Self-cleaning and anti-fog automobile glass film

Abstract

The utility model discloses an automobile glass film, and particularly relates to a self-cleaning and anti-fog automobile glass film, which has a layered structure comprising a release film layer, a pressure-sensitive adhesive layer, a PET (polyethylene terephthalate) base material layer and a polyurethane-SiO2 composite super-hydrophilic transparent coating which are compounded in sequence. According to the utility model, the technical problem that the surface of the automobile glass film has self-cleaning and anti-fogging performance by spraying the anti-fogging coating is solved. The automobile glass film is good in light transmission, the average transmittance of the automobile glass film in the visible light range (350-800 nm) can reach 85.50%, the wettability of the surface of the coating is super-hydrophilic, and the surface contact angle is only 5.5 degrees, so that the automobile glass film has good anti-fog and self-cleaning performance. The coating on the surface of the automobile glass film can bear the pressure intensity of about 26 kPa to the maximum extent, and has certain wear resistance. The surface coating of the automobile glass film has certain weather resistance, and the surface appearance and the self-cleaning and anti-fog effects of the automobile glass film cannot change along with time.

Description

TECHNICAL FIELD

[0001] The utility model relates to a kind of automobile glass films, in particular to a kind of self-cleaning, anti-fog automobile glass film. BACKGROUND

[0002] Automobile glass can realize the effects of anti-ultraviolet and scratch resistance by attaching glass film, and also can stick glass fragments together to prevent the fragments from splashing and hurting the owner when an accident occurs.

[0003] Fogging, also known as fogging, is more correctly called fogging, which refers to the phenomenon of condensation into tiny dew drops on the surface of glass or transparent plastic under high humidity. Because of the dense dew drops, the surface of these transparent materials becomes white, blurred and opaque. Therefore, in recent years, anti-fogging processing technology has gradually attracted attention.

[0004] The current main methods for anti-fogging of automobile glass film are electric heating and the use of anti-fogging paint. The former has good effect but high cost, so the research is mainly focused on anti-fogging paint.

[0005] For example: Cai Anjiang, Yan Xuerui, et al. proposed the preparation and characterization of self-cleaning, anti-fogging polyurethane-SiO2 composite super-hydrophilic transparent coating (Acta Materiae Compositae Sinica, Vol. 37, No. 1, January 2020). The abstract records that glass curtain walls have the disadvantages of difficult cleaning and easy fogging, increasing the cost of wall maintenance. With water-based polyurethane (PU), hydrophilic nano-SiO2, tetraethyl orthosilicate (TEOS) and ethanol as basic raw materials, PU-SiO2 coating solution is prepared by spraying process, and PU-SiO2 transparent coating with good wear resistance and anti-fogging is obtained after normal temperature curing. The surface morphology of PU-SiO2 coating is characterized by SEM, and the cause of surface wettability is explored by comparison experiment, and the principle of PU-SiO2 coating with super-hydrophilic property is analyzed. The results of wear resistance and anti-fogging test show that PU-SiO2 coating can withstand a pressure of about 26kPa and has good anti-fogging property. The results of UV-visible spectrophotometer test show that PU-SiO2 coating has good transparency. Outdoor placement experiment shows that PU-SiO2 coating has good weather resistance. This method solves the problems of complex process and environmental protection, and can be directly used for the surface of existing building glass curtain wall.

[0006] Therefore, the applicant proposes the utility model. SUMMARY

[0007] The utility model aims at solving the above-mentioned problems of the prior art and provides a kind of self-cleaning, anti-fog automobile glass film.

[0008] In order to achieve the above object, the utility model discloses a kind of self-cleaning, anti-fog automobile glass film, its laminar structure includes sequentially complex release film layer, pressure sensitive adhesive layer, PET substrate layer and polyurethane-SiO2 Composite superhydrophilic transparent coating (PU-SiO2 coating) in succession.

