High-transmittance composite automobile window film with red / yellow light therapy function and preparation method of high-transmittance composite automobile window film

Abstract

The invention discloses a high-transmittance composite automobile window film with a red / yellow light therapy function and a preparation method thereof, and relates to the field of automobile window films, the high-transmittance composite automobile window film comprises an ultraviolet absorption type PET base film layer with a thickness of 25-75 [mu] m, a UV R greater than or equal to 99%, and a VLT greater than or equal to 70%; the functional dimming layer is coated on the base film, the dry film thickness of the functional dimming layer is 5-20 microns, and the functional dimming layer is formed by curing coating liquid containing acrylic resin, a solvent and dye; the dye is a red light dye or a yellow light dye, and the addition amount of the dye is 0.01-5wt% of the total mass of the coating liquid; the visible light transmittance VLT of the composite automobile window film is 70-85%, and the transmittance RLT of the red light wave band of 620-750 nm is larger than or equal to 65% or the yellow light wave band of 570-600 nm. According to the high-transmittance composite automobile window film with the red / yellow light therapy function and the preparation method of the high-transmittance composite automobile window film, a single functional layer synchronously achieves the effects that UUV is larger than or equal to 99%, VLT is larger than or equal to 70%, and RLT / YLT is larger than or equal to 65%.

Description

Technical Field

[0001] This invention relates to automotive window film technology, specifically to a high-transparency composite automotive window film with red / yellow light therapy function and its preparation method. Background Technology

[0002] Most existing automotive window films on the market focus on functions such as heat insulation, ultraviolet protection, and privacy protection, but lack the ability to directionally regulate the spectrum of sunlight entering the car. If the window film had a spectrum regulation function, it could enhance the proportion of specific spectral bands that are beneficial to the human body, such as red light ≈630nm and yellow light ≈585nm, in the transmitted light, thereby achieving a certain red / yellow light therapy effect.

[0003] Red / yellow light therapy is an optical technology that uses visible light of specific wavelengths to irradiate the skin, gently stimulating cell metabolism and blood circulation, and promoting skin repair and conditioning. Red light therapy mainly promotes collagen production and accelerates tissue repair, while yellow light therapy helps soothe sensitivity and improve uneven skin tone and pigmentation.

[0004] However, under the premise of meeting the regulatory requirements of high visible light transmittance (VLT≥70%) and maintaining a natural appearance, the introduction of additional phototherapy bands usually faces three major technical contradictions: First, the spectrum contradiction, increasing the transmittance of red / yellow light often simultaneously increases other bands, resulting in a decrease in heat insulation performance or an increase in glare; second, the color contradiction, traditional anti-reflective methods are prone to causing film color distortion, increasing the safety hazards of nighttime driving; third, the process-cost contradiction, although multi-layer interference or vacuum coating can adjust the light, the equipment investment is large and the yield rate is low, making it difficult to support large-scale commercialization. Summary of the Invention

[0005] The purpose of this invention is to provide a high-transparency composite automotive window film with red / yellow phototherapy function and its preparation method, so as to overcome the above-mentioned shortcomings in the prior art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a high-transparency composite automotive window film with red / yellow light therapy function, comprising:

[0007] The ultraviolet-absorbing PET base film layer has a thickness of 25-75μm, UVR≥99%, and VLT≥70%;

[0008] The functional dimming layer coated on the base film has a dry film thickness of 5-20 μm and is formed by curing a coating liquid containing acrylic resin, solvent and dye.

[0009] The dye is a red or yellow dye, and the amount added is 0.01-5 wt% of the total mass of the coating liquid.

[0010] The composite automotive window film has a visible light transmittance (VLT) of 70-85%, and a red light transmittance (RLT) of ≥65% in the red light band (620-750nm) or a yellow light transmittance (YLT) of ≥65% in the yellow light band (570-600nm).

[0011] Furthermore, the acrylic resin is polymethyl methacrylate, and the solvent is ethyl acetate.

[0012] Furthermore, the red dye is selected from azo dyes or rare earth complex dyes, and the yellow dye is selected from quinoline dyes or azo dyes.

[0013] Furthermore, it also includes a nano-insulation layer disposed on the outside of the functional dimming layer, the insulation layer containing WO3 or ITO particles with a particle size of 10-40nm, a layer thickness of 20-100nm, and a near-infrared blocking rate (IRR) ≥ 80%.

