Temporarily fixing tape, and production method of component using the temporarily fixing tape

Abstract

To provide: a temporarily fixing tape having a stretch releasable property, capable of fixing and retaining an adherend before stretching, and capable of easily releasing the adherend in a low stretch region in a stretch process; and a production method of a component using the temporarily fixing tape.SOLUTION: A temporary fixing tape of the present disclosure has at least a pressure-sensitive adhesive layer containing a stretched crystalline resin and a polymer of a polymerizable compound, and has any one of the following features. Feature 1: In the pressure-sensitive adhesive layer, a total content of the polymerizable compound and a polymer of the polymerizable compound is 4 pts.mass or more and less than 50 pts.mass based on 100 pts.mass of the stretched crystalline resin. Feature 2: An absolute value of a difference between a 100% modulus and a 300% modulus of the pressure-sensitive adhesive layer is 0.5 or more. Feature 3: The pressure-sensitive adhesive layer has a 100% modulus of 4.5 or less and a 300% modulus of more than 1.0.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a pressure-sensitive adhesive tape (temporary fixing tape) used for temporarily fixing parts, and in particular to a temporary fixing tape that has stretch-releasability, which 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 (a component before processing) is fixed onto adhesive tape, and one or more processed products (components) are produced through processes such as grinding, processing, transport, and chipping by dicing, after which the processed products are peeled off and separated 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 called "temporary fixing tape," "process tape," etc.

[0003] As such a temporary fixing tape, for example, Patent Document 1 discloses a heat-foaming release tape in which heat-expandable balloons in the adhesive layer foam or expand upon heating, thereby reducing adhesive strength. Patent Document 1 discloses a method in which a workpiece is fixed to a heat-foaming release tape, and after processing, heat is applied to the tape 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, thereby reducing adhesive strength. Patent Document 2 also discloses a method in which a workpiece is fixed to an active energy ray-curable release tape, and after processing, UV is irradiated to peel the processed product from the tape. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-229399 [Patent Document 2] Japanese Patent Application Laid-Open No. 2002-121511 Summary of the Invention [Problem to be solved by the invention]

[0005] In manufacturing methods using heat-foaming release tape, the heat applied during tape peeling can cause thermal degradation of the processed product. In particular, in the manufacturing process of MLCCs, applying heat to laminated thin films can easily cause quality problems such as cracking. Furthermore, heat-foaming release tape requires sufficient foaming or expansion of the heat-expandable balloons in the adhesive layer to sufficiently reduce the adhesive strength, which can require time or high heating temperatures. Furthermore, when heat is applied during the processing of the processed product, the heat-expandable balloons in the adhesive layer may foam or expand at a different time than when the processed product is to be released, causing the processed product to detach, making temperature control difficult.

[0006] 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 onto 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.

[0007] The present inventors have discovered a method for temporary fixing without the problems associated with conventional process tapes, which involves using, in place of conventional process tapes, an adhesive tape with so-called stretch-releasing properties (hereinafter sometimes referred to as stretch-releasing tape), which can be stretched (stretched) to be released from an adherend when pulled. However, as a result of further investigation, the present inventors have discovered that when stretch-releasing tape is used in process applications for component manufacturing, particularly when stretch-releasing tape is used in the manufacturing process of micro-sized components such as MLCCs, the following new problems arise.

[0008] First, in conventional applications intended for joining and fixing objects together, the surface area of ​​the adherend (the surface area of ​​the tape side) is relatively large. When stretch-release tape is stretched, the ratio of the area of ​​the adherend that is actually attached to the tape (the adhesive area) to the surface area of ​​the adherend that is on the tape side significantly decreases. This prevents the tape from being stretched too far until the adherend peels and detaches from the tape. However, when the surface area of ​​the adherend that is on the tape side is small, the ratio of the area of ​​the adherend that is actually attached to the tape (the adhesive area) to the surface area of ​​the adherend that is on the tape side is less likely to decrease when stretching the stretch-release tape. This results in excessive tape stretching distances required for the adherend to peel and detach from the tape. These issues become particularly pronounced when the adherend being peeled from the tape is a millimeter- or micro-sized component, such as an MLCC.

[0009] Second, if the adhesive strength of the tape in the low elongation range is reduced in order to shorten the distance the tape must be stretched before the adherend peels off, the initial adhesive strength also decreases, and the tape before elongation is unable to sufficiently secure the adherend. As a result, in the manufacture of parts, when an adherend placed on the tape is subjected to processing such as dicing, the adherend may peel off from the tape or move from its fixed position, making it impossible to process the adherend or reducing processing accuracy.

[0010] The present disclosure has been made in consideration of the above-mentioned circumstances, and provides a temporary fixing tape that has stretch-releasability, is capable of fixing and holding an adherend before stretching, and is capable of easily releasing the adherend in a low elongation range during the stretching process. The present disclosure also provides a method for manufacturing a part using the above-mentioned temporary fixing tape. [Means for solving the problem]

[0011] The present invention has the following aspects. [1] A temporary fixing tape having at least a pressure-sensitive adhesive layer, wherein the pressure-sensitive adhesive layer contains an elongated crystalline resin and a polymer of a polymerizable compound, and the total content of the polymerizable compound and the polymer of the polymerizable compound is 4 parts by mass or more and less than 50 parts by mass per 100 parts by mass of the elongated crystalline resin. [2] A temporary fixing tape having at least a pressure-sensitive adhesive layer, wherein the pressure-sensitive adhesive layer contains an elongated crystalline resin and a polymer of a polymerizable compound, and the absolute value of the difference between the 100% modulus and the 300% modulus of the pressure-sensitive adhesive layer is 0.5 or more. [3] A temporary fixing tape having at least a pressure-sensitive adhesive layer, wherein the pressure-sensitive adhesive layer contains an elongated crystalline resin and a polymer of a polymerizable compound, and the 100% modulus of the pressure-sensitive adhesive layer is 4.5 or less, and the 300% modulus of the pressure-sensitive adhesive layer is greater than 1.0. [4] The temporary fixing tape according to any one of [1] to [3], wherein the polymerizable compound is an active energy ray-curable polymerizable compound. [5] The temporary fixing tape according to any one of [1] to [4], wherein the polymerizable compound is a polyfunctional (meth)acrylate. [6] The temporary fixing tape according to any one of [1] to [5], wherein the stretched crystalline resin is a block copolymer (A') having at least a polymer block A and a polymer block B, and the polymer block B has at least a block containing a structural unit b1 having a crystalline skeleton. [7] The temporary fixing tape according to [6], wherein the structural unit b1 having a crystalline skeleton is a linear hydrocarbon structural unit. [8] The temporary fixing tape according to [6] or [7], wherein the polymer block B further has a block containing a structural unit b2 having a non-crystalline skeleton. [9] The temporary fixing tape according to [8], wherein the structural unit b2 having the amorphous skeleton is a branched hydrocarbon structural unit.

[10] The temporary fixing tape according to any one of [6] to [9], wherein the content of the polymer block B in the block copolymer (A') is 10% by mass to 95% by mass.

[11] The temporary fixing tape according to any one of [6] to

[10] , wherein the polymer block A has an aromatic ring structure.

[12] The temporary fixing tape according to any one of [1] to

[11] , wherein the stretch-induced crystalline resin contains at least one of a styrene-ethylene-butylene-styrene copolymer and a styrene-ethylene-ethylene-propylene-styrene copolymer.

[13] The temporary fixing tape according to any one of [1] to

[12] , wherein the pressure-sensitive adhesive layer further contains a filler.

[14] The temporary fixing tape according to any one of [1] to

[13] , which has the pressure-sensitive adhesive layer on at least one surface of an extensible substrate.

[15] A method for manufacturing a component using the temporary fixing tape according to any one of [1] to

[14] , comprising a peeling step of stretching the temporary fixing tape, to which one or more components are fixed, in at least one direction to peel off the components from the temporary fixing tape.

[16] The surface area of ​​the surface of each part that comes into contact with the temporary fixing tape in the peeling step is 1 mm 2

[15] A method for manufacturing a part according to the following:

[17] The method for manufacturing a component according to

[15] or

[16] , wherein the component is a multilayer ceramic capacitor, a semiconductor element, an inductor, or a chip. [Effects of the Invention]

[0012] The temporary fixing tape of the present disclosure can fix and hold an adherend before stretching, and can easily peel off the adherend in a low elongation range during the stretching process without excessive stretching. The above-mentioned effects can be more pronounced particularly when the adherend is a minute component of millimeter size or less, such as an MLCC.

[0013] Furthermore, according to the component manufacturing method of the present disclosure, the above-described temporary fixing tape is used, and therefore the component can be easily and simply peeled and detached from the tape by stretching the tape, without the need to apply energy such as heat or active energy rays. [Brief explanation of the drawings]

[0014] [Figure 1] 1A to 1C are process diagrams showing an example of a method for manufacturing a component using the temporary fixing tape of the present disclosure. [Figure 2] 1A to 1C are process diagrams showing an example of a method for manufacturing a component using the temporary fixing tape of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0015] The temporary fixing tape of the present disclosure and a method for manufacturing a component using the same will be described below. Note that the temporary fixing tape of the present disclosure may be referred to as the tape of the present disclosure or simply as the tape.

[0016] 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.

[0017] As used herein, "low elongation" refers to a low elongation percentage (elongation), which is the ratio of the length of the tape 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 tensioning when the tape is stretched (elongated). Specifically, a region in which the elongation of the tape is 400% or less, preferably 350% or less, and more preferably 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 a tape when it is pulled, stretched and peeled off (when the tape is elongated) 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)

[0018] In this specification, the "surface area of ​​the side of the adherend (component) that contacts 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. 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 contacts the tape that is actually adhered to the adhesive layer. Before the tape is stretched, the surface area of ​​the adherend (component) that contacts the 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 contacts the tape."

[0019] In this specification, "micro size" refers to a size of millimeter level or less, and particularly refers to a size of millimeter level to micro level. Also, "micro parts" refers to parts of the adherend that are millimeter level or less, and particularly refers to parts of millimeter size to micro size. More specifically, "micro size" and "micro parts" refer to the following: 60384-22:2011). Among them, a micro component refers to a component having a surface area of ​​50 mm 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 0.2 mm is preferable 2 The lower limit of the surface area is not particularly limited, but for example, 0.001 mm 2 More than 0.01 mm, preferably 0.01 mm 2 It can be more than that.

[0020] I. Temporary fixing tape The temporary fixing tape of the present disclosure has at least a pressure-sensitive adhesive layer.

[0021] In aspect 1 of the temporary fixing tape of the present disclosure, the pressure-sensitive adhesive layer comprises an elongated crystalline resin and a polymer of a polymerizable compound, and the total content of the polymerizable compound and the polymer of the polymerizable compound is 4 parts by mass or more and less than 50 parts by mass per 100 parts by mass of the elongated crystalline resin.

[0022] According to the first aspect of the temporary fixing tape of the present disclosure, during the process of stretching the tape, the polymer chains in the stretched crystalline resin are brought into an oriented state where they are gathered together, causing crystallization and significantly increasing the hardness of the pressure-sensitive adhesive layer. Therefore, the adhesive strength in the cleavage direction of the stretched tape (i.e., surface adhesive strength, also referred to as cleavage adhesive strength) can be rapidly reduced. Furthermore, since the stretched crystalline resin is sterically controlled by the polymer of the polymerizable compound within the pressure-sensitive adhesive layer, the elongation rate of the tape can be reduced until the stretched crystalline resin crystallizes. This allows the tape of the present disclosure to achieve both good adhesion before stretching and good releasability in the low elongation region during the stretching process. Further preferred ranges for the content of the polymerizable compound and the polymer of the polymerizable compound will be described later.

[0023] In a second aspect of the tape of the present disclosure, the adhesive layer comprises an elongated crystalline resin and a polymer of a polymerizable compound, and the absolute value of the difference between the 100% modulus and the 300% modulus of the adhesive layer is 0.5 or more.

[0024] According to the second aspect of the tape of the present disclosure, the adhesive layer contains a polymer of an elongated crystalline resin and a polymerizable compound, and the absolute value of the difference between the 100% modulus and the 300% modulus is equal to or greater than a predetermined value. Therefore, before elongation, the tape exhibits sufficient adhesive strength for temporary fixation of an adherend. However, when the tape is stretched, the adhesive strength drops sharply in the low elongation range. Therefore, the tape of the present disclosure achieves both good adhesiveness before elongation and good releasability in the low elongation range during elongation. A more preferable range for the absolute value of the difference between the 100% modulus and the 300% modulus is described below.

[0025] In a third aspect of the tape of the present disclosure, the adhesive layer comprises an elongated crystalline resin and a polymer of a polymerizable compound, and the 100% modulus of the adhesive layer is 4.5 or less, and the 300% modulus of the adhesive layer is greater than 1.0.

[0026] According to the third aspect of the tape of the present disclosure, the adhesive layer contains a polymer of an elongated crystalline resin and a polymerizable compound, and the 100% modulus and 300% modulus are each within a predetermined range. Therefore, before elongation, the adhesive layer exhibits sufficient adhesive strength for temporary fixation of an adherend. However, when the tape is stretched, the adhesive strength rapidly decreases in the low elongation range. Therefore, the tape of the present disclosure can achieve both good adhesiveness before elongation and good releasability in the low elongation range during the elongation process. More preferred ranges for the 100% modulus and 300% modulus are described below. The tape of the present disclosure is described in detail below.

[0027] 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 This is particularly effective for the following micro-components:

[0028] 1. Adhesive layer The pressure-sensitive adhesive layer of the present disclosure is not limited in composition, etc., as long as the tape and pressure-sensitive adhesive layer of the present disclosure can exhibit the desired physical properties. In particular, the pressure-sensitive adhesive layer preferably contains at least an extended crystalline resin (A) and a polymer (B) of a polymerizable compound (B').

[0029] (1) Elongated crystalline resin (A) The strain-induced crystalline resin (A) in the pressure-sensitive adhesive layer is the base polymer that constitutes the pressure-sensitive adhesive. Here, the strain-induced crystalline resin refers to a resin that has the property that when stretched, the polymer chains stretched in the stretching direction gather together to form a crystalline structure, and refers to a resin with a regular molecular structure that is prone to forming a crystalline structure. A regular molecular structure refers to a structure in which each monomer unit tends to have asymmetric carbons with the same configuration along the chain, such as in polyethylene or polypropylene. The presence of such strain-induced crystallinity can be identified by a tensile test. Specifically, it can be identified by a low 100% modulus (e.g., 5 MPa or less) and a high breaking stress relative to the 100% modulus (e.g., 15 MPa or more).

