GB2045111A - Wallcoverings - Google Patents

Abstract

A wallcovering comprising a base to the surface of which granules or powder are fused to present a relief or textured effect. The base may be on a paper substrate. The base and granules or powder may be derived from a common foamable plastisol, the base, prior to foaming, being in the liquid viscous phase and the powder or granules being in the solid phase, with fusing and foaming taking place at a common source of heat. Contrasting pigmentation may exist between the base and the granules or powder. Embossing may be employed with foamed granules or powder to give a valley inking effect.

Description

SPECIFICATION Wallcoverings This invention relates to wallcoverings presenting a relief or textured effect. The term "wallcoverings" is intended to include ceiling coverings.

The invention provides such wallcoverings of enhanced durability and generaily of pronounced relief effect with scope for using a wide range of colours and decorative finishes.

The wallcovering of the present invention comprises a base to the surface of which granules or powder of plastics material are fused.

The base may be laid on or united with a substrate such as a paper or non-woven web.

The base and/or the granules or powder may be in a foamed or partly foamed state.

In one form of the invention the base is a cured plastisol, foamed orunfoamed, and the granules or powder are formed from, preferably, the same plastisol and foamed.

The substrate may be pre-embossed.

The base may be applied overall to a substrate or in areas.

The wall covering may be embossed in areas by crushing the relief effect in those areas.

The invention provides a method of making a wallcovering having a relief effect comprising the steps of putting down a base plastics material and fusing granules or powder of plastics material predominantly to the surface of said base to presentthe relief effect.

Where either the base plastics material or the granular or powdered plastics material contains a blowing agent to allow heat foaming then the fusing and the foaming can be arranged to take place together at one source of heat.

In a preferred method making a wallcovering in accordance with the invention the base is derived from a plastisol composition, with or without a blowing agent, in the liquid viscous phase and the granules or powder are formed from the same plastisol composition, including a blowing agent, and in the solid phase, curing and foaming being carried out in the same heat source.

The granules or powder may contain colouring pigments, or have special coatings, such as metallic coatings or contain glitter materials.

The granules or powders may be selected to have a limited or extensive size range. Pigmenting could be varied according to size of granules or powder or various pigments could be used at random with various granule or powder sizes.

For the granules or powder a clear foamable plastisol can be used which goes opaque when it foams but can be clarified by compressing such as with embossing rolls. By suitable selection of base colour and ganule or powder colours a valley printing effect can be achieved with very sharp delineation between valleys and peaks and with perfect colour registration.

A printed vinyl coated paper may provide a base and substrate respectively and to this can be fused all over clear granules or powder to give a textured protection top coating.

A printed vinyl coated paper may again provide a base and substrate and to this is fused random foamed granules of varying sizes coloured to contain a colour present in the printed vinyl coat.

The invention will now be described further with reference to the accompanying drawings in which: Figure lisa process diagram illustrating the invention; Figures 2,3 and 4 are cross-sectional views of wallcoverings according to the invention; and Figures 5 and 6 are views of the surfaces of wallcoverings according to the invention.

In Figure 1 a stock tank 10 containing a plastisol and blowing agent in the liquid phase has two outlets 11, 12. Outlet 11 supplies a coater 13 and outlet 12 leads to gelling apparatus 14 (such as a hot drum or a release belt) to convert the liquid phase plastisol into a gel which, at a station 15, hardens on cooling. Immediately on leaving the gell apparatus the gel may be cut, such as into strip form, so as to accommodate it to a granulator 16 after it has cooled. From the granulator 16 the material is blended, such as with a flowing aid, secondary colours or decorative additives, in a blender 17.

In one typical way of forming the wallcovering, 90 gm --2 paper 20 from a stock roll 21 is caused to pass to the coater 13 where it receives a base coating 22 of plastisol and then the coated paper is caused to pass below a metered outlet 17a of the blender 17 where it receives a coating 23 of blended plastisol in the solid, powdered or granular, phase. The solid phase blended plastisol adheres to coating 22 but due to the characteristics of the two coatings the solid phase remains prominently on the surface of the coating 22.

Excess power or granules in the coating 23 is removed at a blower station 24 and recovered in an extractor.

The paper 20 together with its two coatings then passes to a storage roll 26 via a station 25. At station 25 the powder or granules in coating 23 fuse to the surface of coating 22 to form a very strong bond.

The paper 20 may be a plain or pre-embossed paper and may be given print-coated areas at the coater 13 so that patterning is generated. Material other than paper could be used to support the plastisol base coating 22 such as non-woven materials and other web or film materials. Other variants are described below in Example 1 to 13. Line 30 is an alternative or modifying stock line for coating 22.

In Figure 2 there is shown, in section, the backing paper 20 and the coating 22 and 23.

