Double-sided adhesive sheet for application to the skin

Abstract

To provide a double-sided adhesive sheet for skin patch having excellent adhesion to an attachment object.SOLUTION: A double-sided adhesive sheet for skin patch 1 includes a substrate layer 2 and adhesive layers 3 and 4 respectively disposed on both surfaces of the substrate layer 2. Surface free energy of one adhesive surface 3a at a temperature of 23°C and relative humidity of 50% is less than 20 mJ / m2. The other adhesive surface 4a is a side attached to a skin. Rupture stress at least in one direction of the double-sided adhesive sheet for skin patch 1 is preferably 0.8 N / mm2 or more.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a double-sided pressure-sensitive adhesive sheet that is applied to the skin. [Background technology]

[0002] Adhesive sheets for application to the skin are often used in the fields of medicine, sports, beauty, etc. Adhesive sheets for application to the skin are required to have excellent adhesion to the skin and safety. Adhesive sheets for application to the skin are known, for example, as disclosed in Cited Documents 1 to 3. For example, Cited Document 3 discloses a gel sheet used for measuring electroencephalograms. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-128453 [Patent Document 2] Japanese Patent Publication No. 2020-128454 [Patent Document 3] Patent Publication No. 2021-24907 Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, for healthcare purposes, such as for determining the health status of the human body, electronic devices such as various measuring instruments are sometimes attached to the skin of the human body. When attaching patches of electronic devices, etc. to the skin, it is considered to use double-sided pressure-sensitive adhesive sheets. The double-sided pressure-sensitive adhesive sheets used to attach such patches to the skin are required to have excellent adhesion to the patches.

[0005] The present invention was conceived under these circumstances, and its object is to provide a double-sided pressure-sensitive adhesive sheet for application to the skin that has excellent adhesion to patches. [Means for solving the problem]

[0006] As a result of extensive research to achieve the above object, the present inventors have found that a double-sided PSA sheet for application to skin, which is provided with a base layer and in which the surface free energy of the adhesive surface facing the patch is within a specific range, exhibits excellent adhesion to the patch. The present invention was completed based on these findings.

[0007] That is, the present invention provides a film comprising a substrate layer and pressure-sensitive adhesive layers provided on both sides of the substrate layer, the surface free energy of one of the adhesive surfaces being 20 mJ / m at a temperature of 23°C and a relative humidity of 50%. 2 The double-sided pressure-sensitive adhesive sheet for application to the skin is provided, wherein the thickness of the double-sided pressure-sensitive adhesive sheet is less than 1 mm, and the other adhesive surface is the side to be applied to the skin.

[0008] The double-sided pressure-sensitive adhesive sheet for application to the skin has a breaking stress in at least one direction of 0.8 N / mm 2 It is preferable that this is equal to or greater than this.

[0009] The above double-sided pressure-sensitive adhesive sheet for application to skin preferably has a Young's modulus in at least one direction of 50 MPa or less.

[0010] The 180° peel strength of the one adhesive surface against a silicone resin substrate, measured at a temperature of 23° C. and a peel rate of 50 mm / min, is preferably 2 N / 20 mm or more.

[0011] The double-sided pressure-sensitive adhesive sheet for application to skin preferably has an average total light transmittance of 40% or more in the wavelength range of 400 to 700 nm and an average total light transmittance of 40% or more in the wavelength range of 2000 to 2500 nm, as measured in accordance with JIS K7136-1.

[0012] The surface free energy of the other adhesive surface is 20 to 50 mJ / m 2 It is preferable that:

[0013] The double-sided pressure-sensitive adhesive sheet for application to skin preferably has a total thickness of less than 1000 μm.

[0014] The pressure-sensitive adhesive layer providing the one adhesive surface and the pressure-sensitive adhesive layer providing the other adhesive surface preferably contain different types of base polymers.

[0015] The pressure-sensitive adhesive layer providing the other adhesive surface is preferably an acrylic pressure-sensitive adhesive layer containing an acrylic polymer as a base polymer.

[0016] The double-sided pressure-sensitive adhesive sheet for application to skin is preferably used for application in which an electronic device is applied to human skin.

[0017] The electronic device is preferably a flexible device.

[0018] The present invention also provides an electronic device comprising the above double-sided pressure-sensitive adhesive sheet for application to skin. [Effects of the Invention]

[0019] The double-sided pressure-sensitive adhesive sheet for application to skin of the present invention has excellent adhesion to patches. [Brief explanation of the drawings]

[0020] [Figure 1] 1 is a cross-sectional view of a double-sided pressure-sensitive adhesive sheet for application to skin according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0021] [Double-sided adhesive sheet for application to the skin] The double-sided pressure-sensitive adhesive sheet for application to skin of the present invention is a double-sided pressure-sensitive adhesive sheet that is used by applying one adhesive surface to a patch and the other adhesive surface to the skin. In this specification, the adhesive surface that is applied to the patch may be referred to as "adhesive surface A," and the adhesive surface that is applied to the skin may be referred to as "adhesive surface B." Furthermore, the adhesive layer that provides adhesive surface A may be referred to as "adhesive layer A," and the adhesive layer that provides adhesive surface B may be referred to as "adhesive layer B."

[0022] The surface free energy of one of the adhesive surfaces (adhesive surface A) of the double-sided adhesive sheet for application to skin at a temperature of 23°C and a relative humidity of 50% is 20 mJ / m 2 less than 18 mJ / m 2 The surface free energy is 20 mJ / m or less. 2 When the surface tension is less than 100%, the adhesive surface A has excellent adhesion to the object to be attached (particularly, the object to be attached has low surface free energy).

[0023] The surface free energy of the other adhesive surface (adhesive surface B) at a temperature of 23°C and a relative humidity of 50% is 20 to 50 mJ / m 2 is preferable, and more preferably 20.5 to 40 mJ / m 2 When the surface free energy is within the above range, adhesive surface B has better adhesion to the skin.

