WO2018123615A1 - Adhesive tape, article, and article manufacturing method - Google Patents

Abstract

The present invention addresses the problem of providing an adhesive tape: that possesses superior adhesiveness before being heated; that can be expanded by being heated; and that is capable of exhibiting superior adhesiveness even after being heated and expanded. The present invention is an adhesive tape that is used for the purpose of filling a gap that an adherend (C1) has or a gap between an adherend (C1) and an adherend (C2), the adhesive tape being characterized in that the adhesive tape includes a thermoplastic heat-expandable adhesive layer (A), and that the rate of expansion of the thermoplastic heat-expandable adhesive layer (A) in a thickness direction, that is, ([thickness of thermoplastic heat-expandable adhesive layer (A1) after being heated]/[thickness of thermoplastic heat-expandable adhesive layer (A) before being heated])×100, is equal to or greater than 150%.

Description

Adhesive tape, article and method for producing article

This invention relates to the adhesive tape provided with the structure which can expand | swell in the thickness direction by giving irritation | stimulation of heating etc. for a short time at low temperature.

In general, the adhesive tape can be suitably used for fixing one adherend to a flat surface portion or a curved surface portion of the other adherend, such as an automobile member or an electric device. Widely used in various product manufacturing scenes.

On the other hand, the use range of the adhesive tape is expected to expand further, and the adhesive tape is suitable for the case where, for example, the other adherend is fixed in the gap of one adherend. It is demanded that it can be used. Specifically, as a motor mounted on a hybrid vehicle or the like, a motor having a configuration in which a magnet is embedded in a predetermined position (gap) of a core part (rotor core) is generally known. It has been studied to use the adhesive tape when fixing the magnet in the gap of the.

The adhesive tape that can be used in the above application is formed on the first surface of the base material having a first surface and a second surface on the opposite side of the first surface and having a communication port, for example. A first adhesive layer containing a thermosetting thermally expandable epoxy adhesive, and the thermosetting thermally expandable epoxy adhesive passes through the communication port of the substrate when heated, and A thermosetting thermally expandable adhesive sheet that forms a second adhesive layer on the second surface is known (see, for example, Patent Document 1).

However, since the thermosetting adhesive tape does not have a sufficient adhesive force before heating, the thermosetting adhesive tape is temporarily attached (temporarily bonded) to a predetermined position of the adherend before heating. Even when it is difficult or when it can be temporarily attached, the thermosetting adhesive tape may be displaced from the adherend.

JP 2010-023559 A

The problem to be solved by the present invention is to provide an adhesive tape that has an excellent adhesive force before heating, can be expanded by heating, and can exhibit an excellent adhesive force even after heating and expansion.

The inventors of the present invention are adhesive tapes used for filling the voids of the adherend (C1) or the gaps between the adherend (C1) and the adherend (C2), The adhesive tape has a thermoplastic heat-expandable adhesive layer (A), and the expansion coefficient in the thickness direction of the thermoplastic heat-expandable adhesive layer (A) [thermoplastic heat-expandable adhesive after heating The thickness of the layer (A1) / the thickness of the thermoplastic heat-expandable adhesive layer (A) before heating] × 100 is 150% or more.

Since the adhesive tape of the present invention has an excellent adhesive force, it can be applied to an accurate position of the adherend even before heating, and causes a shift in the adhesive tape application position after temporary application. Therefore, the voids of the adherend and the gaps between two or more adherends can be sufficiently filled or bonded.

It is a conceptual diagram which shows the measuring method of a shearing adhesive force.

The adhesive tape of the present invention is an adhesive tape used in an application for filling a gap of the adherend (C1) or a gap between the adherend (C1) and the adherend (C2), The adhesive tape has a thermoplastic heat-expandable adhesive layer (A), and the expansion coefficient in the thickness direction of the thermoplastic heat-expandable adhesive layer (A) [thermoplastic heat-expandable adhesive after heating The thickness of the agent layer (A1) / the thickness of the thermoplastic heat-expandable adhesive layer (A) before heating] × 100 is 150% or more.

The adhesive tape of the present invention uses at least the thermoplastic thermally expandable adhesive layer (A).
Examples of the adhesive tape include an adhesive tape constituted by a single layer or two or more layers of the thermoplastic heat-expandable adhesive layer (A), the thermoplastic heat-expandable adhesive layer (A), and other expandable materials. Adhesive tape composed of an adhesive layer (for example, a photoexpandable adhesive layer or a thermosetting expandable adhesive layer), the thermoplastic thermal expandable adhesive layer (A) and an adhesive layer that is difficult to expand For example, the adhesive tape etc. comprised by (For example, the adhesive bond layer (B) mentioned later etc.) are mentioned.
Among these, as the adhesive tape, it is possible to use an adhesive tape constituted by the thermoplastic thermally expandable adhesive layer (A) and the other adhesive layer, and the adherend (C1) has a void. Alternatively, it is preferable for filling the space between the adherend (C1) and the adherend (C2) with the expanded product of the adhesive tape and firmly bonding the gap.

As an adhesive tape constituted by the thermoplastic heat-expandable adhesive layer (A) and other adhesive layers, specifically, at least one of the thermoplastic heat-expandable adhesive layers (A) It is preferable to use what has the adhesive bond layer (B) mentioned later on the surface. As the adhesive tape, the thermoplastic heat-expandable adhesive layer (A) may be applied in advance to the adherend before the expansion, and the thermoplastic heat-expandable adhesive layer (A1) after the expansion and It is preferable for maintaining excellent adhesion with the adherend.

(Thermoplastic thermally expandable adhesive layer (A))
The thermoplastic heat-expandable adhesive layer (A) is a layer that can expand by heating, for example. The thermoplastic heat-expandable adhesive layer (A) includes an expansion coefficient in the thickness direction of the thermoplastic heat-expandable adhesive layer (A) [the thermoplastic heat-expandable adhesive layer after the standing after heating ( Thickness of A) / thickness of thermoplastic heat-expandable adhesive layer (A) before standing] × 100 is 150% or more. The expansion coefficient is preferably 200% or more, and more preferably 250% to 1000%. With such an adhesive tape, the height (thickness) of the gap between the adherend (C1) or the gap between the adherend (C1) and the adherend (C2) is large. However, by expanding the adhesive tape, the other adherend can be suitably fixed in the gap, or the gap can be filled with the adhesive tape. Further, with the adhesive tape, even if the surface of the adherend is a rough surface, the other adherend can be suitably fixed to the rough surface.
The expansion rate is relative to the thickness of the thermoplastic thermally expandable adhesive layer (A) before standing (before expansion) when the adhesive tape is left at a temperature of 50 ° C. to 150 ° C. for 30 minutes. The ratio of the thickness of the thermoplastic heat-expandable adhesive layer (A1) formed by the expansion of the thermoplastic heat-expandable adhesive layer (A) by the above-mentioned standing is indicated at a temperature of 60 ° C. to 145 ° C. The temperature is preferably 70 ° C to 140 ° C.

The thermoplastic heat-expandable adhesive layer (A) is drawn at a speed of 300 mm / min in the direction of 180 degrees in order to provide a level of adhesiveness that can be temporarily attached to an adherend even before heating. It is preferable to use one having an adhesive strength of 0.5 N / 20 mm or more when peeled, more preferably one having 1 N / 20 mm or more, and one having 2 N / 20 mm or more being used. More preferably, it is more preferably 3N / 20 mm or more in order to prevent the adhesive tape from peeling off or being displaced from the adherend.

The thickness of the thermoplastic heat-expandable adhesive layer (A) before expansion is preferably in the range of 10 μm to 250 μm, more preferably in the range of 20 μm to 150 μm, and in the range of 30 μm to 100 μm. This is preferable in that it can provide a level of adhesiveness that can be temporarily attached to the adherend even before heating, and prevents the adhesive tape from peeling off or being displaced from the adherend.

On the other hand, the thickness of the thermoplastic heat-expandable adhesive layer (A1) formed by the expansion of the thermoplastic heat-expandable adhesive layer (A) is preferably in the range of 20 μm to 2500 μm, preferably 40 μm. A range of ˜1500 μm is preferable for obtaining a further excellent adhesive force. Moreover, it is preferable that the said thermoplastic heat-expandable adhesive bond layer (A1) has a porous structure.

