Wound film equipped with adhesive layer

Abstract

Provided is a method for producing a wound film equipped with an adhesive layer without a release liner, the method enabling a great length of winding while suppressing air bubble entrapment and wrinkles and also suppressing dents. Provided is a wound film equipped with an adhesive layer without a release liner, the wound film being such that air bubble entrapment and wrinkles are suppressed and dents are also suppressed.　In a method for producing a long wound film equipped with an adhesive layer: the film equipped with an adhesive layer has a release layer, a specific base material, and a specific adhesive layer in the stated order; the film equipped with an adhesive layer is wound around a winding shaft through use of a touch roll disposed in front of the winding shaft to form a wound film; and the touch pressure P of the touch roll satisfies 3.6 N / cm < P < 14.0 N / cm as linear pressure.

Description

Roll of film with adhesive layer

[0001] The present invention relates to a roll of a film with a pressure-sensitive adhesive layer.

[0002] In the manufacturing process of optical and electronic components, a surface protective film (SPV) is usually attached to the surface of the component to prevent scratches on the surface during processing, assembly, inspection, transportation, and the like.

[0003] A surface protection film typically has a laminated structure having a substrate and a pressure-sensitive adhesive layer. Conventionally, a surface protection film typically has a release liner provided on the exposed surface of the pressure-sensitive adhesive layer. Many surface protection films having a substrate, a pressure-sensitive adhesive layer, and a release liner in this order have been reported.

[0004] On the other hand, for reasons such as reducing the cost of release liners, there has recently been a demand for surface protection films that do not have a release liner on the exposed side of the pressure-sensitive adhesive layer. As such a surface protection film, a surface protection film in which a polyethylene film and a pressure-sensitive adhesive layer are laminated has been reported (Patent Document 1). This surface protection film is produced by extrusion molding, and by embossing the back surface of the polyethylene film, it can be wound and unwound without a release liner, and can be provided as a roll.

[0005] However, polyethylene-based films tend to contain clumps of resin that are not completely melted (fish eyes), which reduces inspectability during the manufacturing process of optical and electronic components and leads to problems such as a deterioration in product quality.Furthermore, because the back surface of the polyethylene-based film is embossed, there is a problem that dents are formed on the adherend during lamination.

[0006] Recently, a surface protection film has been reported that does not have a release liner and does not use a polyethylene film as a substrate, and that can be wound up and unwound without a release liner (Patent Document 2).

[0007] Japanese Patent Application Laid-Open No. 06-033022 Japanese Patent Application Laid-Open No. 2022-112659

[0008] A surface protection film without a release liner is wound up with the substrate and the pressure-sensitive adhesive layer directly overlapping each other. For this reason, surface protection films without a release liner are technically very difficult to wind up, and winding long lengths is particularly difficult, with the problem of air bubbles being easily trapped and wrinkles being easily formed. Furthermore, reducing the thickness of the pressure-sensitive adhesive layer to about 1 μm tends to make winding easier, but on the other hand, there is the problem of dents caused by foreign matter and the like occurring. On the other hand, increasing the thickness of the pressure-sensitive adhesive layer makes it less likely that dents caused by foreign matter and the like will occur, but winding long lengths becomes more difficult.

[0009] An object of the present invention is to provide a method for producing a roll of a pressure-sensitive adhesive layer-attached film without a release liner, which method enables long winding while suppressing the entrapment of air bubbles, the occurrence of wrinkles, and the formation of dents. Another object of the present invention is to provide a roll of a pressure-sensitive adhesive layer-attached film that can be produced by such a production method, in which the entrapment of air bubbles, the occurrence of wrinkles, and the formation of dents are suppressed.

[0010] [1] A method for producing a roll of a pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention is a method for producing a roll from a long length of pressure-sensitive adhesive layer-attached film, the pressure-sensitive adhesive layer-attached film having a release layer, a base material, and a pressure-sensitive adhesive layer in this order, the release layer and the pressure-sensitive adhesive layer being the outermost layers of the pressure-sensitive adhesive layer-attached film, the base material containing a polyester-based resin, the pressure-sensitive adhesive layer being a urethane-based pressure-sensitive adhesive layer composed of a urethane-based pressure-sensitive adhesive, the pressure-sensitive adhesive layer having a thickness of 4.0 μm to 10.0 μm, the pressure-sensitive adhesive layer-attached film being wound around a winding shaft via a touch roll arranged in front of the winding shaft to form a roll, and the touch pressure P of the touch roll being 3.6 N / cm<P<14.0 N / cm in terms of linear pressure. [2] In the method for producing a roll of a pressure-sensitive adhesive layer-attached film according to the above [1], the touch pressure P of the touch roll may be 4.3 N / cm<P<10.0 N / cm in terms of linear pressure. [3] In the method for producing a roll of a pressure-sensitive adhesive layer-attached film according to the above-mentioned [1] or [2], the product of the thickness D of the base material and the touch pressure P may be 0.018 N < (D × P) < 0.050 N. [4] In the method for producing a roll of a pressure-sensitive adhesive layer-attached film according to any one of the above-mentioned [1] to [3], the surface hardness S of the touch roll may be 30° < S < 80°. [5] In the method for producing a roll of a pressure-sensitive adhesive layer-attached film according to any one of the above-mentioned [1] to [4], the winding tension T of the pressure-sensitive adhesive layer-attached film on the winding shaft may be 200 N / m < T < 400 N / m. [6] In the method for producing a roll of a pressure-sensitive adhesive layer-attached film according to any one of [1] to [5] above, the low-speed peel strength of the pressure-sensitive adhesive layer from the release layer, measured at a peel speed of 0.3 m / min and a peel angle of 180° at a temperature of 23°C and a humidity of 50% RH, may be less than 0.01 N / 25 mm. [7] In the method for producing a roll of a pressure-sensitive adhesive layer-attached film according to any one of [1] to [6] above, the high-speed peel strength of the pressure-sensitive adhesive layer from the release layer, measured at a peel speed of 30 m / min and a peel angle of 180° at a temperature of 23°C and a humidity of 50% RH, may be less than 0.15 N / 25 mm. [8] In the method for producing a roll of a pressure-sensitive adhesive layer-attached film according to any one of [1] to [7] above, the roll length of the roll may be 3000 m or more.[9] A roll of a pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention is a roll of a long pressure-sensitive adhesive layer-attached film, the pressure-sensitive adhesive layer-attached film having a release layer, a base material, and a pressure-sensitive adhesive layer in this order, the release layer and the pressure-sensitive adhesive layer being the outermost layers of the pressure-sensitive adhesive layer-attached film, the base material containing a polyester-based resin, the pressure-sensitive adhesive layer being a urethane-based pressure-sensitive adhesive layer composed of a urethane-based pressure-sensitive adhesive, the pressure-sensitive adhesive layer having a thickness of 4.0 μm to 10.0 μm, and the low-speed peel strength of the pressure-sensitive adhesive layer from the release layer measured at a temperature of 23° C. and a humidity of 50% RH at a peel speed of 0.3 m / min and a peel angle of 180° is less than 0.01 N / 25 mm.

[10] In the roll of the pressure-sensitive adhesive layer-attached film according to the above [9], the high-speed peel strength of the pressure-sensitive adhesive layer from the release layer, measured at a peel speed of 30 m / min and a peel angle of 180 degrees, may be less than 0.15 N / 25 mm at a temperature of 23° C. and a humidity of 50% RH.

[11] In the roll of the pressure-sensitive adhesive layer-attached film according to the above [9] or

[10] , the roll length may be 3,000 m or more.

[0011] According to the present invention, it is possible to provide a method for producing a roll of a pressure-sensitive adhesive layer-attached film without a release liner, which method enables long winding while suppressing the entrapment of air bubbles and the occurrence of wrinkles and the formation of dents. According to the present invention, it is also possible to provide a roll of a pressure-sensitive adhesive layer-attached film that can be produced by such a production method, in which the entrapment of air bubbles and the occurrence of wrinkles and the formation of dents are suppressed.

[0012] FIG. 1 is a schematic explanatory view of one embodiment of a winding device that can be used in a method for producing a roll of a pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention.

[0013] When the expression "weight" appears in this specification, it may be read as "mass," which is commonly used as an SI unit indicating weight.

[0014] <<1. Pressure-sensitive adhesive layer-attached film>> A method for producing a roll of a pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention is a method for producing a roll from a long length of pressure-sensitive adhesive layer-attached film.

