JPH10323944A - Release film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a film having stable dry peeling strength, good peeling properties in a high-speed zone, and good transparency with lower cost and without generating paper powder by providing a case composed of solventless silicone on a resin film by a specific amount per unit area. SOLUTION: A resin film is preferably a film having good dimensional stability to heat, by considering curing after transferring solventless silicone, or heat applied to a finished release film at the time of post-treatment such as tack treatment. A solventless silicone case requires 0.05-0.5 g/m<2> amount. If the amount of the solventless silicone case is less than 0.05 g/m<2> , stable dry peeling properties can not be obtained, and high-speed peeling properties are not improved. If the amount of the solventless silicone case is over 0.5 g/m<2> , blocking is generated on the finished release film, which inhibits the next process, or causes breaking of the release film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a release film. More specifically, a cured layer of solventless silicone is provided on a resin film in an amount of 0.05 to 0.5 g / m ² , which has good high-speed peeling properties, no silicone backside transfer, and further blocking. It relates to a significantly improved release film.

[0002]

2. Description of the Related Art Generally, a seal having an adhesive layer, a tape, a sticker, a display label, and a transfer foil (hereinafter, referred to as a display) for transferring various designs are provided on a support having a release function (hereinafter, release). Film). In other words, papers, plastic sheets, plastic films, and the like provided with an adhesive function and a transfer function have a release function on a surface having an adhesive or a surface having a transfer in order to protect those functions. A release film is laminated.

In recent years, these release films have been required to have a function of lowering peel resistance in a higher-speed peeling region as a function. In other words, when applying a display label or the like with an auto labeler, if the peeling strength at high speed is high, label feeding mistakes frequently occur and the production line must be stopped, so the peeling film has a low peeling resistance in a high speed peeling region. Is required.

Generally, these release films are made of paper,
It is made of a plastic sheet or plastic film, and is directly laminated on the adhesive surface of the display or the back surface of the transfer foil.
The release function of the release film to facilitate release from the adhesive surface of the display body and the back of the transfer foil is performed by releasing the surface of papers, plastic sheets, and plastic films. It is provided by forming a surface.

Conventionally, as a method of releasing a surface of a plastic sheet or a plastic film, a method of treating the surface of the sheet or the film with a release agent has been used.

As the release treatment agent, those having a silicone resin as a main component and those having a fluorine resin as a main component are known. Among them, generally, a solvent-type silicone mainly containing a silicone resin diluted with various organic solvents is mainly used as a mold release agent.

However, a solvent-type silicone alone has a high peel strength in a high-speed range, and causes a problem such as a decrease in productivity when applied with an auto-labeler or the like. , A silicone resin oligomer is added.

Although the above method can certainly lower the peel strength in the high-speed range, after the release surface is formed, the added silicone resin oligomer bleeds. This causes a problem such as transfer to the back of the display. As a result, the printed surface of the display body is contaminated, and printing is frequently performed, which is not preferable because the commercial value is impaired.

On the other hand, there has been proposed a method of using solventless silicone instead of solvent silicone. The solvent-free silicone is characterized in that the properties in normal peeling are the same as those of the solvent-based silicone, and it is excellent in productivity without requiring removal and recovery of the solvent.

However, when a release film is formed using the solventless silicone, if the release film is formed in the same manner as the conventional solvent-type silicone, the release film transferred with the silicone is blocked, and the production is difficult. There is a drawback that the properties are significantly reduced.

Further, there is another problem that unevenness is generated in the transferred silicone coating, thereby causing the silicone coating to break. If the silicone film is cracked, stable peeling properties in normal state cannot be found, and the peeling properties in a high-speed region cannot be improved.

In other words, when transferring solventless silicone onto a smooth surface such as a resin film, it is difficult to control the amount of solventless silicone transferred by a conventional transfer method. It was extremely difficult to stably transfer silicone at a transfer amount of 1.0 g / m ² or less. As a result, since the solvent-free silicone is transferred in an amount of 1.0 g / m ² or more while generating unevenness, it causes blocking, and peeling properties in a high-speed region are not improved, so that the silicone resin is practically used. Is an obstacle in

In recent years, a multi-roll system has been proposed as a transfer method for thin film transfer. However, the above-mentioned problem of the transfer amount cannot be solved for a resin film having a smooth surface.

