TW201631087A - Adhesive sheet and optical element - Google Patents

Abstract

The present invention provides an adhesive sheet that can realize increased antistatic characteristics and enhance the pickup property, and optical element protected by the above-described adhesive sheet. The invented adhesive sheet has its characteristics by that: sequentially composed of first resin layer, bonding layer, second resin layer and adhesive layer formed by the adhesive composition, wherein, the thickness of the bonding layer relative to summation of those of the above-described first resin layer and the second resin layer has a ratio below 0.50, and the bonding layer stored at 23 DEG C has the modulus of elasticity between 1.0×10<SP>4</SP> Pa and 5.0×10<SP>7</SP>Pa. The first resin layer and the opposite side of said surface containing the adhesive layer have a coating layer, the above-described coating layer is formed by the coating composition that contains polyaniline sulfonic acid as a conductive polymer, polyester resin as a binder, and isocyanate compound as a crosslinking agent.

Description

Adhesive sheet and optical member

The present invention relates to an adhesive sheet and an optical member.

The adhesive sheet of the present invention is used as a polarizing plate, a wave plate, a phase difference plate, an optical compensation film, a reflective sheet, and a brightness enhancement film used for protecting a liquid crystal display, an organic EL (electroluminescence) display, a touch panel display, or the like. A surface protective film used for the purpose of covering the surface of an optical member such as a glass, a cover sheet, a hard coat film, a transparent conductive glass, or a transparent conductive film is useful.

In recent years, when optical parts and electronic parts are transported or mounted on a printing substrate, each part is transferred by a state in which a specific sheet is wrapped or a state in which an adhesive tape is attached. Among them, a surface protective film is particularly widely used in the field of optical and electronic parts.

The surface protective film is generally applied to the object to be bonded via an adhesive applied to the side of the support film, and is used for the purpose of preventing scratches or stains generated during processing and transportation of the substrate (Patent Document 1). For example, a panel of a liquid crystal display is formed by bonding an optical member such as a polarizing plate or a wave plate to a liquid crystal cell via an adhesive. These optical members are bonded to the surface protective film via an adhesive to prevent scratches or stains generated during processing and transportation of the adherend.

Then, the optical member is bonded to the liquid crystal cell or the like, and then the protective film is peeled off at a stage where the protective film is no longer needed. In general, the protective film or the optical member is made of a plastic material, and thus has high electrical insulation and generates static electricity upon rubbing or peeling. because Therefore, static electricity is also generated when the protective film is peeled off from an optical member such as a polarizing plate. When a voltage is applied to the liquid crystal in a state where static electricity remains, the alignment of the liquid crystal molecules may be lost or a defect of the panel may occur. In addition, the presence of static electricity may also cause dust adsorption or workability. In view of the above, an antistatic treatment is performed on the surface protective film, for example, by forming an antistatic layer or applying an antistatic coating layer as a surface layer (top coat layer, back layer) of the surface protective film to impart an antistatic function. (Refer to Patent Documents 2 and 3).

Further, in recent years, as a conductive polymer for imparting an antistatic function to the surface layer of the surface protective film, PEDOT (poly(3,4-ethylenedioxythiophene))/PSS (polystyrenesulfonic acid) is used. Salt) (polythiophene type) is a water-dispersible type. However, when the antistatic layer is formed using the above conductive polymer, PSS (corresponding to a dopant) is detached from PEDOT over time to cause an increase in surface resistivity or peeling electrostatic voltage, and the like, and oxidative degradation occurs. Or the rise of the surface resistivity (deterioration) associated with photodegradation.

In addition, when the surface resistivity or the like is increased (deteriorated), static electricity is generated when the surface protective film is peeled off from the adherend, and there is a concern that a problem occurs.

Further, the surface protective film is peeled off at a stage where it is no longer necessary. However, as the liquid crystal display panel is enlarged or thinned, damage to the polarizing plate or the liquid crystal cell is likely to occur in the peeling step, and therefore it is required to have peeling off. When the adhesion is moderate, such as lifting, and light peelability, pick-up property, and the like are required to be peeled off. In particular, in recent years, as the thickness of the display is reduced, the optical member constituting the display is also thinned, and the optical member having a thickness of 150 μm or less and a thickness of 100 μm or less is deflected by the optical member during the transport step, thereby making it impossible to transport. In addition, there is also a problem that the optical member cannot be completely bonded to other members. In order to avoid such problems, the surface protective film is suppressed from being thickened by the thickening of the surface protective film, but the peeling becomes heavy due to the thickening. Therefore, when the surface protective film is peeled off by the pickup tape at the stage where the surface protective film is no longer required, it becomes Unable to pick up the bad condition. Therefore, an adhesive sheet capable of suppressing deflection and achieving light peelability and pick-up property to be re-peelable is required.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2003-334911

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2000-26817

[Patent Document 3] Japanese Patent Laid-Open Publication No. 2008-255332

Therefore, the present invention has been extensively studied in view of the above-described matters, and as a result, an adhesive sheet capable of improving the antistatic property and the pickup property and an optical member protected by the above-mentioned adhesive sheet are provided.

That is, the adhesive sheet of the present invention is characterized in that it has a first resin layer, an adhesive layer, a second resin layer, and an adhesive layer formed of an adhesive composition, the thickness of the above-mentioned adhesive layer being relative to the first resin The ratio of the thickness of the layer to the sum of the thicknesses of the second resin layers is 0.50 or less, and the storage elastic modulus at 23 ° C of the subsequent layer is 1.0 × 10 ⁴ Pa or more and less than 5.0 × 10 ⁷ Pa. a surface of the resin layer opposite to the surface having the adhesive layer, wherein the top coat layer comprises a polyaniline sulfonic acid as a conductive polymer component, a polyester resin as a binder component, and A composition for topcoat of an isocyanate compound of a crosslinking agent is formed.

In the adhesive sheet of the present invention, it is preferred that the top coat composition further contains a fatty guanamine as a lubricant.

In the adhesive sheet of the present invention, it is preferred that at least one of the resin layers is a polyester film.

In the adhesive sheet of the present invention, it is preferable that the adhesive composition contains at least one selected from the group consisting of an acrylic adhesive, an urethane-based adhesive, and a polyester-based adhesive.

In the adhesive sheet of the present invention, it is preferred that the above adhesive composition contains an antistatic agent. Minute.

The optical member of the present invention is preferably protected by the above-mentioned adhesive sheet.

The adhesive sheet according to the present invention has a resin layer film in which a resin layer is laminated via an adhesive layer (a first resin layer, an adhesive layer, and a second resin layer are sometimes referred to as a laminated film), whereby The deformation at the time of peeling of the adhesive sheet achieves stress relaxation in a portion of the adhesive layer, and can be picked up at a peeling force (adhesion force) lower than that of the resin layer alone. Further, according to the laminated structure described above, the amount of deflection of the laminated film can be improved as compared with the amount of deflection of each resin layer film (the amount of deflection is reduced), and the problem of poor conveyance due to breakage or deformation in the conveyance step can be improved. An increase in manufacturing efficiency can be achieved. Further, it is preferable that the surface of the resin layer film has a top coat layer containing a specific raw material, and an adhesive sheet having excellent antistatic properties or pick-up property can be obtained.

1‧‧‧Adhesive sheet (surface protective film)

1A‧‧‧Surface coated surface

2‧‧‧Polar plate

3‧‧‧Acrylic resin board

4‧‧‧ fixed table

5‧‧‧potentiometer

6‧‧‧First resin layer

7‧‧‧Next layer

8‧‧‧Second resin layer

12‧‧‧Resin film (first resin layer + adhesive layer + second resin layer)

14‧‧‧Face coating

20‧‧‧Adhesive layer

20A‧‧‧Adhesive

50‧‧‧Flat polarizer

60‧‧‧Single-sided adhesive tape

62‧‧‧Adhesive layer (adhesive surface)

64‧‧‧Substrate

130‧‧‧Double adhesive tape

132‧‧‧Stainless steel plate

160‧‧‧Single-sided adhesive tape

162‧‧‧Acrylic adhesive (adhesive layer)

162A‧‧‧ adhesive surface

164‧‧‧ resin film (first resin layer + adhesive layer + second resin layer)

G‧‧‧glass plate

H‧‧‧ Height from the center

L‧‧‧ load

T‧‧‧No.31B tape

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic cross-sectional view showing a protective film according to a preferred embodiment of the present invention.

Fig. 2 is an explanatory view for explaining a method of measuring a peeling electrostatic voltage.

Fig. 3 is an explanatory view for explaining a method of measuring the back adhesion (A).

Fig. 4 is an explanatory view showing a method of peeling off an adhesive sheet of an embodiment.

Fig. 5 is an explanatory view for explaining a method of measuring the amount of deflection.

Hereinafter, embodiments of the present invention will be described in detail.

<Adhesive sheet (surface protective film)>

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic cross-sectional view showing an adhesive sheet of a preferred embodiment of the present invention. The adhesive sheet 1 has the first resin layer 6, the subsequent layer 7, and the second resin layer 8 in this order (the composition of the first resin layer, the subsequent layer, and the second resin layer may be referred to as "resin layer" in some cases. The film "" and the adhesive layer 20 have a top coat layer 14 on the surface of the first resin layer 6 opposite to the surface having the above-mentioned adhesive layer 20. The adhesive sheet 1 is the same via the adhesive layer 7 The first resin layer 6 and the second resin layer 8 are laminated, and have a laminate of the adhesive layer 20 and the top coat layer 14. Further, the adhesive layer 20 is bonded to a member to be bonded (for example, an optical member). Further, although not shown, it is preferable to adhere a spacer to the surface of the adhesive layer 20 before bonding to the adherend.

<Resin layer>

The resin layer is preferably composed of a resin film. The thickness of the resin layer is preferably from 1 μm to 200 μm, more preferably from 12 μm to 75 μm. The relationship between the thickness of the first resin layer and the thickness of the second resin layer is preferably (the thickness of the first resin layer) (Thickness of the second resin layer), the thickness of the first resin layer is preferably from 1 μm to 50 μm, more preferably from 4 μm to 38 μm, most preferably from 10 μm to 25 μm. Further, the thickness of the second resin layer is preferably from 10 μm to 200 μm, more preferably from 25 μm to 130 μm, most preferably from 38 μm to 75 μm. In the above range, it is preferable to achieve both the amount of deflection of the adhesive sheet and the pick-up property.

The tensile strength in the MD direction (flow direction) of at least one of the resin layers can be set to any appropriate value. The tensile strength in the MD direction (flow direction) of the resin layer is preferably from 90 MPa to 350 MPa, further preferably from 110 MPa to 320 MPa, more preferably from 130 MPa to 300 MPa, and most preferably from 180 MPa to 250 MPa. If it is in the above range, the amount of deflection of the adhesive sheet can be suppressed, which is a preferable aspect.

In the technique disclosed herein, the resin material constituting the resin layer (support, substrate) can be used without particular limitation. For example, transparency, mechanical strength, thermal stability, moisture barrier property, and isotropy are preferably used. Excellent in flexibility, dimensional stability, etc. In particular, since the resin layer has flexibility, it can be applied by applying a pressure-sensitive adhesive composition by a roll coater or the like, and can be wound into a roll shape.

As the resin layer, for example, a polyester-based polymer such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), or polybutylene terephthalate can be preferably used; a cellulose-based polymer such as diacetyl cellulose or triacetyl cellulose; a polycarbonate polymer; an acrylic polymer such as polymethyl methacrylate or the like as a main resin component (tree) A plastic film made of a resin material of a main component of the fat component, which is typically a component of 50% by mass or more, is used as the resin layer. Other examples of the resin material include styrene polymers such as polystyrene and acrylonitrile-styrene copolymer; polyethylene, polypropylene, polyolefin having a cyclic structure or a norbornene structure, and ethylene- An olefin-based polymer such as a propylene copolymer; a vinyl chloride-based polymer; a phthalamide-based polymer such as nylon 6, nylon 6,6 or an aromatic polyamine as a resin material. Another example of the above-mentioned resin material includes a quinone imine polymer, a fluorene polymer, a polyether fluorene polymer, a polyether ether ketone polymer, a polyphenylene sulfide polymer, and a vinyl alcohol polymer. A vinylidene chloride-based polymer, a vinyl butyral-based polymer, an aryl ester-based polymer, a polyoxymethylene-based polymer, or an epoxy-based polymer. It may also be a resin layer containing a blend of two or more of the above polymers.

Further, as the resin layer, a plastic film containing a transparent thermoplastic resin material is preferable, and among the plastic films, at least one of the resin layers in the adhesive sheet of the present invention is a polyester film. kind. Here, the polyester film refers to a main skeleton having an ester bond as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate or the like. The polymer material (polyester resin) is the main resin component. The polyester film has excellent properties as a resin layer of an adhesive sheet (surface protective film), and is excellent in optical characteristics or dimensional stability, and has a property of being easily charged. Moreover, as a resin layer satisfying the said tensile strength, the following resin is mentioned. A polyester-based polymer such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), or polybutylene terephthalate; diethyl phthalocyanine, a cellulose-based polymer such as triacetonitrile cellulose; a polycarbonate-based polymer; an acrylic polymer such as polymethyl methacrylate; a polystyrene-based polymer; and a polyolefin having a cyclic structure or a norbornene structure. a resin material such as nylon 6, nylon 6,6 or a phthalamide-based polymer such as an aromatic polyamine, which is a main resin component (a main component of a resin component, typically a component of 50% by mass or more) A plastic film is used as the above resin layer. It may also be a resin layer containing a blend of two or more of the above polymers.

In the resin material constituting the resin layer, various additives such as an antioxidant, an ultraviolet absorber, a plasticizer, and a colorant (pigment, dye, etc.) may be blended as needed. Further, a known or conventional surface treatment such as a corona discharge treatment, a plasma treatment, an ultraviolet irradiation treatment, an acid treatment, an alkali treatment, or a primer coating can be applied to the surface of the resin layer. Such a surface treatment can be, for example, a treatment for improving the adhesion of the resin layer to the adhesive layer or the top coat layer (the anchoring property of the adhesive layer, etc.). It is preferable to use a surface treatment in which a polar group such as a hydroxyl group is introduced onto the surface of the resin layer.

Further, the constitution (for example, thickness, forming material, modulus of elasticity, tensile elongation, and the like) of the first resin layer and the second resin layer may be the same or different, and may be appropriately selected.

