JP6428864B2 - Transparent film and method for producing the same - Google Patents

Description

  The present invention relates to a transparent film exhibiting good weather resistance and antifouling property and a method for producing the same.

  Some recent transparent films include a plastic substrate, an organic layer provided on the plastic substrate, and an inorganic layer provided on the organic layer. The inorganic layer having hydrophilicity plays a role of imparting antifouling properties to the transparent film. When such a transparent film is used outdoors, in addition to high transparency, it is required to have high weather resistance so as not to be deteriorated by irradiation with ultraviolet rays.

  Various transparent films having the above-described configuration have been conventionally proposed. Patent Document 1 discloses a high refractive index layer containing a high refractive index composite oxide fine particle and a matrix, wherein the high refractive index composite oxide fine particle has a titanium element and an oxide having a refractive index of 1.95 or more. And at least one metal ion selected from Co ions, Zr ions, and Al ions in the composite oxide. Techniques for doped high refractive index layers have been proposed.

  Patent Document 2 discloses an antiglare film in which an active ray curable resin layer containing fine particles is provided on a cellulose ester film containing an ultraviolet absorber and two or more plasticizers. As selected from plasticizers other than phosphate ester plasticizers, and the content of phosphate ester plasticizer is less than 1% by mass, and the cellulose ester film has a total acyl group substitution degree of 2.6 to 2.9. Biaxial stretching after casting a cellulose ester solution having a number average molecular weight (Mn) of 80,000 to 200,000 and a weight average molecular weight (Mw) / number average molecular weight (Mn) of 1.4 to 3.0 The actinic radiation curable resin layer is coated with an actinic radiation curable resin containing fine particles on a cellulose ester film, and then irradiated with actinic radiation to cure the actinic radiation. Technology relating antiglare film curing the fat have been proposed.

  In Patent Document 3, in the antireflection film in which the hard coat layer and the antireflection layer are laminated in this order from the base film side on one side of the base film, the average of the hard coat layer before the antireflection layer is laminated. A technique relating to an antireflection film having a surface roughness Ra (nm) satisfying 2.3 ≦ Ra ≦ 4.6 has been proposed.

Patent Document 4 has at least one ceramic layer mainly composed of an oxide, nitride oxide or nitride containing Si or Al on at least one surface of a resin base material containing a light stabilizer, and water vapor transmission rate (JIS K7129-1992 B method, 40 ° C., 90% RH conditions) is a technique related to or less 0.01g ^/ m ^2/24 hours weather resistant resin substrate has been proposed.

JP 2004-271612 A JP 2005-15507 A JP 2005-17707 A WO2009 / 150992 A1 (International pamphlet)

  The recent demand for higher performance is the same for transparent films used outdoors, and it is desired to increase antifouling properties while having the desired weather resistance and transparency. In response to these demands, the techniques proposed in Patent Documents 1 to 4 have a problem that antifouling properties are insufficient as a transparent film used outdoors.

  This invention solves the said subject, The objective is to provide the transparent film which shows favorable weather resistance and antifouling property, and its manufacturing method.

  In order to improve the antifouling property of the transparent film, the present inventor has eagerly investigated the above problems, and has improved the hydrophilicity of the inorganic layer of the transparent film, and the self-purifying property of the transparent film (hereinafter simply referred to as “cleaning property”). Also called “self-cleaning”. In order to improve the hydrophilicity of the inorganic layer of the transparent film, it is necessary to reduce the amount of carbon element contained in the inorganic layer. In order to form such an inorganic layer, the present inventor has attempted to form the inorganic layer with high-energy plasma in the presence of oxygen.

However, when an inorganic layer is formed with high-energy plasma in the presence of oxygen, an inorganic layer with a small amount of carbon element capable of imparting hydrophilicity can be formed. On the other hand, a transparent film after forming the inorganic layer Delamination (so-called “delamination”) occurred between the organic layer and the inorganic layer after the weather resistance test. Specifically, it was confirmed that the organic layer and the inorganic layer were delaminated when irradiated with ultraviolet light or xenon lamp light in a high humidity environment. The present inventor has conducted a thorough analysis of the cause of this problem, and the cause of the problem of delamination between the organic layer and the inorganic layer of the transparent film after the weather resistance test is that the inorganic layer is formed with high-energy plasma in the presence of oxygen. It was estimated that the surface of the organic layer was decomposed by the collision of radicals and ions contained in the plasma. The present inventor has a problem of delamination by forming an organic layer using a cured product of a resin composition containing a urethane acrylate having characteristics that are not easily decomposed by plasma (hereinafter also simply referred to as “plasma resistance”). It was found that can be improved. Specifically, the arithmetic average roughness of the surface after performing plasma irradiation with oxygen gas at an output of 300 W / sccm for 15 minutes on the surface having an arithmetic average roughness (Ra) of 15 nm or less is the surface before the plasma irradiation. It was found that the problem of delamination between the organic layer and the inorganic layer of the transparent film after the weather resistance test can be improved by using an organic layer having an arithmetic average roughness of 12 times or less.

  However, even with a transparent film having such an organic layer, the organic layer and the inorganic layer may delaminate after the weather resistance test. The present inventor has further studied diligently and found that such delamination can be prevented by increasing the degree of curing of the organic layer, and has completed the present invention.

A transparent film according to the present invention for solving the above-mentioned problems has a plastic substrate, an organic layer provided on the plastic substrate, and an inorganic layer provided on the organic layer, and the organic film The layer is a cured product of a resin composition containing urethane acrylate, and has a weight reduction rate (hereinafter referred to as “immersion weight reduction rate”) of 6% or less after the organic layer is immersed in methyl ethyl ketone for 24 hours. and, the Ra of the surface after performing JIS B0601 in accordance with the arithmetic mean roughness was measured by the method (2001) (Ra) is 15 minutes plasma irradiation with oxygen gas to the surface is 15nm or less at an output 300 W / sccm The Ra before irradiation with the plasma is 12 times or less, and the inorganic layer has a contact angle with water of 40 ° or less.

According to this invention, since the organic layer is a cured product of the resin composition containing urethane acrylate, the organic layer exhibits high weather resistance. Moreover, since the organic layer has an immersion weight reduction rate of 6% or less, it becomes an organic layer having a high degree of curing. Furthermore, the organic layer, Ra of the surface after the arithmetic average roughness (Ra) was performed 15 min plasma irradiation with oxygen gas to the surface is 15nm or less at an output 300 W / sccm is, before the plasma irradiation of Ra Since it is 12 times or less, the organic layer exhibits high plasma resistance. As a result, even when the inorganic layer is formed under conditions that can impart hydrophilicity, that is, when the inorganic layer is formed on the organic layer with high-energy plasma in the presence of oxygen, the decomposition of the organic layer is suppressed. Therefore, it is possible to prevent delamination of the organic layer and the inorganic layer after the weather resistance test. According to such a transparent film of the present invention, good antifouling properties and weather resistance can be exhibited.

  In the transparent film according to the present invention, the organic layer preferably contains a weathering agent.

  According to this invention, since the organic layer contains a weathering agent, the weather resistance of the organic layer is improved. As a result, good weather resistance can be imparted to the transparent film of the present invention.

  In the transparent film according to the present invention, the inorganic layer is one or more inorganic compounds selected from metal oxide, metal nitride, metal carbide, metal oxycarbide, metal carbonitride, and metal oxynitride carbide It is preferable that

  According to this invention, the inorganic layer is one or more inorganic compounds selected from metal oxides, metal nitrides, metal carbides, metal oxycarbides, metal carbonitrides, and metal oxynitride carbides. High hydrophilicity can be imparted to the inorganic layer. Such a transparent film of the present invention can exhibit good antifouling properties.

  In the transparent film according to the present invention, the organic layer is preferably a cured product of an electron beam curable resin composition.

