CS273149B1 - Lacquer for cellulosic materials' surface treatment - Google Patents

Abstract

This lacquer for surface treatment of cellulose materials forms, after drying and applying on printed matter, a smooth, shiny, slick and non-sticky coating that requires no calendaring, thus eliminating one technological operation. The lacquer can be applied from a dampening device or from the inking unit of a printing machine. The aesthetic and utility qualities of the improved printed matter have a qualitatively higher level in comparison to existing lacquers. When dehumidifying the lacquer, predominantly water with a small content of organic solvents is evaporated, thereby significantly improving the hygiene of the working environment and work safety. The lacquer contains a 60 to 80 % by weight aqueous dispersion with a content of 35 to 60 % by weight terpolymer composed of 15 to 25 % by weight acrylic or methacrylic acid, 30 to 50 % by weight alkyl ester of acrylic or methacrylic acid with 2 to 8 carbon atoms in the alkyl, preferably ethylacrylate and 30 to 50 % by weight vinyl monomer, preferably styrene. It further contains an 8 to 18 % by weight aqueous dispersion with a content of 35 to 60 % by weight terpolymer composed of 40 to 50 % by weight butylacrylate, 45 to 55 % by weight styrene 0.1 to 5 % by weight acrylic acid, 5 to 10 % by weight organic solvent, preferably ethanol or toluene, 1 to 4 % by weight ester wax, 1 to 4 % by weight paraffin wax, 0.5 to 3 % by weight amines, preferably ammoniac or triethanolamine, and 0.02 to 0.2 % by weight anti-foam agent, preferably α,ω-alkoxypoly(oxyethylene).

Description

Lacquer for surface treatment of cellulosic materials

(57) After drying and application to the printed matter, a coating for the treatment of cellulosic materials creates a smooth, shiny, slippery and non-stick coating that does not require calendering, thus eliminating one technological operation.

The varnish can be applied from the dampening device or from the inking unit of the printing machine. The aesthetic and utility properties of the refined printed matter are of a higher quality compared to existing varnishes. When the paint is dried, mainly water with a low content of organic solvents evaporates, which significantly improves work environment hygiene and occupational safety. The varnish contains 60 to 80% weight. % aqueous dispersions containing 35 to 60 wt. % terpolymer of 15 to 25 wt. % acrylic or methacrylic acid, 30 to 50 wt. % alkyl ester of acrylic or methacrylic acid having 2 to 0 carbon atoms in the alkyl, preferably ethyl acrylate and 30 to 50 wt. vinyl monomer, preferably styrene. It also contains 8 to 18 wt. % aqueous dispersions containing 35 to 60 wt. % terpolymer of 40 to 50 wt. % butyl acrylate, 45 to 55 wt. % styrene and 0.1 to 5 wt. % acrylic acid, 5 to 10 wt. an organic solvent, preferably ethanol or toluene, 1 to 4 wt.%, ester wax, up to 4 wt.%, paratin wax, 0.5 to 3 wt. % of amines, preferably ammonia or triethanolamine, and 0.02 to 0.2 wt. an antifoaming agent, preferably N, N-alkoxypoly (oxyethylene).

(11), (13) Bl (51) Int. Cl? C 09 D 133/00 B 41 N 3/00

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CS 273149 Bl

This invention relates to paint for surface treatment '(processing cellulosic materials, which is formulated based on a dispersion mixture of a polymer ^- and a wax in water. After coating the cellulosic · material dispersion varnish and drying, a smooth, glossy and tack-free coating. This refining printed matter is can be carried out technologically on the painting equipment or directly in the printing machine.

Varnishes for the refinement of printed materials are known which, after application and drying, form a smooth, glossy and non-sticky coating. They are based on natural resins or combinations thereof, such as copal, shellac, manila. These resins are usually dissolved in mixed organic solvents, the essential component of which is ethanol. Other types of finishing coatings include chemically modified natural polymers such as nitrocellulose or cellulose esters, especially acetylcellulose, also in a solution of mixed organic solvents, the essential component of which are alkyl esters of acetic acid.

These lacquers have a number of drawbacks in terms of technological application. Because they contain mixtures of organic solvents, it is necessary that the ink is completely dried before applying the lacquers, so that it is not attacked by organic solvents. This limits the possibility of direct application of the lacquer in the printing machine. A further drawback of these lacquers is the evaporation of organic solvents during handling and coating and the necessity of drying the coating in non-explosive dryers. Organic solvents must also be used to clean the coating equipment. Therefore, when working with these varnishes, strict hygienic and safety regulations for working with flammable materials must be strictly observed. In order to increase the gloss of the refined surface of the printed matter it is necessary in many cases to carry out an additional technological operation - calendering. A significant disadvantage of all the above-mentioned varnishes is their unsuitability for direct varnishing in printing machines.

The aforementioned drawbacks are eliminated by the lacquer for the surface treatment of cellulosic materials according to the invention, which comprises 60 to 05 wt. % aqueous dispersions containing 35 to 60 wt. % terpolymer of 15 to 25 wt. % acrylic or methacrylic acid, 30 to 50 wt. % alkyl ester of acrylic or methacrylic acid with 2 to 0 carbon atoms in alkyl, preferably ethyl acrylate and 30 to 50 wt. vinyl monomer, preferably styrene. It also contains 8 to 18 wt. aqueous dispersions containing 35-60 wt.%, terpolymer of 40-50 wt. % butyl acrylate, 45 to 55 wt. % styrene and 0.1 to 5 wt. acrylic acid. It also contains 5 to 10 wt. % organic solvent, preferably ethanol or toluene; % wax, 1 to 4 wt. paraffin wax,

0.5 to 3 wt.%, Amines, preferably ammonia or triethanolamine, and 0.02 to 0.2 wt. an antifoaming agent, preferably α, α-alkoxypoly (hexylene).

