KR101427504B1 - Method for selecting separator, and pressure-sensitive adhesive sheet using separator selected by the method - Google Patents

Abstract

A method of easily selecting a separator suitable for a pressure-sensitive adhesive sheet is provided. The selecting method of the present invention is characterized by a step of obtaining an adhesive sheet having at least a pressure-sensitive adhesive layer and a separator bonded to the separator in a state in which a material forming at least the pressure-sensitive adhesive layer is melted, the separator being peeled off from the obtained pressure- A pressure-sensitive adhesive sheet for evaluation and a pressure-sensitive adhesive sheet for pressure-sensitive adhesive sheet, and a pressure-sensitive adhesive layer for evaluation and a separator for evaluation, Minute, and then peeling off the separator for evaluation by a 180 ° peel test at a peel rate of 300 mm / min.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a pressure-sensitive adhesive sheet using a separator selected by a separator selection method and a method of selecting the pressure-

The present invention relates to a method of selecting a separator and a pressure-sensitive adhesive sheet using the separator selected by the method.

As a production method of a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer and a base layer, there is known a molding method in which a material constituting the base layer and a material constituting the pressure-sensitive adhesive layer are pneumatically delivered because of excellent production efficiency and cost- Document 1). Further, the pressure-sensitive adhesive sheet is usually provided with a separator so as to contact with the pressure-sensitive adhesive layer as a protective material until used. In such a pressure-sensitive adhesive sheet, when the pressure-sensitive adhesive sheet is formed by co-extrusion, foreign matter can be prevented from entering the pressure-sensitive adhesive layer and between the pressure-sensitive adhesive layer and the separator, and a pressure-sensitive adhesive sheet having a smooth surface, A method of joining the extruded pressure-sensitive adhesive layer-forming material with the separator in a molten state has been studied. However, in the pressure-sensitive adhesive sheet thus obtained, separation of the separator becomes difficult, and handling properties of the pressure-sensitive adhesive sheet often deteriorate. In addition, the use of a light separating separator against such a problem improves the handling property, but the adhesive strength of the pressure-sensitive adhesive layer often decreases during storage of the pressure-sensitive adhesive sheet. As described above, it is difficult to make both the good handling property of the pressure-sensitive adhesive sheet and the appropriate adhesive force compatible.

The separator to be used for the pressure-sensitive adhesive sheet is appropriately selected according to the kind of the releasing agent, the peeling force thereof, and the like. However, as described above, in the case of bonding to the melted pressure-sensitive adhesive layer-forming material, the pressure-sensitive adhesive sheet obtained may not exhibit the inherent ability of the separator. Therefore, in the separator to be used in the pressure-sensitive adhesive sheet produced by the melt co-extrusion molding, it is necessary to first examine the suitability of the separator after the adhesive sheet is actually produced by selecting the separator as the candidate. Therefore, every time the structure of the pressure-sensitive adhesive sheet is changed, it is necessary to prepare a pressure-sensitive adhesive sheet to examine the suitability of the separator, and it is not easy to select an appropriate separator.

Japanese Patent Application Laid-Open No. 2009-275209

An object of the present invention is to provide a method for easily selecting a separator suitable for a pressure-sensitive adhesive sheet having at least a pressure-sensitive adhesive layer.

A method for selecting a separator according to the present invention comprises the steps of: obtaining a pressure-sensitive adhesive sheet having at least a pressure-sensitive adhesive layer and a separator bonded to a separator in a state in which a material forming at least a pressure-sensitive adhesive layer is melted; separating the separator from the pressure- A step of bonding the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet to the evaluation separator to form an evaluation pressure-sensitive adhesive sheet; and a step of sandwiching the pressure-sensitive adhesive sheet for evaluation between a pair of cushioning materials and a pair of press plates, And then evaluating the peelability of the separator for evaluation by a 180 ° peel test at a peel rate of 300 mm / min.

In a preferred embodiment, a separator having a peeling force measured in the evaluation step is 2.0 N / 50 mm or less is selected.

In a preferred embodiment, the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet comprises a polyolefin-based resin.

In a preferred embodiment, the polyolefin-based resin comprises an amorphous propylene- (1-butene) copolymer polymerized using a metallocene catalyst.

