Self-repairing coating, electronic screen protective film and preparation method

Abstract

The embodiment of the present application provides a self-repairing coating, an electronic screen protective film and a preparation method, which relates to the field of protective films. The components of the self-repairing coating include, by weight: 60-70 parts of linear aliphatic polycarbonate polyol, 20-30 parts of hydroxy polyester, 90-110 parts of dual-curing resin, 40-50 parts of acrylate, 60-70 parts of ketone-aldehyde resin, 35-45 parts of aliphatic isocyanate, 1-1.5 parts of free radical photoinitiator, 0.05-0.15 parts of non-organic tin catalyst, 1-5 parts of lubricant, and 170-210 parts of solvent. The electronic screen protective film includes: a base film layer, a first pressure-sensitive adhesive layer, a self-repairing layer, a thermoplastic polyurethane elastomer layer, a second pressure-sensitive adhesive layer and a release film layer, which are stacked in sequence from top to bottom. The protective film has good offset printing, excellent self-repairing ability, and can ensure the self-repairing effect for a long time, and can be used under extreme conditions.

Description

Technical Field

[0001] The present application relates to the field of protective films, and more specifically, to a self-repairing coating, an electronic screen protective film, and a preparation method thereof. Background Art

[0002] With the increasing popularity and innovation of electronic products, electronic screen protective films are also constantly updated, among which mobile phones and mobile phone protective films are the most typical representatives. Consumers initially used mobile phone protective films mainly to protect their mobile phones. Nowadays, the demand for mobile phone protective films is no longer limited to protective functions, and new demands have been put forward: anti-blue light protective films, frosted protective films, anti-peeping protective films, self-repairing protective films and other new films have been born. Among them, self-repairing protective films are mainly used in curved mobile phones.

[0003] At present, the film layer that realizes the self-repairing function in the self-repairing protective film is mostly a thermosetting repair material system, but the offset printing, self-repairing ability and long-term stability of the protective film are poor. Summary of the invention

[0004] In order to solve at least one of the above-mentioned technical problems, the purpose of the embodiments of the present application is to provide a self-repairing coating, an electronic screen protective film and a preparation method. The protective film has good offset printing, excellent self-repairing ability, and can ensure the self-repairing effect for a long time and can be used under extreme conditions.

[0005] In a first aspect, an embodiment of the present application provides a self-repairing coating, the components of which include, by weight:

[0006]

[0007]

[0008] In the above technical solution, the self-healing coating is a dual-curing coating, which is cured by heat and UV light to obtain a self-healing layer. Among them, the linear aliphatic polycarbonate polyol contains a self-healing C=C double bond, which will produce an intermolecular force (polar group) with the second component hydroxyl polyester, affecting the self-healing performance of the film and facilitating self-healing; the self-healing coating contains a wealth of active hydrogen-containing groups (hydrogen bonds, amino groups, hydroxyl groups, etc.), so that the self-healing layer can recover in a short time after being damaged by external forces.

[0009] In a possible implementation, the linear aliphatic polycarbonate polyol is a polymer containing repeated carbonate groups in the main chain of the molecule and hydroxyl groups at the chain end, and can be selected from Covestro Desmophen C1100, Covestro Desmophen C 1200, Desmophen C2200, Desmophen C2100 of Covestro Polymers Co., Ltd., and Asahi Kasei's "Duracell" TM "At least one of the following.

[0010] In a possible implementation, the hydroxy polyester is obtained by a dehydration esterification reaction between a dibasic acid and an excess of a polyol, and can be selected from at least one of Desmophen 670BA, Desmophen 651MPA / X of Covestro Polymer Co., Ltd., and H101, H103, and H104 of the HyPer H10 series of Suzhou Haibote Resin Technology Co., Ltd.

[0011] In one possible implementation, the dual-cure resin is a modified polyurethane acrylate, which can be selected from at least one of 1831A and 1443 of Guangdong Dinglisen New Materials Co., Ltd., D-039 of Changzhou Sante Chemical Co., Ltd., HUV-201A of Suzhou Hangzhi New Materials Co., Ltd., and dual-stage curing coating DHC-92L of Guangzhou Tetrahedron New Materials Technology Co., Ltd.

[0012] In a possible implementation, the acrylate is at least one of A-NOD-N, A-HD-N, 1,4-cyclohexanedimethanol diacrylate, polyethylene glycol diacrylate, ethoxylated trimethylolpropane triacrylate, and caprolactone acrylate produced by Shin-Nakamura Chemical Industry Co., Ltd.;

[0013] and / or, the ketone-aldehyde resin is KR-1021 of Anfeng Industrial Technology Co., Ltd.;

[0014] and / or, the aliphatic isocyanate is at least one of isophorone diisocyanate, hexamethylene diisocyanate, 4'-diisocyanate, methylcyclohexane diisocyanate, trimethylhexamethylene diisocyanate and xylylene diisocyanate;

[0015] and / or, the free radical photoinitiator is a benzophenone derivative;

[0016] and / or, the non-organotin catalyst is at least one of Valikat Bi2810, TMG 160, TMG 720, TMG 634, TMG 612 and TMG 330 of Shanghai Manhai Gaoschmidt Chemical Co., Ltd.;

[0017] And / or, the lubricant is silicone acrylate, which can be TEGO Rad 2250 produced by Evonik;

[0018] And / or, the solvent is at least one of methyl isobutyl ketone, ethyl acetate, methyl acetate, propyl acetate, methyl isobutyl ketone, toluene, xylene, cyclohexane, 120# solvent, cyclohexanone and isopropanol.

[0019] In the second aspect, an embodiment of the present application provides an electronic screen protective film, which includes: a base film layer, a first pressure-sensitive adhesive layer, a self-healing layer, a thermoplastic polyurethane elastomer layer (TPU layer), a second pressure-sensitive adhesive layer and a release film layer stacked in sequence from top to bottom, wherein the self-healing layer is obtained by coating, thermally curing and ultraviolet light curing the self-healing coating provided in the first aspect.

[0020] In the above technical solution, thermoplastic polyurethane elastomer (TPU) has good elasticity and high tensile fracture rate. It is a polymer material with very good recovery properties after the external force is withdrawn. When the protective film formed by the self-repairing layer with the TPU layer as the substrate is subjected to external force and ruptures, the TPU molecules will recover. This effect can be promoted at high temperature, thereby achieving the effect of automatic repair.

