Technical Field

The present disclosure relates in general to a decorative glass article and more particularly to a heat treatable decorative glass article.

Background

Decorative glass articles are generally used for interior applications to bring vibrant designs into our interior spaces. There are several products available in the market for this purpose. All known prior art products in the market are either annealed versions or have a pattern layer protected by an overcoat layer on a heat treated glass substrate. However the annealed products have a critical drawback of safety due to the possibility of the glass shattering into sharp pieces. In case of heat treated products having an overcoat layer, immediate tempering is required which may lead to difficulties in handling and processing. Moreover, such products may not allow easy handling of design printed enamels.

Further, there exists a need for a decorative product which can be handled easily and can be transported from the manufacturing site to an installation site without compromising the aesthetic nature of the decorative glass article and further can be cut to size and tempered at the installation site.

The current disclosure provides a decorative glass article with designs (patterns) that could be handled, transported and also capable of undergoing mechanical processing such as cutting, edge grinding, drilling, shaping etc. The current disclosure provides a decorative glass article having better mechanical properties than enameled/ lacquered glass prior to tempering and also capable of being handled and transported before the tempering process.

The decorative article of the current disclosure enhances the process speed, owing to the fact that glass of large sizes could be coated directly instead of being cut to specific sizes, coated and then tempered.

The decorative article of the current disclosure further can be transported before being cut into specific sizes and then subjected to processes including washing, grinding, drilling, shaping, toughening etc. This results in the reduction of coated glass wastage as the coated glasses could be cut, stored and used at a later date.

Summary of the Disclosure

In one aspect of the present disclosure, a heat treatable decorative article is provided. The heat treatable decorative article includes a glass substrate, a decorative pattern layer comprising an enamel comprising an inorganic oxides material, a resin and glass frits and a protective layer comprising an inorganic oxide material, a resin and glass frits. The decorative pattern layer is applied directly on one or both surface of the glass substrate and the protective layer is disposed above the decorative pattern layer.

In another aspect of the present disclosure, a heat treatable decorative article comprising a glass substrate and one or more protective layers comprising an inorganic oxide material, a resin and glass frits is disclosed. The protective layers are applied directly on at least one or both surface of the glass substrate covering at least 5% of the total surface area of the glass substrate.

In another aspect of the present disclosure, a method of making a heat treatable decorative article is provided. The method includes pre-treatment of a glass substrate, providing a patterned layer on a surface of the glass substrate and curing the patterned layer. The method further includes providing a coating of a protective layer over the patterned layer and curing the protective layer.

Other features and aspects of this disclosure will be apparent from the following description and the accompanying drawings.

Brief Description of the Drawings

Embodiments are illustrated by way of example and are not limited in the accompanying figures.

FIG. 1 illustrates a schematic cross-sectional view of a decorative glass article, in accordance with one embodiment of the present disclosure;

FIG. 2 illustrates a schematic cross-sectional view of a heat treatable decorative glass article, in accordance with another embodiment of the present disclosure; FIG. 3 illustrates a schematic cross-sectional view of a heat treatable decorative glass article having a decorative pattern layer comprising an enamel, in accordance with yet another embodiment of the present disclosure;

FIG. 4 illustrates a schematic cross-sectional view of a heat treatable decorative glass article, in accordance with yet another embodiment of the present disclosure;

FIG. 5A illustrates a decorative pattern, in accordance to one embodiment of the present disclosure;

FIG. 5B illustrates a decorative pattern, in accordance with one other embodiment of the present disclosure;

FIG. 6 illustrates a schematic cross-sectional view of a heat treatable decorative glass article, in accordance with yet another embodiment of the present disclosure;

FIG. 7 illustrates a flowchart for a method of manufacturing a decorative glass article, according to an embodiment of the present disclosure.

Skilled artisans appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the invention.

Detailed Description

Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or the like parts. Embodiments disclosed herein are related to a heat treatable decorative glass article.

