Release agent, release film and preparation method thereof

Abstract

The invention discloses a release agent, a release film and a preparation method of the release agent. The release agent comprises the following components in parts by weight: 1000 parts of organic silicon resin, 5000 parts of a solvent, 7-20 parts of a cross-linking agent, 3-7 parts of an anchoring agent, 14-25 parts of a catalyst and 1-4 parts of a light stripping agent, and the cross-linking agent is hydrogen-containing organic siloxane. The release film comprises a base material and a release layer arranged on the base material, and the release layer is formed by a release agent. The release film prepared from the release agent provided by the invention has the advantages of low release, stable release force, small aging increase and low price.

Description

Technical Field

[0001] The invention belongs to the technical field of release films, and in particular relates to a release agent, a release film and a preparation method thereof. Background Art

[0002] With the rapid development of science and technology, the demand for thermally conductive silicone sheets is increasing, and its production process requires a release film with a separation effect. However, traditional silicone release films used on thermally conductive silicone sheets often have local wrinkles due to the release film's inability to withstand the temperature, or bubbles are generated during lamination, or it cannot be torn apart and the die-cutting edges are warped. Therefore, in the process of making thermally conductive silicone, fluorine release films are often used as the base material for processing. With the fierce competition in the industry, in order to increase the unit price advantage of the product while reducing the cost of using materials, many customers require the development of low-cost silicone release films to replace fluorine release films because the unit price of fluorine release films is too high.

[0003] However, the basic system of silicone release film and thermal conductive silicone is the same. After long-term bonding, mutual penetration will occur at the bonding interface, resulting in the phenomenon of being unable to release. Therefore, the current silicone release film needs to be further improved.

[0004] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0005] The object of the present invention is to provide a release agent, a release film and a preparation method thereof. The release film has stable performance, low increase in release force after high-temperature aging and low cost.

[0006] In order to achieve the above object, a technical solution provided by a specific embodiment of the present invention is as follows:

[0007] A release agent comprises the following components in parts by weight: 1000 parts of an organic silicone resin, 5000 parts of a solvent, 7 to 20 parts of a crosslinking agent, 3 to 7 parts of an anchoring agent, 14 to 25 parts of a catalyst and 1 to 4 parts of a light stripping agent;

[0008] The crosslinking agent is hydrogen-containing organosiloxane.

[0009] In one or more embodiments of the present invention, the anchoring agent is vinyl siloxane.

[0010] In one or more embodiments of the present invention, the catalyst is a platinum complex.

[0011] In one or more embodiments of the present invention, the solvent is selected from at least one of toluene, 120# gasoline, isopropanol, ethyl acetate, butanone, and n-heptane.

[0012] In one or more embodiments of the present invention, the light stripping agent is selected from at least one of Elkem ADD398, Dow 7200, and Wacker R2.

[0013] Another specific embodiment of the present invention provides a technical solution as follows:

[0014] A method for preparing a release agent comprises the steps of adding an organic silicon resin into a solvent, mixing the mixture, and then sequentially adding a crosslinking agent, an anchoring agent, a catalyst and a light stripping agent, mixing the mixture, and obtaining the release agent.

[0015] Another specific embodiment of the present invention provides a technical solution as follows:

[0016] A release film comprises a substrate and a release layer arranged on the substrate, wherein the release layer is formed by the release agent.

[0017] In one or more embodiments of the present invention, the amount of the release agent on the substrate is 0.3 to 0.5 g / m 2 .

[0018] In one or more embodiments of the present invention, the substrate has a thickness of 25 to 100 μm.

[0019] Another specific embodiment of the present invention provides a technical solution as follows:

[0020] A method for preparing a release film comprises the following steps:

[0021] Coating a release agent on the substrate, and drying at 90 to 140° C. for 20 to 40 seconds to obtain a release film;

[0022] The release agent is the above release agent, and the coating amount of the release agent on the substrate is 0.3-0.5 g / m 2 .