[0021] In a possible implementation, the components of the glue corresponding to the first pressure-sensitive adhesive layer include, by weight:

[0022]

[0023]

[0024] In the above technical solution, the first pressure-sensitive adhesive layer is a PU adhesive system, which is used to protect the self-repairing layer and has a small peeling force.

[0025] In a possible implementation, the components of the glue corresponding to the second pressure-sensitive adhesive layer include, by weight:

[0026]

[0027] In the above technical solution, the glue corresponding to the second pressure-sensitive adhesive layer is silicone pressure-sensitive adhesive, which has high peeling force and high hardness.

[0028] In a third aspect, an embodiment of the present application provides a method for preparing the electronic screen protective film provided in the second aspect, which comprises the following steps:

[0029] Disposing a first pressure-sensitive adhesive layer on the base film layer;

[0030] A self-repairing layer, a second pressure-sensitive adhesive layer and a release film layer are respectively arranged on both sides of the thermoplastic polyurethane elastomer layer, so that the first pressure-sensitive adhesive layer and the self-repairing layer are laminated and compounded together.

[0031] In a possible implementation, the following steps are included:

[0032] Applying glue corresponding to the first pressure-sensitive adhesive layer on the base film layer, thermally curing to obtain the first pressure-sensitive adhesive layer, and laminating the first pressure-sensitive adhesive layer with a first release film;

[0033] coating a coating corresponding to the thermoplastic polyurethane elastomer layer on the second release film, thermally curing the coating to obtain the thermoplastic polyurethane elastomer layer, and laminating the thermoplastic polyurethane elastomer layer with a third release film;

[0034] The second release film on the thermoplastic polyurethane elastomer layer is removed, and then a layer of self-repairing coating is coated on the thermoplastic polyurethane elastomer layer, and a self-repairing layer is obtained by heat curing and ultraviolet curing;

[0035] tearing off the first release film on the first pressure-sensitive adhesive layer, laminating the self-repairing layer with the first pressure-sensitive adhesive layer, and curing;

[0036] The third release film on the thermoplastic polyurethane elastomer layer is removed, and a layer of glue corresponding to the second pressure-sensitive layer is coated on the thermoplastic polyurethane elastomer layer, and thermally cured to obtain a second pressure-sensitive adhesive layer, and the second pressure-sensitive adhesive layer is coated with the release film layer;

[0037] or,

[0038] Applying glue corresponding to the first pressure-sensitive adhesive layer on the base film layer, thermally curing to obtain the first pressure-sensitive adhesive layer, and laminating the first pressure-sensitive adhesive layer with a first release film;

[0039] coating a coating corresponding to the thermoplastic polyurethane elastomer layer on the second release film, thermally curing the coating to obtain the thermoplastic polyurethane elastomer layer, and laminating the thermoplastic polyurethane elastomer layer with a third release film;

[0040] The third release film on the thermoplastic polyurethane elastomer layer is removed, and then a layer of glue corresponding to the second pressure-sensitive layer is coated on the thermoplastic polyurethane elastomer layer, and thermally cured to obtain a second pressure-sensitive adhesive layer, and the second pressure-sensitive adhesive layer is coated with a release film layer.

[0041] The second release film on the thermoplastic polyurethane elastomer layer is removed, and then a layer of self-repairing coating is coated on the thermoplastic polyurethane elastomer layer, and a self-repairing layer is obtained by heat curing and ultraviolet curing;

[0042] The first release film on the first pressure-sensitive adhesive layer is torn off, and the self-repairing layer is coated with the first pressure-sensitive adhesive layer and cured.

[0043] In the above technical scheme, the second release film is used as a carrier for coating the corresponding coating of the thermoplastic polyurethane elastomer layer. After the thermoplastic polyurethane elastomer layer is formed, it is coated with the third release film to effectively protect the appearance of the thermoplastic polyurethane elastomer layer; the first release film is used to protect the first pressure-sensitive adhesive layer to prevent foreign matter from adhering to it and affecting the appearance and viscosity of the first pressure-sensitive adhesive layer; the self-healing coating is coated on the thermoplastic polyurethane elastomer layer to form a self-healing layer, which is covered with an upper protective layer composed of a low-viscosity first pressure-sensitive adhesive layer and a base film layer to protect the self-healing layer, and then ripened to allow the unreacted thermosetting small molecules in each layer to continue to react during the ripening process; the release film layer is used to protect the second pressure-sensitive adhesive layer to prevent foreign matter from adhering to it and affecting the appearance and viscosity of the second pressure-sensitive adhesive layer.

[0044] In one possible implementation, the temperature of thermal curing is 110-155°C, and the energy of UV curing is 1000-2000 mJ / cm 2 ;

[0045] And / or, the coating is performed by blade coating or slit coating in all steps. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0047] Figure 1 A schematic diagram of the structure of an electronic screen protective film provided in an embodiment of the present application.

[0048] Icon: 100 - electronic screen protective film; 110 - base film layer; 120 - first pressure-sensitive adhesive layer; 130 - self-healing layer; 140 - thermoplastic polyurethane elastomer layer; 150 - second pressure-sensitive adhesive layer; 160 - release film layer. DETAILED DESCRIPTION

[0049] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to the conventional conditions or the conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0050] The self-repairing coating, electronic screen protective film and preparation method of the embodiments of the present application are described in detail below.

[0051] An embodiment of the present application provides a self-healing coating, the components of which include, by weight: 60-70 parts of linear aliphatic polycarbonate polyol, 20-30 parts of hydroxyl polyester, 90-110 parts of dual-cure resin, 40-50 parts of acrylate, 60-70 parts of ketone-aldehyde resin, 35-45 parts of aliphatic isocyanate, 1-1.5 parts of free radical photoinitiator, 0.05-0.15 parts of non-organic tin catalyst, 1-5 parts of lubricant, and 170-210 parts of solvent. Exemplarily, the components of the self-healing coating include, by weight: 60, 62, 65, 68 or 70 parts of linear aliphatic polycarbonate polyol, 20, 23, 25, 27 or 30 parts of hydroxy polyester, 90, 100 or 110 parts of dual-cure resin, 40, 41, 43, 45, 47 or 50 parts of acrylate, 60, 62, 65, 68 or 70 parts of ketone-aldehyde resin, 35, 38, 40 or 45 parts of aliphatic isocyanate, 1, 1.2, 1.35 or 1.5 parts of free radical photoinitiator, 0.05, 0.1 or 0.15 parts of non-organotin catalyst, 1, 3 or 5 parts of lubricant, and 170, 180, 190, 200 or 210 parts of solvent.

