A color-changing film composite structure and preparation method thereof

Abstract

The present invention relates to a color-changing thin film composite structure and its preparation method. The color-changing thin film composite structure comprises a glass layer, an adhesion layer, a base layer, a color-changing light-reflecting layer, and a protective layer stacked in sequence. The adhesion layer comprises a coupling agent having a first functional group. The base layer is formed by polymerizing a polymerizable raw material. The polymerizable raw material comprises a reactant having a second functional group, and the first functional group can react with the second functional group to form a chemical bond. The color-changing thin film composite structure can improve the adhesion of the color-changing film to glass and is flexible for application to glass of different shapes.

Description

Technical Field

[0001] The present invention relates to the field of materials, and in particular to a color-changing thin film composite structure and a preparation method thereof. Background Art

[0002] With the rapid advancement of technology, glass plays an increasingly important role in our daily lives. Not only does it provide unparalleled transparency, but its aesthetic and practicality have also led to its widespread use in architecture, automobiles, and various consumer products. However, the widespread use of glass also brings with it issues such as reduced privacy and increased external heat radiation. To address these issues, color-shifting film technology has been developed. Color-shifting film is a high-tech material that responds to external stimuli such as heat, light, and electricity. This film automatically adjusts its color, transmittance, and haze according to changes in the external environment, thereby enabling intelligent control of light and vision. Color-shifting film technology is primarily applied through glass coating, glass lamination, or laminated glass. These methods impose strict requirements on glass size, curvature, and hyperbolic curvature, limiting its application to certain glass shapes. This issue is particularly prominent in the design of new energy vehicle sunroofs. Due to the complex hyperbolic structure of automotive sunroofs, traditional dimming and color-shifting films present significant challenges in bonding. Furthermore, existing color-shifting films also suffer from poor adhesion to glass. Summary of the Invention

[0003] In view of the deficiencies of the prior art, the first object of the present invention is to provide a color-changing film composite structure, which can improve the adhesion of the color-changing film to the glass and is flexible in application to glass of different shapes.

[0004] The second object of the present invention is to provide a method for preparing the above-mentioned color-changing thin film composite structure.

[0005] To achieve the first purpose of the present invention, the present invention provides a color-changing thin film composite structure, which includes a glass layer, an adhesion layer, a base layer, a color-changing light-emitting layer and a protective layer stacked in sequence, the adhesion layer includes a coupling agent having a first functional group, the base layer is formed by polymerization of a polymerizable raw material, the polymerizable raw material includes a reactant having a second functional group, and the first functional group can react with the second functional group to form a chemical bond.

[0006] In some embodiments of the present invention, the color-changing light-emitting layer includes a first conductive layer, an electrically responsive color-changing light-emitting layer, and a second conductive layer. The first conductive layer is connected to the base layer, and the second conductive layer is connected to the protective layer.

[0007] In some embodiments of the present invention, the first functional group and the second functional group are each an alkenyl group.

[0008] In some embodiments of the present invention, one of the first functional group and the second functional group is at least one of an epoxy group and an isocyanate group, and the other is at least one of an amino group, a carboxyl group, a hydroxyl group, and a thiol group.

[0009] In some embodiments of the present invention, the coupling agent is at least one of a silane coupling agent, a titanate coupling agent, and a phosphate coupling agent; and the polymerizable raw material includes at least one of a photocurable resin and a thermosetting resin.

[0010] In some embodiments of the present invention, the coupling agent having a first functional group is a silane coupling agent having a double bond, and the silane coupling agent is at least one of vinyltrimethoxysilane and vinyltriethoxysilane.

[0011] In some embodiments of the present invention, the reactant having the second functional group is at least one of an acrylic epoxy resin and an acrylic resin.

[0012] In some embodiments of the present invention, the protective layer includes at least one of a photocurable resin and a thermosetting resin; the protective layer is at least one of a silicone coating, a polyurethane coating, and an acrylic coating; the protective layer contains a low surface energy reactant, a toughening reactant, and a multifunctional reactant.

[0013] In some embodiments of the present invention, at least a portion of the surface of the glass layer in contact with the base layer is a curved surface or a special-shaped surface.

