TWI626156B - Hard coating film and manufacturing method thereof - Google Patents

Abstract

The present invention provides a hard-coated film with good writing feeling and excellent scratch resistance. In order to solve the above problems, a hard-coated film 1 is provided, which includes a base film 11 and a hard coating layer 12 formed on one side of the base film 11. On the surface of the hard coating layer 12, a hard felt core stylus pen with a pen tip diameter of 0.5 mm was scanned at a speed of 100 mm / min under a load of 150 g under a pressure of 250 mN or more.

Description

Hard coating film and manufacturing method thereof

The present invention relates to a hard-coated film for a touch panel using a stylus and a method for manufacturing the same.

In recent years, in various electronic devices, a touch panel having both a display device and an input means has been used. The surface of the touch panel is usually formed with a hard coating film having a hard coating layer in order to prevent damage.

Among the touch panels described above, in addition to input with a finger, there is also a touch panel with a stylus. Since the stylus is smaller than a finger, it can be accurately input. However, the display module of a touch panel is generally hard, and the surface of the touch panel on which the hard coating film is formed is also hard. Therefore, the writing feeling of the stylus pen is different from that when writing on paper with a pencil, a ballpoint pen, or the like, and it is difficult to say that it is good.

In order to solve the problem of writing feeling of the touch pen in the touch panel, in Patent Documents 1 and 2, a self-healing soft resin layer is laminated on the transparent substrate of the touch panel, thereby improving the writing feel of the stylus.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2003-15822

[Patent Document 2] Japanese Patent Laid-Open No. 2009-302013

However, since the self-repairing soft resin layer is prone to scratches, it does not have a hard coatability that can be tolerated in practical use, and therefore cannot be used as a hard coat layer. In addition, if the hard coat layer and the self-repairing soft resin layer are formed separately, the manufacturing process becomes complicated, and at the same time, the manufacturing cost increases.

The present invention has been made in view of such a situation, and an object of the present invention is to provide a hard-coated film that has a good writing feel and excellent scratch resistance.

In order to achieve the above object, first, the present invention provides a hard-coated film, which is a hard-coated film for a touch panel including a base film and a hard-coat layer formed on one side of the base film. The elastic modulus of the coating is 700 MPa to 7000 MPa. When the hard felt surface stylus with a pen tip diameter of 0.5 mm is scanned at a speed of 100 mm / minute under a pressure of 150 g on the surface of the hard coating layer, The sliding value of the pen resistance is 250 mN or more (Invention 1).

In the above invention (Invention 1), the hard coating layer has the above-mentioned elastic modulus, and the writing feeling of the stylus pen is imparted with a resistance feeling. In addition, the hard coating layer has the sliding value of the pen tip resistance, and the writing feeling of the stylus pen. The feeling of friction is given, and these feelings are coordinated with each other, so that the writing feel of the stylus is similar to that of writing on paper with a pencil and becomes good.

In the above invention (Invention 1), the hard coat layer is formed by curing a coating composition containing one or two or more kinds of polyfunctional (meth) acrylates, and at least one of the polyfunctional (meth) acrylates, It is preferred to have Number of alkylene oxide units (Invention 2).

In the said invention (invention 2), it is preferable that the quantity of the said alkylene oxide unit is 11 mass%-90 mass% in the total amount of the said polyfunctional (meth) acrylate (invention 3).

In the said invention (invention 2, invention 3), it is more preferable that the said coating composition contains a leveling agent (invention 4).

In the above invention (Invention 1 to Invention 4), the thickness of the hard coat layer is preferably 1 μm to 15 μm (Invention 5).

In the above invention (Invention 1 to Invention 5), the base film is preferably a polyethylene terephthalate film having a thickness of 15 μm to 300 μm as a main body (Invention 6).

Second, the present invention provides a method for manufacturing a hard-coated film, characterized in that, as a method for manufacturing the hard-coated film (Invention 2 to Invention 4), one side of the substrate film contains the coating composition. The coating solution is applied to form a coating film, and the coating film is irradiated with ultraviolet rays in an inert gas atmosphere to cure the coating film to form the hard coat layer (Invention 7).

The hard-coated film according to the present invention has a good writing feeling and excellent scratch resistance.

1‧‧‧hard-coated film

11‧‧‧ substrate film

12‧‧‧hard coating

FIG. 1 is a cross-sectional view of a hard-coated film according to an embodiment of the present invention.