[0030] The stretched crystalline resin (A) may be, for example, a block copolymer having at least a polymer block A and a polymer block B, wherein the polymer block B has at least a block containing a structural unit b1 having a crystalline skeleton. The block copolymer that can be used as the stretched crystalline resin (A) may be referred to as a block copolymer (A').

[0031] (Block copolymer (A')) The block copolymer (A') has at least a polymer block A and a polymer block B, and the polymer block B has at least a block containing a structural unit b1 having a crystalline skeleton. The block copolymer (A') may be composed of the polymer block A and a polymer block B containing a block containing the structural unit b1. It is preferable that the polymer block A is a hard block and the polymer block B is a soft block.

[0032] Furthermore, the block copolymer (A') may have the polymer block A and a polymer block B having a block containing the structural unit b1, and a polymer block C different from the polymer blocks A and B. When the block copolymer (A') has polymer blocks A, B, and C, it is preferable that the polymer block B is located between the polymer block A and the polymer block C. When the block copolymer (A') has the polymer blocks A, B, and C, it is preferable that the polymer block B is a midblock phase located between the polymer blocks A and C, and it is preferable that the polymer blocks A and C are endblock phases. It is also preferable that the polymer blocks A and C are hard blocks, and the polymer block B is a soft block.

[0033] The block copolymer (A') can be, for example, A diblock copolymer represented by polymer block A and polymer block B. Triblock copolymers represented by polymer block A-polymer block B-polymer block A, polymer block A-polymer block B-polymer block C, etc. Tetrablock copolymers represented by polymer block A-polymer block B-polymer block A-polymer block B, polymer block A-polymer block B-polymer block C-polymer block B, etc. Examples include pentablock copolymers represented by polymer block A-polymer block B-polymer block A-polymer block B-polymer block C, polymer block A-polymer block B-polymer block C-polymer block B-polymer block C, etc. Among these, a diblock copolymer represented by polymer block A-polymer block B, or a triblock copolymer represented by polymer block A-polymer block B-polymer block A or polymer block A-polymer block B-polymer block C is preferred.

[0034] (Polymer block B) The polymer block B contains at least a block containing a structural unit b1 having a crystalline skeleton. Because the polymer block B in the block copolymer (A') contains a block containing a structural unit b1 having a crystalline skeleton, the polymer chains are brought together and oriented upon elongation, forming a crystalline structure. The block copolymer (A') contained in the pressure-sensitive adhesive layer contains a polymer block B with such a specific structure, and as the pressure-sensitive adhesive layer is stretched, the block containing the structural unit b1 in the polymer block B forms a crystalline structure, resulting in a phase transition. This increases the hardness of the pressure-sensitive adhesive layer, reducing surface adhesion and allowing for easy peeling from the adherend.

[0035] The structural unit b1 having a crystalline skeleton is not particularly limited as long as it is a structural unit that can form a crystalline structure by elongation, and examples thereof include linear hydrocarbon structural units. Among these, linear aliphatic hydrocarbon structures are preferred. When the structural unit b1 having a crystalline skeleton is a linear hydrocarbon structural unit, the number of carbon atoms in the linear hydrocarbon constituting the structural unit b1 is not particularly limited, and can be, for example, 20 or less carbon atoms, preferably 10 or less, and more preferably 8 or less carbon atoms. The number of carbon atoms is 2 or more, and preferably 4 or more.

[0036] In the polymer block B, an example of a block containing the structural unit b1 is a linear polyolefin block. The block containing the structural unit b1 may be any block as long as it contains the structural unit b1 as a main component, and is preferably a block consisting of the structural unit b1.

[0037] The content of the structural unit b1 having a crystalline skeleton in the polymer block B is preferably 10% by mass to 95% by mass, more preferably 30% by mass to 90% by mass, and even more preferably 60% by mass to 85% by mass.

[0038] The polymer block B preferably has a block containing structural units b2 having an amorphous skeleton in addition to the block containing structural units b1 having a crystalline skeleton. An amorphous skeleton has the property of not forming a crystalline structure due to the polymer chains stretched in the stretching direction when stretched, and has an irregular molecular structure. An irregular molecular structure is, for example, a structure in which asymmetric carbons in the main chain tend to have multiple different configurations. Specific examples include polycarbonate and polymethyl methacrylate resin.

[0039] The polymer block B having the block containing the structural unit b1 having the crystalline skeleton and the block containing the structural unit b2 having the amorphous skeleton can be represented by, for example, the following formula (I).

[0040] [ka]

[0041] (In the above formula, b1 represents a structural unit having a crystalline skeleton, b2 represents a structural unit having a non-crystalline skeleton, j and l each independently represent an integer greater than 0, and k represents an integer greater than or equal to 0.) In the above formula, when k is 0, the polymer block B is composed of structural units b1.

[0042] When the polymer block B has a block containing a structural unit b1 having a crystalline skeleton and a block containing a structural unit b2 having a non-crystalline skeleton, the structural unit b1 can form a crystalline texture (crystal structure) by elongation, and the structural unit b2 can improve extensibility. The structural units b1, to which extensibility is imparted by the structural unit b2 of the polymer block B, become gathered together in an oriented state during elongation, forming a crystalline texture (crystal structure), and a phase transition occurs. This increases the hardness of the pressure-sensitive adhesive layer, reduces the surface adhesion, and allows for easy peeling from the adherend.

[0043] The structural unit b2 having an amorphous skeleton is not particularly limited as long as it is a structural unit that does not form a crystalline texture (crystalline structure) upon elongation, and examples thereof include branched hydrocarbon structural units. Among these, branched aliphatic hydrocarbon structural units are preferred. The number of carbon atoms in the branched hydrocarbon constituting the structural unit b2 is not particularly limited, but can be, for example, 20 or less carbon atoms, preferably 10 or less, and more preferably 8 or less carbon atoms. The number of carbon atoms is 2 or more, preferably 4 or more. An example of a block containing the structural unit b2 in such polymer block B is a branched polyolefin block. The block containing the structural unit b2 may be a block consisting of the structural unit b2, as long as the structural unit b2 is the main component, and is preferably a block consisting of the structural unit b2.

[0044] The polymer block B preferably has a block containing a linear hydrocarbon structural unit b1 and a block containing a branched hydrocarbon structural unit b2.

[0045] The polymer block B preferably contains no unsaturated double bonds. The amount of remaining unsaturated double bonds is preferably 50 mol % or less, more preferably 30 mol % or less, even more preferably 10 mol % or less, still more preferably 5 mol % or less, and particularly preferably 0 mol %. The amount of remaining unsaturated double bonds in the polymer block B can be determined by measuring the iodine value before and after hydrogenation.

[0046] The content of polymer block B in the block copolymer (A') is preferably 10% by mass to 95% by mass, more preferably 30% by mass to 90% by mass, and even more preferably 60% by mass to 85% by mass. When the content of polymer block B in the block copolymer (A') is within the above range, the block copolymer (A') is provided with extensibility, and during the elongation process, structural units b1 having a crystalline skeleton of the polymer block B gather together and become oriented, thereby causing a phase transition, which can rapidly increase the hardness of the pressure-sensitive adhesive layer and reduce the surface adhesive strength.

[0047] (Polymer blocks A and C) The polymer blocks A and C may each independently have, as a structural unit, an olefin such as propylene, urethane, an aromatic polyester such as PBT, polyamide, a methacrylic acid ester, an aromatic vinyl compound such as styrene, or the like.

[0048] In particular, the polymer block A preferably has a ring structure, more preferably an aromatic ring structure. Furthermore, when the block copolymer (A') contains the polymer blocks A and C, the polymer blocks A and C each independently preferably have a ring structure, more preferably an aromatic ring structure. This can increase the cohesive strength of the pressure-sensitive adhesive layer, making the pressure-sensitive adhesive layer less likely to tear during the process of stretching the tape and the pressure-sensitive adhesive layer, and can also suppress the occurrence of adhesive residue on the adherend when the adherend is peeled off and detached from the tape.

[0049] (Block copolymer (A')) The weight-average molecular weight of the block copolymer (A') can be appropriately selected depending on the type of block copolymer, but is preferably 50,000 to 500,000, more preferably 60,000 to 400,000, and even more preferably 70,000 to 300,000. Among these, it is preferable that the block copolymer is a styrene-based block copolymer, and that the weight-average molecular weight of the styrene-based block copolymer is within the above range. The weight-average molecular weight of the block copolymer (A') is a polystyrene-equivalent value measured by gel permeation chromatography (GPC) testing. (GPC Measurement Apparatus and Measurement Conditions) Apparatus: GPC apparatus "GPC-8020" (manufactured by Tosoh Corporation) Separation column: Column "TSKgel Super HM-N (manufactured by Tosoh Corporation)" Eluent: tetrahydrofuran Eluent flow rate: 150μL Flow rate: 1ml / min Sample concentration: 5mg / 10cc Column temperature: 40℃ Calibration curve: Created using standard polystyrene

[0050] The block copolymer (A') preferably has a Shore hardness A (type A) of at least 50 and a Shore hardness D (type D) of at most 75, more preferably a Shore hardness A (type A) of at least 55 and a Shore hardness D (type D) of at most 65, and even more preferably a Shore hardness A (type A) of at least 60 and a Shore hardness D (type D) of at most 60. When the Shore hardness of the block copolymer (A') is within the above range, it is easy to obtain suitable adhesive strength for the pressure-sensitive adhesive layer, and the high cohesive force makes it easy to suppress adhesive residue when peeling the tape from the adherend.

[0051] The Shore hardness of the block copolymer (A') is a Type A hardness or Type D hardness value measured according to the method described in "Rubber Hardness" in the Examples section below, using a durometer (spring-type rubber durometer, model GS-719G, manufactured by Teclock Corporation) or a durometer (spring-type rubber durometer, model GS-720G, manufactured by Teclock Corporation) in accordance with JIS K 6253. More specifically, Shore hardness A (Type A) is a value measured according to JIS K 6253 using a durometer (spring-type rubber durometer, model GS-719G, manufactured by Teclock Corporation), and Shore hardness D (Type D) is a value measured according to JIS K 6253 using a durometer (spring-type rubber durometer, model GS-720G, manufactured by Teclock Corporation). The Shore hardness is measured after 15 seconds or more have elapsed since a load was applied to a test piece sheet of the block copolymer (A').

[0052] The Shore hardness of the block copolymer (A') can be adjusted by the content ratio and density of the polymer blocks A and C (hard domains) in the block copolymer (A').

[0053] The pressure-sensitive adhesive layer contains an elongated crystalline resin (preferably block copolymer (A')) as a base polymer. The content of the elongated crystalline resin (block copolymer (A')) in the pressure-sensitive adhesive layer is preferably 5% by mass or more and 60% by mass or less, more preferably 10% by mass or more and 55% by mass or less, and even more preferably 20% by mass or more and 50% by mass or less, based on 100% by mass of the pressure-sensitive adhesive layer (solid content of the pressure-sensitive adhesive composition). By ensuring that the content of the elongated crystalline resin (block copolymer (A')) in the pressure-sensitive adhesive layer falls within the above range, suitable adhesive strength is easily obtained, and adhesive residue can be reduced when the tape is stretched and peeled off the adherend.

[0054] Furthermore, the pressure-sensitive adhesive layer may contain, as a base polymer, a polymer other than the stretch-strained crystalline resin (block copolymer (A')) in addition to the stretch-strained crystalline resin (block copolymer (A')). Examples of polymers other than the stretch-strained crystalline resin (block copolymer (A')) include resins that do not have stretch-strained crystallinity (non-stretch-strained crystalline resins), and specific examples include diblock copolymers and block copolymers that do not have the polymer block B. More specific examples of the non-stretch-strained crystalline resins include styrene-ethylene-propylene copolymer (SEP) and styrene-ethylene-propylene-styrene copolymer (SEPS).

[0055] For example, the base polymer of the pressure-sensitive adhesive layer may contain an extension-strain crystalline resin (block copolymer (A')) selected from the group consisting of styrene-ethylene-butylene-styrene copolymer (SEBS) and styrene-ethylene-ethylene-propylene-styrene copolymer (SEEPS), and a non-extension-strain crystalline resin selected from the group consisting of styrene-ethylene-propylene copolymer (SEP) and styrene-ethylene-propylene-styrene copolymer (SEPS). SEBS and SEEPS are extension-strain crystalline resins due to their molecular structure, while SEP and SEPS are non-extension-strain crystalline resins that do not have extension-strain crystallinity due to their molecular structure.

[0056] The proportion of the stretch-strain crystalline resin (block copolymer (A')) in the total amount of the base polymer is preferably 30% by mass or more, more preferably 40% by mass or more, even more preferably 50% by mass or more, and particularly preferably 60% by mass or more. When the proportion of the stretch-strain crystalline resin (block copolymer (A')) in the total amount of the base polymer is within the above range, it is possible to prevent the presence of other polymers from impairing the functions provided by the structure of the block copolymer (A'). The upper limit of the proportion of the stretch-strain crystalline resin (block copolymer (A')) in the total amount of the base polymer is 100% by mass, i.e., the base polymer is entirely a stretch-strain crystalline resin.

[0057] The content of the base polymer in the adhesive layer is not particularly limited as long as the adhesive function of the base polymer can be exhibited, but is preferably 10% by mass or more and 70% by mass or less, more preferably 30% by mass or more and 60% by mass or less, and even more preferably 35% by mass or more and 55% by mass or less, based on 100% by mass of the adhesive layer (solid matter of the adhesive composition).

[0058] The block copolymer (A') may be a thermoplastic elastomer having a block structure. Examples include styrene-based block copolymers (soft segment: polybutadiene, polyisoprene, etc. / hard segment: polystyrene), olefin-based block copolymers (soft segment: ethylene-propylene rubber / hard segment: polypropylene), polyurethane-based block copolymers (soft segment: polyether, polyester / hard segment: polyurethane), polyester-based block copolymers (soft segment: polyether / hard segment: polyester), polyamide-based block copolymers (soft segment: polypropylene glycol, polytetramethylene ether glycol, or polyester, polyether / hard segment: polyamide (nylon resin)), polybutadiene-based block copolymers (soft segment: amorphous butyl rubber / hard segment: syndiotactic 1,2-polybutadiene resin), and acrylic-based block copolymers (soft segment: polyacrylic ester / hard segment: polymethyl methacrylate).

[0059] Among these, the block copolymer (A') is preferably one or more block copolymers selected from the group consisting of styrene-based block copolymers, urethane-based block copolymers, acrylic-based block copolymers, and polyester-based block copolymers, and styrene-based block copolymers are preferred from the viewpoint of ease of adjusting the blend composition using commercially available raw materials, such as being likely to exhibit good compatibility with a tackifier used to adjust the adhesive strength of the adhesive layer.