Therefore, even when the above-described multi-roll transfer method is used, the solvent-free silicone cannot be transferred thinly, and the finished release film causes blocking, which has not solved the problem.

Further, since the release film is required to be used in an aseptic room for food or the like, or in a clean room during an electronic material manufacturing process, paper release film generates paper dust. Cause contamination of the clean room,
There is a problem that it may cause a reading error of a printed bar code or the like.In such a field, a release film made of paper cannot be used. In order to detect with a phototube with high accuracy, it is required to make the release film transparent. Furthermore, such a release film is discarded after the display body is attached to the adherend, and is required to be a material that can be easily recovered and reused from the viewpoint of nature protection and resource recycling. .

[0016]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to have a stable normal peel strength, a good peeling property in a high speed range, a low cost, no generation of paper dust, and a good transparency. To provide a release film that is
An object of the present invention is to provide a stable production method in which a finished release film does not block.

[0017]

SUMMARY OF THE INVENTION In view of the above-mentioned problems of the prior art, the release characteristics in a high-speed range are improved, no paper dust is generated, the transparency is good and the cost is low. The release film which the release film does not block was studied diligently.

As a result, surprisingly, by providing a solventless silicone cured layer thinly and uniformly in a specific amount on the resin film, the subject matter, especially the peeling property in the high speed range, is extremely effectively improved. This led to the present invention.

That is, the present invention is a release film comprising a solvent-free silicone cured layer provided on a resin film in an amount of 0.05 to 0.5 g / m ^2.
When the solvent-free silicone containing the curing catalyst in the range of 0.5 g / m ² is transferred to the resin film by the roll transfer method, the amount of the transfer is set to 0.
A method for producing a release film, which is controlled in a range of from 0.5 to 0.5 g / m ² , and a method for producing a release film, wherein a solvent-free silicone containing a curing catalyst is transferred to a resin film and then homogenized using a smoother roll. It is.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The solvent-free silicone used in the present invention is not limited to any known one. For example, generally commercially available silicones can be used. A mixture of a siloxane oligomer and a vinyl group-containing polydimethylsiloxane is preferably used.

Preferably, a curing catalyst is added to the solventless silicone. As the curing catalyst, any catalyst can be used as long as it can thermally cure the solventless silicone. Among them, a platinum group curing catalyst is preferably used.

Further, there is no problem even if a reaction modifier, a reaction inhibitor and the like are added to the solventless silicone used in the present invention as long as the effects of the present invention are not impaired.

In the present invention, the viscosity of the solventless silicone is preferably 1c. p. s. ~ 10000c. p.
s, and more preferably 10c. p. s. ~
1000c. p. s. Is used. Viscosity is 10
000c. p. s. If the amount is larger, it is not preferable because a stable transfer amount cannot be obtained. 1c. p. s. If it is less than
It is not preferable because the solventless silicone is immediately scattered and transfer defects occur.

As the resin film used in the present invention, known films can be used without any limitation.
Nylon resin film, polyester resin film, polyethylene resin film, polystyrene resin film,
Examples include a polypropylene resin film. Among them, a polypropylene resin film is preferable. The polypropylene resin film is a film made of a polypropylene resin, and is particularly preferably a film made of a crystalline polypropylene resin. The crystalline polypropylene resin generally has stereoregularity and can be used without any limitation, whether it is isotactically controlled or syndiotactically controlled.

