Fluorine release coating, fluorine release film and application thereof

Abstract

The invention provides a fluorine release coating, a fluorine release film and application of the fluorine release coating and the fluorine release film. The fluorine release coating comprises the following components in percentage by weight: 40-50 parts of a fluorine release agent (A), 25-45 parts of vinyl-terminated fluorosilicone oil (B), 0.1-1 part of side chain vinyl fluorosilicone oil (C), 2.45-2.85 parts of a curing agent (D), 0.01-0.5 part of a functional aid (E), 0.01-0.1 part of a catalyst (F) and 93-96% of a diluent (G), and the total weight of the components (A), (B), (C), (D), (E), (F) and (G) is 100%. The release coating disclosed by the invention is high in adaptability with an organic silicon OCA (Optical Clear Adhesive) layer, ultralow release force and high residual adhesion rate are kept for a long time, and the phenomena of film tearing, adhesive pulling and reverse release are avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of coating compositions, and in particular to a fluorine release coating, a fluorine release film and applications thereof. Background Art

[0002] PET fluorine release film, also known as fluorine film, refers to a functional film that is coated with fluorine release coating on the surface of PET base film. As a release film for the light release surface of silicone OCA, fluorine film is easier to achieve the effect of ultra-light peeling.

[0003] However, the current fluorochemical release coatings still have compatibility issues between release agents and different types of silicone OCAs. The incompatibility between the two can cause silicone OCAs to release in the application end, tear off the film and pull the glue, and the release force will increase significantly during storage, and there may even be serious consequences such as the fluorochemical film and silicone OCA sticking to each other, which greatly affects the yield of the silicone OCA product itself.

[0004] Therefore, how to improve the compatibility of release agent and silicone OCA has become a problem that needs to be solved urgently. Summary of the invention

[0005] In order to solve the above technical problems, the present invention designs a fluorine release coating. A functional additive is added to the formula to adjust the release force and adhesion of the release film at the same time, and the film material is prevented from producing common paint film defects such as rainbow lines and cross-sectional lines by adjusting the diluent. The formula has good adaptability to a variety of OCAs, can provide long-term stable low release force, and significantly reduce the anti-release, film tearing and adhesive pulling problems of organic silicon OCA during the lamination process, and the fluorine film has no obvious effect on the peeling force of the organic silicon OCA itself.

[0006] In a first aspect, the present invention provides a fluorine-based release coating, wherein the fluorine-based release coating comprises the following components in percentage by weight:

[0007] The fluorine release agent (A) is 40-50 parts, for example, it can be 41 parts, 42 parts, 43 parts, 44 parts, 45 parts, 46 parts, 47 parts, 48 ​​parts, 49 parts and specific values ​​between the above points.

[0008] The vinyl-terminated fluorosilicone oil (B) is 25-45 parts, for example, 28 parts, 31 parts, 34 parts, 37 parts, 40 parts, 43 parts and specific values ​​between the above values.

[0009] The side chain vinyl fluorosilicone oil (C) is 0.1-1 part, for example, it can be 0.2 part, 0.3 part, 0.4 part, 0.5 part, 0.6 part, 0.7 part, 0.8 part, 0.9 part and specific values ​​between the above points.

[0010] The curing agent (D) is 2.45-2.85 parts, for example, it can be 2.5 parts, 2.55 parts, 2.6 parts, 2.65 parts, 2.7 parts, 2.75 parts, 2.8 parts and specific values ​​between the above points.

[0011] The functional additive (E) is 0.01-0.5 parts, for example, it can be 0.05 parts, 0.1 parts, 0.15 parts, 0.2 parts, 0.25 parts, 0.3 parts, 0.35 parts, 0.4 parts, 0.45 parts and specific values ​​between the above points.

[0012] The catalyst (F) is 0.01-0.1 parts, for example, it can be 0.02 parts, 0.03 parts, 0.04 parts, 0.05 parts, 0.06 parts, 0.07 parts, 0.08 parts, 0.09 parts and specific values ​​between the above points.

[0013] The fluorine release coating also includes a diluent (G). Based on the total weight of components (A), (B), (C), (D), (E), (F), and (G) as 100%, the amount of the diluent (G) is 93%-96%, for example, it can be 93.5%, 94%, 94.5%, 95%, 95.5% and specific values ​​between the above points.

[0014] The fluorine release agent component in the release coating formula developed by the present invention ensures that the organosilicon OCA product can provide a stable and low release force during long-term storage.

