JP2020045381A - Adhesive tape and manufacturing method of semiconductor device using the same - Google Patents

Abstract

To provide an adhesive tape having high adhesive force before radiation curing, easily being detached from an adherend after radiation curing, and less in stains of a transfer contaminant or an adherend surface derived from an adhesion.SOLUTION: There is provided an adhesive tape having a substrate film and an adhesive layer, in which the adhesive layer contains a (meth)acrylic copolymer (A) containing a structural unit selected from N,N-dialkyl (meth)acrylamide, N-(meth)acryloylmorpholine, N-alkoxy alkylacrylamide or the like, and a structural unit having a crosslinking functional group, and having weight average molecular weight of 20 to 2,000,000, and molecular distribution of 2.5 or less, a crosslinking agent (B), and a compound (C) selected from an anti-rust agent a primary antioxidant, is formed from an irradiation curing adhesive composition having content of a radiation polymerizable group in a solid component of 0.1 to 10 mmol/g.SELECTED DRAWING: None

Description

  The present invention relates to a pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer formed from a radiation-curable pressure-sensitive adhesive composition, and a method for manufacturing a semiconductor device using the same.

  In the manufacture of semiconductor devices, after a circuit pattern is formed on the front surface of a semiconductor wafer, a back grinding process for thinly grinding the back surface of the semiconductor wafer after forming the circuit pattern, the back surface of the semiconductor wafer finished to a predetermined thickness has elasticity. A dicing step of cutting the semiconductor wafer into individual chip sizes after bonding the adhesive tape, an expanding step of expanding the adhesive tape to divide the chips, and a pickup step of picking up the divided semiconductor wafers (semiconductor chips) are performed. After being picked up, the semiconductor chip is packaged by resin sealing.

  In the back grinding step and the dicing step, a radiation-curable pressure-sensitive adhesive tape is used. Specifically, in the back grinding step, a radiation-curable pressure-sensitive adhesive tape (back grinding tape) is attached to protect the circuit pattern surface during grinding. When peeling the back grind tape, the back grind tape is irradiated with radiation to cure the adhesive layer of the back grind tape, reduce the adhesive strength, and peel the back grind tape.

  In the dicing step, a radiation-curable adhesive tape (dicing tape) is used to fix the divided semiconductor chips. After the dicing step, the chip is divided, and the dicing tape is irradiated with radiation to cure the adhesive layer of the dicing tape and reduce the adhesive strength. Next, the cut wafer is pushed up from the tape substrate side with a needle, and the cut wafer is detached or separated from the dicing tape, separated as a semiconductor chip, and picked up.

  As a radiation-curable pressure-sensitive adhesive tape that can be used as a semiconductor processing tape such as a back grinding tape and a dicing tape, for example, a pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer formed from a radiation-curable (meth) acrylic pressure-sensitive adhesive composition (See Patent Literature 1 (Examples 3, 5, and 6) and Patent Literature 2 (Example 1)) are known.

  By the way, in a conventional method of manufacturing a semiconductor device used for an electronic / electric device, a semiconductor chip mounted on a substrate is conductively connected by wire bonding. However, in response to recent demands for further downsizing, thinning, and weight reduction of devices, similar requests have been made for electronic components such as semiconductor devices used inside these devices. As one approach to miniaturization and high-density mounting of electronic components, for example, a three-dimensional mounting technique for realizing high-density mounting by stacking semiconductor chips has been proposed (see Patent Document 3 (paragraph 0076)). . For example, a semiconductor package structure in which a through electrode is formed inside a semiconductor chip and stacked on a mounting chip called an interposer (see Patent Document 4 (paragraphs 0043 to 0045)) has been proposed. Metal such as copper is used as a conductor for the through electrode.

  During the dicing process of the semiconductor wafer on which such a through electrode is formed, the back surface of the wafer and the electrode on the back surface of the wafer must be sufficiently held. For this reason, radiation-curable adhesive tapes used in the manufacture of semiconductor devices have a large adhesive force before irradiation, and when peeled off after irradiation, they come from fragile semiconductor wafers with fine processing or thin thin films formed on the surface. Even so, it is required that the adhesive strength is sufficiently reduced so that the adhesive can be easily peeled off.

  Here, in the conventional radiation-curable pressure-sensitive adhesive tape, the adhesive force when peeling off from the semiconductor wafer is not sufficiently reduced even when irradiated with radiation, and adhesive residue is likely to be generated. Therefore, for example, in Patent Document 5, radiation-curable polymerizable groups are introduced into the side chains of a (meth) acrylic copolymer having a molecular weight distribution of 1.05 to 2.5 to thereby improve the radiation of the pressure-sensitive adhesive layer. It is disclosed that curability can be enhanced, adhesive force can be sufficiently reduced, and adhesive residue can be reduced.

JP-A-60-223139 JP-A-5-32946 JP-A-2002-50738 JP 2005-236245 A JP-A-2005-124300

  In the pressure-sensitive adhesive tape proposed in Patent Document 5, it has been studied to sufficiently reduce the pressure-sensitive adhesive strength by radiation curing. However, Patent Document 5 does not discuss a method for improving the adhesive strength before radiation curing.

  Further, as described above, a semiconductor processing tape such as a back grinding tape and a dicing tape is used by being attached to a circuit surface and an electrode surface. For this reason, there is a concern about defective transfer and the like due to transfer contaminants (adhesive residue and the like) derived from the adhesive after the tape is peeled off. When the pressure-sensitive adhesive tape proposed in Patent Document 5 is used, a large-scale (several μm to several tens μm) residue that can be observed with an optical microscope or visually can be reduced, but a fine residue that cannot be visually confirmed. There is a problem in that fine stains on the surface of the adherend, which are considered to be caused by an object or an adhesive tape, cannot be reduced.

  The present invention has been made in view of the above circumstances, it is difficult to peel off before radiation curing, can exhibit high adhesive strength, and can be easily peeled from the adherend after radiation curing, transfer from an adhesive An object of the present invention is to provide an adhesive tape that can reduce contaminants.

  The pressure-sensitive adhesive tape of the present invention that can solve the above-mentioned problem has a base film, and a pressure-sensitive adhesive layer formed on at least one surface of the base film, wherein the pressure-sensitive adhesive layer is (meth) It is formed from a radiation-curable pressure-sensitive adhesive composition containing an acrylic copolymer (A), a crosslinking agent (B) and a compound (C), and the (meth) acrylic copolymer (A) is The (meth) acrylic copolymer (A), which contains a structural unit (a-1) represented by the following general formula (1) and a structural unit (a-2) having a crosslinkable functional group, and Has a weight average molecular weight of 200,000 to 2,000,000 and a molecular weight distribution (PDI) of 2.5 or less, and the compound (C) is at least one compound selected from the group consisting of a rust inhibitor and a primary antioxidant And the solid content of the radiation-curable pressure-sensitive adhesive composition And the content of the radiation-polymerizable group is 0.1mmol / g~10mmol / g.

［式（１）において、Ｒ¹¹は水素原子または置換基を有していてもよい鎖状もしくは環状の炭化水素基を示す。Ｒ¹²は置換基を有していてもよい鎖状もしくは環状の炭化水素基を示す。Ｒ¹¹およびＲ¹²が互いに結合して環状構造を形成していてもよい。Ｒ¹³は水素原子またはメチル基を示す。］

[In the formula (1), R ¹¹ represents a hydrogen atom or a linear or cyclic hydrocarbon group which may have a substituent. R ¹² represents a chain or cyclic hydrocarbon group which may have a substituent. R ¹¹ and R ¹² may combine with each other to form a cyclic structure. R ¹³ represents a hydrogen atom or a methyl group. ]

  In the pressure-sensitive adhesive tape of the present invention, the (meth) acrylic copolymer (A) as a main raw material of the pressure-sensitive adhesive layer has the structural unit (a-1) represented by the general formula (1), and has a predetermined weight. Since the radiation-curable pressure-sensitive adhesive composition having the average molecular weight and the molecular weight distribution and forming the pressure-sensitive adhesive layer contains the compound (C), the adherend, particularly the adherend having a metal surface Demonstrates high adhesion to In addition, since the content of the radiation-polymerizable group in the solid content of the radiation-curable pressure-sensitive adhesive composition is adjusted to a predetermined amount, by irradiating radiation, it is possible to sufficiently reduce the adhesive force of the pressure-sensitive adhesive layer. Can be. In addition, transfer contaminants derived from the adhesive on the adherend after irradiation with radiation can be reduced.

  The pressure-sensitive adhesive tape of the present invention has high adhesive strength before radiation curing, can be easily peeled from the adherend after radiation curing, and generates transfer contaminants derived from the adhesive and stains on the surface of the adherend. Less is.

<Adhesive tape>
The pressure-sensitive adhesive tape of the present invention is formed from a radiation-curable pressure-sensitive adhesive composition (hereinafter sometimes simply referred to as “pressure-sensitive adhesive composition”) on at least one surface of the substrate film and the substrate film. It is a pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer. The pressure-sensitive adhesive layer is formed on at least one side or at least a part of the base film. The pressure-sensitive adhesive layer may have a single-layer structure or a multilayer structure.

  In general, "sheet" refers to a flat product that is thin in definition according to JIS and generally has a small thickness compared to its length and width. Generally, "film" refers to a product that is thinner than its length and width. A thin, flat product whose thickness is extremely small and whose maximum thickness is arbitrarily limited is usually supplied in the form of a roll (Japanese Industrial Standard JIS K6900). For example, in terms of thickness, a sheet having a thickness of 100 μm or more may be referred to as a sheet in a narrow sense, and a film having a thickness of less than 100 μm may be referred to as a film. However, the boundary between the sheet and the film is not clear, and in the present invention, it is not necessary to distinguish between the two in the wording. Therefore, in the present invention, the term "sheet" includes the "film" even when the term "sheet" is used. However, it is assumed that "sheet" is included.

  The pressure-sensitive adhesive tape of the present invention has high adhesive strength before radiation curing, can be easily peeled from the adherend after radiation curing, and generates transfer contaminants derived from the adhesive and stains on the surface of the adherend. Less is. Particularly, it has excellent characteristics with respect to an adherend having a metal surface. Examples of the metal include copper and copper alloy. Therefore, the pressure-sensitive adhesive tape of the present invention can be suitably used as a semiconductor processing tape such as a back grinding tape and a dicing tape used by being attached to a circuit surface and an electrode surface, and is preferably used as a dicing tape. Can be. Examples of the semiconductor include silicon, silicon carbide, gallium arsenide (gallium arsenide), gallium phosphide, indium phosphide, and gallium nitride.

  The components constituting the pressure-sensitive adhesive tape of the present invention will be described below.

(1. Adhesive composition)
The pressure-sensitive adhesive composition comprises a (meth) acrylic copolymer (A) (hereinafter sometimes simply referred to as “copolymer (A)”), a crosslinking agent (B), and a compound (C). And The copolymer (A) contains a structural unit (a-1) represented by the general formula (1) and a structural unit (a-2) having a crosslinkable functional group, and has a weight average molecular weight of 20. 10,000 to 2,000,000, and a molecular weight distribution (PDI) of 2.5 or less. The compound (C) contains at least one compound selected from the group consisting of a rust inhibitor and a primary antioxidant. Further, the content of the radiation polymerizable group in the solid content of the pressure-sensitive adhesive composition is 0.1 mmol / g to 10 mmol / g.

  The pressure-sensitive adhesive composition is prepared by coating the composition on a base film and reacting a crosslinkable functional group of the copolymer (A) with a functional group of the crosslinker (B). Layers can be formed. Further, the pressure-sensitive adhesive composition has a radiation-polymerizable group in a solid content (for example, a copolymer (A), a radiation-polymerizable compound (D) described later). Therefore, by irradiating the formed pressure-sensitive adhesive layer with radiation, the pressure-sensitive adhesive layer can be cured and the adhesive strength can be reduced. In the present invention, “radiation” includes, for example, ionizing radiation, that is, X-rays, ultraviolet rays, electron beams, and the like.

  In the present invention, “radiation-polymerizable compound” refers to a compound having a functional group that can be polymerized by irradiation with radiation, and a functional group that can be polymerized by irradiation with radiation is referred to as “radiation-polymerizable group”. Examples of the radiation-polymerizable group include a (meth) acrylolyl group, a vinyl group, and a carbon-carbon double bond. Polymerization of the radiation-polymerizable compound means an addition reaction of the carbon-carbon double bond in the functional group. I do. That is, the “radiation-polymerizable group” means a functional group having an ethylenically unsaturated bond.

  The content of the radiation polymerizable group in the solid content of the pressure-sensitive adhesive composition is preferably 0.1 mmol / g or more, more preferably 0.2 mmol / g or more, and still more preferably 0.5 mmol / g or more. , Preferably at most 10 mmol / g, more preferably at most 5 mmol / g, even more preferably at most 2 mmol / g. When the content of the radiation-polymerizable group is within the above range, by irradiating the radiation, the adhesive force of the adhesive layer is sufficiently reduced, and the adhesive tape can be easily peeled. The content of the radiation-polymerizable group in the solid content can be determined by the amount of the compound or the polymerization raw material used.

  The content of the radiation-polymerizable group is the sum of the radiation-polymerizable groups contained in a solid content (a component excluding a solvent) of the pressure-sensitive adhesive composition, and is a radiation-polymerizable ratio per unit g of the pressure-sensitive adhesive composition. It is the total number of moles of the group. For example, as a method of introducing a radiation-polymerizable group into the pressure-sensitive adhesive composition, a method of introducing a radiation-polymerizable group into a main chain or a side chain of the copolymer (A), a method of introducing a radiation-polymerizable group described later into the pressure-sensitive adhesive composition A method of compounding the compound (D) is exemplified. The radiation polymerizable group introduced into the pressure-sensitive adhesive composition serves as a crosslinking point when the pressure-sensitive adhesive layer is cured.

(1-1. (Meth) acrylic copolymer (A))
The copolymer (A) has a weight average molecular weight of 200,000 to 2,000,000 and a molecular weight distribution (PDI) of 2.5 or less, and is crosslinked with the structural unit (a-1) represented by the general formula (1). And a structural unit (a-2) having a functional functional group.

  The (meth) acrylic copolymer may be any copolymer having a structural unit derived from a (meth) acrylic monomer as a main component (50% by mass or more), and may be a vinyl monomer other than the (meth) acrylic monomer. It can contain structural units derived from it. The content of the structural unit derived from the (meth) acrylic monomer in the copolymer (A) is preferably 80% by mass or more, and more preferably 90% by mass or more in the whole copolymer. In addition, the said copolymer (A) may be comprised only from the structural unit derived from a (meth) acrylic monomer.

  In the present invention, “(meth) acryl” refers to “at least one of acryl and methacryl”. “(Meth) acrylic monomer” refers to a monomer having a “(meth) acryloyl group” in the molecule. “(Meth) acryloyl” refers to “at least one of acryloyl and methacryloyl”. “Vinyl monomer” refers to a monomer having a radically polymerizable carbon-carbon double bond in the molecule. “Structural unit derived from (meth) acrylic monomer” refers to a structural unit in which a radically polymerizable carbon-carbon double bond of a (meth) acrylic monomer is polymerized into a carbon-carbon single bond. The “structural unit derived from a vinyl monomer” refers to a structural unit in which a radically polymerizable carbon-carbon double bond of a vinyl monomer is polymerized into a carbon-carbon single bond.

  The copolymer (A) may be any of a random copolymer, a block copolymer, and a graft copolymer, and is preferably a random copolymer. The copolymer (A) may have a radiation-polymerizable group introduced therein. Examples of the method for introducing a radiation-polymerizable group into the copolymer (A) include a method using a diene as a monomer constituting the structural unit (a-3), and a method in which a radiation-polymerizable group is added to a previously polymerized copolymer. And a method of grafting a compound having the same. Further, the copolymer (A) preferably has no radiation-polymerizable group. By not having a radiation-polymerizable group, a desired adhesive strength is easily obtained.

