KR19980018027A - Biaxially Oriented Polyester Laminated Film - Google Patents

Abstract

The present invention relates to a polyester film which is widely used in medical, food, industrial, magnetic tape, and the like because of excellent physical properties such as crystallinity, elongation, chemical resistance, heat resistance, transparency, and the like, and in particular, surface roughness and It is devised to provide a biaxially oriented polyester film for lamination in which surface properties such as surface resistance and transparency are improved.

The present invention specifically relates to a laminated film obtained by laminating and biaxially stretching an antistatic polyester film and a general purpose polyester film, wherein at least 70% of the components of the antistatic polyester film are made of polyethylene terephthalate, and A biaxially oriented polyester laminated film using an anionic antistatic agent having a structure and a polyester film containing a certain amount of a silicone compound, polyethylene glycol and an antioxidant, and the polyester film thus prepared is antistatic as compared to a conventional laminated film. Physical properties such as transparency and transparency are improved.

Description

Biaxially Oriented Polyester Laminated Film

The present invention relates to a biaxially oriented polyester laminated film, and more particularly, to a biaxially oriented polyester laminated film in which physical properties such as surface resistance and surface roughness of a film are improved by adding a sulfonic acid metal salt anionic antistatic agent.

In general, polyester has a high degree of crystallinity and high softening point, high elongation, chemical resistance, heat resistance, transparency, etc. are widely applied to medical, food, industrial, photographic film, packaging, magnetic tape and the like.

However, polyesters have the drawback of causing various electrostatic problems because of their high electrical insulation. For example, in film forming, printing, and packaging processes, deterioration of workability and uneven printing due to foreign matter adhered to the surface of the film, generation of static electricity, electrostatic shock, etc., may cause deterioration of product quality.

Therefore, in order to solve such a problem, conventionally, an antistatic agent is applied to the surface or added to the inside of the film to improve the charging characteristics. In the case of applying to the surface of the film, the cost increase due to the coating process, antistatic There are drawbacks such as the effect of changes over time.

Conventional internal addition techniques for improving the antistatic properties of a film include a polyalkylene glycol or a method for producing a biaxially stretched film by simultaneously containing a polyalkylene glycol and a sulfonic acid metal salt, but polyalkylene is proposed. In the case of blending and using glycol in polyester, in order to sufficiently exhibit antistatic properties, 15.0 to 20.0 wt% polyalkylene glycol is required, and the chargeable polyester composition prepared here lacks physical properties such as oxidation stability, Mechanical properties such as elongation are lowered and color tone is increased, and antistatic film prepared by copolymerizing alkyl sulfonate metal salt and polyalkylene glycol to polyester has poor dispersibility of sulfonate metal salt, thus causing problems such as scratches on the surface of the film. It can also occur. In addition, when sulfonic acid metal salts and higher fatty acid metal salts are used to improve dispersibility, dispersibility is improved while antistatic property tends to be decreased.

The present invention has been made to solve the above problems, using an antistatic polyester film prepared by adding a specific sulfonic acid metal salt derivative, a specific silicon-based compound and an antioxidant for lamination with a general-purpose polyester film In particular, the object of the present invention is to provide an antistatic polyester laminated film having excellent transparency and surface properties.

The present invention is a biaxially stretched polyester laminated film obtained by the antistatic polyester film laminated and biaxially laminated a general-purpose polyester film, wherein at least 70% by weight of the components of the antistatic polyester film is made of polyethylene terephthalate 0.1-10.0% by weight of the anionic antistatic agent represented by the following formula (1) and the silicone-based compound represented by the formula (2) are 0.001 to 0.05 times by weight, and 0.03 to 10.0 weight of the polyethylene glycol component having an average molecular weight of 1,000 to 30,000, It is characterized by using a polyester film containing% and 0.01 to 5.0% by weight of antioxidant.

[Formula 1]

(In formula, n is 8-25 alkyl groups, M represents alkali metal or alkaline earth metals, such as Li, Na, K, Mg, Ca.)

[Formula 2]

Wherein R is -H, -CH ₃ , -CH ₂ CH ₃ , -CH ₂ CH ₂ CH ₃ , Χ is an integer from 0 to 100, and y is an integer from 1 to 100.)

C _n H _{2n + 1} in the mixture of Formula 1 is an alkyl group having an integer of 8 to 25, and when n is 7 or less or n is 26 or more, the dispersibility of sulfonic acid metal salts is lowered, and thus the antistatic property of the film and Transparency is greatly reduced. Such sulfonic acid metal salt is added to 0.05 to 10% by weight (preferably 0.2 to 8.0% by weight), but when the amount of the sulfonic acid metal salt is less than 0.05% by weight, it is difficult to exhibit sufficient antistatic properties, and it is more than 10% by weight. The antistatic property is excellent but the mechanical properties are lowered.

