KR102306997B1 - Release film for ultra-light release - Google Patents

Abstract

The present invention relates to a cemented carbide release film, and more particularly, by using a polyester binder resin having low reactivity with polysiloxane and a resin containing an oxazoline group, has excellent adhesion to a substrate and solvent resistance, and minimizes change over time at high temperature in the release area It relates to a carbide release film capable of realizing a cemented carbide peeling that can be performed.

Description

Cemented carbide release film {RELEASE FILM FOR ULTRA-LIGHT RELEASE}

The present invention relates to a cemented carbide release film that has excellent adhesion to a substrate and solvent resistance and can minimize changes over time at high temperature in the release region even when a high-thickness release region is formed for realizing cemented carbide peeling.

In general, in the field of release films used for the function of protecting the pressure-sensitive adhesive layer, a release film with excellent solvent resistance to various solvents used in the pressure-sensitive adhesive is required.

To this end, a general method is used to improve the degree of crosslinking by using a platinum catalyst or a hydrolyzed silane oligomer having a reactive group to improve the degree of crosslinking of polysiloxane itself. Changes or problems such as a decrease in the residual adhesion rate occur.

In addition, there is a method of improving the adhesion of the substrate by adding a binder such as urethane, polyester, or acrylic to the coating solution (Korean Patent Application Laid-Open No. 10-2017-0099980), but in this case, it can act as a catalyst poison in the release layer configuration. Since it must be used by excluding chemical functional groups, there is a problem in that some loss in mold release properties occurs.

In particular, in the recent release film market, the need for a release film with very low peeling force is accelerating. (Korean Patent Laid-Open Patent Publication No. 10-2017-0067067), but in this case, there is a problem such as a change in peel force due to the occurrence of change over time at high temperature.

Therefore, there is an urgent need to develop a release film that has excellent solvent resistance and adhesion to a substrate and has little change over time for the realization of carbide peeling.

Korean Patent Publication 10-2017-0099980 Korean Patent Publication 10-2017-0067067

The present invention has been devised in order to solve the above problems and meet the requirements of the prior art, and an object of the present invention is to provide a light carbide release film having high adhesion to a substrate and high solvent resistance.

Another object of the present invention is to provide a cemented carbide release release film capable of minimizing the change over time at high temperature in the release region even when forming a release region with a high thickness for realization of carbide peeling.

These and other objects and advantages of the present invention will become more apparent from the following description of preferred embodiments.

The above object is a release film comprising a substrate and an application layer positioned on at least one surface of the substrate, wherein the application layer is made of a water-based release coating liquid, and is achieved by a carbide release film including an anchor region and a release region.

Here, the aqueous release coating solution may include vinyl polysiloxane, hydrogen polysiloxane, a polyester resin, an oxazoline group-containing resin, a platinum catalyst, a surfactant, and a solvent.

Preferably, the anchor region may be formed of a polyester resin and an oxazoline group-containing resin.

Preferably, it may contain 0.1 to 10 parts by weight of the oxazoline group-containing resin relative to 100 parts by weight of the polyester resin.

Preferably, the release region may be formed of vinylpolysiloxane and hydrogen polysiloxane.

Preferably, it may contain 110 to 200 parts by weight of the hydrogen polysiloxane based on 100 parts by weight of the vinylpolysiloxane.

Preferably, the solvent may include 80 wt% to 99 wt% of water and 1 wt% to 20 wt% of ethylene glycol.

Preferably, the aqueous release coating solution may further include an antistatic agent.

Preferably, the thickness after drying of the application layer may be 0.01 to 2.0 μm.

More preferably, the thickness of the coating layer after drying may be 0.5 to 1.0 μm.

Preferably, the cemented carbide release film is aged for 1 day at 60°C and 90% RH, and then the high temperature peeling force and the room temperature peeling force after aging for 1 day at room temperature may be 15 gf/in or less, respectively.

Preferably, the cemented carbide release film may have less than 10% difference in peel strength at room temperature after aging at 60° C. and 90% RH for 1 day and then aging at room temperature for 1 day.

Preferably, the cemented carbide release film may have a residual adhesive rate of 90% or more.

Preferably, the cemented carbide release film may be one in which the coating layer is not peeled off after wiping it back and forth three times with a sulphate immersed in isopropyl alcohol (IPA).

According to the present invention, there are effects such as excellent adhesion to the substrate and solvent resistance.