  The weight average molecular weight (Mw) of the copolymer (A) is 200,000 or more, preferably 400,000 or more, more preferably 500,000 or more, further preferably 600,000 or more, and 2,000,000 or less, preferably 1,800,000. Or less, more preferably 1.5 million or less, still more preferably 1.3 million or less. When the Mw of the copolymer (A) is less than 200,000, the cohesive force is insufficient, heat resistance may be reduced, and the surface of the adherend may be contaminated. May deteriorate. The method for measuring the weight average molecular weight (Mw) will be described later.

  The molecular weight distribution (PDI) of the copolymer (A) is 2.5 or less, preferably 2.3 or less, and more preferably 2.1 or less. The smaller the PDI, the narrower the width of the molecular weight distribution becomes, and the copolymer becomes uniform in molecular weight. When the value is 1.0, the width of the molecular weight distribution is the narrowest. That is, the lower limit of PDI is 1.0. If the PDI is 2.5 or less, the content of low molecular weight or high molecular weight products is low compared to the molecular weight of the designed copolymer, and when used in an adhesive composition, transfer contaminants (paste) Adhesive tape with few residuals) can be obtained. In the present invention, the molecular weight distribution (PDI) is a value calculated by (weight average molecular weight (Mw)) / (number average molecular weight (Mn)), and a method for measuring Mw and Mn will be described later.

  The glass transition temperature (Tg) of the copolymer (A) is preferably -80C or more, more preferably -70C or more, preferably 20C or less, more preferably 0C or less. If the glass transition temperature is -80 ° C or higher, a sufficient cohesive force is imparted to the pressure-sensitive adhesive composition, and the durability of the pressure-sensitive adhesive layer is improved. As a result, peeling is suppressed, and durability is improved.

  The glass transition temperature (Tg) of the copolymer (A) is a value calculated by the following FOX formula (formula (1)). In the formula (1), Tg indicates a glass transition temperature (° C.) of the copolymer. Tgi indicates a glass transition temperature (° C.) when the vinyl monomer i forms a homopolymer. Wi indicates the mass ratio of vinyl monomer i to all vinyl monomers forming the copolymer, and ΔWi = 1. i is a natural number of 1 to n.

  Table 1 shows the glass transition temperatures of typical homopolymers.

(1-1-1. Structural unit (a-1))
The structural unit (a-1) represented by the general formula (1) may be only one type, or may have two or more types. By having the structural unit (a-1), when the copolymer (A) and the compound (C) are used in the pressure-sensitive adhesive composition, although the reason is not clear, the pressure-sensitive adhesive is further increased. Transfer contaminants from the source can be reduced.

［式（１）において、Ｒ¹¹は水素原子、または置換基を有していてもよい鎖状もしくは環状の炭化水素基を示す。Ｒ¹²は置換基を有していてもよい鎖状もしくは環状の炭化水素基を示す。Ｒ¹¹およびＲ¹²が互いに結合して環状構造を形成していてもよい。Ｒ¹³は水素原子またはメチル基を示す。］

[In the formula (1), R ¹¹ represents a hydrogen atom or a linear or cyclic hydrocarbon group which may have a substituent. R ¹² represents a chain or cyclic hydrocarbon group which may have a substituent. R ¹¹ and R ¹² may combine with each other to form a cyclic structure. R ¹³ represents a hydrogen atom or a methyl group. ]

Examples of the chain hydrocarbon group represented by R ^11, may be mentioned linear alkyl group, branched-chain alkyl group. The linear alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and still more preferably 1 to 5 carbon atoms. Examples of the linear alkyl group include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-hexyl group, an n-octyl group, an n-nonyl group, an n-decyl group and an n-lauryl group. Is mentioned. The branched alkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 10 carbon atoms, and still more preferably 3 to 5 carbon atoms. Examples of the branched alkyl group include an isopropyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a 2-ethylhexyl group, a neopentyl group, and an isooctyl group.

Examples of the substituent of the chain hydrocarbon group represented by R ¹¹ include a halogen group, an alkoxy group, a benzoyl group (—COC ₆ H ₅ ), and the like.

The cyclic hydrocarbon group represented by R ^11, cyclic alkyl group, an aromatic group, and the like, cyclic alkyl groups or the aromatic group may have a chain portion. The cyclic alkyl group preferably has 4 to 18 carbon atoms, more preferably has 6 to 12 carbon atoms, and still more preferably has 6 to 10 carbon atoms. Examples of the cyclic alkyl group include a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, and the like. The aromatic group preferably has 6 to 18 carbon atoms, more preferably has 6 to 12 carbon atoms, and still more preferably has 6 to 8 carbon atoms. Examples of the aromatic group include a phenyl group, a tolyl group, a xylyl group, and a mesityl group. Examples of the cyclic alkyl group having a chain portion and the chain portion of the aromatic group having a chain portion include an alkylene group having 1 to 12 carbon atoms, preferably an alkylene group having 1 to 6 carbon atoms, and more preferably Alkylene groups of the formulas 1 to 3 are mentioned.

The substituent having a hydrocarbon group of cyclic represented by R ^11, a halogen group, an alkoxy group, a chain alkyl group, and the like.

Examples of the chain hydrocarbon group represented by R ¹² include a linear alkyl group and a branched alkyl group. The linear alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and still more preferably 1 to 5 carbon atoms. Examples of the linear alkyl group include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-hexyl group, an n-octyl group, an n-nonyl group, an n-decyl group and an n-lauryl group. Is mentioned. The branched alkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 10 carbon atoms, and still more preferably 3 to 5 carbon atoms. Examples of the branched alkyl group include an isopropyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a 2-ethylhexyl group, a neopentyl group, and an isooctyl group.

Examples of the substituent of the chain hydrocarbon group represented by R ¹² include a halogen group, an alkoxy group, and a benzoyl group (—COC ₆ H ₅ ).

Examples of the cyclic hydrocarbon group represented by R ¹² include a cyclic alkyl group and an aromatic group, and the cyclic alkyl group and the aromatic group may have a chain portion. The cyclic alkyl group preferably has 4 to 18 carbon atoms, more preferably has 6 to 12 carbon atoms, and still more preferably has 6 to 10 carbon atoms. Examples of the cyclic alkyl group include a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, and the like. Examples of the aromatic group include a phenyl group, a tolyl group, a xylyl group, and a mesityl group. The aromatic group preferably has 6 to 18 carbon atoms, more preferably has 6 to 12 carbon atoms, and still more preferably has 6 to 8 carbon atoms. Examples of the cyclic alkyl group having a chain portion and the chain portion of the aromatic group having a chain portion include an alkylene group having 1 to 12 carbon atoms, preferably an alkylene group having 1 to 6 carbon atoms, and more preferably Alkylene groups of the formulas 1 to 3 are mentioned.

Examples of the substituent of the cyclic hydrocarbon group represented by R ¹² include a halogen group, an alkoxy group, and a chain alkyl group.

Particularly preferred examples of the group represented by R ¹¹ or R ¹² include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a cyclohexyl group, a phenyl group, and a benzyl group (—CH ₂ C ₆ H ₅ ). Can be mentioned.

Examples of the cyclic structure formed by combining R ¹¹ and R ¹² with each other include a 5- to 7-membered nitrogen-containing heterocyclic ring or a condensed ring formed by condensing two of them. The nitrogen-containing hetero ring preferably has no aromaticity, and is more preferably a saturated ring. Specific examples include structures represented by the following formulas (1-1), (1-2), and (1-3).

［一般式（１−１）、（１−２）、（１−３）において、Ｒ¹⁴は、炭素数１〜６のアルキル基を示す。ｌは０〜５の整数を表す。ｍは０〜４の整数を表す。ｎは０〜４の整数を表す。＊は結合手を表す。ｌが２〜５、ｍが２〜４、ｎが２〜４の場合、複数存在するＲ¹⁴は、それぞれ同一でも異なっていてもよい。］

[In the general formulas (1-1), (1-2) and (1-3), R ¹⁴ represents an alkyl group having 1 to 6 carbon atoms. l represents an integer of 0 to 5. m represents an integer of 0 to 4. n represents the integer of 0-4. * Represents a bond. When 1 is 2 to 5, m is 2 to 4, and n is 2 to 4, a plurality of R ¹⁴ may be the same or different. ]

  Specific examples of the vinyl monomer forming the structural unit represented by the general formula (1) include N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, and N, N-diisopropyl (meth). Dialkyl (meth) acrylamides such as acrylamide; cyclic amides such as N- (meth) acrylylmorpholine; and alkoxyalkylacrylamides such as N-methoxymethylacrylamide and N-ethoxymethylacrylamide. Among them, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide and acryloylmorpholine are preferred.

  The content of the structural unit (a-1) is preferably 5% by mass or more, more preferably 10% by mass or more, even more preferably 15% by mass or more, and 40% by mass or less based on 100% by mass of the whole copolymer. Is preferably 35% by mass or less, more preferably 30% by mass or less. When the content of the structural unit (a-1) is 5% by mass or more, the adhesive force with the adherend can be improved. When the content is 40% by mass or less, the wettability with the adherend becomes good, The adhesive strength is improved.

(1-1-2. Structural unit (a-2))
The structural unit (a-2) having a crosslinkable functional group may be only one type, or may have two or more types.

  The crosslinkable functional group is a functional group that can react with a reactive group of the crosslinking agent (B) described below. Examples of the crosslinkable functional group include one or more selected from the group consisting of a hydroxy group, a carboxy group, a sulfonic acid group, a phosphoric acid group, a phosphonic acid group, a phosphinic acid group, and an epoxy group. A hydroxy group and / or a carboxy group.

  The content of the crosslinkable functional group in the copolymer (A) is preferably at least 0.005 mmol / g, more preferably at least 0.05 mmol / g, further preferably at least 0.1 mmol / g, particularly preferably at least 0. 0.1 mmol / g or less, preferably 1.5 mmol / g or less, more preferably 1.0 mmol / g or less, further preferably 0.7 mmol / g or less, and particularly preferably 0.5 mmol / g or less. When the content of the crosslinkable functional group is 0.005 mmol / g or more, the durability of the pressure-sensitive adhesive composition before irradiation is excellent, and when the content is 1.5 mmol / g or less, the pressure-sensitive adhesive composition before irradiation is not irradiated to the adherend. Excellent adhesion. The content of the crosslinkable functional group is the sum of all the crosslinkable functional groups of the copolymer (A), and is the total number of moles of the crosslinkable functional group per unit g of the copolymer (A). .

  The crosslinkable functional group may be present in any of a structural unit derived from a (meth) acrylic monomer and a structural unit derived from a vinyl monomer other than the (meth) acrylic monomer. The monomer forming the structural unit is a (meth) acrylic monomer having a crosslinkable functional group and a vinyl monomer other than the (meth) acrylic monomer having a crosslinkable functional group.

  The (meth) acrylic monomer having a crosslinkable functional group includes a (meth) acrylic monomer having a hydroxy group, a (meth) acrylic monomer having a carboxy group, a (meth) acrylic monomer having a sulfonic acid group, and a phosphoric acid group (Meth) acrylic monomers, (meth) acrylic monomers having an epoxy group, and the like can be given. Examples of the vinyl monomer other than the (meth) acrylic monomer having a crosslinkable functional group include a vinyl monomer having a hydroxy group, a vinyl monomer having a carboxy group, and a vinyl monomer having an epoxy group. Among these, a (meth) acrylic monomer having a hydroxy group and a (meth) acrylic monomer having a carboxy group are preferred.

  Examples of the (meth) acrylic monomer having a hydroxy group include 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and 6 Hydroxyalkyl (meth) acrylates such as -hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate and 12-hydroxylauryl (meth) acrylate; (4-hydroxymethylcyclohexyl) Hydroxyalkylcycloalkyl (meth) acrylates such as methyl (meth) acrylate; and caprolactone adducts of hydroxyalkyl (meth) acrylate; Among these, hydroxyalkyl (meth) acrylate is preferable, and (meth) acrylate having a hydroxyalkyl group having 1 to 5 carbon atoms is more preferable.

  Examples of the (meth) acrylic monomer having a carboxy group include carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, 2- (meth) acryloyloxyethyl succinate, 2- (meth) acryloyloxyethyl maleate, A monomer obtained by reacting an acid anhydride such as maleic anhydride, succinic anhydride, or phthalic anhydride with a (meth) acrylate having a hydroxy group such as-(meth) acryloyloxyethyl phthalate; and (meth) acrylic acid. . Among these, (meth) acrylic acid is preferred.

  Examples of the (meth) acrylic monomer having a sulfonic acid group include ethyl sulfonic acid (meth) acrylate.

  Examples of the (meth) acrylic monomer having a phosphate group include 2- (phosphonooxy) ethyl (meth) acrylate and the like.

  Examples of the (meth) acrylic monomer having an epoxy group include glycidyl (meth) acrylate and 3,4-epoxycyclohexylmethyl (meth) acrylate.

  Examples of the vinyl monomer having a hydroxy group include p-hydroxystyrene and allyl alcohol.

  Examples of the vinyl monomer having a carboxy group include crotonic acid, maleic acid, itaconic acid, citraconic acid, and cinnamic acid.

  Examples of the vinyl monomer having an epoxy group include 2-allyloxirane, glycidylvinylether, and 3,4-epoxycyclohexylvinylether.

  The content of the structural unit (a-2) is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, even more preferably 1.0% by mass or more based on 100% by mass of the whole copolymer. The content is preferably 10% by mass or less, more preferably 8% by mass or less, and further preferably 6% by mass or less. When the content of the structural unit (a-2) is 0.1% by mass or more, the cohesive failure of the pressure-sensitive adhesive is suppressed, and when the content is 10% by mass or less, wettability with an adherend is improved, and the adhesive force is reduced. improves.

(1-1-3. Structural unit (a-3))
The copolymer (A) may have another structural unit (a-3) in addition to the structural unit (a-1) and the structural unit (a-2). The structural unit (a-3) is not particularly limited as long as it is formed of a vinyl monomer copolymerizable with both the structural unit (a-1) and the monomer forming the structural unit (a-2). Only one type may be used, or two or more types may be provided.

  Examples of the vinyl monomer capable of forming the structural unit (a-3) include a (meth) acrylate having a linear alkyl group, a (meth) acrylate having a branched alkyl group, a (meth) acrylate having a cyclic alkyl group, (Meth) acrylate having a polycyclic structure, (meth) acrylate having an aromatic group, (meth) acrylate having a polyalkylene glycol structural unit, (meth) acrylate having an alkoxy group, and having an oxygen-containing heterocyclic group ( (Meth) acrylate monomers such as (meth) acrylates and (meth) acrylates having a tertiary amino group; aromatic vinyl monomers, vinyl monomers having a heterocycle, vinylamide, vinyl carboxylate, and vinyl monomers having a tertiary amino group; Vinyl monomer having a quaternary ammonium base, α-ole Fin, such as dienes (meth) other than the acrylic monomer vinyl monomer; and the like. Among these, a group consisting of a (meth) acrylate having a linear alkyl group, a (meth) acrylate having a branched alkyl group, a (meth) acrylate having a cyclic alkyl group, and a (meth) acrylate having an aromatic group. At least one selected from

  As the (meth) acrylate having a straight-chain alkyl group, a (meth) acrylate having a straight-chain alkyl group having 1 to 20 carbon atoms in a straight-chain alkyl group is preferable. A (meth) acrylate having a linear alkyl group having 1 to 10 is more preferable. Specific examples of the (meth) acrylate having a linear alkyl group include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, and n-hexyl ( (Meth) acrylate, n-octyl (meth) acrylate, n-nonyl (meth) acrylate, decyl (meth) acrylate, n-lauryl (meth) acrylate, n-stearyl (meth) acrylate, and the like.

