Double-sided adhesive tape, article including the same, and disassembly method for article

Abstract

To provide a double-sided adhesive tape that achieves a sufficiently excellent balance between followability to an adherend and ease of peeling from the adherend.SOLUTION: A double-sided adhesive tape comprises, in this order, a first adhesive layer, a first resin layer, a foam substrate, a second resin layer and a second adhesive layer, the first resin layer containing a thermoplastic elastomer, and the double-sided adhesive tape having a 25% compression strength of 1 KPa or more and 12 KPa or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a double-sided pressure-sensitive adhesive tape, an article having the same, and a method for dismantling the article. [Background technology]

[0002] Double-sided pressure-sensitive adhesive tapes are widely used to fasten components constituting articles such as electronic devices. In particular, electronic devices and the like require thin double-sided pressure-sensitive adhesive tapes that are excellent in conformity with adherends and impact resistance. As such a double-sided pressure-sensitive adhesive tape, Patent Document 1 describes a double-sided pressure-sensitive adhesive tape having pressure-sensitive adhesive layers provided on both sides of a foam substrate and having a total thickness of 250 μm or less.

[0003] Furthermore, with the recent trend toward thinner and more sophisticated electronic devices, many thin, expensive parts made of rigid bodies are used as components for electronic devices, such as protective panels, image display modules, touch panels, and thin batteries that constitute image display units. It is desirable that such expensive parts be easily detachable from the main body (housing) of the electronic device, for example, when a malfunction occurs in the electronic device or when the electronic device is discarded, so that the main body of the electronic device and the removed parts can be reused. Therefore, double-sided pressure-sensitive adhesive tapes used to fix parts are required to be easily removable from the adherend during disassembly, in addition to being able to conform to the adherend.

[0004] As such a double-sided pressure-sensitive adhesive tape, Patent Document 2 discloses a double-sided pressure-sensitive adhesive tape in which resin films are laminated on both sides of a foam substrate and a pressure-sensitive adhesive layer is laminated on the surface of the resin film, and the foam substrate has a density of 0.45 g / cm 3The double-sided pressure-sensitive adhesive tape described below has a foam substrate with an interlaminar strength of 10 N / cm or more, and the pressure-sensitive adhesive layer is formed by providing a 25 μm thick pressure-sensitive adhesive layer on a 25 μm thick polyethylene terephthalate substrate, and the pressure-sensitive adhesive tape is pressed against an aluminum plate in an environment of 23°C temperature and 65% RH with a 2 kg roller in one back-and-forth press, and then left to stand for 1 hour in an environment of 23°C temperature and 50% RH relative humidity, and the pressure-sensitive adhesive layer has a 180° peel adhesion strength of 10 N / 20 mm or more at a peel speed of 300 mm / min.

[0005] However, conventional double-sided pressure-sensitive adhesive tapes have been insufficient in achieving both good conformability to the adherend and ease of peeling from the adherend. Therefore, a double-sided pressure-sensitive adhesive tape that satisfactorily satisfies both the ability to conform to an adherend and the ease of peeling from the adherend has not yet been provided, and there is a strong demand for such a tape to be provided promptly. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-155969 [Patent Document 2] International Publication No. 2015 / 098494 Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention aims to solve the above-mentioned problems of the prior art and to achieve the following object: In prior art double-sided pressure-sensitive adhesive tapes, conformability to an adherend and ease of releasability from an adherend are mutually contradictory properties (a trade-off relationship), making it difficult to achieve both, whereas the present invention aims to provide a double-sided pressure-sensitive adhesive tape or the like that satisfies both conformability to an adherend and ease of releasability from an adherend satisfactorily. [Means for solving the problem]

[0008] As a result of extensive research by the inventors to achieve the above-mentioned object, it was discovered that the present invention can provide a double-sided pressure-sensitive adhesive tape or the like that satisfies both excellent conformability to an adherend and ease of peeling from the adherend.

[0009] The present invention is based on the above findings by the present inventors, and the means for solving the above problems are as follows: <1> a first pressure-sensitive adhesive layer, a first resin layer, a foam substrate, a second resin layer, and a second pressure-sensitive adhesive layer, in this order; the first resin layer contains a thermoplastic elastomer, The double-sided pressure-sensitive adhesive tape is characterized in that the 25% compressive strength of the double-sided pressure-sensitive adhesive tape is 1 KPa or more and 12 KPa or less. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a double-sided pressure-sensitive adhesive tape or the like that satisfies both excellent conformability to an adherend and ease of peeling from the adherend. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic cross-sectional view showing an example of the double-sided pressure-sensitive adhesive tape of the present invention. [Figure 2A] FIG. 2A is a schematic diagram (part 1) showing an example of a method for dismantling an article according to the present invention. [Figure 2B] FIG. 2B is a schematic diagram (part 2) showing an example of the method for dismantling an article according to the present invention. [Figure 2C] FIG. 2C is a schematic diagram (part 2) showing an example of the method for dismantling an article according to the present invention. [Figure 3] FIG. 3 is a diagram for explaining a method for evaluating tracking ability. [Figure 4] FIG. 4 is a micrograph of the area between the double-sided adhesive tape and the edge of the step in the evaluation of conformability. DETAILED DESCRIPTION OF THE INVENTION

[0012] (double-sided adhesive tape) The double-sided pressure-sensitive adhesive tape of the present disclosure has, in this order, a first pressure-sensitive adhesive layer, a first resin layer, a foam substrate, a second resin layer, and a second pressure-sensitive adhesive layer.

[0013] Fig. 1 is a schematic cross-sectional view showing an example of a double-sided pressure-sensitive adhesive tape of the present embodiment. In the double-sided pressure-sensitive adhesive tape 10 of the present embodiment shown in Fig. 1, a first resin layer 2 and a second resin layer 4 are provided on both sides of a foam substrate 3, respectively, and a first pressure-sensitive adhesive layer 1 and a second pressure-sensitive adhesive layer 5 are provided on the surfaces of the first resin layer 2 and the second resin layer 4 opposite the foam substrate 3, respectively. The first resin layer 2 and the second resin layer 4 may be provided in direct contact with both surfaces of the foam substrate 3. The resin layers being provided in direct contact with the surfaces of the foam substrate means that the foam substrate and the resin layers are in contact with each other, with no other layer, such as a pressure-sensitive adhesive layer, interposed between the foam substrate and each resin layer.

[0014] <First resin layer> The first resin layer is provided on one surface of the foam substrate, which is one of two main surfaces opposing each other in the thickness direction of the double-sided pressure-sensitive adhesive tape of this embodiment.

[0015] The first resin layer contains a thermoplastic elastomer, and may further contain other components. The first resin layer preferably contains a thermoplastic elastomer as a main component of the first resin layer. The main component of the first resin layer refers to the component that is contained in the largest amount in the first resin layer, excluding the solvent and the like.

[0016] -Thermoplastic elastomer- The thermoplastic elastomer is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include polyurethane thermoplastic elastomers (TPU), polyester thermoplastic elastomers (TPEE, TPC), polyamide thermoplastic elastomers (TPAE, TPA), polyolefin thermoplastic elastomers (TPO), polystyrene thermoplastic elastomers (SBC, TPS), vinyl chloride thermoplastic elastomers (TPVC), etc. These may be used alone or in combination of two or more. Among these, polyurethane-based thermoplastic elastomers (TPU) are preferred because they can be easily conformed to the adherend and easily peeled from the adherend.

[0017] The polyurethane-based thermoplastic elastomer is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include ester-type polyurethane-based thermoplastic elastomers and ether-type polyurethane-based thermoplastic elastomers.

[0018] The ester-type polyurethane thermoplastic elastomer can be produced using an ester-type polyol such as polyethylene adipate (PEA), polybutylene adipate (PBA), polyhexamethylene adipate (PHA), poly(3-methylpentane adipate) (PMPA), or polycaprolactone (PCL).

[0019] The ether-type polyurethane thermoplastic elastomer can be produced using an ether-type polyol such as polyethylene glycol (PEG), polypropylene glycol (PPG), or polytetramethylene ether glycol (PTMG).

[0020] The amount of thermoplastic elastomer in the first resin layer is not particularly limited and can be selected appropriately depending on the purpose, but is preferably 60% by mass or more and 100% by mass or less, and more preferably 80% by mass or more and 100% by mass or less.

[0021] -Other ingredients- The other components are not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include tackifying resins such as phenolic tackifying resins, terpene tackifying resins, rosin tackifying resins, petroleum resins, styrene resins, coumarone-indene resins, and ketone resins; crosslinking reaction accelerators; inorganic fillers such as silica, alumina, aluminum flakes, and glass flakes; coupling agents; antioxidants; heat stabilizers; ultraviolet absorbers; hydrolysis inhibitors; plasticizers; antistatic agents; lubricants; antiblocking agents; colorants; organic fillers; and nucleating agents.

[0022] The thickness of the first resin layer is not particularly limited and can be selected appropriately depending on the purpose, but in order to achieve both conformability to the adherend and ease of peeling from the adherend, it is more preferably 10 μm or more and 30 μm or less, particularly preferably 12 μm or more and 28 μm or less, and most preferably 15 μm or more and 25 μm or less.

[0023] The lower limit of the tensile breaking strength of the first resin layer is not particularly limited and can be appropriately selected depending on the purpose. However, from the viewpoint of achieving both conformability to the adherend and ease of peeling from the adherend, the lower limit is preferably 1 MPa or more, more preferably 10 MPa or more, and even more preferably 15 MPa or more. Preferred. The upper limit of the tensile breaking strength of the first resin layer is not particularly limited and can be selected appropriately depending on the purpose, but in order to achieve both conformability to the adherend and ease of peeling from the adherend, it is preferably 56 MPa or less, more preferably 45 MPa or less, and even more preferably 40 MPa or less. It is preferable that the numerical range has a lower limit value and an upper limit value that are either of the numerical values ​​shown as the lower limit value and either of the numerical values ​​shown as the upper limit value. Among these, in order to achieve both conformability to the adherend and ease of peeling from the adherend, the tensile breaking strength of the first resin layer is preferably 1 MPa or more and 56 MPa or less, more preferably 10 MPa or more and 45 MPa or less, and even more preferably 15 MPa or more and 40 MPa or less.

[0024] The tensile breaking strength of the first resin layer is determined in accordance with JIS K 6767:1990 by cutting a piece of the first resin layer into a 1 cm width with a 2 cm gauge interval, and pulling it at a pulling speed of 300 mm / min using a tensile testing machine (Tensilon universal material testing machine, model: RTF-1210, manufactured by A&D Co., Ltd.) under conditions of a temperature of 23°C and a relative humidity of 50%, and the stress per unit area (maximum stress) at which the first resin layer breaks.

[0025] The lower limit of the tensile modulus of the first resin layer is not particularly limited and can be selected appropriately depending on the purpose, but in order to achieve both conformability to the adherend and ease of peeling from the adherend, it is preferably 10 MPa or more, more preferably 15 MPa or more, and even more preferably 20 MPa or more. The upper limit of the tensile modulus of the first resin layer is not particularly limited and can be selected appropriately depending on the purpose, but in order to achieve both conformability to the adherend and ease of peeling from the adherend, it is preferably 56 MPa or less, more preferably 50 MPa or less, and even more preferably 40 MPa or less. It is preferable that the numerical range has a lower limit value and an upper limit value that are either of the numerical values ​​shown as the lower limit value and either of the numerical values ​​shown as the upper limit value. Among these, in order to achieve both conformability to the adherend and ease of peeling from the adherend, the tensile modulus of the first resin layer is preferably 10 MPa or more and 56 MPa or less, more preferably 15 MPa or more and 50 MPa or less, and most preferably 20 MPa or more and 40 MPa or less.