In another embodiment of the present invention, a pressure-sensitive adhesive sheet is provided. The pressure-sensitive adhesive sheet includes a base layer, a pressure-sensitive adhesive layer, and a separator selected by the above-mentioned selection method.

According to the present invention, a separator suitable for a pressure-sensitive adhesive sheet can be easily selected.

The method for selecting a separator of the present invention is a method for selecting a separator suitable for a pressure-sensitive adhesive sheet. According to the method of the present invention, a separator suitable for a pressure-sensitive adhesive sheet obtained by bonding at least the material forming the pressure-sensitive adhesive layer to the separator in a molten state can be easily selected. A method for selecting a separator according to the present invention comprises the steps of: obtaining a pressure-sensitive adhesive sheet having at least a pressure-sensitive adhesive layer and a separator bonded to a separator in a state in which a material forming at least a pressure-sensitive adhesive layer is melted; separating the separator from the pressure- A step of bonding the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet to the evaluation separator to form an evaluation pressure-sensitive adhesive sheet; and a step of sandwiching the pressure-sensitive adhesive sheet for evaluation between a pair of cushioning members and a pair of press plates, And then evaluating the peelability of the separator for evaluation by a 180 ° peel test at a peel rate of 300 mm / min. By selecting the separating force of the separator according to the present invention, a separator suitable for the adhesive sheet can be easily selected.

A. At least The pressure- The separator  A step of obtaining a pressure-sensitive adhesive sheet having

The selection method of the present invention includes a step of obtaining an adhesive sheet having at least a pressure-sensitive adhesive layer and a separator bonded to the separator in a state in which a material forming at least the pressure-sensitive adhesive layer is melted. The pressure-sensitive adhesive sheet typically has a base layer, a pressure-sensitive adhesive layer, and a separator in this order.

The method for forming the pressure-sensitive adhesive sheet is not particularly limited and may include a step of bonding at least the material forming the pressure-sensitive adhesive layer to the separator in a molten state. The molding method includes a step of, for example, melting a material forming the pressure-sensitive adhesive layer and a material forming the base layer and then extruding them to obtain a laminate of a pressure-sensitive adhesive layer and a base layer; And a step of bonding the pressure-sensitive adhesive layer of the laminate to the separator to obtain a pressure-sensitive adhesive sheet.

In the step of obtaining the laminate of the pressure-sensitive adhesive layer and the base layer, the laminate may be formed, for example, of a material for forming a pressure-sensitive adhesive layer on one of at least two extruders connected to a die, Respectively, melting them, and then extruding them. The conditions (for example, die temperature) for forming the pressure-sensitive adhesive sheet can be appropriately set according to the material constituting each layer of the pressure-sensitive adhesive sheet. For example, the die temperature may be set to a temperature at which the forming material of each layer of the pressure-sensitive adhesive sheet becomes a molten state. In one embodiment, the die temperature may be set at 160 ° C to 220 ° C.

Specifically, in the step of obtaining the laminate, the step of bonding the laminate and the separator may be such that at least a material forming the pressure-sensitive adhesive layer of the extruded laminate is melted and the pressure- And then pulling it by a touch roll forming method. The conditions for bringing the material forming the pressure-sensitive adhesive layer into contact with the separator (for example, the temperature and the contact pressure for bringing the material constituting the pressure-sensitive adhesive layer into contact with the separator) can be appropriately set according to the material constituting each layer of the pressure- . For example, the temperature at which the material constituting the pressure-sensitive adhesive layer and the separator are brought into contact with each other may be set at a temperature such that at least the material forming the pressure-sensitive adhesive layer remains in a molten state. In one embodiment, the temperature at which the material constituting the pressure-sensitive adhesive layer and the separator are brought into contact with each other may be set to 120 deg. C to 200 deg.

Any suitable separator may be used as the separator used in this step (hereinafter also referred to as a separator for production). For example, a separator generally used as a separator of a pressure-sensitive adhesive sheet in the art can be used. Specific examples thereof include MRF-38, a product of Mitsubishi Plastics, and HY-S06, a product of Higashiyama Film Co., Ltd.