The term "heat treatable decorative glass article" as used herein relates to a glass substrate having a decorative pattern created by a combination of a decorative pattern layer and a protective layer; or only using one or more layers of the protective layer having a good adhesion between the glass substrate and/ or the decorative pattern layer and is easy to handle, shape/cut to desired sizes and capable of being transported while retaining the aesthetics and durability before heat treatment and also adapted to undergo a thermal tempering and/or thermal hardening operation and/or other comparable heat treatment process without creating defects (e.g. aesthetical defects in the decorative pattern layer or protective layer). FIG. 1 illustrates a cross-sectional view of a decorative glass article 100 in accordance with an embodiment of the present disclosure. As shown, the decorative glass article 100 includes a glass substrate 110. The glass substrate 110 is provided with a decorative pattern layer 120 on one or both surface of the glass substrate 110. The decorative pattern layer 120 is protected by a protective layer 130 which is provided above the decorative pattern layer 120 as well as on the adjacent areas of the decorative pattern layer 120 on the glass substrate 110.

The glass substrate 110 of the current disclosure is a soda lime or a borosilicate glass. One or more surfaces of the glass substrate 110 is a clear, an extra clear, an acid etched or a sand blasted (on full surface or specific designs) surface. The glass substrate 110 as per certain example embodiments of the current disclosure is a laminated glass substrate with PVB, EVA or PET, a heat strengthened glass substrate, or a toughened glass substrate.

The thickness of the glass substrate 110 used herein as per certain example embodiments of the current disclosure is 6mm and it may further range between 0.5 mm to 19mm. The coating surface of the glass substrate 110 is prepared by polishing with Cerox, alumina or any other suitable abrasive powders. Optionally the glass substrate 110 is treated with solvents such as acetone or IPA.

The surface of the glass substrate 110 is further optionally treated with an adhesion promoter such as organsilanes, aminopropyltriethoxysilane, ethylester, propyloxymethylester, butyloxyethyl ester, or acrylate based resins such as acrylic acid. The adhesion promoter is added in a concentration ranging between 100 ppm to 10000 ppm.

The decorative pattern layer 120 comprises an enamel comprising an inorganic oxides material, a resin and glass frits. The decorative pattern layer comprises not more than 40 % of inorganic oxide material, not more than 20 % of a resin and not more than 85 % of glass frits.

The decorative pattern layer 120 covers at least 5% of the total surface area of the glass substrate 110. The thickness of the decorative pattern layer 120 ranges from 0.1μ-150μ. The organic content of the decorative pattern layer 120 ranges from 5 to 75 wt %. The viscosity of the coating ranges from 0.001 cP to 10 ⁹ cP. Optionally, an adhesion promoter is added to the decorative pattern layer 120 directly instead of being applied onto the glass. Additives such as thinners, for example, ethylester, propyloxymethylester, butyloxyethyl ester could also be added. The decorative pattern layer 120 is applied on the glass substrate 110 by screen printing, roller coating, curtain coating, digital printing, masking and spray painting or spray coating.

The decorative pattern layer 120 is smooth, transparent, opaque or matte finish coating. The decorative pattern layer 120 is applied as multiple layers or colors using any of the above mentioned coating techniques. The decorative pattern layer 120 may carry certain functionality such as having a metallic, phosphorence, fluorescence, or retro-reflection effect.

The decorative pattern layer 120 is cured by air drying, IR, UV or electron beam curing techniques. The temperature of curing ranges between 25 - 400 °C for IR. The UV curing is accomplished with Mercury vapor lamp (H type), Mercury vapor lamp with iron additive (D type), Mercury vapor lamp (V type), Xenon, UV LED's. The UV curing is initiated by cationic or free radical initiation mechanism. The electron beam curing is achieved by scanning or continuous beam.

The decorative pattern layer 120 is protected by a protective layer 130 provided above the decorative pattern layer 120 as well as on the adjacent areas of the decorative pattern layer 120 on the glass substrate 110. The protective layer 130 comprises of an inorganic oxide material, a resin and glass frits. The protective layer comprises not more than 40 % of inorganic oxide material, not more than 40 % of a resin and not more than 85 % of glass frits.

The thickness of the protective layer 130 ranges between 0.1μ-150μ. The organic content of the protective layer 130 ranges between 5 to 40 wt%. The viscosity of the protective layer 130 coating ranges between 0.001 cP to 10 ⁹ cP. The coating of the protective layer 130 is done using a bar coater. Alternatively, a similar result may be achieved by using other coating techniques such as digital printing, screen printing, roller coating curtain coating, spin coating, dip coating or spray coating.

