High-temperature-resistant flame-retardant release film and preparation process thereof

Abstract

The invention relates to the technical field of release films, in particular to a high-temperature-resistant flame-retardant release film and a preparation process thereof.The high-temperature-resistant flame-retardant release film comprises a silicone oil layer, a base material layer, an adhesive layer, a high-temperature-resistant film layer, a nano high-temperature-resistant ceramic coating, a flame-retardant coating and a protective layer which are sequentially arranged from bottom to top; the nano high-temperature-resistant ceramic coating is formed by coating and curing a nano high-temperature-resistant ceramic coating, and the flame-retardant coating is formed by coating and curing a flame-retardant coating. According to the high-temperature-resistant flame-retardant release film disclosed by the invention, the high-temperature-resistant film layer and the nano high-temperature-resistant ceramic coating formed by coating and curing the nano high-temperature-resistant ceramic coating are adopted, so that the high-temperature-resistant flame-retardant release film has good strength and toughness, excellent high-temperature resistance and good transparency and base material adhesive force; and the flame-retardant coating formed by coating and curing the flame-retardant coating is adopted, so that the flame-retardant coating has excellent flame-retardant performance, and does not generate toxic and harmful gas or gas with pungent smell during combustion.

Description

Technical Field

[0001] The invention relates to the technical field of release films, and in particular to a high temperature resistant flame retardant release film and a preparation process thereof. Background Art

[0002] Release film refers to a film with a distinguishable surface. When the release film comes into contact with a specific material under limited conditions, it is non-sticky or slightly sticky. Some existing release films have poor high temperature resistance and flame retardancy.

[0003] The Chinese invention patent with application number 202210844501.2 discloses an insulating flame-retardant release film and its preparation process, wherein the insulating flame-retardant release film comprises a silicone oil layer, an antistatic coating, a substrate layer, a flame-retardant coating, an insulating layer and a protective layer arranged in sequence from bottom to top, wherein the flame-retardant coating is an inorganic flame retardant layer, and the insulating layer is a polyimide / montmorillonite nanocomposite film. The insulating flame-retardant release film of the patent has a good flame retardant effect, but also has the defect of poor high temperature resistance. Summary of the invention

[0004] In order to overcome the shortcomings and deficiencies in the prior art, the object of the present invention is to provide a high temperature resistant flame retardant release film and a preparation process thereof.

[0005] The purpose of the present invention is achieved through the following technical solutions: A high temperature resistant flame retardant release film, comprising a silicone oil layer, a substrate layer, an adhesive layer, a high temperature resistant film layer, a nano high temperature resistant ceramic coating, a flame retardant coating and a protective layer arranged in sequence from bottom to top, wherein the nano high temperature resistant ceramic coating is formed by curing the nano high temperature resistant ceramic coating after coating, and the flame retardant coating is formed by curing the flame retardant coating after coating. The silicone oil layer is formed by UV curing after coating with solvent-free silicone oil, the substrate layer is a PET film with a light transmittance greater than 92% and a haze less than 1%, the adhesive layer is a water-based acrylic adhesive layer, the high temperature resistant film layer is a high temperature resistant PMMA film, and the protective layer is a degradable biaxially oriented polylactic acid film.

[0006] The high temperature resistant flame retardant release film of the present invention has good strength and toughness, excellent high temperature resistance, good transparency and substrate adhesion by adopting a high temperature resistant film layer and a nano high temperature resistant ceramic coating formed by coating and curing the nano high temperature resistant ceramic coating; and the flame retardant coating formed by coating and curing the flame retardant coating has excellent flame retardant properties, does not generate toxic or harmful gases or irritating gases when burned, and also has excellent mechanical properties, thermal stability, adhesion, water resistance and weather resistance.

[0007] Preferably, the nano-high temperature resistant ceramic coating comprises the following raw materials in parts by weight: 20-40 parts of aqueous non-ionic polyurethane emulsion, 10-30 parts of epoxy acrylic resin, 10-20 parts of polydimethylsiloxane, 5-15 parts of trimethoxymethylsilane, 6-10 parts of tetraethyl orthosilicate, 8-12 parts of nano-ceramic powder, 4-8 parts of hexagonal boron nitride powder, 2-6 parts of aramid fiber, 1.5-2.5 parts of initiator, 2-4 parts of other additives and 20-30 parts of deionized water. The nano-high temperature resistant ceramic coating of the present invention adopts the above raw materials and strictly controls the weight ratio of each raw material, so that the obtained nano-high temperature resistant ceramic coating has good strength and toughness, as well as excellent high temperature resistance, and has good transparency and substrate adhesion.