B. Manufacturing process of pressure-sensitive adhesive sheet for evaluation

The pressure-sensitive adhesive sheet for evaluation used in the evaluation step in the selection method of the present invention is obtained as follows. First, the separator is peeled off from the pressure-sensitive adhesive sheet obtained by the method of the above-mentioned A. The peeling of the separator can be performed by any suitable means, and may be peeled off using any suitable peeling machine, or peeled off by hand.

Then, the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet from which the separator is peeled is joined to the evaluation separator to be selected. It is not necessary to strongly bond the adhesive sheet and the evaluation separator in the step of manufacturing the adhesive sheet for evaluation because the pressing is performed in the step of evaluating the peeling force which will be described later and the laminated state of the adhesive sheet and the evaluation separator So long as it is maintained.

C. Evaluation Separator Peel force  Evaluation process

The peeling force evaluation step of the separator for evaluation is performed as follows. The pressure-sensitive adhesive sheet for evaluation obtained in the above step B is sandwiched between a pair of cushioning members, and held between a pair of press plates and held at a press plate surface temperature of 140 DEG C and a pressure of 5 MPa for 1 minute. The separator used in the pressure-sensitive adhesive sheet tends to be very difficult to peel off the separator and the pressure-sensitive adhesive layer when the press plate surface temperature exceeds 140 캜. Therefore, a separator suitable as a separator of the pressure-sensitive adhesive sheet can be selected by pressing the pressure-sensitive adhesive sheet at a press plate surface temperature of 140 캜 and evaluating the peeling force of the separator for evaluation in the pressure-sensitive adhesive sheet after pressing. On the other hand, the press plate surface temperature in the peeling force evaluation test of the present invention refers to the temperature of the press plate surface.

In the press, a cushioning material is disposed between the pressure-sensitive adhesive sheet for evaluation and the press plate to prevent excessive pressure from being applied to the pressure-sensitive adhesive sheet. As this cushioning material, any suitable cushioning material applicable to a hot press can be used. Examples of the cushioning material include rubber, heat-resistant elastomer, a combination of organic or inorganic fibers with a binder, a nonwoven fabric, and a laminate of rubber and nonwoven fabric. A suitable cushioning material may be selected and used so that the pressure applied to the pressure-sensitive adhesive sheet for evaluation is a proper pressure. For example, by adjusting the constituent material and size (area) of the cushioning material, the pressure applied to the pressure-sensitive adhesive sheet for evaluation can be adjusted. More specifically, for a separator having a size of 150 mm x 200 mm, a rubber plate having an area of 130 mm x 160 mm may be used.

Further, in order to prevent blocking of the cushioning material and the evaluation pressure-sensitive adhesive sheet at the time of pressing, a resin sheet may be disposed between the cushioning material and the pressure-sensitive adhesive sheet for evaluation, and the pressure may be applied. The resin sheet may be a resin sheet applicable as a separator, and any suitable sheet can be used. For example, a polyethylene terephthalate resin sheet, a polyimide resin film, or the like can be used. The thickness of the resin sheet is usually 38 mu m to 75 mu m.

The press of the pressure-sensitive adhesive sheet for evaluation can be carried out by using any suitable means capable of setting the press plate surface temperature and pressure. For example, it can be carried out by using a commercially available press machine, specifically MINI TEST PRESS-10 manufactured by Toyo Seiki Seisakusho.

The pressure-sensitive adhesive sheet for evaluation after pressing is left to stand at room temperature, and the peeling test of the separator for evaluation is carried out. The peeling test is conducted by peeling the separator for evaluation at a peeling speed of 300 mm / min and a peeling angle of 180 °.

From the peeling force measured by the peeling test, a desired separator can be selected according to the characteristics required for the separator. For example, when a separator having an excellent handling property and an appropriate adhesive strength is desired, a separator having a peeling force measured by the peeling test of 2.0 N / 50 mm or less can be suitably used. Further, when a separator having higher adhesion between the pressure-sensitive adhesive layer and the separator is desired, a separator having a peeling force of 2.0 N / 50 mm or more as measured by the above separation test may be used. In view of handling in a commercially available tape adhering apparatus (for example, an apparatus for attaching a protective tape for back grinding for a product made by Nitto Jung Co., Ltd., product name: DR3000III, etc.), the peeling force measured by the peeling test is 2.0 N / Can be selected. On the other hand, when a separator having higher handling properties is desired, a separator having a smaller peeling force as measured by the peeling test may be used.

