JP6477142B2 - Gravure ink composition - Google Patents

Description

  The present invention relates to a gravure ink composition, and more specifically, a plate-fogging property on a printing press, an impression cylinder stain property, ink aging stability, and a black color having good density, blocking resistance, and adhesiveness of a printed matter. The present invention relates to a gravure ink composition.

  In general, in a gravure ink composition, it is known that it is difficult to stably disperse a pigment at a high concentration, which causes various problems with respect to stability over time and stability on a printing press. For example, a dispersion containing pigments composed of fine particles is likely to cause defects such as plate fog that slips through the doctor even in the non-image area of the cylinder and deposits on the substrate, and reaggregates over time. , Defects such as generation of residues in ink cans and streaks during printing occur.

  Carbon black is widely used as a black colorant for gravure ink compositions because it has advantages in chemical resistance, optical properties, and the like. However, since carbon black is a fine particle (about 10 to 100 nm), it has a remarkably strong agglomeration force and is difficult to disperse in a medium. The above problem appears remarkably.

  Therefore, improvement is tried by selection of a pigment like patent document 1 or 2. FIG. However, in the gravure ink composition, examination was insufficient.

  Patent Document 3 describes a printing ink composition containing carbon black and a polyurethane urea resin having an amine value of 0.5 to 40 mg KOH / resin 1 g and having an amino group at the terminal. Further, in Non-Patent Document 1, there is a description that carbon black improves wettability with a vehicle and increases dispersibility as the functional group represented by pH is increased. However, it was not possible to solve the problem only by examining the pH of carbon black.

Japanese Patent No. 424199 Japanese Patent Laid-Open No. 7-316481 Japanese Patent No. 5273280

Carbon Black Handbook, April 15, 1995, Third Edition, P17, 18, 270, 271

  It is an object of the present invention to provide a black gravure ink composition having good plate fog, impression cylinder stain resistance, ink aging stability, and good print density, blocking resistance and adhesion.

  As a result of intensive studies in view of the above circumstances, the present inventors have a pH value of 2 to 4, a primary particle size of 40 to 60 nm, and an oil absorption amount (OAN) limited to 65 to 100 ml / 100 g. Printing ink composition containing carbon black, amine-terminated polyurethane urea resin, and organic solvent has a plate fog, impression cylinder stain, ink aging stability, and density / blocking resistance of printed matter. It discovered that adhesiveness was favorable and came to this invention.

That is, the present invention
And carbon black, and organic amine ends, an amine value, and polyurethane urea resin is a 2~12mgKOH / g, a gravure ink composition containing an organic solvent,
Carbon black is the following (1)-(3), It is related with the gravure ink composition characterized by the above-mentioned.
(1) The average primary particle diameter is 40 to 60 nm.
(2) Oil absorption is 65 to 100 ml / 100 g.
(3) The pH value is 2-4.

Furthermore, the present invention relates to the gravure ink composition, wherein the polyurethane urea resin is characterized by the following (1) and (2).
(1) Polyurethane urea resin
This is a polyurethane urea resin obtained by reacting a urethane prepolymer obtained by reacting a polyol with a diisocyanate compound and then reacting with a hydroxyl dialkylamine compound, and further with an organic diamine.
(2) The hydroxyl dialkylamine compound is one or more compounds selected from diethylaminoethanol, dimethylaminoethanol, dipropylaminoethanol, and dibutylaminobutanol.

  Furthermore, this invention relates to the printed matter formed by apply | coating the said gravure ink composition to a printing base material.

  According to the present invention, it has become possible to provide a black gravure ink composition having good plate fogging, impression cylinder stain resistance, ink aging stability, and good print density and adhesion.

  Hereinafter, the gravure ink composition of the present invention will be described.

  Carbon black used as a black colorant in the gravure ink composition of the present invention has a pH value of 2 to 4 and is acidic. Usually, carbon black having a pH of 6.5 or less is subjected to surface oxidation treatment with various oxidizing agents. As the oxidation treatment method, for example, gas phase treatment with air, NOx, oxygen, ozone or the like, and further potassium dichromate. And liquid phase treatment with hydrogen peroxide, sodium hypochlorite, nitric acid and the like. The carbon black in the present invention may be of any kind as long as the pH value is 2 to 4. In general, when there are many acidic functional groups on the surface of carbon black produced by the surface oxidation treatment, the pH decreases.

