Adhesive sheet for wind turbine blade and wound body thereof as well as maintenance method of blade for wind turbine blade

Abstract

To provide an adhesive sheet for a wind turbine blade capable of protecting a wind turbine blade for a long time due to high adhesiveness to a wind turbine blade, capable of readily peeling due to a small amount of adhesive deposit even when deteriorated, not likely to occur a winkle during bonding and capable of simply performing a series of operations during repair operation.SOLUTION: The adhesive sheet for wind turbine blades of the present invention is an adhesive sheet for bonding to wind turbine blades, comprising a laminate that includes a substrate layer and an adhesive layer, where the maximum thickness of the substrate layer is more than 500 μm and less than or equal to 3000 μm, the thickness of the adhesive layer is more than or equal to 100 μm, and the mass per unit area of the laminate is less than 1000 g / m2.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an adhesive sheet for wind power generator blades, a roll of the adhesive sheet, and a method for repairing wind power generator blades. [Background technology]

[0002] Conventionally, adhesive sheets have been widely used for various purposes, such as surface protection, repair, and bonding, and are highly useful materials. For example, adhesive sheets are suitably used as decorative sheets, anti-chipping films for automobiles, and protective films for protecting aircraft wings (see, for example, Patent Document 1). Generally, adhesive sheets have a laminated structure in which an adhesive layer is laminated on a base layer, and are applied by laminating the surface on the adhesive layer side to the target area. For example, when performing repair work using a repair adhesive sheet, the surface on the adhesive layer side of the adhesive sheet is laminated to the area to be repaired.

[0003] For example, Patent Document 1 discloses a technology that allows for easy repair of scratches by adhering a laminated protective sheet having an adhesive layer, an intermediate fabric layer, and a durable surface layer to at least a portion of the leading edge of an FRP wing body body. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2012 / 102294 Summary of the Invention [Problem to be solved by the invention]

[0005] Adhesive sheets are applied to wind turbine blades to protect them from surface deterioration (erosion), scratches, etc. In recent years, there has been a demand for adhesive sheets that can protect wind turbine blades for longer periods of time, but conventional adhesive sheets have low adhesive holding power for wind turbine blades, resulting in frequent repairs.

[0006] Furthermore, when repairs are performed using an adhesive sheet, the old adhesive sheet (i.e., the deteriorated adhesive sheet) already attached to the object to be repaired is first peeled off, and the repair area is cleaned and primed as necessary, and then a new adhesive sheet is applied to complete the repair. For this reason, adhesive sheets are required to be easily peeled off even after deterioration, for example, to leave little adhesive residue (glue residue). Furthermore, they are also required to be wrinkle-resistant and easy to apply during installation (attachment). In particular, when repairing wind turbine blades, such work requires high-altitude work on unstable scaffolding, so ease of application is highly desirable.

[0007] The present invention has been made in view of the above, and aims to provide an adhesive sheet for wind power generator blades that has high adhesion to wind power generator blades, can protect wind power generator blades for long periods of time, leaves little adhesive residue even if the blades deteriorate, allows easy peeling, and is less likely to wrinkle when applied, simplifying the series of repair work. Another aim of the present invention is to provide a roll of the adhesive sheet for wind power generator blades and a method for repairing wind power generator blades. [Means for solving the problem]

[0008] As a result of extensive research to achieve the above-mentioned object, the inventors discovered that the above-mentioned object can be achieved by using a laminate having a mass per unit area within a predetermined range and having thicknesses of the base layer and adhesive layer within a predetermined range, and thus completed the present invention.

[0009] That is, the present invention includes, for example, the subject matter described in the following sections. Item 1 An adhesive sheet for attaching to a wind power generation blade, A laminate in which a base layer and an adhesive layer are laminated, The maximum thickness of the base layer is 500 μm or more and 3000 μm or less, The adhesive layer has a thickness of 100 μm or more, The mass per unit area of ​​the laminate is 1000 g / m 2 is less than Adhesive sheet for wind turbine blades. Section 2 Item 2. The adhesive sheet for wind power generation blades according to Item 1, wherein the base layer contains at least one resin selected from the group consisting of urethane resin, urea resin, polyethylene terephthalate resin, vinyl chloride resin, vinyl acetate resin, acrylic resin, and polybutylene terephthalate resin. Term 2´ Item 3. An adhesive sheet for wind power generation blades according to Item 2, wherein the substrate layer is a thermoplastic urethane resin (TPU). Section 3 Item 3. An adhesive sheet for wind power generation blades according to Item 1 or 2, wherein the adhesive layer has a glass transition temperature of −25° C. or higher and 20° C. or lower. Section 4 Item 4. An adhesive sheet for wind power generator blades according to any one of Items 1 to 3, wherein the stiffness of the laminate is 10 mN / mm or more and 85 mN / mm or less. Section 5 Item 5. A wound body in which the adhesive sheet for wind power generation blades according to any one of items 1 to 4 is wound around a cylindrical core material. Section 6 Item 5. A method for repairing a wind power generation blade using the adhesive sheet for wind power generation blades according to any one of Items 1 to 4, comprising a step R of attaching the adhesive sheet for wind power generation blades to a location of the wind power generation blade to be repaired. Section 7 Item 7. The method for repairing a wind power generation blade according to Item 6, further comprising, before step R, step A of peeling off the deteriorated adhesive sheet for a wind power generation blade that has been attached to the wind power generation blade. [Effects of the Invention]

