Hard coat film

Abstract

To provide a hard coat film using a poor adhesion film as a base material, allowing the functions of water repellency, anti-fouling and low-friction, etc. by a hard coat without pretreatment to the base material and excellent even in hard coat adhesion and hardness.SOLUTION: A hard coat layer including at least an acrylate ultraviolet curable resin in which a relation between a functional group number C and a weight average molecular weight D satisfies the relational expressions 2:C-7.1×logD+13.6<0 and 0≤C-5.4×logD+12.8 and a surface modifier is laminated on at least one surface of a base film in which a relation between a water contact angle A (°) and arithmetic average surface roughness B (nm) on the surface of the base film satisfies the relational expression 1:0≤A-7.5×lnB-48. An absorption peak in infrared spectrophotometer measurement on the surface of the hard coat layer is at 1730 cm-1; and a water contact angle on the surface of the hard coat layer is 90° or more.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a hard coat film used for optical members and the like. [Background technology]

[0002] For example, the display surfaces of displays such as organic electroluminescence (EL) display devices and liquid crystal display devices (LCD) are required to be scratch-resistant so as to prevent scratches during handling and thus reduce visibility. Therefore, scratch resistance is generally imparted to the display surfaces of displays by using a hard coat film in which a hard coat layer is provided on a substrate film.

[0003] In recent years, there has been a need to smooth the surface roughness of resin films used in products such as film-type solar cells, insulating layers for motors, and vibration plates, in addition to conventional display applications. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2023-65333 Summary of the Invention [Problem to be solved by the invention]

[0005] As mentioned above, in recent years, smoothness has become a particular requirement for products, and therefore the use of smooth films with low surface roughness is also required for film substrates. However, depending on the film substrate, if the surface is smooth due to poor wettability, a problem occurs in that the hard coat layer is difficult to adhere to. When such a film with a smooth surface but poor wettability is used, not only is the adhesion of the hard coat difficult to achieve, but there is also the problem that it is difficult to provide functions such as antifouling and low friction. As a conventional technique, for example, Patent Document 1 mentioned above discloses a technique for improving the wettability of a film surface by plasma treatment. However, if the wettability of the film surface is improved by plasma treatment or the like and then a hard coat treatment is performed to make the film functional, the number of manufacturing steps increases, leading to increased costs.

[0006] Therefore, an object of the present invention is to provide a hard-coated film that uses a poorly adhesive film as a substrate, and enables the hard-coat to provide functions such as water repellency, antifouling, and low friction without pre-treatment of the substrate, and that also has excellent hard-coat adhesion and hardness. [Means for solving the problem]

[0007] As a result of extensive research into solving the above problems, the present inventors have found that the above problems can be solved by the invention having the following configuration. That is, the present invention has the following configuration.

[0008] (First invention) The relationship between the water contact angle A (°) and the arithmetic mean surface roughness B (nm) of the substrate film surface satisfies the relational expression 1: 0≦A−7.5×lnB−48. A hard coat layer containing at least an acrylate-based ultraviolet curable resin and a surface modifier is laminated on at least one side of the substrate film, and the relationship between the number of functional groups C and the weight average molecular weight D satisfies the relational expression 2: C−7.1×logD+13.6<0 and 0≦C−5.4×logD+12.8. The surface of the hard coat layer has a wavelength of 1730 cm when measured with an infrared spectrophotometer. -1 and the water contact angle of the surface of the hard coat layer is 90° or more.

[0009] (Second Invention) The hard coat film according to the first aspect of the present invention, wherein the surface modifier is at least one selected from the group consisting of a silicone-containing polymer and a fluorine-containing polymer. (Third Invention) The hard coat film according to the first or second invention, characterized in that the amount of the surface modifier is 0.2 to 0.6 parts by mass per 100 parts by mass of the acrylate ultraviolet curable resin of the hard coat layer.

[0010] (Fourth Invention) The hard coat layer further contains silica fine particles, and the surface of the hard coat layer is measured with an infrared spectrophotometer at 1050 cm -1 The hard coat film according to the first or second invention, characterized in that it has an absorption peak at (Fifth Invention) The hard coat film according to the first or second invention, wherein the static friction coefficient of the surface of the hard coat layer against a SUS material is 0.4 or less.

[0011] (Sixth Invention) The hard coat film according to the first or second invention, wherein the remaining rate of the hard coat layer of the hard coat film measured by the cross-cut method of JIS-K5600-5-6 is 75% or more. (Seventh Invention) The hard coat film according to the first or second invention, wherein the pencil hardness of the surface of the hard coat film is 2B or more.