[0052] In the present application, the specific selection of each component is as follows:

[0053] Linear aliphatic polycarbonate polyols are a type of polymers containing repeated carbonate groups (-O-COO-) in the main chain of the molecule and hydroxyl groups (-OH) at the chain end. The options include Covestro Desmophen C 1100 of Covestro Polymers (China) Co., Ltd., Covestro Desmophen C 1200 of Covestro Polymers (China) Co., Ltd., Desmophen C2200 (linear polycarbonate diol) of Covestro Polymers (China) Co., Ltd., Desmophen C2100 (linear polycarbonate diol) of Covestro Polymers (China) Co., Ltd., and "Duracell" of Asahi Kasei. TM " (polycarbonate diol) at least one.

[0054] The hydroxy polyester is obtained by a dehydration esterification reaction of a dibasic acid with an excess of a polyol, and can be selected from at least one of Desmophen 670BA of Covestro Polymers (China) Co., Ltd., Desmophen 651 MPA / X of Covestro Polymers (China) Co., Ltd., H101 of the HyPer H10 series of Suzhou Haibote Resin Technology Co., Ltd., H103 of the HyPer H10 series of Suzhou Haibote Resin Technology Co., Ltd., and H104 of the HyPer H10 series of Suzhou Haibote Resin Technology Co., Ltd.

[0055] Dual-cure resin is a polymer that can be thermally cured and light-cured, and can specifically be modified polyurethane acrylate with high hardness. It can be selected from at least one of 1831A of Guangdong Dinglisen New Materials Co., Ltd., 1443 of Guangdong Dinglisen New Materials Co., Ltd., D-039 of Changzhou Sante Chemical Co., Ltd., HUV-201A of Suzhou Hangzhi New Materials Co., Ltd., and dual-stage curing coating DHC-92L of Guangzhou Tetrahedron New Materials Technology Co., Ltd.

[0056] Acrylate is a general term for acrylic acid and its homologues, and its molecular structure has high polarity and complete saturation. It can be selected from at least one of A-NOD-N of Shin-Nakamura Chemical Industry Co., Ltd., A-HD-N of Shin-Nakamura Chemical Industry Co., Ltd., 1,4-cyclohexanedimethanol diacrylate of Guangdong Huiquan Lianjun Chemical Industry Co., Ltd., polyethylene glycol diacrylate (n=4) of Guangdong Huiquan Lianjun Chemical Industry Co., Ltd., ethoxylated trimethylolpropane triacrylate of Guangdong Huiquan Lianjun Chemical Industry Co., Ltd., and caprolactone acrylate of Youming (Shanghai) Chemical Co., Ltd.

[0057] Ketone-aldehyde resin is a neutral, non-saponifiable cyclohexanone with high brightness and light resistance, and KR-1021 of Anfeng Industrial Technology Co., Ltd. can be selected.

[0058] Aliphatic isocyanate refers to isocyanate products other than aromatic isocyanate, which has a -N=CO functional group. The polyurethane material prepared with aliphatic isocyanate has good anti-aging, high temperature resistance, yellowing resistance, light resistance and other properties. The aliphatic isocyanate can be selected from at least one of isophorone diisocyanate, hexamethylene diisocyanate, 4'-diisocyanate, methylcyclohexane diisocyanate, trimethylhexamethylene diisocyanate and xylylene diisocyanate.

[0059] The free radical photoinitiator may be a benzophenone derivative.

[0060] The non-organotin catalyst is a catalyst other than an organotin catalyst, and can be selected from at least one of Valikat Bi2810, TMG 160 of Shanghai Manhai Gaoschmidt Chemical Co., Ltd., TMG 720 of Shanghai Manhai Gaoschmidt Chemical Co., Ltd., TMG 634 of Haiman Haigao Schmidt Chemical Co., Ltd., TMG 612 of Haiman Haigao Schmidt Chemical Co., Ltd., and TMG 330 of Haiman Haigao Schmidt Chemical Co., Ltd.

[0061] The lubricant is a highly compatible, highly cross-linked lubricant that can effectively increase the water contact angle of the film. Specifically, it can be silicone acrylate, and Evonik's TEGO Rad2250 can be selected.

[0062] The solvent is at least one of methyl isobutyl ketone, ethyl acetate, methyl acetate, propyl acetate, methyl isobutyl ketone, toluene, xylene, cyclohexane, 120# solvent, cyclohexanone and isopropanol.

[0063] See also Figure 1 As shown, the embodiment of the present application also provides an electronic screen protective film 100, which includes: a base film layer 110, a first pressure-sensitive adhesive layer 120, a self-healing layer 130, a thermoplastic polyurethane elastomer layer 140, a second pressure-sensitive adhesive layer 150 and a release film layer 160 stacked in sequence from top to bottom; wherein, the base film layer 110 and the first pressure-sensitive adhesive layer 120 constitute an upper protective layer. When in use, the release film layer 160 of the electronic screen protective film 100 is torn off, the second pressure-sensitive adhesive layer 150 is attached to the electronic screen (such as the curved screen of a curved mobile phone), and then the upper protective layer is torn off.

[0064] The self-repairing layer 130 is obtained by coating, thermally curing, and ultraviolet curing the above-mentioned self-repairing coating.

[0065] Among them, the thermoplastic polyurethane elastomer layer 140 is obtained by coating and thermally curing the corresponding coating. As an embodiment, the components of the corresponding coating of the thermoplastic polyurethane elastomer layer 140 include, by weight: 100 parts by weight of aliphatic polyurethane acrylic resin (AA4835 of Eurasia Enterprise Co., Ltd.), 10-20 parts by weight of TPU particles (Lubrizol's 5715), 80-100 parts by weight of ketone-aldehyde resin (KR-1021 of Anfeng Industrial Co., Ltd.), 25-30 parts by weight of butanone, 50-55 parts by weight of cyclohexanone, 0.3-0.5 parts by weight of polyester-modified hydroxyl-functional polydimethylsiloxane solution (BYK Chemical, BYK-371), and 10-20 parts by weight of high-functionality HDI trimer (Covestro, aliphatic polyisocyanate series, N3700) are mixed to obtain TPU composite glue.