<Next layer>

The "adhesive layer" in the present invention means that the surface of the adjacent resin layer is bonded to the surface, and is integrated with practically sufficient adhesion and subsequent time. Examples of the material for forming the adhesive layer include an adhesive, an adhesive, and a tackifier. The subsequent layer may be a multi-layered construction in which a tackifying coating is formed on the surface of the resin layer and an adhesive layer is formed thereon. Further, the "adhesive layer" in the present invention means a peelable (repeelable) one.

The ratio of the thickness of the layer to the sum of the thickness of the first resin layer and the thickness of the second resin layer is 0.50 or less, preferably 0.40 or less, more preferably 0.35 or less, and most preferably 0.30 or less. By setting it in such a range, the warpage of a to-be-attached body (for example, an optical member) can be suppressed extremely well. On the other hand, the ratio of the above thicknesses is preferably 0.03 or more. By setting it within such a range, the obtained adhesive sheet is more excellent in the bendability, and the extremely excellent peeling property can be implement|achieved.

The thickness of the layer is then preferably thinner than the thickness of the resin layer. The difference between the thickness of the resin layer and the thickness of the adhesive layer is preferably 2 μm or more, and more preferably 5 μm or more. If the difference is too small, depending on the thickness of the resin layer, the pick-up property of the adhesive sheet may be insufficient. The thickness of the layer is preferably from 1 μm to 50 μm, more preferably from 2 μm to 25 μm, still more preferably from 5 μm to 20 μm. If the thickness of the adhesive layer is too thick, there is a problem in the formation of the adhesive layer (for example) Such as paste defect).

According to the adhesive sheet of the present invention, stress relaxation can be achieved by providing an adhesive layer, and the peeling force of the obtained adhesive sheet can be lowered, the pick-up property can be improved, and pick-up can be performed lower than the peeling force of the individual resin layers. In addition, the resin layer film (the order of the first resin layer, the adhesive layer, and the second resin layer) obtained by laminating the resin layer through the above-mentioned adhesive layer can make the amount of deflection of the laminated film and the respective resin layer films. The improvement in the amount of deflection (reduction in the amount of deflection) improves the problem of poor conveyance caused by breakage or deformation in the conveyance step, and the improvement in manufacturing efficiency can be achieved. Further, the storage elastic modulus at 23 ° C of the subsequent layer is 1.0 × 10 ⁴ Pa or more and less than 5.0 × 10 ⁷ Pa, preferably 1.0 × 10 ⁴ Pa or more and less than 1.0 × 10 ⁷ Pa, more preferably It is 1.0 × 10 ⁵ Pa or more and less than 1.0 × 10 ⁶ Pa. The storage elastic modulus of the above-mentioned adhesive layer can be measured using a dynamic viscoelasticity measuring device at a frequency of 1 Hz.

The layer is then representatively formed from an adhesive. As the adhesive, an acrylic adhesive is preferably used. The acrylic adhesive preferably contains a (meth)acrylic polymer and a crosslinking agent. The crosslinking agent is not particularly limited as long as it is a compound which reacts with the (meth)acrylic polymer, and it is preferred to use an isocyanate compound, an epoxy compound, a melamine resin, an aziridine derivative, and a metal chelate. Compound.

The (meth)acrylic polymer refers to a polymer or copolymer synthesized from an acrylic monomer and/or a methacrylic monomer (referred to as "(meth)acrylate" in the present specification). When the (meth)acrylic polymer is a copolymer, the arrangement state of the molecules is not particularly limited, and may be a random copolymer, a block copolymer, or a graft copolymer. Preferred molecular alignment states are random copolymers. Further, the polymerization method is not particularly limited, and polymerization can be carried out by a known method such as solution polymerization, emulsion polymerization, bulk polymerization or suspension polymerization.

The above (meth)acrylic polymer can be obtained, for example, by homopolymerizing or copolymerizing an alkyl (meth)acrylate. The alkyl group of the alkyl (meth)acrylate may be linear, branched or cyclic. The alkyl group of the alkyl (meth) acrylate preferably has a carbon number of from 1 to 18, more preferably 1 ~10.

Specific examples of the alkyl (meth)acrylate include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, and n-butyl (meth)acrylate. Isobutyl (meth)acrylate, tert-butyl (meth)acrylate, n-amyl (meth)acrylate, isoamyl (meth)acrylate, n-hexyl (meth)acrylate, (meth)acrylic acid Isohexyl ester, n-heptyl (meth)acrylate, isoheptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate , n-decyl (meth) acrylate, isodecyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate. These may be used singly or in combination of two or more.

The (meth)acrylic polymer is preferably a copolymer of the above alkyl (meth)acrylate and a hydroxyl group-containing (meth)acrylate. In this case, the alkyl group of the alkyl (meth)acrylate is preferably from 1 to 8, more preferably from 2 to 8, further preferably from 2 to 6, particularly preferably from 4 to 6. The alkyl group of the alkyl (meth)acrylate may be linear or branched.

Specific examples of the hydroxyl group-containing (meth) acrylate include 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, and 2-hydroxypropyl (meth)acrylate. , 4-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 5-hydroxypentyl (meth)acrylate, (meth)acrylic acid 3-hydroxy-3-methylbutyl ester, 6-hydroxyhexyl (meth)acrylate, 7-hydroxyheptyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, (meth)acrylic acid 10 - Hydroxy decyl ester, 12-hydroxylauryl (meth)acrylate, (4-hydroxymethylcyclohexyl)-methyl (meth)acrylate, and the like. These may be used singly or in combination of two or more.

The carbon number of the hydroxyalkyl group having a hydroxyl group-containing (meth) acrylate is preferably less than the carbon number of the alkyl group of the alkyl (meth) acrylate. The number of carbon atoms of the hydroxyalkyl group having a hydroxyl group-containing (meth) acrylate is preferably from 1 to 8, more preferably from 2 to 4, still more preferably 2. By adjusting the carbon number of the alkyl group in this manner, the reactivity with the following isocyanate compound can be improved, and it is obtained. An adhesive having further excellent adhesion characteristics.

The copolymerization amount of the above hydroxyl group-containing (meth) acrylate is preferably 0.05 to 20 mol%, more preferably 0.10 to 8 mol%, still more preferably 0.12 to 3 mol%, still more preferably 0.14. ~1.5 mol%, preferably 0.14~0.25 mol%.

The (meth)acrylic polymer may be obtained by copolymerizing other components in addition to the above (meth)acrylic acid alkyl ester or hydroxyl group-containing (meth)acrylic acid ester. The other component is not particularly limited, and (meth)acrylic acid, benzyl (meth)acrylate, methoxyethyl (meth)acrylate, ethoxymethyl (meth)acrylate, ( Phenyloxyethyl methacrylate, (meth) acrylamide, vinyl acetate, (meth) acrylonitrile, and the like. The copolymerization amount of the other components is preferably 100 parts by mass or less, and more preferably 50 parts by mass or less based on 100 parts by mass of the alkyl (meth)acrylate.

The weight average molecular weight (Mw) of the (meth)acrylic polymer is preferably 400,000 or more, more preferably 400,000 or more, by a gel permeation chromatography (GPC) method using a tetrahydrofuran (THF) solvent. 1 million to 3 million, particularly preferably 1.2 million to 2.5 million.

Examples of the isocyanate compound include 2,4-(or 2,6-)toluene diisocyanate, benzenedimethylene diisocyanate, 1,3-bis(isocyanatemethyl)cyclohexane, and hexamethylene Diisocyanate, norbornene diisocyanate, chlorophenyl diisocyanate, tetramethylene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, trimethylolpropane xylene diisocyanate, hydrogenated diphenyl Isocyanate monomer such as methane diisocyanate; an addition type isocyanate compound obtained by adding the isocyanate monomer to a polyol such as trimethylolpropane; an isocyanurate compound; a biuret type compound; a urethane prepolymer type isocyanate obtained by an addition reaction of a suitable polyether polyol or polyester polyol, an acrylic polyol, a polybutadiene polyol, or a polyisoprene polyol These may be used singly or in combination of two or more.

As the above isocyanate compound, a commercially available product can be used as it is. The commercially available isocyanate-based compound may, for example, be manufactured by Mitsui Takeda Chemical Co., Ltd. Takenate series (trade name "D-110N, 500, 600, 700", etc.), Coronate series (trade name "L, MR, EH, HL", etc.) manufactured by Japan Polyurethane Industry Co., Ltd.

Examples of the epoxy compound include N, N, N', N'-tetraglycidyl metaxylylenediamine (trade name: TETRAD-X, manufactured by Mitsubishi Gas Chemical Co., Ltd.), or 1,3-double (manufactured by Mitsubishi Gas Chemical Co., Ltd.). N,N-glycidylaminomethyl)cyclohexane (trade name: TETRAD-C, manufactured by Mitsubishi Gas Chemical Co., Ltd.) and the like.

Examples of the melamine-based resin include hexamethylol melamine and the like. Examples of the aziridine derivative include, for example, commercially available products such as HDU, TAZM, and TAZO (manufactured by Mutual Pharmaceutical Co., Ltd.).

Examples of the metal chelate compound include aluminum, iron, tin, titanium, nickel, and the like as a metal component, and examples thereof include acetylene, ethyl acetonate acetate, and ethyl lactate.

The content of the crosslinking agent used in the present invention is preferably 0.1 to 10 parts by mass, more preferably 0.2 to 4 parts by mass, even more preferably 100 parts by mass based on the above (meth)acrylic polymer. Preferably, it contains 0.3 to 1.5 parts by mass, and most preferably contains 0.4 to 0.9 parts by mass. By setting this content, good adhesion can be obtained even in a harsh (high temperature, high humidity) environment. Further, these crosslinking agents may be used singly or in combination of two or more.

The acrylic adhesive (adhesive composition) preferably further contains a decane coupling agent or a radiation curable component. As the decane coupling agent, for example, a decane coupling agent having any appropriate functional group can be selected. Examples of the functional group include a vinyl group, an epoxy group, a methacryloxy group, an amine group, a decyl group, an acryloxy group, an ethyl oxime group, an isocyanate group, a styryl group, and a polysulfide group. Specific examples of the above decane coupling agent include vinyltrimethoxydecane, γ-glycidoxypropyltrimethoxydecane, γ-glycidoxypropyltriethoxydecane, and benzene. Vinyl trimethoxy decane, γ-methyl propylene methoxy propyl trimethoxy decane, γ-acryloxypropyl trimethoxy decane, N-β (amino group B Γ-aminopropyltrimethoxydecane, γ-aminopropylmethoxydecane, γ-mercaptopropylmethyldimethoxydecane, bis(triethoxycarbamidopropyl)tetra Sulfide, γ-isocyanate propyl trimethoxy decane, and the like. Among these, a decane coupling agent having an epoxy group is preferred, and γ-glycidoxypropyltrimethoxydecane is further preferred.

As the above decane coupling agent, a commercially available product can be used as it is. For example, KA series (trade name "KA-1003", etc.) and KBM series (product name "KBM-303, KBM-403, KBM-503", etc.) manufactured by Shin-Etsu Organic Co., Ltd. And the KBE series (trade name "KBE-402, KBE-502, KBE-903", etc.), the SH series (trade name "SH6020, SH6040, SH6062", etc.) and the SZ series (product name) manufactured by Toray Industries, Inc. SZ6030, SZ6032, SZ6300", etc.).

The content of the decane coupling agent is preferably 0.001 to 2.0 parts by mass, more preferably 0.005 to 2.0 parts by mass, even more preferably 0.01 to 1.0 part by mass, based on 100 parts by mass of the (meth)acrylic polymer. Good is 0.02~0.5 parts by mass. By setting it to such a content, peeling or generation of bubbles can be suppressed even in a harsh (high temperature, high humidity) environment.

As the radiation curable component, a monomer and/or oligomer component which is subjected to radical polymerization or cationic polymerization by irradiation can be used. The monomer component which is subjected to radical polymerization by irradiation may, for example, be a monomer having an unsaturated double bond such as a (meth) acrylonitrile group or a vinyl group, and particularly preferably has an advantage of being excellent in reactivity. A monomer of (meth)acrylonitrile. Specific examples of the monomer component having a (meth) acrylonitrile group include allyl (meth) acrylate, caprolactone (meth) acrylate, and cyclohexyl (meth) acrylate. N)N-diethylaminoethyl acrylate, 2-ethylhexyl (meth)acrylate, heptafluorodecyl (meth)acrylate, glycidyl (meth)acrylate, caprolactone Modified 2-hydroxyethyl (meth)acrylate, isobornyl (meth)acrylate, morpholine (meth)acrylate, phenoxyethyl (meth)acrylate, tripropylene glycol di(meth)acrylic acid Ester, bisphenol A diglycidyl ether di(meth) acrylate, hydroxypivalic acid neopentyl glycol di(meth) acrylate, Trimethylolpropane tri(meth)acrylate, trimethylolpropane ethoxy tris(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol (Meth) acrylate, dipentaerythritol hexa (meth) acrylate, caprolactone-modified dipentaerythritol hexa (meth) acrylate, and the like.

As an oligomer component which is subjected to radical polymerization by irradiation, it is possible to add two or more unsaturated double bonds such as a (meth) acrylonitrile group or a vinyl group to a skeleton such as polyester, epoxy or urethane. A polyester (meth) acrylate, an epoxy (meth) acrylate, a urethane (meth) acrylate or the like which is a functional group similar to the monomer component.

The polyester (meth) acrylate is obtained by reacting (meth)acrylic acid with a polyester having a terminal hydroxyl group obtained from a polyhydric alcohol and a polyvalent carboxylic acid, and specific examples thereof include ARONIX M manufactured by Toagosei Co., Ltd. - 6000, 7000, 8000, 9000 series of polyester acrylates.

Epoxy (meth) acrylate is obtained by reacting (meth)acrylic acid with an epoxy resin, and as a specific example, Ripoxy SP, VR series or Kyoeisha Chemical Co., Ltd. manufactured by Showa Polymer Co., Ltd. Epoxy acrylate of the EPOXYESTER series manufactured by the company.

The urethane (meth) acrylate is obtained by reacting a polyol, an isocyanate, or a hydroxy (meth) acrylate, and a specific example is an Art Resin UN series manufactured by Kasei Kogyo Co., Ltd., and a new one. NK Oligo U series manufactured by Nakamura Chemical Industry Co., Ltd., urethane UV acrylate manufactured by Nippon Synthetic Chemical Industry Co., Ltd.