Further, as the adhesive tape, it is preferable to use a tape in which the thickness of the thermoplastic thermally expandable adhesive layer (A) is 10% or more with respect to the total thickness of the adhesive tape, and 30% It is more preferable to use what is described above because the other adherend is suitably fixed in the gap or the gap is easily filled with the adhesive tape.
As said thermoplastic heat-expandable adhesive layer (A), it has the adhesive force of the grade which can be beforehand adhere | attached on a to-be-adhered body as above-mentioned, and when the said thermoplastic heat-expandable adhesive layer (A) expand | swells, A material that can fill and bond the voids of the adherend (C1) or the voids between the adherend (C1) and the adherend (C2) with the applied pressure is used.

The thermoplastic heat-expandable adhesive layer (A) can be produced by, for example, applying an adhesive composition (a), which will be described later, to a release liner or a pressure-sensitive adhesive tape support and drying. .

The thermoplastic thermally expandable adhesive layer (A) can be formed using an adhesive composition (a) containing a thermoplastic resin. The content of the thermoplastic resin is preferably 50% by mass or more, more preferably 75% by mass or more, and still more preferably 90% by mass or more with respect to the total solid components of the adhesive composition (a).

As the thermoplastic resin, a resin that can be easily expanded by heating can be used.
As the thermoplastic resin, one having a storage elastic modulus G ₂₃ measured by a dynamic viscoelastic spectrum at 1 Hz and 23 ° C. in the range of 1.0 × 10 ³ to 5.0 × 10 ⁷ Pa is used. It is preferable that a storage elastic modulus G ₇₀ measured by a dynamic viscoelastic spectrum at 1 Hz and 70 ° C. is in the range of 1.0 × 10 ² to 1.0 × 10 ⁷ Pa. It is preferable that a storage elastic modulus G ₁₂₀ measured by a dynamic viscoelastic spectrum at 1 Hz and 120 ° C. is in the range of 1.0 × 10 ² to 1.0 × 10 ⁶ Pa. It is particularly preferable to obtain an adhesive tape that can prevent the adhesive tape from being peeled off or displaced from the adherend even before heating and can expand to a level that can sufficiently fill the gap.

The adhesive tape in the state before expanding the thermoplastic heat-expandable adhesive layer (A) can prevent the adhesive tape from peeling off or being displaced from the adherend even before heating, and at room temperature after expansion. storage modulus _{G 23} which in order to suppress the contraction under the circumstances is measured by a dynamic viscoelasticity spectrum at 1Hz and 23 ° C. is preferably ^{1.0 × 10 3 ~ 5.0 × 10} 7 Pa, more preferably May be those containing a thermoplastic resin of 5.0 × 10 ³ to 1.0 × 10 ⁷ Pa, particularly preferably 5.0 × 10 ³ to 5.0 × 10 ⁶ Pa.

Further, the thermoplastic resin, which has a storage modulus G ₂₃ as measured by dynamic viscoelasticity spectrum at 1Hz and 23 ° C. within the above range, dynamic at 1Hz in the range of 70 ° C. ~ 120 ° C. Use of a material having a storage elastic modulus measured by a viscoelastic spectrum in the range of 1.0 × 10 ² Pa to 1.0 × 10 ⁷ Pa in the plane direction (flow direction or width direction) of the adhesive tape. It is preferable for suppressing the expansion of the film and expanding in the thickness direction.
As the thermoplastic resin, a storage elastic modulus G ₇₀ measured by a dynamic viscoelastic spectrum at 1 Hz and 70 ° C. is preferably 1.0 × 10 ² to 1.0 × 10 ⁷ Pa, more preferably 5. A material having a viscosity of 0 × 10 ² to 5.0 × 10 ⁶ Pa, particularly preferably 5.0 × 10 ² to 1.0 × 10 ⁶ Pa can be used.
Further, as the thermoplastic resin, a storage elastic modulus G ₇₀ measured by a dynamic viscoelastic spectrum at 1 Hz and 70 ° C. is preferably 1.0 × 10 ² to 1.0 × 10 ⁷ Pa, more preferably 5.0 × 10 ² to 5.0 × 10 ⁶ Pa, particularly preferably 5.0 × 10 ² to 1.0 × 10 ⁶ Pa can be used.

Further, the storage elastic modulus G ₁₂₀ measured by a dynamic viscoelastic spectrum at 1 Hz and 120 ° C. of the thermoplastic resin is preferably 1.0 × 10 ² to 1.0 × 10 ⁶ Pa. It is more preferably 0.0 × 10 ² to 5.0 × 10 ⁶ Pa, and even more preferably 5.0 × 10 ² to 2.0 × 10 ⁵ Pa.

The storage elastic modulus G ₁₂₀ of the thermoplastic resin is smaller it is preferable than the storage elastic modulus G _70, the storage elastic modulus G _70, it is preferable that the smaller than the storage modulus G _23.

The measurement of the storage modulus G _23, G ₇₀ and G ₁₂₀ are using a commercial viscoelastic tester, was measured by the method described in the examples below. The test piece for the measurement was obtained by heating the thermoplastic resin (excluding the expansion agent) contained in the thermoplastic thermally expandable adhesive layer (A), applying it on the release liner, and cooling it. A test piece with a thickness of 2 mm is used.

The thermoplastic resin has, for example, excellent adhesive strength before expansion, softens at the expansion start temperature of the expansion agent, the expansion agent easily expands, and can exhibit excellent adhesive strength even after expansion Is preferably used.
Examples of the thermoplastic resin include urethane resins such as polyurethane (PU) and thermoplastic polyurethane (TPU); polycarbonate (PC); polyvinyl chloride (PVC) and vinyl chloride such as vinyl chloride-vinyl acetate copolymer resin. Resins such as polyacrylic acid, polymethacrylic acid, polymethyl acrylate, polymethyl methacrylate (PMMA) and polyethyl methacrylate; polyethylene terephthalate (PET), polybutylene terephthalate, Polyester resins such as polytrimethylene terephthalate, polyethylene naphthalate, and polybutylene naphthalate; Polyamide resins such as nylon (registered trademark); Polystyrene (PS), Imido-modified polystyrene, Acrylonitrile butadiene, Styrene (ABS) resin, imide ABS resin, styrene / acrylonitrile copolymer (SAN) resin, polystyrene resin such as acrylonitrile / ethylene-propylene-diene / styrene (AES) resin, polyethylene (PE) resin, polypropylene (PP) resin, cycloolefin resin, etc. Olefin resins; Cellulosic resins such as nitrocellulose and cellulose acetate; Silicone resins; Thermoplastic resins such as fluororesins, Styrenic thermoplastic elastomers, Olefin thermoplastic elastomers, Vinyl chloride thermoplastic elastomers, Urethane heat Examples include thermoplastic elastomers such as plastic elastomers, ester-based thermoplastic elastomers, and amide-based thermoplastic elastomers.
Among these thermoplastic resins, among them, styrene thermoplastic elastomer, olefin thermoplastic elastomer, vinyl chloride thermoplastic elastomer, ester thermoplastic elastomer, urethane thermoplastic elastomer, amide thermoplastic elastomer or acrylic It is preferable to use a styrene resin or the like, and it is particularly preferable to use a styrene thermoplastic elastomer or an acrylic resin.

Styrenic thermoplastic elastomers include, for example, styrene AB type diblock copolymers such as styrene-ethylene-butylene copolymer (SEB); styrene-butadiene-styrene copolymer (SBS), hydrogenated product of SBS (Styrene-ethylene-butylene-styrene copolymer (SEBS)), styrene-isoprene-styrene copolymer (SIS), hydrogenated product of SIS (styrene-ethylene-propylene-styrene copolymer (SEPS)), styrene -Styrenic ABA type triblock copolymer such as isobutylene-styrene copolymer (SIBS); Styrene type ABAB type tetrablock copolymer such as styrene-butadiene-styrene-butadiene (SBSB); Styrene-butadiene-styrene- Butadiene-styrene (SBSBS) Styrene-based ABABA type pentablock copolymer; Styrenic multi-block copolymer having AB repeating units higher than these; Hydrogenating ethylenic double bond of styrene-based random copolymer such as styrene-butadiene rubber (SBR) And the like. A commercially available styrene thermoplastic elastomer may be used.

