TW202031857A - Adhesive film, foldable device, and rollable device - Google Patents

Abstract

Provided is an adhesive film having excellent bendability and transparency. Also provided are a foldable device and a rollable device having excellent bendability. This adhesive film has a substrate layer and an adhesive layer, tan [delta](0.7%) at a strain of 0.7% of the adhesive film measured in the tension mode of a viscoelasticity measurement device being 0.1 or less. This adhesive film has a substrate layer and an adhesive layer, the difference (tan [delta](0.7%) - tan [delta](0.1%)) between tan [delta](0.7%) at a strain of 0.7% and tan [delta](0.1%) at a strain of 0.1% of the adhesive film measured in the tension mode of a viscoelasticity measurement device being 0.05 or less.

Description

Adhesive film, foldable device, and rollable device

The present invention relates to an adhesive film. The present invention also relates to a foldable device with such an adhesive film and a rollable device with such an adhesive film.

Adhesive film is used for reinforcement or surface protection of various shapes of components.

For example, when a semiconductor device substrate (such as a TFT (thin-film transistor, thin-film transistor) substrate, etc.) is bonded to an integrated circuit (IC) or a flexible printed circuit board (FPC), it is usually anisotropically conductive Film (ACF) for thermocompression bonding. When performing such thermocompression bonding, an adhesive film may be bonded and reinforced in advance on the back side of the substrate of the semiconductor element (for example, Patent Document 1).

In addition, as a method for manufacturing flexible devices or rollable devices that has been continuously developed in recent years, generally, a release layer and a flexible or rollable film substrate are formed on a supporting substrate such as glass, and a TFT substrate is formed on the film substrate, and then An organic EL (Electroluminescence) layer is formed thereon. In addition, the support substrate is peeled off to produce a flexible device or a rollable device, but the flexible display layer or rollable display layer is very thin, so an abnormality occurs in the device due to operations and the like. Therefore, an adhesive film may be attached to the back side in advance for reinforcement (for example, Patent Document 2).

The substrate or the flexible device or the rollable device of the semiconductor device may be repeatedly bent. If the bending property of the adhesive film attached to the back side of the substrate is poor, the repetitiveness after bending will be deteriorated, or the worst will be due to repeated bending And the situation of fracture. Specifically, if an adhesive film is to be attached to a bending part (for example, a movable bending part of a folding member, etc.), the following problems arise, for example.

When the adhesive film is bent at an angle, the inner diameter side of the bending is subjected to a compressive force, so in order to relax the force, the adhesive film itself deforms. Specifically, for example, wrinkles are likely to occur.

When the adhesive film is bent at an angle, the outer diameter side of the bending is subjected to tensile stress. Therefore, when the stress is relieved, a bulge from the adherend occurs.

When the adhesive film is bent at an angle, the thickness of the bent or stretched part of the adhesive film changes greatly, and it is also prone to wrinkles or bulges in this state. For example, when the adhesive film is stretched, the thickness of the adhesive film is greatly reduced, prone to bulge from the adherend.

In this way, in the previous adhesive film, the unevenness of the diagonal part or the curved part cannot be fully followed.

In particular, when the movable bending portion is attached to the adhesive film, the movable bending portion is repeatedly bent, so that the movable bending portion is in a state where a bend mark (so-called "crease") is attached to the adhesive film.

In addition, when thermocompression bonding is performed to bond an integrated circuit (IC) or a flexible printed circuit board (FPC) to a substrate (such as a TFT substrate) of a semiconductor element, the bonding position is confirmed from the back side of the substrate and pressure bonding is performed. Therefore, the adhesive film attached to the back side of the substrate is required to have transparency. Prior art literature Patent literature

Patent Document 1: Japanese Patent No. 5600039 Patent Document 2: Japanese Patent No. 6376271

[The problem to be solved by the invention]

The subject of the present invention is to provide an adhesive film excellent in flexibility and transparency. The subject of the present invention is to provide a foldable device and a rollable device with excellent flexibility. [Technical means to solve the problem]

The adhesive film of the present invention is an adhesive film having a substrate layer and an adhesive layer, and The tanδ (0.7%) at a strain of 0.7% measured in the tensile mode of the viscoelasticity measuring device is 0.1 or less.

The adhesive film of the present invention is an adhesive film having a substrate layer and an adhesive layer, and The difference between tanδ (0.7%) at a strain of 0.7% and tanδ (0.1%) at a strain of 0.1% (tanδ(0.7%)－tanδ(0.1%)) measured in the tensile mode of the viscoelasticity measuring device is 0.05 the following.

彎曲且於90℃下保持48小時後，解除該彎曲，於23℃、50%RH下放置24小時後之彎曲角度為60度～180度。In one embodiment, the adhesive film of the present invention has 6

After bending and keeping it at 90°C for 48 hours, the bending is released, and the bending angle after being left at 23°C and 50%RH for 24 hours is 60 degrees to 180 degrees.

In one embodiment, the adhesive film of the present invention has a top coat on the surface of the substrate layer opposite to the surface having the adhesive layer.

In one embodiment, the top coat layer contains a binder containing at least one selected from polyester resins and urethane resins.

In one embodiment, the adhesive includes a urethane-based resin.

In one embodiment, the top coat layer contains an antistatic component.

In one embodiment, the Young's modulus at 23° C. of the substrate layer is 6.0×10 ⁷ Pa or more.

In one embodiment, the material of the substrate layer is at least one selected from polyimide and polyether ether ketone.

In one embodiment, the adhesive film of the present invention has a top coat on the surface of the substrate layer opposite to the surface with the adhesive layer, and the top coat contains an adhesive containing a urethane-based resin And antistatic components, the material of the substrate layer is at least one selected from polyimide and polyether ether ketone.

In one embodiment, the total light transmittance of the adhesive film of the present invention is 20% or more.

In one embodiment, the haze of the adhesive film of the present invention is 15% or less.

In one embodiment, the stretching speed of the adhesive layer at 23° C. is 300 mm/min, and the adhesive force to the SUS (stainless steel) plate under 180° peeling is 1 N/25 mm or more.

In one embodiment, the adhesive layer contains an acrylic adhesive.

In one embodiment, the adhesive film of the present invention is attached to a foldable member.

In one embodiment, the above-mentioned foldable member is an OLED (Organic Light-Emitting Diode).

In one embodiment, the adhesive film of the present invention is attached to a rollable member.

In one embodiment, the above-mentioned rollable member is an OLED.

The foldable device of the present invention includes the above-mentioned adhesive film.

The rollable device of the present invention includes the above-mentioned adhesive film. [Effects of Invention]

According to the present invention, an adhesive film excellent in flexibility and transparency can be provided. According to the present invention, it is possible to provide a foldable device and a rollable device with excellent flexibility.

≪≪Adhesive film≫≫ The adhesive film of the present invention has a substrate layer and an adhesive layer. That is, as long as the adhesive film of the present invention has a base layer and an adhesive layer, it can have any suitable other layer within a range that does not impair the effects of the present invention.

The substrate layer may be one layer, or two or more layers. In terms of further expressing the effects of the present invention, the substrate layer is preferably one layer.

The adhesive layer may be one layer, or two or more layers. In terms of further expressing the effects of the present invention, the adhesive layer is preferably one layer.

The adhesive film of the present invention can be provided with any suitable release liner for the purpose of protection until use, etc., on the surface opposite to the base layer of the adhesive layer.

As a release liner, for example, a release liner that has been treated with silicone on the surface of a substrate (liner substrate) such as paper or plastic film, and a substrate (liner substrate) such as paper or plastic film The surface is laminated with polyolefin resin and release liner. As for the plastic film used as the backing substrate, for example, polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, vinyl chloride copolymer film can be cited , Polyethylene terephthalate film, polybutylene terephthalate film, polyurethane film, ethylene-vinyl acetate copolymer film, etc.

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

The total thickness d of the adhesive film of the present invention is preferably 1 μm to 500 μm, more preferably 5 μm to 200 μm, further preferably 10 μm to 150 μm, particularly preferably 20 μm to 100 μm, most preferably 30 μm μm～80 μm. If the total thickness d of the adhesive film of the present invention is within the above range, the effects of the present invention can be further exhibited.

The tanδ (0.7%) of the adhesive film of the present invention measured in the tensile mode of the viscoelasticity measuring device at 0.7% is 0.1 or less, preferably 0.09 or less, more preferably 0.08 or less, and still more preferably 0.07 or less , Particularly preferably below 0.06. If the tanδ (0.7%) of the adhesive film of the present invention measured in the tensile mode of the viscoelasticity measuring device is within the above range, the effect of the present invention can be further expressed.

The tanδ (0.7%) of the adhesive film at a strain of 0.7% measured in the tensile mode of the viscoelasticity measuring device is an indicator of the loss tangent when the adhesive film is greatly bent. Based on various experimental data, it is found that if the value is within the above range, the effect of the present invention can be further demonstrated until the present invention is completed. The method for measuring tanδ (0.7%) at a strain of 0.7% measured in the tensile mode of the viscoelasticity measuring device is described in detail below.

The tanδ (0.1%) of the adhesive film of the present invention measured in the tensile mode of the viscoelasticity measuring device at a strain of 0.1% is preferably 0.1 or less, more preferably 0.08 or less, further preferably 0.06 or less, and particularly preferably Below 0.05. If the tanδ (0.1%) of the adhesive film of the present invention measured in the tensile mode of the viscoelasticity measuring device is within the above range, the effect of the present invention can be further expressed.

The tanδ (0.1%) of the adhesive film measured in the tensile mode of the viscoelasticity measuring device at a strain of 0.1% is an indicator of the loss tangent when the adhesive film is slightly bent. Based on various experimental data, it is found that if the value is within the above range, the effect of the present invention can be further demonstrated until the present invention is completed. The method for measuring tanδ (0.1%) at a strain of 0.1% measured in the tensile mode of the viscoelasticity measuring device is detailed below.

The difference between the tanδ (0.7%) at a strain of 0.7% (0.7%) and the tanδ (0.1%) at a strain of 0.1% (tanδ(0.7%)-tanδ() of the adhesive film of the present invention measured in the tensile mode of the viscoelasticity measuring device 0.1%)) is preferably 0.05 or less, more preferably 0.04 or less, and still more preferably 0.03 or less. If the adhesive film of the present invention is measured in the tensile mode of the viscoelasticity measuring device, the difference between tanδ (0.7%) at a strain of 0.7% and tanδ (0.1%) at a strain of 0.1% (tanδ(0.7%)-tanδ (0.1%)) within the above range, the effect of the present invention can be further expressed.

The difference between the tanδ (0.7%) at a strain of 0.7% and the tanδ (0.1%) at a strain of 0.1% (tanδ(0.7%)－tanδ(0.1%) of the adhesive film measured in the tensile mode of the viscoelasticity measuring device ) Is an index indicating the difference between the loss tangent when the adhesive film is bent greatly and the loss tangent when the adhesive film is bent slightly. Based on various experimental data, it is found that if the value is within the above range, the effect of the present invention can be further demonstrated until the present invention is completed.

彎曲且於90℃下保持48小時後，解除該彎曲，於23℃、50%RH下放置24小時後之彎曲角度較佳為60度～180度，更佳為80度～180度，進而較佳為100度～180度，尤佳為120度～180度，最佳為150度～180度。若本發明之黏著膜之以6

彎曲且於90℃下保持48小時後，解除該彎曲，於23℃、50%RH下放置24小時後之彎曲角度為上述範圍內，則可進一步表現本發明之效果。The adhesive film of the present invention is 6

After being bent and kept at 90°C for 48 hours, the bending is released. The bending angle after being placed at 23°C and 50%RH for 24 hours is preferably 60 degrees to 180 degrees, more preferably 80 degrees to 180 degrees, and more It is preferably 100 degrees to 180 degrees, particularly preferably 120 degrees to 180 degrees, and most preferably 150 degrees to 180 degrees. If the adhesive film of the present invention is 6

After bending and keeping at 90°C for 48 hours, the bending is released, and the bending angle after being left at 23°C and 50%RH for 24 hours is within the above range, the effect of the present invention can be further exhibited.

彎曲且於90℃下保持48小時後，解除該彎曲，於23℃、50%RH下放置24小時後之彎曲角度係表示彎曲後之回覆性之指標。有關以6

彎曲且於90℃下保持48小時後，解除該彎曲，於23℃、50%RH下放置24小時後之彎曲角度之測定方法，於下文中詳述。Adhesive film 6

After bending and keeping it at 90°C for 48 hours, the bending is released, and the bending angle after being left at 23°C and 50%RH for 24 hours is an indicator of the responsiveness after bending. About 6

After bending and keeping at 90°C for 48 hours, the bending is released, and the method of measuring the bending angle after being placed at 23°C and 50%RH for 24 hours is described in detail below.

The total light transmittance of the adhesive film of the present invention is preferably 20% or more, more preferably 30% or more, still more preferably 40% or more, particularly preferably 50% or more, and most preferably 60% or more. If the total light transmittance of the adhesive film of the present invention is within the above-mentioned range, it can further exhibit excellent transparency.

The haze of the adhesive film of the present invention is preferably 15% or less, more preferably 13% or less, still more preferably 10% or less, particularly preferably 8% or less, and most preferably 6% or less. If the haze of the adhesive film of the present invention is within the above range, it can further exhibit excellent transparency.

The adhesive film of the present invention has excellent flexibility and transparency, so it is preferably attached to a foldable member. As the foldable member, any suitable member can be used as long as it is a member that can be repeatedly bent. As such a foldable member, for example, a foldable optical member, a foldable electronic member, etc. can be cited, and a foldable OLED can be representatively cited.

The adhesive film of the present invention has excellent flexibility and transparency, so it is preferably attached to a rollable member. As the rollable member, any suitable member can be used as long as it is a member that can be repeatedly wound and rewinded. As such a rollable member, for example, a rollable optical member, a rollable electronic component, etc., and a rollable OLED can be mentioned representatively.

≪Substrate layer≫ The thickness of the substrate layer is preferably 1 μm to 500 μm, more preferably 5 μm to 300 μm, still more preferably 10 μm to 100 μm, particularly preferably 15 μm to 80 μm, most preferably 20 μm to 60 μm . If the thickness of the substrate layer is within the above range, the effect of the present invention can be further exhibited.

