JP2018016727A - Double-sided adhesive sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a double-sided adhesive sheet with a release liner, easy to carry out a removal operation of the release liner, appropriate for preventing a partial breakage or defect of an adhesive layer when removing the release liner, and appropriate for efficient production.SOLUTION: An adhesive sheet X1, which is a double-sided adhesive sheet of this invention, has a laminate structure including an adhesive sheet body 10, which is a double-sided adhesive sheet main body, and release liners L1, L2. The adhesive sheet body 10 includes at least one adhesive layer 11, and is positioned between the release liners L1, L2. At least part of an area of an outer peripheral end 11a of the adhesive layer 11 is 5-2000 μm inward from an outer peripheral end L1a of the release liner L1 and an outer peripheral end L2a of the release liner L2 in a sheet plane direction.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a double-sided pressure-sensitive adhesive sheet with a release liner.

  In recent years, double-sided pressure-sensitive adhesive sheets having high transparency have been used in various technical fields. For example, in the technical field of flat panel displays, optical double-sided pressure-sensitive adhesive sheets are used in the production of display devices and the like. Specifically, a display device such as a liquid crystal display and an input device such as a touch panel have a laminated structure including various substrates and film bodies, and in order to join between predetermined parts adjacent in the laminated structure, Alternatively, a transparent double-sided pressure-sensitive adhesive sheet may be used to fill a gap between adjacent parts. About such a double-sided adhesive sheet, it describes in the following patent documents 1-3, for example.

JP 2012-188595 A Japanese Patent Laid-Open No. 2015-200698 Japanese Unexamined Patent Publication No. 2016-26321

  The double-sided PSA sheet may be manufactured and shipped in a mode in which both PSA sides are covered with a pair of release liners. For such double-sided pressure-sensitive adhesive sheets with release liners, each release liner is peeled from the double-sided pressure-sensitive adhesive sheet body at a predetermined timing in use. It may be required to be easy.

  Conventionally, when one release liner is peeled from the double-sided pressure-sensitive adhesive sheet main body with the release liner on both pressure-sensitive adhesive surfaces, a part of the pressure-sensitive adhesive surface of the double-sided pressure-sensitive adhesive sheet body is pulled by the release liner, and the pressure-sensitive adhesive surface Or the adhesive layer may be partially damaged or broken.

  The present invention has been conceived under the circumstances as described above, and facilitates the release operation of the release liner and suppresses partial breakage or loss of the adhesive layer when the release liner is peeled off. Another object of the present invention is to provide a double-sided pressure-sensitive adhesive sheet with a release liner that is suitable for efficient production.

  The double-sided pressure-sensitive adhesive sheet provided by the first aspect of the present invention includes a laminated structure including a first release liner, a second release liner, and a double-sided pressure-sensitive adhesive sheet body positioned between the first and second release liners. Have The double-sided PSA sheet body has at least one PSA layer. Such a double-sided pressure-sensitive adhesive sheet main body may be constituted by a single pressure-sensitive adhesive layer, or has a laminated structure including two pressure-sensitive adhesive layers forming both pressure-sensitive adhesive surfaces and a base material between the pressure-sensitive adhesive layers. May be. In addition, at least a part of the outer peripheral edge of the pressure-sensitive adhesive layer in the double-sided pressure-sensitive adhesive sheet body is 5 to 2000 μm inward from the outer peripheral edge of the first release liner and the outer peripheral edge of the second release liner in the in-plane direction. Is in the distance. The sheet in-plane direction refers to the in-plane direction of the double-sided PSA sheet or the double-sided PSA sheet body. In such a sheet in-plane direction, at least a part of the outer peripheral edge of the pressure-sensitive adhesive layer is at a distance of 5 to 2000 μm inward of the sheet with respect to the outer peripheral edge closest to the first release liner, And it exists in the distance of 5-2000 micrometers inward of a sheet | seat with respect to the outer peripheral edge nearest to the 2nd release liner.

  As described above, at least a part of the outer peripheral edge of the pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive main body in the double-sided pressure-sensitive adhesive sheet with a release liner is the outer peripheral edge of the first release liner and the second edge in the sheet in-plane direction. There is a distance of 5 to 2000 μm inward from each of the outer peripheral ends of the release liner. That is, the outer peripheral edge of the pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet body is located away from the outer peripheral edges of the first and second release liners in the sheet surface direction at least in a part of the area. When the double-sided pressure-sensitive adhesive sheet body is composed of a single pressure-sensitive adhesive layer, for example, the outer peripheral edge of the pressure-sensitive adhesive layer has a concave shape at the outer peripheral edge of the sheet in the cross section in the thickness direction of the double-sided pressure-sensitive adhesive sheet. Has a region positioned away from the outer peripheral ends of the first and second release liners in the sheet plane direction. When the double-sided pressure-sensitive adhesive sheet body has a laminated structure including two pressure-sensitive adhesive layers forming both pressure-sensitive adhesive surfaces and a base material between the pressure-sensitive adhesive layers, for example, the outer peripheral edge of each pressure-sensitive adhesive layer has first and second peeling. It has the area | region located away from the outer peripheral edge of a liner in the sheet | seat surface direction. And the separation distance of the sheet | seat in-plane direction between the adhesive layer outer periphery end located in the sheet | seat surface outer direction from each release liner outer periphery end and each release liner outer periphery end is 5-2000 micrometers as above-mentioned. . When the release liner is peeled from the double-sided pressure-sensitive adhesive sheet, the outer peripheral edge of the pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet body is located away from the outer peripheral edges of the first and second release liners in the sheet surface direction. If a part (outer peripheral edge separation part) is used, it is easy to perform a peeling operation. Specifically, at the outer peripheral end separation part, for example, the operator's fingertip can be easily brought into contact with the first or second release liner to be peeled without being brought into contact with the adhesive layer, and thus the release liner to be peeled off. It is easy to start appropriate deformation for peeling in the release liner so that separation of both starts from the edge of the interface between the adhesive layer and the pressure-sensitive adhesive layer. Thus, in this double-sided pressure-sensitive adhesive sheet, it is easy to peel the release liner from the double-sided pressure-sensitive adhesive sheet body, for example, manually.

  In addition, at the outer peripheral edge separation portion of the double-sided pressure-sensitive adhesive sheet, as described above, when the release liner is peeled off, the operator's fingertip or the like is not brought into contact with the pressure-sensitive adhesive layer and touches the first or second release liner to be peeled off. Easy to touch. At the same time, at the outer peripheral edge separation part of the double-sided pressure-sensitive adhesive sheet, as described above, the separation in the release liner is started so that separation of both starts from the end of the interface between the release liner to be peeled off and the pressure-sensitive adhesive layer. It is easy to start an appropriate deformation for. In these double-sided pressure-sensitive adhesive sheets that can release the release liner using the outer peripheral edge separation part, respectively, a part of the double-sided pressure-sensitive adhesive sheet main body is pulled by the release liner when the release liner is peeled off. Therefore, it is suitable for suppressing the occurrence of partial breakage or loss on the pressure-sensitive adhesive surface or the pressure-sensitive adhesive layer.

  In addition, in the double-sided pressure-sensitive adhesive sheet, the separation distance in the sheet surface direction between the pressure-sensitive adhesive layer outer periphery edge and the release liner outer periphery edge located away from the release liner outer periphery edge in the sheet surface inner direction is It is 5-2000 micrometers like. This double-sided PSA sheet with such a configuration is suitable for efficient production. Specifically, it is as follows.

  First, a double-sided pressure-sensitive adhesive sheet raw material for producing this double-sided pressure-sensitive adhesive sheet through a process such as punching or cutting is prepared. This double-sided PSA sheet raw material has a pre-first release liner, a pre-second release liner, and at least one pressure-sensitive adhesive layer and is located between the pre-first and pre-second release liners. A laminated structure including a sheet body. Next, in a state where the double-sided PSA sheet raw material is subjected to pressure in the thickness direction, the double-sided PSA sheet raw material is processed so as to form a double-sided PSA sheet having the desired outer dimensions. In a state where the double-sided PSA sheet raw material is subjected to pressure in the thickness direction, the adhesive layer as an elastic body in the pre-double-sided PSA sheet body of the raw material can be elastically deformed according to the pressure, It can stretch elastically in the in-plane direction of the raw material at a corresponding elongation rate, and can be in a state of elastically bulging from between the pre-first release liner and the pre-second release liner at the outer peripheral end of the raw material. Examples of the processing means include punching and / or cutting. Specifically, in the processing step, a pressure is applied in the thickness direction so that part or all of the outer peripheral edge of the double-sided pressure-sensitive adhesive sheet is newly formed by processing to obtain a double-sided pressure-sensitive adhesive sheet having the desired outer dimensions. The double-sided PSA sheet raw material in the received state is subjected to processing such as punching and / or cutting. In the double-sided pressure-sensitive adhesive sheet obtained by releasing the pressure state, the pressure-sensitive adhesive layer returns from the elastically deformed state to the non-deformed state, and the first release liner and the first layer are formed at the outer peripheral edge of the double-sided pressure-sensitive adhesive sheet newly generated in the processing step. 2 Take the state retracted inward with the release liner. That is, in the manufactured double-sided PSA sheet, the outer peripheral edge of the pressure-sensitive adhesive layer has a region located inwardly in the sheet plane direction from the outer peripheral edge of each release liner. The separation distance between the outer peripheral edge of each release liner and the outer peripheral edge of the adhesive layer as a result of utilizing the elastic deformation of the adhesive layer and the subsequent shape recovery is within a relatively short range of 5 to 2000 μm. Tend to fit in. On the other hand, in order to manufacture a double-sided pressure-sensitive adhesive sheet with a release liner having a larger outer dimension than the double-sided pressure-sensitive adhesive body or the pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive body, for example, a release liner having the same outer dimensions as the double-sided pressure-sensitive adhesive sheet body. After manufacturing the double-sided pressure-sensitive adhesive sheet associated with both the pressure-sensitive adhesive surfaces, it is necessary to replace each release liner with a release liner having a larger outer dimension than that of the double-sided pressure-sensitive adhesive sheet main body. However, such a method is not efficient from the viewpoint of material cost and the number of processes. The double-sided pressure-sensitive adhesive sheet in which the separation distance in the sheet surface direction between the pressure-sensitive adhesive layer outer periphery edge and the release liner outer periphery edge is 5 to 2000 μm away from the release liner outer periphery edge in the sheet surface inward direction. It is suitable for efficient production through the above-described process using elastic deformation of the adhesive layer and subsequent shape recovery.

  As described above, the double-sided pressure-sensitive adhesive sheet according to the first aspect of the present invention facilitates the release operation of the release liner and is suitable for suppressing partial breakage or loss of the pressure-sensitive adhesive layer at the time of release of the release liner. Suitable for efficient production. In addition, the double-sided pressure-sensitive adhesive sheet having a separation distance between the outer peripheral edge of the pressure-sensitive adhesive layer and the outer peripheral edge of each release liner in the in-plane direction is 5 to 2000 μm. While realizing the dimensions required for the sheet main body, it is suitable for avoiding the outer dimension of the double-sided pressure-sensitive adhesive sheet, that is, the outer dimension of the release liner, greatly exceeding the dimension of the double-sided pressure-sensitive adhesive sheet body.

  In the first aspect of the present invention, preferably, the outer peripheral edge of the pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet body is inward from the outer peripheral edge of the first release liner and the outer peripheral edge of the second release liner in the sheet in-plane direction. The distance is 5 to 2000 μm. That is, the outer peripheral edge of the pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet main body is located at a distance of 5 to 2000 μm inward of the sheet with respect to the outermost peripheral edge closest to the first release liner, and the second release. The distance between the innermost edge of the liner and the innermost edge of the liner is 5 to 2000 μm.

  1st side surface of this invention WHEREIN: Preferably, the thickness of the adhesive layer of a double-sided adhesive sheet main body is 25 micrometers or more. Such a configuration is suitable for ensuring a separation distance of 5 μm or more between the outer peripheral end of each release liner and the outer peripheral end of the pressure-sensitive adhesive layer in the above-described outer peripheral end separation region.

In the first aspect of the present invention, preferably, the storage elastic modulus at 23 ° C. of the pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet main body is 1.0 × 10 ⁴ Pa or more. With such a configuration, for the double-sided pressure-sensitive adhesive sheet in which the separation distance between the outer peripheral edge of each release liner and the outer peripheral edge of the pressure-sensitive adhesive layer is 5 to 2000 μm, elastic deformation of the pressure-sensitive adhesive layer and subsequent shape recovery It is suitable for efficient production using.

  The double-sided pressure-sensitive adhesive sheet provided by the second aspect of the present invention includes a laminated structure including a first release liner, a second release liner, and a double-sided pressure-sensitive adhesive main body positioned between the first and second release liners. Have The double-sided pressure-sensitive adhesive sheet main body is, for example, a first pressure-sensitive adhesive layer on the first release liner side, a second pressure-sensitive adhesive layer on the second release liner side, and a substrate positioned between the first and second pressure-sensitive adhesive layers. A laminated structure including At least a part of the outer peripheral edge of the first pressure-sensitive adhesive layer is at a distance of 5 to 2000 μm inward from the outer peripheral edge of the first release liner and the outer peripheral edge of the second release liner in the in-plane direction. At least a part of the outer peripheral edge of the second pressure-sensitive adhesive layer is at a distance of 5 to 2000 μm inward from the outer peripheral edge of the first release liner and the outer peripheral edge of the second release liner in the in-plane direction. The sheet in-plane direction refers to the in-plane direction of the double-sided PSA sheet or the double-sided PSA sheet body. In such a sheet in-plane direction, at least a part of the outer peripheral edge of the first pressure-sensitive adhesive layer is at a distance of 5 to 2000 μm inward of the sheet with respect to the outer peripheral edge closest to the first release liner. Yes, and at a distance of 5 to 2000 μm inward of the sheet with respect to the outermost edge closest to the second release liner. At the same time, in the in-plane direction of the sheet, at least a part of the outer peripheral edge of the second pressure-sensitive adhesive layer is a distance of 5 to 2000 μm inward of the sheet with respect to the outer peripheral edge closest to the first release liner. And at a distance of 5 to 2000 μm inward of the sheet with respect to the outer peripheral edge closest to the second release liner.

  As described above, at least a part of the outer peripheral edge of each pressure-sensitive adhesive layer (first pressure-sensitive adhesive layer, second pressure-sensitive adhesive layer) of the double-sided pressure-sensitive adhesive sheet body in the double-sided pressure-sensitive adhesive sheet with a release liner is a sheet surface. In the inward direction, the distance is 5 to 2000 μm inward from the outer peripheral edge of the first release liner and the outer peripheral edge of the second release liner. That is, the outer peripheral edge of each pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet body is located away from the outer peripheral edges of the first and second release liners in the sheet surface direction at least in a part of the area. And the separation distance in the sheet surface direction between the first pressure-sensitive adhesive layer outer peripheral edge and each release liner outer peripheral edge located away from each release liner outer peripheral edge in the sheet surface inner direction, and from each release liner outer peripheral edge As described above, the separation distance in the sheet surface direction between the outer peripheral edge of the second pressure-sensitive adhesive layer and the outer peripheral edge of each release liner that are located apart in the sheet surface direction is 5 to 2000 μm as described above. When peeling the release liner from the double-sided pressure-sensitive adhesive sheet, the outer peripheral edge of the first pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet body is separated from the outer peripheral edges of the first and second release liners in the sheet surface direction. A part (second outer peripheral edge separation part) located or a part where the outer peripheral edge of the second adhesive layer is located away from the outer peripheral edge of the first and second release liners in the sheet surface direction (second outer peripheral edge separation part) ) Makes it easy to perform peeling work. Specifically, at the first outer peripheral edge separation site, for example, the operator's fingertip is on the first pressure-sensitive adhesive layer side without being brought into contact with the first pressure-sensitive adhesive layer, for example, on the first release liner to be peeled off Therefore, it is easy to start appropriate deformation for peeling in the first release liner so that separation of both starts from the edge of the interface between the first release liner and the first pressure-sensitive adhesive layer. In addition, at the second outer peripheral edge separation site, for example, the fingertip of the operator is not in contact with the second adhesive layer, but is in contact with the second release liner, for example, on the second adhesive layer side. Therefore, it is easy to start appropriate deformation for peeling in the second release liner so that separation of both starts from the edge of the interface between the second release liner and the second pressure-sensitive adhesive layer. Thus, in this double-sided pressure-sensitive adhesive sheet, it is easy to peel the release liner from the double-sided pressure-sensitive adhesive sheet body, for example, manually.

  Further, at each outer peripheral edge separation portion of the double-sided pressure-sensitive adhesive sheet, as described above, the operator's fingertip or the like is easily brought into contact with the release liner to be peeled without being brought into contact with the adhesive layer when the release liner is peeled off. At the same time, at each outer peripheral edge separation portion of the double-sided pressure-sensitive adhesive sheet, as described above, the peeling liner peels off from the edge of the interface between the peeling liner to be peeled off and the pressure-sensitive adhesive layer. Easy to start appropriate deformation for. In these double-sided pressure-sensitive adhesive sheets, each of which can be peeled off using the outer peripheral edge separation part, a part of the pressure-sensitive adhesive surface of the double-sided pressure-sensitive adhesive sheet body is pulled to the release liner when the release liner is peeled off. It is suitable for suppressing the occurrence of partial breakage or loss on the adhesive surface or the adhesive layer.