As said acrylic resin, what is obtained by superposing | polymerizing the monomer containing an alkyl (meth) acrylate can be used, for example.
As the alkyl (meth) acrylate, a (meth) acrylate having an alkyl group having 4 to 12 carbon atoms is preferably used. Specifically, butyl (meth) acrylate, isooctyl (meth) acrylate, 2- Ethylhexyl (meth) acrylate or the like is preferably used, and butyl acrylate and 2-ethylhexyl acrylate are more preferably used alone or in combination.
In addition to those described above, acrylonitrile, (meth) acrylic acid, maleic anhydride, acrylamide, itaconic acid, styrene, vinyl acetate and the like can be used as the monomer.

The adhesive composition (a) may contain a thermosetting resin. As the thermosetting resin, urethane resin, phenol resin, unsaturated polyester resin, epoxy resin, acrylic resin and the like can be used. Among them, for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, hindered-in type epoxy resin, biphenyl type epoxy resin, alicyclic epoxy resin, triphenylmethane type epoxy resin, phenol novolac type epoxy resin , Cresol novolac epoxy resin, naphthol novolac epoxy resin, dicyclopentadiene / phenol epoxy resin, cycloaliphatic amine epoxy resin, aliphatic amine epoxy resin, and CTBN modified (carboxy terminated butadiene nitrile modified) and halogen modified These epoxy resins can be used alone or in combination of two or more.
The content of the thermosetting resin is preferably 50% by mass or less, more preferably 25% by mass or less, and still more preferably 10% by mass or less with respect to the total solid components of the adhesive composition (a).

The adhesive composition (a) may contain a swelling agent. As the expansion agent, it is preferable to use one that can form a porous structure as the thermoplastic thermally expandable adhesive layer (A1) after expansion. For example, ammonium carbonate, ammonium hydrogen carbonate, ammonium nitrite, ammonium borohydride, Inorganic compounds such as azide, fluorinated alkanes such as trichloromonofluoromethane, azo compounds such as azobisisobutyronitrile, hydrazine compounds such as paratoluenesulfonyl hydrazide, semicarbazide compounds such as p-toluenesulfonyl semicarbazide, 5-morpholyl- Triazole compounds such as 1,2,3,4-thiatriazole and N-nitroso compounds such as N, N′-dinitrosotephthalamide can be used.

The expansion agent is preferably a thermal expansion agent that expands by heat. For example, an expansion capsule such as a thermal expansion capsule in which a hydrocarbon solvent is microencapsulated can be used. As the thermal expansion agent, it is preferable to use a material that generates gas and expands at a temperature around the softening point of the thermoplastic resin. The expansion start temperature of the thermal expansion agent is preferably 50 ° C. or higher, more preferably 60 ° C. or higher, and 70 ° C. or higher is excellent in stability during storage and has heat resistance. It is preferable because the adhesive tape can be sufficiently expanded without damaging the adherend having a low thickness and an excellent adhesive force can be obtained after the expansion.
Among the above-mentioned expansion agents, it is possible to use a thermally expandable capsule in which a hydrocarbon solvent is microencapsulated among the above-mentioned, for example, deterioration of the thermoplastic thermally expandable adhesive layer (A) due to the influence of heat or the like. It is more preferable in preventing. The above-mentioned swelling agents can be used alone or in combination of two or more.

Examples of commercially available thermal expandable capsules include EXPANSEL (manufactured by Nippon Philite Co., Ltd.), Matsumoto Microsphere (manufactured by Matsumoto Yushi Seiyaku Co., Ltd.), and Microsphere (manufactured by Kureha Co., Ltd.).
Examples of the thermally expandable capsule include Matsumoto Microsphere F-30, F-36, F-36D, F-36LV, F-48, F-48D, F-50, FN-80GS, Matsumoto Yushi Seiyaku Co., Ltd. The use of F-65, EXPELLCELL 053-40, 007-40, 031-40, etc. manufactured by Nippon Philite Co., Ltd. expands around the temperature at which the thermoplastic resin softens. Or in the width direction), which is preferable because it can be more effectively expanded in the thickness direction.
As the thermally expandable capsule, it is preferable to use a capsule whose volume after expansion (volume expansion coefficient) is 8 to 60 times the volume of the capsule before expansion.

The amount of the expansion agent used, preferably the amount of the thermally expandable capsule, is in the range of 0.3 to 30 parts by mass with respect to 100 parts by mass of the solid content of all components of the layer (A). Preferably, it is in the range of 1 to 20 parts by weight, more preferably in the range of 3 to 17 parts by weight, and in the range of 5 to 15 parts by weight. It is further preferable in that it can expand sufficiently to fill the voids of the material, and can obtain an even better adhesive force.

As the adhesive composition (a), those containing a tackifier, a crosslinking agent, a curing agent, a curing accelerator and the like can be used as necessary in addition to the above-described ones.

(Adhesive layer (B))
Moreover, as above-mentioned, as an adhesive tape of this invention, it is preferable to use what has an adhesive bond layer (B).
As an adhesive layer (B) which comprises the said adhesive tape, it can form using the adhesive composition (b) which can form the layer which has adhesiveness or adhesiveness.

As the adhesive layer (B), the expansion rate in the thickness direction of the adhesive layer (B) [the thickness of the adhesive layer (B) after being left after heating / the adhesive layer before being left ( Thickness of B)] × 100 of 120% or less can be used. The expansion ratio of the adhesive layer (B) is preferably 115% or less, and more preferably 110% or less. With such an adhesive tape, even after the thermoplastic heat-expandable adhesive layer (A) is expanded, it is possible to maintain an excellent adhesive force to the adherend. It should be noted that the expansion rate of the adhesive layer (B) is determined after the standing relative to the thickness of the adhesive layer (B) before leaving when the adhesive tape is left in an environment of 100 ° C. for 30 minutes. It refers to the ratio of the thickness of the adhesive layer.

The thickness of the adhesive layer (B) is preferably in the range of 1 μm to 150 μm, and is preferably in the range of 5 μm to 100 μm, so that the thermoplastic thermally expandable adhesive layer (A) constituting the adhesive tape Expands and fills the voids of the adherend (C1) or the gap between the adherend (C1) and the adherend (C2), and the adhesive layer (B) adheres to the adherend ( C2) is more preferable because it can exhibit excellent adhesive force when attached to C2.

Since it is preferable that the adhesive layer (B) has a low expansion coefficient as described above, the expansion agent exemplified as being usable when forming the thermoplastic thermally expandable adhesive layer (A) is substantially used. It is preferable that it is not contained.
As the adhesive (B), for example, an adhesive composition (b) containing a resin such as a thermosetting resin or a thermoplastic resin and containing little or no content of the expansion agent is preferably used. it can.
As a resin that can be used for the adhesive composition (b), a conventionally known resin can be selected and used. Among them, the resin contains an adhesive composition (a) that can be used, for example, for forming the thermoplastic thermally expandable adhesive layer (A) in order to improve the production efficiency of the adhesive tape of the present invention. It is preferable to use those similar to those exemplified as the thermoplastic resin.

As the adhesive composition (b), for example, one containing a resin such as the thermoplastic resin and, if necessary, a tackifier resin, a crosslinking agent, other additives, and the like can be used.

Examples of the tackifying resin include a rosin-based tackifying resin, a polymerized rosin-based tackifying resin, a polymerized rosin ester-based tackifying resin, and a rosin phenol for the purpose of adjusting the strong adhesiveness of the adhesive layer (B). Tackifying resins, stabilized rosin ester tackifying resins, disproportionated rosin ester tackifying resins, terpene tackifying resins, terpene phenol tackifying resins, petroleum resin tackifying resins, etc. can be used. .

Examples of the crosslinking agent include known isocyanate crosslinking agents, epoxy crosslinking agents, aziridine crosslinking agents, polyvalent metal salt crosslinking agents, metal chelates for the purpose of improving the cohesive strength of the adhesive layer (B). A cross-linking agent, a keto-hydrazide cross-linking agent, an oxazoline cross-linking agent, a carbodiimide cross-linking agent, a silane cross-linking agent, a glycidyl (alkoxy) epoxy silane cross-linking agent, or the like can be used.

Examples of the additive include a base for adjusting pH (such as aqueous ammonia), an acid, a foaming agent, a plasticizer, a softening agent, an antioxidant, as long as the desired effect of the present invention is not inhibited as necessary. Glass or plastic fiber, balloon, bead, metal powder fillers, pigments, colorants such as dyes, pH adjusters, film formation aids, leveling agents, thickeners, water repellents, water A well-known thing, such as a foaming agent, can be used.

