Adhesive tape and method for producing component using the same

Abstract

To provide an adhesive tape which has a temporary fixing property capable of holding an adherend before elongation, is capable of peeling from an adherend in a low-elongation region in the stretching step and is further capable of suppressing re-attachment to the adherend and to provide a method for producing a component using the adhesive tape.SOLUTION: There is provided an adhesive tape having a base material having stretchability and an adhesive layer containing a filler, wherein the dissolution parameter value of the filler is 8 or more and 20 or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an adhesive tape used for temporary fixing of components, particularly for temporary fixing of microcomponents such as MLCCs during production and transportation. In particular, the present disclosure relates to an adhesive tape having stretch-release properties that allows it to be stretched (stretched) and peeled from an adherend by pulling. [Background technology]

[0002] In the manufacture of electronic components such as semiconductor wafers, multilayer ceramic capacitors (hereinafter sometimes referred to as MLCCs), and inductors, a workpiece is fixed onto an adhesive tape, and one or more processed products (electronic components) are manufactured through processes such as grinding, processing, transport, and chipping by dicing. The processed products are then peeled off and released from the adhesive tape. Tapes used to temporarily fix the workpieces and processed products (collectively sometimes referred to as processed products, etc.) in such manufacturing processes are sometimes referred to as "temporary fixing tapes," "process tapes," etc. Tapes used for temporary fixing are required to have adhesive properties that enable them to fix and hold the adherend, and to be easily releasable when the temporary fixation is released.

[0003] For example, Patent Document 1 discloses a heat-foaming release tape in which heat-expandable balloons in the adhesive layer foam or expand when heated, thereby reducing adhesive strength, and a method of fixing a workpiece to the heat-foaming release tape and then applying heat to the tape after processing to peel the processed product from the tape. Patent Document 2 also discloses an active energy ray-curable release tape in which the adhesive layer is cured by irradiation with active energy rays such as UV rays, thereby reducing adhesive strength, and a method of fixing a workpiece to the active energy ray-curable release tape and then applying UV light after processing to peel the processed product from the tape.

[0004] However, when heat-foaming and peeling tapes are used, if the heating time or temperature is increased to sufficiently foam or expand the heat-expandable balloon during heat peeling, the processed product temporarily fixed to the tape is susceptible to thermal degradation. In particular, in the manufacturing process of MLCCs, heating a laminated thin film is likely to cause quality problems such as cracking. Furthermore, when a processed product is subjected to thermal processing on the tape, the heat-expandable balloon in the adhesive layer may foam or expand during processing, causing the processed product to detach.

[0005] Furthermore, in a method for manufacturing a processed product using an active energy ray-curable peelable tape, the active energy rays irradiated when the tape is peeled off may cause the processed product to be affected by photodegradation, etc. Furthermore, if the amount of active energy rays irradiated to the tape is insufficient, the adhesive strength of the tape may not be sufficiently reduced, and the processed product may not be easily peeled off from the tape or adhesive residue may remain on the processed product. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-229399 [Patent Document 2] Japanese Patent Application Laid-Open No. 2002-121511 [Patent Document 3] Japanese Patent Application Laid-Open No. 2016-29155 [Patent Document 4] Japanese Patent Application Publication No. 2017-171772 Summary of the Invention [Problem to be solved by the invention]

[0007] In view of the problems with conventional process tapes that use heat-foaming release or active energy ray curing release, the present inventors have been investigating the use of pressure-sensitive adhesive tapes with stretch-releasing properties (hereinafter sometimes referred to as stretch-releasing tapes) for process applications as an alternative to conventional process tapes. Stretch-releasing tapes are tape that can be released from an adherend by gripping and pulling a portion of the tape, resulting in stretching deformation. They have traditionally been developed for applications involving bonding two components. For example, Patent Document 3 discloses a pressure-sensitive adhesive sheet for portable electronic devices that has a shear adhesive strength, breaking strength, and elongation at break that are each above a predetermined value. Patent Document 4 also discloses a pressure-sensitive adhesive sheet that has a total thickness, an initial adhesive strength A to polycarbonate, and a tensile peel stress B that are each within a predetermined range. The stretch-releasing tapes disclosed in these patent documents are all intended for applications involving bonding components together.

[0008] However, with conventional stretch-release tapes, the stretched portion of the tape may be re-applied to an adherend from which it was previously peeled during the stretching process. The tape must be stretched again to be removed from the re-applied adherend, but this further stretches the already stretched tape, which can result in tape breakage or adhesive residue on the adherend. This phenomenon is not limited to temporary fixing applications, but can also occur when the tape is peeled from components bonded with the adhesive tape for repair, replacement, inspection, recycling, etc.

[0009] Furthermore, the inventors have found that when the adherend is a microcomponent such as an MLCC, if the microcomponent is temporarily fixed to one side of a stretch-release tape and the tape is stretched to peel it off from the microcomponent, the stretching distance of the tape (tape elongation) required to peel it off becomes excessive, which makes it more likely that the stretched portion of the tape will re-stick to the adherend.

[0010] The present disclosure has been made in view of the above-mentioned circumstances, and aims to provide a pressure-sensitive adhesive tape that has a temporary fixation property capable of holding an adherend before elongation, and that can be peeled from the adherend in a low elongation range during the stretching process and that can further inhibit re-adhesion to the adherend. The present disclosure also provides a method for manufacturing a part using the pressure-sensitive adhesive tape. [Means for solving the problem]

[0011] The present disclosure has the following aspects. [1] A pressure-sensitive adhesive tape having an extensible substrate and a pressure-sensitive adhesive layer containing a filler, wherein the filler has a solubility parameter value of 8 or more and 20 or less. [2] The adhesive tape according to [1], wherein the substrate has a breaking elongation of 200% or more. [3] The adhesive tape according to [1] or [2], wherein the filler is a filler made of a polymer material. [4] The pressure-sensitive adhesive tape according to any one of [1] to [3], wherein the content of the filler in the pressure-sensitive adhesive layer is 5% by volume or more and 75% by volume or less. [5] The pressure-sensitive adhesive tape according to any one of [1] to [4], wherein the filler has an average particle size of 0.5 μm or more and 50 μm or less. [6] Surface adhesion strength P when stretched 300% 300 is 10N / cm 2 The adhesive tape according to any one of [1] to [5] below. [7] Surface adhesive strength P when stretched 300% compared to surface adhesive strength P0 before stretching 300 Ratio of (P 300 The pressure-sensitive adhesive tape according to any one of [1] to [6], wherein P(x,y) is 0.5 or less. [8] The pressure-sensitive adhesive tape according to any one of [1] to [7], which has a 180° peel adhesive strength of 20 N / 20 mm or less. [9] A method for manufacturing a component using the adhesive tape according to any one of [1] to [8], comprising a peeling step of stretching the adhesive tape, to which one or more components are fixed, in at least one direction to peel the components from the adhesive tape.

[10] The method for manufacturing a component described in [9], wherein in the peeling step, a jig is pressed against the adhesive tape from the side opposite to the side on which the component is placed, and the adhesive tape is pushed out toward the side on which the component is placed, thereby pulling the adhesive tape.

[11] The method for manufacturing a part according to [9] or

[10] , further comprising a processing step of processing the part fixed to the adhesive tape.

[12] A method for manufacturing a part according to any one of [9] to

[11] , comprising a transfer step of fixing a transfer object to the surface of the part opposite to the surface that contacts the adhesive tape, and stretching the adhesive tape to transfer the part to the transfer object.

[13] The surface area of ​​each of the parts that is peeled off in the peeling step and that comes into contact with the adhesive tape is 1 mm 2 The method for manufacturing a component according to any one of [9] to

[12] below. [Effects of the Invention]

[0012] The adhesive tape of the present disclosure has temporary fixation properties that enable it to hold an adherend before being stretched, and during the stretching process, it can be peeled from the adherend in a low elongation range and can be prevented from being re-attached to the adherend after being peeled off. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a process diagram illustrating an example of a method for manufacturing a component according to the present disclosure. [Figure 2] FIG. 10 is a process diagram illustrating another example of a method for manufacturing a component according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0014] As used herein, the terms "extend", "stretch", "extensibility" and "stretchability" refer to the act of extending (stretching) when tension is applied by, for example, pulling, and the property thereof.

[0015] As used herein, "low elongation" refers to a low elongation percentage (elongation), which is the ratio of the difference in the length of the tape before and after stretching to the length of the tape before stretching, when the tape is stretched (elongated). Furthermore, a "low elongation region" refers to a region in which the elongation percentage is low compared to the length of the tape before stretching, i.e., a region in the initial stage of tape stretching. Specifically, a region in which the elongation of the tape is 300% or less can be considered a low elongation region. Of these, a region in which the elongation of the tape is 200% or less, particularly 150% or less, is preferred. The lower limit of the elongation of the low elongation region is not particularly limited as long as it is greater than 0%, and can be, for example, 5% or more, 10% or more, 30% or more, 50% or more, or 100% or more. The elongation of the tape when it is stretched by pulling and peeled (when the tape is stretched) is a value determined by the following formula, unless otherwise specified: Tape elongation [%] = {(length of tape after elongation) - length of tape before elongation)} / (length of tape before elongation)

[0016] In this specification, the "surface area of ​​the side of the adherend (component) that comes into contact with the tape (hereinafter sometimes referred to as the tape-side surface area)" refers to the area of ​​the surface of the adherend (component) that faces the adhesive layer when one adherend (component) is placed and fixed on the tape before stretching. Furthermore, the "adhesion area (contact area)" of the adherend (component) refers to the area of ​​the region of the surface area of ​​the adherend (component) that comes into contact with the tape that is actually adhered to the adhesive layer. Before the tape is stretched, the surface area of ​​the adherend (component) that comes into contact with the adhesive tape and the adhesion area are approximately the same. However, when the tape is stretched, portions of the tape peel off from the adherend (component), reducing the contact area, resulting in a relationship of "contact area < surface area of ​​the adherend (component) that comes into contact with the tape."

[0017] In this specification, "micro size" refers to a size of millimeter level or less, and particularly refers to a size from millimeter level to micro level. Also, "micro component" refers to a component of the adherend that is millimeter level or less, and particularly refers to a component of millimeter size to micro size. More specifically, "micro size" or "micro component" refers to a size that includes or has the dimensional size specified in JIS C 5101-22:2014 (IEC60384-22:2011). In particular, a micro component is a component having a surface area of ​​50 mm2 or less that comes into contact with the tape of the present disclosure. 2 Preferably, it is less than 30 mm 2 Preferably, it is less than 10 mm 2 Preferably less than 3 mm 2 Preferably, it is less than 1 mm 2 It is preferable that it is less than 0.5 mm. 2 Less than 0.2mm is preferable. 2 The lower limit of the surface area is not particularly limited, but is, for example, 0.001 mm 2 More than 0.01 mm, preferably 0.01 mm 2 It can be more than that.

[0018] The adhesive tape of the present disclosure and the method for manufacturing a part using the same will be described below.

[0019] I. Adhesive tape The pressure-sensitive adhesive tape of the present disclosure has an extensible substrate and a pressure-sensitive adhesive layer containing a filler, and the filler has a solubility parameter (SP) value of 8 or more and 20 or less. In the following description, the pressure-sensitive adhesive tape of the present disclosure may be referred to as the tape (of the present disclosure) or "the pressure-sensitive adhesive tape." Furthermore, a filler having a solubility parameter value within a predetermined range may be referred to as Filler A.

[0020] In conventional stretch-releasable adhesive tapes, a technique for incorporating a filler into the adhesive layer is known for the purpose of improving stretch-releasability. According to this technique, when the adhesive layer contains a filler, as the adhesive layer is stretched and thinned during the tape stretching process (stretching process), the filler protrudes from the surface of the adhesive layer and peels (detaches) from the adhesive layer. This roughens the surface of the adhesive layer, reducing the adhesive area with the adherend and facilitating peeling. However, with conventional tapes, when the stress of stretching the tape is released after stretching and peeling it from the adherend, the adhesive strength of the stretched portion is restored, which can lead to re-application to the adherend, resulting in poor workability. This is thought to be because the tape attempts to recover from the stretched and deformed state, causing the filler that had detached from the adhesive layer to be re-embedded in the adhesive layer, i.e., the rough surface of the adhesive layer disappears. Furthermore, when the adherend is a micro-component such as an MLCC, the stretching distance (elongation) required for the tape to peel off from the micro-component becomes excessive, making the stretched portion of the tape more likely to be reattached to the micro-component.

[0021] In contrast, the adhesive tape of the present disclosure contains a filler A whose adhesive layer exhibits a solubility parameter within a predetermined range, resulting in high affinity between the filler A and the base polymer contained in the adhesive layer, and excellent adhesion between the filler A and the base polymer. As a result, even when the adhesive layer of the adhesive tape of the present disclosure becomes thinner during stretching, the filler A is retained in the adhesive layer and is less likely to peel or detach from the adhesive layer. This makes it easier to cause plastic deformation of the base polymer and maintain the roughened surface of the adhesive layer formed by the protrusion of the filler A. Furthermore, in the adhesive tape of the present disclosure, even when the stress applied to stretching the tape is released, the plastic deformation of the base polymer inhibits strain recovery. This allows the roughened surface of the adhesive layer to be maintained, and the surface adhesive strength of the stretched portion can be maintained at a reduced level, thereby preventing re-application to the adherend after peeling.

[0022] Furthermore, the pressure-sensitive adhesive tape of the present disclosure can greatly reduce the surface adhesive strength with respect to elongation by having a pressure-sensitive adhesive layer containing Filler A that exhibits a solubility parameter within a predetermined range. As a result, even when the adherend is a microcomponent such as an MLCC, the pressure-sensitive adhesive tape of the present disclosure can be peeled from the microcomponent in a low elongation range.

[0023] Thus, the pressure-sensitive adhesive tape of the present disclosure has a temporary fixation property that enables it to hold an adherend before being stretched, and on the other hand, during the stretching process, it can be peeled from the adherend in a low elongation range and further can prevent re-adhesion to the peeled adherend. Note that, since the pressure-sensitive adhesive tape of the present disclosure can exhibit the above-mentioned functions, particularly good releasability and the function of preventing re-adhesion in a low elongation range, it is not limited to temporary fixing applications or process applications, and is also useful as a conventional tape for fixing components by adjusting the adhesive strength before being stretched.

[0024] The tape of the present disclosure can exert the above-mentioned effects on various adherends, especially on small parts, but it is particularly effective on parts with a surface area of ​​1 mm 2 The adhesive tape of the present disclosure is particularly effective for the following small components.

[0025] 1. Base material The substrate in the present disclosure has extensibility. The term "extensible" for a substrate means that the substrate stretches (stretches) when tension is applied to the substrate, for example, by pulling. In other words, the substrate can be stretched. The substrate needs to be extensible in at least one direction, and it is preferable that the substrate has extensibility (stretchability) in all directions within the plane of the substrate. The substrate needs to stretch when tension is applied, and does not need to restore its original shape when tension is released, but may have the elasticity to shrink in an attempt to restore its original shape.

[0026] The breaking elongation of the substrate can be, for example, 200% or more from the viewpoint of exhibiting extensibility. The breaking elongation of the substrate is preferably within a range that achieves both moderate extensibility and workability, allowing the tape to be stretched and components to be easily peeled off. For example, it can be 200% or more and 1000% or less, with 250% or more and 800% or less being preferred, 300% or more and 600% or less being more preferred, and 350% or more and 600% or less being even more preferred. By having the breaking elongation of the substrate within the above-mentioned range, the tape of the present disclosure is less likely to break during stretching and can be stretched to a desired distance. Furthermore, the stretching distance (peel elongation) of the tape of the present disclosure until the adhesive state between the tape and the adherend is released is not too long, allowing work to be done in a small space.

[0027] The breaking strength of the substrate is preferably within a range that achieves both appropriate extensibility and workability, allowing the tape to be stretched and the adherend (component) to be easily peeled off, and is, for example, preferably 30 MPa to 180 MPa, more preferably 40 MPa to 150 MPa, and even more preferably 50 MPa to 120 MPa. When the breaking strength of the substrate is within the above range, the tape of the present disclosure is less likely to tear during stretching, and the stress required to stretch the tape is not too great, allowing the temporarily fixed adherend (component) to be easily peeled off.