  In addition, in the double-sided pressure-sensitive adhesive sheet, the separation distance in the sheet surface direction between the first pressure-sensitive adhesive layer outer periphery edge and the release liner outer periphery edge located away from the release liner outer periphery edge in the sheet surface direction, And the separation distance in the sheet surface direction between the second pressure-sensitive adhesive layer outer periphery edge and the release liner outer periphery edge located away from each release liner outer periphery edge in the sheet surface inward direction is as described above. 5 to 2000 μm. This double-sided PSA sheet with such a configuration is suitable for efficient production. Specifically, it is as follows.

  First, a double-sided pressure-sensitive adhesive sheet raw material for producing this double-sided pressure-sensitive adhesive sheet through a process such as punching or cutting is prepared. This double-sided PSA sheet raw material has a laminated structure including a pre-first release liner, a pre-second release liner, and a pre-double-sided PSA sheet body positioned between the pre-first and pre-second release liners. The pre-double-sided pressure-sensitive adhesive sheet body is positioned between, for example, the first pressure-sensitive adhesive layer on the pre-first release liner side, the second pressure-sensitive adhesive layer on the pre-second release liner side, and the first and second pressure-sensitive adhesive layers. A laminated structure including a base material to be processed. Next, in a state where the double-sided PSA sheet raw material is subjected to pressure in the thickness direction, the double-sided PSA sheet raw material is processed so as to form a double-sided PSA sheet having the desired outer dimensions. In a state where the double-sided PSA sheet raw material is subjected to pressure in the thickness direction, each adhesive layer as an elastic body in the pre-double-sided PSA sheet body of the raw material can be elastically deformed according to the pressure, It stretches elastically in the in-plane direction of the raw material at an elongation ratio according to the elasticity, and is elastic from between the pre-first release liner or pre-second release liner and the base material of the pre-double-sided PSA sheet at the outer peripheral edge of the raw material. Can be in a bulging state. Examples of the processing means include punching and / or cutting. Specifically, in the processing step, a pressure is applied in the thickness direction so that part or all of the outer peripheral edge of the double-sided pressure-sensitive adhesive sheet is newly formed by processing to obtain a double-sided pressure-sensitive adhesive sheet having the desired outer dimensions. The double-sided PSA sheet raw material in the received state is subjected to processing such as punching and / or cutting. In the double-sided pressure-sensitive adhesive sheet obtained by releasing the pressure state, each pressure-sensitive adhesive layer returns from the elastically deformed state to the non-deformed state, and the first release liner or A state of retreating inward between the second release liner and the substrate is taken. That is, in the double-sided pressure-sensitive adhesive sheet to be manufactured, the first pressure-sensitive adhesive layer outer peripheral edge is located inwardly in the sheet surface inner direction from each release liner outer peripheral edge, and the second pressure-sensitive adhesive layer outer peripheral edge is It has the area | region located inward in the sheet surface inward direction from each peeling liner outer peripheral end. And each release liner outer periphery end and adhesive layer outer periphery end (the 1st adhesive layer outer periphery end, the 2nd adhesive layer outer periphery end) which arise as a result of utilizing the elastic deformation of the adhesive layer and subsequent shape recovery The separation distance between them tends to be within a relatively short range of 5 to 2000 μm. On the other hand, in order to manufacture a double-sided pressure-sensitive adhesive sheet with a release liner having a larger outer dimension than the double-sided pressure-sensitive adhesive body or the pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive body, for example, a release liner having the same outer dimensions as the double-sided pressure-sensitive adhesive sheet body. After manufacturing the double-sided pressure-sensitive adhesive sheet associated with both the pressure-sensitive adhesive surfaces, it is necessary to replace each release liner with a release liner having a larger outer dimension than that of the double-sided pressure-sensitive adhesive sheet main body. However, such a method is not efficient from the viewpoint of material cost and the number of processes. A separation distance in the sheet surface direction between the outer peripheral edge of the first pressure-sensitive adhesive layer and the outer peripheral edge of each release liner, which is located away from the outer peripheral edge of each release liner, and the sheet from the outer peripheral edge of each release liner The double-sided pressure-sensitive adhesive sheet in which the separation distance in the sheet surface direction between the outer peripheral edge of the second pressure-sensitive adhesive layer and the outer peripheral edge of each of the release liners located in the in-plane direction is 5 to 2000 μm is the pressure-sensitive adhesive layer. It is suitable for efficient production through the above-described process using elastic deformation and subsequent shape recovery.

  As described above, the double-sided pressure-sensitive adhesive sheet according to the second aspect of the present invention facilitates the release operation of the release liner and is suitable for suppressing partial breakage or loss of the pressure-sensitive adhesive layer at the time of release of the release liner. Suitable for efficient production. In addition, the separation distance between the outer peripheral edge of the first pressure-sensitive adhesive layer and the outer peripheral edge of each release liner located away from the outer peripheral edge of each release liner in the in-plane direction of the sheet, and the outer periphery of each release liner in the in-plane direction of the sheet The double-sided PSA sheet with a separation distance between the outer peripheral end of the second PSA layer and the outer peripheral end of each release liner, which is located away from the end, is 5 to 2000 μm, respectively, to achieve the dimensions required for the double-sided PSA sheet body However, it is suitable for avoiding that the outer dimension of the double-sided PSA sheet, that is, the outer dimension of the release liner, greatly exceeds the dimension of the double-sided PSA sheet body.

  In the second aspect of the present invention, preferably, the outer peripheral edge of the first pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet body is respectively the outer peripheral edge of the first release liner and the outer peripheral edge of the second release liner in the sheet in-plane direction. Inward from 5 to 2000 μm. That is, the outer peripheral edge of the first pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet body is located at a distance of 5 to 2000 μm inward of the sheet with respect to the outermost edge closest to the first release liner, and the first 2 The distance between the outer peripheral edge closest to the release liner is 5 to 2000 μm inward of the sheet.

  In the second aspect of the present invention, preferably, the outer peripheral edge of the second pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet body is each of the outer peripheral edge of the first release liner and the outer peripheral edge of the second release liner in the sheet in-plane direction. The distance is 5 to 2000 μm inward. That is, the outer peripheral edge of the second pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet body is located at a distance of 5 to 2000 μm inward of the sheet with respect to the outermost peripheral edge closest to the first release liner, and 2 The distance between the outer peripheral edge closest to the release liner is 5 to 2000 μm inward of the sheet.

  In the 2nd side surface of this invention, Preferably, the thickness of the 1st adhesive layer of a double-sided adhesive sheet main body is 25 micrometers or more. Such a configuration is suitable for securing the separation distance between each outer peripheral edge of the release liner and the outer peripheral edge of the first pressure-sensitive adhesive layer at 5 μm or more in the first outer peripheral edge separation portion. Preferably, the thickness of the 2nd adhesive layer of a double-sided adhesive sheet main body is 25 micrometers or more. Such a configuration is suitable for securing a separation distance between each outer peripheral edge of the release liner and the outer peripheral edge of the second pressure-sensitive adhesive layer at 5 μm or more in the above-described second outer peripheral edge separation region.

In the first aspect of the present invention, preferably, the storage elastic modulus at 23 ° C. of the first pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet main body is 1.0 × 10 ⁴ Pa or more. Such a structure is the elastic deformation of the first pressure-sensitive adhesive layer and the subsequent deformation of the double-sided pressure-sensitive adhesive sheet in which the above-mentioned separation distance between the outer peripheral edge of each release liner and the first pressure-sensitive adhesive layer is 5 to 2000 μm. This is suitable for efficient production using the shape recovery. Preferably, the storage elastic modulus at 23 ° C. of the second pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet main body is 1.0 × 10 ⁴ Pa or more. With such a configuration, for the double-sided pressure-sensitive adhesive sheet in which the above-mentioned separation distance between each outer peripheral edge of the release liner and the second pressure-sensitive adhesive layer is 5 to 2000 μm, elastic deformation of the second pressure-sensitive adhesive layer and thereafter This is suitable for efficient production using the shape recovery.

It is a fragmentary sectional view of the double-sided adhesive sheet concerning one embodiment of the present invention. It is a partial expanded sectional view of the double-sided adhesive sheet shown in FIG. It is a fragmentary sectional view of the double-sided adhesive sheet concerning one embodiment of the present invention. It is a partial expanded sectional view of the double-sided adhesive sheet shown in FIG.

  FIG. 1 is a partial cross-sectional view of an adhesive sheet X1 which is a double-sided adhesive sheet with a release liner according to an embodiment of the present invention. The pressure-sensitive adhesive sheet X1 has a laminated structure including a pressure-sensitive adhesive sheet body 10 which is a double-sided pressure-sensitive adhesive sheet body and release liners L1 and L2. The pressure-sensitive adhesive sheet body 10 is located between the release liners L <b> 1 and L <b> 2 and includes a pressure-sensitive adhesive layer 11. The pressure-sensitive adhesive sheet body 10 or the pressure-sensitive adhesive layer 11 has pressure-sensitive adhesive surfaces 11 ′ and 11 ′ that can be attached to an adherend, and has light transmittance in this embodiment. Such a pressure-sensitive adhesive sheet main body 10 is a double-sided pressure-sensitive adhesive sheet for optics that can be used in the manufacture of flat panel displays or the like, for example. A display device such as a liquid crystal display or an input device such as a touch panel has a laminated structure including various substrates and film bodies. As an optical double-sided pressure-sensitive adhesive sheet for joining predetermined parts adjacent to each other in the laminated structure. Alternatively, the pressure-sensitive adhesive sheet main body 10 can be used as an optical double-sided pressure-sensitive adhesive sheet for filling a gap between adjacent parts. The pressure-sensitive adhesive sheet X1 is a double-sided pressure-sensitive adhesive sheet with a release liner with release liners L1 and L2 for covering the pressure-sensitive adhesive surfaces 11 ′ and 11 ′ of such a pressure-sensitive adhesive sheet body 10.

  The pressure-sensitive adhesive sheet main body 10 or the pressure-sensitive adhesive layer 11 in the pressure-sensitive adhesive sheet X1 contains a pressure-sensitive adhesive as a main agent. The main agent is a component that occupies the largest weight ratio among the contained components. The pressure-sensitive adhesive layer 11 includes, for example, at least one selected from the group consisting of an acrylic polymer as an acrylic pressure-sensitive adhesive, polyurethane as a urethane pressure-sensitive adhesive, a silicone pressure-sensitive adhesive, and a rubber-based pressure-sensitive adhesive. From the viewpoint of realizing both the adhesive strength required for the pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet and high transparency, it is preferable to employ an acrylic polymer as the pressure-sensitive adhesive in the pressure-sensitive adhesive layer 11.

  When the pressure-sensitive adhesive layer 11 contains an acrylic polymer that is an acrylic pressure-sensitive adhesive, the acrylic polymer is preferably an acrylic acid alkyl ester having a linear or branched alkyl group, and / or a linear chain. The monomer unit derived from a methacrylic acid alkyl ester having a linear or branched alkyl group is contained as the main monomer unit having the largest weight ratio. Hereinafter, “(meth) acryl” means “acryl” and / or “methacryl”.

  (Meth) acrylic acid alkyl ester having a linear or branched alkyl group for forming a monomer unit of the acrylic polymer, that is, a linear chain contained in the monomer component for forming the acrylic polymer. Examples of the (meth) acrylic acid alkyl ester having a linear or branched alkyl group include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, N-butyl (meth) acrylate, s-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, isopentyl (meth) acrylate, (meta ) Hexyl acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (meth) acrylic Isooctyl acid, nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, undecyl (meth) acrylate, dodecyl (meth) acrylate, (meth) acrylic acid Tridecyl, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, octadecyl (meth) acrylate, isostearyl (meth) acrylate, (meth) acrylic acid Examples thereof include (meth) acrylic acid alkyl esters having a linear or branched alkyl group having 1 to 20 carbon atoms, such as nonadecyl and eicosyl (meth) acrylate. As the (meth) acrylic acid alkyl ester for the acrylic polymer, one kind of (meth) acrylic acid alkyl ester may be used, or two or more kinds of (meth) acrylic acid alkyl esters may be used. . In this embodiment, the (meth) acrylic acid alkyl ester for the acrylic polymer is preferably at least one selected from the group consisting of n-butyl acrylate, 2-ethylhexyl acrylate, and isostearyl acrylate. Is used.

  The proportion of the monomer unit derived from the (meth) acrylic acid alkyl ester having a linear or branched alkyl group in the acrylic polymer is preferably 50% by weight or more, more preferably 60% by weight or more, more preferably Is 70% by weight or more, more preferably 80% by weight or more, more preferably 90% by weight or more. That is, the proportion of the (meth) acrylic acid alkyl ester in the monomer component composition of the raw material for forming the acrylic polymer is preferably 50% by weight or more, more preferably 60% by weight or more, more preferably 70% by weight or more. More preferably, it is 80 weight% or more, More preferably, it is 90 weight% or more. The acrylic polymer has a monomer unit structure derived from the monomer component composition with such a (meth) acrylic acid alkyl ester ratio. The configuration relating to the proportion of the (meth) acrylic acid alkyl ester having a linear or branched alkyl group includes basic properties such as the tackiness of an acrylic polymer as an acrylic adhesive, and includes the acrylic polymer. This is suitable for properly expressing the pressure-sensitive adhesive layer 11 to be formed.

  The acrylic polymer contained in the pressure-sensitive adhesive layer 11 may include a monomer unit derived from an alicyclic monomer. Examples of the alicyclic monomer for forming the monomer unit of the acrylic polymer, i.e., the alicyclic monomer contained in the monomer component for forming the acrylic polymer, include (meth) acrylic acid cycloalkyl ester, (Meth) acrylic acid ester having a cyclic hydrocarbon ring, and (meth) acrylic acid ester having three or more hydrocarbon rings. Examples of the (meth) acrylic acid cycloalkyl ester include cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, cycloheptyl (meth) acrylate, and cyclooctyl (meth) acrylate. Examples of the (meth) acrylic acid ester having a bicyclic hydrocarbon ring include bornyl (meth) acrylate and isobornyl (meth) acrylate. Examples of (meth) acrylic acid esters having three or more hydrocarbon rings include, for example, (meth) acrylic acid dicyclopentanyl, (meth) acrylic acid dicyclopentanyloxyethyl, (meth) acrylic acid tricyclopenta Nyl, 1-adamantyl (meth) acrylate, 2-methyl-2-adamantyl (meth) acrylate, and 2-ethyl-2-adamantyl (meth) acrylate. As an alicyclic monomer for an acrylic polymer, one type of alicyclic monomer may be used, or two or more types of alicyclic monomers may be used. In the present embodiment, at least one selected from the group consisting of cyclohexyl acrylate, cyclohexyl methacrylate, isobornyl acrylate, and isobornyl methacrylate is preferably used as the alicyclic monomer for the acrylic polymer.

  The proportion of the monomer unit derived from the alicyclic monomer in the acrylic polymer is preferably 5 to 60 weights from the viewpoint of realizing appropriate flexibility in the pressure-sensitive adhesive layer 11 formed by including the acrylic polymer. %, More preferably 10 to 50% by weight, more preferably 12 to 40% by weight.

  The acrylic polymer contained in the pressure-sensitive adhesive layer 11 may include a monomer unit derived from a hydroxyl group-containing monomer. A hydroxyl group-containing monomer is a monomer that will have at least one hydroxyl group in the monomer unit. When the acrylic polymer in the pressure-sensitive adhesive layer 11 includes a hydroxyl group-containing monomer unit, it is easy to obtain adhesiveness and appropriate cohesive strength in the pressure-sensitive adhesive layer 11.

  Examples of the hydroxyl group-containing monomer for forming a monomer unit of the acrylic polymer, that is, the hydroxyl group-containing monomer contained in the monomer component for forming the acrylic polymer include, for example, a hydroxyl group-containing (meth) acrylic acid ester, vinyl alcohol , And allyl alcohol. Examples of the hydroxyl group-containing (meth) acrylic acid ester include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, and (meth) acrylic acid 4- Hydroxybutyl, 6-hydroxyhexyl (meth) acrylate, hydroxyoctyl (meth) acrylate, hydroxydecyl (meth) acrylate, hydroxylauryl (meth) acrylate, and (meth) acrylic acid (4-hydroxymethylcyclohexyl) And methyl. As the hydroxyl group-containing monomer for the acrylic polymer, one kind of hydroxyl group-containing monomer may be used, or two or more kinds of hydroxyl group-containing monomers may be used. In this embodiment, the hydroxyl group-containing monomer for the acrylic polymer is preferably 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, acrylic acid 4 At least one selected from the group consisting of -hydroxybutyl and 4-hydroxybutyl methacrylate is used.

  The proportion of the monomer unit derived from the hydroxyl group-containing monomer in the acrylic polymer is preferably 1% by weight or more, more preferably 2% by weight or more, more preferably 3% by weight or more, more preferably 7% by weight or more, more preferably Is 10% by weight or more, more preferably 15% by weight or more. The ratio of the monomer unit derived from the hydroxyl group-containing monomer in the acrylic polymer is preferably 35% by weight or less, more preferably 30% by weight or less. These configurations relating to the ratio of the hydroxyl group-containing monomer are suitable for realizing adhesiveness and appropriate cohesive force in the pressure-sensitive adhesive layer 11 formed by including the acrylic polymer.