As the adhesive composition (b), one containing a solvent can be used for maintaining good coating workability. As the solvent, for example, toluene, xylene, ethyl acetate, butyl acetate, acetone, methyl ethyl ketone, hexane and the like can be used. Moreover, when using an aqueous adhesive composition as the adhesive composition (b), water or an aqueous solvent mainly composed of water can be used as the solvent.

The adhesive tape of the present invention is produced, for example, by passing through the step [I] of forming the thermoplastic thermally expandable adhesive layer (A) by applying the adhesive composition (a) to a release liner and drying it. can do.
Among the adhesive tapes of the present invention, the adhesive tape constituted by the thermoplastic thermally expandable adhesive layer (A) and the adhesive layer (B) includes the step [I], the step [I], Separately, the step [II] of forming the adhesive layer (B) by applying the adhesive composition (b) to a release liner and drying, and the thermoplastic thermally expandable adhesive layer (A) The adhesive layer (B) can be transferred to one side of the film and subjected to a step [III] for pressure bonding or the like.
In addition, it is preferable that the said thermoplastic heat-expandable adhesive bond layer (A) does not expand | swell substantially in the process of manufacturing the said adhesive tape.

Moreover, as an adhesive tape of this invention, as needed, the layer (Z) which consists of a nonwoven fabric layer, a resin film layer, or a metal between the said thermoplastic thermal expansible adhesive layer (A) and an adhesive bond layer (B). ) Can be used. Since such an adhesive tape has good rigidity, it is excellent in sticking workability.

As the layer (Z), for example, if it is a non-woven fabric, the material is preferably made of pulp, rayon, manila hemp, acrylonitrile, nylon, polyester, etc. In addition, a one-step impregnation treatment in which polyamide is added and coating after drying, a two-step impregnation treatment using viscose or a thermoplastic resin as a binder may be performed. As a resin film, a polyester film, a polyethylene film, a polypropylene film, a polyvinyl chloride film, a resin film layer formed using a plastic film such as a polyimide film, etc., and as a layer made of metal, a metal layer such as aluminum or copper Is mentioned.

It is preferable to use a layer having a thickness of 1 μm to 200 μm as the layer (Z).

The adhesive tape having the layer (Z) is, for example, a step [I] of forming the thermoplastic thermally expandable adhesive layer (A) by applying the adhesive composition (a) to a release liner and drying it. Separately from the step [I], the adhesive composition (b) is applied to a release liner and dried to form the adhesive layer (B) [II], the thermoplastic thermal expansion adhesive Step [IV] of laminating the layer (Z) on one side of the agent layer (A), and Step of transferring the adhesive layer (B) to the surface comprising the layer (Z) and pressing them together [ V] can be used for manufacturing.

Since the adhesive tape of the present invention obtained by the above method can be expanded by heating and has an excellent adhesive force, it is exclusively the void of the adherend (C1) or the adherend (C1) and the adherend. The space between the bonded body (C2) can be suitably used in the production scene of an article filled or bonded with the expanded product of the adhesive tape of the present invention.
As a method for producing the article, for example, the thermoplastic thermally expandable adhesive layer (A) or the adhesive layer (B) of the adhesive tape is applied to the part (c1-1) constituting the adherend (C1). Step [1] of heating, Step [2] of heating the thermoplastic heat-expandable adhesive layer (A), The thermoplastic heat-expandable adhesive layer (A) is expanded by the heating, and the thermoplastic heat-expandable Step [3] in which the adhesive layer (A1) is formed, and the thermoplastic thermally expandable adhesive layer (A1) or the adhesive layer (B) constituting the adhesive tape are the adherend (C1). And a method for producing an article having the step [4] applied to another part (c1-2) or another adherend (C2) constituting the structure.

In the step [1], the thermoplastic heat-expandable adhesive layer (A) or the adhesive layer (B) of the adhesive tape is added to the site (c1-1) constituting the adherend (C1) at 0.1 N / Bonding with a force of cm ² or more increases the adhesive force of the adhesive tape to the part (c1-1) constituting the adherend (C1), and even before heating, the adhesive tape and the adherend ( This is preferable because deviation from C1) can be suppressed.

Necessary when pressure-bonding the thermoplastic thermally expandable adhesive layer (A) or the adhesive layer (B) of the adhesive tape to the part (c1-1) constituting the adherend (C1). Accordingly, devices such as a press and a roller may be used, or they may be pressed with a finger.

The heating temperature in the step [2] is preferably, for example, a temperature corresponding to the temperature at which the expansion agent expands (expansion start temperature), specifically 50 to 150 ° C., preferably 60 to 145 ° C. is more preferable, and 70 to 140 ° C. is excellent in stability during storage, and the adhesive tape can be sufficiently expanded without damaging the adherend having low heat resistance, and excellent after expansion. It is preferable because an adhesive force can be obtained.
Examples of the heating method include a method in which the article is put into a heating device such as an oven or a heating furnace and the entire article is heated, the thermoplastic thermally expandable adhesive layer (A), the adhesive tape, or the deposition. A method of heating the thermoplastic heat-expandable adhesive layer (A) by bringing a heat source into contact with or approaching the body is mentioned.
As the heat source, for example, a halogen lamp, a laser irradiation device, an electromagnetic induction heating device, a hot stamp, a hot plate, a soldering iron, or the like can be used. The heating method can be selected depending on the size of the article.
The adhesive tape of the present invention preferably expands in the thickness direction after the heating, and preferably does not substantially expand in the flow direction or the width direction.

In the step [2], the thermoplastic thermally expandable adhesive layer (A) expands to form a thermoplastic thermally expandable adhesive layer (A1) (step [3]). The thermoplastic heat-expandable adhesive layer (A1) expands mainly in the thickness direction of the adhesive tape due to the expansion.

In the step [4], the adhesive layer (A1) or the adhesive layer (B) and the adherend (by the force generated by expanding the thermoplastic thermally expandable adhesive layer (A)) and the adherend ( The other part (c1-2) or the other adherend (C2) constituting C1) is pressure-bonded. Therefore, it is necessary to apply pressure using, for example, a press machine or the like when filling the voids of the adherend (C1) or the gaps between the adherend (C1) and the adherend (C2). Absent. In addition, since the adhesive tape and the adherend are brought into close contact with each other by the force generated by the expansion, the adhesive tape is used even when the adherend has an uneven surface (having a rough surface). It is difficult to form a gap between the substrate and the adherend.
Examples of the adherends (C1) and (C2) include metals such as glass and aluminum, and plastics made of resin such as acrylic and polycarbonate. As said adherend (C1) and (C2), what consists of the same material and shape may be used, and the thing of a different material and shape may be used.
As said adherends (C1) and (C2), the surface which the said thermoplastic heat-expandable adhesive layer (A) and the said adhesive bond layer (B) contact may be a rough surface.

The shape of the adherend (C1) and the adherend (C2) is not particularly defined, and examples thereof include a two-dimensional shape, a three-dimensional shape (curved surface, etc.), a shape having surface irregularities, and a fitting shape. It is done. A combination of the above shapes may also be used.

The adhesive tape of the present invention can be expanded by applying heat to the thermoplastic thermally expandable adhesive layer (A) or the entire adhesive tape.

As the method for producing the article, the steps [1], [2] and [3] are performed in this order, and have excellent adhesive force before heating, can be expanded by heating, and heated. It is preferable for exhibiting excellent adhesive force even after expansion. In particular, when the surface of the adherend (C1) or (C2) is a rough surface, it is effective in expressing good adhesive force.
For example, even when an adhesive tape that has been heated and expanded in advance through the step [2] is used to attach to an adherend with surface irregularities, a fine gap is formed at the interface between them. The possibility of being reduced can be reduced.

Examples of the article obtained by the above method include a small motor mounted on a movable part of an automobile. The motor is generally composed of an exterior member (cylindrical member) and a lid-like member. As the motor, specifically, a metal cylindrical member and a resin lid-shaped member having a shape corresponding to the cylindrical member are fixed in a fitted state. The adhesive tape of this invention can be filled with the space | gap which may be formed between the said cylindrical member and the said lid-shaped member.

