INS film and preparation method thereof

Abstract

The invention discloses an INS film which is composed of a surface protection layer, a printing ink layer, an attaching glue layer and a lower base material layer which are sequentially stacked from top to bottom. The surface protection layer is prepared from the following raw materials in parts by weight: 80-130 parts of polyester polyol resin, 30-55 parts of hydroxy acrylic resin, 3-25 parts of an isocyanate curing agent, 4-18 parts of a closed curing agent, 2-23 parts of a chain extender, 0.5-8 parts of a catalyst, 2-8 parts of nano oxide particles and 0.5-3 parts of an ultraviolet light absorber. According to the INS film, an upper base material layer does not need to be arranged, and the surface protection layer well utilizes the high-temperature condition of a high-temperature plastic uptake procedure in preparation of INS parts, so that the closed curing agent is effectively excited to perform secondary cross-linking curing reaction. The INS film provided by the invention has the advantages of low cost, good surface chemical reagent resistance, high heat stretch rate, high hardness and scratch resistance, and excellent ultraviolet irradiation yellowing resistance, and is especially suitable for the field of in-mold decoration.

Description

Technical Field

[0001] The invention relates to the technical field of in-molding decoration (IMD), and in particular to an INS film and a preparation method thereof. Background Art

[0002] In-Molding Decoration (IMD) technology is also known as injection molding surface decoration technology. IMD is currently an internationally popular surface decoration technology, mainly used in surface decoration and functional panels of household appliances, and is often used in mobile phone window lenses and shells, washing machine control panels, refrigerator control panels, air conditioning control panels, car dashboards, rice cooker control panels and other fields of panels, logos and other appearance parts.

[0003] INS process technology, as one of the IMD technologies, is the abbreviation of Film Insert Molding, also known as insert molding process. It prefabricates a patterned film and covers the surface of the part during the injection molding process, so that the surface of the part presents different colors and textures, and the appearance of the part can be quickly adjusted as needed. The film prepared by INS technology has the advantages of high clarity, diverse patterns, and beautiful product appearance. It is currently widely used in the fields of automotive decorative film, home appliance decorative film, toy decorative film, etc., especially in automotive interior film, which can effectively improve the refinement and added value of the product.

[0004] INS film is a decorative functional film used in INS technology, and its surface presents a specific pattern effect. In the process of surface decoration of parts, there are three main processes: the first step is the high-temperature blister process, in which the INS film is infrared heated to a high temperature (generally 130-170°C) in the blister mold to soften it, and then it is shaped into the 3D shape of the target part by high-pressure blister; the second step is the punching process, in which the INS film after blister forming is placed in the matching punching mold for punching, and the invalid area at the edge of the shaped target part is removed to obtain the target part blister; the third step is the injection molding process, in which the punched target part blister is placed in the matching injection mold cavity, and plastic particles are injected on the back of the blister to obtain the target part with a specific pattern decoration effect on the surface.

[0005] As a surface decorative film, one of the most widely used applications of INS film is on the surface of automobile and home appliance parts and components. This application requires INS film to meet demanding comprehensive performance indicators. Because it needs to meet the complexity of the three-dimensional shape of automobile and home appliance parts and components, INS film is required to have a high thermal elongation rate; at the same time, because the end consumers of automobile and home appliance parts and components often need to use various solvents to clean the products during use, the surface of INS film needs to have high chemical resistance and cannot be corroded and discolored by chemical reagents in normal use scenarios (such as car cleaning agents and sunscreens, etc.) to avoid consumer complaints; because the end consumers of automobile and home appliance parts and components often need to use cleaning and touch during use, the surface of INS film needs to have high hardness and scratch resistance.

[0006] In the prior art, patent CN110816001A discloses an automotive interior INS membrane structure and an INS manufacturing process. This automotive interior INS membrane structure includes a first PMMA acrylic layer, a second ink-printed pattern layer, and a third ABS substrate layer. Its surface film layer is a PMMA acrylic layer, which serves as a protective layer to prevent the ink-printed pattern layer from being damaged. However, PMMA acrylic has the disadvantages of poor chemical resistance and scratch resistance as a surface protective film layer, and there are many application scenarios that cannot be met as the surface layer of automotive parts. In addition, the price of PMMA or PC film materials for preparing the surface film layer is high, and the production cost of the prepared INS membrane products is high, which has also become a major drawback restricting the popularization and promotion of INS membranes.

[0007] Patent CN117327438A discloses a stain-resistant protective layer coating, a stain-resistant INS membrane and a preparation method. The INS membrane consists of a protective layer, an ink layer, an adhesive layer and a substrate layer. The surface is a polyurethane coating as a protective layer. The coating has an anti-fouling effect, but it has the disadvantages of low hardness and poor scratch resistance, and cannot meet the application requirements of automotive parts that need to be frequently touched and rubbed.

[0008] Therefore, exploring a simple and effective manufacturing process and developing a low-cost INS film has become an urgent issue to be solved in the field of decorative films, which has important economic and practical value. Summary of the invention

[0009] The technical problem to be solved by the present invention is to provide a low-cost INS film in view of the shortcomings of the prior art. The INS film has the characteristics of high thermal elongation and high hardness and scratch resistance, as well as excellent resistance to yellowing due to ultraviolet radiation and excellent resistance to chemical reagents. The preparation method of the INS film of the present invention has a simple process, is easy to operate, has a low cost, and is convenient for industrial mass production.

[0010] The technical solution adopted by the present invention to solve the above technical problems is: an INS film, which is composed of a surface protection layer, a printing ink layer, a bonding glue layer and a lower substrate layer stacked in sequence from top to bottom, and the raw materials of the surface protection layer are composed of the following materials by weight: 80-130 parts of polyester polyol resin, 30-55 parts of hydroxy acrylic resin, 3-25 parts of isocyanate curing agent, 4-18 parts of blocked curing agent, 2-23 parts of chain extender, 0.5-8 parts of catalyst, 2-8 parts of nano oxide particles, and 0.5-3 parts of ultraviolet absorber.

[0011] The INS film of the present invention is composed of a surface protection layer, a printing ink layer, a bonding glue layer and a lower substrate layer, and does not need to be provided with an upper substrate layer, so the cost is relatively low. The surface protection layer of the INS film of the present invention is a hardening coating that can be activated at high temperature to undergo a secondary curing reaction. The INS film of the present invention has the characteristics of low cost, high thermal elongation, high hardness and scratch resistance, and also has excellent resistance to yellowing due to ultraviolet radiation and excellent surface resistance to chemical reagents.

[0012] The surface INS film can be obtained by adjusting the proportion of each component in the surface protection layer of the INS film of the present invention. Hydroxyl acrylic resin can improve the leveling property of the surface protection layer glue coating liquid and the adhesion of the upper substrate layer. The surface protection layer adopts a combination of isocyanate curing agent and blocked curing agent, so that the surface protection layer has the characteristics of two curing reactions. First, after the surface protection layer glue coating liquid is coated on the upper surface of the upper substrate layer, the isocyanate curing agent and the hydroxyl group undergo the first cross-linking curing reaction when baking at a temperature of 50 to 90°C and baking and maturation at a temperature of 60 to 80°C. At this time, the blocked curing agent is not activated and does not participate in the cross-linking curing reaction; after the first cross-linking curing reaction, the surface protection layer is partially cross-linked and cured inside, and has a certain surface hardness and high thermal stretching properties, which can meet the physical property requirements of high elongation of INS film for complex 3D modeling designs such as automotive parts. When the INS film undergoes the first high-temperature blistering (130 to 170°C) process of parts processing in the INS process, the blocked curing agent in the surface protection layer is activated at high temperature to release the isocyanate group and the remaining hydroxyl group in the coating for the second cross-linking curing reaction. After the second cross-linking and curing occurs, a more compact interpenetrating polymer network structure is formed inside the surface protection layer, which significantly improves the hardness, scratch resistance and chemical resistance of the surface protection layer. In addition, the nano oxide particles in the surface protection layer can further improve the hardness and scratch resistance of the surface protection layer. At the same time, the nano oxide particles have extremely strong ultraviolet absorption and infrared reflection characteristics, and can work synergistically with ultraviolet absorbers to absorb ultraviolet rays, prevent the degradation and aging of the adhesive layer, and make the surface protection layer have excellent anti-ultraviolet irradiation yellowing characteristics. Therefore, the INS film of the present invention has both high thermal elongation and high hardness scratch resistance, and has excellent anti-ultraviolet irradiation yellowing characteristics and excellent surface chemical resistance characteristics, which can meet the different requirements of various parts of automobile interior and exterior decoration for INS film. The INS film of the present invention cancels the upper substrate layer, and compared with the INS film using PC or PMMA base film as the upper substrate layer, the cost advantage is obvious and has strong market competitiveness.

