KR101520762B1 - Silicone release film and manufacturing method thereof - Google Patents

Abstract

상기 화학식 1에서, R₁, R₄, x, y, n 및 m는 명세서에서 정의한 바와 같다.The present invention relates to a silicon release film and a manufacturing method thereof.
The silicone release film of the present invention comprises a release layer formed by a silicone release agent containing a silicone oil represented by the following formula (1) on a polyester base layer, in particular, a silicone release film formed by an in- , It can be used for industrial adhesive tape such as liquid crystal display, plasma display, personal portable information terminal and navigation, organic light emitting diode and polymer light emitting diode, polarizing plate, etc. or in double-side coating or double-side adhesive field .
Formula 1

In Formula 1, R ₁ , R ₄ , x, y, n and m are as defined in the specification.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a silicone release film,

The present invention relates to a silicone release film and a method of making the same, and more particularly, to a release film formed on a polyester base layer by a silicone release agent containing a particular silicone oil, To a release film for cemented carbide while maintaining a residual adhesion rate, and a method for manufacturing the same.

Generally, the silicone release agent is composed of a silicon main chain, a silicone hardener, a silane coupling agent, a silicone surfactant, and a catalyst.

As the silicon-based material, hexenyl polysiloxane containing vinylpolysiloxane or vinyl group is mainly used. Hydrogenpolysiloxane is used as a silicone curing agent, and alkoxy group or functional group is used as a silane coupling agent. to be.

For example, Korean Patent Application No. 2010-0118164 discloses a method of adjusting the peeling force of a silicone release film using a silicone release agent. For example, in the Korean Patent Application No. 2010-0118164, an acrylic polymer- And the releasing force is controlled by forming a releasing layer including the polymeric material constituted. In Korean Patent Application No. 2005-0118821, a silicone releasing coating composition capable of controlling the releasing force is prepared by controlling the content of organopolysiloxane resin The release force of the releasing film can be controlled.

In addition to the above-mentioned invention, a release film containing a solventless silicone and a reactive modifier as a main component and having a slight peeling force has been proposed as another solution.

In general, the in-line coating technology is a technique for imparting a new function to a polyester film by coating at the same time as at least one or more axes of stretching in the course of film formation of a polyester film. By using such a coating technique, a new function is imparted to the releasable polyester film, or the conventional method of solving various problems such as a change in the peeling force with time and transfer to the adhesive layer of the releasing layer is sought.

However, in the case of the known silicone release agent, there is a limit to manufacture an inline silicone release film having a low peeling force when applied to the inline coating technology.

Accordingly, the present inventors have made efforts to improve the conventional problems, and as a result, they have found that an in-line silicone release film is provided by an in-line coating method using a silicone release agent containing a specific silicone oil in a conventional silicone release agent, And peeling force at the peeling level, thereby completing the present invention.

An object of the present invention is to provide a silicone release film in which a release layer is formed on a polyester base layer by a silicone release agent containing a specific silicone oil.

It is an object of the present invention to provide a method of manufacturing a silicone release film in which the thickness of a release layer is adjusted by an inline coating method to optimize physical properties.

In order to achieve the above object, the present invention provides a silicone release agent which is formed on a polyester base layer by a silicone release agent containing a silicone oil represented by the following formula (1) Film.

(1) Peel force, X (g / in) 15

Formula 1

(1), R ₁ to R ₄ are C ₁ to C ₁₀ alkyl, x is 30 to 500, y is 2 to 100, n and m are each an integer of 0 to 24, and the peeling force (X) The TESA 7475 tape was subjected to cyclic pressing on one side of the silicone release film and measured after one day of aging.)

In the silicone release film of the present invention, the release layer is formed by coating an aqueous silicone release agent containing an alkenyl polysiloxane, a hydrolytic polysiloxane, a silicone oil represented by the formula (1), a silicone surfactant and a platinum catalyst as solids, And is formed by coating.

At this time, the thickness of the release layer of the silicone release film of the present invention is 0.04 to 3 占 퐉.

Further, as the silicone oil represented by the formula (1) in the aqueous silicone release agent, a compound represented by the following formula (2) is more preferably used.

(2)

(Wherein x is from 30 to 500, y is from 2 to 20, and n and m are each an integer of 6).

The present invention also provides a method for producing a polyester film, comprising the steps of: 1) uniaxially stretching a polyester film, 2) applying a silicone release agent containing a silicone oil represented by the formula (1) to one or both sides of the uniaxially stretched polyester film to form a release layer And 3) biaxially stretching the polyester film on which the release layer is formed. The present invention also provides a method for producing a silicone release film by an in-line coating method.

The silicone release agent used in the production method of the present invention comprises 100 parts by weight of the alkenyl polysiloxane, 3.5 to 10 parts by weight of the hydrolytic polysiloxane, 0.001 to 10 parts by weight of the silicone oil represented by the formula (1) and 0.2 to 1.2 parts by weight of the silicone surfactant And 100 to 10,000 ppm of a catalyst composed of a compound containing platinum or platinum based on the total weight of the composition, and more specifically, the silicone release agent comprises a water-based silicone containing 1.2 to 15% by weight of solid content of the silicone release agent Release agent.

