A vehicle window and a production method for vehicle window

Abstract

The invention relates to a vehicle window comprising a transparent glass substrate (10). The vehicle window contains a coating layer (20) provided on the glass substrate (10) by a screen-printing method.

Description

[0001] A VEHICLE WINDOW AND A PRODUCTION METHOD FOR VEHICLE WINDOW

[0002] TECHNICAL FIELD

[0003] The present invention relates to a window used in a vehicle with a coating designed to reflect infrared radiation.

[0004] BACKGROUND OF THE ART

[0005] Coating layers are used on vehicle windows to block ultraviolet or infrared reflections. Silver- containing coatings cannot be used on the outer, exposed surfaces of vehicle window because they oxidize due to the oxygen present in the air. Their use is limited to composite sheets consisting of two glass plates bonded together with a thermoplastic interlayer. The coatings must be arranged on the inner surface of the glass plates facing the interlayer.

[0006] Additionally, to encapsulate the coating within the laminated sheet, which is protected against corrosion, a peripheral edge area of the coating must be removed. Since an uncoated edge area leads to a visible side edge of the coating, which is not aesthetically appealing, the use of coatings is limited to composite sheets equipped with an opaque peripheral edge area where the side edge of the coating can be hidden. Therefore, the use of coatings is largely limited to windshields and roof panels, which are typically designed as composite panels and often have an opaque edge area made of printed and baked black enamel.

[0007] WO2022223179A1 relates to a vehicle window with infrared reflection. Publication involves a vehicle window comprising at least one transparent glass panel and an IR-reflective coating on one surface of the glass panel, where the IR-reflective coating includes n metallic layers and (n+1 ) dielectric layers, where the layers are formed as dielectric layers or layer arrays, and the layers and metallic layers are alternately arranged such that each metallic layer is disposed between two layer arrays, where n is a natural number greater than or equal to 1 , where each metallic layer is formed as a discontinuous layer of metal nanocrystals. It has areas filled with metal nanocrystals and areas not filled with nanocrystals. The topmost layer array has an anti reflective dielectric layer with a refractive index of at most 1.7. SUMMARY OF THE INVENTION

[0008] The object of the invention is related to the easy production of vehicle windows with various coated variations.

[0009] In order to achieve the above objective, the invention is a vehicle window is comprising a transparent glass substrate. The vehicle window contains a coating layer provided on the glass substrate by the screen-printing method. Thus, when screen printing is applied to the glass substrate, a highly durable coating layer is obtained. The special liquids or UV lights used in this method ensure that the coating layer adheres durably to the glass substrate. As a result, the coating layer is resistant to long-term use and wear. Additionally, with the screen-printing method, transparency control is provided. The application of liquids to the glass in different ways allows for different levels of transparency.

[0010] In a preferred embodiment of the invention, the coating layer is provided on an outer wall of the glass substrate. Thus, a structure is obtained in the vehicle window that reflects or transmits light coming from the external environment. In an alternative embodiment, the coating layer can also be provided on an inner wall of the glass substrate.

[0011] In a preferred embodiment of the invention, the thickness of the coating layer ranges from 5 to 25 microns. This allows for the creation of a transparent vehicle window structure.

[0012] In a preferred embodiment of the invention, the thickness of the coating layer ranges from 10 to 20 microns. This allows for the creation of a transparent vehicle window structure.

[0013] In a preferred embodiment of the invention, the thickness of the glass substrate ranges from 0.3 mm to 2.7 mm. This provides a vehicle window structure with high structural strength and long product life.

[0014] In a preferred embodiment of the invention, the thickness of the glass substrate ranges from 0.7 mm to 2.2 mm. This provides a vehicle window structure with high structural strength and long product life.

[0015] In a preferred embodiment of the invention, the light transmission value of the coating layer ranges from 10% to 90%. While maintaining the light transmission value, the UV and IR transmission values are kept low by reflection, reducing the temperature felt on human skin. At the same time, the interior temperature of a vehicle parked under the sun is kept suitable for driving.

[0016] In a preferred embodiment of the invention, the infrared reflection value of the coating layer ranges from 10% to 70%. This prevents harmful rays from posing a threat to the driver or passengers.

[0017] In a preferred application of the invention, the coating layer is provided on the outer wall of the glass substrate by the screen-printing method. Thus, a low-cost and fast production method is used.

[0018] In a preferred application of the invention, a conductive and transparent liquid is applied along the coating layer for the screen-printing process on the glass substrate. Thus, a transparent vehicle window structure is obtained, and a coating layer with a long product life is also obtained.

[0019] In a preferred application of the invention, the liquid applied to the glass substrate is cured using ultraviolet or infrared rays. Thus, the liquid is fixed on the glass substrate, providing a compact vehicle window structure.

[0020] BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic top view of the vehicle window according to the invention.

[0022] Figure 2 is a schematic side view of the vehicle window according to the invention.

[0023] DETAILED DESCRIPTION OF THE INVENTION

[0024] In this detailed description, the subject matter is explained with references to examples to better illustrate the invention without any limitation.

