SE531452C2 - Glass wall covering - Google Patents

Description

25 30 35 531 452 but is not without inconveniences.

Thus, the patent US 6,015,622 recommends the use of a rather special laying process, which in particular comprises stirring the mill with an aqueous dispersion of a polyacrylic acid derivative. Patent DE 100 34 981, for its part, also claims a glass plate which is already provided with a cement of a special composition, obtained by means of an aqueous dispersion of a resin of the styrene-butadiene type. Patent application EP-A-722 027 also discloses the use of a specific use, comprising 50% of an additive consisting of a dilute aqueous dispersion of a synthetic resin. In these three cases, the use of a special composition mortar is indispensable and the use of the mortars commonly used by the ceramic tilers gives unsatisfactory results.

It also seems that the smooth surface of the glass is to the detriment of a good attachment of glass plates to walls of masonry. Thus, from 1925 the patent FR 599 239 advocated coating the plates with a layer of paste or varnish, derived from synthetic resins, to which fragments of glass, metal, sand, gravel are attached. marble or any other inert material. However, this method necessitates the use of ground fragments, which thus come from a costly process.

Also known from the prior art are glass wall coverings, on which a lacquer layer with a decorative function is applied to the contact surface with the wall to be clad. But the type of varnish used is likewise incompatible with the glue cement, and such proc odors should be applied to the walls by other means, e.g. using adhesive halts.

The present invention aims to remedy the above-mentioned disadvantages by proposing a wall cladding based on glass, in particular in the form of tiles, intended to cover the walls of a dwelling, which is suitable for being applied to said walls' by traditionally used methods for applying ceramic tiles, in particular through the use of ordinary adhesives.

The inventors have discovered that the main physicochemical property in this case is the permeability of the varnish to water. When this quantity is unadjusted (in this case too high taking into account the glue used) the stirring water, which has been made basically by the hydration reaction of the cement, diffuses through the lacquer layer and reacts chemically with the surface of the glass, thus making all adhesion (especially glass lacquer adhesion impossible) ), at the same time as the appearance of the glass cladding deteriorates. In its broadest sense, the coating according to the invention thus comprises a glass substrate, which on the abutment side is coated with a layer based on lacquer, characterized in that said lacquer has a water permeability which is such that said coating can be applied against the walls with the help of ordinary glue or glue cement.

The maximum permeability value of the varnish, in order for a permanent gluing to be carried out, obviously depends on the type of adhesive used.

The coating lacquer according to the invention has a water permeability at 25 ° C, expressed in cm3.cm.cm'2.s'1.Pa'1, which is preferably lower than 106, even lower than 5.107, and in particular lower than 10 '. To ensure a perfect adhesion and a mechanical durability, in particular a shear strength, with a long service life, it is even preferable that the lacquer has a water permeability at 25 ° C which is lower than 108, even 109, and even 10 "" cm3. cm.cm'2.s '". Pa'".

Since the coatings according to the invention are in some cases intended to be applied in places whose surroundings are damp (eg in bathrooms), it is even preferable that the water permeability of the lacquer covering a covering surface according to the invention is lower than 1041, even 10 "" And even 10 "" cm3.cm.cm'2.s "1.Pa '".

Water permeability is defined as the product of the amount of water vapor diffusing through a material (in cm3) through the material thickness (in cm) relative to the product of the exposed surface (in cm2) through the exposure time (in seconds) and through the pressure difference (in pascals) between the two sides of the material . It can e.g. measured by measuring the mass uptake of a lacquer film after exposure in a climate furnace, the degree of humidity of which is controlled.

This greatness depends. in the case of a polymer, primarily on the chemical nature of the polymer, then on its morphology, such as e.g. depends on the degree of crosslinking (via, for example, the content of crosslinking agent and / or the crosslinking temperature), on the degree of crystallization, on a possible alignment of the molecules. It also depends, if applicable, on the nature and amount of mineral fillers.

The coating lacquer according to the invention thus preferably comprises as binder a synthetic resin, preferably in liquid form before application, and adapted for drying in an oven. It has been observed that the paints comprising binders dried at high temperature (above 50 ° C, even up to 100 ° C) quite generally showed a lower permeability than the binders dried in air at ambient temperature, probably due to crosslinking reactions, e.g. ex. with polycondensation, which is more streamlined and gives rise to three-dimensional networks of higher density.