  According to this invention, since the organic layer is a cured product of the electron beam curable resin composition, the organic layer has a high degree of curing. Therefore, since the organic layer exhibits high plasma resistance, it is possible to prevent the organic layer from being decomposed even when the inorganic layer is formed on the organic layer with high energy plasma. As a result, the organic layer and the inorganic layer can be prevented from delamination after the weather resistance test, so that the transparent film of the present invention exhibits good antifouling properties and weather resistance.

The method for producing a transparent film according to the present invention for solving the above problems includes a step of applying a resin composition containing urethane acrylate on a plastic substrate, and a step of curing the resin composition to form an organic layer. And an organic layer having a step of forming an inorganic layer on the organic layer, the organic layer having an immersion weight reduction rate of 6% or less, and an arithmetic average measured by a method according to JIS B0601 (2001) The surface of the surface having a roughness (Ra) of 15 nm or less is irradiated with plasma with oxygen gas at an output of 300 W / sccm for 15 minutes, and the Ra of the surface is 12 times or less of Ra before the plasma irradiation. The inorganic layer has a contact angle with water of 40 ° or less.

According to this invention, since it has the process of apply | coating the resin composition containing urethane acrylate and the process of hardening the said resin composition and forming an organic layer, an organic layer shows high weather resistance. Moreover, since the immersion weight reduction | decrease rate of an organic layer is 6% or less, it becomes an organic layer with a high hardening degree. In addition, when the organic layer has a surface with an arithmetic average roughness (Ra) of 15 nm or less and plasma irradiation with oxygen gas is performed at an output of 300 W / sccm for 15 minutes, the surface Ra is the Ra before the plasma irradiation. Since it is 12 times or less, it becomes an organic layer with high plasma resistance. As a result, even when the inorganic layer is formed under conditions that can impart hydrophilicity, that is, when the inorganic layer is formed on the organic layer with high-energy plasma in the presence of oxygen, the organic layer is decomposed. Therefore, it is possible to prevent delamination of the organic layer and the inorganic layer after the weather resistance test. According to such a method for producing a transparent film of the present invention, a transparent film exhibiting good antifouling properties and weather resistance can be produced.

  In the method for producing a transparent film according to the present invention, the inorganic layer is preferably formed by a plasma chemical vapor deposition method or an ion plating method.

  According to the transparent film of the present invention, since the organic layer exhibits high weather resistance and plasma resistance, even when an inorganic layer is formed on the organic layer with high energy plasma in the presence of oxygen, It is possible to prevent delamination between the organic layer and the inorganic layer. Moreover, an inorganic layer shows high hydrophilicity. As a result, good antifouling properties and weather resistance can be exhibited.

  According to the method for producing a transparent film of the present invention, since the organic layer exhibits high weather resistance and plasma resistance, the organic layer and the inorganic layer are formed even when the inorganic layer is formed on the organic layer with high energy. It is possible to prevent delamination between layers. Moreover, an inorganic layer shows high hydrophilicity. As a result, a transparent film showing good antifouling properties and weather resistance can be produced.

It is typical sectional drawing which shows an example of the transparent film which concerns on this invention. It is typical sectional drawing which shows the other example of the transparent film which concerns on this invention.

  Hereinafter, embodiments of the present invention will be described in detail. The present invention is not limited to the following embodiments, and various modifications can be made within the scope of the gist thereof.

[Transparent film]
As shown in FIG. 1, the transparent film 10 according to the present invention includes a plastic substrate 1, an organic layer 2 formed on the plastic substrate 1, and an inorganic layer 3 formed on the organic layer 2. . The organic layer 2 is a cured product of a resin composition containing urethane acrylate, and has a weight reduction rate (hereinafter referred to as “ immersion weight reduction rate ”) of 6 after the organic layer is immersed in methyl ethyl ketone for 24 hours . %, And the surface of the organic layer 2 whose arithmetic average roughness (Ra) measured by a method according to JIS B0601 (2001) is 15 nm or less is subjected to plasma irradiation with oxygen gas for 15 minutes at an output power of 300 W / sccm. The Ra after the surface is 12 times or less the Ra before the plasma irradiation, and the inorganic layer 3 is characterized in that the surface contact angle with water is 40 ° or less.

  According to such a transparent film 10, since the organic layer 2 exhibits high weather resistance and plasma resistance, even when the inorganic layer 3 is formed on the organic layer 2 with high energy, the organic layer 2 and the inorganic layer 3 can be prevented from delamination. Moreover, the inorganic layer 3 shows high hydrophilicity. As a result, good antifouling properties and weather resistance can be exhibited.

  The reason why the transparent film 10 has good antifouling property is due to the following intensive studies by the present inventors. That is, the present inventor has proposed that the hydrophilicity of the inorganic layer 3 is further improved and the self-cleaning property of the transparent film 10 is improved, and as a result, good antifouling property is exhibited. In order to form the more hydrophilic inorganic layer 3, the present inventor has proposed to reduce the amount of carbon element contained in the inorganic layer 3, and for that purpose, the inorganic layer is formed under conditions that can impart hydrophilicity. It was proposed to form the inorganic layer 3 with high energy plasma in the presence of oxygen.

However, when the inorganic layer 3 is formed with high-energy plasma in the presence of oxygen, the inorganic layer 3 with a small amount of carbon element capable of imparting hydrophilicity can be formed. The transparent film 10 had a problem that the weather resistance was lowered because delamination between the organic layer 2 and the inorganic layer 3 occurred in the weather resistance test. Specifically, it was confirmed that such delamination occurred when irradiated with ultraviolet light or xenon lamp light in a high humidity environment. The present inventor has diligently analyzed the cause of this problem, and the reason why such delamination occurs in the transparent film 10 is that the organic layer 2 is formed by forming the inorganic layer 3 with high energy plasma in the presence of oxygen. It was estimated that it was due to decomposition. Therefore, the present inventor has devised to improve the plasma resistance of the organic layer 2, and as a result of intensive studies, by forming the organic layer 2 having a high degree of curing using urethane acrylate having a high plasma resistance, It has been found that such a problem that the delamination occurs and the weather resistance decreases can be solved. Specifically, as the urethane acrylate, the organic layer 2 formed with the urethane acrylate is subjected to plasma irradiation with oxygen gas for 15 minutes at an output of 300 W / sccm on the organic layer 2 having an arithmetic average roughness (Ra) of 15 nm or less. By using a material whose arithmetic average roughness after the surface is 12 times or less of the arithmetic average roughness of the surface before the plasma irradiation, and further increasing the degree of cure of the organic layer 2, The present inventors have found that the problem of delamination can be solved and completed the present invention.

  The organic layer 2 and the inorganic layer 3 of the transparent film 10 are at least provided in that order on one surface S1 of the plastic substrate 1 as shown in FIG. 1, but although not shown, the organic layer 2 is also formed on the other surface S2. And the inorganic layer 3 may be provided in that order. Moreover, as shown in FIG. 1, neither the organic layer 2 nor the inorganic layer 3 need be provided on the other surface S2. In addition, the transparent film 10 may be appropriately provided with other functional layers between the plastic substrate 1 and the organic layer 2 or on the inorganic layer 3 according to applications. Other functional layers include, for example, primer layers, easy adhesion layers, matting agent layers, protective layers, antistatic layers, smoothing layers, adhesion improving layers, light shielding layers, antireflection layers, hard coat layers, stress relaxation layers, Examples include an antifogging layer, an antifouling layer, and a printing layer.

