JPWO2019131167A1 - Method for manufacturing article using adhesive tape - Google Patents

Abstract

The problem to be solved by the present invention is to provide a method for manufacturing an article, which prevents wrinkles and gaps from occurring and secures high waterproofness when an adhesive tape is attached to members having various shapes such as a flat surface, a curved surface and a 3D shape. Is to provide. According to the present invention, the end portions of two or more adhesive tapes having an expandable adhesive layer (A) are arranged close to each other, and one surface side of the adhesive tapes constitutes an adherend (C1). Step [1] of sticking to (c1-1), Step [2] of sticking the other surface side of the adhesive tape to another adherend (C2), to the expandable adhesive layer (A) An adhesive tape comprising a step [3] of giving a stimulus and a step [4] of forming the expandable adhesive layer (A1) by expanding the expandable adhesive layer (A) by the stimulus. The present invention relates to a method for manufacturing an article adhered via an expanded material.

Description

TECHNICAL FIELD The present invention relates to a method of manufacturing an article that can be used in various manufacturing scenes of an article including an electronic device.

Generally, 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, for example, for automobile members and electric devices. Widely used in the production of various products. For example, in electronic devices, in mobile electronic devices such as smartphones, mobile phones, PHS, digital cameras, music players, electronic books, and notebook personal computers, the display panel, which is the information display unit, and the housing are bonded together. Adhesive tape is used to fix various members and modules. When joining the display panel and the housing, the adhesive tape is cut into a window frame shape along the peripheral edge of the display panel, and the window frame-shaped adhesive tape is attached to the peripheral edge of the display panel or the housing. After that, the display panel and the casing are fixed together. As the adhesive tape used at this time, both sides of the foam base material are adhered to the joint surface of the casing, the waterproof property between the display panel and the casing is ensured, and the impact is absorbed when dropped. A double-sided pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer is used (Patent Document 1).
On the other hand, in recent years, automobile parts, electronic devices, and the like have increased in curved surface and 3D shape, and it is difficult or difficult to apply the adhesive tape cut into the window frame shape to a curved surface or 3D shaped member. At this time, wrinkles and gaps may occur, which makes it difficult to ensure the above performance.

JP, 2009-108314, A

The problem to be solved by the present invention is to provide a method for manufacturing an article, which prevents wrinkles and gaps from occurring and secures high waterproofness when an adhesive tape is attached to members of various shapes such as a flat surface, a curved surface and a 3D shape. Is to provide.

The present invention is a method for producing an article having a structure in which an adhesive tape is attached to an adherend, in which two or more adhesive tapes having an expandable adhesive layer (A) are arranged with their end portions being close to each other. Then, the step [1] of attaching one surface side of the adhesive tape to the part (c1-1) constituting the adherend (C1), the other surface side of the adhesive tape to the other adherend ( C2) is applied to [2], the intumescent adhesive layer (A) is stimulated [3], the intumescent adhesive layer (A) is inflated by the stimulus, and the intumescent adhesive layer (A) is expanded. The present invention relates to a method for producing an article, which comprises the step [4] of forming A1).

According to the method for producing an article of the present invention, it is possible to prevent wrinkles and gaps from occurring when a pressure-sensitive adhesive tape is attached to members having various shapes such as a flat surface, a curved surface, and a 3D shape, thereby ensuring high waterproofness.

In process [1] of this invention, it is sectional drawing arrange|positioned so that the edge part of two adhesive tapes (A and B) which have an expandable adhesive layer (A) may contact an adherend. In process [1] of this invention, it is sectional drawing which arrange|positioned the edge part of two adhesive tapes (A and B) which have an expandable adhesive agent layer (A) in an adherend by overlapping. It is the figure which looked at the above-mentioned Drawing 1 and Drawing 2 from the upper part. FIG. 3 is a cross-sectional view of an article according to the manufacturing method of the present invention in Example 1 before expansion. FIG. 8 is a cross-sectional view of an article according to a manufacturing method of the present invention in Example 4 before expansion.

The method for producing an article of the present invention is a method for producing an article having a structure in which an adhesive tape is attached to an adherend, and the end portions of two or more adhesive tapes having an expansive adhesive layer (A) [1], the other side of the adhesive tape is attached to the part (c1-1) that constitutes the adherend (C1), and the other side of the adhesive tape is attached to the other side. [2] attached to the adherend (C2), step [3] of applying a stimulus to the expandable adhesive layer (A), the expandable adhesive layer (A) is expanded by the stimulation, The method is characterized by passing through the step [4] of forming the expansion adhesive layer (A1).

The step [1] is a step of attaching an adhesive tape to an adherend. Specifically, in the step [1], the ends of two or more adhesive tapes having an expansive adhesive layer (A) are placed so as to overlap or be close to each other, and one surface of the adhesive tape It is a step of attaching the side to the site (c1-1) constituting the adherend (C1).

The ends of two or more adhesive tapes having the expandable adhesive layer (A) in the step [1] are arranged close to each other, and one surface side of the adhesive tapes constitutes the adherend (C1). In the step of sticking to the site (c1-1), when two or more of the adhesive tapes are arranged such that their ends are close to each other, it is preferable that there is no gap, but the gap between the ends is 100 μm or less. Preferably, it is preferably 75 μm or less, and preferably 50 μm or less when the expansive adhesive layer (A) is expanded in the step [4] to form the expansive adhesive layer (A1). It is more preferable that the gap between the ends of the adhesive tape can be filled and fixed.

