WO2020116497A1

WO2020116497A1 - Method for removing pressure-sensitive adhesive tape, pressure-sensitive adhesive tape, and electronic component

Info

Publication number: WO2020116497A1
Application number: PCT/JP2019/047375
Authority: WO
Inventors: 春小谷野; 嘉謨郭; 諒小宮山; 泰志石堂
Original assignee: 積水化学工業株式会社
Priority date: 2018-12-04
Filing date: 2019-12-04
Publication date: 2020-06-11
Also published as: TW202033697A

Abstract

The purpose of the present invention is to provide: a method for removing a pressure-sensitive adhesive tape, the method making it possible that a component fixed with the pressure-sensitive adhesive tape is less apt to be damaged when recovered; a pressure-sensitive adhesive tape to be subjected to the removal method; and an electronic component including the pressure-sensitive adhesive tape to be subjected to the removal method. The method is for removing a pressure-sensitive adhesive tape which comprises a pressure-sensitive adhesive layer including a styrene-based elastomer and has been bonded to an adherend to form a multilayer structure, and comprises bringing a remover liquid having an SP value of 22.0 or less into contact with the pressure-sensitive adhesive layer of the multilayer structure and thereafter removing the pressure-sensitive adhesive tape from the adherend.

Description

Adhesive tape peeling method, adhesive tape and electronic component

TECHNICAL FIELD The present invention relates to a method for peeling an adhesive tape that is less likely to be damaged when the component fixed by the adhesive tape is collected, an adhesive tape used for the peeling method, and an electronic component using the adhesive tape used for the peeling method.

In a mobile electronic device (for example, a mobile phone, a mobile information terminal, etc.) equipped with an image display device or an input device, a double-sided adhesive tape is used for assembly. Specifically, for example, a cover panel for protecting the surface of the mobile electronic device is bonded to the touch panel module or the display panel module, the touch panel module and the display panel module are bonded, or the sensor or the battery pack is fixed. A double-sided pressure-sensitive adhesive tape is used for this purpose (for example, Patent Documents 1 and 2). The double-sided adhesive tape is also used for fixing vehicle parts (for example, a vehicle-mounted panel) to the vehicle body.

JP, 2009-242541, A JP, 2009-258274, A

Since electronic devices in recent years have become thinner and higher in density, parts such as a battery pack are fixed to a substrate or a case with an adhesive tape. When replacing a battery pack of an electronic device or taking out a reusable part from a discarded electronic device, the adhesive tape is peeled off to separate the device and the part. However, since the pressure-sensitive adhesive tape used for fixing such components has a high adhesive force, there is a problem that the components may be damaged when peeled. Particularly, in recent years, electronic device parts have become thinner and smaller, so that the above-mentioned problems are likely to occur.

In view of the above-mentioned present situation, the present invention uses a method of peeling an adhesive tape in which a component is less likely to be damaged when collecting a component fixed by the adhesive tape, an adhesive tape used in the peeling method, and an adhesive tape used in the peeling method. The purpose is to provide electronic components.

In the present invention, after the peeling liquid having an SP value of 22.0 or less is brought into contact with the pressure-sensitive adhesive layer of a laminate in which a pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer containing a styrene-based elastomer and an adherend are bonded A method for peeling an adhesive tape, comprising peeling the adherend and the adhesive tape.
The present invention is described in detail below.

The method for peeling off an adhesive tape of the present invention is, in the pressure-sensitive adhesive layer of a laminate in which an adhesive tape having a pressure-sensitive adhesive layer and an adherend are bonded together, after contacting a peeling liquid, the adherend and the adherend. Peel off the adhesive tape.
By bringing the release liquid into contact with the adhesive layer of the adhesive tape, the release liquid permeates between the adherend and the adhesive layer, reducing the adhesive strength of the adhesive tape and suppressing damage to the adherend. The adherend can be peeled off from the adhesive tape. The specific method for peeling off the adhesive tape is not particularly limited. For example, in a laminate in which a substrate and an adherend are fixed by the adhesive tape, the release liquid is poured into the gap between the adherend and the substrate, and the pressure-sensitive adhesive layer and the release liquid are brought into contact with each other, and thereafter, Examples include a method of inserting a pick or the like into a gap and lifting. The time for contacting the stripper is not particularly limited, and the time for which the stripper sufficiently penetrates can be appropriately selected according to the state of the adherend, but considering the influence of the stripper on the adherend, It is preferably 3 seconds or more and 60 seconds or less.

The pressure-sensitive adhesive layer contains a styrene elastomer.
By using a styrene-based elastomer for the pressure-sensitive adhesive layer, the adherend can be fixed with sufficient adhesive force. Further, by bringing the pressure-sensitive adhesive layer into contact with the peeling liquid, the pressure-sensitive adhesive force can be reduced, and the pressure-sensitive adhesive tape can be peeled off while suppressing damage to the adherend.

The styrene elastomer is not particularly limited, and examples thereof include styrene ethylene propylene styrene block copolymer (SEPS), hydrogenated styrene butadiene rubber (HSBR), styrene ethylene butylene styrene block copolymer (SEBS), styrene ethylene propylene block. Copolymer (SEP), Styrene Ethylene Butylene Block Copolymer (SEB), Styrene Isoprene Block Copolymer (SI), Styrene Isoprene Styrene Block Copolymer (SIS), Styrene Butadiene Block Copolymer (SB), Styrene Examples thereof include butadiene styrene block copolymer (SBS).

Among them, the styrene-based elastomer is preferably a hydrogenated styrene-based elastomer because it is easy to adjust the viscoelasticity to an appropriate degree in the design of the polymer primary structure. Examples of the hydrogenated styrene elastomer include styrene ethylene propylene styrene block copolymer (SEPS), hydrogenated styrene butadiene rubber (HSBR), and styrene ethylene butylene styrene block copolymer (SEBS).

The styrene-based elastomer preferably has a hydrogenation rate of 95% or more, and more preferably 96% or more, from the viewpoint of further suppressing contamination of the adherend. When the hydrogenation rate of the styrene-based elastomer is at least the above lower limit, it is possible to further suppress the contamination of the adherend. The hydrogenation rate of the styrene elastomer is usually 100% or less.