[0028] The breaking elongation and breaking strength of the substrate can be adjusted by appropriately selecting the type and content of the resin constituting the main component of the substrate. In addition, a method such as stretching can be used in the manufacturing process of the substrate.

[0029] The breaking elongation and breaking strength of the substrate are values ​​measured by the measuring method for [breaking strength and breaking elongation] described in the examples below.

[0030] The 100% modulus of the substrate is preferably 3 MPa or more and 30 MPa or less, more preferably 4 MPa or more and 20 MPa or less, even more preferably 5 MPa or more and 15 MPa or less, and particularly preferably 6 MPa or more and 10 MPa or less. The 300% modulus of the substrate is preferably 3.5 MPa or more and 50 MPa or less, more preferably 4 MPa or more and 40 MPa or less, even more preferably 5 MPa or more and 35 MPa or less, and particularly preferably 6 MPa or more and 30 MPa or less. By independently setting the 100% modulus and 300% modulus of the substrate within the above ranges, the tape of the present disclosure can be stretched with a relatively small force in the initial stage of elongation, while reducing the stress required for the tape to be stretched and peeled from the adherend. This facilitates the peeling operation of the tape even when the adherend is very small. Furthermore, when the tape of the present disclosure is stretched, it is easily peeled from the adherend at a relatively low elongation. If the modulus of the substrate is too low, the area other than the adhesive area between the tape and the adherend (non-adhesive area) will stretch preferentially, making it difficult for the tape to peel from the adherend.

[0031] The 100% modulus and 300% modulus of the substrate can be adjusted by, for example, appropriately selecting the composition of the substrate, the type and content of the resin constituting the main component of the substrate, the thickness of the substrate, etc. In addition, a method such as uniaxial or biaxial stretching can be used in the manufacturing process of the substrate.

[0032] The 100% modulus of the substrate is a value measured by the method for measuring the 100% modulus described in the Examples below. The 300% modulus of the substrate is measured in the same manner as the method for measuring the 100% modulus described in the Examples, and is the stress value when the gauge length is four times the initial length (when the elongation calculated by the following formula is 300%). Modulus elongation (%) = {(gauge length after elongation) - (gauge length before elongation)} / (gauge length before elongation)

[0033] The average thickness of the substrate is not particularly limited, but can be, for example, from 5 μm to 500 μm, preferably from 10 μm to 250 μm, more preferably from 25 μm to 200 μm, and even more preferably from 40 μm to 150 μm. By setting the thickness of the substrate within the above range, the strength of the tape of the present disclosure is obtained, and it can be easily stretched with a small force, improving the releasability of the adherend (component) fixed to the tape.

[0034] The average thickness of the substrate is a value measured by the method for measuring [average thickness] described in the examples below.

[0035] The hardness of the substrate is not particularly limited as long as it does not impair the functionality of the tape of the present disclosure, but is preferably a Shore hardness of at least 70 on the Shore A (Type A) scale and at most 90 on the Shore D (Type D) scale, more preferably at least 80 on the Shore A (Type A) scale and at most 80 on the Shore D (Type D) scale, and even more preferably at least 85 on the Shore A (Type A) scale and at most 70 on the Shore D (Type D) scale. Having the Shore hardness of the substrate within the above range ensures the mechanical strength and extensibility of the tape, improving workability. Furthermore, strong stress acts on the elongation behavior of the tape when the tape is stretched and peeled off from the adherend, making it easier to peel the pressure-sensitive adhesive layer from the adherend.

[0036] The hardness of the substrate is a Shore hardness, and is a value of Type A hardness or Type D hardness measured in accordance with JIS K 6253 using a durometer (spring type rubber hardness tester, model: GS-719G, manufactured by Teclock Corporation) or a durometer (spring type rubber hardness tester, model: GS-720G, manufactured by Teclock Corporation).

[0037] The substrate may be a single layer or may have a multilayer structure consisting of two or more layers, as long as it has the desired physical properties. When the substrate has a multilayer structure, the physical properties and average thickness of the substrate refer to the physical properties and average thickness of the multilayer structure.

[0038] <Resin> The substrate may be a resin film containing a resin as a main component. The main component refers to the component contained in the largest amount in the total amount of the substrate. Specifically, the content of the resin in the substrate is preferably 50% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more, even more preferably 95% by mass or more, and particularly preferably substantially 100% by mass of the total amount of the substrate.

[0039] Examples of resins constituting the substrate (resin film) include styrene-based resins, urethane-based resins, olefin-based resins, ester-based resins, acrylic-based resins, polycarbonate-based resins, polymethylpentene resins, polysulfone resins, polyetheretherketone, polyethersulfone, polyetherimide, polyimide, fluororesin, and nylon. These resins may be used alone or in combination of two or more. Among these, it is preferred that the substrate contains, as its main component, a resin selected from the group consisting of styrene-based resins, urethane-based resins, and acrylic-based resins. That is, it is preferred that the substrate be selected from the group consisting of styrene-based resin films, urethane-based resin films, and acrylic-based resin films. These resins make it easy to adjust the breaking strength and breaking elongation of the substrate to fall within the preferred ranges described above.

[0040] (styrene resin) The styrene-based resin has at least a structural unit derived from an aromatic vinyl compound. Examples of aromatic vinyl compounds that constitute structural units derived from aromatic vinyl compounds include styrene, α-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-propylstyrene, 4-t-butylstyrene, 4-cyclohexylstyrene, 4-dodecylstyrene, 2,4-dimethylstyrene, 2,4-diisopropylstyrene, 2,4,6-trimethylstyrene, 2-ethyl-4-benzylstyrene, 4-(phenylbutyl)styrene, 1-vinylnaphthalene, 2-vinylnaphthalene, vinylanthracene, N,N-diethyl-4-aminoethylstyrene, vinylpyridine, 4-methoxystyrene, monochlorostyrene, dichlorostyrene, divinylbenzene, 1,1-diphenylethylene, N,N-dimethyl-p-aminoethylstyrene, and N,N-diethyl-p-aminoethylstyrene. The above aromatic vinyl compounds may be used alone or in combination of two or more.

[0041] Among these, the styrene-based resin preferably has a structural unit derived from an aromatic vinyl compound selected from styrene, α-methylstyrene, and 4-methylstyrene, and more preferably has a structural unit derived from styrene represented by the following chemical formula (I).

[0042] [ka]

[0043] The proportion of the styrene-derived structural units in the styrene-based resin is preferably 5% by mass or more and 75% by mass or less, more preferably 10% by mass or more and 50% by mass or less, still more preferably 15% by mass or more and 45% by mass or less, and particularly preferably 20% by mass or more and 40% by mass or less, based on the total mass (100% by mass) of the styrene-based resin. By setting the proportion of the styrene-derived structural units within the above range, the breaking elongation and breaking strength of the substrate can be easily obtained within suitable ranges.

[0044] The styrene-based resin may have a single structure, such as a linear structure, a branched structure, or a multi-branched structure, or may have two or more different structures. A styrene-based resin rich in linear structures can impart excellent elongation at break to a substrate. On the other hand, a branched or multi-branched structure in which styrene blocks are arranged at the molecular terminals can form a pseudo-crosslinked structure and impart excellent cohesive strength.

[0045] Among the above styrene-based resins, block copolymers are preferred because they can reduce the elastic modulus of the substrate in the low elongation range during the process of stretching the tape, resulting in a substrate with high strength and excellent elongation at break. The above styrene-based resin may be composed of one type of block copolymer or a mixture of two or more types of block copolymers.

[0046] The styrene-based resin is preferably a vinyl aromatic block copolymer having structural units derived from the aromatic vinyl compound and structural units derived from a conjugated diene compound. The conjugated diene compound is a diolefin having a conjugated double bond, and examples thereof include conjugated diene compounds having 4 to 20 carbon atoms, preferably 4 to 10 carbon atoms, and more preferably 4 to 8 carbon atoms. Examples of the conjugated diene compound include 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 2-phenyl-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 3-methyl-1,3-pentadiene, 2,3-dimethyl-1,3-pentadiene, 4-methyl-1,3-pentadiene, 1,3-hexadiene, 2,4-hexadiene, 1,3-octadiene, 1,3-cyclohexadiene, and 2-methyl-1,3-octadiene. butadiene, 1,3,7-octatriene, 1,3-cyclopentadiene, 2-phenyl-1,3-butadiene, 2-phenyl-1,3-pentadiene, 3-phenyl-1,3-pentadiene, 2-hexyl-1,3-butadiene, 1,3-hexadiene, 1,3-cyclohexadiene, 3-methyl-1,3-hexadiene, 2-benzyl-1,3-butadiene, 2-p-tolyl-1,3-butadiene, myrcene, farnesene, and chloroprene.

[0047] Examples of the styrene resin that is the vinyl aromatic block copolymer include styrene-isoprene block copolymer, styrene-isoprene-styrene block copolymer, styrene-isoprene-butadiene-styrene block copolymer, styrene-butadiene-styrene block copolymer, styrene-ethylene-butylene block copolymer, styrene-ethylene-propylene block copolymer, and hydrogenated products of these copolymers, which may be used alone or in combination of two or more.

[0048] Examples of methods for producing the vinyl aromatic block copolymer include a method of sequentially polymerizing a block of an aromatic vinyl compound and a block of a conjugated diene compound by an anionic living polymerization method, a method of producing a block copolymer having a living active end and then reacting it with a coupling agent to produce a coupled block copolymer, etc. As a method for producing a mixture of a triblock copolymer and a diblock copolymer of a vinyl aromatic block copolymer of an aromatic vinyl compound and a conjugated diene compound, it is also possible to produce them as a mixture simultaneously in a single polymerization step.

[0049] The styrene-based block copolymer may be a hydrogenated styrene-based block copolymer. A hydrogenated styrene-based block copolymer refers to a copolymer in which the double bonds in the main chain of the styrene-based block copolymer are hydrogenated. In particular, the hydrogenated styrene-based block copolymer preferably has a random block structure of structural units derived from a conjugated diene compound, which is composed of linear hydrocarbon structural units and branched hydrocarbon structural units. The structural units derived from a conjugated diene compound having the random block structure have linear structural units that contribute to crystallinity and branched structural units that contribute to extensibility present randomly, which makes it easier to achieve both improved extensibility and breaking strength of the tape.

[0050] Examples of the hydrogenated styrene-based block copolymer include hydrogenated products of the block copolymers listed above as specific examples of the styrene-based block copolymer. Specific examples include styrene-ethylene / butylene-styrene block copolymer (SEBS) and styrene-ethylene-ethylene / propylene-styrene block copolymer (SEEPS). The styrene-ethylene-ethylene / propylene-styrene block copolymer is a hydrogenated product of a block copolymer formed from styrene-butadiene-isoprene-styrene. The styrene-ethylene / butylene-styrene block copolymer is a hydrogenated product of a styrene-isoprene / butadiene-styrene block copolymer. Among these, the hydrogenated product of a styrene-isoprene-butadiene-styrene block copolymer is particularly preferred.

[0051] The content of the styrene resin in the resin constituting the substrate is preferably 50% by mass or more, more preferably 80% by mass or more, more preferably 90% by mass or more, and particularly preferably substantially 100% by mass, based on 100% by mass of the total amount of resin in the substrate. Of these, it is more preferable that the content of the styrene block copolymer in the resin constituting the substrate is in the above range, because this allows the elastic modulus of the substrate in the low elongation range to be lowered during the tape stretching process, resulting in a substrate with high strength and excellent elongation at break.

[0052] Styrenic resins can be produced using known methods. For example, known methods can be used to produce styrenic block copolymers, such as a method of sequentially polymerizing blocks by anionic living polymerization, or a method of producing a block copolymer having a living active end and then reacting it with a coupling agent to produce a coupled block copolymer. Furthermore, when the styrenic resin is a mixture of two or more types of styrenic block copolymers, they may be produced as a mixture simultaneously in a single polymerization step.

[0053] (urethane resin) As the urethane-based resin, a reaction product of polyol and polyisocyanate can be suitably used. Specific examples of the reaction product include ester-based polyurethane and ether-based polyurethane. The urethane-based resin may be used alone or in combination of two or more.

[0054] The polyol for forming the polyol-derived structural unit can be appropriately selected depending on the purpose, and examples thereof include polyester polyol, polyether polyol, polycarbonate polyol, and acrylic polyol. One type of polyol may be used, or two or more types may be used in combination. Among them, polyester polyol or polyether polyol is preferred from the viewpoint of obtaining the mechanical properties of the substrate. From the viewpoint of heat resistance, polyester polyol is preferred, and from the viewpoint of water resistance and biodegradability, polyether polyol is preferred.

[0055] Examples of the polyester polyols include polyesters obtained by esterifying a low-molecular-weight polyol with a polycarboxylic acid, polyesters obtained by ring-opening polymerization of a cyclic ester compound such as ε-caprolactone, and copolymerized polyesters thereof. Examples of the low-molecular-weight polyols include aliphatic alkylene glycols such as ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, neopentyl glycol, and 1,3-butanediol, and cyclohexanedimethanol, all of which have a weight-average molecular weight (Mw) of approximately 60 to 280. Examples of the polycarboxylic acids include aliphatic dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, and dodecanedicarboxylic acid; aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, phthalic acid, and naphthalenedicarboxylic acid; and anhydrides or esters thereof.

[0056] Examples of the polyether polyol include those obtained by addition polymerization of alkylene oxide using one or more compounds having two or more active hydrogen atoms as an initiator.

[0057] Examples of the polycarbonate polyol include polycarbonate polyols obtained by reacting a carbonate ester and / or phosgene with a low molecular weight polyol. Examples of the carbonate ester include methyl carbonate, dimethyl carbonate, ethyl carbonate, diethyl carbonate, cyclocarbonate, and diphenyl carbonate. Examples of the low molecular weight polyol include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,2-propanediol, 1,3-propanediol, dipropylene glycol, tripropylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentanediol, 1,5-hexanediol, 1,6-hexanediol, 2,5-hexanediol, 1,7-heptanediol, and 1,8-octanediol. Examples of suitable solvents include ethanol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 2-methyl-1,3-propanediol, neopentyl glycol, 2-butyl-2-ethyl-1,3-propanediol, 3-methyl-1,5-pentanediol, 2-ethyl-1,3-hexanediol, 2-methyl-1,8-octanediol, 1,4-cyclohexanedimethanol, hydroquinone, resorcinol, bisphenol A, bisphenol F, and 4,4'-biphenol.

[0058] The polyisocyanate for forming the polyisocyanate-derived structural unit can be appropriately selected depending on the purpose, and examples thereof include alicyclic polyisocyanates, aliphatic polyisocyanates, aromatic polyisocyanates, and modified products of these polyisocyanates (adducts, biuret products, allophanate-type modified products, isocyanurate-type modified products, and reaction products having an isocyanate group and a urethane bond obtained by reacting an isocyanate with a polyol under conditions of excess isocyanate groups). One type of polyisocyanate may be used, or two or more types may be used in combination. Among these, alicyclic polyisocyanates and / or modified products thereof are preferred.

[0059] Examples of the alicyclic polyisocyanate include isophorone diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, 4,4'-dicyclohexylmethane diisocyanate, 2,4-methylcyclohexane diisocyanate, 2,6-methylcyclohexane diisocyanate, cyclohexylene diisocyanate, methylcyclohexylene diisocyanate, bis(2-isocyanatoethyl)-4-cyclohexylene-1,2-dicarboxylate, 2,5-norbornane diisocyanate, 2,6-norbornane diisocyanate, dimer acid diisocyanate, bicycloheptane triisocyanate, etc. One type of alicyclic polyisocyanate may be used, or two or more types may be used in combination.

[0060] In the urethane resin, the equivalent ratio (NCO / OH equivalent ratio) of the isocyanate group (NCO) of the polyisocyanate to the hydroxyl group (OH) of the polyol is preferably in the range of 1 to 20, more preferably in the range of 1.1 to 13, even more preferably in the range of 1.2 to 5, and particularly preferably in the range of 1.5 to 3.