[0013] When the INS film of the present invention is subjected to the first high-temperature blister process of parts processing in the INS process, the recommended blister temperature is 130-170°C, preferably 150-160°C.

[0014] Preferably, the raw materials of the surface protection layer are composed of the following materials by weight: 88-120 parts of polyester polyol resin, 35-48 parts of hydroxy acrylic resin, 5-20 parts of isocyanate curing agent, 6-15 parts of blocked curing agent, 6-20 parts of chain extender, 1-6 parts of catalyst, 3-6 parts of nano oxide particles, and 1-3 parts of ultraviolet absorber. More preferably, the raw materials of the surface protection layer are composed of the following materials by weight: 93-116 parts of polyester polyol resin, 38-46 parts of hydroxy acrylic resin, 7-18 parts of isocyanate curing agent, 8-13 parts of blocked curing agent, 8-16 parts of chain extender, 2-5 parts of catalyst, 4-5 parts of nano oxide particles, and 1-2 parts of ultraviolet absorber.

[0015] Preferably, the molar ratio of hydroxyl-OH and isocyanate-NCO in the raw material of the surface protective layer is -OH / -NCO=0.90-1.35, preferably 1.05-1.35, and more preferably 1.10-1.25; the hydroxyl-OH is the sum of the hydroxyl groups in the polyester polyol resin and the hydroxy acrylic resin, the isocyanate-NCO is the sum of the isocyanate groups in the isocyanate curing agent and the blocked curing agent, and the molar ratio of the isocyanate groups in the isocyanate curing agent and the isocyanate groups in the blocked curing agent is (55-85):(15-45), preferably (58-80):(20-42), and more preferably (65-75):(25-35). By controlling the molar ratio of hydroxyl-OH and isocyanate-NCO in the surface protective layer components, making the hydroxyl group slightly excessive can increase the compactness of the cross-linking reaction, which is beneficial to improving the hardness, scratch resistance and chemical resistance of the surface protective layer.

[0016] Preferably, the number average molecular weight of the polyester polyol resin is 500-5000, preferably 1000-3000; the hydroxyl value of the polyester polyol resin is 10-250 mgKOH / g, preferably 30-150 mgKOH / g, and more preferably 40-120 mgKOH / g; the hydroxyl value of the hydroxy acrylic resin is 10-140 mgKOH / g, preferably 30-100 mgKOH / g, and more preferably 35-80 mgKOH / g; the glass transition temperature of the hydroxy acrylic resin is -10-70°C, preferably 0-50°C.

[0017] Preferably, the polyester polyol resin is one or a combination of at least two of polycarbonate polyol (PCDL), polycaprolactone polyol (PCL), and adipic acid polyester polyol. The adipic acid polyester polyol can be selected from one or a combination of at least two of polybutylene oxalate diol, polyethylene oxalate diol, and polyhexane oxalate diol. The polyester polyol resin is preferably polycarbonate polyol. Further, the polycarbonate polyol (PCDL) includes but is not limited to: one or a combination of at least two of the PCDL polycarbonate diol series of Asahi Kasei Corporation of Japan and the PCDL polycarbonate diol series of Ube Industries, Ltd. of Japan. Further, the polycaprolactone polyol (PCL) includes but is not limited to: the PCL series of polycaprolactone polyols of Daicel Chemical Industries, Ltd. of Japan, the PCL series of Pasto of France. One or a combination of at least two of the polycaprolactone polyol series.

[0018] Preferably, the isocyanate curing agent is selected from one or a combination of at least two of aliphatic isocyanates, or the isocyanate curing agent is selected from one or a combination of at least two of aliphatic isocyanates with rigid groups; the blocked curing agent is a blocked isocyanate curing agent, and the activation temperature of the blocked isocyanate curing agent is 100-150°C, preferably 110-140°C, and further preferably 120-130°C. After being activated at the activation temperature, the blocked isocyanate curing agent releases isocyanate groups to undergo cross-linking and curing reactions with hydroxyl groups on the molecular chains of the polyester polyol resin and the hydroxyl acrylic resin. Below the activation temperature, the blocked isocyanate curing agent remains inert and lurks in the surface protective layer without participating in the cross-linking and curing reaction; the blocked isocyanate curing agent is selected from one or a combination of at least two of blocked aliphatic isocyanates, blocked aromatic isocyanates, and blocked alicyclic isocyanates.

[0019] Preferably, the aliphatic isocyanate is selected from one or a combination of at least two of the following products: isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), meta-xylylene diisocyanate (XDI), 2,4,4-trimethylhexane diisocyanate (TMHDI), methylcyclohexylene diisocyanate (HTDI), dicyclohexylmethylene diisocyanate (HMDI); or, the aliphatic isocyanate with a rigid group is selected from one or a combination of at least two of the following products: isophorone diisocyanate (IPDI), methylcyclohexylene diisocyanate (HTDI), dicyclohexylmethylene diisocyanate (HMDI). The blocked isocyanate curing agent can be selected from one of the following commercially available products or a combination of at least two of them: HDF-75 (unsealing temperature 140°C), IPDFS-50 (unsealing temperature 140°C), SBN-70D (unsealing temperature 110°C), MF-B60X (unsealing temperature 120°C), TPA-B80X (unsealing temperature 130°C) of Jingxin Huiming Technology Co., Ltd., YL-GB9300 (unsealing temperature 110-130°C) of Yele Chemical, Trixene BI 7982 (unsealing temperature 110-120°C), BI 7960 (unsealing temperature 110-120°C), BI 7951 (unsealing temperature 110-120℃), BI7984 (unsealing temperature 150℃), Guangzhou Haoyi New Material Technology Co., Ltd.'s HF-4401 (unsealing temperature 110-120℃), HF-4268 (unsealing temperature 110-120℃), HF-4238 (unsealing temperature 120℃), HF-4310 (unsealing temperature 120℃), HF-5138 (unsealing temperature 130℃), HF-4357 (unsealing temperature 130℃), HF-5160 (unsealing temperature 130℃).

[0020] Preferably, the chain extender is selected from one or a combination of at least two of ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, diethylene glycol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, and 1,4-cyclohexanedimethanol hydroquinone bis(2-hydroxyethyl) ether; the catalyst is selected from one of organic tin, organic bismuth, organic lead, organic zinc, tetraisobutyl titanate, tetramethylbutylene diamine, and triethylene diamine. or a combination of at least two; the nano-oxide particles are selected from one of nano-silicon dioxide particles, nano-titanium dioxide particles, and nano-zinc dioxide particles, or a combination of at least two of them, preferably nano-silicon dioxide particles; the particle size of the nano-oxide particles is 20 to 500 μm, preferably 50 to 300 μm, and further preferably 100 to 200 μm; the ultraviolet absorber is selected from one of benzotriazole, formamidine, and hindered amine ultraviolet absorbers, or a combination of at least two of them.

[0021] Preferably, the thickness of the surface protection layer is 5 to 35 μm, preferably 8 to 28 μm, and further preferably 12 to 25 μm. The thermal stretching rate of the surface protection layer is 100 to 400%, preferably 180 to 300%. The material of the printing ink layer is acrylic ink, and the thickness of the printing ink layer is 5 to 10 μm. The material of the bonding glue layer is polyurethane-type thermosetting glue, and the thickness of the bonding glue layer is 8 to 20 μm. The material of the lower substrate layer is a terpolymer of acrylonitrile / butadiene / styrene (ABS) or polycarbonate (PC), and the thickness of the lower substrate layer is 300 to 500 μm.