(Preparation Example 1)
<Preparation of adhesive composition (a-1)>
Styrene-butadiene block copolymer S having a weight average molecular weight of 300,000 (mixture of triblock copolymer and diblock copolymer. The proportion of the diblock copolymer in the total amount of the mixture is 50% by mass. The mass ratio of polystyrene units to the entire styrene-butadiene block copolymer is 30 mass%, the mass ratio of polybutadiene units is 70 mass%), 100 parts by mass, terpene phenol-based tackifier resin (softening point 115 ° C., molecular weight 1000). An adhesive composition (a-1) was obtained by dissolving a mixture of 65 parts by mass in toluene.

(Preparation Example 2)
<Preparation of adhesive composition (a-2)>
Adhesive composition in the same manner as in Preparation Example 1 except that the amount of the terpene phenol-based tackifying resin (softening point 115 ° C., molecular weight 1000) used in Preparation Example 1 was changed from 65 parts by mass to 100 parts by mass. (A-2) was obtained.

(Preparation Example 3)
<Preparation of adhesive composition (a-3)>
Instead of the styrene-butadiene block copolymer S, a styrene-isoprene block copolymer T having a weight average molecular weight of 200,000 (a mixture of a triblock copolymer and a diblock copolymer. The diblock relative to the total amount of the mixture) The proportion of copolymer is 52% by mass, the proportion of polystyrene units in the total of the styrene-isoprene block copolymer is 15% by mass, the proportion of polyisoprene units is 85% by mass), 100 parts by mass, terpene phenol 40 parts by mass of C5 petroleum-based tackifier resin (softening point 100 ° C., number average molecular weight 885), 30 parts by mass of polymerized rosin ester-based tackifier resin (softening point 125 ° C., number average molecular weight 880), HV-100 as a liquid tackifying resin (manufactured by JX Nippon Oil & Energy Corporation, low molecular weight polyb Down) except for using 5 parts by weight was obtained in the same manner as in Preparation Example 1 adhesive compositions (a-3).

(Preparation Example 4)
<Preparation of adhesive composition (a-4)>
In a reaction vessel equipped with a stirrer, reflux condenser, thermometer, dropping funnel and nitrogen gas inlet, 44.9 parts by mass of butyl acrylate, 50 parts by mass of 2-ethylhexyl acrylate, 2 parts by mass of acrylic acid, 3 parts by mass of vinyl acetate By dissolving 0.1 part by mass of 4-hydroxybutyl acrylate and 0.1 part by mass of 2,2′-azobisisobutylnitrile as a polymerization initiator in 100 parts by mass of ethyl acetate and polymerizing at 70 ° C. for 10 hours. An acrylic copolymer W solution having a weight average molecular weight of 800,000 was obtained.

Next, by adding 30 parts by mass of polymerized rosin ester-based tackifier resin D-135 (manufactured by Arakawa Chemical Co., Ltd.) to 100 parts by mass of acrylic copolymer W, adding ethyl acetate and mixing them, An adhesive composition (a-4) having a nonvolatile content of 45 mass was obtained.

(Preparation Example 5)
<Preparation of adhesive composition (a-5)>
95.5 parts by mass of butyl acrylate, 4 parts by mass of acrylic acid, 0.5 part by mass of hydroxyethyl acrylate, 2 as a polymerization initiator in a reaction vessel equipped with a stirrer, a cold flow cooler, a thermometer, a dropping funnel and a nitrogen gas inlet Acrylic copolymer solution X having a weight average molecular weight of 650,000 was obtained by dissolving 0.2 part of 2,2′-azobisisobutylnitrile in 100 parts by weight of ethyl acetate and polymerizing at 80 ° C. for 8 hours.

Next, 10 parts by mass of rosin ester resin A-100 (manufactured by Arakawa Chemical Co., Ltd.) and 20 parts by mass of polymerized rosin ester resin D-135 (manufactured by Arakawa Chemical Co., Ltd.) with respect to 100 parts by mass of the acrylic copolymer X Then, toluene was added and mixed to obtain an adhesive composition (a-5) having a nonvolatile content of 45% by mass.

(Preparation Example 6)
<Preparation of adhesive composition (a-6)>
Adhesive composition in the same manner as in Preparation Example 1, except that the amount of the terpene phenol-based tackifying resin (softening point 115 ° C., molecular weight 1000) used in Preparation Example 1 was changed from 65 parts by mass to 5 parts by mass. A product (a-6) was obtained.

(Preparation Example 7)
<Preparation of adhesive composition (a-7)>
Epiklone N-680 (a cresol novolac type epoxy resin solution manufactured by DIC Corporation, epoxy equivalent 215 g / eq, non-volatile content 75% by mass) 21.4 parts by mass, “YL-7862” (an epoxy resin manufactured by Mitsubishi Chemical Corporation) The epoxy resin composition Y having a nonvolatile content of 40% by mass was obtained by mixing 48 parts by mass with an epoxy equivalent of 3748 g / eq and a nonvolatile content of 50% by mass, and then mixing 30.6 parts by mass of methyl ethyl ketone.

Next, with respect to 100 parts by mass of the epoxy resin composition Y, 0.4 part by mass of Curazole 2MAOK-PW (manufactured by Shikoku Kasei Co., Ltd., imidazole curing accelerator) is mixed as a curing agent and stirred for 10 minutes. An adhesive composition (a-7) was obtained.

<Preparation of adhesive composition (a-8)>
Adhesive composition in the same manner as in Preparation Example 1 except that the amount of terpene phenol-based tackifier resin used in Preparation Example 1 (softening point 115 ° C., molecular weight 1000) was changed from 65 parts by weight to 20 parts by weight. A product (a-8) was obtained.

<Production of adhesive tape>

Example 1
100 mass of the total solid content of the adhesive composition (a-1) is formed on the surface of a release paper having a thickness of 130 μm having a polyethylene layer on both sides of the fine paper and a silicone-type release treatment agent layer on one side of the polyethylene layer. 10 parts by weight of Matsumoto Microsphere F-36D (manufactured by Matsumoto Yushi Seiyaku Co., Ltd., thermally expandable microcapsules, initial particle size 10-16 μm, expansion start temperature 70-80 ° C.) as a swelling agent for 10 minutes. The agitated material was coated using a rod-shaped metal applicator so that the thickness after drying was 60 μm, and dried for 10 minutes with a drier set at 65 ° C., so that the thermoplastic thermally expandable adhesive layer ( A-1) was produced. The thermoplastic heat-expandable adhesive layer (A-1) is laminated on a release paper different from the above, and a 2 kg hand roller is used to reciprocate the upper surface of the patch, thereby making the thermoplastic heat An adhesive tape comprising an expandable adhesive layer (A-1) was obtained.

(Example 2)
A thermoplastic heat-expandable adhesive layer (A-2) is formed in the same manner as in Example 1 except that the adhesive composition (a-2) is used instead of the adhesive composition (a-1). An adhesive tape was obtained.

(Example 3)
The thermoplastic heat-expandable adhesive layer (A-3) is formed in the same manner as in Example 1 except that the adhesive composition (a-3) is used instead of the adhesive composition (a-1). An adhesive tape was obtained.

Example 4
On the surface of a release paper having a thickness of 130 μm having a polyethylene layer on both sides of a fine paper and a silicone release treatment agent layer on one side of the polyethylene layer, 100 parts by mass of non-volatile content of the adhesive composition (a-4) 10 parts by weight of F-36D as a swelling agent mixed with 10 parts by weight diluted with toluene until 30% by mass was stirred for 10 minutes, and the thickness after drying using a rod-shaped metal applicator was 60 μm In the same manner as in Example 1 except that the thermoplastic thermally expandable adhesive layer (A-4) was produced by drying for 10 minutes with a drier set at 65 ° C. An adhesive tape comprising a thermoplastic thermally expandable adhesive layer (A-4) was obtained.

(Example 5)
A thermoplastic heat-expandable adhesive layer (A-5) was prepared in the same manner as in Example 4 except that the adhesive composition (a-5) was used instead of the adhesive composition (a-4). An adhesive tape was obtained.

(Example 6)
A thermoplastic thermally expandable adhesive layer (A-1) was produced in the same manner as in Example 1.
Next, the adhesive composition (a-1) is applied to the surface of a release paper having a thickness of 130 μm, which has a polyethylene layer on both sides of the fine paper and a silicone-based release treatment agent layer on one side of the polyethylene layer. The adhesive layer (B-1) was prepared by coating with a rod-shaped metal applicator so that the thickness after drying was 60 μm and drying with a dryer set at 65 ° C. for 10 minutes.

