KR19980020222A - Manufacturing method of polyester film excellent in antistatic property - Google Patents

Abstract

The present invention is a polyester composed of dicarboxylic acid and ethylene glycol as a main component of 0.1 to 20% by weight of the sulfonate component of the following general formula (I), 0.01 to 5% by weight of the silicone oil component of the following general formula (II) and A polyester copolymer is prepared by drying, applying and extruding 0.5 to 10% by weight of a polyethylene glycol component having a molecular weight of 1,000 to 20,000 by an esterification reaction. 50 to dimethyl terephthalic acid as an acid component on one side or both sides of an unstretched or uniaxially stretched film. 60% by weight, dimethyl isophthalic acid 20-50% by weight, dimethyl isophthalic acid metal salt 2-15%, coating a water-soluble copolymer of 20 to 99% by weight of ethylene glycol, 0.5 to 10% by weight of diethylene glycol as the diol component It relates to a method for producing a polyester film excellent in antistatic properties.

C _n H _{2n + 1} -Ar-SO ₃ M ·········· (Ⅰ)

In the formula (I), n is an integer of 1 to 20, M represents an alkali or alkaline earth metal, and Ar represents an aromatic or aliphatic residue.

Among the above-mentioned formula (Ⅱ), R ₁ is _{-H, -OH, -OCH 3, -NH} 2, -COOH, -COOCH 3, -CH 3, Or -CH-CH ₂ , and R ₂ is -CH ₃ , -H, -COOH, -NH ₂ or , X is an integer of 0 to 100, Y is an integer of 1 to 100.

Description

Manufacturing method of polyester film excellent in antistatic property

The present invention relates to a method for producing a polyester film excellent in antistatic properties, and more specifically, to a single or both sides of an unstretched or uniaxially stretched film by mixing, drying, melting and extruding a polyester and an antistatic copolyester. The present invention relates to a method for producing a polyester film having excellent antistatic property by coating a water-soluble copolymer and stretching in the width direction.

In general, polyester has high mechanical properties and optical properties such as high crystallinity, high softening point, high elongation, flexural strength, chemical resistance, heat resistance, transparency, and so on, and thus pharmaceutical, food, industrial parts, petroleum products, general film, deposition and photo film. It is widely applied to capacitors, capacitors and labels.

However, the polyester film is an insulating material and has a surface resistance value (measurement standard ASTM D-257) of 16 ohm or more, and attracts dust or foreign matter by charging it very easily through frequent contact and separation between films or other objects. Pulling is likely to cause adverse effects on the quality of the process or product.

In particular, the present invention relates to a method for producing a polyester film having excellent antistatic properties mainly used in industrial applications such as packaging, labels, microfilm, graphics (masking, layout base) where the generation of static electricity is a problem.

There are various treatment methods for imparting the function of preventing static electricity. First, a method of depositing a metal on a polyester film, adding conductive fine particles to disperse the inside of the polyester film during melt extrusion, or dispersing conductive fine particles And a method of applying a surfactant to the surface of the film, a method of applying a surfactant type antistatic agent to the inside of the film during the manufacturing process, or applying the film to the surface of the film. The method of using the double surfactant is the most economical and effective compared to the above methods, but the method of applying the ionic antistatic agent to the surface of the polyester film can be applied to the surface of the coated film as can be seen in the processing examples of other films. Sticking, the problem that the antistatic agent of the applied film surface is easily transferred to the surface of the other film or the object was a major disadvantage was poor stability over time.

In the past, various methods have been proposed to solve this problem. For example, in order to exhibit sufficient antistatic properties in a known method of blending polyols with polyesters, a large amount of 15 to 20% by weight of polyols is required and the antistatic polyester compositions thus prepared have physical properties, in particular oxidative stability. Insufficient mechanical properties such as elongation and color tone increase. On the other hand, the antistatic polyester copolymerized with polyalkylene sulfonate and polyethylene glycol to polyester has a relatively small decrease in physical properties. However, this method has a large amount of foaming during the polymerization process, resulting in process problems, reduced productivity, and fiber products. Deterioration of the sacrificial property due to the pack pressure increase during spinning, the decrease in the uniformity of physical properties and the deformability of the film due to the hunting of the filter pressure and load in the melting and extrusion processes during the manufacture of the film products frequently Is generated. In addition, the product made of the conventional antistatic polyester composition is difficult to commercialize the product due to the severe change of physical properties over time.

