JP2003155366A - Antistatic film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an antistatic polyester film having excellent antistatic properties, resistance to back surface transferring, and resistance to scratch. SOLUTION: This antistatic film has an antistatic coating which is formed by applying a coating liquid containing a polymeric antistatic agent (A) to at least one surface of a thermoplastic resin film, then drying and drawing the film so as to form the antistatic coating on the surface, wherein the polymeric antistatic agent (A) contains repeating units having a structure expressed by general formula (I) (R<1> is H or methyl; R<2> is a 1-5C aliphatic hydrocarbon residue, R<3> and R<4> are each a 1-4C aliphatic hydrocarbon residue; R<5> is a 1-12C aliphatic hydrocarbon residue, an aromatic hydrocarbon residue or a combined residue thereof; X is a reactive groups on which a cross-linkage is formed; and Y<-> is an anionic compound) as an essential component.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antistatic film, and more particularly to a packaging material, an electronic material, a graphic material, a plate-making film, an OHP film, which is excellent in antistatic property, back surface transfer property, transparency and heat resistance. The present invention relates to an antistatic film useful for magnetic recording materials (for example, magnetic tapes such as audio tapes and video tapes, magnetic disks such as flexible disks, and magnetic cards).

[0002]

2. Description of the Related Art Thermoplastic resin films are used for packaging materials,
Electronic materials, graphic materials, plate-making films, O
It is widely used as a base film for HP films, magnetic recording materials, etc. However, static electricity is easily generated as a common problem with plastic films, and various static electricity is generated in the film forming process, processing process, and when the product is used. There is a drawback that troubles are likely to occur. For example, thick white polyester film is used for magnetic cards such as telephone cards and prepaid cards, but its manufacturing process, processing process, and antistatic property as the final product are difficult, and the film surface has antistatic property. Various methods for forming a coating film have been proposed and put into practical use. As the antistatic agent to be contained in the antistatic coating film, a low molecular weight type and a high molecular weight type are conventionally known, but each has its own advantages and disadvantages. Therefore, the antistatic agent is used properly according to its characteristics.

For example, as a low molecular type antistatic agent,
Long-chain alkyl compound having sulfonate group
0-141525) and the like, a surfactant type anionic antistatic agent is known, and as a high molecular type antistatic agent, a sulfonate-modified polystyrene as an anionic polymer (JP-A- 61-204240), quaternary ammonium salt-containing acryl (Japanese Patent Application Laid-Open No. 52-136274), and the like are known as cationic polymers. However, in the antistatic coating film using a low molecular type antistatic agent, a problem caused by a part of the antistatic agent moving in the coating film and accumulating at the interface and moving to the opposite surface of the film or the like, There is a problem that the antistatic property deteriorates with time. On the other hand, in the case of antistatic coating film using polymer type antistatic agent, it is necessary to add a large amount of antistatic agent in order to exhibit good antistatic property, or antistatic property with thick film thickness. It is not economical because it is necessary to form a coating film. Furthermore, there are drawbacks such as easy peeling of the coating film,
Stretching and heat treatment at a high temperature have drawbacks such as impairing transparency and antistatic properties of the film, and therefore their solution is desired.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the prior art and to provide an antistatic polyester film excellent in antistatic property, back surface transfer property and abrasion resistance. .

[0005]

As a result of intensive studies in view of the above problems, the present inventor has found that the above problems can be easily solved by using a specific antistatic agent, and completes the present invention. Came to. That is, the gist of the present invention is to apply a coating liquid containing a polymeric antistatic agent (A) containing a repeating unit of the structure represented by the following general formula (I) as an essential component to at least one surface of a thermoplastic resin film. , An antistatic film having an antistatic coating film formed by drying and stretching.