[0009] The SiO2 particles in the PU-SiO2 coating on the surface of the automobile glass film of the utility model are hydrophilic particles, which cause the wettability of the coating surface to change to hydrophilic. Under the combined action of SiO2 and the hydrolysis product of tetraethyl orthosilicate (TEOS), a three-dimensional fractal structure with nano-pores is formed, which makes the wettability of the surface of the automobile glass film coated with PU-SiO2 coating superhydrophilic. Since the superhydrophilic surface has good wettability, the force acting on the water droplets is greater than the surface tension of the water droplets, which causes the water droplets to spread evenly on the surface of the automobile glass film, i.e. the water droplets formed by condensation will spread on the surface of the PU-SiO2 superhydrophilic coating to form a water film, thereby eliminating light scattering. In addition to achieving the anti-fog effect, the utility model also enables the pollutants to automatically fall off under the action of external forces such as wind or gravity to achieve the self-cleaning effect. That is, the PU-SiO2 coating on the surface of the automobile glass film has good anti-fog and self-cleaning properties.

[0010] In addition, the three-dimensional fractal pore structure with nano-pores found in the PU-SiO2 coating on the surface is not only conducive to the change of the wettability of the surface of the automobile glass film from hydrophilic to superhydrophilic (the main reason for changing the wettability of the surface of the automobile glass film), but also conducive to the improvement of the light transmission of the coating.

[0011] As a preferred embodiment, the thickness of the PU-SiO2 composite superhydrophilic transparent coating in the laminar structure of the automobile glass film is preferably 5 μm to 12 μm.

[0012] As a preferred embodiment, the thickness of the PET substrate layer in the laminar structure of the automobile glass film is preferably 50 μm to 150 μm, and further preferably 75 μm to 125 μm.

[0013] As a preferred embodiment, the material of the pressure sensitive adhesive layer in the laminar structure of the automobile glass film is preferably transparent acrylic pressure sensitive adhesive, the visible light transmittance is preferably more than 90%, and the thickness is preferably 20 μm to 50 μm.

[0014] As a preferred embodiment, the release film layer in the laminar structure of the automobile glass film is preferably a PET release film, and more preferably a transparent PET release film. The haze is preferably less than 1.5%, the visible light transmittance is preferably more than 90%, the release force is preferably less than 20 g / inch, and the thickness is preferably 23 μm to 50 μm.

[0015] Compared with the prior art, the self-cleaning and anti-fog automobile glass film has the following technical effects:

[0016] The automobile glass film has good light transmittance, the average transmittance in the visible light range (350nm-800nm) can reach 85.50%, and the wettability of the coating surface is super-hydrophilic, and the surface contact angle is only 5.5°, so that the automobile glass film has good anti-fog and self-cleaning performance.

[0017] The surface coating of the automobile glass film can withstand a pressure of about 26kPa, and has certain wear resistance.

[0018] The surface coating of the automobile glass film has certain weather resistance, and the surface morphology and the self-cleaning and anti-fog effect thereof will not change with time. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 It is a schematic diagram of a layered structure of a self-cleaning and anti-fog automobile glass film.

[0020] In the figure: transparent PET release film layer 1, transparent acrylic pressure sensitive adhesive layer 2, PET substrate layer 3, polyurethane-SiO2 composite super-hydrophilic transparent coating 4. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art belong to the scope of protection of the present application. Embodiment 1

[0022] As shown in Figure 1 As an embodiment of the present application, the self-cleaning and anti-fog automobile glass film provided in the embodiment includes the following layered structure which is compounded in sequence: a transparent PET release film layer 1 (Wanrun Optoelectronics, C05-T1) with a thickness of 23μm, a transparent acrylic pressure sensitive adhesive layer 2 (Henkel, Loctite 8087) with a thickness of 20μm, a PET substrate layer 3 (Yihua Toray UV34) with a thickness of 50μm, and a polyurethane-SiO2 composite super-hydrophilic transparent coating 4 with a thickness of 5μm.

[0023] In addition, the embodiment also provides a preparation method of the above-mentioned self-cleaning and anti-fog automobile glass film, which has the following steps:

[0024] Step one, preparation of polyurethane-SiO2 composite super-hydrophilic transparent coating solution

[0025] Take 5g of water-based polyurethane (PU, Aldrin Reagent (Shanghai) Co., Ltd.), add 8mL of deionized water and 12mL of anhydrous ethanol (analytical pure, Tianjin Tianli Chemical Reagent Co., Ltd.), and mix into a mixed solution in a sealed container. Use a magnetic stirrer (524G magnetic stirrer, Shanghai Sile Instrument Co., Ltd.) to stir for 30 min to form a uniform dispersion. Take 0.1mL of tetraethyl orthosilicate (TEOS, analytical pure, Tianjin Tianli Chemical Reagent Co., Ltd.) and 0.05mL of hydrochloric acid (analytical pure, Xi'an Meijiu Trading Co., Ltd.), and continue to stir for 30 min. Continue to add 0.1g of SiO2 particles (diameter 15nm, hydrophilic, Shanghai Maklin Biotechnology Co., Ltd.), and continue to stir using a magnetic stirrer for 6h until the stirring is uniform, to obtain a polyurethane-SiO2 composite super-hydrophilic transparent coating solution.

[0026] Step two, coating and curing of pressure-sensitive adhesive solution

[0027] Coat the transparent acrylic pressure-sensitive adhesive solution (Henkel, Loctite 8087) on the surface of a transparent PET release film (Wanrun Optoelectronics, C05-T1) with a thickness of 23μm, dry at 110℃ for 2min, to form a pressure-sensitive adhesive layer with a dry adhesive thickness of 20μm, and then cover the pressure-sensitive adhesive layer on the surface of a PET substrate (Yuhua Toray UV34) with a thickness of 50μm.

[0028] Step three, spraying and curing of polyurethane-SiO2 composite super-hydrophilic transparent coating solution

[0029] Add the coating solution prepared in step one to a spray gun (W71 spray gun, Anest Iwata Industrial Machinery Co., Ltd.), and spray at a distance of 20cm from the PET substrate, with a spraying time of 4s. Then place it in a room temperature curing room for 24h.

[0030] Step four, place the semi-finished product in step three in a 50℃ curing room for 72h, to obtain a self-cleaning, anti-fog automotive glass film. Example 2:

[0031] As a second embodiment of the utility model, the self-cleaning, anti-fog automotive glass film provided in this embodiment has the same layered structure and preparation process as the aforementioned example 1.

[0032] However, the thickness of the polyurethane-SiO2 composite super-hydrophilic transparent coating in this embodiment is 8 μm; the thickness of the PET substrate (Toray, Lumirror) is 100 μm; the dry adhesive thickness of the acrylic pressure-sensitive adhesive solution (Henkel, Loctite 8087) is 35 μm; and the thickness of the transparent PET release film (Toray, Lumirror) is 38 μm. Example 3

[0033] As a third embodiment of the present application, the self-cleaning and anti-fog automobile glass film provided in this embodiment has the same layered structure and preparation process as the aforementioned Example 1.

[0034] However, the thickness of the polyurethane-SiO2 composite super-hydrophilic transparent coating in this embodiment is 12 μm; the thickness of the PET substrate (Toray, Lumirror) is 150 μm; the dry adhesive thickness of the acrylic pressure-sensitive adhesive solution (Henkel, Loctite 8087) is 50 μm; and the thickness of the transparent PET release film (Toray, Lumirror) is 50 μm.

[0035] The following table is the test data of the average light transmittance of the self-cleaning and anti-fog automobile glass film provided in Examples 1-3 above, and the static water contact angle (WCA) of the surface coating thereof.

[0036] Examples Static water contact angle (WCA), unit: ° Average light transmittance % Example 1 5.50 85.50 Example 2 5.50 85.50 Example 3 5.50 85.50

[0037] From the above test data, it can be seen that the self-cleaning and anti-fog automobile glass film provided by the present application has a super-hydrophilic surface layer with a static water contact angle of only 5.5°. At the same time, the average light transmittance of the entire film is as high as 85.50%.

[0038] The test methods for each performance in the above table are as follows:

[0039] 1. Static water contact angle

[0040] Select an automobile glass film, tear off the release film, and paste it on a 3 mm transparent glass. Use an SDC-200S contact angle tester to measure the static water contact angle of the surface layer of the automobile glass film. Each sample is measured 5 times, and the average value is recorded.

[0041] 2. Average light transmittance

[0042] Select an automobile glass film, tear off the release film, and paste it on a 3 mm transparent glass. Use an ultraviolet-visible spectrophotometer (Agilent Cary 5000) to measure the average light transmittance of the film, with a test range of 350-800 nm.

[0043] In addition, the abrasion resistance, anti-fog performance and weather resistance of the self-cleaning, anti-fog automobile glass film surface coating provided in the above embodiments are respectively determined.

[0044] The abrasion resistance of the coating is tested as follows: select an automobile glass film, tear off the release film, paste it on a 3mm transparent glass, and place it horizontally, pour sand at a vertical height of 50cm from the sample, so that the sand falls on the surface of the sample, and observe the damage to the surface of the coating. The contact angle of the surface of the tested sample is measured using a contact angle tester, and the final value of the contact angle of the surface of each sample is the average of 5 measured values on the sample.

[0045] The test results are as follows:

[0046] The contact angle of the surface of the coating of the automobile glass films of the above embodiments 1-3 fluctuates slightly with the increase of the mass of the sand, but the overall remains super-hydrophilic; when the mass of the sand increases to 1400g, the contact angle of the surface of the PU-SiO2 coating rises to 15.8°, and the coating loses the super-hydrophilic property; according to the area of the sample, it can be calculated that the maximum pressure that the coating can withstand is about 26kPa.

[0047] The anti-fog performance of the coating is tested as follows: select an automobile glass film, tear off the release film, paste it on a 3mm transparent glass, and place the sample on a beaker containing hot water at 100℃. A paper with text is placed below the beaker.

[0048] The test results are as follows:

[0049] The water droplets formed by condensation on the surface of the automobile glass films of the above embodiments 1-3 spread on the surface of the PU-SiO2 super-hydrophilic coating to form a water film, thereby eliminating the scattering of light. The results show that the surface of the PU-SiO2 coating has good anti-fog performance.

[0050] The abrasion resistance of the coating is tested as follows: select an automobile glass film, tear off the release film, paste it on a 3mm transparent glass, and place it outdoors, and measure the surface wettability every week for a total of 6 months.

[0051] The test results are as follows:

[0052] The automobile glass films of the above embodiments 1-3 are placed outdoors for 6 months, and the surface wettability does not change significantly, proving that the PU-SiO2 coating has good weather resistance and can withstand the test of the climate.

[0053] The utility model is not limited to the above best implementation, anyone can draw other various forms of product under the enlightenment of the utility model, but no matter make any change in its shape or structure, all have the same or similar technical scheme with the application, fall in the protection scope of the utility model.

Claims

1. A self-cleaning, anti-fog automotive glass film, characterized by The layered structure comprises, in sequence, a release film layer, a pressure-sensitive adhesive layer, a PET substrate layer and a polyurethane-SiO2 composite super-hydrophilic transparent coating layer.

2. A self-cleaning, anti-fog automotive glass film according to claim 1, characterized in that: The thickness of the polyurethane-SiO2 composite super-hydrophilic transparent coating layer is 5 μm-12 μm.

3. The self-cleaning, anti-fog automotive glass film according to claim 1, characterized in that: The thickness of the PET substrate layer is 50 μm-150 μm.

4. The self-cleaning, anti-fog automotive glass film according to claim 1, characterized in that: The thickness of the pressure-sensitive adhesive layer is 20 μm-50 μm.

5. The self-cleaning, anti-fog automotive glass film according to claim 1, characterized in that: The thickness of the release film layer is 23 μm-50 μm.

Images