The surface of the adhesive tape to be adhered to the adherend in the step [1] is not particularly specified, but for example, the expandable adhesive layer (A) is provided on one surface side and the adhesive layer described below is attached to the other surface. When the adhesive tape having the agent layer (B) is used, applying the adhesive layer (A) to the adherend in the step [1] is performed by applying the other surface side of the adhesive tape to another adherend. It is preferable because it adheres more firmly to the body (C2).

In the step [1], it is preferable that one side of the adhesive tape is pressure-bonded to the portion (c1-1) constituting the adherend (C1) with a load of 0.1 N/cm ² or more, and 0.5 N. more preferably to crimp at / cm ² or more loads, adhesion be crimped with 1N / cm ² or more load, to the site (c1-1) constituting the adherend (C1) of the adhesive tape Is increased, and the deviation between the adhesive tape and the adherend (C1) can be suppressed, which is preferable.

When pressing one surface side of the adhesive tape to the part (c1-1) forming the adherend (C1), a device such as a press machine or a roller may be used as necessary, You may press them with your finger.

In the step [2], the other surface side of the adhesive tape attached to the part (c1-1) constituting the adherend (C1) in the step [1] is attached to another adherend (C2). ) Is attached. When the other surface side of the adhesive tape is attached to another adherend (C2), a load is applied to the interface between the adherend (C2) and the adhesive tape via the adherend (C2). It may be applied or optionally pressure-bonded.

The step [3] is a step of stimulating the expandable adhesive layer (A). Examples of the stimulus include heat and light. It is preferable to apply heat as the stimulus because it can be applied to a member that does not transmit light. The heating temperature is preferably 60° C. to 145° C., and the temperature of 70° C. to 140° C. is excellent in storage stability and does not damage the adherend having low heat resistance. It is preferable because the adhesive tape can be sufficiently expanded and excellent adhesive force can be obtained after expansion.
Examples of the heating method include a method in which an article is placed in a heating device such as an oven or a heating furnace to heat the entire article, or a heat source for the expandable adhesive layer (A), the adhesive tape, or the adherend. There is a method of heating the expandable adhesive layer (A) by bringing them into contact with or approaching each other.
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 according to the size of the article.

The step [4] is a step in which the expandable adhesive layer (A) forms the expandable adhesive layer (A1).

In the step [3] and the step [4], in the process of stimulating the adhesive tape to expand the expansive adhesive layer (A) to form the expansive adhesive layer (A1), it is preferable to 50 N / cm ² or less of a load is applied, it is preferable to 25 N / cm ² or less of a load is applied, be 10 N / cm ² or less of a load is applied, the expandable adhesive layer This is preferable because it is possible to preferably fill the gap generated when the ends of two or more adhesive tapes having (A) are brought close to each other.

As a method for manufacturing the article, the steps [1], [2], [3] and [4] may be performed in this order before stimulating and forming the expansion adhesive layer (A1). It is preferable because it has excellent adhesive strength, can be expanded by stimulation, and exhibits excellent adhesive strength even after expansion. In particular, when the surface of the adherend (C1) or (C2) is rough, it is effective in expressing a good adhesive force.

In the present invention, the adhesive layer (A1) or the adhesive layer (B) and the adherend (C1) are configured by a force generated by expanding the expandable adhesive layer (A). Part (c1-2) or other adherend (C2) is pressure-bonded. Therefore, for example, when the adherend (C1) has a gap or when there is a gap between the adherend (C1) and the adherend (C2), for example, a press machine or the like is used. No need to apply pressure. Further, 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 can be used even when an adherend having an uneven surface (having a rough surface) is used. A gap is less likely to be formed between the substrate and the adherend.
Examples of the adherends (C1) and (C2) include glass, metals such as aluminum, plastics made of resin such as acryl and polycarbonate, and the like. The adherends (C1) and (C2) may be made of the same material or shape, or may be made of different materials or shapes.
As the adherends (C1) and (C2), the surfaces in contact with the expandable adhesive layer (A) and the adhesive layer (B) may be rough surfaces.

The shapes of the adherend (C1) and the adherend (C2) are not particularly specified, but examples thereof include a two-dimensional shape, a three-dimensional shape (curved surface or the like), a shape having surface irregularities, a fitting shape, and the like. To be A combination of the above shapes may be used.

As the adherend, for example, minute irregularities of 1 μm or less on the surface of the adherend, irregularities of 1 μm or more such as embossing or printing step, and the adherend itself may have warp or distortion. The unevenness is preferably 500 μm or less, more preferably 400 μm or less, further preferably 300 μm or less, and the warp or strain of the adherend is relative to the portion where the adhesive tape is adhered to the adherend. The difference between the highest point and the lowest point is preferably 500 μm or less, more preferably 400 μm or less, and 300 μm or less means that there is a void when the ends of the adhesive tape are arranged close to each other. Or the adherend (C1) has a void, or there is a gap between the adherend (C1) and the adherend (C2), and the height (thickness) of the void is It is more preferable that the adhesive tape is sufficiently adhered when the adhesive tape is expanded by being stimulated even when it is large.
Further, the adherend may be a combination of curved surfaces, and the curved surfaces may have the same radius of curvature or different curvature radii. The radius of curvature is in the range of 0.1 mm to 10 m, and the adhesive tape was expanded while applying a load of 50 N/cm ² or less to the adhesive tape via one or both adherends in contact with the adhesive tape. Sometimes good adhesion can be obtained. When the radii of curvature of the adherends are different from each other, the gap of the adherend to which the adhesive tape is attached from the surface of the adhesive tape to the other adherend is preferably 500 μm or less, and 400 μm or less It is more preferable that the adhesive tape has a gap of 300 μm or less when the ends of the adhesive tape are arranged close to each other, or the adherend (C1) has a gap, or Even when there is a gap between the adherend (C1) and the adherend (C2) and the height (thickness) of the gap is large, the adhesive tape was stimulated and expanded. It is more preferable because it can sometimes adhere sufficiently.

