KR20120056564A - Silicone release polyester film with easily controlling peeling force - Google Patents

Abstract

The present invention relates to a silicone release polyester film that is easy to control the peeling force, and more particularly, by using the microphase behavior after heat treatment to increase the peeling force to a desired level, the peeling force does not change even as time passes. The present invention relates to a silicone release polyester film which can minimize loss due to change and can easily control peeling force with less risk of environmental pollution or process. To this end, the silicone release polyester film of which the peel force can be easily adjusted according to the present invention includes a polyester base film having a thickness of 12 to 100 μm at least uniaxially stretched, and a release layer that is release coated on at least one side of the base film. The release layer is characterized in that the release layer comprises a polymeric material mainly composed of a silicone polymer and the polymer of the acrylic polymer series is composed of a water dispersion blend form.

Description

Silicone release polyester film which is easy to control peeling force {SILICONE RELEASE POLYESTER FILM WITH EASILY CONTROLLING PEELING FORCE}

The present invention relates to a silicone release polyester film that is easy to control the peeling force, and more particularly, by using the microphase behavior after heat treatment to increase the peeling force to a desired level, the peeling force does not change even as time passes. The present invention relates to a silicone release polyester film which can minimize loss due to change and can easily control peeling force with less risk of environmental pollution or process.

In general, in-line coating technology is a technology that imparts a new function to a polyester film by simultaneously coating at least one axis or more in the film forming process of a polyester film, and with the development of coating technology, double-sided simultaneous coating is also possible. . Using such a coating technique, a method has been sought to give a new function to a release polyester film or to solve various problems (such as change in peeling force over time and transfer of a release layer to an adhesive layer) in the past.

1 relates to a conventional polyester film for release, and to develop a kind and size of particles added to the polyester film currently used as a base film, the amount of oligomer precipitation after heat treatment, as well as a change in the composition of the release layer of the release film Solutions to changes in peeling time and transfer have been in progress. As an example of this development, according to Korean Patent Publication No. 2009-0073605, using small particles having a refractive index similar to that of a polyester film, which is a base film, to minimize the change of physical properties of the release coating layer by securing the processability and controlling the surface roughness of the film It is interposed about a base film.

In addition, US Patent No. 5,672,482 describes the formation of a release film using a solvent-free (aqueous) emulsion silicone in order to prevent environmental pollution by an organic solvent when forming a release layer, and to form a release film using a solvent-free emulsion silicone. Development is also taking place.

However, despite these developments, it is necessary to supplement the physical properties after forming the release layer due to the nature of the material called silicon.

In general, after the silicon coating, the silicon is cured by the following four reactions.

① curing reaction

② side reaction of catalyst

③ SiOH generation reaction

④ Secondary reaction of SiOH

The four reactions are reactions that occur when drying after silicon coating, or occur naturally over time after drying. Comparing the reaction rates of the above four reactions in the order of ①> ② ~ ③> ④. That is, the hardening reaction occurs best, but the reaction of the unreacted substances occurs due to the products of the reactions ③ and ④. In particular, ② reaction is caused by the cyclic reaction by H ₂ O from the reaction ④. These reactions cause the physical properties of the release layer to change. What is represented by the change of the physical property of a release layer is that a peeling force changes. Generally, peeling force is lowered as time goes by without any treatment on the silicon layer, but when adhesive coating or adhesive film is bonded, unreacted material meets with acrylic polymer, A sharp rise can be observed. This phenomenon causes a large difference from the initial peeling force during removal and post-processing of the release film, which has a problem inevitably disadvantageous in the production process.

On the other hand, in order to improve the peeling force and appearance characteristics of the polyester base film in relation to the prior art of the present invention by adjusting the refractive index by coextrusion technology (Korean Patent Publication No. 2008-0013869), improving the slip property and antistatic Films (Korean Patent Publication No. 2008-0035058) have been developed a lot.

Korean Patent Publication No. 2009-0073605 U.S. Patent 5,672,482 Korean Patent Publication No. 2008-0013869 Korean Patent Publication No. 2008-0035058

The present invention blends the acrylic polymer to the silicone polymer used as the main material of the polyester film release layer in order to solve the above problems and meet the conventional requirements, to the desired level using the microphase behavior after heat treatment It is possible to minimize the loss due to the change in peel force because the peel force does not change over time, and to provide a silicone release polyester film that is easy to control the peel force with less risk of environmental pollution or process.