[0015] The curing agent added in the present invention needs to be within the range of 2.45-2.85 parts to effectively solve the problem of having a high residual bonding rate and a low release force. Too little curing agent will lead to poor curing of the release coating, significantly reduce the residual bonding rate, pollute the surface of the organic silicon OCA colloid, and reduce its bonding performance to the substrate; too much curing agent will cause the cross-linking network of the release coating to be too dense, which is not conducive to the migration of fluorine and significantly increases the release force.

[0016] The release coating of the present invention has strong compatibility with the organic silicon OCA optical adhesive layer, maintains ultra-low release force and high residual bonding rate for a long time, and does not cause film tearing, adhesive pulling and reverse release.

[0017] Preferably, the vinyl-terminated fluorosilicone oil has the following structure:

[0018]

[0019] Wherein n and x are independently integers greater than or equal to 1, for example, 2, 3, 4, 5, 6, etc.

[0020] Preferably, the vinyl-terminated fluorosilicone oil comprises a combination of high-viscosity vinyl-terminated fluorosilicone oil, medium-viscosity vinyl-terminated fluorosilicone oil and low-viscosity vinyl-terminated fluorosilicone oil.

[0021] Vinyl fluorosilicone oils of different viscosities are used in combination to ensure good leveling while providing sufficient cohesive strength for the release coating, ensuring that the release coating has good scratch resistance and a high residual adhesion rate.

[0022] Preferably, the high viscosity vinyl-terminated fluorosilicone oil has a viscosity of 10000-14000 mPa·s at 25°C, for example, 10500 mPa·s, 11000 mPa·s, 11500 mPa·s, 12000 mPa·s, 12500 mPa·s, 13000 mPa·s, 13500 mPa·s and specific values ​​between the above values.

[0023] The medium-viscosity vinyl-terminated fluorosilicone oil has a viscosity of 5000-10000 mPa·s at 25° C., for example, it may be 5500 mPa·s, 6000 mPa·s, 6500 mPa·s, 7000 mPa·s, 7500 mPa·s, 8000 mPa·s, 8500 mPa·s, 9000 mPa·s, 9500 mPa·s and specific values ​​between the above points.

[0024] The viscosity of the low-viscosity vinyl-terminated fluorosilicone oil at 25° C. is 1000-5000 mPa·s, for example, 1500 mPa·s, 2000 mPa·s, 2500 mPa·s, 3000 mPa·s, 3500 mPa·s, 4000 mPa·s, 4500 mPa·s and specific values ​​between the above values.

[0025] Preferably, the mass ratio of the high viscosity vinyl-terminated fluorosilicone oil, the medium viscosity vinyl-terminated fluorosilicone oil, and the low viscosity vinyl-terminated fluorosilicone oil is 1:(0.5-2):(0.6-1.75). 0.5-2 can be, for example, 0.7, 0.9, 1.1, 1.3, 1.5, 1.7, 1.9, and specific values ​​between the above values; 0.6-1.75 can be, for example, 0.8, 1, 1.2, 1.4, 1.6, and specific values ​​between the above values.

[0026] Preferably, the side chain vinyl fluorosilicone oil has the following structure:

[0027]

[0028] Wherein y and z are independently integers greater than or equal to 1, such as 2, 3, 4, 5, 6, etc.;

[0029] The viscosity of the side chain vinyl fluorosilicone oil at 25° C. is 14000-17000 mPa·s, for example, 14500 mPa·s, 15000 mPa·s, 15500 mPa·s, 16000 mPa·s, 16500 mPa·s and specific values ​​between the above values.

[0030] Preferably, the curing agent is methyl hydrogen-containing fluorosilicone oil.

[0031] Preferably, the curing agent has the following structure:

[0032]

[0033] Wherein a, b, and c are independently integers greater than or equal to 1, such as 2, 3, 4, 5, 6, etc.

[0034] Preferably, the functional additive has the following structure:

[0035]

[0036] Wherein d1 is an integer of 1-1000, for example, 100, 200, 300, 400, 500, 600, 700, 800, 900, etc.; d2 is an integer of 1-1000, for example, 100, 200, 300, 400, 500, 600, 700, 800, 900, etc.

