WO2014084008A1

WO2014084008A1 - Hard coat film and transparent conducting film

Info

Publication number: WO2014084008A1
Application number: PCT/JP2013/079968
Authority: WO
Inventors: 豊島裕; 前田清成; 土本達郎
Original assignee: 東レフィルム加工株式会社
Priority date: 2012-11-27
Filing date: 2013-11-06
Publication date: 2014-06-05
Also published as: JPWO2014084008A1; CN104822522B; KR101563564B1; CN104822522A; TWI608937B; JP5528645B1; KR20150048927A; TW201425035A

Abstract

Provided is a hard coat film characterized by the following: a first hard coat layer containing particles is provided on at least one surface of a base film; protrusions formed by the particles are present on the surface of the first hard coat layer at a density of 300-4000 per 100 μm²; the center line average roughness (Ra1) of the surface of the first hard coat layer is under 30 nm and the haze value is less than 1.5%. The hard coat film has high transparency, good slipperiness and anti-blocking properties.

Description

Hard coat film and transparent conductive film

The present invention relates to a hard coat film having high transparency and good slipperiness and blocking resistance, and more particularly to a hard coat film suitable for a transparent conductive film.

A hard coat film in which a hard coat layer is laminated on a base film is used as a surface film for a display or a touch panel, or as a base film for an electrode film for a touch panel (transparent conductive film for a touch panel). The hard coat film used for these uses is required to have high transparency and good slipping and blocking resistance.

It has been proposed to provide protrusions on the surface in order to improve the slipperiness and blocking resistance of the hard coat film or polyester film (Patent Documents 1 and 2).

JP-A-7-314628 Japanese Patent Laid-Open No. 2000-211082

However, the techniques disclosed in the above-mentioned patent documents have not yet fully satisfied transparency, slipperiness and blocking resistance.

Accordingly, an object of the present invention is to provide a hard coat film having high transparency and good slipping and blocking resistance in view of the above-mentioned problems of the prior art. Another object of the present invention is to provide a hard coat film suitable for a transparent conductive film.

The above object of the present invention is achieved by any one of the following configurations 1) to 15).

1) A first hard coat layer containing particles is provided on at least one surface of the base film, and protrusions made of the particles are present on the surface of the first hard coat layer at a density of 300 to 4000 per 100 μm ^2. A hard coat film having a center line average roughness (Ra1) of a surface of the first hard coat layer of less than 30 nm and a haze value of less than 1.5%.

2) The hard coat film according to 1), wherein the average particle diameter (r) of the particles is 0.05 to 0.5 μm.

3) The hard coat according to 1) or 2), wherein the ratio (r / d) of the average particle diameter (r) of the particles to the thickness (d) of the first hard coat layer is 0.01 to 0.30. the film.

4) The hard coat film according to any one of 1) to 3), wherein an average diameter of the protrusions is 0.03 to 0.3 μm, and an average height of the protrusions is 0.03 to 0.3 μm.

5) The hard coat film according to any one of 1) to 4), wherein an average interval between the protrusions is 0.10 to 0.70 μm.

6) The hard coat film according to any one of 1) to 5), wherein the thickness (d) of the first hard coat layer is 0.5 μm or more and less than 10 μm.

7) A resin layer is provided between the base film and the first hard coat layer, and the resin layer has a thickness of 0.005 to 0.3 μm and an average particle diameter of 1. The hard coat film according to any one of 1) to 6), which contains particles that are three times or more.

8) The base film is a polyethylene terephthalate film, and has a resin layer having a refractive index of 1.55 to 1.61 between the base film and the first hard coat layer. Hard coat film according to crab.

9) The hard coat film according to any one of 1) to 8), which has a resin layer having a wetting tension of 52 mN / m or less between the base film and the first hard coat layer.

10) The hard coat film according to 9), wherein the thickness of the first hard coat layer is less than 2 μm.

11) Among the group consisting of particles contained in the first hard coat layer are inorganic particles that have been subjected to a surface treatment for reducing the surface free energy of the particles, and inorganic particles that have been subjected to a hydrophobic treatment on the surface of the particles. The hard coat film according to any one of 1) to 10), which is at least one selected from the group consisting of:

12) The hard coat film according to 11), wherein the surface treatment for obtaining inorganic particles subjected to a surface treatment for reducing the surface free energy of the particles is the following (I) or (II).
(I) At least selected from the group consisting of an organosilane compound having a fluorine atom represented by the following general formula (1), a hydrolyzate of the organosilane, and a partial condensate of the hydrolyzate of the organosilane Surface treatment with one compound.
C _n F _{2n + 1} — (CH ₂ ) _m —Si (Q) ₃ ... General formula (1)
(In general formula (1), n represents an integer of 1 to 10, m represents an integer of 1 to 5. Q represents an alkoxy group having 1 to 5 carbon atoms or a halogen atom.)
(II) Treatment with a compound represented by the following general formula (2), and further surface treatment with a fluorine compound represented by the following general formula (3).
BR ⁴ —SiR ⁵ _n (OR ⁶ ) _3-n ... General formula (2)
DR ⁷ -Rf ² ... General formula (3)
(In the general formulas (2) and (3), B and D each independently represent a reactive site, and R ⁴ and R ⁷ are each independently derived from an alkylene group having 1 to 3 carbon atoms, or the alkylene group. R ⁵ and R ⁶ each independently represent hydrogen or an alkyl group having 1 to 4 carbon atoms, Rf ² represents a fluoroalkyl group, and n represents an integer of 0 to 2.)

13) The hydrophobic compound used in the hydrophobization treatment for obtaining inorganic particles having the surface of the particles hydrophobized is a fluorine compound having a fluoroalkyl group having 4 or more carbon atoms and a reactive site, carbon number 8 11) The long-chain hydrocarbon compound having the above hydrocarbon group and reactive site, and at least one compound selected from the group consisting of a silicone compound having a siloxane group and reactive site. Hard coat film.

14) The hard coat film according to any one of 1) to 13), wherein the particles contained in the first hard coat layer are silica particles.

15) A second hard coat layer is provided on the surface of the base film opposite to the surface on which the first hard coat layer is provided, and the surface of the second hard coat layer is substantially free of protrusions made of particles. The hard coat film according to any one of 1) to 14), wherein the center line average roughness (Ra2) of the surface of the second hard coat layer is 25 nm or less.

16) A transparent conductive film comprising a transparent conductive film on at least one surface of the hard coat film according to any one of 1) to 15) above.

According to the present invention, it is possible to provide a hard coat film having high transparency and good slipperiness and blocking resistance. The hard coat film of the present invention is suitable for a base film of a transparent conductive film.

FIG. 1 is an example of an observation view of the surface of the first hard coat layer observed with a scanning electron microscope. FIG. 2 is a diagram schematically showing the planar shape of the protrusions on the surface of the first hard coat layer. FIG. 3 is a schematic view schematically showing the surface of the first hard coat layer in FIG. FIG. 4 is a schematic diagram in which a part of FIG. 3 is omitted.

The hard coat film which concerns on one embodiment of this invention has a 1st hard coat layer in the at least one surface of a base film. The first hard coat layer contains particles, protrusions due to particles on the surface of the first hard coat layer (hereinafter, simply will be referred to as "projections") are perforated 300-4000 per 100 [mu] m ² of. The center line average roughness (Ra1) of the surface of the first hard coat layer is less than 30 nm. Such a hard coat film of this embodiment has a haze value of less than 1.5%.

By having 300 to 4000 protrusions per unit area (100 μm ² ) of the surface of the first hard coat layer on the surface of the first hard coat layer, the slipping property and the blocking resistance are improved.

The range of the number density of protrusions is preferably in the range of 400 to 3,500 per 100 μm ² , more preferably in the range of 500 to 3000, still more preferably in the range of 600 to 3000, and particularly preferably in the range of 700 to 2500.

When the number density of the particles is less than 300 per 100 μm ² , the slipperiness and blocking resistance are lowered. On the other hand, when the number density of particles exceeds 4000 per 100 μm ² , the smoothness of the surface of the first hard coat layer is lowered, the haze value is increased, and the transparency of the hard coat film is lowered.

The hard coat film of this embodiment has a relatively large number of protrusions on the surface of the first hard coat layer as described above, while the surface of the first hard coat layer is relatively smooth and the haze value of the hard coat film is small. This is one of the features. Specifically, it is important that the center line average roughness (Ra1) on the surface of the first hard coat layer in this embodiment is less than 30 nm, and the haze value of the hard coat film is less than 1.5%. .

The center line average roughness (Ra1) of the first hard coat layer surface is preferably 25 nm or less, more preferably 20 nm or less, and particularly preferably 18 nm or less. The lower limit center line average roughness (Ra1) is preferably 5 nm or more, more preferably 7 nm or more, and particularly preferably 9 nm or more from the viewpoint of ensuring slipperiness and blocking resistance.

When the center line average roughness (Ra1) on the surface of the first hard coat layer is 30 nm or more, the smoothness is lowered and the transparency of the hard coat film is lowered. That is, the haze value of the hard coat film is increased.

It is important that the hard coat film of the present embodiment has a haze value of less than 1.5% from the viewpoint of realizing high transparency. The haze value of the hard coat film of this embodiment is preferably 1.1% or less, more preferably 1.0% or less. The lower haze value is preferably as small as possible, but practically about 0.01%.

The surface of the first hard coat layer has 300 to 4000 protrusions per 100 μm ² , the center line average roughness (Ra1) of the first hard coat layer surface is less than 30 nm, and the haze value of the hard coat film is 1. In order to make it less than 5%, particles having an average particle diameter (r) of 0.05 to 0.5 μm are contained in the first hard coat layer, and these particles are relatively placed in the vicinity of the surface of the first hard coat layer. It is preferable that protrusions be formed on the surface of the first hard coat layer by making it exist in large quantities.

Further, the ratio (r / d) of the average particle diameter (r) (μm) of the particles contained in the first hard coat layer to the thickness (d) (μm) of the first hard coat layer is 0.01 to 0.00. 30 is preferable. Thereby, the center line average roughness (Ra1) on the surface of the first hard coat layer is reduced, and the haze value of the hard coat film is also reduced.

Hereinafter, each component constituting the hard coat film will be described in detail.

[Base film]
A plastic film is preferably used for the base film. Examples of the material constituting the base film include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyimide, polyphenylene sulfide, aramid, polypropylene, polyethylene, polylactic acid, polyvinyl chloride, polycarbonate, and polymethacrylic. Examples include methyl acid, alicyclic acrylic resin, cycloolefin resin, triacetyl cellulose, and those obtained by mixing and / or copolymerizing these resins. A film obtained by unstretching these resins, or uniaxially stretching or biaxially stretching into a film can be applied as a base film.

Among the substrate films described above, the polyester film is excellent in transparency, dimensional stability, mechanical properties, heat resistance, electrical properties, chemical resistance, and the like, and a polyethylene terephthalate film (PET film) is particularly preferably used. .

The range of the thickness of the base film is suitably 20 to 300 μm, preferably 30 to 200 μm, and more preferably 50 to 150 μm.

The base film preferably has at least a resin layer as shown below on the surface on which the first hard coat layer is laminated. That is, it is preferable to have the resin layer shown below between a base film and a 1st hard-coat layer.

[Resin layer]
In order to reinforce the adhesion between the base film and the first hard coat layer, the base film is preferably provided with a resin layer on at least the surface on which the first hard coat layer is laminated.

The resin layer is a layer containing a resin as a main component. Specifically, the resin layer is a layer containing 50% by mass or more of resin with respect to 100% by mass of the total solid content of the resin layer. Examples of the resin forming the resin layer include polyester resin, acrylic resin, urethane resin, polycarbonate resin, epoxy resin, alkyd resin, urea resin, and the like. These resins can be used alone or in combination.

The resin layer is interposed between the base film and the first hard coat layer, and from the viewpoint of improving the adhesion between the base film and the first hard coat layer, the resin is a polyester resin, an acrylic resin, and a polyurethane resin. It is preferable to contain at least one selected from the group consisting of In particular, the resin layer preferably contains at least a polyester resin as a resin.

The resin content in the resin layer is preferably 60% by mass or more, more preferably 70% by mass or more, and particularly preferably 80% by mass or more with respect to 100% by mass of the total solid content of the resin layer. Regarding the upper limit, the resin content in the resin layer is preferably 95% by mass or less, and more preferably 90% by mass or less.

Further, the resin layer may be formed in a two-layer configuration. In the case of a two-layer structure, it is preferable that a first resin layer mainly composed of a polyester resin and a second resin layer mainly composed of an acrylic resin are sequentially formed from the base film side. Details of the two-layer configuration will be described later.

The resin layer preferably contains particles from the viewpoint of ensuring appropriate slipping and winding properties in the manufacturing process of the hard coat film.

The particles contained in the resin layer are not particularly limited, but inorganic particles such as silica particles, titanium oxide, aluminum oxide, zirconium oxide, calcium carbonate, zeolite particles, acrylic particles, silicone particles, polyimide particles, Teflon (registered trademark) ) Organic particles such as particles, crosslinked polyester particles, crosslinked polystyrene particles, crosslinked polymer particles, and core-shell particles. Among these, silica particles are preferable, and colloidal silica is particularly preferable.

The particles contained in the resin layer preferably have an average particle size larger than the thickness of the resin layer. Specifically, the average particle diameter is preferably 1.3 times or more of the thickness of the resin layer, more preferably 1.5 times or more, and particularly preferably 2.0 times or more. The upper limit is preferably 20 times or less, more preferably 15 times or less, and particularly preferably 10 times or less.

The slip property and the blocking resistance are further improved by directly laminating the first hard coat layer on the resin layer containing particles having an average particle diameter larger than the thickness of the resin layer.