The styrene elastomer preferably has a structure in which a spherical phase and other phases are phase-separated.
Styrene-based elastomer is composed of a rubber segment that exhibits rubber elasticity and a styrene segment.Since the rubber segment and the styrene segment have low compatibility, the rubber segment and the styrene segment have a spherical phase and other phases in the molecule. A non-uniform phase-separated structure that exists as a separated structure may be formed. When the styrene elastomer has a phase-separated structure, the rubber segment interacts with a material having a low SP value, and the styrene segment interacts with a material having a high SP value. The adhesive force of the agent layer can be improved. Usually, there is a trade-off relationship between the adhesive force and the peeling property, and therefore, when a large amount of tacky fire or the like is used to improve the adhesive force, the peeling performance also deteriorates. However, the effect of improving the adhesive force by the phase separation hardly affects the releasability when the above-mentioned release liquid is brought into contact, so that both high adhesive force and releasability can be achieved. From the viewpoint of achieving both high adhesive strength and releasability, the preferred lower limit of the diameter of the spherical phase is 5 nm, and the more preferred lower limit thereof is 6 nm. The upper limit of the diameter of the spherical phase is not particularly limited, but is about 100 nm from the viewpoint of the stability of the spherical structure.

The styrene elastomer preferably has a styrene content of 5% by weight or more and 40% by weight or less.
When the content of styrene contained in the styrene-based elastomer is within the above range, it is possible to form a phase-separated structure of a sufficient amount of styrene segment, which makes it more difficult to peel the pressure-sensitive adhesive layer from the base material layer. it can. In addition, when the styrene content is within the above range, sufficient adhesive force can be exhibited. Further, when the styrene content is within the above range, the shape of the phase separation structure can be easily made spherical, and the adhesive force and the releasability when brought into contact with the release liquid can be further enhanced. From the viewpoint of further promoting the formation of the phase-separated structure of the styrene segment, further improving the adhesive strength and releasability, and further suppressing the peeling of the pressure-sensitive adhesive layer from the base material layer, the styrene content of the styrene elastomer is more A preferred lower limit is 7% by weight, and a more preferred upper limit is 35% by weight.

The pressure-sensitive adhesive layer preferably contains tacky fire.
By blending tacky fire in the adhesive layer, the adhesive strength of the adhesive tape can be further improved and the adherend can be more reliably fixed.
The tacky fire is not particularly limited, but it is preferable to be a hydrogenated petroleum-based and/or terpene phenol-based tacky fire, since it is possible to further improve the adhesive strength, and it is more preferable to be a hydrogenated petroleum-based tacky fire. preferable. Of these, an alicyclic saturated hydrocarbon tacky fire is more preferable. This is because the alicyclic saturated hydrocarbon tacky fire, which has a low affinity with the stripping solution, can be used to more effectively penetrate the stripping solution into the interface between the adhesive tape and the adherend. The peeling can be made more effective. The hydrogenation rate of the tacky fire is preferably 95% or more, more preferably 96% or more. The upper limit of the hydrogenation rate of the tacky fire is usually 100% or less.

The preferable lower limit of the content of the tacky fire with respect to 100 parts by weight of the styrene-based elastomer is 10 parts by weight, and the more preferable lower limit is 20 parts by weight. The preferable upper limit of the content of the tacky fire is 100 parts by weight, and the more preferable upper limit is 100 parts by weight, relative to 100 parts by weight of the styrene-based elastomer.

The pressure-sensitive adhesive layer may further contain additives such as a softening agent, an antioxidant, an anti-adhesive agent, and a release agent, if necessary.

The thickness of the pressure-sensitive adhesive layer is not particularly limited, but the preferred lower limit is 5 μm, the more preferred lower limit is 8 μm, the still more preferred lower limit is 10 μm, the preferred upper limit is 500 μm, and the more preferred upper limit is 300 μm. When the thickness of the pressure-sensitive adhesive layer is within this range, the weight of the electronic component including the pressure-sensitive adhesive tape can be reduced, and the pressure-sensitive adhesive tape having sufficient adhesive force and handleability can be obtained.

The adhesive tape may be a support type having a base material layer or a non-support type having no base material layer. When the pressure-sensitive adhesive tape has a base material layer, it is preferably a double-sided pressure-sensitive adhesive tape having a base material layer and a pressure-sensitive adhesive layer on both surfaces of the base material layer.

When the pressure-sensitive adhesive tape has a base material layer, the raw material for the base material layer is not particularly limited, and examples thereof include polyethylene, polypropylene, polyethylene terephthalate, α-olefin copolymer, polyurethane, and styrene elastomer. Among them, the raw material of the base material layer is polyethylene, polypropylene, from the viewpoint of becoming a pressure-sensitive adhesive tape having more excellent tensile rupture strength and tensile rupture elongation, and suppressing delamination between the base material layer and the pressure-sensitive adhesive layer. It preferably contains at least one selected from the group consisting of polyethylene terephthalate, α-olefin copolymer, polyester and polyurethane. Further, it is more preferable to contain at least one selected from the group consisting of polyethylene, polypropylene and polyethylene terephthalate. The raw material of the base material layer may be only one kind or two or more kinds.

The thickness of the base material layer is not particularly limited, but a preferred lower limit is 10 μm, and a more preferred lower limit is 20 μm. When the thickness of the base material layer is equal to or more than the above lower limit, the strength of the obtained adhesive tape is improved, and it becomes difficult to tear the adhesive tape during peeling. The upper limit of the thickness of the base material layer is not particularly limited, but is preferably 1 mm or less. When the thickness of the base material layer is equal to or less than the upper limit, the weight of the electronic component including the pressure-sensitive adhesive tape can be reduced, and the double-sided pressure-sensitive adhesive tape having excellent flexibility and handleability can be obtained.

The adhesive tape preferably has a peel strength of 8 N/25 mm or more with respect to the stainless steel plate, and a peel strength of 6 N/25 mm or less with respect to the stainless steel plate after being immersed in a peeling solution for 30 seconds.
When the peeling strength before being immersed in the peeling solution is 8 N/25 mm or more, the adherend can be fixed with sufficient adhesive force. When the peel strength after immersion in the peeling solution is 6 N/25 mm or less, damage can be suppressed and the adherend can be peeled from the adhesive tape. From the viewpoint of further improving the adhesive force, the peel strength with respect to the stainless steel plate is more preferably 10 N/25 mm or more, and further preferably 12 N/25 mm or more. The upper limit of the peel strength for the stainless steel plate is not particularly limited, and the higher the better, the better, but the limit is about 35 N/25 mm.
Further, from the viewpoint of suppressing damage to the adherend and peeling the adherend from the adhesive tape with a lighter force, the peel strength with respect to the stainless steel plate after being immersed in the peeling liquid for 30 seconds is 4 N/25 mm or less. More preferably, it is more preferably 3 N/25 mm or less. The lower limit of the peel strength with respect to the stainless steel plate after being immersed in the peeling solution for 30 seconds is not particularly limited, and the lower the better, the better, but the limit is about 0.05 N/25 mm. The peel strength is measured by using a stainless steel plate (SUS304) conforming to JIS G4305 and JIS B0601 as an adherend and performing a tensile test in a 180° direction at a peeling speed of 300 mm/min according to JIS Z0237. can do.

