JP4670745B2 - Antistatic composition, antistatic layer and antistatic film - Google Patents

Description

  The present invention relates to an antistatic composition used for a housing of an electric product, a display device such as a display, precision electronic parts, flooring materials, various films, sheets and the like. The present invention also relates to an antistatic layer formed from such an antistatic composition and an antistatic film comprising the antistatic layer.

  Products that use plastic film as a substrate have high volume resistivity, so they easily carry static electricity on the contact surface due to friction, etc., and they do not leak, which can cause problems due to dust adsorption and static electricity. Arise. For example, various display devices such as liquid crystal displays, CRTs, and plasma displays use a transparent plastic film that has been hard-coated to protect the surface. Further, due to troubles in the process due to static electricity, a decrease in productivity is a problem. Moreover, when it is actually used as a display, there is a problem that the visibility is remarkably lowered due to adsorption of dust on the surface.

  In order to improve such problems and impart antistatic performance, it has been studied to form an antistatic hard coat on a plastic film.

  For example, attempts have been made to form an antistatic hard coat by applying an antistatic composition containing a quaternary ammonium base-containing polymer to a plastic film.

  However, the quaternary ammonium base-containing polymer has poor compatibility in the antistatic composition, and there is a problem in that the antistatic hard coat formed has poor transparency and scratch resistance.

In order to solve such a problem, for example, Patent Document 1 defines the type of solvent and the molecular weight of the quaternary ammonium base-containing polymer, but the adhesion to the base film, the antistatic property, and the scratch resistance. And transparency is not enough.
JP 2003-268316 A

An object of the present invention is to provide an antistatic composition in which the quaternary ammonium base-containing polymer has good compatibility.
The present invention also provides an antistatic composition excellent in compatibility with such a quaternary ammonium base-containing polymer, and is antistatic, scratch-resistant and transparent even under an environment exposed to ultraviolet rays or under a high temperature and high humidity load. It is an object of the present invention to provide an antistatic layer excellent in properties and adhesion to a substrate and an antistatic film comprising such an antistatic layer.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that a compound containing a (meth) acryloyl group, a quaternary ammonium base-containing polymer, and N-vinylformamide as an antistatic composition. The present inventors have found that the above-mentioned problems can be solved by using.

That is, the gist of the present invention is as follows.
An antistatic composition comprising a compound having a (meth) acryloyl group, a quaternary ammonium base-containing polymer, and N-vinylformamide ;
An antistatic layer formed by applying the antistatic composition on a substrate;
And
An antistatic film having a substrate and the antistatic layer,
Exist.

  The antistatic composition of the present invention has good compatibility with the quaternary ammonium base-containing polymer. For this reason, the antistatic layer of the present invention formed using such an antistatic composition has antistatic properties, scratch resistance, and transparency even under ultraviolet light exposure or high temperature / high humidity load environments. Excellent and excellent adhesion to the substrate.

  Embodiments of the present invention will be described in detail below, but the description of the constituent elements described below is an example (representative example) of an embodiment of the present invention, and the present invention does not exceed the gist thereof. It is not specified in the contents.

[Antistatic composition]
The antistatic composition of the present invention contains a compound having a (meth) acryloyl group, a quaternary ammonium base-containing polymer, and N-vinylformamide .

(1) Compound having (meth) acryloyl group The compound having (meth) acryloyl group used in the present invention means a compound having at least one (meth) acryloyl group in the molecule, and even if it is a monomer, it is an oligomer. It may be. In the present invention, the acryloyl group and the methacryloyl group are collectively referred to as a (meth) acryloyl group. That is, the compound having a (meth) acryloyl group may be a compound having only an acryloyl group, a compound having only a methacryloyl group, or a compound having an acryloyl group and a methacryloyl group. May be. The same applies to (meth) acrylates and (meth) acrylic esters described below.

