Adhesive composition and adhesive sheet

Abstract

This invention provides an adhesive composition comprising a (meth)acrylic resin, a photopolymerization initiator, and a crosslinking agent. The (meth)acrylic resin is a diblock copolymer composed of X-blocks and Y-blocks, wherein the molar ratio of the structural units of the X-blocks and Y-blocks is 40:60 to 95:5. The X-block comprises a structural unit having a hydroxyl group (M-1) and a structural unit having an olefinic unsaturated group (M-2). The Y-block comprises a component derived from an S-value of 20 (J / cm²). 3 ) 1 / 2 The structural unit (M-3) of the following olefinic unsaturated compound (m-3) has at least one of the structural units (M-1) to (M-3) having a structure derived from (meth)acryloyloxy. In the X block, the total proportion of structural unit (M-1) and structural unit (M-2) relative to the total of all structural units is 18 to 95 mol%, and in the Y block, the total proportion of structural unit (M-1) and structural unit (M-2) relative to the total of all structural units is 0 to 17 mol%.

Description

Technical Field

[0001] This disclosure relates to adhesive compositions using (meth)acrylic resins. It also relates to adhesive sheets, cutting tapes, and integrated cutting / chip bonding films having cured products of the aforementioned adhesive compositions as adhesive layers. Background Technology

[0002] Traditionally, blade dicing has been the primary method for manufacturing stacked semiconductor chips from semiconductor wafers made from materials such as silicon (Si) and gallium arsenide (GaAs). In this method, after surface-mount circuitry and back-side grinding, the semiconductor wafer is attached to a dicing tape. During the dicing process, a high-speed rotating blade cuts and separates the wafer into tiny semiconductor chips. After cleaning, the diced wafer is then fed to a pick-up process. In this pick-up process, the adhesive layer of the dicing tape is first irradiated with energy rays such as ultraviolet light to cure the adhesive layer, thereby reducing adhesion. The dicing tape is then expanded and lifted from the back side using a pin, and the semiconductor chip is picked up by vacuum suction.

[0003] In blade cutting, cutting is often performed while water is supplied to the blade to cool it and remove chips as it heats up during the cutting process. If the water seeps between the cutting tape and the semiconductor wafer, the adhesion is significantly reduced, thus requiring the cutting tape to have excellent water resistance.

[0004] As a cutting tape with excellent water resistance, for example, Patent Document 1 (Japanese Patent Application Publication No. 2012-216841) proposes a cutting tape in which an adhesive layer is formed on a substrate resin film. The adhesive layer is formed by adding polypropylene oxide with a specific number average molecular weight to an acrylic polymer with radiopolymerizable carbon-carbon double bonds in the molecule and a photopolymerization initiator.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2012-216841 Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] Cutting tapes used in the cutting process are primarily made by coating a resin film substrate with adhesives such as acrylic adhesives to form an adhesive layer. As cutting tapes, they support semiconductor wafers and prevent the cut semiconductor chips from scattering during cutting. In recent years, with the miniaturization of semiconductor chips, the area on the cutting tape supporting a single semiconductor chip has decreased. Therefore, there is a need to improve the adhesive strength of the cutting tape. Furthermore, with the miniaturization of semiconductor chips, higher levels of water resistance are also required. However, the cutting tape proposed in Patent Document 1 has low adhesive strength, which is insufficient for supporting microchips.

[0010] This disclosure provides an adhesive composition that provides an adhesive sheet with excellent water resistance and sufficient adhesion to the adherend, and excellent peelability after UV irradiation. Furthermore, this disclosure relates to adhesive sheets, cutting tapes, and integrated cutting / chip bonding films having a cured product of the above adhesive composition as an adhesive layer. More specifically, it provides cutting tapes and integrated cutting / chip bonding films with excellent water resistance, good cutability, and excellent pick-up properties after UV irradiation.

[0011] Problem-solving methods

[0012] The contents of this disclosure include the following schemes.

[0013] [1] An adhesive composition comprising (meth)acrylic resin (A), a photopolymerization initiator (B), and a crosslinking agent (C);

[0014] The (meth)acrylic resin (A) is a diblock copolymer composed of X-blocks and Y-blocks.

[0015] The structural unit ratio (molar ratio) of the X-block and the Y-block is 40:60 to 95:5.

[0016] The X block comprises a structural unit having a hydroxyl group (M-1) and a structural unit having an olefinic unsaturated group (M-2).

[0017] The Y-block contains elements originating from an SP value of 20 (J / cm). 3 ) 1 / 2 The structural unit (M-3) of the following olefinic unsaturated compound (m-3), and optionally one or more structural units selected from structural units having hydroxyl groups (M-1) and structural units having olefinic unsaturated groups (M-2),

[0018] At least one of the structural units (M-1), (M-2), and (M-3) has a structure derived from (meth)acryloyloxy.

[0019] When the total number of structural units in the X block is set to 100 mol%, the total proportion of the structural units with hydroxyl groups (M-1) and the structural units with olefinic unsaturated groups (M-2) in the X block is 18–95 mol%.

[0020] When the total number of structural units in the Y-block is set to 100 mol%, the total proportion of the structural units with hydroxyl groups (M-1) and the structural units with olefinic unsaturated groups (M-2) in the Y-block is 0 to 17 mol.

[0021] [2] According to the adhesive composition of [1], when the total number of structural units of the X block is set to 100 mol%, the proportion of the structural unit (M-2) having an olefinic unsaturated group in the X block is 1 to 60 mol%.

[0022] [3] According to the adhesive composition of [1] or [2], when the total number of structural units of the X block is set to 100 mol%, the proportion of the hydroxyl-containing structural unit (M-1) in the X block is 0.1 to 35 mol%.

[0023] [4] In any one of the adhesive compositions according to [1] to [3], the structural unit (M-2) having an olefinic unsaturated group in the X block is a structural unit formed by adding an isocyanate-containing olefinic unsaturated compound (a) to the hydroxyl group of a structural unit derived from an olefinic unsaturated compound (m-1) having a hydroxyl group.

[0024] [5] In the adhesive composition according to any one of [1] to [4], when the total number of structural units of the Y-block is set to 100 mol%, the Y-block has a source SP value of 20 (J / cm). 3 ) 1 / 2 The following olefinic unsaturated compounds (m-3) have a structural unit (M-3) proportion of 70 mol% or more.

[0025] [6] The adhesive composition according to any one of [1] to [5], wherein the Y-block has a source SP value of 20 (J / cm). 3 ) 1 / 2 The structural unit (M-3) of the following olefinic unsaturated compounds (m-3) is derived from the structural unit of a straight-chain or branched (meth)acrylate ester with 6 to 30 carbon atoms selected from alkyl groups, (meth)acrylate esters containing an alicyclic skeleton, and styrene monomers.

[0026] [7] The adhesive composition according to any one of [1] to [6], wherein the Y block has a structural unit derived from styrene.

[0027] [8] In any one of the adhesive compositions according to [1] to [7], the X block further has a structural unit of a straight-chain or branched (meth)acrylate alkyl ester having 1 to 6 carbon atoms derived from an alkyl group.

[0028] [9] The adhesive composition according to any one of [1] to [8], wherein the weight-average molecular weight of the (meth)acrylic resin (A) is 1 × 10⁻⁶. 4 ~200×10 4 .

[0029]

[10] The adhesive composition according to any one of [1] to [9] has an olefinic unsaturated group equivalent of 100 to 5000 g / mol in the (meth)acrylic resin (A).

[0030]

[11] The adhesive composition according to any one of [1] to

[10] , wherein the hydroxyl value of the (meth)acrylic resin (A) is 0.01 to 50 mg KOH / g.

[0031]

[12] An adhesive sheet having a substrate layer and an adhesive layer formed of a thermocurable or photothermal curable adhesive composition of any one of [1] to

[11] .

[0032]

[13] A cutting tape having a substrate layer and an adhesive layer formed of a thermosetting or photothermal curing material of an adhesive composition described in any one of [1] to

[11] .

[0033]

[14] A dicing / chip bonding integrated film, comprising in sequence a substrate layer, an adhesive layer formed of a thermosetting or photothermal curing material of an adhesive composition as described in any one of [1] to

[11] , and an adhesive layer.

[0034] Invention Effects

[0035] According to this disclosure, an adhesive composition can be provided that provides an adhesive sheet with high adhesion and excellent water resistance, and whose adhesion significantly decreases after UV irradiation. According to this disclosure, adhesive sheets, dicing tapes, and dicing / chip bonding integrated films having a cured product of the above-described adhesive composition as an adhesive layer can be provided. According to this disclosure, adhesive sheets with excellent water resistance and sufficient adhesion to the adhered objects, and excellent peelability after UV irradiation can be provided. Additionally, dicing tapes and dicing / chip bonding integrated films can be provided that can suppress the scattering of tiny semiconductor chips and easily pick up semiconductor chips after UV irradiation. Detailed Implementation

[0036] The embodiments of the present invention will now be described in detail. However, the present invention is not limited to the embodiments shown below.

[0037] In this specification, when "~" is used to indicate a numerical range, the values ​​at both ends are the upper and lower limits, respectively, and are included within the numerical range. When multiple upper or lower limits are specified, the numerical range can be formed by any combination of the upper and lower limits. Similarly, when multiple numerical ranges are specified, a separate numerical range can be formed by selecting and combining the upper and lower limits from these ranges.

[0038] In this specification, "(meth)acrylic acid" refers to methacrylic acid or acrylic acid, "(meth)acrylate" refers to acrylate or methacrylate, and "(meth)acryloyloxy" refers to acryloyloxy or methacryloyloxy.

[0039] In this specification, "structural unit" refers to a unit derived from a polymeric compound used as a monomer or a unit obtained by further modifying a unit derived from a polymeric compound used as a monomer.

[0040] In this specification, "photocrosslinkable adhesive" refers to a thermosetting adhesive composition that exhibits photocrosslinking properties in its thermosetting state. Photocrosslinkable adhesives can be crosslinked by ultraviolet radiation.

[0041] In this specification, "photothermal cured material" refers to a substance formed by cross-linking the above-mentioned photocrosslinking adhesive through ultraviolet irradiation.

[0042] In this specification, "weight-average molecular weight (Mw)" and "number-average molecular weight (Mn)" are values ​​determined by gel permeation chromatography (GPC) under the following conditions and at room temperature (23°C), and obtained using a standard polystyrene standard curve.

[0043] Device: Shodex (trademark) GPC-101 (RESONAC Co., Ltd.)

[0044] Pillar: Shodex (trademark) LF-804 (RESONAC Co., Ltd.)

[0045] Column temperature: 40℃

[0046] Sample: 0.2% by mass tetrahydrofuran solution of the sample

[0047] Flow rate: 1 mL / min

[0048] Eluent: Tetrahydrofuran

[0049] Detector: Shodex RI-71S (RESONAC Co., Ltd.)

[0050] In this specification, "glass transition temperature (Tg)" refers to the endothermic onset temperature based on the glass transition, measured by differential scanning calorimetry (DSC) at a rate of 10°C / min, changing the temperature of the sample from -100°C to 200°C. If more than two endothermic onset temperatures are observed, Tg is the simple average of these two or more endothermic onset temperatures.

[0051] [Adhesive Composition]

[0052] The adhesive composition contains (meth)acrylic resin (A), a photopolymerization initiator (B), a crosslinking agent (C), and other components added as needed. The adhesive composition containing (meth)acrylic resin (A) is suitable for use in re-peelable adhesive sheets, particularly for cut tapes and cut / chip bonding integrated films.

[0053] <(Meth)acrylic resin (A)>

[0054] (Meth)acrylic resin (A) is a diblock copolymer composed of X-blocks and Y-blocks. (Meth)acrylic resin (A) has at least one structure derived from (meth)acryloyloxy groups. The molar ratio of the structural units of the X-block to the Y-block is 40:60 to 95:5. When a group of raw monomers containing monomers that contribute to adhesion and monomers that contribute to water resistance is subjected to free radical polymerization, the properties of the monomers in the resulting copolymer are averaged out, making it difficult to fully utilize the characteristics of each monomer type. To better utilize the characteristics of each monomer type, the inventors investigated copolymers having multiple blocks containing specific structural units. The results showed that diblock copolymers composed of two blocks containing specific structural units can provide adhesive compositions with excellent water resistance and adhesion.

[0055] The ratio of the structural units of the X-block to all structural units of the (meth)acrylic resin (A) is 40 mol% or more, preferably 50 mol% or more, and more preferably 55 mol% or more. The ratio of the structural units of the X-block to all structural units of the (meth)acrylic resin (A) is 95 mol% or less, preferably 90 mol% or less, and more preferably 85 mol% or less. Any combination of these lower and upper limits is permissible. When the ratio of the structural units of the X-block is 40 mol% or more, sufficient adhesive force is achieved to the adhered object. Therefore, when used as a cutting tape or a cutting / chip bonding integrated film, sufficient cutability is achieved. When the ratio of the structural units of the X-block is 95 mol% or less, sufficient water resistance is achieved to the adhered object. Therefore, when used as a cutting tape or a cutting / chip bonding integrated film, sufficient adhesive force is achieved in processes involving water such as cutting water.

[0056] The ratio of the Y-block structural units to all structural units of the (meth)acrylic resin (A) is 5 mol% or more, preferably 10 mol% or more, and more preferably 15 mol% or more. The ratio of the Y-block structural units to all structural units of the (meth)acrylic resin (A) is 60 mol% or less, preferably 50 mol% or less, and more preferably 45 mol% or less. Any combination of these lower and upper limits is permissible. When the ratio of the Y-block structural units is 5 mol% or more, sufficient water resistance of the adhesive layer to the adhered object is achieved. Therefore, when used as a cutting tape or a cutting / chip bonding integrated film, sufficient adhesive strength is achieved in processes involving water such as cutting water. When the ratio of the Y-block structural units is 60 mol% or less, sufficient adhesive strength of the adhesive layer to the adhered object is achieved. Therefore, when used as a cutting tape or a cutting / chip bonding integrated film, sufficient cutability is achieved.

[0057] The X-block comprises a structural unit (M-1) having a hydroxyl group (also referred to as structural unit (M-1)) and a structural unit (M-2) having an olefinic unsaturated group (also referred to as structural unit (M-2)). The X-block also comprises other structural units (M-4) besides structural units (M-1) and (M-2) (also referred to as structural units (M-4)). When the total number of structural units in the X-block is set to 100 mol%, the total proportion of the hydroxyl-containing structural unit (M-1) and the olefinic unsaturated structural unit (M-2) in the X-block is 18 mol% or more, preferably 19 mol% or more, more preferably 20 mol% or more. When the total number of structural units in the X-block is set to 100 mol%, the total proportion of the hydroxyl-containing structural unit (M-1) and the olefinic unsaturated structural unit (M-2) in the X-block is 95 mol% or less, preferably 60 mol% or less, more preferably 40 mol% or less. These lower and upper limits can be combined in any way.

[0058] The Y segment contains information originating from an SP value of 20 (J / cm). 3 ) 1 / 2The structural unit of the following olefinic unsaturated compound (m-3) (also called compound (m-3)) and the structural unit (M-3) (also called structural unit (M-3)) that does not have olefinic unsaturated groups and hydroxyl groups. The Y-block may, as needed, include structural units selected from structural units having hydroxyl groups (M-1), structural units having olefinic unsaturated groups (M-2), and other structural units (M-5) other than structural units (M-1) to (M-3) (also referred to as structural units other than structural unit (M-3)). When the total number of structural units in the Y-block is set to 100 mol%, the total proportion of structural units having hydroxyl groups (M-1) and structural units having olefinic unsaturated groups (M-2) included in the Y-block is 0 mol% or more, which may be 3 mol% or more, or 5 mol% or more. When the total number of structural units in the Y-block is considered to be 100 mol%, the total proportion of structural units having hydroxyl groups (M-1) and structural units having olefinic unsaturated groups (M-2) included in the Y-block is 17 mol% or less, preferably 15 mol% or less, more preferably 10 mol% or less. The combination of these lower and upper limits can be arbitrary.

