TWI752845B - Thermal peel adhesive tape - Google Patents

Abstract

In the present invention, the maximum expansion temperature of the heat-expandable particles in the heat-peelable adhesive tape having the heat-expandable adhesive layer including the adhesive component and the heat-expandable particles is set to 170°C or higher, and the dynamic viscoelasticity of the adhesive component is measured ( In the temperature range of -60°C to 300°C, heating rate of 10°C/min, frequency of 10 Hz), (1) the tanδ at the maximum expansion temperature of the thermally expandable particles is set to 0.120 or less, and (2) the tanδ at 170°C is set. The storage modulus G' is set to be more than 30,000 Pa, thereby providing a heat-peelable adhesive tape, which can be used well in the long-term pressing step at high temperature or normal temperature, and if used in the pressing step, further When heated, the adhesion of the adhesive layer is significantly reduced, and it can be easily peeled off without leaving paste on the adherend.

Description

Thermal peel adhesive tape

The present invention relates to a heat-peelable adhesive tape, which can be favorably used in a pressing step at a high temperature or a long time at normal temperature in various manufacturing steps including the manufacturing step of electronic parts or semiconductor parts, and if applied If the adhesive tape is used in the pressing step and then heated, the adhesiveness of the adhesive tape is significantly reduced, and the adhesive tape can be easily peeled off without leaving any paste.

Generally, adhesive tapes with high heat resistance are widely used for manufacturing steps of electronic parts and semiconductor parts. High heat-resistance adhesive tapes are widely used for temporary fixation of components or parts, fixation during transportation, reinforcement, protection, shielding, resin sealing, etc. This kind of application requires the adhesive tape to have a sufficiently high adhesive force to the adherend when in use, and it can be easily peeled off after use without leaving any paste.

In recent years, various end products including electronic equipment are required to be thinned and miniaturized, and accordingly, the parts have been continuously thinned and miniaturized. When it is difficult to process thin parts with low rigidity, an adhesive tape is sometimes used to improve workability. For example, in the manufacturing process of thin substrates such as thin electronic circuit substrates, the adhesive surface on one side of the double-sided adhesive tape is attached and fixed to a conveying plate with high rigidity, and the thin substrate is attached to the adhesive surface on the opposite side. It can improve the workability of parts mounting or component processing on thin substrates. The processing of such a member includes, for example, a hot pressing step when a semiconductor wafer is placed on a thin substrate and sealed with a resin. The thin substrate, double-sided tape, and conveying plate obtained from the processing or mounting of the completed components are separated from each other, and the conveying plate is reused for the processing of the thin substrate if necessary. In the temporary fixation of the thin substrate by using the adhesive tape, a sufficiently strong adhesiveness is required in the processing step. On the other hand, if the load applied to the thin substrate is large when the adhesive tape is peeled off, the thin substrate will be damaged, so it is required that the adhesiveness of the adhesive tape be as low as possible when peeling off the adhesive tape. Moreover, regarding the material of a conveyance board, glass has been used in the past. However, the conveying plate made of glass may be easily deformed in a high temperature environment, or the linear expansion coefficient may be significantly different from that of the product. Therefore, when it is used in a process with a more severe temperature than before, as the material of the conveying plate, stainless steel (SUS), metal such as aluminum plate and copper plate, silicon, copper foil laminated plate, etc. are frequently used.

In the production steps of such thin substrates, instead of using a transfer plate, a single-sided adhesive tape using a substrate with high rigidity (such as a resin film of 50 μm to 125 μm) is attached to the thin substrate, which can Improves workability when mounting parts or machining components on thin substrates. After the processing or installation of the components is completed, the adhesive tape is peeled off from the thin substrate. Even in the case of this method of use, a sufficiently strong adhesiveness is required in the processing steps, and on the other hand, the adhesiveness as low as possible is required when peeling off the adhesive tape.

In addition, in recent years, the heat resistance of electronic components and semiconductor components has been higher than that of the previous ones, centered on in-vehicle applications. Along with this, higher heat resistance is also required for materials constituting parts, such as resins for sealing chips in semiconductor packages. Resins with higher heat resistance usually require higher heating temperature and longer heating time for curing. Therefore, high heat resistance is also required for the adhesive tape used in the step of curing such a high heat resistance resin.

Previously, Patent Documents 1 to 6 disclose an adhesive tape which has sufficient adhesiveness from the initial stage of being attached to the adherend until it is used in the manufacturing process, but by applying some external stimulus after use, Adhesion is significantly reduced.

Patent Document 1 discloses a photosensitive adhesive tape and a method for producing the same. Although the photosensitive adhesive tape exhibits excellent initial adhesion properties to semiconductor substrates or film substrates and is excellent in adhesiveness during production steps such as dicing, By irradiating ultraviolet rays, the photosensitive adhesive hardens, and the adhesive force is significantly reduced. However, since the photoreactive component contained in the adhesive whose adhesive force is reduced by ultraviolet irradiation is generally low in heat resistance, it may not be suitable for use in a high-temperature manufacturing process. Furthermore, such a photosensitive adhesive cannot be used for a transfer plate made of an opaque material such as metal or silicon as described above.

Patent Document 2 discloses a heat-resistant adhesive tape which is excellent in preventing leakage of resin in the sealing step, and prevents peeling or breakage of the molded sealing resin or residue of paste when peeling the heat-resistant adhesive tape , so that the yield can be improved. The adhesive tape disclosed in Patent Document 2 has an ultraviolet-curable adhesive layer, and after irradiating the adhesive layer with ultraviolet rays and heating at 200° C. for 1 hour, the adhesive force measured in accordance with JISZ0237 is in the range of 1 N/19 m or less. . However, the adhesive tape disclosed in Patent Document 2 is used on the premise that ultraviolet rays are irradiated before the sealing step (ie, the heating step) by the sealing resin, so that the adhesive layer induces UV rays. A hardening reaction, thereby reducing adhesion, is followed by resin injection and heat hardening. That is, Patent Document 2 does not mention anything about applying an external stimulus after the heating step to facilitate the peeling of the adhesive tape. This adhesive tape, like the adhesive tape of Patent Document 1, cannot be used for a transfer plate made of an opaque material such as metal or silicon.

Patent Documents 3 to 6 disclose a heat-peelable pressure-sensitive adhesive sheet in which, when heated to a predetermined temperature, the heat-expandable microspheres contained in the heat-expandable pressure-sensitive adhesive layer are foamed, and the adhesive force is remarkably lowered. The heat-peelable pressure-sensitive adhesive sheets disclosed in these patent documents heat the pressure-sensitive adhesive layer (heat-expandable pressure-sensitive adhesive layer) containing heat-expandable microspheres as a foaming agent after achieving the purpose of adhering articles including the adherend. , whereby the adhesive force is reduced, and the adherend can be easily separated from the heat-peelable adhesive sheet. The main reason for the decrease in the adhesive force of the adhesive layer is that the adhesive layer foams or expands due to heating, the surface of the adhesive layer becomes uneven, and the bonding area with the adherend decreases. The heat-peelable adhesive sheets disclosed in these patent documents are not premised on the use in the high temperature heating step for a long time, and the patent documents do not mention anything about the use in the high temperature or normal temperature and long time pressing step after use The technology of further heating to make it easy to peel off. If these thermal foaming peelable adhesive tapes are used in the high temperature and long time pressing step, the following problems may occur: • The heat-expandable particles are foamed during pressurization, and the adhesion with the adherend in the step is reduced; • When the heat-expandable particles are expanded under pressure, the dimensions of the heat-foaming peel-off adhesive tape itself or the dimensions specified by the heat-foaming peel-off adhesive tape change, resulting in poor processing; • Thermal deterioration of the adhesive component, reduction in cohesion, and paste residue on the adherend after foaming and peeling.

Patent Document 6 discloses a heat-peelable adhesive tape capable of preventing positional displacement of the thermally expandable adhesive layer due to deformation of the adhesive during the lamination pressing step of the green sheet in the manufacturing step of the ceramic capacitor. It is considered that such a heat-peelable pressure-sensitive adhesive tape can be suitably used for preventing positional displacement in a pressing step at room temperature for a short time. However, Patent Document 6 does not mention anything about the foaming releasability of the adhesive layer after being used in a long-time pressing step at high temperature or normal temperature, or the paste residue on the adherend after peeling, the high temperature addition Contents such as foam suppression of heat-expandable particles in the pressing step. In addition, when the heat-expandable particles used in Examples 1 to 3 of Patent Document 6 start to expand at 120°C, for example, when used in a step such as hot-pressing at 170°C for 1 hour, it is assumed that hot-pressing will occur. When foaming occurs. [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2001-139905 [Patent Document 2] Japanese Patent Laid-Open No. 2012-46763 [Patent Document 3] Japanese Patent Laid-Open No. 11-166164 [Patent Document 4] Japanese Patent Laid-Open No. 2007-246823 [Patent Document 5] Japanese Patent Laid-Open No. 2016-155919 [Patent Document 6] International Publication No. 2005/087887

(The problem that the invention intends to solve)

An object of the present invention is to provide a heat-peelable adhesive tape, which is an adhesive tape used in the pressing step of the adherend in various manufacturing steps including the manufacturing step of electronic parts or semiconductor parts, which can be satisfactorily used at high temperatures Or use it in the long-term pressing step at room temperature, and if it is further heated after the pressing step, the adhesiveness of the adhesive layer will be significantly reduced, and it can be easily peeled off without leaving paste on the adherend. (Technical means to solve problems)

In order to achieve the above-mentioned object, the inventors of the present invention have conducted intensive studies, and as a result found that, by making a heat-peelable pressure-sensitive adhesive tape having a heat-expandable pressure-sensitive adhesive layer containing an adhesive component and heat-expandable particles to satisfy the following requirements, the It is very effective in terms of adaptability when used in a long-term pressing step, easy peeling or paste residue when further heating, and foaming suppression of heat-expandable particles during high-temperature pressing. • The amount of heat-expandable particles added to the adhesive component is within a predetermined range. • The maximum expansion temperature of thermally expandable particles is within a predetermined range. • Each parameter in the dynamic viscoelasticity measurement of the adhesive composition is within a predetermined range. The present inventors completed the present invention based on the above-mentioned new findings.