[0015] The pressure-sensitive adhesive layer-attached film has a release layer, a substrate, and a pressure-sensitive adhesive layer in this order. In the pressure-sensitive adhesive layer-attached film, the release layer and the pressure-sensitive adhesive layer are the outermost layers of the pressure-sensitive adhesive layer-attached film. The pressure-sensitive adhesive layer-attached film has a release layer, a substrate, and a pressure-sensitive adhesive layer in this order, and as long as the release layer and the pressure-sensitive adhesive layer are the outermost layers of the pressure-sensitive adhesive layer-attached film, any appropriate other layer may be included as long as the effects of the present invention are not impaired.

[0016] Since the pressure-sensitive adhesive layer-attached film does not have a separator on the side of the pressure-sensitive adhesive layer opposite the substrate, the cost of the separator can be reduced and the separator peeling step can be omitted.

[0017] The pressure-sensitive adhesive layer-attached film can be used for various applications, such as a surface protection film for protecting the surface of an optical component or an electronic component (e.g., glass, polarizing plate, wavelength plate, retardation plate, optical compensation film, reflective sheet, brightness enhancement film, transparent conductive film, etc. used in liquid crystal displays, etc.) to prevent the surface of the component from being scratched during processing, assembly, inspection, transportation, etc., in the manufacturing process, or a carrier sheet.

[0018] The substrate contains a polyester-based resin. When the substrate contains a polyester-based resin, the effects of the present invention can be more effectively exhibited, and in particular, the problems that have conventionally occurred when a polyethylene-based film is used as the substrate can be resolved.

[0019] The pressure-sensitive adhesive layer is a urethane-based pressure-sensitive adhesive layer composed of a urethane-based pressure-sensitive adhesive. When the pressure-sensitive adhesive layer is a urethane-based pressure-sensitive adhesive layer composed of a urethane-based pressure-sensitive adhesive, the effects of the present invention can be more effectively exhibited. Furthermore, when the pressure-sensitive adhesive layer is a urethane-based pressure-sensitive adhesive layer composed of a urethane-based pressure-sensitive adhesive, for example, the problem of glue residue generation during processing can be suppressed.

[0020] In the pressure-sensitive adhesive layer-attached film, the thickness of the pressure-sensitive adhesive layer is typically 4.0 μm to 10.0 μm. By adjusting the thickness of the pressure-sensitive adhesive layer within the above range, the effects of the present invention can be more effectively achieved. If the thickness of the pressure-sensitive adhesive layer is too small and outside the above range, there is a risk of dents being formed due to foreign matter, for example, when a roll is produced from the pressure-sensitive adhesive layer-attached film. If the thickness of the pressure-sensitive adhesive layer is too large and outside the above range, there is a risk of air bubbles being trapped or wrinkles being formed, making it difficult to wind up the pressure-sensitive adhesive layer-attached film, for example, when a roll is produced from the pressure-sensitive adhesive layer-attached film.

[0021] The low-speed peel strength of the pressure-sensitive adhesive layer-attached film, measured at a temperature of 23°C and a humidity of 50% RH at a peel speed of 0.3 m / min and a peel angle of 180° from the release layer, is preferably less than 0.01 N / 25 mm, and may be 0.008 N / 25 mm or less, or may be 0.006 N / 25 mm or less. The lower limit of the low-speed peel strength is preferably 0.002 N / 25 mm or more, so as to prevent slippage during winding. If the low-speed peel strength is too high, for example, noise may be generated when unwinding the wound roll, adhesive residue may remain on the equipment, or a large amount of static electricity may be generated during peeling after lamination. Details of the method for measuring the low-speed peel strength will be described later.

[0022] The high-speed peel strength of the pressure-sensitive adhesive layer-attached film, measured at a temperature of 23°C and a humidity of 50% RH at a peel speed of 30 m / min and a peel angle of 180° from the release layer, is preferably less than 0.15 N / 25 mm, and may be 0.13 N / 25 mm or less, or may be 0.11 N / 25 mm or less. The lower limit of the high-speed peel strength is preferably 0.05 N / 25 mm or more, so as to prevent slippage during winding. If the high-speed peel strength is too high, for example, when the pressure-sensitive adhesive layer-attached film is unwound from a roll, peeling may be heavy, making unwinding difficult. Details of the method for measuring the high-speed peel strength will be described later.

[0023] The total thickness of the pressure-sensitive adhesive layer-attached film is preferably 20 μm to 100 μm, more preferably 25 μm to 80 μm, and even more preferably 30 μm to 60 μm. When the total thickness of the pressure-sensitive adhesive layer-attached film is within the above range, the effects of the present invention can be more effectively exhibited.

[0024] The pressure-sensitive adhesive layer-attached film can be produced by any suitable method as long as it does not impair the effects of the present invention. Such production methods include, for example, (1) a method of applying a solution or a hot-melt liquid of a material for forming a pressure-sensitive adhesive layer onto a substrate provided with a release layer, and drying it as necessary; (2) a method of applying a solution or a hot-melt liquid of a material for forming a pressure-sensitive adhesive layer onto a release liner, and drying it as necessary to form a pressure-sensitive adhesive layer, and then transferring the resultant pressure-sensitive adhesive layer onto a substrate provided with a release layer; (3) a method of extruding a material for forming a pressure-sensitive adhesive layer onto a substrate provided with a release layer to form a two-layer or multi-layer coating; (4) a method of extruding a substrate and a pressure-sensitive adhesive layer provided with a release layer onto a substrate in a two-layer or multi-layer configuration; (5) a method of laminating a pressure-sensitive adhesive layer provided with a release layer onto a substrate in a single layer, or a method of laminating a pressure-sensitive adhesive layer together with a laminate layer onto a substrate in a two-layer or multi-layer configuration; (6) a method of laminating a pressure-sensitive adhesive layer onto a substrate-forming material, such as a film provided with a release layer or a laminate layer, in a two-layer or multi-layer configuration. Any appropriate method can be used for the coating, such as a roll coater method, a comma coater method, a die coater method, a reverse coater method, a silk screen method, or a gravure coater method.

[0025] <1-1. Release Layer> Any appropriate material can be used as the material for the release layer as long as it does not impair the effects of the present invention. Examples of such materials include silicone-based release agents, fluorine-based release agents, long-chain alkyl-based release agents, and fatty acid amide-based release agents. The release layer can be formed as a coating layer.

[0026] The thickness of the release layer may be any appropriate thickness depending on the purpose, as long as it does not impair the effects of the present invention. Such a thickness is, for example, 1 nm to 3000 nm, may be 10 nm to 2000 nm, may be 10 nm to 1500 nm, may be 10 nm to 1000 nm, or may be 10 nm to 500 nm.

[0027] The release layer may be a single layer or two or more layers.

[0028] The release layer can be formed, for example, by applying the above-mentioned forming material to the substrate by a conventionally known coating method such as reverse gravure coating, bar coating, or die coating, and then curing the applied material by heat treatment, usually at about 120° C. to 200° C. If necessary, the heat treatment may be combined with irradiation with active energy rays such as ultraviolet light.

[0029] As the release layer, a base material on which a release layer has been previously provided may be used.

[0030] <1-2. Substrate> The substrate contains a polyester resin, which can bring about the effects of the present invention.

[0031] The content of the polyester resin in the substrate is preferably more than 50% by weight and not more than 100% by weight, more preferably 70% to 100% by weight, even more preferably 90% to 100% by weight, particularly preferably 95% to 100% by weight, and most preferably 98% to 100% by weight. When the content of the polyester resin in the substrate is within the above range, the effects of the present invention can be more effectively exhibited.

[0032] As the polyester-based resin, any appropriate polyester-based resin can be used as long as it does not impair the effects of the present invention. In terms of being able to further exhibit the effects of the present invention, such polyester-based resin is preferably at least one selected from the group consisting of polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polybutylene terephthalate (PBT), and more preferably polyethylene terephthalate (PET).

[0033] The elastic modulus of the substrate is, for example, 0.1 GPa to 10 GPa, and may be 2 GPa to 5 GPa. When the elastic modulus of the substrate is within the above range, the effects of the present invention can be more effectively exhibited.

[0034] The haze of the substrate is, for example, 15% or less, or may be 10% or less, 7% or less, or 5% or less. If the haze of the substrate is within the above range, foreign matter can be checked during production using a camera or automatic inspection device.

[0035] The thickness of the substrate is preferably 1 μm to 300 μm, more preferably 5 μm to 200 μm, even more preferably 10 μm to 150 μm, still more preferably 20 μm to 100 μm, particularly preferably 30 μm to 80 μm, and most preferably 30 μm to 60 μm, in terms of being able to further exhibit the effects of the present invention.

[0036] The substrate may be made up of only one layer, or two or more layers.

[0037] The substrate may be stretched.

