WO2006001151A1

WO2006001151A1 - Double side release film

Info

Publication number: WO2006001151A1
Application number: PCT/JP2005/009548
Authority: WO
Inventors: Ken Oono
Original assignee: Mitsubishi Polyester Film Corporation
Priority date: 2004-06-25
Filing date: 2005-05-25
Publication date: 2006-01-05
Also published as: JP2006007550A

Abstract

A double side release film which comprises a polyester film and silicone resin coatings formed on both surfaces of the polyester film, and satisfies the following formulae (1) to (6) at the same time: 0.01 ≤ Ra ≤ 0.15 (1) 0.04 ≤ Cw ≤ 0.5 (2) 0.7 ≤ Cw/Ra ≤ 15 (3) 1.0 ≤ FB/FA ≤ 4.0 (4) 10 ≤ FA + FB ≤ 100 (5) 85 ≤ Zs (6) [wherein Ra represents an arithmetic mean roughness (μm) of the polyester film, Cw represents the amount (g/m2) of the silicone resin coating applied, FA represents a releasing force (mN/cm) of a surface coated with a silicone resin exhibiting a weaker releasing force, FB represents a releasing force (mN/cm) of a surface coated with a silicone resin exhibiting a stronger releasing force, Zs represents a residual adhesion force percentage (%) of a surface coated with the silicone resin, defined in the specification].

Description

Specification

Double-sided release film

Technical field

[0001] The present invention relates to a double-sided release film. Specifically, the present invention relates to a double-sided release polyester film that can be suitably used, for example, when producing a double-sided pressure-sensitive adhesive sheet.

Background art

[0002] Polyester films represented by polyethylene terephthalate are excellent in mechanical strength, dimensional stability, flatness, heat resistance, chemical resistance, optical properties, etc., and in cost performance. It is used as a film. An example of its use is a release film used in various adhesive sheet manufacturing processes.

[0003] For example, on the back side of a plasma display, a heat-dissipating sheet that is interposed between an aluminum chassis and a light-emitting glass body and has adhesive surfaces on both surfaces to fix the aluminum chassis and the glass body is, for example, Manufactured by the manufacturing process as in (1) to (2).

[0004] (1) An acrylic resin pressure-sensitive adhesive solution to which inorganic particles or the like are appropriately added is applied to the release surface of the release film and dried. If necessary, an adhesive primer layer for the silicone resin heat dissipation layer is further provided. It is applied and dried, and the film with the adhesive layer is wound up into a roll. At this time, in order to prevent the adhesive film from sticking to the back side of the adhesive film, a release cover film is laminated on the adhesive surface before scraping, and the release film Z adhesive layer Z ( The laminated film having a layer structure of (adhesive primer layer) / release film is wound up in a roll shape.

[0005] (2) While peeling off the release film on the primer layer side of the obtained laminated film, a heat dissipation layer forming resin solution composed of silicone resin, inorganic particles, foaming agent, etc. is applied to one surface of the primer. Similarly, the laminated film obtained in the same step (1) is similarly unwound from another unrolled portion, laminated on the laminated sheet body having the former heat dissipation layer, and the release film / adhesive layer / ( Adhesive heat-dissipating sheet with release films on the front and back, like adhesive primer layer) / heat-dissipating silicone resin layer / (adhesive primer layer) / adhesive layer / release film Manufacture the body.

[0006] When using the heat-dissipating sheet body, the release film is peeled off one side at a time, and adhesive layer Z (adhesive primer layer) / heat-dissipating silicone resin layer Z (adhesive primer layer) Z adhesive A double-sided pressure-sensitive adhesive having a layer structure is used as a heat-dissipating sheet with an adhesive fixing function.

[0007] In the processing steps (1) to (2), it is necessary to use both a single-sided release film as a base film and a single-sided release cover film for preventing backside adhesion.

[0008] In order to reduce costs, a processing method using a double-sided release film (or release paper) that does not use a cover film is known (see, for example, Patent Documents 1 to 5). However, in the industrialization, a simple double-sided release film causes various defects due to its characteristics, and improvement is desired. The double-sided PSA sheet is used not only for the above-mentioned applications but also for various industrial applications. However, when a double-sided release film is used for these, the same problem occurs and the characteristics need to be improved. .