As the polypropylene resin, known ones can be used without limitation, and a propylene homopolymer, a random copolymer or block copolymer of propylene with one or more other α-olefins, or a mixture of these polymers is used. Can do things. Examples of the α-olefin include ethylene, 1-butene, 1-pentene, 1-hexene, and 1-hexene.
Heptene, 1-octene, 1-nonene, 1-decene, 4
-Methyl-1-pentene, 3-methyl-1-butene and the like. Furthermore, these α-olefin homopolymers or copolymers of α-olefins may be used in combination with a polypropylene resin. In addition, as a method for producing the polypropylene resin, a known method is employed, for example, a method of polymerizing using a Ziegler-Natta catalyst or a metallocene catalyst.

The resin film used in the present invention may be any resin film produced by any production method without any particular limitation. For example, a T-die cast film, a uniaxially stretched film, a biaxially stretched film, an inflation film, etc. Can be used without restrictions. In addition, a commercially available resin film can be used without any particular limitation.

The resin film used in the present invention may be a single-layer film or a multilayer film. As a method for producing a multilayer film, an extrusion lamination method, a coextrusion method, a dry lamination method and the like are generally employed.

The surface on which the solvent-free silicone cured layer of the resin film used in the present invention is provided has a surface wetting index of 3
It is preferably at least 5 mN / m from the viewpoint of adhesion between the resin film after curing of the solventless silicone and the cured silicone layer. The method for setting the surface wetting index of the surface of the resin film to the above value may be any known method without limitation.For example, in the case of a polypropylene resin film having a small surface wetting index, by performing a surface treatment such as corona treatment. Can be achieved.

The resin film used in the present invention may contain any anti-blocking agent. Rather, from the viewpoint of blocking prevention, it may be positively compounded, but it goes without saying that the technical problem of the present invention cannot be solved only by the blocking inhibitor. When the resin film has a multilayer structure, an antistatic agent may be blended in a layer opposite to the surface layer on which the silicone cured layer is provided.

The resin film used in the present invention has a high heat resistance in consideration of the heat applied during curing after transferring the solvent-free silicone or during post-processing such as adhesive processing performed on the finished release film. It is preferable that the film has good dimensional stability. As an index of heat resistance dimensional stability, a load of 5 kg / m was applied in the MD direction, and 12
It is preferable that the shrinkage in the TD direction is less than 5% when left at 0 ° C. for 10 minutes.

The thickness of the resin film used in the present invention is preferably from 10 to 200 μm,
0 μm is a more preferable range. Film thickness is 10μ
When it is less than m, when transferring solventless silicone onto a resin film, the resin film is wrinkled and disadvantageously impairs product quality, which is not preferable. Further, if the film thickness exceeds 200 μm, the transparency of the resin film deteriorates, which is not preferable.

In the release film of the present invention, the amount of the solvent-free silicone cured layer must be 0.05 to 0.5 g / m ² . When the amount of the solvent-free silicone cured layer is less than 0.05 g / m ² , a stable normal peeling force cannot be obtained, and further, an effect of improving a high-speed peeling force cannot be found, which is not preferable. On the other hand, when the amount of the solvent-free silicone cured layer exceeds 0.5 g / m ² , blocking occurs in the finished release film, which hinders the next step or causes tearing of the release film, which is not preferable. .
Further, it is not preferable because a synergistic peeling property in a high-speed region due to uniform transfer cannot be obtained.

In the release film of the present invention, the solvent-free silicone cured layer is preferably provided uniformly on the resin film. If the solvent-free silicone cured layer is not uniform, that is, if there is a visual defect of the silicone cured layer, it is not preferable because the peeling properties of the silicone in normal state and the peeling properties in a high-speed range are not stable, and furthermore, it is caused by the peeling of the silicone. This is not preferable because the appearance of the film becomes poor and the commercial value of the release film is reduced.

In the present invention, the method of transferring the solventless silicone to the resin film is performed by a general roll transfer method. Examples of the roll transfer method used in the present invention include a method using a coating roll such as a gravure coater, a gravure reverse coater, an offset coater, a four-stage reverse coater, and a five-roll coater.

