CS255632B1 - Ultraviolet curable reactive composition for inks and coatings - Google Patents

Abstract

Ultraviolet-curable reactive composition for printing inks and coatings consisting by weight of 10 to 23% polyepoxyacrylate with a viscosity of 10 to 150 Pa.s, 30 to 50 4 (methacrylic esters of at least trihydric alcohols with a viscosity of 0.12 0.1 to 6.5 Pa.s, 17 to 33% unsaturated polyesters with a viscosity of 2.5 to 50 Pa.s, 0.02 to 0.08% polymerization inhibitors from the group of hydroquinone and di-tert-butyl-p-cresol, 0 to 8 S of silicone-based spreading agents, 0 to 4% polyethylene wax with a softening temperature of up to 110 °C, 0 to 14. % ethylene glycol monoethyl ether and optionally up to 20% pigments and fillers, mutual weight ratio polyepoxyacrylates:(meth)acrylic esters:unsaturated polyesters is (0.15-0.25):(0.4-0.6): :(0.22-0.38) and 1 to 10 4 photoinitiator from the group of benzophenone, benzoin, anthraquinone or their derivatives per 100% of the reactive composition added immediately before application and curing, they are cured by the action of ultraviolet radiation for a period of the order of a few tenths of a second to several seconds and is economically advantageous for applications as a printing ink or coating for prints or coatings on various substrates, where an extremely fast curing time is required.

Description

The invention relates to a composition of unsaturated resin binders and monomers of polyepoxyacrylates, unsaturated polyesters and (meth) acrylic esters of at least a trihydric alcohol with initiators, inhibitors, additives and optionally pigments for varnishes, inks and coatings and their application.

Combinations of polyepoxyacrylates with (meth) acrylic esters of polyalcohols for ultraviolet curing coatings are known and described, for example, in US Pat. 4,071,425 and 'Brit. U.S. Pat. No. 1,476,528, which, however, provide coatings with insufficient elasticity at sufficiently high reactivity. Combinations of polyepoxyacrylates with unsaturated polyesters for ultraviolet curing are also known, as described, for example, in NSR Pat. No. 2,244,171, but which do not have sufficient curing speed.

For this reason, it has been an object of the present invention to provide compositions for this curing process that have a sufficiently high reactivity to allow rapid cure in accordance with high speeds of, for example, modern printing machines, while at the same time cured coatings have good mechanical properties, especially suppleness and hardness.

It has been found that these properties, i.e. the high reactivity and at the same time the good mechanical properties of the cured coatings, are achieved by compositions of polyepoxyacrylates with (meth) acrylic esters of at least trihydric alcohols and unsaturated polyesters in which these components are present in , 15-0,25):

: (0.40-0.60): (0.22-0.38).

Accordingly, the present invention provides an ultraviolet-curable reactive composition for printing inks and coating compositions containing 10 to 23% by weight polyepoxyacrylates having a viscosity of 10 to 150 Pa.s, 30 to 50% methacrylic esters of at least trihydric alcohols having a viscosity of 0.1 to 6.5 Pa. 17 to 33% of unsaturated polyesters having a viscosity of 2.5 to 50 Pa.s, 0.02 to 0.08% of hydroehinone and di-tert-butyl-p-cresol polymerization inhibitors, 0 to 8% silicone-based reagents, 0 to 4% polyethylene wax with a softening point of up to 110 ° C, 0 to 14% ethylene glycol monoethyl ester and optionally up to 20% pigments and fillers, wherein the ratio by weight of polyepoxyacrylates: methacrylic esters: unsaturated polyesters is (0.15 to 0.25): (0.4 to 0.6): (0.22 to 0.38) and 1 to 10% of a photoinitiator from the group of benzophenone, benzoin, anthraquinone and its derivatives to 100% reactive composition added immediately to the before application and curing.

Polyepoxyacrylates are the reaction products of polyepoxides with acrylic or methacrylic acid, where per epoxy equivalent of the polyepoxides is 0.3 to 1.0 carboxylic equivalent of (meth) acrylic acid. These products are manufactured and supplied by a variety of manufacturers of semi-finished products for the paint industry under various trade names.

The (meth) acrylic esters of at least trihydric alcohols are the reaction products of the esterification of acrylic or methacrylic acid with polyalcohols having three or more hydroxyl groups.

The most prominent representatives are: trimethyloipropane triacrylate, pentaerythritri triacrylate, pentaerythritetraacrylate.

Unsaturated polyesters are the reaction products of dibasic unsaturated acids and dibasic alcohols. Commercial products are mostly based on maleic anhydride and aliphatic glycols. In some cases, they contain some reactive solvent in addition to this resin component. For the purposes of this invention, it is suitable to work with polyesters without a reactive solvent.

Additions of inhibitors such as hydroquinone, di-tert-butyl-p-cresol and others are necessary to obtain storage stability, as is generally the case with vinyl polymerizable systems.

In order to obtain defect-free surfaces of cured coatings, it is necessary in the compositions of the invention to use the addition of effective silicone-based flow agents which are products of various additive manufacturers.