FIG. 2 is a graph showing an example of a measurement result of a pen tip resistance.

Hereinafter, embodiments of the present invention will be described.

As shown in FIG. 1, the hard coat film 1 according to the present embodiment is composed of a base film 11 and a hard coat layer 12 formed on one surface of the base film 11. The hard coating film 1 is formed on the surface of a touch panel using a stylus.

Physical property

In the hard-coated film 1 according to this embodiment, the elastic modulus of the hard-coat layer 12 is 700 MPa to 7000 MPa. On the other hand, on the surface of the hard-coat layer 12 (the surface on the side not in contact with the base film 11), A stylus pen with a diameter of 0.5 mm and a stylus with a pen tip diameter of 0.5 mm can be scanned at a speed of 100 mm / min under a pressure of 150 g under a pressure of more than 250 mN.

In addition, the elastic modulus in this specification is a value measured using a micro surface hardness meter (a Shimadzu company's dynamic ultra micro hardness meter W201S is used in the test examples described later). In addition, the sliding value of the pen tip resistance refers to an average value of the pen tip resistance in a stable scanning state after the influence of the pen tip resistance displayed by the stylus at the start of scanning disappears. For example, the average value of the pen tip resistance with a scanning length of 10 mm to 40 mm in FIG. 2 is a sliding value.

If the hard coating layer 12 has the elastic modulus as described above, the writing feeling of the stylus pen is imparted with resistance, and if the hard coating layer 12 has the sliding value of the tip resistance as described above, the writing feeling of the stylus pen is Gives a feeling of friction. These feelings are coordinated with each other, so that the writing feeling of the stylus pen is similar to that when writing on paper with a pencil, and becomes good.

When the elastic modulus of the hard coating layer 12 exceeds 7000 MPa, the hard coating layer 12 becomes too hard, and the feeling of resistance as described above in the writing feeling of the stylus pen disappears, and the writing feeling decreases. In addition, if the elastic modulus of the hard coating layer 12 is less than 700 MPa Then, scratches easily occur, and the scratch resistance of the hard coating layer 12 is reduced.

On the other hand, if the sliding value of the pen tip resistance is less than 250 mN, the stylus pen slides too much on the surface of the hard coat layer 12 and the writing feeling is reduced. In addition, although the upper limit of the sliding value of the pen tip resistance is not particularly limited, if an upper limit is required, it is preferably about 600 mN from the viewpoint of the abrasion of the pen tip and / or the hard coating layer 12 of the stylus pen.

From the viewpoints described above, the elastic modulus of the hard coat layer 12 is preferably 1000 MPa to 6500 MPa, and particularly preferably 3000 MPa to 6000 MPa. The sliding value of the pen tip resistance is preferably 300 mN to 550 mN, and particularly preferably 350 mN to 450 mN.

In addition, if the above-mentioned physical properties are satisfied, the above-mentioned hard felt-core stylus can be confirmed to be a hard-coated film even when a stylus (for example, a polyacetal-core stylus) with a material and a different tip diameter is used. The effect of improved writing.

In addition, the hard coating film 1 described in this embodiment is preferably made of steel wool of # 0000 under a load of 250 g weight / cm ² , rubbing the surface of the hard coating layer 12 back and forth 10 cm at 10 cm without scratching, It is particularly preferable that rubbing back and forth 30 times under the same conditions does not cause scratches. By having such scratch resistance evaluated from the hardness of steel wool, when the hard coating film 1 is used on the surface of a touch panel, the occurrence of scratches on the hard coating layer 12 can be effectively suppressed.

2. Hard coating

In the present embodiment, the hard coat layer 12 of the hard coat film 1 can be formed of any material as long as the sliding value of the elastic modulus and the pen tip resistance can exhibit the above-mentioned physical properties. However, it is preferable to cure the coating composition C described below and form. With the coating composition C, the hard coat layer 12 satisfying the above-mentioned physical properties is easily formed.

The coating composition C in this embodiment contains one or two or more kinds of polyfunctional (meth) acrylates, and preferably further contains a leveling agent. In addition, in this specification, a (meth) acrylate means both an acrylate and a methacrylate. The same applies to other similar terms.