[0037] The functional additive used in the present invention contains an alkoxy group at the end, and the alkoxy group forms a hydrogen bond with the polar group on the surface of the substrate, or hydrolyzes and condenses with the hydroxyl group on the surface of the substrate, thereby anchoring on the surface of the substrate. At the same time, the functional additive contains a large number of fluorine-containing groups. When heated and baked, it quickly migrates to the surface away from the substrate under the promotion of the fluorine-containing compound diluent. After curing, the fluorine-containing groups are enriched on the surface, the surface energy is reduced, and the release force is reduced. The addition of the functional additive in the present invention can effectively solve the problem of high adhesion and low film tearing force being difficult to take into account, enhance the bonding force between the release coating and the substrate, improve the adhesion and residual bonding rate, and reduce the release force of the release film.

[0038] The functional additive used in the present invention is within the range of 0.01-0.5 parts, which can effectively solve the problem of high adhesion (high residual bonding rate) and low release force. If the functional additive is too little, the fluorine content on the surface of the release coating decreases, resulting in an increase in the release force; if the functional additive is too much, the cohesive strength of the release coating is reduced, silicon transfer is likely to occur, resulting in a decrease in the residual bonding rate.

[0039] The functional additive of the present invention has a single-end alkoxy structure, which can achieve low release force and excellent silicone OCA lamination application performance. Due to the difficulty of chain segment movement and limited migration of fluorine groups, the release force of the dual-end alkoxy-terminated functional additive is significantly increased, and film tearing, glue pulling and reverse release phenomena will occur in silicone OCA applications. Functional additives without anchoring groups have low adhesion between the substrate and the release coating.

[0040] Preferably, the preparation method of the functional additive comprises the following steps:

[0041] S1, mixing a fluorinated siloxane monomer and a pentamethyldisiloxane end-capping agent to react to obtain a hydrogen-terminated methyl fluorinated polysiloxane;

[0042] S2, mixing the hydrogen-terminated methyl fluorine-containing polysiloxane obtained in step S1 with the vinyl siloxane, and reacting them to obtain the functional auxiliary agent.

[0043] Preferably, the pentamethyldisiloxane end-capping agent accounts for 0.2-0.25% of the total mass of the fluorinated siloxane monomer, for example, it may be 0.21%, 0.22%, 0.23%, 0.24% and specific values ​​between the above values.

[0044] Preferably, the fluorine-containing siloxane monomer includes 2,4,6,8-tetramethyl-2,4,6,8-tetrakis(3,3,3-trifluoropropyl)cyclotetrasiloxane and / or 1,3,5-trimethyl-1,3,5-tris(3,3,3-trifluoropropyl)cyclotrisiloxane.

[0045] Preferably, the vinyl siloxane includes at least one of vinyl trimethoxy siloxane, vinyl triethoxy siloxane, vinyl methyl dimethoxy silane, γ-methacryloxypropyl trimethoxy silane, γ-methacryloxypropyl triethoxy silane, and γ-methacryloxypropyl dimethoxymethyl silane.

[0046] Preferably, the molar ratio of the vinyl siloxane to pentamethyldisiloxane is (3-5):1, for example, 3.25:1, 3.5:1, 3.75:1, 4:1, 4.25:1, 4.5:1, 4.75:1 and specific values ​​between the above values.

[0047] Preferably, the reaction in step S1 is carried out in the presence of a catalyst.

[0048] Preferably, the catalyst for the reaction in step S1 includes any one of trifluoromethanesulfonic acid, hydrochloric acid, sulfuric acid, and p-toluenesulfonic acid, or a combination of at least two thereof.

[0049] Preferably, the reaction temperature in step S1 is 75-95°C, for example, it can be 76°C, 77°C, 78°C, 79°C, 80°C, 81°C, 82°C, 83°C, 84°C, 86°, 88°C, 90°C, 92°C, 94°C and specific values ​​between the above points; the reaction time is 10-13h, for example, it can be 10.5h, 11h, 11.5h, 12h, 12.5h and specific values ​​between the above points.

[0050] Preferably, the reaction in step S2 is carried out in the presence of a catalyst.

[0051] Preferably, the catalyst for the reaction in step S2 comprises a Karstedt platinum catalyst and / or a Speier catalyst.

[0052] Preferably, the reaction temperature in step S2 is 80-90°C, for example, it can be 81°C, 82°C, 83°C, 84°C, 85°C, 86°C, 87°C, 88°C, 89°C and specific values ​​between the above points; the reaction time is 16-24h, for example, it can be 17h, 18h, 19h, 20h, 21h, 22h, 23h and specific values ​​between the above points.

[0053] Preferably, the catalyst is selected from zero-valent platinum complexes.

[0054] Preferably, the diluent comprises an alkane compound and a fluorine-containing compound.