[0061] The softening point of the urethane resin is preferably 45° C. or higher, more preferably 55° C. or higher. There is no particular upper limit to the softening point, but it is preferably 110° C. or lower. In this specification, the "softening point" refers to a value measured in accordance with JIS K 2207 (ring and ball method).

[0062] The urethane resin may be a thermoplastic polyurethane. The thermoplastic polyurethane may be appropriately selected within a range that does not impair the effects of the present invention, and examples thereof include block copolymers containing hard segments and soft segments, known as TPU. More specifically, examples thereof include polyester-based TPU, polyether-based TPU, and polycarbonate-based TPU.

[0063] (acrylic resin) The acrylic resin may be an acrylic random polymer or an acrylic block polymer. Among these, it is preferable to include an acrylic block polymer, since this allows for easy adjustment of the mechanical properties of the substrate. The acrylic block copolymer may be a diblock copolymer, a triblock copolymer, or a tetrablock or higher block copolymer, but an acrylic triblock copolymer is preferred because it can achieve both excellent breaking strength and extensibility due to its excellent cohesive force. The acrylic polymer may contain two or more acrylic block copolymers with different block structures.

[0064] The acrylic block copolymer preferably comprises a polymer block having structural units derived from an alkyl methacrylate ester and a polymer block having structural units derived from an alkyl acrylate ester, and more preferably comprises a midblock phase having structural units derived from an alkyl acrylate ester, and endblock phases located on both sides of the midblock phase each independently having a structural unit derived from an alkyl methacrylate ester. It is also preferred that the polymer block having the structural unit derived from an alkyl acrylate ester is a soft block, and the polymer block having the structural unit derived from an alkyl methacrylate ester is a hard block.

[0065] The structural unit derived from a methacrylic acid alkyl ester monomer refers to a structural unit derived from a methacrylic acid alkyl ester monomer when the methacrylic acid alkyl ester is (co)polymerized or graft polymerized, i.e., a repeating unit derived from a methacrylic acid ester monomer. Examples of the methacrylic acid alkyl ester monomer include methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, sec-butyl methacrylate, t-butyl methacrylate, n-pentyl methacrylate, isopentyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, pentadecyl methacrylate, cyclohexyl methacrylate, lauryl methacrylate, tridecyl methacrylate, and 2-hexyldecyl methacrylate. Of these, methyl methacrylate is preferred.

[0066] The structural unit derived from an acrylate alkyl ester refers to a constituent unit derived from an acrylate alkyl ester monomer when the acrylate alkyl ester monomer is (co)polymerized or graft polymerized, i.e., a repeating unit derived from an acrylate ester monomer. Examples of the acrylate alkyl ester monomer unit include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, sec-butyl acrylate, t-butyl acrylate, amyl acrylate, isoamyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, and lauryl acrylate. Among these, n-butyl acrylate, 2-ethylhexyl acrylate, and copolymers thereof are preferred from the viewpoint of imparting extensibility to the substrate.

[0067] In the above alkyl methacrylates and alkyl acrylates, one or more hydrogen atoms in the alkyl group may be substituted with, for example, a halogen atom, an amino group, a cyano group, or the like.

[0068] When the degree of polymerization of the structural unit derived from an alkyl acrylate is q and the degrees of polymerization of the structural units derived from an alkyl methacrylate located on both sides of the polymer block of the structural unit derived from an alkyl acrylate are p and r, respectively, p / (p+q+r) is preferably 0.02 to 0.40, more preferably 0.05 to 0.37. q / (p+q+r) is preferably 0.20 to 0.95, more preferably 0.25 to 0.90. r / (p+q+r) is preferably 0.02 to 0.40, more preferably 0.05 to 0.37. The values ​​of p, q, and r are related to molecular weight, etc.

[0069] Preferred forms of the acrylic triblock copolymer include polymethyl methacrylate block-polyn-butyl acrylate block-polymethyl methacrylate block, polyethyl methacrylate block-polyn-butyl acrylate block-polyethyl methacrylate block, polypropyl methacrylate block-polyn-butyl acrylate block-polypropyl methacrylate block, polymethyl methacrylate block-polyt-butyl acrylate block-polymethyl methacrylate block, and polymethyl methacrylate block-polypropyl acrylate block-polymethyl methacrylate block.

[0070] The acrylic block copolymer may contain one or more triblock copolymers or diblock copolymers, or may be a mixture of one or more triblock copolymers and one or more diblock copolymers. The content of the diblock copolymer in the mixture can be appropriately selected depending on the purpose.

[0071] The acrylic block copolymer may be modified, if necessary, with a functional group such as a hydroxyl group, a carboxyl group, an acid anhydride group, an amino group, or a trimethoxysilyl group in the molecular side chain or at the molecular main chain terminal.

[0072] The weight-average molecular weight (hereinafter also referred to as "Mw") of the acrylic block copolymer is preferably from 50,000 to 300,000, more preferably from 100,000 to 250,000, and even more preferably from 130,000 to 230,000. The number-average molecular weight (hereinafter also referred to as "Mn") of the acrylic block copolymer is preferably from 50,000 to 300,000, more preferably from 100,000 to 250,000, and even more preferably from 130,000 to 230,000. When the Mw and / or Mn of the acrylic block copolymer are within the above ranges, the substrate can achieve both excellent extensibility and breaking strength, and also achieve good thickness uniformity. If the Mw and Mn of the acrylic block copolymer are too small, it is difficult to obtain the desired extensibility and breaking strength of the substrate. On the other hand, if the Mw and Mn are too large, the acrylic block copolymer is difficult to dissolve in a solvent, making molding, such as by heat melting, difficult, and making it difficult to obtain a substrate with the desired properties. In particular, the acrylic block copolymer preferably has an Mw of 100,000 or more and an Mn of 100,000 or more and an Mn of 100,000 or more and an Mw of 130,000 or more and an Mn of 130,000 or more and an Mn of 130,000 or more and an Mn of 230,000 or more.

[0073] The Mw and Mn of the acrylic block copolymer are measured by GPC using a GPC device (HLC-8329GPC, manufactured by Tosoh Corporation). Mw and Mn are values ​​converted into standard polystyrene, and the measurement conditions by GPC are the same as those described above.

[0074] The method for producing the acrylic block copolymer can be appropriately selected from conventionally known production methods, and examples thereof include a method for sequentially polymerizing a block copolymer by an anionic living polymerization method, a cationic living polymerization method, etc. Furthermore, when the block copolymer has stereoregularity such as syndiotacticity, a known method using an organometallic complex may be used.

[0075] (others) When the resin constituting the base material is a block copolymer, the soft segment of the block copolymer preferably has a random copolymer structure of linear hydrocarbon structural units and branched hydrocarbon structural units. Having the desired structure for the soft segment in the block copolymer can further enhance stretchability (extensibility) and breaking strength. In particular, it is preferable that the block copolymer is a triblock or higher copolymer and that the soft segment has the above-mentioned specific structure. In other words, it is preferable that the block copolymer has a midblock and end blocks located on both sides of the midblock, and that the midblock has a random copolymer structure of linear hydrocarbon structural units and branched hydrocarbon structural units. The synergistic function of the hard segment (endblock) and the soft segment (midblock) can achieve both excellent cohesive strength and extensibility. Examples of such resins include hydrogenated styrene triblock copolymers, such as styrene-ethylene / butylene-styrene block copolymers (SEBS) and styrene-ethylene-ethylene / propylene-styrene block copolymers (SEEPS).

[0076] <Other ingredients> The substrate may contain other components as needed. Examples of other components include tackifier resins, crosslinkers, antioxidants, UV absorbers, fillers, polymerization inhibitors, surface conditioners, antistatic agents, antifoaming agents, viscosity modifiers, light stabilizers, weather stabilizers, heat stabilizers, antioxidants, leveling agents, organic pigments, inorganic pigments, pigment dispersants, silica beads, organic beads, and inorganic fillers. The content of other components in the substrate may be appropriately selected within a range that does not impair the properties of the substrate.

[0077] 2. Adhesive layer The PSA layer of the present disclosure contains one or more fillers (filler A) having a solubility parameter of 8 or more and 20 or less. The PSA layer is formed from a PSA composition containing the filler A and a base polymer. The PSA composition may optionally contain a tackifier resin in addition to the base polymer. The base polymer and the optional tackifier resin contribute to the adhesiveness of the PSA layer, and are therefore collectively referred to as the PSA resin. When the PSA layer contains a base polymer and an optional tackifier resin, the mixture of the base polymer and the tackifier resin is referred to as the PSA resin. The base polymer may also be crosslinked with a crosslinking agent.

[0078] (1) Filler A The filler A may have a solubility parameter of 8 or more and 20 or less, and from the viewpoint of dispersibility in the pressure-sensitive adhesive layer and adhesion, the solubility parameter is preferably 8.2 or more and 18 or less, more preferably 8.5 or more and 16 or less, even more preferably 9 or more and 15 or less, and particularly preferably 10 or more and 14 or less. When the solubility parameter (SP) of filler A is within the above range, filler A can exhibit high compatibility with the base polymer constituting the pressure-sensitive adhesive layer, and roughening of the pressure-sensitive adhesive layer surface due to protrusion of filler A as the tape is stretched can be achieved and maintained. If the compatibility between filler A and the adhesive resin in the pressure-sensitive adhesive layer is low, the protrusion of filler A that occurs on the pressure-sensitive adhesive layer surface as the tape is stretched cannot be maintained, and filler A may fall off from the pressure-sensitive adhesive layer or be re-buried in the pressure-sensitive adhesive layer, resulting in the disappearance of the unevenness of the pressure-sensitive adhesive layer surface caused by filler A. As a result, the roughness of the surface of the adhesive layer due to stretching of the tape decreases over time, and the adhesive strength to the adherend recovers, making it easier to re-attach the tape to an adherend after it has been peeled off. Meanwhile, by having the solubility parameter of Filler A within the above range, it is possible to prevent Filler A from falling off from the adhesive layer or being re-embedded in the adhesive layer during the tape stretching process. As a result, the tape of the present disclosure is prevented from decreasing the roughness of the surface of the adhesive layer over time due to stretching and from recovering the adhesive strength to the adherend, making it difficult to re-attach the tape to an adherend.

[0079] The solubility parameter is originally a parameter used to measure the solubility of a binary solution, but it has been found that the extended SP value introduced by Hansen can also be applied to additives and particle surfaces. The solubility parameter of fillers (hereinafter referred to as "SP value") can be calculated using the values ​​listed in "Plastic Solubility | Technical Information | (MISUMI-VONA (misumi-ec.com)"), "Solubility Parameters (SP Values) of Homopolymers and Resins - Plastic Materials Dictionary" (https: / / jp.misumi-ec.com / tech-info / categories / plastic_mold_design / pl09 / c0897.html), and "Optimal Design and Application Technology for Pressure Sensitive Adhesives and Adhesives" (1st edition, published June 30, 2014) published by the Technical Information Association.

[0080] An example of the filler A is an organic filler. An example of the organic filler is a filler made of a polymeric material (hereinafter also referred to as a "polymer filler"). The polymeric material is preferably a resin, and examples thereof include a thermoplastic resin, a thermosetting resin, and a rubber. Among these, the filler A is preferably a filler made of a thermoplastic resin. Examples of the thermoplastic resin include a thermoplastic plastic and a thermoplastic elastomer. Note that a filler made of a polymeric material means that the constituent material of the filler is substantially a polymeric material, but it is acceptable for the filler to contain components other than the polymeric material as long as the physical properties and functions of the filler A are not impaired.

[0081] Examples of polymeric materials that constitute the organic filler include polyolefins such as polyethylene, polypropylene, and polystyrene; polyethers such as polyoxymethylene and polyoxyethylene; halogenated polyolefins such as polyvinyl chloride and polyvinylidene chloride; polyesters such as polycarbonate, polymethylene terephthalate, polyethylene terephthalate, and polybutylene terephthalate; acrylic resins such as polyacrylonitrile; acrylate resins such as polyacrylate, polymethacrylate, polymethyl methacrylate, polyethyl acrylate, and styrene / methacrylic acid copolymer; vinyl carboxylic acid polymers and saponified products thereof such as polyvinyl acetate, ethylene-vinyl acetate copolymer, polyvinyl alcohol, and ethylene-vinyl alcohol copolymer; modified celluloses such as ethyl cellulose, cellulose acetate, and cellulose nitrate; rubbers such as butyl rubber, natural rubber, isobutylene rubber, butadiene rubber, and nitrile rubber; polyamides such as nylon 6, nylon 66, and aramid; epoxy resins such as bisphenol A epoxy resins and novolac epoxy resins; polyurethanes; polyimides; melamine resins; phenolic resins; benzoguanamine resins; and urea-formalin resins.

[0082] Among these, fillers made of at least one of polyamide and modified cellulose are preferred from the viewpoint of dispersibility in the pressure-sensitive adhesive layer and adhesion. Among polyamides, nylon (nylon 6, nylon 66) is more preferred, and among modified celluloses, cellulose acetate is more preferred, with fillers made of at least one of nylon and cellulose acetate being even more preferred.

[0083] The filler A may have a regular or irregular shape. Specific examples of the shape of the filler A include polygonal, cubic, elliptical, spherical, needle-like, flat, and scale-like shapes. Among these, the shape of the filler A is preferably elliptical, spherical, or polygonal, and more preferably spherical, because these shapes improve the sliding properties of the pressure-sensitive adhesive layer against the adherend when the tape of the present disclosure is stretched, thereby improving the releasability of the tape. Fillers having these shapes may be used alone or in combination of two or more.

[0084] The filler A may be a hollow filler having an internal void (hollow structure), a solid filler having no internal void, or a core-shell structure having a core and a shell covering the surface of the core. Among these, the filler A is preferably a hollow filler, because it can more efficiently reduce the surface adhesive force in the low elongation range when the tape of the present disclosure is stretched and can further impart a shock absorbing effect.

[0085] The average particle size of the filler A is not particularly limited, but is preferably from 0.5 μm to 50 μm, more preferably from 1 μm to 40 μm, even more preferably from 5 μm to 30 μm, and particularly preferably from 7 μm to 20 μm. When the average particle size of the filler A is within the above range, the tape before stretching has adhesive strength that enables it to stably temporarily fix an adherend (especially a micro-sized adherend), and on the other hand, during the stretching process, the roughness of the pressure-sensitive adhesive layer surface can be increased even if the stretching distance (elongation) is small, and the surface adhesive strength in the low elongation range can be significantly reduced.

[0086] The average particle size of the filler A mentioned above refers to the volume average particle size. The particle size of the filler is measured using a measuring device that uses a laser diffraction scattering method, such as a Microtrac, and a cumulative curve of the volume versus particle size is calculated, with the total volume of the filler being 100%. The particle size at the point on the cumulative curve where the cumulative volume is 50% is taken as the average particle size.

[0087] The content of filler A in the pressure-sensitive adhesive layer is preferably 5 to 75% by volume, preferably 8 to 50% by volume, preferably 10 to 45% by volume, and preferably 12 to 40% by volume, of the total amount (100% by volume) of the pressure-sensitive adhesive layer. By setting the content (volume %) of filler A in the pressure-sensitive adhesive layer within the above ranges, the tape before stretching has adhesive strength that allows it to stably temporarily fix adherends (especially micro-sized adherends), while the roughness of the pressure-sensitive adhesive layer surface can be increased during the stretching process even if the stretching distance (elongation) is small, and the surface adhesive strength in the low elongation range can be significantly reduced.

[0088] (2) Base polymer The pressure-sensitive adhesive layer contains one or more base polymers. The base polymer may be a polymer commonly used in pressure-sensitive adhesives, such as an acrylic polymer, a rubber polymer, or a urethane polymer. The pressure-sensitive adhesive composition constituting the pressure-sensitive adhesive layer may be an acrylic pressure-sensitive adhesive composition, a rubber pressure-sensitive adhesive composition, or a urethane pressure-sensitive adhesive composition, depending on the type of base polymer.