The Young's modulus of the substrate layer at 23°C is preferably 6.0×10 ⁷ Pa or more, more preferably 1.0×10 ⁸ Pa or more, still more preferably 5.0×10 ⁸ Pa or more, and particularly preferably 8.0×10 ⁸ Pa or more, preferably 1.0×10 ⁹ Pa or more. The upper limit of the Young's modulus at 23°C of the substrate layer is typically 1.0×10 ¹¹ Pa or less. If the Young's modulus at 23°C of the substrate layer is within the above range, the effect of the present invention can be further exhibited. If the Young's modulus at 23°C of the substrate layer is too low, if the adhesive film is bent at an angle, there is a risk that the compression on the inner diameter side and the stretching on the outer diameter side may not be sufficiently maintained, and the thickness is easy Changes are likely to occur from the uplift of the adherend. If the Young's modulus at 23°C of the base layer is too high, there is a possibility that the adhesive film cannot be easily deformed. The method of measuring Young's modulus is detailed below.

As the material of the substrate layer, any suitable material can be used within a range that does not impair the effects of the present invention. As a material of such a base material layer, a resin material can be mentioned typically.

As for the resin material as the material of the substrate layer, for example, polyimide (PI), polyether ether ketone (PEEK), polyethylene terephthalate (PET), polyethylene naphthalate can be cited. (PEN), polybutylene terephthalate (PBT), polymethyl methacrylate (PMMA) and other acrylic resins, polycarbonate, triacetate cellulose (TAC), polyvinyl, polyarylate, Polyethylene (PE), polypropylene (PP), ethylene-propylene copolymer, ethylene-vinyl acetate copolymer (EVA), polyamide (nylon), wholly aromatic polyamide (aramid), polyvinyl chloride ( PVC), polyvinyl acetate, polyphenylene sulfide (PPS), fluorine resin, cyclic olefin polymer, etc.

As for the resin material used as the material of the substrate layer, in terms of further exhibiting the effects of the present invention, preferably selected from polyimide (PI), polyether ether ketone (PEEK), cyclic olefin series At least one polymer, more preferably at least one selected from polyimide (PI) and polyether ether ketone (PEEK).

≪Adhesive layer≫ The thickness of the adhesive layer is preferably 1 μm to 500 μm, more preferably 5 μm to 300 μm, still more preferably 10 μm to 100 μm, particularly preferably 15 μm to 80 μm, most preferably 20 μm to 60 μm . If the thickness of the adhesive layer is within the above range, the effect of the present invention can be further expressed.

The tensile speed of the adhesive layer at 23°C is 300 mm/min, and the adhesion to the glass plate under 180° peeling is preferably 1 N/25 mm or more, more preferably 5 N/25 mm or more, and more preferably 10 N/25 mm or more, more preferably 12 N/25 mm or more, and most preferably 15 N/25 mm or more. The tensile speed of the adhesive layer at 23°C is 300 mm/min, and the upper limit of the adhesion to the glass plate under 180° peeling is representative, preferably 1000 N/25 mm or less, more preferably 5000 N/ 25 mm or less, more preferably 300 N/25 mm or less, particularly preferably 200 N/25 mm or less, and most preferably 100 N/25 mm or less. If the stretching speed of the adhesive layer at 23°C is 300 mm/min and the adhesion to the glass plate under 180° peeling is within the above range, the effect of the present invention can be further expressed.

The adhesive layer contains a base polymer. There may be only one type of base polymer, or two or more types. As the content ratio of the base polymer in the adhesive layer, in terms of further expressing the effect of the present invention, it is preferably 20% by weight to 100% by weight, more preferably 30% by weight to 95% by weight, and more It is preferably 40% by weight to 90% by weight, particularly preferably 45% to 85% by weight, and most preferably 50% to 80% by weight.

As the base polymer, any suitable polymer can be used within a range that does not impair the effects of the present invention. In terms of further expressing the effects of the present invention, the base polymer is preferably selected from acrylic polymers, rubber polymers, silicone polymers, and urethane polymers. At least one. That is, the adhesive layer preferably contains acrylic adhesives selected from the group consisting of acrylic adhesives containing acrylic polymers, rubber adhesives containing rubber polymers, silicone adhesives containing silicone polymers, and amines. At least one of the urethane-based adhesives of the carbamate-based polymer. In terms of further expressing the effect of the present invention, the adhesive layer preferably contains an acrylic adhesive. Hereinafter, the acrylic adhesive will be described in detail as a representative example of the adhesive that can be contained in the adhesive layer.

＜Acrylic adhesives＞ The acrylic adhesive contains an acrylic polymer as a base polymer. The acrylic adhesive may contain an adhesion imparting resin. The acrylic adhesive may contain a crosslinking agent.

When the acrylic adhesive contains acrylic polymer, adhesion-imparting resin and cross-linking agent, the content ratio of the total amount of acrylic polymer, adhesion-imparting resin and cross-linking agent to the total amount of acrylic adhesive In terms of further expressing the effect of the present invention, it is preferably 95% by weight or more, more preferably 97% by weight or more, and still more preferably 99% by weight or more.

(Acrylic polymer) As the acrylic polymer, for example, it is preferable to contain (meth)acrylic acid alkyl ester as a main monomer, and may further contain a monomer component of a secondary monomer having copolymerization with the main monomer. The so-called main unit system here refers to a component that accounts for more than 50% by weight of the entire monomer component.

As the alkyl (meth)acrylate, for example, a compound represented by the following formula (1) can be preferably used. CH ₂ =C(R ¹ )COOR ² (1)

Here, R ¹ in the above formula (1) is a hydrogen atom or a methyl group, and R ² is a chain alkyl group having 1 to 20 carbon atoms (hereinafter, the range of such carbon number may be expressed as "C1 -20"). From the viewpoint of the storage modulus of the adhesive layer, R ^{2 is} preferably a C1-14 chain alkyl group, more preferably a C2-10 chain alkyl group, and more preferably a C4-8 chain alkyl group. base. The term “chain-like” here refers to the meaning including straight-chain and branched-chain.

Examples of alkyl (meth)acrylates in which R ² is a C1-20 chain alkyl group include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, Isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, second butyl (meth)acrylate, amyl (meth)acrylate, (meth)acrylic acid Isoamyl ester, hexyl (meth)acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, ( Nonyl meth)acrylate, isononyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, undecyl (meth)acrylate, laurel (meth)acrylate Ester, tridecyl (meth)acrylate, tetradecyl (meth)acrylate, pentadecyl (meth)acrylate, cetyl (meth)acrylate, (meth) Heptadecyl acrylate, stearyl (meth)acrylate, isostearyl (meth)acrylate, nonadecyl (meth)acrylate, eicosyl (meth)acrylate, etc. . These alkyl (meth)acrylates may be only one type or two or more types.

As the alkyl (meth)acrylate, in terms of further expressing the effect of the present invention, preferably, n-butyl acrylate (BA) and 2-ethylhexyl acrylate (2EHA) are cited.

The content ratio of the alkyl (meth)acrylate in all the monomer components used in the synthesis of the acrylic polymer is preferably 70% by weight in terms of further expressing the effects of the present invention Above, it is more preferably 85% by weight or more, and still more preferably 90% by weight or more. The upper limit of the content ratio of the alkyl (meth)acrylate is preferably 99.5% by weight or less, more preferably 99% by weight or less. However, the acrylic polymer may be obtained by substantially polymerizing only alkyl (meth)acrylate.

When R ² is an alkyl group using the (meth) acrylic acid alkyl ester of the chain case of C4-8, as a monomer component contained in the (meth) acrylic acid alkyl ester of R ² is C4-8 The ratio of the alkyl (meth)acrylate of the chain alkyl group is preferably 50% by weight or more, more preferably 70% by weight or more, and still more preferably 90% by weight or more, more preferably 95% by weight or more, most preferably 99% by weight to 100% by weight.

As an embodiment of the acrylic polymer, an acrylic polymer in which 50% by weight or more of all monomer components is n-butyl acrylate (BA) can be mentioned. In this case, the content ratio of n-butyl acrylate (BA) in all monomer components is preferably more than 50% by weight and 100% by weight or less in terms of further expressing the effects of the present invention, and more It is preferably 55% to 95% by weight, more preferably 60% to 90% by weight, particularly preferably 63% to 85% by weight, most preferably 65% to 80% by weight. All monomer components may be less than the ratio of n-butyl acrylate (BA) and further contain 2-ethylhexyl acrylate (2EHA).

As an embodiment of the acrylic polymer, an acrylic polymer in which less than 50% by weight of all monomer components is 2-ethylhexyl acrylate (2EHA) can be cited. In this case, the content ratio of 2-ethylhexyl acrylate (2EHA) in all monomer components is preferably more than 0% by weight and 48% by weight in terms of further expressing the effects of the present invention Hereinafter, it is more preferably 5% to 45% by weight, still more preferably 10% to 43% by weight, particularly preferably 15% to 40% by weight, and most preferably 20% to 35% by weight. All monomer components may further contain n-butyl acrylate (BA) in a ratio greater than 2-ethylhexyl acrylate (2EHA).

It is possible to copolymerize other monomers in the acrylic polymer within a range that does not impair the effects of the present invention. Other monomers can be used, for example, for the purpose of adjusting the glass transition temperature (Tg) of the acrylic polymer and adjusting the adhesion performance. For example, as a monomer that can improve the cohesive force or heat resistance of the adhesive, sulfonic acid group-containing monomers, phosphoric acid group-containing monomers, cyano group-containing monomers, vinyl esters, and aromatic vinyl The compound etc. are preferably vinyl esters. Specific examples of vinyl esters include, for example, vinyl acetate (VAc), vinyl propionate, vinyl laurate, etc., and vinyl acetate (VAc) is preferred.

The "other monomers" may be only one type or two or more types. The content ratio of other monomers in all monomer components is preferably 0.001% to 40% by weight, more preferably 0.01% to 40% by weight, still more preferably 0.1% to 10% by weight, and particularly preferably 0.5 Weight% to 5% by weight, preferably 1% to 3% by weight.

Examples of other monomers that can be introduced into the acrylic polymer that can become a cross-linking point or can help improve adhesion include: hydroxyl (OH group)-containing monomers, carboxyl group-containing monomers, Acid anhydride group-containing monomers, amide group-containing monomers, amine group-containing monomers, amide group-containing monomers, epoxy group-containing monomers, (meth)acrylic acid group 𠰌line, ethylene Ethers, etc.

As an embodiment of the acrylic polymer, an acrylic polymer obtained by copolymerizing a carboxyl group-containing monomer as another monomer can be cited. Examples of carboxyl group-containing monomers include acrylic acid (AA), methacrylic acid (MAA), carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, and maleic acid. , Fumaric acid, crotonic acid, methacrylate, etc. Among them, in terms of further expressing the effect of the present invention, the carboxyl group-containing monomer preferably includes acrylic acid (AA) and methacrylic acid (MAA), and more preferably acrylic acid (AA).

When a carboxyl group-containing monomer is used as the other monomer, the content ratio of the other monomer in the total monomer components is preferably 0.1% by weight to 10% in terms of further expressing the effects of the present invention. % By weight, more preferably 0.2% by weight to 8% by weight, still more preferably 0.5% by weight to 5% by weight, particularly preferably 0.7% by weight to 4% by weight, most preferably 1% by weight to 3% by weight.

As an embodiment of the acrylic polymer, an acrylic polymer obtained by copolymerizing a hydroxyl-containing monomer as another monomer can be cited. Examples of hydroxyl-containing monomers include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, and (meth)acrylic acid 2 -Hydroxyalkyl (meth)acrylates such as hydroxybutyl, 4-hydroxybutyl(meth)acrylate, etc.; polypropylene glycol mono(meth)acrylate; N-hydroxyethyl(meth)acrylamide, etc. Among these, as a hydroxyl group-containing monomer, in terms of further expressing the effects of the present invention, preferably, the alkyl group is a linear (meth)acrylic hydroxyalkyl group having 2 to 4 carbon atoms. Specific examples of the base ester include 2-hydroxyethyl acrylate (HEA) and 4-hydroxybutyl acrylate (4HBA), and more preferably 4-hydroxybutyl acrylate (4HBA).

When a hydroxyl-containing monomer is used as the other monomer, the content ratio of the other monomer in the total monomer components is preferably 0.001% by weight to 10 in terms of further expressing the effect of the present invention. The weight% is more preferably 0.01% to 5% by weight, still more preferably 0.02% to 2% by weight, particularly preferably 0.03% to 1% by weight, most preferably 0.05% to 0.5% by weight.

As the Tg of the base polymer, in terms of further expressing the effects of the present invention, for example, it may be -80°C or higher. For the base polymer (preferably an acrylic polymer), from the viewpoint of improving the deformability of the adhesive layer in the shear direction, it is designed so that the Tg is preferably -15°C or less. In some embodiments, the Tg of the base polymer is, for example, preferably -25°C or lower, more preferably -40°C or lower, and still more preferably -50°C or lower. As the Tg of the base polymer, from the viewpoint of improving the cohesiveness or shape reversibility, for example, the Tg is preferably -70°C or higher (more preferably -65°C or higher, and still more preferably -60°C or higher) ) Method design.

The so-called Tg of the base polymer refers to the Tg based on the homopolymer of each monomer constituting the base polymer and the weight fraction of the monomer (copolymerization ratio on a weight basis), the value obtained from the formula of Fox . The formula of Fox, as shown below, is the relational formula between the Tg of the copolymer and the glass transition temperature Tgi of the homopolymer obtained by homopolymerizing the monomers constituting the copolymer. 1/Tg=Σ(Wi/Tgi)

In the above formula of Fox, Tg represents the glass transition temperature of the copolymer (unit: K), Wi represents the weight fraction of monomer i in the copolymer (copolymerization ratio on a weight basis), and Tgi represents the average of monomer i The glass transition temperature of the polymer (unit: K). As the Tg of the homopolymer, the value described in the known data can be used.

As Tg of a homopolymer, the following value can be used specifically, for example. 2-ethylhexyl acrylate -70°C N-butyl acrylate -55°C Acrylic acid 106°C 2-Hydroxyethyl acrylate -15°C 4-Hydroxybutyl acrylate -40°C

Regarding the Tg of homopolymers other than those exemplified above, the value described in "Polymer Handbook" (3rd edition, John Wiley & Sons, Inc., 1989) can be used. When there are multiple values in the "Polymer Handbook" above, the conventional value is used. Regarding the monomers not listed in the above "Polymer Handbook", the catalog value of the monomer manufacturer is used. As the Tg of the homopolymer of the monomer which is not described in the above-mentioned "Polymer Handbook" and does not provide the catalog value of the monomer manufacturer, the measurement method described in Japanese Patent Laid-Open No. 2007-51271 can be used. The value obtained.