[0008] Preferably, the nano ceramic powder is a mixture of nano silicon carbide, nano aluminum nitride, nano magnesium oxide, nano calcium fluoride and nano barium carbonate in a mass ratio of 3-5: 2-4: 1.5-2.5: 0.5-1.5: 1. The present invention strictly controls the type, compounding and ratio of the nano ceramic powder to obtain a nano high temperature resistant ceramic coating with good strength and toughness, as well as excellent high temperature resistance.

[0009] Preferably, the initiator is a mixture of 2-methyl-2-(4-morpholinyl)-1-[4-(methylthio)phenyl]-1-propanone and 1-hydroxycyclohexylphenyl ketone in a weight ratio of 1-2: 1. The present invention can initiate the polymerization reaction at a lower temperature by strictly controlling the type, compounding and ratio of the initiator, thereby increasing the reaction rate and reducing energy consumption.

[0010] Preferably, the other auxiliary agent is a mixture of polyoxyethylene alkyl ether hydrogen sulfate, mercapto-modified polydimethylsiloxane and tripropylene glycol n-butyl ether in a weight ratio of 1.5-2.5:0.5-1.5:1. The present invention adopts polyoxyethylene alkyl ether hydrogen sulfate as an emulsifier, which has a good emulsification effect, can improve the stability of the coating, and ensure the smooth progress of emulsion polymerization. The present invention adopts mercapto-modified polydimethylsiloxane as a leveling agent, which can effectively reduce the surface tension of the coating, improve its leveling and uniformity, and improve the permeability of the coating. The present invention adopts tripropylene glycol n-butyl ether as a film-forming aid, which has good film-forming properties, compatibility and excellent substrate adhesion.

[0011] Preferably, the flame retardant coating comprises the following raw materials in parts by weight: 25-45 parts of aqueous acrylic emulsion, 15-25 parts of styrene acrylic emulsion, 15-25 parts of tributyl borate, 10-20 parts of aqueous isocyanate modified hyperbranched polyester light-curing resin, 5-15 parts of vinyl resin, 4-8 parts of composite flame retardant, 1-3 parts of initiator, 5-10 parts of other auxiliary agents and 25-45 parts of deionized water. The flame retardant coating of the present invention adopts the above raw materials and strictly controls the weight ratio of each raw material, so that the flame retardant coating has excellent flame retardant properties, does not generate toxic or harmful gases or irritating odors when burning, and also has excellent mechanical properties, thermal stability, bonding properties, water resistance and weather resistance.

[0012] Preferably, the initiator is a mixture of 2-hydroxy-2-methyl-1-[4-(2-hydroxyethoxy)phenyl]-1-propanone and 2,4,6-trimethylbenzoyl-diphenylphosphine oxide in a weight ratio of 1-2: 1. The present invention can initiate the polymerization reaction at a lower temperature by strictly controlling the type, compounding and ratio of the initiator, thereby increasing the reaction rate and reducing energy consumption.

[0013] Preferably, the composite flame retardant is a mixture of brominated epoxy resin, resorcinol bis(diphenyl phosphate) and magnesium hydroxide in a weight ratio of 1-2: 0.8-1.2: 1. The present invention strictly controls the type, compounding and ratio of the composite flame retardant, so that the flame retardant coating has excellent flame retardant properties and does not generate toxic or harmful gases or irritating gases when burning.

[0014] Preferably, the other auxiliary agents are a mixture of polyoxyethylene hardened castor oil fatty acid ester, trimethylsiloxysilicate and polyoxyethylene polyoxypropylene pentaerythritol ether in a weight ratio of 1-2:0.5-1.5:1. The present invention adopts polyoxyethylene alkyl ether hydrogen sulfate as an emulsifier, which has a good emulsification effect, can improve the stability of the coating, and ensure the smooth progress of emulsion polymerization. The present invention adopts trimethylsiloxysilicate as a dispersant to enhance gloss, increase leveling effect, improve tinting power, reduce viscosity, reduce flocculation, and increase storage stability. The present invention adopts polyoxyethylene polyoxypropylene pentaerythritol ether as a defoaming agent, which has the characteristics of fast defoaming speed, long anti-foaming time, good effect, good diffusivity, good permeability, good thermal stability, etc.