The organic content of the decorative pattern layer 120 and the protective layer 130 comprises at least one or more materials selected from the group consisting of polyols, alkyds, acrylic, polyacrylic, polyacrylates, polymethacrylates, acrylamides, melamine, polycarbonates, acrylic-styrenes, vinyl- acrylic, urethanes, polyurethanes, polyesters, polyolefines, urethane alkyds, polyurea, amino resins, polyamides, epoxies, epoxy esters, phenolic resins, silicon resins, PVC, PVB, water-based resins and reaction products of photocurable chemicals The inorganic oxide material comprises of pigments which are selected based on the desired coloration. For example, titanium oxide of any suitable stoichiometry (e.g., titania or Ti0 ₂ ) was used for white paints. As another example, chromium oxide, copper oxide, and/or other materials of any suitable stoichiometry may be used for black paints.

The coating of the protective layer 130 is either a single layer or multiple layer coating. The coating of the protective layer 130 is an organic, an inorganic or a hybrid coating. The coating of the protective layer 130 is used to enhance the aesthetic/ functional application of the underlying decorative pattern layer 120. The coating comprising varied combinations of decorative pattern layer 120 and protective layer 130 create a decorative pattern 140 on the glass substrate as depicted in FIG. 5A and FIG. 5B.

In alternate embodiments, the decorative pattern 140 can be obtained in various colours and shapes using only one protective layer 130 as illustrated in FIG. 4. In one aspect of this embodiment, the protective layer 130 covers at least 5% of the total surface area of the glass substrate 110. In yet another embodiment, the decorative pattern 140 can be obtained in various colours and shapes using two protective layers 130 as illustrated in FIG. 6. In one aspect of this embodiment, the protective layer 130 provided directly over the glass substrate 110 covers at least 5% of the total surface area of the glass substrate 110 to form the decorative pattern 140, whereas another layer of protective layer 130 provided as over layer, which covers the decorative pattern 140 and the glass substrate 110. The decorative pattern 140 created using a protective layer 130 as illustrated in FIG. 4 is heat treatable, also transportable, and further capable of withstanding various processing steps such as grinding, bending etc. Similarly The decorative pattern 140 created using a protective layer 130 along with an over layer of protective layer 130 as illustrated in FIG. 6 is heat treatable and also transportable and further capable of withstanding various processing steps such as grinding, bending etc.

The decorative glass article 100 comprising the decorative pattern layer 120 of the current disclosure is coated with a protective layer 130 which can be heat treated at high temperature. The heat treatment process involves heating or exposing the decorative glass article carrying the coating to a temperature greater than about 600 °C for a period ranging between 2 minutes and 20 minutes, preferably for a maximum period of 15 minutes, depending, inter alia, on the type of oven and on the thickness of the decorative glass article 100. The coating of the protective layer 130 melts to form a permanent protective layer above the decorative pattern layer 120 as well as on the adjacent areas of the decorative pattern layer 120 on the glass substrate 110.

The decorative glass article of the current disclosure can be handled and transported both before and after heat treatment without damaging the decorative pattern layer 120 or the protective layer 130. For instance, the decorative glass article 100 which is coated with a protective layer 130 may be cut, ground, have holes drilled therein, etc., without causing the decorative pattern layer 120 to peel off or to become damaged at the borders of the cutting line and drilling hole edges, both before and after heat treatment. The decorative glass article 100 of the current disclosure also offer good water resistance, and the decorative pattern layer 120 does not peel off or degrade during edge grinding, polishing, storage, transportation, etc.

FIG. 2 illustrates a schematic cross-sectional view of a decorative glass article 100 in accordance with certain example embodiments of the current disclosure. The glass substrate 110 is provided with a coating 200 comprising a stack of thin functional layer 210 and optionally one or more over-layers 220.

The decorative glass article 100 of certain example embodiments comprises of a coating 200 wherein the functional layer 210 is selected from metals and/ or their alloys belonging to a group consisting of niobium, silver, chromium, nickel, tantalum, and zirconium and further comprise of one or more over-layers 220.

