阅读说明：本技术 涂有矿物漆层和薄层堆叠体的玻璃片材 (Glass sheet coated with a mineral varnish layer and a stack of thin layers ) 是由 J·雅马尔 于 2020-02-20 设计创作，主要内容包括：本发明涉及一种包含玻璃片的材料,玻璃片的一个面包括第一区域和第二区域,只有第一区域涂有由包含颜料和碱性硅酸盐水溶液的水基漆组合物获得的不透明矿物漆层,所述矿物漆层和玻璃片的第二区域涂有包含至少一个导电薄层的薄层堆叠体。本发明还涉及包含这样的材料的层压玻璃板。(The invention relates to a material comprising glass flakes, one face of which comprises a first region and a second region, only the first region being coated with an opaque mineral paint layer obtained from a water-based paint composition comprising a pigment and an aqueous solution of an alkali silicate, the mineral paint layer and the second region of the glass flakes being coated with a stack of thin layers comprising at least one electrically conductive thin layer. The invention also relates to a laminated glass pane comprising such a material.)

1. A material comprising a glass sheet, one side of which comprises a first region and a second region, only the first region being coated with an opaque mineral paint layer obtained from a water based paint composition comprising a pigment and an aqueous solution of an alkali silicate, the mineral paint layer and the second region of the glass sheet being coated with a stack of thin layers comprising at least one electrically conductive thin layer.

2. The material as claimed in claim 1, wherein at least one thin electrically conductive layer is a metal layer, in particular a layer based on silver, or an electrically conductive transparent oxide.

3. A material as claimed in any one of the preceding claims, such that the opaque mineral paint layer is black, preferably with a brightness L measured in reflection on the glass side of less than 5.

4. A material as claimed in any one of the preceding claims, in which the first region constitutes from 2% to 25%, especially from 3% to 20%, of the area of the coated side.

5. The material as claimed in one of the preceding claims, such that in the mineral paint layer the content by weight of alkali silicate is from 7% to 60% and the total content by weight of pigment and mineral filler is from 20% to 90%.

6. A material as claimed in any preceding claim, such that the opaque mineral paint layer has been subjected to a pre-firing step at a temperature of at least 550 ℃ prior to deposition of the thin-film stack.

7. Laminated glazing, in particular for motor vehicle windscreens or sunroofs, comprising a material as claimed in one of the preceding claims adhesively bonded to an additional glass sheet via a laminating interlayer, such that the mineral lacquer layer and the stack of thin layers are directed towards the interlayer.

8. Laminated glass pane as claimed in the preceding claim, wherein the additional glass sheet is made of sodium aluminosilicate glass, which is preferably chemically strengthened, and has a thickness of 0.5 to 1.2 mm.

9. A laminated glass pane as claimed in claim 7, wherein the additional glass sheet is provided with an additional stack of thin layers, in particular a low-emissivity stack comprising a conductive transparent oxide, on the side opposite to the side facing the lamination interlayer.

10. A method of obtaining a material as claimed in one of claims 1 to 6, comprising the following steps:

-providing a glass sheet, one face of which comprises a first zone and a second zone, and then

-a step of depositing on the first region an aqueous-based paint composition comprising a pigment and an aqueous solution of an alkali silicate, and then

-a step of pre-firing at a temperature of at least 200 ℃ to obtain a mineral paint layer, followed by

-a step of depositing a stack of thin layers comprising at least one electrically conductive thin layer on the layer of mineral paint and on a second region of the glass sheet.

11. The method as claimed in the preceding claim, wherein the pre-firing step is carried out at a temperature of at least 550 ℃.

12. A method as claimed in claim 10 or 11, wherein the step of depositing the lacquer composition is performed by screen printing.

13. The method as claimed in one of claims 10 to 12, wherein the step of depositing the stack of thin layers is performed by cathode sputtering.

14. A method of obtaining a laminated glass sheet as claimed in one of claims 7 to 9 comprising the steps of:

-providing the material obtained according to the method of one of claims 10 to 13 and an additional glass sheet, then

-a step of bending, in particular simultaneously, said material and said additional glass sheet, then

-a step of laminating the material with the additional glass sheet via a lamination interlayer such that the mineral lacquer layer and the stack of thin layers are directed towards the interlayer.

15. The method as claimed in the preceding claim, wherein the step of cutting the material is performed before the step of bending.

A comparison of examples a and D shows that the presence of an enamel layer in contact with the thin-layer stack is detrimental to the conductivity properties of the stack after firing, since the sheet resistance is greatly increased, and the higher the firing temperature, the more so.

On the other hand, the use of a silicate lacquer layer (example B) makes it possible to maintain a favourable resistivity, at the same level as that obtained in the absence of a black layer (example D), but provided that the pre-firing is carried out at high temperature (example C). However, a low temperature pre-firing as in the case of example C is not detrimental when the electrically conductive properties in the area of the covering lacquer layer are not important, for example when the infrared radiation reflecting properties of the thin-layer stack are utilized.