That is, the heat-peelable adhesive tape of the present invention has a heat-expandable adhesive layer containing an adhesive component and heat-expandable particles, wherein the heat-expandable adhesive layer contains 4 parts by mass relative to 100 parts by mass of the adhesive component. The above-mentioned heat-expandable particles, the maximum expansion temperature of the above-mentioned heat-expandable particles is 170°C or higher, and the dynamic viscoelasticity of the above-mentioned adhesive component is measured (temperature range -60°C to 300°C, heating rate 10°C/min, frequency 10°C) Hz), (1) tanδ at the maximum expansion temperature of the thermally expandable particles is 0.120 or less, and (2) The storage modulus G' at 170°C is 30,000 Pa or more. The hot-pressing method of the adherend of the present invention is a hot-pressing method of the adherend having a temporarily fixed heat-peelable adhesive tape, which is characterized by comprising: The step of temporarily fixing the above-mentioned adhesive tape to the adherend; The step of heat-pressing the above-mentioned adherend temporarily fixed with the adhesive tape; the step of heating the adhesive tape temporarily fixed to the above-mentioned hot-pressed adherend to a temperature for peeling; and The step of peeling the above-mentioned adhesive tape heated to the temperature for peeling from the above-mentioned adherend. (Compared to the efficacy of the prior art)

The heat-peelable adhesive tape of the present invention has a heat-expandable adhesive layer including an adhesive component and heat-expandable particles, the heat-expandable particles have a maximum expansion temperature in a predetermined range, and has a dynamic viscoelasticity measurement under a predetermined condition of the adhesive component. established properties. By virtue of the constitution and physical properties of these thermally expandable adhesive layers, a thermally peelable adhesive tape can be provided, which can suppress the foaming of the thermally expandable particles contained in the adhesive layer during a long-time pressing step at high temperature or normal temperature, By further heating after the pressing step, the adhesiveness of the heat-expandable adhesive layer is significantly reduced, and the paste is less likely to remain on the adherend.

The heat-peelable adhesive tape of the present invention has at least a heat-expandable adhesive layer. [Thermal Expansion Adhesive Layer] The thermally expandable adhesive layer contains at least an adhesive component for imparting adhesiveness and thermally expandable particles (foaming agent) for imparting thermally expandable properties. The heat-expandable adhesive layer contains 4 parts by mass or more of heat-expandable particles with respect to 100 parts by mass of the adhesive component. The maximum expansion temperature of the heat-expandable particles is 170°C or higher, and the adhesive component in the dynamic viscoelasticity measurement (temperature range -60°C to 300°C, heating rate 10°C/min, frequency 10 Hz) satisfies: (1) tanδ at the maximum expansion temperature of the thermally expandable particles is 0.120 or less, and (2) The storage modulus G' at 170°C is 30,000 Pa or more.

The maximum expansion temperature of the heat-expandable particles is a value determined by the following measurement method. If the maximum expansion temperature of the thermally expandable particles is less than 170° C., the following problems may occur. •The heat-expandable particles expand (foam) during the long-time hot pressing step at high temperature (eg, 170°C), and the adhesiveness with the adherend decreases during the step. If the adhesion between the adherend and the adherend decreases, for example, in the cleaning step of the part, the cleaning liquid penetrates into the interface between the adherend and the adhesive. In addition, there is a possibility that the dimensions of the thermally expandable adhesive layer itself or the dimensions specified by the thermally expandable adhesive layer change, which may cause problems in the processing of parts. When the addition amount of the heat-expandable particles relative to 100 parts by mass of the adhesive component is less than 4 parts by mass, the force generated by the expansion of the heat-expandable particles is insufficient, and the surface of the adhesive layer is difficult to be uneven. At the time of thermal peeling, the effect of reducing the adhesion may not be sufficiently obtained. If the tanδ of the adhesive component at the maximum expansion temperature of the heat-expandable particles is higher than 0.120, that is, when the viscosity term in the adhesive component is significantly higher than the elastic term, the force generated by the maximum expansion of the heat-expandable particles is likely to become heat And escape. That is, it is difficult for the surface of the adhesive layer to become uneven by the force generated by the expansion of the thermally expandable particles. As a result, it is difficult to reduce the adhesive force with the adherend. If the storage modulus G' at 170°C of the adhesive component is less than 30,000 Pa, the heat-expandable particles may foam when pressed at high temperature for a long time. In addition, if the storage modulus G' of the adhesive component is less than 30,000 Pa, the cohesive force of the thermally expandable adhesive layer is also weak, so that when peeling off after use in a high temperature environment, it becomes easy to leave paste on the adherend.

[Adhesive ingredients] The adhesive components satisfy the requirements related to the predetermined parameters in the dynamic viscoelasticity measurement (temperature range -60°C to 300°C, heating rate 10°C/min, frequency 10 Hz). That is, tanδ at the maximum expansion temperature of the thermally expandable particles is 0.120 or less, preferably 0.001 or more and 0.120 or less, more preferably 0.001 or more and 0.110 or less, and particularly preferably 0.001 or more and 0.100 or less. Furthermore, the storage modulus G' at 170°C is 30,000 Pa or more, preferably 30,000 Pa or more and 1,000,000 Pa or less, more preferably 40,000 Pa or more and 1,000,000 Pa or less, particularly preferably 50,000 Pa or more and 1,000,000 Pa or less.

As the adhesive component, for example, acrylic adhesives, rubber-based adhesives, polysiloxane-based adhesives, polyester-based adhesives, polyamide-based adhesives, urethane-based adhesives, fluorine-based adhesives Among the agents, an adhesive with the above-mentioned properties is appropriately selected for use. The adhesive may be used alone or in combination of two or more.

In the present invention, as the adhesive, an acrylic adhesive, a rubber-based adhesive, and a polysiloxane-based adhesive can be preferably used in particular.

啉。 The type of the acrylic adhesive is not particularly limited, and various known acrylic adhesives containing an acrylic copolymer as a main component can be used. As the acrylic copolymer, for example, an acrylic copolymer obtained by copolymerizing a (meth)acrylate with a carboxyl group-containing monomer and other monomers optionally contained can be used. Specific examples of (meth)acrylates include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, (meth)acrylate n-butyl meth)acrylate, isobutyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, (meth)acrylate ) nonyl acrylate, isononyl (meth)acrylate, lauryl (meth)acrylate. Specific examples of the carboxyl group-containing monomer include (meth)acrylic acid, itaconic acid, crotonic acid, maleic acid (anhydride), fumaric acid, 2-carboxy-1-butene, 2- Carboxy-1-pentene, 2-carboxy-1-hexene, 2-carboxy-1-heptene. Specific examples of other monomers include hydroxyl-containing monomers such as 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate. ; Acrylonitrile; Styrene; 2-Methylolethyl acrylamide; Vinyl Acetate;

morpholino.

The acrylic copolymer is particularly preferably an acrylic polymer (A) having a hydroxyl group and a carboxyl group, which includes (meth)acrylic acid alkyl ester (A1) having an alkyl group having 4 to 12 carbon atoms, a carbon Alkyl (meth)acrylate (A2) of alkyl group with 1 to 3 atoms, carboxyl group-containing monomer (A3), hydroxyl group-containing monomer (A4) and other monomers (A5) as needed as a constituent. The components (A1), (A2), (A3), (A4), and (A5) may be used independently of each other, or two or more components may be used in combination.

As a specific example of the alkyl (meth)acrylate (A1) having an alkyl group having 4 to 12 carbon atoms, n-butyl (meth)acrylate, isobutyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate, lauryl (meth)acrylate. Further, as the alkyl (meth)acrylate monomer (A2) having an alkyl group having 1 to 3 carbon atoms, methyl (meth)acrylate, ethyl (meth)acrylate, (methyl)acrylate can be used. ) Alkyl (meth)acrylate having an alkyl group having 1 to 3 carbon atoms, such as propyl acrylate. In 100 mass % of the total constituents (monomer units) of the acrylic copolymer (A), the sum of the component amounts of the alkyl (meth)acrylates (A1) and (A2) is preferably selected from 50 mass % The above range is more preferably selected from the range of 60 mass % or more, and particularly preferably selected from the range of 70 mass % or more.

Specific examples of the carboxyl group-containing monomer (A3) include (meth)acrylic acid, itaconic acid, crotonic acid, maleic acid (anhydride), fumaric acid, and 2-carboxy-1-butene. , 2-carboxy-1-pentene, 2-carboxy-1-hexene, 2-carboxy-1-heptene. In 100 mass % of the total constituents (monomer units) of the acrylic copolymer (A), the compounding amount of the carboxyl group-containing monomer (A3) is preferably selected from the range of 0.5 to 15 mass %, more preferably From the range of 1-12 mass %, it is especially preferable to select from the range of 1-10 mass %.

Specific examples of the hydroxyl group-containing monomer (A4) include 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate. In 100 mass % of the total constituents (monomer units) of the acrylic copolymer (A), the compounding amount of the hydroxyl group-containing monomer (A4) is preferably selected from the range of 0.05 to 15 mass %, more preferably From the range of 0.07-12 mass %, it is especially preferable to select from the range of 0.1-10 mass %.

啉。於丙烯酸系共聚合體(A)之構成成分(單體單位)100質量%中，添加乙酸乙烯酯時其調配量較佳為選自0.1～10質量%之範圍。於丙烯酸系共聚合體(A)之總構成成分(單體單位)100質量%中，添加丙烯醯

啉時其調配量較佳為選自0.1～10質量%之範圍。 As the other monomer (A5), vinyl acetate, acrylamide are preferred

morpholino. In 100 mass % of structural components (monomer units) of the acrylic copolymer (A), when vinyl acetate is added, the compounding amount thereof is preferably selected from the range of 0.1 to 10 mass %. To 100 mass % of the total structural components (monomer units) of the acrylic copolymer (A), add acrylonitrile

In the case of linoline, the compounding amount is preferably selected from the range of 0.1 to 10% by mass.

The acrylic copolymer (A) may further contain monomers other than the monomers exemplified above as constituent components.

In the acrylic adhesive, a crosslinking agent having reactivity with the functional group of the acrylic copolymer is usually used. As the crosslinking agent, for example, isocyanate compounds, acid anhydrides, amine compounds, epoxy compounds, metal chelate compounds, aziridine compounds, and melamine compounds can be used. One type of these crosslinking agents may be used as needed, or two or more types may be used in combination. The blending amount of the crosslinking agent is usually selected from the range of 0.1 to 15 parts by mass, more preferably selected from the range of 0.3 to 12 parts by mass, and particularly preferably selected from the range of 0.5 to 10 parts by mass relative to 100 parts by mass of the acrylic copolymer range.