The pressure-sensitive adhesive layer has a peel strength with respect to a stainless steel plate after being immersed in a peeling liquid having an SP value of 22.0 or less for 30 seconds, which is 0.5 times or less than a peel strength with respect to the stainless steel plate before being immersed in the peeling liquid. Is preferred.
When the adhesive strength of the pressure-sensitive adhesive layer after immersion in the peeling solution is within the above range, damage to the adherend can be suppressed and the adherend can be separated from the adhesive tape. The peel strength of the pressure-sensitive adhesive layer after immersion in the peeling solution is preferably 0.2 times or less, and more preferably 0.1 times or less, the peel strength before immersion in the peeling solution. The lower limit of the peeling strength of the pressure-sensitive adhesive layer after immersion in the peeling solution is not particularly limited, and the lower the better, the better. The peeling strength can be adjusted by the type of the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer and the content of additives such as tacky fire.
The peel strength of the pressure-sensitive adhesive layer can be measured by the same method as the peel strength. As the stripper having the SP value of 22.0 or less, the same stripper as described below can be used.

The method for producing the pressure-sensitive adhesive tape is not particularly limited, for example, by applying a solution of the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer on the release film, and drying, to manufacture a non-support type pressure-sensitive adhesive tape. You can When the pressure-sensitive adhesive tape of the present invention is a support type having a base material layer, a pressure-sensitive adhesive layer is formed separately from the above-mentioned pressure-sensitive adhesive layer, and two pressure-sensitive adhesive layers and a base material layer are bonded to each other. It can be manufactured. Further, it can be produced by a coextrusion laminating method.

The coextrusion laminating method is a manufacturing method in which a base material layer and an adhesive layer are simultaneously formed by extruding a base material resin and a pressure sensitive adhesive resin with a coextrusion machine. There is no contamination and the cost is low because the adhesive tape can be manufactured in one step.
When the pressure-sensitive adhesive tape is manufactured by the coextrusion laminating method, a transition layer is formed between the base material layer and the pressure-sensitive adhesive layer. The transition layer refers to a layer in which the components of the base material layer and the components of the pressure-sensitive adhesive layer are gradually replaced with each other from the base material layer side to the pressure-sensitive adhesive layer side. The presence of the transition layer was obtained by cutting out a cross section of the double-sided pressure-sensitive adhesive tape using a microtome, making it a test sample for observation, and changing the hardness at the interface between the base material layer and the pressure-sensitive adhesive layer with a scanning probe microscope (SPM). It can be confirmed by observing and the hardness changes continuously. It can also be confirmed by observing a change in the phase separation structure at the interface between the base material layer and the pressure-sensitive adhesive layer with a transmission electron microscope (TEM). For example, when the pressure-sensitive adhesive layer contains a styrene-based elastomer and has a phase-separated structure having a spherical styrene segment in the molecule, when the transition layer is present, the spherical styrene segment in the pressure-sensitive adhesive layer approaches the base material layer. As the size decreases, the density of spherical styrene segments decreases.

The stripper has an SP value of 22.0 or less.
By using the above-mentioned styrene-based elastomer for the pressure-sensitive adhesive layer of the pressure-sensitive adhesive tape and having a SP value of 22.0 or less as the peeling liquid, the peeling liquid permeates between the pressure-sensitive adhesive layer and the adherend, and the pressure-sensitive adhesive tape It is possible to reduce the adhesive strength of the adherend, suppress the damage to the adherend, and peel the adherend from the adhesive tape. Further, by using the styrene-based elastomer and the release liquid, the styrene-based elastomer is unlikely to dissolve in the release liquid, and the adherend is less likely to be contaminated by the adhesive. From the viewpoint of further lowering the adhesive strength of the pressure-sensitive adhesive tape and making it more difficult to contaminate the adherend, the preferable upper limit is 20.0, and the more preferable upper limit is 15.0. The lower limit of the SP value is not particularly limited, but a preferable lower limit is 7.0 and a more preferable lower limit is 9.0 from the viewpoint of further lowering the adhesive force of the pressure-sensitive adhesive tape and making the adherend less likely to be contaminated. ..

The SP value is called a solubility parameter (Solubility Parameter), and is an index that can express the ease of dissolution. In the present specification, the Fedors method (RF Fedors, Polym. Eng. Sci., 14(2), 147-154 (1974)) is used to calculate the SP value. When the stripping solution is a mixed solution, the SP value of the mixed solution is obtained by multiplying the SP value of each component by the content ratio of the component and adding them together.

The stripping solution is not particularly limited as long as it satisfies the SP value range, and examples thereof include alcohol, ester, and aromatic hydrocarbon. Among them, the peeling liquid preferably contains at least one selected from the group consisting of alcohols and esters because the adherend can be peeled off from the adhesive tape while further suppressing the damage to the adherend. Examples of the alcohol include methanol, ethanol, propanol, isopropanol and the like, and among them, ethanol and isopropanol are preferable. Examples of the ester include ethyl acetate and butyl acetate, and among them, ethyl acetate is preferable.

The pressure-sensitive adhesive tape used in the method for peeling off the pressure-sensitive adhesive tape of the present invention is not particularly limited as long as it has a pressure-sensitive adhesive tape containing the styrene elastomer. As a specific example of the pressure-sensitive adhesive tape, for example, the pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer containing a styrene-based elastomer and treated with a release liquid having an SP value of 22.0 or less has a peel strength of SP value 22. Adhesive tapes having a peel strength of 0.5 times or less of the pressure-sensitive adhesive tape before being treated with a stripping solution of 0.0 or less are mentioned. Such an adhesive tape is also one aspect of the present invention.

The adhesive tape of the present invention has an adhesive layer containing a styrene elastomer.
As for the specific type of the styrene-based elastomer, the type and content of additives such as tacky fire, and the thickness of the pressure-sensitive adhesive layer, the same one as the pressure-sensitive adhesive layer in the method for peeling the pressure-sensitive adhesive tape of the present invention may be used. it can.

The pressure-sensitive adhesive tape of the present invention may be a support type having a base material layer or a non-support type not having a base material layer, but an adherend whose strength is required for the pressure-sensitive adhesive tape When used for, it is preferable to have a base material layer.
As for the type and thickness of the base material layer, the same material and thickness as the base material layer in the method for peeling an adhesive tape of the present invention can be used.