The average particle size of the particles contained in the resin layer is appropriately selected according to the thickness design of the resin layer. Specifically, the range of the average particle size is preferably in the range of 0.02 to 1 μm. A range of 0.05 to 0.7 μm is more preferable, and a range of 0.1 to 0.5 μm is particularly preferable. If the average particle size is less than 0.02 μm, the slipperiness and blocking resistance may be lowered. If the average particle diameter exceeds 1 μm, the particles may fall off, the transparency may be lowered, or the appearance may be deteriorated.

The thickness range of the resin layer is preferably in the range of 0.005 to 0.3 μm. When the thickness of the resin layer is less than 0.005 μm, the adhesion between the base film and the first hard coat layer is lowered. Moreover, when the thickness of the resin layer is larger than 0.3 μm, the blocking resistance after the first hard coat layer is laminated may be lowered. The thickness of the resin layer is further preferably 0.01 μm or more, more preferably 0.015 μm or more, and particularly preferably 0.02 μm or more. Regarding the upper limit, the thickness of the resin layer is preferably 0.25 μm or less, preferably 0.2 μm or less, particularly preferably 0.15 μm or less. When there are a plurality of resin layers, it is preferable that the total thickness of all the resin layers satisfies the above thickness condition.

The range of the content of the particles in the resin layer is preferably in the range of 0.05 to 10% by mass, more preferably in the range of 0.1 to 8% by mass, particularly 0% to 100% by mass of the total solid content of the resin layer. The range of 5 to 5% by mass is preferable. When the content of the particles in the resin layer is less than 0.05% by mass, good slipping property and blocking resistance may not be obtained. When the content of the particles exceeds 10% by mass, the transparency is lowered. Or the applicability of the first hard coat layer may deteriorate, or the adhesion between the base film and the first hard coat layer may be reduced.

The resin layer preferably further contains a crosslinking agent. The resin layer is preferably a thermosetting layer containing the above-described resin and a crosslinking agent. By using such a thermosetting layer as the resin layer, the adhesion between the base film and the first hard coat layer can be further improved. The conditions (heating temperature, time) for thermosetting the resin layer are not particularly limited, but the heating temperature is preferably 70 ° C or higher, more preferably 100 ° C or higher, particularly preferably 150 ° C or higher, and most preferably 200 ° C or higher. . Regarding the upper limit, the heating temperature is preferably 300 ° C. or lower. The range of the heating time is preferably 5 to 300 seconds, and more preferably 10 to 200 seconds.

Examples of the crosslinking agent include melamine crosslinking agent, oxazoline crosslinking agent, carbodiimide crosslinking agent, isocyanate crosslinking agent, aziridine crosslinking agent, epoxy crosslinking agent, methylolated or alkylolized urea crosslinking agent, acrylamide Examples thereof include system crosslinking agents, polyamide resins, amide epoxy compounds, various silane coupling agents, and various titanate coupling agents. Among these, laminic crosslinking agents, oxazoline crosslinking agents, carbodiimide crosslinking agents, isocyanate crosslinking agents, and aziridine crosslinking agents are preferable, and melamine crosslinking agents are particularly preferable.

Examples of the melamine-based crosslinking agent include imino group type methylated melamine resin, methylol group type melamine resin, methylol group type methylated melamine resin, and fully alkyl type methylated melamine resin. Among these, imino group type melamine resins and methylolated melamine resins are preferably used.

The range of the content of the crosslinking agent in the resin layer is preferably in the range of 0.5 to 40% by mass, more preferably in the range of 1 to 30% by mass, especially 2 to 2% with respect to 100% by mass of the total solid content of the resin layer. A range of 20% by weight is preferred.

The reflection color of the hard coat film obtained by laminating the first hard coat layer on the base film via the resin layer is preferably a neutral colorless hue. From this viewpoint, when a polyethylene terephthalate film (PET film) is used as the base film, the range of the refractive index of the resin layer is preferably 1.55 to 1.61, and more preferably 1.56 to 1.60. A range of 1.57 to 1.59 is more preferable.

The refractive index of a polyethylene terephthalate film (PET film) is generally about 1.62 to 1.70, and by adjusting the refractive index of the resin layer to the above range (1.55 to 1.61), The reflected color can be close to neutral and colorless. That is, the difference (np−nr) between the refractive index (np) of the PET film and the refractive index (nr) of the resin layer is preferably in the range of 0.02 to 0.1, preferably 0.03 to 0.00. The range of 09 is more preferable, and the range of 0.04 to 0.08 is particularly preferable.

In order to set the refractive index of the resin layer to 1.55 to 1.61, it is preferable to use a polyester resin containing a naphthalene ring in the molecule as the resin. A polyester resin containing a naphthalene ring can be synthesized, for example, by using a polyvalent carboxylic acid such as 1,4-naphthalenedicarboxylic acid or 2,6-naphthalenedicarboxylic acid as a copolymerization component.

The range of the content of the polyester resin containing a naphthalene ring in the molecule in the resin layer is preferably 5 to 70% by mass, more preferably 10 to 60% by mass with respect to 100% by mass of the total resin.

It is preferable that the resin layer is applied on the base film by a wet coating method, and is thermoset and laminated. Furthermore, it is preferable that the resin layer is applied by a wet coating method in the manufacturing process of the base film, which is applied by a so-called in-line coating method, and is thermally cured and laminated. Examples of the wet coating method include a reverse coating method, a spray coating method, a bar coating method, a gravure coating method, a rod coating method, and a die coating method.

As described above, a resin layer having a two-layer structure can be adopted. Such a two-layered resin layer is preferably formed by applying one coating solution once and causing self-phase separation in the drying process. That is, a coating liquid containing the main component (polyester resin) of the first resin layer and the main component (acrylic resin) of the second resin layer is applied, and self-phase separation of each component is utilized in the drying process. It is preferable to employ a method of forming the first resin layer and the second resin layer.

In carrying out this phase separation method, it is preferable to increase the surface energy difference between the main component (polyester resin) of the first resin layer and the main component (acrylic resin) of the second resin layer. That is, it is preferable to use a polyester resin having a high surface energy and an acrylic resin having a low surface energy. In particular, it is preferable to use a polyester resin having a sulfonic acid group in order to increase the surface energy of the polyester resin.

When the resin layer has a two-layer configuration, the thickness of the first resin layer is set from the viewpoint of enhancing the adhesion between the base film and the first hard coat layer and making the reflected color of the hard coat film close to neutral and colorless. It is preferable to be larger than the thickness of the two resin layers. The thickness of the first resin layer is preferably 1.5 times or more, more preferably 2.0 times or more, and particularly preferably 3.0 times or more the thickness of the second resin layer.

Specifically, the thickness range of the first resin layer is preferably 0.02 to 0.2 μm, more preferably 0.03 to 0.15 μm, and particularly preferably 0.05 to 0.12 μm. preferable. The thickness of the second resin layer is preferably in the range of 0.005 to 0.1 μm, more preferably in the range of 0.01 to 0.07 μm, and particularly preferably in the range of 0.01 to 0.05 μm.

The resin layer provided between the base film and the first hard coat layer preferably has a surface wetting tension of 52 mN / m or less. That is, in the present invention, it is preferable that the wetting tension on the surface of the resin layer to which the first hard coat layer is applied is 52 mN / m or less. By laminating the first hard coat layer directly on such a resin layer, it becomes easy to form protrusions due to particles on the surface of the first hard coat layer, and as a result, the slipping property and the blocking resistance are further improved. Here, the wetting tension is a physical property value defined in JIS-K-6768.

A mode in which a resin layer having a wetting tension of 52 mN / m or less is provided between the base film and the first hard coat layer is effective when the thickness of the first hard coat layer is relatively small. When the thickness of the first hard coat layer is reduced, the absolute amount of particles contained in the first hard coat layer is also reduced. However, by laminating the first hard coat layer on the resin layer having a wetting tension of 52 mN / m or less, the particles contained in the first hard coat layer are likely to be unevenly distributed near the surface. Can be formed. This aspect is effective when the thickness of the first hard coat layer is less than 2 μm, and is particularly effective when the thickness of the first hard coat layer is 1.7 μm or less.

From the above viewpoint, the wetting tension on the surface of the resin layer is preferably 50 mN / m or less. On the other hand, from the viewpoint of ensuring adhesion between the base film and the first hard coat layer, the lower limit of the wetting tension on the surface of the resin layer is preferably 35 mN / m or more, more preferably 37 mN / m or more, and 40 mN / m. The above is particularly preferable. If the wetting tension on the surface of the resin layer is less than 35 mN / m, the adhesion of the first hard coat layer may be lowered.

From the viewpoint of controlling the wetting tension on the surface of the resin layer to 52 mN / m or less and improving the adhesion between the base film and the first hard coat layer, the resin to be contained in the resin layer is a polyester resin or an acrylic resin. It is preferable to use at least one selected from the group consisting of polyurethane resins. Among these resins, it is preferable to use a polyester resin and / or an acrylic resin, and it is particularly preferable to use at least a polyester resin as the resin.

Also, the wetting tension on the surface of the resin layer can be controlled by adjusting the type and content of the crosslinking agent described above. For example, when the content of the crosslinking agent increases, the wetting tension on the surface of the resin layer tends to decrease. Conversely, when the content of the crosslinking agent decreases, the wetting tension on the surface of the resin layer tends to increase.

[First hard coat layer]
The first hard coat layer contains particles, and protrusions due to the particles are formed on the surface of the first hard coat layer. The number density of protrusions on the surface of the first hard coat layer is 300 to 4000 per unit area (100 μm ² ) of the surface of the first hard coat layer. Further, the range of the number density of the protrusions is preferably in the range of 400 to 3,500 per 100 μm ² , more preferably in the range of 500 to 3000, further preferably in the range of 600 to 3000, and particularly preferably in the range of 700 to 2500. .

The range of the average particle diameter (r) of the particles contained in the first hard coat layer is preferably in the range of 0.05 to 0.5 μm, more preferably in the range of 0.06 to 0.4 μm, particularly 0.07. A range of ˜0.3 μm is preferred.

When the average particle diameter (r) of the particles contained in the first hard coat layer is less than 0.05 μm, a sufficiently large protrusion is not formed on the surface of the first hard coat layer, and slipping and blocking resistance are prevented. May not be improved sufficiently. When the average particle diameter (r) exceeds 0.5 μm, the smoothness of the surface of the first hard coat layer is lowered, the center line average roughness (Ra1) is 30 nm or more, or the haze value of the hard coat film is 1. .5% or more may cause inconvenience such as a decrease in transparency.

It is preferable that the average particle diameter (r) of the particles contained in the first hard coat layer is sufficiently smaller than the thickness (d) of the first hard coat layer. That is, the ratio between the average particle diameter (r) of the particles and the thickness (d) of the first hard coat layer is preferably in the range of 0.01 to 0.30. It is preferable that a relatively large amount of such particles be present near the surface of the first hard coat layer to form a relatively large number of protrusions on the surface of the first hard coat layer as described above. This can improve slipperiness and blocking resistance without reducing the smoothness of the surface of the first hard coat layer.

The range of the ratio (r / d) of the average particle diameter (r) of the particles contained in the first hard coat layer to the thickness (d) of the first hard coat layer is further in the range of 0.01 to 0.20. The range of 0.01 to 0.15 is more preferable, the range of 0.02 to 0.10 is particularly preferable, and the range of 0.02 to 0.08 is most preferable.

The range of the average diameter of the protrusions formed on the surface of the first hard coat layer by the particles as described above is preferably in the range of 0.03 to 0.3 μm. Further, the range of the average diameter of the protrusions is preferably in the range of 0.04 to 0.25 μm, and more preferably in the range of 0.05 to 0.2 μm. Thereby, slipperiness and blocking resistance can be improved without reducing transparency.

The average height of the protrusions is preferably in the range of 0.03 to 0.3 μm. Further, the range of the average height of the protrusions is preferably in the range of 0.04 to 0.25 μm, and more preferably in the range of 0.05 to 0.2 μm. Thereby, slipperiness and blocking resistance can be improved without reducing transparency.

The shape of the protrusion formed on the surface of the first hard coat layer is not particularly limited, but preferably has a circular shape or a planar shape close to a circular shape. Here, the planar shape of the protrusion refers to the planar shape when the surface of the first hard coat layer is observed with a scanning electron microscope (SEM).

FIG. 1 is an example of a surface photograph of the first hard coat layer by a scanning electron microscope. Projections 11 made of particles are formed on the surface of the first hard coat layer.

FIG. 2 is a diagram schematically showing the planar shape of the protrusions on the surface of the first hard coat layer.

In the schematic diagram shown in FIG. 2, the planar shape of the protrusion means that the diameter (Lmin) of the protrusion 11 orthogonal to the line segment representing the maximum diameter (Lmax) of the protrusion 11 and the center Lc, and the maximum of the protrusion 11. It means that the ratio (Lmin / Lmax) to the diameter (Lmax) is 0.65 or more.

The ratio (Lmin / Lmax) is preferably 0.70 or more, more preferably 0.80 or more, and particularly preferably 0.85 or more. The upper limit is 1.0.

1 All the planar shapes of the protrusions in the surface photograph of FIG. 1 are circular or “near circular” as defined above.

In the present specification, the diameter of the protrusion means the maximum diameter (Lmax) shown in FIG. The average diameter of the protrusions can be obtained from a surface photograph of the first hard coat layer as shown in FIG. 1 using a scanning electron microscope.

In the present specification, the height of the protrusion means the length from the top of the protrusion to the surface of the first hard coat layer. The average height of the protrusions can be measured from a cross-sectional photograph taken with a transmission electron microscope (TEM) of the first hard coat layer.

The range of the average spacing of the protrusions on the surface of the first hard coat layer is preferably in the range of 0.10 to 0.70 μm, more preferably in the range of 0.15 to 0.50 μm, particularly 0.20 to 0.40 μm. A range is preferred. Thereby, slipperiness and blocking resistance can be improved without reducing transparency.

The average interval between the protrusions can be obtained from a surface photograph of the first hard coat layer by a scanning electron microscope. FIG. 3 is a diagram schematically showing a surface photograph of the first hard coat layer by a scanning electron microscope. A method for measuring the average interval between the protrusions will be described with reference to FIG.