Furthermore, the present invention has an effect such as being able to minimize the change over time at high temperature of the release area even when forming a release area with a high thickness for realizing superhard peeling.

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

1 is a schematic cross-sectional view of a cemented carbide release film according to an embodiment of the present invention.
Figure 2 is a schematic cross-sectional view of a release film of cemented carbide according to another embodiment of the present invention.

Hereinafter, the present invention will be described in detail with reference to embodiments and drawings of the present invention. It will be apparent to those of ordinary skill in the art that these examples are only presented by way of example to explain the present invention in more detail, and that the scope of the present invention is not limited by these examples. .

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In case of conflict, the present specification, including definitions, will control. Also, although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, suitable methods and materials are described herein.

As used herein, "comprise", "comprising", "include", "including", "containing", "~ The terms "characterized by", "has", "having" or any other variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, article, or apparatus comprising a list of elements is not necessarily limited to only those elements, but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. may be Also, unless expressly stated to the contrary, "or" refers to an inclusive 'or' and not an exclusive 'or'.

First, the cemented carbide release film according to an embodiment of the present invention will be described in detail with reference to Figs.

Referring to FIG. 1 , a cemented carbide release film 100 according to an embodiment of the present invention is a release film including a substrate 10 and an application layer 20 positioned on at least one surface of the substrate, and the application layer 20 ) is formed by applying a water-based release coating solution, and may have a structure in which the anchor region 21 and the release region 22 of the application layer 20 alternate left and right.

In addition, referring to FIG. 2 , the cemented carbide release film 100 according to another embodiment of the present invention may have a structure in which the anchor region 21 and the release region 22 of the application layer 20 are in contact with the top and bottom. .

However, in FIGS. 1 and 2, the anchor region 21 and the release region 22 are shown in a physically completely separated state, but this is only for convenience of explanation and can be formed when the application layer is coated once. structure is shown. In addition, the boundary between the anchor region 21 and the release region 22 may not be clear from each other, the states of FIGS. 1 and 2 may be mixed, and the probability of being in the state of FIG. 2 rather than that of FIG. 1 probabilistically this is high

There is no particular limitation as the substrate 10, but it is preferable to use a polyethylene terephthalate film having excellent heat resistance, chemical resistance and mechanical strength, and economical efficiency. In particular, it is preferable that the film has a thickness of 10 to 200 μm.

In one embodiment, the aqueous release coating liquid constituting the application layer 20 includes vinyl polysiloxane, hydrogen polysiloxane, polyester resin, oxazoline group-containing resin, platinum catalyst, surfactant, and solvent, and After coating on one or both sides, the coating layer is formed by heating and curing.

In one embodiment, the anchor region 21 is formed of a polyester resin as a binder resin and an oxazoline group-containing resin as a curing agent in the aqueous release coating solution.

In addition, the polyester resin and the oxazoline group-containing resin forming the anchor region 21 are not particularly limited, and commercialized products widely used in the art may be used.

In the present invention, by using the polyester resin and the oxazoline group-containing resin forming the anchor region 21, the reaction with the polysiloxane constituting the coating solution can be minimized, thereby providing a release film with high adhesion to the substrate and high solvent resistance. have. In addition, even when forming a high-thickness release region for realizing cemented carbide peeling, it is possible to minimize changes over time at high temperature due to the anchor region 21 . That is, by preferentially inducing crosslinking of carboxylic acids in the polyester resin by using a polyester resin and an oxazoline group-containing resin, solvent resistance can be sufficiently ensured even though the degree of silicone crosslinking is not high. Since the release area is maintained soft rather than hard, it is possible to realize super-hardening peeling while having excellent solvent resistance.

In one embodiment, it is preferable to include 0.1 to 10 parts by weight of the oxazoline group-containing resin relative to 100 parts by weight of the polyester resin. If the oxazoline group-containing resin is less than 0.1 parts by weight, solvent resistance is deteriorated, whereas when it exceeds 10 parts by weight, there is a problem in that the silicone curing is inhibited and the release property of the film is insufficient.

In one embodiment, the release region 22 is formed by vinylpolysiloxane and hydrogen polysiloxane in the water-based release coating solution.

The vinyl polysiloxane emulsion and the hydrogen polysiloxane emulsion in the aqueous release coating solution are not particularly limited, and silicone emulsion products commonly used in the art may be used.

