Double-sided adhesive tape

Abstract

To provide a double-sided adhesive tape capable of exhibiting an excellent impact resistance.SOLUTION: A double-sided adhesive tape 100 is a double-sided adhesive tape to be used in fixation of components included in a mobile instrument. The double-sided adhesive tape includes adhesive layers 10a, 10b, and 10c. The adhesive layer is composed of an adhesive composition. The adhesive composition includes an organic hollow filler.SELECTED DRAWING: Figure 1

Description

Technical Field

[0006] , , , , , , , , ,

[0001] The present invention relates to a double-sided adhesive tape.

Background Art

[0002] In recent years, with the trend of the improvement of various performances of mobile devices, the improvement of various performances of various components adopted in the mobile devices has also been demanded. In mobile devices, a double-sided adhesive tape may be adopted for joining a housing or the like. In recent years, the improvement of various performances has also been demanded for this double-sided adhesive tape.

[0003] Mobile devices are at risk of falling depending on their usage form. Therefore, mobile devices with high impact resistance are demanded. In order to improve the impact resistance of mobile devices, an impact absorbing member may be provided outside the housing. However, in such a form, there is a risk that the size of the mobile device may increase or the design may be impaired.

[0004] Therefore, it is desired to impart excellent impact resistance to the double-sided adhesive tape that can be provided inside the mobile device.

[0005] Recently, a double-sided adhesive sheet having impact resistance has been reported (Patent Document 1). This double-sided adhesive sheet requires a foam base material to exhibit impact resistance. However, the foam breaks when it stretches or is subjected to a force beyond a certain level, and its area becomes smaller or it becomes thinner. As a result, the bubble portion of the foam occupies a large part of the adhesive portion, and there is a problem that the adhesiveness decreases.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] The object of the present invention is to provide a double-sided adhesive tape that can exhibit excellent impact resistance. [Means for solving the problem]

[0008] The double-sided adhesive tape of the present invention is A double-sided adhesive tape used to secure components included in mobile devices, A double-sided adhesive tape including an adhesive layer, The adhesive layer is formed from an adhesive composition, The adhesive composition contains an organic hollow filler.

[0009] In one embodiment, the specific gravity of the above-mentioned organic hollow filler is 0.01 to 1.2.

[0010] In one embodiment, the average particle size of the above-mentioned organic hollow filler is 5 μm to 70 μm.

[0011] In one embodiment, the above-mentioned organic hollow filler is an acrylonitrile-based hollow filler.

[0012] In one embodiment, the double-sided adhesive tape of the present invention has a thickness of 100 μm or more.

[0013] In one embodiment, the adhesive composition comprises at least one selected from a monomer component (m) and a polymer component (P) obtained by polymerization of the monomer component (m), wherein the monomer component (m) comprises an alkyl (meth)acrylate having an alkyl group having 4 to 18 carbon atoms at its ester terminus.

[0014] In one embodiment, the content of alkyl (meth)acrylate having an alkyl group with 4 to 18 carbon atoms at its ester terminus in the monomer component (m) is 50% to 100% by weight.

[0015] In one embodiment, the double-sided adhesive tape of the present invention is used for fixing a display portion or a display protection member included in a mobile device to a housing.

Advantages of the Invention

[0016] According to the present invention, it is possible to provide a double-sided adhesive tape capable of exhibiting excellent impact resistance.

Brief Description of the Drawings

[0017] [Figure 1] It is a schematic cross-sectional view of a double-sided adhesive tape according to one embodiment of the present invention. <00000​​​​​​​​​​​​​​​​​​​​​​​​​​​​

[0023] The double-sided adhesive tape of the present invention preferably has (n-1) interfaces in its adhesive layer laminate. These interfaces objectively indicate that the adhesive layer laminate is composed of n or more adhesive layers. These interfaces can be observed, for example, by differential interferometry using an Olympus LEXT OLS 4000.

[0024] The double-sided adhesive tape of the present invention may include any other layers as long as it includes an adhesive layer laminate composed of n or more adhesive layers stacked on top of each other, without impairing the effects of the present invention. Preferably, the double-sided adhesive tape of the present invention consists of an adhesive layer laminate composed of n or more adhesive layers stacked on top of each other, in that it can better exhibit the effects of the present invention.

[0025] The thickness of the double-sided adhesive tape of the present invention is preferably 100 μm or more, more preferably 100 μm to 1000 μm, even more preferably 100 μm to 500 μm, and particularly preferably 100 μm to 300 μm, in order to better exhibit the effects of the present invention.

[0026] Figure 1 is a schematic cross-sectional view of a double-sided adhesive tape according to one embodiment of the present invention. In Figure 1, the double-sided adhesive tape 100 consists of three adhesive layers, having adhesive layer 10a, adhesive layer 10b, and adhesive layer 10c.

[0027] On the surface of the adhesive layer, for the purpose of protection until use and the like, any appropriate release liner may be provided as long as it does not impair the effects of the present invention. Examples of the release liner include a release liner having a release treatment layer on the surface of a base material (liner base material) such as paper or a plastic film, a fluorine-based polymer (such as polytetrafluoroethylene), and a release liner in which the surface of a base material (liner base material) such as paper or a plastic film is laminated with a polyolefin-based resin. Examples of the plastic film as the liner base material include a polyethylene film, a polypropylene film, a polybutene film, a polybutadiene film, a polymethylpentene film, a polyvinyl chloride film, a vinyl chloride copolymer film, a polyethylene terephthalate film, a polybutylene terephthalate film, a polyurethane film, and an ethylene-vinyl acetate copolymer film. The plastic film as the liner base material is preferably a polyethylene film. The above release treatment layer can be formed, for example, by surface-treating the above liner base material with a release treatment agent such as a silicone-based, long-chain alkyl-based, fluorine-based, or molybdenum sulfide agent.

[0028] The thickness of the release liner is preferably 1 μm to 500 μm, more preferably 3 μm to 450 μm, still more preferably 5 μm to 400 μm, and particularly preferably 10 μm to 300 μm.

[0029] The adhesive strength of the double-sided adhesive tape of the present invention is preferably 5 N / 10 mm to 50 N / 10 mm, more preferably 6 N / 10 mm to 40 N / 10 mm, still more preferably 7 N / 10 mm to 30 N / 10 mm, and particularly preferably 8 N / 10 mm to 20 N / 10 mm. If the adhesive strength of the double-sided adhesive tape of the present invention is within the above range, the function as a double-sided adhesive tape can be sufficiently exhibited.

[0030] <A-1. Adhesive Layer Laminate> The double-sided adhesive tape of the present invention may include an adhesive layer laminate. The adhesive layer laminate is composed of n or more adhesive layers laminated.

[0031] Each of the n adhesive layers constituting the adhesive layer laminate may all be adhesive layers of the same composition, or at least one may be an adhesive layer of a different composition.

[0032] The thickness of the adhesive layer laminate is preferably 100 μm or more, more preferably 100 μm to 1000 μm, still more preferably 100 μm to 500 μm, and particularly preferably 100 μm to 300 μm, in terms of more effectively exhibiting the effects of the present invention.

[0033] <A-2. Adhesive Layer> The adhesive layer is composed of an adhesive. As the type of the adhesive constituting the adhesive layer, any appropriate adhesive can be employed as long as the effects of the present invention are not impaired. Such adhesives can be, for example, adhesives formed from an adhesive composition containing one or more selected from the group consisting of various polymers (adhesive polymers) such as acrylic polymers, polyester polymers, urethane polymers, polyether polymers, rubber polymers, silicone polymers, polyamide polymers, and fluorine polymers as a base polymer (the main component among the polymer components, that is, the component occupying 50% by weight or more).

[0034] The adhesive layer is formed from an adhesive composition.

[0035] The adhesive layer is formed from an adhesive composition by any appropriate method. Such methods include, for example, a method (direct method) of applying the adhesive composition, which is a forming material of the adhesive layer, onto any appropriate base material (for example, a base film) and drying it as necessary to form an adhesive layer on the base material, and a method (transfer method) of applying the adhesive composition onto a surface having releasability (release surface), drying it as necessary to form an adhesive layer on the surface having releasability (release surface), and transferring the adhesive layer onto any appropriate base material (for example, a base film). Examples of the surface having releasability (release surface) include the surface of the aforementioned release liner.

[0036] Any suitable coating method can be used for applying the adhesive composition, as long as it does not impair the effects of the present invention. Examples of such coating methods include roll coating, gravure coating, reverse coating, roll brushing, spray coating, air knife coating, and extrusion coating using a die coater. To cure the coating layer formed by the coating, irradiation with active energy rays such as ultraviolet light may be performed.

[0037] From the viewpoint of promoting the crosslinking reaction and improving manufacturing efficiency, the drying of the adhesive composition may be carried out under heating. The drying temperature can typically be 40°C to 150°C, and preferably 60°C to 130°C. After drying the adhesive composition, aging may be performed for the purpose of adjusting the migration of components within the adhesive layer, promoting the crosslinking reaction, and alleviating any strain that may exist within the adhesive layer.

[0038] The thickness of the adhesive layer can be appropriately set depending on the final thickness of the adhesive layer laminate and the number of adhesive layers. The thickness of such an adhesive layer is preferably 10 μm to 1000 μm, more preferably 20 μm to 700 μm, even more preferably 30 μm to 500 μm, particularly preferably 40 μm to 300 μm, and most preferably 50 μm to 200 μm.

[0039] The light transmittance of the adhesive layer in the XY and Z directions is preferably 5% or less, more preferably 3% or less, even more preferably 1% or less, even more preferably 0.5% or less, particularly preferably 0.1% or less, and most preferably 0.04% or less. If the light transmittance of the adhesive layer in the XY and Z directions is within the above range, the adhesive layer can exhibit excellent light-shielding properties. The light transmittance of the adhesive layer in the XY direction is preferably 0.03% or less, more preferably 0.02% or less, and even more preferably 0.01% or less. The light transmittance of the adhesive layer in the Z direction is preferably 0.03% or less, more preferably 0.02% or less, and even more preferably 0.01% or less.