  As shown in FIG. 1, the transparent film 10 may be formed of a flat organic layer 2 and an inorganic layer 3, or the transparent film 10 </ b> B shown in FIGS. 2A, 2 </ b> B, and 2 </ b> C. Like C and D, you may form with the organic layer 2 with an uneven | corrugated shape. The transparent film 10B is an example in which a plurality of triangular or substantially triangular cross-sectional shapes 4 constituting a unit prism are formed on one surface S1 of the plastic substrate 1. Such a concavo-convex shape 4 is formed of the organic layer 2 and the inorganic layer 3 having the concavo-convex shape 4, and can impart a prism function for collecting, deflecting, or directing incident light. Examples of such unit prisms include those in which a large number of unit prisms having ridge lines at the top are arranged in parallel in a direction perpendicular to the ridge lines. The cross-sectional shape of the unit prism is not limited to a triangle or a substantially triangular shape, but a curvature such as a polygon such as a quadrangle, pentagon, hexagon, or octagon, a curve such as a circle, an ellipse, or a sine curve, or a sector or a triangle. A combination shape of a straight line and a curve, such as the provided shape, can be appropriately used according to desired optical characteristics. In addition, the arrangement of unit prisms in a plane is made by arranging polyhedrons, hemispheres, etc. in a two-dimensional direction (vertical and horizontal directions) in addition to a one-dimensional arrangement (linear arrangement) in which columnar bodies are arranged in a one-dimensional direction. A dimensional array (typical example is an eyelet lens) can also be used. The angle of the top of the unit prism is not particularly limited, and is, for example, 80 ° or more and 110 ° or less. Further, the pitch of the unit prisms 4 arranged is not particularly limited, and is, for example, about 10 μm or more and 300 μm or less.

  The transparent film 10 </ b> C is an example in which an uneven shape 5 having a Fresnel lens shape is formed on one surface S <b> 1 of the plastic substrate 1. Such a concavo-convex shape 5 is formed of the organic layer 2 and the inorganic layer 3 having the concavo-convex shape 5, and can provide a function of a Fresnel lens that condenses incident light. The concavo-convex shape 5 may be formed in a hemispherical convex lens, or may be formed in each lens by arranging a plurality of semicylindrical (so-called “kamaboko”) lenses. . Although not shown, the transparent film 10 may have a lenticular lens-shaped uneven shape on one surface of the plastic substrate 1 and impart the function of a lenticular lens that diffuses incident light.

  The transparent film 10D is an example in which an organic layer 2 having a concavo-convex shape is provided on one surface S1 of a plastic substrate 1, and a functional part 6 is formed by filling a functional material into the concavo-convex recess. The layer 3 is formed flat on the organic layer 2 having an uneven shape and the functional part 6. The functional part 6 is not particularly limited, and examples thereof include a heat ray absorbing part that absorbs heat rays and a heat ray reflecting part that reflects heat rays. The angle θ formed by the side surface of the concave and convex portion provided in the organic layer 2 and the line P perpendicular to the surface of the transparent film 10D is not particularly limited, and is, for example, 0 ° or more and 15 ° or less. . When this angle θ is 0 °, the cross-sectional shape of the functional part 6 is rectangular. When the angle θ exceeds 0 °, the cross-sectional shape of the functional part 6 has a trapezoidal shape in which the two bottom sides are parallel to the surface of the transparent film 10D, and the organic layer 2 is formed on the two bottom sides. The one located at the bottom of the concave-convex shape is shorter. Such a transparent film 10D, for example, can give the organic layer 2 a function as a prism that transmits sunlight, and can fill the functional part 6 with a material that absorbs heat rays to give a function as a heat ray absorbing part. It can be preferably used as a functional film for the purpose of heat ray control.

  Below, the component of the transparent film 10 is demonstrated in more detail.

<Plastic base material>
The plastic substrate 1 is not particularly limited as long as it can form the organic layer 2 and has transparency, but a polyester-based resin can be preferably mentioned from the viewpoint of actual use. Examples of the polyester resin include polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), copolymers thereof, and polycyclohexanedimethylene terephthalate (PCT). Among the polyester resins, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and copolymers thereof are preferable. Particularly preferably, the plastic substrate 1 is a polyethylene naphthalate film or a polyethylene terephthalate film.

  If a resin uniaxially stretched film or a biaxially stretched film is used, the plastic substrate 1 having both high transparency and mechanical strength can be obtained. Among these, a biaxially stretched film of polyethylene terephthalate is preferable in terms of heat resistance, mechanical strength, light transmittance, cost, and the like.

  When a polyester-based resin is applied as the material of the plastic substrate 1, the whole may be a film-like substrate made of a polyester-based resin, or the side on which the organic layer 2 is formed (one side S <b> 1 or FIG. 1 in FIG. 1). 2 may be a film-like laminated base material in which at least a polyester-based resin layer is formed on both surfaces S1, S2). In this film-like laminated substrate, layers other than the polyester resin layer on which the organic layer 2 is formed may not be a polyester resin layer. In selecting a layer type other than the polyester-based resin layer, various resin layers are arbitrarily selected in consideration of heat resistance, thermal expansion, light transmittance, and the like.

  The thickness of the plastic substrate 1 is not particularly limited, but is preferably about 10 μm or more and 500 μm or less. Moreover, since the transparent base material 10 is used for the use as which the transparency is requested | required, it is preferable to select the plastic base material 1 whose total light transmittance is 80% or more.

  The surface of the plastic substrate 1 may be subjected to surface treatment such as corona treatment, flame treatment, plasma treatment, glow discharge treatment, roughening treatment, heat treatment, chemical treatment, and easy adhesion treatment as necessary. . As a specific method of such surface treatment, a conventionally known method can be appropriately used. Moreover, you may provide another functional layer in the surface where the organic layer 2 is not directly formed. Examples of functional layers include matting agent layers, protective layers, antistatic layers, smoothing layers, adhesion improving layers, light shielding layers, antireflection layers, hard coat layers, stress relaxation layers, antifogging layers, antifouling layers, coatings. A printing layer, an easily bonding layer, etc. are mentioned.

<Organic layer>
The organic layer 2 is provided on the plastic substrate 1 and is formed of a cured product of a resin composition containing urethane acrylate. As the characteristics, the surface after the immersion weight reduction rate is 6% or less and the arithmetic average roughness (Ra) is 15 nm or less and plasma irradiation with oxygen gas is performed at an output of 300 W / sccm for 15 minutes. Is 12 times or less of the arithmetic average roughness of the surface before plasma irradiation.

  The urethane acrylate that forms the organic layer 2 is a monomer oligomer and prepolymer of urethane acrylate, and is not particularly limited as long as the cured product has transparency and high plasma resistance. Examples of commercially available products include UV7000-B (manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) and UV-7510B (manufactured by Nippon Synthetic Chemical Industry Co., Ltd.), and the like. Other types of effects can be mentioned. These may be used individually by 1 type and may be used in combination of 2 or more type. In this specification, “urethane acrylate” includes urethane methacrylate, “acrylate” includes methacrylate, and “acryloyl group” includes methacryloyl group.

  The organic layer 2 has an immersion weight reduction rate of 6% or less. For example, after the inorganic layer 3 is removed from the transparent film 10, the plastic substrate 1 and the organic layer 2 are cut into appropriate sizes, and these are reduced to methyl ethyl ketone (MEK) at room temperature. It can be calculated from the rate of weight loss after soaking for 24 hours. Here, since the plastic substrate 1 normally does not contain any components that elute in MEK, the plastic substrate 1 and the organic layer 2 are eluted in MEK for 24 hours by immersing them in MEK at room temperature. The component to be used is only the uncured component in the organic layer 2. Therefore, since the weight reduction rate of the plastic substrate 1 and the organic layer 2 can be converted into the weight reduction rate of only the organic layer 2, the immersion weight reduction rate (%) of the organic layer 2 can be calculated. The weight of the organic layer 2 can be obtained by subtracting the weight of the plastic substrate 1 from the total weight of the plastic substrate 1 and the organic layer 2, and the weight of the plastic substrate 1 is determined by the plastic substrate 1 You can calculate from one type. Specifically, the type of the plastic substrate 1 can be specified, and the weight of the plastic substrate 1 can be calculated from the specific gravity of the plastic substrate 1. The type of the plastic substrate 1 can be specified by measuring, for example, infrared spectroscopy or hardness. Moreover, as a method of removing the inorganic layer 3 from the transparent film 10, the method of immersing the transparent film 10 in a 10 mass% concentration hydrofluoric acid for 10 minutes at room temperature and dissolving the inorganic layer 3 can be mentioned, for example.