As a method for obtaining an acrylic polymer, for example, various polymerization methods known as acrylic polymer synthesis methods, such as a solution polymerization method, an emulsion polymerization method, a bulk polymerization method, and a suspension polymerization method, can be suitably used. Among these polymerization methods, a solution polymerization method can be preferably used. As a method of supplying monomers when performing solution polymerization, a one-time addition method, a continuous supply (dropping) method, a batch supply (dropping) method, etc., in which the entire amount of the monomer components are supplied at once can be suitably adopted. The polymerization temperature can be appropriately selected according to the types of monomers and solvents used, the types of polymerization initiators, etc., and is preferably 20°C or higher, more preferably 30°C or higher, still more preferably 40°C or higher, and more preferably 170°C or lower, more preferably 160°C or lower, and still more preferably 140°C or lower. As a method for obtaining acrylic polymer, photopolymerization (typically, in the presence of a photopolymerization initiator) by irradiation with light such as UV (ultraviolet), or irradiation with radiation such as β rays and γ rays can be used Active energy ray irradiation polymerization such as radiation polymerization.

The solvent (polymerization solvent) used in the solution polymerization can be appropriately selected from any suitable organic solvents. For example, aromatic compounds (typically, aromatic hydrocarbons) such as toluene, acetates such as ethyl acetate, aliphatic or alicyclic hydrocarbons such as hexane or cyclohexane, etc. are mentioned.

The initiator (polymerization initiator) used in the polymerization can be appropriately selected from any suitable polymerization initiators according to the type of polymerization method. The polymerization initiator may be only one type or two or more types. Examples of such polymerization initiators include azo polymerization initiators such as 2,2'-azobisisobutyronitrile (AIBN); persulfates such as potassium persulfate; benzyl peroxide, peroxy Peroxide-based initiators such as hydrogen oxide; substituted ethane-based initiators such as phenyl-substituted ethane; aromatic carbonyl compounds, etc. As another example of the polymerization initiator, a redox initiator using a combination of a peroxide and a reducing agent can be cited.

The amount of the polymerization initiator used is preferably 0.005 part by weight to 1 part by weight, and more preferably 0.01 part by weight to 1 part by weight relative to 100 parts by weight of all monomer components.

The Mw of the acrylic polymer is preferably 10×10 ⁴ ～500×10 ⁴ , more preferably 10×10 ⁴ ～150×10 ⁴ , still more preferably 20×10 ⁴ ～75×10 ⁴ , particularly preferably 35 ×10 ⁴ ～65×10 ⁴ . Here, Mw means a value obtained by GPC (gel permeation chromatography) in terms of standard polystyrene conversion. As the GPC device, for example, the model name "HLC-8320GPC" (column: TSKgel GMH-H(S), manufactured by Tosoh) can be used.

(Adhesion imparting resin) In terms of further expressing the effect of the present invention, the acrylic adhesive may contain an adhesion-imparting resin. Examples of adhesion-imparting resins include: rosin-based adhesion-imparting resins, terpene-based adhesion-imparting resins, hydrocarbon-based adhesion-imparting resins, epoxy-type adhesion-imparting resins, polyamide-based adhesion-imparting resins, elastic system adhesion-imparting resins, phenol Adhesion imparting resin, ketone-based adhesion imparting resin, etc. The adhesion-imparting resin may be only one type or two or more types.

As the usage amount of the adhesion imparting resin, in terms of further expressing the effect of the present invention, relative to 100 parts by weight of the base polymer, preferably 5 parts by weight to 70 parts by weight, more preferably 10 parts by weight to 60 parts by weight Parts, more preferably 15 parts by weight to 50 parts by weight, still more preferably 20 parts by weight to 45 parts by weight, particularly preferably 25 parts by weight to 40 parts by weight, most preferably 25 parts by weight to 35 parts by weight.

In terms of further expressing the effect of the present invention, the adhesion-imparting resin preferably contains adhesion-imparting resin TL having a softening point of less than 105°C. Adhesion imparting resin TL can effectively help improve the deformability of the adhesive layer in the opposite direction (shear direction). From the viewpoint of obtaining a higher deformability improvement effect, the softening point of the adhesion-imparting resin used as the adhesion-imparting resin TL is preferably 50°C to 103°C, more preferably 60°C to 100°C, and more preferably 65°C to 95°C, particularly preferably 70°C to 90°C, most preferably 75°C to 85°C.

The softening point of the adhesion imparting resin is defined as the value measured based on the softening point test method (Ring and Ball method) specified in JIS K5902 and JIS K2207. Specifically, melt the sample as quickly as possible at a low temperature, and fill it in a ring placed on a flat metal plate, taking care not to foam. After cooling, use a slightly heated knife to cut off the part that overflows from the plane of the upper end of the containing ring. Then, put the holder (ring table) into a glass container (heating bath) with a diameter of 85 mm or more and a height of 127 mm or more, and inject glycerin to a depth of 90 mm or more. Then, the steel ball (diameter 9.5 mm, weight 3.5 g) and the ring filled with the sample are immersed in the glycerin in a non-contact manner, and the temperature of the glycerin is kept at 20°C±5°C for 15 minutes. Then, place the steel ball in the center of the sample surface in the ring, and place it in a fixed position on the holder. Then, keep the distance from the upper end of the ring to the glycerin surface at 50 mm, place a thermometer so that the center of the mercury ball of the thermometer is at the same height as the center of the ring, and heat the container. The flame of the Bunsen burner used for heating is located between the center and the edge of the bottom of the container, heating evenly. Furthermore, the rising rate of the bath temperature after heating starts to 40°C must be 5.0±0.5°C per minute. The sample gradually softens and flows down from the circulation. Read the temperature when it finally touches the bottom plate and use it as the softening point. The softening point is measured at more than two at the same time, and the average value is used.

As the usage amount of the adhesion imparting resin TL, in terms of further expressing the effects of the present invention, relative to 100 parts by weight of the base polymer, it is preferably 5 parts by weight to 50 parts by weight, more preferably 10 parts by weight to 45 parts by weight. Parts by weight, more preferably 15 parts by weight to 40 parts by weight, particularly preferably 20 parts by weight to 35 parts by weight, most preferably 25 parts by weight to 32 parts by weight.

As the adhesion-imparting resin TL, one or two or more suitably selected from the above-exemplified adhesion-imparting resins whose softening point is less than 105°C can be used. The adhesion-imparting resin TL preferably contains a rosin-based resin.

Examples of rosin-based resins that can be preferably used as the adhesion-imparting resin TL include rosin esters such as unmodified rosin ester or modified rosin ester. Examples of modified rosin esters include hydrogenated rosin esters.

In terms of further expressing the effects of the present invention, the adhesion-imparting resin TL preferably contains hydrogenated rosin ester. As the hydrogenated rosin ester, in terms of further expressing the effects of the present invention, the softening point is preferably less than 105°C, more preferably 50°C to 100°C, still more preferably 60°C to 90°C, and particularly preferably 70℃～85℃, preferably 75℃～85℃.

The adhesion-imparting resin TL may contain non-hydrogenated rosin ester. Here, the term "non-hydrogenated rosin esters" includes the concept of those other than hydrogenated rosin esters among the above-mentioned rosin esters. Examples of non-hydrogenated rosin esters include unmodified rosin esters, disproportionated rosin esters, and polymerized rosin esters.

As the non-hydrogenated rosin ester, in terms of further exhibiting the effects of the present invention, the softening point is preferably less than 105°C, more preferably 50°C to 100°C, and still more preferably 60°C to 90°C, particularly preferably It is 70℃～85℃, the best is 75℃～85℃.

The adhesion-imparting resin TL may contain other adhesion-imparting resins in addition to rosin-based resins. As other adhesion-imparting resins, one or two or more suitably selected from the above-exemplified adhesion-imparting resins whose softening point is less than 105°C can be used. The adhesion-imparting resin TL may contain rosin resin and terpene resin, for example.

As the content ratio of the rosin-based resin in the entire adhesion-imparting resin TL, in terms of further expressing the effects of the present invention, it is preferably more than 50% by weight, more preferably 55% to 100% by weight, and further It is preferably 60% to 99% by weight, particularly preferably 65% to 97% by weight, most preferably 75% to 97% by weight.

In terms of further expressing the effects of the present invention, the adhesion-imparting resin can be combined with adhesion-imparting resin TL and adhesion-imparting resin TH having a softening point of 105°C or higher (preferably 105°C to 170°C).

As the adhesion-imparting resin TH, one or two or more suitably selected from the above-exemplified adhesion-imparting resins having a softening point of 105°C or higher can be used. The adhesion-imparting resin TH may contain at least one selected from rosin-based adhesion-imparting resins (for example, rosin esters) and terpene-based adhesion-imparting resins (for example, terpene phenol resin).

(Crosslinking agent) A crosslinking agent can be included in the acrylic adhesive. The crosslinking agent may be only one type or two or more types. Through the use of crosslinking agent, it can impart a moderate cohesive force to the acrylic adhesive. The cross-linking agent can also be helpful for adjusting the offset distance and return distance in the retention test. The acrylic adhesive containing a crosslinking agent can be obtained, for example, by using an adhesive composition containing the crosslinking agent and forming an adhesive layer. The cross-linking agent may be contained in the acrylic adhesive in the form after the cross-linking reaction, the form before the cross-linking reaction, the form in which the cross-linking reaction partially undergoes the cross-linking reaction, and the intermediate or composite form of these. The crosslinking agent is typically contained in the acrylic adhesive mainly in the form after the crosslinking reaction.

In terms of further expressing the effects of the present invention, the amount of crosslinking agent used relative to 100 parts by weight of the base polymer is preferably 0.005 parts by weight to 10 parts by weight, more preferably 0.01 parts by weight to 7 parts by weight, Furthermore, it is preferably 0.05 to 5 parts by weight, particularly preferably 0.1 to 4 parts by weight, and most preferably 1 to 3 parts by weight.

Examples of crosslinking agents include isocyanate-based crosslinking agents, epoxy-based crosslinking agents, silicone-based crosslinking agents, oxazoline-based crosslinking agents, aziridine-based crosslinking agents, and silane-based crosslinking agents Cross-linking agent, alkyl etherified melamine-based cross-linking agent, metal chelate-based cross-linking agent, peroxide-based cross-linking agent, etc., in terms of further expressing the effects of the present invention, isocyanate-based cross-linking is preferred An epoxy-based crosslinking agent, and more preferably an isocyanate-based crosslinking agent.

The isocyanate-based crosslinking agent can be used for compounds having two or more isocyanate groups (containing isocyanate regeneration type functional groups that temporarily protect the isocyanate groups by blocking agents or quantification) in one molecule. Examples of the isocyanate-based crosslinking agent include aromatic isocyanates such as toluene diisocyanate and xylene diisocyanate; alicyclic isocyanates such as isophorone diisocyanate; aliphatic isocyanates such as hexamethylene diisocyanate and the like.

As the isocyanate-based crosslinking agent, more specifically, for example, lower aliphatic polyisocyanates such as butylene diisocyanate and hexamethylene diisocyanate; cyclopentyl diisocyanate, cyclohexyl diisocyanate, isocyanate, etc. Cycloaliphatic isocyanates such as phorone diisocyanate; 2,4-toluene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate, polymethylene polyphenyl isocyanate and other aromatics Diisocyanates; Trimethylolpropane/toluene diisocyanate trimer adduct (for example, Tosoh Corporation, trade name Corona L), trimethylolpropane/hexamethylene diisocyanate trimer adduct ( For example, Tosoh Company, trade name: Coronate HL), hexamethylene diisocyanate isocyanurate (for example, Tosoh Company, trade name: Coronaate HX) and other isocyanate adducts; xylylene diisocyanate Trimethylolpropane adduct (for example, manufactured by Mitsui Chemicals, trade name: Takenate D110N), trimethylolpropane adduct of xylylene diisocyanate (for example, manufactured by Mitsui Chemicals, trade name: Takenate D120N) , Trimethylolpropane adduct of isophorone diisocyanate (for example, manufactured by Mitsui Chemicals, trade name: Takenate D140N), trimethylolpropane adduct of hexamethylene diisocyanate (for example, Mitsui Chemicals) Manufacture, trade name: Takenate D160N); polyether polyisocyanate, polyester polyisocyanate, and their adducts with various polyols; with isocyanurate bond, biuret bond, allophanate bond And other multifunctional polyisocyanates. Among these, aromatic isocyanate and alicyclic isocyanate are preferable in terms of achieving both deformability and cohesive force in a good balance.

In terms of further expressing the effects of the present invention, the amount of the isocyanate-based crosslinking agent used relative to 100 parts by weight of the base polymer is preferably 0.005 parts by weight to 10 parts by weight, more preferably 0.01 parts by weight to 7 parts by weight Parts, more preferably 0.05 parts by weight to 5 parts by weight, particularly preferably 0.1 parts by weight to 4 parts by weight, most preferably 1 part by weight to 3 parts by weight.

When the monomer component constituting the acrylic polymer contains a hydroxyl-containing monomer, the weight ratio of the isocyanate-based crosslinking agent/hydroxy-containing monomer is preferably more than 20 and less than 50, more preferably 22-45, still more preferably 25-40, particularly preferably 27-40, most preferably 30-35.

When the acrylic adhesive contains the adhesion-imparting resin TL with a softening point of 105° C. or less, the weight of the adhesion-imparting resin TL/isocyanate-based crosslinking agent is preferably more than 2 and less than 15, more preferably 5-13, still more preferably 7-12, and particularly preferably 7-11.

