KR101581089B1 - Resin composition and antistatic film comprising the same - Google Patents

Abstract

The present invention relates to a resin composition and an antistatic film comprising the resin composition, wherein the resin composition comprises an aqueous dispersion acrylic resin; A polyvinyl alcohol resin having a degree of polymerization of 600 or less and a degree of saponification of 80% or less; And an antistatic agent.

Description

[0001] Resin composition and antistatic film containing the same [0002]

The present invention relates to a resin composition coated to prevent electrification and an antistatic film coated with the resin composition.

Generally, a polyester resin is prepared by polymerizing an unsaturated fatty acid and a polyhydric alcohol to synthesize a linear unsaturated polyester, and reacting the monomer with a monomer such as styrene. Such polyester resins are easy to mold because they do not generate low molecular weight products such as water or alcohol during production, and their physical properties can be controlled according to additives, and they are applied to various industrial fields by molding into films.

However, the polyester resin has a low electric conductivity and a small water absorption amount, so that a film formed of a polyester resin has a problem that static electricity easily occurs.

Accordingly, various techniques have been developed for minimizing the generation of static electricity by imparting an antistatic function to a film molded from a polyester resin. Examples thereof include a method of adding an organic / inorganic internal antistatic agent, a method of forming a conductive polymer layer on a surface (see Patent Document), and a method of coating an external antistatic agent on the surface.

Among the above methods, the method of coating the external antistatic agent has a problem that the coating property is deteriorated in an environment where the initial antistatic property of the film is excellent but the relative humidity is high. In addition, there is a problem that the hardness of the antistatic layer formed on the surface of the film is not high, resulting in poor durability.

Korea Patent Publication No. 2009-0101091

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and it is an object of the present invention to provide a resin composition having excellent antistatic property and coating property and high hardness upon curing.

Another object of the present invention is to provide an antistatic film comprising the resin composition.

To achieve the above object, the present invention provides a water-dispersible acrylic resin composition comprising: A polyvinyl alcohol resin having a degree of polymerization of 600 or less and a degree of saponification of 80% or less; And an antistatic agent.

The present invention also relates to a substrate layer; And an antistatic film provided on the base layer and including an antistatic layer made of the resin composition.

The base layer may be made of a polyester resin.

Since the resin composition of the present invention contains a polyvinyl alcohol resin having a polymerization degree of 600 or less and a degree of saponification of 80% or less, the resin composition has excellent coating properties and has a high hardness upon curing. The antistatic film of the present invention is excellent in antistatic property and durability because the resin composition is coated.

Hereinafter, the present invention will be described.

1. Resin composition

The resin composition of the present invention is coated on a substrate to improve the antistatic property of the substrate, and includes a water-dispersed acrylic resin, a polyvinyl alcohol resin and an antistatic agent.

The water-dispersed acrylic resin contained in the resin composition of the present invention serves as a binder. That is, the water-dispersed acrylic resin plays a role of enhancing the adhesion (adhesiveness) with the substrate. The water-dispersed acrylic resin is not particularly limited as long as the acrylic resin is dispersed in a hydrophilic solvent. The acrylic resin is not particularly limited as long as it is known in the art, and examples thereof include methacrylate, methyl methacrylate, ethyl methacrylate, Butyl methacrylate, ethyl hexyl methacrylate, phenyl methacrylate, benzyl methacrylate, tolyl methacrylate, o-silyl methacrylate, glycerol methacrylate, ethylene glycol acrylate, ethylene glycol methyl acrylate, alkyl It is preferable that the water-dispersible acrylic resin is obtained by copolymerizing at least two kinds selected from the group consisting of allyl methacrylate, succinic methacrylate, glycidyl methacrylate and butyl acrylate.

The average particle size of the acrylic resin is not particularly limited, but is preferably 100 nm or less (specifically, 50 to 100 nm). If the average particle size of the acrylic resin exceeds 100 nm, the transmittance of the antistatic film may be lowered and the haze may be increased.

The hydrophilic solvent used for dispersing the acrylic resin is not particularly limited as long as it is well known in the art, and examples thereof include water and alcohol.

The water-dispersed acrylic resin of the present invention preferably contains 30 to 50% by weight of acrylic resin as a solid based on 100% by weight of the water-dispersed acrylic resin, and 50 to 70% by weight of a hydrophilic solvent.

