WO2013042648A1 - Adhesive sheet for metal surface bonding - Google Patents

Adhesive sheet for metal surface bonding Download PDF

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Publication number
WO2013042648A1
WO2013042648A1 PCT/JP2012/073792 JP2012073792W WO2013042648A1 WO 2013042648 A1 WO2013042648 A1 WO 2013042648A1 JP 2012073792 W JP2012073792 W JP 2012073792W WO 2013042648 A1 WO2013042648 A1 WO 2013042648A1
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WIPO (PCT)
Prior art keywords
pressure
sensitive adhesive
adhesive sheet
acrylic acid
meth
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PCT/JP2012/073792
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French (fr)
Japanese (ja)
Inventor
大輔 山川
祐也 北出
佑輔 高橋
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Dic株式会社
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Application filed by Dic株式会社 filed Critical Dic株式会社
Priority to JP2012554546A priority Critical patent/JP5278628B1/en
Priority to CN201280019700.4A priority patent/CN103492507B/en
Priority to KR1020137020638A priority patent/KR101522231B1/en
Publication of WO2013042648A1 publication Critical patent/WO2013042648A1/en

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    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J133/00—Adhesives based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Adhesives based on derivatives of such polymers
    • C09J133/04—Homopolymers or copolymers of esters
    • C09J133/06—Homopolymers or copolymers of esters of esters containing only carbon, hydrogen and oxygen, the oxygen atom being present only as part of the carboxyl radical
    • C09J133/062—Copolymers with monomers not covered by C09J133/06
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J133/00—Adhesives based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Adhesives based on derivatives of such polymers
    • C09J133/04—Homopolymers or copolymers of esters
    • C09J133/14—Homopolymers or copolymers of esters of esters containing halogen, nitrogen, sulfur or oxygen atoms in addition to the carboxy oxygen
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J7/00—Adhesives in the form of films or foils
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J7/00—Adhesives in the form of films or foils
    • C09J7/30—Adhesives in the form of films or foils characterised by the adhesive composition
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J7/00—Adhesives in the form of films or foils
    • C09J7/30—Adhesives in the form of films or foils characterised by the adhesive composition
    • C09J7/38—Pressure-sensitive adhesives [PSA]
    • C09J7/381—Pressure-sensitive adhesives [PSA] based on macromolecular compounds obtained by reactions involving only carbon-to-carbon unsaturated bonds
    • C09J7/385—Acrylic polymers
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J2203/00—Applications of adhesives in processes or use of adhesives in the form of films or foils
    • C09J2203/318—Applications of adhesives in processes or use of adhesives in the form of films or foils for the production of liquid crystal displays