[0060] The block copolymer (A') contained in the pressure-sensitive adhesive layer may be one type alone or two or more types. The pressure-sensitive adhesive layer may contain two or more types of block copolymers, for example, the block copolymer (A') may contain one or two or more types of styrene-based block copolymer (A1) and non-styrene-based block copolymer. The block copolymer may also contain two or more block copolymers of the same type but different structures. For example, if the block copolymer is a styrene-based block copolymer (A1), it may contain a styrene-based block copolymer (A11) and a styrene-based block copolymer (A12) having a structure different from that of the styrene-based block copolymer (A11).

[0061] (styrene-based block copolymer) When the block copolymer (A') is a styrene-based block copolymer (A1), the styrene-based block copolymer (A1) preferably has polymer block A having structural units (a1) derived from an aromatic vinyl compound, and polymer block B having structural units (a2) derived from a hydrogenated conjugated diene compound. When the styrene-based block copolymer (A1) has polymer blocks A, B, and C, the polymer block C preferably has polymer block A having structural units (a1) derived from an aromatic vinyl compound, independently. In the styrene-based block copolymer (A1), the structural units (a1) derived from an aromatic vinyl compound form hard domains, and the structural units (a2) derived from a hydrogenated conjugated diene compound form soft domains.

[0062] The polymer block B in the styrene-based block copolymer (A1) may contain at least the linear structural unit (a2-1) derived from a hydrogenated conjugated diene compound, but preferably contains the linear structural unit (a2-1) derived from a hydrogenated conjugated diene compound and the branched structural unit (a2-1) derived from a hydrogenated conjugated diene compound. In this case, the polymer block B has a random polymer block (random copolymer structure) of the linear structural unit (a2-1) derived from a hydrogenated conjugated diene compound and the branched structural unit (a2-1) derived from a hydrogenated conjugated diene compound.

[0063] The structural unit derived from a hydrogenated conjugated diene compound refers to a structural unit derived from a conjugated diene compound in which the double bond has been hydrogenated. The conjugated diene compound before hydrogenation is a diolefin having conjugated double bonds. In other words, the styrene-based block copolymer (A1) can be a block copolymer in which polymer blocks A and C each independently have structural units (a1) derived from an aromatic vinyl compound, and polymer block B has at least structural units (a2-1) derived from a linear polyolefin. Of these, a block copolymer in which polymer block B has structural units (a2-1) derived from a linear polyolefin and structural units (a2-2) derived from a branched polyolefin is preferred.

[0064] -Structural unit (a1)- Examples of aromatic vinyl compounds constituting the structural unit (a1) derived from the aromatic vinyl compound 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, N,N-diethyl-p-aminoethylstyrene, etc. The aromatic vinyl compounds may be used alone or in combination of two or more.

[0065] In particular, the structural unit (a1) is preferably derived from an aromatic vinyl compound selected from styrene, α-methylstyrene, and 4-methylstyrene, and more preferably derived from styrene. That is, each of the polymer blocks A and C preferably has a structural unit (a1) derived from styrene represented by the following chemical formula (II):

[0066] [ka]

[0067] The content of the structural unit (a1) derived from an aromatic vinyl compound in the styrene-based block copolymer (A1) is preferably 20% to 80% by mass, more preferably 22% to 50% by mass, more preferably 25% to 40% by mass, and even more preferably 28% to 35% by mass, based on the total amount of the styrene-based block copolymer (A1). By containing the structural unit (a1) derived from an aromatic vinyl compound in the above range, the styrene-based block copolymer (A1) can increase the cohesive strength of the pressure-sensitive adhesive layer, making the pressure-sensitive adhesive layer less likely to tear during the process of stretching the tape and the pressure-sensitive adhesive layer, and suppressing the occurrence of adhesive residue on the adherend when the adherend is peeled off and detached from the tape.

[0068] -Structural unit (a2)- The structural unit derived from a hydrogenated conjugated diene compound refers to a structural unit in which the double bond in the structural unit derived from a conjugated diene compound is hydrogenated. The conjugated diene compound before hydrogenation is a diolefin having a conjugated double bond. The structural unit derived from a hydrogenated conjugated diene compound preferably has 4 to 20 carbon atoms, more preferably 4 to 10 carbon atoms, and even more preferably 4 to 8 carbon atoms. Examples of the conjugated diene compound constituting such a structural unit derived from a hydrogenated 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, and 1,3-cyclohexadiene. , 2-methyl-1,3-octadiene, 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.

[0069] When the polymer block B in the styrene-based block copolymer (A1) has a linear structural unit (a2-1) derived from a hydrogenated conjugated diene compound and a branched structural unit (a2-2) derived from a hydrogenated conjugated diene compound, it is preferable that the conjugated diene before hydrogenation contains two or more types.

[0070] The linear structural unit (a2-1) can be appropriately selected from the above conjugated diene compounds that can assume a linear structure by hydrogenation. Among them, 1,3-butadiene, 1,3-pentadiene, 1,3-hexadiene, 2,4-hexadiene, and 1,3-octadiene are preferred, and 1,3-butadiene is particularly preferred.

[0071] The branched structural unit (a2-2) can be appropriately selected from the above conjugated diene compounds that can have a branched structure by hydrogenation, among which 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-cyclohexadiene, 2-methyl-1,3-octadiene, 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-cyclohexadiene, 3-methyl-1,3-hexadiene, 2-benzyl-1,3-butadiene, and 2-p-tolyl-1,3-butadiene are preferred, and isoprene is particularly preferred.

[0072] -Polymer block B- In the polymer block B, the hydrogenation rate (hydrogenation rate) of the linear structural unit (a2-1) and the branched structural unit (a2-2) is preferably 80 mol % or more, more preferably 90 mol % or more, even more preferably 95 mol % or more, and particularly preferably substantially 100 mol % of the carbon-carbon double bonds based on the conjugated diene compound units. When the hydrogenation rates of the linear structural unit (a2-1) and the branched structural unit (a2-2) in the polymer block B are within the above ranges, the pressure-sensitive adhesive layer becomes hard in the low elongation range of the tape and the pressure-sensitive adhesive layer, and the surface adhesive strength and surface tackiness can be reduced. The hydrogenation rate of the carbon-carbon double bonds in the polymer block B is measured by nuclear magnetic resonance spectroscopy ( 1 H-NMR spectroscopy) before and after hydrogenation, and the hydrogenation rate is obtained from the measured values.

[0073] The polymer block B may contain a structural unit derived from a polymerizable monomer other than the conjugated diene compound, as long as it does not impair the effects of the present invention. Examples of the other polymerizable monomer include at least one selected from aromatic vinyl compounds such as styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, pt-butylstyrene, 2,4-dimethylstyrene, vinylnaphthalene, and vinylanthracene, methyl methacrylate, methyl vinyl ether, N-vinylcarbazole, β-pinene, 8,9-p-menthene, dipentene, methylenenorbornene, and 2-methylenetetrahydrofuran.

[0074] When polymer block B contains a structural unit derived from a polymerizable monomer other than a conjugated diene compound, the content thereof is more preferably 20% by mass or less, further preferably 10% by mass or less, and even more preferably 5% by mass or less, based on the total mass of polymer block B.

[0075] -Styrene-based block copolymer (A1)- Specifically, the styrene-based block copolymer (A1) preferably used is a styrene-ethylene-butylene-styrene copolymer (SEBS) or a styrene-ethylene-ethylene-propylene-styrene copolymer (SEEPS).

[0076] The weight-average molecular weight (Mw) of the styrene block copolymer (A1) is preferably from 50,000 to 500,000, more preferably from 60,000 to 400,000, even more preferably from 65,000 to 300,000, and particularly preferably from 70,000 to 250,000. When the pressure-sensitive adhesive layer contains two or more types of styrene block copolymers (A1), it is preferable that the Mn of at least one type of styrene block copolymer (A1) is within the above range, and it is more preferable that the Mn of all of the styrene block copolymers (A1) is within the above range.

[0077] The molecular weight distribution (Mw / Mn), which is the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of the styrene block copolymer (A1), is not particularly limited, but is, for example, preferably greater than 1.0 and not greater than 1.5, more preferably greater than 1.0 and not greater than 1.3, even more preferably greater than 1.0 and not greater than 1.2, and particularly preferably greater than 1.0 and not greater than 1.1. When the pressure-sensitive adhesive layer contains two or more types of styrene block copolymers (A1), it is preferable that the Mw / Mn of at least one type of styrene block copolymer (A1) is within the above range, and it is more preferable that the Mw / Mn of all of the styrene block copolymers (A1) is within the above range.

[0078] The number average molecular weight (Mn) and weight average molecular weight (Mw) of the styrene-based block copolymer (A1) are values ​​determined by gel permeation chromatography (GPC) in terms of standard polystyrene, and the molecular weight distribution (Mw / Mn) is a value calculated from the above Mw and Mn values. Apparatus: GPC-8020 (Tosoh Corporation) Solvent: tetrahydrofuran Measurement temperature: 40℃ Flow rate: 1mL / min Injection volume: 150μL, concentration: 5mg / 10cc (block copolymer / THF)

[0079] When the pressure-sensitive adhesive layer contains a styrene-based block copolymer (A1), it may or may not contain a styrene-based block copolymer other than the styrene-based block copolymer (A1) in addition to the styrene-based block copolymer (A1). Examples of the styrene-based block copolymer other than the styrene-based block copolymer (A1) include a styrene-based diblock copolymer and a styrene-based triblock copolymer other than the styrene-based block copolymer (A1). Specific examples include a styrene-isoprene block copolymer, a styrene-isoprene-styrene block copolymer, a styrene-isoprene-butadiene-styrene block copolymer, a styrene-butadiene-styrene block copolymer, a styrene-ethylene-butylene block copolymer, a styrene-ethylene-propylene block copolymer, and hydrogenated versions of these copolymers. These may be used alone or in combination. It is particularly preferred that the styrene-based block copolymer other than the styrene-based block copolymer (A1) be a styrene-based diblock copolymer.

[0080] When the pressure-sensitive adhesive layer contains the styrene block copolymer (A1) and a styrene block copolymer other than the styrene block copolymer (A1), the content of the styrene block copolymer other than the styrene block copolymer (A1) in the pressure-sensitive adhesive layer (solid content of the pressure-sensitive adhesive composition) is preferably 50% by mass or less, more preferably 40% by mass or less, more preferably 30% by mass or less, and even more preferably 20% by mass or less. The lower limit of the content of the styrene block copolymer other than the styrene block copolymer (A1) in the pressure-sensitive adhesive layer is 0% by mass.

[0081] (2) Polymerizable compound (B') and polymer (B) of polymerizable compound (B') The pressure-sensitive adhesive layer contains at least one of a polymerizable compound (B') and a polymer (B) of the polymerizable compound (B'). By containing at least one of the polymerizable compound (B') and the polymer (B) of the polymerizable compound (B'), the cohesive strength of the pressure-sensitive adhesive layer can be increased, preventing stringiness when the tape is stretched to peel it from the adherend, and facilitating peeling. This improves releasability in the low elongation range. The polymer (B) of the polymerizable compound (B') is different from and distinct from the polymers constituting the base polymer and filler described above.

[0082] The pressure-sensitive adhesive layer containing at least one of the polymerizable compound (B') and the polymer (B) of the polymerizable compound (B') can be formed, for example, by a method of applying a pressure-sensitive adhesive composition containing at least the stretched crystalline resin (A) and the polymerizable compound (B') to a release liner or a substrate, and irradiating the coating film of the pressure-sensitive adhesive composition with active energy rays such as light to polymerize the polymerizable compound, or by a method of heating the coating film of the pressure-sensitive adhesive composition to polymerize the polymerizable compound.

[0083] The pressure-sensitive adhesive layer preferably contains at least a polymer (B) of a polymerizable compound (B'). The coexistence of the stretch-strained crystalline resin (A) and the polymer (B) of the polymerizable compound (B') in the pressure-sensitive adhesive layer enhances the steric control effect of the polymer (B) of the polymerizable compound (B') on the stretch-strained crystalline resin (A), effectively reducing the elongation rate of the tape until the stretch-strained crystalline resin crystallizes. The pressure-sensitive adhesive layer contains the polymer (B) of the polymerizable compound (B'), but may also contain unreacted polymerizable compound (B'). The proportion of the polymer (B) in the total content of the polymerizable compound (B') and its polymer (B) 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 100% by mass. By setting the proportion of the polymer (B) in the total weight of the polymerizable compound (B') and its polymer (B) within the above range, it is possible to suppress an undesired increase in the adhesion strength between the pressure-sensitive adhesive layer and the adherend due to the presence of unreacted polymerizable compound (B'), and to suppress the occurrence of the adhesion enhancement phenomenon in which the adhesive strength increases over time.

[0084] The polymerizable compound (B') constituting the polymer (B) is not particularly limited as long as it can bond upon application of energy, and examples thereof include low molecular weight compounds (monomers, oligomers, copolymers, etc.) with an average molecular weight of about 1,000. Examples of such polymerizable compounds (B') include active energy ray-polymerizable compounds that can be polymerized by irradiation with active energy rays such as light, and thermally polymerizable compounds that can be polymerized by heat. Among these, active energy ray-polymerizable compounds are preferred because they are easy to use to obtain dense polymers with high crosslink density and are excellent at significantly reducing the adhesive strength of the adhesive surface of the tape when the tape is stretched and peeled off the adherend.

[0085] The active energy ray polymerizable compound is not particularly limited as long as it can form a polymer by irradiation with active energy rays. Examples of the active energy ray polymerizable compound include polyester-based, acrylic-based, urethane-based, amide-based, silicone-based, and epoxy-based monomers, oligomers, and copolymers. These can be used alone or in combination of two or more.

[0086] The active energy ray-polymerizable compound is preferably a compound having two or more polymerizable unsaturated double bonds in one molecule, and is preferably a polyfunctional monomer and / or oligomer having two or more (preferably 2 to 6, more preferably 3 to 6) active energy ray-polymerizable functional groups in one molecule. Examples of the active energy ray-polymerizable functional group include ethylenically unsaturated bond-containing groups such as vinyl groups, allyl groups, and (meth)acryloyl groups. As the active energy ray-polymerizable functional group, a plurality of the same functional groups may be used, or two or more types of functional groups may be used.

[0087] Among these, the active energy ray-polymerizable compound preferably contains at least a polyfunctional (meth)acrylate, and more preferably the active energy ray-polymerizable compound is a polyfunctional (meth)acrylate. That is, the pressure-sensitive adhesive layer preferably contains at least one of a polyfunctional (meth)acrylate and a polymer of a polyfunctional (meth)acrylate, and more preferably contains a polymer of a polyfunctional (meth)acrylate. This is because a polymer of a polyfunctional (meth)acrylate (particularly a polymer of a polyfunctional (meth)acrylate having three or more functional groups) can have a network structure and has a high effect of stereocontrolling the elongated crystalline resin.