[0023] Compared with the prior art, the release film of the present invention has stable release performance, low increase in release force due to high-temperature aging, low cost, and after being bonded with thermally conductive silicone, penetration is not likely to occur at the bonding interface, thus meeting market demand. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 Schematic diagram of the structure of a release film in one embodiment of the present invention.

[0026] Description of main reference numerals:

[0027] 1. Substrate; 2. Release layer. DETAILED DESCRIPTION

[0028] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0029] A specific embodiment of the present invention provides a release agent, comprising the following components in parts by weight: 1000 parts of silicone resin, 5000 parts of solvent, 7-20 parts of crosslinking agent, 3-7 parts of anchoring agent, 14-25 parts of catalyst and 1-4 parts of light stripping agent; the crosslinking agent is hydrogen-containing organosiloxane.

[0030] Specifically, silicone resin has good release properties and high temperature resistance. The solid content can be selected from 30 to 100%. Specific models can be RS720 (Ekem), SL200 (Dow), 752 (Dow), 7458 (Dow), and D955 (Wacker).

[0031] The specific types of cross-linking agents can be selected from the following models: 7672 (Dow), 7028 (Dow), 7253 (Eken), V60 (Wacker). The cross-linking agent bridges between linear molecules, allowing multiple linear molecules to bond to each other to form a network structure, which can trigger free radical reactions, decompose to generate free radicals, and then trigger free chain reactions of polymers, causing polymers to cross-link, thereby improving the strength, heat resistance, corrosion resistance, wear resistance, solvent resistance, water resistance, pressure resistance, scratch resistance and other properties of the material.

[0032] Furthermore, the anchoring agent is vinyl siloxane, which is used to improve the adhesion of the release agent to the substrate and improve the adhesion of the coating. The specific types of anchoring agents can be 297 (Dow), 9176 (Dow), 11AP (Wacker), and AD38 (Elkem).

[0033] Furthermore, the catalyst is a platinum complex, which is used to accelerate the reaction rate, improve the degree of curing, and effectively ensure the conversion rate and reaction selectivity of the product, thereby improving the performance of the finished product. The specific catalyst models can be 4000 (Dow), C05 (Wacker), and PL-85 (Elkem).

[0034] Furthermore, the light stripping agent is a siloxane mixture, which is used to adjust the stripping force of the coating. Specific models can be selected from ADD398 (Ekem), 7200 (Dow), and R2 (Wacker).

[0035] Furthermore, the solvent is selected from at least one of toluene, 120# gasoline, isopropanol, ethyl acetate, butanone, and n-heptane.

[0036] Another specific embodiment of the present invention provides a method for preparing the release agent, which comprises adding an organic silicone resin into a solvent, mixing evenly, and then sequentially adding a crosslinking agent, an anchoring agent, a catalyst and a light stripping agent, mixing evenly, to obtain the release agent.

[0037] Another specific embodiment of the present invention provides a release film, such as Figure 1 As shown, it includes a substrate 1 and a release layer 2 arranged on the substrate 1, and the release layer 2 is formed by the above-mentioned release agent.

[0038] Specifically, the substrate 1 is a 25-100 μm transparent PET substrate, and the amount of the release agent on the substrate 1 is 0.3-0.5 g / m 2 After the release film is bonded to the thermally conductive silicone sheet, the bonding interface is not prone to mutual penetration, showing the advantages of low release, stable release force, and small aging increase.

[0039] Another specific embodiment of the present invention provides a method for preparing the above release film, which comprises coating a release agent on a substrate and drying the substrate at 90 to 140° C. for 20 to 40 seconds to obtain the release film.

[0040] Specifically, based on the weight of silicon in the release agent, the coating amount of the release agent on the substrate is 0.3 to 0.5 g / m 2 Preferably, after drying, aging at 50° C. for 24 hours helps to make the release film more stable.

[0041] The present invention is further described in detail below in conjunction with specific embodiments.

[0042] Example 1

[0043] The release agent, in parts by weight, includes 1000 parts of RS720 (Akem), 5000 parts of toluene, 15 parts of 7253 (Akem), 5 parts of 297 (Dow), 20 parts of C05 (Wacker) and 4 parts of ADD398 (Akem).