  The inventor has found that the plasma resistance of the organic layer 2 is improved by reducing the immersion weight reduction rate of the organic layer 2 to 6% or less. The reason for this is not clear at this stage, but it is considered that the organic layer 2 having a dip weight reduction rate of 6% or less has few uncured components in the organic layer 2 and is cured at a high degree of curing. It is done. That is, it is considered that the organic layer 2 cured at a high degree of cure has a high cross-link structure formed at a high density and thus has improved physical durability against plasma.

Furthermore, according to the study of the present inventors, the plasma resistance of the cured product of urethane acrylate is that the cured product is irradiated with plasma with oxygen gas, and the arithmetic average roughness (Ra) of the surface before and after plasma irradiation is increased. It has been found that the amount can be evaluated by calculating the amount, and it has been found that a lower increase is preferable because the plasma resistance is higher. Specifically, the arithmetic average roughness of the surface after plasma irradiation with oxygen gas at an output of 300 W / sccm for 15 minutes is performed on the surface having an initial arithmetic average roughness (Ra) of 15 nm or less. The arithmetic average roughness of the previous surface is preferably 12 times or less. Since the organic layer 2 formed of a cured product of the resin composition containing urethane acrylate has high plasma resistance, even if the inorganic layer 3 is formed with high energy plasma in the presence of oxygen, The organic layer 2 and the inorganic layer 3 can be prevented from delamination. As a result, the transparent film 10 can exhibit good weather resistance and antifouling properties. In addition, although it is not clear at this stage, it is thought that it is based on the chemical structure of urethane acrylate as a reason for the tolerance with respect to the plasma by the oxygen gas of the hardened | cured material depending on the kind of urethane acrylate. Moreover, the lower limit value of the Ra value of the initial organic layer 2 is not particularly limited, but it is 0.1 nm for the sake of convenience.

  Arithmetic average roughness (Ra) is obtained by removing the inorganic layer 3 from the transparent film 10 and then exposing the exposed surface of the organic layer 2 with, for example, a scanning probe microscope (manufactured by SII Nanotechnology Inc., product name: Nano It can be measured by a method according to JIS B0601 (2001) using a cute) or surface roughness measuring instrument (trade name: Handy Surf E-35A, manufactured by Tokyo Seimitsu Co., Ltd.).

  Examples of the method for removing the inorganic layer 3 from the transparent film 10 include a method in which the inorganic layer 3 is dissolved by dipping in 10% by mass hydrofluoric acid for 10 minutes at room temperature. Moreover, the organic layer 2 from which the inorganic layer 3 has been removed by such a method usually has a surface arithmetic average roughness (Ra) of 15 nm or less. Further, even when the arithmetic average roughness of the surface of the initial organic layer 2 exceeds 15 nm, for example, the surface can be smoothed by dissolving or etching the organic layer 2 with an organic alkaline solution. The arithmetic average roughness of the surface of the initial organic layer 2 can be made 15 nm or less.

  The organic layer 2 is formed of a cured product of a resin composition containing urethane acrylate, but may contain a cured product of a resin other than urethane acrylate. Such a resin is not particularly limited as long as it is a radical polymerizable resin that can be crosslinked by irradiation with ionizing radiation. For example, radical polymerizable such as acrylate group, vinyl group, allyl group, isopropenyl group, etc. One type or two or more types selected from monomers having an unsaturated group (monomers), oligomers and prepolymers can be mentioned. Examples of such oligomers and prepolymers include one or more selected from urethane acrylate, epoxy acrylate, polyester acrylate, polyether acrylate, polyethylene acrylate, polybutadiene acrylate, silicone acrylate, polyol acrylate, and the like. The ionizing radiation is an electron beam and an ultraviolet ray, an electromagnetic wave such as a visible ray, an X ray and a γ ray, and a charged particle beam such as an α ray. The ionizing radiation curable resin is irradiated with an ionizing radiation. This is a resin that crosslinks and cures.

  Examples of the monomer having a radical polymerizable unsaturated group include monofunctional monomers and polyfunctional monomers. Although it does not specifically limit as a monofunctional monomer, For example, vinyl monomers, such as N-vinyl pyrrolidone, N-vinyl caprolactone, vinyl imidazole, vinyl pyridine, styrene; Phenoxyethyl acrylate, lauryl acrylate, stearyl acrylate, butoxyethyl acrylate, Acrylate monomers such as methoxypolyethylene glycol acrylate, tetrahydrofurfuryl acrylate, isobornyl acrylate, isooctyl acrylate, cyclohexyl acrylate, benzyl acrylate, N, N-dimethylacrylamide, N, N-dimethylaminopropyl acrylate, acryloylmorpholine; and acrylamide Derivatives. Polyfunctional monomers include pentaerythritol triacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, polyethylene glycol diacrylate, tripropylene glycol diacrylate, polypropylene glycol diacrylate, polytetramethylene glycol diacrylate, butane Diol diacrylate, hexanediol diacrylate, nonanediol diacrylate, pentanediol diacrylate, neopentyl glycol diacrylate, dimethylol-tricyclodecane diacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, and the like Modified ethylene oxide, B propylene oxide-modified products, and caprolactam modified products and the like. These monomers may be used alone or in combination of two or more. Moreover, the oligomer produced | generated by combining such a monomer may be sufficient.

  The above-mentioned monomers, oligomers and prepolymers may be used alone or in combination of two or depending on the required performance or industrial productivity. Alternatively, two or more kinds can be used in appropriate combination.

  The organic layer 2 preferably contains a weathering agent. The anti-mold agent is for suppressing the occurrence of photo-oxidation degradation by irradiating the organic layer 2 with ultraviolet rays or the like from the outside. Therefore, since the weather resistance of the organic layer 2 can be improved, it becomes the transparent film 10 which shows favorable weather resistance. Specific examples of the weathering agent include an ultraviolet absorber and a hindered amine light stabilizer.

  The ultraviolet absorber is for absorbing and shielding ultraviolet rays contained in natural light or the like. The ultraviolet absorber is not particularly limited as long as such an object can be achieved, and conventionally known ones can be used. For example, a triazine ultraviolet absorber, a benzophenone ultraviolet absorber, a salicylate ultraviolet absorber, an acrylonitrile ultraviolet absorber, and the like can be given. Among them, a triazine-based ultraviolet absorber that has a high ultraviolet-absorbing ability and hardly deteriorates even with high energy such as ultraviolet rays can be given. Specific examples of the triazine ultraviolet absorber include 2- (4,6-diphenyl-1,3,5-triazin-2-yl) -5-[(hexyl) oxy] phenol, 1,3,5 -Triazine-2,4,6 (1H, 3H, 5H) -trione, 1,3,5-tri [{3,5-bis- (1,1-dimethylethyl) -4-hydroxyphenyl} methyl] and A benzotriazole type ultraviolet absorber etc. can be mentioned. Specific examples of the benzotriazole ultraviolet absorber include 2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- (2-hydroxy-3,5-di-tert-amylphenyl) benzotriazole, Examples include 3- [3- (benzotriazol-2-yl) -5-tert-butyl-4-hydroxyphenyl] propionic acid ester of polyethylene glycol.

  Although content in the organic layer 2 of a ultraviolet absorber is not specifically limited, It is preferable to contain 0.1 to 10 mass% in the organic layer 2, Preferably it contains 1 to 5 mass% More preferably. When the ultraviolet absorber is contained in the organic layer 2 by 0.1% by mass or more and 10% by mass or less, the transparent film 10 showing better weather resistance is obtained.

  The hindered amine light stabilizer (HALS) is for catalytically capturing and stabilizing free radicals that cause an oxidation reaction in the organic layer 2. The hindered amine light stabilizer is not particularly limited as long as such an object can be achieved, and a conventionally known one can be used. For example, 2- (3,5-di-tert-butyl-4-hydroxybenzyl) -2′- n-Butylmalonate bis (1,2,2,6,6-pentamethyl-4-piperidyl), bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, bis (1,2, 2,6,6-pentamethyl-4-piperidinyl) sebacate, methyl (1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate, 2,4-bis [N-butyl-N- (1-cyclohexyl) Oxy-2,2,6,6-tetramethylpiperidin-4-yl) amino] -6- (2-hydroxyethylamine) -1,3,5-triazine), tetrakis (2,2, , 6-tetramethyl-4-piperidyl) -1,2,3,4-butane tetracarboxylate, mention may be made of 1,2,2,6,6-pentamethyl-4-piperidinyloxy methacrylate.