  If the pH value of the carbon black is 2 to 4, the plate fogging property is good, and the impression cylinder stain and the ink stability over time are good. The pH value was determined by adding 100 ml of pure water to 10 g of carbon black, heating at 95 ° C. for 15 minutes using a water bath, cooling to room temperature, removing the supernatant, and adjusting the pH of the sediment at the bottom to a pH meter. It measured using (Horiba Seisakusho D-51T).

  Carbon black in the present invention has a primary particle size in the range of 40 to 60 nm and an oil absorption (OAN) in the range of 65 to 100 ml / 100 g. If the primary particle size is smaller than 40 nm or the oil absorption (OAN) is smaller than 65 ml / 100 g, the carbon structure will be small and high concentration will be shown. The body slips through and the fogging property becomes worse. On the contrary, if the primary particle diameter is larger than 60 nm or the oil absorption (OAN) is larger than 100 ml / 100 g, the plate covering property is improved, but the printed matter density is lowered. In the present invention, since acid-treated carbon black is combined with amine-terminated polyurethane urea resin, dispersibility is further improved, and carbon black having an equivalent primary particle size and oil absorption amount that is not acid-treated is obtained. Compared to high concentration.

  The average primary particle diameter is a value obtained by observing carbon black particles with an electron microscope and calculating from the arithmetic average diameter. The oil absorption amount (OAN) indicates a value obtained in accordance with JIS K6217-4 or ASTM D2414.

  In the present invention, a polyurethane urea resin is contained as a binder resin, and the polyurethane urea resin has an amine terminal. Due to the affinity between the amino group at the end of the polyurethane urea resin and the acidic functional group on the surface of the carbon black, it is presumed that the plate covering property and the impression cylinder stain property are improved.

  The polyurethane urea resin in the present invention is obtained by reacting a urethane prepolymer having an isocyanate group at the terminal obtained by reacting a polyol and a diisocyanate compound with an organic diamine. That is, in the polyurethane urea resin synthesis method, a polyol and a diisocyanate compound are first used as a prepolymer reaction, and if necessary, an inert solvent for an isocyanate group is used. A urethane prepolymer having an isocyanate group at the terminal is produced by reacting at a temperature, and then the urethane prepolymer and an organic diamine are reacted at 10 to 80 ° C. as a chain extension reaction. The end points of the prepolymer reaction and chain extension reaction are determined by viscosity measurement, NCO peak by IR measurement, amine value measurement by titration, and the like.

  In the present invention, the amine value of the polyurethaneurea resin is preferably 2 to 12 mgKOH / g. When the amine value is within this range, the affinity with the acidic functional group on the surface of the carbon black is increased, the plate fog property and the impression cylinder stain property are improved, and the ink stability with time and the adhesion of the coating film are good. It is. More preferably, the amine value is 6 to 12 mgKOH / g.

  As the polyol used for the polyurethane urea resin in the present invention, various known polyester polyols, polyether polyols, polycaprolactones, and the like can be used, and one or more of them may be used in combination. Examples of the polyester polyol include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3-propanediol, 2-ethyl-2butyl-1,3propanediol, 1, 3-butanediol, 1,4-butanediol, neopentyl glycol, pentanediol, 3-methyl-1,5-pentanediol, hexanediol, octanediol, 1,4-butynediol, 1,4-butylenediol, Saturated or unsaturated such as diethylene glycol, triethylene glycol, dipropylene glycol, glycerin, trimethylolpropane, trimethylolethane, 1,2,6-hexanetriol, 1,2,4-butanetriol, sorbitol, pentaesitol Low molecular weight poly 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 Polyester polyols obtained by dehydrating condensation or polymerization of polyvalent carboxylic acids such as pyromellitic acid or their anhydrides, cyclic ester compounds such as polycaprolactone, polyvalerolactone, poly (β-methyl-γ-valerolactone) And polyester polyols obtained by ring-opening polymerization of lactones such as Examples of polyether polyols include polymers or copolymers such as methylene oxide, ethylene oxide, propylene oxide, and tetrahydrofuran. It is preferable to use a polyester polyol and a polyether polyol in combination.