The following method can be mentioned as a preferable method for controlling the transfer amount of the solvent-free silicone to 0.05 to 0.5 g / m ² by the above-mentioned roll transfer method. That is, in the transfer by the roll transfer method, the amount of the solventless silicone on the coating roll is adjusted by a blade immediately before being transferred to the film, and the transfer amount transferred to the film is adjusted. The method of transferring solventless silicone from a coating roll equipped with a blade enables stable transfer of solventless silicone onto a resin film at a transfer rate of 0.05 to 0.5 g / m ^2. Become.

The blade may be made of any material as long as the effect of the present invention is not impaired.
Specific examples of the blade material include a plastic material such as polyester and a metal material obtained by applying hard chrome plating to stainless steel. The width of the blade is preferably at least equal to or greater than the width of the resin film to be transferred, and is generally equal to or greater than the width of the coating roll, and is preferably a width that can contact the entire coating roll. . The shape of the blade may be any shape as long as the effects of the present invention are not impaired.

In the present invention, in consideration of prevention of unevenness of the solventless silicone cured layer, it is preferable to transfer the solventless silicone to the resin film and then to further uniform the transfer surface.

The following method can be mentioned as a preferable method for making the above-mentioned transfer surface uniform. That is, after transferring the solventless silicone to the resin film by a roll transfer method or the like, the transfer surface is smoothed again by the smoother roll on the solventless silicone transferred onto the resin film. In the uniforming process using the smoother roll, transfer unevenness and transfer defects of the solventless silicone on the resin film are further improved, so that extremely stable release characteristics can be obtained.

The smoother roll can be made of rubber or metal without any problem as long as the effect of the present invention is not impaired. For example, silicone rubber, styrene-butadiene rubber, nitrile-butadiene rubber, or the like is generally used as a rubber base material, and hard chrome-plated stainless steel is typically used as a metal base material. Above all, considering that the substrate to be transferred is a resin film, a rubber roll which is less likely to damage the surface of the film is preferable.

The shape of the surface of the smoother roll may be either solid or grooved, as long as the effect of the present invention is not impaired.

The direction of rotation of the smoother roll is as follows:
It does not matter whether the resin film rotates forward or backward in the running direction as long as the effects of the present invention are not hindered. Further, an oscillation device may be attached to the smoother roll.

In the release film of the present invention, the solvent-free silicone is cured by transferring the above-mentioned solvent-free silicone to a resin film and then applying heat to cure the solvent-free silicone. The conditions for curing the solventless silicone can be any known method.
Generally, the oven temperature should be 2 to 70 ° C to 180 ° C.
A method of curing in a range of 60 seconds to form a silicone film is employed.

[0043]

The release film of the present invention exhibits a stable normal release force, has improved high-speed release characteristics, does not generate paper dust, has good transparency, and has no inspection errors with a photoelectric tube. It is an inexpensive film. Further, the release film described above can be suitably manufactured by the manufacturing method of the present invention.

[0044]

Hereinafter, the present invention will be described with reference to examples.
The present invention is not limited to these.

(Evaluation of Physical Properties) [Amount of Solvent-Free Silicone Transfer] A resin film to which the solvent-free silicone was transferred was coated with a fluorescent X-ray (L) manufactured by Oxford.
ab-X3000) to quantify the amount of silicon. The value obtained by subtracting the measured value of the film before transfer from the quantitative value was defined as the transfer amount.

[Normal Peeling Force] It was measured according to JIS K 6854.

[High-Speed Peeling Force] An adhesive (SK Dyne 801B) was coated on a release film by using a Meyer bar applicator to a thickness of 80 μm wet. After being applied in a thick thickness, it was dried at 80 ° C. for 5 minutes. Next, a 50 μm polyester film was adhered to the release film surface coated with the adhesive, and aged at 25 ° C. under a load of 20 g / cm ² for 48 hours. After aging, it was cut into 50 mm x 300 mm to obtain a test piece. This test piece was measured four times for each sample at a peeling speed of 50, 100, and 200 m / min using a high-speed peeling tester (TE-702 manufactured by Tester Sangyo Co., Ltd.), and the average value was taken as the high-speed peeling force.