[0088] The polyfunctional (meth)acrylate may be used alone or in combination of two or more. Examples of the polyfunctional (meth)acrylate include polyethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, 1,2-ethanediol di(meth)acrylate, 1,2-propanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, neopentyl glycol hydroxypivalate di(meth)acrylate, triptych di(meth)acrylate, tetraisopropyl ... Examples of the acrylate include (meth)acrylates such as pyrene glycol di(meth)acrylate, trimethylolpropane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, tris(2-acryloyloxy)isocyanurate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, di(trimethylolpropane)tetra(meth)acrylate, di(pentaerythritol)penta(meth)acrylate, and di(pentaerythritol)hexa(meth)acrylate; and (meth)acrylate esters of sugar alcohols such as sorbitol.

[0089] Further, examples of polyfunctional (meth)acrylates include urethane acrylate, polyester acrylate, and epoxy acrylate.

[0090] The number of functional groups in the polyfunctional (meth)acrylate is not particularly limited, but is preferably 2 or more, and more preferably 3 or more, since the polymer network structure enhances the effect of stereocontrol on the elongated crystalline resin. The upper limit of the number of functional groups is not particularly limited, but can be 10 or less, preferably 6 or less, and more preferably 5 or less. The polyfunctional (meth)acrylate can also have other functional groups such as hydroxyl groups to the extent that the effect is not impaired.

[0091] The thermally polymerizable compound is preferably a compound that is non-reactive at room temperature but undergoes a crosslinking reaction, polymerization reaction, polycondensation reaction, or polyaddition reaction at a temperature of, for example, 100°C or higher (preferably 150°C or higher). Examples of the thermally polymerizable compound include monomers, oligomers, and copolymers of polyurethane, acrylic-urethane, acrylic-styrene, fluororesin, acrylic silicone, acrylic, polyester, polyolefin, melamine, benzoguanamine, epoxy, oxetane, phenol, and benzoxazine. Examples of the thermally polymerizable compound that can be used include blocked isocyanates, carbodiimides, and silane coupling agents.

[0092] The molecular weight of the polymerizable compound (B') is preferably from 100 to 3,000, more preferably from 150 to 1,000, more preferably from 150 to 1,000, and even more preferably from 200 to 500, from the viewpoints of compatibility with other resin components (such as stretched crystalline resins and tackifying resins) that form the adhesive layer and ensuring safety to the human body while being in a liquid state that is easy for workers to handle. The weight average molecular weight of the polymer (B) of the polymerizable compound (B') is a value (polystyrene equivalent) based on measurement by GPC (gel permeation chromatography).

[0093] The total content of the polymerizable compound (B') and the polymer (B) of the polymerizable compound (B') in the pressure-sensitive adhesive layer is preferably 4 to less than 50 parts by weight, more preferably 10 to 45 parts by weight, even more preferably 15 to 40 parts by weight, and particularly preferably 20 to 35 parts by weight, per 100 parts by weight of the stretch-strained crystalline resin (A). When the total content of the polymerizable compound (B') and its polymer (B) per 100 parts by weight of the stretch-strained crystalline resin (A) falls within the above range, the polymerizable compound (B') and its polymer (B) effectively exert their stereoregulatory function on the stretch-strained crystalline resin (A), effectively reducing the tape elongation rate until the stretch-strained crystalline resin (A) crystallizes, thereby significantly reducing adhesive strength even in the low elongation range. In particular, the content of the polymer (B) of the polymerizable compound (B') in the pressure-sensitive adhesive layer per 100 parts by weight of the stretch-strained crystalline resin (A) is preferably within the above range. In this case, it is preferred that the polymerizable compound (B') is entirely present as a polymer (B) in the pressure-sensitive adhesive layer.

[0094] The total content of the polymerizable compound (B') and its polymer (B) in the pressure-sensitive adhesive layer is preferably 1.5% by mass to 20% by mass, more preferably 5% by mass to 15% by mass, and even more preferably 10% by mass to 14% by mass, based on 100% by mass of the pressure-sensitive adhesive layer (solid content of the pressure-sensitive adhesive composition). When the total content of the polymerizable compound (B') and its polymer (B) in the pressure-sensitive adhesive layer is within the above range, it is possible to achieve both good adhesion before elongation and good releasability in the low elongation range during elongation.

[0095] The polymerizable compound (B') and its polymer (B) are preferably a photopolymerizable compound and its polymer, and more preferably a polyfunctional (meth)acrylate and its polymer. When the polymerizable compound (B') is a photopolymerizable compound, the pressure-sensitive adhesive layer and the pressure-sensitive adhesive composition preferably further contain a photopolymerization initiator, which will be described later. This is because the photopolymerization of the polymerizable compound (B') can be promoted, the proportion of the polymer (B) in the pressure-sensitive adhesive layer can be increased, and the stereocontrol function for the stretched crystalline resin (A) can be effectively exerted.

[0096] In the pressure-sensitive adhesive layer, the polymerizable compound (B') and its polymer (B) exert a stereoregulatory function on the stretched crystalline resin (A), so it is preferable that the polymerizable compound (B') and its polymer (B) do not have a chemical bond with the stretched crystalline resin. That is, it is usually preferable that the polymerizable compound (B') and the polymer (B) of the polymerizable compound (B') exist in a state where they have not substantially reacted with the stretched crystalline resin.

[0097] (3) Tackifying resin The pressure-sensitive adhesive layer may further contain a tackifier resin, which allows the tape before stretching to exhibit higher adhesive strength and stably fix the adherend.

[0098] The type of tackifier resin is not particularly limited and can be appropriately selected depending on the purpose. 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. The tackifier resins 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 resins are preferred.

[0099] The softening point of the tackifier resin is not particularly limited, but is preferably 30° C. to 180° C., and more preferably 70° C. to 140° C. The softening point of the tackifier resin is measured by the softening point test method (ring and ball method) specified in either JIS K 5902 or JIS K 2207.

[0100] 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).

[0101] (4) Filler The pressure-sensitive adhesive layer may contain one or more fillers. When the pressure-sensitive adhesive layer further contains a filler, the surface of the pressure-sensitive adhesive layer becomes rough in the low elongation range during the tape stretching process, and tackiness is reduced, making it possible to prevent the tape from being reattached to an adherend after it has been peeled off.

[0102] The filler content in the pressure-sensitive adhesive layer is not particularly limited, and can be from 0 to 50% by volume, or alternatively from 5 to 50% by volume, from 10 to 50% by volume, from 15 to 45% by volume, or from 20 to 40% by volume. By setting the filler content in the pressure-sensitive adhesive layer within the above ranges, the tape before stretching can exhibit excellent adhesive strength and stably maintain fixation of the adherend, and during the tape stretching process, when the tape is stretched by pulling, the tack of the pressure-sensitive adhesive layer is greatly reduced in a low elongation range, allowing the tape to be easily peeled from the adherend and preventing re-adhesion of the adherend.

[0103] The filler content (vol %) in the pressure-sensitive adhesive layer is calculated by the method for calculating the filler content (volume ratio) in the pressure-sensitive adhesive composition (solid content), which will be described in the Examples below.

[0104] The shape of the filler may be regular or irregular, such as polygonal, cubic, elliptical, spherical, needle-like, flat, scaly, or beaded. Among these, the filler is preferably elliptical, spherical, or polygonal, more preferably spherical, because this allows the filler to maintain a state of protruding from the pressure-sensitive adhesive layer during tape stretching and improves slippage on the adherend. The filler may be of one type, or two or more types may be mixed.

[0105] The filler is preferably a solid filler having no internal voids. The filler may have a core-shell structure having a core and a shell covering the surface of the core.

[0106] The filler may be an organic filler made of a resin, an inorganic filler made of an inorganic material, or an organic-inorganic composite filler.

[0107] Examples of inorganic materials constituting the inorganic filler include metals, metal oxides, metal hydroxides, hydrated metal compounds, carbides, nitrides, titanates, carbonaceous substances, glass, minerals, etc. More specific examples of the inorganic materials include aluminum hydroxide, magnesium hydroxide, aluminum oxide, silicon oxide, magnesium oxide, zinc oxide, titanium oxide, zirconium oxide, iron oxide, silicon carbide, boron nitride, aluminum nitride, titanium nitride, silicon nitride, titanium boride, carbon, nickel, copper, aluminum, titanium, gold, silver, zirconium hydroxide, basic magnesium carbonate, dolomite, hydrotalcite, calcium hydroxide, barium hydroxide, tin oxide, tin oxide hydrate, borax, zinc borate, zinc metaborate, barium metaborate, zinc carbonate, magnesium-calcium carbonate, calcium carbonate, and barium carbonate. , molybdenum oxide, antimony oxide, red phosphorus, mica, clay, kaolin, talc, zeolite, wollastonite, smectite, silica (quartz, fumed silica, precipitated silica, silicic anhydride, fused silica, crystalline silica, ultrafine amorphous silica, etc.), potassium titanate, magnesium sulfate, sepiolite, zonolite, aluminum borate, barium sulfate, barium titanate, zirconia oxide, cerium, tin, indium, carbon, sulfur, cerium, cobalt, molybdenum, strontium, chromium, barium, lead, tin oxide, indium oxide, diamond, magnesium, platinum, zinc, manganese, stainless steel, etc. Among these, aluminum hydroxide, nickel, etc. are preferred.

[0108] The inorganic filler may be surface-treated, such as by silane coupling treatment or stearic acid treatment, in order to improve dispersibility in the pressure-sensitive adhesive layer.

[0109] The organic filler may be a resin filler made of a resin. Examples of the resin constituting the resin filler include a thermoplastic resin, a thermosetting resin, and a rubber. Among these, a thermoplastic resin is preferred. Examples of the thermoplastic resin include a thermoplastic plastic and a thermoplastic elastomer.

[0110] Specific examples of resins that constitute the resin filler include polyolefin resins such as polyethylene and polypropylene; polyether resins such as polyoxymethylene and polyoxyethylene; halogenated polyolefins such as polyvinyl chloride and polyvinylidene chloride; carbonate resins such as polycarbonate; polyester resins such as polymethylene terephthalate, polyethylene terephthalate, and polybutylene terephthalate; polystyrene resins; acrylic resins such as polyacrylonitrile; acrylate resins such as polyacrylate, polymethacrylate, polymethyl methacrylate, polyethyl acrylate, and styrene / methacrylic acid copolymer; and polyacetic acid. Examples of such resins include vinyl carboxylic acid polymers and saponified products thereof, such as vinyl acetate, ethylene-vinyl acetate copolymer, polyvinyl alcohol, and ethylene-vinyl alcohol copolymer; cellulose-based resins, such as cellulose, 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 (nylon 6, nylon 66, etc.), and aramid; epoxy resins, such as bisphenol A epoxy resin and novolac epoxy resin; polyurethane; polyimide; melamine resin; phenolic resin; benzoguanamine resin; urea-formalin resin; and fluororesin.

[0111] In particular, from the viewpoint of excellent dispersibility within the adhesive layer and adhesion to resins contained in the adhesive, such as the above-mentioned elongated crystalline resin and tackifying resin, it is preferable that the resin filler be composed of a resin selected from the group consisting of polyamide, acrylic resin, urethane resin, and cellulose, and polyamide or cellulose is more preferable.

[0112] The average particle size of the filler 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 is within the above range, the tape exhibits excellent adhesive strength before stretching and can stably maintain fixation of the adherend, while during stretching, even if the stretching distance (elongation) is small, the surface roughness of the pressure-sensitive adhesive layer increases, thereby significantly reducing tackiness.

[0113] The average particle size of the filler 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.

[0114] (5) Other ingredients The pressure-sensitive adhesive layer may contain a photopolymerization initiator. Examples of photopolymerization initiators include carbonyl compounds such as acetophenones, benzophenones, Michler's ketones, and benzoins; sulfur compounds such as tetramethylthiuram monosulfide and thioxanthones; phosphorus compounds such as acylphosphine oxides; titanium compounds such as titanocenes; and azo compounds. One type of photopolymerization initiator may be used alone, or two or more types may be used in combination. Among these, acetophenones and benzophenones are preferred.

[0115] The content of the photopolymerization initiator is preferably 0.1% by mass or more and 10% by mass or less, more preferably 0.5% by mass or more and 7% by mass or less, and even more preferably 1% by mass or more and 5% by mass or less, based on 100% by mass of the adhesive layer (solid content of the adhesive composition).

[0116] The pressure-sensitive adhesive layer preferably contains substantially no plasticizer. If the amount of plasticizer in the pressure-sensitive adhesive layer is large, contamination such as adhesive residue is likely to occur on the adherend when the tape is stretched and peeled from the adherend. The content of plasticizer in the pressure-sensitive adhesive layer is preferably 20% by mass or less, more preferably 10% by mass or less, even more preferably 5% by mass or less, and particularly preferably 0% by mass.

[0117] Examples of the plasticizer include general-purpose materials used in pressure-sensitive adhesives, such as trimellitic acid ester-based plasticizers, pyromellitic acid ester-based plasticizers, polyester-based plasticizers, adipic acid-based plasticizers, etc. More specific examples of the plasticizer include aliphatic polycarboxylic acid esters such as adipate esters, citrate esters, sebacate esters, azelaate esters, and maleate esters; aromatic polycarboxylic acid esters such as terephthalate esters, isophthalate esters, phthalate esters, trimellitic acid esters, and benzoate esters; ether-modified polyesters; epoxy-modified polyesters; and polyesters formed from polycarboxylic acids and polyols.

[0118] (6) Adhesive layer The smaller the 100% modulus of the pressure-sensitive adhesive layer, the better, specifically 4.5 MPa or less is preferred, more preferably 4 MPa or less, and even more preferably 3 MPa or less. The lower limit of the 100% modulus of the pressure-sensitive adhesive layer is not particularly limited, but is preferably 0.3 MPa or more, more preferably 0.5 MPa or more, and even more preferably 0.8 MPa or more.

[0119] The 200% modulus of the pressure-sensitive adhesive layer is preferably 0.1 MPa or more, more preferably 0.5 MPa or more, and even more preferably 1 MPa or more, and is preferably 6 MPa or less, more preferably 5 MPa or less, and even more preferably 4 MPa or less.

[0120] The 300% modulus of the pressure-sensitive adhesive layer is preferably as high as possible, more preferably greater than 1.0 MPa, more preferably 1.5 MPa or more, more preferably 2 MPa or more, and even more preferably 2.5 MPa or more. The upper limit of the 300% modulus of the pressure-sensitive adhesive layer is not particularly limited, but is preferably 10 MPa or less, more preferably 5 MPa or less, and even more preferably 7 MPa or less.