The glass substrate 110 is further provided with a decorative pattern layer 120 above the coating 200. The decorative pattern layer 120 comprises of an enamel comprising an inorganic oxides material, a resin and glass frits. The decorative pattern layer 120 comprises not more than 40 % of inorganic oxide material, not more than 20 % of a resin and not more than 85 % of glass frits.

The decorative pattern layer 120 covers at least 5% of the total surface area of the glass substrate 110. The thickness of the decorative pattern layer 120 ranges from 0.1μ-150μ. The organic content of the decorative pattern layer 120 ranges from 5 to 75 wt %. The viscosity of the coating ranges from 0.001 cP to 10 ⁹ cP. The decorative pattern layer 120 is applied on the glass substrate 110 by screen printing, roller coating, curtain coating, digital printing, masking and spray painting or spray coating. The decorative pattern layer 120 is protected by a protective layer 130 provided above the decorative pattern layer 120 as well as on the adjacent areas of the decorative pattern layer 120 on the glass substrate 110. The protective layer 130 comprises of an inorganic oxide material, a resin and glass frits. The protective layer comprises not more than 40 % of inorganic oxide material, not more than 40 % of a resin and not more than 85 % of glass frits.

The thickness of the protective layer 130 ranges between 0.1μ-150μ. The solid content of the protective layer 130 ranges between 5 to 40 wt%. The viscosity of the protective layer 130 ranges from 0.001 cP to 10 ⁹ cP. The coating of the protective layer 130 is done using a bar coater. Alternatively, a similar result may be achieved by using other coating techniques such as digital printing, screen printing, roller coating curtain coating, spin coating, dip coating or spray coating.

The organic content of the decorative pattern layer 120 and the protective layer 130 comprises at least one or more materials selected from the group consisting of polyols, alkyds, acrylic, polyacrylic, polyacrylates, polymethacrylates, acrylamides, melamine, polycarbonates, acrylic-styrenes, vinyl- acrylic, urethanes, polyurethanes, polyesters, polyolefines, urethane alkyds, polyurea, amino resins, polyamides, epoxies, epoxy esters, phenolic resins, silicon resins, PVC, PVB, water-based resins and reaction products of photocurable chemicals

The inorganic oxide material comprises of pigments which are selected based on the desired coloration. For example, titanium oxide of any suitable stoichiometry (e.g., titania or Ti02) was used for white paints. As another example, chromium oxide, copper oxide, and/or other materials of any suitable stoichiometry may be used for black paints.

The coating of the protective layer 130 is either a single layer or multiple layer coating. The coating of the protective layer 130 is an organic, an inorganic or a hybrid coating. The coating of the protective layer 130 is used to enhance the aesthetic/ functional application of the underlying decorative pattern layer 120. The coating comprising varied combinations of decorative pattern layer 120 and protective layer 130 create a decorative pattern 140 on the glass substrate as depicted in FIG. 5A and FIG. 5B.

The decorative glass article 100 comprising the decorative pattern layer 120 of the current disclosure is coated with a protective layer 130 which can be heat treated at high temperature. The heat treatment process involves heating or exposing the decorative glass article carrying the coating to a temperature greater than about 600 °C for a period ranging between 2 minutes and 20 minutes, preferably for a maximum period of 15 minutes, depending, inter alia, on the type of oven and on the thickness of the decorative glass article 100.

The coating of the protective layer 130 melts to form a permanent protective layer above the decorative pattern layer 120 as well as on the adjacent areas of the decorative pattern layer 120 on the glass substrate 110.

The decorative glass article 100 which is coated with the protective layer 130 may be cut, ground, have holes drilled therein, etc., without causing the decorative pattern layer 120 to peel off or become damaged at the borders of the cutting line and drilling hole edges, both before and after heat treatment.

FIG. 3 illustrates a schematic cross-sectional view of a decorative glass article 100 having a decorative pattern layer 410 comprising an enamel layer in accordance with certain example embodiments of the current disclosure. The glass substrate 110 is provided with a decorative pattern layer 410 comprising an enamel on one or both surfaces of the glass substrate 110. The decorative pattern layer 410 is applied using an enamel covering at least 5% of the surface area of the glass substrate 110. The enamel thickness ranges between 0.1μ-150μ. The organic content of the decorative enamel layer 410 ranges between 5 to 45wt%.