  As the diisocyanate compound used in the polyurethane urea resin in the present invention, various known diisocyanates of aromatic, aliphatic or alicyclic can be used. For example, 1,5-naphthylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-dibenzyl isocyanate, dialkyldiphenylmethane diisocyanate, tetraalkyldiphenylmethane diisocyanate, 1,3- Phenylene diisocyanate, 1,4-phenylene diisocyanate, tolylene diisocyanate, butane-1,4-diisocyanate, hexamethylene diisocyanate, isopropylene diisocyanate, methylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4- Trimethylhexamethylene diisocyanate, cyclohexane-1,4-diisocyanate, xylylene diisocyanate Isophorone diisocyanate, lysine diisocyanate, dicyclohexylmethane-4,4′-diisocyanate, 1,3-bis (isocyanatemethyl) cyclohexane, methylcyclohexane diisocyanate, m-tetramethylxylylene diisocyanate, and carboxyl groups of dimer acid were converted to isocyanate groups. Dimer isocyanate is a typical example. These can be used alone or in admixture of two or more. Isophorone diisocyanate, tolylene diisocyanate, and 4,4'-diphenylmethane diisocyanate are preferred.

  Examples of the organic diamine used in the polyurethane urea resin in the present invention include ethylene diamine, propylene diamine, hexamethylene diamine, isophorone diamine, and dicyclohexylmethane-4,4'-diamine. N- (2-hydroxyethyl) ethylenediamine, N- (2-hydroxyethyl) propyldiamine, N- (2-hydroxyethyl) propylenediamine, N, N-bis (2-hydroxyethyl) ethylenediamine, N, N Has a hydroxyl group in the molecule, such as -bis (2-hydroxyethyl) propylenediamine, 2-hydroxypropylethylenediamine, N, N-bis (2-hydroxypropyl) ethylenediamine, N, N-bis (2-hydroxypropyl) ethylenediamine Amines can also be used. When amines having a hydroxyl group in the molecule are used, the hydroxyl group incorporated in the urethane urea resin interacts with the acidic functional group of carbon black, so that a more stable pigment dispersion is obtained and the plate fogging property is improved. These organic diamines can be used alone or in admixture of two or more, with isophorone diamine and N- (2-hydroxyethyl) ethylene diamine being preferred.

  The organic solvent used in the synthesis of the polyurethane urea resin in the present invention includes a mixed solvent of an ester solvent and an alcohol solvent. Examples of ester solvents include ethyl acetate, n-propyl acetate, isopropyl acetate, isobutyl acetate, propylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, and alcohol solvents include methanol, ethanol, n-propanol, isopropanol, It is preferable to use a known solvent such as an alcohol solvent such as n-butanol, propylene glycol monoethyl ether, propylene glycol monomethyl ether.

  In the prepolymer reaction, an amino group can be introduced into the prepolymer by adding a hydroxyldialkylamine compound having one hydroxyl group in the molecule as long as an isocyanate group remains at the terminal. More preferably, after the reaction between the polyol and the diisocyanate compound, the hydroxyl dialkylamine compound is reacted. Examples of the hydroxyl dialkylamine compound include dimethylaminomethanol, dimethylaminoethanol, dimethylaminopropanol, dimethylaminobutanol, diethylaminomethanol, diethylaminoethanol, diethylaminopropanol, diethylaminobutanol, dipropylaminomethanol, dipropylaminoethanol, dipropylamino. Propanol, dipropylaminobutanol, dibutylaminoethanol, dibutylaminopropanol, dibutylaminobutanol, 1- (2-hydroxymethyl) pyrrolidine, 1- (2-hydroxyethyl) pyrrolidine, 1-methyl-2-piperidinemethanol, 2-hydroxy Ethyl morpholine is mentioned. Of these, diethylaminoethanol, dimethylaminoethanol, dipropylaminoethanol, and dibutylaminobutanol are more preferable. When a tertiary amine is appropriately introduced as compared with the case where only the terminal is a primary or secondary amine, the strength of the interaction between the resin and the acidic carbon is moderately controlled, and the temporal stability and the plate fogging property are improved.

  Further, a catalyst can be used for the prepolymer reaction. Examples of catalysts that can be used include tertiary amine catalysts such as triethylamine and dimethylaniline; metal catalysts such as tin and zinc. These catalysts are usually used in the range of 0.001 to 1 mol% with respect to the polyol.

  A reaction terminator may be used for the chain extension reaction. Examples of the reaction terminator include dialkylamines such as di-n-butylamine, monoethanolamine, diethanolamine, 2-amino-2-methyl-1-propanol, tri (hydroxymethyl) aminomethane, 2-amino. Amines having a hydroxyl group such as 2-ethyl-1,3-propanediol can also be used. Furthermore, monoamine type amino acids such as glycine, alanine, glutamic acid, taurine, aspartic acid, aminobutyric acid, valine, aminocaproic acid, aminobenzoic acid, aminoisophthalic acid, sulfamic acid and the like can also be mentioned.