[0010] The adhesive sheet for wind power generation blades of the present invention has high adhesion to wind power generation blades, so it can protect the wind power generation blades for a long period of time, and even if it deteriorates, it can be easily peeled off because there is little adhesive residue, and it is also less likely to wrinkle when applied, so the series of operations during repair work can be carried out easily. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic side view showing an example of a base layer included in an adhesive sheet for wind power generation blades of the present invention. FIG. [Figure 2] FIG. 1 is a schematic diagram of a measuring jig used to measure the holding strength of an adhesive sheet for wind power generation blades of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0012]

[0023] In the present specification, the terms "contain" and "comprise" include the concepts of "contain," "comprise," "consist essentially of," and "consist only of."

[0013] 1. Adhesive sheet The adhesive sheet for wind power blades of the present invention (hereinafter simply referred to as the adhesive sheet of the present invention) is an adhesive sheet for bonding to wind power blades, and includes a laminate in which a base layer and an adhesive layer are laminated. The maximum thickness of the base layer is 500 μm or more and 3000 μm or less, the thickness of the adhesive layer is 100 μm or more, and the mass per unit area of ​​the laminate is 1000 g / m 2 is less than.

[0014] The adhesive sheet of the present invention has high adhesion to wind power generator blades and can protect wind power generator blades for a long period of time. Furthermore, even if the adhesive sheet of the present invention deteriorates over a long period of time after being attached to the wind power generator blade, it leaves little adhesive residue and can be easily removed. Moreover, the adhesive sheet of the present invention is less likely to wrinkle when attached, making it suitable for use in repairing wind power generator blades.

[0015] The adhesive sheet of the present invention is also lightweight and therefore easy to work with: the adhesive sheet of the present invention is easy to peel off even when deteriorated, does not wrinkle easily when applied, and is lightweight, making repair work easier and safer than with conventional adhesive sheets, even when working at high altitudes on unstable scaffolding.

[0016] The adhesive sheet of the present invention comprises, as an essential component, a laminate in which a substrate layer and an adhesive layer are laminated.

[0017] (base material layer) The substrate layer is a layer that serves as a substrate for supporting the adhesive layer in the adhesive sheet of the present invention. There are no particular restrictions on the material for constituting the substrate layer, and for example, a wide range of substrates for known adhesive sheets can be applied.

[0018] The substrate layer is preferably formed from a resin. In this case, the adhesive sheet of the present invention tends to be lightweight, the thickness is easy to adjust, wrinkles are less likely to occur when applied, and the erosion resistance of the adhesive sheet is also likely to be improved.

[0019] Examples of resins for forming the base layer include urethane resin, urea resin, polyethylene terephthalate resin, vinyl chloride resin, vinyl acetate resin, acrylic resin, polybutylene terephthalate resin, polyimide, polyether ether ketone, polyetherimide, polyamideimide, polyphenylene sulfide, polycarbonate resin, polystyrene resin, polyethersulfone, acetate resin, and other olefin-based resins (polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer), fluororesins such as polyvinylidene fluoride, and the like.

[0020] In particular, the base layer is preferably formed of a resin containing one selected from the group consisting of urethane resin, urea resin, polyethylene terephthalate resin, vinyl chloride resin, vinyl acetate resin, acrylic resin, and polybutylene terephthalate resin. The urethane resin is preferably a thermoplastic urethane resin (TPU).

[0021] The substrate layer may contain other components in addition to resins, etc. Examples of other components include various components that can be contained in the substrate layer of known adhesive sheets, specifically light stabilizers, antioxidants, preservatives, fillers such as inorganic particles, flame retardants, pigments, colorants, mildew inhibitors, lubricants, etc. One or more of these additives may be contained in the substrate layer.

[0022] The substrate layer may have a single layer structure consisting of only one layer, or may have a laminated structure consisting of two or more layers stacked together, and is preferably a single layer structure.