(1) Multifunctional (meth) acrylate

The coating composition C contains one or two or more kinds of polyfunctional (meth) acrylates as a curable main component. The polyfunctional (meth) acrylate is bridge-cured by irradiation with active energy rays. Since the polyfunctional (meth) acrylate is bridged and the bridging density is high, by using the polyfunctional (meth) acrylate, the formed hard coat layer 12 can obtain desired hardness and scratch resistance.

At least one of the above-mentioned polyfunctional (meth) acrylates is preferably a plurality of alkylene oxide units in the molecule. The polyfunctional (meth) acrylate has a plurality of alkylene oxide units in the molecule as described above, the cured product of the polyfunctional (meth) acrylate has a relatively low elastic modulus, and the elastic modulus of the hard coating layer 12 can be increased. Meet the above values.

The polyfunctional (meth) acrylate described above preferably has a structure having a unit equivalent to a polyol, an alkylene oxide unit being bonded to a hydroxyl portion thereof, or a (meth) acrylfluorenyl group being further bonded. The structure is not limited by the manufacturing method. Moreover, it is preferable that the said polyfunctional (meth) acrylate does not have a urethane bond etc. from a viewpoint of maintaining scratch resistance.

The alkylene oxide unit is preferably from about 1 to 8 carbon atoms, particularly preferably from about 1 to about 4 carbon atoms, and more preferably from about 2 to about 4 carbon atoms, from the viewpoint of improving both writing feeling and scratch resistance. Ethylene oxide.

Examples of the polyhydric alcohol include ethylene glycol and 1,3-propanediol. Alcohol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, hydroxypivalate neopentyl glycol, dicyclohexylpentanediol, dicyclohexylbutenediol, allyl Polyols having two hydroxyl groups such as cyclohexanediol, bis- (hydroxyalkyl) isocyanurate, bisphenol; trimethylolpropane, tri- (hydroxyalkyl) isocyanurate, etc. A polyhydric alcohol having 3 hydroxyl groups; a polyhydric alcohol having 4 hydroxyl groups such as pentaerythritol, di-trimethylolpropane; and a polyhydric alcohol having 6 hydroxyl groups such as di-pentaerythritol. These may be used alone or in combination of two or more. A polyol having three or more hydroxyl groups is preferred from the viewpoint of excellent scratch resistance, and a polyol having six or less hydroxyl groups is preferred from the viewpoint of improving the writing feeling.

The average number of moles of alkylene oxide in one molecule of the polyfunctional (meth) acrylate is preferably 5 to 20 mol, and particularly preferably 10 to 15 mol. The average number of moles referred to herein is an average value of the total number of moles of the alkylene oxide unit bonded to each hydroxyl group in one molecule of the polyol. In addition, from the viewpoint of the scratch resistance of the hard coat layer 12 and the transparency due to the affinity with the leveling agent, the number of reactive functional groups of the polyfunctional (meth) acrylate is preferably 2 to 10, and particularly preferably 3 ~ 6.

The coating composition C is preferably contained by mixing a polyfunctional (meth) acrylate having a plurality of alkylene oxide units and a polyfunctional (meth) acrylate having no alkylene oxide units. This makes it easy to control the elastic modulus of the hard coat layer 12 to the above-mentioned desired range.

Examples of the polyfunctional (meth) acrylate having no alkylene oxide unit include polyfunctional (meth) acrylates in which a (meth) acrylfluorenyl group is directly bonded to the polyol without an alkylene oxide unit. The polyfunctional (meth) acrylate having no alkylene oxide unit may be used alone or in combination of two or more. Use.

The mixing ratio (mass basis) of a polyfunctional (meth) acrylate having a plurality of alkylene oxide units and a polyfunctional (meth) acrylate having no alkylene oxide units is preferably 10:90 to 100: 0. It is particularly preferably 20:80 to 80:20, and more preferably 30:70 to 50:50.

The amount of the alkylene oxide unit in the total amount of the polyfunctional (meth) acrylate is preferably 11% to 90% by mass, particularly preferably 12% to 70% by mass, and still more preferably 14% to 50% by mass. . When the amount of the alkylene oxide unit is less than 11% by mass, the elastic modulus of the cured product of the polyfunctional (meth) acrylate is not easily reduced, and the elastic modulus of the hard coat layer 12 may be difficult to satisfy the above value. On the other hand, when the quantity of an alkylene oxide unit exceeds 90 mass%, the hard-coat layer 12 will become too soft, and scratch resistance may fall.