  In addition to the polyurethane urea resin, the binder resin of the gravure ink composition of the present invention can be used in combination with resins used in general inks, paints, recording agents and the like. For example, polyurethane resin (excluding polyurethane urea resin), vinyl chloride-vinyl acetate copolymer resin, chlorinated polypropylene resin, ethylene-vinyl acetate copolymer resin, vinyl acetate resin, polyamide resin, nitrocellulose resin, acrylic resin, polyester Examples thereof include resins, alkyd resins, polyvinyl chloride resins, ketone resins, rosin or rosin derivatives, cyclized rubber, chlorinated rubber, butyral, and petroleum resins. The resins can be used alone or in admixture of two or more. The resin content (in terms of solid content) is preferably 4 to 25% by weight, more preferably 6 to 20% by weight, based on the total weight of the ink.

  The gravure ink composition of the present invention is produced by dispersing carbon black in an organic solvent with a binder resin or the like using a dispersing machine, and mixing the resulting pigment dispersion with a binder resin, various additives, an organic solvent, or the like. it can. As the disperser, generally used, for example, a roller mill, a ball mill, a pebble mill, an attritor, a sand mill and the like can be used. The particle size distribution of the pigment in the pigment dispersion is adjusted by appropriately adjusting the size of the grinding media of the disperser, the filling rate of the grinding media, the dispersion treatment time, the discharge speed of the pigment dispersion, the viscosity of the pigment dispersion, etc. be able to.

  In order to disperse carbon black stably, the binder resin alone can be dispersed, but a pigment dispersant can also be used in combination to disperse the pigment stably. As the pigment dispersant, anionic, nonionic, cationic, amphoteric surfactants can be used. The pigment dispersant is preferably contained in an amount of 0.05% by weight or more with respect to the total weight of the printing ink composition from the viewpoint of ink stability and 10% by weight or less from the viewpoint of suitability for lamination. Furthermore, it is more preferable that it is contained in the range of 0.1 to 3% by weight.

  Carbon black is preferably contained in an amount sufficient to ensure the concentration and coloring power of the gravure ink composition, that is, in a proportion of 1 to 30% by weight based on the total weight of the gravure ink composition. These carbon blacks can be used alone or in combination of two or more.

  In addition, additives such as leveling agents, antifoaming agents, waxes, silane coupling agents, plasticizers, light stabilizers, infrared absorbers, ultraviolet absorbers, fragrances, and flame retardants may be included as necessary. it can.

  As the organic solvent used in the gravure ink composition in the present invention, as in the organic solvent used in the polyurethane resin, ethyl acetate, n-propyl acetate, isopropyl acetate, isobutyl acetate, propylene glycol monoethyl ether acetate, propylene Known solvents such as ester solvents such as glycol monomethyl ether acetate, alcohol solvents such as methanol, ethanol, n-propanol, isopropanol, n-butanol, propylene glycol monoethyl ether and propylene glycol monomethyl ether can be used. In recent years, there has been a demand to eliminate aromatic organic solvents such as toluene and xylene and ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone from the viewpoint of the working environment. In the gravure ink composition of the present invention, a solvent that eliminates this is preferred. Used.

  If the gravure ink composition contains bubbles or unexpectedly coarse particles, it is preferably removed by filtration or the like in order to reduce the quality of the printed matter. A conventionally well-known filter can be used.

  The viscosity of the gravure ink composition is preferably in the range of 10 mPa · s or more from the viewpoint of preventing the pigment from settling and being appropriately dispersed, 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 gravure ink composition in the present invention is diluted with a diluent solvent to a viscosity and concentration suitable for printing, and is supplied alone or mixed to each printing unit of the gravure printing machine.