[0023] The shape of the base layer is not particularly limited. For example, the base layer may be tapered so that the ends are pointed (see Figure 1 below). An adhesive sheet including a base layer with such a shape is likely to have improved aerodynamic characteristics, making it possible to protect the wind turbine blades for a longer period of time.

[0024] FIG. 1 is a schematic side view showing an example of a substrate layer. The substrate layer shown in FIG. 1 has tapered ends. That is, the substrate layer is formed in a convex shape from the ends to the center. Therefore, the thickness D of the center of the substrate layer 1 is greater than the thickness of the end face 1a of the substrate layer 1. Therefore, the thickness D of the center of the substrate layer 1 corresponds to the aforementioned "maximum thickness of the substrate layer." Note that the shape of the substrate layer is not limited to the form shown in FIG. 1. For example, a substrate layer in which the thickness of the end face and the thickness of the center are the same (so-called flat substrate layer) can also be used in the adhesive sheet of the present invention. As mentioned above, in terms of facilitating improved aerodynamic characteristics, it is preferable that the thickness of the center of the substrate layer is greater than the thickness of the end face of the substrate layer, and it is more preferable that the thickness of the center is the maximum thickness.

[0025] As mentioned above, the maximum thickness of the substrate layer is 500 μm or more and 3000 μm or less. This improves the erosion resistance of the adhesive sheet of the present invention, makes it easier to suppress the formation of wrinkles when attached to an object, and also improves sandblasting resistance (sand erosion resistance). Here, the thickness of the substrate layer means the overall thickness of the substrate layer, that is, if the substrate layer has the aforementioned laminated structure, it means the total thickness obtained by adding up the thicknesses of each layer.

[0026] The maximum thickness of the base layer is preferably 550 μm or more, more preferably 600 μm or more, and is preferably 2800 μm or less, more preferably 2500 μm or less, even more preferably 2200 μm or less, and particularly preferably 2000 μm or less. If the maximum thickness of the base layer is less than 500 μm or exceeds 3000 μm, the stiffness of the adhesive sheet decreases and it becomes more likely to wrinkle when applied.

[0027] The thickness of the substrate layer can be measured using a commercially available thickness measuring device. Specifically, the maximum thickness of the substrate layer can be determined by measuring the thickest part of the substrate layer. If it is difficult to determine the thickest part of the substrate layer, for example, the thickness can be measured at 50 points evenly distributed over the entire substrate layer, and the maximum value can be used as the maximum thickness of the substrate layer.

[0028] The method for adjusting the thickness of the base layer is not particularly limited, and for example, any known thickness adjustment method can be widely adopted. When the base layer is obtained by a resin extrusion molding method, the thickness of the base layer can be adjusted by appropriately selecting the extrusion conditions.

[0029] The method for forming the substrate layer is not particularly limited, and for example, a substrate can be formed by the above-mentioned extrusion molding method, and this substrate can be used as the substrate layer of the adhesive sheet. Commercially available substrates can also be used as the substrate layer.

[0030] (adhesive layer) The adhesive layer is the surface that is attached to the object to be repaired (the wind power generation blade), and is the layer that provides the adhesive function to the adhesive sheet.

[0031] The material for forming the adhesive layer is not particularly limited, and for example, a wide variety of known adhesive resins that are known to impart adhesive properties can be applied to the present invention. Examples of adhesive resins for forming the adhesive layer include acrylic resins, polyurethanes, polyolefins, polyesters, rubber-based resins, silicone-based resins, and vinyl acetate-based resins.

[0032] The adhesive layer preferably contains a resin with a glass transition temperature of -25°C or higher and 20°C or lower (i.e., the adhesive resin preferably has a glass transition temperature of -25°C or higher and 20°C or lower). In this case, adhesion to the wind power generation blade is improved, making it possible to protect the wind power generation blade for a longer period of time. More specifically, an adhesive sheet provided with an adhesive containing a resin with a glass transition temperature of -25°C or higher and 20°C or lower is less likely to slip on the wind power generation blade, that is, it is likely to have improved resistance to slippage. Therefore, an adhesive sheet provided with an adhesive layer containing a resin with a glass transition temperature of -25°C or higher and 20°C or lower has excellent holding power to the wind power generation blade. Furthermore, an adhesive sheet provided with an adhesive resin containing a resin with a glass transition temperature of -25°C or higher and 20°C or lower has a relatively high cohesive force of the adhesive layer components, so adhesive residue is likely to be suppressed even if the sheet deteriorates.