The adhesive tape used in the present invention can be expanded by applying heat to the thermoplastic heat-expandable adhesive layer (A) or the entire adhesive tape.
The adhesive tape used in the present invention has an expansive adhesive layer (A) that expands by stimulation, but the expansive adhesive layer (A) may be one kind or two or more kinds, and a single layer or two layers. It may be more than. Further, the adhesive tape may be composed of only the expansive adhesive layer (A), and the expansive adhesive layer (A) and an adhesive layer which is difficult to expand (for example, an adhesive layer (to be described later) ( B) or the like), but the adhesive tape composed of the expandable adhesive layer (A) and the adhesive layer which is difficult to expand has a void in the adherend (C1), or It is preferable to fill the space between the adherend (C1) and the adherend (C2) with the expanded material of the adhesive tape and firmly bond them.

As the adhesive tape composed of the expandable adhesive layer (A) and the adhesive layer that does not expand easily, specifically, the adhesive tape described below is bonded to at least one surface of the expandable adhesive layer (A). It is preferable to use the one having the agent layer (B). As the adhesive tape, it is excellent that the expandable adhesive layer (A) is attached to the adherend in advance before the expansion, which is excellent between the expanded adhesive layer (A1) after the expansion and the adherend. It is preferable for maintaining good adhesion.

(Expandable adhesive layer (A))
The expandable adhesive layer (A) is a layer that can be expanded by a stimulus. The stimulus includes heat and/or light, with heat being preferred. As the expansive adhesive layer (A), the expansion coefficient in the thickness direction of the expansive adhesive layer (A) [the thickness of the expansive adhesive layer (A) after the heating/after the standing/before the standing The thickness of the expandable adhesive layer (A)]×100 is preferably 120% or more. The expansion rate is preferably 150% or more, and more preferably 200% to 1000%. With such an adhesive tape, when the end portions of the adhesive tape are arranged close to each other, there is a void, the adherend (C1) has a void, or the adherend (C1) ) And the adherend (C2) have a void, and the height (thickness) of the void is large, by expanding the adhesive tape, the other adherent is adhered in the void. The body can be suitably fixed or the space 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.
In addition, the said expansion rate WHEREIN: When leaving the said adhesive tape at the temperature of 50 degreeC-150 degreeC for 30 minutes, the said leaving|leaving with respect to the thickness of the expansive adhesive layer (A) before the said leaving (before expansion) Refers to the ratio of the thickness of the expanded adhesive layer (A1) formed by expanding the expandable adhesive layer (A), preferably under a temperature of 60°C to 145°C, and a temperature of 70°C to 140°C. Lower is more preferable.

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

The thickness of the expandable adhesive layer (A) before expansion is preferably in the range of 10 μm to 300 μm, more preferably in the range of 20 μm to 250 μm, and in the range of 30 μm to 200 μm, There is a void when the ends of the adhesive tape are arranged close to each other, the adherend (C1) has a void, or the adherend (C1) and the adherend (C2). Even if there is a gap between the gap and the height (thickness) of the gap, the other adherend is preferably fixed in the gap by expanding the adhesive tape. It is preferable that the inside of the void can be filled with the adhesive tape.

On the other hand, the thickness of the expandable adhesive layer (A1) formed by expanding the expandable adhesive layer (A) is preferably in the range of 20 μm to 3000 μm, and in the range of 40 μm to 2500 μm. However, it is preferable to obtain a more excellent adhesive force. Moreover, it is preferable that the expansion adhesive layer (A1) has a porous structure.

Further, as the adhesive tape, it is preferable to use one in which the thickness of the expandable adhesive layer (A) is 10% or more with respect to the total thickness of the adhesive tape, and 30% or more. It is more preferable to use one because it is easy to suitably fix the other adherend in the void and to fill the void with the adhesive tape.
As described above, the expansive adhesive layer (A) has an adhesive strength sufficient for adhering to an adherend in advance, and is adhered by a pressing force generated by the expansion of the expansive adhesive layer (A). A material that can fill and adhere to the voids of the body (C1) or the voids between the adherend (C1) and the adherend (C2) is used.

The expandable adhesive layer (A) can be produced, for example, by coating the adhesive composition (a) described below on a support such as a release liner or a pressure-sensitive adhesive tape, followed by drying.

The expandable adhesive layer (A) can be formed using, for example, 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 further preferably 90% by mass or more with respect to the total solid components of the adhesive composition (a).

