JP2012071549A - Laminated sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminated sheet that has superior cutting properties, can be easily cut in a desired shape with high accuracy even if having thickness more than a fixed amount, and also has superior arrangement properties.SOLUTION: A laminated sheet is made by laminating protective films on both sides of an elastic sheet containing a soft layer. In the laminated sheet, the soft layer has the thickness of ≥100 μm, and shore A hardness of 5-70, and the protective film has the thickness of ≥10 μm and ≤1,000 μm, and the storage elasticity modulus ≥0.1 GPas at 20 °C.

Description

The present invention relates to a laminated sheet. More specifically, the present invention relates to a laminated sheet that can be suitably used in various optical devices and the like.

In various optical devices such as liquid crystal displays and other display devices, various sheet-like members have been developed as adhesives for bonding optical members and parts, and as buffer materials interposed between optical members and parts. Yes. Such a sheet-like member is required to have appropriate softness in order to realize adhesive strength, vibration resistance, impact resistance, and the like. Conventionally, a protective film is often disposed on the surface of a sheet having flexibility (for example, an adhesive sheet) and transported, and the protective film is often cut into a desired size and shape during use. If the flexible sheet can be handled similarly in the optical application as described above, it is advantageous from the viewpoint of improving the handleability. However, in the optical application, it is particularly required that the sheet can be cut with high accuracy. In optical applications, it is also required that the cut sheet can be arranged with high accuracy while maintaining its shape. Therefore, there is a demand for a flexible sheet that can be precisely cut and arranged with high accuracy.

As a cushioning material interposed between the optical member / component, for example, a cushioning material intended to close a gap between a filter of a CRT display device or a liquid crystal display device and a cathode ray tube or a liquid crystal panel is disclosed ( For example, see Patent Document 1.) The main body of the cushion material is formed of silicon rubber, and a synthetic resin sheet and an adhesive layer are sequentially laminated on one surface thereof. A release layer is provided on the surface of the adhesive layer.

Japanese Patent Laid-Open No. 10-319854

As described above, various sheet-like members as cushioning materials and the like have been studied in optical applications. However, these conventional techniques have room for improvement in terms of facilitating high-precision cutting and placement. It was. In particular, when cutting a highly flexible sheet such as an adhesive sheet, when the thickness of the sheet exceeds a certain value (for example, 100 μm or more), it is possible to accurately cut the sheet into a tape shape (strip shape) or the like. It will not be easy. Further, as described above, a protective film is often disposed on the flexible sheet. In this case, since the sheet is cut together with the protective film, particularly excellent cutting characteristics are required. In addition, it is not easy to accurately place the cut flexible sheet while maintaining the shape (for example, linear shape). Thus, even if there is a certain thickness or more, it is possible to cut into a desired size and shape with high accuracy required in optical applications, and in order to obtain a flexible sheet having excellent arrangement characteristics. There was room for ingenuity.

The present invention has been made in view of the above-described situation, and has excellent cutting characteristics, can be easily cut into a desired shape with high accuracy even if it has a certain thickness or more, and has excellent layout characteristics. An object is to provide an excellent laminated sheet.

The inventor has studied various flexible sheets excellent in cutting characteristics and arrangement characteristics, and paid attention to the relationship between the cutting characteristics, the sheet hardness, and the protective film characteristics. And the lamination sheet formed by laminating | stacking the protective film of the specific thickness which has a specific elastic modulus on both surfaces of the elastic sheet containing the soft layer which has specific hardness (Shore A hardness) is a fixed thickness or more. It has been found that it has excellent cutting characteristics. Furthermore, it has also been found that such a laminated sheet has excellent arrangement characteristics that can be easily arranged while maintaining its shape with high accuracy. And it discovered that such a lamination sheet was very useful for an optical use, and came up with the present invention, conceiving that the said subject can be solved brilliantly.

That is, the present invention is a laminated sheet obtained by laminating protective films on both sides of an elastic sheet including a soft layer, and the soft layer has a thickness of 100 μm or more and a Shore A hardness of 5 to 70. The protective film is a laminated sheet having a thickness of 10 μm or more and 1000 μm or less, and a storage elastic modulus at 20 ° C. of 0.1 GPa or more.
The present invention is also a laminate obtained by cutting the laminate sheet into a strip shape.
The present invention is further a method for cutting the laminated sheet into an arbitrary shape, wherein the laminated sheet is cut by at least one method selected from the group consisting of laser cutting, punching, slitting and shearing. It is also a cutting method of the laminated sheet.
The present invention is described in detail below.

The elastic sheet constituting the laminated sheet of the present invention includes a soft layer. The soft layer has a Shore A hardness of 5 to 70. When the Shore A hardness is within the above range, the laminated sheet has moderate softness, and has excellent cutting characteristics and arrangement characteristics. The Shore A hardness is more preferably 60 or less, and still more preferably 50 or less. The Shore A hardness is also preferably 10 or more. The Shore A hardness is a value measured in an air atmosphere maintained at a constant temperature of 23 ° C.
The Shore A hardness can be confirmed by measuring the hardness after 15 seconds using an A-type durometer (rubber hardness meter, manufactured by Asker) based on JISK 6253. The sample shape is 100 mm wide x 20 mm deep x 6 mm thick.

The soft layer also has a thickness of 100 μm or more. When the thickness of the soft layer is within the above range, the excellent cutting characteristics and arrangement characteristics of the laminated sheet are remarkably exhibited. The thickness of the soft layer is preferably 200 μm or more, more preferably 300 μm or more, and still more preferably 400 μm or more. The thickness of the soft layer is also preferably 2000 μm or less, more preferably 1500 μm or less, and still more preferably 1000 μm or less.

The soft layer preferably has a storage elastic modulus at 20 ° C. of 1 × 10 ⁴ to 1 × 10 ⁷ Pa. More preferably, it is 5 * 10 < ⁴ > -8 * 10 < ⁶ > Pa, More preferably, it is 1 * 10 < ⁵ > -5 * 10 < ⁶ > Pa.
The storage elastic modulus can be measured using a dynamic viscoelasticity measuring device (RSA-III, manufactured by T.A. Instruments Inc.). Usually, it measures in the temperature range of -20 degreeC-100 degreeC. In the present invention, the storage elastic modulus at 20 ° C. is adopted.