  The acrylic polymer contained in the pressure-sensitive adhesive layer 11 may include a monomer unit derived from a nitrogen atom-containing monomer. A nitrogen atom-containing monomer is a monomer that will have at least one nitrogen atom in the monomer unit. When the acrylic polymer in the pressure-sensitive adhesive layer 11 includes a nitrogen atom-containing monomer unit, it is easy to obtain hardness and good adhesion reliability in the pressure-sensitive adhesive layer 11.

  Examples of the nitrogen atom-containing monomer for forming the monomer unit of the acrylic polymer, that is, the nitrogen atom-containing monomer contained in the monomer component for forming the acrylic polymer include N-vinyl cyclic amide and (meth) Examples include acrylamides. Examples of N-vinyl cyclic amides that are nitrogen atom-containing monomers include N-vinyl-2-pyrrolidone, N-vinyl-2-piperidone, N-vinyl-3-morpholinone, N-vinyl-2-caprolactam, and N-vinyl. -1,3-oxazin-2-one, and N-vinyl-3,5-morpholinedione. Examples of (meth) acrylamides that are nitrogen atom-containing monomers include (meth) acrylamide, N-ethyl (meth) acrylamide, N-isopropyl (meth) acrylamide, Nn-butyl (meth) acrylamide, N-octyl ( Mention may be made of (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N, N-dipropyl (meth) acrylamide and N, N-diisopropyl (meth) acrylamide. As the nitrogen atom-containing monomer for the acrylic polymer, one kind of nitrogen atom-containing monomer may be used, or two or more kinds of nitrogen atom-containing monomers may be used. In this embodiment, N-vinyl-2-pyrrolidone is preferably used as the nitrogen atom-containing monomer for the acrylic polymer.

  The proportion of the monomer unit derived from the nitrogen atom-containing monomer in the acrylic polymer is from the viewpoint of realizing appropriate hardness, adhesiveness, and transparency in the pressure-sensitive adhesive layer 11 formed including the acrylic polymer. , Preferably 1% by weight or more, more preferably 3% by weight or more, more preferably 5% by weight or more. Moreover, the ratio of the monomer unit derived from the nitrogen atom-containing monomer in the acrylic polymer is too hard in view of realizing sufficient transparency in the pressure-sensitive adhesive layer 11 formed by including the acrylic polymer. From the viewpoint of suppressing this and realizing good adhesion reliability, it is preferably 30% by weight or less, more preferably 25% by weight or less.

  The acrylic polymer contained in the pressure-sensitive adhesive layer 11 may include a monomer unit derived from a carboxy group-containing monomer. The carboxy group-containing monomer is a monomer that has at least one carboxy group in the monomer unit. When the acrylic polymer in the pressure-sensitive adhesive layer 11 includes a carboxy group-containing monomer unit, good adhesive reliability may be obtained in the pressure-sensitive adhesive layer 11.

  Examples of the carboxy group-containing monomer for forming the monomer unit of the acrylic polymer, that is, the carboxy group-containing monomer contained in the monomer component for forming the acrylic polymer include, for example, (meth) acrylic acid, itaconic acid, Mention may be made of maleic acid, fumaric acid, crotonic acid and isocrotonic acid. As the carboxy group-containing monomer for the acrylic polymer, one kind of carboxy group-containing monomer may be used, or two or more kinds of carboxy group-containing monomers may be used. In this embodiment, acrylic acid is preferably used as the carboxy group-containing monomer for the acrylic polymer.

  The ratio of the monomer unit derived from the carboxy group-containing monomer in the acrylic polymer is the same as that of the polar group when the polar group is present on the adherend surface in the pressure-sensitive adhesive layer 11 formed by including the acrylic polymer. From the viewpoint of obtaining good contribution reliability by obtaining the contribution of the interaction of the carboxy group, it is preferably 0.1% by weight or more, more preferably 0.5% by weight or more. Moreover, the ratio of the monomer unit derived from the carboxy group-containing monomer in the acrylic polymer described above realizes good adhesion reliability by suppressing the adhesive layer 11 formed including the acrylic polymer from becoming too hard. From the viewpoint of achieving the above, it is preferably 20% by weight or less, more preferably 15% by weight or less.

  The acrylic polymer contained in the pressure-sensitive adhesive layer 11 may have a crosslinked structure derived from a polyfunctional (meth) acrylate that is a copolymerizable crosslinking agent. Examples of polyfunctional (meth) acrylates include 1,6-hexanediol di (meth) acrylate, butanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, and (poly) propylene glycol di (meth) acrylate. ) Acrylate, neopentyl glycol di (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylol methanetri (Meth) acrylate, allyl (meth) acrylate, and vinyl (meth) acrylate. As the polyfunctional (meth) acrylate for the acrylic polymer, one kind of polyfunctional (meth) acrylate may be used, or two or more kinds of polyfunctional (meth) acrylates may be used. In this embodiment, the polyfunctional (meth) acrylate for the acrylic polymer is preferably selected from the group consisting of 1,6-hexanediol diacrylate, dipentaerythritol hexaacrylate, and trimethylolpropane triacrylate. At least one kind is used.

  The proportion of the monomer unit derived from polyfunctional (meth) acrylate in the acrylic polymer is preferably 0.01% by weight or more, more preferably 0.03% by weight or more, more preferably 0.05% by weight or more, more Preferably it is 0.1 weight% or more. The ratio of the monomer unit derived from polyfunctional (meth) acrylate in the acrylic polymer is preferably 1% by weight or less, more preferably 0.5% by weight or less. These configurations relating to the ratio of the polyfunctional (meth) acrylate are suitable for achieving appropriate hardness and adhesiveness in the pressure-sensitive adhesive layer 11 formed by including the acrylic polymer.

  When the adhesive layer 11 contains the above acrylic polymer as an adhesive, the content rate of the said acrylic polymer in the adhesive layer 11 is 85 to 100 weight%, for example.

  The pressure-sensitive adhesive layer 11 may contain, for example, an acrylic oligomer having a raw material monomer composition different from that of the above-mentioned acrylic polymer from the viewpoint of realizing high adhesiveness at room temperature. When the pressure-sensitive adhesive layer 11 contains such an acrylic oligomer, the content of the acrylic oligomer in the pressure-sensitive adhesive layer 11 is, for example, 0 with respect to 100 parts by weight of the pressure-sensitive adhesive or acrylic polymer in the pressure-sensitive adhesive layer 11. 0.1 to 20 parts by weight.

  The oligomer is preferably a (meth) acrylic monomer unit derived from a (meth) acrylic acid ester having a cyclic structure (ring-containing (meth) acrylic acid ester) and a linear or branched alkyl group. And a monomer unit derived from an acid alkyl ester.

  The ring-containing (meth) acrylic acid ester for forming the monomer unit of the oligomer, that is, the ring-containing (meth) acrylic acid ester contained in the monomer component for forming the oligomer includes, for example, (meth) acrylic acid Examples include cycloalkyl esters, (meth) acrylic acid esters having a bicyclic hydrocarbon ring, (meth) acrylic acid esters having three or more hydrocarbon rings, and (meth) acrylic acid esters having an aromatic ring. It is done. Examples of the (meth) acrylic acid cycloalkyl ester include cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, cycloheptyl (meth) acrylate, and cyclooctyl (meth) acrylate. Examples of the (meth) acrylic acid ester having a bicyclic hydrocarbon ring include bornyl (meth) acrylate and isobornyl (meth) acrylate. Examples of (meth) acrylic acid esters having three or more hydrocarbon rings include, for example, (meth) acrylic acid dicyclopentanyl, (meth) acrylic acid dicyclopentanyloxyethyl, (meth) acrylic acid tricyclopenta Nyl, 1-adamantyl (meth) acrylate, 2-methyl-2-adamantyl (meth) acrylate, and 2-ethyl-2-adamantyl (meth) acrylate. Examples of the (meth) acrylic acid ester having an aromatic ring include phenyl (meth) acrylate, phenoxyethyl (meth) acrylate, and benzyl (meth) acrylate. As the ring-containing (meth) acrylic acid ester for the oligomer, one kind of ring-containing (meth) acrylic acid ester may be used, or two or more kinds of ring-containing (meth) acrylic acid esters may be used. . In the present embodiment, at least one selected from the group consisting of dicyclopentanyl acrylate and dicyclopentanyl methacrylate is preferably used as the ring-containing (meth) acrylic acid ester for the oligomer.

  The proportion of the monomer unit derived from the ring-containing (meth) acrylic acid ester in the oligomer is preferably 10 to 90 wt. %, More preferably 20 to 80% by weight, more preferably 35 to 75% by weight.

  (Meth) acrylic acid alkyl ester having a linear or branched alkyl group for forming a monomer unit of the oligomer, that is, linear or branched, contained in the monomer component for forming the oligomer Examples of (meth) acrylic acid alkyl esters having a chain alkyl group include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, (meth) N-butyl acrylate, s-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, isopentyl (meth) acrylate, (meth) acrylic acid Hexyl, heptyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate Nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, undecyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate, Tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, octadecyl (meth) acrylate, isostearyl (meth) acrylate, nonadecyl (meth) acrylate, And (meth) acrylic acid alkyl ester having a linear or branched alkyl group having 1 to 20 carbon atoms, such as eicosyl (meth) acrylate. As the (meth) acrylic acid alkyl ester for the oligomer, one type of (meth) acrylic acid alkyl ester may be used, or two or more types of (meth) acrylic acid alkyl ester may be used. In this embodiment, methyl methacrylate is preferably used as the (meth) acrylic acid alkyl ester for the oligomer.

  The proportion of monomer units derived from (meth) acrylic acid alkyl ester having a linear or branched alkyl group in the above oligomer realizes an appropriate elastic modulus in the pressure-sensitive adhesive layer 11 formed including the oligomer. From the viewpoint of achieving the above, it is preferably 10 to 90% by weight, more preferably 15 to 80% by weight, and more preferably 20 to 60% by weight.

  The oligomer is derived from a carboxy group-containing monomer, an amide group-containing monomer, an amino group-containing monomer, a cyano group-containing monomer, a sulfonic acid group-containing monomer, a phosphoric acid group-containing monomer, an isocyanate group-containing monomer, or an imide group-containing monomer. It may contain a monomer unit.

  The weight average molecular weight (Mw) of the oligomer is, for example, 1000 to 30000, preferably 1000 to 20000, and more preferably 1500 to 10,000. From the viewpoint of ensuring a good adhesive force in the pressure-sensitive adhesive layer 11 formed including the oligomer, the oligomer preferably has a weight average molecular weight of 1000 or more. On the other hand, it is preferable that the weight average molecular weight of the oligomer is 30000 or less from the viewpoint of ensuring the adhesive strength at room temperature in the pressure-sensitive adhesive layer 11 formed including the oligomer.

The weight average molecular weight of the oligomer can be measured by a gel permeation chromatograph (GPC) method. For example, the weight average molecular weight (Mw) can be determined as a standard polystyrene equivalent value under the following measurement conditions using a GPC measuring device (trade name “HLC-8120GPC”, manufactured by Tosoh Corporation).
Column: TSKgel SuperAWM-H (upstream, manufactured by Tosoh Corporation), TSKgel SuperAW4000 (manufactured by Tosoh Corporation) and TSKgel SuperAW2500 (downstream, manufactured by Tosoh Corporation) are connected in series. Column size: 6 for each column 0.0mmφ × 150mm
Column temperature (measurement temperature): 40 ° C
・ Eluent: Tetrahydrofuran (THF)
・ Flow rate: 0.4 mL / min ・ Sample injection volume: 20 μL
Sample concentration: about 2.0 g / L (tetrahydrofuran solution)
Standard sample: Polystyrene Detector: Differential refractometer (RI)

  The pressure-sensitive adhesive layer 11 may contain a silane coupling agent. Examples of the silane coupling agent include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-aminopropyltrimethoxysilane, and N-phenyl-aminopropyltrimethoxysilane. . Examples of the silane coupling agent include commercial products such as trade name “KBM-403” (manufactured by Shin-Etsu Chemical Co., Ltd.). As the silane coupling agent, γ-glycidoxypropyltrimethoxysilane is preferable.

  When the pressure-sensitive adhesive layer 11 contains a silane coupling agent, the content of the silane coupling agent in the pressure-sensitive adhesive layer 11 is preferably 0 with respect to 100 parts by weight of the pressure-sensitive adhesive or acrylic polymer in the pressure-sensitive adhesive layer 11. 0.01 parts by weight or more, more preferably 0.02 parts by weight or more. The content of the silane coupling agent in the pressure-sensitive adhesive layer 11 is preferably 1 part by weight or less, more preferably 0.5 parts by weight or less, with respect to 100 parts by weight of the acrylic polymer. The said structure regarding content of a silane coupling agent is in the adhesive layer 11 formed including the said silane coupling agent, when implement | achieving the high adhesiveness in humidification conditions, especially the high adhesiveness with respect to glass. Is preferred.

  The pressure-sensitive adhesive layer 11 may contain an ultraviolet absorber. The ultraviolet absorber is a chemical species that can efficiently absorb ultraviolet rays and can convert the absorbed energy into heat, infrared rays, or the like and release it. Examples of such UV absorbers include benzotriazole UV absorbers, hydroxyphenyl triazine UV absorbers, salicylic acid ester UV absorbers, benzophenone UV absorbers, oxybenzophenone UV absorbers, and cyanoacrylates. An ultraviolet absorber is mentioned. The pressure-sensitive adhesive layer 11 may contain one type of ultraviolet absorber, or may contain two or more types of ultraviolet absorbers.

  Examples of the benzotriazole ultraviolet absorber include 2- (2-hydroxy-5-tert-butylphenyl) -2H-benzotriazole (trade name “TINUVIN PS”, manufactured by BASF), benzenepropanoic acid 3- (2H -Benzotriazol-2-yl) -5- (1,1-dimethylethyl) -4-hydroxy alkyl ester having 7 to 9 carbon atoms (trade name “TINUVIN 384-2”, manufactured by BASF), octyl 3- [3-tert-butyl-4-hydroxy-5- (5-chloro-2H-benzotriazol-2-yl) phenyl] propionate and 2-ethylhexyl-3- [3-tert-butyl-4-hydroxy-5- Mixture of (5-chloro-2H-benzotriazol-2-yl) phenyl] propionate (trade name “TINUVIN 109”, manufactured by BASF), 2- (2H-benzotriazol-2-yl) -4,6-bis ( 1-Methyl-1-phenylethyl) phenol (trade name “TI NUVIN 900 ", manufactured by BASF), 2- (2H-benzotriazol-2-yl) -6- (1-methyl-1-phenylethyl) -4- (1,1,3,3-tetramethylbutyl) Reaction of phenol (trade name “TINUVIN 928”, manufactured by BASF), methyl 3- (3- (2H-benzotriazol-2-yl) -5-tert-butyl-4-hydroxyphenyl) propionate and polyethylene glycol 300 Product (trade name “TINUVIN 1130”, manufactured by BASF), 2- (2H-benzotriazol-2-yl) -p-cresol (trade name “TINUVIN P”, manufactured by BASF), 2- (2H-benzotriazole -2-yl) -4,6-bis (1-methyl-1-phenylethyl) phenol (trade name “TINUVIN 234”, manufactured by BASF), 2- [5-chloro-2H-benzotriazol-2-yl ] -4-Methyl-6- (tert-butyl) phenol (trade name “TINUVIN 326”, manufactured by BASF), 2- (2H -Benzotriazol-2-yl) -4,6-di-tert-pentylphenol (trade name “TINUVIN 328”, manufactured by BASF), 2- (2H-benzotriazol-2-yl) -4- (1, 1,3,3-tetramethylbutyl) phenol (trade name “TINUVIN 329”, manufactured by BASF), 2,2′-methylenebis [6- (2H-benzotriazol-2-yl) -4- (1,1 , 3,3-tetramethylbutyl) phenol] (trade name “TINUVIN 360”, manufactured by BASF), 2- (2H-benzotriazol-2-yl) -6-dodecyl-4-methylphenol (trade name “TINUVIN”) 571 ”(manufactured by BASF), 2- [2-hydroxy-3- (3,4,5,6-tetrahydrophthalimido-methyl) -5-methylphenyl] benzotriazole (trade name“ Sumisorb 250 ”, Sumitomo Chemical Co., Ltd.) Made by the company), and 2,2′-methylenebis [6- (2H-benzotriazol-2-yl) -4-tert-octylpheno Le] (trade name "ADK STAB LA-31", Ltd. ADEKA), and the like.