[0038] The substrate may be subjected to a surface treatment, such as corona treatment, plasma treatment, chromic acid treatment, ozone exposure, flame exposure, high-voltage shock exposure, ionizing radiation treatment, or coating with a primer.

[0039] The substrate may contain any suitable additives as long as they do not impair the effects of the present invention. Examples of such additives include antistatic agents, colorants, powders such as pigments, surfactants, plasticizers, tackifiers, low-molecular-weight polymers, surface lubricants, leveling agents, antioxidants, corrosion inhibitors, light stabilizers, UV absorbers, polymerization inhibitors, silane coupling agents, inorganic fillers, organic fillers, metal powders, organic particles, and inorganic particles.

[0040] <1-3. Pressure-sensitive adhesive layer> The pressure-sensitive adhesive layer may be a single layer or two or more layers.

[0041] As mentioned above, the thickness of the pressure-sensitive adhesive layer is typically 4.0 μm to 10.0 μm. By adjusting the thickness of the pressure-sensitive adhesive layer within the above range, the effects of the present invention can be more effectively achieved. If the thickness of the pressure-sensitive adhesive layer is too small and outside the above range, there is a risk of dents due to foreign matter, for example, occurring when a roll is produced from the pressure-sensitive adhesive layer-attached film. If the thickness of the pressure-sensitive adhesive layer is too large and outside the above range, there is a risk of air bubbles being trapped or wrinkles occurring, for example, when a roll is produced from the pressure-sensitive adhesive layer-attached film, making it difficult to wind up the pressure-sensitive adhesive layer-attached film.

[0042] As described above, the pressure-sensitive adhesive layer is a urethane-based pressure-sensitive adhesive layer composed of a urethane-based pressure-sensitive adhesive. When the pressure-sensitive adhesive layer is a urethane-based pressure-sensitive adhesive layer composed of a urethane-based pressure-sensitive adhesive, the effects of the present invention can be more effectively exhibited. Furthermore, when the pressure-sensitive adhesive layer is a urethane-based pressure-sensitive adhesive layer composed of a urethane-based pressure-sensitive adhesive, for example, the problem of glue residue generation during processing can be suppressed.

[0043] The urethane-based pressure-sensitive adhesive is formed from a urethane-based pressure-sensitive adhesive composition. That is, the urethane-based pressure-sensitive adhesive formed from the urethane-based pressure-sensitive adhesive composition forms a layer, thereby forming a pressure-sensitive adhesive layer.

[0044] A urethane-based pressure-sensitive adhesive can be defined as something formed from a urethane-based pressure-sensitive adhesive composition. This is because a urethane-based pressure-sensitive adhesive becomes a urethane-based pressure-sensitive adhesive when a urethane-based pressure-sensitive adhesive composition undergoes a crosslinking reaction due to heating or ultraviolet irradiation, etc., and therefore it is impossible and impractical to directly identify a urethane-based pressure-sensitive adhesive by its structure ("impossible / impractical circumstances"). Therefore, the definition of "something formed from a urethane-based pressure-sensitive adhesive composition" appropriately identifies a urethane-based pressure-sensitive adhesive as a "product."

[0045] The urethane-based pressure-sensitive adhesive is formed from a urethane-based pressure-sensitive adhesive composition. Any appropriate method may be employed as this formation method, provided that the effects of the present invention are not impaired. Examples of such formation methods include conventionally known methods for forming urethane-based pressure-sensitive adhesives. Specific examples of such formation methods include a method in which a urethane-based pressure-sensitive adhesive composition is directly applied to any suitable substrate film (e.g., the substrate in a pressure-sensitive adhesive layer-attached film) and then dried or cured (direct method), and a method in which a urethane-based pressure-sensitive adhesive composition is applied to the surface (release surface) of a release liner and then dried or cured to form a urethane-based pressure-sensitive adhesive layer on the surface, and then the urethane-based pressure-sensitive adhesive layer is then laminated to any suitable substrate film (e.g., the substrate in a pressure-sensitive adhesive layer-attached film) to transfer the urethane-based pressure-sensitive adhesive layer (transfer method). From the viewpoint of the anchoring properties of the pressure-sensitive adhesive layer, the direct method is typically preferably employed. Regarding the various conditions used in these formation methods, the various conditions used in conventionally known methods for forming urethane-based pressure-sensitive adhesives may be employed.

[0046] As a method for providing (typically applying) such a urethane-based pressure-sensitive adhesive layer, various conventionally known methods can be appropriately adopted, such as roll coating, gravure coating, reverse coating, kiss coating, dip roll coating, bar coating, roll brushing, spray coating, knife coating, air knife coating, spray coating, comma coating, direct coating, and coating with a die coater.

[0047] The urethane pressure-sensitive adhesive composition can be dried under heating (for example, by heating to about 60° C. to 150° C.) as needed. As a means for curing the urethane pressure-sensitive adhesive composition, for example, ultraviolet rays, laser rays, α rays, β rays, γ rays, X-rays, or electron beams can be appropriately used.

[0048] There are two types of manufacturing methods for urethane-based pressure-sensitive adhesives: the one-shot method, in which a urethane-based pressure-sensitive adhesive is manufactured by directly reacting a polyol with a polyfunctional isocyanate compound without using a urethane prepolymer, and the prepolymer method, in which a urethane-based pressure-sensitive adhesive is manufactured by reacting a urethane prepolymer with a polyfunctional isocyanate compound. Here, because a "urethane prepolymer" may have multiple hydroxyl groups, in order to clearly distinguish it from a "polyol," the "polyol (A1)" in the description of the present invention does not include the "urethane prepolymer (A2)" in the description of the present invention.

[0049] <1-3-1. Urethane-based Pressure-Sensitive Adhesive Produced by One-Shot Method> One embodiment of the polyurethane-based pressure-sensitive adhesive is a polyurethane-based pressure-sensitive adhesive obtained by curing a urethane-based pressure-sensitive adhesive composition containing a polyol (A1) and a polyfunctional isocyanate compound (B). That is, the urethane-based pressure-sensitive adhesive composition in this embodiment contains a polyol (A1) and a polyfunctional isocyanate compound (B).

[0050] In this embodiment, the total content of the polyol (A1) and the polyfunctional isocyanate compound (B) in the urethane-based pressure-sensitive adhesive composition, excluding the solvent, is preferably 50% by weight to 100% by weight, more preferably 55% by weight to 95% by weight, even more preferably 60% by weight to 90% by weight, particularly preferably 65% ​​by weight to 85% by weight, and most preferably 70% by weight to 80% by weight.

[0051] [1-3-1-a. Polyol (A1)] The polyol (A1) may be one kind or two or more kinds.

[0052] Any suitable polyol having two or more OH groups may be used as the polyol (A1), such as a polyol (diol) having two OH groups, a polyol (triol) having three OH groups, a polyol (tetraol) having four OH groups, a polyol (pentaol) having five OH groups, or a polyol (hexaol) having six OH groups.

[0053] In the present invention, the polyol (A1) is preferably a polyol (triol) having three OH groups as an essential component. When the polyol (A1) is a polyol (triol) having three OH groups as an essential component, the effects of the present invention can be more effectively exhibited.

[0054] The content of the polyol having three OH groups (triol) in the polyol (A1) is preferably 50% by weight to 100% by weight, more preferably 70% by weight to 100% by weight, even more preferably 80% by weight to 100% by weight, still more preferably 90% by weight to 100% by weight, particularly preferably 95% by weight to 100% by weight, and most preferably substantially 100% by weight.

[0055] The polyol (A1) preferably contains a polyol having a number average molecular weight Mn of 400 to 20,000. The content of the polyol having a number average molecular weight Mn of 400 to 20,000 in the polyol (A1) is preferably 50% by weight to 100% by weight, more preferably 70% by weight to 100% by weight, even more preferably 90% by weight to 100% by weight, particularly preferably 95% by weight to 100% by weight, and most preferably substantially 100% by weight. By adjusting the content of the polyol having a number average molecular weight Mn of 400 to 20,000 in the polyol (A1) to fall within the above range, the effects of the present invention can be more effectively exhibited.

[0056] In the present invention, when a polyol (triol) having three OH groups is used as an essential component of the polyol (A1), preferably a triol having a number average molecular weight Mn of 7,000 to 20,000, a triol having a number average molecular weight Mn of 2,000 to 6,000, and a triol having a number average molecular weight Mn of 400 to 1,900 are used in combination, more preferably a triol having a number average molecular weight Mn of 8,000 to 15,000, a triol having a number average molecular weight Mn of 2,000 to 5,000, and a triol having a number average molecular weight Mn of 500 to 1,800 are used in combination, and even more preferably a triol having a number average molecular weight Mn of 8,000 to 12,000, a triol having a number average molecular weight Mn of 2,000 to 4,000, and a triol having a number average molecular weight Mn of 500 to 1,500 are used in combination. The use of such three types of triols in combination can further enhance the effects of the present invention.

