Privacy film for automobile sunroof

Abstract

The utility model discloses a privacy film for an automobile skylight. The privacy film comprises a base material layer, a light pollution prevention layer and a low reflection layer. The base material layer is provided with a first surface and a second surface which are oppositely arranged, and the second surface is coated with optical cement and used for being pasted to an automobile skylight. And the light pollution prevention layer is coated on the first surface of the base material layer. The low-reflection layer is arranged on the side, away from the base material layer, of the light pollution prevention layer in a magnetron sputtering mode. When the included angle between the sight line of the human eyes and the normal line of the automobile sunroof ranges from 55 degrees to 70 degrees, the glossiness of the privacy film ranges from 15 GU to 35 GU. The value of distinctness of image is between 40 and 90. According to the privacy film for the automobile skylight, the definition and the brightness of a reflection picture on the automobile skylight can be reduced, and the privacy of a driver and passengers in an automobile is protected.

Description

Technical Field

[0001] The utility model belongs to the technical field of automotive films, and particularly relates to a privacy film for an automotive sunroof. Background Art

[0002] An automotive sunroof is a window installed on the roof of an automobile. It can be opened or tilted, providing better ventilation, lighting, and comfort for the driver and passengers. It not only allows fresh air to flow into the vehicle but also increases the brightness and sense of space inside the vehicle. Sunroofs are often made of highly reflective mirror glass. The light reflection on the surface of this kind of glass is very strong. And to increase the transmittance, manufacturers usually apply an anti-reflection film on the sunroof using either the dry method or the wet method. In this way, when the driver in the front row and the passengers in the back row use their mobile phones or handle their private affairs, especially at night, the content of the mobile phone screen and the actions of the passengers and the driver will be reflected on the sunroof glass. When the driver in the front row and the passengers in the back row look up at the roof, they can clearly see the content of the other party's mobile phone screen and the other party's actions, resulting in both parties being unable to maintain privacy inside the vehicle.

[0003] To solve this problem, some automotive manufacturers have begun to adopt the world's leading privacy film technology to enhance the privacy and passenger safety of the vehicle windows. For example, electrochromic glass controls the light transmittance by adjusting the voltage, which can effectively block ultraviolet rays and heat, improving the comfort inside the vehicle; at the same time, it can reduce the load on the air conditioning system, saving energy and protecting the environment; in addition, it can also lower the indoor temperature and reduce the damage to the items inside the vehicle caused by direct sunlight. However, the cost of electrochromic glass is relatively high, and the installation and maintenance costs are also high; in addition, performance degradation or damage may occur during long-term use, requiring maintenance and replacement.

[0004] The information disclosed in this background art section is only intended to enhance the overall understanding of the utility model and should not be regarded as an admission or any form of suggestion that this information constitutes prior art already known to those of ordinary skill in the art. Summary of the Utility Model

[0005] The purpose of the utility model is to provide a privacy film for an automotive sunroof, which can reduce the clarity and brightness of the reflected image on the automotive sunroof and protect the privacy of the driver and passengers inside the vehicle.

[0006] To achieve the above object, a specific embodiment of the present utility model provides a privacy film for an automotive sunroof, which includes: a substrate layer, an anti-light pollution layer, and a low-reflection layer. The substrate layer has a first surface and a second surface disposed opposite to each other, and the second surface is coated with an optical adhesive for pasting with the automotive sunroof. The anti-light pollution layer is coated on the first surface of the substrate layer. The low-reflection layer is magnetron sputtered on the side of the anti-light pollution layer away from the substrate layer. Wherein, when the included angle between the human eye line of sight and the normal line of the automotive sunroof is between 55° and 70°, the glossiness of the privacy film is between 15GU and 35GU; the DOI value is between 40 and 90.

[0007] In one or more embodiments of the present utility model, the thickness of the anti-light pollution layer is between 3μm and 6μm.