  As the (meth) acrylate having a branched alkyl group, a (meth) acrylate having a branched alkyl group having 3 to 20 carbon atoms in the branched alkyl group is preferable. (Meth) acrylates having 3 to 10 branched alkyl groups are preferred. Specific examples of the (meth) acrylate having a branched alkyl group include isopropyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, and isooctyl (meth) acrylate. , 2-ethylhexyl (meth) acrylate, isononyl (meth) acrylate, isodecyl (meth) acrylate, and the like.

  The (meth) acrylate having a cyclic alkyl group is preferably a (meth) acrylate having a cyclic alkyl group having 6 to 12 carbon atoms. Examples of the cyclic alkyl group include a cyclic alkyl group having a single ring structure (for example, a cycloalkyl group), and may have a chain portion. Specific examples of (meth) acrylates having a monocyclic cyclic alkyl group include cyclohexyl (meth) acrylate, methylcyclohexyl (meth) acrylate, and cyclododecyl (meth) acrylate.

  The (meth) acrylate having a polycyclic structure is preferably a (meth) acrylate having a polycyclic structure having 6 to 12 carbon atoms. Examples of the polycyclic structure include a cyclic alkyl group having a bridged ring structure (for example, an adamantyl group, a norbornyl group, and an isobornyl group), and may have a chain portion. Specific examples of the (meth) acrylate having a polycyclic structure include isobornyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, dicyclopentanyloxyethyl (meth) acrylate, and 2-methyl-2-adamantyl. (Meth) acrylate, 2-ethyl-2-adamantyl (meth) acrylate, and the like.

  The (meth) acrylate having an aromatic group is preferably a (meth) acrylate having an aromatic group having 6 to 12 carbon atoms. Examples of the aromatic group include an aryl group and the like, and may have a chain portion such as an alkylaryl group, an aralkyl group, and an aryloxyalkyl group. Specific examples of the (meth) acrylate having an aromatic group include benzyl (meth) acrylate, phenyl (meth) acrylate, and phenoxyethyl (meth) acrylate.

  Examples of the (meth) acrylate having a polyalkylene glycol structural unit include polyethylene glycol (degree of polymerization = 1 to 10) methyl ether (meth) acrylate, polyethylene glycol (degree of polymerization = 1 to 10) ethyl ether (meth) acrylate, and polyethylene. (Meth) acrylates having a polyethylene glycol structural unit such as glycol (degree of polymerization = 1 to 10) propyl ether (meth) acrylate; polypropylene glycol (degree of polymerization = 1 to 10) methyl ether (meth) acrylate, polypropylene glycol (degree of polymerization) = 1 to 10) (meth) amine having a polypropylene glycol structural unit such as ethyl ether (meth) acrylate and polypropylene glycol (degree of polymerization = 1 to 10) propyl ether (meth) acrylate Relate and the like.

  Examples of the (meth) acrylate having an alkoxy group include methoxyethyl (meth) acrylate and ethoxyethyl (meth) acrylate.

  The (meth) acrylate having an oxygen-containing heterocyclic group is preferably a (meth) acrylate having a 4- to 6-membered oxygen-containing heterocyclic group. Specific examples of the (meth) acrylate having an oxygen-containing heterocyclic group include tetrahydrofurfuryl (meth) acrylate, (3-ethyloxetane-3-yl) methyl (meth) acrylate, and (2-methyl-2-ethyl-). 1,3-dioxolan-4-yl) methyl (meth) acrylate, cyclic trimethylolpropaneformal (meth) acrylate, 2-[(2-tetrahydropyranyl) oxy] ethyl (meth) acrylate, 1,3-dioxane- (Meth) acrylate and the like.

  Examples of the (meth) acrylate having a tertiary amino group include 2- (dimethylamino) ethyl (meth) acrylate and N, N-dimethylaminopropyl (meth) acrylate.

  Examples of the aromatic vinyl monomer include styrene, α-methylstyrene, 4-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methoxystyrene, 2-hydroxymethylstyrene, 1-vinylnaphthalene, and the like.

  Examples of the vinyl monomer having a hetero ring include 2-vinylthiophene, N-methyl-2-vinylpyrrole, 2-vinylpyridine, 4-vinylpyridine, N-phenylmaleimide, N-benzylmaleimide, and N-cyclohexylmaleimide. No.

  Examples of the vinylamide include N-vinylformamide, N-vinylacetamide, 1-vinyl-2-pyrrolidone, N-vinyl-ε-caprolactam, and the like.

  Examples of the vinyl carboxylate include vinyl acetate, vinyl pivalate, and vinyl benzoate.

  Examples of the vinyl monomer having a tertiary amino group include N, N-dimethylallylamine.

  Examples of the vinyl monomer having a quaternary ammonium base include N-methacryloylaminoethyl-N, N, N-dimethylbenzylammonium chloride.

  Examples of the α-olefin include 1-hexene, 1-octene, 1-decene, and the like.

  Examples of the dienes include butadiene, isoprene, 4-methyl-1,4-hexadiene, and 7-methyl-1,6-octadiene.

  The content of the structural unit (a-3) is preferably 50% by mass or more, more preferably 57% by mass or more, even more preferably 64% by mass or more in 100% by mass of the whole copolymer, and 94.9% by mass. %, Preferably 89.5% by mass or less, more preferably 84% by mass or less.

  The structural unit (a-3) has a (meth) acrylate having a linear alkyl group, a (meth) acrylate having a branched alkyl group, a (meth) acrylate having a cyclic alkyl group, and an aromatic group ( It is preferable to contain a structural unit derived from at least one monomer selected from the group consisting of (meth) acrylates.

  In addition, (meth) acrylate having a linear alkyl group, (meth) acrylate having a branched alkyl group, (meth) acrylate having a cyclic alkyl group, and an aromatic group in 100% by mass of the entire copolymer. The content of the structural unit derived from at least one monomer selected from the group consisting of (meth) acrylates is preferably 50% by mass or more, more preferably 57% by mass or more, and still more preferably 64% by mass or more. The content is preferably 90% by mass or less, more preferably 80% by mass or less, and further preferably 75% by mass or less.

(1-1-4. Production method of copolymer (A))
The copolymer (A) can be produced by radically polymerizing two or more vinyl monomers, and is preferably obtained by living radical polymerization (by polymerization using a living radical polymerization method). Obtained).

  In the conventional radical polymerization method (free radical polymerization method), not only the initiation reaction and the growth reaction, but also the termination reaction and the chain transfer reaction deactivate the growth terminal, resulting in a mixture of polymers having various molecular weights and heterogeneous compositions. Tends to be easy. The living radical polymerization method, while maintaining the simplicity and versatility of the conventional radical polymerization method, a termination reaction and chain transfer hardly occur, and the growth terminal grows without deactivation, so while having a high molecular weight, It is easy to precisely control the molecular weight distribution and produce a polymer having a uniform composition.

  Therefore, it is considered that the copolymer produced by the living radical polymerization method has an advantage that it has a small amount of low molecular weight components (oligomers) and a small amount of transfer contaminants (such as adhesive residue) when used in an adhesive composition. Can be Further, since the structural units ((a-1) to (a-3)) are uniformly polymerized in each polymer molecule, when used in the pressure-sensitive adhesive composition, a small radiation dose and a small amount of a photoinitiator are used. It is considered that even in the amount, the adhesive strength can be sufficiently reduced by radiation curing of the adhesive layer.

  In the living radical polymerization method, a vinyl monomer forming a structural unit (a-1), a vinyl monomer forming a structural unit (a-2), and a vinyl monomer forming a structural unit (a-3) as required By using a mixture with a monomer (sometimes simply referred to as “vinyl monomer”), a random copolymer can be obtained. Further, a block copolymer can be obtained by sequentially reacting the vinyl monomers constituting the copolymer (A). For example, in the case of a diblock copolymer, a method in which the first block is first produced, and the vinyl monomer constituting the second block is polymerized in the first block; the second block is produced first. And a method of polymerizing a vinyl monomer constituting the first block to the second block. In the case of a triblock copolymer, the first block is first produced, the first block is polymerized with the vinyl monomer constituting the second block, and further the vinyl monomer constituting the third block is produced. And a method of producing by polymerization.

  In the living radical polymerization method, a method using a transition metal catalyst (ATRP method); a method using a sulfur-based reversible chain transfer agent (RAFT method); There is a method such as a method used (TERP method). Since the ATRP method uses an amine-based complex, it cannot be used without protecting the acidic group of the vinyl monomer having an acidic group. In the RAFT method, when various types of monomers are used, a low molecular weight distribution is unlikely to occur, and there may be a problem such as a sulfur odor or coloring. Among these methods, it is preferable to use the TERP method from the viewpoints of diversity of usable monomers, control of molecular weight in a polymer region, uniform composition, and coloring.

  The TERP method is a method of polymerizing a radical polymerizable compound (vinyl monomer) using an organic tellurium compound as a chain transfer agent. For example, WO2004 / 14848, WO2004 / 14962, WO No. 2004/072126 and WO 2004/096870.

Specific polymerization methods of the TERP method include the following (a) to (d).
(A) A vinyl monomer is polymerized using an organic tellurium compound represented by the general formula (2).
(B) A vinyl monomer is polymerized using a mixture of an organic tellurium compound represented by the general formula (2) and an azo-based polymerization initiator.
(C) A vinyl monomer is polymerized using a mixture of an organic telluride compound represented by the general formula (2) and an organic ditelluride compound represented by the general formula (3).
(D) A vinyl monomer is polymerized using a mixture of an organic telluride compound represented by the general formula (2), an azo-based polymerization initiator, and an organic ditelluride compound represented by the general formula (3).

［一般式（２）において、Ｒ²¹は、炭素数１〜８のアルキル基、アリール基または芳香族ヘテロ環基を示す。Ｒ²²およびＲ²³は、それぞれ独立に、水素原子または炭素数１〜８のアルキル基を示す。Ｒ²⁴は、炭素数１〜８のアルキル基、アリール基、置換アリール基、芳香族ヘテロ環基、アルコキシ基、アシル基、アミド基、オキシカルボニル基、シアノ基、アリル基またはプロパルギル基を示す。
一般式（３）において、Ｒ²¹は、炭素数１〜８のアルキル基、アリール基または芳香族ヘテロ環基を示す。］

[In the general formula (2), R ²¹ represents an alkyl group having 1 to 8 carbon atoms, an aryl group, or an aromatic heterocyclic group. R ²² and R ²³ each independently represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. R ²⁴ represents an alkyl group having 1 to 8 carbon atoms, an aryl group, a substituted aryl group, an aromatic heterocyclic group, an alkoxy group, an acyl group, an amide group, an oxycarbonyl group, a cyano group, an allyl group or a propargyl group.
In the general formula (3), R ²¹ represents an alkyl group having 1 to 8 carbon atoms, an aryl group or an aromatic heterocyclic group. ]

The group represented by R ²¹ is an alkyl group having 1 to 8 carbon atoms, an aryl group or an aromatic heterocyclic group, and is specifically as follows.
Examples of the alkyl group having 1 to 8 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, hexyl, and heptyl. And a straight-chain or branched-chain alkyl group such as an octyl group, and a cyclic alkyl group such as a cyclohexyl group. It is preferably a straight-chain or branched-chain alkyl group having 1 to 4 carbon atoms, and more preferably a methyl group or an ethyl group.
Examples of the aryl group include a phenyl group and a naphthyl group.
Examples of the aromatic heterocyclic group include a pyridyl group, a furyl group, and a thienyl group.

Groups represented by R ²² and R ²³ are each independently a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, each group is specifically as follows.
Examples of the alkyl group having 1 to 8 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, hexyl, and heptyl. And a straight-chain or branched-chain alkyl group such as an octyl group, and a cyclic alkyl group such as a cyclohexyl group. It is preferably a straight-chain or branched-chain alkyl group having 1 to 4 carbon atoms, and more preferably a methyl group or an ethyl group.

The group represented by R ²⁴ is an alkyl group having 1 to 8 carbon atoms, an aryl group, a substituted aryl group, an aromatic heterocyclic group, an alkoxy group, an acyl group, an amide group, an oxycarbonyl group, a cyano group, an allyl group or It is a propargyl group, which is specifically as follows.
Examples of the alkyl group having 1 to 8 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, hexyl, and heptyl. And a linear or branched alkyl group such as a octyl group, and a cyclic alkyl group such as a cyclohexyl group. It is preferably a straight-chain or branched-chain alkyl group having 1 to 4 carbon atoms, and more preferably a methyl group or an ethyl group.
Examples of the aryl group include a phenyl group and a naphthyl group. Preferably it is a phenyl group.
Examples of the substituted aryl group include a phenyl group having a substituent and a naphthyl group having a substituent. Examples of the substituent of the aryl group having a substituent include a halogen atom, a hydroxy group, an alkoxy group, an amino group, a nitro group, a cyano group, and a carbonyl-containing group represented by —COR ²¹¹ (R ²¹¹ is a carbon atom). An alkyl group having 1 to 8 carbon atoms, an aryl group, an alkoxy group having 1 to 8 carbon atoms or an aryloxy group), a sulfonyl group, and a trifluoromethyl group. Further, these substituents are preferably substituted one or two times.
Examples of the aromatic heterocyclic group include a pyridyl group, a furyl group, and a thienyl group.
As the alkoxy group, a group in which an alkyl group having 1 to 8 carbon atoms is bonded to an oxygen atom is preferable. For example, a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, an n-butoxy group, a sec-butoxy group, a tert- Butoxy, pentyloxy, hexyloxy, heptyloxy, octyloxy and the like.
Examples of the acyl group include an acetyl group, a propionyl group, and a benzoyl group.
Examples of the amide group include -CONR ²²¹ R ²²² (R ²²¹ and R ²²² are each independently a hydrogen atom, an alkyl group or an aryl group having 1 to 8 carbon atoms).
As the oxycarbonyl group, a group represented by —COOR ²³¹ (R ²³¹ is a hydrogen atom, an alkyl group or an aryl group having 1 to 8 carbon atoms) is preferable. For example, a carboxy group, a methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl Group, n-butoxycarbonyl group, sec-butoxycarbonyl group, tert-butoxycarbonyl group, n-pentyloxycarbonyl group, phenoxycarbonyl group and the like. Preferred oxycarbonyl groups include a methoxycarbonyl group and an ethoxycarbonyl group.
As the allyl group, -CR ²⁴¹ R ²⁴² -CR ²⁴³ = CR ²⁴⁴ R ²⁴⁵ (R ²⁴¹ and R ²⁴² are each independently a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, R ²⁴³ , R ²⁴⁴ and R ²⁴⁵ are Each independently represents a hydrogen atom, an alkyl group or an aryl group having 1 to 8 carbon atoms, and the respective substituents may be connected by a cyclic structure).
Examples of the propargyl group include -CR ²⁵¹ R ²⁵² -C≡CR ²⁵³ (R ²⁵¹ and R ²⁵² are a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, and R ²⁵³ is a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. , An aryl group or a silyl group).

  Specific examples of the organic tellurium compound represented by the general formula (2) include (methylteranylmethyl) benzene, (methylteranylmethyl) naphthalene, ethyl-2-methyl-2-methylteranyl-propionate, and ethyl-2-yl. Methyl-2-n-butylteranyl-propionate, (2-trimethylsiloxyethyl) -2-methyl-2-methylterranyl-propionate, (2-hydroxyethyl) -2-methyl-2-methylterranyl-propionate or (3-trimethylsilylpropargyl) ) -2-Methyl-2-methylteranyl-propionate and the like organic compounds described in WO 2004/14848, WO 2004/14962, WO 2004/072126, and WO 2004/096870. All of tellurium compounds Can Shimesuru.

  Specific examples of the organic ditelluride compound represented by the general formula (3) include dimethyl ditelluride, diethyl ditelluride, di-n-propyl ditelluride, diisopropyl ditelluride, dicyclopropyl ditelluride, and dicyclopropyl ditelluride. -N-butyl ditelluride, di-s-butyl ditelluride, di-t-butyl ditelluride, dicyclobutyl ditelluride, diphenyl ditelluride, bis- (p-methoxyphenyl) ditelluride, bis- (p-aminophenyl) ditelluride, bis Examples include-(p-nitrophenyl) ditelluride, bis- (p-cyanophenyl) ditelluride, bis- (p-sulfonylphenyl) ditelluride, dinaphthyl ditelluride, dipyridyl ditelluride, and the like.

