JP2018065978A - Energy ray-curable antistatic hard coat resin composition, antistatic film and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an energy ray-curable antistatic hard coat resin composition that has excellent transparency, substantially causes no problem in dispersibility, and exhibits excellent antistatic performance.SOLUTION: An energy ray-curable antistatic hard coat resin composition contains carbon nanotubes with an average length of 5 μm or more, and an energy ray-curable resin. The concentration of the carbon nanotubes in the nonvolatile content of the composition is 0.03 wt.% or more and less than 0.15 wt.%.SELECTED DRAWING: None

Description

The present invention relates to an energy ray curable antistatic hard coat resin composition, an antistatic treatment film, and a method for producing the same.

Providing antistatic performance to a film by forming an antistatic layer containing a conductive material on a base film is a widely practiced matter in many technical fields. In such an antistatic layer, a composition in which conductive particles such as carbon black, ZnO, ITO, ATO, and SbO ₂ are blended with an energy ray curable resin is used (Patent Document 1, etc.).

However, since such conductive particles are usually blended in a large amount of 1% by weight or more, properties such as film strength and optical properties (light transmittance, refractive index, etc.) are affected. For this reason, it is very desirable to have a conductive material that can provide sufficient antistatic performance with a smaller amount.

Carbon nanotubes are attracting attention as a material having high conductivity, and various studies have been conducted for practical use. Patent Documents 2, 3, 4 and the like have been studied about use as a resin composition for hard coat in combination with an energy ray curable resin.

However, when blended into such a hard coat, it is usually blended at a ratio of 1% by weight or more, and even if blended at a ratio lower than this, it is considered that an antistatic effect cannot be obtained. It was. Furthermore, since a composition containing a large amount of carbon nanotubes exhibits thixotropic properties, this may adversely affect the coating performance. That is, it has been difficult to obtain a thin coating film due to an increase in viscosity.

Patent Documents 2 and 3 describe forming a hard coat layer containing carbon nanotubes on an antireflection film. However, in order to compensate for the poor dispersibility of carbon nanotubes, it is essential to use fullerene in combination. Further, since the blending amount is 1% by weight or more, problems such as deterioration of transparency and influence on the refractive index are regarded as problems.

Patent Document 4 discloses that an antistatic layer is formed by a composition containing carbon nanotubes and a binder resin. However, in reality, it is desired to add 1% by weight or more of carbon nanotubes. For this reason, transparency and thin film moldability were not favorable.

Furthermore, Patent Document 5 describes the use of carbon nanotubes having a specific shape. However, in Patent Document 5, there is no description regarding the use of carbon nanotubes as the conductive component in the hard coat layer.

JP 09-115334 A Japanese Patent Application Laid-Open No. 2013-2055887 JP 2012-203093 A JP 2008-168591 A Japanese Patent Laid-Open No. 2006-54068

In view of the above, the present invention provides an energy ray curable antistatic hard coat resin composition that is excellent in transparency, hardly causes problems in dispersibility, can be coated with a thin film, and exhibits excellent antistatic performance. It is intended.

The present invention contains carbon nanotubes having an average length of 5 μm or more and an energy ray curable resin,
The carbon nanotube is an energy ray curable antistatic hard coat resin composition characterized in that the concentration in the nonvolatile content of the composition is 0.03% by weight or more and 0.15% by weight or less.
The energy ray curable antistatic hard coat resin composition is preferably solventless.
The present invention is also an antistatic treatment film characterized in that the energy ray-curable antistatic hard coat resin composition described above has a resin layer obtained by energy ray curing on a base film.

The present invention includes a step (1) of applying the above-described energy beam curable antistatic hard coat resin composition on a base film and a step (2) of performing energy beam curing.
It is also a manufacturing method of the antistatic treatment film characterized by having.

The energy beam curable antistatic hard coat resin composition of the present invention is excellent in transparency, has little change in refractive index due to the incorporation of a conductive material, is less likely to cause dispersibility problems, and is easy to apply to a thin film. Also, the coating film performance is good and exhibits excellent antistatic performance.