Definitions

  • This invention relates to the adhesive sheet affixed on a metal surface.
  • touch sensors have begun to be installed in electronic devices.
  • the touch sensors for electronic devices are mainly equipped with a resistive touch panel that detects the pressure at the time of input and a capacitive touch panel that detects the input location by static electricity from the human body at the time of input.
  • the capacitive method is becoming mainstream.
  • a transparent metal film in which a conductive layer is provided on a transparent film substrate or glass is used for the touch panel, and in the capacitive touch panel, the metal layer surface of the transparent metal film is adhered to a double-sided adhesive sheet. It is fixed so as to be in contact with the surface of the agent layer.
  • the metal layer of the transparent metal film is formed by evaporating a highly transparent and conductive metal such as indium tin oxide, and a double-sided pressure-sensitive adhesive sheet is attached so that the pressure-sensitive adhesive layer is in contact with the metal layer surface of the metal film.
  • a highly transparent and conductive metal such as indium tin oxide
  • a double-sided pressure-sensitive adhesive sheet is attached so that the pressure-sensitive adhesive layer is in contact with the metal layer surface of the metal film.
  • double-sided pressure-sensitive adhesive sheet having metal corrosion prevention properties double-sided pressure-sensitive adhesive sheets that do not contain an acid component (see, for example, Patent Documents 1 to 3) because the acid component contained in the pressure-sensitive adhesive layer causes corrosion of the metal. Proposed.
  • the double-sided pressure-sensitive adhesive sheet has metal corrosion prevention properties due to a pressure-sensitive adhesive layer that does not contain an acid component that causes corrosion of the metal.
  • the pressure-sensitive adhesive sheet containing no acid component has a problem that the hydrophilicity of the pressure-sensitive adhesive layer is lowered, and the pressure-sensitive adhesive layer becomes cloudy under high temperature and high humidity.
  • the problem to be solved by the present invention is to provide a pressure-sensitive adhesive sheet that does not corrode the metal surface even when directly bonded to the metal surface, and is less likely to deteriorate in visibility due to white turbidity in a high-temperature environment. is there.
  • a specific amount of the (meth) acrylic acid alkoxyalkyl ester monomer and the (meth) acrylic acid alkyl ester monomer having an alkyl group having 1 to 4 carbon atoms are used together in the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet.
  • the present invention is a pressure-sensitive adhesive sheet to be bonded to a metal surface, the pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer made of an acrylic pressure-sensitive adhesive using a (meth) acrylic acid ester copolymer,
  • the acrylic acid ester copolymer comprises (meth) acrylic acid alkoxyalkyl ester monomer (A) and (meth) acrylic acid alkyl ester (B) having an acrylic group having 1 to 4 carbon atoms as monomer components.
  • the content of the (meth) acrylic acid alkoxyalkyl ester monomer (A) in the monomer component constituting the (meth) acrylic acid ester copolymer is 50% by mass or more, and the number of carbon atoms is
  • the content of the (meth) acrylic acid alkyl ester (B) having 1 to 4 acrylic groups is 5 to 45% by mass, and constitutes a (meth) acrylic acid ester copolymer
  • the content of the carboxyl group-containing monomer in the dimer component is to provide an adhesive sheet for sticking a metal surface is not more than 1%.
  • the pressure-sensitive adhesive sheet for sticking a metal surface of the present invention is a (meth) acrylic acid alkyl ester monomer having a specific amount of a (meth) acrylic acid alkoxyalkyl ester monomer and an alkyl group having 1 to 4 carbon atoms in the pressure-sensitive adhesive layer.
  • (Meth) acrylic acid ester copolymer is included, so even if the content of the carboxyl group-containing monomer is small, the pressure-sensitive adhesive layer is highly hydrophilic and can be used under high temperature and high humidity conditions. The layer does not become cloudy and further prevents corrosion of the metal.
  • the pressure-sensitive adhesive sheet for sticking a metal surface of the present invention is a pressure-sensitive adhesive sheet to be bonded to a metal surface, and the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet has (meth) acrylic acid alkoxyalkyl ester monomer (A) and 1 carbon number.
  • a pressure-sensitive adhesive layer comprising a (meth) acrylic acid ester copolymer containing a (meth) acrylic acid alkyl ester monomer (B) having an alkyl group of 4 to 4 as a main monomer, the (meth) acrylic
  • the content of the (meth) acrylic acid alkoxyalkyl ester monomer (A) in the monomer component constituting the acid ester copolymer is 50% by mass or more and has an alkyl group having 1 to 4 carbon atoms (meta )
  • a pressure-sensitive adhesive sheet having an acrylic acid alkyl ester monomer (B) content of 5 to 45% by mass and a carboxyl group-containing monomer content of 1% by mass or less.
  • (meth) acrylic acid alkoxyalkyl ester monomer (A) constituting the (meth) acrylic acid ester copolymer of the present invention include 2-methoxyethyl acrylate and 2-ethoxyethyl acrylate. , 2-methoxytriethylene glycol acrylate, 3-methoxypropyl acrylate, 3-ethoxypropyl acrylate, 4-methoxybutyl acrylate, 4-ethoxybutyl acrylate, and the like. Of these, 2-methoxyethyl acrylate and 2-ethoxyethyl acrylate are particularly preferable.
  • cohesive force necessary for fixing the metal film to the pressure-sensitive adhesive layer can be imparted.
  • acrylic acid and methacrylic acid are collectively referred to as (meth) acrylic acid, and these derivatives are also represented in the same manner.
  • the content of the (meth) acrylic acid alkoxyalkyl ester monomer (A) with respect to 100% by mass of all monomer components constituting the (meth) acrylic acid ester copolymer is preferably 50 to 90% by mass, preferably 60 to 90% by mass is more preferable, 70 to 90% by mass is further preferable, and 75 to 85% by mass is particularly preferable.
  • the (meth) acrylic acid alkyl ester monomer (B) having an alkyl group having 1 to 4 carbon atoms constituting the (meth) acrylic acid ester copolymer of the present invention includes the above (meth) acrylic acid alkoxyalkyl ester.
  • n-butyl acrylate is particularly preferable.
  • n-butyl acrylate it is possible to achieve both high adhesion to a metal surface and white turbidity resistance under high temperature and high humidity conditions.
  • the content of the (meth) acrylic acid ester monomer (B) having 1 to 4 carbon atoms with respect to 100% by mass of all monomer components constituting the (meth) acrylic acid ester copolymer is 5 to 45% by mass. Preferably, it is 5 to 35% by mass, more preferably 5 to 25% by mass, and particularly preferably 10 to 25% by mass.
  • Acrylic acid methacrylic acid, itaconic acid, maleic acid, crotonic acid, acrylic acid dimer, ethylene
  • examples thereof include oxide-modified succinic acid acrylate. Of these, acrylic acid is preferred because of its high versatility.
  • the amount of the carboxyl group-containing monomer used is 1% by mass or less in the monomer component constituting the acrylic copolymer, more preferably 0.5% by mass or less, and more preferably 0.1% by mass or less. In particular, it is particularly preferable not to contain it. By setting the content of the carboxyl group-containing monomer within the range, corrosion of the metal can be prevented.
  • a vinyl monomer having a functional group that reacts with the crosslinking agent in order to increase the cohesive strength of the pressure-sensitive adhesive layer by suitably crosslinking with the crosslinking agent.
  • the vinyl monomer having a functional group that reacts with the crosslinking agent is not particularly limited, but a hydroxyl group-containing vinyl monomer such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 4-hydroxybutyl acrylate, etc. Is mentioned.
  • the amount of the vinyl monomer having a functional group used is preferably 0.1% by mass to 10% by mass, and preferably 0.5% by mass to 5% by mass in the monomer component constituting the acrylic copolymer. It is particularly preferred.
  • the weight average molecular weight Mw of the (meth) acrylic acid ester copolymer is preferably 300,000 to 1,600,000, more preferably 400,000 to 1,300,000, and further preferably 500,000 to 1,000,000.
  • the weight average molecular weight Mw of the (meth) acrylic acid ester copolymer is within the above range, the adhesiveness to the metal surface and the followability to the unevenness of the metal to be attached and the display panel can be suitably imparted.
  • the molecular weight distribution (weight average molecular weight Mw / number average molecular weight Mn) of the (meth) acrylate copolymer is preferably 10 to 50, more preferably 10 to 30, and still more preferably 10 to 20.
  • the molecular weight distribution (weight average molecular weight Mw / number average molecular weight Mn) of the (meth) acrylic acid ester copolymer is within this range, it is possible to provide follow-up to the unevenness of the metal to be affixed and the display panel, and there are bubbles in the display screen portion. Is less likely to remain, and further peeling from the metal surface can be suppressed.
  • the weight average molecular weight Mw of the carboxyl group-containing (meth) acrylic acid ester copolymer (A) can be measured by gel permeation chromatography (GPC). More specifically, as a GPC measurement device, “SC8020” manufactured by Tosoh Corporation can be used to measure and obtain the following GPC measurement conditions based on polystyrene conversion values.
  • GPC gel permeation chromatography
  • the polymerization method of the (meth) acrylic acid ester copolymer used in the present invention is not particularly limited, and various known polymerization methods can be used as appropriate.
  • Thermal polymerization methods such as solution polymerization method, emulsion polymerization method, bulk polymerization method, A polymerization method performed by irradiating active energy rays such as light and radiation can be employed.
  • a solution polymerization method can be preferably adopted, and any of a batch charging method in which the entire amount of monomer components are supplied to the reaction vessel at once, a dropping method in which continuous or divided supply is used, etc. There may be.
  • organic solvents used for the solution polymerization various organic solvents used for the solution polymerization can be used, and among them, the use of a non-toluene organic solvent is preferable.
  • preferable organic solvents include ethyl acetate, hexane, cyclohexane, methylcyclohexane, isopropyl alcohol and the like.
  • other organic solvents that can be preferably used include 1-butanol, secondary butanol, tertiary butanol, tertiary butyl methyl ether, methyl ethyl ketone, acetylacetone, 1,2-dichloroethane and the like.
  • the pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet for metal surface sticking of the present invention is a pressure-sensitive adhesive composition containing the above (meth) acrylic acid ester copolymer, As a component other than the copolymer, it is preferable to contain a crosslinking agent in order to increase the cohesive strength of the pressure-sensitive adhesive layer.
  • crosslinking agent used examples include isocyanate crosslinking agents, epoxy crosslinking agents, chelating crosslinking agents, azirine crosslinking agents, and polyfunctional acrylates.
  • isocyanate-based crosslinking agent rich in reactivity with the components of the (meth) acrylic copolymer is preferable.
  • the amount of the crosslinking agent added to the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet is preferably 0.05 to 2 parts by weight, more preferably 0.07 to 1.5 parts by weight, and still more preferably 0.1 to 1 part by weight. .
  • the content of the crosslinking agent in this range it is easy to adjust the gel fraction of the pressure-sensitive adhesive layer to a suitable range.
  • the pressure-sensitive adhesive composition of the present invention is preferably a pressure-sensitive adhesive composition in which the (meth) acrylic acid ester copolymer and the crosslinking agent are dissolved or dispersed in a solvent, and the solvent is a solvent used for the solution polymerization.
  • the same solvent as can be preferably used.
  • the pressure-sensitive adhesive composition of the present invention may contain other general additives such as ultraviolet absorbers, light stabilizers, anti-aging agents, release modifiers, tackifiers, plasticizers as necessary. Agents, softeners, fillers, colorants (such as pigments and dyes), surfactants, and the like may be included.
  • the pressure-sensitive adhesive sheet for metal surface sticking of the present invention can suppress the cloudiness of the pressure-sensitive adhesive layer and corrosion of the metal under high-temperature and high-humidity conditions by having the pressure-sensitive adhesive layer made of the above-mentioned pressure-sensitive adhesive composition as the pressure-sensitive adhesive layer. .
  • the pressure-sensitive adhesive sheet for sticking a metal surface of the present invention may be a pressure-sensitive adhesive sheet having only a pressure-sensitive adhesive layer without having a film base material. Moreover, even if the adhesive layer consists of a single layer, multiple layers may be laminated
  • Fixing the adhesive sheet of the present invention between components for example, fixing a surface protection panel on the surface of an image display device and a member having a metal surface such as ITO film or glass, or fixing members having metal surfaces.
  • a pressure-sensitive adhesive sheet for fixing between parts the form of a double-sided pressure-sensitive adhesive sheet can be preferably used, and in particular, from the viewpoint of ensuring transparency and shape followability, it does not have a substrate, and is a pressure-sensitive adhesive It is preferable that it is an adhesive sheet which consists only of layers.
  • the double-sided pressure-sensitive adhesive sheet in this form is particularly suitable for a member having an uneven surface shape such as a surface protection panel in which one member has a printed step.
  • the form of the pressure-sensitive adhesive sheet having a film base can be preferably used, and the form of a single-sided pressure-sensitive adhesive sheet in which a pressure-sensitive adhesive layer is provided on one side of a film base provided with a hard coat layer on one side can be preferably used.
  • a transparent film substrate can be used as the substrate.
  • the transparent substrate for example, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyethylene film, polypropylene film, cellophane, diacetyl cellulose film, triacetyl cellulose film, acetyl cellulose butyrate film, polyvinyl chloride film, polyvinyl chloride Vinylidene film, polyvinyl alcohol film, ethylene-vinyl acetate copolymer film, polystyrene film, polycarbonate film, polymethylpentene film, polysulfone film, polyetheretherketone film, polyethersulfone film, polyetherimide film, polyimide film, fluorine Resin film, nylon film, acrylic resin film, etc. Rukoto can. Of these, polyethylene terephthalate having excellent transparency and smoothness is preferable.
  • the film substrate used for the adhesive sheet for sticking a metal surface of the present invention has a surface unevenness treatment by a sandblasting method or a solvent treatment method, or a corona discharge treatment, for the purpose of improving the adhesion with the adhesive layer.
  • Surface treatment such as surface oxidation treatment such as chromic acid treatment, flame treatment, hot air treatment, ozone / ultraviolet irradiation treatment and the like can be performed.
  • the film substrate of the pressure-sensitive adhesive sheet for sticking a metal surface of the present invention is preferably a hard coat film having a hard coat layer on at least one surface in order to prevent appearance defects such as scratches and dents mixed during the production process.
  • a hard coat layer containing an acrylic resin is preferable. By containing the acrylic resin, it is possible to ensure adhesion to the hard coat surface.
  • surface of the said hard coat film can be used conveniently as an adhesive sheet for scattering prevention.
  • the pressure-sensitive adhesive sheet for sticking a metal surface of the present invention is a pressure-sensitive adhesive sheet for sticking a metal surface provided with a pressure-sensitive adhesive layer on one side of a hard coat film, and when the pressure-sensitive adhesive sheet is used as a pressure-sensitive adhesive sheet for preventing scattering, It is preferable that the surface pencil hardness of the hard coat layer surface of the coat film is B or more, preferably F or more. Further, the thickness of the hard coat layer is preferably 1 to 5 ⁇ m.
  • the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet for metal surface sticking according to the present invention preferably has a gel fraction represented by the following formula of 30 to 80% by mass when immersed in toluene for 24 hours, preferably 30 to 70% by mass. % Is more preferable, and 35 to 55% by mass is most preferable.
  • % is more preferable, and 35 to 55% by mass is most preferable.
  • Gel fraction (% by mass) [(mass after immersion of the adhesive layer in toluene) / (mass before adhesion of the adhesive layer in toluene)] ⁇ 100
  • the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet for attaching a metal surface of the present invention has a storage elastic modulus of 4.0 ⁇ 10 4 to 9.0 ⁇ as a storage elastic modulus at 70 ° C. of a dynamic viscoelastic spectrum measured at a frequency of 1 Hz. It is preferably included in the range of 10 5 , more preferably 4.0 ⁇ 10 4 to 8.0 ⁇ 10 4, and most preferably 4.0 ⁇ 10 4 to 7.0 ⁇ 10 4 . By including the storage elastic modulus within this range, it is possible to achieve both fluidity following the stepped portion and suppression of peeling due to warpage.
  • the dynamic viscoelasticity of the pressure-sensitive adhesive layer in the present invention is obtained by sandwiching a test piece between parallel disks, which are measuring parts of the tester, using a viscoelasticity tester (manufactured by Rheometrics, trade name: Ares 2KSTD). , Obtained by measuring the storage elastic modulus (G ′) and loss elastic modulus (G ′′) at a frequency of 1 Hz. However, in the latter case, the thickness of the pressure-sensitive adhesive is adjusted to be in the above-mentioned range. .
  • the transparency of the pressure-sensitive adhesive sheet for sticking a metal surface of the present invention is preferably such that the total light transmittance is 80% or more and the haze is 1.0% or less, the total light transmittance is 90% or more, and the haze is 0.5. % Or less is more preferable.
  • the transparency of the transparent conductive film is within the above range, the transparency of the display equipped with the touch panel device using the adhesive film is easily maintained.
  • the metal to which the pressure-sensitive adhesive sheet for metal surface application of the present invention is attached is not particularly limited, and specific examples include indium tin oxide, indium oxide, tin oxide, zinc oxide, cadmium oxide, gallium oxide, titanium oxide and the like. It is done.
  • the pressure-sensitive adhesive sheet for sticking a metal surface of the present invention is subjected to one-time reciprocation using a 2 kg roller in a temperature of 23 ° C. and a relative humidity of 50% RH, and left for 1 hour.
  • the 180 ° peel adhesion at 300 mm / min is preferably 5 to 20 N / 25 mm for each metal. Within the above range, it is easy to suppress peeling from the end face in fixing the transparent conductive film, and the pressure-sensitive adhesive sheet can be peeled in a poorly bonded product in the manufacturing process.
  • the thickness of the pressure-sensitive adhesive sheet for sticking a metal surface of the present invention may be appropriately selected depending on the mode of use, but is preferably 5 to 500 ⁇ m. In particular, when bonding to a smooth surface, it is easy to make the touch panel device thinner by adjusting to 10 to 250 ⁇ m. Further, when affixing to a surface having a step or unevenness, the thickness of the pressure-sensitive adhesive layer is preferably 20 ⁇ m or more, and particularly preferably 25 to 150 ⁇ m.
  • the pressure-sensitive adhesive sheet for attaching a metal surface of the present invention can be prepared by a generally used method. For example, it can be produced by forming an adhesive layer on a film substrate or a release sheet. Specifically, the adhesive composition is directly applied to the base film and dried or cured / polymerized, or once applied on the release sheet and dried / cured / polymerized to form an adhesive layer. Similarly, it can be produced by a method of bonding to an adhesive layer or a base film prepared on a release sheet.
  • the adhesive sheet for sticking a metal surface of the present invention does not corrode the metal surface and has good whitening resistance, so that ITO glass or ITO film provided with indium tin oxide (ITO) on the surface of the glass or film, Or it can use conveniently, when fixing the member which has metal surface surfaces, such as a metal wiring film by which the wiring of silver or copper was provided in the surface of glass or a film. Especially, it can use suitably for fixation of the member which has a metal surface surface for which high transparency is calculated
  • ITO indium tin oxide
  • the member to be fixed can be suitably applied even if it is a member having a surface uneven shape, for example, a member provided with a printing step. .
  • the pressure-sensitive adhesive sheet for metal surface application of the present invention for example, ITO in a touch sensor used in an image display unit of an electronic device, which requires high transparency and stable conductivity, is required.
  • ITO in a touch sensor used in an image display unit of an electronic device, which requires high transparency and stable conductivity
  • the configuration as shown in FIG. 1 can be preferably exemplified. In the application example in FIG.
  • the surface protection panel 2 having the printing step 3 and the ITO film 4 having the ITO surface 4 b on the transparent resin film 4 a are applied to the baseless pressure-sensitive adhesive sheet 1 for attaching a metal surface of the present invention.
  • the adhesive sheet of the present invention can be suitably used for such applications.
  • an image display module 6 such as an LCD module is provided in the housing 5, and the housing and the transparent resin film 4 a side of the ITO film 4 ′ are fixed by an adhesive member 7 such as an adhesive tape or an adhesive tape.
  • the ITO surface 4b 'of the ITO film 4' and the transparent resin film 4a surface of the ITO film 4 can be suitably used for the purpose of fixing by the adhesive sheet '1 for sticking a metal surface of the present invention without a substrate. .
  • FIGS. 2 and 3 can be preferably exemplified.
  • the application example in FIG. 2 has an ITO surface 14 on which one surface is treated with ITO, and an adhesive sheet for preventing scattering of the surface protection panel on the ITO surface 14 of the surface protection panel 12 provided with a printing step 13 on the surface.
  • the pressure-sensitive adhesive sheet 11 for sticking a metal surface of the present invention having the pressure-sensitive adhesive layer 15 on one surface of the hard coat film 16 is applied.
  • the hard coat film 16 of the adhesive sheet 11 for attaching a metal surface and the casing 17 having an image display module 18 such as an LCD module are fixed by an adhesive member 19.
  • the surface protection panel 22 having the printing step 23 and the ITO glass 24 having the ITO surfaces 24b and 24c on the transparent glass 24a are bonded to the substrate-less adhesive for metal surface of the present invention. It is a use fixed by the sheet
  • the pressure-sensitive adhesive sheet 21 'for attaching a metal surface of the present invention having the pressure-sensitive adhesive layer 26 on one surface of the hard coat film 25 can be applied.
  • the hard coat film 25 of the metal surface sticking adhesive sheet 21 ′ and the housing 27 having the image display module 28 such as an LCD module are fixed by the adhesive member 29 as in FIG. 2.
  • ⁇ Acrylic copolymer (1)> Preparation of acrylic copolymer In a reaction vessel equipped with a stirrer, cold flow cooler, thermometer, dropping funnel and nitrogen gas inlet, 2-methoxyethyl acrylate 75% by mass, n-butyl acrylate 24% by mass, acrylic acid 1% by mass of hydroxyethyl and 0.2 part of 2,2′-azobisisobutylnitrile as a polymerization initiator are dissolved in 100% by mass of ethyl acetate, and after nitrogen substitution, polymerized at 80 ° C. for 8 hours to give a weight average molecular weight of 70 Ten thousand acrylic acid ester copolymers (1) were obtained.
  • ⁇ Acrylic copolymer (2)> Acrylate ester copolymer having a weight average molecular weight of 700,000 was obtained in the same manner as in the acrylate ester copolymer (1) except that 2-methoxyethyl acrylate was 85% by mass and n-butyl acrylate was 14% by mass. Combined (2) was obtained.
  • ⁇ Acrylic copolymer (4)> Acrylate ester copolymer having a weight average molecular weight of 1,000,000 is the same as that of the acrylate ester copolymer (1) except that 50% by mass of 2-methoxyethyl acrylate and 49% by mass of n-butyl acrylate are used. Combined (4) was obtained.
  • ⁇ Acrylic copolymer (5)> Preparation of acrylic copolymer In a reaction vessel equipped with a stirrer, cold flow cooler, thermometer, dropping funnel and nitrogen gas inlet, n-butyl acrylate 80% by mass, methyl methacrylate 19% by mass, hydroxyethyl acrylate 1% by mass % And 0.22 part of 2,2′-azobisisobutylnitrile as a polymerization initiator are dissolved in 100% by mass of ethyl acetate, purged with nitrogen, polymerized at 80 ° C. for 8 hours, and acrylic acid having a weight average molecular weight of 800,000 An ester copolymer (5) was obtained.
  • ⁇ Acrylic copolymer (6)> Preparation of acrylic copolymer In a reaction vessel equipped with a stirrer, cold flow condenser, thermometer, dropping funnel and nitrogen gas inlet, n-butyl acrylate 80% by mass, acrylic acid 19% by mass, hydroxyethyl acrylate 1% by mass And 0.22 part of 2,2′-azobisisobutylnitrile as a polymerization initiator are dissolved in 100% by mass of ethyl acetate, and after substitution with nitrogen, polymerization is carried out at 80 ° C. for 8 hours to obtain an acrylic ester having a weight average molecular weight of 700,000. A copolymer (6) was obtained.
  • ⁇ Acrylic copolymer (7)> Preparation of acrylic copolymer In a reaction vessel equipped with a stirrer, cold flow cooler, thermometer, dropping funnel and nitrogen gas inlet, 2-methoxyethyl acrylate 75% by mass, n-butyl acrylate 16% by mass, methacrylic acid 8% by mass of methyl, 1% by mass of hydroxyethyl acrylate and 0.2 part of 2,2′-azobisisobutylnitrile as a polymerization initiator were dissolved in 100% by mass of ethyl acetate, and after nitrogen substitution, 8 hours at 80 ° C. Polymerization gave an acrylic ester copolymer (7) having a weight average molecular weight of 700,000.
  • ⁇ Acrylic copolymer (8)> Preparation of acrylic copolymer In a reaction vessel equipped with a stirrer, cold flow cooler, thermometer, dropping funnel and nitrogen gas inlet, 75% by mass of 2-methoxyethyl acrylate, 24% by mass of n-butyl acrylate, 4% of acrylic acid -1% by weight of hydroxybutyl and 0.2 part of 2,2'-azobisisobutylnitrile as a polymerization initiator are dissolved in 100% by weight of ethyl acetate, and after nitrogen substitution, polymerized at 80 ° C for 8 hours to obtain a weight average molecular weight 700,000 acrylic ester copolymer (8) was obtained.
  • ⁇ Acrylic copolymer (10)> Preparation of acrylic copolymer In a reaction vessel equipped with a stirrer, cold flow cooler, thermometer, dropping funnel and nitrogen gas inlet, 2-methoxyethyl acrylate 40% by mass, n-butyl acrylate 24% by mass, acrylic acid Dissolve 35% by mass of 2-ethylhexyl, 1% by mass of hydroxyethyl acrylate, and 0.2 part of 2,2′-azobisisobutylnitrile as a polymerization initiator in 100% by mass of ethyl acetate. Polymerization with time was carried out to obtain an acrylate copolymer (10) having a weight average molecular weight of 700,000.
  • ⁇ Acrylic copolymer (11)> Preparation of acrylic copolymer In a reaction vessel equipped with a stirrer, cold flow cooler, thermometer, dropping funnel and nitrogen gas inlet, 2-methoxyethyl acrylate 70% by mass, n-butyl acrylate 24% by mass, acrylic acid 1% by mass of hydroxyethyl, 5% by mass of acrylic acid and 0.2 part of 2,2′-azobisisobutylnitrile as a polymerization initiator are dissolved in 100% by mass of ethyl acetate, and after substitution with nitrogen, polymerization is carried out at 80 ° C. for 8 hours. As a result, an acrylic ester copolymer (11) having a weight average molecular weight of 700,000 was obtained.
  • ⁇ Adhesive composition (a)> The acrylic ester copolymer (1) was diluted with ethyl acetate to obtain a pressure-sensitive adhesive composition (a) having a resin solid content of 30% by mass.
  • ⁇ Adhesive composition (b)> The acrylic ester copolymer (2) was diluted with ethyl acetate to obtain a pressure-sensitive adhesive composition (b) having a resin solid content of 30% by mass.
  • ⁇ Adhesive composition (c)> The acrylic ester copolymer (3) was diluted with ethyl acetate to obtain a pressure-sensitive adhesive composition (c) having a resin solid content of 30% by mass.
  • ⁇ Adhesive composition (d)> The acrylic ester copolymer (4) was diluted with ethyl acetate to obtain a pressure-sensitive adhesive (d) having a resin solid content of 30% by mass.
  • ⁇ Adhesive composition (e)> The acrylic ester copolymer (5) was diluted with ethyl acetate to obtain a pressure-sensitive adhesive composition (e) having a resin solid content of 30% by mass.
  • ⁇ Adhesive composition (f)> The acrylic ester copolymer (6) was diluted with ethyl acetate to obtain a pressure-sensitive adhesive composition (f) having a resin solid content of 30% by mass.
  • ⁇ Adhesive composition (g)> The acrylic ester copolymer (7) was diluted with ethyl acetate to obtain a pressure-sensitive adhesive composition (g) having a resin solid content of 30% by mass.
  • ⁇ Adhesive composition (h)> The acrylic ester copolymer (8) was diluted with ethyl acetate to obtain a pressure-sensitive adhesive composition (h) having a resin solid content of 30% by mass.
  • ⁇ Adhesive composition (i)> The acrylic ester copolymer (9) was diluted with ethyl acetate to obtain a pressure-sensitive adhesive composition (i) having a resin solid content of 30% by mass.
  • ⁇ Adhesive composition (j)> The acrylic ester copolymer (10) was diluted with ethyl acetate to obtain a pressure-sensitive adhesive composition (j) having a resin solid content of 30% by mass.
  • ⁇ Adhesive composition (k)> The acrylic ester copolymer (11) was diluted with ethyl acetate to obtain a pressure-sensitive adhesive composition (k) having a resin solid content of 30% by mass.
  • Example 1 0.1 parts by mass of an isocyanate crosslinking agent (Nihon Polyurethane Coronate HX, solid content 75%) was added to 100 parts by mass of the pressure-sensitive adhesive composition (a), and the mixture was stirred for 15 minutes. It was coated on a 50 ⁇ m thick polyester film (hereinafter referred to as # 75 release film) so that the thickness after drying was 50 ⁇ m, and dried at 75 ° C. for 5 minutes. The obtained pressure-sensitive adhesive sheet and a 38 ⁇ m-thick polyester film (hereinafter referred to as # 38 release film) having one surface peel-treated with a silicone compound were bonded together. Thereafter, it was aged at 23 ° C. for 7 days to obtain a substrate-less pressure-sensitive adhesive sheet having a thickness of 50 ⁇ m and a gel fraction of 50%.
  • an isocyanate crosslinking agent Nihon Polyurethane Coronate HX, solid content 75
  • Example 2 A pressure-sensitive adhesive sheet having a gel fraction of 40% was obtained in the same manner as in Example 1 except that the isocyanate-based crosslinking agent was changed to 0.08 parts by mass.
  • Example 3 A pressure-sensitive adhesive sheet having a gel fraction of 50% was obtained in the same manner as in Example 1 except that 100 parts by weight of the pressure-sensitive adhesive composition (a) was changed to 100 parts by weight of the pressure-sensitive adhesive composition (b).
  • Example 4 The gel fraction is 40% in the same manner as in Example 1 except that 100 parts by mass of the pressure-sensitive adhesive composition (a) is 100 parts by mass of the pressure-sensitive adhesive composition (b) and 0.08 parts by mass of the isocyanate-based crosslinking agent. An adhesive sheet was obtained.
  • Example 5 A pressure-sensitive adhesive sheet having a gel fraction of 50% was obtained in the same manner as in Example 1 except that 100 parts by weight of the pressure-sensitive adhesive composition (a) was changed to 100 parts by weight of the pressure-sensitive adhesive composition (g).
  • Example 6 A pressure-sensitive adhesive sheet having a gel fraction of 50% was obtained in the same manner as in Example 1 except that 100 parts by weight of the pressure-sensitive adhesive composition (a) was changed to 100 parts by weight of the pressure-sensitive adhesive composition (h).
  • Example 7 A pressure-sensitive adhesive sheet having a gel fraction of 55% was obtained in the same manner as in Example 1 except that 100 parts by weight of the pressure-sensitive adhesive composition (a) was changed to 100 parts by weight of the pressure-sensitive adhesive composition (i).
  • Example 1 A pressure-sensitive adhesive sheet having a gel fraction of 60% was obtained in the same manner as in Example 1 except that 100 parts by weight of the pressure-sensitive adhesive composition (a) was changed to 100 parts by weight of the pressure-sensitive adhesive composition (c).
  • Example 2 A pressure-sensitive adhesive sheet having a gel fraction of 60% was obtained in the same manner as in Example 1 except that 100 parts by weight of the pressure-sensitive adhesive composition (a) was changed to 100 parts by weight of the pressure-sensitive adhesive composition (d).
  • Example 3 A pressure-sensitive adhesive sheet having a gel fraction of 60% was obtained in the same manner as in Example 1 except that 100 parts by weight of the pressure-sensitive adhesive composition (a) was changed to 100 parts by weight of the pressure-sensitive adhesive composition (e).
  • Example 5 The gel fraction was 80% in the same manner as in Example 1 except that 100 parts by mass of the pressure-sensitive adhesive composition (a) was changed to 100 parts by mass of the pressure-sensitive adhesive composition (j) and 0.3 parts by mass of the isocyanate crosslinking agent. An adhesive sheet was obtained.
  • the resistance value (R2) was measured.
  • Print level followability evaluation 1 The release film on one side of the prepared pressure-sensitive adhesive sheet was peeled off, and bonded to a polyethylene terephthalate film having a thickness of 100 ⁇ m, a length of 50 mm, and a width of 40 mm in which a printing layer having a thickness of 15 ⁇ m and a width of 5 mm was decorated in a frame shape.
  • the release film on one side where the obtained test piece remained was peeled off and bonded to a glass plate having a thickness of 1 mm, a length of 50 mm, and a width of 40 mm, and a heat and pressure treatment was performed under the conditions of 5 atm, 70 ° C., and 20 minutes.
  • the release film on one side of the pressure-sensitive adhesive sheet prepared in Example 1 is peeled off, and the pressure-sensitive adhesive sheet is bonded to the surface having no hard coat of the hard coat film provided with a hard coat layer on one surface of the polyethylene terephthalate film.
  • surface of the base material which has a layer was obtained. The following evaluation was performed about the obtained scattering prevention adhesive sheet. The results obtained are shown in Table 3.
  • Print step follow-up evaluation 2 The release film on one side of the obtained pressure-sensitive adhesive sheet is peeled off, and the printed layer is bonded to a glass plate decorated in a frame shape with a thickness of 1 mm, a length of 50 mm, and a width of 40 mm. A pressure treatment was performed. Immediately after the heating and pressurizing treatment, the entire printed decorative part was observed with a microscope (magnification 300 times), and it was confirmed whether bubbles were mixed.
  • the evaluation criteria for bubble contamination were as follows. ⁇ : No bubbles with a diameter of 5 ⁇ m or more ⁇ : No bubbles with a diameter of 30 ⁇ m or more ⁇ : Bubbles with a diameter of 30 ⁇ m or more or peeling
  • the adhesive sheets of Examples 1 to 7 did not increase in haze and did not become cloudy under high temperature and high humidity conditions even without a carboxyl group-containing monomer.
  • the pressure-sensitive adhesive sheets of Examples 1 to 4 are excellent in following a printing step, and have a good printing step following property even when a hard coat film provided with a hard coat layer is used as a base material. It was.
  • Comparative Example 1 using 2-ethylhexyl acrylate having 8 carbon atoms, the content of n-butyl acrylate having 4 carbon atoms is 49% by mass
  • Comparative Example 2 of Comparative Example 3 Comparative Example 3 not containing a highly hydrophilic alkoxyalkyl acrylate monomer, and Comparative Example 5 having a low content of alkoxyalkyl acrylate monomer, haze increased under high temperature and high humidity conditions. The cloudiness was confirmed.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Adhesive Tapes (AREA)
  • Adhesives Or Adhesive Processes (AREA)

