KR20190140839A - Hard coat film and transparent conductive film - Google Patents

Abstract

The present invention relates to a hard coat film which is equipped with a transparent base material and a hard coat layer in order in the thickness direction, wherein the hard coat layer contains a resin matrix and particles. In addition, the hardness of the hard coat layer measured by a nanoindentation method is 0.320 to 0.520 GPa and the pencil hardness of a hard-coat layer is B or less, thereby having excellent flex resistance and scratch resistance, and excellent flexibility.

Description

Hard coat film and transparent conductive film {HARD COAT FILM AND TRANSPARENT CONDUCTIVE FILM}

The present invention relates to a hard coat film and a transparent conductive film, and more particularly, to a hard coat film and a transparent conductive film having the same.

Conventionally, the hard coat film which has a hard coat layer in the single side | surface of a transparent resin substrate is known.

For example, the hard coat film provided with the hard-coat layer whose elasticity modulus is 2.1-5.0 GPa is proposed (for example, refer Unexamined-Japanese-Patent No. 2014-25061).

By the way, although excellent bending resistance is calculated | required by a hard-coat layer, in the hard-coat film of Unexamined-Japanese-Patent No. 2014-25061, since the elasticity modulus of a hard-coat layer is high as 2.1-5.0 kPa, the said request can fully be satisfied. none.

On the other hand, the hard coat film also requires the outstanding scratch resistance.

In addition, the hard coat film is also required to be flexible while having excellent flex resistance and scratch resistance.

The present invention provides a hard coat film having excellent flex resistance and scratch resistance and excellent flexibility, and a transparent conductive film having the same.

This invention (1) is equipped with a transparent base material and a hard-coat layer in order in the thickness direction, The said hard-coat layer contains a resin matrix and particle | grains, The said hard-coat layer measured by the nanoindentation method The hard coat film of the hardness of 0.320 kPa or more and 0.520 kPa or less, and the pencil hardness of the said hard-coat layer is B or less.

This invention (2) contains the hard coat film as described in (1) whose thickness of the said hard coat layer is 3 micrometers or less.

This invention (3) contains the hard-coat film as described in (1) or (2) whose arithmetic mean roughness Ra of the said hard-coat layer is 3 nm or more and 14 nm or less.

This invention (4) contains the hard coat film in any one of (1)-(3) whose material of the said transparent base material is a cycloolefin polymer.

This invention (5) contains the hard coat film as described in any one of (1)-(4), a transparent conductive film provided with an optical adjustment layer, and a transparent conductive layer in order in the thickness direction.

The hard coat film and the transparent conductive film of the present invention have excellent flexibility and scratch resistance and excellent flexibility because the hardness of the hard coat layer is 0.320 kPa or more and 0.520 kPa or less, and the pencil hardness of the hard coat layer is B or less. do.

BRIEF DESCRIPTION OF THE DRAWINGS The cross section of one Embodiment of the hard coat film of this invention is shown.
FIG. 2: shows sectional drawing of the transparent conductive film provided with the hard coat film shown in FIG.

One embodiment of the hard coat film of this invention is demonstrated with reference to FIG.

The hard coat film 1 has one side and the other side (two main surfaces) which are opposed to each other at intervals in the thickness direction. One side and the other side of the hard coat film 1 are flat surfaces parallel to each other. The hard coat film 1 has a substantially film shape extending in the plane direction orthogonal to the thickness direction.

The hard coat film 1 is a component provided with the transparent conductive film 6 (refer FIG. 2) mentioned later, for example, and is not the transparent conductive film 6, for example. That is, the hard coat film 1 is a component for producing the transparent conductive film 6, does not include the optical adjustment layer 4 and the transparent conductive layer 5, it is circulated by the component alone, and is used industrially. Possible device.

The hard coat film 1 is equipped with the transparent base material 2 and the hard coat layer 3 in order toward the thickness direction one side. That is, the hard coat film 1 is equipped with the transparent base material 2 and the hard coat layer 3 arrange | positioned at the thickness direction one surface of the transparent base material 2. Moreover, preferably, the hard coat film 1 consists only of the transparent base material 2 and the hard coat layer 3.