  Although content in the organic layer 2 of a hindered amine light stabilizer is not specifically limited, It is preferable to contain 0.5 mass% or more and 10 mass% or less in the organic layer 2, 1 mass% or more, 5 mass% It is more preferable to contain the following. When the hindered amine light stabilizer is contained in the organic layer 2 in an amount of 0.5% by mass or more and 10% by mass or less, the transparent film 10 showing better weather resistance is obtained.

  A reactive weathering agent having a reactive functional group such as an acryloyl group in the molecule can also be used as the above-mentioned weathering agent. Examples of such reactive weathering agents include reactive ultraviolet absorbers and reactive hindered amine light stabilizers. Etc. Examples of the reactive ultraviolet absorber include (2-hydroxy-4- (methacryloyloxyethoxy) benzophenone) methyl methacrylate copolymer. Examples of the reactive hindered amine light stabilizer include 1,2,2,6,6-pentamethyl-4-piperidinyl methacrylate.

  By containing the reactive weathering agent in the organic layer 2, the reactive weathering agent is bonded to the resin in the resin composition via the reactive functional group, so that the reactive weathering agent bleeds on the surface of the organic layer 2. It can be suppressed from going out. Therefore, it is considered that the weathering agent in the organic layer 2 can be prevented from decreasing with time due to bleed-out. Further, it is possible to prevent a decrease in adhesion between the organic layer 2 and the inorganic layer 3 due to precipitation of a weathering agent between the organic layer 2 and the inorganic layer 3. As a result, it is possible to suppress the weather resistance of the transparent film 10 from decreasing with time due to external ultraviolet irradiation or the like, so that the transparent film 10 having good weather resistance is obtained.

  The release agent is not an essential component, but is preferably included in the organic layer 2 when the organic layer 2 has an uneven shape as shown in FIG. Examples of the release agent include a silicone release agent, a fluorine release agent, and a phosphoric acid release agent. Among these, a phosphoric acid type release agent is more preferable. Examples of the phosphoric acid release agent include a phosphoric acid release agent and a phosphoric acid ester release agent. Examples of the phosphoric acid release agent include 1-phenyl-2-phospholene-1-oxide, 3- Phosphorenes such as methyl-2-phospholene-1-oxide, 1-ethyl-2-phospholene-1-oxide, 3-methyl-1-phenyl-2-phospholene-1-oxide, and their 3-phospholene isomers Examples thereof include one or more selected from oxides; triphenylphosphine, tris- (2,4-di-t-butylphenyl) phosphite, brominated tetraethylphosphine, chlorinated tetraethylphosphine, and the like. Phosphoric ester release agents include di-2-ethylhexyl hydrogen phosphite, dilauryl hydrogen phosphite, dialkyl hydrogen phosphite, dioleyl hydrogen phosphite, triisooctyl phosphite, diphenylisodecyl phosphite. One selected from phyto, phenyl diisodecyl phosphite, triisodecyl phosphite, trialkyl phosphite, trioleyl phosphite, tristearyl phosphite, trilauryl trithiophosphite, methyl acid phosphate and ethyl acid phosphate Two or more can be mentioned.

  The release agent is preferably contained in the organic layer 2 in an amount of 0.01% by mass to 20% by mass, more preferably 0.01% by mass to 10% by mass, and 0.01% by mass. More preferably, the content is 5% by mass or less.

  When the organic layer 2 is a cured product obtained by curing the resin composition by ultraviolet irradiation, it contains a photopolymerization initiator. Although it does not specifically limit as a photoinitiator, For example, an acetophenone type compound, an acyl phosphine oxide type compound, etc. can be mentioned. Examples of acetophenone compounds include acetophenone, hydroxyacetophenone, aminoacetophenone, 1-hydroxycyclohexyl phenyl ketone, oligo [2-hydroxy-2-methyl-1- {4- (1-methylvinyl) phenyl} propanone], 2 -Methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1 and the like can be mentioned. Examples of the acyl phosphine oxide compound include bis (2,4,6-trimethylbenzoyl) -phenyl phosphine oxide. 1 type may be used for such a photoinitiator and it may use it in combination of 2 or more types. Moreover, it is preferable that the compounding quantity of a photoinitiator is 0.1 to 5 mass% with respect to the whole quantity of the composition for organic layer formation. In addition, as a quantification method of the weathering agent in the organic layer 2, a mold release agent, and a photoinitiator, it can obtain | require by a gas chromatography mass spectrometry, for example.

  The organic layer 2 is preferably a cured product of an electron beam curable resin composition obtained by curing the resin composition by electron beam irradiation. Since the organic layer 2 is a cured product of the electron beam curable resin composition, the organic layer 2 has a higher degree of curing, so that the transparent film 10 can exhibit higher weather resistance.

  Whether the organic layer 2 is a cured product of an electron beam curable resin composition or, for example, a cured product of an ultraviolet curable resin composition, both are cured products of an ionizing radiation curable resin composition. Therefore, it is generally difficult to specify. However, for example, in order to cure the electron beam curable resin composition, a polymerization initiator such as a photopolymerization initiator is not necessary. Therefore, the cured product of the electron beam curable resin composition usually contains a polymerization initiator. Absent. On the other hand, in order to cure the ultraviolet curable resin composition, a photopolymerization initiator is usually required. Therefore, the cured product of the ultraviolet curable resin composition contains a photopolymerization initiator. Therefore, when the organic layer 2 is formed of a cured product of an ionizing radiation curable resin composition and the organic layer 2 does not contain or substantially does not contain a polymerization initiator, the organic layer 2 is electron beam curable. It can be said that it is a cured product of the resin composition. Further, when the organic layer 2 is formed of a cured product of an ionizing radiation curable resin composition, and the organic layer 2 contains, for example, more than 0.1% by mass of a photopolymerization initiator, the organic layer 2 Can be said to be a cured product of the ultraviolet curable resin composition. Examples of the method for quantifying the polymerization initiator in the organic layer 2 include gas chromatography mass spectrometry.

  Additives may be added to the organic layer 2 as necessary within a range not impairing the effects of the present invention. Examples of the additive include a heat stabilizer, an antifoaming agent, a leveling agent, a plasticizer, a surfactant, an antistatic agent, an antioxidant, an ultraviolet absorber, an infrared absorber, a pigment (colored dye, colored pigment), Examples include extender pigments, light diffusing agents, and coupling agents.

  The thickness of the organic layer 2 is preferably 0.1 μm or more and 100 μm or less from the viewpoint of the deflection of the substrate, regardless of whether it is a single layer or two or more layers. More preferably, it is 5 μm or more and 60 μm or less. In addition, the thickness of the organic layer 2 represents the value of the location where the thickness of the organic layer 2 becomes the maximum.

<Inorganic layer>
The inorganic layer 3 has hydrophilicity and is formed on the organic layer 2 as a functional layer having antifouling and self-cleaning functions. Examples of the material for forming the inorganic layer 3 include one or more inorganic compounds selected from metal oxides, metal nitrides, metal carbides, metal oxycarbides, metal carbonitrides, and metal oxynitride carbides. It is preferable. Specific examples include inorganic compounds containing one or more elements selected from silicon, aluminum, magnesium, titanium, tin, indium, cerium, and zinc, and more specifically, silicon. Inorganic oxides such as oxides, aluminum oxides, magnesium oxides, titanium oxides, tin oxides, silicon zinc alloy oxides and indium alloy oxides, inorganics such as silicon nitrides, aluminum nitrides and titanium nitrides Inorganic silicon oxynitride such as nitride and silicon oxynitride can be given. More preferably, from the viewpoint of hydrophilicity, the inorganic layer 3 is a layer made of one or more selected from silicon oxide, silicon nitride, silicon oxynitride, and silicon oxide zinc, and among these, the inorganic layer 3 Is particularly preferably a layer made of silicon oxide. The inorganic layer 3 may use the said material independently, and may mix and use the said material in arbitrary ratios within the range of the summary of this invention.