Abstract

An adhesive sheet to be bonded to a metal surface, which comprises an adhesive layer that is formed of an acrylic adhesive that uses a (meth)acrylic acid ester copolymer. The content of a (meth)acrylic acid alkoxyalkyl ester monomer (A) is 50% by mass or more and the content of a (meth)acrylic acid alkyl ester (B) having an acryl group with 1-4 carbon atoms is 5-45% by mass in the monomer components constituting the (meth)acrylic acid ester copolymer, while the content of a carboxyl group-containing monomer is 1% or less in the monomer components constituting the (meth)acrylic acid ester copolymer. Consequently, the adhesive sheet for metal surface bonding is capable of reducing white turbidity and metal corrosion under high temperature high humidity conditions.

Description

金属面貼付用粘着シートAdhesive sheet for metal surface sticking
　本発明は、金属面に貼り付ける粘着シートに関する。 This invention relates to the adhesive sheet affixed on a metal surface.
　近年、タッチセンサが電子機器に搭載され始めている。電子機器用のタッチセンサには、主に入力時の圧力で検知する抵抗膜方式のタッチパネルと、入力時の人体からの静電気で入力箇所を検知する静電容量方式のタッチパネルが主に搭載されており、入力方法の多機能性から静電容量方式が主流となりつつある。タッチパネルには、透明フィルム基材やガラスに導電層が設けられた透明金属膜が使用されており、静電容量方式のタッチパネルにおいては、当該透明金属膜の金属層表面が、両面粘着シートの粘着剤層表面と接するように固定される。 In recent years, touch sensors have begun to be installed in electronic devices. The touch sensors for electronic devices are mainly equipped with a resistive touch panel that detects the pressure at the time of input and a capacitive touch panel that detects the input location by static electricity from the human body at the time of input. In view of the multi-functionality of the input method, the capacitive method is becoming mainstream. A transparent metal film in which a conductive layer is provided on a transparent film substrate or glass is used for the touch panel, and in the capacitive touch panel, the metal layer surface of the transparent metal film is adhered to a double-sided adhesive sheet. It is fixed so as to be in contact with the surface of the agent layer.
　透明金属膜の金属層は、例えば酸化インジウムスズなど高い透明性と導電性を有する金属を蒸着することで形成されており、当該金属膜の金属層表面に粘着剤層が接するよう両面粘着シートを積層した場合には、両面粘着シートによる金属の酸化反応が起こり、導電機能の低下が起こる問題がある。このため、金属面貼付用の両面粘着シートには高い金属腐食防止性が要請されている。 The metal layer of the transparent metal film is formed by evaporating a highly transparent and conductive metal such as indium tin oxide, and a double-sided pressure-sensitive adhesive sheet is attached so that the pressure-sensitive adhesive layer is in contact with the metal layer surface of the metal film. In the case of lamination, there is a problem that a metal oxidation reaction occurs due to the double-sided pressure-sensitive adhesive sheet and the conductive function is lowered. For this reason, high metal corrosion prevention property is requested | required of the double-sided adhesive sheet for metal surface sticking.
　金属腐食防止性を有する両面粘着シートとしては、粘着剤層に含有する酸成分が金属の腐食の原因であることから、酸成分を含有しない両面粘着シート（例えば、特許文献１～３参照）が提案されている。当該両面粘着シートは、金属を腐食させる要因となる酸成分を含有しない粘着剤層により金属腐食防止性を有するものである。しかし、酸成分を含有しない粘着シートは、粘着剤層の親水性が低下し、高温高湿下で粘着剤層が白濁する問題があった。 As the double-sided pressure-sensitive adhesive sheet having metal corrosion prevention properties, double-sided pressure-sensitive adhesive sheets that do not contain an acid component (see, for example, Patent Documents 1 to 3) because the acid component contained in the pressure-sensitive adhesive layer causes corrosion of the metal. Proposed. The double-sided pressure-sensitive adhesive sheet has metal corrosion prevention properties due to a pressure-sensitive adhesive layer that does not contain an acid component that causes corrosion of the metal. However, the pressure-sensitive adhesive sheet containing no acid component has a problem that the hydrophilicity of the pressure-sensitive adhesive layer is lowered, and the pressure-sensitive adhesive layer becomes cloudy under high temperature and high humidity.
特開２０１０－２１５７９４号公報JP 2010-215794 A 特開２００９－７９２０３号公報JP 2009-79203 A 特開２０１０－２１５９２３号公報JP 2010-215923 A
　本発明が解決しようとする課題は、金属面に対して直接貼り合わせても金属面を腐食させず、また、高温環境下での白濁による視認性の低下が生じ難い粘着シートを提供することにある。 The problem to be solved by the present invention is to provide a pressure-sensitive adhesive sheet that does not corrode the metal surface even when directly bonded to the metal surface, and is less likely to deteriorate in visibility due to white turbidity in a high-temperature environment. is there.
　本発明においては、粘着シートの粘着剤層に、特定量の（メタ）アクリル酸アルコキシアルキルエステル単量体と炭素数１～４のアルキル基を有する（メタ）アクリル酸アルキルエステル単量体を共重合した（メタ）アクリル酸エステル共重合体を用いることで、高温高湿条件下での白濁と金属の腐食を起こさない粘着シートを実現した。 In the present invention, a specific amount of the (meth) acrylic acid alkoxyalkyl ester monomer and the (meth) acrylic acid alkyl ester monomer having an alkyl group having 1 to 4 carbon atoms are used together in the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet. By using a polymerized (meth) acrylic acid ester copolymer, a pressure-sensitive adhesive sheet that does not cause white turbidity and metal corrosion under high temperature and high humidity conditions was realized.
　すなわち本発明は、金属面に貼り合わせる粘着シートであって、前記粘着シートが、（メタ）アクリル酸エステル共重合体を使用したアクリル系粘着剤からなる粘着剤層を有し、前記（メタ）アクリル酸エステル共重合体が、（メタ）アクリル酸アルコキシアルキルエステル単量体（Ａ）及び炭素数が１～４のアクリル基を有する（メタ）アクリル酸アルキルエステル（Ｂ）を単量体成分として含有し、（メタ）アクリル酸エステル共重合体を構成する単量体成分中の前記（メタ）アクリル酸アルコキシアルキルエステル単量体（Ａ）の含有量が５０質量％以上、前記炭素原子数が１～４のアクリル基を有する（メタ）アクリル酸アルキルエステル（Ｂ）の含有量が５～４５質量％であり、（メタ）アクリル酸エステル共重合体を構成する単量体成分中のカルボキシル基含有単量体の含有量が１％以下である金属面貼付用粘着シートを提供するものである。 That is, the present invention is a pressure-sensitive adhesive sheet to be bonded to a metal surface, the pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer made of an acrylic pressure-sensitive adhesive using a (meth) acrylic acid ester copolymer, The acrylic acid ester copolymer comprises (meth) acrylic acid alkoxyalkyl ester monomer (A) and (meth) acrylic acid alkyl ester (B) having an acrylic group having 1 to 4 carbon atoms as monomer components. And the content of the (meth) acrylic acid alkoxyalkyl ester monomer (A) in the monomer component constituting the (meth) acrylic acid ester copolymer is 50% by mass or more, and the number of carbon atoms is The content of the (meth) acrylic acid alkyl ester (B) having 1 to 4 acrylic groups is 5 to 45% by mass, and constitutes a (meth) acrylic acid ester copolymer The content of the carboxyl group-containing monomer in the dimer component is to provide an adhesive sheet for sticking a metal surface is not more than 1%.
　本発明の金属面貼付用粘着シートは、粘着剤層に特定量の（メタ）アクリル酸アルコキシアルキルエステル単量体と炭素数１～４のアルキル基を有する（メタ）アクリル酸アルキルエステル単量体を共重合した（メタ）アクリル酸エステル共重合体が含まれているため、カルボキシル基含有単量体の含有量が少量でも、粘着剤層の親水性が高く、高温高湿条件下で粘着剤層が白濁せず、さらに金属の腐食を防げる。 The pressure-sensitive adhesive sheet for sticking a metal surface of the present invention is a (meth) acrylic acid alkyl ester monomer having a specific amount of a (meth) acrylic acid alkoxyalkyl ester monomer and an alkyl group having 1 to 4 carbon atoms in the pressure-sensitive adhesive layer. (Meth) acrylic acid ester copolymer is included, so even if the content of the carboxyl group-containing monomer is small, the pressure-sensitive adhesive layer is highly hydrophilic and can be used under high temperature and high humidity conditions. The layer does not become cloudy and further prevents corrosion of the metal.
本発明の金属面貼付用粘着シートを適用した画像表示装置の構成例を示す概略図である。It is the schematic which shows the structural example of the image display apparatus to which the adhesive sheet for metal surface sticking of this invention is applied. 本発明の金属面貼付用粘着シートを適用した画像表示装置の構成例を示す概略図である。It is the schematic which shows the structural example of the image display apparatus to which the adhesive sheet for metal surface sticking of this invention is applied. 本発明の金属面貼付用粘着シートを適用した画像表示装置の構成例を示す概略図である。It is the schematic which shows the structural example of the image display apparatus to which the adhesive sheet for metal surface sticking of this invention is applied.
　本発明の金属面貼付用粘着シートは、金属面に貼り合わせる粘着シートであって、前記粘着シートの粘着剤層が、（メタ）アクリル酸アルコキシアルキルエステル単量体（Ａ）と炭素数が１～４のアルキル基を有する（メタ）アクリル酸アルキルエステル単量体（Ｂ）を主たる単量体として含有する（メタ）アクリル酸エステル共重合体からなる粘着剤層であり、前記（メタ）アクリル酸エステル共重合体を構成する単量体成分中の（メタ）アクリル酸アルコキシアルキルエステル単量体（Ａ）の含有量が５０質量％以上、炭素数が１～４のアルキル基を有する（メタ）アクリル酸アルキルエステル単量体（Ｂ）の含有量が５～４５質量％であり、カルボキシル基含有単量体の含有量が１質量％以下の粘着シートである。 The pressure-sensitive adhesive sheet for sticking a metal surface of the present invention is a pressure-sensitive adhesive sheet to be bonded to a metal surface, and the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet has (meth) acrylic acid alkoxyalkyl ester monomer (A) and 1 carbon number. A pressure-sensitive adhesive layer comprising a (meth) acrylic acid ester copolymer containing a (meth) acrylic acid alkyl ester monomer (B) having an alkyl group of 4 to 4 as a main monomer, the (meth) acrylic The content of the (meth) acrylic acid alkoxyalkyl ester monomer (A) in the monomer component constituting the acid ester copolymer is 50% by mass or more and has an alkyl group having 1 to 4 carbon atoms (meta ) A pressure-sensitive adhesive sheet having an acrylic acid alkyl ester monomer (B) content of 5 to 45% by mass and a carboxyl group-containing monomer content of 1% by mass or less.
［（メタ）アクリル酸エステル共重合体］
　本発明の（メタ）アクリル酸エステル共重合体を構成する（メタ）アクリル酸アルコキシアルキルエステル単量体（Ａ）としては、具体的には、アクリル酸２－メトキシエチル、アクリル酸２－エトキシエチル、アクリル酸２メトキシトリエチレングリコール、アクリル酸３－メトキシプロピル、アクリル酸３－エトキシプロピル、アクリル酸４－メトキシブチル、アクリル酸４－エトキシブチルなどが挙げられる。その中でも、特に、アクリル酸２－メトキシエチル、アクリル酸２－エトキシエチルが好ましい。上記単量体を使用することで、粘着剤層に金属膜を固定するために必要な凝集力を付与できる。 [(Meth) acrylic acid ester copolymer]
Specific examples of the (meth) acrylic acid alkoxyalkyl ester monomer (A) constituting the (meth) acrylic acid ester copolymer of the present invention include 2-methoxyethyl acrylate and 2-ethoxyethyl acrylate. , 2-methoxytriethylene glycol acrylate, 3-methoxypropyl acrylate, 3-ethoxypropyl acrylate, 4-methoxybutyl acrylate, 4-ethoxybutyl acrylate, and the like. Of these, 2-methoxyethyl acrylate and 2-ethoxyethyl acrylate are particularly preferable. By using the monomer, cohesive force necessary for fixing the metal film to the pressure-sensitive adhesive layer can be imparted.
　なお、本明細書においてはアクリル酸及びメタアクリル酸を総称して（メタ）アクリル酸と標記し、これらの誘導体についても同様に表記する。 In this specification, acrylic acid and methacrylic acid are collectively referred to as (meth) acrylic acid, and these derivatives are also represented in the same manner.
　（メタ）アクリル酸エステル共重合体を構成する全単量体成分１００質量％に対する（メタ）アクリル酸アルコキシアルキルエステル単量体（Ａ）の含有量は、５０～９０質量％が好ましく、６０～９０質量％がより好ましく、７０～９０質量％がさらに好ましく、７５～８５質量％が特に好ましい。当該範囲内の（メタ）アクリル酸アルコキシアルキルエステル単量体（Ａ）の含有量にすることで、粘着剤層の親水性を高め、高温高湿下でも白濁しない。 The content of the (meth) acrylic acid alkoxyalkyl ester monomer (A) with respect to 100% by mass of all monomer components constituting the (meth) acrylic acid ester copolymer is preferably 50 to 90% by mass, preferably 60 to 90% by mass is more preferable, 70 to 90% by mass is further preferable, and 75 to 85% by mass is particularly preferable. By making the content of the (meth) acrylic acid alkoxyalkyl ester monomer (A) within the range, the hydrophilicity of the pressure-sensitive adhesive layer is increased, and it does not become cloudy even under high temperature and high humidity.
　本発明の（メタ）アクリル酸エステル共重合体を構成する炭素数１～４のアルキル基を有する（メタ）アクリル酸アルキルエステル単量体（Ｂ）としては、上記（メタ）アクリル酸アルコキシアルキルエステル単量体（Ａ）以外の（メタ）アクリル酸アルキルエステル単量体であり、具体的には、エチルアクリレート、アクリル酸ｎ－プロピル、アクリル酸イソプロピル、アクリル酸ｎ－ブチル、アクリル酸ｓｅｃ－ブチル、アクリル酸ｔ－ブチル、メタクリル酸メチル、メタクリル酸エチル、メタクリル酸ｎ－プロピル、メタクリル酸イソプロピル、メタクリル酸ｎ－ブチル、メタクリル酸ｓｅｃ－ブチル、メタクリル酸ｔ－ブチル等が挙げられる。 The (meth) acrylic acid alkyl ester monomer (B) having an alkyl group having 1 to 4 carbon atoms constituting the (meth) acrylic acid ester copolymer of the present invention includes the above (meth) acrylic acid alkoxyalkyl ester. (Meth) acrylic acid alkyl ester monomers other than monomer (A), specifically ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, sec-butyl acrylate Tert-butyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, sec-butyl methacrylate, t-butyl methacrylate and the like.
　そのなかでも、アクリル酸ｎ－ブチルが特に好ましい。アクリル酸ｎ－ブチルを使用することで、金属面に対する高接着性と、高温高湿条件下での耐白濁性が両立できる。 Among them, n-butyl acrylate is particularly preferable. By using n-butyl acrylate, it is possible to achieve both high adhesion to a metal surface and white turbidity resistance under high temperature and high humidity conditions.
　（メタ）アクリル酸エステル共重合体を構成する全単量体成分１００質量％に対する炭素数１～４の（メタ）アクリル酸エステル単量体（Ｂ）の含有量は、５～４５質量％が好ましく、５～３５質量％がより好ましく、５～２５質量％がさらに好ましく、１０～２５質量％が特に好ましい。当該範囲内の（メタ）アクリル酸エステル単量体（Ｂ）の含有量にすることで、金属面に対する高接着性と、高温高湿条件下での耐白濁性が両立できる。 The content of the (meth) acrylic acid ester monomer (B) having 1 to 4 carbon atoms with respect to 100% by mass of all monomer components constituting the (meth) acrylic acid ester copolymer is 5 to 45% by mass. Preferably, it is 5 to 35% by mass, more preferably 5 to 25% by mass, and particularly preferably 10 to 25% by mass. By setting the content of the (meth) acrylic acid ester monomer (B) within the above range, both high adhesion to the metal surface and white turbidity resistance under high temperature and high humidity conditions can be achieved.
　本発明の（メタ）アクリル酸エステル共重合体を構成するカルボキシル基含有単量体としては、特に限定されないが、アクリル酸、メタアクリル酸、イタコン酸、マレイン酸、クロトン酸、アクリル酸ダイマー、エチレンオキサイド変性コハク酸アクリレート等が挙げられる。なかでも汎用性が高いことからアクリル酸が好ましい。 Although it does not specifically limit as a carboxyl group-containing monomer which comprises the (meth) acrylic acid ester copolymer of this invention, Acrylic acid, methacrylic acid, itaconic acid, maleic acid, crotonic acid, acrylic acid dimer, ethylene Examples thereof include oxide-modified succinic acid acrylate. Of these, acrylic acid is preferred because of its high versatility.
　前記カルボキシル基含有単量体の使用量はアクリル共重合体を構成する単量体成分中の１質量％以下であり、０．５質量％以下がさらに好ましく、０．１質量％以下がより好ましく、実質的に含有しないことが特に好ましい。当該範囲内のカルボキシル基含有単量体の含有量にすることで、金属の腐食が防止できる。 The amount of the carboxyl group-containing monomer used is 1% by mass or less in the monomer component constituting the acrylic copolymer, more preferably 0.5% by mass or less, and more preferably 0.1% by mass or less. In particular, it is particularly preferable not to contain it. By setting the content of the carboxyl group-containing monomer within the range, corrosion of the metal can be prevented.
　また、架橋剤と好適に架橋反応させることにより粘着剤層の凝集力を高くするために、架橋剤と反応する官能基を有するビニル単量体を使用することも好ましい。架橋剤と反応する官能基を有するビニル単量体としては、特に限定されないが、アクリル酸２－ヒドロキシエチル、メタクリル酸２－ヒドロキシエチル、アクリル酸４－ヒドロキシブチル等の水酸基含有ビニル単量体等が挙げられる。 It is also preferable to use a vinyl monomer having a functional group that reacts with the crosslinking agent in order to increase the cohesive strength of the pressure-sensitive adhesive layer by suitably crosslinking with the crosslinking agent. The vinyl monomer having a functional group that reacts with the crosslinking agent is not particularly limited, but a hydroxyl group-containing vinyl monomer such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 4-hydroxybutyl acrylate, etc. Is mentioned.
　前記官能基を有するビニル単量体の使用量はアクリル共重合体を構成する単量体成分中の０．１質量％～１０質量％であることが好ましく、０．５～５質量％であることが特に好ましい。 The amount of the vinyl monomer having a functional group used is preferably 0.1% by mass to 10% by mass, and preferably 0.5% by mass to 5% by mass in the monomer component constituting the acrylic copolymer. It is particularly preferred.
　（メタ）アクリル酸エステル共重合体の重量平均分子量Ｍｗは３０万～１６０万であることが好ましく、４０万～１３０万がより好ましく、５０万～１００万がさらに好ましい。（メタ）アクリル酸エステル共重合体の重量平均分子量Ｍｗが当該範囲内だと、金属面に対する接着性と、貼付する金属や表示パネルの凹凸に対する追従性を好適に付与できる。 The weight average molecular weight Mw of the (meth) acrylic acid ester copolymer is preferably 300,000 to 1,600,000, more preferably 400,000 to 1,300,000, and further preferably 500,000 to 1,000,000. When the weight average molecular weight Mw of the (meth) acrylic acid ester copolymer is within the above range, the adhesiveness to the metal surface and the followability to the unevenness of the metal to be attached and the display panel can be suitably imparted.
　また、（メタ）アクリル酸エステル共重合体の分子量分布（重量平均分子量Ｍｗ／数平均分子量Ｍｎ）は１０～５０であることが好ましく、１０～３０がより好ましく、１０～２０がさらに好ましい。（メタ）アクリル酸エステル共重合体の分子量分布（重量平均分子量Ｍｗ／数平均分子量Ｍｎ）が当該範囲内だと、貼付する金属や表示パネルの凹凸に対する追従性を付与でき、表示画面部分に気泡を残しにくく、さらに金属面からの剥がれを抑制できる。 The molecular weight distribution (weight average molecular weight Mw / number average molecular weight Mn) of the (meth) acrylate copolymer is preferably 10 to 50, more preferably 10 to 30, and still more preferably 10 to 20. When the molecular weight distribution (weight average molecular weight Mw / number average molecular weight Mn) of the (meth) acrylic acid ester copolymer is within this range, it is possible to provide follow-up to the unevenness of the metal to be affixed and the display panel, and there are bubbles in the display screen portion. Is less likely to remain, and further peeling from the metal surface can be suppressed.