By sticking the adhesive layer (B-1) to the thermoplastic heat-expandable adhesive layer (A-1) obtained above and using a 2 kg hand roller, the upper surface of the paste is reciprocated once. Thus, an adhesive tape in which the adhesive layer (B-1) was laminated on one side of the thermoplastic thermally expandable adhesive layer (A-1) was obtained.

(Example 7)
The thermoplastic heat-expandable adhesive layer (A-2) and the adhesive were bonded in the same manner as in Example 6 except that the adhesive composition (a-2) was used instead of the adhesive composition (a-1). An adhesive layer (B-2) was prepared, and an adhesive tape was obtained in which the adhesive layer (B-2) was laminated on one side of the thermoplastic thermally expandable adhesive layer (A-2).

(Example 8)
The thermoplastic thermally expandable adhesive layer (A-3) and the adhesive were bonded in the same manner as in Example 6 except that the adhesive composition (a-3) was used instead of the adhesive composition (a-1). An adhesive layer (B-3) was prepared to obtain an adhesive tape in which the adhesive layer (B-3) was laminated on one side of the thermoplastic thermally expandable adhesive layer (A-3).

Example 9
The thermoplastic thermally expandable adhesive layer (A-4) and the adhesive were bonded in the same manner as in Example 6 except that the adhesive composition (a-4) was used instead of the adhesive composition (a-1). An adhesive layer (B-4) was prepared to obtain an adhesive tape in which the adhesive layer (B-4) was laminated on one side of the thermoplastic thermally expandable adhesive layer (A-4).

(Example 10)
The thermoplastic heat-expandable adhesive layer (A-5) and the adhesive were bonded in the same manner as in Example 6 except that the adhesive composition (a-5) was used instead of the adhesive composition (a-1). An adhesive layer (B-5) was prepared to obtain an adhesive tape in which the adhesive layer (B-5) was laminated on one side of the thermoplastic heat-expandable adhesive layer (A-5).

(Example 11)
After the thermoplastic heat-expandable adhesive layer (A-1) was applied to one side of a polyethylene terephthalate film having a thickness of 12 μm and the adhesive layer (B-1) obtained above was applied to the other side, By pressing and laminating at 4 kgf / cm ² , an adhesive tape was obtained in which a thermoplastic swellable adhesive layer (A-1) and an adhesive layer (B-1) were laminated on a polyethylene terephthalate film.

(Example 12)
Instead of the thermoplastic thermally expandable adhesive layer (A-1), the thermoplastic thermally expandable adhesive layer (A-2) is used instead of the adhesive layer (B-1), and the adhesive layer (B-2). An adhesive tape was obtained by laminating a thermoplastic thermally expandable adhesive layer (A-2) and an adhesive layer (B-2) on a polyethylene terephthalate film in the same manner as in Example 11 except that was used.

(Example 13)
Instead of the thermoplastic heat-expandable adhesive layer (A-1), the thermoplastic heat-expandable adhesive layer (A-3) is used instead of the adhesive layer (B-1), and the adhesive layer (B-3). An adhesive tape was obtained by laminating a thermoplastic thermally expandable adhesive layer (A-3) and an adhesive layer (B-3) on a polyethylene terephthalate film in the same manner as in Example 11 except that was used.

(Example 14)
Instead of the thermoplastic heat-expandable adhesive layer (A-1), a thermoplastic heat-expandable adhesive layer (A-4) is used instead of the adhesive layer (B-1), and an adhesive layer (B-4). An adhesive tape was obtained by laminating a thermoplastic thermally expandable adhesive layer (A-4) and an adhesive layer (B-4) on a polyethylene terephthalate film in the same manner as in Example 11 except that was used.

(Example 15)
Instead of the thermoplastic heat-expandable adhesive layer (A-1), the thermoplastic heat-expandable adhesive layer (A-5) is used instead of the adhesive layer (B-5), and the adhesive layer (B-4). An adhesive tape in which a thermoplastic heat-expandable adhesive layer (A-5) and an adhesive layer (B-5) were laminated on a polyethylene terephthalate film was obtained in the same manner as in Example 15 except that was used.

(Example 16)
The thermoplastic heat-expandable adhesive layer (A-1) was applied to one side of a 35 μm-thick nonwoven fabric, and the adhesive layer (B-1) obtained above was applied to the other side, followed by 80 ° C. By pressing and laminating at 4 kgf / cm ² , an adhesive tape in which the thermoplastic thermally expandable adhesive layer (A-1) and the adhesive layer (B-1) were laminated on the nonwoven fabric was obtained.

(Example 17)
Instead of the thermoplastic thermally expandable adhesive layer (A-1), the thermoplastic thermally expandable adhesive layer (A-2) is used instead of the adhesive layer (B-1), and the adhesive layer (B-2). An adhesive tape in which a thermoplastic thermally expandable adhesive layer (A-2) and an adhesive layer (B-2) were laminated on a nonwoven fabric was obtained in the same manner as in Example 16 except that was used.

(Example 18)
Instead of the thermoplastic heat-expandable adhesive layer (A-1), the thermoplastic heat-expandable adhesive layer (A-3) is used instead of the adhesive layer (B-1), and the adhesive layer (B-3). An adhesive tape in which a thermoplastic thermally expandable adhesive layer (A-3) and an adhesive layer (B-3) were laminated on a nonwoven fabric was obtained in the same manner as in Example 16 except that was used.

(Example 19)
Instead of the thermoplastic heat-expandable adhesive layer (A-1), a thermoplastic heat-expandable adhesive layer (A-4) is used instead of the adhesive layer (B-1), and an adhesive layer (B-4). An adhesive tape in which a thermoplastic heat-expandable adhesive layer (A-4) and an adhesive layer (B-4) were laminated on a nonwoven fabric was obtained in the same manner as in Example 16 except that was used.

(Example 20)
Instead of the thermoplastic heat-expandable adhesive layer (A-1), the thermoplastic heat-expandable adhesive layer (A-5) is used, and instead of the adhesive layer (B-1), the adhesive layer (B-5). An adhesive tape in which a thermoplastic thermally expandable adhesive layer (A-5) and an adhesive layer (B-5) were laminated on a nonwoven fabric was obtained in the same manner as in Example 16 except that was used.

(Example 21)
Expancel 051-40 (manufactured by Nippon Philite Co., Ltd., thermally expandable microcapsule, initial particle size 12 μm, expansion start temperature 110 ° C.) was used as the expanding agent in the same manner as in Example 6, except that F-36D was used. By the method, an adhesive tape in which the adhesive layer (B-1) was laminated on one side of the thermoplastic thermally expandable adhesive layer (A-6) was obtained.

(Example 22)
The thermoplastic heat-expandable adhesive layer (A-7) was prepared in the same manner as in Example 6 except that the adhesive composition (a-6) was used instead of the adhesive composition (a-1). An adhesive tape having an adhesive layer (B-1) laminated on one side was obtained.

(Example 23)
The thermoplastic heat-expandable adhesive layer (A-13) was prepared in the same manner as in Example 6 except that the adhesive composition (a-8) was used instead of the adhesive composition (a-1). An adhesive tape having an adhesive layer (B-1) laminated on one side was obtained.

(Example 24)
Example 6 is the same as Example 6 except that F-30 (manufactured by Matsumoto Yushi Seiyaku Co., Ltd., thermally expandable microcapsules, initial particle size 10 to 16 μm, expansion start temperature 70 to 80 ° C.) was used instead of F-36D. In the same manner, an adhesive tape in which the adhesive layer (B-1) was laminated on one side of the thermoplastic thermally expandable adhesive layer (A-14) was obtained.

(Example 25)
Example except that EXPANSEL 031-40 (manufactured by Nippon Philite Co., Ltd., thermally expandable microcapsule, initial particle size of 10 μm to 16 μm, expansion start temperature of 80 to 95 ° C.) was used instead of F-36D as the expansion agent. 6 was used to obtain an adhesive tape in which the adhesive layer (B-1) was laminated on one side of the thermoplastic thermally expandable adhesive layer (A-15).

(Example 26)
A thermoplastic thermally expandable adhesive layer (in the same manner as in Example 2 except that 5 parts of F-36D was added as an expanding agent to 100 parts by mass of the total solid content of the adhesive composition (a-2). An adhesive tape comprising A-16) was obtained.

