Adhesive member, adhesive material kit, copolymer, composition containing said copolymer, and composition containing monomer

Abstract

The adhesive member contains a copolymer in which a structural unit A is represented by formula (I) (In the formula, R1 represents a hydrogen atom or a methyl; L1 represents a single bond, -O-, etc.; W1 represents a single bond or a C1-20 alkylene; R2 represents a methyl, a hydroxyl, an optionally substituted C1-6 alkoxy, etc.) and a structural unit B is represented by formula (II) (In the formula, R3 represents a hydrogen atom or a methyl; W2 represents a C1-20 alkylene in which at least one hydrogen atom has been substituted by a hydroxyl; L2 represents a single bond, -O-, etc.; W3 represents a single bond, C1-6 alkylene, etc.; R4 and R5 each independently represent a hydrogen atom or a hydroxyl; however, R4 and R5 are not both hydrogen atoms.).

Description

Adhesive member, adhesive kit, copolymer, composition containing the copolymer, and composition containing a monomer

[0001] The present invention relates to an adhesive member, an adhesive member kit including the adhesive member and a water-containing adhesive enhancer, a copolymer including specific structural units A1, A2 and structural unit B, a composition including the copolymer, and a composition including monomer α and monomer β.

[0002] Adhesive tapes are used in various industrial fields, such as home appliances, automobiles, office automation equipment, and construction, as a joining means with good workability and highly reliable adhesion. In recent years, there has been a demand for adhesive materials that can exhibit sufficient adhesive performance even under water or wet conditions. However, it is generally difficult to obtain sufficient adhesive performance when the surface of the object to be bonded is wet.

[0003] Patent Document 1 discloses a pressure-sensitive adhesive that has sufficient adhesive strength even when applied to a wet surface. This pressure-sensitive adhesive is mainly characterized by containing an acrylic resin (A) obtained by copolymerizing copolymer components (a) including 0.01 to 50 mass% of an acrylic monomer (a1) having a specific structure, 0.1 to 30 mass% of a copolymerizable monomer (a2) having a hydroxyl group and / or a carboxyl group excluding (a1), and 40 to 99 mass% of a (meth)acrylic acid alkyl ester monomer (a3) ​​having an alkyl group having 1 to 20 carbon atoms, and a crosslinking agent (B).

[0004] Furthermore, Patent Document 2 discloses a curable resin composition that can be used as a material for adhesive tape or the like that can firmly bond to a variety of materials, and that contains a monomer A having a (meth)acryloyl group and a monomer B represented by 2-(acryloyloxy)ethyl 3,4-dihydroxybenzoate (DHBA-HEA).

[0005] JP 2022-135585 A JP 2022-086979 A

[0006] The adhesive strength of the adhesive described in Patent Document 1 when applied to a wet surface is only about 80% of that when applied to a dry surface. Therefore, it is difficult to say that the adhesive described in Patent Document 1, and in particular the acrylic resin (A), one of its main components, exhibit sufficient adhesive strength depending on the application. Furthermore, the curable resin composition described in Patent Document 2 does not particularly mention adhesion to wet surfaces.

[0007] Therefore, a primary object of the present invention is to provide a PSA member that exhibits good adhesive strength even when used under wet conditions. Another object of the present invention is to provide a PSA kit that includes a copolymer, which is one of the main components of the PSA member, the PSA member, and an adhesive enhancer containing water, and a composition from which the PSA member can be obtained.

[0008] That is, the present invention relates to the following [1] to [6]. [1] A pressure-sensitive adhesive member comprising a copolymer having a structural unit A and a structural unit B, wherein the structural unit A is represented by the following formula (I): [In the formula, R １ represents a hydrogen atom or methyl; １ represents a single bond, —O—, —NH—, or —NR ６ -, -NHC(O)O-, or -NHC(O)NH-; W １ is a single bond, or C １－２０ represents alkylene; ２ is methyl, hydroxyl, optionally substituted C １－６ R represents alkoxy, optionally substituted phenyl, optionally substituted phenoxy, optionally substituted 5- or 6-membered heteroaryl, optionally substituted 3- to 8-membered saturated or partially unsaturated hydrocarbon ring, optionally substituted 3- to 8-membered saturated or partially unsaturated heterocycle, or (meth)acryloyloxy; ６ is an optionally substituted C １－８ and the structural unit B is one or more of the structural units represented by the following formula (II): [In the formula, R ３ represents a hydrogen atom or methyl;２ is a C in which at least one hydrogen atom is replaced by hydroxyl １－２０ represents alkylene; ２ represents a single bond, —O—, —CH(OH)—, —C(O)O—, —OC(O)—, or —OC(O)O—; W ３ is a single bond, C １－６ Alkylene, C ２－６ represents alkenylene; R ４ and R ５ each independently represents a hydrogen atom or a hydroxyl; ４ and R ５ and none of the structural units A is a hydrogen atom. ２ is methyl; and the R ２ [3] The pressure-sensitive adhesive member according to [1], wherein the structural unit B is a structural unit A2 in which R ４ and the R ５ [4] The pressure-sensitive adhesive member according to [1] or [2], which contains a structural unit B1 in which R is hydroxyl. [4] The pressure-sensitive adhesive member according to [1] to [3], in which the content of the structural unit B is 1% by mass or more and 20% by mass or less. [5] The pressure-sensitive adhesive member according to [1] to [4], which is a film. [6] An adhesive kit comprising the pressure-sensitive adhesive member according to [1] to [5], and an adhesive enhancer containing water. [7] A copolymer having a structural unit A and a structural unit B, in which the structural unit A is represented by the following formula (I): [In the formula, R １ represents a hydrogen atom or methyl; １ represents a single bond, —O—, —NH—, or —NR ６ -, -NHC(O)O-, or -NHC(O)NH-; W １ is a single bond, or C １－２０ represents alkylene; ２ is methyl, hydroxyl, optionally substituted C １－６R represents alkoxy, optionally substituted phenyl, optionally substituted phenoxy, optionally substituted 5- or 6-membered heteroaryl, optionally substituted 3- to 8-membered saturated or partially unsaturated hydrocarbon ring, optionally substituted 3- to 8-membered saturated or partially unsaturated heterocycle, or (meth)acryloyloxy; ６ is an optionally substituted C １－８ and the structural unit B is one or more of the structural units represented by the following formula (II): [In the formula, R ３ represents a hydrogen atom or methyl; ２ is a C in which at least one hydrogen atom is replaced by hydroxyl １－２０ represents alkylene; ２ represents a single bond, —O—, —CH(OH)—, —C(O)O—, —OC(O)—, or —OC(O)O—; W ３ is a single bond, C １－６ Alkylene, C ２－６ represents alkenylene; R ４ and R ５ each independently represents a hydrogen atom or a hydroxyl; ４ and R ５ and none of the structural units A is a hydrogen atom, ２ is methyl; and the R ２ and a structural unit A2 in which R is hydroxyl. [8] A composition comprising the copolymer according to [7]. [9] A composition comprising a monomer α and a monomer β, wherein the monomer α is represented by the following formula (I'): [In the formula, R １ represents a hydrogen atom or methyl; １ represents a single bond, —O—, —NH—, or —NR ６ -, -NHC(O)O-, or -NHC(O)NH-; W １ is a single bond, or C １－２０ represents alkylene; ２ is methyl, hydroxyl, optionally substituted C１－６ R represents alkoxy, optionally substituted phenyl, optionally substituted phenoxy, optionally substituted 5- or 6-membered heteroaryl, optionally substituted 3- to 8-membered saturated or partially unsaturated hydrocarbon ring, optionally substituted 3- to 8-membered saturated or partially unsaturated heterocycle, or (meth)acryloyloxy; ６ is an optionally substituted C １－８ and the monomer β is one or more of the following formula (II′): [In the formula, R ３ represents a hydrogen atom or methyl; ２ is a C in which at least one hydrogen atom is replaced by hydroxyl １－２０ represents alkylene; ２ represents a single bond, —O—, —CH(OH)—, —C(O)O—, —OC(O)—, or —OC(O)O—; W ３ is a single bond, C １－６ Alkylene, C ２－６ represents alkenylene; R ４ and R ５ each independently represents a hydrogen atom or a hydroxyl; ４ and R ５ and none of the R ２ is methyl, and ２ and a monomer A2' in which is hydroxyl.

