Coating film capable of blocking infrared rays and ultraviolet rays as well as preparation method and application of coating film

Abstract

The invention discloses a transparent coating film capable of blocking infrared rays and ultraviolet rays and a preparation method and application thereof.The transparent coating film comprises a base film, a coating, gum and a release film, the base film is made of a high polymer material, the thickness of the base film is 50-200 microns, the light transmittance is larger than 90%, and the haze is smaller than 0.5%; the coating is attached to the front surface of the base film, the thickness of the coating is 10-15 microns, and the coating is prepared from the following raw materials in percentage by mass: 28.6-57.2% of fluorocarbon resin, 0-28.6% of acrylic resin, 5.7% of an isocyanate curing agent, 2-3% of nano cesium tungsten bronze (CsXWO3), 2% of an ultraviolet light absorber, 2% of a light stabilizer, 2% of a silane coupling agent, 0.5% of a flatting agent, 0.5% of a defoaming agent and the balance of solvent methylbenzene or xylene; the back adhesive is attached to the back surface of the base film, the light transmittance is greater than 99%, and the thickness is 10-50 microns; and the release film is attached to the back adhesive. The transparent coating film provided by the invention has excellent heat insulation property, ultraviolet aging resistance and high weather resistance, and can be widely applied to the fields of buildings, automobiles, agricultural greenhouses and the like.

Description

Technical Field

[0001] The present invention belongs to the technical field of functional thin films, and specifically discloses a coating film for blocking infrared rays and ultraviolet rays, a preparation method thereof, and an application thereof. Background Art

[0002] With the increasing demand for energy conservation, environmental protection and healthy life among people, functional thin film materials are increasingly widely used in fields such as architecture, automobiles, and agriculture. Infrared rays and ultraviolet rays are important components of the solar spectrum. Excessive infrared rays will cause the indoor temperature to rise and increase the energy consumption of air conditioners; while excessive ultraviolet rays will cause damage to human skin, indoor furniture, automobile interiors, etc. Therefore, it is of great practical significance to develop a coating film that can simultaneously block infrared rays and ultraviolet rays and has high weather resistance and transparency. At present, common functional thin films on the market mostly adopt a single-function design, such as only having the function of blocking ultraviolet rays or reflecting infrared rays, and their weather resistance is poor. Problems such as yellowing and peeling are likely to occur after long-term use. Therefore, there is an urgent need for a multifunctional coating film with excellent comprehensive performance to meet the market demand.

[0003] In view of this, it is necessary to make improvements to the existing technology to solve the problems existing in the existing technology. Summary of the Invention

[0004] The purpose of the present invention is to disclose a coating film for blocking infrared rays and ultraviolet rays, a preparation method thereof, and an application thereof, so as to solve the problems existing in the background art.

[0005] To achieve the above purpose, the present invention provides the following technical solutions: A transparent coating film for blocking infrared rays and ultraviolet rays, the coating film includes a base film and a coating layer, wherein, The base film is made of a polymer material, with a thickness of 50 - 200 μm, a light transmittance > 90%, and a haze < 0.5%; The coating layer is attached to the front surface of the base film, with a thickness of 10 - 15 μm. The preparation raw materials of the coating layer include the following components (by mass percentage): fluorocarbon resin 28.6 - 57.2%, acrylic resin 0 - 28.6% (the sum of the fluorocarbon resin and the acrylic resin is 57.2%), isocyanate curing agent 5.7%, nano cesium tungsten bronze (Cs X2-3% of (WO3), 2% of ultraviolet absorber, 2% of light stabilizer, 2% of silane coupling agent, 5‰ of leveling agent, 5‰ of defoamer. The silane coupling agent uses the epoxy group type, such as KH560, and the specific grades include A-187 (Union Carbide Corporation, USA), KBM-403 (Shin-Etsu Chemical Co., Ltd., Japan), etc. Both the leveling agent and the defoamer use silicone or fluorocarbon additives of these strong types. The leveling agent is selected such as BYK 333, Efka EFKA-3777, etc. The defoamer is selected such as BYK066, BYK 088, etc. The rest is the solvent toluene or xylene; Among the components, fluorocarbon resin and acrylic resin are used as the film-forming substrate and are the framework of the coating. Due to the relatively large bond energy of the F-C bonds contained in the fluorocarbon resin, it has good stability in various environments, so it has excellent weather resistance. The acrylic resin has better impact resistance, higher hardness and better wear resistance compared with the fluorocarbon resin. The performance of the coating can be adjusted by adjusting the content of the acrylic resin.