[0024] The surface free energy γ of the adhesive surface is expressed by the following formula: γ=γ d +γ p +γ h where γ in the above formula is the value represented by d , γ p and γ hThe γ's represent the dispersion component, polar component, and hydrogen bond component of the surface free energy, respectively. The surface free energy γ of the adhesive surface can be determined from the contact angle of each probe liquid using water, diiodomethane, and 1-bromonaphthalene according to the Kitazaki-Hata method (Journal of the Japan Adhesion Association, Vol. 8, No. 3, 1972, pp. 131-141). The contact angle can be measured using a commercially available contact angle meter. A contact angle meter such as the "DMo-701" manufactured by Kyowa Interface Science Co., Ltd. can be used. The sessile drop method is used to measure the contact angle from the shape of the droplet 1000 ms after it has landed on the surface. A similar method is also used in the examples described below.

[0025] The 180° peel strength of adhesive surface A against a silicone resin substrate, measured at a temperature of 23°C and a peel rate of 50 mm / min, is preferably 2 N / 20 mm or more, more preferably 2.5 N / 20 mm or more, and even more preferably 4 N / 20 mm or more. A peel strength of 2 N / 20 mm or more indicates excellent adhesion of adhesive surface A to the object to be affixed.

[0026] The double-sided pressure-sensitive adhesive sheet for application to skin comprises at least a base layer and pressure-sensitive adhesive layers provided on both sides of the base layer. Specifically, the double-sided pressure-sensitive adhesive sheet comprises at least a base layer, a pressure-sensitive adhesive layer providing pressure-sensitive adhesive surface A, and a pressure-sensitive adhesive layer providing pressure-sensitive adhesive surface B.

[0027] The adhesive layer provided on the side providing adhesive surface A and the adhesive layer provided on the side providing adhesive surface B may each be a single layer or multiple layers. The multiple adhesive layers provided on the double-sided adhesive sheet for application to skin may be the same adhesive layer, or may be adhesive layers with different compositions, thicknesses, physical properties, etc.

[0028] The pressure-sensitive adhesive layer A and the pressure-sensitive adhesive layer B may be the same pressure-sensitive adhesive layer, or may be pressure-sensitive adhesive layers that differ in thickness, physical properties, component composition, etc. In particular, the pressure-sensitive adhesive layer A and the pressure-sensitive adhesive layer B are preferably pressure-sensitive adhesive layers that differ in component composition. Specific examples of different component compositions include differences in the type of base polymer, the composition of the monomer components that make up the base polymer (such as the type and proportion of constituent units), and the composition of components other than the base polymer.

[0029] Figure 1 is a cross-sectional schematic diagram showing one embodiment of the double-sided pressure-sensitive adhesive sheet of the present invention. As shown in Figure 1, double-sided pressure-sensitive adhesive sheet 1 for application to skin comprises a base layer 2, an adhesive layer (adhesive layer A) 3 provided on one side of base layer 2, and an adhesive layer (adhesive layer B) 4 provided on the other side of base layer 2. Adhesive layer 3 has adhesive surface A (3a) that is attached to a patch, and adhesive layer 4 has adhesive surface B (4a) that is attached to the skin. Adhesive layers 3 and 4 are adhesive layers with different component compositions.

[0030] (base material layer) The substrate layer is an element that functions as a support in the double-sided pressure-sensitive adhesive sheet for application to skin. By providing the substrate layer, the double-sided pressure-sensitive adhesive sheet for skin has excellent handleability, and for example, the patch can be easily peeled off from the skin. The substrate layer may be a single layer or a laminate of substrates of the same or different types.

[0031] Examples of the resin constituting the substrate layer include polyolefin resins such as polyethylene-based resins (e.g., low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, high-density polyethylene, and very low-density polyethylene), polypropylene-based resins (e.g., random copolymer polypropylene, block copolymer polypropylene, and homopolypropylene), polybutene, polymethylpentene, ethylene-vinyl acetate copolymer (EVA), ionomers, ethylene-(meth)acrylic acid copolymers, ethylene-(meth)acrylic acid ester (random and alternating) copolymers, ethylene-butene copolymers, and ethylene-hexene copolymers; and ether-based polyurethanes. Examples of suitable resins include polyurethanes such as tan, ester-based polyurethane, and carbonate-based polyurethane; polyesters such as polyethylene terephthalate (PET), polyethylene naphthalate, and polybutylene terephthalate (PBT); polycarbonate; polyimide; polyether ether ketone; polyetherimide; polyamides such as aramid and wholly aromatic polyamide; polyphenyl sulfide; fluororesin; polyvinyl chloride; polyvinylidene chloride; cellulose resins such as triacetyl cellulose (TAC); silicone resins; acrylic resins such as polymethyl methacrylate (PMMA); polyvinyl acetate; polysulfone; and polyarylates. One or more of the above resins may be used. Note that, in this specification, the base layer does not include a release liner (separator) that is peeled off when the double-sided pressure-sensitive adhesive sheet is used (applied).

[0032] Examples of the substrate layer include plastic substrates (e.g., plastic films), porous materials such as paper, cloth, and nonwoven fabrics, nets, foam sheets, etc. Specific examples of the substrate layer include polystyrene-based thermoplastic elastomer films, plastic films such as nylon, polyester, polyethylene, polypropylene, and polyurethane, woven fabrics, nonwoven fabrics, knitted fabrics, and paper made of synthetic or natural organic polymers such as cellulose, and laminates of two or more of these (e.g., laminates of cloths or papers, laminates of films and cloths, and laminates of plastic films).

[0033] As the substrate layer, nonwoven fabrics and plastic substrates are preferred from the viewpoint of excellent transparency. As the plastic substrate, polyurethane-based substrates, polypropylene-based substrates, polyethylene-based substrates, ethylene-vinyl acetate-based substrates, and silicone-based substrates are more preferred. In particular, polyurethane-based films are preferred from the viewpoint of flexibility (skin conformity), appropriate moisture permeability, tensile strength, etc., and polyester-based polyurethane films and polyether-based polyurethane films are particularly preferred. Excellent flexibility means that the flexible device as a patch will have excellent conformity to the movement of the skin when attached to the skin.

[0034] The substrate layer may contain various additives such as fillers (inorganic fillers, organic fillers, etc.), colorants (pigments or dyes), dispersants (surfactants, etc.), antioxidants, antioxidants, UV absorbers, antistatic agents, lubricants, plasticizers, etc. The blending ratio of the various additives is about less than 30% by weight (e.g., less than 20% by weight, typically less than 10% by weight) relative to 100% by weight of the total weight of the substrate layer.