D. Pressure sensitive adhesive sheet

The pressure-sensitive adhesive sheet to which the present invention is applied typically includes a base layer, a pressure-sensitive adhesive layer, and a separator. In addition, the pressure-sensitive adhesive sheet may include any other appropriate layer as necessary. Examples of the other layer include a surface layer which imparts heat resistance.

The thickness of the pressure-sensitive adhesive sheet (excluding the thickness of the separator) is preferably 90 占 퐉 to 285 占 퐉, more preferably 105 占 퐉 to 225 占 퐉, and still more preferably 130 占 퐉 to 210 占 퐉.

D-1. Separator

The separator is selected by the separator selecting method of the present invention. The separator usually has a base layer and a release agent layer. The base layer and the release agent layer may be composed of any suitable material. Preferably, the separator has a peeling force of 2.0 N / 50 mm or less, more preferably 0.05 N / 50 mm to 2.0 N / 50 mm, more preferably 0.05 N / 50 mm To 1.8 N / 50 mm. By using such a separator, a pressure-sensitive adhesive sheet having excellent handling properties and maintaining an appropriate adhesive strength can be obtained. In the case of a pressure-sensitive adhesive sheet in which the separator is less likely to be peeled off from the pressure-sensitive adhesive layer, a separator having a peeling force exceeding 2.0 N / 50 mm evaluated by the method of the present invention may be used.

The thickness of the separator is not particularly limited and may be set to any suitable thickness. The thickness of the separator can be set to, for example, 25 mu m to 250 mu m.

D-2. The pressure-

The pressure-sensitive adhesive layer may be composed of any suitable pressure-sensitive adhesive, and may include, for example, a pressure-sensitive adhesive containing a thermoplastic resin such as a polyolefin resin, an acrylic resin or a styrene resin. The pressure-sensitive adhesive layer preferably comprises a polyolefin-based resin, and specifically includes a low-density polyethylene, a very low-density polyethylene, a low-crystalline polypropylene, an amorphous propylene- (1-butene) copolymer, an ionomer resin, an ethylene- , Ethylene- (meth) acrylic acid copolymer, ethylene- (meth) acrylic acid ester-maleic anhydride copolymer, and ethylene-methacrylic acid glycidyl copolymer, and polyolefin-modified polymers. The pressure-sensitive adhesive layer more preferably comprises an amorphous propylene- (1-butene) copolymer. By using such a pressure-sensitive adhesive layer, it is possible to obtain a pressure-sensitive adhesive sheet which is less contaminated with an adherend, has both adhesive force and releasability, and can be produced by co-extrusion molding. Furthermore, in the case of such a pressure-sensitive adhesive layer, the pressure-sensitive adhesive sheet can be produced by co-extrusion molding with the base layer, and a pressure-sensitive adhesive sheet can be obtained with fewer steps and without using an organic solvent. In the present specification, the term " amorphous " refers to a property having no definite melting point like crystalline.

The amorphous propylene- (1-butene) copolymer is preferably obtained by polymerizing propylene and 1-butene using a metallocene catalyst. More specifically, the amorphous propylene- (1-butene) copolymer is obtained by carrying out a polymerization process in which propylene and 1-butene are polymerized, for example, using a metallocene catalyst, and after the polymerization process, Followed by a post-treatment step such as a treatment. The amorphous propylene- (1-butene) copolymer is obtained in the form of, for example, a powder or a pellet through such a process. Examples of the metallocene catalyst include a homogeneously mixed metallocene catalyst containing a metallocene compound and an aluminoxane, and a metallocene supported catalyst having a metallocene compound supported on a particulate carrier. Amorphous propylene- (1-butene) copolymers polymerized using a metallocene catalyst exhibit a narrow molecular weight distribution.