It is a figure which shows the relationship between the compounding quantity of the carbon nanotube in the antistatic treatment film of an Example, and a surface resistance value. It is a figure which shows the relationship between the compounding quantity of the carbon nanotube in the antistatic process film of an Example, and 550 nm ultraviolet-ray transmittance.

Hereinafter, the present invention will be described in detail.
The present invention is characterized by blending carbon nanotubes having a specific shape with an average length of 5 μm or more. That is, when carbon nanotubes having a long shape in the long axis direction are used in this way, it is easy to ensure conductivity even if the blending amount is as low as 0.15% by weight or less. Can be obtained.

Furthermore, liquid compositions containing a large amount of carbon nanotubes tend to be difficult to control the viscosity due to the development of thixotropic properties. However, in the composition of the present invention, since the composition of carbon nanotubes is small, it is difficult to increase the viscosity. It is also preferable in that it is easy to handle. Furthermore, since the compounding quantity of a carbon nanotube is very low, transparency is also favorable and can be used conveniently also in the use for which transparency is requested | required. Moreover, since the influence with respect to the refractive index of resin is small, it can be used suitably also as an antistatic hard-coat layer of the optical field | area which needs control of a refractive index.

The carbon nanotube used in the present invention has an average length of 5 μm or more. The average length of the carbon nanotubes in the present invention was obtained by forming a hard coat layer on a PET film with the energy ray curable antistatic hard coat resin composition of the present invention by the method described in the examples. The film is observed with a digital microscope having a magnification of 1000 times or more, and the length of the carbon nanotube is calculated by image analysis software for all particles present in the image. It is the average value of the length of the particle | grains measured about particle | grains. The average length is more preferably 6 μm or more, and further preferably 7 μm or more. The upper limit of the average length is not particularly limited, but is preferably 50 μm or less, and more preferably 30 μm or less.

In the present invention, the carbon nanotube may be any of a single-walled carbon nanotube, a double-walled carbon nanotube, and a multilayer carbon nanotube having three or more layers, but a multilayer carbon nanotube having three or more layers can be preferably used. More specifically, the carbon nanotube is preferably 3 to 50 layers.

The carbon nanotubes are synthesized and manufactured by an arc discharge method, a laser ablation method, a chemical vapor deposition method, or the like, and among them, the chemical vapor deposition method is preferable.

More specifically, the carbon nanotubes that can be used in the present invention can be produced by the method described in detail in JP-A-2006-54068. Moreover, as a commercially available thing,
A length of 50 μm or less, preferably 5-15 μm, a diameter of 10-100 nm, preferably 60-100 nm can be used.

In the energy ray-curable antistatic hard coat resin composition of the present invention, the content of carbon nanotubes is 0.03% by weight or more and 0.15% by weight or less in terms of the concentration in the nonvolatile content of the composition. That is, when carbon nanotubes such as those described above are used, it has been found that sufficient antistatic performance can be obtained even when carbon nanotubes are blended at an extremely lower proportion than the amount generally studied in the past. Thus, it is possible to provide an energy ray curable antistatic hard coat resin composition that is highly transparent and hardly causes a dispersion problem.

If the carbon nanotube content is less than 0.03% by weight, sufficient charging performance cannot be obtained. If it exceeds 0.15% by weight, the light transmittance is lowered, which is disadvantageous in terms of cost. Moreover, since the thixotropy becomes strong when the compounding amount of the carbon nanotube is increased, it becomes difficult to form a thin film due to difficulty in controlling the viscosity at the time of coating.
The lower limit is more preferably 0.035% by weight, still more preferably 0.04% by weight. The upper limit is more preferably 0.10% by weight, more preferably 0.09% by weight, and still more preferably 0.05% by weight.

The energy beam curable antistatic hard coat resin composition of the present invention preferably has a transmittance at 550 nm of 80% or more. In the present invention, since a very small amount of carbon nanotube is blended, it is possible to maintain high transparency. Thereby, it can be used particularly in an optical film that requires high transparency. Here, “the transmittance at 550 nm is 80% or more” means that a coating layer having a thickness of 10 μm is formed on the PET film by the method described in the Examples, and the transmittance at 550 nm is measured for this coating film. It means that it becomes 80% or more.