First, a single straight line 20 is drawn in the horizontal direction, and a vertical straight line 30 orthogonal to the horizontal straight line 20 is drawn. Next, with respect to all the protrusions riding on the horizontal straight line 20 (that is, in contact with the straight line 20), the distance between the adjacent protrusions is measured. A similar operation is performed on the vertical straight line 30. The intervals (distances) of all the protrusions thus obtained are averaged.

The method for measuring the average interval between the protrusions will be described in detail with reference to FIG.

FIG. 4 is a diagram in which only the projections on the horizontal straight line 20 or the vertical straight line 30 in FIG. 3 are selected and edited. In FIG. 4, the number of protrusions riding on the horizontal straight line 20 is five as indicated by reference numerals 1 to 5. The interval between adjacent protrusions is, for example, the distance P between the protrusion 1 and the protrusion 2 adjacent to the protrusion 1. Similarly, by measuring the distance between the protrusion 2 and the protrusion 3, the distance between the protrusion 3 and the protrusion 4, and the distance between the protrusion 4 and the protrusion 5, the distance between adjacent protrusions for all particles on the horizontal straight line 20 is measured. Measure.

Similarly, for all the protrusions on the straight line 30 in the vertical direction, the interval between adjacent protrusions is measured.

The above operation is performed by changing the position of the straight line in the horizontal direction and the position of the straight line in the vertical direction three times, and the average of all the obtained protrusion intervals is taken as the average interval of the protrusions.

As shown in FIG. 1, each protrusion on the surface of the first hard coat layer is preferably formed by one particle. This makes it easy to adjust the center line average roughness (Ra1) of the first hard coat layer surface to less than 30 nm and to adjust the haze value of the hard coat film to less than 1.5%. If protrusions are formed in a state where a plurality of particles are aggregated, the center line average roughness (Ra1) on the surface of the first hard coat layer and the haze value of the hard coat film tend to increase, such being undesirable.

The range of the content of the particles in the first hard coat layer is preferably 2.5 to 17% by mass, more preferably 3 to 15% by mass with respect to 100% by mass of the total solid content of the first hard coat layer. The range of 4 to 12% by mass is particularly preferable.

As described above, particles having an average particle diameter (r) sufficiently smaller than the thickness (d) of the first hard coat layer are contained in the first hard coat layer, and the particles are in the vicinity of the surface of the first hard coat layer. It is preferable that a relatively large number of protrusions be formed on the surface of the first hard coat layer.

In order for the particles to be present in the vicinity of the surface of the first hard coat layer, it is necessary to move (float) the particles in the vicinity of the surface in the process of forming the first hard coat layer. This can be achieved, for example, by using particles that have been subjected to a surface treatment for reducing the surface free energy of the particles, or particles that have been subjected to a hydrophobic treatment for hydrophobizing the surface of the particles. As the particles to be subjected to these treatments, inorganic particles are preferable, and silica particles are particularly preferable.

As particles contained in the first hard coat layer, inorganic particles are preferably used. Inorganic particles are preferably inorganic particles containing an element selected from Si, Na, K, Ca, and Mg. More preferably, inorganic particles containing a compound selected from silica particles (SiO ₂ ), alkali metal fluorides (NaF, KF, etc.), and alkaline earth metal fluorides (CaF ₂ , MgF _2, etc.) can be mentioned, Silica particles are particularly preferable from the viewpoint of durability.

The surface treatment for reducing the surface free energy of the particles includes an organosilane compound having a fluorine atom represented by the following general formula (1), a hydrolyzate of the organosilane, and a hydrolysis of the organosilane. And a surface treatment with at least one compound selected from the group consisting of partial condensates.

C _n F _{2n + 1} — (CH ₂ ) _m —Si (Q) ₃
.... General formula (1)

(In the general formula (1), n represents an integer of 1 to 10, m represents an integer of 1 to 5. Q represents an alkoxy group having 1 to 5 carbon atoms or a halogen atom.)

Specific examples of the compound of the general formula (1) include the following compounds.
_{_{_{_{C 4 F 9 CH 2 CH 2}}}} Si (OCH 3) 3
C ₆ F ₁₃ CH ₂ CH ₂ Si (OCH ₃ ) ₃
_{_{_{_{C 8 F 17 CH 2 CH 2}}}} Si (OCH 3) 3
_{_{_{_{C 6 F 13 CH 2 CH 2}}}} CH 2 Si (OCH 3) 3
_{_{_{_{C 6 F 13 CH 2 CH 2}}}} CH 2 CH 2 Si (OCH 3) 3
_{_{_{_{C 6 F 13 CH 2 CH 2}}}} Si (OC 2 H 5) 3
_{_{_{_{C 8 F 17 CH 2 CH 2}}}} CH 2 Si (OC 2 H 5) 3
C ₆ F ₁₃ CH ₂ CH ₂ CH ₂ CH ₂ Si (OC ₂ H ₅ ) ₃
C ₆ F ₁₃ CH ₂ CH ₂ SiCl ₃
C ₆ F ₁₃ CH ₂ CH ₂ SiBr ₃
C ₆ F ₁₃ CH ₂ CH ₂ CH ₂ SiCl ₃
C ₆ F ₁₃ CH ₂ CH ₂ Si (OCH ₃ ) Cl ₂

Further, as another surface treatment for reducing the surface free energy of the inorganic particles, a method of treating with a compound represented by the following general formula (2) and further treating with a fluorine compound represented by the following general formula (3) Is mentioned.

BR ⁴ —SiR ⁵ _n (OR ⁶ ) _3-n
.... General formula (2)

DR ⁷ -Rf ²
.... General formula (3)

(In the general formulas (2) and (3), B and D each independently represent a reactive site, and R ⁴ and R ⁷ are each independently derived from an alkylene group having 1 to 3 carbon atoms, or the alkylene group. R ⁵ and R ⁶ each independently represent hydrogen or an alkyl group having 1 to 4 carbon atoms, Rf ² represents a fluoroalkyl group, and n represents an integer of 0 to 2.)

Examples of the reactive site represented by B and D include a vinyl group, an allyl group, an acryloyl group, a methacryloyl group, an acryloyloxy group, a methacryloyloxy group, an epoxy group, a carboxyl group, and a hydroxyl group.

Specific examples of the general formula (2) include acryloxyethyltrimethoxysilane, acryloxypropyltrimethoxysilane, acryloxybutyltrimethoxysilane, acryloxypentyltrimethoxysilane, acryloxyhexyltrimethoxysilane, acryloxyheptyltri Methoxysilane, methacryloxyethyltrimethoxysilane, methacryloxypropyltrimethoxysilane, methacryloxybutyltrimethoxysilane, methacryloxyhexyltrimethoxysilane, methacryloxyheptyltrimethoxysilane, methacryloxypropylmethyldimethoxysilane, methacryloxypropylmethyldimethoxy Examples include silane and compounds in which the methoxy group in these compounds is substituted with other alkoxyl groups or hydroxyl groups. It is.

Specific examples of the general formula (3) include 2,2,2-trifluoroethyl acrylate, 2,2,3,3,3-pentafluoropropyl acrylate, 2-perfluorobutylethyl acrylate, 3-perfluoro Butyl-2-hydroxypropyl acrylate, 2-perfluorohexylethyl acrylate, 3-perfluorohexyl-2-hydroxypropyl acrylate, perfluorooctylmethyl acrylate, 2-perfluorooctylethyl acrylate, 3-perfluorooctyl-2- Hydroxypropyl acrylate, 2-perfluorodecylethyl acrylate, 2-perfluoro-3-methylbutylethyl acrylate, 3-perfluoro-3-methoxybutyl-2-hydroxypropyl acrylate, 2-perf Oro-5-methylhexyl ethyl acrylate, 3-perfluoro-5-methylhexyl-2-hydroxypropyl acrylate, 2-perfluoro-7-methyloctyl-2-hydroxypropyl acrylate, tetrafluoropropyl acrylate, octafluoropentyl acrylate , Dodecafluoroheptyl acrylate, hexadecafluorononyl acrylate, hexafluorobutyl acrylate, 2,2,2-trifluoroethyl methacrylate, 2,2,3,3,3-pentafluoropropyl methacrylate, 2-perfluorobutylethyl methacrylate , 3-perfluorobutyl-2-hydroxypropyl methacrylate, perfluorooctylmethyl methacrylate, 2-perfluorooctylethyl methacrylate 3-perfluorooctyl-2-hydroxypropyl methacrylate, 2-perfluorodecylethyl methacrylate, 2-perfluoro-3-methylbutylethyl methacrylate, 3-perfluoro-3-methylbutyl-2-hydroxypropyl methacrylate, 2 -Perfluoro-5-methylhexylethyl methacrylate, 3-perfluoro-5-methylhexyl-2-hydroxypropyl methacrylate, 2-perfluoro-7-methyloctylethyl methacrylate, 3-perfluoro-7-methyloctylethyl methacrylate , Tetrafluoropropyl methacrylate, octafluoropentyl methacrylate, octafluoropentyl methacrylate, dodecafluoroheptyl methacrylate, hexadecafluorononi And methyl methacrylate, 1-trifluoromethyl trifluoroethyl methacrylate, hexafluorobutyl methacrylate and the like.

Examples of the hydrophobic compound for subjecting the particle surface to a hydrophobic treatment include compounds having a hydrophobic group and a reactive site in the molecule. The hydrophobic group of the hydrophobic compound is not particularly limited as long as it generally has a hydrophobic function, but specific examples of the hydrophobic group include, for example, a fluoroalkyl group having 4 or more carbon atoms, a hydrocarbon group having 8 or more carbon atoms, and Examples include at least one functional group selected from the group consisting of siloxane groups.

The reactive site is a site that chemically reacts with radicals generated by receiving energy such as light or heat. Specific examples include vinyl group, allyl group, acryloyl group, methacryloyl group, acryloyloxy group, It is more preferable to have a reactive site that undergoes a chemical reaction upon receiving energy such as light or heat, such as a methacryloyloxy group, an epoxy group, a carboxyl group, or a hydroxyl group.

That is, as a hydrophobic compound for subjecting the particle surface to a hydrophobization treatment, a compound having a fluoroalkyl group having 4 or more carbon atoms and a reactive site (fluorine compound), a hydrocarbon group having 8 or more carbon atoms and reactivity. It is preferable to use at least one selected from the group consisting of a compound having a moiety (long chain hydrocarbon compound) and a compound having a siloxane group and a reactive moiety (silicone compound).

The long-chain hydrocarbon compound represents a compound having a hydrocarbon group having 8 or more carbon atoms which is a hydrophobic group in the molecule and a reactive site. The hydrocarbon group having 8 or more carbon atoms preferably has 8 to 30 carbon atoms. The hydrocarbon group having 8 or more carbon atoms can be selected regardless of a linear structure, a branched structure, or an alicyclic structure. More preferably, a linear alkyl alcohol having 10 to 22 carbon atoms, an alkyl epoxide, an alkyl acrylate, an alkyl methacrylate, an alkyl carboxylate (including acid anhydrides and esters), etc. are used as the long-chain hydrocarbon compound. be able to.

Specific examples of the long-chain hydrocarbon compound include polyhydric alcohols such as octanol, hexanediol, heptanediol, octanediol, stearyl alcohol, octyl acrylate, octyl methacrylate, 2-hydroxyoctyl acrylate, 2-hydroxyoctyl methacrylate, etc. Acrylate (methacrylate), acrylic silane such as octyltrimethoxysilane, and the like.

Examples of the silicone compound include compounds having a siloxane group that is a hydrophobic group in the molecule and a reactive site. As the reactive site of the silicone compound, an acryloyloxy group or a methacryloyloxy group is preferably used.

As the siloxane group, a polysiloxane group represented by the following general formula (4) is preferably used.

-(Si (R ⁸ ) (R ⁹ ) -O) _m-
.... General formula (4)

(In the general formula (4), R ⁸ and R ⁹ are each independently an alkyl group having 1 to 6 carbon atoms, a phenyl group, a 3-acryloxy-2-hydroxypropyl-oxypropyl group, a 2-acryloxy-3-hydroxypropyl group. -Represents an oxypropyl group, a polyethylene glycol propyl ether group having a terminal acryloyloxy group or methacryloyloxy group, or a polyethylene glycol propyl ether group having a terminal hydroxy group, and m represents an integer of 10 to 200.)

Specific examples of the silicone compound having a polysiloxane group represented by the general formula (4) as a hydrophobic group include compounds having a dimethylsiloxane group represented by the following general formula (5) and a reactive site. . Specific examples of the silicone compound having a dimethylsiloxane group of the general formula (5) and a reactive site include X-22-164B, X-22-164C, X-22-5002, X-22-174D, X -22-167B (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.).

.... General formula (5)

(In the formula, R represents alkyl having 1 to 7 carbon atoms, k represents an integer of 0 or 1, and m represents an integer of 10 to 200.)

Another specific example of the silicone compound having a polysiloxane group represented by the general formula (4) as a hydrophobic group and a reactive site is 3-acryloxy-2-hydroxy represented by the general formula (6). Examples thereof include compounds having a propyl-oxypropyl group and a methyl group, and compounds having a 2-acryloxy-3-hydroxypropyl-oxypropyl group and a methyl group represented by the general formula (7).

.... General formula (6)

.... General formula (7)

(In the general formulas (6) and (7), R represents an alkyl having 1 to 7 carbon atoms, k represents an integer of 0 or 1, and m represents an integer of 10 to 200.)

Furthermore, another specific example of the silicone compound having a polysiloxane group represented by the general formula (4) and a reactive site as a hydrophobic group is an acryloyloxy group or methacryloyloxy at the terminal represented by the general formula (8). Examples thereof include a compound having a polyethylene glycol propyl ether group having a group and a methyl group, and a compound having a polyethylene glycol propyl ether group having a hydroxy group at the terminal and a methyl group, represented by the general formula (9).