As the thermoplastic resin, one that can be easily expanded by heating can be used.
As the thermoplastic resin, one having a storage elastic modulus G23 measured by a dynamic viscoelastic spectrum at 1 Hz and 23° C. of 1.0×10 ^{3 to} 5.0×10 ⁷ Pa is used. And a storage elastic modulus G70 measured by a dynamic viscoelastic spectrum at 1 Hz and 70° C. of 1.0×10 ^{2 to} 1.0×10 ⁷ Pa is preferably used. Before heating, the storage elastic modulus G120 measured by the dynamic viscoelastic spectrum at 1 Hz and 120° C. is in the range of 1.0×10 ^{2 to} 1.0×10 ⁶ Pa before heating. Even so, it is particularly preferable in order to obtain an adhesive tape which can prevent the adhesive tape from peeling off from the adherend or be displaced, and can be expanded to a level capable of sufficiently filling the voids.

The adhesive tape in a state before the thermoplastic heat-expandable adhesive layer (A) is expanded can prevent the adhesive tape from being peeled or displaced from the adherend even before heating, and can be kept at room temperature after expansion. The storage elastic modulus G23 measured by a dynamic viscoelastic spectrum at 1 Hz and 23° C. is preferably 1.0×10 ^{3 to} 5.0×10 ⁷ Pa, and more preferably, in order to suppress shrinkage and the like under the environment. It is possible to use one 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 has a storage elastic modulus G23 measured by a dynamic viscoelastic spectrum at 1 Hz and 23° C. within the above range, and has a dynamic viscosity at 1 Hz in the range of 70° C. to 120° C. It is preferable to use one having a storage elastic modulus measured by an elasticity 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 in suppressing expansion and expanding in the thickness direction.
As the thermoplastic resin, the storage elastic modulus G70 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.
As the thermoplastic resin, the storage elastic modulus G70 measured by a dynamic viscoelastic spectrum at 1 Hz and 70° C. is preferably 1.0×10 ^{2 to} 1.0×10 ⁷ Pa, and more preferably 5 It is possible to use one having a viscosity of 0.0×10 ^{2 to} 5.0×10 ⁶ Pa, particularly preferably 5.0×10 ^{2 to} 1.0×10 ⁶ Pa.

The storage elastic modulus G120 of the thermoplastic resin measured by a dynamic viscoelastic spectrum at 1 Hz and 120° C. is preferably 1.0×10 ^{2 to} 1.0×10 ⁶ Pa. It is more preferably 0×10 ^{2 to} 5.0×10 ⁶ Pa, further preferably 5.0×10 ^{2 to} 2.0×10 ⁵ Pa.

The storage elastic modulus G120 of the thermoplastic resin is preferably smaller than the storage elastic modulus G70, and the storage elastic modulus G70 is preferably smaller than the storage elastic modulus G23.

The storage elastic modulus G23, G70, and G120 were measured using a commercially available viscoelasticity tester by the method described in Examples below. The test piece for the measurement was obtained by heating the thermoplastic resin (without expanding agent) contained in the thermoplastic thermally expandable adhesive layer (A), applying it on a release liner, and cooling it. A test piece with a thickness of 2 mm is used.

The thermoplastic resin has, for example, an excellent adhesive force before expansion, is softened at the expansion start temperature of the expander, and the expander easily expands, and can exhibit excellent adhesive force 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), vinyl chloride such as vinyl chloride-vinyl acetate copolymer resin. Acrylic resins such as polyacrylic acid, polymethacrylic acid, polymethyl acrylate, polymethyl methacrylate (PMMA), polyethyl methacrylate, etc.; polyethylene terephthalate (PET), polybutylene terephthalate, Polyester resin such as polytrimethylene terephthalate, polyethylene naphthalate, polybutylene naphthalate; polyamide resin such as nylon (registered trademark); polystyrene (PS), imide-modified polystyrene, acrylonitrile butadiene Styrene (ABS) resin, imide-modified ABS resin, styrene-acrylonitrile copolymerization (SAN) resin, polystyrene-based resin such as acrylonitrile-ethylene-propylene-diene-styrene (AES) resin, polyethylene (PE) resin, polypropylene (PP) Resin, olefin resin such as cycloolefin resin; cellulose resin such as nitrocellulose and cellulose acetate; silicone resin; thermoplastic resin such as fluorine resin, styrene thermoplastic elastomer, olefin thermoplastic elastomer, vinyl chloride resin Examples thereof include thermoplastic elastomers, urethane-based thermoplastic elastomers, ester-based thermoplastic elastomers, amide-based thermoplastic elastomers, and the like.
Among these, as the thermoplastic resin, among these, styrene-based thermoplastic elastomer, olefin-based thermoplastic elastomer, vinyl chloride-based thermoplastic elastomer, ester-based thermoplastic elastomer, urethane-based thermoplastic elastomer, amide-based thermoplastic elastomer, or acryl It is preferable to use a system resin and the like, and it is particularly preferable to use a styrene thermoplastic elastomer or an acrylic resin.

Examples of the styrene-based thermoplastic elastomer include styrene-AB diblock copolymers such as styrene-ethylene-butylene copolymer (SEB); styrene-butadiene-styrene copolymer (SBS), hydrogenated products of SBS. (Styrene-ethylene-butylene-styrene copolymer (SEBS)), styrene-isoprene-styrene copolymer (SIS), hydrogenated product of SIS (styrene-ethylene-propylene-styrene copolymer (SEPS)), styrene -Styrene-based ABA type triblock copolymers such as isobutylene-styrene copolymer (SIBS); Styrene-based ABAB type tetrablock copolymers such as styrene-butadiene-styrene-butadiene (SBSB); Styrene-butadiene-styrene- A styrene-based ABABA type pentablock copolymer such as butadiene-styrene (SBSBS); a styrene-based multiblock copolymer having the above AB repeating units; a styrene-based random copolymer such as styrene-butadiene rubber (SBR) Hydrogenated products obtained by hydrogenating ethylenic double bonds; and the like. A commercial item may be used for the styrene-based thermoplastic elastomer.