[0089] From the viewpoint of exhibiting the adhesive function of the base polymer, the content of the base polymer in the adhesive layer is preferably 20% by mass or more and 80% by mass or less, more preferably 30% by mass or more and 70% by mass or less, and even more preferably 40% by mass or more and 60% by mass or less, based on 100% by mass of the adhesive layer (solid matter of the adhesive composition).

[0090] <<Acrylic polymer>> When the pressure-sensitive adhesive layer is composed of an acrylic pressure-sensitive adhesive composition, the pressure-sensitive adhesive layer contains one or more acrylic polymers as a base polymer. The acrylic pressure-sensitive adhesive composition preferably contains 50% by mass or more of the acrylic polymer in 100 parts by mass of the base polymer, since this makes it easier to achieve both releasability and adhesive strength in the resulting tape of the present disclosure. More preferably, the proportion of the acrylic polymer in 100 parts by mass of the base polymer is 50% by mass or more, more preferably 80% by mass or more, even more preferably 90% by mass or more, and particularly preferably 100% by mass.

[0091] The acrylic polymer may be a block copolymer, a random copolymer, or a mixture of a block copolymer and a random copolymer. The acrylic polymer may also have a crosslinked structure. That is, the acrylic polymer may be a reaction product with a crosslinking agent. Among these, from the viewpoint of achieving both adhesiveness and releasability, a block copolymer is preferably used as the acrylic polymer.

[0092] (acrylic block copolymer) The acrylic block copolymer may be a diblock copolymer, a triblock copolymer, or a tetrablock or higher block copolymer. The pressure-sensitive adhesive layer may contain two or more acrylic block copolymers with different block structures. Among these, it is preferable to use at least one of an acrylic diblock copolymer and an acrylic triblock copolymer as the acrylic block copolymer. It is more preferable to use an acrylic triblock copolymer, as this copolymer provides excellent cohesive strength and excellent holding power. As the acrylic block copolymer, a triblock copolymer having a repeating unit represented by the following general formula (1) can be used.

[0093] [ka]

[0094] In the above general formula (1), A, B, and C each independently represent a repeating unit, and A and C each independently represent a methacrylic acid alkyl ester monomer unit. B represents an acrylic acid alkyl ester monomer unit. p, q, and r each independently represent the degree of polymerization of each monomer unit. A and C may be methacrylic acid alkyl ester monomer units having the same chemical structure or different chemical structures. In the above general formula (1), * represents a bond to another atom, and the same applies hereinafter.

[0095] The term "methacrylic acid alkyl ester monomer unit" refers to a structural unit derived from a methacrylic acid alkyl ester monomer when the methacrylic acid alkyl ester monomer is (co)polymerized or graft polymerized, i.e., a repeating unit derived from a methacrylic acid ester monomer. In the present disclosure, the methacrylic acid alkyl ester monomer unit is preferably a methacrylic acid alkyl ester monomer unit represented by the following general formula (2):

[0096] [ka]

[0097] In the general formula (2), R 1 represents an alkyl group having 1 to 12 carbon atoms, and one or more hydrogen atoms in the alkyl group are substituted by a substituent R 2 The substituent R 2 is, for example, a halogen atom, an amino group, or a cyano group.

[0098] In the above general formula (2), R 1 From the viewpoint of achieving both excellent adhesive strength and releasability, alkyl groups having 1 to 12 carbon atoms are preferred, and from the viewpoint of improving the cohesiveness of the substrate and increasing the breaking strength, alkyl groups having 1 to 4 carbon atoms are more preferred, and alkyl groups having 1 or 2 carbon atoms are even more preferred. In addition, in the above general formula (2), the alkyl group having 1 to 12 carbon atoms may be linear, branched, or cyclic, but from the viewpoint of adhesive strength, linear or branched groups are preferred, and linear groups are more preferred.

[0099] In the general formula (2), examples of the alkyl group having 1 to 12 carbon atoms include linear or branched alkyl groups such as methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, t-butyl, n-pentyl, isopentyl, hexyl, octyl, nonyl, decyl, undecyl, and dodecyl, as well as cyclic alkyl groups such as cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, dicyclopentanyl, and adamantyl. Among these, from the viewpoint of the removability and high load holding power of the resulting adhesive tape, methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, t-butyl, or cyclobutyl is preferred, and methyl, ethyl, and propyl are more preferred. One or more hydrogen atoms in the alkyl group may be substituted with a halogen atom, an amino group, or a cyano group.

[0100] Examples of the methacrylic acid alkyl ester monomer include methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, sec-butyl methacrylate, t-butyl methacrylate, n-pentyl methacrylate, isopentyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, pentadecyl methacrylate, cyclohexyl methacrylate, lauryl methacrylate, tridecyl methacrylate, 2-hexyldecyl methacrylate, etc. Among these, methyl methacrylate is preferred from the viewpoint of improving the releasability when the resulting pressure-sensitive adhesive tape is stretched and peeled from the adherend.

[0101] The B in the general formula (1) represents an acrylate alkyl ester monomer unit. In this specification, the term "acrylate alkyl ester monomer unit" refers to a structural unit derived from an acrylate alkyl ester monomer when the acrylate alkyl ester monomer is (co)polymerized or graft polymerized, i.e., a repeating unit derived from an acrylate ester monomer. The acrylate alkyl ester monomer unit is preferably an acrylate alkyl ester monomer unit represented by the following general formula (3):

[0102] [ka]

[0103] In the general formula (3), R 3 represents an alkyl group having 1 to 12 carbon atoms, and one or more hydrogen atoms in the alkyl group are substituted by a substituent R 4 The substituent R 4 is, for example, a halogen atom, an amino group, or a cyano group.

[0104] In the above general formula (3), R 3is more preferably an alkyl group having 1 to 12 carbon atoms, and even more preferably an alkyl group having 4 to 8 carbon atoms. In the above general formula (4), the alkyl group having 1 to 12 carbon atoms may be linear, branched, or cyclic, but is preferably linear or branched. In addition, the alkyl group having 1 to 12 carbon atoms is the same as the alkyl group exemplified in the above general formula (2).

[0105] Preferred R in the above general formula (3) 3 is a linear or branched alkyl group such as methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, t-butyl, n-pentyl, isopentyl, hexyl, octyl, nonyl, decyl, undecyl, or dodecyl, or a cyclic alkyl group such as cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, dicyclopentanyl, or adamantyl. One or more hydrogen atoms in the alkyl group may be substituted with a halogen atom, an amino group, or a cyano group.

[0106] Examples of the alkyl acrylate monomer include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, sec-butyl acrylate, t-butyl acrylate, amyl acrylate, isoamyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, etc. Among these, from the viewpoint of achieving both adhesive strength and removability of the resulting pressure-sensitive adhesive tape, n-butyl acrylate, 2-ethylhexyl acrylate, and copolymers thereof are preferred.

[0107] In the general formula (1), p, q, and r each independently represent the degree of polymerization of each monomer unit. The values ​​of p, q, and r relate to molecular weight, etc. p / (p+q+r) is preferably 0.02 to 0.40, more preferably 0.05 to 0.37. q / (p+q+r) is preferably 0.20 to 0.95, more preferably 0.25 to 0.90. r / (p+q+r) is preferably 0.02 to 0.40, more preferably 0.05 to 0.37.

[0108] The acrylic block copolymer is preferably an acrylic block copolymer having a repeating unit represented by the following general formula (4).

[0109] [ka]

[0110] In the general formula (4), R 1 and R 5 each independently represents an alkyl group having 1 to 12 carbon atoms, and one or more hydrogen atoms in the alkyl group are substituted by a substituent R 2 The substituent R 2 is, for example, a halogen atom, an amino group, or a cyano group. 3 represents an alkyl group having 1 to 12 carbon atoms, and one or more hydrogen atoms in the alkyl group are substituted by a substituent R 4 The substituent R 4 is a halogen atom, an amino group, or a cyano group.

[0111] In the above general formula (4), R 1 is R in the above general formula (2). 1 In the above general formula (4), R 3 is R in the above general formula (3). 3 In the above general formula (4), R 5 is R in the above general formula (2). 1In the general formula (4), p, q, and r are the same as p, q, and r in the general formula (1). 1 and R 5 may be the same or different.

[0112] When the triblock copolymer is represented by the general formula (4), R 1 is preferably selected from the group consisting of linear or branched alkyl groups such as methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, and t-butyl groups, and cyclobutyl groups; R 3 is preferably selected from the group consisting of methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, t-butyl, n-pentyl, isopentyl, hexyl, octyl, nonyl, decyl, or undecyl groups. 5 is preferably selected from the group consisting of linear or branched alkyl groups such as methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, and t-butyl groups, and cyclobutyl groups.

[0113] In the triblock copolymer, A and C in the general formula (1) may be the same or different, but are preferably the same. In the case of an ABA triblock copolymer in which A and C are the same, a high cohesive strength can be imparted to the resulting adhesive layer, making it easier to ensure peelability and excellent adhesive strength.

[0114] Preferred forms of the acrylic triblock copolymer include polymethyl methacrylate block-polyn-butyl acrylate block-polymethyl methacrylate block, polyethyl methacrylate block-polyn-butyl acrylate block-polyethyl methacrylate block, polypropyl methacrylate block-polyn-butyl acrylate block-polypropyl methacrylate block, polymethyl methacrylate block-polyt-butyl acrylate block-polymethyl methacrylate block, and polymethyl methacrylate block-polypropyl acrylate block-polymethyl methacrylate block.

[0115] Furthermore, as the acrylic block copolymer, a diblock copolymer having a repeating unit represented by the general formula (5) can be used.

[0116] [ka]

[0117] In the general formula (5), D and E each independently represent a repeating unit, D represents a methacrylic acid alkyl ester monomer unit, and E represents an acrylic acid alkyl ester monomer unit. s and t each independently represent the degree of polymerization of each monomer unit.

[0118] The diblock polymer is preferably a diblock polymer having a repeating unit represented by the following general formula (6).

[0119] [ka]

[0120] In the general formula (6), R 6 represents an alkyl group having 1 to 12 carbon atoms, and one or more hydrogen atoms in the alkyl group are substituted by a substituent R 8 The substituent R 8is, for example, a halogen atom, an amino group, or a cyano group. 7 represents an alkyl group having 1 to 12 carbon atoms, and one or more hydrogen atoms in the alkyl group are substituted by a substituent R 9 The substituent R 9 is, for example, a halogen atom, an amino group, or a cyano group. s and t each independently represent the degree of polymerization of each monomer unit.

[0121] In the above general formula (6), R 6 Specific functional groups represented by include R 1 In the above general formula (6), R 7 Specific functional groups represented by include R 3 is the same as the group exemplified above.

[0122] In the above general formulas (5) and (6), s and t each independently represent the degree of polymerization of each monomer unit. The values ​​of s and t relate to the molecular weight, etc. s / (s+t) is preferably 0.01 to 0.99, more preferably 0.1 to 0.9. t / (s+t) is preferably 0.01 to 0.99, more preferably 0.1 to 0.9.

[0123] The acrylic block copolymer may contain only one or more of the triblock copolymers, or may contain only one or more of the diblock copolymers. Furthermore, a mixture of the triblock copolymer and the diblock copolymer can be used as the acrylic block copolymer, and the content of the diblock copolymer in the mixture can be appropriately selected depending on the purpose. When a mixture of the triblock copolymer and the diblock copolymer is used, the content of the diblock copolymer is preferably 0 to 80 parts by mass, more preferably 0 to 50 parts by mass, even more preferably 0 to 30 parts by mass, and even more preferably 0 to 20 parts by mass, relative to 100 parts by mass of the triblock copolymer. Increasing the content of the diblock copolymer in the pressure-sensitive adhesive layer makes it easier to ensure adhesion to the adherend. On the other hand, if the content of the diblock copolymer is too high, there is an increased risk of adhesive residue when peeling from the adherend, so it is preferable to adjust the content appropriately depending on the application.

[0124] The weight-average molecular weight (hereinafter also referred to as "Mw") of the acrylic block copolymer is preferably in the range of 50,000 to 300,000, more preferably in the range of 100,000 to 250,000, and even more preferably in the range of 130,000 to 230,000. The number-average molecular weight (hereinafter also referred to as "Mn") of the acrylic block copolymer is preferably in the range of 50,000 to 300,000, more preferably in the range of 100,000 to 250,000, and even more preferably in the range of 130,000 to 230,000. It is more preferable that the Mw of the block copolymer is in the range of 100,000 to 250,000 and the Mn is in the range of 100,000 to 250,000, and even more preferably that the Mw of the block copolymer is in the range of 130,000 to 230,000 and the Mn is in the range of 130,000 to 230,000. The preferred ranges of Mw and Mn for the acrylic triblock copolymers represented by general formulas (1) and (4) and the preferred ranges of Mw and Mn for the acrylic diblock copolymers represented by general formulas (5) and (6) are the same as the above ranges.

[0125] The Mw and / or Mn of the acrylic block copolymer are preferably within the above ranges from the viewpoint of releasability, and it is particularly preferred that both Mw and Mn satisfy the above ranges at the same time, since better releasability can be obtained.

[0126] The Mw and Mn of the acrylic block copolymer are measured by the GPC method using a GPC device (HLC-8329GPC, manufactured by Tosoh Corporation). Mw and Mn are values ​​converted into standard polystyrene, and the measurement conditions by the GPC method are as follows: [Measurement conditions] Sample concentration: 0.5% by mass (tetrahydrofuran (THF) solution) Sample injection volume: 100 μL · Eluent: THF · Flow rate: 1.0mL / min · Measurement temperature: 40℃ Column: TSKgel GMHHR-H(20) x 2 Guard column: TSKgel HXL-H Detector: Differential refractometer Standard polystyrene molecular weight: 10,000 to 20 million (Tosoh Corporation)

[0127] Preferred forms of the triblock copolymer include polymethyl methacrylate block-polyn-butyl acrylate block-polymethyl methacrylate, polyethyl methacrylate block-polyn-butyl acrylate block-polyethyl methacrylate, polypropyl methacrylate block-polyn-butyl acrylate block-polypropyl methacrylate, polymethyl methacrylate block-polyt-butyl acrylate block-polymethyl methacrylate, and polymethyl methacrylate block-polypropyl acrylate block-polymethyl methacrylate.

[0128] The acrylic block copolymer may be modified, if necessary, with a functional group such as a hydroxyl group, a carboxyl group, an acid anhydride group, an amino group, or a trimethoxysilyl group in the molecular side chain or at the molecular main chain terminal.

[0129] The method for producing the block copolymer can be appropriately selected from conventionally known production methods, and examples thereof include a method for sequentially polymerizing a block copolymer by an anionic living polymerization method, a cationic living polymerization method, etc. Furthermore, when the block copolymer has stereoregularity such as syndiotacticity, a known method using an organometallic complex may be used.

[0130] (acrylic random copolymer) The acrylic random copolymer can be produced, for example, by polymerizing a (meth)acrylate monomer. In this specification, "(meth)acrylate" refers collectively to acrylate and methacrylate. Similarly, "(meth)acryloyl" refers collectively to acryloyl and methacryloyl, and "(meth)acrylic" refers collectively to acrylic and methacrylic. As the (meth)acrylate monomer, for example, alkyl(meth)acrylate having an alkyl group having 1 to 12 carbon atoms can be used.

[0131] Specific examples of alkyl (meth)acrylates having an alkyl group having 1 to 12 carbon atoms include methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, n-hexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, etc. These may be used alone or in combination of two or more.

[0132] As the alkyl(meth)acrylate having an alkyl group with 1 to 12 carbon atoms, it is preferable to use an alkyl(meth)acrylate having an alkyl group with 4 to 12 carbon atoms, it is more preferable to use an alkyl(meth)acrylate having an alkyl group with 4 to 8 carbon atoms, and it is particularly preferable to use n-butyl acrylate in order to ensure excellent adhesion to the adherend.

[0133] The alkyl (meth)acrylate having an alkyl group having 1 to 12 carbon atoms is preferably used in a range of 80% by mass to 98.5% by mass, more preferably 90% by mass to 98.5% by mass, based on the total amount of monomers (structural units of the acrylic random copolymer) used in producing the acrylic random copolymer.