.... General formula (8)

.... General formula (9)

(In the general formulas (8) and (9), R represents alkyl having 1 to 7 carbon atoms, k represents an integer of 0 or 1, x represents an integer of 1 to 10, and m represents 10 to 200. Represents an integer.)

The fluorine compound having a fluoroalkyl group having 4 or more carbon atoms and a reactive site will be described. Here, the fluoroalkyl group may have a linear structure or a branched structure. The fluoroalkyl group preferably has 4 to 8 carbon atoms. As such a fluorine compound, fluoroalkyl alcohol, fluoroalkyl epoxide, fluoroalkyl halide, fluoroalkyl acrylate, fluoroalkyl methacrylate, fluoroalkyl carboxylate (including acid anhydrides and esters), and the like can be used. Among these, fluoroalkyl acrylate and fluoroalkyl methacrylate are preferable. For example, a compound having a fluoroalkyl group having 4 or more carbon atoms can be used from the compounds exemplified in the general formula (3).

The number of fluoroalkyl groups in the fluorine compound is not necessarily one, and the fluorine compound may have a plurality of fluoroalkyl groups.

The first hard coat layer preferably has a high hardness in order to suppress the occurrence of scratches on the hard coat film surface, and the pencil hardness defined by JIS K5600-5-4 (1999) is H or more. Those are preferred. The upper limit of pencil hardness is about 9H.

The first hard coat layer preferably contains a thermosetting resin or an active energy ray curable resin as a resin, and particularly preferably contains an active energy ray curable resin. Here, the active energy ray-curable resin means a resin that is polymerized and cured by active energy rays such as ultraviolet rays and electron beams.

As a polymerizable compound for obtaining an active energy ray-curable resin, a compound (monomer or oligomer) having a polymerizable functional group such as acryloyl group, methacryloyl group, acryloyloxy group, methacryloyloxy group, vinyl group, and allyl group. Can be mentioned.

The first hard coat layer is formed by applying the active energy ray-curable composition containing the polymerizable compound by a wet coating method, drying it as necessary, and then irradiating the active energy ray to cure. It is preferable that

Examples of polymerizable compounds (monomers and oligomers) are shown below, but are not limited to these compounds. In the following description, the expression “... (Meth) acrylate” includes two compounds “... acrylate” and “... methacrylate”.

Examples of the monomer include methyl (meth) acrylate, lauryl (meth) acrylate, ethoxydiethylene glycol (meth) acrylate, methoxytriethylene glycol (meth) acrylate, phenoxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, isobornyl ( Monofunctional acrylates such as (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxy-3-phenoxy (meth) acrylate, neopentyl glycol di (meth) acrylate, 1, 6-hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythrito Rutetra (meth) acrylate, dipentaerythritol tri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tripentaerythritol tri (meth) acrylate Polyfunctional acrylate such as tripentaerythritol hexa (meth) triacrylate, trimethylolpropane (meth) acrylic acid benzoate, trimethylolpropane benzoate, glycerin di (meth) acrylate hexamethylene diisocyanate, pentaerythritol tri (meth) ) Urethane acrylates such as acrylate hexamethylene diisocyanate.

Among the monomers described above, polyfunctional monomers having 3 or more polymerizable functional groups in one molecule are preferably used.

Examples of the oligomer include polyester (meth) acrylate, polyurethane (meth) acrylate, epoxy (meth) acrylate, polyether (meth) acrylate, alkit (meth) acrylate, melamine (meth) acrylate, and silicone (meth) acrylate. be able to.

Among the above oligomers, polyfunctional urethane (meth) acrylate oligomers having 3 or more polymerizable functional groups in one molecule are preferably used. As such a polyfunctional urethane (meth) acrylate oligomer, a commercially available product can be used. For example, urethane acrylate AH series, urethane acrylate AT series, urethane acrylate AT series, urethane acrylate UA series manufactured by Kyoeisha Chemical Co., Ltd., UN-3320 series, UN-900 series manufactured by Negami Kogyo Co., Ltd. NK Oligo U series, Ebecryl 1290 series manufactured by Daicel UCB, and the like.

The content of the polymerizable compound in the active energy ray-curable composition is preferably 50% by mass or more and 55% by mass or more with respect to 100% by mass of the total solid content of the active energy ray-curable composition. More preferably, it is more preferably 60% by mass or more, and particularly preferably 70% by mass or more. The upper limit is preferably 97% by mass or less, and more preferably 95% by mass or less.

When ultraviolet rays are used as the active energy ray, the active energy ray curable composition preferably contains a photopolymerization initiator. Specific examples of the photopolymerization initiator include acetophenone, 2,2-diethoxyacetophenone, p-dimethylacetophenone, p-dimethylaminopropiophenone, benzophenone, 2-chlorobenzophenone, 4,4′-dichlorobenzophenone, 4,4′-bisdiethylaminobenzophenone, Michler's ketone, benzyl, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, methyl benzoylformate, p-isopropyl-α-hydroxyisobutylphenone, α-hydroxyisobutylphenone, 2, Carbonyl compounds such as 2-dimethoxy-2-phenylacetophenone and 1-hydroxycyclohexyl phenyl ketone, tetramethylthiuram monosulfide, teto Sulfur compounds such as lamethylthiuram disulfide, thioxanthone, 2-chlorothioxanthone, and 2-methylthioxanthone can be used. These photopolymerization initiators may be used alone or in combination of two or more.

In addition, photopolymerization initiators are generally commercially available and can be used. For example, Irgacure (registered trademark) 184, Irgacure 907, Irgacure 379, Irgacure 819, Irgacure 127, Irgacure 500, Irgacure 754, Irgacure 250, Irgacure 1800, Irgacure 1870, Irgacure OXEDA, ROCIA OXEDA, manufactured by Ciba Specialty Chemicals Co., Ltd. TPO, DAROCUR1173, etc., Speedcure MBB, Speedcure PBZ, Speedcure ITX, SpeedKet CTX, Speedcure EDB, Escure I ONE, Ecure I KIP150, YAC RE BMS, KAYACURE DMBI, and the like.

The range of the content of the photopolymerization initiator is suitably in the range of 0.1 to 10% by mass with respect to 100% by mass of the total solid content of the active energy ray-curable composition, and 0.5 to 8% by mass. The range of is preferable.

The active energy ray-curable composition can further contain various additives such as an antioxidant, an ultraviolet absorber, a leveling agent, a particle dispersant, an organic antistatic agent, a lubricant, a colorant, and a pigment. .

The active energy ray-curable composition contains particles for forming protrusions on the surface of the first hard coat layer. As such particles, particles that have been subjected to the above-described surface treatment or hydrophobic treatment are preferably used. The range of the content of particles in the active energy ray-curable composition is preferably 2.5 to 17% by mass with respect to 100% by mass of the total solid content of the active energy ray-curable composition, and preferably 3 to 15% by mass. Is more preferable, and a range of 4 to 12% by mass is particularly preferable.

The refractive index range of the first hard coat layer is preferably from 1.48 to 1.54, more preferably from 1.50 to 1.54. The active energy ray-curable composition described above is applied by a wet coating method, dried as necessary, and then irradiated with active energy rays to form a first hard coat layer, whereby the refractive index is reduced. A first hard coat layer in the range of 1.48 to 1.54 can be obtained.

The range of the thickness of the first hard coat layer is suitably from 0.5 μm to less than 10 μm, preferably from 0.8 μm to 7 μm, more preferably from 1 μm to 5 μm, particularly from 1 μm to 3 μm. The following is preferred.

When the thickness of the first hard coat layer is less than 0.5 μm, the hardness of the first hard coat layer is lowered and scratches are easily formed. On the other hand, when the thickness of the first hard coat layer is 10 μm or more, inconveniences such as slipperiness and blocking resistance may decrease, curl may increase, and transmittance may decrease.

[Hard coat film]
The hard coat film has a first hard coat layer on at least one surface of the base film. The hard coat film may have a first hard coat layer only on one side of the base film, or may have a first hard coat layer on both sides of the base film.

Further, as another preferred embodiment of the hard coat film, the first hard coat layer is provided on one side of the base film, and the first hard coat layer of the base film is provided on the other side of the base film (that is, Examples thereof include a hard coat film having a second hard coat layer (on the side opposite to the provided surface).

In addition, when the 2nd hard coat layer laminated | stacked on the other surface of a base film takes the completely same structure as the 1st hard coat layer laminated | stacked on one side of a base film (namely, base film) Even when the first hard coat layer is laminated on both sides of the first hard coat layer, it may be referred to as a second hard coat layer in order to distinguish it from the first hard coat layer on one side.

[Second hard coat layer]
Hereinafter, the 2nd hard-coat layer provided in the other surface of a base film is demonstrated.

The second hard coat layer preferably has a high hardness in order to suppress the occurrence of scratches on the hard coat film surface, and the pencil hardness defined by JIS K5600-5-4 (1999) is H or more. It is preferable and 2H or more is more preferable. The upper limit of pencil hardness is about 9H.

The surface of the second hard coat layer is preferably relatively smooth and clear. For example, the center line average roughness (Ra2) of the surface of the second hard coat layer is preferably 25 nm or less, more preferably 20 nm or less, and particularly preferably 15 nm or less. The lower limit is not particularly limited, but is practically about 1 nm.

Since the second hard coat layer has a center line average roughness (Ra2) of the second hard coat layer surface of 25 nm or less, the second hard coat layer substantially contains particles having an average particle diameter of more than 0.5 μm. It is preferable not to contain. Here, the fact that the second hard coat layer does not substantially contain particles having an average particle size larger than 0.5 μm means that the coating liquid for forming the second hard coat layer (for example, active energy ray-curable composition) Means that particles having an average particle size of more than 0.5 μm are not intentionally added to the product.

The surface of the second hard coat layer is preferably relatively smooth and clear. Accordingly, it is preferable that substantially no protrusions due to particles exist on the surface of the second hard coat layer. Here, the fact that there are substantially no protrusions due to particles on the surface of the second hard coat layer means that the number of protrusions per unit area (100 μm ² ) on the surface of the second hard coat layer is 100 or less. To do. Preferably, the number of protrusions per unit area (100 μm ² ) on the surface of the second hard coat layer is 50 or less, more preferably 30 or less, and particularly preferably 0.

The second hard coat layer can contain particles having an average particle size of 0.5 μm or less, but it is preferable to adjust the average particle size of the particles contained in the second hard coat layer from the above viewpoint.

When the particles are contained in the second hard coat layer, the average particle diameter of the particles is preferably 0.2 μm or less, and more preferably 0.1 μm or less. The range of the content of such particles is suitably in the range of 0.1 to 15% by mass with respect to 100% by mass of the total solid content of the second hard coat layer, and in the range of 0.5 to 10% by mass. More preferably, the range of 1 to 8% by mass is particularly preferable.

The second hard coat layer preferably contains a thermosetting resin or an active energy ray curable resin as the resin, and particularly preferably contains an active energy ray curable resin. Here, the active energy ray-curable resin means a resin that is polymerized and cured by active energy rays such as ultraviolet rays and electron beams.

As the polymerizable compound for obtaining the active energy ray-curable resin, the same compounds as those described in the first hard coat layer can be used.

As with the first hard coat layer, the second hard coat layer is coated with an active energy ray-curable composition containing a polymerizable compound by a wet coating method, dried as necessary, and then irradiated with active energy rays. It is preferably formed by curing.

The refractive index range of the second hard coat layer is preferably in the range of 1.48 to 1.54, more preferably in the range of 1.50 to 1.54. The second hard coat layer is formed by applying the active energy ray-curable composition described above by a wet coating method, drying it as necessary, and then irradiating and curing with an active energy ray, whereby the refractive index. Can be obtained in the range of 1.48 to 1.54.

The range of the thickness of the second hard coat layer is suitably from 0.5 μm to less than 10 μm, preferably from 0.8 μm to 7 μm, more preferably from 1 μm to 5 μm, particularly from 1 μm to 3 μm. The following is preferred.

When the thickness of the second hard coat layer is less than 0.5 μm, the hardness of the second hard coat layer is lowered and scratches are easily formed. On the other hand, when the thickness of the second hard coat layer is 10 μm or more, inconveniences such as slipperiness and blocking resistance decrease, curl increase, and transmittance may decrease.

In order to reinforce the adhesion between the base film and the second hard coat layer, it is preferable to interpose the aforementioned resin layer between the base film and the second hard coat layer.

[Transparent conductive film]
The hard coat film of this embodiment is suitable as a base film of a transparent conductive film. That is, the transparent conductive film using the hard coat film of this embodiment as a base film is obtained by laminating a transparent conductive film on at least one surface of the hard coat film of this embodiment.

The transparent conductive film may be laminated on only one side of the hard coat film, or may be laminated on both sides.

Some examples of the configuration of the transparent conductive film using the hard coat film of the present invention as a base film are exemplified below, but the present invention is not limited thereto.

i) First hard coat layer / resin layer / base film / resin layer / first hard coat layer / transparent conductive film

ii) Transparent conductive film / first hard coat layer / resin layer / base film / resin layer / first hard coat layer / transparent conductive film

iii) First hard coat layer / resin layer / base film / resin layer / second hard coat layer / transparent conductive film

iv) Transparent conductive film / first hard coat layer / resin layer / base film / resin layer / second hard coat layer

v) Transparent conductive film / first hard coat layer / resin layer / base film / resin layer / second hard coat layer / transparent conductive film

Among the above configuration examples, i) or iii) is preferable. In other words, from the viewpoint of ensuring the slipperiness and blocking resistance of the hard coat film in the lamination step and processing step of the transparent conductive film, the first hard coat layer should be exposed without being laminated. Is preferred.