  As a compound which has the (meth) acryloyl group of this invention, the monomer or oligomer of the polyfunctional (meth) acrylate and monofunctional (meth) acrylate described below is mentioned, for example.

  Polyfunctional (meth) acrylates include pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate, neopentyl glycol di ( (Meth) acrylate, diethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, 1,6-hexanediol di (meth) acrylate, tripropylene glycol di (meth) acrylate, tricyclodecane dimethanol di (meth) Examples include acrylate, epoxy (meth) acrylate, urethane (meth) acrylate, and the like.

  Monofunctional (meth) acrylates include methyl (meth) acrylate, ethyl (meth) acrylate, acrylonitrile, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, Phenoxyethyl (meth) acrylate, 2-phenoxy-2-hydroxypropyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 3-chloro-2-hydroxypropyl (meth) acrylate, glycerol mono (meta) ) Acrylate, glycidyl (meth) acrylate, lauryl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, tricyclodecanyl (meth) acrylate, disic Pentenyl (meth) acrylate, n-butyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, Dodecyl (meth) acrylate, n-stearyl (meth) acrylate, benzyl (meth) acrylate, phenol ethylene oxide modified (n = 2) (meth) acrylate, nonylphenol propylene oxide modified (n = 2.5) (meth) acrylate, Half (meth) acrylate, furfuryl (meta) of phthalic acid derivatives such as 2- (meth) acryloyloxyethyl acid phosphate and 2- (meth) acryloyloxy-2-hydroxypropyl phthalate Acrylate, carbitol (meth) acrylate, benzyl (meth) acrylate, butoxyethyl (meth) acrylate, allyl (meth) acrylate 2-acryloyloxyethyl acid phosphate mono ester.

  These compounds having a (meth) acryloyl group may be used singly or in combination of two or more.

  The content of the compound having a (meth) acryloyl group is usually 30 parts by weight or more, preferably 50 parts by weight or more, usually 98 parts by weight or less, preferably 95 parts by weight with respect to 100 parts by weight of the solid content of the antistatic composition. Or less. When the content of the compound having a (meth) acryloyl group is less than this lower limit, the scratch resistance of the coating film is insufficient, and when it exceeds the upper limit, the concentration of the quaternary ammonium base-containing polymer is lowered and the antistatic property is lowered. To do.

(2) Quaternary ammonium base-containing polymer The quaternary ammonium base-containing polymer used in the present invention is a polymer having one or more quaternary ammonium bases. The quaternary ammonium base-containing polymer can be obtained, for example, by copolymerization of a monomer having an unsaturated group containing a quaternary ammonium base and a compound having another unsaturated group (for example, a monomer or an oligomer).

As a specific example of such a quaternary ammonium base-containing polymer,
(A) A copolymer of a monomer having a polymerizable group containing a quaternary ammonium base and (meth) acrylic acid ester.
(B) A copolymer of an oligomer having a polymerizable group containing a quaternary ammonium base and a (meth) acrylic acid ester.
(C) a copolymer of a quaternary ammonium base-containing (meth) acrylic acid ester and another (meth) acrylic acid ester and / or a styrene monomer (d) a quaternary ammonium base-containing (meth) acrylic acid ester , Copolymers with other (meth) acrylic esters and / or styrenic oligomers (e) quaternary ammonium base-containing (meth) acrylic esters, other (meth) acrylic esters and / or other ( A copolymer with a (meth) acrylic acid ester oligomer etc. can be illustrated.

  Examples of the monomer having a polymerizable group containing a quaternary ammonium base include compounds having an ester bond such as a quaternary salt of dimethylaminoethyl (meth) acrylate, and amides such as a quaternary salt of diethylaminoethyl (meth) acrylamide. Examples thereof include a compound having a bond.