The energy curable antistatic hard coat resin composition of the present invention contains an energy ray curable resin. That is, the resin is cured by irradiating energy rays such as ultraviolet rays. The energy ray curable resin used here is not particularly limited, and an arbitrary one can be used. Moreover, you may use it, mixing 2 or more types of components. Moreover, it is preferable to contain the radically polymerizable photoinitiator (D) for hardening energy beam curable resin.

As the energy ray curable resin, in particular, a base resin (A) having a (meth) acryloyl group, a monomer (B) having two or more (meth) acryloyl groups, and a monofunctional unsaturated having a (meth) acryloyl group A composition using the monomer (C) or a mixture thereof in combination with the radical polymerizable photopolymerization initiator (D) is preferable.
Each component that can be used as these energy ray curable resins will be described in detail below.

(Base resin having (meth) acryloyl group (A))
The base resin (A) having the (meth) acryloyl group preferably has two or more (meth) acryloyl groups in the molecule and has a viscosity of 100 Pa · s (25 ° C.) or more. . As the molecular weight, the number average molecular weight is preferably more than 800.

As such a compound, a great many kinds of compounds are known. Among them, (meth) acrylic esters of aromatic epoxides having a hydroxyl group in the molecule and urethane acrylic resins having a urethane group in the molecule ( Urethane prepolymer) is preferred. More specifically, for example, a (meth) acrylic acid adduct of bisphenol A diglycidyl ether (for example, epoxy ester 3000A manufactured by Kyoeisha Chemical Co., Ltd.) or pentaerythritol tri (meth) acrylate hexamethylene diisocyanate urethane prepolymer (for example, Kyoeisha Chemical Co., Ltd. UA-306H, Kyoeisha Chemical Co., Ltd. UABC-306H), Bisphenol A PO2 mol adduct diglycidyl ether acrylic acid adduct (for example, Kyoeisha Chemical Co., Ltd. epoxy ester 3002A), pentaerythritol triacrylate toluene diisocyanate urethane pre Polymer (for example, UA-306T manufactured by Kyoeisha Chemical Co., Ltd.), pentaerythritol triacrylate isophorone diisocyanate urethane prepolymer (for example, Kyoeisha) Company Ltd. UA-306I), UF-8001G, can be cited BPZA-66, UF-HK75 (manufactured by Kyoeisha Chemical Co., Ltd.).

(Monomer (B) having two or more (meth) acryloyl groups)
Such a monomer is preferably a relatively low molecular weight having a molecular weight of 180 to 800, and any compound having two or more (meth) acryloyl groups can be used. As such a compound, a great many kinds are known, but any of these can be used in the present application. Two or more of these can be used in combination. Specific examples of these are given below.

Examples of (meth) acrylates having 2 functional groups are 1,4-butanediol di (meth) acrylate, 1,3-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, ethylene glycol Di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, polypropylene glycol Di (meth) acrylate, neopentyl glycol di (meth) acrylate, hydroxypivalic acid neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9 Nonanediol di (meth) acrylate, 1,10-decanediol di (meth) acrylate, glycerin di (meth) acrylate, dimethylol-tricyclodecane di (meth) acrylate (DCP-A), EO adduct of bisphenol A Diacrylate (manufactured by Kyoeisha Chemical; Light acrylate BP-4EA, BP-10EA) PO adduct diacrylate of bisphenol A (manufactured by Kyoeisha Chemical; BP-4PA, BP-10PA, etc.). Among them, bisphenol A PO adduct diacrylate (manufactured by Kyoeisha Chemical Co., Ltd .; BP-4PA), dimethylol-tricyclodecane di (meth) acrylate (DCP-A) and the like can be preferably used.

Examples of the (meth) acrylate having 3 functional groups are trimethylolmethane tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane ethylene oxide modified tri (meth) acrylate, trimethylolpropane propylene oxide modified tri ( (Meth) acrylate, pentaerythritol tri (meth) acrylate, glycerin propoxytri (meth) acrylate, tris (2- (meth) acryloyloxyethyl) isocyanurate and the like. Of these, trimethylolpropane trimethacrylate, pentaerythritol trimethacrylate, and the like can be preferably used.