Furthermore, it is preferable that the hard coat layer on the surface on which the transparent conductive film is laminated is relatively smooth and clear. Therefore, in the configuration example of iii), the center line average roughness (Ra2) of the surface of the second hard coat layer is preferably 25 nm or less, more preferably 20 nm or less, and particularly preferably 15 nm or less. As described above, since the surface of the hard coat layer (for example, the second hard coat layer) on which the transparent conductive film is laminated is relatively smooth and clear, the transparency of the transparent conductive film is improved, which is preferable.

[Transparent conductive film]
Examples of the material for forming the transparent conductive layer include tin oxide, indium oxide, antimony oxide, zinc oxide, ITO (indium tin oxide), metal oxide such as ATO (antimony tin oxide), and metal nanowires (for example, silver Nanowire) and carbon naotube. Among these, ITO is preferably used.

The thickness of the transparent conductive film is preferably 10 nm or more, more preferably 15 nm or more, and particularly preferably 20 nm or more, from the viewpoint of ensuring good conductivity with a surface resistance value of 10 ³ Ω / □ or less. Preferably there is. On the other hand, if the thickness of the transparent conductive film is too large, the color (coloring) may become inconvenient or the transparency may be lowered. Therefore, the upper limit of the thickness of the transparent conductive film is preferably 60 nm or less. 50 nm or less is more preferable, and 40 nm or less is particularly preferable.

The method for forming the transparent conductive film is not particularly limited, and a conventionally known method can be used. Specifically, a dry film forming method (vapor phase film forming method) such as a vacuum vapor deposition method, a sputtering method, an ion plating method, or a wet coating method can be used.

The transparent conductive film formed as described above may be patterned. The patterning can form various patterns depending on the application to which the transparent conductive film is applied. In addition, although a pattern part and a non-pattern part are formed by patterning of a transparent conductive film, as a shape of a pattern part, stripe shape, a lattice shape, etc. are mentioned, for example.

The patterning of the transparent conductive film is generally performed by etching. For example, a transparent conductive film is patterned by forming a patterned etching resist film on the transparent conductive film by a photolithography method, a laser exposure method, or a printing method and then performing an etching process. After the transparent conductive film is patterned, the etching resist film is peeled off with an alkaline aqueous solution.

A conventionally well-known thing is used as an etching liquid. For example, inorganic acids such as hydrogen chloride, hydrogen bromide, sulfuric acid, nitric acid and phosphoric acid, organic acids such as acetic acid, and mixtures thereof, and aqueous solutions thereof are used.

Examples of the alkaline aqueous solution used for stripping and removing the etching resist film include 1 to 5% by mass of a sodium hydroxide aqueous solution and a potassium hydroxide aqueous solution.

[Refractive index adjusting layer]
In the configuration example of the transparent conductive film, the transparent conductive film may be directly laminated on the first hard coat layer or the second hard coat layer. However, the transparent conductive film and the first hard coat layer or the second hard coat layer may be laminated. It is preferable to interpose a refractive index adjusting layer between the coat layer. Hereinafter, the refractive index adjustment layer will be described.

The refractive index adjusting layer may be composed of only one layer or may be a laminated structure of two or more layers. The refractive index adjustment layer has a function for adjusting the reflection color and transmission color of the transparent conductive film laminated thereon, or a so-called “bone appearance” in which the patterned portion of the patterned transparent conductive film is visually recognized. It is a layer having a function to suppress.

As the configuration of the refractive index adjustment layer, for example, a single layer configuration of a high refractive index layer having a refractive index (n1) of 1.60 to 1.80, and a low refractive index having a refractive index (n2) of 1.30 to 1.53. One layer structure of the refractive index layer, or a laminated structure of the high refractive index layer and the low refractive index layer (the low refractive index layer is disposed on the transparent conductive film side), and the like.

The range of the refractive index (n1) of the high refractive index layer is further preferably in the range of 1.63 to 1.78, and more preferably in the range of 1.65 to 1.75. The refractive index (n2) of the low refractive index layer is further preferably in the range of 1.30 to 1.50, more preferably in the range of 1.30 to 1.48, and particularly preferably in the range of 1.33 to 1.46. preferable.

The thickness of the refractive index adjusting layer (referring to the total thickness in the case of a multilayer structure) is preferably 200 nm or less, more preferably 150 nm or less, particularly preferably 120 nm or less, and most preferably 100 nm or less. The lower limit thickness is preferably 30 nm or more, more preferably 40 nm or more, particularly preferably 50 nm or more, and most preferably 60 nm or more.

When the transparent conductive film is patterned, the refractive index adjusting layer is preferably a laminated structure of a high refractive index layer and a low refractive index layer from the viewpoint of suppressing “bone appearance”. In this case, it is preferable that the sum (nm) of the optical thickness of the high refractive index layer and the optical thickness of the low refractive index layer satisfies (1/4) λ (nm). Here, the optical thickness (nm) is the product of the refractive index and the actual layer thickness (nm), and λ is 380 to 780 (nm) which is the wavelength range of the visible light region.

In this specification, when the total of the optical thickness (nm) of the high refractive index layer and the optical thickness (nm) of the low refractive index layer satisfies (1/4) λ (nm), the following formula 1 is satisfied. That is. In the formula, n1 represents the refractive index of the high refractive index layer, d1 represents the thickness (nm) of the high refractive index layer, n2 represents the refractive index of the low refractive index layer, and d2 represents the thickness (nm) of the low refractive index layer. .

(380 nm / 4) ≦ (n1 × d1) + (n2 × d2) ≦ (780 nm / 4)
95 nm ≦ (n1 × d1) + (n2 × d2) ≦ 195 nm (Formula 1)

That is, the total of the optical thickness (n1 × d1) of the high refractive index layer and the optical thickness (n2 × d2) of the low refractive index layer is preferably 95 nm or more and 195 nm or less.

Furthermore, the total range of the optical thickness of the high refractive index layer and the optical thickness of the low refractive index layer is more preferably 95 to 163 nm, particularly preferably 95 to 150 nm, and most preferably 100 to 140 nm.

For the high refractive index layer, for example, an active energy ray-curable composition containing metal oxide fine particles having a refractive index of 1.65 or more is applied by a wet coating method, dried as necessary, and then irradiated with active energy rays. Then, it can be formed by curing. Here, the active energy ray-curable composition is a composition containing the polymerizable compound and the photopolymerization initiator described in the first hard coat layer.

Examples of the metal oxide fine particles include metal oxide particles such as titanium, zirconium, zinc, tin, antimony, cerium, iron, and indium. Specific examples of the metal oxide fine particles include, for example, titanium oxide, zirconium oxide, zinc oxide, tin oxide, antimony oxide, cerium oxide, iron oxide, zinc antimonate, tin oxide-doped indium oxide (ITO), and antimony-doped tin oxide. (ATO), phosphorus-doped tin oxide, aluminum-doped zinc oxide, gallium-doped zinc oxide, fluorine-doped tin oxide, and the like. These metal oxide fine particles may be used alone or in combination. Among the metal oxide fine particles, titanium oxide and zirconium oxide are particularly preferable because they can increase the refractive index without reducing transparency.

The content of the metal oxide fine particles in the active energy ray-curable composition is preferably 30% by mass or more, more preferably 40% by mass or more, with respect to 100% by mass of the total solid content of the active energy ray-curable composition. A mass% or more is particularly preferred. The upper limit is preferably 70% by mass or less, and preferably 60% by mass or less.

The low refractive index layer is, for example, coated with an active energy ray-curable composition containing low refractive index inorganic particles and / or a fluorine-containing compound as a low refractive index material by a wet coating method and, if necessary, dried. It can be formed by irradiating with active energy rays and curing. Here, the active energy ray-curable composition is a composition containing the polymerizable compound and the photopolymerization initiator described in the first hard coat layer.

As the low refractive index inorganic particles, inorganic particles such as silica and magnesium fluoride are preferable. Further, these inorganic particles are preferably hollow or porous. The content of such low refractive index inorganic particles is preferably 10% by mass or more, more preferably 20% by mass or more, and particularly preferably 30% by mass or more with respect to 100% by mass of the total solid content of the active energy ray-curable composition. Is preferred. The upper limit is preferably 70% by mass or less, preferably 60% by mass or less, and particularly preferably 50% by mass or less.

Examples of the fluorine-containing compound include fluorine-containing monomers, fluorine-containing oligomers, and fluorine-containing polymer compounds. Here, the fluorine-containing monomer or fluorine-containing oligomer is a monomer or oligomer having in the molecule thereof the aforementioned polymerizable functional group (functional group containing a carbon-carbon double bond group) and a fluorine atom.

Examples of fluorine-containing monomers and fluorine-containing oligomers include 2,2,2-trifluoroethyl (meth) acrylate, 2,2,3,3,3-pentafluoropropyl (meth) acrylate, and 2- (perfluorobutyl). ) Ethyl (meth) acrylate, 2- (perfluorohexyl) ethyl (meth) acrylate, 2- (perfluorooctyl) ethyl (meth) acrylate, 2- (perfluorodecyl) ethyl (meth) acrylate, β- (per Fluorine-containing (meth) acrylic acid esters such as fluorooctyl) ethyl (meth) acrylate, di- (α-fluoroacrylic acid) -2,2,2-trifluoroethylethylene glycol, di- (α-fluoroacrylic acid) ) -2,2,3,3,3-pentafluoropropylethylene glycol, -(Α-fluoroacrylic acid) -2,2,3,3,4,4,4-heptafluorobutylethylene glycol, di- (α-fluoroacrylic acid) -2,2,3,3,4,4 , 5,5,5-nonafluoropentylethylene glycol, di- (α-fluoroacrylic acid) -2,2,3,3,4,4,5,5,6,6,6-undecafluorohexylethylene Glycol, di- (α-fluoroacrylic acid) -2,2,3,3,4,4,5,5,6,6,7,7,7-tridecafluoroheptylethylene glycol, di- (α- Fluoroacrylic acid) -2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-pentadecafluorooctylethylene glycol, di- (α-fluoroacrylic acid) ) -3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, , 8-tridecafluorooctylethylene glycol, di- (α-fluoroacrylic acid) -2,2,3,3,4,4,5,5,6,6,7,7,8,8,9, And di- (α-fluoroacrylic acid) fluoroalkyl esters such as 9,9-heptadecafluorononylethylene glycol.

Examples of the fluorine-containing polymer compound include a fluorine-containing copolymer having a fluorine-containing monomer and a monomer for imparting a crosslinkable group as structural units. Specific examples of the fluorine-containing monomer unit include, for example, fluoroolefins (for example, fluoroethylene, vinylidene fluoride, tetrafluoroethylene, hexafluoroethylene, hexafluoropropylene, perfluoro-2,2-dimethyl-1,3-dioxole, etc. ), (Meth) acrylic acid partial or fully fluorinated alkyl ester derivatives (for example, Biscoat 6FM (manufactured by Osaka Organic Chemical), M-2020 (manufactured by Daikin), etc.), fully or partially fluorinated vinyl ethers, and the like. As a monomer for imparting a crosslinkable group, in addition to a (meth) acrylate monomer having a crosslinkable functional group in the molecule in advance such as glycidyl methacrylate, it has a carboxyl group, a hydroxyl group, an amino group, a sulfonic acid group, etc. ) Acrylate monomers (for example, (meth) acrylic acid, methylol (meth) acrylate, hydroxyalkyl (meth) acrylate, allyl acrylate, etc.).

The content of the fluorine-containing compound is preferably 30% by mass or more, more preferably 40% by mass or more, and particularly preferably 50% by mass or more with respect to 100% by mass of the total solid content of the active energy ray-curable composition. The upper limit is preferably 95% by mass or less, more preferably 90% by mass or less, and particularly preferably 80% by mass or less.

Of the fluorine-containing compounds, fluorine-containing monomers and fluorine-containing oligomers are preferably used. Since the fluorine-containing monomer and the fluorine-containing oligomer have a polymerizable functional group in the molecule, they contribute to the formation of a dense cross-linked structure of the low refractive index layer and can have a low refractive index.

[Touch panel]
The transparent conductive film which uses the hard coat film of this embodiment as a base film is preferably used as one of the constituent members of the touch panel.

The resistive touch panel usually has a configuration in which an upper electrode and a lower electrode are arranged via a spacer. However, the transparent conductive film using the hard coat film of this embodiment as a base film has an upper electrode and a lower electrode. It can be used for either one or both of the electrodes.

In addition, the capacitive touch panel is usually composed of patterned X electrodes and Y electrodes, but the transparent conductive film using the hard coat film of this embodiment as a base film is composed of X electrodes and Y electrodes. It can be used for either one or both.

The transparent conductive film used for the touch panel is required to have good transparency and workability (sliding property and blocking resistance), but the transparent conductive film using the hard coat film of this embodiment as a base film. Can sufficiently satisfy the above characteristics.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. In addition, the measuring method and evaluation method in a present Example are shown below.

(1) Refractive index measurement of each layer About a coating film (dry thickness of about 2 μm) formed by coating each coating solution on a silicon wafer with a spin coater, a phase difference measuring device (Nikon ( The refractive index of 589 nm was measured by NPDM-1000).

The refractive index of the substrate film (PET film) was measured at 589 nm using an Abbe refractometer according to JIS K7105 (1981).

(2) the cross section of the measurement resin layer base film laminated in the thickness of the resin layer was cut into ultra thin sections, RuO ₄ staining, OsO ₄ staining, or staining with double staining of both the ultramicrotomy, TEM The cross-sectional structure is observed under the following conditions with a transmission electron microscope, and the thickness of the resin layer is measured from the cross-sectional photograph. The measurement location is a portion where no particles exist. In addition, five places were measured and the average value was made into the thickness of the resin layer.

・ Measurement device: Transmission electron microscope (H-7100FA type, manufactured by Hitachi, Ltd.)
・ Measurement conditions: Acceleration voltage 100kV
・ Sample preparation: Freezing ultrathin section method ・ Magnification: 300,000 times

(3) Measurement of the thickness of the first and second hard coat layers, the high refractive index layer, and the low refractive index layer A cross section of the hard coat film was cut into ultra-thin sections, and an acceleration voltage of 100 kV with a TEM (transmission electron microscope). Observe (observe at a magnification of 1 to 300,000 times) and measure the thickness from the cross-sectional photograph. In addition, about the layer which has a processus | protrusion on the surface like a 1st hard-coat layer, it is the thickness in the part in which a processus | protrusion does not exist. The thickness was measured at five locations, and the average value was taken as the thickness.