The transparent base material 2 forms the other side of the hard coat film 1. Specifically, the transparent base material 2 is a support material which ensures the mechanical strength of the hard coat film 1. The transparent base material 2 has a film shape extending in the plane direction. The transparent base material 2 has one side and the other side which oppose each other at intervals in the thickness direction. One side and the other side of the transparent base material 2 are flat surfaces parallel to each other. The thickness direction other surface of the transparent base material 2 is exposed to the thickness direction other side.

If the material of the transparent base material 2 is transparent, it will not specifically limit. As a material of the transparent base material 2, resin (including a polymer) is mentioned, for example. As the resin, for example, polyester resins such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, for example, (meth) acrylic resins such as polymethacrylate (acrylic resin and / or methacryl) Resins), for example, olefin resins such as polyethylene, polypropylene, cycloolefin polymers (COP), for example, polycarbonate resins, for example, polyethersulfone resins, for example, polyarylate resins, for example Examples thereof include melamine resins such as polyamide resins such as polyimide resins such as cellulose resins such as polystyrene resins such as norbornene resins. These resins can be used alone or in combination of two or more. From the standpoint of securing excellent optical properties (including transparency), an olefin resin is preferable, and COP is more preferable.

COP is excellent in optical characteristics (isotropic) compared with polyester resin. On the other hand, COP has low mechanical strength (it is easy to crack) compared with polyester resin. However, since this hard coat film 1 is provided with the hard coat layer 3 which has desired hardness and pencil hardness, even if the mechanical strength of the transparent base material 2 is low, the hard coat film 1 will not be mechanical strength. Can greatly suppress the occurrence of cracks (cracking).

The total light transmittance (JIS K 7375-2008) of the transparent substrate 2 is, for example, 80% or more, preferably 85% or more.

The thickness of the transparent base material 2 is the length between one side and the other side (it is the same also in each following layer), Specifically, it is 2 micrometers or more, Preferably it is 20 micrometers or more, and is an example For example, it is 300 micrometers or less, Preferably it is 200 micrometers or less.

The hard coat layer 3 forms one surface of the hard coat film 1. Specifically, the hard coat layer 3 is a hard layer which secures excellent scratch resistance while giving excellent hard resistance to the hard coat film 1. Moreover, the hard coat layer 3 is also an anti blocking layer which provides blocking resistance to the hard coat film 1. The hard coat layer 3 has a film shape extending in the surface direction. The hard coat layer 3 has one side and the other side opposed to each other at intervals in the thickness direction. The other side of the hard coat layer 3 is in contact with one side of the transparent base material 2. One surface of the hard coat layer 3 is exposed to the thickness direction one side of the hard coat film 1, for example, and has a fine uneven | corrugated shape (not shown in FIG. 1).

The hard coat layer 3 contains resin and particle | grains. The hard coat layer 3 preferably contains only resin and particles. Specifically, the material of the hard coat layer 3 is a composition containing resin and particles.

It will not specifically limit, if it is transparent resin, For example, curable resin, a thermoplastic resin, etc. are mentioned, Preferably, curable resin, More preferably, photocurable resin is mentioned. As photocurable resin, an acrylic resin, an epoxy resin, a silicone resin etc. are mentioned, for example, Preferably, an acrylic resin is mentioned from a viewpoint of ensuring the outstanding optical characteristic and the outstanding mechanical strength. These resins can be used alone or in combination of two or more.

It does not specifically limit as a material of particle | grains, If it is transparent, it will not specifically limit, For example, an organic material and an inorganic material are mentioned. As an organic material, polymers, such as an acrylic polymer and polystyrene, are mentioned, for example, Preferably, an acrylic polymer is mentioned. Examples of the inorganic material include silica, for example, metal oxides made of zirconium oxide, titanium oxide, zinc oxide, tin oxide, and the like, and carbonates such as calcium carbonate and the like. Preferably, silica is mentioned. These materials can be used alone or in combination of two or more.

The shape of the particles is not particularly limited, and examples thereof include a substantially spherical shape, a substantially needle shape, a substantially plate shape, an indefinite shape, and the like, and preferably a substantially spherical shape.

The average value of the maximum length of the particles (average particle diameter if it is approximately spherical) is preferably relatively small, more preferably nano size. Specifically, the average value of the maximum length of the particles is, for example, 100 nm or less, preferably 80 nm or less, more preferably 60 nm or less, and for example, 1 nm or more, preferably 5 It is nm or more, More preferably, it is 10 nm or more.