[0012] (8th invention) The hard coat film according to the first or second invention, wherein the hard coat layer has a thickness of 3 μm or less. (9th invention) The hard coat film according to the first or second invention, wherein the substrate film is a polyaryl ether ketone film or a polyimide film. [Effects of the Invention]

[0013] According to the present invention, even if a poorly adherent film is used as the substrate, it is possible to provide a hard coat film that can be functionalized with water repellency, antifouling, low friction, etc., without pre-treatment of the substrate, and further, that has excellent hard coat adhesion and hardness. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, embodiments for carrying out the present invention will be described in detail, but the present invention is not limited to the following embodiments. In this specification, unless otherwise specified, the expression "xx to yy" as a range of numerical values ​​means "xx or more and yy or less."

[0015] As described in the first aspect of the present invention, the hard coat film of the present invention has a substrate film surface having a water contact angle A (°) and an arithmetic mean surface roughness B (nm) that satisfies the relational expression 1: 0≦A−7.5×lnB−48, and a hard coat layer containing at least an acrylate-based ultraviolet-curable resin and a surface modifier, the relational expression 2: C−7.1×logD+13.6<0 and 0≦C−5.4×logD+12.8, laminated on at least one side of the substrate film. The hard coat layer has a water contact angle A (°) and an arithmetic mean surface roughness B (nm) that satisfies the relational expression 1: 0≦A−7.5×lnB−48, the number of functional groups C and the weight average molecular weight D that satisfies the relational expression 2: C−7.1×logD+13.6<0 and 0≦C−5.4×logD+12.8, and the surface of the hard coat layer has a wavelength of 1730 cm when measured with an infrared spectrophotometer. -1 and the hard coat layer surface has a water contact angle of 90° or more. The structure of the hard coat film of the present invention will be described in detail below.

[0016] [Base film] First, the substrate film of the hard coat film will be described. The substrate to be coated for the hard coat film of the present invention is a substrate film whose surface water contact angle A (°) and arithmetic mean surface roughness B (nm) satisfy the following relationship: 1:0≦A-7.5×lnB-48. In this specification, "lnB" represents the natural logarithm of B, with e (Napier's constant) as the base. The arithmetic mean surface roughness is defined in ISO 25178 as the average absolute value of the height difference between each point on a surface and the mean plane on a certain reference plane. In other words, it is the average value of the irregularities when the heights of each point below the mean plane are folded back to the positive side. Specifically, it can be calculated from the data of the film surface roughness curve measured using a white light interference microscope.

[0017] A substrate film that satisfies the above relational expression 1 is a low-adhesion film that is smooth but has poor wettability. In recent years, smoothness has been required for products such as film-type solar cells, insulating layers for motors, and vibration plates, and there is also a need to smooth the surface roughness of the hard coat films used in these products. Therefore, it is necessary to use such low-adhesion films. However, when such low-adhesion films with smooth surfaces but poor wettability are used, there is a problem that the adhesion of the hard coat is poor, making it difficult to achieve functions such as anti-fouling and low friction. The present invention is suitable for use in cases where a poorly adherent film that satisfies the above-mentioned relational formula 1 is used as the substrate. According to the present invention, even when a poorly adherent film is used as the substrate, it is possible to provide a hard coat film that is functionalized with water repellency, antifouling properties, low friction, etc., by a hard coat without any pretreatment of the substrate, and furthermore, that is excellent in hard coat adhesion and hardness.

[0018] Preferred examples of the substrate film used in the present invention that satisfies the above-mentioned relational expression 1 include polyaryl ether ketone films and polyimide films. In addition to polyaryl ether ketone films and polyimide films, cycloolefin polymer films, polyethylene terephthalate films, etc. are also suitable. The substrate film used in the present invention is not limited to films made of these materials as long as it satisfies the above relational expression 1. The substrate film may be formed by any suitable film forming method, such as solution casting, melt extrusion, calendaring, compression molding, etc., but melt extrusion is particularly preferred. Because the melt extrusion method does not use a solvent, it can reduce production costs and the burden on the global environment and working environment caused by solvents.

[0019] In the present invention, the thickness of the substrate film is appropriately selected depending on the application, but from the viewpoint of the demand for thinner hard coat films in accordance with the thinning and weight reduction of the applied products, it is preferably 50 μm or less, particularly preferably 30 μm or less, while from the viewpoint of mechanical strength, handleability, etc., it is preferably 10 μm or more.

[0020] [Hard coat layer] Next, the hard coat layer of the hard coat film will be described. In the present invention, the hard coat layer contains at least an acrylate-based ultraviolet-curable resin and a surface modifier. In the present invention, it is preferable to use an ultraviolet-curable resin as the resin contained in the hard coat layer, since it can impart surface hardness (pencil hardness, scratch resistance) to the hard coat layer, and the degree of crosslinking can be adjusted by the amount of ultraviolet light exposure, making it possible to adjust the surface hardness of the hard coat layer.