[0015] Another object of the present invention is achieved by the following technical solution: A process for preparing a high temperature resistant flame retardant release film, comprising the following steps:

[0016] (1) laminating the high temperature resistant film layer on the front side of the substrate layer through the adhesive layer;

[0017] (2) applying a layer of nano-high temperature resistant ceramic coating on the surface of the high temperature resistant film layer, and forming a nano-high temperature resistant ceramic coating after curing;

[0018] (3) applying a layer of flame retardant coating on the surface of the nano high temperature resistant ceramic coating, forming a flame retardant coating after curing, and then compounding a protective layer;

[0019] (4) A layer of silicone oil is coated on the back of the substrate layer, and a silicone oil layer is formed after curing to obtain a high temperature resistant flame retardant release film.

[0020] The preparation process of the invention has simple steps, convenient operation and control, stable quality, high production efficiency, low production cost and can be produced on a large scale in an industrial manner.

[0021] The beneficial effects of the present invention are as follows: the high temperature resistant flame retardant release film of the present invention has good strength and toughness, as well as excellent high temperature resistance, and has good transparency and substrate adhesion by adopting a high temperature resistant film layer and a nano high temperature resistant ceramic coating formed by coating and curing the nano high temperature resistant ceramic coating; and the flame retardant coating formed by coating and curing the flame retardant coating has excellent flame retardant properties, does not generate toxic or harmful gases or gases with irritating odors when burned, and also has excellent mechanical properties, thermal stability, adhesion properties, water resistance and weather resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a partial cross-sectional view of the high temperature resistant flame retardant release film of the present invention.

[0023] The reference numerals in the drawings are: silicone oil layer 1, high temperature resistant coating 2, substrate layer 3, flame retardant coating 4, insulating layer 5, and protective layer 6. DETAILED DESCRIPTION

[0024] In order to facilitate the understanding of those skilled in the art, the following embodiments and attached Figure 1 The present invention is further described, and the contents mentioned in the implementation modes are not intended to limit the present invention.

[0025] Example 1

[0026] A high temperature resistant flame retardant release film comprises a silicone oil layer 1, a substrate layer 2, an adhesive layer 3, a high temperature resistant film layer 4, a nano high temperature resistant ceramic coating 5, a flame retardant coating 6 and a protective layer 7 which are arranged in sequence from bottom to top, wherein the nano high temperature resistant ceramic coating 5 is formed by curing the nano high temperature resistant ceramic coating after coating, and the flame retardant coating 6 is formed by curing the flame retardant coating after coating. The silicone oil layer 1 is formed by UV curing after coating with solvent-free silicone oil, the substrate layer 2 is a PET film with a light transmittance greater than 92% and a haze less than 1%, the adhesive layer 3 is a water-based acrylic adhesive layer, the high temperature resistant film layer 4 is a high temperature resistant PMMA film, and the protective layer 7 is a degradable biaxially oriented polylactic acid film.

[0027] The nano high-temperature resistant ceramic coating includes the following raw materials in parts by weight: 20 parts of aqueous non-ionic polyurethane emulsion, 10 parts of epoxy acrylic resin, 10 parts of polydimethylsiloxane, 5 parts of trimethoxymethylsilane, 6 parts of tetraethyl orthosilicate, 8 parts of nano ceramic powder, 4 parts of hexagonal boron nitride powder, 2 parts of aramid fiber, 1.5 parts of initiator, 2 parts of other additives and 20 parts of deionized water.

[0028] The nano ceramic powder is a mixture of nano silicon carbide, nano aluminum nitride, nano magnesium oxide, nano calcium fluoride and nano barium carbonate in a mass ratio of 3:2:1.5:0.5:1.

[0029] The initiator is a mixture of 2-methyl-2-(4-morpholinyl)-1-[4-(methylthio)phenyl]-1-propanone and 1-hydroxycyclohexylphenyl ketone in a weight ratio of 1:1.