[0121] By having the 100% modulus, 200% modulus, and 300% modulus of the pressure-sensitive adhesive layer each independently fall within the above ranges, the tape can have excellent adhesive strength, and adhesive residue can be suppressed when the tape is stretched and peeled off from the adherend.

[0122] It is preferable that at least one of the 100% modulus, 200% modulus, and 300% modulus of the pressure-sensitive adhesive layer is within the above range, and it is particularly preferable that both the 100% modulus and the 300% modulus are within the above range, and it is even more preferable that the 100% modulus, 200% modulus, and 300% modulus are within the above range.

[0123] Furthermore, the greater the absolute value of the difference between the 100% modulus and the 300% modulus of the pressure-sensitive adhesive layer, the greater the change in surface adhesive strength (adhesive strength in the splitting direction) in the low elongation range before and after tape stretching, making it preferable. The absolute value of the difference between the 100% modulus and the 300% modulus of the pressure-sensitive adhesive layer is preferably 0.5 MPa or more, more preferably 0.6 MPa or more, more preferably 1.0 MPa or more, even more preferably 1.5 MPa or more, and particularly preferably 2.0 MPa or more. When the absolute value of the difference between the 100% modulus and the 300% modulus of the pressure-sensitive adhesive layer is within the above range, an excellent rate of decrease in surface adhesive strength in the low elongation range before and after tape stretching can be obtained. The upper limit of the absolute value of the difference between the 100% modulus and the 300% modulus of the pressure-sensitive adhesive layer is not particularly limited as long as it can increase the rate of decrease in surface adhesive strength before and after tape stretching, but it can be, for example, 10 MPa or less, preferably 6.0 MPa or less.

[0124] The 100% modulus, 200% modulus, and 300% modulus of the adhesive layer can be adjusted, for example, by adjusting the hard block weight ratio of the block copolymer used as the stretched crystalline resin, the blending ratio of the diblock copolymer, the blending of the tackifying resin, and the blending weight ratio of polymer (B).

[0125] The 100% modulus, 200% modulus and 300% modulus of the pressure-sensitive adhesive layer are measured by the measurement method described in <100% modulus, 200% modulus and 300% modulus> in the Examples section below.

[0126] The average thickness of the pressure-sensitive adhesive layer is not particularly limited, but 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 7 μm to 30 μm. By setting the average thickness of the pressure-sensitive adhesive layer within the above range, the tape exhibits good adhesive strength before elongation, while the adhesive strength can be reduced in a short period of time in the low elongation range during elongation.

[0127] The average thickness of the pressure-sensitive adhesive layer is measured by the measurement method described in the "Average Thickness" section in the Examples section 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 of the present disclosure 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.

[0128] 2. Base material The tape of the present disclosure may have no substrate, or may have an extensible substrate (hereinafter sometimes referred to as an extensible substrate or simply as a substrate). A tape without a substrate refers to a substrate-less tape in which both sides of a single pressure-sensitive adhesive layer serve as the adhesive surfaces of the tape.

[0129] 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 is capable of being 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 it does not need to return to its original shape when tension is released, and may have elasticity that causes it to shrink in an attempt to return to its original shape. More specifically, the term "extensible" for a substrate means that the elongation at break of the substrate is preferably within a desired range.

[0130] The elongation at break of the substrate can be, for example, 200% or more from the viewpoint of exhibiting extensibility. The elongation at break 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, the elongation at break of the substrate can be 200% or more and 1000% or less, with 250% or more and 800% or less being preferred, 300% or more and 700% or less being more preferred, and 350% or more and 600% or less being even more preferred. By having the elongation at break 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.

[0131] The breaking stress of the substrate is preferably within a range that achieves both appropriate extensibility and workability, allowing the tape to be stretched and components 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 stress 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 components to be easily peeled off.

[0132] The elongation at break and stress at break of the substrate can be adjusted by appropriately selecting the material of the substrate or by performing a stretching treatment during the manufacturing process of the substrate.

[0133] The elongation at break and stress at break of the substrate are measured by the measurement methods described in <Elongation at break, stress at break> in the Examples section below.

[0134] 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.

[0135] The 200% modulus of the substrate is preferably 3 MPa or more and 35 MPa or less, more preferably 4 MPa or more and 25 MPa or less, even more preferably 5 MPa or more and 20 MPa or less, and particularly preferably 6 MPa or more and 15 MPa or less.

[0136] 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.

[0137] By having the 100% modulus, 200% modulus, and 300% modulus of the substrate each independently fall within the above range, the tape 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 tape peeling operation even when the adherend is a minute component of millimeter or micron size. Furthermore, when stretching the tape of the present disclosure, it is easily peeled from the adherend at a relatively low elongation. If the modulus of the substrate is too low, regions other than the adhesive region between the tape and the adherend (non-adhesive regions) will elongate preferentially, making peeling between the tape and the adherend less likely to occur.

[0138] The substrate preferably has at least one of the 100% modulus, 200% modulus, and 300% modulus within the above range, and more preferably has both the 100% modulus and 300% modulus within the above range, and more preferably has all of the 100% modulus, 200% modulus, and 300% modulus within the above range.

[0139] Furthermore, the absolute value of the difference between the 100% modulus and the 300% modulus of the substrate is preferably 1 MPa or more and 100 MPa or less, more preferably 3 MPa or more and 80 MPa or less, even more preferably 7 MPa or more and 60 MPa or less, even more preferably 10 MPa or more and 50 MPa or less, and particularly preferably 12 MPa or more and 40 MPa or less. When the absolute value of the difference between the 100% modulus and the 300% modulus of the substrate is within the above range, the force required to stretch the tape of the present disclosure to peel off the adherend can be reduced, and the distance the tape of the present disclosure needs to be stretched to peel off the adherend can be reduced, thereby saving work space.

[0140] The 100% modulus, 200% modulus and 300% modulus of the substrate can be adjusted, for example, by the composition of the substrate, the type of resin constituting the substrate, the thickness of the substrate, uniaxial or biaxial stretching treatment and the like.

[0141] The 100% modulus, 200% modulus, and 300% modulus of the substrate are measured by the measurement method described in <100% modulus, 200% modulus, and 300% modulus> in the Examples section below.

[0142] The hardness of the substrate is not particularly limited as long as it does not impair the functions of the tape of the present disclosure (particularly the functions of the pressure-sensitive adhesive layer), 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, thereby 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.

[0143] The hardness of the substrate is Shore hardness, and is a value of Type A hardness or Type D hardness measured by the method described in "Rubber Hardness" in the Examples section below, using a durometer (spring type rubber durometer, model GS-719G, manufactured by Teclock Corporation) or a durometer (spring type rubber durometer, model GS-720G, manufactured by Teclock Corporation) in accordance with JIS K 6253. More specifically, Shore hardness A (Type A) is a value measured using a durometer (spring type rubber durometer, model GS-719G, manufactured by Teclock Corporation) in accordance with JIS K 6253, and Shore hardness D (Type D) is a value measured using a durometer (spring type rubber durometer, model GS-720G, manufactured by Teclock Corporation) in accordance with JIS K 6253.

[0144] The thickness of the substrate is not particularly limited as long as it can exhibit the desired physical properties described above, but can be, for example, 5 μm to 500 μm, preferably 10 μm to 250 μm, more preferably 25 μm to 200 μm, and even more preferably 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 can be obtained and it can be easily stretched with a small force, improving the releasability of the parts fixed to the tape.

[0145] The thickness of the substrate is measured by the measurement method described in the Examples section below.

[0146] The substrate may be a single layer or may have a multilayer structure consisting of two or more layers, so long as it is capable of providing the desired physical properties.

[0147] The substrate may be, for example, a resin film containing a resin as a main component. 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, nylon, etc. These resins may be used alone or in combination of two or more.

[0148] In particular, the substrate preferably contains, as a main component, a resin selected from the group consisting of styrene-based resins, urethane-based resins, and acrylic-based resins. That is, the substrate is preferably selected from the group consisting of styrene-based resin films, urethane-based resin films, and acrylic-based resin films. The main component refers to the component that is contained in the largest amount in the total amount of the substrate, and specifically, the component that is contained in the largest amount in the total amount of the substrate is preferably 50% by mass or 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.

[0149] (styrene resin) The styrene-based resin has a structural unit derived from an aromatic vinyl compound. Specific examples of the structural unit derived from an aromatic vinyl compound can be selected from the structural units derived from aromatic vinyl compounds exemplified in the above section "1. Pressure-sensitive adhesive layer." Of these, it is preferable for the resin to contain a structural unit derived from styrene represented by the following chemical formula (III):

[0150] [ka]

[0151] The styrene-based resin may have one or more functional groups in the molecular chain and / or at the molecular terminal, or may have no functional groups. Examples of the functional groups include alkyl groups, carboxyl groups, hydroxyl groups, acid anhydride groups, amino groups, and epoxy groups. In addition, hydrogen atoms on the benzene ring of the styrene-based resin may be substituted with alkyl groups such as methyl and ethyl, and the number of alkyl groups to be substituted may be any number from 1 to 5.

[0152] 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, even 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. By setting the proportion of the styrene-derived structural units within the above range, the elongation at break and stress at break of the substrate can be easily obtained within suitable ranges.

[0153] Among the above styrene-based resins, styrene-based block copolymers are preferred because they can reduce the elastic modulus of the substrate in a 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 styrene-based block copolymer, or may be a mixture of two or more types of styrene-based block copolymers.

[0154] The styrene-based block copolymer has a structural unit derived from an aromatic vinyl compound and a structural unit derived from a conjugated diene compound. The aromatic vinyl compound constituting the structural unit derived from the aromatic vinyl compound and the conjugated diene compound constituting the structure derived from the conjugated diene compound include, for example, the aromatic vinyl compounds and conjugated diene compounds described in the above section "1. Pressure-sensitive adhesive layer". Further, for example, the aromatic vinyl compounds and conjugated diene compounds disclosed in JP 2022-094735 A can be mentioned.

[0155] The styrene-based block copolymer may be a diblock copolymer, a triblock copolymer, or a tetrablock or higher copolymer. The styrene-based block copolymer may also be a mixture of a diblock copolymer and a triblock copolymer. Among these, it is more preferable that the styrene-based resin contains at least a styrene-based triblock copolymer, from the viewpoint of achieving both excellent cohesion and extensibility of the substrate. The styrene-based triblock copolymer preferably has structural units derived from an aromatic vinyl compound in the hard segment and structural units derived from a conjugated diene compound in the soft segment. Furthermore, it is preferable that the structural units derived from the aromatic vinyl compound are in the end block phase, and the structural units derived from the conjugated diene compound are in the mid block phase.

[0156] Specific examples of styrene-based block copolymers include styrene-isoprene block copolymers, styrene-isoprene-styrene block copolymers, styrene-isoprene-butadiene-styrene block copolymers, styrene-butadiene-styrene block copolymers, styrene-ethylene-butylene block copolymers, and styrene-ethylene-propylene block copolymers. These may be used alone or in combination of two or more. Examples of the above mixtures include a mixture of a styrene-isoprene block copolymer and a styrene-isoprene-styrene block copolymer.

[0157] The styrene-based block copolymer may also 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 improved breaking strength (stress at break) of the tape.

[0158] 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.

[0159] 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 can further reduce the elastic modulus of the substrate in the low elongation range during the tape stretching process, resulting in a substrate with high strength and excellent elongation at break.

[0160] 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.

[0161] (urethane resin) The urethane resin has a structural unit derived from a polyol and a structural unit derived from a polyisocyanate, and examples of the urethane resin include ester polyurethane, ether polyurethane, and polycarbonate polyurethane.

[0162] 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.

[0163] 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.

[0164] 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.

[0165] 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.

[0166] 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.

[0167] 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.

[0168] 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.

[0169] The polyurethane 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.

[0170] (acrylic polymer) The acrylic polymer may be a random polymer or a block polymer, but preferably contains an acrylic block polymer because it is easy to adjust 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 a good balance between breaking strength (stress at break) and extensibility due to its excellent cohesive force. The acrylic polymer may contain two or more acrylic block copolymers with different block structures.

[0171] 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.

[0172] 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.

[0173] 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.

[0174] 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.

[0175] 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.

[0176] 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.

[0177] 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.

[0178] 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.

[0179] 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 a good balance between excellent extensibility and breaking strength (stress at break) and also have good thickness uniformity. If the Mw and Mn of the acrylic block copolymer are too small, the substrate will not have the desired extensibility or breaking strength (stress at break). On the other hand, if the Mw and Mn are too large, the acrylic block copolymer will be 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.

[0180] Among these, it is preferable that the Mw of the block copolymer is 100,000 or more and 250,000 or less, and the Mn is 100,000 or more and 250,000 or less, and it is even more preferable that the Mw is 130,000 or more and 230,000 or less, and the Mn is 130,000 or more and 230,000 or less.

[0181] 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.

[0182] 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.

[0183] (others) When the resin constituting the substrate 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 (stress at break). In particular, it is preferable that the block copolymer be a triblock or larger copolymer, and that the soft segment have 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 segments (endblocks) and the soft segments (midblocks) can achieve a good balance between excellent cohesive strength (stress at break) and extensibility. Examples of such resins include hydrogenated styrene triblock copolymers, and specific compounds are the same as those described above and in the section "1. Pressure-sensitive adhesive layer" above for the styrene block polymer (A1).

[0184] (Other ingredients) The substrate may contain other components as needed. Examples of other components include tackifier resins, 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, silica beads, organic beads, and inorganic fillers. The content of other components in the substrate can be appropriately selected within a range that does not impair the properties of the substrate.

[0185] 3. Any configuration In the tape of the present disclosure, the pressure-sensitive adhesive layer may be in contact with the surface of the substrate, or an intermediate layer may be provided between the pressure-sensitive adhesive layer and the substrate. The intermediate layer can further enhance the adhesion between the pressure-sensitive adhesive layer and the substrate. The intermediate layer is not particularly limited as long as it is a layer that can enhance the adhesion between the pressure-sensitive adhesive layer and the substrate, and examples thereof include an intermediate pressure-sensitive adhesive layer different from the pressure-sensitive adhesive layer, a primer layer, etc.

[0186] The intermediate layer is primarily composed of a polymer such as an acrylic polymer, a urethane polymer, an epoxy polymer, a polyester polymer, a polyvinyl polymer (e.g., polyvinyl alcohol, vinyl chloride-vinyl acetate copolymer, ethylene-vinyl acetate copolymer, urethane-vinyl acetate copolymer, etc.), a rubber polymer (e.g., a styrene block copolymer, etc.), or a thermoplastic elastomer. These may be used alone or in combination. The polymer content in the intermediate layer can be, for example, 30% by mass or more, preferably 40% by mass or more, more preferably 50% by mass or more, even more preferably 60% by mass or more, and particularly preferably 80% by mass, based on 100% by mass of the total amount of the intermediate layer.