[0059] By including (meth)acrylic resin (A) in the adhesive composition, sufficient adhesion to the substrate is obtained mainly through the contribution of the X block, and excellent peelability from the substrate is obtained after UV irradiation. By including (meth)acrylic resin (A) in the adhesive composition, a water-resistant adhesive sheet is obtained mainly through the contribution of the Y block. Therefore, when the adhesive composition containing (meth)acrylic resin (A) is used in cutting tapes with adhesive layers and cutting / chip bonding integrated films, it exhibits excellent water resistance in processes using water such as cutting water, good cutting performance, and excellent pick-up performance of monolithic semiconductor chips after UV irradiation.

[0060] The weight-average molecular weight (Mw) of the (meth)acrylic resin (A) is preferably 1 × 10⁻⁶. 4 The above is preferred to be 3×10 4 The above is further preferred to be 10×10 4 The above. The weight-average molecular weight (Mw) of the (meth)acrylic resin (A) is preferably 200 × 10⁻⁶. 4 Hereinafter, 150×10 is preferred. 4 Hereinafter, 100×10 is further preferred. 4 The following are the lower and upper limits. These lower and upper limits can be combined in any way. The weight-average molecular weight (Mw) is 1 × 10⁻⁶. 4 When the adhesive composition is cured as described above, the resulting adhesive sheet exhibits good adhesion, and when used as a cutting tape or a cutting / chip bonding integrated film, it demonstrates good cutability. The weight-average molecular weight (Mw) is 200 × 10⁻⁶. 4The adhesive layer exhibits sufficient peelability after UV irradiation, resulting in good pick-up performance when the adhesive sheet is used as a cutting tape or a cutting / chip bonding integrated film. Furthermore, the adhesive layer achieves sufficient strength to prevent contamination of the adhered material during peeling. Additionally, the viscosity of the adhesive composition can be controlled within an appropriate range, ensuring operability when coating it onto a substrate to produce the adhesive sheet and achieving a uniform film thickness.

[0061] The molecular weight distribution (Mw / Mn) of the (meth)acrylic resin (A) can be 1.1 or more, 1.3 or more, or 1.5 or more. The molecular weight distribution (Mw / Mn) of the (meth)acrylic resin (A) is preferably 5.0 or less, more preferably 4.5 or less, and even more preferably 4.0 or less. Any combination of these lower and upper limits is acceptable. When the molecular weight distribution is 1.1 or more, the manufacturing conditions are easier to control. When the molecular weight distribution is 5.0 or less, a better adhesive composition can be obtained compared to synthesis via free radical polymerization without controlling the molecular weight distribution. That is, by narrowing the molecular weight distribution, the influence of the low molecular weight portion of the (meth)acrylic resin (A) on the cutability, pick-up ability, and contamination of the adhered material of the adhesive sheet can be reduced. On the other hand, the influence of the high molecular weight portion of the (meth)acrylic resin (A) on the viscosity control of the adhesive composition can be reduced, and the adhesive sheet performance can be stably obtained.

[0062] The olefin unsaturated group equivalent of the (meth)acrylic resin (A) is preferably 100 g / mol or more, more preferably 250 g / mol or more, and even more preferably 500 g / mol or more. The olefin unsaturated group equivalent of the (meth)acrylic resin (A) is preferably 5000 g / mol or less, more preferably 3000 g / mol or less, and even more preferably 2000 g / mol or less. Any combination of these lower and upper limits is permissible. When the olefin unsaturated group equivalent of the (meth)acrylic resin (A) is 100 g / mol or more, its compatibility with conventional organic solvents improves. When the olefin unsaturated group equivalent of the (meth)acrylic resin (A) is 5000 g / mol or less, the adhesive layer exhibits sufficient peelability after UV irradiation, and good pick-up performance is achieved when the adhesive sheet is used as a cutting tape or a cutting / chip bonding integrated film.

[0063] In this specification, the equivalent of olefinic unsaturated groups in (meth)acrylic resin (A) refers to the mass of (meth)acrylic resin (A) corresponding to 1 mole of olefinic unsaturated bonds. In one embodiment, the equivalent of olefinic unsaturated groups in (meth)acrylic resin (A) is a calculated value based on the amount of raw materials used in the manufacture of (meth)acrylic resin (A), assuming 100% reaction of all raw materials. The equivalent of olefinic unsaturated groups in (meth)acrylic resin (A) can be calculated from the amount of halogen bonded to (meth)acrylic resin (A). The amount of halogen bonded to (meth)acrylic resin (A) can be evaluated according to JIS K 0070:1992.

[0064] The glass transition temperature (Tg) of the (meth)acrylic resin (A) is preferably -80°C to 0°C, more preferably -70°C to -10°C, and even more preferably -65°C to -20°C. If the glass transition temperature is above -80°C, the pickup properties are good. If the glass transition temperature is below 0°C, the adhesion before UV irradiation is good.

[0065] The hydroxyl value of the (meth)acrylic resin (A) is preferably 0.01 mg KOH / g or more, more preferably 2.5 mg KOH / g or more, and even more preferably 5 mg KOH / g or more. The hydroxyl value of the (meth)acrylic resin (A) is preferably 50 mg KOH / g or less, more preferably 30 mg KOH / g or less, and even more preferably 15 mg KOH / g or less. Any combination of these lower and upper limits is permissible. When the hydroxyl value of the (meth)acrylic resin (A) is 0.01 mg KOH / g or more, the resin can be sufficiently thermocured through a heat-based crosslinking reaction, resulting in a good adhesive strength in the resulting adhesive sheet. Therefore, when the adhesive sheet is used as a cutting tape or a cutting / chip bonding integrated film, it exhibits good cutability. Furthermore, the adhesive layer can obtain sufficient strength, preventing contamination of the adhered material when peeling off the adhesive sheet. When the hydroxyl value of the (meth)acrylic resin (A) is 50 mg KOH / g or less, the amount of hydroxyl groups in the thermocured adhesive layer is sufficiently reduced, resulting in good water resistance in the resulting adhesive sheet. Therefore, when adhesive sheets are used as cutting tapes or cutting / chip bonding films, they also exhibit excellent water resistance and improved cutting performance in processes involving water, such as cutting water.

[0066] In this specification, the hydroxyl value of (meth)acrylic resin (A) is determined according to JIS K0070:1992 using a mixture of bromothymol blue and phenol red indicators. The hydroxyl value of the resin refers to the mass (mg) of potassium hydroxide required to neutralize the acetic acid bonded to the hydroxyl group when 1g of the resin is acetylated.

[0067] (X block of (meth)acrylic resin (A))

[0068] The X block of the (meth)acrylic resin (A) comprises a structural unit having a hydroxyl group (M-1) and a structural unit having an olefinic unsaturated group (M-2). The X block also comprises other structural units (M-4) besides structural units (M-1 and M-2).

[0069] "Structural unit with hydroxyl group (M-1)"

[0070] The structural unit (M-1) is a structural unit that has a hydroxyl group but no olefinic unsaturated group. The structural unit (M-1) is preferably a structural unit derived from a compound having both a hydroxyl group and a (meth)acryloyloxy group. By incorporating the (meth)acrylic resin (A) with the structural unit (M-1), an adhesive sheet with sufficient adhesive strength can be obtained. Furthermore, the crosslinking points with the crosslinking agent (C) described later can be ensured, improving the strength of the adhesive layer. The structural unit (M-1) can be only one type or can be two or more types.

[0071] When the total number of structural units in the X-block of the (meth)acrylic resin (A) is set to 100 mol%, the content of structural unit (M-1) in the X-block is preferably 0.1 mol% or more, more preferably 1 mol% or more, and even more preferably 1.5 mol% or more. When the total number of structural units in the X-block of the (meth)acrylic resin (A) is set to 100 mol%, the content of structural unit (M-1) in the X-block is preferably 35 mol% or less, more preferably 20 mol% or less, and even more preferably 10 mol% or less. Any combination of these lower and upper limits is permissible. When the content of structural unit (M-1) in the X-block is 0.1 mol% or more, the resin can be sufficiently thermocured through a heat-based crosslinking reaction. Furthermore, the resulting adhesive sheet exhibits good adhesion, and when used as a cutting tape or a cutting / chip bonding integrated film, it demonstrates good cutability. Moreover, the adhesive layer acquires sufficient strength, preventing contamination of the adhered material during peeling of the adhesive sheet. When the content of structural unit (M-1) in the X block is less than 35 mol%, the amount of hydroxyl groups in the thermosetting adhesive layer is sufficiently reduced, resulting in good water resistance of the adhesive sheet. Therefore, when the adhesive sheet is used as a cutting tape or a cutting / chip bonding integrated film, it also exhibits excellent water resistance and improved cutting performance in processes involving water such as cutting water.

[0072] The structural unit (M-1) is derived from the structural unit of an olefinic unsaturated compound (m-1) containing a hydroxyl group (also called compound (m-1)). For olefinic unsaturated compounds (m-1) containing a hydroxyl group, there are no particular restrictions as long as the compound has a hydroxyl group and an olefinic unsaturated group. Specifically, examples include hydroxyalkyl methacrylates such as 2-hydroxyethyl methacrylate, 3-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, 2,3-dihydroxypropyl methacrylate, and 4-hydroxybutyl methacrylate; hydroxyphenyl methacrylate and 2-hydroxy-3-phenoxypropyl methacrylate, which are methacrylates containing both an aromatic ring and a hydroxyl group; and hydroxystyrene, etc. In terms of curability when combined with the crosslinking agent (C) described later, hydroxyalkyl methacrylate is preferred, more preferably hydroxyalkyl methacrylate with 1 to 6 carbon atoms in the hydroxyalkyl group, and even more preferably hydroxyalkyl methacrylate with hydroxyl groups at the end of the straight-chain alkyl group. Particularly preferred are 2-hydroxyethyl methacrylate, 3-hydroxypropyl methacrylate and 4-hydroxybutyl methacrylate.

[0073] "Structural Units with Alkenyl Unsaturated Groups (M-2)"

[0074] The structural unit (M-2) is a structural unit having an olefinic unsaturated group. The structural unit (M-2) is preferably derived from a (meth)acrylate (m-2) having an olefinic unsaturated group other than (meth)acryloyloxy, as described later, or a structural unit of a compound having an olefinic unsaturated group other than (meth)acryloyloxy but having a (meth)acryloyloxy group. By incorporating the structural unit (M-2) into the (meth)acrylate resin (A), after an adhesive sheet having an adhesive layer using the (meth)acrylate resin (A) is adhered to an adhesive substrate, the adhesive strength is reduced by UV irradiation, allowing for easy peeling from the substrate. When the adhesive sheet is used as a cutting tape or a cutting / chip bonding integrated film, it exhibits good cutability and excellent pick-up performance after UV irradiation. The structural unit (M-2) can be only one type or can be two or more types.

[0075] When the total number of structural units in the X-block of the (meth)acrylic resin (A) is set to 100 mol%, the content of structural unit (M-2) in the X-block is preferably 1 mol% or more, more preferably 8 mol% or more, and even more preferably 15 mol% or more. When the total number of structural units in the X-block of the (meth)acrylic resin (A) is set to 100 mol%, the content of structural unit (M-2) in the X-block is preferably 60 mol% or less, more preferably 40 mol% or less, and even more preferably 30 mol% or less. These lower and upper limits can be combined arbitrarily. When the content of structural unit (M-2) in the X-block is 1 mol% or more, sufficient peelability can be obtained after irradiating the adhesive sheet with ultraviolet light, and good pick-up performance can be obtained when the adhesive sheet is used as a cutting tape or a cutting / chip bonding integrated film. When the content of structural unit (M-2) in the X-block is 60 mol% or less, compatibility with conventional organic solvents improves.

[0076] In one embodiment, the structural unit (M-2) is a structural unit derived from an olefinic unsaturated group other than (meth)acryloyloxy (m-2) (also referred to as compound (m-2)). Examples of compounds (m-2) include vinyl methacrylate, allyl methacrylate, isopropylene methacrylate, 2-butenyl methacrylate, and other alkenyl methacrylates; and dicyclopentenyl methacrylate, dicyclopentenyl methacrylate, and other alkenyl methacrylates containing an unsaturated alicyclic skeleton. From the perspective of reaction control, alkenyl methacrylates are preferred, allyl methacrylate, isopropylene methacrylate, and 2-butenyl methacrylate are more preferred, and isopropylene methacrylate is even more preferred.

[0077] In one embodiment, the structural unit (M-2) is a structural unit formed by adding an isocyanate group of an olefinic unsaturated compound (a) containing an isocyanate group to a hydroxyl group derived from a structural unit of an olefinic unsaturated compound (m-1) having a hydroxyl group. Specifically, there are no particular limitations on the aforementioned olefinic unsaturated compound (a) containing an isocyanate group, as long as it does not have a hydroxyl group but has an isocyanate group and an olefinic unsaturated group. Specifically, examples include ethyl isocyanate 2-methacrylic acid, propyl isocyanate 2-methacrylic acid, propyl isocyanate 3-methacrylic acid, methyl ethyl isocyanate 2-methacrylic acid, 1,1-dimethyl ethyl isocyanate 2-methacrylic acid, cyclohexyl isocyanate 4-methacrylic acid, and other methacryloyloxyalkyl isocyanates; ethyl (2-isocyanate ethoxy)methacrylic acid; and 1,1-(bis(methacryloyloxymethyl)ethyl isocyanate. Among these, considering the ease of synthesis of methacrylic resin (A), alkyl isocyanates are preferred, and 2-(methacryloyloxyethyl) isocyanate is more preferred.

[0078] When a structural unit (M-2) is introduced into the (meth)acrylic acid copolymer by adding an isocyanate-containing olefinic unsaturated compound (a) to a portion of the hydroxyl groups of the structural unit derived from the hydroxyl-containing olefinic unsaturated compound (m-1), the addition rate of the isocyanate-containing olefinic unsaturated compound (a) relative to the molar number of hydroxyl groups is preferably 40 mol% or more, more preferably 60 mol% or more, and even more preferably 80 mol% or more. The addition rate of the isocyanate-containing olefinic unsaturated compound (a) is preferably 99 mol% or less, more preferably 98 mol% or less, and even more preferably 95 mol% or less. Any combination of these lower and upper limits is permissible. When the addition rate of the isocyanate-containing olefinic unsaturated compound (a) is 40 mol% or more, sufficient peelability is obtained after irradiating the adhesive sheet with ultraviolet light, and good pick-up performance is obtained when the adhesive sheet is used as a cutting tape or a cutting / chip bonding integrated film. If the addition rate of the olefinic unsaturated compound (a) containing isocyanate groups is less than 99 mol%, the resin can be sufficiently thermocured through a heat-based crosslinking reaction. Furthermore, the resulting adhesive sheet exhibits good adhesion. Therefore, when used as a cutting tape or a cutting / chip bonding integrated film, the adhesive sheet demonstrates good cutability. Moreover, the adhesive layer achieves sufficient strength, preventing contamination of the adhered material during peeling of the adhesive sheet.

[0079] Other Structural Units

[0080] The X block of (meth)acrylic resin (A) also includes structural units (M-4) other than structural units (M-1) and (M-2). Structural units (M-4) can be only one type or two or more types.