It is also possible to add at least one of the following components to the acrylic adhesive as needed: rosin, terpene, petroleum, lavender-indene, pure, phenolic, xylene and other adhesion imparting agent resins ; Mineral oils such as paraffin-based processing oils; polyester-based plasticizers; softeners including vegetable oils; aromatic secondary amines, monophenols, bisphenols, polyphenols, benzimidazoles, Antiaging agents such as phosphoric acid. Moreover, a saturated hydrocarbon resin can also be mix|blended with an acrylic adhesive.

The acrylic adhesive may further contain at least one of additives such as a silane coupling agent and an antioxidant as needed.

As the silane coupling agent, a silane coupling agent containing an glycidyl group is particularly preferable. Specific examples include: 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyl Methyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, gins (trimethoxysilylpropyl) isocyanurate, etc. One of these may be used, or two or more may be used in combination. The compounding amount of the silane coupling agent is preferably selected from the range of 0.01 to 0.5 parts by mass, more preferably selected from the range of 0.02 to 0.5 parts by mass, and particularly preferably selected from the range of 0.02 to 0.5 parts by mass relative to 100 parts by mass of the acrylic copolymer (A). The range of 0.03-0.3 mass part.

As an antioxidant, a hindered phenol type antioxidant is especially preferable. The blending amount of the antioxidant is preferably selected from the range of 0.01 to 1 part by mass, more preferably selected from the range of 0.02 to 0.7 part by mass, relative to 100 parts by mass of the acrylic copolymer (A).

In order to satisfy the above-mentioned parameters with the acrylic adhesive, for example, the theoretical Tg of the acrylic copolymer can be increased. Since the acrylic copolymer having a higher theoretical Tg generally has a higher cohesive force between polymers, the storage modulus G' in a high temperature environment tends to become higher. In addition, since G' is high in a high temperature environment, tanδ in a relatively high temperature environment is also low. Theoretical Tg can usually be calculated by the FOX formula, and the theoretical Tg is also increased by increasing the ratio of the (A2) component, (A3) component, (A4) component, and (A5) component in the entire acrylic copolymer. Moreover, increasing the weight average molecular weight (Mw) of an acrylic copolymer can also be mentioned as one method. If the weight-average molecular weight (Mw) is higher, the cohesive force of the polymers is generally higher and the fluidity is lower. Therefore, the storage modulus G' in a high-temperature environment is higher, and the tanδ in a high-temperature environment is lower. . Furthermore, the addition amount of the crosslinking agent for making acrylic copolymers couple|bond is also more preferable. When the addition amount of the crosslinking agent is large, the three-dimensional network structure formed by the crosslinking of the acrylic copolymers is more firmly formed, and as a result, G' becomes high and tanδ becomes low even in a high temperature environment.

The type of the rubber-based adhesive is not particularly limited, and various known rubber-based adhesives containing a rubber component as a main component can be used. Specific examples of the rubber component include butyl rubber, polyisobutylene rubber, isoprene rubber, styrene-isobutylene-styrene block copolymer, styrene-isoprene block copolymer, benzene Ethylene-butadiene rubber, styrene-isoprene-styrene block copolymer, styrene-butadiene-styrene block copolymer, styrene-ethylene-butylene-styrene block copolymer , styrene-ethylene-propylene-styrene block copolymer, styrene-ethylene-propylene block copolymer and other synthetic rubbers; natural rubber. One type of rubber component may be used, or two or more types of rubber components may be used in combination. The butyl rubber refers to a rubber generally containing a copolymer of isobutylene and 1 to 3 mass % of isoprene as a main component.

When a rubber-based adhesive is used for the adhesive layer, the adhesive composition constituting the adhesive layer preferably contains a rubber-based adhesive and a saturated hydrocarbon resin. Saturated hydrocarbon resins are hydrocarbon resins without unsaturated bonds, and are used to improve the adhesiveness of the adhesive layer.

The kind of the saturated hydrocarbon resin is not particularly limited, and for example, various alicyclic or aliphatic saturated hydrocarbon resins known as adhesion imparting agents can be used. One saturated hydrocarbon resin may be used, or two or more saturated hydrocarbon resins may be used in combination. In particular, an alicyclic saturated hydrocarbon resin is preferable, and a hydrocarbon resin from which an unsaturated bond has been removed by a hydrogenation treatment is more preferable. Commercially available saturated hydrocarbon resins include hydrogenated petroleum resins. Hydrogenated petroleum resins refer to resins obtained by hydrogenating petroleum resins (eg, aromatic petroleum resins, aliphatic petroleum resins, and copolymerized petroleum resins of alicyclic components and aromatic components). Among them, hydrogenated petroleum resins (alicyclic saturated hydrocarbon resins) obtained by hydrogenating aromatic petroleum resins are preferred. The hydrogenated petroleum resin can be obtained as a commercial product (for example, Arkon (trade name, Japanese registered trademark) P-100 manufactured by Arakawa Chemical Industry Co., Ltd.). The blending amount of the saturated hydrocarbon resin is preferably selected from the range of 0.01-100 parts by mass, more preferably selected from the range of 0.1-80 parts by mass, relative to 100 parts by mass of the adhesive component. The higher the content of saturated hydrocarbon resin, the higher the adhesion.

In order to satisfy the above-mentioned parameters with the rubber-based adhesive, for example, the molecular weight of the rubber component is increased to increase the cohesive force of the adhesive component. In addition, even if the rubber component is vulcanized by sulfur or resin, and the three-dimensional network structure formed by the cross-linking of the rubber components is more firmly formed, G' in a high temperature environment can be increased and tanδ can be reduced.

As a specific example of the polysiloxane-based adhesive used in the present invention, the following adhesives can be exemplified, which mainly contain: polysiloxane raw rubber (polydiethylene oxide having a structure containing D units [(CH ₃ ) ₂ SiO]) long-chain polymer of methylsiloxane); and MQ resin (polysiloxane having a three-dimensional structure _{comprising M units [(CH 3} ) ₃ SiO _1/2 ] and Q units [SiO _{4/2 ] structures} resin polymers). The adhesiveness of the adhesive containing this polysiloxane raw rubber and MQ resin is superior to that of the polysiloxane raw rubber monomer. In addition, by changing the ratio of polysiloxane raw rubber and MQ resin in the adhesive, the basic adhesive properties such as adhesive force, retention force, and tackiness can be controlled. Furthermore, the physical properties of the adhesive can be controlled by changing the ratio of the M unit and the Q unit of the MQ resin, or changing the molecular weight. Polysiloxane based adhesives are roughly classified into addition hardening types and peroxide hardening types according to their hardening mechanisms.

The addition-hardening polysiloxane-based adhesive includes, for example, a main agent containing an alkenyl group-containing polysiloxane raw rubber, MQ resin, and a cross-linking agent containing a SiH group-containing polyorganosiloxane. And it hardens|cures by carrying out a crosslinking reaction by heating under a platinum catalyst. The polysiloxane raw rubber containing an alkenyl group is typically a polyorganosiloxane having at least two alkenyl groups (eg, vinyl groups) bonded to silicon atoms in one molecule. The polyorganosiloxane containing SiH group is typically a polyorganosiloxane having at least two hydrogen atoms bonded to silicon atoms in one molecule.

The peroxide-curable polysiloxane-based adhesive includes, for example, a main agent containing a polysiloxane raw rubber that does not contain an alkenyl group, and an MQ resin. Furthermore, after adding a peroxide such as benzyl peroxide as a hardening agent, and removing the solvent, it hardens by heating at a high temperature.

Two or more types of polysiloxane-based adhesives can also be blended into the polysiloxane-based adhesive to improve various properties. However, the type or amount of the polysiloxane-based adhesive to be blended needs to be appropriately selected in a manner that does not impair the effect of the invention.

In order to satisfy the above-mentioned adhesive parameters with the polysiloxane-based adhesive, for example, it can be achieved by appropriately adjusting the ratio of polysiloxane rubber and polysiloxane resin. Specifically, the ratio (quality basis) of the polysiloxane rubber and the polysiloxane resin is preferably in the range of 30/70 to 90/10. If the ratio of the polysiloxane rubber is smaller than this range, the cohesion force in a high temperature environment tends to be weak, so that the storage modulus G' also becomes lower and tanδ becomes higher. On the contrary, if the ratio of polysiloxane rubber is large, it will be difficult to show sufficient initial adhesion force, and it will be difficult to stick to the adherend. Furthermore, if it is an addition-hardening polysiloxane-based adhesive, the bonding of the polysiloxane components can be controlled by adjusting the alkenyl content or the amount of the crosslinking agent in the polysiloxane raw rubber, and finally the storage can be controlled. Modulus G' or tanδ. If the content of alkenyl group or the amount of cross-linking agent in the polysiloxane raw rubber is increased, the sufficient storage modulus G' at high temperature tends to increase, and the tanδ tends to decrease. In the case of a peroxide-curable polysiloxane-based adhesive, the storage modulus G' or tanδ can be controlled by the amount of the added peroxide. When the additive amount of the peroxide is increased, the sufficient storage modulus G' at high temperature tends to be high, and the tan δ tends to be low.

Each of the adhesives described above may further contain at least one other component as needed. Specific examples include: solvents such as toluene; additives such as antioxidants, ultraviolet absorbers, light stabilizers, antistatic agents, flame retardants, electrical conductivity improvers, and thermal conductivity improvers; carbon black, calcium oxide, oxidized Fillers or pigments such as magnesium, silicon oxide, zinc oxide, titanium oxide, etc.

[thermally expandable particles] As the thermally expandable particles, those having a maximum expansion temperature of 170° C. or higher can be suitably used. The heat-expandable particles can be used alone or in combination of two or more. The heat-expandable particles can be appropriately selected from known heat-expandable microspheres, and are preferably microencapsulated heat-expandable particles. As such heat-expandable particles, for example, those obtained by encapsulating vaporizing agents such as liquid low-boiling hydrocarbons such as isobutane, propane, and pentane in a thermoplastic polymer shell may be mentioned. When such heat-expandable particles are heated, the polymer shell is softened, and the liquid low-boiling hydrocarbons contained therein are vaporized and expanded by the pressure. Examples of materials for forming the thermoplastic polymer shell include vinylidene chloride-acrylonitrile copolymers, polyvinyl alcohol, polyvinyl butyral, polymethyl methacrylate, polyacrylonitrile, polyvinylidene chloride Vinyl, Polycarbonate, etc.

As thermally expandable particles having a maximum expansion temperature of 170°C or higher, for example, Matsumoto Oil & Oil Pharmaceutical Co., Ltd.'s trade name "Matsumoto Microsphere" series (for example, trade name "Matsumoto Microsphere FN-180SSD", "Matsumoto Microsphere FN-180SSD" Matsumoto Microsphere FN-180SD", "Matsumoto Microsphere FN-180D", "Matsumoto Microsphere FN-190SSD", "Matsumoto Microsphere F-190D", "Matsumoto Microsphere F-260D") and other commercially available products.