[Chemical 2] (In the above formula, R ¹ is H or a methyl group, and R ² has 1 carbon atom.
~ 5 aliphatic hydrocarbon group, R ³ and R ⁴ are each an aliphatic hydrocarbon group having 1 to 4 carbon atoms, and R ⁵ is 1 to 1 carbon atoms.
2 is an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a composite group thereof, X is a reactive group serving as a crosslinking point, and Y ⁻ is an anionic compound)

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The thermoplastic resin film of the present invention includes, as its material, a polyolefin film typified by polyethylene and polypropylene, a polyester film typified by polyethylene terephthalate, a polyamide film typified by nylon, and a polystyrene film. Among them, polyester films and polyamide films having excellent mechanical properties, heat resistance, transparency and the like are preferable, and particularly, polyethylene terephthalate / polyethylene naphthalate is preferable in terms of mechanical strength. These thermoplastic resin films,
It can be produced by a conventional method. Hereinafter, a polyester film will be described as a typical example, but the present invention is not limited thereto.

In the present invention, the polyester constituting the polyester film is, for example, a linear polyester composed of a dicarboxylic acid component and a glycol component. Examples of the dicarboxylic acid component include terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, hexahydroterephthalic acid, 4,4'-diphenyldicarboxylic acid, adipic acid, sebacic acid, dodecanedicarboxylic acid and the like. Particularly, terephthalic acid and 2,6-naphthalenedicarboxylic acid are preferable from the viewpoint of the mechanical properties of the film.

As the glycol component, ethylene glycol, diethylene glycol, propylene glycol,
1,3-propanediol, 1,4-butanediol,
Neopentyl glycol, 1,6-hexanediol,
Examples thereof include cyclohexanedimethanol and polyethylene glycol. In particular, ethylene glycol is preferable from the viewpoint of film rigidity. The above polyester is the third
As the component, a copolyester obtained by copolymerizing the above dicarboxylic acid component or glycol component may be used, and a trifunctional or higher polyvalent carboxylic acid component or polyol component may be used in a range in which the resulting polyester is substantially linear (for example, It may be a polyester copolymerized in a small amount of 5 mol% or less).

The thermoplastic resin film includes inorganic fillers such as silicon oxide, aluminum oxide, magnesium oxide, calcium carbonate, kaolin and talc, crosslinked silicone resin, crosslinked polystyrene resin, crosslinked acrylic resin, urea resin and melamine resin. Organic fillers made of heat resistant polymers such as, titanium oxide, hiding pigments such as barium sulfate, color pigments, polyethylene, polypropylene, ethylene-propylene copolymers, other resins such as olefinic ionomers, stabilizers, Antioxidants, ultraviolet absorbers, optical brighteners and the like can be added as necessary. The thickness of the thermoplastic resin film of the present invention is not particularly limited and is appropriately selected depending on the application,
In many cases, it is used in the range of 2 μm or more, and further in the range of 10 to 500 μm. This thickness is less than 2 μm, and 500 μ
If it exceeds m, the film-forming property tends to be poor.

In the present invention, the base film is preferably a biaxially stretched film, and the antistatic coating film provided on at least one surface of the thermoplastic resin film of the present invention is
The coating liquid containing the antistatic agent (A) is applied, dried and stretched. By being stretched, the adhesion of the layer to the base material film and the uniformity of the layer are improved, and an excellent antistatic effect can be exhibited. The antistatic agent (A) in the present invention is a compound whose main component is a repeating unit having a structure represented by the following formula (I).

[0011]

[Chemical 3] (In the above formula, R ¹ is H or a methyl group, and R ² has 1 carbon atom.
~ 5 aliphatic hydrocarbon group, R ³ and R ⁴ are each an aliphatic hydrocarbon group having 1 to 4 carbon atoms, and R ⁵ is 1 to 1 carbon atoms.
2 is an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a composite group thereof, X is a reactive group serving as a crosslinking point, and Y ⁻ is an anionic compound)

In the above formula, the position of the phenylene group substituent is
Although not particularly limited, R ²And the position where
However, a p-substitution is preferable. The reactive group of X is
Although not limited, preferably a hydroxyl group and an amino group.
Group, amide group, carboxylic acid group, acid anhydride group, glycidyl
Groups, oxazoline groups, methylol groups, silanol groups, etc.
Can be mentioned. Y in the antistatic agent (A)^-Is anionic
The compound is not particularly limited, but is preferably
Or halogen ion, mono- or poly-halogenated alkyl
Kill ion, nitrate ion, sulfate ion
Ion, alkyl sulfate ion, sulfonate ion
Alternatively, it can be appropriately selected from alkyl sulfonate ions.
However, preferably, chlorine ion, methanesulfonate ion
Ion, ethane sulfonate ion, and nitrate ion are selected.
It

The antistatic agent (A) used in the present invention can be produced by a conventional method. The antistatic agent may be a homopolymer of the component of general formula (I) or a copolymer with another resin component. As this copolymerization component,
Addition-polymerizable monomers having unsaturated double bonds known as acrylic monomers and vinyl monomers are preferable.