  The azo-based polymerization initiator can be used without particular limitation as long as it is an azo-based polymerization initiator used in ordinary radical polymerization. For example, 2,2′-azobis (isobutyronitrile) (AIBN), 2,2′-azobis (2-methylbutyronitrile) (AMBN), 2,2′-azobis (2,4-dimethylvaleronitrile) ) (ADVN), 1,1′-azobis (1-cyclohexanecarbonitrile) (ACHN), dimethyl-2,2′-azobisisobutyrate (MAIB), 4,4′-azobis (4-cyanovaleric acid) ) (ACVA), 1,1′-azobis (1-acetoxy-1-phenylethane), 2,2′-azobis (2-methylbutylamide), 2,2′-azobis (4-methoxy-2,4 -Dimethylvaleronitrile) (V-70), 2,2′-azobis (2-methylamidinopropane) dihydrochloride, 2,2′-azobis [2- (2-imidazolin-2-yl) Lopan], 2,2′-azobis [2-methyl-N- (2-hydroxyethyl) propionamide], 2,2′-azobis (2,4,4-trimethylpentane), 2-cyano-2-propyl Examples include azoformamide, 2,2′-azobis (N-butyl-2-methylpropionamide), and 2,2′-azobis (N-cyclohexyl-2-methylpropionamide).

  In the polymerization step, the vinyl monomer and the organic tellurium compound of the general formula (2) are further added to the vinyl monomer and the organic tellurium compound of the general formula (2) in accordance with the type of the vinyl monomer for the purpose of accelerating the reaction and controlling the molecular weight and the molecular weight distribution. An azo polymerization initiator and / or an organic ditelluride compound of the general formula (3) are mixed. At this time, examples of the inert gas include nitrogen, argon, and helium. Preferably, argon and nitrogen are good.

  The amount of the vinyl monomer used in (a), (b), (c) and (d) may be appropriately adjusted depending on the physical properties of the desired copolymer (A). The amount of the vinyl monomer is preferably 200 to 30,000 mol per 1 mol of the organic tellurium compound of the general formula (2).

  When the organic tellurium compound of the general formula (2) and the azo-based polymerization initiator (b) are used in combination, the azo-based polymerization initiator is used in an amount of 0.01 mol to 10 mol per 1 mol of the organic tellurium compound of the general formula (2). It is preferable that

  When the organic telluride compound of the general formula (2) and the organic ditelluride compound of the general formula (3) are used in combination, 1 mol of the organic tellurium compound of the general formula (2) may be used in combination with the organic compound of the general formula (3). It is preferable that the ditelluride compound be 0.01 mol to 100 mol.

  When the organic telluride compound of the general formula (2), the organic ditelluride compound of the general formula (3), and the azo-based polymerization initiator are used in combination with each other, 1 mol of the organic tellurium compound of the general formula (2) may be used. The amount of the organic ditelluride compound of the formula (3) is preferably from 0.01 mol to 100 mol, and the amount of the azo-based polymerization initiator is preferably from 0.01 mol to 10 mol per 1 mol of the organic ditelluride compound of the general formula (3).

  The polymerization reaction can be carried out without a solvent, but may be carried out by using an aprotic solvent or a protic solvent generally used in radical polymerization and stirring the mixture. Examples of usable aprotic solvents include, for example, anisole, benzene, toluene, N, N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), acetone, 2-butanone (methyl ethyl ketone), dioxane, propylene glycol monomethyl ether acetate, and chloroform. , Carbon tetrachloride, tetrahydrofuran (THF), ethyl acetate, propylene glycol monomethyl ether acetate or trifluoromethylbenzene. Examples of the protic solvent include water, methanol, ethanol, isopropanol, n-butanol, ethyl cellosolve, butyl cellosolve, 1-methoxy-2-propanol, hexafluoroisopropanol, and diacetone alcohol.

  The amount of the solvent to be used may be appropriately adjusted. For example, the amount is preferably 0.01 ml or more, more preferably 0.05 ml or more, still more preferably 0.1 ml or more, and 50 ml or less, per 1 g of the vinyl monomer. It is preferably 10 ml or less, more preferably 1 ml or less.

  The reaction temperature and reaction time may be appropriately adjusted depending on the molecular weight or molecular weight distribution of the obtained copolymer (A), and the mixture is usually stirred at 0 ° C to 150 ° C for 1 minute to 100 hours. The TERP method can obtain a high yield and a precise molecular weight distribution even at a low polymerization temperature and a short polymerization time. At this time, the pressure is usually set at normal pressure, but may be increased or decreased.

  After the completion of the polymerization reaction, the desired copolymer (A) can be separated from the obtained reaction mixture by removing the solvent used, residual vinyl monomers, and the like by ordinary separation and purification means.

The growth terminal of the copolymer obtained by the polymerization reaction is in the form of -TeR ²¹ derived from a tellurium compound (where R ²¹ is the same as described above), and is deactivated by an operation in the air after the completion of the polymerization reaction. However, tellurium atoms may remain. Since the copolymer having a tellurium atom at the terminal is colored or has poor thermal stability, it is preferable to remove the tellurium atom.

  As a method for removing tellurium atoms, a radical reduction method using tributylstannane or a thiol compound; a method of adsorbing with activated carbon, silica gel, activated alumina, activated clay, molecular sieves, a polymer adsorbent, etc .; A method for adsorbing a metal: a peroxide such as hydrogen peroxide or benzoyl peroxide is added, or air or oxygen is blown into the system to oxidize and decompose the tellurium atom at the terminal of the copolymer, and to wash with water or an appropriate solution. A liquid-liquid extraction method or a solid-liquid extraction method for removing residual tellurium compounds by combining solvents; a purification method in a solution state such as ultrafiltration for extracting and removing only those having a specific molecular weight or less; Also, these methods can be used in combination.

  The copolymer (A) having a radiation polymerizable group introduced into the side chain is, for example, a crosslinkable functional group of the copolymer obtained as described above, a functional group capable of polymerizing with the crosslinkable functional group, It can also be produced by reacting a compound having a radiopolymerizable functional group in one molecule.

(1-2 Crosslinking Agent (B))
The crosslinking agent (B) used in the present invention is a compound having two or more reactive groups capable of reacting with the crosslinking functional group of the copolymer (A) in one molecule. The crosslinking agent (B) is not particularly limited, and examples thereof include an isocyanate crosslinking agent, an epoxy crosslinking agent, an aziridine crosslinking agent, a metal chelate crosslinking agent, a melamine resin crosslinking agent, and a urea resin crosslinking agent. . Among these, isocyanate-based cross-linking agents, epoxy-based cross-linking agents, and aziridine-based cross-linking agents are preferable, and from the viewpoint of easily controlling the degree of progress of the cross-linking reaction, and from the viewpoint of adhesion to the substrate, isocyanate-based cross-linking agents are more preferable. preferable.

  The isocyanate-based cross-linking agent is a compound having two or more isocyanate groups as reactive groups (including an isocyanate-regenerating functional group in which isocyanate groups are temporarily protected by a blocking agent or quantification) in one molecule. The isocyanate-based crosslinking agents may be used alone or in combination of two or more.

  Examples of the isocyanate-based crosslinking agent include aromatic isocyanates such as tolylene diisocyanate and xylene diisocyanate; alicyclic isocyanates such as isophorone diisocyanate; and aliphatic isocyanates such as hexamethylene diisocyanate. More specifically, for example, lower aliphatic polyisocyanates such as butylene diisocyanate and hexamethylene diisocyanate; alicyclic isocyanates such as cyclopentylene diisocyanate, cyclohexylene diisocyanate, and isophorone diisocyanate; 2,4-tolylene diisocyanate; Aromatic diisocyanates such as 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate, polymethylene polyphenyl isocyanate; trimethylolpropane / tolylene diisocyanate trimer adduct, trimethylolpropane / hexamethylene diisocyanate trimer adduct, Isocyanate adducts such as isocyanurate of hexamethylene diisocyanate; trimethylolpropane of xylylene diisocyanate Adducts; trimethylolpropane adducts of hexamethylene diisocyanate; polyether polyisocyanates, polyester polyisocyanates, and adducts of these with various polyols, polyfunctionalized with isocyanurate bonds, burette bonds, allophanate bonds, etc. One or more selected from isocyanates; and the like can be used. Of these, aliphatic isocyanates are preferably used, and isocyanurates of aliphatic isocyanates (eg, isocyanurates of hexamethylene diisocyanate) are more preferred.

  The epoxy-based crosslinking agent refers to a compound having two or more epoxy groups as a reactive group in one molecule. The epoxy-based crosslinking agents may be used alone or in combination of two or more.

  Examples of the epoxy crosslinking agent include bisphenol A, epichlorohydrin type epoxy resin, ethylene glycidyl ether, N, N, N ′, N′-tetraglycidyl-m-xylenediamine, diglycidylaniline, diamineglycidylamine, , 3-Bis (N, N-diglycidylaminomethyl) cyclohexane, 1,6-hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether , Polypropylene glycol diglycidyl ether, sorbitol polyglycidyl ether, glycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, Lyserine diglycidyl ether, glycerin triglycidyl ether, polyglycerol polyglycidyl ether, sorbitan polyglycidyl ether, trimethylolpropane polyglycidyl ether, adipic acid diglycidyl ester, o-phthalic acid diglycidyl ester, triglycidyl-tris (2-hydroxy Ethyl) isocyanurate, resorcin diglycidyl ether, bisphenol-S-diglycidyl ether and the like.

  The aziridine-based crosslinking agent refers to a compound having two or more aziridine groups as a reactive group in one molecule. The aziridine-based crosslinking agent may be used alone or in combination of two or more.

  Examples of the aziridine-based crosslinking agent include tris-2,4,6- (1-aziridinyl) -1,3,5-triazine, tris [1- (2-methyl) -aziridinyl] phosphine oxide, and hexa [1- (2 -Methyl) -aziridinyl] triphosphatriazine and the like.

  The content of the reactive group in the crosslinking agent (B) is preferably 0.5 mmol / g or more, more preferably 1.0 mmol / g or more, and still more preferably 3.0 mmol / g or more, and 20 mmol / g or less. Is preferred, more preferably 10 mmol / g or less, and even more preferably 8.0 mmol / g or less. When the content of the reactive group of the crosslinking agent (B) is 0.5 mmol / g or more, the cohesive strength before irradiation becomes good, and when the content is 20 mmol / g or less, the crosslinking density does not become too high, and Has good adhesive strength.

  The content of the crosslinking agent (B) in the pressure-sensitive adhesive composition is preferably at least 0.01 part by mass, more preferably at least 0.1 part by mass, and still more preferably 100 parts by mass of the copolymer (A). Is at least 0.5 part by mass, preferably at most 20 parts by mass, more preferably at most 15 parts by mass, further preferably at most 10 parts by mass, particularly preferably at most 5.0 parts by mass. If the content of the crosslinking agent (B) is at least 0.01 part by mass, the cohesive strength before irradiation will be good, and if it is at most 20 parts by mass, the crosslinking density will not be too high, and the adhesive strength before irradiation will be low. It will be good.

  In the pressure-sensitive adhesive composition, the molar ratio of the reactive group of the crosslinking agent (B) to the crosslinking functional group of the copolymer (A) (the molar amount of the reactive group / the molar amount of the crosslinking functional group) is as follows. , 0.001 or more, more preferably 0.01 or more, still more preferably 0.03 or more, preferably 1.0 or less, more preferably 0.5 or less, and still more preferably 0.2 or less. .

(1-3 compound (C))
The compound (C) used in the present invention is at least one compound selected from the group consisting of a rust inhibitor and a primary antioxidant, and is preferably a rust inhibitor. The compound (C) may be used alone or in combination of two or more. By containing the compound (C), the adhesive performance of the pressure-sensitive adhesive tape can be improved, and fine stains on the surface of the adherend, which are considered to be caused by the pressure-sensitive adhesive tape, can be suppressed.

(1-3-1 Rust inhibitor)
The rust inhibitor includes a compound that prevents rust (rust) and corrosion of metal. The rust inhibitor is not particularly limited, but includes, for example, amine compounds, azole compounds, nitrites, ammonium benzoate, ammonium phthalate, ammonium stearate, ammonium palmitate, ammonium oleate, ammonium carbonate, dicyclohexylamine benzoate Acid salts, urea, urotropin, thiourea, phenyl carbamate, cyclohexylammonium-N-cyclohexylcarbamate (CHC), and the like are used as active ingredients. From the viewpoint of compatibility with the copolymer (A), the rust inhibitor is a 5-membered aromatic compound containing two or more hetero atoms, and at least one of those hetero atoms is a nitrogen atom. Certain azole compounds are preferred.

  Examples of the azole compound include compounds having an azole ring structure, and derivatives, amine salts, and metal salts thereof. Examples of the azole ring structure include an imidazole ring, a pyrazole ring, an oxazole ring, an isoxazole ring, a thiazole ring, an isothiazole ring, a selenazole ring, a 1,2,3-triazole ring, a 1,2,4-triazole ring, 2,5-oxadiazole ring, 1,3,4-oxadiazole ring, 1,2,3-thiadiazole ring, 1,2,4-thiadiazole ring, 1,3,4-thiadiazole ring, tetrazole ring, Examples thereof include a 1,2,3,4-thiatriazole ring. The azole compound may have a substituent on the azole ring.

  As the azole compound, a compound containing a condensed ring structure of an azole ring and another ring (for example, a benzene ring or a naphthalene ring) is preferable. Examples of the fused ring structure include an indazole structure (a structure in which a pyrazole ring and a benzene ring are fused), a benzimidazole structure (a structure in which an imidazole ring and a benzene ring are fused), and a benzothiazole structure (a structure in which a thiazole ring and a benzene ring are fused). And a benzotriazole structure (a structure in which a triazole ring and a benzene ring are condensed) and a naphthotriazole structure (a structure in which a triazole ring and a naphthalene ring are condensed). Among these, compounds having a benzotriazole structure are more preferable.

  Examples of the azole compound include imidazole, pyrazole, oxazole, isoxazole, thiazole, isothiazole, selenazole, 1,2,3-triazole, 1,2,4-triazole, and 1,2,5-oxadiazole. 1,3,4-oxadiazole, 1,2,3-thiadiazole, 1,2,4-thiadiazole, 1,3,4-thiadiazole, tetrazole, 1,2,3,4-thiatriazole, 3- Amino-1,2,4-triazole, 5-phenyl-1H-tetrazole and the like.

  Examples of the azole compound having a condensed ring structure include alkyl benzotriazoles such as 5-methylbenzotriazole, 5-ethylbenzotriazole, 5-n-propylbenzotriazole, 5-isobutylbenzotriazole, and 4-methylbenzotriazole; N-alkylbenzotriazole; alkoxybenzotriazole such as 5-methoxybenzotriazole; carboxybenzotriazole; aminobenzotriazole; alkylaminobenzotriazole; alkylaminosulfonylbenzotriazole; mercaptobenzotriazole; hydroxybenzotriazole; Nitrobenzotriazole; halobenzotriazole such as 5-chlorobenzotriazole; hydroxyalkylbenzo Riazor; hydro-benzotriazole; (substituted aminomethyl) - tolyltriazole; bisbenzotriazole; naphthotriazole; mercaptobenzothiazole; aminobenzothiazole; and these amine salts, these metal salts and the like.

  As the azole compound, a triazole compound represented by the following formula (4) is more preferable. By having the structure represented by the following formula (4), it is possible to further increase the adhesive strength and reduce the stain caused by the adhesive tape.