As an epoxy-based crosslinking agent, it can be used for a multifunctional epoxy compound having two or more epoxy groups in one molecule. Examples of epoxy-based crosslinking agents include: N,N,N',N'-tetraglycidyl-meta-xylylenediamine, diglycidylaniline, 1,3-bis(N,N-di Glycidyl amino methyl) cyclohexane, 1,6-hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, polyethylene two Alcohol diglycidyl ether, polypropylene glycol diglycidyl ether, sorbitol polyglycidyl ether, glycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, polyglycerol polyglycidyl ether, sorbitan polyglycidyl ether, three Hydroxymethyl propane polyglycidyl ether, diglycidyl adipate, diglycidyl phthalate, triglycidyl-tris(2-hydroxyethyl) isocyanurate, resorcinol diglycidyl Glycidyl ether, bisphenol S-diglycidyl ether, epoxy resin having two or more epoxy groups in the molecule, etc. As a commercially available product of an epoxy-based crosslinking agent, for example, trade names "Tetrad C" and "Tetrad X" manufactured by Mitsubishi Gas Chemical Co., Ltd. can be cited.

In terms of further expressing the effects of the present invention, the amount of epoxy-based crosslinking agent used relative to 100 parts by weight of the base polymer is preferably 0.005 parts by weight to 10 parts by weight, more preferably 0.01 parts by weight to 5 parts by weight. Parts by weight, more preferably 0.015 parts by weight to 1 part by weight, particularly preferably 0.15 parts by weight to 0.5 parts by weight, most preferably 0.015 parts by weight to 0.3 parts by weight.

(Other ingredients) Acrylic adhesives can contain leveling agents, cross-linking aids, plasticizers, softeners, fillers, antistatic agents, anti-aging agents, ultraviolet absorbers, antioxidants, and light stabilizers as needed. In the usual various additives. Regarding such various additives, conventionally known additives can be used.

≪Antistatic layer≫ The adhesive film of the present invention may have an antistatic layer on the surface of the substrate layer opposite to the surface with the adhesive layer. By providing the adhesive film of the present invention with an antistatic layer on the surface of the substrate layer opposite to the surface with the adhesive layer, the charge of the adhesive film itself can be suppressed, and dust becomes difficult to adsorb, which becomes a preferred aspect.

As the antistatic layer, for example, a method of coating an antistatic resin or a conductive polymer containing an antistatic agent and a resin component, or a conductive resin containing a conductive substance, or a method of vapor deposition or plating a conductive substance method.

Examples of the antistatic agent contained in the antistatic resin include: quaternary ammonium salts, pyridinium salts, cationic antistatic agents having cationic functional groups such as primary, secondary, and tertiary amine groups; sulfonates , Sulfate, phosphonate, phosphate and other anionic antistatic agents with anionic functional groups; amphoteric type such as alkyl betaine and its derivatives, imidazoline and its derivatives, alanine and its derivatives Antistatic agent; non-ionic antistatic agent such as amino alcohol and its derivatives, glycerin and its derivatives, polyethylene glycol and its derivatives; will have the above-mentioned cationic, anionic, zwitterionic ionic conductivity Ion-conducting polymer obtained by polymerization or copolymerization of monomers. These antistatic agents may be only one type or two or more types.

Examples of cationic antistatic agents include: alkyl trimethyl ammonium salt, amide propyl trimethyl ammonium methyl sulfate, alkyl benzyl methyl ammonium salt, and acetylcholine chloride , Poly(dimethylaminoethyl methacrylate) and other (meth)acrylate copolymers with quaternary ammonium groups; polyvinylbenzyltrimethylammonium chloride and other styrene copolymers with quaternary ammonium groups; Polydiallyldimethylammonium chloride and other diallylamine copolymers with quaternary ammonium groups. These antistatic agents may be only one type or two or more types.

As an anionic antistatic agent, for example, alkyl sulfonate, alkylbenzene sulfonate, alkyl sulfate ester salt, alkyl ethoxy sulfate ester salt, alkyl phosphate ester salt, sulfonic acid group-containing The styrene copolymer and so on. These antistatic agents may be only one type or two or more types.

As the zwitterionic antistatic agent, for example, alkyl betaine, alkyl imidazolium betaine, carbonyl betaine graft copolymer and the like can be cited. These antistatic agents may be only one type or two or more types.

Examples of non-ionic antistatic agents include: fatty acid hydroxyalkyl amide, di(2-hydroxyethyl)alkylamine, polyoxyethylene alkylamine, fatty acid glyceride, polyoxyethylene glycol fatty acid Ester, sorbitan fatty acid ester, polyoxysorbitan fatty acid ester, polyoxyethylene alkyl phenyl ether, polyoxyethylene alkyl ether, polyethylene glycol, polyoxyethylene diamine, containing polyether and Polyester and polyamide copolymer, methoxy polyethylene glycol (meth)acrylate, etc. These antistatic agents may be only one type or two or more types.

As a conductive polymer, polyaniline, polypyrrole, polythiophene, etc. are mentioned, for example. These conductive polymers may be only one type or two or more types.

Examples of conductive materials 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 cobalt. , Copper iodide and their alloys or mixtures, etc. These conductive substances may be only one type or two or more types.

As the resin component used in the antistatic resin and the conductive resin, for example, general-purpose resins such as polyester resin, acrylic resin, polyethylene resin, urethane resin, melamine resin, and epoxy resin can be used. Furthermore, in the case of a polymer type antistatic agent, the resin component may not be included. Also, as a component of the antistatic resin, it may also contain methylolated or hydroxyalkylated melamine compounds, urea compounds, glyoxal compounds, acrylamide compounds; epoxy compounds; isocyanate compounds, etc. As a crosslinking agent.

As a method of forming the antistatic layer, for example, the above-mentioned antistatic resin, conductive polymer, conductive resin, etc. can be diluted with an organic solvent or a solvent such as water, and the coating liquid can be applied to a substrate, etc., and dried. And formed.

Examples of the diluted solution used in the formation of the antistatic layer include: methyl ethyl ketone, acetone, ethyl acetate, tetrahydrofuran, dioxane, cyclohexanone, n-hexane, toluene, xylene, methanol, ethanol , N-propanol, isopropanol, water, etc. These solvents may be only one type or two or more types.

Regarding the coating method in the formation of the antistatic layer, any suitable coating method can be suitably used. Examples of such coating methods include roll coating, gravure coating, reverse coating, roll brushing, spray coating, air knife coating, impregnation, curtain coating, and the like.

As a method of vapor deposition or plating of the conductive material, any suitable method can be suitably used. Examples of such methods include vacuum vapor deposition, sputtering, ion plating, chemical vapor deposition, spray thermal decomposition, chemical plating, and electroplating.

The thickness of the antistatic layer can be any suitable thickness within a range that does not impair the effects of the present invention. In terms of further expressing the effects of the present invention, the thickness of the antistatic layer is preferably 0.001 μm to 5 μm, more preferably 0.005 μm to 1 μm.

≪Face coating≫ The adhesive film of the present invention may have a top coat on the surface of the substrate layer opposite to the surface with the adhesive layer. The top coat preferably contains a binder, and more preferably contains a binder and a slip agent. By providing the adhesive film of the present invention with a top coat, the scratch resistance of the adhesive film can be improved, which becomes a preferred aspect.

＜Adhesives＞ Any suitable resin can be used for the binder within a range that does not impair the effects of the present invention. As such a resin, it is preferable that it is at least 1 sort(s) chosen from the group which consists of a polyester resin and a urethane-type resin in the point which can express the effect of this invention further.

(polyester resin) When the adhesive contains a polyester resin, the polyester resin may be only one type or two or more types.

The polyester resin is preferably a resin containing polyester as a main component. The content ratio of the polyester in the polyester resin is preferably more than 50% by weight, more preferably 75% by weight or more, and still more preferably 90% by weight or more.

The polyester preferably has at least one selected from the group consisting of polycarboxylic acids (preferably dicarboxylic acids) and their derivatives (anhydrides, esters, halides, etc.) of polycarboxylic acids having two or more carboxyl groups in one molecule. A structure in which one compound (polycarboxylic acid component) is condensed with at least one compound (polyol component) selected from polyols (preferably diols) having two or more hydroxyl groups in one molecule.

As a compound that can be used as a polycarboxylic acid component, for example, oxalic acid, malonic acid, difluoromalonic acid, alkylmalonic acid, succinic acid, tetrafluorosuccinic acid, alkylsuccinic acid, (±)- Malic acid, mesotartaric acid, itaconic acid, maleic acid, methyl maleic acid, fumaric acid, methyl fumaric acid, acetylene dicarboxylic acid, glutaric acid, six Fluoroglutaric acid, methylglutaric acid, glutaconic acid, adipic acid, dithioadipic acid, methyl adipic acid, dimethyl adipic acid, tetramethyl adipic acid, methylene Adipic acid, muconic acid, galactaric acid, pimelic acid, suberic acid, perfluorosuccinic acid, 3,3,6,6-tetramethyl suberic acid, azelaic acid, sebacic acid, Aliphatic dicarboxylic acids such as perfluorosebacic acid, tridecane dicarboxylic acid, dodecyl dicarboxylic acid, tridecyl dicarboxylic acid, tetradecyl dicarboxylic acid; cycloalkyl dicarboxylic acid (for example 1,4-Cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid), 1,4-(2-Norene) dicarboxylic acid, 5-Norene-2,3-dicarboxylate Acid (bicycloheptene dicarboxylic acid), adamantane dicarboxylic acid, spiroheptane dicarboxylic acid and other alicyclic dicarboxylic acids; phthalic acid, isophthalic acid, dithioisophthalic acid, methyl isophthalic acid Phthalic acid, dimethyl isophthalic acid, chloroisophthalic acid, dichloroisophthalic acid, terephthalic acid, methyl terephthalic acid, dimethyl terephthalic acid, chloroterephthalic acid , Bromoterephthalic acid, naphthalene dicarboxylic acid, quinone dicarboxylic acid, anthracene dicarboxylic acid, biphenyl dicarboxylic acid, biphenyl dicarboxylic acid, dimethyl biphenyl dicarboxylic acid, 4,4' '-Pterylene dicarboxylic acid, 4,4''-pterylene dicarboxylic acid, bibenzyl dicarboxylic acid, azobenzene dicarboxylic acid, homophthalic acid, phenylene diacetic acid, phenylene Dipropionic acid, naphthalenedicarboxylic acid, naphthalenedipropionic acid, biphenyl diacetic acid, biphenyl dipropionic acid, 3,3'-[4,4'-(methylene di-p-biphenyl) dipropionic acid , 4,4'-bibenzyldiacetic acid, 3,3'(4,4'-bibenzyl)dipropionic acid, oxobis-p-phenylene diacetic acid and other aromatic dicarboxylic acids; any of the above Anhydrides of carboxylic acids; esters of any of the above-mentioned polycarboxylic acids (such as alkyl esters, monoesters, diesters, etc.); any of the above-mentioned carboxylic acid halides (such as dicarboxylic acid chloride) and the like.

Preferred examples of compounds that can be used as the polycarboxylic acid component include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, and naphthalenedicarboxylic acid and their anhydrides; adipic acid, sebacic acid, Aliphatic dicarboxylic acids such as azelaic acid, succinic acid, fumaric acid, maleic acid, bicycloheptene dicarboxylic acid, 1,4-cyclohexane dicarboxylic acid and their anhydrides; among the above-mentioned dicarboxylic acids Lower alkyl esters (for example, esters with monoalcohols having 1 to 3 carbon atoms) and the like.

Examples of compounds that can be used as the polyol component include ethylene glycol, propylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, and neopentyl glycol. 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-diethyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol, benzenedimethanol, Hydrogenated bisphenol A, bisphenol A and other glycols. As another example, alkylene oxide adducts of these compounds (for example, ethylene oxide adducts, propylene oxide adducts, etc.) can be cited.

The polyester resin preferably contains a water-dispersible polyester, and more preferably contains a water-dispersible polyester as a main component. Such water-dispersible polyesters can be improved by the introduction of hydrophilic functional groups (e.g., at least one selected from hydrophilic functional groups such as sulfonic acid metal salt groups, carboxyl groups, ether groups, phosphoric acid groups, etc.) into the polymer to improve water dispersion. Sexual polyester. Thus, as a method of introducing a hydrophilic functional group into a polymer, for example, a method of copolymerizing a compound having a hydrophilic functional group, a polyester or its precursor (such as a polycarboxylic acid component, a polyol component, the Oligomers, etc.) modified to produce hydrophilic functional groups. Any suitable method. As a preferable water-dispersible polyester, a polyester (copolyester) formed by copolymerization of a compound having a hydrophilic functional group can be cited.

The polyester resin used as the binder can be one with saturated polyester as the main component, or one with unsaturated polyester as the main component. The polyester resin is preferably a saturated polyester as its main component, and more preferably a saturated polyester that imparts water dispersibility (for example, a saturated copolyester). Such a polyester resin (which may be prepared in the form of an aqueous dispersion) can be synthesized by any suitable method, or a commercially available product can be easily obtained.

The molecular weight of the polyester resin is the weight average molecular weight (Mw) in terms of standard polystyrene measured by gel permeation chromatography (GPC), preferably 0.5×10 ⁴ to 15×10 ⁴ , more preferably 1 ×10 ⁴ ～6×10 ⁴ .

The glass transition temperature (Tg) of the polyester resin is preferably 0°C to 100°C, more preferably 10°C to 80°C.

(Urethane resin) When a urethane-based resin is contained in the adhesive, the urethane-based resin may be only one type or two or more types.

The urethane-based resin is preferably a urethane-based resin obtained by curing a composition containing a polyol (A) and a polyfunctional isocyanate compound (B).

As the polyol (A), there may be only one type or two or more types.

As the polyol (A), any suitable polyol can be used as long as it is a polyol having two or more OH groups. As such a polyol (A), for example, a polyol having 2 OH groups (diol), a polyol having 3 OH groups (triol), a polyol having 4 OH groups (tetraol) ), polyols with 5 OH groups (pentaol), polyols with 6 OH groups (hexaol), etc.

As the polyol (A), it is preferable to use diols such as ethylene glycol or propylene glycol having two or more OH groups as essential components. If diol is used as an essential component in this way, for example, it is possible to provide a urethane-based curable resin having excellent strength of the cured coating film, and excellent adhesion to the substrate or retention of additives. The content ratio of the diol in the polyol (A) is preferably 30% by weight to 100% by weight, more preferably 50% by weight to 100% by weight, still more preferably 70% by weight to 100% by weight, and still more preferably 90% by weight to 100% by weight, particularly preferably 95% to 100% by weight, and most preferably substantially 100% by weight.