[0006] The isocyanate curing agent and the above two resins can form a three-dimensional network structure with a high degree of crosslinking through the chemical reaction of -NCO and -OH, further improving the chemical stability and weather resistance of the coating.

[0007] Nanometer cesium tungsten bronze (Cs X WO3) can effectively absorb infrared light, making the coating have a high infrared barrier rate while maintaining a high light transmittance. The ultraviolet absorber can absorb ultraviolet light and convert it into harmless heat energy, and the light stabilizer can capture the free radicals generated during the photo-oxidation reaction. The two work together to keep the coating's performance unchanged during long-term exposure in the air environment. The silane coupling agent can act between the inorganic interface and the organic interface, connecting them with ether bonds (-O-), thereby improving the adhesion of the coating. The leveling agent and the defoamer can ensure that the coating has a good appearance during construction without abnormal phenomena such as horizontal and vertical streaks, shrinkage holes, and bubble points.

[0008] As a further improvement of the present invention, it also includes an adhesive and a release film; The adhesive is attached to the back of the base film, with a light transmittance > 99% and a thickness of 10 - 50μm. During construction, the product can be attached to the surface to be decorated through the adhesive; the adhesive has high transparency, such as the 3M8146 series, the Tesa tesa 694 series, etc.; The release film is attached to the adhesive and is composed of PET and a transparent release layer. The surface of the PET is subjected to corona or plasma treatment to make its surface dyne value ≥ 56 dyne / cm for the easy attachment of the release layer. The release layer is composed of a silicone oil release agent, with a release force of 3 - 5 g / in, the PET thickness is 50 - 100um, and the release layer thickness is 0.1 - 0.5um. The release film can play a protective role and is easy to operate, and can be torn off during use.

[0009] As a further improvement of the present invention, the fluorocarbon resin is a vinyl ether-modified fluorocarbon resin with a high hydroxyl value, and the hydroxyl value > 50 mgKOH / g. The vinyl ether modification greatly improves the polarity of the fluorocarbon resin, enabling it to be better mixed with other types of resins. When the hydroxyl value > 50 mgKOH / g, the resin has a high -OH content, which can greatly improve the crosslinking density of -NCO and -OH, form a high-performance three-dimensional network polymer, and improve the weather resistance of the coating.

[0010] As a further improvement of the present invention, the acrylic resin is a high-hydroxyl-value acrylic resin, and the hydroxyl value > 50 mgKOH / g. When the hydroxyl value > 50 mgKOH / g, the resin has a high -OH content, which can greatly improve the crosslinking density of -NCO and -OH, form a high-performance three-dimensional network polymer, and improve the weather resistance of the coating.

[0011] As a further improvement of the present invention, the isocyanate curing agent is an HDI trimer type, and its molecule does not contain unsaturated bonds, having better weather resistance. Such as Covestro Desmodur N3300, Asahi Kasei TPA-90SB, etc.

[0012] As a further improvement of the present invention, the ultraviolet absorber is a mixture of triazine and benzotriazole types, and the light stabilizer is a hindered amine type. For example, using the following combination of ultraviolet absorber and light stabilizer, ultraviolet absorber UV1164 (triazine): UV234 (benzotriazole) = 1:1, light stabilizer UV770 (hindered amine).

[0013] As a further improvement of the present invention, the base film is any one of polyethylene terephthalate (PET), polycarbonate (PC), polyamide (PA), polyethylene naphthalate (PEN), or polymethyl methacrylate (PMMA).