[0021] The acrylate-based UV-curable resin used in the present invention is a transparent resin that cures upon exposure to ultraviolet (UV) light, and is an acrylate-based UV-curable resin in which the relationship between the number of functional groups C and the weight-average molecular weight D satisfies the following relational expression 2: C - 7.1 × logD + 13.6 < 0 and 0 ≦ C - 5.4 × logD + 12.8 (hereinafter sometimes referred to as the "acrylate-based UV-curable resin of the present invention"). In this specification, "logD" represents the common logarithm of D with the base 10.

[0022] To achieve the object of the present invention, when using the above-mentioned poorly adhesive substrate film, it is necessary to select a hard coat coating material that is highly flexible and exhibits little cure shrinkage. Therefore, the present invention is characterized by applying an acrylate-based UV-curable resin in which the relationship between the number of functional groups C and the weight-average molecular weight D satisfies the relational expression 2: C - 7.1 × log D + 13.6 < 0 and 0 ≦ C - 5.4 × log D + 12.8.

[0023] When the above-mentioned relationship is not satisfied, for example, when the relationship between the number of functional groups C and the weight-average molecular weight D is C-5.4×logD+12.8<0, the number of functional groups relative to the molecular weight is small, resulting in few crosslinking points, poor UV curability, and difficulty in achieving adhesion. Also, when the relationship between the number of functional groups C and the weight-average molecular weight D is 0≦C-7.1×logD+13.6, the number of functional groups relative to the molecular weight is large, resulting in many crosslinking points, which increases shrinkage due to curing, resulting in poor conformability to the substrate and difficulty in achieving adhesion. Therefore, in the present invention, by hard-coating the above-mentioned poorly adherent substrate film with a hard-coating paint containing an acrylate-based UV-curable resin that satisfies C-7.1×logD+13.6<0 and 0≦C-5.4×logD+12.8, a hard-coated film with excellent hard-coat adhesion can be obtained even without pretreatment of the substrate.

[0024] In the present invention, the acrylate-based ultraviolet-curable resin contained in the hard coat layer is not particularly limited as long as it is an acrylate-based ultraviolet-curable resin of the present invention in which the relationship between the number of functional groups C and the weight-average molecular weight D satisfies the above-mentioned relational formula 2. However, in order to ensure coating hardness and form a three-dimensional crosslinked structure in the hard coat layer, it is preferable to use an acrylate that is UV-curable and has three or more (meth)acryloyloxy groups as functional groups in one molecule. Specific examples of UV-curable polyfunctional acrylates having three or more (meth)acryloyloxy groups in the molecule include trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, trimethylolpropane ethoxy triacrylate, glycerin propoxy triacrylate, ditrimethylolpropane tetraacrylate, etc. The polyfunctional acrylates may be used alone or in combination of two or more.

[0025] Furthermore, the weight-average molecular weight of the acrylate-based UV-curable resin used in the hard coat layer is not particularly limited as long as the relationship between the number of functional groups C and the weight-average molecular weight D is within the range satisfying the above-mentioned relational expression 2. For example, it is preferable to use a monomer, oligomer, or polymer with a weight-average molecular weight in the range of 1000 to 4900, more preferably 1000 to 4000, and even more preferably 1000 to 3600. If the weight-average molecular weight is less than 1000, the curing shrinkage upon curing by UV irradiation is large, and the phenomenon of the hard coat film curling toward the hard coat layer side becomes significant, causing problems in subsequent processing steps and poor processability. On the other hand, if the weight-average molecular weight exceeds 4900, the flexibility of the hard coat layer is increased, but the hardness is insufficient, making it unsuitable. The weight average molecular weight in the present invention is an average molecular weight obtained by gel permeation chromatography (GPC) analysis in terms of standard polystyrene.

[0026] Furthermore, when the weight-average molecular weight of the acrylate-based ultraviolet-curable resin of the present invention used in the hard coat layer is less than 1500, the number of functional groups per molecule is desirably 4 to less than 9. Furthermore, when the weight-average molecular weight of the ultraviolet-curable resin is 1500 or more, the number of functional groups per molecule is desirably 4 to 17. Within the above ranges, curling can be suppressed and appropriate processability can be maintained.

[0027] In addition to the above-mentioned ultraviolet-curable resin, the resin contained in the hard coat layer may be a thermoplastic resin such as polyethylene, polypropylene, polystyrene, polycarbonate, polyester, acrylic, styrene-acrylic, or cellulose, or a thermosetting resin such as a phenolic resin, urea resin, unsaturated polyester, epoxy, or silicone resin, within a range that does not impair the hardness and scratch resistance of the hard coat layer.