[0030] The other auxiliary agent is a mixture of polyoxyethylene alkyl ether hydrogen sulfate, mercapto-modified polydimethylsiloxane and tripropylene glycol n-butyl ether in a weight ratio of 1.5:0.5:1.

[0031] The flame retardant coating comprises the following raw materials in parts by weight: 25 parts of water-based acrylic emulsion, 15 parts of styrene acrylic emulsion, 15 parts of tributyl borate, 10 parts of water-based isocyanate-modified hyperbranched polyester photocurable resin, 5 parts of vinyl resin, 4 parts of composite flame retardant, 1 part of initiator, 5 parts of other additives and 25 parts of deionized water.

[0032] The initiator is a mixture of 2-hydroxy-2-methyl-1-[4-(2-hydroxyethoxy)phenyl]-1-propanone and 2,4,6-trimethylbenzoyl-diphenylphosphine oxide in a weight ratio of 1:1.

[0033] The composite flame retardant is a mixture of brominated epoxy resin, resorcinol bis(diphenyl phosphate) and magnesium hydroxide in a weight ratio of 1:0.8:1.

[0034] The other auxiliary agent is a mixture of polyoxyethylene hardened castor oil fatty acid ester, trimethylsiloxysilicate and polyoxyethylene polyoxypropylene pentaerythritol ether in a weight ratio of 1:0.5:1.

[0035] A preparation process of a high temperature resistant flame retardant release film comprises the following steps:

[0036] (1) affixing a high temperature resistant film layer 4 to the front surface of the substrate layer 2 via an adhesive layer 3;

[0037] (2) coating a layer of nano-high temperature resistant ceramic coating on the surface of the high temperature resistant film layer 4, and forming a nano-high temperature resistant ceramic coating 5 after curing;

[0038] (3) coating a layer of flame retardant coating on the surface of the nano high temperature resistant ceramic coating 5, forming a flame retardant coating 6 after curing, and then compounding a protective layer 7;

[0039] (4) A layer of silicone oil is coated on the back of the substrate layer 2, and after curing, a silicone oil layer 1 is formed to obtain a high temperature resistant flame retardant release film.

[0040] Example 2

[0041] The difference between this embodiment and the above-mentioned embodiment 1 is that:

[0042] The nano high-temperature resistant ceramic coating includes the following raw materials in parts by weight: 30 parts of aqueous non-ionic polyurethane emulsion, 20 parts of epoxy acrylic resin, 15 parts of polydimethylsiloxane, 10 parts of trimethoxymethylsilane, 8 parts of tetraethyl orthosilicate, 10 parts of nano ceramic powder, 6 parts of hexagonal boron nitride powder, 4 parts of aramid fiber, 2 parts of initiator, 3 parts of other additives and 25 parts of deionized water.

[0043] The nano ceramic powder is a mixture of nano silicon carbide, nano aluminum nitride, nano magnesium oxide, nano calcium fluoride and nano barium carbonate in a mass ratio of 4:3:2:1:1.

[0044] The initiator is a mixture of 2-methyl-2-(4-morpholinyl)-1-[4-(methylthio)phenyl]-1-propanone and 1-hydroxycyclohexylphenyl ketone in a weight ratio of 1.5:1.

[0045] The other auxiliary agent is a mixture of polyoxyethylene alkyl ether hydrogen sulfate, mercapto-modified polydimethylsiloxane and tripropylene glycol n-butyl ether in a weight ratio of 2:1:1.

[0046] The flame retardant coating comprises the following raw materials in parts by weight: 35 parts of water-based acrylic emulsion, 20 parts of styrene acrylic emulsion, 20 parts of tributyl borate, 15 parts of water-based isocyanate-modified hyperbranched polyester photocurable resin, 10 parts of vinyl resin, 6 parts of composite flame retardant, 2 parts of initiator, 8 parts of other additives and 35 parts of deionized water.

[0047] The initiator is a mixture of 2-hydroxy-2-methyl-1-[4-(2-hydroxyethoxy)phenyl]-1-propanone and 2,4,6-trimethylbenzoyl-diphenylphosphine oxide in a weight ratio of 1.5:1.

[0048] The composite flame retardant is a mixture of brominated epoxy resin, resorcinol bis(diphenyl phosphate) and magnesium hydroxide in a weight ratio of 1.5:1:1.