[0035] The substrate layer may include an auxiliary layer, such as a colored layer, an undercoat layer, or an antistatic layer, provided on the surface of the substrate layer.

[0036] The surface of the substrate layer may be subjected to surface treatments such as physical treatments such as corona discharge treatment, plasma treatment, sand matting treatment, ozone exposure treatment, flame exposure treatment, high-voltage shock exposure treatment, and ionizing radiation treatment; chemical treatments such as chromic acid treatment; and adhesion-enhancing treatments using a coating agent (primer), for the purpose of improving adhesion and retention with the pressure-sensitive adhesive layer. The surface treatment for improving adhesion is preferably applied to the entire surface of the substrate layer.

[0037] The thickness of the substrate layer is preferably 500 μm or less, more preferably 250 μm or less, and even more preferably 50 μm or less, from the viewpoint of superior flexibility. The thickness of the substrate layer is preferably 1 μm or more, more preferably 5 μm or more, from the viewpoint of superior support function and superior handleability.

[0038] When using fabrics such as woven fabrics or nonwoven fabrics or paper as the base layer, the basis weight is 8 to 200 g / m 2 It is preferable to use a material of this order.

[0039] (Adhesive layer) The double-sided pressure-sensitive adhesive sheet for application to skin comprises at least a pressure-sensitive adhesive layer A and a pressure-sensitive adhesive layer B. The double-sided pressure-sensitive adhesive sheet for application to skin may comprise a pressure-sensitive adhesive layer other than the pressure-sensitive adhesive layer A and the pressure-sensitive adhesive layer B between the base layer and the pressure-sensitive adhesive layer A or the pressure-sensitive adhesive layer B.

[0040] The adhesive constituting each adhesive layer of the double-sided adhesive sheet for application to skin is not particularly limited, and examples thereof include acrylic adhesives, rubber adhesives (natural rubber, synthetic rubber, mixtures thereof, etc.), silicone adhesives, polyester adhesives, urethane adhesives, polyether adhesives, polyamide adhesives, fluorine adhesives, etc. One type of adhesive may be used alone, or two or more types may be used.

[0041] <Adhesive layer A> A silicone-based pressure-sensitive adhesive is preferred as the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer A, from the viewpoint of easily designing a pressure-sensitive adhesive layer having low surface free energy. That is, the pressure-sensitive adhesive layer A is preferably a silicone-based pressure-sensitive adhesive layer composed of a silicone-based pressure-sensitive adhesive.

[0042] The silicone-based adhesive is not particularly limited and can be appropriately selected from known or commonly used silicone-based adhesives. Examples of the silicone-based adhesive include peroxide-crosslinked silicone-based adhesives (peroxide-cured silicone-based adhesives), addition-type silicone-based adhesives, and condensation-type silicone-based adhesives. Among these, addition reaction-type silicone-based adhesives are preferred. The silicone-based adhesive may be either a one-component type or a two-component type. One type of the silicone-based adhesive may be used alone, or two or more types may be used.

[0043] The addition type silicone-based pressure-sensitive adhesive is generally a pressure-sensitive adhesive that generates a silicone-based polymer by addition reaction (hydrosilylation reaction) between an organopolysiloxane having an alkenyl group such as a vinyl group on a silicon atom and an organopolysiloxane having a hydrosilyl group using a platinum compound catalyst such as chloroplatinic acid. The peroxide-curing type silicone-based pressure-sensitive adhesive is generally a pressure-sensitive adhesive that generates a silicone-based polymer by curing (crosslinking) an organopolysiloxane with a peroxide. Meanwhile, the condensation type silicone-based pressure-sensitive adhesive is generally a pressure-sensitive adhesive that generates a silicone-based polymer by dehydration or dealcoholization reaction between polyorganosiloxanes having hydrolyzable silyl groups such as silanol groups or alkoxysilyl groups at the terminals.

[0044] The silicone-based pressure-sensitive adhesive may be, for example, a silicone-based pressure-sensitive adhesive composition containing a silicone rubber and a silicone resin. The silicone-based pressure-sensitive adhesive may further contain additives such as a crosslinking agent, a catalyst (curing agent), a filler, a plasticizer, an antioxidant, an antistatic agent, and a colorant (pigment, dye, etc.) as needed.

[0045] The silicone rubber is not particularly limited as long as it contains a silicone-based rubber component, but for example, an organopolysiloxane having dimethylsiloxane, methylphenylsiloxane, or the like as its main structural unit can be used. Depending on the type of reaction, examples include silicone rubbers having alkenyl groups bonded to silicon atoms (alkenyl-group-containing organopolysiloxanes; in the case of addition reaction types), silicone rubbers having at least methyl groups (in the case of peroxide curing types), and silicone rubbers having silanol groups or hydrolyzable alkoxysilyl groups at the terminals (in the case of condensation types). The weight-average molecular weight of the organopolysiloxane in the silicone rubber is, for example, 150,000 or more, preferably 280,000 to 1,000,000, and more preferably 500,000 to 900,000.

[0046] The silicone resin is not particularly limited as long as it is a silicone resin used in silicone adhesives. For example, a silicone resin having the structural unit "R3Si 1 / 2 " M unit consisting of the structural unit "SiO2" Q unit consisting of the structural unit "RSiO 3 / 2and silicone resins containing organopolysiloxanes composed of (co)polymers having at least one unit selected from the group consisting of T units consisting of "R2SiO" and D units consisting of the structural unit "R2SiO". In the structural unit, R represents a hydrocarbon group or a hydroxy group. Examples of the hydrocarbon group include aliphatic hydrocarbon groups (e.g., alkyl groups such as methyl and ethyl), alicyclic hydrocarbon groups (e.g., cycloalkyl groups such as cyclohexyl), and aromatic hydrocarbon groups (e.g., aryl groups such as phenyl and naphthyl). The ratio (ratio) of the M units to at least one unit selected from Q units, T units, and D units is preferably about 0.3 / 1 to 1.5 / 1 (preferably 0.5 / 1 to 1.3 / 1) by mole. Various functional groups, such as vinyl groups, may be introduced into the organopolysiloxane in such silicone resins, as necessary. The introduced functional group may be a functional group capable of undergoing a crosslinking reaction. The silicone resin is preferably an MQ resin composed of M units and Q units. The weight average molecular weight of the organopolysiloxane in the silicone resin is, for example, 1,000 or more, preferably 1,000 to 20,000, and more preferably 1,500 to 10,000.