［一般式（４）において、ｎは０〜４の整数を示す。Ｒ⁴¹は、炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数６〜１４のアリール基、カルボキシ基、炭素数２〜６のカルボキシアルキル基、−ＮＲ⁴¹¹Ｒ⁴¹²（Ｒ⁴¹¹およびＲ⁴¹²は、それぞれ独立して水素原子、炭素数１〜１０のアルキル基）、−ＳＯ₂ＮＨＲ⁴¹¹（Ｒ⁴¹¹は、炭素数１〜１０のアルキル基）、−Ｒ⁴¹³ＮＲ⁴¹¹Ｒ⁴¹²（Ｒ⁴¹¹およびＲ⁴¹²は、それぞれ独立して水素原子、炭素数１〜１０のアルキル基；Ｒ⁴¹³は炭素数１〜６のアルキレン基）、メルカプト基、ヒドロキシ基、ニトロ基、ハロゲン原子、炭素数１〜６のヒドロキシアルキル基、または炭素数１〜６のアルコキシカルボニル基を示す。ｎが２以上の場合、複数存在するＲ⁴¹は、同一でも異なっていてもよい。
Ｒ⁴²は、水素原子、炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基、炭素数６〜１４のアリール基、アミノ基、−ＮＲ⁴²¹Ｒ⁴²²（Ｒ⁴²¹およびＲ⁴²²は、それぞれ独立して水素原子、炭素数１〜１０のアルキル基）、−Ｒ⁴²³ＮＲ⁴²¹Ｒ⁴²²（Ｒ⁴²¹およびＲ⁴²²は、それぞれ独立して水素原子、炭素数１〜１０のアルキル基；Ｒ⁴²³は炭素数１〜６のアルキレン基）、メルカプト基、または、炭素数１〜１２のアルコキシカルボニル基示す。］

[In general formula (4), n shows the integer of 0-4. R ⁴¹ is an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an aryl group having 6 to 14 carbon atoms, a carboxy group, a carboxyalkyl group having 2 to 6 carbon atoms, —NR ⁴¹¹ R ⁴¹² ( R ⁴¹¹ and R ⁴¹² are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon ^{_{atoms), - SO 2 NHR 411 (}} R 411 represents an alkyl group having 1 to 10 carbon atoms), - R ⁴¹³ NR ⁴¹¹ R ⁴¹² (R ⁴¹¹ and R ⁴¹² are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms; R ⁴¹³ is an alkylene group having 1 to 6 carbon atoms), a mercapto group, a hydroxy group, a nitro group, a halogen atom, It represents a hydroxyalkyl group having 1 to 6 carbon atoms or an alkoxycarbonyl group having 1 to 6 carbon atoms. When n is 2 or more, a plurality of R ⁴¹ may be the same or different.
R ⁴² is a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 14 carbon atoms, an amino group, —NR ⁴²¹ R ⁴²² (R ⁴²¹ and R ⁴²² are Each independently represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms; -R ⁴²³ NR ⁴²¹ R ⁴²² (R ⁴²¹ and R ⁴²² each independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms; R ⁴²³ Represents an alkylene group having 1 to 6 carbon atoms), a mercapto group, or an alkoxycarbonyl group having 1 to 12 carbon atoms. ]

In the above formula (4), R ⁴¹ is a substituent on a benzene ring. When n in the formula (4) is 2 or more, n R ^{41 s} included in the formula (4) may be the same as or different from each other. R ⁴¹ and R ⁴² may be the same or different.

The alkyl group represented by R ⁴¹ or R ⁴² may be a linear alkyl group or a branched alkyl group, but is preferably a linear alkyl group. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, and a tert-butyl group.
Examples of the alkoxy group represented by R ⁴¹ or R ⁴² include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, and a hexyloxy group.
Examples of the aryl group represented by R ⁴¹ or R ⁴² include a phenyl group.
Examples of the carboxyalkyl group represented by R ⁴¹ or R ⁴² include a carboxymethyl group, a carboxyethyl group, and a carboxypropyl group.
Examples of the halogen atom represented by R ⁴¹ or R ⁴² include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.
Examples of the hydroxyalkyl group represented by R ⁴¹ or R ⁴² include a hydroxymethyl group, a hydroxyethyl group, a hydroxypropyl group, a hydroxybutyl group, and the like.
Examples of the alkoxycarbonyl group represented by R ⁴¹ or R ⁴² include a methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group, a butoxycarbonyl group, and the like.

  Preferred examples of the benzotriazole-based compound represented by the formula (4) include 1,2,3-benzotriazole, 5-methylbenzotriazole, 4-methylbenzotriazole, carboxybenzotriazole and the like.

(1-3-2 Primary antioxidant)
The primary antioxidant has a hydrogen radical donating ability for a peroxy radical. That is, it is a compound having at least one hydrogen atom in its molecule which is rapidly extracted by a peroxy radical.

  As the primary antioxidant, an aromatic compound substituted by a hydroxy group or a primary or secondary amino group is preferable, and a phenol derivative having an alkyl group at an ortho position or a diarylamine derivative is more preferable. As the primary antioxidant, a hindered phenol-based antioxidant is particularly preferred.

  Examples of the hindered phenol-based antioxidant include compounds represented by the following general formula (5).

［一般式（５）において、Ｒ⁵¹は水素原子またはメチル基を示す。Ｒ⁵²およびＲ⁵³は、一方が水素原子、他方が１価の有機基を示す。Ｒ⁵⁴は１価の有機基を示す。］

[In the general formula (5), R ⁵¹ represents a hydrogen atom or a methyl group. One of R ⁵² and R ⁵³ represents a hydrogen atom, and the other represents a monovalent organic group. R ⁵⁴ represents a monovalent organic group. ]

The monovalent organic group represented by R ^{52 to} R ⁵⁴ is a hydrocarbon group (saturated or unsaturated, linear or branched, and may have a cyclic structure in the structure), It may contain a hetero atom or a halogen atom. Heteroatoms include nitrogen, oxygen, sulfur, phosphorus and the like.

^Examples of the combination of R ⁵² and R ⁵³ include a combination in which R ⁵² is a hydrogen atom and R ⁵³ is a monovalent organic group, and a combination in which R ⁵² is a monovalent organic group and R ⁵³ is a hydrogen atom. , ^R52 is a monovalent organic group and ^R53 is a hydrogen atom. In this case, R ⁵² is preferably an alkyl group, more preferably a methyl group, a tert-butyl group, or a tert-pentyl group.

  Specific examples of hindered phenolic antioxidants include 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, pentaerythritol-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 2-tert-butyl-6- (3-tert-butyl-2-hydroxy-5-methylbenzyl) -4-methyl Phenyl acrylate, 2- [1- (2-hydroxy-3,5-di-tert-pentylphenyl) ethyl] -4,6-di-tert-pentylphenyl acrylate, N, N′-hexamethylenebis (3, 5-di-tert-butyl-4-hydroxy-hydrocinnamamide), 1,6-hexanediol-bis [3- (3,5- -Tert-butyl-4-hydroxyphenyl) propionate], 3,9-bis [2- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] 1,1-dimethylethyl] 2,4,8,10-tetraoxaspiro [5.5] undecane, tris- (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, isooctyl-3- (3,5-di- tert-butyl-4-hydroxyphenyl) propionate, 4,4′-thiobis (6-tert-butyl-3-methylphenol), 2-tert-butyl-6-methyl-4- {3-[(2,4 , 8,10-Tetra-tert-butyldibenzo [d, f] [1,3,2] dioxaphosphepin-6-yl) oxy] propyl} pheno 2,6-di-tert-butyl-p-cresol, 4,4′-butylidenebis (6-tert-butyl-m-cresol), 3- (3,5-di-tert-butyl-4-hydroxy) Phenyl) stearyl propionate, 2,2′-methylenebis (6-tert-butyl-p-cresol), 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, bis [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionic acid] [ethylenebis (oxyethylene)] and the like.

  The content of the compound (C) in the pressure-sensitive adhesive composition is preferably at least 0.01 part by mass, more preferably at least 0.05 part by mass, and still more preferably 100 parts by mass of the copolymer (A). It is 0.1 part by mass or more, preferably 5.0 parts by mass or less, more preferably 1.0 part by mass or less, and further preferably 0.5 part by mass or less. When the content of the compound (C) is 0.01 parts by mass or more, the effect of suppressing stains on the surface of the adherend derived from the pressure-sensitive adhesive is further improved. In particular, when the amount is 0.1 parts by mass or more, in addition to a sufficient effect of suppressing stain stains, the adhesive strength to a metal adherend can be further improved. When the content of the compound (C) is 5.0 parts by mass or less, precipitation of the compound (C) at the interface between the pressure-sensitive adhesive layer and the adherend can be suppressed.

  When a rust inhibitor is used as the compound (C), the content of the rust inhibitor in the pressure-sensitive adhesive composition is preferably at least 0.01 part by mass based on 100 parts by mass of the copolymer (A). More preferably at least 0.05 part by mass, even more preferably at least 0.1 part by mass, preferably at most 5.0 parts by mass, more preferably at most 1.0 part by mass, still more preferably at most 0.5 part by mass. It is.

  When a primary antioxidant is used as the compound (C), the content of the primary antioxidant in the pressure-sensitive adhesive composition is 0.01 parts by mass or more based on 100 parts by mass of the copolymer (A). It is preferably at least 0.05 part by mass, more preferably at least 0.1 part by mass, preferably at most 5.0 parts by mass, more preferably at most 1.0 part by mass, still more preferably at most 0.5 part by mass. Part or less.

(1-4. Other additives)
In the pressure-sensitive adhesive composition, in addition to the copolymer (A), the crosslinking agent (B), and the compound (C), a radiation-polymerizable compound (D), a photopolymerization initiator, a crosslinking accelerator, a crosslinking retarder, Tackifying resins, photosensitizers, gas generating agents that generate gas by radiation, dyes, pigments, dyes, fluorescent brighteners, wetting agents, surface tension adjusters, thickeners, fungicides, preservatives, Oxygen absorbers, ultraviolet absorbers, near infrared absorbers, water-soluble quenchers, antioxidants other than compound (C), fragrances, metal deactivators, nucleating agents, antistatic agents, alkylating agents, flame retardants, Other additives such as a lubricant and a processing aid can also be compounded and used, and these are appropriately selected and mixed according to the use and purpose of use of the pressure-sensitive adhesive. Specific examples of the other additives include, for example, the following.

(1-4-1. Radiation-polymerizable compound (D))
The pressure-sensitive adhesive composition can be used by mixing a radiation-polymerizable compound (D) as necessary. The radiation polymerizable compound (D) is a compound having two or more radioactive polymerizable groups in one molecule, excluding the copolymer (A). The radiation polymerizable compound (D) may be used alone or in combination of two or more.

  The radiation polymerizable compound (D) may have a crosslinkable functional group of the copolymer (A) or a reactive group of the crosslinker (B). When the radiation polymerizable compound (D) has a crosslinkable functional group or a reactive group, it can be bonded to the copolymer (A) directly or via a crosslinker (B). In addition, it is preferable that the said radiation polymerizable compound (D) does not have the crosslinkable functional group which the said copolymer (A) has, and the reactive group which the said crosslinking agent (B) has.

  It is preferable that the number of the radioactive polymerizable group in one molecule of the radiation polymerizable compound (D) is six or less. When the number (hereinafter, also referred to as “the number of polymerizable groups”) is 7 or more, the radiation-sensitive polymerizable compound (D) is polymerized by irradiation with radiation, so that the pressure-sensitive adhesive layer hardens, and the adhesive strength is increased. Is excessively reduced, and the possibility of chip falling off in the expanding step may increase. On the other hand, when the number of the polymerization groups is less than 2, the decrease in the adhesive force due to the irradiation of the radiation is reduced, and the possibility that the pickup failure occurs may be increased. Therefore, it is preferable that the number of the polymerization groups is three or more. Further, from the viewpoint of high compatibility with the copolymer (A), the radiation polymerizable group of the radiation polymerizable compound (D) is preferably a (meth) acrylolyl group.

  The radiation polymerizable compound (D) preferably has a weight average molecular weight (Mw) of 100 to 30,000. If the molecular weight is excessively small, there is a concern that it will volatilize during the production process, and at this time, the stability of the composition of the pressure-sensitive adhesive layer will decrease. The molecular weight of the radiation-polymerizable compound (D) is determined based on the weight average molecular weight (Mw) from the viewpoint of more stably achieving both the reduction of the possibility of volatilization in the production process and the enhancement of the function of plasticizing the pressure-sensitive adhesive layer. ) Is more preferably 200 to 20,000, even more preferably 300 to 10,000.

  In addition, when the said radiation polymerizable compound (D) does not have the crosslinkable functional group which the said copolymer (A) has, and the reactive group which the said crosslinking agent (B) has, the said radiation polymerizable compound ( The weight average molecular weight (Mw) of D) is preferably at least 500, more preferably at least 1,000, even more preferably at least 1,500, preferably at most 30,000, more preferably at most 20,000, Preferably it is 10,000 or less. When the Mw of the radiation-polymerizable compound (D) is 500 or more, the molecular chain of the copolymer (A) is easily restricted, and the adhesiveness of the adhesive layer can be sufficiently reduced.

  As the radiation polymerizable compound (D), two or more compounds having different molecular weights may be used in combination. In this case, the weight average molecular weight of the compound having the smallest molecular weight is preferably 100 or more, more preferably 200 or more, still more preferably 300 or more, and preferably less than 1,000. The number of radioactive polymerizable groups in the molecule of the compound having the smallest molecular weight is preferably 3 or more and 6 or less. The compound having the largest molecular weight preferably has a weight average molecular weight of 1,000 or more, more preferably 1,500 or more, preferably 10,000 or less, more preferably 5,000 or less, and still more preferably 3,000 or less. It is as follows. The number of radioactive polymerizable groups in one molecule of the compound having the largest molecular weight is preferably 2 or more and 3 or less, more preferably 2 or more.

  When the radiation polymerizable compound (D) contains two or more compounds having different molecular weights, the mass ratio (D1 / D2) of the compound (D1) having the smallest molecular weight to the compound (D2) having the largest molecular weight is 0. It is preferably at least 0.5, more preferably at least 1.5, even more preferably at least 3.0, preferably at most 10, more preferably at most 8.0, even more preferably at most 6.0.

  Examples of the radiation polymerizable compound (D) include at least one compound selected from the group consisting of a polyfunctional (meth) acrylate compound and a polyfunctional oligomer.

  Examples of the polyfunctional (meth) acrylate compound include trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol monohydroxypenta (meth) acrylate, and dipentaerythritol Hexa (meth) acrylate, 1,4-butylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, polyethylene glycol di (meth) acrylate, oligoester (meth) acrylate and the like may be mentioned. it can.

  Examples of the polyfunctional oligomer include urethane (meth) acrylate-based oligomers. The urethane (meth) acrylate oligomer includes a polyol compound (including a high molecular weight polyol compound such as a polyester type or a polyether type) and a polyvalent isocyanate compound (for example, 2,4-tolylene diisocyanate, 2,6- Tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, diphenylmethane-4,4-diisocyanate, isophorone diisocyanate, etc.) (Meth) acrylate having a hydroxyl group (for example, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, polyethylene glycol Rate, obtained by reacting a polyethylene glycol methacrylate).

  The content of the radiation-polymerizable compound (D) in the pressure-sensitive adhesive composition is preferably at least 10 parts by mass, more preferably at least 20 parts by mass, and still more preferably 30 parts by mass, per 100 parts by mass of the copolymer (A). It is at least 50 parts by mass, preferably at most 50 parts by mass, more preferably at most 40 parts by mass. When the content of the radiation-polymerizable compound (D) is within the above range, irradiation with radiation can sufficiently reduce the adhesive strength of the pressure-sensitive adhesive layer and easily peel off the pressure-sensitive adhesive tape.