The present invention aims to solve the above problems and to produce a polyester film which can exhibit excellent physical properties and process stability, in particular excellent antistatic property. That is, an antistatic polyester film having excellent properties that solved the above problems by applying a specific alkyl sulfonic acid metal salt, polyethylene glycol having an average molecular weight of 1,000 to 20,000, and a copolymer containing a specific amount of a specific silicone-based polymer. Could be prepared.

As described above, the present invention provides a polyester composed of dicarboxylic acid and ethylene glycol as a main component, in which 0.1 to 20% by weight of a sulfonate-based component of the following general formula (I) and 0.01 to 5% by weight of a silicone oil component of the following general formula (II) % And 0.5 to 10% by weight of a polyethylene glycol component having a molecular weight of 1,000 to 20,000 is prepared by esterification, followed by drying, melting, and extruding to produce dimethyl terephthalic acid as an acid component on one side or both sides of an unstretched or uniaxially stretched film. 50 to 60% by weight, 20 to 50% by weight of dimethylisophthalic acid, 2 to 15% of dimethyl isophthalic acid metal salt, and a water-soluble copolymer of 20 to 99% by weight of ethylene glycol and 0.5 to 10% by weight of diethylene glycol as the diol component. It is characterized by producing a polyester film excellent in antistatic properties by coating.

C _n H _{2n + 1} -Ar-SO ₃ M ·········· (Ⅰ)

In the formula (I), n is an integer of 1 to 20, M represents an alkali or alkaline earth metal, and Ar represents an aromatic or aliphatic residue.

Among the above-mentioned formula (Ⅱ), R ₁ is _{-H, -OH, -OCH 3, -NH} 2, -COOH, -COOCH 3, -CH 3, Or -CH-CH ₂ , and R ₂ is -CH ₃ , -H, , -COOH, -NH ₂ or , X is an integer of 0 to 100, Y is an integer of 1 to 100.

In the present invention, the main material of the composition is dimethyl terephthalic acid and ethylene glycol as a main component of polyethylene glycol having a molecular weight of 1,000 to 20,000 0.5 to 10% by weight of the component, 0.1 to 20% by weight of the sulfonate component of the general formula (I), After the esterification of 0.01 to 5% by weight of the silicone oil component of Formula (II) in a conventional manner or before polycondensation, the reaction is carried out to prepare a polyester copolymer, which is then mixed with a particle-free saliva. Then, the non-stretched film obtained through the drying, melting, and extruding process was stretched 3 to 5 times in the longitudinal direction at the stretching temperature of 80 to 150 ° C., and the transparency was imparted to the antistatic property, characterized by the range of 9 to 188 μm. It is to manufacture this excellent polyester film.

In the above description, when polyethylene glycol has an average molecular weight of 1,000 or less, polyester antistatic property decreases and foaming is severe during esterification, and many troubles occur in the polymerization process, and when the average molecular weight is 20,000 or more, transparency and dimensional stability decrease. And whitening phenomenon occurs and the antistatic property is increased, but tendency is poor. When the amount of polyethylene glycol added is 0.5% by weight or less, troubles in the polymerization process decrease, and dimensional stability and transparency decrease, but sufficient antistatic property is not exhibited. If the added amount is 10% by weight or more, the adhesion and antistatic properties in the final product are excellent, but dimensional stability is lowered, transparency is lowered, and mechanical properties are lowered. Preferably, the average molecular weight of polyethylene glycol is 2,000 to 10,000, and the amount thereof is preferably 1.0% by weight to 8% by weight.

And, in the components represented by the general formula (I), M represents an alkali or alkaline earth metal, and as the type, sodium, magnesium, potassium, etc. may be applied, and Ar represents an aliphatic or aromatic carbon compound having 6 or more carbon atoms. When the number of carbon atoms is 5 or less, compatibility with polyester is lowered and durability of moldability and antistatic property is lowered. In general, Ar is preferably an alkyl group having 6 to 18 carbon atoms or an aromatic substance.