In order to obtain the intended effect of the present invention, thermally expandable particles having a maximum expansion temperature of 170° C. or higher, particularly preferably 180° C. or higher and 320° C. or lower can be favorably used.

In the present invention, the maximum expansion temperature of the thermally expandable particles can be determined by using a thermal analyzer TMA (TMA7100, manufactured by Hitachi High-Tech Science Inc.). The maximum expansion temperature of heat-expandable particles is when the heat-expandable particles are placed in a 5 mmϕ aluminum pot, the inner lid is closed, and the heat-expandable particles are analyzed in compression mode (load: 0.05 N, heating rate: 10°C/min) The temperature at which the expansion of the particles reaches a maximum. For convenience of description, this temperature is set as TFmax. If heated to a temperature higher than the maximum expansion temperature, the gas inside the heat-expandable particle will penetrate the polymer shell, so it usually shrinks without breaking.

Furthermore, in order to efficiently and stably reduce the adhesive force of the heat-expandable adhesive layer by heat treatment, heat-expandable particles having a volume expansion ratio of 5 times or more can be favorably used.

With respect to 100 parts by mass of the resin component contained in the heat-expandable adhesive layer, the blending amount of the heat-expandable particles can be appropriately set to 4 parts by mass or more according to the desired initial adhesion or reduction of peeling force after foaming, etc. The range is preferably set to a range of 5 parts by mass or more, more preferably a range of 5 parts by mass or more and less than 100 parts by mass, and particularly preferably set to a range of 7 parts by mass or more and less than 80 parts by mass It is more preferable to set it suitably in the range of 10 mass parts or more and 50 mass parts.

For example, when the thermally expandable particles are exposed to a high temperature and high humidity environment such as a temperature of 65° C. and a relative humidity of 80%, the foamability may decrease. Therefore, the heat-peelable adhesive tape using heat-expandable particles should preferably be stored away from the environment of high temperature and high humidity. Furthermore, in order to maintain thermal peelability even in a state where the foamability has been lowered, the blending amount of the heat-expandable particles is preferably 7 parts by mass or more with respect to 100 parts by mass of the resin component contained in the heat-expandable adhesive layer.

The average particle diameter of the heat-expandable particles can be appropriately selected according to the thickness of the heat-expandable adhesive layer and the like. The average particle diameter of the heat-expandable particles having shapes such as microspheres can be preferably selected from, for example, a range of 100 μm or less, more preferably a range of 80 μm or less, and particularly preferably 1 μm or more and 50 μm or less. Scope. The heat-expandable particles having the target average particle diameter can be selected from commercially available products and used. Alternatively, the adjustment of the particle diameter of the heat-expandable particles may be performed during the production process of the heat-expandable particles, or the commercially available heat-expandable particles may be adjusted by a known method (eg, classification). In order to obtain the smoothness of the heat-expandable adhesive layer, the particle size of the heat-expandable particles is preferably kept the same.

The thickness of the heat-expandable adhesive layer is not particularly limited, for example, it is preferably selected from the range of 5 μm to 200 μm, more preferably selected from the range of 10 μm to 150 μm, particularly preferably selected from the range of 15 μm to 100 μm Scope.

In addition, as a method of foaming the heat-expandable particle in a heat-expandable adhesive layer, it can select and employ|adopt suitably from a well-known heat expansion method. Specifically, as the heat treatment for expanding the heat-expandable particles, for example, heating means such as a hot plate, a hot-air dryer, and an infrared heater can be suitably used. The heating temperature during the heat treatment may be equal to or higher than the foaming initiation temperature of the heat-expandable particles in the heat-expandable adhesive layer, and the conditions of the heat treatment can be appropriately set by the heating means, the material or heat capacity of the adherend.

[Layer composition of heat-peelable adhesive tape] As a layer structure of the heat-peelable adhesive tape of this invention, the layer structure which consists only of a thermally-expandable adhesive layer without other layers, or the layer which consists of a thermally-expandable adhesive layer and other layers can be mentioned. The heat-peelable adhesive tape composed of only a heat-expandable adhesive layer may be a heat-peelable adhesive tape composed of a single-layer heat-expandable adhesive layer, or a heat-peelable adhesive tape with several different heat-expandable adhesive layers . As another layer used as needed, a base material, a release liner, etc. are mentioned. As a form of the heat-peelable adhesive tape which has at least one of a base material and a release liner, the following forms are mentioned. (1) A heat-peelable adhesive tape with a heat-expandable adhesive layer on both sides of the substrate. (2) A heat-peelable adhesive tape with a heat-expandable adhesive layer only on one side of the base material. (3) A heat-peelable adhesive tape with a thermally expandable adhesive layer on one side of the substrate and a non-thermally expandable adhesive layer (an adhesive layer without thermal expansion) on the other side. (4) A heat-peelable adhesive tape having a heat-expandable adhesive layer on a release liner. (5) A thermally peelable adhesive tape having a thermally expandable adhesive layer and a non-thermally expandable adhesive layer on the release liner in this order. Furthermore, when the heat-expandable adhesive layer is formed on both surfaces of the base material, at least one of the heat-expandable adhesive layers may have the characteristics of the present invention described above. The thermally-expandable adhesive layer and the non-thermally-expandable adhesive layer different from the thermally-expandable adhesive layer of the present invention may be selected so as to obtain the target function or effect of the heat-peelable adhesive tape. Moreover, in the case of the form of said (1)-(3), you may provide a release liner on a thermally expandable adhesive layer or a non-thermally-expandable adhesive layer.

[other layers] [Substrate] The base material can be used as a member of a heat-peelable adhesive tape, for example, as a support for a heat-expandable adhesive layer or the like. The base material is not particularly limited, and known films, nonwoven fabrics, foams, cloths, papers, and combinations thereof can be used. It is preferably a film-like base material that can easily obtain uniformity of thickness in the production steps of thin substrates and the like. In particular, it is preferable that it is a resin film which has the heat resistance required in a use environment. Specific examples thereof include polyimide (PI), polyether ether ketone (PEEK), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and the like. Ester; polyphenylene sulfide (PPS), polyamide imide (PAI), polyether sulfide (PES), polytetrafluoroethylene (PTFE) and other resin films. These films can be used as a single layer or as a laminated film of two or more layers. The laminated film may include a combination of one or more layers composed of different materials. As the heat-resistant resin film, a polyimide film excellent in dimensional stability at high temperature is particularly preferred. The thickness of the substrate is not particularly limited, but is preferably selected from the range of 1 μm or more and 200 μm or less, more preferably selected from the range of 2 μm or more and 150 μm or less, and particularly preferably selected from the range of 2 μm or more and 125 μm the following range.

The surface of the substrate on which the adhesive layer is arranged can also be subjected to an easy-bonding treatment as required. As an adhesion-facilitating treatment, for example, a primer treatment, a corona treatment, an etching treatment, a plasma treatment, a sand blast treatment, etc. are mentioned. One can be selected from among them, or a combination of two or more can be selected.

Surface treatments such as antistatic can also be applied to the substrate as needed. As the antistatic treatment, treatment with an antistatic agent such as a cationic surfactant, an anionic surfactant, and a nonionic surfactant can be exemplified. Moreover, as needed, a coloring process may be performed to a base material by printing, kneading, or the like.

[Non-thermally expandable adhesive layer] It does not specifically limit as an adhesive for forming a non-heat-expandable adhesive layer, The adhesive previously exemplified in the description of a heat-expandable adhesive layer can be used similarly. As the adhesive, for example, known adhesives such as acrylic adhesives, rubber-based adhesives, polysiloxane-based adhesives, polyester-based adhesives, polyamide-based adhesives, and urethane-based adhesives can be used. agent. These adhesives may be used alone or in combination of two or more. In the non-thermally expandable adhesive layer, at least one of additives such as adhesion imparting agents, coloring pigments, antiaging agents, antioxidants, antistatic agents, crosslinking agents, and silane coupling agents may also be formulated.

The thickness of the non-thermally expandable adhesive layer is, for example, preferably selected from the range of 200 μm or less, more preferably selected from the range of 1 μm or more and 150 μm or less, and particularly preferably selected from the range of 1 μm or more and 100 μm or less. Furthermore, as a method for forming the non-heat-expandable adhesive layer, the same method as the above-mentioned thermally-expandable adhesive layer can be used (for example, a method of coating on a substrate, coating on a release liner to form an adhesive layer and then transferring the adhesive layer). method of printing onto a substrate, etc.).

[release liner] As a release liner, a well-known release paper etc. can be used. The release liner is used as a protective material for the heat-expandable adhesive layer, and is peeled off when the heat-peelable adhesive sheet is attached to the adherend. As a release liner, for example, it can also be used: a plastic film (for example, a PET film) or a substrate with a release layer such as paper that has been surface-treated with release agents such as polysiloxane-based, long-chain alkyl-based, and fluorine-based release agents; Low-adhesion substrates containing non-polar polymers such as fluorine-based resins (such as polytetrafluoroethylene) or olefin-based resins (such as polyethylene, polypropylene, etc.).

An embodiment of the heat-peelable adhesive tape having a base material and a release liner as other layers will be described with reference to FIG. 1 . FIG. 1 is a schematic cross-sectional view in the thickness direction showing an embodiment of the heat-peelable adhesive tape of the present invention. The heat-peelable adhesive sheet 1 shown in FIG. 1 has a base material 2, a heat-expandable adhesive layer 3 and a release liner 4. The two layers of the heat-expandable adhesive layer 3 may be the same or different. The two layers of release liners 4 may be the same release liners or different release liners.

The heat-peelable pressure-sensitive adhesive sheet 1 shown in FIG. 1 has the form of a double-sided pressure-sensitive adhesive tape including two heat-expandable pressure-sensitive adhesive layers 3 formed on both sides of the base material 2, respectively. In the form of the double-sided adhesive tape, at least one of the two adhesive layers may be the thermally expandable adhesive layer of the present invention. For example, regarding the form of the double-sided adhesive tape, at least one of the two adhesive layers 3 may be the thermally expandable adhesive layer of the present invention, and the other layer may be a thermally expandable adhesive layer other than the thermally expandable adhesive layer of the present invention or not have thermal expansion. Adhesive layer (non-thermal expansion adhesive layer).