[0057] Examples of the polyol (A1) include polyester polyols, polyether polyols, polycaprolactone polyols, polycarbonate polyols, and castor oil polyols.

[0058] The polyester polyol can be obtained, for example, by an esterification reaction between a polyol component and an acid component.

[0059] Examples of polyol components include ethylene glycol, diethylene 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, trimethylolpropane, pentaerythritol, hexanetriol, and polypropylene glycol.

[0060] Examples of the acid component include succinic acid, methylsuccinic acid, adipic acid, pimelic acid, azelaic acid, sebacic acid, 1,12-dodecanedioic acid, 1,14-tetradecanedioic acid, dimer acid, 2-methyl-1,4-cyclohexanedicarboxylic acid, 2-ethyl-1,4-cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, phthalic acid, isophthalic acid, terephthalic acid, 1,4-naphthalenedicarboxylic acid, 4,4'-biphenyldicarboxylic acid, and acid anhydrides thereof.

[0061] Examples of polyether polyols include polyether polyols obtained by addition polymerization of alkylene oxides such as ethylene oxide, propylene oxide, and butylene oxide using as initiators water, low-molecular-weight polyols (propylene glycol, ethylene glycol, glycerin, trimethylolpropane, pentaerythritol, etc.), bisphenols (bisphenol A, etc.), and dihydroxybenzenes (catechol, resorcinol, hydroquinone, etc.). Specific examples of polyether polyols include polyethylene glycol, polypropylene glycol, and polytetramethylene glycol.

[0062] Examples of polycaprolactone polyols include caprolactone-based polyester diols obtained by ring-opening polymerization of cyclic ester monomers such as ε-caprolactone and σ-valerolactone.

[0063] Examples of polycarbonate polyols include polycarbonate polyols obtained by polycondensation of the above polyol components with phosgene; polycarbonate polyols obtained by transesterification of the above polyol components with carbonate diesters such as dimethyl carbonate, diethyl carbonate, dipropyl carbonate, diisopropyl carbonate, dibutyl carbonate, ethylbutyl carbonate, ethylene carbonate, propylene carbonate, diphenyl carbonate, and dibenzyl carbonate; copolymer polycarbonate polyols obtained by combining two or more of the above polyol components; polycarbonate polyols obtained by esterification of the above various polycarbonate polyols with carboxyl group-containing compounds; and various Examples of the polycarbonate polyol include polycarbonate polyols obtained by etherifying polycarbonate polyols with hydroxyl group-containing compounds; polycarbonate polyols obtained by transesterifying the above-mentioned various polycarbonate polyols with ester compounds; polycarbonate polyols obtained by transesterifying the above-mentioned various polycarbonate polyols with hydroxyl group-containing compounds; polyester-based polycarbonate polyols obtained by polycondensation reaction of the above-mentioned various polycarbonate polyols with dicarboxylic acid compounds; and copolymerized polyether-based polycarbonate polyols obtained by copolymerizing the above-mentioned various polycarbonate polyols with alkylene oxides.

[0064] Examples of castor oil-based polyols include castor oil-based polyols obtained by reacting castor oil fatty acids with the above-mentioned polyol components.Specific examples of castor oil-based polyols include castor oil-based polyols obtained by reacting castor oil fatty acids with polypropylene glycol.

[0065] [1-3-1-b. Polyfunctional isocyanate compound (B) used in one-shot method] The polyfunctional isocyanate compound (B) used in the one-shot method may be one kind or two or more kinds.

[0066] As the polyfunctional isocyanate compound (B), any appropriate polyfunctional isocyanate compound that can be used in a urethanization reaction can be used, such as a polyfunctional aliphatic isocyanate compound, a polyfunctional alicyclic isocyanate compound, or a polyfunctional aromatic isocyanate compound.

[0067] 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, and 2,4,4-trimethylhexamethylene diisocyanate.

[0068] 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 tolylene diisocyanate, and hydrogenated tetramethylxylylene diisocyanate.

[0069] Examples of polyfunctional aromatic isocyanate compounds include phenylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene 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, and xylylene diisocyanate.

[0070] Examples of the polyfunctional isocyanate compound (B) include trimethylolpropane adducts of the various polyfunctional isocyanate compounds described above, biuret adducts obtained by reacting with water, and ternary isocyanurate ring-containing adducts. These may also be used in combination.

[0071] The content of the polyfunctional isocyanate compound (B) relative to the polyol (A1) is preferably 5 to 60% by weight, more preferably 8 to 60% by weight, and even more preferably 10 to 60% by weight. By adjusting the content of the polyfunctional isocyanate compound (B) within the above range, the effects of the present invention can be more effectively exhibited.

[0072] The equivalent ratio of NCO groups to OH groups in the polyol (A1) and the polyfunctional isocyanate compound (B) is, in terms of NCO groups / OH groups, more than 1.0 and not more than 5.0, preferably 1.1 to 5.0, more preferably 1.2 to 4.0, even more preferably 1.5 to 3.5, and particularly preferably 1.8 to 3.0, in terms of NCO groups / OH groups, from the viewpoint of further exhibiting the effects of the present invention.

[0073] [1-3-1-c. Other Components] The urethane-based pressure-sensitive adhesive composition may contain any appropriate other components in any appropriate amount within the scope of not impairing the effects of the present invention. Examples of such other components include other resin components, crosslinking agents other than the polyfunctional isocyanate compound (B), crosslinking retarders, ionic compounds, fluorine-based additives, silicone-based additives, fatty acid esters, tackifiers, inorganic fillers, organic fillers, metal powders, pigments, foil-like materials, softeners, antioxidants, conductive agents, UV absorbers, antioxidants, light stabilizers, surface lubricants, leveling agents, corrosion inhibitors, heat stabilizers, polymerization inhibitors, lubricants, solvents, and catalysts.

[0074] <1-3-2. Urethane-based PSA produced by prepolymer method> One embodiment of the polyurethane-based PSA is a polyurethane-based PSA obtained by curing a urethane-based PSA composition containing a urethane prepolymer (A2) and a polyfunctional isocyanate compound (B). That is, the urethane-based PSA composition in this embodiment contains the urethane prepolymer (A2) and the polyfunctional isocyanate compound (B).

[0075] The total content of the urethane prepolymer (A2) and the polyfunctional isocyanate compound (B) in the urethane-based pressure-sensitive adhesive composition in this embodiment, excluding the solvent, is preferably 50% by weight to 100% by weight, more preferably 55% by weight to 95% by weight, even more preferably 60% by weight to 90% by weight, particularly preferably 65% ​​by weight to 85% by weight, and most preferably 70% by weight to 80% by weight.

[0076] [1-3-2-a. Urethane Prepolymer (A2)] The urethane prepolymer (A2) may be of one type only, or of two or more types.

[0077] The number average molecular weight Mn of the urethane prepolymer (A2) is preferably 3,000 to 1,000,000.

[0078] The urethane prepolymer (A2) is preferably a polyurethane polyol, and more preferably is obtained by reacting a polyester polyol (a21) or a polyether polyol (a22), either alone or in the form of a mixture of (a21) and (a22), with an organic polyisocyanate compound (a23) in the presence or absence of a catalyst.

[0079] Any appropriate polyester polyol can be used as the polyester polyol (a21). Examples of such polyester polyols (a21) include polyester polyols obtained by reacting an acid component with a glycol component. Examples of acid components include terephthalic acid, adipic acid, azelaic acid, sebacic acid, phthalic anhydride, isophthalic acid, and trimellitic acid. Examples of glycol components include ethylene glycol, propylene glycol, diethylene glycol, butylene glycol, 1,6-hexane glycol, 3-methyl-1,5-pentanediol, 3,3'-dimethylolheptane, polyoxyethylene glycol, polyoxypropylene glycol, 1,4-butanediol, neopentyl glycol, and butylethylpentanediol. Examples of polyol components include glycerin, trimethylolpropane, and pentaerythritol. Other examples of the polyester polyol (a1) include polyester polyols obtained by ring-opening polymerization of lactones such as polycaprolactone, poly(β-methyl-γ-valerolactone), and polyvalerolactone.