[0014] In some embodiments of the present invention, the first conductive layer and the second conductive layer are respectively made of conductive paste, and the conductive paste is at least one of nano silver paste and PEDOT:PSS paste.

[0015] In some embodiments of the present invention, the electrically responsive color-changing light-emitting layer is at least one of PDLC and EC.

[0016] In some embodiments of the present invention, the PDLC comprises a mixture of glue and nematic liquid crystal, the glue is at least one of a light-curing resin and a heat-curing resin, the glue is an acrylate glue, the acrylate glue comprises at least one of polyalkyl acrylate bornyl, methacrylate, acrylate isobornyl, methacrylate-2-hydroxyethyl, isobornyl methacrylate, and hydroxyalkyl methacrylate, the nematic liquid crystal comprises trans-4-(4-propylcyclohexane)-1,2-dimethyl-1-[ ... At least one of: 1,2-difluoro-4-[2-[(trans,trans)-4'-propyl[1,1'-bicyclohexyl]-4-yl]ethyl]-benzene, and 4-(5-butyl-2-pyrimidinyl)benzonitrile.

[0017] In some embodiments of the present invention, the EC includes a diluent and a color-changing material, the diluent includes at least one of methyl methacrylate and cyclotrimethylolpropane formal acrylate, and the color-changing material includes at least one of a p-phenylenediamine derivative, benzoquinone, ethoxyanthraquinone, imidazolylbenzoquinone, a thermosensitive black derivative, lithium perchlorate, and tetrabutylammonium hexafluorophosphate.

[0018] In some embodiments of the present invention, the thickness of the adhesion layer is 5 to 10 μm; the thickness of the base layer is 5 to 25 μm; the thickness of the first conductive layer is 10 to 15 μm; the thickness of the electrically responsive color-changing light-emitting layer is 10 to 80 μm; the thickness of the second conductive layer is 10 to 15 μm; and the thickness of the protective layer is 30 to 50 μm.

[0019] To achieve the second purpose of the present invention, the present invention provides a method for preparing a color-changing thin film composite structure, which includes: coating the adhesion layer, the base layer, the color-changing light-emitting layer and the protective layer on the glass layer in sequence.

[0020] In some embodiments of the present invention, the color-changing light-emitting layer includes a first conductive layer, an electrically responsive color-changing light-emitting layer, and a second conductive layer, and the preparation method includes:

[0021] Step 1: spraying or applying the adhesive layer on the glass layer;

[0022] Step 2: spraying or applying the slurry of the base layer to the adhesive layer, and then curing;

[0023] Step 3: spraying or applying the slurry of the first conductive layer onto the base layer, and then baking;

[0024] Step 4: spraying or applying the slurry of the electrically responsive color-changing light-emitting layer on the first conductive layer, and then curing it;

[0025] Step 5: spraying or applying the slurry of the second conductive layer to the electrically responsive color-changing light-emitting layer, and then baking;

[0026] Step six: spray or apply the slurry of the protective layer to the second conductive layer, and then cure it.

[0027] In some embodiments of the present invention, in steps 1 to 6, a spraying process is adopted to adjust the discharge speed and the movement speed of the spray gun to control the thickness of each layer.

[0028] In some embodiments of the present invention, the base layer, the electrically responsive color-changing light-emitting layer, and the protective layer respectively contain photocurable resins, and the curing in steps 2, 4, and 6 is UV light curing.

[0029] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0030] The color-changing film composite structure of the present invention is a glass layer in which an adhesion layer, a base layer, a color-changing light-emitting layer and a protective layer are sequentially stacked, wherein the adhesion layer includes a coupling agent having a first functional group, one end of the coupling agent is connected to the glass, and the first functional group at the other end reacts with the second functional group in the base layer to form a chemical bond, thereby making the base layer firmly attached to the glass layer, that is, making the color-changing film formed by the base layer, the color-changing light-emitting layer and the protective layer firmly attached to the glass as a whole, thereby improving the overall adhesion of the film layer, and making the color-changing film as a whole able to be attached to glass layers of different shapes, such as curved glass, so that the application of the color-changing film is more flexible and has strong applicability.