Moreover, it is preferable that the said soft layer is what has adhesiveness. Specifically, the adhesive strength is preferably 5 g / 25 mm or more. More preferably, it is 10 g / 25 mm or more, More preferably, it is 20 g / 25 mm or more. The adhesive strength of the soft layer is also preferably 500 g / 25 mm or less. More preferably, it is 400 g / 25 mm or less, More preferably, it is 300 g / 25 mm or less. Adhesive strength is obtained by attaching a 25 mm width PET film (thickness 25 μm) to a sheet made of a soft layer in an air atmosphere maintained at a constant temperature of 23 ° C. , And can be measured as the adhesive strength when peeled in the 180 ° direction at a peeling speed of 300 mm / min.

The soft layer may have a single layer structure having a uniform composition or a multilayer structure in which layers having different compositions are laminated. What is to be the composition, that is, the characteristics of each layer in the multilayer structure (laminated structure) may be appropriately selected according to the purpose of use of the elastic sheet. When the elastic sheet is used as a bonding material for an optical transmission medium, the soft layer may have a multilayer structure of two or more layers having different refractive indexes, polarities, adhesive forces, etc., depending on the refractive index and material of the material to be connected. it can. In such a multilayer structure, it is preferable that at least one of the surfaces of the soft layer has the adhesive force described above. In general, a single-layer structure is recommended in that light transmission loss due to light scattering or reflection in the soft layer is suppressed.

As a material for forming the soft layer, organic resin materials such as (meth) acrylic resin, silicone resin, polyolefin resin, polyester resin, polyether resin, and polydiene resin can be used. Each of these may be used alone, in combination of two or more, or in a composite composition of two or more.
Among these, (meth) acrylic resin, silicone resin, polyester resin, polyether resin, and polydiene resin are preferable. A (meth) acrylic resin and a silicone resin are more preferable in that the resin itself can have adhesiveness.
The (meth) acrylic resin is not particularly limited as long as it exhibits the above-described physical properties. For example, a polymerizable composition containing a (meth) acrylate oligomer having a weight average molecular weight of 5,000 to 500,000 as an essential polymerization component is polymerized. It is preferable that it is resin obtained. More preferably, the (meth) acrylate oligomer having a weight average molecular weight of 5,000 to 500,000 and the (meth) acrylate monomer are essential polymerization components.
The polymerizable composition usually contains a polymerization initiator, particularly preferably a radical polymerization initiator. Moreover, it is preferable that the ratio of the essential polymerization component contained in the said polymeric composition is 80 mass% or more with respect to 100 mass% of polymerization components. More preferably, it is 90 mass% or more, More preferably, it is 95 mass% or more, Most preferably, it is 99 mass% or more.
The composition ratio ((meth) acrylate oligomer (A) / (meth) acrylate monomer (B)) between the (meth) acrylate oligomer and the (meth) acrylate monomer is 30/70 to 99 by mass ratio. / 1 is preferable. The composition ratio is more preferably 50/50 to 95/5, and still more preferably 60/40 to 90/10.
The weight average molecular weight can be measured by gel permeation chromatography (column: TSKgel SuperMultipore HZ-N 4.6 ^* 150, eluent: tetrahydrofuran, standard sample: TSK polystyrene standard).

The (meth) acrylate oligomer is not particularly limited as long as it is an oligomer having at least one (meth) acryloyl group in one molecule and having a weight average molecular weight of 5,000 to 500,000, but has a specific structure. A group (meth) acrylate oligomer is preferred. Specifically, the oligomer preferably has an aliphatic hydrocarbon group in the main chain and a non-hydrocarbon group in the main chain and / or side chain. Non-hydrocarbon groups include, for example, carbon and carbon atoms in the structure such as urethane bonds (—O—C (═O) —N (H) —) and ester bonds (—O—C (═O) —). The site has at least one atom other than hydrogen and does not contain a hydrocarbon in the structure.
Examples of the aliphatic (meth) acrylate oligomer having the above specific structure include a urethane skeleton (—O—C (═O) —N (H) —R having an aliphatic hydrocarbon group (R) and a urethane bond. -); An ester skeleton having an aliphatic hydrocarbon group (R) and an ester bond (-O-C (= O) -R-); an ether skeleton having an aliphatic hydrocarbon group (R) and an ether bond ( -OR-); one or more organic skeletons such as a carbonate skeleton (-O-C (= O) -O-R-) having an aliphatic hydrocarbon group (R) and a carbonate bond. And an oligomer having a (meth) acrylate (co) polymer skeleton composed of a (co) polymer of a (meth) acrylate monomer. The ether skeleton includes an oxyalkylene skeleton (—RO—) composed of an oxyalkylene group.
From the viewpoint of obtaining a molded article having appropriate tackiness and elasticity, the oligomer is preferably a polyfunctional oligomer having two or more (meth) acryloyl groups in one molecule.

As the (meth) acrylate monomer, a (meth) acrylate compound other than the (meth) acrylate oligomer having a weight average molecular weight of 5,000 to 500,000 can be used. In addition, the (meth) acrylate compound used as a raw material for the (meth) acrylate oligomer can also be used as the (meth) acrylate monomer.
As the (meth) acrylate monomer, any conventionally known monofunctional or polyfunctional (meth) acrylate monomer can be used, but it has excellent durability (light resistance, heat resistance, moisture resistance). To aliphatic (meth) acrylate monomers, more preferably aliphatic (meth) acrylate monomers having a specific structure. Specifically, a monomer having an aliphatic chain hydrocarbon group having 4 or more carbon atoms, a monomer having an aliphatic cyclic structure, a monomer having a heterocyclic structure, a neopentyl structure and / or an alkylene glycol structure (oxyalkylene chain). Monomer having a (meth) acryloyl group and another polar group in one molecule. More preferably, it is a monomer having a (meth) acryloyl group and another polar group in one molecule. Since such a monomer is excellent in compatibility with the (meth) acrylate oligomer (particularly, the aliphatic (meth) acrylate oligomer having the specific structure), the resulting optical sheet has excellent transparency. .

As a method for producing a soft layer made of the (meth) acrylic resin, the polymerizable composition is applied on a support, polymerized (cured), and then the cured product (sheet) is peeled from the substrate. Examples thereof include a method, a method of casting the polymerizable composition into a mold and curing the mold, and then releasing the cured product (mold molding method). Among these, it is preferable to employ a forming method by coating in that the soft layer can be easily formed into a sheet shape which is a preferable shape. A protective film is preferably used as the support.
The polymerization is preferably heat polymerization or polymerization with light such as ultraviolet rays, and a polymerization initiator may be appropriately selected according to the polymerization method and conditions.