When the adhesive tape of the present invention has a base material layer, the adhesive tape of the present invention is preferably an adhesive tape in which an adhesive layer, a base material layer, and a second adhesive layer are laminated in this order. The pressure-sensitive adhesive forming the second pressure-sensitive adhesive layer is not particularly limited, and may be the same as or different from the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer. Of these, an acrylic pressure-sensitive adhesive is preferable because it is easy to satisfy the peel strength described below.

It is preferable that the pressure-sensitive adhesive layer has a first surface and a second surface opposite to the first surface, and the first surface has an embossed shape.
By sticking the first surface having the embossed shape to an adherend to be recovered later, when the peeling solution is brought into contact with the adherend, the peeling solution spreads over the entire first surface through the embossed groove. it can. Therefore, when the adhesive tape is attached to a large area in order to fix the large-sized parts, particularly when the large-sized hard parts are fixed to each other, high peelability can be exhibited. When the adhesive tape of the present invention has a base material layer, the first surface is the surface opposite to the surface on which the base material layer is laminated, that is, the surface in contact with the adherend. The 2 surface refers to the surface on which the base material layers are laminated.

It is preferable that the embossed shape is formed by a plurality of grooves that are connected from one end to the other side surface of the pressure-sensitive adhesive layer.
When the embossed shape is composed of a plurality of grooves penetrating in the surface direction of the pressure-sensitive adhesive layer, the peeling liquid permeates the entire first surface of the pressure-sensitive adhesive layer by bringing the peeling liquid into contact with the side surface of the pressure-sensitive adhesive layer. The peelability can be improved.

The groove is preferably linear.
Since the groove is linear, the peeling liquid is less likely to be caught when passing through the groove, and the peeling liquid can more smoothly permeate the entire first surface. Further, it is preferable that the embossed shape includes a first groove and a second groove that intersects with the first groove. By using a combination of a plurality of grooves that intersect the embossed shape, preferably a plurality of linear grooves that intersect, the stripper can be more evenly and efficiently permeated into the entire first surface. Examples of the shape of such embossing include a lattice shape.

The depth of the groove forming the embossed shape is preferably 8 μm or more.
When the depth of the groove forming the embossed shape is within the above range, the peeling liquid can more smoothly permeate the entire first surface. More preferably, the depth of the groove is 10 μm or more. The upper limit of the depth of the groove is not particularly limited, but when the pressure-sensitive adhesive tape of the present invention does not have a base material layer, the depth is preferably 80% or less of the thickness of the pressure-sensitive adhesive layer, and the base material layer. When it has, it may be the same as the thickness of the pressure-sensitive adhesive layer.

The width of the groove forming the embossed shape is preferably 10 μm or more and 500 μm or less.
When the width of the groove forming the embossed shape is within the above range, the peeling liquid can more smoothly permeate the entire first surface. The width of the groove is more preferably 30 μm or more, and more preferably 150 μm or less.

The proportion of the grooves forming the embossed shape on the first surface is preferably 10% or more and 50% or less.
By forming the groove forming the embossed shape in the area within the above range, the adherend can be more reliably fixed, and the peeling liquid can more smoothly permeate the entire first surface during peeling. The area of the groove is more preferably 15% or more, and more preferably 40% or less.

The method of forming the embossed shape on the first surface is not particularly limited, and for example, a method of applying a pressure-sensitive adhesive to a release paper having a convex shape in a lattice shape and drying it to transfer the shape, , A release paper having a convex shape in a lattice shape is attached to a molded adhesive tape, and the shape is transferred over a period of time.

The pressure-sensitive adhesive layer has a peel strength for a stainless steel plate after being immersed in a peeling solution having an SP value of 22.0 or less for 30 seconds, which is 0.5 times or less of a peel strength for a stainless steel plate before being immersed in the peeling liquid.
When the adhesive strength of the pressure-sensitive adhesive layer after immersion in the peeling solution is within the above range, damage to the adherend can be suppressed and the adherend can be separated from the adhesive tape. The peel strength of the pressure-sensitive adhesive layer after immersion in the peeling solution is preferably 0.2 times or less, and more preferably 0.1 times or less, the peel strength before immersion in the peeling solution. The lower limit of the peeling strength of the pressure-sensitive adhesive layer after immersion in the peeling solution is not particularly limited, and the lower the better, the better. The peeling strength can be adjusted by the type of the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer and the content of additives such as tacky fire.
The peel strength of the pressure-sensitive adhesive layer can be measured by the same method as the peel strength in the pressure-sensitive adhesive tape peeling method of the present invention. Further, as the peeling liquid having the SP value of 22.0 or less, the same peeling liquid as used in the method for peeling an adhesive tape of the present invention can be used.

The pressure-sensitive adhesive layer preferably has a peel strength of 5 N/25 mm or more with respect to stainless steel before being immersed in the peeling liquid having an SP value of 22.0 or less.
When the peel strength of the pressure-sensitive adhesive layer before immersion in the peeling solution is within the above range, the adherend can be more firmly fixed. The peel strength of the pressure-sensitive adhesive layer before immersion in the above-mentioned stripping solution is more preferably 8 N/25 mm or more, further preferably 10 N/25 mm or more. The upper limit of the peel strength of the pressure-sensitive adhesive layer before immersion in the peeling solution is not particularly limited, but is preferably 35 N/25 mm from the viewpoint of handleability.

The pressure-sensitive adhesive layer preferably has a peel strength of 3 N/25 mm or less with respect to stainless steel after being immersed in the peeling solution having the SP value of 22.0 or less.
When the peel strength of the pressure-sensitive adhesive layer after immersion in the peeling solution is within the above range, the pressure-sensitive adhesive tape can be peeled off while further suppressing damage to the adherend. The peel strength of the pressure-sensitive adhesive layer after immersion in the above-mentioned peeling liquid is more preferably 1 N/25 mm or less, and further preferably 0.7 N/25 mm or less. The lower limit of the peeling strength of the pressure-sensitive adhesive layer before immersion in the peeling solution is not particularly limited, but is preferably 0.05 N/25 mm from the viewpoint of balance with the adhesive strength.