As wax solvents, alcohols, preferably ethanol and propanol, alkyl acetates, ketones, chlorinated hydrocarbons, aliphatic hydrocarbons, preferably toluene and xylene, or mixtures thereof can be used. Beeswax, Japanese wax, candelilla, preferably montan wax and carnauba wax, cetyl alcohol, stearic acid, poly (oxyethylene) with a molar mass of 6,000 to 10,000 may be used as ester saponifying waxes which significantly reduce the tackiness of the lacquer coating. low molecular weight oxidized polyethylene. From paraffinic waxes it is possible to use microwax, ceresin, preferably paraffin.

The amines which can be used are mono-, di-, triethanolamines, morpholine, preferably ammonia. Suitable antifoams are salts of sulphonated oleic acid, high molecular weight fatty alcohols, silicone emulsions, preferably t-alkoxypoly (oxyethylene).

The advantage of the lacquer is that, when applied to the printed matter and dried in the coating equipment or directly in the printing machine, it forms a smooth, glossy, slippery and non-sticky coating on its surface, which does not require calendering, thus eliminating one technological operation. When the paint is dried, most of the water evaporates with a small proportion of organic solvent, which significantly improves occupational hygiene and safety. At the same time, environmental risks are reduced. The same advantages are achieved in the maintenance and cleaning of the coating equipment, since water can be used instead of organic solvents.

CS 273149 Bl

The varnish is suitable for surface treatment of cellulosic materials such as paper, printed paper and foils to achieve a high gloss and slip surface. The varnish can be applied from a dampening device or inking machine of the printing machine, thereby reducing the handling time of the printed material and reducing the number of operators. The aesthetic and utility properties of the refined printed matter are of a higher quality compared to existing varnishes. The lacquer according to the invention replaces the previously used lacquers containing organic solvents and removes their exhalation during drying of the lacquered printed matter and cleaning of the coating device. The lacquer is essentially an aqueous dispersion of the polymer, so that it is environmentally safe and flammable safe.

The invention is illustrated by the following examples.

Example 1 68% wt. % aqueous dispersion containing 43 and ethyl acrylate and 57 wt 10% wt. % aqueous dispersions containing 51 and butyl acrylate and 49 wt 2 wt. montan wax 2 wt. paraffin 7.5 wt. ethanol 2.3 wt. ammonia in water (25% by weight) 0.2 wt. , t-alkoxypoly (oxyethylene)

% wt. % copolymer of styrene, acrylic acid (compensator A) wt. styrene-acrylic acid copolymer (component B)

The varnish of the above-mentioned composition is applied on both sides by a system of rollers 9 to 200 g / m 2 of printed cardboard sheets. After drying, a smooth, glossy and non-sticky film is formed at elevated temperature so that the sheets can be stacked.

Example 2 80 wt. component A (from example 1) B% wt. component B (from example 1) 3 wt. carnauba wax 5 wt. toluene 2 wt. paraffin 1.9 wt. triethanolamine 0.1 wt. sulfonated oleic acid

The lacquer of this composition is applied unilaterally from the printing machine dampening machine 2 onto printed sheets of printing paper weighing 70 g / m @ 2, producing a smooth glossy and non-sticky coating after drying.

Example 3 wt. 18 wt.%, Wt.

% wt. 10% wt. 0.9% by weight 0.1% by weight of component A (from Example 1) component B (from Example 1) low molecular weight oxidized polyethylene microwax propanol ammonia in water (25% by weight) .alpha.,. Beta.-alkoxypoly (exyetylene).

The varnish of the above composition is applied to the varnishing apparatus by a set of rollers on acetate foil. After drying at elevated temperature, a smooth, glossy and non-sticky film is formed.

CS 273149 Bl

SUBJECT OF THE INVENTION

Claims (1)

Paint for the treatment of cellulosic materials, characterized in that it contains 60 to B5% by weight of an aqueous dispersion containing 35 to 60% by weight of a terpolymer of 15 to 25% by weight of acrylic or methacrylic acid, 30 to 50% by weight of an acrylic or methacrylic acid alkyl ester having 2 to 8 carbon atoms in the alkyl, preferably ethyl acrylate and 30 to 50% by weight of vinyl monomer, preferably styrene, further comprising 8 to 10% by weight of an aqueous dispersion containing 35 to 60% by weight of terpolymer of 40 to 50% by weight of butyl acrylate 45 to 55 wt.% Styrene and 0.1 to 5 wt.% Acrylic acid, further comprising 5 to 10 wt.% Organic solvent, preferably ethanol or toluene, 1 to 4 wt.% Ester wax, 1 to 4 wt.% Paraffin wax, 0.5 to 3% by weight of amines, preferably ammonia or triethanolamine, and 0.02 to 0.2% by weight of an antifoam Reagents preferably *; , Λτ-alkoxypoly (oxyethylene).