Specifically, a condensation type silicone rubber or an addition type silicone rubber is preferably used as the silicone resin. Examples of the condensation type silicone rubber include YE3085, YE5505 (manufactured by Momentive Performance Materials), and KE-4666S (manufactured by Shin-Etsu Chemical Co., Ltd.). Examples of the addition type silicone rubber include IVS4632, TSE3250, TSE3032, TSE3033 (manufactured by Momentive Performance Materials), LPS-3412, KE-1871, KE-106, KE-1031 (manufactured by Shin-Etsu Chemical Co., Ltd.) and the like. Is done.

Moreover, what added components, such as a fine particle component, to the said organic resin material for the purpose of controlling a refractive index in the range which does not impair elasticity and adhesiveness is used suitably. Additive components include fine particles and fibers made of metal oxides that absorb little visible light such as silica, aluminum oxide, zirconium oxide, zinc oxide, titanium oxide, and indium oxide, and silicone resin particles such as polysilsesquioxane. Can be mentioned.

The elastic sheet may have a single layer structure composed of the soft layer, or may have a multilayer structure including the soft layer and a heterogeneous layer different from the soft layer. In the form in which the elastic sheet has a multilayer structure, it is preferable that a heterogeneous layer is provided on the surface of the soft layer. The heterogeneous layer is not particularly limited as long as it is a layer different from the soft layer, and may be appropriately selected according to the use of the elastic sheet. Specifically, for example, when the elastic sheet is used as a bonding material for an optical transmission medium, a material having a different refractive index, polarity, adhesive force, etc. is selected from the soft layer according to the refractive index and material of the material to be connected. Can be used. The thickness of the heterogeneous layer is preferably 500 μm or less. More preferably, it is 400 micrometers or less, More preferably, it is 300 micrometers or less. Moreover, it is preferable that it is 1 micrometer or more. The ratio of the thickness of the soft layer to the thickness of the heterogeneous layer (the thickness of the soft layer / the thickness of the heterogeneous layer) is preferably larger than 0.3. More preferably, it is larger than 0.5, and further preferably larger than 0.8. In particular, it is preferably larger than 1.

As the heterogeneous layer, for example, a (meth) acrylic polymer film or a thermoplastic resin film is preferably used because the laminated sheet of the present invention is further excellent in cutting processability and arrangement characteristics.
Examples of the (meth) acrylic polymer film include a polymerization component including at least one selected from the group consisting of a (meth) acrylate oligomer having a weight average molecular weight of less than 5000 and a (meth) acrylate monomer. A resin obtained by polymerizing the polymerizable composition is preferable. More preferably, the (meth) acrylate oligomer having a weight average molecular weight of less than 5000 and the (meth) acrylate monomer are essential polymerization components. The weight average molecular weight of the (meth) acrylate oligomer is more preferably less than 4000.
The polymerizable composition usually contains a polymerization initiator, particularly preferably a radical polymerization initiator.
Moreover, it is preferable that the ratio of the essential polymerization component contained in the said polymeric composition is 80 mass% or more with respect to 100 mass% of polymerization components. More preferably, it is 90 mass% or more, More preferably, it is 95 mass% or more, Most preferably, it is 99 mass% or more.
Moreover, it is preferable that the ratio of the said (meth) acrylate oligomer whose weight average molecular weight is less than 5000 is 50 mass% or more with respect to 100 mass% of essential polymerization components.

The (meth) acrylate oligomer is not particularly limited as long as it is an oligomer having at least one (meth) acryloyl group in one molecule and having a weight average molecular weight of less than 5,000, but an aliphatic having a specific structure. A (meth) acrylate oligomer is preferred. The specific form is the same as that described as the (meth) acrylate oligomer for forming the soft layer except for the range of the weight average molecular weight. The oligomer is preferably a polyfunctional oligomer having two or more (meth) acryloyl groups in one molecule.

As the (meth) acrylate monomer, a (meth) acrylate compound other than the (meth) acrylate oligomer having a weight average molecular weight of less than 5000 can be used. Preferably, an aliphatic (meth) acrylate monomer having a specific structure is used. The specific form is the same as that described as the (meth) acrylate monomer for forming the soft layer.

Examples of the thermoplastic resin film used for the heterogeneous layer include polyester resins such as PET and PEN; polyolefin resins such as polyethylene, polypropylene and polycycloolefin; polycarbonate resins; polyimide resins; PFA (perfluoroalkoxy fluororesin), FEP (four fluoropolymers). Fluorine resins such as ethylene / hexafluoropropylene copolymer resin) and ETFE (ethylene / chlorotrifluoroethylene copolymer resin) are preferred. In particular, polyester resin, polyolefin resin, polycarbonate resin, and polyimide resin are soft layers. It is preferable because of its excellent adhesion. In addition, those subjected to hydrophilic treatment such as corona treatment or plasma treatment are preferable in terms of excellent adhesion to the soft layer.

Although the manufacturing method of the elastic sheet by which a heterogeneous layer is laminated | stacked on a soft layer is not specifically limited, A preferable manufacturing method is demonstrated below.
The manufacturing method of the elastic sheet which uses a (meth) acrylic-type polymer film as a heterogeneous layer is not specifically limited. For example, by applying and polymerizing the polymerizable composition for forming the (meth) acrylic polymer film on the surface of the soft layer, the soft layer and the heterogeneous material comprising the (meth) acrylic polymer film on the surface thereof are polymerized. An elastic sheet in which a layer is formed can be obtained. The polymerization method and conditions for forming the (meth) acrylic polymer film are the same as those in the method for producing the soft layer.
As a method for producing an elastic sheet having a thermoplastic resin film as a heterogeneous layer, for example, a method of applying and polymerizing a polymerizable composition for forming a soft layer on the surface of a thermoplastic resin film to be a heterogeneous layer, The method of laminating a layer and a thermoplastic resin film is mentioned.

The elastic sheet preferably has a refractive index of 1.40 to 1.60 as a whole. When the refractive index is in such a range, the elastic sheet has a refractive index similar to that of acrylic resin (plate), glass, polycarbonate resin (plate), etc. used in the display device. Can be realized as a connected medium, high optical transmission efficiency can be realized. The refractive index of the elastic sheet is more preferably 1.45 to 1.55, and still more preferably 1.47 to 1.53.
The refractive index can be measured using a refractometer (Atago Co., Ltd., DR-M2).