In one embodiment, it is preferable to include 110 to 200 parts by weight of the hydrogen polysiloxane based on 100 parts by weight of the vinylpolysiloxane. When the amount of the hydrogen polysiloxane is less than 110 parts by weight, there is a disadvantage in that the silicone transfer rate is high, whereas when it exceeds 200 parts by weight, there is a disadvantage in that stability with time change at high temperature is insufficient.

As described above, the cemented carbide release film according to the present invention can secure excellent silicone curing properties even at 130° C. to 150° C., which is a coating drying condition, by controlling the ratio of vinyl polysiloxane and hydrogen polysiloxane.

In addition, the platinum catalyst is not particularly limited, and commercialized products widely used in the art may be used.

In one embodiment, the solvent of the aqueous release coating solution is preferably 80% by weight of water based on the total weight of the coating solution, and 80% to 99% by weight of water and 1% by weight to ensure stability of the coating solution It is preferable to use a solvent mixed with ethylene glycol (cosolvent) in an amount of from 20% by weight to 20% by weight. As described above, the application layer according to an embodiment of the present invention can provide a release film that uses 80% by weight or more of water as a solvent and exhibits the same level as the appearance and adhesion of the organic solvent to the substrate. Due to this, the amount of VOC emission gas is small, and as an eco-friendly material, it can be used not only in the field of electronic and electrical materials but also in various uses such as for food.

In one embodiment, in order to impart antistatic properties, one more antistatic layer is formed on the application layer 20 or a conductive polymer resin is further included as an antistatic agent in the aqueous release coating solution for forming the application layer 20. can The conductive polymer resin is preferably an aqueous dispersion containing polyanions and polythiophene or an aqueous dispersion containing polyanions and polythiophene derivatives. The polyanion is an acidic polymer, and is a high molecular weight carboxylic acid, high molecular weight sulfonic acid, polyvinylsulfonic acid, or the like. Examples of the polymeric carboxylic acid include polyacrylic acid, polymethacrylic acid, and polymaleic acid, and examples of the polymeric sulfonic acid include polystyrenesulfonic acid, but is not limited thereto. In an embodiment of the present invention, a conductive polymer PEDOT aqueous solution was used as the conductive polymer resin.

In this case, the conductive polymer resin may be able to exhibit stable antistatic performance by using an aqueous dispersion having an average particle size of 10 to 90 nm. When the average particle diameter of the conductive polymer resin exceeds 90 nm, it is not uniformly distributed inside the coating layer, so the variation in surface resistance becomes very large, making it impossible to properly implement antistatic performance. As the particle size decreases, the intermolecular distance becomes greater than a certain distance, so that the antistatic performance cannot be realized.

In addition, the water-based release coating liquid forming the coating layer 20 may be heat-cured at a drying temperature of 130°C to 280°C to form an excellent coating layer, and more preferably have a drying temperature of 130°C to 150°C. The effect is even greater in offline processing.

In one embodiment, the coating thickness of the application layer 20 is preferably 0.01 to 2.0 ㎛ in dry thickness. If the coating thickness of the coating layer is less than 0.01 μm, the effect of reducing the peeling force is insignificant and there is a problem that the peeling force at a low speed is increased.

In addition, it is more preferable that the thickness of the coating layer after drying is 0.5 μm to 1.0 μm. When the thickness after drying is less than 0.5 μm, it is difficult to implement cemented carbide peeling, and when it exceeds 1.0 μm, there is a problem in that blocking occurs.

The coating method of the coating liquid forming the coating layer 20 is not particularly limited, and bar coating, gravure coating, comma coating or die coating may be applied. The water-based release coating solution applied in the liquid phase can be cured by heating in a hot air dryer at a temperature of about 150° C. for about 30 seconds to obtain a cured release region and an anchor region.

In one embodiment, the cemented carbide release film is aged at 60 ℃, 90% RH for 1 day, and then the high temperature peel strength and the room temperature peel strength after aging at room temperature for 1 day is preferably 15 gf / in or less, respectively.

In one embodiment, the cemented carbide release film is aged for 1 day at 60 ℃, 90% RH, it is preferable that the difference between the high temperature peel strength and the room temperature peel strength after aging for 1 day at room temperature is less than 10%.

In one embodiment, the cemented carbide release film preferably has a residual adhesive rate of 90% or more.

In one embodiment, the cemented carbide release film is preferably washed back and forth three times with a sulcus submerged in isopropyl alcohol (IPA), and then the coating layer is not peeled off.