[Manufacturing method of heat-peelable adhesive tape] A heat-peelable adhesive tape comprising a heat-expandable adhesive layer can be produced by the following method: coating a layer-forming composition material comprising a resin component and heat-expandable particles on a substrate for forming a heat-expandable adhesive layer, and heating The heat-expandable adhesive layer formed by the cross-linking reaction of the coating layer is peeled off from the base material for forming the heat-expandable adhesive layer. A heat-peelable adhesive tape having a heat-expandable adhesive layer on a base material or a release liner serving as a constituent member of the heat-peelable adhesive tape can be produced, for example, by forming a layer containing a resin component and heat-expandable particles with The composition material is coated on the substrate or the release liner, and the coating layer is subjected to a crosslinking reaction by heating to form a thermally expandable adhesive layer. In addition, the layer-forming composition material containing the resin component and the heat-expandable particles may be coated on a release liner (for example, a PET film treated with polysiloxane), and the coated layer may be subjected to a cross-linking reaction by heating , and then transfer to one or both sides of the base material to form a heat-peelable adhesive tape. It is important that the heating temperature for crosslinking is sufficiently lower than the foaming initiation temperature of the heat-expandable particles. For the formation of the coating layer, known coating apparatuses such as a roll coater, a die coater, and a die lip coater can be used, for example. When heating is performed after coating, the solvent in the layer-forming material can also be removed at the same time as the crosslinking reaction is performed by heating. In the case of forming the heat-expandable adhesive layer by transfer printing, in order to improve the adhesion between the substrate and the heat-expandable adhesive layer, thereby obtaining the smoothness of the surface, lamination is preferably performed by a heated roller or the like.

The heat-peelable pressure-sensitive adhesive tape of the present invention can be favorably used for the heat-pressing treatment of the adherend to which the heat-peelable pressure-sensitive adhesive tape is temporarily fixed. One form of the method of using the heat-peelable adhesive tape of the present invention in the hot-pressing treatment of the adherend includes: the step of temporarily fixing the above-mentioned adhesive tape to the adherend; The step of heat-pressing the body; The step of heating the adhesive tape temporarily fixed to the above-mentioned hot-pressed adherend to the temperature for peeling; and the above-mentioned heating to the temperature for peeling The adhesive tape from the adherend Stripping step. One form of the hot-pressing method of the adherend using the method of use is the hot-pressing method of the adherend having the temporarily fixed heat-peelable adhesive tape, comprising: temporarily fixing the heat-peelable adhesive tape of the above-mentioned constitution Steps on the adherend; Steps of heat-pressing the above-mentioned adherends temporarily fixed with the adhesive tape; ; and the step of peeling the above-mentioned adhesive tape heated to a temperature for peeling from the above-mentioned adherend. The form of temporarily fixing the heat-peelable adhesive tape to the adherend includes: temporary fixing of the adherends to each other, temporary fixing when the adherend is transported, reinforcement, protection or shielding of the adherend, and Resin sealing, etc. Moreover, as a hot pressing process, the hot pressing process in the manufacturing process of an electronic component and a semiconductor component is mentioned. As conditions that can make good use of the hot-pressing step of the heat-peelable adhesive tape of the present invention, a temperature of 120 to 240° C., a time of 5 minutes to 10 hours, and a pressure of 5 to 40 kgf/cm ² may, for example, be mentioned. [Example]

Hereinafter, the present invention will be described in further detail by taking Examples and Comparative Examples as examples, but the present invention is not limited to these Examples at all. In the description below, "parts" means parts by mass.

<Preparation example of acrylic copolymer> The polymerization of the acrylic copolymer having the composition shown in Table 1 was carried out. The compounding ratio of each component in Table 1 shows the ratio when the total of components A1-A5 is made into 100 parts. The theoretical Tg and weight average molecular weight (Mw) of each acrylic copolymer are collectively described in Table 1 for reference. The theoretical Tg is a value calculated by the FOX formula, and can be adjusted by appropriately selecting the composition of the acrylic monomer. In addition, this weight average molecular weight (Mw) is the value obtained by measuring the molecular weight of the standard polystyrene conversion of an acrylic copolymer by GPC method using the following measuring apparatus and conditions. • Device: LC-2000 series (manufactured by Nippon Shoko Co., Ltd.) • Column: ShodexKF-806M×2, ShodexKF-802×1 • Eluent: Tetrahydrofuran (THF) • Flow rate: 10 mL/min • Column temperature: 40℃ • Injection volume: 100 μL • Detector: Refractometer (RI) • Measurement sample: Dissolved an acrylic polymer in THF to prepare a solution with a concentration of 0.5 mass % of the acrylic polymer, and remove the contaminants by filtration with a filter. When the weight average molecular weight (Mw) is used in the polymerization of the acrylic copolymer, the type and amount of the polymerization initiator can be appropriately selected (for example, relative to 100 parts by mass of the acrylic monomer, 0.1 part by mass of lauryl peroxide can be selected ), the type and amount of the chain transfer agent (for example, 0.1 part by mass of n-dodecanethiol is selected with respect to 100 parts by mass of the acrylic monomer), the polymerization initiation concentration (for example, 50% by mass), etc. are adjusted.

[Table 1] Table 1 Preparation example of component A acrylic copolymer No. A1 A2 A3 A4 A5 Theoretical Tg Mw 1 2-EHA: 70 BA: 14.9 MA: 5 AA: 10 4-HBA: 0.1 - -66.9 1.29 million 2 2-EHA: 70 BA: 5 MA: 10 AA: 10 2-HEA: 5 - -63.2 1.01 million 3 2-EHA: 10 MA: 20 EA: 50 AA: 10 4-HBA: 6 2-HEA: 4 - -17.9 670,000 4 2-EHA: 87.9 MA: 3 AA: 7 2-HEA: 0.1 VAc: 2 -74.5 1.11 million 5 2-EHA: 86 MA: 3 AA: 7 2-HEA: 2 VAc: 2 -73.4 440,000 6 2-EHA: 90 - AA: 3 4-HBA: 0.1 VAc: 5 ACMO: 1.9 -76.2 750,000

啉 Abbreviations in Table 1 refer to the following compounds. "2-EHA": 2-ethylhexyl acrylate "BA": n-butyl acrylate "MA": methyl acrylate "EA": ethyl acrylate "AA": acrylic acid "4-HBA": acrylic acid-4 -Hydroxybutyl ester "2-HEA": 2-hydroxyethyl acrylate "VAc": Vinyl acetate "ACMO": Acrylonitrile

morpholino

<Examples 1 to 12 and Comparative Examples 1 to 8: Production of heat-peelable acrylic pressure-sensitive adhesive tapes> As shown in Table 2, with respect to 100 parts of solid content of the acrylic copolymer (ingredient A) obtained in Table 1, the crosslinking agent (ingredient B) and the antioxidant (ingredient C) were mixed at a predetermined mixing ratio (mass basis). ), a silane coupling agent (component D), and toluene (diluent solvent) to obtain an adhesive composition. Furthermore, with respect to 100 parts of adhesive components, a foaming agent (component F) was mixed at the mixing ratio (mass basis) shown in Table 2 to prepare a thermally expandable adhesive composition.

[Table 2] Table 2 Preparation example of heat-expandable adhesive composition (acrylic type) Adhesive composition (acrylic, solid content ratio) foaming agent Ingredient A Ingredient B Ingredient C Ingredient D Ingredient F Example 1 No.1: 100 B1: 0.50 C1: 0.67 D1: 0.03 F1: 30 Example 2 No.1: 100 B1: 0.50 C1: 0.67 D1: 0.03 F1: 5 Example 3 No.1: 100 B1: 0.50 C1: 0.67 D1: 0.03 F1: 10 Example 4 No.1: 100 B1: 0.50 C1: 0.67 D1: 0.03 F1: 50 Example 5 No.1: 100 B1: 1.67 C1: 0.67 D1: 0.03 F1: 30 Example 6 No.2: 100 B1: 0.50 C1: 0.67 D1: 0.03 F1: 30 Example 7 No.3: 100 B1: 0.50 C1: 0.67 D1: 0.03 F1: 30 Example 8 No.4: 100 B1: 0.50 C1: 0.67 D1: 0.03 F1: 30 Example 9 No.4: 100 B1: 1.67 C1: 0.67 D1: 0.03 F1: 30 Example 10 No.5: 100 B1: 1.67 C1: 0.67 D1: 0.03 F1: 30 Example 11 No.6: 100 B1: 0.50 C1: 0.67 D1: 0.03 F1: 30 Example 12 No.6: 100 B1: 1.67 C1: 0.67 D1: 0.03 F1: 30 Comparative Example 1 No.1: 100 B1: 0.50 C1: 0.67 D1: 0.03 none Comparative Example 2 No.1: 100 B1: 0.50 C1: 0.67 D1: 0.03 F1: 3 Comparative Example 3 No.1: 100 B1: 0.50 C1: 0.67 D1: 0.03 F2: 30 Comparative Example 4 No.1: 100 B1: 0.08 C1: 0.67 D1: 0.03 F1: 30 Comparative Example 5 No.1: 100 B1: 0.17 C1: 0.67 D1: 0.03 F1: 30 Comparative Example 6 No.1: 100 B2: 4.50 C1: 0.67 D1: 0.03 F1: 30 Comparative Example 7 No.5: 100 B1: 0.50 C1: 0.67 D1: 0.03 F1: 30 Comparative Example 8 No.5: 100 B1: 0.20 C1: 0.67 D1: 0.03 F1: 30

The heat-expandable adhesive composition was coated on a PET film with a thickness of 50 μm treated with polysiloxane release. Next, the diluent solvent is removed at 90 to 100° C., dried, and subjected to a crosslinking reaction to form a thermally expandable adhesive layer. The heat-expandable adhesive layer was attached and transferred to both sides of a polyimide film with a thickness of 12 μm. Furthermore, using a desktop laminator, lamination was performed at a temperature of 100°C. Then, it aged at 40 degreeC for 3 days, and obtained the double-sided heat-peelable adhesive tape. The heat-expandable adhesive composition was applied so that the thickness of the adhesive layer on one side after lamination was 50 μm. The thickness of the obtained double-sided adhesive tape was 112 μm.