  As a substrate to which the gravure ink composition of the present invention can be applied, polyolefin such as polyethylene or polypropylene, polyethylene terephthalate, polyester such as polycarbonate or polylactic acid, polystyrene resin such as polystyrene, AS resin or ABS resin, nylon, polyamide, There are various films of polyvinyl chloride, polyvinylidene chloride, cellophane, paper, aluminum foil, etc., or a film or sheet made of a composite material thereof. These substrates may be subjected to vapor deposition coating treatment and / or coating treatment such as polyvinyl alcohol on the surface of a metal oxide, for example, GL- manufactured by Toppan Printing Co., Ltd. in which aluminum oxide is vapor deposited on the substrate surface. Examples include AE and IB-PET-PXB manufactured by Dai Nippon Printing Co., Ltd. Further, those treated with additives such as an antistatic agent and an ultraviolet ray inhibitor, and those obtained by subjecting the surface of the substrate to corona treatment or low temperature plasma treatment can be used as necessary.

  The printed matter in the present invention is obtained by applying a gravure ink composition using a gravure printing method, and drying and fixing by oven drying. The drying temperature is usually about 40 to 60 ° C.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, this invention is not limited to these Examples. In the present invention, “parts” and “%” represent “parts by weight” and “% by weight” unless otherwise noted.

  The hydroxyl value was acetylated with an excess of an acetylating reagent and the amount of hydroxyl group in 1 g of resin calculated by back titrating the remaining acid with alkali was converted to mg of potassium hydroxide. The value is a value obtained according to JIS K0070. The number average molecular weight was determined as a polystyrene-converted molecular weight by measuring the molecular weight distribution using a GPC (gel permeation chromatography) apparatus. Tetrahydrofuran was used as a measurement solvent for GPC. The amine value is the number of mg of potassium hydroxide equivalent to the equivalent of hydrochloric acid required to neutralize the amino group contained in 1 g of resin. The method for measuring the amine value is as follows.

[Method for measuring amine value]
Weigh accurately 5-10 g of sample. (Sample amount: S (weight of solid content) g) Toluene 25 mL and n-butanol 25 mL are added to a precisely weighed sample and sufficiently dissolved. 30 mL of methanol is added thereto, and potentiometric titration is performed with a 0.1 mol / L aqueous hydrochloric acid solution (titer: f). The amine value was calculated | required by the following (Formula 1) using the titration amount (AmL) at this time.

Formula 1
Amine value = (A × f × 0.1 × 56.108) / S [mgKOH / g]

[Synthesis of polyurethane urea resin varnish]
[Synthesis Example 1]
In a four-necked flask equipped with a stirrer, a thermometer, a reflux condenser and a nitrogen gas inlet tube, a poly (3-methyl-1,5-pentaneadipate) diol having a molecular weight of 2000 (PMPA2000: hydroxyl value 55.1 mgKOH / g) 28.7 parts, molecular weight 2000 poly (1,2-propylene glycol) (PPG2000: hydroxyl value 55.1 mgKOH / g) 28.7 parts, isophorone diisocyanate 12.5 parts, 2-ethylhexanoate tin (II) 0 0.03 part and 30 parts of ethyl acetate were charged and reacted at 90 ° C. for 3 hours under a nitrogen stream to obtain 100 parts of a terminal isocyanate prepolymer solution having a solid content of 70%. Next, a mixture of 3.4 parts of isophorone diamine, 72.7 parts of ethyl acetate and 68.5 parts of isopropyl alcohol as a chain extender was gradually added to the resulting solution of the terminal isocyanate prepolymer at room temperature, The mixture was reacted at 50 ° C. for 1 hour to obtain a polyurethane urea resin varnish (R01) having a solid content of 30.0% and an amine value not detected (amine value 0.0 mgKOH / g).
[Synthesis Example 2]
In the same manner as in Synthesis Example 1, a poly (3-methyl-1,5-pentaneadipate) diol (PMPA2000: hydroxyl value) having a molecular weight of 2000 was added to a four-necked flask equipped with a stirrer, thermometer, reflux condenser and nitrogen gas introduction tube. 58.7 mgKOH / g) 28.7 parts, molecular weight 2000 poly (1,2-propylene glycol) (PPG2000: hydroxyl value 55.1 mgKOH / g) 28.7 parts, isophorone diisocyanate 12.5 parts, 2-ethylhexane 0.03 part of tin (II) acid and 30 parts of ethyl acetate were charged and reacted at 90 ° C. for 3 hours under a nitrogen stream to obtain 100 parts of a terminal isocyanate prepolymer solution having a solid content of 70%. Next, a solution of the obtained terminal isocyanate prepolymer was gradually added at room temperature to a mixture of 4.9 parts of isophoronediamine, 74.9 parts of ethyl acetate and 70.0 parts of isopropyl alcohol as a chain extender. The mixture was reacted at 50 ° C. for 1 hour to obtain a polyurethane urea resin varnish (R02) having a solid content of 30.0% and an amine value of 2.0 mgKOH / g.