Patent Document 1: Japanese Patent Laid-Open No. 2001-348542

Patent Document 2: JP-A-9 141811

Patent Document 3: Japanese Patent Laid-Open No. 9-156018

Patent Document 4: JP-A-9-262937

Patent Document 5: JP-A-11-302606

Disclosure of the invention

Problems to be solved by the invention

[0010] The present invention has been made in view of the above circumstances, and its object is to provide a double-sided adhesive sheet that can be suitably used in the production of a double-sided pressure-sensitive adhesive sheet that has improved the following problems (1) to (5). It is to provide a release film.

[0011] (1) Troubles in the rolling characteristics (slipperiness) of the film during the production or use of a double-sided release film.

(2) Broking and transition 'bloom phenomenon of the silicone coating layer of the double-sided release film.

(3) Trouble with release of double-sided release film.

(4) Release property An adhesive layer is applied to one side of a double-sided release film having A side and release side B. Releasability A surface Z adhesive resin layer Z releasability Rolled with cloth and wound, rolls with an interfacial structure may not peel off at the intended releasability A surface during unwinding Removability Troubles caused by transfer problems that peel off from the interface with the B surface, or the adhesive layer floating from the release film.

(5) Trouble of lowering adhesive strength due to transfer of release component from release film when using double-sided PSA sheet.

Means for solving the problem

[0012] In order to solve the above-mentioned problems, the present inventors have intensively studied. As a result, they have found that the above-mentioned problems can be easily solved by a release film having a specific configuration, and have completed the present invention. .

[0013] A first aspect of the present invention is a double-sided release film comprising a polyester film and a silicone resin coating film formed on both sides of the polyester film, wherein the following formulas (1) to (6) are simultaneously given: It exists in the double-sided release film characterized by satisfying.

[0014] 刚

0. 01≤R a≤0. 15 (1)

0. 04≤Cw≤ 0.5 (2)

0. 7≤Cw / R a≤ 15 (3)

1. 0≤FB / FA≤4.0 (4)

10≤FA + FB≤ 100 (5)

85≤Z s (6)

[0015] In the above formula, Ra is the arithmetic average roughness of the polyester film surface (μm), Cw is the coating amount of the silicone resin coating (g / m ² ), and FA is the silicone resin having the light release force The peel force on the paint film surface (mNZcm), FB represents the peel force (mN / cm) on the silicone resin paint film surface with the heavy peel force, and Zs represents the residual adhesion rate (%) on the silicone resin paint film surface.

The invention's effect

[0016] The double-sided release film of the present invention has the conventional problems of film squeezing characteristics (slidability), silicone coating layer blocking, transition. Bloom phenomenon, release failure trouble, transfer trouble, release trouble. Trouble of floating adhesive layer from mold film, trouble of lowering adhesive strength, etc. have been improved and it has practicality, and its industrial value is high.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. However, the description of the constituent elements described below is a representative example of embodiments of the present invention, and the present invention is not limited to these contents. The polyester used in the present invention is obtained, for example, by polycondensation of an aromatic dicarboxylic acid and an aliphatic glycol. Examples of the aromatic dicarboxylic acid include terephthalenolic acid and 2,6-naphthalenedicarboxylic acid, and examples of the aliphatic glycol include ethylene glycol, diethylene glycol, and 1,4-cyclohexanedimethanol. A typical example of the polyester is polyethylene terephthalate (PET). The polyester may be a homopolyester or a copolyester. In the case of a copolyester, it is usually a copolymer containing 30 mol% or less of the third component.

[0018] The polyester used in the present invention may be obtained by a melt polymerization reaction, or may be one obtained by solid-phase polymerization of a chipped polyester after melt polymerization.

[0019] In the present invention, the gist of the present invention is impaired in any of the polyester layers, which may be a single layer structure film or a film having a structure in which different types of polyesters are coextruded and laminated. If it is within the range, an antistatic agent or the like may be blended.