(1-4-2. Photopolymerization initiator)
If necessary, a photopolymerization initiator can be added to the pressure-sensitive adhesive composition. As the photopolymerization initiator, acetophenone-based initiator, benzoin ether-based initiator, benzophenone-based initiator, hydroxyalkylphenone-based initiator, thioxanthone-based initiator, acylphosphine oxide-based photopolymerization initiator, amine-based initiator And the like. Among these, specific examples of the acetophenone-based initiator include diethoxyacetophenone and benzyldimethyl ketal. Specific examples of the benzoin ether-based initiator include benzoin and benzoin methyl ether. Specific examples of the benzophenone-based initiator include benzophenone and methyl o-benzoylbenzoate. Specific examples of the hydroxyalkylphenone-based initiator include 1-hydroxy-cyclohexyl-phenyl-ketone. Specific examples of the thioxanthone-based initiator include 2-isopropylthioxanthone and 2,4-dimethylthioxanthone. Specific examples of the acylphosphine oxide-based photopolymerization initiator include 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide. Specific examples of the amine initiator include triethanolamine and ethyl 4-dimethylbenzoate.

  As the photopolymerization initiator, one type may be used alone, or two or more types may be used in combination. The content of the photopolymerization initiator may be appropriately adjusted according to, for example, the content of the radiation-polymerizable compound (D), the irradiation amount of radiation when completely cured, and the like. The content of the photopolymerization initiator is not particularly limited, but is preferably 1 part by mass to 30 parts by mass, more preferably 5 parts by mass to 15 parts by mass based on 100 parts by mass of the radiation polymerizable compound (D). When the value is equal to or more than the lower limit, the pressure-sensitive adhesive layer is sufficiently cured to form a three-dimensional network, and the adhesive force of the pressure-sensitive adhesive layer is reduced. When the content is equal to or less than the upper limit, transfer contaminants (adhesive residue and the like) caused by a low molecular weight polymer polymerized by irradiation with radiation can be avoided.

(1-4-3. Crosslinking accelerator)
The pressure-sensitive adhesive composition can be used by blending a crosslinking accelerator, if necessary.

  Examples of the crosslinking accelerator include an organic tin compound and the like. The crosslinking accelerator may be used alone or in combination of two or more. Examples of the organotin compound include dibutyltin dilaurate, dioctyltin dilaurate, dibutyltin dioctylate, and the like.

  The content of the crosslinking accelerator in the pressure-sensitive adhesive composition of the present invention is preferably at least 0.01 part by mass, more preferably at least 0.02 part by mass, based on 100 parts by mass of the copolymer (A). The content of the crosslinking accelerator is preferably 0.04 parts by mass or more, preferably 0.5 parts by mass or less, more preferably 0.4 parts by mass or less, and still more preferably 0.3 parts by mass or less. By doing so, it becomes possible to obtain an excellent crosslinking promoting effect.

(1-4-4. Crosslinking retarder)
The pressure-sensitive adhesive composition can be used by blending a crosslinking retarder, if necessary. The crosslinking retarder is, for example, a compound that can suppress an excessive increase in viscosity of the pressure-sensitive adhesive composition by blocking an isocyanate group included in the pressure-sensitive adhesive composition containing the isocyanate-based cross-linking agent. . The type of the crosslinking retarder is not particularly limited, but for example, β-diketones such as acetylacetone, hexane-2,4-dione, heptane-2,4-dione, octane-2,4-dione; Β-Keto esters such as methyl acetoacetate, ethyl acetoacetate, propyl acetoacetate, butyl acetoacetate, octyl acetoacetate, oleyl acetoacetate, lauryl acetoacetate, and stearyl acetoacetate; benzoylacetone and the like can be used. The crosslinking retarders may be used alone or in combination of two or more.

  The content of the crosslinking retarder that can be added to the pressure-sensitive adhesive composition is preferably at least 0.3 part by mass, more preferably at least 1.0 part by mass, based on 100 parts by mass of the copolymer (A). It is more preferably at least 2.0 parts by mass, preferably at most 20 parts by mass, more preferably at most 10 parts by mass, further preferably at most 5.0 parts by mass. By adjusting the content of the crosslinking retarder in the above range, after blending the crosslinking agent (B) into the pressure-sensitive adhesive composition, excessive increase in viscosity and gelation of the pressure-sensitive adhesive composition are suppressed. The storage stability (pot life) of the composition can be extended.

(1-4-5. Tackifying resin)
In the pressure-sensitive adhesive composition of the present invention, a tackifier resin other than the copolymer (A) can be blended and used, if necessary. As the tackifying resins, petroleum such as rosin resin, terpene resin such as terpene phenol resins, C ₅ petroleum resins, C ₉ petroleum resins, C ₅ / C ₉ petroleum resins such as rosin ester resin Base resin, xylene resin, styrene resin, coumarone indene resin and the like. Among these, rosin ester resins and terpene phenol resins are preferred. The pressure-sensitive adhesive composition may be used alone or in combination of two or more.

  The rosin ester-based resin is a rosin resin containing abietic acid as a main component, a disproportionated rosin resin, a hydrogenated rosin resin, a dimer of a resin acid such as abietic acid (polymerized rosin resin), or the like. It is a resin obtained by A part of the hydroxyl group of the alcohol used for the esterification is contained in the resin without being used for the esterification, whereby the hydroxyl value is adjusted. Examples of the alcohol include polyhydric alcohols such as ethylene glycol, glycerin, and pentaerythritol. A resin obtained by esterifying a rosin resin is a rosin ester resin, a resin obtained by esterifying a disproportionated rosin resin is a disproportionated rosin ester resin, a resin obtained by esterifying a hydrogenated rosin resin is a hydrogenated rosin ester resin, and a polymerized rosin resin. The resin obtained by esterifying the resin is a polymerized rosin ester resin. The terpene phenol resin is a resin obtained by polymerizing terpene in the presence of phenol.

  The tackifier resin preferably has a hydroxyl value of 170 mgKOH / g to 250 mgKOH / g. When the hydroxyl value is too small, the effect of compounding the tackifier resin is hardly obtained, and when the hydroxyl value is too large, the pressure-sensitive adhesive component may be phase-separated to lower the tackiness. The hydroxyl value can be measured by JIS K0070 (1992) 7.1 neutralization titration method.

  The tackifier resin preferably has a softening temperature of 70C to 170C. If the softening temperature is too low, the effect of compounding the tackifier resin is hardly obtained, and if the softening temperature is too high, the pressure-sensitive adhesive layer may be hard and easily peeled off. The softening temperature can be measured by the JIS K2207 ring and ball method.

  The tackifier resin is preferably used after the ethylenically unsaturated bond is saturated by hydrogenation. When the tackifying resin has an excess ethylenically unsaturated bond, the radiation-polymerizable group in the pressure-sensitive adhesive layer upon irradiation of the pressure-sensitive adhesive layer reacts with the ethylenically unsaturated bond of the tackifying resin, and the pressure-sensitive adhesive composition Curing reaction may not proceed sufficiently. In addition, the radiation applied to the pressure-sensitive adhesive layer is used for an addition reaction between the tackifier resins, and the curing reaction of the pressure-sensitive adhesive layer may not proceed sufficiently.

  The content of the tackifier resin in the pressure-sensitive adhesive composition is preferably 5 parts by mass or more, and more preferably 50 parts by mass or less based on 100 parts by mass of the copolymer (A). If the content of the tackifying resin is small, the effect of compounding the tackifying resin is difficult to be obtained, and if the content of the tackifying resin is too large, transfer contaminants (such as adhesive residue) may increase.

(1-5. Method for producing pressure-sensitive adhesive composition)
The pressure-sensitive adhesive composition can be manufactured by mixing the copolymer (A), the crosslinking agent (B), the compound (C), and other additives used as necessary. The pressure-sensitive adhesive composition may contain a solvent derived from the production of the copolymer (A), or may be further diluted with a suitable solvent to have a viscosity suitable for forming a pressure-sensitive adhesive layer. Solution may be used.

  Examples of the solvent include aliphatic hydrocarbons such as hexane and heptane; aromatic hydrocarbons such as toluene and xylene; halogenated hydrocarbons such as methylene chloride and ethylene chloride; acetone, methyl ethyl ketone, 2-pentanone, isophorone and cyclohexanone. Ketones such as ethyl acetate, butyl acetate, etc .; cellosolve solvents such as ethyl cellosolve; glycol ether solvents such as propylene glycol monomethyl ether; These solvents may be used alone or as a mixture of two or more.

  The amount of the solvent to be used may be appropriately adjusted so that the pressure-sensitive adhesive composition has a viscosity suitable for coating, and is not particularly limited. However, from the viewpoint of coating properties, the solid content concentration of the pressure-sensitive adhesive composition is 10%. It is preferable to use it so that it may be 95% by mass to 95% by mass.

(2. Base film)
The base film is not particularly limited as long as it can transmit radiation, and plastic, elastomer, rubber and the like can be used. It is necessary to select a material in consideration of radiation transmittance so that the pressure-sensitive adhesive layer is cured and the adhesive strength is reduced when the substrate film is irradiated with radiation. When ultraviolet rays are selected from the radiation and the radiation-curable pressure-sensitive adhesive composition is cured by the irradiation, it is necessary to select a base film having good ultraviolet transmittance.

  The thickness of the base film is not particularly limited and is appropriately selected, but is preferably 30 μm or more, more preferably 50 μm or more, still more preferably 80 μm or more, particularly from the viewpoint of radiation transmittance and strong elongation characteristics. Preferably it is 90 μm or more, preferably 250 μm or less, more preferably 200 μm or less, further preferably 150 μm or less, particularly preferably 120 μm or less.

  Examples of materials that can be selected as the base film include films composed of polyolefin resins such as polyethylene and polypropylene, polyester resins such as polyethylene terephthalate (PET), and plastic materials such as polyvinyl chloride, ethylene vinyl alcohol, and ionomer resins. Is mentioned. The plastic materials can be used alone or in combination of two or more. The plastic material may contain an antistatic agent, a heat stabilizer and the like, and a mixture of two or more compatible plastic materials, that is, a polymer alloy or the like can also be used.

  The base film may be subjected to a surface treatment by an oxidation method, a concavo-convex method, or the like, if desired, on one or both surfaces for the purpose of improving the adhesion to a layer provided on the surface. Examples of the oxidation method include a corona discharge treatment, a plasma treatment, a chromic acid treatment (wet method), a flame treatment, a hot air treatment, and an ozone / ultraviolet irradiation treatment. Examples of the unevenness method include a sand blast method and a solvent treatment method. These surface treatment methods are appropriately selected according to the type of the base film, but generally, the corona discharge treatment method is preferably used from the viewpoint of the effect and the operability. Further, one obtained by subjecting one or both surfaces to a primer treatment can also be used as the base film.

  The thickness of the pressure-sensitive adhesive layer may be appropriately adjusted according to the use of the pressure-sensitive adhesive tape. For example, when used as a semiconductor processing tape such as a back-grinding tape or a dicing tape, there is no particular limitation as long as it does not impair the expandability and unevenness followability of the base film, but is usually preferably 1 μm or more, and more preferably. Is 2 μm or more, more preferably 5 μm or more, particularly preferably 10 μm or more, preferably 100 μm or less, more preferably 50 μm or less, further preferably 35 μm or less, particularly preferably 20 μm or less. If the pressure-sensitive adhesive layer is excessively thin, the adhesion tends to vary.If the pressure-sensitive adhesive layer is excessively thick, it becomes difficult to control the adhesive force by irradiation, or cohesive failure occurs inside the pressure-sensitive adhesive layer during pickup. There is a possibility that the probability of occurrence will increase. When the pressure-sensitive adhesive layer has a multilayer structure, the total thickness of all the layers is preferably within the above range.

  The content of the radiation-polymerizable group in the pressure-sensitive adhesive layer is preferably 0.1 mmol / g or more, more preferably 0.2 mmol / g or more, further more preferably 0.5 mmol / g or more, and 10 mmol / g or less. Is more preferable, more preferably 5 mmol / g or less, and still more preferably 2 mmol / g or less. When the content of the radiation-polymerizable group is within the above range, by irradiating the radiation, the adhesive force of the adhesive layer is sufficiently reduced, and the adhesive tape can be easily peeled. When the pressure-sensitive adhesive layer is a multilayer, the content of the radiation-polymerizable group in the pressure-sensitive adhesive composition preferably satisfies the above range when all the pressure-sensitive adhesive layers are regarded as one layer, More preferably satisfies the above range.

  The gel fraction of the pressure-sensitive adhesive layer is preferably 20% by mass or more, more preferably 35% by mass or more, further preferably 50% by mass or more, and particularly preferably 65% by mass or more from the viewpoint of durability and adhesive strength. , 100% by mass or less, more preferably 90% by mass or less, further preferably 80% by mass or less, particularly preferably 70% by mass or less. If the gel fraction is too low, durability tends to be insufficient due to insufficient cohesive force, and residue remains upon peeling. The gel fraction can be controlled by the amount of the crosslinking agent in the pressure-sensitive adhesive composition, the crosslinking temperature, and the crosslinking time.

(3. Method of forming pressure-sensitive adhesive layer)
The method for forming the pressure-sensitive adhesive layer is not particularly limited, and examples thereof include the following methods (1) and (2).
(1) A method in which an adhesive composition is applied to one or both surfaces of a base film using various coating devices, the solvent is removed by drying, and curing is performed as necessary.
(2) The pressure-sensitive adhesive composition is applied to the release surface of the release film on which the release treatment has been performed by using various coating devices, the solvent is removed by drying, and transferred to one or both surfaces of the base film. After that, cure as needed.

  Examples of the coating device include a reverse roll coater, a gravure coater, a forward roll coater, a knife coater, a wire bar coater, a doctor blade coater, a slot die coater, a curtain coater, a dip coater, and the like.

  The drying temperature at the time of drying and removing the solvent is preferably 40C to 200C, more preferably 60C to 180C. The drying time is preferably 5 seconds to 20 minutes, more preferably 10 seconds to 10 minutes. Examples of drying means include hot air, near infrared rays, infrared rays, and high frequency. The curing conditions include, for example, about 3 to 7 days at 23 ° C.

  The pressure-sensitive adhesive tape may have a release film (separator) on the surface of the pressure-sensitive adhesive layer until use. Without using a separate release film, a release layer is provided on the surface of the base film opposite to the surface on which the pressure-sensitive adhesive layer is laminated, and the surface of the release layer is wound into a roll such that the exposed surface side of the pressure-sensitive adhesive layer is in contact with the surface. It may be turned or stacked in a stack. The release film is used as a protective material for the pressure-sensitive adhesive layer, and is peeled off when the pressure-sensitive adhesive tape of the present invention is attached to an adherend.

  Examples of the release film include paper such as glassine paper, coated paper, and laminated paper, and films obtained by applying a release agent such as a silicone resin to various plastic films. As the plastic film used for the release film, those mentioned as the base film can be appropriately used. Although the thickness of the release film is not particularly limited, it is usually 10 μm to 150 μm.

<Semiconductor device manufacturing method>
The method for manufacturing a semiconductor device according to the present invention includes: an attaching step of attaching the adhesive tape of the present invention to a semiconductor wafer or a substrate and a ring frame; and a dicing step of dicing the semiconductor wafer or the substrate into a semiconductor chip or a semiconductor component. An irradiation step of irradiating the adhesive tape with radiation, an expanding step of extending the adhesive tape to widen a gap between the semiconductor chips or semiconductor components, and a pickup step of picking up a semiconductor chip or semiconductor component from the adhesive tape. Including.

  In the attaching step, the adhesive tape is attached to the semiconductor wafer or the substrate and the ring frame. Examples of the semiconductor wafer include silicon, silicon carbide, gallium arsenide (gallium arsenide), gallium phosphide, indium phosphide, and gallium nitride. The semiconductor wafer may have a through electrode. Examples of the substrate include a package substrate in which a semiconductor chip is sealed with a resin, a ceramic substrate on which the semiconductor chip is mounted, and the like.