[0009] The PSA-based adhesive of the present invention can exhibit good adhesive strength when used under wet conditions on substrates made of specific materials. Furthermore, the present invention can provide an adhesive kit including a copolymer, which is one of the main components of the PSA-based adhesive of the present invention, the PSA-based adhesive, and an adhesive enhancer containing water, as well as a composition from which the PSA-based adhesive can be obtained.

[0010] The present invention will be described in detail below, but these are examples of preferred embodiments. First, the terms used in this specification will be explained.

[0011] In this specification, when a numerical range is indicated using "to," it is intended to include both ends of the range.

[0012] "(Meth)acrylic" means acrylic or methacrylic, "(meth)acryloyl" means acryloyl or methacryloyl, and "(meth)acrylate" means acrylate or methacrylate. "(Meth)acryloyloxy" includes methacryloyloxy and acryloyloxy groups.

[0013] The number of carbon atoms in the definition of "substituent" can be changed to, for example, "C １－６ " etc. Specifically, "C １－６ The term "alkyl" is synonymous with an alkyl group having 1 to 6 carbon atoms.

[0014] "C １－２０ "Alkylene" means a linear or branched divalent saturated hydrocarbon group having 1 to 20 carbon atoms. ３－２０ alkylene," and more preferably, "C １－８ alkylene," and more preferably, "C １－６ alkylene," and most preferably "C １－４ "C alkylene". １－２０ Specific examples of "alkylene" include methylene, ethylene, trimethylene, tetramethylene, hexamethylene, octamethylene, 1-methylmethylene, 1-ethylmethylene, 1-propylmethylene, 1-methylethylene, 2-methylethylene, and 1-ethylethylene.

[0015] "C ２－６ "Alkenylene" means a straight or branched chain, double-bonded divalent hydrocarbon group having 2 to 6 carbon atoms. ２－４ "C alkylene". ２－６Specific examples of "alkenylene" include ethylenylene, propylenylene, butylenylene, pentalenylene, hexalenylene, 1-methylethynylene, 2-methylethynylene, 1-methylpropynylene, and the like.

[0016] "C １－６ "Alkoxy" has C on the oxygen atom １－６ It means a substituent group to which an alkyl is attached, and which is attached to the parent molecule by an oxygen atom. １－６ "C" in "Alkoxy" １－６ The "C alkyl" moiety is １－６ It is synonymous with "alkyl". Preferably, "C １－４ "Alkoxy". １－６ Specific examples of "alkoxy" include methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, sec-butoxy, tert-butoxy, pentyloxy, hexyloxy, and the like.

[0017] Examples of "5- or 6-membered heteroaryl" include 5- or 6-membered monocyclic aromatic heterocycles, and the groups contain one or more (e.g., 1 to 4) heteroatoms of the same or different types selected from nitrogen, sulfur, and oxygen atoms as ring-constituting atoms. Specific examples of "5- or 6-membered heteroaryl" include pyridyl, pyrimidyl, pyrazyl, pyridazyl, triazyl, imidazolyl, pyrazolyl, triazoyl, tetrazoyl, oxazolyl, thiazolyl, isoxazolyl, isothiazolyl, and the like.

[0018] Examples of the "3- to 8-membered saturated or partially unsaturated hydrocarbon group" include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclopentenyl, cyclohexenyl, cyclohexadienyl, and the like.

[0019] Examples of "3- to 8-membered saturated or partially unsaturated heterocycles" include 3- to 8-membered monocyclic saturated or partially unsaturated heterocycles containing 1 to 3 heteroatoms of the same or different types selected from nitrogen atoms, oxygen atoms, and sulfur atoms as ring-constituting atoms. Preferred are 4- to 6-membered saturated or partially unsaturated heterocycles, more preferably 4- to 6-membered saturated or partially unsaturated heterocycles containing 1 to 2 oxygen atoms as ring-constituting atoms, and even more preferably 4- to 6-membered saturated heterocycles containing 1 to 2 oxygen atoms as ring-constituting atoms. Specific examples of the "3- to 8-membered saturated or partially unsaturated heterocycle" include oxiranyl, oxetanyl, tetrahydrofuryl, dihydrofuryl, pyranyl, dihydropyranyl, tetrahydropyranyl, dioxanyl, dioxolanyl, oxazolidinyl, oxepanyl, oxecanyl, aziridinyl, azetidinyl, pyrrolidinyl, piperidinyl, piperazinyl, azepanyl, azecanyl, morpholinyl, thiomorpholinyl, etc., with oxetanyl, tetrahydrofuryl, tetrahydropyranyl, dioxanyl, and dioxolanyl being preferred, and tetrahydrofuryl and dioxolanyl being more preferred. The bond of the group may be either a carbon atom or a nitrogen atom constituting the ring.

[0020] Examples of "3- to 8-membered oxygen-containing saturated heterocycles" include 3- to 8-membered monocyclic saturated heterocycles containing 1 or 2 oxygen atoms and, optionally, 1 or 2 atoms of the same or different kind selected from nitrogen atoms and sulfur atoms. The oxygen atom, nitrogen atom, and sulfur atom are all atoms constituting the ring. 4- to 6-membered oxygen-containing saturated heterocycles are preferred. Specific examples include oxiranyl, oxetanyl, tetrahydrofuryl, tetrahydropyranyl, dioxanyl, dioxolanyl, oxazolidinyl, oxepanyl, oxecanyl, and morpholinyl; oxetanyl, tetrahydrofuryl, tetrahydropyranyl, dioxanyl, and dioxolanyl are preferred; oxetanyl and tetrahydrofuryl are more preferred.

[0021] "Optionally substituted C １－６The substituents in "alkoxy" include hydroxyl, halogen atoms, C １－６ Alkoxy and the like.

[0022] Examples of the substituents in the "optionally substituted phenyl", "optionally substituted phenoxy", "optionally substituted 5- or 6-membered heteroaryl", "optionally substituted 3- to 8-membered saturated or partially unsaturated hydrocarbon ring", and "optionally substituted 3- to 8-membered saturated or partially unsaturated heterocycle" include hydroxyl, amino, a halogen atom, C １－６ Alkyl, C １－６ Alkoxy and the like.

[0023] Specific examples of the "halogen atom" include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0024] [Adhesive member] The adhesive member of this embodiment contains the copolymer of this embodiment having the structural unit A and the structural unit B. Here, "the adhesive member of this embodiment contains the copolymer of this embodiment" means that the copolymer itself is contained in the adhesive member, and also includes the case where a polymer compound having a structure derived from the copolymer is contained in the adhesive member. An example of the polymer compound having a structure derived from the copolymer is a polymer compound obtained by reacting the copolymer of this embodiment with a crosslinking agent described below.