[0020] In order to adjust the surface roughness of the film and improve the slipperiness or abrasion resistance of the film, it is preferable to add inert inorganic or organic fine particles to the polyester. Examples of the particles include silicon oxide, alumina, calcium carbonate, calcium phosphate, kaolin, titanium oxide, barium sulfate, lithium fluoride, talc, and crosslinked polymer fine powder. These particles may be used alone or in combination of two or more components.

[0021] The content of the particles in the film is usually from 0.01 to:% by weight, preferably from 0.02 to 0.0.

5% by weight. When the film is a single layer film, the particle content in the film is used as the standard, and when the film is the multilayer film, the particle content in the surface layer is used as the standard.

When the content of the particles is low, the film surface becomes flat and the film slippage becomes worse, and not only the film manufacturing process but also the film running property and the rolling characteristics not only in the silicone resin coating process or the adhesive coating process. There is a tendency to be inferior. Also, if the particle content exceeds 1% by weight, the film surface becomes too rough and the silicone coating is applied. There is a tendency to deteriorate the peeling property of the surface.

[0022] The average particle size (measured by sedimentation method) of the above-mentioned particles added to the polyester film is usually 0.02 to 5 zm, preferably 0.02 to 3 zm.

[0023] Regarding the arithmetic average roughness Ra of the polyester film, a force that can be adjusted by the amount of added particles and the combination of the added particles, etc. In the present invention, Ra of each film surface is 0.01 to 0.15 xm. There is a need. When Ra is less than 0.01 zm, the film does not slide well and cannot be removed well, and the silicone layers on the front and back sides are more likely to be blocked. When Ra exceeds 0.15 / im, the releasability of the applied silicone becomes unstable, and a peeling abnormality / peeling defect that makes it difficult to obtain a light release property tends to occur.

Next, as an example of the method for producing a polyester film of the present invention, an example in which polyethylene terephthalate is used will be described, but the production conditions differ depending on the polyester used, and the present invention is not necessarily limited thereto. Although omitted here, the addition of particles or various additives to the polyester can be carried out at any stage from the polyester polymerization stage to the supply stage of the polyester resin to the extruder.

[0025] First, according to a conventional method, esterification is performed using terephthalic acid and ethylene glycol, or transesterification is performed using dimethyl terephthalate and ethylene glycol. Ethyl terephthalate (ΒΗΤ) is obtained. Next, while transferring the soot to the polymerization tank, it is heated to 280 ° C under vacuum to proceed the polymerization reaction to obtain a polyester.

[0026] Using an extruder, the polyester raw material is extruded from a die to form a molten sheet, and cooled and solidified with a cooling nozzle to obtain an unstretched sheet. The unstretched sheet is stretched in the first stage by a roll or tenter type stretching machine. The stretching temperature is usually 70 to 120 ° C, preferably 80 to 110 ° C, and the stretching ratio is usually 2.5 to 7 times, preferably 3.0 to 6 times. Next, stretching is performed in a direction orthogonal to the first-stage stretching direction. The stretching temperature in the second stage is usually 70 to 120 ° C, preferably 80 to 115 ° C, and the stretching ratio is usually 3.0 to 6 times, preferably 3.5 to 5 times. It is. Subsequently, heat treatment is performed at 130 ° C to 250 ° C under relaxation within 30% to obtain a biaxially stretched polyester film.

[0027] The thickness of the polyester film as the release film substrate of the present invention is determined according to its usage. Depending on the state, various thicknesses can be selected, but for a general pressure-sensitive adhesive release application, it is usually 25 to 125 μm.

[0028] In the release film of the present invention, the coating amount of the silicone resin coating film (after drying) Cw is in the range of ^{0. 04~0. 5g / m 2} . When Cw is 0.04 g / m ² or less, it is difficult to obtain a stable releasability, and abnormal releasability and poor releasability are likely to occur. On the other hand, when Cw is 0.5 g / m ² or more, in double-sided release film, silicone layer blocking phenomenon, transfer of silicone layer components, transfer trouble, reduced adhesion of adhesive layer due to silicone transfer This is likely to cause problems.