[0134] Other monomers that can be used to produce acrylic random copolymers include highly polar vinyl monomers, if necessary. Examples of highly polar vinyl monomers include (meth)acrylic monomers such as (meth)acrylic monomers having a hydroxyl group, (meth)acrylic monomers having a carboxyl group, and (meth)acrylic monomers having an amide group, as well as sulfonic acid group-containing monomers such as vinyl acetate, ethylene oxide-modified succinic acid acrylate, and 2-acrylamido-2-methylpropanesulfonic acid. These may be used alone or in combination of two or more.

[0135] Specific examples of the (meth)acrylic monomer having a hydroxyl group include (meth)acrylic monomers such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and 6-hydroxyhexyl (meth)acrylate.

[0136] Among these, it is preferable that the monomers constituting the acrylic random copolymer contain a vinyl monomer having a hydroxyl group, since this makes it possible to form a crosslinked structure by reaction with a crosslinking agent. The vinyl monomer having a hydroxyl group is preferably used in an amount within a range of 0.01% by mass to 1.0% by mass, more preferably 0.03% by mass to 0.3% by mass, based on the total amount of monomers used in producing the acrylic random copolymer.

[0137] Specific examples of highly polar vinyl monomers having a carboxyl group include (meth)acrylic monomers such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, (meth)acrylic acid dimer, crotonic acid, and ethylene oxide-modified succinic acid acrylate. Among these, acrylic acid is preferred.

[0138] Specific examples of highly polar vinyl monomers having an amide group include (meth)acrylic monomers such as N-vinylpyrrolidone, N-vinylcaprolactam, acryloylmorpholine, acrylamide, and N,N-dimethylacrylamide.

[0139] In addition to the vinyl monomers mentioned above, the highly polar vinyl monomer may also be a sulfonic acid group-containing monomer such as vinyl acetate, ethylene oxide-modified succinic acid acrylate, or 2-acrylamido-2-methylpropanesulfonic acid.

[0140] The highly polar vinyl monomer is preferably used in a range of 1.5% by mass to 20% by mass, more preferably 1.5% by mass to 10% by mass, relative to the total amount of monomers used in producing the acrylic random copolymer, and even more preferably in a range of 2% by mass to 8% by mass, since this allows for the formation of an adhesive layer that is balanced in terms of cohesion, holding power, and adhesiveness.

[0141] The method for producing the acrylic random polymer can be appropriately selected from known methods depending on the purpose. For example, a method of polymerizing a monomer by a polymerization method such as a solution polymerization method, a bulk polymerization method, a suspension polymerization method, or an emulsion polymerization method can be mentioned. Among these, the acrylic random polymer is preferably produced by a solution polymerization method or a bulk polymerization method.

[0142] During polymerization, if necessary, a peroxide-based thermal polymerization initiator such as benzoyl peroxide or lauroyl peroxide, an azo thermal polymerization initiator such as azobisisobutylnitrile, an acetophenone-based photopolymerization initiator, a benzoin ether-based photopolymerization initiator, a benzyl ketal-based photopolymerization initiator, an acylphosphine oxide-based photopolymerization initiator, a benzoin-based photopolymerization initiator, or a benzophenone-based photopolymerization initiator can be used.

[0143] The Mw of the acrylic random copolymer obtained by the above method is preferably 300,000 to 3,000,000, more preferably 500,000 to 2,500,000. The Mw of the acrylic random copolymer is a standard polystyrene-equivalent value measured by the GPC method using a GPC apparatus (HLC-8329GPC, manufactured by Tosoh Corporation), and the measurement conditions by the GPC method are the same as those described above.

[0144] The acrylic polymer preferably contains a crosslinking agent in order to further improve the cohesive strength of the pressure-sensitive adhesive layer.

[0145] The crosslinking agent is appropriately selected depending on the purpose, and examples thereof include isocyanate-based crosslinking agents, epoxy-based crosslinking agents, metal chelate-based crosslinking agents, and aziridine-based crosslinking agents. These may be used alone or in combination of two or more. Among these, the crosslinking agent is preferably a type that is mixed with the acrylic polymer after production to promote a crosslinking reaction, and it is more preferable to use an isocyanate-based crosslinking agent or an epoxy-based crosslinking agent that is highly reactive with the acrylic polymer.

[0146] Examples of the isocyanate-based crosslinking agent include tolylene diisocyanate, triphenylmethane isocyanate, naphthylene-1,5-diisocyanate, hexamethylene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, and trimethylolpropane-modified tolylene diisocyanate. These may be used alone or in combination of two or more. Among these, trifunctional polyisocyanate-based compounds such as tolylene diisocyanate and its trimethylolpropane adduct, and triphenylmethane isocyanate are particularly preferred.

[0147] When the above-mentioned crosslinking agent is used, the gel fraction of the adhesive layer can be set appropriately depending on the purpose. From the viewpoint of obtaining an adhesive layer with good cohesiveness and adhesiveness, the gel fraction is preferably 10% by mass or more and 70% by mass or less, more preferably 25% by mass or more and 65% by mass or less, and even more preferably 35% by mass or more and 60% by mass or less.

[0148] The gel fraction of the acrylic pressure-sensitive adhesive composition refers to a value measured by the following method. (Measurement method) The adhesive composition was coated onto a release sheet to a dry thickness of 50 μm, dried at 100°C for 3 minutes, and aged at 40°C for 2 days. A 50 mm square sample was then cut out. The mass of the sample before immersion in toluene was then measured. After immersion in toluene solution for 24 hours at 23°C, the toluene-insoluble portion of the sample was separated by filtration through a 300-mesh wire screen. The mass (G2) of the residue after drying at 110°C for 1 hour was measured. The gel fraction was calculated according to the following formula (2): Gel fraction (mass%) = G2 / G1 × 100 (2) In the formula (2), G1 is the mass of the sample before immersion in toluene, and G2 is the mass of the residue after drying at 110°C for 1 hour.

[0149] <<Rubber-based polymers>> When the pressure-sensitive adhesive layer is composed of a rubber-based pressure-sensitive adhesive composition, the pressure-sensitive adhesive layer contains one or more rubber polymers as a base polymer, and in the rubber-based pressure-sensitive adhesive composition, the proportion of the rubber polymer in 100 parts by mass of the base polymer is the same as the proportion of the acrylic polymer in 100 parts by mass of the base polymer described above.

[0150] Examples of the rubber-based polymer include non-diene rubber and diene rubber. Examples of the non-diene rubber include silicone rubber. Examples of the diene rubber include homopolymers of conjugated diene compounds and copolymers of conjugated diene compounds with other compounds. Examples of the homopolymer include polybutadiene, polyisoprene, polyisobutylene, and chloroprene rubber. Examples of the copolymer include acrylonitrile-butadiene rubber, styrene-butadiene rubber (SBR), and styrene-based resins.

[0151] Among them, the rubber-based polymer is preferably a styrene-based resin, more preferably the above-mentioned styrene-based block copolymer, even more preferably a block copolymer of an aromatic vinyl compound and a conjugated diene compound, and particularly preferably a block copolymer of a monovinyl-substituted aromatic compound and a conjugated diene compound. The above-mentioned monovinyl-substituted aromatic compound refers to a compound in which one functional group having a vinyl group is bonded to an aromatic ring. A typical example of the above-mentioned aromatic ring is a benzene ring. The benzene ring may not have a vinyl group, but may be substituted with a functional group such as an alkyl group.

[0152] The monovinyl-substituted aromatic compound constitutes the hard segment (A segment) in the block copolymer, and specific examples include styrene, α-methylstyrene, vinyltoluene, vinylxylene, etc. Among these, styrene is preferred. The conjugated diene compound constitutes the soft segment (B segment) in the block copolymer, and specific examples include 1,3-butadiene and isoprene.

[0153] The copolymerization ratio of the monovinyl-substituted aromatic compound in the styrene-based block copolymer is preferably 70% by mass or more, more preferably 90% by mass or more, and may be substantially 100% by mass, based on 100% by mass of the total mass of the block copolymer, although two or more types of monovinyl-substituted aromatic compounds may be used in combination.

[0154] The copolymerization ratio of the conjugated diene compound in the styrene-based block copolymer is preferably 70% by mass or more, more preferably 90% by mass or more, and may be substantially 100% by mass, based on 100% by mass of the total mass of the block copolymer. However, two or more types of conjugated dienes may be used in combination. Such a block copolymer can realize a pressure-sensitive adhesive tape with higher performance.

[0155] The styrene-based block copolymer may be in the form of a diblock copolymer, a triblock copolymer, a radial copolymer, a mixture thereof, or the like. Triblock copolymers and radial copolymers preferably have an A segment, such as a styrene block, at the end of the polymer chain. The A segments at the end of the polymer chain tend to aggregate to form domains, which is thought to form a pseudo-crosslinked structure and improve the cohesion of the PSA. The styrene-based block copolymer may also be a hydrogenated styrene-based block copolymer.

[0156] Specific examples of styrene-based block copolymers (including hydrogenated styrene-based block copolymers) of aromatic vinyl compounds and conjugated diene compounds include styrene-isoprene copolymer (SI), styrene-isoprene-styrene copolymer (SIS), styrene-isoprene-butadiene-styrene copolymer (SIBS), styrene-butadiene-styrene copolymer (SBS), styrene-ethylene-butylene-styrene copolymer (SEBS), and styrene-ethylene-propylene-styrene copolymer (SEPS).

[0157] The rubber polymer may be used alone or in combination of two or more. Among these, it is more preferable to use two or more styrene resins in combination, since this can provide the pressure-sensitive adhesive tape with excellent adhesive properties and holding power, and a mixture of a styrene-isoprene copolymer and a styrene-isoprene-styrene copolymer is particularly preferable.

[0158] <<Urethane polymer>> When the pressure-sensitive adhesive layer is composed of a urethane-based pressure-sensitive adhesive composition, the pressure-sensitive adhesive layer contains one or more urethane polymers as a base polymer, and in the urethane-based pressure-sensitive adhesive composition, the proportion of the urethane polymer in 100 parts by mass of the base polymer is the same as the proportion of the acrylic polymer in 100 parts by mass of the base polymer described above.

[0159] The urethane-based polymer may be a reaction product of a polyol and a polyisocyanate. The urethane-based polymer is not particularly limited as long as it can function as an adhesive, and examples thereof include ether-based polyurethane, ester-based polyurethane, and carbonate-based polyurethane. Examples of polyols constituting the urethane-based polymer include polyether polyol, polyester polyol, polycarbonate polyol, and polycaprolactone polyol. Examples of polyisocyanate compounds include diphenylmethane diisocyanate, tolylene diisocyanate, and hexamethylene diisocyanate.

[0160] (3) Optional components (tackifying resin) In addition to the base polymer and filler A, the pressure-sensitive adhesive layer may optionally contain a tackifier resin for the purpose of improving adhesion to an adherend or surface adhesive strength. The softening point of the tackifier resin is preferably 95°C or higher, from the viewpoint of improving the adhesive strength of the pressure-sensitive adhesive layer. The upper limit of the softening point is not particularly limited, but can be set to 200°C or lower. The softening point is more preferably 95°C to 180°C, and more preferably 95°C to 140°C.

[0161] The softening point of the tackifier resin is defined as a value measured by the softening point test method (ring and ball method) specified in either JIS K 5902 or JIS K 2207.

[0162] Specific examples of the tackifier resin include rosin-based tackifier resins, polymerized rosin-based tackifier resins, polymerized rosin ester-based tackifier resins, rosin phenol-based tackifier resins, stabilized rosin ester-based tackifier resins, disproportionated rosin ester-based tackifier resins, hydrogenated rosin ester-based tackifier resins, terpene-based tackifier resins, terpene phenol-based tackifier resins, petroleum resin-based tackifier resins, and (meth)acrylate-based tackifier resins. These may be used alone or in combination of two or more. Among these, tackifier resins selected from the group consisting of polymerized rosin ester-based tackifier resins, rosin phenol-based tackifier resins, disproportionated rosin ester-based tackifier resins, hydrogenated rosin ester-based tackifier resins, terpene phenol-based resins, and (meth)acrylate-based tackifier resins are preferred.

[0163] The content of the tackifier resin in the adhesive layer is not particularly limited and can be selected appropriately depending on the purpose, but is preferably 0% by mass or more and 65% by mass or less, and more preferably 8% by mass or more and 55% by mass or less, based on 100% by mass of the adhesive layer (solid content of the adhesive composition forming the adhesive layer).

[0164] (Other ingredients) The pressure-sensitive adhesive layer may contain other components as needed. The other components can be appropriately selected within a range that does not impair the properties of the pressure-sensitive adhesive tape. Examples include polymer components other than the base polymer, fillers other than Filler A (e.g., inorganic fillers, organic fillers with SP values ​​outside the range of Filler A, etc.), crosslinking agents, antioxidants, UV absorbers, fillers, polymerization inhibitors, surface conditioners, antistatic agents, antifoaming agents, viscosity modifiers, light stabilizers, weather stabilizers, heat stabilizers, antioxidants, leveling agents, organic pigments, inorganic pigments, pigment dispersants, plasticizers, softeners, flame retardants, metal deactivators, silica beads, organic beads, and other additives; and inorganic fillers such as silicon oxide, aluminum oxide, titanium oxide, zirconia, and antimony pentoxide. These may be used alone or in combination of two or more. The content of the other components in the pressure-sensitive adhesive layer of this embodiment can be appropriately set within a range that does not impair the properties of the pressure-sensitive adhesive tape.

[0165] (3) Adhesive layer The water contact angle of the base polymer contained in the pressure-sensitive adhesive layer is preferably 130° or less, more preferably 110° or less. The water contact angle of the base polymer is preferably 60° or more, more preferably 70° or more, and even more preferably 80° or more. Having a water contact angle of the base polymer within the above range ensures excellent compatibility with Filler A, enhances peelability in a low elongation range, and improves the effect of inhibiting re-application at elongated portions. Furthermore, the adhesive strength at the interface between the substrate and the pressure-sensitive adhesive layer can be increased.

[0166] The water contact angle of the base polymer is a value measured by the method for measuring the water contact angle of the base polymer described in the examples below.

[0167] The average thickness of the pressure-sensitive adhesive layer is not particularly limited as long as it can exhibit the desired adhesive strength, and can be, for example, from 1 μm to 200 μm, preferably from 3 μm to 80 μm, more preferably from 5 μm to 60 μm, and even more preferably from 10 μm to 30 μm. By setting the average thickness of the pressure-sensitive adhesive layer within the above range, the tape before stretching exhibits good adhesive strength, while the surface of the pressure-sensitive adhesive layer is more likely to be roughened by the filler during the stretching process, allowing the adhesive strength to decrease in a short period of time.

[0168] The average thickness of the pressure-sensitive adhesive layer is a value measured by the method for measuring the [average thickness] described in the Examples below. When the tape of the present disclosure is a double-sided tape, the average thickness of the pressure-sensitive adhesive layer refers to the average thickness of the pressure-sensitive adhesive layer on each side of the substrate. When the tape is a double-sided tape, the average thickness of the pressure-sensitive adhesive layer on one side and the average thickness of the pressure-sensitive adhesive layer on the other side may be the same or different.

[0169] The ratio of the average particle size of the filler to the average thickness of the pressure-sensitive adhesive layer (average particle size of filler / average thickness of pressure-sensitive adhesive layer) is preferably from 0.05 to 1, more preferably from 0.1 to 0.7, and even more preferably from 0.15 to 0.5. When the ratio of the thickness of the pressure-sensitive adhesive layer to the particle size of the filler is within the above range, the tape exhibits good adhesive strength before stretching, while the filler is likely to roughen the surface of the pressure-sensitive adhesive layer during stretching, allowing the surface adhesive strength of the tape in the low elongation range to be significantly reduced from the surface adhesive strength before stretching.

[0170] 3. Adhesive tape The adhesive tape of the present disclosure may have an adhesive layer on at least one side of the substrate directly or via another layer, and may have an adhesive layer on only one side of the substrate, or may have an adhesive layer on each of both sides.