In addition, the thickness of the release layer can be optimized to 0.04 to 3 mu m by the inline coating method of the present invention.

According to the present invention, by forming a release layer on a polyester base layer by an in-line coating method, a silicone release agent containing a silicone oil component whose molecular end is substituted with an alkyl group and at least two vinyl groups are contained in the molecule, It is possible to provide a silicone release film which realizes a cemented carbide separation while maintaining the above-mentioned yield.

The present invention also provides a method for producing a silicone release film which realizes physical properties by optimizing the thickness of a release layer by an in-line coating method.

The present invention relates to a polyester base material,

A silicone release film comprising a release layer formed by a silicone release agent containing a silicone oil represented by the following formula (1), wherein the release film satisfies the following physical properties (1).

(1) Peel force, X (g / in) 15

Wherein R ₁ to R ₄ are C ₁ to C ₁₀ alkyl, x is 30 to 500, y is 2 to 100, and n and m are 0 to 24 integers, respectively.

The peeling force (X) in the present invention is based on the measured value after one-day aging after the TESA 7475 tape is cyclically pressed on one side of the silicon release film.

The silicone release agent of the present invention contains a silicone oil represented by the general formula (1) in a composition comprising a conventional alkenyl polysiloxane, a hydrotable polysiloxane, a silicone surfactant and a platinum catalyst.

In this case, the preferred content of the silicone oil is 0.001 to 10 parts by weight based on 100 parts by weight of the alkenylpolysiloxane. When the amount is less than 0.001 part by weight, it is difficult to reach the desired peel strength level. When the amount exceeds 10 parts by weight, And the stickiness and the love-off property are deteriorated.

The silicone oil represented by the general formula (1) of the present invention has a structure in which at least two vinyl groups are contained in the molecule and which is substituted with an alkyl group at the end of the molecule. The lowering of the residual adhesion rate through the vinyl group is minimized, It is possible to realize a low peel force.

Thus, the silicone oil contains at least two or more vinyl groups (y) in the molecule, preferably 2 to 100, more preferably 2 to 20. At this time, as the vinyl group in the molecule increases, the decrease in the residual adhesion rate can be minimized. However, when the number of vinyl groups in the molecule exceeds 50, the peeling force increases due to the increase in the degree of curing.

The molecular x of the silicone oil is preferably 30 to 500, and if it is less than 30, there is a problem that the peeling force is increased. If it is more than 500, the residual adhesion ratio is increased.

Accordingly, in the embodiment of the present invention, the silicone oil represented by the general formula (1) is represented by the following formula (2), but is not limited thereto.

(2)

(Wherein x is from 30 to 500, y is from 2 to 20, and n and m are each an integer of 6).

More specifically, the silicone release agent of the present invention comprises 3.5 to 10 parts by weight of a hydrogelpolysiloxane and 0.001 to 10 parts by weight of a silicone oil represented by the formula (1) based on 100 parts by weight of the alkenylpolysiloxane, 0.2 to 1.2 parts by weight of a silicone surfactant for improving tingability, and 0.1 to 6.0 parts by weight of a silane coupling agent.

In addition, the silicone release agent of the present invention preferably further comprises a catalyst comprising platinum or platinum based on the total weight of the composition in an amount ranging from 100 to 10,000 ppm. The catalyst has a hardening function. If the catalyst is less than 100 ppm, there may be a problem of uncured. On the other hand, if the amount of the catalyst is more than 10,000 ppm, there may be a problem of overcuring.

It can be seen from the above characteristics that the silicone release film of the present invention has a TESA 7475 tape standard of 15 g / in or less, more preferably 8 to 15 g / in, even more preferably, And can provide a low peel force up to 6 g / in.

That is, the silicone release film of the present invention is an inline silicone release film having a release layer of 0.04 to 3 탆 thickness formed by an inline coating method, and is an inline silicone release film having a carbide release of 15 g / in or less.

The present invention also provides a method for producing a polyester film, comprising the steps of: 1)

2) A silicone release agent containing a silicone oil represented by the general formula (1) is applied to one side or both sides of the uniaxially stretched polyester film to form a release layer,

3) A method for producing a silicone release film by an in-line coating method comprising biaxially stretching a polyester film on which the release layer is formed.

Hereinafter, steps of the manufacturing method will be described.

The substrate film used in step 1) in the method of producing the silicone release film of the present invention may be a uniaxial or biaxially oriented film having excellent productivity and processability, and the polyester film of the present invention is preferable.

As a material of the polyester film, a polyester resin such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate is described as an example, but it is to be understood that it is not limited thereto. The polyester film refers to a polyester obtained by polycondensing an aromatic dicarboxylic acid and an aliphatic glycol. The aromatic dicarboxylic acid is obtained by using terephthalic acid, 2,6-naphthalene dicarboxylic acid or the like, As the dicarboxylic acid component, isophthalic acid, phthalic acid, terephthalic acid, 2,6-naphthalene dicarboxylic acid, adipic acid, sebacic acid, oxycarboxylic acid (such as P-oxybenzoic acid) can be used. Examples of the aliphatic glycol include ethylene glycol, diethylene glycol, 1,4-cyclohexanedimethanol, propylene glycol, butanediol, neopentyl glycol and the like. The dicarboxylic acid component and the glycol component are two kinds Or more may be used in combination.