(2) Levelling agent

The coating composition C according to this embodiment preferably contains a leveling agent. The hard coat layer 12 thus formed has no line-like defects or spots, has a uniform film thickness, and exhibits an excellent appearance. At the same time, it is easy to adjust the sliding value of the pen tip resistance to the above range.

Examples of leveling agents include silicone leveling agents, fluorine leveling agents, acrylic leveling agents, and ethylene leveling agents. Among these, leveling properties and compatibility with other components are considered. Of these, silicone leveling agents and fluorine leveling agents are preferred. The leveling agents may be used singly or in combination of two or more.

The silicone-based levelling agent is preferably polydimethylsiloxane or modified polydimethylsiloxane, and as the modified polydimethylsiloxane, BYK-3550, a product of BYK Japan, and the like can be preferably cited. In addition, if modified polydimethylsiloxane If the modification rate is too high, in order to improve the appearance of the hard coat layer 12 obtained by exhibiting leveling properties, it is necessary to increase the amount of addition. As a result, the sliding property of the formed hard coating layer 12 becomes high, the sliding value of the pen tip resistance cannot satisfy the above-mentioned value, and the writing feeling of the stylus pen may be reduced.

As the fluorine-based levelling agent, a compound having a perfluoroalkyl group or a fluorinated alkenyl group as a main chain or a side chain is preferably exemplified. Examples of commercially available products include BYK Japan's product BYK-340, NEOS 'product FTERGENT650A, DIC's product MEGAFAC RS-75, and Osaka Organic Chemical Industry's product V-8FM, but are not limited thereto.

The blending ratio of the leveling agent is preferably 0.01 to 10 parts by mass, particularly preferably 0.05 to 5 parts by mass, and more preferably 100 parts by mass of the polyfunctional (meth) acrylate (or its cured product). It is 0.1 to 1 part by mass. If the leveling ratio of the leveling agent is in the above range, the writing feeling and scratch resistance of the stylus can be maintained, and the leveling effect can be fully obtained.

(3) Other ingredients

The coating composition C in this embodiment may contain various additives in addition to the above-mentioned components. Examples of the various additives include a photopolymerization initiator, an ultraviolet absorber, an oxidation inhibitor, a light stabilizer, an antistatic agent, a silane coupling agent, an anti-aging agent, a thermal polymerization inhibitor, a colorant, a surfactant, Storage stabilizer, plasticizer, lubricant, defoamer, organic filler, wettability improver, coating surface modifier, etc.

Examples of the photopolymerization initiator include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl ether, and benzoin isobutyl Ether, acetophenone, dimethylaminoacetophenone, 2,2-dimethoxy 2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-1-phenylpropane-1-one, 1-hydroxycyclohexyl Phenylketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholin-propane-1-one, 4- (2-hydroxyethoxy) phenyl-2- (Hydroxy-2-propyl) ketone, benzophenone, p-phenylbenzophenone, 4,4'-diethylaminobenzophenone, dichlorobenzophenone, 2-methylanthraquinone , 2-ethylanthraquinone, 2-tert-butylanthraquinone, 2-aminoanthraquinone, 2-methylxanthone, 2-ethylxanthone, 2-chloroxanthone, 2,4-bis Methylxanthone, 2,4-diethylxanthone, benzyldimethylketal, acetophenonedimethylketal, p-dimethylaminobenzoate and the like. These may be used alone or in combination of two or more.

The blending ratio of the photopolymerization initiator is usually selected from a range of 0.2 to 20 parts by mass based on 100 parts by mass of the polyfunctional (meth) acrylate (or a cured product thereof).

By coating and curing the coating composition C described above on the base film 11, a hard coat layer 12 satisfying the above-mentioned physical properties can be formed.

The thickness of the hard coat layer 12 is preferably 1 μm to 15 μm, and particularly preferably 2 μm to 10 μm. If the thickness of the hard coating layer 12 is in the above range, the scratch resistance and the good writing feeling of the stylus pen can be effectively exerted.

3. Substrate film

The base film 11 may be appropriately selected from a base film for a touch panel suitable for using a stylus, and a plastic film having a good affinity with the hard coat layer 12 is preferably selected.