[0029] Since the Cw value as well as the Ra value described above are closely related to the properties of the release film, it is necessary to optimize the relationship between them. In the present invention, Cw / Ra is 0.7 to 15: In such a range, Ra of each substrate film surface and Cw of the silicone resin layer provided on the surface having the Ra are adjusted. If the Cw / Ra value on either side is less than 0.7, stable releasability cannot be obtained, resulting in poor releasability. Also, if the Cw / Ra value on either side exceeds 15, in the double-sided release film, blocking phenomenon between silicone layers, transfer of silicone layer components, transfer troubles, adhesive layer due to silicone transfer Problems such as reduced adhesion occur.

[0030] As the silicone resin used in the present invention, various commercially available release silicone resins can be used. These silicone resins can be addition-polymerized with a platinum catalyst, or can be condensation-polymerized with an organotin catalyst. In addition, there are a UV-crosslinking type and an electron beam cross-linking type in which radical polymerization or cationic polymerization is performed with a photopolymerization initiator.

[0031] Typically, an organic solvent dilution type silicone resin is used, and coating is performed using a coater. The coating method may be off-line coating in which the film is scraped off after film formation, or in-line coating in which coating is performed in the film production line.

[0032] In order to perform double-sided coating, there is a method of sequentially coating each side, but simultaneous double-sided coating with a double-sided simultaneous coating coater is preferable in terms of cost.

[0033] In the in-line coating, a water-based or solventless type silicone resin is usually used. In the film forming process, for example, the uniaxial stretching described above A silicone coating solution is applied to the subsequent film surface, and is dried and cured by heating in the transverse stretching-heat setting step in the transverse stretching tenter to obtain a silicone coating film. Even in the case of in-line coating, simultaneous application on both sides is possible, and industrially, a double-sided release film can be obtained at the lowest cost.

[0034] The release force of the release surface or release component transfer and transfer property of the release film is not limited to the selection of a silicone resin as a coating agent, but can be applied to a coating solution such as a release force adjusting agent or an adhesion enhancer. Addition and further, it can be adjusted by selecting a combination with the surface property of the base film.

[0035] Generally, a light release type silicone resin has light release properties, but has a high blooming, transfer and transfer properties. On the other hand, the heavy release type silicone resin does not adversely affect the adhesive properties of the adhesive layer with less blooming, transfer and transfer properties, but it is necessary to ensure an appropriate peeling force.

[0036] The releasability of the double-sided release film of the present invention is such that the peel force of the surface (A) having a light peel force (hereinafter referred to as a light peel surface) is FA (mN / cm) and has a heavy peel force. When the peel force of surface (B) (hereinafter referred to as the heavy peel surface) is FB (mN / cm), the ratio (FB / FA) is in the range of 1.0 to 4.0. (FA + FB) must be in the range of 10-100mN / cm. When FB / FA is less than 1.0, when the pressure-sensitive adhesive layer coating roll is squeezed out, the pressure-sensitive adhesive layer floats or the back surface of the pressure-sensitive adhesive layer occurs, or the light release surface (A) side At the time of peeling, the heavy peeling surface (B) may peel off first and cause trouble. Also, if FB / FA exceeds 4.0, there is a difference in peel force between the light release surface (A) of the double-sided release film and the heavy release surface (B), and the light release surface can be easily peeled off. However, workability when peeling the heavy release surface (B) becomes a problem.

If the FA + FB value is less than 1 OmN / cm, the release layer may be easily peeled off when handling the adhesive layer. If the FA + FB value exceeds lOOmNZcm, the peel force on the heavy peel surface (B) side becomes too heavy, causing heavy peel troubles.

[0037] From the viewpoint of blooming, transfer, and transferability, the residual adhesion ratio Zs on the surface of the silicone resin layer of the film of the present invention must be 85% or more on both sides, and this value is high. The more preferable. When the residual adhesive rate Zs is less than 85%, the decrease in the adhesive force on the adhesive surface of the pressure-sensitive adhesive layer becomes too large, which causes a problem. [0038] Examples of commercially available silicone resins include "KS _ 772", "KS-774", "KS-775", "KS-778", "KS-779H", " KS—847, KS—856, X—62—2422, “X—62—2461”, “X—62—1387”, “KNS—3051”, “K NS—3000”, “X — 62— 1256 ”,“ KM3950 ”,“ KM-768 ”,“ KM-9739 ”, etc .;“ DKQ3-202 ”,“ DKQ3-203 ”,“ DKQ3-204 ”,“ DKQ3_ ”manufactured by Dow Coaling Asia “205”, “DKQ3_210”, etc .; “YSR_3022,” “TPR-6700”, “TPR_6720”, “TPR_6721, etc.” manufactured by Toshiba Silicone; 39006VP ", etc., and can be appropriately selected from among them.