[0055] When adding fluorine-containing compounds to the diluent and heating and baking, the volatilization of the fluorine-containing compounds can effectively promote the migration of fluorine-containing groups in terminal vinyl fluorosilicone oil, side vinyl fluorosilicone oil, and functional additives to the surface away from the substrate, thereby obtaining a release film with ultra-low release force. If there is no fluorine-containing compound in the diluent, the fluorine groups enriched on the surface will be reduced, the release force will be improved, and rainbow lines and cross-sectional lines will be easily formed. When used for silicone OCA bonding, the film will be torn off and the adhesive will be pulled, and the release will be reversed.

[0056] Preferably, the alkane compound includes at least one of n-heptane, methyl isobutyl ketone, butyronitrile, 1,4-dioxane, pyridine, butanol, octane or butyl acetate.

[0057] Preferably, the fluorine-containing compound includes at least one of benzyltrifluoromethane, decafluoro-3-methoxy-2-trifluoromethylpentane or 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether.

[0058] Preferably, the mass ratio of the alkane compound to the fluorine-containing compound is 3-5:1, for example, it can be 3.3:1, 3.6:1, 3.9:1, 4.2:1, 4.5:1, 4.8:1 and specific values ​​between the above points.

[0059] Preferably, the diluent includes a combination of a diluent having a boiling point of 50-89° C., a diluent having a boiling point of 90-109° C., and a diluent having a boiling point of 110-130° C. 50-89° C. may be, for example, 55° C., 60° C., 65° C., 70° C., 75° C., 80° C., 85° C., and specific values ​​between the above values; 90-109° C. may be, for example, 93° C., 96° C., 99° C., 102° C., 105° C., 108° C., and specific values ​​between the above values; 110-130° C. may be, for example, 113° C., 116° C., 119° C., 122° C., 125° C., 128° C., and specific values ​​between the above values.

[0060] Adjusting the boiling point gradient of the diluent is beneficial to promoting coating leveling, fluorine group migration and improving curing efficiency.

[0061] Preferably, the diluent having a boiling point of 50-89° C. includes 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether;

[0062] Preferably, the diluent having a boiling point of 90-109° C. includes any one of n-heptane, 1,4-dioxane, benzenetrifluoromethane, decafluoro-3-methoxy-2-trifluoromethylpentane, or a combination of at least two thereof;

[0063] Preferably, the diluent with a boiling point of 110-130° C. includes any one of methyl isobutyl ketone, butyronitrile, pyridine, butanol, octane, and butyl acetate, or a combination of at least two thereof;

[0064] Preferably, the viscosity of the fluorine release coating at 25° C. is 10-50 MPa·s, for example, it may be 15 MPa·s, 20 MPa·s, 25 MPa·s, 30 MPa·s, 35 MPa·s, 40 MPa·s, 45 MPa·s, and specific values ​​between the above values.

[0065] In a second aspect, the present invention provides a fluorine release film, comprising a substrate layer and a release coating layer attached to the surface of the substrate, wherein the release coating layer is obtained by curing the fluorine release coating described in the first aspect.

[0066] Preferably, the material of the substrate layer is PET film.

[0067] Biaxially stretched PET film is preferred.

[0068] Preferably, the corona value of the substrate is ≥52, for example, it may be 53, 54, 55, 56, 57, etc.

[0069] Preferably, the thickness of the release coating layer is 0.4-0.5 μm, for example, it may be 0.41 μm, 0.42 μm, 0.43 μm, 0.44 μm, 0.45 μm, 0.46 μm, 0.47 μm, 0.48 μm, 0.49 μm and specific values ​​between the above values.

[0070] Preferably, the curing temperature is 130-160°C, for example, it can be 135°C, 140°C, 145°C, 150°C, 155°C and specific values ​​between the above points; the curing time is 1-5min, for example, it can be 1.5min, 2min, 2.5min, 3min, 3.5min, 4min, 4.5min and specific values ​​between the above points.

[0071] In a third aspect, the present invention provides an organosilicon OCA adhesive, which includes a light release film, an optical adhesive layer, and a heavy release film, wherein the optical adhesive layer is located between the light release film and the heavy release film, and the light release film is the fluorine release film described in the second aspect.

[0072] In a fourth aspect, the present invention provides an application of the fluorine release coating described in the first aspect, the fluorine release film described in the second aspect, or the silicone OCA adhesive described in the third aspect in display bonding.

[0073] Compared with the prior art, the present invention has at least the following beneficial effects:

[0074] The fluorine release agent component in the release coating formula developed by the present invention ensures that the organosilicon OCA product can provide a stable and low release force during long-term storage.