  The molecular weight of the quaternary ammonium base-containing polymer is a number average weight molecular weight determined by a polystyrene standard using gel permeation chromatography (GPC), and is usually 5000 or more, preferably 7000 or more, usually 300000 or less, preferably 500000 or less. is there. If the number average weight molecular weight of the quaternary ammonium base-containing polymer is less than this lower limit, bleeding to the surface of the cured coating film tends to occur, such being undesirable. On the other hand, when the upper limit is exceeded, the compatibility in the antistatic composition may be lowered, which is not preferable.

  One of these quaternary ammonium base-containing polymers may be used alone, or two or more thereof may be mixed and used.

  Content of a quaternary ammonium base containing polymer is 1-50 weight part normally in 100 weight part of solid content of an antistatic composition, Preferably it is 1-30 weight part. If the content of the quaternary ammonium base-containing polymer is too small, sufficient antistatic performance due to the quaternary ammonium base-containing polymer cannot be obtained, and if it exceeds this upper limit, the transparency of the cured coating film may be lowered. Is not preferable.

(3) N-vinylformamide
The content of N-vinylformamide varies depending on the desired antistatic property, scratch resistance, and adhesion, but is usually 50 parts by weight or less, preferably 40 parts by weight with respect to 100 parts by weight of the solid content of the antistatic composition. Hereinafter, it is particularly preferably 30 parts by weight or less, usually 1 part by weight or more, preferably 5 parts by weight or more.

By adding N-vinylformamide to the composition, the compatibility of the quaternary ammonium base-containing polymer is improved, and the adhesion to the substrate is improved. As described above, N-vinylformamide The effect is further improved by making the amount of 50 parts by weight or less in 100 parts by weight of the solid content of the composition. However, when the content of N-vinylformamide is too large, the content of other components is relatively reduced, and thus the antistatic performance and the like may be deteriorated.

(4) Polymerization initiator The antistatic composition of the present invention is usually cured by irradiation with active energy rays such as gamma rays, electron rays or ultraviolet rays. When curing using ultraviolet rays, it is preferable to add a polymerization initiator to the antistatic composition of the present invention. As the polymerization initiator, any known polymerization initiator such as a benzophenone initiator, a diketone initiator, an acetophenone initiator, a benzoin initiator, a thioxanthone initiator, or a quinone initiator may be used.

  Usually, the polymerization initiator is used in the range of 1.0 to 10.0 parts by weight with respect to 100 parts by weight of the solid content of the antistatic composition.

(5) Solvent The antistatic composition of the present invention may contain a solvent, and can contain any amount of solvent so that the antistatic layer obtained after curing has a desired thickness.

Although it does not specifically limit as a solvent, For example, alcohols, such as ketone solvents, such as methyl isobutyl ketone, methyl ethyl ketone, cyclohexanone, and methyl amyl ketone, methanol, ethanol, t-butanol, isopropanol, n-butanol, propylene glycol monomethyl ether System solvents and the like.
These solvents may be used alone or in combination of two or more solvents.

  The content of the solvent is preferably 1 part by weight or more, more preferably 20 parts by weight or more, and particularly preferably 40 parts by weight or more with respect to 100 parts by weight of the solid content of the antistatic composition. Further, it is preferably 10,000 parts by weight or less, more preferably 5000 parts by weight or less, and particularly preferably 1000 parts by weight or less.

(6) Other components It is also possible to add a silicone type or fluorine type leveling agent to the antistatic composition of the present invention. Further, by adding fine particles to the antistatic composition of the present invention, fine irregularities are formed on the surface of the hard coat layer, so that antiglare property can also be imparted. In this case, examples of the fine particles include inorganic fine particles such as silica, and organic fine particles such as polymethyl (meth) acrylate.
In addition to the above, the antistatic composition of the present invention may contain other additives as necessary.

[Antistatic layer and antistatic film]
Although the antistatic composition of the present invention is not particularly limited, it is usually applied onto a substrate using a known coating apparatus, and then the solvent is removed and dried, and active energy rays are irradiated. It is used for the purpose of forming an antistatic layer by curing.

