阅读说明：本技术 离型层组合物和包含其固化产物的离型膜 (Release composition and release film comprising cured product thereof ) 是由 朴俊莹 沈慧珍 李相律 尹敬准 徐光洙 柳英昌 于 2019-09-17 设计创作，主要内容包括：本发明涉及具有适当的离型剥离力的离型膜以及能够提供其的离型层组合物。(The present invention relates to a release film having an appropriate release peeling force and a release layer composition capable of providing the same.)

1. A release layer composition comprising:

a phenyl-containing silicone-based resin; a silicone-based crosslinking agent; a silane coupling agent; a metal catalyst; and a solvent, wherein the solvent is a mixture of,

wherein the silicone-based crosslinking agent is contained in an amount of 1.5 parts by weight to 4.5 parts by weight, based on 100 parts by weight of the phenyl-containing silicone-based resin.

2. The release layer composition according to claim 1, wherein the silane coupling agent is contained in an amount of 1.5 to 4.5 parts by weight based on 100 parts by weight of the phenyl-containing silicone-based resin.

3. The release layer composition according to claim 1, wherein the content of the metal catalyst is 3 to 9.5 parts by weight based on 100 parts by weight of the phenyl-containing silicone-based resin.

4. The release layer composition of claim 1, wherein the phenyl-containing silicone-based resin is contained in an amount of 1 to 15 parts by weight based on 100 parts by weight of the solvent.

5. The release layer composition of claim 1, wherein the phenyl-containing silicone-based resin has a molar ratio between silicon-bonded phenyl groups and silicon-bonded hydrogen of from 1:1 to 1: 1.5.

6. The release layer composition according to claim 1, wherein the phenyl-containing silicone-based resin has a viscosity of 5000cps to 10000 cps.

7. The release layer composition according to claim 1, wherein the phenyl-containing silicone-based resin has a weight average molecular weight of 50000g/mol to 150000 g/mol.

8. A release film comprising:

a substrate; and

a release layer disposed on one surface of the substrate and comprising a cured product of the release layer composition of claim 1.

9. The release film according to claim 8, wherein the release layer satisfies the following equation 1:

[ equation 1]

20％≤{(X–Y)/Y}×100≤35％

Wherein

X represents the release peel force of the release layer measured after attaching the release layer to a Tesa7475 standard adhesive tape and storing the attached release layer at 25 ℃ for 1 day, and

y represents the release peel force of the release layer measured after attaching the release layer to a Tesa7475 standard adhesive tape and storing the attached release layer at 60 ℃ for 7 days.

10. The release film according to claim 8, wherein the release layer has a release peel force of 500 to 1250 gf/inch, as measured after attaching the release layer to the Tesa7475 standard adhesive tape and storing the attached release layer at 25 ℃ for 1 day.

11. The release film according to claim 8, wherein the release layer has a release peel force of 1200 gf/inch to 1650 gf/inch as measured after attaching the release layer to the Tesa7475 standard adhesive tape and storing the attached release layer at 60 ℃ for 7 days.

12. The release film according to claim 8, wherein the surface energy of the release layer is 25 to 35 mN/m.

Technical Field

The present specification claims the benefit of the application date of korean patent application No. 10-2018-0115902, filed by 28.9.2018 to the korean intellectual property office, the entire contents of which are incorporated herein by reference.

The present invention relates to a release layer composition and a release film comprising a cured product thereof.

Background

The release film is used in various fields including display units such as liquid crystal displays, plasma displays, personal digital assistants and navigation systems, organic light emitting diodes, polymer light emitting diodes, and polarizing plates, coating fields, adhesion promoter fields, and adhesive fields. The release film may function primarily to protect the surface of the target article, the surface of the tackifier or the surface of the adhesive, or as a carrier for the target article. The release film may be attached to the target article during production, transport and storage of the target article, but may be removed from the target article during production of the final article.