[Synthesis Examples 3 to 13]
Polyurethane urea resin varnishes (R03 to R13) were obtained in the same manner as in Synthesis Example 2 with the parts preparation ratio shown in Table 1-1.
[Synthesis Example 14]
In a four-necked flask equipped with a stirrer, a thermometer, a reflux condenser and a nitrogen gas inlet tube, a poly (3-methyl-1,5-pentaneadipate) diol having a molecular weight of 2000 (PMPA2000: hydroxyl value 55.1 mgKOH / g) 40.8 parts, molecular weight 2000 poly (1,2-propylene glycol) (PPG2000: hydroxyl value 55.1 mgKOH / g) 13.6 parts, isophorone diisocyanate 14.8 parts, 2-ethylhexanoic acid tin (II ) 0.03 part and 30 parts of ethyl acetate were charged and reacted at 90 ° C. for 3 hours under a nitrogen stream to obtain 99.2 parts of a terminal isocyanate prepolymer solution. Next, 0.8 part of diethylaminoethanol was added, and the reaction was further performed at 90 ° C. for 3 hours to obtain 100 parts of a solution of a terminal isocyanate prepolymer (partially terminal tertiary amine) having a solid content of 70%.
Next, 5.8 parts of isophoronediamine, 0.6 part of N- (2-hydroxyethyl) ethylenediamine, 76.9 parts of ethyl acetate, and 71.3 parts of isopropyl alcohol as a chain extender were added to the resulting solution of the terminal isocyanate prepolymer. The mixture was gradually added at room temperature and then reacted at 50 ° C. for 1 hour to obtain a polyurethane urea resin varnish (R14) having a solid content of 30.0% and an amine value of 9.9 mgKOH / g.

[Synthesis Examples 15 to 25]
In the same manner as in Synthesis Example 14, polyurethane urea resin varnishes (R15 to 25) were obtained according to the formulation shown in Table 1-1.
In Table 1-1, PMPA2000 is a poly (3-methyl-1,5-pentaneadipate) diol having a molecular weight of 2000 (hydroxyl value 55.1 mgKOH / g), and PMPA5000 is a poly (3-methyl-1,5-pentane having a molecular weight of 5000. Adipate) diol (hydroxyl value 22.4 mgKOH / g), PPG700 is poly (1,2-propylene glycol) having a molecular weight of 700 (hydroxyl value 160.3 mgKOH / g), PPG2000 is poly (1,2-propyleneglycol having a molecular weight of 2000 ) (Hydroxyl value 55.1 mgKOH / g), DEAE is diethylaminoethanol, DMAE is dimethylaminoethanol, DPAE is dipropylaminoethanol, DBAB is dibutylaminobutanol, IPDI is isophorone diisocyanate, IPDA is i Isophoronediamine, AEA is N-(2-hydroxyethyl) ethylenediamine, IbpA is a iminobispropylamine, EA is ethyl acetate, IPA represents isopropyl alcohol.

[Carbon black]
Carbon black of C01 to C11 shown in Table 1-2 is used. The pH value, primary particle diameter, and oil absorption amount (OAN) of each carbon black are shown in Table 1-2. The primary particle size and oil absorption (OAN) are the values described in the catalog. The pH value is 100 ml of pure water added to 10 g of carbon black and heated at 95 ° C. for 15 minutes using a water bath. After cooling to room temperature, the supernatant was removed and the pH of the sediment at the bottom was measured using a pH meter (D-51T manufactured by Horiba, Ltd.).

  In Table 1-2, Raven1080Ultra (Raven1080U) and Raven500 are manufactured by Aditya Birla, Nerox305, Special Black 100 and Printex35P are manufactured by Orion Engineered Carbons, and MA14, MA220 and MA100 are manufactured by Mitsubishi Chemical Co., Ltd. And Seast V are carbon black manufactured by Tokai Carbon Co., and REGAL99R is carbon black manufactured by Cabot.

[Preparation of gravure ink composition]
[Example 1]
10 parts of carbon black (C03: carbon black MA14 manufactured by Mitsubishi Chemical Corporation), 20 parts of polyurethane urea resin varnish (R04), 5 parts of isopropyl alcohol and 5 parts of n-propyl acetate were stirred and mixed in a sand mill, and then polyurethane urea 15 parts of resin varnish (R04), 35 parts of a mixed solution of isopropyl alcohol and ethyl acetate in a ratio of 40:60, and 10 parts of isopropyl alcohol: n-propyl acetate mixed solvent (weight ratio 25:75) are mixed to prepare a gravure ink composition. A product (Ink01) was obtained.