[0066] Among them, the first pressure-sensitive adhesive layer 120 is obtained by coating and heat curing with corresponding glue. As an embodiment, the components of the corresponding glue of the first pressure-sensitive adhesive layer 120 include by weight: 45-50 parts of polyurethane resin, 3-5 parts of isocyanate curing agent, 0.3-2 parts of antistatic agent, and 45-50 parts of solvent. The first pressure-sensitive adhesive is a PU adhesive system, which is used to protect the self-repairing layer. The peeling force is small, 2-4gf / 25mm for steel plate, 0.5-2gf / 25mm for tearing film before baking the self-repairing layer, and 1.5-4gf / 25mm for tearing film after baking.

[0067] Among them, the second pressure-sensitive adhesive layer 150 is obtained by coating and heat curing the corresponding glue. As an implementation method, the components of the corresponding glue of the second pressure-sensitive adhesive layer 150 include by weight: 100 parts of silicone resin, 0.5-2 parts of reactive polysiloxane, 0.5-2 parts of silane coupling agent, 1-3 parts of platinum catalyst, and 80-200 parts of solvent. The second pressure-sensitive adhesive is a silicone system, which is used to attach the AF cover plate on the client. The AF cover plate has a high water contact angle (118-120°), so the second pressure-sensitive adhesive is required to have a large AF peeling force (≥40gf / 25mm).

[0068] The base film layer 110 may be a PET film; and the release film layer 160 may be a fluorine release film.

[0069] The embodiment of the present application provides a method for preparing the above-mentioned electronic screen protective film 100, which comprises the following steps:

[0070] A first pressure-sensitive adhesive layer 120 is disposed on the base film layer 110;

[0071] The self-repairing layer 130 , the second pressure-sensitive adhesive layer 150 , and the release film layer 160 are respectively disposed on both sides of the thermoplastic polyurethane elastomer layer 140 , so that the first pressure-sensitive adhesive layer 120 and the self-repairing layer 130 are laminated and compounded together.

[0072] As an implementation method, it specifically includes the following steps:

[0073] (1) A glue corresponding to the first pressure-sensitive adhesive layer 120 is coated on the base film layer 110, and the first pressure-sensitive adhesive layer 120 is obtained by thermal curing, and the first pressure-sensitive adhesive layer 120 is coated with a first release film.

[0074] (2) coating a coating material corresponding to the thermoplastic polyurethane elastomer layer 140 on the second release film, and thermally curing the coating material to obtain the thermoplastic polyurethane elastomer layer 140 , and laminating the thermoplastic polyurethane elastomer layer 140 with a third release film.

[0075] (3) The second release film on the thermoplastic polyurethane elastomer layer 140 is removed, and then a layer of self-healing coating is coated on the thermoplastic polyurethane elastomer layer 140, and the self-healing layer 130 is obtained by heat curing and UV curing. In the above technical scheme, the dual-cured self-healing layer 130, heat curing + UV curing, can be carried out simultaneously or separately, such as heat curing first and then UV curing.

[0076] It should be noted that there is no special requirement for the order of step (1) and step (2)-step (3), and the two can be performed one after the other or simultaneously.

[0077] (4) The first release film on the first pressure-sensitive adhesive layer 120 is removed, and the self-repairing layer 130 is coated with the first pressure-sensitive adhesive layer 120 and cured.

[0078] It should be noted that after aging, the thermosetting molecules in each film layer will continue to react, so each film layer after aging truly becomes the corresponding film layer in the protective film.

[0079] (5) The third release film on the thermoplastic polyurethane elastomer layer 140 is removed, and a layer of glue corresponding to the second pressure-sensitive layer is coated on the thermoplastic polyurethane elastomer layer 140 , and the second pressure-sensitive adhesive layer 150 is obtained by thermal curing, and the second pressure-sensitive adhesive layer 150 is coated with a release film layer 160 .

[0080] As another embodiment, the following steps can also be used to prepare:

[0081] (1) coating a glue corresponding to the first pressure-sensitive adhesive layer 120 on the base film layer 110, thermally curing to obtain the first pressure-sensitive adhesive layer 120, and laminating the first pressure-sensitive adhesive layer with a first release film;

[0082] (2) coating a coating corresponding to the thermoplastic polyurethane elastomer layer 140 on the second release film, thermally curing the coating to obtain the thermoplastic polyurethane elastomer layer 140, and laminating the thermoplastic polyurethane elastomer layer with a third release film;

[0083] (3) The third release film on the thermoplastic polyurethane elastomer layer 140 is removed, and a layer of glue corresponding to the second pressure-sensitive layer 150 is coated on the thermoplastic polyurethane elastomer layer 140 , and thermally cured to obtain the second pressure-sensitive adhesive layer 150 , and the second pressure-sensitive adhesive layer 150 is coated with a release film layer 160 .

[0084] (4) tearing off the second release film 140 on the thermoplastic polyurethane elastomer layer, and then coating a layer of self-repairing coating on the thermoplastic polyurethane elastomer layer 140, and obtaining the self-repairing layer 130 through thermal curing and UV curing;

[0085] (5) The first release film on the first pressure-sensitive adhesive layer 120 is removed, and the self-healing layer 130 is coated with the first pressure-sensitive adhesive layer 120 and cured.

[0086] In the above preparation process, the first release film, the second release film and the third release film are usually silicone release films, and the release film in the protective film is usually a fluorine release film.

[0087] In all the above steps, the temperature of thermal curing is 110-155℃; the energy of UV curing is 1000-2000mJ / cm 2 In all steps, coating can be performed by blade coating or slot coating.

[0088] The features and performance of the present application are further described in detail below in conjunction with the embodiments.

