CS248057B1 - A method of producing washable wallpaper with extruded pigment and filled polyolefins - Google Patents

Abstract

Method for producing highly washable wallpapers based on the technology of extrusion coating of pigmented and filled polyolefins. Pigmented and filled polyolefin is applied, mainly low-density polyethylene with a melt flow index of 2 to 55 g/10 min, containing 3 to 45 wt. % of thermally treated inorganic pigments and fillers, such as titanium dioxide, zinc oxide, calcium carbonate, talc, kaolin or other mixtures, organic pigments, heat and light stabilizers and processing additives onto paper with a basis weight of 40 to 300 g/m2, while the surface of the filled film is subsequently treated mainly by corona discharge, printed with paints with adhesion to polyolefin surfaces and mechanically treated by embossing or perforation. The invention can be used in the entire paper industry in the production of wallpapers.

Description

248057

BACKGROUND OF THE INVENTION The present invention relates to the manufacture of washable tablets with extrusion coating of pigmented and filled polyolefins on a paper substrate.

The surface treatment of the wallpapers serves mainly to improve the utility properties, greater durability and, above all, the possibility to wash the wallpaper on the surface. These tapes can then be used for very exonerated sites with relatively high resistance.

The increased surface resistance of the wallpaper is usually ensured by surface coating of wallpaper with polymer-based lacquers, by adding synthetic fibers to paper-catching or by extrusion coating of clear polyolefins. Impregnation of tape with a urea-formaldehyde or melamine-formaldehyde resin is also a common procedure (U.S. Pat. No. 2,521,102). More often, however, varnishing systems are used, whether based on aqueous dispersions or different solvents. Treatment with surface-silicone preparations has also proven to be partially successful, thereby providing good water repellency while maintaining good gas permeability (U.S. Pat. No. 5,339,666). However, these modified wallpaper surfaces do not achieve as good washability as those with polyolefin film coating, they have greater abrasion resistance.

The good water resistance of the wallpaper, however, makes it impossible for the second layer of wallpaper to stick to the other side, as the adhesives used are mostly water-based. The removability of such modified wallpapers is practically dry, which is achieved by a special paper backing (British Patent No. 1 311 862).

A very common procedure for obtaining wallpaper and moisture resistance is the use of a mixture of cellulosic and synthetic fibers (British Patent No. 1,423,967 or 1,569,417). The porosity of these wallpapers is then obtained by embedding (U.S. Pat. No. 2,727,687, U.S. Pat. No. 2,355,949, U.S. Pat. No. 1,547,620) or needle punching (U.S. Pat. 75) The disadvantage is the relatively complicated production of the liner and poor tolerability of different types of fibers.

The good washability of wallpapers is achieved very successfully by creating a film of polymeric wallpaper. The most widespread ta-pets of this kind include wallpaper with a layer of soaked PVC, usually on a paper backing.

The main disadvantage of these wallpapers is their worse dimensional stability, health defect and flushing of the wetting agents on the surface as well as the formation of toxic and harmful substances during their burning (hydrogen chloride, phosphine, etc.). These drawbacks are solved by patents dealing with extrusion coating of polyolefins on printed paper. For example. U.S. Pat. No. 2,659,192 or by glueing various plastic films with papioma, fr. U.S. Patent No. 2,202,521, fr. U.S. Patent No. 2,322,737 to provide high washability for wallpapers. The disadvantage of these wallpapers is mainly the surface appearance, very low water vapor and gas permeability. The need for special paints resistant to high-temperature extremes. Increasing the water vapor permeability of these wallpapers addresses some patents such as fr. U. S. Patent No. 2,227,125, wherein the polymer is applied to a paper support, using a cooling roller with a special coating. Good permeability in these wallpapers can be achieved by mechanically perforating the surface of the polymer film of US Patent No. 3,706,410 and Japanese Patent No. 04,707 / 75.

SUMMARY OF THE INVENTION The object of the present invention is to provide a washable wallpaper with extrusion-deposited and filled polyolefins. Subsequent treatment of the surface of the pigmented and filled films by conventional drilling, most often by corona discharge, is suppressed by a wallpaper pattern.