The elastic sheet preferably has a visible light transmittance of 80% or more. Specifically, the parallel line transmittance at 400 nm is preferably 80% or more. As a result, it is possible to achieve high light transparency and transparency that are required particularly in applications to optical transmission bodies. The parallel line transmittance at 400 nm is more preferably 85% or more, and still more preferably 90% or more.
The transmittance can be measured using a sample having a thickness of 1 mm using a UV-VIS spectrophotometer (Agilent 8453, manufactured by Agilent Technologies).

Moreover, it is preferable that the said elastic sheet has heat resistance. Specifically, it is preferable that the parallel line transmittance at 400 nm of the elastic sheet after the heat resistance test, that is, after being held in an 85 ° C. heating furnace (atmosphere: air) for 1000 hours, is 75% or more. More preferably, it is 80% or more, More preferably, it is 85% or more.

Moreover, it is preferable that the said elastic sheet is what has light resistance. Specifically, after the light resistance test, that is, after the elastic sheet was placed in a metering weather meter (Muga, M6T, 100 mW / cm ² ) and subjected to the accelerated light resistance test for 100 hours, The parallel line transmittance at 400 nm of the sheet is preferably 75% or more. More preferably, it is 80% or more, More preferably, it is 85% or more.

It does not specifically limit as a manufacturing method of the said elastic sheet, A conventionally well-known method is employable. Specifically, as a method for forming the soft layer and the heterogeneous layer, a compression molding method, a casting method, an injection molding method, an extrusion molding method, a calendar molding method, a coating method such as a die coater / comma coater / lip coater, etc. Can do.
Further, in the form in which the elastic sheet has a multilayer structure of a soft layer and a heterogeneous layer, as a method of laminating each layer, lamination of the formed layers (laminate), insert molding, other on the formed layer Examples include direct coating of layers.

The laminated sheet of the present invention is formed by laminating protective films on both sides of the elastic sheet.
The elastic sheet is used in the state of a single layer structure or a laminated structure, for example, as a bonding layer constituting an optical transmission medium. However, since at least one surface is a surface of a soft layer, the elastic sheet is used as a form for bonding. When the surface (both sides) of the sheet is in a form protected with a protective film, the sheet is excellent in handleability.
The protective film has a thickness of 10 μm or more and 1000 μm or less, and a storage elastic modulus at 20 ° C. of 0.1 GPa or more. When the protective film has such characteristics, the laminated sheet has excellent cutting characteristics (cutting processability) and arrangement characteristics. The storage elastic modulus is preferably 1 GPa or more. The storage elastic modulus can be measured using a dynamic viscoelasticity measuring device (RSA-III, manufactured by TA Instruments). Usually, it measures in the temperature range of -20 degreeC-100 degreeC. In the present invention, the storage elastic modulus at 20 ° C. is adopted.

The protective film is preferably selected as appropriate according to the magnitude of the adhesive force on the elastic sheet surface. Usually, a surface having a high adhesive strength of 5 g / 25 mm or more (also referred to as a highly adhesive surface) is not subjected to a release-treated polymer film or in particular a release treatment or an adhesive treatment. A polymer film (also referred to as an untreated film) is preferably used.
Preferable specific examples of the polymer film subjected to the release treatment include release-treated PET films such as Panapeel TP series (manufactured by Panac Co., Ltd.), Unipeel TR series (manufactured by Unitika Ltd.), and the like.
Specific examples of the untreated film include PET such as Lumirror T60, Lumirror S10 (manufactured by Toray Industries), Teijin Tetron G2 and O3 (manufactured by Teijin DuPont Films), polyester such as PEN, polyethylene, polypropylene, and polycarbonate. Polymer films such as fluororesins such as PFA (perfluoroalkoxy fluororesin), FEP (tetrafluoroethylene / hexafluoropropylene copolymer resin), ETFE (ethylene / chlorotrifluoroethylene copolymer resin), etc. It is done. Among these, a polyester film is preferable, and a PET film is most preferable.
The thickness of the polymer film is not particularly limited as long as it is 10 μm or more and 1000 μm or less, but is preferably 50 μm or more from the viewpoint of easy control when it is cut, particularly processed into a half-cut state described later. More preferably, it is 75 micrometers or more, More preferably, it is 100 micrometers or more. On the other hand, 1000 μm or less is preferable, and 500 μm or less is more preferable from the viewpoint of excellent handleability.

On the other hand, as a protective film used for a surface having a low adhesive strength of less than 5 g / 25 mm (also referred to as a low adhesive surface), an adhesive layer is formed on the surface of the base film on the side in contact with the low adhesive surface. A polymer film (also referred to as an adhesion-treated film) having s is preferable.
As the base film, for example, polyethylene, polypropylene, polycarbonate, polyester and the like are preferable, among which polyester is preferable, and PET is particularly preferable.
As the adhesive layer, a self-adhesive layer (elastomer layer) and an acrylic adhesive layer are preferable, and an acrylic adhesive layer is more preferable.
Preferred examples of the polymer film having a self-adhesive layer include self-adhesive PET films such as Gel Poly series (manufactured by Panac Co., Ltd.) and CPETT series (manufactured by Oji Tac Co., Ltd.). Examples of polymer films having an acrylic adhesive layer include PET such as re-peeling film NT series, GN series, GS series (manufactured by Panac), heat-resistant re-peeling film CT series, HT series, ST series (manufactured by Panac). A film is preferably exemplified.
Although it will not specifically limit if it is 10 micrometers or more and 1000 micrometers or less as thickness of an adhesion processing film, From the point which is easy to cut, 50 micrometers or more are preferable. More preferably, it is 75 μm or more. On the other hand, it is preferably 1000 μm or less, more preferably 500 μm or less, and particularly preferably 200 μm or less from the viewpoint of excellent handleability.

Thus, it is one of the preferred embodiments of the present invention that the thickness of the protective film laminated on at least one surface of the elastic sheet is 50 μm or more.