[0022] A method for preparing the above-mentioned INS membrane comprises the following steps:

[0023] a. Accurately weigh the weight of each raw material of the surface protection layer, add it to the organic solvent, and stir it evenly by ultrasonic wave to obtain a glue coating liquid of the surface protection layer, wherein the organic solvent is selected from one or a combination of at least two of isopropyl alcohol, ethyl acetate, butyl acetate, butyl acrylate, butanone, cyclohexanone, propylene glycol methyl ether acetate, and propylene glycol methyl ether;

[0024] b. The release surface of the release substrate is uniformly coated with the glue coating liquid of the surface protection layer, and then the release substrate is placed in an oven and baked at a temperature of 50 to 90° C. After the baking is completed, a surface protection layer is formed on the release surface of the release substrate to obtain a semi-finished product A with a surface protection layer, and the semi-finished product A is then placed at a temperature of 60 to 80° C. and baked for 48 hours;

[0025] In step b, the release substrate may be made of PET material, and the thickness of the release substrate is 30 to 250 μm, preferably 50 to 150 μm, and more preferably 75 to 100 μm;

[0026] c. Performing texture printing on the surface of the surface protective layer of the semi-finished product A after baking and ripening to obtain a semi-finished product B with a printing ink layer;

[0027] d. Apply laminating glue on the upper surface of the lower substrate layer, and then laminate the laminating glue with the printed ink layer on the semi-finished product B to obtain a semi-finished INS film. Then, bake the semi-finished INS film at 60-80°C for 72 hours, and then peel off the release substrate to obtain a finished INS film.

[0028] Compared with the prior art, the present invention has the following advantages:

[0029] (1) The INS film of the present invention is composed of a surface protection layer, a printing ink layer, a bonding glue layer and a lower substrate layer. There is no need to set an upper substrate layer, the cost is low, and it has strong market competitiveness. The surface protection layer of the INS film of the present invention makes good use of the high temperature conditions of the high temperature blister process of the INS film in the preparation of INS parts. The high temperature conditions can effectively stimulate the closed curing agent in the surface protection layer of the INS film, and carry out a secondary cross-linking curing reaction, so that the hardness and scratch resistance of the surface protection layer and the chemical reagent resistance are significantly improved. Compared with conventional INS films, the INS film of the present invention has obvious advantages, low cost, and excellent comprehensive performance. The INS film of the present invention effectively overcomes the shortcomings of conventional INS films that cannot take into account both high thermal stretch rate and high hardness scratch resistance, and solves the problem of poor chemical reagent resistance of the surface of conventional INS films. At the same time, the preparation method of the INS film of the present invention adopts the currently mature optical film coating process, which is simple in process, easy to operate, low in cost, and convenient for industrial mass production.

[0030] (2) The INS film of the present invention is a decorative film that has the characteristics of low cost, high thermal elongation, high hardness and scratch resistance, and also has excellent resistance to yellowing due to ultraviolet radiation and excellent surface resistance to chemical agents. It is particularly suitable for the field of in-mold decoration and can be injection molded into various parts for interior and exterior decoration of automobiles, household appliances, furniture and electronic products. It can also be attached to glass or transparent plastic parts for decorative effect. It is particularly suitable for surface decoration of automobile parts with complex shapes requiring high thermal elongation or automobile or household appliance interior and exterior parts that are frequently touched by end consumers and require high hardness and excellent scratch resistance, but is not limited to the products listed above. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 Schematic diagram of the structure of the INS membrane of Examples 1 to 12 and Comparative Examples 1 to 3. DETAILED DESCRIPTION

[0032] The present invention is further described below in conjunction with the examples and drawings. The following examples are only detailed descriptions of the present invention and are not intended to limit the scope of protection claimed by the present invention. The methods are conventional methods unless otherwise specified. The raw materials are commercially available products unless otherwise specified.

[0033] The INS membranes of Examples 1 to 12 and Comparative Examples 1 to 3 are as follows Figure 1 As shown, they are composed of a surface protection layer 101, a printing ink layer 102, a bonding glue layer 103 and a lower substrate layer 104 stacked in sequence from top to bottom.

[0034] The raw materials of the surface protective layer of the INS film of Example 1 are composed of the following materials by weight: 130 parts of polyester polyol resin, 40 parts of hydroxyl acrylic resin, 17 parts of isocyanate curing agent, 9 parts of blocked curing agent, 20 parts of chain extender, 3 parts of catalyst, 4 parts of nano oxide particles and 2 parts of ultraviolet absorber, wherein the polyester polyol resin is adipic acid polyester polyol, whose number average molecular weight is 2000 and hydroxyl value is 65 mgKOH / g; the hydroxyl value of the hydroxyl acrylic resin is 120 mgKOH / g and the glass transition temperature (Tg value) is -5°C; the isocyanate curing agent is 1,4-methylxylene diisocyanate (TMXDI); the activation temperature of the blocked curing agent is 115°C; the chain extender is 1,6-hexanediol; the catalyst is triethylenediamine; the nano oxide particles are nano zinc dioxide particles, whose particle size is 400 μm; and the ultraviolet absorber is a hindered amine ultraviolet absorber. Among them, the molar ratio of hydroxyl -OH and isocyanate -NCO in the raw materials of the surface protective layer is -OH / -NCO=1.04, hydroxyl -OH is the sum of hydroxyl groups in the polyester polyol resin and the hydroxy acrylic resin, isocyanate -NCO is the sum of isocyanate groups in the isocyanate curing agent and the blocked curing agent, and the molar ratio of the isocyanate group in the isocyanate curing agent and the isocyanate group in the blocked curing agent is 55:45.

[0035] The preparation method of the INS membrane of Example 1 comprises the following steps:

[0036] a. Accurately weigh the weight of each raw material of the surface protection layer, add it to propylene glycol methyl ether, and stir it evenly by ultrasonic to obtain a glue coating liquid for the surface protection layer;

[0037] b. The release surface of the release substrate with a thickness of 250 μm is uniformly coated with the glue coating liquid of the surface protection layer, and then the release substrate is placed in an oven and baked at a temperature of 50 to 90° C. After the baking is completed, a surface protection layer is formed on the release surface of the release substrate to obtain a semi-finished product A with a surface protection layer, and the semi-finished product A is then placed at a temperature of 60 to 80° C. and baked for 48 hours;

[0038] c. Performing texture printing on the surface of the surface protective layer of the semi-finished product A after baking and ripening to obtain a semi-finished product B with a printing ink layer;

[0039] d. Apply laminating glue on the upper surface of the lower substrate layer, and then laminate the laminating glue with the printing ink layer on the semi-finished product B to obtain a semi-finished INS film, and then bake the semi-finished INS film at a temperature of 60-80°C for 72 hours, and then peel off the release substrate to obtain a finished INS film, wherein the thickness of the surface protection layer is 35 μm; the material of the printing ink layer is acrylic ink, and the thickness of the printing ink layer is 5 μm; the material of the laminating glue layer is polyurethane type thermosetting glue, and the thickness of the laminating glue layer is 8 μm; the material of the lower substrate layer is ABS, and the thickness of the lower substrate layer is 450 μm.

[0040] When the INS film of Example 1 is subjected to the first high-temperature blister process of parts processing in the INS process, the recommended blister temperature is 130°C.

[0041] The raw materials of the surface protective layer of the INS film of Example 2 are composed of the following materials by weight: 110 parts of polyester polyol resin, 55 parts of hydroxy acrylic resin, 4 parts of isocyanate curing agent, 6 parts of blocked curing agent, 23 parts of chain extender, 8 parts of catalyst, 3 parts of nano oxide particles and 0.8 parts of ultraviolet absorber, wherein the polyester polyol resin is a polycarbonate polyol having a number average molecular weight of 4000 and a hydroxyl value of 20 mgKOH / g; the hydroxyl value of the hydroxy acrylic resin is 95 mgKOH / g and a glass transition temperature (Tg value) of 38°C; the isocyanate curing agent is 2,4,4-trimethylhexane diisocyanate (TMHDI); the activation temperature of the blocked curing agent is 130°C; the chain extender is 1,6-hexanediol; the catalyst is triethylenediamine; the nano oxide particles are nano silica particles having a particle size of 20 μm; and the ultraviolet absorber is a formamidine ultraviolet absorber. Among them, the molar ratio of hydroxyl -OH and isocyanate -NCO in the raw materials of the surface protective layer is -OH / -NCO=1.00, hydroxyl -OH is the sum of hydroxyl groups in the polyester polyol resin and the hydroxy acrylic resin, isocyanate -NCO is the sum of isocyanate groups in the isocyanate curing agent and the blocked curing agent, and the molar ratio of the isocyanate group in the isocyanate curing agent and the isocyanate group in the blocked curing agent is 82:18.

