularly a printing ink composition suitable for plastic films.

[0002]

2. Description of the Related Art Conventionally, a printing ink for a plastic film, which uses a urethane resin solution as a binder, has been used (for example, JP-A-52-41694 and JP-A-SHO).
61-225211 and JP-A-55-25453).

[0003]

However, these are not only inadequate in the adhesiveness and blocking resistance of the printed matter, but in the case of laminating, inks are admixed with ethyl acetate which is the solvent of the adhesive. There is a problem that the film is easily damaged. Further, higher resistance to hot water sterilization of laminated films has been required.

[0004]

In view of such circumstances, the present inventors have shown excellent adhesiveness to non-absorbent substrates such as various plastic films, and have blocking resistance and ethyl acetate resistance of printed matter. The present invention has been achieved as a result of intensive studies aimed at obtaining a printing ink having excellent heat resistance and water resistance of a laminated film.

That is, the present invention relates to a printing ink composition containing a polycarbodiimide compound.

The polycarbodiimide compound used in the present invention has a plurality of carbodiimide bonds (-N =
It has C = N-) and can be obtained by a condensation reaction of an organic isocyanate compound in the presence of a catalyst.

N OCN-R-OCN → (-RN-C = N-) _n + (n-1) CO ₂

Examples of the organic isocyanate compound include aliphatic, alicyclic, araliphatic and aromatic mono-, di- and triisocyanates. Examples of these isocyanates include aliphatic isocyanates such as aliphatic monoisocyanates [n-propyl isocyanate, isopropyl isocyanate, n-butyl isocyanate, stearyl isocyanate, etc.]; aliphatic diisocyanates [1,6-hexamethylene diisocyanate (abbreviated as HDI), 2 Of low molecular weight glycols such as 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, ethylene glycol and propylene glycol, and polymer glycols such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol and polyester diol, and the above aliphatic diisocyanate Prepolymer, etc.]; Aliphatic triisocyanate [lysine triisocyanate, said aliphatic diisocyanate] Cyanate trimers (HDI trimers, etc.), low molecular weight triols such as trimethylolpropane and adducts of said aliphatic diisocyanates, etc.]; alicyclic isocyanates such as alicyclic diisocyanates [isophorone diisocyanate (abbreviated as IPDI), Hydrogenated 4,4'-diphenylmethane diisocyanate, methylcyclohexylene diisocyanate, isopropylidene dicyclohexyl 4,4'-diisocyanate, prepolymers of low-molecular and high-molecular glycols with the alicyclic diisocyanate, etc.]; alicyclic Triisocyanate [trimer of said alicyclic diisocyanate, adduct of low molecular weight triol and said alicyclic diisocyanate]; araliphatic isocyanate such as araliphatic diisocyanate [xylylene diisocyanate] Ate, prepolymers of low molecular weight and high molecular weight glycols with the araliphatic diisocyanate]; araliphatic triisocyanates [trimers of the araliphatic diisocyanates, adducts of low molecular weight triols with the araliphatic diisocyanates, etc. ]; Aromatic isocyanate such as aromatic monoisocyanate [phenylisocyanate]; aromatic diisocyanate [4,4′-diphenylmethane diisocyanate,
Tolylene diisocyanate, prepolymers of low molecular weight and high molecular weight glycols with the aromatic diisocyanate, etc.]; Aromatic triisocyanates [Trimers of the aromatic diisocyanate, low molecular weight triols and adducts of the aromatic diisocyanates], and Mixtures of two or more of these may be mentioned.

Examples of the catalyst used in the carbodiimide formation reaction include phospholenes and phospholene oxides. Of these, particularly preferred catalysts are 1-
Examples thereof include ethyl-3-methyl-3-phospholene oxide, 1-phenyl-3-methyl-3-phospholene oxide and 1-phenyl-3-methyl-2-phospholene oxide.

The reaction is usually carried out in a solvent while blowing nitrogen gas with sufficient stirring. The preferred reaction temperature is
It is in the range of 100 to 160 ° C. If the temperature is lower than this range, the reaction time tends to be too long, and if it is higher than this range, side reactions tend to occur, which is not preferable.