[0026] The tensile modulus of the first resin layer is determined in accordance with JIS K 6767:1990 by pulling a piece of the first resin layer cut to a width of 1 cm with a gauge interval of 2 cm at a temperature of 23°C and a relative humidity of 50% at a pulling speed of 300 mm / min using a tensile testing machine (Tensilon universal testing machine, model: RTF-1210, manufactured by A&D Co., Ltd.), and the slope of the tensile strength (the slope of the rising edge of the stress-strain curve) in the elongation range of 1% or more and 3% or less.

[0027] The lower limit of the tensile elongation at break of the first resin layer is not particularly limited and can be selected appropriately depending on the purpose, but in order to achieve both conformability to the adherend and ease of peeling from the adherend, it is preferably 200% or more, particularly preferably 250% or more, and even more preferably 270% or more. The upper limit of the tensile elongation at break of the first resin layer is not particularly limited and can be selected appropriately depending on the purpose, but in order to achieve both conformability to the adherend and ease of peeling from the adherend, it is preferably 1000% or less, more preferably 500% or less, and even more preferably 380% or less. It is preferable that the numerical range has a lower limit value and an upper limit value that are either of the numerical values ​​shown as the lower limit value and either of the numerical values ​​shown as the upper limit value. Among these, the tensile elongation at break of the first resin layer is preferably 200% or more and 1000% or less, more preferably 250% or more and 500% or less, and even more preferably 270% or more and 380% or less. Preferred.

[0028] The tensile breaking elongation of the first resin layer is determined in accordance with JIS K 6767:1990 by pulling a piece of the first resin layer cut to a width of 1 cm with a gauge interval of 2 cm at a temperature of 23°C and a relative humidity of 50% at a pulling speed of 300 mm / min using a tensile testing machine (Tensilon universal material testing machine, model: RTF-1210, manufactured by A&D Co., Ltd.), and the elongation at break of the first resin layer is defined as the elongation at which the first resin layer breaks.

[0029] <Second resin layer> The second resin layer is provided on the other surface of the foam substrate, which is different from the surface on which the first resin layer is provided. The other surface of the foam substrate is one of two main surfaces that face each other in the thickness direction of the double-sided pressure-sensitive adhesive tape of this embodiment.

[0030] The second resin layer is not particularly limited and can be appropriately selected depending on the purpose, but is preferably one containing a polyester resin. The second resin layer may further contain other components. The second resin layer preferably contains a polyester resin as a main component of the second resin layer. The main component of the second resin layer refers to the component that is contained in the largest amount in the second resin layer, excluding the solvent and the like.

[0031] The polyester resin is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), polybutylene naphthalate (PBN), etc. These may be used alone or in combination of two or more. Among these, polyethylene terephthalate (PET) is preferred from the viewpoint of achieving both good conformability to the adherend and ease of peeling from the adherend.

[0032] The amount of polyester resin in the second resin layer is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 60% by mass or more and 100% by mass or less, and more preferably 80% by mass or more and 100% by mass or less.

[0033] Other components in the second resin layer are the same as those described in "-Other components-" in "<First resin layer>" above.

[0034] The second resin layer is not particularly limited and can be appropriately selected depending on the purpose, but is preferably different from the first resin layer. The second resin layer and the first resin layer may be different in material (composition), physical properties, or both.

[0035] The thickness of the second resin layer is not particularly limited and can be selected appropriately depending on the purpose, but in order to achieve both conformability to the adherend and ease of peeling from the adherend, the thickness is preferably 1 μm or more and 100 μm or less, more preferably 15 μm or more and 80 μm or less, even more preferably 25 μm or more and 75 μm or less, and particularly preferably 45 μm or more and 55 μm or less.

[0036] The tensile breaking strength of the second resin layer is not particularly limited and can be selected appropriately depending on the purpose. However, it is preferable that the tensile breaking strength of the second resin layer be higher than that of the first resin layer in terms of achieving both good conformability to the adherend and ease of peeling from the adherend, as well as ease of processing when the double-sided pressure-sensitive adhesive tape is processed into a desired shape by punching or the like, and suppression of deformation during processing. The tensile strength at break of the second resin layer is determined in the same manner as the tensile strength at break of the first resin layer. Measure.

[0037] The lower limit of the tensile breaking strength of the second resin layer is not particularly limited and can be selected appropriately depending on the purpose, but from the viewpoint of achieving both ease of punching and ease of peeling from the adherend, it is preferably 100 MPa or more, more preferably 150 MPa or more, and even more preferably 200 MPa or more. The upper limit of the tensile breaking strength of the second resin layer is not particularly limited and can be selected appropriately depending on the purpose, but in order to achieve both ease of punching and ease of peeling from the adherend, it is preferably 500 MPa or less, more preferably 400 MPa or less, and even more preferably less than 300 MPa. It is preferable that the numerical range has a lower limit value and an upper limit value that are either of the numerical values ​​shown as the lower limit value and either of the numerical values ​​shown as the upper limit value. Among these, in order to achieve both ease of punching and ease of peeling from the adherend, the tensile breaking strength of the second resin layer is preferably 100 MPa or more and 500 MPa or less, more preferably 150 MPa or more and 400 MPa or less, even more preferably 200 MPa or more and less than 300 MPa, particularly preferably 220 MPa or more and 280 MPa or less, and most preferably 240 MPa or more and 260 MPa or less.

[0038] The tensile breaking strength of the second resin layer is measured in the same manner as the tensile breaking strength of the first resin layer.

[0039] The lower limit of the tensile modulus of the second resin layer is not particularly limited and can be selected appropriately depending on the purpose. However, in order to achieve both ease of punching and ease of peeling from the adherend, the lower limit is preferably 100 MPa or more, more preferably 1000 MPa or more, and even more preferably 2000 MPa or more. The upper limit of the tensile modulus of the second resin layer is not particularly limited and can be selected appropriately depending on the purpose, but from the viewpoint of achieving both ease of punching and ease of peeling from the adherend, it is preferably 10,000 MPa or less, more preferably 8,000 MPa or less, and even more preferably 5,000 MPa or less. It is preferable that the numerical range has a lower limit value and an upper limit value that are either of the numerical values ​​shown as the lower limit value and either of the numerical values ​​shown as the upper limit value. Among these, in order to achieve both ease of punching and ease of peeling from the adherend, the tensile modulus of the second resin layer is preferably 100 MPa or more and 10,000 MPa or less, more preferably 1,000 MPa or more and 8,000 MPa or less, and even more preferably 2,000 MPa or more and 5,000 MPa or less.

[0040] The tensile modulus of elasticity of the second resin layer is measured in the same manner as the tensile modulus of elasticity of the first resin layer.

[0041] The lower limit of the tensile elongation at break of the second resin layer is not particularly limited and can be selected appropriately depending on the purpose, but from the viewpoint of achieving both ease of punching and ease of peeling from the adherend, it is preferably 1% or more, more preferably 5% or more, and even more preferably 10% or more. The upper limit of the tensile elongation at break of the second resin layer is not particularly limited and can be selected appropriately depending on the purpose, but in order to achieve both conformability to the adherend and ease of peeling from the adherend, it is preferably 100% or less, more preferably 50% or less, and even more preferably 30% or less. It is preferable that the numerical range has a lower limit value and an upper limit value that are either of the numerical values ​​shown as the lower limit value and either of the numerical values ​​shown as the upper limit value. Among these, the tensile elongation at break of the second resin layer is preferably 1% or more and 100% or less, more preferably 5% or more and 50% or less, and even more preferably 5% or more and 20% or less.

[0042] The tensile elongation at break of the second resin layer is measured in the same manner as the tensile elongation at break of the first resin layer.

[0043] <Foam base material> The foam substrate is provided between the first resin layer and the second resin layer. The foam substrate can support the first resin layer, the second resin layer, and the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer.

[0044] The foam base material is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include polyurethane foams made of polyurethane resins, polyolefin foams made of polyolefin resins, acrylic foams made of acrylic resins, and rubber foams made of rubber resins such as acrylic rubber or other elastomers. Among these, polyurethane foams are preferred because they can conform to the adherend and be easily peeled off from the adherend. The surface of the foam substrate may be subjected to antistatic treatment, corona treatment, or the like.

[0045] In addition to the resins described above, the foam substrate may contain, as necessary, additives such as plasticizers, antioxidants, foaming aids such as zinc oxide, bubble nuclei adjusters, heat stabilizers, flame retardants such as aluminum hydroxide and magnesium hydroxide, antistatic agents, hollow balloon beads made of glass or plastic, fillers such as metal powders and metal compounds, conductive fillers, and thermally conductive fillers.

[0046] The thickness of the foam substrate is not particularly limited and can be selected appropriately depending on the purpose. However, in order to achieve both good conformability to the adherend and ease of peeling from the adherend, the thickness is preferably 500 μm or more and 2000 μm or less, more preferably 550 μm or more and 1700 μm or less, and even more preferably 600 μm or more and 1500 μm or less.

[0047] The lower limit of the bulk density of the foam substrate is not particularly limited and can be appropriately selected depending on the purpose. However, from the viewpoint of achieving both conformability to the adherend and ease of peeling from the adherend, it is preferred that the lower limit be 10 kg / m 3 More than 50 kg / m is preferable. 3 More preferably, 100 kg / m 3 More preferably, 130 kg / m 3 More than 140 kg / m is particularly preferred. 3 The above is most preferable. The upper limit of the bulk density of the foam substrate is not particularly limited and can be appropriately selected depending on the purpose. However, from the viewpoint of achieving both conformability to the adherend and ease of peeling from the adherend, and from the viewpoint of being less likely to fall when attached to an inclined surface and having excellent tilt durability (excellent tilt retention), it is preferable to use a bulk density of 1000 kg / m 3 Preferably less than 500 kg / m 3 Less than 250 kg / m is more preferable. 3 More preferably, 200 kg / m 3 The following is particularly preferred: 180 kg / m 3 The following are most preferred: It is preferable that the numerical range has a lower limit value and an upper limit value that are either of the numerical values ​​shown as the lower limit value and either of the numerical values ​​shown as the upper limit value. Among these, 10kg / m is the best choice because it is easy to follow the adherend and peels off easily from the adherend, and it is hard to fall off when applied to an inclined surface and has excellent tilt durability (excellent tilt retention). 3 More than 1000kg / m 3 Less than 50 kg / m 3 More than 500kg / m 3 Less than 100 kg / m is more preferable. 3 More than 250kg / m 3More preferably, 130 kg / m 3 More than 200kg / m 3 Particularly preferred is 140 kg / m 3 More than 180kg / m 3 The following are most preferred:

[0048] The bulk density of the foam substrate is measured in accordance with JIS K 6767:1990 using a 100 mm x 100 mm The foam base material cut into 100 mm pieces is weighed using a 0.1 mg electronic balance, and the weight is divided by the volume of the cut foam base material to obtain the value.

[0049] The thickness of the foam substrate, the first resin layer, and the second resin layer (the total thickness of the foam laminate sheet consisting of three layers: the first resin layer, the foam substrate, and the second resin layer) is not particularly limited and can be selected appropriately depending on the purpose, but in order to achieve both conformability to the adherend and ease of peeling from the adherend, it is preferably 500 μm or more and 2000 μm or less, more preferably 600 μm or more and 1800 μm or less, and even more preferably 650 μm or more and 1550 μm or less.