In the general formula (I), n represents a compound having an integer of 1 to 20. If n is an integer of 1 or less or 20 or more, problems similar to those in Ar are used. Thus, an integer of n to 2 to 15 is used. It is desirable to.

When the amount of the sulfonic acid metal salt-based component described in the general formula (I) is 0.1 wt% or less, it is excellent in transparency, mechanical properties, moldability, etc., but it is difficult to exert sufficient antistatic properties, and when it is 20 wt% or more, antistatic Although excellent in properties, transparency and color tone deteriorate, and mechanical properties deteriorate. Preferably, 1 wt% to 0.8 wt% is added.

The silicone oil of the general formula (II) includes dimethylpolysiloxane, methylhydroxypolysiloxane, hydropolysiloxane, methylphenylpolysiloxane, alkyl modified silicone, amino modified silicone, carboxy modified silicone, higher fatty acid modified silicone, and epoxy modified silicone. , Vinyl group-containing silicones, alcohol-modified silicones, polyether-modified silicones, alkyl polyether-modified silicones, and the like, may be used, and one of the silicone oils may be used to add 0.01 wt% to 5 wt%. When the amount of silicone oil added is less than 0.01% by weight, the transparency and cohesiveness are good, but it causes an increase in the distillation column of the distillation column during the polymerization process. Excellent, but poor transparency and cohesiveness. Preferably, one selected from polyether modified silicone, alkyl polyether modified silicone, higher fatty acid silicone, methylhydroxypolysiloxane and methylphenylsilicone may be used in an amount of 0.01% by weight to 3.0% by weight.

Meanwhile, phosphorus compounds and phenolic compounds may be used as the materials mainly applied to polyesters in the addition of antioxidants, and 0.01 to 5% by weight is selected by selecting any one of the two compounds. When the antioxidant is added in an amount of 0.01% by weight or less, problems such as heat resistance deterioration, color tone increase, coarse particle increase, and transparency decrease may occur. Preferably 0.01 to 3% by weight is added.

It will be described in more detail with reference to the following Examples, the physical properties measurement method in the Examples are as follows.

(1) haze (ASTM-D1003)

(2) Adhesive (ASTM-D3359)

(3) Surface specific resistance (Evaluation based on ASTM-D257 at Gao Saki Model R-503 Temperature 25 ℃, Humidity 50% RH)

(4) Tensile strength (evaluated according to ASTM-D882 standard using a film manufactured by Toyo Seiki Co., Ltd.)

(5) Surface tension (ASTM D-2578)

(6) peel strength

The thermal transfer machine is a product of Toyo Seiki Co., Ltd., using 5 cells of 1cm × 3cm, heat-bonding the standard sample and the sample at a pressure of 4㎏ / ㎠ for 15 seconds at 200 ° C. 5 cells were sequentially peeled off at an angle of 180 ° C. and then averaged.

Detailed examples are as follows.

Example 1

100% by weight of dimethyl terephthalic acid and 70% by weight of ethylene glycol were added with an ester exchange catalyst, followed by heating under normal pressure. After addition, a polycondensation reaction was carried out to prepare a polyester copolymer having an intrinsic viscosity of 0.65. The polyester copolymer prepared here and general polyester were mixed at a weight ratio of 1: 9, and these were dried under vacuum at 160 ° C. for 6 hours, and then melt-extruded at 290 ° C. at a discharge rate of 1500 kg / h to draw in the longitudinal direction. After stretching 3.5 times at 120 ° C. and stretching 4.0 times in the width direction, the film was heat-fixed at 220 ° C. for 12 seconds to prepare a film having a thickness of 12 μm. In this embodiment, in the structural formula of the sulfonic acid metal salt C _n H _{2n + 1} -Ar-SO ₃ M, n is 12, Ar is an aromatic residue, and M is sodium. It was.