[0040] <A-2-1. Adhesive Composition> The adhesive composition contains an organic hollow filler. The organic hollow filler contained in the adhesive composition may be only one kind or two or more kinds. By the adhesive composition containing an organic hollow filler, a double-sided adhesive tape capable of exhibiting excellent impact resistance can be provided.

[0041] The adhesive composition preferably contains at least one selected from a monomer component (m) and a polymer component (P) obtained by polymerization of the monomer component (m). That is, the adhesive composition preferably takes forms such as a form (Form 1) in which the polymer component (P) is contained and the monomer component (m) is substantially not contained, a form (Form 2) in which the monomer component (m) is contained and the polymer component (P) is substantially not contained, and a form (Form 3) in which both the monomer component (m) and the polymer component (P) are contained.

[0042] The form (Form 1) in which the polymer component (P) is contained and the monomer component (m) is substantially not contained is a form in which the polymer component (P) is substantially formed by polymerization of the monomer component (m) in the step of preparing the adhesive composition.

[0043] The form (Form 2) in which the monomer component (m) is contained and the polymer component (P) is substantially not contained is a form in which polymerization of the monomer component (m) has not substantially occurred and the polymer component (P) has not yet been formed in the step of preparing the adhesive composition. In this form, for example, the polymer component (P) can be formed by curing a coating layer formed by coating the prepared adhesive composition by irradiation with active energy rays such as ultraviolet irradiation.

[0044] In the form containing both monomer component (m) and polymer component (P) (Form 3), during the preparation of the adhesive composition, a portion of the monomer component (m) polymerizes to form a partial polymer, while unreacted monomer component (m) remains. In this form, for example, the polymer component (P) can be formed by curing the coating layer formed by applying the prepared adhesive composition with active energy ray irradiation such as ultraviolet irradiation.

[0045] In the case of the above-described form 1 (a form containing polymer component (P) and substantially free of monomer component (m)), the content of polymer component (P) in the adhesive composition is preferably 50% to 100% by weight, more preferably 60% to 100% by weight, even more preferably 70% to 100% by weight, and particularly preferably 80% to 100% by weight, when the total amount of the adhesive composition is 100 parts by weight.

[0046] In the case of the above-described form 2 (a form containing monomer component (m) and substantially not containing polymer component (P)), the content of monomer component (m) in the adhesive composition is preferably 50% to 100% by weight, more preferably 60% to 100% by weight, even more preferably 70% to 100% by weight, and particularly preferably 80% to 100% by weight, when the total amount of the adhesive composition is 100 parts by weight.

[0047] In the case of the above-described form 3 (a form containing both monomer component (m) and polymer component (P)), the total content ratio of polymer component (P) and monomer component (m) in the adhesive composition is preferably 50% to 100% by weight, more preferably 60% to 100% by weight, even more preferably 70% to 100% by weight, and particularly preferably 80% to 100% by weight, when the total amount of the adhesive composition is 100 parts by weight.

[0048] The adhesive composition may contain any suitable coloring agent, as long as it does not impair the effects of the present invention, from the viewpoint of adjusting light transmittance (light shielding). Conventional known pigments and dyes can be used as such coloring agents. Examples of pigments include inorganic pigments such as carbon black, zinc carbonate, zinc oxide, zinc sulfide, talc, kaolin, calcium carbonate, titanium dioxide, silica, lithium fluoride, calcium fluoride, barium sulfate, alumina, zirconia, iron oxide pigments, iron hydroxide pigments, chromium oxide pigments, spinel-type calcined pigments, chromate pigments, chromium vermilion pigments, Prussian blue pigments, aluminum powder pigments, bronze powder pigments, silver powder pigments, and calcium phosphate, as well as organic pigments such as phthalocyanine pigments, azo pigments, condensed azo pigments, azo lake pigments, anthraquinone pigments, perylene / perinone pigments, indigo pigments, thioindigo pigments, isoindolinone pigments, azomethine pigments, dioxazine pigments, quinacridone pigments, aniline black pigments, and triphenylmethane pigments. Examples of dyes include azo dyes, anthraquinones, quinophthalones, styryl dyes, diphenylmethane, triphenylmethane, oxazines, triazines, xanthan gums, azomethine, acridines, and diazines. The coloring agent may be one type or two or more types.

[0049] Specific examples of black colorants include carbon black, graphite, copper oxide, manganese dioxide, aniline black, perylene black, titanium black, cyanine black, activated carbon, ferrite (non-magnetic ferrite, magnetic ferrite, etc.), magnetite, chromium oxide, iron oxide, molybdenum disulfide, chromium complexes, and anthraquinone-based colorants.

[0050] The content of the colorant in the adhesive composition is preferably less than 30% by weight, more preferably less than 20% by weight, even more preferably less than 13% by weight, particularly preferably less than 10% by weight, and most preferably less than 8% by weight.

[0051] The adhesive composition may contain any suitable other components as long as the effects of the present invention are not impaired. Such other components include, for example, resin components other than the polymer component (P), tackifiers, crosslinking agents, inorganic fillers, organic fillers, metal powders, pigments, foils, softeners, anti-aging agents, conductive agents, ultraviolet absorbers, antioxidants, light stabilizers, surface lubricants, leveling agents, corrosion inhibitors, heat stabilizers, polymerization inhibitors, lubricants, solvents, catalysts, and the like.

[0052] <A-2-1-1. Organic hollow filler> The adhesive composition contains an organic hollow filler. By including an organic hollow filler in the adhesive composition, it is possible to provide a double-sided adhesive tape that exhibits excellent impact resistance.

[0053] The organic hollow filler may be only one kind or two or more kinds.

[0054] The organic hollow filler is an organic filler having a hollow structure, and typically includes at least one selected from an organic hollow filler and an organic-inorganic hybrid hollow filler composed of an organic and inorganic composite material.

[0055] The organic hollow filler is a hollow filler composed of an organic substance, and typically is a hollow filler composed of a polymer. Examples of the monomer used to form such a polymer include acrylonitrile, vinyl chloride, vinylidene chloride, styrene, vinyl acetate, (meth)acrylate, and the like. The organic hollow filler has a main component (preferably 50% by weight or more in terms of weight ratio) composed of an organic substance, and its surface may be coated with a powder (for example, calcium carbonate, talc, titanium oxide, etc.).

[0056] In preferred embodiments of the present invention, in order to better express the effects of the present invention, the polymer constituting the organic hollow filler is preferably a polymer obtained from a monomer containing an acrylic acid ester (acrylic acid ester polymer) and a polymer obtained from a monomer containing acrylonitrile (acrylonitrile polymer), and more preferably a polymer obtained from a monomer containing acrylonitrile (acrylonitrile polymer). That is, in preferred embodiments of the present invention, in order to better express the effects of the present invention, the organic hollow filler is preferably a hollow filler composed of an acrylonitrile polymer (acrylonitrile hollow filler).

[0057] Examples of hollow fillers made of acrylonitrile include Matsumoto Microsphere F-35, Matsumoto Microsphere F-65, Matsumoto Microsphere FN80SDE, and Matsumoto Microsphere MFL-81GCA manufactured by Matsumoto Oil & Fat Pharmaceutical Co., Ltd., and Expancel 053-40 and Expancel 551DE40d42 manufactured by Nouryon.

[0058] The specific gravity of the organic hollow filler is preferably 0.01 to 1.20, more preferably 0.02 to 1.10, even more preferably 0.05 to 1.00, even more preferably 0.08 to 0.80, particularly preferably 0.10 to 0.50, and most preferably 0.12 to 0.30, in order to better exhibit the effects of the present invention.

[0059] The average particle size of the organic hollow filler is preferably 5 μm to 70 μm, more preferably 7 μm to 60 μm, even more preferably 10 μm to 50 μm, particularly preferably 12 μm to 40 μm, and most preferably 15 μm to 35 μm, in order to better exhibit the effects of the present invention.

[0060] The heat resistance of the organic hollow filler is preferably 100°C or higher, more preferably 110°C to 150°C, still more preferably 115°C to 140°C, and particularly preferably 120°C to 140°C in terms of more effectively expressing the effects of the present invention.

[0061] In the case of the above-mentioned Form 1 (a form containing the polymer component (P) and substantially not containing the monomer component (m)), when the total amount of the polymer component (P) is 100 parts by weight, the content ratio of the organic hollow filler in the adhesive composition is preferably 0.05% to 50% by weight, more preferably 0.1% to 40% by weight, particularly preferably 1% to 30% by weight, and most preferably 1% to 20% by weight.

[0062] In the case of the above-mentioned Form 2 (a form containing the monomer component (m) and substantially not containing the polymer component (P)), when the total amount of the monomer component (m) is 100 parts by weight, the content ratio of the organic hollow filler in the adhesive composition is preferably 0.05% to 50% by weight, more preferably 0.1% to 40% by weight, particularly preferably 1% to 30% by weight, and most preferably 1% to 20% by weight.

[0063] In the case of the above-mentioned Form 3 (a form containing both the monomer component (m) and the polymer component (P)), when the total amount of the polymer component (P) and the monomer component (m) is 100 parts by weight, the content ratio of the organic hollow filler in the adhesive composition is preferably 0.05% to 50% by weight, more preferably 0.1% to 40% by weight, particularly preferably 1% to 30% by weight, and most preferably 1% to 20% by weight.

[0064] <A-2-1-2. Monomer component (m)> The monomer component (m) can adopt any suitable monomer component as long as the effects of the present invention are not impaired.