Abbreviations in Table 2 indicate the following ingredients. "B1": epoxy-based crosslinking agent (manufactured by Soken Chemical Co., Ltd., trade name E-5XM, solid content concentration 5%) "B2": Isocyanate-based crosslinking agent (manufactured by Tosoh Corporation, trade name Coronate L-45E, solid content concentration 45%) "C1": Antioxidant (manufactured by BASF, trade name Irganox 1010) "D1": Silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., trade name KBM-403, solid content concentration 10%) "F1": Thermally expandable microcapsules (Matsumoto Microsphere FN-180SSD, manufactured by Matsumoto Oil Pharmaceutical Co., Ltd., maximum expansion temperature 192°C) "F2": heat-expandable microcapsules (Matsumoto Microsphere FN-100SSD, trade name Matsumoto Microsphere, maximum expansion temperature 162°C)

<Example 13: Production of heat-peelable polysiloxane-based adhesive tape> First, two kinds of trial products (I, II) of the addition-curable polysiloxane-based adhesive stock solution were prepared. These trial products were obtained by appropriately changing the compounding ratio of MQ resin to polysiloxane raw rubber, the type of MQ resin, the olefinic group content of polysiloxane raw rubber, and the amount of cross-linking, and after curing, measured by the following methods A trial product of an adhesive that is adjusted in such a way that the storage modulus G' and tanδ show various values. In Example 13, among these trial products, an addition-hardening polysiloxane adhesive with a storage modulus G' at 170°C of 125,770 Pa and a tanδ of 0.053 at the maximum expansion temperature of the thermally expandable particles F1 was selected. Agent stock solution (I). 100 parts of addition-hardening polysiloxane-based adhesive stock solution (I) with a solid content concentration of 50% by mass, 25 parts of toluene as a dilution solvent, and a platinum catalyst as a hardening catalyst (manufactured by Shin-Etsu Chemical Co., Ltd.) were prepared. , CAT-PL-50T) 1.25 parts of polysiloxane adhesive composition. Furthermore, 15 parts of heat-expandable microcapsules F1 (manufactured by Matsumoto Oil Pharmaceutical Co., Ltd., trade name Matsumoto Microsphere FN-180SSD, maximum expansion temperature 192° C.) as a foaming agent were mixed to prepare a heat-expandable adhesive composition.

The heat-expandable adhesive composition was coated on one side of a primer-treated polyimide (PI) film with a thickness of 50 μm in such a way that the thickness of the adhesive layer after drying was 50 μm, and placed in a drying oven. After drying at 120° C. for 2 minutes, the solvent was removed, and heat-hardening was performed to form a heat-expandable adhesive layer. Then, as a release liner, a polyethylene terephthalate (PET) film with a thickness of 50 μm, which has undergone a release treatment with a fluorine-substituted alkyl modified polysiloxane resin, was attached to the adhesive layer to obtain a thermal Peelable single-sided adhesive tape.

<Comparative example 9: Production of heat-peelable polysiloxane-based adhesive tape> In Comparative Example 9, the stock solution (II) of the addition-hardening polysiloxane-based adhesive was selected with storage modulus G' at 170°C of 39,749 Pa and tanδ at the maximum expansion temperature of thermally expandable particles F1 of 0.532. The following polysiloxane-based adhesive composition was prepared, which included 100 parts of addition-hardening polysiloxane-based adhesive stock solution (II) with a solid concentration of 50% by mass, 25 parts of toluene as a diluting solvent, and 25 parts of toluene as a hardening catalyst. Platinum catalyst (manufactured by Shin-Etsu Chemical Co., Ltd., CAT-PL-50T) 1.25 parts. Furthermore, 15 parts of heat-expandable microcapsules F1 (manufactured by Matsumoto Oil Pharmaceutical Co., Ltd., trade name Matsumoto Microsphere FN-180SSD, maximum expansion temperature 192° C.) as a foaming agent were mixed to prepare a heat-expandable adhesive composition. Except for this, a heat-peelable single-sided adhesive tape was obtained by the same method as in Example 13.

The heat-peelable adhesive tapes obtained in Examples 1 to 13 and Comparative Examples 1 to 9 were evaluated by the following method. The results are shown in Tables 3-1 to 3-4.

(a) [Measurement of dynamic viscoelasticity of adhesive composition] Regarding the acrylic adhesive composition, according to the preparation composition shown in Table 2, which does not contain thermally expandable microcapsules (F), crosslinking was added to 100 parts of solid content of the acrylic copolymer (A) obtained in Table 1. Agent (B), antioxidant (C), and silane coupling agent (D) were mixed to prepare an adhesive composition for sample preparation for measurement. With regard to the polysiloxane-based adhesive composition, except that the heat-expandable microcapsules (F) were not included, by the same method as in Example 13 and Comparative Example 9, an adhesive composition for sample preparation for measurement was prepared.

Each adhesive composition used as a measurement sample was independently used, and in the case of an acrylic adhesive composition, the thickness after drying was applied to a thickness of 50 μm after polysiloxane release treatment. on 50 μm PET film. Next, the solvent is removed at 90 to 100° C., dried, and subjected to a crosslinking reaction to form an adhesive layer. This adhesive layer was laminated to form a laminated body with a thickness of 2 mm, which was further aged at 40° C. for 3 days, and used as a measurement sample. In the case of a polysiloxane-based adhesive composition, it was coated on a 50 μm thick poly on ethylene terephthalate (PET) film. Then, it dried at 120 degreeC for 2 minutes in a drying furnace, and removed the solvent, and it heated and hardened, and formed the adhesive bond layer. This adhesive layer was laminated to form a laminated body having a thickness of 2 mm, and this was used as a measurement sample.

The sample for measurement was sandwiched between parallel discs (ϕ8 mm), and a dynamic viscoelasticity measuring device (manufactured by Rheometric Scientific, device name RDAIII) was used, while applying shear strain at a frequency of 10 Hz, while applying a shear strain of 10 °C/min. The heating rate was measured, and the storage modulus (G') and the loss elastic modulus (G'') in the range of -50°C to 300°C were measured. From the storage modulus (G') and the loss elastic modulus (G''), the loss tangent tanδ was calculated by the following formula. tanδ = loss elastic modulus (G'')/storage modulus (G') Table 3-1 shows the storage modulus (G') at 23°C and 170°C, and the measured values of tanδ at the maximum expansion temperature TFmax°C.

(b) Determination of TFmax The maximum expansion temperature (TFmax) of the heat-expandable particles is measured by the above-mentioned method.

[Evaluation of acrylic double-sided heat-peelable adhesive tape] (c) [Initial peeling force of copper foil, initial peeling force of heat-peelable adhesive tape with respect to copper plate] The samples (double-sided adhesive tapes) described in Examples 1 to 12 and Comparative Examples 1 to 8 cut to a width of 10 mm and a length of 90 mm were placed on a copper plate ( A transfer plate is assumed) and the glossy surface of a copper foil with a thickness of 35 μm, a width of 10 mm, and a length of 90 mm (assumed to be a substrate product, electrolytic copper foil manufactured by Futian Metal Co., Ltd.), etc., are bonded together. At a speed of 300 mm/min, a roller with a weight of 2 kg covered with a rubber layer was pressed back and forth once to carry out pressing, and then it was left at 23° C. for 20 to 40 minutes. Then, using a tensile tester, the force required to peel off the copper foil from the above-mentioned tape was measured at a speed of 300 mm/min and an angle of 90° in an environment of 23°C. Next, the force required to peel the above-mentioned tape from the copper plate at a speed of 300 mm/min and an angle of 90° was measured using a tensile tester.

(d) [Peeling force of copper foil when heat-peeling treatment, peeling force of heat-peelable adhesive tape with respect to copper plate] The samples (double-sided adhesive tapes) described in Examples 1 to 12 and Comparative Examples 1 to 8 cut to a width of 10 mm and a length of 90 mm were placed on a copper plate ( Between the 35 μm thick, 10 mm wide, and 90 mm long copper foil (presumed to be a substrate product) and the like are bonded together. The roller covered with a rubber layer weighing 2 kg was pressed back and forth once at a speed of 300 mm/min, and then heated by a dryer at 200° C. for 3 minutes. Place to cool at 23°C for more than 1 hour, then use a tensile tester to measure the force required to peel the copper foil from the above tape at a speed of 300 mm/min and an angle of 90°, and visually confirm whether there is any paste on the adherend agent residues. Next, the force required to peel the above-mentioned tape from the copper plate at a speed of 300 mm/min and an angle of 90° was measured using a tensile tester, and the presence or absence of paste residue on the adherend was visually confirmed.

The peeling force and the paste residual property when the heat peeling treatment was performed were determined according to the following criteria. (Peeling force of copper foil during heat peeling treatment) A: Natural peeling during heating, or peeling force is less than 20% of the initial peeling force (good). B: The peeling force is 20% or more of the initial peeling force (defective). (Paste Residual Properties of Copper Foil at the Time of Heat Peeling Treatment) A: No paste remains (good). B: There is a paste residue (defective). (Peeling force of heat-peelable adhesive tape with respect to copper plate during heat-peeling treatment) A: Natural peeling during heating, or peeling force is less than 20% of the initial peeling force (good). B: The peeling force is 20% or more of the initial peeling force (defective). (Paste Residual Properties of Copper Plates During Heat Stripping Treatment) A: No paste remains (good). B: There is a paste residue (defective).

(e) [Suppression of foaming during high temperature and long-term pressurization] Examples 1 to 12 and Comparative Examples 2, 3, 7, and 8 whose evaluations of (d) were good (all evaluations were A) were evaluated as follows Foaming suppression when pressurized for a long time at high temperature. The samples (double-sided adhesive tapes) of Examples 1 to 12 and Comparative Examples 2, 3, 7, and 8 cut to a width of 10 mm and a length of 90 mm were arranged on a thickness of 0.7 mm, a width of 25 mm, and a length of 125 mm. A copper plate with a thickness of mm (assuming a conveying plate) and a copper foil with a thickness of 35 μm, a width of 10 mm, and a length of 90 mm (assuming a substrate product) are bonded together. At a speed of 300 mm/min, a roller with a weight of 2 kg covered with a rubber layer was pressed back and forth once, and then a heating press was used to apply a pressure of 26 kg/ cm ² was pressurized for 1 hour. At this time, in order to apply pressure uniformly, a polysilicon rubber sheet (IS-825, hardness 50°, manufactured by IRUMAGAWA RUBBER CO., LTD.) with a thickness of 1 mm, a width of 25 mm, and a length of 125 mm was laid under the copper plate. , the polysiloxane rubber sheet cut into a width of 10 mm and a length of 90 mm is placed on the test piece, and pressed between them. After standing to cool at 23° C. for 1 hour or more, the tape was peeled off from the copper foil and the copper plate, the presence or absence of foaming was visually confirmed, and the obtained results were evaluated according to the following criteria. A: The heat-expandable adhesive layer was not foamed during hot pressing (good). B: The heat-expandable adhesive layer was foamed during hot pressing (defective).

