Method for manufacturing a double-sided adhesive tape with separator, a chemical solution tank, and a chemical solution tank

Abstract

This invention provides a double-sided adhesive tape with a separator that can suppress cohesive failure (separation) of the adhesive layer due to the peeling of the separator when bonding fluororesins, allowing for easy bonding of fluororesins to cans and other containers, and providing excellent adhesive reliability when bonding fluororesins to cans and other containers. Furthermore, it provides a method for manufacturing a chemical tank using this double-sided adhesive tape with a separator. Finally, it provides a chemical tank to which this double-sided adhesive tape with a separator has been attached. [Solution] A double-sided adhesive tape with a separator, comprising a double-sided adhesive tape having an adhesive layer and a separator on one side of the double-sided adhesive tape, wherein the adhesive layer includes an adhesive layer (Y1) formed using an adhesive composition (X1), the total thickness of the adhesive layers of the double-sided adhesive tape is 300 μm or more and 1500 μm or less, the side of the double-sided adhesive tape having the separator is called surface (a), the side of the double-sided adhesive tape not having the separator is called surface (b), the 180° peel force at 23°C at the interface between surface (a) and the separator is F1, and when surface (b) is attached to the side of the separator that is not in contact with surface (a) of the double-sided adhesive tape, the 180° peel force at 23°C at the interface between surface (b) and the separator is F2, the double-sided adhesive tape with a separator satisfies the following formula (1). F1 / F2≧2.0 (1)

Description

[Technical Field]

[0001] This invention relates to a double-sided adhesive tape with a separator. Furthermore, this invention relates to a method for manufacturing a chemical solution tank using the double-sided adhesive tape with a separator. Moreover, this invention relates to a chemical solution tank to which the double-sided adhesive tape with the separator is attached. [Background technology]

[0002] Conventionally, adhesive tape has been widely used to fix various components. Specifically, for example, adhesive tape is used to adhere a cover panel to protect the surface of a portable electronic device to a touch panel module or display panel module, or to bond a touch panel module to a display panel module. In addition to high adhesiveness, adhesive tape used to fix such components is required to have functions such as heat resistance, thermal conductivity, and impact resistance, depending on the environment in which it is used (for example, Patent Documents 1 to 3). [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2015-052050 [Patent Document 2] Japanese Patent Publication No. 2015-021067 [Patent Document 3] Japanese Patent Publication No. 2015-120876 [Overview of the project] [Problems that the invention aims to solve]

[0004] In recent years, the demand for fluororesins has been increasing in various fields due to their excellent heat resistance, chemical resistance, low dielectric properties, and water repellency. For example, polytetrafluoroethylene (PTFE) is used in a wide range of applications, such as wire insulation and building materials, due to its high mechanical strength and excellent processability.

[0005] In the semiconductor and chemical industries, many chemical solutions such as acids and alkalis are used. When storing or disposing of chemical solutions, lined tanks with fluororesin bonded to the tank body are often used for corrosion prevention purposes. Conventionally, when bonding fluororesin to the tank body, adhesives such as chloroprene rubber and epoxy resin have been used for the fluororesin and the tank body respectively. However, since these adhesives require high-temperature treatments such as a process of drying the solvent after application and before bonding the fluororesin, and a process of thermally curing the adhesive at high temperature, the work efficiency is poor and the construction takes time. Also, in such processes, the solvent and the adhesive itself volatilize during the high-temperature treatment, so the deterioration of the working environment is also a problem. Therefore, an alternative to the adhesive tape that can bond the fluororesin to the tank body without performing high-temperature treatment is desired.

[0006] When bonding fluororesin to the tank body using an adhesive tape instead of an adhesive, the construction is carried out in the order of (i) producing a laminated sheet by laminating a fluororesin sheet and an adhesive tape, and then (ii) laminating the laminated sheet to the tank body. However, the adhesive for laminating to the tank body is a hot-melt adhesive design that emphasizes reworkability for alignment at room temperature and exhibits strong adhesive force when heated. Therefore, during the above (i), the separator on the adhesive layer side laminated to the tank body is likely to peel off, and there is a problem that cohesive failure (crying separation) of the adhesive layer may occur due to the peeling of the separator. Also, in the adhesive tape with separators laminated on both sides, there are problems of deterioration of workability and cost increase due to an increase in the separator peeling process on one side.

[0007] The present invention can suppress the cohesive failure (tearing apart) of the adhesive layer accompanying the separation of the separator when bonding fluororesins, can easily bond the fluororesin and a can body or the like, and provides a double-sided adhesive tape with a separator that has excellent adhesive reliability when the fluororesin and the can body or the like are bonded. Further, the present invention provides a method for manufacturing a chemical solution tank using the double-sided adhesive tape with a separator. Furthermore, the present invention provides a chemical solution tank to which the double-sided adhesive tape in the double-sided adhesive tape with a separator is attached.

Means for Solving the Problems

[0008] The present disclosure 1 is a double-sided adhesive tape with a separator having a double-sided adhesive tape having an adhesive layer and a separator on one surface of the double-sided adhesive tape. The adhesive layer includes an adhesive layer (Y1) formed using an adhesive composition (X1). The total thickness of the adhesive layers of the double-sided adhesive tape is 300 μm or more and 1500 μm or less. The surface of the double-sided adhesive tape having the separator is defined as surface (a), and the surface of the double-sided adhesive tape not having the separator is defined as surface (b). The 180° peel force at 23° C. at the interface between surface (a) and the separator is defined as F1. When surface (b) is bonded to the surface of the separator that is not in contact with surface (a) of the double-sided adhesive tape, and the 180° peel force at 23° C. at the interface between surface (b) and the separator is defined as F2, it is a double-sided adhesive tape with a separator that satisfies the following formula (1). F1 / F2≧2.0 (1) The present disclosure 2 is the double-sided adhesive tape with a separator according to the present disclosure 1, wherein F1 is 150 mN / 50 mm or more and 2000 mN / 50 mm or less. The present disclosure 3 is the double-sided adhesive tape with a separator according to the present disclosure 1 or 2, wherein F2 is 1000 mN / 50 mm or less. The present disclosure is the double-sided adhesive tape with a separator according to the present disclosure 1, 2 or 3, wherein the separator is composed of at least one selected from the group consisting of a polyester resin, a polyolefin resin, and paper. Disclosure 5 is a double-sided adhesive tape with a separator according to Disclosure 1, 2, 3, or 4, wherein the separator has a release layer containing at least one release agent selected from the group consisting of polyolefin-based release agents, silicone-based release agents, and fluororesin-based release agents. Disclosure 6 relates to a double-sided adhesive tape having an adhesive layer and a separator-equipped double-sided adhesive tape having separators on both sides of the double-sided adhesive tape, wherein the adhesive layer includes an adhesive layer (Y1) formed using an adhesive composition (X1), the total thickness of the adhesive layers of the double-sided adhesive tape is 300 μm or more and 1500 μm or less, and the separators on both sides of the separator-equipped double-sided adhesive tape have different magnitudes of 180° peel force at 23°C from the double-sided adhesive tape, the separator with a larger magnitude of 180° peel force is called the first separator, and the separator with a smaller magnitude of 180° peel force is called the second separator, and when the 180° peel force at 23°C between the first separator and the double-sided adhesive tape is F3, and the 180° peel force at 23°C between the second separator and the double-sided adhesive tape is F4, the separator-equipped double-sided adhesive tape satisfies the following formula (2). F3 / F4≧2.0 (2) Disclosure 7 is a double-sided adhesive tape with a separator according to Disclosure 6, wherein F3 is 150mN / 50mm or more and 2000mN / 50mm or less. Disclosure 8 is a double-sided adhesive tape with a separator according to Disclosure 6 or 7, wherein the above F4 is 1000 mN / 50 mm or less. Disclosure 9 is a double-sided adhesive tape with separators according to Disclosure 6, 7, or 8, wherein the first separator and the second separator are each independently composed of at least one selected from the group consisting of polyester resin, polyolefin resin, and paper. Disclosure 10 is a double-sided adhesive tape with separators according to Disclosure 6, 7, 8, or 9, wherein the first separator and the second separator each independently have a release layer containing at least one release agent selected from the group consisting of polyolefin-based release agents, silicone-based release agents, and fluororesin-based release agents. Disclosure 11 is a double-sided adhesive tape with a separator according to Disclosure 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10, wherein the adhesive composition (X1) contains a base polymer, and the base polymer comprises at least one selected from the group consisting of (meth)acrylic copolymers and styrene-based elastomers. Disclosure 12 is a double-sided adhesive tape with a separator according to Disclosure 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or 11, wherein the adhesive composition (X1) further contains a tackifying resin (T1). Disclosure 13 is a double-sided adhesive tape with a separator according to Disclosure 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12, wherein the adhesive layer (Y1) has a 180° peel force of 50 N / 25 mm or more against SUS at 23°C. Disclosure 14 is a double-sided adhesive tape with a separator according to Disclosure 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, or 13, wherein the adhesive layer further comprises an adhesive layer (Y2) formed using an adhesive composition (X2). Disclosure 15 is a double-sided adhesive tape with a separator according to Disclosure 14, wherein the adhesive composition (X2) contains a base polymer, and the base polymer comprises at least one selected from the group consisting of (meth)acrylic copolymers and styrene-based elastomers. Disclosure 16 is a double-sided adhesive tape with a separator according to Disclosure 14 or 15, wherein the adhesive composition (X2) further contains a tackifying resin (T2). Disclosure 17 is a double-sided adhesive tape with a separator according to Disclosure 16, in which the tackifying resin (T2) comprises a tackifying resin (T2-1) having at least one constituent unit (A) selected from the group consisting of constituent units (A-1), (A-1'), (A-2), (A-2'), (A-3), (A-3'), (A-4), and (A-4') represented by the following formula. Disclosure 18 is a double-sided adhesive tape with a separator according to Disclosure 14, 15, 16, or 17, wherein the adhesive layer (Y2) has a 180° peel strength of 5.0 N / 25 mm or more against polytetrafluoroethylene (PTFE) at 23°C. Disclosure 19 is a double-sided adhesive tape with a separator according to Disclosure 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, or 18, wherein the double-sided adhesive tape further comprises a base material, the base material containing at least one selected from the group consisting of polyester resin, polyimide resin, polyether resin, polyolefin resin, polyurethane resin, metal, glass fiber, and carbon fiber. Disclosure 20 is a double-sided adhesive tape with a separator according to Disclosure 19, wherein the ratio of the thickness of the base material to the thickness of the double-sided adhesive tape is 35% or less. Disclosure 21 is a double-sided adhesive tape with separators, as described in Disclosures 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20, used for lining the can body in a chemical tank. Disclosure 22 is a method for manufacturing a chemical tank, comprising: a lining sheet manufacturing step of pressing a sheet containing fluororesin onto the adhesive layer (Y2) of a double-sided adhesive tape with a separator according to Disclosure 14, 15, 16, 17, or 18; a separator peeling step of peeling off the separator on the adhesive layer (Y1) side of the lining sheet manufactured in the lining sheet manufacturing step to expose the adhesive layer (Y1); and a lining sheet bonding step of bonding the adhesive layer (Y1) to the inside of the tank body of the chemical tank. Disclosure 23 is a chemical tank in which the double-sided adhesive tape with separator of Disclosure 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, or 21 is attached to the inner surface of a can.

[0009] [ka]

[0010] [ka]

[0011] [ka]

[0012] [ka]

[0013] In the formula, R 1 ~R 7 * represents a hydrogen atom, an aliphatic hydrocarbon group, an aromatic hydrocarbon group, a polar functional group, an aliphatic hydrocarbon group having a polar functional group, or an aromatic hydrocarbon group having a polar functional group, respectively. n and l each represent an integer between 2 and 4, and n' and l' each represent an integer between 2 and 5. m and k each represent an integer between 1 and 4, and m' and k' each represent an integer between 1 and 5. * represents a linking part. The present invention will be described in detail below. Furthermore, the double-sided adhesive tape with separator described in Disclosure 1 is also referred to as "the double-sided adhesive tape with separator of Invention 1," and the double-sided adhesive tape with separator described in Disclosure 6 is also referred to as "the double-sided adhesive tape with separator of Invention 2." In addition, matters common to the double-sided adhesive tape with separator of Invention 1 and the double-sided adhesive tape with separator of Invention 2 are either not specifically specified or are described as "the double-sided adhesive tape with separator of the present invention."

[0014] The inventors have investigated the following: a double-sided adhesive tape having an adhesive layer formed using an adhesive composition, and a double-sided adhesive tape with a separator having a separator on one side of the double-sided adhesive tape. They have adjusted the total thickness of the adhesive layer of the double-sided adhesive tape to a specific range, defining the side of the double-sided adhesive tape with the separator as surface (a) and the side of the double-sided adhesive tape without the separator as surface (b), defining the 180° peel force at 23°C at the interface between surface (a) and the separator as F1, and when surface (b) is attached to the side of the separator that is not in contact with surface (a) of the double-sided adhesive tape, they have investigated the following: the value of F1 relative to F2 is defined as being greater than or equal to a specific value. As a result, we discovered that it is possible to suppress the cohesive breakdown (separation) of the adhesive layer due to the peeling of the separator when bonding fluororesins, and that it is possible to obtain a double-sided adhesive tape with a separator that can easily bond fluororesins to cans and the like, thus completing the present invention. Furthermore, the inventors have investigated the following: a double-sided adhesive tape having an adhesive layer and a double-sided adhesive tape with a separator having separators on both sides of the double-sided adhesive tape; adjusting the total thickness of the adhesive layer of the double-sided adhesive tape to a specific range; and making the separators on both sides of the double-sided adhesive tape with a separator different in magnitude of 180° peel force at 23°C from the double-sided adhesive tape; designating the separator with a larger 180° peel force as the first separator and the separator with a smaller 180° peel force as the second separator; defining the 180° peel force at 23°C between the first separator and the double-sided adhesive tape as F3; and defining the 180° peel force at 23°C between the second separator and the double-sided adhesive tape as F4; and considering that the value of F4 relative to F3 is greater than or equal to a specific value. As a result, we discovered that it is possible to suppress the cohesive breakdown (separation) of the adhesive layer due to the peeling of the separator when bonding fluororesins, and that it is possible to obtain a double-sided adhesive tape with a separator that can easily bond fluororesins to cans and the like, thus completing the present invention.

[0015] The double-sided adhesive tape with separator of the present invention has a separator. It is preferable that the separator has a release layer on at least one side. Having a release layer on at least one side of the separator makes it easier to reduce the 180° peel force between the separator and the double-sided adhesive tape, and makes it easier to adjust F1 / F2 and F3 / F4, which will be described later, to a preferred range. From the viewpoint of enabling lamination with a single-sided separator configuration, it is more preferable that the separator has release layers on both sides.

[0016] In this specification, the term "release layer" includes not only a layer on the surface of the separator substrate that has been treated with a release agent, but also a layer that has release properties even if it has not been treated with a release agent on its surface. Examples of the above-mentioned mold release treatments include corona treatment, plasma treatment, sandblasting, chemical etching, and application of mold release agents such as silicone-based release agents. Examples of layers that have release properties even without the above-mentioned release treatment include polyolefin resin layers and fluororesin layers.

[0017] Preferably, the separator has a release layer containing at least one release agent selected from the group consisting of polyolefin-based release agents, silicone-based release agents, and fluororesin-based release agents. In the double-sided adhesive tape with separator of the present invention, by having a release layer containing at least one release agent selected from the group consisting of polyolefin-based release agents, silicone-based release agents, and fluororesin-based release agents, appropriate release properties can be imparted to the adhesive layer.

[0018] Examples of the polyolefin-based release agents mentioned above include release agents containing polyethylene, polypropylene, ethylene-vinyl acetate copolymer (EVA), etc. A commercially available example is RA-80 (manufactured by Ashio Sangyo Co., Ltd.). Examples of the above-mentioned silicone-based release agents include release agents containing polyorganosiloxanes, and commercially available examples include LTC752 (manufactured by Toray Dow Corning) and KS-847 (manufactured by Shin-Etsu Silicone Co., Ltd.). Examples of the above-mentioned fluororesin-based release agents include release agents containing polyorganosiloxanes having fluorine-containing functional groups in their side chains, and commercially available examples include SYL-OFF 7785 (manufactured by Toray Dow Corning).

[0019] Alternatively, the above-mentioned mold release agent may be a prepared one. The method for preparing the above-mentioned release agent is not particularly limited and can be prepared by conventionally known methods. Specifically, for example, a method for preparing a silicone-based release agent includes adding a silicone composition that serves as the base polymer, a release additive to adjust the release force, and a curing catalyst to a solvent and stirring. At this time, F1 and F2 can be adjusted by adjusting the type and content of the release additive. Furthermore, a separator having a release layer can be produced by coating the prepared release agent described above onto the surface of the separator described above and then drying it.

[0020] The thickness of the above-mentioned release layer has a preferred lower limit of 0.02 μm and a preferred upper limit of 1 μm. A thickness of 0.02 μm or more in the release layer makes it easier to reduce the 180° peel force between the separator and the double-sided adhesive tape. A thickness of 1 μm or less in the release layer allows the separator and the adhesive layer of the double-sided adhesive tape to have the necessary adhesion to protect the adhesive layer. A more preferred lower limit in the release layer is 0.05 μm, and a more preferred upper limit is 0.5 μm. Furthermore, by adjusting the thickness of the release layer for each separator, it becomes easier to adjust F1 / F2 and F3 / F4, which will be described later, to a desirable range.

[0021] In the double-sided adhesive tape with separator of the present invention, it is preferable that the separator is composed of at least one material selected from the group consisting of polyester resin, polyolefin resin, and paper. By being composed of at least one material selected from the group consisting of polyester resin, polyolefin resin, and paper, the separator has excellent resistance to the heat and tension applied during tape manufacturing, and thermal shrinkage and damage of the separator can be prevented.

[0022] Examples of separators made from the above-mentioned polyester resin include polyethylene terephthalate (PET) film, polyethylene-2,6-naphthalate (PEN) film, polybutylene terephthalate (PBT) film, polypropylene terephthalate (PPT) film, or films made from copolymers mainly composed of the constituent components of these resins. Examples of separators made from the above-mentioned polyolefin resin include polypropylene film, polyethylene film, polyethylene-vinyl acetate copolymer (EVA) film, and the like. Examples of separators made from the above-mentioned paper include kraft paper, fine paper, and glassine paper.

[0023] The thickness of the separator described above has a preferred lower limit of 15 μm and a preferred upper limit of 100 μm. A separator thickness of 15 μm or more ensures that the separator and the adhesive layer of the double-sided adhesive tape have the necessary adhesion to protect the adhesive layer. A release layer thickness of 100 μm or less makes it easier to reduce the 180° peel force between the separator and the double-sided adhesive tape, thereby further suppressing the peeling of the adhesive layer in contact with the fluororesin-containing sheet when the separator is removed. A more preferred lower limit of 23 μm and a more preferred upper limit of 75 μm is used for the release layer thickness.

[0024] The double-sided adhesive tape with separator according to Invention 1 comprises a double-sided adhesive tape having an adhesive layer and a separator on one side of the double-sided adhesive tape. If the adhesive layer has an adhesive layer (Y2) described later, it is preferable that the double-sided adhesive tape with separator according to Invention 1 has the separator on the side of the adhesive layer (Y1) described later.

