KR100470445B1 - Direct extrusion coatable polyester film coated water soluble composition - Google Patents

Abstract

The present invention is an ethyleneimine produced by reacting a primary amine compound in which 20 to 25% is substituted with an acetyl group (-NHCOCH ₃ ) as a main component of a polymer composition on one or both sides of an extruded polyester film and a ketone or an aldehyde. 0.01 to 5.00% by weight of the modified polyethyleneimine resin obtained by cationic polymerization as a solid content, 0.01 to 1.00% by weight of silicon dichloride having a curing agent, a coupling agent, and a particle size of 0.5 μm as additives, respectively, A water-soluble coating liquid made of a polar solvent such as water is applied before the longitudinal stretching to evaporate the polar solvent by the temperature in the infrared heater and the stretching machine, or after the longitudinal stretching, the water-soluble coating liquid is applied to heat the transverse stretching machine. By evaporating the solvent, the adhesion between the polyester film and the coated polymer layer is excellent. Eopeumyeonseo King, even when exposed to a humid environment for a long time have excellent moisture resistance for maintaining the adhesive strength of the first, provides the in-line coated polyester film to lower the environmental problems or fire hazards due to organic solvents.

Description

Direct extrusion coatable polyester film coated water soluble composition

The present invention is to produce a direct extrusion coated polyester film coated with a water-soluble composition.

Generally, oriented polymer films, especially biaxially oriented polyethylene terephthalate films, have excellent mechanical properties and are widely used in fields such as packaging materials, magnetic tapes, and graphic films. However, they have difficulty in processing due to poor adhesion to other polymer materials. .

In particular, in order to give heat sealing properties that the polyester film does not have, low-density polyethylene should be extruded and laminated.

However, when the polyester film is used in the lamination field, since the surface of the film is composed of an inert group, the primer must be treated to give adhesion to other polymer materials.

Due to this problem, post-processing companies for polyester film have to corona discharge or anchor coating the film surface, then process it into packaging materials, magnetic tape, graphic film, or extrusion coating other polymer materials. For this reason, expensive equipment such as a corona treatment device or an anchor coater is required, and production constraints are generated due to environmental regulations on anchor coating liquids.

Therefore, as a part of the film extrusion process, coating is performed with a polymer liquid which can improve the adhesive force of the film before or after the longitudinal stretching process or between longitudinal stretching and transverse stretching so that a post processing company does not need an additional process such as corona treatment or anchor coating. As a result, research to provide a surface-treated film has been actively conducted under the name of direct extrusion coating film.

Including the coating process as part of the film extrusion process as described above is called in-line coating.

In US Pat. No. 4,410,600 as an example of a direct extrusion coated polyester film, a copolymer of styrene and maleic-anhydride was inline coated onto a biaxially oriented polyester film to impart adhesion to low density polyethylene.

However, the film coated in this manner lacks adhesion to low-density polyethylene and requires a separate corona treatment before post-processing, and loses adhesion to the extruded coated resin layer when the coated film is exposed to moisture. There is this.

In addition, in US Pat. No. 4,571,363, the thermosetting acrylic polymer was inline-coated to give adhesion to the ionomer, but there was a problem that the adhesion was insufficient compared to the anchor coating in post-processing.

In US Pat. No. 5,156,904, polyethyleneimine alone was used as an inline coating on a polyethylene terephthalate film to give adhesion to a low density polyethylene resin. There is a problem that the film breaks, the adhesive strength with the ionomer is significantly insufficient, there is a problem that the adhesive strength is easily lost by the moisture contained in the air.

Therefore, an object of the present invention is to solve the above problems, and excellent adhesion between the polyester film and the coated polymer layer, even without exposure between the film and the film, even if exposed for 3 months at 80% relative humidity It is to provide a method for solving the environmental problems and fire risks due to organic solvents, having excellent moisture resistance to maintain the initial adhesion.

The present invention for achieving the above object is a primary amine compound in which 20 to 25% is substituted with acetyl group (-NHCOCH ₃ ) as the main component of the polymer composition on one or both sides of the extruded polyester film, and ketone Or 0.01 to 5.00% by weight of a modified polyethyleneimine resin obtained by cationic polymerization of ethyleneimine produced by reacting with an aldehyde as a solid content, and a hardener, a coupling agent, and a silicon dichloride having a particle size of 0.5 μm as 0.01 additives, respectively. A water-soluble coating liquid containing from 1 to 1.00% by weight, the remainder being a polar solvent such as water, is applied before longitudinal stretching to evaporate the polar solvent by the temperature in the infrared heater and the stretching machine, or after the longitudinal stretching, the aqueous coating. Polyester film for direct extrusion coating, by applying a liquid to evaporate the solvent by the heat of the transverse stretching machine. It provides a process for producing the same.