As the monomer and/or oligomer component for carrying out cationic polymerization, a compound having a cationically polymerizable functional group such as an epoxy group, a hydroxyl group, a vinyl ether group, an episulfide group, or an ethylenimine group is used, in particular For the advantage of excellent reactivity, a compound having an epoxy group is used. Examples of the compound having an epoxy group include a glycidyl ether type epoxy resin produced by a reaction of a polyhydric phenol compound or a polyol with epichlorohydrin. Specifically, it can be listed A diglycidyl ether of bisphenol A or an alkylene oxide adduct thereof, a diglycidyl ether of bisphenol F or an alkylene oxide adduct thereof, hydrogenated bisphenol A or an alkylene oxide adduct thereof Diglycidyl ether, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, butanediol diglycidyl ether, hexanediol diglycidyl ether, Cyclohexane dimethanol diglycidyl ether, polypropylene glycol diglycidyl ether, trimethylolpropane polyglycidyl ether, pentaerythritol polyglycidyl ether, sorbitol polyglycidyl ether, resorcinol Glycidyl ether and the like.

When the (meth)acrylic polymer and the radiation curable component are used in combination as appropriate, if the compatibility (mixing property) is poor, it is difficult to obtain a balance between the adhesion after the radiation curing and the storage elastic modulus, and the light transmittance after the hardening. For reasons such as deterioration in properties, it is necessary to appropriately select a combination having a better compatibility. In particular, in applications requiring light transmittance, the total light transmittance after curing is 85% or more (preferably 90% or more), and the haze value is 10% or less (preferably 5% or less). ). In addition, the amount of the radiation curable component is appropriately adjusted in accordance with the storage elastic modulus and adhesion after radiation curing, and is generally 10 to 200 parts by mass, preferably 30, based on 100 parts by mass of the adhesive polymer. Use in a ratio of ~150 parts by mass.

The amount of the polyfunctional monomer to be used is appropriately selected depending on the balance with the (meth)acrylic polymer and the use as the adhesive sheet. In order to obtain sufficient heat resistance by the cohesive force of the acrylic pressure-sensitive adhesive, it is preferably blended in an amount of 0.1 to 30 parts by mass based on 100 parts by mass of the (meth)acrylic polymer. In addition, it is more preferably 10 parts by mass or less based on 100 parts by mass of the (meth)acryl-based polymer from the viewpoint of flexibility and adhesion.

Examples of the radiation include ultraviolet rays, laser rays, alpha rays, beta rays, gamma rays, x-rays, and electron beams. However, it is preferable to use ultraviolet rays in view of good controllability and workability and cost. It is better to use ultraviolet rays having a wavelength of 200 to 400 nm. The ultraviolet light can be irradiated with a suitable light source such as a high pressure mercury lamp, a microwave excitation lamp, or a chemical lamp. Furthermore, when ultraviolet rays are used as radiation, photopolymerization initiation is added to the acrylic adhesive. Agent.

As the photopolymerization initiator, a radical or a cation may be generated by irradiation of ultraviolet rays having an appropriate wavelength as an initiator of the polymerization reaction, depending on the kind of the radiation-reactive component, as a photoradical polymerization. The starting agent may, for example, be benzoin, benzoin methyl ether, benzoin ethyl ether, o-benzylidene benzoic acid methyl ester, benzoin ethyl ether, benzoin isopropyl ether, α-methyl phenylene Acetophenones such as benzoin, benzoin dimethyl ketal, trichloroacetophenone, 2,2-diethoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone, etc. 2- Phenylacetone, benzophenone, methylbenzophenone, p-chlorobenzophenone, hydroxy-2-methylpropiophenone, 2-hydroxy-4'-isopropyl-2-methylpropiophenone, a thioxanthone such as benzophenone, such as dimethylaminobenzophenone, 2-chlorothioxanthone, 2-ethylthioxanthone or 2-isopropylthioxanthone, or bis (2, 4,6-trimethylbenzimidyl)-phenylphosphine oxide, 2,4,6-trimethylbenzimidyldiphenylphosphine oxide, (2,4,6-trimethylbenzhydrazide Ruthenyl phosphine oxides such as phenyl)-(ethoxy)-phenylphosphine oxide, benzophenone, dibenzo Heptenone, α- acyl oxime ester and the like. Examples of the photocationic polymerization initiator include an onium salt such as an aromatic diazonium salt, an aromatic iodonium salt, or an aromatic onium salt, or an iron-aromatic complex, a titanocene complex, and an arylsulfonium group. Organic metal complexes such as alcohol-aluminum complexes, nitrobenzyl esters, sulfonic acid derivatives, phosphates, sulfonic acid derivatives, phosphates, phenolsulfonates, diazonaphthoquinones, N-hydroxyindoles Imine sulfonate and the like.

The photopolymerization initiator may be used in combination of two or more kinds. The photopolymerization initiator is preferably blended in an amount of usually 0.1 to 10 parts by mass, preferably 0.2 to 7 parts by mass, based on 100 parts by mass of the (meth)acryl-based polymer.

Further, a photopolymerization initiation aid such as an amine may be used in combination. Examples of the photopolymerization initiation aid include 2-dimethylaminoethyl benzoate, dimethylaminoacetophenone, p-dimethylaminobenzoic acid ethyl ester, and p-dimethylamino group. Isoamyl benzoate and the like. The photopolymerization initiation aid may be used in combination of two or more kinds. The polymerization initiation aid is preferably blended in an amount of from 0.05 to 10 parts by mass, more preferably from 0.1 to 7 parts by mass, per 100 parts by mass of the (meth)acryl-based polymer.

<Layering method of first resin layer and second resin layer>

As a method of laminating the first resin layer and the second resin layer, any appropriate method can be employed. In a preferred embodiment, a method of forming an adhesive layer on one resin layer and laminating another resin layer on the adhesive layer may be employed. Further, as a method of forming the adhesive layer, any appropriate method can be employed. As a specific example, the adhesive can be formed by applying the above-mentioned adhesive (adhesive composition solution) to the resin layer and heating it. At the time of coating, the polymer concentration of the acrylic adhesive is preferably adjusted as appropriate by a solvent (for example, ethyl acetate or toluene). The heating temperature is preferably from 20 ° C to 200 ° C, more preferably from 50 ° C to 170 ° C.

The thickness of the resin film (which has a configuration of the first resin layer, the adhesive layer, and the second resin layer in this order) is preferably from 11 μm to 230 μm, more preferably from 50 μm to 110 μm.

<Adhesive layer>

The adhesive sheet of the present invention has the above-mentioned adhesive layer, and the adhesive layer is formed of an adhesive composition, and the adhesive composition can be used without any particular limitation as long as it has adhesiveness. For example, an acrylic adhesive, an urethane adhesive, a polyester adhesive, a synthetic rubber adhesive, a natural rubber adhesive, a polyoxygen adhesive, or the like can be used, and among them, a more preferable one is selected. At least one of a group consisting of a free acrylic adhesive, a urethane adhesive, and a polyester adhesive is particularly preferably an acrylic adhesive using a (meth)acrylic polymer.

When an acrylic adhesive is used for the above adhesive layer, the (meth)acrylic polymer constituting the acrylic adhesive may be a (meth)acrylic monomer having an alkyl group having 1 to 14 carbon atoms. As a raw material monomer constituting the polymer. As the (meth)acrylic monomer, one type or two or more types may be used as a main component. By using the above (meth)acrylic monomer having an alkyl group having 1 to 14 carbon atoms, it is easy to control the adhesion to the adherend (protected material) to be low, and light peelability can be obtained, or Adhesive sheet with excellent peelability. Further, the (meth)acrylic polymer in the present invention means an acrylic polymer and/or a methacrylic polymer, and (meth)acrylate means propylene. Acid esters and / or methacrylates.

Specific examples of the (meth)acrylic monomer having an alkyl group having 1 to 14 carbon atoms include methyl (meth)acrylate, ethyl (meth)acrylate, and (meth)acrylic acid. N-butyl acrylate, second butyl (meth) acrylate, tert-butyl (meth) acrylate, isobutyl (meth) acrylate, hexyl (meth) acrylate, 2-ethyl (meth) acrylate Hexyl ester, n-octyl (meth)acrylate, isooctyl (meth)acrylate, n-decyl (meth)acrylate, isodecyl (meth)acrylate, n-decyl (meth)acrylate, (a) Isodecyl acrylate, n-dodecyl (meth)acrylate, n-tridecyl (meth)acrylate, n-tetradecyl (meth)acrylate, and the like.

In the case where the adhesive sheet of the present invention is used as the surface protective film, examples thereof include hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and n-octyl (meth)acrylate. Isooctyl (meth)acrylate, n-decyl (meth)acrylate, isodecyl (meth)acrylate, n-decyl (meth)acrylate, isodecyl (meth)acrylate, (meth)acrylic acid a (meth)acrylic monomer having an alkyl group having 6 to 14 carbon atoms such as n-dodecyl ester, n-tridecyl (meth)acrylate or n-tetradecyl (meth)acrylate; Better. In particular, by using a (meth)acrylic monomer having an alkyl group having 6 to 14 carbon atoms, it is easy to control the adhesion to the adherend to be low, and it is excellent in removability.

In particular, it is preferably 50% by mass or more, more preferably 60% by mass or more, and still more preferably 70% by mass or more based on 100% by mass of the total of the monomer components constituting the (meth)acrylic polymer. The (meth)acrylic monomer having an alkyl group having 1 to 14 carbon atoms is preferably 80 to 93% by mass. If it is less than 50% by mass, the appropriate wettability of the adhesive composition or the cohesive force of the adhesive layer is deteriorated, which is not preferable.

Further, in the adhesive composition of the present invention, it is preferred that the (meth)acrylic polymer contains a (meth)acrylic monomer having a hydroxyl group as a raw material monomer. As the (meth)acrylic monomer having a hydroxyl group, one type or two or more types may be used as a main component.

By using the above-mentioned (meth)acrylic monomer having a hydroxyl group, it is easy to control the crosslinking of the adhesive composition, etc., and it is easy to control the improvement of the wettability by flow and the balance of the adhesive force in peeling. In addition, unlike a carboxyl group or a sulfonate group which can function as a crosslinking site, a hydroxyl group interacts with an ionic compound which is an antistatic component (antistatic agent), and therefore, in terms of antistatic property, It can also be preferably used.

Examples of the (meth)acrylic monomer having a hydroxyl group include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate. , 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate, (meth)acrylic acid (4-hydroxymethylcyclohexyl)methyl ester, N-methylol (meth) acrylamide, and the like. In particular, by using a (meth)acrylic monomer having a hydroxyl group having 4 or more carbon atoms in the alkyl group, light peeling at the time of high-speed peeling is easy, and therefore it is preferable.

It is preferable to contain 15 parts by mass or less of the above-mentioned (meth)acrylic monomer having a hydroxyl group, and more preferably 100 parts by mass of the (meth)acrylic monomer having an alkyl group having 1 to 14 carbon atoms. It is 1 to 13 parts by mass, more preferably 2 to 11 parts by mass, most preferably 3.5 to 10 parts by mass. When it is in the above range, it is preferred to control the balance between the wettability of the adhesive composition and the cohesive force of the obtained adhesive layer. In addition, in particular, by blending 5 parts by mass or more, an adhesive composition having a preferable creep property can be easily obtained.

In addition, as a reason for the balance of the adhesive properties, it is possible to adjust the glass transition temperature or peeling of the (meth)acrylic polymer in a range that does not impair the effects of the present invention. The polymerizable monomer has a Tg of 0 ° C or lower (usually -100 ° C or higher).

The (meth)acrylic monomer other than the above-mentioned alkyl group having a carbon number of 1 to 14 and the (meth)acrylic monomer having a hydroxyl group, which are used in the above (meth)acrylic polymer, As the polymerizable monomer, a (meth)acrylic monomer having a carboxyl group can be used.

Examples of the (meth)acrylic monomer having a carboxyl group include (meth)acrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, and hexahydrophthalic acid 2- (Meth) propylene methoxyethyl ester, hexahydrophthalic acid 2-(methyl) propylene methoxy propyl ester, 2-(methyl) propylene methoxyethyl phthalate, succinic acid 2 -(Meth)propenyloxyethyl ester, 2-(methyl)propenyloxyethyl maleate, carboxypolycaprolactone mono(meth)acrylate, tetrahydrophthalic acid 2-( Methyl) propylene methoxyethyl ester or the like.

The (meth)acrylic monomer having a carboxyl group is preferably 5 parts by mass or less, more preferably 5 parts by mass or less, based on 100 parts by mass of the (meth)acrylic monomer having an alkyl group having 1 to 14 carbon atoms. 1 part by mass or less, more preferably less than 0.2 part by mass, most preferably 0.01 part by mass or more and less than 0.1 part by mass. In particular, when a (meth)acrylic monomer having a carboxyl group is used in combination with a (meth)acrylic monomer having a hydroxyl group, it may be obtained in terms of an adhesive composition having excellent creep properties. Good to use. In addition, when it exceeds 5 parts by mass, an acid functional group of a carboxyl group having a large interaction exists in a large amount, and when an ionic compound is formulated as an antistatic component, an acid functional group such as a carboxyl group interacts with the ionic compound, thereby hindering Ion conduction, low electrical conductivity, and insufficient antistatic properties are not good. In addition, the above-mentioned (meth)acrylic monomer having a hydroxyl group is contained in an amount of not less than 0.1 part by mass and not more than 0.1 part by mass, in particular, in addition to the above-mentioned creep property and light peeling property. A (meth)acrylic monomer having a carboxyl group is preferred because it can achieve both properties.

Further, as the (meth)acrylic polymer, a (meth)acrylic monomer having an alkyl group having 1 to 14 carbon atoms and a (meth)acrylic monomer having a hydroxyl group, and having The polymerizable monomer other than the carboxyl group-containing (meth)acrylic monomer can be used without particular limitation as long as it does not impair the characteristics of the present invention. For example, a component containing a cyano group-containing monomer, a vinyl ester monomer, an aromatic vinyl monomer or the like which improves cohesive force and heat resistance, or a guanidine-containing monomer, a ruthenium-containing monomer, and an amine may be suitably used. Base monomer, epoxy group-containing monomer, N-propylene morpholine, vinyl ether monomer, etc. to improve adhesion or There are components which function as a functional group of a crosslinking crosslinking point. These polymerizable monomers may be used singly or in combination of two or more.