Examples of acrylic monomers and vinyl monomers are methyl acrylate, methyl methacrylate, ethyl methacrylate, ethyl acrylate, n-propyl methacrylate, n-propyl acrylate, isopropyl methacrylate, isopropyl acrylate, and n.
-Butyl methacrylate, n-butyl acrylate, isobutyl methacrylate, isobutyl acrylate, t
-Butyl methacrylate, t-butyl acrylate, 2
-Acrylic monomer group such as ethylhexyl methacrylate, 2-ethylhexyl acrylate, lauryl methacrylate, lauryl acrylate, stearyl methacrylate, stearyl acrylate, cyclohexyl methacrylate, cyclohexyl acrylate, phenyl methacrylate, phenyl acrylate, N, N-dimethylaminoethyl methacrylate, N, N-diethylaminoethyl methacrylate, 2-aminoethyl methacrylate, 2-aminoethyl acrylate, 3-aminopropyl methacrylate, 3-aminopropyl acrylate, 2-aminobutyl methacrylate, 2-aminobutyl acrylate, N, N-dimethylaminoethyl vinyl ether , N, N-diethylaminoethyl vinyl ether, 2-aminoethyl Monomer groups having amino groups such as vinyl ether, 3-aminopropyl vinyl ether, 2-aminobutyl vinyl ether, and those obtained by methylating the above amino groups, polyethylene glycol monomethacrylate, polyethylene glycol monoacrylate, methoxy polyethylene glycol monomethacrylate, polypropylene Glycol monomethacrylate, polyethylene glycol monoacrylate, polyethylene glycol-polypropylene glycol monomethacrylate, polyethylene glycol-polytetramethylene glycol monomethacrylate, polyethylene glycol-polypropylene glycol monoacrylate,
Polypropylene glycol-polytetramethylene glycol monomethacrylate and other alkylene glycol side chain-containing monomer groups, styrene, α-methylstyrene, methyl vinyl ketone, butyl vinyl ether, vinyl chloride,
Vinylidene chloride, vinyl pyridine, vinyl pyrrolidone,
Vinyl acetate, acrylonitrile, methacrylonitrile,
Examples thereof include, but are not limited to, mono- or dialkyl esters of maleic acid and itaconic acid, and vinyl-based monomer groups such as alkoxysilanes having a vinyl group.

Further, the compound having the structure represented by the general formula (I) is homopolymerized or copolymerized with the above-mentioned addition-polymerizable monomer component in the presence of a resin component such as a polyester resin or a polyurethane resin described later in the graft polymerization. It is also possible to obtain a copolymer by such a method. Although the average molecular weight (number average molecular weight) of the antistatic agent (A) is arbitrary, it is 1000
˜300000, and more preferably 3000 to 100000. If this average molecular weight is less than 1000, the backside transferability of the antistatic agent (A) tends to deteriorate, and if the average molecular weight exceeds 300,000, the viscosity of the coating liquid becomes too high, making it difficult to uniformly coat the film. Tends to become.

The proportion of the copolymerization component represented by the general formula (I) in the antistatic agent (A) of the present invention is not particularly limited, but is preferably 10% by weight or more, more preferably 15% by weight. As described above, particularly preferably 20% by weight or more, and it is desirable to satisfy such conditions because the antistatic property is improved. In the antistatic coating film of the present invention, it is preferable to use the antistatic agent (A) and the binder resin (B) together in order to make the adhesion between the coating film and the thermoplastic resin film stronger. .

Examples of the binder resin (B) include acrylic resin, polyurethane resin, polyester resin, vinyl resin, polyolefin resin, epoxy resin, polyether resin, water-soluble resin, and the like. It is preferable to use one or more types of resins described above. In particular, it is preferable to use an acrylic resin, a polyurethane resin, or a polyester resin because the adhesion between the antistatic coating film and the polyester film becomes good. After the glass transition temperature of the binder resin (B), there is no particular limitation, but it is preferably 0 ° C. or higher, and more preferably 20 to 100 ° C.