[0028] In the present invention, the hard coat layer contains a surface modifier in addition to the ultraviolet-curable resin. The use of a surface modifier can impart functions such as water repellency, antifouling properties, and low-friction properties to the hard coat. For example, adding a water-repellent surface modifier to a hard coat coating can impart water repellency to the hard coat film, and adding an antifouling surface modifier to a hard coat coating can impart antifouling properties to the hard coat film. Furthermore, adding a low-friction surface modifier to a hard coat coating can impart low-friction properties to the hard coat film.

[0029] In the present invention, for example, a silicone-containing polymer or a fluorine-containing polymer can be preferably used as the surface modifier. By using a silicone-containing polymer or a fluorine-containing polymer in a hard coat paint, it is possible to impart desired functions such as water repellency, antifouling properties, and low friction performance to the hard coat film. In particular, from the viewpoint of low friction performance, a silicone-containing polymer can be more preferably used. The above surface modifiers may be used alone or in combination of two or more kinds.

[0030] The amount of the surface modifier is preferably in the range of 0.2 to 0.6 parts by mass relative to 100 parts by mass of the acrylate-based UV-curable resin of the hard coat layer. If the amount of surface modifier is less than 0.2 parts by mass, the hard coat's functions such as water repellency, antifouling, and low-friction performance will not be fully exhibited. On the other hand, if the amount of surface modifier is more than 0.6 parts by mass, the surface modifier will not be oriented on the surface of the hard coat, resulting in reduced adhesion, which is not suitable. The amount of the surface modifier to be added is particularly preferably within the range of 0.25 to 0.5 parts by mass relative to 100 parts by mass of the acrylate ultraviolet curable resin of the hard coat layer.

[0031] Furthermore, by incorporating inorganic oxide fine particles into the hard coat layer, it is possible to further improve the surface hardness (pencil hardness, scratch resistance). That is, by applying a hard coat coating material that is harder than the substrate film, a hard coat film with excellent hardness can be obtained. Furthermore, by incorporating inorganic oxide fine particles into the hard coat layer, curling due to cure shrinkage of the hard coat layer can be suppressed, and the adhesion of the hard coat can be improved.

[0032] In this case, the inorganic oxide fine particles preferably have an average particle size in the range of 5 to 50 nm, more preferably in the range of 10 to 40 nm. If the average particle size is less than 5 nm, it is difficult to obtain sufficient surface hardness. On the other hand, if the average particle size exceeds 50 nm, the gloss and transparency of the hard coat layer tend to decrease, and flexibility may also decrease.

[0033] In the present invention, examples of the inorganic oxide fine particles include silica and alumina, among which silica fine particles are particularly suitable. When the hard coat layer contains, for example, silica fine particles, the surface of the hard coat layer is measured with an infrared spectrophotometer at 1050 cm -1 Here, the absorption peak at 1050 cm measured by an infrared spectrophotometer -1 The absorption peak is due to the stretching vibration of Si-O.

[0034] In the present invention, the content of inorganic oxide fine particles is preferably 0.1 to 12.0 parts by mass relative to 100 parts by mass of the ultraviolet-curable resin in the hard coat layer. If the content of inorganic oxide fine particles is less than 0.1 part by mass, it is difficult to obtain an effect of improving surface hardness. On the other hand, if the content exceeds 12.0 parts by mass, haze increases, which is undesirable.

[0035] Furthermore, a leveling agent can be used in the hard coat layer to improve coating properties, and known leveling agents such as fluorine-based, acrylic, siloxane-based, and their adducts or mixtures can be used. The amount of the leveling agent added is not particularly limited, but is preferably, for example, 0.05% by mass to 2.0% by mass relative to the resin solid content in the coating material for the hard coat layer.

[0036] The hard coating material for forming the hard coating layer contains a photopolymerization initiator in addition to the acrylate-based ultraviolet-curable resin of the present invention. Examples of such photopolymerization initiators include commercially available acetophenones such as IRGACURE 651 and IRGACURE 184 (both trade names: manufactured by BASF) and benzophenones such as IRGACURE 500 (trade name: manufactured by BASF).

[0037] Other additives that may be added to the hard coat layer, if necessary, include an ultraviolet absorber, an antifoaming agent, a surface tension adjuster, an antioxidant, an antistatic agent, a light stabilizer, and the like, within the range that does not impair the effects of the present invention.

[0038] The hard coat layer is formed by applying a hard coat coating material containing the acrylate-based UV-curable resin of the present invention, the surface modifier, inorganic oxide particles, photopolymerization initiator, and other additives dissolved or dispersed in a suitable solvent to at least one side of the substrate film, drying the coating material, and then curing the coating material by irradiating with ultraviolet (UV) light. The solvent can be selected appropriately depending on the solubility of the resins and other components, as long as it can uniformly dissolve or disperse at least the solid components (resin, surface modifier, inorganic oxide particles, photopolymerization initiator, and other additives). Examples of suitable solvents include aromatic solvents such as toluene, xylene, and n-heptane; aliphatic solvents such as cyclohexane, methylcyclohexane, and ethylcyclohexane; ester solvents such as methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, and methyl lactate; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; and alcohol solvents such as methanol, ethanol, isopropyl alcohol, and n-propyl alcohol. These solvents can be used alone or in combination.