[0089] Example 1

[0090] The present embodiment provides a self-healing protective film for a curved mobile phone, which includes: a base film layer, a first pressure-sensitive adhesive layer, a self-healing layer, a thermoplastic polyurethane elastomer layer, a second pressure-sensitive adhesive layer and a release film layer stacked in sequence from top to bottom, wherein the base film layer + the first pressure-sensitive adhesive = the upper protective layer.

[0091] The material components of the glue corresponding to the first pressure-sensitive adhesive layer are: 48 parts by weight of polyurethane resin (KT-9005, KT of South Korea), 1 part by weight of antistatic agent (GT-100F, Shanghai Gutong Technology Co., Ltd.), 3.8 parts by weight of isocyanate curing agent (NA-220, Shanghai Gutong Technology Co., Ltd.) and 46.6 parts by weight of ethyl acetate, and the above material components are mixed and stirred evenly.

[0092] The material components of the self-repairing layer corresponding to the self-repairing coating are: 65 parts by weight of linear aliphatic polycarbonate polyol ( C 1100, Guangzhou Haoyi New Material Technology Co., Ltd.), 25 parts by weight of hydroxy polyester ( 670BA, Guangzhou Haoyi New Material Technology Co., Ltd.), 100 parts by weight of dual-cure resin (DSU-1831A, Guangdong Dinglisen New Material Co., Ltd.), 45 parts by weight of acrylate (A-NOD-N, Shin-Nakamura Chemical Industry Co., Ltd.), 65 parts by weight of ketone-aldehyde resin (KR-1021, Anfeng Industrial Technology Co., Ltd.), 1.35 parts by weight of free radical photoinitiator (benzophenone derivative), 0.1 parts by weight of non-organic tin catalyst (TMG 160, Shanghai Manhai Gao Schmidt Chemical Co., Ltd.), 40 parts by weight of aliphatic isocyanate ( N 3700, Guangzhou Haoyi New Material Technology Co., Ltd.), 3 parts by weight of a lubricant (TEGO Rad 2250, Evonik), 150 parts by weight of methyl isobutyl ketone and 40 parts by weight of ethyl acetate, and the above material components are mixed and stirred to obtain a product.

[0093] The material components of the coating corresponding to the thermoplastic polyurethane elastomer layer are: 100 parts by weight of aliphatic polyurethane acrylic resin (AA4835 of Eurasia Enterprise Co., Ltd.), 15 parts by weight of TPU particles (Lubrizol's 5715), 90 parts by weight of ketone-aldehyde resin (KR-1021 of Anfeng Industrial Co., Ltd.), 28 parts by weight of butanone, 52 parts by weight of cyclohexanone, 0.4 parts by weight of polyester-modified hydroxyl-functional polydimethylsiloxane solution (BYK Chemical, BYK-371), 15 parts by weight of high-functionality HDI trimer (Covestro, aliphatic polyisocyanate series, N3700), and the above material components are mixed and stirred evenly.

[0094] The material components of the glue corresponding to the second pressure-sensitive adhesive layer are: 100 parts by weight of silicone resin (30500HP, Jiangsu Kunshan Prekai Nanotechnology Co., Ltd.), 0.6 parts by weight of vinyl silane mixed liquid (S-506, Jiangsu Kunshan Prekai Nanotechnology Co., Ltd.), 0.6 parts by weight of reactive polysiloxane (H-7316, Jiangsu Kunshan Prekai Nanotechnology Co., Ltd.), 1.2 parts by weight of platinum catalyst (SYL-OFF TM 4000, Shi Chemical), 70 parts by weight of 120# solvent and 30 parts by weight of ethyl acetate, the above material components are mixed and stirred evenly to obtain the product.

[0095] The specific preparation method is as follows:

[0096] (1) A first pressure-sensitive adhesive layer was coated with glue corresponding to a 50 μm thick PET film (base film layer), and baked at 120° C. for 2 minutes to obtain a 10 μm thick first pressure-sensitive adhesive layer, and the first pressure-sensitive adhesive layer was coated with a 50 μm silicone release film (first release film).

[0097] (2) A coating corresponding to the thermoplastic polyurethane elastomer layer is coated on a 50 μm thick silicone release film (second release film), and the coating is baked at 120° C. for 2 minutes to obtain a 75 μm thick thermoplastic polyurethane elastomer layer, and the thermoplastic polyurethane elastomer layer is coated with a 75 μm thick silicone release film (third release film).

[0098] (3) Remove the second release film on the thermoplastic polyurethane elastomer layer, apply the self-healing coating on the thermoplastic polyurethane elastomer layer, and bake at 115°C for 2 minutes and 1000 mJ / cm 2 A 35 μm thick self-healing layer was obtained under UV energy.

[0099] (4) The first release film on the first pressure-sensitive adhesive layer was removed, and the self-repairing layer was adhered to the first pressure-sensitive adhesive layer, followed by curing at 40° C. for 5 days.

[0100] (5) Tear off the third release film on the thermoplastic polyurethane elastomer layer, apply the glue corresponding to the second pressure-sensitive layer on the thermoplastic polyurethane elastomer layer, bake at 150° C. for 2 minutes to obtain a 15 μm thick second pressure-sensitive adhesive layer, and coat the second pressure-sensitive adhesive layer with a fluorine release film (release film layer).

[0101] When in use, tear off the fluorine release film of the self-repairing protective film, stick the second pressure-sensitive adhesive layer on the curved screen of the curved mobile phone, and tear off the upper protective layer.

[0102] Example 2

[0103] The present embodiment provides a protective film, which differs from Embodiment 1 in that the material components of the glue corresponding to the second pressure-sensitive adhesive layer are different. In the present embodiment, the material components of the glue corresponding to the second pressure-sensitive adhesive layer are: 50 parts by weight of silicone resin (AP-7360F, Anpin), 50 parts by weight of silicone resin (AP-7380F, Jiangsu Kunshan Purukai Nanotechnology Co., Ltd.), 1 part by weight of vinyl silane mixture (297, Anpin), 0.8 parts by weight of reactive polysiloxane (H-7316, Jiangsu Kunshan Purukai Nanotechnology Co., Ltd.), 1.44 parts by weight of platinum catalyst (Dow Chemical), 50 parts by weight of toluene and 50 parts by weight of ethyl acetate.