[0065] The monomer component (m) preferably includes an alkyl (meth)acrylate having an alkyl group with 4 to 18 carbon atoms at its ester terminus. There may be only one alkyl (meth)acrylate having an alkyl group with 4 to 18 carbon atoms at its ester terminus, or there may be two or more.

[0066] Alkyl (meth)acrylates having an alkyl group with 4 to 18 carbon atoms at the ester end include, specifically, n-butyl (meth)acrylate, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, n-heptyl (meth)acrylate, n-octyl (meth)acrylate, n-nonyl (meth)acrylate, n-decyl (meth)acrylate, n-undecyl (meth)acrylate, and n-dodecyl (meth)acrylate. Alkyl(meth)acrylates having a linear alkyl group with 4 to 18 carbon atoms at the ester end, such as n-tridecyl(meth)acrylate, n-tetradecyl(meth)acrylate, n-pentadecyl(meth)acrylate, n-hexadecyl(meth)acrylate, n-heptadecyl(meth)acrylate, and n-octadecyl(meth)acrylate; t-butyl(meth)acrylate, isobutyl(meth)acrylate; Examples include alkyl(meth)acrylates having a branched alkyl group with 4 to 18 carbon atoms at the ester end, such as t-acrylate, isopentyl(meth)acrylate, t-pentyl(meth)acrylate, neopentyl(meth)acrylate, isohexyl(meth)acrylate, isoheptyl(meth)acrylate, 2-ethylhexyl(meth)acrylate, isooctyl(meth)acrylate, isononyl(meth)acrylate, isodecyl(meth)acrylate, 2-propylheptyl(meth)acrylate, isoundecyl(meth)acrylate, isododecyl(meth)acrylate, isotridecyl(meth)acrylate, isomistyryl(meth)acrylate, isopentadecyl(meth)acrylate, isohexadecyl(meth)acrylate, isoheptadecyl(meth)acrylate, and isostearyl(meth)acrylate. Among these alkyl (meth)acrylates having C4-C18 alkyl groups at their ester ends, alkyl (meth)acrylates having C4-C12 linear alkyl groups at their ester ends are preferred in that they can exhibit superior impact resistance, and alkyl (meth)acrylates having C4-C8 linear alkyl groups at their ester ends are more preferred, and specifically, n-butyl (meth)acrylate is particularly preferred.

[0067] The content of alkyl (meth)acrylate having an alkyl group with 4 to 18 carbon atoms at the ester terminus in the monomer component (m) is preferably 50% to 100% by weight, more preferably 70% to 99.5% by weight, even more preferably 90% to 99% by weight, particularly preferably 91% to 98% by weight, and most preferably 92% to 97% by weight. If the content of alkyl (meth)acrylate having an alkyl group with 4 to 18 carbon atoms at the ester terminus in the monomer component (m) is within the above range, a double-sided adhesive tape that exhibits superior impact resistance can be provided.

[0068] The monomer component (m) preferably contains (meth)acrylic acid, and more preferably contains acrylic acid. The content of (meth)acrylic acid in the total amount of monomer component (m) is preferably 1% to 10% by weight, more preferably 1% to 8% by weight, even more preferably 2% to 7% by weight, particularly preferably 2% to 6% by weight, and most preferably 2.5% to 5.5% by weight. If the content of (meth)acrylic acid in monomer component (m) is within the above range, a double-sided adhesive tape that exhibits superior impact resistance can be provided.

[0069] The monomer component (m) may contain other monomers. Such other monomers may be one type or two or more types.

[0070] The content of other monomers in the total amount of monomer component (m) is preferably 0% to 10% by weight, more preferably 0% to 8% by weight, even more preferably 0% to 6% by weight, particularly preferably 0% to 4% by weight, and most preferably 0% to 2% by weight. By adjusting the content of other monomers in monomer component (m) within the above range, a double-sided adhesive tape that exhibits superior impact resistance can be provided.

[0071] Other monomers include, for example, alicyclic structure-containing acrylic monomers, alkyl (meth)acrylates having C1-C3 alkyl groups at their ester ends, hydroxyl group-containing monomers, carboxyl group-containing monomers other than (meth)acrylic acid, nitrogen-based cyclic structure-containing monomers, cyclic ether group-containing monomers, glycol-based acrylic ester monomers, styrene-based monomers, amide group-containing monomers, amino group-containing monomers, imide group-containing monomers, vinyl ether monomers, silane-based monomers, and polyfunctional monomers.

[0072] The acrylic monomer containing an alicyclic structure is preferably an acrylic monomer having a cyclic aliphatic hydrocarbon structure. The number of carbon atoms in the cyclic aliphatic hydrocarbon structure is preferably 3 or more, more preferably 6 to 24, even more preferably 6 to 18, and particularly preferably 6 to 12. Specific examples of such alicyclic structure-containing acrylic monomers include cyclopropyl (meth)acrylate, cyclobutyl (meth)acrylate, cyclopentyl (meth)acrylate, cyclohexyl (meth)acrylate, cycloheptyl (meth)acrylate, cyclooctyl (meth)acrylate, isobornyl (meth)acrylate, and dicyclopentanyl (meth)acrylate.

[0073] Examples of alkyl (meth)acrylates having an alkyl group with 1 to 3 carbon atoms at the ester terminus include, for example, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, and isopropyl (meth)acrylate.

[0074] Examples of hydroxyl group-containing monomers include, for example, hydroxyalkyl (meth)acrylates such as 2-hydroxybutyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, and 12-hydroxylauryl (meth)acrylate; hydroxyalkylcycloalkane (meth)acrylates such as (4-hydroxymethylcyclohexyl)methyl (meth)acrylate; and other hydroxyl group-containing monomers such as hydroxyethyl (meth)acrylamide, allyl alcohol, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, and diethylene glycol monovinyl ether. Among these hydroxyl group-containing monomers, hydroxyalkyl (meth)acrylates are preferred in that they can exhibit superior impact resistance, hydroxyalkyl (meth)acrylates having a hydroxyalkyl group with 2 to 6 carbon atoms are more preferred, and 2-hydroxyethyl (meth)acrylate and 4-hydroxybutyl (meth)acrylate are even more preferred.

[0075] Examples of carboxyl group-containing monomers other than (meth)acrylic acid include, for example, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, crotonic acid, and isocrotonic acid.

[0076] Examples of nitrogen-containing cyclic monomers include, for example, lactam-based vinyl monomers such as N-vinylpyrrolidone, N-vinyl-ε-caprolactam, and methylvinylpyrrolidone; vinyl monomers having nitrogen-containing heterocycles such as vinylpyridine, vinylpiperidone, vinylpyrimidine, vinylpiperazine, vinylpyrazine, vinylpyrrole, vinylimidazole, vinyloxazole, and vinylmorpholine; and (meth)acrylic monomers containing heterocycles such as morpholine rings, piperidine rings, pyrrolidine rings, and piperazine rings (e.g., N-acryloylmorpholine, N-acryloylpiperidine, N-methacryloylpiperidine, N-acryloylpyrrolidine, etc.).

[0077] Examples of cyclic ether group-containing monomers include epoxy group-containing monomers such as glycidyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate glycidyl ether, methyl glycidyl (meth)acrylate, and allyl glycidyl ether; and oxetane group-containing monomers such as 3-oxetanylmethyl (meth)acrylate, 3-methyl-oxetanylmethyl (meth)acrylate, 3-ethyl-oxetanylmethyl (meth)acrylate, 3-butyl-oxetanylmethyl (meth)acrylate, and 3-hexyl-oxetanylmethyl (meth)acrylate.

[0078] Examples of glycol-based acrylic ester monomers include polyethylene glycol (meth)acrylate, polypropylene glycol (meth)acrylate, methoxyethylene glycol (meth)acrylate, and methoxypolypropylene glycol (meth)acrylate.

[0079] Examples of styrene monomers include, for instance, styrene and α-methylstyrene.

[0080] Examples of monomers containing amide groups include acrylamide, methacrylamide, diethylacrylamide, N-vinylpyrrolidone, N,N-dimethylacrylamide, N,N-dimethylmethacrylamide, N,N-diethylacrylamide, N,N-diethylmethacrylamide, N,N'-methylenebisacrylamide, N,N-dimethylaminopropylacrylamide, N,N-dimethylaminopropylmethacrylamide, diacetoneacrylamide, and N,N-hydroxyethylacrylamide.

[0081] Examples of amino group-containing monomers include aminoethyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, N,N-dimethylaminopropyl (meth)acrylate, and the like.

[0082] Examples of imide group-containing monomers include cyclohexylmaleimide, isopropylmaleimide, N-cyclohexylmaleimide, and itaconimide.

[0083] Examples of silane monomers include, for example, 3-acryloxypropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 4-vinylbutyltrimethoxysilane, 4-vinylbutyltriethoxysilane, 8-vinyloctyltrimethoxysilane, 8-vinyloctyltriethoxysilane, 10-methacryloyloxydecyltrimethoxysilane, 10-acryloyloxydecyltrimethoxysilane, 10-methacryloyloxydecyltriethoxysilane, and 10-acryloyloxydecyltriethoxysilane.

[0084] Examples of the polyfunctional monomer include ester compounds of polyhydric alcohols such as (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,2-ethylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,12-dodecanediol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, and tetramethylolmethane tri(meth)acrylate with (meth)acrylic acid; allyl (meth)acrylate; vinyl (meth)acrylate; divinylbenzene; epoxy acrylate; polyester acrylate; urethane acrylate; butyl di(meth)acrylate; hexyl di(meth)acrylate; and the like.

[0085] <A-2-1-3. Polymer Component (P)> The polymer component (P) is obtained by polymerization of the monomer component (m). The polymer component (P) is typically an acrylic polymer. The polymer component (P) may be only one kind or two or more kinds.