If the average value of the maximum length of particle | grains is below the said upper limit, the arithmetic mean roughness Ra of one side of the hard-coat layer 3 mentioned later can be easily and reliably set to a desired range.

If the average value of the maximum length of particle | grains is more than the said minimum, excellent anti blocking property can be provided to the hard coat film 1.

In addition, the hard coat layer 3 is formed of the composition described above, and the hard coat layer 3 is provided with a resin matrix and particles dispersed therein.

The mass part number of particle | grains is 0.1 mass part or more, Preferably it is 1 mass part or more with respect to 100 mass parts of resin, For example, 75 mass parts or less, Preferably it is 55 mass parts or less to be.

The hardness of the hard coat layer 3 is 0.320 kPa or more, preferably 0.350 kPa or more, and more preferably 0.360 kPa or more. When the hardness of the hard coat layer 3 is less than the above lower limit, the hard coat film 1 cannot secure excellent scratch resistance.

Moreover, the hardness of the hard-coat layer 3 is 0.520 kPa or less, Preferably it is 0.500 kPa or less, More preferably, it is 0.450 kPa or less, More preferably, it is 0.400 kPa or less, Especially preferably, it is 0.370 kPa or less. When the hardness of the hard coat layer 3 exceeds the above upper limit, the hard coat film 1 cannot secure excellent bending resistance.

Hardness of the hard coat layer 3 is 23 degreeC indentation hardness measured by the nanoindentation method, Specifically, it is obtained by indenting a nanoindenter (indenter) in the hard coat layer 3 at 23 degreeC. Indentation hardness. The detail of the measuring method of hardness is described in the following Example.

Moreover, the pencil hardness of the hard-coat layer 3 is B or less, Preferably it is 2B or less, More preferably, it is 3B or less, More preferably, it is 4B or less, Especially preferably, it is 5B or less. In addition, the pencil hardness of the hard-coat layer 3 is 10B or more, for example, 9B or more.

When the pencil hardness of the hard coat layer 3 exceeds (above B) the said upper limit (B), the outstanding flexibility of the hard coat layer 3 cannot be ensured.

The pencil hardness of the hard coat layer 3 is measured according to JIS K5600-5-4 "scratch hardness (pencil method)" (1999).

The arithmetic mean roughness Ra of one side of the hard coat layer 3 is, for example, 1 nm or more, preferably 3 nm or more, more preferably 5 nm or more, and for example, 20 nm or less, Preferably it is 14 nm or less, More preferably, it is 12 nm or less.

If the arithmetic mean roughness Ra of one side of the hard-coat layer 3 is more than the said minimum, excellent anti blocking property can be provided to the hard-coat film 1.

If the arithmetic mean roughness Ra of one side of the hard-coat layer 3 is below the said upper limit, the raise of the haze of the hard-coat film 1 can be suppressed, and excellent transparency can be ensured.

Arithmetic mean roughness Ra of the hard coat layer 3 is measured according to JISB0601 (2013).

The hard coat layer 3 is preferably relatively thin. Specifically, the thickness of the hard coat layer 3 is, for example, less than 10 µm, preferably 9 µm or less, more preferably 7 µm or less, still more preferably 5 µm or less, particularly preferably 3 Or less, most preferably 2 m or less. If the thickness of the hard-coat layer 3 is below the said upper limit, the outstanding bending resistance can be ensured.

Moreover, the thickness of the hard-coat layer 3 is 0.001 micrometer or more, Preferably it is 0.01 micrometer or more, More preferably, it is 0.1 micrometer or more, More preferably, it is 0.5 micrometer or more. The scratch resistance of the hard coat layer 3 can be improved as long as the thickness of the hard coat layer 3 is more than the said minimum.

The thickness of the hard coat layer 3 is measured using the instantaneous multi-metering system "MCPD2000" (brand name) by the Otsuka Electronics company.

In the case of 101 micrometers in thickness, the haze of the hard-coat film 1 is less than 0.5, Preferably it is 0.40 or less, More preferably, it is 0.30 or less, More preferably, it is 0.20 or less, Especially preferably, it is 0.15. It is below and it is usually 0.01 or more.