[0104] Example 3

[0105] This embodiment provides a protective film, which differs from Embodiment 1 in the preparation steps. The specific preparation method is as follows:

[0106] (1) A first pressure-sensitive adhesive layer was coated with glue corresponding to a 50 μm thick PET film (base film layer), and baked at 120° C. for 2 minutes to obtain a 10 μm thick first pressure-sensitive adhesive layer, and the first pressure-sensitive adhesive layer was coated with a 50 μm silicone release film (first release film).

[0107] (2) A coating corresponding to the thermoplastic polyurethane elastomer layer is coated on a 50 μm thick silicone release film (second release film), and the coating is baked at 120° C. for 2 minutes to obtain a 75 μm thick thermoplastic polyurethane elastomer layer, and the thermoplastic polyurethane elastomer layer is coated with a 75 μm thick silicone release film (third release film).

[0108] (3) Tear off the third release film on the thermoplastic polyurethane elastomer layer, apply the glue corresponding to the second pressure-sensitive layer on the thermoplastic polyurethane elastomer layer, bake at 150° C. for 2 minutes to obtain a 15 μm thick second pressure-sensitive adhesive layer, and coat the second pressure-sensitive adhesive layer with a fluorine release film (release film layer).

[0109] (4) Remove the second release film on the thermoplastic polyurethane elastomer layer, apply the self-healing coating on the thermoplastic polyurethane elastomer layer, and bake at 115°C for 2 minutes and 1000 mJ / cm 2 A 35 μm thick self-healing layer was obtained under UV energy.

[0110] (5) The first release film on the first pressure-sensitive adhesive layer was removed, and the self-repairing layer was adhered to the first pressure-sensitive adhesive layer, followed by aging at 40° C. for 5 days.

[0111] When in use, tear off the fluorine release film of the self-repairing protective film, stick the second pressure-sensitive adhesive layer on the curved screen of the curved mobile phone, and tear off the upper protective layer.

[0112] Comparative Example 1

[0113] This comparative example provides a protective film, which is different from Example 1 in that: this comparative example does not have a self-repairing layer, and the thickness of the thermoplastic polyurethane elastomer layer is 110 μm. The specific preparation method is as follows:

[0114] (1) A first pressure-sensitive adhesive layer was coated with glue corresponding to a 50 μm thick PET film (base film layer), and baked at 120° C. for 2 minutes to obtain a 10 μm thick first pressure-sensitive adhesive layer, and the first pressure-sensitive adhesive layer was coated with a 50 μm silicone release film (first release film).

[0115] (2) A coating corresponding to the thermoplastic polyurethane elastomer layer is coated on a 50 μm thick silicone release film (second release film), and the film is baked at 120° C. for 2 minutes to obtain a 110 μm thick thermoplastic polyurethane elastomer layer. The first release film on the first pressure-sensitive adhesive layer is removed, and the thermoplastic polyurethane elastomer layer is bonded to the first pressure-sensitive adhesive layer.

[0116] (3) Tear off the second release film on the thermoplastic polyurethane elastomer layer, apply the glue corresponding to the second pressure-sensitive layer on the thermoplastic polyurethane elastomer layer, bake at 150° C. for 2 minutes to obtain a 15 μm thick second pressure-sensitive adhesive layer, and coat the second pressure-sensitive adhesive layer with a fluorine release film (release film layer).

[0117] When in use, tear off the fluorine release film of the protective film, stick the second pressure-sensitive adhesive layer on the curved screen of the curved mobile phone, and tear off the upper protective layer.

[0118] Comparative Example 2

[0119] This comparative example provides a protective film, which is different from Example 1 in that: this comparative example does not have a thermoplastic polyurethane elastomer layer, and the thickness of the self-repairing layer is 110 μm. The specific preparation method is as follows:

[0120] (1) A first pressure-sensitive adhesive layer was coated with glue corresponding to a 50 μm thick PET film (base film layer), and baked at 120° C. for 2 minutes to obtain a 10 μm thick first pressure-sensitive adhesive layer, and the first pressure-sensitive adhesive layer was coated with a 50 μm silicone release film (first release film).

[0121] (2) A self-healing coating was applied on a 50 μm thick silicone release film (second release film) and baked at 115°C for 2 minutes at 1000 mJ / cm 2 A 110 μm thick self-healing layer was obtained under UV energy.

[0122] (3) The first release film on the first pressure-sensitive adhesive layer was removed, and the self-repairing layer was adhered to the first pressure-sensitive adhesive layer, followed by curing at 40° C. for 5 days.

[0123] (4) Tear off the second release film on the self-repairing coating, apply the glue corresponding to the second pressure-sensitive layer on the self-repairing coating, bake at 150° C. for 2 minutes to obtain a 15 μm thick second pressure-sensitive adhesive layer, and coat the second pressure-sensitive adhesive layer with a fluorine release film (release film layer).

[0124] When in use, tear off the fluorine release film of the protective film, stick the second pressure-sensitive adhesive layer on the curved screen of the curved mobile phone, and tear off the upper protective layer.

[0125] Comparative Example 3

[0126] This comparative example provides a protective film, which is different from Example 1 in that: the material components of the self-repairing layer of this comparative example corresponding to the self-repairing coating do not contain acrylate, and the weight portion of the ketone-aldehyde resin is 110 parts by weight.

[0127] Comparative Example 4

[0128] This comparative example provides a protective film, which is different from Example 1 in that: the self-repairing layer of this comparative example corresponds to the material component of the self-repairing coating without adding hydroxyl polyester.

[0129] Comparative Example 5

[0130] This comparative example provides a protective film, which is different from Example 1 in that no lubricant is added to the material components of the self-repairing layer corresponding to the self-repairing coating in this comparative example.

[0131] Performance testing and testing methods

[0132] 1. Offset printing test:

[0133] The specific method is: stick the protective film on the TP glass (AF screen, water drop angle>110±5°), remove the upper protective layer, cut the Mitsubishi HB pencil lead into a 5mm cylinder and grind it on 400-grit sandpaper, install it on the pencil hardness tester, apply a load of 200g on the pencil hardness tester, the angle between the pencil and the surface of the protective film is 45°, push the pencil forward at a constant speed for about 5mm at the position to be tested, and make 5 strokes at different positions. If there is no scratch on the surface of the protective film or the scratch can be restored within 60s, it is judged as qualified (OK), otherwise it is unqualified (NG).