[0086] As a method for producing the polymer component (P), any appropriate production method can be adopted as long as the effects of the present invention are not impaired. Examples of such production methods include various radical polymerizations such as solution polymerization, active energy ray polymerization such as UV polymerization, bulk polymerization, and emulsion polymerization. As the polymerization conditions, any appropriate polymerization conditions can be adopted as long as the effects of the present invention are not impaired.

[0087] As the polymerization structure of the obtained polymer component (P), any appropriate polymerization structure can be adopted as long as the effects of the present invention are not impaired. Examples of such polymerization structures include random copolymers, block copolymers, graft copolymers, and the like.

[0088] As additives such as polymerization initiators, chain transfer agents, and emulsifiers used in radical polymerization, any suitable additives can be used within the limits that do not impair the effects of the present invention.

[0089] Examples of polymerization solvents that can be used in solution polymerization include ethyl acetate and toluene. The polymerization solvent may be a single solvent or two or more solvents.

[0090] Solution polymerization is carried out, for example, under a stream of an inert gas such as nitrogen, with the addition of a polymerization initiator, typically at a temperature of around 50°C to 70°C for 5 to 30 hours.

[0091] As polymerization initiators that can be used in solution polymerization, etc., any suitable thermal polymerization initiator can be used as long as it does not impair the effects of the present invention. There may be only one polymerization initiator or two or more. Examples of such polymerization initiators include 2,2'-azobisisobutyronitrile, 2,2'-azobis-2-methylbutyronitrile, 2,2'-azobis(2-methylpropionic acid)dimethyl, 4,4'-azobis-4-cyanovaleric acid, azobisisovaleronitrile, 2,2'-azobis(2-amidinopropane)dihydrochloride, and 2,2'-azobis[2-(5-methyl-2-imidazolin-2-yl) Azo initiators such as propane dihydrochloride, 2,2'-azobis(2-methylpropionamidine) disulfate, 2,2'-azobis(N,N'-dimethylene isobutylamidine), and 2,2'-azobis[N-(2-carboxyethyl)-2-methylpropionamidine]hydrate (VA-057, manufactured by Wako Pure Chemical Industries, Ltd.); persulfates such as potassium persulfate and ammonium persulfate, and di(2-ethylhexyl) Examples include peroxide-based initiators such as peroxydicarbonate, di(4-t-butylcyclohexyl)peroxydicarbonate, di-sec-butylperoxydicarbonate, t-butylperoxyneodecanoate, t-hexylperoxypivalate, t-butylperoxypivalate, dilauroyl peroxide, di-n-octanoyl peroxide, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, di(4-methylbenzoyl)peroxide, dibenzoyl peroxide, t-butylperoxyisobutyrate, 1,1-di(t-hexylperoxy)cyclohexane, t-butylhydroperoxide, and hydrogen peroxide; and redox initiators combining peroxides with reducing agents, such as combinations of persulfates and sodium bisulfite, or combinations of peroxides and sodium ascorbate.

[0092] The amount of polymerization initiator used is preferably 1 part by weight or less, more preferably 0.005 parts by weight to 1 part by weight, even more preferably 0.01 parts by weight to 0.7 parts by weight, and particularly preferably 0.02 parts by weight to 0.5 parts by weight, based on 100 parts by weight of the total amount of monomer component (m), in terms of being able to effectively advance the polymerization reaction.

[0093] As the chain transfer agent, any suitable chain transfer agent can be used as long as it does not impair the effects of the present invention. There may be only one chain transfer agent or two or more. Examples of such chain transfer agents include lauryl mercaptan, glycidyl mercaptan, mercaptoacetic acid, 2-mercaptoethanol, thioglycolic acid, 2-ethylhexyl thioglycolate, and 2,3-dimercapto-1-propanol.

[0094] The amount of chain transfer agent used is preferably 0.1 parts by weight or less per 100 parts by weight of the total amount of monomer component (m), in order to effectively promote the polymerization reaction.

[0095] As an emulsifier, any suitable emulsifier can be used as long as it does not impair the effects of the present invention. There may be only one emulsifier or two or more. Examples of such emulsifiers include anionic emulsifiers such as sodium lauryl sulfate, ammonium lauryl sulfate, sodium dodecylbenzenesulfonate, ammonium polyoxyethylene alkyl ether sulfate, and sodium polyoxyethylene alkylphenyl ether sulfate; and nonionic emulsifiers such as polyoxyethylene alkyl ethers, polyoxyethylene alkylphenyl ethers, polyoxyethylene fatty acid esters, and polyoxyethylene-polyoxypropylene block polymers.

[0096] From the viewpoint of polymerization stability and mechanical stability, the amount of emulsifier used is preferably 5 parts by weight or less, more preferably 0.3 to 5 parts by weight, even more preferably 0.4 to 3 parts by weight, and particularly preferably 0.5 to 1 part by weight, based on 100 parts by weight of the total amount of monomer component (m).

[0097] When performing UV polymerization, a photopolymerization initiator is preferably used.

[0098] As the photopolymerization initiator, any suitable photopolymerization initiator can be used as long as it does not impair the effects of the present invention. There may be only one type of photopolymerization initiator or two or more types. Examples of such photopolymerization initiators include benzoin ether-based photopolymerization initiators, acetophenone-based photopolymerization initiators, α-ketol-based photopolymerization initiators, aromatic sulfonyl chloride-based photopolymerization initiators, photoactive oxime-based photopolymerization initiators, benzoin-based photopolymerization initiators, benzyl-based photopolymerization initiators, benzophenone-based photopolymerization initiators, ketal-based photopolymerization initiators, thioxanthone-based photopolymerization initiators, and acylphosphine oxide-based photopolymerization initiators.

[0099] Examples of benzoin ether-based photopolymerization initiators include, for example, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isopropyl ether, benzoin isobutyl ether, 2,2-dimethoxy-1,2-diphenylethane-1-one (a commercially available product is, for example, "Irgacure 651," manufactured by BASF), and anisole methyl ether.

[0100] Examples of acetophenone-based photopolymerization initiators include, for example, 1-hydroxycyclohexylphenyl ketone (commercially available, for example, trade name "Irgacure 184", manufactured by BASF), 4-phenoxydichloroacetophenone, 4-t-butyl-dichloroacetophenone, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one (commercially available, for example, trade name "Irgacure 2959", manufactured by BASF), 2-hydroxy-2-methyl-1-phenyl-propan-1-one (commercially available, for example, trade name "Darocure 1173", manufactured by BASF), and methoxyacetophenone.

[0101] Examples of α-ketol-based photopolymerization initiators include 2-methyl-2-hydroxypropiophenone and 1-[4-(2-hydroxyethyl)-phenyl]-2-hydroxy-2-methylpropan-1-one.

[0102] Examples of aromatic sulfonyl chloride-based photopolymerization initiators include, for example, 2-naphthalenesulfonyl chloride.

[0103] Examples of photoactive oxime-based photopolymerization initiators include, for example, 1-phenyl-1,1-propanedione-2-(o-ethoxycarbonyl)-oxime.

[0104] Examples of benzoin-based photopolymerization initiators include, for example, benzoin.

[0105] Examples of benzyl-based photopolymerization initiators include, for example, benzyl.

[0106] Examples of benzophenone-based photopolymerization initiators include benzophenone, benzoylbenzoic acid, 3,3'-dimethyl-4-methoxybenzophenone, polyvinylbenzophenone, and α-hydroxycyclohexylphenyl ketone.

[0107] Examples of ketal-based photopolymerization initiators include, for example, benzyldimethyl ketal.

[0108] Examples of thioxanthone-based photopolymerization initiators include, for example, thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, 2,4-diethylthioxanthone, isopropylthioxanthone, 2,4-diisopropylthioxanthone, and dodecylthioxanthone.

[0109] Examples of acylphosphine-based photopolymerization initiators include, specifically, bis(2,6-dimethoxybenzoyl)phenylphosphine oxide, bis(2,6-dimethoxybenzoyl)(2,4,4-trimethylpentyl)phosphine oxide, bis(2,6-dimethoxybenzoyl)-n-butylphosphine oxide, bis(2,6-dimethoxybenzoyl)-(2-methylpropan-1-yl)phosphine oxide, bis(2,6-dimethoxybenzoyl)-(1-methylpropan-1-yl)phosphine oxide, and bis(2,6-dimethyl (Xybenzoyl)-t-butylphosphine oxide, bis(2,6-dimethoxybenzoyl)cyclohexylphosphine oxide, bis(2,6-dimethoxybenzoyl)octylphosphine oxide, bis(2-methoxybenzoyl)(2-methylpropan-1-yl)phosphine oxide, bis(2-methoxybenzoyl)(1-methylpropan-1-yl)phosphine oxide, bis(2,6-diethoxybenzoyl)(2-methylpropan-1-yl)phosphine oxide, bis(2,6-diethoxybenzoyl)(1-methylprop Pan-1-yl)phosphine oxide, bis(2,6-dibutoxybenzoyl)(2-methylpropan-1-yl)phosphine oxide, bis(2,4-dimethoxybenzoyl)(2-methylpropan-1-yl)phosphine oxide, bis(2,4,6-trimethylbenzoyl)(2,4-dipentoxyphenyl)phosphine oxide, bis(2,6-dimethoxybenzoyl)benzylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2-phenylpropylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2 - Phenylethylphosphine oxide, bis(2,6-dimethoxybenzoyl)benzylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2-phenylpropylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2-phenylethylphosphine oxide, 2,6-dimethoxybenzoylbenzylbutylphosphine oxide, 2,6-dimethoxybenzoylbenzyloctylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-2,5-diisopropylphenylphosphine oxide, bis(2,4,6-Trimethylbenzoyl)-2-methylphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-4-methylphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-2,5-diethylphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-2,3,5,6-tetramethylphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-2,4-di-n-butoxyphenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis(2,6-dimethoxybenzoyl) Examples include -2,4,4-trimethylpentylphosphine oxide, bis(2,4,6-trimethylbenzoyl)isobutylphosphine oxide, 2,6-dimethitoxybenzoyl-2,4,6-trimethylbenzoyl-n-butylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-2,4-dibutoxyphenylphosphine oxide, 1,10-bis[bis(2,4,6-trimethylbenzoyl)phosphine oxide]decane, and tri(2-methylbenzoyl)phosphine oxide.