[0075] The curing agent has a great influence on the release force. When the curing agent is added in too low a proportion, the release coating will not cure well, contaminating the surface of the silicone OCA colloid and reducing its adhesion to the substrate. As the curing agent proportion increases, although the adhesion of the release coating to the substrate is improved, excessive curing agent will make the cross-linked network of the release coating too dense, which is not conducive to the migration of fluorine-containing groups to the coating surface during the drying process, resulting in increased release force.

[0076] The release coating of the present invention has strong compatibility with the organic silicon OCA optical adhesive layer, maintains ultra-low release force and high residual bonding rate for a long time, and does not cause film tearing, adhesive pulling and reverse release. DETAILED DESCRIPTION

[0077] For the convenience of understanding the present invention, the present invention lists the following embodiments. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0078] The sources of the raw materials used in the embodiments of the present invention are as follows:

[0079] Table 1 Fluorine release agent

[0080] Code Manufacturer Brand Solid Viscosity (mPa·s) A-1 Dow Corning <![CDATA[SYL-OFF TM 7795]]> 80％ 5,000

[0081] Table 2 Vinyl-terminated fluorosilicone oil

[0082]

[0083] Table 3 Vinyl Fluorosilicone Oil

[0084]

[0085] Table 4 Curing agent

[0086]

[0087] Table 5 Catalyst

[0088] Code supplier Brand Viscosity (mPa·s) F-1 Dow Corning <![CDATA[SYL-OFF TM 4000 Catalyst]]> 46

[0089] Table 6 Diluent

[0090]

[0091] Table 7 Test tape

[0092]

[0093] The test standards of the present invention are as follows:

[0094] Table 8 Test Standards

[0095]

[0096]

[0097] Test methods for silicone OCA lamination applications:

[0098] The light release film of the silicone OCA product was replaced with the release film prepared in the present invention, and then it was torn open by hand after being stored at room temperature for 6 months to check whether there was film tearing and glue pulling, and reverse release.

[0099] Preparation Example 1

[0100] Preparation of diluent G1: Add 50 parts by weight of n-heptane, 45 parts by weight of methyl isobutyl ketone, 6 parts by weight of benzenetrifluoromethane, 10 parts by weight of decafluoro-3-methoxy-2-trifluoromethylpentane, and 8 parts by weight of 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether into a fluorination barrel in proportion and stir for 5 minutes to obtain diluent G1.

[0101] Preparation Example 2

[0102] Preparation of diluent G2: Add 62 parts by weight of n-heptane and 57 parts by weight of methyl isobutyl ketone into a fluorination barrel according to proportion and stir for 5 minutes to obtain diluent G2.

[0103] Preparation Example 3

[0104] Preparation of diluent G3: Add 50 parts by weight of n-heptane and 10 parts by weight of decafluoro-3-methoxy-2-trifluoromethylpentane into a fluorination barrel according to proportion and stir for 5 minutes to obtain diluent G3.

[0105] Preparation Example 4

[0106] Preparation of functional additive E1: 21.5 g D4 F (2,4,6,8-tetramethyl-2,4,6,8-tetrakis(3,3,3-trifluoropropyl)cyclotetrasiloxane), 50.2 g D3 F (1,3,5-trimethyl-1,3,5-tri(3,3,3-trifluoropropyl)cyclotrisiloxane), 0.15g1,1,1,3,3-pentamethyldisiloxane were put into a 250mL dry three-necked flask, then placed in an oil bath and equipped with a condenser, heated to 90°C under a nitrogen atmosphere, magnetically stirred and mixed for 30 minutes, and then added with a reaction catalyst CF3SO3H (trifluoromethanesulfonic acid) accounting for 8% of the mass fraction of the fluorinated siloxane monomer, and the reaction was continued for 12 hours. After the reaction was completed, it was filtered and the small molecules were removed under reduced pressure for 2 hours to obtain a single-end hydrogen methyl fluorinated polysiloxane. Then the above product was added to a dry three-necked flask, 0.6g of vinyl trimethoxysiloxane was added, and Karstedt platinum catalyst (the concentration of the catalyst in the reaction system was 85mg / L) was added, and the reaction was carried out at 85°C for 18 hours. After the reaction was completed, it was distilled to obtain the functional additive E1, and the fluorine content was 32% as tested by XPS.

[0107] The structure of functional additive E1 is shown below.