[0134] 2. AF peeling force test:

[0135] The specific method is as follows: the protective film is cut into samples with a width of 25mm±1mm and a length of about 200mm, and the samples are pasted in the middle position of the TP glass in the longitudinal direction parallel to the TP glass (AF screen, water drop angle>110±5°), and a roller is used to roll back and forth on the TP glass three times at a speed of about 300mm / min under its own weight (no bubbles or wrinkles are allowed between the sample and the TP glass), and the upper protective layer is removed, and then it is placed in a test environment and left to stand for 20 minutes, and then tested with a tension and pressure testing machine at a speed of 300mm / min, and the peeling force data is recorded, and the test is repeated 5 times in succession to take the average value.

[0136] 3. Upper insulation layer self-separation test:

[0137] The specific method is: stick the protective film on the TP glass (AF screen, water drop angle > 110±5°), observe and record the time for the upper protective layer on the curved surface of the TP glass to bounce back. If the time is less than 3 seconds, it is judged as qualified (OK), otherwise it is judged as unqualified (NG).

[0138] 4. Copper brush test (self-repair ability):

[0139] The specific method is: install a special copper brush (Japan OSAKA JAPAN OK copper brush, the brush head is 4*6 groups of bristles) on the wear tester, apply a force of 500gf in the vertical direction, rub the surface of the protective film 20 times (test frequency: 35-50 times / minute, forming 30-50mm), avoid the edge of the protective film when rubbing, and count the number of scratches within 60s. If the number of scratches is ≤5, it is qualified (OK), otherwise it is judged as unqualified (NG).

[0140] 5. High temperature and high humidity test:

[0141] The specific method is: stick the protective film on TP glass (AF screen, water drop angle>110±5°), remove the upper protective layer, and then place it in a constant temperature and humidity test chamber at a temperature of 60±2℃ and a humidity of 90±2%RH for 72 hours. After taking it out, let it stand at room temperature (25±5℃, 65±10%RH) for 12 hours, and then observe the appearance of the protective film. If there is no discoloration, cracks, delamination, degumming, bubbles or warping of the curved surface on the surface of the protective film, it is judged as qualified (OK). On the contrary, if there is any discoloration, cracks, delamination, degumming, bubbles or warping of the curved surface on the surface, it is judged as unqualified (NG).

[0142] 6. Cosmetic adsorption test:

[0143] Stick the protective film on the TP glass (AF screen, water drop angle > 110±5°), remove the upper protective layer, dip the cosmetics (LIDEAL brand blush) with a cotton pad and evenly apply it on the protective film. After standing for 1 hour, wipe it 5 times with a dust-free cloth. If there is no obvious residue visually after wiping, it is judged as qualified (OK), otherwise it is judged as unqualified (NG).

[0144] 7. Dust adsorption test:

[0145] Use a new felt (EMPA701 white) with a size of 15*15mm and load it with 500gf. Perform friction test on the sample surface 50 times. After the test, take photos and record them at a distance of 10-15cm from the test position. Use VSG010302 integrated air blower to pressurize and blow air to the test area 15cm above this position twice to check the residual wool state on the surface. Observe from a distance of 10-15cm from the test sample. If there is no obvious residue visually, it is judged as qualified (OK), otherwise it is judged as unqualified (NG).

[0146] Table 1 Test results

[0147]

[0148]

[0149] Comparing the test results of Example 1 and Comparative Example 1, the protective film of Comparative Example 1 has no self-repairing layer. Although the thermoplastic polyurethane elastomer has good recovery properties, its hardness is poor. The offset printing and copper brush tests fail NG. The water contact angle of the thermoplastic polyurethane is low. The tearing force data of the upper protection film is large. The upper protection self-separation function cannot be achieved when it is bonded to the curved surface of the mobile phone. The cosmetics adsorption test and the dust adsorption test fail NG.

[0150] Comparing the test results of Example 1 and Comparative Example 2, the protective film of Comparative Example 2 has no thermoplastic polyurethane elastomer layer. In the offset printing test, the offset printing test recovers slowly and fails the offset printing test NG.

[0151] Comparing the test results of Example 1 and Comparative Example 3, no acrylate was added to the self-repairing component of Comparative Example 3, and the content of ketone-aldehyde resin was increased. The ketone-aldehyde resin molecular structure contains a carbonyl group and a hydroxyl terminal group, which has good compatibility with the self-repairing resin and can effectively improve the initial drying, chemical resistance and weather resistance of the self-repairing coating. However, the ketone-aldehyde resin does not participate in the chemical crosslinking process of film formation in the self-repairing coating, but only acts as a physical film-forming material. Acrylate directly participates in the chemical crosslinking during the thermal photocuring process of the self-repairing layer, giving the self-repairing layer a higher hardness. Adding excessive ketone-aldehyde resin and not adding acrylate will affect the hardness of the self-repairing layer, resulting in NG in the offset test and the copper brush test.

[0152] Comparing the test results of Example 1 and Comparative Example 4, the self-repairing layer component of Comparative Example 4 does not contain hydroxyl polyester, which can improve the strength and toughness of the self-repairing layer.

[0153] Comparing the test results of Example 1 and Comparative Example 5, the self-repairing layer of Comparative Example 5 does not contain a lubricant, the water contact angle of the self-repairing layer is reduced, and the upper film tearing force is increased, resulting in failures of the upper film self-separation test, the cosmetics adsorption test and the dust adsorption test.

[0154] In summary, the self-repairing coating, electronic screen protective film and preparation method of the embodiments of the present application have good offset printing, excellent self-repairing ability, and can ensure the self-repairing effect for a long time, and can be used under extreme conditions.