As the acrylic resin, for example, a resin obtained by polymerizing a monomer containing an alkyl(meth)acrylate can be used.
As the alkyl (meth)acrylate, it is preferable to use a (meth)acrylate having an alkyl group having 4 to 12 carbon atoms, and specifically, butyl (meth)acrylate, isooctyl (meth)acrylate, 2- It is preferable to use ethylhexyl (meth)acrylate or the like, and it is more preferable to use butyl acrylate and 2-ethylhexyl acrylate alone or in combination.
In addition to the above-mentioned monomers, acrylonitrile, (meth)acrylic acid, maleic anhydride, acrylamide, itaconic acid, styrene, vinyl acetate and the like can be used as the monomer.

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

As the thermosetting resin, urethane resin, phenol resin, unsaturated polyester resin, epoxy resin, acrylic resin or the like can be used. Among them, for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, hindertoin type epoxy resin, biphenyl type epoxy resin, alicyclic epoxy resin, triphenylmethane type epoxy resin, phenol novolac type epoxy resin , Cresol novolac type epoxy resin, naphthol novolac type epoxy resin, dicyclopentadiene/phenol epoxy resin, alicyclic amine epoxy resin, aliphatic amine epoxy resin, and CTBN modified (carboxy terminated butadiene nitrile modified) or halogen modified These epoxy resins and the like can be used alone or in combination of two or more.

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 thermal expansion adhesive layer (A1) after expansion, such as ammonium carbonate, ammonium hydrogen carbonate, ammonium nitrite, ammonium borohydride, and azide. Inorganic compounds such as trichloromonofluoromethane, azo compounds such as azobisisobutyronitrile, hydrazine compounds such as paratoluenesulfonyl hydrazide, semicarbazide compounds such as p-toluenesulfonyl semicarbazide, 5-morpholyl-1 A triazole compound such as 2,2,3,4-thiatriazole and an N-nitroso compound such as N,N′-dinitrosoterephthalamide can be used.

The expansion agent is preferably a heat expansion agent that expands by heat, and for example, an expansion capsule such as a heat expansion capsule in which a hydrocarbon solvent is microencapsulated can be used. As the thermal expansion agent, it is preferable to use one that can generate a gas and expand at a temperature around the softening point of the thermoplastic resin or the thermosetting 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 storage stability and heat resistance. It is preferable because the adhesive tape can be sufficiently expanded without damaging the adherend having a low heat resistance and an excellent adhesive force can be obtained after the expansion.
As the expansion agent, it is preferable to use a heat-expandable capsule in which a hydrocarbon solvent is microencapsulated, in order to prevent deterioration of the expandable adhesive layer (A) due to the influence of heat or the like. Is more preferable. The swelling agent may be used alone or in combination of two or more.

Examples of commercially available heat-expandable capsules include Expancel (manufactured by Nippon Philite Co., Ltd.), Matsumoto Microsphere (manufactured by Matsumoto Yushi-Seiyaku Co., Ltd.), Microsphere (manufactured by Kureha Co., Ltd.) and the like.
As the heat-expandable capsule, Matsumoto Yushi-Seiyaku Co., Ltd. Matsumoto Microsphere F-30, F-36, F-36D, F-36LV, F-48, F-48D, F-50, FN-80GS, Since F-65, Explancel 053-40, 007-40, 031-40 manufactured by Nippon Philite Co., Ltd. expands before and after the temperature at which the thermoplastic resin softens, the plane direction of the adhesive tape (flow direction). It is preferable because expansion in the thickness direction can be suppressed and expansion in the thickness direction can be more effectively expanded.
As the thermally expandable capsule, it is preferable to use one having a volume (volume expansion coefficient) after expansion of 8 to 60 times as large as the volume of the capsule before expansion.

The amount of the expansion agent used, preferably the amount of the heat-expandable capsules, is in the range of 0.3 parts by mass to 30 parts by mass with respect to 100 parts by mass of the solid content of all the components of the layer (A). It is preferable that it is in the range of 1 part by mass to 20 parts by mass, more preferably in the range of 3 to 17 parts by mass, and further preferably in the range of 5 parts by mass to 15 parts by mass. It is more preferable because it can be sufficiently expanded to fill the voids possessed by, and more excellent adhesive force can be obtained.

As the adhesive composition (a), in addition to the above-mentioned ones, those containing a tackifier, a cross-linking agent, a curing agent, a curing accelerator and the like can be used if necessary.

(Adhesive layer (B))
Further, as the adhesive tape used in the present invention, as described above, it is preferable to use one having the adhesive layer (B).
The adhesive layer (B) constituting the adhesive tape can be formed using an adhesive composition (b) capable of forming a layer having tackiness or adhesiveness.