[Examples 2 to 30] [Comparative Examples 1 to 9]
In the same manner as in Example 1, gravure ink compositions (Ink02 to Ink39) were obtained at the charging ratios described in Table 2-1 and Table 2-2.

  The following tests were conducted using the obtained gravure ink composition. The evaluation results are shown in Table 2-1 and Table 2-2.

<Ink aging stability>
The obtained gravure ink compositions Ink01 to Ink39 were sampled in glass bottles, sealed and stored at 40 ° C. for 7 days, and the presence or absence of precipitates was confirmed and the difference in viscosity before and after charging was evaluated. Viscosity was measured using Zahn Cup # 4 manufactured by Kouaisha.
◎ ・ ・ ・ Zahn cup (# 4) Viscosity increased or decreased within 1 second and no precipitate was observed.
〇 ・ ・ ・ Zahn cup (# 4) viscosity is less than 3 seconds thickening or thinning, and no precipitation is observed.
Δ: Zahn cup (# 4) viscosity is less than 3 seconds thickening or thinning, and some precipitation is observed.
X: Zahn cup (# 4) viscosity increased or decreased for 3 seconds or more, or a large amount of precipitate was generated.
◎, ○, and Δ are ranges where there is no practical problem.

<Plate fog (plate fog / streak (30 minutes))>
To 100 parts of each of the obtained gravure ink compositions Ink01 to Ink39, 50 parts of isopropyl alcohol: n-propyl acetate mixed solvent (weight ratio 25:75) was mixed to obtain a diluted ink, which was a gravure with a circumference of 600 mm. A ceramic doctor TS150F-Sic-NN manufactured by Tokyo Seisakusho Co., Ltd. was set in a cylinder (manufactured by Toyo FPP Co., Ltd.) at a doctor pressure of 2.0 kg / cm ² , and was idled at a printing speed of 200 m / min. Went.
◎ ... No streaking or plate fogging observed from the doctor side.
〇… Streaks and plate fog linked to the doctor stroke are observed from the doctor side, but no streaks and plate fog are observed in the plate surface observation with the strobe from the front of the unit.
Δ: Streaks and fogging are slightly observed in the plate surface observation with a strobe from the front of the unit.
X: Occurrence of streaks and plate fogging is considerably observed in the plate surface observation with a strobe from the front of the unit.
<Plate fog (plate fog / streak (60 minutes))>
To 100 parts of each of the obtained gravure ink compositions Ink01 to Ink39, 50 parts of isopropyl alcohol: n-propyl acetate mixed solvent (weight ratio 25:75) was mixed to obtain a diluted ink, which was a gravure with a circumference of 600 mm. A ceramic doctor TS150F-Sic-NN manufactured by Tokyo Seisakusho Co., Ltd. was set in a cylinder (manufactured by Toyo FPP Co., Ltd.) at a doctor pressure of 2.0 kg / cm ² , and was idled at a printing speed of 200 m / min. Went.
◎ ... No streaking or plate fogging observed from the doctor side.
〇… Streaks and plate fog linked to the doctor stroke are observed from the doctor side, but no streaks and plate fog are observed in the plate surface observation with the strobe from the front of the unit.
Δ: Streaks and fogging are slightly observed in the plate surface observation with a strobe from the front of the unit.
X: Occurrence of streaks and plate fogging is considerably observed in the plate surface observation with a strobe from the front of the unit.

<Imprint stain resistance>
To 100 parts of each of the obtained gravure ink compositions Ink01 to Ink39, 50 parts of isopropyl alcohol: n-propyl acetate mixed solvent (weight ratio 25:75) was mixed to obtain a diluted ink, which was a gravure with a circumference of 600 mm. A ceramic doctor TS150F-Sic-NN manufactured by Tokyo Seisakusho Co., Ltd. is set at a doctor pressure of 2.0 kg / cm ² on a cylinder (Toyo FPP, unpatterned Bose version), and an impression cylinder rubber roll having a hardness of 70 ° is set to 2.5 kg / cm ^2. Evaluation was performed based on how the impression cylinder rubber roll was stained 30 minutes after being pressed at a printing pressure of 200 m / min and rotated at a printing speed of 200 m / min.
◎ ・ ・ ・ There is no dirt on the impression cylinder, and the impression cylinder is kept clean.
〇 ・ ・ ・ The impression cylinder is slightly stained, and the impression cylinder is light gray.
Δ: The impression cylinder is dirty and the impression cylinder is black.
X: Significant generation of impression cylinder stains was observed, and ink was deposited on the impression cylinder.
◎, ○, and Δ are ranges where there is no practical problem.