The enamel is applied by screen printing, roller coating, curtain coating, digital printing, masking and spray painting or spray coating.

The decorative pattern layer 410 comprising an enamel layer is protected by a protective layer 130 provided above the decorative pattern layer 410 as well as the adjacent areas of the decorative pattern layer 410 on the glass substrate 110. The protective layer 130 comprises of an inorganic oxide material, a resin and glass frits. The protective layer comprises not more than 40 % of inorganic oxide material, not more than 40 % of a resin and not more than 85 % of glass frits.

The thickness of the protective layer 130 ranges between 0.1μ-150μ. The organic content of the protective layer 130 ranges between 5 to 40 wt%. The viscosity of the protective layer 130 coating ranges between 0.001 cP to 10 ⁹ cP. The coating of the protective layer 130 is done using a bar coater. Alternatively, a similar result may be achieved by using other coating techniques such as digital printing, screen printing, roller coating curtain coating, spin coating, dip coating or spray coating. The coating of the protective layer 130 is either a single layer or multiple layer coating. The coating of the protective layer 130 could either be an organic/ inorganic/ hybrid coating. The coating of the protective layer 130 could be used to enhance the aesthetic/ functional application of the underlying decorative pattern layer 410. The coating comprising varied combinations of decorative pattern layer 410 and protective layer 130 create a decorative pattern 140 on the glass substrate as depicted in FIG. 5A and FIG. 5B.

The decorative glass article 100 comprising the decorative pattern layer 410 of the current disclosure is coated with a protective layer 130 which can be heat treated at high temperature. The heat treatment process involves heating or exposing the decorative glass article carrying the coating to a temperature greater than about 600 °C for a period ranging between 2 minutes and 20 minutes, preferably for a maximum period of 15 minutes, depending, inter alia, on the type of oven and on the thickness of the decorative glass article 100.

The coating of the protective layer 130 melts to form a permanent protective layer above the decorative pattern layer 410 as well as on the adjacent areas of the decorative pattern layer 410 on the glass substrate 110.

The decorative glass article 100 which is coated with a protective layer 130 may be cut, ground, have holes drilled therein, etc., without causing the decorative pattern layer 410 to peel off or become damaged at the borders of the cutting line and drilling hole edges, both before and after heat treatment.

As mentioned earlier, the decorative pattern 140 illustrated in FIG. 5A and 5B in accordance with certain example embodiments of the current disclosure are provided to assist in understanding the teachings disclosed herein and should not be interpreted as a limitation to the scope or applicability of the teachings. However, other decorative patterns 140 may certainly be implemented using the various embodiment of this disclosure.

FIG. 7 depicts a flowchart showing a method 700 that may be used to make the decorative glass article 100 in accordance with certain example embodiments. The current disclosure provides a method 700 of making a heat treatable decorative article 100, the method 700 comprises the steps of 710 - 750. In step 710 the glass substrate 110 is pre-treated. The glass substrate is cleaned and applied with an adhesion promoter. In step 720, a decorative pattern layer 120 is applied on one or both surface of the glass substrate 110. In step 730, the glass substrate applied with the decorative pattern layer 120 is cured at 150 °C in an oven. In step 740, the cured glass substrate 110 having the decorative pattern layer 120 is coated with a protective layer 130 over the decorative pattern layer 120. In the final step 750, the glass substrate provided with the decorative layer 120 and protective layer 130 is cured at 180 °C in an oven. Optionally, in an alternate embodiment of the method 700, a primer layer is applied before applying a protective layer 130.

The glass substrate 110 of the current disclosure is a soda lime or a borosilicate glass. One or more surfaces of the glass substrate 110 is a clear, extra clear, acid etched or sand blasted (on full surface or specific designs). The glass substrate 110 as per certain example embodiments of the current disclosure is a laminated glass substrate with PVB, EVA or PET, a heat strengthened glass substrate, or a toughened glass substrate.

