CS239378B1 - Dispersedc varnish for wallpapers with matted effect - Google Patents

Abstract

The dispersion varnish is based on wallpaper polyvinyl acetate dispersion and fillers. The essence is that the lacquer consists of a polyvinyl acetate dispersion or a combination thereof with butyl acrylates, dibutyl phthalate, powder, or colloidal silica, optionally polyvinyl chloride, urea-formaldehyde resin and trivalent aluminum salts. Can be used for wallpaper editing, protection advertising and documentation material to treat walls in exposed areas areas.

Description

The invention relates to a dispersion varnish for matte-effect wallpapers.

Good varnish for lignocellulosic materials must have a high degree of washability, good adhesion to the varnished material, high elasticity and resistance to mechanical stress. In many cases, the lacquer is required to have good water vapor permeability and to exhibit a frosted effect so that it is as unnoticeable as possible to the naked eye. An important criterion is its health safety after curing, the lowest possible costs as well as easy workability in the surface treatment of the treated material.

For example, in order to obtain washable wall papers, high density polyethylene is coated by extrusion at a temperature of 310 ° C according to German Patent 2,659,192 on a base paper weighing 130 g / m ² . Printing inks must withstand temperatures up to 325 ° C. The height of the polyethylene deposit is 15 g / m ² . After extrusion, so-called "shock" cooling is required.

The disadvantage of this process lies in the high investment costs of purchasing the extruder and the necessity of using special heat-resistant inks. In order to achieve a matt effect, the extruder must be equipped with a paint roller.

Similar to the previous patent, the washability of the coating is achieved by the extrusion coating of polyethylene according to French patent 2,227,125. The disadvantage of this process is that the extrusion coating is not breathable and it is necessary to use a special cooling cylinder which perforates the extruded polyethylene film. To achieve a higher degree of permeability, additional heat treatment of the wallpaper is required.

French patents 23 22 737 and 22 02 521 are concerned with the production of washable wallpaper by laminating a film on paper. The process is even more expensive than the excretion system and its further disadvantage to the proposed patent is the application of laminating solvent adhesives, which requires specially adapted manufacturing spaces and the incorporation of solvent regenerators.

The production of embossed washable wallpaper according to U.S. Pat.

Heating to 160 ° C is necessary to melt the polyethylene and then emboss at this temperature. The method requires polyethylene and polypropylene with a fiber length of 2.5 mm and a diameter of 1 mm.

The above-mentioned drawbacks are overcome by the lacquer according to the invention, which consists of 56 to 84 wt. % of a polyvinyl acetate dispersion, or a combination thereof with butyl acrylates, 0.4 to 4 wt.%, preferably 2 wt. dibutyl phthalate, 1 to 10 washes. wt. % of colloidal or powdered silica, preferably 5 wt. % colloidal silica and optionally up to 12 wt.%, preferably 5 wt. % polyvinyl chloride, optionally up to 9 wt.%, preferably 5 wt. % of urea-formaldehyde resin and optionally up to 5 wt.%, preferably 1 wt. trivalent aluminum salts.

Example 1

0.5 parts of dibutyl phthalate, 10 parts of emulsion polyvinyl chloride, 4 parts of industrial water-soluble aluminum sulphate are added successively to 84 parts by weight (hereinafter part of the homopolymer dispersion of polyvinyl acetate) with slow stirring. 0.5 HD of urea-formaldehyde resin diluted 1: 3 with industrial water is added with slow stirring, and the mixture is allowed to react without stirring for 6-8 hours. After this time, 1 HD of silica powder is gradually added under slow stirring so that the dispersion system did not break.

The viscosity of the mixture is adjusted by further addition of industrial water so that the discharge time measured by the discharge cup No. 4 according to ČSN 67 3031 is 14 seconds. The prepared varnish can be applied immediately, for example, on the varnishing of wallpaper with an air wiper. The basis weight of the application of the wallpaper varnish applied to dry stamping should be 7 g / m ² .

Example 2

To 56.7 parts by weight (hereinafter d.) Of the homopolymer polyvinyl acetate dispersion is slowly added, with slow stirring, 1.8 d. Dibutyl phthalate, 25 h. D. Copolymer acetate acrylic dispersion, 1 h. D. The mixture thus prepared is diluted with industrial water for 4 h. The urea-formaldehyde resin diluted 1: 3 with industrial water was added to the mixture with slow stirring for 7 h. The mixture is allowed to react without stirring for 6-8 h. After this time, 8 h. D. Of colloidal silicon dioxide are gradually added under slow stirring to avoid breakdown of the dispersion system. Proceed as in Example 1.

Example 3

0.4 parts by weight of dibutyl phthalate and 24.6 parts by weight of copolynier acetate-acrylic dispersion are gradually added to 56 parts by weight (hereinafter referred to as d.) Of the homopolymer polyvinyl acetate dispersion, with slow stirring. The mixture thus prepared is diluted with industrial water for 4 h. To the mixture is added slowly 939378 µl of 9 h. D. Urea-formaldehyde resin diluted 1: 3 with industrial water. The mixture is allowed to react without stirring for 6-8 h. After this time, 10 h. D. Of colloidal silicon dioxide are gradually added under slow stirring in order not to break the dispersion system. Proceed as in Example 1.

Example 4

4 h. D. Dibutyl phthalate, 12 h. D. Polyvinyl chloride, 5 h. D. Aluminum sulphate, dissolved in industrial water, are gradually added to the 74 h. P. Homopolymer dispersion of polyvinyl acetate, with slow stirring. The mixture thus prepared is diluted with industrial water for 4 h. The mixture is allowed to react without stirring for 6-8 hours. After this time, a slow addition of 1 h. D. Of silica powder is gradually added with slow stirring to avoid the dispersion system being broken. Proceed as in Example 1.

The lacquer according to the invention can be used for treating wallpaper, protecting advertising and documentary material from contamination in the exhibition area by spraying with a spray gun. Another application is the surface treatment of walls in exposed areas such as kitchens, corridors, toilets, etc.

Claims (1)

A matt-effect wallpaper dispersion varnish based on a polyvinyl acetate dispersion and fillers, characterized in that it consists of 56 to 84% by weight. % of a polyvinyl acetate dispersion, or a combination thereof with butyl acrylates, 0.4 to 4 wt.%, preferably 2 wt. % dibutyl phthalate, 1 to 10 wt. % colloidal, or powdered, cristoyne oxide, preferably 5 wt. % colloidal silica and optionally up to 12 wt.%, preferably 5 wt. % polyvinyl chloride, optionally up to 9% by weight, preferably 5 washes. wt. % of urea-formaldehyde resin and optionally up to 5 wt.%, preferably 1 wt. trivalent aluminum salts.