Hereinafter, the configuration of the present invention and its effects will be described in more detail through Examples and Comparative Examples. However, these examples are for explaining the present invention in more detail, and the scope of the present invention is not limited to these examples.

[Example]

[Example 1]

1. Base film

A polyethylene terephthalate film having a thickness of 50 μm (manufacturer: Toray Advanced Materials, product name: XD500) was used as the base film.

2. Coating layer

Silicone emulsion resin composed of vinyl polysiloxane emulsion and hydrogen polysiloxane emulsion (manufacturer: Dow Chemical, product name: SYL-OFF 7920, vinyl siloxane 100 parts by weight: hydrogen polysiloxane 140 parts by weight) 5 parts by weight, platinum catalyst (manufacturer: Dow) Chemical, product name: SYL-OFF 7924) 0.5 parts by weight, polyester binder resin (manufacturer: Base Korea, product name: EW-210S ) 10 parts by weight, oxazoline group-containing resin (manufacturer: Japan Catalyst, product name: WS-700) 0.1 parts by weight of a surfactant (manufacturer: BYK, product name: BYK348) 0.1 parts by weight of an aqueous release coating solution containing 95 parts by weight of water and 4 parts by weight of ethylene glycol is applied to the base film using a bar coater, and then in a hot air dryer. A release film was prepared by heat curing at 140° C. for 30 seconds to form an application layer having a dry thickness of 0.5 μm.

[Example 2]

A release film was prepared in the same manner as in Example 1, except that 20 parts by weight of the silicone emulsion resin content and 2 parts by weight of the platinum catalyst content were used in the aqueous release coating solution, and the dry thickness was applied to 1 μm.

[Example 3]

A release film was prepared in the same manner as in Example 1, except that 20 parts by weight of a conductive polymer PEDOT aqueous solution (manufacturer: Heraeus: Clevious PT) was applied to the aqueous release coating solution.

[Comparative Example 1]

5 parts by weight of silicone emulsion resin (manufacturer: Dow Chemical, product name: SYL-OFF 7920) consisting of vinyl silicone emulsion and hydrogen polysiloxane emulsion, 0.5 parts by weight of platinum catalyst (manufacturer: Dow Chemical, product name: SYL-OFF 7924), A release film was prepared in the same manner as in Example 1, except that an aqueous release coating solution containing 0.1 parts by weight of a surfactant (manufacturer: BYK, product name: BYK348) and 95 parts by weight of water and 4 parts by weight of ethylene glycol was used. .

[Comparative Example 2]

A release film was prepared in the same manner as in Comparative Example 1, except that 5 parts by weight of the polyester resin was further included in the aqueous release coating solution.

[Comparative Example 3]

A release film was prepared in the same manner as in Comparative Example 1, except that 1 part by weight of a silane coupling agent (manufacturer: Dow Chemical, product name: Z-6043) was further included in the aqueous release coating solution.

[Comparative Example 4]

A release film was prepared in the same manner as in Comparative Example 1, except that 10 parts by weight of a urethane binder (manufacturer: ARAKAWA, product name: UREARNO W321) was further included in the aqueous release coating solution.

[Comparative Example 5]

A release film was prepared in the same manner as in Comparative Example 1, except that the dry thickness was 1 μm.

Physical properties were measured through the following experimental examples using the release films according to Examples 1 to 3 and Comparative Examples 1 to 5, and the results are shown in Table 1 below.

[Experimental example]

1. Solvent resistance

After wiping the release film three times with a sulcus (a thin cloth with large surface roughness) immersed in isopropyl alcohol (IPA), it was confirmed whether the coating layer fell off or not, and the following criteria were evaluated.

○: Good solvent resistance (no drop-off of coating layer)

△: Insufficient solvent resistance (partial damage to the coating layer)

X: No solvent resistance (most of the coating layer is damaged)

2. Appearance

The following criteria were evaluated according to the condition of the coated A4 size release film, such as mottled spots and stains.

○: Clean appearance without moss or stains

△: Partial moss and mottled spots (10 or less in A4 size) occurred

X: Poor wettability and poor coating appearance

3. Adhesion to the substrate

The release coating layer was evaluated by the following criteria according to the degree of peeling of the release coating layer by hand reciprocating 10 times (Rubbing TEST).