[0025] The adhesive member of the present embodiment refers to a material that is interposed between adherends, for example, by adhering one side to one substrate and the other side to the other substrate, thereby preventing one substrate from moving relative to the other substrate (hereinafter sometimes referred to as "fixing"). Preventing one substrate from moving relative to the other substrate does not only mean that one substrate does not move at all relative to the other substrate when a certain force is applied, but also includes fixing one substrate so that it is allowed to move within a certain range relative to the other substrate. The certain range may be determined based on the location and intended use of the two substrates. The certain force can also be set according to the intended use of the adhesive member. Adhesive members are sometimes used in place of joining methods such as bolt fastening or welding, from the perspective of weight reduction and simplified operation. Furthermore, flexible adhesive members are suitable for applications requiring vibration resistance, etc. The adhesive member of the present embodiment has tack at 25°C (room temperature) and adheres to an adherend (substrate) with light pressure, such as pressing the substrate with a hand.

[0026] As a result of investigations by the present inventors, it was found that the adhesive strength of the conventional adhesive films described in Patent Document 1 and the like decreases with respect to various substrates under wet conditions, such as when water is present on the adhesive film's surface. On the other hand, the present inventors have found that the adhesive member of the present embodiment, when used on a substrate made of a specific material (especially an iron-based material), exhibits improved adhesive strength under wet conditions compared to dry conditions. The present invention is based on this finding.

[0027] Hereinafter, the copolymer of this embodiment, which is the main component of the PSA member of this embodiment, will first be described in detail, and then other components of the PSA member of this embodiment, a manufacturing method, a method of use, etc. will be described.

[0028] <Copolymer> The copolymer of the present invention is a copolymer having a structural unit A and a structural unit B. Each structural unit constituting the copolymer will be described in detail below.

[0029] <<Structural Unit A>> The structural unit A is one of the structural units that constitute the copolymer, and is represented by the following formula (I).

[0030] [In the formula, R １ represents a hydrogen atom or methyl; １ represents a single bond, —O—, —NH—, or —NR ６ -, -NHC(O)O-, or -NHC(O)NH-; W １ is a single bond, or C １－２０ represents alkylene; ２ is methyl, hydroxyl, optionally substituted C １－６ R represents alkoxy, optionally substituted phenyl, optionally substituted phenoxy, optionally substituted 5- or 6-membered heteroaryl, optionally substituted 3- to 8-membered saturated or partially unsaturated hydrocarbon ring, optionally substituted 3- to 8-membered saturated or partially unsaturated heterocycle, or (meth)acryloyloxy; ６ is an optionally substituted C １－８ represents alkyl].

[0031] L １ From the viewpoint of ease of production, etc., is preferably a single bond or —O—; more preferably —O—.

[0032] W １ is preferably a single bond or C １－６ alkylene; more preferably a single bond, or C １－４ It is alkylene. １ In another embodiment of the present invention, １－８ Alkylene, C １－６ Alkylene, C ２－６ Alkylene, C １－４ Alkylene, C ２－４ alkylene and the like.

[0033] R ２ is preferably methyl, hydroxyl, optionally substituted C １－６ Alkoxy, e.g., hydroxyl or C １－６C optionally substituted with alkoxy １－６ Alkoxy, optionally substituted phenyl, optionally substituted 3- to 8-membered saturated heterocycle, such as a halogen atom, hydroxyl, C １－６ Alkyl, and C １－６ a 4- to 7-membered oxygen-containing saturated heterocycle (e.g., oxetanyl, tetrahydrofuryl, tetrahydropyranyl, dioxanyl, dioxolanyl, oxazolidinyl, oxepanyl, morpholinyl, etc.) optionally substituted with 1 to 4 identical or different groups selected from the group consisting of alkoxy, or (meth)acryloyloxy; more preferably, methyl, hydroxyl, C １－４ alkoxy, optionally substituted phenyl, 1 to 4 C １－６ a 4- to 7-membered oxygen-containing saturated heterocycle optionally substituted with alkyl; １－４ Alkoxy, 1 to 4 C １－６ It is a 4- to 6-membered oxygen-containing saturated heterocycle optionally substituted with alkyl, or phenyl.

[0034] From the viewpoint of adhesion, it is possible to select the structural unit A to be used according to the material of the substrate to be fixed. For organic substrates, R ２ It is preferable to use a copolymer containing a structural unit A which is a 3- to 8-membered oxygen-containing saturated heterocycle which may be substituted with R ２ It is preferred to use building block A in which is hydroxyl.

[0035] The copolymer in this embodiment is R ２ A structural unit A1 in which R is methyl ２ It is preferable that the structural unit A contains at least one of the structural unit A2 in which R is hydroxyl, and it is more preferable that the structural unit A contains both of these. ２ A structural unit A1 in which R is methyl ２ By including the structural unit A2 in which R is hydroxyl, the adhesiveness of the pressure-sensitive adhesive containing the copolymer is easily exhibited.

[0036] L in structural unit A1 １ , W １Although there are no particular limitations on the preferred embodiments of the structural unit A, examples include the preferred embodiments of the structural unit A described above. １ is -O-, and W １ is a single bond, or C １－６ alkylene, and R ２ It is preferred that the structural unit is a structural unit in which R is methyl.

[0037] L in structural unit A2 １ , W １ Although there are no particular limitations on the preferred embodiments of the structural unit A, examples include the preferred embodiments of the structural unit A described above. １ and W １ is a single bond, and R ２ is a hydroxyl structural unit, and L １ is -O-, and W １ is C ２－２０ alkylene, and R ２ is a hydroxyl group.

[0038] The proportion of the structural unit A in the copolymer in this embodiment is not particularly limited, and can be the remainder excluding the structural unit B described below and other structural units. In particular, from the viewpoint of easily exhibiting the function of the structural unit A in the copolymer, the amount of the structural unit A is preferably 50% by mass or more, more preferably 60% by mass or more, and even more preferably 70% by mass or more, relative to the total amount of the copolymer. Examples of such properties include flexibility and insulating properties. In order to ensure the content of the structural unit B, the upper limit of the content of the structural unit A in the copolymer is preferably 98% by mass or less, more preferably 95% by mass or less.

[0039] When the copolymer of this embodiment contains the structural unit A1, the lower limit of the amount of the structural unit A1 in the copolymer is preferably 70% by mass or more, more preferably 80% by mass or more, and even more preferably 85% by mass or more, relative to the total amount of the copolymer, from the viewpoint of easily allowing the functions of the structural unit A1 to be exerted in the copolymer. Also, the upper limit of the amount of the structural unit A1 in the copolymer is preferably 95% by mass or less, more preferably 90% by mass or less, from the viewpoint of easily allowing the functions of the other structural units to be exerted.

[0040] When the copolymer of this embodiment contains the structural unit A2, the lower limit of the amount of the structural unit A2 in the copolymer is preferably 3% by mass or more, more preferably 5% by mass or more, and even more preferably 8% by mass or more, from the viewpoint of easily allowing the functions of the structural unit A2 to be exerted in the copolymer. Also, the upper limit of the amount of the structural unit A2 in the copolymer is preferably 15% by mass or less, and more preferably 10% by mass or less, from the viewpoint of easily allowing the functions of the other structural units to be exerted.