As the adhesive layer (B), the expansion coefficient in the thickness direction of the adhesive layer (B) [the thickness of the adhesive layer (B) after heating/the adhesive layer before standing (( Thickness of B)]×100 of 120% or less can be used. The expansion coefficient of the adhesive layer (B) is preferably 115% or less, and more preferably 110% or less. With such an adhesive tape, it is possible to maintain an excellent adhesive force to an adherend even after the expandable adhesive layer (A) has expanded. In addition, the expansion coefficient of the adhesive layer (B) is as follows, when the adhesive tape is left in an environment of 100° C. for 30 minutes, with respect to the thickness of the adhesive layer (B) before the leaving. 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 300 μm, and in the range of 5 μm to 200 μm, the expansive adhesive layer (A) constituting the adhesive tape expands. , The voids of the adherend (C1) or the gap between the adherend (C1) and the adherend (C2) are filled, and the adhesive layer (B) becomes the adherend (C2). It is more preferable because it can exhibit an excellent adhesive force when attached.

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

As the adhesive composition (b), it is possible to use, for example, a resin containing a resin such as the thermoplastic resin and, if necessary, a tackifying resin, a cross-linking agent, and other additives.

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

As the cross-linking agent, known isocyanate-based cross-linking agents, epoxy-based cross-linking agents, aziridine-based cross-linking agents, polyvalent metal salt-based cross-linking agents, and metal chelates for the purpose of improving the cohesive force 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)epoxysilane cross-linking agent, or the like can be used.

As the additive, a base (such as aqueous ammonia) or acid for adjusting the pH, a foaming agent, a plasticizer, a softening agent, an antioxidant, if necessary, within a range that does not impair the desired effect of the present invention, Glass or plastic fibrous, balloon-shaped, bead-shaped, metal powder-shaped fillers, colorants such as pigments and dyes, pH adjusters, film-forming aids, leveling agents, thickeners, water repellents, and decolorizers. Known foaming agents and the like can be used.

As the adhesive composition (b), one containing a solvent can be used in order to maintain good coating workability and the like. As the solvent, for example, toluene, xylene, ethyl acetate, butyl acetate, acetone, methyl ethyl ketone, hexane or the like can be used. When using a water-based adhesive composition as the adhesive composition (b), water or an aqueous solvent mainly containing water can be used as the solvent.

The adhesive tape used in the present invention is produced, for example, by undergoing the step [I] of forming the expandable adhesive layer (A) by applying the adhesive composition (a) to a release liner and drying it. can do.
Among the adhesive tapes used in the present invention, the adhesive tape composed of the expandable adhesive layer (A) and the adhesive layer (B) has the steps [I] and [I]. Separately, a step [II] of forming the adhesive layer (B) by applying the adhesive composition (b) to a release liner and drying, and one side of the expandable adhesive layer (A). It can be produced by the step [III] of transferring the adhesive layer (B) and pressing them.
It is preferable that the expandable adhesive layer (A) does not substantially expand in the process of manufacturing the adhesive tape.

In addition, the adhesive tape used in the present invention may include a nonwoven fabric layer, a resin film layer, or a metal layer (Z) between the expansive adhesive layer (A) and the adhesive layer (B), if necessary. ) Can be used. Since such an adhesive tape has good rigidity, it is excellent in workability for application.

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 or the like, and in order to satisfy the tensile strength of the non-woven fabric, a paper making step may be carried out if necessary. Then, a one-step impregnation treatment in which polyamide is added and coating is performed after drying, a two-step impregnation treatment using viscose or a thermoplastic resin as a binder may be performed. As the resin film, a resin film layer formed by using a plastic film such as a polyester film, a polyethylene film, a polypropylene film, a polyvinyl chloride film, a polyimide film or the like, and as a layer made of a metal, a metal layer such as aluminum or copper Are listed.

As the layer (Z), it is preferable to use a layer having a thickness of 1 μm to 200 μm.

In the adhesive tape having the layer (Z), for example, the step [I] in which the expandable adhesive layer (A) is formed by applying the adhesive composition (a) to a release liner and drying it, [the step [I]. Separately from I], the step [II] of forming the adhesive layer (B) by applying the adhesive composition (b) to a release liner and drying it, and the step of forming the expandable adhesive layer (A). By carrying out a step [IV] of laminating the layer (Z) on one surface and a step [V] of transferring the adhesive layer (B) to the surface composed of the layer (Z) and pressing them. It can be manufactured.

(Preparation example 1)
<Preparation of adhesive composition (a-1)>
Styrene-butadiene block copolymer S having a weight average molecular weight of 300,000 (a mixture of a triblock copolymer and a diblock copolymer. A ratio of the diblock copolymer to 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 mass parts, terpene phenol-based tackifying resin (softening point 115° C., molecular weight 1000). ) A mixture of 100 parts by mass was dissolved in toluene to obtain an adhesive composition (a-1).

(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-phenolic tackifying resin (softening point 115° C., molecular weight 1000) used in Preparation Example 1 was changed from 100 parts by mass to 65 parts by mass. (A-2) was obtained.

(Preparation example 3)
<Preparation of adhesive composition (a-3)>
In a reaction vessel equipped with a stirrer, a reflux condenser, a thermometer, a dropping funnel and a 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. , 4-hydroxybutyl acrylate 0.1 part by mass and 2,2′-azobisisobutylnitrile 0.1 part by mass as a polymerization initiator are dissolved in 100 parts by mass of ethyl acetate and polymerized at 70° C. for 10 hours. Thus, an acrylic copolymer Z solution having a weight average molecular weight of 800,000 was obtained.