[0025] In the double-sided adhesive tape with separator, the side having the separator and the double-sided adhesive tape is referred to as surface (a), and the side of the double-sided adhesive tape without the separator is referred to as surface (b). Let F1 be the 180° peeling force at 23°C at the interface between surface (a) and the separator. When surface (b) is attached to the surface of the separator that is not in contact with surface (a) of the double-sided adhesive tape, and the 180° peel force at 23°C at the interface between surface (b) and the separator is F2, the following equation (1) is satisfied. F1 / F2≧2.0 (1) The double-sided adhesive tape with separator according to Invention 1 satisfies the above formula (1), making it possible to suppress the cohesive breakdown (separation) of the adhesive layer due to the peeling of the separator when bonding fluororesin to a can or the like, and making it possible to easily bond the fluororesin to the can or the like. Furthermore, when the double-sided adhesive tape with separator according to Invention 1 is rolled up, the adhesion between the adhesive layer, which does not have a separator laminated as the innermost layer of the double-sided adhesive tape in the roll structure, and the separator, which is the outermost layer, becomes relatively weak, making it easier to use. The preferred lower limit for F1 / F2 is 4.0, and the more preferred lower limit is 5.0. Furthermore, if F1 is extremely large, the separator's peelability will be poor, and if F2 is extremely small, the separator will peel off before use. Therefore, from the viewpoint of balancing the peeling forces of both, the preferred upper limit for F1 / F2 is 40, and the more preferred upper limit is 30.

[0026] The preferred lower limit of F1 is 150 mN / 50 mm, and the preferred upper limit is 2000 mN / 50 mm. When F1 is 150 mN / 50 mm or higher, the separator has the necessary peeling force to protect the adhesive layer. Therefore, when bonding the fluororesin to a can or the like, the peeling of the separator from the adhesive layer and the cohesive failure (separation) of the adhesive layer due to the peeling of the separator can be suppressed, making it easier to bond the fluororesin to the can or the like. When F1 is 2000 mN / 50 mm or lower, the separator is not too hard, and the problem of the separator being unable to peel off the adhesive layer during use can be suppressed. A more preferable lower limit for F1 is 250 mN / 50 mm, and a more preferable upper limit is 1600 mN / 50 mm. The following are some examples of methods for measuring F1 as described above. Specifically, first, the side of the double-sided adhesive tape with separator according to Invention 1 that does not have a separator laminated on it is backed with a 23 μm thick biaxially oriented PET film, and then cut to a size of 50 mm wide and 100 mm long to prepare a test specimen. Next, the prepared test specimen can be measured by peeling the separator from the double-sided adhesive tape at a 180° angle using a tensile testing machine (such as Shimadzu Corporation's "Autograph") in accordance with JIS Z0237, under conditions of 23°C and a peeling speed of 300 mm / min.

[0027] The preferred upper limit for F2 is 1000 mN / 50 mm. Having F2 at or below 1000 mN / 50 mm makes it easier to use the double-sided adhesive tape with separator according to Invention 1 when it is rolled up. A more preferred upper limit for F2 is 500 mN / 50 mm. Furthermore, a preferred lower limit for F2 is 30mN / 50mm. When F2 is 30mN / 50mm or higher, when the separator-equipped double-sided adhesive tape of the present invention 1 is rolled up, the adhesive layer, which is the innermost layer of the double-sided adhesive tape in the roll structure and does not have a separator layer, and the outermost layer, which is the separator, will have appropriate adhesion, making it possible to easily roll up the separator-equipped double-sided adhesive tape of the present invention 1. A more preferred lower limit for F2 is 50mN / 50mm. The following are some examples of methods for measuring F2. Specifically, first, the separator of the double-sided adhesive tape with separator according to Invention 1 is peeled off, and the exposed adhesive surface is backed with a 23 μm thick biaxially oriented PET film. Next, the opposite adhesive surface is attached to the back surface of the peeled separator (a different surface from the separator surface that the backing adhesive layer was in contact with before the separator was peeled off), and then cut to a size of 50 mm wide and 100 mm long to prepare a test piece. Then, the prepared test piece can be measured by peeling the separator from the double-sided adhesive tape at a 180° angle using a tensile testing machine (such as Shimadzu Corporation's "Autograph") in accordance with JIS Z0237, under conditions of 23°C and a peeling speed of 300 mm / min.

[0028] In the double-sided adhesive tape with separator according to Invention 1, it is preferable that the separator is composed of at least one material selected from the group consisting of polyester resin, polyolefin resin, and paper. By being composed of at least one material selected from the group consisting of polyester resin, polyolefin resin, and paper, the separator has excellent resistance to the heat and tension applied during tape manufacturing, and thermal shrinkage and damage of the separator can be prevented.

[0029] In the double-sided adhesive tape with separator according to the present invention 1, examples of separators made of polyester resin, separators made of polyolefin resin, and separators made of paper include those similar to the separators described above.

[0030] In the double-sided adhesive tape with separator according to Invention 1, it is preferable that the separator has a release layer containing at least one release agent selected from the group consisting of polyolefin-based release agents, silicone-based release agents, and fluororesin-based release agents. In the double-sided adhesive tape with separator according to Invention 1, by having a release layer containing at least one release agent selected from the group consisting of polyolefin-based release agents, silicone-based release agents, and fluororesin-based release agents, appropriate release properties can be imparted to the adhesive layer.

[0031] In the double-sided adhesive tape with separator according to Invention 1, examples of the polyolefin-based release agent, the silicone-based release agent, and the fluororesin-based release agent include those similar to the release agents described above.

[0032] The double-sided adhesive tape with separator according to the present invention 2 comprises a double-sided adhesive tape having an adhesive layer and separators on both sides of the double-sided adhesive tape.

[0033] The double-sided adhesive tape with separators of the present invention 2 is such that the separators on both sides of the double-sided adhesive tape have different magnitudes of 180° peel force at 23°C from the double-sided adhesive tape, with the separator having a larger magnitude of 180° peel force being designated as the first separator and the separator having a smaller magnitude of 180° peel force being designated as the second separator, and when the 180° peel force at 23°C between the first separator and the double-sided adhesive tape is denoted as F3, and the 180° peel force at 23°C between the second separator and the double-sided adhesive tape is denoted as F4, the following equation (2) is satisfied. F3 / F4≧2.0 (2) The double-sided adhesive tape with separator according to the present invention 6 satisfies formula (2) above, making it possible to suppress cohesive failure (separation) of the adhesive layer due to the peeling of the separator when bonding fluororesin to a can or the like, and enabling easy bonding of fluororesin to a can or the like. If the above double-sided adhesive tape has an adhesive layer (Y2) described later, it is preferable that the 180° peel force on the adhesive layer (Y1) side is F3 and the 180° peel force on the adhesive layer (Y2) side is F4. The preferred lower limit for F3 / F4 is 4.0, and the more preferred lower limit is 5.0. Furthermore, if F3 is extremely large, the separator's peelability will be poor, and if F4 is extremely small, the separator will peel off before use. Therefore, from the viewpoint of balancing the peeling forces of both, the preferred upper limit for F3 / F4 is 40, and the more preferred upper limit is 30.

[0034] The preferred lower limit of F3 is 150 mN / 50 mm, and the preferred upper limit is 2000 mN / 50 mm. When F3 is 150 mN / 50 mm or higher, the separator has the necessary peeling force to protect the adhesive layer. Therefore, when bonding the fluororesin to a can or the like, the peeling of the separator from the adhesive layer can be further suppressed, and the fluororesin and the can or the like can be bonded more easily. When F3 is 2000 mN / 50 mm or lower, the separator is not too hard, and the problem of the separator not being able to peel off from the adhesive layer during use can be suppressed. A more preferable lower limit for F3 is 250 mN / 50 mm, and a more preferable upper limit is 1600 mN / 50 mm. The following are some examples of methods for measuring F3. Specifically, first, the side of the double-sided adhesive tape with separator according to the present invention 2 on which the second separator is laminated is backed with a biaxially oriented PET film with a thickness of 23 μm, and then cut to a size of 50 mm in width and 100 mm in length to prepare a test specimen. Next, the prepared test specimen can be measured by peeling the first separator from the double-sided adhesive tape at a 180° angle using a tensile testing machine (such as Shimadzu Corporation's "Autograph") in accordance with JIS Z0237, under conditions of 23°C and a peeling speed of 300 mm / min.

[0035] The preferred upper limit for F4 is 1000 mN / 50 mm. By keeping F4 below 1000 mN / 50 mm, the separator is not too hard, and the problem of the separator being unable to peel off the adhesive layer during use can be prevented. A more preferred upper limit for F4 is 500 mN / 50 mm. Furthermore, the preferred lower limit for F4 is 30mN / 50mm. When F4 is 30mN / 50mm or higher, the separator has sufficient peel strength to protect the adhesive layer. A more preferred lower limit for F4 is 50mN / 50mm. Furthermore, the following methods are examples of methods for measuring F4 as described above. Specifically, first, the first separator of the laminated sheet in the wound body of the present invention 2 is peeled off, the exposed adhesive surface is backed with a biaxially oriented PET film with a thickness of 23 μm, and then cut to a size of 50 mm in width and 100 mm in length to prepare a test specimen. Next, the prepared test specimen can be measured by peeling the second separator from the double-sided adhesive tape at a 180° angle using a tensile testing machine (such as Shimadzu Corporation's "Autograph") in accordance with JIS Z0237, under conditions of 23°C and a peeling speed of 300 mm / min.

[0036] Methods for adjusting F1, F2, F3, and F4 above include introducing a release layer to the separator, adjusting the thickness of the release layer, changing the composition of the adhesive layer described later (for example, adding a tackifying resin), adjusting the thickness of the adhesive layer described later (for example, increasing the thickness of the adhesive layer to increase the 180° peeling force), and, in the double-sided adhesive tape with separator of the present invention 2, using different types of separators on each side. Furthermore, by individually adjusting F1, F2, F3, and F4, F1 / F2 and F3 / F4 can be adjusted to an appropriate range.

[0037] In the double-sided adhesive tape with separators of the present invention 2, it is preferable that the first separator and the second separator are each independently composed of at least one material selected from the group consisting of polyester resin, polyolefin resin, and paper. By composing the separators of at least one material selected from the group consisting of polyester resin, polyolefin resin, and paper, excellent resistance to heat and tension applied during tape manufacturing can be achieved, preventing thermal shrinkage and damage to the separators. In particular, from the viewpoint of making it easier to adjust F3 / F4 to a more appropriate range, it is preferable to use different types of separators for the first separator and the second separator.

[0038] In the double-sided adhesive tape with separator according to the present invention 2, the separator made of the polyester resin, the separator made of the polyolefin resin, and the separator made of the paper are, for example, the same as the separator in the double-sided adhesive tape with separator according to the present invention 1.

[0039] In the double-sided adhesive tape with separator according to Invention 2, it is preferable that the first separator and the second separator each independently have a release layer containing at least one release agent selected from the group consisting of polyolefin-based release agents, silicone-based release agents, and fluororesin-based release agents. In the double-sided adhesive tape with separator according to Invention 6, by having a release layer containing at least one release agent selected from the group consisting of polyolefin-based release agents, silicone-based release agents, and fluororesin-based release agents, the separator can be given appropriate release properties and can be easily peeled off from the adhesive layer.

[0040] In the double-sided adhesive tape with separator according to Invention 2, examples of the polyolefin-based release agent, the silicone-based release agent, and the fluororesin-based release agent include those similar to the release agent in the double-sided adhesive tape with separator according to Invention 1.

[0041] The double-sided adhesive tape with separator of the present invention has a double-sided adhesive tape. The above-mentioned double-sided adhesive tape has an adhesive layer. The adhesive layer of the above-mentioned double-sided adhesive sheet may be one layer or two or more layers. The total thickness of the adhesive layer of the above double-sided adhesive tape has a lower limit of 300 μm and an upper limit of 1500 μm. A total thickness of 300 μm or more of the adhesive layer of the above double-sided adhesive tape provides excellent adhesive strength, and the separator-equipped double-sided adhesive tape of the present invention exhibits excellent adhesive reliability when bonding fluororesin to a can or the like. A total thickness of 1500 μm or less of the adhesive layer of the above double-sided adhesive tape reduces the manufacturing cost of the separator-equipped double-sided adhesive tape of the present invention. The preferred lower limit of the total thickness of the adhesive layer of the above double-sided adhesive tape is 350 μm, the preferred upper limit is 1200 μm, the more preferred lower limit is 400 μm, and the more preferred upper limit is 1000 μm.

[0042] The above adhesive layer includes an adhesive layer (Y1) formed using an adhesive composition (X1). From the viewpoint of ease of bonding, the adhesive layer (Y1) is preferably a low-tack adhesive layer. Since the adhesive layer (Y1) is a low-tack adhesive layer, stickiness of the adhesive layer (Y1) can be suppressed, and the resulting double-sided adhesive tape will have superior bonding workability.

[0043] The preferred lower limit of the probe tack value (hereinafter also referred to as "the probe tack value of the adhesive layer (Y1) at 23°C") measured under the conditions of 23°C, applied pressure of 98 gf, applied speed of 100 mm / sec, applied time of 10 seconds, and release speed of 5 mm / sec is 20 N / 5 mmφ. A probe tack value of 20 N / 5 mmφ or higher for the adhesive layer (Y1) at 23°C provides adequate adhesive strength, making it easier to adjust the application position of the double-sided adhesive tape, thus improving the workability of the bonding process. A more preferred lower limit for the probe tack value of the adhesive layer (Y1) at 23°C is 22 N / 5 mmφ. Furthermore, the preferred upper limit of the probe tack value of the adhesive layer (Y1) at 23°C is 25N / 5mmφ. By having a probe tack value of the adhesive layer (Y1) at 23°C of 25N / 5mmφ or less, the stickiness of the adhesive layer (Y1) can be suppressed, and the double-sided adhesive tape will have superior bonding workability. The more preferred upper limit of the probe tack value of the adhesive layer (Y1) at 23°C is 23N / 5mmφ. The probe tack value of the adhesive layer (Y1) at 23°C can be measured by a probe tack test in accordance with JIS Z 3284. Specifically, for example, a test piece can be prepared by cutting the above-mentioned double-sided adhesive tape to a size of 30 mm in width and 30 mm in length. The probe tack test can then be performed on the adhesive layer (Y1) of the prepared test piece using a probe tack tester (RHESCA, "TAC-2," etc.) under the following conditions: 23°C, pressurized pressure of 98 gf, pressurization speed of 100 mm / sec, pressurization time of 10 seconds, and release speed of 5 mm / sec. Furthermore, in this specification, the term "adhesion" refers not only to a permanent bonding phenomenon but also to a temporary bonding phenomenon called "tackiness."

[0044] Methods for adjusting the probe tack value of the adhesive layer (Y1) at 23°C include changing the composition and content ratio of the base polymer (P1) and the tackifying resin (T1) described later, and changing the thickness of the adhesive layer (Y1).

[0045] The adhesive layer (Y1) preferably contains a base polymer (P1). The base polymer (P1) described above preferably contains at least one selected from the group consisting of (meth)acrylic copolymer, styrene elastomer, ethylene-vinyl acetate copolymer, chloroprene rubber, nitrile rubber, polyurethane resin, polyamide resin, polyolefin resin, polyester resin, epoxy resin, and silicone resin. In particular, from the viewpoint of making it easier to adjust the probe tack value of the adhesive layer (Y1) at 23°C and from the viewpoint of improving the heat resistance of the adhesive layer (Y1), it is preferable to include at least one selected from the group consisting of (meth)acrylic copolymer and styrene elastomer. Furthermore, from the viewpoint of suppressing contamination of the adherend, it is preferable that the base polymer (P1) is a base polymer other than silicone resin. In this specification, the term "base polymer" refers to a polymer that accounts for 50% by mass or more of the polymers with a weight-average molecular weight of 50,000 or more contained in the adhesive composition. Furthermore, in this specification, "(meth)acrylic" means acrylic or methacrylic.

[0046] The above (meth)acrylic copolymer preferably has constituent units derived from alkyl (meth)acrylate. The alkyl (meth)acrylate described above preferably includes an alkyl (meth)acrylate having an alkyl group with 4 to 12 carbon atoms at its ester terminus. That is, the (meth)acrylic copolymer preferably has structural units derived from an alkyl (meth)acrylate having an alkyl group with 4 to 12 carbon atoms at its ester terminus. By having structural units derived from an alkyl (meth)acrylate having an alkyl group with 4 to 12 carbon atoms at its ester terminus, the glass transition temperature (Tg) of the (meth)acrylic copolymer is further reduced. As a result, the flexibility of the adhesive layer (Y1) is further improved, and the adhesion strength of the adhesive layer (Y1) to the fluororesin is further improved. In this specification, "(meth)acrylate" means acrylate or methacrylate. Furthermore, in this specification, the term "alkyl (meth)acrylate having an alkyl group at the ester terminus" means a (meth)acrylate in which an alkyl group is bonded to the oxygen atom of the ester bond.

[0047] Examples of alkyl (meth)acrylates having an alkyl group with 4 to 12 carbon atoms at the ester terminus include n-butyl (meth)acrylate, tert-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-hexyl (meth)acrylate, n-heptyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, n-nonyl (meth)acrylate, isononyl (meth)acrylate, 1-methylheptyl (meth)acrylate, and lauryl (meth)acrylate. In particular, since the resulting double-sided adhesive tape has superior adhesion (especially to fluororesins), it is preferable that the alkyl (meth)acrylate having an alkyl group with 4 to 12 carbon atoms at the ester terminus includes alkyl (meth)acrylates having an alkyl group with 6 to 8 carbon atoms at the ester terminus. The alkyl (meth)acrylates having an alkyl group with 4 to 12 carbon atoms at the ester terminus may be used alone or in combination of two or more types.

[0048] The preferred lower limit for the content of constituent units derived from alkyl (meth)acrylate having an alkyl group with 4 to 12 carbon atoms at its ester terminus in the above (meth)acrylic copolymer is 50% by mass. When the content of constituent units derived from alkyl (meth)acrylate having an alkyl group with 4 to 12 carbon atoms at its ester terminus is 50% by mass or more, the glass transition temperature (Tg) of the above (meth)acrylic copolymer is further reduced, and as a result the flexibility of the adhesive layer (Y1) is further improved, thus improving the workability of the resulting double-sided adhesive sheet when bonded. In addition, the adhesive strength of the adhesive layer (Y1) to the fluororesin is also further improved. A more preferred lower limit for the content of constituent units derived from alkyl (meth)acrylate having an alkyl group with 4 to 12 carbon atoms at its ester terminus is 90% by mass, and an even more preferred lower limit is 95% by mass. In particular, the preferred lower limit for the content of constituent units derived from alkyl (meth)acrylate having an alkyl group with 6 to 8 carbon atoms at its ester terminus in the above (meth)acrylic copolymer is 50% by mass, a more preferred lower limit is 85% by mass, and an even more preferred lower limit is 90% by mass. Furthermore, from the viewpoint of the bulk cohesive force of the adhesive layer (Y1), the preferred upper limit for the content of constituent units derived from alkyl (meth)acrylate having an alkyl group with 4 to 12 carbon atoms at the ester terminus is 99.5% by mass, and the more preferred upper limit is 99% by mass.