[0047] The compounding ratio of silicone rubber and silicone resin is not particularly limited, but for example, it is preferable that the silicone resin is 100 to 220 parts by mass, and particularly 120 to 180 parts by mass, per 100 parts by mass of silicone rubber in total.

[0048] The silicone rubber and silicone resin may be in a mixed state in which they are simply mixed in the silicone-based pressure-sensitive adhesive composition containing them, or may react with each other to form a condensation product (particularly a partial condensation product), a crosslinked reaction product, an addition reaction product, etc.

[0049] Furthermore, silicone-based pressure-sensitive adhesive compositions containing silicone rubber and silicone resin usually contain a crosslinking agent to form a crosslinked structure. Examples of such crosslinking agents include, but are not limited to, siloxane-based crosslinking agents (silicone-based crosslinking agents) and peroxide-based crosslinking agents. Only one type of crosslinking agent may be used, or two or more types may be used.

[0050] As the siloxane-based crosslinking agent, for example, a polyorganohydrogensiloxane having two or more hydrogen atoms bonded to silicon atoms in the molecule can be preferably used. In such polyorganohydrogensiloxane, various organic groups may be bonded to the silicon atoms bonded to hydrogen atoms in addition to the hydrogen atoms. Examples of the organic group include alkyl groups such as methyl groups and ethyl groups, aryl groups such as phenyl groups, and halogenated alkyl groups. Among these, from the viewpoint of synthesis and handling, alkyl groups, particularly methyl groups, are preferred. Furthermore, the skeletal structure of the polyorganohydrogensiloxane may be linear, branched, or cyclic, but linear structures are preferred.

[0051] Examples of the peroxide-based crosslinking agent include diacyl peroxide, alkyl peroxy ester, peroxydicarbonate, monoperoxycarbonate, peroxyketal, dialkyl peroxide, hydroperoxide, ketone peroxide, etc. More specific examples include benzoyl peroxide, t-butyl peroxybenzoate, dicumyl peroxide, t-butylcumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-di-t-butylperoxyhexane, 2,4-dichloro-benzoyl peroxide, di-t-butylperoxy-diisopropylbenzene, 1,1-bis(t-butylperoxy)-3,3,5-trimethylcyclohexane, 2,5-dimethyl-2,5-di-t-butylperoxyhexyne-3, etc.

[0052] Commercially available addition-type silicone adhesives include those under the trade names "KR-3700," "KR-3701," "X-40-3237-1," "X-40-3240," and "X-40-3291-1" (all manufactured by Shin-Etsu Chemical Co., Ltd.). Commercially available peroxide-curable silicone adhesives include those under the trade names "KR-100," "KR-101-10," and "KR-130" (all manufactured by Shin-Etsu Chemical Co., Ltd.).

[0053] The silicone-based pressure-sensitive adhesive layer can be produced, for example, by applying (coating) a pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer A onto the substrate layer or release liner and drying and curing the resulting pressure-sensitive adhesive composition layer, or by applying (coating) the pressure-sensitive adhesive composition onto the substrate layer or release liner and irradiating the resulting pressure-sensitive adhesive composition layer with active energy rays to cure it. Furthermore, if necessary, the resulting pressure-sensitive adhesive composition may be further dried by heating.

[0054] Examples of the active energy rays include ionizing radiation such as α-rays, β-rays, γ-rays, neutron rays, and electron beams, as well as ultraviolet rays, with ultraviolet rays being particularly preferred. The irradiation energy, irradiation time, and irradiation method of the active energy rays are not particularly limited.

[0055] The pressure-sensitive adhesive composition may be applied (coated) using a known coating method, such as a gravure roll coater, reverse roll coater, kiss roll coater, dip roll coater, bar coater, knife coater, spray coater, comma coater, or direct coater.

[0056] The thickness of the pressure-sensitive adhesive layer A is, for example, 5 to 500 μm, and preferably 50 to 200 μm. When the thickness is 5 μm or more, the adhesiveness to the patch is superior. When the thickness is 500 μm or less (particularly, 200 μm or less), the thickness of the double-sided pressure-sensitive adhesive sheet can be made thin.

[0057] <Adhesive layer B> From the viewpoints of adhesion to the skin and safety, an acrylic pressure-sensitive adhesive is preferred as the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer B. That is, the pressure-sensitive adhesive layer is preferably an acrylic pressure-sensitive adhesive layer composed of an acrylic pressure-sensitive adhesive.

[0058] The acrylic pressure-sensitive adhesive layer contains an acrylic polymer as a base polymer. The acrylic polymer is a polymer containing an acrylic monomer (a monomer having a (meth)acryloyl group in the molecule) as a monomer component constituting the polymer. That is, the acrylic polymer contains a structural unit derived from the acrylic monomer. Only one type of acrylic polymer may be used, or two or more types may be used.

[0059] In this specification, the base polymer refers to a main component among the polymer components used in the pressure-sensitive adhesive layer, for example, a polymer component contained in an amount of more than 50% by mass. The content of the acrylic polymer in the acrylic pressure-sensitive adhesive layer is preferably 60% by mass or more, and more preferably 70% by mass or more, relative to 100% by mass of the total amount of the acrylic pressure-sensitive adhesive layer.

[0060] The acrylic polymer is preferably a polymer constituted (formed) with a (meth)acrylic acid alkyl ester as an essential monomer component. That is, the acrylic polymer preferably contains a (meth)acrylic acid alkyl ester as a constituent unit. In this specification, "(meth)acrylic" refers to "acrylic" and / or "methacrylic" (either one or both of "acrylic" and "methacrylic"), and the same applies to other terms.

[0061] The (meth)acrylic acid alkyl ester as an essential monomer component is preferably a (meth)acrylic acid alkyl ester having a linear or branched alkyl group. The (meth)acrylic acid alkyl ester may be used singly or in combination of two or more.