The binder is advantageously a polyurethane resin, prepared by crosslinking, with an isocyarlate or a polyisocyanate, of hydroxylated resins, in particular polyester resins or polyether resins, or preferably acrylic resins (or polyacrylates), which exhibit a resistance to high ultraviolet 452 4 radiation values. In this case, the hydroxylated acrylic resin preferably comes from polymerization of an acrylic styrene, while the isocyanate (polyisocyanate) advantageously does not comprise any aromatic type group. This particular combination makes it possible to obtain, in particular, low permeabilities. good heel strength properties (eg expressed as scratch resistance), and a high resistance to ultraviolet radiation.

The binder for the coating lacquer according to the invention may also contain or be based on alkyd resin (s), prepared by chemical reaction between at least one polyol, at least one polyacid and at least one fatty acid or an oil. These alkyds are generally short in oil, i.e. the weight content of oil or fatty acid in the resin is preferably lower or equal to 40%. The polyols can e.g. be composed of glycerol or pentaerythritol. The polyacids may be based on phthalic anhydride.

The oils can be sickening (such as linseed oil, wood oil or china oil). semi-sickening agents (such as soybean oil, tall oil, safflower oil or dehydrated castor oil) or non-sickening agents (such as copra oil or castor oil). To improve their resistance to water, the alkyd binders can also be modified with monomers such as styrene, vinyltoluene or acrylates, or with phenolic resins or epoxy resins. Aminoplast alkyd resins which crosslink under the action of heat are particularly advantageous binders for the coating lacquer according to the invention. The crosslinking aminopiast is preferably a ureaformol resin or melamineformol resin which provides good water resistance, especially when applied in an amount of 20 to 30% by mass relative to the dry alkyd binder.

The varnish may also comprise a binder based on thermosetting acrylic resin, e.g. prepared by crosslinking a carboxylated acrylic resin with an epoxy resin, formophenol resin or melamine formol resin, of an acrylic resin having a carboxamide function with an epoxy or alkyd binder, or also of an acrylic resin having an epoxy function with acids or polyamines.

The coating according to the invention is advantageously provided with a layer of adhesion promoter (also called "adhesion primer"), located between the glass and the lacquer, and whose function is to improve the adhesion between the glass and the lacquer. This layer is advantageously based on silanes, which makes it possible to avoid the risk of loosening due to moisture. Agents for promoting adhesion to glass, such as silanes, may also be dispersed in the varnish.

The lacquer advantageously comprises pigments, mineral and / or organic, preferably mineral, in order to give the desired aesthetic properties. These pigments are preferably of the type which is resistant to ultraviolet radiation and to moisture. Among the pigments used within the scope of the present invention are e.g. titanium oxide or zirconia, optionally doped with ions of transition elements, or also mixed oxides of the zirconium type (ZrSiO 4). The pigments are preferably free of heavy metals such as cadmium or lead.

The varnish may also contain mineral fillers, intended to optimize its physico-chemical parameters, e.g. its viscosity. The total content of minerals (pigments and fillers) in the lacquer is preferably, expressed in mass percent, comprised between 40 and 70%, even between 50 and 60%.

The coating varnish according to the invention can be applied by any type of method known to the person skilled in the art, such as curtain, compressed air spraying, screen printing or roll-coating. The screen printing method has the advantage of being able to coat only a part of the substrate. The roll-coating process consists in passing the substrate to be coated between two rolls, one of which (generally the upper roll) is coated with lacquer. For cost reasons, the method used is preferably the curtain, where a lacquer flow is created on a line which is substantially perpendicular to the transport direction of the glass substrate, which thus makes it possible to coat the entire surface of said substrate. The lacquer flow and the transport speed of the substrate are controlled so as to obtain a coating of the desired thickness, preferably 100 - 200 μm in a moist state. The lacquered substrate is then subjected to a heat treatment which makes it possible to cure the lacquer, more specifically to remove the solvent and carry out the polymerization and / or crosslinking reactions of the lacquers used as binders. The temperature used is preferably comprised between 50 and 250 ° C, in particular between 100 and 200 ° C, in order to impart to the varnish a degree of crosslinking which is suitable for reducing its permeability to water. The thickness of the lacquer layer after curing is preferably comprised between 20 and 100 μm, in particular between 40 and 70 μm, in order to obtain the desired opacity.

The glass substrate used can be of any type of flat glass (possibly bombarded with bombing procedures known to the person skilled in the art, when it comes to covering curved surfaces). These can be monolithic glasses, i.e. consisting of a single glass sheet, which can be manufactured by the at oat glass process, which makes it possible to obtain a perfectly flat and smooth sheet, or by drawing or rolling processes. In the latter case, and when the rolling rollers show former relief, the glass sheet can be printed and have motifs (eg as described in the patent document EP 493 202) on at least one of the sides, preferably the base side of the lacquer (or the back).