(f) [Peeling force of copper foil and peeling force of heat-peelable adhesive tape with respect to copper plate when heat-peeling treatment is performed after high temperature and long-term pressure] (Evaluation A) Examples and In the comparative example, the peeling force of the copper foil and the peeling force of the heat-peelable adhesive tape with respect to the copper plate were evaluated by the following methods when the heat-peeling treatment was performed after being pressed at a high temperature for a long time. The samples (double-sided adhesive tapes) of Examples 1 to 12 and Comparative Example 2 cut to a width of 10 mm and a length of 90 mm were placed on a copper plate with a thickness of 0.7 mm, a width of 25 mm, and a length of 125 mm (assuming A transfer plate) and a copper foil (presumed to be a substrate product) with a thickness of 35 μm, a width of 10 mm, and a length of 90 mm are bonded together. At a speed of 300 mm/min, a roller with a weight of 2 kg covered with a rubber layer was pressed back and forth once, and then a heating press was used to apply a pressure of 26 kg/ cm ² was pressurized for 1 hour. At this time, in order to apply pressure uniformly, a polysilicon rubber sheet (IS-825, hardness 50°, manufactured by IRUMAGAWA RUBBER CO., LTD.) with a thickness of 1 mm, a width of 50 mm, and a length of 125 mm was laid under the copper plate. , the polysiloxane rubber sheet cut into a width of 10 mm and a length of 90 mm was placed on the test piece, and pressed between them. It stood to cool at 23 degreeC for 1 hour or more, and after that, it heated for 3 minutes with the dryer of 200 degreeC. Place to cool at 23°C for more than 1 hour, then use a tensile tester to measure the force required to peel the copper foil from the above tape at a speed of 300 mm/min and an angle of 90°, and visually confirm whether there is any paste on the adherend agent residues. Next, using a tensile tester, the force required to peel the tape off the copper plate at a speed of 300 mm/min and an angle of 90° was measured, and the presence or absence of paste residue on the adherend was visually confirmed.

The peeling of the copper foil and the peeling of the tape with respect to the copper plate were evaluated according to the following criteria. (Peeling force of copper foil during heat peeling treatment) A: Natural peeling during heating, or peeling force is less than 20% of the initial peeling force (good). B: The peeling force is 20% or more of the initial peeling force (defective). (Paste Residual Properties of Copper Foil at the Time of Heat Peeling Treatment) A: No paste remains (good). B: There is a paste residue (defective). (Peeling force of heat-peelable adhesive tape with respect to copper plate during heat-peeling treatment) A: Natural peeling during heating, or peeling force is less than 20% of the initial peeling force (good). B: The peeling force is 20% or more of the initial peeling force (defective). (Paste Residual Properties of Copper Plates During Heat Stripping Treatment) A: No paste remains (good). B: There is a paste residue (defective).

[Evaluation of polysiloxane-based heat-peelable single-sided adhesive tapes] (g) [Initial peeling force of copper foil] The samples described in Example 13 and Comparative Example 9 cut to a width of 10 mm and a length of 90 mm (it is assumed to be a single-sided adhesive tape for reinforcement during transport) were attached to a thickness of 35 μm, a width of 10 mm, and a length of 90 mm. The glossy surface of the copper foil of mm (assumed to be a substrate product, electrolytic copper foil manufactured by Futian Metal Co., Ltd.). At a speed of 300 mm/min, a roller with a weight of 2 kg covered with a rubber layer was pressed back and forth once to carry out pressing, and then it was left at 23° C. for 20 to 40 minutes. After that, using a tensile tester, the force required to peel off the copper foil from the tape was measured at a speed of 300 mm/min and an angle of 90° in an environment of 23°C. At this time, the base material side of the single-sided pressure-sensitive adhesive tape was fixed to a SUS plate with a paper double-sided pressure-sensitive adhesive tape (No. 778 manufactured by Teraoka Seisakusho Co., Ltd.), and the measurement was performed.

(h) [Peeling force of copper foil during heat peeling treatment] The samples described in Example 13 and Comparative Example 9 cut to a width of 10 mm and a length of 90 mm (it is assumed to be a single-sided adhesive tape for reinforcement during transportation) were attached to a thickness of 35 mm, a width of 10 mm, and a length of 90 mm. The glossy surface of the copper foil of mm (assumed to be a substrate product, electrolytic copper foil manufactured by Futian Metal Co., Ltd.). The roller covered with a rubber layer weighing 2 kg was pressed back and forth once at a speed of 300 mm/min, and then heated by a dryer at 200° C. for 3 minutes. Place and cool at 23°C for more than 1 hour, then use a tensile tester to measure the force required to peel off the copper foil from the tape at a speed of 300 mm/min and an angle of 90°, and visually confirm whether there is paste on the adherend residue. At this time, the base material side of the single-sided pressure-sensitive adhesive tape was fixed to a SUS plate with a paper double-sided pressure-sensitive adhesive tape (No. 778 manufactured by Teraoka Seisakusho Co., Ltd.), and the measurement was performed.

The peeling force and paste residual property at the time of heat peeling treatment were judged according to the following criteria. (Peeling force of copper foil during heat peeling treatment) A: Natural peeling during heating, or peeling force is less than 20% of the initial peeling force (good). B: The peeling force is 20% or more of the initial peeling force (defective). (Paste Residual Properties of Copper Foil at the Time of Heat Peeling Treatment) A: No paste remains (good). B: There is a paste residue (defective).

(i) [Foaming inhibition during high temperature and long-term pressurization] For the examples that were evaluated as good in the above (h) (all evaluations were A), the foaming inhibition during high-temperature and long-term pressurization was evaluated as follows. The sample described in Example 13 cut to a width of 10 mm and a length of 90 mm (it is assumed to be a single-sided adhesive tape for reinforcement during transportation) is attached to a copper foil of thickness 35 μm, width 10 mm, and length 90 mm The glossy surface (assumed to be a substrate product, electrolytic copper foil made by Futian Metal Co., Ltd.). At a speed of 300 mm/min, a roller with a weight of 2 kg covered with a rubber layer was pressed back and forth once, and then a heating press was used to apply a pressure of 26 kg/ cm ² was pressurized for 1 hour. At this time, in order to apply pressure evenly, a polysilicon rubber sheet (IS-825, hardness 50 mm) was laid under the copper plate with a thickness of 0.7 mm, a width of 25 mm and a length of 125 mm. °, manufactured by IRUMAGAWA RUBBER CO., LTD.), the polysiloxane rubber sheet cut into a width of 10 mm and a length of 90 mm was placed on the test piece, and pressed therebetween. After standing to cool at 23° C. for 1 hour or more, the tape was peeled off from the copper foil, the presence or absence of foaming was visually confirmed, and the obtained results were evaluated according to the following criteria. A: The heat-expandable adhesive layer was not foamed during hot pressing (good). B: The heat-expandable adhesive layer was foamed during hot pressing (defective).

(j) [Peeling force of copper foil when heat-peeling treatment is performed after high-temperature and long-time pressing] For the examples that were evaluated as good (A evaluation) in the above (h), the following methods were used to evaluate the high-temperature and long-time pressing followed by heating The peeling force of copper foil during peeling treatment. The sample described in Example 13 cut to a width of 10 mm and a length of 90 mm (it is assumed to be a single-sided adhesive tape for reinforcement during transportation) is attached to a copper foil of thickness 35 μm, width 10 mm, and length 90 mm The glossy surface (assumed to be a substrate product, electrolytic copper foil made by Futian Metal Co., Ltd.). After reciprocating a roller covered with a rubber layer with a weight of 2 kg at a speed of 300 mm/min, the pressure applied to the entire test piece was 26 kg/m using a heating press at a temperature of 170°C. cm ² was pressurized for 1 hour. At this time, in order to apply pressure evenly, a polysilicon rubber sheet (IS-825, hardness 50 mm) was laid under the copper plate with a thickness of 0.7 mm, a width of 25 mm and a length of 125 mm. °, manufactured by IRUMAGAWA RUBBER CO., LTD.), the polysiloxane rubber sheet cut into a width of 10 mm and a length of 90 mm was placed on the test piece, and pressed therebetween. It stood to cool at 23 degreeC for 1 hour or more, and after that, it heated for 3 minutes with the dryer of 200 degreeC. Place to cool at 23°C for more than 1 hour, then use a tensile tester to measure the force required to peel the copper foil from the above tape at a speed of 300 mm/min and an angle of 90°, and visually confirm whether there is any paste on the adherend agent residues. At this time, the base material side of the single-sided pressure-sensitive adhesive tape was fixed to a SUS plate with a paper double-sided pressure-sensitive adhesive tape (No. 778 manufactured by Teraoka Seisakusho Co., Ltd.), and the measurement was performed.

The peeling of the copper foil was evaluated according to the following criteria. (Peeling force of copper foil during heat peeling treatment) A: Natural peeling during heating, or peeling force is less than 20% of the initial peeling force (good). B: The peeling force is 20% or more of the initial peeling force (defective). (Paste Residual Properties of Copper Foil at the Time of Heat Peeling Treatment) A: No paste remains (good). B: There is a paste residue (defective).