Examples of the plastic film include polyester films such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; polyethylene films and polypropylene films Polyolefin film; Cellophane , Diacetyl cellulose film, triethyl cellulose film, cellulose ethyl butyrate film, polyvinyl chloride film, polyvinylidene chloride film, polyvinyl alcohol film, ethylene-vinyl acetate copolymer film , Polystyrene film, polycarbonate film, polymethylpentene film, polyfluorene film, polyetherketone film, polyetherfluorene film, polyfluorine film, fluororesin film, polyfluorene film, acrylic resin film Plastic film such as polyurethane resin film, norbornene polymer film, cyclic olefin polymer film, cyclic conjugated diene polymer film, vinyl alicyclic hydrocarbon polymer film, or these laminated films. Among them, a polyethylene terephthalate film, a polycarbonate film, a norbornene polymer film, and the like that can maintain the stylus writing feeling in a good combination with the hard coating layer 12 are preferred, and particularly preferred It is a polyethylene terephthalate film.

In addition, the substrate film 11 may be subjected to a primer treatment on one or both sides as needed for the purpose of improving adhesion to a layer (hard coat layer 12, adhesive layer, etc.) formed on the surface thereof. The surface treatment is performed according to an oxidation method, an uneven method, and the like. Examples of the oxidation method include corona discharge treatment, chromate treatment, flame treatment, hot air treatment, and ozone. Ultraviolet treatment and the like include, for example, a sandblasting method, a solvent treatment method, and the like as the unevenness method. These surface treatment methods can be appropriately selected according to the type of the base film 11. As an example, it is preferable to use a plastic film, particularly a polyethylene terephthalate film, which forms an easily-adhesive layer by a primer treatment.

The thickness of the base film 11 is preferably 15 μm to 300 μm, particularly preferably 30 μm to 200 μm, and still more preferably 90 μm to 150 μm.

4. Manufacturing method of hard coating film

The hard coating film 1 described in this embodiment can be obtained by applying the hard coating film 12 A coating composition, particularly a coating composition C, and a coating solution containing a solvent as needed are preferably applied and cured on the base film 11 to form a hard coat layer 12.

The solvent can be used for the purpose of improving the workability, adjusting the viscosity, adjusting the solid content concentration, and the like. If the solvent is a polyfunctional (meth) acrylate, a leveling agent, etc., it can be used without any limitation.

Specific examples of the solvent include alcohols such as methanol, ethanol, isopropanol, butanol, and octanol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; Ethyl acetate, butyl acetate, ethyl lactate, γ-butyrolactone, etc .; ethylene glycol monomethyl ether (methyl cellosolve), ethylene glycol monoethyl ether (ethyl cellosolve), two Glycol monobutyl ether (butyl cellosolve), propylene glycol monomethyl ether, and other ethers; aromatic hydrocarbons such as benzene, toluene, and xylene; dimethylformamide, dimethylacetamide, and N-methylpyrrolidone And so on.

The coating composition coating liquid can be applied by a common method. For example, it can be performed by a bar coating method, a blade coating method, a roll coating method, a plate coating method, a die coating method, or a gravure coating method. When the coating liquid of the coating composition is applied, the coating film is preferably dried at 40 ° C. to 120 ° C. for about 30 seconds to 5 minutes.

Here, when the coating composition contains a leveling agent, the coating film coated with the coating composition has no line-like defects or spots, and therefore, a hard coating layer 12 having a uniform film thickness and excellent appearance can be formed.

When the coating composition is active energy ray-curable like the coating composition C, curing of the coating composition can be performed by irradiating the coating film of the coating composition with active energy rays such as ultraviolet rays and electron beams. The irradiation of ultraviolet rays can be performed by a high-pressure mercury lamp, a Fusion H lamp, a xenon lamp, and the like. The irradiation amount of ultraviolet rays is preferably 50 mW / cm ² to 1000 mW / cm ² and the light amount is about 50 mJ / cm ² to 1000 mJ / cm ² . On the other hand, the irradiation of the electron beam can be performed by an electron beam accelerator or the like, and the irradiation amount of the electron beam is preferably about 10 krad to 1,000 krad.

It is preferable to irradiate the coating film of the said coating composition with an active energy ray in an inert gas atmosphere. The presence of oxygen during active energy ray irradiation may cause poor curing of the coating composition. However, if the active energy ray is irradiated under the inert gas atmosphere as described above, the coating composition can be cured well without being hindered by oxygen. The hard coating layer 12 thus formed is excellent in scratch resistance.