[0171] The 100% modulus of the tape of the present disclosure is preferably 0.5 MPa or more and 30 MPa or less, more preferably 1.0 MPa or more and 20 MPa or less, even more preferably 1.5 MPa or more and 15 MPa or less, and particularly preferably 2.0 MPa or more and 10 MPa or less, because this allows the tape to be stretched with a small force in the initial stage of elongation and reduces the stress required from when the tape starts to elongate until it peels off from the adherend. The 300% modulus of the tape of the present disclosure is preferably 0.5 MPa or more and 50 MPa or less, more preferably 1.0 MPa or more and 40 MPa or less, even more preferably 1.5 MPa or more and 35 MPa or less, and particularly preferably 2.0 MPa or more and 30 MPa or less. The 100% modulus of the tape of the present disclosure is a value measured by the method for measuring 100% modulus described in the Examples below. The 300% modulus of the tape is measured in the same manner as the method for measuring 100% modulus described in the Examples, and is the stress value when the gauge length becomes four times the initial length (when the elongation of the modulus calculated by the following formula becomes 300%). Modulus elongation (%) = {(gauge length after elongation) - (gauge length before elongation)} / (gauge length before elongation)

[0172] The 100% modulus and 300% modulus of the tape of the present disclosure can be adjusted by adjusting the modulus of the substrate and the pressure-sensitive adhesive layer, and particularly by adjusting the modulus of the substrate.

[0173] The surface adhesive strength (initial splitting adhesive strength) P0 of the tape of the present disclosure before elongation is not particularly limited as long as it is strong enough to hold an adherend (especially a small component such as an MLCC) by temporary fixation, but is preferably 0.3 N / cm 2 More than 1N / cm is preferable. 2 More preferably, 2N / cm 2 The upper limit of the surface adhesive strength P0 of the tape of the present disclosure before elongation is not particularly limited as long as it can temporarily fix the adherend, but is not particularly limited to 25 N / cm 2 Less than 22N / cm is preferable. 2 Less than 20N / cm is more preferable. 2 The following is even more preferable: When the surface adhesive strength (initial splitting adhesive strength) P0 before stretching is within the above range, the tape surface can adequately hold the adherend, and high temporary fixation properties can be achieved.

[0174] In the tape of the present disclosure, the surface adhesive strength in the low elongation region is preferably significantly reduced from the initial surface adhesive strength, from the viewpoint of being able to release the temporarily fixed state of the adherend in the low elongation region and being able to suppress re-adhesion to the adherend. Specifically, the surface adhesive strength (splitting adhesive strength at 300% elongation) P of the tape of the present disclosure when elongated by 300% is 300 is 10N / cm 2 Preferably, it is less than 5N / cm 2 Less than 3N / cm is more preferable. 2 More preferably, 2N / cm 2 Less than 1.5N / cm is more preferable. 2 The following is particularly preferred: Surface adhesion P of the tape of the present disclosure 300 When the surface adhesive strength P is within the above range, it is possible to prevent the stretched tape from being re-attached to the adherend. 300 is 0N / cm 2 (i.e. adhesive strength has disappeared) and 0 N / cm 2 may be greater than 0.01 N / cm 2may be 0.1 N / cm or more, 2 It may be more than that.

[0175] The tape of the present disclosure has a surface adhesive strength P when stretched 300% relative to the surface adhesive strength P before stretching. 300 The ratio (P 300 / P0) is preferably 0.5 or less, more preferably 0.4 or less, even more preferably 0.3 or less, even more preferably 0.25 or less, and particularly preferably 0.18 or less. 300 By setting the ratio (P / P0) in the above range, it is possible to achieve both temporary fixation of the adherend and suppression of re-adhesion when peeled from the adherend. 300 The lower limit of / P0) is not particularly limited, but may be, for example, 0.01 or more, 0.05 or more, or 0.1 or more.

[0176] The surface adhesive strength P0 and P 300 can be adjusted by selecting, for example, the type and physical properties of the base polymer in the pressure-sensitive adhesive layer, the type and physical properties of the filler, etc.

[0177] The surface adhesive strength P0 and P 300 are the surface adhesive strength before elongation (P0) and the surface adhesive strength after 300% elongation (P 300 The surface adhesive strength of the tape is the splitting adhesive strength.

[0178] The 180° peel adhesive strength of the tape of the present disclosure is preferably 0.1 N / 20 mm or more, preferably 0.5 N / 20 mm or more, more preferably 1.5 N / 20 mm or more, and even more preferably 2.0 N / 20 mm or more. With a 180° peel strength within the above range, the tape of the present disclosure can sufficiently temporarily fix an adherend, allowing processing, etc., to be performed in the temporarily fixed state. At the same time, when stretched and peeled from the adherend, the increase in peel strength is suppressed, allowing peeling in a low elongation range, and providing good removability. The upper limit of the initial 180° peel adhesive strength of the tape of the present disclosure is not particularly limited and can be set appropriately depending on the application of the tape of the present disclosure (temporary fixing application, joining application, etc.). The upper limit of the initial 180° peel adhesive strength can be, for example, 20 N / 20 mm or less, preferably 15 N / 20 mm or less, more preferably 13 N / 20 mm or less, even more preferably 11 N / 20 mm or less, and particularly preferably 10 N / 20 mm or less.

[0179] The 180° peel adhesive strength of the tape of the present disclosure is a value measured by the method for measuring 180° peel adhesive strength described in the examples below.

[0180] The breaking strength of the tape of the present disclosure is not particularly limited as long as it is difficult to break during stretching and can be peeled from the adherend, but is, for example, preferably 5 MPa to 130 MPa, more preferably 10 MPa to 120 MPa, even more preferably 15 MPa to 110 MPa, and particularly preferably 20 MPa to 100 MPa. When the breaking strength of the tape of the present disclosure is within the above range, the tape is prevented from tearing during stretching and the stress when stretching the tape can be reduced.

[0181] The breaking elongation of the tape of the present disclosure is not particularly limited as long as it is difficult to break during stretching and can be peeled from the adherend, but is, for example, preferably 200% to 1000%, more preferably 250% to 800%, even more preferably 300% to 600%, and particularly preferably 350% to 600%. By setting the breaking elongation of the tape of the present disclosure within the above range, excessive stress when stretching the tape of the present disclosure can be suppressed, and the stretching distance required for the adherend to peel from the tape of the present disclosure can be shortened.

[0182] The breaking elongation and breaking strength of the tape of the present disclosure can be adjusted, for example, by the breaking elongation and breaking strength of each layer constituting the tape, particularly the breaking elongation and breaking strength of the substrate.

[0183] The breaking elongation and breaking strength of the tape of the present disclosure are values ​​measured by the measuring method for [breaking strength and breaking elongation] described in the examples below.

[0184] The tape of the present disclosure may have a release liner on the surface of the adhesive layer. Known release liners can be used, such as paper, plastic film, polytetrafluoroethylene (PTFE) film, or plastic film whose surface has been subjected to a release treatment such as silicone treatment or silicone fluoride treatment. The release liner is usually peeled off and removed when an adherend is adhered to the tape of the present disclosure. When the tape of the present disclosure is a double-sided adhesive tape having adhesive surfaces on both sides, a release liner may be provided on one adhesive surface of the tape of the present disclosure, or on both adhesive surfaces.

[0185] The tape of the present disclosure can be produced by a known tape production method, for example, a method in which a pressure-sensitive adhesive composition containing a base polymer and a filler exhibiting a predetermined SP value is directly applied to a substrate and dried to form a pressure-sensitive adhesive layer, or a method in which the pressure-sensitive adhesive composition is applied to a release liner and dried to form a pressure-sensitive adhesive layer, which is then transferred to a substrate.

[0186] II. Parts manufacturing method The method for manufacturing a component according to the present disclosure is a method for manufacturing a component using the adhesive tape described above in the section "I. Adhesive Tape," and includes a peeling step of stretching the adhesive tape, to which one or more components are fixed, in at least one direction to peel the components from the adhesive tape.

[0187] Fig. 1 is a process diagram showing an example of a method for manufacturing a component according to the present disclosure. The method for manufacturing a component according to the present disclosure includes a peeling step of stretching a temporary fixing tape 1 having one or more components 5 fixed thereto in at least one direction D, and peeling the components 5 from the temporary fixing tape 1. The temporary fixing tape 1 illustrated in Fig. 1 is a single-sided tape having a pressure-sensitive adhesive layer 3 on one side of a substrate 2. The same is true for the temporary fixing tape 1 illustrated in Fig. 2, which will be described later.

[0188] According to the component manufacturing method of the present disclosure, from a state in which a component is fixed to the adhesive tape described in the above section "I. Adhesive Tape," the component can be easily and simply peeled from the adhesive tape by simply stretching the adhesive tape in at least one direction, without the need for heating, irradiation with active energy rays, or the like. Furthermore, because the adhesive tape used in the component manufacturing method of the present disclosure has a predetermined adhesive layer, not only does the surface adhesive strength decrease when the tape is stretched, but the surface adhesive strength is also unlikely to recover over time. Therefore, according to the component manufacturing method of the present disclosure, adhesive residue is unlikely to remain on the peeled component, and re-attaching of a peeled component to the tape can be suppressed.

[0189] (1) Peeling process The method for manufacturing a component according to the present disclosure includes a peeling step of stretching the adhesive tape having one or more components fixed thereto in at least one direction to peel the components from the adhesive tape.

[0190] The stretching direction of the adhesive tape can be set arbitrarily when viewed from above. The stretching direction may be at least one direction, or may be one direction, two intersecting directions, three or more multiaxial directions, or all directions (360°). When the adhesive tape has a long shape, the stretching direction may be the longitudinal direction of the adhesive tape, a direction generally perpendicular to the longitudinal direction (short direction), a direction inclined at a desired angle to the longitudinal direction, a combination of these directions, or all directions radially from an arbitrary point (reference point) as the center. Note that when one stretching direction and the other stretching direction of the tape are 180° opposite to each other, the two stretching directions are considered to be bidirectional and the same direction. The stretching direction D shown in Figure 1(a) shows an example of bidirectional stretching from both sides of the tape. The stretching direction may also be unidirectional (for example, only one of the two arrow directions D in Figure 1(a)).

[0191] When the adhesive tape is stretched in two or more directions, it may be stretched simultaneously in two or more directions (simultaneous stretching), or may be stretched sequentially in each direction (sequential stretching).

[0192] When the adhesive tape is stretched in two directions, the first direction and the second direction are preferably generally perpendicular to each other. "Generally perpendicular" does not mean that the second direction does not have to be exactly 90° relative to the first direction, as long as it is approximately 90°, but an angle of, for example, 85° to 95°, or even 88° to 92° is acceptable.

[0193] The means (stretching member) for stretching the adhesive tape is not particularly limited, and examples thereof include a roll, an expander, a tension and expansion jig, a stage, and a pin. These are preferably movable. For example, the stage and pin are preferably movable up and down. After stretching the adhesive tape, the stretched state may be maintained by a grip ring or the like.

[0194] The method for stretching the adhesive tape is not particularly limited, but examples include a method in which the peripheral edge of the adhesive tape is clamped with a stretching member (e.g., a tensile extension jig) and pulled in a certain direction, a method in which the adhesive tape is pulled using the peripheral speed of two stretching members (e.g., rolls), and a method in which the rotation directions of two opposing stretching members (e.g., rolls) are opposite (e.g., one roll rotates clockwise and the other opposing roll rotates counterclockwise) and the tape is pulled.

[0195] As another method for stretching the adhesive tape, for example, a stretching member may be pressed against the adhesive tape from the side opposite to the side on which the component is placed, and the adhesive tape may be pushed out (protruded) toward the side on which the component is placed, and then the adhesive tape may be stretched. By pulling the adhesive tape in this way, the adhesive tape can be stretched in all directions, and multiple components can be peeled off from the adhesive tape at one time.

[0196] Examples of stretching members used when pressing against one side of the adhesive tape to pull the adhesive tape include a stage, a pin, etc. The stretching member is pressed against the adhesive tape from the side opposite to the side on which the components are placed, and the side on which the components are placed may be the upper or lower surface when viewed from the side of the adhesive tape. When components are placed (fixed) on the lower surface of the adhesive tape, pressing the stretching member against the upper surface of the adhesive tape causes the components to peel off from the adhesive tape and simultaneously fall under their own weight, allowing them to be separated from the adhesive tape.

[0197] The peeling process may be performed on a component manufacturing line or offline. When the peeling process is performed on a component manufacturing line, the tape is preferably stretched in a direction intersecting the tape feed direction, and more preferably in a direction generally perpendicular to the feed direction, since this allows the component to be peeled while the tape is being fed. Examples of methods for stretching the tape in a direction generally perpendicular to the feed direction include a method of gripping and expanding the end of the tape in the width direction. Furthermore, when the peeling process is performed on a component manufacturing line, the tape may be stretched in all directions. Examples of methods for stretching the tape in all directions include a method of pressing a stretching member against the tape being fed from the side opposite the component placement side, thereby protruding the tape so that it forms a convex shape toward the component placement side (a method of pushing up or down).

[0198] When the method for manufacturing a part according to the present disclosure further includes a processing step, which is an optional step described below, in the peeling step, the part processed in the processing step (also referred to as the processed product or the processed member) is peeled off from the adhesive tape.

[0199] (2) Optional process The component manufacturing method of the present disclosure includes at least the peeling step described above, but may also include one or more other steps. The other steps that can be optionally included are described below.

[0200] (a) Processing process The method for manufacturing a part according to the present disclosure may further include a processing step of processing the part fixed on the adhesive layer of the adhesive tape. The processing step is usually carried out before the peeling step, in which the part before processing (workpiece) is fixed to the adhesive tape in the processing step, and the part after processing (workpiece) is peeled off from the adhesive tape in the peeling step.

[0201] The type of processing applied to the part is not particularly limited, and examples include cutting, polishing, cutting, etching, and the like.

[0202] (b) Transfer process The method for manufacturing a component according to the present disclosure may include a transfer step of fixing a transfer target to a surface of the component opposite to the surface that contacts the adhesive tape, and stretching the adhesive tape to transfer the component to the transfer target. The transfer step is performed simultaneously with the peeling step, and therefore can be included in the peeling step.

[0203] 2 is a process diagram showing another example of a component manufacturing method according to the present disclosure, illustrating an example in which a peeling step and a transfer step are performed simultaneously. In the component manufacturing method illustrated in FIG. 2, a transferee 200 is placed on the surface of the component 5 opposite the surface to which the temporary fixing tape 1 is attached (FIG. 2(a)). From a composite having the temporary fixing tape 1, the component 5, and the transferee 200 in this order, the temporary fixing tape 1 is pulled in direction D to stretch the temporary fixing tape 1, thereby peeling the component 5 from the temporary fixing tape 1 (peeling step) and simultaneously transferring the component 5 to the transferee 200 (transfer step) (FIGS. 2(b) and 2(c)). The stretching direction D shown in FIG. 2(b) illustrates an example in which the temporary fixing tape 1 is stretched bidirectionally from both sides.

[0204] The object onto which the component is transferred is not particularly limited as long as it can directly or indirectly fix the transferred component, and examples thereof include adhesive tape, sticky tape, and other components coated with adhesive.

[0205] (c) Separation process The component manufacturing method of the present disclosure may include a separation step of separating the component from the adhesive tape after the peeling step. The separation method may involve various means, such as suction, clamping, sweeping, etc., to separate the peeled component from the adhesive tape, or the peeled component may be separated from the adhesive tape by allowing it to fall under its own weight. The component may also be separated from the tape by applying vibration to the tape. Examples of the suction means include a suction cup, a suction machine, a suction collet, etc. Examples of the clamping means include tweezers, a clamp, etc. Examples of the sweeping means include a swinging plate, wind pressure, a brush, etc. Separation of the component from the adhesive tape by allowing it to fall under its own weight may occur simultaneously with the peeling step.

[0206] (d) Optional process The method for manufacturing a component according to the present disclosure may also include one or more optional steps, such as a post-peeling processing step for processing the component peeled from the tape, an assembly step for assembling two or more components, a cleaning step for cleaning the component, a curing step for curing the component, etc. The timing for performing the optional steps can be selected as appropriate.