[0044] Add toluene to RS720 (Akem), stir thoroughly to dissolve, then add 7253 (Akem), 297 (Dow), C05 (Wacker) and ADD398 (Akem) in sequence, stir evenly to obtain the release agent.

[0045] Take a 100μm thick transparent PET substrate and use 0.3g / m 2 The release agent was coated on the substrate, dried at 100° C. for 30 seconds, and then aged at 50° C. for 24 hours to obtain a release film.

[0046] Example 2

[0047] The release agent, in parts by weight, includes 1000 parts of 7458 (Dow), 5000 parts of toluene, 10 parts of 7028 (Dow), 5 parts of 11AP (Wacker), 20 parts of 4000 (Dow) and 4 parts of ADD398 (Aiken).

[0048] Add toluene to 7458 (Dow) and stir thoroughly to dissolve, then add 7028 (Dow), 11AP (Wacker), 4000 (Dow) and ADD398 (Aiken) in sequence and stir evenly to obtain the release agent.

[0049] Take a 100μm thick transparent PET substrate and use 0.3g / m 2 The release agent was coated on the substrate, dried at 100° C. for 30 seconds, and then aged at 50° C. for 24 hours to obtain a release film.

[0050] Comparative Example 1

[0051] The release agent, in parts by weight, includes 1000 parts of RS720 (Akem), 5000 parts of toluene, 30 parts of 7253 (Akem), 5 parts of 297 (Dow), 20 parts of C05 (Wacker) and 4 parts of ADD398 (Akem).

[0052] Add toluene to RS720 (Akem), stir thoroughly to dissolve, then add 7253 (Akem), 297 (Dow), C05 (Wacker) and ADD398 (Akem) in sequence, stir evenly to obtain the release agent.

[0053] Take a 100μm thick transparent PET substrate and use 0.3g / m 2 The release agent was coated on the substrate, dried at 100° C. for 30 seconds, and then aged at 50° C. for 24 hours to obtain a release film.

[0054] Comparative Example 2

[0055] The release agent, in parts by weight, includes 1000 parts of RS720 (Akem), 5000 parts of toluene, 2 parts of 7253 (Akem), 5 parts of AD38 (Akem), 20 parts of PL-85 (Akem) and 4 parts of ADD398 (Akem).

[0056] Add toluene to RS720 (Akem), stir thoroughly to dissolve, then add 7253 (Akem), AD38 (Akem), PL-85 (Akem) and ADD398 (Akem) in sequence, stir evenly to obtain the release agent.

[0057] Take a 100μm thick transparent PET substrate and use 0.3g / m 2 The release agent was coated on the substrate, dried at 100° C. for 30 seconds, and then aged at 50° C. for 24 hours to obtain a release film.

[0058] Comparative Example 3

[0059] The release agent, in parts by weight, includes 1000 parts of 7458 (Dow), 5000 parts of toluene, 25 parts of 7028 (Dow), 5 parts of 11AP (Wacker), 20 parts of 4000 (Dow) and 4 parts of ADD398 (Aiken).

[0060] Add toluene to 7458 (Dow) and stir thoroughly to dissolve, then add 7028 (Dow), 11AP (Wacker), 4000 (Dow) and ADD398 (Aiken) in sequence and stir evenly to obtain the release agent.

[0061] Take a 100μm thick transparent PET substrate and use 0.3g / m 2 The release agent was coated on the substrate, dried at 100° C. for 30 seconds, and then aged at 50° C. for 24 hours to obtain a release film.

[0062] The release films in each embodiment and each comparative example and the fluorine release film purchased from Kunshan Sibek Precision Composite Materials Co., Ltd. were tested respectively. Three samples of each release film were taken for repeated testing. The specific tests are as follows:

[0063] (1) TESA7475 release force test: Fix the release film on the test plate, put the TESA7475 adhesive side down on the release film, press it back and forth twice with a roller at a speed of 10mm / s, and place it at a certain temperature for a certain time. Debug the equipment peeling angle to 180°, set the speed to 300mm / min, and start the test.