These and other objects and advantages of the present invention will become more apparent from the following description of a preferred embodiment thereof.

The object is a film comprising a polyester base film having a thickness of at least 1 uniaxially stretched from 12 to 100 μm and a release layer coated on at least one side of the base film, wherein the release layer is based on a silicone polymer. The acrylic polymer-based polymer is achieved by a silicone release polyester film that is easy to control the peel force, characterized in that it comprises a polymer material composed of a water-disperse blend form.

Here, the silicone polymer constituting the release layer is a polymerized form including a vinyl group or a hexenyl group at the end of the polymer so that a curing reaction can occur, and the curing agent is a catalyst using platinum (Pt) or rhodium (Rh). It is done.

Preferably, the release layer is to adjust the peel force as shown in the following equation 1 according to the heating of the temperature

(1)

Peel force = (peel force of a release film having the same coating thickness) + (aT-b),

Where a = 0.41 ± 0.2, b = 1.8 ± 3, T = heat treatment temperature ( ^o C).

Preferably, the residual adhesion of the release layer is characterized in that 90% or more.

Preferably, the peel force of the release layer is characterized in that the rate of change for less than 10% for 30 days after the heat treatment.

Preferably, the coating liquid forming the release layer comprises 60 to 80% by weight of pure water, 15 to 19% by weight of a silicone-acrylic blend coating liquid, 1 to 25% by weight of an organohydroxy polysiloxane and a metal catalyst chelate coating liquid. It is characterized by.

According to the present invention, since the aqueous silicone-acrylic crude liquid is applied to at least one axially stretched transparent polyester base film, there is little risk of environmental pollution or process, and since the peeling force is stable after heat treatment, the peeling force change It can have the effect of minimizing the loss.

1 is a cross-sectional view of a conventional release polyester film.
Figure 2 is a cross-sectional view of the easy release silicone silicone polyester control film according to the invention.
Figure 3 is a cross-sectional view of the silicone release polyester film easy to control the peel force after the heat treatment according to the present invention.
4 is a peel force graph according to the temperature of Examples 1 to 3 according to the present invention.

Hereinafter, the present invention will be described in detail with reference to embodiments and drawings of the present invention. These examples are only presented by way of example only to more specifically describe the present invention, it will be apparent to those skilled in the art that the scope of the present invention is not limited by these examples. .

Silicone release polyester film easy to control the peel force according to the present invention is applied to the silicone-based polymer, such as polydimethylsiloxane (PDMS), which is a general resin used in the release layer composition by blending with the crude liquid of the acrylic polymer, In this case, the acrylic polymer on the PET base film side, the silicone polymer on the surface may have a peel force. When the coating layer is heat-treated during post-processing, the acrylic polymer, which is in close contact with the PET substrate film, moves to the matrix where the silicone polymer is formed. By using this behavior, the relative surface occupation of the silicone polymer is weakened and the peeling force is desired. The release layer can be configured to increase to a level. To this end, in the present invention, the main body constituting the coating layer was synthesized through blending of the silicone polymer and the acrylic polymer, and the peeling force of the release layer and the coating layer directly coated thereon was adjusted according to the heat treatment temperature during post-processing.

Silicone release polyester film easy to control the peel force according to the present invention is a film comprising a polyester base film having a thickness of 12 ~ 100㎛ uniaxially stretched at least, and a release layer release-release coated on at least one side of the base film As a release layer, the release layer may be formed of a silicone polymer, and the polymer may include a polymer material composed of an acrylic polymer-based polymer in the form of an aqueous dispersion blend.

The base film of the silicone release polyester film that can easily control the peel force according to the present invention is based on stretching at least one axis or more for the strength of the film, and proceeds from the inline to the release layer coating process to produce the finished product at once. Make it possible.

The silicone polymer constituting the release layer is polymerized to include a vinyl group or a hexenyl group at the end of the polymer so that a curing reaction can occur, and the curing agent is characterized by using platinum (Pt) or rhodium (Rh) as a catalyst. .

In addition, the release layer is coated with a silicone water-dispersible release coating composition, the silicone water-disperse release coating composition is an acrylic polymer is polymerized in the form of a graft or copolymer to the organo polysiloxane, organo polysiloxane resin to form an emulsion, Organohydrogen polysiloxane and a platinum chelate catalyst.