[0207] (3) Parts The size of each component peeled off from the adhesive tape in the peeling step is not particularly limited, but is preferably millimeter-level, more preferably micro-level, and more preferably within the dimensions specified in JIS C 5101-22:2014 (IEC 60384-22:2011).

[0208] The surface area of ​​the surface of each component that is peeled off in the peeling step that comes into contact with the adhesive tape is not particularly limited, but is preferably 50 mm 2 Preferably, it is less than 30 mm 2 Preferably, it is less than 10 mm 2 Preferably less than 3 mm 2 Preferably, it is less than 1 mm 2 Preferably, it is less than 0.5 mm 2 The following is preferable, with 0.2 mm being the most preferable. 2 The lower limit of the surface area is not particularly limited, but for example, it is 0.001 mm 2 More than 0.01 mm, preferably 0.01 mm 2 It can be more than that.

[0209] Components that can be manufactured by the component manufacturing method of the present disclosure are not particularly limited, but components having the above-mentioned sizes are preferred, and examples thereof include semiconductor wafers, semiconductor elements, capacitors such as multilayer ceramic capacitors, various chips such as chip resistors, and microelectronic components such as inductors.

[0210] The present disclosure is not limited to the above-described embodiments. The above-described embodiments are merely examples, and any configuration that is substantially identical to the technical idea described in the claims of the present disclosure and that provides similar effects is included within the technical scope of the present disclosure. [Example]

[0211] The present disclosure will be described in detail below with reference to examples, but the present disclosure is not limited thereto.

[0212] 1. Measurement and Evaluation Each physical property was measured by the following methods.

[0213] [Filler content (vol %) in adhesive layer (solid content of adhesive composition)] The specific gravity of each component of the adhesive resin composition (base polymer, tackifying resin, filler, optional components, etc.) was measured in accordance with the method of JIS K 7112. The content (volume %) of the filler in each adhesive composition (solid content) was calculated using the following calculation formulas 1 to 3. Formula 1: (Filler content / Filler specific gravity) = Filler volume Equation 2: (amount of base polymer blended / specific gravity of base polymer)+(amount of tackifier resin blended / specific gravity of tackifier resin)+(amount of filler blended / specific gravity of filler)+(amount of optional component blended / specific gravity of optional component)=volume of PSA composition (solid content) Equation 3: (Volume of filler) / (Volume of adhesive composition (solid content))×100=Filler content [volume %]

[0214] [Breaking strength and breaking elongation] The test specimens were punched into a No. 3 dumbbell shape with a gauge length of 20 mm and a width of 5 mm, and pulled lengthwise at a speed of 500 mm / min using a Tensilon tensile testing machine (model: RTF-1210, manufactured by A&D Co., Ltd.) under conditions of 23°C and 50% RH. The tensile elongation measured at break was taken as the breaking elongation of the test specimen, and the stress value was taken as the breaking strength of the test specimen.

[0215] [100% modulus] The test specimen was cut into a JIS K6251 No. 3 dumbbell shape (gauge length 20 mm, width 5 mm) and pulled longitudinally at a tensile speed of 500 mm / min using a Tensilon tensile testing machine (model: RTF-1210, manufactured by A&D Co., Ltd.) under conditions of 23°C and 50% RH. The stress value when the gauge length became twice the initial length (when the elongation calculated by the formula below was 100%) was taken as the 100% modulus of the test specimen. Modulus elongation (%) = {(gauge length after elongation) - (gauge length before elongation)} / (gauge length before elongation)

[0216] Average Thickness The thickness of each of the five points at 10 mm intervals across the width of the object was measured using a TH-104 paper / film thickness measuring instrument (manufactured by Tester Sangyo Co., Ltd.), and the average value of the five points was taken as the average thickness.

[0217] [Rubber hardness] Using a durometer (spring type rubber hardness tester, model: GS-719G, manufactured by Teclock Corporation), rubber hardness (Type A, also called Shore A) was measured in accordance with JIS K 6253.

[0218] [Water contact angle of base polymer] The base polymer was formed into a sheet, and 3 μL of purified water was dropped onto the surface, and the contact angle after 1 second was measured using an automatic contact angle meter (DROMPAMSTER500, manufactured by Kyowa Interface Science Co., Ltd.) The contact angle was calculated according to the sessile drop method described in JIS R3257.

[0219] [Average particle size of filler] The average particle size (primary particle size) of the filler was measured using a measuring instrument (Microtrac) that uses the laser diffraction scattering method. The particle size of the filler was measured using a measuring instrument that uses the laser diffraction scattering method such as Microtrac, and a cumulative curve of the volume versus particle size was obtained, with the total volume of the filler being 100%, and the particle size at the point on the cumulative curve where the cumulative volume was 50% was taken as the average particle size.

[0220] [Solubility parameter of filler (SP value)] The values ​​used were those listed in Plastic Solubility | Technical Information | (MISUMI-VONA (misumi-ec.com)), Solubility Parameter (SP Value) of Homopolymers and Resins - Plastic Material Dictionary (https: / / jp.misumi-ec.com / tech-info / categories / plastic_mold_design / pl09 / c0897.html), Plastic Technology Reader published by Kogyo Chosakai Co., Ltd. (authored by Sakurauchi Yujiro, published December 1, 1993), and Optimal Design and Application Technology of Pressure Sensitive Adhesives and Adhesives published by Technical Information Association Co., Ltd. (1st edition, published June 30, 2014).

[0221] [180° peel adhesive strength] According to JIS Z 0237, a test piece was prepared by attaching a 25 μm thick PET film as a backing to one surface of the adhesive layer of a pressure-sensitive adhesive tape cut into a length of 150 mm and a width of 20 mm. The other surface of the adhesive layer of the test piece (the surface to be measured) was then attached to a stainless steel plate (length 100 mm, width 30 mm, thickness 3 mm) under an ambient temperature of 23°C and 50% RH. The test piece was then pressed back and forth with a roller under a load of 2 kg, and allowed to stand for 1 hour under an ambient temperature of 23°C and 50% RH. The test piece was then peeled from the stainless steel plate in a 180° direction at a pulling rate of 300 mm / min under an ambient temperature of 23°C and 50% RH using the Tensilon tensile tester (model: RTF-1210, manufactured by A&D Co., Ltd.) to measure the 180° peel adhesive strength (N / 20 mm) of the pressure-sensitive adhesive tape.

[0222] [Surface adhesion strength before elongation (P0)] A test stage was created by attaching strong adhesive double-sided tape (#8840ER, manufactured by DIC Corporation) to the surface of a 2 mm thick stainless steel plate. The tape to be used as a test piece was cut to 30 mm x 50 mm and attached to the strong adhesive double-sided tape of the test stage, exposing the surface of the adhesive layer to be measured. The bottom of a stainless steel block (10 mm x 10 mm x 40 mm in size, with the 10 mm x 10 mm surface being the bottom) was pressed against the exposed surface of the adhesive layer of the test piece with a load of 50 N / cm. 2 The stainless steel square bar was peeled off from the test piece in the split direction at a rate of 1000 mm / min in an atmosphere of 23°C and 50% RH, and the strength was measured, which was designated as the surface adhesive strength P0 before elongation.

[0223] [Surface adhesive strength at 300% elongation (P 300 )] A test stage was prepared by attaching strong adhesive double-sided tape (#8840ER, manufactured by DIC Corporation) to the surface of a 2 mm thick stainless steel plate to secure the adhesive tape that would serve as the test specimen. The adhesive tape was cut to 30 mm x 50 mm, and a gauge line was written 10 mm from each end in the longitudinal direction to prepare the test specimen (the initial gauge line distance of the test specimen was 30 mm). The test specimen was stretched in the longitudinal direction until the gauge line distance reached 120 mm (the elongation calculated using the formula below was 300%), and then attached to the strong adhesive double-sided tape of the test stage with the adhesive layer of the test specimen facing away from the stainless steel plate. The bottom surface of a stainless steel block (10 mm x 10 mm x 40 mm in size, with the 10 mm x 10 mm surface (10 mm square surface) as the bottom surface) was pressed against the exposed adhesive layer of the test specimen with a load of 50 N / cm. 2 The stainless steel square bar was peeled off from the test piece in the split direction at a speed of 1000 mm / min in an atmosphere of 23°C and 50% RH for 10 seconds. The strength was measured, and the surface adhesive strength P at 300% elongation was 300 It was decided. Elongation (%) = {(gauge length after elongation) - (gauge length before elongation)} / (gauge length before elongation) x 100

[0224] [P 300 / P0] The above [surface adhesive strength before elongation (P0)] and [surface adhesive strength at 300% elongation (P 300 )], the surface adhesive force P when stretched 300% relative to the surface adhesive force P before stretching 300 Ratio of (P 300 / P0) was calculated.

[0225] [Removability 1 (initial removability)] A 10mm wide x 60mm long adhesive tape was attached to a clean, smooth aluminum plate with a 10mm wide x 10mm long grip at one end of the tape, with the grip extending beyond the aluminum plate. A clean, smooth acrylic plate was then attached to the opposite side of the tape, and pressure was applied with a roller once back and forth under a 2kg load. The tape was then left for 60 minutes at 23°C and 50% RH to obtain a test specimen. The adhesive tape was stretched horizontally by 10mm using the grip at 23°C and 50% RH. The tape was then folded back toward the acrylic plate and stretched 180° at a rate of approximately 300mm / min, and the adhesive tape was then peeled off from the test specimen. This series of procedures was performed on 10 test specimens. After each peel, the degree of tape tearing and the degree of adhesive residue on the adherend (both the aluminum plate and the acrylic plate) were visually evaluated and rated according to the following criteria. (Criteria) ◎: The adhesive tape was peeled off without breaking all 10 times and was peeled off cleanly without leaving any adhesive residue on the adherend. ○: The adhesive tape was peeled off all 10 times without breaking, but adhesive residue was left on only one occasion. △: The adhesive tape broke and could not be peeled off 1 to 4 times out of 10 times. ×: The adhesive tape broke and could not be peeled off 5 or more times out of 10 times.

[0226] [Removability 2 (with mid-way stop)] A test specimen was prepared in the same manner as in "Removability 1 (Initial Removability)" above. The adhesive tape was gripped by the gripper and stretched horizontally by 10 mm. The tape was then folded back toward the acrylic plate and stretched in a 180° direction at a speed of approximately 300 mm / min. The tape was then peeled 30 mm from the edge of the aluminum plate, stopping the stretch. A 2 kg load was again applied from the acrylic plate side, and pressure was applied back and forth with a roller. The gripper portion was then stretched again in a 180° direction by hand at a speed of approximately 300 mm / min. This series of operations was repeated 10 times. After each peel, the degree of tape breakage and the degree of adhesive residue on the adherend (both the aluminum plate and the acrylic plate) were visually evaluated and rated according to the following criteria: (Criteria) ⊚: The adhesive tape was peeled cleanly without breakage and without leaving any adhesive residue on the adherend in all 10 attempts. ○: The adhesive tape was peeled cleanly without breakage in all 10 attempts, but adhesive residue remained on only one of the attempts. △: The adhesive tape broke and could not be peeled off 1 to 4 times out of 10. ×: The adhesive tape broke and could not be peeled off 5 or more times out of 10.

[0227] 2.Material The materials used in manufacturing the adhesive tape are listed below.

[0228] [Base material] Substrate (1): Substrate (50 μm thick) made of styrene-ethylene-ethylene / propylene-styrene block copolymer (SEEPS) manufactured by the following manufacturing method. Substrate (2): Film of ester-based polyurethane compound (Mobilon Film MF50T, manufactured by Nisshinbo Textile Inc., thickness 50 μm). Substrate (3): Film of polyethylene terephthalate (PET) (Lumira-S10, manufactured by Toray Industries, Inc., thickness 50 μm).

[0229] (Method for manufacturing substrate (1)) A pressure vessel was purged with nitrogen and dried. 3,000 mL of cyclohexane as solvent and 9.2 mL of a 10.5% by weight solution of sec-butyllithium in cyclohexane were charged and heated to 60°C. 100 mL of styrene was added and polymerized for 60 minutes. 270 mL of isoprene and 350 mL of butadiene were then added at the same temperature, and the reaction continued for 90 minutes. 100 mL of styrene was then added at the same temperature and polymerized for 60 minutes. 0.52 mL of methanol was added to terminate the polymerization, yielding a polymerization reaction solution containing a block copolymer. 29.3 g of palladium carbon (palladium loading: 5% by weight) was added as a hydrogenation catalyst to the polymerization reaction solution, and the hydrogenation reaction was carried out at 150°C for 10 hours under a hydrogen pressure of 2 MPa. After cooling and depressurization, the palladium carbon was removed by filtration. The filtrate was concentrated and further dried in vacuo to obtain the substrate material (1). The obtained substrate material (1) was a styrene-ethylene-ethylene / propylene-styrene block copolymer (SEEPS) with a styrene content of 30% by mass, a weight average molecular weight of 98,000, a molecular weight distribution of 1.03, and a hydrogenation rate of 98%. Next, toluene was added to the substrate material (1) and stirred to make it uniform, and the mixture was applied to a release liner with an applicator so that the thickness after drying would be 50 μm, and then dried at 60° C. for 15 minutes to produce the substrate (1).

[0230] [Filler] Filler (1): Nylon filler (Toray Industries, Inc. "SP-10", volume average particle size 9 μm, specific gravity 1.02) Filler (2): Cellulose acetate filler (Daicel Corporation "BELLOCEA S7", volume average particle size 7 μm, specific gravity 1.35) Filler (3): Silicone filler (Shin-Etsu Chemical Co., Ltd. "KMP-601", volume average particle size 12 μm, specific gravity 1.02)

[0231] [Base polymer] Base polymer (1): An acrylic triblock copolymer of polymethyl methacrylate (PMMA) block-polyn-butyl acrylate (PnBA) block-polymethyl methacrylate (PMMA) block (PMMA-b-PnBA-b-PMMA, specific gravity: 1.1, referred to as acrylic triblock copolymer A), synthesized in Synthesis Example 1 below. Base polymer (2): An acrylic triblock copolymer of polymethyl methacrylate (PMMA) block-polyn-butyl acrylate (PnBA) / poly2-ethylhexyl acrylate (2EHA) block-polymethyl methacrylate (PMMA) block (PMMA-b-PnBA / 2EHA-b-PMMA, specific gravity: 1.1, referred to as acrylic triblock copolymer B), synthesized in Synthesis Example 2 below. Base polymer (3): A mixture of styrene-isoprene diblock copolymer and styrene-isoprene-styrene triblock copolymer (referred to as styrene-based copolymer A). In the styrene copolymer A, the structural unit derived from styrene was 24% by mass, the proportion of the styrene-isoprene diblock copolymer to the total amount of the styrene copolymer A was 67% by mass, and the specific gravity of the styrene copolymer A was 0.91.

[0232] (Synthesis Example 1: Acrylic Triblock Copolymer A) A mixed solution was prepared by adding 500 ml of dry toluene and 80 ml of a dry toluene solution containing 0.75 g of bis(pentamethylcyclopentadienyl)samarium tetrahydrofuranate complex [(C5Me5)2SmMe(THF)] as a polymerization initiator to a 1000 ml flask purged with argon. 12.0 ml of methyl methacrylate (MMA) was added to the mixed solution at 0 °C and stirred at 0 °C for 30 minutes. A 20 ml sample was then taken from the system (Sample 1). After polymerization of the MMA, the polymerization reaction system was cooled to -78 °C, and 88.0 ml of n-butyl acrylate (nBA) was added as the second monomer. The mixture was stirred at -78 °C for 3 hours. A 20 ml sample was then taken from the system (Sample 2). After the polymerization of nBA, 12.0 ml of MMA was added to the polymerization system as the third monomer at -78°C, and the solution was stirred. After the solution became homogeneous, it was heated to 0°C and stirred for an additional hour. The polymerization was terminated by adding 50 ml of methanol to the resulting reaction mixture and reacting at room temperature for 2 hours. The reaction solution after polymerization termination was poured into a large amount of hexane, and a white precipitate was obtained. A portion of the resulting white precipitate was sampled (Sample 3).