In addition, the silicone oil of the formula (2) used in the present invention may be used dimethyl polysiloxane, methyl ethyl polysiloxane, methyl propyl polysiloxane, methyl phenyl polysiloxane, hydrogen polysiloxane, etc., by selecting one of the silicone oil It is preferable to add 0.001-0.05 times by weight (more preferably 0.002-0.03 times by weight) relative to the amount of formula (1) used. If the amount of silicone oil added is less than 0.001% by weight, dispersibility of the metal sulfonate salt is lowered to generate coarse protrusions on the surface of the film. This worsens and causes coarseness.

In addition, the polyethylene glycol used in the present invention has a lower film dimensional stability and softening point when the average molecular weight is less than 1,000, and when the average molecular weight exceeds 30,000, the film transparency decreases, whitening occurs, but the antistatic property is increased. In addition, if the added amount is less than 0.03% by weight, the dimensional stability decreases, the transparency decreases, but sufficient antistatic property is not exhibited. If the added amount is more than 10.0% by weight, the adhesion and the antistatic property are excellent, but the color tone is increased, the transparency is decreased, and the mechanical properties Decreases.

Meanwhile, phosphorus compounds and phenolic compounds may be used as the materials mainly applied to polyester in the addition of antioxidants, and 0.01 to 5.0% by weight (more preferably 0.015 to 3.0) by selecting at least one of the two compounds. Weight percent). When the antioxidant is added in an amount less than 0.01% by weight, problems such as color tone increase and heat resistance decrease occur, and when added in excess of 5.0% by weight, problems such as transparency decrease and coarse particle increase occur.

The sulfonic acid metal salt derivative used in the present invention may be melt-extruded by making a high concentration of polyester master batch chip (MASTER BATCH CHIP) and blending it to a predetermined concentration in ordinary polyester.

On the other hand, the surface tension of the laminated film exhibits excellent ink and coating liquid adhesion at 30.0 to 65.0 dyne / cm (more preferably, 32.0 to 60.0 dyne / cm). It is not improved, and when it exceeds 65 dyne / cm, the heat resistance of a film falls.

Although the manufacturing method of the biaxially-stretched polyester laminated | multilayer film of this invention is not specifically limited, The method of making biaxially-oriented by biaxially stretching after making an unstretched laminated sheet melt-extruded by the T-Die method etc. is mainly used.

Such a polyester laminated film is produced in the thickness of about 5.0-200 micrometers.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, and the present invention is not limited thereto. Various performance evaluation of the film manufactured here was performed by the following method.

(1) extreme viscosity

The intrinsic viscosity of polyethylene terephthalate was measured at 25 ° C. using o-chlorophenol.

(2) transparency

The haze meter was measured according to ASTM-D1003, and the thickness of the sample was 100 µm laminated film. The lower the haze value, the better the transparency.

(3) adhesive

It evaluated based on ASTM-D335. The higher the surface tension, the better the adhesion between the ink and the coating liquid.

(4) surface resistance

Using a model R-503 of Gaosaki, a sample of a laminated film of 100 μm was prepared at 25 ° C. and 50% RH, and evaluated according to ASTM-D257.

(5) surface roughness

Maximum surface roughness was measured with the surface roughness meter based on JIS-B0601. If the maximum surface roughness is 0.1㎛ or less, it is determined that the surface characteristics are excellent.

Example 1

To the dimethyl terephthalate, 0.05% by weight of magnesium acetate, 0.04% by weight of antimony trioxide, 0.005% by weight of methylphenylpolysiloxane oil, and 0.03% by weight of phosphorous acid were added, and transesterification and condensation polymerization was performed with 70% by weight of ethylene glycol. Then, 1.0% by weight of polyethylene glycol having a molecular weight of 10,000 and 0.5% by weight of sulfonic acid metal salt were added thereto, followed by polymerization to produce polyethylene terephthalate (A) having an ultimate viscosity of 0.65. On the other hand, the polyethylene terephthalate (B) of usual intrinsic viscosity 0.65 was obtained by a well-known method. Here, two polyesters (A) and (B) were fed to the extruder 1 and the extruder 2, respectively, and melt-extruded to form an unstretched sheet having a three-layer structure as a laminate. After stretching by echo 4.0 times, heat setting was performed at 230 ° C. for 12 seconds to obtain a biaxially oriented laminated film having a thickness of 100 μm [(A) / (B) / (A) of 10 μm / 80 μm / 10 μm], and the performance evaluation results Are listed in Table 1.