[0049] The other auxiliary agent is a mixture of polyoxyethylene hardened castor oil fatty acid ester, trimethylsiloxysilicate and polyoxyethylene polyoxypropylene pentaerythritol ether in a weight ratio of 1.5:1:1.

[0050] Example 3

[0051] The difference between this embodiment and the above-mentioned embodiment 1 is that:

[0052] The nano high-temperature resistant ceramic coating includes the following raw materials in parts by weight: 40 parts of aqueous non-ionic polyurethane emulsion, 30 parts of epoxy acrylic resin, 20 parts of polydimethylsiloxane, 15 parts of trimethoxymethylsilane, 10 parts of tetraethyl orthosilicate, 12 parts of nano ceramic powder, 8 parts of hexagonal boron nitride powder, 6 parts of aramid fiber, 2.5 parts of initiator, 4 parts of other additives and 30 parts of deionized water.

[0053] The nano ceramic powder is a mixture of nano silicon carbide, nano aluminum nitride, nano magnesium oxide, nano calcium fluoride and nano barium carbonate in a mass ratio of 5:4:2.5:1.5:1.

[0054] The initiator is a mixture of 2-methyl-2-(4-morpholinyl)-1-[4-(methylthio)phenyl]-1-propanone and 1-hydroxycyclohexylphenyl ketone in a weight ratio of 2:1.

[0055] The other auxiliary agent is a mixture of polyoxyethylene alkyl ether hydrogen sulfate, mercapto-modified polydimethylsiloxane and tripropylene glycol n-butyl ether in a weight ratio of 2.5:1.5:1.

[0056] The flame retardant coating comprises the following raw materials in parts by weight: 45 parts of water-based acrylic emulsion, 25 parts of styrene acrylic emulsion, 25 parts of tributyl borate, 20 parts of water-based isocyanate-modified hyperbranched polyester photocurable resin, 15 parts of vinyl resin, 8 parts of composite flame retardant, 3 parts of initiator, 10 parts of other additives and 45 parts of deionized water.

[0057] The initiator is a mixture of 2-hydroxy-2-methyl-1-[4-(2-hydroxyethoxy)phenyl]-1-propanone and 2,4,6-trimethylbenzoyl-diphenylphosphine oxide in a weight ratio of 2:1.

[0058] The composite flame retardant is a mixture of brominated epoxy resin, resorcinol bis(diphenyl phosphate) and magnesium hydroxide in a weight ratio of 2:1.2:1.

[0059] The other auxiliary agent is a mixture of polyoxyethylene hardened castor oil fatty acid ester, trimethylsiloxysilicate and polyoxyethylene polyoxypropylene pentaerythritol ether in a weight ratio of 2:1.5:1.

[0060] Comparative Example 1

[0061] The difference between this comparative example and Example 2 is that no nano ceramic powder is added.

[0062] Comparative Example 2

[0063] The difference between this comparative example and Example 2 is that no composite flame retardant is added.

[0064] The performance tests of the high temperature resistant coatings obtained in Examples 1-3 are as follows:

[0065]

[0066] As can be seen from the above table, the high temperature resistant flame retardant release film of the present invention adopts a high temperature resistant film layer and a nano high temperature resistant ceramic coating formed by coating and curing the nano high temperature resistant ceramic coating. It has good strength and toughness, as well as excellent high temperature resistance, and also has good transparency and substrate adhesion.

[0067] The performance tests of the flame retardant coatings obtained in Examples 1-3 are as follows:

[0068] Test items Test Standards Example 1 Example 2 Example 3 Comparative Example 2 Flame retardant grade GB / T 2408-2008 V0 V0 V0 V2 Adhesion GB / T 5210-2006 5B 5B 5B 5B Light transmittance GB / T 9754-2007 93.8％ 94.5％ 94.2％ 94.6％

[0069] It can be seen from the above table that the high temperature resistant flame retardant release film of the present invention has excellent flame retardant properties by adopting a flame retardant coating formed by coating and curing the flame retardant coating, and does not produce toxic or harmful gases or irritating gases when burned. It also has excellent mechanical properties, thermal stability, adhesion, water resistance and weather resistance.

[0070] The above embodiments are preferred implementation schemes of the present invention. In addition, the present invention may also be implemented in other ways. Any obvious replacement without departing from the concept of the present invention is within the protection scope of the present invention.