The second pressure-sensitive adhesive layer has a peel strength with respect to a stainless steel plate after being immersed in a peeling liquid having an SP value of 22.0 or less for 30 seconds that is greater than 0.5 times the peel strength with respect to the stainless steel plate before being immersed in the peeling liquid. Is preferred.
By making the peel strength of the second pressure-sensitive adhesive layer larger than the peel strength of the pressure-sensitive adhesive layer, peeling can be more reliably caused at the interface between the pressure-sensitive adhesive layer and the adherend to be collected. .. The peel strength of the second pressure-sensitive adhesive layer can be adjusted by the type of the pressure-sensitive adhesive layer forming the second pressure-sensitive adhesive layer and additives such as tacky fire.
The peel strength of the second pressure-sensitive adhesive layer can be measured by the same method as the peel strength in the peeling method of the pressure-sensitive adhesive tape of the present invention. Further, as the peeling liquid having the SP value of 22.0 or less, the same peeling liquid as used in the method for peeling an adhesive tape of the present invention can be used.

The thickness of the second pressure-sensitive adhesive layer is not particularly limited, but the preferred lower limit is 5 μm, the more preferred lower limit is 8 μm, the still more preferred lower limit is 10 μm, the preferred upper limit is 200 μm, and the more preferred upper limit is 150 μm. When the thickness of the second pressure-sensitive adhesive layer is within this range, the weight of the electronic component including the pressure-sensitive adhesive tape can be reduced, and the pressure-sensitive adhesive tape having sufficient pressure-sensitive adhesive force and handleability can be obtained.

When the pressure-sensitive adhesive tape of the present invention has the embossed shape, it is preferable that the pressure-sensitive adhesive layer has a release film having protrusions corresponding to the embossed grooves on the first surface.
By protecting the pressure-sensitive adhesive layer with a release film having a convex portion that fills the embossed groove, it is possible to prevent the groove from being crushed or deformed during storage or transportation, and thus it is possible to suppress deterioration of the peeling performance. it can. The material of the release film is not particularly limited, and for example, a release film of a normal adhesive tape such as a release-treated polyethylene terephthalate film, release-treated clean paper or paper laminated with polyethylene or polypropylene. The materials used as are.

The method for producing the release film is not particularly limited, and examples thereof include extrusion film formation.

The thickness of the pressure-sensitive adhesive tape is not particularly limited, but the preferred lower limit is 20 μm, the more preferred lower limit is 30 μm, the preferred upper limit is 1.7 mm, the more preferred upper limit is 500 μm, and the still more preferred upper limit is 250 μm. When the thickness of the pressure-sensitive adhesive tape is in the above range, the weight of the electronic component including the pressure-sensitive adhesive tape can be reduced, and the pressure-sensitive adhesive tape having sufficient adhesive force and handleability can be obtained.

The method for producing the pressure-sensitive adhesive tape of the present invention is not particularly limited, for example, by applying a solution of the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer on the release film produced by the above method, and drying, a non-support type It can be manufactured as an adhesive tape. When the pressure-sensitive adhesive tape of the present invention is a support type having a base material layer, a solution of the pressure-sensitive adhesive constituting the second pressure-sensitive adhesive layer is applied on a release film, and dried, separately from the pressure-sensitive adhesive layer. Then, the second pressure-sensitive adhesive layer is formed, and the pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer are bonded to the base material layer, respectively. Further, it can be produced by the coextrusion laminating method as described above.

Here, a schematic diagram showing an example of the adhesive tape of the present invention is shown in FIG. 1, and a schematic diagram showing an example of a cross section of the adhesive tape of the present invention is shown in FIG. 1 and 2 show an example of an adhesive tape having an adhesive layer, a base material layer, and a second adhesive layer.
As shown in FIG. 1, the pressure-sensitive adhesive tape of the present invention has a pressure-sensitive adhesive layer 1 having a first surface 11 and a second surface 12, a base material layer 2, and a second pressure-sensitive adhesive layer 3. By setting the peel strength of the pressure-sensitive adhesive layer 1 to stainless steel within the above range before and after the immersion in the peeling solution, the adherend can be firmly fixed, while after being brought into contact with the peeling solution, the adhesion of the adherend is suppressed and the adhesion is suppressed. The tape can be easily peeled off.

Further, as shown in FIG. 2(a), the pressure-sensitive adhesive tape of the present invention may be flat as long as it satisfies the above peel strength, but as shown in FIGS. It is preferable to have the embossed shape 13 on the first surface 11 in contact with the body. Since the pressure-sensitive adhesive layer 1 has the embossed shape 13, when the peeling liquid is brought into contact with the side surface of the pressure-sensitive adhesive layer 1, the peeling liquid permeates the entire first surface 11 through the grooves forming the embossed shape. Even if the adhesive tape is used in a large area for fixing hard and large parts, the adhesive tape can be easily peeled off while suppressing damage to the adherend. In particular, when the embossed groove 14 is a plurality of grooves which are connected from one end to the other on the side surface of the pressure-sensitive adhesive layer 1 as shown in FIG. 1, particularly a linear groove having a width and a depth in the above range, a peeling liquid is used. Can be more easily penetrated into the entire first surface 11, and the releasability can be further enhanced. In addition, by setting the proportion of the grooves forming the embossed shape on the first surface 11 within the above range, the adherend can be more reliably fixed and the peelability can be improved.

Further, as shown in FIG. 2B, when the pressure-sensitive adhesive layer 1 has the embossed shape 13, it is preferable to have the release film 4 having the protrusions 41 corresponding to the embossed grooves. By protecting the embossed shape 13 with such a release film, the embossed groove 14 is less likely to be deformed during movement or storage, so that the peeling liquid can be less likely to be clogged when brought into contact with the peeling liquid. .. Although not shown, the second pressure-sensitive adhesive layer 3 may also be protected by a release film as in a normal pressure-sensitive adhesive tape.

In the pressure-sensitive adhesive tape of the present invention, the base material layer 2 and the second pressure-sensitive adhesive layer 3 may or may not be provided, but the strength and handleability are improved by having the base material layer 2. Can be made Further, when the difference between the peel strength of the second pressure-sensitive adhesive layer with respect to the stainless steel before immersion in the peeling liquid and the peel strength with respect to the stainless steel after immersion of the peeling liquid is within the above range, the interface between the adherend and the adhesive tape that should be collected more reliably It can cause peeling.