As the polyol (A), for example, ethylene glycol, diethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, 3-methyl-1, 5-pentanediol, 2-butyl-2-ethyl-1,3-propanediol, 2,4-diethyl-1,5-pentanediol, 1,2-hexanediol, 1,6- Hexanediol, 1,8-octanediol, 1,9-nonanediol, 2-methyl-1,8-octanediol, 1,8-decanediol, octadecanediol, glycerin, tri Methylolpropane, pentaerythritol, hexanetriol, polyethylene glycol, polypropylene glycol, polyester polyol, polyether polyol, polycaprolactone polyol, polycarbonate polyol, castor oil-based polyol, etc.

As a polyester polyol, it can obtain by the esterification reaction of a polyol component and an acid component, for example.

Examples of acid components include succinic acid, methylsuccinic acid, adipic acid, pimelic acid, azelaic acid, sebacic acid, 1,12-dodecanedioic acid, 1,14-tetradecanedioic acid Acid, dimer acid, 2-methyl-1,4-cyclohexanedicarboxylic acid, 2-ethyl-1,4-cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, o-benzene Dicarboxylic acid, isophthalic acid, terephthalic acid, 1,4-naphthalene dicarboxylic acid, 4,4'-biphenyl dicarboxylic acid, these acid anhydrides, etc.

Examples of polyether polyols include water, low molecular weight polyols (propylene glycol, ethylene glycol, glycerin, trimethylolpropane, pentaerythritol, etc.), bisphenols (bisphenol A, etc.), dihydroxy Benzene (catechol, resorcinol, hydroquinone, etc.) is used as a starting agent, and polyalkylene oxides such as ethylene oxide, propylene oxide, butylene oxide, etc. Ether polyol. Specifically, for example, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and the like can be cited.

Examples of polycaprolactone polyols include caprolactone polyester diols obtained by ring-opening polymerization of cyclic ester monomers such as ε-caprolactone and σ-valerolactone.

Examples of polycarbonate polyols include: polycarbonate polyols obtained by subjecting the above-mentioned polyol component and phosgene to polycondensation reaction; the above-mentioned polyol component and dimethyl carbonate, diethyl carbonate, and dipropylene carbonate Ester, diisopropyl carbonate, dibutyl carbonate, ethyl butyl carbonate, ethylene carbonate, propylene carbonate, diphenyl carbonate, dibenzyl carbonate and other carbonic acid diesters are obtained by transesterification condensation Polycarbonate polyol; copolymerized polycarbonate polyol obtained by using two or more of the above-mentioned polyol components; polycarbonate polyol obtained by esterification of the above-mentioned various polycarbonate polyols and carboxyl-containing compounds ; Polycarbonate polyols obtained by etherification of the above-mentioned various polycarbonate polyols and hydroxyl-containing compounds; polycarbonate polyols obtained by transesterification of the above-mentioned various polycarbonate polyols and ester compounds ; Polycarbonate polyols obtained by transesterification of the above-mentioned various polycarbonate polyols and hydroxyl-containing compounds; Polyester-based polyols obtained by polycondensation of the above-mentioned various polycarbonate polyols and dicarboxylic acid compounds Carbonate polyols; copolyether polycarbonate polyols obtained by copolymerizing various polycarbonate polyols and alkylene oxides mentioned above.

Examples of castor oil-based polyols include castor oil-based polyols obtained by reacting castor oil fatty acids with the above-mentioned polyol components. Specifically, for example, a castor oil-based polyol obtained by reacting castor oil fatty acid with polypropylene glycol is mentioned.

The polyfunctional isocyanate compound (B) may be only one type or two or more types.

As the polyfunctional isocyanate compound (B), any suitable polyfunctional isocyanate compound that can be used in the urethane reaction can be used. As such a polyfunctional isocyanate compound (B), a polyfunctional aliphatic isocyanate compound, a polyfunctional alicyclic isocyanate, a polyfunctional aromatic isocyanate compound, etc. are mentioned, for example.

Examples of polyfunctional aliphatic isocyanate compounds include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 1,3-butylene diisocyanate, dodecamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, etc.

Examples of polyfunctional alicyclic isocyanate compounds include 1,3-cyclopentene diisocyanate, 1,3-cyclohexane diisocyanate, 1,4-cyclohexane diisocyanate, isophorone diisocyanate, Hydrogenated diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated toluene diisocyanate, hydrogenated tetramethylxylylene diisocyanate, etc.

As the polyfunctional aromatic diisocyanate compound, for example, phenylene diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 2,2'-diphenylmethane diisocyanate, 4, 4'-diphenylmethane diisocyanate, 4,4'-toluidine diisocyanate, 4,4'-diphenyl ether diisocyanate, 4,4'-diphenyl diisocyanate, 1,5-naphthalene diisocyanate, Xylylene diisocyanate, etc.

Examples of the polyfunctional isocyanate compound (B) include trimethylolpropane adducts of various polyfunctional isocyanate compounds as described above, biurets formed by reacting with water, and those having isocyanurate rings. Trimer and so on. Also, these can be used together.

As the content ratio of the polyfunctional isocyanate compound (B), the polyfunctional isocyanate compound (B) is preferably 5 wt% to 60 wt%, more preferably 8 wt% to 60 wt%, relative to the polyol (A) Preferably it is 10 weight%-60 weight%. By adjusting the content ratio of the polyfunctional isocyanate compound (B) within the above range, the effect of the present invention can be further expressed.

Typically, a urethane-based resin is obtained by curing a composition containing a polyol (A) and a polyfunctional isocyanate compound (B). In such a composition, any suitable other components other than the polyol (A) and the polyfunctional isocyanate compound (B) can be contained within a range that does not impair the effects of the present invention. Examples of such other components include: catalysts, resin components other than polyurethane resins, adhesion imparting agents, inorganic fillers, organic fillers, metal powders, pigments, foils, softeners , Plasticizers, anti-aging agents, conductive agents, antioxidants, ultraviolet absorbers, light stabilizers, surface lubricants, leveling agents, anti-corrosion agents, heat-resistant stabilizers, polymerization inhibitors, lubricants, solvents, etc.

As a method of curing a composition containing a polyol (A) and a polyfunctional isocyanate compound (B) to obtain a urethane-based resin, it is possible to use bulk polymerization or Any suitable method such as urethane reaction method such as solution polymerization.

(Other resins) The top coat can contain other resins (for example selected from acrylic resins, acrylic-styrene resins, acrylic-poly At least one of silicone resin, polysilicone resin, polysilazane resin, fluororesin, and polyolefin resin) is used as a binder. The preferred implementation aspect of the top coat is the following form: the binder of the top coat essentially only contains at least one selected from the group consisting of polyester resin and urethane resin, selected from polyester The ratio of at least one of the resin and the urethane-based resin in the adhesive is preferably 98% by weight to 100% by weight, more preferably 99% by weight to 100% by weight, and more preferably It is 99.5% by weight to 100% by weight. The ratio of the adhesive in the entire top coat layer is preferably 15% by weight to 95% by weight, more preferably 25% by weight to 80% by weight.

＜Slip agent＞ As the slip agent, an ester containing a higher fatty acid and a higher alcohol (hereinafter sometimes referred to as "wax ester") is preferred.

The "higher fatty acid" is preferably a carboxylic acid having 8 or more carbon atoms, more preferably 10 or more carbon atoms, and still more preferably 10-40. The carboxylic acid is preferably a monocarboxylic acid.

The "higher alcohol" is preferably an alcohol having 6 or more carbon atoms, more preferably 10 or more carbon atoms, and still more preferably 10-40. The alcohol is preferably a monohydric or dihydric alcohol, more preferably a monohydric alcohol.

The top coat of the composition containing this wax ester and the above-mentioned adhesive is not easy to whiten even if it is kept under high temperature and humidity conditions. Therefore, an adhesive film with a substrate with such a top coat can be of higher appearance quality.

As a reason for achieving excellent whitening resistance (for example, a property that is not easy to whiten even if kept under high temperature and humidity conditions) by the top coat of the above composition, the following reasons are considered, for example. That is, it is presumed that the previously used silicone-based lubricant has the function of imparting lubricity to the surface of the top coat by bleeding out to the surface. However, the degree of exudation of these silicone-based lubricants is easy to change depending on the storage conditions (temperature, humidity, elapsed time, etc.). Therefore, for example, if it is kept under normal storage conditions (e.g. 25°C, 50%RH), a way to obtain moderate lubricity after a long time (e.g. about 3 months) has passed since the adhesive film has just been manufactured Set the usage amount of the silicone-based slip agent, and when the adhesive film is stored under high temperature and humidity conditions (for example, 60°C, 95% RH) for 2 weeks, the slip agent excessively oozes. Such excessively exuded silicone-based lubricant may whiten the top coat (even the adhesive film).

As a preferred embodiment of the top coat, a specific combination of wax ester as a slip agent and polyester resin as a binder is used. If it is a combination of such a slip agent and a binder, the degree of exudation of wax ester from the top coat is not easily affected by storage conditions. Thereby, the whitening resistance of the adhesive film can be improved.

As the wax ester, one or more of the compounds represented by general formula (W) can be preferably used. X-COO-Y (W)

X and Y in the formula (W) are independent of each other, and are preferably a hydrocarbon group having 10 to 40 carbon atoms, and the number of carbon atoms is more preferably 10 to 35, more preferably 14 to 35, and particularly preferably 20 to 32. If the number of carbon atoms is too small, the effect of imparting lubricity to the top coat may be insufficient. The above-mentioned hydrocarbon group may be a saturated hydrocarbon group or an unsaturated hydrocarbon group. The above-mentioned hydrocarbon group is preferably a saturated hydrocarbon group. In addition, the above-mentioned hydrocarbon group may be a structure containing an aromatic ring, a structure not containing an aromatic ring (aliphatic hydrocarbon group), or a hydrocarbon group containing an aliphatic ring structure (alicyclic hydrocarbon group), It may also be a chain (including linear and branched) hydrocarbon groups.

As the wax ester, X and Y in the formula (W) are each independently preferably a compound having a chain alkyl group having 10 to 40 carbon atoms, more preferably a linear alkyl group having 10 to 40 carbon atoms. Compound. As a specific example of such a compound, for example, beeswax wax ester (CH ₃ (CH ₂ ) ₂₄ COO(CH ₂ ) ₂₉ CH ₃ ), beeswax palmitate (CH ₃ (CH ₂ ) ₁₄ COO( CH ₂ ) ₂₉ CH ₃ ), cetyl palmitate (CH ₃ (CH ₂ ) ₁₄ COO(CH ₂ ) ₁₅ CH ₃ ), stearyl stearate (CH ₃ (CH ₂ ) ₁₆ COO(CH ₂ ) ₁₇ CH ₃ ) and so on.

The melting point of the wax ester is preferably 50°C or higher, more preferably 60°C or higher, still more preferably 70°C or higher, and particularly preferably 75°C or higher. With this wax ester, higher whitening resistance can be achieved. The melting point of the wax ester is preferably 100°C or less. This wax ester has a higher effect of imparting lubricity, so it can form a top coat with higher scratch resistance. When the melting point of the wax ester is below 100°C, it is also preferable in terms of easy preparation of an aqueous dispersion of the wax ester. As such a wax ester, for example, beeswax wax ester can be preferably used.

As the raw material of the top coat, natural wax containing this wax ester can be used. As such natural wax, based on the non-volatile content (NV), the content ratio of the above wax esters (in the case of containing two or more wax esters, the sum of the content ratios) is preferably more than 50% by weight , More preferably 65% by weight or more, and still more preferably 75% by weight or more. As such natural waxes, for example, carnauba wax (usually preferably 60% by weight or more, more preferably 70% by weight or more, and still more preferably 80% by weight or more, contains beeswax wax), Plant waxes such as palm wax; animal waxes such as beeswax and spermaceti. The melting point of this natural wax is preferably 50°C or higher, more preferably 60°C or higher, still more preferably 70°C or higher, and particularly preferably 75°C or higher. As the raw material of the top coat, chemically synthesized wax esters can be used, or refined natural waxes can be used to improve the purity of wax esters. These raw materials may be only one type or two or more types.

The proportion of the lubricant in the entire top coat layer is preferably 5 wt% to 50 wt%, more preferably 10 wt% to 40 wt%. If the content ratio of the slip agent is too small, there is a possibility that the scratch resistance may easily decrease. If the content ratio of the slip agent is too high, the effect of improving the whitening resistance is likely to become insufficient.

In addition to wax ester, the top coat can also contain other slip agents. As other lubricants, for example, petroleum waxes (paraffin wax etc.), mineral waxes (montan wax etc.), higher fatty acids (cenic acid etc.), neutral fats (palmitic acid triglyceride etc.) other than wax esters Of various waxes. In addition to wax esters, silicone-based lubricants, fluorine-based lubricants, and the like may also be contained. As a preferred embodiment of the top coat, it is substantially free of silicone-based lubricants and fluorine-based lubricants. For example, the total content of silicone-based lubricants and fluorine-based lubricants is the ratio of the overall surface coating It is preferably 0.01% by weight or less, more preferably below the detection limit.

The top coat may contain antistatic ingredients, crosslinking agents, antioxidants, colorants (pigments, dyes, etc.), fluidity regulators (thixotropic agents, tackifiers, etc.), film forming aids, and surfactants as needed. (Defoamer, dispersant, etc.), preservatives and other additives.

＜Antistatic component of top coat＞ The preferred embodiment of the top coat contains antistatic ingredients. As an antistatic component, it is a component that can prevent or inhibit the charging of the adhesive film. When an antistatic component is contained in the top coat, as the antistatic component, for example, organic or inorganic conductive materials, various antistatic agents, etc. can be used. In addition, the antistatic agent that can be used in the antistatic layer described above can also be used.

Examples of organic conductive materials include: quaternary ammonium salts, pyridinium salts, cationic antistatic agents having cationic functional groups such as primary amine groups, secondary amine groups, and tertiary amine groups; sulfonates or sulfate esters Anionic antistatic agents with anionic functional groups such as salts, phosphonates and phosphate salts; zwitterionic antistatic agents such as alkyl betaine and its derivatives, imidazoline and its derivatives, alanine and its derivatives Agent; amino alcohol and its derivatives, glycerin and its derivatives, polyethylene glycol and its derivatives and other non-ionic antistatic agents; will have the above-mentioned cationic, anionic, zwitterionic ionic conductive groups ( For example, quaternary ammonium salt group) monomers are polymerized or copolymerized to obtain ion conductive polymers; conductive polymerization of polythiophene, polyaniline, polypyrrole, polyethyleneimine, allylamine series polymers, etc. Things etc. The antistatic agent may be only one kind, or two or more kinds.

