CS257738B1 - Pigment inks for inks - Google Patents

Abstract

Pigment preparation for printing containing by weight 60 to 90% of the pigment of formula I, 5 to 15% of calcium salts of resin acids based on abietic acid containing 5 to 25% of an alkanolamide of the general formula II, where R is a saturated or unsaturated aliphatic radical with a number of carbon atoms of 10 to 24 and n is 2 to 6 or mixtures of these alkanolamides.

Description

The present invention relates to a composition for pigmenting intaglio inks.

Pigment preparations based on organic pigments C.I. Pigment Yellow 12, C.I. Pigment Yellow 13, C.I. Pigment Blue 15: 3 and C.I. Pigment Red 57: 1. Red pigment C.I. Pigment Red 57: 1 is produced by coupling diazotized 4-aminotoluene-3-sulfoacid with 3-hydroxy-2-naphthoic acid in an alkaline medium and then converting the disodium salt of 4- (4-methyl-2-sulfobenzenazo) -3-hydroxy- 2-naphthoic acid to the calcium salt to form a azole of formula

The particles of this Red Pigmet are usually treated with abietic acid-based rosins (rosin). This gives a product suitable for the production of offset inks, but does not meet the requirements for preparations for pigmentation of intaglio inks.

A pigment preparation according to the invention comprising 60 to 90% of azolac of formula (I), 5 to 15% by weight of an alkanolamide or a mixture of alkanolamides of aliphatic acids of the general formula

R-CON - / (CH ₂ ) _n OH / ₂ (II) where R is a saturated or unsaturated aliphatic residue having a carbon number of 10 to 24 and n is 2 to 6, satisfies the requirements for pigment preparations intended for printing purposes, in particular gravure printing .

The pigment azolac of formula (1), which is present in the composition according to the invention in an amount of 60 to 90% by weight, is produced by known methods. The coupling of the diazotized 4-aminotoluene-3-sulfoacid with 3-hydroxy-2-naphthoic acid and the lacquering of the resulting product with alkaline earth salts are advantageously carried out in the presence of abietic acid-based resin soaps containing 8 to 17% by weight. calcium salts of resin acids. This product is then micronized according to the invention by milling in an aqueous suspension using, for example, bead mills, turbine dispersants and the like.

During micronization, the aggregates are destroyed as well as the mean particle size of the red pigment primary particles is reduced. Micronization must be carried out under conditions (concentration, temperature, grinding intensity, etc.) such that the resulting pigment exhibits maximum yield. However, the micronized pigment particles tend to reduce high free surface energy values by forming aggregates. Aggregates reduce the color spread of the pigment and impair the dispersibility of the product in the application environment. According to the invention, the formation of aggregates is significantly suppressed by treating the pigment particles after micronization with an adjuvant or mixture of adjuvants of formula (II). These substances can be applied in the form of a solution, for example, in ethanol, acetic acid or as an aqueous emulsion, and are added to the stirred pigment dispersion after micronization. The mixture is then stirred, optionally at an elevated temperature of up to 90 ° C, whereby the auxiliaries are adsorbed to the surface of the pigment particles. The product is finally filtered and dried in a suitable type of oven.

An advantage of the pigment preparation according to the invention is that it disperses well in the system used in the production of gravure inks, so that efficient and energy-intensive dispersing devices are not required. The pigment preparation is rich in color, since regrowth was prevented by treating the pigment particles after micronization.

In the examples, percentages are by weight.

Example 1

3.4 kg of an aqueous slurry of 15.0% dry matter (dry matter composition was 92.0% C.I. Pigment Red 57: 1 and 8.0% calcium resin acid salts) was pre-milled on a corundum rotor mill. Then the suspension was milled in a 0.6 L pearl horizontal mill filled with 0.48 L glass beads of 0.75 mm average size. The suspension was milled through three mill passes at a peripheral speed of grinding wheels of 11 mm and then diluted with 4.1 L of water. A solution of 0.045 kg of stearic acid diethanolamide and 0.035 kg of oleic acid diethanol amide in 0.35 L of ethanol was added to the diluted dispersion with stirring. The mixture was then stirred for 30 minutes at 70 ° C and filtered hot on a Btichner filter. The product was dried to constant weight at 85 ° C. A pigment preparation containing 81.2 t of C.I. Pigment Red 57: 1, 7.1% calcium salts of resin acids, 6.6 stearic acid diethanolamide and 5.1% oleic acid diethanolamide. An intaglio ink was produced using the preparation. Test prints with this color were of good quality, the determined dispersive hardness was = 12 (for prints made with a color pigmented product produced by the prior art procedure, for example, according to the AO 221 701, it was = 76).

Example2

A pigment preparation containing 79.0% C.I was produced as in Example 1:

Pigment Red 57: 1, 6.0% calcium salts of resin acids based on abietic acid and 15.0% diethanolamide palmitic acid. The preparation was well dispersible in the application environment, the proofs were of good quality in terms of spreading and shade. -

Claims (1)

SUBJECT OF THE INVENTION Pigment preparation for printing comprising 60 to 90 By weight of pigment of formula 5-15% by weight of the calcium salts of resin acids, abietic acid, characterized in that it contains 5-25% by weight of alkanolamide of formula. ^<C H _{2> N} ° ^H R - COH ^ f \ _{(CH2) n} ^H wherein R ° is a saturated or unsaturated aliphatic radical having the number of carbon atoms from 10 to 24 and n is 2 to 6, or mixtures of these alkanolamides.