(4) Measurement of average particle diameter of particles contained in first hard coat layer The cross section of the first hard coat layer was observed with a TEM (transmission electron microscope) (approximately 10,000 to 100,000 times), and the cross-sectional photograph thereof Thus, the maximum length of each of 30 randomly selected particles was measured, and the average value of these was taken as the average particle size.

(5) Measurement of average particle diameter of particles contained in resin layer The surface of the resin layer laminated on the base film was observed at a magnification of 10,000 times using an SEM (scanning electron microscope), and an image of particles ( The light intensity produced by the particles is connected to an image analyzer (for example, QTM900 manufactured by Cambridge Instrument), data is acquired by changing the observation location, and when the total number of particles reaches 5000 or more, the following numerical processing is performed, thereby obtaining The number average diameter d was defined as the average particle diameter (diameter).

D = Σdi / N

Where di is the equivalent circular diameter of the particle (the diameter of a circle having the same area as the cross-sectional area of the particle), and N is the number.

(6) Measurement of centerline average roughness (Ra1, Ra2) of the surface of the first and second hard coat layers Based on JIS B0601 (1982), stylus type surface roughness measuring instrument SE-3400 (Kosaka Co., Ltd.) Measured using a laboratory.

<Measurement conditions>
Feeding speed: 0.5mm / s
Evaluation length: 8mm
Cut-off value λc; 0.08mm

(7) Measurement of the number of protrusions on the surface of the first hard coat layer A cut sample (20 cm × 15 cm) of the hard coat film is prepared, and the surface of the first hard coat layer of the cut sample is measured with an SEM (scanning electron microscope). Photograph five points (approximately 10,000 to 100,000 times) and make five images (surface photographs). Next, for each of the five images, the number of protrusions existing in the range of 1 μm square (area 1 μm ² ) or 2 μm square (area 4 μm ² ) of the image was measured, converted into the number per 100 μm ² area, and averaged. . The area for measuring the number of protrusions is appropriately changed according to the photographing magnification.

(8) Measurement of the average diameter of the protrusions on the surface of the first hard coat layer The surface of the first hard coat layer of the hard coat film was photographed with an SEM (scanning electron microscope) (approximately 10,000 to 100,000 times) and imaged Create a (surface photo). Next, the diameter (maximum length) of 30 protrusions randomly selected from the image was measured and averaged.

(9) Measurement of average height of protrusions on the surface of the first hard coat layer A cut sample (20 cm × 15 cm) of a hard coat film is prepared, and a cross section of the first hard coat layer of this cut sample is taken with an SEM (scanning electron microscope). ) At 5 locations (approximately 10,000 to 100,000 times) to produce 5 cross-sectional photographs. Next, the heights of all the protrusions present in the five cross-sectional photographs were measured and averaged.

(10) Average spacing of protrusions The surface of the first hard coat layer of the hard coat film is photographed (approximately 10,000 to 100,000 times) with an SEM (scanning electron microscope) to produce an image (surface photograph). One straight line perpendicular to the horizontal and vertical directions is drawn on this image. Next, with respect to all the protrusions riding on (in contact with) the straight line in the horizontal direction, the distance from the adjacent protrusion is measured. The same operation is performed for one vertical straight line. This operation is performed by changing the position of the straight line in the horizontal direction and the position of the straight line in the vertical direction three times, and averages all the obtained protrusion intervals.

(11) Measurement of hard coat film Based on JIS K 7136 (2000), it was measured using a turbidimeter “NDH-2000” manufactured by Nippon Denshoku Industries Co., Ltd. In measurement, the hard coat film is arranged so that light is incident on the surface of the opposite surface of the first hard coat layer (that is, the surface on which the second hard coat layer is provided).

(12) Total light transmittance of hard coat film Based on JIS-K7361 (1997), it was measured using a turbidimeter NDH2000 (manufactured by Nippon Denshoku Industries Co., Ltd.).

(13) Visual evaluation of reflection color of hard coat film A black adhesive tape (Nitto Denko “Vinyl Tape No. 21 Tokuhaba Black”) was applied to the surface of the second hard coat layer of the hard coat film, and the first hard coat layer The reflection color of this surface was visually observed under a darkroom three-wavelength fluorescent lamp, and the following criteria were used.

Similarly, a black adhesive tape (Nitto Denko “Vinyl Tape No. 21 Tokuhaba Black”) is applied to the surface of the first hard coat layer of the hard coat film, and the reflection color of the second hard coat layer surface is set to three wavelengths in the dark room. It observed visually under the fluorescent lamp and performed on the following references | standards.
A: The reflection color is neutral and almost colorless.
C: The reflected color is colored.

(14) Evaluation of slipperiness The hard coat film was cut to produce two sheet pieces (20 cm × 15 cm). Place the two sheet pieces slightly on top of each other so that the first hard coat layer surface and the second hard coat layer surface of the two sheet pieces face each other, and place them on a smooth table. The quality of the slipperiness was determined by a method of fixing the upper sheet piece with a finger and sliding the upper sheet piece by hand. The measurement environment is 23 ° C. and 55% RH.
A: The slipperiness of the upper sheet piece is good.
B: The slipperiness of the upper sheet piece is inferior but relatively good.
C: The upper sheet piece does not slip.

(15) Evaluation of blocking resistance The hard coat film is cut to produce two sheet pieces (20 cm × 15 cm). The two sheets are superposed such that the first hard coat layer surface and the second hard coat layer surface face each other. Next, a sample in which two sheet pieces are overlapped is sandwiched between glass plates, and a weight of about 3 kg is placed thereon and left in an atmosphere of 50 ° C. and 90% (RH) for 48 hours. Next, the overlapping surface was visually observed to confirm the occurrence of Newton rings, and then both were peeled off and evaluated according to the following criteria.

A: Newton rings are not generated before peeling, and light peeling is performed without making a peeling sound at the time of peeling.
B: Some Newton rings are generated before peeling, and peeling is performed while making a small peeling sound during peeling.
C: Newton rings are generated on the entire surface before peeling, and are peeled off with a loud peeling sound during peeling.

(16) Pencil hardness of the first and second hard coat layers The surface of the first hard coat layer and the surface of the first hard coat layer of the hard coat film are based on JIS K5600-5-4 (1999), respectively. It was measured. The load is 750 g, and the speed is 30 mm / min. As the measuring device, a surface hardness tester (HEIDON; type 14DR) manufactured by Shinto Kagaku Co., Ltd. was used. The environment at the time of measurement is 23 ° C. ± 2 ° C. and relative humidity 55% ± 5%.

(17) Visibility of transparent conductive film pattern A sample was placed on a black plate, and whether or not the pattern portion of the transparent conductive film could be visually confirmed was evaluated according to the following criteria.

A: A pattern part cannot be visually recognized.
C: A pattern part can be visually recognized.

(18) Measurement of the wetting tension of the resin layer The base film on which the resin layer was laminated was seasoned for 6 hours in an ordinary atmosphere (23 ° C., relative humidity 50%), and JIS-K-6768 ( 1999).

<Resin layer forming coating solution>
(Resin layer forming coating solution a)
In terms of solid content, Tg (glass transition temperature) of 120 ° C. is 26% by mass of polyester resin a, Tg is 80 ° C. of polyester resin b is 54% by mass, melamine-based crosslinking agent is 18% by mass, and particles are 2% by mass. % Was mixed to prepare an aqueous dispersion coating solution.

Polyester resin a; polyester resin obtained by copolymerizing 43 mol% of 2,6-naphthalenedicarboxylic acid, 7 mol% of 5-sodium sulfoisophthalic acid, and 50 mol% of a diol component containing ethylene glycol; polyester resin b; Polyester resin and melamine-based crosslinking agent obtained by copolymerization of 38 mol% terephthalic acid, 12 mol% trimellitic acid, and 50 mol% diol component containing ethylene glycol; "Nikarac MW12LF" manufactured by Sanwa Chemical Co., Ltd.
・ Particles: colloidal silica with an average particle size of 0.19 μm

(Resin layer forming coating solution b)
An aqueous dispersion coating solution was prepared by mixing 80% by mass of the following acrylic resin, 18% by mass of the melamine-based crosslinking agent, and 2% by mass of the particles in a solid content mass ratio.

・ Acrylic resin (acrylic resin consisting of the following copolymer composition)
Methyl methacrylate 63% by weight
Ethyl acrylate 35% by weight
Acrylic acid 1% by weight
N-methylolacrylamide 1% by weight
・ Melamine-based cross-linking agent; “Nicarac MW12LF” manufactured by Sanwa Chemical Co., Ltd.
・ Particles: colloidal silica with an average particle size of 0.19 μm

<Surface treatment silica particle dispersion>
(Surface treatment silica particle dispersion A)
150 parts by mass of colloidal silica (“organosilica sol IPA-ST-ZL” manufactured by Nissan Chemical Industries, Ltd.) is mixed with 13.7 parts by mass of methacryloxypropyltrimethoxysilane and 1.7 parts by mass of a 10% by mass formic acid aqueous solution. , And stirred at 70 ° C. for 1 hour. Then, after adding 13.8 parts by mass of a fluorine compound (H ₂ C═CH—COO—CH ₂ — (CF ₂ ) ₈ F) and 0.57 parts by mass of 2,2-azobisisobutyronitrile, A dispersion was obtained by heating and stirring at 90 ° C. for minutes.

(Surface treatment silica particle dispersion B)
150 parts by mass of colloidal silica (“organosilica sol IPA-ST-ZL” manufactured by Nissan Chemical Industries, Ltd.) is mixed with 13.7 parts by mass of methacryloxypropyltrimethoxysilane and 1.7 parts by mass of a 10% by mass formic acid aqueous solution. , And stirred at 70 ° C. for 1 hour. Next, 9 parts by mass of a fluorine compound (H ₂ C═CH—COO—CH ₂ — (CF ₂ ) ₈ F) as a hydrophobic compound and a silicone compound (“PC-4131” manufactured by Dainippon Ink & Chemicals, Inc.) 4.8 parts by mass and 0.57 parts by mass of 2,2-azobisisobutyronitrile were added, followed by heating and stirring at 90 ° C. for 60 minutes to obtain a dispersion.

(Surface treatment silica particle dispersion C)
Colloidal silica (“organosilica sol IPA-ST-ZL” manufactured by Nissan Chemical Industries, Ltd.) 330 parts by mass, acryloyloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) 8 parts by mass, tridecafluorooctyltrimethoxy After adding 2 parts by mass of silane (manufactured by GE Toshiba Silicone Co., Ltd.) and 1.5 parts by mass of diisopropoxyaluminum ethyl acetate, 9 masses of ion-exchanged water was added. After making it react at 60 degreeC for 8 hours, it cooled to room temperature and added 1.8 mass parts of acetylacetone. Next, while adding cyclohexanone to this dispersion, solvent displacement was performed by distillation under reduced pressure at a pressure of 20 kPa to obtain a dispersion.

(Surface treatment silica particle dispersion D)
150 parts by mass of colloidal silica (“organosilica sol MEK-ST-2040” manufactured by Nissan Chemical Industries, Ltd.) was mixed with 13.7 parts by mass of methacryloxypropyltrimethoxysilane and 1.7 parts by mass of 10% by mass formic acid aqueous solution. , And stirred at 70 ° C. for 1 hour. Then, after adding 13.8 parts by mass of a fluorine compound (H ₂ C═CH—COO—CH ₂ — (CF ₂ ) ₈ F) and 0.57 parts by mass of 2,2-azobisisobutyronitrile, A dispersion was obtained by heating and stirring at 90 ° C. for minutes.

(Surface treatment silica particle dispersion E)
150 parts by mass of colloidal silica (“organosilica sol MEK-ST-L” manufactured by Nissan Chemical Industries, Ltd.) is mixed with 13.7 parts by mass of methacryloxypropyltrimethoxysilane and 1.7 parts by mass of a 10% by mass formic acid aqueous solution. , And stirred at 70 ° C. for 1 hour. Then, after adding 13.8 parts by mass of a fluorine compound (H ₂ C═CH—COO—CH ₂ — (CF ₂ ) ₈ F) and 0.57 parts by mass of 2,2-azobisisobutyronitrile, A dispersion was obtained by heating and stirring at 90 ° C. for minutes.

[Example 1]
A hard coat film was prepared in the following manner.

<Production of resin layer laminated PET film>
A resin layer was in-line coated on both sides of a polyethylene terephthalate film (PET film) having a refractive index of 1.65 and a thickness of 100 μm within the PET film manufacturing process. That is, the coating liquid a for forming a resin layer is applied to both surfaces of a PET film uniaxially stretched in the longitudinal direction by a bar coating method, dried at 100 ° C., then biaxially stretched in the width direction, and heated at 230 ° C. for 20 seconds. The PET film in which the resin layer was laminated | stacked on both surfaces was processed and heat-cured. Each of the resin layers laminated on both sides of the PET film had a refractive index of 1.59 and a thickness of 0.09 μm.

<Lamination of first and second hard coat layers>
The following active energy ray-curable composition a is applied by a gravure coating method on a resin layer on one side of a PET film having a resin layer laminated on both sides, dried at 90 ° C., and then irradiated with ultraviolet rays 400 mJ / cm ² . And cured to form a first hard coat layer. The first hard coat layer had a thickness of 2.6 μm and a refractive index of 1.51.

Next, the second hard coat is applied to the resin layer on the other side of the PET film (the side opposite to the side on which the first hard coat layer is laminated) using the active energy ray-curable composition a in the same manner as described above. A layer was formed to prepare a hard coat film. The second hard coat layer had a thickness of 2.6 μm and a refractive index of 1.51.