As a known coating apparatus, a coating apparatus such as a micro gravure coater, a gravure coater, a Meyer bar coater, or a die coater can be used.
The substrate is not particularly limited, and examples thereof include resin films and resin substrates such as polycarbonate resins, polyester resins, acrylic resins, triacetyl cellulose resins, norbornene resins. .

  The antistatic layer can usually be used as an antistatic film having an antistatic layer on a substrate made of the resin film as described above. When used as an antistatic film, the antistatic layer may be formed directly on the base material, or may be formed on the base material via another layer.

  The antistatic layer thus obtained is excellent in antistatic properties, scratch resistance, transparency, and substrate adhesion. In addition, it is excellent in antistatic property, scratch resistance and transparency even under the environment of UV exposure, high temperature and high humidity load, and excellent adhesion to the substrate.

  The antistatic layer or antistatic film of the present invention is useful as a protective film such as a hard coat layer of a display element such as a housing of an electric product or a display, a precision electronic component, a flooring material, various films, and a sheet.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to a following example, unless the summary is exceeded.

(Synthesis Example 1)
A flask equipped with a stirring blade, a dropping funnel and a gas inlet was sufficiently substituted with dry nitrogen, and then 32 g of n-butyl alcohol and 1 g of metallic sodium were charged and stirred to dissolve the metallic sodium. Next, the flask was immersed in an oil bath at 40 ° C., and 500 g of ε-caprolactone was dropped from the dropping funnel while stirring. After 1 hour, stirring was stopped and the contents of the flask were taken out and dissolved in 5 L of chloroform. The resulting solution was poured into 5 L of deionized water, washed and the chloroform layer was separated. This washing was repeated once more, and the solvent was distilled off from the chloroform solution under reduced pressure to obtain a colorless and transparent polyester alcohol. The hydroxyl value of this polyester alcohol was 56.1 mg-KOH / g.

Subsequently, to the reactor equipped with a stirring blade and a reflux condenser, 102.3 g of the polyester alcohol synthesized above, 20.7 g of m-isopropenyl-α, α′-dimethylbenzyl isocyanate, and 0.05 g of dibutyltin dioctoate were added. Was heated to 80 ° C. and reacted for 6 hours. From the infrared spectrum of the product and the measurement result of ¹ H-NMR, it was confirmed that a polyester macromonomer was obtained.

  In a flask equipped with a stirring blade, a reflux condenser, and a gas inlet, 72.7 g of the polyester macromonomer synthesized above, 121.5 g of methacryloyloxyethyltrimethylammonium chloride, 48.8 g of cyclohexyl methacrylate, azobisisobutyronitrile 1.2 g, 400 g of isopropyl alcohol, and 170 g of methyl ethyl ketone were charged and polymerized at 70 ° C. for 8 hours under a nitrogen stream. After completion of the polymerization, the reaction solution was poured into hexane to precipitate the product and then dried. The number average molecular weight of the obtained quaternary ammonium base-containing polymer was 28,000, and the yield was 94%.

(Synthesis Example 2)
In a flask equipped with a stirring blade, a reflux condenser, and a gas inlet, 18.0 g of octyl polyethylene glycol polypropylene glycol methacrylate (trade name: “Blemmer 50POEP-800B” manufactured by NOF Corporation), 35.0 g of methacryloyloxyethyltrimethylammonium chloride Then, 14.0 g of cyclohexyl methacrylate, 0.3 g of azobisisobutyronitrile, 100 g of isopropyl alcohol, and 40 g of methyl ethyl ketone were charged and polymerized at 70 ° C. for 2 hours in a nitrogen stream. After completion of the polymerization, the reaction solution was poured into hexane to precipitate the product and then dried. The number average molecular weight of the obtained quaternary ammonium base-containing polymer was 38,000, and the yield was 85%.