[0033] Examples of resins having a glass transition temperature of -25°C or higher and 20°C or lower include the various adhesive resins mentioned above, and among these, acrylic resins are preferred. In this case, the adhesive sheet has better holding power to the wind power generation blades, is less likely to deteriorate, and even if it does deteriorate, adhesive residue is likely to be suppressed.

[0034] In particular, the adhesive sheet of the present invention preferably has a combination in which the base layer is a thermoplastic urethane resin and the adhesive layer is an acrylic resin with a glass transition temperature of −25° C. or higher and 20° C. or lower. In this case, the adhesive sheet has particularly excellent holding power to the wind power generation blades, and is less likely to deteriorate, and even if it does deteriorate, adhesive residue is likely to be suppressed.

[0035] The glass transition temperature is calculated using the following FOX formula: 1 / Tg=W1 / Tg1+W2 / Tg2+ (Tg: glass transition temperature of adhesive resin, W1, W2, ... are the weight fractions of each monomer component in the resin, Tg1, Tg2, ... are the glass transition temperatures of the homopolymers of each monomer component, ) The glass transition temperature of the homopolymer of each component is determined by calculation according to the following formula: The value of the glass transition temperature of the homopolymer of each component is the value described in "Adhesive Technology Handbook" published by Nikkan Kogyo Shimbun or "Polymer Handbook" published by Wiley-Interscience.

[0036] When the resin having a glass transition temperature of -25°C or higher and 20°C or lower is an acrylic resin, the type is not particularly limited, and examples thereof include acrylic polymers having (meth)acrylic acid ester units. In this specification, "(meth)acrylic" means "acrylic" or "methacrylic." For example, "(meth)acrylate" means "acrylate" or "methacrylate."

[0037] Examples of (meth)acrylic acid esters include methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, isopropyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 5-hydroxypentyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, polyalkylene glycol mono(meth)acrylate, etc. The (meth)acrylic acid ester units contained in the acrylic polymer may be of one type or two or more types.

[0038] The weight average molecular weight of the resin contained in the adhesive layer is not particularly limited, and can be, for example, in the same range as that of acrylic resins contained in known adhesive sheets.

[0039] The adhesive layer may have a single layer structure consisting of only one layer, or may have a laminated structure consisting of two or more layers. When the adhesive layer has a laminated structure, the number of layers included in the adhesive layer is not particularly limited, and the adhesive layer may have a two-layer structure or a multi-layer structure consisting of two or more layers. When the adhesive layer has a laminated structure consisting of two or more layers, the layers of the adhesive layer may be the same as each other, or at least one or all of the layers may be different.

[0040] In the adhesive sheet of the present invention, the thickness of the adhesive layer is 100 μm or more, as described above. This allows the adhesive sheet of the present invention to have the desired adhesive strength, easily suppress adhesive residue, and easily become lightweight. Here, the thickness of the adhesive layer refers to the overall thickness of the adhesive layer, that is, if the adhesive layer has the aforementioned laminated structure, it means the total thickness obtained by adding up the thicknesses of each layer. If the adhesive layer has the aforementioned laminated structure, the thickness of each layer is not particularly limited, and the thickness of each layer can be appropriately set so that the total thickness is in the range of 100 μm or more. The thicknesses of each layer of the adhesive layer may be the same or different.

[0041] The thickness of the adhesive layer is preferably 150 μm or more. There is no particular lower limit, but the thicker the layer, the greater the air resistance on the blade. Therefore, from the viewpoint of making it easier to suppress this air resistance, it is desirable that the thickness of the adhesive layer be 500 μm or less.

[0042] The adhesive layer may contain other components in addition to the adhesive resin. For example, the adhesive layer preferably contains an antioxidant. In this case, the adhesive sheet of the present invention is less likely to deteriorate after lamination, adhesive residue is more likely to be suppressed, and peeling is easier.

[0043] The type of antioxidant contained in the adhesive layer is not particularly limited, and a wide variety of known antioxidants can be used, for example. Examples of antioxidants include phenol-based antioxidants, amine-based antioxidants, sulfur-based antioxidants, and phosphorus-based antioxidants. These antioxidants may be used alone or in combination of two or more.

[0044] The content of the antioxidant in the adhesive layer is not particularly limited. The adhesive layer preferably contains 0.1% to 5% by mass of the antioxidant relative to the total mass of the adhesive layer, since this reduces deterioration after the adhesive sheet is bonded and helps to prevent adhesive residue. The content of the antioxidant relative to the total mass of the adhesive layer is more preferably 0.5% by mass or more, more preferably 3% by mass or less, and even more preferably 1% by mass or less.