In addition, the peel force of the release layer is characterized in that the rate of change for less than 10% for 30 days after the heat treatment. This is because the acrylic polymer decreases the relative surface occupancy of silicon after heat treatment to increase the peeling force, and the change of the peeling force is small since the acrylic polymer has an effect of delaying the curing reaction mentioned at the beginning.

Specific examples of the acrylic polymer blended with the silicone polymer base material include, for example, methacrylate, hydroxy propyl acrylate, hydroxy propyl methacrylate, hydroxy ethyl acrylate, hydroxy ethyl methacrylate, 1 , 6-hexadiol diacrylate, trimethylolpropane triacrylate, trimethylolpropane ethoxylated triacrylate, trimethylolpropane methoxylated triacrylate, pentaerythritol triacrylate, dipentaerythritol hexa It synthesize | combines using the monomer characterized by one or more selected from the group which consists of an acrylate, an isobornyl methacrylate, etc.

In addition, the silicone release polyester film easy to control the peel force according to the present invention is based on stretching at least one axis or more for the strength of the film, proceeds from the inline to the release layer coating process to enable the production of finished products at once. In addition, the release layer is capable of controlling the peel force according to the heat treatment temperature of the post-processing. To this end, the peel force of the release layer is represented by the following Equation 1,

(1)

Peel force = (peel force of a release film having the same coating thickness) + (aT-b), where a = 0.41 ± 0.2, b = 1.8 ± 3, T = heat treatment temperature ( ^o C) Features (see FIG. 3).

The above equation is based on the peel force of the first release film, the value is changed according to the content of the silicone polymer constituting the release film. In general, the larger the content of silicon, the lower the peeling force, and the higher the content of the catalyst. Therefore, when the acrylic polymer is added only to the release layer having a high degree of curing with a residual adhesion of 90% or more, the variation in peeling force is lowered. In addition, in the case of the acrylic polymer improves the adhesion to the base film and does not participate in the curing reaction of the silicone polymer serves as a primer layer. Using this property, the residual adhesion of the film after release coating achieves 90% or more after heat treatment, and there is no problem due to transfer to other substrates or adhesives.

In addition, the coating liquid constituting the release layer according to the present invention includes 60 to 80% by weight of pure water, 15 to 19% by weight of a silicone-acrylic blend coating liquid, 1 to 25% by weight of an organohydroxy polysiloxane and a metal catalyst chelate coating liquid. It is preferable that the application amount of the said release layer is 0.03-20 g / m <^2> .

Hereinafter, the present invention will be described in more detail with reference to Examples. This embodiment is intended to illustrate the present invention in more detail, and the scope of the present invention is not limited to these examples.

[Example 1-3]

The crude liquid constituting the release layer of the release polyester film was prepared as the coating solution 1 below, and Examples 1, 2 and 3 were subjected to heat treatment at 100 ^° C., 120 ^° C., and 150 ^° C. for 20 seconds.

Composition of Coating Liquid 1

Pure water: 78.8 wt%

-Organopolysiloxane + hydroxy ethylacrylate: 18% by weight

-Organo polysiloxane resin + melanin curing agent: 1.2% by weight

Organohydrogen polysiloxane and platinum catalyst chelate: 2% by weight

Solid content of the entire coating solution: 7.13%, viscosity: 1.2 cps

division Silicone: Acrylic Mole Fraction Temperature Bar player Example 1 7: 3 100 4 Example 2 7: 3 120 4 Example 3 7: 3 150 4

Comparative Example 1-3

To make a coating solution in the same ratio as in the above Example, Comparative Example 1 used a resin containing no acrylic in the silicone main material, as shown in Table 2, the change in the peel force at room temperature, Comparative Examples 2 to 4 The films made in comparison 1 were heat treated at 100 ^° C., 120 ^° C. and 150 ^° C., respectively.

division Host ingredient Temperature Bar player Comparative Example 1 silicon 25 4 Comparative Example 2 silicon 100 4 Comparative Example 3 silicon 120 4 Comparative Example 4 silicon 150 4

Physical properties of the films according to Examples 1 to 3 and Comparative Examples 1 to 4 were measured through the following experimental examples, and the results are shown in Table 3 and FIG. 4.