[0031] In addition, the present invention also provides a method for preparing the color-changing thin film composite structure, which adopts a step-by-step film formation method on the glass layer to layer-process the adhesion layer, base layer, color-changing light-emitting layer and protective layer, and can further improve the adhesion between the layers, so that each layer can better adapt to different glass shapes. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a structural schematic diagram of an embodiment of the color-changing thin film composite structure of the present invention.

[0033] In the figure, 1 is a glass layer, 2 is an adhesive layer, 3 is a base layer, 4 is a first conductive layer, 5 is an electrically responsive color-changing light-emitting layer, 6 is a second conductive layer, and 7 is a protective layer.

[0034] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. DETAILED DESCRIPTION

[0035] The present invention provides an embodiment of a color-changing film composite structure. This composite structure, comprising glass and a color-changing film, can be used in applications involving glass, such as architecture, automobiles, and various consumer products, and is particularly suitable for applications involving curved glass. This color-changing film composite structure can impart color-changing light-transmitting properties to the glass, for example, through thermochromism or electrochromism, causing the light passing through the glass to change.

[0036] Specifically, the color-changing film composite structure of this embodiment includes a glass layer 1, an adhesion layer 2, a base layer 3, a color-changing dimming layer, and a protective layer 7 stacked in sequence. The adhesion layer 2 includes a coupling agent having a first functional group. The base layer 3 is formed by polymerizing a polymerizable raw material. The polymerizable raw material includes a reactant having a second functional group, and the first functional group can react with the second functional group to form a chemical bond. It can be seen that in the color-changing film composite structure of this embodiment, the adhesion layer 2 uses a coupling agent, one end of the coupling agent is tightly connected to the glass layer, and the other end has a first functional group. The coupling agent in the adhesion layer 2 and the polymerizable raw material in the base layer 3 form a strong chemical bond through the chemical reaction of the first functional group and the second functional group, thereby improving the bonding strength between the adhesion layer 2 and the base layer 3. The base layer 3 serves as the base of the color-changing dimming layer. The color-changing dimming layer forms a sandwich structure of the dimming film between the base layer 3 and the protective layer 7. The use of the above-mentioned color-changing film composite structure can improve the adhesion between the glass and the dimming film as a whole, making the dimming film as a whole suitable for glass of different shapes.

[0037] Compared to existing techniques that adhere prepared color-shifting films, such as laminated color-shifting films, to glass using adhesives, this embodiment reduces the requirements for application size and curvature, broadens the application scenarios of the dimming color-shifting film, and offers greater flexibility and adaptability, better meeting the needs of color-shifting films for glass or special-shaped surfaces. This embodiment uses a coupling agent to improve the adhesion between the base layer and the glass, reducing the number of structural layers in the product.

[0038] In some examples, the color-changing thin film composite structure of this embodiment is composed of a glass layer 1, an adhesion layer 2, a base layer 3, a color-changing light-emitting layer and a protective layer 7 stacked in sequence. The color-changing thin film composite structure does not contain any other layered structures except the glass layer 1, the adhesion layer 2, the base layer 3, the color-changing light-emitting layer and the protective layer 7.

[0039] In some examples, the glass layer 1 can be an existing glass, such as silicate glass such as soda lime silicate, soda aluminum silicate, and soda borosilicate glass. This embodiment is also applicable to various types of glass. The coupling agent with a first functional group in the adhesion layer 2 can be an existing coupling agent, wherein a coupling agent in the art generally refers to a compound containing two groups with different chemical properties, one of the two groups is an inorganic-philic group that can chemically react with the glass layer, allowing the coupling agent to be tightly bonded to the glass. The other group, i.e., the first functional group, is an organic-philic group that can chemically react with the second functional group of the base layer 3, thereby firmly connecting the base layer 3 and the glass layer 1. The base layer 3 and the protective layer 7 sandwich the color-changing light-transmitting layer, jointly providing support for the color-changing light-transmitting layer, and the protective layer 7 also provides good protection for the outer side of the color-changing light-transmitting layer.

[0040] In some examples, the chemical bond formed by the first functional group and the second functional group can be an ionic bond, a covalent bond, a coordination bond, etc. For example, the chemical bond can be a covalent bond, which has high stability.

