Use of glazing having two stacked enamel layers, the first of which has a pattern and the second of which is flat and covers the pattern, to produce a textured haptic effect

Abstract

The invention relates to a use of single or multiple monolithic or laminated glazing, one face of a constituent glass sheet of which is coated with at least one first enamel layer of a first colour in a pattern, then with a second enamel layer of a second colour which is different from the colour(s) of the at least one first enamel layer, the second enamel layer flatly covering the pattern of the at least one first enamel layer, at least in part, so as to produce a textured haptic effect. The invention also relates to a method for manufacturing glazing for this use.

Description

[0001] Description

[0002] Title of the invention: Use of glazing with two superimposed layers of enamel, the first in a pattern and the second flat covering the pattern, to produce a haptic texturing effect

[0003] The invention relates to glazing for buildings, but more particularly to glazing for land, water and air vehicles, especially rear windows, side windows, windshields and roofs for automobiles. There is a growing demand for decoration of automotive glazing to create differentiation and increased appeal on the market. The term "decoration" here refers to any figurative aesthetic pattern, without possibly excluding information in the form of text, barcode, QR code, as well as their colors.

[0004] More specifically, the invention aims to provide glazings which, seen from one side, have a seamless appearance with the mounting environment, and seen from the other side, a texturing, depth, relief effect mentally evoking the sense of touch without physically activating it, this effect being designated by the term "haptic". The seamless appearance with the mounting environment has a color matching component of the glazing to that of the mounting environment. This does not exclude the glazing having several colors, possibly in color gradients. The seamless appearance with the mounting environment also includes, for example, the adaptation of the shape of the decoration on the glazing to the possibly three-dimensional geometry of the glazing and its contour (periphery), therefore, for example, to the geometry of the bodywork opening.

[0005] These visual and haptic effects are obtained by the present invention which, consequently, has as its object the use of a monolithic or laminated glazing, single or multiple, of which one face of a constituent glass sheet is coated with at least a first layer of enamel of a first color according to a pattern, then with a second layer of enamel of a second color different from the color(s) of the at least one first layer of enamel, the second layer of enamel covering flat at least in part the pattern of at least one first layer of enamel, to produce a haptic texturing effect.

[0006] Monolithic glazing consists of a single sheet of glass, while laminated glazing comprises several sheets of glass bonded two by two by an interlayer adhesive layer such as polyvinyl butyral (PVB). Single glazing refers to such monolithic or laminated glazing, as opposed to multiple glazing (double, triple, etc.) which refers to a set of several panes of glass held at their periphery with a certain spacing from each other, each spacing constituting a layer of air or gas, for example, in communication with means of drying the air or gas. These multiple structures have a thermal and acoustic insulation function, particularly for buildings and refrigeration. . .

[0007] For the purposes of the invention, an enamel is a mineral layer whose precursor composition comprises at least one pigment and at least one glass frit (containing, for example, bismuth borosilicate, or bismuth and zinc borosilicate), an organic medium intended to facilitate the application of the composition to the substrate as well as its temporary adhesion to it, and which is removed during the firing of the enamel; the medium comprises solvents, diluents, oils and / or resins. The enamels preferably do not comprise lead oxide. The enamels can have any type of color, black, white, blue. . .

[0008] Because the second color of the second enamel layer is chosen to be different from the color(s) of the at least one first enamel layer while covering flat (continuous enameled surface, full local face) at least part of the pattern of the first enamel layer(s), this part of the pattern is clearly visible on the side opposite the enameled face of the glass sheet, standing out clearly from the flat of the second enamel layer with contrast. A judicious choice of color(s) of the at least one first enamel layer identical to or close to that of the mounting environment on the side opposite the enameled face of the glass sheet, creates, seen from this side, an impression of continuity between the mounting environment (for example, automobile bodywork) and the glazing.Seen from the side of the enameled face of the glass sheet, the covering of at least part of the pattern of the first layer(s) of enamel by the second layer of enamel in a flat manner produces a visual effect of haptic texturing (depth, relief, “material” effect).

[0009] Preferably, the glass sheet is flat or curved, made of mineral glass of the float, soda-lime, aluminosilicate, borosilicate type, clear or tinted, possibly hardened, thermally toughened or chemically strengthened. Tinted glass includes coloring agents such as iron oxide, cobalt oxide, chromium oxide, nickel oxide, selenium.

[0010] Preferably, the glass sheet coated with the enamel layers is laminated by bonding to another glass sheet by means of an interlayer adhesive layer of polyvinyl butyral (PVB), polyurethane (PU), ethylene vinyl acetate (EVA), casting resin or ionomer, the face of the glass sheet coated with the enamel layers being oriented towards this interlayer adhesive layer.

[0011] Preferably, the second layer of enamel is based on bismuth silicate, bismuth borosilicate or bismuth borate, or bismuth zinc silicate, bismuth zinc borosilicate or bismuth zinc borate. These compositions generally give so-called "anti-stick" enamels, i.e. substantially reducing the occurrence of sticking during bending (transfer of enamel from one sheet of glass to another by contact during their simultaneous bending).