In the form in which the elastic sheet has the multilayer structure described above, when the soft layer corresponds to a highly adhesive layer and the heterogeneous layer corresponds to a low adhesive layer, the surface of the soft layer (high adhesive surface) Is preferably formed by laminating the above-described release-treated film or untreated film as a protective film, and arranging the above-mentioned pressure-sensitive adhesive film on the heterogeneous layer surface (low-adhesive surface). When it is such a form, it is preferable that the adhesive force of the adhesive treatment film of the low adhesive surface side is lower than the adhesive force which the high adhesive layer in an elastic sheet has. By doing in this way, when peeling a protective film, delamination and delamination in an elastic sheet can be suppressed.
Moreover, it is preferable that the thickness of a mold release process film or an unprocessed film is 50 micrometers or more as mentioned above. Thus, in the form in which the elastic sheet includes the soft layer and the heterogeneous layer laminated on the surface thereof, the thickness of the protective film laminated on the surface of the elastic sheet on the soft layer side is 50 μm or more. This is one of the preferred embodiments of the present invention.
In addition, even when the elastic sheet does not include a heterogeneous layer and is composed of a soft layer in which two or more layers having different adhesive strengths are laminated, the above (when the heterogeneous layer is included) depends on the adhesive strength of the soft layer surface. It is preferable to select and laminate a protective film in the same manner as described above.

The production method of the laminated sheet of the present invention, that is, the elastic sheet provided with the protective film is not particularly limited. For example, a resin composition for an elastic sheet (usually a soft layer is formed on the surface of the first protective film). From a method of applying a second protective film to the non-contact surface side of the first protective film by a laminating process, or from a resin composition for an elastic sheet. Examples thereof include a method in which an elastic sheet is formed by mold polymerization or the like, and then adhered by laminating with both surfaces sandwiched between protective films. Although the above-mentioned curing is preferably both thermal curing and photocuring, photocuring is preferable from the viewpoint of excellent film thickness controllability. As light curing, ultraviolet curing is preferable.
In addition, when the elastic sheet has a multilayer structure, a sheet whose surface is protected by a protective film can be similarly produced. As a particularly preferable production method including the production of an elastic sheet having a multilayer structure composed of layers having different adhesive forces, the following method is employed.
Step 1) Resin for elastic sheet for forming a highly adhesive layer, preferably the above-mentioned highly adhesive layer, on the surface of the first protective film (the surface subjected to the mold release treatment in the case of the mold release treatment film). Apply and cure a composition (for example, a polymerizable composition for forming a soft layer, or a polymerizable composition for forming a soft layer (first layer) having high adhesion when the soft layer has a laminated structure) By doing so, a soft layer composed of a highly adhesive layer is formed on the surface of the first protective film.
Step 2) A composition for forming a heterogeneous layer having a lower adhesive strength than the layer, preferably a low-adhesion layer on the surface of the soft layer (for example, a polymerizable composition for forming a heterogeneous layer, or When the soft layer has a laminated structure, the surface of the first protective film is coated and cured by applying a polymerizable composition for forming a soft layer (second layer) whose adhesiveness is lower than that of the first layer. An elastic sheet having a multilayer structure is formed on the substrate.
Step 3) Lamination is performed in a state where the second protective film is laminated on the surface (lower adhesive surface) of the elastic sheet.
By the steps 1) to 3), a laminated sheet in which the elastic sheet is protected by the first protective film and the second protective film can be produced.
As a 1st protective film in the above-mentioned process 1), a mold release process or an untreated film is preferable, and as a 2nd protective film in the above-mentioned process 3), an adhesion processing film is preferable. However, as described above, the protective film is preferably selected based on the absolute value of the adhesive force, and the first protective film and the second protective film are both a release-treated or untreated film, or the first A form in which the protective film and the second protective film are both adhesive-treated films is also a suitable form.
The curing in the steps 1) and 2) is preferably both thermal curing and photocuring, but photocuring is preferable from the viewpoint of excellent film thickness controllability, and ultraviolet curing is preferable as photocuring.

Furthermore, the laminated sheet of the present invention is preferably cut into a width, length and shape necessary for use. Preferred examples of the cutting method include laser cutting, Thomson punching, slitting, and shearing. A method for cutting a laminated sheet into an arbitrary shape, wherein the laminated sheet is cut by at least one method selected from the group consisting of laser cutting, punching, slitting and shearing. The method is also one aspect of the present invention.

When the laminated sheet is cut, the laminated sheet may be cut into the necessary size and shape together with the protective film, but the following forms are preferred. That is, at least one surface of the elastic sheet cut into the required size and shape is provided with a protective film larger than the elastic sheet (the surface that can completely cover the surface of the elastic sheet and has an excess portion). It is preferable that the protective film is provided. In such a form, the protective film not only protects the surface of the elastic sheet, but also has a function as a support for supporting the elastic sheet. When the elastic sheet is supplied in such a form and used as, for example, a bonding material, the medium to be bonded can be bonded efficiently with high positional accuracy.
Furthermore, the protective film as the support is preferably in a half-cut state. The half-cut state refers to a state in which a protective film larger than the elastic sheet is cut by a part of the length in the thickness direction in accordance with the size and shape of the elastic sheet. In the protective film in such a state, the surplus portion when the surface of the elastic sheet is covered is not completely cut, so that the function as a support is maintained. By setting it as such a form, a protective film can be easily peeled from an elastic sheet at the time of use.
A more preferable form is that one of the protective films laminated on both sides of the elastic sheet and the elastic sheet are cut into a desired size and shape, and the other protective film is not cut, Or it is the form which is the state which has the function as a support body in the half cut state, ie, a support body. Particularly preferred is a form in which the other protective film is half cut. In this way, the elastic sheet and the protective film laminated on one surface thereof are cut into a predetermined size and shape, and the protective film laminated on the other surface (protective film as a support) is A form cut into a predetermined length and a predetermined length in the thickness direction from the surface in contact with the elastic sheet is one of the preferred embodiments in the present invention.
In addition, when one protective film is a release-treated film or an untreated film and the other protective film is an adhesive-treated film, the adhesive-treated film is cut into the same shape and size as the elastic sheet, and is subjected to a release treatment. The film or the untreated film is preferably in a form having a function as a support. Such a form is preferably employed when the elastic sheet has a multilayer structure. In the case of cutting, it is preferable to perform cutting from the adhesive-treated film side. A structure in which an elastic sheet is cut into a desired size and shape together with a protective film (adhesive film) on a half-cut protective film (release-treated film or untreated film) by cutting in this way. A sheet in which a plurality of laminates are supported and fixed is obtained. Thus, in the form in which the elastic sheet has a multilayer structure, a cutting method of a laminated sheet that is cut from the protective film side laminated on the surface of the soft layer is also one aspect of the present invention. Furthermore, a cutting method for a laminated sheet that is cut from the protective film side laminated on the surface of the soft layer, which is a cutting method for half-cutting the laminated sheet, is also one aspect of the present invention.