　なお、本発明では、当該カルボキシル基含有（メタ）アクリル酸エステル共重合体（Ａ）の重量平均分子量Ｍｗは、ゲルパーミエーションクロマトグラフ（ＧＰＣ）により測定することができる。より具体的には、ＧＰＣ測定装置として、東ソー株式会社製「ＳＣ８０２０」を用いて、ポリスチレン換算値により、次のＧＰＣ測定条件で測定して求めることができる。
（ＧＰＣの測定条件）
・サンプル濃度：０．５質量％（テトラヒドロフラン溶液）
・サンプル注入量：１００μＬ
・溶離液：テトラヒドロフラン（ＴＨＦ）
・流速：１．０ｍＬ／ｍｉｎ
・カラム温度（測定温度）：４０℃
・カラム：東ソー株式会社製「ＴＳＫｇｅｌ　ＧＭＨＨＲ－Ｈ」
・検出器：示差屈折 In the present invention, the weight average molecular weight Mw of the carboxyl group-containing (meth) acrylic acid ester copolymer (A) can be measured by gel permeation chromatography (GPC). More specifically, as a GPC measurement device, “SC8020” manufactured by Tosoh Corporation can be used to measure and obtain the following GPC measurement conditions based on polystyrene conversion values.
(GPC measurement conditions)
Sample concentration: 0.5% by mass (tetrahydrofuran solution)
Sample injection volume: 100 μL
・ Eluent: Tetrahydrofuran (THF)
・ Flow rate: 1.0 mL / min
Column temperature (measurement temperature): 40 ° C
・ Column: “TSKgel GMHHR-H” manufactured by Tosoh Corporation
・ Detector: Differential refraction
　本発明に使用する（メタ）アクリル酸エステル共重合体の重合方法は特に限定されず、公知の各種重合方法を適宜使用でき、溶液重合法、乳化重合法、塊状重合法等の熱重合法、光や放射線等の活性エネルギー線を照射して行う重合方法等を採用することができる。作業性や品質安定性等の観点からは、溶液重合法を好ましく採用することができ、モノマー成分の全量を一度に反応容器に供給する一括仕込み方式、連続又は分割供給する滴下方式等のいずれであってもよい。 The polymerization method of the (meth) acrylic acid ester copolymer used in the present invention is not particularly limited, and various known polymerization methods can be used as appropriate. Thermal polymerization methods such as solution polymerization method, emulsion polymerization method, bulk polymerization method, A polymerization method performed by irradiating active energy rays such as light and radiation can be employed. From the viewpoint of workability, quality stability, etc., a solution polymerization method can be preferably adopted, and any of a batch charging method in which the entire amount of monomer components are supplied to the reaction vessel at once, a dropping method in which continuous or divided supply is used, etc. There may be.
　溶液重合に用いる溶媒としては、溶液重合に使用される各種有機溶媒を使用でき、なかでも非トルエン系有機溶媒の使用が好ましい。好ましい有機溶媒としては、酢酸エチル、ヘキサン、シクロヘキサン、メチルシクロヘキサン、イソプロピルアルコール等が例示される。他の好ましく使用され得る有機溶媒としては、１－ブタノール、セカンダリーブタノール、ターシャリーブタノール、ターシャリーブチルメチルエーテル、メチルエチルケトン、アセチルアセトン、１，２－ジクロロエタン等が例示される。 As the solvent used for the solution polymerization, various organic solvents used for the solution polymerization can be used, and among them, the use of a non-toluene organic solvent is preferable. Examples of preferable organic solvents include ethyl acetate, hexane, cyclohexane, methylcyclohexane, isopropyl alcohol and the like. Examples of other organic solvents that can be preferably used include 1-butanol, secondary butanol, tertiary butanol, tertiary butyl methyl ether, methyl ethyl ketone, acetylacetone, 1,2-dichloroethane and the like.
［粘着剤組成物］
　本発明の金属面貼付用粘着シートの粘着剤層を形成する粘着剤組成物は、上記（メタ）アクリル酸エステル共重合体を含有する粘着剤組成物であり、当該組成物中には、上記共重合体以外の成分として、粘着剤層の凝集力を上げるために、架橋剤を含有することが好ましい。 [Adhesive composition]
The pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet for metal surface sticking of the present invention is a pressure-sensitive adhesive composition containing the above (meth) acrylic acid ester copolymer, As a component other than the copolymer, it is preferable to contain a crosslinking agent in order to increase the cohesive strength of the pressure-sensitive adhesive layer.
　使用する架橋剤としては、イソシアネート系架橋剤、エポキシ系架橋剤、キレート系架橋剤、アジリン系架橋剤、多官能アクリレート系等が挙げられる。その中でも、（メタ）アクリル系共重合体の成分との反応性に富むイソシアネート系架橋剤が好ましい。 Examples of the crosslinking agent used include isocyanate crosslinking agents, epoxy crosslinking agents, chelating crosslinking agents, azirine crosslinking agents, and polyfunctional acrylates. Among these, an isocyanate-based crosslinking agent rich in reactivity with the components of the (meth) acrylic copolymer is preferable.
　当該粘着シートの粘着剤層に添加する架橋剤の配合量は、０．０５～２質量部が好ましく、０．０７～１．５質量部がより好ましく、０．１～１質量部がさらに好ましい。当該範囲の架橋剤の含有量にすることで、粘着剤層のゲル分率を好適な範囲に調整しやすい。 The amount of the crosslinking agent added to the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet is preferably 0.05 to 2 parts by weight, more preferably 0.07 to 1.5 parts by weight, and still more preferably 0.1 to 1 part by weight. . By setting the content of the crosslinking agent in this range, it is easy to adjust the gel fraction of the pressure-sensitive adhesive layer to a suitable range.
　本発明の粘着剤組成物は、上記（メタ）アクリル酸エステル共重合体及び架橋剤が溶媒に溶解又は分散した粘着剤組成物であることが好ましく、当該溶媒としては、上記溶液重合に用いる溶媒と同様の溶媒を好ましく使用できる。 The pressure-sensitive adhesive composition of the present invention is preferably a pressure-sensitive adhesive composition in which the (meth) acrylic acid ester copolymer and the crosslinking agent are dissolved or dispersed in a solvent, and the solvent is a solvent used for the solution polymerization. The same solvent as can be preferably used.
　本発明の粘着剤組成物には、上記以外に、必要に応じて、他の一般的な添加剤、例えば、紫外線吸収剤、光安定剤、老化防止剤、剥離調整剤、粘着付与剤、可塑剤、軟化剤、充填剤、着色剤（顔料や染料など）、界面活性剤などが含まれていてもよい。 In addition to the above, the pressure-sensitive adhesive composition of the present invention may contain other general additives such as ultraviolet absorbers, light stabilizers, anti-aging agents, release modifiers, tackifiers, plasticizers as necessary. Agents, softeners, fillers, colorants (such as pigments and dyes), surfactants, and the like may be included.
［金属面貼付用粘着シート］
　本発明の金属面貼付用粘着シートは、粘着剤層として、上記粘着剤組成物からなる粘着剤層を有することで、高温高湿条件下での粘着剤層の白濁と金属の腐食を抑制できる。 [Adhesive sheet for metal surfaces]
The pressure-sensitive adhesive sheet for metal surface sticking of the present invention can suppress the cloudiness of the pressure-sensitive adhesive layer and corrosion of the metal under high-temperature and high-humidity conditions by having the pressure-sensitive adhesive layer made of the above-mentioned pressure-sensitive adhesive composition as the pressure-sensitive adhesive layer. .
　本発明の金属面貼付用粘着シートは、フィルム基材を有するものであっても、フィルム基材を有さず粘着剤層のみからなる粘着シートであってもよい。また、粘着剤層は単一層からなるものであっても複数層が積層されていてもよい。また、使用態様に応じて、片面粘着シートの形態であっても両面粘着シートの形態であってもよい。 The pressure-sensitive adhesive sheet for sticking a metal surface of the present invention may be a pressure-sensitive adhesive sheet having only a pressure-sensitive adhesive layer without having a film base material. Moreover, even if the adhesive layer consists of a single layer, multiple layers may be laminated | stacked. Moreover, according to a use aspect, the form of a single-sided adhesive sheet or the form of a double-sided adhesive sheet may be sufficient.
　本発明の粘着シートを部品間の固定、例えば、画像表示装置表面の表面保護パネルと、ＩＴＯフィルム又はガラス等の金属面表面を有する部材との固定、あるいは、金属面表面を有する部材同士を固定する部品間固定用粘着シートとして使用する場合には、両面粘着シートの形態を好ましく使用でき、なかでも、透明性の確保や、形状追従性の観点からは、基材を有さず、粘着剤層のみからなる粘着シートであることが好ましい。当該形態の両面粘着シートは、一方の部材が印刷段差を有する表面保護パネル等の表面凹凸形状を有する部材の場合に特に好適である。また、表面保護パネルとＩＴＯガラスが一体化されたパネルや、表面保護パネルの表面がＩＴＯ処理されたパネルの割れ防止や、割れた際の飛散防止のための飛散防止用粘着シートとして使用する場合には、フィルム基材を有する粘着シートの形態を好ましく使用でき、特に一面にハードコート層が設けられたフィルム基材の片面に粘着剤層が設けられた片面粘着シートの形態を好ましく使用できる。 Fixing the adhesive sheet of the present invention between components, for example, fixing a surface protection panel on the surface of an image display device and a member having a metal surface such as ITO film or glass, or fixing members having metal surfaces. When using as a pressure-sensitive adhesive sheet for fixing between parts, the form of a double-sided pressure-sensitive adhesive sheet can be preferably used, and in particular, from the viewpoint of ensuring transparency and shape followability, it does not have a substrate, and is a pressure-sensitive adhesive It is preferable that it is an adhesive sheet which consists only of layers. The double-sided pressure-sensitive adhesive sheet in this form is particularly suitable for a member having an uneven surface shape such as a surface protection panel in which one member has a printed step. Also, when used as an anti-scattering adhesive sheet for preventing cracking of panels in which the surface protection panel and ITO glass are integrated, or for the surface of the surface protection panel being treated with ITO, and for preventing scattering when cracked The form of the pressure-sensitive adhesive sheet having a film base can be preferably used, and the form of a single-sided pressure-sensitive adhesive sheet in which a pressure-sensitive adhesive layer is provided on one side of a film base provided with a hard coat layer on one side can be preferably used.
　本発明の金属面貼付用粘着シートが、フィルム基材を有する場合には、当該基材として透明フィルム基材を使用できる。当該透明基材としては、例えば、ポリエチレンテレフタレート、ポリブチレンテレフタレート、ポリエチレンナフタレート、ポリエチレンフィルム、ポリプロピレンフィルム、セロファン、ジアセチルセルロースフィルム、トリアセチルセルロースフィルム、アセチルセルロースブチレートフィルム、ポリ塩化ビニルフィルム、ポリ塩化ビニリデンフィルム、ポリビニルアルコールフィルム、エチレン－酢酸ビニル共重合体フィルム、ポリスチレンフィルム、ポリカーボネートフィルム、ポリメチルペンテンフィルム、ポリスルホンフィルム、ポリエーテルエーテルケトンフィルム、ポリエーテルスルホンフィルム、ポリエーテルイミドフィルム、ポリイミドフィルム、フッソ樹脂フィルム、ナイロンフィルム、アクリル樹脂フィルム等を挙げることができる。なかでも、透明性、平滑性に優れたポリエチレンテレフタレートが好ましい。 When the pressure-sensitive adhesive sheet for sticking a metal surface of the present invention has a film substrate, a transparent film substrate can be used as the substrate. As the transparent substrate, for example, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyethylene film, polypropylene film, cellophane, diacetyl cellulose film, triacetyl cellulose film, acetyl cellulose butyrate film, polyvinyl chloride film, polyvinyl chloride Vinylidene film, polyvinyl alcohol film, ethylene-vinyl acetate copolymer film, polystyrene film, polycarbonate film, polymethylpentene film, polysulfone film, polyetheretherketone film, polyethersulfone film, polyetherimide film, polyimide film, fluorine Resin film, nylon film, acrylic resin film, etc. Rukoto can. Of these, polyethylene terephthalate having excellent transparency and smoothness is preferable.
　本発明の金属面貼付用粘着シートに使用するフィルム基材には、粘着剤層との密着性を向上させる目的で、サンドブラスト法や溶剤処理法などによる表面の凹凸化処理、あるいはコロナ放電処理、クロム酸処理、火炎処理、熱風処理、オゾン・紫外線照射処理などの表面の酸化処理などの表面処理を施すことができる。 The film substrate used for the adhesive sheet for sticking a metal surface of the present invention has a surface unevenness treatment by a sandblasting method or a solvent treatment method, or a corona discharge treatment, for the purpose of improving the adhesion with the adhesive layer. Surface treatment such as surface oxidation treatment such as chromic acid treatment, flame treatment, hot air treatment, ozone / ultraviolet irradiation treatment and the like can be performed.
　本発明の金属面貼付用粘着シートのフィルム基材は、生産工程中に混入する傷や打痕などの外観欠点を防ぐため、少なくとも片面にハードコート層を有するハードコートフィルムとすることも好ましい。中でも、アクリル樹脂を含有するハードコート層が好ましい。アクリル樹脂を含有することで、ハードコート面に対する接着性を確保できる。また、当該ハードコートフィルムの片面に粘着剤層が設けられた金属面貼付用粘着シートは、飛散防止用粘着シートとして好適に使用できる。 The film substrate of the pressure-sensitive adhesive sheet for sticking a metal surface of the present invention is preferably a hard coat film having a hard coat layer on at least one surface in order to prevent appearance defects such as scratches and dents mixed during the production process. Among these, a hard coat layer containing an acrylic resin is preferable. By containing the acrylic resin, it is possible to ensure adhesion to the hard coat surface. Moreover, the adhesive sheet for metal surface sticking in which the adhesive layer was provided in the single side | surface of the said hard coat film can be used conveniently as an adhesive sheet for scattering prevention.
　本発明の金属面貼付用粘着シートが、ハードコートフィルムの片面に粘着剤層が設けられた金属面貼付用粘着シートであり、当該粘着シートを飛散防止用粘着シートとして使用する場合には、ハードコートフィルムのハードコート層表面の表面鉛筆硬度がＢ以上、好ましくはＦ以上であることが好ましい。また、ハードコート層の厚さを１～５μｍとすることが好ましい。 The pressure-sensitive adhesive sheet for sticking a metal surface of the present invention is a pressure-sensitive adhesive sheet for sticking a metal surface provided with a pressure-sensitive adhesive layer on one side of a hard coat film, and when the pressure-sensitive adhesive sheet is used as a pressure-sensitive adhesive sheet for preventing scattering, It is preferable that the surface pencil hardness of the hard coat layer surface of the coat film is B or more, preferably F or more. Further, the thickness of the hard coat layer is preferably 1 to 5 μm.
　本発明の金属面貼付用粘着シートの粘着剤層は、トルエン中に２４時間浸漬した際の下記式で表されるゲル分率が、３０～８０質量％であることが好ましく、３０～７０質量％であるのがより好ましく、３５～５５質量％が最も好ましい。粘着剤層のゲル分率が上記の範囲内だと、金属面の固定において経時での剥がれを抑制しやすく、また、貼付する金属や表示パネルの凹凸に対する追従性を付与でき、表示画面部分に気泡を残しにくい。
　ゲル分率（質量％）＝［（粘着剤層のトルエン浸漬後質量）／（粘着剤層のトルエン浸漬前質量）］×１００ The pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet for metal surface sticking according to the present invention preferably has a gel fraction represented by the following formula of 30 to 80% by mass when immersed in toluene for 24 hours, preferably 30 to 70% by mass. % Is more preferable, and 35 to 55% by mass is most preferable. When the gel fraction of the pressure-sensitive adhesive layer is within the above range, it is easy to suppress peeling over time in fixing the metal surface, and it is possible to give followability to the unevenness of the metal to be attached and the display panel, and to the display screen part It is hard to leave bubbles.
Gel fraction (% by mass) = [(mass after immersion of the adhesive layer in toluene) / (mass before adhesion of the adhesive layer in toluene)] × 100
　本発明の金属面貼付用粘着シートの粘着剤層は、周波数１Ｈｚで測定される動的粘弾性スペクトルの７０℃の貯蔵弾性率は、貯蔵弾性率が４．０×１０４～９．０×１０５の範囲に含まれることが好ましく、４．０×１０４～８．０×１０４がより好ましく、４．０×１０４～７．０×１０４が最も好ましい。貯蔵弾性率がこの範囲に含まれることで、段差部分に追従する流動性と反りによる剥がれの抑制を両立できる。 The pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet for attaching a metal surface of the present invention has a storage elastic modulus of 4.0 × 10 4 to 9.0 × as a storage elastic modulus at 70 ° C. of a dynamic viscoelastic spectrum measured at a frequency of 1 Hz. It is preferably included in the range of 10 5 , more preferably 4.0 × 10 4 to 8.0 × 10 4, and most preferably 4.0 × 10 4 to 7.0 × 10 4 . By including the storage elastic modulus within this range, it is possible to achieve both fluidity following the stepped portion and suppression of peeling due to warpage.
　本発明における粘着剤層の動的粘弾性は、粘弾性試験機（レオメトリックス社製、商品名：アレス２ＫＳＴＤ）を用いて、同試験機の測定部である平行円盤の間に試験片を挟み込み、周波数１Ｈｚでの貯蔵弾性率（Ｇ’）と損失弾性率（Ｇ”）を測定することで得られる。試験片は厚み０．５～２．５ｍｍの粘着剤を単独で平行円盤の間に挟んでも良いが、基材と粘着剤の積層体を幾重にも重ねて平行円盤の間に挟んでも良い。なお、後者の場合は粘着剤のみの厚さが前記の範囲となるように調整する。 The dynamic viscoelasticity of the pressure-sensitive adhesive layer in the present invention is obtained by sandwiching a test piece between parallel disks, which are measuring parts of the tester, using a viscoelasticity tester (manufactured by Rheometrics, trade name: Ares 2KSTD). , Obtained by measuring the storage elastic modulus (G ′) and loss elastic modulus (G ″) at a frequency of 1 Hz. However, in the latter case, the thickness of the pressure-sensitive adhesive is adjusted to be in the above-mentioned range. .
　本発明の金属面貼付用粘着シートの透明性は、全光線透過率が８０％以上、ヘイズが１．０％以下であることが好ましく、全光線透過率が９０％以上、ヘイズが０．５％以下であることがより好ましい。透明導電膜の透明性が上記範囲内だと、当該粘着フィルムを使用されたタッチパネル装置搭載ディスプレイの透明性が保たれやすい。 The transparency of the pressure-sensitive adhesive sheet for sticking a metal surface of the present invention is preferably such that the total light transmittance is 80% or more and the haze is 1.0% or less, the total light transmittance is 90% or more, and the haze is 0.5. % Or less is more preferable. When the transparency of the transparent conductive film is within the above range, the transparency of the display equipped with the touch panel device using the adhesive film is easily maintained.
　本発明の金属面貼付用粘着シートが貼付される金属は、特に限定されないが、具体的には、酸化インジウムスズ、酸化インジウム、酸化スズ、酸化亜鉛、酸化カドミウム、酸化ガリウム、酸化チタンなどが挙げられる。 The metal to which the pressure-sensitive adhesive sheet for metal surface application of the present invention is attached is not particularly limited, and specific examples include indium tin oxide, indium oxide, tin oxide, zinc oxide, cadmium oxide, gallium oxide, titanium oxide and the like. It is done.
　本発明の金属面貼付用粘着シートの温度２３℃、相対湿度５０％ＲＨの環境下で、金属に対し、２ｋｇローラーを使用して圧着回数一往復で圧着し、１時間静置した後の３００ｍｍ／ｍｉｎでの１８０°剥離接着力は、金属に対してそれぞれ５～２０Ｎ／２５ｍｍであることが好ましい。上記範囲内だと、透明導電膜の固定において端面からの剥がれを抑制しやすく、また、製造工程での貼り合わせ不良品において粘着シートの剥離が可能となる。 The pressure-sensitive adhesive sheet for sticking a metal surface of the present invention is subjected to one-time reciprocation using a 2 kg roller in a temperature of 23 ° C. and a relative humidity of 50% RH, and left for 1 hour. The 180 ° peel adhesion at 300 mm / min is preferably 5 to 20 N / 25 mm for each metal. Within the above range, it is easy to suppress peeling from the end face in fixing the transparent conductive film, and the pressure-sensitive adhesive sheet can be peeled in a poorly bonded product in the manufacturing process.