[0050] The lower limit of the 25% compressive strength of the foam substrate, the first resin layer, and the second resin layer (the 25% compressive strength of a foam laminate sheet consisting of three layers: the first resin layer, the foam substrate, and the second resin layer) is not particularly limited and can be selected appropriately depending on the purpose, but from the viewpoint of achieving both conformability to the adherend and ease of peeling from the adherend, it is preferably 1 KPa or more, more preferably 2 KPa or more, and even more preferably 3 KPa or more. There is no particular upper limit to the 25% compressive strength of the foam substrate, the first resin layer, and the second resin layer (the 25% compressive strength of a foam laminate sheet consisting of three layers: the first resin layer, the foam substrate, and the second resin layer), and it can be selected appropriately depending on the purpose.However, in order to achieve both conformability to the adherend and ease of peeling from the adherend, it is preferably 12 KPa or less, more preferably 8 KPa or less, and even more preferably 5 KPa or less. It is preferable that the numerical range has a lower limit value and an upper limit value that are either of the numerical values ​​shown as the lower limit value and either of the numerical values ​​shown as the upper limit value. Among these, in order to achieve both conformability to the adherend and ease of peeling from the adherend, the 25% compressive strength of the foam substrate, the first resin layer, and the second resin layer (the 25% compressive strength of a foam laminate sheet consisting of three layers: the first resin layer, the foam substrate, and the second resin layer) is preferably 1 KPa or more and 12 KPa or less, more preferably 2 KPa or more and 8 KPa or less, and even more preferably 3 KPa or more and 5 KPa or less.

[0051] The 25% compression strength of the foam substrate, the first resin layer, and the second resin layer (the 25% compression strength of a foam laminate sheet consisting of three layers: a first resin layer, a foam substrate, and a second resin layer) is determined in accordance with JIS K 6767:1990 by placing a foam substrate cut to 25 mm x 25 mm on a stainless steel plate larger than the foam substrate with the second resin layer side facing the stainless steel plate, and pressing the foam substrate with a probe (D = 7 mm) at a rate of 0.5 mm / min under conditions of a temperature of 23°C and a relative humidity of 50% to compress the sheet by 25% of its total thickness.

[0052] The lower limit of the 25% compressive strength per unit thickness (25% compressive strength / thickness) of the foam laminate sheet consisting of three layers of the first resin layer, the foam base material, and the second resin layer is not particularly limited and can be appropriately selected depending on the purpose. However, from the viewpoint of achieving both conformability to the adherend and ease of peeling from the adherend, it is preferable that the lower limit be 1×10 -3 (KPa / μm) or more is preferable, and 2×10 -3 (KPa / μm) or more is more preferable, and 2.5×10 -3 (KPa / μm) or more is more preferable. The upper limit of the 25% compressive strength per unit thickness (25% compressive strength / thickness) of the foam laminate sheet consisting of three layers of the first resin layer, the foam base material, and the second resin layer is not particularly limited and can be appropriately selected depending on the purpose. However, from the viewpoint of achieving both conformability to the adherend and ease of peeling from the adherend, it is preferable to set the upper limit to 20×10 -3 (KPa / μm) or less is preferable, and 16×10-3 (KPa / μm) or less is more preferable, and 8×10 -3 (KPa / μm) or less is more preferable, and 7×10 -3 (KPa / μm) or less is particularly preferable, and 6×10 -3 (KPa / μm) or less is most preferable. Among these, the above-mentioned adhesive is preferred because it is easy to both conform to the adherend and peel from the adherend. The foam laminate sheet consisting of the three layers of the first resin layer, the foam base material, and the second resin layer has a 25% compressive strength per unit thickness (25% compressive strength / thickness) of 1×10 -3 (KPa / μm) or more 20×10 -3 (KPa / μm) or less is preferable, and 1×10 -3 (KPa / μm) or more 16×10 -3 (KPa / μm) or less is more preferable, and 2×10 -3 (KPa / μm) or more 8×10 -3 (KPa / μm) or less is more preferable, and 2×10 -3 (KPa / μm) or more 7×10 -3 (KPa / μm) or less is particularly preferable, and 2.5 × 10 -3 (KPa / μm) or more than 6×10 -3 (KPa / μm) or less is most preferable.

[0053] The peel strength (Method 31B) of the surface of the first resin layer facing the first pressure-sensitive adhesive layer is preferably 1 N / 25 mm or more and 10 N / 25 mm or less, more preferably 2 N / 25 mm or more and 8 N / 25 mm or less, even more preferably 3 N / 25 mm or more and 6 N / 25 mm or less, particularly preferably 4 N / 25 mm or more and 6 N / 25 mm or less, and most preferably 5 N / 25 mm or more and 6 N / 25 mm or less, in order to achieve both good conformability to the adherend and ease of peeling from the adherend, increase the adhesion of the first resin layer to the first pressure-sensitive adhesive layer, and prevent the first resin layer from peeling from the foam substrate and the first pressure-sensitive adhesive layer.

[0054] The peel strength (31B method) of the surface of the first resin layer facing the first adhesive layer was determined by bonding the second resin layer side of a foam laminate sheet (" / " indicates the lamination interface) consisting of a first resin layer / foam substrate / second resin layer to a stainless steel (SUS) plate using a strong adhesive double-sided tape (manufactured by DIC Corporation, product name #8800CH), bonding a single-sided adhesive tape (manufactured by Nitto Denko Corporation, polyester adhesive tape No. 31B) to the first resin layer side of the laminate, applying pressure once back and forth with a 2 kg roll, leaving it to stand for 1 hour, and then peeling the single-sided adhesive tape in a 180° direction at a speed of 300 mm / min.

[0055] The polyurethane foam may be a commercially available product, such as the SU-SS series (manufactured by ShengYing New Material Technology (Changzhou) Co., Ltd.), the SU-S series (manufactured by ShengYing New Material Technology (Changzhou) Co., Ltd.), or the SR-X2-15CTP series (manufactured by Inoac Corporation).

[0056] <First adhesive layer> The first pressure-sensitive adhesive layer is provided on the surface of the first resin layer opposite to the foam substrate. The first pressure-sensitive adhesive layer may be provided on the surface of the first resin layer opposite to the foam substrate, in direct contact with the surface, or may be provided with another layer interposed therebetween.

[0057] The first adhesive layer contains an adhesive, and may further contain other components.

[0058] The pressure-sensitive adhesive is not particularly limited and can be appropriately selected depending on the purpose. For example, known pressure-sensitive adhesives such as acrylic pressure-sensitive adhesives, rubber pressure-sensitive adhesives, silicone pressure-sensitive adhesives, urethane pressure-sensitive adhesives, polyester pressure-sensitive adhesives, styrene-diene block copolymer pressure-sensitive adhesives, vinyl alkyl ether pressure-sensitive adhesives, polyamide pressure-sensitive adhesives, fluorine-based pressure-sensitive adhesives, creep property-improved pressure-sensitive adhesives, and radiation-curable pressure-sensitive adhesives can be used. Among these, acrylic adhesives are preferred because of their excellent adhesive reliability.

[0059] The acrylic adhesive includes those containing an acrylic polymer. Examples of the acrylic polymer include those obtained by polymerizing a monomer component containing a (meth)acrylic monomer such as a (meth)acrylic acid alkyl ester.

[0060] Examples of the (meth)acrylic acid alkyl ester include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, s-butyl (meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and methyl (meth)acrylate. Examples of the alkyl (meth)acrylate include isooctyl (meth)acrylate, nonyl (meth)acrylate, isononyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, tridecyl (meth)acrylate, tetradecyl (meth)acrylate, pentadecyl (meth)acrylate, hexadecyl (meth)acrylate, heptadecyl (meth)acrylate, octadecyl (meth)acrylate, nonadecyl (meth)acrylate, and eicosyl (meth)acrylate. The alkyl (meth)acrylates may be used alone or in combination of two or more. Among these, the (meth)acrylic acid alkyl ester is preferably a (meth)acrylic acid alkyl ester in which the alkyl group has 1 to 20 carbon atoms, more preferably a (meth)acrylic acid alkyl ester in which the alkyl group has 4 to 18 carbon atoms, and even more preferably a (meth)acrylic acid alkyl ester in which the alkyl group has 4 to 9 carbon atoms. Examples of the alkyl group include linear and branched alkyl groups. In this specification, the term "(meth)acrylic acid alkyl ester" means an acrylic acid alkyl ester or a methacrylic acid alkyl ester.

[0061] Among these, butyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isononyl (meth)acrylate, and ethyl (meth)acrylate are preferred as the (meth)acrylic acid alkyl esters because they can easily ensure suitable adhesive strength.

[0062] The (meth)acrylic acid alkyl ester is preferably used in a range of 90% by mass or more and 99% by mass or less relative to the total amount of the (meth)acrylic monomer, and more preferably in a range of 90% by mass or more and 96% by mass or less, since this makes it easier to ensure suitable adhesive strength.

[0063] The (meth)acrylic monomer may be a monomer having a polar group such as a hydroxyl group, a carboxyl group, or an amide group, in addition to a (meth)acrylic acid alkyl ester. Specifically, monomers having a carboxyl group, such as (meth)acrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, and isocrotonic acid, or anhydrides thereof; monomers having a sulfonic acid group, such as sodium vinyl sulfonate; monomers having a cyano group, such as acrylonitrile; monomers having an amide group, such as acrylamide, methacrylamide, N-vinylpyrrolidone, and N,N-dimethyl(meth)acrylamide; monomers having a hydroxyl group, such as hydroxyalkyl (meth)acrylate and glycerin dimethacrylate; monomers having an amino group, such as aminoethyl (meth)acrylate and (meth)acryloylmorpholine; and monomers having an imide group, such as cyclohexylmaleimide and isopropylmaleimide. monomers having an epoxy group such as glycidyl (meth)acrylate and methyl glycidyl (meth)acrylate; monomers having an isocyanate group such as 2-methacryloyloxyethyl isocyanate; and monomers such as triethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, ethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and divinylbenzene. These may be used alone or in combination of two or more.

[0064] As the monomer, in addition to (meth)acrylic monomers, aromatic vinyl compounds such as styrene and substituted styrene; olefins such as ethylene, propylene, and butadiene; vinyl esters such as vinyl acetate; vinyl chloride, etc. can also be used.

[0065] The acrylic polymer can be produced by polymerizing a monomer by a method such as solution polymerization, bulk polymerization, suspension polymerization, or emulsion polymerization. However, the solution polymerization method is preferred in terms of improving the production efficiency of the acrylic polymer.

[0066] The solution polymerization method is not particularly limited and can be appropriately selected depending on the purpose. For example, a method in which a monomer, a polymerization initiator, and an organic solvent are mixed and stirred preferably at a temperature of 40°C or higher and 90°C or lower to cause radical polymerization can be mentioned.

[0067] The polymerization initiator is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include peroxides such as benzoyl peroxide and lauryl peroxide, azo-based thermal polymerization initiators such as azobisisobutylnitrile, acetophenone-based photopolymerization initiators, benzoin ether-based photopolymerization initiators, benzyl ketal-based photopolymerization initiators, acylphosphine oxide-based photopolymerization initiators, benzoin-based photopolymerization initiators, and benzophenone-based photopolymerization initiators. The acrylic polymer obtained by the above method may be in a state of being dissolved or dispersed in an organic solvent, for example, when it is produced by a solution polymerization method.

[0068] The acrylic polymer obtained by the above method preferably has a weight average molecular weight of 300,000 or more and 1,200,000 or less, more preferably 400,000 or more and 1,100,000 or less, and even more preferably 500,000 or more and 1,000,000 or less, in order to provide excellent adhesive strength even in a thin layer and good conformability to unevenness.