[0041] In some examples, the color-changing light-emitting layer includes a first conductive layer 4, an electrically responsive color-changing light-emitting layer 5, and a second conductive layer 6. The first conductive layer 4 is connected to the base layer 3, and the second conductive layer 6 is connected to the protective layer 7, thereby obtaining an electrochromic color-changing light-emitting layer. When the power is on and off, the color-changing thin film composite structure can have different visible light transmittances, thereby realizing the dimming function.

[0042] In some examples, the color-changing light-emitting layer is composed of a first conductive layer 4 , an electrically responsive color-changing light-emitting layer 5 , and a second conductive layer 6 , and the color-changing light-emitting layer does not contain any other layered structures except the first conductive layer 4 , the electrically responsive color-changing light-emitting layer 5 , and the second conductive layer 6 .

[0043] In other examples, the color-changing light-emitting layer may also be an existing thermochromic material to achieve a thermochromic function. The thermochromic material may include, for example, a thermochromic organic material such as a liquid crystal material, a thermochromic inorganic material, and the like.

[0044] In some examples, the first functional group and the second functional group are alkenyl groups, respectively. The alkenyl groups of the first functional group and the second functional group are copolymerized to achieve a chemical reaction between the first functional group and the second functional group and form a covalent bond.

[0045] In other examples, one of the first functional group and the second functional group is at least one of an epoxy group and an isocyanate group, and the other is at least one of an amino group, a carboxyl group, a hydroxyl group, and a thiol group. A covalent bond is formed by a chemical reaction between the epoxy group or the isocyanate group and the active hydrogen to achieve a tight connection between the adhesion layer and the base layer.

[0046] In some examples, the coupling agent in the adhesion layer 2 is at least one of a silane coupling agent, a titanate coupling agent, and a phosphate coupling agent. The raw materials of these coupling agents are readily available and can chemically react with glass to form a tight bond with the glass. For example, the siloxane groups or silanol groups in the silane coupling agent can undergo a dehydration reaction with hydroxyl groups on the glass to form Si—O—Si bonds.

[0047] In some examples, the polymerizable material of the base layer 3 includes at least one of a photocurable resin and a thermosetting resin. The polymerizable material can be coated on the adhesion layer 2 and then cured by light or heat to form a film.

[0048] In some examples, the coupling agent having a first functional group is a silane coupling agent having a double bond, for example, the silane coupling agent is at least one of vinyltrimethoxysilane and vinyltriethoxysilane, and the double bond in the silane coupling agent having a double bond is the first functional group, and the double bond can directly react with the resin of the base layer 3, for example, participate in the polymerization of the resin of the base layer 3.

[0049] In some examples, the reactant having a second functional group is at least one of an acrylic epoxy resin and an acrylic resin. The above resin has an allyl group and can copolymerize with the double bond on the silane coupling agent. After the resin is polymerized, it can form a thin film with a certain hardness and strength, constituting the base layer 3, providing support for the color-changing light-emitting layer.

[0050] In some examples, the protective layer 7 includes at least one of a photocurable resin and a thermosetting resin. The protective layer 7 can be applied to the color-changing light-emitting layer and then cured by light or heat to form a film. The protective layer 7 can be at least one of a silicone coating, a polyurethane coating, and an acrylic coating. These coatings have advantages such as readily available raw materials and easy film formation. In some examples, the protective layer 7 contains a low-surface-energy reactant, a toughening reactant, and a multifunctional reactant. The low-surface-energy reactant can impart anti-fouling and dust-proof properties to the protective layer 7. The toughening reactant can increase the toughness of the protective layer 7, making it wear-resistant and scratch-resistant. The multifunctional reactant can increase the strength and hardness of the protective layer 7. The protective layer 7 may also contain additives such as initiators, diluents, leveling agents, and defoaming agents.

[0051] In some examples, at least a portion of the surface of the glass layer 1 in contact with the base layer 2 is a curved or shaped surface, such as a curved surface, a bent surface, or a combination thereof. The color-shifting light-emitting film comprising the base layer 2 can be applied to a glass layer 1 having a curved or shaped surface. For example, the glass layer 1 can be a double-curved glass.