Examples of the inert gas include nitrogen, argon, and helium. Among them, nitrogen and argon are preferred, and nitrogen is particularly preferred. The oxygen concentration in the inert gas atmosphere is preferably 5% or less, particularly preferably 3% or less, and still more preferably 2% or less.

5. Other

In the hard-coated film 1 according to this embodiment, the hard-coat layer 12 is the outermost surface, and preferably has a base film 11 and a hard-coat layer 12, between the hard-coat layer 12 and the base film 11, or with the base material. The surface on the side where the hard coat layer 12 of the film 11 does not contact may have another layer. For example, an adhesive layer may be formed on the surface of the side not in contact with the hard coat layer 12 of the base film 11, and a release sheet may be laminated on the adhesive layer.

The adhesive constituting the adhesive layer is not particularly limited, and known adhesives such as an acrylic adhesive, a rubber adhesive, and a silicone adhesive can be used.

Arithmetic level of hard coat layer 12 of hard coat film 1 according to this embodiment The average surface roughness (Ra) is preferably 0.1 μm or less, particularly preferably 0.05 μm or less, and still more preferably 0.01 μm or less. When the arithmetic average surface roughness (Ra) is within the above range, the hard coat layer 12 can exhibit excellent transparency and is suitable for use as a touch panel. The arithmetic average surface roughness (Ra) in the present specification is obtained from a roughness curve measured using a contact-type roughness meter (a Mitsubishi Corporation product SV3000S4 is used in the test example) based on JIS B0601-1994.

The embodiments described above are described for easy understanding of the present invention, and are not described to limit the present invention. Therefore, each element disclosed in the above embodiment includes all design changes and equivalents belonging to the technical scope of the present invention.

For example, in the hard coating film 1, another layer may be interposed between the base film 11 and the hard coating layer 12.

[Example]

Hereinafter, the present invention will be described in more detail through examples and the like, but the scope of the present invention is not limited by these examples and the like.

[Example 1]

As a polyfunctional (meth) acrylate having a plurality of ethylene oxide units, ethoxylated dipentaerythritol hexaacrylate (manufactured by Shin Nakamura Chemical Co., Ltd., NK ester A-DPH-12E, ethylene oxide in one molecule) Existing amount of unit: 12 mol) 50 parts by mass (represents a solid content conversion value. The same applies to other components below.); As a polyfunctional (meth) acrylate having no alkylene oxide unit, pentaerythritol triacrylate (Manufactured by Shin Nakamura Chemical Co., Ltd., NK ester A-TMM-3L) 50 parts by mass; as a photopolymerization initiator, 10 parts by mass of 1-hydroxycyclohexylphenyl ketone (IRUGACURE 184, manufactured by BASF Corporation); as level dyeing Agent, modified polysiloxane 0.1 mass part of an acrylic polymer (silicone leveling agent; BYK-3550 manufactured by BYK) was mixed, and the coating composition was obtained. This coating composition was diluted with propylene glycol monomethyl ether to prepare a coating liquid having a solid content concentration of 30%. In addition, according to the above-mentioned combination, the amount of ethylene oxide units in the total amount of the polyfunctional (meth) acrylate was 24% by mass.

On the side of the easily-adhesive layer of the polyester film (COSMO SHINE A4300, thickness: 125 μm) with an easily-adhesive layer as the base film, the above-mentioned wire for a coating fluid was applied. # 14 was applied and dried at 70 ° C for 1 minute. Next, in a nitrogen atmosphere (with an oxygen concentration of 1% or less), an ultraviolet irradiation device (manufactured by GS YUASA, a nitrogen purge small transport UV irradiation device CSN2-40) was used to irradiate ultraviolet rays under the following conditions to form a 5 μm-thick film. Hard coating to obtain a hard coating film.

[UV irradiation conditions]

． Light source: high pressure mercury lamp

． Bulb power: 1.4kW

． Conveyor speed: 1.2m / min

． Illumination: 100mW / cm2

． Light quantity: 240mJ / cm2

[Example 2]

In addition to ethoxylated dipentaerythritol hexaacrylate (manufactured by Shin Nakamura Chemical Co., Ltd., NK ester A-DPH-12E, which is a polyfunctional (meth) acrylate having a plurality of ethylene oxide units, ethylene oxide in one molecule Existing amount of alkane unit: 12 moles) The blending amount was changed to 30 parts by mass, and pentaerythritol triacrylate (manufactured by Shin Nakamura Chemical Co., Ltd., which is a polyfunctional (meth) acrylate having no alkylene oxide unit, was prepared, NK The blending amount of ester A-TMM-3L) was changed to 70 parts by mass to form a hard coat layer, and a hard coat film was produced in the same manner as in Example 1. In addition, according to the above-mentioned combination, the amount of ethylene oxide units in the total amount of the polyfunctional (meth) acrylate was 15% by mass.