[Silicon Tobi] A release film was cut to prepare a 100 mm × 100 mm test piece.

This test piece was visually inspected for the number of hits. Each sample was measured four times and the average value was taken. The number of hits was 0, "no", the number of hits was 1 to 10, "somewhat", the number of hits was 10 or more, "yes", Was evaluated.

[Blocking] The release treated surface of the release film and the specific treated surface of the release film were superimposed and pressed with a hydraulic press at 50 ° C. and 100 kg / cm ² for 16 hours. A test piece was created.

The test piece was measured for resistance to shear peeling using Tensilon. Each sample was measured four times, the average value was taken, and the resistance value was 5.0 g /
Blocking less than 4 cm is "No" and resistance value is 5.0 g
When / 4 cm or more and less than 10.0 g / 4 cm, blocking was evaluated as "slight", and when resistance was 10.0 g / 4 cm or more, blocking was evaluated as "present".

[Transparency] Measured according to JIS K 7105.

Example 1 (Preparation of Raw Material Resin) Melt Flow Rate 7.0 g / 10
100 parts by weight of crystalline homopolypropylene and 2,6-di-butylhydroxytoluene as an antioxidant with respect to 100 parts by weight of the crystalline homopolypropylene.
1 part by weight, calcium stearate as chlorine supplement:
The resin composition to which 0.1 part by weight was added was mixed and stirred with a Henschel mixer for 5 minutes, and then granulated at 230 ° C. using a 60 mmφ extrusion granulator to obtain a raw material pellet A.

(Preparation of Unstretched Film) Using the obtained raw material pellets A, an unstretched film was formed by the following method. Pellets A are supplied to an extruder having a screw diameter of 75 mmΦ and extruded from a T-die at a resin temperature of 230 ° C.
A monolayer film having a thickness of 60 μm was obtained through a cooling roll at 0 ° C. The surface wetting index of the surface to be subsequently subjected to the release treatment is 3
A non-stretched film was obtained by performing corona discharge treatment so as to have a pressure of 7 mN / m and then aging at 40 ° C for 24 hours. Hereinafter, this film is referred to as “film X”.
Call.

(Releasing Agent Treatment) Using the obtained “film X”, a releasing agent treatment was carried out by the following method.

Using a gravure reverse coater provided with a gravure roll (gravure mesh # 0) provided with a metal blade and a silicone rubber smoother roll provided on the transfer surface side after the transfer, the “film X” was prepared. The film was set so that the corona-treated surface became the transfer surface.

Solvent-free silicone as a release agent includes solvent-free silicone LTC1053L manufactured by Dow Corning Toray Silicone Co., Ltd .: 100 parts by weight and LTC11
A mixture obtained by uniformly mixing 00M: 10 parts by weight was used.

First, the solventless silicone was transferred to a gravure roll, and then the solventless silicone was scraped off with a metal blade to adjust the transfer amount, and then transferred onto the “film X”. Further, the transfer surface of the “film X” to which the solvent-free silicone was transferred was rotated in the forward direction of the film with a smoother roll to make it uniform.

The “film X” on which the solventless silicone was uniformly transferred was continuously transferred to an oven at 120 ° C.
By heat-treating for -15 seconds, a solvent-free silicone cured layer was formed, and a release film was obtained.

Table 1 shows the silicone transfer amount and physical properties of the release film of the obtained release film.

Example 2 (Preparation of Raw Material Resin) A raw material pellet A was prepared in the same manner as in Example 1, and a raw material pellet B was prepared by the following method.

Melt flow rate 7.0 g / 10 min
100 parts by weight of a crystalline homopolypropylene, 0.1 part by weight of 2,6-di-butylhydroxytoluene as an antioxidant, and 0.1 part by weight of calcium stearate as a chlorine scavenger based on 100 parts by weight of the crystalline homopolypropylene
A resin composition containing 1.0 parts by weight of silicone particles (trade name: Tospearl 120) as a blocking inhibitor was mixed and stirred with a Henschel mixer for 5 minutes, and then 230 ° C. using a 60 mmφ extrusion granulator. Granulated at
Raw material pellet B was used.