  In the dicing step, a semiconductor wafer or a substrate is diced into semiconductor chips or semiconductor components. For dicing, known methods such as blade dicing, laser dicing, and plasma dicing can be used.

  In the irradiating step, the adhesive tape is irradiated with radiation. The pressure-sensitive adhesive layer is three-dimensionally meshed and cured by irradiation with radiation, and the adhesive strength of the pressure-sensitive adhesive layer is reduced.

  The radiation is preferably applied from the substrate film side. The radiation is preferably an ultraviolet ray or an electron beam, and more preferably an ultraviolet ray which is relatively easy to introduce irradiation equipment.

When ultraviolet rays are used as the radiation, near-ultraviolet rays including ultraviolet rays having a wavelength of about 200 nm to 380 nm may be used for ease of handling. The amount of ultraviolet light may be appropriately selected depending on the type of the radioactive polymerizable group and the thickness of the pressure-sensitive adhesive layer, and is usually about 50 mmJ / cm ^{2 to} 500 mmJ / cm ² , and is about 100 mmJ / cm ^{2 to} 450 mmJ / cm. ² is ^{preferred, 20mmJ / cm 2 ~400mmJ / cm} 2 is more preferable. The ultraviolet illumination is usually 50mW / cm ² ~500mW / cm ² or so, preferably from ^{100mW / cm 2 ~450mW / cm 2} , more preferably ^{200mW / cm 2 ~400mW / cm 2} . There is no particular limitation on the ultraviolet light source, and for example, a high-pressure mercury lamp, a metal halide lamp, a light emitting diode or the like is used.

  When an electron beam is used as the radiation, the accelerating voltage may be appropriately selected depending on the type of the radioactive polymerizable group and the thickness of the pressure-sensitive adhesive layer, and is preferably about 10 kV to 1,000 kV in general. . The irradiation dose may be set in a range where the radioactive polymerizable group appropriately reacts and the pressure-sensitive adhesive layer is cured, and is usually selected in a range of 10 krad to 1000 krad. The electron beam source is not particularly limited. For example, various electron beam accelerators such as Cockloft-Walton type, Van degraft type, resonance transformer type, insulating core transformer type, or linear type, dynamitron type high frequency type, etc. may be used. Can be.

  In the expanding / pickup step, the adhesive tape is stretched in order to widen the gap between the semiconductor chips or semiconductor components, and the semiconductor chips or semiconductor components are pushed up with needle pins or the like. Thereafter, the semiconductor chip or the semiconductor component is sucked by a vacuum collet or air tweezers, and is separated from the adhesive layer of the adhesive tape and picked up. At this time, since the adhesive tape of the present invention has a sufficiently reduced adhesive strength by irradiation with radiation, the peeling between the semiconductor chip or semiconductor component and the adhesive layer becomes easy, and a good pickup property is obtained. Can be

  Hereinafter, the present invention will be described in more detail based on specific examples. The present invention is not limited to the following embodiments at all, and can be implemented with appropriate changes within a scope that does not change the gist of the present invention. The polymerization rate, weight average molecular weight (Mw) and molecular weight distribution (PDI) of the copolymer, the gel fraction of the pressure-sensitive adhesive layer, the adhesive strength of the pressure-sensitive adhesive tape, the residual adhesive and the stain of the adherend were determined by the following methods. Was evaluated according to

The meanings of the abbreviations are as follows.
BA: n-butyl acrylate DMAAm: N, N-dimethylacrylamide 2-HEA: 2-hydroxyethyl acrylate CHA: cyclohexyl acrylate BTEE: ethyl-2-methyl-2-n-butylteranyl-propionate V-70: 2,2 ′ -Azobis (4-methoxy-2,4-dimethylvaleronitrile)
AIBN: 2,2'-azobis (isobutyronitrile)

(Polymerization rate)
¹ H-NMR was measured (solvent: CDCl ₃ , internal standard: trimethylsilane (TMS)) using a nuclear magnetic resonance (NMR) measuring device (manufactured by Bruker Biospin, model: AVANCE500 (frequency: 500 MHz)). . With respect to the obtained NMR spectrum, the integral ratio between the peak of the vinyl group derived from the monomer and the peak of the ester side chain derived from the polymer was determined, and the polymerization rate of the monomer was calculated.

(Weight average molecular weight (Mw) and molecular weight distribution (PDI))
It was determined by gel permeation chromatography (GPC) using a high performance liquid chromatograph (Model: HLC-8320GPC, manufactured by Tosoh Corporation). Two columns of TSKgel Super Multipore HZ-H (manufactured by Tosoh Corporation) were used as the column, a tetrahydrofuran solution as a mobile phase, and a differential refractometer as a detector. The measurement conditions were a column temperature of 40 ° C., a sample concentration of 10 mg / mL, a sample injection amount of 10 μm, and a flow rate of 0.2 mL / min. Polystyrene (molecular weight 2,890,000, 1,090,000, 775,000, 427,000, 190,000, 96,400, 37,900, 10,200, 2,630,440) used as a standard substance Then, a calibration curve (calibration curve) was prepared, and the weight average molecular weight (Mw) and the number average molecular weight (Mn) were measured. The molecular weight distribution (PDI = Mw / Mn) was calculated from the measured values.

(Gel fraction)
The mass W1 of a wire mesh (200 mesh) cut out from a width of 50 mm and a length of 100 mm was measured. 0.1 g of the pressure-sensitive adhesive layer was collected from the pressure-sensitive adhesive tape, wrapped with a wire mesh so that the pressure-sensitive adhesive did not fall off, to prepare a test piece, and the mass W2 of the test piece was measured. The test piece was put in a glass bottle, 40 g of ethyl acetate was poured, and the mixture was shaken lightly, and then left still in an oven at 60 ° C. for 24 hours. After standing, the test piece was taken out of the glass bottle, left at room temperature for 12 hours, and dried in a vacuum oven at 80 ° C. for 4 hours. The dried test piece was cooled to room temperature, the mass W3 was measured, and the gel fraction was calculated from the following equation.
Gel fraction (% by mass) = ((W3-W1) / (W2-W1)) × 100

(Adhesive strength (before UV irradiation))
The adhesive strength (before UV irradiation) of the adhesive tape is measured in accordance with JIS Z0237 (2009) measuring method of adhesive strength (Method 1: Test method in which tape and sheet are peeled at 180 ° from stainless steel test plate). did. Specifically, an adherend (Stainless steel plate (SUS304BA) Ra 50 nm (JIS B 0601 (1994)) or a copper plate (C1220P phosphorous deoxidized copper (JIS H3100 (2012)) Ra 95 nm (JIS B 0601 (1994)) whose surface has been cleaned. )), Using a crimping device (roller mass 2 kg) to measure the adhesive force when peeled off from the adherend by 180 °, using a tensile tester (manufactured by Imada Seisakusho, SV-). The test temperature was 25 ° C., the peeling speed was 300 mm / min, the width of the pressure-sensitive adhesive tape was 25 mm, and the length was 300 mm. Was neglected, and the adhesive strength measurements for 50 mm lengths that were subsequently peeled off the test plate were averaged.

(Adhesive strength (after UV irradiation))
In the test for the adhesive strength (before UV irradiation), the adhesive tape (after UV irradiation) was irradiated with UV on the adhesive tape pressed on the adherend, and then pulled 180 ° to the adherend. The adhesive strength when peeled was measured.
The UV irradiation is performed a plurality of times using a conveyor UV irradiator (manufactured by Heraeus Co., Ltd., LC-6 system, H valve) so that the adhesive tape has an illuminance of 250 mW / cm ² and an integrated light amount of 700 mJ / cm ² or more. Was. After UV irradiation, the adhesive strength (after UV irradiation) was measured immediately. From the measurement results, the rate of decrease in tackiness due to UV irradiation was calculated.
Reduction rate (%) = 100 × (adhesive strength before UV irradiation−adhesive strength after UV irradiation) / adhesive strength before UV irradiation

(Remaining glue)
A copper plate (C5191, phosphor bronze (JIS H3110 (2012)), length 50 mm, width 50 mm) was heated on a hot plate set at 60 ° C. An adhesive tape (length 30 mm, width 30 mm) from which the separator was peeled was placed on the copper plate, and these were pressed by one reciprocation of a hand roller weighing 2 kg. After the pressure bonding, the substrate was left for 24 hours at 23 ° C. and 50% RH. Next, using a conveyor-type UV irradiator (made by Heraeus: LC-6 system, H valve), UV was applied several times from the adhesive tape surface so that the illuminance was 250 mW / cm ² and the integrated light amount was 700 mJ / cm ² or more. Was irradiated. After UV irradiation, the adhesive tape was peeled off, and the presence or absence of the remaining adhesive on the adherend was confirmed by a scanning electron microscope (JCM-6000, manufactured by JEOL Ltd., acceleration voltage: 5 kV, magnification: 1000 times). The evaluation was based on the following criteria.
：: There is no residue.
Δ: There is a slight residue.
X: There are many residues.

(Stain on the adherend surface (oxide film))
A copper plate (C5191, phosphor bronze (JIS H3110 (2012)), length 50 mm, width 50 mm) was heated on a hot plate set at 60 ° C. An adhesive tape (length 30 mm, width 30 mm) from which the separator was peeled was placed on the copper plate, and these were pressed by one reciprocation of a hand roller weighing 2 kg. After the pressure bonding, the substrate was left at 23 ° C. and a 50% RH environment for 24 hours. Next, UV irradiation was performed several times from the adhesive tape surface using a conveyor type UV irradiator (made by Heraeus: LC-6 system, H valve) so that the illuminance was 250 mW / cm ² and the integrated light amount was 700 mJ / cm ² or more. Was irradiated.
After UV irradiation, the adhesive tape was peeled off, and the surface of the adhesive tape to which the adhesive tape was bonded was laser-wavelength: 532 nm, light-attenuating filter: D1, grading: 600 gr / mm, and exposed by a microscopic laser Raman spectrometer (Horiba Seisakusho, LabRam ARAMIS). Time: Measured under the condition of 1 s. As a comparative object, the same measurement was performed on a copper plate before the adhesive tape was bonded. From the measurement results obtained, read the intensity of the peaks present in peaks and 1750～1840Cm ^-1 present in 1650～1710Cm ^-1, was calculated change amount of the peak intensity before the adhesive tape bonding. Note that the smaller the amount of change in the peak intensity, the smaller the spot stain is.

<Production of copolymer>
(Synthesis example 1)
In a flask equipped with a stirrer, a reflux condenser, a nitrogen gas inlet tube, and a temperature sensor, 280 g (2185 mmol) of BA, 100 g (1009 mmol) of DMAAm, 20 g (172 mmol) of 2-HEA, and 43.54 mg of V-70. (0.14 mmol) and 300 g of ethyl acetate were charged, and after replacing the inside of the polymerization system with nitrogen gas, 107.7 μl (0.47 mmol) of BTEE was added, followed by stirring at 33 ° C. for 24 hours to carry out polymerization. ^{From the} result of ¹ H-NMR measurement, the polymerization rate was 92.5%.

  After completion of the reaction, ethyl acetate for concentration adjustment was added to the reaction solution to obtain a solution of the copolymer A having a solid content of 22.0% by mass and a viscosity of 6,760 mPa · s. The obtained copolymer A had a Mw of 736,000, a PDI of 2.12, a content of the structural unit (a-1) of 25% by mass, and a content of the structural unit (a-2) of 5% by mass. The content of the structural unit (a-3) was 70% by mass, the amount of hydroxy group was 0.43 mmol / g, and the Tg was -28 ° C. The content of each structural unit and the amount of hydroxy in the copolymer were calculated from the ratio of vinyl monomers used in the polymerization reaction.

(Synthesis example 2)
In a flask equipped with a stirrer, reflux condenser, nitrogen gas inlet tube and temperature sensor, 300 g (2341 mmol) of BA, 80 g (519 mmol) of CHA, 20 g (172 mmol) of 2-HEA, and 37.96 mg of V-70. (0.12 mmol), 300 g of ethyl acetate were charged, and after replacing the inside of the polymerization system with nitrogen gas, 107.7 μl (0.47 mmol) of BTEE was added, followed by stirring at 60 ° C. for 24 hours to carry out polymerization. ^{From the} result of ¹ H-NMR measurement, the polymerization rate was 90.3%.

  After completion of the reaction, ethyl acetate for concentration adjustment was added to the reaction solution to obtain a solution of the copolymer B having a solid content of 15.8% by mass and a viscosity of 2,550 mPa · s. The obtained copolymer B had a Mw of 930,000, a PDI of 2.01, a content of the structural unit (a-1) of 0% by mass, and a content of the structural unit (a-2) of 5% by mass. The content of the structural unit (a-3) was 95% by mass, the amount of hydroxy group was 0.43 mmol / g, and the Tg was -41 ° C. The content of each structural unit and the amount of hydroxy in the copolymer were calculated from the ratio of vinyl monomers used in the polymerization reaction.

(Synthesis example 3)
In a flask equipped with a stirrer, a reflux condenser, a nitrogen gas inlet tube, and a temperature sensor, 280 g (2185 mmol) of BA, 100 g (1009 mmol) of DMAAm, 20 g (172 mmol) of 2-HEA, and 720 mg (4.39 mmol) of AIBN. ) And 300 g of ethyl acetate were charged, and the inside of the polymerization system was replaced with nitrogen gas, followed by stirring at 80 ° C for 12 hours to carry out polymerization. ^{From the} result of ¹ H-NMR measurement, the polymerization rate was 90.1%.

  After completion of the reaction, ethyl acetate for concentration adjustment was added to the reaction solution to obtain a solution of the copolymer C having a solid content of 20.3% by mass and a viscosity of 2,750 mPa · s. The obtained copolymer C had a Mw of 771,000, a PDI of 7.24, a content of the structural unit (a-1) of 25% by mass, and a content of the structural unit (a-2) of 5% by mass. The content of the structural unit (a-3) was 70% by mass, the amount of hydroxy group was 0.43 mmol / g, and the Tg was -28 ° C. The content of each structural unit and the amount of hydroxy in the copolymer were calculated from the ratio of vinyl monomers used in the polymerization reaction.

<Production of pressure-sensitive adhesive composition>
(Adhesive composition No. 1)
With respect to 455 parts by mass of the solution of copolymer A obtained in Synthesis Example 1 (100 parts by mass of the copolymer component, 355 parts by mass of ethyl acetate), 0.51 part by mass of an isocyanate compound as a crosslinking agent, and a crosslinking accelerator 0.20 parts by mass of an organotin compound, 2.56 parts by mass of acetylacetone as a crosslinking retarder, and urethane acrylate No. 1 as a radiation polymerizable compound. 1 and 32 parts by mass of urethane acrylate No. 1 2 parts by mass, 4 parts by mass of TPO as a photopolymerization initiator, 0.5 parts by mass of BTA as a rust preventive agent, and an appropriate amount of ethyl acetate. 1 was obtained. Note that the molar ratio (NCO / OH) between the OH group of the copolymer A and the NCO group of the isocyanate compound is 0.07. The NCO equivalent of the organotin compound to the isocyanate compound is 0.094. The NCO equivalent of acetylacetone to the isocyanate compound is 9.1.

(Adhesive composition Nos. 2 to 8)
Except that the composition was changed as described in Table 2, the pressure-sensitive adhesive composition No. In the same manner as in No. 1, the pressure-sensitive adhesive composition No. 2 to 8 were produced.