Example 1
40 parts by weight of dipentaerythritol hexaacrylate (product name: “NK ester A-DPH” manufactured by Shin-Nakamura Chemical Co., Ltd.), 25 parts by weight of dipentaerythritol pentaacrylate / hexaacrylate (product name: “M-403” manufactured by Toagosei Co., Ltd.) 20 parts by weight of phenoxyethyl acrylate (product name: “light acrylate PO-A” manufactured by Kyoeisha Chemical), 10 parts by weight of N-vinylformamide (product name: “beam set 770” manufactured by Arakawa Chemical Industries), and synthesis example 1 A composition comprising 5 parts by weight of the quaternary ammonium base-containing polymer and 3 parts by weight of Irgacure 907 (manufactured by Ciba Specialty Chemicals) as a photopolymerization initiator was obtained as methyl ethyl ketone / isopropyl alcohol / methyl isobutyl ketone = 75/20/5 ( To 60 wt% solids with a mixed solvent of The antistatic composition of the present invention was prepared by diluting.

  This composition was applied on a triacetyl cellulose film (product name: “TAC PHAN” manufactured by Lo Ho Hitec Film Co., Ltd.) having a film thickness of about 80 μm, dried after removing the solvent, and then irradiated with ultraviolet rays to form a film having a thickness of 10 μm. An antistatic layer was obtained.

The film having the antistatic layer (antistatic film) was evaluated by the following evaluation method, and the results are shown in Table 1. In addition, (1)-(4) evaluated the antistatic layer side surface.
(1) Surface resistance value: According to JIS K6911.
(2) Substrate adhesion: According to JIS K5400 cross-cut tape method (gap spacing 1 mm).
(3) Pencil hardness: According to JIS K5400.
(4) Scratch resistance: Using steel wool # 0000, the appearance was visually evaluated after 10 reciprocal scratches at a load of 1000 g.
(5) Transparency: The haze value (Hz) was determined according to JIS K7136, and the total light transmittance (TT) was determined according to JIS K7361-1.

Next, after performing the following durability tests A or B using this film, the same evaluation as the above (1), (2) and (5) was performed, and the results are shown in Table 2.
Test A (high temperature / high humidity load): left in an atmosphere of 85 ° C. and 85% RH for 100 hours.
Test B (UV exposure): 500 using a sunshine carbon arc lamp type light resistance tester
Time tested.
As is clear from Tables 1 and 2, good results were obtained in all evaluations.

(Example 2)
50 parts by weight of dipentaerythritol hexaacrylate (product name: “NK Ester A-DPH” manufactured by Shin-Nakamura Chemical Co., Ltd.), 25 parts by weight of dipentaerythritol pentaacrylate / hexaacrylate (product name: “M-403” manufactured by Toagosei Co., Ltd.) 10 parts by weight of phenoxyethyl acrylate (product name: “light acrylate PO-A” manufactured by Kyoeisha Chemical), 10 parts by weight of N-vinylformamide (product name: “beam set 770” manufactured by Arakawa Chemical Industries), and synthesis example 2 A composition comprising 5 parts by weight of the quaternary ammonium base-containing polymer and 3 parts by weight of Irgacure 907 (manufactured by Ciba Specialty Chemicals) as a photopolymerization initiator was obtained as methyl ethyl ketone / isopropyl alcohol / methyl isobutyl ketone = 75/20/5 ( To 60 wt% solids with a mixed solvent of An antistatic film was obtained in the same manner as in Example 1 except that the antistatic composition of the present invention was prepared by dilution, and evaluation was performed in the same manner. The evaluation results are shown in Tables 1 and 2.
As is clear from Tables 1 and 2, good results were obtained in all evaluations.

(Example 3)
Water content: 38 parts by weight of isophorone diisocyanate, 15 parts by weight of tris- (2-hydroxyethyl) isocyanurate, 52 parts by weight of pentaerythritol triacrylate, 0.006 parts by weight of dibutyltin dioctoate, 0.1 part by weight of 4-methoxyphenol A urethane acrylate was synthesized by reacting at 70 ° C. for 8 hours under 0.1% dry air.