In the amorphous propylene- (1-butene) copolymer, the content ratio of propylene-derived structural units is preferably 80% by mole to 99% by mole, more preferably 85% by mole to 99% by mole, Is from 90 mol% to 99 mol%.

The content of the constituent unit derived from 1-butene in the amorphous propylene- (1-butene) copolymer is preferably 1 mol% to 15 mol%, and more preferably 1 mol% to 10 mol%. In such a range, a pressure-sensitive adhesive sheet having excellent balance between toughness and flexibility can be obtained.

The amorphous propylene- (1-butene) copolymer may be a block copolymer or a random copolymer.

The amorphous propylene- (1-butene) copolymer may further contain other monomer-derived constituent units insofar as the effect of the present invention is not impaired. Examples of other monomers include? -Olefins such as ethylene, 1-pentene, 1-hexene, 1-octene, 1-decene, 4-methyl-1-pentene and 3-methyl-1-pentene.

The pressure-sensitive adhesive layer may further contain other components as long as the effect of the present invention is not impaired. Examples of the other components include antioxidants, ultraviolet absorbers, light stabilizers, heat stabilizers, antistatic agents and the like. The kinds and amounts of the other components can be appropriately selected depending on the purpose.

The thickness of the pressure-sensitive adhesive layer is preferably 20 to 100 占 퐉, more preferably 30 to 65 占 퐉.

D-3. The substrate layer

The base layer can be formed using any suitable material, and examples thereof include polyesters (such as polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, and polybutylene terephthalate), polyolefins (such as polyethylene, Propylene copolymer, etc.), polyvinyl alcohol, polyvinylidene chloride, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, ethylene-vinyl acetate copolymer, polyvinyl acetate, polyamide, polyimide, cellulose, Resins, polyethers, polystyrene resins (such as polystyrene), polycarbonates, and polyethersulfone. Preferably, the substrate layer comprises an ethylene-vinyl acetate copolymer.

The base layer may further contain other components as long as the effect of the present invention is not impaired. As the other component, for example, the same components as the other components that can be contained in the pressure-sensitive adhesive layer described above can be used.

The thickness of the base layer is preferably 30 m to 185 m, more preferably 65 m to 175 m.

D-4. Other floors

As another layer included in the adhesive sheet of the present invention, for example, a surface layer capable of imparting heat resistance to the adhesive sheet can be mentioned. Any suitable resin having heat resistance may be used for the surface layer, and preferably a polypropylene resin. The polypropylene resin is preferably obtained by polymerization using a metallocene catalyst. More specifically, the polypropylene resin is obtained by carrying out a polymerization process for polymerizing a monomer composition containing propylene by using, for example, a metallocene catalyst, and performing post-treatment such as a catalyst residue removal process, And then carrying out the process. The polypropylene resin can be obtained in the form of powder, pellet or the like through such processes. Examples of the metallocene catalyst include those exemplified above.

Commercially available products of the polypropylene resin may be used. Specific examples of commercially available polypropylene resins include trade names "WINTEC (Wintec)" and "WELNEX (Welnex)" manufactured by Nippon Polypro Corporation.

The surface layer may further contain other components so long as the effect of the present invention is not impaired. As the other component, the same components as the other components that can be contained in the pressure-sensitive adhesive layer described above can be mentioned. The kinds and amounts of the other components can be appropriately selected depending on the purpose.

Example

Hereinafter, the present invention will be described in detail by way of examples, but the present invention is not limited to these examples. On the other hand, the test and evaluation methods in Examples and the like are as follows. Further, parts means parts by weight.

(Reference Example 1) Production of pressure-sensitive adhesive sheet for test

(Trade name: WELNEX: RFGV4A; melting point: 130 占 폚, softening point: 120 占 폚, Mw / Mn = 2.9) were used.

As a material for forming the substrate layer, an ethylene-vinyl acetate copolymer (trade name "Evaplex P-1007" manufactured by Mitsui Dupont Co., Ltd.) was used.

As a material for forming the pressure-sensitive adhesive layer, an amorphous propylene- (1-butene) copolymer (trade name: "Tafselen H5002" manufactured by Sumitomo Chemical Co., Ltd.: a constituent unit derived from propylene: 90 mol% 10 mol%, Mw = 230,000, and Mw / Mn = 1.8) were used.