The water-soluble modified polyethyleneimine-based resin used in the present invention is an ethyleneimine produced by reacting a primary amine compound in which 20 to 25% of the total primary amine content is replaced with an acetyl group (-NHCOCH ₃ ), and a ketone or an aldehyde. Was used by cationic polymerization.

The primary amine group of the modified polyethyleneimine resin thus formed reacts with a hydroxyl group or a carboxyl group on the surface of the polyester film to form a chemical bond between the modified polyethyleneimine coating film and the polyester film.

The chemical bonds thus generated are increased in activity of the functional groups during the stretching process, so that the adhesive force may be improved as compared with the film produced by the offline coating, which is a method according to the prior art.

In addition, since the main component of the modified polyethyleneimine coating film applied to the polyester film surface and dried is polyethylene, when lamination is performed with a polyolefin in a molten state, excellent adhesion can be exerted by heat and pressure.

At this time, the primary amine compound is used to replace 20 to 25% of the total content of the primary amine with an acetyl group (-NHCOCH ₃ ).

The content of water-soluble modified polyethyleneimine-based resin is 0.01 to 5.00% by weight is appropriate, but less than 0.01% by weight of the coating amount is insufficient, there is a problem of insufficient adhesive strength, when it exceeds 5.00% by weight blocking properties between films The problem arises that it becomes impossible to wind up.

The water-soluble modified polyethyleneimine-based resin is prepared into a water-soluble composition liquid by dissolving it in a polar solvent such as water together with additives. As a participant used, a coupling agent, a curing agent, and silicon dichloride having an average particle size of 0.5 μm is used.

As the coupling agent, titanate coupling agents such as titanium acetyl acetone, titanium ethyl acetoacetate, and triethanolamine titanate may be used, and by using together with a curing agent, it is possible to improve blocking resistance, moisture resistance, and adhesion.

Blocking between films is caused by functional groups remaining in the coating film that do not participate in the reaction, migrate to the surface of the coating film and stick to the back side of the coated polyester film.

In addition, the decrease in moisture resistance and adhesion of the film is caused by using a water-soluble composition liquid in which the resin is water-soluble or emulsified. In the water-soluble composition liquid, a considerable amount of hydrophilic groups remain in the coating coating film even after drying, When it reacts with water in the water, it serves to hydrolyze the coating film, which eventually causes the moisture resistance and the adhesive strength of the film to be lowered.

In order to solve such a problem, it adds, a coupling agent and a hardening | curing agent.

At this time, the amount of the coupling agent and the curing agent is preferably 0.01 to 1.00% by weight, when the amount exceeds 1.00% by weight there is a problem that the coating film hardness is too hard.

However, the coupling agent and the curing agent must be used together, and when these are used alone, there is a problem that the moisture resistance is not improved.

The curing agent may be epoxy-based curing agent such as aliphatic epoxide, melamine-based curing agent such as melamine acrylic, melamine formaldehyde, isocyanate-based curing agent such as toluene diisocyanate and aziridine-based curing agent such as alkyl ester, and may be coated with a coating agent. By controlling the degree of curing, the blocking resistance, adhesive force and moisture resistance can be improved.

On the other hand, silicon dichloride plays a role of improving the blocking resistance and slip resistance by increasing the roughness of the coating coating film, when the average particle size is 0.5㎛ and the error range of 0.01㎛ has the weakest roughness between the films. .

The amount of silicon dioxide used is preferably 0.01 to 1.00% by weight. If the amount of silicon dioxide is less than 0.01% by weight, there is a problem of insufficient slip improvement and blocking prevention effect, and when it exceeds 1.00% by weight, a problem occurs in the haze of the film. do.

As a method of applying the composition solution to the polyester film, a conventional coating method such as a coating method using a roll such as a gravure roll or a reverse gravure roll, a coating method using a mayor bar, or a coating method using an air knife may be used.

Since the polyester film coated with the water-soluble composition is thermally cured and dried in the stretching machine maintained at a temperature of 210 to 240 ° C., a film having improved adhesion can be obtained.

Since the surface of the polyester film obtained in this way is polyethylene as a main component of a coating film, when lamination is carried out with polyolefin in a molten state, excellent adhesive force can be exhibited by heat and pressure.