  Examples of the hydroxyphenyl triazine-based ultraviolet absorber include 2- (4,6-bis (2,4-dimethylphenyl) -1,3,5-triazin-2-yl) -5-hydroxyphenyl and [(carbon Reaction product with several 10 to 16 alkyloxy) methyl] oxirane (trade name “TINUVIN 400”, manufactured by BASF), 2- [4,6-bis (2,4-dimethylphenyl) -1,3, 5-Triazin-2-yl] -5- [3- (dodecyloxy) -2-hydroxypropoxy] phenol), 2- (2,4-dihydroxyphenyl) -4,6-bis- (2,4-dimethyl) Reaction product of (phenyl) -1,3,5-triazine and (2-ethylhexyl) -glycidic acid ester (trade name “TINUVIN 405”, manufactured by BASF), 2,4-bis (2-hydroxy-4- Butoxyphenyl) -6- (2,4-dibutoxyphenyl) -1,3,5-triazine (trade name “TINUVIN 460”, manufactured by BASF) -(4,6-Diphenyl-1,3,5-triazin-2-yl) -5-[(hexyl) oxy] -phenol (trade name “TINUVIN 1577”, manufactured by BASF), 2- (4,6 -Diphenyl-1,3,5-triazin-2-yl) -5- [2- (2-ethylhexanoyloxy) ethoxy] -phenol (trade name “ADK STAB LA-46”, manufactured by ADEKA Corporation), and 2- (2-Hydroxy-4- [1-octyloxycarbonylethoxy] phenyl) -4,6-bis (4-phenylphenyl) -1,3,5-triazine (trade name “TINUVIN 479”, manufactured by BASF ).

  Examples of salicylic acid ester UV absorbers include phenyl 2-acryloyloxybenzoate, phenyl 2-acryloyloxy-3-methylbenzoate, phenyl 2-acryloyloxy-4-methylbenzoate, phenyl 2-acryloyloxy-5-methylbenzoate. , Phenyl 2-acryloyloxy-3-methoxybenzoate, phenyl 2-hydroxybenzoate, phenyl 2-hydroxy-3-methylbenzoate, phenyl 2-hydroxy-4-methylbenzoate, phenyl 2-hydroxy-5-methylbenzoate, phenyl 2 -Hydroxy-3-methoxybenzoate and 2,4-di-tert-butylphenyl 3,5-di-tert-butyl-4-hydroxybenzoate (trade name “TINUVIN 120”, manufactured by BASF).

  Examples of the benzophenone ultraviolet absorber and oxybenzophenone ultraviolet absorber include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid, and 2-hydroxy. -4-Octyloxybenzophenone, 4-dodecyloxy-2-hydroxybenzophenone, 4-benzyloxy-2-hydroxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone (trade name “KEMISORB 111”, Chemipro Kasei Co., Ltd. 2,2 ′, 4,4′-tetrahydroxybenzophenone (trade name “SEESORB 106”, manufactured by Cypro Kasei Co., Ltd.), and 2,2′-dihydroxy-4,4′-dimethoxybenzophenone.

  Examples of the cyanoacrylate ultraviolet absorber include alkyl 2-cyanoacrylate, cycloalkyl 2-cyanoacrylate, alkoxyalkyl 2-cyanoacrylate, alkenyl 2-cyanoacrylate, and alkynyl 2-cyanoacrylate.

  The ultraviolet absorber contained in the pressure-sensitive adhesive layer 11 is preferably benzotriazole from the viewpoint of having high ultraviolet absorption and high light stability, and from the viewpoint of easily obtaining a highly transparent pressure-sensitive adhesive layer 11. It is at least one selected from the group consisting of a UV absorber, a hydroxyphenyltriazine UV absorber, and a benzophenone UV absorber. The ultraviolet absorber contained in the pressure-sensitive adhesive layer 11 is more preferably a benzotriazole in which a phenyl group having a hydrocarbon group having 6 or more carbon atoms and a hydroxyl group as a substituent is bonded to a nitrogen atom constituting the benzotriazole ring UV absorber.

  When the pressure-sensitive adhesive layer 11 contains an ultraviolet absorber, the content of the ultraviolet absorber in the pressure-sensitive adhesive layer 11 controls the transmittance of light having a wavelength of 350 nm in the pressure-sensitive adhesive layer 11 to realize high ultraviolet absorption. From this viewpoint, it is preferably 0.01 parts by weight or more, more preferably 0.05 parts by weight or more, more preferably 0.1 parts by weight or more with respect to 100 parts by weight of the pressure-sensitive adhesive or acrylic polymer in the pressure-sensitive adhesive layer 11. It is. Moreover, the content of the ultraviolet absorber in the pressure-sensitive adhesive layer 11 suppresses the occurrence of yellowing phenomenon of the pressure-sensitive adhesive accompanying the addition of the ultraviolet absorber in the pressure-sensitive adhesive layer 11 and realizes excellent optical characteristics and high transparency. From the viewpoint of, the amount is preferably 10 parts by weight or less, more preferably 9 parts by weight or less, more preferably 8 parts by weight or less with respect to 100 parts by weight of the pressure-sensitive adhesive or acrylic polymer in the pressure-sensitive adhesive layer 11.

  The pressure-sensitive adhesive layer 11 may contain a light stabilizer. When the pressure-sensitive adhesive layer 11 contains a light stabilizer, it preferably contains a UV absorber. A light stabilizer is a chemical species that can trap radicals that can be generated by irradiation with light such as ultraviolet rays. Examples of the light stabilizer include amine light stabilizers such as phenol light stabilizers, phosphorus light stabilizers, thioether light stabilizers, and hindered amine light stabilizers. The pressure-sensitive adhesive layer 11 may contain one type of light stabilizer, or may contain two or more types of light stabilizer.

  Examples of phenolic light stabilizers include 2,6-di-tert-butyl-4-methylphenol, 4-hydroxymethyl-2,6-di-tert-butylphenol, and 2,6-di-tert-butyl- 4-ethylphenol, butylated hydroxyanisole, n-octadecyl 3- (4-hydroxy-3,5-di-tert-butylphenyl) propionate, distearyl (4-hydroxy-3-methyl-5-tert-butyl) Benzyl malonate, tocopherol, 2,2'-methylenebis (4-methyl-6-tert-butylphenol), 2,2'-methylenebis (4-ethyl-6-tert-butylphenol), 4,4'-methylenebis (2 , 6-di-tert-butylphenol), 4,4′-butylidenebis (6-tert-butyl-m-cresol), 4,4′-thiobis (6-tert-butyl-m-cresol), styrenated phenol, N, N'-hexamethylenebis (3,5-di-tert-butyl-4- Roxyhydrocinnamide, bis (3,5-di-tert-butyl-4-hydroxybenzylphosphonic acid ethyl ester) calcium, 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) ) Butane, 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, tetrakis [3- (3,5-di-tert-butyl) -4-hydroxyphenyl) propionyloxymethyl] methane, 1,6-hexanediol-bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 2,2′-methylenebis (4 -Methyl-6-cyclohexylphenol), 2,2'-methylenebis [6- (1-methylcyclohexyl) -p-cresol], 1,3,5-tris (4-tert-butyl-3-hydroxy-2, 6-dimethylbenzyl) isocyanuric acid, 1,3,5-tris (3,5-di-tert-butyl-4-hydroxy) Cybenzyl) isocyanuric acid, triethylene glycol-bis [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate], 2,2′-oxamidobis [ethyl 3- (3,5-di-tert -Butyl-4-hydroxyphenyl) propionate], 6- (4-hydroxy-3,5-di-tert-butylanilino) -2,4-dioctylthio-1,3,5-triazine, bis [2-tert- Butyl-4-methyl-6- (2-hydroxy-3-tert-butyl-5-methylbenzyl) phenyl] terephthalate, 3,9-bis {2- [3- (3-tert-butyl-4-hydroxy- 5-methylphenyl) propionyloxy] -1,1-dimethylethyl} -2,4,8,10-tetraoxaspiro [5.5] undecane, and 3,9-bis {2- [3- (3, 5-Di-tert-butyl-4-hydroxyphenyl) propionyloxy] -1,1-dimethylethyl} -2,4,8,10-tetraoxa Pirro [5.5], and undecane.

  Examples of phosphorous light stabilizers include trisnonylphenyl phosphite, tris (2,4-di-tert-butylphenyl) phosphite, tris [2-tert-butyl-4- (3-tert-butyl-4). -Hydroxy-5-methylphenylthio) -5-methylphenyl] phosphite, tridecyl phosphite, octyl diphenyl phosphite, di (decyl) monophenyl phosphite, di (tridecyl) pentaerythritol diphosphite, distearyl penta Erythritol diphosphite, di (nonylphenyl) pentaerythritol diphosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis (2,6-di-tert-butyl-4-methyl) Phenyl) pentaerythritol diphosphite, bis (2,4,6-tri-tert-butylphenyl) pentaerythritol diphosphite Tetra (tridecyl) isopropylidenediphenol diphosphite, tetra (tridecyl) -4,4'-n-butylidenebis (2-tert-butyl-5-methylphenol) diphosphite, hexa (tridecyl) -1,1, 3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butanetriphosphite, tetrakis (2,4-di-tert-butylphenyl) biphenylene diphosphonite, 9,10-dihydro-9-oxa -10-phosphaphenanthrene-10-oxide and tris (2-[(2,4,8,10-tetrakis-tert-butyldibenzo [d, f] [1,3,2] dioxaphosphine Pin-6-yl) oxy] ethyl) amine.

  Examples of the thioether-based light stabilizer include dialkylthiodipropionate compounds such as dilauryl thiodipropionate, dimyristyl thiodipropionate, and distearyl thiodipropionate, and tetrakis [methylene (3-dodecylthio) propionate]. Examples thereof include β-alkyl mercaptopropionic acid ester compounds of polyols such as methane.

  Examples of the amine light stabilizer include a polymer of dimethyl succinate and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol (trade name “TINUVIN 622”, manufactured by BASF), The polymer and N, N ′, N ″, N ′ ″-tetrakis- (4,6-bis- (butyl- (N-methyl-2,2,6,6-tetramethylpiperidin-4-yl) ) Amino) -triazin-2-yl) -4,7-diazadecane-1,10-diamine reaction product (trade name “TINUVIN 119”, manufactured by BASF), poly [{6- (1 , 1,3,3-tetramethylbutyl) amino-1,3,5-triazine-2--4-diyl} {(2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene {( 2,2,6,6-tetramethyl-4-piperidyl) imino}] (trade name “TINUVIN 944”, manufactured by BASF), bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate ( Product name `` TINUVIN 770 , Produced by BASF), bis (2,2,6,6-tetramethyl-1- (octyloxy) -4-piperidinyl) ester, 1,1-dimethylethyl hydroperoxide and octane produced from decanedioic acid Product (trade name “TINUVIN 123”, manufactured by BASF), bis (1,2,2,6,6-pentamethyl-4-piperidyl) [[3,5-bis (1,1-dimethylethyl) -4- Hydroxyphenyl] methyl] butyl malonate (trade name “TINUVIN 144”, manufactured by BASF), cyclohexane and N-butyl peroxide 2,2,6,6-tetramethyl-4-piperidineamine-2,4,6- Reaction product of trichloro-1,3,5-triazine and 2-aminoethanol (trade name “TINUVIN 152”, manufactured by BASF), bis (1,2,2,6,6-pentamethyl- 4-piperidyl) sebacate and methyl 1,2,2,6,6-pentamethyl-4-piperidylsebake And a mixture of 1, 2, 3, 4-butanetetracarboxylic acid and 1, 2, 2, 6, 6-pentamethyl-4-piperidinol and 3, 9-Bis (2-hydroxy-1,1-dimethylethyl) -2,4,8,10-tetraoxaspiro [5.5] undecane mixed ester (trade name “ADK STAB LA-63P”, Inc. ADEKA). As the amine stabilizer, a hindered amine stabilizer is particularly preferable.

  When the pressure-sensitive adhesive layer 11 contains a light stabilizer, the content of the light stabilizer in the pressure-sensitive adhesive layer 11 is a pressure-sensitive adhesive in the pressure-sensitive adhesive layer 11 from the viewpoint of realizing sufficient light resistance in the pressure-sensitive adhesive layer 11. The amount is preferably at least 0.1 part by weight, more preferably at least 0.2 part by weight, based on 100 parts by weight of the agent or acrylic polymer. In addition, the content of the light stabilizer in the pressure-sensitive adhesive layer 11 is that the pressure-sensitive adhesive in the pressure-sensitive adhesive layer 11 realizes high transparency by suppressing coloring due to the light stabilizer in the pressure-sensitive adhesive layer 11. The amount is preferably 5 parts by weight or less, more preferably 3 parts by weight or less based on 100 parts by weight of the acrylic polymer.

  The pressure-sensitive adhesive or acrylic polymer contained in the pressure-sensitive adhesive layer 11 may be crosslinked with a crosslinking agent that is not the above-mentioned copolymerizable crosslinking agent. It is possible to adjust the gel fraction of the pressure-sensitive adhesive layer 11 by utilizing the crosslinking of the pressure-sensitive adhesive or acrylic polymer by the crosslinking agent. Examples of such crosslinking agents include isocyanate crosslinking agents, epoxy crosslinking agents, melamine crosslinking agents, peroxide crosslinking agents, urea crosslinking agents, metal alkoxide crosslinking agents, metal chelate crosslinking agents, metals Examples include salt-based crosslinking agents, carbodiimide-based crosslinking agents, oxazoline-based crosslinking agents, aziridine-based crosslinking agents, and amine-based crosslinking agents. The pressure-sensitive adhesive layer 11 may contain one type of the cross-linking agent or may contain two or more types of the cross-linking agent. In the present embodiment, at least one selected from the group consisting of an isocyanate-based crosslinking agent and an epoxy-based crosslinking agent is preferably used.

  Examples of the isocyanate-based crosslinking agent include lower aliphatic polyisocyanates, alicyclic polyisocyanates, and aromatic polyisocyanates. Examples of lower aliphatic polyisocyanates include 1,2-ethylene diisocyanate, 1,4-butylene diisocyanate, and 1,6-hexamethylene diisocyanate. Examples of the alicyclic polyisocyanates include cyclopentylene diisocyanate, cyclohexylene diisocyanate, isophorone diisocyanate, hydrogenated tolylene diisocyanate, and hydrogenated xylene diisocyanate. Aromatic polyisocyanates include, for example, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4′-diphenylmethane diisocyanate, and xylylene diisocyanate. In addition, as an isocyanate-based crosslinking agent, trimethylolpropane / tolylene diisocyanate adduct (trade name “Coronate L”, manufactured by Nippon Polyurethane Industry Co., Ltd.), trimethylolpropane / hexamethylene diisocyanate adduct (trade name “Coronate HL”) And commercial products such as trimethylolpropane / xylylene diisocyanate adduct (trade name “Takenate D-110N”, manufactured by Mitsui Chemicals, Inc.).

  Examples of the epoxy crosslinking agent (polyfunctional epoxy compound) include N, N, N ′, N′-tetraglycidyl-m-xylenediamine, diglycidylaniline, and 1,3-bis (N, N-diglycidylamino). Methyl) cyclohexane, 1,6-hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, sorbitol polyglycidyl ether, Glycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, polyglycerol polyglycidyl ether, sorbitan polyglycidyl ether, trimethylolpropane polyglycid Examples include dil ether, adipic acid diglycidyl ester, o-phthalic acid diglycidyl ester, triglycidyl-tris (2-hydroxyethyl) isocyanurate, resorcin diglycidyl ether, and bisphenol-S-diglycidyl ether. Moreover, as an epoxy-type crosslinking agent, the epoxy-type resin which has two or more epoxy groups is also mentioned. In addition, examples of the epoxy-based crosslinking agent include commercial products such as a trade name “Tetrad C” (manufactured by Mitsubishi Gas Chemical Company, Inc.).

  When the pressure-sensitive adhesive layer 11 contains the above crosslinking agent for crosslinking between acrylic polymers, the content of the crosslinking agent in the pressure-sensitive adhesive layer 11 is sufficient for the adherend in the pressure-sensitive adhesive layer 11. From the viewpoint of realizing the adhesion reliability, the amount is preferably 0.001 part by weight or more, more preferably 0.01 part by weight or more with respect to 100 parts by weight of the pressure-sensitive adhesive or acrylic polymer in the pressure-sensitive adhesive layer 11. In addition, the content of the cross-linking agent in the pressure-sensitive adhesive layer 11 is suitable for the pressure-sensitive adhesive or acrylic in the pressure-sensitive adhesive layer 11 from the viewpoint of realizing an appropriate flexibility in the pressure-sensitive adhesive layer 11 and realizing a good pressure-sensitive adhesive force. The amount is preferably 10 parts by weight or less, more preferably 5 parts by weight or less, based on 100 parts by weight of the polymer.

  The pressure-sensitive adhesive layer 11 is optionally formed by a crosslinking accelerator, a tackifier resin, an anti-aging agent, a filler, a colorant such as a pigment or a dye, an antioxidant, a chain transfer agent, a plasticizer, a softening agent, or a surfactant. An additive such as an agent and an antistatic agent may be further contained. Examples of the tackifying resin include rosin derivatives, polyterpene resins, petroleum resins, and oil-soluble phenols.

  The thickness of the pressure-sensitive adhesive sheet main body 10 to the pressure-sensitive adhesive layer 11 is preferably 5 μm or more, more preferably 10 μm or more, more preferably 25 μm or more, more preferably 50 μm or more, more preferably 100 μm or more, more preferably 200 μm or more. . The thickness of the pressure-sensitive adhesive sheet main body 10 to the pressure-sensitive adhesive layer 11 is preferably 1000 μm or less, more preferably 900 μm or less, and more preferably 800 μm or less.

  The haze in the thickness direction of the optical pressure-sensitive adhesive sheet main body 10 to the pressure-sensitive adhesive layer 11 is, for example, 3% or less, preferably 2.5% or less, more preferably 2% or less, more preferably 1.5% or less. More preferably, it is 1% or less. The haze is a value measured according to JIS K 7136. Moreover, about the optical adhesive sheet main body 10 thru | or the adhesive layer 11, the total light transmittance in a visible light wavelength range is 85% or more, for example. The total light transmittance is a value measured in accordance with JIS K 7361-1.