[0014] A method for preparing a transparent coating film that blocks infrared and ultraviolet rays, comprising the following steps: (1) Perform corona or plasma treatment on the coating surface of the transparent substrate to make its surface dyne value ≥ 56 dyne / cm, and reserve it for use; (2) Add the isocyanate curing agent to toluene or xylene, and the addition ratio is isocyanate curing agent: solvent = 1:3 - 5 (mass ratio), stir with a high-speed disperser for 5 min, and set the rotation speed to 500 r / min to obtain a uniformly mixed dispersion; (3) Add the ultraviolet absorber and the light stabilizer to toluene or xylene, with the addition ratio being ultraviolet absorber: light stabilizer: solvent = 1:1:5 - 10 (mass ratio). Stir with a high-speed disperser for 20 min, and set the rotation speed at 2000 r / min to obtain a uniformly mixed dispersion; (4) Add nano cesium tungsten bronze (Cs X WO3) to toluene or xylene, introduce it into a nano sand mill, and grind for 4 h to obtain a uniformly mixed dispersion. The solid content of the dispersion is 20 - 30%; (5) Mix the fluorocarbon resin, acrylic resin, the isocyanate curing agent dispersion in step (2), the ultraviolet absorber and light stabilizer dispersion in step (3), the nano cesium tungsten bronze (Cs X WO3) dispersion in step (4), silane coupling agent, leveling agent, defoaming agent and toluene or xylene in proportion. The ratio (mass percentage) is: fluorocarbon resin 28.6 - 57.2%, acrylic resin 0 - 28.6% (the sum of fluorocarbon resin and acrylic resin is 57.2%), isocyanate curing agent 5.7%, nano cesium tungsten bronze (Cs X WO3) 2 - 3%, ultraviolet absorber 2%, light stabilizer 2%, silane coupling agent 2%, leveling agent 5‰, defoaming agent 5‰, and the rest is the solvent toluene or xylene. Stir evenly to obtain the functional coating paint; (6) Uniformly coat the functional coating paint on the coating surface of the transparent substrate, and after drying and curing, obtain a highly weather-resistant transparent coating film with infrared and ultraviolet barrier properties; (7) Attach an adhesive on the other side of the base film, and then laminate a release film.

[0015] As a further improvement of the present invention, in step (6), the drying and curing conditions are: put the base film coated with the coating liquid into an oven at 130 °C, keep it for 3 min to achieve surface drying, and then transfer it to an oven at 60 °C and keep it for 48 h to complete curing.

[0016] Application of a transparent coating film that blocks infrared rays and ultraviolet rays in the preparation of automotive glass, agricultural greenhouses, and building thermal insulation materials.

[0017] Compared with the prior art, the beneficial effects of the present invention are: The present invention discloses a transparent coating film that blocks infrared rays and ultraviolet rays. The coating film is a multi-layer film structure, including a transparent base film, a coating, an adhesive, and a release film. The fluorocarbon resin and acrylic resin in the coating serve as the film-forming base, respectively enabling the coating to have extremely high weather resistance and certain hardness and wear resistance. The nano cesium tungsten bronze (Cs XTungsten trioxide (WO3) can effectively absorb infrared light and maintain a high light transmittance. The ultraviolet absorber can absorb ultraviolet light and convert it into harmless heat energy. With the help of silane coupling agent, leveling agent and defoaming agent, the adhesion of the coating can be improved, and abnormal phenomena such as horizontal and vertical streaks, shrinkage holes, and bubble points during construction can be eliminated. This coated film can effectively block infrared and ultraviolet rays while being transparent, and has excellent workability, and can be widely used in automotive glass, agricultural greenhouses and building thermal insulation materials.

[0018] 2. A transparent coated film provided by the present invention has a simple preparation process. When preparing the coating solution, nano cesium tungsten bronze (Cs X WO3) and an ultraviolet absorber are added. After curing on the surface of the substrate, a highly weather-resistant transparent coating with infrared and ultraviolet blocking properties is formed, and the coating will not affect the mechanical, optical, and thermal properties of the base film, and has excellent adhesion to the base film. In addition, this coated film also has excellent weather resistance, has a long outdoor service life, and will not have problems such as yellowing and peeling after long-term use. Brief Description of the Drawings

[0019] Figure 1 It is a schematic structural diagram of the transparent coated film in the present invention; In the figure, 1. Base film, 2. Coating, 3. Adhesive, 4. Release film. Detailed Embodiments

[0020] The present invention will be described in detail below in conjunction with the embodiments shown in the drawings. However, it should be noted that these embodiments are not limitations of the present invention, and any equivalent transformation or substitution in function, method, or structure made by those of ordinary skill in the art according to these embodiments shall fall within the protection scope of the present invention.

[0021] As Figure 1 shown, the present invention discloses a transparent coated film for blocking infrared and ultraviolet rays, its preparation method and application. The transparent coated film includes a base film 1 and a coating 2. The base film 1 itself has extremely high light transmittance and low haze. The coating solution is a transparent liquid. After curing on the surface of the base film 1, a highly weather-resistant transparent coating 2 with infrared and ultraviolet blocking properties is formed, and has good surface hardness and wear resistance, good thermal stability and weather resistance. The coating solution is cured by heating. After surface drying by heating, post-curing is carried out for a period of time. The coating 2 has good adhesion to the base film 1 and will not affect the mechanical, optical, and thermal properties of the base film 1.