[0041] When the copolymer in the present embodiment contains the structural unit A1 and the structural unit A2, the ratio of the structural unit A1 to the structural unit A2 (A1:A2 (mass ratio)) is not particularly limited, but from the viewpoint of obtaining a PSA having good adhesive strength, it is preferably 70:30 to 99:1, more preferably 80:20 to 95:5, and even more preferably 85:15 to 92:8.

[0042] <<Structural Unit B>> The structural unit B is one of the structural units that constitute the copolymer of this embodiment, and is represented by the following formula (II).

[0043] [In the formula, R ３ represents a hydrogen atom or methyl; ２ is a C in which at least one hydrogen atom is replaced by hydroxyl １－２０ represents alkylene; ２ represents a single bond, —O—, —CH(OH)—, —C(O)O—, —OC(O)—, or —OC(O)O—; W ３ is a single bond, C １－６ Alkylene, C ２－６ represents alkenylene; R ４and R ５ each independently represents a hydrogen atom or a hydroxyl; ４ and R ５ are not all hydrogen atoms]

[0044] L ２ From the viewpoint of ease of production, etc., is preferably —O—, —C(O)O—, —OC(O)—, or —OC(O)O—, and more preferably —OC(O)—.

[0045] W ２ is a C in which at least one hydrogen atom is substituted with hydroxyl and other hydrogen atoms are optionally substituted. １－２０ It may be an alkylene, preferably a C １－６ alkylene; more preferably, C ２－６ alkylene; more preferably, C in which at least one hydrogen atom is substituted with hydroxyl and other hydrogen atoms are optionally substituted. ２－４ It is alkylene. ２ is substituted with two or more hydroxyl groups １－２０ When it is an alkylene, the adhesiveness tends to be improved, and in particular, when it contains a structural unit A that does not have a hydroxyl group, the effect tends to be greater. ２ Preferably, has two or more hydroxyl groups.

[0046] W ３ is a single bond or C ２－６ Alkenylene is preferred.

[0047] R ４ and R ５ In terms of improving adhesion, at least one hydroxyl group is W ３ It is preferable that the positional relationship between the W and the W is para-positioned. ３ When is a single bond, L ２ The positional relationship with W ３ and L ２When both are single bonds, W ２ It is preferable that the hydroxyl is positioned in the para position relative to R. ４ and R ５ In this case, it is preferable that at least one hydroxyl is arranged in the same manner as above, and the other hydroxyl is arranged on a carbon atom adjacent to the carbon atom to which the hydroxyl arranged on the para position is bonded (i.e., arranged on the ortho position).

[0048] Another embodiment of the structural unit B is a structural unit represented by the formula (II), W ２ wherein at least one hydrogen atom is substituted with hydroxyl and other hydrogen atoms are optionally substituted. ２－６ alkylene, and L ２ is -OC(O)-, and W ３ is a single bond, or C ２－４ alkenylene, and R ４ and R ５ Preferably, the compound comprises one or more compounds in which:

[0049] The proportion of the structural unit B in the copolymer in this embodiment is not particularly limited, and can be the remainder excluding the structural unit A and other structural units, but is preferably 1% by mass or more, more preferably 3% by mass or more, and even more preferably 5% by mass or more, relative to the total amount of the copolymer. In order to ensure the content of the structural unit B, the upper limit of the content of the structural unit A in the copolymer is preferably 20% by mass or less, more preferably 15% by mass or less, and even more preferably 10% by mass or less.

[0050] <<Other Structural Units>> The copolymer in the present embodiment may contain other structural units in addition to the above-described structural unit A and structural unit B, as long as the purpose of the present disclosure is not impaired. Examples of other structural units include, but are not limited to, acrylates and methacrylates that are not included in structural unit A and structural unit B.

[0051] The content of the other structural units relative to the total amount of the copolymer is not particularly limited, and the remainder excluding the monomer A and the monomer B can be the content.

[0052] The above-mentioned respective structural units (structural unit A, structural unit B, and other structural units) may each be present in a single type, or in a combination of two or more types.

[0053] <<Other Structural Units>> The copolymer in the present embodiment may contain other structural units in addition to the above-described structural unit A and structural unit B, as long as the purpose of the present disclosure is not impaired. Examples of other structural units include, but are not limited to, acrylates and methacrylates that are not included in structural unit A and structural unit B.

[0054] The content of the other structural units relative to the total amount of the copolymer is not particularly limited, and the remainder excluding the monomer A and the monomer B can be the content.

[0055] The above-mentioned respective structural units (structural unit A, structural unit B, and other structural units) may each be present in a single type, or in a combination of two or more types.

[0056] The weight-average molecular weight (Mw) of the copolymer in this embodiment is not particularly limited, but from the viewpoint of ease of production, it is preferably 100,000 to 400,000, more preferably 110,000 to 200,000, and even more preferably 120,000 to 150,000. The number-average molecular weight (Mn) of the copolymer in this embodiment is not particularly limited, but from the viewpoint of ease of production, it is preferably 10,000 to 80,000, more preferably 20,000 to 60,000, and even more preferably 30,000 to 50,000. The molecular weight distribution (weight-average molecular weight (Mw) / number-average molecular weight (Mn)) of the copolymer in this embodiment is not particularly limited, but from the viewpoint of ease of production, it is preferably 1.0 to 5.0, more preferably 2.0 to 4.0, and even more preferably 3.0 to 3.5. The weight average molecular weight (Mw) and number average molecular weight (Mn) of the copolymer in this embodiment can be measured in terms of polystyrene using gel permeation chromatography (manufactured by Tosoh Corporation, product number: HLC-8320GPC, column: manufactured by Tosoh Corporation, product number: TSKgel GMHH-R, solvent: tetrahydrofuran, flow rate: 0.6 mL / min).

[0057] <<Method for Producing Copolymer>> The copolymer of the present embodiment can be obtained by using a composition of the present embodiment (hereinafter referred to as the “monomer composition”) containing a monomer α corresponding to the structural unit A, a monomer β corresponding to the structural unit B, and monomers corresponding to other structural units that are used as needed, and polymerizing each monomer component in the monomer composition.

[0058] The method for polymerizing each of the above-mentioned monomer components is not particularly limited, and examples thereof include bulk polymerization, solution polymerization, emulsion polymerization, suspension polymerization, etc. In particular, from the viewpoints of manufacturability, handleability, etc., bulk polymerization and solution polymerization are preferred, and solution polymerization is more preferred.

[0059] The order in which the monomers are blended when polymerizing the monomer components to produce a copolymer is not particularly limited. One example is blending monomer α, monomer β, and other monomers and then polymerizing the monomers to produce the copolymer. Another example is producing a first polymer by polymerizing precursor monomers, which are precursors of the monomers, and then reacting the first polymer with a compound to form each structural unit, thereby producing the copolymer of this embodiment. The precursor monomer may be used in place of any one of monomer α, monomer β, and other monomers, or may be used in place of all of the monomers.

[0060] (Monomer Composition) The monomer composition of the present embodiment is a composition containing monomer α and monomer β, where monomer α is one or more monomers represented by the following formula (I'), and monomer β is one or more monomers represented by the following formula (II').