The method for peeling off the pressure-sensitive adhesive tape of the present invention and the field of use of the pressure-sensitive adhesive tape of the present invention are not particularly limited, but since it is difficult to damage the adherend, from an electronic device having an electronic component fixed by the pressure-sensitive adhesive tape to the electronic component Can be suitably used when peeling. Among them, it can be used particularly preferably when peeling a battery pack used in a portable electronic device such as a smartphone or a tablet. The battery pack and the case are becoming thinner, and the strength thereof is not so high, so that the possibility of damage at the time of peeling increases. However, by using the peeling method of the present invention and the adhesive tape of the present invention, it is possible to perform peeling while suppressing damage to the battery pack and the casing at the time of peeling. In addition, since the battery pack is covered by the cover, there is no risk that it will be peeled off by the liquid that has entered through the gap of the smartphone etc., and the adhesive strength of the adhesive tape may remain high without decreasing. Therefore, the present invention is particularly effective. Further, when the pressure-sensitive adhesive tape of the present invention has an embossed shape, the peelability is further enhanced, so that not only the fixing of electronic components used in a portable electronic device or the like having a relatively small area but also the large-area electronic device Even when the adhesive tape is used for fixing components, the adhesive tape can be peeled off while suppressing damage to the members.
An electronic component having such an adhesive tape of the present invention is also one aspect of the present invention.

ADVANTAGE OF THE INVENTION According to this invention, the peeling method of the adhesive tape which is hard to be damaged at the time of collecting the components fixed by the adhesive tape, the adhesive tape used for the peeling method, and the electronic component using the adhesive tape used for the peeling method Can be provided.

It is a figure showing an example of the adhesive tape of the present invention. (A) It is a schematic diagram showing an example of the cross section of the adhesive tape of this invention. (B) It is a schematic diagram showing an example of the cross section of the adhesive tape of this invention.

Hereinafter, the embodiments of the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

(1) Base resin for pressure-sensitive adhesive layer The following commercially available products and the compound synthesized by the following method were used as the base resin for the pressure-sensitive adhesive layer.
(Commercial goods)
・DR8300P: Styrene-based elastomer (SEBS) with hydrogenation, manufactured by JSR ・DR8903P: Styrene-based elastomer (SEBS) with hydrogen, manufactured by JSR ・DR9901P: Styrene-based elastomer (SEBS) with hydrogenation, JSR Made / Septon 2063: Styrene-based elastomer (SEPS), with hydrogenation, Kuraray Co., Ltd. / Quintac 3421: Styrene-based elastomer (SIS), without hydrogenation, made by Zeon Corporation / Natural rubber: RSS1
-OPPANOL N50: polyisobutylene, manufactured by BASF

(Synthesis of acrylic compound)
52 parts by weight of ethyl acetate was put into a reactor equipped with a thermometer, a stirrer, and a cooling tube, and after purging with nitrogen, the reactor was heated to start reflux. Thirty minutes after the boiling of ethyl acetate, 0.08 part by weight of azobisisobutyronitrile was added as a polymerization initiator. A monomer mixture consisting of 18.5 parts by weight of butyl acrylate, 80 parts by weight of 2-ethylhexyl acrylate, 1 part by weight of acrylic acid, and 0.5 parts by weight of 2-hydroxyethyl acrylate was added uniformly and gradually over 1 hour and 30 minutes. It was dropped and reacted. Thirty minutes after the end of the dropping, 0.1 part by weight of azobisisobutyronitrile was added, and the polymerization reaction was further performed for 5 hours. By adding ethyl acetate in the reactor and cooling it while diluting, solid content of 40% by weight was obtained. A solution of the acrylic formulation was obtained. When the weight average molecular weight of the obtained acrylic compound solution was measured by GPC method using "2690 Separations Model" manufactured by Water Co. as a column, the weight average molecular weight of the solid content was 250,000.

(2) Base Resin for Base Layer The following was used as the base resin for the base layer.
・Toughmer PN-0040: α-polyolefin resin, manufactured by Mitsui Chemicals Inc. ・J715: Polypropylene resin, manufactured by Prime Polymer Cosmoshine A4300: Polyethylene terephthalate film, thickness 50 μm, manufactured by Toyobo Co., Ltd. ・Polyurethane: NES85, manufactured by Okura Industry Co., Ltd.

(3) Tackifier (Tacky Fire)
The following tackifiers were used in the pressure-sensitive adhesive layer.
・Alcon P-100: Petroleum-based tackifier, Arakawa Chemical Co., Ltd. ・Alcon P-125: Petroleum-based tackifier, Arakawa Chemical Co., Ltd. ・Arcon P-140: Petroleum-based tackifier, Arakawa Chemical Co., Ltd. Tuck PT90HS: C5-C9 petroleum-based tackifier, Tosoh Corp., YS Polystar UH115: Terpene phenolic tackifier, Yasuhara Chemical Co., A100: Rosin ester tackifier, Arakawa Chemical Co., Ltd.

(Example 1)
100 parts by weight of DR8300P, 40 parts by weight of Alcon P100 and 1 part by weight of an antioxidant (IRGANOX 1010, manufactured by BASF) were mixed to obtain an adhesive composition for forming an adhesive layer. .. Both sides of the base material layer having a thickness of 50 μm were formed by coextrusion molding using the T-die method using the above-mentioned Toughmer PN-0040 as the base material layer and the adhesive composition obtained above as the raw material for the adhesive layer. A double-sided pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer having a thickness of 30 μm was obtained. Before winding, the release-treated PET separator was laminated on both sides and wound to obtain a roll-shaped double-sided adhesive tape. The presence or absence of the phase separation structure was confirmed by observing the pressure-sensitive adhesive layer of the obtained pressure-sensitive adhesive tape with a transmission electron microscope JEM-2100 (manufactured by JEOL Ltd.).

(Measurement of peel strength before immersion in peeling solution)
The obtained double-sided adhesive tape was cut into 25 mm wide strips to prepare test pieces. The test piece was placed on a stainless steel plate (SUS304, No. 360 water-resistant abrasive paper surface-polished, size 50 mm×125 mm) in accordance with JIS G4305 and JIS B0601 so that the pressure-sensitive adhesive layer faced the stainless steel plate. .. Then, the test piece and the stainless steel plate were bonded together by reciprocating a 2 kg rubber roller on the test piece at a speed of 300 mm/min. Further, according to JIS Z0237, a polyethylene terephthalate film specified in JIS C2318 having a nominal thickness of 25 μm is superposed on the test piece, and another 2 kg rubber roller is reciprocated on the film at a speed of 300 mm/min to make 180°. A test sample for peel strength evaluation was used. After that, using a tensile tester (STA1225, manufactured by AND Co., Ltd.), the sample was allowed to stand at a temperature of 23° C. and a humidity of 50% for 24 hours, and a tensile test was performed in a 180° direction at a peeling rate of 300 mm/min according to JIS Z0237. The peel strength (A) (N/25 mm) of the pressure-sensitive adhesive layer before immersion in the peeling solution was measured.
Next, the same operation was performed except that the adhesive layer to be attached to the stainless steel plate was the second adhesive layer, and the peel strength (A) (N/25 mm) of the second adhesive layer before immersion in the release liquid was measured. ..