[0039] Normally, these silicone resins are added with a curing catalyst, if necessary, a peeling force adjusting agent, an adhesion reinforcing agent, and the like, and a solvent such as toluene, MEK, ethyl acetate, etc. Is diluted appropriately with water).

[0040] In the case of in-line coating, an emulsion-type aqueous silicone resin coating solution or a solventless silicone resin coating solution is usually used. When using an emulsion-type silicone resin coating solution, an aqueous coating solution containing a small amount of a water-miscible organic solvent or the like may be used to improve the coating properties.

[0041] The coating method of the silicone coating liquid on the base film includes a roll coating method, a gravure coating method, a micro gravure coating method, a reverse coating method, a reverse gravure coating method, a no-coating method, a Ronore brush method, an air Arbitrary coating methods such as knife coating, curtain coating, and die coating can be applied singly or in combination. Example

[0042] Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples as long as the gist thereof is not exceeded.

In addition, the evaluation method of the various characteristics in this invention is as follows.

[0043] (1) Arithmetic mean roughness (Ra):

Cotton (for example, manufactured by Asahi Kasei Co., Ltd.) with a silicone resin coating film containing a solvent (for example, toluene)

) Or with absorbent cotton, etc., and measure the exposed film surface with a cut-off value of 0.08 mm according to JIS B0601. [0044] (2) Peeling force:

Nitto Denko's “No. 502” double-sided adhesive tape's strong adhesive surface is shelled on the silicone side of the sample film, cut to 50mm x 300mm, and then 20-25 ° C / 50-60% RH atmosphere After leaving in the atmosphere for 1 hour, measure the peel force in the direction of 180 degrees at a tensile speed of 300 mm / min using a tensile tester in the atmosphere. The average peel force is the peel force (mNZcm).

[0045] (3) Residual adhesion rate:

First, “31B” adhesive tape manufactured by Nitto Denko Corporation is attached to the silicone surface of the sample film and heated at 100 ° C. for 1 hour. After standing for 1 hour, peel off the adhesive tape and measure the adhesive strength of this adhesive tape to the mirrorless stainless steel plate. The obtained adhesive strength is defined as sample adhesive strength.

Next, a “31B” adhesive tape manufactured by Nitto Denko Corporation is attached to the polytetrafluoroethylene film and heated at 100 ° C. for 1 hour. After leaving for 1 hour, peel off the adhesive tape and measure the adhesive strength of this adhesive tape to the mirror surface stainless steel plate. The obtained adhesive strength is defined as blank adhesive strength. Based on the following formula, the residual adhesion rate (%) is calculated from the sample adhesive strength and the blank adhesive strength.

[0047] [Equation 2]

Residual adhesion rate (%) = (Sample adhesion) X 1 0 0 Z (Blank adhesion) [0048] (4) Workability:

Check the following criteria when producing double-sided release films and during adhesive processing.

[0049] [Table 1

○: No trouble

X: Blocking of silicone coating layer on double-sided release film take-up roll

Phenomenon or peeling trouble occurs, or when the film is unwound from the winding adhesive roll after the adhesive processing, the adhesive layer floats from the release film, and the back side transfer of the adhesive layer occurs.

[0050] Example 1:

Polyethylene terephthalate (0.05% by weight of silica particles with an average particle size of about 2.