[0008] In one or more embodiments of the present utility model, the haze of the anti-light pollution layer is between 4% and 30%.

[0009] In one or more embodiments of the present utility model, the anti-light pollution layer is selected from one of an organic particle resin layer and an inorganic particle resin layer.

[0010] In one or more embodiments of the present utility model, the thickness of the low-reflection layer is between 240nm and 250nm.

[0011] In one or more embodiments of the present utility model, it further includes:

[0012] An anti-fouling layer, which is coated on the surface of the low-reflection layer away from the anti-light pollution layer.

[0013] In one or more embodiments of the present utility model, the thickness of the anti-fouling layer is between 10nm and 20nm.

[0014] In one or more embodiments of the present utility model, the substrate layer is selected from one of a PET layer, a TAC layer, and a PC layer.

[0015] In one or more embodiments of the present utility model, the thickness of the substrate layer is between 50μm and 125μm.

[0016] In one or more embodiments of the present utility model, the low-reflection layer includes a plurality of high-refractive-index layers and a plurality of low-refractive-index layers that are alternately stacked, and the refractive index of the low-refractive-index layer is less than that of the high-refractive-index layer.

[0017] Compared with the prior art, the privacy film for automotive skylights of the present utility model can reduce the clarity and brightness of the reflected images on the automotive skylight by providing an anti-light pollution layer and a low-reflection layer, thereby enhancing the privacy of the driver and passengers inside the vehicle. While ensuring privacy, the privacy film also takes into account the light transmittance to guarantee the clarity of the privacy film. Additionally, the privacy film is provided with an anti-fouling layer to further improve its anti-fouling property. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings described below are only some embodiments recorded in the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0019] Figure 1 Schematic diagram of the privacy film for automotive skylights without an anti-fouling layer in an embodiment of the present utility model;

[0020] Figure 2 Schematic diagram of the privacy film for automotive skylights with an anti-fouling layer in an embodiment of the present utility model.

[0021] Main reference numeral description:

[0022] 1 - Substrate layer, 2 - Anti-light pollution layer, 3 - Low-reflection layer, 4 - Anti-fouling layer. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] In order to enable those skilled in the art of this technology to better understand the technical solutions in the present utility model, the following will clearly and completely describe the technical solutions in the embodiments of the present utility model in conjunction with the drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present utility model.

[0024] Automobile sunroofs can be opened or tilted, providing better ventilation, lighting, and comfort for drivers and passengers. Automobile sunroofs can not only let fresh air flow into the vehicle but also increase the brightness and sense of space inside the vehicle. However, sunroofs are often made of highly reflective mirror glass with an anti-reflection film on the surface. In this way, when the driver in the front row and the passengers in the back row use their mobile phones or handle their personal affairs, especially at night, the content and actions of the mobile phone screens will be reflected on the sunroof glass. When the driver in the front row and the passengers in the back row look up at the roof of the car, they can clearly see the content of each other's mobile phone screens and each other's actions, resulting in both parties being unable to maintain privacy in the vehicle. At this time, the angle between the human eye's line of sight and the normal line of the automobile sunroof usually ranges between 55° - 70°, which is also the most common angle for the human eye to observe, and this angle range applies to most automobiles.

[0025] As Figure 1 shown, a privacy film for an automobile sunroof in an embodiment of the present utility model includes a substrate layer 1, an anti-light pollution layer 2, and a low-reflection layer 3. The substrate layer 1 has a first surface and a second surface arranged opposite to each other, and the second surface can be coated with an optical adhesive for pasting with the automobile sunroof. The anti-light pollution layer 2 is coated on the first surface of the substrate layer 1. The low-reflection layer 3 is magnetron sputtered on the side of the anti-light pollution layer 2 away from the substrate layer 1. Among them, when the angle between the human eye's line of sight and the normal line of the automobile sunroof is between 55° - 70°, the anti-light pollution layer 2 and the low-reflection layer 3 make the glossiness of the privacy film between 15GU - 35GU; the DOI value is between 40 - 90.