[0049] The alkyl (meth)acrylate described above may include other alkyl (meth)acrylates other than the alkyl (meth)acrylate having an alkyl group with 4 to 12 carbon atoms at its ester terminus. Examples of the other alkyl (meth)acrylates include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, myristyl (meth)acrylate, cetyl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, ester of 5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)octanol-1 and (meth)acrylic acid, ester of an alcohol with a total of 18 carbon atoms having 1 or 2 methyl groups in a linear main chain and (meth)acrylic acid, behenyl (meth)acrylate, arachidyl (meth)acrylate, and the like. The above-mentioned other alkyl (meth)acrylates may be used individually or in combination of two or more types.

[0050] The (meth)acrylic copolymer preferably further contains structural units derived from a polar functional group-containing monomer. The presence of structural units derived from a polar functional group-containing monomer in the (meth)acrylic copolymer increases the bulk cohesive strength of the adhesive layer (Y1), resulting in a double-sided adhesive tape with superior adhesion.

[0051] The above polar functional group is reactive, such as through crosslinking reactions, and preferably at least one selected from the group consisting of carboxyl groups, hydroxyl groups, amino groups, and epoxy groups. In particular, one selected from the group consisting of carboxyl groups and hydroxyl groups is more preferred because it can contribute to improving the adhesive strength of the resulting adhesive tape. That is, it is preferable that the (meth)acrylic copolymer has at least one structural unit selected from the group consisting of a structural unit derived from a polar functional group-containing monomer (carboxyl group-containing monomer) having a carboxyl group as the above polar functional group, and a structural unit derived from a polar functional group-containing monomer (hydroxyl group-containing monomer) having a hydroxyl group as the above polar functional group. Examples of the above-mentioned carboxyl group-containing monomers include (meth)acrylic acid. Examples of the hydroxyl group-containing monomers mentioned above include 4-hydroxybutyl (meth)acrylate and 2-hydroxyethyl (meth)acrylate. Examples of polar functional group-containing monomers (epoxy group-containing monomers) having an epoxy group as the polar functional group include glycidyl (meth)acrylate. The above-mentioned monomers containing polar functional groups may be used individually or in combination of two or more types.

[0052] In the above (meth)acrylic copolymer, the preferred lower limit for the content of constituent units derived from the carboxyl group-containing monomer is 0.01% by mass, and the preferred upper limit is 3.0% by mass. By having the content of constituent units derived from the carboxyl group-containing monomer within this range, the cohesive force of the bulk of the adhesive layer (Y1) can be appropriately adjusted, resulting in a double-sided adhesive tape with superior adhesion. A more preferred lower limit for the content of constituent units derived from the carboxyl group-containing monomer is 0.05% by mass, and a more preferred upper limit is 2.0% by mass.

[0053] In the above (meth)acrylic copolymer, the preferred lower limit for the content of constituent units derived from the above hydroxyl group-containing monomer is 0.01% by mass, and the preferred upper limit is 3.0% by mass. By having the content of constituent units derived from the above hydroxyl group-containing monomer within this range, the cohesive force of the bulk of the adhesive layer (Y1) can be appropriately adjusted, resulting in a double-sided adhesive tape with superior adhesion. A more preferred lower limit for the content of constituent units derived from the above hydroxyl group-containing monomer is 0.05% by mass, and a more preferred upper limit is 2.0% by mass.

[0054] In the above (meth)acrylic copolymer, the preferred lower limit for the total content of constituent units derived from the above polar functional group-containing monomer is 0.01% by mass, and the preferred upper limit is 6.0% by mass. By having the total content of constituent units derived from the above polar functional group-containing monomer within this range, the cohesive force of the bulk of the adhesive layer (Y1) can be appropriately adjusted, resulting in a double-sided adhesive tape with superior adhesion. A more preferred lower limit for the total content of constituent units derived from the above polar functional group-containing monomer is 0.1% by mass, and a more preferred upper limit is 3.0% by mass.

[0055] The above (meth)acrylic copolymer may optionally contain structural units derived from other copolymerizable monomers other than the alkyl (meth)acrylate and the polar functional group-containing monomer. Examples of other monomers mentioned above include benzyl (meth)acrylate, 2-butoxyethyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, and polypropylene glycol mono(meth)acrylate. In addition, other monomers that can be used include vinyl carboxylates such as vinyl acetate and various monomers commonly used in acrylic polymers such as styrene. The other monomers mentioned above may be used individually or in combination of two or more.

[0056] The preferred lower limit for the weight-average molecular weight (Mw) of the above (meth)acrylic copolymer is 50,000, and the preferred upper limit is 1,600,000. A weight-average molecular weight (Mw) of 50,000 or more improves the bulk cohesive strength of the adhesive layer (Y1), resulting in a double-sided adhesive tape with superior adhesion. A weight-average molecular weight (Mw) of 1,600,000 or less further improves the adhesion of the adhesive layer (Y1) to the fluororesin. A more preferred lower limit for the weight-average molecular weight (Mw) of the above (meth)acrylic copolymer is 100,000, and a more preferred upper limit is 1,200,000.

[0057] The preferred lower limit for the ratio of the weight-average molecular weight (Mw) to the number-average molecular weight (Mn) of the (meth)acrylic copolymer (molecular weight distribution (Mw / Mn)) is 1.05, and the preferred upper limit is 10.0. When the molecular weight distribution (Mw / Mn) of the (meth)acrylic copolymer is 1.05 or higher, the adhesive layer (Y1) becomes more flexible, and the workability of the resulting double-sided adhesive sheet is further improved. In addition, the resulting double-sided adhesive tape becomes more adhesive to fluororesin. When the molecular weight distribution (Mw / Mn) of the (meth)acrylic copolymer is 10.0 or lower, the proportion of low molecular weight components is suppressed, the bulk cohesive force of the adhesive layer (Y1) is improved, and the resulting adhesive tape becomes more adhesive. A more preferred upper limit for the molecular weight distribution (Mw / Mn) of the (meth)acrylic copolymer is 9.0, an even more preferred upper limit is 8.0, and an even more preferred upper limit is 7.0.

[0058] In this specification, weight-average molecular weight (Mw) and number-average molecular weight (Mn) refer to the weight-average molecular weight (Mw) and number-average molecular weight (Mn) measured in standard polystyrene equivalent as determined by gel permeation chromatography (GPC), respectively. Specifically, a (meth)acrylic copolymer is diluted 50-fold with tetrahydrofuran (THF), and the diluted solution is filtered through a filter (material: polytetrafluoroethylene, pore diameter: 0.2 μm). The obtained filtrate is supplied to a gel permeation chromatograph (Waters, "2690 Separations Module," etc.), and GPC measurement is performed under conditions of sample flow rate of 1 mL / min and column temperature of 40°C to measure the polystyrene equivalent molecular weight of the (meth)acrylic copolymer and determine the weight-average molecular weight (Mw) and number-average molecular weight (Mn). For example, a GPC KF-802.5L (Showa Denko Corporation) can be used as the column, and for example, a differential refractometer can be used as the detector. Furthermore, the molecular weight distribution (Mw / Mn) can be measured using the obtained weight-average molecular weight (Mw) and number-average molecular weight (Mn).

[0059] Methods for adjusting the weight-average molecular weight (Mw) and molecular weight distribution (Mw / Mn) of the above-mentioned (meth)acrylic copolymer to within the above range include, for example, adjusting the composition of the monomers constituting the (meth)acrylic copolymer, the polymerization method, the polymerization conditions, etc.

[0060] The preferred lower limit for the glass transition temperature (Tg) of the above (meth)acrylic copolymer is -70°C, and the preferred upper limit is -30°C. Having the glass transition temperature of the above (meth)acrylic copolymer within this range improves the workability of the resulting double-sided adhesive sheet. Furthermore, the resulting double-sided adhesive tape exhibits superior adhesion to fluororesin. A more preferred lower limit for the glass transition temperature (Tg) of the above (meth)acrylic copolymer is -60°C, and a more preferred upper limit is -40°C. In this specification, the glass transition temperature is the value obtained in the first run when measured using a differential scanning calorimeter (for example, Hitachi High-Tech Science Corporation's "SII Exstar 6000 / DSC 6220") under a nitrogen atmosphere and a heating rate of 10°C / min.

[0061] As polymerization methods for synthesizing the above-mentioned (meth)acrylic copolymer, conventionally known methods can be used in which monomers from which the above-mentioned constituent units are derived are subjected to a radical reaction in the presence of a polymerization initiator. Examples include solution polymerization (boiling point polymerization or constant temperature polymerization), emulsion polymerization, suspension polymerization, and bulk polymerization. Among these, solution polymerization is preferred because it is easy to synthesize.

[0062] When solution polymerization is used as the polymerization method described above, examples of reaction solvents include ethyl acetate, toluene, methyl ethyl ketone, methyl sulfoxide, ethanol, acetone, and diethyl ether. The above reaction solvents may be used individually or in combination of two or more types.

[0063] Examples of polymerization initiators include organic peroxides and azo compounds. Examples of the above-mentioned organic peroxides include 1,1-bis(t-hexylperoxy)-3,3,5-trimethylcyclohexane, t-hexylperoxypivalate, t-butylperoxypivalate, 2,5-dimethyl-2,5-bis(2-ethylhexanoylperoxy)hexane, t-hexylperoxy-2-ethylhexanoate, t-butylperoxy-2-ethylhexanoate, t-butylperoxyisobutyrate, t-butylperoxy-3,5,5-trimethylhexanoate, and t-butylperoxylaurate. Examples of the above-mentioned azo compounds include azobisisobutyronitrile and azobiscyclohexanecarbonitride. The polymerization initiators described above may be used alone or in combination of two or more.

[0064] The styrene-based elastomer is preferably a block copolymer having a block derived from the styrene-based monomer and a block derived from a conjugated diene monomer, possessing rubber elasticity at room temperature, and having a hard segment portion and a soft segment portion. The block derived from the styrene-based monomer is the hard segment portion, and the block derived from the conjugated diene monomer is the soft segment portion.

[0065] Examples of the styrene monomers mentioned above include styrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, α-methylstyrene, 2,4-dimethylstyrene, 2,4-diisopropylstyrene, 4-t-butylstyrene, 5-t-butyl-2-methylstyrene, vinylethylbenzene, divinylbenzene, trivinylbenzene, divinylnaphthalene, t-butoxystyrene, vinylbenzyldimethylamine, (4-vinylbenzyl)dimethylaminoethyl ether, N,N-dimethylaminoethylstyrene, N,N-dimethylaminomethylstyrene, 2-ethylstyrene, 3-ethylstyrene, 4-ethylstyrene, 2-t-butylstyrene, 3-t-butylstyrene, 4-t-butylstyrene, vinylxylene, vinylnaphthalene, vinylpyridine, diphenylethylene, and tertiary amino group-containing diphenylethylene. Among these, styrene is preferred because it is readily available industrially. Examples of the tertiary amino group-containing diphenylethylene mentioned above include 1-(4-N,N-dimethylaminophenyl)-1-phenylethylene. The above-mentioned styrene monomers may be used individually or in combination of two or more types.

[0066] Examples of the above-mentioned conjugated diene monomers include isoprene, 1,3-butadiene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 1,3-hexadiene, 1,3-heptadiene, 2-phenyl-1,3-butadiene, 3-methyl-1,3-pentadiene, and 2-chloro-1,3-butadiene. Among these, 1,3-butadiene and isoprene are preferred due to their high polymerization reactivity and ease of industrial availability. The above-mentioned conjugated diene monomers may be used individually or in combination of two or more types.

[0067] Furthermore, in order to improve retention and heat resistance by chemically imparting a crosslinked structure to the above-mentioned conjugated diene monomer, a copolymer of a polar functional group-containing monomer such as maleic anhydride may be used for the block derived from the above-mentioned conjugated diene monomer.

[0068] Examples of the styrene-based elastomers mentioned above include styrene-isoprene-styrene (SIS) block copolymer, styrene-butadiene-styrene (SBS) block copolymer, styrene-chloroprene-styrene block copolymer, styrene-ethylene-butylene-styrene copolymer (SEBS), styrene-ethylene-propylene-styrene copolymer (SEPS), and styrene-isobutylene-styrene copolymer (SIBS). Among these, SIS block copolymer and SBS block copolymer are preferred, and SIS block copolymer is more preferred, because the resulting adhesive tape tends to exhibit high adhesive strength and is less likely to peel off the adherend even when immersed in an alkaline chemical solution. The above-mentioned styrene-based elastomers may be used individually or in combination of two or more types.

[0069] The styrene-based elastomer preferably includes a triblock copolymer of a block derived from the styrene-based monomer and a block derived from the conjugated diene monomer, and more preferably includes a diblock copolymer of a block derived from the styrene-based monomer and a block derived from the conjugated diene monomer, in addition to the triblock copolymer. The preferred lower limit for the content of the diblock copolymer in the styrene-based elastomer (hereinafter sometimes referred to as the "diblock ratio") is 50% by mass. When the diblock ratio is 50% by mass or higher, the adhesive strength of the adhesive layer (Y1) to the adherend is further improved, and the resulting adhesive tape has superior adhesive properties. In addition, the flexibility of the adhesive layer (Y1) is further improved, so the adhesive strength of the adhesive layer (Y1) to the fluororesin is further improved. A more preferred lower limit for the diblock ratio is 70% by mass. Furthermore, from the viewpoint of further improving the cohesive force of the adhesive layer (Y1), the preferred upper limit of the jiblock ratio is 90% by mass. The above diblock ratio can be calculated from the peak area ratio of each copolymer measured by gel permeation chromatography (GPC).

[0070] A preferred upper limit for the content of blocks derived from the styrene monomer in the above-mentioned styrene-based elastomer (hereinafter sometimes referred to as "styrene content") is 20% by mass. When the styrene content is 20% by mass or less, the adhesive layer (Y1) does not become too hard, the adhesive strength to the adherend is further improved, and the resulting adhesive tape has superior adhesion. A more preferred upper limit for the styrene content is 16% by mass. Furthermore, from the viewpoint of further improving the cohesive force of the adhesive layer (Y1), the preferred lower limit of the styrene content is 8% by mass. The above styrene content is, 1 It can be calculated from the peak area ratio of each block measured by 1H-NMR.

[0071] The preferred lower limit for the weight-average molecular weight of the above styrene-based elastomer is 50,000, and the preferred upper limit is 600,000. A weight-average molecular weight of 50,000 or more for the above styrene-based elastomer increases the bulk strength of the adhesive layer (Y1), resulting in a more adhesive tape with superior adhesion. A weight-average molecular weight of 600,000 or less for the above styrene-based elastomer further improves the compatibility between the above styrene-based elastomer and other components. A more preferred lower limit for the weight-average molecular weight of the above styrene-based elastomer is 100,000, and a more preferred upper limit is 500,000.

[0072] Examples of commercially available ethylene-vinyl acetate copolymers include HM200 (manufactured by Cemedyne Co., Ltd.). Examples of commercially available chloroprene rubbers include 575F (manufactured by Cemedyne Co., Ltd.) and G17 (manufactured by Konishi Co., Ltd.). Examples of commercially available nitrile rubbers include 501F (manufactured by Cemedyne Co., Ltd.). Examples of commercially available polyurethane resins include SHM107-PUR (manufactured by Seedam Corporation). Examples of commercially available polyamide resins include SHM301-PAD (manufactured by Seedam Corporation). Examples of commercially available polyolefin resins include PPET1200F (manufactured by Toagosei Co., Ltd.). Examples of commercially available polyester resins include PH-413 (manufactured by Nippon Matai Co., Ltd.). Examples of commercially available epoxy resins include 1500 (manufactured by Cemedyne Co., Ltd.). Examples of commercially available silicone resins include KR-3700 (manufactured by Shin-Etsu Chemical Co., Ltd.).

[0073] The preferred lower limit for the content of the base polymer (P1) in the adhesive composition (X1) is 50% by mass, and the preferred upper limit is 99% by mass. By keeping the content of the base polymer (P1) within this range, the adhesive properties such as peel strength and holding strength of the adhesive layer (Y1) can be well-balanced. The more preferred lower limit for the content of the base polymer (P1) is 75% by mass, and the more preferred upper limit is 90% by mass.

[0074] From the viewpoint of further improving adhesive strength, the above adhesive composition (X1) preferably contains a tackifying resin (T1).

[0075] The tackifying resin (T1) preferably contains at least one tackifying resin selected from the group consisting of rosin ester resins, terpene resins, terpene phenol resins, and petroleum resins. By including at least one tackifying resin selected from the group consisting of rosin ester resins, terpene resins, terpene phenol resins, and petroleum resins in the tackifying resin (T1), the adhesive strength of the adhesive layer (Y1) can be further improved. In particular, since the adhesive strength can be further improved, it is more preferable that the tackifying resin (T1) contains at least one tackifying resin selected from the group consisting of rosin ester resins and terpene resins.

[0076] The preferred lower limit of the softening temperature of the tackifying resin (T1) is 50°C, and the preferred upper limit is 200°C. A softening temperature of 50°C or higher for the tackifying resin (T1) prevents the adhesive layer (Y1) from becoming too soft and reducing its adhesive strength. A softening temperature of 200°C or lower for the tackifying resin (T1) improves the wettability of the interface of the adhesive layer (Y1), preventing interfacial delamination. Furthermore, if the base polymer (P1) includes the (meth)acrylic copolymer, the glass transition temperature (Tg) of the (meth)acrylic copolymer is further reduced, improving the flexibility of the adhesive layer (Y1), thus improving the workability of the resulting double-sided adhesive sheet. The adhesive strength of the adhesive layer (Y1) to the fluororesin is also improved. A more preferred lower limit of the softening temperature of the tackifying resin (T1) is 70°C, and a more preferred upper limit is 150°C. Note that the softening temperature refers to the softening temperature measured according to JIS K 2207 (ring-ball method).

[0077] The preferred lower limit of the hydroxyl value of the tackifying resin (T1) is 0 mgKOH / g, and the preferred upper limit is 200 mgKOH / g. Having the hydroxyl value of the tackifying resin (T1) within this range improves the wettability of the interface of the adhesive layer (Y1), thereby suppressing interfacial delamination. A more preferred lower limit of the hydroxyl value of the tackifying resin (T1) is 30 mgKOH / g, and a more preferred upper limit is 130 mgKOH / g. The above hydroxyl value can be measured according to JIS K 1557 (phthalic anhydride method).

[0078] The rosin ester resins mentioned above are resins obtained by esterifying rosin resins mainly composed of abietic acid, disproportionated rosin resins, hydrogenated rosin resins, or dimers of resin acids such as abietic acid (polymerized rosin resins) with alcohol. Some of the hydroxyl groups of the alcohol used in esterification are not used in the esterification process and are instead contained within the resin, thereby adjusting the hydroxyl value to the range described above. Examples of such alcohols include polyhydric alcohols such as ethylene glycol, glycerin, and pentaerythritol. Examples of commercially available rosin ester resins include Pine Crystal KE-359 (manufactured by Arakawa Chemical Industries, Ltd., hydroxyl value: 40 mg KOH / g, softening temperature: 100°C).

[0079] The above-mentioned terpene resin is a resin that has structural units derived from monoterpene compounds and does not have structural units derived from aromatic compounds. Examples of commercially available terpene resins include YS Resin PX1250 (manufactured by Yasuhara Chemical Co., Ltd., hydroxyl value: 0 mg KOH / g, softening temperature: 125°C).