  50 parts of isopropyl alcohol: n-propyl acetate mixed solvent (weight ratio 25:75) is mixed with 100 parts of each of the obtained gravure ink compositions Ink01 to Ink39 to prepare a diluted ink, and a plate depth of 25 μm is provided. A gravure proofing machine printed on a corona-treated OPP film (Futamura Chemical Co., FOR # 20) at a speed of 40 m / min and dried at 40 to 50 ° C. to obtain a printed matter. The following tests were performed using the obtained printed matter.

<Concentration>
The density of the solid part of the printed material was measured by reflection density using an X-Rite 939 spectral densitometer manufactured by X-Rite, and evaluated by the V value.
◎ ・ ・ ・ V value is 2.2 or more ○ ・ ・ ・ V value is 2.1 or more and less than 2.2 Δ ・ ・ ・ V value is 2.0 or more and less than 2.1 × ・ ・ ・ V value is 2. Less than 0, ◯, and Δ are ranges where there is no practical problem.

<Tape adhesiveness>
One day after the printed matter was printed, cellophane tape (12 mm width) manufactured by Nichiban Co., Ltd. was affixed to the printing surface, rubbed strongly with the thumb five times, and then peeled off. Evaluation was made based on how the ink film was taken at that time.
◎ ・ ・ ・ No transition to tape ○ ・ ・ ・ Transition to tape about 25% △ ・ ・ ・ Transition to tape about 50% × ・ ・ ・ Almost the entire surface is taken ◎ 、 ○ 、 △ are practically no problem It is a range.

<Blocking resistance>
Overlay the film so that the printed surface and non-printed surface of the corona-treated OPP print are in contact with each other, apply a weight of 5 kgf / cm 2, leave it in an environment of 40 ° C. and 80% RH for 24 hours, take it out, and then remove the non-printed surface. The state of ink transfer to the ink was evaluated on a five-point scale.
◎ ・ ・ ・ 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 A, ○, Δ are ranges where there is no practical problem.

  From the evaluation results, carbon black having a pH value of 2 to 4, a primary particle diameter of 40 to 60 nm, and an oil absorption (OAN) limited to 65 to 100 ml / 100 g, and a polyurethane urea resin having an amine terminal are shown. The gravure ink compositions Ink01 to Ink30 of Examples 1 to 30 which are combinations are compared with Comparative Examples 1 to 9 gravure ink compositions Ink31 to Ink39, plate fog (30 minutes, 60 minutes), impression cylinder stains, Ink stability with time, density of printed matter, blocking resistance and tape adhesion are good. In particular, when an amine having a hydroxyl group is used as the organic diamine in the synthesis of the polyurethane urea resin, the plate fog is further improved. Further, when a hydroxyldialkylamine compound was used in the prepolymer reaction in the synthesis of the polyurethane urea resin, the temporal stability and the plate fogging property were further improved.

Claims (3)

And carbon black, and organic amine ends, an amine value, and polyurethane urea resin is a 2~12mgKOH / g, a gravure ink composition containing an organic solvent,
The gravure ink composition, wherein the carbon black is the following (1) to (3).
(1) The average primary particle diameter is 40 to 60 nm.
(2) Oil absorption is 65 to 100 ml / 100 g.
(3) The pH value is 2-4. Polyurethane urea resin is the following (1) and (2) Gravure Ink composition according to claim 1, wherein.
(1) Polyurethane urea resin
This is a polyurethane urea resin obtained by reacting a urethane prepolymer obtained by reacting a polyol with a diisocyanate compound and then reacting with a hydroxyl dialkylamine compound, and further with an organic diamine.
(2) The hydroxyl dialkylamine compound is one or more compounds selected from diethylaminoethanol, dimethylaminoethanol, dipropylaminoethanol, and dibutylaminobutanol. The printed matter formed by apply | coating the gravure ink composition of Claim 1 or 2 to a printing base material.