In recent years, Paint Protection Film (PPF) is used to protect the appearance of automobiles and the like, and the demand for this has increased. PPF consists of a substrate (e.g., a polyurethane film) and an adhesive layer. In order to manufacture a PPF, a substrate, such as a polyurethane film manufactured in sheet form, must be laminated with an adhesive layer. To manufacture the polyurethane film, a release film as a molding base is used. However, if a substrate (e.g., a polyurethane film) for PPF is formed on a release film, a tunneling phenomenon (tunneling phenomenon) occurs in which the substrate itself (e.g., the polyurethane film) is rapidly peeled off from the release film since the release film has no stickiness or adhesive force. If this phenomenon occurs, there arise problems in that the quality as a PPF product is degraded and the difficulty in the production process is increased. Further, if a substrate is formed on an untreated PET film which is not subjected to a release treatment in order to prevent such a problem, there arises a problem in that the substrate is not easily peeled from the PET film, and thus it is difficult to use the PET film as a product.

Therefore, development of a release film that allows easy manufacture of a film (e.g., PPF) is required.

Disclosure of Invention

Technical problem

The present invention aims to provide a release film having an appropriate release peeling force and a release layer forming composition capable of providing the same.

However, the problems to be solved by the present invention are not limited to the above-mentioned problems, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

Technical scheme

One embodiment of the present invention provides a release layer composition comprising: a phenyl-containing silicone-based resin; a silicone-based crosslinking agent; a silane coupling agent; a metal catalyst; and a solvent, wherein the content of the silicone-based crosslinking agent is 1.5 parts by weight to 4.5 parts by weight based on 100 parts by weight of the phenyl-containing silicone-based resin.

Another embodiment of the present invention provides a release film comprising: a substrate; and a release layer disposed on one surface of the substrate and including a cured product of the release layer composition.

Advantageous effects

The release layer composition according to one embodiment of the present invention has an appropriate release peeling force, and thus can provide a release film suitable for manufacturing films used in various fields.

The release film according to one embodiment of the present invention has an appropriate release peel force, and thus has an advantage in that it is suitable for manufacturing films used in various fields.

The effects of the present invention are not limited to the above-described effects, and those not mentioned will be clearly understood from the present specification and the accompanying drawings by those skilled in the art.

Detailed Description

Throughout this specification, it will be understood that when any part is referred to as "comprising" any component, it does not exclude other components, but may also comprise other components, unless stated otherwise.

Throughout this specification, when any member is referred to as being "on" another member, it refers not only to the case where any member is in contact with another member, but also to the case where a third member is present between the two members.

Throughout this specification, the unit "parts by weight" may refer to the weight ratio between the components.

Throughout this specification, "a and/or B" means "a and B, or a or B".

Throughout this specification, the molecular weight and molecular weight distribution of a compound may be used to calculate the "weight average molecular weight" and "number average molecular weight" of any compound. Specifically, the molecular weight and molecular weight distribution of the compound can be obtained by: placing Tetrahydrofuran (THF) and the compound in a 1-ml glass vial to prepare a test sample having a concentration of the compound of 1 wt%; the standard sample (polystyrene) and the test sample were filtered through a filter (pore size: 0.45 mm); injecting each sample filtrate into a GPC injector; and the elution time of the test sample is compared to the calibration curve for the standard sample. At this time, Infinity II 1260(Agilent Technologies, Inc.) may be used as a measuring instrument, and the flow rate and the column temperature may be set to 1.00 mL/min and 40.0 ℃.

Throughout the present specification, the number of moles of silicon-bonded phenyl groups contained in the silicone-based resin and the number of moles of silicon-bonded hydrogen in the silicone-based resin may be calculated from a graph measured using a Nuclear Magnetic Resonance (NMR) spectrometer (Oxford 300NMR, VARIAN).

Throughout this specification, the release peel force of a release layer may refer to an average force to peel the release layer obtained by: the release layer was pressed and attached to a Tesa7475 standard adhesive tape by 3 reciprocations of 2kg load, the attached release layer was stored at a set temperature for a set time, and then a release peel force was measured at a predetermined peel speed by using a peel force tester (AR-1000, chemistruments).

Throughout this specification, the viscosity of a compound may be a value measured by a Brookfield viscometer (DV-II + PRO viscometer) at a temperature of 25 ℃.

Hereinafter, the present specification will be described in more detail.

One embodiment of the present invention provides a release layer composition comprising: a phenyl-containing silicone-based resin; a silicone-based crosslinking agent; a silane coupling agent; a metal catalyst; and a solvent, wherein the content of the silicone-based crosslinking agent is 1.5 parts by weight to 4.5 parts by weight based on 100 parts by weight of the phenyl-containing silicone-based resin.