[0080] The above-mentioned terpene phenol resin is a resin having structural units derived from monoterpene compounds and structural units derived from phenol compounds. In this specification, the term "phenol compound" in the terpene phenol resin refers to a compound that contains an aromatic ring structure having only one phenolic hydroxyl group and does not contain an aromatic ring structure having two or more phenolic hydroxyl groups. The constituent units derived from the phenol compound in the terpene phenol resin do not include the constituent unit (A-1) and the constituent unit (A-1') in the tackifying resin (T2-1) described later. Examples of commercially available terpene phenol resins include YS Polystar G150 (manufactured by Yasuhara Chemical Co., Ltd., hydroxyl value: 120 mg KOH / g, softening temperature: 150°C).

[0081] Examples of commercially available petroleum-based resins include Alcon P-140 (manufactured by Arakawa Chemical Industries, Ltd., hydroxyl value: 0 mg KOH / g, softening temperature: 140°C).

[0082] The preferred lower limit for the content of the tackifying resin (T1) per 100 parts by mass of the base polymer (P1) is 10 parts by mass, and the preferred upper limit is 100 parts by mass. A content of 10 parts by mass or more of the tackifying resin (T1) can further improve the adhesive strength of the adhesive layer (Y1). A content of 100 parts by mass or less of the tackifying resin (T1) can prevent the adhesive layer (Y1) from becoming too hard and reducing its adhesive strength. A more preferred lower limit for the content of the tackifying resin (T1) is 20 parts by mass, and a more preferred upper limit is 80 parts by mass.

[0083] The adhesive composition (X1) preferably contains a crosslinking agent. In particular, if the base polymer (P1) contains the (meth)acrylic copolymer, the adhesive composition (X1) preferably contains a crosslinking agent. By containing a crosslinking agent in the adhesive layer (Y1), the (meth)acrylic copolymer forms a crosslinked structure through chemical crosslinking, resulting in a double-sided adhesive tape with superior adhesion. Furthermore, from the viewpoint of storage stability and other factors, the crosslinking agent may be added to the adhesive composition (X1) immediately before forming the adhesive layer (Y1).

[0084] Examples of the crosslinking agents include isocyanate-based crosslinking agents, aziridine-based crosslinking agents, epoxy-based crosslinking agents, and metal chelate-type crosslinking agents. In particular, it is preferable that the crosslinking agent includes at least one selected from the group consisting of isocyanate-based crosslinking agents and epoxy-based crosslinking agents, as this enables appropriate chemical crosslinking of the (meth)acrylic copolymer and further improves the adhesive strength of the adhesive layer (Y1).

[0085] Examples of commercially available isocyanate-based crosslinking agents include Coronate L-45 (manufactured by Tosoh Corporation), Takenate 500 (manufactured by Mitsui Chemicals), and Desmodule L-75 (manufactured by Covestro Corporation). Examples of commercially available epoxy crosslinking agents include E-5C (manufactured by Soken Chemical Co., Ltd.) and E-5XM (manufactured by Soken Chemical Co., Ltd.).

[0086] The preferred lower limit for the content of the crosslinking agent in the above adhesive composition (X1) per 100 parts by mass of the (meth)acrylic copolymer is 0.1 parts by mass, and the preferred upper limit is 10 parts by mass. Having the crosslinking agent content within this range allows for appropriate chemical crosslinking of the (meth)acrylic copolymer, further improving the adhesive strength of the adhesive layer (Y1). A more preferred lower limit for the crosslinking agent content is 0.5 parts by mass, and a more preferred upper limit is 5.0 parts by mass.

[0087] From the viewpoint of further improving adhesive strength, the above adhesive composition (X1) preferably contains a silane coupling agent. Examples of the silane coupling agents mentioned above include vinyltrimethoxysilane, vinyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, and 3-aminopropyltriethoxysilane. The silane coupling agents described above may be used individually or in combination of two or more.

[0088] The preferred lower limit for the content of the silane coupling agent per 100 parts by mass of the base polymer (P1) is 0.1 parts by mass, and the preferred upper limit is 3.0 parts by mass. A content of 0.1 parts by mass or more of the silane coupling agent can further improve the adhesive strength of the adhesive layer (Y1). A content of 3.0 parts by mass or less of the silane coupling agent can suppress bleed-out of the silane coupling agent. A more preferred lower limit for the content of the silane coupling agent is 0.5 parts by mass, and a more preferred upper limit is 2.0 parts by mass.

[0089] The above adhesive composition (X1) may optionally contain conventionally known fine particles and additives such as inorganic fine particles, conductive fine particles, antioxidants, foaming agents, organic fillers, and inorganic fillers.

[0090] The preferred lower limit for the gel fraction of the adhesive layer (Y1) is 15% by mass, and the preferred upper limit is 60% by mass. When the gel fraction of the adhesive layer (Y1) is 15% by mass or more, the bulk strength of the adhesive layer (Y1) is increased, and the resulting double-sided adhesive tape has superior adhesion. When the gel fraction of the adhesive layer (Y1) is 60% by mass or less, the flexibility of the adhesive layer (Y1) is further improved, and the adhesive strength of the adhesive layer (Y1) is further improved. The more preferred lower limit for the gel fraction of the adhesive layer (Y1) is 25% by mass, and the more preferred upper limit is 50% by mass. The gel fraction of the adhesive layer (Y1) can be measured by the following methods, etc. Specifically, a test specimen is prepared by cutting a laminate having the adhesive layer (Y1) and a substrate, or the adhesive layer (Y1) alone, into a planar rectangular shape with a width of 20 mm and a length of 40 mm. The test specimen is immersed in an organic solvent at 23°C for 24 hours, then removed from the organic solvent and dried at 110°C for 1 hour. If the base polymer (P1) is a (meth)acrylic copolymer, ethyl acetate can be used as the organic solvent; if the base polymer (P1) is a styrene-based elastomer or silicone resin, toluene can be used. The mass of the dried test specimen is measured, and the gel fraction is calculated using the following formula (3). Note that the test specimen is not laminated with a release film to protect the adhesive layer (Y1). If the test specimen does not have a substrate, W0 is calculated as 0. Gel fraction (mass %) = 100 × (W2 - W0) / (W1 - W0) (3) (W0: Mass of the substrate, W1: Mass of the test specimen before immersion, W2: Mass of the test specimen after immersion and drying)

[0091] The gel fraction of the adhesive layer (Y1) can be adjusted to within the above range by, for example, changing the type or constituent units of the base polymer (P1) (for example, changing the type of monomer constituting the (meth)acrylic copolymer), adjusting the content ratio of the base polymer (P1), adjusting the weight-average molecular weight of the base polymer (P1), adjusting the type and content of the crosslinking agent, etc.

[0092] The adhesive layer (Y1) described above has a preferred lower limit of 50 N / 25 mm for its 180° peel strength against SUS at 23°C. Since the adhesive layer (Y1) has a 180° peel strength of 50 N / 25 mm or higher for SUS at 23°C, the adhesive layer (Y1) exhibits superior adhesive strength, resulting in the adhesive sheet of the present invention having higher adhesion. A more preferred lower limit for the 180° peel strength of the adhesive layer (Y1) for SUS at 23°C is 75 N / 25 mm, and an even more preferred lower limit is 100 N / 25 mm. Furthermore, there is no particular preferred upper limit for the 180° peel force of the adhesive layer (Y1) against SUS at 23°C, but the practical upper limit is 500 N / 25 mm. The 180° peel force on the adhesive layer (Y1) at 23°C relative to SUS can be measured by the following method. Specifically, by using a 2kg rubber roller and making one back-and-forth motion at a speed of 300mm / min, an adhesive sheet with the adhesive layer (Y2) side backed with a 23μm thick PET film is cut to a size of 25mm wide x 100mm long. Then, the adhesive layer (Y1) side is placed on a SUS plate (SUS304 plate that has been washed with ethanol and then wiped dry), and a laminate is created by pressing it together under pressure of 0.1MPa for 10 minutes in an environment of 120℃. A 180° peel test is performed on the obtained laminate using a tensile testing machine (Shimadzu Corporation, "Autograph," etc.) in accordance with JIS Z 0237, under conditions of 23℃, 50%RH, and a peeling speed of 300mm / min. By peeling the double-sided adhesive tape from the SUS plate, the 180° peel force of the adhesive layer (Y1) side relative to SUS at 23℃ can be measured.

[0093] Methods for adjusting the 180° peel force of the adhesive layer (Y1) to SUS at 23°C include, for example, changing the type or constituent units of the base polymer (P1) (for example, changing the copolymerization ratio or monomer composition of the base polymer (P1)), adjusting the type or content of the tackifying resin (T1), changing the thickness of the adhesive layer (Y1), or changing the substrate.

[0094] The preferred lower limit for the thickness of the adhesive layer (Y1) is 50 μm, and the preferred upper limit is 1000 μm. By having the thickness of the adhesive layer (Y1) within this range, the adhesive layer (Y1) will have sufficient adhesive strength. A more preferred lower limit for the thickness of the adhesive layer (Y1) is 100 μm, and a more preferred upper limit is 700 μm.

[0095] The adhesive layer described above may include layers other than the adhesive layer (Y1) described above, as long as it does not impair the effects of the present invention.

[0096] Preferably, the above adhesive layer further includes an adhesive layer (Y2) formed using an adhesive composition (X2). By including the above adhesive layer (Y2), it becomes possible to select an adhesive suitable for bonding to adherends such as sheets and cans containing fluororesin, and by bonding the fluororesin via the above adhesive layer (Y2), the double-sided adhesive tape with separator of the present invention makes it possible to easily bond fluororesin to cans and the like.

[0097] The adhesive layer (Y2) is formed using the adhesive composition (X2). The above adhesive composition (X2) preferably contains a base polymer (P2). Examples of the base polymer (P2) include (meth)acrylic copolymers, styrene elastomers, and silicone resins. In particular, the base polymer (P2) preferably contains at least one selected from the group consisting of (meth)acrylic copolymers and styrene elastomers, in order to allow for a wide range of designs for the adhesive layer (Y2) and for the adhesive layer (Y2) to exhibit strong adhesive strength. Furthermore, from the viewpoint of suppressing contamination of the adherend, the base polymer (P2) is preferably a base polymer other than a silicone resin.

[0098] Examples of the (meth)acrylic copolymer, styrene elastomer, and silicone resin in the above-mentioned base polymer (P2) are the same as those in the above-mentioned base polymer (P1).

[0099] The preferred lower limit and preferred upper limit of the content of the base polymer (P2) in the adhesive composition (X2) are 30% by mass and 99.5% by mass, respectively. Having the base polymer (P2) content within this range further improves the adhesion of the adhesive layer (Y2) to the fluororesin. A more preferred lower limit for the base polymer (P2) content is 40% by mass, a more preferred upper limit is 99% by mass, an even more preferred lower limit is 50% by mass, and an even more preferred upper limit is 95% by mass.

[0100] The above adhesive composition (X2) preferably contains a tackifying resin (T2). Preferably, the tackifying resin (T2) contains a tackifying resin (T2-1) having at least one constituent unit (A) selected from the group consisting of constituent units (A-1), (A-1'), (A-2), (A-2'), (A-3), (A-3'), (A-4), and (A-4') represented by the above formula. By including the tackifying resin (T2-1) in the adhesive composition (X2), the adhesive layer (Y2) can exhibit higher adhesive strength, particularly to low-polarity adherends (e.g., fluororesins). In particular, the interaction with the adherend can be greatly improved, and the adhesive strength to the adherend can be further enhanced, so it is preferable that the above-mentioned structural unit (A) is at least one selected from the group consisting of structural unit (A-1), structural unit (A-1'), structural unit (A-2), structural unit (A-2'), structural unit (A-3), and structural unit (A-3'), and it is more preferable that it is at least one selected from the group consisting of structural unit (A-1) and structural unit (A-1'). By the above-mentioned structural unit (A) being at least one selected from the group consisting of structural unit (A-1) and structural unit (A-1'), the interaction with the adherend can be further greatly improved. Furthermore, since monomers containing bio-derived materials, which will be described later, can be easily used as monomers constituting the above-mentioned structural unit (A-1) and structural unit (A-1'), it is preferable from the viewpoint of saving petroleum resources. Furthermore, if the base polymer (P2) contains the (meth)acrylic copolymer, the tackifying resin (T2-1) has appropriate polarity, which further improves its compatibility with the (meth)acrylic copolymer.

[0101] The tackifying resin (T2-1) may have the above-mentioned structural unit (A) in the side chain, or in the main chain skeleton or at the ends of the main chain skeleton. In particular, it is preferable that the tackifying resin (T2-1) has the above-mentioned structural unit (A) in the main chain skeleton or at the ends of the main chain skeleton, as this allows it to have suitable physical properties required as a tackifying resin.

[0102] In the above constituent unit (A), R 1 ~R 7 Each of these represents a hydrogen atom, an aliphatic hydrocarbon group, an aromatic hydrocarbon group, a polar functional group, an aliphatic hydrocarbon group having a polar functional group, or an aromatic hydrocarbon group having a polar functional group. Examples of the above-mentioned aliphatic hydrocarbon group include linear, branched, or cyclic alkyl groups having 1 to 20 carbon atoms. Examples of the above-mentioned aromatic hydrocarbon groups include substituted or unsubstituted aryl groups having 6 to 20 carbon atoms. Specific examples of the polar functional group include, for example, an amino group, a carboxy group, a carbonyl group, an alkoxy group, a hydroxyl group, a nitrile group, a nitro group, and the like. R 1 As R, a polar functional group other than a hydroxyl group can be used. R 2 As R, a polar functional group other than a carboxy group can be used. R 3 As R, a polar functional group other than the group represented by OR 4 can be used. R 5 As R, a polar functional group other than the group represented by NR 6 R 7 can be used. Examples of the aliphatic hydrocarbon group having the polar functional group include, for example, a group in which one or more hydrogens in the aliphatic hydrocarbon group are substituted with the polar functional group. Examples of the aromatic hydrocarbon group having the polar functional group include, for example, a group in which one or more hydrogens in the aromatic hydrocarbon group are substituted with the polar functional group.

[0103] In the above tackifier resin (T2-1), the plurality of R 1 contained in one constitutional unit (A-1) may be the same or different from each other. Also, the plurality of R 1 contained in different constitutional units (A-1) may be the same or different from each other. Similarly, the plurality of R 1 contained in one constitutional unit (A-1') may be the same or different from each other. Also, the plurality of R 1 contained in different constitutional units (A-1') may be the same or different from each other.

[0104] Similarly, the plurality of R 2 contained in one constitutional unit (A-2) may be the same or different from each other. Also, the plurality of R 2 contained in different constitutional units (A-2) may be the same or different from each other. Similarly, the plurality of R 2These may be the same or different. Also, multiple Rs contained in different constituent units (A-2') 2 They may be the same or they may be different.

[0105] Similarly, multiple Rs contained within a single constituent unit (A-3) 3 These may be the same or different. Also, multiple Rs contained in different constituent units (A-3) 3 These may be the same or different. Similarly, multiple Rs contained within a single constituent unit (A-3') 3 These may be the same or different. Also, multiple Rs contained in different constituent units (A-3') 3 They may be the same or they may be different.

[0106] Similarly, multiple Rs contained within a single constituent unit (A-3) 4 These may be the same or different. Also, multiple Rs contained in different constituent units (A-3) 4 These may be the same or different. Similarly, multiple Rs contained within a single constituent unit (A-3') 4 These may be the same or different. Also, multiple Rs contained in different constituent units (A-3') 4 They may be the same or they may be different.

[0107] Similarly, multiple Rs contained within a single constituent unit (A-4) 5 These may be the same or different. Also, multiple Rs contained in different constituent units (A-4) 5 These may be the same or different. Similarly, multiple Rs contained within a single constituent unit (A-4') 5 These may be the same or different. Also, multiple Rs contained in different constituent units (A-4') 5 They may be the same or they may be different.

[0108] Similarly, multiple Rs contained within a single constituent unit (A-4) 6 and R 7 These may be the same or different. Also, multiple Rs contained in different constituent units (A-4) 6 and R 7 These may be the same or different. Similarly, multiple Rs contained within a single constituent unit (A-4') 6 and R 7 These may be the same or different. Also, multiple Rs contained in different constituent units (A-4') 6 and R 7 They may be the same or they may be different.

[0109] In the above-mentioned structural unit (A), n and l are integers between 2 and 4, and n' and l' are integers between 2 and 5, but from the viewpoint of ease of obtaining raw materials, it is preferable that n, l, n', and l' are 2 or 3, and it is even more preferable that n, l, n', and l' are 3, as this can further improve the adhesive strength of the adhesive layer (Y2).

[0110] In the above-mentioned structural unit (A), m and k are integers between 1 and 4, and m' and k' are integers between 1 and 5, but from the viewpoint of ease of obtaining raw materials, it is preferable that m, k, m', and k' are 1, 2, or 3, and it is more preferable that m, k, m', and k' are 1, as this can further improve the adhesive strength of the adhesive layer (Y2).

[0111] More specifically, the above-mentioned constituent units (A-1) and (A-1') include, for example, a constituent unit derived from dihydroxybenzene or its derivatives (when n and n' are 2), a constituent unit derived from trihydroxybenzene or its derivatives (when n and n' are 3), and so on. These constituent units may be used individually, or two or more may be used in combination.

[0112] Examples of the above-mentioned dihydroxybenzene or its derivatives include resorcinol, pyrocatechol, hydroquinone, dihydroxytoluene, dihydroxyxylene, dihydroxyphenylethylamine hydrochloride, dihydroxybenzoic acid, dihydroxyphenylacetic acid, dihydroxyhydrocinnamic acid, dihydroxyphenylpropionic acid, dihydroxyphenylalanine, dihydroxybenzaldehyde, dihydroxyacetophenone, diacetyldihydroxybenzene, dihydroxyphenyl-2-butanone, dihydroxyphenylmethyl acetate, benzyldihydroxyphenyl ketone, dihydroxybenzamide, dihydroxymethoxybenzene, dihydroxybenzyl alcohol, dihydroxyphenylethanol, dihydroxyphenyl glycol, dihydroxyphenylacetonitrile, and dihydroxynitrobenzene. Among these, pyrocatechol is preferred because it has low steric hindrance and readily interacts with the adherend. The above-mentioned dihydroxybenzene or its derivatives may be used alone or in combination of two or more types.

[0113] Examples of the above-mentioned trihydroxybenzene or its derivatives include pyrogallol, 1,2,4-trihydroxybenzene, phloroglucinol, trihydroxytoluene, trihydroxydiphenylmethane, 6-hydroxy-L-dopa, gallic acid, methyl gallate, butyl gallate, isobutyl gallate, isoamyl gallate, hexadecyl gallate, stearyl gallate, trihydroxyacetophenone, trihydroxyphenylethanone, trihydroxyphenylbutanone, trihydroxybenzaldehyde, trihydroxybenzamide, and trihydroxynitrobenzene. Among these, pyrogallol is preferred because it has low steric hindrance and readily interacts with the adherend. The above-mentioned trihydroxybenzene or its derivatives may be used alone or in combination of two or more types.