[0012] The invention also relates to a method of manufacturing glazing for a use described above, characterized in that it comprises the operations consisting of:

[0013] - depositing on one side of a sheet of mineral glass a first layer of enamel precursor or several first layers of enamel precursor of different colors according to a pattern,

[0014] - drying the first or all of the first layer(s) of enamel precursor one by one before depositing the next, and / or in groups of several of them, or all simultaneously,

[0015] - deposit a second layer of enamel precursor of a color different from that(s) of the enamel(s) of the first layer(s), flat, at least partially covering the pattern of the first layer(s) of enamel, and

[0016] - cook the enamels.

[0017] According to a preferred characteristic of the method of the invention, the wet thickness of the or each first layer of enamel precursor is between 20 and 28 pm and that of the second layer of enamel precursor between 20 and 28 pm or between 38 and 46 pm if the or a first layer of enamel precursor contains metallic or dichroic pigments.

[0018] Preferably, the deposition of the enamel precursor layers is carried out by printing techniques such as screen printing, in particular in a single pass for each layer, digital printing such as inkjet, roller transfer. Preferably, drying is carried out between 140 and 180 °C for 1 to 3 min, in particular by means of an infrared dryer.

[0019] Preferably, the firing of the enamels is carried out between 590 and 690°C, in particular for 100 to 600 seconds for a thickness of the glass sheet between 2.1 and 3.85 mm.

[0020] Preferably, the mineral glass sheet is subjected to a bending, thermal toughening or chemical strengthening treatment and / or lamination to another glass sheet, the face of the glass sheet coated with the enamel layers being in the latter case oriented towards an interlayer adhesive layer, treatment in which the baking of the enamels is integrated. The invention is now illustrated by the following examples, in relation to the appended drawings in which [Fig. 1] and [Fig. 2], respectively [Fig. 3] and [Fig. 4], respectively [Fig. 5] and [Fig. 6] represent a glazing of the invention obtained in Test No. 1, respectively 2, respectively 3 described below, seen from the side opposite the enameled face (Figures 1, 3, 5) and from the side of the enameled face (Figures 2, 4, 6).

[0021] Examples

[0022] Sheets of clear mineral glass on the one hand, tinted on the other, and of thickness equal to 2.1 mm on the one hand, 3.85 mm on the other hand, are successively coated with a white, blue colored enamel... according to a pattern, then with black enamel on the full face. The nature of the successive enamel coatings is divided into three tests described in the table below.

[0023] Table 1]

[0024] PEMCO DV778380 is the reference for white enamel marketed by Prince Minerals Italy Sri (Italy); the pigments are based on titanium dioxide, notably crystallized in the rutile form. TDF9646 is the reference for blue enamel marketed by Vibrantz (formerly Ferro GmbH) (Germany).

[0025] A dichroic enamel is an enamel that contains dichroic pigments. These pigments generally have an interference structure comprising at least one metallic reflective layer and at least one dielectric transparent layer. The interference structure produces the dichroic effect, typically via a dielectric stack of layers with different refractive indices or by the combination of dielectric transparent layer(s) and semi-opaque metallic layer(s). The metallic reflective layer is usually made of aluminum, but can also be formed of gold, copper or silver. The dielectric transparent layer can be formed of silica, magnesium fluoride or aluminum oxide. Ocean Blue 201003 is the reference of the dichroic blue enamel marketed by Ceramic Colors Wolbring GmbH (Germany).Each of the three aforementioned enamels is applied in a wet thickness of 24±2 μm as a first layer of enamel according to the invention, forming a pattern, respectively a logo including the Eiffel Tower with text, an alignment of rows of dots, and an alignment of rows of triangles.

[0026] Then the first layer of enamel is dried at 160°C for 2 min.

[0027] Then the second layer of enamel is applied so as to cover the patterns of the first layer of enamel in wet thicknesses of 24±2 pm (Tests Nos. 1 and 2) and 42±2 pm (Test No. 3). A black enamel is an opaque layer which is not normally electrically conductive. The black tint preferably corresponds to a clarity in reflection on the glass side (L*, illuminant D65, CIE-1964 reference observer) of less than 10, in particular less than 5. The pigments preferably comprise one or more oxides chosen from chromium, copper, iron, manganese, cobalt and nickel oxides. These may be, for example, copper and / or iron chromates. These pigments impart a black tint. FENZI 1L6026 is the reference of the black enamel marketed by Johnson Matthey Advanced Glass Technologies BV (Netherlands). 14501 is the reference of the black enamel marketed by Vibrantz (formerly Ferro GmbH) (Germany).