Figure 3 is distinguished over Figure 2 in that the coating 22a is unblown.

Figure 4 is distinguished over Figure 2 in that the coatings 22b and 23 have passed through an embossing nip. The coating 23 has been given, in the nip, a levelled surface 27 and the valleys 28 of the emboss have substantially destroyed the foam. The surface of coating 23 does not have to be levelled. It can be left untouched by the embossing operation.

Thirteen examples of wallcovering according to the invention will now be given. The examples have been correspondingly identified in Figures 5 and 6 as "Example 1" to "Example 13".

Example 1 Plastisol of the following formulation is blade coated at a weight of 90 gm-2 onto 90 g m wallpaper substrate.

Parts by Weight PVC homopolymer 100 DIDP 63 Epoxy stabiliser 3 Azodicarbonamide 4 Ti02 21 CaC03 21 Cd/Zn kickeristabiliser 2.5 Viscosity depressant 2.5 Optical brightening agent 0.05 Granules are made from the same plastisoi in the random size range of 1200 to 150 microns and these are sprinkled randomly onto the wet plastisol base at an overall coat weight of 120 gm-2 and then cured and foamed in an oven at 200"C for 60 seconds. The foamed and cured granules fuse to the foamed and cured plastisol layer.

A white randomly textured wallcovering is produced with a relief of 1.4 mm.

Example 2 Plastisol of the following formulation is blade coated at a weight of 90 gum~2 onto 90 gum~2 wallpaper base.

Parts by Weight PVC homopolymer 100 DCP 60 Epoxy stabiliser 3 Azodicarbonamide 5.5 TiO2 21 CaCO3filler 21 Zn kicker/stabiliser 4 Viscosity depressant 2.5 Granules are made from this same plastisol and mixed in roughly equal propotions with granules made from the same plastisol tinted with a small amount of yellow oxide pigment. The granules (particle size as in Example 1) are randomly sprinkled onto the wet plastisol at a coat weight of 110 gm-2 and blown in an oven at 200"C for 60 seconds to give a two tone texture effect with relief of 1.65 mm.

Example 3 Plastisol of the formulation as in Example 2 is screen printed in a design 30 onto 90 gm-2 wallpaper base 31 and granules as in Example 2 are sprinkled onto the wet plastisol. Granules not falling onto printed areas are blown off and the remainder expanded in an oven at 200cm for 60 secs. to give printed design with two tone textured surface and a relief of 2.5 mm.

Example 4 A coloured plastisol of the following formulation is screen printed onto white vinyl coated paper 40 in a brickwork design 41.

PVC homopolymer 100 DCP 65 Epoxy stabiliser 3 Azodicarbonarnide 4 Ti02 7 CaC03 filler 35 Cd/Zn kicker/stabiliser 2.5 Viscosity depressant 2.5 Coloured pigment dispersions Various A mixture of different coloured granules of particle size 800 to 150 micron is made from three differently coloured plastisols of this same basic formulation in shades of orange/brown.

When sprinkled onto the wet plastisol and expanded as in Example 3 a simulated brick effect with a textured surface is produced.

ExampleS A plastisol of the following formulation is blade coated at a coat weight of 125 gm-2 onto 90 gm-2 wallpaper base.

PVC homopolymer 100 DCP 65 Epoxy stabiliser 3 Azodicarbonamide 4 Ti02 21 CaC03 filler 21 Zn stabiliser/kicker 2.5 Viscosity depressant 2.5 Granules of particle size 630 to 300 microns made from the same plastisol are sprinkled in an overall coating of 90 gm-2 onto the wet plastisol.

The whole coating is heated in an oven at 205"C for 60 secs. to cause the plastisol and granules to expand and then embossed while still hot with a deeply engraved roller such that the resulting raised areas 50 of the design are untouched by the roller and remain with a rough texture while the compressed areas 51 take the design of the roller.

Example 6 A non-foamable plastisol of the following formulation is blade coated onto 90 gm-2 wallpaper base at a coat weight of 50 gm-2.

PVC homopolymer 100 DCP 47 Epoxyltin stabiliser 3.5 Ti02 18 CaC03filler 18 Granules of particle size 800 to 300 micron of the formulation used in Example 5 are sprinkled in an overall coating of 75 g m and heated in an oven at 200cm for 60 secs. This cures the plastisol and expands the granules.

Example 7 The non-foamable plastisol used in Example 6 is coated onto a wallpaper base but this time, granules of particle size 1200 to 200 micron made from the same non-foamable plastisol were sprinkled on as an overall coat of 100 gum 2 and then fused in an oven at 200on for 30 secs. to give a sharply textured low relief product.

Example8 Granules made from the formulation used in Example 5 of particle size 800 to 300 micron are mixed with 5% by weight of a very fine aluminium powder so that they become coated with the powder.