On the other hand, the content of the water-dispersed acrylic resin in the resin composition of the present invention is not particularly limited, but it is preferably 1 to 40% by weight based on 100% by weight of the resin composition in consideration of adhesion and curability of the resin composition Do.

The polyvinyl alcohol (PVA) resin contained in the resin composition of the present invention has a degree of polymerization of 600 or less (specifically 200 to 600, preferably 400 to 600) and a degree of saponification of 80% or less , Preferably 50 to 80%, and more preferably 70 to 80%), which serves to increase the coating and hardness of the resin composition. The saponification degree means the degree of hydrolysis of polyvinyl acetate used in the production of polyvinyl alcohol resin.

The polyvinyl alcohol resin has high hydrophilicity. Among them, the polyvinyl alcohol resin having a degree of polymerization of 600 or less and a degree of saponification of 80% or less lowers the surface tension of the resin composition, thereby enhancing the coatability of the resin composition coated on the substrate . Specifically, the hydroxyl group of the saponified polyvinyl alcohol is present at the end of the coated surface, and as the surface tension is lowered, the coating property is improved. Also, since the polyvinyl alcohol resin is well-crosslinked with the water-dispersible acrylic resin, the hardness of the cured composition is also increased.

As described above, the resin composition of the present invention includes a polyvinyl alcohol resin having a certain degree of degree of polymerization and degree of saponification, and can exhibit excellent coatability and high hardness without containing a wetting agent or a curing agent.

That is, in the conventional resin composition used for antistatic treatment, a wetting agent is used to improve the coating property and a hardening agent is used to increase the hardness. However, the present invention does not require the use of a wetting agent or a hardening agent due to the polyvinyl alcohol resin .

The content of the polyvinyl alcohol resin is not particularly limited, but it is preferable that the content of the polyvinyl alcohol resin is 0.5 to 5% by weight based on 100% by weight of the resin composition in consideration of the coating property, curability and hardness of the resin composition.

The antistatic agent contained in the resin composition of the present invention serves to enhance the antistatic property of the resin composition. Such an antistatic agent is not particularly limited as long as it is known in the art, but it is preferably an imidazole type amphoteric surfactant having a molecular weight of 1,500 or less. The imidazole-based amphoteric surfactant contributes to the stabilization of the composition over time and can prevent the coating property of the composition from deteriorating even in a high relative humidity environment. Examples of such imidazole-based amphoteric surfactants include imidazolinium betaine and alkyl benzene sulfonate in the form of an ionic form (specifically, a quaternary ammonium salt imidazole ring is a cationic group And a substance in which a carboxyl group, a sulfonic acid group or the like is present as an anionic group) is not particularly limited. The content of such an antistatic agent is not particularly limited, but it is preferably 0.1 to 5% by weight based on 100% by weight of the resin composition, considering antistatic properties of the resin composition.

In addition, the resin composition of the present invention may further include a hydrophilic solvent to enhance the dispersibility of the water-dispersed acrylic resin and the polyvinyl alcohol resin. Such a hydrophilic solvent is not particularly limited, but may include water (distilled water) or alcohol. Examples of the alcohol include, but are not limited to, alcohols such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, tert- Alcohols, 1-ethyl-1-propanol, 2-methyl-1-butanol, n-hexanol and cyclohexanol.

Such a hydrophilic solvent fills the remaining portion (balance) in which the content of the components is excluded from 100 wt% of the composition.

The composition of the present invention may further include water-dispersed silica to improve slipperiness and anti-blocking property. Such water-dispersed silica is a silica dispersed in a hydrophilic solvent or a polymer resin. The content (solid content) of silica contained in the water-dispersed silica is not particularly limited, but is preferably 20 to 50% by weight based on 100% by weight of the water-dispersed silica. Also, the average particle size of the silica is not particularly limited, but it is preferably 40 to 200 nm in view of the slipperiness, the light transmittance of the constitution and the antistatic film, and the like.

The content of the water-dispersed silica is not particularly limited, but it is preferable that the amount of the water-dispersed silica is 0.1 to 2% by weight based on 100% by weight of the resin composition in consideration of the slip property and the antistatic property of the resin composition.

2. Antistatic film

The present invention provides an antistatic film comprising a base layer and an antistatic layer, which will be described in detail as follows.