[0061] [In the formula, R １ represents a hydrogen atom or methyl; １ represents a single bond, —O—, —NH—, or —NR ６ -, -NHC(O)O-, or -NHC(O)NH-; W １ is a single bond, or C １－２０ represents alkylene; ２ is methyl, hydroxyl, optionally substituted C １－６ R represents alkoxy, optionally substituted phenyl, optionally substituted phenoxy, optionally substituted 5- or 6-membered heteroaryl, optionally substituted 3- to 8-membered saturated or partially unsaturated hydrocarbon ring, optionally substituted 3- to 8-membered saturated or partially unsaturated heterocycle, or (meth)acryloyloxy; ６ is an optionally substituted C １－８ represents alkyl]

[0062] [In the formula, R ３ represents a hydrogen atom or methyl; ２ is a C in which at least one hydrogen atom is replaced by hydroxyl１－２０ represents alkylene; ２ represents a single bond, —O—, —CH(OH)—, —C(O)O—, —OC(O)—, or —OC(O)O—; W ３ is a single bond, C １－６ Alkylene, C ２－６ represents alkenylene; R ４ and R ５ each independently represents a hydrogen atom or a hydroxyl; ４ and R ５ are not all hydrogen atoms]

[0063] [Monomer α] Monomer α is synthesized by a method combining a known compound and a known synthesis method. Alternatively, a commercially available product may be used as monomer α. Furthermore, preferred embodiments of monomer α are the same as those of the structural unit A corresponding to monomer α.

[0064] From the viewpoint of allowing the resulting copolymer to exhibit the properties of structural unit A, the content of monomer α in the monomer components in the monomer composition is preferably 50% by mass or more, more preferably 60% by mass or more, and even more preferably 70% by mass or more. From the viewpoint of allowing the resulting copolymer to exhibit the properties of structural unit B, the content of monomer α in the monomer components in the monomer composition is preferably 98% by mass or less, and more preferably 95% by mass or less.

[0065] [Monomer β] Monomer β is synthesized by a method combining a known compound and a known synthesis method. Alternatively, a commercially available product may be used as monomer β. Furthermore, preferred embodiments of monomer β are the same as those of the structural unit α corresponding to monomer β.

[0066] From the viewpoint of allowing the resulting copolymer to exhibit the properties of structural unit B, the content of monomer β in the monomer components in the monomer composition is preferably 1% by mass or more, more preferably 3% by mass or more, and even more preferably 5% by mass or more. From the viewpoint of allowing the resulting copolymer to exhibit the properties of structural unit A, the content of monomer β in the monomer components in the monomer composition is preferably 20% by mass or less, more preferably 15% by mass or less, and even more preferably 10% by mass or less.

[0067] [Other Components] The monomer composition of the present embodiment may contain, in addition to the above-described monomer components (monomer α, monomer β), other monomers, polymers, solvents, additives, etc. Examples of additives include silane coupling agents, crosslinking agents, polymerization initiators, UV absorbers, tackifiers, adhesion promoters, antioxidants, plasticizers, softeners, dyes, pigments, and fillers. Furthermore, additives other than those generally added to pressure-sensitive adhesives or adhesives may also be added.

[0068] Solvent The monomer composition may contain a solvent as needed. In particular, when polymerizing the monomer components by solution polymerization to produce the copolymer of this embodiment, it is preferable to contain a solvent. From the viewpoints of manufacturability and ease of handling, a non-aqueous organic solvent is preferred as such a solvent. Examples of non-aqueous organic solvents include hydrocarbon organic solvents such as hexane, heptane, octane, isooctane, decane, and liquid paraffin; ether organic solvents such as dimethyl ether, diethyl ether, and tetrahydrofuran; ketone organic solvents such as acetone and methyl ethyl ketone; ester organic solvents such as methyl acetate, ethyl acetate, and butyl acetate; alcohol organic solvents such as ethanol and n-propanol; chloride organic solvents such as methylene chloride, chloroform, and carbon tetrachloride; dimethylformamide, diethylformamide, dimethyl sulfoxide, and dioxane. These organic solvents may be used alone or in combination of two or more. The amount of solvent is typically about 100 to 1,000 parts by mass per 100 parts by mass of the monomer components, but is not limited to this range.

[0069] Polymerization Initiator The monomer composition may contain a polymerization initiator, if necessary. Examples of the polymerization initiator include a photopolymerization initiator and a thermal polymerization initiator.

[0070] Examples of the photopolymerization initiator include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,2'-bis(o-chlorophenyl)-4,4',5,5'-tetraphenyl-1,1'-biimidazole, 2,4,6-tris(trichloromethyl)-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-(p-methoxyphenylvinyl)-1,3,5-triazine, diphenyliodonium tetrafluoroborate, diphenyliodonium hexafluorophosphate, 4,4'-di-tert-butyl ... t-butyldiphenyliodonium tetrafluoroborate, 4-diethylaminophenylbenzenediazonium hexafluorophosphate, benzoin, 2-hydroxy-2-methyl-1-phenylpropan-2-one, benzophenone, thioxanthone, 2,4,6-trimethylbenzoyldiphenylacylphosphine oxide (TPO), triphenylbutylborate tetraethylammonium, diphenyl-4-phenylthiophenylsulfonium hexafluorophosphate, 2,2-dimethoxy-1,2-diphenyl photoradical polymerization initiators such as phenylethan-1-one, phenylglyoxylic acid methyl ester, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, 1,2-octanedione, 1-[4-(phenylthio)-2-(o-benzoyloxime)], and bis(η5-2,4-cyclopentadien-1-yl)bis[2,6-difluoro-3-(1H-pyrrol-1-yl)phenyltitanium]; Examples of the photopolymerization initiator include cationic ring-opening photopolymerization initiators such as 2,4,6-tris(trichloromethyl)-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-(p-methoxyphenylvinyl)-1,3,5-triazine, diphenyliodonium tetrafluoroborate, 4,4'-di-tert-butyldiphenyliodonium tetrafluoroborate, 4-diethylaminophenylbenzenediazonium hexafluorophosphate, and diphenyl-4-phenylthiophenylsulfonium hexafluorophosphate. These photopolymerization initiators may be used alone or in combination of two or more.

[0071] Examples of the thermal polymerization initiator include azo-based polymerization initiators such as dimethyl-2,2'-azobis(2-methylpropionate), 2,2'-azobisisobutyronitrile (AIBN), dimethyl 2,2'-azobisisobutyrate, and azobisdimethylvaleronitrile; and peroxide-based polymerization initiators such as benzoyl peroxide, potassium persulfate, and ammonium persulfate. These thermal polymerization initiators may be used alone or in combination of two or more.

[0072] The amount of the polymerization initiator added is preferably 0.01 to 20 parts by mass, more preferably 0.1 to 15 parts by mass, and even more preferably 0.5 to 10 parts by mass, per 100 parts by mass of the monomer components.

[0073] <Other Constituent Elements> The PSA member of the present embodiment may contain components other than the copolymer of the present embodiment described above. Examples of such components include copolymers or monomers other than the copolymer of the present embodiment, crosslinking agents described below, UV absorbers, tackifiers, adhesion promoters, antioxidants, plasticizers, softeners, dyes, pigments, and fillers.

[0074] <Modes of adhesive member> The adhesive member of this embodiment can be shaped according to its intended use. For example, the adhesive member of this embodiment can be in the following modes: (1) A state in which one side is fixed to an object to be attached and the other side is exposed (2) A state in which both sides are covered with a member that can be easily removed from the adhesive member (3) A state in which one side is fixed to an object to be attached and the other side is covered with a member that can be easily removed from the adhesive member (4) A state in which both sides are exposed

[0075] A specific example of the adhesive member is a film. The term "film" conceptually encompasses both sheets and films. When the adhesive member of this embodiment is a film, its thickness is not particularly limited, but can be, for example, 5 μm to 300 μm. Another specific example of the adhesive member is an adhesive layer constituting an adhesive tape or the like. Furthermore, the adhesive member of this embodiment is also intended to be used for the purpose of bonding a surface coating agent such as a paint, such as a so-called undercoat paint, an intermediate paint, or a primer, to a substrate.