  The contact angle of the inorganic layer 3 with respect to water is 40 ° or less. Since the inorganic layer 3 has excellent hydrophilicity, the transparent film 10 can exhibit good antifouling properties. The contact angle with respect to water is, for example, using a contact angle measuring device (manufactured by Kyowa Interface Chemical Co., Ltd., model number: CA-Z), dropping a certain amount of pure water on the surface of the inorganic layer 3, and after 10 seconds, an optical microscope. Alternatively, it can be measured by observing the shape of the water droplet with a CCD camera or the like.

  The present invention can achieve high hydrophilicity by reducing the amount of carbon element contained in the inorganic layer 3, and as a result, the antifouling property of the transparent film 10 can be improved. Specifically, the elemental amount of carbon contained in the inorganic layer 3 is preferably 20 mol% or less. Such an inorganic layer 3 can be produced by generating high-energy plasma by vacuum deposition in the presence of oxygen. More specifically, the monomer component of the raw material gas is further decomposed by generating high energy plasma in the presence of oxygen. Therefore, while the metal element contained in the monomer component is combined with oxygen to form the inorganic layer 3, the carbon atom contained in the monomer component is discharged as carbon dioxide, so the amount of carbon element is relative Therefore, the inorganic layer 3 becomes low.

  Although the thickness of the inorganic layer 3 varies depending on the inorganic compound to be used, it is usually 5 nm or more, preferably 10 nm or more. From the viewpoint of suppressing the occurrence of cracks and the like, it is usually 5000 nm or less, preferably 500 nm or less. Preferably it is 300 nm or less. Further, the inorganic layer 3 may be a single layer or two or more inorganic layers 3 having a total thickness within the above range. In the case of two or more inorganic layers 3, the same materials may be combined or different materials may be combined.

[Production method]
The manufacturing method of the transparent film 10 which concerns on this invention is the process (application | coating process) of apply | coating the resin composition containing urethane acrylate on the plastic base material 1, and the process of hardening the resin composition and forming the organic layer 2 (Organic layer forming step) and a step of forming the inorganic layer 3 on the organic layer 2 (inorganic layer forming step). The organic layer 2 has an immersion weight reduction rate of 6% or less, and arithmetic. The arithmetic average roughness of the surface after plasma irradiation with oxygen gas at a power of 300 W / sccm for 15 minutes on the surface having an average roughness (Ra) of 15 nm or less is the arithmetic average roughness before the plasma irradiation. The inorganic layer 3 is characterized in that the contact angle with respect to water is 40 ° or less.

  According to such a method for producing the transparent film 10, the organic layer 2 exhibits high weather resistance and plasma resistance. Therefore, even when the inorganic layer 3 is formed on the organic layer 2 with high energy, the organic layer 2 And the inorganic layer 3 can be prevented from delamination. Moreover, the inorganic layer 3 shows high hydrophilicity. As a result, the transparent film 10 which shows favorable antifouling property and a weather resistance can be manufactured. Hereinafter, each step will be described.

(Coating process)
The application step is a step of applying a resin composition containing urethane acrylate onto the plastic substrate 1. Since the plastic substrate 1 is as described in the explanation section of the “plastic substrate”, the description thereof is omitted here. In addition, the “resin composition” is cured to form the organic layer 2. For this reason, the resin composition includes the same components as the organic layer 2 described in the description section of the above “organic layer”, and the description thereof is omitted here.

  Examples of the method for applying the resin composition onto the plastic substrate 1 include a roll coating method, a gravure roll coating method, a kiss roll coating method, a reverse roll coating method, a Miya bar coating method, a gravure coating method, a spin coating method, And a die coating method. Further, such application may be performed directly on the plastic substrate 1, or after the resin composition is applied to the easily peeled substrate by the method described above, the plastic substrate is applied to the applied resin composition. 1 may be applied and the resin composition may be applied onto the plastic substrate 1.

  When the organic layer 2 has a concavo-convex shape, for example, a reverse shape of a desired concavo-convex shape is formed on the surface of the mold, the resin composition is poured into the mold, and the plastic substrate 1 is placed on the resin composition. By placing, the resin composition can be applied to the plastic substrate 1. In addition, as a method of forming a reverse shape of a desired concavo-convex shape on the surface of the mold, a conventionally known method can be applied, and for example, a method such as blasting or pressing can be applied.

  You may make a resin composition contain a solvent from the viewpoint of the viscosity adjustment at the time of manufacture. Solvents include alcohols such as isopropyl alcohol, methanol and ethanol; ketones such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; esters such as ethyl acetate and butyl acetate; halogenated hydrocarbons; aromatic carbonization such as toluene and xylene Mention may be made of hydrogen; or mixtures thereof. These solvents may be mixed and used at an arbitrary ratio within the scope of the gist of the present invention.

  After applying the resin composition, drying is performed as necessary. The drying temperature may be room temperature, but when the resin composition contains a solvent, it is preferable to perform drying to remove the solvent.

(Organic layer formation process)
The organic layer forming step is a step of forming the organic layer 2 by curing the resin composition applied on the plastic substrate 1. The organic layer 2 is preferably formed by curing so that the dip weight reduction rate is 6% or less. Since such an organic layer has a high degree of curing, it can exhibit high plasma resistance. Therefore, even when the inorganic layer 3 is formed by high-energy plasma in the presence of oxygen, it is possible to prevent the organic layer 2 and the inorganic layer 3 from being delaminated after the weather resistance test. As a result, the transparent film 10 which shows favorable weather resistance and antifouling property can be manufactured.

  Examples of the method of curing the resin composition include a method of curing by irradiating ionizing radiation such as ultraviolet rays and electron beams, a method of curing by heating, and the like. Among these, from the viewpoint of increasing the degree of curing of the organic layer 2, a method of curing by electron beam irradiation, a method of curing by heating after irradiation with ultraviolet rays, and the like are preferable. Among these, from the viewpoint of forming the organic layer 2 having a high degree of curing, a method of curing by electron beam irradiation can be preferably exemplified. Moreover, you may form the organic layer 2 combining these hardening methods.

  As an electron beam source, various electron beam accelerators such as a cockcroft Walton type, a bandegraft type, a resonant transformer type, an insulating core transformer type, a linear type, a dynamitron type, and a high frequency type can be used. The acceleration voltage of the electron beam is, for example, 70 kV or more and 1000 kV or less, and preferably 90 kV or more and 200 kV or less. The irradiation amount of the electron beam is, for example, 1 Mrad or more and 30 Mrad or less, and preferably 2.5 Mrad or more and 25 Mrad or less.

  As the ultraviolet light source, for example, a light source such as an ultra-high pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc lamp, a black light fluorescent lamp, a metal halide lamp is used. As the wavelength of the ultraviolet light, a wavelength range of 190 nm or more and 380 nm or less can be used. What is necessary is just to adjust suitably the time which irradiates an ultraviolet-ray from the viewpoint which carries out reliable hardening of an organic layer, considering industrial productivity. Moreover, hardening by heating is normally performed by maintaining at a temperature range of 160 ° C. or higher and 240 ° C. or lower for 2 hours or longer.

  The curing conditions for the organic layer 2 can be determined by actually measuring the immersion weight reduction rate of the organic layer 2. For example, the organic layer 2 may be measured by measuring the weight reduction rate by applying the resin composition to a release film (for example, Mitsui Chemicals Tosero Co., Ltd., trade name: Opulan) that has been easily peeled on one side. Can be measured by forming a cured product under the same curing conditions as those actually performed in the production, and then removing the cured product from the release film to produce a cured product of only the organic layer 2. As a measuring method, for example, a cured product of only the organic layer 2 is cut into an appropriate size, immersed in methyl ethyl ketone at room temperature for 24 hours, and calculated from a change in weight before and after the immersion of the cured product of only the organic layer 2.