[0081] When the total structural units of the X block of the (meth)acrylic resin (A) are set to 100 mol%, the content of other structural units (M-4) in the X block is 5 mol% or more, preferably 25 mol% or more, and more preferably 50 mol% or more. When the total structural units of the X block of the (meth)acrylic resin (A) are set to 100 mol%, the content of other structural units (M-4) in the X block is 82 mol% or less, preferably 78 mol% or less, more preferably 75 mol% or less, and even more preferably 70 mol% or less. These lower and upper limits can be combined arbitrarily. When the content of other structural units (M-4) in the X block is 5 mol% or more, the resulting adhesive sheet exhibits good adhesion. Therefore, when the adhesive sheet is used as a cutting tape or a cutting / chip bonding integrated film, it exhibits good cutability. When the content of other structural units (M-4) in the X block is less than 82 mol%, the (meth)acrylic resin (A) contains sufficient hydroxyl and olefinic unsaturated groups, resulting in good thermosetting properties and reduced adhesion due to UV irradiation. Therefore, when the adhesive sheet is used as a cutting tape or a cutting / chip bonding integrated film, its cutability and pick-up performance improve.

[0082] As compounds that provide other structural units (M-4), examples include monomers other than compounds (m-1) and (m-2) that can copolymerize with compounds (m-1) and (m-2). Specific examples include alkyl methacrylates; carboxyl-containing monomers; dienes such as butadiene and dicyclopentadiene; styrene derivatives; unsaturated dicarboxylic acid diesters; and other vinyl compounds.

[0083] Examples of alkyl methacrylates include linear or branched alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, tert-butyl methacrylate, pentyl methacrylate, neopentyl methacrylate, 2-ethylhexyl methacrylate, isoamyl methacrylate, and dodecyl methacrylate; and cyclopentyl methacrylate, cyclohexyl methacrylate, ethylcyclohexyl methacrylate, norbornyl methacrylate, dicyclopentyl methacrylate, isobornyl methacrylate, and adamantyl methacrylate. From a reactivity perspective, linear or branched alkyl methacrylates with 1 to 5 carbon atoms in the alkyl group are preferred, as are cyclohexyl methacrylates, and at least n-butyl methacrylate is more preferred.

[0084] Examples of carboxyl-containing monomers include (meth)acrylic acid, crotonic acid, vinylbenzoic acid, unsaturated monocarboxylic acids such as α-haloalkyl, alkoxy, halogen, nitro, or cyano-substituted derivatives of acrylic acid, and unsaturated dicarboxylic acids such as itaconic acid. Among these, (meth)acrylic acid is preferred from the perspective of ease of manufacturing the adhesive layer.

[0085] Specific examples of styrene include styrene, and α-, ☐-, ☐-, or ☐-alkyl derivatives of styrene.

[0086] Specific examples of unsaturated dicarboxylic acid diesters include diethyl citrate, diethyl maleate, diethyl fumarate, and diethyl itaconic acid.

[0087] Specific examples of other vinyl compounds include norbornene (bicyclo[2.2.1]hept-2-ene), 5-methylbicyclo[2.2.1]hept-2-ene, 5-ethylbicyclo[2.2.1]hept-2-ene, and tetracyclo[4.4.0.1]. 2,5 .1 7,10 [Dodecyl-3-ene, 8-methyltetracyclo[4.4.0.1]] 2,5 .1 7,10 [Dodecyl-3-ene, 8-ethyltetracyclo[4.4.0.1]] 2,5 .1 7,10 [Dodecyl-3-ene, tricyclic [5.2.1.0]] 2,6 ] Dec-8-ene, tricyclic [5.2.1.0 2,6 ] Dec-3-ene, tricyclic [4.4.0.1 2,5 Undec-3-ene, tricyclic [6.2.1.0] 1,8 Undec-9-ene, tricyclic [6.2.1.0] 1,8Undec-4-ene, tetracyclo[4.4.0.1] 2,5 .1 7,10 .0 1 ,6 [Dodecyl-3-ene, 8-methyltetracyclo[4.4.0.1]] 2,5 .1 7,10 .0 1,6 [Dodecyl-3-ene, 8-ethylidene tetracyclo[4.4.0.1]] 2 ,5 .1 7,10 [Dodecyl-3-ene, 8-ethylidene tetracyclo[4.4.0.1]] 2,5 .1 7,10 .0 1,6 [Dodecyl-3-ene, pentacyclic [6.5.1.1]] 3 ,6 .0 2,7 .0 9,13 Pentadecyl-4-ene, pentacyclic [7.4.0.1] 2,5 .1 9,12 .0 8,13 Pentadec-3-ene, (meth)acrylanilide, vinylpyridine, vinyl acetate, etc.

[0088] From the perspective of reaction control, alkyl (meth)acrylates are preferred, and alkyl (meth)acrylates with a straight chain or branched chain having 1 to 5 carbon atoms in the alkyl group are more preferred.

[0089] <Y-block of (meth)acrylic resin (A)>

[0090] The Y block of (meth)acrylic resin (A) contains components derived from an SP value of 20 (J / cm). 3 ) 1 / 2 The following olefin unsaturated compound (m-3) has a structural unit (M-3). For the above Y block, it may, as needed, include structural units other than structural units (M-3) other than structural units (M-1) having a hydroxyl group, structural units (M-2) having an olefin unsaturated group, and structural units (M-5) other than structural units (M-1) to (M-3).

[0091] The source is an SP value of 20 (J / cm). 3 ) 1 / 2 The following structural unit (M-3) of olefinic unsaturated compounds (m-3)

[0092] Structural unit (M-3) is a structural unit that does not have olefinic unsaturated groups and hydroxyl groups, and is derived from an SP value of 20 (J / cm). 3 ) 1 / 2The following are structural units of olefinic unsaturated compounds (m-3). Structural units (M-3) are preferably derived from an SP value of 20 (J / cm). 3 ) 1 / 2 The following are structural units of compounds containing (meth)acryloyloxy groups. Structural unit (M-3) can be only one type or two or more types.

[0093] In this specification, the SP value refers to the solubility parameter value (δTot) calculated using a program such as HSP (Hansen Solubility Parameters in Practice). δTot represents the magnitude of the HSP vector. By incorporating structural units (M-3) into the (meth)acrylic resin (A), adhesive sheets with good water resistance can be obtained.

[0094] When the total number of structural units in the Y-block of the (meth)acrylic resin (A) is set to 100 mol%, the content of structural unit (M-3) in the Y-block can be 50 mol% or more, 60 mol% or more, 70 mol% or more, or 80 mol% or more. When the total number of structural units in the Y-block of the (meth)acrylic resin (A) is considered to be 100 mol%, the content of structural unit (M-3) in the Y-block can be 80 mol% or less, 90 mol% or less, or 100 mol% or less. Any combination of these lower and upper limits is permissible. Considering the water resistance of the adhesive composition, the content of structural unit (M-3) in the Y-block is preferably 100 mol%. When the content of structural unit (M-3) is 50 mol% or more, the Y-block of the (meth)acrylic resin (A) exhibits good hydrophobicity, thus resulting in better water resistance of the obtained adhesive sheet. Therefore, when the adhesive sheet is used as a cutting tape or a cutting / chip bonding integrated film, it exhibits excellent water resistance and improved cutting performance even in processes involving water such as cutting water. When the content of the structural unit (M-3) is within the above-mentioned range, the Tg of the Y-block of the (meth)acrylic resin (A) can be adjusted to an appropriate range, thereby improving the adhesive strength.

[0095] Specifically, compounds (m-3) that provide the structural unit (M-3) can include alkyl methacrylates, styrene derivatives, etc. Examples of alkyl methacrylates include methyl methacrylate (18.8, 18.0), n-butyl methacrylate (19.0, 17.1), and other alkyl methacrylates having a straight or branched chain with alkyl groups having 1 to 5 carbon atoms; stearyl methacrylate (16.3, 16.3), isostearyl methacrylate (16.1, 16.1), and other alkyl methacrylates having a straight or branched chain with alkyl groups having 6 to 30 carbon atoms; and alkyl methacrylates... Cyclopentyl acrylate (18.0, 17.6), cyclohexyl methacrylate (18.0, 17.7), ethylcyclohexyl methacrylate (18.2, 17.6), norbornyl methacrylate (18.3, 18.0), dicyclopentyl methacrylate (17.6, 17.5), isobornyl methacrylate (17.1, 17.0), adamantyl methacrylate (17.7, 17.5), and other methacrylates containing an alicyclic skeleton. It should be noted that the SP values ​​(J / cm²) after the compound names are listed in the order of acrylate and methacrylate. 3 ) 1 / 2 Specific examples of styrene include styrene (18.3); alkyl derivatives of styrene such as α-methylstyrene (17.8), o-methylstyrene (18.3), m-methylstyrene (18.2), and p-methylstyrene (18.6). It should be noted that the numerical values ​​following the compound names are SP values ​​(J / cm²). 3 ) 1 / 2 From the perspective of reaction control and SP value, it is preferable to select at least one of the following: alkyl (meth)acrylates with a straight or branched chain of 6 to 30 carbon atoms, (meth)acrylates containing an alicyclic skeleton, and styrene; more preferably, it is selected from at least one of n-butyl acrylate, cyclohexyl acrylate, isostearyl acrylate, and styrene; even more preferably, it is selected from at least one of isostearyl acrylate and styrene; and particularly preferably, styrene. Compound (m-3) can be used alone or in combination of two or more.

[0096] Structural Unit (M-5)

[0097] When the total number of structural units in the Y-block of (meth)acrylic resin (A) is set to 100 mol%, the content of structural unit (M-5) in the Y-block can be 5 mol% or more, 10 mol% or more, or 15 mol% or more. When the total number of structural units in the Y-block of (meth)acrylic resin (A) is set to 100 mol%, the content of structural unit (M-5) in the Y-block is preferably 50 mol% or less, more preferably 40 mol% or less, and even more preferably 20 mol% or less. Any combination of these lower and upper limits is permissible. When the content of structural unit (M-5) in the Y-block is 5 mol% or more, the Tg of the Y-block of (meth)acrylic resin (A) can be adjusted to an appropriate range, thereby improving adhesive strength. When the content of structural unit (M-5) in the Y-block is 50 mol% or less, the Y-block of (meth)acrylic resin (A) exhibits good hydrophobicity, thus resulting in better water resistance of the obtained adhesive sheet. Therefore, when the adhesive sheet is used as a cutting tape or a cutting / chip bonding integrated film, it exhibits excellent water resistance and improved cutting performance even in processes involving water such as cutting water. From a water resistance perspective, the Y-block preferably does not contain structural unit (M-5). The structural unit (M-5) can be only one type or can be two or more types.

[0098] Examples of compounds that provide the structural unit (M-5) include compounds other than (m-1) and (m-2) that can copolymerize with compound (m-3) and have an SP value exceeding 20 (J / cm). 3 ) 1 / 2 Monomers. Specific examples include carboxyl-containing monomers; unsaturated dicarboxylic acid diesters; and other vinyl compounds.

[0099] Examples of carboxyl-containing monomers include methacrylic acid, crotonic acid, unsaturated monocarboxylic acids such as α-haloalkyl, alkoxy, halogen, nitro, or cyano-substituted derivatives of acrylic acid, and unsaturated dicarboxylic acids such as itaconic acid. Among these, methacrylic acid is preferred from the perspective of ease of manufacturing the adhesive layer.

[0100] Specific examples of unsaturated dicarboxylic acid diesters include diethyl citrate, diethyl maleate, diethyl fumarate, and diethyl itaconic acid.

[0101] Other examples of vinyl compounds include (meth)acrylamide, etc.

[0102] From a reaction control perspective, an SP value exceeding 20 (J / cm²) is preferred. 3 ) 1 / 2 Carboxyl-containing monomers.

[0103] For (meth)acrylic resin (A), without impairing the effect, the Y block may contain at least one selected from structural unit (M-1) and structural unit (M-2). Specific examples and preferred examples of the structural units (M-1) and (M-2) contained in the Y block are the same as those contained in the X block.

[0104] When the Y-block contains structural unit (M-1), and the total number of structural units in the Y-block of the (meth)acrylic resin (A) is set to 100 mol%, the content of structural unit (M-1) in the Y-block can be 1 mol% or more, 2 mol% or more, or 5 mol% or more. Regarding the content of structural unit (M-1) in the Y-block when it contains structural unit (M-1), when the total number of structural units in the Y-block of the (meth)acrylic resin (A) is set to 100 mol%, from the perspective of improving the water resistance of the adhesive sheet, it is preferably 15 mol% or less, more preferably 10 mol% or less, and even more preferably 5 mol% or less. Any combination of these lower and upper limits is permissible.

[0105] When the Y-block of the (meth)acrylic resin (A) contains a structural unit (M-1), the resin can be sufficiently thermocured through a heat-based crosslinking reaction. The resulting adhesive sheet exhibits good adhesion and excellent cutability when used as a cutting tape or a dicing / chip bonding integrated film. Furthermore, the adhesive layer achieves sufficient strength, preventing contamination of the adhered material during peeling. On the other hand, from the perspective of improving water resistance, it is preferable that the (meth)acrylic resin (A) does not contain a structural unit (M-1) in the Y-block.

[0106] When the Y-block of the (meth)acrylic resin (A) contains structural unit (M-2), if the total number of structural units in the Y-block of the (meth)acrylic resin (A) is set to 100 mol%, the content of structural unit (M-2) in the Y-block can be 1 mol% or more, 2 mol% or more, or 5 mol% or more. When the total number of structural units in the Y-block of the (meth)acrylic resin (A) is set to 100 mol%, the content of structural unit (M-2) in the Y-block when it contains structural unit (M-2) is preferably 15 mol% or less, more preferably 10 mol% or less, and even more preferably 5 mol% or less. Any combination of these lower and upper limits is permissible. When the Y-block of the (meth)acrylic resin (A) contains structural unit (M-2), after the adhesive sheet having the adhesive layer thereon is adhered to the substrate, the adhesive strength is reduced by UV irradiation, allowing for easy peeling from the substrate. When used as a cutting tape or a cutting / chip bonding integrated film, it exhibits excellent pick-up properties after UV irradiation. On the other hand, considering improved water resistance, it is preferable that the (meth)acrylic resin (A) does not have a structural unit (M-2) in the Y block.

[0107] <Photopolymerization Initiator (B)>

[0108] Examples of photopolymerization initiators (B) include benzophenone, benzoin, benzoin, ω-bromoacetophenone, chloroacetone, acetophenone, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, p-dimethylaminoacetophenone, p-dimethylaminoacetophenone, 2-chlorobenzophenone, 4,4'-dichlorobenzophenone, 4,4'-bis(diethylamino)benzophenone, michalcone, benzoin methyl ether, and benzoin... Carbonyl photopolymerization initiators such as isobutyl ether, benzoin n-butyl ether, benzyl methyl ketal, 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methyl-1-phenyl-propane-1-one, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropane-1-one, methyl benzoylformate, 4'-dimethylaminoacetophenone, and 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinylpropane-1-one.

[0109] Examples of photopolymerization initiators (B) include sulfide photopolymerization initiators such as diphenyl disulfide, dibenzyl disulfide, tetraethylthiuram disulfide, and tetramethylammonium monosulfide; acylphosphine oxides such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide and 2,4,6-trimethylbenzoylphenylethoxyphosphine oxide; quinone photopolymerization initiators such as benzoquinone and anthraquinone; sulfonyl chloride photopolymerization initiators; and thioxanthone photopolymerization initiators such as thioxanthone, 2-chlorothioxanthone, and 2-methylthioxanthone.

[0110] Among these photopolymerization initiators (B), carbonyl photopolymerization initiators and acylphosphine oxides are preferred in terms of solubility in the adhesive composition, and at least one selected from 1-hydroxycyclohexylphenyl ketone and 2,4,6-trimethylbenzoyldiphenylphosphine oxide is more preferred.

[0111] Photopolymerization initiator (B) can be used alone or in combination of two or more.