[0026] In the above embodiment, the privacy film for the automobile sunroof, by combining the anti-light pollution layer 2 and the low-reflection layer 3, makes the mobile phone content and respective actions of the driver and passengers in the vehicle not observable by each other through the reflection of the automobile sunroof, or even if observable, the reflected content or actions on the sunroof are extremely blurred. Especially when the angle between the human eye's line of sight and the normal line of the low-reflection layer 3 is between 55° - 70°, the mobile phone content and respective actions of the driver and passengers in the vehicle are not easily or extremely difficult to observe. The setting of the low-reflection layer 3 reduces the brightness of the content reflected on the sunroof and the privacy film. The setting of the anti-light pollution layer 2 can increase the scattering of the privacy film, making the content reflected on the sunroof and the privacy film become blurred.

[0027] In one embodiment, the anti-light pollution layer 2 is coated on the substrate layer 1 through a precision wet coating process. Considering that an overly thick anti-light pollution layer 2 may affect the haze and increase the manufacturing cost, the thickness of the anti-light pollution layer 2 is controlled between 3 μm and 6 μm. Additionally, the haze of the anti-light pollution layer 2 is between 4% and 30%. When the haze is too high, although the transmittance and imaging clarity of the privacy film can still meet the requirements, after it is pasted on the sunroof, it will affect the user's visual effect of the scenery outside the window. If the haze is too low, the phone content will be clearly reflected on the sunroof and the privacy film.

[0028] Furthermore, in order to effectively control the haze of the anti-light pollution layer 2, the anti-light pollution layer 2 is selected from one of an organic particle resin layer and an inorganic particle resin layer. Among them, the organic particles of the organic particle resin layer can be one or more of PMMA, PE, and PC. The inorganic particles of the inorganic particle resin layer can be one or more of silicon oxide, aluminum oxide, and titanium oxide.

[0029] The low-reflection layer 3 is magnetron sputtered on the anti-light pollution layer 2. In order to improve the low-reflection effect of the privacy film and reduce the brightness of the content reflected by the privacy film, the thickness of the low-reflection layer 3 is controlled between 240 nm and 250 nm. Among them, the low-reflection layer 3 can be composed of a plurality of high-refractive-index layers and a plurality of low-refractive-index layers arranged in an alternating laminated manner, and the refractive index of the low-refractive-index layer is less than that of the high-refractive-index layer. Specifically, the high-refractive-index layer can be a Nb2O5 layer, and the low-refractive-index layer can be a SiO2 layer.

[0030] To improve the stain resistance of the privacy film, as Figure 2 shown, the privacy film is further provided with an anti-stain layer 4. The anti-stain layer 4 is coated on the surface of the low-reflection layer 3 away from the anti-light pollution layer 2, and the thickness of the anti-stain layer 4 is between 10 nm and 20 nm.

[0031] In one embodiment, the substrate layer 1 is selected from one of a PET layer, a TAC layer, and a PC layer, and the thickness of the substrate layer 1 is between 50 μm and 125 μm.

[0032] The present utility model will be further elaborated below in conjunction with specific embodiments and comparative examples.

[0033] Example 1

[0034] Substrate layer 1: TAC substrate layer, with a thickness of 60 μm.

[0035] Anti-light pollution layer 2: Organic particle resin layer, the ratio of resin to organic particles is 9:5, and the thickness is 4 μm.

[0036] Low-reflection layer 3: A stacked structure of Nb2O5 layer - SiO2 layer - Nb2O5 layer - SiO2 layer. The thickness of the first Nb2O5 layer is 17 nm, the thickness of the second SiO2 layer is 26 nm, the thickness of the third Nb2O5 layer is 115 nm, and the thickness of the fourth SiO2 layer is 90 nm.

[0037] Antifouling layer 4: Thickness 10 nm.