(Inorganic layer forming process)
The inorganic layer forming step is a step of depositing an inorganic layer material (inorganic layer forming material) on the organic layer 2 to form the inorganic layer 3. Since the inorganic layer material is as described in the explanation section of the “inorganic layer”, the description thereof is omitted here.

Examples of the method for forming the inorganic layer 3 include a physical vapor deposition method such as a vacuum deposition method, a sputtering method, and an ion plating method, or a plasma chemical vapor deposition method. Among these, from the viewpoint of reducing the amount of carbon element contained in the inorganic layer 3 and enhancing hydrophilicity, an ion plating method and a plasma chemical vapor deposition method can be preferably exemplified. The film forming conditions for forming the inorganic layer 3 are not particularly limited as long as the amount of carbon element contained in the inorganic layer 3 can be reduced. For example, it is preferable to form the film by generating high energy plasma in the presence of oxygen. . For example, in the case of plasma chemical vapor deposition, it is preferable to apply power in a vacuum of 100 mTorr or less so that the output per unit monomer of the source gas is 20 W / sccm or more under oxygen gas, that is, 100 mTorr. In the following vacuum, it is preferable to apply power so that the power applied per 1 sccm of the flow rate of the raw material gas introduced into the film forming chamber is 20 W or more. Further, for example, in the case of an ion plating method, it is preferable to set the film formation power to 9 kW or more in a vacuum with a film formation pressure of 1.2 × 10 ⁻² Pa or less. Note that sccm is an abbreviation for standard cubic centimeter per minute.

  In addition, when the transparent film 10 has the other functional layer mentioned above, the formation process of those layers is included arbitrarily.

  EXAMPLES The present invention will be described more specifically with reference to examples. However, the present invention is not limited to the description of the following examples unless it exceeds the gist.

[Example 1]
The resin composition prepared in the following composition was coated on a release film (Mitsui Chemicals Tosero Co., Ltd., trade name: Opulan) with an applicator, and then an adhesive layer was formed on one side as a plastic substrate. A biaxially stretched polyethylene terephthalate film (made by Toyobo Co., Ltd., trade name: A4300) was bonded to the coated resin composition, and an electron beam with a voltage of 185 kV and a dose of 10 Mrad was irradiated through the plastic substrate. After the resin composition was cured, the above-described release film was peeled off to form an organic layer having a thickness of 60 μm.

(Composition of resin composition)
Urethane acrylate (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name: UV7000-B, Tg: 52 ° C., number of acryloyl groups per molecule: 2-3, molecular weight: 3500, cure shrinkage: 4% to 5%): 25 parts by mass-Release agent (3-methyl-2-phospholene-1-oxide): 2 parts by mass-Hydroxyphenyltriazine-based ultraviolet absorber (manufactured by BASF Japan, trade name: Tinuvin 479): 2 parts by mass Diluting solvent (toluene: methyl ethyl ketone = 1: 1 mixed solvent, manufactured by DNP Fine Chemical Co., Ltd., trade name: KT-11): 75 parts by mass

  The inorganic layer was formed by a plasma chemical vapor deposition method. Specifically, it is set in a plasma chemical vapor deposition apparatus in a direction to form the organic layer side of the plastic substrate on which the organic layer is formed, and hexamethyldisiloxane (manufactured by Shin-Etsu Chemical Co., Ltd.) as a raw material gas, Oxygen gas and argon gas were prepared. Each gas is supplied so that hexamethyldisiloxane: oxygen gas: argon gas = 1: 50: 3, and power is applied so that the output per unit monomer of the source gas is 20 W / sccm in a vacuum of 100 mTorr or less. Then, a silicon oxide layer having a thickness of 80 nm was formed. In addition, as a result of measuring the composition ratio of the inorganic layer of Example 1 by X-ray photoelectron spectroscopy using an X-ray photoelectron spectrometer (manufactured by KRATOS, model number: ESCA-3400), Si: O: C = 26: 55:19 (unit: mol%). Further, sccm is an abbreviation for standard cubic centimeter per minute, and the same applies to the following examples and comparative examples.

[Example 2]
The type of urethane acrylate to be blended in the resin composition is urethane acrylate (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name: UV-7510B, Tg: 17 ° C., molecular weight: 3500, number of acryloyl groups per molecule: 3, molecular weight: The transparent film of Example 2 was obtained in the same manner as in Example 1 except that it was changed to 3500, cure shrinkage: 4% to 5%. In addition, as a result of measuring the composition ratio of the inorganic layer in the same manner as in Example 1, it was Si: O: C = 26: 55: 19 (unit: mol%).

[Example 3]
A transparent film of Example 3 was obtained in the same manner as in Example 2 except that silicon oxide (SiO ₂ ) was used as an evaporation material and was formed by an ion plating method. The ion plating method was performed using Ar gas as a process gas, a film forming pressure of 1.2 × 10 ⁻² Pa, and a film forming power of 9 kW. In addition, as a result of measuring the composition ratio of the inorganic layer in the same manner as in Example 1, it was Si: O: C = 29: 57: 14 (unit: mol%).

[Example 4]
Further, 5 parts by mass of oligo [2-hydroxy-2-methyl- [1- (methylvinyl) phenyl] propanone] (photopolymerization initiator, manufactured by Lamberti, trade name: ESACUREONE) was added to the resin composition, Example 4 was applied in the same manner as in Example 2 except that the resin composition was coated on the material, then irradiated with ultraviolet rays of 300 mJ / cm ² and further heated at 120 ° C. for 1 hour to form a 60 μm thick organic layer. A transparent film was obtained. In addition, as a result of measuring the composition ratio of the inorganic layer in the same manner as in Example 1, it was Si: O: C = 29: 64: 7 (unit: mol%).

[Example 5]
Except for changing the diluent solvent (toluene: methyl ethyl ketone = 1: 1 mixed solvent, manufactured by DNP Fine Chemical Co., Ltd., trade name: KT-11) to 150 parts by mass, the same procedure as in Example 1 was performed. A transparent film of Example 5 was obtained.

[Example 6]
Except for changing the diluent solvent (toluene: methyl ethyl ketone = 1: 1 mixed solvent, manufactured by DNP Fine Chemical Co., Ltd., trade name: KT-11) to 40 parts by mass, the same procedure as in Example 1 was performed. A transparent film of Example 6 was obtained.

[Comparative Example 1]
A transparent film of Comparative Example 1 was obtained in the same manner as Example 2 except that the organic layer was cured by electron beam irradiation at a voltage of 185 kV and a dose of 5 Mrad. In addition, as a result of measuring the composition ratio of the inorganic layer in the same manner as in Example 1, it was Si: O: C = 26: 55: 19 (unit: mol%).

[Comparative Example 2]
The type of urethane acrylate compounded in the resin composition is urethane acrylate (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name: UV-7600B, Tg: 200 ° C. or higher, number of acryloyl groups per molecule: 6, molecular weight: 1400, curing A transparent film of Comparative Example 2 was obtained in the same manner as in Example 1 except that the shrinkage rate was changed to 6.3%. In addition, as a result of measuring the composition ratio of an inorganic layer like Example 1, it was Si: O: C = 30: 64: 6 (a unit is mol%).

[Comparative Example 3]
The type of urethane acrylate blended in the resin composition is urethane acrylate (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name: UV-7630B, Tg: 200 ° C. or higher, number of acryloyl groups per molecule: 6, molecular weight: 2200, curing A transparent film of Comparative Example 3 was obtained in the same manner as in Example 1 except that the shrinkage rate was changed to 6.4%. In addition, as a result of measuring the composition ratio of the inorganic layer in the same manner as in Example 1, it was Si: O: C = 26: 55: 19 (unit: mol%).

