Silicone release paper containing heat-sensitive coating

Abstract

The present invention relates to a silicone release paper containing a heat-sensitive coating, and belongs to the technical field of silicone release paper. A silicone release paper containing a heat-sensitive coating comprises a paper substrate, a heat-sensitive coating and a silicone release film layer, wherein the heat-sensitive coating is coated on the surface of the paper substrate, the silicone release film layer is coated on the surface of the heat-sensitive coating, and the silicone release film layer comprises the following raw materials: epoxy soybean oil-modified acrylate, hydroxy polydimethylsiloxane, modified hollow glass microspheres, solvent, catalyst, n-butyl acrylate and curing agent; the curing agent is composed of silane-modified ester and isocyanate; the present invention significantly improves the dispersibility and compatibility of the hollow glass microspheres in the organic system by epoxy-modifying the hollow glass microspheres, and combines the addition of hydroxy polydimethylsiloxane and silane-modified ester, and significantly improves the crosslinking density of the reaction system by combining the addition of isocyanate containing NCO group, so that the film layer has excellent wear resistance and adhesion.

Description

Technical Field

[0001] The invention belongs to the technical field of silicone release paper and relates to silicone release paper containing a heat-sensitive coating. Background Art

[0002] In the field of silicone release paper, silicone release agents are gaining widespread attention and application due to their unique properties. These release agents, with their low surface tension, high transparency, non-toxicity, high temperature resistance, and strong weather resistance, are widely used as antifouling and anti-adhesion coatings on a variety of substrates, including metals, ceramics, paper, plastics, and textiles.

[0003] Silicone release coatings work by applying a non-migrating, low-surface-energy coating to various substrates (such as release paper, glassine paper, masking tape, kraft paper, whiteboard, and coated paper). This coating not only imparts non-stick properties but also allows for adjustable viscosity, from slightly sticky to moderately sticky. This flexible application makes silicone release coatings promising in a wide range of applications.

[0004] However, despite the numerous advantages of silicone release agents, the cured coatings still exhibit some drawbacks in terms of physical properties and service life. These primarily manifest in low coating hardness, poor wear resistance, and susceptibility to aging, which limit their application in certain specialized environments and demanding applications. Therefore, modifying silicone release agents to improve their physical properties and service life has become a research hotspot.

[0005] One possible modification method is to introduce hollow glass microspheres as fillers. Hollow glass microspheres are smooth, micron-sized hollow glass microspheres primarily composed of borosilicate glass. These microspheres offer advantages such as low density, high hardness, excellent wear resistance, and high thermal stability, and therefore hold broad application prospects for enhancing material properties.

[0006] However, when hollow glass microspheres are added as fillers to a polymer matrix, compatibility issues arise due to the significant difference in polarity between the two. This means that the bonding between the hollow glass microspheres and the polymer matrix is ​​weak, which can easily lead to a decrease in coating performance. Summary of the Invention

[0007] The present invention aims to provide a silicone release paper containing a heat-sensitive coating. The present invention significantly improves the dispersibility and compatibility of the hollow glass microspheres in an organic system by epoxy-modifying the hollow glass microspheres and adding hydroxyl polydimethylsiloxane and silane-modified ester. In addition, the crosslinking density of the reaction system is significantly increased by adding silane-modified esters with multiple active functional groups, isocyanates with NCO groups, and hydroxyl polydimethylsiloxane to the system, thereby providing excellent wear resistance and adhesion.

[0008] The purpose of the present invention can be achieved through the following technical solutions:

[0009] A silicone release paper containing a heat-sensitive coating comprises a paper substrate, a heat-sensitive coating and a silicone release film layer, wherein the heat-sensitive coating is applied to the surface of the paper substrate, and the silicone release film layer is applied to the surface of the heat-sensitive coating. The silicone release film layer comprises the following raw materials in parts by weight:

[0010]

[0011] As a preferred technical solution of the present invention, the curing agent is prepared by mixing silane-modified ester and isocyanate in a mass ratio of 5-10:3-4.