[0110] From the viewpoint of exhibiting good polymerizability, the amount of photopolymerization initiator used is preferably 5 parts by weight or less, more preferably 0.01 to 5 parts by weight, even more preferably 0.05 to 3 parts by weight, particularly preferably 0.05 to 1.5 parts by weight, and most preferably 0.1 to 1 part by weight, based on 100 parts by weight of the total amount of monomer component (m).

[0111] When performing UV polymerization, polyfunctional (meth)acrylates are preferably used.

[0112] As the polyfunctional (meth)acrylate, any suitable polyfunctional (meth)acrylate can be used as long as it does not impair the effects of the present invention. The polyfunctional (meth)acrylate may be one type or two or more types. Specifically, such polyfunctional (meth)acrylates include, for example, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,2-ethylene glycol di(meth)acrylate, and 1,6- Examples include ester compounds of polyhydric alcohols such as xanediol di(meth)acrylate, 1,12-dodecanediol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, and tetramethylolmethane tri(meth)acrylate with (meth)acrylic acid; allyl(meth)acrylate; vinyl(meth)acrylate; divinylbenzene; epoxy acrylate; polyester acrylate; urethane acrylate; butyl di(meth)acrylate; hexyl di(meth)acrylate; and others.

[0113] From the viewpoint of exhibiting good crosslinking properties, the amount of polyfunctional (meth)acrylate used is preferably 5 parts by weight or less, more preferably 0.01 to 5 parts by weight, even more preferably 0.05 to 3 parts by weight, particularly preferably 0.05 to 1.5 parts by weight, and most preferably 0.1 to 1 part by weight, based on 100 parts by weight of the total amount of monomer component (m).

[0114] Any suitable UV polymerization method can be used as long as it does not impair the effects of the present invention. For example, such a UV polymerization method involves blending a photopolymerization initiator and, if necessary, a polyfunctional (meth)acrylate with a monomer component (m), and then irradiating it with ultraviolet light.

[0115] The weight average molecular weight of the polymer component (P) is preferably from 100,000 to 3,000,000, more preferably from 300,000 to 2,000,000, still more preferably from 500,000 to 1,500,000, and particularly preferably from 500,000 to 1,000,000 in terms of the double-sided adhesive tape of the present invention being able to exhibit more excellent impact resistance. The weight average molecular weight refers to a value measured by gel permeation chromatography (GPC) and calculated in terms of polystyrene conversion. Note that for the polymer component (P) obtained by active energy ray polymerization, it may be difficult to measure the weight average molecular weight.

[0116] <A-2-1-4. Tackifying resin> The adhesive composition may contain a tackifying resin. The tackifying resin may be only one kind or two or more kinds.

[0117] As the tackifying resin, any suitable tackifying resin can be adopted as long as the effects of the present invention are not impaired. Examples of such tackifying resins include phenolic tackifying resins, terpene tackifying resins, modified terpene tackifying resins, rosin tackifying resins, hydrocarbon tackifying resins, epoxy tackifying resins, polyamide tackifying resins, elastomer tackifying resins, ketone tackifying resins, and the like.

[0118] Phenolic tackifying resins include, for example, terpene phenol resins, hydrogenated terpene phenol resins, alkylphenol resins, and rosin phenol resins. Terpene phenol resins refer to polymers containing terpene residues and phenol residues, and are a concept that encompasses both copolymers of terpenes and phenol compounds (terpene-phenol copolymer resins) and homopolymers or copolymers of terpenes modified with phenol (phenol-modified terpene resins). Examples of terpenes that constitute such terpene phenol resins include monoterpenes such as α-pinene, β-pinene, and limonene (including d-isomers, l-isomers, and d / l-isomers (dipentene)). Hydrogenated terpene phenol resins are hydrogenated terpene phenol resins having a structure obtained by hydrogenating such terpene phenol resins, and are sometimes called hydrogenated terpene phenol resins. Alkylphenol resins are resins (oil-based phenol resins) obtained from alkylphenols and formaldehyde. Examples of alkylphenol resins include novolac type and resol type. Examples of rosinphenol resins include phenol-modified products of rosins or various rosin derivatives (including rosin esters, unsaturated fatty acid-modified rosins, and unsaturated fatty acid-modified rosin esters). Examples of rosinphenol resins include rosinphenol resins obtained by methods such as adding phenol to rosins or various rosin derivatives with an acid catalyst and then thermal polymerization.

[0119] Examples of terpene-based tackifying resins include polymers of terpenes (typically monoterpenes) such as α-pinene, β-pinene, d-limonene, l-limonene, and dipentene. Examples of single-molecule polymers of terpenes include α-pinene polymers, β-pinene polymers, and dipentene polymers.

[0120] Examples of modified terpene resins include styrene-modified terpene resins and hydrogenated terpene resins.

[0121] The concept of rosin-based tackifying resins encompasses both rosins and rosin derivative resins. Examples of rosins include unmodified rosins (raw rosins) such as gum rosin, wood rosin, and tall oil rosin; and modified rosins (hydrogenated rosin, disproportionated rosin, polymerized rosin, and other chemically modified rosins) obtained by hydrogenation, disproportionation, polymerization, etc.

[0122] Examples of rosin derivative resins include rosin esters such as unmodified rosin esters (esters of unmodified rosin and alcohols) and modified rosin esters (esters of modified rosin and alcohols); unsaturated fatty acid modified rosins obtained by modifying rosins with unsaturated fatty acids; unsaturated fatty acid modified rosin esters obtained by modifying rosin esters with unsaturated fatty acids; rosin alcohols obtained by reducing the carboxyl groups of rosins or rosin derivative resins (rosin esters, unsaturated fatty acid modified rosins, unsaturated fatty acid modified rosin esters, etc.); and metal salts thereof. Examples of rosin esters include methyl esters, triethylene glycol esters, glycerin esters, and pentaerythritol esters of unmodified rosin or modified rosin (e.g., hydrogenated rosin, disproportionated rosin, polymerized rosin, etc.).

[0123] Examples of hydrocarbon-based tackifying resins include aliphatic hydrocarbon resins, aromatic hydrocarbon resins, aliphatic cyclic hydrocarbon resins, aliphatic-aromatic petroleum resins (such as styrene-olefin copolymers), aliphatic-alicyclic petroleum resins, hydrogenated hydrocarbon resins, coumarone resins, and coumarone-indene resins.

[0124] In the case of Embodiment 1 described above, the content ratio of the tackifying resin in the adhesive composition is preferably 1 to 50 parts by weight, more preferably 5 to 30 parts by weight, even more preferably 8 to 25 parts by weight, and particularly preferably 10 to 20 parts by weight, per 100 parts by weight of the polymer component (P).

[0125] In the case of the above-described Form 2, the content ratio of the tackifier resin in the adhesive composition is preferably 1 to 50 parts by weight, more preferably 5 to 30 parts by weight, still more preferably 8 to 25 parts by weight, and particularly preferably 10 to 20 parts by weight with respect to 100 parts by weight of the total amount of the monomer component (m).

[0126] In the case of the above-described Form 3, the content ratio of the tackifier resin in the adhesive composition is preferably 1 to 50 parts by weight, more preferably 5 to 30 parts by weight, still more preferably 8 to 25 parts by weight, and particularly preferably 10 to 20 parts by weight with respect to 100 parts by weight of the total amount of the polymer component (P) and the monomer component (m).

[0127] <A-2-1-5. Crosslinking Agent> The adhesive composition may contain a crosslinking agent. The crosslinking agent may be only one type or two or more types. By including the crosslinking agent in the adhesive composition, the double-sided adhesive tape of the present invention can exhibit excellent oil resistance in addition to excellent impact resistance.

[0128] As the crosslinking agent, any suitable crosslinking agent can be adopted as long as the effects of the present invention are not impaired. Examples of such crosslinking agents include isocyanate-based crosslinking agents and non-isocyanate-based crosslinking agents.

[0129] As the isocyanate crosslinking agent, any suitable isocyanate crosslinking agent can be used as long as it does not impair the effects of the present invention. Examples of such isocyanate crosslinking agents include aromatic diisocyanates, aliphatic diisocyanates, alicyclic diisocyanates, and dimers and trimers of these diisocyanates. Specifically, tolylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, hydrogenated diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, butane-1,4-diisocyanate, 2,2,4-trimethylhex Shark methyl diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, cyclohexane-1,4-diisocyanate, dicyclohexylmethane-4,4-diisocyanate, 1,3-bis(isocyanate-methyl)cyclohexane, methylcyclohexane diisocyanate, m-tetramethylxylylene diisocyanate, etc., as well as their dimers and trimers, and polyphenylmethane polyisocyanate are used. Examples of the above trimers include isocyanurate type, biuret type, and allophanate type.

[0130] Commercially available isocyanate crosslinking agents may be used. Examples of commercially available polyisocyanates include "Takenate 600" from Mitsui Chemicals, "Duranate TPA100" from Asahi Kasei Chemicals, and "Coronate L," "Coronate HL," "Coronate HK," "Coronate HX," and "Coronate 2096" from Nippon Polyurethane Industries, Ltd.