) Pellets of hot air dried at 180 ° C and supplied to an extruder, melt extruded from a T-die into a sheet at a temperature of 280 to 300 ° C, and electrostatically adhered to the mirror cooling drum. Cass G 'Quenched, unstretched Finolem with a thickness of about 613 xm, and then 85 this film. C was stretched 3.5 times in the longitudinal (longitudinal) direction to obtain a uniaxially stretched film. Bow I was continuously stretched in the transverse stretching zone at 110 to 150 ° C. and stretched 3.5 times in the transverse direction, and heat treatment was fixed at 230 ° C. to obtain a biaxially stretched polyester film XI having a thickness of 50 μm. Using a silicone coater, apply the following addition polymerization type thermosetting silicone coating solution (1) to this polyester film XI,

After passing through a drying oven at 160 ° C for 20 seconds and after drying and curing, a film having a release surface A1 with a coating amount of 0.1 lg / m ² was obtained. Double-sided release film having a release surface B 1 of 0.1 g / m ² after drying and curing, after passing through a drying oven at 160 ° C for a period of 20 seconds. F 1 was obtained.

[0051] Further, an acrylic adhesive coating solution having the following composition was applied to the B1 surface side of this double-sided release film F1 so that the coating thickness after drying was 25 μm, and dried at 130 ° C. The film was passed through the furnace with a passage time of 30 seconds, passed through a guide roll covered with a Teflon (registered trademark) tube and prevented from sticking, and was wound on the roll to obtain a double-sided release film N1 with an adhesive.

[0052] [Table 2]

[Silicone coating solution (1)]

• “KS—100 parts by weight, manufactured by Shin-Etsu Chemical Co., Ltd.”

779H "

• CAT-PL-8

• Toluene ZMEK = 1/1 mixture 2000 parts by weight

[Silicone coating solution (2)]

3650 "

• CAT—PL-50TJ

-Toluene / MEK = 1Z1 mixture 2000 parts by weight

[Acryl adhesive coating solution]

• Toyo Ink Manufacturing Co., Ltd. “Ori 100 parts by weight

Vine B P S 4429-4

Curing agent “BHS 8515”

• 50 parts by weight of toluene / MEK = 1Z1 mixture

[0053] Example 2:

In the film-forming process of Example 1, after -axial stretching, using a silicone coating liquid (3) having the composition shown below, double-sided coating was performed with varying coating amounts, and drying was performed in a transversely stretching tenter. By curing, a double-sided release film F2 having release surfaces A2 and B2 with coating thicknesses after drying of 0.12 g / m ² and 0.08 g / m 2 was obtained. [0054] [Table 3

[Silicone coating solution (3)]

• Asahi Kasei Softer Silicone 10 parts by weight

"DEHES I VE 39005 VP"

• "DEHES I VE 39006 VP" 10 parts by weight

• 100 parts by weight of ion exchange water

[0055] By the same operation as in Example 1, an acrylic pressure-sensitive adhesive was applied to the B2 surface side of the double-sided release film F2 so that the coating thickness after drying was 25 μm. N2 was obtained.

[0056] Comparative Example 1:

In the same manner as in Example 1, 2 wt% of silica particles having an average particle size of 3.5 111 were added to obtain a biaxially stretched polyester film Χ2 having a thickness of 50 μm, and then the above silicone coating liquid (1) and (2) was applied and processed in the same manner as in Example 1 to obtain a double-sided release film F3 having release surfaces A3 and B3 with a coating amount of 0.1 lgZm ² after drying and curing. In the same manner as in Example 1, an acrylic adhesive was applied to the B3 side of the double-sided release film F3 so that the coating thickness after drying was 25 μm, and the double-sided release film N3 with adhesive was applied. Obtained.

[0057] Comparative Example 2:

By using the silicone coating liquids (1) and (2) on the biaxially stretched polyester film XI having a thickness of 50 μm obtained in Example 1 and a silicone coater, the same operation as in Example 1 was performed. By coating and changing the coating amount, a double-sided release film F4 having release surfaces A4 and B4 with coating amounts after drying of 0.10 g / m ² and 0.02 g / m ² was obtained. In the same manner as in Example 1, the acrylic adhesive was applied to the B4 side of the double-sided release film F4 so that the coating thickness after drying was 25 μm, and the double-sided release film N4 with adhesive was applied. Obtained.