Examples of inorganic conductive materials include tin oxide, antimony oxide, indium oxide, cadmium oxide, titanium oxide, zinc oxide, indium, tin, antimony, gold, silver, copper, aluminum, nickel, chromium, titanium, iron, Cobalt, copper iodide, ITO (indium oxide/tin oxide), ATO (antimony oxide/tin oxide), etc. There may be only one type of such inorganic conductive substance, or two or more types.

Examples of antistatic agents include: cationic antistatic agents, anionic antistatic agents, zwitterionic antistatic agents, nonionic antistatic agents, and ions having the above-mentioned cationic, anionic, and zwitterionic types An ion conductive polymer obtained by polymerization or copolymerization of monomers of conductive groups.

When the top coat contains an antistatic component, it is preferable that the antistatic component contains an organic conductive substance. As the organic conductive substance, various conductive polymers can be preferably used. With this structure, both good antistatic properties and high scratch resistance can be achieved.

Examples of the conductive polymer include polythiophene, polyaniline, polypyrrole, polyethyleneimine, and allylamine-based polymers. There may be only one type of such conductive polymer, or two or more types. In addition, it can be used in combination with other antistatic components (inorganic conductive materials, antistatic agents, etc.).

The amount of the conductive polymer used is preferably 1 part by weight to 100 parts by weight, more preferably 2 parts by weight to 70 parts by weight, and more preferably 3 parts by weight relative to 100 parts by weight of the binder contained in the top coat Parts ~ 50 parts by weight. If the amount of the conductive polymer used is too small, the antistatic effect may decrease. If the amount of the conductive polymer used is too large, the compatibility of the conductive polymer in the top coat layer may become slightly insufficient, and the appearance quality of the top coat layer may decrease or the solvent resistance may decrease.

The conductive polymer preferably includes polythiophene and polyaniline. As polythiophene, the weight average molecular weight Mw in terms of polystyrene is preferably 40×10 ⁴ or less, more preferably 30×10 ⁴ or less. As polyaniline, the weight average molecular weight Mw in terms of polystyrene is preferably 50×10 ⁴ or less, and more preferably 30×10 ⁴ or less. The weight average molecular weight Mw of the conductive polymer in terms of polystyrene is preferably 0.1×10 ⁴ or more, more preferably 0.5×10 ⁴ or more. Furthermore, the term "polythiophene" in this specification refers to a polymer of unsubstituted or substituted thiophene. As a polymer of substituted thiophene, poly(3,4-ethylenedioxythiophene) etc. are mentioned, for example.

When the method of applying the coating material for forming the top coat to the substrate and drying or hardening is used as the method of forming the top coat, it is used as the conductivity used in the preparation of the coating material As the polymer, a form in which the conductive polymer is dissolved or dispersed in water (a conductive polymer aqueous solution) can be preferably used. Such a conductive polymer aqueous solution can be dissolved, for example, by dissolving a conductive polymer having a hydrophilic functional group (a conductive polymer that can be synthesized by copolymerizing a monomer having a hydrophilic functional group in the molecule). Or dispersed in water and prepared. Examples of the hydrophilic functional group include: sulfo group, amino group, amide group, imino group, hydroxyl group, mercapto group, hydrazine group, carboxyl group, quaternary ammonium group, sulfate group (-O-SO ₃ H), Phosphate ester group (for example -O-PO(OH) ₂ ) and the like. Such hydrophilic functional groups can form salts. As a commercially available product of the polythiophene aqueous solution, for example, the product name "Denatron" series manufactured by Nagase chemteX can be cited. As a commercially available product of the polyaniline sulfonic acid aqueous solution, for example, a brand name "aqua-PASS" manufactured by Mitsubishi Rayon Corporation, etc. can be cited.

In the preparation of the coating material, it is preferable to use a polythiophene aqueous solution. The polythiophene aqueous solution is preferably a polythiophene aqueous solution containing polystyrene sulfonate (PSS) (for example, a form in which PSS is added as a dopant to polythiophene). Such an aqueous solution of polythiophene may be one containing polythiophene:PSS in a mass ratio of preferably 1:1 to 1:10. The total content of polythiophene and PSS in such a polythiophene aqueous solution is preferably 1% to 5% by weight. As a commercially available product of such an aqueous solution of polythiophene, for example, the product name "Baytron" of H. C. Stark Company, etc. can be cited. Furthermore, in the case of using a polythiophene aqueous solution containing PSS as described above, the total amount of polythiophene and PSS relative to 100 parts by weight of the adhesive is preferably 5 parts by weight to 200 parts by weight, more preferably 10 parts by weight ~100 parts by weight, more preferably 25 parts by weight to 70 parts by weight.

If necessary, the top coat may contain a conductive polymer and one or more other antistatic components (organic conductive materials other than conductive polymers, inorganic conductive materials, antistatic agents, etc.). It is preferable that the top coating layer contains substantially no antistatic components other than the conductive polymer. That is, it is preferable that the antistatic component contained in the top coat substantially contains only a conductive polymer.

＜Crosslinking agent＞ The top coat preferably contains a crosslinking agent. As the cross-linking agent, cross-linking agents such as melamine-based cross-linking agents, isocyanate-based cross-linking agents, and epoxy-based cross-linking agents used in the cross-linking of ordinary resins can be appropriately selected and used. By using such a crosslinking agent, at least one effect of improvement in scratch resistance, improvement in solvent resistance, improvement in printing adhesion, and reduction in friction coefficient (that is, improvement in lubricity) can be achieved. Preferably, the crosslinking agent contains a melamine-based crosslinking agent. It may be that the cross-linking agent essentially contains only the top coat of the melamine-based cross-linking agent (melamine-based resin) (that is, substantially no cross-linking agent other than the melamine-based cross-linking agent).

＜A better aspect of top coat＞ As a preferred aspect of the top coat, when the material of the substrate layer is at least one selected from polyimide and polyether ether ketone, the top coat contains a urethane-based resin The state of the adhesive and antistatic ingredients. Thus, by using an adhesive containing a urethane-based resin as an antistatic component of the top coat, the top coat pair is made of at least one selected from polyimide and polyether ether ketone The coating formability of the surface of the substrate layer becomes excellent, it can be a good appearance, and can exhibit excellent antistatic properties.

As the adhesive of the antistatic component of the top coat, the adhesive containing polyester resin is preferred in many cases, but the material of the substrate layer is a specific base of at least one selected from polyimide and polyether ether ketone For the material layer, the adhesives containing polyester resins have low affinity, and there is a possibility that the appearance of the top coat after coating and formation may deteriorate or the excellent antistatic properties may not be exhibited. As described above, when the material of the substrate layer is at least one selected from polyimide and polyether ether ketone, if the top coat contains a urethane-based resin-containing adhesive and antistatic In the aspect of the ingredients, the coating formability of the top coat to the surface of the substrate layer becomes excellent, it can be a good appearance, and can exhibit excellent antistatic properties.

＜Formation of top coat＞ The top coat layer may preferably comprise a method of imparting to the substrate a liquid composition (coating material for forming a top coat layer) obtained by dispersing or dissolving the above-mentioned resin components and optional additives in a suitable solvent地 formed. For example, a method of applying the above-mentioned coating material to the first surface of the base material and drying it, and performing hardening treatment (heat treatment, ultraviolet treatment, etc.) if necessary, can be preferably used. The NV (non-volatile content) of the coating material is preferably 5 wt% or less, more preferably 0.05 wt% to 5 wt%, still more preferably 0.05 wt% to 1 wt%, and particularly preferably 0.10 wt% to 1 weight%. In the case of forming a top coat with a small thickness, the NV of the coating material is preferably 0.05% by weight to 0.50% by weight, more preferably 0.10% by weight to 0.30% by weight. By using a coating material with low NV in this way, a more uniform top coat can be formed.

The solvent constituting the coating material for forming the top coat layer is preferably one that can stably dissolve or disperse the top coat layer forming component. The solvent may be an organic solvent, water or a mixed solvent of these. Examples of organic solvents include esters selected from ethyl acetate; ketones such as methyl ethyl ketone, acetone, and cyclohexanone; cyclic ethers such as tetrahydrofuran (THF) and dioxane; n-hexane and cyclohexane. Aliphatic or alicyclic hydrocarbons such as alkanes; aromatic hydrocarbons such as toluene and xylene; aliphatic or alicyclic alcohols such as methanol, ethanol, n-propanol, isopropanol, and cyclohexanol; At least one of alcohol monoalkyl ether (for example, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether), glycol ethers such as dialkylene glycol monoalkyl ether, and the like. Preferably, the solvent constituting the coating material for forming the top coat layer is water or a mixed solvent mainly composed of water (for example, a mixed solvent of water and ethanol).

＜Properties of top coat＞ The thickness of the top coating is preferably 3 nm to 500 nm, more preferably 3 nm to 100 nm, and still more preferably 3 nm to 60 nm. If the thickness of the top coat is too large, the transparency (transparency) of the adhesive film may easily decrease. If the thickness of the top coat is too small, it may be difficult to form the top coat uniformly. For example, in the thickness of the top coat, the difference in the thickness of different parts may become larger. Therefore, the appearance of the adhesive film is likely to occur The fear of unevenness.

The thickness of the top coating can be grasped by observing the cross section of the top coating with a transmission electron microscope (TEM). For example, for a target sample (a substrate with a top coating or an adhesive film with a substrate, etc.), heavy metal dyeing is performed for the purpose of making the top coating clear, followed by resin embedding. The TEM observation of the section of the sample by the sectioning method can preferably use the result obtained as the thickness of the top coating. As the TEM, for example, TEM (model "H-7650") manufactured by Hitachi, etc. can be used. In the following examples, the cross-sectional image obtained under the conditions of accelerating voltage: 100 kV and magnification: 60,000 times is binarized, and the cross-sectional area of the top coat is divided by the length of the sample in the field of view. The thickness of the top coat (average thickness in the field of view). Furthermore, when the top coat can be observed clearly even without heavy metal dyeing, the heavy metal dyeing treatment can be omitted. Or, it can be based on the correlation between the thickness grasped by TEM and the detection results obtained by various thickness detection devices (such as surface roughness meters, interferometers, infrared spectrometers, various X-ray diffraction devices, etc.) Make a calibration curve and calculate it to find the thickness of the top coat.

The surface resistivity measured on the surface of the top coat is preferably 10 ¹² Ω or less, more preferably 10 ⁴ Ω～10 ¹² Ω, still more preferably 10 ⁴ Ω～10 ¹¹ Ω, especially preferably 5×10 ⁴ Ω ～10 ¹⁰ Ω, the best is 10 ⁴ Ω～10 ⁹ Ω. The adhesive film exhibiting such a surface resistivity can be preferably used as an adhesive film used in the processing or transportation of articles that need to avoid static electricity such as liquid crystal cells or semiconductor devices, for example. The value of surface resistivity can be calculated from the value of surface resistance measured under an environment of 23°C and 50%RH using a commercially available insulation resistance measuring device.

The friction coefficient of the top coat is preferably 0.4 or less. If a top coat with a low friction coefficient is made in this way, when a load is applied to the top coat (a load that will cause scratches), the load can be avoided along the surface of the top coat to reduce the friction caused by the load force. As a result, it is difficult to produce cohesive failure of the top coating (a damaged state where the top coating is damaged inside) or interface failure (a damaged state where the top coating is peeled off the back of the substrate). Therefore, the phenomenon of scratches in the adhesive film can be further prevented. As the lower limit of the friction coefficient, considering the balance with other characteristics (for example, appearance quality, printability, etc.), it is preferably 0.1 or more, and more preferably 0.15 or more. As the coefficient of friction, for example, a value obtained by rubbing the surface of the coating with a vertical load of 40 mN under a measurement environment of 23°C and 50%RH can be used. The amount of slip agent used can be set in a way to achieve a better friction coefficient. When the crosslinking density of the top coat is increased by, for example, the addition of a crosslinking agent or the adjustment of film forming conditions, the adjustment of the friction coefficient is also effective.

The adhesive film preferably has the property that its back (surface of the top coat) can be easily printed with oil-based ink (for example, using an oil-based marker). This kind of adhesive film is suitable for the following situations: in the process of processing or transporting the adherend (such as optical parts) with the adhesive film attached, the identification number of the adherend that will become the object of protection Recorded and displayed on the above-mentioned adhesive film. Therefore, it is preferable to use a surface protective film that has excellent printability in addition to appearance quality. For example, it is preferable to have higher printability for oil-based inks in which the solvent is alcohol and contains pigments. In addition, it is preferable that the printed ink is difficult to peel off by wiping or transfer (that is, it has excellent printing adhesion). The adhesive film preferably has solvent resistance to such a degree that even if the printing is wiped with alcohol (for example, ethanol) when the printing is corrected or eliminated, the appearance will not change significantly.

The top coat preferably contains wax ester as a slip agent, so even if the surface of the top coat is not subjected to further peeling treatment (such as coating with a silicone release agent or a long-chain alkyl release agent, any suitable It can also achieve sufficient lubricity (for example, the above-mentioned preferable coefficient of friction) under the state of peeling off the treatment agent and drying it. Such a state in which no further peeling treatment is performed on the surface of the top coat is preferable in terms of preventing whitening caused by the peeling treatment agent (for example, whitening caused by storage under heating and humidifying conditions). It is also advantageous in terms of solvent resistance.

In addition to the substrate, the adhesive layer and the top coat, the adhesive film can also be implemented in the form of further including other layers. Examples of the arrangement of the "other layer" include: between the first surface (back) of the substrate and the top coat, between the second surface (front) of the substrate and the adhesive layer, and the like. The layer arranged between the back surface of the substrate and the top coating layer may be, for example, a layer containing an antistatic component (antistatic layer). The layer disposed between the front surface of the substrate and the adhesive layer may be, for example, an undercoat (fixed layer), an antistatic layer, etc., which improves the grip of the adhesive layer on the second surface. An antistatic layer can be arranged on the front surface of the substrate, a fixing layer is arranged on the antistatic layer, and an adhesive film composed of an adhesive layer is arranged on the antistatic layer.