[0112] The photopolymerization initiator (B) is preferably 0.1 to 5.0 parts by weight, more preferably 0.3 to 2.0 parts by weight, relative to 100 parts by weight of the (meth)acrylic resin (A). When the content of the photopolymerization initiator (B) relative to 100 parts by weight of the (meth)acrylic resin (A) is 0.1 parts by weight or more, the crosslinking density of the photocrosslinking adhesive (i.e., the thermosetting product of the adhesive composition) can be increased at a sufficiently fast curing rate under UV irradiation. Therefore, when the photocrosslinking adhesive is used in the adhesive layer, the adhesive strength of the adhesive layer after UV irradiation can be sufficiently reduced. When the content of the photopolymerization initiator (B) relative to 100 parts by weight of the (meth)acrylic resin (A) is 5.0 parts by weight or less, the adhesive strength and water resistance of the adhesive layer before UV irradiation can be sufficiently maintained. Even if the content of photopolymerization initiator (B) exceeds 5.0 parts by mass relative to 100 parts by mass of (meth)acrylic resin (A), no effect commensurate with the content of photopolymerization initiator (B) is observed. Therefore, by setting the content to 5.0 parts by mass or less, adhesive compositions can be manufactured economically.

[0113] <Crosslinking agent (C)>

[0114] The crosslinking agent (C) is a compound without olefinic unsaturated bonds, possessing two or more functional groups that react with the hydroxyl groups contained in the (meth)acrylic resin (A). By heating the adhesive composition to allow the functional groups of the crosslinking agent (C) to react with the hydroxyl groups of the (meth)acrylic resin (A), a photocrosslinking adhesive can be obtained. When this photocrosslinking adhesive is used as an adhesive layer, an adhesive sheet with a good balance between adhesive strength before and after UV irradiation can be obtained.

[0115] The functional groups that are reactive to hydroxyl groups in the crosslinking agent (C) can include isocyanate groups, epoxy groups, carboxyl groups, acid anhydride groups, aziridinyl groups, etc. From the perspective of reactivity, isocyanate groups and epoxy groups are preferred, and isocyanate groups are particularly preferred.

[0116] Examples of crosslinking agents (C) include 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, hydrogenated toluene diisocyanate, 1,3-phenylenedimethylene diisocyanate, 1,4-phenylenedimethylene diisocyanate, diphenylmethane-4,4'-diisocyanate, isophorone diisocyanate, 1,3-bis(isocyanate methyl)cyclohexane, isocyanurate form of hexamethylene diisocyanate, tetramethylphenylenedimethylene diisocyanate, 1,5-naphthalene diisocyanate, and toluene diisocyanate of trimethylolpropane. Polyisocyanates including ester adducts, trimethylolpropane phenylenediamine diisocyanate adduct, triphenylmethane triisocyanate, and methylene bis(4-phenylmethane) triisocyanate; 1,3-bis(N,N'-diglycidylaminomethyl)cyclohexane; bisphenol A-epimerol type epoxy resins; N,N'-[1,3-phenylenebis(methylene)]bis[bis(ethylene oxide-2-ylmethyl)amine]; ethylene glycol diglycidyl ether; polyethylene glycol diglycidyl ether; glycerol diglycidyl ether; and glycerol triglycidyl ether. Polyepoxide compounds such as 1,6-hexanediol diglycidyl ether, trimethylolpropane triglycidyl ether, sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, and diglycerol polyglycidyl ether; melamine compounds such as hexamethoxymethyl melamine, hexaethoxymethyl melamine, hexapropoxymethyl melamine, hexabutoxymethyl melamine, hexapentoxymethyl melamine, and hexahexoxymethyl melamine; ethylene glycol-bis-[3-(2-aziridinyl)propionate], trimethylolpropane- Tris[3-(2-aziridinyl)propionate], trimethylolpropane-tris[3-(1-aziridinyl)propionate], trimethylolpropane-tris[3-(2-methyl-1-aziridinyl)propionate], tetramethylolmethane-tris[3-(2-aziridinyl)propionate], pentaerythritol-tris[3-(1-aziridinyl)propionate], N,N'-diphenylmethane-4,4'-bis(1-aziridinylcarboxamide), N,N'-hexamethylene-1,6-bis(1-aziridinylcarboxamide), and other aziridinyl compounds.

[0117] Among these crosslinking agents (C), considering their good reactivity with (meth)acrylic resins (A), at least one selected from polyisocyanates and polyepoxides is preferred, and polyisocyanates are more preferred.

[0118] Crosslinking agent (C) can be used alone or in combination of two or more.

[0119] The crosslinking agent (C) is preferably 0.1 to 30 parts by weight relative to 100 parts by weight of (meth)acrylic resin (A), more preferably 0.1 to 20 parts by weight, further preferably 0.1 to 10 parts by weight, and even more preferably 0.1 to 5 parts by weight. If the content of the crosslinking agent (C) relative to 100 parts by weight of (meth)acrylic resin (A) is 0.1 parts by weight or more, a three-dimensional crosslinked structure is sufficiently formed in the photocrosslinking adhesive upon UV irradiation. Therefore, when the photocrosslinking adhesive is used as an adhesive, the adhesive strength of the adhesive after UV irradiation can be sufficiently reduced. If the content of the crosslinking agent (C) relative to 100 parts by weight of (meth)acrylic resin (A) is 30 parts by weight or less, the properties of the photocrosslinking adhesive and the cured product after UV irradiation are well balanced, exhibiting good adhesion and water resistance when used as a cutting tape or a cutting / chip bonding integrated film. When the photocrosslinking adhesive is used as an adhesive, the adhesive strength of the adhesive is good before UV irradiation.

[0120] <Other Ingredients>

[0121] The adhesive composition may contain other components besides (meth)acrylic resin (A), photopolymerization initiator (B), and crosslinking agent (C), as needed. Other components may include, for example, tackifiers, solvents, and various additives.

[0122] (Thickening agent)

[0123] As a tackifier, conventionally known tackifiers can be used without particular restriction. Examples of tackifiers include terpene tackifiers, phenolic tackifiers, rosin tackifiers, aliphatic petroleum resins, aromatic petroleum resins, copolymer petroleum resins, alicyclic petroleum resins, xylene resins, epoxy tackifiers, polyamide tackifiers, ketone tackifiers, and elastomer tackifiers. These tackifiers can be used alone or in combination of two or more.

[0124] When using a tackifier, the content of the tackifier in the adhesive composition relative to 100 parts by weight of (meth)acrylic resin (A) is preferably 30 parts by weight or less, more preferably 5 to 20 parts by weight.

[0125] (solvent)

[0126] The solvent can be used to dilute the adhesive composition for the purpose of adjusting its viscosity. For example, in the case of coating the adhesive composition, the solvent can be used to adjust the viscosity of the adhesive composition to an appropriate viscosity. As a solvent, the solvent used in the synthesis of (meth)acrylic resin (A) can be used directly, or additional solvent can be added to that solvent.

[0127] As solvents, organic solvents such as methyl ethyl ketone, methyl isobutyl ketone, acetone, ethyl acetate, propyl acetate, butyl acetate, tetrahydrofuran, dioxane, cyclohexanone, hexane, toluene, xylene, n-propanol, and isopropanol can be used. These solvents can be used alone or in combination of two or more.

[0128] (additive)

[0129] Examples of additives include plasticizers, surface lubricants, leveling agents, softeners, antioxidants, anti-aging agents, light stabilizers, ultraviolet absorbers, polymerization inhibitors, light stabilizers such as benzotriazoles, phosphate esters and other flame retardants, surfactants, and antistatic agents.

[0130] [Manufacturing method of (meth)acrylic resin (A)]

[0131] For (meth)acrylic resin (A), it can be manufactured, for example, by a method comprising a step (i-1) of reversible addition-fragmentation chain transfer (RAFT) polymerization of the raw material monomer group (mX) constituting block X, a step (i-2) of reversible addition-fragmentation chain transfer (RAFT) polymerization of the raw material monomer group (mY) constituting block Y, and a step (ii) of introducing olefinic unsaturated groups by adding an olefinic unsaturated compound having functional groups such as isocyanate groups to a portion of the hydroxyl groups of the copolymer obtained by steps (i-1) and (i-2) as needed. The order of steps (i-1) and (i-2) for synthesizing each block is not particularly limited, but step (i-2) is preferably performed before step (i-1). Hereinafter, exemplary embodiments of steps (i-1), (i-2), and (ii) will be described.

[0132] <Process (i-1)>

[0133] Step (i-1) is a step of RAFT polymerization of a group of raw monomers (mX) in the presence of a reversible addition-fragmentation chain transfer agent (RAFT agent), said raw monomer group (mX) comprising an olefinically unsaturated compound having hydroxyl groups (m-1), optionally a (meth)acrylate having olefinically unsaturated groups other than (meth)acryloyloxy groups (m-2), and optionally other monomers other than compounds (m-1) and (m-2). In this specification, RAFT polymerization refers to free radical polymerization carried out in the presence of a RAFT agent. RAFT polymerization is a type of living radical polymerization. Living radical polymerization is generally known as a polymerization method that can obtain polymers with small molecular weight distributions; specific examples include atom transfer radical polymerization, organotellurium-mediated free radical polymerization, and RAFT polymerization. RAFT polymerization is particularly suitable for adhesive applications.

[0134] The weight-average molecular weight of each block obtained through processes (i-1) and (i-2) can be controlled, for example, by adjusting the amount of free radical polymerization initiator and RAFT agent used. By controlling the weight-average molecular weight of each block, the ratio (molar ratio) of the structural units of the X and Y blocks can be controlled within the desired range.

[0135] The reaction temperature can be appropriately set according to the type of free radical polymerization initiator used. The preferred reaction temperature is 40–125°C, more preferably 60–120°C. The reaction time can be appropriately set according to the type of free radical polymerization initiator used. The preferred reaction time is 5–24 hours, more preferably 10–15 hours.

[0136] As polymerization methods, solution polymerization, emulsion polymerization, bulk polymerization, suspension polymerization, and alternating copolymerization can be used. Among these polymerization methods, considering the addition reaction in step (ii), solution polymerization is preferred from the perspective of the ease of reaction.

[0137] Considering the polymerization rate of the raw material monomer group (mX), the total concentration of components other than the solvent in solution polymerization is preferably 30 to 90% by mass, more preferably 50 to 80% by mass. Since steps (i-1) and (i-2) are RAFT polymerizations, polymerization is carried out through an equilibrium reaction. Therefore, the polymerization proceeds very gently, and polymerization can be carried out at high concentrations.

[0138] (Reversible addition-fragmentation chain transfer agent (RAFT agent))

[0139] As a RAFT agent, any known RAFT agent can be used without particular restriction, as long as it is a type of RAFT agent in which the polymer elongates in one direction starting from a thiocarbonyl thio group. Examples of RAFT agents include trithiocarbonates, dithioesters, dithiocarbonates, and dithiocarbamates. When polymerization occurs in the presence of these RAFT agents, the free radical species undergo a chain reaction between the sulfur atom in the RAFT agent and the carbon atom adjacent to that sulfur atom. Among these, trithiocarbonates are preferred from the viewpoint that the reaction rate and reaction ratio of polymerization can be increased depending on the magnitude of the transfer constant, and the molecular weight distribution can be narrowed. It should be noted that for symmetrical trithiocarbonates, the polymer elongates in two directions starting from the trithiocarbonate site. Therefore, when polymerization is carried out in the order of steps (i-1) and (i-2), an XYX type triblock copolymer is formed, and when polymerization is carried out in the order of steps (i-2) and (i-1), a YXY type triblock copolymer is formed, which is unusable.

[0140] Specific examples of RAFT agents include sulfur compounds (trithiocarbonates, dithioesters, dithiocarbonates and dithiocarbamates) represented by the following formulas (1), (2), (3) or (4).

[0141] Trithiocarbonates

[0142]

[0143] In equation (1), R 1a and R 1b Each can independently represent a hydrogen atom, hydrocarbon group, carboxyl group, or cyano group, R 1c R represents a cyano group, a saturated or unsaturated aliphatic hydrocarbon group that can be substituted with a cyano or carboxyl group, or a substituted phenyl group. 2 This indicates a saturated or unsaturated aliphatic hydrocarbon group, in which some of its hydrogen atoms can be replaced by a carboxyl group, or a benzyl group, in which some of the hydrogen atoms can be replaced by a carbamoyl group, an alkoxycarbonyl group with 2 to 5 carbon atoms that can be replaced by a hydroxyl group, or an alkenoxycarbonyl group with 3 to 5 carbon atoms. However, (R...) 1a (R) 1b (R) 1c C and R 2 different.

[0144] Dithioesters

[0145]

[0146] In equation (2), R 3a and R 3b Each can independently represent a hydrogen atom, a hydrocarbon group, or a cyano group, R3c R represents a carboxyl group, an acetoxymethyl group, or a hydrocarbon group that can be substituted with a cyano or carboxyl group. 4 It indicates a hydrocarbon group.

[0147] Dithiocarbonates

[0148]

[0149] In equation (3), R 5a and R 5b Each independently represents a hydrogen atom, a hydrocarbon group, a carboxyl group that can be substituted by a saturated aliphatic hydrocarbon group having 1 to 3 carbon atoms, or a cyano group, R. 5c R represents a hydrocarbon group that can be substituted with an alkoxy group. 6 It represents a hydrocarbon group.

[0150] Dithiocarbamates

[0151]

[0152] In equation (4), R 7a and R 7b Each can independently represent a hydrogen atom or a hydrocarbon group, R 7c R represents cyano group. 8 and R 9 Each can independently represent a hydrocarbon group, or R 8 and R 9 They can bond to form saturated aliphatic hydrocarbon groups with 1 to 3 carbon atoms or pyrazole rings that can be replaced by chlorine atoms.

[0153] In equation (1), R is used as 1a and R 1b The hydrocarbon group represented can be, for example, a straight-chain, branched-chain, or cyclic saturated or unsaturated hydrocarbon group having 1 to 20 carbon atoms, wherein a straight-chain, branched-chain, or cyclic saturated or unsaturated hydrocarbon group having 1 to 12 carbon atoms is preferred. Examples of such hydrocarbon groups include, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, cyclohexyl, undecyl, dodecyl, octadecyl, etc., which are straight-chain, branched-chain, or cyclic saturated aliphatic hydrocarbon groups having 1 to 20 carbon atoms; aryl groups having 6 to 12 carbon atoms such as phenyl; and arylalkyl groups having 7 to 10 carbon atoms such as benzyl, phenethyl, etc. In formula (1), R... 1cThe saturated or unsaturated aliphatic hydrocarbon group can be exemplified by, for example, straight-chain, branched-chain, or cyclic saturated or unsaturated aliphatic hydrocarbon groups having 1 to 20 carbon atoms, with a preference for straight-chain, branched-chain, or cyclic saturated or unsaturated aliphatic hydrocarbon groups having 1 to 12 carbon atoms. Examples of such aliphatic hydrocarbon groups include, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, cyclohexyl, undecyl, dodecyl, octadecyl, and other straight-chain, branched-chain, or cyclic saturated aliphatic hydrocarbon groups having 1 to 20 carbon atoms. In formula (1), R... 1c One to three hydrogen atoms in the saturated or unsaturated aliphatic hydrocarbon group can be replaced by a carboxyl or cyano group, and the carboxyl group can be further replaced by a saturated aliphatic hydrocarbon group having 1 to 3 carbon atoms. In formula (1), R is... 1c Examples of substituents for the substituted phenyl group include substituted carbamoyl groups, alkoxycarbonyl groups with 2 to 5 carbon atoms that can be substituted with a hydroxyl group, and olefinic carbonyl groups with 3 to 5 carbon atoms. Examples of substituents for the aforementioned substituted carbamoyl groups include saturated aliphatic hydrocarbon groups with 1 to 3 carbon atoms that can be substituted with a hydroxyl or acetoxy group. In formula (1), R... 2 The saturated or unsaturated aliphatic hydrocarbon group represented can be exemplified by straight-chain, branched-chain, or cyclic saturated or unsaturated aliphatic hydrocarbon groups having 1 to 20 carbon atoms, with aliphatic hydrocarbon groups having 1 to 12 carbon atoms being preferred. Examples of such aliphatic hydrocarbon groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, cyclohexyl, dodecyl, octadecyl, and other straight-chain, branched-chain, or cyclic saturated aliphatic hydrocarbon groups having 1 to 20 carbon atoms. In formula (1), R... 2 One to three hydrogen atoms in the saturated or unsaturated aliphatic hydrocarbon group can be replaced by a carboxyl group. In formula (1), R... 2 The substituent of the benzyl group, which can be substituted, is the substituent of the carbamoyl group. Examples include saturated aliphatic hydrocarbon groups with 1 to 3 carbon atoms that can be substituted by a hydroxyl or acetoxy group. Among them, R is preferred. 1a and R 1b Each is independently a hydrogen atom, a hydrocarbon group with 1 to 4 carbon atoms, a carboxyl group, or a cyano group, R 1c It is an undecyl group, a hydrocarbon group with 1 to 4 carbon atoms that can be substituted by a carboxyl group, or a substituted phenyl group, R 2 Compounds represented by formula (1) having a straight-chain, branched-chain, or cyclic, saturated or unsaturated aliphatic hydrocarbon group or a substituted benzyl group having 1 to 20 carbon atoms, more preferably R 1a and R 1b R is a combination of a hydrogen atom, a methyl or ethyl group and a cyano or carboxyl group, or a hydrogen atom. 1cR is methyl, ethyl, undecyl, or a substituted phenyl group. 2 The compound represented by formula (1) is a straight-chain saturated aliphatic hydrocarbon group or benzyl group with 1 to 20 carbon atoms, wherein some of the hydrogen atoms of the benzyl group may be replaced by a carbamoyl group, an alkoxy carbonyl group with 2 to 5 carbon atoms that may be replaced by a hydroxyl group, or an olefinic carbonyl group with 3 to 5 carbon atoms.