[Example 3]

In addition to ethoxylated dipentaerythritol hexaacrylate (manufactured by Shin Nakamura Chemical Co., Ltd., NK ester A-DPH-12E, which is a polyfunctional (meth) acrylate having a plurality of ethylene oxide units, ethylene oxide in one molecule Existing amount of alkane unit: 12 moles) The blending amount was changed to 100 parts by mass, and pentaerythritol triacrylate (manufactured by Shin Nakamura Chemical Co., Ltd., NK ester A, which is a polyfunctional (meth) acrylate having no alkylene oxide unit) -TMM-3L) was changed to 0 parts by mass to form a hard coat film, and a hard coat film was produced in the same manner as in Example 1. In addition, according to the above arrangement, the amount of ethylene oxide units in the total amount of the polyfunctional (meth) acrylate was 48% by mass.

[Example 4]

In addition to using a perfluoropolyether-containing acrylate compound (fluorine leveling agent; DIC Corporation, MEGAFAC RS-75) as a leveling agent, the blending amount is 0.1 parts by mass to form a hard coat layer. In the same manner as in Example 1, a hard-coated film was produced.

[Comparative Example 1]

In addition to ethoxylated dipentaerythritol hexaacrylate (manufactured by Shin Nakamura Chemical Co., Ltd., NK ester A-DPH-12E, which is a polyfunctional (meth) acrylate having a plurality of ethylene oxide units, ethylene oxide in one molecule Existing amount of alkane units: 12 moles) The blending amount was changed to 0 parts by mass, and the polyfunctional ( The blending amount of pentaerythritol triacrylate (meth) acrylate (manufactured by Shin Nakamura Chemical Co., Ltd., NK ester A-TMM-3L) was changed to 100 parts by mass to form a hard coat layer. The same operation as in Example 1 was performed to manufacture Hard-coated film. In addition, according to the above arrangement, the amount of ethylene oxide units in the total amount of the polyfunctional (meth) acrylate is 0% by mass.

[Comparative Example 2]

In addition to ethoxylated dipentaerythritol hexaacrylate (manufactured by Shin Nakamura Chemical Co., Ltd., NK ester A-DPH-12E, which is a polyfunctional (meth) acrylate having a plurality of ethylene oxide units, ethylene oxide in one molecule Existing amount of alkane units: 12 moles) The blending amount was changed to 20 parts by mass, and pentaerythritol triacrylate (manufactured by Shin Nakamura Chemical Co., Ltd., NK ester A, which is a polyfunctional (meth) acrylate having no alkylene oxide units) was used. -TMM-3L) The blending amount was changed to 80 parts by mass to form a hard coat layer, and a hard coat film was produced in the same manner as in Example 1. In addition, according to the above arrangement, the amount of ethylene oxide units in the total amount of the polyfunctional (meth) acrylate is 10% by mass.

[Comparative Example 3]

In addition to replacing polyfunctional (meth) acrylates having a plurality of ethylene oxide units and polyfunctional (meth) acrylates having no alkylene oxide units, a self-healing UV curable resin (manufactured by NOF Corporation, BLEMMER TA-604AU) 100 parts by mass, except for forming a hard coat layer, the same operation as in Example 1 was performed to produce a hard coat film.

[Comparative Example 4]

In addition to using a polyether-modified polydimethylsiloxane (silicone leveling agent; BYK company, BYK-UV3500) with an acryl group as the leveling agent, The compounding amount was 0.1 parts by mass to form a hard coat film except that a hard coat layer was formed. The same operation as in Example 1 was performed.

[Test Example 1] (Measurement of Elastic Modulus)

About the hard-coat layer of the hard-coated film manufactured in the Example and the comparative example, the elasticity modulus (MPa) was measured using the micro surface hardness meter (made by Shimadzu, dynamic ultra-micro hardness meter W201S). The results are shown in Table 1.