Examples of the cyano group-containing monomer include acrylonitrile and methacrylonitrile.

Examples of the vinyl ester monomer include vinyl acetate, vinyl propionate, and vinyl laurate.

Examples of the aromatic vinyl monomer include styrene, chlorostyrene, chloromethylstyrene, α-methylstyrene, and other substituted styrenes.

Examples of the guanamine-containing monomer include acrylamide, methacrylamide, diethyl acrylamide, N-vinyl pyrrolidone, N,N-dimethyl decylamine, and N,N-. Dimethyl methacrylamide, N,N-diethyl acrylamide, N,N-diethyl methacrylamide, N,N'-methylenebis propylene amide, N,N- Dimethylaminopropyl acrylamide, N,N-dimethylaminopropyl methacrylamide, diacetone acrylamide, and the like.

Examples of the quinone imine group-containing monomer include cyclohexylmaleimide, isopropylmaleimide, N-cyclohexylmaleimide, and itaconimide.

Examples of the amine group-containing monomer include aminoethyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, and N,N-dimethyl (meth)acrylate. Aminopropyl ester and the like.

Examples of the epoxy group-containing monomer include glycidyl (meth)acrylate, methyl glycidyl (meth)acrylate, and allyl glycidyl ether.

Examples of the vinyl ether monomer include methyl vinyl ether, ethyl vinyl ether, and isobutyl vinyl ether.

In the present invention, in addition to a (meth)acrylic monomer having an alkyl group having 1 to 14 carbon atoms, a (meth)acrylic monomer having a hydroxyl group, or a (meth)acrylic monomer having a carboxyl group. The amount of the other polymerizable monomer is preferably from 0 to 40 parts by mass, more preferably from 0 to 30 parts by mass, per 100 parts by mass of the (meth)acrylic monomer having an alkyl group having 1 to 14 carbon atoms. By using the above other polymerizable monomer in the above range, when an ionic compound is used as an antistatic agent, a good mutual interaction with the above ionic compound can be appropriately adjusted. Role and good re-peelability.

The (meth)acrylic polymer may further contain a reactive monomer containing an alkoxy group as a monomer component. The average addition mole number of the oxygen-extended alkyl unit of the above-mentioned alkoxy group-containing reactive monomer is preferably from 1 to 40 from the viewpoint of compatibility with the ionic compound as an antistatic component. More preferably, it is 3 to 40, further preferably 4 to 35, and particularly preferably 5 to 30. When the average addition molar number is 1 or more, there is a tendency to efficiently obtain an effect of reducing contamination by the adherend (protected object). Further, when the average addition molar number is more than 40, the interaction with the ionic compound is large, and the viscosity of the adhesive composition is increased, which tends to be difficult to apply, which is not preferable. Further, the terminal of the oxygen alkyl chain may be a hydroxyl group itself or may be substituted by another functional group or the like.

The above-mentioned alkoxy group-reactive monomer may be used singly or in combination of two or more kinds thereof, and the content as a whole is preferably 35 mass% or less of the total amount of the monomer components of the (meth)acrylic polymer. It is more preferably 20% by mass or less, further preferably 15% by mass or less, and particularly preferably 5% by mass or less. When the content of the alkoxy group-containing reactive monomer exceeds 35% by mass, when the ionic compound is formulated as an antistatic component, the interaction with the ionic compound becomes large, and ion conduction is hindered, and the antistatic property is lowered. So not good.

Examples of the oxygen-extended alkyl unit having the above-mentioned alkoxy-reactive monomer include those having a C 1 to 6 alkyl group, and examples thereof include an oxygen-extended methyl group, an oxygen-extended ethyl group, and an oxygen-extended propyl group. , oxygen butyl and the like. The hydrocarbyl group of the oxygen alkyl chain may be straight or branched.

Further, the above-mentioned alkoxy group-reactive monomer is more preferably a reactive monomer having an ethoxy group. By using a (meth)acrylic polymer containing a reactive monomer having an ethoxylated epoxy group as a base polymer, compatibility between the base polymer and the ionic compound can be improved, and bleeding to the adherend can be appropriately suppressed. A low-contaminant adhesive composition can be obtained.

As the above-mentioned alkylene-reactive monomer, for example, a (meth)acrylic acid ring is exemplified. An oxane adduct or a reactive surfactant having a reactive substituent such as an acrylonitrile group, a methacryl fluorenyl group or an allyl group in the molecule.

Specific examples of the (meth)acrylic acid alkylene oxide adduct include polyethylene glycol (meth) acrylate, polypropylene glycol (meth) acrylate, and polyethylene glycol-polypropylene glycol (A). Acrylate, polyethylene glycol-polybutylene glycol (meth) acrylate, polypropylene glycol-polybutylene glycol (meth) acrylate, methoxy polyethylene glycol (meth) acrylate, B Oxypoly polyethylene glycol (meth) acrylate, butoxy polyethylene glycol (meth) acrylate, octyloxy polyethylene glycol (meth) acrylate, lauryl oxy polyethylene glycol (A Acrylate, stearyloxy polyethylene glycol (meth) acrylate, phenoxy polyethylene glycol (meth) acrylate, methoxy polypropylene glycol (meth) acrylate, octyloxy poly Ethylene glycol-polypropylene glycol (meth) acrylate or the like.

Further, specific examples of the reactive surfactant include an anionic reactive surfactant having a (meth)acryl fluorenyl group or an allyl group, a nonionic reactive surfactant, and a cationic reaction. Sexual surfactants, etc.

The weight average molecular weight (Mw) of the (meth)acrylic polymer is preferably from 100,000 to 5,000,000, more preferably from 200,000 to 2,000,000, and still more preferably from 300,000 to 1,000,000. When the weight average molecular weight is less than 100,000, the cohesive force of the adhesive layer is reduced, so that there is a tendency for the paste to remain. On the other hand, when the weight average molecular weight exceeds 5 million, the fluidity of the polymer is lowered, the wetting of the adherend (for example, a polarizing plate) is insufficient, and the adhesion between the adherend and the adhesive sheet is caused. The tendency to bulge between the layers of the agent. Further, the weight average molecular weight means a person obtained by gel permeation chromatography (GPC) measurement.

Further, the glass transition temperature (Tg) of the (meth)acrylic polymer is preferably 0 ° C or lower, more preferably -10 ° C or lower (generally -100 ° C or higher). When the glass transition temperature is higher than 0 ° C, the polymer hardly flows, for example, the wetting of the polarizing plate becomes insufficient, and there is a tendency to cause bulging between the polarizing plate and the adhesive layer of the adhesive sheet. In particular, by setting the glass transition temperature to -61 ° C or lower, it is easy to obtain wettability to the polarizing plate. And an adhesive layer excellent in light peelability. Further, the glass transition temperature of the (meth)acrylic polymer can be adjusted within the above range by appropriately changing the monomer component or composition ratio used.

The polymerization method of the (meth)acrylic polymer is not particularly limited, and polymerization can be carried out by a known method such as solution polymerization, emulsion polymerization, bulk polymerization or suspension polymerization, in particular, from the viewpoint of workability or The solution polymerization is a better aspect in terms of characteristics such as low contamination of the body (protected material). Further, the obtained polymer may be any of a random copolymer, a block copolymer, an alternating copolymer, a graft copolymer and the like. Further, the polymerization conditions, the polymerization solvent, the polymerization initiator, and the like can be appropriately used based on a known technique.

When a urethane-based pressure-sensitive adhesive is used as the pressure-sensitive adhesive layer, any suitable urethane-based pressure-sensitive adhesive can be used as the urethane-based pressure-sensitive adhesive. As such a urethane-based adhesive, a urethane resin obtained by reacting a polyol with a polyisocyanate is preferably used. Examples of the polyhydric alcohol include a polyether polyol, a polyester polyol, a polycarbonate polyol, and a polycaprolactone polyol. Examples of the polyisocyanate-based compound include diphenylmethane diisocyanate, toluene diisocyanate, and hexamethylene diisocyanate.

When a polyester-based adhesive is used for the above-mentioned adhesive layer, any suitable polyester-based adhesive can be used as the polyester-based adhesive. Examples of the polyester-based pressure-sensitive adhesive include polyesters obtained by polycondensing a carboxylic acid component having two or more functional groups and a diol component. Examples of the carboxylic acid component include azelaic acid, dimer acid derived from oleic acid, erucic acid, or the like, adipic acid, sebacic acid, 1,4-cyclohexanedicarboxylic acid, and 4-methyl-1. , 2-cyclohexanedicarboxylic acid, dodecenyl succinic anhydride, fumaric acid, succinic acid, dodecanedioic acid, hexahydrophthalic acid, tetrahydrophthalic acid, maleic acid, Malay An aliphatic or alicyclic dicarboxylic acid such as an acid anhydride, itaconic acid or citraconic acid, or terephthalic acid, isophthalic acid, phthalic acid, 1,5-naphthalene dicarboxylic acid, 2,6- Naphthalenedicarboxylic acid, 4,4'-diphenyldicarboxylic acid, 2,2'-diphenyl Formic acid, 4,4'-diphenyl ether dicarboxylic acid, and the like. Examples of the diol component include an aliphatic diol or a polyether diol.

<Antistatic component in the adhesive layer>

In the adhesive sheet of the present invention, the adhesive composition constituting the pressure-sensitive adhesive layer preferably contains an antistatic component, and more preferably contains an ionic compound as the antistatic component. Examples of the ionic compound include an alkali metal salt and/or an ionic liquid having a melting point of 100 ° C or lower. By containing the plasma liquid, excellent antistatic properties can be imparted. In addition, the adhesive layer (using an antistatic component) obtained by crosslinking the adhesive composition containing an antistatic component as described above can be used for an adherend (for example, a polarizing plate) which is not subjected to an antistatic treatment at the time of peeling. Antistatic is an adhesive sheet that reduces contamination of the adherend. Therefore, it is very useful as an antistatic adhesive sheet in the technical field related to optical or electronic parts in which static electricity or contamination is a particularly serious problem.

In addition, the content of the antistatic component is preferably 4.9 parts by mass or less, more preferably 0.001 to 0.9 parts by mass, even more preferably 0.005 to 0.8 parts by mass, based on 100 parts by mass of the (meth)acrylic polymer. Preferably, it is 0.01 to 0.5 parts by mass. If it is in the above range, it is easy to achieve both antistatic property and low contamination, and therefore it is preferable.

<crosslinker>

In the adhesive sheet of the present invention, it is preferred that the adhesive composition contains a crosslinking agent. Further, in the present invention, the above adhesive composition can be used to form an adhesive layer. For example, when the above-mentioned (meth)acrylic polymer is contained in the above-mentioned adhesive, the constituent unit of the (meth)acrylic polymer, the constituent ratio, the selection of the crosslinking agent, the addition ratio, and the like are appropriately adjusted. Cross-linking provides an adhesive sheet (adhesive layer) which is more excellent in heat resistance.

As the crosslinking agent used in the present invention, an isocyanate compound, an epoxy compound, a melamine resin, an aziridine derivative, a metal chelate compound or the like can be used. In particular, the use of an isocyanate compound is preferred. Further, these compounds may be used singly or in combination of two or more.

Examples of the isocyanate compound (isocyanate-based crosslinking agent) include aliphatic polyisocyanates such as trimethylene diisocyanate, butyl diisocyanate, hexamethylene diisocyanate (HDI), and dimer acid diisocyanate. Cycloaliphatic diisocyanate, cyclohexyl diisocyanate, isophorone diisocyanate (IPDI) and other alicyclic isocyanates, 2,4-toluene diisocyanate, 4,4'-diphenylmethane diisocyanate, benzene An aromatic isocyanate such as dimethylene diisocyanate (XDI), an allophanate bond, a biuret bond, an isocyanurate bond, a uretdione bond, a urea bond, a carbodiimide bond, A polyisocyanate modified product obtained by modifying the above isocyanate compound, such as a uretonimine bond or a oxadiazine triketone bond. For example, commercially available products include TAKENATE 300S, TAKENATE 500, TAKENATE D165N, TAKENATE D178N (above, manufactured by Takeda Pharmaceutical Co., Ltd.), Sumidur T80, Sumidur L, and Desmodur N3400 (the above is manufactured by Sumitomo Bayer Co., Ltd.). ), Millionate MR, Millionate MT, Coronate L, Coronate HL, Coronate HX (above, manufactured by Japan Polyurethane Industry Co., Ltd.), and the like. These isocyanate compounds may be used singly or in combination of two or more kinds, and a bifunctional isocyanate compound and a trifunctional or higher isocyanate compound may be used in combination. By using the crosslinking agent in combination, it is possible to achieve both stable adhesion and resilience (adhesion to a curved surface), and an adhesive sheet having more excellent reliability can be obtained.

In the case where a bifunctional isocyanate compound and a trifunctional or higher isocyanate compound are used in combination as the isocyanate compound (isocyanate crosslinking agent), the compounding ratio (mass ratio) of the two compounds is preferably [2]. The functional isocyanate compound]/[3 functional or higher isocyanate compound] (mass ratio) is 0.1/99.9 to 50/50, more preferably 0.1/99.9 to 20/80, and still more preferably 0.1/99.9 to 10/90. It is particularly preferably 0.1/99.5 to 5/95, and most preferably 0.1/99.9 to 1/99. It is preferable to use an adhesive layer which is excellent in adhesiveness and resilience by adjusting and blending in the above range.

Examples of the epoxy compound include N, N, N', N'-tetraglycidyl groups. Xylylenediamine (trade name TETRAD-X, manufactured by Mitsubishi Gas Chemical Co., Ltd.), or 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane (trade name TETRAD-C, Mitsubishi Gas Chemical company manufacturing) and so on.

Examples of the melamine-based resin include hexamethylol melamine and the like. Examples of the aziridine derivative include, for example, commercially available products such as HDU, TAZM, and TAZO (the above are manufactured by Mutual Pharmaceutical Co., Ltd.).

Examples of the metal chelate compound include aluminum, iron, tin, titanium, nickel, and the like as a metal component, and examples thereof include acetylene, ethyl acetonate acetate, and ethyl lactate.