Next, 30 parts by mass of polymerized rosin ester tackifying resin D-135 (manufactured by Arakawa Chemical Industry Co., Ltd.) was added to 100 parts by mass of the acrylic copolymer Z, and ethyl acetate was added and mixed, followed by Japan. 1.1 parts by mass of "Coronate L-45" (isocyanate type crosslinking agent, solid content 45% by mass) manufactured by Polyurethane Industry Co., Ltd. was added and stirred for 15 minutes to obtain an adhesive (a-2).

<Preparation of adhesive tape>

(Creation example 1)
100% by mass of the total solid content of the adhesive composition (a-1) is provided on the surface of a release paper having a thickness of 130 μm, which has a polyethylene layer on both sides of a high-quality paper and has a silicone-based release treatment agent layer on one side of the polyethylene layer. 10 parts by mass of F-36D (a heat-expandable microcapsule, manufactured by Matsumoto Yushi-Seiyaku Co., Ltd., initial particle size 10 to 16 μm, expansion start temperature 70 to 80° C.) as a swelling agent and stirred for 10 minutes. , Was coated using a rod-shaped metal applicator so that the thickness after drying was 90 μm, and dried for 10 minutes with a dryer set at 65° C. to prepare an expansive adhesive layer (A-1). .. The expansive adhesive layer (A-1) is laminated on a release paper different from the one described above, and the expansive adhesive layer ( An adhesive tape consisting of A-1) was obtained.

Next, the adhesive composition (a-1) was applied to the surface of a release paper having a thickness of 130 μm, which has a polyethylene layer on both sides of a woodfree paper and a silicone release treatment agent layer on one side of the polyethylene layer. An adhesive layer (B-1) was prepared by applying a coating using a rod-shaped metal applicator so that the thickness after drying was 90 μm, and drying for 10 minutes with a dryer set at 65° C.
The expandable adhesive layer (A-1) is attached to the adhesive layer (B-1) obtained above on the other surface, and then pressure-laminating at 4 kgf/cm ² is applied to laminate the expandable adhesive layer (A-1). An adhesive tape 1 in which the agent layer (A-1) and the adhesive layer (B-1) were laminated was obtained.

(Creation example 2)
An expansive adhesive layer (A-1) and an adhesive layer (B-1) were prepared in the same manner as in Example 1, and the expansive adhesive layer (A-1) was used as a nonwoven fabric having a thickness of 35 μm. After sticking on one side and sticking the adhesive layer (B-1) obtained above on the other side, laminating by pressing at 80° C. at 4 kgf/cm ² gives an expansive adhesive layer ( An adhesive tape 2 in which A-1) and the adhesive layer (B-1) were laminated was obtained.

(Creation example 3)
The expandable adhesive layer (A-2) and the adhesive layer were prepared in the same manner as in Example 1 except that the adhesive composition (a-2) was used instead of the adhesive composition (a-1). An adhesive tape made of (B-2) was obtained. The expandable adhesive layer (A-1) was attached to one side of a nonwoven fabric having a thickness of 35 μm, and the adhesive layer (B-1) obtained above was attached to the other side thereof, and then 4 kgf at 80° C. The pressure-sensitive adhesive tape 3 in which the expansive adhesive layer (A-1) and the adhesive layer (B-1) were laminated on the non-woven fabric was obtained by laminating under pressure of /cm ² .

(Creation example 4)
An adhesive layer (B-1) was prepared in the same manner as in Example 1, the adhesive layer (B-1) was attached to one surface of a non-woven fabric having a thickness of 35 μm, and the other surface was also formed as described above. After the obtained adhesive layer (B-1) was attached, pressure was applied at 4 kgf/cm ² at 80° C. for lamination to obtain an adhesive tape 4 in which the adhesive layer (B-1) was laminated on the nonwoven fabric.

(Creation example 5)
Using the same method as in Example 1 except that the adhesive composition (a-3) was used instead of the adhesive composition (a-1), two adhesive tapes each composed of the adhesive layer (B-3) were used. I made one. After the adhesive layer (B-3) was attached to one side of a polyethylene-based foam substrate having a thickness of 100 μm and the adhesive layer (B-3) obtained above was attached to the other side, 4 kgf By laminating under pressure of /cm ² , an adhesive tape 5 having the adhesive layer (B-1) laminated on the foam was obtained.

[Production]
(Example 1)
The adhesive tape 1 was cut into strips having a length of 64 mm x a width of 1 mm and a length of 43 mm x a width of 1 mm. The (A-1) side of the adhesive tape was attached to a polycarbonate plate 1 having a long side of 65 mm, a short side of 45 mm, and a thickness of 2 mm. At this time, an adhesive tape cut to a length of 64 mm on the long side and an adhesive tape cut to a length of 43 mm on the short side were attached to the place opened 1 mm from the outside of the polycarbonate plate 1 so as to form a frame shape. .. Further, the adhesive tapes cut into strips were attached so that the ends thereof overlap each other. A polycarbonate plate 1 provided with the adhesive tape and a polycarbonate plate 2 having a long side of 65 mm, a short side of 45 mm and a thickness of 2 mm are laminated, and the polycarbonate plate 1 and the polycarbonate plate 2 are joined by the frame-shaped test tape. A test piece was prepared (FIG. 4). Next, a weight is put on the entire surface of the adhesive tape attached to the test piece so that the weight of the polycarbonate plate 1 is 210 g, and the load of 1 N/cm ² is applied to the adhesive tape at 100° C. Was heated in the heating furnace for 30 minutes to expand (A-1), and then the test piece was allowed to cool to room temperature to obtain an article.