(Preparation of Unstretched Film) Using the obtained raw material pellets A and B, an unstretched film was formed by the following method.

Pellets A are supplied to a central layer main extruder having a screw diameter of 75 mmφ, and pellets A and B are supplied to two surface layer sub-extruders having a screw diameter of 50 mmφ, and extruded from a multi-manifold type T die at a resin temperature of 230 ° C. ,
Through a cooling roll at 30 ° C., a two-layer, two-layer coextruded film having an A / B configuration and an A layer of 48 μm and a B layer of 12 μm was obtained. Subsequently, a corona discharge treatment was performed so that the surface wettability index on the surface layer B side to be subsequently subjected to the mold release treatment was 37 mN / m, and then aging was performed at 40 ° C. for 24 hours to obtain a non-stretched film. Hereinafter, the film is referred to as “film Y”.

(Releasing Agent Treatment) Using the obtained “Film Y”, a releasing agent treatment was performed by the following method.

Using a gravure reverse coater provided with a gravure roll (gravure mesh # 0) provided with a metal blade and a silicone rubber smoother roll provided on the transfer surface side after the transfer, the “film X” was prepared. The film was set so that the corona-treated surface became the transfer surface.

Solvent-free silicone as a releasing agent includes solvent-free silicone LTC1053L manufactured by Dow Corning Toray Silicone Co., Ltd .: 100 parts by weight and LTC11
A mixture obtained by uniformly mixing 00M: 10 parts by weight was used.

First, the solvent-free silicone was transferred to a gravure roll, and then the solvent-free silicone was scraped off with a metal blade to adjust the transfer amount, and then transferred onto the “film Y”. Further, the transfer surface of the “film Y” to which the solvent-free silicone was transferred was rotated in the forward direction of the film by a smoother roll to make it uniform.

The “film Y” on which the solventless silicone was uniformly transferred was continuously transferred to an oven at 120 ° C.
By heat-treating for -15 seconds, a solvent-free silicone cured layer was formed, and a release film was obtained.

The silicone transfer amount and physical properties of the release film of the obtained release film are summarized in Table 1. Example 3 (Preparation of Raw Material Resin) Pellets A, as in Examples 1 and 2,
B was prepared, and a raw material pellet C was prepared by the following method.

Melt flow rate 7.0 g / 10 min
100 parts by weight of a crystalline homopolypropylene, 0.1 part by weight of 2,6-di-butylhydroxytoluene as an antioxidant, and 0.1 part by weight of calcium stearate as a chlorine scavenger based on 100 parts by weight of the crystalline homopolypropylene
A resin composition containing 0.4 parts by weight of stearic acid monoglyceride as an antistatic agent was mixed and stirred with a Henschel mixer for 5 minutes, and then granulated at 230 ° C. using a 60 mmφ extrusion granulator. Raw material pellet C.

(Preparation of Unstretched Film) Using the obtained raw material pellets A, B and C, an unstretched film was formed by the following method.

That is, the pellet A is supplied to the central layer main extruder having a screw diameter of 75 mmΦ, and the pellets B and C are supplied to two surface layer extruders having a screw diameter of 50 mmΦ. Through a cooling roll at 30 ° C., a three-layer, three-layer coextruded film having a B / A / C configuration and an A layer having a thickness of 36 μm and B and C layers each having a thickness of 12 μm was obtained. Subsequently, a corona discharge treatment is performed so that the surface wettability index of the surface layer B on which the release treatment is performed is 37 mN / m.
After aging for 4 hours, an unstretched film was obtained. Hereinafter, the film is referred to as “film Z”.

(Releasing Agent Treatment) Using the obtained “Film Z”, a releasing agent treatment was performed by the following method.

Using a gravure reverse coater provided with a gravure roll (gravure mesh # 0) provided with a metal blade and a silicone rubber smoother roll provided on the transfer surface side after the transfer, the “film X” was prepared. The film was set so that the corona-treated surface became the transfer surface.