[0045] In one preferred embodiment of the adhesive layer, the adhesive layer contains a resin with a glass transition temperature of -25°C or higher and 20°C or lower, and contains an antioxidant in an amount of 0.1% by mass or higher and 5% by mass or lower. In this case, the adhesive sheet of the present invention is particularly resistant to deterioration after lamination, adhesive residue is further suppressed, and peeling is particularly easy. In this embodiment, the substrate layer is preferably a thermoplastic urethane resin.

[0046] The adhesive layer may contain other components in addition to the antioxidant described above, for example, silane coupling agents, crosslinking agents, light stabilizers, antioxidants, preservatives, fillers such as inorganic particles, flame retardants, pigments, colorants, anti-fungal agents, etc., as needed.

[0047] The method for forming the adhesive layer is not particularly limited, and any known method can be widely used. For example, the adhesive layer can be formed using an adhesive composition containing a material for forming the adhesive layer. More specifically, the adhesive layer can be formed by applying the adhesive composition to a substrate. In this case, the substrate may be the substrate layer of the adhesive sheet of the present invention.

[0048] The adhesive composition contains, for example, at least a material for forming an adhesive layer. Therefore, the adhesive composition preferably contains the aforementioned resin having a glass transition temperature of -25°C or higher and 20°C or lower, particularly an acrylic resin. In addition to an adhesive resin such as an acrylic resin, the adhesive composition may contain the aforementioned antioxidant as needed, and may also contain other components. The content ratio of the antioxidant, etc. contained in the adhesive composition can be appropriately set depending on the content ratio of the antioxidant contained in the adhesive layer.

[0049] The adhesive composition may contain a solvent to improve application properties. The type of solvent is not particularly limited, and examples of the solvent include hydrocarbons such as hexane, heptane, toluene, and xylene; halogenated hydrocarbons such as dichloromethane; alcohols such as methanol, ethanol, propanol, and isopropyl alcohol; ketones such as acetone and methyl ethyl ketone; and esters such as methyl acetate, ethyl acetate, and butyl acetate.

[0050] The method for applying the adhesive composition to the substrate is not particularly limited, and for example, a wide variety of known application methods can be used. For example, the adhesive layer can be formed using a known application device, such as a bar coater, a gravure coater, a blade coater, an air knife coater, a roll coater, or a die coater.

[0051] A coating film is formed by applying the adhesive composition to a substrate, and the coating film can be cured to form an adhesive layer by subjecting the coating film to a curing treatment, drying treatment, etc. as necessary. The thickness of the coating film is not particularly limited, and can be adjusted by adjusting the application conditions so as to obtain a desired adhesive layer thickness.

[0052] When a substrate layer is used as the substrate, the laminate included in the adhesive sheet of the present invention can be directly obtained by applying the adhesive composition onto the substrate layer.

[0053] (Laminate) The adhesive sheet of the present invention includes a laminate in which a substrate layer and an adhesive layer are laminated. The laminate may consist of only the substrate layer and the adhesive layer, or may include other layers as long as the effects of the present invention are not impaired.

[0054] As mentioned above, the laminate has a mass per unit area of ​​1000 g / m 2 Less than (i.e., 1 kg / m 2 In this case, the adhesive sheet of the present invention is lightweight, making it easier to carry out repair work at high places, for example. The mass per unit area of ​​the laminate is 800 g / m or less. 2 Preferably, it is 500 g / m or less. 2 It is more preferable that the mass per unit area of ​​the laminate is 1000 g / m or less. 2 If this happens, not only will work efficiency decrease, but the holding force will also decrease, making it difficult to protect the wind turbine blades for a long period of time.

[0055] The method for adjusting the mass per unit area of ​​the laminate is not particularly limited, and can be easily adjusted, for example, by changing the thickness of the base layer and adhesive layer that make up the laminate, and the types of materials contained in those layers.

[0056] In the adhesive sheet of the present invention, the stiffness of the laminate is preferably 10 mN / mm or more and 85 mN / mm or less. In this case, the adhesive sheet of the present invention is less likely to wrinkle when applied to the target wind power generation blade, making application easier. The stiffness of the laminate is more preferably 20 mN / mm or more and more preferably 50 mN / mm or less.

[0057] The stiffness value of the laminate can be controlled by adjusting, for example, the thickness of the substrate, the type of material forming the substrate, the thickness of the adhesive layer, the type of adhesive resin for the adhesive layer, and the like.

[0058] (adhesive sheet) The adhesive sheet of the present invention may have other layers as long as it has the laminate as an essential component, or the adhesive sheet of the present invention may consist solely of the laminate.

