KR0128372B1 - Preparation process of vehicle for uv-ray cure printing ink - Google Patents

Abstract

The preparation method for the ultraviolet ray hardened epoxy acrylate extender includes the steps of: adding 0.02 wt.% of hydroquinone as a polymerization inhibitor to 0.4 wt.% of pre-reaction materials composed of 75.0 wt.% of bisphenol A type epoxy resin (epoxy equivalent 184-194, molecular weight=360), 25.0 wt.% of acrylate and stable diethanolamine hydrochloride in a flask provided with a thermometer and an agitator; reacting the reactants under inert gas of N2 at 100-105 degrees centigrade for 7-8 hours; cooling the mixture having acidity of less than 1 to about 60 degrees centigrade; and adding 14.0 wt.% of 1,6-hexanediol diacrylate as a viscosity regulator to control the viscosity of the product at 500-700poise (Brook-field Viscometer, 25 degrees centigrade).

Description

Method for preparing a colorant for UV-curable printing inks

The present invention relates to a method for producing a colorant for ultraviolet curing ink that can be used for printing (number and tensile) high speed printing (10,000 sheets / hour) such as banknotes and securities.

UV curable printing ink absorbs ultraviolet energy, causes photopolymerization, and cures and dries in the shortest time (within 0.1 second). It is used in various industries such as wood and furniture, floor decoration, leather processing, can or pack coating to improve production by using these advantages, and in the printing field, some offset, textile printing, printed circuit board, etc. It is applied to silk screen and high speed typography, but the type, composition, manufacturing method, and physical properties of the colorant used in these inks vary according to the characteristics of the application.

The composition of the ink is basically a colorant (pigment), a propoly, which is a colorant having an acryl group that causes a photopolymerization reaction, and is composed of a polyfunctional monomer having a secondary function and a photopolymerization initiator, and is a colorant produced by the manufacturing method of the present invention. The prepolymer was an epoxy acrylate in which an epoxy resin (epoxy equivalents 184 to 194) and acrylic acid were polymerized using a diethanolamine hydrochloride catalyst. In the conventional type printing ink, a resin or the like is dissolved or synthesized based on a dry oil or a semi-dry oil, and then modified with a solvent to prepare proper physical properties and used as a colorant. Therefore, the drying method also had to absorb oxygen in the air and oxidatively polymerize the drying method by using a desiccant such as infiltration, evaporation method or metal salt. The surface of the printed material requires a long drying time and a large amount of time and space for the subsequent loading or printing process, resulting in a decrease in productivity. In particular, the solvents generated during the drying process are diffused into the atmosphere. Many problems have occurred in hygiene.

In order to solve such a conventional printing ink defect, an ultraviolet curable printing ink is disclosed in Japanese Patent Application Laid-Open No. 53-115307 (ultraviolet curing printing ink composition), Japanese Laid-Open Patent Office 52-152306 (ultraviolet curing printing ink composition), and Japan Special Printing Corporation It is known as 51-84034 (ultraviolet curing printing ink), Japanese specialty publication 48-26843 (ultraviolet drying printing ink), and these inks are used as printing inks for offset, silk screen, and typography. The urethane acrylate developer prepared by reacting fatty acid and isocyanate compound with acrylic acid or methacrylic acid is used, and the ink known by German patent 240638 (SICPA Holding SA, Switzerland) is a pentaerythritol tetraacrylate and 1.6, which is not a prepolymer as a colorant. Monomers such as hexane diol diacrylate or NN-dimethyl-3-oxo-butyl acrylamide And a condensation product prepared by reacting a reaction product of formaldehyde (molar ratio 3: 1) with 2-hydroxyethyl acrylate or hydroxy pentaerythritol triacrylate and toluene diisocyanate (molar ratio 1: 1). As used as is different from the one developed in the present invention.

Black ink using carbon black pigment in UV curable ink manufacture absorbs ultraviolet rays when the pigment itself absorbs ultraviolet rays, thus reducing the photopolymerization reaction of the photoinitiator and the prepolymer colorant. Compared to the slower curing rate than 50%. Therefore, it is necessary to increase the content of photoinitiator, but above a certain content (about 15%), there is no increase of the photoinitiation effect due to the increase of photoinitiator, which is rather expensive due to insufficient cured film and an unpleasant odor. The suitability may be improved by using special black 250 and Corax P (trade name: Degussa Co., Ltd.) or carbon black pigment surface-modified with a rosin metal salt known from Ilso 52-8040. Among such ultraviolet curable inks, black ink is the most difficult. In particular, high-speed printing presses for banknote numbers and tension printing (10,000 sheets / hour), unlike high-speed offsets within 5 μm of ink film or silk printing with slow printing speed (3,000-4,000 / hour), harden drying and scattering prevention, etc. It has the property to be better.

However, in the present invention, even in the case of using a general carbon black pigment, which is not an ultraviolet curable carbon black, it is curable by using an epoxy acrylate developer prepared by polymerizing an epoxy resin and acrylic acid having excellent curability and film adhesion in order to improve the curability of the ink. In addition, it was possible to improve the curability of the UV curable type ink suitable for high speed printing by selecting or using a multifunctional monomer and a high activation initiator alone or in combination as a photoinitiator.

The following is a description of a method for producing an epoxy acrylate as a developer of the invention.