[0187] When the intermediate layer is an intermediate pressure-sensitive adhesive layer, the pressure-sensitive adhesive constituting the intermediate pressure-sensitive adhesive layer can be, for example, a pressure-sensitive adhesive containing the above-mentioned polymer as a main component, and specific examples include acrylic pressure-sensitive adhesives, urethane pressure-sensitive adhesives, rubber pressure-sensitive adhesives, polyester pressure-sensitive adhesives, etc. These may be used alone or in combination. Furthermore, when the intermediate layer is a primer layer, the primer agent constituting the primer layer can be, for example, a primer agent containing the above-mentioned polymer as a main component.

[0188] In addition to the above-mentioned polymer, the intermediate layer may contain additives such as a tackifying resin, an antifoaming agent, a coatability improver, a thickener, an organic lubricant, an ultraviolet absorber, an antioxidant, a foaming agent, a dye, a pigment, and particles, as necessary.

[0189] The thickness of the intermediate layer is not particularly limited, but from the viewpoints of improving the adhesion between the pressure-sensitive adhesive layer and the substrate and making it easier for distortion in the pressure-sensitive adhesive layer to occur when the tape is stretched and peeled off, it is preferably in the range of 0.01 μm to 100 μm, more preferably in the range of 0.1 μm to 50 μm, and more preferably in the range of 0.5 μm to 10 μm.

[0190] The tape of the present disclosure may have a release liner on the surface of the adhesive layer opposite the substrate. Known release liners can be used, such as paper, plastic film, polytetrafluoroethylene (PTFE) film, or plastic film with a release treatment such as silicone treatment or fluorinated silicone treatment applied to the surface. The release liner is usually peeled off and removed when the adherend is adhered to the tape of the present disclosure. When the tape of the present disclosure is a double-sided tape having adhesive surfaces on both sides, the release liner may be provided on one adhesive surface of the tape of the present disclosure, or on both adhesive surfaces.

[0191] 4. Temporary fixing tape The total thickness of the tape of the present disclosure is not particularly limited as long as it can exhibit the desired functions, but is preferably from 10 μm to 1500 μm, more preferably from 30 μm to 1000 μm, and even more preferably from 50 μm to 500 μm. Note that the thickness of the release liner is not included in the total thickness of the tape.

[0192] The elongation at break 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 500%. By setting the elongation at break 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.

[0193] The breaking stress 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 stress 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.

[0194] The elongation at break and stress at break of the tape of the present disclosure can be adjusted, for example, by the elongation at break and stress at break of each layer constituting the tape of the present disclosure, and in particular, when the tape of the present disclosure has a substrate, by the elongation at break and stress at break of the substrate.

[0195] The elongation at break and stress at break of the tape are measured by the measurement method described in <Elongation at break and stress at break> in the Examples section below.

[0196] The 100% modulus of the tape of the present disclosure is preferably small from the viewpoint of reducing the stretching force in the initial stage of elongation, and 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.

[0197] The 200% modulus of the tape of the present disclosure is preferably 0.5 MPa or more and 40 MPa or less, more preferably 1.0 MPa or more and 30 MPa or less, even more preferably 1.5 MPa or more and 25 MPa or less, and particularly preferably 2.0 MPa or more and 20 MPa or less.

[0198] 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.

[0199] When the 100% modulus, 200% modulus, and 300% modulus of the tape of the present disclosure are each independently within the above ranges, the tape can be stretched with a small force in the initial stage of elongation of the tape of the present disclosure, and the stress required for the tape to be stretched and peeled from the adherend can be reduced.

[0200] The tape of the present disclosure preferably has at least one of the 100% modulus, 200% modulus, and 300% modulus within the above range, and more preferably has both the 100% modulus and the 300% modulus within the above range, and more preferably has all of the 100% modulus, 200% modulus, and 300% modulus within the above range.

[0201] Furthermore, the absolute value of the difference between the 100% modulus and the 300% modulus of the tape of the present disclosure is preferably 1 MPa or more and 100 MPa or less, more preferably 3 MPa or more and 80 MPa or less, even more preferably 7 MPa or more and 60 MPa or less, even more preferably 10 MPa or more and 50 MPa or less, and particularly preferably 12 MPa or more and 40 MPa or less. When the absolute value of the difference between the 100% modulus and the 300% modulus of the tape of the present disclosure is within the above range, the force required to stretch the tape of the present disclosure to peel off the adherend can be reduced, and the distance the tape of the present disclosure needs to be stretched to peel off the adherend can be reduced, thereby saving work space.

[0202] The 100% modulus, 200% modulus, and 300% modulus of the tape of the present disclosure can be adjusted, for example, by the modulus of each layer constituting the tape, particularly the modulus of the substrate.

[0203] The 100% modulus, 200% modulus, and 300% modulus of the tape of the present disclosure are measured by the measurement method described in <100% modulus, 200% modulus, and 300% modulus> in the Examples section below.

[0204] The 180° peel adhesive strength of the tape of the present disclosure is not particularly limited as long as it is strong enough to fix and hold an adherend, particularly a small component such as an MLCC, but is, for example, preferably 0.1 N / 20 mm to 12 N / 20 mm, more preferably 0.3 N / 20 mm to 8 N / 20 mm, and even more preferably 0.5 N / 20 mm to 6 N / 20 mm. By keeping the 180° peel adhesive strength of the tape of the present disclosure within the above range, it is possible to sufficiently fix an adherend, and when stretched to peel from the adherend, an increase in peel strength is suppressed, allowing for peeling in a low elongation range and providing good removability.

[0205] The 180° peel adhesive strength of the tape of the present disclosure is measured by the measurement method described in <180° Peel Adhesion Strength> in the Examples section below. When the tape of the present disclosure is a double-sided tape having pressure-sensitive adhesive layers on both sides of a substrate, the 180° peel adhesive strength is measured by lining the adhesive surface opposite the adhesive surface for which the strength is to be measured with a 25 μm-thick PET film.

[0206] The surface adhesive strength (initial surface adhesive strength, also called initial splitting adhesive strength) P0 of the tape of the present disclosure before stretching is not particularly limited as long as it is strong enough to fix and hold an adherend (especially a small component such as an MLCC), but the higher the strength, the better from the viewpoint of preventing the adherend from falling off the tape before stretching. The surface adhesive strength P0 of the tape of the present disclosure before stretching is 0.3 N / cm 2 More than 1.0N / cm is preferable. 2 More preferably, 2.0 N / cm 2 The upper limit of the surface adhesive strength of the tape of the present disclosure before stretching is not particularly limited as long as it can temporarily fix the adherend, but is preferably 25 N / cm 2 Less than 22N / cm is preferable. 2 Less than 20N / cm is more preferable. 2 The following is even more preferred:

[0207] When the surface adhesive strength P0 of the tape of the present disclosure before elongation is within the above range, the tape surface can sufficiently hold the adherend, and high temporary fixation properties can be achieved. The surface adhesive strength P0 of the tape of the present disclosure before elongation can be adjusted by selecting, for example, the combination of compositions of the pressure-sensitive adhesive layer.

[0208] The surface adhesive strength of the tape of the present disclosure at 200% elongation (surface adhesive strength at 200% elongation, also referred to as split adhesive strength at 200% elongation) P 200 Even if the tape is not stretched to the high elongation range, the adhesive force in the splitting direction (i.e., surface adhesive force, also called split adhesive force) is sufficiently small in the low elongation range, and peeling can be easily confirmed for particularly small adherends, so the adhesive force is set to 0.0001 N / cm 2 More than 20N / cm 2 Below, 0.001N / cm 2 More than 10N / cm 2 Below, 0.01N / cm 2 More than 5N / cm 2 Below, 0.01N / cm 2 More than 1N / cm 2 It is preferable that:

[0209] Surface adhesive strength of the tape of the present disclosure at 300% elongation (surface adhesive strength at 300% elongation, also referred to as split adhesive strength at 300% elongation) P 300 The smaller the better. Specifically, P 300 is 10N / cm 2 Preferably, it is less than 5N / cm 2 Less than 3N / cm is more preferable. 2 More preferably, 1.5 N / cm 2 Less than 1N / 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 in the above range, the adherend can be easily peeled from the stretched tape, and the tape can be prevented from being re-attached to the adherend. 300 The lower limit is 0 N / cm 2 (i.e., adhesive strength is lost) is most preferable, but it is acceptable as long as it does not hinder peeling of the adherend after elongation, for example, 0 N / cm 2 may be greater than 0.01 N / cm 2 may be 0.1 N / cm or more, 2 It may be more than that.

[0210] 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 rate of decrease in the surface adhesive strength (hereinafter referred to as the surface adhesive strength decrease rate) is preferably 50% or more, more preferably 60% or more, and even more preferably 70% or more. When the surface adhesive strength decrease rate is within the above range, the surface adhesive strength tends to decrease until the tape is stretched 300%, which is preferable because it provides a better balance between fixation before stretching and releasability after stretching. The surface adhesive strength P when stretched 300% relative to the surface adhesive strength P0 before stretching is 300 The rate of decrease is calculated by the following formula. Surface adhesion reduction rate (%)=[(P0-P 300 ) / P0]×100%...expression

[0211] Above surface adhesion P0, P 200 , P 300 are the surface adhesive strength before elongation (P0) and the surface adhesive strength after 200% elongation (P 200 )>, <300% elongation surface adhesive strength (P 300 )>.

[0212] The tape of the present disclosure has an elongation (2012M peel elongation) E when peeled from an adherend having a surface area of ​​2.0 mm length x 1.2 mm width (2012M size) 2012 is preferably less than 350%, more preferably 300% or less, more preferably 230% or less, even more preferably 200% or less, even more preferably 180% or less, and particularly preferably 150% or less. 2012 The lower limit of the elongation at peeling E of the tape of the present disclosure is not particularly limited, but is preferably more than 1%, more preferably 5% or more, more preferably 15% or more, more preferably 30% or more, and even more preferably 70% or more. 2012 By setting the above range, peeling is possible in a low elongation range even from adherends whose surface area in contact with the tape is on the order of millimeters square meters or less, and especially on the order of micrometers square meters.

[0213] The above elongation E 2012is measured by the measurement method described in <Stretch Peelability (2012M Peel Elongation)> in the Examples section below.

[0214] The tape of the present disclosure has a surface area of ​​0.6 mm length x 0.3 mm width square (0603M size) when peeled from an adherend (multilayer ceramic capacitor, Murata Manufacturing Co., Ltd., product number GRM033B31C104KE84D, size 0603) with a peel elongation (elongation at peeling) E 0603 is preferably 500% or less, more preferably 400% or less, and even more preferably 300% or less. 0603 The lower limit of the elongation at peeling E of the tape of the present disclosure is sufficient as long as it is more than 1%, and is preferably 10% or more, more preferably 30% or more, and particularly preferably 50% or more. 0603 By setting the value within the above range, peeling is possible in a low elongation range even for adherends with minute surface areas on the order of millimeter square meters or micrometer square meters.

[0215] The above elongation E 0603 is the elongation of the tape (elongation at peeling) E when all 10 adherends are peeled off from the tape under their own weight, or when the tape is vibrated by lightly flicking it with a finger and all 10 adherends fall off, according to the measurement method described in <Elongation Peel Property (0603M Elongation at Peeling)> in the Examples section below. 0603 Let's say.

[0216] The tape of the present disclosure can be manufactured using a known manufacturing method. Examples of manufacturing methods for the tape of the present disclosure include a method of applying a pressure-sensitive adhesive composition containing at least an elongated crystalline resin and a polymerizable compound to one side of a substrate, as described above in the section "1. Pressure-sensitive adhesive layer," and applying an external stimulus such as light or heat to the coating film to polymerize the polymerizable compound to form a pressure-sensitive adhesive layer; a method of applying the pressure-sensitive adhesive composition to a release liner, applying an external stimulus such as light or heat to the coating film to polymerize the polymerizable compound to form a pressure-sensitive adhesive layer, and transferring the pressure-sensitive adhesive layer to a substrate to form a pressure-sensitive adhesive layer on the substrate. The method for applying the pressure-sensitive adhesive composition is not particularly limited, and known methods such as a roll coater or die coater can be used.

[0217] Furthermore, when the tape of the present disclosure has an intermediate layer between the substrate and the pressure-sensitive adhesive layer, a method for manufacturing the tape of the present disclosure can be used, for example, by forming an intermediate layer on a release liner using a composition for forming an intermediate layer, laminating the intermediate layer to the surface of the substrate to form a laminated intermediate body, and then peeling off the release liner from the surface of the intermediate layer and laminating an adhesive layer formed on another release liner.

[0218] The tape of the present disclosure can be suitably used in applications requiring temporary fixation, such as fixing and re-detaching an adherend. In particular, it can be suitably used in process applications such as manufacturing processes for ceramic parts and semiconductor devices. That is, the tape of the present disclosure can be suitably used as a temporary fixing tape or a process tape.

[0219] Furthermore, the tape of the present disclosure is not limited to applications such as temporary fixing of parts or process applications in part manufacturing processes, and can also be used for joining two or more parts, for example, depending on the magnitude of the initial adhesive strength before stretching.

[0220] II. Parts manufacturing method The method for manufacturing a component according to the present disclosure is a method for manufacturing a component using the temporary fixing tape described above in the section "I. Temporary Fixing Tape," and includes a peeling step of stretching the temporary fixing tape, to which one or more components are fixed, in at least one direction to peel the components from the temporary fixing tape.

[0221] 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.

[0222] According to the component manufacturing method of the present disclosure, a processed product can be easily and simply peeled from the tape by stretching the tape, without the need for applying energy such as heat or active energy rays. In particular, the component manufacturing method of the present disclosure uses the temporary fixing tape described above in the section "I. Temporary Fixing Tape." Therefore, before the tape is stretched, the component is sufficiently fixed and held by the tape. Meanwhile, during the process of stretching the tape, the surface adhesive strength of the tape is significantly reduced in the low elongation range. This allows multiple components temporarily fixed to the tape to be peeled off at once without excessively stretching the tape, allowing for easy mass production of components. The effects of the component manufacturing method of the present disclosure are particularly pronounced when the components are minute components of millimeter or micron size.

[0223] In the manufacturing method of the present disclosure, the component fixed to the tape may be a component before processing or a component after processing. Also, in the manufacturing method of the present disclosure, the component fixed to the tape may be processed on the tape, so that the component may be a component after processing when peeled off. A part before processing may be called a workpiece, and a part after processing may be called a processed product, and processed products and workpieces may be collectively referred to as "parts."