[0039] The method for applying the hard coating paint to form the hard coating layer is not particularly limited, but the hard coating paint can be applied by a known coating method such as gravure coating, microgravure coating, fountain bar coating, slide die coating, slot die coating, screen printing, or spray coating, and then dried at a temperature of usually about 50 to 120°C.

[0040] The amount of ultraviolet (UV) irradiation after forming the hard coat layer coating film may be any amount necessary to provide the hard coat layer with sufficient hardness, and can be appropriately set depending on the type of UV-curable resin, etc.

[0041] In the present invention, the film thickness (coating film thickness) of the hard coat layer is, for example, preferably less than 5 μm, and more preferably 3 μm or less. It is more preferably in the range of 1 μm to 3 μm, which improves the hard coat adhesion. If the film thickness is too thick, it is thought that the hard coat adhesion will deteriorate due to the influence of cure shrinkage. A hard coat layer thickness of less than 1 μm is not preferred because the required hardness is reduced, whereas a hard coat layer thickness of 5 μm or more is not preferred because it is prone to severe curling, reducing handleability during the manufacturing process and from the viewpoint of thinning the hard coat film.

[0042] As described above, the hard coat film of the present invention comprises a substrate film and a hard coat layer containing at least the acrylate-based ultraviolet-curable resin of the present invention and a surface modifier laminated on at least one surface of the substrate film.

[0043] The hard coat film of the present invention has a hard coat layer surface having a wavelength of 1730 cm as measured by an infrared spectrophotometer. -1 It has an absorption peak at Here, the 1730 cm -1That is, the hard coat film of the present invention contains the acrylate-based ultraviolet-curable resin of the present invention in the hard coat layer, and the absorption peak of C═O stretching vibration is due to the carbonyl group (skeleton) contained in the acrylate-based ultraviolet-curable resin of the present invention.

[0044] The hard coat film of the present invention is further characterized by having the following properties. The hard coat film of the present invention is characterized in that the water contact angle of the surface of the hard coat layer is 90° or more. That is, the hard coat film of the present invention has water repellency and antifouling properties due to the hard coat.

[0045] The hard coat film of the present invention is characterized in that the static friction coefficient of the surface of the hard coat layer against a SUS material is 0.4 or less. That is, the hard coat film of the present invention has low friction properties due to the hard coat.

[0046] The hard coat film of the present invention is characterized in that the remaining rate of the hard coat layer of the hard coat film measured by the cross-cut method of JIS-K5600-5-6 is 75% or more. That is, the hard coat film of the present invention also has excellent hard coat adhesion.

[0047] The hard coat film of the present invention is characterized in that the pencil hardness of the surface of the hard coat film is 2B or more. That is, the hard coat film of the present invention is also excellent in hardness (surface hardness).

[0048] As explained in detail above, according to the present invention, even if a poorly adherent film is used as the substrate, it is possible to provide functionalities such as water repellency, antifouling, and low friction by the hard coat without pre-treating the substrate, and it is also possible to obtain a hard coat film that is excellent in hard coat adhesion and hardness. [Example]

[0049] Next, the embodiments of the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples. In the following description, "parts" means parts by mass unless otherwise specified, and "%" means % by mass unless otherwise specified.

[0050] Example 1 [Preparation of Coating Solution for Forming Hard Coat Layer] A coating solution for forming a hard coat layer (hereinafter also referred to as "hard coat paint") with a final solids concentration of 35% was prepared by blending 94 parts of an acrylate-based ultraviolet-curing resin paint (Art Resin UN-908 (trade name); manufactured by Negami Chemical Industries, Ltd.) as the base agent with 5 parts of Omnirad184 (photopolymerization initiator; manufactured by BASF) and 0.5 parts of a silicone-containing polymer (GL-02R; manufactured by Kyoeisha Chemical Co., Ltd.) as a surface modifier, and diluting the mixture with ethyl acetate / ethyl cellosolve = 70 / 30 (parts by weight). The number C of functional groups ((meth)acryloyloxy groups) of the acrylate-based ultraviolet-curable resin, the weight-average molecular weight D, and the values ​​of logD, C-7.1×logD+13.6, and C-5.4×logD+12.8 calculated from the values ​​of C and D are shown in Table 1 below. [Preparation of hard-coated film] The above hard coat paint was applied to one side of a 50 μm thick polyimide film (manufactured by DuPont-Toray Co., Ltd.) (abbreviated as "PI" in Table 1) using a bar coater, and then dried with hot air in a drying oven at 80°C for 1 minute to form a coating layer with a coating thickness of 3.0 μm. This was then exposed to UV irradiation at a dose of 300 mJ / cm using a UV irradiation device set at a height of 60 mm from the coated surface. 2 The hard coat film of Example 1 was prepared by curing the coated layer by irradiation with ultraviolet light. The water contact angle A (°) and the arithmetic mean surface roughness B (nm) of the polyimide film surface are shown in Table 1 below. The water contact angle was measured using the method described below. The arithmetic mean surface roughness was measured at 10x magnification using a scanning white light interference microscope (VS-1800, manufactured by Hitachi High-Technologies Corporation).