The solvent used must have a boiling point at which a temperature sufficient for the reaction to proceed can be obtained, and must not have an active hydrogen group that is reactive with the starting isocyanate and the carbodiimide formed. Can be given. Examples of such a solvent include aromatic hydrocarbons such as toluene, xylene and diethylbenzene; aliphatic esters such as butyl acetate, amyl acetate, propyl propionate and ethyl butyrate; diethylene glycol diacetate, dipropylene glycol dibutyrate, Hexylene glycol diacetate, glycol diacetate, methyl glycol acetate, ethyl glycol acetate, butyl glycol acetate, ethyl diglycol acetate, butyl diglycol acetate, and other glycol ether esters; ethyl butyl ketone, acetophenone, propiophenone, diisobutyl ketone , Cyclohexanone and other ketones; decalin and other alicyclic hydrocarbons.

One of the preferred embodiments of the present invention is to add the polycarbodiimide compound (A) as an additive as a part of the printing ink binder. As a result, the ink film exhibits excellent adhesiveness to various plastic films, and improves the blocking resistance and ethyl acetate resistance of the printed matter.

Suitable polycarbodiimides (A) in this case are preferably those from the abovementioned aliphatic and / or cycloaliphatic mono- and diisocyanates, the molar ratio of monoisocyanate: diisocyanate being from 2: 1 to 2:
Those obtained by reacting in the range of 10, preferably 2: 2 to 2: 4 are mentioned. As a typical example, when 2 mol of n-butyl isocyanate is reacted with 3 mol of IPDI, a polycarbodiimide oligomer having an average of 4 carbodiimide bonds is obtained.

Such polycarbodiimide is added in a proportion of 0.2 to 10% based on the total solid content of the printing ink binder. If the amount added is less than this range, the desired effect will not be obtained. On the other hand, if the amount is more than this range, the stability of the ink tends to deteriorate, which is not preferable. As the main component of the binder, the polyurethane resin (B) described below is preferable.

A more preferred embodiment of the present invention uses the polycarbodiimide compound (A) as the main component of the binder of the printing ink. As a result, the ink film exhibits excellent adhesion to various plastic films, improves the blocking resistance and ethyl acetate resistance of the printed matter, and at the same time improves the hot water resistance of the laminate.

Suitable polycarbodiimide compounds (A) in this case include those using a urethane prepolymer having a terminal isocyanate group obtained by the reaction of a polymeric diol and an organic diisocyanate as the starting diisocyanate. The reaction may be by itself, but this and other diisocyanates and / or
Alternatively, monoisocyanates, or other diisocyanates and / or monoalcohols may be used. Here, since monoisocyanate and monoalcohol act as a polymerization terminator, they are useful for controlling the molecular weight.

Examples of the above-mentioned polymer diol include polyester diols such as dicarboxylic acids (adipic acid, azelaic acid, sebacic acid, succinic acid, glutaric acid, maleic acid, fumaric acid, phthalic acid, etc.) and glycols (ethylene glycol, propylene glycol). , 1,4-butanediol, 1,3-butanediol, 1,6-hexanediol, 1,8-octamethylenediol, neopentyl glycol, bishydroxymethylcyclohexane, bishydroxyethylbenzene, alkyl dialkanolamine, etc.) Obtained by polycondensation of polyethylene adipate, polybutylene adipate, polyhexamethylene adipate, polyethylene / propylene adipate; polylactone diol obtained by ring-opening polymerization of lactone. If polycaprolactone diol,
Polyvalerolactone diols and the like, and polyether polyols such as polyether polyols [alkylene oxides of low molecular weight glycols (ethylene glycol, propylene glycol, 1,4-butanediol, etc.) (alkylene oxides having 2 to 4 carbon atoms such as ethylene oxide, propylene oxide and butylene). Oxide) adduct and ring-opening polymerization product of the above alkylene oxide] Specific examples include polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, and mixtures of two or more thereof.

Of these, polyester diols are particularly preferable. The average molecular weight of the polymeric diol (as measured by hydroxyl value) is usually 500 to 40,000, preferably 800 to 8
It is 000.

The diisocyanates and monoisocyanates used in the synthesis of the polycarbodiimide (A) used as the main component of the binder are the aliphatic, alicyclic, araliphatic and aromatic diisocyanates mentioned in the description of the above-mentioned organic isocyanate compound. And the same as monoisocyanate.

The monoalcohol used as a polymerization terminator in the synthesis of the polycarbodiimide (A) used as the main component of the binder is methyl alcohol, ethyl alcohol, n-propyl alcohol, iso-propyl alcohol, n-butyl alcohol, iso- Butyl alcohol and the like.