[0038] Example 2

[0039] Substrate layer 1: TAC substrate layer, thickness 60 μm.

[0040] Anti-glare pollution layer 2: Inorganic particle resin layer, the ratio of resin to inorganic particles is 9:6, thickness 4 μm.

[0041] Low-reflection layer 3: A stacked structure of Nb2O5 layer - SiO2 layer - Nb2O5 layer - SiO2 layer. The thickness of the first Nb2O5 layer is 17 nm, the thickness of the second SiO2 layer is 26 nm, the thickness of the third Nb2O5 layer is 115 nm, and the thickness of the fourth SiO2 layer is 90 nm.

[0042] Antifouling layer 4: Thickness 10 nm.

[0043] Example 3

[0044] Substrate layer 1: TAC substrate layer, thickness 60 μm.

[0045] Anti-glare pollution layer 2: Organic particle resin layer, the ratio of resin to organic particles is 1:1, thickness 4 μm.

[0046] Low-reflection layer 3: A stacked structure of Nb2O5 layer - SiO2 layer - Nb2O5 layer - SiO2 layer. The thickness of the first Nb2O5 layer is 17 nm, the thickness of the second SiO2 layer is 26 nm, the thickness of the third Nb2O5 layer is 115 nm, and the thickness of the fourth SiO2 layer is 90 nm.

[0047] Antifouling layer 4: Thickness 10 nm.

[0048] Comparative example 1

[0049] Substrate layer: TAC substrate layer, thickness 60 μm.

[0050] Anti-glare pollution layer: Organic particle resin layer, the ratio of resin to organic particles is 9:5, thickness 4 μm.

[0051] Comparative example 2

[0052] Substrate layer: TAC substrate layer, thickness 60 μm.

[0053] Anti-glare layer: an inorganic particle resin layer, with the ratio of resin to organic particles being 9:6 and a thickness of 4 μm.

[0054] Comparative Example 3

[0055] Substrate layer: a TAC substrate layer with a thickness of 60 μm.

[0056] Anti-glare layer: an organic particle resin layer, with the ratio of resin to organic particles being 1:1, a thickness of 4 μm, and a haze of 25%.

[0057] Comparative Example 4

[0058] Substrate layer: a TAC substrate layer with a thickness of 60 μm.

[0059] Hardening layer: an acrylic resin layer with a thickness of 4 μm.

[0060] Low-reflection layer; with a thickness of 248 nm.

[0061] Anti-fouling layer: with a thickness of 10 nm.

[0062] Comparative Example 5

[0063] Substrate layer: a TAC substrate layer with a thickness of 60 μm.

[0064] Anti-glare layer: an organic particle resin layer, with the ratio of resin to organic particles being 9:11 and a thickness of 4 μm.

[0065] Low-reflection layer: a stacked structure of Nb2O5 layer - SiO2 layer - Nb2O5 layer - SiO2 layer. Among them, the thickness of the first Nb2O5 layer is 17 nm, the thickness of the second SiO2 layer is 26 nm, the thickness of the third Nb2O5 layer is 115 nm, and the thickness of the fourth SiO2 layer is 90 nm.

[0066] Anti-fouling layer: with a thickness of 10 nm.

[0067] Attach the privacy films of Examples 1 - 3 and Comparative Examples 1 - 5 to the blackboard, and test the optical data using a haze meter and a gloss meter. The test standard of the haze meter is ASTM D1003, and the test standard of the gloss meter is ISO 2813. The test results are shown in Table 1 below.