[0154] In equation (2), R is used as 3a R 3b R 3c and R 4 The hydrocarbon group represented can be, for example, a straight-chain, branched-chain, or cyclic saturated or unsaturated hydrocarbon group having 1 to 20 carbon atoms, wherein a straight-chain, branched-chain, or cyclic saturated or unsaturated hydrocarbon group having 1 to 12 carbon atoms is preferred. Examples of such hydrocarbon groups include, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, cyclohexyl, dodecyl, octadecyl, etc., which are straight-chain, branched-chain, or cyclic saturated aliphatic hydrocarbon groups having 1 to 20 carbon atoms; aryl groups having 6 to 12 carbon atoms such as phenyl; and arylalkyl groups having 7 to 10 carbon atoms such as benzyl, phenethyl, etc. In formula (2), R... 3c The hydrocarbon group that can be substituted with a cyano or carboxyl group can be exemplified by groups in which 1 to 3 hydrogen atoms of the aforementioned hydrocarbon group are substituted with a cyano or carboxyl group. Among these, R is preferred. 3a and R 3b Each is independently a straight-chain saturated hydrocarbon group with 1 to 4 carbon atoms, R 3c For aryl, R 4 Compounds of formula (2) that are aryl or benzyl, more preferably R 3a and R 3b Each independently is methyl or ethyl, R 3c For phenyl, R 4 Compounds represented by formula (2) that are phenyl or benzyl.

[0155] In equation (3), R is used as 5a R 5b R 5c and R 6 The hydrocarbon group represented can be, for example, a straight-chain, branched-chain, or cyclic saturated or unsaturated hydrocarbon group having 1 to 20 carbon atoms, wherein a straight-chain, branched-chain, or cyclic saturated or unsaturated hydrocarbon group having 1 to 12 carbon atoms is preferred. Examples of such hydrocarbon groups include, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, cyclohexyl, dodecyl, octadecyl, etc., which are straight-chain, branched-chain, or cyclic saturated aliphatic hydrocarbon groups having 1 to 20 carbon atoms; aryl groups having 6 to 12 carbon atoms such as phenyl; and arylalkyl groups having 7 to 10 carbon atoms such as benzyl, phenethyl, etc. In formula (3), R...5c Examples of hydrocarbon groups that can be substituted with alkoxy groups include, for example, groups in which 1 to 3 hydrogen atoms of the aforementioned hydrocarbon groups are substituted with alkoxy groups.

[0156] In equation (4), R is used as 7a R 7b R 8 and R 9 The hydrocarbon group represented can be, for example, a straight-chain, branched-chain, or cyclic saturated or unsaturated hydrocarbon group having 1 to 20 carbon atoms, wherein a straight-chain, branched-chain, or cyclic saturated or unsaturated hydrocarbon group having 1 to 12 carbon atoms is preferred. Examples of such hydrocarbon groups include, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, cyclohexyl, dodecyl, octadecyl, and other straight-chain, branched-chain, or cyclic saturated aliphatic hydrocarbon groups having 1 to 20 carbon atoms; aryl groups having 6 to 12 carbon atoms such as phenyl; and arylalkyl groups having 7 to 10 carbon atoms such as benzyl and phenethyl. 8 and R 9 It can form a pyrazole ring together with the nitrogen atom of formula (4). The pyrazole ring can be replaced by a saturated aliphatic hydrocarbon group with 1 to 3 carbon atoms or a chlorine atom.

[0157] Many RAFT agents are commercially available. Substances that are not commercially available can be readily synthesized using known or conventional methods.

[0158] Specific examples of RAFT agents include S-cyanomethyl-S-dodecyl trithiocarbonate, 2-[(dodecylthioalkylthiocarbonyl)thioalkyl]propionic acid, 2-{[(2-carboxyethyl)thioalkylthiocarbonyl]thioalkyl}propionic acid, 4-[(2-carboxyethylthioalkylthiocarbonyl)thioalkyl]-4-cyanopentanoic acid, 4-cyano-4-[(dodecylthioalkylthiocarbonyl)thioalkyl]pentanoic acid, methyl 4-cyano-4-[(dodecylthioalkylthiocarbonyl)thioalkyl]pentanoic acid, methyl 2-cyano-2-propyldodecyl trithiocarbonate, benzyl dodecyl trithiocarbonate, and other trithiocarbonates; cyanoethyl dithiopropionate, benzyl dithiopropionate, benzyl dithiobenzoate, acetoxyethyl dithiobenzoate, 2-phenyl-2-propyl dithiobenzoic acid, 2-cyano... Dithioesters such as 2-propyl dithiobenzoic acid, 4-cyano-4-(phenylthiocarbonylthio)valeric acid, and S-(thiobenzoyl)mercaptoacetic acid; dithiocarbonates such as ethyl 2-[(ethoxythiocarbonyl)thio]propionate, S-(2-propoxyethyl)dithiocarbonate O-ethyl ester, and S-(1-cyano-1-methylethyl)dithiocarbonate O-ethyl ester; dithiocarbonates such as 2-cyano-2-propyldiethyl dithiocarbamate, 2'-cyanobutane-2'-yl4-chloro-3,5-dimethylpyrazole-1-dithiocarbamate, 2'-cyanobutane-2'-yl3,5-dimethylpyrazole-1-dithiocarbamate, cyanomethyl 3,5-dimethylpyrazole-1-dithiocarbamate, and cyanomethyl N-methyl-N-phenyl dithiocarbamate, etc. Among them, considering the ease of polymerization of (meth)acrylic resin (A), trithiocarbonate and dithioester are preferred, and 2-[(dodecylthioalkylthiocarbonyl)thioalkyl]propionic acid, 4-cyano-4-[(dodecylthioalkylthiocarbonyl)thioalkyl]valeric acid, 2-{[(2-carboxyethyl)thioalkylthiocarbonyl]thioalkyl}propionic acid, benzyl dodecyl trithiocarbonate and 2-phenyl-2-propyl dithiobenzoic acid are preferred.

[0159] RAFT agents can be used alone or in combination of two or more.

[0160] If step (i-2) is performed before step (i-1), a diblock copolymer can be obtained by continuing to use the RAFT agent formulated in step (i-2), which is composed of blocks synthesized from raw material monomer group (mX) and blocks synthesized from raw material monomer group (mY).

[0161] The amount of RAFT agent used is preferably 0.001 to 1.0 parts by mass relative to a total of 100 parts by mass of the raw material monomer group (mX), the raw material monomer group (mY), and optionally, olefinic unsaturated compounds with functional groups such as isocyanate groups. More preferably, it is 0.005 to 0.5 parts by mass, and even more preferably, it is 0.01 to 0.35 parts by mass. If it is 0.001 parts by mass or more, polymerization can be carried out with an effective reaction time. If it is 1.0 parts by mass or less, sufficiently high molecular weight blocks can be obtained.

[0162] (Free radical polymerization initiator)

[0163] RAFT polymerization is preferably carried out in the presence of a free radical polymerization initiator. Examples of conventional organic free radical polymerization initiators include, specifically, 2,2'-azobis(isobutyronitrile), 2,2'-azobis(4-methoxy-2,4-dimethylpentanitrile), 2,2'-azobis(2,4-dimethylpentanitrile), 2,2'-azobis(2-methylbutyronitrile), 1,1'-azobis(cyclohexane-1-carboxynitrile), and 2,2'-azobis(2,4,4-trimethylpentane). Azo polymerization initiators such as dimethyl-2,2'-azobis(2-methylpropionate) and 2,2'-azobis(N-butyl-2-methylpropionamide); and oil-soluble polymerization initiators such as benzoyl peroxide, tert-butyl hydroperoxide, di-tert-butyl peroxide, tert-butyl peroxide, dicumyl peroxide, 1,1-bis(tert-butylperoxide)-3,3,5-trimethylcyclohexane, and 1,1-bis(tert-butylperoxide)cyclododecane.

[0164] Among these free radical polymerization initiators, considering the 10-hour half-life temperature and solubility in organic solvents, azo polymerization initiators are preferred, and at least one selected from 2,2'-azobis(isobutyronitrile), 2,2'-azobis(4-methoxy-2,4-dimethylpentanonitrile), 2,2'-azobis(2,4-dimethylpentanonitrile), 2,2'-azobis(2-methylbutyronitrile), and 2,2'-azobis(N-butyl-2-methylpropionamide) is more preferred.

[0165] Free radical polymerization initiators can be used alone or in combination of two or more.

[0166] If step (i-2) is performed before step (i-1), the free radical polymerization initiator used in step (i-2) can continue to be used. To replenish the free radical polymerization initiator deactivated in step (i-2), additional free radical polymerization initiator can be added in step (i-1). Considering reactivity and molecular weight control, it is preferable to add additional free radical polymerization initiator in step (i-1).

[0167] The amount of free radical polymerization initiator added in step (i-1) is preferably 0.0001 to 1.0 parts by mass, more preferably 0.001 to 0.5 parts by mass, and even more preferably 0.005 to 0.1 parts by mass, relative to 100 parts by mass of the total amount of raw material monomer group (mX), raw material monomer group (mY), and optionally the olefinic unsaturated compound having functional groups such as isocyanate groups. If it is 0.0001 parts by mass or more, polymerization can be carried out with an effective reaction time. If it is 1.0 parts by mass or less, sufficiently high molecular weight blocks can be obtained.

[0168] From the perspective of prioritizing the active radical polymerization over the free radical polymerization, the molar ratio of the free radicals generated by the free radical polymerization initiator added in step (i-1) to the RAFT agent is preferably 1.0:1.0 to 1.0:1.5.

[0169] (solvent)

[0170] As solvents that can be used in step (i-1), conventional solvents can be used. Examples of solvents include esters such as ethyl acetate, propyl acetate, and butyl acetate; aromatic hydrocarbons such as toluene, xylene, and benzene; aliphatic hydrocarbons such as hexane and heptane; alicyclic hydrocarbons such as cyclohexane and methylcyclohexane; ketones such as methyl ethyl ketone and methyl isobutyl ketone; glycols such as ethylene glycol, propylene glycol, and dipropylene glycol; glycol ethers such as methyl cellosolve, propylene glycol monomethyl ether, and dipropylene glycol monomethyl ether; and glycol esters such as ethylene glycol diacetate and propylene glycol monomethyl ether acetate. Solvents can be used alone or in combination of two or more.

[0171] If step (i-2) is performed before step (i-1), the solvent used in step (i-2) can be used again, or it can be added in step (i-1) in one step.

[0172] <Process (i-2)>

[0173] Step (i-2) involves, in the presence of a reversible addition-fragmentation chain transfer agent (RAFT agent), adding an SP value of 20 (J / cm²) to the mixture. 3 ) 1 / 2 The process of RAFT polymerization of the following olefinic unsaturated compounds (m-3) and optional monomers other than (m-3) as raw material monomers (mY).

[0174] The reaction temperature, reaction time, polymerization method, concentration and other conditions can be set appropriately in the same way as in process (i-1).

[0175] For the RAFT agent, the same substance as in step (i-1) can be used, and the preferred RAFT agent is also the same. If step (i-1) is performed before step (i-2), by continuing to use the RAFT agent formulated in step (i-1), a diblock copolymer in which blocks synthesized from the raw material monomer group (mX) are attached to blocks synthesized from the raw material monomer group (mY).

[0176] For the free radical polymerization initiator, the same material as in step (i-1) can be used, and the preferred free radical polymerization initiator is also the same. If step (i-1) is performed before step (i-2), the free radical polymerization initiator formulated in step (i-1) can continue to be used. To replenish the free radical polymerization initiator deactivated in step (i-1), a further addition of free radical polymerization initiator can be made in step (i-2). From the perspective of reactivity and molecular weight control, it is preferable to further add the free radical polymerization initiator in step (i-2).

[0177] The amount of free radical polymerization initiator added in step (i-2) is preferably 0.0001 to 1.0 parts by mass, more preferably 0.001 to 0.5 parts by mass, and even more preferably 0.005 to 0.1 parts by mass, relative to 100 parts by mass of the total amount of the raw material monomer group (mX), the raw material monomer group (mY), and optionally the olefinic unsaturated compound having functional groups such as isocyanate groups. If it is 0.0001 parts by mass or more, polymerization can be carried out with an effective reaction time. If it is 1.0 parts by mass or less, sufficiently high molecular weight blocks can be obtained.

[0178] From the perspective of prioritizing the active radical polymerization over the free radical polymerization, the molar ratio of the free radicals generated by the free radical polymerization initiator added in step (i-2) to the RAFT agent is preferably 1.0:1.0 to 1.0:1.5.

[0179] For the solvent, the same solvent as in step (i-1) can be used. If step (i-1) is performed before step (i-2), the solvent used in step (i-1) can continue to be used, or additional solvent can be added in step (i-2).

[0180] <Process (ii)>

[0181] Step (ii) is a step in which an olefinic unsaturated compound is added to a portion of the side-chain hydroxyl groups of the copolymer obtained through steps (i-1) and (i-2) to introduce olefinic unsaturated groups. If an olefinic unsaturated compound is added to all the side-chain hydroxyl groups of the copolymer obtained through steps (i-1) and (i-2), the resulting copolymer will not contain hydroxyl groups, and its adhesive strength as an adhesive sheet will become insufficient. Furthermore, if an olefinic unsaturated compound is added to all the side-chain hydroxyl groups of the copolymer obtained through steps (i-1) and (i-2), the reaction site with the crosslinking agent (C) described later will disappear. Therefore, addition is performed only on a portion of the side-chain hydroxyl groups. Specifically, when the side-chain hydroxyl groups are set to 100 mol%, the addition reaction is preferably performed at 40 to 99 mol%. There are no particular limitations on the method of adding the olefinic unsaturated compound, and methods known in the technical field of this specification can be used. For (meth)acrylic resin (A), due to the presence of olefinically unsaturated groups on its side chains, the molecular chain length between crosslinking points is relatively short compared to (meth)acrylic copolymers with olefinically unsaturated groups introduced at the ends, allowing for effective increases in crosslinking density through UV irradiation. Therefore, when (meth)acrylic resin (A) is used in adhesive materials, the adhesive strength after UV irradiation can be significantly reduced. Consequently, adhesive sheets using (meth)acrylic resin (A) exhibit excellent peelability from the adhered object. Furthermore, adhesive compositions made using (meth)acrylic resin (A) demonstrate excellent adhesion to the adhesive layer. Therefore, adhesive compositions made using (meth)acrylic resin (A) are suitable for use as adhesive layers in cut tapes.