　本発明の金属面貼付用粘着シートの厚みは、使用する態様により適宜選択すればよいが、５～５００μｍであることが好ましい。なかでも、平滑面に接着する場合には、１０～２５０μｍに調整することで、タッチパネル装置を薄型化しやすい。また、段差や凹凸を有する面に貼り付ける場合には、粘着剤層の厚さを２０μｍ以上とすることが好ましく、２５～１５０μｍとすることが特に好ましい。 The thickness of the pressure-sensitive adhesive sheet for sticking a metal surface of the present invention may be appropriately selected depending on the mode of use, but is preferably 5 to 500 μm. In particular, when bonding to a smooth surface, it is easy to make the touch panel device thinner by adjusting to 10 to 250 μm. Further, when affixing to a surface having a step or unevenness, the thickness of the pressure-sensitive adhesive layer is preferably 20 μm or more, and particularly preferably 25 to 150 μm.
　本発明の金属面貼付用粘着シートは、一般的に使用されている方法で作成できる。例えば、フィルム基材または離型シート上に粘着剤層を形成して製造することができる。具体的には、粘着剤の組成物を基材フィルムに直接塗布し乾燥または硬化・重合するか、或いは、いったん離型シート上に塗布し、乾燥または硬化・重合し、粘着剤層を形成後、同様にして離型シート上に作成した粘着剤層又は基材フィルムに貼り合わせる方法などにより製造できる。 The pressure-sensitive adhesive sheet for attaching a metal surface of the present invention can be prepared by a generally used method. For example, it can be produced by forming an adhesive layer on a film substrate or a release sheet. Specifically, the adhesive composition is directly applied to the base film and dried or cured / polymerized, or once applied on the release sheet and dried / cured / polymerized to form an adhesive layer. Similarly, it can be produced by a method of bonding to an adhesive layer or a base film prepared on a release sheet.
[使用形態]
　本発明の金属面貼付用粘着シートは、金属面を腐食させず、良好な耐白化性を有することから、ガラスやフィルムの表面に酸化インジウムスズ（ＩＴＯ）が設けられたＩＴＯガラスやＩＴＯフィルム、あるいは、ガラスやフィルムの表面に銀や銅の配線が設けられた金属配線フィルム等の金属面表面を有する部材を固定する際に好適に使用できる。中でも、高い透明性が求められ、かつ、安定した導電性が求められる金属面表面を有する部材の固定に好適に使用できる。また、本発明の金属面貼付用粘着シートは、良好な段差追従性を実現できることから、固定する部材が表面凹凸形状を有する部材、例えば印刷段差が設けられた部材であっても好適に適用できる。 [Usage form]
The adhesive sheet for sticking a metal surface of the present invention does not corrode the metal surface and has good whitening resistance, so that ITO glass or ITO film provided with indium tin oxide (ITO) on the surface of the glass or film, Or it can use conveniently, when fixing the member which has metal surface surfaces, such as a metal wiring film by which the wiring of silver or copper was provided in the surface of glass or a film. Especially, it can use suitably for fixation of the member which has a metal surface surface for which high transparency is calculated | required and the stable electroconductivity is calculated | required. In addition, since the pressure-sensitive adhesive sheet for sticking a metal surface of the present invention can realize good step followability, the member to be fixed can be suitably applied even if it is a member having a surface uneven shape, for example, a member provided with a printing step. .
　本発明の金属面貼付用粘着シートを適用する好適な構成例としては、例えば、高透明性と安定した導電性が要求される、電子機器の画像表示部に使用されるタッチセンサーでの、ＩＴＯが片面に蒸着されたポリエチレンテレフタレートフィルムと表面保護パネルの固定や、ＩＴＯが片面に蒸着されたポリエチレンテレフタレートフィルム同士の固定に好適に使用できる。このような構成の画像表示装置の具体例としては、図１に示したような構成を好ましく例示できる。図１における適用例は、印刷段差３を有する表面保護パネル２と、透明樹脂フィルム４ａ上にＩＴＯ表面４ｂを有するＩＴＯフィルム４とを、基材レスの本発明の金属面貼付用粘着シート１により固定する用途であり、本発明の粘着シートは当該用途に好適に使用できる。また、ＬＣＤモジュール等の画像表示モジュール６を筐体５内に有し、当該筐体とＩＴＯフィルム４’の透明樹脂フィルム４ａ側とが粘着テープや接着テープ等の接着部材７により固定され、当該ＩＴＯフィルム４’のＩＴＯ表面４ｂ’と、上記のＩＴＯフィルム４の透明樹脂フィルム４ａ表面とを、基材レスの本発明の金属面貼付用粘着シート’１により固定する用途にも好適に使用できる。 As a suitable configuration example to which the pressure-sensitive adhesive sheet for metal surface application of the present invention is applied, for example, ITO in a touch sensor used in an image display unit of an electronic device, which requires high transparency and stable conductivity, is required. Can be suitably used for fixing a polyethylene terephthalate film deposited on one side and a surface protection panel, or fixing between polyethylene terephthalate films deposited on one side. As a specific example of the image display device having such a configuration, the configuration as shown in FIG. 1 can be preferably exemplified. In the application example in FIG. 1, the surface protection panel 2 having the printing step 3 and the ITO film 4 having the ITO surface 4 b on the transparent resin film 4 a are applied to the baseless pressure-sensitive adhesive sheet 1 for attaching a metal surface of the present invention. The adhesive sheet of the present invention can be suitably used for such applications. In addition, an image display module 6 such as an LCD module is provided in the housing 5, and the housing and the transparent resin film 4 a side of the ITO film 4 ′ are fixed by an adhesive member 7 such as an adhesive tape or an adhesive tape. The ITO surface 4b 'of the ITO film 4' and the transparent resin film 4a surface of the ITO film 4 can be suitably used for the purpose of fixing by the adhesive sheet '1 for sticking a metal surface of the present invention without a substrate. .
　さらに、電子機器の画像表示部に使用されるタッチセンサーでの、酸価インジウムスズが片面に蒸着されたガラスと表面保護パネルの固定、またはガラス破損時の飛散防止を目的とした粘着フィルムとして好適に使用できる。このような構成の画像表示装置の具体例としては、図２及び図３に示した構成を好ましく例示できる。図２における適用例は、一面がＩＴＯ処理されたＩＴＯ表面１４を有し、当該表面に印刷段差１３が設けられた表面保護パネル１２のＩＴＯ表面１４に、当該表面保護パネルの飛散防止用粘着シートとして、ハードコートフィルム１６の一面に粘着剤層１５を有する本発明の金属面貼付用粘着シート１１を適用する例である。当該構成においては、金属面貼付用粘着シート１１のハードコートフィルム１６と、ＬＣＤモジュール等の画像表示モジュール１８を有する筐体１７とが、接着部材１９により固定される。また、図３における適用例は、印刷段差２３を有する表面保護パネル２２と、透明ガラス２４ａ上にＩＴＯ表面２４ｂ及び２４ｃを有するＩＴＯガラス２４とを、基材レスの本発明の金属面貼付用粘着シート２１により固定する用途であり、上記図１の態様と同様に本発明の粘着シートを好適に適用できる。さらに、当該ＩＴＯガラス２４の飛散防止用粘着シートとして、ハードコートフィルム２５の一面に粘着剤層２６を有する本発明の金属面貼付用粘着シート２１’を適用することもできる。当該構成においては、図２と同様に金属面貼付用粘着シート２１’のハードコートフィルム２５と、ＬＣＤモジュール等の画像表示モジュール２８を有する筐体２７とが、接着部材２９により固定される。 Furthermore, it is suitable as a pressure-sensitive adhesive film for the purpose of fixing glass and surface protection panels with acid value indium tin deposited on one side, or preventing scattering when glass is broken, in touch sensors used in image display parts of electronic devices. Can be used for As a specific example of the image display device having such a configuration, the configuration shown in FIGS. 2 and 3 can be preferably exemplified. The application example in FIG. 2 has an ITO surface 14 on which one surface is treated with ITO, and an adhesive sheet for preventing scattering of the surface protection panel on the ITO surface 14 of the surface protection panel 12 provided with a printing step 13 on the surface. As an example, the pressure-sensitive adhesive sheet 11 for sticking a metal surface of the present invention having the pressure-sensitive adhesive layer 15 on one surface of the hard coat film 16 is applied. In this configuration, the hard coat film 16 of the adhesive sheet 11 for attaching a metal surface and the casing 17 having an image display module 18 such as an LCD module are fixed by an adhesive member 19. Further, in the application example in FIG. 3, the surface protection panel 22 having the printing step 23 and the ITO glass 24 having the ITO surfaces 24b and 24c on the transparent glass 24a are bonded to the substrate-less adhesive for metal surface of the present invention. It is a use fixed by the sheet | seat 21, and the adhesive sheet of this invention can be applied suitably similarly to the aspect of the said FIG. Furthermore, as the pressure-sensitive adhesive sheet for preventing scattering of the ITO glass 24, the pressure-sensitive adhesive sheet 21 'for attaching a metal surface of the present invention having the pressure-sensitive adhesive layer 26 on one surface of the hard coat film 25 can be applied. In this configuration, the hard coat film 25 of the metal surface sticking adhesive sheet 21 ′ and the housing 27 having the image display module 28 such as an LCD module are fixed by the adhesive member 29 as in FIG. 2.
　以下に実施例および比較例により本発明をより具体的に説明する。
＜アクリル共重合体（１）＞
　アクリル共重合体の調製攪拌機、寒流冷却器、温度計、滴下漏斗及び窒素ガス導入口を備えた反応容器に、アクリル酸２－メトキシエチル７５質量％、アクリル酸ｎ－ブチル２４質量％、アクリル酸ヒドロキシエチル１質量％と重合開始剤として２，２’－アゾビスイソブチルニトリル０．２部とを酢酸エチル１００質量％に溶解し、窒素置換後、８０℃で８時間重合して重量平均分子量７０万のアクリル酸エステル共重合体（１）を得た。 Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples.
<Acrylic copolymer (1)>
Preparation of acrylic copolymer In a reaction vessel equipped with a stirrer, cold flow cooler, thermometer, dropping funnel and nitrogen gas inlet, 2-methoxyethyl acrylate 75% by mass, n-butyl acrylate 24% by mass, acrylic acid 1% by mass of hydroxyethyl and 0.2 part of 2,2′-azobisisobutylnitrile as a polymerization initiator are dissolved in 100% by mass of ethyl acetate, and after nitrogen substitution, polymerized at 80 ° C. for 8 hours to give a weight average molecular weight of 70 Ten thousand acrylic acid ester copolymers (1) were obtained.
＜アクリル共重合体（２）＞
　アクリル酸２－メトキシエチルを８５質量％、アクリル酸ｎ－ブチルを１４質量％とする以外は、アクリル酸エステル共重合体（１）と同様にして、重量平均分子量７０万のアクリル酸エステル共重合体（２）を得た。 <Acrylic copolymer (2)>
Acrylate ester copolymer having a weight average molecular weight of 700,000 was obtained in the same manner as in the acrylate ester copolymer (1) except that 2-methoxyethyl acrylate was 85% by mass and n-butyl acrylate was 14% by mass. Combined (2) was obtained.
＜アクリル共重合体（３）＞
　アクリル共重合体の調製攪拌機、寒流冷却器、温度計、滴下漏斗及び窒素ガス導入口を備えた反応容器に、アクリル酸２－メトキシエチル７０質量％、アクリル酸２エチルヘキシル２９質量％、アクリル酸ヒドロキシエチル１質量％と重合開始剤として２，２’－アゾビスイソブチルニトリル０．２部とを酢酸エチル１００質量％に溶解し、窒素置換後、８０℃で８時間重合して重量平均分子量１００万のアクリル酸エステル共重合体（３）を得た。 <Acrylic copolymer (3)>
Preparation of acrylic copolymer In a reaction vessel equipped with a stirrer, cold flow cooler, thermometer, dropping funnel and nitrogen gas inlet, 2-methoxyethyl acrylate 70% by mass, 2-ethylhexyl acrylate 29% by mass, hydroxy acrylate 1% by mass of ethyl and 0.2 part of 2,2′-azobisisobutylnitrile as a polymerization initiator are dissolved in 100% by mass of ethyl acetate, and after substitution with nitrogen, polymerization is carried out at 80 ° C. for 8 hours to give a weight average molecular weight of 1,000,000. Acrylic ester copolymer (3) was obtained.
＜アクリル共重合体（４）＞
　アクリル酸２－メトキシエチルを５０質量％、アクリル酸ｎ－ブチルを４９質量％とする以外は、アクリル酸エステル共重合体（１）と同様にして、重量平均分子量１００万のアクリル酸エステル共重合体（４）を得た。 <Acrylic copolymer (4)>
Acrylate ester copolymer having a weight average molecular weight of 1,000,000 is the same as that of the acrylate ester copolymer (1) except that 50% by mass of 2-methoxyethyl acrylate and 49% by mass of n-butyl acrylate are used. Combined (4) was obtained.
＜アクリル共重合体（５）＞
　アクリル共重合体の調製攪拌機、寒流冷却器、温度計、滴下漏斗及び窒素ガス導入口を備えた反応容器にアクリル酸ｎ－ブチル８０質量％、メタクリル酸メチル１９質量％、アクリル酸ヒドロキシエチル１質量％と重合開始剤として２，２’－アゾビスイソブチルニトリル０．２部とを酢酸エチル１００質量％に溶解し、窒素置換後、８０℃で８時間重合して重量平均分子量８０万のアクリル酸エステル共重合体（５）を得た。 <Acrylic copolymer (5)>
Preparation of acrylic copolymer In a reaction vessel equipped with a stirrer, cold flow cooler, thermometer, dropping funnel and nitrogen gas inlet, n-butyl acrylate 80% by mass, methyl methacrylate 19% by mass, hydroxyethyl acrylate 1% by mass % And 0.22 part of 2,2′-azobisisobutylnitrile as a polymerization initiator are dissolved in 100% by mass of ethyl acetate, purged with nitrogen, polymerized at 80 ° C. for 8 hours, and acrylic acid having a weight average molecular weight of 800,000 An ester copolymer (5) was obtained.
＜アクリル共重合体（６）＞
　アクリル共重合体の調製攪拌機、寒流冷却器、温度計、滴下漏斗及び窒素ガス導入口を備えた反応容器にアクリル酸ｎ－ブチル８０質量％、アクリル酸１９質量％、アクリル酸ヒドロキシエチル１質量％と重合開始剤として２，２’－アゾビスイソブチルニトリル０．２部とを酢酸エチル１００質量％に溶解し、窒素置換後、８０℃で８時間重合して重量平均分子量７０万のアクリル酸エステル共重合体（６）を得た。 <Acrylic copolymer (6)>
Preparation of acrylic copolymer In a reaction vessel equipped with a stirrer, cold flow condenser, thermometer, dropping funnel and nitrogen gas inlet, n-butyl acrylate 80% by mass, acrylic acid 19% by mass, hydroxyethyl acrylate 1% by mass And 0.22 part of 2,2′-azobisisobutylnitrile as a polymerization initiator are dissolved in 100% by mass of ethyl acetate, and after substitution with nitrogen, polymerization is carried out at 80 ° C. for 8 hours to obtain an acrylic ester having a weight average molecular weight of 700,000. A copolymer (6) was obtained.
＜アクリル共重合体（７）＞
　アクリル共重合体の調製攪拌機、寒流冷却器、温度計、滴下漏斗及び窒素ガス導入口を備えた反応容器に、アクリル酸２－メトキシエチル７５質量％、アクリル酸ｎ－ブチル１６質量％、メタクリル酸メチル８質量％、アクリル酸ヒドロキシエチル１質量％と重合開始剤として２，２’－アゾビスイソブチルニトリル０．２部とを酢酸エチル１００質量％に溶解し、窒素置換後、８０℃で８時間重合して重量平均分子量７０万のアクリル酸エステル共重合体（７）を得た。 <Acrylic copolymer (7)>
Preparation of acrylic copolymer In a reaction vessel equipped with a stirrer, cold flow cooler, thermometer, dropping funnel and nitrogen gas inlet, 2-methoxyethyl acrylate 75% by mass, n-butyl acrylate 16% by mass, methacrylic acid 8% by mass of methyl, 1% by mass of hydroxyethyl acrylate and 0.2 part of 2,2′-azobisisobutylnitrile as a polymerization initiator were dissolved in 100% by mass of ethyl acetate, and after nitrogen substitution, 8 hours at 80 ° C. Polymerization gave an acrylic ester copolymer (7) having a weight average molecular weight of 700,000.
＜アクリル共重合体（８）＞
　アクリル共重合体の調製攪拌機、寒流冷却器、温度計、滴下漏斗及び窒素ガス導入口を備えた反応容器に、アクリル酸２－メトキシエチル７５質量％、アクリル酸ｎ－ブチル２４質量、アクリル酸４－ヒドロキシブチル１質量％と重合開始剤として２，２’－アゾビスイソブチルニトリル０．２部とを酢酸エチル１００質量％に溶解し、窒素置換後、８０℃で８時間重合して重量平均分子量７０万のアクリル酸エステル共重合体（８）を得た。 <Acrylic copolymer (8)>
Preparation of acrylic copolymer In a reaction vessel equipped with a stirrer, cold flow cooler, thermometer, dropping funnel and nitrogen gas inlet, 75% by mass of 2-methoxyethyl acrylate, 24% by mass of n-butyl acrylate, 4% of acrylic acid -1% by weight of hydroxybutyl and 0.2 part of 2,2'-azobisisobutylnitrile as a polymerization initiator are dissolved in 100% by weight of ethyl acetate, and after nitrogen substitution, polymerized at 80 ° C for 8 hours to obtain a weight average molecular weight 700,000 acrylic ester copolymer (8) was obtained.
＜アクリル共重合体（９）＞
　アクリル酸ｎ－ブチルを２２質量％、アクリル酸ヒドロキシエチル３質量％とする以外は、アクリル酸エステル共重合体（１）と同様にして、重量平均分子量７０万のアクリル酸エステル共重合体（９）を得た。 <Acrylic copolymer (9)>
An acrylate ester copolymer having a weight average molecular weight of 700,000 (9) in the same manner as the acrylate ester copolymer (1) except that n-butyl acrylate is 22% by mass and hydroxyethyl acrylate is 3% by mass. )
＜アクリル共重合体（１０）＞
　アクリル共重合体の調製攪拌機、寒流冷却器、温度計、滴下漏斗及び窒素ガス導入口を備えた反応容器に、アクリル酸２－メトキシエチル４０質量％、アクリル酸ｎ－ブチル２４質量％、アクリル酸２エチルヘキシル３５質量％、アクリル酸ヒドロキシエチル１質量％と重合開始剤として２，２’－アゾビスイソブチルニトリル０．２部とを酢酸エチル１００質量％に溶解し、窒素置換後、８０℃で８時間重合して重量平均分子量７０万のアクリル酸エステル共重合体（１０）を得た。 <Acrylic copolymer (10)>
Preparation of acrylic copolymer In a reaction vessel equipped with a stirrer, cold flow cooler, thermometer, dropping funnel and nitrogen gas inlet, 2-methoxyethyl acrylate 40% by mass, n-butyl acrylate 24% by mass, acrylic acid Dissolve 35% by mass of 2-ethylhexyl, 1% by mass of hydroxyethyl acrylate, and 0.2 part of 2,2′-azobisisobutylnitrile as a polymerization initiator in 100% by mass of ethyl acetate. Polymerization with time was carried out to obtain an acrylate copolymer (10) having a weight average molecular weight of 700,000.
＜アクリル共重合体（１１）＞
　アクリル共重合体の調製攪拌機、寒流冷却器、温度計、滴下漏斗及び窒素ガス導入口を備えた反応容器に、アクリル酸２－メトキシエチル７０質量％、アクリル酸ｎ－ブチル２４質量％、アクリル酸ヒドロキシエチル１質量％、アクリル酸５質量％と重合開始剤として２，２’－アゾビスイソブチルニトリル０．２部とを酢酸エチル１００質量％に溶解し、窒素置換後、８０℃で８時間重合して重量平均分子量７０万のアクリル酸エステル共重合体（１１）を得た。 <Acrylic copolymer (11)>
Preparation of acrylic copolymer In a reaction vessel equipped with a stirrer, cold flow cooler, thermometer, dropping funnel and nitrogen gas inlet, 2-methoxyethyl acrylate 70% by mass, n-butyl acrylate 24% by mass, acrylic acid 1% by mass of hydroxyethyl, 5% by mass of acrylic acid and 0.2 part of 2,2′-azobisisobutylnitrile as a polymerization initiator are dissolved in 100% by mass of ethyl acetate, and after substitution with nitrogen, polymerization is carried out at 80 ° C. for 8 hours. As a result, an acrylic ester copolymer (11) having a weight average molecular weight of 700,000 was obtained.
＜粘着剤組成物（ａ）＞
　上記アクリル酸エステル共重合体（１）を酢酸エチルで希釈し、樹脂固形分３０質量％の粘着剤組成物（ａ）を得た。 <Adhesive composition (a)>
The acrylic ester copolymer (1) was diluted with ethyl acetate to obtain a pressure-sensitive adhesive composition (a) having a resin solid content of 30% by mass.
＜粘着剤組成物（ｂ）＞
　上記アクリル酸エステル共重合体（２）を酢酸エチルで希釈し樹脂固形分３０質量％の粘着剤組成物（ｂ）を得た。 <Adhesive composition (b)>
The acrylic ester copolymer (2) was diluted with ethyl acetate to obtain a pressure-sensitive adhesive composition (b) having a resin solid content of 30% by mass.
＜粘着剤組成物（ｃ）＞
　上記アクリル酸エステル共重合体（３）を酢酸エチルで希釈し樹脂固形分３０質量％の粘着剤組成物（ｃ）を得た。 <Adhesive composition (c)>
The acrylic ester copolymer (3) was diluted with ethyl acetate to obtain a pressure-sensitive adhesive composition (c) having a resin solid content of 30% by mass.
＜粘着剤組成物（ｄ）＞
　上記アクリル酸エステル共重合体（４）を酢酸エチルで希釈し樹脂固形分３０質量％の粘着剤（ｄ）を得た。 <Adhesive composition (d)>
The acrylic ester copolymer (4) was diluted with ethyl acetate to obtain a pressure-sensitive adhesive (d) having a resin solid content of 30% by mass.
＜粘着剤組成物（ｅ）＞
　上記アクリル酸エステル共重合体（５）を酢酸エチルで希釈し樹脂固形分３０質量％の粘着剤組成物（ｅ）を得た。 <Adhesive composition (e)>
The acrylic ester copolymer (5) was diluted with ethyl acetate to obtain a pressure-sensitive adhesive composition (e) having a resin solid content of 30% by mass.