[0062] The (meth)acrylic acid alkyl ester having a linear or branched alkyl group is not particularly limited, and examples thereof include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, s-butyl (meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, isopentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, nonyl (meth)acrylate, and methyl (meth)acrylate. Examples of the alkyl (meth)acrylate esters include isononyl acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate (lauryl (meth)acrylate), tridecyl (meth)acrylate, tetradecyl (meth)acrylate, pentadecyl (meth)acrylate, hexadecyl (meth)acrylate, heptadecyl (meth)acrylate, octadecyl (meth)acrylate (stearyl (meth)acrylate), isostearyl (meth)acrylate, nonadecyl (meth)acrylate, and eicosyl (meth)acrylate.

[0063] Among (meth)acrylic acid alkyl esters having a linear or branched alkyl group, (meth)acrylic acid alkyl esters having a linear or branched alkyl group with 6 or more carbon atoms (preferably 6 to 18) are preferred. When the carbon number is 6 or more (particularly 6 to 18), the irritation to the skin is relatively low and the adhesive strength is less likely to decrease even with prolonged use.

[0064] The acrylic polymer may contain, as a monomer component constituting the polymer, the (meth)acrylic acid alkyl ester having the linear or branched alkyl group and another monomer (copolymerizable monomer) copolymerizable with the (meth)acrylic acid alkyl ester. That is, the acrylic polymer may contain a copolymerizable monomer as a constituent unit. The copolymerizable monomer may be used alone or in combination of two or more.

[0065] Examples of the copolymerizable monomer include a carboxy group-containing monomer, a hydroxy group-containing monomer, an epoxy group-containing monomer, a keto group-containing monomer, an alkoxy group-containing monomer, a sulfonic acid group-containing monomer, a phosphoric acid group-containing monomer, a vinyl ester-based monomer, a vinyl ether-based monomer, an isocyanate group-containing monomer, an aromatic vinyl compound, an alicyclic monomer, an aromatic ring-containing (meth)acrylate, a chlorine-containing monomer, and a nitrogen-containing monomer.

[0066] The adhesive layer B may further contain, as necessary, additives such as a tackifying resin, a filler, a crosslinking agent, a crosslinking accelerator, an antioxidant, an antioxidant, a plasticizer, a softener, a surfactant, an antistatic agent, a surface lubricant, a leveling agent, a light stabilizer, an ultraviolet absorber, a polymerization inhibitor, a foil-like material, an anticorrosive agent, and a colorant (pigment or dye), within a range that does not impair the effects of the present invention. Only one of the above additives may be used, or two or more thereof may be used.

[0067] The pressure-sensitive adhesive layer B may be in any form, for example, an emulsion type, a solvent type (solution type), an active energy ray curable type, a hot melt type (hot melt type), etc. Among these, a solvent type or an active energy ray curable type pressure-sensitive adhesive composition is preferred because it is easy to obtain a pressure-sensitive adhesive layer with excellent productivity.

[0068] Examples of the active energy rays include ionizing radiation such as α rays, β rays, γ rays, neutron rays, and electron beams, as well as ultraviolet rays, and ultraviolet rays are particularly preferred. That is, the active energy ray-curable pressure-sensitive adhesive layer is preferably an ultraviolet-curable pressure-sensitive adhesive layer.

[0069] The method for producing the acrylic pressure-sensitive adhesive layer is not particularly limited, but examples thereof include coating (applying) a pressure-sensitive adhesive (pressure-sensitive adhesive composition) containing the acrylic polymer onto the substrate layer or release liner, and drying and curing the resulting pressure-sensitive adhesive composition layer, or coating (applying) the pressure-sensitive adhesive composition onto the substrate or release liner, and irradiating the resulting pressure-sensitive adhesive composition layer with active energy rays to cure it. If necessary, the coating may be further heated and dried.

[0070] The pressure-sensitive adhesive composition can be prepared by a known or conventional method. For example, a solvent-based pressure-sensitive adhesive composition can be prepared by mixing additives, if necessary, into a solution containing the acrylic polymer. For example, an active energy ray-curable pressure-sensitive adhesive composition can be prepared by mixing additives, if necessary, into a mixture of monomer components constituting the acrylic polymer or a partial polymer thereof.

[0071] The pressure-sensitive adhesive composition may be applied (coated) using a known coating method, such as a gravure roll coater, reverse roll coater, kiss roll coater, dip roll coater, bar coater, knife coater, spray coater, comma coater, or direct coater.

[0072] The heat drying temperature for the solvent-based pressure-sensitive adhesive composition is preferably 40 to 200° C., more preferably 50 to 180° C., and even more preferably 70 to 170° C. The drying time can be appropriately selected from among various times, and is, for example, 5 seconds to 20 minutes, preferably 5 seconds to 10 minutes, and more preferably 10 seconds to 5 minutes.

[0073] When forming the pressure-sensitive adhesive layer B by irradiation with active energy rays, the acrylic polymer can be produced from the monomer component and the pressure-sensitive adhesive layer can be formed at the same time. The monomer component can be partially polymerized to form a syrup beforehand before irradiation with active energy rays. For ultraviolet irradiation, a high-pressure mercury lamp, a low-pressure mercury lamp, a metal halide lamp, or the like can be used.

[0074] The thickness of the pressure-sensitive adhesive layer B is, for example, 10 to 200 μm, and preferably 20 to 60 μm. When the thickness is 10 μm or more (particularly 20 μm or more), the conformability and adhesion to the skin are superior. When the thickness is 200 μm or less (particularly 60 μm or less), the thickness of the double-sided pressure-sensitive adhesive sheet can be made thin.

[0075] (Double-sided adhesive sheet for application to the skin) The thickness (total thickness) of the double-sided pressure-sensitive adhesive sheet for application to skin is preferably less than 1000 μm, more preferably 500 μm or less, and even more preferably 400 μm or less. A thickness of less than 1000 μm provides excellent flexibility and superior ability to follow skin movements. Furthermore, the thickness of the double-sided pressure-sensitive adhesive sheet can be reduced. The thickness is preferably 40 μm or more, more preferably 80 μm or more, even more preferably 100 μm or more, and particularly preferably 130 μm or more. A thickness of 40 μm or more (particularly 80 μm or more) provides excellent adhesion to the patch and skin. The thickness of the double-sided pressure-sensitive adhesive sheet for application to skin refers to the thickness from adhesive surface A to adhesive surface B, i.e., the thickness of the adhesive body, and does not include the release liner. In this specification, a structure comprising adhesive layer A, the substrate layer, and adhesive layer B, with adhesive surface A and adhesive surface B as both adhesive surfaces, may be referred to as an "adhesive body."