[0025] Figure 1 schematically shows the vehicle window from the top according to the invention. The vehicle window comprises a glass substrate (10) and the glass substrate (10) consists of multiple sub-layers. The glass substrate has a thickness of 0.7 to 2.2 mm. In some example arrangements, the glass substrate (10) uses a coating layer (20) to block at least some amount of infrared (IR) radiation, such as a solar management coating (e.g., low-E coating). In some example arrangements, the coating layer (20) may have an emissivity (En) not exceeding 0.20 and / or a sheet resistance (Rs) not exceeding 8 ohms / square. The coating layer (20) is placed on an outer wall (12) of the glass substrate (10) within a thickness range of 10 to 20 microns. In this thickness range, a transparent structure is obtained against light transmission. The vehicle window preferably has at least about 50%, more preferably at least about 60%, and even more preferably at least about 65% or at least about 70% visible transmission. Additionally, the UV reflection of the coating layer (20) is at least 38%, more preferably at least 40%, more preferably at least 55%, even more preferably at least 60%, and possibly at least 65%. Furthermore, a coating layer can have a visible reflection of less than about 20%, more preferably less than about 15%, and most preferably less than about 10%. The infrared reflection values of the coating layer (20) range from 10% to 70%.

[0026] Figure 2 schematically shows the vehicle window from the side according to the invention. An inner wall (14) is provided opposite the coating layer (20) on the outer wall (12) of the glass substrate (10). An outer glass substrate (30) is provided spaced apart from the outer wall (12) of the glass substrate (10). The inner wall (14) of the glass substrate (10) represents the part of the laminated glass facing the interior of the vehicle. The outer wall (32) of the second glass substrate (30) represents the part facing the external environment. The outer wall (12) of the glass substrate (10) and the inner wall (32) of the second glass substrate (30) face each other and are bonded together with a thermoplastic interlayer (40). The interlayer is formed with at least one layer of thermoplastic material. The interlayer can consist of this single thermoplastic material layer, such as a single polymer film or a bulk resin layer. However, the interlayer can also contain multiple layers of thermoplastic material and can be formed from numerous polymer films placed flat on top of each other. At least one polymer film preferably includes ethylene vinyl acetate (EVA), polyvinyl butyral (PVB), or polyurethane (PU) or their mixtures or copolymers or derivatives, particularly preferably PVB. The thickness of the polymer film is preferably in the range of 0.2 mm to 2 mm, more preferably in the range of 0.3 mm to 1 mm. The PVB in the interlayer (40) can be preferred as a UV reflective blocking coating to reflect ultraviolet radiation. In certain example arrangements, the UV reflective property can block at least 38% of UV radiation in the range of 350-440 nm, more preferably at least 40%, more preferably at least 55%, most preferably at least 60%, and possibly at least 65%. The use of such polymer film here increases the performance of the glass substrate (10) by enhancing UV reflection beyond the normal limits of uncoated plate glass in the spectrum range of 300-440 nm. In the production method of the vehicle window according to the invention, a transparent and conductive liquid is spread along the coating layer (20) on the outer wall (12) of the glass substrate (10). The liquid is cured using ultraviolet and / or infrared rays, making it suitable for a screen-printing process. By applying the liquid, a coating layer (20) is placed on the glass substrate (10) through a screen-printing process, obtaining a vehicle window structure with desired properties.

[0027] REFERENCE NUMBERS 10 Glass Substrate

[0028] 12 Outer Wall

[0029] 14 Inner Wall

[0030] 20 Coating Layer

[0031] 30 Outer Glass Substrate 32 Inner Wall

[0032] 40 Interlayer

Claims

CLAIMS1. A vehicle window comprising a transparent glass substrate (10) characterized by a coating layer (20) is provided on the glass substrate (10) by a screen-printing method.

2. A vehicle window according to claim 1 , wherein the coating layer (20) is provided on an outer wall (12) of the glass substrate (10).

3. A vehicle window according to claim 2, wherein the thickness of the coating layer (20) ranges from 5 to 25 microns.

4. A vehicle window according to claims 2-3, wherein the thickness of the coating layer(20) ranges from 10 to 20 microns.

5. A vehicle window according to any of the preceding claims, wherein the thickness of the glass substrate (10) ranges from 0.3 mm to 2.7 mm.

6. A vehicle window according to claim 5, wherein the thickness of the glass substrate(10) ranges from 0.7 mm to 2.2 mm.

7. A vehicle window according to any of the preceding claims, wherein the light transmission value of the coating layer (20) ranges from 10% to 90%.

8. A vehicle window according to any of the preceding claims, wherein the infrared reflection value of the coating layer (20) ranges from 10% to 70%.

9. A production method for a vehicle window according to any of the preceding claims, comprising the step of providing a coating layer (20) by the screen-printing method on an outer wall (12) of the glass substrate (10).

10. A production method according to claim 9, comprising the step of applying a conductive and transparent liquid along the coating layer (20) for the screenprinting process on the glass substrate (10).

11. A production method according to claim 10, comprising the step of curing the liquid applied to the glass substrate (10) using ultraviolet or infrared rays.

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