Claims

1. A high temperature resistant flame retardant release film, characterized in that: It includes a silicone oil layer, a substrate layer, an adhesive layer, a high-temperature resistant film layer, a nano-high-temperature resistant ceramic coating, a flame retardant coating and a protective layer which are arranged in sequence from bottom to top. The nano-high-temperature resistant ceramic coating is formed by curing the nano-high-temperature resistant ceramic coating after coating, and the flame retardant coating is formed by curing the flame retardant coating after coating.

2. The high temperature resistant flame retardant release film according to claim 1, characterized in that: The nano high-temperature resistant ceramic coating comprises the following raw materials in parts by weight: 20-40 parts of aqueous non-ionic polyurethane emulsion, 10-30 parts of epoxy acrylic resin, 10-20 parts of polydimethylsiloxane, 5-15 parts of trimethoxymethylsilane, 6-10 parts of tetraethyl orthosilicate, 8-12 parts of nano ceramic powder, 4-8 parts of hexagonal boron nitride powder, 2-6 parts of aramid fiber, 1.5-2.5 parts of initiator, 2-4 parts of other additives and 20-30 parts of deionized water.

3. The high temperature resistant flame retardant release film according to claim 2, characterized in that: The nano ceramic powder is a mixture of nano silicon carbide, nano aluminum nitride, nano magnesium oxide, nano calcium fluoride and nano barium carbonate in a mass ratio of 3-5:2-4:1.5-2.5:0.5-1.5:

1.

4. The high temperature resistant flame retardant release film according to claim 2, characterized in that: The initiator is a mixture of 2-methyl-2-(4-morpholinyl)-1-[4-(methylthio)phenyl]-1-propanone and 1-hydroxycyclohexylphenyl ketone in a weight ratio of 1-2:

1.

5. The high temperature resistant flame retardant release film according to claim 2, characterized in that: The other auxiliary agent is a mixture of polyoxyethylene alkyl ether hydrogen sulfate, mercapto-modified polydimethylsiloxane and tripropylene glycol n-butyl ether in a weight ratio of 1.5-2.5:0.5-1.5:

1.

6. The high temperature resistant flame retardant release film according to claim 1, characterized in that: The flame retardant coating comprises the following raw materials in parts by weight: 25-45 parts of water-based acrylic emulsion, 15-25 parts of styrene acrylic emulsion, 15-25 parts of tributyl borate, 10-20 parts of water-based isocyanate-modified hyperbranched polyester photocurable resin, 5-15 parts of vinyl resin, 4-8 parts of composite flame retardant, 1-3 parts of initiator, 5-10 parts of other additives and 25-45 parts of deionized water.

7. The high temperature resistant flame retardant release film according to claim 6, characterized in that: The initiator is a mixture of 2-hydroxy-2-methyl-1-[4-(2-hydroxyethoxy)phenyl]-1-propanone and 2,4,6-trimethylbenzoyl-diphenylphosphine oxide in a weight ratio of 1-2:

1.

8. The high temperature resistant flame retardant release film according to claim 6, characterized in that: The composite flame retardant is composed of brominated epoxy resin, resorcinol bis(diphenyl phosphate) and magnesium hydroxide in a weight ratio of 1-2: A mixture of 0.8-1.2:

1.

9. The high temperature resistant flame retardant release film according to claim 6, characterized in that: The other auxiliary agent is a mixture of polyoxyethylene hardened castor oil fatty acid ester, trimethylsiloxysilicate and polyoxyethylene polyoxypropylene pentaerythritol ether in a weight ratio of 1-2:0.5-1.5:

1.

10. A process for preparing a high temperature resistant flame retardant release film according to any one of claims 1 to 9, characterized in that: The steps include: (1) laminating the high temperature resistant film layer on the front side of the substrate layer through the adhesive layer; (2) applying a layer of nano-high temperature resistant ceramic coating on the surface of the high temperature resistant film layer, and forming a nano-high temperature resistant ceramic coating after curing; (3) applying a layer of flame retardant coating on the surface of the nano high temperature resistant ceramic coating, forming a flame retardant coating after curing, and then compounding a protective layer; (4) A layer of silicone oil is coated on the back of the substrate layer, and a silicone oil layer is formed after curing to obtain a high temperature resistant flame retardant release film.

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