The substrate layer included in the antistatic film of the present invention serves as a base and is made of a polyester resin having excellent chemical resistance, heat resistance, durability and mechanical strength. The polyester resin is not particularly limited as long as it is known in the art, but polyethylene terephthalate or polyethylene-2,6-naphthalene dicarboxylate can be given.

The method for producing the base layer with such a polyester resin is not particularly limited, but a polyester resin layer may be formed into a sheet through a melt extrusion process at 280 캜 and then subjected to uniaxial or biaxial stretching of about 2 to 5 times And the like. The thickness of such a base layer is not particularly limited, but is preferably 5 to 500 μm. If the thickness of the base layer is less than 5 탆, the rigidity and mechanical strength may be lowered, and if it exceeds 500 탆, the transparency may be lowered and the economical efficiency may be lowered.

The antistatic layer included in the antistatic film of the present invention is provided on the base layer and is made of the resin composition described above. A method of producing such an antistatic layer is not particularly limited, and a method of coating (coating) the resin composition on a substrate layer and then curing at 100 to 250 ° C can be mentioned. Here, the method of coating the resin composition is not particularly limited, but a coating method using a roll such as a gravure roll, a reverse roll, or a reverse gravure; A coating method using a bar such as Meyer bar; And coating methods such as an air knife method.

On the other hand, the thickness of the antistatic layer coated on the substrate layer is not particularly limited, but it is preferably 10 nm to 1 占 퐉 in consideration of the antistatic property of the antistatic film, light transmittance, and the like.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the following Examples are intended to illustrate one embodiment of the present invention, but the scope of the present invention is not limited by the following Examples.

[Example 1]

1) Preparation of resin composition

(Average particle diameter: about 100 nm), a polymerization degree of 1.2% by weight, a polyvinyl alcohol resin (PVA) having a degree of saponification of 80%, and 2.0% by weight of imide A sol-like amphoteric surfactant (ELEC AC manufactured by KAO) was added, and the mixture was stirred at 300 rpm for 20 minutes or longer to prepare a resin composition.

2) Antistatic film production

A polyethylene terephthalate (PET) unstretched film was stretched at a temperature of 70 to 90 占 폚 in the longitudinal direction of about 3.5 times to prepare a base layer film. The resin composition prepared above was coated and cured on one side of the prepared substrate layer film, stretched in the transverse direction at about 100 to 140 DEG C in the transverse direction, and thermally fixed at 210 to 245 DEG C to prepare a biaxially stretched antistatic film.

[Example 2]

A resin composition and an antistatic film were prepared in the same manner as in Example 1, except that a polyvinyl alcohol resin having a degree of polymerization of 600 and a degree of saponification of 80% was used instead of the polyvinyl alcohol resin having a degree of polymerization of 400 and a degree of saponification of 80%.

[Example 3]

The same procedure as in Example 1 was carried out except that a polyvinyl alcohol resin having a degree of polymerization of 600 and a degree of saponification of 80% was used instead of the polyvinyl alcohol resin having a degree of polymerization of 400 and a degree of saponification of 80% The resin composition and the antistatic film were prepared.

[Comparative Example 1]

A resin composition and an antistatic film were prepared in the same manner as in Example 1, except that a polyvinyl alcohol resin having a degree of polymerization of 1700 and a degree of saponification of 98% was used instead of the polyvinyl alcohol resin having a degree of polymerization of 400 and a degree of saponification of 80%.

[Comparative Example 2]

A resin composition and an antistatic film were prepared in the same manner as in Example 1, except that a polyvinyl alcohol resin having a degree of polymerization of 1700 and a degree of saponification of 80% was used instead of the polyvinyl alcohol resin having a degree of polymerization of 400 and a degree of saponification of 80%.

[Comparative Example 3]

A resin composition and an antistatic film were prepared in the same manner as in Example 1, except that a polyvinyl alcohol resin having a degree of polymerization of 600 and a degree of saponification of 98% was used instead of the polyvinyl alcohol resin having a degree of polymerization of 400 and a degree of saponification of 80%.

[Comparative Example 4]

A resin composition and an antistatic film were prepared in the same manner as in Example 1, except that a polyvinyl alcohol resin having a degree of polymerization of 400 and a degree of saponification of 98% was used instead of the polyvinyl alcohol resin having a degree of polymerization of 400 and a degree of saponification of 80%.