Isocyanate compound: Duranate (registered trademark) TPA-100 (an isocyanurate of hexamethylene diisocyanate, NCO content 23.1% by mass) manufactured by Asahi Kasei Corporation
Urethane acrylate No. 1: UA-306I (pentaerythritol triacrylate isophorone diisocyanate urethane prepolymer, hexafunctional, molecular weight about 800, manufactured by Kyoeisha Chemical Co., Ltd.)
Urethane acrylate No. 2: UA-160TM (a urethane acrylate oligomer obtained by adding an isocyanate compound to polyethylene oxide and reacting an acrylate having a hydroxy group, bifunctional, molecular weight: about 1600, manufactured by Shin-Nakamura Chemical Co., Ltd.)
BTA: Otsuka Chemical Co., Ltd., 1,2,3-benzotriazole Sumilizer (registered trademark) GP: Sumitomo Chemical Co., Ltd., 2-tert-butyl-6-methyl-4- {3-[(2,4,8,10 -Tetra-tert-butyldibenzo [d, f] [1,3,2] dioxaphosphepin-6-yl) oxy] propyl} phenol Irganox (registered trademark) 1010: manufactured by BASF, pentaerythritol tetrakis [3] -(3,5-di-tert-butyl-4-hydroxyphenyl) propionate]
Organotin compound: manufactured by Nitto Kasei Co., Ltd., Neostan (registered trademark) U810
TPO: Irgacure (registered trademark) TPO (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide) manufactured by BASF

<Manufacture of adhesive tape>
(Adhesive tape No.1)
The prepared pressure-sensitive adhesive composition (coating liquid) is applied to a 25-μm-thick separator (release-treated PET film) using a baker-type applicator so that the coating layer after drying has a thickness of 20 μm, and is then heated at 60 ° C. in an oven. For 2 minutes and then at 120 ° C. for 3 minutes. Thereafter, a polyvinyl chloride film having a thickness of 100 μm was bonded to the pressure-sensitive adhesive-coated surface using a hand roller while taking care not to allow air to enter. This was aged in an atmosphere of 40 ° C. for 72 hours to obtain an adhesive tape.

(Adhesive tape No. 2 to 8)
The pressure-sensitive adhesive composition No. No. 1 was used as the adhesive composition No. Except having changed to adhesive tape No. 2 to 8, In the same manner as in No. 1, the adhesive tape No. 2 to 8 were produced.

  As shown in Table 3, the adhesive tape No. In Nos. 1 to 3, the pressure-sensitive adhesive layer contains a (meth) acrylic copolymer (A), a crosslinking agent (B), and a compound (C), and the content of the radiation-polymerizable group in the solid content is The pressure-sensitive adhesive composition is formed from 0.1 mmol / g to 10 mmol / g. These adhesive tape Nos. Nos. 1 to 3 have a high adhesive strength before UV irradiation, and the adhesive strength is sufficiently reduced after UV irradiation. Moreover, when the adhesive tape was peeled off after the UV irradiation, there was almost no residue on the adherend, and no stain occurred on the adherend.

  Adhesive tape No. Nos. 4 and 5 are cases where the pressure-sensitive adhesive composition does not contain the compound (C). Adhesive tape No. No. 6 is the case where the pressure-sensitive adhesive composition contains a copolymer having no structural unit (a-1). These adhesive tape Nos. Nos. 4 to 6 have low adhesive strength before UV irradiation, particularly low adhesive strength to a copper plate. Further, when the adhesive tape was peeled off after the UV irradiation, spots occurred on the adherend.

  Adhesive tape No. In Nos. 7 and 8, the pressure-sensitive adhesive composition contains a copolymer having a molecular weight distribution of more than 2.5. These adhesive tape Nos. In Nos. 7 and 8, when the adhesive tape was peeled off after UV irradiation, a large amount of residue remained on the adherend, and stains occurred on the adherend.

  The present invention includes the following embodiments.

Aspect 1
A base film, and an adhesive layer formed on at least one surface of the base film, wherein the adhesive layer comprises a (meth) acrylic copolymer (A), a crosslinking agent (B), The (meth) acrylic copolymer (A) is formed from a radiation-curable pressure-sensitive adhesive composition containing the compound (C), and the structural unit (a) represented by the following general formula (1) -1) and a structural unit (a-2) having a crosslinkable functional group, and the (meth) acrylic copolymer (A) has a weight average molecular weight of 200,000 to 2,000,000 and a molecular weight distribution ( PDI) is 2.5 or less, the compound (C) contains at least one compound selected from the group consisting of a rust inhibitor and a primary antioxidant, and the radiation-curable pressure-sensitive adhesive composition is The content of the radiation-polymerizable group in the solid content is 0.1 mmol / Adhesive tape, which is a ~10mmol / g.

［式（１）において、Ｒ¹¹は水素原子または置換基を有していてもよい鎖状もしくは環状の炭化水素基を示す。Ｒ¹²は置換基を有していてもよい鎖状もしくは環状の炭化水素基を示す。Ｒ¹¹およびＲ¹²が互いに結合して環状構造を形成していてもよい。Ｒ¹³は水素原子またはメチル基を示す。］

[In the formula (1), R ¹¹ represents a hydrogen atom or a linear or cyclic hydrocarbon group which may have a substituent. R ¹² represents a chain or cyclic hydrocarbon group which may have a substituent. R ¹¹ and R ¹² may combine with each other to form a cyclic structure. R ¹³ represents a hydrogen atom or a methyl group. ]

Aspect 2
The pressure-sensitive adhesive tape according to aspect 1, wherein the content of the structural unit (a-1) is 5% by mass to 40% by mass based on 100% by mass of the whole (meth) acrylic copolymer (A).

Aspect 3
The pressure-sensitive adhesive according to aspect 1 or 2, wherein the content of the structural unit (a-2) is 0.1% by mass to 10% by mass based on 100% by mass of the whole (meth) acrylic copolymer (A). tape.

Aspect 4
The pressure-sensitive adhesive tape according to any one of aspects 1 to 3, wherein the (meth) acrylic copolymer (A) is obtained by subjecting a monomer composition to living radical polymerization.

Aspect 5
The pressure-sensitive adhesive tape according to any one of aspects 1 to 4, wherein the compound (C) is a compound represented by the following general formula (4) and / or a compound represented by the following general formula (5).

［一般式（４）において、ｎは０〜４の整数を示す。Ｒ⁴¹は、炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数６〜１４のアリール基、カルボキシ基、炭素数２〜６のカルボキシアルキル基、−ＮＲ⁴¹¹Ｒ⁴¹²（Ｒ⁴¹¹およびＲ⁴¹²は、それぞれ独立して水素原子、炭素数１〜１０のアルキル基）、−ＳＯ₂ＮＨＲ⁴¹¹（Ｒ⁴¹¹は、炭素数１〜１０のアルキル基）、−Ｒ⁴¹³ＮＲ⁴¹¹Ｒ⁴¹²（Ｒ⁴¹¹およびＲ⁴¹²は、それぞれ独立して水素原子、炭素数１〜１０のアルキル基；Ｒ⁴¹³は炭素数１〜６のアルキレン基）、メルカプト基、ヒドロキシ基、ニトロ基、ハロゲン原子、炭素数１〜６のヒドロキシアルキル基、または炭素数１〜６のアルコキシカルボニル基を示す。ｎが２以上の場合、複数存在するＲ⁴¹は、同一でも異なっていてもよい。
Ｒ⁴²は、水素原子、炭素数１〜１２のアルキル基、炭素数１〜１２のアルコキシ基、炭素数６〜１４のアリール基、アミノ基、−ＮＲ⁴²¹Ｒ⁴²²（Ｒ⁴²¹およびＲ⁴²²は、それぞれ独立して水素原子、炭素数１〜１０のアルキル基）、−Ｒ⁴²³ＮＲ⁴²¹Ｒ⁴²²（Ｒ⁴²¹およびＲ⁴²²は、それぞれ独立して水素原子、炭素数１〜１０のアルキル基；Ｒ⁴²³は炭素数１〜６のアルキレン基）、メルカプト基、または、炭素数１〜１２のアルコキシカルボニル基示す。］

[In general formula (4), n shows the integer of 0-4. R ⁴¹ is an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an aryl group having 6 to 14 carbon atoms, a carboxy group, a carboxyalkyl group having 2 to 6 carbon atoms, —NR ⁴¹¹ R ⁴¹² ( R ⁴¹¹ and R ⁴¹² are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon ^{_{atoms), - SO 2 NHR 411 (}} R 411 represents an alkyl group having 1 to 10 carbon atoms), - R ⁴¹³ NR ⁴¹¹ R ⁴¹² (R ⁴¹¹ and R ⁴¹² are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms; R ⁴¹³ is an alkylene group having 1 to 6 carbon atoms), a mercapto group, a hydroxy group, a nitro group, a halogen atom, It represents a hydroxyalkyl group having 1 to 6 carbon atoms or an alkoxycarbonyl group having 1 to 6 carbon atoms. When n is 2 or more, a plurality of R ⁴¹ may be the same or different.
R ⁴² is a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 14 carbon atoms, an amino group, —NR ⁴²¹ R ⁴²² (R ⁴²¹ and R ⁴²² are Each independently represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms; -R ⁴²³ NR ⁴²¹ R ⁴²² (R ⁴²¹ and R ⁴²² each independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms; R ⁴²³ Represents an alkylene group having 1 to 6 carbon atoms), a mercapto group, or an alkoxycarbonyl group having 1 to 12 carbon atoms. ]

［一般式（５）において、Ｒ⁵¹は水素原子またはメチル基を示す。Ｒ⁵²およびＲ⁵³は、一方が水素原子、他方が１価の有機基を示す。Ｒ⁵⁴は１価の有機基を示す。］

[In the general formula (5), R ⁵¹ represents a hydrogen atom or a methyl group. One of R ⁵² and R ⁵³ represents a hydrogen atom, and the other represents a monovalent organic group. R ⁵⁴ represents a monovalent organic group. ]

Aspect 6
The radiation-curable pressure-sensitive adhesive composition further contains a radiation-polymerizable compound (D), wherein the radiation-polymerizable compound (D) has two or more radiopolymerizable groups in one molecule. An adhesive tape according to any one of the preceding claims.

Aspect 7
The pressure-sensitive adhesive tape according to embodiment 6, wherein the radiation-polymerizable compound (D) is a compound having 2 to 6 radiation-polymerizable groups in one molecule and having a weight average molecular weight of 100 to 30,000.

Aspect 8
The pressure-sensitive adhesive tape according to any one of aspects 1 to 7, wherein the crosslinking agent (B) is an isocyanate-based crosslinking agent.

Aspect 9
The pressure-sensitive adhesive tape according to any one of aspects 1 to 8, wherein a gel fraction of the pressure-sensitive adhesive layer is 20% by mass or more.

Aspect 10
The pressure-sensitive adhesive tape according to any one of aspects 1 to 9, which is used for semiconductor processing.

Aspect 11
A semiconductor wafer or a substrate and a ring frame, a sticking step of sticking the adhesive tape according to aspect 10, a dicing step of dicing the semiconductor wafer or the substrate into a semiconductor chip or a semiconductor component, and applying radiation to the adhesive tape. A semiconductor, comprising: an irradiating step of irradiating, an expanding step of extending the adhesive tape to widen a gap between the semiconductor chips or semiconductor components, and a pickup step of picking up a semiconductor chip or semiconductor component from the adhesive tape. Device manufacturing method.

  The pressure-sensitive adhesive tape of the present invention can be suitably used as a semiconductor processing tape such as a back grinding tape and a dicing tape, and can be preferably used as a dicing tape.

Claims (11)

A base film, having an adhesive layer formed on at least one surface of the base film,
The pressure-sensitive adhesive layer is formed from a radiation-curable pressure-sensitive adhesive composition containing a (meth) acrylic copolymer (A), a crosslinking agent (B), and a compound (C),
The (meth) acrylic copolymer (A) includes a structural unit (a-1) represented by the following general formula (1) and a structural unit (a-2) having a crosslinkable functional group, And the (meth) acrylic copolymer (A) has a weight average molecular weight of 200,000 to 2,000,000 and a molecular weight distribution (PDI) of 2.5 or less;
The compound (C) contains at least one compound selected from the group consisting of a rust inhibitor and a primary antioxidant;
A pressure-sensitive adhesive tape, wherein the content of the radiation-polymerizable group in the solid content of the radiation-curable pressure-sensitive adhesive composition is 0.1 mmol / g to 10 mmol / g.

[In the formula (1), R ¹¹ represents a hydrogen atom or a linear or cyclic hydrocarbon group which may have a substituent. R ¹² represents a chain or cyclic hydrocarbon group which may have a substituent. R ¹¹ and R ¹² may combine with each other to form a cyclic structure. R ¹³ represents a hydrogen atom or a methyl group. ]   The pressure-sensitive adhesive tape according to claim 1, wherein the content of the structural unit (a-1) is 5% by mass to 40% by mass based on 100% by mass of the whole (meth) acrylic copolymer (A).   3. The content according to claim 1, wherein the content of the structural unit (a-2) is 0.1% by mass to 10% by mass based on 100% by mass of the whole (meth) acrylic copolymer (A). 4. Adhesive tape.   The pressure-sensitive adhesive tape according to any one of claims 1 to 3, wherein the (meth) acrylic copolymer (A) is obtained by subjecting a monomer composition to living radical polymerization. The pressure-sensitive adhesive tape according to any one of claims 1 to 4, wherein the compound (C) is a compound represented by the following general formula (4) and / or a compound represented by the following general formula (5).

[In general formula (4), n shows the integer of 0-4. R ⁴¹ is an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an aryl group having 6 to 14 carbon atoms, a carboxy group, a carboxyalkyl group having 2 to 6 carbon atoms, —NR ⁴¹¹ R ⁴¹² ( R ⁴¹¹ and R ⁴¹² are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon ^{_{atoms), - SO 2 NHR 411 (}} R 411 represents an alkyl group having 1 to 10 carbon atoms), - R ⁴¹³ NR ⁴¹¹ R ⁴¹² (R ⁴¹¹ and R ⁴¹² are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms; R ⁴¹³ is an alkylene group having 1 to 6 carbon atoms), a mercapto group, a hydroxy group, a nitro group, a halogen atom, It represents a hydroxyalkyl group having 1 to 6 carbon atoms or an alkoxycarbonyl group having 1 to 6 carbon atoms. When n is 2 or more, a plurality of R ⁴¹ may be the same or different.
R ⁴² is a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 14 carbon atoms, an amino group, —NR ⁴²¹ R ⁴²² (R ⁴²¹ and R ⁴²² are Each independently represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms; -R ⁴²³ NR ⁴²¹ R ⁴²² (R ⁴²¹ and R ⁴²² each independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms; R ⁴²³ Represents an alkylene group having 1 to 6 carbon atoms), a mercapto group, or an alkoxycarbonyl group having 1 to 12 carbon atoms. ]

[In the general formula (5), R ⁵¹ represents a hydrogen atom or a methyl group. One of R ⁵² and R ⁵³ represents a hydrogen atom, and the other represents a monovalent organic group. R ⁵⁴ represents a monovalent organic group. ] The radiation-curable pressure-sensitive adhesive composition further contains a radiation-polymerizable compound (D),
The pressure-sensitive adhesive tape according to any one of claims 1 to 5, wherein the radiation-polymerizable compound (D) has two or more radiopolymerizable groups in one molecule.   The pressure-sensitive adhesive tape according to claim 6, wherein the radiation-polymerizable compound (D) is a compound having 2 to 6 radiation-polymerizable groups in one molecule and having a weight average molecular weight of 100 to 30,000.   The pressure-sensitive adhesive tape according to any one of claims 1 to 7, wherein the crosslinking agent (B) is an isocyanate-based crosslinking agent.   The pressure-sensitive adhesive tape according to any one of claims 1 to 8, wherein the pressure-sensitive adhesive layer has a gel fraction of 20% by mass or more.   The pressure-sensitive adhesive tape according to any one of claims 1 to 9, which is used for semiconductor processing. An attaching step of attaching the adhesive tape according to claim 10 to a semiconductor wafer or a substrate and a ring frame,
A dicing step of dicing the semiconductor wafer or substrate into a semiconductor chip or semiconductor component;
An irradiation step of irradiating the adhesive tape with radiation,
An expanding step of extending the adhesive tape to increase the distance between the semiconductor chips or semiconductor components,
A pickup step of picking up a semiconductor chip or a semiconductor component from the adhesive tape.