Acrylic resins that can be used as the binder resin (B) are, for example, acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate,
Sodium acrylate, ammonium acrylate, 2-hydroxyethyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate,
Sodium methacrylate, ammonium methacrylate, 2-
Hydroxyethyl methacrylate, glycidyl methacrylate, acrylonitrile, acrylamide, methacrylamide, N-methylol methacrylamide, and the like can be exemplified by one or more acrylic monomers selected from these compounds, and synthesized by a conventional polycondensation reaction. Can be obtained by doing. These monomers are polymerized in combination with other unsaturated monomers such as styrene, vinyl acetate, vinyl chloride, vinylidene chloride, divinylbenzene, sodium styrenesulfonate, sodium vinylsulfonate and sodium methallylsulfonate. You can also

Unsaturation 2 containing acrylic monomer
The copolymer can also be obtained by a method such as graft polymerization in which an addition polymerizable monomer having a heavy bond is present in the presence of a resin component such as a polyester polyester resin or a polyurethane resin described later. The polyurethane resin that can be used as the binder resin (B) can be synthesized, for example, by an ordinary polymerization reaction using the following polyols, polyisocyanates, chain extenders and the like as raw materials.

Examples of the polyol include polyethers such as polyoxyethylene glycol, polyoxypropylene glycol, polyoxypropylene triol, polyoxytetramethylene glycol, polyethylene adipate, polyethylene-butylene adipate, polypropylene adipate, and polyhexylene. Examples include adipate, polyesters such as polycaprolactone, acrylic polyol, castor oil, and the like. Examples of the polyisocyanate include aromatic diisocyanates such as tolylene diisocyanate, phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate and 1,5-naphthalene diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, lysine diisocyanate, 4,4 Aliphatic diisocyanates such as ′ -dicyclohexylmethane diisocyanate and isophorone diisocyanate may be mentioned.

Examples of the chain extender or crosslinking agent include ethylene glycol, propylene glycol, butanediol, hexanediol, diethylene glycol, trimethylolpropane, glycerin, hydrazine, ethylenediamine, diethylenetriamine, 4,
4'-diaminodiphenylmethane, 4,4'-diaminodicyclohexylmethane, water and the like. A polyurethane obtained by appropriately selecting from these compounds and synthesizing by a conventional polymerization reaction can be used. The polyester resin that can be used as the binder resin (B) is, for example, a linear polyester having a dicarboxylic acid component and a glycol component as constituent components.

As the dicarboxylic acid component, terephthalic acid, isophthalic acid, phthalic acid, 2,6 naphthalenedicarboxylic acid, 4,4-diphenyldicarboxylic acid, 1,4
Examples thereof include cyclohexanedicarboxylic acid, adipic acid, sebacic acid, phenylindanedicarboxylic acid and dimer acid. Two or more kinds of these components can be used. In addition to these components, unsaturated polybasic acids such as maleic acid, fumaric acid, itaconic acid, etc. and p
Hydroxycarboxylic acids such as -hydroxybenzoic acid and p- (β-hydroxyethoxy) benzoic acid can be used in small proportions. The ratio of the unsaturated polybasic acid component and the hydroxycarboxylic acid component is at most 10 mol%, preferably 5 mol% or less.

As the glycol component, ethylene glycol, 1,4-butanediol, neopentyl glycol, diethylene glycol, dipropylene glycol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, xylylene glycol, dimethylol. Propionic acid, glycerin, trimethylolpropane,
Examples thereof include poly (ethyleneoxy) glycol, poly (tetramethyleneoxy) glycol, bisphenol A alkylene oxide adducts, hydrogenated bisphenol A alkylene oxide adducts, and the like. These can use 2 or more types. Among such polyol components, ethylene glycol, an ethylene oxide adduct of bisphenol A and a propylene oxide adduct, and 1,4-butanediol are preferable, and ethylene glycol and an ethylene oxide adduct of bisphenol A and a propylene oxide adduct are more preferable.