[0076] The breaking stress in at least one direction of the double-sided pressure-sensitive adhesive sheet for application to the skin (the pressure-sensitive adhesive body) is 0.8 N / mm 2 It is preferably equal to or greater than 1.0 N / mm 2 More preferably, 2.0 N / mm 2 More than 5.0N / mm2 The breaking stress is 0.8N / mm or more. 2 When the stress-reducing property is above this, the adhesive layer is less likely to break when stretched, and the flexible device as a patch has excellent followability to skin movement when attached to the skin. The breaking stress is a value measured in an environment of 23°C and 50% RH using a No. 3 dumbbell sample with a chuck distance of 50 mm and a pulling speed of 50 mm / min. In particular, it is preferable that the breaking stress in at least one of the MD and TD directions of the base layer is within the above range, and it is more preferable that the breaking stress in both directions is within the above range.

[0077] The Young's modulus in at least one direction of the double-sided pressure-sensitive adhesive sheet for application to skin (the pressure-sensitive adhesive body) is preferably 50 MPa or less, more preferably 15 MPa or less, and even more preferably 5 MPa or less. When the Young's modulus is 50 MPa or less, the flexible device as a patch will have excellent followability to skin movement when attached to the skin. The Young's modulus in at least one direction of the double-sided pressure-sensitive adhesive sheet for application to skin (the pressure-sensitive adhesive body) is, for example, 0.5 MPa or more. The Young's modulus is a value measured in an environment of 23°C and 50% RH using a No. 3 dumbbell sample with a chuck distance of 50 mm and a pulling speed of 50 mm / min. In particular, it is preferable that the Young's modulus in at least one direction of the MD and TD of the base layer is within the above range, and it is more preferable that the Young's modulus in both directions is within the above range.

[0078] The breaking elongation in at least one direction of the double-sided pressure-sensitive adhesive sheet for application to skin (the pressure-sensitive adhesive body) is preferably 50% or more, more preferably 70% or more, and even more preferably 90% or more. When the breaking elongation is 50% or more, the pressure-sensitive adhesive layer is less likely to break when stretched, and the flexible device as a patch is excellent in its ability to follow the movement of the skin when attached to the skin. The breaking elongation is a value measured using a No. 3 dumbbell sample at a chuck distance of 50 mm and a pulling rate of 50 mm / min in an environment of 23°C and 50% RH. In particular, it is preferable that the breaking elongation in at least one direction of the MD and TD of the base layer is within the above range, and it is more preferable that the breaking elongation in both directions is within the above range.

[0079] The double-sided pressure-sensitive adhesive sheet for application to skin (the pressure-sensitive adhesive body) preferably has an average total light transmittance of 40% or more at wavelengths of 400 to 700 nm, as measured in accordance with JIS K7136-1, more preferably 50% or more, and even more preferably 80% or more. When the average transmittance is 40% or more, the visible light transmittance is high, resulting in excellent transparency of the double-sided pressure-sensitive adhesive sheet and excellent visibility when applied to the skin.

[0080] The double-sided pressure-sensitive adhesive sheet for application to skin (the pressure-sensitive adhesive body) preferably has an average total light transmittance of 40% or more, more preferably 50% or more, and even more preferably 80% or more at wavelengths of 2000 to 2500 nm as measured in accordance with JIS K7136-1. When the average transmittance is 40% or more, the infrared transmittance is high and the light-sensing function is excellent.

[0081] The double-sided pressure-sensitive adhesive sheet for application to skin may have a release liner attached to the surface (adhesive surface) of the pressure-sensitive adhesive layer until use. Each adhesive surface of the double-sided pressure-sensitive adhesive sheet for application to skin may be protected by two release liners, or may be protected by a single release liner with release surfaces on both sides in a rolled form (rolled body). The release liner is used as a protective material for the pressure-sensitive adhesive layer and is peeled off when the sheet is applied to an adherend. The release liner is not necessarily provided.

[0082] The release liner can be a conventional release paper, and is not particularly limited. Examples include substrates with a release treatment layer, low-adhesion substrates made of fluoropolymers, and low-adhesion substrates made of non-polar polymers. Examples of substrates with a release treatment layer include plastic films and papers surface-treated with release agents such as silicones, long-chain alkyls, fluorines, and molybdenum sulfide. Examples of fluorine-based polymers in the low-adhesion substrates made of fluoropolymers include polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinyl fluoride, polyvinylidene fluoride, tetrafluoroethylene-hexafluoropropylene copolymers, and chlorofluoroethylene-vinylidene fluoride copolymers. Examples of non-polar polymers include olefin resins (e.g., polyethylene, polypropylene, etc.). The release liner can be formed by known or conventional methods. The thickness of the release liner is also not particularly limited.

[0083] The double-sided pressure-sensitive adhesive sheet for application to skin has excellent adhesion to patches and is used for applications in which patches are attached to the skin (skin). Examples of the patches include, but are not limited to, electronic device devices. Because adhesive surface A of the double-sided pressure-sensitive adhesive sheet for application to skin has particularly excellent adhesion to silicon atom-containing substances such as silica and silicone resins, the patch is preferably an electronic device. By applying the double-sided pressure-sensitive adhesive sheet for skin to an electronic device, an electronic device equipped with the double-sided pressure-sensitive adhesive sheet for skin can be produced.

[0084] Furthermore, when the double-sided pressure-sensitive adhesive sheet for skin has excellent adhesion to the skin and the adhesive material, and is also excellent in flexibility, it has excellent conformity to the movement of the skin and is not easily peeled off from the skin. Therefore, the adhesive material may be any of a rigid device, a semi-flexible device, and a flexible device, but a flexible device is preferred. Furthermore, it is particularly preferred that the skin is human skin. Furthermore, the double-sided pressure-sensitive adhesive sheet for skin application can have excellent transparency, and therefore has excellent light-sensing function. [Example]

[0085] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples in any way.