[0069] The weight-average molecular weight is a value measured by gel permeation chromatography (GPC) and calculated in terms of standard polystyrene. Specifically, the weight-average molecular weight is measured using a GPC apparatus (HLC-8329GPC) manufactured by Tosoh Corporation under the following conditions: Sample concentration: 0.5% by mass (tetrahydrofuran solution) Sample injection volume: 100 μL Eluent: tetrahydrofuran Flow rate: 1.0mL / min Measurement temperature: 40℃ Main column: TSKgel GMHHR-H(20) x 2 Guard column: TSKgel HXL-H Detector: differential refractometer Weight average molecular weight of standard polystyrene: 10,000 to 20 million (manufactured by Tosoh Corporation)

[0070] The adhesive used to form the adhesive layer preferably contains a tackifier resin, in order to form an adhesive layer with even better adhesive strength and conformability. The tackifying resin is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include rosin-based tackifying resins, polymerized rosin-based tackifying resins, polymerized rosin ester-based tackifying resins, rosin phenol-based tackifying resins, stabilized rosin ester-based tackifying resins, disproportionated rosin ester-based tackifying resins, hydrogenated rosin ester-based tackifying resins, terpene-based tackifying resins, terpene phenol-based tackifying resins, and petroleum resin-based tackifying resins such as styrene-based tackifying resins.

[0071] The tackifier resin has excellent adhesive strength even in a thin layer and good conformability to unevenness. From this viewpoint, it is preferable to use a combination of a rosin-based tackifying resin and a petroleum resin-based tackifying resin. The rosin-based tackifying resin and petroleum resin-based tackifying resin are preferably used in combination with the acrylic polymer, particularly in order to obtain even a thin layer with superior adhesive strength, and are more preferably used in combination with an acrylic polymer obtained by polymerizing a monomer containing butyl (meth)acrylate.

[0072] As the tackifier resin, it is preferable to use a tackifier resin that is liquid at room temperature, in order to further improve the initial adhesive strength of the pressure-sensitive adhesive layer. The tackifying resin that is liquid at room temperature is not particularly limited and can be selected appropriately depending on the purpose. Examples include process oil, polyester plasticizers, low molecular weight liquid rubbers such as polybutene, and terpene phenol resins. Commercially available products include YP-90L manufactured by Yasuhara Chemical Co., Ltd.

[0073] In order to provide even better adhesive strength, the tackifier resin is preferably used in an amount of 20 parts by mass or more and 60 parts by mass or less, and more preferably 30 parts by mass or more and 55 parts by mass or less, relative to 100 parts by mass of the acrylic polymer.

[0074] The adhesive constituting the adhesive layer may contain, in addition to the acrylic polymer, a softener, a plasticizer, a filler, an antioxidant, a colorant, etc., as required. Among the above-mentioned pressure-sensitive adhesives, it is preferable to use a crosslinking agent, since this makes it easier to maintain the shape of the pressure-sensitive adhesive layer, making it easier to prevent changes over time, and the pressure-sensitive adhesive layer has excellent adhesive strength and good conformability to unevenness.

[0075] The crosslinking agent is not particularly limited and can be appropriately selected depending on the purpose. For example, an isocyanate crosslinking agent or an epoxy crosslinking agent is preferred. The isocyanate crosslinking agent is not particularly limited and can be appropriately selected depending on the purpose. For example, tolylene diisocyanate, naphthylene-1,5-diisocyanate, hexamethylene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, trimethylolpropane-modified tolylene diisocyanate, etc. can be used, and toluene diisocyanate adducts such as tolylene diisocyanate and trimethylolpropane-modified tolylene diisocyanate are preferred. The toluene diisocyanate adduct has a structure derived from toluene diisocyanate in the molecule, and a commercially available product thereof is, for example, Coronate L (manufactured by Nippon Polyurethane Industry Co., Ltd.).

[0076] When the isocyanate crosslinking agent is used, it is preferable to use an acrylic polymer having a hydroxyl group as the acrylic polymer. The acrylic polymer having a hydroxyl group can be produced using, as a monomer, for example, 2-hydroxyethyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, etc., and among these, it is more preferable to use 2-hydroxyethyl (meth)acrylate and 4-hydroxybutyl (meth)acrylate.

[0077] The epoxy crosslinking agent is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include Tetrad X and Tetrad C manufactured by Mitsubishi Gas Chemical Co., Ltd., and E-05X manufactured by Soken Chemical Co., Ltd.

[0078] When the epoxy crosslinking agent is used, the acrylic polymer is an acrylic polymer having an acid group. It is preferred to use a vinyl polymer. The acrylic polymer having an acid group is preferably produced using, as a monomer, for example, (meth)acrylic acid, acrylic acid dimer, itaconic acid, crotonic acid, maleic acid, maleic anhydride, or the like, and more preferably (meth)acrylic acid.

[0079] In order to increase the holding strength on the inclined surface and suppress peeling, the crosslinking agent is preferably used in a range such that the gel fraction of the pressure-sensitive adhesive layer formed is 25% by mass or more and 95% by mass or less, more preferably 30% by mass or more and 90% by mass or less, even more preferably 35% by mass or more and 85% by mass or less, particularly preferably 40% by mass or more and 80% by mass or less, and most preferably 45% by mass or more and 75% by mass or less. The gel fraction is determined by immersing the pressure-sensitive adhesive layer after aging in toluene, leaving it for 24 hours, measuring the mass of the remaining insoluble matter after drying, and expressing it as a percentage of the original mass.

[0080] The thickness of the first pressure-sensitive adhesive layer is not particularly limited and can be selected appropriately depending on the purpose, but in order to achieve both good conformability to the adherend and ease of peeling from the adherend, the thickness is preferably 65 μm or more and 100 μm or less, more preferably 70 μm or more and 95 μm or less, and even more preferably 75 μm or more and 90 μm or less.

[0081] <Second adhesive layer> The second pressure-sensitive adhesive layer is provided on the surface of the second resin layer opposite to the foam substrate. The second pressure-sensitive adhesive layer may be provided on the surface of the second resin layer opposite to the foam substrate, in direct contact with the surface, or may be provided with another layer interposed therebetween.

[0082] The second adhesive layer contains an adhesive, and may further contain other components. The adhesive is the same as the adhesive described above (first adhesive layer).

[0083] The second pressure-sensitive adhesive layer is not particularly limited and can be appropriately selected depending on the purpose, but it is preferably made of the same material (composition) as the first pressure-sensitive adhesive layer.

[0084] The thickness of the second pressure-sensitive adhesive layer is not particularly limited and can be appropriately selected depending on the purpose, but from the viewpoint of achieving both good conformability to the adherend and ease of peeling from the adherend, it is preferably 65 μm to 100 μm, more preferably 70 μm to 95 μm, and even more preferably 75 μm to 90 μm. The thickness of the second pressure-sensitive adhesive layer may be the same as or different from the thickness of the first pressure-sensitive adhesive layer. In other words, the thickness of the first pressure-sensitive adhesive layer and the thickness of the second pressure-sensitive adhesive layer can each be set within a preferred range independently.

[0085] <Other layers> The double-sided pressure-sensitive adhesive tape of the present disclosure may further include other layers in addition to the foam substrate, first and second pressure-sensitive adhesive layers, and first and second resin layers. The other layers are not particularly limited and can be selected appropriately depending on the purpose, and examples thereof include a light-shielding layer, a light-reflecting layer, a conductive layer, a heat-conductive layer, and an electromagnetic wave shielding layer. The location of the other layers in the double-sided pressure-sensitive adhesive tape is not particularly limited and can be selected appropriately depending on the purpose, and examples thereof include a location between the first resin layer and the first pressure-sensitive adhesive layer, or between the second resin layer and the second pressure-sensitive adhesive layer.

[0086] The double-sided pressure-sensitive adhesive tape of the present disclosure may have a release liner on the surface of each of the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer opposite to the foam substrate side. Any known material can be used, for example, a resin film whose surface is coated with a release agent, etc. As the resin film, a polyester film, a polyimide film, a polyolefin film, etc. can be used.

[0087] The adhesive strength of the first resin layer side of the double-sided pressure-sensitive adhesive tape of the present disclosure is not particularly limited and can be selected appropriately depending on the purpose, but is preferably 1 N / 20 mm or more and 50 N / 20 mm or less, more preferably 5 N / 20 mm or more and 40 N / 20 mm or less, and even more preferably 10 N / 20 mm or more and 35 N / 20 mm or less.

[0088] The adhesive strength of the first resin layer side of the double-sided pressure-sensitive adhesive tape was measured in accordance with the 180-degree peel adhesion test method of JIS Z 0237:2009, in which the second pressure-sensitive adhesive layer side was backed with a PET film (25 μm thick) and the double-sided pressure-sensitive adhesive tape was cut to a size of 20 mm wide x 100 mm long, the first pressure-sensitive adhesive layer side of the double-sided pressure-sensitive adhesive tape was attached to a stainless steel plate (SUS plate) at a temperature of 23°C and a relative humidity of 50%, a 2 kg roller was rolled back and forth once on the top surface of the tape, and the tape was left to stand under the above-mentioned environmental conditions for 1 hour, and then the tape was peeled off in the 180-degree direction at a speed of 300 mm / min under the above-mentioned conditions using a tensile tester (Tensilon universal testing machine, model: RTF-1210, manufactured by A&D Co., Ltd.).

[0089] The adhesive strength of the second resin layer side of the double-sided pressure-sensitive adhesive tape of the present disclosure is not particularly limited and can be selected appropriately depending on the purpose, but is preferably 1 N / 20 mm or more and 50 N / 20 mm or less, more preferably 5 N / 20 mm or more and 40 N / 20 mm or less, and even more preferably 10 N / 20 mm or more and 30 N / 20 mm or less.

[0090] The adhesive strength of the second resin layer side of the double-sided pressure-sensitive adhesive tape is measured in the same manner as the adhesive strength of the first resin layer side of the double-sided pressure-sensitive adhesive tape, except that the first adhesive layer side of the double-sided pressure-sensitive adhesive tape is backed with a PET film and the second adhesive layer side is attached to a stainless steel plate.

[0091] The shear stress of the double-sided pressure-sensitive adhesive tape of the present disclosure is not particularly limited and can be selected appropriately depending on the purpose, but from the viewpoints of excellent dismantling ability of the tape, resistance to falling when applied to an inclined surface, and excellent tilt durability (excellent tilt retention), it is preferably 50 N or more and 500 N or less, more preferably 100 N or more and 300 N or less, and even more preferably 150 N or more and 250 N or less.

[0092] The shear stress of the double-sided adhesive tape was measured by cutting a piece of double-sided adhesive tape into 25 mm x 25 mm, attaching a stainless steel plate to each of the first adhesive layer side and the second adhesive layer side, and then applying a 2 kg load back and forth once. The tape was then left for 30 minutes at a temperature of 23°C and a relative humidity of 50%. The upper edge of one of the two stainless steel plates and the lower edge of the other stainless steel plate were then gripped with a tensile testing machine (Tensilon universal material testing machine, model: RTF-1210, manufactured by A&D Co., Ltd.) and pulled in the shear direction of the double-sided adhesive tape at a rate of 12.7 mm / min, and the maximum force at which the double-sided adhesive tape broke was measured.

[0093] The holding power of the first resin layer side of the double-sided pressure-sensitive adhesive tape of the present disclosure is not particularly limited and can be selected appropriately depending on the purpose, but is preferably 5 mm or less, more preferably 3 mm or less, even more preferably 1 mm or less, and even more preferably 0 mm.

[0094] The holding power of the first resin layer side of the double-sided pressure-sensitive adhesive tape is measured in accordance with JIS Z 0237:2009 by affixing the first adhesive layer side of a double-sided pressure-sensitive adhesive tape cut to a size of 25 mm x 25 mm to the surface of a stainless steel plate, applying pressure to the top surface by rolling a 2 kg roller back and forth once, leaving it for 1 hour under conditions of a temperature of 23°C and a relative humidity of 50%, and then applying a load of 1 kg in the shear direction in an atmosphere of a temperature of 60°C, and measuring the distance the tape slips after 24 hours.