[0012] As a preferred technical solution of the present invention, the preparation method of the modified hollow glass microspheres comprises the following steps:

[0013] S1, mixing the epoxy soybean oil with a catalyst, adding a silane coupling agent, heating and stirring, to obtain silane-modified epoxy soybean oil;

[0014] S2. Adding hollow glass microspheres to the silane-modified epoxy soybean oil, stirring and mixing, and then heating to react to obtain modified hollow glass microspheres.

[0015] As a preferred technical solution of the present invention, in step S1, the heating and stirring is at a temperature of 60-80° C. and stirring for 2-3 hours; the silane coupling agent is KH-580; and the catalyst is azobisisobutyronitrile.

[0016] As a preferred technical solution of the present invention, in step S2, the hollow glass microspheres are composed of three types of hollow glass microspheres with a diameter ratio of 5.0-6.5:8.5-10:15-18 and a weight ratio of 2:2.4-3.0:5.0-6.2; the heating reaction is at a temperature of 80-90°C and a reaction time of 3-4 hours.

[0017] As a preferred technical solution of the present invention, in the preparation method of the modified hollow glass microspheres, the mass ratio of the epoxy soybean oil, catalyst, silane coupling agent and hollow glass microspheres is 10-12:0.6-0.8:1.0-1.2:2.0-2.5; the present invention chemically modifies the epoxy soybean oil through a silane coupling agent, and then couples it with the hollow glass microspheres through silane bonds; in this process, epoxy groups and mercapto groups are effectively introduced into the hollow glass microspheres, thereby optimizing the inert properties of their surfaces; this optimization enables the surface-modified hollow glass microspheres to exhibit good dispersibility in organic systems; in addition, when the hollow glass microspheres play an anchoring role after curing, the mechanical properties of the silicone release film layer are significantly improved.

[0018] Furthermore, the compounding of the three hollow glass microspheres facilitates their dispersion in the coating while allowing them to be staggered in the coating. The smaller microspheres effectively fill the gaps between the larger microspheres, thereby increasing the density and surface smoothness of the silicone release film layer and significantly improving its wear resistance.

[0019] The present invention discloses a method for preparing the silane-modified ester, comprising the following steps:

[0020] S11, stirring and mixing 2-methoxy-4-vinylphenol, 3-mercapto-1-propanol, and a photoinitiator, and reacting them under ultraviolet light to obtain a modified polyol;

[0021] S12, mixing the modified polyol, the acid anhydride compound and the catalyst, performing a temperature-raising reaction, and then dropwise adding a silane coupling agent for 30-40 minutes, cooling and discharging the material to obtain a silane-modified ester.

[0022] As a preferred technical solution of the present invention, in step S11, the mass ratio of 2-methoxy-4-vinylphenol, 3-mercapto-1-propanol and photoinitiator is 16-17:8.5-9.0:0.6-0.7; the photoinitiator is benzoin dimethyl ether; and the reaction time is 5-7 hours;

[0023] As a preferred technical solution of the present invention, in step S12, the silane coupling agent is silane coupling agent A174; the temperature increase reaction is carried out at a temperature of 80-90°C and the reaction time is 2-3h; the mass ratio of the modified polyol, methacrylic anhydride and catalyst is 10:16-18:0.2-0.3; the acid anhydride compound is one or two of maleic anhydride and itaconic anhydride; and the catalyst is 4-dimethylaminopyridine. The present invention uses the acid anhydride compound to perform monoesterification modification on the modified polyol, thereby introducing phenolic hydroxyl groups and active double bonds on the modified ester and generating carboxyl groups, thereby forming a prepolymer containing multiple active functional groups. The active double bonds in the prepolymer can form linear or three-dimensional polymer materials through self-polymerization or copolymerization, and other functional groups can also undergo polymerization reaction to form an interpenetrating network polymer, thereby improving the crosslinking density of the reaction system.