In order to facilitate aqueous liquefaction, the polyester resin may be copolymerized with a small amount of a compound having a sulfonate group or a compound having a carboxylate group, which is preferred. Examples of the compound having a sulfonate group include 5-Na sulfoisophthalic acid, 5-ammonium sulfoisophthalic acid, 4
-Na sulfoisophthalic acid, 4-methylammonium sulfoisophthalic acid, 2-Na sulfoisophthalic acid, 5-
K sulfoisophthalic acid, 4-K sulfoisophthalic acid, 2
Preferable examples include sulfonic acid alkali metal salt-based compounds such as -K sulfoisophthalic acid and Na sulfosuccinic acid, or sulfonic acid amine salt-based compounds.

Examples of the compound having a carboxylate group include trimellitic anhydride, trimellitic acid, pyromellitic anhydride, pyromellitic acid, trimesic acid, cyclobutanetetracarboxylic acid, dimethylolpropionic acid, and the like. Examples include monoalkali metal salts. After the copolymerization, the free carboxyl group is reacted with an alkali metal compound or an amine compound to form a carboxylate group. A polyester obtained by appropriately selecting one or more from these compounds and synthesizing them by a conventional polycondensation reaction can be used. The above-mentioned binder resin can be used in combination in the antistatic coating film of the present invention in order to adjust the adhesion between the coating film and the thermoplastic resin film.

The coating liquid for forming the antistatic coating film in the present invention has a solid content composition of 5 to 100% by weight of the antistatic agent (A) and 0 to 95% by weight of at least one binder resin (B). It is preferably an aqueous coating liquid containing the same. More preferably, it is an aqueous coating liquid containing a solid content composition of 10 to 90% by weight of the antistatic agent (A) and 10 to 90% by weight of at least one binder resin (B). Particularly preferably, if the proportion of the antistatic agent (A) is less than 5% by weight, the antistatic property may be insufficient.

The antistatic coating film of the present invention includes a thermosetting compound (C) such as a melamine compound and a resin, a compound and a resin having a blocked isocyanate group, an epoxy compound and an epoxy resin, an oxazoline compound and a resin, and an aziridine compound. , Methylolated or alkylolated urea compounds, acrylamide / polyamide compounds, polyamines, silane coupling agents, titanium coupling agents, zirco-aluminate coupling agents, metal chelates, organic acid anhydrides, organic peroxides. Oxide,
Examples thereof include heat- or photo-reactive vinyl compounds and photosensitive resins, but are not limited thereto. An optimum cross-linking agent can be selected according to X in the general formula (I), that is, a reactive group serving as a cross-linking point.

By using the thermosetting compound (C) together, the antistatic coating film of the present invention strengthens the adhesion between the coating film and the thermoplastic resin film, and the antistatic film has blocking resistance. Can be good.
The coating liquid for forming the antistatic coating film in the present invention is an aqueous coating liquid containing a solid content composition of 5 to 100% by weight of an antistatic agent (A) and 0 to 95% by weight of a thermosetting compound (C). Preferably there is. More preferably, it is an aqueous coating liquid containing 10 to 90% by weight of the antistatic agent (A) and 10 to 90% by weight of at least one binder resin (B), and particularly preferably, the antistatic agent. (A) 20
~ 90 wt%, at least one binder resin (B)
It is preferably an aqueous coating liquid containing a solid content composition of 10 to 80% by weight. If the proportion of the antistatic agent (A) is less than 5% by weight, the antistatic property may be insufficient.

In the antistatic coating film of the present invention, known additives such as heat stabilizers, oxidation stabilizers, weather stabilizers, ultraviolet absorbers and organic additives are added to the extent that the effects of the present invention are not impaired. Lubricants, organic and inorganic fine particles, surfactants,
Waxes and the like may be added. The contents of these components can be appropriately optimized and used. As the surfactant, for example, alkylene oxide homopolymer,
Nonionic surfactants such as alkylene oxide copolymers, aliphatic alcohol / alkylene oxide impenetrable substances, long chain aliphatic substituted phenol / alkylene oxide impenetrable substances, polyhydric alcohol fatty acid esters, long chain aliphatic amide alcohols, etc., quaternary ammonium Examples thereof include a cationic or anionic surfactant such as a compound having a salt, a compound having an alkylpyridinium salt, and a compound having a sulfonate. Particularly, a nonionic surfactant is used for adhesion between a coating film and a base film. And excellent anti-blocking effect of the antistatic film are preferable.