[0114] More specifically, the above-mentioned constituent units (A-2) and (A-2') include constituent units derived from benzoic acid, salicylic acid, dihydroxybenzoic acid, gallic acid, 2-methylbenzoic acid, 3-methylbenzoic acid, 4-methylbenzoic acid, 2-ethylbenzoic acid, 3-ethylbenzoic acid, 4-ethylbenzoic acid, 4-tert-butylbenzoic acid, 2-vinylbenzoic acid, 3-vinylbenzoic acid, 4-vinylbenzoic acid, 4,4'-stilbendicarboxylic acid, and their derivatives. Among these, the constituent unit derived from 4-vinylbenzoic acid is preferred because it has less steric hindrance and readily interacts with the adherend. These constituent units may be used individually, or two or more may be used in combination.

[0115] More specifically, the above-mentioned constituent units (A-3) and (A-3') include, for example, constituent units derived from dialkoxybenzene or its derivatives (when l and l' are 2), and constituent units derived from trialkoxybenzene or its derivatives (when l and l' are 3).

[0116] Examples of the above-mentioned dialkoxybenzene or its derivatives include 1,2-dimethoxybenzene, 1,3-dimethoxybenzene, and 1,4-dimethoxybenzene. The above-mentioned dialkoxybenzene or its derivatives may be used alone or in combination of two or more types.

[0117] Examples of trialkoxybenzene or its derivatives include 1,2,3-trimethoxybenzene, 1,2,4-trimethoxybenzene, and 1,3,5-trimethoxybenzene. Among these, 1,2,3-trimethoxybenzene is preferred because it has low steric hindrance and readily interacts with the adherend. The above-mentioned trialkoxybenzene or its derivatives may be used alone or in combination of two or more types.

[0118] More specifically, the above-mentioned constituent units (A-4) and (A-4') include, for example, constituent units derived from aminobenzene or its derivatives (when k and k' are 1). Examples of the above-mentioned aminobenzene or its derivatives include aniline, methylaniline, ethylaniline, dimethylaniline, and diethylaniline. The above-mentioned aminobenzene or its derivatives may be used alone or in combination of two or more types.

[0119] The above-mentioned component (A) may consist solely of petroleum-derived materials, but it is preferable that it includes bio-derived materials. The depletion of petroleum resources and the emission of carbon dioxide from the combustion of petroleum-derived products are serious concerns. Therefore, attempts are being made to conserve petroleum resources by using bio-derived materials instead of petroleum-derived materials. It is preferable from the standpoint of conserving petroleum resources if the above-mentioned component (A) includes bio-derived materials. Furthermore, if the above-mentioned component (A) includes bio-derived materials, since bio-derived materials are originally produced by absorbing carbon dioxide from the atmosphere, it is thought that burning them will not increase the total amount of carbon dioxide in the atmosphere, which is also preferable from the standpoint of reducing carbon dioxide emissions. Examples of monomers constituting the above-mentioned constituent unit (A), which includes bio-derived materials, include resorcinol, dihydroxyphenylethylamine hydrochloride, dihydroxyhydrocinnamic acid, dihydroxyphenylalanine, dihydroxybenzaldehyde, dihydroxybenzyl alcohol, pyrogallol, 1,2,4-trihydroxybenzene, phloroglucinol, 6-hydroxy-L-dopa, gallic acid, methyl gallate, butyl gallate, isobutyl gallate, isoamyl gallate, hexadecyl gallate, stearyl gallate, trihydroxyacetophenone, trihydroxybenzaldehyde, trihydroxybenzamide, trihydroxynitrobenzene, and the like.

[0120] The preferred lower limit of the content (on a molar basis) of the constituent unit (A) in the tackifying resin (T2-1) is 1 mol%, and the preferred upper limit is 60 mol%. By having a content of 1 mol% or more of the constituent unit (A), the adhesive strength of the adhesive layer (Y2) can be further improved by blending the tackifying resin (T2-1) into the adhesive composition (X2). By having a content of 60 mol% or less of the constituent unit (A), the tackifying resin (T2-1) will have the preferred physical properties required for a tackifying resin. A more preferred lower limit of the content of the constituent unit (A) is 5 mol%, a more preferred upper limit is 50 mol%, an even more preferred lower limit is 10 mol%, and an even more preferred upper limit is 30 mol%. Furthermore, the preferred lower limit (by mass) of the content ratio (by mass) of the constituent unit (A) in the tackifying resin (T2-1) is 0.9% by mass, and the preferred upper limit is 60% by mass. By having a content ratio of 0.9% by mass or more of the constituent unit (A), the adhesive strength of the adhesive layer (Y2) can be further improved by blending the tackifying resin (T2-1) into the adhesive composition (X2). By having a content ratio of 60% by mass or less of the constituent unit (A), the tackifying resin (T2-1) will have the preferred physical properties required as a tackifying resin. A more preferred lower limit for the content ratio of the constituent unit (A) is 5% by mass, a more preferred upper limit is 50% by mass, an even more preferred lower limit is 10% by mass, and an even more preferred upper limit is 30% by mass.

[0121] Preferably, the tackifying resin (T2-1) further has a constituent unit (B) derived from at least one monomer (b) selected from the group consisting of terpene monomers and vinyl monomers. By having the above constituent unit (B) in the tackifying resin (T2-1), the adhesive strength of the adhesive layer (Y2) can be further improved. Furthermore, from the viewpoint of improving compatibility with the base polymer, the tackifying resin (T2-1) is preferably composed of structural units derived from terpene monomers. Since the structural units derived from terpene monomers have an aliphatic hydrocarbon group having an unsaturated double bond, the tackifying resin (T2-1) having structural units derived from terpene monomers improves the compatibility between the tackifying resin (T2-1) and the base polymer (P2), and suppresses a decrease in the adhesive strength of the adhesive layer (Y2) due to deterioration of compatibility.

[0122] Examples of the above-mentioned terpene monomers include α-pinene, β-pinene, limonene, dipentene, δ-3-carene, dimethyloctatriene, allocimene, myrcene, ocimene, linalool, and cosmene. Among these, α-pinene, β-pinene, or limonene are preferred because they can further improve the adhesive strength of the adhesive layer (Y2). As the vinyl monomers mentioned above, vinyl monomers that do not have a structure containing two or more aromatic rings in one molecule (for example, naphthalene structure, anthracene structure, biphenyl structure, anthraquinone structure, benzophenone structure, etc.) are preferred from the viewpoint of improving the compatibility between the tackifying resin (T2-1) and the base polymer (P2). Examples of vinyl monomers that do not have a structure containing two or more aromatic rings in a single molecule include ethylene, propylene, butylene, hexene, vinyl acetate, vinyl chloride, styrene, α-methylstyrene, coumarone, indene, vinyltoluene, divinylbenzene, divinyltoluene, and 2-phenyl-2-butene. Among these, styrene is preferred because it can further improve the adhesive strength of the adhesive layer (Y2). The above monomer (b) may be used alone or in combination of two or more types.

[0123] The above-mentioned component unit (B) may consist solely of petroleum-derived materials, but it is preferable that it includes bio-derived materials. The depletion of petroleum resources and the emission of carbon dioxide from the combustion of petroleum-derived products are serious concerns. Therefore, attempts are being made to conserve petroleum resources by using bio-derived materials instead of petroleum-derived materials. It is preferable from the standpoint of conserving petroleum resources if the above-mentioned component unit (B) includes bio-derived materials. Furthermore, if the above-mentioned component unit (B) includes bio-derived materials, since bio-derived materials are originally produced by absorbing carbon dioxide from the atmosphere, it is thought that burning them will not increase the total amount of carbon dioxide in the atmosphere, which is also preferable from the standpoint of reducing carbon dioxide emissions. Examples of monomers (b) that constitute the above-mentioned constituent unit (B) containing bio-derived materials include terpene monomers, ethylene, propylene, hexene, and the like.

[0124] The preferred lower limit for the content of the constituent unit (B) in the tackifying resin (T2-1) is 40 mol%, and the preferred upper limit is 99 mol%. By having a content of 40 mol% or more of the constituent unit (B), the tackifying resin (T2-1) can have the desirable physical properties required for a tackifying resin. By having a content of 99 mol% or less of the constituent unit (B), the content of the constituent unit (A) can be sufficiently secured, thereby further improving the adhesive strength of the adhesive layer (Y2), and in particular, further improving the adhesive strength even to adherends with low polarity. The more preferred lower limit for the content of the constituent unit (B) is 50 mol%, and the more preferred upper limit is 90 mol%.

[0125] The tackifying resin (T2-1) described above is preferably a copolymer having a structure represented by the following formula. In particular, when the above constituent unit (A) is present in or at the end of the main chain skeleton, it is preferable that the copolymer has a structure represented by the following formula. Copolymers having such a structure are obtained by a cationic polymerization method as described later, and can further improve the adhesive strength of the adhesive layer (Y2), and in particular can further improve the adhesive strength even to low-polarity adherends.

[0126] [ka]

[0127] In the formula, A represents a constituent unit (A), B represents a constituent unit (B), and s and t each represent an integer greater than or equal to 1. * represents a connection.

[0128] The tackifying resin (T2-1) is preferably a copolymer having the above-mentioned structural unit (A) and the above-mentioned structural unit (B), and may further have other structural units. When the tackifying resin (T2-1) is a copolymer having the above-mentioned structural unit (A) and the above-mentioned structural unit (B), the above-mentioned structural unit (A) and the above-mentioned structural unit (B) may be copolymerized randomly, or they may be copolymerized in a regular or periodic manner, for example, when each forms a block segment and the block segments are bonded to each other.

[0129] The tackifying resin (T2-1) preferably has an aliphatic hydrocarbon group having an unsaturated double bond. The tackifying resin (T2-1) may have the aliphatic hydrocarbon group having an unsaturated double bond in the constituent unit (A) or the constituent unit (B), or in other constituent units. In particular, from the viewpoint of ease of synthesis and improving the compatibility between the tackifying resin (T2-1) and the base polymer (P2), and especially between the tackifying resin (T2-1) and the styrene elastomer, it is preferable that the aliphatic hydrocarbon group having an unsaturated double bond is present in the constituent unit (B) or other constituent units. The constituent unit (B) or other constituent units having such aliphatic hydrocarbon group having an unsaturated double bond are not particularly limited, but it is preferable that the constituent unit (B) is derived from at least one monomer (b) selected from the group consisting of terpene monomers and vinyl monomers. In other words, it is preferable that the tackifying resin (T2-1) has the aliphatic hydrocarbon group having an unsaturated double bond in a constituent unit (B) derived from at least one monomer (b) selected from the group consisting of terpene monomers and vinyl monomers. In particular, it is preferable that the aliphatic hydrocarbon group having an unsaturated double bond is contained in a constituent unit derived from a terpene monomer, as this can further improve the adhesive strength of the adhesive layer (Y2).

[0130] Other constituent units mentioned above include, for example, constituent units derived from other phenolic monomers not included in constituent unit (A), and constituent units derived from maleic anhydride. Other phenolic monomers mentioned above include, for example, phenol, cresol, xylenol, propylphenol, norylphenol, methoxyphenol, bromophenol, bisphenol A, bisphenol F, bisphenol S, and dihydroxynaphthalene. The other phenolic monomers mentioned above may be used individually or in combination of two or more.

[0131] The preferred lower limit of the weight-average molecular weight (Mw) of the above tackifying resin (T2-1) is 400, and the preferred upper limit is 10,000. When the weight-average molecular weight (Mw) of the above tackifying resin (T2-1) is within this range, the above tackifying resin (T2-1) possesses the desirable physical properties required for a tackifying resin. A more preferred lower limit of the weight-average molecular weight (Mw) of the above tackifying resin (T2-1) is 500, a more preferred upper limit is 5000, an even more preferred lower limit is 700, and an even more preferred upper limit is 3000. Methods for adjusting the weight-average molecular weight (Mw) to the above range include, for example, adjusting the composition, polymerization method, and polymerization conditions of the tackifying resin (T2-1).

[0132] The preferred lower limit of the Young's modulus of the tackifying resin (T2-1) at 25°C is 10 MPa. A Young's modulus of 10 MPa or higher at 25°C for the tackifying resin (T2-1) provides appropriate hardness and desirable physical properties required for a tackifying resin. A more preferred lower limit for the Young's modulus of the tackifying resin (T2-1) at 25°C is 50 MPa, and an even more preferred lower limit is 70 MPa. Furthermore, from the viewpoint of preventing the adhesive layer (Y2) from becoming too hard and reducing the adhesive strength, the preferred upper limit for the Young's modulus of the tackifying resin (T2-1) at 25°C is 10,000 MPa, and the more preferred upper limit is 5,000 MPa. The Young's modulus of the tackifying resin (T2-1) at 25°C can be measured by performing a tensile test using a tensile testing machine (such as the "Autograph" manufactured by Shimadzu Corporation) under the conditions of a tensile speed of 200 mm / min, a grip distance of 15 mm, and a temperature of 25°C. A sample for this measurement can be obtained, for example, by filling a mold measuring 10 × 50 mm with the tackifying resin (T2-1) and melting it at a temperature 100°C higher than the glass transition temperature to produce a test piece with a thickness of 1 mm.

[0133] Methods for adjusting the Young's modulus of the tackifying resin (T2-1) at 25°C to within the above range include, for example, adjusting the molecular weight or weight-average molecular weight of the tackifying resin (T2-1), the composition and content ratio of the constituent units (A) and (B) in the tackifying resin (T2-1), etc.

[0134] The preferred lower limit for the glass transition temperature of the tackifying resin (T2-1) is 0°C, and the preferred upper limit is 200°C. Because the glass transition temperature of the tackifying resin (T2-1) is within this range, the Young's modulus of the tackifying resin (T2-1) at 25°C is easily adjusted to within this range, thus the tackifying resin (T2-1) possesses the desirable physical properties required for a tackifying resin. A more preferred lower limit for the glass transition temperature of the tackifying resin (T2-1) is 10°C, and a more preferred upper limit is 150°C.

[0135] The preferred lower limit of the iodine value of the tackifying resin (T2-1) is 2.0 g / 100 g, and the preferred upper limit is 180 g / 100 g. Having an iodine value of 2.0 g / 100 g or higher makes it easier to suppress the decrease in adhesive strength of the adhesive layer (Y2) caused by poor compatibility between the tackifying resin (T2-1) and the base polymer (P2). Having an iodine value of 180 g / 100 g or lower further improves the adhesive strength of the adhesive layer (Y2), and in particular, it can further improve adhesive strength even to low-polarity substrates. A more preferred lower limit of the iodine value of the tackifying resin (T2-1) is 70 g / 100 g, and a more preferred upper limit is 170 g / 100 g. The iodine value is an indicator of the amount of unsaturated double bonds (C=C bond amount), and refers to the value measured in accordance with the method described in "JIS K 0070:1992".

[0136] The preferred lower limit for the content of bio-derived carbon (carbon atoms) in the carbon (carbon atoms) of the above-mentioned tackifying resin (T2-1) is 10%. A bio-derived carbon content of 10% or more is an indicator that a product is "bio-based". The above tackifying resin (T2-1) is preferable if it contains 10% or more bio-derived carbon, from the viewpoint of conserving petroleum resources and reducing carbon dioxide emissions. A more preferable lower limit for the bio-derived carbon content of the above tackifying resin (T2-1) is 30%, an even more preferable lower limit is 60%, an even more preferable lower limit is 70%, and a particularly preferable lower limit is 90%. There is no particular preferred upper limit for the bio-derived carbon content of the above tackifying resin (T2-1), and it may be 100%. Furthermore, while bio-derived carbon contains a certain percentage of the radioactive isotope (C-14), petroleum-derived carbon contains almost no C-14. Therefore, the percentage of bio-derived carbon in the above-mentioned tackifying resin (T2-1) can be calculated by measuring the concentration of C-14 contained in the compound. Specifically, this can be measured in accordance with ASTM D6866-22, a standard widely used in the bioplastics industry.

[0137] The tackifying resin (T2-1) described above also includes hydrogenated compounds of the compounds mentioned above. A hydrogenated compound is a compound in which at least partially the carbon-carbon double bonds present in the tackifying resin (T2-1) described above have been saturated by hydrogenation. That is, the adhesive composition (X2) may contain a hydrogenated compound in which some of the carbon-carbon double bonds in the tackifying resin (T2-1) have been hydrogenated, or it may contain a hydrogenated compound in which all of the carbon-carbon double bonds in the tackifying resin (T2-1) have been hydrogenated. Even such a hydrogenated compound can be suitably used as a tackifying resin to be blended into the adhesive composition (X2), and can improve the adhesive strength of the adhesive layer (Y2), and in particular can improve the adhesive strength even to adherends with low polarity.

[0138] The method for producing the tackifying resin (T2-1) described above is not particularly limited, but when the constituent unit (A) is present in or at the end of the main chain skeleton, the following method is preferred, for example. In other words, a method of copolymerizing monomer (a) constituting the above-mentioned structural unit (A) with at least one monomer (b) selected from the group consisting of terpene monomers and vinyl monomers constituting the above-mentioned structural unit (B) (hereinafter also referred to as "production method [I]") is preferred.

[0139] The monomer (a) is preferably at least one selected from the group consisting of monomer (a-1), monomer (a-2), monomer (a-3), and monomer (a-4), which are represented by the following formula.

[0140] [ka]

[0141] [ka]

[0142] [ka]

[0143] [ka]

[0144] In formulas (a-1) to (a-4), R 1 ~R 7 Each of the following represents a hydrogen atom, an aliphatic hydrocarbon group, an aromatic hydrocarbon group, a polar functional group, an aliphatic hydrocarbon group having a polar functional group, or an aromatic hydrocarbon group having a polar functional group. n'' represents an integer between 2 and 5, preferably 2 or 3, and more preferably 3. m'' represents an integer between 1 and 5. l'' represents an integer between 2 and 5. k'' represents an integer between 1 and 5.

[0145] In the method for producing the tackifying resin (T2-1) described above [I], it is preferable to copolymerize monomer (a) and monomer (b) by cationic polymerization. By using the cationic polymerization described above, monomer (a) and monomer (b) can be copolymerized without prior chemical modification to protect the functional groups of monomer (a), such as phenolic hydroxyl groups, carboxyl groups, alkoxy groups, and amino groups, and subsequent deprotection is also unnecessary. Therefore, monomer (a) and monomer (b) can be copolymerized in a simpler one-step reaction process, leading to a reduction in impurities and an improvement in yield.

[0146] A preferred method for copolymerizing monomer (a) and monomer (b) by cationic polymerization is to react monomer (a) and monomer (b) in the presence of a Lewis acid. This method is thought to generate cations of monomer (b), leading to cationic polymerization between monomers (b) and a Fridel-Crafts alkylation reaction between monomer (a) and monomer (b). Repeated reactions of this nature allow for the production of a copolymer having constituent units (A) derived from monomer (a) and constituent units (B) derived from monomer (b). The Lewis acid mentioned above is not particularly limited, and conventionally known Lewis acids can be used, such as aluminum chloride (AlCl3), diethylaluminum chloride (Et2AlCl2), tin(IV) chloride (SnCl4), titanium(IV) chloride (TiCl4), boron trichloride (BCl3), and boron trifluoride ether complex (BF3·EtO). Among these, aluminum chloride (AlCl3) is preferred because it yields a higher yield of copolymer.