In the present invention, the polycarbodiimide (A) used as the main component of the binder can be manufactured by the following method. For example, an organic diisocyanate and a polymeric diol are reacted at a molar ratio in excess of an isocyanate group to form a prepolymer having a terminal isocyanate group, the prepolymer is diluted with a solvent to form a solvent solution of the prepolymer, and the above catalyst is added to the solution. The reaction can be performed by heating and stirring. It is also possible to add another diisocyanate to the above prepolymer and then react. When a polymerization terminator is used if necessary, the method of adding the polymerization terminator is preferably such that when a monoisocyanate is used as the polymerization terminator, it is added simultaneously with the above prepolymer and other diisocyanates. When alcohol is used, a method of adding an excess amount at the stage when the polymerization reaction has sufficiently proceeded is preferable.

The molecular weight of the polycarbodiimide compound (A) thus obtained is usually 5,000 to 100,000, preferably 8,000 to 80,000.

Such a polycarbodiimide may be used alone as a printing ink binder, but may be used in combination with other resins, and preferably the polyurethane resin (B) described later is used in combination.

Polycarbodiimide compound used as the main component of the polymer diol in the polyurethane resin (B) from the polymer diol, the organic diisocyanate and the chain extender used as a part of the binder of the printing ink of the present invention. Examples thereof include the same as the polymer diol described in the section (A), and the preferable ones are also the same.

Examples of the organic diisocyanate include aliphatic diisocyanates [1,6-hexamethylene diisocyanate (abbreviated as HDI), 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, low-molecular glycols such as ethylene glycol and propylene glycol]. Prepolymer with the above aliphatic diisocyanate, etc .; alicyclic diisocyanate [isophorone diisocyanate (abbreviated as IPDI), hydrogenated 4,4'-
Diphenylmethane diisocyanate, methylcyclohexylene diisocyanate, isopropylidene dicyclohexyl 4,4′-diisocyanate, prepolymers of low molecular weight glycols and the alicyclic diisocyanates, etc .; araliphatic diisocyanates [xylylene diisocyanates, low molecular weight glycols] Prepolymers with the above-mentioned aromatic-aliphatic diisocyanates]; Aromatic diisocyanates [Prepolymers with 4,4'-diphenylmethane diisocyanate, tolylene diisocyanate, low-molecular glycols and the above-mentioned aromatic diisocyanates];
And mixtures of two or more of these. Of these, preferred are aliphatic diisocyanates and alicyclic diisocyanates and mixtures thereof.

Examples of the chain extender include low molecular weight glycols (ethylene glycol, propylene glycol, 1,
4-butanediol, 1,6-hexanediol, etc.), aliphatic diamine (ethylenediamine, hexamethylenediamine, 2,2,4-trimethylhexamethylenediamine, etc.), alicyclic diamine [isophoronediamine (abbreviated as IPDA), Dicyclohexylmethane-4
4'-diamine, isopropylidenedicyclohexyl-
4,4′-diamine, 1,4-diaminocyclohexane, etc.) and mixtures of two or more thereof.
Of these, preferred are low molecular weight glycols, alicyclic diamines and mixtures of two or more thereof.

If desired, a polymerization terminator may be used. Examples of the polymerization terminator used include monohydric alcohols such as methyl alcohol, ethyl alcohol, n-propyl alcohol, iso-propyl alcohol, n-butyl alcohol and iso-butyl alcohol; monoethylamine, n-propylamine, diethylamine, di-n. Examples include monoamines such as -propylamine and di-n-butylamine; hydroxyl monoamines such as monoethanolamine and diethanolamine.

The molar ratio of the polymeric diol and the chain extender is usually
It is 1: 0.3 to 1: 8, preferably 1: 0.5 to 1: 6. N
The ratio of CO and the active hydrogen-containing group (OH, NH _2, NH, etc.) is usually 0.8: 1 to 1.2: 1.

In the present invention, the polyurethane resin (B)
Can be manufactured by the following method. For example, an organic diisocyanate and a polymeric diol are reacted at a molar ratio in excess of an isocyanate group to form a prepolymer having a terminal isocyanate group, the prepolymer is diluted with a solvent to prepare a solvent solution of the prepolymer, and then extended with a chain extender. Prepolymer method, organic diisocyanate, polymeric diol,
It can be performed by a one-shot method in which a chain extender is reacted in a solvent solution in a single step. It is also possible to add a part of the chain extender (for example, low molecular weight glycol) during the production of the above-mentioned prepolymer and to extend it with the rest of the chain extender (for example, diamine). When a polymerization terminator is used if necessary, the method of adding the polymerization terminator may be such that it is added and reacted before the chain extension reaction, or is added at the same time as the chain extender, or after the chain extension reaction is completed, the reaction is stopped by adding it. Either method may be used.