[0155] The above description is only an embodiment of the present application and is not intended to limit the protection scope of the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A self-repairing coating, characterized in that: Its components include by weight: 60-70 parts of linear aliphatic polycarbonate polyol; 20-30 parts of hydroxy polyester; Dual-curing resin 90-110 parts; Acrylate 40-50 parts; 60-70 parts of ketone-aldehyde resin; Aliphatic isocyanate 35-45 parts; 1-1.5 parts of free radical photoinitiator; 0.05-0.15 parts of non-organic tin catalyst; 1-5 parts of lubricant; 170-210 parts of solvent; The dual-cure resin is modified polyurethane acrylate, and the dual-cure resin is at least one of 1831A and 1443 of Guangdong Dinglisen New Materials Co., Ltd., D-039 of Changzhou Sante Chemical Co., Ltd., HUV-201A of Suzhou Hangzhi New Materials Co., Ltd., and dual-stage curing coating DHC-92L of Guangzhou Tetrahedron New Materials Technology Co., Ltd.; The linear aliphatic polycarbonate polyol is at least one of Desmophen C1100, Desmophen C1200, Desmophen C2200 and Desmophen C2100 of Covestro Polymers Co., Ltd. The acrylate is at least one of A-NOD-N and A-HD-N of Shin-Nakamura Chemical Co., Ltd., 1,4-cyclohexanedimethanol diacrylate, polyethylene glycol diacrylate, ethoxylated trimethylolpropane triacrylate, and caprolactone acrylate.

2. The self-repairing coating according to claim 1, characterized in that: The hydroxy polyester is at least one of Desmophen 670 BA, Desmophen 651 MPA / X of Covestro Polymer Co., Ltd., and H101, H103, and H104 of the HyPerH10 series of Suzhou Haibote Resin Technology Co., Ltd.

3. The self-repairing coating according to claim 1, characterized in that: The ketone-aldehyde resin is KR-1021 produced by Anfeng Industrial Technology Co., Ltd. and / or, the aliphatic isocyanate is at least one of isophorone diisocyanate, hexamethylene diisocyanate, 4'-diisocyanate, methylcyclohexane diisocyanate, trimethylhexamethylene diisocyanate and xylylene diisocyanate; and / or, the free radical photoinitiator is a benzophenone derivative; And / or, the non-organotin catalyst is at least one of Valikat Bi2810, TMG 160, TMG 720, TMG 634, TMG 612, and TMG 330 of Shanghai Manhai Gaoschmidt Chemical Co., Ltd.; And / or, the lubricant is TEGO Rad 2250 produced by Evonik; And / or, the solvent is at least one of methyl isobutyl ketone, ethyl acetate, methyl acetate, propyl acetate, toluene, xylene, cyclohexane, 120# solvent, cyclohexanone and isopropanol.

4. An electronic screen protective film, characterized in that: It includes: a base film layer, a first pressure-sensitive adhesive layer, a self-healing layer, a thermoplastic polyurethane elastomer layer, a second pressure-sensitive adhesive layer and a release film layer stacked in sequence from top to bottom, wherein the self-healing layer is obtained by coating, thermally curing or ultraviolet curing the self-healing coating as described in any one of claims 1 to 3.

5. The electronic screen protective film according to claim 4, characterized in that: The components of the first pressure-sensitive adhesive layer corresponding to the glue include, by weight: 45-50 parts of polyurethane resin; 3-5 parts of isocyanate curing agent; Antistatic agent 0.3-2 parts 45-50 parts of solvent; And / or, the components of the glue corresponding to the second pressure-sensitive adhesive layer include, by weight: 100 parts of silicone resin; Reactive polysiloxane 0.5-2 parts; Silane coupling agent 0.5-2 parts; 1-3 parts of platinum catalyst; 80-200 parts of solvent.

6. A method for preparing an electronic screen protective film as claimed in claim 4 or 5, characterized in that: It includes the following steps: Disposing a first pressure-sensitive adhesive layer on the base film layer; A self-repairing layer, a second pressure-sensitive adhesive layer and a release film layer are respectively arranged on both sides of the thermoplastic polyurethane elastomer layer, so that the first pressure-sensitive adhesive layer and the self-repairing layer are laminated and compounded together.

7. The method for preparing the electronic screen protective film according to claim 6, characterized in that: It includes the following steps: Applying glue corresponding to the first pressure-sensitive adhesive layer on the base film layer, thermally curing to obtain a first pressure-sensitive adhesive layer, and laminating the first pressure-sensitive adhesive layer with a first release film; coating a coating corresponding to the thermoplastic polyurethane elastomer layer on the second release film, thermally curing the coating to obtain a thermoplastic polyurethane elastomer layer, and laminating the thermoplastic polyurethane elastomer layer with a third release film; The second release film on the thermoplastic polyurethane elastomer layer is removed, and a layer of self-repairing coating is coated on the thermoplastic polyurethane elastomer layer, and a self-repairing layer is obtained by heat curing and ultraviolet curing; removing the first release film on the first pressure-sensitive adhesive layer, laminating the self-repairing layer with the first pressure-sensitive adhesive layer, and curing the layer; The third release film on the thermoplastic polyurethane elastomer layer is removed, and a layer of glue corresponding to the second pressure-sensitive layer is coated on the thermoplastic polyurethane elastomer layer, and the second pressure-sensitive adhesive layer is obtained by thermal curing, and the second pressure-sensitive adhesive layer is coated with a release film layer; or, Applying glue corresponding to the first pressure-sensitive adhesive layer on the base film layer, thermally curing to obtain a first pressure-sensitive adhesive layer, and laminating the first pressure-sensitive adhesive layer with a first release film; coating a coating corresponding to the thermoplastic polyurethane elastomer layer on the second release film, thermally curing the coating to obtain a thermoplastic polyurethane elastomer layer, and laminating the thermoplastic polyurethane elastomer layer with a third release film; The third release film on the thermoplastic polyurethane elastomer layer is removed, and a layer of glue corresponding to the second pressure-sensitive layer is coated on the thermoplastic polyurethane elastomer layer, and the second pressure-sensitive adhesive layer is obtained by thermal curing, and the second pressure-sensitive adhesive layer is coated with a release film layer; The second release film on the thermoplastic polyurethane elastomer layer is removed, and a layer of self-repairing coating is coated on the thermoplastic polyurethane elastomer layer, and a self-repairing layer is obtained by heat curing and ultraviolet curing; The first release film on the first pressure-sensitive adhesive layer is removed, and the self-repairing layer is coated with the first pressure-sensitive adhesive layer and cured.

8. The method for preparing the electronic screen protective film according to claim 7, characterized in that: The temperature of the thermal curing is 110-155°C, and the energy of the UV curing is 1000-2000mJ / cm 2 ; And / or, the coating is performed by blade coating or slit coating in all steps.

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