[0028] The enamels are fired at 600-640°C for 200 to 250 seconds for a 2.1 mm thick glass sheet, 400 to 450 seconds for a 3.85 mm thick glass sheet. This treatment is compatible with integration into glass sheet transformation processes for manufacturing automotive glazing, including bending, thermal toughening or chemical strengthening, and lamination. The invention is of secondary interest in the case of bending in which the enameled face of the glass sheet, originally flat, is in contact with another flat glass sheet, with the aim of bending the two glass sheets simultaneously to a strictly identical three-dimensional geometry; the process may be gravity bending in which the assembly of the two superimposed glass sheets is supported only at its periphery by a frame called a skeleton, or bending by pressing.Indeed, the first layers of enamel used above present the risk of a partial transfer onto the other sheet of glass during bending by contact effect under the application of high temperatures. Under these conditions, it is interesting that the second layer of enamel (deposited on the full face) has a property of limiting or even eliminating this transfer of enamel onto the other sheet (in English "anti-stick"). This is the case of the enamels used above as a second layer of enamel.

[0029] In the context of the use of the glazing of the invention as laminated automotive glazing, possibly laminated, it is envisaged in particular to enamel the inner face of the sheet (outer), called Face 2, Face 1 being the face of the glazing in contact with the external atmosphere, Face 3 the face facing the outside of the second sheet of glass starting from the outside. . . Thus, during gravity bending in particular, the enameled glass sheet is positioned under the second sheet of glass, with its enameled face upwards in contact with the second sheet of glass. This enameled face constitutes the concave Face 2 of the outer sheet of an automobile windshield for example.

[0030] Referring to Figure 1, on the opposite side to the face of the enameled glass sheet (exterior of the automobile) of Test No. 1 above, we see the white design (first layer of enamel) of a city including the Eiffel Tower, and the black background. If the body of the automobile is white, a continuity effect between it and the glazing can be produced. Figure 2 is misleading. Seen from the interior of the automobile (Figure 2), although the background appears white in the Figure (reproducing the lighting conditions of a photo taken from the passenger compartment, daylight outside the automobile), this background is clearly seen in black even from the interior of the vehicle, exactly as in Figure 1. The white pattern appears as a darker overprint than the background (darkening), creating a relief effect.

[0031] In Figure 3, we see, from the outside of the car (Side 1), the blue dots on a black background of Test No. 2 which can create a seamless effect with a bodywork that is also blue. Seen from the passenger compartment of the car (Figure 4), the same observations as for Figure 2 apply: a haptic texturing effect has been produced.

[0032] This is also the case for the blue triangles on a black background in Test No. 3 (Figures 5 and 6).

Claims

Claims 1. Use of a monolithic or laminated, single or multiple glazing, one face of a constituent glass sheet of which is coated with at least a first layer of enamel of a first color according to a pattern, then with a second layer of enamel of a second color different from the color(s) of the at least one first layer of enamel, the second layer of enamel covering flat at least in part the pattern of at least one first layer of enamel, to produce a haptic texturing effect.

2. Use according to claim 1, characterized in that the glass sheet is flat or curved, made of mineral glass of the float, soda-lime, aluminosilicate, borosilicate type, clear or tinted, possibly hardened, thermally tempered or chemically reinforced.

3. Use according to one of the preceding claims, characterized in that the glass sheet coated with the enamel layers is laminated by bonding to another glass sheet by means of an intermediate adhesive layer of polyvinyl butyral (PVB), polyurethane (PU), ethylene vinyl acetate (EVA), casting resin or ionomer, the face of the glass sheet coated with the enamel layers being oriented towards this intermediate adhesive layer.

4. Use according to one of the preceding claims, characterized in that the second layer of enamel is based on bismuth silicate, bismuth borosilicate or bismuth borate, or bismuth and zinc silicate, bismuth and zinc borosilicate or bismuth and zinc borate.

5. Method of manufacturing glazing for use according to one of the preceding claims, characterized in that it comprises the operations consisting of: - depositing on one side of a sheet of mineral glass a first layer of enamel precursor or several first layers of enamel precursor of different colors according to a pattern, - dry the first layer(s) of all enamel precursor one by one before depositing the next, and / or in groups of several of them, or all simultaneously, - deposit a second layer of enamel precursor of a color different from that(s) of the enamel(s) of the first layer(s), flat, at least partially covering the pattern of the first layer(s) of enamel, and - cook the enamels.

6. Method according to claim 5, characterized in that the wet thickness of the or each first layer of enamel precursor is between 20 and 28 pm and that of the second layer of enamel precursor between 20 and 28 pm or between 38 and 46 pm if the or a first layer of enamel precursor contains metallic or dichroic pigments.

7. Method according to claim 5, characterized in that the deposition of the layers of enamel precursors is carried out by printing techniques such as screen printing, in particular in a single pass for each layer, digital printing such as inkjet, roller transfer.

8. Method according to claim 5, characterized in that the drying is carried out between 140 and 180°C for 1 to 3 min, in particular by means of an infrared dryer.

9. Method according to claim 5, characterized in that the firing of the enamels is carried out between 590 and 690°C, in particular for 100 to 600 seconds for a thickness of the glass sheet of between 2.1 and 3.85 mm.

10. Method according to claim 5, characterized in that the mineral glass sheet is subjected to a treatment of bending, thermal toughening or chemical strengthening and / or lamination to another glass sheet, the face of the glass sheet coated with the enamel layers being in the latter case oriented towards an interlayer adhesive layer, treatment in which the firing of the enamels is integrated.

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