＜粘着剤組成物（ｆ）＞
　上記アクリル酸エステル共重合体（６）を酢酸エチルで希釈し樹脂固形分３０質量％の粘着剤組成物（ｆ）を得た。 <Adhesive composition (f)>
The acrylic ester copolymer (6) was diluted with ethyl acetate to obtain a pressure-sensitive adhesive composition (f) having a resin solid content of 30% by mass.
＜粘着剤組成物（ｇ）＞
　上記アクリル酸エステル共重合体（７）を酢酸エチルで希釈し樹脂固形分３０質量％の粘着剤組成物（ｇ）を得た。 <Adhesive composition (g)>
The acrylic ester copolymer (7) was diluted with ethyl acetate to obtain a pressure-sensitive adhesive composition (g) having a resin solid content of 30% by mass.
＜粘着剤組成物（ｈ）＞
　上記アクリル酸エステル共重合体（８）を酢酸エチルで希釈し樹脂固形分３０質量％の粘着剤組成物（ｈ）を得た。 <Adhesive composition (h)>
The acrylic ester copolymer (8) was diluted with ethyl acetate to obtain a pressure-sensitive adhesive composition (h) having a resin solid content of 30% by mass.
＜粘着剤組成物（ｉ）＞
　上記アクリル酸エステル共重合体（９）を酢酸エチルで希釈し樹脂固形分３０質量％の粘着剤組成物（ｉ）を得た。 <Adhesive composition (i)>
The acrylic ester copolymer (9) was diluted with ethyl acetate to obtain a pressure-sensitive adhesive composition (i) having a resin solid content of 30% by mass.
＜粘着剤組成物（ｊ）＞
　上記アクリル酸エステル共重合体（１０）を酢酸エチルで希釈し樹脂固形分３０質量％の粘着剤組成物（ｊ）を得た。 <Adhesive composition (j)>
The acrylic ester copolymer (10) was diluted with ethyl acetate to obtain a pressure-sensitive adhesive composition (j) having a resin solid content of 30% by mass.
＜粘着剤組成物（ｋ）＞
　上記アクリル酸エステル共重合体（１１）を酢酸エチルで希釈し樹脂固形分３０質量％の粘着剤組成物（ｋ）を得た。 <Adhesive composition (k)>
The acrylic ester copolymer (11) was diluted with ethyl acetate to obtain a pressure-sensitive adhesive composition (k) having a resin solid content of 30% by mass.
（実施例１）
　上記粘着剤組成物（ａ）１００質量部にイソシアネート系架橋剤（日本ポリウレタン社製コロネートＨＸ、固形分７５％）を０．１質量部添加し１５分攪拌後、シリコーン化合物で片面を剥離処理した厚さ５０μｍのポリエステルフィルム（以下＃７５剥離フィルム）上に乾燥後の厚さが５０μｍになるように塗工して、７５℃で５分間乾燥した。得られた粘着シートと、シリコーン化合物で片面を剥離処理した厚さ３８μｍのポリエステルフィルム（以下＃３８剥離フィルム）を貼り合わせた。その後２３℃で７日間熟成し厚さ５０μｍの、ゲル分率５０％の基材レス粘着シートを得た。 Example 1
0.1 parts by mass of an isocyanate crosslinking agent (Nihon Polyurethane Coronate HX, solid content 75%) was added to 100 parts by mass of the pressure-sensitive adhesive composition (a), and the mixture was stirred for 15 minutes. It was coated on a 50 μm thick polyester film (hereinafter referred to as # 75 release film) so that the thickness after drying was 50 μm, and dried at 75 ° C. for 5 minutes. The obtained pressure-sensitive adhesive sheet and a 38 μm-thick polyester film (hereinafter referred to as # 38 release film) having one surface peel-treated with a silicone compound were bonded together. Thereafter, it was aged at 23 ° C. for 7 days to obtain a substrate-less pressure-sensitive adhesive sheet having a thickness of 50 μm and a gel fraction of 50%.
（実施例２）
　イソシアネート系架橋剤を０．０８質量部にする以外は、実施例１と同様にして、ゲル分率４０％の粘着シートを得た。 (Example 2)
A pressure-sensitive adhesive sheet having a gel fraction of 40% was obtained in the same manner as in Example 1 except that the isocyanate-based crosslinking agent was changed to 0.08 parts by mass.
（実施例３）
　粘着剤組成物（ａ）１００質量部を粘着剤組成物（ｂ）１００質量部にする以外は、実施例１と同様にして、ゲル分率５０％の粘着シートを得た。 (Example 3)
A pressure-sensitive adhesive sheet having a gel fraction of 50% was obtained in the same manner as in Example 1 except that 100 parts by weight of the pressure-sensitive adhesive composition (a) was changed to 100 parts by weight of the pressure-sensitive adhesive composition (b).
（実施例４）
　粘着剤組成物（ａ）１００質量部を粘着剤組成物（ｂ）１００質量部、イソシアネート系架橋剤を０．０８質量部にする以外は、実施例１と同様にして、ゲル分率４０％の粘着シートを得た。 (Example 4)
The gel fraction is 40% in the same manner as in Example 1 except that 100 parts by mass of the pressure-sensitive adhesive composition (a) is 100 parts by mass of the pressure-sensitive adhesive composition (b) and 0.08 parts by mass of the isocyanate-based crosslinking agent. An adhesive sheet was obtained.
（実施例５）
　粘着剤組成物（ａ）１００質量部を粘着剤組成物（ｇ）１００質量部にする以外は、実施例１と同様にして、ゲル分率５０％の粘着シートを得た。 (Example 5)
A pressure-sensitive adhesive sheet having a gel fraction of 50% was obtained in the same manner as in Example 1 except that 100 parts by weight of the pressure-sensitive adhesive composition (a) was changed to 100 parts by weight of the pressure-sensitive adhesive composition (g).
（実施例６）
　粘着剤組成物（ａ）１００質量部を粘着剤組成物（ｈ）１００質量部にする以外は、実施例１と同様にして、ゲル分率５０％の粘着シートを得た。 (Example 6)
A pressure-sensitive adhesive sheet having a gel fraction of 50% was obtained in the same manner as in Example 1 except that 100 parts by weight of the pressure-sensitive adhesive composition (a) was changed to 100 parts by weight of the pressure-sensitive adhesive composition (h).
（実施例７）
　粘着剤組成物（ａ）１００質量部を粘着剤組成物（ｉ）１００質量部にする以外は、実施例１と同様にして、ゲル分率５５％の粘着シートを得た。 (Example 7)
A pressure-sensitive adhesive sheet having a gel fraction of 55% was obtained in the same manner as in Example 1 except that 100 parts by weight of the pressure-sensitive adhesive composition (a) was changed to 100 parts by weight of the pressure-sensitive adhesive composition (i).
（比較例１）
　粘着剤組成物（ａ）１００質量部を粘着剤組成物（ｃ）１００質量部にする以外は、実施例１と同様にして、ゲル分率６０％の粘着シートを得た。 (Comparative Example 1)
A pressure-sensitive adhesive sheet having a gel fraction of 60% was obtained in the same manner as in Example 1 except that 100 parts by weight of the pressure-sensitive adhesive composition (a) was changed to 100 parts by weight of the pressure-sensitive adhesive composition (c).
（比較例２）
　粘着剤組成物（ａ）１００質量部を粘着剤組成物（ｄ）１００質量部にする以外は、実施例１と同様にして、ゲル分率６０％の粘着シートを得た。 (Comparative Example 2)
A pressure-sensitive adhesive sheet having a gel fraction of 60% was obtained in the same manner as in Example 1 except that 100 parts by weight of the pressure-sensitive adhesive composition (a) was changed to 100 parts by weight of the pressure-sensitive adhesive composition (d).
（比較例３）
　粘着剤組成物（ａ）１００質量部を粘着剤組成物（ｅ）１００質量部にする以外は、実施例１と同様にして、ゲル分率６０％の粘着シートを得た。 (Comparative Example 3)
A pressure-sensitive adhesive sheet having a gel fraction of 60% was obtained in the same manner as in Example 1 except that 100 parts by weight of the pressure-sensitive adhesive composition (a) was changed to 100 parts by weight of the pressure-sensitive adhesive composition (e).
（比較例４）
　上記粘着剤組成物（ｆ）１００質量部にイソシアネート系架橋剤（日本ポリウレタン社製コロネートＬ－４５、固形分４５％）を０．１質量部添加し１５分攪拌後、シリコーン化合物で片面を剥離処理した厚さ５０μｍのポリエステルフィルム（以下＃７５剥離フィルム）上に乾燥後の厚さが５０μｍになるように塗工して、７５℃で５分間乾燥した。得られた粘着シートと、シリコーン化合物で片面を剥離処理した厚さ３８μｍのポリエステルフィルム（以下＃３８剥離フィルム）を貼り合わせた。その後２３℃で７日間熟成し厚さ５０μｍの、ゲル分率７０％の基材レス粘着シートを得た。 (Comparative Example 4)
0.1 parts by mass of an isocyanate crosslinking agent (Nihon Polyurethane Coronate L-45, solid content 45%) was added to 100 parts by mass of the above-mentioned pressure-sensitive adhesive composition (f), and the mixture was stirred for 15 minutes. On the treated 50 μm thick polyester film (hereinafter referred to as # 75 release film), it was coated so that the thickness after drying was 50 μm, and dried at 75 ° C. for 5 minutes. The obtained pressure-sensitive adhesive sheet and a 38 μm-thick polyester film (hereinafter referred to as # 38 release film) having one surface peel-treated with a silicone compound were bonded together. Thereafter, it was aged at 23 ° C. for 7 days to obtain a substrate-less pressure-sensitive adhesive sheet having a thickness of 50 μm and a gel fraction of 70%.
（比較例５）
　粘着剤組成物（ａ）１００質量部を粘着剤組成物（ｊ）１００質量部、イソシアネート系架橋剤を０．３質量部にする以外は、実施例１と同様にして、ゲル分率８０％の粘着シートを得た。 (Comparative Example 5)
The gel fraction was 80% in the same manner as in Example 1 except that 100 parts by mass of the pressure-sensitive adhesive composition (a) was changed to 100 parts by mass of the pressure-sensitive adhesive composition (j) and 0.3 parts by mass of the isocyanate crosslinking agent. An adhesive sheet was obtained.
（比較例６）
　粘着剤組成物（ｆ）１００質量部を粘着剤組成物（ｋ）１００質量部、イソシアネート系架橋剤を０．１２質量部にする以外は、比較例４と同様にして、ゲル分率８０％の粘着シートを得た。 (Comparative Example 6)
The gel fraction is 80% in the same manner as in Comparative Example 4 except that 100 parts by weight of the pressure-sensitive adhesive composition (f) is changed to 100 parts by weight of the pressure-sensitive adhesive composition (k) and 0.12 parts by weight of the isocyanate-based crosslinking agent. An adhesive sheet was obtained.
　上記実施例及び比較例にて得られた粘着シートに関し、以下の評価を行った。得られた結果は表１～２に示した。 The following evaluation was performed on the pressure-sensitive adhesive sheets obtained in the above examples and comparative examples. The results obtained are shown in Tables 1-2.
（高温高湿条件下放置後の耐白濁性）
　粘着シートをポリエチレンテレフタレートフィルム、ガラスの順で貼り合わせて調整した試験サンプルを、６０℃９０％ＲＨ条件下に２５０時間放置し、試験サンプルを上記条件下から取り出した直後のヘイズを、（株）村上色彩技術研究所製「ＨＲ－１００型」を使用し、測定した。
　○：ヘイズ１．０％以下
　△：ヘイズ１．０％～３．０％
　×：ヘイズ３．０％以上 (White turbidity resistance after standing under high temperature and high humidity conditions)
A test sample prepared by laminating an adhesive sheet in the order of a polyethylene terephthalate film and glass was allowed to stand at 60 ° C. and 90% RH for 250 hours, and the haze immediately after taking the test sample out of the above conditions was Measurement was performed using “HR-100 Model” manufactured by Murakami Color Research Laboratory.
○: Haze 1.0% or less △: Haze 1.0% to 3.0%
X: Haze 3.0% or more
（酸化インジウムスズ膜の電気抵抗値測定）
　粘着シートの片面にポリエチレンテレフタレートフィルム（１００μｍ）に貼り合せた後、５０ｍｍ×５０ｍｍに裁断して、１００ｍｍ×１００ｍｍの酸化インジウムスズ蒸着ポリエチレンテレフタレートフィルムの酸化インジウムスズ膜面に貼り合わせを行う。貼り合せた粘着シートの両端に電気抵抗値測定機　三菱化学（株）製「ロレスターＧＰ」を使用し、初期の電気抵抗値（Ｒ１）を測定。粘着シートを貼り合わせた酸化インジウムスズ蒸着ポリエチレンテレフタレートフィルムを６０℃、９０％ＲＨ条件下に２５０時間放置し、２３℃、５０％ＲＨ条件下に１時間放置した後、初期と同じ箇所での電気抵抗値（Ｒ２）を測定した。酸化インジウムスズ（ＩＴＯ）膜の電気抵抗値変化率は下記の式で算出した。
　ＩＴＯ膜の電気抵抗値変化率（％）＝（（Ｒ２－Ｒ１）／Ｒ１）×１００
　　○：電気抵抗値変化率９０～１１０％
　　×：電気抵抗値変化率９０％未満もしくは１１０％以上 (Measurement of electrical resistance of indium tin oxide film)
After bonding to a polyethylene terephthalate film (100 μm) on one side of the pressure-sensitive adhesive sheet, it is cut into 50 mm × 50 mm and bonded to the indium tin oxide film surface of the 100 mm × 100 mm indium tin oxide-deposited polyethylene terephthalate film. The electrical resistance value measuring device “Lorestar GP” manufactured by Mitsubishi Chemical Corporation was used at both ends of the bonded adhesive sheet, and the initial electrical resistance value (R1) was measured. The indium tin oxide-deposited polyethylene terephthalate film with the adhesive sheet attached is left for 60 hours at 60 ° C. and 90% RH, left for 1 hour at 23 ° C. and 50% RH, The resistance value (R2) was measured. The electric resistance value change rate of the indium tin oxide (ITO) film was calculated by the following formula.
Change rate of electric resistance value of ITO film (%) = ((R2−R1) / R1) × 100
○: Electric resistance value change rate 90 to 110%
×: Electric resistance value change rate less than 90% or 110% or more
（印刷段差追従性評価１）
　作成した粘着シートの片側の剥離フィルムを剥がし、厚み１５μｍ、幅５ｍｍの印刷層が額縁状に装飾された厚み１００μｍ、長さ５０ｍｍ、幅４０ｍｍのポリエチレンテレフタレートフィルムに貼り合わせた。得られた試験片の残る片側の剥離フィルムを剥がし、厚み１ｍｍ、長さ５０ｍｍ、幅４０ｍｍガラス板に貼り合わせ、５気圧、７０℃、２０分の条件で加熱加圧処理を行った。加熱加圧処理後に２３℃下に１日放置し、印刷した装飾部近傍全体をマイクロスコープ（倍率３００倍）で観察し、気泡の混入等があるか確認した。気泡混入の評価基準は、以下の通りとした。
　○：直径５μｍ以上の気泡なし
　△：直径３０μｍ以上の気泡なし
　×：直径３０μｍ以上の気泡あり又は剥がれ (Printing level followability evaluation 1)
The release film on one side of the prepared pressure-sensitive adhesive sheet was peeled off, and bonded to a polyethylene terephthalate film having a thickness of 100 μm, a length of 50 mm, and a width of 40 mm in which a printing layer having a thickness of 15 μm and a width of 5 mm was decorated in a frame shape. The release film on one side where the obtained test piece remained was peeled off and bonded to a glass plate having a thickness of 1 mm, a length of 50 mm, and a width of 40 mm, and a heat and pressure treatment was performed under the conditions of 5 atm, 70 ° C., and 20 minutes. After the heat and pressure treatment, the sample was left at 23 ° C. for 1 day, and the entire printed decorative part was observed with a microscope (magnification 300 times) to confirm whether bubbles were mixed. The evaluation criteria for bubble contamination were as follows.
○: No bubbles with a diameter of 5 μm or more Δ: No bubbles with a diameter of 30 μm or more ×: Bubbles with a diameter of 30 μm or more or peeling
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000002
Figure JPOXMLDOC01-appb-T000002
　表中の配合の略記は、以下のとおりである。
　ＭＥＡ：アクリル酸メトキシエチル
　ＢＡ：アクリル酸ブチル
　２ＥＨＡ：アクリル酸２エチルへキシル
　ＨＥＡ：アクリル酸ヒドロキシエチル
　ＭＡ：メタクリル酸メチル
　ＡＡ：アクリル酸 Abbreviations for blending in the table are as follows.
MEA: methoxyethyl acrylate BA: butyl acrylate 2EHA: 2-ethylhexyl acrylate HEA: hydroxyethyl acrylate MA: methyl methacrylate AA: acrylic acid
　実施例１にて作成した粘着シートの片側の剥離フィルムを剥がし、ポリエチレンテレフタレートフィルムの一面にハードコート層が設けられたハードコートフィルムのハードコートを有さない面に粘着シートを貼り合わせ、ハードコート層を有する基材の片面に粘着剤層を有する飛散防止粘着シートを得た。得られた飛散防止粘着シートに関し、以下の評価を行った。得られた結果は表３に示した。 The release film on one side of the pressure-sensitive adhesive sheet prepared in Example 1 is peeled off, and the pressure-sensitive adhesive sheet is bonded to the surface having no hard coat of the hard coat film provided with a hard coat layer on one surface of the polyethylene terephthalate film. The scattering prevention adhesive sheet which has an adhesive layer on the single side | surface of the base material which has a layer was obtained. The following evaluation was performed about the obtained scattering prevention adhesive sheet. The results obtained are shown in Table 3.
（印刷段差追従性評価２）
　得られた粘着シートの残る片側の剥離フィルムを剥がし、印刷層が額縁状に装飾された厚み１ｍｍ、長さ５０ｍｍ、幅４０ｍｍガラス板に貼り合わせ、５気圧、７０℃、２０分の条件で加熱加圧処理を行った。加熱加圧処理直後に、印刷した装飾部近傍全体をマイクロスコープ（倍率３００倍）で観察し、気泡の混入等があるか確認した。気泡混入の評価基準は、以下の通りとした。
　○：直径５μｍ以上の気泡なし
　△：直径３０μｍ以上の気泡なし
　×：直径３０μｍ以上の気泡あり又は剥がれ (Printing step follow-up evaluation 2)
The release film on one side of the obtained pressure-sensitive adhesive sheet is peeled off, and the printed layer is bonded to a glass plate decorated in a frame shape with a thickness of 1 mm, a length of 50 mm, and a width of 40 mm. A pressure treatment was performed. Immediately after the heating and pressurizing treatment, the entire printed decorative part was observed with a microscope (magnification 300 times), and it was confirmed whether bubbles were mixed. The evaluation criteria for bubble contamination were as follows.
○: No bubbles with a diameter of 5 μm or more Δ: No bubbles with a diameter of 30 μm or more ×: Bubbles with a diameter of 30 μm or more or peeling
Figure JPOXMLDOC01-appb-T000003
Figure JPOXMLDOC01-appb-T000003
　上記表のとおり、実施例１～７の粘着シートは、カルボキシル基含有単量体が無くても、高温高湿条件下でヘイズは上昇せず、白濁しないことが確認された。また、実施例１～４の粘着シートは印刷段差への追従も優れており、ハードコート層が設けられたハードコートフィルムを基材とする場合にも良好な印刷段差追従性を有するものであった。一方、親水性の高いアクリル酸メトキシエチルを使用しているが、炭素数８のアクリル酸２エチルへキシルを用いた比較例１、炭素数４のアクリル酸ｎ－ブチルの含有量が４９質量％の比較例２、親水性の高いアクリル酸アルコキシアルキル単量体を含有しない比較例３及びアクリル酸アルコキシアルキル単量体の含有量が低い比較例５では、高温高湿条件下でヘイズが上昇し、白濁が確認された。また、カルボキシル基含有単量体であるアクリル酸を有する比較例４及び比較例６の粘着シートでは、高温高湿条件下で白濁しないが、ＩＴＯの電気抵抗値の上昇が確認された。 As shown in the above table, it was confirmed that the adhesive sheets of Examples 1 to 7 did not increase in haze and did not become cloudy under high temperature and high humidity conditions even without a carboxyl group-containing monomer. In addition, the pressure-sensitive adhesive sheets of Examples 1 to 4 are excellent in following a printing step, and have a good printing step following property even when a hard coat film provided with a hard coat layer is used as a base material. It was. On the other hand, although methoxyethyl acrylate having high hydrophilicity is used, Comparative Example 1 using 2-ethylhexyl acrylate having 8 carbon atoms, the content of n-butyl acrylate having 4 carbon atoms is 49% by mass In Comparative Example 2 of Comparative Example 3, Comparative Example 3 not containing a highly hydrophilic alkoxyalkyl acrylate monomer, and Comparative Example 5 having a low content of alkoxyalkyl acrylate monomer, haze increased under high temperature and high humidity conditions. The cloudiness was confirmed. Moreover, in the adhesive sheet of the comparative example 4 and the comparative example 6 which has acrylic acid which is a carboxyl group-containing monomer, although it did not become cloudy on high temperature, high humidity conditions, the raise of the electrical resistance value of ITO was confirmed.
　１，１’，１１，２１，２１’　金属面貼付用粘着シート
　２，１２，２２　表面保護パネル
　３，１３，２３　印刷段差
　４，４’　ＩＴＯフィルム
　４ａ，４ａ’　透明樹脂フィルム
　４ｂ，４ｂ’　ＩＴＯ
　５，１７，２７　筐体
　６，１８，２８　画像表示モジュール
　７，１９，２９　接着部材
　１４　ＩＴＯ
　１５，２５　粘着剤層
　１６，２６　ハードコートフィルム
　２４　ＩＴＯガラス
　２５ａ　透明ガラス
　２５ｂ，２５ｃ　ＩＴＯ 1,1 ′, 11,21,21 ′ Adhesive sheet for metal surface sticking 2,12,22 Surface protection panel 3,13,23 Printing level difference 4,4 ′ ITO film 4a, 4a ′ Transparent resin film 4b, 4b ′ ITO
5, 17, 27 Case 6, 18, 28 Image display module 7, 19, 29 Adhesive member 14 ITO
15, 25 Adhesive layer 16, 26 Hard coat film 24 ITO glass 25a Transparent glass 25b, 25c ITO