The storage elastic modulus at 23 ° C. of the pressure-sensitive adhesive layer 11, that is, the storage elastic modulus at 23 ° C. of the constituent material of the pressure-sensitive adhesive layer 11 is preferably 1.0 × 10 ⁴ Pa or more, more preferably 5.0 × 10 ^4. Pa or higher, more preferably 1.0 × 10 ⁵ Pa or higher. Moreover, the upper limit of the storage elastic modulus in 23 degreeC of the adhesive layer 11 is 1.0 * 10 < ⁷ > Pa, for example. Such a storage elastic modulus can be obtained, for example, from dynamic viscoelasticity measurement performed using a dynamic viscoelasticity measuring device (trade name “ARES”, manufactured by Rheometric Co., Ltd.). In this measurement, the measurement mode is the shear mode, the measurement temperature range is, for example, −70 ° C. to 150 ° C., the temperature increase rate is, for example, 5 ° C./min, and the frequency is, for example, 1 Hz.

  The release liner L1 in the pressure-sensitive adhesive sheet X1 is an element for covering one pressure-sensitive adhesive surface 11 ′ of the pressure-sensitive adhesive sheet body 10, and is peeled off from the pressure-sensitive adhesive sheet body 10 when the pressure-sensitive adhesive sheet body 10 is bonded to an adherend. The release liner L2 in the pressure-sensitive adhesive sheet X1 is an element for covering the other pressure-sensitive adhesive surface 11 ′ of the pressure-sensitive adhesive sheet body 10, and is peeled off from the pressure-sensitive adhesive sheet body 10 when the pressure-sensitive adhesive sheet body 10 is bonded to an adherend. As the release liners L1 and L2, for example, a release liner having a release treatment layer on the surface of a liner substrate such as a resin film or paper, or a release liner made of a low adhesive material such as a fluorine-based polymer or a polyolefin-based resin is used. be able to. Examples of the resin film for the release liner include polyethylene terephthalate. The release treatment layer is, for example, a surface treatment that occurs on the liner substrate by allowing a silicone release treatment agent, a long-chain alkyl release treatment agent, a fluorine release treatment agent, or a molybdenum sulfide release treatment agent to act on the liner substrate surface. Is a layer. Examples of the fluorine-based polymer for the release liner include polytetrafluoroethylene. Examples of the polyolefin resin for the release liner include polyethylene and polypropylene. Each of the release liners L1 and L2 has a thickness of, for example, 5 to 200 μm.

  In the pressure-sensitive adhesive sheet X1, a part or all of the outer peripheral edge 11a of the pressure-sensitive adhesive layer 11 serving as the pressure-sensitive adhesive sheet body 10 is arranged in the sheet in-plane direction, for example, as shown in FIG. 2, the outer peripheral edges L1a, Located at a distance from L2a. The sheet in-plane direction refers to an in-plane direction orthogonal to the thickness direction of the pressure-sensitive adhesive sheet X1 or the pressure-sensitive adhesive sheet body 10 (pressure-sensitive adhesive layer 11). The outer peripheral ends L1a and L2a of the release liners L1 and L2 may be at the same position or different positions in the in-plane direction of the sheet. The outer peripheral ends L1a and L2a shown in FIG. 2 of the release liners L1 and L2 are at the same position in the in-sheet direction. Specifically, in the present embodiment, a part or all of the outer peripheral edge 11a of the adhesive layer 11 is inward of the sheet with respect to the outer peripheral edge L1a closest to the release liner L1 in the in-plane direction of the sheet. 5 to 2000 μm and a distance of 5 to 2000 μm inward of the sheet with respect to the outer peripheral edge L2a closest to the release liner L2. The separation distance D in the sheet surface direction between the outer peripheral edge 11a of the pressure-sensitive adhesive layer 11 located away from the outer peripheral edge L1a of the release liner L1 and the outer peripheral edge L1a is preferably 10 μm or more. Preferably it is 30 micrometers or more, More preferably, it is 40 micrometers or more, More preferably, it is 50 micrometers or more. Further, the separation distance D between the outer peripheral ends 11a and L1a is preferably 1500 μm or less, more preferably 1000 μm or less, more preferably 500 μm or more, and more preferably 300 μm or more. The separation distance D in the sheet surface direction between the outer periphery end 11a of the pressure-sensitive adhesive layer 11 located away from the outer periphery end L2a of the release liner L2 and the outer periphery end L2a is preferably 10 μm or more. Preferably it is 30 micrometers or more, More preferably, it is 40 micrometers or more, More preferably, it is 50 micrometers or more. Further, the separation distance D between the outer peripheral ends 11a and L2a is preferably 1500 μm or less, more preferably 1000 μm or less, more preferably 500 μm or more, and more preferably 300 μm or more.

  The pressure-sensitive adhesive sheet X1 having the above-described configuration can be manufactured, for example, as follows. First, a double-sided pressure-sensitive adhesive sheet with release liner is prepared for producing the pressure-sensitive adhesive sheet X1 through processes such as punching and cutting. For example, a pressure-sensitive adhesive composition for forming a pressure-sensitive adhesive layer 11 is applied on a predetermined release liner to form a pressure-sensitive adhesive composition layer, and a further release liner is laminated on the pressure-sensitive adhesive composition layer, A double-sided PSA sheet with a release liner can be produced by curing the PSA composition in between. This double-sided PSA sheet with release liner includes a pre-first release liner for generating release liner L1, a pre-second release liner for generating release liner L2, and the pre-first and pre-second release liners. It has a laminated structure including a pre-double-sided pressure-sensitive adhesive sheet body (pressure-sensitive adhesive layer) located between them. Next, in a state where the double-sided PSA sheet with release liner is subjected to pressure in the thickness direction, the PSA sheet is processed so that a PSA sheet X1 having a desired outer dimension is formed. Apply. In a state in which the double-sided PSA sheet with release liner is subjected to pressure in the thickness direction, the pre-adhesive sheet body or the adhesive layer as an elastic body of the raw material can be elastically deformed according to the pressure, It stretches elastically in the in-plane direction of the raw material at an elongation corresponding to the pressure, and the outer peripheral edge of the raw material is elastically bulged from between the pre-first release liner and the pre-second release liner. obtain. Examples of the processing means include punching and / or cutting. Examples of punching include so-called Thomson processing, that is, punching using a Thomson blade. As the cutting process, for example, a so-called full back process can be cited. Specifically, in the processing step, a pressure is applied in the thickness direction so that a part or all of the outer peripheral edge of the pressure-sensitive adhesive sheet X1 is newly formed by processing to obtain a pressure-sensitive adhesive sheet X1 having a desired outer dimension. The raw material of the double-sided pressure-sensitive adhesive sheet with a release liner in the received state is subjected to processing such as punching and / or cutting. In the pressure-sensitive adhesive sheet X1 obtained by releasing the pressure state, the pressure-sensitive adhesive layer 11 returns from the elastically deformed state to the non-deformed state, and the release liner is formed at the outer peripheral end of the pressure-sensitive adhesive sheet X1 newly generated in the processing step. A state of retreating inward between L1 and release liner L2 is taken. That is, in the manufactured pressure-sensitive adhesive sheet X1, for example, as shown in FIG. 2, a part or all of the outer peripheral edge 11a of the pressure-sensitive adhesive layer 11 extends from the outer peripheral edges L1a and L2a of the release liners L1 and L2. It will be located inwardly in the inward direction.

  As the pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer 11, for example, a pressure-sensitive adhesive composition that can be cured by a polymerization reaction by irradiation with active energy rays is used. That is, the pressure-sensitive adhesive layer 11 is a cured product of, for example, an active energy ray-curable pressure-sensitive adhesive composition. The active energy ray-curable pressure-sensitive adhesive composition for forming an acrylic pressure-sensitive adhesive layer contains at least a monomer, an oligomer, and a photopolymerization initiator for forming an acrylic polymer. The monomer and oligomer in the composition can be used as a so-called partial polymer of a monomer mixture having a predetermined composition for forming an acrylic polymer. Moreover, the said adhesive composition may contain the other component employ | adopted as needed as a component of the adhesive layer 11 formed. Examples of the active energy ray irradiated to the active energy ray-curable pressure-sensitive adhesive composition for curing the pressure-sensitive adhesive layer 11 include ultraviolet rays, α rays, β rays, γ rays, neutron rays, and electron beams. Preferably, ultraviolet rays are used. In the active energy ray-curable pressure-sensitive adhesive composition for forming an acrylic pressure-sensitive adhesive layer that has been irradiated with an active energy ray, an initiation reaction occurs through the activation of the photopolymerization initiator, leading to the formation of an acrylic polymer. The polymerization reaction proceeds. When active energy ray irradiation such as ultraviolet irradiation is adopted as a curing method for the curable pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer, even when the coating film of the pressure-sensitive adhesive composition is relatively thick, it is cured appropriately. It is easy to obtain a pressure-sensitive adhesive layer. Therefore, the configuration that the pressure-sensitive adhesive layer 11 is a cured product of the active energy ray-curable pressure-sensitive adhesive composition is suitable for realizing the pressure-sensitive adhesive layer 11 that is sufficiently cured even if it is relatively thick.

  Examples of the photopolymerization initiator include benzoin ether photopolymerization initiators, acetophenone photopolymerization initiators, α-ketol photopolymerization initiators, aromatic sulfonyl chloride photopolymerization initiators, and photoactive oxime-based light. Examples include a polymerization initiator, a benzoin photopolymerization initiator, a benzyl photopolymerization initiator, a benzophenone photopolymerization initiator, a ketal photopolymerization initiator, and a thioxanthone photopolymerization initiator. Examples of the benzoin ether photopolymerization initiator include benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isopropyl ether, benzoin isobutyl ether, and 2,2-dimethoxy-1,2-diphenylethane-1-one. Can be mentioned. Examples of the acetophenone-based photopolymerization initiator include 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 1-hydroxycyclohexyl phenyl ketone, 4-phenoxydichloroacetophenone, and 4- (t-butyl). ) Dichloroacetophenone. Examples of the α-ketol photopolymerization initiator include 2-methyl-2-hydroxypropiophenone and 1- [4- (2-hydroxyethyl) phenyl] -2-methylpropan-1-one. . Examples of the aromatic sulfonyl chloride photopolymerization initiator include 2-naphthalenesulfonyl chloride. Examples of the photoactive oxime photopolymerization initiator include 1-phenyl-1,1-propanedione-2- (o-ethoxycarbonyl) -oxime. Examples of the benzoin photopolymerization initiator include benzoin. Examples of the benzyl photopolymerization initiator include benzyl. Examples of the benzophenone photopolymerization initiator include benzophenone, benzoylbenzoic acid, 3,3′-dimethyl-4-methoxybenzophenone, and polyvinylbenzophenone. Examples of the ketal photopolymerization initiator include benzyl dimethyl ketal. Examples of the thioxanthone photopolymerization initiator include thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-diisopropylthioxanthone, and dodecylthioxanthone. The content of the photopolymerization initiator in the active energy ray-curable pressure-sensitive adhesive composition is, for example, 0.01 to 3% by weight.

  As the pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer 11, a solvent-type pressure-sensitive adhesive composition or an emulsion-type pressure-sensitive adhesive composition that already contains an acrylic polymer as a pressure-sensitive adhesive and can be cured by, for example, heat drying may be used. . The said composition may contain the other component employ | adopted as needed as a component of the adhesive layer 11 formed. The acrylic polymer in the pressure-sensitive adhesive composition can be obtained by polymerizing raw material monomer components for forming an acrylic polymer. Examples of the polymerization technique include solution polymerization, emulsion polymerization, and bulk polymerization. When performing solution polymerization, for example, aromatic hydrocarbons, aliphatic hydrocarbons, alicyclic hydrocarbons, esters, and ketones can be used as a solvent. Examples of the aromatic hydrocarbon solvent include toluene and benzene. Examples of the aliphatic hydrocarbon solvent include n-hexane and n-heptane. Examples of the alicyclic hydrocarbon solvents include cyclohexane and methylcyclohexane. Examples of the solvent for esters include ethyl acetate and n-butyl acetate. Examples of the ketone solvent include methyl ethyl ketone and methyl isobutyl ketone. In the solution polymerization, one type of solvent may be used, or two or more types of solvents may be used.

  A polymerization initiator can be used when polymerizing the raw material monomer component to obtain an acrylic polymer. Depending on the type of the polymerization reaction, for example, a photopolymerization initiator or a thermal polymerization initiator can be used. In the polymerization, one type of polymerization initiator may be used, or two or more types of polymerization initiators may be used.

  Examples of the photopolymerization initiator include the benzoin ether photopolymerization initiator, the acetophenone photopolymerization initiator, the α-ketol photopolymerization initiator, the aromatic sulfonyl chloride photopolymerization initiator, and the photoactive oxime light. Examples include a polymerization initiator, a benzoin photopolymerization initiator, a benzyl photopolymerization initiator, a benzophenone photopolymerization initiator, a ketal photopolymerization initiator, and a thioxanthone photopolymerization initiator. The usage-amount of a photoinitiator is 0.01-3 weight part with respect to monomer component whole quantity (100 weight part), for example.

  Examples of the thermal polymerization initiator include an azo polymerization initiator, a peroxide polymerization initiator, and a redox polymerization initiator. Examples of the azo polymerization initiator include 2,2′-azobisisobutyronitrile, 2,2′-azobis-2-methylbutyronitrile, and 2,2′-azobis (2-methylpropionic acid) dimethyl. And 4,4′-azobis-4-cyanovaleric acid. Examples of the peroxide-based polymerization initiator include benzoyl peroxide and tert-butyl permaleate. The usage-amount of a thermal-polymerization initiator is 0.05-0.3 weight part with respect to monomer component whole quantity (100 weight part), for example.

  In the polymerization for obtaining the acrylic polymer, a chain transfer agent can be used to adjust the molecular weight of the acrylic polymer. Examples of the chain transfer agent include α-thioglycerol, 2-mercaptoethanol, 2,3-dimercapto-1-propanol, octyl mercaptan, t-nonyl mercaptan, dodecyl mercaptan (lauryl mercaptan), t-dodecyl mercaptan, glycidyl mercaptan. Thioglycolic acid, methyl thioglycolate, ethyl thioglycolate, propyl thioglycolate, butyl thioglycolate, t-butyl thioglycolate, 2-ethylhexyl thioglycolate, octyl thioglycolate, isooctyl thioglycolate, thio And decyl glycolate and dodecyl thioglycolate. As the chain transfer agent, one type of chain transfer agent may be used, or two or more types of chain transfer agents may be used. In this embodiment, α-thioglycerol is preferably used as the chain transfer agent. The amount of the chain transfer agent used is, for example, 0.01 to 0.5 parts by weight with respect to the total amount of monomer components (100 parts by weight) for obtaining an acrylic polymer.

  When the pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer 11 such as an active energy ray-curable pressure-sensitive adhesive composition, a solvent-type pressure-sensitive adhesive composition, or an emulsion-type pressure-sensitive adhesive composition contains the above-mentioned acrylic oligomer, The oligomer can be obtained by polymerizing raw material monomer components having a predetermined composition. Examples of the polymerization technique include solution polymerization, emulsion polymerization, and bulk polymerization. Examples of the solvent for the solution polymerization include those described above as the solvent that can be used for the solution polymerization for obtaining the acrylic polymer. In the solution polymerization, one type of solvent may be used, or two or more types of solvents may be used. Moreover, when polymerizing a raw material monomer component in order to obtain the said oligomer, a polymerization initiator can be used. Examples of the polymerization initiator include the above-described photopolymerization initiator and thermal polymerization initiator as a polymerization initiator that can be used for polymerization for obtaining an acrylic polymer. In the polymerization, one type of polymerization initiator may be used, or two or more types of polymerization initiators may be used.

  For example, as shown in FIG. 2, for example, as shown in FIG. 2, a part or the entire region of the outer peripheral edge 11 a of the pressure-sensitive adhesive sheet main body 10 or the pressure-sensitive adhesive layer 11 in the pressure-sensitive adhesive sheet X1 which is a double-sided pressure-sensitive adhesive sheet with a release liner manufactured as described above. The release liners L1 and L2 are positioned away from the outer peripheral ends L1a and L2a in the sheet plane direction. The outer peripheral end 11a of the pressure-sensitive adhesive layer 11 extends from the outer peripheral ends L1a and L2a of the release liners L1 and L2 so as to form, for example, a concave shape in the outer peripheral end of the sheet in the cross section in the thickness direction of the adhesive sheet X1. It has a region located away in the inward direction. Then, a separation distance D in the sheet surface direction between the outer peripheral edge 11a of the pressure-sensitive adhesive layer 11 located away from the outer peripheral edges L1a and L2a of the release liners L1 and L2 and the outer peripheral edges L1a and L2a. Is 5 to 2000 μm as described above. When the release liner L1 or the release liner L2 is peeled from the pressure-sensitive adhesive sheet X1, the outer peripheral edge 11a of the pressure-sensitive adhesive sheet body 10 or the pressure-sensitive adhesive layer 11 extends from the outer peripheral edges L1a and L2a of the release liners L1 and L2. If a part (outer peripheral edge separation part) located away in the inward direction is used, it is easy to perform the peeling work. Specifically, at the outer peripheral edge separation site, for example, the operator's fingertip can be easily brought into contact with the release liner L1 or release liner L2 to be peeled without being brought into contact with the adhesive layer 11, and therefore, the peeling target is peeled off. It is easy to start appropriate deformation for peeling in the release liner so that separation of the two starts from the edge of the interface between the liner and the pressure-sensitive adhesive layer 11. As described above, in the pressure-sensitive adhesive sheet X1, the release liners L1 and L2 can be easily peeled from the pressure-sensitive adhesive sheet body 10 by, for example, manual work.