When the haze of the hard coat film 1 is less than the above upper limit, the hard coat film 1 is excellent in transparency.

The thickness of the hard coat film 1 is 150 micrometers or less, Preferably it is 125 micrometers or less, For example, 5 micrometers or more, Preferably it is 10 micrometers or more.

To manufacture this hard coat film 1, for example, first, the transparent base material 2 is prepared, and the composition is then wetted on one side in the thickness direction of the transparent base material 2, for example, by wet. To place.

Specifically, first, the coating liquid (varnish) which diluted the composition with the solvent is prepared. The mixture (commercially available) in which the particles are dispersed in the resin in advance can be prepared (prepared) as a coating liquid, or the particles and the resin can be mixed to disperse the particles in the resin and prepared. In addition, an initiator can be added to a coating liquid as needed, or resin to which the initiator was previously added can also be used.

Subsequently, the coating liquid (varnish) is applied to one side in the thickness direction of the transparent base material 2. Thereafter, the solvent is removed by heating, and then the curable resin is cured when the composition contains the curable resin. Thereby, the hard-coat layer 3 in which particle | grains are disperse | distributed to a resin matrix is formed.

Thereby, the hard-coat layer 3 is formed in the thickness direction one surface of the transparent base material 2.

Thereby, the hard coat film 1 provided with the transparent base material 2 and the hard-coat layer 3 is manufactured.

This hard coat film 1 is used for each industrial use, for example, it is used for optical uses, such as a transparent conductive film and a light control film, and also an electronic shield use. Preferably, it is used for an optical use, More preferably, a transparent conductive film.

Next, the transparent conductive film 6 provided with the hard coat film 1 is demonstrated with reference to FIG.

The transparent conductive film 6 has one side and the other side (two main surfaces) which are opposed to each other at intervals in the thickness direction. One side and the other side of the transparent conductive film 6 are flat surfaces parallel to each other. The transparent conductive film 6 has a substantially film shape extending in the plane direction. The transparent conductive film 6 is one component, such as a base material for touch panels, a light control panel, etc. which are equipped with an optical device (for example, an image display apparatus, a light control apparatus), for example, and is not an optical device. That is, the transparent conductive film 6 is a component for manufacturing an optical device, etc., and is a device which is distributed by the component alone and does not contain image display elements, such as an LCD module, and light sources, such as LED, and is an industrially usable device. .

This transparent conductive film 6 is equipped with the hard coat film 1, the optical adjustment layer 4, and the transparent conductive layer 5 in order toward the thickness direction one side. Specifically, the transparent conductive film 6 has the transparent base material 2, the hard-coat layer 3, the optical adjustment layer 4, and the transparent conductive layer 5 in order in one direction toward the thickness direction. Equipped. Preferably, the transparent conductive film 6 consists of the transparent base material 2, the hard-coat layer 3, the optical adjustment layer 4, and the transparent conductive layer 5 only.

After the transparent conductive layer 5 is formed in the wiring pattern in a subsequent step, the optical adjustment layer 4 is transparent so that the difference between the non-pattern portion and the pattern portion is not recognized (that is, suppresses the visibility of the wiring pattern). It is a layer (index matching layer) which adjusts the optical physical property of the film 6. The optical adjustment layer 4 has the film shape extended in a surface direction, and has the one side and the other surface which oppose each other at intervals in the thickness direction. Examples of the material of the optical adjustment layer 4 include the above-mentioned resins (which do not contain particles), the above-described compositions (containing particles), and the like. The thickness of the optical adjustment layer 4 is, for example, 30 nm or more, preferably 80 nm or more, and, for example, 150 nm or less, preferably 130 nm or less.

The transparent conductive layer 5 is a conductive layer for forming in a wiring pattern in a subsequent process and forming a pattern part. The transparent conductive layer 5 forms the thickness direction one surface of the transparent conductive film 6. The transparent conductive layer 5 has a film shape (including a sheet shape) extending in the surface direction, and has one side and the other side opposed to each other at intervals in the thickness direction.