As the lubricant, inorganic particles (colloidal silica, alumina, etc.), organic particles (self-crosslinking styrene particles, self-crosslinking acrylic particles, melamine resin, benzoguanamine resin, silicone resin, fluorine resin, etc.) are used. Can be mentioned. The antistatic coating film of the present invention is preferably formed by coating as an aqueous coating liquid (water is used as a medium), but it may contain a small amount of an organic solvent for the purpose of helping the stability of the coating agent. Alternatively, it is also possible to form by applying a coating liquid containing an organic solvent. Examples of this organic solvent include methyl ethyl ketone, acetone, ethyl acetate, tetrahydrofuran, dioxane, cyclohexanone, n-hexane, toluene, xylene, methanol, ethanol, n-propanol, isopropanol and the like. These may be used alone or in combination of two or more.

The solid content concentration of the coating liquid used in the present invention is not particularly limited as long as it satisfies the dry coating film thickness described below, but it is preferably 0.1 to 50% by weight or more, and more preferably 0. It is preferably 5 to 30% by weight. If the concentration is less than 0.1% by weight, the antistatic performance may be poor, and if it exceeds 50% by weight, the coating appearance may be deteriorated and a practical coating speed may not be obtained. In the present invention, the coating liquid containing each of the above-mentioned components is applied to at least one surface of the thermoplastic resin film, and the film to be applied is preferably a film before crystal orientation is completed. As the film before this oriented crystal is completed, an unstretched film obtained by directly melting a thermoplastic resin into a film, and a uniaxially stretched film obtained by orienting the unstretched film in either the longitudinal direction or the transverse direction. , A film which has been stretched and oriented in a low-magnification direction in both the machine direction and the transverse direction (a biaxially stretched film before it is finally re-stretched in the machine direction and the transverse direction to complete the oriented crystallization) and the like. it can.

As a method for applying the coating liquid to the thermoplastic resin film, any known coating method can be applied. For example, a rod coating method, a roll coating method, a gravure coating method, a micro gravure coating method, a reverse coating method, a roll brush method, a spray coating method, an air knife coating method, an impregnation method and a curtain coating method may be applied individually or in combination. . The coating amount is not particularly limited, but the thickness of the final dry coating film is preferably 0.01 to 1 μm, more preferably 0.03 to 0.8 μm. If the thickness of the coating film is less than 0.01 μm, the antistatic property may be insufficient, while if it exceeds 1 μm,
Blocking resistance tends to decrease.

In the present invention, the coating solution is applied to the thermoplastic resin film and then dried, preferably stretched, but this step differs depending on the thermoplastic resin to be applied. For example, in the case of a polyester film, this drying is preferably performed at 90 to 130 ° C. for 2 to 20 seconds. This drying can also serve as a preheat treatment for the stretching treatment or a heat treatment during the stretching. The stretching treatment of the thermoplastic resin film is carried out at a temperature of 70 to 140 ° C. in the longitudinal direction of 2.5 to 6 times, in the transverse direction of 2.5 to 6 times, and in area ratio of 8 times or more, further 9 to
It is preferable to stretch 30 times. When re-stretching,
It is preferable to stretch at a draw ratio of 1.05 to 3 times (however, the area magnification is the same as above). The heat setting treatment after stretching is preferably performed at a temperature higher than the final stretching temperature and lower than the melting point for 1 to 30 seconds. For example, for a polyethylene terephthalate film, it is preferable to heat-fix at 170 to 240 ° C for 2 to 30 seconds.

The antistatic and easily adhesive polyester film thus obtained has, for example, a specific surface resistivity (temperature 23
(° C, humidity 50%) is usually 3 × 10 ¹³ Ω / □ or less, preferably 3 × 10 ¹² Ω / □ or less, more preferably 3 × 10
^{It is 10} Ω / □ or less, and is excellent in adhesiveness, antistatic property, blocking resistance, back surface transfer property, and abrasion resistance.