Examples of (meth) acrylates having 4 functional groups are dipentaerythritol tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol ethylene oxide modified tetra (meth) acrylate, pentaerythritol propylene oxide modified tetra (meth) acrylate. , Ditrimethylolpropane tetra (meth) acrylate and the like. Of these, ditrimethylolpropane tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, and the like can be preferably used.

Examples of (meth) acrylates having 4 or more functional groups include pentaerythritol tetra (meth) acrylate, pentaerythritol ethylene oxide modified tetra (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate, Dipentaerythritol penta (meth) acrylate, ditrimethylolpropane penta (meth) acrylate, propionic acid-modified dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, ditrimethylolpropane hexa (meth) acrylate, dipenta Examples include polyfunctional (meth) acrylates such as hexa (meth) acrylate of a caprolactone modified product of erythritol.

(Monofunctional unsaturated monomer having (meth) acryloyl group (C))
The monofunctional unsaturated monomer (C) having the (meth) acryloyl group is not particularly limited, and 1,4-butanediol monomethacrylate, 1,6-hexanediol monomethacrylate, 1,9-nonanediol monomethacrylate, Examples include 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 2-hydroxybutyl acrylate, and 2-hydroxybutyl methacrylate. In addition, benzyl (meth) acrylate having a phenyl group in the molecule, phenoxyethyl (meth) acrylate, ethoxyphenoxyethyl (meth) acrylate, phenoxybenzyl (meth) acrylate, phenol ethylene oxide-modified methacrylate, a length of 12 to 16 carbon atoms (Meth) acrylate monomer having a chain alkyl group [e.g., Kyoeisha Chemical Co., Ltd. trade name light ester L-7 (alkyl (carbon number 12 to 13) methacrylate), light ester L (n-lauryl methacrylate), NOF Trade name Blemmer LMA (n-lauryl methacrylate), Blemmer SLMA-S or SH (alkyl (alkyl of 12 to 13 carbon atoms)), Blemmer CMA (cetyl methacrylate), Blemmer LA (lauryl acrylate), Blen Mercer CA (cetyl acrylate) etc.] can also be used. Aromatic (meth) acrylic monomers with good dispersibility and (meth) acrylate monomers of flexible long-chain alkyl alcohols can be used, and these can be used alone or in combination of two or more.

  Moreover, as a monofunctional (meth) acrylate whose main chain is an aliphatic group, dicyclopentenyloxyethyl acrylate, dicyclopentenyloxyethyl methacrylate, dicyclopentanyl acrylate, dicyclopentanyl methacrylate, phenol ethylene oxide modified acrylate, Isoboronyl (meth) acrylate and the like can be used. In addition, Daicel Corporation has a hydroxyl group such as Plaxel FA1, FA2D, FA3, FM1D, FM2D, FM3 [these are caprolactone adducts of hydroxyethyl acrylate (HEA) or hydroxyethyl methacrylate (HEMA)]. (Meth) acrylate monomers can be used. It is also possible to use an unsaturated monobasic acid which is a reaction product of a monofunctional (meth) acrylate having one hydroxyl group in the molecule and a saturated dibasic acid. These can be used alone or in combination of two or more.

The present invention may be used in combination of two or more of (A) to (C) described above, and is a resin composition used in combination with (A) to (C). Is most preferred. Use of these in combination is preferred in that excellent properties are obtained in terms of good dispersibility, transparency, film performance after curing, and the like.

When the resin composition is used in combination with (A) to (C), the base resin (A) having the (meth) acryloyl group is included in the nonvolatile content of the energy ray curable antistatic hard coat resin composition. The concentration is preferably 30% by weight or more and less than 70% by weight. If it is less than 30% by weight, the dispersion stability of the nanotubes due to a decrease in viscosity may decrease, and a problem that hard coat performance after UV curing cannot be exhibited due to insufficient coating hardness due to a decrease in crosslinking density may occur. If it exceeds 70% by weight, the viscosity becomes so high that coating becomes difficult and the crosslink density increases, the cure shrinkage rate increases, the electrical properties decrease, the adhesiveness with the substrate decreases, and the peeling from the substrate occurs. May occur.
The lower limit is more preferably 35% by weight and even more preferably 40% by weight. The upper limit is more preferably 65% by weight and even more preferably 50% by weight.