The release layer composition according to one embodiment of the present invention has an appropriate release peeling force, and thus can provide a release film suitable for manufacturing films used in various fields. Specifically, the release film may be applied to a Paint Protection Film (PPF) used as an automobile exterior protection film.

In the present invention, the release film may refer to a film used in various fields including the fields of automobiles (e.g., automobile exterior protective films), display units such as liquid crystal displays, plasma displays, personal digital assistants and navigation systems, organic light emitting diodes, polymer light emitting diodes and polarizing plates, the field of coatings, the field of tackifiers and the field of adhesives, and may function to protect the surface of a target article, the surface of a tackifier or the surface of an adhesive, or as a carrier of a target article, or may be used as a base film for manufacturing a certain film, and may be removed from a certain film. Further, a release film may refer to a film that is attached to a target article during production, transportation, and storage of the target article, but is removed from the target article during production of the final article.

According to one embodiment, the phenyl group-containing silicone-based resin may be a resin in which phenyl groups are bonded to groups of a silicone skeleton. In addition, at least one of an unsaturated alkyl group, a saturated alkyl group, and hydrogen may be bonded to a group of the silicone skeleton of the phenyl-containing silicone-based resin. Specifically, the phenyl-containing silicone-based resin may contain phenyl groups, unsaturated alkyl groups, saturated alkyl groups, and hydrogen.

Further, the organosilicon backbone may contain silicon atoms and oxygen atoms, and covalent bonds may be formed between groups of silicon atoms and groups of phenyl groups. As described above, at least one of an unsaturated alkyl group, a saturated alkyl group, and hydrogen may be bonded to the group of the silicone skeleton. Further, the silicone skeleton may have a linear or branched structure.

According to an embodiment of the present invention, in the silicone-based resin containing a phenyl group, the molar ratio between the silicon-bonded phenyl group and the silicon-bonded hydrogen may be 1:1 to 1: 1.5. Specifically, in the phenyl group-containing silicone-based resin, the molar ratio between the silicon-bonded phenyl groups and the silicon-bonded hydrogen atoms may be 1:1 to 1:1.4, 1:1 to 1:1.3, or 1:1.1 to 1: 1.3. The release layer composition comprising the phenyl group-containing silicone-based resin in which the ratio of the number of moles of phenyl groups bonded to silicon atoms to the number of moles of hydrogen atoms bonded to silicon atoms satisfies the above range can provide a release film comprising a release layer having an appropriate surface energy and release peel force. In the case of a release film formed from a release agent composition comprising a conventional silicone-based resin containing only vinyl groups, there is a problem in that a tunneling phenomenon occurs in which a film formed on the release film is easily peeled from the release film, or the film is not easily peeled from the release film, and thus the release peel force of the release film is not easily controlled.

However, according to one embodiment of the present invention, since the phenyl group-containing silicone-based resin in which the ratio of the number of moles of phenyl groups bonded to silicon atoms to the number of moles of hydrogen atoms bonded to silicon atoms satisfies the above-described range is used, the release film has an appropriate release peeling force, and thus the above-described tunneling phenomenon and the phenomenon in which the film formed on the release film is not peeled from the release film can be effectively suppressed. That is, the release layer composition is advantageous in that it can provide a release film having excellent properties as a release film. In particular, the release film comprising the cured product of the release layer composition may be a release film specifically used for manufacturing a finish protective film.

According to an embodiment of the present invention, the viscosity of the phenyl-containing silicone-based resin may be 5,000cps to 10,000 cps. Specifically, the viscosity of the phenyl-containing silicone-based resin may be 5,000cps to 10,000cps, 6,000cps to 9,000cps, or 7,000cps to 8,500cps, as measured at a temperature of 25 ℃, a humidity of 50 RH%, and a frequency of 30 Hz. The phenyl group-containing silicone-based resin having a viscosity within the above range is easily miscible with the silicone-based crosslinking agent, the silane coupling agent, the metal catalyst and the solvent, and thus a release film having uniform quality can be provided.