When a solvent is used, examples of the solvent used include alcohols such as ethanol, isopropanol and n-butyl alcohol; ketones such as acetone, methyl ethyl ketone and cyclohexanone; ethers such as dioxane and tetrahydrofuran; aromas such as toluene. Group hydrocarbons; amides such as dimethylformamide and dimethylacetamide; halogenated hydrocarbons such as chlorobenzene, trichlene, perclen; esters such as ethyl acetate and butyl acetate, and mixtures of two or more thereof. Solubility and economy From the viewpoint of properties, it is preferably isopropanol, n-butyl alcohol, acetone, methyl ethyl ketone, ethyl acetate, toluene and a mixture of two or more thereof.

A catalyst may be used in the reaction. Examples of such a catalyst include tertiary amine-based catalysts such as triethylamine and dimethylaniline, and metal-based catalysts such as tin and zinc.

The molecular weight of the polyurethane resin (B) thus obtained is usually 5,000 to 100,000, preferably 8,
It is between 000 and 80,000.

The solvent used in the solvent solution is (A)
Those used in the production of (B) and (B) may be used as they are, and those which are additionally used include, for example, alcohols such as ethanol and isopropanol; ketones such as acetone, methyl ethyl ketone and cyclohexanone; dioxane and tetrahydrofuran. Ethers; aromatic hydrocarbons such as toluene; amides such as dimethylformamide and dimethylacetamide; halogenated hydrocarbons such as chlorobenzene, trichlene, perclen; esters such as ethyl acetate and butyl acetate, and mixtures of two or more thereof. To be Preferred are isopropanol, acetone, methyl ethyl ketone, ethyl acetate, toluene and a mixture of two or more thereof.

The solid concentration of the polycarbodiimide (A) and polyurethane resin (B) solutions is usually 5 to 70%, preferably 10 to 60%. Viscosity is usually 50-500,000
It is preferably 100 to 100,000 (cps / 20 ° C).

For producing the printing ink of the present invention, for example, a binder containing the polycarbodiimide (A) and the polyurethane resin (B) according to the present invention is usually made into a solution of 5 to 50% by weight, preferably 10 to 30% by weight. It is carried out by adding a pigment and, if necessary, other resins and additives such as a pigment dispersant and the like to the leverage and kneading them using a usual ink manufacturing apparatus such as a ball mill. Examples of the other resins include polyamide, nitrocellulose, polyacrylic acid ester, polyvinyl chloride, vinyl chloride / vinyl acetate copolymer, styrene-butadiene rubber, and epoxy resin.

As a target to which the printing ink of the present invention is applied, a polyester film, a nylon film, a polypropylene film or the like is suitable.

The printing ink of the present invention may be a one-pack type printing ink, but it may also be a two-pack type printing ink in combination with a polyisocyanate curing agent. In this case, the polyisocyanate-based curing agent is, for example, an adduct body synthesized from 1 mol of trimethylolpropane and 3 mol of tolylene diisocyanate, HDI or IPDI; HDI.
Alternatively, an isocyanurate group-containing trimer synthesized by cyclic trimerization of an isocyanate group of IPDI; a partial buret reaction product synthesized from 1 mol of water and 3 mol of HDI, and a mixture of two or more thereof are preferable. In the case of a two-component printing ink, the addition amount of the polyisocyanate curing agent is usually 0.5 to 10% by weight based on the ink.

The printing method using the printing ink of the present invention may be the same as that of the conventional gravure ink.

[0039]

EXAMPLES Next, the present invention will be described with reference to Examples and Comparative Examples.
This will be described more specifically, but the present invention is not limited thereto.

Examples 1 and 2, Comparative Example 1 Polycarbodiimide A-1 A 1 liter round bottom flask equipped with a stirrer, thermometer, condenser and nitrogen gas inlet tube was charged with 68.8 g of butyl isocyanate, 231.2 g of IPDI and amyl acetate. 270 g and 10% of 1-phenyl-3-methyl-2-phosphorene oxide
Charge 30 g of xylene solution and blow with nitrogen gas.
The mixture was heated to 0 ° C., stirred for 26 hours, cooled, and taken out. Yield 533.4g, non-volatile content 44.0%. From the infrared absorption spectrum, the absorption peak based on isocyanate (22
60 cm ^-1 ) disappeared, and the generation of an absorption peak (2130 cm ^-1 ) based on carbodiimide was confirmed.