[0042] The difference between the preparation method of the INS film of Example 1 and the preparation method of the INS film of Example 2 is that butyl acrylate is used as the organic solvent in the glue coating liquid, and the thickness of the release substrate used is 125 μm; the thickness of the surface protection layer is 5 μm; the thickness of the printing ink layer is 8 μm; the thickness of the bonding glue layer is 8 μm; the material of the lower substrate layer is ABS, and the thickness of the lower substrate layer is 500 μm.

[0043] When the INS film of Example 2 is subjected to the first high-temperature blister process of parts processing in the INS process, the recommended blister temperature is 150°C.

[0044] The raw materials of the surface protective layer of the INS film of Example 3 are composed of the following materials by weight: 125 parts of polyester polyol resin, 33 parts of hydroxyl acrylic resin, 9 parts of isocyanate curing agent, 15 parts of blocked curing agent, 17 parts of chain extender, 6 parts of catalyst, 2 parts of nano oxide particles and 2.7 parts of ultraviolet absorber, wherein the polyester polyol resin is polycaprolactone polyol, whose number average molecular weight is 1500 and the hydroxyl value is 100 mgKOH / g; the hydroxyl value of the hydroxyl acrylic resin is 130 mgKOH / g and the glass transition temperature (Tg value) is 60°C; the isocyanate curing agent is meta-xylylene diisocyanate (XDI); the activation temperature of the blocked curing agent is 150°C; the chain extender is 3-methyl-1,5-pentanediol; the catalyst is organic zinc; the nano oxide particles are nano zinc dioxide particles with a particle size of 300 μm; and the ultraviolet absorber is a benzotriazole ultraviolet absorber. Among them, the molar ratio of hydroxyl -OH and isocyanate -NCO in the raw materials of the surface protective layer is -OH / -NCO=1.23, hydroxyl -OH is the sum of hydroxyl groups in the polyester polyol resin and the hydroxy acrylic resin, isocyanate -NCO is the sum of isocyanate groups in the isocyanate curing agent and the blocked curing agent, and the molar ratio of the isocyanate group in the isocyanate curing agent and the isocyanate group in the blocked curing agent is 60:40.

[0045] The difference between the preparation method of the INS film of Example 1 and the preparation method of the INS film of Example 3 is that the preparation method of the INS film of Example 3 uses isopropyl alcohol as the organic solvent in the glue coating liquid, and the thickness of the release substrate used is 150 μm; the thickness of the surface protection layer is 20 μm; the thickness of the printing ink layer is 7 μm; the thickness of the bonding glue layer is 15 μm; the material of the lower substrate layer is PC, and the thickness of the lower substrate layer is 400 μm.

[0046] When the INS film of Example 3 is subjected to the first high-temperature blister process of parts processing in the INS process, the recommended blister temperature is 170°C.

[0047] The raw materials of the surface protective layer of the INS film of Example 4 are composed of the following materials by weight: 115 parts of polyester polyol resin, 48 parts of hydroxy acrylic resin, 20 parts of isocyanate curing agent, 14 parts of blocked curing agent, 20 parts of chain extender, 6 parts of catalyst, 6 parts of nano oxide particles and 1 part of ultraviolet absorber, wherein the polyester polyol resin is polycaprolactone polyol, whose number average molecular weight is 1000 and hydroxyl value is 150 mgKOH / g; the hydroxyl value of hydroxy acrylic resin is 30 mgKOH / g and the glass transition temperature (Tg value) is 50°C; the isocyanate curing agent is methyl cyclohexamethylene diisocyanate (HTDI); the activation temperature of the blocked curing agent is 120°C; the chain extender is 1,4-butanediol; the catalyst is tetramethylbutanediamine; the nano oxide particles are nano titanium dioxide particles with a particle size of 50 μm; and the ultraviolet absorber is a hindered amine ultraviolet absorber. Among them, the molar ratio of hydroxyl -OH and isocyanate -NCO in the raw materials of the surface protective layer is -OH / -NCO=1.05, hydroxyl -OH is the sum of hydroxyl groups in the polyester polyol resin and the hydroxy acrylic resin, isocyanate -NCO is the sum of isocyanate groups in the isocyanate curing agent and the blocked curing agent, and the molar ratio of the isocyanate group in the isocyanate curing agent and the isocyanate group in the blocked curing agent is 62:38.

[0048] The difference between the preparation method of the INS film of Example 1 and the preparation method of the INS film of Example 4 is that ethyl acetate is used as the organic solvent in the glue coating liquid, the thickness of the release substrate used is 150 μm; the thickness of the surface protection layer is 28 μm; the thickness of the printing ink layer is 10 μm; the thickness of the bonding glue layer is 20 μm; the material of the lower substrate layer is ABS, and the thickness of the lower substrate layer is 300 μm.

[0049] When the INS film of Example 4 is subjected to the first high-temperature blister process of parts processing in the INS process, the recommended blister temperature is 150°C.

[0050] The raw materials of the surface protective layer of the INS film of Example 5 are composed of the following materials by weight: 88 parts of polyester polyol resin, 35 parts of hydroxyl acrylic resin, 5 parts of isocyanate curing agent, 5 parts of blocked curing agent, 6 parts of chain extender, 1 part of catalyst, 3 parts of nano oxide particles and 3 parts of ultraviolet absorber, wherein the polyester polyol resin is polycarbonate polyol, whose number average molecular weight is 2000 and the hydroxyl value is 55 mgKOH / g; the hydroxyl value of the hydroxyl acrylic resin is 100 mgKOH / g and the glass transition temperature (Tg value) is 0°C; the isocyanate curing agent is isophorone diisocyanate (IPDI); the activation temperature of the blocked curing agent is 140°C; the chain extender is 1,4-butanediol; the catalyst is tetramethylbutanediamine; the nano oxide particles are nano titanium dioxide particles with a particle size of 300 μm; and the ultraviolet absorber is a benzotriazole ultraviolet absorber. Among them, the molar ratio of hydroxyl -OH and isocyanate -NCO in the raw materials of the surface protective layer is -OH / -NCO=1.10, hydroxyl -OH is the sum of hydroxyl groups in the polyester polyol resin and the hydroxy acrylic resin, isocyanate -NCO is the sum of isocyanate groups in the isocyanate curing agent and the blocked curing agent, and the molar ratio of the isocyanate group in the isocyanate curing agent and the isocyanate group in the blocked curing agent is 58:42.

[0051] The difference between the preparation method of the INS film of Example 1 and the preparation method of the INS film of Example 5 is that the preparation method of the INS film of Example 5 uses propylene glycol methyl ether as the organic solvent in the glue coating liquid, and the thickness of the release substrate used is 75 μm; the thickness of the surface protection layer is 8 μm; the thickness of the printing ink layer is 8 μm; the thickness of the bonding glue layer is 13 μm; the material of the lower substrate layer is ABS, and the thickness of the lower substrate layer is 470 μm.

[0052] When the INS film of Example 5 is subjected to the first high-temperature blister process of parts processing in the INS process, the recommended blister temperature is 150°C.

[0053] The raw materials of the surface protective layer of the INS film of Example 6 are composed of the following materials by weight: 120 parts of polyester polyol resin, 37 parts of hydroxyl acrylic resin, 18 parts of isocyanate curing agent, 10 parts of blocked curing agent, 17 parts of chain extender, 4 parts of catalyst, 5 parts of nano oxide particles and 1 part of ultraviolet absorber, wherein the polyester polyol resin is polycaprolactone polyol, whose number average molecular weight is 3500 and the hydroxyl value is 30 mgKOH / g; the hydroxyl value of the hydroxyl acrylic resin is 90 mgKOH / g and the glass transition temperature (Tg value) is 35°C; the isocyanate curing agent is dicyclohexylmethylene diisocyanate (HMDI); the activation temperature of the blocked curing agent is 130°C; the chain extender is 1,5-pentanediol; the catalyst is tetramethylbutanediamine; the nano oxide particles are nano silica particles with a particle size of 150 μm; and the ultraviolet absorber is a benzotriazole ultraviolet absorber. Among them, the molar ratio of hydroxyl -OH and isocyanate -NCO in the raw materials of the surface protective layer is -OH / -NCO=1.25, hydroxyl -OH is the sum of hydroxyl groups in the polyester polyol resin and the hydroxy acrylic resin, isocyanate -NCO is the sum of isocyanate groups in the isocyanate curing agent and the blocked curing agent, and the molar ratio of the isocyanate group in the isocyanate curing agent and the isocyanate group in the blocked curing agent is 80:20.