Example 2

After the longitudinal stretching in Example 1, after the corona treatment, the water-soluble copolymer prepared above was coated on both sides using a reverse gravure coater so that the coating dry thickness was 0.01 to 0.05 μm. Other conditions were carried out in the same manner as in Example 1, the results of the evaluation of the characteristics are shown in the following table.

Example 3

After the longitudinal stretching in Example 1, after the corona treatment, the water-soluble copolymer prepared above was coated on both sides using a reverse gravure coater so that the coating dry thickness was 0.01 to 0.05 μm. Other conditions were carried out in the same manner as in Example 1, the results of the evaluation of the characteristics are shown in the following table.

Example 4

On the coating surface of the film prepared in Example 2, aluminum was deposited by boat method under vacuum in a conventional manner to obtain a light density of 2.5, and a vapor deposition film was obtained. The results of the evaluation of the characteristics are shown in the following table.

Example 5

On the coated surface of the film in Example 3, aluminum was deposited by a boat method under vacuum in a conventional manner so as to have a light density of 2.5, and a vapor deposition film was obtained. The results of the evaluation of the characteristics are shown in the following table.

Comparative Example 1

Ordinary polyester was used without using the polyester copolymer in Example 1. Other conditions were carried out in the same manner as in Example 1, the results of the evaluation of the characteristics are shown in the following table.

Comparative Example 2

After the longitudinal stretching in Comparative Example 1, after the corona treatment, the water-soluble copolymer prepared above was coated on both sides using a reverse gravure coater so that the coating dry thickness was 0.01 to 0.05 μm. Other conditions were carried out in the same manner as in Example 1, the results of the evaluation of the characteristics are shown in the following table.

Comparative Example 3

The vapor deposition film was obtained by vapor-depositing aluminum by the boat method by the conventional method so that the optical density may be set to 2.5 on the coating surface of the film which was manufactured in the comparative example 2, and the characteristic evaluation result is shown in the following table.

[table]

Claims (4)

0.1 to 20% by weight of sulfonic acid salt component of the following general formula (I), 0.01 to 5% by weight of silicon oil component of the following general formula (II) and molecular weight of 1,000 to a polyester composed of dicarboxylic acid and ethylene glycol as main components 0.5 to 10% by weight of a polyethylene glycol component of 20,000 to 20% by weight of the esterification reaction to prepare a polyester copolymer, dried, applied and extruded 50 to 60% by weight of dimethyl terephthalic acid as an acid component on one or both sides of the unstretched or uniaxially stretched film 20 to 50% by weight of dimethyl isophthalic acid, 2 to 15% of dimethyl isophthalic acid metal salt, and a water-soluble copolymer comprising 20 to 99% by weight of ethylene glycol and 0.5 to 10% by weight of diethylene glycol as the diol component. Method for producing a polyester film excellent in antistatic properties. C _n H _{2n + 1} -Ar-SO ₃ M ·········· (Ⅰ) In the formula (I), n is an integer from 1 to 20, M represents an alkali or alkaline earth metal, Ar represents an aromatic or aliphatic residue. In the formula (II), R ₁ is _{-H, -OH, -OCH 3, -NH} 2, -COOH, -COOCH 3, -CH 3, Or -CH-CH ₂ , R ₂ is -CH ₃ , -H, -COOH, -NH ₂ or Indicates X is an integer from 0 to 100, Y is an integer from 1 to 100. The method for producing a polyester film having excellent antistatic property according to claim 1, wherein the film is stretched 3 to 5 times in the longitudinal direction at a stretching temperature of 80 to 150 ° C so as to have a thickness of 9 to 188 µm. The silicone oil component according to claim 1, wherein the silicone oil component is dimethyl polysiloxane, methyl hydroxy polysiloxane, hydrogen polysiloxane, methylphenyl polysiloxane, alkyl modified silicone, amino modified silicone, carboxy modified silicone, higher fatty acid modified silicone, epoxy modified silicone, And vinyl group-containing silicone, alcohol-modified silicone, polyether-modified silicone, or alkyl polyether-modified silicone. The method for producing a polyester film having excellent antistatic property according to claim 1, wherein 0.01 to 5% by weight of a phosphorus compound and a phenol compound are added as an antioxidant.