[0224] 1. Peeling process The peeling step is a step of stretching a temporary fixing tape having one or more components fixed onto its pressure-sensitive adhesive layer in at least one direction to peel the components from the temporary fixing tape. The temporary fixing tape having one or more components fixed thereto is the temporary fixing tape of the present disclosure described above in the section "I. Temporary Fixing Tape."

[0225] The direction in which the tape is stretched can be set arbitrarily when viewed from above. The direction in which the temporary fixing tape is stretched needs only to be at least one direction, and may be one direction, two intersecting directions, three or more multiaxial directions, or omnidirectional (360°). The specific direction in which the tape of the present disclosure is stretched is not particularly limited, but for example, when the tape has a long shape, the stretching direction can be appropriately selected from the longitudinal direction of the tape, the lateral direction of the tape, a direction oblique to the longitudinal direction of the tape, and a combination of these directions. Furthermore, the stretching direction of the tape of the present disclosure may be a radial direction centered on any one point (reference point) on the tape.

[0226] When the tape is stretched in two or more directions, it may be stretched simultaneously in two or more directions (simultaneous stretching), or sequentially in each direction (sequential stretching). When the tape is stretched in two directions, it is preferable that the first and second directions are generally perpendicular to each other. The term "generally perpendicular" does not necessarily mean that the second direction is exactly 90° relative to the first direction, as long as it is approximately 90°. However, for example, an angle of 85° to 95°, or even an angle of 88° to 92°, is acceptable.

[0227] In addition, when one of the tape stretching directions (stretching directions) is 180° opposite to the other stretching direction, the two stretching directions are considered to be bidirectional and the same direction. 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)).

[0228] The means for stretching the tape (stretching member) 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 tape, the stretched state may be maintained by a grip ring or the like.

[0229] The method for stretching the tape is not particularly limited, but examples include a method in which the peripheral edge of the tape is clamped with a stretching member (e.g., a tensioning tool) and pulled in a certain direction, a method in which the tape is pulled using the peripheral speed of two stretching members (e.g., rolls), and a method in which two opposing stretching members (e.g., rolls) rotate in opposite directions (e.g., one roll rotates clockwise and the other opposing roll rotates counterclockwise). Another method for stretching the tape involves, for example, pressing a stretching member (e.g., a stage, pin, etc.) against the tape from the side opposite the component placement side, pushing (protruding) the tape toward the component placement side, and then pulling the tape. Pulling the tape in this manner allows the tape to be stretched in all directions, allowing multiple components to be peeled off from the tape at once.

[0230] The parts peeled off by stretching the temporary fixing tape in the peeling step can be detached (removed) from the tape by a desired method. Methods for detaching (removing) a processed product from the stretched temporary fixing tape include, for example, a method of detaching (removing) from the tape by dropping it under its own weight, a method of detaching (removing) from the tape by applying vibration, and a method of detaching (removing) from the tape by means of suction, adsorption, clamping, sweeping, etc. Examples of suction means include a vacuum and a cleaning device. Examples of adsorption means include a suction cup, a suction machine, a suction collet, etc. Examples of clamping means include tweezers and a clamp. Examples of sweeping means include a swinging plate, wind pressure, a brush, etc. Among these, the use of the gravity dropping method, the vibration applying method, sweeping means, and suction means is preferred.

[0231] 2.Optional process The method for manufacturing a component according to the present disclosure includes at least the peeling step described above, but may also include other steps as necessary.

[0232] (1) Transfer process The method for manufacturing a component according to the present disclosure may include a transfer step of placing another adherend on the surface of the component opposite to the surface to be bonded to the temporary fixing tape, and stretching the temporary fixing tape to transfer the component to the other adherend. The transfer step is carried out simultaneously with the peeling step, and therefore can be included in the peeling step.

[0233] 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.

[0234] The other adherend onto which the part is transferred is not particularly limited as long as it can directly or indirectly fix the transferred part, and examples thereof include adhesive tape, pressure-sensitive adhesive tape, other parts coated with adhesive, etc.

[0235] (2) Processing process The method for manufacturing a part according to the present disclosure may include a processing step in which a pre-processed part (workpiece) fixed on the adhesive layer of the tape described above in the section "I. Temporary Fixing Tape" is processed to obtain one or more processed parts (processed products). The processing step is usually carried out before the peeling step, but the peeling step may also be carried out during the processing step.

[0236] The above-mentioned pre-processed part (workpiece) is not particularly limited and can be appropriately selected depending on the type of post-processed part (workpiece). Examples of pre-processed parts (workpieces) include ceramic green sheet laminates, semiconductor wafers, optical device wafers, and various plate materials such as glass and quartz crystal.

[0237] In the above processing step, the processing performed on the pre-processed part (workpiece) is not particularly limited, and examples thereof include cutting, cutting (dicing), polishing, etching, etc. Examples of the pre-processed part include a green sheet used for forming an MLCC.

[0238] (3) Other processes In addition to the steps described above, the method for manufacturing a component according to the present disclosure may include other steps, such as a cleaning step, a curing step, etc. Furthermore, the component peeled off from the temporary fixing tape in the peeling step may be sent to other steps such as further processing, component assembly, or joining with other components.

[0239] 3. Parts In the peeling step of the component manufacturing method of the present disclosure, the size of each component peeled from the tape is not particularly limited, but millimeter-level size is preferable, and micro-level size is more preferable. Specifically, the component preferably has a size that includes the dimensional size specified in JIS C 5101-22:2014 (IEC 60384-22:2011).

[0240] The surface area of ​​the surface that comes into contact with the tape per component that is peeled off in the peeling step 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, 0.001 mm 2 More than 0.01mm, preferably 2 It can be more than that.

[0241] 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 electronic components such as inductors.

[0242] 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]

[0243] The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples.

[0244] 1. Evaluation and measurement methods Each physical property was measured by the following method. When the measurement object was a pressure-sensitive adhesive layer, each parameter related to the pressure-sensitive adhesive layer was measured by applying the pressure-sensitive adhesive composition onto a release liner with an applicator so that the thickness after drying would be 30 μm, drying at 80° C. for 3 minutes to form a pressure-sensitive adhesive layer, cutting into a No. 3 dumbbell shape, and removing the release liner.

[0245] <100% modulus, 200% modulus, 300% modulus> The measurement object (adhesive layer, substrate, tape, etc.) was cut into a JIS K6251 No. 3 dumbbell shape (gauge length 20 mm, gauge length width 5 mm), and pulled in the longitudinal direction at a tensile speed of 500 mm / min using a Tensilon tensile testing machine (model: RTF-1210, manufactured by A&D Co., Ltd.) under measurement atmosphere conditions of 23°C and 50% RH. The stress value when the gauge length after elongation became twice the gauge length distance before elongation (initial gauge length distance) (when the elongation calculated by the following formula (1) was 100%) was defined as the 100% modulus of the measurement object. In addition, a sample was stretched in the same manner as in the above-mentioned method for measuring the 100% modulus, and the stress value when the gauge length after stretching was three times the gauge length before stretching (initial gauge length) (when the elongation calculated by the following formula (1) was 200%) was defined as the 200% modulus of the measured object, and the stress value when the gauge length after stretching was four times the gauge length before stretching (initial gauge length) (when the elongation calculated by the following formula (1) was 300%) was defined as the 300% modulus of the measured object. Modulus elongation (%) = {(gauge length after elongation) - (gauge length before elongation)} / (gauge length before elongation) Formula (1)

[0246] Additionally, the ratio of the 300% modulus to the 100% modulus (300% modulus / 100% modulus) and the absolute value of the difference between the 100% modulus and the 300% modulus (|Δ(100% modulus−300% modulus)|) were calculated.

[0247] <Elongation at break, stress at break> The test specimen was cut into a JIS K6251 No. 3 dumbbell shape (gauge length 20 mm, gauge 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 at which the sample broke was taken as the breaking stress of the test specimen, and the tensile elongation at break was taken as the breaking elongation.

[0248] <Average thickness> The thickness of each of the five points at 10 mm intervals across the width of the object to be measured (adhesive layer, substrate, tape, etc.) 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 calculated.

[0249] <Rubber hardness> The rubber hardness (Shore hardness) was measured using a durometer (spring type rubber hardness tester, model: GS-719G, manufactured by Teclock Corporation) and a durometer (spring type rubber hardness tester, model: GS-720G, manufactured by Teclock Corporation) in accordance with JIS K 6253. The Shore hardness of the above base polymer was measured after a test piece sheet was prepared from the base polymer and 15 seconds or more had elapsed since the load was applied.

[0250] <Average particle size of filler> The average particle size (primary particle size) of the filler was measured using a measuring device (Microtrac) that uses a laser diffraction scattering method.

[0251] <180° peel adhesive strength> In accordance with JIS Z 0237, the tape was cut into a length of 150 mm and a width of 20 mm. The adhesive surface of the tape was attached to a stainless steel plate (200 mm long, 30 mm wide, and 3 mm thick) at 23°C and 50% RH. The tape was pressed back and forth with a roller under a 2 kg load, and then allowed to stand for 1 hour at 23°C and 50% RH. The 180° peel adhesive strength was measured by peeling the tape from the stainless steel plate in an 180° direction at a rate of 300 mm / min using a Tensilon tensile tester (model RTF-1210, manufactured by A&D Co., Ltd.) at 23°C and 50% RH.

[0252] <Stretch peelability (2012M peel elongation)> The tape was cut to a length of 200 mm and a width of 10 mm, and both ends, each measuring 50 mm and 10 mm, were laminated with a 50 μm-thick PET film to form gripping tabs for longitudinal stretching of the tape. Ten multilayer ceramic capacitors (Samsung Electro-Mechanics, part number CL21B103KCANNNC, size 2012 (metric)) were prepared and attached to the center of the adhesive layer of the tape in two rows of five, with the length of the tape aligned with the length of the multilayer ceramic capacitors. The test specimens were then compressed for 10 seconds with a load of 1 kg per 10 pieces. While holding the test specimen horizontally with the multilayer ceramic capacitors facing downward, the tab at one end of the tape was placed in a fixture. The tab on the other end of the tape was then gripped and stretched horizontally at a rate of 500 mm / min. The elongation of the tape (elongation at peeling) when all 10 multilayer ceramic capacitors had dropped from the tape was measured as the elongation E. 2012 The elongation of the tape (elongation at peeling) was calculated using the following formula (2). The gauge length is the length of the tape excluding the tab regions on both sides, and the gauge length before elongation (initial gauge length) was 100 mm (= tape length 200 mm - tab region length 50 mm × 2). Elongation (%) = {(gauge length after elongation) - (gauge length before elongation)} / (gauge length before elongation) × 100 Formula (2)

[0253] <Chip cutting ability> 100 parts by weight of barium titanate (particle diameter 150 nm), 16 parts by weight of toluene, and 16 parts by weight of ethanol were mixed and stirred in a ball mill, followed by 93.75 parts by weight of polyvinyl acetal resin solution (Sekisui Chemical Co., Ltd., BH-3 diluted with a 4:6 ethanol:toluene solution to a solids content of 10%) and 2.63 parts by weight of bis(2-ethylhexyl) phthalate (J-Plus Corporation, DOP) to create a slurry. This slurry was applied to the release side of a release-treated PET film to a dry thickness of 20 μm and dried at 85°C for 3 minutes to create a ceramic sheet (1). The release-treated PET film was removed from the ceramic sheet (1), and 18 sheets were stacked. The entire assembly was pressed together and trimmed to a 50 mm x 50 mm size to create a ceramic block (1).

[0254] The tape was cut into a length of 130 mm and a width of 130 mm. 10 mm square grid marks had been previously marked on the tape, and the ceramic block (1) was attached to the center of each mark. The tape was placed on the stage of a cutting machine (MTC-ST manufactured by Micro-Tec Corporation), and 8,450 ceramic chips measuring 0.7 mm x 0.35 mm were cut from a 45 mm x 45 mm area from the center of the ceramic block (1) under conditions of a blade speed of 200 mm / min, a work temperature of 70°C, a blade temperature of 40°C, and a stripper pressure of 0.15 MPa. The chip cutting ability was evaluated using the following criteria: (Rating) ⊚: Ceramic chips could be cut without peeling from the tape; ◯: Ceramic chips could be cut with 1 or more but less than 100 chips peeled from the tape; ×: 100 or more ceramic chips peeled from the tape.

[0255] <Chip peelability (elongation when ceramic chip is peeled off)> The tape with ceramic chips mounted thereon, prepared in the above evaluation of "Chip Breakability," was used as a test specimen to evaluate peelability using a tape stretching device for the test specimen. Specifically, the outer peripheral region of the test specimen, where only the tape was present and no ceramic chips were attached (the peripheral region of the region on the tape surface where the ceramic chips were attached), was placed on a fixed ring with an inner cavity of 80 mm in diameter. The test specimen was stretched by pushing stretching member A (70 mm outer peripheral diameter, spoke-shaped, with 15 evenly spaced 10 mm-wide PP bands on the outer rim of the spokes) upward from the side opposite the ceramic chip-attached side toward the thickness of the tape at a speed of 1 mm / s and a maximum travel distance of 8 cm. When all the ceramic chips were peeled from the tape, the elongation at peeling of the tape was calculated using the following formula (3). Whether the ceramic chips had peeled off was determined by poking the ceramic chips from the side with a 50 μm-thick PET film and evaluating the following criteria. (Judgment) ◎: The ceramic chip slid (peel) without resistance when the movement distance was 55 mm or less. ○: The ceramic chip slid (peel) without resistance when the movement distance was 70 mm or less. △: The ceramic chip peeled off with some resistance when the movement distance was 70 mm. ×: Cannot be peeled off. Not adhered: The ceramic chip was not attached (fixed) to the tape before the test piece was stretched. The elongation at peeling was calculated using the following formula (3): the length of the side of the central square of the 10 mm square grid marks that were marked on the tape in advance when the test specimens were prepared in the above "Chip cuttability" was defined as the "initial gauge length," and the length of the side of the central square when all the ceramic chips had peeled off was defined as the gauge length. Elongation at peeling [%] = {(gauge length of the tape after elongation when all the ceramic chips have peeled off) / (initial gauge length)} × 100 Formula (3)

[0256] <Surface adhesive strength before stretching (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.