[0014] A method for preparing a high-transparency composite automotive window film with red / yellow phototherapy function, applicable to the aforementioned high-transparency composite automotive window film with red / yellow phototherapy function, includes the following steps:

[0015] S1. Mix and stir acrylic resin, ethyl acetate solvent, red dye and / or yellow dye, and dispersant to form a uniform solution, and finally add curing agent to obtain coating liquid;

[0016] S2. Apply the coating solution obtained in S1 to the surface of the base film layer by scraping, and control the wet film thickness to be 10-40μm;

[0017] S3. Dry at 80℃±5℃ for 10-20 minutes to cure the coating liquid and form a functional dimming layer;

[0018] S4. Composite pressure-sensitive adhesive layer and release film layer onto the cured functional dimming layer.

[0019] Further, in S1, the amount of dye added is 0.01-5 wt% of the total mass of the coating liquid, the amount of dispersant added is 1.0 wt% of the solid mass of the acrylic resin, and the amount of curing agent added is 4.0 wt% of the solid mass of the acrylic resin.

[0020] Compared with the prior art, the high-transparency composite automotive window film with red / yellow light therapy function and its preparation method provided by the present invention have the following beneficial effects:

[0021] I. Synchronous implementation of a single functional layer: UVR≥99%, VLT≥70%, RLT / YLT≥65%;

[0022] Second, the wet process reduces equipment costs by more than 50%;

[0023] Third, the addition of trace amounts of dye avoids color deviation and ensures driving safety at night. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0025] Figure 1 This is a schematic cross-sectional view of the overall structure provided in an embodiment of the present invention;

[0026] Figure 2 This is a flowchart illustrating the preparation method of a high-transparency composite automotive window film with red / yellow phototherapy function, as provided in an embodiment of the present invention.

[0027] Explanation of reference numerals in the attached figures:

[0028] 1. Base film layer; 2. Functional dimming layer. Detailed Implementation

[0029] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0030] Example 1:

[0031] Please see Figure 1 High-transparency composite automotive window film with red / yellow light therapy function, including:

[0032] UV-absorbing PET base film layer 1, with a thickness of 25-75μm, UVR≥99%, VLT≥70%;

[0033] The functional dimming layer 2, coated on the base film, has a dry film thickness of 5-20 μm and is formed by curing a coating liquid containing acrylic resin, solvent and dye.

[0034] The dye is a red or yellow dye, and the amount added is 0.01-5 wt% of the total mass of the coating solution;

[0035] The visible light transmittance (VLT) of the composite automotive window film is 70-85%, and the red light transmittance (RLT) in the 620-750nm band is ≥65%, or the yellow light transmittance (YLT) in the 570-600nm band is ≥65%.

[0036] The acrylic resin is polymethyl methacrylate, and the solvent is ethyl acetate.

[0037] Red dyes are selected from azo dyes or rare earth complex dyes, while yellow dyes are selected from quinoline dyes or azo dyes.

[0038] It also includes a nano heat insulation layer disposed on the outside of the functional dimming layer 2. The heat insulation layer contains WO3 or ITO particles with a particle size of 10-40nm, a layer thickness of 20-100nm, and a near-infrared blocking rate (IRR) ≥80%.

[0039] Base film layer 1 is made of UV-absorbing PET with a thickness of 25-75μm, containing benzotriazole UV absorbers, with UVR≥99% and original VLT≥70%.

[0040] The functional dimming layer 2 has a matrix of polymethyl methacrylate (PMMA) and acrylic resin (solid content 10-50wt%), and the solvent is ethyl acetate;

[0041] The dye is a red-light azo / rare earth complex dye, such as solvent Red24 or yellow-light quinoline / azo dye, with an addition amount of 0.01-5 wt%.

[0042] The dry film thickness is 5-20 μm;

[0043] Target optical performance: RLT or YLT ≥ 65%, overall VLT 70-85%.

[0044] Example 2:

[0045] Please see Figure 2 This embodiment provides a technical solution based on Embodiment 1: a method for preparing a high-transparency composite automotive window film with red / yellow light therapy function, comprising the following steps:

[0046] S1. Mix and stir acrylic resin, ethyl acetate solvent, red dye and / or yellow dye, and dispersant to form a uniform solution, and finally add curing agent to obtain coating liquid;

[0047] S2. Apply the coating solution obtained in S1 to the surface of the base film layer 1 by scraping, and control the wet film thickness to be 10-40μm;

[0048] S3. Dry at 80℃±5℃ for 10-20 minutes to cure the coating liquid and form the functional dimming layer 2.

[0049] S4. Composite pressure-sensitive adhesive layer and release film layer on the cured functional dimming layer 2.