(Measurement of peeling strength after immersion in peeling solution)
Before performing the tensile test in the 180° direction, 2 mL of the stripping solution (ethanol, SP value 12.7) was dropped around the adhesive tape of the test sample for evaluation using a dropper, and the peel strength was the same as the above except that it was immersed for 30 seconds. The peeling strength (B) of the pressure-sensitive adhesive layer after immersion in the peeling solution was measured by the same method as in the above measurement. Next, the same operation was performed except that the second pressure-sensitive adhesive layer was used as the pressure-sensitive adhesive layer attached to the stainless steel plate, and the peel strength (B) (N/25 mm) of the second pressure-sensitive adhesive layer after immersion in the peeling solution was measured. .. The value of B/A was calculated from the obtained peel strength (A) before immersion in the peeling solution and the peel strength (B) after immersion in the peeling solution.

(Examples 4, 6 to 12, Comparative Example 3)
A double-sided pressure-sensitive adhesive tape was obtained in the same manner as in Example 1 except that the composition of the pressure-sensitive adhesive layer, the thickness, the base resin of the base material, and the stripping solution were changed as shown in Tables 1 and 3, and the presence/absence of a phase separation structure was confirmed. The peel strength was measured.

(Example 2)
The pressure-sensitive adhesive composition obtained in Example 1 was extrusion-molded to obtain a non-support type double-sided pressure-sensitive adhesive tape having a thickness of 100 μm, and each peel strength was measured. The presence or absence of the phase separation structure was confirmed by observing the pressure-sensitive adhesive layer of the obtained pressure-sensitive adhesive tape with a transmission electron microscope JEM-2100 (manufactured by JEOL Ltd.). The obtained double-sided pressure-sensitive adhesive tape was protected on both sides with a light-peelable release PET film until use.

(Example 3)
DR8300P was dissolved in toluene so that the solid content was 30%, and 40 parts by weight of Alcon P100 was added to 100 parts by weight of the solid content to obtain a pressure-sensitive adhesive composition. The obtained pressure-sensitive adhesive composition was applied onto one surface of the base material layer, Cosmoshine A4300, so that the thickness after drying was 30 μm, and dried at 100 to 130° C. for 7 minutes to obtain a single-sided pressure-sensitive adhesive tape. .. In the obtained single-sided adhesive tape, a light release type release PET film was laminated on the adhesive layer to protect the adhesive layer. After that, a second pressure-sensitive adhesive layer was formed on the other surface of the base material layer by the same method, and a light-release type release PET film was laminated to obtain a double-sided pressure-sensitive adhesive tape. The presence or absence of the phase separation structure was confirmed by observing the adhesive layer and the second adhesive layer of the obtained adhesive tape with a transmission electron microscope JEM-2100 (manufactured by JEOL Ltd.). Each peel strength of the obtained double-sided pressure-sensitive adhesive tape was measured in the same manner as in Example 1.

(Examples 17 to 28, Comparative Example 5)
The type of base resin, the type of tackifier, and the compounding amount are as shown in Tables 2 and 3, and a double-sided pressure-sensitive adhesive tape was obtained in the same manner as in Example 3 except that the base material layer was not used. Was confirmed and each peel strength was measured.

(Examples 5, 13 to 16, Reference Example 1)
A double-sided pressure-sensitive adhesive tape was obtained in the same manner as in Example 3 except that the composition of the pressure-sensitive adhesive layer, the thickness, the base resin of the base material, and the stripping solution were changed as shown in Tables 1 to 3, and the presence or absence of a phase separation structure was confirmed. The peel strength was measured. As the stripping solution of Example 16, an ethanol/water mixed solution (ethanol:water=20:80) was used.

(Example 29)
A release film having a square lattice-shaped embossed shape composed of a plurality of convex portions made of polyethylene on one surface of clean paper was prepared. The protrusions are linear and continuous from one end of the clean paper to the end of the opposite side, and the protrusions are arranged at equal intervals. The height of the protrusions is 5 μm, the width is 50 μm, and the ratio of the protrusions to the surface of the release film is 10%. The embossed surface of this release film was coated with the adhesive composition in the same manner as in Example 3 and dried to form an adhesive layer having a thickness of 50 μm and having an embossed shape in which the convex portions were grooves. Formed. Thereafter, a light release type release PET film was laminated on the pressure-sensitive adhesive layer to obtain a double-sided pressure-sensitive adhesive tape. With respect to the obtained double-sided pressure-sensitive adhesive tape, the presence/absence of a phase-separated structure was confirmed and the peel strengths were measured in the same manner as in Example 1.

(Examples 30 to 33)
A double-sided pressure-sensitive adhesive tape was obtained in the same manner as in Example 29 except that the embossed shape of the release film and the type of base resin were changed as shown in Table 3. It should be noted that the embossing 2 has a shape in which the groove of FIG. 1 is a convex portion, the embossing 3 has the same shape as the embossing 1, and the embossing 2 is a convex portion having a height of 20 μm and a width of 70 μm. The proportion of the convex portion occupying is 20%. The emboss 3 is composed of a convex portion having a height of 15 μm and a width of 8 μm, and the proportion of the convex portion on the surface of the release film is 15%. Further, the random embossing has a shape in which irregularities appear irregularly and does not have a specific width or height.

(Example 34)
An adhesive layer was formed in the same manner as in Example 29 except that the embossed shape of the release film was the same as that in Example 30 and the thickness was 30 μm. Then, Cosmoshine A4300 was laminated as a base material layer on the obtained pressure-sensitive adhesive layer. On the other hand, a second pressure-sensitive adhesive layer was formed in the same manner as the pressure-sensitive adhesive layer on another light-releasing release film. The obtained second adhesive layer and the surface of the base material layer on which the adhesive layer was not laminated were laminated to obtain a double-sided adhesive tape.

(Examples 35 and 36, Comparative Examples 2 and 6)
A double-sided pressure-sensitive adhesive tape was obtained in the same manner as in Example 34 except that the base resin, tackifier, and base material used were as shown in Table 3, and the presence or absence of a phase separation structure was confirmed and the peel strengths were measured.

(Comparative Example 1)
0.5 parts by weight of isocyanate (trade name "Coronate HX", manufactured by Tosoh Corporation) was mixed with the acrylic compound solution, and the mixture was stirred for 30 minutes to obtain a pressure-sensitive adhesive composition. A double-sided pressure-sensitive adhesive tape was obtained in the same manner as in Example 3 except that the obtained pressure-sensitive adhesive composition was used, and the presence or absence of a phase separation structure was confirmed and the peel strengths were measured.