The content of the crosslinking agent used in the present invention is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 8 parts by mass, even more preferably 100 parts by mass based on 100 parts by mass of the (meth)acrylic polymer. It is contained in an amount of 0.5 to 6 parts by mass, preferably 1.0 to 4.5 parts by mass. When the content is less than 0.01 parts by mass, crosslinking by the crosslinking agent may be insufficient, and the cohesive force of the obtained adhesive layer may be low, and sufficient heat resistance may not be obtained, and The tendency of the paste to remain. On the other hand, when the content exceeds 10 parts by mass, the cohesive force of the polymer is large, the fluidity is lowered, and the wetting of the adherend (for example, a polarizing plate) is insufficient, resulting in adhesion of the adherend and adhesion. The tendency of the agent layer (adhesive composition layer) to bulge. Further, when the amount of the crosslinking agent is large, the peeling static characteristics tend to be lowered. Further, these crosslinking agents may be used singly or in combination of two or more.

Further, the above-mentioned adhesive composition may further contain a crosslinking catalyst for allowing the crosslinking reaction to be carried out more efficiently. As the crosslinking catalyst, for example, tin-based catalyst such as dibutyltin dilaurate or dioctyltin dilaurate, tris(acetonitrile)iron, and tris(hexane-2,4-dione) can be used. Iron, tris(heptane-2,4-dione) iron, tris(heptane-3,5-dione) iron, tris(5-methylhexane-2,4-dione) iron, tri ( Octane-2,4-dione)iron, tris(6-methylheptane-2,4-dione)iron, tris(2,6-dimethylheptane-3,5-dione)iron , tris(decane-2,4-dione)iron, tris(decane-4,6-dione)iron, tris(2,2,6,6-tetramethylheptane-3,5-di Ketone) iron, three (ten Trioxane-6,8-dione)iron, tris(1-phenylbutane-1,3-dione)iron, tris(hexafluoroacetamidineacetone)iron, tris(acetate ethyl acetate)iron, Tris(n-acetate acetate) iron, tris(isopropyl acetate) iron, tris(butylammonium acetate n-butyl) iron, tris(acetonitrile acetate dibutyl ester) iron, tris(acetonitrile acetic acid) Third butyl ester) iron, tris(propyl acetate methyl) iron, tris(ethyl acetate) iron, tris(n-propyl acetate) iron, tris(isopropyl acetate) iron, three (n-butyl acetate) iron, tributyl (propionate dibutyl acrylate) iron, tris(butyl acetoxyacetate) iron, tris(ethyl acetonitrile acetate) iron, tris (malonic acid II) Methyl ester) Iron-based catalysts such as iron, tris(diethyl malonate) iron, trimethoxy iron, triethoxy iron, triisopropoxy iron, and ferric chloride. These crosslinking catalysts may be used alone or in combination of two or more.

The content (amount of use) of the crosslinking catalyst is not particularly limited. For example, it is preferably 0.0001 to 1 part by mass, more preferably 0.001 to 0.5 part by mass, per 100 parts by mass of the (meth)acrylic polymer. . If it is within the above range, the crosslinking reaction speed is faster when the adhesive layer is formed, and the pot life of the adhesive composition is also longer, which is preferable.

Further, the above-mentioned adhesive composition may further contain other known additives, and for example, a powder such as a coloring agent or a pigment, a surfactant, a plasticizer, a tackifier, a low molecular weight polymer, or the like may be appropriately added depending on the intended use. Surface lubricants, leveling agents, antioxidants, corrosion inhibitors, light stabilizers, ultraviolet absorbers, polymerization inhibitors, decane coupling agents, inorganic or organic fillers, metal powders, particulates, foils, and the like.

The adhesive sheet of the present invention is formed by forming the above adhesive layer on the second resin layer. At this time, the crosslinking of the adhesive composition is generally performed after the application of the adhesive composition, and may also be included. The adhesive layer of the bonded adhesive composition is transferred onto a resin layer or the like.

Further, the method of forming the adhesive layer on the second resin layer is not particularly limited. For example, the adhesive composition (solution) can be applied onto the resin layer, and the polymerization solvent or the like can be dried to remove the polymerization solvent or the like. An adhesive layer is formed thereon to be fabricated. Then, curing can be performed for the adjustment of the component transfer of the adhesive layer or the adjustment of the crosslinking reaction. In addition, it will stick When the adhesive composition is applied to the resin layer to form an adhesive sheet, one or more solvents other than the polymerization solvent may be newly added to the adhesive composition to be uniformly applied to the resin layer.

Further, as a method of forming the adhesive layer in the production of the adhesive sheet of the present invention, a known method used in the production of an adhesive tape can be used. Specific examples thereof include roll coating, gravure coating, reverse coating, roll brushing, spray coating, air knife coating, extrusion coating using a die coater, and the like.

Usually, the thickness of the above-mentioned adhesive layer is 3 μm to 100 μm, preferably about 5 μm to 50 μm. When the thickness of the adhesive layer is within the above range, it is easy to obtain a balance between moderate re-peelability and adhesion (adhesion), which is preferable.

<separator>

In the adhesive sheet of the present invention, the spacer may be attached to the surface of the adhesive layer for the purpose of protecting the adhesive surface as needed.

As a material constituting the separator, there is a paper or a plastic film, but a plastic film is preferably used in terms of excellent surface smoothness. The film is not particularly limited as long as it can protect the pressure-sensitive adhesive layer, and examples thereof include a polyethylene film, a polypropylene film, a polybutene film, a polybutadiene film, a polymethylpentene film, and a poly A vinyl chloride film, a vinyl chloride copolymer film, a polyethylene terephthalate film, a polybutylene terephthalate film, a polyurethane film, an ethylene-vinyl acetate copolymer film, or the like.

The thickness of the separator is usually from 5 μm to 200 μm, preferably from about 10 μm to 100 μm. When it is in the above range, the adhesiveness on the adhesive layer and the peeling workability from the adhesive layer are excellent, which is preferable. The separator may be subjected to demolding and antifouling treatment by using a polyfluorene-based release agent, a fluorine-based release agent, a long-chain alkyl-based release agent, a fatty amide-based release agent, or a cerium oxide powder as needed. Or antistatic treatment such as coating type, kneading type, or vapor deposition type.

<Face coating (antistatic layer)>

The adhesive sheet of the present invention is characterized by having a first resin layer, an adhesive layer, a second resin layer, and an adhesive layer formed of the adhesive composition, and further comprising the above adhesive agent on the first resin layer The surface on the opposite side of the layer has a top coat layer comprising a polyaniline sulfonic acid as a conductive polymer component, a polyester resin as a binder component, and an isocyanate compound as a crosslinking agent. The composition for topcoat is formed. Since the above-mentioned adhesive sheet has a top coat layer, the antistatic property of the adhesive sheet is improved, which is a preferable aspect.

<Electrically conductive polymer>

The top coat layer is characterized by containing polyaniline sulfonic acid as a conductive polymer component. By using the above-mentioned conductive polymer, the antistatic property based on the top coat layer and the antistatic property over time can be satisfied. Further, the polyaniline sulfonic acid-based "water-soluble" can be immobilized in the top coat layer by using the following isocyanate-based crosslinking agent, and water resistance can be improved. A surface coating layer excellent in surface resistivity over time can be obtained by using an aqueous solution containing the above water-soluble conductive polymer, which is preferable. On the other hand, when the conductive polymer used for forming the top coat layer is "water-dispersible", when a top coat layer is formed using a solution containing the water-dispersible conductive polymer, aggregates are likely to be formed. The coating cannot be uniformly applied, and the surface resistivity with time tends to be remarkably deteriorated, which is not preferable.

The amount of the conductive polymer to be used is preferably 10 to 200 parts by mass, more preferably 25 to 150 parts by mass, even more preferably 40 to 120 parts by mass, per 100 parts by mass of the binder contained in the top coat layer. . When the amount of the conductive polymer used is too small, the antistatic effect may be small, and if the amount of the conductive polymer used is too large, the adhesion between the top coat layer and the resin layer may be lowered, or the transparency may be lowered. So not good.

The polyaniline sulfonic acid used as the conductive polymer component has a weight average molecular weight (Mw) in terms of polystyrene of preferably 5 × 10 ⁵ or less, more preferably 3 × 10 ⁵ or less. Further, the weight average molecular weight of the conductive polymers is usually preferably 1 × 10 ³ or more, more preferably 5 × 10 ³ or more.

As a method of forming the above-mentioned top coat layer, a composition for a top coat layer (a coating material for forming a top coat layer) may be applied to a first surface of a resin layer (base material or a support) and dried (or The method of curing, as a conductive polymer component for preparing a composition for topcoat, contains polyaniline sulfonic acid, a polyester resin as a binder, and an isocyanate crosslinking agent as a crosslinking agent as necessary As the component, the above-mentioned essential component can be preferably used in a form dissolved in water (a conductive polymer aqueous solution or simply an aqueous solution). The conductive polymer aqueous solution can be prepared, for example, by dissolving a conductive polymer having a hydrophilic functional group (which can be synthesized by a method of copolymerizing a monomer having a hydrophilic functional group in the molecule) in water. Examples of the hydrophilic functional group include a sulfo group, an amine group, a decylamino group, an imido group, a hydroxyl group, a decyl group, a decyl group, a carboxyl group, a quaternary ammonium group, a sulfate group (-O-SO ₃ H), and a phosphoric acid group. An ester group (for example, -O-PO(OH) ₂ ) or the like. The above hydrophilic functional group can form a salt.

In addition, as a commercial item of the above-mentioned polyaniline sulfonic acid aqueous solution, the brand name "aqua-pass" manufactured by Mitsubishi Rayon Co., Ltd., etc. can be illustrated.

The top coat layer disclosed herein contains polyaniline sulfonic acid (polyaniline type) as a conductive polymer component as an essential component, but may, for example, contain one or more other antistatic components (conductive polymer) Other than organic conductive materials, inorganic conductive materials, antistatic agents, etc.). Further, as a preferred aspect, the top coat layer does not substantially contain an antistatic component other than the conductive polymer. That is, it is more preferable to carry out the aspect in which the antistatic component contained in the above-mentioned top coat layer substantially contains only the conductive polymer.

Examples of the organic conductive material include a cationic antistatic agent having a cationic functional group such as a quaternary ammonium salt, a pyridinium salt, a first amine group, a second amine group, and a third amine group; a sulfonate or sulfuric acid; Anionic antistatic agent having anionic functional groups such as ester salts, phosphonates, and phosphate ester salts; zwitterionic prevention of alkylbetaine and its derivatives, imidazoline and its derivatives, alanine and its derivatives Electrostatic agent; nonionic antistatic agent such as amino alcohol and its derivatives, glycerin and its derivatives, polyethylene glycol and its derivatives; and the above-mentioned cationic, anionic, zwitterionic ionic conductive group (eg quaternary ammonium salt base) An ion conductive polymer obtained by polymerization or copolymerization of a monomer; a conductive polymer such as polythiophene, polyaniline, polypyrrole, polyethylenimine or allylamine polymer; These antistatic agents may be used alone or in combination of two or more.

Examples of the inorganic conductive material include tin oxide, antimony oxide, indium oxide, cadmium oxide, titanium oxide, zinc oxide, indium, tin, antimony, gold, silver, copper, aluminum, nickel, chromium, titanium, iron, and the like. Cobalt, copper iodide, ITO (indium oxide/tin oxide), ATO (antimony oxide/tin oxide), and the like. These inorganic conductive materials may be used alone or in combination of two or more.

Examples of the antistatic agent include a cationic antistatic agent, an anionic antistatic agent, a zwitterionic antistatic agent, and a nonionic antistatic agent, and the above-mentioned cationic, anionic, and zwitterionic ionic conductive materials are mentioned. An ion conductive polymer obtained by polymerization or copolymerization of a monomer of a group.

<Binder>

The top coat layer is characterized in that it contains a polyester resin as a binder as an essential component. The polyester resin is a resin material containing polyester as a main component (typically, it accounts for more than 50 mass%, preferably 75 mass% or more, for example, 90 mass% or more). The above polyester is preferably preferably a polycarboxylic acid (typically a dicarboxylic acid) having two or more carboxyl groups selected from one molecule and a derivative thereof (an acid anhydride, an esterified product, a hydrazine of the polycarboxylic acid) One or more compounds (polycarboxylic acid component) of one or more of halogen or the like and one or more selected from polyols (typically diols) having two or more hydroxyl groups in one molecule The structure in which the compound (polyol component) is condensed.

Examples of the compound which can be used as the above polyvalent carboxylic acid component include oxalic acid, malonic acid, difluoromalonic acid, alkylmalonic acid, succinic acid, tetrafluorosuccinic acid, alkylsuccinic acid, (± )-Malic acid, meso-tartaric acid, itaconic acid, maleic acid, methyl maleic acid, fumaric acid, methyl fumaric acid, acetylene dicarboxylic acid, glutaric acid, hexafluoroglutaric acid, methyl Glutaric acid, glutaconic acid, adipic acid, dithioadipate, methyl adipate, dimethyl hexane Acid, tetramethyladipate, methylene adipate, hexadiene diacid, galactose diacid, pimelic acid, suberic acid, perfluorooctanedioic acid, 3,3,6,6-tetra Aliphatic dicarboxylic acids such as methyl suberic acid, azelaic acid, sebacic acid, perfluorosebacic acid, tridecanedioic acid, tetradecanedioic acid, pentadecanedioic acid, and hexadecandioic acid Cycloalkyl dicarboxylic acid (for example, 1,4-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid), 1,4-(2-norbornene) dicarboxylic acid, 5-norbornene An alicyclic dicarboxylic acid such as -2,3-dicarboxylic acid (nadic acid), adamantane dicarboxylic acid or spiroheptane dicarboxylic acid; phthalic acid, isophthalic acid, dithioisophthalic acid, Methyl isophthalic acid, dimethyl isophthalic acid, chloroisophthalic acid, dichloroisophthalic acid, terephthalic acid, methyl terephthalic acid, dimethyl terephthalic acid, chlorine Phthalic acid, bromine terephthalic acid, naphthalene dicarboxylic acid, oxonium dicarboxylic acid, phthalic acid dicarboxylic acid, diphenyl phthalic acid, diphenylene dicarboxylic acid, dimethyl phenylene dicarboxylic acid, 4,4"-pair Phenyl dicarboxylic acid, 4,4"-p-tetracarboxylic acid, bibenzyl dicarboxylic acid, azobenzene , high phthalic acid, phenylenediacetic acid, phenyldipropionic acid, naphthalenedicarboxylic acid, naphthalene dipropionic acid, biphenyl diacetic acid, biphenyl dipropionic acid, 3,3'-[4,4' - (methylene di-p-phenyl) dipropionic acid], 4,4'-bibenzyl diacetic acid, 3,3'-(4,4'-bibenzyl) dipropionic acid, oxydi-p-phenylene An aromatic dicarboxylic acid such as diacetic acid; an acid anhydride of any one of the above polycarboxylic acids; an ester of any of the above polycarboxylic acids (for example, an alkyl ester, which may be a monoester or a diester); and any of the above polycarboxylic acids Corresponding to the halogen (for example, dicarboxylic acid ruthenium chloride); and the like.