[0024] In the present invention, the added silane-modified ester has a highly reactive silane functional group, and there are sulfur atoms and methoxy groups in the molecular structure. Combined with the hydroxyl groups in the hydroxyl polydimethylsiloxane, it produces a physical and chemical adsorption effect with the modified hollow glass microspheres, synergistically enhancing the compatibility between the hollow glass microspheres and the organic system; 2-methoxy-4-vinylphenol contains a methoxy group and a rigid benzene ring, which can effectively improve the mechanical properties of the silicone release film layer while improving the compatibility with the hollow glass microspheres; in addition, the present invention improves the adhesion to the paper substrate by introducing a large number of oxygen-containing groups.

[0025] The invention discloses a preparation method of the organic silicon release film layer, comprising the following steps: stirring and mixing epoxy soybean oil-modified acrylate, hydroxy polydimethylsiloxane, modified hollow glass microspheres, a solvent, a catalyst and n-butyl acrylate, heating to 50-60° C., reacting for 20-30 minutes, cooling to room temperature, adding a curing agent and fully mixing to obtain the organic silicon release film layer; the solvent is ethyl acetate; and the catalyst is triphenylphosphine.

[0026] The invention discloses a preparation method of epoxy soybean oil modified acrylate. The preparation method is a prior art. The invention provides, but is not limited to, a preparation method comprising the following steps: preheating epoxy soybean oil and hydroquinone, adding acrylic acid and a catalyst, stirring for reaction, heating for reaction, and cooling to obtain epoxy soybean oil modified acrylate.

[0027] As a preferred technical solution of the present invention, in the preparation method of the epoxy soybean oil-modified acrylate, the preheating is heating to 70-80°C; the stirring reaction is carried out at a temperature of 80-95°C and a speed of 500-600 r / min for 30-45 minutes; the temperature increase reaction is carried out at 110-130°C for 1-3 hours; and the cooling is carried out to 80°C. The epoxy soybean oil may also be epoxy castor oil; the mass ratio of acrylic acid, epoxy vegetable oil, hydroquinone, and catalyst is 6-10:85-90:0.03-0.06:0.1-0.2; and the catalyst is one or more of triphenylphosphine, phosphoric acid, and triethylamine.

[0028] As a preferred technical solution of the present invention, the preparation of a silicone release paper containing a heat-sensitive coating includes coating a heat-sensitive coating on the surface of the paper, forming a heat-sensitive coating after curing, and coating a silicone release agent on the surface of the heat-sensitive coating. After curing, the silicone release paper containing the heat-sensitive coating is obtained. The release agent can be cured at a low temperature without affecting the subsequent printing of the heat-sensitive coating.

[0029] Beneficial effects of the present invention:

[0030] The present invention significantly improves the dispersibility and compatibility of the hollow glass microspheres in an organic system by epoxy-modifying the hollow glass microspheres and adding hydroxy polydimethylsiloxane and silane-modified ester. In addition, the cross-linking density of the reaction system is significantly increased by adding silane-modified esters with multiple active functional groups, isocyanates with NCO groups, and hydroxy polydimethylsiloxane to the system, thereby providing the system with excellent wear resistance and adhesion. DETAILED DESCRIPTION

[0031] In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, the specific implementation methods, structures, features and effects of the present invention are described in detail below in combination with the embodiments.

[0032] The preparation method of the epoxy soybean oil-modified acrylate comprises the following steps: preheating epoxy soybean oil and hydroquinone at 75°C, adding acrylic acid and a catalyst, stirring and reacting at 80°C, 500 rpm, and 40 minutes, then heating to 120°C and reacting for 2 hours, and cooling to obtain the epoxy soybean oil-modified acrylate; the mass ratio of the acrylic acid, epoxy soybean oil, hydroquinone, and catalyst is 8:85:0.03:0.1; and the catalyst is triphenylphosphine;

[0033] Example 1

[0034] A silicone release paper containing a heat-sensitive coating comprises a paper substrate, a heat-sensitive coating and a silicone release film layer, wherein the heat-sensitive coating is applied to the surface of the paper substrate, and the silicone release film layer is applied to the surface of the heat-sensitive coating. The silicone release film layer comprises the following raw materials in parts by weight:

[0035]

[0036] The curing agent is prepared by mixing silane-modified ester and isocyanate in a mass ratio of 5:3.