[0054] The difference between the preparation method of the INS film of Example 1 and the preparation method of the INS film of Example 6 is that ethyl acetate is used as the organic solvent in the glue coating liquid, the thickness of the release substrate used is 50 μm; the thickness of the surface protection layer is 23 μm; the thickness of the printing ink layer is 6 μm; the thickness of the bonding glue layer is 12 μm; the material of the lower substrate layer is PC, and the thickness of the lower substrate layer is 350 μm.

[0055] When the INS film of Example 6 is subjected to the first high-temperature blister process of parts processing in the INS process, the recommended blister temperature is 160°C.

[0056] The raw materials of the surface protective layer of the INS film of Example 7 are composed of the following materials by weight: 116 parts of polyester polyol resin, 42 parts of hydroxy acrylic resin, 18 parts of isocyanate curing agent, 9 parts of blocked curing agent, 12 parts of chain extender, 5 parts of catalyst, 5 parts of nano oxide particles and 2 parts of ultraviolet absorber, wherein the polyester polyol resin is a polycarbonate polyol having a number average molecular weight of 2000 and a hydroxyl value of 80 mgKOH / g; the hydroxyl value of the hydroxy acrylic resin is 80 mgKOH / g and a glass transition temperature (Tg value) of 40°C; the isocyanate curing agent is methyl cyclohexylene diisocyanate (HTDI); the activation temperature of the blocked curing agent is 130°C; the chain extender is 1,5-pentanediol; the catalyst is tetraisobutyl titanate; the nano oxide particles are nano silica particles having a particle size of 100 μm; and the ultraviolet absorber is a hindered amine ultraviolet absorber. Among them, the molar ratio of hydroxyl -OH and isocyanate -NCO in the raw materials of the surface protective layer is -OH / -NCO=1.15, hydroxyl -OH is the sum of hydroxyl groups in the polyester polyol resin and the hydroxy acrylic resin, isocyanate -NCO is the sum of isocyanate groups in the isocyanate curing agent and the blocked curing agent, and the molar ratio of the isocyanate group in the isocyanate curing agent and the isocyanate group in the blocked curing agent is 75:25.

[0057] The difference between the preparation method of the INS film of Example 1 and the preparation method of the INS film of Example 7 is that the preparation method of the INS film of Example 7 uses butanone as the organic solvent in the glue coating liquid, and the thickness of the release substrate used is 75 μm; the thickness of the surface protection layer is 12 μm; the thickness of the printing ink layer is 9 μm; the thickness of the bonding glue layer is 16 μm; the material of the lower substrate layer is ABS, and the thickness of the lower substrate layer is 400 μm.

[0058] When the INS film of Example 7 is subjected to the first high-temperature blister process of parts processing in the INS process, the recommended blister temperature is 160°C.

[0059] The raw materials of the surface protective layer of the INS film of Example 8 are composed of the following materials by weight: 93 parts of polyester polyol resin, 38 parts of hydroxy acrylic resin, 7 parts of isocyanate curing agent, 8 parts of blocked curing agent, 16 parts of chain extender, 2 parts of catalyst, 4 parts of nano oxide particles and 1.5 parts of ultraviolet absorber, wherein the polyester polyol resin is a polycarbonate polyol having a number average molecular weight of 1500 and a hydroxyl value of 120 mgKOH / g; the hydroxyl value of the hydroxy acrylic resin is 35 mgKOH / g and a glass transition temperature (Tg value) of 5°C; the isocyanate curing agent is methyl cyclohexylene diisocyanate (HTDI); the activation temperature of the blocked curing agent is 120°C; the chain extender is 1,5-pentanediol; the catalyst is tetraisobutyl titanate; the nano oxide particles are nano silica particles having a particle size of 150 μm; and the ultraviolet absorber is a hindered amine ultraviolet absorber. Among them, the molar ratio of hydroxyl -OH and isocyanate -NCO in the raw materials of the surface protective layer is -OH / -NCO=1.10, hydroxyl -OH is the sum of hydroxyl groups in the polyester polyol resin and the hydroxy acrylic resin, isocyanate -NCO is the sum of isocyanate groups in the isocyanate curing agent and the blocked curing agent, and the molar ratio of the isocyanate group in the isocyanate curing agent and the isocyanate group in the blocked curing agent is 65:35.

[0060] The difference between the preparation method of the INS film of Example 1 and the preparation method of the INS film of Example 8 is that the preparation method of the INS film of Example 8 uses cyclohexanone as the organic solvent in the glue coating liquid, and the thickness of the release substrate used is 100 μm; the thickness of the surface protection layer is 25 μm; the thickness of the printing ink layer is 7 μm; the thickness of the bonding glue layer is 14 μm; the material of the lower substrate layer is ABS, and the thickness of the lower substrate layer is 380 μm.

[0061] When the INS film of Example 8 is subjected to the first high-temperature blister process of parts processing in the INS process, the recommended blister temperature is 150°C.

[0062] The raw materials of the surface protective layer of the INS film of Example 9 are composed of the following materials by weight: 100 parts of polyester polyol resin, 46 parts of hydroxyl acrylic resin, 12 parts of isocyanate curing agent, 12 parts of blocked curing agent, 8 parts of chain extender, 4 parts of catalyst, 5 parts of nano oxide particles, and 1 part of ultraviolet absorber, wherein the polyester polyol resin is a polycarbonate polyol having a number average molecular weight of 2500 and a hydroxyl value of 50 mgKOH / g; the hydroxyl value of the hydroxyl acrylic resin is 55 mgKOH / g, and the glass transition temperature (Tg value) is 25°C; the isocyanate curing agent is dicyclohexylmethylene diisocyanate (HMDI); the activation temperature of the blocked curing agent is 125°C; the chain extender is 1,4-butanediol; the catalyst is tetraisobutyl titanate; the nano oxide particles are nano silica particles having a particle size of 200 μm; and the ultraviolet absorber is a hindered amine ultraviolet absorber. Among them, the molar ratio of hydroxyl -OH and isocyanate -NCO in the raw materials of the surface protective layer is -OH / -NCO=1.20, hydroxyl -OH is the sum of hydroxyl groups in the polyester polyol resin and the hydroxy acrylic resin, isocyanate -NCO is the sum of isocyanate groups in the isocyanate curing agent and the blocked curing agent, and the molar ratio of the isocyanate group in the isocyanate curing agent and the isocyanate group in the blocked curing agent is 68:32.

[0063] The difference between the preparation method of the INS film of Example 1 and the preparation method of the INS film of Example 9 is that the preparation method of the INS film of Example 9 uses butanone as the organic solvent in the glue coating liquid, and the thickness of the release substrate used is 75 μm; the thickness of the surface protection layer is 20 μm; the thickness of the printing ink layer is 8 μm; the thickness of the bonding glue layer is 12 μm; the material of the lower substrate layer is ABS, and the thickness of the lower substrate layer is 400 μm.

[0064] When the INS film of Example 9 is subjected to the first high-temperature blister process of parts processing in the INS process, the recommended blister temperature is 155°C.

[0065] The raw materials of the surface protective layer of the INS film of Example 10 are composed of the following materials by weight: 100 parts of polyester polyol resin, 30 parts of hydroxyl acrylic resin, 10 parts of isocyanate curing agent, 10 parts of blocked curing agent, 15 parts of chain extender, 7 parts of catalyst, 6 parts of nano oxide particles and 2 parts of ultraviolet absorber, wherein the polyester polyol resin is adipic acid polyester polyol, whose number average molecular weight is 3000 and hydroxyl value is 40 mgKOH / g; the hydroxyl value of the hydroxyl acrylic resin is 140 mgKOH / g and the glass transition temperature (Tg value) is 70°C; the isocyanate curing agent is dicyclohexylmethylene diisocyanate (HMDI); the activation temperature of the blocked curing agent is 130°C; the chain extender is 3-methyl-1,5-pentanediol; the catalyst is organic zinc; the nano oxide particles are nano zinc dioxide particles with a particle size of 150 μm; and the ultraviolet absorber is a hindered amine ultraviolet absorber. Among them, the molar ratio of hydroxyl -OH and isocyanate -NCO in the raw materials of the surface protective layer is -OH / -NCO=0.90, hydroxyl -OH is the sum of hydroxyl groups in the polyester polyol resin and the hydroxy acrylic resin, isocyanate -NCO is the sum of isocyanate groups in the isocyanate curing agent and the blocked curing agent, and the molar ratio of the isocyanate group in the isocyanate curing agent and the isocyanate group in the blocked curing agent is 58:42.