[0022] The present invention discloses a transparent coated film for blocking infrared and ultraviolet rays, the transparent coated film includes a base film 1 and a coating 2; The base film 1 is made of a transparent polymer material, such as polyethylene terephthalate (PET), polycarbonate (PC), polyamide (PA), polyethylene naphthalate (PEN), or polymethyl methacrylate (PMMA), with a thickness of 50 - 200 μm, a light transmittance > 90%, and a haze < 0.5%; Above the base film 1 is a coating layer 2 with a thickness of 10 - 15 μm, and the coating layer 2 is formed by curing a coating solution.

[0023] The coating solution contains the following raw materials by mass percentage: fluorocarbon resin 28.6 - 57.2%, acrylic resin 0 - 28.6% (the sum of fluorocarbon resin and acrylic resin is 57.2%), isocyanate curing agent 5.7%, nano cesium tungsten bronze (Cs X WO3) 2 - 3%, ultraviolet absorber 2%, light stabilizer 2%, silane coupling agent 2%, leveling agent 5‰, defoaming agent 5‰, and the rest is solvent toluene or xylene.

[0024] The fluorocarbon resin is a vinyl ether - modified high - hydroxyl - value fluorocarbon resin with a hydroxyl value > 50 mgKOH / g; The acrylic resin is a high - hydroxyl - value acrylic resin with a hydroxyl value > 50 mgKOH / g; The isocyanate curing agent is an HDI trimer type; The ultraviolet absorber is a mixture of triazine - type and benzotriazole - type, and the light stabilizer is a hindered amine type.

[0025] Furthermore, the transparent coating film further includes an adhesive 3 and a release film 4; The adhesive 3 is attached to the back of the base film 1, with a light transmittance > 99% and a thickness of 10 - 50 μm. During construction, the product can be attached to the surface to be decorated through the adhesive 3; the adhesive 3 has high transparency, such as 3M8146 series, Tesa tesa 694 series, etc.; The release film 4 is attached to the adhesive 3 and is composed of PET and a transparent release layer. The surface of PET is subjected to corona or plasma treatment to make its surface dyne value ≥ 56 dyne / cm for facilitating the attachment of the release layer. The release layer is composed of a silicone oil release agent with a release force of 3 - 5 g / in. The thickness of PET is 50 - 100 μm and the thickness of the release layer is 0.1 - 0.5 μm. The release film 4 can play a protective role and is easy to operate, and can be torn off during use.

[0026] Based on the above - mentioned transparent coating film, a preparation method of the transparent coating film is obtained, including the following steps: (1) Perform corona or plasma treatment on the coating surface of the transparent substrate to make its surface dyne value ≥ 56 dyne / cm; (2) Add the isocyanate curing agent to toluene or xylene, with the addition ratio of isocyanate curing agent: solvent = 1:3 - 5 (such as mass ratios of 1:3, 1:4, 1:5, etc.). Stir with a high-speed disperser for 5 min at a rotation speed set to 500 r / min to obtain a uniformly mixed dispersion; (3) Add the ultraviolet absorber and light stabilizer to toluene or xylene, with the addition ratio of ultraviolet absorber: light stabilizer: solvent = 1:1:5 - 10 (such as mass ratios of 1:1:5, 1:1:6, 1:1:7…1:1:10, etc.). Stir with a high-speed disperser for 20 min at a rotation speed set to 2000 r / min to obtain a uniformly mixed dispersion; (4) Add nanometer cesium tungsten bronze (Cs X WO3) to toluene or xylene, introduce it into a nanometer sand mill, and grind for 4 h to obtain a uniformly mixed dispersion. The solid content of the dispersion is 20 - 30%; (5) Mix fluorocarbon resin, acrylic resin, the isocyanate curing agent dispersion in step (2), the ultraviolet absorber and light stabilizer dispersion in step (3), the nanometer cesium tungsten bronze (Cs X WO3) dispersion in step (4), silane coupling agent, leveling agent, defoaming agent and toluene or xylene in proportion. The proportion (mass percentage) is: fluorocarbon resin 28.6 - 57.2%, acrylic resin 0 - 28.6% (the sum of fluorocarbon resin and acrylic resin is 57.2%), isocyanate curing agent 5.7%, nanometer cesium tungsten bronze (Cs X WO3) 2 - 3%, ultraviolet absorber 2%, light stabilizer 2%, silane coupling agent 2%, leveling agent 5‰, defoaming agent 5‰. Stir evenly to obtain the functional coating 2 paint; (6) Uniformly coat the functional coating 2 paint on the coating surface of the transparent substrate, and obtain a highly weather-resistant transparent coating film with infrared and ultraviolet barrier properties after drying and curing; The drying and curing conditions are as follows: Put the base film coated with the coating liquid into an oven at 130 °C and keep it for 3 min to achieve surface drying, and then transfer it to an oven at 60 °C and keep it for 48 h to complete curing. (That is, the curing conditions are: 130 °C, 3 min surface drying, 60 °C, curing after 48 h) (7) Attach an adhesive 3 to the other side of the base film 1, and attach a release film 4 on the adhesive 3.