[0051] Example 2 A hard coat coating material prepared in the same manner as in Example 1 was used, except that 0.25 parts of a surface modifier (GL-02R; manufactured by Kyoeisha Chemical Co., Ltd.) was added, and a hard coat film of Example 2 was produced in the same manner as in Example 1.

[0052] Example 3 A hard coat coating material prepared in the same manner as in Example 1 was used, except that the surface modifier was changed to a fluorine-containing polymer (RS-75-A; manufactured by DIC Corporation) and 0.25 parts was added. A hard coat film of Example 3 was produced in the same manner as in Example 1.

[0053] Example 4 A hard coat coating material prepared in the same manner as in Example 1 was used, except that 10 parts of silica fine particles (ELCOM-V-8804; manufactured by JGC Catalysts and Chemicals Co., Ltd.) were added, and a hard coat film of Example 4 was produced in the same manner as in Example 1.

[0054] Example 5 The hard coat film of Example 5 was produced in the same manner as in Example 1, except that the substrate film was changed to a 200 μm thick polyether ether ketone film (manufactured by Polypla-Evonik Co., Ltd.) (abbreviated as "PEEK" in Table 1). A hard coat paint prepared in the same manner as in Example 1 was used.

[0055] Example 6 A hard coat film of Example 6 was produced in the same manner as in Example 1, except that the coating thickness of the coating layer was changed to 4.0 μm, using a hard coat paint prepared in the same manner as in Example 1.

[0056] Example 7 A hard coat film of Example 7 was produced in the same manner as in Example 1, except that the acrylate-based ultraviolet-curable resin paint was changed to Art Resin UN-904 (trade name) (manufactured by Negami Chemical Industrial Co., Ltd.). A hard coat paint prepared in the same manner as in Example 1 was used.

[0057] Example 8 A hard coat coating material prepared in the same manner as in Example 1 was used, except that the acrylate-based ultraviolet-curable resin coating material was changed to EBECRYL1290 (trade name) (manufactured by Daicel-Allnex Co., Ltd.), and the hard coat film of Example 8 was produced in the same manner as in Example 7.

[0058] (Comparative Example 1) A hard coat coating material prepared in the same manner as in Example 1 except that it did not contain a surface modifier (GL-02R; manufactured by Kyoeisha Chemical Co., Ltd.) was used, and a hard coat film of Comparative Example 1 was produced in the same manner as in Example 1.

[0059] (Comparative Example 2) A hard coat coating material prepared in the same manner as in Example 1 was used, except that 0.1 parts of a surface modifier (GL-02R; manufactured by Kyoeisha Chemical Co., Ltd.) was added, and a hard coat film of Comparative Example 2 was produced in the same manner as in Example 1.

[0060] (Comparative Example 3) A hard coat coating material prepared in the same manner as in Example 1 was used, except that the surface modifier was changed to a fluorine-containing polymer (RS-75-A; manufactured by DIC Corporation) and was blended in an amount of 0.1 parts. A hard coat film of Comparative Example 3 was produced in the same manner as in Example 1.

[0061] Comparative Example 4 A hard coat coating material prepared in the same manner as in Example 1 was used, except that one part of a surface modifier (GL-02R; manufactured by Kyoeisha Chemical Co., Ltd.) was added, and a hard coat film of Comparative Example 4 was produced in the same manner as in Example 1.

[0062] (Comparative Example 5) A hard coat film of Comparative Example 5 was produced in the same manner as in Example 1, except that the acrylate-based ultraviolet-curable resin coating was changed to NIPAM (trade name) (manufactured by KJ Chemicals Co., Ltd.).

[0063] (Comparative Example 6) A hard coat film of Comparative Example 6 was produced in the same manner as in Example 1, except that the acrylate-based ultraviolet-curing resin paint was changed to Art Resin UN-906AVN (trade name) (manufactured by Negami Chemical Industrial Co., Ltd.). A hard coat paint prepared in the same manner as in Example 1 was used.