Claims (4)

  1. 　金属面に貼り合わせる粘着シートであって、
    　前記粘着シートが、（メタ）アクリル酸エステル共重合体を使用したアクリル系粘着剤からなる粘着剤層を有し、
    　前記（メタ）アクリル酸エステル共重合体が、（メタ）アクリル酸アルコキシアルキルエステル単量体（Ａ）及び炭素数が１～４のアクリル基を有する（メタ）アクリル酸アルキルエステル（Ｂ）を単量体成分として含有し、
    　（メタ）アクリル酸エステル共重合体を構成する単量体成分中の前記（メタ）アクリル酸アルコキシアルキルエステル単量体（Ａ）の含有量が５０質量％以上、前記炭素原子数が１～４のアクリル基を有する（メタ）アクリル酸アルキルエステル（Ｂ）の含有量が５～４５質量％であり、
    　（メタ）アクリル酸エステル共重合体を構成する単量体成分中のカルボキシル基含有単量体の含有量が１％以下であることを特徴とする金属面貼付用粘着シート。     An adhesive sheet to be bonded to a metal surface,
    The pressure-sensitive adhesive sheet has a pressure-sensitive adhesive layer made of an acrylic pressure-sensitive adhesive using a (meth) acrylic acid ester copolymer,
    The (meth) acrylic acid ester copolymer comprises a (meth) acrylic acid alkoxyalkyl ester monomer (A) and a (meth) acrylic acid alkyl ester (B) having an acrylic group having 1 to 4 carbon atoms. Contained as a mass component,
    The content of the (meth) acrylic acid alkoxyalkyl ester monomer (A) in the monomer component constituting the (meth) acrylic acid ester copolymer is 50% by mass or more, and the number of carbon atoms is 1-4. The content of the (meth) acrylic acid alkyl ester (B) having an acrylic group of 5 to 45% by mass,
    A pressure-sensitive adhesive sheet for sticking a metal surface, wherein the content of a carboxyl group-containing monomer in a monomer component constituting a (meth) acrylic acid ester copolymer is 1% or less.
  2. 　前記炭素原子数が１～４のアクリル基を有する（メタ）アクリル酸アルキルエステル（Ｂ）が、アクリル酸ｎ－ブチルである請求項１に記載の金属面貼付用粘着シート。 The pressure-sensitive adhesive sheet for metal surface sticking according to claim 1, wherein the (meth) acrylic acid alkyl ester (B) having an acrylic group having 1 to 4 carbon atoms is n-butyl acrylate.
  3. 　前記（メタ）アクリル酸エステル共重合体の重量平均分子量が、３０万～１６０万である請求項１又は２に記載の金属面貼付用粘着シート。 The pressure-sensitive adhesive sheet for sticking a metal surface according to claim 1 or 2, wherein the (meth) acrylic acid ester copolymer has a weight average molecular weight of 300,000 to 1,600,000.
  4. 　前記粘着剤層のゲル分率が３０～８０質量％である請求項１～３のいずれかに記載の金属面貼付用粘着シート。 The pressure-sensitive adhesive sheet for metal surface sticking according to any one of claims 1 to 3, wherein the pressure-sensitive adhesive layer has a gel fraction of 30 to 80% by mass.
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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013142124A (en) * 2012-01-11 2013-07-22 Soken Chem & Eng Co Ltd Adhesive tape for conductive film and laminate for touch panel
JP2013253160A (en) * 2012-06-06 2013-12-19 Soken Chem & Eng Co Ltd Pressure-sensitive adhesive sheet for conductive film, laminate, and touch panel having the laminate
JP2015193702A (en) * 2014-03-31 2015-11-05 リンテック株式会社 Method for producing surface protective film for transparent conductive substrate, surface protective film for transparent conductive substrate, and laminate
JP2016084438A (en) * 2014-10-28 2016-05-19 Dic株式会社 Adhesive film, information display device and portable electronic terminal
WO2019203004A1 (en) * 2018-04-18 2019-10-24 Dic株式会社 Adhesive tape and article