Polyolefin resins used herein include low density polyethylene, ethylene-vinylacetate copolymer, polyvinyl alcohol, polyvinylacetate, and the like, in particular, in order to impart adhesion to non-polymeric materials such as heat sealability or aluminum foil. Many low-density polyethylenes are used.

In addition, when extruded and coated with a polymer that lacks adhesion with a polyester film, such as ionomer, it exhibits excellent adhesion. In particular, it provides excellent adhesion to the DuPont (Surlyn) series.

Hereinafter, the present invention will be described in more detail with reference to the following Examples, but is not limited to the following Examples of the present invention.

First, a biaxially stretched polyester film coated with a water-soluble composition was prepared by the following method.

Example 1

3.0 wt% of BASF's Polymin as a water-soluble modified polyethyleneimine resin, and 0.5 wt% of Titanium chelete (TC-42) from From CS as a coupling agent After mixing 0.5% by weight of silicon dioxide with HY800 as an additive, HY800, an epoxy-based curing agent, was mixed with 0.1% by weight of the mixed solution, and a water-soluble composition was prepared in which the rest was filled with water.

The water-soluble composition prepared above was coated on one side of the polyester film stretched 3.5 times at 80 ° C. in the longitudinal direction using a Meyer bar coating method so that the thickness of the solid layer was 3.0 μm and the thickness deviation was less than 0.03 μm. The film was dried while stretching three times at 230 ° C. in the transverse direction to prepare a polyester film coated with a water-soluble composition, and then experimented by the method described below, and the results are shown in Table 1.

<Example 2>

Using the same apparatus and method as in Example 1, but using an isocyanate-based curing agent Oran Veranechin-U as an additive to prepare a polyester film coated with a water-soluble composition solution by the method described below The experiment was performed and the results are shown in Table 1 together with Example 1.

<Example 3>

Using the same apparatus and method as in Example 1, but using a acid-cure of Goodrich (melamine-based curing agent) as an additive to prepare a polyester film coated with a water-soluble composition solution, and then experimented by the method described below And the results are shown in Table 1 together with Example 1.

<Example 4>

Using the same apparatus and method as in Example 1, using the CX-100 of Zenica, an aziridine-based curing agent as an additive to prepare a polyester film coated with a water-soluble composition, and then experimented by the method described below And the results are shown in Table 1 together with Example 1.

Comparative Example 1

Using the same apparatus and method as in Example 1, but preparing a polyester film without coating the water-soluble composition, the experiment was carried out by the method described below and the results are shown in Table 1 together with Example 1.

Comparative Example 2

Using the same apparatus and method as in Example 1, except that a polyester film coated with a water-soluble composition solution containing no titanium chelate was prepared, the test was carried out by the method described below, and the results are shown in Table 1 together with Example 1. 1 is shown.

Comparative Example 3

Using the same apparatus and method as in Example 1, using a water-dispersible acrylic resin instead of a water-soluble modified polyethyleneimine-based resin to prepare a polyester film coated with a water-soluble composition solution, and then experimented by the method described below The results are shown in Table 1 together with Example 1.

Comparative Example 4

Using the same apparatus and method as in Example 1, using a water-dispersible polyester-based resin instead of a water-soluble modified polyethyleneimine-based resin to prepare a polyester film coated with a water-soluble composition, the experiment by the method described below The results are shown in Table 1 together with Example 1.

Experimental Example

The polyester film coated with the water-soluble composition liquid prepared in Examples 1 to 4 and Comparative Examples 1 to 4 was treated according to Condition 1 and Condition 2, and then the water-soluble composition applied layer faced the T-die. It is a polyolefin resin melt-extruded through a T-die at a temperature of 300 ℃ as a low density polyethylene (XL500) of Hyundai Petrochemical, ethylene vinyl acetate (Escorene Ultra) of Exxon, and the ionomer (Surlyn 1601) of DuPont 20 The surface temperature is maintained at ℃, 400mm in diameter and inserted into a cooling roll rotating at a speed of 50rpm in close contact with the pressure of the cooling roll and the nip roll by 8kgf / ㎠ and has a thickness of 30㎛ through an oscillation process A laminating sheet was obtained and shown in Table 1 by evaluating adhesion, moisture resistance and blocking resistance.

<Condition 1>

A polyester film coated with a water-soluble composition was used immediately after the preparation.

<Condition 2>

The polyester film coated with the water-soluble composition was used after exposing for 3 months in a constant temperature and humidity chamber at 23 ° C. and a relative humidity of 80%.