When the resin composition is used in combination with (A) to (C), the monomer (B) having two or more (meth) acryloyl groups is a non-volatile component of the energy ray curable antistatic hard coat resin composition. It is preferable that the concentration is 20% by weight or more and less than 50% by weight. If it is less than 20% by weight, there is a possibility that the crosslinking density is low and sufficient hardness cannot be obtained. If it exceeds 50% by weight, the crosslink density becomes too large, and there is a possibility that the electrical properties are lowered and the adhesion to the substrate is lowered and the substrate adhesion is lowered.
The lower limit is more preferably 25% by weight and even more preferably 30% by weight. The upper limit is more preferably 40% by weight and even more preferably 35% by weight.

When the resin composition is used in combination with (A) to (C), the above (monofunctional unsaturated monomer (C) having a (meth) acryloyl group) is an energy ray curable antistatic hard coat resin composition. The concentration in the nonvolatile content of the product is preferably 15% by weight or more and less than 40% by weight. If it is less than 15% by weight, the viscosity becomes high, which may cause a problem that coating becomes difficult. If it exceeds 40% by weight, the crosslinking density is lowered, and there is a fear that the hardness as a hard coat is insufficient.
The lower limit is more preferably 20% by weight, and even more preferably 22.5% by weight. The upper limit is more preferably 30% by weight and even more preferably 26% by weight.

(Radical polymerizable photopolymerization initiator (D))
The energy beam curable antistatic hard coat resin composition of the present invention preferably contains a radical polymerizable photopolymerization initiator (D). That is, in the processing step, since curing is performed with energy rays, it is desirable to add such components.

The radical polymerizable photopolymerization initiator (D) is not particularly limited, and examples thereof include hydroxycyclohexyl phenyl ketone (Irgacure # 184 manufactured by Ciba), 2,2-dimethoxy-2-phenylacetophenone (Irgacure # 651 manufactured by Ciba). ), 2-hydroxy-2-methyl-1-phenylpropan-1-one (Darocur # 1173 manufactured by Ciba), 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (TPO manufactured by Ciba), 2-benzyl- 2-dimethylamino-1- (4-morpholinophenylbutanone (Irgacure # 369 manufactured by Ciba), 2-methyl-1- [4- (methylthio) phenyl] -2- (4-morpholinyl) -1-propanone (Ciba Irgacure # 907), bis (2,4,6-trimethylbenzoyl) -fe Nilphosphine oxide (Irgacure # 819, manufactured by Ciba Co., Ltd.), etc. These may be used alone or in combination of two or more.
A sensitizer such as diethyl thioxanthone, isopropyl thioxanthone, Kawasaki Kasei Anthracure UVS-581 can be used in combination.

Of these, hydroxycyclohexyl phenyl ketone (Irgacure # 184 manufactured by Ciba) and 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (TPO manufactured by Ciba) are particularly preferably used alone or in combination.

It is preferable that the compounding quantity of the said photoinitiator is 0.1 to 10 weight% with respect to the non volatile matter of an energy-beam curable antistatic hard coat resin composition. The lower limit is more preferably 0.5% by weight, still more preferably 3% by weight. The upper limit is more preferably 4% by weight. The lower limit of the amount of the photopolymerization initiator is preferably 0.1% by weight, more preferably 0.3% by weight. The upper limit of the amount of the photopolymerization initiator is preferably 1% by weight.

(Other ingredients (E))
In the energy beam curable antistatic hard coat resin composition of the present invention, in addition to the above-described components, ordinary components blended in the field can be used as long as the physical properties are not adversely affected. Examples of such components include dispersants, antifoaming agents, surface conditioners, silane coupling agents such as allylsilane and alkoxysilane.