[0095] The holding power of the second resin layer side of the double-sided pressure-sensitive adhesive tape of the present disclosure is not particularly limited and can be selected appropriately depending on the purpose, but is preferably 5 mm or less, more preferably 3 mm or less, even more preferably 1 mm or less, and particularly preferably 0 mm.

[0096] The holding power of the second resin layer side of the double-sided pressure-sensitive adhesive tape is measured in the same manner as the holding power of the first resin layer side of the double-sided pressure-sensitive adhesive tape, except that the side that is attached to the stainless steel plate is the second pressure-sensitive adhesive layer side.

[0097] The lower limit of the 25% compressive strength of the double-sided pressure-sensitive adhesive tape of the present disclosure is not limited as long as it is 1 KPa or more, and can be selected appropriately depending on the purpose. However, from the viewpoint of achieving both conformability to the adherend and ease of peeling from the adherend, 2 KPa or more is preferred, and 3 KPa or more is more preferred. There is no upper limit to the 25% compressive strength of the double-sided pressure-sensitive adhesive tape, as long as it is 12 KPa or less, and it can be selected appropriately depending on the purpose. However, from the viewpoint of achieving both good conformability to the adherend and ease of peeling from the adherend, it is preferably 10 KPa or less, more preferably 9 KPa or less, and even more preferably 8.5 KPa or less. It is preferable that the numerical range has a lower limit value and an upper limit value that are either of the numerical values ​​shown as the lower limit value and either of the numerical values ​​shown as the upper limit value. The numerical range for the 25% compressive strength of the double-sided pressure-sensitive adhesive tape is not limited as long as it is 1 KPa or more and 12 KPa or less, and can be selected appropriately depending on the purpose. However, in order to achieve both good conformability to the adherend and ease of peeling from the adherend, the numerical range is preferably 2 KPa or more and 10 KPa or less, more preferably 3 KPa or more and 9 KPa or less, and even more preferably 3 KPa or more and 8.5 KPa or less.

[0098] The 25% compressive strength of double-sided adhesive tape is determined in accordance with JIS K 6767:1990 by stacking and adhering 10 pieces of double-sided adhesive tape cut to 25mm x 25mm on a stainless steel plate larger than 25mm x 25mm, leaving it to stand for 24 hours, and then compressing it by 25% of the total thickness using a probe (D = 7mm) at a rate of 4mm / min under conditions of a temperature of 23°C and a relative humidity of 50%.

[0099] The lower limit of the 25% compressive strength per unit thickness (25% compressive strength / thickness) of the double-sided pressure-sensitive adhesive tape is not particularly limited and can be appropriately selected depending on the purpose. However, from the viewpoint of achieving both conformability to the adherend and ease of peeling from the adherend, it is preferable that the lower limit be 1×10 -3 (KPa / μm) or more is preferable, and 2×10 -3 (KPa / μm) or more is more preferable, and 3×10 -3 (KPa / μm) or more is more preferable. The upper limit of the 25% compressive strength per unit thickness (25% compressive strength / thickness) of the double-sided pressure-sensitive adhesive tape is not particularly limited and can be appropriately selected depending on the purpose. However, from the viewpoint of achieving both conformability to the adherend and ease of peeling from the adherend, it is preferable that the upper limit be 14×10 -3 (KPa / μm) or less is preferable, and 13×10 -3 (KPa / μm) or less is more preferable, and 9.5×10 -3 (KPa / μm) or less is more preferable. Among these, from the viewpoint of achieving both conformability to the adherend and ease of peeling from the adherend, the 25% compressive strength per unit thickness (25% compressive strength / thickness) of the double-sided adhesive tape is 1×10 -3 (KPa / μm) or more 14×10 -3(KPa / μm) or less is preferable, and 2×10 -3 (KPa / μm) or more 13×10 -3 (KPa / μm) or less is more preferable, and 3×10 -3 (KPa / μm) or more 9.5×10 -3 (KPa / μm) or less is more preferable.

[0100] The lower limit of the 50% compressive strength of the double-sided pressure-sensitive adhesive tape is not particularly limited and can be appropriately selected depending on the purpose. However, it is preferable that the double-sided pressure-sensitive adhesive tape has both the ability to conform to the adherend and the ease of peeling from the adherend. From this viewpoint, the pressure is preferably 1 KPa or more, more preferably 10 KPa or more, and even more preferably 20 KPa or more. The upper limit of the 50% compressive strength of the double-sided pressure-sensitive adhesive tape is not particularly limited and can be selected appropriately depending on the purpose. However, in order to achieve both good conformability to the adherend and ease of peeling from the adherend, the upper limit is preferably 100 KPa or less, more preferably 50 KPa or less, and even more preferably 30 KPa or less. It is preferable that the numerical range has a lower limit value and an upper limit value that are either of the numerical values ​​shown as the lower limit value and either of the numerical values ​​shown as the upper limit value. Among these, in order to achieve both conformability to the adherend and ease of peeling from the adherend, the 50% compressive strength of the double-sided pressure-sensitive adhesive tape is preferably 1 KPa or more and 100 KPa or less, more preferably 10 KPa or more and 50 KPa or less, and even more preferably 20 KPa or more and 30 KPa or less.

[0101] The 50% compressive strength of the double-sided adhesive tape is measured in the same manner as the 25% compressive strength, except that it is the strength when compressed by 50% of the total thickness with a probe.

[0102] The interlayer strength of the foam substrate in the double-sided pressure-sensitive adhesive tape is not particularly limited and can be selected appropriately depending on the purpose. However, in order to achieve both good conformability to the adherend and ease of peeling from the adherend, the interlayer strength is preferably 1 N / 25 mm or more and 20 N / 25 mm or less, more preferably 2 N / 25 mm or more and 15 N / 25 mm or less, and even more preferably 3 N / 25 mm or more and 12 N / 25 mm or less.

[0103] The interlayer strength of the foam substrate in the double-sided pressure-sensitive adhesive tape is measured by lining the surface of the double-sided pressure-sensitive adhesive tape facing the second adhesive layer with a 25 μm-thick polyester film, cutting the tape to a width of 25 mm, attaching the surface of the double-sided pressure-sensitive adhesive tape facing the first adhesive layer to a stainless steel plate, pressing the tape by rolling it back and forth once with a 2 kg roller at a temperature of 23°C and a relative humidity of 50%, leaving the tape to stand for one hour at a temperature of 23°C and a relative humidity of 50%, and then tearing the double-sided pressure-sensitive adhesive tape from the centre of the thickness direction of the foam substrate in a 180-degree direction at a pulling speed of 300 mm / min under conditions of a temperature of 23°C and a relative humidity of 50%.

[0104] When the double-sided pressure-sensitive adhesive tape is split at the center in the thickness direction of the foam substrate to separate it into a first pressure-sensitive adhesive tape having a first resin layer half in the thickness direction of the foam substrate, the first resin layer, and the first pressure-sensitive adhesive layer in this order, and a second pressure-sensitive adhesive tape having a second resin layer half in the thickness direction of the foam substrate, the second resin layer, and the second pressure-sensitive adhesive layer in this order, the tensile breaking strength of the first pressure-sensitive adhesive tape is preferably 1 MPa or more and 50 MPa or less, more preferably 5 MPa or more and 30 MPa or less, and even more preferably 10 MPa or more and 20 MPa or less. This is because when the tensile breaking strength of the first pressure-sensitive adhesive tape is in the above range, it is possible to achieve both good conformability to an adherend and easy peeling from the adherend.

[0105] The tensile breaking elongation of the first pressure-sensitive adhesive tape is not particularly limited and can be appropriately selected depending on the purpose, but is preferably from 200% to 1000%, more preferably from 250% to 500%, and even more preferably from 270% to 450%. This is because when the tensile breaking elongation of the first pressure-sensitive adhesive tape is in the above range, it can achieve both good conformability to the adherend and ease of peeling from the adherend.

[0106] The tensile strength at break and the tensile elongation at break of the first pressure-sensitive adhesive tape are measured by the same methods as those for measuring the tensile strength at break and the tensile elongation at break of the first resin layer, respectively.

[0107] Furthermore, when the double-sided adhesive tape is split at the center in the thickness direction of the foam substrate to separate it into the first adhesive tape and the second adhesive tape, The tensile breaking strength is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 100 MPa or more and 500 MPa or less, more preferably 150 MPa or more and 400 MPa or less, and even more preferably 200 MPa or more and less than 300 MPa, because when the tensile breaking strength of the second pressure-sensitive adhesive tape is in the above range, ease of punching and ease of peeling from the adherend can both be achieved.

[0108] The tensile strength at break and the tensile elongation at break of the second adhesive tape are measured by the same methods as those for measuring the tensile strength at break and the tensile elongation at break of the first resin layer, respectively.

[0109] According to the double-sided pressure-sensitive adhesive tape of the present disclosure, the first resin layer provided on one side of the foam substrate contains a thermoplastic elastomer, and the 25% compressive strength of the double-sided pressure-sensitive adhesive tape is 1 KPa or more and 12 KPa or less, thereby achieving a sufficiently excellent balance between conformability to the adherend and ease of peeling from the adherend.

[0110] (Goods) The article of the present disclosure includes a double-sided pressure-sensitive adhesive tape, a first adherend adhered to the first pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive tape, and a second adherend adhered to the second pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive tape. The double-sided pressure-sensitive adhesive tape in the article of the present disclosure is as described above in (Double-sided pressure-sensitive adhesive tape).

[0111] The article is not particularly limited and can be appropriately selected depending on the purpose, but display products are preferred. The display product includes a display such as a television or a personal computer, and a housing. The material of the display is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include glass.

[0112] The first adherend is not particularly limited and can be appropriately selected depending on the purpose, but is preferably a display in the display product. The second adherend is not particularly limited and can be appropriately selected depending on the purpose, but is preferably a housing for the display product.

[0113] (Method of dismantling items) The method for dismantling an article of the present disclosure includes a separation step of separating the article described in (Article) above into a first adherend having a first adhesive tape having a portion of the foam base material, the first resin layer, and the first adhesive layer, and a second adherend having a second adhesive tape having a portion of the foam base material, the second resin layer, and the second adhesive layer, and a peeling step of peeling the first adhesive tape from the first adherend and peeling the second adhesive tape from the second adherend. The method for dismantling an article according to the present disclosure includes the separating step and the peeling step, and may further include other steps.

[0114] An example of the method for dismantling the article will now be described with reference to the drawings. Figures 2A to 2C are schematic diagrams showing an example of the method for dismantling the article according to this embodiment. First, as shown in Fig. 2A, an article 20 formed by joining two or more adherends (a first adherend 21, a second adherend 22) via a double-sided adhesive tape 10 is split in the thickness direction of the foam substrate 3 of the double-sided adhesive tape 10 along the in-plane S-S', and separated into a first adherend 21 having a first adhesive tape 11 and a second adherend 22 having a second adhesive tape 12, as shown in Fig. 2B. The first adhesive tape 11 has a part 3a of the foam substrate, a first resin layer 2, and a first adhesive layer 1 in this order, and the first The surface on the pressure-sensitive adhesive layer 1 side is bonded to a first adherend 21. The second pressure-sensitive adhesive tape 12 has a part 3b of the foam substrate, a second resin layer 4, and a second pressure-sensitive adhesive layer 5 in this order, and the surface on the second pressure-sensitive adhesive layer 5 side of the second pressure-sensitive adhesive tape 12 is bonded to a second adherend 22.