[0052] In some examples, the first conductive layer 4 and the second conductive layer 6 are each made of a conductive paste. The conductive paste can be applied to adjacent layer structures and dried and cured to form the conductive layer. The conductive paste can be at least one of a nanosilver paste and a PEDOT:PSS paste, as long as it can achieve a conductive function.

[0053] In some examples, the electrically responsive color-changing light-emitting layer 5 is at least one of PDLC and EC. PDLC is a polymer dispersed liquid crystal material, and EC is an electrochromic material. In this embodiment, PDLC and EC can each be made of existing materials.

[0054] In some examples, the PDLC comprises a mixture of glue and nematic liquid crystals. Nematic liquid crystals can align in an ordered or disordered manner under the influence of an electric field, causing changes in visible light transmittance, thereby achieving electrochromic control. The glue is used to disperse the nematic liquid crystals, stabilizing the PDLC structure. The glue is at least one of a photocurable resin and a thermosetting resin, capable of curing by light or heat to produce a structurally stable PDLC. In some examples, the glue is an acrylate glue, comprising at least one of polyalkyl bornyl acrylate, methacrylate, isobornyl acrylate, 2-hydroxyethyl methacrylate, isobornyl methacrylate, and hydroxyalkyl methacrylate. These (meth)acrylate monomers can polymerize and disperse the liquid crystals into small units. The glue may also contain additives such as initiators, diluents, leveling agents, and defoamers. The nematic liquid crystal includes at least one of trans-4-(4-propylcyclohexyl)benzonitrile, pentylbiscyclohexylethane, 4'-n-pentyl-4-cyanobiphenyl, vinylbiscycloethyl 3,4-difluorobenzene, trans-(4-propylcyclohexyl)cyclohexanecarboxylic acid-4-(trans-4-propylcyclohexyl)phenyl ester, 4'-propyl-4-ethoxytoluene, 1,2-difluoro-4-[2-[(trans, trans)-4'-propyl[1,1'-biscyclohexyl]-4-yl]ethyl]-benzene, and 4-(5-butyl-2-pyrimidinyl)benzonitrile. The nematic liquid crystal can undergo orientation changes under an electric field.

[0055] In some examples, the EC includes a diluent and a color-changing material. The diluent includes at least one of methyl methacrylate and cyclotrimethylolpropane formal acrylate, and the diluent is capable of curing and dispersing the color-changing material. The diluent may also contain additives such as initiators, diluents, leveling agents, and defoamers. The color-changing material may include at least one of a p-phenylenediamine derivative, benzoquinone, ethoxyanthraquinone, imidazolylbenzoquinone, a thermosensitive black derivative, lithium perchlorate, and tetrabutylammonium hexafluorophosphate. These color-changing materials are capable of undergoing molecular isomerization and electron transfer under an electric field, thereby achieving electrochromism.

[0056] In some examples, the thickness of the adhesion layer is 5 to 10 μm. In some examples, the thickness of the base layer is 5 to 25 μm. In some examples, the thickness of the first conductive layer is 10 to 15 μm. In some examples, the thickness of the electrochromic color-changing light-emitting layer is 10 to 80 μm. In some examples, the thickness of the second conductive layer is 10 to 15 μm. In some examples, the thickness of the protective layer is 30 to 50 μm. The above-mentioned layered structure has a smaller thickness, which can reduce the overall thickness of the color-changing film, thereby reducing the product size while achieving electrochromic and protective functions.

[0057] In some examples, the method for preparing the color-changing thin film composite structure of any of the above-described solutions includes sequentially coating an adhesion layer 2, a base layer 3, a color-changing light-emitting layer, and a protective layer 7 on a glass layer 1. This embodiment utilizes a layer-by-layer coating and film-forming method to achieve copolymerization of the first functional group of the adhesion layer 2 with the base layer 3, thereby improving adhesion and ensuring a tight bond between the layers, so that each layer better matches the shape of the glass layer 1.