The energy ray curable antistatic hard coat resin composition of the present invention preferably has an organic solvent content of 5% by weight or less. That is, it is desirable in that it can be used substantially without a solvent. This is preferable in that the influence on the environment is small. Furthermore, the organic solvent may not be contained at all.

Here, the “organic solvent” refers to a volatile organic compound that is removed by volatilization from the molded product after molding and before heat treatment, and is generally used as a “solvent” in the paint field. Refers to things.

The energy ray curable antistatic hard coat resin composition of the present invention may contain a conductive filler other than carbon nanotubes as long as the effects of the present invention are not impaired. It is preferable that it is 3 weight% or less with respect to the total amount. When a large amount of other antistatic agent is blended, there is a possibility that bleeding from the cured resin will occur over time. This is not preferable because it may deteriorate performance and optical properties.

In particular, carbon-based conductive materials other than carbon nanotubes, such as carbon black and fullerene, are not used or preferably 1% by weight even when used. Since these carbon-based conductive materials are black, they are not preferable in that they easily affect optical characteristics such as a decrease in light transmittance.

The production method of the energy ray curable antistatic hard coat resin composition of the present invention is not particularly limited, and can be obtained by mixing the above-described components by a usual method. The carbon nanotubes can be uniformly dispersed in the composition by being dispersed in a small amount of a liquid component using a dispersant as required, and then mixed with other components.

The present invention includes a step (1) of applying the above-described energy beam curable antistatic hard coat resin composition on a base film and a step (2) of performing energy beam curing.
It is also a manufacturing method of the antistatic treatment film characterized by having.
By having such a layer, it is preferable in that antistatic properties can be imparted without affecting the physical properties and optical properties inherent to the hard coat layer.

Examples of the base film used in the above method include a PET film, a polyacetal film, a polycarbonate film, an acrylic film, and a polyolefin film.

When the antistatic layer is formed by the above method, the thickness of the antistatic layer is not particularly limited, but can be 5 to 20 μm. The upper limit is more preferably 15 μm. In particular, the energy ray curable antistatic hard coat resin composition of the present invention is preferable in that a thin film can be formed at a thickness of 10 μm or less.

Step (1) and step (2) described above can be performed by a normal method. Moreover, the antistatic treatment film obtained by the above-described production method may have a necessary layer other than the coating layer formed by the energy ray curable antistatic hard coat resin composition, if necessary. Good.

The present invention is also an antistatic treatment film having a resin layer obtained by curing the energy beam curable antistatic hard coat resin composition as described above.
The antistatic treatment film of the present invention preferably has a coating layer thickness of 5 to 20 μm. If it is 5 μm or less, it is difficult to obtain sufficient antistatic performance and it is difficult to form a uniform layer, which is not preferable. If it exceeds 20 μm, it is not preferable because it causes an increase in cost and transparency may be lowered.

The antistatic treatment film of the present invention preferably has a transmittance at 550 nm of 80% or more. In the present invention, since a very small amount of carbon nanotube is blended, it is possible to maintain high transparency. Thereby, it can be used particularly in an optical film that requires high transparency.

The antistatic film of the present invention preferably has a surface resistance value of 10 ¹⁴ Ω / □ or less. By setting it as such a range, favorable antistatic performance can be exhibited.

The antistatic treatment film of the present invention can be used in various arbitrary applications such as an optical film such as a liquid crystal film, a packaging resin film, and a protective film for transporting precision electronic materials that dislike charging.

EXAMPLES Hereinafter, although this invention is demonstrated based on an Example, this invention is not limited to what was described in the following example.
In addition, unless specifically limited in an Example, a compounding quantity shows weight%.

Example 1
1. Base 6-functional urethane acrylate (UA-306H) (corresponds to (A)) 42 parts by weight 2. Pentaerythritol tetraacrylate (PE-4A) (corresponding to (B)) 10 parts by weight Bisphenol A-bis (oxydiethylene glycol) diacrylate (BP-4EA) (corresponds to (B)) 22 parts by weight 4. Phenoxyethyl acrylate (PO-A) (corresponds to (C)) 22 parts by weight Isobornyl acrylate (IB-XA) (corresponds to (C)) 4 parts by weight
Total above = 100 parts by weight5. Carbon nanotube 0.0195 parts by weight6. Photopolymerization initiator 3.5 parts by weight7. Dispersant As appropriate, the carbon nanotubes used are multi-walled carbon nanotubes # 900-1205 (diameter 60-100 nm) manufactured by SES Research.