[0050] In S1, the amount of dye added is 0.01-5 wt% of the total mass of the coating liquid, the amount of dispersant added is 1.0 wt% of the solid mass of the acrylic resin, and the amount of curing agent added is 4.0 wt% of the solid mass of the acrylic resin.

[0051] Example 3:

[0052] Raw material selection:

[0053] The window base film is 50μm thick, with a VLT (vehicle temperature range) of approximately 76.34%.

[0054] Functional dimming layer 2: 100g PMMA resin (50wt% solids), 100g ethyl acetate, 0.5wt% Red24 dye (to the resin solids), 1.0wt% dispersant, and 4.0wt% curing agent.

[0055] Preparation process:

[0056] The resin and solvent were mixed and stirred at room temperature for 30 minutes to obtain a transparent solution. Dye and dispersant were added to the transparent solution and stirred for 5 minutes. Then, curing agent was added and stirred lightly for 5 minutes to obtain a coating liquid. The coating liquid was evenly coated on the surface of the base film layer 1 using a 40μm doctor blade and baked and cured in an 80℃ hot air oven for 15 minutes. After cooling, pressure-sensitive adhesive and release film were laminated and rolled up for use. HunterLab UltraScanVIS, D65 light source, 2° viewing angle; three measurements were taken for each sample and the average value was calculated (n=3, SD≤0.3%).

[0057] The manufactured automotive window film was tested according to GB / T9656-2021, and the data are shown in Table 1:

[0058] sample VLT (%) RLT (%) Commercial PET film (comparison) 76.34 65.38 This embodiment of automotive window film 74.01 70.34

[0059] Example 4:

[0060] In Example 3, 0.5 wt% of Yel Low 93 dye (to the resin solids content) was added to the formulation, while the other conditions remained unchanged.

[0061] Test results: VLT 73.68%, RLT 71.14%.

[0062] Example 5:

[0063] The Red135 dye was used at 1 wt% (to the resin solids content), and the base film layer 1 was processed in the same way as in Example 3.

[0064] Test results: VLT 76.58%, RLT 66.87%.

[0065] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A high-transparency composite automotive window film with red / yellow light therapy function, characterized in that, include: The ultraviolet-absorbing PET base film layer has a thickness of 25-75μm, UVR≥99%, and VLT≥70%; The functional dimming layer coated on the base film has a dry film thickness of 5-20 μm and is formed by curing a coating liquid containing acrylic resin, solvent and dye. The dye is a red or yellow dye, and the amount added is 0.01-5 wt% of the total mass of the coating liquid; The composite automotive window film has a visible light transmittance (VLT) of 70-85%, and a red light transmittance (RLT) of ≥65% in the red light band (620-750nm) or a yellow light transmittance (YLT) of ≥65% in the yellow light band (570-600nm).

2. The high-transparency composite automotive window film with red / yellow light therapy function according to claim 1, characterized in that, The acrylic resin is polymethyl methacrylate, and the solvent is ethyl acetate.

3. The high-transparency composite automotive window film with red / yellow light therapy function according to claim 1, characterized in that, The red dye is selected from azo dyes or rare earth complex dyes, and the yellow dye is selected from quinoline dyes or azo dyes.

4. The composite automotive window film according to claim 1, characterized in that: It also includes a nano heat insulation layer disposed on the outside of the functional dimming layer. The heat insulation layer contains WO3 or ITO particles with a particle size of 10-40nm, a layer thickness of 20-100nm, and a near-infrared blocking rate (IRR) ≥ 80%.

5. A method for preparing a high-transparency composite automotive window film with red / yellow phototherapy function, applicable to the high-transparency composite automotive window film with red / yellow phototherapy function as described in any one of claims 1-4, characterized in that, Includes the following steps: S1. Mix and stir acrylic resin, ethyl acetate solvent, red dye and / or yellow dye, and dispersant to form a uniform solution, and finally add curing agent to obtain coating liquid; S2. Apply the coating solution obtained in S1 to the surface of the base film layer by scraping, and control the wet film thickness to be 10-40μm; S3. Dry at 80℃±5℃ for 10-20 minutes to cure the coating liquid and form a functional dimming layer; S4. Composite pressure-sensitive adhesive layer and release film layer onto the cured functional dimming layer.

6. The method for preparing a high-transmittance composite automotive window film with red / yellow phototherapy function according to claim 5, characterized in that, The amount of dye added in S1 is 0.01-5 wt% of the total mass of the coating liquid, the amount of dispersant added is 1.0 wt% of the solid mass of the acrylic resin, and the amount of curing agent added is 4.0 wt% of the solid mass of the acrylic resin.

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