Since the laminated sheet of the present invention is composed of an elastic sheet having moderate flexibility, it can be suitably used for joining various members and parts. Especially, since the above-mentioned laminated sheet is excellent in cutting characteristics and arrangement characteristics, it is extremely useful for joining members and parts constituting various optical devices such as display devices in optical applications. In optical applications, it is preferable to use the laminated sheet by cutting it into a strip shape (tape shape). That is, a laminate obtained by cutting the laminate sheet into a strip shape is also one aspect of the present invention. And since the said laminated sheet can also be made into what has a high light transmittance and transparency, it is especially useful as a joining material for optical transmission bodies.

Since the molded body of the present invention has the above-described configuration, it has excellent cutting characteristics, and can be easily cut into a desired shape with high accuracy even if it has a certain thickness or more. It is possible to provide an excellent laminated sheet. Such a laminated sheet can be suitably used as a bonding material for an optical transmission body.

The present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to these examples. Unless otherwise specified, “part” means “part by weight” and “%” means “% by mass”.

<Synthesis of aliphatic (meth) acrylate oligomer>
Synthesis example 1
In a reactor equipped with a thermometer, a condenser, a nitrogen gas inlet tube and a stirrer, 208.6 parts of 2-ethylhexyl acrylate, 1.4 parts of 2-hydroxyethyl methacrylate, 0.21 n-dodecyl mercaptan as a chain transfer agent Then, 280.6 parts of ethyl acetate was charged as a solvent, and the reactor was replaced with nitrogen gas. Next, the internal temperature was raised to 85 ° C. while stirring the above mixture, and then 2,2′-azobis- (2-methylbutyronitrile) (trade name “ABN-E”; Japan as a polymerization initiator The reaction was started by adding 0.175 parts of hydrazine industry) and 3.15 parts of ethyl acetate as a solvent. 10 minutes after the start of polymerization, a mixture of 486.8 parts of 2-ethylhexyl acrylate, 3.2 parts of 2-hydroxyethyl methacrylate and 0.49 parts of n-dodecyl mercaptan as a chain transfer agent was added dropwise over 60 minutes from the dropping funnel. . Further, 0.175 part of ABN-E as a polymerization initiator and 14 parts of ethyl acetate as a solvent were similarly dropped from another dropping funnel. After completion of dropping, the dropping funnel was washed with 119 parts of ethyl acetate and added to the reactor. Then, after making it react at reflux temperature for 5 hours, it diluted with 105 parts of ethyl acetate, and obtained the solution of the acrylic polymer of 54% of non volatile matter density | concentration.
In a reactor equipped with a thermometer, a cooler, a nitrogen gas inlet tube and a stirrer, 100 parts of the above acrylic polymer solution in terms of solid content and 2,2′-methylenebis (4-methyl-6 as a polymerization inhibitor) -T-butylphenol) (trade name “ANTAGE W-400”; manufactured by Kawaguchi Chemical Co., Ltd.) 0.06 parts, 2-acryloyloxyethyl isocyanate (trade name “Karenz AOI”; manufactured by Showa Denko KK) 0.36 parts In addition, stirring was performed while bubbling a mixed gas of nitrogen / air = 2/1, and the internal temperature was raised to 70 ° C. Thereafter, 0.04 part of dibutyltin dilaurate was added as a catalyst and reacted at 70 ° C. for 3 hours, and then the disappearance of the 2273 cm ⁻¹ peak derived from the isocyanate group was confirmed by FT-IR analysis. The temperature was raised to 80 ° C., and the solvent was removed while stirring at 10 Torr for 3 hours to obtain an oligomer (a) having a weight average molecular weight of 291115.

<Preparation of Resin Composition for Elastic Sheet>
Preparation Example 1
CN9903 (aliphatic urethane acrylate oligomer, weight average molecular weight 3123, manufactured by Sartomer) 10 parts, UV-3000B (polyester urethane acrylate, weight average molecular weight 13365, manufactured by Nippon Synthetic Chemical Co., Ltd.) 50 parts, 2-ethylhexyl acrylate 20 parts, 20 parts of 2-hydroxylethyl acrylate and 1 part of IRGACURE 184 (manufactured by Ciba Japan) were weighed and mixed to obtain a resin composition (1).

Preparation Example 2
CN9893 (aliphatic urethane acrylate oligomer, weight average molecular weight 3123, manufactured by Sartomer) 70 parts, SR285 (tetrahydrofurfuryl acrylate, manufactured by Sartomer) 30 parts, IRGACURE 184 (manufactured by Ciba Japan Co.) 1 part was weighed and mixed. And a resin composition (2) was obtained.

Preparation Example 3
CN9893 (aliphatic urethane acrylate oligomer, weight average molecular weight 3123, manufactured by Sartomer) 70 parts, butyl acrylate 10 parts, 2-ethylhexyl acrylate 20 parts, IRGACURE 184 (manufactured by Ciba Japan Co., Ltd.) 1 part was weighed and mixed. A resin composition (3) was obtained.

Preparation Example 4
CN966H90 (polyester urethane acrylate 90% / ethoxyethoxyethyl acrylate 10%, manufactured by Sartomer) 80 parts, 2-hydroxylethyl acrylate 10 parts, SR256 (2- (2-ethoxyethoxy) ethyl acrylate (also known as ethyl carbitol acrylate)) 10 parts of Sartomer) and 1 part of IRGACURE 184 (Ciba Japan) were weighed and mixed to obtain a resin composition (4).

Preparation Example 5
70 parts of the oligomer (a) obtained in Synthesis Example 1, 10 parts of 2-ethylhexyl acrylate, 20 parts of SR256 (2- (2-ethoxyethoxy) ethyl acrylate (also known as ethyl carbitol acrylate), manufactured by Sartomer), IRGACURE 184 ( 1 part of Ciba Japan Co., Ltd.) was weighed and mixed to obtain a resin composition (5).