[0080] The molecular weight of the polyester polyol (a21) can range from low to high. The molecular weight of the polyester polyol (a21) is preferably a number-average molecular weight Mn of 100 to 100,000. If the number-average molecular weight Mn is less than 100, the reactivity may be high and gelation may occur easily. If the number-average molecular weight Mn exceeds 100,000, the reactivity may be low and the cohesive force of the polyurethane polyol itself may be reduced. The amount of polyester polyol (a21) used is preferably 0 mol % to 90 mol % of the polyols constituting the polyurethane polyol.

[0081] Any suitable polyether polyol can be used as the polyether polyol (a22). Examples of such polyether polyols (a22) include polyether polyols obtained by polymerizing oxirane compounds such as ethylene oxide, propylene oxide, butylene oxide, and tetrahydrofuran using a low-molecular-weight polyol such as water, propylene glycol, ethylene glycol, glycerin, or trimethylolpropane as an initiator. Specific examples of such polyether polyols (a22) include polyether polyols having two or more functional groups, such as polypropylene glycol, polyethylene glycol, and polytetramethylene glycol.

[0082] The molecular weight of the polyether polyol (a22) can range from low to high. The molecular weight of the polyether polyol (a22) is preferably a number average molecular weight Mn of 100 to 100,000. If the number average molecular weight Mn is less than 100, the reactivity may be high and gelation may occur easily. If the number average molecular weight Mn exceeds 100,000, the reactivity may be low and the cohesive force of the polyurethane polyol itself may be reduced. The amount of polyether polyol (a22) used is preferably 0 mol % to 90 mol % of the polyols constituting the polyurethane polyol.

[0083] The polyether polyol (a22) can be used in combination, if necessary, by replacing a part thereof with glycols such as ethylene glycol, 1,4-butanediol, neopentyl glycol, butylethylpentanediol, glycerin, trimethylolpropane, and pentaerythritol, or polyvalent amines such as ethylenediamine, N-aminoethylethanolamine, isophoronediamine, and xylylenediamine.

[0084] As the polyether polyol (a22), only a bifunctional polyether polyol may be used, or a polyether polyol having a number average molecular weight Mn of 100 to 100,000 and at least three hydroxyl groups per molecule may be used in part or in whole. Using a polyether polyol having a number average molecular weight Mn of 100 to 100,000 and at least three hydroxyl groups per molecule in part or in whole as the polyether polyol (a22) can achieve a good balance between adhesive strength and removability. With such polyether polyols, if the number average molecular weight Mn is less than 100, the reactivity may be high and gelation may occur easily. Furthermore, if the number average molecular weight Mn of such polyether polyols exceeds 100,000, the reactivity may decrease and the cohesive strength of the polyurethane polyol itself may become weak. The number average molecular weight Mn of such polyether polyols is more preferably 100 to 10,000.

[0085] Any appropriate organic polyisocyanate compound can be used as the organic polyisocyanate compound (a23). Examples of such organic polyisocyanate compound (a23) include aromatic polyisocyanates, aliphatic polyisocyanates, araliphatic polyisocyanates, and alicyclic polyisocyanates.

[0086] Examples of aromatic polyisocyanates include 1,3-phenylene diisocyanate, 4,4'-diphenyl diisocyanate, 1,4-phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4'-toluidine diisocyanate, 2,4,6-triisocyanate toluene, 1,3,5-triisocyanate benzene, dianisidine diisocyanate, 4,4'-diphenyl ether diisocyanate, and 4,4',4"-triphenylmethane triisocyanate.

[0087] Examples of aliphatic polyisocyanates include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, dodecamethylene diisocyanate, and 2,4,4-trimethylhexamethylene diisocyanate.

[0088] Examples of the aromatic aliphatic polyisocyanate include ω,ω'-diisocyanate-1,3-dimethylbenzene, ω,ω'-diisocyanate-1,4-dimethylbenzene, ω,ω'-diisocyanate-1,4-diethylbenzene, 1,4-tetramethylxylylene diisocyanate, and 1,3-tetramethylxylylene diisocyanate.

[0089] Examples of alicyclic polyisocyanates include 3-isocyanatemethyl-3,5,5-trimethylcyclohexyl isocyanate, 1,3-cyclopentane diisocyanate, 1,3-cyclohexane diisocyanate, 1,4-cyclohexane diisocyanate, methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, 4,4'-methylenebis(cyclohexyl isocyanate), 1,4-bis(isocyanatemethyl)cyclohexane, and 1,4-bis(isocyanatemethyl)cyclohexane.

[0090] As the organic polyisocyanate compound (a23), a trimethylolpropane adduct, a biuret reacted with water, a trimer having an isocyanurate ring, etc. can be used in combination.

[0091] Any suitable catalyst can be used to obtain the polyurethane polyol, including, for example, a tertiary amine compound and an organometallic compound.

[0092] Examples of tertiary amine compounds include triethylamine, triethylenediamine, and 1,8-diazabicyclo(5,4,0)-undecene-7 (DBU).

[0093] Examples of organometallic compounds include tin-based compounds and non-tin-based compounds.

[0094] Examples of tin compounds include dibutyltin dichloride, dibutyltin oxide, dibutyltin dibromide, dibutyltin dimaleate, dibutyltin dilaurate (DBTDL), dibutyltin diacetate, dibutyltin sulfide, tributyltin sulfide, tributyltin oxide, tributyltin acetate, triethyltin ethoxide, tributyltin ethoxide, dioctyltin oxide, tributyltin chloride, tributyltin trichloroacetate, and tin 2-ethylhexanoate.

[0095] Examples of non-tin compounds include titanium compounds such as dibutyltitanium dichloride, tetrabutyltitanium, and butoxytitanium trichloride; lead compounds such as lead oleate, lead 2-ethylhexanoate, lead benzoate, and lead naphthenate; iron compounds such as iron 2-ethylhexanoate and iron acetylacetonate; cobalt compounds such as cobalt benzoate and cobalt 2-ethylhexanoate; zinc compounds such as zinc naphthenate and zinc 2-ethylhexanoate; and zirconium compounds such as zirconium naphthenate.

[0096] When a catalyst is used to obtain a polyurethane polyol, in a system containing two types of polyols, a polyester polyol (a21) and a polyether polyol (a22), problems such as gelation or cloudiness of the reaction solution are likely to occur in a system using a single catalyst due to the difference in reactivity between the two polyols. Therefore, by using two types of catalysts to obtain a polyurethane polyol, it becomes easier to control the reaction rate, catalyst selectivity, and the like, thereby solving these problems. Examples of such combinations of two types of catalysts include tertiary amine / organometallic, tin / non-tin, and tin / tin, with tin / tin being preferred, and a combination of dibutyltin dilaurate and tin 2-ethylhexanoate being more preferred. The blending ratio, by weight, of tin 2-ethylhexanoate / dibutyltin dilaurate is preferably less than 1, more preferably 0.2 to 0.6. If the blending ratio is 1 or more, gelation may occur due to the balance of catalytic activity.

[0097] When a catalyst is used in obtaining the polyurethane polyol, the amount of the catalyst used is preferably 0.01% by weight to 1.0% by weight based on the total amount of the polyester polyol (a21), the polyether polyol (a22), and the organic polyisocyanate compound (a23).

[0098] When a catalyst is used to obtain a polyurethane polyol, the reaction temperature is preferably less than 100° C., and more preferably 85° C. to 95° C. If the temperature is 100° C. or higher, it may become difficult to control the reaction rate and crosslinked structure, and it may become difficult to obtain a polyurethane polyol having a predetermined molecular weight.

[0099] When obtaining polyurethane polyol, it is not necessary to use a catalyst. In that case, the reaction temperature is preferably 100° C. or higher, more preferably 110° C. or higher. When obtaining polyurethane polyol without a catalyst, the reaction is preferably carried out for 3 hours or longer.

[0100] Examples of methods for obtaining polyurethane polyol include 1) a method in which a polyester polyol, a polyether polyol, a catalyst, and an organic polyisocyanate are charged into a volumetric flask, and 2) a method in which a polyester polyol, a polyether polyol, and a catalyst are charged into a flask and an organic polyisocyanate is added dropwise. As a method for obtaining polyurethane polyol, method 2) is preferred in terms of controlling the reaction.

[0101] Any suitable solvent may be used to obtain the polyurethane polyol. Examples of such solvents include methyl ethyl ketone, ethyl acetate, toluene, xylene, and acetone. Among these solvents, toluene is preferred.

[0102] [1-3-2-b. Polyfunctional Isocyanate Compound (B) Used in Prepolymer Method] The polyfunctional isocyanate compound (B) used in the prepolymer method may be one type or two or more types.

[0103] As the polyfunctional isocyanate compound (B) used in the prepolymer method, the above-mentioned polyfunctional isocyanate compound (B) used in the one-shot method can be used.