[0076] The shapes of the adherends (substrates) fixed by the PSA member of the present embodiment are not particularly limited. Examples of the shape of the substrates include a shape selected from the group consisting of a plate, a sheet, and a rod.

[0077] The material of the substrate to which the pressure-sensitive adhesive member of the present embodiment is fixed is not particularly limited. The pressure-sensitive adhesive member of the present embodiment has strong adhesive properties to substrates made of a variety of materials. In particular, the pressure-sensitive adhesive member of the present embodiment exhibits improved adhesive strength under wet conditions (especially when water is present on the surface (adherend surface) of the substrate) compared to dry conditions for substrates made of the specific materials described above. Examples of such materials include iron and iron alloys. More specifically, pure iron, steel, and cast iron are included. Examples of steel include carbon steels such as SPC (cold-rolled steel plate), SS (general structural rolled steel), S-C (carbon steel for mechanical structures), and SK (carbon tool steel), as well as alloy steels such as stainless steel, high-tensile steel, alloy tool steel, alloy steel for mechanical structures, and cemented carbide steel. Examples of cast iron include spheroidal graphite cast iron, gray cast iron, and malleable cast iron. Among these materials, the pressure-sensitive adhesive of the present embodiment is preferably used on stainless steel (SUS) under wet conditions.

[0078] When the pressure-sensitive adhesive member of the present embodiment is fixed to a substrate whose adhesive strength improves under humid conditions, it may be used under relatively humid conditions, or may be used in a state in which water is attached to the adherend surface of the substrate or the adherend surface of the adhesive member. The method for attaching water to the adherend surface of the substrate or the adhesive member is not particularly limited, and water can be attached by spraying water onto the adherend surface of the substrate or the adhesive member, for example. Alternatively, the substrate or the adhesive member may be placed under high humidity conditions, and condensation may be generated on their surfaces, thereby attaching water to the adherend surface of the substrate or the adhesive member. Condensation may be generated intentionally, or accidental condensation may be used.

[0079] In a substrate whose adhesive strength improves under humid conditions, the amount of water present on the surface of the substrate or the surface of the adhesive member is not particularly limited. However, from the viewpoint of sufficiently improving adhesive strength, the total amount of water present on the surface of the substrate or the surface of the adhesive member is preferably 1 g / m or less. ２It is preferable that the content is 3 g / m or more. ２ More preferably, it is 5 g / m or more. ２ On the other hand, from the viewpoint of the upper limit of the amount of water that can be present on the surface of the substrate or the PSA member, the total amount of water present on the surface of the substrate or the PSA member is preferably 50 g / m or more. ２ Preferably, the weight is 25 g / m or less. ２ More preferably, it is 15 g / m or less. ２ It is even more preferable that:

[0080] Furthermore, the adhesive member of the present embodiment exhibits high adhesive strength under wet or dry conditions even for substrates made of materials other than those whose adhesive strength improves under wet conditions. Examples of substrate materials that can be fixed by the adhesive member of the present embodiment include inorganic materials such as glass, hydroxyapatite, titanium oxide, zinc oxide, iron oxide, indium tin oxide (ITO), and molybdenum-aluminum-molybdenum laminated structure (MAM); metal materials such as aluminum (Al), copper (Cu), gold (Pt), silver (Ag), zinc (Zn), tin (Sn), titanium (Ti), and alloys thereof; and organic materials such as polyvinyl chloride (PVC), polycarbonate (PC), polyethylene terephthalate (PET), polypropylene (PP), polyethylene (PE), acrylonitrile butadiene styrene copolymer resin (ABS), polytetrafluoroethylene (PTFE), polyimide (PI), and fiber-reinforced plastic (FRP).

[0081] As described above, the pressure-sensitive adhesive member of the present embodiment has good adhesive properties for substrates of various materials, and is therefore suitable as a pressure-sensitive adhesive for bonding substrates of different materials. In particular, it is preferable that the material of at least one of the substrates is a material that improves the adhesive strength of the pressure-sensitive adhesive member of the present embodiment under humid conditions. Of course, the pressure-sensitive adhesive of the present embodiment may also be used to bond substrates of the same material. In this case, it is preferable that the material of both substrates is a material that improves the adhesive strength of the pressure-sensitive adhesive member of the present embodiment under humid conditions.

[0082] <Method for manufacturing adhesive member> The method for manufacturing the adhesive member according to the present embodiment is not particularly limited, but the composition containing the copolymer containing the structural unit A and the structural unit B according to the present embodiment (hereinafter simply referred to as "polymer composition") can be applied to the surface of glass, release paper, the object to be adhered (substrate) itself, or the like, and then cured.

[0083] The curing of the polymer composition of the present embodiment may occur in various ways, including (A) a form in which the copolymer of the present embodiment contained in the polymer composition of the present embodiment chemically reacts with a crosslinking agent described below and cures, (B) a form in which the copolymer is turned into a film by removing a solvent or the like contained in the polymer composition of the present embodiment, and (C) a form in which both of these occur.

[0084] <Polymer Composition> The polymer composition of this embodiment is a composition containing the copolymer of this embodiment, which contains the structural unit A and the structural unit B. The polymer composition of this embodiment preferably further contains a crosslinking agent. Furthermore, if necessary, in addition to the copolymer of this embodiment, the polymer composition may contain additives that are generally added to pressure-sensitive adhesives or adhesives, such as copolymers (polymers), monomers, solvents, silane coupling agents, polymerization initiators, UV absorbers, tackifiers, adhesion promoters, antioxidants, plasticizers, softeners, dyes, pigments, and fillers.

[0085] (Copolymer) Since the details of the copolymer in this embodiment have been described above, detailed description will be omitted. In order to obtain high adhesiveness, the proportion of the copolymer in this embodiment in the polymer composition of this embodiment is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 70% by mass or more, and particularly preferably 80% by mass or more, based on the polymer composition.

[0086] (Crosslinking Agent) The crosslinking agent reacts with the functional groups in the copolymer to form a crosslinked structure. The crosslinking agent is not particularly limited as long as it reacts with the functional groups in the copolymer to form a crosslinked structure, and examples thereof include epoxy-based crosslinking agents, isocyanate-based crosslinking agents, aziridine-based crosslinking agents, melamine-based crosslinking agents, aldehyde-based crosslinking agents, amine-based crosslinking agents, and metal chelate-based crosslinking agents. Among these, epoxy-based crosslinking agents are preferred because of their excellent adhesive properties and pot life. These crosslinking agents may be used alone or in combination of two or more.

[0087] Examples of the epoxy crosslinking agent include bisphenol A-epichlorohydrin type epoxy resins, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glycerin diglycidyl ether, glycerin triglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylolpropane triglycidyl ether, sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl erythritol, diglycerol polyglycidyl ether, 1,3'-bis(N,N-diglycidylaminomethyl)cyclohexane, N,N,N',N'-tetraglycidyl-m-xylylenediamine, etc. Among these epoxy crosslinking agents, polyfunctional epoxy resins such as 1,3'-bis(N,N-diglycidylaminomethyl)cyclohexane and N,N,N',N'-tetraglycidyl-m-xylylenediamine are preferred in terms of high reactivity.