[0066] The difference between the preparation method of the INS film of Example 1 and the preparation method of the INS film of Example 1 is that the preparation method of the INS film of Example 10 uses ethyl acetate as the organic solvent in the glue coating liquid, and the thickness of the release substrate used is 75 μm; the thickness of the surface protection layer is 6 μm; the thickness of the printing ink layer is 6 μm; the thickness of the bonding glue layer is 10 μm; the material of the lower substrate layer is ABS, and the thickness of the lower substrate layer is 480 μm.

[0067] When the INS film of Example 10 is subjected to the first high-temperature blister process of parts processing in the INS process, the recommended blister temperature is 150°C.

[0068] The raw materials of the surface protective layer of the INS film of Example 11 are composed of the following materials by weight: 80 parts of polyester polyol resin, 55 parts of hydroxy acrylic resin, 3 parts of isocyanate curing agent, 2 parts of blocked curing agent, 2 parts of chain extender, 0.5 parts of catalyst, 2 parts of nano oxide particles and 0.5 parts of ultraviolet absorber, wherein the polyester polyol resin is adipic acid-based polyester polyol, whose number average molecular weight is 5000 and the hydroxyl value is 10 mgKOH / g; the hydroxyl value of the hydroxy acrylic resin is 10 mgKOH / g and the glass transition temperature (Tg value) is -10°C; the isocyanate curing agent is isophorone diisocyanate (IPDI); the activation temperature of the blocked curing agent is 150°C; the chain extender is 1,2-propylene glycol; the catalyst is organic tin; the nano oxide particles are nano silica particles with a particle size of 200 μm; and the ultraviolet absorber is a benzotriazole ultraviolet absorber. Among them, the molar ratio of hydroxyl -OH and isocyanate -NCO in the raw materials of the surface protective layer is -OH / -NCO=0.90, hydroxyl -OH is the sum of hydroxyl groups in the polyester polyol resin and the hydroxy acrylic resin, isocyanate -NCO is the sum of isocyanate groups in the isocyanate curing agent and the blocked curing agent, and the molar ratio of the isocyanate group in the isocyanate curing agent and the isocyanate group in the blocked curing agent is 60:40.

[0069] The difference between the preparation method of the INS film of Example 1 and the preparation method of the INS film of Example 1 is that the preparation method of the INS film of Example 11 uses butyl acetate as the organic solvent in the glue coating liquid, and the thickness of the release substrate used is 25 μm; the thickness of the surface protection layer is 8 μm; the thickness of the printing ink layer is 5 μm; the thickness of the bonding glue layer is 17 μm; the material of the lower substrate layer is PC, and the thickness of the lower substrate layer is 500 μm.

[0070] When the INS film of Example 11 is subjected to the first high-temperature blister process of parts processing in the INS process, the recommended blister temperature is 160°C.

[0071] The raw materials of the surface protective layer of the INS film of Example 12 are composed of the following materials by weight: 90 parts of polyester polyol resin, 40 parts of hydroxy acrylic resin, 22 parts of isocyanate curing agent, 4 parts of blocked curing agent, 10 parts of chain extender, 3 parts of catalyst, 8 parts of nano oxide particles and 3 parts of ultraviolet absorber, wherein the polyester polyol resin is polycaprolactone polyol, whose number average molecular weight is 500 and the hydroxyl value is 250 mgKOH / g; the hydroxyl value of the hydroxy acrylic resin is 20 mgKOH / g and the glass transition temperature (Tg value) is 5°C; the isocyanate curing agent is hexamethylene diisocyanate (HDI); the activation temperature of the blocked curing agent is 110°C; the chain extender is neopentyl glycol; the catalyst is organic zinc; the nano oxide particles are nano titanium dioxide particles with a particle size of 500 μm; and the ultraviolet absorber is a formamidine ultraviolet absorber. Among them, the molar ratio of hydroxyl -OH and isocyanate -NCO in the raw materials of the surface protective layer is -OH / -NCO=1.30, hydroxyl -OH is the sum of hydroxyl groups in the polyester polyol resin and the hydroxy acrylic resin, isocyanate -NCO is the sum of isocyanate groups in the isocyanate curing agent and the blocked curing agent, and the molar ratio of the isocyanate group in the isocyanate curing agent and the isocyanate group in the blocked curing agent is 85:15.

[0072] The difference between the preparation method of the INS film of Example 1 and the preparation method of the INS film of Example 1 is that the preparation method of the INS film of Example 12 uses ethyl acetate as the organic solvent in the glue coating liquid, and the thickness of the release substrate used is 125 μm; the thickness of the surface protection layer is 12 μm; the thickness of the printing ink layer is 10 μm; the thickness of the bonding glue layer is 11 μm; the material of the lower substrate layer is PC, and the thickness of the lower substrate layer is 450 μm.

[0073] When the INS film of Example 12 is subjected to the first high-temperature blister process of parts processing in the INS process, the recommended blister temperature is 145°C.

[0074] The INS film of Comparative Example 1 has a surface protective layer in which the amount of blocked curing agent is zero, and the raw materials of the surface protective layer are composed of the following materials by weight: 80 parts of polyester polyol resin, 35 parts of hydroxy acrylic resin, 5 parts of isocyanate curing agent, 6 parts of chain extender, 1 part of catalyst, 3 parts of nano oxide particles and 3 parts of ultraviolet absorber, wherein the polyester polyol resin is a polycarbonate polyol having a number average molecular weight of 2000 and a hydroxyl value of 55 mgKOH / g; the hydroxyl value of the hydroxy acrylic resin is 100 mgKOH / g, and the glass transition temperature (Tg value) is 0°C; the isocyanate curing agent is isophorone diisocyanate (IPDI); the chain extender is 1,4-butanediol; the catalyst is tetramethylbutanediamine; the nano oxide particles are nano titanium dioxide particles having a particle size of 300 μm; and the ultraviolet absorber is a benzotriazole ultraviolet absorber. Among them, the molar ratio of hydroxyl group -OH and isocyanate group -NCO in the raw material of the surface protection layer is -OH / -NCO=0.65, hydroxyl group -OH is the sum of hydroxyl groups in the polyester polyol resin and the hydroxy acrylic resin, and isocyanate group -NCO is the sum of isocyanate groups in the isocyanate curing agent.

[0075] The difference between the preparation method of the INS film of Example 1 and the preparation method of the INS film of Comparative Example 1 is that the preparation method of the INS film of Comparative Example 1 uses propylene glycol methyl ether as the organic solvent in the glue coating liquid, and the thickness of the release substrate used is 75 μm; the thickness of the surface protection layer is 8 μm; the thickness of the printing ink layer is 5 μm; the thickness of the bonding glue layer is 8 μm; the material of the lower substrate layer is ABS, and the thickness of the lower substrate layer is 450 μm.

[0076] When the INS film of comparative example 1 is subjected to the first high-temperature blister process of parts processing of the INS process, the recommended blister temperature is 150°C.

[0077] In the INS film of Comparative Example 2, the amount of blocked curing agent, ultraviolet absorber and nano oxide particles in the surface protective layer is too low. The raw materials of the surface protective layer are composed of the following materials by weight: 93 parts of polyester polyol resin, 38 parts of hydroxy acrylic resin, 40 parts of isocyanate curing agent, 1 part of blocked curing agent, 16 parts of chain extender, 2 parts of catalyst, 0.2 parts of nano oxide particles and 0.1 parts of ultraviolet absorber, wherein the polyester polyol resin is polycarbonate polyol, and its number average molecular weight is 1.3777 W / m2. The amount is 1500, the hydroxyl value is 120mgKOH / g; the hydroxyl value of the hydroxy acrylic resin is 35mgKOH / g, and the glass transition temperature (Tg value) is 5°C; the isocyanate curing agent is methylcyclohexylene diisocyanate (HTDI); the activation temperature of the blocked curing agent is 120°C; the chain extender is 1,5-pentanediol; the catalyst is tetraisobutyl titanate; the nano oxide particles are nano silica particles with a particle size of 150μm; the ultraviolet absorber is a hindered amine ultraviolet absorber. Among them, the molar ratio of hydroxyl -OH and isocyanate -NCO in the raw material of the surface protective layer is -OH / -NCO=1.15, hydroxyl -OH is the sum of hydroxyl groups in the polyester polyol resin and the hydroxy acrylic resin, isocyanate -NCO is the sum of isocyanate groups in the isocyanate curing agent and the blocked curing agent, and the molar ratio of isocyanate groups in the isocyanate curing agent and the blocked curing agent is 97:3.