≪≪Foldable device and rollable device≫≫ The adhesive film of the present invention is excellent in flexibility and transparency, so for example, it can be preferably used in a bendable device (a bendable device) or a foldable device (a foldable device) or a rollable device having a movable bending part. It is included in the device (rollable device). The adhesive film of the present invention is particularly excellent in flexibility and transparency, so it can be preferably provided in a foldable device (foldable device) or a rollable device (rollable device) that has been harder to apply so far.

The foldable device of the present invention includes the adhesive film of the present invention. The foldable device of the present invention may contain any suitable other members as long as it includes the adhesive film of the present invention.

The rollable device of the present invention includes the adhesive film of the present invention. The rollable device of the present invention may contain any suitable other members as long as it includes the adhesive film of the present invention.

Fig. 1 is a schematic cross-sectional view showing an embodiment of the foldable device of the present invention as a representative example of a use form of the adhesive film of the present invention. In FIG. 1, the foldable device 1000 of the present invention includes a cover film 10, an adhesive layer 20, a polarizing plate 30, an adhesive layer 40, a touch sensor 50, an adhesive layer 60, an OLED 70, and an OLED 70 of the present invention.粘膜100。 Adhesive film 100. The adhesive film 100 of the present invention includes an adhesive layer 80 and a substrate layer 90 in FIG. 1. The adhesive layer 20, the adhesive layer 40, and the adhesive layer 60 may be an adhesive layer containing an adhesive of the same composition as the adhesive layer 80 constituting the adhesive film 100 of the present invention, or may be an adhesive layer containing adhesives of different compositions Adhesive layer.

The adhesive film of the present invention is excellent in flexibility and transparency, so for example, it can be preferably used in a bendable device (a bendable device) or a foldable device (a foldable device) or a rollable device having a movable bending part. Equipped on the back of the device (rollable device) (opposite to the display surface). Fig. 1 is a diagram provided on the back of a foldable device (a foldable device) (opposite to the display surface). Example

Hereinafter, examples and comparative examples are given to explain the present invention more specifically. However, the present invention is not limited by these. In addition, in the following description, "parts" and "%" are based on weight unless otherwise specified.

＜tanδ＞ A viscoelasticity measuring device "RSA-G2" (manufactured by TA Instruments Japan Co., Ltd.) was used to measure the sample size with a width of 5 mm × a distance of 15 mm and an axial force of 100 g in the tensile mode. In the strain sweep (amplitude, Oscilation amplitude) mode, the frequency is 1 Hz, the measurement temperature is 90°C, and the immersion time is 60 seconds. The strain measurement area is set from 0.01% to 1.0%, and the strain measurement during the period is performed. Graph the value of tanδ under each strain, and calculate the tanδ of 0.1% strain and 0.7% strain from the graph. Regarding the thickness, for the storage modulus and loss elastic modulus of the adhesive film, the rigidity of the substrate is relatively large, and the influence of the adhesive can be ignored. Only the thickness of the substrate after the thickness of the adhesive is removed for measurement. tanδ is obtained by the following formula. tanδ=loss modulus of elasticity/storage modulus

彎曲，於該狀態下以聚矽氧處理隔離件之聚矽氧處理面夾持，於該態樣下固定，於90℃下保持48小時。其後，解除彎曲，於23℃、50%RH下放置24小時後，測定彎折之膜之角度。將完全恢復至原狀之情形設為180度，將以原樣維持最初固定時之彎折狀態之情形設為0度。<Bending test> The flat adhesive film is shown in Figure 2 with the adhesive layer as the outside, and the adhesive film is set to 6

Bend, clamp it with the silicone-treated surface of the silicone-treated spacer in this state, fix it in this state, and keep it at 90°C for 48 hours. After that, the bending was released, and after standing at 23°C and 50%RH for 24 hours, the angle of the bent film was measured. Set the fully restored state to 180 degrees, and set the state of maintaining the original bent state as it is to 0 degrees.

<Peeling evaluation> Paste the adhesive film on a PET film (manufactured by Toray, S10) with a thickness of 50 μm. As shown in Figure 3, bend it so that the adhesive film becomes the inside. After keeping it at 90°C for 48 hours, release the fixed state and visually Observe the peeling of the adhesive film from the PET film. The evaluation is based on the following criteria. ○: No peeling from the PET film was seen. ×: Peeling from the PET film can be seen.

＜Measurement of haze and total light transmittance＞ Use haze meter HM-150 (manufactured by Murakami Color Technology Research Institute Co., Ltd.), based on JIS-K-7136, by haze (%) = (Td/Tt) × 100 (Td: diffuse transmittance, Tt: Total light transmittance). In addition, the total light transmittance is measured based on JIS-K-7316.

＜Young’s Modulus＞ Cut the sample piece into a short strip with a width of 10 mm. Use a universal tensile and compression testing machine (Tensilon) at a temperature of 25°C to place the short strip sample in the length direction at a distance of 100 mm between the chucks. It is stretched and measured, and Young's modulus is obtained by the obtained SS (Strain-Strength) curve. As the measurement conditions, the stretching speed is 200 mm/min, and the chuck distance is 50 mm. The method to obtain Young's modulus from the S-S curve is: make a graph of the S-S curve, draw a tangent line (one-time formula) in the graph within the range of displacement of 1 mm to 2 mm, and obtain it from the slope of the tangent line.

＜Adhesion＞ The adhesive film was cut into a width of 25 mm and a length of 150 mm and used as a sample for evaluation. In an environment with a temperature of 23°C and a humidity of 50%RH, the surface of the adhesive layer of the evaluation sample was attached to a glass plate (manufactured by Matsunami Glass Industry Co., Ltd., trade name: Micro slide with a 2.0 kg roller and 1 round trip glass S). After aging for 30 minutes in an environment with a temperature of 23℃ and a humidity of 50%RH, use a universal tensile testing machine (manufactured by Minebea Co., Ltd., product name: TCM-1kNB) at a peeling angle of 180 degrees and a tensile speed of 300 mm/ Peel off in minutes and measure the adhesion.

＜Coatability＞ Count the number of uneven round shapes in the coated top coating (including antistatic layer). Make 2 sheets in A4 size and calculate the average number. Two or less were judged to be good, and three or more were judged to be bad. The uneven part of the round shape is caused by the thinning of the thickness of the top coat, which is the part where the appearance becomes the defect, and the part that repels the antistatic agent and cannot be applied at all is regarded as "repellent".

<Surface resistance value (for Example 8)> In Example 8, the layer on which the antistatic treatment layer was formed was measured with a volume resistance meter Model 152-1 152P-2P probe (manufactured by Trek Japan Co., Ltd.) at a voltage of 10 V.

<Surface resistivity (for Examples 9-17 and Comparative Examples 6-9> In Examples 9-17 and Comparative Examples 6-9, a resistivity meter (manufactured by Mitsubishi Chemical Analytech, "Hiresta UP MCP-HT450") was used to contact the non-attached surface of the adhesive layer of the adhesive film with the URS probe. The surface resistivity was measured under the conditions of an applied voltage of 100 V and a voltage application time of 10 seconds.

[Manufacturing Example 1]: Preparation of adhesive composition A As monomer components, 2-ethylhexyl acrylate (2EHA): 63 parts by weight, N-vinyl-2-pyrrolidone (NVP): 15 parts by weight, and methyl methacrylate (MMA): 9 parts by weight Parts, 2-hydroxyethyl acrylate (HEA): 13 parts by weight, 2,2'-azobisisobutyronitrile as polymerization initiator: 0.2 parts by weight, and ethyl acetate as polymerization solvent: 133 parts by weight Put into the separable flask, and stir for 1 hour while introducing nitrogen. After removing oxygen in the polymerization system in this way, the temperature was raised to 65°C and reacted for 10 hours, and then ethyl acetate was added to obtain a solution of acrylic polymer (a) with a solid content of 30% by weight. Next, to the acrylic polymer (a1) solution, an isocyanate-based crosslinking agent is added so as to be 1 part by weight in terms of solid content relative to 100 parts by weight of the acrylic polymer (a) (solid content) (Trade name "Takenate D110N", manufactured by Mitsui Chemicals Co., Ltd.), an adhesive composition A was prepared.

[Manufacturing Example 2]: Preparation of adhesive composition B Add 96.2 parts by weight of 2-ethylhexyl acrylate (2EHA) and 3.8 parts by weight of hydroxyethyl acrylate (HEA) to a four-necked flask equipped with a stirring blade, a thermometer, a nitrogen introduction tube, and a condenser, as a polymerization initiator. 0.2 parts by weight of 2,2'-azobisisobutyronitrile and 150 parts by weight of ethyl acetate. While slowly stirring, nitrogen was introduced, and the liquid temperature in the flask was kept at around 60°C. The polymerization reaction was carried out for 6 hours to prepare acrylic acid. Solution (40% by weight) of polymer (b). The weight average molecular weight of the acrylic polymer (b) is 540,000. Next, the acrylic polymer (b) solution (40% by weight) was diluted with ethyl acetate to 25% by weight, and 400 parts by weight of the solution (100 parts by weight of solid content) was added as the sixth trifunctional isocyanate compound 4 parts by weight (solid content 4 parts by weight) of isocyanurate of methylene diisocyanate (manufactured by Tosoh Corporation, Coronaate HX) as a crosslinking agent, dioctyltin dilaurate (manufactured by Tokyo Fine Chemical Corporation, EMBILIZER OL-1, 1% by weight ethyl acetate solution) 2 parts by weight (0.02 parts by weight of solid content) as a crosslinking catalyst, 3 parts by weight of acetone, mixed and stirred to prepare an adhesive composition B.

[Example 1] Prepare a commercially available release liner ("DIAFOIL MRF-38", manufactured by Mitsubishi Plastics Co., Ltd.). The adhesive composition A was applied to one surface of the release liner (release surface) so that the thickness after drying became 25 μm, and dried at 130°C for 3 minutes. In this way, an adhesive layer with a thickness of 25 μm containing the acrylic adhesive A corresponding to the adhesive composition A was formed on the release surface of the release liner. A polyimide-based substrate (trade name "Kapton", manufactured by TORAY-DUPONT Co., Ltd.) with a thickness of 50 μm was prepared as the substrate layer. The adhesive layer formed on the release liner is attached to one surface of the substrate layer. The release liner is left on the adhesive layer as it is, and is used to protect the surface (adhesive layer) of the adhesive layer. After passing the resulting structure through a laminating machine (0.3 MPa, speed 0.5 m/min) at 80°C once, it was aged in an oven at 50°C for 1 day. In this way, an adhesive film (1) is obtained. The results are shown in Table 1.

[Example 2] Except that a polyimide-based substrate (trade name "Upilex-50S", manufactured by Ube Industries Co., Ltd.) with a thickness of 50 μm was used as the substrate layer, the same procedure as in Example 1 was performed to obtain an adhesive film ( 2). The results are shown in Table 1.

[Example 3] Except that a polyimide-based substrate (trade name "Pixeo BP", manufactured by Kaneka Co., Ltd.) with a thickness of 50 μm was used as the substrate layer, the same procedure as in Example 1 was performed to obtain an adhesive film (3). The results are shown in Table 1.

[Example 4] Except that a polyimide-based substrate (trade name "Upilex-50RN", manufactured by Ube Industries Co., Ltd.) with a thickness of 50 μm was used as the substrate layer, the same procedure as in Example 1 was performed to obtain an adhesive film ( 4). The results are shown in Table 1.

[Example 5] In addition to using a 50 μm thick polyether ether ketone (PEEK)-based substrate (trade name "Shin-Etsu Sepla Film", non-stretched film and high crystallinity, manufactured by Shin-Etsu Polymer Co., Ltd.) as the substrate layer, In the same manner as in Example 1, an adhesive film (5) was obtained. The results are shown in Table 1.

[Example 6] Except that a polyimide-based substrate (trade name "Neopulim S100", manufactured by Mitsubishi Gas Chemical Co., Ltd.) with a thickness of 50 μm was used as the substrate layer, the same procedure as in Example 1 was carried out to obtain an adhesive film (6 ). The results are shown in Table 1.

[Example 7] Except for using a 25 μm-thick polyether ether ketone (PEEK)-based substrate (trade name "EXPEEK", manufactured by Kurabo) as the substrate layer, the same procedure as in Example 1 was performed to obtain an adhesive film (7). The results are shown in Table 1.

[Comparative Example 1] Except for using a 25 μm-thick polyester-based substrate (trade name "Lumirror S10", manufactured by Toray) as the substrate layer, the same procedure was performed as in Example 1, to obtain an adhesive film (C1). The results are shown in Table 1.

[Comparative Example 2] Except for using a polyester-based substrate (trade name "Lumirror S10", manufactured by Toray) with a thickness of 50 μm as the substrate layer, the same procedure as in Example 1 was carried out to obtain an adhesive film (C2). The results are shown in Table 1.

[Comparative Example 3] Except that the adhesive composition B was used instead of the adhesive composition A, and a polyester-based substrate (trade name "Lumirror S10", manufactured by Toray) with a thickness of 50 μm was used as the substrate layer, it was performed in the same manner as in Example 1. , Obtain an adhesive film (C3). The results are shown in Table 1.

[Comparative Example 4] Except for using the adhesive composition B instead of the adhesive composition A, the same procedure as in Example 6 was carried out to obtain an adhesive film (C4). The results are shown in Table 1.

[Comparative Example 5] Except for using the adhesive composition B instead of the adhesive composition A, the same procedure as in Example 7 was carried out to obtain an adhesive film (C5). The results are shown in Table 1.