The coated granules are then sprinkled onto a 90 gm-2 coating of wet plastisol as used in Example 5 in an overall coating of 105 gm -2 On heating at 200"C for 60 secs. both plastisol and granules expand to give an all over metallic textured effect.

Example 9 Example 8 is repeated but using brown granules, 800 to 150 micron, from Example 4 with 10% of bronze powder and the resulting foamed product embossed while still hot with the roller used in Example 5.

Example 10 A dark blue foamable plastisol of formulation "A" below is blade coated at a weight of 105 gm-2 onto 90 gm-2 wallpaper base and then foamable granules of particle size approximately 800 microns made from a clear plastisol of formulation "B" below are sprinkled in an overall coating of 200 gm-2 onto the wet plastisol. The coating is expanded at 205"C for 60 secs. and then embossed while still hot with the roller used in Examples. Foamed granules 100 compressed by the roller become translucent showing the darker base colour through while unembossed granules 101 remain opaque. An effect similar to two tone valley inking is thus produced.

A B PVC homopolymer 100 100 DCP 65 65 Epoxy stabiliser 3 3 Azodicarbonamide 4 4 Ti02 7 CACO3 filler 35 Viscosity depressant 2.5 2.5 Zn kicker/stabiliser 2.5 2.5 Pigment dispersion 8.5 Example ii A three colour mixture of granules based on a plastisol formulation as in Example 4 of particle size 800 to 300 microns is prepared and 5% by weight of "glitter dust" of particle size 1500 and 400 microns is mixed with it. The mixture is then sprinkled at a coat weight of 112 gm -2 onto a 120 gm-2 coating of wet coloured plastisol on 90 gm-2 wallpaper base and heated in an oven at 205"C for 60 secs.

A multi-coloured textured product with bright reflecting highlights is produced.

Example 12 A sample of gravure printed vinyl coated paper is blade coated with a thin layer of di-octyl sebacate plasticiser and then sprinkled with an all over coating of non-foamable granules produced from the following clear plastisol and having a particle size of 300 to 150 microns.

PVC homopolymer 100 DOS 35 Epoxy/tin stabiliser 3.5 Viscosity depressant 2.5 The coated vinyl paper is then heated in an oven at 200"C for 30 secs. to produce a printed wallcovering having a transparent but textured protective top coating.

Example 13 A sample of gravure printed 130 foamable vinyl coated wallpaper is blade coated with a clear plastisol of the following formulation at a coat weight of 50 gm -2 and then granules 131 as used in Example 2 are sprinkled in a light overall covering at a weight of 45 gm -2 onto the wet coating.

PVC homopolymer 100 DCP 35 Epoxy tin stabiliser 3.5 Viscosity depressant 2.5 Silica matting agent 10 White spirit 15 The coated material is then heated in an oven at 200'C for 60 secs.

The small print design and colouring is such that it blends in with the colouring in the foamed granules to give a three-dimensional printed texture effect.

Claims (15)

1. A wallcovering comprising a base to the surface of which granules or powder of plastics material are fused to present a relief or textured effect.

2. A wallcovering as claimed in claim 1 in which the base is laid on or united with a substrate.

3. A wallcovering as claimed in claim 1 and 2 in which the base is foamed.

4. A wallcovering as claimed on any preceding claim in which the granules or powder are foamed.

5. A wallcovering as claimed in any preceding claim in which the base is a cured plastisol composition and the granules or powder are formed of the same composition.

6. A wallcovering as claimed in claim 2 in which the substrate is embossed.

7. Awallcovering as claimed in claim 2 in which the base is laid on or united with the substrate in a pattern.

8. A wallcovering as claimed in any preceding claim in which the relief effect has been crushed in some areas to present an embossed effect.

9. A wallcovering substantially as hereinbefore described with reference to any one of the Examples.

10. A method of making a wallcovering comprising the steps of putting down a base plastics material and fusing granules or powder of plastics material predominantly to the surface of said base to present a relief effect.

11. A method according to claim 10 in which either the composition of the base or the composition of the granules or powder, or both, contain a foaming agent and the fusing and foaming are caused to take place together at one source of heat.

12. A method according to claim 11 in which the composition for the base and the composition for the granules or powder are derived from a common source, the composition for the base being put down in the liquid viscous phase and the composition for the granules or powder being put down in the solid phase.

13. A method according to any preceding claim in which the granules or powder are pigmented to contrast with the base.

14. A method according to claim 10 in which the base is coloured and the powder or granules are formed from a clear foamable plastisol which goes opaque on foaming but clears on compression, the method being characterised in that after foaming the wallcovering is embossed.

15. A method according to claim 10 in which a printed vinyl coated paper has fused to it random granules or various sizes coloured to contain a colour present in the printing of the vinyl coat.