[0058] Comparative Example 3:

In the same manner as in Example 1, a 50 μm-thick biaxially stretched polyester film した 3 obtained by adding 0.01% by weight of silica particles having an average particle size of about 2.3 xm was obtained, and then the silicone coating solution was applied with a silicone coater. Using (1) and (2), a double-sided release film F5 having a release surface A5, B5 with a coating amount of 0.3 g / m ² after drying was applied in the same manner as in Example 1. Obtained. The force used for adhesive processing. It was difficult to obtain an ordinary double-sided release film with an adhesive.

[0059] Comparative Example 4:

To the biaxially stretched polyester film XI having a thickness of 50 μm obtained in Example 1, a silicone coating liquid (4) having the following composition and the silicone coating liquid (2) having the composition shown below were coated with a silicone coater. Using the same coating process as in Example 1 and changing the coating amount, the coating amount after drying was 0.

A double-sided release film F6 having a release surface A6, B6 of 0.20 gZm ² was obtained. In the same manner as in Example 1, an acrylic pressure-sensitive adhesive was applied to the B6 side of the double-sided release film F6 so as to have a coating thickness of 25 μm after drying to obtain a double-sided release film N6 with pressure-sensitive adhesive.

[0060] [Table 4

[Silicone coating solution (4)]

-100 parts by weight of “KS— 8 3 5” manufactured by Shin-Etsu Chemical Co., Ltd.

• “CAT— P L— 50 T” 1 part by weight

'Toluene / MEK = 1Z1 mixture: 2000 parts by weight

[0061] The results obtained are shown in Table 5 below. The double-sided release films of Examples 1 and 2 were able to be stably subjected to pressure-sensitive adhesive processing and satisfied release characteristics required for double-sided pressure-sensitive adhesive sheet applications. On the other hand, in Comparative Examples 1 to 4, some trouble occurred during the production of the double-sided release film or the processing of the adhesive resin, and all of the release characteristics required for the double-sided adhesive sheet were satisfied. There wasn't.

[0062] [Table 5]

Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4

R a (^ ni) 0.03 0.03 0.34 0.03 0.01 0.03 Silicone coating solution

Minoh (1) (3) (1) (1) (1) (4)

Side B (2) (3) (2) (2) (2) (2)

C w (g / m 2)

Side A 0.10 0.12 0.10 0.10 0.30 0.60

Side B 0.10 0.08 0.10 0.02 0.30 0.20

C w / R a

Side A 3.3 4.0 0.3 3.3 30 20

Side B 3.3 2.7 0.3 0.7 30 6.7

F A (mN / cm) 14 13 200 14 12 12

F B (mN / cm) 21 17 350 70 16 18

F A + F B

35 30 550 84 28 30 (mN / cm)

F B / F A 35 30 550 84 28 30

Z s (%)

Side A 93 97 98 90 83 80

Side B 99 99 100 100 88 90 Processability ○ ○ ○ ○ XX Overall results ○ ○ XXXX Above, the present invention has been described in relation to the most practical and preferred embodiment at present. The present invention is not limited to the embodiments disclosed in the specification of the present application, and can be appropriately changed without departing from the spirit or idea of the invention which can be read from the claims and the entire specification. It is to be understood that any change is also within the technical scope of the present invention.

Claims

Claims A double-sided release film comprising a polyester film and a silicone resin coating film formed on both sides of the polyester film, wherein the following formulas (1) to (6) are satisfied at the same time: Double-sided release film. [Equation 1] 0. 0 l≤Ra≤0. 15 (1) 0. 04≤Cw≤0. 5 (2) 0. 7≤Cw / R a≤ 15 (3)

1. 0≤FB / FA≤4.0 (4)

10≤FA + FB≤ 100 (5)

85≤Z s (6)

(In the above formula, Ra is the arithmetic mean roughness of the polyester film surface (μm), Cw is the coating amount of the silicone resin coating film (g / m ² ), FA is the silicone resin coating surface of the one having a light release force) Peeling force (mN / cm), FB is the peeling force (mN / cm) of the silicone resin coating surface with heavy peeling force, and Zs is the residual adhesion rate (%) of the silicone resin coating surface)