Example 1 (Example using an elastic sheet having a single-layer structure)
(Production of laminated sheet)
The resin composition (1) prepared in Preparation Example 1 was applied to a PET film (Lumirror T60, thickness 100 μm, manufactured by Toray Industries, Inc.) as a first protective film, and UV was applied using a high-pressure mercury lamp (USHIO INC.). Irradiation (irradiation amount: 500 mJ / cm ² ) gave an elastic sheet composed of a soft layer having a thickness of 400 μm. Next, a second protective film / elastic sheet is obtained by laminating a PET film (Lumirror T60, thickness 100 μm, manufactured by Toray Industries, Inc.) as a second protective film on the surface of the soft layer. A sheet (1) laminated in the order of (soft layer) / first protective film was obtained. Each physical property of the sheet (1) was measured by the method described later. The results are shown in Table 1.
(Cutting of laminated sheets)
Sheet (1) was cut as follows. That is, the sheet (1) is formed into a tape shape having a width of 5.0 mm by a Thomson punching method (a punching method using a punching blade in which 10 straight blades are arranged in parallel at intervals of 5.0 mm). Cutting was performed from the protective film side.
As a result of confirming a cross section perpendicular to the longitudinal direction of the obtained sheet with a micrometer, the second protective film and the elastic sheet (soft layer) are all cut to a width of 4.95 to 5.05 mm. The first protective film was cut to a thickness of 20 μm on the soft layer contact side. That is, the cut sheet is supported on a half-cut protective film (support) in a state where a large number of elastic sheets (with a protective film) cut into a tape shape having a width of 5.00 mm are arranged in the longitudinal direction. It was confirmed that it was fixed.

Example 2 (Example using an elastic sheet having a two-layer structure)
(Production of laminated sheet)
The resin composition (1) prepared in Preparation Example 1 was applied to a PET film (Lumirror T60, thickness 100 μm, manufactured by Toray Industries, Inc.) as a first protective film, and UV was applied using a high-pressure mercury lamp (USHIO INC.). Irradiation (irradiation amount: 500 mJ / cm ² ) gave a layer (a) (soft layer) having a thickness of 400 μm. Further, the resin composition (2) obtained in Preparation Example 2 was cured under the same conditions, and a layer (b) (heterogeneous layer) having a thickness of 400 μm was formed on the surface of the layer (a). A sheet was obtained. Next, laminating is performed in a state where the acrylic adhesive layer side of the acrylic adhesive-treated PET film (removable film GN75, thickness 75 μm, manufactured by Panac) as the second protective film is laminated on the surface of the layer (b). Thus, a sheet (2) laminated in the order of the second protective film / elastic sheet (layer (b) / layer (a)) / first protective film was obtained. Each physical property of the sheet (2) was measured by the method described later. The results are shown in Table 1.
(Cutting of laminated sheets)
Sheet (2) was cut in the same manner as in Example 1.
As a result of confirming a cross section perpendicular to the longitudinal direction of the obtained sheet with a micrometer, the second protective film and the elastic sheet (layer (b) / layer (a)) were all 4.95 to 5.05 mm. The first protective film was cut to a thickness of 20 μm on the contact side of the layer (a). That is, the cut sheet is supported on a half-cut protective film (support) in a state where a large number of elastic sheets (with a protective film) cut into a tape shape having a width of 5.00 mm are arranged in the longitudinal direction. It was confirmed that it was fixed.

Example 3 (Example using an elastic sheet having a single layer structure)
(Production of laminated sheet)
The resin composition (3) prepared in Preparation Example 3 was applied to a PET film (Lumirror T60, thickness 100 μm, manufactured by Toray Industries, Inc.) as a first protective film, and UV was applied using a high-pressure mercury lamp (USHIO Inc.). Irradiation (irradiation amount: 500 mJ / cm ² ) gave an elastic sheet composed of a soft layer having a thickness of 600 μm. Next, by laminating in the state where a PET film (ST-75, thickness 75 μm, manufactured by Panac Co.) having an acrylic adhesive layer as a second protective film was laminated on the surface of the soft layer, the second treatment was performed. A sheet (3) laminated in the order of protective film / elastic sheet (soft layer) / first protective film was obtained. Each physical property of the sheet (3) was measured by the method described later. The results are shown in Table 1.
(Cutting of laminated sheets)
Sheet (3) was cut in the same manner as in Example 1.
As a result of confirming a cross section perpendicular to the longitudinal direction of the obtained sheet with a micrometer, the second protective film and the elastic sheet (soft layer) are all cut to a width of 4.95 to 5.05 mm. The first protective film was cut to a thickness of 20 μm on the soft layer contact side. That is, the cut sheet is supported on a half-cut protective film (support) in a state where a large number of elastic sheets (with a protective film) cut into a tape shape having a width of 5.00 mm are arranged in the longitudinal direction. It was confirmed that it was fixed.

Example 4 (Example using an elastic sheet having a single layer structure)
(Production of laminated sheet)
The resin composition (4) prepared in Preparation Example 4 was applied to a PET film (Lumirror T60, thickness 100 μm, manufactured by Toray Industries, Inc.) as a first protective film, and UV was applied using a high-pressure mercury lamp (USHIO INC.). Irradiation (irradiation amount: 500 mJ / cm ² ) gave an elastic sheet composed of a soft layer having a thickness of 400 μm. Next, a second protective treatment is performed by laminating the release layer PET film (Panapeel TP-01, thickness 75 μm, manufactured by Panac) as a second protective film on the surface of the soft layer. A sheet (4) laminated in the order of film / elastic sheet (soft layer) / first protective film was obtained. Each physical property of the sheet (4) was measured by the method described later. The results are shown in Table 1.
(Cutting of laminated sheets)
Sheet (4) was cut in the same manner as in Example 1.
As a result of confirming a cross section perpendicular to the longitudinal direction of the obtained sheet with a micrometer, the second protective film and the elastic sheet (soft layer) are all cut to a width of 4.95 to 5.05 mm. The first protective film was cut to a thickness of 20 μm on the soft layer contact side. That is, the cut sheet is supported on a half-cut protective film (support) in a state where a large number of elastic sheets (with a protective film) cut into a tape shape having a width of 5.00 mm are arranged in the longitudinal direction. It was confirmed that it was fixed.