The glass can be clear or have different color tones, such as blue, bronze, green, gray or even pink. The light transmission of the glass can be selected between 10 and 92% for a thickness of 4 mm. A particularly preferred embodiment, in cases where the lacquer is white or ivory colored, consists in using as an glass substrate an extra clear glass sheet, ie whose iron oxide content is below 250 ppm, preferably below or equal to 200 ppm, even 150 ppm, and whose light transmission under illuminant D65 is above 89%, in particular 90%, for a thickness of 4 mm. It has been found that the optical properties of such a glass made it possible to obtain an excellent reproduction of the white or ivory color of the lacquer, while the residual green color of ordinary clear glass, the iron oxide content of which is of the order of 1000 ppm, is particularly obvious.

The thickness of the glass substrate is preferably comprised between 2 and 19 mm, preferably between 4 and 10 mm, in particular between 5 and 9 mm.

This glass sheet can be made matt on at least one of the sides (preferably the front) by various matting methods, e.g. matting with hydrofluoric acid or sandblasting. This matting can be done on the whole side or on special zones, to create matte motifs that are slightly deepened. This latter embodiment can be carried out while protecting the zones which are not to be etched with an acid-resistant coating, which is then removed. The matte appearance can also be obtained by applying an organic or mineral enamel.

A reflective layer, preferably a silver layer prepared by silvering methods known to the person skilled in the art, can also be placed between the glass substrate (optionally provided with adhesion promoters of the silane type) and the lacquer, the latter fulfilling the function of lacquer which protects the silver layer against corrosion.

A decoration in one or more colors, produced by serigraphy methods or ink jet, is advantageously placed between the glass substrate (possibly provided with adhesion promoters of the silane type) and the varnish, and / or on the front. lvlan can e.g. combine the application of decors on the front and on the back.

A particularly interesting embodiment relates to a wall cladding according to the invention, i.e. coated with a lacquer on the back, said back side then being cut by mechanical means (in particular by grinding by means of grinding wheels with more or less intricate profiles) to create e.g. lines 1 - 30 mm wide and 0.5 - 3 mm deep, where all the varnish has thus been removed. A decorative layer, preferably a silver layer made by classical silvering methods, can then be applied to the back. In the case where the incisions are made along straight lines at regular distances and in two rectangular directions, one can thus, starting from a single glass panel, applied to the visible printing side, obtain a plurality of plates separated by joints, while obtaining the advantage with a front side which forms a smooth surface, which avoids the problem of soiling of the joints and considerably facilitates the cleaning. This embodiment of the invention also makes it possible to reduce the time for laying the glass plates by saving the joining steps.

The glass substrate can also be coated with functional layers such as stacks of anti-reflective layers, layers with self-cleaning functionality (eg containing titanium oxide, preferably crystallized in the form of anatase and / or rutile, which likewise exhibit the properties of anti-dirt, anti-bacterial, anti-fog and anti-condensation) or hydrophobic layers. Layers that provide anti-slip properties, especially in the form of enamel, are especially appreciated in the case of floor coverings.

Anti-wear or anti-scratch layers can also be applied to the substrate according to the invention.

For safety reasons or to impart special functionalities, the glass substrate may advantageously be a laminated glass, consisting of an assembly of your glasses, in particular two glass sheets separated by a plastic sheet, such as polyvinyl butyral (PVB). Electrically conductive layers, which are thus heated by joule action, can be integrated on one of the sides of the laminate, which e.g. makes it possible to obtain heated floors and / or walls. The plastic sheet may likewise comprise liquid crystals which are suitable for aligning under the influence of an electric field, thereby enabling the transition from a transparent or opaque state, to a transparent state, such as e.g. can reveal a special decor, located on the back.

The glass substrate can also be a lighting glass pane, e.g. a double glazing, filled with a gas, in particular a noble gas such as xenon or neon, suitable to give rise to an electric field with light-emitting discharges, as described e.g. in application WO 2004/015739, which is incorporated herein by reference, or a laminated glass pane or multi-pane glass containing LEDs, which are electrically fed through thin conductive films, or by serigraphed bands or wires, e.g. on the basis of silver paste.

When the glass cladding is in the form of plates, the plates are preferably in the form of rectangles, the side dimensions of which are multiples of 15 cm, taking into account a joint of a given dimension (eg 3 mm). lvlan can thus form tiles of 15x15 cmz, 15x30cm2, 15x45 cmz, 30x45 omg, 30x20 cmz, 45x45 cmz etc. The fact that one counts a joint of a given dimension for each of these dimensions makes it possible to combine on the same wall tiles of different sizes, while maintaining a line orientation for the joints that is especially appreciated on the aesthetic level.