[0086] Example 1 (Preparation of silicone adhesive layer) An addition-type silicone adhesive (trade name "KR-3700", manufactured by Shin-Etsu Chemical Co., Ltd.) was diluted with toluene and applied to the release-treated surface of a 50 μm-thick polyester film (trade name "Diafoil MRS", manufactured by Mitsubishi Chemical Corporation), one side of which had been treated with a silicone release agent. The film was then heated at 140°C for 8 minutes and dried to form a 100 μm-thick adhesive layer (silicone adhesive layer).

[0087] (double-sided adhesive sheet) The silicone-based pressure-sensitive adhesive layer was attached to the surface of the base layer of a skin adhesive tape (product name "ST-276", manufactured by Nitto Denko Corporation) which had a pressure-sensitive adhesive layer formed on one side of the base layer and a release liner laminated on the surface of the pressure-sensitive adhesive layer. In this way, a double-sided pressure-sensitive adhesive sheet was produced in which a pressure-sensitive adhesive layer and a silicone-based pressure-sensitive adhesive layer were laminated on both sides of the base layer, and further release liners were laminated on both pressure-sensitive adhesive layers.

[0088] Example 2 A double-sided pressure-sensitive adhesive sheet was prepared in the same manner as in Example 1, except that a skin patch tape (product name "ST-279", manufactured by Nitto Denko Corporation) was used instead of a skin patch tape (product name "ST-276", manufactured by Nitto Denko Corporation).

[0089] Example 3 A double-sided pressure-sensitive adhesive sheet was prepared in the same manner as in Example 1, except that a skin patch tape (product name "ST-245", manufactured by Nitto Denko Corporation) was used instead of the skin patch tape (product name "ST-276", manufactured by Nitto Denko Corporation).

[0090] Example 4 A double-sided pressure-sensitive adhesive sheet was prepared in the same manner as in Example 1, except that a skin patch tape (product name "ST-2410", manufactured by Nitto Denko Corporation) was used instead of the skin patch tape (product name "ST-276", manufactured by Nitto Denko Corporation).

[0091] Comparative Example 1 (rubber-based adhesive layer) A hydrogenated styrene-isoprene-styrene block copolymer (trade name "2563NS", manufactured by Soken Chemical & Engineering Co., Ltd.) serving as the base polymer was dissolved in toluene to adjust the solids concentration to 25% by mass to prepare a pressure-sensitive adhesive composition. This pressure-sensitive adhesive composition was applied to the release-treated surface of a 38 μm-thick polyester film (trade name "Diafoil MRF", manufactured by Mitsubishi Chemical Corporation), one side of which had been treated with a silicone-based release agent, and then heated and dried at 120°C for 3 minutes to form a 50 μm-thick pressure-sensitive adhesive layer (rubber-based pressure-sensitive adhesive layer).

[0092] (double-sided adhesive sheet) A double-sided PSA sheet was produced in the same manner as in Example 1, except that the above rubber-based PSA layer was used instead of the silicone-based PSA layer.

[0093] Comparative Example 2 The double-sided PSA sheet prepared in Example 1 was used, except that in the evaluation described below, the adhesive layers and silicone-based adhesive layers in the skin adhesive tape were used in the opposite directions to those in Example 1.

[0094] Comparative Example 3 (acrylic adhesive layer) 40 parts by weight of butyl acrylate (BA), 40 parts by weight of cyclohexyl acrylate (CHA), 20 parts by weight of 4-hydroxybutyl acrylate (4-HBA), 0.05 parts by weight of 2,2-dimethoxy-1,2-diphenylethan-1-one (trade name "Ominrad 651" manufactured by IGM Resins BV) as a photopolymerization initiator, and 0.05 parts by weight of 1-hydroxycyclohexyl phenyl ketone (trade name "Ominrad 184" manufactured by IGM Resins BV) were mixed and irradiated with ultraviolet light under a nitrogen atmosphere to produce a partially polymerized monomer syrup. 0.1 parts by weight of dipentaerythritol hexaacrylate (DPHA) (trade name "KAYARAD DPHA" manufactured by Nippon Kayaku Co., Ltd.) was added to the resulting monomer syrup and mixed uniformly to prepare a pressure-sensitive adhesive composition.

[0095] The pressure-sensitive adhesive composition prepared above was applied to the release-treated surface of a 38 μm thick polyester film (trade name "Diafoil MRF", manufactured by Mitsubishi Chemical Corporation), one side of which had been release-treated with a silicone-based release agent, to form a coating layer. Next, a 38 μm thick polyester film (trade name "Diafoil MRE", manufactured by Mitsubishi Chemical Corporation), one side of which had been release-treated with silicone, was placed on the surface of the coating layer, with the release-treated surface of the film facing the coating layer. This blocked the coating layer from oxygen. The sheet having the coating layer thus obtained was illuminated with a chemical light lamp (manufactured by Toshiba Corporation) at an illuminance of 5 mW / cm. 2The coating layer was cured by irradiating it with ultraviolet light for 360 seconds, forming a 50 μm thick adhesive layer (acrylic adhesive layer). The illuminance values ​​were measured using an industrial UV checker (trade name "UVR-T1", manufactured by Topcon Corporation, photoreceptor model UD-T36) with a peak sensitivity wavelength of approximately 350 nm.

[0096] (double-sided adhesive sheet) A double-sided pressure-sensitive adhesive sheet was produced in the same manner as in Example 1, except that the acrylic pressure-sensitive adhesive layer was used instead of the silicone pressure-sensitive adhesive layer.

[0097] <Evaluation> The pressure-sensitive adhesive layers and double-sided pressure-sensitive adhesive sheets obtained in the examples and comparative examples were evaluated as follows, and the results are shown in the table below.

[0098] (1) Surface free energy For both adhesive surfaces of the double-sided PSA sheets produced in the Examples and Comparative Examples, the contact angles of water, diiodomethane, and 1-bromonaphthalene were measured using a contact angle meter (product name "DMo-701", manufactured by Kyowa Interface Science Co., Ltd.) The obtained contact angle values ​​were then used to calculate the surface free energy according to the Kitazaki-Hata equation.