[0027] The following further elaborates on the present invention with multiple embodiments. The wavelength range of visible light is 380 nm - 780 nm, the wavelength range of infrared is 780 nm - 2500 nm, and the wavelength range of ultraviolet is 280 nm - 380 nm.

[0028] Example 1 The base film 1 is made of a PET film with a thickness of 50 μm.

[0029] The coating 2 is formed by heating and curing a coating solution, with a thickness of 10 μm. The curing conditions are surface drying at 130 °C for 3 min and post-curing at 60 °C for 48 h. The coating solution contains the following raw materials by mass percentage: fluorocarbon resin 28.6%, acrylic resin 28.6%, isocyanate curing agent 5.7%, nano cesium tungsten bronze (Cs X WO3) 2%, ultraviolet absorber 2%, light stabilizer 2%, silane coupling agent 2%, leveling agent 5‰, defoaming agent 5‰, and the rest is solvent toluene.

[0030] The fluorocarbon resin is a vinyl ether-modified high hydroxyl value fluorocarbon resin with a hydroxyl value of 56 mgKOH / g; the acrylic resin is a high hydroxyl value acrylic resin with a hydroxyl value of 60 mgKOH / g; the isocyanate curing agent is of the HDI trimer type; the ultraviolet absorber is a mixture of triazine and benzotriazole types, and the light stabilizer is a hindered amine type.

[0031] The back glue 3 has high transparency, a light transmittance of 99.1%, and a thickness of 25 μm. Then a release film 4 is laminated.

[0032] Tear off the release film 4 from the coating film prepared in this example for testing. Cross-cut test of the adhesion of coating 2: 5B; Light transmittance: 75.2%; Infrared barrier rate: 81.2%; Ultraviolet barrier rate: 99.2%.

[0033] The total irradiation dose of xenon lamp aging is 100 kwh, the adhesion of coating 2 is still 5B, there is no obvious abnormality on the surface, and its yellowing value △b = 1.79.

[0034] Example 2 Base film 1: A PEN film with a thickness of 50 μm is used.

[0035] The coating 2 is formed by heating and curing a coating solution, with a thickness of 10 μm. The curing conditions are surface drying at 130 °C for 3 min and post-curing at 60 °C for 48 h. The coating solution contains the following raw materials by mass percentage: fluorocarbon resin 38.2%, acrylic resin 19%, isocyanate curing agent 5.7%, nano cesium tungsten bronze (Cs X WO3) 3%, ultraviolet absorber 2%, light stabilizer 2%, silane coupling agent 2%, leveling agent 5‰, defoaming agent 5‰, and the rest is solvent toluene.

[0036] The fluorocarbon resin is a vinyl ether-modified high-hydroxyl-value fluorocarbon resin with a hydroxyl value of 60 mg KOH / g; the acrylic resin is a high-hydroxyl-value acrylic resin with a hydroxyl value of 56 mg KOH / g; the isocyanate curing agent is of the HDI trimer type; the ultraviolet absorber is a mixture of triazine and benzotriazole types, and the light stabilizer is a hindered amine type.

[0037] Backing adhesive 3: It has high transparency, a light transmittance of 99.1%, and a thickness of 25 μm. Then a release film 4 is laminated.