Preferable examples of the compound which can be used as the polyvalent carboxylic acid component include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid and naphthalene dicarboxylic acid, and acid anhydrides thereof; adipic acid and sebacic acid; An aliphatic dicarboxylic acid such as azelaic acid, succinic acid, fumaric acid, maleic acid, nadic acid, 1,4-cyclohexanedicarboxylic acid or the like; and an acid anhydride thereof; and a lower alkyl group of the above dicarboxylic acid An ester (for example, an ester of a monohydric alcohol having 1 to 3 carbon atoms).

On the other hand, examples of the compound which can be used as the above polyol component include ethylene glycol, propylene glycol, 1,2-propylene glycol, 1,3-propanediol, 1,3-butanediol, and 1,4- Butylene glycol, neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, 3-methylpentanediol, diethylene glycol, 1,4-cyclohexanedimethanol, 3- Methyl-1,5-pentanediol, 2-methyl-1,3-propanediol, 2,2- Diols such as diethyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol, benzenedimethanol, hydrogenated bisphenol A, and bisphenol A. As another example, an alkylene oxide adduct of such a compound (for example, an ethylene oxide adduct, a propylene oxide adduct, etc.) is mentioned.

Molecular weight of the polyester resin, in measurement by gel permeation chromatography (GPC) of the weight average molecular weight of standard polystyrene (Mw) basis, may, for example, about ^{5 × 10 3 ~ 1.5 × 10} 5 ( more Good is 1×10 ⁴ ~6×10 ⁴ or so). Further, the glass transition temperature (Tg) of the above polyester resin may be, for example, 0 ° C to 120 ° C (preferably 10 ° C to 80 ° C).

As the polyester resin, a commercially available product name "Vylonal" manufactured by Toyobo Co., Ltd., or the like can be used.

The top coat layer may further contain a resin selected from the group consisting of polyester resins (for example, selected from the group consisting of acrylic resins, acrylic acid), within the limits of not impairing the properties of the adhesive sheet disclosed herein (for example, properties such as antistatic properties). One of a urethane resin, an acrylic-styrene resin, an acrylic-polyoxynoxy resin, a polyoxyxylene resin, a polyazide resin, a polyurethane resin, a fluororesin, a polyolefin resin, or the like or Two or more resins) as a binder. As a preferred aspect of the technology disclosed herein, the adhesive of the top coat comprises substantially only the polyester resin. For example, a top coat layer in which the proportion of the polyester resin in the binder is 98 to 100% by mass is preferable. The proportion of the binder in the entire top coat layer can be, for example, 50 to 95% by mass, and usually 60 to 90% by mass.

<Lubricant>

The topcoats of the techniques disclosed herein use fatty guanamine as the lubricant as a preferred aspect. By using the fatty guanamine as a lubricant, even if the surface of the top coat layer is not subjected to further release treatment (for example, a known release treatment agent such as a polyoxymethylene release agent or a long-chain alkyl release agent is applied and dried) In the case of the treatment, a top coat having sufficient lubricity and printing adhesion can be obtained, and thus it can be a preferable aspect. Therefore, the surface of the top coat layer is subjected to a further peeling treatment, and the whitening caused by the peeling treatment agent (for example, whitening caused by storage under heating and humidification conditions) can be prevented. It is better in terms of face. In addition, it is also advantageous in terms of solvent resistance.

Specific examples of the above fatty guanamine include laurylamine, palmitoylamine, stearylamine, behenamide, hydroxystearamide, ceramide, cuminamine, and N-oleyl palmitate. Guanamine, N-stearyl stearylamine, N-stearyl decylamine, N-oleyl stearylamine, N-stearyl mustardamine, hydroxymethyl stearylamine, sub Methyl bis- stearylamine, ethyl bis-indoleamine, ethyl bis-laurosamine, ethyl bis-stearylamine, ethyl bishydroxystearylamine, ethyl bis-hydrazine Amine, hexamethylene distearylamine, hexamethylenebis behenamide, hexamethylene bishydroxystearylamine, N,N'-distearate adipate diamine, N , N'-distearyl azelaic acid diammoniumamine, ethyl oleate, ethyl erucic acid, hexamethylene bis-indolylamine, N, N'-dioleyl Didecyl diamine, N,N'-dioleyl sebacate, m-decylamine, m-xylylenebisstearylamine, m-xylylenedihydroxystearylamine, N,N '-Distearyl metabenzamide and the like. These lubricants may be used alone or in combination of two or more.

The proportion of the lubricant in the entire top coat layer can be set to 1 to 50% by mass, and usually 5 to 40% by mass is suitable. If the content ratio of the lubricant is too small, the lubricity tends to be lowered. If the content ratio of the lubricant is too large, the printing adhesion may be lowered.

The technique disclosed herein can be carried out in such a manner that the top coat layer contains other lubricants in addition to the above-mentioned fatty guanamine, within the range which does not significantly impair the application effect. Examples of the other lubricants include various waxes such as petroleum waxes (such as paraffin wax), mineral waxes (such as montan wax), higher fatty acids (such as wax acid), and neutral fats (such as glycerol palmitate). Alternatively, in addition to the above wax, a general polyoxane-based lubricant, a fluorine-based lubricant or the like may be contained. The technique disclosed herein can be preferably carried out in a manner that does not substantially contain the above-mentioned polyfluorene-based lubricant, fluorine-based lubricant or the like. However, the use of a polymer which is used for purposes other than a lubricant (for example, as a defoaming agent for a surface coating composition described below) is not excluded insofar as it does not significantly impair the application effect of the technique disclosed herein. Oxygenation Things.

<crosslinker>

The top coat layer is characterized by containing an isocyanate crosslinking agent as a crosslinking agent. By using the above-mentioned isocyanate-based crosslinking agent, the water-soluble polyaniline sulfonic acid which is an essential component can be immobilized in the binder when the top coat layer is formed, and the effect of excellent water resistance and improved printing adhesion can be achieved.

Further, a preferred aspect is a blocked isocyanate crosslinking agent which is stable in an aqueous solution as the above-mentioned isocyanate crosslinking agent. Specific examples of the blocked isocyanate crosslinking agent include alcohols, phenols, thiophenols, amines, quinones, anthraquinones, indoleamines, and active methylene compounds. Isocyanate-based crosslinking agents which can be used in the preparation of general adhesive layers or top coats such as mercaptans, imines, ureas, diaryl compounds, and sodium hydrogen sulfite (for example, the following adhesives) The isocyanate compound (isocyanate crosslinking agent) used in the layer is blocked.

The top coat in the technology disclosed herein may contain an antioxidant, a colorant (pigment, dye, etc.), a fluidity adjuster (thixotropic agent, a thickener, etc.), a film forming aid, and a surfactant (as needed) as needed. Additives such as defoamers, preservatives, UV absorbers, dispersants, anti-blocking agents, etc.

<Formation of top coat>

The top coat layer can be suitably used as a liquid composition (top coat composition) obtained by dissolving an essential component such as the above-mentioned conductive polymer component and an additive used as needed in a suitable solvent (water or the like). A method of imparting to the resin layer is formed. For example, a method in which the above-mentioned top coating composition is applied onto the first surface of the resin layer, dried, and subjected to a curing treatment (heat treatment, ultraviolet treatment, or the like) as needed is preferably employed. The NV (nonvolatile content) of the top coating composition can be adjusted to, for example, 5% by mass or less (typically 0.05 to 5% by mass), and usually adjusted to 1% by mass or less (typically 0.10 to 1% by mass). %) is more appropriate. In the case of forming a surface coating having a small thickness, it is preferred to apply the above surface coating The NV of the composition is, for example, 0.05 to 0.50% by mass (for example, 0.10 to 0.40% by mass). By using such a low NV topcoat composition, a more uniform topcoat can be formed.

The solvent constituting the composition for a top coat layer (coating material for forming a top coat layer) is preferably one which can stably dissolve the constituent component of the top coat layer. The above solvent may be an organic solvent, water or a mixed solvent of these. As the organic solvent, for example, an ester system selected from the group consisting of ethyl acetate; a ketone such as methyl ethyl ketone, acetone or cyclohexanone; a cyclic ether such as tetrahydrofuran (THF) or dioxane; An aliphatic or alicyclic hydrocarbon such as an alkane or a cyclohexane; an aromatic hydrocarbon such as toluene or xylene; an aliphatic or alicyclic alcohol such as methanol, ethanol, n-propanol, isopropanol or cyclohexanol; One or more of alkyl glycol monoalkyl ethers (for example, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether), dialkyl alkyl glycol monoalkyl ethers, and the like, and the like. In a preferred embodiment, the solvent for the topcoat composition is water or a mixed solvent containing water as a main component (for example, a mixed solvent of water and ethanol).

<Properties of top coat>

The thickness of the top coat in the technique disclosed herein is typically from 3 nm to 500 nm, preferably from 10 nm to 100 nm, more preferably from 20 nm to 60 nm. If the thickness of the top coat layer is too small, it is difficult to uniformly form the top coat layer (for example, the thickness difference varies depending on the portion of the top coat layer), and thus the appearance of the adhesive sheet may be sometimes easy. Produce unevenness. On the other hand, when the thickness is too thick, the properties (optical characteristics, dimensional stability, and the like) of the resin layer may be affected.

In a preferred aspect of the adhesive sheet disclosed herein, the surface resistivity (Ω/□) measured on the surface of the top coat layer is preferably less than 1.0 × 10 ¹¹ , more preferably less than 5.0 × 10 ¹⁰ , and further preferably less than 1.5 × ¹⁰ 10. The adhesive sheet which exhibits the surface resistivity in the above range can be suitably used, for example, as an adhesive sheet used for processing or transporting a liquid-repellent article such as a liquid crystal cell or a semiconductor device. Further, the surface resistivity can be calculated from the surface resistivity measured under an atmosphere of 23 ° C and 50% RH using a commercially available insulation resistance measuring device.

The adhesive sheet disclosed herein preferably has the property that the back surface (the surface of the top coat) can be easily printed using an aqueous ink or an oily ink (for example, using an oil-based marker). The adhesive sheet is described in the above-mentioned adhesive sheet, in which the identification number of the adherend to be protected, etc., is applied to the adhesive sheet in the process of processing or transporting the adherend (for example, an optical component) in a state in which the adhesive sheet is attached. And display it. Therefore, an adhesive sheet excellent in printability is preferable. For example, it is preferred that the oil-based ink of a type in which the solvent is alcohol-based and contains a pigment has high printing property. Further, it is preferable that the ink after printing is not easily removed by scratching or transfer (that is, excellent in printing adhesion). The adhesive sheet disclosed herein is further preferably solvent-resistant to the extent that it does not significantly change the appearance of the printed image with an alcohol (e.g., ethanol) when the printing is corrected or eliminated.

The adhesive sheet disclosed herein can be implemented in addition to the resin layer, the adhesive layer, the adhesive layer, and the top coat layer, and further includes other layers. The arrangement of the "other layer" may be, for example, between the first surface (back surface) of the first resin layer and the top coat layer, between the second surface (front surface) of the second resin layer, and the adhesive layer. The layer disposed between the back surface of the first resin layer and the top coat layer may be, for example, a layer containing the antistatic component (the above top coat layer). The layer disposed between the front surface of the second resin layer and the adhesive layer may be, for example, an undercoat layer (an anchor layer), a top coat layer, or the like which improves the anchoring property of the adhesive layer to the second surface. An adhesive sheet in which a top coat layer is disposed on the front surface of the second resin layer, an anchor layer is disposed on the top coat layer, and an adhesive layer is disposed thereon may be used.

The optical member of the present invention is preferably protected by the above-mentioned adhesive sheet. Since the adhesive sheet is excellent in antistatic property or pick-up property, it can be used for surface protection applications (adhesive sheets) such as processing, transportation, and shipping, and is useful for protecting the surface of the optical member (polarizing plate or the like). In particular, it can be used for a plastic product or the like which is likely to generate static electricity. Therefore, it is very useful for antistatic use in the technical field related to optical and electronic parts where static electricity is a particularly serious problem.

In addition, the total thickness of the adhesive sheet of the present invention is preferably from 14 μm to 400 μm, more preferably It is 40 μm to 200 μm, preferably 55 μm to 100 μm. When it is in the above range, the adhesive properties (removability, adhesion, and the like), workability, and appearance characteristics are excellent, which is preferable. Furthermore, the above total thickness means a total of thicknesses including all layers of the resin layer, the adhesive layer, the adhesive layer, and the top coat layer.

[Examples]

Hereinafter, some embodiments related to the present invention will be described, but the present invention is not intended to be limited to the specific examples described above. Further, in the following description, "parts" and "%" are quality standards unless otherwise stated.

In addition, each characteristic in the following description is each measured or evaluated as follows.

<Measurement of Weight Average Molecular Weight (Mw)>

The weight average molecular weight (Mw) was measured using a GPC apparatus (HLC-8220GPC) manufactured by Tosoh Corporation. The measurement conditions are as follows.

Sample concentration: 0.2% by mass (THF solution)

Sample injection amount: 10μl

Dissolution: THF

Flow rate: 0.6ml/min

Measuring temperature: 40 ° C

Column:

Sample column; TSKguardcolumn SuperHZ-H (1) + TSKgel SuperHZM-H (2)

Reference column; TSKgel SuperH-RC (1 root)

Detector: Differential Refractometer (RI)

Further, the weight average molecular weight is determined by a value in terms of polystyrene. Further, when it is necessary to measure the number average molecular weight (Mn), it is also measured in the same manner as the weight average molecular weight.

<glass transition temperature (Tg)>

The glass transition temperature Tg (° C.) was determined by the following formula using the following literature values as the glass transition temperature Tgn (° C.) of the homopolymer of each monomer.