[0115] Next, as shown in FIG. 2C , the first adhesive tape 11 is peeled from the first adherend 21, and the second adhesive tape 12 is peeled from the second adherend 22. Specifically, the adhesive tapes are peeled from the adherends by picking up and pulling an end of the first adhesive tape 11, particularly an end of at least the first resin layer 2 of the first adhesive tape 11, to peel the first adhesive tape 11 from the first adherend 21. The second adhesive tape 12 is peeled from the second adherend 22 by picking up and pulling an end of the second adhesive tape 12, particularly an end of at least the second resin layer 4 of the second adhesive tape 12. This allows the article to be easily disassembled into the first adherend 21 and the second adherend 22, from which the double-sided adhesive tape 10 has been removed.

[0116] According to the method for dismantling an article of this embodiment, a double-sided adhesive tape having a foam substrate and predetermined resin layers on both sides is used. Therefore, the double-sided adhesive tape is split at the foam substrate to separate the article into two: a first adherend on which the first adhesive tape (a part of the double-sided adhesive tape) remains, and a second adherend on which the second adhesive tape remains. After that, when peeling the first or second adhesive tape from each adherend, interlayer peeling between the foam substrate and the resin layer or between the resin layer and the adhesive layer is unlikely to occur, allowing the adhesive tape to be easily peeled from the adherend. Furthermore, when the resin layer exhibits a tensile modulus within a predetermined range, a good balance of toughness and elongation is achieved. This makes it easy to pick up the edge of the adhesive tape when peeling it from the adherend, facilitating peeling and preventing tearing during peeling. Furthermore, it is possible to prevent tape residue on the adherend due to peeling between the layers of the adhesive tape. Thus, the excellent reworkability of the double-sided adhesive tape can further enhance the ease of dismantling articles and the reusability of parts.

[0117] <Goods> In the method for dismantling an article according to the present disclosure, the article is as described above in (article).

[0118] <Separation process> In the article disassembly method of the present disclosure, the separation step is a step of separating the article into a first adherend having a first adhesive tape having a portion of the foam substrate, the first resin layer, and the first adhesive layer, and a second adherend having a second adhesive tape having a portion of the foam substrate, the second resin layer, and the second adhesive layer.

[0119] A preferred method for separating the article into a first adherend having a first adhesive tape and a second adherend having a second adhesive tape is to split the foam substrate in the thickness direction to separate the article into two. Examples of such a separation method include a method of cutting the foam substrate along the in-plane direction at a desired position in the thickness direction. Specific examples include a method of fixing one side of the article in the thickness direction and slicing the foam substrate in the in-plane direction at a desired position in the thickness direction, and a method of making an incision in the in-plane direction at a desired position in the thickness direction of the foam substrate and tearing the foam substrate starting from the incision. The in-plane direction is a direction perpendicular to the thickness direction. The foam substrate can be split using a general slicing machine. By splitting the article at the foam substrate, the adhesive tape remaining on the first adherend can include the first resin layer, and the adhesive tape remaining on the second adherend can include the second resin layer.

[0120] The split position in the thickness direction of the foam base material is not particularly limited and can be appropriately selected depending on the purpose. For example, it may be at the center in the thickness direction of the foam base material, or at one side of the foam base material. It may be in the vicinity of the oil layer. The thickness of the foam substrate after splitting in the first pressure-sensitive adhesive tape and the second pressure-sensitive adhesive tape can be appropriately set depending on the split position.

[0121] <Peeling process> The peeling step is a step of peeling the first adhesive tape from the first adherend and peeling the second adhesive tape from the second adherend.

[0122] The peeling step can be performed by pulling the adhesive tape. The direction in which the adhesive tape is pulled is not particularly limited, and it may be a direction forming a desired angle with respect to the adhesive surface, or may be an in-plane direction (a direction perpendicular to the thickness direction). Among these, peeling by pulling in the in-plane direction is preferred. Examples of methods for peeling the first adhesive tape from the first adherend include a method in which an end of the first adhesive tape, more specifically, an end of at least the first resin layer of the first adhesive tape, is picked up and pulled to peel the first adhesive tape from the first adherend.Similarly, examples of methods for peeling the second adhesive tape from the second adherend include a method in which an end of the second adhesive tape, more specifically, an end of at least the second resin layer of the second adhesive tape, is picked up and pulled to peel the second adhesive tape from the second adherend. The method for picking up the end of the adhesive tape is not particularly limited, and can be a general-purpose method such as scraping it up with a fingernail.

[0123] According to the method for dismantling an article disclosed herein, even if the adhesive tape remaining on each adherend after separation is thin, the adhesive tape each contains a specified resin layer, and therefore the end of the adhesive tape can be easily picked up when peeling, making it easy to get an opportunity to peel it off, and the tape is less likely to tear during peeling, and no adhesive residue is left behind, making peeling easy and simple. [Example]

[0124] Examples of the present invention will be described below, but the present invention is not limited to these examples in any way.

[0125] [Foam laminate sheet] The foam laminate sheets S1 to S14 shown in Tables 1 to 3 below were used. In the table, manufacturers A to G are manufacturers of the foam laminate sheets, as follows: The surfaces of the foam laminate sheets S1 to S14 were each subjected to a corona treatment to adjust the wetting index to 54 mN / m. A:ShengYing New Material Technology(Changzhou)Co.,Ltd B: INOAC Corporation C:Xiangyuan New Material The resins in the table are as follows: PU: Polyurethane TPU: Thermoplastic polyurethane elastomer PE: Polyethylene PET: Polyethylene terephthalate

[0126] [Table 1]

[0127] [Table 2]

[0128] [Table 3]

[0129] [Preparation of adhesive] <Adhesive A> 97.98 parts by mass of n-butyl acrylate, 2 parts by mass of acrylic acid, and 0.02 parts by mass of 4-hydroxybutyl acrylate were solution polymerized in an ethyl acetate solution at 90°C for 6 hours using 0.3 parts by mass of azobisisobutyronitrile as a polymerization initiator, to obtain an acrylic polymer (1) having a weight-average molecular weight of 500,000. With respect to 100 parts by mass of the acrylic polymer (1), “D-135” (Arakawa Chemical Industries, Ltd.) A pressure-sensitive adhesive solution with a solids content of 40% by mass was obtained by mixing 5 parts by mass of "KE-100" (polymerized rosin ester manufactured by Arakawa Chemical Industries, Ltd.), 20 parts by mass of "KE-100" (disproportionated rosin ester manufactured by Arakawa Chemical Industries, Ltd.), and 25 parts by mass of "FTR6100" (petroleum resin manufactured by Mitsui Chemicals, Inc.), and then adding ethyl acetate.

[0130] Adhesive A was obtained by mixing 100 parts by mass of the adhesive solution with 1.4 parts by mass of an isocyanate crosslinking agent (solid content 40% by mass) and 0.2 parts by mass of an epoxy crosslinking agent (solid content 5% by mass) and stirring. The pressure-sensitive adhesive layer obtained using the pressure-sensitive adhesive A had a peak temperature of tan δ of 0° C. and a gel fraction of 10% by mass.

[0131] <Adhesive B> In a reaction vessel equipped with a stirrer, a condenser, a thermometer, and a dropping funnel, the materials shown below were dissolved in 100 parts by mass of ethyl acetate in the following proportions, and after nitrogen substitution, polymerization was carried out at 80°C for 12 hours to obtain an ethyl acetate solution of acrylic copolymer (2) having a weight-average molecular weight of 600,000. n-Butyl acrylate: 75.0 parts by mass 2-Ethylhexyl acrylate: 19.0 parts by mass Vinyl acetate: 3.9 parts by weight Acrylic acid: 2.0 parts by weight 2-Hydroxyethyl acrylate: 0.1 parts by mass 2,2'-Azobisisobutylnitrile (polymerization initiator): 0.1 parts by mass 100 parts by mass (solid content) of the acrylic copolymer (2), 10 parts by mass of polymerized rosin pentaerythritol ester (Pensel D-135, manufactured by Arakawa Chemical Industries, Ltd., softening point 135°C), and 10 parts by mass of disproportionated rosin glycerin ester (Super Ester A-100, manufactured by Arakawa Chemical Industries, Ltd.) were mixed and stirred, and then ethyl acetate was added to obtain an acrylic adhesive having an acrylic polymer solid content of 40% by mass.

[0132] Next, 100 parts by mass of the acrylic adhesive, 1.67 parts by mass of an isocyanate crosslinking agent (solid content 40% by mass), 0.12 parts by mass of an epoxy crosslinking agent (solid content 5% by mass), and 70 parts by mass of ethyl acetate were mixed for 10 minutes using a dispersion stirrer to obtain adhesive B.

[0133] <Adhesive C> In a reaction vessel equipped with a stirrer, a reflux condenser, a thermometer, a dropping funnel, and a nitrogen gas inlet, 90.0 parts by mass of butyl acrylate, 5.0 parts by mass of methyl methacrylate, 4.0 parts by mass of acrylic acid, 0.05 parts by mass of 4-hydroxybutyl acrylate, and 0.2 parts by mass of 2,2'-azobisisobutylnitrile as a polymerization initiator were dissolved in ethyl acetate, and the mixture was polymerized at 70°C for 8 hours to obtain a solution of acrylic copolymer (3) having a weight-average molecular weight of 700,000.

[0134] The solution of the acrylic copolymer (3) was diluted with ethyl acetate to a solid content of 30%, and 100 parts by mass of the acrylic copolymer (3) was mixed with 0.43 parts by mass of an isocyanate crosslinking agent (solid content 40% by mass) and 0.18 parts by mass of an epoxy crosslinking agent (solid content 5% by mass) and stirred to obtain a pressure-sensitive adhesive C.

[0135] [Manufacturing double-sided adhesive tape] Example 1 The double-sided adhesive tape was prepared in the following manner. The adhesive A was applied to the release-treated surface of a release liner (a 75 μm-thick PET film with one side treated for release) so that the thickness after drying would be 80 μm, and then dried at 85° C. for 3 minutes to form an adhesive layer. Two of these were prepared, and the first and second resin layers of the foam laminate sheet S1 were used. The laminate was then laminated at 90° C. with a roll at a linear pressure of 5 kg / cm, and aged in a 40° C. environment for 120 hours to obtain double-sided adhesive tape 1 (referred to as tape 1).

[0136] Example 2 Double-sided pressure-sensitive adhesive tape 2 (Tape 2) was produced in the same manner as in Example 1, except that foam laminate sheet S2 was used instead of foam laminate sheet S1.

[0137] Example 3 Double-sided pressure-sensitive adhesive tape 3 (Tape 3) was produced in the same manner as in Example 1, except that foam laminate sheet S3 was used instead of foam laminate sheet S1.

[0138] Example 4 Double-sided pressure-sensitive adhesive tape 4 (Tape 4) was produced in the same manner as in Example 1, except that foam laminate sheet S4 was used instead of foam laminate sheet S1.

[0139] Example 5 Double-sided pressure-sensitive adhesive tape 5 (Tape 5) was produced in the same manner as in Example 1, except that foam laminate sheet S5 was used instead of foam laminate sheet S1.

[0140] Example 6 Double-sided pressure-sensitive adhesive tape 6 (Tape 6) was produced in the same manner as in Example 1, except that foam laminate sheet S6 was used instead of foam laminate sheet S1.

[0141] Example 7 Double-sided pressure-sensitive adhesive tape 7 (Tape 7) was produced in the same manner as in Example 1, except that foam laminate sheet S7 was used instead of foam laminate sheet S1.