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6452483B2 (en) * 2015-02-16 2019-01-16 日東電工株式会社 Optical film with adhesive and image display device
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KR20220003033U (en) 2021-06-18 2022-12-28 임환석 Tatoo sticker

Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0584925A (en) * 1991-09-26 1993-04-06 Canon Inc Adhesive tape and recording head
JPH07102230A (en) * 1993-09-30 1995-04-18 Nippon Synthetic Chem Ind Co Ltd:The Pressure-sensitive adhesive composition
JPH10226776A (en) * 1997-02-14 1998-08-25 Lintec Corp Pressure-sensitive adhesive composition and method for utilizing the same
JPH11140411A (en) * 1997-11-13 1999-05-25 Mitsubishi Rayon Co Ltd Ultraviolet-curable tack agent composition
JP2001123136A (en) * 1999-10-28 2001-05-08 Soken Chem & Eng Co Ltd Moisture-resistant adhesive sheet and its use
WO2009060909A1 (en) * 2007-11-07 2009-05-14 The Nippon Synthetic Chemical Industry Co., Ltd. Pressure-sensitive adhesive, pressure-sensitive adhesive for optical member, optical member, and perssure-sensitive adhesive for temporary surface protection
WO2010018795A1 (en) * 2008-08-11 2010-02-18 住友化学株式会社 Optical film with adhesive and optical laminate using same
JP2010066755A (en) * 2008-08-11 2010-03-25 Sumitomo Chemical Co Ltd Optical film with adhesive and optical laminate using it
JP2010241864A (en) * 2009-04-01 2010-10-28 Nitto Denko Corp Double-coated pressure-sensitive adhesive sheet, process for producing the same, pressure-sensitive adhesive type optically functional film and pressure-sensitive adhesive type hard coat film
WO2010147047A1 (en) * 2009-06-18 2010-12-23 日東電工株式会社 Optical adhesive sheet
JP2011153169A (en) * 2010-01-26 2011-08-11 Daio Paper Corp Self-adhesive sheet
WO2012093607A1 (en) * 2011-01-06 2012-07-12 綜研化学株式会社 Adhesive and pressure-sensitive adhesive sheet

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11123136A (en) * 1997-10-21 1999-05-11 Ishino Seisakusho:Kk Eating and drinking contents-displaying system
JP5483808B2 (en) * 2007-08-14 2014-05-07 チェイル インダストリーズ インコーポレイテッド Adhesive composition and optical member
WO2009031421A1 (en) * 2007-09-07 2009-03-12 Dic Corporation Double-sided adhesive tape
CN101586006A (en) * 2008-05-23 2009-11-25 日东电工株式会社 Pressure-sensitive adhesive composition, pressure-sensitive adhesive sheet, and method for producing the same
CN101705067B (en) * 2009-11-23 2012-01-18 南亚塑胶工业股份有限公司 Adhesive agent composition for attaching to polarizing plate

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0584925A (en) * 1991-09-26 1993-04-06 Canon Inc Adhesive tape and recording head
JPH07102230A (en) * 1993-09-30 1995-04-18 Nippon Synthetic Chem Ind Co Ltd:The Pressure-sensitive adhesive composition
JPH10226776A (en) * 1997-02-14 1998-08-25 Lintec Corp Pressure-sensitive adhesive composition and method for utilizing the same
JPH11140411A (en) * 1997-11-13 1999-05-25 Mitsubishi Rayon Co Ltd Ultraviolet-curable tack agent composition
JP2001123136A (en) * 1999-10-28 2001-05-08 Soken Chem & Eng Co Ltd Moisture-resistant adhesive sheet and its use
WO2009060909A1 (en) * 2007-11-07 2009-05-14 The Nippon Synthetic Chemical Industry Co., Ltd. Pressure-sensitive adhesive, pressure-sensitive adhesive for optical member, optical member, and perssure-sensitive adhesive for temporary surface protection
WO2010018795A1 (en) * 2008-08-11 2010-02-18 住友化学株式会社 Optical film with adhesive and optical laminate using same
JP2010066755A (en) * 2008-08-11 2010-03-25 Sumitomo Chemical Co Ltd Optical film with adhesive and optical laminate using it
JP2010241864A (en) * 2009-04-01 2010-10-28 Nitto Denko Corp Double-coated pressure-sensitive adhesive sheet, process for producing the same, pressure-sensitive adhesive type optically functional film and pressure-sensitive adhesive type hard coat film
WO2010147047A1 (en) * 2009-06-18 2010-12-23 日東電工株式会社 Optical adhesive sheet
JP2011153169A (en) * 2010-01-26 2011-08-11 Daio Paper Corp Self-adhesive sheet
WO2012093607A1 (en) * 2011-01-06 2012-07-12 綜研化学株式会社 Adhesive and pressure-sensitive adhesive sheet

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013142124A (en) * 2012-01-11 2013-07-22 Soken Chem & Eng Co Ltd Adhesive tape for conductive film and laminate for touch panel
JP2013253160A (en) * 2012-06-06 2013-12-19 Soken Chem & Eng Co Ltd Pressure-sensitive adhesive sheet for conductive film, laminate, and touch panel having the laminate
JP2015193702A (en) * 2014-03-31 2015-11-05 リンテック株式会社 Method for producing surface protective film for transparent conductive substrate, surface protective film for transparent conductive substrate, and laminate
JP2016084438A (en) * 2014-10-28 2016-05-19 Dic株式会社 Adhesive film, information display device and portable electronic terminal
WO2019203004A1 (en) * 2018-04-18 2019-10-24 Dic株式会社 Adhesive tape and article
JPWO2019203004A1 (en) * 2018-04-18 2020-05-28 Dic株式会社 Adhesive tapes and articles
US12012529B2 (en) 2018-04-18 2024-06-18 Dic Corporation Adhesive tape and article

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