GB2289021A

GB2289021A - Coating a distressed glass surface

Info

Publication number: GB2289021A
Application number: GB9508805A
Authority: GB
Inventors: Colin Leslie Ellis
Original assignee: SELECTA INTERNATIONAL Ltd
Current assignee: SELECTA INTERNATIONAL Ltd
Priority date: 1994-05-05
Filing date: 1995-05-01
Publication date: 1995-11-08
Also published as: GB9508805D0; GB9408932D0

Abstract

A distressed glass surface having pitting is treated with a coating that occupies said pitting. The coating may be transparent, or it may be opaque and comprise a paint or a metal foil, e.g. gold. The glass surface may be the silvered side of a mirror, the distressing removing the silvering therefrom. The distressing may be effected by sand or shot blasting or by chemical means such as a silk-screening printing process. The distressing may be confined to selected areas of the glass surface by use of a mask 10 in the form of a stencil or in the form of a sand-blast resist printed onto the glass surface. <IMAGE>

Description

TREATING GLASS This invention relates to treating glass.

The invention comprises a method for treating a distressed glass surface having pitting caused by a distressing process, said method comprising the application to the surface of a coating that occupies said pitting.

The coating may be transparent.

The coating may be opaque.

The coating may comprise a metal foil.

Said distressing may be effected by sand or shot blasting.

The distressing may be effected chemically.

The distressing may be confined to selected areas of the glass surface by use of a mask.

The glass surface may be the silvered side of a mirror, the distressing removing the silvering therefrom.

A method for treating distressed glass in accordance with the invention will now be described with reference to the accompanying drawings, in which: Figure 1 is a front view of a mask; Figure 2 is a view of the mask adhered to the silvered side of a mirror; Figure 3 is a cross-section through the mirror during sandblasting; Figure 4 is a cross-section through the mirror during silk screening; Figure 5 is a microscopic view of the pitted glass surface; and Figure 6 is a cross-section through a framed mirror.

Figure 1 shows a plastic mask 10 which has had an animal figure 12 cut out therefrom, e.g. by a knife on a computer controlled plotter.

As illustrated, the design is simple and much more complicated designs will be used in practice. The illustration shows however that the mask can be removed in one piece from the figure 12 after the latter has been cut around by the knife. As shown in Figure 2 mask 10 is applied to the back or silvered surface ofthe mirror in one piece.

The terms silvered and silvering do not necessarily imply that the reflective coating of the mirror is entirely or indeed at all composed of silver. The reflective coating may comprise several layers of different metals or alloys, although the layer against the glass surface will usually comprise silver or aluminium.

As shown in Figure 3 a sandblaster 30 removes silvering 32 which is unprotected by the mask 10 from the glass 31. The mask is removed when the sandblasting is completed.

Alternatively as shown in Figure 4 selective removal of silvering is effected by a chemical etching process, wherein the active chemical agent is present in a paste, the paste being administered to the mirror by silk screening. In such a process a screen 40, from which wax has been selectively removed in a desired pattern, is placed over the silvered back of the mirror and the paste squeezed through by a roller 42 or squeegee in the usual way, care, however, being taken on account ofthe corrosive nature of the paste. A suitable active agent is ferric chloride used in appropriate dilution and incorporated in, for example, a cellulose based paste. However, a sandblast resist may also be silkscreen printed on to the mirror back.

Either method for removal of silvering inevitably results in distressing of the glass surface 50, Figure 5, which is manifest in pitting of said surface. The distressed surface 50 is, according to the invention, coated with a coating 52.

The coating 52 may be opaque and comprise a paint or a metal, for example, gold, foil.

The coating 52 may be a sprayed cellulose 52 which occupies the pitting, producing a smooth and transparent glass-cellulose composite. The cellulose lacquer also has the effect of protecting the silvering 32, and particularly the edges which are prone to damage and attack by atmospheric pollutants. Any clear coating which can be applied so as to fill the pitting and which has a refractive index reasonably close so that of the glass can be used in place of cellulose.

The effect of such coating is to restore a measure of transparency to the distressed area. Without such coating, the distressed area appears white, dull and unattractive.

With such coating, the mirror can be placed against a backing 62, Figure 6, which can have any desired appearance, pattern, design, colour or texture. A mottled or marbled surface might be thought suitable as a backing for a design or pattern in the silvering and such a surface will give a pleasing suggestion of depth.

Particularly if the distressing is effected by shot or sand blasting away a silvering layer, there is some effect on the edges of the remaining silvering that gives rise to a speckle or sparkle that tends to highlight the edges: this effect will also be preserved by the application of the lacquer.

It will be appreciated that it is not intended to limit the invention to the above example only, many variations being possible, such as might readily occur to one skilled in the art, without departing from the scope thereof as defined by the appended claims.

Claims

1. A method for treating a distressed glass surface having pitting caused by a distressing process, said method comprising the application to the surface of a coating that occupies said pitting.

2. A method according to Claim 1 wherein the coating is transparent.

3. A method according to Claim 1 wherein the coating may be opaque.

4. A method according to Claim 3 wherein the coating comprises a metal foil.

5. A method according to any one of Claims 1-4 wherein the distressing is effected by sand or shot blasting.

6. A method according to any one of Claims 1-4 wheein the distressing is effected chemically.

7. A method according to Claim 5 wherein the distressing is confined to selected areas of the glass surface by use of a mask.

8. A method according to Claim 7 wherein the mask is in the form of a stencil.

9. A method according to Claim 7 wherein the mask comprises a sandblast resist printed onto the glass surface.

10. A method according to Claim 6 wherein the chemical is applied by a silk-screen printing process.

11. A method according to any preceding Claim wherein the glass surface is the silvered side of a mirror, the distressing removing the silvering therefrom.