○: The release coating layer does not peel off

△: part of the release coating layer is peeled off

X: A lot of the release coating layer is peeled off

4. High temperature substrate adhesion

After aging the prepared release film in a thermo-hygrostat at 60° C. and 90% RH for 1 day, the release coating layer was rubbed by hand reciprocally 10 times, and the degree of peeling of the release coating layer was evaluated according to the following criteria.

○: The release coating layer does not peel off

△: part of the release coating layer is peeled off

X: A lot of the release coating layer is peeled off

5. Room temperature peel force

The peel strength of the release films according to Examples and Comparative Examples was evaluated using TESA7475 tape, which is a standard tape widely used in the industry.

First, the tape was attached to the release coating surface of the release area with a 2 kg roller and aged at room temperature for 1 day, and then the peel force at the time of peeling was measured. is measured, but the peeling rate is 0.3mpm and the unit is gf/in.

6. High temperature peeling force

After aging the prepared release film in a thermo-hygrostat at 60° C. and 90% RH for 1 day, after rubbing test, peel strength was measured in the same manner as in Experimental Example 5 above.

7. Check the peel force difference

The difference between the normal temperature peel force and the high temperature peel force measured in Experimental Examples 5 and 6 above was calculated by Equation 1 below as the peel force difference.

(Equation 1)

Peel force difference (%) = (High temperature peel force - Room temperature peel force) / High temperature peel force * 100 (%)

8. Residual Adhesion Measurement

After the release-coated sample for measurement was stored at 25° C. and 65% RH for 24 hours, a standard adhesive tape (Nitto 31B) was attached to the release-coated surface, and the sample was ^{pressed at room temperature under a load of 20 g/cm 2} for 24 hours. After collecting the tape adhered to the release coating surface without contamination, it was adhered to the flat and clean PET film surface, and then reciprocally compressed once with a 2 kg tape roller (ASTMD-1000-55T). The peeling force was measured as follows, and the residual adhesion rate was calculated by Equation (2).

Measuring instrument: chem-[0149] instrument AR-1000

Measurement method: 180° peel angle, peel speed 0.3 m/min

(Equation 2)

Residual adhesive rate (%) = [Peel force of the adhesive tape that was attached to the coated surface and peeled off / Peel force of the adhesive tape not in contact with the coated surface] X 100 (%)

9. Antistatic properties

After installing the sample in an environment of temperature 23°C and humidity 50%RH using an antistatic measuring device (Mitsubishi Co., Ltd.; model name: MCP-T600), the surface resistance was measured according to JIS K7194 standard.

solvent resistance Exterior write
adhesion high temperature material
adhesion room temperature peeling power
(gf/in) high temperature peeling power
(gf/in) peel force difference
(%) residual
Adhesion (%) surface resistance
(Ω/sq) Example 1 ○ ○ ○ ○ 12.1 12.4 2.4 91 8.1x10 ¹² Example 2 ○ ○ ○ ○ 5.0 5.5 9.1 90 1.7x10 ¹² Example 3 ○ ○ ○ ○ 13.4 13.9 3.6 92 2.6x10 ⁶ Comparative Example 1 X ○ X X 14.1 28.4 50.4 89 1.8x10 ¹² Comparative Example 2 △ ○ ○ X 16.7 29.6 43.6 91 3.4x10 ¹² Comparative Example 3 △ △ ○ △ 11.2 21.9 48.9 82 5.1x10 ¹² Comparative Example 4 ○ ○ ○ △ 16.4 23.5 30.2 61 5.9x10 ¹² Comparative Example 5 X ○ ○ X 5.4 35.7 84.9 88 6.3x10 ¹²

As can be seen from Table 1, the release film according to Example 1 of the present invention has excellent solvent resistance, adhesion to the substrate at room temperature and high temperature, and the difference between room temperature peel strength and high temperature peel strength is 2.4%, so that the change with time even under high temperature and high humidity conditions can be seen to be excellent. In addition, it can be seen that the release film according to Example 2 has excellent stability over time under high temperature and high humidity conditions even though the dry thickness of the coating layer is 1 μm to realize carbide peeling. In particular, it can be confirmed that the release film according to Example 3 including the antistatic agent can obtain a release film having excellent surface resistance while having excellent other physical properties.

On the other hand, it can be seen that the conventional release film of Comparative Example 1 has poor solvent resistance and poor adhesion to substrate and substrate at high temperature. It can be seen that the stability over time is significantly lowered under the conditions.

In addition, it can be seen that the release film of Comparative Example 2 has poor solvent resistance and poor adhesion to the substrate at high temperatures when only the polyester binder resin is used without an oxazoline group.