According to an embodiment of the present invention, the weight average molecular weight of the phenyl-containing silicone-based resin may be 50,000g/mol to 150,000 g/mol. Specifically, the weight average molecular weight of the phenyl-containing silicone-based resin can be 70,000 to 140,000g/mol, 85,000 to 135,000g/mol, or 100,000 to 130,000 g/mol. When the weight average molecular weight of the phenyl-containing silicone-based resin is within the above range, the surface energy of the release layer comprising the cured product of the release layer composition can be effectively prevented from excessively increasing or decreasing. In addition, when the weight average molecular weight of the phenyl-containing silicone-based resin is within the above range, the release layer comprising the cured product of the release layer composition may have a suitable level of release peel force.

According to an embodiment of the present invention, the phenyl group-containing silicone-based resin may be contained in an amount of 1 part by weight to 15 parts by weight, based on 100 parts by weight of the solvent. Specifically, the phenyl-containing silicone-based resin may be contained in an amount of 5 to 12.5 parts by weight, 7.5 to 10 parts by weight, or 8 to 12 parts by weight, based on 100 parts by weight of the solvent. When the content of the phenyl group-containing silicone-based resin is controlled within the above range, the release layer composition may be more easily cured. In addition, when the content of the phenyl group-containing silicone-based resin is within the above range, the release layer comprising the cured product of the release layer composition may have appropriate surface energy and release peel force.

According to an embodiment of the present invention, the content of the silicone-based crosslinking agent may be 1.5 parts by weight to 4.5 parts by weight, 2 parts by weight to 4 parts by weight, 1.5 parts by weight to 3.5 parts by weight, 2 parts by weight to 3.5 parts by weight, or 2 parts by weight to 2.5 parts by weight, based on 100 parts by weight of the phenyl-containing silicone-based resin. When the content of the silicone-based crosslinking agent is controlled within the above range, it is possible to effectively prevent the release peeling force of the release layer from excessively increasing. In particular, when the content of the silicone-based crosslinking agent is within the above range, the release peeling force of the release layer can be prevented from being greatly increased even if the release film is stored under high temperature conditions for a long time. In addition, durability of the release film comprising the cured product of the release layer composition can be improved. In addition, when the content of the silicone-based crosslinking agent is within the above range, curability deterioration of the release layer composition can be prevented. Therefore, the release layer composition can suppress deterioration of the release property (i.e., release property) of the release layer.

According to an embodiment of the present invention, as the silicone-based crosslinking agent, a silicone-based crosslinking agent used for preparing a release agent composition in the art may be selected without limitation. For example, the silicone-based crosslinking agent may include a polyorganohydrogensiloxane having at least two silicon atom-bonded hydrogen atoms in one molecule. In particular, the silicone-based crosslinker may include at least one of: dimethylhydrogensiloxy terminated dimethylsiloxane-methylhydrogensiloxane copolymer, trimethylsiloxy terminated poly (methylhydrogensiloxane), poly (hydrogen silsesquioxane), and methylhydrogensiloxane, but the kind of silicone-based crosslinking agent is not limited thereto. In the present invention, methylhydrogensiloxane can be used as the silicone-based crosslinking agent.

According to an embodiment of the present invention, the content of the silane coupling agent may be 1.5 parts by weight to 4.5 parts by weight based on 100 parts by weight of the phenyl group-containing silicone-based resin. Specifically, the content of the silane coupling agent may be 2 to 4 parts by weight, 2 to 3 parts by weight, or 1.5 to 3 parts by weight, based on 100 parts by weight of the phenyl-containing silicone-based resin. When the content of the silane coupling agent is controlled within the above range, the durability of the release layer may be improved, and a phenomenon that the film disposed on the release layer is not peeled may be effectively prevented.

According to an embodiment of the present invention, as the silane coupling agent, a silane coupling agent used for preparing a release agent composition in the art may be selected without limitation. For example, the silane coupling agent may include at least one of an amino-based silane coupling agent, an epoxy-based silane coupling agent, and a mercapto-based silane coupling agent. Further, the silane coupling agent may include at least one of: vinyltrimethoxysilane, vinylphenyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, gamma-methacryloxypropyltrimethoxysilane, gamma-glycidoxypropyltrimethoxysilane, 4-glycidylbutyltrimethoxysilane, gamma-aminopropyltriethoxysilane, N-beta- (aminoethyl) -gamma-aminopropyltrimethoxysilane, N-3- (4- (3-aminopropoxy) methoxy) propyl-3-aminopropyltrimethoxysilane, imidazolesilane, triazinesilane, gamma-mercaptopropyltrimethoxysilane and vinyltrimethoxysilane. However, the kind of the silane coupling agent is not limited to the above silane coupling agent. In the present invention, vinyltrimethoxysilane can be used as the silane coupling agent. Further, as the silane coupling agent, a mixture of two or more silane coupling agents may be used.