[0064] (Comparative Example 7) A hard coat film of Comparative Example 7 was produced in the same manner as in Example 1, except that the acrylate-based ultraviolet-curable resin paint was changed to Art Resin M-3N (trade name) (manufactured by Negami Chemical Industrial Co., Ltd.). A hard coat paint prepared in the same manner as in Example 1 was used.

[0065] (Comparative Example 8) A hard coat film of Comparative Example 8 was produced in the same manner as in Example 1, except that the acrylate-based ultraviolet-curable resin paint was changed to KRM8528 (trade name) (manufactured by Daicel-Allnex Co., Ltd.). A hard coat paint prepared in the same manner as in Example 1 was used.

[0066] Comparative Example 9 A hard coat film of Comparative Example 9 was produced in the same manner as in Example 1, except that the acrylate-based ultraviolet-curable resin paint was changed to Art Resin UN954 (product name) (manufactured by Negami Chemical Industrial Co., Ltd.). A hard coat paint prepared in the same manner as in Example 1 was used.

[0067] (Comparative Example 10) A hard coat film of Comparative Example 10 was produced in the same manner as in Example 1, except that the acrylate-based ultraviolet-curing resin paint was changed to Shikou UV-7610B (trade name) (manufactured by Mitsubishi Chemical Corporation). A hard coat paint prepared in the same manner as in Example 1 was used.

[0068] (Comparative Example 11) A hard coat film of Comparative Example 11 was produced in the same manner as in Example 1, except that the acrylate-based ultraviolet-curable resin coating was changed to IRR742 (trade name) (manufactured by Daicel Allnex Co., Ltd.). A hard coat coating prepared in the same manner as in Example 1 was used.

[0069] <Evaluation> The hard coat films of the Examples and Comparative Examples prepared as described above were evaluated for the following items, and the results are summarized in Table 1 for the Examples and Table 2 for the Comparative Examples.

[0070] <Measurement of the hard coat layer surface using an infrared spectrophotometer> Measurement was performed using an infrared spectrophotometer (Spectrum 100, manufactured by PerkinElmer) using the ATR method. The 1730 cm -1 and the peak intensity at 1050 cm -1 The peak intensity was checked to confirm whether or not there was an absorption peak.

[0071] <Water contact angle measurement conditions> Using a fully automatic contact angle meter DM-701 manufactured by Kyowa Interface Science Co., Ltd., 2 μL of water (pure water) was dropped and the contact angle was measured after 1 second.

[0072] <Cross-cut method test conditions> The test was carried out in accordance with the cross-cut method described in JIS-K5600-5-6. A cross-cut peel test jig was used to test the hard coat layer surface with a 1 mm 2One hundred cross-cuts of the above were prepared, and adhesive tape No. 252 manufactured by Sekisui Chemical Co., Ltd. was attached thereon and pressed evenly using a spatula. The adhesive tape was then peeled off at an angle of 60 degrees, and the remaining rate of the hard coat layer (the ratio of the number of remaining cross-cuts) was measured.

[0073] <Static friction coefficient measurement conditions> The static friction coefficient of the hard coat layer surface was measured using an automatic friction and wear analyzer TSf-502 manufactured by Kyowa Interface Science Co., Ltd., under a load of 100 gf / cm 2 , the value measured against a metal plate (SUS material).

[0074] <Pencil hardness measurement conditions> The pencil hardness was measured according to the test method of JIS-K-5600-5-4, and the hardness at which no scratches were generated on the surface of the hard coat layer was recorded.

[0075] [Table 1]

[0076] [Table 2]

[0077] As is clear from the results in Table 1 above, the hard coat films of the examples of the present invention have a water contact angle A (°) of 1730 cm as measured by an infrared spectrophotometer for poorly adhesive substrate films in which the relationship between the water contact angle A (°) and the arithmetic mean surface roughness B (nm) of the substrate film surface satisfies the relational expression 1:0≦A-7.5×lnB-48. -1The hard coat film has an absorption peak of 1000 nm and is laminated with a hard coat layer containing at least an acrylate-based UV-curable resin and a surface modifier, and the relationship between the number of functional groups C and the weight-average molecular weight D satisfies the relationship 2: C - 7.1 × log D + 13.6 < 0 and 0 ≦ C - 5.4 × log D + 12.8. Even though a poorly adherent film is used as the substrate, the hard coat provides water repellency, stain resistance, low friction, and other properties, and also has excellent hard coat adhesion and hardness. Specifically, the hard coat layer surface has a contact angle of 90° or more, a hard coat layer survival rate of 75% or more as measured by the cross-cut method, a static friction coefficient of 0.4 or less, and a pencil hardness of 2B or more.