[0257] Surface adhesion strength at elongation <200% (P 200 )> 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 tape was cut to 30 mm x 50 mm, and a gauge line was written 10 mm from each longitudinal end to prepare the test specimen. The test specimen had a gauge line distance of 30 mm (= 50 mm - 10 mm x 2) before elongation (initial gauge line distance). The test specimen was stretched in the longitudinal direction until the gauge line distance reached 90 mm (the elongation calculated by the following formula (4) was 200%), 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 of a stainless steel block (10 mm x 10 mm x 40 mm in size, with the 10 mm x 10 mm surface designated as the bottom) was pressed against the exposed surface of the 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 200% elongation was 200 It was decided. Elongation (%) = {(gauge length after elongation) - (gauge length before elongation)} / (gauge length before elongation) × 100 Formula (4)

[0258] Surface adhesion strength at <300% elongation (P 300 )> The test piece was stretched in the longitudinal direction until the gauge length was 120 mm (the elongation calculated by the above formula (2) was 300%), and then the test piece was attached to the strong adhesive double-sided tape of the test stage so that the adhesive layer of the test piece was on the opposite side to the stainless steel plate. 200 The surface adhesive strength P when the stainless steel square bar is stretched 300% is measured in the same way as above. 300 It was decided.

[0259] <Surface adhesion reduction rate> Surface adhesive force P when stretched 300% compared to surface adhesive force P0 before stretching 300 The rate of decrease was calculated using the following formula. Surface adhesion reduction rate (%)=[(P0-P 300 ) / P0]×100%...Equation (5)

[0260] 2. Tape manufacturing [material] The materials and preparation methods used in the examples and comparative examples are as follows.

[0261] <<Base polymer>> Base polymer (1) A pressure vessel was purged with nitrogen and dried. 4 L of cyclohexane, 9.6 mL of sec-butyllithium (10% by mass solution in cyclohexane), and 0.9 mL of ethylene glycol dimethyl ether were added as the solvent. The vessel was heated to 60°C, and 100 mL of styrene was added and polymerized for 60 minutes. At the same temperature, 1.10 L of butadiene was then added and polymerized for 90 minutes. Subsequently, 100 mL of styrene was added at the same temperature and polymerized for 60 minutes. After that, 3.5 L of methanol was added to terminate the polymerization, yielding a polymerization reaction solution containing a block copolymer. Palladium carbon (palladium loading: 5% by mass) was added as a hydrogenation catalyst to this polymerization reaction solution, and the reaction was carried out for 10 hours under conditions of 2 MPa hydrogen pressure and 150°C. After cooling and depressurization, the palladium carbon was removed by filtration. The filtrate was concentrated and further dried in vacuo to obtain base polymer (1). The base polymer (1) was a hydrogenated polystyrene-polybutadiene-polystyrene block copolymer (styrene-ethylene-butylene-styrene block copolymer, hereinafter sometimes referred to as "SEBS") with a styrene content of 22% by mass, a weight-average molecular weight of 126,000, and a specific gravity of 0.91. A solution of the base polymer (1) dissolved in toluene was applied to a release liner (Film Vina 50E-0010GT, manufactured by Fujimori Kogyo Co., Ltd.) with an applicator so that the thickness after drying was 50 μm. The sheet dried at 80°C for 3 minutes had a 100% modulus of 2.3 MPa, a stress at break of 20.6 MPa, and a Shore A (Type A) hardness of 77.

[0262] Base polymer (2) A pressure vessel was purged with nitrogen and dried. 3,000 mL of cyclohexane and 9.2 mL of sec-butyllithium (10.5% by mass solution 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 mass) 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 under vacuum to obtain base polymer (2). The base polymer (2) was a hydrogenated polystyrene-polyisoprene / butadiene-polystyrene block copolymer (styrene-ethylene-ethylene-propylene-styrene block copolymer, hereinafter sometimes referred to as "SEEPS") with a styrene content of 30% by mass, a weight-average molecular weight of 98,000, and a specific gravity of 0.91. A solution of the base polymer (2) dissolved in toluene was applied to a release liner (Film Vina 50E-0010GT, manufactured by Fujimori Kogyo Co., Ltd.) with an applicator so that the thickness after drying was 50 μm. The sheet dried at 80°C for 3 minutes had a 100% modulus of 2.2 MPa, a stress at break of 35.3 MPa, and a Shore A (Type A) hardness of 75.

[0263] Base polymer (3) A styrene-ethylene-propylene copolymer (Septon 1020 manufactured by Kuraray Co., Ltd., hereinafter sometimes referred to as "SEP"; styrene content: 36% by mass, specific gravity: 0.91) was used as the base polymer (3). A solution of the base polymer (3) dissolved in toluene was applied to a release liner (Film Vina 50E-0010GT manufactured by Fujimori Kogyo Co., Ltd.) with an applicator so that the thickness after drying was 50 μm. The sheet dried at 80°C for 3 minutes had a 100% modulus of 2.0 MPa, a stress at break of 15.3 MPa, and a Shore A (Type A) hardness of 70.

[0264] Base polymer (4) A styrene-ethylene-propylene-styrene copolymer (Septon 2063 manufactured by Kuraray Co., Ltd., hereinafter sometimes referred to as "SEPS"; styrene content: 13% by mass, specific gravity: 0.91) was used as the base polymer (4). A solution of the base polymer (4) dissolved in toluene was applied to a release liner (Film Vina 50E-0010GT manufactured by Fujimori Kogyo Co., Ltd.) with an applicator so that the thickness after drying was 50 μm. The sheet dried at 80°C for 3 minutes had a 100% modulus of 0.5 MPa, a stress at break of 10.8 MPa, and a Shore A (Type A) hardness of 36.

[0265] <<Tackifying resin>> The following tackifying resins (1) to (3) were used.

[0266] [Table 1]

[0267] <<Polymerizable compounds>> The following compounds (1) to (3) were used as polymerizable compounds.

[0268] [Table 2]

[0269] <<Photopolymerization initiator>> As the photopolymerization initiator (1), Omnirad 184 (manufactured by IGM Resins BV) was used.

[0270] <<Filler>> The following filler (1) was used:

[0271] [Table 3]

[0272] The specific gravities of the base polymer, tackifier resin, polymerizable compound, and filler were measured according to the method of JIS K7112, and the content (volume ratio) of the filler in the adhesive composition (solid content) was calculated using the following formula. {(Filler mass) / (Filler specific gravity)} = Filler volume {(Volume of filler) / (Total volume of adhesive composition (solid content))}×100=Content of filler in adhesive layer [volume %]

[0273] <<Adhesive composition>> Adhesive composition (1) 100 parts by mass of the base polymer (1), 100 parts by mass of the tackifier resin (1), 30 parts by mass of the polymerizable compound (1), 8 parts by mass of the photopolymerization initiator (1), 60.5 parts by mass of the filler (1), and toluene were added and stirred and mixed to homogeneity to obtain a pressure-sensitive adhesive composition (1) with a solid content of 25% by mass.

[0274] Pressure-sensitive adhesive compositions (2) to (11) The adhesive composition was prepared in the same manner as in the case of the above adhesive composition (1) according to the compounding ratios shown in the following table of the following examples.

[0275] [Table 4]

[0276] <<Resin composition for forming intermediate layer>> ·Resin composition for forming intermediate layer (1) A reaction vessel equipped with a stirrer, reflux condenser, nitrogen inlet, thermometer, and dropping funnel was charged with 75.94 parts by weight of n-butyl acrylate, 5 parts by weight of 2-ethylhexyl acrylate, 15 parts by weight of cyclohexyl acrylate, 4 parts by weight of acrylic acid, 0.06 parts by weight of 4-hydroxybutyl acrylate, and 200 parts by weight of ethyl acetate. The mixture was stirred and heated to 65°C while blowing in nitrogen to obtain mixture (1). Next, 4 parts by weight of 2,2'-azobisisobutyronitrile solution (2.5% solids) dissolved in ethyl acetate was added to the mixture (1), and the mixture was stirred and held at 65°C for 10 hours to obtain mixture (2). Next, mixture (2) was diluted with ethyl acetate to a solids content of 30% by weight and filtered through a 200-mesh wire mesh to obtain a solution of acrylic copolymer (1) with a weight-average molecular weight of 1.6 million (polystyrene equivalent). To 100 parts by mass (solid content) of the acrylic copolymer (1), 2.0 parts by mass of an epoxy-based crosslinking agent (a solution with a solid content of 5% by mass obtained by mixing Tetrad X manufactured by Mitsubishi Gas Chemical Company, Inc. and ethyl acetate) was added, and the mixture was stirred and mixed uniformly to obtain a resin composition (1) for forming an intermediate layer, which is an acrylic adhesive 1.

[0277] <<Base material>> ·Base material (1) The substrate (1) used was an ester-based polyurethane resin film (Esmer URS, manufactured by Nihon Matai Co., Ltd., thickness 100 μm). The substrate (1) had a 100% modulus of 8.56 MPa, a 200% modulus of 11.27 MPa, a 300% modulus of 22.84 MPa, an elongation at break of 556%, a stress at break of 91.0 MPa, and a rubber hardness of 92 Shore A (Type A).

[0278] ·Base material (2) Substrate (2) was produced by melting a thermoplastic polyester elastomer (Hytrel 5557, manufactured by Toray Celanese Co., Ltd.) at 240°C using a T-die extruder (single-screw extruder D2020, D (mm) = 20, L / D = 20, die: 300 mm wide coat hanger die, manufactured by Toyo Seiki Seisaku-sho, Ltd.) and extruding it to an average thickness of 100 μm. The substrate (2) had a 100% modulus of 10.47 MPa, a 200% modulus of 11.52 MPa, a 300% modulus of 15.82 MPa, an elongation at break of 701%, a stress at break of 67.14 MPa, and a rubber hardness of 55 Shore D (type D).

[0279] [Adhesive tape manufacturing] (Example 1) The resin composition (1) for forming an intermediate layer was applied to a release liner (1) (Film Vina 75E-0010GT, manufactured by Fujimori Kogyo Co., Ltd.) with an applicator so that the thickness after drying would be 10 μm, and an intermediate layer was prepared by drying for 3 minutes at 80° C. The intermediate layer was attached to a substrate (1) that had been corona-treated so that the wet tension would be 56 mN / m, and laminated under a pressure of 0.2 MPa to prepare a laminated intermediate.

[0280] The pressure-sensitive adhesive composition (1) was applied to a release liner (2) (Film Vina 50E-0010GT, manufactured by Fujimori Kogyo Co., Ltd.) using an applicator so that the thickness after drying would be 30 μm, and then dried at 80°C for 3 minutes. The adhesive composition was then applied to a release liner (2) using an ultraviolet irradiation device (Fusion UV Systems Japan Co., Ltd. "F450", lamp: 120 W / cm, H bulb) with an irradiation dose of 1000 mJ / cm. 2 The adhesive layer (1) was then irradiated with ultraviolet light at a temperature of 100°C to form a pressure-sensitive adhesive layer (1). The release liner (1) of the laminated intermediate was then peeled off, and the pressure-sensitive adhesive layer (1) was attached to the exposed surface of the intermediate layer, followed by lamination under a pressure of 0.2 MPa to form a tape of Example 1.

[0281] (Examples 2 to 11) Tapes of Examples 2 to 11 were prepared in the same manner as in Example 1, except that the pressure-sensitive adhesive composition (1) was replaced with any of the pressure-sensitive adhesive compositions (2) to (11).

[0282] The evaluation results of Examples 1 to 11 are shown in the table below.

[0283] [Table 5]

[0284] [Table 6] [Explanation of symbols]

[0285] 1...Temporary fixing tape, 2...Base material, 3...Adhesive layer, 5...Component, 200...Transfer receiving body, D...Stretching direction

Claims

1. A temporary fixing tape having at least a pressure-sensitive adhesive layer, the pressure-sensitive adhesive layer contains an elongated crystalline resin and a polymer of a polymerizable compound, The temporary fixing tape has a total content of the polymerizable compound and a polymer of the polymerizable compound of 4 parts by mass or more and less than 50 parts by mass per 100 parts by mass of the stretched crystalline resin.

2. A temporary fixing tape having at least a pressure-sensitive adhesive layer, the pressure-sensitive adhesive layer contains an elongated crystalline resin and a polymer of a polymerizable compound, A temporary fixing tape, wherein the absolute value of the difference between the 100% modulus and the 300% modulus of the pressure-sensitive adhesive layer is 0.5 or more.

3. A temporary fixing tape having at least a pressure-sensitive adhesive layer, the pressure-sensitive adhesive layer contains an elongated crystalline resin and a polymer of a polymerizable compound, The 100% modulus of the pressure-sensitive adhesive layer is 4.5 or less, A temporary fixing tape, wherein the 300% modulus of the pressure-sensitive adhesive layer is greater than 1.

0.

4. The temporary fixing tape according to any one of claims 1 to 3, wherein the polymerizable compound is an active energy ray-curable polymerizable compound.

5. The temporary fixing tape according to any one of claims 1 to 3, wherein the polymerizable compound is a polyfunctional (meth)acrylate.

6. the stretched crystalline resin is a block copolymer (A′) having at least a polymer block A and a polymer block B, The temporary fixing tape according to any one of claims 1 to 3, wherein the polymer block B has at least a block containing a structural unit b1 having a crystalline skeleton.

7. The temporary fixing tape according to claim 6, wherein the structural unit b1 having a crystalline skeleton is a linear hydrocarbon structural unit.

8. The temporary fixing tape according to claim 6 , wherein the polymer block B further comprises a block containing a structural unit b2 having a non-crystalline skeleton.

9. The temporary fixing tape according to claim 8 , wherein the structural unit b2 having an amorphous skeleton is a branched hydrocarbon structural unit.

10. The temporary fixing tape according to claim 6, wherein the content of the polymer block B in the block copolymer (A') is 10% by mass to 95% by mass.

11. The temporary fixing tape according to claim 6 , wherein the polymer block A has an aromatic ring structure.

12. 4. The temporary fixing tape according to claim 1, wherein said stretch-induced crystalline resin contains at least one of a styrene-ethylene-butylene-styrene copolymer and a styrene-ethylene-ethylene-propylene-styrene copolymer.

13. The temporary fixing tape according to any one of claims 1 to 3, wherein the pressure-sensitive adhesive layer further contains a filler.

14. The temporary fixing tape according to any one of claims 1 to 3, wherein the pressure-sensitive adhesive layer is provided on at least one surface of an extensible substrate.

15. A method for manufacturing a component using the temporary fixing tape according to any one of claims 1 to 3, A method for manufacturing a component, comprising a peeling step of stretching the temporary fixing tape, to which one or more components are fixed, in at least one direction to peel the components from the temporary fixing tape.

16. The surface area of ​​the surface of each component that comes into contact with the temporary fixing tape in the peeling step is 1 mm ２ 16. The method of claim 15, wherein:

17. The method for manufacturing a component according to claim 15, wherein the component is a multilayer ceramic capacitor, a semiconductor element, an inductor, or a chip.

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