According to an embodiment of the present invention, the content of the metal catalyst may be 3 parts by weight to 9.5 parts by weight based on 100 parts by weight of the phenyl-containing silicone-based resin. Specifically, the content of the metal catalyst may be 3 to 9.5 parts by weight, 3.5 to 9 parts by weight, 4 to 8 parts by weight, or 5 to 6.5 parts by weight, based on 100 parts by weight of the phenyl-containing silicone-based resin. Specifically, the metal catalyst functions to promote a curing reaction between the phenyl-containing silicone-based resin and the silicone-based crosslinking agent. When the content of the metal catalyst is controlled within the above range, the release layer composition can be effectively inhibited from being uncured or being excessively cured.

According to an embodiment of the present invention, as the metal catalyst, a metal catalyst used for preparing a mold release composition in the art may be selected and used without limitation. Specifically, the metal catalyst may include at least a platinum-based catalyst. Further, the platinum-based catalyst may include at least one of: particulate platinum, particulate platinum adsorbed on a carbon powder carrier, chloroplatinic acid, alcohol-modified chloroplatinic acid, and olefin complexes of chloroplatinic acid, but the kind of the platinum-based catalyst is not limited thereto. In the present invention, PL-50T (Shin-Etsu Silicone Co., Ltd.) can be used as the platinum-based catalyst.

According to an embodiment of the present invention, the solvent may be at least one of toluene, xylene, hexane, heptane, methyl ethyl ketone, and ethyl acetate. However, the solvent is not limited thereto, and may be freely selected from organic solvents generally known in the art.

According to one embodiment of the present invention, the solid content of the release layer composition may be 0.5% to 30%. Specifically, the solid content of the release layer composition may be 1% to 25%, 5% to 20%, 10% to 15%, 1% to 5%, 8% to 15%, or 20% to 28%.

According to an embodiment of the present invention, when the solid content of the release layer composition is controlled within the above range, the release layer composition can be easily applied. In addition, the viscosity of the release layer composition can be prevented from rapidly increasing during curing of the composition, thereby preventing the wettability of the composition from being reduced during application. Specifically, when the solid content of the release layer composition is within the above range, the content of the phenyl-containing silicone-based resin in the release layer composition may be relatively low, and thus the durability of the cured product of the release layer composition may be prevented from being lowered. In addition, since the viscosity of the release layer composition is rapidly increased during curing, it is possible to effectively prevent the surface smoothness of the cured product from being lowered.

According to an embodiment of the present invention, the release layer composition may further include other additives including at least one of a release agent, silica particles, and a photoinitiator. However, the kind of other additives is not limited thereto, and known components used in the art may be used.

According to one embodiment of the present invention, the release layer composition may be cured by photo-curing or thermal curing. Specifically, the release layer composition may be thermally cured, and the thermal curing of the release layer composition may be performed at a temperature of 100 ℃ to 180 ℃ for 30 seconds to 180 seconds. When the curing temperature and curing time of the release layer composition are controlled within the above ranges, the release layer composition can be stably cured, and thus the durability of the cured product can be improved.

One embodiment of the present invention provides a release film comprising: a substrate; and a release layer disposed on one surface of the substrate and including a cured product of the release layer composition.

The release film according to one embodiment of the present invention has an appropriate release peel force, and thus has an advantage in that it is suitable for manufacturing films used in various fields.

According to an embodiment of the present invention, the release film may include a release layer and a substrate, and the release layer may include a cured product of the release layer composition.

According to an embodiment of the present invention, a release film including a release layer disposed on one surface of a substrate may be provided by applying a release layer composition on one surface of the substrate and curing the applied composition. As a method of applying the release layer composition on one surface of the substrate, a known method can be used. Specifically, an inkjet printing method, a dispensing method, a screen printing method, a spray coating method, a spin coating method, a doctor blade coating method, a dip coater coating method, a Mayer rod coating method, a gravure coating method, a micro-gravure coating method, or the like can be used.