20 parts by weight of the above urethane acrylate, 40 parts by weight of dipentaerythritol hexaacrylate (product name: “NK Ester A-DPH” manufactured by Shin-Nakamura Chemical Co., Ltd.), dipentaerythritol penta / hexaacrylate (product name: “M-403” Toa) 25 parts by weight of synthetic), 10 parts by weight of N-vinylformamide (product name: “beam set 770” manufactured by Arakawa Chemical Industries), and 5 parts by weight of the quaternary ammonium base-containing polymer synthesized in Synthesis Example 1, a photopolymerization initiator A composition comprising 3 parts by weight of Irgacure 907 (manufactured by Ciba Specialty Chemicals) was diluted to a solid content of 60% by weight with a mixed solvent of methyl ethyl ketone / isopropyl alcohol / methyl isobutyl ketone = 75/20/5 (part by weight ratio). As in Example 1, except that the antistatic composition of the present invention was prepared. Thus, an antistatic film was obtained and evaluated in the same manner, and the evaluation results are shown in Tables 1 and 2.
As is clear from Tables 1 and 2, good results were obtained in all evaluations.

Example 4
An antistatic film was obtained in the same manner as in Example 1 except that a polycarbonate resin film was used in place of the triacetyl cellulose film. Evaluation was performed in the same manner, and the evaluation results are shown in Tables 1 and 2.
As is clear from Tables 1 and 2, good results were obtained in all evaluations.

(Comparative Example 1)
40 parts by weight of dipentaerythritol hexaacrylate (product name: “NK Ester A-DPH” manufactured by Shin-Nakamura Chemical Co., Ltd.), 35 parts by weight of dipentaerythritol pentaacrylate / hexaacrylate (product name: “M-403” manufactured by Toagosei Co., Ltd.) 20 parts by weight of phenoxyethyl acrylate (product name: “light acrylate PO-A” manufactured by Kyoeisha Chemical Co., Ltd.), 5 parts by weight of the quaternary ammonium base-containing polymer synthesized in Synthesis Example 1, and Irgacure 907 (Ciba Specialty) as a photopolymerization initiator A composition comprising 3 parts by weight of tea chemicals) was diluted to a solid content of 60% by weight with a mixed solvent of methyl ethyl ketone / isopropyl alcohol / methyl isobutyl ketone = 75/20/5 (parts by weight) to obtain an antistatic composition. An antistatic film was obtained in the same manner as in Example 1 except that it was prepared. The evaluation was performed in the same manner, and the evaluation results are shown in Tables 1 and 2.
As is clear from Tables 1 and 2, the antistatic film formed from the antistatic composition containing no N-vinylformamide was a film having low transparency and low substrate adhesion to the antistatic layer.

Claims (6)

An antistatic composition comprising a compound having a (meth) acryloyl group, a quaternary ammonium base-containing polymer, and N-vinylformamide . The quaternary ammonium base-containing polymer is
A quaternary ammonium base-containing (meth) acrylic acid ester;
The antistatic composition according to claim 1, which is a copolymer with a (meth) acrylic acid ester and / or a styrene-based oligomer. The quaternary ammonium base-containing polymer is
A quaternary ammonium base-containing (meth) acrylic acid ester;
The antistatic composition according to claim 1, which is a copolymer with (meth) acrylic acid ester and / or other (meth) acrylic acid ester oligomer. The charging according to any one of claims 1 to 3 , wherein the content of the N-vinylformamide is 50 parts by weight or less with respect to 100 parts by weight of the solid content in the composition. Prevention composition. An antistatic layer formed by applying the antistatic composition according to any one of claims 1 to 4 on a substrate. An antistatic film comprising the base material and the antistatic layer according to claim 5 .