[0182] (catalyst)

[0183] In the addition reaction of step (ii), a known catalyst may be used as needed. For example, as a catalyst for the addition of an olefinic unsaturated compound (a) containing an isocyanate group to a side chain hydroxyl group, carbamate catalysts such as dibutyltin dilaurate, diisopropoxybis(ethyl acetoacetate)titanium, tetrazirconium tetra(2,4-pentanedione), and tris(2-ethylhexanoate)bismuth may be used.

[0184] When a catalyst is used in step (ii) to add side-chain hydroxyl groups to an olefinic unsaturated compound (a) containing isocyanate groups, the amount of catalyst used is preferably 0.01 to 10 parts by mass, more preferably 0.02 to 5 parts by mass, and even more preferably 0.03 to 1 part by mass, relative to a total of 100 parts by mass of the copolymer obtained by steps (i-1) and (i-2) and the olefinic unsaturated compound (a) containing isocyanate groups.

[0185] (polymerization inhibitor)

[0186] In the addition reaction of step (ii), a known polymerization inhibitor may be used as needed. There are no particular limitations on the known polymerization inhibitors that may be used, such as 4-methoxyphenol, hydroquinone, p-hydroxyanisole, 2,6-di-tert-butylphenol, 2,2'-methylenebis(4-methyl-6-tert-butylphenol), and phenothiazine. The polymerization inhibitor may be used alone or in combination of two or more.

[0187] When a polymerization inhibitor is used in step (ii), the amount of the inhibitor used is preferably 0.005 to 5 parts by mass, more preferably 0.03 to 3 parts by mass, and even more preferably 0.05 to 1.5 parts by mass, relative to a total of 100 parts by mass of the copolymer and olefin unsaturated compound obtained through steps (i-1) and (i-2). If the amount of the polymerization inhibitor used is 0.005 parts by mass or more, gelation during the addition reaction can be prevented. On the other hand, if the amount of the polymerization inhibitor used is 5 parts by mass or less, sufficient exposure sensitivity of the (meth)acrylic resin (A) can be obtained when subjected to UV irradiation.

[0188] (Reaction conditions)

[0189] The addition reaction temperature is preferably 25°C to 130°C, and particularly preferably 40°C to 90°C. A sufficient reaction rate can be obtained if the addition reaction temperature is above 25°C. If the addition reaction temperature is below 130°C, cross-linking of the double bond portion due to thermal free radical polymerization and the formation of gels can be prevented.

[0190] During addition reactions, a gas with polymerization inhibitory effects can be introduced into the reaction system. By introducing a gas with polymerization inhibitory effects into the reaction system, gelation during the addition reaction can be prevented.

[0191] Gases that have a polymerization-inhibiting effect include gases containing oxygen at a level that does not enter the explosive range of substances within the system, such as air.

[0192] If both a gas and an inhibitor with polymerization inhibitory effect are used simultaneously, the amount of inhibitor used can be reduced or the polymerization inhibitory effect can be improved, which is therefore preferred.

[0193] [Method for manufacturing adhesive composition]

[0194] <Process (iii)>

[0195] The adhesive composition can be manufactured, for example, by a method comprising step (iii) of mixing (meth)acrylic resin (A), photopolymerization initiator (B), crosslinking agent (C), and other components to be added as needed.

[0196] There are no particular limitations on the method of mixing the components contained in the adhesive composition. For example, a homogenizer or a stirring device equipped with paddle blades can be used for mixing.

[0197] [Manufacturing method of photocrosslinking adhesive]

[0198] Process (iv)

[0199] For photocrosslinkable adhesives, they can be manufactured, for example, by a method comprising a step (iv) of applying an adhesive composition to a substrate or release sheet and thermally curing it.

[0200] For the adhesive composition, the adhesive composition obtained in step (iii) can be used directly, or an adhesive composition whose viscosity has been adjusted by adding further solvent can be used.

[0201] Thermosetting is performed by heating, drying, and curing as needed during the formation of the photocrosslinking adhesive. For example, as an embodiment of step (iv), an adhesive composition is coated onto a substrate, and the solvent is removed by heating and drying in the presence of a solvent, forming an adhesive composition layer. Then, a release liner is attached to the adhesive composition layer as needed. Furthermore, the resulting sheet is cured in an oven for a certain period of time as needed to form a crosslinked structure, thereby obtaining a layer of photocrosslinking adhesive.

[0202] According to another embodiment, step (iv) includes a step (iv-1) of coating an adhesive composition onto a release sheet to obtain an adhesive composition layer, a step (iv-2) of thermosetting the adhesive composition layer to obtain a photocrosslinkable adhesive layer, and a step (iv-3) of laminating a substrate onto the adhesive composition layer or the photocrosslinkable adhesive layer. Step (iv-3) can be performed between steps (iv-1) and (iv-2) or after step (iv-2). For example, an adhesive composition is coated onto a release sheet, and the solvent is removed by heating and drying in the presence of a solvent to form an adhesive composition layer (step (iv-1)). Then, the release sheet having the adhesive composition layer is placed on the substrate with the adhesive composition layer side facing the substrate, and the adhesive composition layer is transferred onto the substrate (step (iv-3)). Furthermore, the resulting sheet is cured in an oven for a certain time as needed to form a crosslinked structure, thereby obtaining a photocrosslinkable adhesive layer (step (iv-2)).

[0203] As a method for applying an adhesive composition to a substrate or release liner, known methods can be used. Specifically, methods for applying the composition using conventional coating machines, such as gravure roller coating machines, reverse roller coating machines, licking roller coating machines, dip roller coating machines, bar coating machines, doctor blade coating machines, spray coating machines, comma coating machines, direct coating machines, etc., can be listed.

[0204] There are no particular limitations on the conditions for heating and drying the coated adhesive composition. Generally, heating and drying at 25–180°C, preferably 60–150°C, for 1–20 minutes, and more preferably 1–10 minutes, is performed. Heating and drying within the above range removes the solvent contained in the adhesive composition. There are no particular limitations on the conditions for curing the heated and dried sheet in an oven for a certain period. Generally, curing at 25–100°C, preferably 30–80°C, for 1–30 days, and more preferably 1–14 days, is performed. Curing under the above conditions allows the (meth)acrylic resin (A) to be crosslinked using the crosslinking agent (C), adjusting the gel fraction of the photocrosslinking adhesive to the desired range.

[0205] [Adhesive sheet]

[0206] The adhesive sheet has a substrate layer and an adhesive layer formed from a thermosetting or photothermal curing agent of the adhesive composition. For the adhesive sheet, a release liner may be provided on the exposed side of the adhesive layer (i.e., the side opposite to the substrate layer) as needed before bonding to the substrate. The adhesive sheet can be obtained, for example, through process (iv). When bonded to the substrate, the adhesive layer is used as a photocrosslinked adhesive layer; when peeled off from the substrate, the photocrosslinked adhesive layer is crosslinked by UV irradiation, thereby reducing the adhesive strength.

[0207] There are no particular restrictions on the substrate, and it can be selected appropriately according to the application. Resin films are generally preferred. Examples of resin materials include polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), polyolefins (PO), polyesters, polyurethanes, polycarbonates, polyetheretherketones (PEs), polyimides, polyetherimides, polyamides, fully aromatic polyamides (aromatic polyamides), polyphenylene sulfide (PPS), fluoropolymers, cellulose resins, and silicone resins. Examples of polyolefins include low-density polyethylene (LDPE), linear polyethylene (LLDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), ultra-low-density polyethylene (ULDPE), etc.; polypropylene (PP) including random copolymers, block copolymers, homopolymers, etc.; polybutene; polymethylpentene; ethylene-vinyl acetate copolymers; ionomer resins; ethylene-(meth)acrylate copolymers; ethylene-(meth)acrylate copolymers; ethylene-butene copolymers; and ethylene-hexene copolymers. Examples of polyesters include polyethylene terephthalate (PET), polyethylene naphthalate (PET), and polybutylene terephthalate (PBT). Among these resin materials, one or more selected from PE, PP, and PET are particularly preferred for obtaining adhesive sheets with moderate flexibility. The resin material used as the base material may be a single type or a mixture of two or more. In the case of cutting tape, polyolefins are preferred.

[0208] The substrate can be composed of one material or two or more materials. It can have a single-layer or multi-layer structure. Since the photocrosslinking adhesive on the substrate is UV-curable, the substrate preferably has UV transmittance. When the substrate is a resin film, it can be a non-stretchable film, a uniaxially stretched film, or a biaxially stretched film.

[0209] The substrate can be a substrate that has undergone treatment to improve adhesion. Examples of such treatments include physical treatments such as corona discharge treatment, plasma treatment, sanding treatment, ozone exposure treatment, flame exposure treatment, high voltage electric shock exposure treatment, ionization radiation treatment, chemical treatments such as chromic acid treatment, and primer treatment.

[0210] PO film is preferably used as the substrate. However, PO film has low heat resistance and is not suitable for the aforementioned heating and drying temperatures. Therefore, it is preferable to coat an adhesive composition onto a release sheet, heat-dry it to remove the solvent, and then transfer and adhere the adhesive composition layer onto the PO film. Specifically, it is preferable to coat the surface of a silicone-based light-release PET film that has undergone a release treatment with an adhesive composition, heat-dry it, and then use a rubber roller to adhere the PO film to the adhesive composition layer in a manner that the corona-treated surface of the PO film is adhered to the exposed surface of the adhesive composition layer.

[0211] There are no particular limitations on the release liner; for example, release liners commonly used in adhesive applications can be used without restriction. Specifically, it is preferable to use a resin film that is the same as the resin film used in the aforementioned substrate, and from a processability perspective, it is preferable to use a resin film containing one or more resin films selected from PE, PP, and PET.

[0212] To impart easy peelability, a peeling process can be performed on the release sheet. Specifically, examples include peeling processes using silicone.

[0213] The thickness of the photocrosslinking adhesive layer is preferably 5–100 μm, more preferably 10–50 μm, and even more preferably 10–20 μm. When the thickness of the photocrosslinking adhesive layer is 5 μm or more, it exhibits sufficient adhesive properties and is easy to coat. When the thickness of the photocrosslinking adhesive layer is 100 μm or less, the generation of bubbles and solvent residue during heat drying can be suppressed.

[0214] [Uses of adhesive sheets]

[0215] Adhesive sheets can be used as re-peel adhesive sheets, for example, in the manufacture of electronic components. Specifically, re-peel adhesive sheets can be used as surface protectants to protect the surfaces of adhered objects during various processes in the manufacture of electronic components. Adhesive sheets can also be used in various processes in the manufacture of electronic components, where adhered objects are fixed, and after various processing steps, they are peeled off by UV (ultraviolet) irradiation. Therefore, adhesive sheets can be used as back-grinding tapes, dicing tapes, and dicing / chip bonding films in the processing of semiconductor wafers. Adhesive sheets can also be used as support tapes for fragile components such as ultra-thin glass substrates and easily warped components such as FPC substrates. In particular, adhesive sheets have excellent water resistance and sufficient adhesion to adhered objects, making them suitable for dicing tapes and dicing / chip bonding films.

[0216] [Cutting tape]

[0217] The cutting tape has a substrate layer and an adhesive layer formed by a thermosetting or photothermal curing agent of the adhesive composition.

[0218] The following describes an exemplary method of using adhesive sheets as dicing tape for wafers. Before the dicing process, the adhesive sheet is adhered to a wafer on which multiple components are formed. Next, the wafer is cut to separate (dic) individual components, forming component chips. Then, UV light is irradiated onto the adhesive sheets adhered to each component chip. As a result, UV light irradiates the photocrosslinking adhesive layer through the substrate of the adhesive sheet, causing the unsaturated bonds in the photocrosslinking adhesive to form a three-dimensional crosslinked structure and cure. Consequently, the adhesive strength of the adhesive layer decreases. Then, the adhesive sheet is peeled off from each component chip.

[0219] [Manufacturing method for cutting tape]

[0220] For cutting tape, it can be manufactured, for example, by forming a photocrosslinking adhesive layer on a substrate. The photocrosslinking adhesive layer can be formed, for example, using the same method as step (iv) described above.

[0221] The substrate is preferably a substrate made of a material suitable for the expansion process, and preferably a polyolefin film.

[0222] When using polyolefin films, heating during the formation of the photocrosslinking adhesive layer can sometimes be problematic from a heat resistance perspective. Therefore, the cut tape can be obtained by sequentially performing the following steps.

[0223] The steps of applying the adhesive composition onto a release sheet to obtain an adhesive composition layer (iv-1), and heat-curing the adhesive composition layer to obtain a photocrosslinkable adhesive layer (iv-2), and

[0224] The process of laminating the substrate onto the photocrosslinking adhesive layer (iv-3),

[0225] The obtained sheets are cured in an oven for a certain period of time as needed to form a cross-linked structure.

[0226] The thickness of the photocrosslinking adhesive layer is preferably 5–100 μm, more preferably 10–50 μm, and even more preferably 10–20 μm. When the thickness of the photocrosslinking adhesive layer is 5 μm or more, it exhibits sufficient adhesive properties and is easy to apply. When the thickness of the photocrosslinking adhesive layer is 100 μm or less, the generation of bubbles and solvent residue during heat drying can be suppressed. In particular, if the thickness of the photocrosslinking adhesive layer is 10–20 μm, sufficient peelability and slitting properties can be obtained.

[0227] [Integrated film for dicing / chip bonding]

[0228] The integrated dicing / chip bonding film sequentially comprises a substrate layer, an adhesive layer formed by a thermosetting or photothermal curing agent of an adhesive composition, and an adhesive layer.

[0229] [Manufacturing method of integrated dicing / chip bonding film]

[0230] For a dicing / chip bonding integrated film, it can be obtained, for example, by laminating a dicing tape with a chip bonding tape. For the dicing tape, it can be manufactured, for example, by the same method described above.

[0231] Methods for manufacturing integrated dicing / chip bonding films, for example, include the following steps.

[0232] The process of applying the adhesive composition onto a release sheet to obtain the adhesive composition layer (iv-1)

[0233] The process of heat-curing the adhesive composition to obtain a photocrosslinkable adhesive layer (iv-2)

[0234] The process of laminating a substrate onto an adhesive composition layer or a photocrosslinking adhesive layer to obtain a cutting tape (iv-3), and the process of laminating the cutting tape and the chip bonding tape (v).

[0235] The order of operations can be changed, except that operation (iv-1) is performed first and operation (v) is performed last. Operation (iv-3) can be performed between operations (iv-1) and operations (iv-2), or it can be performed after operations (iv-2).

[0236] The thickness of the photocrosslinking adhesive layer is preferably 5–100 μm, more preferably 10–50 μm, and even more preferably 10–20 μm. When the thickness of the photocrosslinking adhesive layer is 5 μm or more, it exhibits sufficient adhesive properties and is easy to apply. When the thickness of the photocrosslinking adhesive layer is 100 μm or less, the generation of bubbles and solvent residue during heat drying can be suppressed. In particular, if the thickness of the photocrosslinking adhesive layer is 10–20 μm, sufficient peelability and slitting properties can be obtained.

[0237] For process (v), for example, it can be performed by preparing a chip bonding tape and pressing it against a dicing tape. The chip bonding tape can also be obtained, for example, by coating an adhesive composition onto a release liner and allowing it to cure to form an adhesive layer. The bonding temperature is, for example, 30–50°C. The bonding pressure (wire pressure) is, for example, 0.1–20 kgf / cm.

[0238] As a variation of the manufacturing method for the integrated dicing / chip bonding film, the thermal curing of the adhesive composition can be performed in two separate steps, step (iv-2) and step (v). For example, after thermal curing in step (iv-2), the dicing tape and the chip bonding tape can be laminated in step (v), followed by curing to further thermally cure the photocrosslinking adhesive layer.