(Comparative example 4)
A double-sided pressure-sensitive adhesive tape was obtained in the same manner as in Example 30 except that the pressure-sensitive adhesive composition of Comparative Example 1 was used, and the presence or absence of a phase separation structure was confirmed and the peel strengths were measured.

<Evaluation>
The adhesive tapes obtained in Examples and Comparative Examples were evaluated by the following methods.
The results are shown in Tables 1 to 3.

(1) Evaluation of peelability 1
Laminated lithium-ion battery pack (80 mm x 40 mm, area 32 cm ² , hereafter referred to as battery pack) via the double-sided adhesive tape obtained on the smartphone casing (hereinafter referred to as casing) whose surface is stainless Pasted Then, 2 ml of the stripping solution shown in Tables 1 to 3 was poured from the gap between the battery pack and the case using a dropper to bring the adhesive layer into contact with the stripping solution. After 30 seconds, a pick was inserted into the gap between the battery pack and the case, and the pick was pushed up to separate the battery pack from the case. Repeated the same test three times, “○” indicates that the battery pack could be peeled off without damaging the battery pack three times, “△” indicates that the battery pack was damaged once, and the battery pack was damaged twice or three times. The peelability 1 was evaluated as "x" when it did.

(2) Evaluation of adhesive residue 1
Visually observing the battery pack after peelability evaluation, "○" when there is no adhesive residue, "△" when there is adhesive residue on a part, and when adhesive residue is seen on the whole The adhesive residue 1 was evaluated as "x".

(3) Evaluation of peelability 2
The pressure-sensitive adhesive layer side of the obtained double-sided pressure-sensitive adhesive tape was attached to a silicon wafer (area: 314 cm ² ) having a diameter of 8 inches, and glass (8 inches, 2 mm thickness) was attached to the opposite surface. Then, 5 ml of the stripping solution shown in Tables 1 to 3 was poured into the side surface of the double-sided adhesive tape to bring the pressure-sensitive adhesive layer into contact with the stripping solution. Ten seconds later, a pick was inserted between the glass and the silicon wafer, and the pick was pushed up to peel off the glass. Repeated the same test three times, "○" indicates that the glass could be peeled without breaking the glass three times, and "○" indicates that the glass could be peeled without breaking the glass once or twice. The peelability 2 was evaluated as "Δ" when the peeling itself was possible and "X" when the peeling was not possible.

(4) Evaluation of adhesive residue 2
After visually observing the glass after peelability evaluation, "O" indicates that there is no adhesive residue, "△" indicates that adhesive residue is partially observed, and "Adhesive residue" is observed when the entire adhesive residue is observed. The adhesive residue 2 was evaluated as "x".

DESCRIPTION OF SYMBOLS 1 Adhesive layer 11 1st surface 12 2nd surface 13 Embossed shape 14 Embossed groove 2 Base material layer 3 2nd adhesive layer 4 Release film 41 Convex part corresponding to embossed groove

Claims

A pressure-sensitive adhesive layer of a laminate in which a pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer containing a styrene-based elastomer is adhered to the pressure-sensitive adhesive layer, and a peeling liquid having an SP value of 22.0 or less is brought into contact with the pressure-sensitive adhesive layer, and then the pressure-sensitive adhesive layer A method for peeling an adhesive tape, which comprises peeling a body from the adhesive tape.
The pressure-sensitive adhesive layer has a peel strength with respect to a stainless steel plate after being immersed in a peeling liquid having an SP value of 22.0 or less for 30 seconds, which is 0.5 times or less than a peel strength with respect to the stainless steel plate before being immersed in the peeling liquid. Item 2. A method for peeling an adhesive tape according to Item 1.
The peeling method according to claim 1, wherein the peeling liquid has an SP value of 7.0 or more.
The stripping method according to claim 1, 2 or 3, wherein the stripping solution contains at least one selected from the group consisting of alcohol and ester.
Having a pressure-sensitive adhesive layer containing a styrene elastomer,
The pressure-sensitive adhesive layer has a peel strength with respect to a stainless steel plate after being immersed in a peeling liquid having an SP value of 22.0 or less for 30 seconds, which is 0.5 times or less than a peel strength with respect to the stainless steel plate before being immersed in the peeling liquid. tape.
An adhesive layer, a base material layer, and a second adhesive layer are laminated in this order,
The second adhesive layer has a peel strength with respect to a stainless steel plate after being immersed in a peeling liquid having an SP value of 22.0 or less for 30 seconds that is greater than 0.5 times the peel strength with respect to the stainless steel plate before being immersed in the peeling liquid. The adhesive tape according to claim 5.
The pressure-sensitive adhesive tape according to claim 5, wherein the pressure-sensitive adhesive layer has a peel strength of 5 N/25 mm or more with respect to stainless steel before being immersed in the peeling liquid having the SP value of 22.0 or less.
The pressure-sensitive adhesive tape according to claim 5, 6 or 7, wherein the pressure-sensitive adhesive layer has a peel strength of 3 N/25 m or less with respect to stainless steel after being immersed in the peeling liquid having the SP value of 22.0 or less.
The adhesive tape according to claim 5, 6, 7 or 8, wherein the styrene content of the styrene elastomer is 5% by weight or more and 40% by weight or less.
The pressure-sensitive adhesive tape according to claim 5, 6, 7, 8 or 9, wherein the styrene-based elastomer is a hydrogenated styrene-based elastomer.
The pressure-sensitive adhesive tape according to claim 5, 6, 7, 8, 9, or 10, wherein the styrene elastomer has a structure in which a spherical phase and another phase are phase-separated.
The pressure-sensitive adhesive tape according to claim 5, 6, 7, 8, 9, 10 or 11, wherein the pressure-sensitive adhesive layer contains a hydrogenated petroleum-based tacky fire.
The adhesive layer has a first surface and a second surface opposite to the first surface,
The adhesive tape according to claim 5, 6, 7, 8, 9, 10, 11, or 12, wherein the first surface has an embossed shape.
The adhesive tape according to claim 5, 6, 7, 8, 9, 10, 11, 12, or 13, wherein the embossed shape is formed by a plurality of grooves that are connected from one end to the other side surface of the pressure-sensitive adhesive layer. ..
The adhesive tape according to claim 6, 7, 8, 9, 10, 11, 12, 13 or 14, wherein the adhesive forming the second adhesive layer is an acrylic adhesive.
The pressure-sensitive adhesive tape according to claim 13 or 14, comprising a release film having protrusions corresponding to the embossed grooves on the first surface.
An electronic component comprising the adhesive tape according to claim 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 or 16.