[0142] Example 8 Double-sided adhesive tape 8 (Tape 8) was produced in the same manner as in Example 1, except that adhesive B was used instead of adhesive A, and foam laminate sheet S11 was used instead of foam laminate sheet S1.

[0143] (Comparative Example 1) Double-sided pressure-sensitive adhesive tape 9 (Tape 9) was produced in the same manner as in Example 1, except that foam laminate sheet S8 was used instead of foam laminate sheet S1.

[0144] (Comparative Example 2) Double-sided pressure-sensitive adhesive tape 10 (tape 10) was produced in the same manner as in Example 1, except that foam laminate sheet S9 was used instead of foam laminate sheet S1.

[0145] (Comparative Example 3) Double-sided adhesive tape 11 (tape 11) was produced in the same manner as in Example 1, except that adhesive B was used instead of adhesive A and foam laminate sheet S10 was used instead of foam laminate sheet S1.

[0146] Comparative Example 4 Double-sided adhesive tape 12 (tape 12) was produced in the same manner as in Example 1, except that adhesive C was used instead of adhesive A and foam laminate sheet S12 was used instead of foam laminate sheet S1.

[0147] (Comparative Example 5) A double-sided pressure-sensitive adhesive tape 13 (tape 13) was produced in the same manner as in Example 1, except that a foam laminate sheet S13 was used instead of the foam laminate sheet S1.

[0148] (Comparative Example 6) A double-sided pressure-sensitive adhesive tape 14 (tape 14) was produced in the same manner as in Example 1, except that a foamed laminate sheet S14 was used instead of the foamed laminate sheet S1.

[0149] [evaluation] The double-sided pressure-sensitive adhesive tapes produced in the Examples and Comparative Examples, as well as the resin layers and foam substrates in each Example and Comparative Example, were evaluated using the methods described below. The results of each evaluation are shown in Tables 4 to 6.

[0150] <Thickness> The measurement is carried out using a dial gauge in accordance with JIS K 6250:2019. Specifically, the contact surface with the adhesive tape 1 is a flat surface with a diameter of 8 mm. This is the value measured when the page is brought into contact with the sheet with a force of 0.51 N. Note that this thickness does not include the thickness of the release sheet 4. The thickness can be measured using, for example, a thickness gauge FFG-6 manufactured by Ozaki Seisakusho.

[0151] <Bulk density of foam substrate> The bulk density of the foam substrate was determined by measuring the weight of a foam substrate cut into 100 mm x 100 mm pieces using a 0.1 mg electronic balance in accordance with JIS K 6767:1990, and dividing the weight by the volume of the cut foam substrate.

[0152] <Tensile Breaking Strength of First Resin Layer> The tensile breaking strength of the first resin layer was determined in accordance with JIS K 6767:1990 by pulling a piece of the first resin layer cut into a 1 cm width with a 2 cm gauge interval at a temperature of 23°C and a relative humidity of 50% at a pulling speed of 300 mm / min using a tensile testing machine (Tensilon universal material testing machine, model: RTF-1210, manufactured by A&D Co., Ltd.), and the stress per unit area (maximum stress) at which the first resin layer broke was measured. The tensile breaking strength of the second resin layer was measured in the same manner as the tensile breaking strength of the first resin layer.

[0153] <Tensile Modulus of First Resin Layer> The tensile modulus of the first resin layer was determined in accordance with JIS K 6767:1990 by pulling a piece of the first resin layer cut to a width of 1 cm with a gauge interval of 2 cm at a temperature of 23°C and a relative humidity of 50% at a pulling speed of 300 mm / min using a tensile testing machine (Tensilon universal material testing machine, model: RTF-1210, manufactured by A&D Co., Ltd.), and determining the slope of the tensile strength (the slope of the rising edge of the stress-strain curve) when the elongation was 1% or more and 3% or less. The tensile modulus of elasticity of the second resin layer was measured in the same manner as that for the tensile modulus of elasticity of the first resin layer.

[0154] <Tensile elongation at break of first resin layer> The tensile breaking elongation of the first resin layer was determined in accordance with JIS K 6767:1990 by pulling a piece of the first resin layer cut into a 1 cm width with a 2 cm gauge interval at a temperature of 23°C and a relative humidity of 50% using a tensile testing machine (Tensilon universal testing machine, model: RTF-1210, manufactured by A&D Co., Ltd.) at a pulling speed of 300 mm / min, and by measuring the elongation at which the first resin layer broke. The tensile elongation at break of the second resin layer is measured in the same manner as the tensile elongation at break of the first resin layer. did.

[0155] <Peeling strength of the surface of the first resin layer facing the first pressure-sensitive adhesive layer (by method 31B)> The peel force (31B method) of the surface of the first resin layer facing the first adhesive layer was measured by bonding the second resin layer side of a foam laminate sheet (" / " indicates the lamination interface) consisting of a first resin layer / foam substrate / second resin layer to a stainless steel (SUS) plate using a strong adhesive double-sided tape (manufactured by DIC Corporation, product name #8800CH), bonding a single-sided adhesive tape (manufactured by Nitto Denko Corporation, polyester adhesive tape No. 31B) to the first resin layer side of the laminate, applying pressure once back and forth with a 2 kg roll, leaving it to stand for 1 hour, and then peeling the single-sided adhesive tape in a 180° direction at a speed of 300 mm / min.

[0156] <25% compression strength of foam laminate sheet> The 25% compression strength of a foam laminate sheet (a foam laminate sheet consisting of three layers: a first resin layer, a foam base material, and a second resin layer) was determined in accordance with JIS K 6767:1990 by placing a foam base material cut to 25 mm x 25 mm on a stainless steel plate larger than the foam base material, with the second resin layer side facing the stainless steel plate, and pressing the foam base material with a probe (D = 7 mm) at a rate of 0.5 mm / min under conditions of a temperature of 23°C and a relative humidity of 50%, thereby compressing the sheet to 25% of its total thickness.

[0157] <25% compression strength of double-sided adhesive tape> The 25% compressive strength of the double-sided adhesive tape was determined in accordance with JIS K 6767:1990 by stacking and adhering 10 pieces of double-sided adhesive tape cut to 25mm x 25mm on a stainless steel plate larger than 25mm x 25mm, leaving it to stand for 24 hours, and then compressing it by 25% of the total thickness with a probe (D = 7mm) at a rate of 4mm / min under conditions of a temperature of 23°C and a relative humidity of 50%.

[0158] <50% compression strength of double-sided adhesive tape> The 50% compression strength of the double-sided adhesive tape was measured in the same manner as the 25% compression strength, except that the strength was measured when the double-sided adhesive tape was compressed by 50% of the total thickness with a probe.

[0159] <Interlaminar strength of foam substrate in double-sided adhesive tape> The interlayer strength of the foam substrate in the double-sided adhesive tape was measured by lining the side of the double-sided adhesive tape facing the second adhesive layer with a 25 μm thick polyester film, cutting the tape to a width of 25 mm, attaching the side of the double-sided adhesive tape facing the first adhesive layer to a stainless steel plate, pressing the tape together with a 2 kg roller moving back and forth once at a temperature of 23°C and a relative humidity of 50%, allowing the tape to stand for 1 hour at a temperature of 23°C and a relative humidity of 50%, and then tearing the double-sided adhesive tape from the centre of the thickness direction of the foam substrate in a 180-degree direction at a pulling speed of 300 mm / min at a temperature of 23°C and a relative humidity of 50%.

[0160] <Adhesive strength of the first resin layer side of the double-sided adhesive tape> The adhesive strength of the first resin layer side of the double-sided pressure-sensitive adhesive tape was measured in accordance with the 180-degree peel adhesion test method of JIS Z 0237:2009. The second pressure-sensitive adhesive layer side of the double-sided pressure-sensitive adhesive tape was lined with a PET film (25 μm thick) and cut to a size of 20 mm wide x 100 mm long. The first pressure-sensitive adhesive layer side of the double-sided pressure-sensitive adhesive tape was attached to a stainless steel plate (SUS plate) at a temperature of 23°C and a relative humidity of 50%, and a 2 kg roller was rolled back and forth once on the upper surface of the tape to press the tape together. The tape was then left under the above conditions for 1 hour, and the tape was then peeled off in the 180-degree direction at a speed of 300 mm / min using a tensile tester (Tensilon universal testing machine, model: RTF-1210, manufactured by A&D Co., Ltd.). The value measured was recorded as the value measured under the above conditions.

[0161] <Adhesive strength of the second resin layer side of the double-sided adhesive tape> The adhesive strength of the second resin layer side of the double-sided adhesive tape was measured in the same manner as the adhesive strength of the first resin layer side of the double-sided adhesive tape, except that the first adhesive layer side of the double-sided adhesive tape was backed with a PET film and the second adhesive layer side was attached to a stainless steel plate.

[0162] <Shear stress of double-sided adhesive tape> The shear stress of the double-sided adhesive tape was measured by attaching a stainless steel plate to each of the first adhesive layer side and the second adhesive layer side of the double-sided adhesive tape cut into a 25 mm × 25 mm piece, applying a 2 kg load back and forth once, and then leaving the tape for 30 minutes at a temperature of 23°C and a relative humidity of 50%.Then, using a tensile testing machine (Tensilon universal material testing machine, model: RTF-1210, manufactured by A&D Co., Ltd.), the upper edge of one of the two stainless steel plates and the lower edge of the other stainless steel plate were grasped and pulled in the shear direction of the double-sided adhesive tape at a rate of 12.7 mm / min, and the maximum force at which the double-sided adhesive tape broke was recorded.

[0163] <Holding power of the first resin layer side of the double-sided adhesive tape> The holding strength of the first resin layer side of the double-sided adhesive tape was measured in accordance with JIS Z 0237:2009 by attaching the first adhesive layer side of a double-sided adhesive tape cut to a size of 25 mm x 25 mm to the surface of a stainless steel plate, applying pressure to the top surface by rolling a 2 kg roller back and forth once, leaving the tape to stand for 1 hour under conditions of a temperature of 23°C and a relative humidity of 50%, and then applying a load of 1 kg in the shear direction in an atmosphere of a temperature of 60°C and a relative humidity of 50%, and measuring the distance the tape slipped after 24 hours.

[0164] <Holding power of the second resin layer side of the double-sided adhesive tape> The holding power of the second resin layer side of the double-sided adhesive tape was measured in the same manner as the holding power of the first resin layer side of the double-sided adhesive tape, except that the side that was attached to the stainless steel plate was the second adhesive layer side.

[0165] <Dismantability> The double-sided adhesive tape was cut to a size of 3 mm x 40 mm, and the side with the first adhesive layer was attached to a glass plate (thickness 1 mm), and the side with the second adhesive layer was attached to a stainless steel plate (thickness 1 mm). The tape was then pressed back and forth twice with a 2 kg roll and allowed to stand for 24 hours under conditions of a temperature of 60°C and a relative humidity of 90%, to obtain an article (a composite having a glass plate, double-sided adhesive tape, and stainless steel plate, in that order). The foam substrate in the article was sliced ​​with a knife at the center of its thickness in an environment of 23°C, and it was confirmed whether the article could be separated into a glass plate side member (glass plate with first adhesive tape) having a glass plate, a foam substrate remaining on the glass plate side, a first adhesive tape consisting of a first resin layer and a first adhesive layer, and a stainless steel plate side member (stainless steel plate with second adhesive tape) having a stainless steel plate, a foam substrate remaining on the stainless steel plate side, a second adhesive tape consisting of a second resin layer and a second adhesive layer (stainless steel plate with second adhesive tape) (whether the article could be split at the foam substrate, i.e., splittability).