As a material of the transparent conductive layer 5, it selects from the group which consists of In, Sn, Zn, Ga, Sb, Ti, Si, Zr, Mg, Al, Au, Ag, Cu, Pd, W, for example. The metal oxide containing at least 1 type of metal is mentioned. As needed, the metal oxide shown to the said group can be further dope to a metal oxide. As a material, Preferably, indium tin composite oxide (ITO), antimony tin composite oxide (ATO), etc. are mentioned.

The thickness of the transparent conductive layer 5 is, for example, 10 nm or more, preferably 20 nm or more, and, for example, 35 nm or less, preferably 30 nm or less.

The thickness of the transparent conductive film 6 is 150 micrometers or less, Preferably it is 125 micrometers or less, For example, 5 micrometers or more, Preferably it is 10 micrometers or more.

In order to manufacture the transparent conductive film 6, the optical adjustment layer 4 and the transparent conductive layer 5 are made to a well-known method in the thickness direction one side of the hard-coat layer 3 of the hard coat film 1 mentioned above. In order.

And since the hardness of the hard-coat layer 3 is 0.320 kPa or more in this hard-coat film 1 and the transparent conductive film 6, excellent scratch resistance can be ensured.

Moreover, since the hardness of the hard-coat layer 3 is 0.520 GPa or less, the outstanding bending resistance can be ensured.

In addition, since the pencil hardness of the hard-coat layer 3 is B or less, flexibility can be ensured, while having the outstanding bending resistance and scratch resistance.

Moreover, when the thickness of the hard-coat layer 3 is 3 micrometers or less, the outstanding bending resistance can be ensured.

Moreover, if the arithmetic mean roughness Ra of the hard-coat layer 3 is 3 nm or more and 14 nm or less, excellent transparency of the hard-coat film 1 can be provided to the hard-coat film 1, while providing the outstanding anti blocking property to it. It can be secured.

When the material of the transparent base material 2 is COP, the transparent base material 2 is excellent in optical properties, while the mechanical strength is low (although it is easy to crack), but this hard coat film 1 has the above-mentioned hardness and pencil hardness Since it is provided with the hard-coat layer 3 which has the structure, the big fall (generation of a crack) of the mechanical strength of the hard-coat layer 3 in the hard-coat film 1 can be suppressed.

Variant

In each of the following modifications, the same members and processes as those in the above embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. Moreover, each modification can exhibit the effect similar to one Embodiment except having mentioned specially. Moreover, one Embodiment and a modification can be combined suitably.

In one embodiment shown in FIG. 1, the hard coat film 1 includes the hard coat layer 3 disposed only on one side of the transparent substrate 2. However, arrangement | positioning of the hard-coat layer 3 is not limited to the above, For example, although not shown, the hard-coat layer 3 arrange | positioned on both surfaces of the one side and the other side (two main surfaces) of the transparent base material 2 ) May be provided.

In one Embodiment shown in FIG. 2, the transparent conductive film 6 is the hard-coat layer 3, the optical adjustment layer 4, and the transparent conductive layer 5 arrange | positioned only at the thickness direction one side of the transparent base material 2 Although arrangement | positioning of the hard-coat layer 3, the optical adjustment layer 4, and the transparent conductive layer 5 is not limited to the above, For example, the thickness direction one side and the other side of the transparent base material 2 are provided. It may be provided with the hard-coat layer 3, the optical adjustment layer 4, and the transparent conductive layer 5 arrange | positioned in order, respectively at both sides of the.

Example

An Example and a comparative example are shown to the following, and this invention is demonstrated to it further more concretely. In addition, this invention is not limited to an Example and a comparative example at all. In addition, specific numerical values, such as a compounding ratio (ratio), a physical property value, and a parameter used in the following description, are the compounding ratios (ratio) corresponding to those described in said "mode for implementing an invention", It can be replaced by an upper limit (number defined as "less than", "less than") or a lower limit (number defined as "above" or "greater than") such as a physical property value or a parameter.

Example 1

As a transparent base material 2, the 100-micrometer-thick COP film (ZEONOR ZF-16, the Nippon Xeon company make) was prepared.

Then, the coating liquid (composition) prepared according to the prescription of Table 1 was apply | coated to one side of the transparent base material 2 using the wire bar # 6, and the solvent was then heated by heating at 80 degreeC for 1 minute. After removal, photocuring was carried out at an accumulated light amount of 230 mJ / cm 2 to form a hard coat layer 3. In addition, the detail of each component of Table 1 is described in Table 2.