  Further, at the outer peripheral end separation portion of the pressure-sensitive adhesive sheet X1, as described above, the release liner L1 to be peeled off without bringing the fingertip of the operator into contact with the pressure-sensitive adhesive layer 11 when the release liner L1 or the release liner L2 is peeled off. Easy to contact the release liner L2. At the same time, at the outer peripheral end separation portion of the pressure-sensitive adhesive sheet X1, as described above, the separation is started from the edge of the interface between the release liner L1 or the release liner L2 and the pressure-sensitive adhesive layer 11 to be peeled. It is easy to initiate appropriate deformation for release in the release liner. These are the pressure-sensitive adhesive sheet X1 capable of peeling the release liner by using the outer peripheral edge separation part, respectively, and the pressure-sensitive adhesive sheet body 10 or a part of the pressure-sensitive adhesive surface 11 ′ of the pressure-sensitive adhesive layer 11 when the release liner is peeled off. It is suitable for suppressing the occurrence of partial breakage or breakage in the pressure-sensitive adhesive surface 11 ′ or the pressure-sensitive adhesive layer 11 by being pulled by the release liner.

  In addition, in the adhesive sheet X1, the sheet surface between the outer peripheral end 11a of the adhesive layer 11 located away from the outer peripheral ends L1a and L2a of the release liners L1 and L2 and the outer peripheral ends L1a and L2a. The inward separation distance D is 5 to 2000 μm as described above. As described above, the pressure-sensitive adhesive sheet X1 having such a configuration is suitable for efficient production using elastic deformation of the pressure-sensitive adhesive layer and subsequent shape recovery. Separation distance (separation distance D) between the outer peripheral ends L1a, L2a of the release liners L1, L2 and the outer peripheral end 11a of the pressure-sensitive adhesive layer 11 as a result of using the elastic deformation of the pressure-sensitive adhesive layer and the subsequent shape recovery Tends to be within a relatively short range of 5 to 2000 μm. On the other hand, in order to manufacture a double-sided PSA sheet with a release liner having a larger outline size than the PSA sheet body 10 or the PSA layer 11, for example, 5000 μm or more, the outer dimensions are the same as, for example, the PSA sheet body 10 or the PSA layer 11. After manufacturing a double-sided pressure-sensitive adhesive sheet with a release liner associated with the pressure-sensitive adhesive surfaces 11 ′ and 11 ′, it is necessary to replace each release liner with a release liner having a larger outer dimension than the pressure-sensitive adhesive sheet body 10. However, such a method is not efficient from the viewpoint of material cost and the number of processes. Adhesive having a separation distance D between the outer peripheral end 11a of the adhesive layer 11 located away from the outer peripheral ends L1a and L2a of the release liners L1 and L2 in the sheet surface direction and the outer peripheral ends L1a and L2a. The sheet X1 is suitable for efficient production through the above-described process using elastic deformation of the pressure-sensitive adhesive layer and subsequent shape recovery.

  As described above, the pressure-sensitive adhesive sheet X1, which is a double-sided pressure-sensitive adhesive sheet with a release liner, facilitates the peeling operation of the release liners L1 and L2, and suppresses partial breakage or loss of the pressure-sensitive adhesive layer 11 when the release liner is peeled off. Suitable for efficient production. In addition, the separation distance D between the outer peripheral end 11a of the adhesive layer 11 located away from the outer peripheral ends L1a and L2a of the release liners L1 and L2 and the outer peripheral ends L1a and L2a in the in-plane direction of the sheet is 5 to 2000 μm. The pressure-sensitive adhesive sheet X1 achieves the dimensions required for the pressure-sensitive adhesive sheet body 10, but the outer dimensions of the pressure-sensitive adhesive sheet X1, that is, the outer dimensions of the release liners L1 and L2, greatly exceed the dimensions of the pressure-sensitive adhesive sheet body 10. Suitable for avoiding.

  As described above, the thickness of the pressure-sensitive adhesive sheet main body 10 to the pressure-sensitive adhesive layer 11 in the pressure-sensitive adhesive sheet X1 is preferably 5 μm or more, more preferably 10 μm or more, more preferably 25 μm or more, more preferably 50 μm or more, more preferably 100 μm. As mentioned above, More preferably, it is 200 micrometers or more. Such a configuration is suitable for realizing sufficient adhesive force on the adherend in the adhesive layer 11. The pressure-sensitive adhesive layer 11 has a thickness of 25 μm or more, preferably 50 μm or more, more preferably 100 μm or more, and more preferably 200 μm or more. The separation distance D between the outer peripheral ends L1a and L2a of the adhesive layer 11 and the outer peripheral end 11a of the pressure-sensitive adhesive layer 11 is 5 μm or more, which is preferable for ensuring a longer distance. This is because the thicker the pressure-sensitive adhesive layer, the larger the amount of elastic deformation in the in-plane direction of the pressure-sensitive adhesive layer when the pressure-sensitive adhesive layer receives pressure in the thickness direction. On the other hand, from the viewpoint of easy formation of the pressure-sensitive adhesive layer 11, the thickness of the pressure-sensitive adhesive sheet body 10 to the pressure-sensitive adhesive layer 11 is preferably 1000 μm or less, more preferably 900 μm or less, more preferably as described above. 800 μm or less.

The storage elastic modulus at 23 ° C. of the pressure-sensitive adhesive layer 11 is preferably 1.0 × 10 ⁴ Pa or more, more preferably 5.0 × 10 ⁴ Pa or more, and more preferably 1.0 × 10 ^{5 as described above.} Pa or higher. Such a configuration is suitable for efficiently producing the pressure-sensitive adhesive sheet X1 having a separation distance D of 5 to 2000 μm at the above-described outer peripheral edge separation site by utilizing elastic deformation of the pressure-sensitive adhesive layer and subsequent shape recovery. It is.

  FIG. 3 is a partial cross-sectional view of an adhesive sheet X2 that is a double-sided adhesive sheet with a release liner according to an embodiment of the present invention. The pressure-sensitive adhesive sheet X2 has a laminated structure including a pressure-sensitive adhesive sheet body 20 as a double-sided pressure-sensitive adhesive sheet body and release liners L1 and L2. The pressure-sensitive adhesive sheet body 20 is positioned between the release liners L1 and L2, and is positioned between the pressure-sensitive adhesive layer 21 that is the first pressure-sensitive adhesive layer, the pressure-sensitive adhesive layer 22 that is the second pressure-sensitive adhesive layer, and the pressure-sensitive adhesive layers 21 and 22. In this embodiment, it has a light transmitting property. The pressure-sensitive adhesive layer 21 in the pressure-sensitive adhesive sheet body 20 has a pressure-sensitive adhesive surface 21 ′ that can be attached to an adherend, and the pressure-sensitive adhesive layer 22 has a pressure-sensitive adhesive surface 22 ′ that can be attached to an adherend. Such a pressure-sensitive adhesive sheet main body 20 is a double-sided pressure-sensitive adhesive sheet for optics that can be used in the manufacture of flat panel displays or the like, for example. A display device such as a liquid crystal display or an input device such as a touch panel has a laminated structure including various substrates and film bodies. As an optical double-sided pressure-sensitive adhesive sheet for joining predetermined parts adjacent to each other in the laminated structure. Alternatively, the pressure-sensitive adhesive sheet main body 20 can be used as an optical double-sided pressure-sensitive adhesive sheet for filling a gap between adjacent parts. The pressure-sensitive adhesive sheet X2 is a double-sided pressure-sensitive adhesive sheet with a release liner with release liners L1 and L2 for covering the pressure-sensitive adhesive surfaces 21 ′ and 22 ′ of the pressure-sensitive adhesive sheet body 20.

  The pressure-sensitive adhesive layers 21 and 22 in the pressure-sensitive adhesive sheet main body 20 each contain a pressure-sensitive adhesive as a main agent. The adhesive and other constituent materials in the adhesive layers 21 and 22 are the same as described above for the adhesive and other constituent materials in the adhesive layer 11. The pressure-sensitive adhesive layer 21 and the pressure-sensitive adhesive layer 22 may be formed from pressure-sensitive adhesive compositions having the same composition, or may be formed from pressure-sensitive adhesive compositions having different compositions.

  The thickness of each of the pressure-sensitive adhesive layers 21 and 22 is preferably 5 μm or more, more preferably 10 μm or more, more preferably 25 μm or more, more preferably 50 μm or more, more preferably 100 μm or more, and more preferably 200 μm or more. The thicknesses of the pressure-sensitive adhesive layers 21 and 22 are each preferably 1000 μm or less, more preferably 900 μm or less, and more preferably 800 μm or less.

  The haze in the thickness direction of the optical pressure-sensitive adhesive sheet body 20 is, for example, 3% or less, preferably 2.5% or less, more preferably 2% or less, more preferably 1.5% or less, more preferably 1 % Or less. The haze is a value measured according to JIS K 7136. Moreover, about the adhesive sheet main body 20 for optics, the total light transmittance in a visible light wavelength range is 85% or more, for example. The total light transmittance is a value measured in accordance with JIS K 7361-1.

The storage elastic modulus at 23 ° C. of the pressure-sensitive adhesive layers 21 and 22 is preferably 1.0 × 10 ⁴ Pa or more, more preferably 5.0 × 10 ⁴ Pa or more, more preferably 1.0 × 10 ⁵ Pa. That's it. Moreover, the upper limit of the storage elastic modulus in 23 degreeC of the adhesive layers 21 and 22 is 1.0 * 10 < ⁷ > Pa, for example. Such a storage elastic modulus can be obtained from dynamic viscoelasticity measurement using, for example, a dynamic viscoelasticity measuring device (trade name “ARES”, manufactured by Rheometric Co., Ltd.) as described above.

  The base material 23 of the pressure-sensitive adhesive sheet body 20 is a part that functions as a support in the pressure-sensitive adhesive sheet body 20. Examples of the material for forming the base material 23 include polyesters such as polyethylene terephthalate (PET), polyolefins such as polypropylene and polyethylene, polycarbonates, polyamides, polyimides, acrylics, polystyrenes, acetates, polyethersulfones, and triacetylcellulose. Can be mentioned. The base material 23 may be made of one type of material, or may be made of two or more types of materials. The base material 23 may have a multilayer structure. Further, the surface on the pressure-sensitive adhesive layer 21 side and the surface on the pressure-sensitive adhesive layer 22 side of the base material 23 may each be subjected to a surface treatment for improving adhesion with the pressure-sensitive adhesive layer. Examples of such surface treatment include physical treatment such as corona treatment and plasma treatment, and chemical treatment such as undercoating treatment. The thickness of such a base material 23 is 15-150 micrometers, Preferably it is 25-125 micrometers, More preferably, it is 38-100 micrometers.

  The release liner L1 of the pressure-sensitive adhesive sheet X2 is an element for covering the pressure-sensitive adhesive surface 21 ′ of the pressure-sensitive adhesive sheet body 20, and is peeled off from the pressure-sensitive adhesive sheet body 20 when the pressure-sensitive adhesive sheet body 20 is bonded to an adherend. The release liner L2 of the pressure-sensitive adhesive sheet X2 is an element for covering the pressure-sensitive adhesive surface 22 ′ of the pressure-sensitive adhesive sheet body 20, and is peeled off from the pressure-sensitive adhesive sheet body 20 when the pressure-sensitive adhesive sheet body 20 is bonded to an adherend. The configuration and thickness of the release liners L1 and L2 of the adhesive sheet X2 are as described above for the configuration and thickness of the release liners L1 and L2 of the adhesive sheet X1.

  In the pressure-sensitive adhesive sheet X2, a part or all of the outer peripheral edge 21a of the pressure-sensitive adhesive layer 21 of the pressure-sensitive adhesive sheet main body 20 is formed in the sheet in-plane direction, for example, as shown in FIG. 4, the outer peripheral edges L1a of the release liners L1 and L2. , At a position away from L2a. The sheet in-plane direction refers to an in-plane direction orthogonal to the thickness direction of the pressure-sensitive adhesive sheet X2 or the pressure-sensitive adhesive sheet body 20. The outer peripheral ends L1a and L2a of the release liners L1 and L2 may be at the same position or different positions in the in-plane direction of the sheet. With respect to the release liners L1 and L2, the outer peripheral ends L1a and L2a shown in FIG. Specifically, in the present embodiment, a part or all of the outer peripheral end 21a of the adhesive layer 21 is inward of the sheet with respect to the outer peripheral end L1a closest to the release liner L1 in the sheet in-plane direction. 5 to 2000 μm and a distance of 5 to 2000 μm inward of the sheet with respect to the outer peripheral edge L2a closest to the release liner L2. The separation distance D1 in the sheet surface direction between the outer periphery end 21a of the pressure-sensitive adhesive layer 21 located away from the outer periphery end L1a of the release liner L1 and the outer periphery end L1a is preferably 10 μm or more. Preferably it is 30 micrometers or more, More preferably, it is 40 micrometers or more, More preferably, it is 50 micrometers or more. The separation distance D1 between the outer peripheral ends 21a and L1a is preferably 1500 μm or less, more preferably 1000 μm or less, more preferably 500 μm or more, and more preferably 300 μm or more. The separation distance D1 in the sheet surface direction between the outer peripheral edge 21a of the pressure-sensitive adhesive layer 21 located away from the outer peripheral edge L2a of the release liner L2 and the outer peripheral edge L2a is preferably 10 μm or more. Preferably it is 30 micrometers or more, More preferably, it is 40 micrometers or more, More preferably, it is 50 micrometers or more. The separation distance D1 between the outer peripheral ends 21a and L2a is preferably 1500 μm or less, more preferably 1000 μm or less, more preferably 500 μm or more, and more preferably 300 μm or more. On the other hand, the separation distance D2 in the sheet surface direction between the outer periphery end 22a of the pressure-sensitive adhesive layer 22 positioned away from the outer periphery end L2a of the release liner L2 and the outer periphery end L2a is preferably 10 μm or more. More preferably, it is 30 μm or more, more preferably 40 μm or more, and more preferably 50 μm or more. The separation distance D2 between the outer peripheral ends 22a and L2a is preferably 1500 μm or less, more preferably 1000 μm or less, more preferably 500 μm or more, and more preferably 300 μm or more. The separation distance D2 in the sheet surface direction between the outer peripheral edge 22a of the pressure-sensitive adhesive layer 22 located away from the outer peripheral edge L1a of the release liner L1 and the outer peripheral edge L1a is preferably 10 μm or more. Preferably it is 30 micrometers or more, More preferably, it is 40 micrometers or more, More preferably, it is 50 micrometers or more. The separation distance D2 between the outer peripheral ends 22a and L1a is preferably 1500 μm or less, more preferably 1000 μm or less, more preferably 500 μm or more, and more preferably 300 μm or more.

  The pressure-sensitive adhesive sheet X2 having the above-described configuration can be manufactured, for example, as follows. First, a double-sided PSA sheet with release liner is prepared for producing the PSA sheet X2 through a process such as punching or cutting. This double-sided PSA sheet with release liner includes a pre-first release liner for generating release liner L1, a pre-second release liner for generating release liner L2, and the pre-first and pre-second release liners. It has a laminated structure including a pre-double-sided pressure-sensitive adhesive sheet main body positioned therebetween. This pre-double-sided pressure-sensitive adhesive sheet main body is, for example, on the pre-first release liner side and produces a pressure-sensitive adhesive layer 21 and, for example, on the pre-second release liner side, produces a pressure-sensitive adhesive layer 22. The second pressure-sensitive adhesive layer and a base material located between the first and second pressure-sensitive adhesive layers have a laminated structure. The pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer 21, the method for forming the pressure-sensitive adhesive layer 21 from the composition, the pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer 22, and the formation of the pressure-sensitive adhesive layer 22 from the composition About the method, it is the same as that mentioned above as the formation method of the adhesive composition for adhesive layer 11 formation and the adhesive layer 11 from the said composition. Next, in a state in which the double-sided PSA sheet with release liner is subjected to pressure in the thickness direction, the PSA sheet is processed so that a PSA sheet X2 having a desired outer dimension is formed. Apply. In a state where the double-sided PSA sheet raw material is subjected to pressure in the thickness direction, each adhesive layer as an elastic body in the pre-double-sided PSA sheet body of the raw material can be elastically deformed according to the pressure, It stretches elastically in the in-plane direction of the raw material at an elongation ratio according to the elasticity, and is elastic from between the pre-first release liner or pre-second release liner and the base material of the pre-double-sided PSA sheet at the outer peripheral edge of the raw material. Can be in a bulging state. Examples of the processing means include punching and / or cutting. Examples of punching include so-called Thomson processing, that is, punching using a Thomson blade. As the cutting process, for example, a so-called full back process can be cited. Specifically, in the processing step, a pressure is applied in the thickness direction so that a part or the whole of the outer peripheral edge of the pressure-sensitive adhesive sheet X2 is newly formed by processing to obtain a pressure-sensitive adhesive sheet X2 having a desired outer dimension. The raw material of the double-sided pressure-sensitive adhesive sheet with a release liner in the received state is subjected to processing such as punching and / or cutting. In the pressure-sensitive adhesive sheet X2 obtained by releasing the pressurized state, the pressure-sensitive adhesive layers 21 and 22 return from the elastically deformed state to the non-deformed state, and at the outer peripheral edge of the pressure-sensitive adhesive sheet X2 newly generated in the processing step. A state where the release liner L1 or the release liner L2 and the base material 23 are retracted inward is taken. That is, in the manufactured adhesive sheet X2, for example, as shown in FIG. 4, a part or all of the outer peripheral end 21a of the adhesive layer 21 is within the sheet surface from the outer peripheral ends L1a and L2a of the release liners L1 and L2. The outer peripheral end 22a of the pressure-sensitive adhesive layer 22 is positioned inwardly in the sheet plane direction from the outer peripheral ends L1a and L2a of the release liners L1 and L2. .