[0239] As a variation of the method for manufacturing the integrated dicing / chip bonding film, the release liner in step (iv-1) can be replaced with the chip bonding tape in step (v), and the formation of the photocrosslinking adhesive layer and the lamination of the dicing tape and the chip bonding tape can be performed in one step. In this case, the adhesive composition is applied to the adhesive layer of the chip bonding tape and thermally cured. The substrate is then laminated before or after thermal curing, thereby obtaining the integrated dicing / chip bonding film.

[0240] [Manufacturing method of cured products (photothermal cured products) of photocrosslinking adhesives]

[0241] Process (vi)

[0242] Cured products of photocrosslinking adhesives (also known as photothermal curing products) can be manufactured, for example, by a method comprising a step (vi) of forming a crosslinked structure by UV irradiation of the photocrosslinking adhesive.

[0243] Examples of light sources used for UV irradiation include high-pressure mercury lamps, ultra-high-pressure mercury lamps, carbon arc lamps, xenon lamps, metal halide lamps, chemical lamps, and black lights.

[0244] The preferred UV irradiation dose for photocrosslinking adhesives is 50–3,000 mJ / cm². 2 More preferably 100–600 mJ / cm 2 If the UV irradiation dose of the photocrosslinking adhesive is 50 mJ / cm² or higher, the crosslinking density of the photocrosslinking adhesive can be increased at a sufficiently fast curing speed through UV irradiation. Therefore, when using the photocrosslinking adhesive as an adhesive layer, the adhesive strength of the adhesive layer after UV irradiation can be significantly reduced. When using the photocrosslinking adhesive as a photoresist, the strength can be increased. Even when the UV irradiation dose of the photocrosslinking adhesive exceeds 3,000 mJ / cm², the crosslinking density remains high. 2 Furthermore, it was impossible to further increase the crosslinking density. Therefore, by setting the UV irradiation dose to 3,000 mJ / cm², the desired effect was not achieved. 2 The effects of UV irradiation on the adhered material can be mitigated, and cured products can be manufactured economically. Therefore, when photocrosslinking adhesives are used in adhesive sheets, peeling can be performed economically.

[0245] Example

[0246] The present invention will now be described in more detail through examples and comparative examples, but the present invention is not limited to the following examples.

[0247] The following lists the raw materials used in the synthesis of (meth)acrylic resins (A) and (cA). It should be noted that in Table 1, the SP value (J / cm²) is also listed in the compound name of the raw material monomers. 3 ) 1 / 2 ).

[0248] Raw material monomers:

[0249] 2-Hydroxyethyl Acrylate, Osaka Organic Chemical Industry Co., Ltd.

[0250] Styrene, Asahi Kasei Co., Ltd.

[0251] Isostearyl acrylate, Osaka Organic Chemical Industry Co., Ltd.

[0252] n-Butyl acrylate, Osaka Organic Chemical Industry Co., Ltd.

[0253] Cyclohexyl acrylate, Osaka Organic Chemical Industry Co., Ltd.

[0254] Methyl acrylate, Nippon Shokubai Co., Ltd.

[0255] Methyl methacrylate, Nippon Shokubai Co., Ltd.

[0256] Isopropylene methacrylate, Kurara Co., Ltd.

[0257] Free radical polymerization initiators:

[0258] 2,2'-Azobis(N-butyl-2-methylpropionamide), Fujifilm Wako Pure Chemical Industries, Ltd.

[0259] 2,2'-Azobis(isobutyronitrile), Fujifilm Wako Pure Chemical Industries, Ltd.

[0260] 2,2'-Azobis(2,4-dimethylvaleronitrile), Fujifilm Wako Pure Chemical Industries, Ltd.

[0261] RAFT agent:

[0262] Benzyldodecyl trithiocarbonate, Fujifilm Wako Pure Chemical Industries, Ltd.

[0263] 4-cyano-4-[(dodecylsulfanylthiocarbonyl)sulfanyl]pentanoic acid, Fujifilm Wako Pure Chemical Industries, Ltd.

[0264] bis[[4-[[ethyl-(2-acetoxyethyl)amino]carbonyl]phenyl]methyl] ester of trithiocarbonate, Fujifilm Wako Pure Chemical Co., Ltd.

[0265] 2-cyano-2-propyldodecyltrithiocarbonate, Fujifilm Wako Pure Chemical Industries, Ltd.

[0266] Alkene unsaturated compounds containing isocyanate groups (a):

[0267] Karenz (カレンズ) (trademark) MOI, ethyl 2-isocyanate methacrylate, RESONACAOI-VM (trademark), ethyl 2-isocyanate acrylate, RESONACAOI-VM Co., Ltd.

[0268] The following are examples of the synthesis of (meth)acrylic resins (A) and (cA). The weight-average molecular weight (Mw), molecular weight distribution (Mw / Mn), and hydroxyl value of (meth)acrylic resins (A) and (cA) were determined and calculated using the methods described above. The equivalent amount of olefinic unsaturated groups in (meth)acrylic resins (A) and (cA) was calculated from the feed amount as described above.

[0269] [Synthesis example 1]

[0270] (Process i-2)

[0271] In a reaction apparatus equipped with a stirrer, temperature controller, reflux condenser, dropping funnel, and thermometer, 25 moles of styrene, 0.118 parts by mass of benzyl dodecyl trithiocarbonate relative to a total of 100 parts by mass of the raw monomer group (mX) and (mY) and the isocyanate-containing olefinic unsaturated compound (a), 0.0417 parts by mass of 2,2'-azobis(N-butyl-2-methylpropionamide) relative to a total of 100 parts by mass of the raw monomer group (mX) and (mY) and the isocyanate-containing olefinic unsaturated compound (a), and butyl acetate as a solvent were added, so that the total concentration of the raw monomer group (mY), RAFT agent, and free radical polymerization initiator reached 80% by mass. The mixture was heated to 120°C and allowed to react for 14 hours.

[0272] (Process i-1)

[0273] Next, 58 moles of n-butyl acrylate, 17 moles of 2-hydroxyethyl acrylate, 0.0417 parts by mass of 2,2'-azobis(N-butyl-2-methylpropionamide) relative to a total of 100 parts by mass of the raw material monomer group (mX) and (mY) and the olefinic unsaturated compound (a) containing an isocyanate group, and butyl acetate as a solvent were added, so that the total concentration of the polymer obtained in step (i-2), the raw material monomer group (mX), and the free radical polymerization initiator added in step (i-1) was 80% by mass. The temperature was raised to 120°C and the reaction was allowed to proceed for 14 hours.

[0274] (Process ii)

[0275] Next, the reactants were cooled to room temperature and diluted with butyl acetate to achieve a copolymer concentration of 40% by mass in step (i-1). Then, the diluted reactants were heated to 55°C, and a mixture of 16 mol of ethyl 2-isocyanate acrylate and dibutyltin dilaurate as a carbamate catalyst was added dropwise through a dropping funnel. The amount of dibutyltin dilaurate was 0.06 parts by mass relative to a total of 100 parts by mass of the copolymer and the isocyanate-containing olefinic unsaturated compound (a) obtained in step (i-1). After the addition was complete, the reaction system was maintained at 60°C for 4 hours to allow the isocyanate groups to disappear. This yielded a liquid containing a (meth)acrylic resin (A1) with a weight-average molecular weight of 300,000, a molecular weight distribution of 2.6, an olefinic unsaturated group equivalent of 905 g / mol, and a hydroxyl value of 5.05 mg KOH / g, and a solid content of 40% by mass.

[0276] [Synthesis Examples 2 to 7]

[0277] Except for the composition shown in Table 1, the same operation as in Synthesis Example 1 was performed to obtain (meth)acrylic resins [A2] to [A7]. It should be noted that step (ii) was not performed in Synthesis Example 3.

[0278] [Comparative Synthesis Example 1]

[0279] (Process i-1)

[0280] In a reaction apparatus equipped with a stirrer, temperature controller, reflux condenser, dropping funnel, and thermometer, 6 moles of n-butyl acrylate, 16 moles of 2-hydroxyethyl acrylate, 0.260 parts by mass of bis[[4-[[ethyl-(2-acetoxyethyl)amino]carbonyl]phenyl]methyl trithiocarbonate relative to a total of 100 parts by mass of the starting monomers (mX) and (mY) and the isocyanate-containing olefinic unsaturated compound (a), 0.0160 parts by mass of 2,2'-azobis(2,4-dimethylpentanonitrile) relative to a total of 100 parts by mass of the starting monomers (mX) and (mY) and the isocyanate-containing olefinic unsaturated compound (a), and ethyl acetate as solvent were added, such that the total concentration of the starting monomers (mX), RAFT agent, and free radical polymerization initiator was 50% by mass. The mixture was heated to 60°C and reacted for 7 hours.

[0281] (Process i-2)

[0282] Next, 78 moles of n-butyl acrylate, 0.0160 parts by mass of 2,2'-azobis(2,4-dimethylpentanones) relative to a total of 100 parts by mass of the raw material monomer group (mX) and (mY) and the olefinic unsaturated compound (a) containing an isocyanate group, and ethyl acetate as a solvent were added, so that the total concentration of the copolymer obtained in step (i-1), the raw material monomer group (mY), and the free radical polymerization initiator added in step (i-2) was 50% by mass. The temperature was raised to 60°C and the reaction was allowed to proceed for 14 hours.

[0283] (Process ii)

[0284] Next, the reactants were cooled to room temperature and diluted with ethyl acetate to achieve a copolymer concentration of 40% by mass in step (i-2). Then, the diluted reactants were heated to 55°C, and a mixture of 13 moles of ethyl 2-isocyanate methacrylate and dibutyltin dilaurate as a carbamate catalyst was added dropwise through a dropping funnel. The amount of dibutyltin dilaurate was 0.06 parts by mass relative to a total of 100 parts by mass of the copolymer obtained in step (i-2) and the isocyanate-containing olefinic unsaturated compound (a). After the addition was complete, the reaction system was maintained at 60°C for 4 hours to allow the isocyanate groups to disappear. This yielded a liquid containing an XYX type (meth)acrylic resin (cAl) with a weight-average molecular weight of 300,000, a molecular weight distribution of 2.4, an olefinic unsaturated group equivalent of 1109 g / mol, and a hydroxyl value of 11.46 mg KOH / g, and a solid content of 40% by mass.

[0285] [Comparative Synthesis Example 2]

[0286] Except for using the composition shown in Table 1, the same operation as in Comparative Synthesis Example 1 was performed to obtain an XYX type (meth)acrylic resin (cA2).

[0287] [Comparative Synthesis Example 3]

[0288] (Process i-1)

[0289] In a reaction apparatus equipped with a stirrer, temperature controller, reflux condenser, dropping funnel, and thermometer, 18 moles of styrene, 10 moles of 2-hydroxyethyl acrylate, 0.156 parts by mass of 4-cyano-4-[(dodecylthioalkylthiocarbonyl)thioalkyl]pentanoic acid relative to a total of 100 parts by mass of the starting monomers (mX) and (mY) and the isocyanate-containing olefinic unsaturated compound (a), 0.0405 parts by mass of 2,2'-azobis(2,4-dimethylpentanonitrile) relative to a total of 100 parts by mass of the starting monomers (mX) and (mY) and the isocyanate-containing olefinic unsaturated compound (a), and butyl acetate as a solvent were added, such that the total concentration of the starting monomers (mX), RAFT agent, and free radical polymerization initiator was 80% by mass. The mixture was heated to 120°C and reacted for 14 hours.

[0290] (Process i-2)

[0291] Next, 62 moles of n-butyl acrylate, 10 moles of 2-hydroxyethyl acrylate, 0.0405 parts by mass of 2,2'-azobis(2,4-dimethylpentanones) relative to a total of 100 parts by mass of the raw material monomer groups (mX) and (mY) and the olefinic unsaturated compound (a) containing an isocyanate group, and butyl acetate as a solvent were added, so that the total concentration of the copolymer obtained in step (i-1), the raw material monomer group (mY), and the free radical polymerization initiator added in step (i-2) was 80% by mass. The temperature was raised to 120°C and the reaction was allowed to proceed for 14 hours.

[0292] (Process ii)

[0293] Next, the reactants were cooled to room temperature and diluted with butyl acetate to achieve a copolymer concentration of 40% by mass in step (i-2). Then, the diluted reactants were heated to 55°C, and a mixture of 18 mol of ethyl 2-isocyanate acrylate and dibutyltin dilaurate as a carbamate catalyst was added dropwise through a dropping funnel. The amount of dibutyltin dilaurate was 0.06 parts by mass relative to a total of 100 parts by mass of the copolymer obtained in step (i-2) and the isocyanate-containing olefinic unsaturated compound (a). After the addition was complete, the reaction system was maintained at 60°C for 4 hours to allow the isocyanate groups to disappear. This yielded a liquid containing a (meth)acrylic resin (cA3) with a weight-average molecular weight of 250,000, a molecular weight distribution of 2.4, an olefinic unsaturated group equivalent of 833 g / mol, and a hydroxyl value of 9.41 mg KOH / g, and a solid content of 40% by mass.

[0294] [Comparative Synthesis Example 4]

[0295] (Process i-1)

[0296] In a reaction vessel, 63 mol of n-butyl acrylate, 17 mol of 2-hydroxyethyl acrylate, 20 mol of isostearate acrylate, 0.135 parts by mass of benzyl dodecyl trithiocarbonate relative to 100 parts by mass of the total of the starting monomer group (mX) and the isocyanate-containing olefinic unsaturated compound (a), 0.0563 parts by mass of 2,2'-azobis(isobutyronitrile) relative to 100 parts by mass of the total of the starting monomer group (mX) and the isocyanate-containing olefinic unsaturated compound (a), and butyl acetate as a solvent were added, such that the total concentration of the starting monomer group (mX), RAFT agent, and free radical polymerization initiator was 80% by mass. The mixture was heated to 120°C and allowed to react for 14 hours.

[0297] (Process ii)

[0298] Next, the reactants were cooled to room temperature and diluted with butyl acetate to achieve a copolymer concentration of 40% by mass in step (i-1). Then, the diluted reactants were heated to 55°C, and a mixture of 15 moles of ethyl 2-isocyanate acrylate and dibutyltin dilaurate as a carbamate catalyst was added dropwise through a dropping funnel. The amount of dibutyltin dilaurate was 0.06 parts by mass relative to a total of 100 parts by mass of the copolymer obtained in step (i-1) and the isocyanate-containing olefinic unsaturated compound (a). After the addition was complete, the reaction system was maintained at 60°C for 4 hours to allow the isocyanate groups to disappear. This yielded a liquid containing a (meth)acrylic resin (cA4) with a weight-average molecular weight of 280,000, a molecular weight distribution of 2.1, an olefinic unsaturated group equivalent of 1221 g / mol, and a hydroxyl value of 5.04 mg KOH / g, and a solid content of 40% by mass.

[0299] [Comparative Synthesis Example 5]

[0300] (Process i-1)

[0301] Butyl acetate was added as a solvent to the reaction vessel to achieve a total concentration of 60% by mass for the starting monomer group (mX) and the free radical polymerization initiator. A mixture was prepared by mixing 63 mol of n-butyl acrylate, 17 mol of 2-hydroxyethyl acrylate, 20 mol of isostearate acrylate, and 0.297 parts by mass of 2,2'-azobis(isobutyronitrile) relative to a total of 100 parts by mass of the starting monomer group (mX) and the isocyanate-containing olefinic unsaturated compound (a). The butyl acetate in the reaction vessel was heated to 80°C, and the above mixture was added dropwise over 3 hours. After the addition was completed, the reaction was continued at 80°C for 4 hours.