<Active energy ray-curable composition a>
50 parts by mass of dipentaerythritol hexaacrylate, 37 parts by mass of an acrylate compound (“Aronix M111” manufactured by Toa Gosei Co., Ltd.), 8 parts by mass of the surface-treated silica particle dispersion A in terms of solid content, a photopolymerization initiator (Ciba 5 parts by mass of “Irgacure 184” manufactured by Specialty Chemicals Co., Ltd. was mixed with an organic solvent (methyl ethyl ketone).

[Example 2]
A hard coat film was produced in the same manner as in Example 1 except that the second hard coat layer was changed to the following active energy ray-curable composition b. The second hard coat layer had a thickness of 2.6 μm and a refractive index of 1.52.

<Active energy ray-curable composition b>
48 parts by mass of dipentaerythritol hexaacrylate, urethane acrylate oligomer (“UN-901T” from Negami Kogyo Co., Ltd .; containing 9 polymerizable functional groups in the molecule), photopolymerization initiator (Ciba Specialty) 5 parts by mass of “Irgacure 184” manufactured by Chemicals Co., Ltd. was dispersed and dissolved in an organic solvent (methyl ethyl ketone).

[Example 3]
A hard coat film was produced in the same manner as in Example 1 except that the active energy ray-curable composition for forming the first and second hard coat layers was changed to the following active energy ray-curable composition c. . The first and second hard coat layers each had a thickness of 2.6 μm and a refractive index of 1.51.

<Active energy ray-curable composition c>
87 parts by mass of dipentaerythritol hexaacrylate, 8 parts by mass of the surface-treated silica particle dispersion B in terms of solid content, and 5 parts by mass of a photopolymerization initiator (“Irgacure 184” manufactured by Ciba Specialty Chemicals Co., Ltd.) are organic solvents. (Methyl ethyl ketone) was prepared by mixing.

[Example 4]
A hard coat film was produced in the same manner as in Example 3 except that the second hard coat layer was changed to the active energy ray-curable composition b. The second hard coat layer had a thickness of 2.6 μm and a refractive index of 1.52.

[Example 5]
A hard coat film was produced in the same manner as in Example 1 except that the active energy ray-curable composition for forming the first and second hard coat layers was changed to the following active energy ray-curable composition d. . The first and second hard coat layers each had a thickness of 2.6 μm and a refractive index of 1.51.

<Active energy ray-curable composition d>
87 parts by mass of dipentaerythritol hexaacrylate, 8 parts by mass of the surface-treated silica particle dispersion C in terms of solid content, and 5 parts by mass of a photopolymerization initiator (“Irgacure 184” manufactured by Ciba Specialty Chemicals Co., Ltd.) are organic solvents. It was prepared by dispersing and dissolving in (a mixed solvent of methyl ethyl ketone and cyclohexanone having a mass ratio of 8: 2).

[Example 6]
A hard coat film was produced in the same manner as in Example 5 except that the second hard coat layer was changed to the active energy ray-curable composition b. The second hard coat layer had a thickness of 2.6 μm and a refractive index of 1.52.

[Example 7]
A hard coat film was produced in the same manner as in Example 1 except that the active energy ray-curable composition for forming the first and second hard coat layers was changed to the following active energy ray-curable composition e. . The first and second hard coat layers each had a thickness of 2.6 μm and a refractive index of 1.51.

<Active energy ray-curable composition e>
50 parts by mass of dipentaerythritol hexaacrylate, 37 parts by mass of an acrylate compound (“Aronix M111” manufactured by Toa Gosei Co., Ltd.), 8 parts by mass of the surface-treated silica particle dispersion D in terms of solid content, a photopolymerization initiator (Ciba 5 parts by mass of “Irgacure 184” manufactured by Specialty Chemicals Co., Ltd. was mixed with an organic solvent (methyl ethyl ketone).

[Example 8]
A hard coat film was produced in the same manner as in Example 7 except that the second hard coat layer was changed to the active energy ray-curable composition b. The second hard coat layer had a thickness of 2.6 μm and a refractive index of 1.52.

[Example 9]
A hard coat film was produced in the same manner as in Example 1 except that the active energy ray-curable composition for forming the first and second hard coat layers was changed to the following active energy ray-curable composition f. . The first and second hard coat layers each had a thickness of 2.6 μm and a refractive index of 1.51.

<Active energy ray-curable composition f>
50 parts by mass of dipentaerythritol hexaacrylate, 37 parts by mass of an acrylate compound (“Aronix M111” manufactured by Toa Gosei Co., Ltd.), 8 parts by mass of the surface-treated silica particle dispersion E in terms of solid content, a photopolymerization initiator (Ciba 5 parts by mass of “Irgacure 184” manufactured by Specialty Chemicals Co., Ltd. was mixed with an organic solvent (methyl ethyl ketone).

[Example 10]
A hard coat film was produced in the same manner as in Example 9 except that the second hard coat layer was changed to the active energy ray-curable composition b. The second hard coat layer had a thickness of 2.6 μm and a refractive index of 1.52.

[Comparative Example 1]
A hard coat film was produced in the same manner as in Example 1 except that the active energy ray-curable composition for forming the first and second hard coat layers was changed to the following active energy ray-curable composition g. . The first and second hard coat layers each had a thickness of 2.6 μm and a refractive index of 1.51.

<Active energy ray-curable composition g>
87 parts by mass of dipentaerythritol hexaacrylate, silica particles (“organosilica sol IPA-ST-ZL” manufactured by Nissan Chemical Industries, Ltd.) 8 parts by mass in terms of solid content, photopolymerization initiator (Ciba Specialty Chemicals Co., Ltd.) ) "Irgacure 184") 5 parts by mass was prepared by dispersing and dissolving in an organic solvent (a mixed solvent of methyl ethyl ketone and cyclohexanone having a mass ratio of 8: 2).

[Comparative Example 2]
A hard coat film was produced in the same manner as in Comparative Example 1 except that the second hard coat layer was changed to the active energy ray-curable composition b. The second hard coat layer had a thickness of 2.6 μm and a refractive index of 1.52.

[Comparative Example 3]
A hard coat film was produced in the same manner as in Example 1 except that the active energy ray-curable composition for forming the first and second hard coat layers was changed to the following active energy ray-curable composition h. . The first and second hard coat layers each had a thickness of 2.6 μm and a refractive index of 1.52.

<Active energy ray-curable composition h>
87 parts by mass of dipentaerythritol hexaacrylate, 8 parts by mass of polymethyl methacrylate particles (“MX-150H” manufactured by Soken Chemical Co., Ltd.) in terms of solid content, photopolymerization initiator (Ciba Specialty Chemicals Co., Ltd.) "Irgacure 184") was prepared by dispersing and dissolving 5 parts by mass in an organic solvent (a mixed solvent of methyl ethyl ketone and cyclohexanone having a mass ratio of 8: 2).

[Comparative Example 4]
A hard coat film was produced in the same manner as in Comparative Example 3 except that the second hard coat layer was changed to the active energy ray-curable composition b. The second hard coat layer had a thickness of 2.6 μm and a refractive index of 1.52.

[Example 11]
A hard coat film was produced in the same manner as in Example 1 except that the active energy ray-curable composition for forming the first and second hard coat layers was changed to the following active energy ray-curable composition i. . The first and second hard coat layers each had a thickness of 2.6 μm and a refractive index of 1.51.

<Active energy ray-curable composition i>
54 parts by mass of dipentaerythritol hexaacrylate, 37 parts by mass of an acrylate compound (“Aronix M111” manufactured by Toa Gosei Co., Ltd.), 4 parts by mass of the surface-treated silica particle dispersion A in terms of solid content, a photopolymerization initiator (Ciba 5 parts by mass of “Irgacure 184” manufactured by Specialty Chemicals Co., Ltd. was mixed with an organic solvent (methyl ethyl ketone).

[Example 12]
A hard coat film was produced in the same manner as in Example 1 except that the active energy ray-curable composition for forming the first and second hard coat layers was changed to the following active energy ray-curable composition j. . The first and second hard coat layers each had a thickness of 2.6 μm and a refractive index of 1.51.

<Active energy ray-curable composition j>
52 parts by mass of dipentaerythritol hexaacrylate, 37 parts by mass of an acrylate compound (“Aronix M111” manufactured by Toa Gosei Co., Ltd.), 6 parts by mass of the surface-treated silica particle dispersion A in terms of solid content, a photopolymerization initiator (Ciba 5 parts by mass of “Irgacure 184” manufactured by Specialty Chemicals Co., Ltd. was mixed with an organic solvent (methyl ethyl ketone).

[Example 13]
A hard coat film was produced in the same manner as in Example 1 except that the active energy ray-curable composition for forming the first and second hard coat layers was changed to the following active energy ray-curable composition k. . The first and second hard coat layers each had a thickness of 2.6 μm and a refractive index of 1.51.

<Active energy ray-curable composition k>
50 parts by mass of dipentaerythritol hexaacrylate, 35 parts by mass of an acrylate compound (“Aronix M111” manufactured by Toa Gosei Co., Ltd.), 10 parts by mass of the surface-treated silica particle dispersion A in terms of solid content, a photopolymerization initiator (Ciba 5 parts by mass of “Irgacure 184” manufactured by Specialty Chemicals Co., Ltd. was mixed with an organic solvent (methyl ethyl ketone).

[Example 14]
A hard coat film was produced in the same manner as in Example 1 except that the active energy ray-curable composition for forming the first and second hard coat layers was changed to the following active energy ray-curable composition l. . The first and second hard coat layers each had a thickness of 2.6 μm and a refractive index of 1.51.

<Active energy ray-curable composition l>
50 parts by mass of dipentaerythritol hexaacrylate, 33 parts by mass of an acrylate compound (“Aronix M111” manufactured by Toa Gosei Co., Ltd.), 12 parts by mass of the surface-treated silica particle dispersion A in terms of solid content, a photopolymerization initiator (Ciba 5 parts by mass of “Irgacure 184” manufactured by Specialty Chemicals Co., Ltd. was mixed with an organic solvent (methyl ethyl ketone).

[Comparative Example 5]
A hard coat film was produced in the same manner as in Example 1 except that the active energy ray-curable composition for forming the first and second hard coat layers was changed to the following active energy ray-curable composition m. . The first and second hard coat layers each had a thickness of 2.6 μm and a refractive index of 1.51.

<Active energy ray-curable composition m>
56 parts by mass of dipentaerythritol hexaacrylate, 37 parts by mass of an acrylate compound (“Aronix M111” manufactured by Toa Gosei Co., Ltd.), 2 parts by mass of the surface-treated silica particle dispersion A in terms of solid content, a photopolymerization initiator (Ciba 5 parts by mass of “Irgacure 184” manufactured by Specialty Chemicals Co., Ltd. was mixed with an organic solvent (methyl ethyl ketone).

[Comparative Example 6]
A hard coat film was produced in the same manner as in Example 1 except that the active energy ray-curable composition for forming the first and second hard coat layers was changed to the following active energy ray-curable composition n. . The first and second hard coat layers each had a thickness of 2.6 μm and a refractive index of 1.51.

<Active energy ray-curable composition n>
45 parts by mass of dipentaerythritol hexaacrylate, 30 parts by mass of an acrylate compound (“Aronix M111” manufactured by Toa Gosei Co., Ltd.), 20 parts by mass of the surface-treated silica particle dispersion A in terms of solid content, a photopolymerization initiator (Ciba 5 parts by mass of “Irgacure 184” manufactured by Specialty Chemicals Co., Ltd. was mixed with an organic solvent (methyl ethyl ketone).

[Comparative Example 7]
In the production of the resin layer laminated PET film of Example 1, a PET film having resin layers laminated on both sides in the same manner as in Example 1 except that the resin layer forming coating solution is changed to the resin layer forming coating solution b. Was made. Each of the resin layers laminated on both sides of the PET film had a refractive index of 1.52 and a thickness of 0.09 μm.

<Lamination of first and second hard coat layers>
The first and second hard coat layers were laminated on the above resin layer-laminated PET film in the same manner as in Comparative Example 5 to produce a hard coat film. The first and second hard coat layers each had a thickness of 2.6 μm and a refractive index of 1.51.

[Evaluation of hard coat film]
About the hard coat film of the Example obtained by the above and the comparative example, the structure of a 1st and 2nd hard coat layer is shown in Table 1, and the evaluation result of these hard coat films is shown in Table 2.

Moreover, the average diameter, average height, and average interval of the protrusions on the surface of the first hard coat layer were measured for representative samples in the above examples and comparative examples. The results are shown in Table 3.

From the above results, in Examples 1 to 14, since 300 to 10000 protrusions per unit area (100 μm ² ) are formed on the surface of the first hard coat layer, it can be said that the slipping property and the blocking resistance are good. . Further, the center line average roughness (Ra1, Ra2) of the first and second hard coat layers is less than 30 nm, the haze value of the hard coat film is less than 1.5%, and the transparency is good. Therefore, it can be said that the total light transmittance is high.

[Examples 15 to 24]
An ITO film as a transparent conductive film was laminated on the surface of the second hard coat layer of each of the hard coat films of Examples 1 to 10 by a sputtering method to produce a transparent conductive film. The slipperiness and blocking resistance of these transparent conductive films were evaluated. The results are shown in Table 4.

Incidentally, the evaluation of the slipperiness and blocking resistance of the transparent conductive film was conducted in the above-mentioned "(14) Evaluation of slipperiness" and "(15) Evaluation of blocking resistance" and the surface of the first hard coat layer was transparent. Evaluation was performed in the same manner except that the layers were overlapped so that the surface of the conductive film faced.

The transparent conductive films of Examples 15 to 24 were all good in slipping property and blocking resistance.

[Examples 25 to 29]
The following high refractive index layer and low refractive index layer were laminated in this order on the surface of the second hard coat layer of the hard coat films of Examples 2, 4, 6, 8, and 10, and then on the low refractive index layer. The following transparent conductive film was formed to produce a transparent conductive film for a capacitive touch panel.