(Example 2)
An article was obtained in the same manner as in Example 1 except that the adhesive tape 2 was used instead of the adhesive tape 1.

(Example 3)
An article was obtained in the same manner as in Example 1 except that the adhesive tape 3 was used instead of the adhesive tape 1.

(Example 4)
The adhesive tape 2 was cut into strips having a length of 64 mm x a width of 1 mm and a length of 43 mm x a width of 1 mm. The (A-1) side of the adhesive tape was attached to a polycarbonate plate 1 having a long side of 65 mm, a short side of 45 mm, and a thickness of 2 mm. At this time, an adhesive tape cut to a length of 64 mm on the long side and an adhesive tape cut to a length of 43 mm on the short side were attached to the place opened 1 mm from the outside of the polycarbonate plate 1 so as to form a frame shape. .. Further, the adhesive tapes cut into strips were attached so that the ends thereof overlap each other.
Next, a polycarbonate plate 3 having a size of 65 mm in length×45 mm in width×2 mm in thickness and having two wedge-shaped recesses (step portions) of 65 mm in length×5 mm in width and 30 μm in depth on its surface was prepared. .. The polycarbonate plate 1 provided with the test tape and the polycarbonate plate 3 are laminated so that the two recesses and the frame portion of the adhesive tape attached to the polycarbonate plate 1 overlap each other, and the polycarbonate plate 1 and the polycarbonate plate 3 were joined together with the frame-shaped test tape to prepare a test piece (FIG. 5). Next, a weight is put on the entire surface of the adhesive tape attached to the test piece so that the total weight of the polycarbonate plate 1 becomes 210 g, and a load of 1 N per unit area of the adhesive tape is applied at 100° C. Was heated in the heating furnace for 30 minutes to expand (A-1), and then the test piece was allowed to cool to room temperature to obtain an article.

(Comparative Example 1)
An article was obtained in the same manner as in Example 1 except that the adhesive tape 4 was used instead of the adhesive tape 1.

(Comparative example 2)
An article was obtained in the same manner as in Example 1 except that the adhesive tape 5 was used instead of the adhesive tape 1.

(Comparative example 4)
An article was obtained in the same manner as in Example 5, except that the adhesive tape 5 was used instead of the adhesive tape 1.

[Evaluation of waterproofness]
The articles obtained in Examples and Comparative Examples were allowed to stand at a water depth of 1 m for 30 minutes (according to IPX7 of JIS C0920). After the standing, the test piece was visually observed and evaluated according to the following evaluation criteria.
◯: Water did not infiltrate into the inside (the central portion of the test piece) of the test piece, which was surrounded by the frame-shaped tape.
X: Water had infiltrated into the inside (the central portion of the test piece) of the test piece, which was surrounded by the frame-shaped tape.

1 Adhesive tape A
2 Adhesive tape B
3 Adherend 4 Polycarbonate plate 1
5 Polycarbonate plate 2
6 Adhesive tape 1
7 Adhesive tape 2
8 Polycarbonate plate 3
9 steps

Claims (8)

A part where two or more adhesive tapes having an expandable adhesive layer (A) are arranged such that their ends are overlapped or close to each other and one surface side of the adhesive tape constitutes an adherend (C1) ( c1-1) step [1], step [2] of applying the other surface side of the adhesive tape to another adherend (C2), and stimulating the expandable adhesive layer (A) [3] of providing an adhesive tape (A1) and the step (4) of expanding the expandable adhesive layer (A) by the stimulus to form an expandable adhesive layer (A1). A method for manufacturing an article adhered via an expanded material. Expansion coefficient in the thickness direction of the expandable adhesive layer (A) [thickness of thermoplastic thermal expansion adhesive layer (A1) after heating/thermoplastic thermal expansion adhesive layer (A) before heating] Thickness]×100 is 150% or more. The method for producing an article according to claim 1, wherein The expandable adhesive layer (A) has an adhesive layer (B) on at least one surface side, and the expansion ratio in the thickness direction of the adhesive layer (B) [adhesive layer (B1) after heating] Thickness/adhesive layer (B) thickness before heating]×100 is 120% or less. The method for producing an article according to claim 1, wherein the expandable adhesive layer (A) has an adhesive force of 0.5 N/20 mm or more. The method for producing an article according to any one of claims 1 to 4, wherein the stimulus in the step [3] is heat. The expandable adhesive layer (A) is a layer containing a thermoplastic resin and a thermal expansion capsule having an expansion start temperature in the range of 70°C to 120°C. Manufacturing method of article. The storage elastic modulus of the thermoplastic resin measured by a dynamic viscoelastic spectrum at 1 Hz in the range of 70° C. to 120° C. is in the range of 1.0×10 ² Pa to 1.0×10 ⁷ Pa. 7. The method for manufacturing the article according to 6. In the step [1], the expansive adhesive layer (A) of the adhesive tape is pressure-bonded to the portion (c1-1) constituting the adherend (C1) with a force of 0.1 N/cm ² or more. The method for producing an article according to claim 1, further comprising a step.

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