The thickness of the glass substrate 110 used herein as per certain example embodiments of the current disclosure is 6mm and it may further range between 0.5 mm to 19mm. The coating surface of the glass substrate 110 is prepared by polishing with Cerox, alumina or any other suitable abrasive powders. Optionally the glass substrate 110 is treated with solvents such as acetone or IPA.

The surface of the glass substrate 110 is optionally treated with an adhesion promoter such as organsilanes, aminopropyltriethoxysilane, ethylester, propyloxymethylester, butyloxyethyl ester, or acrylate based resins such as acrylic acid. The adhesion promoter is added in a concentration ranging between 100 ppm to 10000 ppm.

The decorative pattern layer 120 comprises an enamel comprising an inorganic oxides material, a resin and glass frits. The decorative pattern layer 120 comprises not more than 40 % of inorganic oxide material, not more than 20 % of a resin and not more than 85 % of glass frits.

The decorative pattern layer 120 is applied not more than 95% of the surface area on one or both surfaces of the glass substrate 110. The thickness of the decorative pattern layer 120 ranges from 0.1μ-150μ. The organic content of the decorative pattern layer 120 ranges from 5 to 75 wt %. Optionally, an adhesion promoter is added to the paint directly instead of being primed onto the glass. Additives such as thinners, for example, ethylester, propyloxymethylester, butyloxyethyl ester could also be added. The decorative pattern layer 120 is applied by screen printing, roller coating (single, double, offset, rotary, gravure roller, flexography), curtain coating, digital printing, masking and spray painting or spray coating.

The decorative pattern layer 120 is smooth, transparent or matte finish coating. The decorative pattern layer 120 is applied as multiple layers or colors using any of the above mentioned coating techniques. The decorative pattern layer 120 may carry certain functionality such as having a metallic effect, phosphorence, fluorescence, or retro-reflection.

The decorative pattern layer 120 is cured by air drying, IR, UV or electron beam curing techniques. The temperature of curing ranges anywhere between 25 - 400°C for IR. The UV curing is accomplished with Mercury vapor lamp (H type), Mercury vapor lamp with iron additive (D type), Mercury vapor lamp (V type), Xenon, UV LED's. The UV curing is initiated by cationic or free radical initiation mechanism. The electron beam curing is achieved by scanning or continuous beam.

The decorative pattern layer 120 is protected by a protective layer 130 provided above the decorative pattern layer 120 as well as on the adjacent areas of the decorative pattern layer 120 on the glass substrate 110. The protective layer 130 comprises of an inorganic oxide material, a resin and glass frits. The protective layer comprises not more than 40 % of inorganic oxide material, not more than 40 % of a resin and not more than 85 % of glass frits.

The thickness of the protective layer 130 ranges between 0.1μ-500μ. The organic content of the protective layer 130 ranges between 5 to 40 wt %. The viscosity of the protective layer 130 coating ranges between 0.001 cP to 10 ⁹ cP. The coating of the protective layer 130 is done using a bar coater. Alternatively, a similar result may be achieved by using other coating techniques such as digital printing, screen printing, roller coating (curtain coating, spin coating, dip coating or spray coating.

The coating of the protective layer 130 is either a single layer or multiple layer coating. The coating of the protective layer 130 is an organic, an inorganic or a hybrid coating. The coating of the protective layer 130 is used to enhance the aesthetic/ functional application of the underlying layer decorative pattern layer 120. The coating comprising varied combinations of decorative pattern layer 120 and protective layer 130 create a decorative pattern 140 on the glass substrate as depicted in FIG. 6 A and FIG. 6B.

Examples Example 1

In accordance with the current example embodiments of the current disclosure, a glass substrate 110 of 5 mm thick was used to create a heat treatable decorative glass article 100 of the current disclosure.