Example 5 (Example using single-layer elastic sheet)
(Production of laminated sheet)
The resin composition (5) prepared in Preparation Example 5 was applied to a release-treated PET film (Panapeel TP-01, thickness 75 μm, manufactured by Panac) as a first protective film, and a high-pressure mercury lamp (USHIO Inc.) Made by UV irradiation (irradiation amount: 500 mJ / cm ² ) to obtain an elastic sheet made of a soft layer having a thickness of 250 μm. Next, a second protective treatment is performed by laminating the release layer PET film (Panapeel TP-01, thickness 75 μm, manufactured by Panac) as a second protective film on the surface of the soft layer. A sheet (5) laminated in the order of film / elastic sheet (soft layer) / first protective film was obtained. Each physical property of the sheet (5) was measured by the method described later. The results are shown in Table 1.
(Cutting of laminated sheets)
The sheet (5) was cut in the same manner as in Example 1.
As a result of confirming a cross section perpendicular to the longitudinal direction of the obtained sheet with a micrometer, the second protective film and the elastic sheet (soft layer) are all cut to a width of 4.95 to 5.05 mm. The first protective film was cut to a thickness of 20 μm on the soft layer contact side. That is, the cut sheet is supported on a half-cut protective film (support) in a state where a large number of elastic sheets (with a protective film) cut into a tape shape having a width of 5.00 mm are arranged in the longitudinal direction. It was confirmed that it was fixed.

Comparative Example 1
(Production of laminated sheet)
The resin composition (1) prepared in Preparation Example 1 was applied to a PET film (Lumirror T60, thickness 100 μm, manufactured by Toray Industries, Inc.) as a first protective film, and UV was applied using a high-pressure mercury lamp (USHIO INC.). Irradiated (irradiation amount: 500 mJ / cm ² ) to obtain a sheet (c1) in which a first protective film was laminated on one side of an elastic sheet composed of a soft layer having a thickness of 400 μm. Each physical property of the sheet (c1) was measured by the method described later. The results are shown in Table 1. (Cutting of laminated sheets)
The sheet (c1) was cut in the same manner as in Example 1.
As a result of confirming a cross section perpendicular to the longitudinal direction of the obtained sheet with a micrometer, the elastic sheet (soft layer) was cut to a width of 5 mm, and the first protective film had a thickness on the soft layer contact side. It was cut to 20 μm.

The Shore A hardness, storage elastic modulus, refractive index, transparency, heat resistance, light resistance and adhesive strength of the sheets (1) to (5) and the sheet (c1) obtained in Examples 1 to 5 and Comparative Example 1 above. The measuring method is as follows.
In addition, in the storage elastic modulus, transparency, heat resistance, light resistance test, and adhesive strength evaluation, a 1 mm thick sheet obtained by casting between two glass plates with a 1 mm spacer was used. In the sheet (2) obtained in Example 2, the elastic sheet is composed of two layers, the above-mentioned sheet having a thickness of 1 mm was prepared for each layer constituting the elastic sheet, and used as the evaluation sheet.

<Shore A hardness>
Under an air atmosphere maintained at a constant temperature of 23 ° C., the hardness after 15 seconds was measured using an A-type durometer (rubber hardness meter, manufactured by Asker) based on JISK 6253. The sample shape was 100 mm wide x 20 mm deep x 6 mm thick.

<Storage modulus>
The value at 20 ° C. was measured using a dynamic viscoelasticity measuring device (RSA-III, manufactured by TA Instruments Inc.).

<Refractive index>
Measurement was performed using a refractometer (DR-M2 manufactured by Atago Co., Ltd.).

<Transparency>
Using a UV-VIS spectrophotometer (Agilent 8453, manufactured by Agilent Technologies), the parallel line transmittance at 400 nm was measured and evaluated. A film having a parallel line transmittance of 80% or more at 400 nm was evaluated as ◯.

<Heat resistance>
A heat resistance test was conducted for 1000 hours in an 85 ° C. heating furnace (atmosphere: air), the parallel line transmittance at 400 nm of the sheet after the test was measured, and evaluated according to the following criteria.
○: Parallel line transmittance is 80% or more Δ: 75% or more and less than 80% ×: less than 75%

<Light resistance>
The sheet for evaluation was placed in a metering weather meter (Made by Suga Test Instruments Co., Ltd., M6T, 100 mW / cm ² ), and after performing a 100-hour accelerated light resistance test, the parallel line transmittance at 400 nm of the sheet was measured. Evaluation was made according to the following criteria.
○: Parallel line transmittance is 80% or more Δ: 75% or more and less than 80% ×: less than 75%

<Adhesive strength>
A 25 mm wide PET film (thickness: 25 μm) was attached to the evaluation sheet, and was subjected to one reciprocal pressure bonding with a 2 kg roller. The adhesive force when peeled in the 180 ° direction at a peeling speed of 300 mm / min within 1 minute after the pressure bonding was measured. These measurements were performed in an air atmosphere maintained at a constant temperature of 23 ° C.

The cutting characteristics of the sheets obtained by cutting the sheets (1) to (5) and the sheet (c1) obtained in Examples 1 to 5 and Comparative Example 1 were evaluated by the following methods.
<Cutting characteristics evaluation>
About the cutting process sheet | seat obtained in each Example, the cutting surface was observed from the direction perpendicular | vertical to the width | variety of a tape.

The evaluation results of cutting characteristics are shown below.
Examples 1-5: It was flat with respect to the width direction of a tape.
Comparative Example 1: It was not flat with respect to the width direction of the tape, but the cut portion was raised, and the central portion in the width direction of the tape was a part of the arc.
In addition, about Examples 1-5, it is the result which peeled the 2nd protective film and confirmed the surface of the elastic sheet.

Claims (7)

A laminated sheet obtained by laminating protective films on both sides of an elastic sheet including a soft layer,
The soft layer has a thickness of 100 μm or more and a Shore A hardness of 5 to 70,
The protective film has a thickness of 10 μm or more and 1000 μm or less, and a storage elastic modulus at 20 ° C. of 0.1 GPa or more. The laminated sheet according to claim 1, wherein the thickness of the protective film laminated on at least one surface of the elastic sheet is 50 μm or more. The laminated sheet according to claim 1, wherein the elastic sheet further includes a heterogeneous layer laminated on the surface of the soft layer and different from the soft layer. The laminated sheet according to claim 3, wherein a thickness of the protective film laminated on the surface of the elastic sheet on the soft layer side is 50 μm or more. The elastic sheet and the protective film laminated on one surface thereof are cut into a predetermined size and shape, and the protective film laminated on the other surface has a predetermined length in the thickness direction from the surface in contact with the elastic sheet. The laminated sheet according to any one of claims 1 to 4, wherein the laminated sheet is cut into the predetermined size and shape. The laminated body obtained by cutting the laminated sheet in any one of Claims 1-4 in strip shape. A method for cutting the laminated sheet according to any one of claims 1 to 4 into an arbitrary shape, wherein the laminated sheet is obtained by at least one method selected from the group consisting of laser cutting, punching, slitting and shearing. A method for cutting a laminated sheet, characterized by cutting.