[0058] In some examples, the color-shifting light-emitting layer includes a first conductive layer 4, an electrically responsive color-shifting light-emitting layer 5, and a second conductive layer 6. The preparation method includes the following steps: Step 1: spraying or applying an adhesion layer 2 on a glass layer 1; Step 2: spraying or applying a slurry of a base layer 3 on the adhesion layer 2, and then curing; Step 3: spraying or applying a slurry of a first conductive layer 4 on the base layer 3, and then baking; Step 4: spraying or applying a slurry of a electrically responsive color-shifting light-emitting layer 5 on the first conductive layer 4, and then curing; Step 5: spraying or applying a slurry of a second conductive layer 6 on the electrically responsive color-shifting light-emitting layer 5, and then baking; Step 6: spraying or applying a slurry of a protective layer 7 on the second conductive layer 6, and then curing. It can be seen that in this embodiment, the adhesion layer 2, base layer 3, first conductive layer 4, electrically responsive color-shifting light-emitting layer 5, second conductive layer 6, and protective layer 7 are sequentially formed on the glass layer 1.

[0059] In some examples, in steps one to six, a spraying process is used to adjust the discharge speed and the movement speed of the spray gun to control the thickness of each layer, which is conducive to precise control of the thickness.

[0060] In some examples, the base layer, the electro-responsive color-changing light-emitting layer, and the protective layer each contain a light-curable resin, and the curing in steps 2, 4, and 6 is performed by UV light irradiation. Light curing has the advantages of low curing temperature and fast curing speed.

[0061] Example 1

[0062] The preparation steps of this embodiment are as follows:

[0063] S1: Spray vinyl trimethoxysilane, a silane coupling agent with double bonds, on the glass surface, adjust the discharge speed and the movement speed of the spray gun, and control the spray thickness to 10 microns.

[0064] S2: 30% by mass of polyurethane modified acrylate, 20% by mass of hexyl ester acrylate, 48% by mass of dipentaerythritol pentaacrylate, 1% by mass of 2-hydroxy-2-methyl-1-phenylpropanone, and 1% by mass of 1-hydroxycyclohexyl phenyl ketone were uniformly mixed to prepare a base layer slurry.

[0065] S3: Spray the base layer slurry onto the glass surface treated with silane coupling agent with a thickness of 25 microns. After spraying, irradiate with UV light with an energy of 1000 mJ / cm 2 The base layer can be prepared as described above. The double bonds in the silane coupling agent will directly participate in the polymerization reaction of the base layer to improve the overall adhesion.

[0066] S4: 90% by mass of the nano silver wire dispersion (silver wire mass fraction 0.5%) and 10% of hydroxypropyl methylcellulose were uniformly mixed to prepare the nano silver wire slurry.

[0067] S5: Spray the silver nanowire slurry evenly on the surface of the base layer with a thickness of 15 μm. After completion, bake at 100° C. for 300 seconds to obtain the first conductive layer.

[0068] S6: 60% by mass of liquid crystal A (including 50% by mass of 4'-n-pentyl-4-cyanobiphenyl, 15% by mass of vinylbiscycloethyl 3,4-difluorobenzene, 15% by mass of 1,2-difluoro-4-[2-[(trans,trans)-4'-propyl[1,1'-bicyclohexyl]-4-yl]ethyl]-benzene and 20% by mass of trans-(4-propylcyclohexyl)cyclohexanecarboxylic acid-4-(trans-4-propylcyclohexyl)phenyl ester) and 40% by mass of glue (including 40% by mass of isobornyl methacrylate, 30% by mass of 2-hydroxyethyl methacrylate, 28% by mass of isobornyl acrylate and 2% by mass of 2,4,6-(trimethylbenzoyl)diphenylphosphine oxide) are mixed evenly to prepare an electrically responsive slurry.

[0069] S7: Spray the electroresponsive slurry evenly on the surface of the nanosilver conductive layer with a thickness of 20 microns. After completion, irradiate with UV light with an energy of 3000mJ / cm 2 The above steps can form an electric response film layer.

[0070] S8: Spray a 1.5% by mass PEDOT:PSS slurry evenly onto the surface of the electroresponsive film layer to a thickness of 15 μm. After completion, bake at 120°C for 300 seconds to obtain a second conductive layer.