EXAMPLE

Diethanol as a catalyst in 75.0 wt /% bisphenol A type epoxy resin (epoxy equivalent 184-194, molecular weight 350) and 25.0 wt /% acrylic acid mixture 100 parts by weight (weight ratio: below) in a four-necked flask equipped with a thermometer and a stirrer. 0.4 parts of amine hydrochloride and 0.02 parts of hydroquinone were added as a polymerization inhibitor, and reacted at 105 ° C. under inert gas (N ₂ ) for 8 hours to reach an acid value of 1 or less. About 14.0 parts of 1.6 hexanediol diacrylate was mixed to prepare a colorant having a viscosity of 700 poise (brook-field viscometer 25 ° C.).

Epoxy resins that can be used in the preparation of the above-mentioned colorants include bisphenol A and noblock alicyclic systems having epoxy equivalents and molecular weights different from those used in the present invention, and acrylic acid is methacrylic acid and catalyst is inorganic alkali carbonate. . Tertiary amines, phosphines, triethylbenzyl ammonium chloride, and potassium hydroxide of organometallic salts of lithium octanoate organic compounds. The reaction temperature is preferably 100-105 占 폚 and the reaction time is 7-8 hours.

The following is a description of the UV-curable letterpress ink (number, tensile) manufacturing method using the above-described colorant of the present invention.

The ink composition is 40 to 50 wt /% of the above-described colorant of the present invention and 6 to 12 wt /% of the trifunctional pentaerythritol triacrylate, which is a multifunctional monomer, for the composition of the ink material, and a difunctional dipentyrethitol helcyclyl. Rate 8-12wt /%, 10-15wt /% aluminum hydroxide for controlling ink viscoelasticity and anti-scattering, 3-10wt / of 2-methy1-1- (4- (mathylthio) pheny1) -2-morpholinopropanone-1 as photoinitiator % And colored pigments, carbon black for number printing ink, and red ink red B for tensile printing ink were added at 10 to 15 wt /%, respectively, and mixed in a stirrer, and then the size of the ink particles was reduced to 10 μm or less on a three roll mill. It is ground five times to manufacture ink.

As the black carbon black pigment, Printex 35,45,44,60, L0080 and the like are used, and as the red pigment, the bone red B, the simulated thread, etc. are used alone or in combination to adjust the color.

Example 1

Inkjet Ink Composition for Numbers (wt%)

Carbon Black (Printex 55) 12.0

Epoxy Acrylic Lake (Dyeing Agent) 44.0

Pentaerythritol triacrylate 7.0

Dipentaerythrite hexaacrylate 12.0

Aluminum hydroxide 15.0

2-Methyl-1- (4- (methylthio) phenyl) -210.0

-morpholinopropanone-1

100.0

Example 2

Inkjet Ink Composition for Numbers (wt%)

Carbon Black (Printex 60) 7.0

Carbon black (Loo80) 08.0

Epoxy acrylate (coloring agent) 42.0

Pentaerythritol triacrylate 7.0

Dipentaerythritol hexaacrylate 12.0

Aluminum hydroxide 15.0

2-Methyl-1- (4- (methylthio) phenyl) -2

-morpholinopropanone-19.0

100.0

Example 3

Red Ink Composition for Tension (wt%)

Simulamax Red 2.0

Bon red B10.0

Disazojero 2.0

Epoxy acrylate (coloring agent) 50.0

Pentaerythritol triacrylate 10.0

Dipentaerythritol hexaacrylate8.0

Aluminum hydroxide 15.0

2-Methyl-1- (4- (methylthio) phenyl) -2

-morpholinopropanone-13.0

100.0

Example 1

Blue Ink Composition (wt%)

Cyanine Blue 10.0

Epoxy acrylate (coloring agent)

Pentaerythritol triacrylate9.0

Dipentaerythritol hexaacrylate 12.0

Aluminum hydroxide 15.0

2-Methyl-1- (4- (methylthio) phenyl) -2

-morpholinopropanone-16.0

100.0

Example 1

Yellow Ink Composition (wt%)

Disazoello10.0

Epoxy acrylate (coloring agent)

Pentaerythritol triacrylate 10.0

Dipentyreitol hexaacrylate 12.0

Aluminum hydroxide 15.0

2-Methyl-1- (4- (methylthio) phenyl) -2

-morpholinopropanone-15.0

100.0

Example 6

In Examples 1, 2, 3, 4 and 5, instead of dipentaerythritol hexaacrylate, thifentaerythritol monohydroxy pentaacrylate is used.

Example 7

In Examples 3, 4 and 5, 1-Hydroxy cyclohexyl phenyl ketone is used instead of 2-Methyl-1- (4- (methylthio) phenyl) -2-morpholinopropanone-1.

The physical properties of the ink prepared by the above method were the taek 160-210 (32 ℃, 30sec 50m / min) yield value 1500-2500 (dyne / ㎠, 25 ℃), the storage stability was good, UV curing device 120w / imch, mercury The printing experiments on the printing press (Super Numerota 212) with a printing speed of 10,000 sheets / hour showed good printing aptitudes such as transferability, printing effect, curing property, and scattering prevention property.

Claims (1)

0.4 parts by weight of diethanolamine hydrochloride as a catalyst, 0.02 parts by weight of polymerization inhibitor to 100 parts by weight of acrylic acid mixture of 75.0 wt% epoxy resin (epoxy equivalent 184-194, molecular weight 360) acrylic acid 25.0 wt% After the reaction was carried out at 100 to 105 ° C. for 7 to 8 hours under inert water (N ₂ ), when the acid value reached 1 or less, the reaction was terminated and cooled to about 60 ° C., and then 1.6hexanediol diacrylate was used as a viscosity adjusting yo. Method for producing a colorant for ultraviolet purification type printing ink characterized in that the mixing.