(Example 27)
A thermoplastic thermally expandable adhesive layer (in the same manner as in Example 2 except that 15 parts of F-36D was mixed as an expanding agent with respect to 100 parts by mass of the total solid content of the adhesive composition (a-2). An adhesive tape consisting of A-17) was obtained.

(Example 28)
A thermoplastic thermally expandable adhesive layer (in the same manner as in Example 2 except that 30 parts of F-36D was added as an expanding agent to 100 parts by mass of the total solid content of the adhesive composition (a-2). An adhesive tape consisting of A-17) was obtained.

(Comparative Example 1)
An adhesive tape comprising an adhesive layer (A-8) was obtained in the same manner as in Example 1 except that the swelling agent F-36D was not used.

(Comparative Example 2)
An adhesive tape comprising an adhesive layer (A-9) was obtained in the same manner as in Example 2 except that the swelling agent F-36D was not used.

(Comparative Example 3)
An adhesive tape comprising an adhesive layer (A-10) was obtained in the same manner as in Example 3 except that the swelling agent F-36D was not used.

(Comparative Example 4)
An adhesive tape comprising an adhesive layer (A-11) was obtained in the same manner as in Example 4 except that the swelling agent F-36D was not used.

(Comparative Example 5)
An adhesive tape comprising an adhesive layer (A-12) was obtained in the same manner as in Example 5 except that the swelling agent F-36D was not used.

(Comparative Example 6)
On the surface of the release film having one surface of a 75 μm-thick polyethylene terephthalate film peel-treated with a silicone compound, 3 parts of Expandel 051-40 as an expanding agent are added to 100 parts by mass of the adhesive composition (a-7). .2. Mix 2 parts by mass and stir for 10 minutes, apply with a rod-shaped metal applicator so that the thickness after drying is 50 μm, and dry with a dryer set at 75 ° C. for 10 minutes. Thus, an adhesive layer (A-13) was produced. The adhesive layer (A-13) is adhered to the release film, and the adhesive layer (A-13) is adhered by reciprocating the upper surface of the adhesive paste using a 2 kg hand roller. I got a tape.

[Method for Measuring Storage Elastic Modulus of Thermally Expandable Adhesive Layer]
Release the adhesive compositions (a-1) to (a-6) and (a-8) prepared in Preparation Examples 1 to 6 and 8 using an applicator so that the thickness after drying is 100 μm. A plurality of adhesive layers each having a thickness of 100 μm were formed by applying to the surface of the liner and drying at 85 ° C. for 5 minutes.

Next, a test piece composed of an adhesive layer having a thickness of 2 mm was prepared by overlapping the adhesive layers obtained using the same adhesive.

A parallel plate having a diameter of 7.9 mm was attached to a viscoelasticity testing machine (ARES 2kSTD) manufactured by T.A. The test piece is sandwiched between the parallel plates with a compression load of 40 to 60 g, and a storage elastic modulus at 23 ° C. under a condition of a frequency of 1 Hz, a temperature range of −60 to 150 ° C., and a temperature increase rate of 2 ° C./min ( G23) and storage elastic modulus at 70 ° C. (G70) and storage elastic modulus at 120 ° C. (G120) were measured. In addition, since the thermosetting resin was used about the comparative example 6, since the above-mentioned measuring method was not applicable, it omitted.

[Method for measuring initial adhesive strength of thermally expandable adhesive layer]
180 degree peeling adhesion was measured according to JIS Z 0237.
In Examples 6 to 22, the release liner on the adhesive layer (B) side of the adhesive tape was peeled off, and the adhesive layer was lined with a polyethylene terephthalate film having a thickness of 25 μm. For the other, the surface from which the release liner is peeled is not specified. After cutting the backing adhesive tape into a width of 20 mm, the release liner on the thermoplastic thermally expandable adhesive layer (A) side of the adhesive tape is peeled off, and the SUS plate is degreased on the adhesive layer. A test piece was prepared by reciprocating once with a 2 kg roller.
The test piece was allowed to stand for 1 hour in an environment of 23 ° C., and in that environment, a tensilon tensile tester [manufactured by A & D Co., Ltd., model: RTM-100] was used to form a double-sided adhesive tape constituting the test piece. The adhesive strength when peeled from the SUS plate at a speed of 300 mm / min in the direction of 180 degrees was measured.

[Measurement method of expansion coefficient of adhesive tape and each adhesive layer constituting it]
The thickness of the adhesive tape produced by the above method and the thickness of each adhesive layer constituting it were measured using a thickness meter.
The adhesive tape was expanded by leaving it in an environment of 100 ° C. for 30 minutes.
In addition, Example 21 was expanded by leaving it to stand in an environment of 120 ° C. for 30 minutes, and Comparative Example 6 was left in an environment of 130 ° C. for 1 hour.
Next, the thickness of the expanded adhesive tape and the thickness of the adhesive layer constituting the adhesive tape were each measured using a thickness meter.
The expansion rate is the ratio of the adhesive tape after being left to the thickness of the adhesive tape before being left for 30 minutes in an environment of 100 ° C. (before expansion), and the thermoplasticity before being left as it is. The thickness of the thermoplastic heat-expandable adhesive layer (A1) formed by the expansion of the thermoplastic heat-expandable adhesive layer (A) by the standing relative to the thickness of the heat-expandable adhesive layer (A). And the ratio of the thickness of the adhesive layer (B) after the standing to the thickness of the adhesive layer (B) before the standing was calculated according to the following formula.
[Thickness of adhesive tape after being left (after expansion) / Thickness of adhesive tape before being left (before expansion)] × 100
[Thickness of expanded thermoplastic heat-expandable adhesive layer (A) [thermoplastic heat-expandable adhesive layer (A1)] constituting the adhesive tape after leaving (after expansion) / before leaving (before expansion) The thickness of the thermoplastic thermally expandable adhesive layer (A) constituting the adhesive tape]) × 100
[The thickness of the adhesive layer (B) constituting the adhesive tape after being left / the thickness of the adhesive layer (B) constituting the adhesive tape before being left] × 100

[Measurement method of expansion coefficient 2 of adhesive layer (A)]
Except that the adhesive tape was left in an environment of 85 ° C. for 30 minutes, the adhesive layers of Examples 1 to 5 (Examples 1 to 5) The expansion coefficient of A) was measured.

[Evaluation method of void filling property]
Two surface smooth aluminum plates having a width of 15 mm, a length of 70 mm and a thickness of 0.5 mm are degreased, and the end of the upper surface (C1-1) of one aluminum plate (C1) (1 in FIG. 1) In addition, two spacers (3 in FIG. 1) were arranged in parallel with a gap of 12 mm, and adhered using an adhesive tape (50 μm). The spacer used was prepared so that the total thickness of the adhesive tape used for bonding with the spacer was 60 μm thicker than the total thickness of each adhesive tape prepared in Examples 1 to 28 and Comparative Examples 1 to 5. did.
Next, an adhesive tape cut to a size of 10 mm × 10 mm is pasted on the upper surface (C1-1) side of the aluminum plate (C1) and between the two spacers (Examples 6 to 22). The surface corresponding to the thermoplastic heat-expandable adhesive layer (A) was attached, and pressure-bonded using a 2 kg hand roller. The surfaces to which Examples 1 to 5 and Comparative Examples 1 to 6 are attached are not particularly defined.
Next, another aluminum plate (C2) (width 15 mm × length) having a degreased smooth surface on the upper surface of the adhesive tape (the surface corresponding to the adhesive layer (B) in Examples 6 to 25). (70 mm in thickness x 0.5 mm in thickness) were placed and fixed with clips.
The fixed one was heated at 100 ° C. for 30 minutes, and then allowed to stand in a 23 ° C. environment for 30 minutes and cooled. Note that Example 21 was heated at 120 ° C. for 30 minutes, and Comparative Example 6 was heated at 130 ° C. for 1 hour, and then allowed to stand in a 23 ° C. environment for 30 minutes and cooled.
Next, the said clip was removed and the edge part of the aluminum plate (C2) was lifted. At this time, the case where the aluminum plate (C1) did not fall was evaluated as “◯”, and the case where it dropped was evaluated as “x”.