[0037] The preparation method of the modified hollow glass microspheres comprises the following steps:

[0038] S1. After mixing the epoxy soybean oil and the catalyst, a silane coupling agent is added, and the mixture is heated and stirred to obtain silane-modified epoxy soybean oil; wherein the heating and stirring is at a temperature of 60° C. and stirred for 2 hours; the silane coupling agent is KH-580; and the catalyst is azobisisobutyronitrile;

[0039] S2. Add hollow glass microspheres to silane-modified epoxy soybean oil, stir and mix, and then heat to react to obtain modified hollow glass microspheres; wherein the hollow glass microspheres are composed of three types of hollow glass microspheres with a diameter ratio of 5.0:8.5:15 and a weight ratio of 2:2.4:5.0; the heating reaction is carried out at a temperature of 80°C and a reaction time of 3 hours.

[0040] In the preparation method of the modified hollow glass microspheres, the mass ratio of the epoxidized soybean oil, the catalyst, the silane coupling agent and the hollow glass microspheres is 10:0.6:1.0:2.0.

[0041] The preparation method of the silane-modified ester comprises the following steps:

[0042] S11, stirring and mixing 2-methoxy-4-vinylphenol, 3-mercapto-1-propanol, and a photoinitiator, and reacting them under ultraviolet light to obtain a modified polyol; wherein the mass ratio of the 2-methoxy-4-vinylphenol, 3-mercapto-1-propanol, and the photoinitiator is 16:8.5:0.6; the photoinitiator is benzoin dimethyl ether; and the reaction time is 5 hours;

[0043] S12. The modified polyol, the acid anhydride compound and the catalyst are mixed, and after the temperature reaction is carried out, a silane coupling agent is added dropwise for 30 minutes, and the material is cooled and discharged to obtain a silane-modified ester; wherein the silane coupling agent is silane coupling agent A174; the temperature reaction is carried out at a temperature of 80°C for 2 hours; the mass ratio of the modified polyol, methacrylic anhydride and the catalyst is 10:16:0.2; the acid anhydride compound is maleic anhydride; and the catalyst is 4-dimethylaminopyridine.

[0044] The preparation method of the silicone release film layer comprises the following steps: stirring and mixing epoxy soybean oil-modified acrylate, hydroxy polydimethylsiloxane, modified hollow glass microspheres, a solvent, a catalyst and n-butyl acrylate, heating to 50° C., reacting for 20 minutes, cooling to room temperature, adding a curing agent and fully mixing to obtain the silicone release film layer; the solvent is ethyl acetate; and the catalyst is triphenylphosphine.

[0045] Example 2

[0046] A silicone release paper containing a heat-sensitive coating comprises a paper substrate, a heat-sensitive coating and a silicone release film layer, wherein the heat-sensitive coating is applied to the surface of the paper substrate, and the silicone release film layer is applied to the surface of the heat-sensitive coating. The silicone release film layer comprises the following raw materials in parts by weight:

[0047]

[0048]

[0049] The curing agent is prepared by mixing silane-modified ester and isocyanate in a mass ratio of 7:3.3.

[0050] The preparation method of the modified hollow glass microspheres comprises the following steps:

[0051] S1. After mixing the epoxy soybean oil and the catalyst, a silane coupling agent is added, and the mixture is heated and stirred to obtain silane-modified epoxy soybean oil; wherein the heating and stirring is at a temperature of 67° C. and stirring for 2.3 hours; the silane coupling agent is KH-580; and the catalyst is azobisisobutyronitrile;

[0052] S2. Add hollow glass microspheres to silane-modified epoxy soybean oil, stir and mix, and then heat to react to obtain modified hollow glass microspheres; wherein the hollow glass microspheres are composed of three types of hollow glass microspheres with a diameter ratio of 5.5:9:16 and a weight ratio of 2:2.6:5.4; the heating reaction is carried out at a temperature of 83°C and a reaction time of 3.3 hours.