  For example, as shown in FIG. 4, part or all of the outer peripheral ends 21 a and 22 a of the pressure-sensitive adhesive layers 21 and 22 of the pressure-sensitive adhesive sheet main body 20 in the pressure-sensitive adhesive sheet X <b> 2 that is a double-sided pressure-sensitive adhesive sheet with a release liner, It is located away from the outer peripheral ends L1a and L2a of L2 in the sheet plane direction. And the separation distance D1 in the sheet surface direction between the outer circumferential edge 21a of the adhesive layer 21 located away from the outer circumferential edges L1a and L2a of the release liners L1 and L2 and the outer circumferential edges L1a and L2a. Is 5 to 2000 μm as described above. Further, a separation distance D2 in the sheet surface direction between the outer peripheral edge 22a of the adhesive layer 22 located away from the outer peripheral edges L1a and L2a of the release liners L1 and L2 and the outer peripheral edges L1a and L2a. Is 5 to 2000 μm as described above. When the release liner L1 is peeled from the pressure-sensitive adhesive sheet X2, the outer peripheral edge 21a of the pressure-sensitive adhesive layer 21 of the pressure-sensitive adhesive sheet body 20 is located at least away from the outer peripheral edge L1a of the release liner L1 in the sheet surface direction. When a part (first outer peripheral edge separation part) or a part (second outer peripheral edge separation part) in which the outer peripheral edge 22a of the adhesive layer 22 is located at least away from the outer peripheral edge L2a of the release liner L2 in the sheet surface direction is used. Easy to perform peeling work. Specifically, in the first outer peripheral edge separation portion, for example, the operator's fingertip is easily brought into contact with the release liner L1 to be peeled without being brought into contact with the adhesive layer 21, and accordingly, the release liner L1 and the adhesive It is easy to start appropriate deformation for peeling in the release liner L1 so that separation of both starts from the edge of the interface with the layer 21. In addition, at the second outer peripheral edge separation site, for example, the operator's fingertip is easily brought into contact with the release liner L2 to be peeled without being brought into contact with the adhesive layer 22, and accordingly, the release liner L2 and the adhesive layer 22 It is easy to start appropriate deformation for peeling in the release liner L2 so that separation of both starts from the end of the interface between the two. Thus, in the pressure sensitive adhesive sheet X2, the release liners L1 and L2 can be easily peeled from the pressure sensitive adhesive sheet main body 20, for example, manually.

  Further, at the first outer peripheral edge separation portion of the pressure-sensitive adhesive sheet X2, as described above, when the release liner L1 is peeled off, the operator's fingertip or the like does not come into contact with the pressure-sensitive adhesive layer 21, but comes into contact with the release liner L1 to be peeled Easy to make. At the same time, at the first outer peripheral end separation portion of the pressure-sensitive adhesive sheet X2, as described above, the release liner L1 so that separation of both starts from the edge of the interface between the release liner L1 to be peeled and the pressure-sensitive adhesive layer 21. It is easy to start appropriate deformation for peeling. At the second outer peripheral edge separation portion of the pressure-sensitive adhesive sheet X2, as described above, the operator's fingertip or the like is not brought into contact with the pressure-sensitive adhesive layer 22 when peeling off the release liner L2, and is easily brought into contact with the release liner L2 to be peeled off. . At the same time, at the second outer peripheral end separation portion of the pressure-sensitive adhesive sheet X2, as described above, the release liner L2 so that separation of both starts from the end of the interface between the release liner L2 to be peeled and the pressure-sensitive adhesive layer 22. It is easy to start appropriate deformation for peeling. In the pressure-sensitive adhesive sheet X2 that can release the release liner using each outer peripheral edge separation portion, a part of the pressure-sensitive adhesive surface of the pressure-sensitive adhesive sheet body 20 is pulled by the release liner when the release liner is peeled off. Therefore, it is suitable for suppressing the occurrence of partial breakage or loss on the pressure-sensitive adhesive surface or the pressure-sensitive adhesive layer.

  In addition, in the adhesive sheet X2, the sheet surface between the outer peripheral end 21a of the adhesive layer 21 located away from the outer peripheral ends L1a and L2a of the release liners L1 and L2 in the sheet surface direction and the outer peripheral ends L1a and L2a. The inward separation distance D1 is 5 to 2000 μm as described above. In the pressure-sensitive adhesive sheet X2, in the sheet surface direction between the outer peripheral edge 22a of the pressure-sensitive adhesive layer 22 positioned away from the outer peripheral edges L1a and L2a of the release liners L1 and L2 and the outer peripheral edges L1a and L2a. The separation distance D2 is 5 to 2000 μm as described above. The pressure-sensitive adhesive sheet X2 having such a configuration is suitable for efficient production using elastic deformation of the pressure-sensitive adhesive layer and subsequent shape recovery. The distance between the outer peripheral ends L1a and L2a of the release liners L1 and L2 and the outer peripheral ends 21a and 22a of the adhesive layers 21 and 22 as a result of using the elastic deformation of the adhesive layer and the subsequent shape recovery ( The separation distances D1 and D2) tend to be within a relatively short range of 5 to 2000 μm. On the other hand, in order to manufacture a double-sided PSA sheet with a release liner having a larger outer dimension than, for example, 5000 μm or more than the PSA body 20 or PSA layers 21 and 22, for example, the PSA sheet body 20 or PSA layers 21 and 22 After manufacturing a double-sided pressure-sensitive adhesive sheet with a release liner associated with the pressure-sensitive adhesive surfaces 21 ′ and 22 ′, release liners having the same outer dimensions are pasted on the release liner having a larger outer dimension than the pressure-sensitive adhesive sheet body 20. There is a need. However, such a method is not efficient from the viewpoint of material cost and the number of processes. Separation distances D1 and D2 between the outer peripheral ends L1a and L2a of the adhesive layers 21 and 22 positioned away from the outer peripheral ends L1a and L2a of the release liners L1 and L2 and the outer peripheral ends L1a and L2a. The pressure-sensitive adhesive sheet X2 having a thickness of 5 to 2000 μm is suitable for efficient production through the above-described process using elastic deformation of the pressure-sensitive adhesive layer and subsequent shape recovery.

  As described above, the pressure-sensitive adhesive sheet X2 that is a double-sided pressure-sensitive adhesive sheet with a release liner facilitates the release operation of the release liners L1 and L2, and causes partial damage or loss of the pressure-sensitive adhesive layer 21 or the pressure-sensitive adhesive layer 222 when the release liner is peeled off. It is suitable for suppressing production and for efficient production. In addition, the separation distance D1 between the outer peripheral ends 21a and 22a of the adhesive layers 21 and 22 and the outer peripheral ends L1a and L2a which are located away from the outer peripheral ends L1a and L2a of the release liners L1 and L2 in the sheet in-plane direction. , D2 is 5 to 2000 μm, while the dimensions required for the pressure sensitive adhesive sheet main body 20 are realized, the outer dimensions of the pressure sensitive adhesive sheet X2, that is, the outer dimensions of the release liners L1 and L2, increase the dimensions of the pressure sensitive adhesive sheet main body 20. Suitable for avoiding over-exceeding.

  As described above, the thickness of each of the pressure-sensitive adhesive layers 21 and 22 in the pressure-sensitive adhesive sheet X2 is preferably 5 μm or more, more preferably 10 μm or more, more preferably 25 μm or more, more preferably 50 μm or more, more preferably 100 μm or more. More preferably, it is 200 μm or more. Such a configuration is suitable for realizing sufficient adhesive force on the adherend in the adhesive layers 21 and 22. The structure in which the thickness of the pressure-sensitive adhesive layer 21 is 25 μm or more, preferably 50 μm or more, more preferably 100 μm or more, and more preferably 200 μm or more is the release liner L1, L2 in the first outer peripheral edge separation portion. The separation distance D1 between the outer peripheral ends L1a and L2a of the adhesive layer 21 and the outer peripheral end 21a of the pressure-sensitive adhesive layer 21 is 5 μm or more, which is preferable for ensuring a longer distance. The structure in which the thickness of the pressure-sensitive adhesive layer 22 is 25 μm or more, preferably 50 μm or more, more preferably 100 μm or more, and more preferably 200 μm or more is the release liner L1, L2 in the second outer peripheral edge separation portion. The separation distance D2 between the outer peripheral ends L1a, L2a of the adhesive and the outer peripheral end 22a of the pressure-sensitive adhesive layer 22 is 5 μm or more, which is suitable for ensuring a longer distance. The thicker the pressure-sensitive adhesive layer, the larger the amount of elastic deformation in the in-plane direction of the pressure-sensitive adhesive layer when the pressure-sensitive adhesive layer receives pressure in the thickness direction. On the other hand, from the viewpoint of easy formation of the pressure-sensitive adhesive layers 21, 22, the thickness of the pressure-sensitive adhesive layers 21, 22 is preferably 1000 μm or less, more preferably 900 μm or less, and more preferably as described above. Is 800 μm or less.

As described above, the storage elastic modulus of the pressure-sensitive adhesive layer 21 at 23 ° C. is preferably 1.0 × 10 ⁴ Pa or more, more preferably 5.0 × 10 ⁴ Pa or more, and more preferably 1.0 × 10 ^5. Pa or higher. In such a configuration, the pressure-sensitive adhesive sheet X2 having a separation distance D1 of 5 to 2000 μm at the first outer peripheral edge separation portion described above is efficiently manufactured using elastic deformation of the pressure-sensitive adhesive layer and subsequent shape recovery. It is suitable. As described above, the storage elastic modulus of the pressure-sensitive adhesive layer 22 at 23 ° C. is preferably 1.0 × 10 ⁴ Pa or more, more preferably 5.0 × 10 ⁴ Pa or more, more preferably 1.0 × 10 ^5. Pa or higher. In such a configuration, the pressure-sensitive adhesive sheet X2 having a separation distance D1 of 5 to 2000 μm at the second outer peripheral end separation portion described above is efficiently manufactured using elastic deformation of the pressure-sensitive adhesive layer and subsequent shape recovery. It is suitable.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.

[Production example of acrylic oligomer]
In a reaction vessel, 60 parts by weight of dicyclopentanyl methacrylate (DCPMA), 40 parts by weight of methyl methacrylate (MMA), 3.5 parts by weight of α-thioglycerol as a chain transfer agent, and a polymerization solvent A mixture containing 100 parts by weight of toluene was stirred at 70 ° C. for 1 hour under a nitrogen atmosphere. Next, 0.2 part by weight of 2,2′-azobisisobutyronitrile as a polymerization initiator was added to the mixture in the reaction vessel to prepare a reaction solution, and the reaction was performed at 70 ° C. for 2 hours. Subsequently, the reaction was performed at 80 ° C. for 2 hours. Thereafter, the reaction solution in the reaction vessel was placed in a temperature atmosphere of 130 ° C., and toluene, chain transfer agent, and unreacted monomer were removed by drying from the reaction solution. Thereby, a solid acrylic oligomer was obtained. The acrylic oligomer had a weight average molecular weight (Mw) of 5.1 × 10 ³ .

[Preparation Example of Acrylic Adhesive Composition C1]
A monomer mixture containing 78 parts by weight of 2-ethylhexyl acrylate (2EHA), 18 parts by weight of N-vinyl-2-pyrrolidone (NVP) and 4 parts by weight of 2-hydroxyethyl acrylate (HEA) 0.035 parts by weight of a photopolymerization initiator (trade name “Irgacure 651”, manufactured by BASF) and 0.035 parts by weight of a second photopolymerization initiator (trade name “Irgacure 184”, manufactured by BASF) were added. Thereafter, the mixture was irradiated with ultraviolet rays using an ultraviolet irradiation device until the viscosity of the mixture reached about 20 Pa · s while measuring the viscosity using a viscosity measuring device. In the viscosity measurement, the rotor rotation speed of the apparatus was 10 rpm, and the measurement temperature was 30 ° C. As a result, a prepolymer composition (containing a monomer component that did not undergo a polymerization reaction) was obtained as a partial polymer obtained by polymerizing a part of the monomer component in the mixture. Then, 100 parts by weight of this prepolymer composition, 11.8 parts by weight of the above acrylic oligomer, 17.6 parts by weight of 2-hydroxyethyl acrylate (HEA), and 1,6-hexanediol diacrylate (HDDA) ) 0.294 parts by weight and 0.353 parts by weight of a silane coupling agent (trade name “KBM-403”, manufactured by Shin-Etsu Chemical Co., Ltd.) were mixed. This obtained the acrylic adhesive composition (acrylic adhesive composition C1).

[Preparation Example of Acrylic Adhesive Composition C2]
The first photopolymerization was initiated with a monomer mixture containing 67 parts by weight of n-butyl acrylate (BA), 14 parts by weight of cyclohexyl acrylate (CHA), and 19 parts by weight of 4-hydroxybutyl acrylate (HBA). 0.09 parts by weight of an agent (trade name “Irgacure 651”, manufactured by BASF) and 0.09 parts by weight of a second photopolymerization initiator (trade name “Irgacure 184”, manufactured by BASF) were added, and then the mixture was mixed. On the other hand, ultraviolet rays were irradiated using an ultraviolet irradiation device until the viscosity of the mixture reached about 20 Pa · s while measuring the viscosity using a viscosity measuring device. In the viscosity measurement, the rotor rotation speed of the apparatus was 10 rpm, and the measurement temperature was 30 ° C. As a result, a prepolymer composition (containing a monomer component that did not undergo a polymerization reaction) was obtained as a partial polymer obtained by polymerizing a part of the monomer component in the mixture. And, 100 parts by weight of this prepolymer composition, 9 parts by weight of 2-hydroxyethyl acrylate (HEA), 8 parts by weight of 4-hydroxybutyl acrylate (HEA), and 0.05 of dipentaerythritol hexaacrylate (DPHA). 12 parts by weight and 0.3 part by weight of a silane coupling agent (trade name “KBM-403”, manufactured by Shin-Etsu Chemical Co., Ltd.) were mixed. This obtained the acrylic adhesive composition (acrylic adhesive composition C2).

[Example 1]
The acrylic pressure-sensitive adhesive composition C1 was applied on a polyethylene terephthalate (PET) -based first release liner (thickness 125 μm, light release type, manufactured by Nitto Denko Corporation) to form a pressure-sensitive adhesive composition layer. . Next, a PET-based second release liner (thickness 125 μm, heavy release type, manufactured by Nitto Denko Corporation) is laminated on the pressure-sensitive adhesive composition layer, and the pressure-sensitive adhesive composition layer is covered to block oxygen. did. In this way, a laminate (laminate L1 ′) having a laminate configuration of [first release liner / adhesive composition layer / second release liner] was obtained. Next, the laminated body L1 ′ was irradiated with ultraviolet rays having an illuminance of 3 mW / cm ² for 300 seconds from the first release liner side using a black light (manufactured by Toshiba Corporation). As a result, the pressure-sensitive adhesive composition layer of the laminate L1 ′ is cured to form a pressure-sensitive adhesive layer, and a laminate (laminate L1) having a laminate configuration of [first release liner / pressure-sensitive adhesive layer / second release liner] is obtained. It was. The thickness of the pressure-sensitive adhesive layer in this laminate L1 is 500 μm. Next, Thomson processing was performed on the laminate L1. Specifically, using a punching machine and a Thomson blade, the laminate L1 was punched into a 11.6 inch size (long side 196.4 mm × short side 104 mm). In this processing, the outer peripheral end of the laminated body L1 in a state in which the Thomson blade that performs punching while being in contact with the laminated body L1 applies pressure to the laminated body L1 in the thickness direction of the laminated body L1. The whole was punched to be newly formed. As described above, the double-sided PSA sheet of Example 1 having a laminated structure including a pair of release liners and a double-sided PSA sheet body (adhesive layer) therebetween was produced. The outer peripheral ends of the first and second release liners of the double-sided PSA sheet of Example 1 are in the same position in the sheet in-plane direction. The outer peripheral edge of the pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet of Example 1 was located in the range of 5 to 2000 μm inward from the outer peripheral edges of the first and second release liners in the sheet in-plane direction. In the long side of the double-sided pressure-sensitive adhesive sheet of Example 1, the average of the longest distance and the shortest distance in the separation in the sheet surface direction between the outer peripheral edge of the pressure-sensitive adhesive layer and the outer peripheral edge of the release liner (average separation distance on the long side) Was 47 μm. In the short side of the double-sided pressure-sensitive adhesive sheet of Example 1, the average of the longest distance and the shortest distance in the separation in the sheet surface direction between the outer peripheral edge of the pressure-sensitive adhesive layer and the outer peripheral edge of the release liner (average separation distance on the short side) Was 38 μm.