[0108]

[0109] Preparation Example 5

[0110] Preparation of functional additive E2: 21.5 g D4 F (2,4,6,8-tetramethyl-2,4,6,8-tetrakis(3,3,3-trifluoropropyl)cyclotetrasiloxane), 50.2 g D3 F(1,3,5-trimethyl-1,3,5-tri(3,3,3-trifluoropropyl)cyclotrisiloxane), 0.15g1,1,3,3-tetramethyldisiloxane were put into a 250mL dry three-necked flask, then placed in an oil bath and equipped with a condenser, heated to 90°C under a nitrogen atmosphere, magnetically stirred and mixed for 30 minutes, and then a reaction catalyst CF3SO3H accounting for 8% of the mass fraction of the fluorinated siloxane monomer was added, and the reaction was continued for 12 hours. After the reaction was completed, it was filtered and the small molecules were removed by decompression for 2 hours to obtain a terminal hydrogen methyl fluorinated polysiloxane. Then the above product was added to a dry three-necked flask, 0.13g of vinyl trimethoxysiloxane was added, and Karstedt platinum catalyst (the concentration of the catalyst in the reaction system was 85mg / L) was added, and the reaction was carried out at 85°C for 18 hours. After the reaction was completed, the functional additive E2 was obtained by distillation. The fluorine content was 32% as tested by XPS. The structure of functional additive E2 is shown below.

[0111]

[0112] Examples 1-7, Comparative Examples 1-9

[0113] (1) adding a fluorine release agent, vinyl-terminated fluorosilicone oil, side vinyl-terminated fluorosilicone oil, and a functional additive to a diluent in proportion, and stirring for 10 minutes to obtain a mixed solution 1;

[0114] (2) adding the curing agent into the mixed solution 1 according to the proportion, stirring for 5 minutes, and obtaining the mixed solution 2;

[0115] (3) Add the catalyst into the mixed solution 2 in proportion and stir for 5 minutes to obtain a fluorine release coating with a corresponding solid content.

[0116] (4) Preparation of release film: The prepared fluorine release coating was coated onto a biaxially oriented polyester film with a corona surface by a wire rod, and baked at 150° C. for 1-2 min to obtain a release film.

[0117] The fluorine-based release coatings provided in Examples 1-7 and Comparative Examples 1-9 of the present invention have formulations as shown in Tables 9 and 10:

[0118] Table 9 Example formulation composition

[0119]

[0120]

[0121] Table 10 Comparative Example Formula Composition

[0122]

[0123]

[0124] The release films prepared in the above examples and comparative examples were comprehensively evaluated in terms of appearance, release force, residual adhesion rate, and silicone OCA lamination application. The specific results are shown in Tables 11 and 12:

[0125] Table 11 Example performance

[0126]

[0127] Table 12 Comparative Example Performance

[0128]

[0129] It can be seen from Examples 1-7 that the fluorine-containing compound in the diluent of the present invention can promote the migration of the fluorine-containing groups in the end vinyl fluorosilicone oil and the side vinyl fluorosilicone oil to the surface away from the substrate during the coating process, and the fluorine-containing groups are enriched on the surface after curing, thereby reducing the release force between the release layer and the adhesive layer; and the functional additives of Examples 1-7 contain a methoxy anchoring group at one end and a large number of fluorine groups in the chain; the methoxy group can form a hydrogen bond with the polar group on the surface of the substrate (PET film) or hydrolyze and condense with the hydroxyl group, thereby anchoring on the surface of the substrate, and the fluorine group at the free end can migrate to the surface of the release layer, while increasing the fluorine content of the release coating, and with other components, it can effectively solve the problem that it is difficult to have both high adhesion (high residual bonding rate) and low release force. The prepared release film has no rainbow lines and cross-sectional lines, and the release force is still maintained below 5gf / in after being placed at room temperature for 6 months, and the residual bonding rate is greater than 85%. It is applied to the silicone OCA adhesive layer without film tearing, glue pulling and reverse release.

[0130] It can be seen from Example 1 and Comparative Example 1 that the addition of functional additives in the present invention can reduce the release force and increase the residual bonding rate, while when no functional additive is added, the release force is increased and the residual bonding rate is reduced.

[0131] It can be seen from Example 1 and Comparative Examples 2 and 3 that the functional additives added in the present invention need to be within a certain range to effectively solve the problem of high adhesion and low release force. In Comparative Example 2, the amount of functional additives used is too small, which is not conducive to the surface migration of fluorine-containing segments, and the fluorine content on the surface of the release coating decreases, resulting in an increase in release force; in Comparative Example 3, the amount of functional additives used is too large, which reduces the cohesive strength of the release coating, and silicon transfer is prone to occur, resulting in a decrease in residual adhesion rate.