According to one embodiment of the invention, the substrate may comprise at least one of: polyethylene resin, polyethylene terephthalate resin, polyether ether ketone resin, polyimide resin, polypropylene resin, stretched polypropylene resin, cellulose, and polyvinyl chloride resin, but the kind of the substrate is not limited thereto.

According to an embodiment of the present invention, the substrate may have a thickness of 5 μm to 200 μm. The release film including the substrate having a thickness within the above range may have excellent durability.

According to an embodiment of the present invention, the thickness of the release layer may be 0.01 μm to 10 μm. The release film including the release layer having a thickness within the above range may have an appropriate release peel force.

According to an embodiment of the present invention, the release layer may satisfy the following equation 1.

[ equation 1]

20％≤{(X–Y)/Y}×100≤35％

In the above equation 1, X represents a release peel force of the release layer measured after attaching the release layer to the Tesa7475 standard adhesive tape and storing the attached release layer at 25 ℃ for 1 day, and Y represents a release peel force of the release layer measured after attaching the release layer to the Tesa7475 standard adhesive tape and storing the attached release layer at 60 ℃ for 7 days.

That is, the release peel force of the release layer stored at 60 ℃ for 7 days after attachment to the Tesa7475 standard adhesive tape (release peel force after heat treatment) may vary by 20% to 35% from the release peel force of the release layer stored at 25 ℃ for 1 day after attachment (initial release peel force). Specifically, the change in release peel force after the heat treatment relative to the initial release peel force may be 22% to 34%, 20% to 25%, or 30% to 35%. When the variation of the release peel force after the heat treatment of the release layer with respect to the initial release peel force satisfies the above range, there is an advantage in that the release film including the release layer can maintain the release property at an appropriate level even under high temperature conditions. That is, the release film may be exposed to various conditions after being disposed on an actual product, and in particular, the release film may maintain a proper level of release performance even when exposed to a high temperature condition.

Further, when the variation of the release peel force after the heat treatment with respect to the initial release peel force satisfies the above range, the amount of unreacted compound remaining in the release layer is small, indicating that the release layer has uniform quality.

According to an embodiment of the present invention, the release peel force of the release layer may be measured under a humidity condition of 50 RH% at a peel speed of 0.3 m/min and a peel angle of 180 ° after the release layer is attached to the Tesa7475 standard adhesive tape and stored at a set temperature for a set time.

According to an embodiment of the present invention, the release peel force of the release layer may be 500 gf/inch to 1,250 gf/inch when measured after the release layer is attached to the Tesa7475 standard adhesive tape and stored at 25 ℃ for 1 day. The release film including the release layer satisfying the above range in release peel force after storage for 1 day at 25 ℃ has a suitable level of release peel force, and thus, tunneling phenomenon and non-peeling phenomenon of the film formed on the release layer can be suppressed.

According to an embodiment of the present invention, the release peel force of the release layer may be 1,200 gf/inch to 1,650 gf/inch when measured after the release layer is attached to the Tesa7475 standard adhesive tape and stored at 60 ℃ for 7 days. The release film including the release layer having a release peel force after storage at 60 ℃ for 7 days satisfying the above range has an advantage in that it can exhibit excellent release properties even under high temperature conditions. That is, the tunneling phenomenon and the non-peeling phenomenon of the film formed on the release layer can be suppressed even under high temperature conditions.

According to an embodiment of the present invention, the surface energy of the release layer may be 25mN/m to 35 mN/m. The release film including the release layer having the surface energy satisfying the above range may have a release peeling force of an appropriate level.

According to one embodiment of the present invention, a release film may be applied to the paint protective film. In particular, the release film may be applied to a process for manufacturing and transporting a paint protective film. More specifically, the urethane resin layer (base for paint protective film) may be formed on the release layer by applying a urethane resin composition capable of forming the base film for paint protective film on the release layer of the release film and curing the urethane resin composition. Next, since the release layer has an appropriate release peeling force, it is possible to suppress the occurrence of a phenomenon in which the substrate of the finish protective film is not peeled from the release layer and a tunneling phenomenon, and thus, the substrate of the finish protective film can be easily peeled from the release layer.

EMBODIMENTS FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in detail with reference to examples. However, the embodiment according to the present invention may be modified into various different forms, and the scope of the present invention should not be construed as being limited to the embodiment described below. The embodiments of the present description are provided to more fully explain the present invention to those skilled in the art.

Production of release film