These compositions, when added to the radical polymerization initiators of the invention, are useful for coating and printing various UV-curable substrates.

Known photoinitiators based on benzophenone or its derivatives such as Michler's ketones, benzoin and its derivatives, anthraquinone and its derivatives and others can be used as ultraviolet curing initiators.

The invention is illustrated by the following non-limiting examples of formulations. (Parts and% in the following examples are by weight unless otherwise indicated.)

Example 1

UV-curable blue ink:

Polyepoxyacrylate (viscosity: 132 Pa.s) ......................................... 22.3%

Pentaerythritri triacrylate (viscosity: 2.4 Pa.s) ........................... 39.0 %

Unsaturated polyester Setaroi 3616 (from Synthese, The Netherlands) (reaction product of maleic anhydride and propylene glycol) (viscosity 13.5 Pa.s) ....................... .................................... 17.7%

Cyanine Lutetia HNJ (phthalocyanine blue pigment) .............................. 16.0%

Hydroquinone ................................................. .................... 0.05%

BYK 320 (firms: Byk Malincrodt, Germany, -substituted silicone) .................... 3.00%

Ceridust 3620 (firms: Air Prod., USA, micronized polyethylene softening temperature: 90 ° C) .............................. ........................... 1.00%

Ethylene glycol monoethyl ether ................................................ ....... 0.95%

6.5 parts of Irgacure 651 photoinitiators (from Ciba-Geigy, Switzerland, -benzyldimethylketal) were introduced into 100 parts of this mixture, and after proper homogenization, the resulting product had a viscosity of 18.5 Pa.s (Laray, 25 ° C) and tack. 235/100 m.min ¹ , 30 ° C used for printing paper. The printed paper was then placed under an ultraviolet radiation source (power input 4.2 kW). The print was cured in 2.5 seconds and the cured color film showed good elasticity, high gloss and good optical density.

Example 2

UV curable varnish: _x

Polyepoxyacrylate according to example 1 ............................... 12.00%

Trimethylolpropane triacrylate (viscosity: 0,3 Pa.s) ................................ 48,80%

Unsaturated polyester according to example 1 ............ 32,40%

Hydroquinone ................................................. .... 0,07%

Baysilon 01 (companies: Bayer, Germany, -substituted silicone) ............. 0.05%

Ceridust 36 20 according to example 1 ............... 3.00%

Ethylene glycol monoethyl ether .............................. 3.68%

4.5 parts of the photoinitiators of Example 1 were introduced into 100 parts of this mixture, and after proper homogenization, the resulting viscosity of 1.67 Pa.s was used for coating the polypropylene film. The lacquer layer was cured by ultraviolet radiation within 0.8 seconds and the cured lacquer film showed good adhesion, excellent elasticity and excellent gloss level.

Example

Screen printing paste for decoration of ultraviolet-curable ceramic tiles.

Polyepoxyacrylate according to example 1 ......

Pentaerythritri triacrylate according to Example 1 Unsaturated polyester according to Example 1.

Hydroquinone ..........................

BYK 320 according to example 1 ...............

Ceridust 3620 according to example 1 .........

Ethylene glycol monoethyl ether ...........

20.50% 31.00%

31.50% 0.06 i 3.70% 0.50 i

12.74% by weight of this mixture was further mixed with 2 parts of Irgacure 651 photoinitiator according to Example 1, 4 parts of ceramic dye K 507 (mixture of oxides: steep, ferric and aluminum) and 64 parts of flux (ZTA 6473) (lead-silica glass) and perfectly homogenized. The paste thus formed was applied to a ceramic body through a sieve. This printed tile was then placed under an ultraviolet radiation source (6.4 kw power) for 1.5 seconds.

After this time, the printed layer was dry and capable of handling. The tile was then fired at 975 ° C for 50 minutes. The surface of the final decor showed a good drawing without tearing and other defects.

Claims (1)

OBJECT OF THE INVENTION 1. An ultraviolet-curable reactive composition for printing inks and coating compositions, characterized in that it consists of 10 to 23% by weight of polyepoxyacrylate having a viscosity of 10 to 150 Pa.s, 30 to 50% (meth) acrylic esters of at least trihydric alcohols having a viscosity of 0, 1 to 6.5 Pa.s, 17 to 33% unsaturated polyesters having a viscosity of 2.5 to 50 Pa.s, 0.02 to 0.08% of hydroquinone and di-tert-butyl-p-cresol polymerization inhibitors, 0 to 8% silicone-based flow agents, 0 to 4% polyethylene wax having a softening point of up to 110 ° C, 0 to 14% ethylene glycol monoethylether and optionally up to 20% pigments and fillers, wherein the ratio by weight of polyepoxyacrylate: (meth) acrylic esters : unsaturated polyesters are (0.15-0.25): (0.4-0.6): (0.22-0.38), and 1 to 10% of a photoinitiator from the group of benzophenone, benzoin, anthraquinone and derivatives thereof to 100% reactive composition added immediately prior to application and curing. Severography, n Price 2,40 Kčs