[Table 1] Substrate layer Substrate layer thickness (μm) Adhesive composition Adhesive layer thickness (μm) Adhesion (N/25 mm) tanδ (0.7%) tanδ (0.1%) tanδ(0.7%)－tanδ(0.1%) Bend test (degree) Peel evaluation Young's modulus (Pa) Total light transmittance (%) Haze (%) Example 1 Polyimide series 50 A 25 twenty one 0.07 0.03 0.04 70 〇 2.5×10 ⁹ 40.1 8.5 Example 2 Polyimide series 50 A 25 twenty one 0.07 0.04 0.03 110 〇 7.5×10 ⁹ 24.0 3.5 Example 3 Polyimide series 50 A 25 twenty one 0.07 0.05 0.02 115 〇 4.3×10 ⁹ 61.7 11.0 Example 4 Polyimide series 50 A 25 twenty one 0.06 0.03 0.03 125 〇 3.3×10 ⁹ 65.5 5.3 Example 5 PEEK series 50 A 25 twenty one 0.04 0.03 0.01 130 〇 2.5×10 ⁹ 65.5 96.3 Example 6 Polyimide series 50 A 25 twenty one 0.05 0.04 0.01 160 〇 2.3×10 ⁹ 88.3 0.2 Example 7 PEEK series 25 A 25 twenty one 0.05 0.02 0.03 175 〇 3.3×10 ⁹ 83.4 2.6 Comparative example 1 Polyester series 25 A 25 twenty one 0.16 0.10 0.06 0 〇 3.3×10 ⁹ 87.5 3.5 Comparative example 2 Polyester series 50 A 25 twenty one 0.14 0.08 0.06 20 〇 3.3×10 ⁹ 86.7 5.7 Comparative example 3 Polyester series 50 B 25 0.1 - - - 20 × 3.3×10 ⁹ 86.7 5.7 Comparative example 4 Polyimide series 50 B 25 0.1 - - - 160 × 2.3×10 ⁹ 88.3 0.2 Comparative example 5 PEEK series 25 B 25 0.1 - - - 175 × 3.3×10 ⁹ 83.4 2.6

[Manufacturing Example 3]: Production of Antistatic Treatment Polyimide Film A Dilute 10 parts by weight of an antistatic agent (manufactured by Solvex, Microsolver RMd-142, with tin oxide and polyester resin as main components) with a mixed solvent containing 30 parts by weight of water and 70 parts by weight of methanol to prepare an antistatic agent Solution. Using a Meyer rod, the obtained antistatic agent solution was coated on a polyimide-based substrate (trade name "Kapton", manufactured by TORAY-DUPONT Co., Ltd.) with a thickness of 50 μm as a substrate, at 130 After drying for 1 minute at °C, the solvent was removed to form an antistatic layer (thickness: 0.2 μm), and an antistatic treated polyimide film A was obtained.

[Example 8] Except for using the antistatic treatment polyimide film A as the substrate, the same procedure as in Example 1 was carried out to obtain an adhesive film (8). The surface resistance value is 5×10 ⁶ Ω.

[Manufacturing Example 4]: Production of polyimide film B with top coating ＜Preparation of coating material B＞ Prepare a dispersion containing 25% by weight of polyester resin (binder) as a binder (product of Toyobo Co., Ltd., trade name "VYLONAL MD-1480" (water dispersion of saturated copolyester resin); also referred to as "Binder Dispersion"). In addition, an aqueous dispersion of carnauba wax (manufactured by Nippon Wax, trade name "refined carnauba wax No. 2 powder") as a slip agent (hereinafter also referred to as "slip agent dispersion") was prepared. Furthermore, an aqueous solution containing 0.5% by weight of poly(3,4-dioxythiophene) (PEDOT) as a conductive polymer and 0.8% by weight of polystyrene sulfonate (number average molecular weight 150,000) (PSS) was prepared ( Product of HC Stark, trade name "Baytron P"; hereinafter also referred to as "conductive polymer aqueous solution"). To a mixed solvent of water and ethanol (50:50 by weight), add 100 parts by weight of the above-mentioned binder dispersion based on the solid content and 30 parts by weight of the above-mentioned slip agent dispersion based on the solid content , 50 parts by weight of the above-mentioned conductive polymer aqueous solution and 7 parts by weight of the melamine-based crosslinking agent based on the solid content, stir for about 20 minutes, and mix well. In this way, coating material B with an NV of about 0.15% by weight was prepared. ＜Production of polyimide film B to form top coating＞ The above coating material B was applied to a 50 μm thick polyimide-based substrate (trade name "Kapton", manufactured by TORAY-DUPONT Co., Ltd.) as a base material with a bar coater at 130°C Heat for 2 minutes to dry. In this way, a substrate (polyimide film B for forming a top coating layer) with a transparent top coating layer having a thickness of 10 nm on one side of the polyimide-based substrate was fabricated.

[Manufacturing Example 5]: Production of polyimide film C with top coating ＜Preparation of coating material C＞ Prepare a polyester urethane containing 25 mol% ethylene glycol, 25 mol% neopentyl glycol, 30 mol% terephthalic acid, 10 mol% adipic acid and 10 mol% toluene diisocyanate as a binder 25% by weight aqueous solution of ester resin (hereinafter also referred to as "binder dispersion"). In addition, an aqueous dispersion of carnauba wax (manufactured by Nippon Wax, trade name "refined carnauba wax No. 2 powder") as a slip agent (hereinafter also referred to as "slip agent dispersion") was prepared. Furthermore, an aqueous solution containing 0.5% by weight of poly(3,4-dioxythiophene) (PEDOT) as a conductive polymer and 0.8% by weight of polystyrene sulfonate (number average molecular weight 150,000) (PSS) was prepared ( Product of HC Stark, trade name "Baytron P"; hereinafter also referred to as "conductive polymer aqueous solution"). Furthermore, an aqueous solution containing 10% by weight of polyethylene glycol (PEG) alkyl ether and 10% by weight of polyvinyl alcohol was prepared as a dispersant. To a mixed solvent of water and ethanol (50:50 by weight), add 40 parts by weight of the above-mentioned binder dispersion based on solid content and 5 parts by weight of the above-mentioned slip agent dispersion based on solid content. , 8 parts by weight of the above-mentioned conductive polymer aqueous solution, 40 parts by weight of the above-mentioned dispersant, and 7 parts by weight of the melamine-based crosslinking agent based on the solid content, stir for about 20 minutes, and mix well. In this way, the coating material C with an NV of about 0.30% by weight was prepared. ＜Production of polyimide film C forming the top coat＞ The above coating material C was applied to a 50 μm thick polyimide-based substrate (trade name "Kapton", manufactured by TORAY-DUPONT Co., Ltd.) as a base material with a bar coater at 130°C Heat for 2 minutes to dry. In this way, a base material (polyimide film C forming a top coat layer) having a transparent top coat with a thickness of 10 nm on one side of the polyimide base material was produced.

[Example 9] Except for using the polyimide film B for forming the top coat as the substrate, the same procedure was performed as in Example 1 to obtain an adhesive film (9). The results are shown in Table 2.

[Example 10] Except for using the polyimide film B for forming the top coat as the substrate, the same procedure was performed as in Example 2 to obtain an adhesive film (10). The results are shown in Table 2.

[Example 11] Except for using the polyimide film B for forming the top coat as the substrate, the same procedure was performed as in Example 4 to obtain an adhesive film (11). The results are shown in Table 2.

[Example 12] Except for using the polyimide film B for forming the top coat as the substrate, the same procedure was performed as in Example 7 to obtain an adhesive film (12). The results are shown in Table 2.

[Example 13] Except for using the polyimide film C forming the top coat layer as the substrate, the same procedure was performed as in Example 1 to obtain an adhesive film (13). The results are shown in Table 2.

[Example 14] Except for using the polyimide film C forming the top coat as the substrate, the same procedure was performed as in Example 2 to obtain an adhesive film (14). The results are shown in Table 2.

[Example 15] Except for using the polyimide film C forming the top coat as the substrate, the same procedure was performed as in Example 3 to obtain an adhesive film (15). The results are shown in Table 2.

[Example 16] Except for using the polyimide film C forming the top coat as the substrate, the same procedure was performed as in Example 4 to obtain an adhesive film (16). The results are shown in Table 2.

[Example 17] Except for using the polyimide film C forming the top coat as the substrate, the same procedure was performed as in Example 7 to obtain an adhesive film (17). The results are shown in Table 2.

[Comparative Example 6] Except for using the polyimide film B for forming the top coat as the base material, the same procedure was performed as in Comparative Example 1 to obtain an adhesive film (C6). The results are shown in Table 2.

[Comparative Example 7] Except for using the polyimide film B forming the top coat as the base material, the same procedure was performed as in Comparative Example 2 to obtain an adhesive film (C7). The results are shown in Table 2.

[Comparative Example 8] Except for using the polyimide film C forming the top coat as the base material, the same procedure as in Comparative Example 1 was performed to obtain an adhesive film (C8). The results are shown in Table 2.

[Comparative Example 9] Except for using the polyimide film C forming the top coat layer as the substrate, the same procedure was performed as in Comparative Example 2 to obtain an adhesive film (C9). The results are shown in Table 2.

[Table 2] Substrate layer Substrate layer thickness (μm) Coating material for forming top coat Top coat thickness (nm) tanδ (0.7%) tanδ (0.1%) tanδ(0.7%)－tanδ(0.1%) Bend test (degree) Coatability Surface resistivity (Ω) Example 9 Polyimide series 50 B 10 0.07 0.03 0.04 70 8.5 bad 1.42×10 ⁶ Example 10 Polyimide series 50 B 10 0.07 0.04 0.03 110 15 bad 2.84×10 ⁶ Example 11 Polyimide series 50 B 10 0.06 0.03 0.03 125 8.5 bad 2.35×10 ⁶ Example 12 PEEK series 25 B 10 0.05 0.02 0.03 175 5 bad 1.52×10 ⁶ Example 13 Polyimide series 50 C 50 0.07 0.03 0.04 70 1 good 5.73×10 ⁷ Example 14 Polyimide series 50 C 50 0.07 0.04 0.03 110 0 good 1.22×10 ⁷ Example 15 Polyimide series 50 C 50 0.07 0.05 0.02 115 0 good 1.26×10 ⁷ Example 16 Polyimide series 50 C 50 0.06 0.03 0.03 125 0 good 6.59×10 ⁷ Example 17 PEEK series 25 C 50 0.05 0.02 0.03 175 0 good 1.53×10 ⁷ Comparative example 6 Polyester series 25 B 10 0.16 0.10 0.06 0 0 good 1.06×10 ⁶ Comparative example 7 Polyester series 50 B 10 0.14 0.08 0.06 20 0 good 1.68×10 ⁶ Comparative example 8 Polyester series 25 C 50 0.16 0.10 0.06 0 0 good 2.77×10 ⁷ Comparative example 9 Polyester series 50 C 50 0.14 0.08 0.06 20 0 good 2.37×10 ⁷ [Industrial availability]

The adhesive film of the present invention is excellent in flexibility and transparency, so for example, it can be preferably used in a bendable device (a bendable device) or a foldable device (a foldable device) or a rollable device having a movable bending part. It is included in the device (rollable device).

玻璃棒 2:聚矽氧處理隔離件 3:接著劑層 4:固定玻璃 5:PET膜 10:覆蓋膜 20:黏著劑層 30:偏光板 40:黏著劑層 50:觸控感測器 60:黏著劑層 70:OLED 80:黏著劑層 90:基材層 100:黏著膜 1000:可摺疊式裝置1:6

Glass rod 2: Silicone treated spacer 3: Adhesive layer 4: Fixed glass 5: PET film 10: Cover film 20: Adhesive layer 30: Polarizing plate 40: Adhesive layer 50: Touch sensor 60: Adhesive layer 70: OLED 80: Adhesive layer 90: Substrate layer 100: Adhesive film 1000: Foldable device

Fig. 1 is a schematic cross-sectional view showing an embodiment of the foldable device of the present invention, and showing a use form of the adhesive film of the present invention. Fig. 2 is a schematic cross-sectional view illustrating the evaluation method of the bending reversibility. Fig. 3 is a schematic cross-sectional view illustrating the evaluation method of peeling evaluation.

10: Cover film

20: Adhesive layer

30: Polarizing plate

40: Adhesive layer

50: Touch sensor

60: Adhesive layer

70: OLED

80: Adhesive layer

90: substrate layer

100: Adhesive film

1000: Foldable device

Claims (20)

An adhesive film, which has a substrate layer and an adhesive layer, and The tanδ (0.7%) at a strain of 0.7% measured in the tensile mode of the viscoelasticity measuring device is 0.1 or less. An adhesive film, which has a substrate layer and an adhesive layer, and The difference between tanδ (0.7%) at a strain of 0.7% and tanδ (0.1%) at a strain of 0.1% (tanδ(0.7%)－tanδ(0.1%)) measured in the tensile mode of the viscoelasticity measuring device is 0.05 the following. Such as the adhesive film of claim 1 or 2, where 6

After bending and keeping it at 90°C for 48 hours, the bending is released, and the bending angle after being left at 23°C and 50%RH for 24 hours is 60 degrees to 180 degrees. The adhesive film according to any one of claims 1 to 3, wherein a top coat is provided on the surface of the substrate layer opposite to the surface having the adhesive layer. The adhesive film of claim 4, wherein the top coat layer contains an adhesive containing at least one selected from the group consisting of polyester resin and urethane resin. The adhesive film of claim 5, wherein the adhesive includes a urethane-based resin. The adhesive film according to any one of claims 4 to 6, wherein the top coating layer contains an antistatic component. The adhesive film of any one of claims 1 to 7, wherein the Young's modulus at 23° C. of the above-mentioned substrate layer is 6.0×10 ⁷ Pa or more. The adhesive film of claim 8, wherein the material of the substrate layer is at least one selected from polyimide and polyether ether ketone. The adhesive film according to any one of claims 1 to 3, wherein a top coat is provided on the surface of the substrate layer opposite to the surface having the adhesive layer, and the top coat contains a urethane-containing The binder and antistatic component of the resin, and the material of the substrate layer is at least one selected from polyimide and polyether ether ketone. For example, the adhesive film of any one of claims 1 to 10 has a total light transmittance of 20% or more. For example, the adhesive film of any one of claims 1 to 11 has a haze of 15% or less. Such as the adhesive film of any one of Claims 1 to 12, wherein the tensile speed of the adhesive layer at 23°C is 300 mm/min, and the adhesion to the SUS board under 180° peeling is 1 N/25 mm or more . The adhesive film according to any one of claims 1 to 13, wherein the adhesive layer contains an acrylic adhesive. Such as the adhesive film of any one of claims 1 to 14, which is attached to a foldable member. Such as the adhesive film of claim 15, wherein the foldable member is an OLED. Such as the adhesive film of any one of claims 1 to 16, which is attached to a rollable member. Such as the adhesive film of claim 17, wherein the rollable member is an OLED. A foldable device is provided with an adhesive film according to any one of claims 1 to 14. A rollable device is provided with an adhesive film as claimed in any one of claims 1 to 14.

Images