[0038] Tear off the release film 4 from the coating film prepared in this example for testing. Cross-cut test of the adhesion of coating 2: 5B; Light transmittance: 70.9%; Infrared barrier rate: 90.6%; Ultraviolet barrier rate: 99.3%; The total irradiation dose of xenon lamp aging is 100 kwh, the adhesion of coating 2 is still 5B, there is no obvious abnormality on the surface, and Δb = 1.53.

[0039] Example 3 Base film 1: A PC film with a thickness of 50 μm is used.

[0040] Coating 2 is formed by heating and curing the coating solution, with a thickness of 10 μm. The curing conditions are surface drying at 130°C for 3 minutes and post-curing at 60°C for 48 hours. The coating solution contains the following raw materials by mass percentage: fluorocarbon resin 42.9%, acrylic resin 14.3%, isocyanate curing agent 5.7%, nano-cesium tungsten bronze (Cs X WO3) 2.5%, ultraviolet absorber 2%, light stabilizer 2%, silane coupling agent 2%, leveling agent 5‰, defoaming agent 5‰, and the rest is the solvent xylene.

[0041] The fluorocarbon resin is a vinyl ether-modified high-hydroxyl-value fluorocarbon resin with a hydroxyl value of 56 mg KOH / g; the acrylic resin is a high-hydroxyl-value acrylic resin with a hydroxyl value of 60 mg KOH / g; the isocyanate curing agent is of the HDI trimer type; the ultraviolet absorber is a mixture of triazine and benzotriazole types, and the light stabilizer is a hindered amine type.

[0042] Backing adhesive 3: It has high transparency, a light transmittance of 99.1%. The thickness is 25 μm, and then a release film 4 is laminated.

[0043] Tear off the release film 4 from the coating film prepared in this example for testing. Cross-cut test of the adhesion of coating 2: 5B; Light transmittance: 72.8%; Infrared barrier rate: 84.5%; Ultraviolet blocking rate: 99.2%; The total irradiation dose of xenon lamp aging is 100 kwh. The adhesion of Coating 2 is still 5B, there is no obvious abnormality on the surface, and △b = 1.34.

[0044] Example 4 Base film 1: A PMMA film with a thickness of 50 μm is used.

[0045] Coating 2 is formed by heating and curing the coating solution, with a thickness of 10 μm. The curing conditions are 130 °C for 3 min for surface drying and 60 °C for 48 h for post-curing. The coating solution contains the following raw materials by mass percentage: fluorocarbon resin 45.8%, acrylic resin 11.4%, isocyanate curing agent 5.7%, nano cesium tungsten bronze (Cs X WO3) 2.5%, ultraviolet absorber 2%, light stabilizer 2%, silane coupling agent 2%, leveling agent 5‰, defoaming agent 5‰, and the rest is solvent xylene.

[0046] The fluorocarbon resin is a vinyl ether-modified high hydroxyl value fluorocarbon resin with a hydroxyl value of 56 mgKOH / g; the acrylic resin is a high hydroxyl value acrylic resin with a hydroxyl value of 60 mgKOH / g; the isocyanate curing agent is of the HDI trimer type; the ultraviolet absorber is a mixture of triazine and benzotriazole types, and the light stabilizer is a hindered amine type.

[0047] Back glue 3: It has high transparency, and the light transmittance is 99.1%. The thickness is 25 μm, and a release film 4 is laminated.

[0048] Tear off the release film 4 of the coating film prepared in this example for testing; Cross-cut test of the adhesion of Coating 2: 5B; Light transmittance: 72.6%; Infrared blocking rate: 85.6%; Ultraviolet blocking rate: 99.3%; The total irradiation dose of xenon lamp aging is 100 kwh. The adhesion of Coating 2 is still 5B, there is no obvious abnormality on the surface, and △b = 1.28.

[0049] Example 5 Base film 1: A PA film with a thickness of 75 μm is used.

[0050] Coating 2 is formed by heating and curing the coating solution, with a thickness of 15 μm. The curing conditions are 130 °C for 3 min for surface drying and 60 °C for 48 h for post-curing. The coating solution contains the following raw materials by mass percentage: fluorocarbon resin 38.2%, acrylic resin 19%, isocyanate curing agent 5.7%, nano cesium tungsten bronze (Cs X2.2% of WO3, 2% of ultraviolet absorber, 2% of light stabilizer, 2% of silane coupling agent, 5‰ of leveling agent, 5‰ of defoaming agent, and the rest is solvent toluene.