[0147] More specifically, for example, if pyrogallol is used as monomer (a) and α-pinene is used as monomer (b), and these are reacted in the presence of aluminum chloride (AlCl3), which is a Lewis acid, the reaction shown in the following scheme is expected to proceed. Specifically, a cation of monomer (b), α-pinene, is generated, and cationic polymerization of α-pinenes proceeds (upper part of the scheme below), while a Fridel-Crafts alkylation reaction proceeds between monomer (a), pyrogallol, and monomer (b), α-pinene (middle part of the scheme below). By repeatedly performing such reactions, a copolymer having structural units derived from pyrogallol and structural units derived from α-pinene can be obtained (lower part of the scheme below). Such a copolymer will have structural units derived from pyrogallol in the main chain skeleton or at the ends of the main chain skeleton.

[0148] [ka]

[0149] In the expression, s and t each represent an integer greater than or equal to 1. * represents a concatenation.

[0150] As for the method of producing the above-mentioned tackifying resin (T2-1), if the above-mentioned structural unit (A) is present in the side chain, for example, the following method is preferred. In other words, a method of copolymerizing a monomer (a') obtained by introducing an unsaturated double bond to monomer (a) constituting the above-mentioned structural unit (A), with at least one monomer (b) selected from the group consisting of terpene monomers and vinyl monomers constituting the above-mentioned structural unit (B) (hereinafter also referred to as "production method [II]") is preferred.

[0151] Examples of the above monomer (a') include 2-vinylbenzoic acid, 3-vinylbenzoic acid, 4-vinylbenzoic acid, and 4,4'-stilbendicarboxylic acid. Among these, 4-vinylbenzoic acid is preferred because it has less steric hindrance and readily interacts with the adherend. The above monomer (a') may be used alone or in combination of two or more types.

[0152] In the above method for producing the tackifying resin (T2-1) [II], it is preferable to copolymerize the monomer (a') and the monomer (b) by cationic polymerization, similar to the method for producing the tackifying resin (T2-1) [I]. A preferred method for copolymerizing monomer (a') and monomer (b) by cationic polymerization is to react monomer (a') and monomer (b) in the presence of a Lewis acid as described above. By such a method, cationic polymerization proceeds between the unsaturated double bond in monomer (a') and the unsaturated double bond in monomer (b), and a copolymer having constituent units (A) derived from monomer (a') and constituent units (B) derived from monomer (b) can be obtained.

[0153] The above-mentioned tackifying resin (T2-1) can improve the adhesive strength of the adhesive layer (Y2) even in a small amount compared to conventional tackifying resins. The preferred lower limit of the content of the above-mentioned tackifying resin (T2-1) per 100 parts by mass of the above-mentioned base polymer (P1) is 5 parts by mass, and the preferred upper limit is 30 parts by mass. By having a content of 5 parts by mass or more of the above-mentioned tackifying resin (T2-1), the adhesive strength of the adhesive layer (Y2) can be further improved, and in particular, the adhesive strength to low-polarity adherends (e.g., fluororesins, etc.) can be further improved. By having a content of 30 parts by mass or less of the above-mentioned tackifying resin (T2-1), a decrease in adhesive strength caused by the adhesive layer (Y2) becoming too hard can be suppressed. The more preferred lower limit of the content of the above-mentioned tackifying resin (T2-1) is 10 parts by mass, and the more preferred upper limit is 20 parts by mass.

[0154] The tackifying resin preferably includes at least one tackifying resin (T2-2) selected from the group consisting of rosin ester resins, terpene resins, terpene phenol resins, and petroleum resins. By including the tackifying resin (T2-2), the adhesive strength of the adhesive layer (Y2) can be further improved. In particular, the tackifying resin (T2-2) is more preferably made up of at least one tackifying resin selected from the group consisting of rosin ester resins and terpene resins because it can further improve the adhesive strength to low-polarity adherends (e.g., fluororesins, etc.), and the tackifying resin (T2-2) is even more preferably made up of a rosin ester resin because it can further improve the adhesive strength to low-polarity adherends (e.g., fluororesins, etc.). Examples of the above-mentioned rosin ester resin, terpene resin, terpene phenol resin, and petroleum resin include those similar to those used in the tackifying resin (T1) described above.

[0155] The preferred lower limit for the content of the tackifying resin (T2-2) per 100 parts by mass of the base polymer (P2) is 10 parts by mass, and the preferred upper limit is 100 parts by mass. A content of 10 parts by mass or more of the tackifying resin (T2-2) can further improve the adhesive strength of the adhesive layer (Y2). A content of 100 parts by mass or less of the tackifying resin (T2-2) can prevent the adhesive layer (Y2) from becoming too hard and reducing its adhesive strength. A more preferred lower limit for the content of the tackifying resin (T2-2) is 15 parts by mass, a more preferred upper limit is 60 parts by mass, an even more preferred upper limit is 50 parts by mass, and an even more preferred upper limit is 40 parts by mass.

[0156] The adhesive composition (X2) preferably contains a crosslinking agent. In particular, if the base polymer (P2) contains the (meth)acrylic copolymer, the adhesive composition (X2) preferably contains a crosslinking agent. By containing the crosslinking agent in the adhesive composition (X2), the (meth)acrylic copolymer can form a crosslinked structure by chemical crosslinking, thereby improving the bulk cohesive force of the adhesive layer (Y2) and increasing the gel fraction of the adhesive layer (Y2), as described later, thus improving the adhesive strength of the resulting adhesive tape. Furthermore, from the viewpoint of storage stability and other factors, the crosslinking agent may be added to the adhesive composition (X2) immediately before forming the adhesive layer (Y2).

[0157] Examples of the crosslinking agents include isocyanate-based crosslinking agents, aziridine-based crosslinking agents, epoxy-based crosslinking agents, and metal chelate-type crosslinking agents. In particular, it is preferable that the crosslinking agent includes at least one selected from the group consisting of isocyanate-based crosslinking agents and epoxy-based crosslinking agents, as this enables appropriate chemical crosslinking of the (meth)acrylic copolymer and further improves the adhesive strength of the adhesive layer (Y2). Examples of the above-mentioned isocyanate-based crosslinking agent and epoxy-based crosslinking agent include those the same as those used in the above-mentioned adhesive composition (X1).

[0158] The preferred lower limit for the content of the crosslinking agent in the above adhesive composition (X2) per 100 parts by mass of the (meth)acrylic copolymer is 0.01 parts by mass, and the preferred upper limit is 20 parts by mass. Having the crosslinking agent content within this range allows for appropriate chemical crosslinking of the (meth)acrylic copolymer, further improving the adhesive strength of the adhesive layer (Y2). A more preferred lower limit for the crosslinking agent content is 0.1 parts by mass, a more preferred upper limit is 10 parts by mass, an even more preferred lower limit is 0.5 parts by mass, and an even more preferred upper limit is 8.0 parts by mass.

[0159] The above adhesive composition (X2) may further contain a coloring agent for the purpose of providing light-shielding properties. Examples of the coloring agent include carbon black, aniline black, and titanium dioxide. Among these, carbon black is preferred because it is relatively inexpensive and chemically stable.

[0160] The above adhesive composition (X2) may optionally contain conventionally known fine particles and additives such as inorganic fine particles, conductive fine particles, antioxidants, foaming agents, organic fillers, and inorganic fillers.

[0161] The preferred lower limit for the gel fraction of the adhesive layer (Y2) is 15% by mass, and the preferred upper limit is 60% by mass. When the gel fraction of the adhesive layer (Y2) is 15% by mass or more, the bulk strength of the adhesive layer (Y2) is increased, and the resulting adhesive tape has superior adhesion. When the gel fraction of the adhesive layer (Y2) is 60% by mass or less, the flexibility of the adhesive layer (Y2) is further improved, and the adhesion strength of the adhesive layer (Y2) to the fluororesin is further improved. The more preferred lower limit for the gel fraction of the adhesive layer (Y2) is 25% by mass, and the more preferred upper limit is 50% by mass. The gel fraction of the adhesive layer (Y2) can be measured using the same method as described above for the gel fraction of the adhesive layer (Y1).

[0162] The gel fraction of the adhesive layer (Y2) can be adjusted to within the above range by, for example, changing the type or constituent units of the base polymer (P2) (for example, changing the type of monomer constituting the (meth)acrylic copolymer), adjusting the content ratio of the base polymer (P1), adjusting the weight-average molecular weight of the base polymer (P2), adjusting the type and content of the crosslinking agent, etc.

[0163] The adhesive layer (Y2) described above has a preferred lower limit of 5.0 N / 25 mm for its 180° peel strength against PTFE at 23°C. The adhesive tape of the present invention exhibits excellent adhesion to fluororesins due to the adhesive layer (Y2) having a 180° peel strength of 5.0 N / 25 mm or higher for PTFE at 23°C. A more preferred lower limit for the adhesive layer (Y2)'s 180° peel strength against PTFE at 23°C is 7.0 N / 25 mm, and an even more preferred lower limit is 10 N / 25 mm. Furthermore, there is no particular preferred upper limit for the 180° peel force of the adhesive layer (Y2) against PTFE at 23°C, but the practical upper limit is 100 N / 25 mm.

[0164] The 180° peel force of the above adhesive layer (Y2) against PTFE at 23°C can be measured by the following method. Specifically, an adhesive tape backed with the adhesive layer (Y1) using a 50 μm thick PET film is cut to a size of 25 mm wide x 100 mm long. Then, the adhesive layer (Y2) side is placed on a 2 mm thick polytetrafluoroethylene board (for example, "Yodoflon" manufactured by Yodogawa Hutech Co., Ltd.), and pressed together by one back-and-forth motion using a 2 kg rubber roller at a speed of 300 mm / min. After that, the laminate A is produced by curing it for 24 hours in an environment of 23°C and 50% RH. A 180° peel test is performed on the obtained laminate A using a tensile testing machine ("Autograph" manufactured by Shimadzu Corporation, etc.) in accordance with JIS Z 0237, under conditions of 23°C, 50% RH, and a peeling speed of 300 mm / min. By peeling the adhesive tape from the polytetrafluoroethylene board, the 180° peel force of the adhesive layer (Y2) against PTFE at 23°C can be measured.

[0165] Methods for adjusting the 180° peel force of the adhesive layer (Y2) to PTFE at 23°C to within the range described above include, for example, changing the type or constituent units of the base polymer (P2) described later (for example, changing the copolymerization ratio or monomer composition of the base polymer (P2)), adjusting the type or content of the tackifying resin (T2) described later, changing the thickness of the adhesive layer (Y2), or changing the substrate.

[0166] The preferred lower limit for the thickness of the adhesive layer (Y2) is 50 μm, and the preferred upper limit is 1000 μm. The adhesive layer (Y2) having a thickness within this range ensures sufficient adhesive strength. A more preferred lower limit for the thickness of the adhesive layer (Y2) is 100 μm, a more preferred upper limit is 500 μm, and an even more preferred upper limit is 300 μm.

[0167] The above-mentioned double-sided adhesive tape may have layers other than the adhesive layer, as long as it does not impair the effects of the present invention.

[0168] The above-mentioned double-sided adhesive tape preferably has a base material. Having a base material in the double-sided adhesive tape results in an adhesive tape with superior bonding workability.

[0169] From the viewpoint of heat resistance and chemical resistance, the above-mentioned substrate preferably contains at least one selected from the group consisting of polyester resin, polyimide resin, polyether resin, polyolefin resin, polyurethane resin, metal, glass fiber, and carbon fiber.

[0170] Examples of the polyester resins mentioned above include polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT), polyethylene furanoate (PEF), polylactic acid (PLA), and polybutylene succinate (PBS). Examples of the polyimide resins mentioned above include Kapton (manufactured by DuPont) and Upirex (manufactured by UBE). Examples of the polyether resins mentioned above include polyetheretherketone (PEEK) and polyetherimide (PEI). Examples of the polyolefin resins mentioned above include polyethylene (PE), polypropylene (PP), and ethylene-vinyl acetate copolymer (EVA). The polyurethane resin described above is a resin composition comprising a polyisocyanate and a polyol. Examples of the polyisocyanate include 4,4'-diphenylmethane diisocyanate (MDI), and examples of the polyol include polypropylene glycol (PPG). Examples of the above-mentioned metals include stainless steel (SUS), copper, and aluminum. Examples of the glass fibers mentioned above include glass cloth. Examples of the carbon fibers mentioned above include carbon cloth.

[0171] Furthermore, the generation of air at the adhesive surface when the above-mentioned substrate is pressed against the adhesive layer can cause the adhesive layer to peel off easily. Therefore, it is preferable that the above-mentioned substrate includes at least one shape selected from the group consisting of nonwoven fabrics and woven fabrics, as this improves the anchoring strength of the substrate and improves air release properties by providing air passages to suppress air generation, thereby suppressing the peeling of the adhesive layer.

[0172] Examples of commercially available nonwoven fabric-like base materials include G2260-1S (manufactured by Toray International, Inc.). Examples of the woven base material mentioned above include glass cloth and carbon cloth. Examples of commercially available glass cloths among those mentioned above include KS2770 (manufactured by Nitto Boseki Co., Ltd.) and L73A×1045 (manufactured by Arisawa Seisakusho Co., Ltd.). Among the carbon cloths mentioned above, commercially available examples include C-540 (manufactured by Hagiwara Industries Co., Ltd.).

[0173] The preferred lower limit for the thickness of the above-mentioned substrate is 50 μm, and the preferred upper limit is 1000 μm. Having the substrate thickness within this range further improves the interlayer strength of the double-sided adhesive tape. A more preferred lower limit for the thickness of the above-mentioned substrate is 100 μm, and a more preferred upper limit is 500 μm.

[0174] The above double-sided adhesive tape has a minimum thickness of 250 μm. A thickness of 250 μm or more allows the double-sided adhesive tape to achieve a high level of both adhesive strength and ease of application. A preferred minimum thickness for the above double-sided adhesive tape is 300 μm, and a more preferred minimum thickness is 400 μm. Furthermore, from the viewpoint of preventing the load due to the weight of the double-sided adhesive tape from becoming too large, the preferred upper limit for the thickness of the double-sided adhesive tape is 1200 μm, and the more preferred upper limit is 1000 μm.

[0175] When the above double-sided adhesive tape includes a base material, the preferred upper limit of the ratio of the thickness of the base material to the thickness of the double-sided adhesive tape is 35%. A ratio of 35% or less for the base material results in superior adhesive reliability for the double-sided adhesive tape. A more preferred upper limit for the ratio of the base material thickness is 30%, and an even more preferred upper limit is 25%. Furthermore, from the viewpoint of increasing the overall strength of the tape by the base material, the preferred lower limit for the ratio of the base material thickness is 1%, and the more preferred lower limit is 3%.

[0176] Furthermore, the method for manufacturing the double-sided adhesive tape with separator according to the present invention 1 is not particularly limited, and examples include the following methods. First, an adhesive solution (a) containing an adhesive composition (X1) is prepared by adding a base polymer (P1), a tackifying resin (T1), and, if necessary, a crosslinking agent or solvent. The obtained adhesive solution (a) is applied to the release layer of a separator such as a release PET film, and the solvent in the solution is dried and removed to create a laminated film in which an adhesive layer (Y1) is formed on the separator. Next, the prepared laminated film is superimposed on a substrate so that the adhesive layer (Y1) and the substrate face each other, thereby obtaining a laminate of the substrate and a substrate having an adhesive layer (Y1) on one side of the substrate. Note that the step of applying the adhesive solution (a) to the separator may be completed in one step, or it may be performed multiple times by applying it on top of the applied adhesive solution. By adjusting the number of application steps, the thickness of the adhesive layer (Y1) can be easily adjusted. Furthermore, an adhesive solution (b) containing an adhesive composition (X2) is prepared by adding a base polymer (P2), a tackifying resin (T2), and, if necessary, a crosslinking agent or solvent. The obtained adhesive solution (b) is applied to any separator, and the solvent in the solution is completely dried and removed to form an adhesive layer (Y2). The step of applying the adhesive solution (b) to the separator may be performed once, or it may be performed multiple times by applying it on top of the applied adhesive solution. By adjusting the number of application steps, the thickness of the adhesive layer (Y2) can be easily adjusted. Then, by overlapping the substrate of the laminate containing the adhesive layer (Y1) with the adhesive layer (Y2) so that they face each other, peeling off the separator that protects the adhesive layer (Y2), and curing for 48 hours in an environment of 40°C and 50%RH, a double-sided adhesive tape with a separator according to the present invention 1 can be manufactured, which has an adhesive layer (Y1), an adhesive layer (Y2), and a substrate, and a separator that protects the adhesive layer (Y1) of the double-sided adhesive tape.

[0177] Furthermore, the method for manufacturing the double-sided adhesive tape with separator according to the present invention 2 is not particularly limited, and examples include the following methods. First, an adhesive solution (a) containing an adhesive composition (X1) is prepared by adding a base polymer (P1), a tackifying resin (T1), and, if necessary, a crosslinking agent or solvent. The obtained adhesive solution (a) is applied to the release layer of a separator such as a release PET film, and the solvent in the solution is dried and removed to create a laminated film in which an adhesive layer (Y1) is formed on the separator. Next, the prepared laminated film is placed on a substrate so that the adhesive layer (Y1) and the substrate face each other, and cured for 48 hours in an environment of 40°C and 50%RH to obtain a laminate having the substrate and the adhesive layer (Y1) on one side of the substrate. Note that the step of applying the adhesive solution (a) to the separator may be completed in one step, or it may be performed multiple times by applying it on top of the applied adhesive solution. By adjusting the number of application steps, the thickness of the adhesive layer (Y1) can be easily adjusted. Furthermore, an adhesive solution (b) containing an adhesive composition (X2) is prepared by adding a base polymer (P2), a tackifying resin (T2), and, if necessary, a crosslinking agent or solvent. The obtained adhesive solution (b) is applied to the release layer of a separator such as a release PET film, and the solvent in the solution is dried and removed to create a laminated film in which an adhesive layer (Y2) is formed on the separator. Note that the step of applying the adhesive solution (b) to the separator may be performed once, or it may be performed multiple times by applying it on top of the applied adhesive solution. By adjusting the number of application steps, the thickness of the adhesive layer (Y2) can be easily adjusted. By overlapping a base material and a laminate having an adhesive layer (Y1) on one side of the base material, with the side of the base material without the adhesive layer (Y1) facing the adhesive layer (Y2) of a laminated film having an adhesive layer (Y2) formed on a separator, and curing for 48 hours in an environment of 40°C and 50%RH, a double-sided adhesive tape having an adhesive layer (Y1), an adhesive layer (Y2), and a base material, and a separator-equipped double-sided adhesive tape of the present invention 2 having separators on both sides of the double-sided adhesive tape, can be manufactured.

[0178] The double-sided adhesive tape with separator of the present invention has a minimum thickness of 350 μm. Having a thickness of 350 μm or more improves the peelability of the separator, making it easier to peel off the double-sided adhesive tape. A preferred minimum thickness for the double-sided adhesive tape with separator of the present invention is 375 μm, and a more preferred minimum thickness is 400 μm. Furthermore, from the viewpoint of preventing the load on the double-sided adhesive tape with separator of the present invention from becoming too large due to its own weight, the preferred upper limit for the thickness of the double-sided adhesive tape with separator of the present invention is 1400 μm, and the more preferred upper limit is 1300 μm.