[0131] Examples of non-isocyanate crosslinking agents include epoxy crosslinking agents, oxazoline crosslinking agents, aziridine crosslinking agents, melamine crosslinking agents, carbodiimide crosslinking agents, hydrazine crosslinking agents, amine crosslinking agents, peroxide crosslinking agents, metal chelate crosslinking agents, metal alkoxide crosslinking agents, metal salt crosslinking agents, and silane coupling agents.

[0132] In one preferred embodiment, an epoxy crosslinking agent can be used as a non-isocyanate crosslinking agent. Preferably, the epoxy crosslinking agent is a compound having two or more epoxy groups in one molecule, and more preferably, an epoxy crosslinking agent having three to five epoxy groups in one molecule.

[0133] Specific examples of epoxy crosslinking agents include, for example, N,N,N',N'-tetraglycidyl-m-xylenediamine, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, 1,6-hexanediol diglycidyl ether, polyethylene glycol diglycidyl ether, and polyglycerol polyglycidyl ether. Commercially available epoxy crosslinking agents include, for example, "TETRAD-C" and "TETRAD-X" from Mitsubishi Gas Chemical Company, "Epiclon CR-5L" from DIC Corporation, "Denacol EX-512" from Nagase ChemteX Corporation, and "TEPIC-G" from Nissan Chemical Industries, Ltd.

[0134] In the case of Embodiment 1 described above, the content of the crosslinking agent in the adhesive composition is preferably 0.01 to 10 parts by weight, more preferably 0.1 to 8 parts by weight, even more preferably 0.5 to 7 parts by weight, and particularly preferably 1.5 to 3.5 parts by weight, per 100 parts by weight of the polymer component (P). If the content of the crosslinking agent in the adhesive composition is within the above range, the double-sided adhesive tape of the present invention can exhibit better oil resistance.

[0135] In the case of Embodiment 2 described above, the content of the crosslinking agent in the adhesive composition is preferably 0.01 to 10 parts by weight, more preferably 0.1 to 8 parts by weight, even more preferably 0.5 to 7 parts by weight, and particularly preferably 1.5 to 3.5 parts by weight, based on 100 parts by weight of the total amount of monomer component (m). If the content of the crosslinking agent in the adhesive composition is within the above range, the double-sided adhesive tape of the present invention can exhibit better oil resistance.

[0136] In the case of the above-described Form 3, the content ratio of the crosslinking agent in the adhesive composition is preferably 0.01 parts by weight to 10 parts by weight, more preferably 0.1 parts by weight to 8 parts by weight, still more preferably 0.5 parts by weight to 7 parts by weight, and particularly preferably 1.5 parts by weight to 3.5 parts by weight with respect to 100 parts by weight of the total amount of the polymer component (P) and the monomer component (m). If the content ratio of the crosslinking agent in the adhesive composition is within the above range, the double-sided adhesive tape of the present invention can exhibit more excellent oil resistance.

[0137] In the adhesive composition, an isocyanate-based crosslinking agent and a non-isocyanate-based crosslinking agent (for example, an epoxy-based crosslinking agent) may be used in combination. In this case, in terms of the double-sided adhesive tape of the present invention being able to exhibit more excellent oil resistance, the content ratio of the non-isocyanate-based crosslinking agent in the adhesive composition is preferably 1 / 50 or less, more preferably 1 / 75 or less, still more preferably 1 / 100 or less, and particularly preferably 1 / 150 or less with respect to the content ratio of the isocyanate-based crosslinking agent in the adhesive composition. Also, in terms of the double-sided adhesive tape of the present invention being able to exhibit more excellent oil resistance, the content ratio of the non-isocyanate-based crosslinking agent in the adhesive composition is preferably 1 / 1000 or more, more preferably 1 / 500 or more with respect to the content ratio of the isocyanate-based crosslinking agent in the adhesive composition.

[0138] <A-2-1-6. Rust inhibitor> The adhesive composition may contain a rust inhibitor. The rust inhibitor may be only one kind or two or more kinds. By the adhesive composition containing a rust inhibitor, the double-sided adhesive tape of the present invention can exhibit more excellent oil resistance.

[0139] As the rust inhibitor, any appropriate rust inhibitor can be adopted as long as the effects of the present invention are not impaired. Examples of such a rust inhibitor include azole-based rust inhibitors.

[0140] As an azole-based rust inhibitor, it is preferable to use an azole compound as an active ingredient that is a five-membered ring aromatic compound containing two or more heteroatoms, at least one of which is a nitrogen atom. Examples of such azole compounds include azoles such as imidazole, pyrazole, oxazole, isoxazole, thiazole, isothiazole, serenazole, 1,2,3-triazole, 1,2,4-triazole, 1,2,5-oxadiazole, 1,3,4-oxadiazole, 1,2,3-thiadiazole, 1,2,4-thiadiazole, 1,3,4-thiadiazole, tetrazole, and 1,2,3,4-thiatriazole; derivatives thereof; amine salts thereof; and metal salts thereof.

[0141] Examples of azole derivatives include compounds with structures containing a fused ring of an azole ring and another ring, specifically a benzene ring. Specific examples of azole derivatives include benzimidazole, benzotriazole (i.e., 1,2,3-benzotriazole, which has a structure in which the azole ring and benzene ring of 1,2,3-triazole are fused), benzothiazole, and further derivatives thereof such as alkylbenzotriazoles (e.g., 5-methylbenzotriazole, 5-ethylbenzotriazole, 5-n-propylbenzotriazole, 5-isobutylbenzotriazole, 4-methylbenzotriazole), alkoxybenzotriazoles (e.g., 5-methoxybenzotriazole), alkylaminobenzotriazole, alkylaminobenzotriazole, and alkylaminobenzotriazole. Examples of azole derivatives include minosulfonylbenzotriazole, mercaptobenzotriazole, hydroxybenzotriazole, nitrobenzotriazole (e.g., 4-nitrobenzotriazole), halobenzotriazole (e.g., 5-chlorobenzotriazole), hydroxyalkylbenzotriazole, hydrobenzotriazole, aminobenzotriazole, (substituted aminomethyl)-tolyltriazole, carboxybenzotriazole, N-alkylbenzotriazole, bisbenzotriazole, naphthotriazole, mercaptobenzothiazole, aminobenzothiazole, their amine salts, and their metal salts. Other examples of azole derivatives include azole derivatives with a non-condensed ring structure, such as compounds with substituents on a non-condensed azole ring, like 3-amino-1,2,4-triazole and 5-phenyl-1H-tetrazole.

[0142] Particularly preferred as an azole-based rust inhibitor is a benzotriazole-based rust inhibitor containing a benzotriazole compound as an active ingredient. By using a benzotriazole-based rust inhibitor containing a benzotriazole compound as an active ingredient as the azole-based rust inhibitor, the double-sided adhesive tape of the present invention can exhibit even better oil resistance.

[0143] Examples of benzotriazole compounds include, for instance, 1,2,3-benzotriazole, 5-methylbenzotriazole, 4-methylbenzotriazole, and carboxybenzotriazole.

[0144] The adhesive composition may contain rust inhibitors other than azole-based rust inhibitors. The non-azole rust inhibitors may be one type or two or more types. Specific examples of such non-azole rust inhibitors include, for example, amine compounds, nitrites, ammonium benzoate, ammonium phthalate, ammonium stearate, ammonium palmitate, ammonium oleate, ammonium carbonate, dicyclohexylamine benzoate, urea, urotropin, thiourea, phenyl carbamate, and cyclohexylammonium-N-cyclohexylcarbamate (CHC). Examples of amine compounds include, for example, 2-amino-2-methyl-1-propanol, monoethanolamine, monoisopropanolamine, diethylethanolamine, hydroxyl group-containing amine compounds such as ammonia and ammonia water; cyclic amines such as morpholine; cyclic alkylamine compounds such as cyclohexylamine; and linear alkylamines such as 3-methoxypropylamine. Examples of nitrites include dicyclohexylammonium nitride (DICHAN), diisopropylammonium nitride (DIPAN), sodium nitrite, potassium nitrite, and calcium nitrite.

[0145] In the case of Embodiment 1 described above, the content ratio of the rust inhibitor in the adhesive composition is preferably 0.01 to 7 parts by weight, more preferably 0.05 to 6 parts by weight, even more preferably 0.1 to 5 parts by weight, particularly preferably 0.3 to 4 parts by weight, and most preferably 0.5 to 3 parts by weight, per 100 parts by weight of the polymer component (P).

[0146] In the case of Embodiment 2 described above, the content ratio of the rust inhibitor in the adhesive composition is preferably 0.01 to 7 parts by weight, more preferably 0.05 to 6 parts by weight, even more preferably 0.1 to 5 parts by weight, particularly preferably 0.3 to 4 parts by weight, and most preferably 0.5 to 3 parts by weight, based on 100 parts by weight of the total amount of monomer component (m).

[0147] In the case of Embodiment 3 described above, the content ratio of the rust inhibitor in the adhesive composition is preferably 0.01 to 7 parts by weight, more preferably 0.05 to 6 parts by weight, even more preferably 0.1 to 5 parts by weight, particularly preferably 0.3 to 4 parts by weight, and most preferably 0.5 to 3 parts by weight, based on 100 parts by weight of the total amount of polymer component (P) and monomer component (m).

[0148] ≪B. Method for manufacturing double-sided adhesive tape≫ The double-sided adhesive tape of the present invention can be manufactured by any suitable method, provided that the effects of the present invention are not impaired. Such a method includes, for example, preparing each adhesive layer separately and bonding them together by any suitable method. For example, if the double-sided adhesive tape of the present invention consists of three adhesive layers, one method would be to bond the remaining two adhesive layers to both sides of one adhesive layer. For bonding, for example, a laminator may be used. Furthermore, after bonding, aging may be performed at any suitable temperature for any suitable time, if necessary.