[0132] It can be seen from Example 1 and Comparative Examples 4 and 5 that the curing agent added in the present invention needs to be within a certain range to effectively solve the problem of having a high residual bonding rate and a low release force. In Comparative Example 4, the amount of curing agent used is too little, the release coating is not cured well, and the residual bonding rate is significantly reduced; in Comparative Example 5, the amount of curing agent used is too much, the cross-linking network of the release coating is too dense, which is not conducive to the migration of fluorine, and the release force is significantly increased.

[0133] It can be seen from Example 1 and Comparative Example 6 that the combination of the high-viscosity vinyl fluorosilicone oil, the medium-viscosity vinyl fluorosilicone oil and the low-viscosity fluorosilicone oil of the present invention is more conducive to regulating the modulus of the release layer colloid and improving the residual rate. However, in Comparative Example 6, no medium-viscosity vinyl fluorosilicone oil was added, and the residual bonding rate was reduced.

[0134] It can be seen from Example 1 and Comparative Example 7 that adjusting the boiling point gradient of the diluent of the present invention is beneficial to promoting coating leveling, fluorine group migration and improving curing efficiency. The boiling point of the diluent of Comparative Example 7 is within the range of 90-109°C, and the release force increases after being placed at room temperature for 6 months, and rainbow lines and cross-sectional lines appear on the appearance.

[0135] It can be seen from Example 1 and Comparative Example 8 that the functional additive of the present invention needs to have a specific structure to achieve low release force and excellent silicone OCA lamination application performance. Comparative Example 8 replaces functional additive E1 with functional additive E2. E2 contains anchor groups at both ends, which makes it difficult for the chain segments to move, restricts the migration of fluorine groups, increases the release force, and causes film tearing, adhesive pulling, and reverse release in silicone OCA applications.

[0136] It can be seen from Example 1 and Comparative Example 9 that the diluent of the present invention needs to include a fluorine-containing compound in order to achieve a release film with no rainbow lines or cross-sectional lines, low release force and excellent silicone OCA lamination application performance. Comparative Example 9 replaces diluent G1 with diluent G2. Diluent G2 does not contain a fluorine-containing compound, the fluorine groups enriched on the surface are reduced, the release force is improved, and rainbow lines and cross-sectional lines appear. When applied to silicone OCA lamination, film tearing, glue pulling, and reverse release phenomena occur.

[0137] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. A fluorine release coating, characterized in that: The fluorine release coating comprises the following components in percentage by weight: The fluorine release coating also includes a diluent (G). Based on the total weight of components (A), (B), (C), (D), (E), (F), and (G) being 100%, the weight of the diluent (G) accounts for 93%-96%.

2. The fluorine release coating according to claim 1, characterized in that: The vinyl-terminated fluorosilicone oil has the structure shown below: Wherein n and x are independently integers greater than or equal to 1; Preferably, the vinyl-terminated fluorosilicone oil comprises a combination of high-viscosity vinyl-terminated fluorosilicone oil, medium-viscosity vinyl-terminated fluorosilicone oil, and low-viscosity vinyl-terminated fluorosilicone oil; Preferably, the high viscosity vinyl-terminated fluorosilicone oil has a viscosity of 10000-14000 mPa·s at 25°C, the medium viscosity vinyl-terminated fluorosilicone oil has a viscosity of 5000-10000 mPa·s at 25°C, and the low viscosity vinyl-terminated fluorosilicone oil has a viscosity of 1000-5000 mPa·s at 25°C; Preferably, the mass ratio of the high viscosity vinyl-terminated fluorosilicone oil, the medium viscosity vinyl-terminated fluorosilicone oil, and the low viscosity vinyl-terminated fluorosilicone oil is 1:(0.5-2):(0.6-1.75).

3. The fluorine release coating according to claim 1 or 2, characterized in that: The side chain vinyl fluorosilicone oil has the following structure: Wherein y and z are independently integers greater than or equal to 1; The viscosity of the side chain vinyl fluorosilicone oil at 25° C. is 14000-17000 mPa·s.

4. The fluorine-based release coating according to any one of claims 1 to 3, characterized in that: The curing agent is methyl hydrogen-containing fluorosilicone oil; Preferably, the curing agent is a compound having the following structure: wherein a, b, and c are independently integers greater than or equal to 1.