100 parts of the material for forming the surface layer, 100 parts of the material for forming the base layer and 100 parts of the material for forming the pressure-sensitive adhesive layer were put in respective extruders and T-die co-extruded (die temperature: 180 DEG C). (Air gap: 150 mm, contact temperature: 165 占 폚) was adhered to a pressure-sensitive adhesive layer of a laminate of a surface layer / base layer / pressure-sensitive adhesive layer co-extruded from a die ) Surface layer (thickness 30 占 퐉) / base layer (thickness 130 占 퐉) / pressure-sensitive adhesive layer (thickness 45 占 퐉) / separator. On the other hand, the thicknesses of the surface layer, the base layer and the pressure-sensitive adhesive layer were controlled by the shape of the T die outlet.

[Example 1] Selection of a separator suitable for a pressure-sensitive adhesive sheet

(Evaluation Separator 1)

The separator on the pressure-sensitive adhesive layer side was peeled from the pressure-sensitive adhesive sheet obtained in Reference Example 1. [ Then, a separator for evaluation 1 (manufactured by Higashiyama Film Co., Ltd., HY-S30, thickness: 38 mu m) was bonded to the pressure-sensitive adhesive layer to obtain a pressure-sensitive adhesive sheet for evaluation.

The resulting pressure-sensitive adhesive sheet for evaluation was pressed using a press machine (MINI TEST PRESS-10, surface area: 250 mm x 250 mm). MRN38 made of Mitsubishi resin was used as a resin sheet (separator), and a rubber plate (thickness: 1 mm, 130 mm x 160 mm) was used as a cushioning material. The pressure-sensitive adhesive sheet for evaluation was laminated in the order of a stainless plate (SUS plate) / resin sheet / cushioning material / resin sheet / adhesive sheet for evaluation / resin sheet / cushioning material / resin sheet / stainless plate, The temperature was maintained at 140 占 폚 and a press pressure of 5 MPa for 1 minute. Subsequently, the pressure-sensitive adhesive sheet was allowed to stand at room temperature, and the peeling force (peeling speed: 300 mm / min, peeling angle: 180 deg.) Of the separator for evaluation of the pressure-sensitive adhesive sheet was measured. Table 1 shows the measured peel force.

(Separator for evaluation 2)

The peeling force of the separator for evaluation was measured in the same manner as in the evaluation separator 1 except that the evaluation separator 2 (HY-TS11, manufactured by Higashiyama Film Co., Ltd., thickness 75 탆) was used instead of the evaluation separator 1. Table 1 shows the measured peel force.

(Evaluation Separator 3)

The peeling force of the separator for evaluation was measured in the same manner as in the evaluation separator 1 except that the separator for evaluation 3 (manufactured by Higashiyama Film, HY-TS15, thickness 75 탆) was used in place of the separator for evaluation 1. Table 1 shows the measured peel force.

(Separator for evaluation 4)

The peeling force of the separator for evaluation was measured in the same manner as in the evaluation separator 1 except that the evaluation separator 4 (MRE38, thickness 38 占 퐉, manufactured by Mitsubishi Plastics, Inc.) was used instead of the evaluation separator 1. Table 1 shows the measured peel force.

(Evaluation Separator 5)

The peeling force of the separator for evaluation was measured in the same manner as in the evaluation separator 1 except that the evaluation separator 5 (MRN38, manufactured by Mitsubishi Plastics, Inc., thickness: 38 m) was used instead of the evaluation separator 1. Table 1 shows the measured peel force.

(Evaluation Separator 6)

The peeling force of the separator for evaluation was measured in the same manner as in the evaluation separator 1 except that the evaluation separator 6 (MRF38, thickness 38 占 퐉, manufactured by Mitsubishi Plastics, Inc.) was used instead of the evaluation separator 1. Table 1 shows the measured peel force.

(Evaluation Separator 7)

The peeling force of the separator for evaluation was measured in the same manner as in the evaluation separator 1 except that the evaluation separator 7 (manufactured by Higashiyama Film, HY-S10, thickness 75 탆) was used in place of the separator for evaluation 1. Table 1 shows the measured peel force.