An advantage of the glass plate in relation to the traditional ceramic plates lies precisely in the modularity of the possible sizes and the possibility of easily obtaining plates of significant size. The final size is produced by simple cutting of large glass sheets, the surface of which can exceed 10 m2, while the dimensions of the ceramic tiles can only be modified by manufacturing and using molds of different sizes. In addition, it is extremely difficult to produce ceramic details on a large scale, e.g. those whose area exceeds 1 m2.

The shape of the edges of the tiles according to the invention has been optimized, in particular to improve the application of the joints and to avoid visible joint defects.

The inventors have observed that certain designs of edges, in particular of the "round joint" type, made it difficult to apply joints which uniformly covered the entire edge surface of the plate, whereby the transparency of the glass also made it possible to make any joint defects visible through the plate edge. The plates according to the invention thus preferably have obliquely cut edge surfaces, possibly sanded and / or polished, and which are characterized in that the obliquely cut width is larger at the front. The backing is preferably very little affected by the molding, in that the lacquer layer covers almost the entire surface of the plate. In particular, the width affected by the molding on the back is advantageously less than or equal to 0.5 mm, even less or equal to 0.3 mm. In general, the lacquered surface is preferably larger than the surface of the front after molding.

Cutting the glass plates according to the invention is particularly simple, and does not require other specific tool equipment is the tool equipment used for cutting ceramic plates. in particular glazed ceramic stoneware, or for cutting marble or granite. Likewise, the shaping of the edges after the cutting can be carried out by means of a polishing stone, according to methods well known to the specialists in laying ceramic tiles.

Let us again mention some technical advantages in relation to ceramic tiles: - the precision of the cutting is generally higher, which results in an increased possibility of keeping tight dimensional tolerances, - the possibility of applying varnish on tiles of large dimensions for the cutting of the tiles enables better reproducibility for decors, in particular of the hue, - the flatness is higher, thus making it possible to reduce the over-consumption of glue necessary to compensate for any excess space between the cladding and the wall.

The present invention will be more readily understood by reading the following detailed description of non-limiting embodiments, illustrated by the following figures: Figures 1 and 4 illustrate perspective views of various embodiments of the upholstery of the invention, Figures 2, 3, 5 illustrates in profile views of different embodiments of claddings according to the invention, Figures 6 - 10 illustrate different types of motifs, which can be made by etching with acid on the front of the cladding according to the invention.

Figure 1 shows a perspective view of a plate of square section. The plate comprises a monolithic clear glass sheet 1 of 6 mm thickness, the back of which is coated with a layer of lacquer 2 of 50 μm thickness, applied according to the curtain method.

The front has 3 acid-etched motifs in the form of right-angled parallelepipeds, which are regularly distributed in the plate's two right-angled directions.

Varnish 2 comprises, after drying, the following ingredients: - a binder in the form of polyurethane resin, prepared by crosslinking with a non-aromatic isocyanate, hydroxylated acrylic resins coming from the polymerization of an acrylic styrene - mineral materials (pigments and fillers) up to 55% by mass.

This varnish has been obtained by coating the curtain, followed by drying for a period of 5 minutes. The drying temperature is an important parameter for achieving a sufficiently low permeability to water. Under these special conditions and for a drying temperature of below 180 ° C, the permeability is too high, and after gluing to a wall by means of glue mortar, defects occur after a period of a few days, during drying of the mill. In this case, the stirring water from the adhesive penetrates the lacquer layer, which gives rise to a double release effect between the glass sheet and the lacquer layer and chemical attack on the surface of the glass. On the other hand, for a drying temperature higher than 180 ° C, the stronger crosslinking of the lacquer adhesive gives a weaker permeability to water, and generates no error after gluing with the adhesive.

Figure 2 shows a sample of a plate. The edges of the monolithic glass sheet 1 are shaped so as to show the edge surfaces 4, which are cut at an angle by removing the corners 5 and 6, this step being performed so that the lacquered surface 2 is lower than the surface of the front.

Figure 3 also illustrates a profile view of a plate. In this embodiment, the back of the coating is covered by a silver layer 7, by a silvering method.

The lacquer layer 2 covers this silver layer 7.