[0053] In the preparation method of the modified hollow glass microspheres, the mass ratio of the epoxidized soybean oil, the catalyst, the silane coupling agent and the hollow glass microspheres is 10.7:0.67:1.07:2.2.

[0054] The preparation method of the silane-modified ester comprises the following steps:

[0055] S11, stirring and mixing 2-methoxy-4-vinylphenol, 3-mercapto-1-propanol, and a photoinitiator, and reacting them under ultraviolet light to obtain a modified polyol; wherein the mass ratio of the 2-methoxy-4-vinylphenol, 3-mercapto-1-propanol, and the photoinitiator is 16.3:8.7:0.63; the photoinitiator is benzoin dimethyl ether; and the reaction time is 5.7 hours;

[0056] S12. The modified polyol, the acid anhydride compound and the catalyst are mixed, and after the temperature reaction is carried out, a silane coupling agent is added dropwise for 33 minutes, and the material is cooled and discharged to obtain a silane-modified ester; wherein the silane coupling agent is silane coupling agent A174; the temperature reaction is carried out at a temperature of 83°C for 2.3 hours; the mass ratio of the modified polyol, methacrylic anhydride and the catalyst is 10:16.7:0.23; the acid anhydride compound is maleic anhydride; and the catalyst is 4-dimethylaminopyridine.

[0057] The preparation method of the silicone release film layer includes the following steps: stirring and mixing epoxy soybean oil-modified acrylate, hydroxy polydimethylsiloxane, modified hollow glass microspheres, a solvent, a catalyst and n-butyl acrylate, heating to 53° C., reacting for 23 minutes, cooling to room temperature, adding a curing agent and fully mixing to obtain the silicone release film layer; the solvent is ethyl acetate; and the catalyst is triphenylphosphine.

[0058] Example 3

[0059] A silicone release paper containing a heat-sensitive coating comprises a paper substrate, a heat-sensitive coating and a silicone release film layer, wherein the heat-sensitive coating is applied to the surface of the paper substrate, and the silicone release film layer is applied to the surface of the heat-sensitive coating. The silicone release film layer comprises the following raw materials in parts by weight:

[0060]

[0061] The curing agent is prepared by mixing silane-modified ester and isocyanate in a mass ratio of 8:3.7.

[0062] The preparation method of the modified hollow glass microspheres comprises the following steps:

[0063] S1. After mixing the epoxy soybean oil with the catalyst, a silane coupling agent is added, and the mixture is heated and stirred to obtain silane-modified epoxy soybean oil; wherein the heating and stirring is at a temperature of 73° C. and stirred for 2.7 hours; the silane coupling agent is KH-580; and the catalyst is azobisisobutyronitrile;

[0064] S2. Add hollow glass microspheres to silane-modified epoxy soybean oil, stir and mix, and then heat to react to obtain modified hollow glass microspheres; wherein the hollow glass microspheres are composed of three types of hollow glass microspheres with a diameter ratio of 6:9.5:17 and a weight ratio of 2:2.8:5.8; the heating reaction is carried out at a temperature of 87°C and a reaction time of 3.7 hours.

[0065] In the preparation method of the modified hollow glass microspheres, the mass ratio of the epoxidized soybean oil, the catalyst, the silane coupling agent and the hollow glass microspheres is 11.3:0.73:1.13:2.3.