Polyurethane resin B-1 A 2 liter round bottom flask equipped with a stirrer, thermometer, condenser and nitrogen gas inlet tube had an average molecular weight of 200.
Charge 319g of polycaprolactone diol 0
The temperature was raised to 70 ° C with stirring.

At the same temperature, 71 g of isophorone diisocyanate was added and the reaction was carried out for 7 hours while flowing nitrogen gas, and then methyl ethyl ketone and ethyl acetate were added.
While adding g each, the mixture was cooled to 40 ° C and uniformly dissolved.

24 g of isophoronediamine and 290 g of isopropyl alcohol were added to the prepolymer thus obtained.
Is added, and the mixture is reacted at the same temperature of 40 ° C for 5 hours.
A colorless transparent polyurethane resin solution having a Gardner viscosity of YZ of 30% at 25 ° C. was obtained.

Then, 50 parts of the polyurethane resin B-1 thus obtained was diluted with 10 parts of methyl ethyl ketone, 10 parts of ethyl acetate and 5 parts of isopropyl alcohol, 25 parts of titanium oxide was added, and the mixture was kneaded with a ball mill for 24 hours. did. Polycarbodiimide A-1 was added to the mixture to give the composition shown in Table 1 to obtain the printing ink of the present invention.

[0045]

[Table 1]

Examples 3 to 4, Comparative Example 2 Polycarbodiimide A-2 In a 1 liter round bottom flask equipped with a stirrer, thermometer, condenser and nitrogen gas inlet tube, butyl isocyanate 111.2 g, HDI 188.8 g, amyl acetate. 270 g and 10% of 1-phenyl-3-methyl-2-phosphorene oxide
Charge 30 g of xylene solution and blow with nitrogen gas.
The mixture was heated to 0 ° C., stirred for 24 hours, cooled, and taken out. Yield 520.4g, nonvolatile content 43.0%. From the infrared absorption spectrum, the absorption peak based on isocyanate (22
60 cm ^-1 ) disappeared, and the generation of an absorption peak (2130 cm ^-1 ) based on carbodiimide was confirmed.

Polyurethane resin B-2 A 2-liter round bottom flask equipped with a stirrer, thermometer, condenser and nitrogen gas inlet tube had an average molecular weight of 180.
0 g of polytetramethylene ether glycol (288 g) was charged and the temperature was raised to 70 ° C. with stirring.

At the same temperature, 71 g of isophorone diisocyanate was added and the reaction was carried out for 7 hours while flowing nitrogen gas, and then methyl ethyl ketone and ethyl acetate were added.
While adding g each, the mixture was cooled to 50 ° C. and dissolved uniformly.

To the prepolymer thus obtained, 24 g of isophoronediamine was added and reacted at the same temperature of 50 ° C. for 2.5 hours to extend the chain. Then, 2 g of diethylamine and 270 g of isopropyl alcohol were added and reacted at the same temperature for another 2.5 hours. Thus, a colorless transparent polyurethane resin solution having a nonvolatile content of 30% and a Gardner viscosity at 25 ° C. of VW was obtained.

Then, 50 parts of the polyurethane resin B-2 thus obtained was diluted with 10 parts of methyl ethyl ketone, 10 parts of ethyl acetate and 5 parts of isopropyl alcohol, 25 parts of titanium oxide was added, and the mixture was ground in a ball mill for 24 hours. did. Polycarbodiimide A-2 was added to the mixture to give the composition shown in Table 2 to obtain a printing ink of the present invention.

[0051]

[Table 2]

Examples 5 to 6 Polycarbodiimide A-3 A 1 liter round bottom flask equipped with a stirrer, thermometer, condenser and nitrogen gas inlet tube had an average molecular weight of 200.
100 g of polyester diol obtained by the esterification reaction of 1,4-butanediol and adipic acid and 25 g of 4,4′-diphenylmethane diisocyanate were charged and reacted at 80 ° C. for 1.5 hours. 1-phenyl here
After diluting with 75 g of toluene containing 0.5 g of -3-methyl-3-phospholen-1-oxide, heat it at the reflux temperature and cool it to 50 ℃ when Gardner viscosity at 25 ℃ reaches ZZ _1. 12 g of alcohol was added and the reaction was continued at 50 ° C. at the same temperature for 2 hours. Due to the nonvolatile content of 22.0%, viscosity U, and infrared absorption spectrum, the isocyanate-based absorption peak (2260 cm ^-1 ) disappeared, and the carbodiimide-based absorption peak (2130 c
m ^-1 ) was confirmed.