Solvent-free silicone as a releasing agent includes solvent-free silicone LTC1053L manufactured by Dow Corning Toray Silicone Co., Ltd .: 100 parts by weight and LTC11
A mixture obtained by uniformly mixing 00M: 10 parts by weight was used.

First, the solventless silicone was transferred to a gravure roll, and then the solventless silicone was scraped off with a metal blade to adjust the transfer amount, and then transferred onto the “film Z”. Further, the transfer surface of the “film Z” to which the solvent-free silicone was transferred was rotated in the forward direction of the film with a smoother roll to make it uniform.

The “Film Z” on which the solventless silicone was uniformly transferred was continuously transferred to an oven at 120 ° C.
By heat-treating for -15 seconds, a solvent-free silicone cured layer was formed, and a release film was obtained.

The silicone transfer amount and physical properties of the release film of the obtained release film are summarized in Table 1. Example 4 "Film X" was used as a release agent, and was used as a releasing agent.
The same procedure as in Example 1 was performed except that 10 parts by weight of LTC1102L and 10 parts by weight of LTC1102L were used. The results are shown in Table 1.

Example 5 The same operation as in Example 1 was carried out except that the "film X" was used and the smoother roll made of silicone rubber was reversed in the direction of flow of the film to make it uniform. The results are summarized in Table 1.

Example 6 Example 1 was carried out in the same manner as in Example 1 except that the temperature of the cooling roll was changed to 60 ° C. to produce “film X”.

Example 7 When manufacturing “Film Z” of Example 3, B / A / C
The same procedure as in Example 1 was carried out except that the thickness of the layer structure was 80 μm for the layer A and 48 μm for the layer A, and 16 μm for the layers B and C.

Example 8 At the time of the release treatment of Example 1, the release treatment was performed without using a smoother roll for uniformity. The results are shown in Table 1.

Example 9 When manufacturing “Film Z” of Example 3, B / A / C
Was performed in the same manner as in Example 1 except that the thickness of the layer structure was 132 μm for the A layer, the thickness of the B layer and the C layer was 44 μm, and the multilayer film was 220 μm.

Comparative Example 1 At the time of the releasing treatment of Example 1, the releasing treatment was carried out without attaching a blade to the gravure roll. The results are shown in Table 1.

Comparative Example 2 Solvent-type silicone (manufactured by Dow Corning Toray Silicone Co., Ltd.) LTC was used for the release treatment in Example 1.
760A: 100 parts by weight, SRY212: 1 part by weight, S
D7200: 0.1 part by weight, and the same operation as in Example 1 was performed except that the mixture was diluted with 500 parts of a solvent having a volume ratio of toluene and hexane of 6/4, and subjected to a release treatment.
The results are shown in Table 1.

Comparative Example 3 At the time of the release treatment of Example 1, the blade was not mounted on the gravure roll, and the uniformity was not achieved with the smoother roll.
Release processing was performed. The results are shown in Table 1.

Comparative Example 4 The release treatment was carried out in the same manner as in Example 1 except that the transfer amount was adjusted to 0.03 g / m ² during the release treatment in Example 1. The results are shown in Table 1.

[0089]

[Table 1]

Claims (5)

[Claims] (1) a cured layer of a solventless silicone having a thickness of 0.05 to
A release film provided on a resin film in an amount of 0.5 g / m ² . 2. The release film according to claim 1, wherein the thickness of the resin film is 10 to 200 μm. 3. The release film according to claim 1, wherein the resin film is made of crystalline polypropylene. 4. The method according to claim 1, wherein when the solventless silicone is transferred to the resin film by a roll transfer method, the transfer amount is from 0.05 to 0.05.
A method for producing a release film, wherein the release film is controlled in a range of 0.5 g / m ² . 5. A method for producing a release film, comprising transferring a solvent-free silicone to a resin film by the method according to claim 4, and homogenizing the solvent-free silicone containing the transferred curing catalyst using a smoother roll. .