For printing, paints intended for the overprinting of polyolefinic surfactants, such as nitrocellulose and polyamide dyes, may be used. Pigments and fillers in polyolefins have the task of removing the polyolefinic appearance of the wallpaper by increasing both opacity and enhancement and improving the anchoring of the color on the surface of the film, i.e. an overall improvement in the wallpaper surface suppression.

SUMMARY OF THE INVENTION The present invention relates to the production of washable wallpapers with extrusion coating of pigmented and filled polyolefins, or of mixed polygene-filled and filled concentrate concentrates, to a paper backing having a basis weight of 40 to 300 g / m @ 2, wherein the filled polyolefins containing 3 to 5% are applied. 45 weight, heat treated inorganic pigments such as titanium oxide, zinc oxide, organic pigments with high heat resistance up to 300 ° C and inorganic fillers such as calcium carbonate, talc, kaolin or mixtures thereof stabilizers and processors.

The surface of the pigmented and filled polyethylene is subsequently predominantly treated with a coranic discharge, suppressed with paints having good adhesion to the polyolefinic surfaces, and mechanically perforated to increase the water vapor permeability.

By using pigmented and filled polyolefins, an improvement in the overall size of the base for the wallpaper production is achieved, since the polyolefin surface is duller and has a more natural impression. Improved surface printability is achieved, the adhesion of the polyolefinic film to the paper substrate is improved - due to increased surface polarity due to inorganic pigments and fillers.

Depending on the type of pigment used and the filler, the barrier properties of the papermaking paper, as well as the water vapor permeability, of the steam and gases can be varied by increasing or decreasing them. For the production of extruded wallpapers according to the invention, polyethylene having a wide molecular weight distribution with a melt index of ITT of 2 to 25 g / 10 min is used, with a sITT of 7 g / 10 min being most preferred, or modified modified types. polypropylene for extrusion coating as described in Czechoslovak Patent AO No. 210 738 or in U.S. Pat. No. 992,388 or Japanese Patent No. 52,138,539. The basic problem in extrusion coating of pigmented and filled polyolefins is to reduce the thermal stability of the system as it is necessary to operate at high temperatures and long movement times of the material in the processing facility where to deep degradation! polymer, which results in the formation of gaseous fumes of degradation that occur at the melt film extrusion causes cracks and non-homogeneity.

The temperature of the melt must be high enough to ensure complete anchoring of the polymer in the paper support. This is accomplished by the appropriate composition of the stabilizing system, by the heat treatment of the pigments and fillers, and a combination of both.

The produced extrusion-embossed and filled polyolefin pads must meet the requirements for light-colored shade of the substrate. j. against sunlight and UV radiation. This can be achieved by the appropriate use of light-fast stabilizers.

The components of the stabilizing system necessary to achieve the above-mentioned light stability can be contained in the pigmented and filled polymers, in the concentrate or in the pure polymer.

Particularly suitable pigments are titanium dioxide, zinc oxide, high-temperature organic pigments and, in particular, calcium carbonate as the filler, optionally magnesium, talc, kaolin. These fillers must have an average particle size of less than 10 µm, preferably about 1 µm, with a low particle size distribution, should be hydrophobicized by known processes to provide good bonding between pigment, filler and polyolefin particles, and must not contain moisture , must not release gaseous products and must not wear wear and corrosion of the ex-nozzle nozzle.

By suitable composition of the stabilizing system, the heat treatment of the pigments and the filler, it is possible to obtain materials which can be applied to the paper backing or carton of the backing up to 400 m / min of anosos by 15 to 100 g / m 2, whereby the adhesion to the backing is without cracks and surface defects, it is transverse and steadily uniform, achieving a uniform dispersion of the pigment or filler in the polyolefin.

The paper substrate with extrudate and filled polyolefins for washable wallpaper preparation needs to be surface-treated prior to printing to enhance the surface tension of the pigmented and filled polyolefin film. Surface treatment can be done by known methods, such as flame treatment, corona discharge, chemical processes, ie by the application of oxidizing agents, the most common procedure being corona discharge, which can be done in one operation with extrusion or in one operation suppression, or separately.

The treated surface of the extruded substrate of the pigmented and filled polyolefins can be suppressed by techniques used in the suppression of paper wallpapers such as flexographic printing, gravure printing, screen printing by using paint having good adhesion to the treated polyolefinic surface treated with a cellulose or polyamide base.