Next, the composition having the composition shown in Table 3 was kneaded with a ball mill for 24 hours to obtain a printing ink of the present invention.

[0054]

[Table 3]

Examples 7 to 8 Polycarbodiimide A-4 A 1 liter round bottom flask equipped with a stirrer, thermometer, condenser and nitrogen gas inlet tube had an average molecular weight of 200.
Charge 100 g of polycaprolactone diol 0
The temperature was raised to 70 ° C with stirring. At the same temperature, 22 g of isophorone diisocyanate was added, and nitrogen gas was passed through.
React over time. After adding 0.8 g of n-butylisocyanate and 75 g of toluene containing 0.5 g of 1-phenyl-3-methyl-3-phosphorene-1-oxide, and diluting it,
The heating and stirring were continued for 30 hours at the reflux temperature. Nonvolatile content 25.0%, viscosity W. From the infrared absorption spectrum, the absorption peak based on isocyanate (2260 cm ^-1 ) disappeared and the absorption peak based on carbodiimide (2130 c ^-1 ) disappeared.
m ^-1 ) was confirmed.

Next, the composition having the composition shown in Table 4 was kneaded in a ball mill for 24 hours to obtain a printing ink of the present invention.

[0057]

[Table 4]

Using the printing inks of Examples 1 to 8 and Comparative Examples 1 and 2, a small gravure rotary printing machine [TM type manufactured by Toya Iron Works Co., Ltd.] was used with a gravure mesh roll.
Solid printing was performed on a treated polypropylene film (abbreviated as OPP), a polyester film (abbreviated as PET) and a nylon film (abbreviated as NY) to obtain a printed matter.

The printed matter obtained was subjected to the following tests and the results shown in Table 5 were obtained. (1) Adhesiveness Nichiban cellophane tape (18 mm width) was attached to the printed surface, and one state of this cellophane tape was rapidly peeled in a direction perpendicular to the printed surface, and the state of the printed surface was observed.

(2) Blocking resistance The printed surface and the non-printed surface are overlaid, and the temperature is 40 ° C and the humidity is 60%.
In RH, a load of 5.0 kg / cm ² was applied and after 24 hours, it was peeled off and the surface condition was observed.

(3) Ethyl acetate resistance Using the same printing machine as described above, ethyl acetate was printed again on the printing surface with a gravure mesh roll, and the degree of coloring of ethyl acetate in the ink vat and the state of the printing surface were observed.

(4) Hot water resistance Each PET and NY printed matter was coated with a urethane adhesive and laminated with a polyethylene film, left at 40 ° C. for 3 days, then each printed matter was made into a bag, and water / salad oil = 9/1
The mixture was put in, sealed and kept in hot water at 95 ° C for 40 minutes, then taken out and observed for the state of floating lami.

The judgment of each test result is ⊚: extremely good,
◯: Good, □: Medium, Δ: Slightly bad, ×: Bad.

[0064]

[Table 5]

[0065]

INDUSTRIAL APPLICABILITY According to the present invention, excellent adhesion to various plastic films, blocking resistance of printed matter and acetic acid resistance, which cannot be obtained by a conventional printing ink composition using a urethane resin as a binder, are obtained. It is possible to obtain a product having ethyl property and also having excellent hot water resistance of the laminated film.

Claims (5)

[Claims] 1. A printing ink composition comprising a polycarbodiimide compound (A). 2. A printing ink composition comprising a polycarbodiimide compound (A) and a polyurethane resin (B) containing a polymer diol, an organic diisocyanate and a chain extender. 3. A polycarbodiimide compound (A) and a polyurethane resin (B) containing a polymer diol, an organic diisocyanate and a chain extender in a weight ratio of 0.2: 99.8-9.
The printing ink composition according to claim 2, which is contained at a ratio of 0:10. 4. The polycarbodiimide compound (A) is derived from an aliphatic and / or alicyclic mono- and diisocyanate, and is reacted in a monoisocyanate: diisocyanate molar ratio of 2: 1 to 2:10. The printing ink composition according to claim 1, 2 or 3, which is obtained by the method. 5. The polycarbodiimide compound (A) is obtained by a reaction of an isocyanate compound containing a urethane prepolymer having a terminal isocyanate group obtained by a reaction of a polymeric diol and an organic diisocyanate. The printing ink composition according to claim 2 or claim 3.