[0066] The preparation method of the silane-modified ester comprises the following steps:

[0067] S11, stirring and mixing 2-methoxy-4-vinylphenol, 3-mercapto-1-propanol, and a photoinitiator, and reacting them under ultraviolet light to obtain a modified polyol; wherein the mass ratio of the 2-methoxy-4-vinylphenol, 3-mercapto-1-propanol, and the photoinitiator is 16.7:8.8:0.67; the photoinitiator is benzoin dimethyl ether; and the reaction time is 6.3 hours;

[0068] S12. The modified polyol, the acid anhydride compound and the catalyst are mixed, and after a temperature reaction, a silane coupling agent is added dropwise for 37 minutes, and the material is cooled and discharged to obtain a silane-modified ester; wherein the silane coupling agent is silane coupling agent A174; the temperature reaction is carried out at a temperature of 87°C for 2.7 hours; the mass ratio of the modified polyol, methacrylic anhydride and the catalyst is 10:17.3:0.27; the acid anhydride compound is maleic anhydride; and the catalyst is 4-dimethylaminopyridine.

[0069] The preparation method of the silicone release film layer includes the following steps: stirring and mixing epoxy soybean oil-modified acrylate, hydroxy polydimethylsiloxane, modified hollow glass microspheres, a solvent, a catalyst and n-butyl acrylate, heating to 57° C., reacting for 27 minutes, cooling to room temperature, adding a curing agent and fully mixing to obtain the silicone release film layer; the solvent is ethyl acetate; and the catalyst is triphenylphosphine.

[0070] Example 4

[0071] A silicone release paper containing a heat-sensitive coating comprises a paper substrate, a heat-sensitive coating and a silicone release film layer, wherein the heat-sensitive coating is applied to the surface of the paper substrate, and the silicone release film layer is applied to the surface of the heat-sensitive coating. The silicone release film layer comprises the following raw materials in parts by weight:

[0072]

[0073] The curing agent is prepared by mixing silane-modified ester and isocyanate in a mass ratio of 10:4.

[0074] The preparation method of the modified hollow glass microspheres comprises the following steps:

[0075] S1. After mixing the epoxy soybean oil and the catalyst, a silane coupling agent is added, and the mixture is heated and stirred to obtain silane-modified epoxy soybean oil; wherein the heating and stirring is at a temperature of 80° C. and stirred for 3 hours; the silane coupling agent is KH-580; and the catalyst is azobisisobutyronitrile;

[0076] S2. Add hollow glass microspheres to silane-modified epoxy soybean oil, stir and mix, and then heat to react to obtain modified hollow glass microspheres; wherein the hollow glass microspheres are composed of three types of hollow glass microspheres with a diameter ratio of 6.5:10:18 and a weight ratio of 2:3.0:6.2; the heating reaction is carried out at a temperature of 90°C and a reaction time of 4 hours.

[0077] In the preparation method of the modified hollow glass microspheres, the mass ratio of the epoxidized soybean oil, the catalyst, the silane coupling agent and the hollow glass microspheres is 12:0.8:1.2:2.5.

[0078] The preparation method of the silane-modified ester comprises the following steps:

[0079] S11, stirring and mixing 2-methoxy-4-vinylphenol, 3-mercapto-1-propanol, and a photoinitiator, and reacting them under ultraviolet light to obtain a modified polyol; wherein the mass ratio of the 2-methoxy-4-vinylphenol, 3-mercapto-1-propanol, and the photoinitiator is 17:9.0:0.7; the photoinitiator is benzoin dimethyl ether; and the reaction time is 7 hours;

[0080] S12. The modified polyol, the acid anhydride compound and the catalyst are mixed, and after a temperature reaction, a silane coupling agent is added dropwise for 40 minutes, and the material is cooled and discharged to obtain a silane-modified ester; wherein the silane coupling agent is silane coupling agent A174; the temperature reaction is at a temperature of 90°C and the reaction is carried out for 3 hours; the mass ratio of the modified polyol, methacrylic anhydride and the catalyst is 10:18:0.3; the acid anhydride compound is maleic anhydride; and the catalyst is 4-dimethylaminopyridine.