[0302] (Process ii)

[0303] Next, the reactants were cooled to room temperature and diluted with butyl acetate to achieve a copolymer concentration of 40% by mass in step (i-1). Then, the diluted reactants were heated to 55°C, and a mixture of 15 moles of ethyl 2-isocyanate acrylate and dibutyltin dilaurate as a carbamate catalyst was added dropwise through a dropping funnel. The amount of dibutyltin dilaurate was 0.06 parts by mass relative to a total of 100 parts by mass of the copolymer and the isocyanate-containing olefinic unsaturated compound (a) obtained in step (i-1). After the addition was complete, the reaction system was maintained at 60°C for 4 hours to allow the isocyanate groups to disappear. This yielded a liquid containing a (meth)acrylic resin (cA5) with a weight-average molecular weight of 320,000, a molecular weight distribution of 4.2, an olefinic unsaturated group equivalent of 1221 g / mol, and a hydroxyl value of 5.04 mg KOH / g, and a solid content of 40% by mass.

[0304]

[0305]

[0306]

[0307]

[0308] The following lists the raw materials used to prepare the adhesive composition.

[0309] Photopolymerization initiator (B):

[0310] TPO: 2,4,6-Trimethylbenzoyldiphenylphosphine oxide (BASF, trade name: L-TPO)

[0311] Ilgacul 500: A mixture of 1-hydroxycyclohexylphenyl ketone and benzophenone (BASF Corporation, trade name: Ilgacul 500)

[0312] Crosslinking agent (C)

[0313] Takenet: Toluene diisocyanate adduct of trimethylolpropane (Mitsui Chemicals Co., Ltd., trade name: Takenet D-101E)

[0314] L-55E: Toluene diisocyanate adduct of trimethylolpropane (Higashi Sou Co., Ltd., trade name: Coronato L-55E).

[0315] L-45E: Toluene diisocyanate adduct of trimethylolpropane (Higashi Sou Co., Ltd., trade name: Coronato L-45E).

[0316] [Preparation of Adhesive Compositions]

[0317] Ethyl acetate was added as a diluent to the liquids containing (meth)acrylic resins (A1) to (A7) and (cA1) to (cA5) obtained in Synthetic Examples 1 to 7 and Comparative Synthetic Examples 1 to 5, and the content of (meth)acrylic resins (A1) to (A7) and (cA1) to (cA5) was adjusted to 30% by mass, respectively. Using this liquid, an adhesive composition was obtained by the method shown below.

[0318] In a room where active radiation is blocked, the (meth)acrylic resin (A) or (cA), photopolymerization initiator (B) and crosslinking agent (C) shown in Table 2 are added to plastic containers in the amounts (parts by mass) shown in Table 2 and stirred to obtain adhesive compositions (B1) to (B7) and (cB1) to (cB5).

[0319] [Example 1] Fabrication of adhesive sheet

[0320] As a release sheet, a silicone-based light-release PET film (Toyobo Co., Ltd., trade name: E7006, thickness 25 μm) was prepared. For the surface that had undergone release treatment, an adhesive composition (B1) was applied using a coater to a heat-cured thickness of 11 μm. The film was then heated and dried at 110°C for 2 minutes to form an adhesive composition layer. Next, a PO film with a thickness of 90 μm was prepared as a sheet substrate. The PO film was adhered to the adhesive composition layer using a rubber roller, with the corona-treated side of the PO film bonded to the exposed side of the adhesive composition layer. The adhesive composition layer was then cured in an oven at 40°C for 3 days to crosslink and obtain the adhesive sheet of Example 1.

[0321] [Examples 2-7 and Comparative Examples 1-5] Fabrication of Adhesive Sheets

[0322] Adhesive compositions [B2] to [B7] and [cB1] to [cB5] were used to replace adhesive composition [B1], and the thickness of the adhesive composition layer after heat curing was as shown in Table 2. Otherwise, the same operation as in Example 1 was performed to obtain adhesive sheets of Examples 2 to 7 and Comparative Examples 1 to 5.

[0323] [Adhesion Evaluation]

[0324] (1) Determination of initial adhesive strength (180° peel strength)

[0325] As described below, the adhesion strength of the adhesive sheets to the wafers of the Examples and Comparative Examples was evaluated by measuring the 180° peel strength. Samples with a width of 25 mm and a length of 100 mm were cut from the adhesive sheets of Examples 1-7 and Comparative Examples 1-5. The silicone-based light-peel PET film was peeled off to expose the adhesive layer, and the sample was then attached to a test virtual wafer (AS ONE Co., Ltd.) using a rubber roller. The sample was pressed using an autoclave (TAC-200, Sakura Seiki Co., Ltd.) to obtain the adhesive strength test sample. The peel strength of the adhesive sheet to the wafer was measured using a tensile testing machine (TAXT2i, Stable Micro Systems Co., Ltd.) to determine the initial adhesion strength. The test conditions were set as a peel angle of 180° and a tensile speed of 5 mm / sec. It should be noted that the sample storage and peel strength measurement were performed at a temperature of 23°C and a relative humidity of 40%. The results are shown in Table 2.

[0326] (2) Determination of adhesive strength (180° peel strength) after impregnation

[0327] Samples for adhesive force testing were prepared using the same method as for the determination of initial adhesive force (180° peel strength) in (1). The obtained samples were immersed in ion-exchanged water and left to stand in the dark for 3 hours at a temperature of 23°C and a relative humidity of 40%. After removing the immersed samples and removing excess water, the peel strength of the adhesive sheet to the wafer was measured using the same method as for the determination of initial adhesive force (180° peel strength) in (1), and this was determined as the adhesive force after immersion. Based on the measurement results, the rate of change of adhesive force was calculated using the following formula. The results are shown in Table 2.

[0328] Adhesive force change rate (%) = ((adhesive force after impregnation) - (initial adhesive force) / (initial adhesive force)) × 100

[0329] (3) Determination of adhesive strength (30° peel strength) after UV irradiation

[0330] The adhesive strength test sample was prepared using the same method as for the initial adhesive strength (180° peel strength) test in (1). The substrate side of the adhesive sheet of the obtained sample was irradiated at a dose of 300 mJ / cm². 2 The samples were irradiated with ultraviolet light (UV) under the specified conditions to obtain samples for measuring the adhesive strength after UV irradiation. UV irradiation was performed using a conveyor belt type UV irradiation device (Igravex Co., Ltd., 2KW lamp, 80W / cm). Then, except that the peel angle was changed to 30°, the peel strength of the adhesive sheet to the wafer was measured using the same method as the initial adhesive strength (180° peel strength) measurement, and the adhesive strength after UV irradiation was determined. The results are shown in Table 2.

[0331]

[0332]

[0333] [Fabrication of integrated dicing / chip bonding film]

[0334] The cover film on one side of the chip bonding film (FH-D25T-50, RESONAC Co., Ltd.), which is protected by a cover film on both sides of the adhesive layer, is peeled off to expose the adhesive layer. This adhesive layer is then bonded to the adhesive layer of the bonding sheets of Examples 1-7 and Comparative Examples 1-5, where the adhesive layer has been exposed after the light-peel PET film has been peeled off. After being left at room temperature for 1 day, a dicing / chip bonding integrated film is obtained.

[0335] [Process Evaluation]

[0336] (1) Blade cutting test (cutting performance)

[0337] Using a dicing / chip bonding integrated film, dicing semiconductor wafers is performed according to the following guidelines. Count the number of chips that detach from the dicing / chip bonding integrated film and scatter after dicing (total number: 400), and calculate the chip scattering rate (%) as an evaluation of dicing performance. Therefore, the closer the chip scattering rate is to 0%, the better the dicing performance.

[0338] First, the semiconductor wafer (8-inch diameter, 0.6mm thickness, silicon mirror wafer) was back-side ground to obtain a mirror wafer with a thickness of 0.2mm. Next, the mirror wafers were rolled and bonded together at 70°C on the adhesive layer exposed after peeling off the cover film from the dicing / chip bonding integrated film. Then, the mirror wafers were diced. The mirror wafers were fully diced to form a 1.0mm square chip size. The bonding and dicing conditions are described below.

[0339] Semiconductor wafer polishing conditions

[0340] Grinding equipment: Product name DFG-8560 (DISCO Co., Ltd.)

[0341] Semiconductor wafers: 8-inch diameter (backside ground to a thickness of 0.6mm to 0.2mm)

[0342] <Fitness Conditions>

[0343] Mounting device: Product name MA-3000III (Nitto Seiki Co., Ltd.)

[0344] Application speed: 10mm / min

[0345] Adhesion pressure: 0.15MPa

[0346] Workbench temperature during attachment: 70℃

[0347] <Cutting Conditions>

[0348] Cutting device: Product name DFD-6361 (DISCO Co., Ltd.)

[0349] Cutting ring: 2-8-1 (DISCO Co., Ltd.)

[0350] Cutting speed: 30mm / second

[0351] Cutting blade: Z1: 203O-SE 27HCDD (DISCO Co., Ltd.)

[0352] Z2: 203O-S27HCBB (DISCO Co., Ltd.)

[0353] Cutting blade speed: Z1: 40000 r / min

[0354] Z2: 45000r / min

[0355] Cutting method: stepped cutting

[0356] Chip size: 1.0mm square

[0357] Cutting water supply rate: 2.0L / min

[0358] <Evaluation Criteria for Cutting Performance>

[0359] S: Chip scattering rate is 0% or higher and less than 5%.

[0360] A: The chip scattering rate is above 5% but less than 10%.

[0361] B: The chip scattering rate is above 10% but less than 20%.

[0362] C: The chip scattering rate is over 20%.

[0363] (2) Pickup test (pickup performance)

[0364] After the mirror wafer is cut as described above, the semiconductor chips are picked up. Picking up is performed after the adhesive layer is irradiated with ultraviolet light. The irradiation conditions are as follows. After irradiation with ultraviolet light, a needle is used to lift the semiconductor chip with adhesive attached, obtained from the cutting tape side of the dicing / chip bonding integrated film, and pick it up from the adhesive layer. At this time, the success rate (%) of picking up the semiconductor chips (total number: 400) is calculated to evaluate the pickability. Therefore, the closer the pickability rate is to 100%, the better the pickability. It should be noted that chips that are scattered are not included in the base number (parent number). The picking conditions are as follows.

[0365] <Ultraviolet radiation conditions>

[0366] Ultraviolet (UV) irradiation device: High-pressure mercury lamp

[0367] Cumulative ultraviolet radiation: 500 mJ / cm2

[0368] Output: 75W

[0369] Irradiation intensity: 150mW / cm2

[0370] It should be noted that the ultraviolet irradiation is performed from the surface of the substrate side of the cut tape.

[0371] <Pickup Conditions>

[0372] Pickup device: Trade name SPA-300 (Shinkawa Co., Ltd.)

[0373] Number of needles picked up: 1

[0374] Needle lifting speed: 20mm / second

[0375] Needle tip volume: 500μm

[0376] Pickup time: 1 second

[0377] Tape expansion during cutting: 3mm

[0378] <Evaluation Criteria>

[0379] S: The success rate of picking up items is above 95% and below 100%.

[0380] A: The success rate of picking up the item is over 80% but less than 95%.

[0381] B: The success rate of picking up the item is above 60% but less than 80%.

[0382] C: The success rate of picking up the item is less than 60%.

[0383] The adhesive sheets of Examples 1-7 exhibited low rates of change in adhesive force and excellent water resistance. The cut / chip bonding integrated films fabricated using the adhesive sheets of Examples 1-7 showed good results in both blade cutting and pick-up tests.

[0384] Industrial availability

[0385] According to this disclosure, an adhesive composition can be provided that provides an adhesive sheet with high adhesive strength and excellent water resistance to cutting water, and whose adhesive strength is significantly reduced by ultraviolet irradiation. The adhesive layer formed from this adhesive composition is preferably used as a peel-off adhesive sheet, particularly as an adhesive layer for cutting tapes.

Claims

1. An adhesive composition comprising (meth)acrylic resin A, photopolymerization initiator B, and crosslinking agent C; The (meth)acrylic resin A is a diblock copolymer composed of X-blocks and Y-blocks. The structural unit ratio of the X-block to the Y-block is 56:44 to 81:19 in molar ratio. The X block comprises a structural unit M-1 having a hydroxyl group and a structural unit M-2 having an olefinic unsaturated group. The Y-segment has an SP value of 20 (J / cm). 3 ) 1 / 2 The structural unit M-3 of the following olefinic unsaturated compound (m-3) is a structural unit without an olefinic unsaturated group and a hydroxyl group, and optionally one or more structural units selected from structural units M-1 having a hydroxyl group and structural units M-2 having an olefinic unsaturated group. At least one of the structural units M-1, M-2, and M-3 has a structure derived from (meth)acryloyloxy. When the total number of structural units in the X block is set to 100 mol%, the total proportion of the structural unit M-1 with hydroxyl groups and the structural unit M-2 with olefinic unsaturated groups in the X block is 18-95 mol%. When the total number of structural units in the Y-block is set to 100 mol%, the total proportion of the structural unit M-1 with hydroxyl groups and the structural unit M-2 with olefinic unsaturated groups in the Y-block is 0~17 mol%. When the total number of structural units in the X block is set to 100 mol%, the proportion of the hydroxyl-containing structural unit M-1 in the X block is 1.5 to 35 mol%. When the total number of structural units in the X-block is set to 100 mol%, the proportion of the structural unit M-2 with the olefinic unsaturated group in the X-block is 15-60 mol%. When the total number of structural units in the Y-block is set to 100 mol%, the proportion of the hydroxyl-containing structural unit M-1 in the Y-block is 15 mol% or less. When the total number of structural units in the Y-block is set to 100 mol%, the proportion of the structural unit M-2 with olefinic unsaturated groups in the Y-block is 15 mol% or less. When the total number of structural units in the Y-block is set to 100 mol%, the SP-derived value of the Y-block is 20 (J / cm). 3 ) 1 / 2 The proportion of structural unit M-3 in the following olefinic unsaturated compounds m-3 is 92.9~100 moles.

2. The adhesive composition according to claim 1, wherein the structural unit M-2 having an olefinic unsaturated group in the X block is a structural unit formed by adding an isocyanate-containing olefinic unsaturated compound a to the hydroxyl group of the structural unit derived from the structural unit of the olefinic unsaturated compound m-1 having a hydroxyl group.

3. The adhesive composition according to claim 1, wherein the Y-block has a source SP value of 20 (J / cm). 3 ) 1 / 2 The structural unit M-3 of the following olefinic unsaturated compound m-3 is derived from the structural unit of a straight-chain or branched (meth)acrylate ester with 6 to 30 carbon atoms selected from alkyl groups, (meth)acrylate esters with an alicyclic skeleton, and styrene monomers.

4. The adhesive composition according to claim 1, wherein the Y-block has a structural unit derived from styrene.

5. The adhesive composition according to claim 1, wherein the X block further comprises a structural unit of a straight-chain or branched (meth)acrylate alkyl ester having 1 to 5 carbon atoms derived from an alkyl group.

6. The adhesive composition according to claim 1, wherein the (meth)acrylic resin A has a weight-average molecular weight of 1 × 10⁻⁶. 4 ~200×10 4 .

7. The adhesive composition according to claim 1, wherein the olefinic unsaturated group equivalent of the (meth)acrylic resin A is 100~5000 g / mol.

8. The adhesive composition according to claim 1, wherein the hydroxyl value of the (meth)acrylic resin A is 0.01~50 mgKOH / g.

9. An adhesive sheet having a substrate layer and an adhesive layer formed from a thermosetting or photothermal curing agent of the adhesive composition according to any one of claims 1 to 8.

10. A cutting tape having a substrate layer and an adhesive layer formed from a thermosetting or photocurable product of the adhesive composition according to any one of claims 1 to 8.

11. A dicing / chip bonding integrated film, comprising in sequence a substrate layer, an adhesive layer formed of a thermosetting or photothermal curing material of the adhesive composition according to any one of claims 1 to 8, and an adhesive layer.

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