[0035]

EXAMPLES The present invention will now be described in detail with reference to examples, but the present invention is not limited to the following examples. The evaluation in the present invention was performed by the following method.

(1) Surface resistivity (antistatic property) The surface resistivity of the sample film was measured using a high resistance meter: 4329A (trade name) and a measuring electrode: 16008A (trade name) manufactured by Hewlett Packard. Temperature 23
The surface specific resistance Ω / □ was measured at an applied voltage of 100 V after 1 minute of humidity conditioning at a temperature of 50 ° C. and a measured humidity of 50%. ◎: 3 × 10 ¹⁰ Ω / □ or less ○: 3 × 10 ¹² Ω / □ or less △: 3 × 10 ¹³ Ω / □ or less ×: 3 × 10 ¹³ Ω / □ or more

(2) Overlay the coated surface of the backside transferable sample film with the uncoated film, and
Apply a load of 0 kg / cm ² at 23 ° C x 50% RH,
After the treatment for 20 hours, the surface specific resistance of the surface of the non-coated film was measured under the above condition 1 and evaluated according to the following criteria. ◯: 1 × 10 ¹⁴ Ω / □ or more ×: less than 1 × 10 ¹⁴ Ω / □ The surface resistivity of the non-coated film used in the experiment was 1 × 10 ¹⁴ Ω / □ or more.

(3) Turbidity of coating layer In accordance with JIS-K6714, the turbidity of the film was measured by a sphere turbidimeter NDH-20D manufactured by Nippon Denshoku Industries Co., Ltd.
The difference between the turbidity of the coated film and the non-coated film and the turbidity of the coated film was measured and evaluated according to the following criteria. ◯: Film turbidity difference of less than 0.5% Δ: Film turbidity of 0.5% or more and less than 1% X: Film turbidity of 1% or more

The details of the coating layer components used in the following examples are as follows. [Coating layer component] (A) Antistatic component Antistatic agent (A1): The following formula synthesized from p-chloromethylstyrene and dimethylaminoethanol:

[0040]

[Chemical 4]

Monomer represented by (p-vinylbenzyldimethyl (2-hydroxyethyl) ammonium chloride, 45% by weight), methoxypolyethylene glycol monomethacrylate (NK ester M manufactured by Shin Nakamura Chemical Co., Ltd.)
-90G, 45% by weight), dimethylaminoethylmethacrylate (10% by weight) were dissolved in distilled water and heated as a polymerization initiator in a flask to about 60 ° C.
An aqueous solution of an antistatic resin obtained by polymerization by adding 2′-azobis (2-aminodipropane) dihydrochloride.

Antistatic agent (A2): Antistatic agent (A1)
An aqueous solution of an antistatic resin in which dimethylaminoethyl methacrylate of is acetoacetoxyethyl methacrylate. Antistatic agent (A3): Sodium dodecylbenzenesulfonate Antistatic agent (A4): Sodium polystyrene sulfonate (Versa TL-70 manufactured by NSC Japan) Antistatic property (A5): Formula:

[0043]

[Chemical 5]

Monomers represented by (methacryloylcholine chloride, 45% by weight), methoxypolyethylene glycol monomethacrylate (NK ester M-90G, 45% by weight, manufactured by Shin Nakamura Chemical Co., Ltd.), and dimethylaminoethyl methacrylate (10% by weight) were added. An antistatic resin obtained by polymerization by adding 2,2′-azobis (2-aminodipropane) dihydrochloride as a polymerization initiator while being dissolved in distilled water and being heated and expanded in a flask at about 60 ° C.

(B) Binder Component Binder Resin (B1): Aqueous Acrylic Resin (Nicarbide Industrial Co., Nicazole) (C) Thermosetting Component Crosslinking Agent (C1): Epoxy Crosslinking Agent (Nagase Chemtex, Denacol) ) Crosslinking agent (C2): Melamine crosslinking agent (manufactured by Dainippon Ink and Chemicals,
Beckamine) (D) Other ingredients Surfactant (D1): Nonylphenol-based surfactant (Liponox manufactured by Lion) Lubricant (D2): Colloidal silica (Snowtex manufactured by Nissan Chemical Co., Ltd.)