[Example 2]
Full back processing was performed on the 10 double-sided PSA sheets of Example 1 that were aligned and stacked. Specifically, first, a laminate of 10 double-sided pressure-sensitive adhesive sheets of Example 1 is sandwiched between a pair of holding plates of a vise structure jig in the thickness direction while the outer peripheral edge and the vicinity thereof are exposed. It clamped in the aspect which can apply a pressurization between clamping plates. Then, in a state in which the pressure between the sandwich plates acting in the thickness direction of the laminate is adjusted so that the adhesive derived from the adhesive layer partially bulges to the outside at the outer peripheral edge of the laminate, The entire outer peripheral edge was cut with a cutting amount of 1.0 mm using a rotary blade. Thereafter, the laminate was released from the applied pressure between the sandwiching plates. As described above, a double-sided PSA sheet of Example 2 having a laminated structure including a pair of release liners and a double-sided PSA sheet body (adhesive layer) therebetween was produced. The outer peripheral ends of the first and second release liners of the double-sided PSA sheet of Example 2 are in the same position in the sheet in-plane direction. The outer peripheral edge of the pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet of Example 2 was located in the range of 5 to 2000 μm inward from the outer peripheral edges of the first and second release liners in the in-plane direction of the sheet. In the long side of the double-sided pressure-sensitive adhesive sheet of Example 2, the average of the longest distance and the shortest distance in the separation in the sheet surface direction between the outer peripheral edge of the pressure-sensitive adhesive layer and the outer peripheral edge of the release liner (average separation distance on the long side) Was 170 μm. In the short side of the double-sided pressure-sensitive adhesive sheet of Example 2, the average of the longest distance and the shortest distance in the separation in the sheet surface direction between the outer peripheral edge of the pressure-sensitive adhesive layer and the outer peripheral edge of the release liner (average separation distance on the short side) Was 135 μm.

Example 3
The same as Example 1 except that the acrylic pressure-sensitive adhesive composition C2 was used instead of the acrylic pressure-sensitive adhesive composition C1, and the thickness of the pressure-sensitive adhesive layer formed was changed to 250 μm instead of 500 μm. And the double-sided adhesive sheet of Example 3 which has a laminated structure containing a pair of release liner and the double-sided adhesive sheet main body (adhesive layer) between them was produced. The outer peripheral ends of the first and second release liners of the double-sided PSA sheet of Example 3 are in the same position in the sheet in-plane direction. The outer peripheral edge of the pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet of Example 3 was located in the range of 5 to 2000 μm inward from the outer peripheral edges of the first and second release liners in the sheet in-plane direction. In the long side of the double-sided pressure-sensitive adhesive sheet of Example 3, the average of the longest distance and the shortest distance in the separation in the sheet surface direction between the outer peripheral edge of the pressure-sensitive adhesive layer and the outer peripheral edge of the release liner (average separation distance on the long side) Was 11 μm. In the short side of the double-sided pressure-sensitive adhesive sheet of Example 3, the average of the longest distance and the shortest distance in the separation in the sheet plane direction between the outer peripheral edge of the pressure-sensitive adhesive layer and the outer peripheral edge of the release liner (average separation distance on the short side) Was 13 μm.

Example 4
In the same manner as in Example 2 except that the double-sided pressure-sensitive adhesive sheet of Example 3 was used instead of the double-sided pressure-sensitive adhesive sheet of Example 1, a pair of release liners and a double-sided pressure-sensitive adhesive sheet body (adhesive layer) therebetween were included. A double-sided PSA sheet of Example 4 having a laminated structure was produced. The outer peripheral ends of the first and second release liners of the double-sided PSA sheet of Example 4 are in the same position in the sheet in-plane direction. The outer peripheral edge of the pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet of Example 4 was located in the range of 5 to 2000 μm inward from the outer peripheral edges of the first and second release liners in the in-plane direction of the sheet. In the long side of the double-sided pressure-sensitive adhesive sheet of Example 4, the average of the longest distance and the shortest distance in the in-plane direction separation between the pressure-sensitive adhesive layer outer peripheral edge and the release liner outer peripheral edge (average separation distance on the long side) Was 170 μm. In the short side of the double-sided pressure-sensitive adhesive sheet of Example 4, the average of the longest distance and the shortest distance in the in-plane direction separation between the outer peripheral edge of the pressure-sensitive adhesive layer and the outer peripheral edge of the release liner (average separation distance on the short side) Was 150 μm.

Example 5
<Formation of first adhesive layer>
The acrylic pressure-sensitive adhesive composition C1 is applied onto one side of a base material obtained by corona treatment on both sides of an 80 μm thick polyethylene terephthalate film (trade name “Cosmo Shine SRF”, manufactured by Toyobo Co., Ltd.). A pressure-sensitive adhesive composition layer was formed. Next, a PET-based first release liner (thickness 125 μm, light release type, manufactured by Nitto Denko Corporation) is further laminated on the pressure-sensitive adhesive composition layer, and the pressure-sensitive adhesive composition layer is covered to provide oxygen. Shut off. In this way, a laminate (laminate L2 ′) having a laminate configuration of [first release liner / adhesive composition layer / base material] was obtained. Next, the laminated body L2 ′ was irradiated with ultraviolet rays having an illuminance of 3 mW / cm ² for 300 seconds from the first release liner side using a black light (manufactured by Toshiba Corporation). Thereby, the pressure-sensitive adhesive composition layer of the laminate L2 ′ is cured to form a pressure-sensitive adhesive layer (first pressure-sensitive adhesive layer), and a stack of [first release liner / pressure-sensitive adhesive layer (first pressure-sensitive adhesive layer) / base material]. A laminate (laminate L2) having a configuration was obtained. The thickness of the 1st adhesive layer in the laminated body L2 is 100 micrometers.

<Formation of second adhesive layer>
The acrylic pressure-sensitive adhesive composition C1 was applied onto a PET-based third release liner (thickness 125 μm, light release type, manufactured by Nitto Denko Corporation) to form a pressure-sensitive adhesive composition layer. Next, a PET-based second release liner (thickness 125 μm, heavy release type, manufactured by Nitto Denko Corporation) is further laminated on the pressure-sensitive adhesive composition layer, and the pressure-sensitive adhesive composition layer is covered with oxygen. Shut off. In this way, a laminate (laminate L3 ′) having a laminate configuration of [third release liner / adhesive composition layer / second release liner] was obtained. Next, ultraviolet rays having an illuminance of 3 mW / cm ² were irradiated for 300 seconds from the side of the third release liner to the laminate L3 ′ using a black light (manufactured by Toshiba Corporation). Thus, the pressure-sensitive adhesive composition layer of the laminate L3 ′ is cured to form a pressure-sensitive adhesive layer (second pressure-sensitive adhesive layer), and [third release liner / pressure-sensitive adhesive layer (second pressure-sensitive adhesive layer) / second release liner] A laminated body (laminated body L3) having a laminated structure of The thickness of the 2nd adhesive layer in the laminated body L3 is 500 micrometers.

<Production of double-sided PSA sheet>
After peeling the third release liner from the laminate L3 (third release liner / second pressure-sensitive adhesive layer / second release liner), the second pressure-sensitive adhesive layer with the one-side release liner passes through the surface of the second pressure-sensitive adhesive layer exposed by this peeling. Two adhesive layers were bonded to the exposed surface of the base material of the laminate L2. Thus, a laminate having a laminate configuration of [first release liner / first pressure-sensitive adhesive layer (thickness 100 μm) / base material (thickness 80 μm) / second pressure-sensitive adhesive layer (thickness 500 μm) / second release liner]. A body (laminate L4) was obtained. Next, Thomson processing is performed on the laminate L4 in the same manner as in Example 1, and a pair of release liners and a double-sided pressure-sensitive adhesive sheet main body (first pressure-sensitive adhesive layer / base material / second pressure-sensitive adhesive layer) therebetween. A double-sided PSA sheet of Example 5 having a laminated structure containing The outer peripheral ends of the first and second release liners of the double-sided PSA sheet of Example 5 are in the same position in the sheet in-plane direction. The outer peripheral edge of the pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet of Example 5 was located in the range of 5 to 2000 μm inward from the outer peripheral edges of the first and second release liners in the sheet in-plane direction. In the long side of the double-sided pressure-sensitive adhesive sheet of Example 5, the average of the longest distance and the shortest distance in the separation in the sheet surface direction between the outer peripheral edge of the pressure-sensitive adhesive layer and the outer peripheral edge of the release liner (average separation distance on the long side) Was 53 μm. In the short side of the double-sided pressure-sensitive adhesive sheet of Example 5, the average of the longest distance and the shortest distance in the in-plane direction separation between the outer peripheral edge of the pressure-sensitive adhesive layer and the outer peripheral edge of the release liner (average separation distance on the short side) Was 27 μm.

Example 6
A pair of release liners and a double-sided adhesive sheet body (first adhesive) between the pair of release liners except that 10 double-sided adhesive sheets of Example 5 were used instead of 10 double-sided adhesive sheets of Example 1 The double-sided pressure-sensitive adhesive sheet of Example 6 having a laminated structure including (agent layer / base material / second pressure-sensitive adhesive layer) was produced. The outer peripheral ends of the first and second release liners of the double-sided PSA sheet of Example 6 are in the same position in the sheet in-plane direction. The outer peripheral edge of the pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet of Example 6 was located in the range of 5 to 2000 μm inward from the outer peripheral edges of the first and second release liners in the in-plane direction of the sheet. In the long side of the double-sided pressure-sensitive adhesive sheet of Example 6, the average of the longest distance and the shortest distance in the separation in the sheet surface direction between the outer peripheral edge of the pressure-sensitive adhesive layer and the outer peripheral edge of the release liner (average separation distance on the long side) Was 113 μm. In the short side of the double-sided pressure-sensitive adhesive sheet of Example 6, the average of the longest distance and the shortest distance in the separation in the sheet plane direction between the outer peripheral edge of the pressure-sensitive adhesive layer and the outer peripheral edge of the release liner (average separation distance on the short side) Was 130 μm.

[Comparative Example 1]
A double-sided pressure-sensitive adhesive sheet with a release liner of Comparative Example 1 was produced in the same manner as in Example 1 except that cutting using a cutter knife was performed instead of Thomson processing. At the outer peripheral edge of the double-sided pressure-sensitive adhesive sheet of Comparative Example 1, the pressure-sensitive adhesive layer protruded from between the release liners.

[Comparative Example 2]
A double-sided pressure-sensitive adhesive sheet with a release liner of Comparative Example 2 was prepared in the same manner as in Example 3 except that the cutting process using a cutter knife was performed instead of the Thomson process. At the outer peripheral edge of the double-sided pressure-sensitive adhesive sheet of Comparative Example 2, the pressure-sensitive adhesive layer protruded from between the release liners.

<Storage modulus of adhesive layer>
The storage elastic modulus regarding each adhesive layer in each double-sided adhesive sheet of an Example and a comparative example was calculated | required by the dynamic viscoelasticity measurement. In preparing a measurement sample to be used for dynamic viscoelasticity measurement, first, a necessary number having a laminated configuration of [first release liner / adhesive layer / second release liner] for each pressure-sensitive adhesive layer to be measured. The laminate (laminate L1) was prepared in the same manner as the laminate L1 of Example 1. The thickness of each pressure-sensitive adhesive layer in the required number of laminates L1 prepared for each measurement target is the same as the thickness of the pressure-sensitive adhesive layer to be measured. Next, the release liner was peeled from each of the produced laminates L1, and the pressure-sensitive adhesive layers were sequentially bonded together. In this manner, a laminated pressure-sensitive adhesive layer sheet having a thickness of about 2 mm was prepared for each pressure-sensitive adhesive layer to be measured. Next, this laminated pressure-sensitive adhesive layer sheet was punched out to obtain a cylindrical pellet (diameter 7.9 mm), which was used as a measurement sample. About each produced measurement sample, using a dynamic viscoelasticity measuring apparatus (trade name “ARES”, manufactured by Rheometric Co., Ltd.), the dynamic viscoelasticity measurement is performed after fixing the jig to a 7.9 mm diameter parallel plate. Went. In this measurement, the measurement mode was the shear mode, the measurement temperature range was −70 ° C. to 150 ° C., the temperature increase rate was 5 ° C./min, and the frequency was 1 Hz. Thereby, the temperature dependence of the storage elastic modulus G ′ of each measurement sample was measured. The values of the storage elastic modulus (G ′) at 23 ° C. of each pressure-sensitive adhesive layer in each double-sided pressure-sensitive adhesive sheet of Examples and Comparative Examples are listed in Tables 1 and 2.

<Breakage / Deficiency of the adhesive layer when peeling the release liner>
About each double-sided adhesive sheet of an Example and a comparative example, the presence or absence of the failure | damage or a defect | deletion of the adhesive layer at the time of peeling liner peeling was investigated. Specifically, when a light release type release liner is manually peeled out of a pair of release liners with a double-sided pressure-sensitive adhesive sheet, the case where the adhesive does not adhere to the peeled release liner is good (○) The case where the adhesive was adhered to the peeled release liner was evaluated as defective (x).

[Evaluation]
In the double-sided pressure-sensitive adhesive sheets of Examples 1 to 6 having the configuration of the present invention, any partial breakage or deficiency of the pressure-sensitive adhesive layer during release of the release liner was suppressed. On the other hand, in the double-sided pressure-sensitive adhesive sheets of Comparative Examples 1 and 2, the pressure-sensitive adhesive layer was partially damaged or lost during peeling of the release liner.

X1, X2 adhesive sheet (double-sided adhesive sheet)
10,20 Adhesive sheet body (Double-sided adhesive sheet body)
11 Adhesive Layer 21 Adhesive Layer (First Adhesive Layer)
22 Adhesive layer (second adhesive layer)
11a, 21a, 22a Outer peripheral edge 23 Base material L1 Release liner (first release liner)
L2 release liner (second release liner)
L1a, L2a Outer peripheral edge

Claims (9)

A laminated structure including a first release liner, a second release liner, and a double-sided PSA sheet body having at least one pressure-sensitive adhesive layer and positioned between the first and second release liners;
At least a partial region of the outer peripheral edge of the pressure-sensitive adhesive layer is at a distance of 5 to 2000 μm inward from the outer peripheral edge of the first release liner and the outer peripheral edge of the second release liner in the sheet plane direction. Double-sided adhesive sheet.   2. The outer peripheral edge of the pressure-sensitive adhesive layer is located at a distance of 5 to 2000 μm inward from the outer peripheral edge of the first release liner and the outer peripheral edge of the second release liner in the sheet in-plane direction. Double-sided adhesive sheet.   The double-sided pressure-sensitive adhesive sheet according to claim 1 or 2, wherein the pressure-sensitive adhesive layer has a thickness of 25 µm or more. The double-sided pressure-sensitive adhesive sheet according to any one of claims 1 to 3, wherein a storage elastic modulus at 23 ° C of the pressure-sensitive adhesive layer is 1.0 x 10 ⁴ Pa or more. It has a laminated structure including a first release liner, a second release liner, and a double-sided pressure-sensitive adhesive sheet body positioned between the first and second release liners, and the double-sided pressure-sensitive adhesive sheet body includes a first pressure-sensitive adhesive layer. And a laminated structure including a second pressure-sensitive adhesive layer and a base material positioned between the first and second pressure-sensitive adhesive layers,
At least a part of the outer peripheral edge of the first pressure-sensitive adhesive layer has a distance of 5 to 2000 μm inward from the outer peripheral edge of the first release liner and the outer peripheral edge of the second release liner in the sheet in-plane direction. Yes,
At least a part of the outer peripheral edge of the second pressure-sensitive adhesive layer has a distance of 5 to 2000 μm inward from the outer peripheral edge of the first release liner and the outer peripheral edge of the second release liner in the in-plane direction. There is a double-sided adhesive sheet.   The outer peripheral end of the first pressure-sensitive adhesive layer is at a distance of 5 to 2000 μm inward from the outer peripheral end of the first release liner and the outer peripheral end of the second release liner in the in-plane direction of the sheet. The double-sided pressure-sensitive adhesive sheet described.   The outer peripheral edge of the second pressure-sensitive adhesive layer is at a distance of 5 to 2000 µm inward from the outer peripheral edge of the first release liner and the outer peripheral edge of the second release liner in the in-plane direction of the sheet. 6. The double-sided pressure-sensitive adhesive sheet according to 6.   The double-sided pressure-sensitive adhesive sheet according to any one of claims 5 to 7, wherein a thickness of the first pressure-sensitive adhesive layer and / or a thickness of the second pressure-sensitive adhesive layer is 25 µm or more. The storage elastic modulus at 23 ° C. of the first pressure-sensitive adhesive layer and / or the storage elastic modulus at 23 ° C. of the second pressure-sensitive adhesive layer is 1.0 × 10 ⁴ Pa or more. The double-sided pressure-sensitive adhesive sheet according to any one of the above.

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