Formula: 1/(Tg+273)=Σ[Wn/(Tgn+273)] [wherein, Tg (°C) represents the glass transition temperature of the copolymer, and Wn(-) represents the weight fraction of each monomer, Tgn (°C) represents the glass transition temperature of the homopolymer of each monomer, and n represents the type of each monomer].

Literature value:

2-ethylhexyl acrylate (2EHA): -70 ° C

N-butyl acrylate (BA): -55 ° C

2-hydroxyethyl acrylate (HEA): -15 ° C

Acrylic acid (AA): 106 ° C

Methoxy polyethylene glycol monomethacrylate (PME-400): -60 ° C

In addition, as the literature value, refer to "The Synthetic, Design, and New Use Outlook of Acrylic Resin" (published by the Central Business Development Center Publishing Department) and the "Polymer Handbook" (John Wiley & Sons) and the monomer manufacturer catalogue value.

Further, the glass transition temperature (Tg) (°C) of the (meth)acrylic polymer obtained from a monomer having an unknown literature value is determined by dynamic viscoelasticity measurement in the following procedure.

First, a (meth)acrylic polymer sheet having a thickness of 20 μm was laminated to a thickness of about 2 mm, and the obtained object was punched out to have a diameter of 7.9 mm to prepare cylindrical particles as a sample for measuring glass transition temperature (Tg).

Using the sample for measurement described above, the measurement sample was fixed to a Φ7.9 mm parallel plate jig, and the temperature dependence of the loss elastic modulus G" was measured by a dynamic viscoelasticity measuring apparatus (ARES) manufactured by Rheometrics Co., Ltd., and the obtained G was obtained. "The temperature at which the curve reaches a maximum is taken as the glass transition temperature (Tg) (°C). The measurement conditions are as follows.

Determination: Shear mode

Temperature range: -70 ° C ~ 150 ° C

Heating rate: 5 ° C / min

Frequency: 1Hz

<Measurement of thickness>

The measurement was carried out using a digital micrometer (manufactured by Anritsu Corporation, product name "KC-351C").

<tensile strength>

The measurement was carried out in accordance with JIS C 2318 using a tensile tester (manufactured by Shimadzu Corporation, product name "Autograph").

<Storage elastic modulus of the adhesive layer>

The laminated layer was then brought to a thickness of about 2 mm, and the obtained object was punched out to be Φ7.9 mm, and cylindrical particles were prepared and used as samples for measurement. Using the sample for measurement described above, the measurement sample was fixed on a Φ7.9 mm parallel plate jig, and the storage elastic modulus G' at 23 ° C was measured using a dynamic viscoelasticity measuring apparatus (ARES) manufactured by Rheometrics Co., Ltd. The measurement conditions are as follows.

Determination: Shear mode

Frequency: 1Hz

The storage elastic modulus (23 ° C) as the adhesive layer in the present invention is 1.0 × 10 ⁴ Pa or more and less than 5.0 × 10 ⁷ Pa, preferably 1.0 × 10 ⁴ Pa or more and less than 1.0 × 10 ⁷ Pa. More preferably, it is 1.0 × 10 ⁵ Pa or more and less than 1.0 × 10 ⁶ Pa. If it is in the above range, the pick-up property of the adhesive sheet is good, which is a preferable aspect.

<Measurement of Surface Resistivity>

The measurement was carried out in accordance with JIS-K-6911 using a resistivity meter (manufactured by Mitsubishi Chemical Analytech, Hiresta UP MCP-HT450) under an atmosphere of a temperature of 23 ° C and a humidity of 50% RH.

Further, as the surface resistivity (Ω/□) in the present invention, it is preferable that it is initially and at room temperature (RT) (23 ° C × 50% RH) × 1 week (7 days). It is 1.0 × 10 ¹¹ , more preferably less than 5.0 × 10 ¹⁰ , and further preferably less than 1.5 × 10 ¹⁰ . The pressure-sensitive adhesive sheet which exhibits the surface resistivity in the above range can be suitably used, for example, as an adhesive sheet used in the processing or transportation process of a liquid-repellent article such as a liquid crystal cell or a semiconductor device.

<Measurement of peeling off electrostatic voltage (polarizing plate side)>

Each of the adhesive sheets 1 was cut into a size of 70 mm in width and 130 mm in length, and after peeling off the release liner, as shown in FIG. 2, it was bonded to the acrylic resin sheet 3 by manual roll bonding after pre-removal ( Made by Mitsubishi Rayon Co., Ltd., trade name "ACRYLITE", thickness: 1mm, width: 70mm, length: 100mm) on the surface of polarizing plate 2 (made by Nitto Denko Co., Ltd., SEG1423DU polarizing plate, width: 70mm, length: 100mm) The single end of the adhesive sheet 1 is protruded from the edge of the polarizing plate 2 by 30 mm.

The sample was allowed to stand in an environment of 23 ° C × 50% RH for 1 day, and then placed at a specific position of the sample fixing table 4 having a height of 20 mm. The end portion of the adhesive sheet 1 which protruded from the polarizing plate 2 by 30 mm was fixed to an automatic winder (not shown), and peeled off at a peeling angle of 150° and a peeling speed of 10 m/min. The potential of the surface of the adherend (polarizing plate) generated at this time was measured by the potential measuring device 5 (manufactured by Kasuga Electric Co., Ltd., model "KSD-0103"), which was fixed at a height of 100 mm from the center of the polarizing plate 2 as " The initial polarizer strips off the electrostatic voltage." The measurement was carried out in an environment of 23 ° C and 50% RH.

The peeling electrostatic voltage (kV) (absolute value) in the present invention is preferably 1 or less, more preferably 0.9 or less, still more preferably 0.5 or less. If it is within the above range, for example, damage to the liquid crystal driver can be prevented, which is preferable.

<Back adhesion (A) measurement>

As shown in Fig. 3, the adhesive sheet 1 of each example was cut into a size of 70 mm in width and 100 mm in length, and the adhesive sheet (the side on which the adhesive layer 20 was provided) 20A of the adhesive sheet 1 was coated with a double-sided adhesive tape 130. It is fixed on SUS304 stainless steel plate 132. A single-sided adhesive tape having an acrylic adhesive 162 (in the order of the first resin layer, the adhesive layer, and the second resin layer) 164 (manufactured by Nitto Denko Corporation, trade name "No. 31B", width) 19 Mm) 160 is cut to a length of 100 mm. The adhesive surface 162A of the adhesive tape 160 was pressure-bonded to the back surface of the adhesive sheet 1 (i.e., the surface of the top coat layer 14) 1A under the pressure of 0.25 MPa and a speed of 0.3 m/min. The obtained object was allowed to stand under the conditions of 23 ° C and 50% RH for 30 minutes. Then, the adhesive tape 160 was peeled off from the back surface 1A of the adhesive sheet 1 at a peeling speed of 0.3 m/min and a peeling angle of 180 degrees using a universal tensile tester, and the adhesive force at this time was measured (A) [N/ 19mm].

Further, the back surface adhesive force (A) is preferably 3.0 N/19 mm or more, more preferably 4.0 N/19 mm or more, still more preferably 5.0 N/19 mm or more, and most preferably 6.0 N/19 mm or more. If the adhesion is less than 3.0 N/19 mm, sufficient adhesion cannot be obtained, pickup property is deteriorated, and peeling workability of the protective film is lowered, which is not preferable.

<Measurement of adhesion to polarizing plate (B)>

A planar polarizing plate (TAC polarizing plate manufactured by Nitto Denko Corporation, SEG1425DU) having a width of 70 mm and a length of 100 mm was prepared as a adherend. The adhesive sheets of the respective examples were cut into a size of 25 mm in width and 100 mm in length, and the adhesive faces were crimped to the polarizing plate under the conditions of a pressure of 0.25 MPa and a speed of 0.3 m/min. After the obtained object was allowed to stand in an environment of 23 ° C and 50% RH for 30 minutes, the adhesive sheet was adhered to the above conditions under the same conditions using a universal tensile tester at a peeling speed of 0.3 m/min and a peeling angle of 180°. The polarizing plate was peeled off, and the adhesion (B) [N/25 mm] at this time was measured.

Further, the adhesive force (B) is preferably 4.5 N/25 mm or less, more preferably 4 N/25 mm or less, further preferably 3.5 N/25 mm or less, and most preferably 3 N/25 mm or less. If the above adhesive force exceeds 4.5 N/25 mm, peeling workability is inferior and it is not preferable.

<pickup>

As shown in FIG. 4, the adhesive sheet 1 of each example was cut into a size of 50 mm in width and 100 mm in length, and the adhesive surface of the adhesive sheet 1 (the side on which the adhesive layer 20 was provided) 20A was pressed at a pressure of 0.25 MPa. The speed of 0.3 m/min was crimped to a flat polarizing plate (TAC polarizing plate manufactured by Nitto Denko Corporation, SEG1425DU) 50.

The single-sided adhesive tape 60 (manufactured by Nitto Denko Corporation, trade name "No. 31B") was cut into a width of 19 mm and a length of 50 mm. The adhesive layer (adhesive surface) 62 of the adhesive tape 60 was pressed by hand to the center of the back surface of the adhesive sheet 1 having a width of 50 mm (i.e., the surface of the top coat layer 14) so that the end portion protruded by 30 mm. The obtained object was allowed to stand under conditions of 23 ° C and 50% RH for 10 seconds. Then, the single-sided adhesive tape 60 was peeled off by hand, and the peeling state (pickup property) of the adhesive sheet 1 was evaluated.

The evaluation criteria were evaluated as the case where the adhesive sheet was peelable, and the case where the adhesive sheet could not be peeled off and the adhesive sheet remained was evaluated as ×.

<Flexing amount>

As shown in Fig. 5, the adhesive sheet 1 of each example was cut into a size of 20 mm in width and 150 mm in length, and the No. 31B tape T manufactured by Nitto Denko Co., Ltd. was used so that the adhesive surface of the adhesive sheet 1 was directed outward. The part is fixed to the glass plate G. The height H1 of the center position of the adhesive sheet at this time was measured. Then, a load L of 4.8 g was placed at the center position, and the height H2 of the center position of the adhesive sheet at this time was measured. The amount of deflection [mm] was obtained from the following formula.

Flexing amount = H1-H2 [mm]

Further, the amount of deflection is preferably 30 mm or less, more preferably 25 mm or less, still more preferably 20 mm or less. When the amount of deflection exceeds 30 mm, the optical member to which the adhesive sheet is bonded is easily deflected during transportation, which is not preferable.

<Evaluation of Printing (Printing Adhesion)>

After printing on the surface of the top coat using an X stamper manufactured by Atomic Seal Co., Ltd. under the measurement environment of 23 ° C × 50% RH, the Cellotepa (registered trademark) manufactured by Michelin Co., Ltd. was attached from above the printed image, and then Peeling was carried out under the conditions of a peeling speed of 30 m/min and a peeling angle of 180°. Then, the surface after peeling was visually observed, and the case where 50% or more of the printing area was peeled off was evaluated as × (printing failure), and 50% or more of the printing area was not peeled off and remained as ○ (printing property was good) ).

Hereinafter, the top coat layer, the adhesive composition (adhesive solution), and the adhesive sheet (Table) will be described. Preparation method of face protective film).

[Example 1]

<Preparation of Resin Layer Film (Sequence of First Resin Layer, Adhesive Layer, and Second Resin Layer)>

100 parts by mass of butyl acrylate (BA), 5.0 parts by mass of acrylic acid (AA), and 0.075 parts by mass of 2-hydroxyethyl acrylate (2HEA), 2 in a reaction vessel equipped with a cooling tube, a nitrogen gas introduction tube, a thermometer, and a stirring device. 0.3 parts by mass of 2'-azobisisobutyronitrile and ethyl acetate were reacted at 60 ° C for 6 hours while stirring under a nitrogen gas stream to obtain an acrylic polymer solution having a weight average molecular weight of 1.63 million. To 100 parts by mass of the polymer solid content component of the acrylic polymer solution, 0.6 parts by mass of an isocyanate-based polyfunctional compound (trade name "Coronate L", manufactured by Nippon Polyurethane Co., Ltd.) and a decane coupling agent (Shin-Etsu Chemical Industry Co., Ltd.) were added. Manufactured, trade name: KBM403) 0.08 parts by mass to prepare an acrylic adhesive 1 composition solution.

The above-mentioned acrylic adhesive 1 composition solution was applied onto a polyester resin film (manufactured by Toyobo Co., Ltd., trade name: E5000, thickness: 38 μm, tensile strength: 208 MPa) as a resin layer, and heated at 90 ° C. Thereby, an adhesive layer having a thickness of 20 μm was formed. The storage elastic modulus at 23 ° C of the obtained subsequent layer was 1.0 × 10 ⁵ Pa.

Then, a polyester resin film (manufactured by Toyobo Co., Ltd., trade name: E5000, thickness: 38 μm, tensile strength: 208 MPa) was laminated on the adhesive layer to obtain a resin layer film having a thickness of 96 μm.

<Preparation of Acrylic Adhesive 1 Solution>

95 parts by mass of 2-ethylhexyl acrylate (2EHA) and 5 parts by mass of 2-hydroxyethyl acrylate (HEA) were placed in a four-necked flask equipped with a stirring blade, a thermometer, a nitrogen gas introduction tube, and a cooler as a polymerization initiation. 0.2 parts by mass of 2,2'-azobisisobutyronitrile and 150 parts by mass of ethyl acetate, nitrogen gas was introduced while stirring slowly, and the temperature of the liquid in the flask was maintained at around 65 ° C for 6 hours. A (meth)acrylic polymer solution (40% by mass) was prepared. The above acrylic polymer has a weight average molecular weight of 550,000, and the glass is turned The shift temperature (Tg) was -68 °C.

The (meth)acrylic polymer solution (40% by mass) was diluted to 20% by mass with ethyl acetate, and hexamethylene was added as a crosslinking agent in 500 parts by mass of the solution (100 parts by mass of the solid content). 4 parts by mass of the isocyanurate form of the diisocyanate (manufactured by Japan Polyurethane Industry Co., Ltd., trade name: Coronate HX (C/HX)) (solid content: 4 parts by mass), and dibutyltin dilaurate as a crosslinking catalyst ( 2 parts by mass of an ethyl acetate solution) 2 parts by mass (0.02 parts by mass of a solid content) was mixed and stirred to prepare an acrylic pressure-sensitive adhesive 1 solution.