[0099] (2) Young's modulus, elongation at break From the double-sided PSA sheets obtained in the Examples and Comparative Examples, dumbbell No. 3 shapes (JIS K6251 compliant, 5 mm wide) were punched out, and all release liners were peeled off to expose the PSA sheet. Then, under an environment of 23°C and 50% RH, all release liners were peeled off to expose the PSA sheet. An extension test was performed using a tensile tester (product name "Autograph AG-10G Tensile Tester," manufactured by Shimadzu Corporation) at a chuck distance of 50 mm and a tensile speed of 50 mm / min, stretching the test specimen until it broke. The Young's modulus was calculated from the obtained displacement and stress results. The initial chuck distance of the test specimen was set to 0%, and the difference in elongation from the initial chuck distance at the time of test specimen breakage was divided by the initial chuck distance to determine the elongation at break. The above extension test was performed in both the MD and TD directions of the substrate layer.

[0100] (3) Breaking stress Dumbbell No. 3 shapes (compliant with JIS K6251, width 5 mm) were punched out from the double-sided PSA sheets obtained in the Examples and Comparative Examples, and all release liners were peeled off to expose the PSA sheets. These were then set in a tensile testing machine "Autograph AG-I" (manufactured by Shimadzu Corporation) with a chuck distance of 50 mm in the longitudinal direction, and stretched at a tensile speed of 50 mm / min until they broke, and the load (breaking stress) was measured.

[0101] (4) Transmittance All release liners were peeled off from the double-sided PSA sheets obtained in the Examples and Comparative Examples, and the total light transmittance in the thickness direction of the double-sided PSA sheets was measured using an ultraviolet-visible-near-infrared spectrophotometer (device name "SolidSpec", manufactured by Shimadzu Corporation). The average transmittance in the wavelength range of 400 to 700 nm and the average transmittance in the wavelength range of 2000 to 2500 nm were then calculated.

[0102] (5) Adhesion of the adhesive surface of the patch Under a measurement environment of 23°C and 50% RH, a 25 μm thick PET film was attached to the skin-facing adhesive surface (see Table 1) of the double-sided PSA sheets obtained in the Examples and Comparative Examples to form a backing, and the sheet was then cut to a size of 20 mm wide and 100 mm long to prepare measurement samples. For each measurement sample, the adhesive surface (see Table 1) of the patch-facing side of the measurement sample was pressed against a silicone rubber sheet (product name "QP1-70", manufactured by Dow-Toray Industries, Inc.) using a 2 kg roller with one reciprocating motion under an environment of 23°C and 50% RH. After leaving the sheet under the same environment for 30 minutes, the 180° peel strength was measured using a triple tensile tester (product name "AG-X plus", manufactured by Shimadzu Corporation) in accordance with JIS Z0237:2000, at a tensile speed of 50 mm / min and a peel angle of 180°.

[0103] (6) Adhesion of the adhesive surface on the skin side The double-sided pressure-sensitive adhesive sheets obtained in the Examples and Comparative Examples were cut into rectangles measuring 50 mm wide x 50 mm long. A 5 μm thick PET film was attached to the adhesive surface facing the patch as a backing, and the adhesive surface facing the skin was attached to the forearms of five volunteers. After three hours at room temperature, the degree of lifting of the double-sided pressure-sensitive adhesive sheet edge was evaluated using the following three-point scale. As a result, Examples 1 to 4 were all rated 3. (Floating condition) 3: No lifting, 2: Slight lifting at the edge, 1: More than half lifted

[0104] [Table 1]

[0105] As shown in Table 1, the double-sided pressure-sensitive adhesive sheet for application to skin of the present invention was confirmed to have excellent adhesion to patches and to the skin. It is also presumed to have excellent adhesion to the skin and flexibility, and also excellent ability to follow the movement of the skin. On the other hand, when the surface free energy of the adhesive surface to which the patch is attached was high (Comparative Example), adhesion to the patch was poor. [Explanation of symbols]

[0106] 1 double-sided adhesive sheet 2 Base material layer 3,4 Adhesive layer 3a Adhesive side A 4a Adhesive side B

Claims

1. A substrate layer and a pressure-sensitive adhesive layer provided on both sides of the substrate layer, The surface free energy of one adhesive surface at a temperature of 23°C and a relative humidity of 50% is 20 mJ / m ２ is less than The other adhesive side is the side that is attached to the skin, the surface free energy of the other adhesive surface at a temperature of 23°C and a relative humidity of 50% is 20 to 50 mJ / m 2 ; A double-sided pressure-sensitive adhesive sheet for application to skin, wherein the pressure-sensitive adhesive layer providing one of the pressure-sensitive adhesive surfaces and the pressure-sensitive adhesive layer providing the other of the pressure-sensitive adhesive surfaces contain different types of base polymers.

2. The breaking stress in at least one direction is 0.8 N / mm ２ The double-sided pressure-sensitive adhesive sheet for application to skin according to claim 1 .

3. 3. The double-sided pressure-sensitive adhesive sheet for application to skin according to claim 1, wherein the Young's modulus in at least one direction is 50 MPa or less.

4. 4. The double-sided pressure-sensitive adhesive sheet for application to skin according to claim 1, wherein the one pressure-sensitive adhesive surface has a 180° peel strength from a silicone resin substrate of 2 N / 20 mm or more, measured under conditions of a temperature of 23°C and a peel rate of 50 mm / min.

5. 5. The double-sided pressure-sensitive adhesive sheet for application to skin according to any one of claims 1 to 4, wherein, in total light transmittance measured in accordance with JIS K7136-1, the average transmittance in the wavelength range of 400 to 700 nm is 40% or more, and the average transmittance in the wavelength range of 2000 to 2500 nm is 40% or more.

6. The double-sided pressure-sensitive adhesive sheet for application to skin according to any one of claims 1 to 5, which has a total thickness of less than 1000 µm.

7. The double-sided pressure-sensitive adhesive sheet for application to skin according to any one of claims 1 to 6, wherein the pressure-sensitive adhesive layer providing the other pressure-sensitive adhesive surface is an acrylic pressure-sensitive adhesive layer containing an acrylic polymer as a base polymer.

8. The double-sided pressure-sensitive adhesive sheet for application to skin according to any one of claims 1 to 7, which is used for applying an electronic device to human skin.

9. The double-sided pressure-sensitive adhesive sheet for application to skin according to claim 8 , wherein the electronic device is a flexible device.

10. An electronic device comprising the double-sided pressure-sensitive adhesive sheet for application to skin according to any one of claims 1 to 9.

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