[Table 3-1] Table 3-1 adhesive Viscoelasticity of Adhesive Components Number of additional copies of F The maximum expansion temperature of F TFmax (℃) G'(*10^5 Pa) Tanδ 23℃ 170℃ TFmax(℃) Example 1 Ac 2.98 0.90 0.019 30 192 2 Ac 2.98 0.90 0.019 5 192 3 Ac 2.98 0.90 0.019 10 192 4 Ac 2.98 0.90 0.019 50 192 5 Ac 5.21 2.89 0.002 30 192 6 Ac 4.58 0.98 0.017 30 192 7 Ac 6.01 2.96 0.013 30 192 8 Ac 1.27 0.49 0.023 30 192 9 Ac 4.84 4.10 0.003 30 192 10 Ac 3.66 2.66 0.006 30 192 11 Ac 0.93 0.57 0.024 30 192 12 Ac 2.03 2.42 0.003 30 192 13 Si 1.47 1.26 0.053 30 192 Comparative example 1 Ac 2.98 0.90 0.019 0 192 2 Ac 2.98 0.90 0.019 3 192 3 Ac 2.98 0.90 0.029 30 162 4 Ac 2.32 0.30 0.210 30 192 5 Ac 2.39 0.40 0.126 30 192 6 Ac 4.93 0.43 0.219 30 192 7 Ac 1.64 0.29 0.039 30 192 8 Ac 2.04 0.24 0.115 30 192 9 Si 8.82 0.40 0.532 30 192

[Table 3-2] Table 3-2 [Evaluation results of acrylic double-sided heat-peelable adhesive tape] No autoclave (c) Initial stage (d) With heat stripping treatment copper foil copper plate copper foil copper plate Peeling force N/10 mm Peeling force N/10 mm Peeling force N/10 mm paste residue Peeling force N/10 mm paste residue Example 1 2.01 1.45 Natural peeling: A A Natural peeling: A A 2 3.50 2.31 Natural peeling: A A Natural peeling: A A 3 2.69 2.11 Natural peeling: A A Natural peeling: A A 4 0.83 1.19 Natural peeling: A A Natural peeling: A A 5 0.33 1.03 Natural peeling: A A Natural peeling: A A 6 1.70 1.46 Natural peeling: A A Natural peeling: A A 7 2.89 4.44 Natural peeling: A A Natural peeling: A A 8 1.99 1.06 Natural peeling: A A Natural peeling: A A 9 0.51 0.45 Natural peeling: A A Natural peeling: A A 10 0.86 0.82 Natural peeling: A A Natural peeling: A A 11 1.03 0.78 Natural peeling: A A Natural peeling: A A 12 0.25 0.26 Natural peeling: A A Natural peeling: A A Comparative example 1 5.53 3.27 5.36 (97%): B A 5.14 (157%): B A 2 3.47 2.68 Natural peeling: A A Natural peeling: A A 3 1.78 1.63 Natural peeling: A A 0.08 (5%): A A 4 3.10 1.92 4.98 (161%): B B 4.98 (259%): B B 5 3.13 2.13 1.83 (58%): B B 0.80 (38%): B B 6 2.37 1.57 3.38 (143%): B B 2.30 (146%): B B 7 2.13 1.18 Natural peeling: A A Natural peeling: A A 8 2.17 3.44 Natural peeling: A A Natural peeling: A A

[Table 3-3] [Evaluation results of acrylic double-sided heat-peelable adhesive tape] with autoclaving Comprehensive Evaluation (e) No heat stripping treatment (f) With heat stripping treatment foam suppression copper foil copper plate Peeling force N/10 mm paste residue Peeling force N/10 mm paste residue Example 1 A Natural peeling: A A Natural peeling: A A A 2 A Natural peeling: A A Natural peeling: A A A 3 A Natural peeling: A A Natural peeling: A A A 4 A Natural peeling: A A Natural peeling: A A A 5 A Natural peeling: A A Natural peeling: A A A 6 A Natural peeling: A A Natural peeling: A A A 7 A Natural peeling: A A Natural peeling: A A A 8 A Natural peeling: A A Natural peeling: A A A 9 A Natural peeling: A A Natural peeling: A A A 10 A Natural peeling: A A Natural peeling: A A A 11 A Natural peeling: A A Natural peeling: A A A 12 A Natural peeling: A A Natural peeling: A A A Comparative example 1 B 2 A 1.59 (46%): B A 0.38 (14%): A A B 3 B B 4 B 5 B 6 B 7 B B 8 B B

[Table 3-4] Table 3-4 [Evaluation results of polysiloxane heat-peelable single-sided adhesive tape] No autoclave with autoclaving Comprehensive Evaluation (g) Initial stage (h) With heat stripping treatment (i) No heat stripping treatment (j) With heat stripping treatment copper foil copper foil foam suppression copper foil Peeling force N/10 mm Peeling force N/10 mm paste residue Peeling force N/10 mm paste residue Example 13 0.52 Natural peeling: A A A Natural peeling: A A A Comparative Example 9 0.80 0.78 (38%): B B B

[evaluation result] According to the evaluation results of Tables 3-2 to 3-4, it can be seen that Examples 1 to 13 satisfying the requirements of the present invention obtained good results: even after the hot pressing step at high temperature and a long time, the peeling process was further carried out by heating. It is easy to peel off, and the paste is not easy to remain on the adherend. Furthermore, foaming of heat-expandable particles can be suppressed even during hot pressing.

In Comparative Example 1, since the thermally expansible particles are not contained in themselves, they are not easily peeled off even if the thermal peeling treatment is performed. In Comparative Example 2, when the hot pressing treatment was not performed, the peeling was facilitated by the heating peeling treatment. However, since the addition amount of the foaming agent to the adhesive component is less than 4 parts, the peeling force with respect to the copper foil assumed to be a substrate product member cannot be obtained if the heat peeling treatment is performed after hot pressing at a high temperature for a long time. fully reduced effect.

In Comparative Example 3, when the hot pressing treatment was not performed, the peeling was facilitated by the heating peeling treatment. On the other hand, since the maximum expansion temperature of the heat-expandable particles is less than 170° C., the expansion of the heat-expandable particles cannot be suppressed by hot pressing at a high temperature for a long time.

In Comparative Examples 4 to 6 and Comparative Example 9, since the tanδ of the adhesive component at the maximum expansion temperature of the thermally expansible particles was higher than 0.120, they were not easily peeled off after the heat peeling treatment even without applying high temperature and long-term pressure.

In Comparative Examples 7 to 8, since the tanδ of the adhesive component at the maximum expansion temperature of the heat-expandable particles is less than 0.120, when the heat-pressing treatment is not performed, the heat-peeling treatment is performed to facilitate the peeling. However, since the storage modulus G' at 170° C. is lower than 30,000 Pa, the expansion of the thermally expandable particles cannot be suppressed in the hot pressing at a high temperature for a long time.

For example, in Patent Document 6, the range of the storage modulus G' of the thermally expandable adhesive layer at a relatively low temperature such as 23°C or 95°C is specified, and it is possible to use it well within this range, but according to Table 3- 2 to the above evaluation results shown in Tables 3-4, it can be seen that although the storage modulus G' at normal temperature is high, the storage modulus G' at high temperature (eg 170°C) is not necessarily high. Therefore, it can be considered that the technique disclosed in Patent Document 6 is suitable for a short time at room temperature (for example, room temperature, 3MPa, 3 seconds, 100 times in the example) in the pressing step, which is not easy to shift in position, and can be easily heated by further heating It is used for peeling, but it needs to meet the parameters specified in the present invention when it is used in a high temperature and long time pressing step. In addition, Examples 1 to 3 described in Patent Document 6 use low-temperature-expandable thermally expandable particles (according to the examples described in the specification of Patent Document 6, foaming started at 120°C, and foaming and peeling occurred at 130°C) ), it can be assumed that the foaming of the heat-expandable particles cannot be suppressed if a high temperature (for example, 170° C.) autoclave treatment is performed. (Industrial Availability)

The heat-peelable adhesive tape of the present invention can be effectively used in the manufacturing steps of electronic parts or semiconductor parts, such as temporary fixing of parts, fixing during transportation, reinforcement, protection, shielding, resin sealing and other steps that require high temperature heating. In particular, it is very useful in a step such as a curing step of a sealing resin, which requires easy peeling after a pressing step at a high temperature and a long time without leaving a paste.

1: Thermal peel adhesive sheet 2: Substrate 3: Thermal expansion adhesive layer 4: Release liner

FIG. 1 is a cross-sectional view in the thickness direction schematically showing an example of the structure of the thermally peelable adhesive tape of the present invention.

1: Thermal peel adhesive sheet 2: Substrate 3: Thermal expansion adhesive layer 4: Release liner

Claims (13)

A heat-peelable adhesive tape having a heat-expandable adhesive layer comprising an adhesive component and heat-expandable particles, wherein the heat-expandable adhesive layer contains 4 parts by mass or more relative to 100 parts by mass of the adhesive component. The thermally expandable particles, wherein the maximum expansion temperature of the thermally expandable particles is 170°C or higher, in the dynamic viscoelasticity measurement of the adhesive component (temperature range -60°C to 300°C, heating rate 10°C/min, frequency 10Hz), (1) The tanδ at the maximum expansion temperature of the heat-expandable particles is 0.120 or less, and (2) the storage modulus G' at 170°C is 30,000 Pa or more, and the adhesive components are acrylic adhesives, rubber-based adhesives Any one of the adhesive and the polysiloxane-based adhesive. The heat-peelable adhesive tape according to claim 1, which contains 5 parts by mass or more of the heat-expandable particles with respect to 100 parts by mass of the resin component contained in the heat-expandable adhesive layer. The heat-peelable adhesive tape according to claim 1, wherein the heat-expandable particles are contained in a ratio of 7 parts by mass or more and less than 80 parts by mass relative to 100 parts by mass of the resin component contained in the heat-expandable adhesive layer. The thermally peelable pressure-sensitive adhesive tape according to claim 1, wherein the maximum thermal expansion temperature of the thermally expandable particles is 180°C or higher and 320°C or lower. The heat-peelable adhesive tape according to claim 1, wherein the tanδ is 0.001 or more and 0.110 or less, and the storage modulus G' is 40,000Pa or more and 1,000,000Pa the following. The heat-peelable adhesive tape of claim 1, which has a heat-expandable adhesive layer on at least one side of the base material. The heat-peelable adhesive tape of claim 1, which has the above-mentioned heat-expandable adhesive layer on both sides of the base material. The heat-peelable adhesive tape according to claim 6 or 7, wherein the base material is a resin film. The heat-peelable adhesive tape of claim 8, wherein the base material is a polyimide film. The heat-peelable adhesive tape of claim 1, which is used to temporarily fix the adherend to the adherend in the heat-pressing step of the adherend. The heat-peelable adhesive tape of claim 10, wherein the above-mentioned hot-pressing step comprises a hot-pressing step of a temperature of 120-240° C., a time of 5 minutes to 10 hours, and a pressure of 5-40 kgf/cm ² . After the hot-pressing step The peeling force of the adherend is significantly reduced by heating for peeling. A method of using a heat-peelable adhesive tape, which is a method of using the heat-peelable adhesive tape in a hot-pressing treatment of an adherend, characterized by comprising: temporarily fixing the heat-peelable adhesive tape of claim 1 to the adherend the step of heat-pressing the above-mentioned adherend temporarily fixed with the adhesive tape; the step of heating the heat-peelable adhesive tape temporarily fixed to the above-mentioned heat-pressed adherend to a temperature for peeling; and The above-mentioned heat-peelable adhesive tape heated to the temperature for peeling is peeled from the above-mentioned adherend. step. The method for using the heat-peelable adhesive tape of claim 12, wherein the hot-pressing step includes a hot-pressing step at a temperature of 120-240° C., a time of 5 minutes to 10 hours, and a pressure of 5-40 kgf/cm ² .

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