[0104] The equivalent ratio of NCO groups to OH groups in the urethane prepolymer (A2) and the polyfunctional isocyanate compound (B), expressed as NCO groups / OH groups, is preferably 5.0 or less, more preferably 0.01 to 4.75, even more preferably 0.02 to 4.5, particularly preferably 0.03 to 4.25, and most preferably 0.05 to 4.0. When the equivalent ratio of NCO groups / OH groups is within the above range, the effects of the present invention can be more effectively exhibited.

[0105] The content of the polyfunctional isocyanate compound (B) relative to the urethane prepolymer (A2) is preferably 0.01% by weight to 30% by weight, more preferably 0.05% by weight to 25% by weight, even more preferably 0.1% by weight to 20% by weight, particularly preferably 0.5% by weight to 17.5% by weight, and most preferably 1% by weight to 15% by weight. When the content of the polyfunctional isocyanate compound (B) is within the above range, the effects of the present invention can be more effectively exhibited.

[0106] As a method for forming a urethane-based pressure-sensitive adhesive from a urethane-based pressure-sensitive adhesive composition containing a urethane prepolymer (A2) and a polyfunctional isocyanate compound (B), any appropriate production method can be adopted as long as it is a method for producing a polyurethane-based resin using a so-called "urethane prepolymer" as a raw material.

[0107] <<2. Method for Producing a Roll of a Pressure-Sensitive Adhesive Layer-Attached Film>> A method for producing a roll of a pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention is a method for producing a roll from a long length of pressure-sensitive adhesive layer-attached film.

[0108] In a method for producing a roll of a pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention, a long length of the pressure-sensitive adhesive layer-attached film is wound around a winding shaft to form a roll. In a method for producing a roll of a pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention, the long length of the pressure-sensitive adhesive layer-attached film is wound around the winding shaft via a touch roll arranged in front of the winding shaft.

[0109] The length in the longitudinal direction of the long pressure-sensitive adhesive layer-attached film to be used in the method for producing a roll of pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention is, for example, 1000 m or more, and may be 2000 m to 10000 m, or may be 3000 m to 10000 m.

[0110] The length in the width direction of the long pressure-sensitive adhesive layer-attached film used in the method for producing a roll of pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention can be any appropriate length as long as the effects of the present invention are not impaired. Such a length in the width direction is, for example, 100 mm to 5000 mm, or may be 500 mm to 3000 mm, or may be 1000 mm to 2000 mm.

[0111] Fig. 1 is a schematic explanatory diagram of one embodiment of a winding device that can be used in a manufacturing method of a roll of a pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention. In Fig. 1, a long pressure-sensitive adhesive layer-attached film 101 passes through transport rolls 11 and 12 and a touch roll 200, and is wound around a winding shaft 300 to become a roll of a pressure-sensitive adhesive layer-attached film 102. The touch roll 200 is rotatably supported by a position adjustment unit 400.

[0112] As shown in Fig. 1, the touch roll 200 is arranged in front of the winding shaft 300 in a state in contact with the pressure-sensitive adhesive layer-attached film 101. The touch roll 200 is formed when the pressure-sensitive adhesive layer-attached film 101 is wound around the winding shaft 300 to form a roll 102 of pressure-sensitive adhesive layer-attached film, and is rotatably supported by a position adjustment unit 400 so as to apply a constant pressure to the pressure-sensitive adhesive layer-attached film 101 even if the diameter of the roll increases. The position adjustment unit 400 is, for example, a cylinder (such as an air cylinder). The position adjustment unit 400 can finely adjust the position of the touch roll 200.

[0113] As the touch roll, any appropriate type of touch roll may be used as long as it is applicable to film winding and does not impair the effects of the present invention. Examples of such touch rolls include crown rolls. Examples of materials for the touch roll include rubber.

[0114] Any suitable type of winding shaft can be used as the winding shaft, as long as it can be used to wind a film and does not impair the effects of the present invention. Examples of materials for such winding shafts include rubber, plastic, metal (e.g., aluminum), and composites thereof. The surface of the winding shaft may be coated with any suitable other material. The outer diameter of the winding shaft (the distance from the center of the winding core to the outer surface of the winding core) is, for example, 1 inch to 30 inches, and may be 2 inches to 15 inches. The shape of the winding shaft may be cylindrical or columnar.

[0115] In the method for producing a roll of a pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention, taper control may or may not be performed. However, in the method for producing a roll of a pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention, it is preferable not to perform taper control, as this can keep the tension of the pressure-sensitive adhesive layer-attached film constant and suppress air entrainment during winding.

[0116] In the method for producing a roll of a pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention, the end of the pressure-sensitive adhesive layer-attached film may or may not be knurled. However, in the method for producing a roll of a pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention, it is preferable that the end of the pressure-sensitive adhesive layer-attached film is not knurled, because this enables long winding while suppressing the entrapment of air bubbles, the occurrence of wrinkles, and dents.

[0117] In the method for producing a roll of a pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention, by appropriately adjusting the touch pressure P of the touch roll, it is possible to achieve long winding while suppressing the entrapment of air bubbles, the occurrence of wrinkles, and dents. The touch pressure P of the touch roll, as a linear pressure, is preferably 3.6 N / cm < P < 14.0 N / cm, and may be 3.9 N / cm < P < 13.0 N / cm, 4.2 N / cm < P < 11.0 N / cm, 4.3 N / cm < P < 10.0 N / cm, or 4.5 N / cm < P < 9.0 N / cm. By adjusting the touch pressure P of the touch roll within the above range, it is possible to achieve long winding while suppressing the entrapment of air bubbles, the occurrence of wrinkles, and dents. The touch pressure P was calculated as a linear pressure by dividing the pressure applied to the roll by the width of the film.

[0118] In the method for producing a roll of a pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention, by appropriately adjusting the product of the substrate thickness D and the touch pressure P, it becomes possible to wind up a long length while further suppressing the entrapment of air bubbles, the occurrence of wrinkles, and dents. The product D×P of the substrate thickness D and the touch pressure P is preferably 0.016 N < (D×P) < 0.075 N, and may be 0.017 < (D×P) < 0.063 N, 0.018 N < (D×P) < 0.050 N, or 0.020 N < (D×P) < 0.045 N. By adjusting the product D×P of the substrate thickness D and the touch pressure P within the above range, it becomes possible to wind up a long length while further suppressing the entrapment of air bubbles, the occurrence of wrinkles, and dents.

[0119] In the method for producing a roll of a pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention, by appropriately adjusting the surface hardness S of the touch roll, it becomes possible to wind up a long length of film while further suppressing the entrapment of air bubbles, the occurrence of wrinkles, and dents. The surface hardness S of the touch roll is preferably 30°<S<80°, and may be 40°<S<60°. By adjusting the surface hardness S of the touch roll within the above range, it becomes possible to wind up a long length of film while further suppressing the entrapment of air bubbles, the occurrence of wrinkles, and dents. The surface hardness S was measured using a durometer type A (manufactured by ASKER).

[0120] In the method for producing a roll of a pressure-sensitive adhesive layer-bonded film according to an embodiment of the present invention, by appropriately adjusting the winding tension T of the pressure-sensitive adhesive layer-bonded film on the winding shaft, it becomes possible to wind the film in a long length while further suppressing the entrapment of air bubbles, the occurrence of wrinkles, and the formation of dents. The winding tension T of the pressure-sensitive adhesive layer-bonded film on the winding shaft is preferably 200 N / m < T < 400 N / m, and may be 220 N / m < T < 380 N / m. By adjusting the winding tension T of the pressure-sensitive adhesive layer-bonded film on the winding shaft within the above range, it becomes possible to wind the film in a long length while further suppressing the entrapment of air bubbles, the occurrence of wrinkles, and the formation of dents.

[0121] In the method for producing a roll of a pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention, the line speed (winding speed) can be adjusted to any appropriate line speed as long as the effects of the present invention are not impaired. In terms of further exhibiting the effects of the present invention, the line speed is, for example, 1 m / min to 100 m / min, or may be 5 m / min to 80 m / min, 10 m / min to 60 m / min, 13 m / min to 40 m / min, 15 m / min to 30 m / min, or 15 m / min to 28 m / min.

[0122] In the method for producing a roll of a pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention, long winding is possible while suppressing the entrapment of air bubbles, the occurrence of wrinkles, and dents. Therefore, the roll length of the roll obtained in the method for producing a roll of a pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention is preferably 1,000 m or more, and may be 2,000 m to 10,000 m, or may be 3,000 m to 10,000 m.