[0081] The preparation method of the silicone release film layer comprises the following steps: mixing epoxy soybean oil-modified acrylate, hydroxy polydimethylsiloxane, modified hollow glass microspheres, a solvent, a catalyst and n-butyl acrylate, heating to 60° C., reacting for 30 minutes, cooling to room temperature, adding a curing agent and fully mixing to obtain the silicone release film layer; the solvent is ethyl acetate; and the catalyst is triphenylphosphine.

[0082] Comparative Example 1

[0083] Compared with Example 2, the difference is that Comparative Example 1 does not use silane-modified ester, and the other components, preparation steps and parameters are the same.

[0084] Comparative Example 2

[0085] Compared with Example 2, the difference is that no isocyanate is used in Comparative Example 2, and the other components, preparation steps and parameters are the same.

[0086] Comparative Example 3

[0087] Compared with Example 2, the difference is that Comparative Example 3 uses hollow glass microspheres instead of modified hollow glass microspheres, and the other components, preparation steps and parameters are the same.

[0088] Comparative Example 4

[0089] Compared with Example 2, the difference is that comparative example 4 does not use modified hollow glass microspheres, and the other components, preparation steps and parameters are the same.

[0090] Comparative Example 5

[0091] Compared with Example 2, the difference is that Comparative Example 5 uses maleic anhydride instead of silane-modified ester, and the other components, preparation steps and parameters are the same.

[0092] Comparative Example 6

[0093] Compared with Example 2, the difference is that no silane coupling agent is used in step S12 of Comparative Example 6, and the other components, preparation steps and parameters are the same.

[0094] Comparative Example 7

[0095] Compared with Example 2, the difference is that Comparative Example 7 does not use hydroxypolydimethylsiloxane, and the other components, preparation steps and parameters are the same.

[0096] Comparative Example 8

[0097] Compared with Example 2, the difference is that the hollow glass microspheres of Comparative Example 8 are composed of two hollow glass microspheres with a diameter ratio of 9:16 and a weight ratio of 2.6:5.4, and the other components, preparation steps and parameters are the same.

[0098] Comparative Example 9

[0099] Compared with Example 2, the difference is that the hollow glass microspheres of Comparative Example 9 are composed of two hollow glass microspheres with a diameter ratio of 5.5:16 and a weight ratio of 2:5.4, and the other components, preparation steps and parameters are the same.

[0100] Comparative Example 10

[0101] Compared with Example 2, the difference is that the hollow glass microspheres of Comparative Example 10 are composed of two hollow glass microspheres with a diameter ratio of 5.5:9 and a weight ratio of 2:2.6, and the other components, preparation steps and parameters are the same.

[0102] The silicone release film layers prepared in Examples 1-4 and Comparative Examples 1-10 were subjected to the following tests, and the test results are shown in Table 1.

[0103] Adhesion Test: The adhesion between the prepared silicone release film and the substrate was tested using the GB / T 9286-1998 standard. A 10x10 grid pattern was cut into the coating surface using a blade. 3M tape was applied to the cut grid pattern. The tape was vigorously rubbed with an eraser to ensure adhesion. Grasp one end of the tape and tear it off at a 90° angle to test the coating's adhesion.

[0104] Wear resistance test:

[0105] A substrate coated with the silicone release film prepared in the present invention is placed horizontally, and a piece of 320-grit sandpaper with an area of ​​approximately 1 / 3 of the silicone release film layer is placed on its surface. A glass plate with an area equivalent to the sandpaper is placed on the adhesive surface of the sandpaper, and the sandpaper and the glass plate are adhered together by the adhesive to prevent relative sliding between the two. Finally, a weight is placed on the glass plate to ensure that the polydimethylsiloxane amphiphobic coating is in contact with the sandpaper surface. The sandpaper is moved at a speed of v = 0.5 mm / s, and the minimum weight corresponding to the scratch depth of the polydimethylsiloxane amphiphobic coating surface ≥ 1 μm is recorded to measure the wear resistance of the coating.

[0106] Table 1

[0107]

[0108]

[0109] From the test results in Table 1, it can be seen that compared with Comparative Examples 1-10, the adhesion performance and wear resistance of the silicone release film layers prepared in Examples 1-5 of the present invention are significantly better than those in Comparative Examples 1-10.