[Comparative Example 4]
The urethane acrylate compounded in the resin composition was changed to urethane acrylate (manufactured by Daicel Cytec Co., Ltd., trade name: EBECRYL285, Tg: 101.7 ° C., number of acryloyl groups per molecule: 3, molecular weight: 2300). The transparent film of Comparative Example 4 was obtained in the same manner as Example 1. In addition, as a result of measuring the composition ratio of the inorganic layer in the same manner as in Example 1, it was Si: O: C = 30: 59: 11 (unit: mol%).

[Comparative Example 5]
A transparent film of Comparative Example 5 was obtained in the same manner as in Example 1 except that when forming the inorganic layer, power was applied so that the power per monomer was 5 W / sccm. In addition, as a result of measuring the composition ratio of the inorganic layer in the same manner as in Example 1, it was Si: O: C = 32: 27: 41 (unit: mol%).

[Evaluation and results]
About the organic layer of Examples 1-6 and Comparative Examples 1-5, (a) The immersion weight reduction | decrease rate of the organic layer was measured. Moreover, about the transparent film of Examples 1-6 and Comparative Examples 1-5, (i) Measurement of the arithmetic mean roughness (Ra) of the surface before and behind the plasma treatment of an organic layer, (c) Contact angle of an inorganic layer After the measurement and (d) weather resistance test, the presence or absence of peeling between the organic layer and the inorganic layer was confirmed.

  Measurement of the immersion weight reduction rate of the organic layer is carried out by using a cured product of a resin composition cured under desired conditions on a release film (manufactured by Mitsui Chemical Tosero Co., Ltd., trade name: Opulan) on a 20 mm × 50 mm test piece. It cut out and peeled from the peeling film, and was immersed in MEK for 24 hours. Next, the test piece taken out from the MEK was dried at 60 ° C. for 24 hours, and the immersion weight reduction rate was calculated from the change in weight before and after the immersion.

  The arithmetic average roughness (Ra) of the organic layer is measured by removing the inorganic layer from the transparent film, and then exposing the surface of the exposed organic layer to a scanning probe microscope (product of SII Nanotechnology Inc., product name: Nano Measured by a method according to JIS B0601 (2001). In addition, the removal of the inorganic layer from the transparent film was performed by immersing in a 10 mass% concentration hydrofluoric acid for 5 minutes at room temperature to completely dissolve the inorganic layer.

The plasma treatment to the organic layer uses a plasma irradiation apparatus (manufactured by Yamato Scientific Co., Ltd., model number: PDC200), and oxygen ions are used as a reactive gas for the organic layer, and the reactive ions are output at 300 W / sccm for 15 minutes Etching was performed.

  The contact angle of the inorganic layer was measured by a dropping method with respect to water. Specifically, using a contact angle measuring device (manufactured by Kyowa Interface Chemical Co., Ltd., model number: CA-Z), one drop of pure water is dropped on the surface of the inorganic layer, and after 10 seconds, the shape of the water drop is measured with an optical microscope. Observed and measured contact angle.

  The weather resistance test for ultraviolet (UV) irradiation was carried out using a super accelerated weather resistance tester (manufactured by Iwasaki Electric Co., Ltd., trade name: Eye Super UV Tester, model number: SUV-W23). , (B), (C) was set to 1 cycle, and this was repeated 15 cycles, and a weather resistance test for 360 hours was performed.

(A) Irradiation with ultraviolet rays having an illuminance of 65 mW / cm ² and a peak wavelength of 365 nm in an atmosphere of temperature: 63 ° C. and humidity: 50% RH for 20 hours.
(B) Watering treatment (shower) is performed for 30 seconds.
(C) Hold for 4 hours in an atmosphere of temperature: 63 ° C. and humidity: 98% RH (no UV irradiation).

  In the weather resistance test for xenon (Xe) lamp light, the following (A) and (B) are set to one cycle on a transparent film using a xenon lamp irradiation device (product name: Weatherometer Ci4000, manufactured by Atlas Co., Ltd.) By repeating this for 148 cycles, a 360-hour weather resistance test was conducted.

(A) Xenon light with an illuminance of 60 mW / cm ² and a wavelength of 300 nm to 400 nm is irradiated for 128 minutes in an atmosphere of temperature: 65 ° C. and humidity: 50% RH.
(B) Sprinkling treatment (shower) is performed for 18 minutes.

  The presence or absence of peeling between the organic layer and the inorganic layer was confirmed by visually observing the transparent film after the above light resistance test.

  The results are shown in Table 1. The term “after the UV weathering test” means that the weathering test for ultraviolet irradiation has been performed for 360 hours, and the term “after the weathering test for Xe” means that the weathering test for xenon lamp light has been performed for 360 hours. .

  From the results in Table 1, the transparent films of Examples 1 to 6 exhibited good weather resistance because delamination between the organic layer and the inorganic layer did not occur even after the weather resistance test. Moreover, since the contact angle with respect to the water of an inorganic layer was 40 degrees or less, favorable antifouling property was shown.

  According to the present invention, since a transparent film exhibiting good weather resistance can be produced, this transparent film is mainly used in applications where high transparency and weather resistance are required, especially in the environment where it is exposed to ultraviolet rays for a long time such as outdoors. Applicable to the uses used below. Examples of such applications include concentrating sheets for solar cells, backsheets for solar cells, antireflection sheets for liquid crystal displays, films for electronic paper, electromagnetic wave shielding films for plasma displays, and organic electroluminescence. It is preferably used as a film used in an electronic device such as a film. In addition, overlay films for the purpose of surface protection of marking films used on the surfaces of railway vehicles, automobiles, vending machines, etc., surface protection films for exterior signage, outdoor windows in buildings, automobile windows, etc. As a transparent film that can be used outdoors for a long time, such as film for window pasting for lighting, light guide, heat ray reflection, and heat ray control, member for window for housing, film for agricultural greenhouse, etc. Preferably used.

DESCRIPTION OF SYMBOLS 1 Plastic base material 2 Organic layer 3 Inorganic layer 4,5 Uneven shape 6 Functional part 10,10A, 10B, 10C, 10D Transparent film S1 One side of plastic base material S2 Other side of plastic base material

Claims (6)

A plastic substrate, an organic layer provided on the plastic substrate, and an inorganic layer provided on the organic layer,
The organic layer is a cured product of the resin composition comprising a urethane acrylate, weight loss after immersing the organic layer in 24 hours methyl ethyl ketone at 6% or less, and, in JIS B0601 (2001) The surface of the surface having an arithmetic mean roughness (Ra) of 15 nm or less measured by a method similar to that described above after performing plasma irradiation with oxygen gas at an output of 300 W / sccm for 15 minutes is the surface Ra before the plasma irradiation. Less than 12 times Ra ,
The inorganic layer has a contact angle with water of 40 ° or less.   The transparent film according to claim 1, wherein the organic layer contains a weathering agent.   The said inorganic layer is 1 type, or 2 or more types of inorganic compounds chosen from a metal oxide, a metal nitride, a metal carbide, a metal oxycarbide, a metal carbonitride, and a metal oxynitride carbide. The transparent film as described in 2.   The transparent film according to any one of claims 1 to 3, wherein the resin composition is an electron beam curable resin composition. It includes a step of applying a resin composition comprising a urethane acrylate on the plastic substrate, forming an organic layer by curing the resin composition, and forming an inorganic layer on the organic layer ,
The organic layer has a weight loss rate of 6% or less after the organic layer is immersed in methyl ethyl ketone for 24 hours, and has an arithmetic average roughness (Ra) measured by a method according to JIS B0601 (2001). Ra of the surface after performing plasma irradiation with oxygen gas at a power of 300 W / sccm for 15 minutes on a surface of 15 nm or less is 12 times or less of Ra before the plasma irradiation,
The said inorganic layer is a manufacturing method of the transparent film characterized by the contact angle with respect to water being 40 degrees or less. The method for producing a transparent film according to claim 5, wherein the inorganic layer is formed by a plasma chemical vapor deposition method or an ion plating method.

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