[0078] The difference between the preparation method of the INS film of Example 1 and the preparation method of the INS film of Comparative Example 2 is that cyclohexanone is used as the organic solvent in the glue coating liquid, and the thickness of the release substrate used is 100 μm; the thickness of the surface protection layer is 25 μm; the thickness of the printing ink layer is 7 μm; the thickness of the bonding glue layer is 14 μm; the material of the lower substrate layer is ABS, and the thickness of the lower substrate layer is 380 μm.

[0079] When the INS film of comparative example 2 is subjected to the first high-temperature blister process of parts processing of the INS process, the recommended blister temperature is 150°C.

[0080] In the INS film of Comparative Example 3, the amount of hydroxy acrylic resin in its surface protective layer is too low, and the raw materials of its surface protective layer are composed of the following materials by weight: 100 parts of polyester polyol resin, 15 parts of hydroxy acrylic resin, 12 parts of isocyanate curing agent, 12 parts of blocked curing agent, 8 parts of chain extender, 4 parts of catalyst, 5 parts of nano oxide particles, and 1 part of ultraviolet absorber, wherein the polyester polyol resin is a polycarbonate polyol having a number average molecular weight of 2500 and a hydroxyl value of 50 mgKOH / g; the hydroxyl value of the hydroxy acrylic resin is 55 mgKOH / g, and the glass transition temperature (Tg value) is 25°C; the isocyanate curing agent is dicyclohexylmethylene diisocyanate (HMDI); the activation temperature of the blocked curing agent is 125°C; the chain extender is 1,5-pentanediol; the catalyst is tetraisobutyl titanate; the nano oxide particles are nano silica particles having a particle size of 200 μm; and the ultraviolet absorber is a hindered amine ultraviolet absorber. Among them, the molar ratio of hydroxyl -OH and isocyanate -NCO in the raw materials of the surface protective layer is -OH / -NCO=1.15, hydroxyl -OH is the sum of hydroxyl groups in the polyester polyol resin and the hydroxy acrylic resin, isocyanate -NCO is the sum of isocyanate groups in the isocyanate curing agent and the blocked curing agent, and the molar ratio of the isocyanate group in the isocyanate curing agent and the isocyanate group in the blocked curing agent is 67:33.

[0081] The difference between the preparation method of the INS film of Example 1 and the preparation method of the INS film of Comparative Example 3 is that butyl acetate is used as the organic solvent in the glue coating liquid, and the thickness of the release substrate used is 75 μm; the thickness of the surface protection layer is 20 μm; the thickness of the printing ink layer is 8 μm; the thickness of the bonding glue layer is 12 μm; the material of the lower substrate layer is ABS, and the thickness of the lower substrate layer is 400 μm.

[0082] When the INS film of comparative example 3 is subjected to the first high-temperature blister process of parts processing of the INS process, the recommended blister temperature is 155°C.

[0083] The following is an evaluation of the performance of the INS membranes of Examples 1 to 12 and Comparative Examples 1 to 3, and the materials and equipment required are all existing materials and equipment. The evaluation of the performance of the INS membranes includes:

[0084] 1. INS film adhesion test: Experimental test is carried out according to GB / T9286-1998 (100 grid method).

[0085] 2. Surface hardness test of INS film: Pencil hardness is tested according to GB / T 6739-1996.

[0086] 3. Surface hardness test of INS film injection molded parts: Pencil hardness is tested in accordance with GB / T 6739-1996, where the hardness grades from soft to hard are 6B, 5B, 4B, 3B, 2B, B, HB, F, H, 2H, 3H, 4H, 5H, 6H, a total of 14 hardness grades.

[0087] 4. INS film thermal stretchability test: According to GB / T 1040.1-2006, the INS film was tested at a temperature of 120°C.

[0088] 5. Scratch resistance test: TEBER 710 five-finger scratch tester, weight 7N, the scratch finger assembly and the INS film injection molded test sample are placed vertically, slide back and forth 10 times, and observe whether there is any change on the surface of the diaphragm.

[0089] 6. Anti-ultraviolet yellowing test: Use a xenon lamp accelerated aging box to irradiate the INS film injection molded parts under the test conditions specified in IOS105-B06 condition 5 with a total irradiation of 1240.8KJ / m 2 The ΔE*ab value of the appearance change is evaluated after the cumulative irradiation. The smaller the ΔE*ab value, the less obvious the yellowing after ultraviolet irradiation; the larger the ΔE*ab value, the more obvious the yellowing after ultraviolet irradiation.

[0090] 7. Chemical resistance test: Use the high temperature drip method to test the effects of gasoline (92#), window cleaning agent (Turtle Hard Shell Glass Water), butanone, pesticides and artificial sweat on the surface appearance of the INS film injection molded parts; High temperature drip method test steps: Take 0.1mL of liquid and drop it on the surface of the test piece and spread it naturally. After exposure for 10 minutes, put it in a 60°C oven and bake it for 30 minutes. Then take out the part and leave it for 24 hours, and then evaluate the appearance of the test area surface.

[0091] 8. Sunscreen corrosion resistance test: Unfold 50*50mm medical gauze and fix it on the surface of INS membrane injection molded parts, and evenly apply an excessive amount of hand cream (brand: La Roche Posay Anthelios, SPF 50+) on the gauze. Spread the gauze soaked with sunscreen on the surface of INS membrane injection molded parts, and then put the tested INS membrane injection molded parts in an 80℃ oven for 24 hours. After wiping off the sunscreen on the surface of the INS membrane injection molded parts, place them at room temperature for 4 hours, and then evaluate the appearance and adhesion of the sunscreen test position (perform experimental tests in accordance with GB / T9286-1998 (100-grid method)).

[0092] The main performance test results of the INS membranes of Examples 1 to 12 and Comparative Examples 1 to 3 are shown in Tables 1 and 2.

[0093] Table 1: Main performance test results of INS membranes of Examples 1 to 12 and Comparative Examples 1 to 3

[0094]

[0095]

[0096] Table 2: Main performance test results of INS membranes of Examples 1 to 12 and Comparative Examples 1 to 3

[0097]

[0098] From the test results of Examples 1 to 12 and Comparative Examples 1 to 3 shown in Table 1 and Table 2, it can be concluded that the INS film of the present invention has both high thermal elongation and high hardness scratch resistance, and also has excellent resistance to yellowing due to ultraviolet radiation and excellent surface resistance to chemical agents.

[0099] The INS film of the present invention is composed of a surface protection layer, a printing ink layer, a bonding glue layer and a lower substrate layer, and does not need to be provided with an upper substrate layer, has low cost and strong market competitiveness. At the same time, the preparation method of the INS film of the present invention adopts the currently mature optical film coating process, has a simple process, is easy to operate, has low cost, and is convenient for industrial mass production.

[0100] By regulating the proportion of each component in the surface protection layer of the INS membrane of the present invention, an INS membrane with excellent surface comprehensive performance can be obtained. By controlling the molar ratio of hydroxyl-OH and isocyanate-NCO in the surface protection layer components, a slight excess of hydroxyl can increase the compactness of the cross-linking reaction, which is beneficial to improving the hardness, scratch resistance and chemical resistance of the surface protection layer. Hydroxyl acrylic resin can improve the leveling of the surface protection layer glue coating liquid and the adhesion of the upper substrate layer. The surface protection layer adopts a combination of isocyanate curing agent and blocked curing agent, so that the surface protection layer has the characteristics of two curing reactions, wherein after the first cross-linking curing reaction, the surface protection layer is partially cross-linked and cured, and has a certain surface hardness and higher thermal stretching characteristics; after the second cross-linking curing occurs, a more dense interpenetrating polymer network structure is formed inside the surface protection layer, so that the hardness, scratch resistance and chemical resistance of the surface protection layer are significantly improved. In addition, the nano-oxide particles in the surface protective layer can improve the hardness and scratch resistance of the surface protective layer. At the same time, the nano-oxide particles have extremely strong ultraviolet absorption and infrared reflection properties, and can synergize with ultraviolet absorbers to absorb ultraviolet rays, prevent the adhesive layer from degradation and aging, and make the surface protective layer have excellent anti-yellowing properties due to ultraviolet radiation.