[0179] The applications of the separator-equipped double-sided adhesive tape of the present invention are not particularly limited, but because the separator-equipped double-sided adhesive tape of the present invention can suppress the peeling of the separator from the other adhesive layer when one adhesive layer of the double-sided adhesive tape is bonded to the fluororesin, it can be suitably used to easily bond fluororesin to a can or the like. For this reason, it is suitably used to bond fluororesin to dissimilar members for various purposes. More specifically, various purposes include, for example, promoting sliding of friction surfaces, preventing friction of sliding parts, insulating coating, and protecting the adherend from high temperatures or chemical solutions. Among these, it is suitably used to protect the adherend, and is particularly suitably used to protect the adherend from chemical solutions. Furthermore, because the separator-equipped double-sided adhesive tape of the present invention has excellent adhesive reliability when bonding fluororesin to a can or the like, it is suitably used for lining (surface treatment covering the inner surface of the can) of a chemical solution tank, and is suitably used for lining a chemical solution tank for semiconductors or for the chemical industry. The double-sided adhesive tape with separator of the present invention offers excellent adhesive reliability when bonding fluororesin to a can body or the like, allowing for problem-free application of lining to the can body.

[0180] In the case where the double-sided adhesive tape with separator of the present invention has the adhesive layer (Y2) of the double-sided adhesive tape with separator of the present invention, a method for manufacturing a chemical tank for the semiconductor or chemical industry is also one of the present invention, which includes a lining sheet manufacturing step of pressing a sheet containing fluororesin onto the adhesive layer (Y2) of the double-sided adhesive tape with separator of the present invention; a separator peeling step of peeling off the separator on the adhesive layer (Y1) side of the lining sheet manufactured in the lining sheet manufacturing step to expose the adhesive layer (Y1); and a lining sheet lamination step of laminating the adhesive layer (Y1) to the inside of the tank body of the chemical tank. The present invention provides a method for manufacturing a chemical tank that suppresses the peeling of the separator of the double-sided adhesive tape with a separator when pressing a sheet containing fluororesin, and allows for easy bonding of the fluororesin to the tank body, resulting in superior work efficiency.

[0181] Examples of sheets containing the fluororesin used in the lining sheet manufacturing process include sheets containing polytetrafluoroethylene (PTFE), sheets containing perfluoroalkoxyalkane (PFA), sheets containing perfluoroethylenepropene copolymer (FEP), sheets containing ethylenetetrafluoroethylene copolymer (ETFE), sheets containing polyvinylidene fluoride (PVDF), sheets containing polyvinyl fluoride (PVF), sheets containing polychlorotrifluoroethylene (PCTFE), and sheets containing ethylenechlorotrifluoroethylene copolymer (ECTFE). Among these, sheets containing PTFE are preferred because they offer excellent heat resistance and chemical resistance. The sheet containing the above-mentioned fluororesin may be a single layer or a multi-layered sheet of two or more layers.

[0182] The sheet containing the above-mentioned fluororesin preferably has an easy-adhesion treatment layer on its surface. By having an easy-adhesion treatment layer on its surface, the lining sheet produced in the lining sheet manufacturing process exhibits excellent adhesion between the adhesive layer (Y2) and the sheet containing the fluororesin, enabling the fluororesin to be firmly bonded to the tank body of the chemical tank.

[0183] From the viewpoint of further improving the adhesion between the adhesive layer (Y2) and the sheet containing the fluororesin, the easy-adhesion treatment in the easy-adhesion treatment layer preferably includes at least one treatment selected from the group consisting of plasma irradiation, electron beam irradiation, chemical etching, and easy-adhesion layer bonding treatment.

[0184] Examples of the above-mentioned chemical etching treatments include sodium etching.

[0185] Examples of the above-mentioned easy-adhesion layer bonding treatment include an easy-adhesion layer bonding treatment using a sheet containing fluororesin, and specific examples of the easy-adhesion layer bonding treatment using a sheet containing fluororesin include glass backing treatment and carbon cloth backing treatment. Glass backing and carbon cloth backing can be performed, for example, by laminating another sheet containing fluororesin and glass cloth or carbon cloth in that order onto one surface of a sheet containing fluororesin, and then pressing them in a high-temperature environment. In the easy-adhesion layer bonding treatment using the above-mentioned fluororesin-containing sheet, the fluororesin-containing sheet can be any sheet containing the fluororesin described above, but it is preferable to use a sheet containing a thermoplastic fluororesin.

[0186] The thickness of the resin sheet containing the above-mentioned fluororesin has a preferred lower limit of 1.0 mm and a preferred upper limit of 4.0 mm. A thickness of 1.0 mm or more of the resin sheet containing the above-mentioned fluororesin improves chemical resistance. A thickness of 4.0 mm or less of the resin sheet containing the above-mentioned fluororesin improves ease of installation. A more preferred lower limit of 1.5 mm and a more preferred upper limit of 3.5 mm is the thickness of the resin sheet containing the above-mentioned fluororesin.

[0187] The surface density of the resin sheet containing the above-mentioned fluororesin is preferably at a lower limit of 1 kg / m². 2 Therefore, the preferred upper limit is 10 kg / m 2 The surface density of the resin sheet containing the above-mentioned fluororesin is 1 kg / m². 2 As a result, chemical resistance is further improved. The surface density of the resin sheet containing the above fluororesin is 10 kg / m². 2 The ease of installation is improved by the following: A more preferable lower limit for the surface density of the resin sheet containing the above-mentioned fluororesin is 2 kg / m². 2 A more preferable upper limit is 8 kg / m 2 That is the case.

[0188] A chemical tank in which the double-sided adhesive tape with separator of the present invention is attached to the inner surface of a can is also one of the present inventions. The chemical tank of the present invention allows for a strong bond of fluororesin to the inner surface of the tank body via the attached double-sided adhesive tape, thereby further suppressing peeling and lifting of the fluororesin caused by the chemical solution stored in the chemical tank to which the fluororesin is bonded. [Effects of the Invention]

[0189] According to the present invention, when bonding fluororesins, it is possible to suppress cohesive failure (weeping) of the adhesive layer accompanying the separation of the separator, so that the fluororesin and the can body or the like can be easily bonded, and a double-sided adhesive tape with a separator excellent in adhesive reliability when the fluororesin and the can body or the like are bonded can be provided. Further, according to the present invention, a method for manufacturing a chemical solution tank using the double-sided adhesive tape with a separator can be provided. Furthermore, according to the present invention, a chemical solution tank to which the double-sided adhesive tape in the double-sided adhesive tape with a separator is attached can be provided.

Brief Description of the Drawings

[0190] [Figure 1] It is a cross-sectional view schematically showing a laminate of a double-sided adhesive tape with a separator produced in an example.

Modes for Carrying Out the Invention

[0191] Hereinafter, embodiments will be given to explain the aspects of the present invention in more detail, but the present invention is not limited only to these embodiments.

[0192] (Preparation of Release Agent Solution) (Release Agent Solution 1) To 100 parts by mass of a silicone composition (manufactured by Toray Dow Corning Co., Ltd., "LTC759"), 1 part by mass of a curing catalyst (manufactured by Toray Dow Corning Co., Ltd., "SRX212") and 900 parts by mass of toluene as a solvent were added and sufficiently stirred to prepare Release Agent Solution 1.

[0193] (Release Agent Solutions 2 to 5) Release Agent Solutions 2 to 5 were prepared in the same manner as Release Agent Solution 1, except that the composition was made as shown in Table 1.

[0194]

Table 1

[0195] (Production of Separator) (Separator G) On the surface of a 75-μm-thick PET film (manufactured by Toyobo Co., Ltd., "S10") prepared as a separator base material, a release agent solution 3 was applied so that the dried thickness would be 0.5 μm, and then dried at 130°C for 1 minute to form a release layer. Next, on the back surface of the PET film having a release layer formed on its surface, a release agent solution 1 was applied so that the dried thickness would be 0.5 μm, and then dried at 130°C for 1 minute, whereby a separator G having release layers with a thickness of 0.5 μm on both surfaces of the PET film was produced.

[0196] (Separator H - I) Except that the type of the separator base material and the type of the release agent solution were made as shown in Table 2, H - I having release layers on both surfaces of the separator base material were produced in the same manner as separator G.

[0197] (Separator K - M, O) The type of the separator base material and the type of the release agent solution were made as shown in Table 2, and except that a release layer was formed only on the surface of the separator base material, separators K - M, O having a release layer on one surface (the surface) of the separator base material were produced in the same manner as separator G.

[0198] (Separator J) 900 parts by mass of methanol was added to 100 parts by mass of polyvinyl alcohol (manufactured by Sekisui Chemical Co., Ltd., "BL - 1") and stirred well to prepare a coating solution for forming a blocking layer. On the surface of a high-quality paper with a thickness of 85 μm and a basis weight of 64 g / m 2 (manufactured by Nippon Paper Industries Co., Ltd., "P - 1") prepared as a separator base material, the above coating solution for forming a blocking layer was applied so that the dried thickness would be 2 μm, and then dried at 130°C for 1 minute to form a blocking layer. On the blocking layer surface of the high-quality paper having a blocking layer formed on its surface, a release agent solution 5 was applied so that the dried thickness would be 0.5 μm, and then dried at 130°C for 1 minute to form a release layer. Next, a blocking layer was similarly formed on the back surface of the high-quality paper having a release layer formed on its surface, and then a release agent solution 4 was applied so that the dried thickness would be 0.5 μm, and then dried at 130°C for 1 minute, whereby a separator J having release layers with a thickness of 0.5 μm on both surfaces of the high-quality paper was produced.

[0199] (Separator N) Separator N was prepared in the same manner as Separator J, except that the type of release agent solution was as shown in Table 2, and the release layer was formed only on the surface of the separator substrate. Separator N had a release layer on one side (surface) of the high-quality paper.

[0200] Regarding the front and back surfaces of the fabricated separator, the side with the "release layer (front)" as shown in Table 2 shall be considered the front surface of the separator, and the side with the "release layer (back)" shall be considered the back surface of the separator.

[0201] [Table 2]

[0202] (Preparation of tackifying resin (T2-1)) (Synthesis Example 1) Fifty parts by mass of toluene were added to a reactor equipped with a thermometer, stirrer, and condenser, and after purging with nitrogen, the reactor was heated and reflux was started. After 30 minutes, while maintaining the toluene at 75°C, two parts by mass of aluminum chloride (AlCl3) were added. A solution of 50 parts by mass of catechol (pyrocatechol) (n=2) and α-pinene (molar ratio: α-pinene / catechol = 80 / 20) dissolved in 50 parts by mass of toluene was gradually added dropwise over 1 hour and 30 minutes to allow the reaction to proceed. After polymerization for 4 hours, the hydrochloric acid generated from aluminum chloride (AlCl3) was neutralized by cooling while adding 0.1 parts by mass of pyridine to the reactor. The precipitate formed by neutralization was filtered, and after liquid-liquid extraction of the obtained filtrate, the toluene was evaporated to obtain a solid tackifying resin (T2-1). Regarding the obtained tackifying resin (T2-1) 1 ¹H-NMR measurements were performed to confirm that the tackifying resin (T2-1) is a copolymer having constituent units (A) derived from catechol (pyrocatechol) and constituent units (B) derived from α-pinene (a copolymer having constituent unit (A) in or at the ends of the main chain skeleton). The obtained tackifying resin (T2-1) was dissolved in tetrahydrofuran, and the resulting solution was filtered through a filter (material: polytetrafluoroethylene, pore diameter: 0.2 μm). The obtained filtrate was supplied to a gel permeation chromatograph (Waters, 2690 Separations Module), and GPC measurements were performed under conditions of sample flow rate of 1 mL / min and column temperature of 40°C. The polystyrene-equivalent molecular weight of the tackifying resin (T2-1) was measured, and the weight-average molecular weight (Mw) was determined to be 950. A GPC KF-802.5L column (Showa Denko) was used, and a differential refractometer was used as the detector.

[0203] (Synthesis Example 2) Except for changing the constituent monomer units to 50 parts by mass of pyrogallol (n=3) and α-pinene (molar ratio: α-pinene / pyrogallol = 80 / 20), the tackifying resin (T2-1) was synthesized in the same manner as in "(Synthesis Example 1)" above, and measurements were performed. The weight-average molecular weight was 1100.

[0204] (Preparation of adhesive) (Adhesive A) To 100 parts by mass of solids of an acrylic adhesive containing a (meth)acrylic copolymer as a base polymer (manufactured by Soken Chemical Co., Ltd., "SK Dyne 1604N"), 20.0 parts by mass of a rosin ester resin (manufactured by Arakawa Chemical Industries, Ltd., "Pine Crystal KE-359") was added as a tackifying resin. Furthermore, 30 parts by mass of ethyl acetate (manufactured by Fuji Chemical Co., Ltd.) and 2.5 parts by mass of an isocyanate crosslinking agent (manufactured by Covestro, Inc., "Desmodule L-75") were added to prepare the adhesive composition, and by thoroughly stirring, adhesive A was obtained.

[0205] (Gel fraction of the adhesive layer) First, the obtained adhesive A was applied to the release surface of a 75 μm thick release PET film, and then dried at 100°C for 5 minutes to produce an adhesive tape for gel fraction measurement with a 50 μm thick adhesive layer. Next, the adhesive tape for measuring the gel fraction obtained was cut into a size of 20 mm in width and 40 mm in length. After the cut test piece was immersed in ethyl acetate at 23°C for 24 hours, it was taken out from the organic solvent and dried at 110°C for 1 hour. Then, the mass of the dried test piece was measured, and the gel fraction was calculated using the following formula (3). Note that the test piece is not laminated with a release PET film for protecting the adhesive layer. Also, W0 in formula (3) was calculated as 0. The results are shown in Table 3. Gel fraction (mass%) = 100×(W2 - W0) / (W1 - W0) (3) (W0: mass of the base material, W1: mass of the test piece before immersion, W2: mass of the test piece after immersion and drying)

[0206] (Preparation of the adhesive) (Adhesives B to E) Adhesives B to E were prepared in the same manner as adhesive A, except that the composition was made as shown in Table 3, and the gel fraction of the adhesive layer was measured. The results are shown in Table 3.

[0207] (Adhesive F) Adhesive F was prepared in the same manner as adhesive A, except that the composition was made as shown in Table 3 and 30 parts by mass of toluene was used instead of 30 parts by mass of ethyl acetate. Also, the gel fraction of the adhesive layer was measured in the same manner as adhesive A, except that the organic solvent for immersion was changed from ethyl acetate to toluene. The results are shown in Table 3.

[0208]

Table 3

[0209] (Example 1) (1) Preparation of a double-sided adhesive tape with a separator The obtained adhesive A was applied to the surface of the prepared separator G, dried at 100°C for 5 minutes, and then dried at 130°C for 10 minutes to form an adhesive layer (Y1) with a thickness of 200 μm on the surface of the separator G, thereby creating a laminated film. A PET film with a thickness of 50 μm (Toyobo Co., Ltd., "E5200") was prepared as the substrate, and the prepared laminated film was placed on top of the substrate so that the adhesive layer (Y1) faced the substrate, and then cured by heating at 40°C for 48 hours. As a result, a laminate was obtained having the substrate and the adhesive layer (Y1) and separator on one side of the substrate. Furthermore, the obtained adhesive A was applied to the surface of the release layer of the prepared separator M using a comma coater, dried at 100°C for 5 minutes, and then dried at 130°C for 10 minutes to form an adhesive layer (Y2) with a thickness of 200 μm on the surface of the separator M. Next, the adhesive layer (Y2) was superimposed on the surface of the laminate having the substrate, thereby obtaining a laminated tape having separator G, adhesive layer (Y1), substrate, adhesive layer (Y2), and separator M in this order. Then, two of the above-mentioned laminated tapes were prepared, and the separator M adjacent to the adhesive layer (Y2) of one of the laminated tapes was peeled off to form a double-sided adhesive tape and a double-sided adhesive tape with a separator (hereinafter referred to as the first laminated tape), which has a separator on one side of the double-sided adhesive tape. Then, the adhesive layer (Y2) of the double-sided adhesive tape with a separator was superimposed on the back surface of the separator G of the other laminated tape (the second laminated tape) (the side not adjacent to the adhesive layer (Y1) of the second laminated tape). By curing for 48 hours in an environment of 40°C and 50%RH, a double-sided adhesive tape with a separator (i.e., a double-sided adhesive tape with a separator having a separator on one side of the double-sided adhesive tape) having a separator, an adhesive layer (Y1), a substrate, and an adhesive layer (Y2) was laminated, and a laminate of double-sided adhesive tape with a separator was obtained in which the outermost adhesive layer (adhesive layer (Y2) in the second laminated tape) was protected by the outermost separator. The fabricated laminate of double-sided adhesive tape with a separator is shown in Figure 1. When the laminate of the separator-equipped double-sided adhesive tape is used for the measurements and evaluations described later, the first laminated tape in the obtained separator-equipped double-sided adhesive tape laminate is used as the measurement and evaluation target, the adhesive layer that is bonded to the SUS plate and the end plate is designated as adhesive layer (Y1), and the adhesive layer that is bonded to the PTFE plate is designated as adhesive layer (Y2). Furthermore, the "Configuration of double-sided adhesive tape with separator" shown in Table 4 shall represent the configuration of the first laminated tape.

[0210] (2) Measurement of 180° peeling force F1 In the above-described "(1) Preparation of double-sided adhesive tape with separator," the outermost separator adjacent to the adhesive layer (Y2) of the second laminated tape of the prepared double-sided adhesive tape with separator was peeled off to expose the adhesive layer (Y2). The exposed adhesive layer (Y2) was backed with a 23 μm thick PET film (Futamura Chemical Co., Ltd., "FE2002"), and then cut to a size of 50 mm wide and 100 mm long to prepare test specimens. Next, the prepared test specimens were tested in accordance with JIS Z 0237 using a tensile testing machine (Shimadzu Corporation, "Autograph"), by peeling the separator from the double-sided adhesive tape at 180° under conditions of 23°C and a peeling speed of 300 mm / min to measure the 180° peel force F1. The results are shown in Table 4.

[0211] (3) Measurement of 180° peeling force F2 In the above-described "(1) Preparation of double-sided adhesive tape with separator," the separator adjacent to the adhesive layer (Y1) of the first laminated tape of the prepared double-sided adhesive tape with separator was peeled off to expose the adhesive layer (Y1). The exposed adhesive layer (Y1) was backed with a 23 μm thick PET film (Futamura Chemical Co., Ltd., "FE2002"), and then cut to a size of 50 mm wide and 100 mm long to prepare test specimens. Next, the prepared test specimens were tested using a tensile testing machine (Shimadzu Corporation, "Autograph," etc.) in accordance with JIS Z 0237, under conditions of 23°C and a peeling speed of 300 mm / min, by peeling the adhesive layer (Y2) of the first laminated tape from the separator of the second laminated tape at a 180° angle to measure the 180° peel force F2. The results are shown in Table 4.