[Examples 2 to 5 and Comparative Examples 1 to 5]

As shown in Table 1 below, the molecular weight and amount of polyethylene glycol, the amount of sulfonic acid metal salt and silicone compound added in the components of polyethylene terephthalate (A) were changed, and the type and amount of antioxidant were changed or mixed and other conditions were used in the examples. It carried out similarly to the 1, the performance evaluation is described in Table 1.

Table 1-a

division Composition of Polyethylene Terephthalate Sulfonic acid metal salts Silicone oil Polyethylene glycol Antioxidant Additive (wt%) Additive (wt%) .┐ / .┌ Molecular Weight Addition amount (% by weight) Kinds Addition amount (% by weight) Example 1 2 3 4 5 0.5110.17 0.0050.0050.010.050.07 0.010.0050.010.0050.01 10,0004,0004,00010,00020,000 1.00.54.00.10.5 Phosphorus phosphorus + phenol phosphorus phosphorus phosphorus 0.030.20.050.20.1 Comparative example 1 2 3 4 5 011115 0.010.0050.10.010.15 -0.0050.10.010.01 10,0004,00010,0001,00020,000 0.0115.00.51.00.1 Phosphorus phosphorus phosphorus phosphorus phosphorus phosphorus + phenol compound 0.150.20.057.00.1

TABLE 1-b

Film characteristics Surface resistance (Ω) Surface tension (dyne / cm) Haze (%) Surface roughness (㎛) 8.7 × 10 ¹⁰ 6.3 × 10 ¹⁰ 3.5 × 10 ¹⁰ 1.7 × 10 ¹¹ 5.2 × 10 ⁹ 52.352.853.651.554.1 1.31.21.51.01.8 0.060.060.070.080.09 10 ¹⁶ or more 1.4 × 10 ¹⁰ 6.8 × 10 ¹⁰ 4.7 × 10 ¹⁰ 2.4 × 10 ⁹ 36.252.751.353.252.1 0.75.64.85.16.2 0.070.190.340.210.26

Note 1) Metal sulfonate: Sodium dodecylbenzenesulfonate.

Note 2) Silicone oil: methylphenyl polysiloxane.

Note 3) Antioxidant: Phosphorus-based compounds represent phosphorous acid.

Phenolic type is 1,3,5, -tris (4-t-butyl-3-hydroxy-2,6-dimethylbenzyl)

1,3,5-triazine-2,4,6- (1H, 3H, 5H) -trione.

As can be seen from the above examples and comparative examples, the laminated film prepared according to the present invention is excellent in antistatic properties, transparency, and the like, which is required for almost all fields such as graphic arts, packaging, and magnetic fields requiring transparency and antistatic properties at the same time. There is utility such as being applicable.

Claims (5)

In the biaxially stretched polyester laminated film obtained by laminating and biaxially stretching an antistatic polyester film and a general purpose polyester film, 70% or more of the components of the antistatic polyester film are made of polyethylene terephthalate, 0.05-10.0% by weight of anionic antistatic agent, and the silicone-based compound represented by Formula 2 are 0.001-0.05 times by weight relative to the amount of the compound of Formula 1, 0.03-10.0% by weight of polyethylene glycol having an average molecular weight of 1,000-30,000, and an antioxidant. A biaxially oriented polyester laminated film characterized by using a polyester film containing 0.01 to 5.0% by weight. (Wherein C _n H _{2n + 1} is an alkyl group of 8 to 25 n, and M represents an alkali metal or alkaline earth metal such as Li, Na, K, Mg, Ca, etc.) Wherein R is -H, -CH ₃ , -CH ₂ CH ₃ , -CH ₂ CH ₂ CH ₃ , Χ is an integer from 0 to 100, and y is an integer from 1 to 100.) The biaxially oriented polyester laminated film according to claim 1, wherein the antistatic polyester film has an intrinsic viscosity in the range of 0.4-0.1 dl / g. The biaxially oriented polyester laminated film according to claim 1, wherein the antioxidant is used alone or in combination with an antioxidant of a phosphorus compound and / or a phenol compound. The biaxially oriented polyester laminated film according to claim 1, wherein the biaxially stretched laminated film has a thickness in a range of 5.0 to 200 µm. The biaxially oriented polyester laminated film according to claim 1, wherein the biaxially stretched laminated film has a surface tension of 30.0-65.0 dyne / cm.