The surface of the printed wallpaper with the pigmented and filled polyolefin extrusion coating can be treated by mechanical embossing as well as by perforating the polymeric film layer to increase the water vapor and gas permeability. Example 1

The 100 g / m 2 bleached kraft paper sheet was extruded at 150 m / min at a weight of 40 g / m 2 pigmented and filled with polyethylene having a melt index of 7 g / 10 min with 4 wt. % TiO 2 and 20% by weight of micronized calcium carbonate. TiO 2 and CaCO 3 were prepared at 140 ° C for granulate preparation, with 0.1 wt. % of calcium stearate.

Polyethylene was stabilized by a synergistic mixture of polyphenolic and phosphite stabilizers and also contained light stabilizers to prevent light aging.

Melt coating of this mixture was carried out on an extrusion coating machine with a screw diameter of 114.4 mm and a screw length / diameter ratio of 28: 1 at a melt temperature of 300 ° C, a slit width of 0.5 mm, and an airflow of 13 cm.

The paper substrate was corona treated prior to extrusion coating. The film melt is bonded to the paper web by the pre-liner line of the laminating unit in which the paper is pressurized to 350 kPa, then cooled by passing through a coolant roller with a greasy surface. Beyond the laminating unit, the paper surface with the extruded corona-filled and pigmented poly-ethylene treated paper

Claims (4)

248057 tensile strength which increased the film tension to 45 mN / m. The extruded paper of the pigmented and filled polyethylene was suppressed by a paper pattern on a 6-color nitrocellulose ink press, at the end of which the film was coated with needles of 0.2 mm diameter with a density of 1 hole per cm 2. The extruded, extruded and filled polyethylene wallpaper is processed on an embossing machine with a heated embossing roller at 70 ° C. Example 2 A 52 wt% blend of polyethylene was extruded on a 110 g / m 2 bleached sulphite paper web. % and 7 g / 10 min melt index with T102 pigment concentrates in an amount of 8 wt. % of the filled concentrate in an amount of 40 wt. %. The extrusion drying conditions are the same as in Example 1. The pigment concentrate contained 50% by weight of TiO2 and 50% by weight. Liquid PE index 20 g / 10 min. The filled concentrate contained 50 wt. % micronised calcium, 48 wt. % polyethylene with a melt index of 7 g / 10 min, 0.65 wt. % polyphenolic stabilizer and 0.65 wt. % phosphate stabilizer and 0.7 wt. % of a sphericalized light stabilizer. The processing of paper with extrusion coating of poly (ethylene, pigmented and filled concentrate on wallpaper) was the same as in Example 1. Example 3 For melt extrusion coating on unbleached sulphate paper, a melt flow rate of 20 g / 10 min containing 5 wt. % ZnO, 20 wt. % talc. The stabilizing system was used in the same manner as in Example 1. Melt coating was corrected under the same conditions as described in Example 1. A flexographic technique with polyamide colors was used to suppress. Moreover, the processing conditions are identical to Example 1. Example 4 For the extrusion coating, a mixture of polyolefins was used according to Art. AO 210,738. % polypropylene and 20 wt.% low density polyethylene, and ITIT was 35 g / 10 min. The mixture was stabilized with 0.20 wt. % phenolic stabilizer, 0.20 wt. % of the phosphite stabilizer and 0.4% by weight of the spherically shielded amine. The extrusion coating, suppression, perforation and embossing conditions are the same as Example 1. PREPARATION OF WASHABLE WALLPAPERS WITH EXTRA-EXTRACTION OF pigmented and filled polyolefins on a paper support applying a pigmented, filled polyolefin, predominantly polyethylene, with a melt flow index of 2 to 25 g / 10 min containing 3 to 45% by weight of heat-treated inorganic pigments and fillers such as titanium dioxide, zinc oxide, calcium carbonate , talc, kaolin or mixtures thereof, organic pigments, stabilizers for heat and light and processing additives for paper having a weight per unit area of 40 to 300 g / m 2, the surface of which is subsequently treated with a corona discharge, it is suppressed by adhering to polyolefinic surfaces and mechanically treated by embossing or perforation. Severografia, n. P., Závod 7, Most Price 2,40 Kcs