(Separator for evaluation 8)

The peeling force of the separator for evaluation was measured in the same manner as in the evaluation separator 1 except that the evaluation separator 8 (manufactured by Higashiyama Film, HY-S06, thickness 75 탆) was used instead of the evaluation separator 1. Table 1 shows the measured peel force.

(Evaluation Separator 9)

The peeling force of the separator for evaluation was measured in the same manner as in the evaluation separator 1, except that the evaluation separator 9 (HY-TS05G, thickness 75 占 퐉, manufactured by Higashiyama Film Co., Ltd.) was used instead of the evaluation separator 1. Table 1 shows the measured peel force.

(Evaluation Separator 10)

The peeling force of the separator for evaluation was measured in the same manner as in the evaluation separator 1 except that the evaluation separator 10 (HY-US20, thickness: 75 占 퐉, manufactured by Higashiyama Film Co., Ltd.) was used instead of the evaluation separator 1. Table 1 shows the measured peel force.

[Example 2] Evaluation of a pressure-sensitive adhesive sheet using a selected separator

Adhesive sheets 1 to 10 were obtained in the same manner as in Reference Example 1 except that the separators 1 to 10 for evaluation were used. The resulting pressure-sensitive adhesive sheets 1 to 10 were provided in the following evaluations. The results are shown in Table 2.

[evaluation]

(1) Peeling force of separator

The peel strength (peel rate: 300 mm / min, peel angle: 180 DEG) of the separator in the obtained pressure-sensitive adhesive sheet was measured.

(2) Adhesive strength of the pressure-sensitive adhesive layer

The obtained pressure-sensitive adhesive sheet was aged at 50 占 폚 for 2 days, peeled off the separator bonded to the pressure-sensitive adhesive layer, and adhered to the mirror surface (made of silicone) of the 4-inch semiconductor wafer of the pressure-sensitive adhesive layer according to JIS Z 0237 (Bonding condition: one reciprocation of 2 kg roller, peeling speed: 300 mm / min, peeling angle of 180). When the measured value is 0.005 N / 20 mm or more, the adhesive sheet has sufficient adhesive strength.

The pressure-sensitive adhesive sheets 1 to 5 using the separators 1 to 5 having a peeling force of 2.0 N / 50 mm or less as measured in Example 1 were easy to peel the separator and adhered firmly to the pressure-sensitive adhesive layer. In the case of the pressure-sensitive adhesive sheets 6 to 10 using the separators 6 to 10 having a peel strength of 2.0 N / 50 mm or more as measured in Example 1, the force required to peel the separator from the separators 1 to 5 was large.

The method for selecting the separator of the present invention can be suitably used, for example, in selecting a separator for use in a pressure-sensitive adhesive sheet.

Claims (5)

A step of obtaining a pressure-sensitive adhesive sheet having at least a pressure-sensitive adhesive layer and a separator bonded to the separator in a state in which a material forming at least the pressure-sensitive adhesive layer is melted,
Peeling the separator from the obtained pressure-sensitive adhesive sheet, bonding the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet to the evaluation separator to manufacture an adhesive sheet for evaluation,
The pressure-sensitive adhesive sheet for evaluation was sandwiched between a pair of cushioning members and a pair of press plates, held at a press plate surface temperature of 140 DEG C and a pressure of 5 MPa for 1 minute, and then subjected to a 180 DEG peeling test at a peeling speed of 300 mm / A step of evaluating the separating force of the separator, and
And a step of selecting a separator for a pressure-sensitive adhesive sheet based on the peeling force measured in the evaluation step. The method according to claim 1,
And a separator having a peeling force measured in the evaluation step is 2.0 N / 50 mm or less. The method according to claim 1,
Wherein the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet comprises a polyolefin-based resin. The method of claim 3,
Wherein the polyolefin-based resin is polymerized using a metallocene catalyst. 2. The separator according to claim 1, wherein the polyolefin-based resin is an amorphous propylene- (1-butene) copolymer. A pressure-sensitive adhesive sheet comprising a substrate layer, a pressure-sensitive adhesive layer, and a separator selected by the method according to claim 1.