Pre-treatment of the glass substrate

The glass substrate was polished in one or both surface with 3 wt % Ceria solution. After polishing, the glass substrate was thoroughly cleaned with water to remove any particles on the surface. After further cleaning the surface, the glass substrate was treated with an adhesion promoter (aminopropyltriethoxysilane). The adhesion promoter was applied by simply wiping the silane directly onto the glass substrate. Samples were prepared and the concentration of the adhesion promoter used for the surface preparation was varied from 1000-4000 ppm. Preparation of decorative pattern layer

In accordance with the current example embodiments of the current disclosure, the decorative pattern was prepared using an enamel having the following composition:

Glass frit fluxes (50-85 wt %)

ZnO-B ₂ 0 ₃ -Si0 ₂

Bi ₂ 0 ₃ -B ₂ 0 ₃ -Si0 ₂

Other oxides: Ti02, Zr0 ₂ , A1 ₂ 0 ₃ , Na ₂ 0, K ₂ 0, Li ₂ 0, CaO, F

Inorganic pigments (10-40 wt %)

CuCr ₂ 0 ₄

(Ni,Fe)(Cr,Fe) ₂ 0 ₄

(Co,Fe)(Fe,Cr) ₂ 0 ₄

Modifiers: CuO, MnO or others

Additive oxides, sulfides, or metals (0-20 wt %)

Coating methods

Two different coating methods were used to print the decorative pattern layer comprising an enamel on the glass substrate viz., screen printing and engraved roller coating. The coated samples were then cured at 150 °C in an oven.

Preparation of protective layer The protective layer comprising not more than 40 % inorganic oxide material, not more than 40 % resin and not more than 85 % glass frits was prepared and applied using a bar coater. After the coating was performed the glass substrate was cured at 180 °C in an oven. Preparation of Samples

Sample 1 was prepared according to the teachings associated with FIG. 3. Sample 2 was prepared according to the teachings associated with described in FIG. 4 and sample 3 was prepared according to the teachings associated with described in FIG. 6.

Durability Studies

The overall durability study of the coating was performed using various parameters.

Brush test

Brush test was used to evaluate the resistance of the coating to erosion caused by scrubbing. Full details of this test are set out in ASTM Standard D 2486 - 00. Samples of coated glass were submitted to Test Method A. The sample was scrubbed dry, with a bristle brush until the coating was pierced.

Taber Abrasion test

Taber abrasion test was used for performing accelerated wear resistance testing. It involved mounting a flat sample of approximately 100 mm to a turntable platform that rotate on a vertical axis at a fixed speed. The wear action was carried out by two rotating abrading wheels supported on a loading arm which applied 250 gram pressure against the specimen, exclusive of the weight of the wheel in contact with sample. The weight before and after the test was measured to calculate the overall weight loss of the test sample.

Lucite test

Lucite test was used to evaluate the scratch resistance of the coating. The sample was sprinkled on the coating side, with Lucite® 4F or 47G (a quarter of a tea spoon on a sample of 15 x 25 cm), and then covered with a piece of clear glass of 6mm thick (10 x 10 cm) on which a weight of 1 kg was placed. The assembly "upper glass and weight" was subjected to a backward and forward movement during 100 cycles or more and kept on a lab shaker.

Adhesion test

The adhesion testing was performed by the cross hatch test method that assessed the resistance of paint coatings to separation from substrates when a right-angle lattice pattern was cut into the coating and penetrated through the substrate. Depending on visual observation of the area of the coating where the paint separated from the substrate the resulting coating was classified into Classes 0 (none of the square lattices are detached) to 5 (more than 65% area of the squares are detached).

Condensation test

The condensation test was used to control the behavior of the sample in humid ambient atmospheres and to pinpoint defects in the protection of the sample against corrosion. The sample was placed in a relative humidity of 98% at a temperature of 40 °C for a period of 3 days. No blistering, i.e. local peeling off of the coating was visible after the test.

Scratch resistance

The scratch resistance test was used to determine the surface hardness of the sample using a scelerometer. The scelerometer consists of a cursor with a screw lock, a round tungsten carbide tip that is compressed by different springs. The spring force was adjusted by a collar, whereby compressing the spring increased the force with which the tip was pushed on to the surface of the test piece. The tungsten carbide tip was slowly moved over the coated surface with a defined constant pressure. A visual mark that was visible on the glass side i.e the side opposite to the coated surface indicated a fail in the surface hardness or wear/scratch resistance.

The results of the durability study are provided in Table 1.