Each raw material was mixed with the said composition, and the coating composition was obtained. This was applied to a 125 μm-thick PET film (single-sided easy-adhesive PET film A-4100 manufactured by Toyobo Co., Ltd.) at a thickness of 10 μm, and irradiated with ultraviolet rays using an H bulb 400 mJ / cm ^{2 to} be cured.

Examples 1-5, Comparative Example 1
The same energy beam curable antistatic hard coat resin composition was prepared by changing the amount of carbon nanotubes to the amount shown in Table 1, and the coating and curing on the base film was carried out in the same manner as in Example 1. went.
Further, as Comparative Example 1, an energy-curable curable antistatic hard coat resin composition containing no carbon nanotubes was prepared, and coated and cured on a base film in the same manner as in Example 1.

Comparative Example 2
An energy ray curable antistatic hard coat resin composition was prepared in the same manner as in Example 3 except that a multi-wall carbon nanotube manufactured by SES Research was used as the carbon nanotube, and the length was less than 5 μm. Application and curing on the substrate film were carried out in the same manner as in Example 1.

These energy beam curable antistatic hard coat resin compositions and antistatic treatment films were evaluated based on the following evaluation criteria. The results are shown in Table 1 and FIGS.

The transmittance at 550 nm of the antistatic treatment film was measured using a Hitachi 3900H spectrophotometer.

About the surface resistance value of the coating film of the test piece when the surface resistance value of the antistatic film is 20 ° C. and the relative humidity is 60%, the high and low efficiency meters Hiresta-UX and MCP-HT800 manufactured by Mitsubishi Chemical Analytical are used for the high resistivity meter. Measurement electrode box MCP-JB-04 was mounted and applied voltage was measured at 1000 (V).

Length of carbon nanotube The surface of the obtained film was photographed with a digital microscope VHX-5000 manufactured by Keyence, and the maximum diameter of all the carbon nanotubes present in the image was further measured with image analysis software. Was calculated. The maximum diameter of 20 particles was calculated, the average value was calculated, and this was taken as the average length of the carbon nanotubes. The film of Example 1 was measured and the average length was 7.5 μm. When the same measurement was performed on the film of Comparative Example 2, it was 4.4 μm.

From the results shown in Table 1, the antistatic layer formed using the energy ray-curable antistatic hard coat resin composition of the present invention is excellent in transparency and sufficient in physical properties such as antistatic ability and hard coat properties. I was able to get a good nature. On the other hand, in Comparative Example 2, no improvement in chargeability was observed.

In FIG. 1, the relationship between the compounding quantity of a carbon nanotube and 550 nm light transmittance was shown. FIG. 2 shows the relationship between the compounding amount of the carbon nanotubes and the surface resistance value. Also from these figures, it is clear that the energy beam curable antistatic hard coat resin composition of the present invention has the above-described excellent performance.

The energy ray curable antistatic hard coat resin composition of the present invention has high transparency and can impart excellent antistatic performance while having little influence on the physical properties of the hard coat resin. It is.

Claims (4)

Containing carbon nanotubes having an average length of 5 μm or more and an energy ray curable resin,
The carbon nanotube has a concentration in the nonvolatile content of the composition of 0.03% by weight or more and less than 0.15% by weight, an energy ray curable antistatic hard coat resin composition. 2. The energy beam curable antistatic hard coat resin composition according to claim 1, which is solvent-free. An antistatic treatment film comprising a layer made of a resin obtained by curing the energy ray-curable antistatic hard coat resin composition according to claim 1 or 2 on an base material film. A step (1) of applying the energy ray curable antistatic hard coat resin composition according to claim 1 or 2 on a base film and a step (2) of carrying out energy ray curing.
A method for producing an antistatic film, comprising: