Infrared high-transmittance regression reflection film and preparation method thereof

Abstract

The invention relates to an infrared high-transmittance regression reflection film and a preparation method thereof, and belongs to the technical field of unsaturated polyester. The infrared high-permeability film is prepared from the following components in parts by weight: 100 parts of modified polyester resin, 1.8-2.4 parts of a visible light cut-off agent, 1.2-1.5 parts of a lubricant and 0.15-0.2 part of an antistatic agent; the modified polyester resin is prepared by the following steps: performing ring opening on dihydric alcohol diglycidyl ether and 2, 2-difluoroethylamine to prepare a compound with an alcohol amine structure, namely a modified monomer, and performing co-esterification condensation on the modified monomer, ethylene glycol and terephthalic acid to form modified monomer block polyester resin; in the blending film preparation process, the modified polyester resin and the metal phthalocyanine derivative have a synergistic effect, so that the dispersity of the metal phthalocyanine derivative is improved, scattering of light waves in a film layer is reduced, the transmittance of infrared light is improved, the regression attenuation rate is reduced, and the stability of a photoelectric system is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of unsaturated polyesters, and in particular relates to an infrared high-transmittance retro-reflective film and a preparation method thereof. Background Art

[0002] Traditional capacitive touch screens rely on sensing capacitance changes to identify touches, but have limitations such as low sensitivity, susceptibility to interference, and difficulty in adapting well to environmental conditions such as fog and rain. Compared with capacitive touch screens, optical touch screens use active optical sensors to scan the touch screen surface and locate fingers by identifying changes in reflected light from the touch point. They have the advantages of high sensitivity, good anti-interference and environmental adaptability, and are widely used in electronic devices such as smart phones, tablets, and laptops.

[0003] As a key component, retro-reflective film plays a vital role in the working principle of touch screens. In optical touch screens, there is usually a set of light sources and sensors to detect the touch position, and the retro-reflective film is used to reflect light waves, and the touch position is recognized by sensing the displacement change of the object on the reflected light waves. Infrared light is invisible to the human eye, so it does not interfere with the user's visual experience during use, which means that the user will not see the light source when operating the touch screen, providing a cleaner and more professional display effect. However, the existing retro-reflective film is easily interfered by visible light during the infrared light emission process, resulting in low touch accuracy. Summary of the invention

[0004] In order to solve the technical problems mentioned in the background technology, the object of the present invention is to provide an infrared high-transmittance retro-reflective film and a preparation method thereof.

[0005] The purpose of the present invention can be achieved through the following technical solutions: The invention discloses an infrared high-transmittance retro-reflective film, belonging to the technical field of unsaturated polyester, which is formed by bonding an infrared high-transmittance film and a retro-reflective film, wherein the infrared high-transmittance film comprises, by weight, 100 parts of a modified polyester resin, 1.8-2.4 parts of a visible light cutoff agent, 1.2-1.5 parts of a lubricant and 0.15-0.2 parts of an antistatic agent; and the preparation method of the infrared high-transmittance film comprises the following steps: premixing the modified polyester resin, the visible light cutoff agent, the lubricant and the antistatic agent, plasticizing and extruding at 280±5°C, and calendering and cooling to obtain the infrared high-transmittance film.

[0006] Furthermore, the visible light cutoff agent is a metal phthalocyanine derivative, which has good visible light cutoff and infrared transmission properties and has good compatibility with the modified polyester resin.

[0007] Furthermore, the infrared high-transmittance film has a thickness of 100-150 μm, and within this thickness range, it has good cutoff properties for visible light and has little effect on the transmittance of infrared light.

[0008] The preparation method of the infrared high-transmittance retro-reflective film is as follows: unrolling the retro-reflective film and laying it flat, applying optical glue on the surface, attaching the infrared high-transmittance film, and naturally curing for 24 hours to obtain the infrared high-transmittance retro-reflective film.

[0009] The modified polyester resin is prepared by the following method: Step A1: diol diglycidyl ether, aluminum chloride and anhydrous tetrahydrofuran are mixed, dry nitrogen is introduced for protection, the temperature is raised to 40-55° C., 2,2-difluoroethylamine is slowly added, and the mixture is stirred for reaction for 4-6 hours. After the reaction is completed, tetrahydrofuran is removed by rotary evaporation to obtain a modified monomer.

[0010] Furthermore, the diol diglycidyl ether is one of ethylene glycol diglycidyl ether and hexanediol diglycidyl ether.

[0011] Furthermore, the feed ratio of diol diglycidyl ether, 2,2-difluoroethylamine, aluminum chloride and anhydrous tetrahydrofuran is 0.1 mol: 0.105-0.11 mol: 20-30 mg: 40-60 mL. Under the promotion of aluminum chloride, 2,2-difluoroethylamine and diol diglycidyl ether open the ring to form an alcoholamine compound.

[0012] Step A2: premix terephthalic acid, ethylene glycol and modified monomer as composite monomers, add antimony trioxide and mix them, under nitrogen protection, heat to 190-220°C for esterification reaction for 2.8-3.5h, then add tetrabutyl titanate and mix, heat to 265-280°C, reduce pressure to 1kPa, polycondense for 6.2-7.5h, cool the discharged material to obtain modified polyester resin.

[0013] Furthermore, the alcohol-acid ratio in the composite monomer is 1.2-1.4, the molar ratio of ethylene glycol to the modified monomer is 1:0.12-0.18; the amount of antimony trioxide is 0.06-0.08wt% of the composite monomer, and the amount of tetrabutyl titanate is 0.02-0.03wt% of the composite monomer; the modified monomer and ethylene glycol are co-esterified and condensed with terephthalic acid to form a polyester resin with a modified monomer block.

[0014] Beneficial effects of the present invention: The present invention is based on the existing diamond-grade retro-reflective film, and through a composite infrared high-transmittance film, the composite film material is endowed with excellent visible light cutoff and infrared light high-transmittance properties; the infrared high-transmittance film is formed by a modified polyester resin independently developed as a film-forming agent, and a metal phthalocyanine derivative is used as a visible light cutoff agent, wherein the modified polyester resin is prepared by ring-opening of diol diglycidyl ether and 2,2-difluoroethylamine to form a compound with an alcoholamine structure, namely a modified monomer, and then the modified monomer is co-esterified and condensed with ethylene glycol and terephthalic acid to form a polyester resin with a modified monomer block; in the process of blending and film making, the amine structure introduced into the modifier block forms a hydrogen bond with nitrogen in the metal phthalocyanine derivative, thereby improving the dispersibility of the metal phthalocyanine derivative in the blending process and enhancing the metal phthalocyanine derivative's The full absorption and cutoff of visible light reduces the interference of visible light in the process of regression reflection, which is of great significance to reducing the regression attenuation rate. Thanks to the hydrogen bonding, the fluorine-containing ether structure is attached to the surface of the metal phthalocyanine derivative particles. On the one hand, the surface of the metal phthalocyanine derivative is modified to reduce its surface defects, making the surface smoother and reducing the scattering of infrared light. On the other hand, after fluorine element doping, the refractive index of the polymer material on the surface of the metal phthalocyanine derivative is reduced, and the degree of diffuse reflection is reduced, thereby reducing the transmittance of infrared light. In the test, the infrared high-transmittance film has a high cutoff for the visible light band, high transmittance in the infrared light band, and a lower regression attenuation rate in the composite film, which is beneficial to improving the stability of the optoelectronic system. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0016] Figure 1 It is the transmittance curve of the infrared high-transmittance film of the present invention at a wavelength of 400-940nm. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] Example 1: Preparation of infrared high-transmittance retro-reflective film, as follows: (1) Preparation of infrared high-transmittance film Step A1: Mix ethylene glycol diglycidyl ether, aluminum trichloride and anhydrous tetrahydrofuran, introduce dry nitrogen protection, heat to 40°C, stir at 120rpm and slowly add 2,2-difluoroethylamine to react for 6h, wherein the feed ratio of ethylene glycol diglycidyl ether, 2,2-difluoroethylamine, aluminum trichloride and anhydrous tetrahydrofuran is 0.1mol:0.105mol:20mg:40mL. After the reaction, remove tetrahydrofuran by rotary evaporation to obtain a modified monomer.

[0019] Step A2: Take terephthalic acid, ethylene glycol, and modified monomer premix as composite monomer, add antimony trioxide and mix, under nitrogen protection, heat to 190°C for esterification reaction for 3.5 hours, then add tetrabutyl titanate and mix, heat to 265°C, reduce pressure to 1 kPa, and condense for 7.5 hours, wherein the alcohol-acid ratio in the composite monomer is 1.4, the molar ratio of ethylene glycol to the modified monomer is 1:0.12, the amount of antimony trioxide is 0.08wt% of the composite monomer, the amount of tetrabutyl titanate is 0.02wt% of the composite monomer, the discharge is cooled, and the modified polyester resin is obtained.

[0020] According to the weight ingredients, 100 parts of modified polyester resin were prepared by the present invention; 1.8 parts of visible light cutoff agent were selected from copper phthalocyanine of Xi'an Qiyue Biotechnology Co., Ltd.; 1.2 parts of lubricant were selected from KJ-B01 silicone powder of Hangzhou Kaijie Plastic Technology Co., Ltd.; 0.2 parts of antistatic agent were selected from LQX-30 antistatic agent of Shenzhen Hongtai Xuanyou New Materials Co., Ltd.

[0021] The above raw materials were premixed, plasticized and extruded at 280±5°C, calendered and cooled to form a film material with a thickness of 120 μm, thereby obtaining an infrared high-transmittance film.

[0022] (2) Preparation of infrared high-transmittance retro-reflective film Select 3M's 4090T diamond-grade film and retro-reflective film, unroll and lay flat, apply EPO-TEK® 301-1 optical glue on the surface, and control the glue application amount to 100±5g / m 2 , attach the infrared high-transmittance film, and naturally cure it for 24 hours to obtain the infrared high-transmittance retro-reflective film.

[0023] Example 2: Preparation of infrared high-transmittance retro-reflective film, as follows: (1) Preparation of infrared high-transmittance film Step A1: Mix ethylene glycol diglycidyl ether, aluminum trichloride and anhydrous tetrahydrofuran, introduce dry nitrogen protection, heat to 45°C, stir at 150rpm and slowly add 2,2-difluoroethylamine to react for 5.5h, wherein the feed ratio of ethylene glycol diglycidyl ether, 2,2-difluoroethylamine, aluminum trichloride and anhydrous tetrahydrofuran is 0.1mol:0.105mol:22mg:45mL. After the reaction, remove tetrahydrofuran by rotary evaporation to obtain a modified monomer.

[0024] Step A2: Take terephthalic acid, ethylene glycol, and modified monomer premix as composite monomer, add antimony trioxide and mix, under nitrogen protection, heat to 200°C for esterification reaction for 3.2 hours, then add tetrabutyl titanate and mix, heat to 270°C, reduce pressure to 1 kPa, and condense for 7 hours, wherein the alcohol-acid ratio in the composite monomer is 1.3, the molar ratio of ethylene glycol to the modified monomer is 1:0.15, the amount of antimony trioxide is 0.07wt% of the composite monomer, the amount of tetrabutyl titanate is 0.02wt% of the composite monomer, the discharge is cooled, and the modified polyester resin is obtained.

[0025] According to the weight ingredients, 100 parts of modified polyester resin were prepared by the present invention; 2.2 parts of visible light cutoff agent were selected from copper phthalocyanine of Xi'an Qiyue Biotechnology Co., Ltd.; 1.5 parts of lubricant were selected from KJ-B01 silicone powder of Hangzhou Kaijie Plastic Technology Co., Ltd.; 0.18 parts of antistatic agent were selected from LQX-30 antistatic agent of Shenzhen Hongtai Xuanyou New Materials Co., Ltd.

[0026] The above raw materials were premixed, plasticized and extruded at 280±5°C, calendered and cooled to form a film material with a thickness of 120 μm, thereby obtaining an infrared high-transmittance film.

[0027] (2) Preparation of infrared high-transmittance retro-reflective film Select 3M's 4090T diamond-grade film and retro-reflective film, unroll and lay flat, apply EPO-TEK® 301-1 optical glue on the surface, and control the glue application amount to 100±5g / m 2 , attach the infrared high-transmittance film, and naturally cure it for 24 hours to obtain the infrared high-transmittance retro-reflective film.

[0028] Example 3: Preparation of infrared high-transmittance retro-reflective film, as follows: (1) Preparation of infrared high-transmittance film Step A1: Mix hexanediol diglycidyl ether, aluminum trichloride and anhydrous tetrahydrofuran, introduce dry nitrogen protection, heat to 55°C, stir at 180rpm and slowly add 2,2-difluoroethylamine to react for 4h, wherein the feed ratio of hexanediol diglycidyl ether, 2,2-difluoroethylamine, aluminum trichloride and anhydrous tetrahydrofuran is 0.1mol:0.11mol:30mg:60mL. After the reaction, remove tetrahydrofuran by rotary evaporation to obtain a modified monomer.

[0029] Step A2: Take terephthalic acid, ethylene glycol, and modified monomer premix as composite monomer, add antimony trioxide and mix, under nitrogen protection, heat to 220°C for esterification reaction for 2.8 hours, then add tetrabutyl titanate and mix, heat to 280°C, reduce pressure to 1 kPa, and condense for 6.2 hours, wherein the alcohol-acid ratio in the composite monomer is 1.2, the molar ratio of ethylene glycol to the modified monomer is 1:0.18, the amount of antimony trioxide is 0.06wt% of the composite monomer, the amount of tetrabutyl titanate is 0.03wt% of the composite monomer, the discharge is cooled, and the modified polyester resin is obtained.

[0030] According to the weight ingredients, 100 parts of modified polyester resin were prepared by the present invention; 2.4 parts of visible light cutoff agent were selected from copper phthalocyanine of Xi'an Qiyue Biotechnology Co., Ltd.; 1.4 parts of lubricant were selected from KJ-B01 silicone powder of Hangzhou Kaijie Plastic Technology Co., Ltd.; 0.15 parts of antistatic agent were selected from LQX-30 antistatic agent of Shenzhen Hongtai Xuanyou New Materials Co., Ltd.

[0031] The above raw materials were premixed, plasticized and extruded at 280±5°C, calendered and cooled to form a film material with a thickness of 120 μm, thereby obtaining an infrared high-transmittance film.

[0032] (2) Preparation of infrared high-transmittance retro-reflective film Select 3M's 4090T diamond-grade film and retro-reflective film, unroll and lay flat, apply EPO-TEK® 301-1 optical glue on the surface, and control the glue application amount to 100±5g / m 2 , attach the infrared high-transmittance film, and naturally cure it for 24 hours to obtain the infrared high-transmittance retro-reflective film.

[0033] Example 4: Preparation of infrared high-transmittance retro-reflective film, as follows: (1) Preparation of infrared high-transmittance film Step A1: Mix hexanediol diglycidyl ether, aluminum trichloride and anhydrous tetrahydrofuran, introduce dry nitrogen protection, heat to 50°C, stir at 180rpm and slowly add 2,2-difluoroethylamine to react for 4.5h, wherein the feed ratio of hexanediol diglycidyl ether, 2,2-difluoroethylamine, aluminum trichloride and anhydrous tetrahydrofuran is 0.1mol:0.108mol:26mg:55mL. After the reaction, remove tetrahydrofuran by rotary evaporation to obtain a modified monomer.

[0034] Step A2: Take terephthalic acid, ethylene glycol, and modified monomer premix as composite monomer, add antimony trioxide and mix, under nitrogen protection, heat to 210°C for esterification reaction for 3 hours, then add tetrabutyl titanate and mix, heat to 275°C, reduce pressure to 1 kPa, and condense for 6.5 hours, wherein the alcohol-acid ratio in the composite monomer is 1.3, the molar ratio of ethylene glycol to the modified monomer is 1:0.16, the amount of antimony trioxide is 0.07wt% of the composite monomer, the amount of tetrabutyl titanate is 0.03wt% of the composite monomer, the discharge is cooled, and the modified polyester resin is obtained.

[0035] According to the weight ingredients, 100 parts of modified polyester resin were prepared by the present invention; 2 parts of visible light cutoff agent were selected from copper phthalocyanine of Xi'an Qiyue Biotechnology Co., Ltd.; 1.3 parts of lubricant were selected from KJ-B01 silicone powder of Hangzhou Kaijie Plastic Technology Co., Ltd.; 0.17 parts of antistatic agent were selected from LQX-30 antistatic agent of Shenzhen Hongtai Xuanyou New Materials Co., Ltd.

[0036] The above raw materials were premixed, plasticized and extruded at 280±5°C, calendered and cooled to form a film material with a thickness of 120 μm, thereby obtaining an infrared high-transmittance film.

[0037] (2) Preparation of infrared high-transmittance retro-reflective film Select 3M's 4090T diamond-grade film and retro-reflective film, unroll and lay flat, apply EPO-TEK® 301-1 optical glue on the surface, and control the glue application amount to 100±5g / m 2 , attach the infrared high-transmittance film, and naturally cure it for 24 hours to obtain the infrared high-transmittance retro-reflective film.

[0038] Comparative Example 1, referring to Example 4, during the synthesis of the modified polyester resin, ethylene glycol was used to replace the modified monomer in an equimolar amount, and the rest of the implementation process was exactly the same.

[0039] Comparative Example 2, using the polyester resin prepared in Comparative Example 1, using an equal amount of BZH type visible light cutoff agent produced by Shanghai Yuansu Chemical Technology Co., Ltd. to replace the copper phthalocyanine in this case, and the rest of the implementation process is exactly the same.

[0040] Samples were taken from the infrared high-transmittance film prepared as above, and the light transmittance in the 400-940nm band was tested according to GB / T 36403-2018 standard. Figure 1 As shown; Depend on Figure 1 It can be seen that the infrared high-transmittance film prepared in the embodiment has a higher cutoff for the visible light band and a high transmittance in the infrared light band. Compared with Comparative Example 1, the cutoff rate for visible light is higher and the transmittance for infrared light is higher. Compared with Comparative Example 2, Comparative Example 2 has a higher cutoff for light in the band below 700nm and a lower nitrogen infrared transmittance.

[0041] Samples were taken from the infrared high-transmittance retro-reflective film prepared as above, and the reflectivity at wavelengths of 850nm and 940nm was measured by spectrophotometry. The 0° retro-reflectivity ρ 0 As a benchmark, detect the 45° regression reflectivity ρ 1 , calculate the regression decay rate Δρ = (ρ 0 -ρ 1 ) / ρ 0 ×100%, as shown in Table 1: It can be seen from the test results in Table 1 that the 0° retroreflectivity of the infrared high-transmittance retroreflective film prepared in the embodiment is relatively high, and the retroreflectivity attenuation rate is lower than that of the comparative example at wavelengths of 850nm and 940nm, which makes the large-angle attenuation of the retroreflective system lower, which is beneficial to improving the stability of the optoelectronic system.

[0042] In the description of the specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0043] The above contents are merely examples and explanations of the concept of the present invention. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the concept of the invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

Claims

1. An infrared high-transmittance retro-reflective film, which is formed by bonding an infrared high-transmittance film and a retro-reflective film, characterized in that: The infrared high-transmittance film comprises, by weight: 100 parts of modified polyester resin, 1.8-2.4 parts of visible light cutoff agent, 1.2-1.5 parts of lubricant and 0.15-0.2 parts of antistatic agent; The modified polyester resin is prepared by the following method: Step A1: diol diglycidyl ether, aluminum chloride and anhydrous tetrahydrofuran are mixed, dry nitrogen is introduced for protection, the temperature is raised to 40-55° C., 2,2-difluoroethylamine is slowly added, and the mixture is stirred for reaction for 4-6 hours. After the reaction is completed, tetrahydrofuran is removed by rotary evaporation to obtain a modified monomer; Step A2: premix terephthalic acid, ethylene glycol and modified monomer as composite monomers, add antimony trioxide and mix them, under nitrogen protection, heat to 190-220°C for esterification reaction for 2.8-3.5h, then add tetrabutyl titanate and mix, heat to 265-280°C, reduce pressure to 1kPa, polycondense for 6.2-7.5h, cool the discharged material to obtain modified polyester resin.

2. The infrared high-transmittance retro-reflective film according to claim 1, characterized in that: The diol diglycidyl ether is one of ethylene glycol diglycidyl ether and hexanediol diglycidyl ether.

3. The infrared high-transmittance retro-reflective film according to claim 2, characterized in that: The feed ratio of diol diglycidyl ether, 2,2-difluoroethylamine, aluminum chloride and anhydrous tetrahydrofuran is 0.1 mol: 0.105-0.11 mol: 20-30 mg: 40-60 mL.

4. The infrared high-transmittance retro-reflective film according to claim 3, characterized in that: The alcohol-acid ratio in the composite monomer is 1.2-1.4, the molar ratio of ethylene glycol to the modified monomer is 1:0.12-0.18; the amount of antimony trioxide is 0.06-0.08wt% of the composite monomer, and the amount of tetrabutyl titanate is 0.02-0.03wt% of the composite monomer.

5. The infrared high-transmittance retro-reflective film according to claim 1, characterized in that: The visible light cutoff agent is a metal phthalocyanine derivative.

6. The infrared high-transmittance retro-reflective film according to any one of claims 1 to 5, characterized in that: The preparation method of the infrared high-transmittance retro-reflective film is as follows: premixing the modified polyester resin, the visible light cutoff agent, the lubricant and the antistatic agent, plasticizing and extruding at 280±5°C, calendering and cooling, and obtaining the infrared high-transmittance film.

7. The infrared high-transmittance retro-reflective film according to claim 6, characterized in that: The thickness of the infrared high transmittance film is 100-150μm.

8. The method for preparing an infrared high-transmittance retro-reflective film according to claim 1, characterized in that: Specifically, the retro-reflective film is unrolled and laid flat, optical glue is scraped on the surface, an infrared high-transmittance film is attached, and the film is naturally cured for 24 hours to obtain an infrared high-transmittance retro-reflective film.

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