[0101] Among them, the INS films prepared in Examples 4 to 9 of the present invention have the characteristics of high thermal elongation, high hardness and scratch resistance. At the same time, the cost is low, and it has excellent anti-ultraviolet yellowing properties and excellent surface resistance to chemical agents, and the comprehensive performance is better. The adhesion of the prepared INS film is level 0, the surface hardness of the INS film after the first cross-linking and curing reaction is between B-HB, and the thermal elongation is 200-285%; the surface hardness of the INS film injection molded part prepared after the second cross-linking and curing occurs is 2H, the anti-yellowing resistance ΔE*ab value is less than 1, and the chemical resistance and sunscreen resistance test performance are excellent. In particular, the adhesion of the INS film prepared in Examples 7, 8 and 9 is level 0, the surface hardness of the INS film after the first cross-linking and curing reaction is HB, and the thermal elongation is 245-275%; the surface hardness of the INS film injection molded part prepared after the second cross-linking and curing occurs is 2H, the anti-yellowing resistance ΔE*ab value is less than 0.5, and the chemical resistance and sunscreen resistance test performance are excellent.

[0102] The above embodiments and drawings do not limit the product form and style of the present invention. Any appropriate changes or modifications made thereto by ordinary technicians in the relevant technical field should be deemed to be within the patent scope of the present invention.

Claims

1. An INS membrane, characterized in that: The INS film consists of a surface protection layer, a printing ink layer, a bonding glue layer and a lower substrate layer stacked in sequence from top to bottom. The raw materials of the surface protection layer consist of the following materials by weight: 80-130 parts of polyester polyol resin, 30-55 parts of hydroxy acrylic resin, 3-25 parts of isocyanate curing agent, 4-18 parts of blocked curing agent, 2-23 parts of chain extender, 0.5-8 parts of catalyst, 2-8 parts of nano oxide particles and 0.5-3 parts of ultraviolet absorber.

2. The INS membrane according to claim 1, characterized in that The raw materials of the surface protection layer are composed of the following materials by weight: 88-120 parts of polyester polyol resin, 35-48 parts of hydroxy acrylic resin, 5-20 parts of isocyanate curing agent, 6-15 parts of blocked curing agent, 6-20 parts of chain extender, 1-6 parts of catalyst, 3-6 parts of nano oxide particles, and 1-3 parts of ultraviolet absorber.

3. The INS membrane according to claim 1, characterized in that The molar ratio of hydroxyl -OH and isocyanate -NCO in the raw materials of the surface protective layer is -OH / -NCO=0.90~1.35, the hydroxyl -OH is the sum of hydroxyl groups in the polyester polyol resin and the hydroxy acrylic resin, the isocyanate -NCO is the sum of isocyanate groups in the isocyanate curing agent and the blocked curing agent, and the molar ratio of isocyanate groups in the isocyanate curing agent and the isocyanate groups in the blocked curing agent is (55~85):(15~45).

4. The INS membrane according to claim 1, characterized in that The number average molecular weight of the polyester polyol resin is 500-5000, the hydroxyl value of the polyester polyol resin is 10-250 mgKOH / g, the hydroxyl value of the hydroxy acrylic resin is 10-140 mgKOH / g, and the glass transition temperature of the hydroxy acrylic resin is -10-70°C.

5. The INS membrane according to claim 1, characterized in that The polyester polyol resin is one of polycarbonate polyol, polycaprolactone polyol and adipic acid polyester polyol or a combination of at least two of them.

6. The INS membrane according to claim 1, characterized in that The isocyanate curing agent is selected from one or a combination of at least two of aliphatic isocyanates, or the isocyanate curing agent is selected from one or a combination of at least two of aliphatic isocyanates with rigid groups; the blocked curing agent is a blocked isocyanate curing agent, the activation temperature of the blocked isocyanate curing agent is 100-150°C, the blocked isocyanate curing agent releases isocyanate groups after being activated at the activation temperature to undergo cross-linking and curing reactions with hydroxyl groups on the molecular chains of the polyester polyol resin and the hydroxyl acrylic resin, and the blocked isocyanate curing agent remains inert below the activation temperature and lurks in the surface protective layer without participating in the cross-linking and curing reaction; the blocked isocyanate curing agent is selected from one or a combination of at least two of blocked aliphatic isocyanates, blocked aromatic isocyanates, and blocked alicyclic isocyanates.

7. The INS membrane according to claim 6, characterized in that The aliphatic isocyanate is selected from one or a combination of at least two of the following products: isophorone diisocyanate, hexamethylene diisocyanate, m-xylylene diisocyanate, 2,4,4-trimethylhexane diisocyanate, methylcyclohexylene diisocyanate, dicyclohexylmethylene diisocyanate; or, the aliphatic isocyanate with a rigid group is selected from one or a combination of at least two of the following products: isophorone diisocyanate, methylcyclohexylene diisocyanate, dicyclohexylmethylene diisocyanate.

8. The INS membrane according to claim 1, characterized in that The chain extender is selected from one or a combination of at least two of ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butylene glycol, 1,5-pentanediol, neopentyl glycol, diethylene glycol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, and 1,4-cyclohexanedimethanol hydroquinone bis(2-hydroxyethyl) ether; the catalyst is selected from one or a combination of at least two of organic tin, organic bismuth, organic lead, organic zinc, tetraisobutyl titanate, tetramethylbutylene diamine, and triethylene diamine; the nano-oxide particles are selected from one or a combination of at least two of nano-silicon dioxide particles, nano-titanium dioxide particles, and nano-zinc dioxide particles, and the particle size of the nano-oxide particles is 20 to 500 μm; the ultraviolet absorber is selected from one or a combination of at least two of benzotriazole, formamidine, and hindered amine ultraviolet absorbers.

9. The INS membrane according to claim 1, characterized in that The thickness of the surface protection layer is 5 to 35 μm, and the thermal stretching rate of the surface protection layer is 100 to 400%; the material of the printing ink layer is acrylic ink, and the thickness of the printing ink layer is 5 to 10 μm; the material of the bonding glue layer is polyurethane-type thermosetting glue, and the thickness of the bonding glue layer is 8 to 20 μm; the material of the lower substrate layer is a terpolymer of acrylonitrile / butadiene / styrene or polycarbonate, and the thickness of the lower substrate layer is 300 to 500 μm.

10. A method for preparing an INS membrane according to any one of claims 1 to 9, characterized in that: The following steps are involved: a. Accurately weigh the weight of each raw material of the surface protection layer, add it to the organic solvent, and stir it evenly by ultrasonic wave to obtain a glue coating liquid of the surface protection layer, wherein the organic solvent is selected from one or a combination of at least two of isopropyl alcohol, ethyl acetate, butyl acetate, butyl acrylate, butanone, cyclohexanone, propylene glycol methyl ether acetate, and propylene glycol methyl ether; b. The release surface of the release substrate is uniformly coated with the glue coating liquid of the surface protection layer, and then the release substrate is placed in an oven and baked at a temperature of 50 to 90° C. After the baking is completed, a surface protection layer is formed on the release surface of the release substrate to obtain a semi-finished product A with a surface protection layer, and the semi-finished product A is then placed at a temperature of 60 to 80° C. and baked for 48 hours; c. Performing texture printing on the surface of the surface protective layer of the semi-finished product A after baking and ripening to obtain a semi-finished product B with a printing ink layer; d. Apply laminating glue on the upper surface of the lower substrate layer, and then laminate the laminating glue with the printed ink layer on the semi-finished product B to obtain a semi-finished INS film. Then, bake the semi-finished INS film at 60-80°C for 72 hours, and then peel off the release substrate to obtain a finished INS film.

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