[0071] S9: 4% by mass of fluoro-silicone grafted polymer, 25% by mass of polyurethane acrylate, 40% by mass of dipentaerythritol acrylate, 24% by mass of cyclohexane, and 7% by mass of photoinitiator 1173 were uniformly mixed to prepare a high-hardness surface base slurry.

[0072] S10: Spray the high-hardness surface base slurry evenly on the surface of the electro-responsive coating, with a thickness of 50 microns. After completion, irradiate with UV light, and the energy reaches 2000mJ / cm 2 The above can form a high hardness surface base layer.

[0073] Example 2

[0074] The preparation steps of this embodiment are as follows:

[0075] S1: spraying vinyltrimethoxysilane, a silane coupling agent with double bonds, on the same glass surface as in Example 1, adjusting the discharge speed and the movement speed of the spray gun to control the spraying thickness to 5 μm.

[0076] S2: 30% by mass of polyurethane modified acrylate, 20% by mass of hexyl ester acrylate, 48% by mass of dipentaerythritol pentaacrylate, 1% by mass of 2-hydroxy-2-methyl-1-phenylpropanone, and 1% by mass of 1-hydroxycyclohexyl phenyl ketone were uniformly mixed to prepare a base layer slurry.

[0077] S3: Spray the base layer slurry onto the glass surface treated with silane coupling agent with a thickness of 10 microns. After spraying, irradiate with UV light with an energy of 800mJ / cm 2 The base layer can be prepared as described above. The double bonds in the silane coupling agent will directly participate in the polymerization reaction of the base layer to improve the overall adhesion.

[0078] S4: 90% by mass of the nano silver wire dispersion (silver wire mass fraction 0.5%) and 10% of hydroxypropyl methylcellulose were uniformly mixed to prepare the nano silver wire slurry.

[0079] S5: Spray the silver nanowire slurry evenly on the surface of the base layer with a thickness of 10 μm. After completion, bake at 100° C. for 250 seconds to obtain the first conductive layer.

[0080] S6: 50% by mass of the color-changing material ethoxyanthraquinone and 50% of the diluent (containing 60% by mass of methyl methacrylate, 39% by mass of cyclotrimethylolpropane formal acrylate and 1% by mass of 2-hydroxy-2-methyl-1-phenylacetone) were mixed uniformly to prepare an electroresponsive slurry.

[0081] S7: Spray the electroresponsive slurry evenly on the surface of the nanosilver conductive layer with a thickness of 30 microns. After completion, irradiate with UV light with an energy of 2000mJ / cm 2 The above steps can form an electric response film layer.

[0082] S8: Spray a 1.5% by mass PEDOT:PSS slurry evenly onto the surface of the electroresponsive film layer to a thickness of 10 μm. After completion, bake at 120°C for 250 seconds to obtain a second conductive layer.

[0083] S9: 4% by mass of fluoro-silicone grafted polymer, 25% by mass of polyurethane acrylate, 40% by mass of dipentaerythritol acrylate, 24% by mass of cyclohexane, and 7% by mass of photoinitiator 1173 were uniformly mixed to prepare a high-hardness surface base slurry.

[0084] S10: Spray the high-hardness surface base slurry evenly on the surface of the electro-responsive coating, with a thickness of 30 microns. After completion, irradiate with UV light, and the energy reaches 1800mJ / cm 2 The above can form a high hardness surface base layer.

[0085] Comparative Example 1

[0086] The silane coupling agent in Example 1 was replaced with KH550 (γ-aminopropyltriethoxysilane). Other steps were the same as in Example 1.

[0087] Referring to the cross-cut test requirements for paint and varnish films in GB / T 9286-1998, three test areas were cut into the film using a crosshatch knife. A peel test was then conducted using tape with an adhesion strength of 10 N / 25 mm. In the color-changing film composite structures of Examples 1 and 2, there was no noticeable separation between the substrate and glass layers, while in Comparative Example 1, there was significant separation between the substrate and glass layers. This indicates that the silane coupling agent in Comparative Example 1 only improves adhesion to the glass surface through silane-oxygen bonds, without enhancing adhesion between the substrate and the silane coupling agent.