<Lamination of high refractive index layer>
The following active energy ray-curable composition for forming a high refractive index layer is applied by a gravure coating method, dried at 90 ° C., and then cured by irradiation with ultraviolet rays of 400 mJ / cm ² to have a thickness of 50 nm. Formed. The refractive index of this high refractive index layer was 1.68.

(Active energy ray-curable composition for forming a high refractive index layer)
21 parts by mass of dipentaerythritol hexaacrylate, 21 parts by mass of urethane acrylate oligomer (“UN-901T” from Negami Kogyo Co., Ltd .; containing 9 polymerizable functional groups in the molecule), 55 parts by mass of zirconium oxide, and photopolymerization It was prepared by dispersing or dissolving 3 parts by mass of an initiator (“Irgacure 184” manufactured by Ciba Specialty Chemicals Co., Ltd.) in an organic solvent (propylene glycol monomethyl ether).

<Lamination of low refractive index layer>
The following active energy ray-curable composition for forming a low refractive index layer is applied by a gravure coating method, dried at 90 ° C., and then cured by irradiation with ultraviolet rays of 400 mJ / cm ² to form a low refractive index layer having a thickness of 40 nm. Formed. The refractive index of this low refractive index layer was 1.40.

(Active energy ray-curable composition for forming a low refractive index layer)
Di- (α-fluoroacrylic acid) -2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,9-heptadecafluorononylethylene glycol It was prepared by dispersing or dissolving 87 parts by mass, 10 parts by mass of dipentaerythritol hexaacrylate, and 3 parts by mass of a photopolymerization initiator (“Irgacure 184” manufactured by Ciba Specialty Chemicals Co., Ltd.) in an organic solvent (methyl ethyl ketone).

<Lamination of transparent conductive film>
An ITO film was laminated by a sputtering method so as to have a thickness of 25 nm, and a transparent conductive film was formed by pattern processing (etching treatment) into a lattice pattern.

[Evaluation]
For the transparent conductive films of Examples 25 to 29, the slipperiness, blocking resistance, and visibility of the transparent conductive film pattern were evaluated. The results are shown in Table 5.

All of the transparent conductive films of Examples 25 to 29 showed good slipperiness, blocking resistance, and visibility of the transparent conductive film pattern.

[Examples 31 to 40]
As shown below, five types of coating liquids for forming a resin layer having different wetting tensions were prepared.

(Resin layer forming coating solution c; wetting tension 42 mN / m)
In the solid content mass ratio, 27% by mass of the following polyester resin c, 54% by mass of the polyester resin d, 18% by mass of the melamine-based crosslinking agent, and 1% by mass of the particles were mixed to prepare an aqueous dispersion coating solution.
Polyester resin c: a polyester resin composed of 43 mol% of 2,6-naphthalenedicarboxylic acid / 5 mol% of 5-sodium sulfoisophthalic acid / 45 mol% of ethylene glycol / 5 mol% of diethylene glycol.
Polyester resin d: polyester resin composed of terephthalic acid 38 mol% / trimellitic acid 12 mol% / ethylene glycol 45 mol% / diethylene glycol 5 mol%.
・ Melamine-based cross-linking agent; “Nicarac MW12LF” manufactured by Sanwa Chemical Co., Ltd.
Particles: colloidal silica having an average particle size of 0.19 μm.

(Resin layer forming coating solution d; wetting tension 44 mN / m)
In terms of solid content, 42% by mass of the following polyester resin e, 42% by mass of acrylic resin a, 6% by mass of the epoxy-based crosslinking agent, 9% by mass of the surfactant, and 1% by mass of the particles are mixed to form water. A dispersion coating solution was prepared.
Polyester resin e: terephthalic acid 35 mol% / isophthalic acid 11 mol% / 5-sodium sulfoisophthalic acid 4 mol% / ethylene glycol 45 mol% / diethylene glycol 4 mol% / polyethylene glycol (number of repeating units n = 23) 1 mol % Polyester resin.
Acrylic resin a: acrylic resin composed of 75 mol% of methyl methacrylate / 18 mol% of ethyl acrylate / 4 mol% of N-methylol acrylamide / methoxypolyethylene glycol (number of repeating units n = 10) 3 mol% of methacrylate.
Epoxy-based crosslinking agent; 1,3-bis (N, N-diglycidylamine) cyclohexane surfactant, polyoxyethylene lauryl ether particle, colloidal silica having an average particle size of 0.19 μm.

(Resin layer forming coating solution e; wetting tension 48 mN / m)
The following polyester resin f is 40% by mass, acrylic resin b is 40% by mass, melamine-based cross-linking agent is 10% by mass, surfactant is 9% by mass, and particles are 1% by mass in terms of solid content by mass. A dispersion coating solution was prepared.
Polyester resin f: a polyester resin composed of terephthalic acid 30 mol% / isophthalic acid 15 mol% / 5-sodium sulfoisophthalic acid 5 mol% / ethylene glycol 30 mol% / 1,4-butanediol 20 mol%.
・ Acrylic resin b: acrylic resin composed of 75 mol% of methyl methacrylate / 22 mol% of ethyl acrylate / 1 mol% of acrylic acid / 2 mol% of N-methylolacrylamide ・ Melamine cross-linking agent; manufactured by Sanwa Chemical Co., Ltd. "Nikarak MW12LF"
-Surfactant; Polyoxyethylene lauryl ether-Particles; Colloidal silica having an average particle size of 0.19 μm.

(Resin layer forming coating solution f; wetting tension 51 mN / m)
The following polyester resin g is 45% by mass, acrylic resin c is 45% by mass, melamine-based crosslinking agent is 5% by mass, surfactant is 4% by mass, and particles are 1% by mass in terms of solid content by mass. A dispersion coating solution was prepared.
Polyester copolymer g: A polyester copolymer composed of terephthalic acid 32 mol% / isophthalic acid 12 mol% / 5-sodium sulfoisophthalic acid 6 mol% / ethylene glycol 46 mol% / diethylene glycol 4 mol%.
Acrylic resin c: an acrylic copolymer composed of 70 mol% methyl methacrylate / 22 mol% ethyl acrylate / 4 mol% N-methylolacrylamide / 4 mol% N, N-dimethylacrylamide.
・ Melamine-based cross-linking agent; “Nicarac MW12LF” manufactured by Sanwa Chemical Co., Ltd.
-Surfactant; Polyoxyethylene lauryl ether-Particles; Colloidal silica having an average particle size of 0.19 μm.

(Resin layer forming coating solution g; wetting tension 53 mN / m)
A coating liquid was prepared by mixing 85% by mass of urethane resin, 5% by mass of epoxy-based crosslinking agent, 9% by mass of surfactant, and 1% by mass of particles in a solid content mass ratio.
-Urethane resin: "Hydran AP-20" manufactured by Dainippon Ink & Chemicals, Inc.
・ Epoxy-based cross-linking agent; triethylene glycol diglycidyl ether ・ surfactant; polyoxyethylene lauryl ether ・ particles;

[Example 31]
A hard coat film was prepared in the following manner.

<Production of resin layer laminated PET film>
A resin layer was in-line coated on both sides of a polyethylene terephthalate film (PET film) having a refractive index of 1.65 and a thickness of 100 μm within the PET film manufacturing process. That is, the resin layer forming coating solution c is applied to both surfaces of a PET film uniaxially stretched in the longitudinal direction by a bar coating method, dried at 100 ° C., then biaxially stretched in the width direction and heated at 230 ° C. for 20 seconds. The PET film in which the resin layer was laminated | stacked on both surfaces was processed and heat-cured. The thickness of the resin layer laminated | stacked on both surfaces of PET film was 0.08 micrometer, respectively.

<Lamination of first and second hard coat layers>
The active energy ray-curable composition a used in Example 1 was applied by the gravure coating method on the resin layer on one side of the PET film having the resin layers laminated on both sides, dried at 90 ° C., and then irradiated with ultraviolet rays 400 mJ. / Cm ² was irradiated and cured to form a first hard coat layer. The thickness of the first hard coat layer was 1.6 μm.

Next, the active energy ray-curable composition b used in Example 2 is formed in the same manner as above on the resin layer on the other side of the PET film (the side opposite to the side on which the first hard coat layer is laminated). A second hard coat layer was formed to produce a hard coat film. The thickness of this second hard coat layer was 1.6 μm.

[Examples 32 to 35]
A hard coat film was produced in the same manner as in Example 31 except that the resin layer forming coating solution was changed as shown in Table 6.

[Examples 36 to 40]
A hard coat film was produced in the same manner as in Examples 31 to 35 except that the thickness of the first hard coat layer was changed to 2.6 μm and the thickness of the second hard coat layer was changed to 2.6 μm. .

[Evaluation of hard coat film]
For the hard coat films of Examples 31 to 40 obtained above, the structures of the first and second hard coat layers are shown in Table 6, and the evaluation results of these hard coat films are shown in Table 7.

From the above results, it can be seen that by laminating the first hard coat layer directly on the resin layer having a wetting tension of 52 mN / m or less, protrusions due to particles are easily formed on the surface of the first hard coat layer (unit area) It can be seen that the number of projections per hit increases.) And it turns out that the influence of the wetting tension | tensile_strength of the resin layer surface becomes remarkable when the thickness of a 1st hard-coat layer is less than 2 micrometers. That is, the aspect in which the first hard coat layer is directly laminated on the resin layer having a wetting tension of 52 mN / m or less is contained in the first hard coat layer when the thickness of the first hard coat layer is less than 2 μm. Particles are likely to be unevenly distributed in the vicinity of the surface, and as a result, protrusions made of particles are efficiently formed. Moreover, by making the thickness of the first hard coat layer less than 2 μm, the haze value becomes smaller and the transparency is improved.

1 to 5 Protrusion 11 Protrusion 20 Horizontal straight line 30 Vertical straight line

Claims

A first hard coat layer containing particles is provided on at least one surface of the base film, and protrusions made of the particles are present on the surface of the first hard coat layer at a density of 300 to 4000 per 100 μm 2 The hard coat film characterized by having a center line average roughness (Ra1) of the surface of the first hard coat layer of less than 30 nm and a haze value of less than 1.5%.
2. The hard coat film according to claim 1, wherein an average particle diameter (r) of the particles is 0.05 to 0.5 μm.
3. The hard coat film according to claim 1, wherein the ratio (r / d) of the average particle diameter (r) of the particles to the thickness (d) of the first hard coat layer is 0.01 to 0.30.
4. The hard coat film according to claim 1, wherein an average diameter of the protrusions is 0.03 to 0.3 μm, and an average height of the protrusions is 0.03 to 0.3 μm.
The hard coat film according to any one of claims 1 to 4, wherein an average interval between the protrusions is 0.10 to 0.70 µm.
The hard coat film according to claim 1, wherein the thickness (d) of the first hard coat layer is 0.5 μm or more and less than 10 μm.
A resin layer having a thickness of 0.005 to 0.3 μm is provided between the base film and the first hard coat layer, and the resin layer has particles having an average particle diameter of 1.3 times or more of the thickness. The hard coat film according to any one of claims 1 to 6, which is contained.
The base film is made of polyethylene terephthalate, and a resin layer having a refractive index of 1.55 to 1.61 is provided between the base film and the first hard coat layer. Hard coat film as described in 2.
The hard coat film according to any one of claims 1 to 8, further comprising a resin layer having a wetting tension of 52 mN / m or less between the base film and the first hard coat layer.
The hard coat film according to claim 9, wherein the first hard coat layer has a thickness of less than 2 μm.
The particle according to any one of claims 1 to 10, wherein the particles contained in the first hard coat layer are made of an inorganic substance, and the surface of the particles is subjected to a treatment for reducing surface free energy or a hydrophobic treatment. The hard coat film as described.
An organosilane compound represented by the general formula 1 (C n F 2n + 1 — (CH 2 ) m —Si (Q) 3 ) is added to the surface of the particles contained in the first hard coat layer. The hard coat film according to claim 11, wherein a treatment for reducing surface free energy is performed using a decomposition product or a partial condensate of the hydrolysis product.
In general formula 1, n represents an integer of 1 to 10, m represents an integer of 1 to 5, and Q represents an alkoxy group having 1 to 5 carbon atoms or a halogen atom.
After the surface of the particles contained in the first hard coat layer is treated with a compound represented by the general formula 2 (BR 4 —SiR 5 n (OR 6 ) 3-n ), the general formula 3 The hard coat film according to claim 11, which has been hydrophobized by treatment with a fluorine compound represented by (DR 7 -Rf 2 ).
However, in the general formulas 2 and 3, B and D each independently represent a reactive site, and R 4 and R 7 each independently represent an alkylene group having 1 to 3 carbon atoms or an ester structure derived from the alkylene group R 5 and R 6 each independently represent hydrogen or an alkyl group having 1 to 4 carbon atoms, Rf 2 represents a fluoroalkyl group, and n represents an integer of 0 to 2.
The surface of the particle contained in the first hard coat layer has a fluorine compound having a fluoroalkyl group having 4 or more carbon atoms and a reactive site, a long chain having a hydrocarbon group having 8 or more carbon atoms and a reactive site. The hard coat film according to claim 11, which is hydrophobized by being treated with a hydrocarbon compound or a silicone compound having a siloxane group and a reactive site.
The hard coat film according to any one of claims 1 to 14, wherein the particles contained in the first hard coat layer are silica particles.
The base film is provided with a second hard coat layer on the surface opposite to the surface on which the first hard coat layer is provided, the surface of the second hard coat layer is substantially free of protrusions made of particles, and The hard coat film according to any one of claims 1 to 15, wherein the center line average roughness (Ra2) of the surface of the second hard coat layer is 25 nm or less.
A transparent conductive film comprising a transparent conductive film on at least one surface of the hard coat film according to any one of claims 1 to 16.