[0068] Table 1 Optical test results of Examples 1 - 3 and Comparative Examples 1 - 5

[0069]

[0070]

[0071] In Table 1, Gloss is used to represent the percentage of the amount of reflected light. Distinctness of Image (DOI) is used to represent the clarity of the reflected image on the surface of the privacy film. The DOI value is usually between 0 and 100. The higher the value, the clearer and sharper the reflected light on the material surface, the clearer the image, and the better the visual effect. It can be seen from the data in Table 1 that while not affecting the transmittance (T.T) of the privacy film, as the haze of the privacy film increases, the glossiness and DOI value obtained by illuminating with a 60° light source of the glossmeter decrease, which means the imaging effect of the privacy film is worse. Compared with Comparative Examples 1-3, the privacy films of Examples 1-3 have a low-reflection layer and an anti-fouling layer, with further reduced glossiness and DOI values and further increased transmittance. In Comparative Example 4, the anti-light pollution layer is removed, acrylic resin is used as the hardening coating, and an anti-reflection layer is magnetron sputtered on it. Although the haze is small and the transmittance is high, after it is pasted on the glass, the reflection is still strong in a darker background, and the user can still clearly see the content on the mobile phone. In Comparative Example 5, when the haze rises to 50%, the transmittance, DOI and other data of the privacy film meet the requirements, but when it is pasted on the glass, it is found that it will affect the user's view of the outside window.

[0072] In summary, for the privacy film for automotive sunroofs of the present utility model, by providing the anti-light pollution layer 2 and the low-reflection layer 3, the clarity and brightness of the reflected image on the automotive sunroof can be reduced, thereby improving the privacy of the driver and passengers in the vehicle. While ensuring privacy, the privacy film can also take into account the light transmittance and ensure the clarity of the privacy film. In addition, the privacy film is provided with an anti-fouling layer 4, which can further improve the anti-fouling property of the privacy film.

[0073] For those skilled in the art, it is obvious that the present utility model is not limited to the details of the above-described exemplary embodiments, and without departing from the spirit or basic characteristics of the present utility model, the present utility model can be implemented in other specific forms. Therefore, in any aspect, the embodiments should be regarded as exemplary and non-limiting. The scope of the present utility model is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present utility model. Any reference signs in the claims should not be regarded as limiting the claimed rights.

[0074] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A privacy film for an automotive sunroof, characterized in that, Comprising: A substrate layer having a first surface and a second surface disposed opposite to each other, wherein the second surface is coated with an optical adhesive for pasting with an automotive skylight; An anti-light pollution layer coated on the first surface of the substrate layer; And A low-reflection layer magnetron sputtered on a side of the anti-light pollution layer away from the substrate layer; Wherein, when the included angle between the line of sight of the human eye and the normal line of the automotive skylight is between 55° - 70°, the glossiness of the privacy film is between 15GU - 35GU; the DOI value is between 40 - 90.

2. The privacy film for automotive skylights according to claim 1, characterized in that, The thickness of the anti-light pollution layer is between 3μm - 6μm.

3. The privacy film for automotive skylights according to claim 1, characterized in that, The haze of the anti-light pollution layer is between 4% - 30%.

4. The privacy film for an automotive sunroof according to claim 1, wherein The anti-light pollution layer is selected from one of an organic particle resin layer and an inorganic particle resin layer.

5. The privacy film for an automotive sunroof according to claim 1, wherein, The thickness of the low-reflection layer is between 240nm - 250nm.

6. The privacy film for automotive sunroof according to claim 1, characterized in that Further comprising: An anti-fouling layer coated on a surface of the low-reflection layer away from the anti-light pollution layer.

7. The privacy film for an automobile sunroof according to claim 6, characterized in that, The thickness of the anti-fouling layer is between 10nm - 20nm.

8. The privacy film for an automotive sunroof according to claim 7, characterized in that, The substrate layer is selected from one of a PET layer, a TAC layer, and a PC layer.

9. The privacy film for an automotive sunroof according to claim 1, characterized in that, The thickness of the substrate layer is between 50μm - 125μm.

10. The privacy film for a vehicle sunroof according to claim 1, characterized in that, The low-reflection layer includes a plurality of high-refractive-index layers and a plurality of low-refractive-index layers stacked alternately, and the refractive index of the low-refractive-index layer is less than that of the high-refractive-index layer.

Images