[Comparative Example 5]

(3M Company FC4420) was used instead of a polyvinyl alcohol resin having a degree of polymerization of 400 and a degree of saponification of 80%, and a cationic surfactant (LION Company ARQUAD 16-29) was used in place of the imidazole type amphoteric surfactant , A resin composition and an antistatic film were prepared.

[Comparative Example 6]

(3M company FC4420) was used instead of a polyvinyl alcohol resin having a degree of polymerization of 400 and a degree of saponification of 80%, and an anionic surfactant (UNION CARBAIDE, Inc., GR-5M) was used in place of the imidazole type amphoteric surfactant , A resin composition and an antistatic film were prepared.

[Comparative Example 7]

A resin composition and an antistatic film were produced in the same manner as in Example 1, except that a fluorinated surfactant (3M Company FC4420) was used instead of a polyvinyl alcohol resin having a degree of polymerization of 400 and a degree of saponification of 80%.

[Comparative Example 8]

(BYK Corp., BYK-349) was used in place of a polyvinyl alcohol resin having a degree of polymerization of 400 and a degree of saponification of 80%, and a cationic surfactant (LION Corp. ARQUAD 16- 29) was used in place of the antistatic film of Example 1, to thereby prepare a resin composition and an antistatic film.

[Comparative Example 9]

Modified siloxane surfactant (BYK-349 manufactured by BYK Corp.) was used in place of a polyvinyl alcohol resin having a degree of polymerization of 400 and a degree of saponification of 80%, and an anionic surfactant (UNION CARBAIDE GR- 5M) was used in place of the antistatic film of Example 1, to prepare a resin composition and an antistatic film.

[Comparative Example 10]

A resin composition and an antistatic film were prepared in the same manner as in Example 1, except that a polyester-modified siloxane surfactant (BYK-349 manufactured by BYK Corp.) was used instead of the polyvinyl alcohol resin having a degree of polymerization of 400 and a degree of saponification of 80% .

Examples 1, 2 and 3 and Comparative Examples 1 to 10 are summarized in Table 1 below.

division Example
One Example
2 Example
3 Comparative Example
One Comparative Example
2 Comparative Example
3 Comparative Example
4 Comparative Example
5 Comparative Example
6 Comparative Example
7 Comparative Example
8 Comparative Example
9 Comparative Example
10 Water dispersion
acryl
Suzy
(Solid content: 40% by weight) 8 8 8 8 8 8 8 8 8 8 8 8 8 PVA A degree of polymerization of 1700, a degree of saponification of 98% - - - 0.9 - - - - - - - - - Degree of polymerization 1700, degree of saponification 80% - - - - 0.9 - - - - - - - - Polymerization degree of 600, degree of saponification of 98% - - - - - 1.1 - - - - - - - Polymerization degree of 600, degree of saponification of 80% - 1.2 1.2 - - - - - - - - - - Degree of polymerization of 400, degree of saponification of 98% - - - - - - 1.1 - - - - - - Degree of polymerization of 400, degree of saponification of 80% 1.2 - - - - - - - - - - - - Fluoric surfactant - - - - - - - 0.8 0.8 0.8 - - - Polyester-modified siloxane
Surfactants - - - - - - - - - - 0.9 0.9 0.9 Cationic system
Surfactants - - - - - - - 2 - - 2 - - Anionic surfactant - - - - - - - - 2 - - 2 - Imidazole
Both sexes
Surfactants 2 2 2 2 2 2 2 - - 2 - - 2 Water dispersion
Silica - - 0.2 - - - - - - - - - - Distilled water 88.8 88.8 88.6 89.1 89.1 88.9 88.9 89.2 89.2 89.2 89.1 89.1 89.1 Total (% by weight) 100 100 100 100 100 100 100 100 100 100 100 100 100 Acrylic resin: copolymerization of methyl methacrylate and butyl acrylate monomer in a weight ratio of 1: 0.5 to 1: 0.6

[Experimental Example]

The physical properties of the resin composition prepared in Examples 1, 2, 3 and Comparative Examples 1 to 10 and the antistatic film were evaluated by the following evaluation methods, and the results are shown in Table 2 below.

1. Light transmittance (%): standard measurement method The light transmittance of an antistatic film was measured using a haze meter (NDH5000, Nippon Shokuhin Co., Ltd.) according to JIS K 7361.

2. Haze: Standard measurement method The haze of the antistatic film was measured using a haze meter (NDH5000, manufactured by Nippon Shokuhin Co., Ltd.) according to JIS K 7361.