Table 1 : Results of the Durability Studies

using CS- 10F wheel

Lucite

No surface

test(Weight

No defects on the defects were

I Kg, Pass Pass

glass side seen on the

Duration

glass side

60 min)

No defects seen

after Immersion

Adhesion of sample (25x35

No defects

in presence mm) in tap water Pass Pass

were seen

of water for 6 min, drying

& peel off using

normalized tape

Adhesion

test(Cross- cut test 6 < 4 3 2 3 to 4

teeth

(2mm)

High

Humidity

(Temp:40° Visual defects,

Pass

C, R.H.: No Blistering Pass Pass

95% for 3

days)

Scratch

>4N IO N 4N 4N

Resistance

Thus the current disclosure provides a decorative glass article that can be coated, then cut, and then heat treated, which provides various advantages while transporting and installing. The good durability of the protective layer before tempering and post tempering adds flexibility to the manufacturing process, that is an intermediate product can be shipped to a fabricator before finishing (e.g., sizing) and/or heat treatment, essentially enabling intermediate products to be handled and/or otherwise processed as if they were conventional float glass substrates.

Industrial applicability The heat treatable decorative article of the current invention may be used as wall claddings for lift lobbies, offices, restaurants and residential spaces including doors, partitions, table furniture, facades, kitchen splashbacks and tiles for flooring.

Note that not all of the activities described above in the general description or the examples are required, that a portion of a specific activity may not be required, and that one or more further activities may be performed in addition to those described. Still further, the order in which activities are listed is not necessarily the order in which they are performed.

Benefits, other advantages, and solutions to problems have been described above with regard to specific embodiments. However, the benefits, advantages, solutions to problems, and any feature(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential feature of any or all the claims.

The specification and illustrations of the embodiments described herein are intended to provide a general understanding of the structure of the various embodiments. The specification and illustrations are not intended to serve as an exhaustive and comprehensive description of all of the elements and features of apparatus and systems that use the structures or methods described herein. Certain features, that are for clarity, described herein in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features that are, for brevity, described in the context of a single embodiment, may also be provided separately or in a sub combination. Further, reference to values stated in ranges includes each and every value within that range. Many other embodiments may be apparent to skilled artisans only after reading this specification. Other embodiments may be used and derived from the disclosure, such that a structural substitution, logical substitution, or another change may be made without departing from the scope of the disclosure. Accordingly, the disclosure is to be regarded as illustrative rather than restrictive.

The description in combination with the figures is provided to assist in understanding the teachings disclosed herein, is provided to assist in describing the teachings, and should not be interpreted as a limitation on the scope or applicability of the teachings. However, other teachings can certainly be used in this application.

As used herein, the terms "comprises," "comprising," "includes," "including," "has," "having" or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a method, article, or apparatus that comprises a list of features is not necessarily limited only to those features but may include other features not expressly listed or inherent to such method, article, or apparatus. Further, unless expressly stated to the contrary, "or" refers to an inclusive-or and not to an exclusive-or. For example, a condition A or B is satisfied by any one of the following: A is true (or present) and B is false (or not present), A is false (or not present) and B is true (or present), and both A and B are true (or present).

Also, the use of "a" or "an" is employed to describe elements and components described herein. This is done merely for convenience and to give a general sense of the scope of the invention. This description should be read to include one or at least one and the singular also includes the plural, or vice versa, unless it is clear that it is meant otherwise. For example, when a single item is described herein, more than one item may be used in place of a single item. Similarly, where more than one item is described herein, a single item may be substituted for that more than one item.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The materials, methods, and examples are illustrative only and not intended to be limiting. To the extent that certain details regarding specific materials and processing acts are not described, such details may include conventional approaches, which may be found in reference books and other sources within the manufacturing arts.

While aspects of the present disclosure have been particularly shown and described with reference to the embodiments above, it will be understood by those skilled in the art that various additional embodiments may be contemplated by the modification of the disclosed machines, systems and methods without departing from the spirit and scope of what is disclosed. Such embodiments should be understood to fall within the scope of the present disclosure as determined based upon the claims and any equivalents thereof.

List of Elements

TITLE: Decorative Glazing

100 Heat treatable decorative glass article

110 Glass substrate

120 Decorative pattern layer

130 Protective layer

140 Decorative pattern

200 Coating

210 Functional layer

220 Over-layer

410 Decorative pattern layer comprising an enamel layer

700 Method

710 Step

720 Step

730 Step

740 Step

750 Step