[0110] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to equivalent embodiments using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A silicone release paper containing a heat-sensitive coating, comprising a paper substrate, a heat-sensitive coating and a silicone release film layer, wherein the heat-sensitive coating is coated on the surface of the paper substrate, and the silicone release film layer is coated on the surface of the heat-sensitive coating, characterized in that: The organic silicon release film layer comprises the following raw materials in parts by weight: Epoxy soybean oil modified acrylate 20-40 parts 30-50 parts of hydroxy polydimethylsiloxane Modified hollow glass microspheres 10-15 parts Solvent 20-30 parts Catalyst 1-5 parts n-Butyl acrylate 0.1-0.3 parts 10-12 parts of curing agent; The curing agent is prepared by mixing silane-modified ester and isocyanate in a mass ratio of 5-10:3-4; The preparation method of the modified hollow glass microspheres comprises the following steps: S1, mixing the epoxy soybean oil with the catalyst, adding a silane coupling agent, heating and stirring, and obtaining silane-modified epoxy soybean oil; S2, adding hollow glass microspheres to the silane-modified epoxy soybean oil, stirring and mixing, and then heating to react to obtain modified hollow glass microspheres; The hollow glass microspheres are composed of three types of hollow glass microspheres with a diameter ratio of 5.0-6.5:8.5-10:15-18 and a weight ratio of 2:2.4-3.0:5.0-6.2; The preparation method of the silane-modified ester comprises the following steps: S11, stirring and mixing 2-methoxy-4-vinylphenol, 3-mercapto-1-propanol and a photoinitiator, and reacting them under ultraviolet light to obtain a modified polyol; S12, mixing the modified polyol, the acid anhydride compound and the catalyst, performing a temperature-raising reaction, and then dropping a silane coupling agent for 30-40 minutes, cooling and discharging the material to obtain a silane-modified ester.

2. The silicone release paper containing a heat-sensitive coating according to claim 1, characterized in that: In step S1, the heating and stirring is performed at a temperature of 60-80° C. and stirring for 2-3 hours; the silane coupling agent is KH-580; and the catalyst is azobisisobutyronitrile.

3. The silicone release paper containing a heat-sensitive coating according to claim 1, characterized in that: In step S2, the heating reaction is carried out at a temperature of 80-90°C for 3-4 hours.

4. The silicone release paper containing a heat-sensitive coating according to claim 1, characterized in that: In the preparation method of the modified hollow glass microspheres, the mass ratio of the epoxy soybean oil, the catalyst, the silane coupling agent and the hollow glass microspheres is 10-12: 0.6-0.8: 1.0-1.2: 2.0-2.

5.

5. The silicone release paper containing a heat-sensitive coating according to claim 1, characterized in that: In step S11, the mass ratio of 2-methoxy-4-vinylphenol, 3-mercapto-1-propanol and photoinitiator is 16-17:8.5-9.0:0.6-0.7; the photoinitiator is benzoin dimethyl ether; and the reaction time is 5-7 hours.

6. The silicone release paper containing a heat-sensitive coating according to claim 1, characterized in that: In step S12, the silane coupling agent is silane coupling agent A174; the temperature rise reaction is carried out at a temperature of 80-90° C. for 2-3 hours; the acid anhydride compound is one or both of maleic anhydride and itaconic anhydride; and the catalyst is 4-dimethylaminopyridine.

7. The silicone release paper containing a heat-sensitive coating according to claim 1, characterized in that: The preparation method of the silicone release film layer comprises the following steps: mixing epoxy soybean oil modified acrylate, hydroxy polydimethylsiloxane, modified hollow glass microspheres, solvent, catalyst and n-butyl acrylate, heating to 50-60°C, reacting for 20-30 minutes, cooling to room temperature, adding a curing agent and mixing thoroughly to obtain the release film layer; the solvent is ethyl acetate; and the catalyst is triphenylphosphine.

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