[Measurement method of shear adhesive strength 1]
A sample similar to the void filling evaluation was prepared, heated at 100 ° C. for 30 minutes, allowed to stand in a 23 ° C. environment for 30 minutes and cooled, and then the clip was removed as a test piece. Note that Example 21 was heated at 120 ° C. for 30 minutes, and Comparative Example 6 was heated at 130 ° C. for 1 hour, then allowed to cool for 30 minutes in a 23 ° C. environment, and then the clip was removed.
The adhesive strength of the adhesive tape was determined by chucking the end portions of the two aluminum plates of the test piece and performing a tensile test in a 180 degree direction at a tensile speed of 10 mm / min using a tensile tester. .

[Measurement method of shear adhesive strength 2]
The spacer used was prepared so that the total thickness of the adhesive tape used for bonding to the spacer was 120 μm thicker than the total thickness of each adhesive tape prepared in Examples 1-28 and Comparative Examples 1-5. Except for the above, the measurement was performed by the same method as the method for measuring the shear adhesive strength 1.

[Measurement method of shear adhesive strength 3]
Test specimens similar to those for evaluation of void filling properties were prepared using Examples 1 to 5, heated at 85 ° C. for 30 minutes, allowed to cool in an environment of 23 ° C. for 30 minutes, and then removed from the clip. It was a piece. Further, the spacer is prepared so that the total thickness of the spacer and the adhesive tape used for bonding is 30 μm thick with respect to the total thickness of each of the adhesive tapes prepared in Examples 1 to 5, and the shear adhesive force 1 is measured. Measurement was carried out in the same manner as above.

[Measurement method of shear adhesive strength 4]
Adhesive layer of adhesive tape cut into a size of 10 mm × 10 mm on the upper surface (C1-1) side of the aluminum plate (C1) and between the two spacers using Examples 6 to 10 The measurement was carried out by the same method as that for measuring the shear adhesive strength 1 except that (B) was applied.

[Component selectivity]
Test specimens similar to those for the void filling evaluation were prepared using an aluminum plate and an acrylic plate using the adhesive tapes prepared in Examples 1 to 28 and Comparative Examples 1 to 6, respectively. (Acrylic plate: two surface-smooth acrylic plates having a width of 15 mm, a length of 70 mm, and a thickness of 1.5 mm were degreased, and the upper surface (D1-1) of one acrylic plate (D1) (1 in FIG. 2) 2 spacers (3 in FIG. 2) were arranged in parallel with a gap of 12 mm, and were bonded using an adhesive tape (50 μm), which was bonded to the spacer and used for bonding. A tape prepared so that the total thickness of the tape was 60 μm thick with respect to the total thickness of each adhesive tape prepared in Examples 1 to 28 and Comparative Examples 1 to 5 was used.
Next, an adhesive tape cut to a size of 10 mm × 10 mm is pasted on the upper surface (D1-1) side of the acrylic plate (D1) and between the two spacers (Examples 6 to 22). The surface corresponding to the thermoplastic heat-expandable adhesive layer (A) was attached, and pressure-bonded using a 2 kg hand roller. Next, on the upper surface of the adhesive tape (the surface corresponding to the adhesive layer (B) in Examples 6 to 22), another acrylic plate (D2) (width 15 mm × long 70 mm × 1.5 mm in thickness) were placed and fixed with clips. )
The test piece was heated at 100 ° C. for 30 minutes, then allowed to stand in a 23 ° C. environment for 30 minutes and cooled. In addition, about Example 22, after heating at 130 degreeC for 30 minutes, it was left to stand in a 23 degreeC environment for 30 minutes, and was cooled. Next, the clip was removed, and the ends of the aluminum plate (C2) and the acrylic plate (C2) were lifted. At this time, when the aluminum plate (C1) and the acrylic plate (D1) did not fall and the aluminum plate and the acrylic plate were not deformed, “◯”, but the aluminum plate and the acrylic plate did not fall but were deformed In the case where the mark was seen, “△” was evaluated, and in the case of falling, “X” was evaluated.

* F-36D: Matsumoto Microsphere F-36D
* F-30: Matsumoto Microsphere F-30
* 051-40: Expandance 051-40
* 031-40: Expandance 031-40

1 Aluminum plate (C1)
2 Aluminum plate (C2)
3 Spacer 4 Adhesive tape 5 Gap between adhesive tape and aluminum plate (c2)

Claims (11)

1. An adhesive tape for use in filling a void of the adherend (C1) or a gap between the adherend (C1) and the adherend (C2), the adhesive tape being a thermoplastic heat It has an expandable adhesive layer (A), and the expansion coefficient in the thickness direction of the thermoplastic heat-expandable adhesive layer (A) [the thickness of the thermoplastic heat-expandable adhesive layer (A1) after heating] Thickness / thickness of thermoplastic heat-expandable adhesive layer (A) before heating] × 100 is 150% or more.
2. It has an adhesive layer (B) on at least one surface side of the thermoplastic thermally expandable adhesive layer (A), and an expansion coefficient in the thickness direction of the adhesive layer (B) [adhesive layer after heating The adhesive tape according to claim 1, wherein (B1) thickness / thickness of adhesive layer (B) before heating] × 100 is 120% or less.
3. Before the thermoplastic thermally expandable adhesive layer (A) is heated to form the thermoplastic thermally expandable adhesive layer (A1), the adhesive layer is affixed to the adherend (C1). The adhesive tape according to claim 2.
4. The adhesive tape according to any one of claims 1 to 3, wherein the thermoplastic thermally expandable adhesive layer (A) has an adhesive force of 0.5 N / 20 mm or more.
5. The thermoplastic thermoplastic expandable adhesive layer (A) is a layer containing a thermoplastic resin and a thermally expanded capsule having an expansion start temperature in the range of 50 ° C to 150 ° C. The adhesive tape as described in the item.
6. The storage elastic modulus of the thermoplastic resin measured by a dynamic viscoelastic spectrum at 1 Hz in a range of 70 ° C to 120 ° C is in a range of 1.0 × 10 ² Pa to 1.0 × 10 ⁷ Pa. 5. The adhesive tape according to 5.
7. The expanded product of the adhesive tape according to any one of Claims 1 to 6, wherein the gap of the adherend (C1) or the gap between the adherend (C1) and the adherend (C2) is Articles glued or filled through.
8. The thermoplastic heat-expandable adhesive layer (A) or the adhesive layer (B) of the adhesive tape according to any one of claims 1 to 6 is formed on a part (c1-1) constituting the adherend (C1). ), The step [2] of heating the thermoplastic heat-expandable adhesive layer (A) at a temperature of 50 ° C. to 150 ° C., and the thermoplastic heat-expandable adhesive layer ( A) is expanded to form a thermoplastic thermally expandable adhesive layer (A1) [3], and the thermoplastic thermally expandable adhesive layer (A1) or the adhesive layer ( B) has a step [4] applied to another part (c1-2) or another adherend (C2) constituting the adherend (C1). The gap of (C1) or the gap between the adherend (C1) and the adherend (C2) is any one of claims 1 to 6. Method for producing a bonded or filled article through expansion of the adhesive tape according to item.
9. The thermoplastic heat-expandable adhesive layer (A) of the adhesive tape according to any one of claims 1 to 6, wherein the step [1] is applied to a site (c1-1) constituting the adherend (C1). The method for producing an article according to claim 8, comprising a step of pressure-bonding the substrate with a force of 0.1 N / cm ² or more.
10. The step [4] is caused by the force generated by expanding the thermoplastic thermally expandable adhesive layer (A), and the thermoplastic thermally expandable adhesive layer (A1) or the adhesive layer (B), The method for producing an article according to claim 8 or 9, comprising a step of pressure-bonding the other part (c1-2) or the other adherend (C2) constituting the adherend (C1).
11. The step of applying the thermoplastic heat-expandable adhesive layer (A) of the adhesive tape according to any one of claims 1 to 6 to the site (c1-1) constituting the adherend (C1) [1 ], The step [2] of heating the thermoplastic thermally expandable adhesive layer (A), the thermoplastic thermally expandable adhesive layer (A) is expanded by the heating, and the thermoplastic thermally expandable adhesive layer ( Step [3] in which A1) is formed, and the thermoplastic thermally expandable adhesive layer (A1) or adhesive layer (B) constituting the adhesive tape constitutes the adherend (C1). The voids of the adherend (C1), or the adherend (C1), characterized in that it has the step [4] applied to the part (c1-2) or other adherend (C2) And filling the gap between the adherend (C2).

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