[0166] In addition, when the first adhesive tape was peeled from the glass plate at a speed of 300 mm / min in a direction of 135° to the glass plate side member, the adhesive residue and peeling condition of the first adhesive tape were confirmed (dismantleability on the first resin layer side). Similarly, when the second adhesive tape was peeled from the stainless steel plate side member in a 135° direction at a speed of 300 mm / min, the adhesive residue and peeling condition of the second adhesive tape were confirmed (dismantleability of the second resin layer side). Dismantling properties were evaluated based on the splitting properties and the peeling properties of the first and second adhesive tapes after splitting, according to the following criteria.

[0167] (standard) ◎: Can be cut with a knife (splittable). No adhesive residue when peeling off the first or second adhesive tape. The adhesive tape did not break when peeled off (0 times) ○: Can be cut with a knife (splittable). When peeling off the first or second adhesive tape, it peeled off without leaving any adhesive residue, but the adhesive tape broke (1 to 4 times). △: Can be cut with a knife (splittable). When the first or second adhesive tape was peeled off, it was peeled off without leaving any adhesive residue, but the adhesive tape broke (5 or more times). ×: Cannot be cut with a knife (no splitting ability)

[0168] <Follow-up ability> As shown in Figure 3 (the upper figure in Figure 3 is a plan view, and the lower figure in Figure 3 is an end view seen from the end face side where the double-sided adhesive tape 10 is provided), a step 51 with a width of 30 mm and a height of 0.17 mm was formed on the surface of a stainless steel plate 50 using a single-sided polycarbonate film tape in the width direction of the stainless steel plate 50, and the double-sided adhesive tape 10 cut to a size of 5 mm x 80 mm was attached so that the surface of the first adhesive layer facing the stainless steel plate 50 and the longitudinal direction of the double-sided adhesive tape 10 facing in the same direction as the width direction of the step 51 followed the step 51. After leaving it to stand at room temperature for 5 minutes, the adhesion between the double-sided adhesive tape 10 and the edge of the step 51 (X in the lower diagram of Figure 3) was observed using a microscope (100x magnification) and evaluated according to the following criteria. FIG. 4 shows a micrograph of the area between the double-sided adhesive tape 10 and the edge of the step 51 in the evaluation of compliance.

[0169] (standard) ◎: Followed without gaps (gap width 300 mm or less, area 20,000 μm 2 below) △: Following, but gaps occurred (gap width over 300mm and 600mm or less, area 20000μm 2 Super 50000μm 2 below) ×: A large gap occurred and it was not possible to follow (the gap width was over 600 μm and the area was 50,000 μm) 2 super)

[0170] <Tensile Breaking Strength and Tensile Breaking Elongation of First Pressure-Sensitive Adhesive Tape After Separation (Splitting)> Each double-sided adhesive tape was sliced ​​in the plane direction at the center of the thickness direction of the foam substrate to create a first adhesive tape consisting of half of the foam substrate, a first resin layer, and a first adhesive layer, and the tensile breaking strength and tensile breaking elongation of the first adhesive tape were measured using a method similar to the method for measuring the tensile breaking strength and tensile breaking elongation of the first resin layer.

[0171] <Tilt drop test (tilt retention force)> Two pieces of double-sided adhesive tape cut to a size of 3 mm x 40 mm were prepared, and the first adhesive layer of one double-sided adhesive tape was bonded to the second adhesive layer of the other double-sided adhesive tape to form a laminate.The surface of the laminate with the first adhesive layer was bonded to a glass plate (thickness 1 mm), and the surface with the second adhesive layer was bonded to a stainless steel plate (thickness 1 mm), and the laminate was pressed back and forth twice with a 2 kg roll. After 5 minutes, the stainless steel plate was tilted at 45°C with the stainless steel plate surface facing downwards under conditions of a temperature of 60°C and a relative humidity of 90%, and a 30g load was applied to the center of the stainless steel plate, and the time it took for the double-sided adhesive tape to fall was measured. In the table, ">24h" indicates that the tape did not fall after 24 hours.

[0172] [Table 4]

[0173] [Table 5]

[0174] [Table 6]

[0175] The results in Tables 4 to 6 show that a double-sided adhesive tape having a first pressure-sensitive adhesive layer, a first resin layer, a foam substrate, a second resin layer, and a second pressure-sensitive adhesive layer in this order, wherein the first resin layer contains a thermoplastic elastomer, and wherein the 25% compressive strength of the double-sided adhesive tape is 1 KPa or more and 12 KPa or less, satisfies both the ability to conform to the adherend and the ease of peeling from the adherend.

[0176] The present invention includes, for example, the following aspects. <1> a first pressure-sensitive adhesive layer, a first resin layer, a foam substrate, a second resin layer, and a second pressure-sensitive adhesive layer, in this order; the first resin layer contains a thermoplastic elastomer, The double-sided pressure-sensitive adhesive tape is characterized in that the 25% compressive strength of the double-sided pressure-sensitive adhesive tape is 1 KPa or more and 12 KPa or less. <2> the second resin layer is different from the first resin layer; <1> 1. The double-sided adhesive tape according to claim 1. <3> The second resin layer has a tensile strength at break higher than the first resin layer. <1> or the above <2> 1. The double-sided adhesive tape according to claim 1. <4> The first resin layer has a tensile strength of 56 MPa or less. <1> From the above <3> 1. The double-sided pressure-sensitive adhesive tape according to claim 1, wherein the adhesive layer is a <5> the tensile modulus of the first resin layer is 10 MPa or more and 56 MPa or less; <1> From the above <4> 1. The double-sided pressure-sensitive adhesive tape according to claim 1, wherein the adhesive layer is a <6> The first resin layer has a tensile elongation at break of 200% or more. <1> From the above <5> 1. The double-sided pressure-sensitive adhesive tape according to claim 1, wherein the adhesive layer is a <7> The thickness of the first resin layer is 10 μm or more and 30 μm or less. <1> From the above <6> 1. The double-sided pressure-sensitive adhesive tape according to claim 1, wherein the adhesive layer is a <8> The first resin layer contains a polyurethane-based thermoplastic elastomer. <1> From the above <7> 1. The double-sided pressure-sensitive adhesive tape according to claim 1, wherein the adhesive layer is a <9> The second resin layer contains a polyester resin. <1> From the above <8> 1. The double-sided pressure-sensitive adhesive tape according to claim 1, wherein the adhesive layer is a <10> The shear stress of the double-sided adhesive tape is 50N or more and 500N or less. <1> From the above <9> 1. The double-sided pressure-sensitive adhesive tape according to claim 1, wherein the adhesive layer is a <11> The double-sided adhesive tape has a 25% compressive strength per unit thickness of 14×10 -3 (KPa / μm) or less, <1> From the above <10> 1. The double-sided pressure-sensitive adhesive tape according to claim 1, wherein the adhesive layer is a <12> The thickness of the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer is independently 65 μm or more and 100 μm or less. <1> From the above <11> 1. The double-sided pressure-sensitive adhesive tape according to claim 1, wherein the adhesive layer is a <13> The foam substrate is a polyurethane foam. <1> From the above <12> 1. The double-sided pressure-sensitive adhesive tape according to claim 1, wherein the adhesive layer is a <14> The thickness of the foam substrate is 500 μm or more and 2000 μm or less. <1> From the above <13> 1. The double-sided pressure-sensitive adhesive tape according to claim 1, wherein the adhesive layer is a <15> The aforementioned <1> from <14> an article comprising the double-sided pressure-sensitive adhesive tape according to any one of the above, a first adherend adhered to the first pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive tape, and a second adherend adhered to the second pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive tape. <16> the article is a display product; the first adherend is a display in the display product, the second adherend is a housing of the display product; <15> The article is described in <17> The aforementioned <15> or the above <16> A method for dismantling an article according to the present invention, The article is provided with a first adherend including a first pressure-sensitive adhesive tape having a portion of the foam substrate, the first resin layer, and the first pressure-sensitive adhesive layer; a second adherend comprising a second pressure-sensitive adhesive tape having a part of the foam substrate, the second resin layer, and the second pressure-sensitive adhesive layer; Peeling the first pressure-sensitive adhesive tape from the first adherend; The method for dismantling an article comprises peeling off the second adhesive tape from the second adherend. [Explanation of symbols]

[0177] 1 First adhesive layer 2. First resin layer 3. Foam substrate 3a Part of foam substrate 3b Part of foam substrate 4 Second resin layer 5 Second adhesive layer 10 double-sided adhesive tape 11 First adhesive tape 12 Second adhesive tape 20 Goods 21 First adherend 22 Second adherend 50 Stainless steel plate 51 Steps

Claims

1. a first pressure-sensitive adhesive layer, a first resin layer, a foam substrate, a second resin layer, and a second pressure-sensitive adhesive layer, in this order; the first resin layer contains a thermoplastic elastomer, A double-sided pressure-sensitive adhesive tape, characterized in that the 25% compressive strength of the double-sided pressure-sensitive adhesive tape is 1 KPa or more and 12 KPa or less.

2. The double-sided pressure-sensitive adhesive tape of claim 1 , wherein the second resin layer is different from the first resin layer.

3. The double-sided pressure-sensitive adhesive tape according to claim 1 , wherein the second resin layer has a tensile modulus higher than the tensile breaking strength of the first resin layer.

4. The double-sided pressure-sensitive adhesive tape according to claim 1 , wherein the first resin layer has a tensile strength at break of 56 MPa or less.

5. The double-sided pressure-sensitive adhesive tape according to claim 1 , wherein the first resin layer has a tensile modulus of elasticity of 10 MPa or more and 56 MPa or less.

6. The double-sided pressure-sensitive adhesive tape according to claim 1 , wherein the first resin layer has a tensile elongation at break of 200% or more.

7. The double-sided pressure-sensitive adhesive tape according to claim 1 , wherein the first resin layer has a thickness of 10 μm or more and 30 μm or less.

8. The double-sided pressure-sensitive adhesive tape according to claim 1 , wherein the first resin layer comprises a polyurethane-based thermoplastic elastomer.

9. The double-sided pressure-sensitive adhesive tape according to claim 1 , wherein the second resin layer comprises a polyester-based resin.

10. The double-sided pressure-sensitive adhesive tape according to claim 1 , wherein the double-sided pressure-sensitive adhesive tape has a shear stress of 50 N or more and 500 N or less.

11. The double-sided adhesive tape has a 25% compressive strength per unit thickness of 14 x 10 －３ The double-sided pressure-sensitive adhesive tape according to claim 1, wherein the viscosity is 100 kPa / μm or less.

12. The double-sided pressure-sensitive adhesive tape according to claim 1 , wherein the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer each independently have a thickness of 65 μm or more and 100 μm or less.

13. The double-sided pressure-sensitive adhesive tape according to claim 1 , wherein the foam substrate is a polyurethane foam.

14. The double-sided pressure-sensitive adhesive tape according to claim 1 , wherein the foam substrate has a thickness of 500 μm or more and 2000 μm or less.

15. 15. An article comprising: the double-sided pressure-sensitive adhesive tape according to claim 1; a first adherend adhered to the first pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive tape; and a second adherend adhered to the second pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive tape.

16. the article is a display product; the first adherend is a display in the display product, The article of claim 15 , wherein the second substrate is a housing in the display product.

17. The method for dismantling an article according to claim 15, The article is provided with a first adherend including a first pressure-sensitive adhesive tape having a portion of the foam substrate, the first resin layer, and the first pressure-sensitive adhesive layer; a second adherend comprising a second pressure-sensitive adhesive tape having a part of the foam substrate, the second resin layer, and the second pressure-sensitive adhesive layer; Peeling the first pressure-sensitive adhesive tape from the first adherend; A method for dismantling an article, comprising peeling the second adhesive tape from the second adherend.

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