[0233] NMR, DSC, and GPC (gel permeation chromatography) measurements were performed on each of the polymers in Samples 1 to 3. Based on the measurement results, the number average molecular weight (Mn), PMMA / PnBA (polymethyl methacrylate block / polyn-butyl acrylate block) ratio, etc. were determined, and it was confirmed that the white precipitate was an acrylic triblock copolymer (PMMA-b-PnBA-b-PMMA) of polymethyl methacrylate (PMMA) block-polyn-butyl acrylate (PnBA) block-polymethyl methacrylate (PMMA) block. The PMMA block of the acrylic triblock copolymer (PMMA-b-PnBA-b-PMMA) had a syndiotacticity of 71%, a glass transition temperature of 113.7°C, and a glass transition temperature of -46.8°C for the PnBA block. The Mn of the entire copolymer was 95,936, the Mw / Mn (molecular weight distribution) of the entire copolymer was 1.09, and the proportions of the polymer blocks were confirmed to be PMMA (11% by weight), PnBA (78% by weight), and PMMA (11% by weight).

[0234] (Synthesis Example 2: Acrylic Triblock Copolymer B) A mixed solution was prepared in a 1000 ml flask with an argon atmosphere by adding 500 ml of dry toluene and 80 ml of a dry toluene solution containing 0.75 g of bis(pentamethylcyclopentadienyl)samarium tetrahydrofuranate complex [(C5Me5)2SmMe(THF)] as a polymerization initiator. 6.0 ml of MMA was added to the mixed solution at 0 °C and stirred at 0 °C for 30 minutes. A 20 ml sample was then taken from the system (Sample 4). After the MMA polymerization, the polymerization reaction system was cooled to -78 °C, and 27.2 ml of nBA and 22.1 ml of 2-ethylhexyl acrylate (hereinafter referred to as "2EHA") were added as the second monomer. The mixture was stirred at -78 °C for 3 hours. A 20 ml sample was then taken from the system (Sample 5). After the polymerization of nBA, 6.0 ml of MMA was added to the polymerization system as the third monomer at -78°C, and the solution was stirred. After the solution became homogeneous, it was heated to 0°C and stirred for an additional hour. The polymerization was terminated by adding 50 ml of methanol to the resulting reaction mixture and reacting at room temperature for 2 hours. The reaction solution after polymerization termination was poured into a large amount of hexane, and a white precipitate was obtained. A portion of the white precipitate was then sampled (Sample 6).

[0235] NMR, DSC, and GPC (gel permeation chromatography) measurements were performed on each of the polymers in Samples 4 to 6. Based on the obtained measurement results, the number average molecular weight (Mn), PMMA / PnBA / P2EHA (polymethyl methacrylate / polyn-butyl acrylate / poly2-ethylhexyl acrylate) ratio, etc. were determined, and it was confirmed that the white precipitate was an acrylic triblock copolymer (PMMA-b-PnBA / 2EHA-b-PMMA) of polymethyl methacrylate (PMMA) block-polyn-butyl acrylate (PnBA) / poly2-ethylhexyl acrylate (2EHA) block-polymethyl methacrylate (PMMA) block. The PMMA block of the acrylic triblock copolymer (PMMA-b-PnBA / 2EHA-b-PMMA) had a syndiotacticity of 75%, a glass transition temperature of 105.8°C, and a glass transition temperature of -53.6°C for the PnBA block. The Mn of the entire copolymer was 51,370, and the Mw / Mn (molecular weight distribution) of the entire copolymer was 1.15. The proportions of the individual polymer blocks were confirmed to be PMMA (10 wt%)-PnBA (44 wt%) / 2EHA (36 wt%)-PMMA (10 wt%).

[0236] [Adhesive composition] (Preparation Example 1: Pressure-sensitive adhesive composition 1) 100 parts by mass of the base polymer (1), 50 parts by mass of a terpene phenol resin (Arakawa Chemical Industries, Ltd. "Tamanol T-803L", softening point 150°C, specific gravity 1.07) as a tackifier resin, 47 parts by mass of the filler (1), and ethyl acetate (solvent) were stirred and mixed uniformly to obtain a pressure-sensitive adhesive composition 1 having a solid content of 40% by mass.

[0237] (Preparation Example 2: Pressure-sensitive adhesive composition 2) 100 parts by mass of the base polymer (1), 50 parts by mass of a terpene phenol resin (Arakawa Chemical Industries, Ltd. "Tamanol T-803L", softening point 150°C, specific gravity 1.07) as a tackifier resin, 62 parts by mass of the filler (2), and ethyl acetate (solvent) were stirred and mixed uniformly to obtain a pressure-sensitive adhesive composition 2 having a solid content of 40% by mass.

[0238] (Preparation Example 3: Pressure-sensitive adhesive composition 3) 100 parts by mass of the base polymer (1), 50 parts by mass of a terpene phenol resin (Arakawa Chemical Industries, Ltd. "Tamanol T-803L", softening point 150°C, specific gravity 1.07) as a tackifying resin, 75 parts by mass of the filler (1), and ethyl acetate (solvent) were stirred and mixed uniformly to obtain a pressure-sensitive adhesive composition 3 having a solid content of 40% by mass.

[0239] (Preparation Example 4: Pressure-sensitive adhesive composition 4) 100 parts by mass of the base polymer (1), 50 parts by mass of a terpene phenol resin (Arakawa Chemical Industries, Ltd. "Tamanol T-803L", softening point 150°C, specific gravity 1.07) as a tackifier resin, 25 parts by mass of the filler (1), and ethyl acetate (solvent) were stirred and mixed to homogeneity to obtain a pressure-sensitive adhesive composition 4 having a solid content of 40% by mass.

[0240] (Preparation Example 5: Pressure-sensitive adhesive composition 5) 100 parts by mass of the base polymer (1), 50 parts by mass of a terpene phenol resin (Arakawa Chemical Industries, Ltd. "Tamanol T-803L", softening point 150°C, specific gravity 1.07) as a tackifier resin, and ethyl acetate (solvent) were stirred and mixed to homogeneity to obtain a pressure-sensitive adhesive composition 5 having a solid content of 40% by mass.

[0241] (Preparation Example 6: Pressure-sensitive adhesive composition 6) 100 parts by mass of the base polymer (1), 50 parts by mass of a terpene phenol resin (Arakawa Chemical Industries, Ltd. "Tamanol T-803L", softening point 150°C, specific gravity 1.07) as a tackifier resin, 45 parts by mass of the filler (3), and ethyl acetate (solvent) were uniformly stirred and mixed to obtain a pressure-sensitive adhesive composition 6 having a solid content of 40% by mass.

[0242] (Preparation Example 7: Pressure-sensitive adhesive composition 7) 100 parts by mass of the base polymer (2), 50 parts by mass of a terpene phenol resin (Arakawa Chemical Industries, Ltd. "Tamanol T-803L", softening point 150°C, specific gravity 1.07) as a tackifier resin, 47 parts by mass of the filler (1), and ethyl acetate (solvent) were uniformly stirred and mixed to obtain a pressure-sensitive adhesive composition 7 having a solid content of 40% by mass.

[0243] (Preparation Example 8: Pressure-sensitive adhesive composition 8) 100 parts by mass of the base polymer (3), 40 parts by mass of a C5 / C9 aliphatic hydrocarbon resin as a tackifier resin ("Quinton G115" manufactured by Zeon Corporation, softening point 115°C, specific gravity 1.03), 30 parts by mass of a polymerized rosin ester resin as a tackifier resin ("Pensel D-160" manufactured by Arakawa Chemical Industries, Ltd., softening point 150°C to 165°C, specific gravity 1.08), 1 part by mass of an antioxidant (tetrakis-[methylene-3-(3'5'-di-t-butyl-4-hydroxyphenyl)propionate]methane, specific gravity 1.15), 60 parts by mass of the filler (1), and toluene (solvent) were uniformly stirred and mixed to obtain a pressure-sensitive adhesive composition 8 having a solids content of 40% by mass.

[0244] 3.Adhesive tape manufacturing [Example 1] The solution of the pressure-sensitive adhesive composition 1 was applied to a release liner ("Film Vina 75E-0010GT" manufactured by Fujimori Kogyo Co., Ltd., hereinafter referred to as release liner (1)) using an applicator so that the thickness after drying would be 10 μm, and then dried at 80° C. for 3 minutes to produce a pressure-sensitive adhesive layer. The pressure-sensitive adhesive layers were attached to both sides of the substrate (1) from which the release liner had been removed, and the layers were laminated under a pressure of 0.2 MPa to produce a pressure-sensitive adhesive tape (1).

[0245] [Example 2] The solution of the pressure-sensitive adhesive composition 2 was applied to a release liner (1) using an applicator so as to have a dry thickness of 50 μm, and then dried at 80° C. for 3 minutes to prepare a pressure-sensitive adhesive layer. The pressure-sensitive adhesive layers were attached to both sides of a substrate (2), and the resulting layers were laminated under a pressure of 0.2 MPa to produce a pressure-sensitive adhesive tape (2).

[0246] [Example 3] The solution of the pressure-sensitive adhesive composition 1 was applied to a release liner (1) using an applicator so as to have a dry thickness of 30 μm, and then dried at 80° C. for 3 minutes to prepare a pressure-sensitive adhesive layer. The pressure-sensitive adhesive layers were attached to both sides of a substrate (2), and the resulting layers were laminated under a pressure of 0.2 MPa to produce a pressure-sensitive adhesive tape (3).

[0247] [Example 4] The solution of the pressure-sensitive adhesive composition 3 was applied to a release liner (1) using an applicator so as to have a dry thickness of 50 μm, and then dried at 80° C. for 3 minutes to prepare a pressure-sensitive adhesive layer. The pressure-sensitive adhesive layers were attached to both sides of a substrate (2), and the resulting layers were laminated under a pressure of 0.2 MPa to produce a pressure-sensitive adhesive tape (4).

[0248] [Example 5] The solution of the pressure-sensitive adhesive composition 4 was applied to a release liner (1) using an applicator so as to have a dry thickness of 30 μm, and then dried at 80° C. for 3 minutes to prepare a pressure-sensitive adhesive layer. The pressure-sensitive adhesive layers were attached to both sides of a substrate (2), and the resulting layers were laminated under a pressure of 0.2 MPa to produce a pressure-sensitive adhesive tape (5).

[0249] [Example 6] The solution of the pressure-sensitive adhesive composition 7 was applied to a release liner (1) using an applicator so as to have a dry thickness of 10 μm, and then dried at 80° C. for 3 minutes to prepare a pressure-sensitive adhesive layer. The pressure-sensitive adhesive layers were attached to both sides of the substrate (1), and the layers were laminated under a pressure of 0.2 MPa to produce a pressure-sensitive adhesive tape (6).

[0250] [Example 7] The solution of the pressure-sensitive adhesive composition 8 was applied to a release liner (1) using an applicator so as to have a dry thickness of 10 μm, and then dried at 80° C. for 3 minutes to prepare a pressure-sensitive adhesive layer. The pressure-sensitive adhesive layers were attached to both sides of a substrate (2), and the resulting layers were laminated under a pressure of 0.2 MPa to produce a pressure-sensitive adhesive tape (7).

[0251] [Comparative Example 1] The solution of the pressure-sensitive adhesive composition 5 was applied to a release liner (1) using an applicator so as to have a dry thickness of 50 μm, and then dried at 80° C. for 3 minutes to prepare a pressure-sensitive adhesive layer. The pressure-sensitive adhesive layers were attached to both sides of the base material (1) from which the release liner had been removed, and the layers were laminated under a pressure of 0.2 MPa to produce a pressure-sensitive adhesive tape (8).

[0252] Comparative Example 2 The solution of the pressure-sensitive adhesive composition 6 was applied to a release liner (1) using an applicator so as to have a dry thickness of 50 μm, and then dried at 80° C. for 3 minutes to prepare a pressure-sensitive adhesive layer. The pressure-sensitive adhesive layers were attached to both sides of the base material (1) from which the release liner had been removed, and the layers were laminated under a pressure of 0.2 MPa to produce a pressure-sensitive adhesive tape (9).

[0253] Comparative Example 3 The solution of the pressure-sensitive adhesive composition 1 was applied to a release liner (1) using an applicator so as to have a dry thickness of 10 μm, and then dried at 80° C. for 3 minutes to prepare a pressure-sensitive adhesive layer. The pressure-sensitive adhesive layers were attached to both sides of a substrate (3), and the layers were laminated under a pressure of 0.2 MPa to produce a pressure-sensitive adhesive tape (10).

[0254] The evaluation results are shown in Tables 1 and 2.

[0255] [Table 1]

[0256] [Table 2]

[0257] From the above results, the pressure-sensitive adhesive tape of the present disclosure exhibited a surface adhesive strength sufficient to temporarily fix an adherend before elongation, but exhibited low surface adhesive strength at the stage of 300% elongation, a significant decrease in surface adhesive strength from before elongation. Therefore, in the low elongation range of the tape, the adherend was easily detachable from the tape. Furthermore, the tape of the present disclosure exhibited excellent releasability (removability 1) when stretched in one go and peeled from the adherend, and even when the stretching was interrupted and then stretched again, the tape was easily peeled off without re-adhering to the adherend (removability 2).

[0258] On the other hand, the tapes of Comparative Examples 1 and 2 had high surface adhesive strength both before stretching and when stretched 300%, and the decrease in surface adhesive strength was small between before stretching and when stretched 300%, making it difficult to detach the tape from the adherend in the low elongation range. Furthermore, the tapes of Comparative Examples 1 and 2 reattached to the adherend when stretching was interrupted and then stretched again. The tape of Comparative Example 3 did not exhibit stretch-peelability due to the lack of extensibility of the substrate. [Explanation of symbols]

[0259] 1...Temporary fixing tape, 2...Base material, 3...Adhesive layer, 5...Component, 200...Transfer receiving body, D...Stretching direction

Claims

1. The adhesive tape has an extensible substrate and a pressure-sensitive adhesive layer containing a filler, The pressure-sensitive adhesive tape has a solubility parameter value of the filler of 8 or more and 20 or less.

2. 2. The adhesive tape according to claim 1, wherein the substrate has a breaking elongation of 200% or more.

3. 3. The adhesive tape according to claim 1, wherein the filler is made of a polymeric material.

4. The pressure-sensitive adhesive tape according to claim 1 or 2, wherein the content of the filler in the pressure-sensitive adhesive layer is 5% by volume or more and 75% by volume or less.

5. 3. The pressure-sensitive adhesive tape according to claim 1, wherein the filler has an average particle size of 0.5 μm or more and 50 μm or less.

6. Surface adhesive strength P when stretched 300% ３００ is 10 N / cm ２ The adhesive tape according to claim 1 or 2, wherein:

7. Surface adhesive strength before stretching P ０ Surface adhesive strength P when stretched 300% ３００ The ratio (P ３００ / P ０ 3. The pressure-sensitive adhesive tape according to claim 1, wherein the value of (a) is 0.5 or less.

8. 3. The pressure-sensitive adhesive tape according to claim 1, wherein the 180° peel adhesive strength is 20 N / 20 mm or less.

9. A method for manufacturing a component using the adhesive tape according to claim 1 or 2, comprising: A method for manufacturing a component, comprising a peeling step of stretching the adhesive tape having one or more components fixed thereto in at least one direction to peel the components from the adhesive tape.

10. The component manufacturing method according to claim 9 , wherein in the peeling step, a jig is pressed against the adhesive tape from the side opposite to the side on which the component is placed, and the adhesive tape is pushed out toward the side on which the component is placed, thereby pulling the adhesive tape.

11. The method for manufacturing a component according to claim 9, further comprising a processing step of processing the component fixed to the adhesive tape.

12. The method for manufacturing a component according to claim 9, further comprising a transfer step of fixing a transfer target to a surface of the component opposite to a surface that contacts the adhesive tape, and stretching the adhesive tape to transfer the component to the transfer target.

13. The surface area of ​​the surface in contact with the adhesive tape per one of the components peeled off in the peeling step is 1 mm ２ 10. The method of claim 9, wherein:

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