[0088] Examples of the isocyanate crosslinking agent include aromatic isocyanate crosslinking agents such as tolylene diisocyanate crosslinking agents such as 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate, xylylene diisocyanate crosslinking agents such as 1,3-xylylene diisocyanate, diphenylmethane crosslinking agents such as diphenylmethane-4,4-diisocyanate, and naphthalene diisocyanate crosslinking agents such as 1,5-naphthalene diisocyanate; isophorone diisocyanate, 1,4-cyclohexane diisocyanate, and the like. Examples of suitable crosslinking agents include alicyclic isocyanate crosslinking agents such as hexamethylene diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, methylcyclohexane diisocyanate, isopropylidenedicyclohexyl-4,4'-diisocyanate, 1,3-diisocyanatomethylcyclohexane, and norbornane diisocyanate; aliphatic isocyanate crosslinking agents such as hexamethylene diisocyanate and trimethylhexamethylene diisocyanate; and adducts, biurets, and isocyanurates of the above-mentioned isocyanate compounds. Among these isocyanate crosslinking agents, tolylene diisocyanate crosslinking agents are preferred in terms of pot life and durability, xylylene diisocyanate crosslinking agents or isocyanurate skeleton-containing isocyanate crosslinking agents are preferred in terms of shortening the aging time, and aromatic ring-free isocyanate crosslinking agents are preferred in terms of yellowing resistance. Among these, specifically, tolylene diisocyanate, xylylene diisocyanate, an adduct of hexamethylene diisocyanate and trimethylolpropane, and a nurate are preferred because they have an excellent balance of durability, pot life, and crosslinking rate.

[0089] Examples of the aziridine crosslinking agent include tetramethylolmethane-tri-β-aziridinylpropionate, trimethylolpropane-tri-β-aziridinylpropionate, N,N'-diphenylmethane-4,4'-bis(1-aziridinecarboxamide), and N,N'-hexamethylene-1,6-bis(1-aziridinecarboxamide).

[0090] Examples of the melamine-based crosslinking agent include hexamethoxymethylmelamine, hexaethoxymethylmelamine, hexapropoxymethylmelamine, hexaptoxymethylmelamine, hexapentyloxymethylmelamine, hexahexyloxymethylmelamine, and melamine resins.

[0091] Examples of the aldehyde crosslinking agent include glyoxal, malondialdehyde, succindialdehyde, maleic dialdehyde, glutaric dialdehyde, formaldehyde, acetaldehyde, and benzaldehyde.

[0092] Examples of the amine-based crosslinking agent include hexamethylenediamine, triethyldiamine, polyethyleneimine, hexamethylenetetraamine, diethylenetriamine, triethyltetraamine, isophoronediamine, amino resins, and polyamides.

[0093] Examples of the metal chelate crosslinking agent include coordination compounds of polyvalent metals such as aluminum, iron, copper, zinc, tin, titanium, nickel, antimony, magnesium, vanadium, chromium, and zirconium with acetylacetone or acetoacetyl ester.

[0094] From the viewpoint of obtaining good adhesion, the content of the crosslinking agent is preferably 0.001 to 20 parts by mass, more preferably 0.01 to 15 parts by mass, even more preferably 0.05 to 10 parts by mass, and particularly preferably 0.09 to 5 parts by mass, relative to 100 parts by mass of the copolymer.

[0095] (Preparation of polymer composition) The polymer composition may be prepared by separating the copolymer obtained from the above-mentioned monomer composition, or may be used as a polymer composition by adding the above-mentioned components to the monomer composition after the polymerization reaction as needed. The method and order of addition of the components are not particularly limited, and various methods can be used, such as a method of adding and mixing the components all at once, or a method of mixing any components and then mixing the remaining components all at once or sequentially.

[0096] The monomer composition of this embodiment can also be used to produce the PSA member of this embodiment. That is, a PSA film can also be produced by applying the monomer composition of this embodiment to the surface of an object to be adhered, copolymerizing the contained monomer α and monomer β on the surface of the object to form the polymer composition of this embodiment, and subsequently curing the polymer composition of this embodiment.

[0097] [Adhesive kit] The adhesive kit of the present embodiment includes the adhesive member of the present embodiment described above and an adhesive enhancer containing water. Since the adhesive member included in the adhesive kit of the present embodiment is the adhesive member of the present embodiment described above, detailed description thereof will be omitted.

[0098] <Adhesion enhancer> The adhesion enhancer is a material containing water. The adhesion enhancer contains water as an essential component, and may contain other components such as a surfactant, a leveling agent, a wetting agent, a hydrophilizing agent, a bactericide, etc. as necessary. In particular, it is preferable to contain a leveling agent, a wetting agent, a hydrophilizing agent, etc. in order to uniformly distribute water on the adherend surface of the substrate or the adhesive member (to wet the surface). These other components may be used as a part of themselves, mixed with water, or separately. In other words, the number of adhesion enhancers in the adhesive kit is not particularly limited.

[0099] The adhesive enhancer may be in the form of a liquid, a gel, or a solid (e.g., a sheet). For example, a gel or sheet adhesive enhancer can be heated to cause water inside the material to exist between the surface of the substrate and the adhesive member.

[0100] The proportion of water in the adhesive enhancer is not particularly limited, but from the viewpoint of fully exerting the adhesive properties of the adhesive material, it is preferably 50% or more, more preferably 65% ​​or more, and even more preferably 80% or more.

[0101] Another embodiment of the adhesive kit is a combination of the polymer composition of the present embodiment and a water-containing adhesive enhancer. As described above, the adhesive kit of this embodiment can be used by directly applying the polymer composition to one substrate to form an adhesive member, and then arranging an adhesive enhancer on one side of the other substrate or the adhesive member.

[0102] The present embodiment will be described in more detail below based on examples, but the present embodiment is not limited to these examples.

[0103] Chemicals and the like used in the present examples are listed below with their abbreviations. <Monomer α> Monomer α1: n-butyl acrylate (trade name: THFA, manufactured by Mitsubishi Chemical Corporation) Monomer α2: acrylic acid (manufactured by Nippon Shokubai Co., Ltd.) <Monomer β> Monomer β1: 2-hydroxy-3-(methacryloyloxy)propyl 3,4-dihydroxybenzoate (DHBA-GMA, trade name: CM03, manufactured by Osaka Organic Chemical Industry Ltd.) <Monomer C> Monomer C1: 4-hydroxybutyl acrylate (trade name: 4-HBA, manufactured by Osaka Organic Chemical Industry Ltd.) <Crosslinking agent> Multifunctional epoxy resin (trade name: TETRAD-C, manufactured by Mitsubishi Gas Chemical Company, Inc.) <Substrate> SUS substrate (trade name: Test Piece Stainless Steel Surface Finish Plate BA (Mirror Finish), manufactured by TP Giken Co., Ltd.) Glass substrate (trade name: Slide Glass, manufactured by Matsunami Glass Industry Co., Ltd.) Aluminum substrate (product name: A1050P, manufactured by Nippon Test Panel Co., Ltd.)

[0104] <Preparation of Copolymer (P-1)> A four-necked round-bottom flask equipped with a reflux condenser, a stirrer, a nitrogen gas inlet, and a thermometer was charged with 87 parts by mass of monomer α1, 8 parts by mass of monomer α2, and 5 parts by mass of monomer β1, and further charged with 74 parts by mass of methyl ethyl ketone, 49 parts by mass of n-propanol, and 0.36 parts by mass of 2,2'-azobisisobutyronitrile (AIBN) as a polymerization initiator. The contents were heated with stirring, and the internal temperature was raised to 60°C to initiate the reaction. The reaction was continued for about 15 hours, yielding composition 1 containing copolymer (P-1).