[0088] Finally, it should be emphasized that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of protection of the present invention.

Claims

1. A method for preparing a color-changing thin film composite structure, characterized in that The color-changing thin film composite structure includes a glass layer, an adhesive layer, a base layer, a color-changing light-emitting layer, and a protective layer stacked in sequence. The surface of the glass layer in contact with the base layer is at least partially a curved or profiled surface. The color-changing light-emitting layer includes a first conductive layer, an electrically responsive color-changing light-emitting layer, and a second conductive layer. The first conductive layer is connected to the base layer, and the second conductive layer is connected to the protective layer. The adhesion layer is composed of a coupling agent having a first functional group, and the base layer is formed by polymerizing a polymerizable raw material, wherein the polymerizable raw material includes a reactant having a second functional group, and the first functional group can react with the second functional group to form a chemical bond; the first functional group and the second functional group are alkenyl groups; the coupling agent having the first functional group is at least one of vinyltrimethoxysilane and vinyltriethoxysilane; and the reactant having the second functional group is at least one of acrylic epoxy resin and acrylic resin; The thickness of the adhesive layer is 5 to 10 μm; the thickness of the base layer is 5 to 25 μm; the thickness of the first conductive layer is 10 to 15 μm; the thickness of the electrically responsive light-changing layer is 10 to 80 μm; the thickness of the second conductive layer is 10 to 15 μm; and the thickness of the protective layer is 30 to 50 μm. The preparation method of the color-changing thin film composite structure comprises: Step 1: spraying or applying the adhesive layer on the glass layer; Step 2: spraying or applying the slurry of the base layer to the adhesion layer, and then curing it, so that the first functional group of the adhesion layer copolymerizes with the base layer; Step 3: spraying or applying the slurry of the first conductive layer onto the base layer, and then baking; Step 4: spraying or applying the slurry of the electrically responsive color-changing light-emitting layer on the first conductive layer, and then curing it; Step 5: spraying or applying the slurry of the second conductive layer to the electrically responsive color-changing light-emitting layer, and then baking; Step 6: spraying or applying the slurry of the protective layer to the second conductive layer, and then curing; In steps one to six, a spraying process is adopted to adjust the discharge speed and the movement speed of the spray gun to control the thickness of each layer; the base layer, the electrically responsive color-changing light-emitting layer and the protective layer respectively contain photocurable resins, and the curing in steps two, four and six is UV light curing.

2. The method for preparing a color-changing thin film composite structure according to claim 1, characterized in that The protective layer is at least one of an organic silicon coating, a polyurethane coating, and an acrylic coating; the protective layer contains a low surface energy reactant, a toughening reactant, and a multifunctional reactant.

3. The method for preparing a color-changing thin film composite structure according to claim 1, characterized in that The first conductive layer and the second conductive layer are respectively made of conductive paste, and the conductive paste is at least one of nano silver paste and PEDOT:PSS paste; The electrically responsive color-changing light-emitting layer is at least one of PDLC and EC; The PDLC comprises a mixture of glue and nematic liquid crystal, wherein the glue is at least one of a light-curing resin and a heat-curing resin, the glue is an acrylate glue, and the acrylate glue comprises at least one of polyalkyl acrylate bornyl, methacrylate, acrylate isobornyl, methacrylate-2-hydroxyethyl, isobornyl methacrylate, and hydroxyalkyl methacrylate, and the nematic liquid crystal comprises trans-4-(4-propylcyclohexyl)benzonitrile, pentyl methacrylate, and the like. At least one of 1,2-difluoro-4-[2-[(trans, trans)-4'-propyl[1,1'-bicyclohexyl]-4-yl]ethyl]-benzene and 4-(5-butyl-2-pyrimidinyl)benzonitrile; The EC includes a diluent and a color-changing material, the diluent includes at least one of methyl methacrylate and cyclotrimethylolpropane formal acrylate, and the color-changing material includes at least one of p-phenylenediamine derivatives, benzoquinone, ethoxyanthraquinone, imidazolylbenzoquinone, thermosensitive black derivatives, lithium perchlorate, and tetrabutylammonium hexafluorophosphate.

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