[Experimental Example]

1. Measurement of thickness of coating layer

The coating layer thicknesses of the sheets prepared in Examples 1 to 3 and Comparative Examples 1 to 4 were measured using a micrometer-based sedimentation measuring instrument [Mitsutoyo Co., Model: ID-Ff125], and the total thickness of the sheet 10 sheets. The average value of the remaining values was obtained by subtracting the thickness of the transparent base film from the measured values.

2. Peel force measurement

The adhesive strength of the sheets prepared in Examples 1 to 3 and Comparative Examples 1 to 4 was measured by peeling 180 degrees using AR-1000 (Cheminstruments) equipment.

In the case of peeling force after 30 days, the produced film is a value of the peeling force measured after standing at room temperature for 30 days.

3. Residual adhesion rate check

Residual adhesion of the film release layer prepared in Examples 1 to 3 and Comparative Examples 1 to 4 is first attached to the release layer Nitto31B as a reference tape, left at room temperature for 30 minutes, then peeled off the tape to a general PET film 180 degree peel was measured by transferring. On the untreated film, a standard tape was dispensed and 180 degree peel was measured, and the residual adhesion rate was determined according to the ratio of the value.

Experimental results of Examples 1 to 3 and Comparative Examples 1 to 4 are shown in Table 3 and FIG. 4. In FIG. 4, the three right markers are the peeling strengths of Examples 1 to 3, and the leftmost marker is the peeling strength at room temperature of a general release film.

division Coating layer
Thickness (㎛) Initial Peeling Force
(g / in) Peel force after 30 days (g / in) Peel force change rate (%) Residual adhesion rate
(%) Example 1 0.7 32 34 5.88 92 Example 2 0.7 45 48 6.25 94 Example 3 0.7 68 71 4.22 93 Comparative Example 1 0.7 13 38 65 90 Comparative Example 2 0.7 18 62 70 95 Comparative Example 3 0.7 22 74 70 93 Comparative Example 4 0.7 23 88 73 94

As shown in Table 3 and Figure 4, when the heat treatment is peeling force is raised, in the case of peeling force after 30 days, it can be confirmed that the film subjected to the heat treatment is stable.

It is to be understood that the present invention is not limited to the above embodiments and various changes and modifications may be made by those skilled in the art without departing from the spirit and scope of the invention.

1: Polyester base film 2: Release layer
3: silicone + acrylic coating layer 3-1: silicone polymer
3-2: Acrylic Polymer

Claims (6)

In the silicone release polyester film which is easy to control the peel force,
As a film comprising a polyester base film having a thickness of at least 12 to 100㎛ uniaxially stretched, and a release layer release-coated on at least one side of the base film,
The release layer is a silicone release polyester film that is easy to control the peel force, characterized in that the silicone polymer as a main material, characterized in that it comprises a polymer material composed of an acrylic polymer-based polymer in the form of a water dispersion blend. The method of claim 1,
The silicone polymer constituting the release layer is polymerized to include a vinyl group or hexenyl group at the end of the polymer so that a curing reaction can occur, and the curing agent is characterized by using platinum (Pt) or rhodium (Rh) as a catalyst. , Silicone release polyester film which is easy to control peeling force. The method of claim 1,
The release layer is to adjust the peel force as shown in Equation 1 according to the heating of the temperature
(Equation 1)
Peel force = (peel force of a release film having the same coating thickness) + (aT-b),
Wherein a = 0.41 ± 0.2, b = 1.8 ± 3, T = heat treatment temperature ( ^o C), silicone release polyester film easy to control the peel force, characterized in that. The method of claim 1,
Residual adhesion rate of the release layer is 90% or more, the silicone release polyester film easy to control the peel force. The method of claim 1,
Peeling force of the release layer is characterized in that the rate of change for less than 10% for 30 days after the heat treatment, easy release control silicone release polyester film. The method according to any one of claims 1 to 5,
The coating liquid constituting the release layer is characterized in that it comprises 60 to 80% by weight pure water, 15 to 19% by weight of silicone-acrylic blend coating liquid, 1 to 25% by weight of organohydroxy polysiloxane and metal catalyst chelate coating liquid , Silicone release polyester film which is easy to control peeling force.

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