<Evaluation Method>

-Adhesion evaluation

Polyolefin resin-coated polyester sheet was prepared in 25 mm x 300 mm specimens, and T-peeled at a rate of 200 mm / min using an Instron UTM. The adhesive force between the ester film layer and the polyolefin-based resin layer was measured, and determined to be suitable when it is 400 g / inch or more.

-Blocking resistance evaluation

Example 1 to Example 4 and Comparative Example 1 to Comparative Example 4 The film having a thickness of 50 ㎛ prepared in Comparative Example 4 was stored for 3 days in a constant temperature and humidity chamber at a temperature of 60 ℃, 90% relative humidity, 50% relative humidity, temperature Evaluation was made according to ASTM-D-1893 at 23 ° C.

Blocking resistance (gf / 20cm) Adhesion Low Density Polyethylene and Extrusion Coating Ethylene Vinyl Acetate and Extrusion Coating Ionomer and Extrusion Coating Condition 1 Condition 2 Condition 1 Condition 2 Condition 1 Condition 2 Example 1 5.0 860 500 820 820 920 550 Example 2 5.5 860 650 820 550 920 600 Example 3 5.0 860 650 820 550 920 600 Example 4 6.0 860 600 820 500 920 500 Comparative Example 1 4.0 30 30 30 30 30 30 Comparative Example 2 150.0 650 250 800 300 900 350 Comparative Example 3 5.5 30 30 30 30 50 50 Comparative Example 4 5.0 30 30 40 40 30 30

The results measured by the reaction conditions and the test method prepared by the same method as Example 1 to Example 4 and Comparative Example 1 to Comparative Example 4 are as shown in Table 1.

In Examples 1 to 4 manufactured by the present invention, the adhesion between the polyester film and the coated polymer layer is excellent and there is no blocking between the film and the film, even when exposed at 80% relative humidity for 3 months. Compared to the initial adhesive strength it was confirmed that it has excellent moisture resistance to maintain more than 500gf / inch.

On the contrary, in Comparative Example 1, in which the water-soluble composition was not applied, blocking of the film and the film did not occur, but it was confirmed that the adhesive strength was inferior. In Comparative Example 2, in which the coupling agent was not used, the modified polyethyleneimine resin Although the initial adhesion was relatively good due to the influence, the coating film was hydrolyzed due to the influence of the hydrophilic groups remaining on the coating film after drying, resulting in poor moisture resistance and blocking.

In addition, in Comparative Example 3 and Comparative Example 4 using a water-soluble acrylic resin instead of a modified polyethyleneimine resin, there was a lack of functional groups capable of bonding with the oxidized polyolefin resin in a molten state, resulting in poor adhesion.

As described above, the present invention is one of a polyester film extruded a composition liquid consisting of a water-soluble modified polyethyleneimine resin which improves the adhesion between the polyester film and the polyolefin resin, an additive which improves moisture resistance of the resin, and water which is a polar solvent. Excellent application of the polyester film and the coated polymer layer by coating and heat setting on both sides or heat setting, without blocking of the film and the film, and maintaining the initial adhesive strength even when exposed to high humidity conditions for a long time. It is a preferred invention that can produce an inline coated polyester film having moisture resistance and lowering environmental problems and fire risk by an organic solvent.

Although the present invention has been described with reference to one embodiment, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible.

Claims (3)

A polyester film for direct extrusion coating wherein a polymer composition is applied to one side or both sides of a polyester film, comprising: a primary amine compound in which 20 to 25% is substituted with an acetyl group (-NHCOCH ₃ ) as a main component of the polymer composition; 0.01 to 5.00% by weight of a modified polyethyleneimine resin obtained by cationic polymerization of ethyleneimine produced by reacting with ketone or aldehyde as a solid content, and as a additive, a curing agent, a coupling agent, and silicon dichloride having a particle size of 0.5 μm, respectively. A water-soluble coating solution containing 0.01 to 1.00% by weight, the remainder being a polar solvent such as water, is applied before longitudinal stretching to evaporate the polar solvent by the temperature in the infrared heater and the stretching machine, or after the longitudinal stretching A polyester, which is obtained by applying a coating liquid and evaporating the solvent by the heat of the transverse stretching machine. Le film. The polyester film for direct extrusion coating according to claim 1, wherein the curing agent is an epoxy, melamine, isocyanate or aziridine-based curing agent. The polyester film for direct extrusion coating according to claim 1 or 2, wherein the coupling agent is titanate-based.