[0105] [Preparation of Polymer Composition 1] 0.1 parts by mass of an epoxy-based crosslinking agent was blended with 100 parts by mass of the solid content of copolymer (P-1) to prepare polymer composition 1 containing copolymer (P-1).

[0106] [Preparation of Adhesive Film] The polymer compositions 1 and 2 prepared above were applied to a PET film substrate (thickness: 100 μm) so that the thickness of the adhesive layer after drying would be approximately 20 μm, and then dried at 100° C. for 10 minutes. A release-treated PET film (release film: thickness: 50 μm) was then attached to the coated surface to protect the exposed adhesive layer, thereby preparing Adhesive Film 1. Hereinafter, in Adhesive Film 1, the side to which the release film is attached may be referred to as one side, and the PET film side of the substrate may be referred to as the other side.

[0107] <Adhesion Measurement> <Adhesion to Dry Surface> The adhesive film 1 obtained above was cut into a 25 mm x 100 mm test piece. The release film was then peeled off from the adhesive film 1, and the film was placed in an atmosphere of 23°C and 50% relative humidity so that one side was in contact with each evaluation substrate, and a 2 kg rubber roller was rolled back and forth once to adhere the film to the substrate. After leaving the film to stand for 60 minutes in the same atmosphere, the 180° peel strength (N / 25 mm) was measured at a peel speed of 300 mm / min, and the adhesive strength to the dry surface was evaluated. The results are shown in Table 1.

[0108] <Adhesion to wet surface> Purified water was sprayed onto each evaluation substrate using a spray bottle, and 8.7 g / m ２ The adhesive strength to a wet surface was evaluated in the same manner as in measuring the adhesive strength to a dry surface, except that purified water of 1000 ml was present and the standing time was 5 minutes. The results are shown in Table 1.

[0109]

[0110] As shown in Table 1, PSA film 1 exhibits improved adhesive strength under wet conditions compared to dry conditions for substrates made of specific materials. PSA film 1 also exhibits high adhesive strength under both dry and wet conditions for substrates made of other materials.

[0111] The pressure-sensitive adhesive member of the present invention can exhibit sufficient adhesive performance even in water or under wet conditions, and can therefore be suitably used as an adhesive material for various members such as masking films, surface protection films, display labels, and masking tapes.

Claims

1. A pressure-sensitive adhesive member comprising a copolymer having a structural unit A and a structural unit B, wherein the structural unit A is represented by the following formula (I): [In the formula, R １ represents a hydrogen atom or methyl; １ represents a single bond, -O-, -NH-, -NR ６ represents -, -NHC(O)O-, or -NHC(O)NH-; W １ is a single bond, or C １－２０ represents alkylene; ２ is methyl, hydroxyl, optionally substituted C １－６ R represents an alkoxy group, an optionally substituted phenyl group, an optionally substituted phenoxy group, an optionally substituted 5- or 6-membered heteroaryl group, an optionally substituted 3- to 8-membered saturated or partially unsaturated hydrocarbon ring, an optionally substituted 3- to 8-membered saturated or partially unsaturated heterocycle, or (meth)acryloyloxy; ６ is an optionally substituted C １－８ The structural unit B is one or more of the following formula (II): [In the formula, R ３ represents a hydrogen atom or methyl; ２ is a C group in which at least one hydrogen atom is replaced by hydroxyl. １－２０ represents alkylene; ２ represents a single bond, —O—, —CH(OH)—, —C(O)O—, —OC(O)—, or —OC(O)O—; W ３ is a single bond, C １－６ Alkylene, C ２－６ R represents alkenylene; ４ and R ５ each independently represents a hydrogen atom or a hydroxyl; ４ and R ５ and none of the groups are hydrogen atoms.

2. The structural unit A is ２ A structural unit A1 in which R is methyl; ２ The adhesive member according to claim 1 , comprising a structural unit A2, wherein A1 is hydroxyl.

3. The structural unit B is ４ and the R ５ The pressure-sensitive adhesive member according to claim 1 , comprising a structural unit B1 in which is hydroxyl.

4. The adhesive material according to claim 1, wherein the content of the structural unit B is 1% by mass or more and 20% by mass or less.

5. The adhesive member according to claim 1, which is a film.

6. An adhesive kit comprising the adhesive member according to claim 1 or 2 and an adhesive enhancer containing water.

7. A copolymer having a structural unit A and a structural unit B, wherein the structural unit A is represented by the following formula (I): [In the formula, R １ represents a hydrogen atom or methyl; １ represents a single bond, -O-, -NH-, -NR ６ represents -, -NHC(O)O-, or -NHC(O)NH-; W １ is a single bond, or C １－２０ represents alkylene; ２ is methyl, hydroxyl, optionally substituted C １－６ R represents an alkoxy group, an optionally substituted phenyl group, an optionally substituted phenoxy group, an optionally substituted 5- or 6-membered heteroaryl group, an optionally substituted 3- to 8-membered saturated or partially unsaturated hydrocarbon ring, an optionally substituted 3- to 8-membered saturated or partially unsaturated heterocycle, or (meth)acryloyloxy; ６ is an optionally substituted C １－８ The structural unit B is one or more of the following formula (II): [In the formula, R ３ represents a hydrogen atom or methyl; ２ is a C group in which at least one hydrogen atom is replaced by hydroxyl. １－２０ represents alkylene; ２ represents a single bond, —O—, —CH(OH)—, —C(O)O—, —OC(O)—, or —OC(O)O—; W ３ is a single bond, C １－６ Alkylene, C ２－６ R represents alkenylene; ４ and R ５ each independently represents a hydrogen atom or a hydroxyl; ４ and R ５ and none of the structural units A is a hydrogen atom, ２ A structural unit A1 in which R is methyl; ２ and a structural unit A2, wherein A1 is hydroxyl.

8. A composition comprising the copolymer of claim 7.

9. A composition comprising a monomer α and a monomer β, wherein the monomer α is represented by the following formula (I'): [In the formula, R １ represents a hydrogen atom or methyl; １ represents a single bond, -O-, -NH-, -NR ６ represents -, -NHC(O)O-, or -NHC(O)NH-; W １ is a single bond, or C １－２０ represents alkylene; ２ is methyl, hydroxyl, optionally substituted C １－６ R represents an alkoxy group, an optionally substituted phenyl group, an optionally substituted phenoxy group, an optionally substituted 5- or 6-membered heteroaryl group, an optionally substituted 3- to 8-membered saturated or partially unsaturated hydrocarbon ring, an optionally substituted 3- to 8-membered saturated or partially unsaturated heterocycle, or (meth)acryloyloxy; ６ is an optionally substituted C １－８ and the monomer β is one or more of the following formula (II′): [In the formula, R ３ represents a hydrogen atom or methyl; ２ is a C group in which at least one hydrogen atom is replaced by hydroxyl. １－２０ represents alkylene; ２ represents a single bond, —O—, —CH(OH)—, —C(O)O—, —OC(O)—, or —OC(O)O—; W ３ is a single bond, C １－６ Alkylene, C ２－６ R represents alkenylene; ４ and R ５ each independently represents a hydrogen atom or a hydroxyl; ４ and R ５ and none of the groups are hydrogen atoms.

10. The monomer α is ２ is methyl; and ２ and monomer A2', wherein A2' is hydroxyl.

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