[0149] ≪C. Typical uses of double-sided adhesive tape≫ The double-sided adhesive tape of the present invention can be used in any suitable application, as long as the effects of the present invention are not impaired. Typical examples of such applications include mobile devices. Typical examples of mobile devices include mobile electronic devices.

[0150] Applications in mobile devices include, for example, fixing the display unit of mobile electronic devices, fixing protective components for the display unit of mobile electronic devices, fixing key module components of mobile phones (smartphones, etc.), fixing decorative panels of mobile televisions, fixing battery packs of mobile computers, waterproofing lenses of digital video cameras, fixing touch sensors, fixing vibration generators, fixing cameras, fixing batteries, fixing narrow components, use as a sealant, and fixing gaskets such as sealants.

[0151] Preferably, applications in mobile devices include fixing components included in mobile devices (preferably mobile electronic devices), and more preferably, fixing a display unit or display unit protective member included in a mobile device (preferably mobile electronic device) to a housing.

[0152] The double-sided adhesive tape of the present invention can be used in mobile electronic devices having a display unit, such as a liquid crystal display device. For example, the double-sided adhesive tape of the present invention is suitable for joining a display unit, such as a liquid crystal display device, or a display unit protective member to a housing in such mobile electronic devices.

[0153] The above-mentioned display protection member is typically a member having a region that exhibits light transmission in the thickness direction (hereinafter also referred to as a "light-transmitting member"), and is sometimes called a lens. Here, in this specification, "lens" is a concept that encompasses both those that exhibit light refraction and those that do not. In other words, "lens" in this specification also includes light-transmitting members that do not exhibit refraction, such as protective panels that simply protect the display of mobile electronic devices. Such protective panels can also be understood as light-transmitting display protection members or display cover members. If the material of such a protective panel is glass, the protective panel may also be called a "cover glass". However, the material of such protective panels and lenses is not limited to glass; any material capable of exhibiting light transmission is acceptable.

[0154] Furthermore, in this specification, "mobile electronic device" may include any suitable electronic device that can be carried and used. Here, "portable" means not merely being able to carry, but having a level of portability that allows an individual (a typical adult) to carry it relatively easily. Examples of "mobile electronic devices" as used herein include mobile phones, smartphones, tablet PCs, and notebook PCs. Such mobile electronic devices may also be so-called wearable devices (e.g., wristband-type devices such as watches, head-mounted devices such as glasses, etc.). Specifically, such mobile electronic devices include, for example, telephones, watches, cameras, glasses, personal computers, other information terminals, health management tools such as blood pressure monitors, pulse meters, and pedometers, music players, video players, and devices with one or more functions such as recording and video recording. [Examples]

[0155] The present invention will be specifically described below with reference to examples, but the present invention is not limited in any way to these examples. The test and evaluation methods in the examples are as follows. When "parts" is written, it means "parts by weight" unless otherwise specified, and when "%" is written, it means "percent by weight" unless otherwise specified.

[0156] <Weight average molecular weight> The weight-average molecular weight was determined from the value obtained by GPC (gel permeation chromatography) on a standard polystyrene basis. The GPC instrument used was model "HLC-8320GPC" (column: TSKgelGMH-H(S), manufactured by Tosoh Corporation).

[0157] <Impact Resistance> Double-sided adhesive tape sandwiched between separators was punched out in a 2mm wide, 24.5mm square frame shape to serve as the evaluation sample. The evaluation sample was placed between a 2mm thick, 50mm x 50mm square stainless steel plate with a hole in the center and a square stainless steel plate (25mm square outer diameter, 3mm thick), and pressed together uniformly by gravity (62N x 10 seconds). After that, it was left to stand at 50°C for 2 hours, removed, and returned to 23°C to be used as the test specimen. A cylindrical measuring stand with a length of 50mm, an outer diameter of 49mm, and an inner diameter of 43mm was placed on the base of a DuPont impact tester (manufactured by Toyo Seiki Seisakusho Co., Ltd.), and the test specimen was placed on top of it with the square stainless steel plate facing downwards. A stainless steel impact pin with a tip radius of 3.1 mm was placed on the test specimen, and the weight of the drop weight and the drop height were varied in 50 mm increments from 50 mm to 500 mm with a 100 g weight, from 350 mm to 500 mm with a 150 g weight, from 400 mm to 500 mm with a 200 g weight, and from 350 mm to 500 mm with a 300 g weight, so that the energy increased until delamination occurred. At this time, tests were not conducted for energy levels that had already been evaluated, and the load and height were set so that the amount of energy did not overlap. The energy up to the point of delamination was then calculated as load × height and the result was obtained.

[0158] [Manufacturing Example 1]: Manufacturing of adhesive layer (1) In a reaction vessel equipped with a stirrer, thermometer, nitrogen gas inlet tube, reflux condenser, and dropping funnel, 95 parts butyl acrylate and 5 parts acrylic acid as monomer components, and 233 parts ethyl acetate as polymerization solvent were charged, and the mixture was stirred for 2 hours while introducing nitrogen gas. After removing oxygen from the polymerization system in this way, 0.2 parts 2,2'-azobisisobutyronitrile was added as a polymerization initiator, and solution polymerization was carried out at 60°C for 8 hours to obtain a solution of acrylic polymer. The weight-average molecular weight of this acrylic polymer was 700,000. To the obtained acrylic polymer solution, per 100 parts of the acrylic polymer contained in the solution, 20 parts of terpene phenol resin (product name "YS Polystar T-115", softening point approximately 115°C, hydroxyl value 30-60 mg KOH / g, manufactured by Yasuhara Chemical Co., Ltd.) as a tackifying resin, 3 parts of isocyanate crosslinking agent (product name "Coronate L", 75% ethyl acetate solution of trimethylolpropane / tolylene diisocyanate trimer adduct, manufactured by Tosoh Corporation) as a crosslinking agent, and epoxy crosslinking agent (product name " 0.02 parts of TETRAD-C, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane (manufactured by Mitsubishi Gas Chemical Co., Ltd.), 6 parts of black pigment (product name ATDN101 Black, manufactured by Dainichi Seika Kogyo Co., Ltd.), and 5 parts of organic hollow filler (product name Matsumoto Microsphere MFL-81GCA, manufactured by Matsumoto Oil & Fat Co., Ltd., specific gravity = 0.23, heat resistance = 130℃, average particle size = 20 μm) were added and stirred to prepare adhesive composition (1). An adhesive composition (1) was applied to the release surface of a 38 μm thick polyester release liner (product name "Diafoil MRF", manufactured by Mitsubishi Polyester Corporation), and dried at 100°C for 2 minutes to form an adhesive layer (1) with a thickness of 100 μm.

[0159] [Manufacturing Example 2]: Manufacturing of the adhesive layer (2) Except for changing the amount of organic hollow filler to 2 parts, the procedure was carried out in the same manner as in Production Example 1, and an adhesive layer (2) with a thickness of 100 μm was formed.

[0160] [Manufacturing Example 3]: Manufacturing of the adhesive layer (3) Except for changing the amount of organic hollow filler to 0.5 parts, the procedure was carried out in the same manner as in Production Example 1, and an adhesive layer (3) with a thickness of 100 μm was formed.

[0161] [Manufacturing Example 4] Manufacturing of the adhesive layer (4) Except for changing the amount of organic hollow filler to 10 parts, the procedure was carried out in the same manner as in Production Example 1, and an adhesive layer (4) with a thickness of 100 μm was formed.

[0162] [Manufacturing Example 5] Manufacturing of the adhesive layer (5) Except for replacing the organic hollow filler with acrylonitrile hollow filler (product name "Matsumoto Microsphere MFL-HD30CA", manufactured by Matsumoto Oil & Fat Co., Ltd., specific gravity = 0.14, heat resistance = 140℃, average particle size = 30μm) in part, the same procedure as in Manufacturing Example 1 was followed to form an adhesive layer (5) with a thickness of 100μm.

[0163] [Manufacturing Example 6] Manufacturing of the adhesive layer (6) Except for changing the amount of organic hollow filler to 5 parts, the procedure was carried out in the same manner as in Production Example 5, and an adhesive layer (6) with a thickness of 100 μm was formed.

[0164] [Manufacturing Example 7] Manufacturing of the adhesive layer (7) Except for changing the amount of organic hollow filler to 10 parts, the procedure was carried out in the same manner as in Production Example 5 to form an adhesive layer (7) with a thickness of 100 μm.

[0165] [Manufacturing Example 8] Manufacturing of the adhesive layer (8) Except for replacing the organic hollow filler with acrylonitrile hollow filler (product name "Matsumoto Microsphere MFL-100MCA", manufactured by Matsumoto Oil & Fat Co., Ltd., specific gravity = 0.12, heat resistance = 155℃, average particle size = 60μm) in part, the same procedure as in Manufacturing Example 1 was followed to form an adhesive layer (5) with a thickness of 100μm.

[0166] [Manufacturing Example 9] Manufacturing of the adhesive layer (9) Except for changing the amount of organic hollow filler to 3 parts, the procedure was carried out in the same manner as in Production Example 8, and an adhesive layer (9) with a thickness of 100 μm was formed.

[0167] [Manufacturing Example 10] Manufacturing of adhesive layer (10) Except for changing the amount of organic hollow filler to 5 parts, the procedure was carried out in the same manner as in Production Example 8 to form an adhesive layer (10) with a thickness of 100 μm.