5. The fluorine-based release coating according to any one of claims 1 to 4, characterized in that: The functional additive has the following structure: Wherein d1 is an integer from 1 to 1000, and d2 is an integer from 1 to 1000; Preferably, the preparation method of the functional additive comprises the following steps: S1, mixing a fluorinated siloxane monomer and a pentamethyldisiloxane end-capping agent to react to obtain a hydrogen-terminated methyl fluorinated polysiloxane; S2, mixing the hydrogen-terminated methyl fluorinated polysiloxane obtained in step S1 with vinyl siloxane, and reacting them to obtain the functional additive; Preferably, the pentamethyldisiloxane end-capping agent accounts for 0.2-0.25% of the total mass of the fluorinated siloxane monomer; Preferably, the fluorine-containing siloxane monomer includes 2,4,6,8-tetramethyl-2,4,6,8-tetrakis(3,3,3-trifluoropropyl)cyclotetrasiloxane and / or 1,3,5-trimethyl-1,3,5-tris(3,3,3-trifluoropropyl)cyclotrisiloxane; Preferably, the vinyl siloxane includes at least one of vinyl trimethoxysiloxane, vinyl triethoxysiloxane, vinyl methyl dimethoxysilane, γ-methacryloxypropyl trimethoxysilane, γ-methacryloxypropyl triethoxysilane, and γ-methacryloxypropyl dimethoxymethylsilane; Preferably, the molar ratio of the vinyl siloxane to pentamethyldisiloxane is (3-5):1; Preferably, the reaction in step S1 is carried out in the presence of a catalyst; Preferably, the catalyst for the reaction in step S1 includes any one of trifluoromethanesulfonic acid, hydrochloric acid, sulfuric acid, and p-toluenesulfonic acid, or a combination of at least two thereof; Preferably, the reaction temperature in step S1 is 75-95°C and the reaction time is 10-13h; Preferably, the reaction in step S2 is carried out in the presence of a catalyst; Preferably, the catalyst for the reaction in step S2 comprises a Karstedt platinum catalyst and / or a Speier catalyst; Preferably, the reaction temperature in step S2 is 80-90° C., and the reaction time is 16-24 h.

6. The fluorine-based release coating according to any one of claims 1 to 5, characterized in that: The catalyst is selected from zero-valent platinum complexes.

7. The fluorine-based release coating according to any one of claims 1 to 6, characterized in that: The diluent includes an alkane compound and a fluorine-containing compound; Preferably, the alkane compound includes at least one of n-heptane, methyl isobutyl ketone, butyronitrile, 1,4-dioxane, pyridine, butanol, octane or butyl acetate; Preferably, the fluorine-containing compound includes at least one of benzenetrifluoromethane, decafluoro-3-methoxy-2-trifluoromethylpentane or 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether; Preferably, the mass ratio of the alkane compound to the fluorine-containing compound is (3-5):1; Preferably, the diluent includes a combination of a diluent having a boiling point of 50-89°C, a diluent having a boiling point of 90-109°C, and a diluent having a boiling point of 110-130°C; Preferably, the diluent having a boiling point of 50-89° C. includes 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether; Preferably, the diluent having a boiling point of 90-109° C. includes any one of n-heptane, 1,4-dioxane, benzenetrifluoromethane, decafluoro-3-methoxy-2-trifluoromethylpentane, or a combination of at least two thereof; Preferably, the diluent with a boiling point of 110-130° C. includes any one of methyl isobutyl ketone, butyronitrile, pyridine, butanol, octane, and butyl acetate, or a combination of at least two thereof; Preferably, the viscosity of the fluorine release coating at 25° C. is 10-50 mpa·s.

8. A fluorine release film, characterized in that: The fluorine release film comprises a substrate layer and a release coating layer attached to the surface of the substrate, wherein the release coating layer is obtained by curing the fluorine release coating according to any one of claims 1 to 7; Preferably, the material of the substrate layer is a PET film, more preferably a biaxially stretched PET film; Preferably, the corona value of the substrate is ≥52; Preferably, the thickness of the release coating layer is 0.4-0.5 μm; Preferably, the curing temperature is 130-160° C. and the curing time is 1-5 min.

9. An organic silicon OCA adhesive, characterized in that: The organic silicone OCA adhesive comprises a light release film, an optical adhesive layer, and a heavy release film, wherein the optical adhesive layer is located between the light release film and the heavy release film, and the light release film is the fluorine release film as claimed in claim 8.

10. Use of the fluorine release coating according to any one of claims 1 to 7, the fluorine release film according to claim 8, or the silicone OCA adhesive according to claim 9 in display bonding.

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