[0123] According to the method for manufacturing a roll of a pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention, it is possible to perform long winding while suppressing the entrapment of air bubbles, the occurrence of wrinkles, and the formation of dents. For example, even if foreign matter with a maximum particle diameter of 3 μm or less is caught in the roll during production, it is possible to perform long winding without causing dents.

[0124] In a method for manufacturing a roll of a pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention, a urethane-based pressure-sensitive adhesive layer composed of a urethane-based pressure-sensitive adhesive is used as the pressure-sensitive adhesive layer of the pressure-sensitive adhesive layer-attached film. Furthermore, in the pressure-sensitive adhesive layer-attached film unwound from the roll, the pressure-sensitive adhesive layer is the outermost layer of the pressure-sensitive adhesive layer-attached film. Therefore, when the pressure-sensitive adhesive layer-attached film is unwound from the roll for bonding to another member, the surface of the pressure-sensitive adhesive layer can come into contact with the rotating roll, which makes it possible to clean the rotating roll without leaving any adhesive residue.

[0125] <<3. Roll of pressure-sensitive adhesive layer-attached film>> The roll of pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention is a roll of a long pressure-sensitive adhesive layer-attached film.

[0126] The roll length of the pressure-sensitive adhesive layer-attached film according to the embodiment of the present invention is preferably 1000 m or more, more preferably 2000 m or more, and even more preferably 3000 m or more. Conventional rolls of pressure-sensitive adhesive layer-attached film without a release liner have had difficulty in achieving long roll lengths due to the inclusion of air bubbles, the occurrence of wrinkles, and the occurrence of dents. According to the present invention, a roll having the above-mentioned long roll length can be provided.

[0127] As a description of the long pressure-sensitive adhesive layer-attached film that becomes the roll of the pressure-sensitive adhesive layer-attached film according to the embodiment of the present invention, the description of the pressure-sensitive adhesive layer-attached film in the previous section <<1. Pressure-sensitive adhesive layer-attached film>> can be directly cited.

[0128] The long pressure-sensitive adhesive layer-attached film to be wound into a roll of pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention preferably has a release layer, a substrate, and a pressure-sensitive adhesive layer in this order, the release layer and the pressure-sensitive adhesive layer being the outermost layers of the pressure-sensitive adhesive layer-attached film, the substrate containing a polyester resin, the pressure-sensitive adhesive layer being a urethane-based pressure-sensitive adhesive layer composed of a urethane-based pressure-sensitive adhesive, the pressure-sensitive adhesive layer having a thickness of 4.0 μm to 10.0 μm, and exhibiting a low-speed peel strength of the pressure-sensitive adhesive layer from the release layer measured at a temperature of 23° C. and a humidity of 50% RH at a peel speed of 0.3 m / min and a peel angle of 180° of less than 0.01 N / 25 mm. More preferably, the long pressure-sensitive adhesive layer to be wound into a roll of pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention is the pressure-sensitive adhesive layer-attached film described above in the section <<1. Pressure-sensitive adhesive layer-attached film>>.

[0129] The roll of the pressure-sensitive adhesive layer-attached film according to the embodiment of the present invention can suppress the entrapment of air bubbles and the occurrence of wrinkles, and can also suppress dents, even if the rolled length is long.

[0130] The roll of the pressure-sensitive adhesive layer-attached film according to the embodiment of the present invention can be produced by any appropriate method as long as the effects of the present invention are not impaired. Such a production method includes, for example, the method for producing the roll of the pressure-sensitive adhesive layer-attached film according to the embodiment of the present invention.

[0131] The present invention will be specifically described below using examples, but the present invention is not limited to these examples. The test and evaluation methods used in the examples are as follows. The term "parts" means "parts by weight" unless otherwise specified, and the term "%" means "% by weight" unless otherwise specified.

[0132] <Measurement of Thickness> The thickness of the pressure-sensitive adhesive layer in the Examples and Comparative Examples was measured using an interference film thickness meter (manufactured by Otsuka Electronics Co., Ltd., product name "MCPD-3700").

[0133] <Measurement of low-speed peel force measured at a peel speed of 0.3 m / min and a peel angle of 180 degrees> For two of the produced pressure-sensitive adhesive layer-attached films, the pressure-sensitive adhesive layer was pressed onto the release layer with a hand roller, and then the two were laminated together under pressure conditions of 0.25 MPa and 0.3 m / min, and left for 20 minutes in an environment of 23°C and 50% RH. Thereafter, the film was cut to a width of 25 mm and the side of the pressure-sensitive adhesive layer opposite the release layer was attached to a SUS plate (SUS304BA) and fixed thereto. Using a universal tensile tester (manufactured by Minebea Co., Ltd., product name: TCM-1kNB), the pressure-sensitive adhesive layer was peeled from the release layer at a peel speed of 0.3 m / min and a peel angle of 180 degrees, and the peel force measured was taken as the low-speed peel force.

[0134] <Measurement of high-speed peel strength measured at a peel speed of 30 m / min and a peel angle of 180 degrees> For the produced pressure-sensitive adhesive layer-attached film, the pressure-sensitive adhesive layer was pressed onto the release layer with a hand roller, and then laminated under pressure conditions of 0.25 MPa and 0.3 m / min, and left for 20 minutes in an environment of 23 ° C and 50% RH. Thereafter, the film was cut to a width of 25 mm, and the side of the pressure-sensitive adhesive layer opposite the release layer was attached and fixed to a SUS plate (SUS304BA). Using a universal tensile tester (manufactured by Minebea Co., Ltd., product name: TCM-1kNB), the pressure-sensitive adhesive layer was peeled from the release layer at a peel speed of 30 m / min and a peel angle of 180 degrees, and the peel strength measured was taken as the high-speed peel strength.

[0135] <Evaluation of Appearance of Bubbles and Wrinkles> After 3000 m of the pressure-sensitive adhesive layer-attached film was wound up, one turn was unwound from the roll and discarded, and then the roll surface was checked for bubbles and wrinkles. The evaluation was performed according to the following criteria. ◯: No bubbles or wrinkles within the area. △: No bubbles or wrinkles of 15 mm or more within the area. ×: Bubbles or wrinkles of 1 mm or more within the area.

[0136] <Evaluation of Appearance of Foreign Matter Dents> After 3000 m of the pressure-sensitive adhesive layer-attached film was wound up, one turn was unwound from the roll and discarded, and then the appearance of a 2 m length was checked. The evaluation was performed according to the following criteria. ◯: No foreign matter dents occurred. ×: Foreign matter dents occurred.

[0137] <Evaluation of Winding Length> The windings that were evaluated as being good (evaluated as "good") in both the appearance evaluation of bubbles and wrinkles and the appearance evaluation of foreign matter dents were further wound up to 4000 m, and the appearance evaluation of bubbles and wrinkles was carried out in the same manner as above.

[0138] [Synthesis Example 1] Preparation of urethane-based pressure-sensitive adhesive composition (1) 90 parts by weight of Preminol S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10,000), a polyol having three hydroxyl groups, as the polyol, 5 parts by weight of Sannix GP3000 (manufactured by Sanyo Chemical Industries, Ltd., Mn = 3,000), a polyol having three hydroxyl groups, 1 part by weight of Sannix GP1000 (manufactured by Sanyo Chemical Industries, Ltd., Mn = 1,000), a polyol having three hydroxyl groups, and an isocyanate compound (Coronate HX:C / HX, manufactured by Nippon Polyurethane Industry Co., Ltd.) as the crosslinking agent. 10 parts by weight of acrylic acid, 0.15 parts by weight of Narcem ferric iron (manufactured by Nippon Chemical Industry Co., Ltd.) as a catalyst, 0.04 parts by weight of polyether-modified silicone (manufactured by Shin-Etsu Chemical Co., Ltd., product name "KF6004") as a silicone compound, 0.8 parts by weight of Elexcel AS110 (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) as an ionic compound, and 5.0 parts by weight of Salacos 816 (L) (2-cetyl ethylhexanoate, molecular weight = 368, manufactured by The Nisshin Oillio Group, Ltd.) as a fatty acid ester were diluted with ethyl acetate to a total solids content of 20% by weight, to obtain a urethane-based pressure-sensitive adhesive composition (1).

[0139] Synthesis Example 2 Preparation of Acrylic Pressure-Sensitive Adhesive Composition (1) An acrylic pressure-sensitive adhesive (SK Dyne, manufactured by Soken Chemical & Engineering Co., Ltd.) was diluted with toluene to 35% by weight, and 5 parts by solid weight of a crosslinking agent (polyisocyanate, manufactured by Tosoh Corporation, Coronate HX), 0.5 parts by solid weight of a crosslinking catalyst (dioctyltin dilaurate, a tin catalyst, EMBIRIZER OL-1, manufactured by Tokyo Fine Chemical Co., Ltd.), and 10 parts by weight of acetylacetone were added per 100 parts by solid weight, and the mixture was mixed and stirred to prepare an acrylic pressure-sensitive adhesive composition (1).