[0059] For example, the adhesive sheet of the present invention can be provided with a release layer to protect at least one of the adhesive layer and the base layer. Examples of substrates on which the release layer is formed include polyolefin resins such as polyethylene and polypropylene, and polyester resins such as polyethylene terephthalate. Examples of release agents that impart release properties to the release layer include a wide range of known release agents, such as silicone-based release agents and long-chain alkyl group-containing compounds.

[0060] The method for forming the release layer is not particularly limited, and for example, a wide variety of known methods can be employed. Furthermore, the release layer can also be obtained from a commercially available product.

[0061] The adhesive sheet of the present invention is a long sheet, and dimensions such as width and thickness are not particularly limited, and may be the same size as known adhesive sheets, for example.

[0062] The adhesive sheet of the present invention can be in the form of a roll (scroll shape). The form of such a roll is not particularly limited, and for example, the roll may be formed by winding the adhesive sheet of the present invention around a cylindrical core material. That is, the roll is preferably formed by winding the adhesive sheet of the present invention around a cylindrical core material. The type and size of the cylindrical core material in the roll are not particularly limited, and a wide range of known cylindrical core materials can be used. By being formed with the laminate, the adhesive sheet of the present invention is less likely to slip during application, even when used as a roll.

[0063] The type of wind power blade to which the adhesive sheet of the present invention is to be attached is not particularly limited, and examples thereof include a wide range of known wind power blades. The material of the wind power blade is also not particularly limited, and examples thereof include carbon fiber composite materials (CFRP), glass fiber composite materials, etc.

[0064] The adhesive sheet of the present invention is formed using the laminate, and therefore has excellent holding power to wind power generator blades, is less likely to wrinkle when applied, and has excellent conformability to curved surfaces, resulting in excellent repair workability. Furthermore, it is less likely to deteriorate even long periods of time after repair work, and even when peeled off after a long period of time, it leaves little adhesive residue and can be easily peeled off. Therefore, the adhesive sheet of the present invention is suitable for use in repairing wind power generator blades. Furthermore, the adhesive sheet for repairing wind power generator blades of the present invention is lightweight, allowing for easier application even when working at height, resulting in excellent workability.

[0065] 2. Wind turbine blade repair method The adhesive sheet of the present invention can be used to repair wind power generation blades. There are no particular limitations on the method for repairing wind power generation blades using the adhesive sheet. Such a repair method can include, for example, a step R of applying the adhesive sheet of the present invention to the area of ​​the wind power generation blade to be repaired.

[0066] In step R, the method for attaching the adhesive sheet to the area to be repaired is not particularly limited. For example, the sheet may be attached directly by a person, or the attachment work may be performed by a robot or the like.

[0067] When repairing a wind power generation blade, there may be cases where another adhesive sheet (for example, the adhesive sheet of the present invention) has already been attached to the object to be repaired. That is, there may be cases where a deteriorated protective film has already been attached to the wind power generation blade. In this case, the deteriorated protective film (for example, the deteriorated adhesive sheet of the present invention) is peeled off, and then a new adhesive sheet is attached to complete the repair.

[0068] Therefore, the method for repairing a wind power generation blade may include, before step R, step A of peeling off the deteriorated adhesive sheet of the present invention that has already been attached to the wind power generation blade.

[0069] In step A, after the repair sheet is peeled off, the repair area can be cleaned and primed as needed before a new adhesive sheet is attached. The cleaning method and the primer treatment method are not particularly limited, and for example, a wide variety of known methods can be used.

[0070] In step A, if the deteriorated repair sheet is the adhesive sheet of the present invention, as described above, the adhesive sheet of the present invention can be easily peeled off with little adhesive residue, making repair work easier. Therefore, by using the adhesive sheet of the present invention, repeated repair work can be performed easily and simply. If the deteriorated repair sheet is the adhesive sheet of the present invention, the above-mentioned cleaning of the repair area can be omitted, and primer treatment can also be omitted.

[0071] In specifying the inventions included in the present disclosure, the components (properties, structures, functions, etc.) described in the embodiments of the present disclosure may be combined in any manner. In other words, the present disclosure includes all subject matter consisting of all combinations of the components that can be combined as described in this specification. [Example]

[0072] The present invention will be explained in more detail below with reference to examples, but the present invention is not limited to these examples.

[0073] Example 1 A flat substrate layer having a thickness of 600 μm (i.e., a substrate layer having a maximum thickness of 600 μm) was formed using BASF's thermoplastic urethane resin "ET1090." On the other hand, an adhesive layer having a thickness of 150 μm was formed on the substrate layer using an acrylic resin (glass transition temperature 0°C) manufactured by Soken Chemical & Engineering Co., Ltd. A release layer (polyethylene film) was attached to the adhesive layer side of the laminate formed by the resulting substrate layer and adhesive layer to protect the adhesive layer, and this was used as an adhesive sheet.