[0078] In addition, as in Example 4, silica fine particles were contained in the hard coat layer, and the IR spectrum at 1050 cm was measured by an infrared spectrophotometer. -1 By having an absorption peak of 1000 nm, the surface hardness is improved and the hard coat adhesion is improved by suppressing the cure shrinkage of the hard coat layer. Furthermore, a comparison between Example 1 and Example 6 shows that adhesion is improved when the hard coat layer has a film thickness of, for example, 3 μm. It is thought that if the film thickness is thicker than 3 μm, adhesion will decrease due to the influence of cure shrinkage.

[0079] Furthermore, a comparison of Examples 1, 2, and 5 to 8 reveals that the use of a silicone-containing polymer surface modifier results in a lower static friction coefficient than that of a fluorine-containing polymer. Therefore, it is preferable to use at least one type of surface modifier selected from silicone-containing polymers and fluorine-containing polymers, with silicone-containing polymers being particularly preferable from the perspective of low friction performance. The amount of surface modifier added is preferably 0.25 to 0.5 parts by mass, as in the examples of the present invention, because a water contact angle of less than 90° is achieved at 0.1% (Comparative Example 2) and the hard coat layer survival rate is significantly reduced at 1% (Comparative Example 4).

[0080] On the other hand, the results in Table 2 reveal the following: Comparative Example 1, which does not use a surface modifier, does not provide sufficient water repellency. Comparative Examples 2 and 3, which use a small amount of surface modifier (0.1%), provide a water contact angle of less than 90°, failing to provide sufficient water repellency. Comparative Example 4, which uses a large amount of surface modifier (1%), reduces hard coat adhesion and significantly reduces the hard coat layer survival rate.

[0081] Furthermore, in Comparative Examples 5 and 6, which use an acrylate-based ultraviolet-curable resin in which the relationship between the number of functional groups C and the weight-average molecular weight D does not satisfy C-7.1×logD+13.6<0, good hard coat adhesion is not obtained. When the relationship between the number of functional groups C and the weight-average molecular weight D is 0≦C-7.1×logD+13.6, the number of functional groups is high relative to the molecular weight, resulting in many crosslinking points and significant shrinkage due to curing, which leads to poor conformability to the substrate and makes it difficult to obtain good adhesion.

[0082] Furthermore, in Comparative Examples 7 to 11, which use an acrylate-based UV-curable resin in which the relationship between the number of functional groups C and the weight-average molecular weight D does not satisfy 0≦C−5.4×logD+12.8, good hard coat adhesion is not obtained. When the relationship between the number of functional groups C and the weight-average molecular weight D is C−5.4×logD+12.8<0, the number of functional groups is small relative to the molecular weight, resulting in few crosslinking points, poor UV curability, and difficulty in obtaining good adhesion.

[0083] As described above, in the comparative examples, when a poorly adhesive film is used as the substrate, it is not possible to obtain a hard-coated film that has the water repellency, antifouling properties, low friction performance, etc. provided by the hard coat, and also has excellent hard coat adhesion and hardness.

Claims

1. The relationship between the water contact angle A (°) and the arithmetic mean surface roughness B (nm) of the substrate film surface satisfies the relational expression 1: 0≦A−7.5×lnB−48. A hard coat layer containing at least an acrylate-based ultraviolet curable resin and a surface modifier is laminated on at least one surface of the substrate film, and the relationship between the number of functional groups C and the weight average molecular weight D satisfies the relational expression 2: C−7.1×logD+13.6<0 and 0≦C−5.4×logD+12.

8. The surface of the hard coat layer has a wavelength of 1730 cm when measured with an infrared spectrophotometer. －１ and the water contact angle of the surface of the hard coat layer is 90° or more.

2. 2. The hard coat film according to claim 1, wherein the surface modifier is at least one selected from the group consisting of a silicone-containing polymer and a fluorine-containing polymer.

3. 3. The hard coat film according to claim 1, wherein the amount of the surface modifier is 0.2 to 0.6 parts by mass relative to 100 parts by mass of the acrylate ultraviolet curable resin of the hard coat layer.

4. The hard coat layer further contains silica fine particles, and the surface of the hard coat layer has a wavelength of 1050 cm when measured with an infrared spectrophotometer. －１ 3. The hard coat film according to claim 1, wherein the hard coat film has an absorption peak at

5. 3. The hard coat film according to claim 1, wherein the static friction coefficient of the surface of the hard coat layer against a stainless steel material is 0.4 or less.

6. 3. The hard coat film according to claim 1, wherein the hard coat layer has a remaining rate of 75% or more as measured by the cross-cut method of JIS-K5600-5-6.

7. 3. The hard coat film according to claim 1, wherein the pencil hardness of the surface of the hard coat film is 2B or more.

8. 3. The hard coat film according to claim 1, wherein the thickness of the hard coat layer is 3 [mu]m or less.

9. 3. The hard coat film according to claim 1, wherein the substrate film is a polyaryl ether ketone film or a polyimide film.

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