[0140] [Production Example 1] Production of adhesive layer-attached film (1) A long PET film with a release layer (manufactured by Mitsubishi Chemical, trade name "MRF38", thickness = 38 μm, width direction length = 1480 mm, release layer thickness = 20 nm) was used as a substrate, and the urethane-based adhesive composition (1) obtained in Synthesis Example 1 was applied on a line to the surface of the substrate opposite the release layer at a line speed of 20 m / min so as to have a thickness after drying of 5 μm. This was then dried at 130°C for 30 seconds to form a urethane-based adhesive layer with a thickness of 5 μm, and a long adhesive layer-attached film (1) having a configuration of "release layer / substrate / adhesive layer" was produced on the line.

[0141] [Production Example 2] Production of adhesive layer-attached film (2)

[0113] The same procedure as in Production Example 1 was carried out except that a long PET film with a release layer (manufactured by Mitsubishi Chemical Corporation, product name "MRF50", thickness = 50 μm, width direction length = 1480 mm, release layer thickness = 20 nm) was used as the substrate, and a long adhesive layer-attached film (2) having a "release layer / substrate / adhesive layer" configuration was produced.

[0142] [Production Example 3] Production of pressure-sensitive adhesive layer-attached film (3) A long pressure-sensitive adhesive layer-attached film (3) having a configuration of "release layer / substrate / pressure-sensitive adhesive layer" was produced in the same manner as in Production Example 1, except that the urethane-based pressure-sensitive adhesive composition (1) was applied so that the thickness after drying was 7 μm.

[0143] [Production Example 4] Production of pressure-sensitive adhesive layer-attached film (4) A long pressure-sensitive adhesive layer-attached film (4) having a structure of "release layer / substrate / pressure-sensitive adhesive layer" was produced in the same manner as in Production Example 1, except that the urethane-based pressure-sensitive adhesive composition (1) was applied so that the thickness after drying was 10 μm.

[0144] [Production Example 5] Production of pressure-sensitive adhesive layer-attached film (5) A long pressure-sensitive adhesive layer-attached film (5) having a configuration of "release layer / substrate / pressure-sensitive adhesive layer" was produced in the same manner as in Production Example 1, except that the urethane-based pressure-sensitive adhesive composition (1) was applied so that the thickness after drying was 3 μm.

[0145] [Production Example 6] Production of a pressure-sensitive adhesive layer-attached film (6) A long PET film with a release layer (manufactured by Mitsubishi Chemical, trade name "MRF38", thickness = 38 μm, width direction length = 1480 mm, release layer thickness = 20 nm) was used as a substrate, and the acrylic pressure-sensitive adhesive composition (1) obtained in Synthesis Example 2 was applied on a line to the surface of the substrate opposite the release layer at a line speed of 20 m / min so as to give a thickness after drying of 5 μm. This was then dried at 130°C for 30 seconds to form an acrylic pressure-sensitive adhesive layer with a thickness of 5 μm, and a long pressure-sensitive adhesive layer-attached film (6) having a configuration of "release layer / substrate / pressure-sensitive adhesive layer" was produced on the line.

[0146] [Production Example 7] Production of adhesive layer-attached film (7) A long PET film (manufactured by Mitsubishi Chemical, trade name "Diafoil T100C38", thickness = 38 μm, width direction length = 1400 mm) was used as the substrate, and an anti-fouling layer made of a polyvinyl butyral compound was formed on one side of this substrate on a production line. Subsequently, on the production line, the urethane-based adhesive composition (1) obtained in Synthesis Example 1 was applied to the surface of the substrate opposite the anti-fouling layer at a line speed of 20 m / min so as to have a thickness after drying of 5 μm, and dried at 130° C. for 30 seconds to form a urethane-based adhesive layer with a thickness of 5 μm, and a long adhesive layer-attached film (7) having a configuration of "anti-fouling layer / substrate / adhesive layer" was produced on the production line.

[0147] [Production Example 8] Production of pressure-sensitive adhesive layer-attached film (8) A long pressure-sensitive adhesive layer-attached film (8) having a configuration of "release layer / substrate / pressure-sensitive adhesive layer" was produced in the same manner as in Production Example 1, except that the urethane-based pressure-sensitive adhesive composition (1) was applied so that the thickness after drying would be 12 μm.

[0148] [Examples 1 to 12, Comparative Examples 1 to 8] Using the winding device shown in Figure 1, any of the pressure-sensitive adhesive layer-attached films (1) to (8) obtained in Production Examples 1 to 8 was wound around a winding shaft under the conditions shown in Table 1, to obtain wound bodies (1) to (7), (C1) to (C8). The results are shown in Table 1.

[0149]

[0150] The method for producing a roll of a pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention can be effectively used for producing rolls of various films used in the manufacturing processes of optical members and electronic members, for example. Also, the roll of a pressure-sensitive adhesive layer-attached film according to an embodiment of the present invention can be effectively used as a roll of various films used in the manufacturing processes of optical members and electronic members, for example.

Claims

1. A method for producing a roll of a long adhesive-layered film, wherein the adhesive-layered film has a release layer, a base material, and an adhesive layer in that order, the release layer and the adhesive layer are the outermost layers of the adhesive-layered film, the base material contains a polyester-based resin, the adhesive layer is a urethane-based adhesive layer made of a urethane-based adhesive, and the adhesive layer has a thickness of 4.0 μm to 10.0 μm, the adhesive-layered film is wound around a winding shaft via a touch roll positioned in front of the winding shaft to form a roll, and the touch pressure P of the touch roll is in the range of 3.6 N / cm<P<14.0 N / cm in terms of linear pressure.

2. The method for producing a roll of a pressure-sensitive adhesive layer-attached film according to claim 1, wherein the touch pressure P of the touch roll is, in terms of linear pressure, 4.3 N / cm<P<10.0 N / cm.

3. The method for producing a roll of a pressure-sensitive adhesive layer-attached film according to claim 1, wherein the product of the thickness D of the substrate and the touch pressure P is 0.018 N < (D x P) < 0.050 N.

4. The method for producing a roll of a film with a pressure-sensitive adhesive layer according to claim 1, wherein the surface hardness S of the touch roll is 30°<S<80°.

5. The method for producing a roll of a pressure-sensitive adhesive layer-attached film according to claim 1, wherein the winding tension T of the pressure-sensitive adhesive layer-attached film on the winding shaft is 200 N / m < T < 400 N / m.

6. The method for producing a roll of a film with a pressure-sensitive adhesive layer according to claim 1, wherein the low-speed peel strength of the pressure-sensitive adhesive layer from the release layer measured at a peel speed of 0.3 m / min and a peel angle of 180 degrees at a temperature of 23°C and a humidity of 50% RH is less than 0.01 N / 25 mm.

7. The method for producing a roll of a film with a pressure-sensitive adhesive layer according to claim 1, wherein the high-speed peel strength of the pressure-sensitive adhesive layer from the release layer measured at a peel speed of 30 m / min and a peel angle of 180 degrees at a temperature of 23°C and a humidity of 50% RH is less than 0.15 N / 25 mm.

8. The method for producing a roll of a pressure-sensitive adhesive layer-attached film according to claim 1, wherein the roll has a winding length of 3,000 m or more.

9. A roll of a long adhesive-layered film, the adhesive-layered film having a release layer, a substrate, and an adhesive layer in this order, the release layer and the adhesive layer being the outermost layers of the adhesive-layered film, the substrate comprising a polyester-based resin, the adhesive layer being a urethane-based adhesive layer composed of a urethane-based adhesive, the adhesive layer having a thickness of 4.0 μm to 10.0 μm, and the low-speed peel strength of the adhesive layer from the release layer measured at a peel speed of 0.3 m / min and a peel angle of 180 degrees at a temperature of 23°C and a humidity of 50% RH is less than 0.01 N / 25 mm.

10. A roll of a film with a pressure-sensitive adhesive layer according to claim 9, wherein the high-speed peel strength of the pressure-sensitive adhesive layer from the release layer measured at a peel speed of 30 m / min and a peel angle of 180 degrees at a temperature of 23°C and a humidity of 50% RH is less than 0.15 N / 25 mm.

11. A roll of the pressure-sensitive adhesive layer-attached film according to claim 9, having a roll length of 3,000 m or more.

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