[0074] Example 2 An adhesive sheet was obtained in the same manner as in Example 1, except that the thermoplastic urethane resin was replaced with a thermosetting urethane resin (TSU) for the base layer.

[0075] Example 3 An adhesive sheet was obtained in the same manner as in Example 1, except that the thermoplastic urethane resin was changed to a vinyl chloride resin for the base layer.

[0076] Example 4 An adhesive sheet was obtained in the same manner as in Example 1, except that the thickness of the base material layer (flat) was changed to 500 μm.

[0077] Example 5 An adhesive sheet was obtained in the same manner as in Example 1, except that the thickness of the base material layer (flat) was changed to 3000 μm.

[0078] Example 6 An adhesive sheet was obtained in the same manner as in Example 1, except that the thickness of the adhesive layer was changed to 100 μm.

[0079] Example 7 An adhesive sheet was obtained in the same manner as in Example 1, except that the acrylic resin forming the adhesive layer was changed to an acrylic resin (glass transition temperature: −25° C.) manufactured by Soken Chemical & Engineering Co., Ltd.

[0080] Example 8 An adhesive sheet was obtained in the same manner as in Example 1, except that the acrylic resin forming the adhesive layer was changed to an acrylic resin (glass transition temperature 20° C.) manufactured by Soken Chemical & Engineering Co., Ltd.

[0081] (Comparative Example 1) An adhesive sheet was obtained in the same manner as in Example 1, except that the thickness of the base material layer (flat) was changed to 300 μm and the thickness of the adhesive layer was changed to 50 μm.

[0082] (Comparative Example 2) An adhesive sheet was obtained in the same manner as in Example 1, except that the thickness of the base material layer (flat) was changed to 5000 μm.

[0083] (Comparative Example 3) A 650 μm thick substrate layer was formed using hydrogenated nitrile rubber (HNBR) from Nippon Zeon Co., Ltd. Separately, a 550 μm thick adhesive layer was formed on the substrate layer using butyl rubber (glass transition temperature: −35°C) from JSR Corporation. A release layer (polyethylene film) was attached to the adhesive layer side of the laminate formed from the resulting substrate layer and adhesive layer to protect the adhesive layer, and this was obtained as an adhesive sheet. obtained.

[0084] Comparative Example 4 An adhesive sheet was obtained in the same manner as in Example 1, except that the acrylic resin forming the adhesive layer was changed to an adhesive (glass transition temperature 50°C) manufactured by Toagosei Co., Ltd.

[0085] (Evaluation method) <Sandblasting test> For the sandblasting test, Fuji Manufacturing's "PNEUMA-BLASTER SGF-4(A)S type" (media: SiC#220, nozzle diameter: Φ0.9mm) was used. The test conditions were as follows: ·Irradiation angle: 90° ·Irradiation amount: 120g / min ·Irradiation distance: 50mm ·Irradiation time: 150sec Irradiation pressure: 0.31 MPa The samples were prepared as follows: The adhesive surface of the adhesive sheet obtained in each Example and Comparative Example was attached to a 2 mm thick GFRP plate that had been gel-coated on one side, and this was used as a test specimen, which was then subjected to sandblasting. The thickness of the center of the test specimen containing this GFRP plate was measured before and after sandblasting, and the difference between the measured values ​​was taken as the amount of thinning, which was evaluated according to the following criteria. ≪Judgment criteria≫ ◯: The difference in thickness before and after treatment was less than 100 μm, and the sandblasting resistance was excellent. △: The difference in thickness before and after treatment was 100 μm or more and less than 1000 μm, and the sandblasting resistance was at an acceptable level. ×: The difference in thickness before and after treatment was 1000 μm or more, and the sandblasting resistance was poor.

[0086] <Holding force measurement> Holding strength measurements were performed in accordance with JIS Z-1528 using the measuring jig shown in Figure 2. Test specimens were prepared by cutting the adhesive sheet to a width of 25 mm and a length of 60 mm. As shown in Figure 2, the adhesive surface 6 of test specimen 5 was attached to a cold-rolled stainless steel plate 7 (SUS304 plate) measuring 2.0 mm thick, 50 mm wide, and 75 mm long, with the test specimen offset in the longitudinal direction so that the adhesive length was 25 mm and the test specimen protruded beyond the edge of the steel plate 7. The specimen was then pressed against the plate using a 2 kg roller, with one reciprocating motion, to prepare a measurement sample. The measurement sample was then left in an atmosphere of 40°C and 50% RH for 60 minutes, after which a 1 kg weight 8 was attached to the measurement sample so that a load was applied in the shear direction in an atmosphere of 40°C. The amount of displacement of the test specimen was measured 1 hour after applying the load with the weight 8, and the holding strength was evaluated based on the following criteria. ≪Judgment criteria≫ ⊚: The amount of deviation was less than 0.5 mm, and excellent holding power was observed. ◯: The amount of deviation was 0.5 mm or more and less than 1.5 mm, and the holding power was at a level that did not pose a problem. △: The amount of deviation was 1.5 mm or more and less than 3.0 mm, and the holding power was at a level that was almost ok. ×: The amount of deviation was 3.0 mm or more, and the holding power was poor.