[0051] The fluorocarbon resin is a vinyl ether modified high hydroxyl value fluorocarbon resin with a hydroxyl value of 56mgKOH / g; the acrylic resin is a high hydroxyl value acrylic resin with a hydroxyl value of 60mgKOH / g; the isocyanate curing agent is of the HDI trimer type; the ultraviolet absorber is a mixture of triazine and benzotriazole types, and the light stabilizer is a hindered amine type.

[0052] Back glue 3: It has high transparency, with a light transmittance of 99.1%. The thickness is 25um, and a release film 4 is laminated on it.

[0053] Tear off the release film 4 from the coating film prepared in this example for testing; Cross-cut test of the adhesion of coating 2: 5B; Light transmittance: 73.6%; Infrared barrier rate: 82.1%; Ultraviolet barrier rate: 99.5%; The total irradiation dose of xenon lamp aging is 100kwh, the adhesion of coating 2 is still 5B, there is no obvious abnormality on the surface, and △b = 1.65.

[0054] Example 6 Base film 1: Use a PET film with a thickness of 50 um.

[0055] Coating 2 is formed by heating and curing the coating liquid, with a thickness of 12.5um. The curing conditions are surface drying at 130°C for 3min and post-curing at 60°C for 48h. The coating liquid contains the following raw materials by mass percentage: 57.2% of fluorocarbon resin, 5.7% of isocyanate curing agent, nano cesium tungsten bronze (Cs X WO3) 2%, 2% of ultraviolet absorber, 2% of light stabilizer, 2% of silane coupling agent, 5‰ of leveling agent, 5‰ of defoaming agent, and the rest is solvent toluene.

[0056] The fluorocarbon resin is a vinyl ether modified high hydroxyl value fluorocarbon resin with a hydroxyl value of 56mgKOH / g; the isocyanate curing agent is of the HDI trimer type; the ultraviolet absorber is a mixture of triazine and benzotriazole types, and the light stabilizer is a hindered amine type.

[0057] Back glue 3: It has high transparency, with a light transmittance of 99.1%. The thickness is 50um, and a release film 4 is laminated on it.

[0058] Tear off the release film 4 from the coating film prepared in this example for testing; Cross-cut test of the adhesion of coating 2: 5B; Light transmittance: 73.6%; Infrared blocking rate: 83.1%; Ultraviolet blocking rate: 99.4%; The total irradiation dose of xenon lamp aging is 100 kwh, the adhesion of the coating 2 is still 5B, there is no obvious abnormality on the surface, and △b = 0.75.

[0059] Comparative example: A common high-end decorative film for the front windshield of a car on the market has a visible light transmittance of 75.6%, an infrared blocking rate of 80.9%, and an ultraviolet blocking rate of 99.1%. The total irradiation dose of xenon lamp aging is 100 kwh, and the appearance has changed greatly, with some cracking, some powdering, a large yellowing value, and △b = 6.35.

[0060] In summary, from the relevant data of the above examples and comparative examples, it can be seen that the transparent coating film provided by the present invention has a quite high infrared blocking rate and ultraviolet blocking rate, and has excellent aging resistance. After xenon lamp irradiation, problems such as yellowing and peeling will not occur. In addition, when preparing, fluorocarbon resin and acrylic resin are used as raw materials, which can not only improve the transparency of the film, but also increase the toughness and wear resistance of the coating film, and has good stability in various environments. It can be widely used in fields such as automotive glass, agricultural greenhouses, and building thermal insulation materials.

[0061] The transparent coating film provided by the present invention solves the problems that the common functional films on the current market only have the function of ultraviolet blocking or infrared reflection, and have poor weather resistance, and are prone to problems such as yellowing and peeling after long-term use, and has good application prospects and high economic value.

[0062] 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 transparent coating film for blocking infrared rays and ultraviolet rays, the coating film comprising a base film and a coating layer attached to the front side of the base film, characterized in that: The base film is made of polymer material, with a thickness of 50-200μm, a light transmittance of more than 90%, and a haze of less than 0.5%; The coating has a thickness of 10-15 μm. The raw materials for preparing the coating include the following components (by mass percentage): 28.6-57.2% fluorocarbon resin, 0-28.6% acrylic resin (the sum of fluorocarbon resin and acrylic resin is 57.2%), 5.7% isocyanate curing agent, and nano cesium tungsten bronze (Cs X WO3) 2-3%, UV absorber 2%, light stabilizer 2%, silane coupling agent 2%, leveling agent 5‰, defoamer 5‰, and the rest is solvent toluene or xylene; Also includes, Adhesive, attached to the back of the base film, with a light transmittance of >99% and a thickness of 10-50μm; The release film is attached to the backing adhesive and is composed of PET and a transparent release layer. The release layer is made of a silicone oil release agent with a release force of 3-5g / in. The thickness of PET is 50-100um and the thickness of the release layer is 0.1-0.5um.