<Preparation of Topcoat Solution (Topcoat 1)>

A polyester resin Vylonal MD-1480 (25% aqueous solution, manufactured by Toyobo Co., Ltd.) as a binder, polyaniline sulfonic acid (aqua-PASS, weight average molecular weight 40,000, manufactured by Mitsubishi Rayon Co., Ltd.) as a conductive polymer, As a crosslinking agent, an isocyanurate form of diisopropylamine-terminated hexamethylene diisocyanate, an oil amide as a lubricant is added to a mixed solvent of water/ethanol (1/3), and added 100 parts by mass of the binder of the solid content, 75 parts by mass of the conductive polymer based on the solid content, 10 parts by mass of the crosslinker based on the solid content, and 30 parts by mass of the solid content. The lubricant was thoroughly mixed by stirring for about 20 minutes. A solution for topcoat (face coat 1) of about 0.4% of NV was thus prepared.

<Preparation of resin layer film with top coat (sequence of top coat, first resin layer, adhesive layer and second resin layer)>

One surface of the above resin layer film was subjected to corona treatment, and the above surface coating solution was applied to the corona-treated surface so that the thickness after drying was 30 nm. The coated product was dried by heating at 130 ° C for 1 minute to prepare a resin layer film (the order of the top coat layer, the first resin layer, the adhesive layer and the second resin layer) having a top coat layer.

<Production of Adhesive Sheet (Surface Protective Film)>

Applying the above acrylic adhesive solution to the resin layer film of the above-mentioned top coat layer The surface of the coating layer, the first resin layer, the adhesive layer, and the second resin layer on the opposite side to the top coat layer was heated at 130 ° C for 1 minute to form an adhesive layer having a thickness of 20 μm. Then, the surface of the above-mentioned adhesive layer was bonded to a polyfluorene-treated surface of a polyethylene terephthalate film (thickness: 25 μm) which was subjected to polyfluorination treatment as a separator on one surface, thereby producing an adhesive sheet ( Surface protective film).

[Embodiment 8]

<Preparation of polyester adhesive solution>

The polycarbonate diol (manufactured by Kuraray Co., Ltd., trade name: PNOC-2000, hydroxyl value: 53.7 KOHmg/g) 140.0 mass was placed in a four-piece separable flask equipped with a stirring blade, a thermometer and a reaction by-product separation tube. , dimer diol (manufactured by Unikema Co., Ltd., trade name: PRIPOL-2033) 60 parts by mass, trimethylolpropane 9.8 parts by mass, azelaic acid 55.4 parts by mass, tetra-n-butyl titanate as a catalyst 0.1 part by mass, the liquid temperature in the flask was raised to 180 ° C while slowly stirring was started in the presence of a small amount of xylene as a solvent for discharging water as a by-product of the reaction, and maintained at this temperature. After a short period of time, separation of the water outflow was observed and it was confirmed that the reaction started. Then, polymerization was carried out for about 19 hours to obtain a polyester. The polyester had a number average molecular weight of 19,000 and a degree of dispersion of 3.9.

The above polyester was diluted to 30% by mass with a mixed solution (ethyl acetate/toluene=1/1: mass ratio), and 2.4 parts by mass of trimethylolpropane/hexamethylene group was added to 100 parts by mass of the solution. An isocyanate trimer adduct (manufactured by Nippon Polyurethane Industry Co., Ltd., trade name: Coronate H) was mixed and stirred to prepare a polyester-based pressure-sensitive adhesive composition (solution).

<Production of Adhesive Sheet (Surface Protective Film)>

Applying the polyester-based adhesive solution to the surface of the resin layer film (the top coat layer, the first resin layer, the adhesive layer, and the second resin layer) of the top coat layer opposite to the top coat layer, The film was heated at 130 ° C for 1 minute to form an adhesive layer having a thickness of 20 μm. Then, the surface of the above adhesive layer is bonded to the surface of the above-mentioned adhesive layer, and the poly(p-phenylene) which is treated as a separator by polyfluorination treatment A polyethylene oxide treatment surface of a polyethylene dicarboxylate film (thickness: 25 μm) was used to prepare an adhesive sheet (surface protective film).

[Embodiment 9]

<Preparation of urethane-based adhesive solution>

100 parts by mass of PREMINOL S3015 (manufactured by Asahi Glass Co., Ltd., Mn = 15000) as a polyol having three hydroxyl groups (OH groups) as a polyol, and trimethylolpropane/toluene diisocyanate as a polyfunctional isocyanate compound 13 parts by mass of a polymer adduct (manufactured by Japan Polyurethane Industry Co., Ltd., trade name: Coronate L), a catalyst (manufactured by Nippon Chemical Industry Co., Ltd., trade name: Nasem ferrous iron), 0.04 parts by mass, and acetic acid B as a dilute solution 210 parts by mass of the ester was stirred in a disperser to obtain a urethane-based adhesive composition (solution).

<Production of Adhesive Sheet (Surface Protective Film)>

Applying the above urethane-based adhesive solution to the resin layer film (the order of the top coat layer, the first resin layer, the adhesive layer, and the second resin layer) of the top coat layer is opposite to the top coat layer The surface was heated at 130 ° C for 1 minute to form an adhesive layer having a thickness of 20 μm. Then, a polyfluorene-treated surface of a polyethylene terephthalate film (thickness: 25 μm) which is a single-side polysilicon treatment as a separator is bonded to the surface of the above-mentioned pressure-sensitive adhesive layer to prepare an adhesive sheet (surface). Protective film).

[Comparative Example 1]

<Preparation of Solution for Topcoat (Topcoat 3)>

A polyester resin Vylonal MD-1480 (25% aqueous solution, manufactured by Toyobo Co., Ltd.) as a binder, 0.5% poly(3,4-ethylenedioxythiophene) (PEDOT) and 0.8% as a conductive polymer. An aqueous solution of polystyrene sulfonate (weight average molecular weight: 150,000) (PSS) (Baytron P, manufactured by HC Stark Co., Ltd.) was added to a mixed solvent of water/ethanol (1/1), and was added in an amount of 100 based on the solid content. a part by mass of the binder, 50 parts by mass of the conductive polymer based on the solid content, and 5 parts by mass of the melamine-based crosslinking agent, and stirred Mix thoroughly for about 20 minutes. A solution for topcoat (surface coat 3) of about 0.4% of NV was thus prepared.

[Comparative Example 3]

<Preparation of Topcoat Solution (Topcoat 5)>

It is prepared in a water-alcohol solvent, and contains an antistatic agent (manufactured by Konishi Co., Ltd., trade name "BONDEIP-P main agent") containing a cationic polymer in a mass ratio of 100:46.7 based on NV and as a hardener. A solution for topcoat (top coat 5) of epoxy resin (manufactured by Konishi Co., Ltd., trade name "BONDEIP-P hardener").

Corona treatment was performed on one surface of the resin layer film shown in Table 3, and the above-mentioned surface coating solution (top coat layer 5) was applied on the corona-treated surface so that the thickness after drying was 60 nm. It was dried by heating at 130 ° C for 1 minute to form a top coat. Then, a long-chain alkyl urethane-based release treatment agent (product of "One Oil & Fat Industry Co., Ltd., trade name "PEELOIL 1010") as a lubricant is applied to the surface of the top coat layer to make NV-based It was dried at 130 ° C for 1 minute at 40 ° C to form a two-layer top coat.

[Comparative Example 5]

<Preparation of Resin Layer Film (Sequence of First Resin Layer, Adhesive Layer, and Second Resin Layer)>

30 parts by mass of 2-ethylhexyl acrylate (2EHA), 70 parts by mass of methyl acrylate (MA), and 10 parts by mass of acrylic acid (AA) were placed in a reaction vessel equipped with a cooling tube, a nitrogen gas introduction tube, a thermometer, and a stirring device. 0.2 parts by mass of 2,2'-azobisisobutyronitrile and ethyl acetate were reacted at 60 ° C for 6 hours while stirring under a nitrogen gas stream to obtain an acrylic polymer solution having a weight average molecular weight of 1.1 million. To 100 parts by mass of the polymer solid content of the acrylic polymer solution, an epoxy compound (TETRAD-C, manufactured by Mitsubishi Gas Chemical Co., Ltd.) was added in an amount of 1.0 part by mass, and a urethane acrylate compound [Nippon Synthetic Chemical Industry] Manufactured by the company, UV-1700B] 40 parts by mass, acrylate compound [manufactured by Nippon Kayaku Co., Ltd., KAYARAD DPCA-120] 40 parts by mass, 1-hydroxycyclohexylphenyl A ketone (trade name: IRGACURE 184) [manufactured by Ciba Specialty Chemicals Co., Ltd.] was used in an amount of 7 parts by mass to prepare an acrylic adhesive 2 composition solution.

The above-mentioned acrylic adhesive 2 composition solution was applied to a polyester resin film (manufactured by Toyobo Co., Ltd., trade name: E5000, thickness: 38 μm, tensile strength: 208 MPa) as a resin layer, and heated at 90 ° C. Thus, an adhesive layer having a thickness of 12 μm was formed.

Then, a polyester resin film (manufactured by Toyobo Co., Ltd., trade name: E5000, thickness: 38 μm, tensile strength: 208 MPa) was laminated on the adhesive layer, and ultraviolet rays were irradiated with a cumulative light amount of 0.5 J/cm ² using a high pressure mercury lamp to form an adhesive layer. It was hardened to obtain a resin layer film having a thickness of 88 μm. The storage elastic modulus at 23 ° C of the obtained subsequent layer was 6.7 × 10 ⁷ Pa.

[Examples 2 to 10 and Comparative Examples 1 to 5]

An adhesive sheet (surface protective film) was produced in the same manner as in Example 1 based on the contents of the preparations in Tables 1 and 2. Further, other additives which are not formulated in the embodiment 1 (for example, an antistatic component formulated in the preparation of the adhesive solution, etc.) are formulated at the time of preparation of the adhesive solution. Further, in Comparative Example 4, only the second resin layer shown in Table 4 was used instead of the resin layer film. The blending amounts in Tables 1 and 2 represent solid components.

The various measurements and evaluations described above were carried out for the adhesive sheets of the examples and the comparative examples. The results are shown in Tables 3 and 4.

In addition, the abbreviations in Table 1 and Table 2 are explained as follows.

2EHA: 2-ethylhexyl acrylate

BA: n-butyl acrylate

HEA: 2-hydroxyethyl acrylate

AA: Acrylic

PME-400: methoxypolyethylene glycol monomethacrylate

C/HX: isocyanurate form of hexamethylene diisocyanate (manufactured by Japan Polyurethane Co., Ltd., trade name: Coronate HX)

D201: hexamethylene diisocyanate bifunctional isocyanate (manufactured by Asahi Kasei Corporation, trade name: Duranat D-201)

C/L: Trimethylolpropane/toluene diisocyanate trimer adduct (manufactured by Japan Polyurethane Co., Ltd., trade name: Coronate L)

MT: 4,4'-diphenylmethane diisocyanate (manufactured by Japan Polyurethane Co., Ltd., trade name: Millionate MT)

BMP: 1-butyl-3-methylpyridinium bis(trifluoromethanesulfonyl) quinone imine (ionic liquid, liquid at 25 ° C, Wako Pure Chemical Co., Ltd.)

Polyethylene naphthalate resin 12μm: (manufactured by Teijin DuPont, trade name: Teonex Q51, tensile strength: 311MPa)

Polyethylene naphthalate resin 50 μm: (manufactured by Teijin DuPont, trade name: Teonex Q51, tensile strength: 272 MPa)

Polyester resin 38 μm: (manufactured by Toyobo Co., Ltd., trade name: E5000, tensile strength: 208 MPa)

Polyester resin 75 μm: (manufactured by Toyobo Co., Ltd., trade name: E5000, tensile strength: 188 MPa)

Polycarbonate resin 65 μm: (manufactured by Kaneka Co., Ltd., trade name: ELMECH, tensile strength: 105 MPa)

From the above evaluation results, it was confirmed that in all the examples, by using an adhesive sheet having a desired thickness ratio, a storage elastic modulus of an adhesive layer, an adhesive layer, a top coat layer, or the like, antistatic property and adhesion were observed. Excellent in characteristics, pick-up, deflection, and printing adhesion. On the other hand, in the comparative example, the desired adhesive sheet having a desired thickness ratio, or an adhesive layer, a top coat layer or the like was not used, and thus all of the characteristics were not obtained.

[Industrial availability]

The adhesive sheet disclosed herein is suitable for use as an optical member used as a constituent element of a liquid crystal display panel, a plasma display panel (PDP), an organic electroluminescence (EL) display, or a touch panel display, and the like. An adhesive sheet (surface protective film) for protecting an optical member. In particular, it is an adhesive sheet (optical sheet) for optical members such as a polarizing plate (polarizing film) for a liquid crystal display panel, a wavelength plate, a phase difference plate, an optical compensation film, a brightness enhancement film, a light diffusion sheet, and a reflection sheet. It is useful to use adhesive sheets.

1‧‧‧Adhesive sheet (surface protective film)

6‧‧‧First resin layer

7‧‧‧Next layer

8‧‧‧Second resin layer

14‧‧‧Face coating

20‧‧‧Adhesive layer

Claims (6)

An adhesive sheet characterized by having a first resin layer, an adhesive layer, a second resin layer and an adhesive layer formed of an adhesive composition, the thickness of the adhesive layer being opposite to the thickness of the first resin layer The ratio of the sum of the thicknesses of the second resin layers is 0.50 or less, and the storage elastic modulus at 23 ° C of the adhesive layer is 1.0 × 10 ⁴ Pa or more and less than 5.0 × 10 ⁷ Pa, and the first resin layer is a surface coating layer on a surface opposite to the surface having the above-mentioned adhesive layer, the top coating layer comprising a polyaniline sulfonic acid as a conductive polymer component, a polyester resin as a binder component, and a crosslinking agent The composition for topcoat of an isocyanate type compound is formed. The adhesive sheet according to claim 1, wherein the top coat composition further contains a fatty guanamine as a lubricant. The adhesive sheet of claim 1, wherein at least one of the above resin layers is a polyester film. The adhesive sheet according to claim 1, wherein the adhesive composition contains at least one selected from the group consisting of an acrylic adhesive, an urethane adhesive, and a polyester adhesive. The adhesive sheet according to any one of claims 1 to 4, wherein the above adhesive composition contains an antistatic component. An optical member characterized in that it is protected by an adhesive sheet according to any one of claims 1 to 5.