[0064] The test conditions are 23℃ for 20min, 23℃ for 24h and 70℃ for 24h respectively. The release force is qualified if it meets 3-5g / 25mm.

[0065] (2) Apply Nitto 31B tape to the release film according to the standard method. Also apply Nitto 31B tape to a blank Teflon film according to the standard method as a standard blank sample. 2The standard stainless steel was pressed in an oven at 70°C for 20 hours and then taken out and placed at room temperature for 1 hour.

[0066] The Nitto 31B tape was peeled off from the release film and attached to a blank PET film. The test was conducted 24 hours later. The tensile force at a stretching speed of 30 cm / min and a stretching angle of 180 degrees was the tensile force for peeling off the test tape.

[0067] Tear off the Nitto 31B tape from the blank Teflon and stick it on the blank PET film. Test it after 24 hours. The tensile force at a stretching speed of 30 cm / min and a stretching angle of 180 degrees is the tensile force of the blank standard sample.

[0068] Calculate the residual bonding rate: residual bonding rate (%) = (tensile force of peeling test tape / tensile force of blank standard sample)*100%.

[0069] Table 1 Test results

[0070]

[0071]

[0072] Compared with Comparative Examples 1 and 2, the amount of the release film raw materials in Example 1 is within the range specified in the present invention. In the test, the release film in Example 1 has excellent performance and is close to the performance of the fluorine release film. The amount of the crosslinking agent in Comparative Examples 1 and 2 exceeds the range specified in the present invention, and the high-temperature release force of the release film increases greatly, which cannot meet the requirements.

[0073] Compared with Example 2, the amount of crosslinking agent used in Comparative Example 3 exceeds the range specified by the present invention, and the high-temperature release force also increases greatly, which cannot meet the requirements. However, the performance of the release film in Example 2 is not much different from that of the fluorine release film, and the performance is excellent. In addition, from the perspective of price, the price of the release film in Examples 1 and 2 of the present invention is only 1.2 to 1.8 yuan / m 2 , while the price of fluorine release film is 8 to 16 yuan / m 2 The release film in the embodiment of the present invention has a more advantageous price and excellent performance. Therefore, the release film disclosed in the present invention has a cheaper cost and good release performance, which can meet market demand.

[0074] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

[0075] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A release agent, characterized in that: The invention comprises the following components by weight: 1000 parts of organic silicone resin, 5000 parts of solvent, 7-20 parts of cross-linking agent, 3-7 parts of anchoring agent, 14-25 parts of catalyst and 1-4 parts of light stripping agent; The crosslinking agent is hydrogen-containing organosiloxane.

2. The release agent according to claim 1, characterized in that The anchoring agent is vinyl siloxane.

3. The release agent according to claim 1, characterized in that The catalyst is a platinum complex.

4. The release agent according to claim 1, characterized in that: The solvent is selected from at least one of toluene, 120# gasoline, isopropanol, ethyl acetate, butanone, and n-heptane.

5. The release agent according to claim 1, characterized in that: The light stripping agent is selected from at least one of Elkem ADD398, Dow 7200, and Wacker R2.

6. A method for preparing the release agent according to any one of claims 1 to 5, characterized in that: Add the organic silicone resin into the solvent, mix well, then add the cross-linking agent, anchoring agent, catalyst and light stripping agent in sequence, mix well, and obtain the release agent.

7. A release film, characterized in that: The invention comprises a substrate and a release layer arranged on the substrate, wherein the release layer is formed by the release agent according to any one of claims 1 to 5.

8. The release film according to claim 7, characterized in that: Based on the weight of silicon in the release agent, the amount of release agent used on the substrate is 0.3-0.5 g / m 2 .

9. The release film according to claim 7, characterized in that: The substrate has a thickness of 25 to 100 μm.

10. A method for preparing a release film, characterized in that: The steps include: Coating a release agent on the substrate, and drying at 90 to 140° C. for 20 to 40 seconds to obtain a release film; The release agent is the release agent according to any one of claims 1 to 5, and the coating amount of the release agent on the substrate is 0.3 to 0.5 g / m 2 .

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