2. The transparent coating film for blocking infrared and ultraviolet rays according to claim 1, characterized in that: The fluorocarbon resin is a vinyl ether modified fluorocarbon resin with a high hydroxyl value, and the hydroxyl value is greater than 50 mgKOH / g.

3. The transparent coating film for blocking infrared rays and ultraviolet rays according to claim 1, characterized in that: The acrylic resin is a high hydroxyl value acrylic resin, and the hydroxyl value is greater than 50 mgKOH / g.

4. The transparent coating film for blocking infrared rays and ultraviolet rays according to claim 1, characterized in that: The isocyanate curing agent is of HDI trimer type.

5. The transparent coating film for blocking infrared rays and ultraviolet rays according to claim 1, characterized in that: The ultraviolet absorber is a mixed type of triazines and benzotriazoles, and the light stabilizer is hindered ammonia.

6. The transparent coating film for blocking infrared rays and ultraviolet rays according to claim 1, characterized in that: The base film is any one of polyethylene terephthalate (PET), polycarbonate (PC), polyamide (PA), polyethylene naphthalate (PEN) or polymethyl methacrylate (PMMA).

7. A method for preparing a transparent coating film for blocking infrared and ultraviolet rays as claimed in any one of claims 1 to 6, comprising the following steps: (1) Treat the coated surface of the transparent substrate with corona or plasma to make its surface dyne value ≥56 dyne / cm and keep it for future use; (2) Adding isocyanate curing agent to toluene or xylene in a ratio of isocyanate curing agent: solvent = 1:3–5 (mass ratio), stirring with a high-speed disperser for 5 min at a speed of 500 r / min to obtain a uniformly mixed dispersion; (3) Adding the ultraviolet absorber and the light stabilizer to toluene or xylene in a ratio of ultraviolet absorber: light stabilizer: solvent = 1:1:5-10 (mass ratio), stirring with a high-speed disperser for 20 minutes at a speed of 2000 r / min to obtain a uniformly mixed dispersion; (4) Nano cesium tungsten bronze (Cs X WO3) is added to toluene or xylene, introduced into a nano sand mill, and ground for 4 hours to obtain a uniformly mixed dispersion with a solid content of 20-30%; (5) Fluorocarbon resin, acrylic resin, isocyanate curing agent dispersion in step (2), ultraviolet absorber and light stabilizer dispersion in step (3), nano cesium tungsten bronze (Cs X WO3) dispersion, silane coupling agent, leveling agent, defoamer and toluene or xylene are mixed in proportion, and the proportion (mass percentage) is: fluorocarbon resin 28.6-57.2%, acrylic resin 0-28.6% (the sum of fluorocarbon resin and acrylic resin is 57.2%), isocyanate curing agent 5.7%, nano cesium tungsten bronze (Cs X WO3) 2-3%, UV absorber 2%, light stabilizer 2%, silane coupling agent 2%, leveling agent 5‰, defoamer 5‰, and the rest are solvent toluene or xylene, and stir evenly to obtain a functional coating; (6) uniformly coating the functional coating on the coating surface of the transparent substrate, and drying and curing the coating to obtain a highly weather-resistant transparent coating film with infrared and ultraviolet blocking properties; (7) Attach a backing adhesive to the other side of the base film, and then attach a layer of release film to the backing adhesive.

8. According to the method for preparing a transparent coating film that blocks infrared and ultraviolet rays as described in claim 7, in step (6), the drying and curing conditions are: placing the base film coated with the coating liquid in an oven at 130°C for 3 minutes to achieve surface drying, and then transferring it to an oven at 60°C and keeping it for 48 hours to cure.

9. Use of the transparent coating film for blocking infrared and ultraviolet rays as claimed in any one of claims 1 to 6 in the preparation of automobile glass, agricultural greenhouses, and building insulation materials.

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