[0212] (4) Measurement of the 180° peel force of the adhesive layer (Y1) against SUS at 23°C In the above-described "(1) Preparation of double-sided adhesive tape with separator," the first laminated tape was removed from the laminated double-sided adhesive tape with separator that had been prepared. The adhesive layer (Y2) side of the obtained first laminated tape was backed with a 23 μm thick PET film (Futamura Chemical Co., Ltd., "FE2002"), and then cut to a size of 25 mm wide x 100 mm long to prepare a test piece. Next, the adhesive layer (Y1) side was placed on a 2 mm thick SUS304 plate that had been washed with ethanol and then wiped dry, and a laminate was prepared by pressurizing it at 0.1 MPa for 1 hour in an environment of 120°C. The obtained laminates were subjected to a 180° peel test in accordance with JIS Z 0237, using a Shimadzu Corporation "Autograph" instrument, under conditions of 23°C, 50% RH, and a peeling speed of 300 mm / min. The 180° peel force of the heated adhesive layer (Y1) relative to SUS at 23°C was measured by peeling the adhesive tape from the SUS plate. The results are shown in Table 4.

[0213] (5) Measurement of the 180° peel force of the adhesive layer (Y2) against PTFE at 23°C In the above-described "(1) Preparation of double-sided adhesive tape with separator," the first laminated tape was removed from the laminated double-sided adhesive tape with separator that had been prepared. The adhesive layer (Y1) side of the obtained first laminated tape was backed with a 23 μm thick PET film (Futamura Chemical Co., Ltd., "FE2002"), and then cut to a size of 25 mm wide x 100 mm long to prepare a test piece. Next, the adhesive layer (Y2) side was placed on a 2 mm thick polytetrafluoroethylene board (Yodogawa Hutech Co., Ltd., "Yodoflon"), and after one back-and-forth motion using a 2 kg rubber roller at a speed of 300 mm / min, the laminate was prepared by curing for 20 minutes in an environment of 23°C and 50% RH. The obtained laminates were subjected to a 180° peel test using a Shimadzu Autograph (manufactured by Shimadzu Corporation) in accordance with JIS Z 0237, under conditions of 23°C and a peeling speed of 300 mm / min. The 180° peel force of the adhesive layer (Y2) against PTFE at 23°C was measured by peeling the adhesive layer (Y2) from the polytetrafluoroethylene board. The results are shown in Table 4.

[0214] (Examples 2-18, Comparative Examples 1-2) In the above-described "(1) Preparation of double-sided adhesive tape with separator," a double-sided adhesive tape with separator was prepared and measured in the same manner as in Example 1, except that the type of separator, the composition of the adhesive composition (X1), the thickness of the adhesive layer (Y1), the type and thickness of the substrate, the composition of the adhesive composition (X2), and the thickness of the adhesive layer (Y2) were as shown in Tables 4 to 6. The results are shown in Tables 4 to 6.

[0215] (Example 19) (1) Preparation of double-sided adhesive tape with separator The obtained adhesive A was applied to the release layer of the prepared separator M, dried at 100°C for 5 minutes, and then dried at 130°C for 10 minutes to form an adhesive layer (Y1) with a thickness of 200 μm on the separator M, thereby creating a laminated film. A PET film with a thickness of 50 μm (Toyobo Co., Ltd., "E5200") was prepared as the substrate, and the prepared laminated film was placed on top of the substrate so that the adhesive layer (Y1) faced the substrate, and then cured by heating at 40°C for 48 hours. This resulted in obtaining a laminate having a substrate and an adhesive layer (Y1) on one side of the substrate. Furthermore, the obtained adhesive A was applied to the release layer of the prepared separator O, dried at 100°C for 5 minutes, and then dried at 130°C for 10 minutes to form an adhesive layer (Y2) with a thickness of 200 μm on the separator O, thereby producing a laminated film. A double-sided adhesive tape with a separator was obtained by overlapping a substrate with a laminate in which an adhesive layer (Y1) is formed on one side of the substrate, with the side of the substrate without the adhesive layer (Y1) facing the adhesive layer (Y2) of a laminated film in which an adhesive layer (Y2) is formed on a separator O, and curing it for 48 hours in an environment of 40°C and 50%RH. In the evaluation described later, the adhesive layer bonded to SUS was referred to as adhesive layer (Y1), and the adhesive layer bonded to PTFE was referred to as adhesive layer (Y2).

[0216] (2) Measurement of 180° peeling force F3 The adhesive layer (Y2) of the obtained double-sided adhesive tape with separator was backed with a 23 μm thick PET film (Futamura Chemical Co., Ltd., "FE2002"), and then cut to a size of 50 mm wide and 100 mm long to prepare test specimens. Next, the 180° peel force F3 of the prepared test specimens was measured using a tensile testing machine (Shimadzu Corporation, "Autograph") in accordance with JIS Z0237, by peeling the separator from the double-sided adhesive tape at 23°C and a peeling speed of 300 mm / min. The results are shown in Table 7.

[0217] (3) Measurement of 180° peeling force F4 The adhesive layer (Y1) of the obtained double-sided adhesive tape with separator was backed with a 23 μm thick PET film (Futamura Chemical Co., Ltd., "FE2002"), and then cut to a size of 50 mm wide and 100 mm long to prepare test specimens. Next, the 180° peel force F4 of the prepared test specimens was measured using a tensile testing machine (Shimadzu Corporation, "Autograph") in accordance with JIS Z0237, by peeling the second separator from the double-sided adhesive tape at 180° under conditions of 23°C and a peeling speed of 300 mm / min. The results are shown in Table 7.

[0218] (4) Measurement of the 180° peel force of the adhesive layer (Y1) against SUS at 23°C The adhesive layer (Y2) side of the obtained double-sided adhesive tape was backed with a 23 μm thick PET film (Futamura Chemical Co., Ltd., "FE2002"), and then cut to a size of 25 mm wide x 100 mm long to prepare test pieces. Next, the adhesive layer (Y1) side was placed on a 2 mm thick SUS304 plate that had been washed with ethanol and then wiped dry, and a laminate was fabricated by pressurizing it at 0.1 MPa for 1 hour in an environment of 120°C. The obtained laminates were subjected to a 180° peel test in accordance with JIS Z 0237, using a Shimadzu Corporation "Autograph" instrument, under conditions of 23°C, 50% RH, and a peeling speed of 300 mm / min. The 180° peel force of the heated adhesive layer (Y1) relative to SUS at 23°C was measured by peeling the adhesive tape from the SUS plate. The results are shown in Table 7.

[0219] (5) Measurement of the 180° peel force of the adhesive layer (Y2) against PTFE at 23°C The adhesive layer (Y1) side of the obtained double-sided adhesive tape was backed with a 23 μm thick PET film (Futamura Chemical Co., Ltd., "FE2002"), and then cut to a size of 25 mm wide x 100 mm long to prepare test specimens. Next, the adhesive layer (Y2) side was placed on a 2 mm thick polytetrafluoroethylene board (Yodogawa Hutech Co., Ltd., "Yodoflon"), and after one back-and-forth motion using a 2 kg rubber roller at a speed of 300 mm / min, the laminate was left to cure for 20 minutes in an environment of 23°C and 50% RH. The obtained laminate was subjected to a 180° peel test on the obtained laminate using a tensile testing machine (Shimadzu Corporation, "Autograph") in accordance with JIS Z 0237, under conditions of 23°C and a peeling speed of 300 mm / min, and the 180° peel force of the adhesive layer (Y2) against PTFE at 23°C was measured by peeling the adhesive layer (Y2) from the polytetrafluoroethylene board. The results are shown in Table 7.

[0220] (Examples 20-36, Comparative Examples 3-4) In the above-described "(1) Preparation of double-sided adhesive tape with separator," a double-sided adhesive tape with separator was prepared and measured in the same manner as in Example 1, except that the type of separator, the composition of the adhesive composition (X1), the thickness of the adhesive layer (Y1), the type and thickness of the substrate, the composition of the adhesive composition (X2), and the thickness of the adhesive layer (Y2) were as shown in Tables 7 to 9. The results are shown in Tables 7 to 9.

[0221] <Rating> The obtained double-sided adhesive tapes with separators were evaluated using the following method. The results are shown in Tables 4-9.

[0222] (Separator peeling off) (Examples 1-18, Comparative Examples 1-2) In the above-mentioned "(1) Preparation of double-sided adhesive tape with separator," the laminate of the prepared double-sided adhesive tape with separator was cut to a size of 50 mm in width and 100 mm in length to prepare test pieces. Next, with the first laminated tape on top of the prepared test piece, the adhesive layer (Y2) of the first laminated tape was peeled off from the separator of the second laminated tape using tweezers, and placed on a 2 mm thick polytetrafluoroethylene board (Yodogawa Hutech Co., Ltd., "Yodoflon"), and after one back-and-forth motion at a speed of 300 mm / min using a 2 kg rubber roller, it was left to stand for 20 minutes in an environment of 23°C and 50% RH to cure and prepare the laminate. Then, the presence or absence of peeling of the separator protecting the adhesive layer (Y1) when the adhesive layer (Y2) of the first laminated tape was peeled off from the separator of the second laminated tape was observed using tweezers. Evaluation was performed according to the following criteria. ◎: No peeling occurred of the separator protecting the adhesive layer (Y1). ○: Peeling of the separator protecting the adhesive layer (Y1) occurred only at the edges. △: Although peeling of the separator protecting the adhesive layer (Y1) occurred, cohesive failure (separation) of the adhesive layer did not occur along with the peeling of the separator. ×: The separator protecting the adhesive layer (Y1) peeled off, resulting in cohesive failure (separation) of the adhesive layer.

[0223] (Examples 19-36, Comparative Examples 3-4) The obtained double-sided adhesive tape with separator was cut to a size of 50 mm wide x 100 mm long. Next, the separator on the adhesive layer (Y2) side was peeled off using tweezers and placed on a 2 mm thick polytetrafluoroethylene board (Yodogawa Hutech Co., Ltd., "Yodoflon"), and after one back-and-forth motion at a speed of 300 mm / min using a 2 kg rubber roller, a laminate was created by curing for 20 minutes in an environment of 23°C and 50% RH. Then, the presence or absence of peeling of the separator protecting the adhesive layer (Y1) when the separator on the adhesive layer (Y2) side was peeled off using the tweezers was observed. Evaluation was performed according to the following criteria. The evaluation was conducted according to the following criteria. ◎: No peeling occurred of the separator protecting the adhesive layer (Y1). ○: Peeling of the separator protecting the adhesive layer (Y1) occurred only at the edges. △: Although peeling of the separator protecting the adhesive layer (Y1) occurred, cohesive failure (separation) of the adhesive layer did not occur along with the peeling of the separator. ×: The separator protecting the adhesive layer (Y1) peeled off, and along with the peeling of the separator, cohesive failure (separation) of the adhesive layer occurred.

[0224] (Adhesion reliability) The obtained double-sided adhesive tape with separator was cut to a size of 210 mm in width and 297 mm in length. After peeling off the separator protecting the adhesive layer (Y2) as needed, the adhesive layer (Y2) side was placed on a polytetrafluoroethylene plate (Yodogawa Hutech Co., Ltd., "Yodoflon") measuring 210 mm in width, 297 mm in length, and 2 mm in thickness. A laminate was created by rolling it back and forth once at a speed of 300 mm / min using a 2 kg rubber roller. The separator protecting the adhesive layer (Y1) of the above laminate was peeled off, and after heating at 100°C for 3 minutes, the adhesive layer (Y1) was immediately bonded along the circumferential direction of the inner side of a head plate (Ohama Press Co., Ltd., "10% flat head plate"). After bonding, the adhesion between the double-sided adhesive tape and the polytetrafluoroethylene plate and head plate, as well as the lifting of the above laminate from the head plate, were visually observed. Evaluation was performed according to the following criteria. ○: No floating occurred in any of the layers. △: Some lifting occurred between the adhesive layer (Y2) and the polytetrafluoroethylene plate, or between the adhesive layer (Y1) and the end plate. ×: Delamination occurred between the adhesive layer (Y2) and the polytetrafluoroethylene plate, or between the adhesive layer (Y1) and the end plate.

[0225] [Table 4]

[0226] [Table 5]

[0227] [Table 6]

[0228] [Table 7]

[0229] [Table 8]

[0230] [Table 9] [Industrial applicability]

[0231] According to the present invention, it is possible to suppress the cohesive breakdown (separation) of the adhesive layer due to the peeling of the separator when bonding fluororesins, and to provide a double-sided adhesive tape with a separator that allows easy bonding of fluororesins to cans and the like, and provides excellent adhesive reliability when bonding fluororesins to cans and the like. Furthermore, according to the present invention, it is possible to provide a method for manufacturing a chemical tank using the double-sided adhesive tape with a separator. Moreover, according to the present invention, it is possible to provide a chemical tank to which the double-sided adhesive tape with a separator has been attached. [Explanation of symbols]

[0232] 11. Double-sided adhesive tape with separator (first laminated tape) 12. Double-sided adhesive tape with separator (second layered tape) 2. Laminate of double-sided adhesive tape with separators 3 Separators 4. First adhesive layer 5 Base material 6. Second adhesive layer 7. Outermost separator

Claims

1. A double-sided adhesive tape having an adhesive layer, and a double-sided adhesive tape with a separator having a separator on one side of the double-sided adhesive tape, The adhesive layer includes an adhesive layer (Y1) formed using an adhesive composition (X1), The total thickness of the adhesive layer of the double-sided adhesive tape is 300 μm or more and 1500 μm or less. The side of the double-sided adhesive tape having a separator is referred to as surface (a), and the side of the double-sided adhesive tape not having a separator is referred to as surface (b). F is the 180° peeling force at 23°C at the interface between surface (a) and the separator. １ year, When the aforementioned surface (b) is attached to the surface of the separator that is not in contact with the surface (a) of the double-sided adhesive tape, the 180° peel force at 23°C at the interface between the aforementioned surface (b) and the separator is F ２ In that case, The following equation (1) is satisfied: A double-sided adhesive tape with a separator, characterized by the following features. F １ / F ２ ≧2.0 (1)

2. Said F １ The double-sided adhesive tape with separator according to claim 1, wherein the N / 50mm is 150mN or more and 2000mN or less.

3. Said F ２ The double-sided adhesive tape with separator according to claim 1 or 2, wherein the N / 50 mm is 1000 mN or less.

4. The double-sided adhesive tape with separator according to claim 1 or 2, wherein the separator is composed of at least one selected from the group consisting of polyester resin, polyolefin resin, and paper.

5. The double-sided adhesive tape with separator according to claim 1 or 2, wherein the separator has a release layer containing at least one release agent selected from the group consisting of polyolefin-based release agents, silicone-based release agents, and fluororesin-based release agents.

6. A double-sided adhesive tape having an adhesive layer, and a double-sided adhesive tape with a separator having separators on both sides of the double-sided adhesive tape, The adhesive layer includes an adhesive layer (Y1) formed using an adhesive composition (X1), The total thickness of the adhesive layer of the double-sided adhesive tape is 300 μm or more and 1500 μm or less. The separators on both sides of the double-sided adhesive tape with separators have different 180° peel forces at 23°C from the double-sided adhesive tape. The separator with a larger 180° peel force is designated as the first separator, and the separator with a smaller 180° peel force is designated as the second separator. The 180° peel force at 23°C between the first separator and the double-sided adhesive tape is F. ３ The 180° peel force between the second separator and the double-sided adhesive tape at 23°C is F. ４ In that case, The following equation (2) is satisfied: A double-sided adhesive tape with a separator, characterized by the following features. F ３ / F ４ ≧2.0 (2)

7. Said F ３ The double-sided adhesive tape with separator according to claim 6, wherein the N / 50 mm is 150 mN or more and 2000 mN or less.

8. Said F ４ The double-sided adhesive tape with separator according to claim 6 or 7, wherein the N / 50 mm is 1000 mN or less.

9. The double-sided adhesive tape with separators according to claim 6 or 7, wherein the first separator and the second separator are each independently composed of at least one selected from the group consisting of polyester resin, polyolefin resin, and paper.

10. The double-sided adhesive tape with separators according to claim 6 or 7, wherein the first separator and the second separator each independently have a release layer containing at least one release agent selected from the group consisting of polyolefin-based release agents, silicone-based release agents, and fluororesin-based release agents.

11. The adhesive composition (X1) contains a base polymer, The base polymer includes at least one selected from the group consisting of (meth)acrylic copolymers and styrene-based elastomers. Double-sided adhesive tape with separator according to claim 1, 2, 6, or 7.

12. The adhesive composition (X1) further contains a tackifying resin (T1), as described in claim 1, 2, 6, or 7, for the double-sided adhesive tape with separator.

13. The adhesive layer (Y1) has a 180° peel force of 50 N / 25 mm or more against SUS at 23°C, as described in claim 1, 2, 6, or 7, for a double-sided adhesive tape with a separator.

14. The double-sided adhesive tape with separator according to claim 1, 2, 6, or 7, wherein the adhesive layer further comprises an adhesive layer (Y2) formed using an adhesive composition (X2).

15. The adhesive composition (X2) contains a base polymer, The base polymer includes at least one selected from the group consisting of (meth)acrylic copolymers and styrene-based elastomers. Double-sided adhesive tape with separator according to claim 14.

16. The double-sided adhesive tape with separator according to claim 14, wherein the adhesive composition (X2) further contains a tackifying resin (T2).

17. The double-sided adhesive tape with separator according to claim 16, wherein the tackifying resin (T2) comprises a tackifying resin (T2-1) having at least one constituent unit (A) selected from the group consisting of constituent units (A-1), (A-1'), (A-2), (A-2'), (A-3), (A-3'), (A-4), and (A-4') represented by the following formula. 【Chemistry 1】 【Chemistry 2】 【Transformation 3】 【Chemistry 4】 In the formula, R １ ~R ７ * represents a hydrogen atom, an aliphatic hydrocarbon group, an aromatic hydrocarbon group, a polar functional group, an aliphatic hydrocarbon group having a polar functional group, or an aromatic hydrocarbon group having a polar functional group, respectively. n and l each represent an integer between 2 and 4, and n' and l' each represent an integer between 2 and 5. m and k each represent an integer between 1 and 4, and m' and k' each represent an integer between 1 and 5. * represents a linking part.

18. The double-sided adhesive tape with separator according to claim 14, wherein the adhesive layer (Y2) has a 180° peel strength of 5.0 N / 25 mm or more against polytetrafluoroethylene (PTFE) at 23°C.

19. The above double-sided adhesive tape further has a base material, The substrate contains at least one selected from the group consisting of polyester resin, polyimide resin, polyether resin, polyolefin resin, polyurethane resin, metal, glass fiber, and carbon fiber. Double-sided adhesive tape with separator according to claim 1, 2, 6, or 7.

20. The double-sided adhesive tape with separator according to claim 19, wherein the ratio of the thickness of the base material to the thickness of the double-sided adhesive tape is 35% or less.

21. A double-sided adhesive tape with a separator according to claim 1, 2, 6, or 7, used for lining a tank body in a chemical solution tank.

22. A lining sheet manufacturing step comprising pressing a sheet containing fluororesin onto the adhesive layer (Y2) of the double-sided adhesive tape with separator described in claim 14, A separator peeling step is performed to peel off the separator on the adhesive layer (Y1) side of the lining sheet produced in the lining sheet manufacturing step, thereby exposing the adhesive layer (Y1). This includes a lining sheet bonding step, in which the adhesive layer (Y1) is bonded to the inside of the can body of the chemical tank. A method for manufacturing a chemical tank.

23. A chemical tank having a double-sided adhesive tape with a separator according to claim 1, 2, 6, or 7 attached to the inner surface of a can.

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