Example 1 Intrinsic viscosity 0.65 (35% in orthochlorophenol)
℃) polyethylene terephthalate (average particle size of about 2.4
1 μm pellet containing 0.005% μm silica particles)
After dried under hot air dried crystals at 80 ° C., it is fed to an extruder to obtain 280 to 280
The sheet was melt extruded from a T-die at a temperature of 300 ° C., cast on a mirror surface cooling drum whose temperature was adjusted to 20 ° C., and rapidly cooled to obtain an unstretched film having a thickness of about 720 μm.
Next, this film was stretched 3.7 times in the longitudinal direction at 85 ° C. to obtain a uniaxially stretched film. A coating solution prepared by diluting a polymer antistatic agent: A1 (99 parts by weight) and a surfactant: C3 (1 part by weight) with ion exchange water to a solid content concentration of 5% by weight as an antistatic layer on this film. On one side of the polyester film using a bar coater (about 6 μm (we
(t thickness). Next, it was stretched in the zone of 110 to 150 ° C. in the transverse direction by 3.9 times and heat-treated at 230 ° C. to obtain a 50 μm-thick biaxially stretched polyester film with crystal orientation completed. The coating film was dried by a heat treatment after the transverse stretching treatment to obtain a film provided with an antistatic layer. The haze of the polyester film obtained by this method is 1
%, And the total light transmittance was 89%. The characteristics of this film are shown in Table 2 below.

Examples 2 to 4 Biaxially stretched polyester films were obtained in exactly the same manner as in Example 1 except that the coating solution used in Example 1 was changed as shown in Table 1 below. The characteristics of this film are shown in Table 2.

Comparative Examples 1 to 3 Biaxially stretched polyester films were obtained in exactly the same manner as in Example 1 except that the coating liquid used in Example 1 was changed as shown in Table 1. The characteristics of this film are shown in Table 2.

Comparative Example 4 Table 2 shows the characteristics of the biaxially stretched polyester film obtained in Example 1 without applying the composition.

[0050]

[Table 1]

[0051]

[Table 2]

[0052]

According to the present invention, compared with the conventional one,
It is possible to provide an antistatic film having excellent antistatic properties, rear surface transfer properties, and transparency, and its industrial value is high.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C09K 3/16 104 C09K 3/16 104C // C08L 67:00 C08L 67:00 F term (reference) 4F006 AA35 AB16 BA07 CA01 CA07 DA04 4F100 AK01A AK11B AK41A AS00B BA02 CA22B CC01B EH46 EJ37 EJ86 GB15 GB90 JB13B JB16A JG03B YY00B 4J038 CC092 KA141 JA12 JA22 JA24 JA02 J24J0214J0214J012JA02B02J012DH02 DJ002 DJ0021 PA19 PC08 4J100 AB07P BA32P BA33P

Claims (5)

[Claims] 1. A coating solution containing a polymer antistatic agent (A) containing a repeating unit having a structure represented by the following general formula (I) as an essential component is applied to at least one surface of a thermoplastic resin film, and dried, An antistatic film having a stretched antistatic coating film. [Chemical 1] (In the above formula, R ¹ is H or a methyl group, and R ² has 1 carbon atom.
~ 5 aliphatic hydrocarbon group, R ³ and R ⁴ are each an aliphatic hydrocarbon group having 1 to 4 carbon atoms, and R ⁵ is 1 to 1 carbon atoms.
2 is an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a composite group thereof, X is a reactive group serving as a crosslinking point, and Y ⁻ is an anionic compound) 2. The antistatic film according to claim 1, wherein the thermoplastic resin film is a polyester film. 3. The antistatic film according to claim 1, wherein the antistatic agent (A) is a polymer containing 10 to 100% by weight of the repeating unit having the structure represented by the general formula (I). 4. A coating liquid comprising 5 to 100% by weight of an antistatic agent (A) and 0 to 9 of at least one binder resin (B).
The antistatic film according to claim 1, which is an aqueous coating liquid containing a solid content composition of 5% by weight. 5. A coating liquid comprising 5 to 100% by weight of an antistatic agent (A) and 0 to 9 of at least one thermosetting compound (C).
The antistatic film according to claim 1, which is an aqueous coating liquid containing a solid content composition of 5% by weight.