Thereby, the hard coat film 1 provided with the transparent base material 2 and the hard-coat layer 3 was manufactured.

Example 2-Comparative Example 2

The hard-coat layer 3 was formed like Example 1 except having changed the coating liquid (composition) according to the prescription of Table 1.

<Evaluation>

The following items were evaluated, and as a result, it is shown in Table 3.

thickness

The thickness of the hard coat layer 3 was measured using MCPD2000 (manufactured by Otsuka Electronics Co., Ltd.).

Hardness

The hardness of the hard coat layer 3 was measured by the nanoindentation method.

In the nanoindentation method, nanoindenters (probes and indenters) are pressed into one side of the hard coat layer 3, and the displacement-load hysteresis curve obtained thereby is numerically processed by software (triboscan) of the measuring device unit. Indentation hardness was obtained.

Nanoindenter device and measurement conditions are as follows.

Nano indenter device: 「Tribo Indenter」, manufactured by Hysitron Inc.

Measuring method: single indentation

Indentation Speed: 60 μN / sec

Max pressure input: 300 μN

Maximum pressure input holding time: 2 seconds

Probe: Triangular pyramid (Verkhović)

Temperature: 23 ℃

Indentation Depth: 1/10 of the thickness of the hard coat layer 3

Pencil hardness

The pencil hardness of the hard coat layer 3 was measured according to JIS K5600-5-4 "scratch hardness (pencil method)" (1999).

Arithmetic Mean Roughness Ra

Arithmetic mean roughness Ra of the hard coat layer 3 was measured in accordance with JIS B 0601 (2013).

Anti blocking property

Another transparent base material (ZEONOR ZF-16, manufactured by Nippon Xeon Co., Ltd.) was pressed with pressure on the surface of the hard coat layer 3, and the adhesion (antiblocking property) to the hard coat layer 3 of the other transparent base material was as follows. Evaluation was as follows.

(Circle): The adhesion to the hard-coat layer 3 of another transparent base material did not arise.

(Triangle | delta): Although another transparent base material adheres once to the hard-coat layer 3, when 10 second passed, it fell off from the hard-coat layer 3.

X: The other transparent base material adhered with respect to the hard-coat layer 3, and even if it passed after 10 second, it did not fall from the hard-coat layer 3.

Haze

The haze of the hard coat film 1 (thickness 101 micrometers) was measured by the haze meter (HM-150, Murakami Color Research Institute).

Flex resistance

The flex resistance of the hard coat film 1 was evaluated by a 180 degree bending test. Evaluation criteria are as follows.

(Circle): Even if the hard-coat film 1 was bent 180 degrees, it was not broken.

X: When the hard-coat film 1 was bent 180 degrees, it was broken

Scratch resistance

The scratch resistance of the hard coat film 1 was evaluated by carrying out 10 reciprocating sliding friction of the thickness direction one surface of the hard coat film 1 with 100 g of steel wool. Evaluation criteria are as follows.

○: less than 10 scratches were observed.

×: 10 or more scratches were observed

In addition, although the said invention was provided as embodiment of an illustration of this invention, this is only a mere illustration and should not interpret it limitedly. Modifications of the present invention which are obvious to those skilled in the art are included in the later claims.

Claims (5)

The transparent base material and the hard-coat layer are provided in order in the thickness direction,
The hard coat layer contains a resin matrix and particles,
The hardness of the hard coat layer measured by the nanoindentation method is 0.320 kPa or more, 0.520 kPa or less,
The pencil hardness of the said hard-coat layer is B or less, The hard coat film characterized by the above-mentioned. The method of claim 1,
The thickness of the said hard-coat layer is 3 micrometers or less, The hard coat film characterized by the above-mentioned. The method of claim 1,
Arithmetic mean roughness Ra of the said hard-coat layer is 3 nm or more and 14 nm or less, The hard coat film characterized by the above-mentioned. The method of claim 1,
The material of the said transparent base material is a cycloolefin polymer, The hard coat film characterized by the above-mentioned. The hard coat film as described in any one of Claims 1-4, an optical adjustment layer, and a transparent conductive layer are provided in order in the thickness direction, The transparent conductive film characterized by the above-mentioned.

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