[0087] <Measurement of margins relative to surface roughness> A test plate for 180° peel measurement was prepared by attaching commercially available sandpaper (#120 and #1200) with double-sided tape (Sekisui #5600 acrylic waterproof tape) face up to a JIS Z-0237 test plate. Using the test plate, a 180° peel test of the adhesive sheet was carried out using the measurement method in accordance with JIS Z-0237. The rate of change of #120 relative to #1200 was measured three times, and the average value of the rate of change was calculated and evaluated based on the following criteria. ≪Judgment criteria≫ ○: The rate of change was less than 10%. △: The rate of change was 10% or more and less than 50%. ×: The rate of change was 50% or more.

[0088] <Body strength (roof stiffness test)> The adhesive sheet was cut into a width of 20 mm and a length of 100 mm to prepare a test piece. Measurements were carried out using a Roof Stiffness Tester DA manufactured by Toyo Seiki Co., Ltd., with a loop length of 60 mm and a speed of 3.3 mm / sec. Compression was performed up to a chuck-indenter distance of 10 mm, and the maximum load was measured as stiffness. The stiffness was evaluated based on the following criteria. ≪Judgment criteria≫ Good: The stiffness was 10 mN / mm or more and less than 85 mN / mm, which was within the appropriate range. ×: The stiffness was less than 10 mN / mm or 85 mN / mm or more, which was in an unsuitable range.

[0089] <Mass per unit area> The pressure-sensitive adhesive sheet was cut into a piece of 100 mm x 100 mm, and the mass was measured using an electronic balance. The measured mass was multiplied by 100 to convert it into weight per square meter, which was taken as the mass per unit area. ≪Judgment criteria≫ 〇:1000g / m 2 The results were below the appropriate range. ×:1000g / m 2 This was the inappropriate range.

[0090] Table 1 shows the layer structure and evaluation results of the adhesive sheets obtained in each Example and Comparative Example. From Table 1, it can be seen that the adhesive sheets obtained in the Examples have a maximum thickness of the base layer of 500 μm or more and 3000 μm or less, a thickness of the adhesive layer of 100 μm or more, and a mass per unit area of ​​the laminate of 1000 g / m 2 Therefore, the adhesive sheet obtained in the examples can protect wind turbine blades for a long period of time, can be easily peeled off even if it deteriorates because there is little adhesive residue, and is less likely to wrinkle when applied, making it easy to carry out the series of repair work.

[0091]

Table 1

Claims

1. An adhesive sheet for attaching to a wind power generation blade, A laminate in which a base layer and an adhesive layer are laminated, The maximum thickness of the base layer is 500 μm or more and 3000 μm or less, The adhesive layer has a thickness of 100 μm or more, The mass per unit area of ​​the laminate is 1000 g / m ２ is less than Adhesive sheet for wind turbine blades.

2. 2. The adhesive sheet for wind power generation blades according to claim 1, wherein the base layer contains at least one resin selected from the group consisting of urethane resin, urea resin, polyethylene terephthalate resin, vinyl chloride resin, vinyl acetate resin, acrylic resin, and polybutylene terephthalate resin.

3. 2. The adhesive sheet for wind power generation blades according to claim 1, wherein the adhesive layer has a glass transition temperature of −25° C. or higher and 20° C. or lower.

4. 2. The adhesive sheet for wind power generation blades according to claim 1, wherein the stiffness of the laminate is 10 mN / mm or more and 85 mN / mm or less.

5. A wound body in which the adhesive sheet for wind power generation blades according to any one of claims 1 to 4 is wound around a cylindrical core material.

6. 5. A method for repairing a wind power generation blade using the adhesive sheet for wind power generation blades according to any one of claims 1 to 4, comprising a step R of attaching the adhesive sheet for wind power generation blades to a location of the wind power generation blade to be repaired.

7. 7. The method for repairing a wind power generation blade according to claim 6, further comprising, before step R, step A of peeling off the deteriorated adhesive sheet for a wind power generation blade that has been stuck to the wind power generation blade.

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