In addition, it can be seen that the release film of Comparative Example 3 shows significantly lower physical properties than the release films according to Examples 1 to 3 of the present invention, despite the addition of a silane coupling agent, which is typically used as a method of improving substrate adhesion and solvent resistance. can

In addition, it can be seen that the release film of Comparative Example 4 had insufficient silicone curing due to catalyst poison when the urethane binder was used, so that the residual adhesion rate was significantly reduced.

In addition, it can be seen that the release film of Comparative Example 5 has poor adhesion to the substrate at high temperature and remarkably deteriorates solvent resistance even when only the thickness of the coating layer is thickened for realization of carbide peeling.

As described above, the release film according to an embodiment of the present invention is basically excellent in solvent resistance and adhesion to the substrate, as well as excellent stability over high temperature, so there is little change even under high temperature and humidity conditions of 60°C and 90%RH. Therefore, it is easy to implement cemented carbide peeling.

In addition, when only the coating thickness is improved to implement light carbide peeling, the adhesion between the thick coating layer and the substrate is insufficient, and therefore, the peeling force is increased under high temperature and high humidity conditions, which may lead to a process accident, but according to an embodiment of the present invention It can be seen that the release film has excellent stability over time in high temperature and high humidity conditions even if the dry thickness of the coating layer is thickened to realize light carbide peeling.

In addition, the release film according to an embodiment of the present invention provides a release film that uses 80% by weight or more of water as a solvent and exhibits the same level as the appearance and adhesion of the organic solvent to the substrate, thereby providing an eco-friendly material with a small amount of VOC emission. It can be seen that it can be used not only in the field of electronic and electrical materials, but also in various applications such as food, and it can be seen that it is suitable for solving problems such as dust or contamination that may occur during the process by having antistatic properties.

In this specification, only a few examples among the various embodiments performed by the present inventors are described, but the technical spirit of the present invention is not limited or limited thereto, and it is of course that it may be modified and variously implemented by those skilled in the art.

10: description
20: coating layer
21: anchor area
22: release area
100: cemented carbide release film

Claims (14)

description and
As a release film comprising an application layer located on at least one surface of the substrate,
The application layer is made of a water-based release coating liquid, and includes an anchor region and a release region,
The water-based release coating solution includes vinyl polysiloxane, hydrogen polysiloxane, polyester resin, oxazoline group-containing resin, platinum catalyst, surfactant and solvent,
A cemented carbide release film comprising 0.1 to 10 parts by weight of the oxazoline group-containing resin relative to 100 parts by weight of the polyester resin, and 110 to 200 parts by weight of the hydrogen polysiloxane based on 100 parts by weight of the vinylpolysiloxane. delete According to claim 1,
The anchor region is formed of a polyester resin and an oxazoline group-containing resin, a cemented carbide release film. delete According to claim 1,
The release region is formed of a vinyl polysiloxane and a hydrogen polysiloxane, a cemented carbide release film. delete According to claim 1,
The solvent is 80% by weight to 99% by weight of water and 1% to 20% by weight of ethylene glycol, a carbide release film comprising a. According to claim 1,
The water-based release coating liquid further comprises an antistatic agent, a light release film. According to claim 1,
After drying of the coating layer, the thickness is 0.01 to 2.0 μm, a cemented carbide release film. 10. The method of claim 9,
After drying of the coating layer, the thickness is 0.5 to 1.0 μm, a cemented carbide release film. 11. The method of any one of claims 1, 3, 5, 7 to 10,
The cemented carbide release film is aged at 60 ℃, 90% RH for 1 day, and then aged at room temperature for 1 day and high temperature peel strength is 15 gf / in or less, respectively, the cemented carbide release release film. 12. The method of claim 11,
The cemented carbide release film is aged at 60 ℃, 90% RH for 1 day, the difference between the high temperature peeling force and the room temperature peeling force after aging for 1 day at room temperature is less than 10%, the carbide peeling release film. 11. The method of any one of claims 1, 3, 5, 7 to 10,
The cemented carbide release release film has a residual adhesive rate of 90% or more, a cemented carbide release release film. 11. The method of any one of claims 1, 3, 5, 7 to 10,
The cemented carbide peeling release film is a carbide peeling release film that does not peel off after wiping it back and forth 3 times with a sconce immersed in isopropyl alcohol (IPA).

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