[Test Example 2] (Measurement of Pen Tip Resistance)

For the hard-coated surfaces of the hard-coated films produced in the examples and comparative examples, a universal testing machine (TENSILON, manufactured by ORIENTEC Corporation) and a stylus pen were used to contact the film surface with the pen tip under a load of 150 g. The test was performed under the condition of scanning at a speed of 100 mm / min. Then, in the obtained test chart, the sliding value (mN) of the nib resistance was obtained. In addition, as the stylus, a stylus with a hard felt tip (wacom, ACK-2003, nib diameter: 0.5 mm) was used. The results are shown in Table 1.

[Test Example 3] (Evaluation of Writing Feeling)

The hard coating films produced in the examples and comparative examples were placed on a glass substrate with the hard coating side facing up. On the hard-coated surface of the hard-coated film, the same stylus as in Test Example 1 and a polyacetal-core stylus (pen tip diameter: 0.4 mm) were used to evaluate the writing feeling. In the evaluation, a sheet of paper (manufactured by KOKUYO Technology Co., Ltd., CAMPUS NOTE A lead wire NO-201A) was written with a pencil (MITSUBISHI PENCIL UNI B, manufactured by Mitsubishi Pencil Co., Ltd.) with a pen pressure of about 150 g. The writing with a similar writing feeling at that time was good, and the writing with a large gap from the writing feeling was bad. In addition, the evaluation was performed by three panelists. When all three felt good, it was considered good, and when only one felt bad, it was considered bad. Show results 于 表 1。 In Table 1.

[Test Example 4] (Scratch Resistance Evaluation: Steel Wool Hardness)

The hard-coated surfaces of the hard-coated films produced in the examples and comparative examples were rubbed back and forth 10 times and 30 times at 10 cm using a steel wool of # 0000 under a load of 250 g weight / cm ² . The surface of this hard-coat layer was confirmed with the naked eye under a 3-wavelength fluorescent lamp, and evaluation was performed based on the following criteria. The results are shown in Table 1.

(Double-circle): Scratches were not recognized even when back and forth 30 times.

○: Scratches were not confirmed during 10 round trips, but scratches were confirmed during 30 round trips.

×: Scratches were also confirmed in 10 round trips.

[Test Example 5] (Measurement of surface roughness)

The arithmetic average surface roughness (Ra; unit: μm) of the hard coat surface of the hard coat film manufactured from the examples and comparative examples is based on JIS B0601-1994, using a contact-type roughness meter (manufactured by Mitutoyo Corporation, SV3000S4) Obtained by measuring the roughness curve. The results are shown in Table 1.

As can be seen from Table 1, the hard-coated film produced in the examples was written It has a good feel and excellent scratch resistance.

[Industrial availability]

The hard-coated film of the present invention is suitably used as a surface layer of a touch panel using a stylus.

Claims (7)

A hard-coated film comprising a base film and a hard-coated film for a touch panel having a hard-coat layer formed on one surface of the base film, wherein the hard-coat layer has an elastic modulus of 700 MPa to 7000 MPa. For the surface of the hard coating layer, a stylus pen with a pen tip diameter of 0.5 mm and a pressure of 150 g under a pressure of 100 mm / min is used to scan the pen tip resistance and the sliding value is more than 250 mN. The hard coating film according to item 1 of the scope of the patent application, wherein the hard coating layer is formed by curing a coating composition containing one or more polyfunctional (meth) acrylates, and the polyfunctional (form At least one type of acrylate), and has a plurality of alkylene oxide units in the molecule. The hard coating film according to item 2 of the scope of the patent application, wherein the amount of the alkylene oxide unit in the total amount of the polyfunctional (meth) acrylate is 11% to 90% by mass. The hard coating film according to item 2 of the patent application scope, wherein the coating composition further contains a leveling agent. The hard coating film according to item 1 of the scope of patent application, wherein the thickness of the hard coating layer is 1 μm to 15 μm. The hard coating film according to item 1 of the scope of the patent application, wherein the base film mainly comprises a polyethylene terephthalate film having a thickness of 15 μm to 300 μm. A method for manufacturing a hard-coated film, characterized in that, as a method for manufacturing a hard-coated film according to any one of claims 2 to 4, the coating composition is contained on one side of the substrate film. The coating solution is applied to form a coating film, and the coating film is irradiated with ultraviolet rays in an inert gas atmosphere to cure the coating film to form the hard coat layer.