[0168] [Manufacturing Example 11] Manufacturing of the adhesive layer (11) Except for replacing the organic hollow filler with 0.1 parts of acrylonitrile hollow filler (product name "Matsumoto Microsphere FN-80SDE", manufactured by Matsumoto Oil & Fat Co., Ltd., specific gravity = 0.025, heat resistance = 140℃, average particle size = 30μm), the same procedure as in Manufacturing Example 1 was followed to form an adhesive layer (11) with a thickness of 100μm.

[0169] [Manufacturing Example 12] Manufacturing of the adhesive layer (12) Except for changing the amount of organic hollow filler to 2 parts, the procedure was carried out in the same manner as in Production Example 11 to form an adhesive layer (12) with a thickness of 100 μm.

[0170] [Manufacturing Example 13] Manufacturing of the adhesive layer (13) Except for not using a hollow filler and setting the thickness after drying to 200 μm, the procedure was the same as in Production Example 1 to form an adhesive layer (13) with a thickness of 200 μm.

[0171] [Manufacturing Example 14] Manufacturing of the adhesive layer (14) Except for not using a hollow filler and setting the thickness after drying to 85 μm, the procedure was the same as in Production Example 1 to form an adhesive layer (14) with a thickness of 85 μm.

[0172] [Example 1] Two adhesive layers (1) obtained in Manufacturing Example 1 were bonded together, with the adhesive layer surfaces without release liners facing each other. The resulting structure was passed through a laminator (0.3 MPa, speed 0.5 m / min) once at room temperature, and then aged in a 50°C oven for one day. After that, the release liners were peeled off. In this way, a double-sided adhesive tape (1) with a total thickness of 200 μm (composition: adhesive layer (1) / adhesive layer (1)) was obtained, as shown in Table 1. The evaluation results are shown in Table 1. Furthermore, Figure 2 shows a photograph of the cross-section of the obtained double-sided adhesive tape (1) taken with a scanning electron microscope (Hitachi High-Technologies Corporation S-3400N).

[0173] [Example 2] Two adhesive layers (2) obtained in Manufacturing Example 2 were bonded together, with the adhesive layer surfaces without release liners facing each other. The resulting structure was passed through a laminator (0.3 MPa, speed 0.5 m / min) once at room temperature, and then aged in a 50°C oven for one day. After that, the release liners were peeled off. In this way, a double-sided adhesive tape (2) with a total thickness of 200 μm (composition: adhesive layer (2) / adhesive layer (2)) was obtained, as shown in Table 1. The evaluation results are shown in Table 1.

[0174] [Example 3] Two adhesive layers (3) obtained in Manufacturing Example 3 were bonded together, with the adhesive layer surfaces without release liners facing each other. The resulting structure was passed through a laminator (0.3 MPa, speed 0.5 m / min) once at room temperature, and then aged in a 50°C oven for one day. After that, the release liners were peeled off. In this way, a double-sided adhesive tape (3) with a total thickness of 200 μm (composition: adhesive layer (3) / adhesive layer (3)) was obtained, as shown in Table 1. The evaluation results are shown in Table 1.

[0175] [Example 4] Two adhesive layers (4) obtained in Manufacturing Example 4 were bonded together, with the adhesive layer surfaces without release liners facing each other. The resulting structure was passed through a laminator (0.3 MPa, speed 0.5 m / min) once at room temperature, and then aged in a 50°C oven for one day. After that, the release liners were peeled off. In this way, a double-sided adhesive tape (4) with a total thickness of 200 μm (composition: adhesive layer (4) / adhesive layer (4)) was obtained, as shown in Table 1. The evaluation results are shown in Table 1.

[0176] [Example 5] Two adhesive layers (5) obtained in Manufacturing Example 5 were bonded together, with the adhesive layer surfaces without release liners facing each other. The resulting structure was passed through a laminator (0.3 MPa, speed 0.5 m / min) once at room temperature, and then aged in a 50°C oven for one day. After that, the release liners were peeled off. In this way, a double-sided adhesive tape (5) with a total thickness of 200 μm (composition: adhesive layer (5) / adhesive layer (5)) was obtained, as shown in Table 1. The evaluation results are shown in Table 1.

[0177] [Example 6] Two adhesive layers (6) obtained in Manufacturing Example 6 were bonded together, with the adhesive layer surfaces without release liners facing each other. The resulting structure was passed through a laminator (0.3 MPa, speed 0.5 m / min) once at room temperature, and then aged in a 50°C oven for one day. After that, the release liners were peeled off. In this way, a double-sided adhesive tape (6) with a total thickness of 200 μm (composition: adhesive layer (6) / adhesive layer (6)) was obtained, as shown in Table 1. The evaluation results are shown in Table 1.

[0178] [Example 7] Two adhesive layers (7) obtained in Manufacturing Example 7 were bonded together, with the adhesive layer surfaces without release liners facing each other. The resulting structure was passed through a laminator (0.3 MPa, speed 0.5 m / min) once at room temperature, and then aged in a 50°C oven for one day. After that, the release liners were peeled off. In this way, a double-sided adhesive tape (7) with a total thickness of 200 μm (composition: adhesive layer (7) / adhesive layer (7)) was obtained, as shown in Table 1. The evaluation results are shown in Table 1.

[0179] [Example 8] Two adhesive layers (8) obtained in Manufacturing Example 8 were bonded together, with the adhesive layer surfaces without release liners facing each other. The resulting structure was passed through a laminator (0.3 MPa, speed 0.5 m / min) once at room temperature, and then aged in a 50°C oven for one day. After that, the release liners were peeled off. In this way, a double-sided adhesive tape (8) with a total thickness of 200 μm (composition: adhesive layer (8) / adhesive layer (8)) was obtained, as shown in Table 1. The evaluation results are shown in Table 1.

[0180] [Example 9] Two adhesive layers (9) obtained in Manufacturing Example 9 were bonded together, with the adhesive layer surfaces without release liners facing each other. The resulting structure was passed through a laminator (0.3 MPa, speed 0.5 m / min) once at room temperature, and then aged in a 50°C oven for one day. After that, the release liners were peeled off. In this way, a double-sided adhesive tape (9) with a total thickness of 200 μm (composition: adhesive layer (9) / adhesive layer (9)) was obtained, as shown in Table 1. The evaluation results are shown in Table 1.

[0181] [Example 10] Two adhesive layers (10) obtained in Manufacturing Example 10 were bonded together, with the adhesive layer surfaces without release liners facing each other. The resulting structure was passed through a laminator (0.3 MPa, speed 0.5 m / min) once at room temperature, and then aged in a 50°C oven for one day. After that, the release liners were peeled off. In this way, a double-sided adhesive tape (10) with a total thickness of 200 μm (composition: adhesive layer (10) / adhesive layer (10)) was obtained, as shown in Table 1. The evaluation results are shown in Table 1.

[0182] [Example 11] Two adhesive layers (11) obtained in Manufacturing Example 11 were bonded together, with the adhesive layer surfaces without release liners facing each other. The resulting structure was passed through a laminator (0.3 MPa, speed 0.5 m / min) once at room temperature, and then aged in a 50°C oven for one day. After that, the release liners were peeled off. In this way, a double-sided adhesive tape (11) with a total thickness of 200 μm (composition: adhesive layer (11) / adhesive layer (11)) was obtained, as shown in Table 1. The evaluation results are shown in Table 1.

[0183] [Example 12] Two adhesive layers (12) obtained in Manufacturing Example 12 were bonded together, with the adhesive layer surfaces that did not have a release liner attached facing each other. The resulting structure was passed through a laminator (0.3 MPa, speed 0.5 m / min) once at room temperature, and then aged in a 50°C oven for one day. After that, the release liner was peeled off. In this way, a double-sided adhesive tape (12) with a total thickness of 200 μm (composition: adhesive layer (12) / adhesive layer (12)) was obtained, as shown in Table 1. The evaluation results are shown in Table 1.

[0184] [Comparative Example 1] The release liner was peeled off the adhesive layer (16) obtained in manufacturing example 16, and a single-layer double-sided adhesive tape (C1) (composition: adhesive layer (16)) with a total thickness of 200 μm was obtained, as shown in Table 1. The evaluation results are shown in Table 1.

[0185] [Comparative Example 2] The release liner was peeled off the adhesive layer (17) obtained in manufacturing example 17, and a single-layer double-sided adhesive tape (C2) (composition: adhesive layer (17)) with a total thickness of 85 μm was obtained, as shown in Table 1. The evaluation results are shown in Table 1.

[0186] [Table 1] [Industrial applicability]

[0187] The double-sided adhesive tape of the present invention can be suitably used inside mobile devices and the like. [Explanation of symbols]

[0188] Double-sided adhesive tape 100 Adhesive layer 10a Adhesive layer 10b Adhesive layer 10c

Claims

1. A double-sided adhesive tape consisting only of an adhesive layer, The adhesive layer laminate is formed by laminating n or more adhesive layers. n is an integer of 2 or more, and the adhesive layer laminate has (n-1) interfaces. The adhesive layer is formed from an adhesive composition, The adhesive composition comprises an organic hollow filler, The adhesive composition contains an acrylic polymer as the base polymer, The acrylic polymer is formed by polymerization of monomer components (m), The monomer component (m) contains 90% to 100% by weight of n-butyl (meth)acrylate. The specific gravity of the aforementioned organic hollow filler is 0.05 to 1.

00. Double-sided adhesive tape used to secure components included in mobile devices.

2. The double-sided adhesive tape according to claim 1, wherein the average particle size of the organic hollow filler is 5 μm to 70 μm.

3. The double-sided adhesive tape according to claim 2, wherein the organic hollow filler is an acrylonitrile hollow filler.

4. A double-sided adhesive tape according to any one of claims 1 to 3, wherein the thickness is 100 μm or more.

5. A double-sided adhesive tape according to any one of claims 1 to 4, used for fixing a display unit or display unit protective member included in a mobile device to a housing.

Images