3. Coefficient of Friction: The static friction coefficient and the coefficient of dynamic friction of the antistatic film-coated surface were measured under a load of 200 g using DAVENPORT's coefficient of friction measuring apparatus according to the standard measurement method ASTM D 1894 (good when the coefficient of static friction was 0.4 or less / 0.5 or more).

4. Surface resistance: The surface resistance of the antistatic film was measured with a surface resistance measuring device (Hirest up MCP-HT450 manufactured by Mitsubishi Chemical Corporation) according to JIS K 6911 (the lower the surface resistance, the better the antistatic property was evaluated) .

5. Flocculation: Whether or not the resin composition was allowed to stand for 1 hour and 24 hours under constant temperature and humidity conditions (observed if the flocculation did not occur and evaluated as NG if it occurred).

6. Surface Hardness: The resin composition thus prepared was placed in a rectangular container at a height of 50 mu m and dried in an 80 DEG C heat-resistant dry oven for 1 hour to prepare a film (antistatic layer) of about 5 mu m in thickness. The pencil hardness of the prepared film was measured five times at a weight of 500 g according to the standard measuring method JIS K 5600, and the pencil hardness at the time of not scratching more than twice was applied.

7. Surface Unevenness: The surface stain was evaluated by observing the appearance of the film by reflection and transmission under a three-wavelength lamp with a black plate under an antistatic film.

division Example
One Example
2 Example
3 Comparative Example
One Comparative Example
2 Comparative Example
3 Comparative Example
4 Comparative Example
5 Comparative Example
6 Comparative Example
7 Comparative Example
8 Comparative Example
9 Comparative Example
10 Transmittance
(%) 91.4 91.0 90.8 87.2 87.8 88.4 88.9 88.4 88.1 88.7 88.1 88.2 88.4 Haze (%) 1.58 1.67 1.7 2.9 2.5 2.1 2.4 2.8 2.9 2.7 3.1 3 2.9 Coefficient of friction tablet
(μs) 0.3 0.34 0.32 0.52 0.5 0.46 0.45 0.41 0.42 0.4 0.56 0.51 0.48 copper
(μk) 0.3 0.32 0.31 0.5 0.45 0.42 0.43 0.41 0.4 0.39 0.52 0.48 0.45 Surface resistance (Ω / sq) E + 10 E + 10 E + 10 E + 12 E + 11 E + 12 E + 11 E + 13 E + 12 E + 10 E + 13 E + 12 E + 10 Aggregation OK OK OK NG NG NG NG NG NG NG NG NG NG Surface stain OK OK OK NG NG NG NG NG NG NG NG NG NG Surface hardness H 2H 2H HB H B B 3B 3B 3B 2B 2B 2B

Referring to Table 2, it can be seen that the antistatic film coated with the composition of the present invention has excellent antistatic property due to low surface resistance and does not cause coagulation and surface unevenness, and thus has excellent coatability of the composition. Specifically, it can be confirmed that the coating composition of the present invention using the polyvinyl alcohol resin is more excellent in the coating property than the case of using the fluorine surfactant or the polyester modified siloxane surfactant to improve the coating property.

Claims (8)

Based on 100% by weight of the resin composition,
1 to 40% by weight of water-dispersed acrylic resin;
0.5 to 5% by weight of a polyvinyl alcohol resin having a polymerization degree of 600 or less and a degree of saponification of 80% or less;
0.1 to 5% by weight of an antistatic agent; And
And a hydrophilic solvent balance. The method according to claim 1,
The acrylic resin contained in the water-dispersed acrylic resin may be selected from the group consisting of methacrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, ethylhexyl methacrylate, phenyl methacrylate, benzyl methacrylate , Tolyl methacrylate, o-silyl methacrylate, glycerol methacrylate, ethylene glycol acrylate, ethylene glycol methyl acrylate, alkylaryl methacrylate, succinic methacrylate, glycidyl methacrylate, and butyl acrylate Wherein at least two kinds of resins selected from the group consisting of The method according to claim 1,
Wherein the antistatic agent is an imidazole-based amphoteric surfactant. The method according to claim 1,
And water-dispersed silica. delete delete A base layer; And
An antistatic film comprising an antistatic layer formed on the base layer and made of the resin composition of any one of claims 1 to 4. 8. The method of claim 7,
Wherein the substrate layer is made of a polyester resin.