Figure 4 shows a perspective view of a plate formed by a laminated glass pane consisting of two glass sheets of 4 mm thickness, joined by a sheet of polyvinyl butyral 12 of 0.76 mm thickness. The front is etched with acid and has motifs 10 in the form of small waves. One of the glass sheets is cut in the drawing, in order to be able to show the presence of LEDs 11 (LED) on the surface of the polyvinyl butyral 13. Figure 5 illustrates a profile view of a wall cladding according to the invention, which shows a notch 12 of 3 mm width and 0.5 mm depth, made after painting, by grinding. A silvering layer 7 is applied and covers the lacquer surface 2 and the cut-in part 12. A second lacquer layer 2 (of a different composition) has then been applied to the entire silvered surface. From the front, the silver-plated layer 7 is thus only visible on the notch 12.

Figures 6 - 10 illustrate various motifs which are technically feasible by etching treatments with acid on the front of the wall claddings according to the invention. The darker parts represent the etched zones, which are thus seen deepened in relation to the clear parts, which are visible in relief.

The present invention has been described above by way of example. It will be appreciated that the person skilled in the art is able to carry out different variants of the invention without departing from the scope of the patent, as defined by the claims.

Claims (20)

10 15 20 25 30 35 531 452 ll PATENT REQUIREMENTS Wall cladding based on glass, in particular in the form of tiles, intended for cladding surfaces of a dwelling, such as walls, floors or ceilings, comprising a glass substrate which on the side to be applied is coated with a lacquer layer, characterized in that said lacquer has a permeability to water such that said coating can be applied to the surfaces by means of glue mortar or glue cement; that said lacquer has a permeability to water at 25 ° C which is lower than 10'6, in particular lower than 10'8, even lower than 1043 cm3.cm.cm 'zs ".Pa"' and that no fragments of glass , metal, sand, gravel, marble or any other inert material are attached to said varnish. Wall cladding according to Claim 1, characterized in that the lacquer comprises a synthetic resin as binder. Wall cladding according to one of the preceding claims, characterized in that the binder is based on polyurethane resin, in particular prepared by crosslinking a hydroxylated acrylic resin with an isocyanate or a polyisocyanate. Wall cladding according to Claim 2, characterized in that the binder is based on alkyd resin. Wall covering according to one of the preceding claims, characterized in that an adhesion promoter is present, in the form of layers, placed between the lacquer layer and the glass substrate, or dispersed in the lacquer. Wall cladding according to claim 5, characterized in that the adhesion promoter is based on silanes. Wall cladding according to one of the preceding claims, characterized in that a reflective layer, in particular of silver for mirrors, and / or a decoration, produced by serigra fi or ink jet, is placed between the lacquer layer and the glass substrate, optionally coated with an adhesion-promoting layer. Wall covering according to one of the preceding claims, characterized in that the lacquer layer comprises pigments which are resistant to ultraviolet radiation. Wall covering according to one of the preceding claims, characterized in that the lacquer layer comprises mineral fillers in a content, expressed as a percentage by mass, which is comprised between 40 and 70%. Wall cladding according to one of the preceding claims. characterized in that the glass substrate is a monolithic glass sheet. Wall cladding according to one of Claims 1 to 9, characterized in that 10 31 20 25 30 35 531 452 lfi. the glass substrate is a multi-glass pane comprising a plurality of glass sheets. Wall cladding according to one of the preceding claims, characterized in that the glass substrate on at least one of the sides has motifs in relief, produced by rolling and / or matting with acid and / or sandblasting and / or etching. Wall cladding according to one of the preceding claims, characterized in that the entire front of the glass substrate is matted with hydrofluoric acid or by sandblasting. Wall covering according to one of the preceding claims, characterized in that the glass substrate on at least one of the sides, preferably the front side, has at least one functional layer which imparts optical properties (stacks of anti-reflective layers) and / or anti-slip layers and / or surface layers (in particular anti-dirt properties, antibacterial, self-cleaning, hydrophobic, anti-fog, anti-scratch, anti-wear properties). Wall cladding according to claim 11, characterized in that the glass substrate is a double glass pane, filled with a gas which is suitable for giving rise to an electric field with light-emitting discharges. Wall cladding according to claim 11, characterized in that the glass substrate is a laminated glass pane or fl glass pane, containing LEDs. Wall covering according to one of the preceding claims, characterized in that the lacquered surface is larger than the surface of the front after molding. Wall cladding according to one of the preceding claims, characterized in that a portion of the back side is cut in by mechanical means and then coated with a decorative layer, preferably a silver layer, produced by classical silvering methods. Wall cladding according to Claim 18, characterized in that the incisions are made in the form of lines of 1 to 30 mm width and 0.5 to 3 mm depth and according to regularly distributed straight lines and according to two right-angled directions. A glass-based wall covering according to claim 1, comprising a decoration, produced by serigraphy or ink jet, applied to the back of a glass substrate.