Representative examples of the polyester resin include polyethylene terephthalate (PET), polyethylene-2,6-naphthalene dicarboxylate (PEN), and copolymers containing the third component in the polyester.

The polyester resin having the above-mentioned constitution was vacuum-dried, melted by an extruder, extruded into a sheet through a T-die (DIE), adhered to the casting drum by electrostatic application (pinning) A uniaxially stretched polyester film is obtained by obtaining a polyester sheet and performing uniaxial stretching at 2.5 to 4.5 times in the roll heated to a temperature not lower than the glass transition temperature of the polyester resin by the difference in the peripheral speed between rolls and rolls .

Step 2) of the production method of the polyester release film of the present invention is a step of forming the release layer by applying the silicone release agent of the present invention one or more times to one side or both sides of the uniaxially stretched polyester film in step 1) . More specifically, the silicone release agent may be applied by a method such as a Meyer bar method or a gravure method, and a polar group may be introduced onto the surface of the film before application to improve adhesiveness between the coating layer and the film, Corona discharge can be done to improve the performance.

The composition and content of the silicone component-containing releasing agent of the present invention used in step 2) of the production method of the present invention are the same as those described above.

In this case, the silicone release agent is as described above in the silicone release film and contains a silicone oil represented by the following formula (1).

Formula 1

Wherein R ₁ to R ₄ are C ₁ to C ₁₀ alkyl, x is 30 to 500, y is 2 to 100, and n and m are 0 to 24 integers, respectively.

The silicone release agent of the present invention comprises 100 parts by weight of an alkenyl polysiloxane, 3.5 to 10 parts by weight of a hydrolytic polysiloxane, 0.001 to 10 parts by weight of a silicone oil represented by the formula (1) and 0.2 to 1.2 parts by weight of a silicone surfactant, And 100 to 10,000 ppm of a catalyst composed of platinum or a compound containing platinum. The silicone release agent may further contain 0.1 to 6.0 parts by weight of a silane coupling agent.

The silicone release agent can be applied after being diluted in a solvent before being applied to the polyester film, wherein the dilution of the silicone release composition is such that the silicone release composition has a solids content within the range of from 1.2 to 15.0% Of the silicone release agent with the solvent as the remaining amount. The solvent is not limited as long as it can be applied on a film substrate by dispersing the silicone release composition according to the present invention as a solid content, but water is preferably used. If the solid content is less than 1.2% by weight, pinholes may be formed or a uniform silicone coating layer may not be formed, so that there may be a problem of peeling off the adhesive layer after being laminated with the adhesive layer, If it is more than 15.0% by weight, a blocking phenomenon may occur between the films, resulting in damage to the appearance of the product and a change in peeling force at a high level.

In the method for producing a polyester release film of the present invention, step 3) is a step for re-casting a polyester film having a release layer formed in step 2) to prepare a biaxially oriented polyester film.

At this time, the stretching in the step 3) is performed in the direction perpendicular to the uniaxial stretching direction, and the preferred stretching ratio is 3.0 to 7.0 times. After the stretching process, the polyester release film can be produced through heat fixation, curing, drying and the like.

The thickness of the biaxially stretched polyester film produced from the production method of the present invention is 5 to 300 탆, preferably 10 to 250 탆.

Particularly, in the manufacturing method of the present invention, the thickness of the release layer is optimized to 0.04 to 3 탆 after drying by the inline coating method. At this time, if the thickness after drying of the silicone release layer is less than 0.04 mu m, there is a problem of an increase in peeling force. Conversely, if the thickness is more than 3 mu m, there is a problem such as uncured and blocking property and weak solvent resistance.

In the above, by optimizing the coating thickness of the silicone release layer in the production of the in-line coating type silicone release film and limiting the rate of change between peeling forces after a certain time elapses from the initial release force of the obtained silicone release film, Ensure appearance.

Furthermore, the silicone release film of the present invention can be applied to industrial fields such as a liquid crystal display, a plasma display, a personal digital assistant and navigation, an organic light emitting diode, a polymer light emitting diode and a polarizer, It can be usefully used in two fields of lamination process of film field and release film.

For example, when a double-sided adhesive film is laminated on a single side of a double-sided adhesive film and the silicone release film of the present invention is laminated on the back side of the double-sided adhesive film, It is possible to efficiently perform the desired work in the process.

Hereinafter, the present invention will be described in more detail with reference to Examples.

The present invention is intended to more specifically illustrate the present invention, and the scope of the present invention is not limited by these examples.

< Example  1>

Step 1: One axis Stretching  Production of polyester film

A polyethylene terephthalate pellet having an intrinsic viscosity of 0.625 dl / g containing 20 ppm of amorphous spherical silica particles having an average particle diameter of 2.5 μm was thoroughly dried at 160 ° C. for 7 hours by using a vacuum drier, - An amorphous undrawn sheet was produced by closely adhering to a cooling drum through a die by electrostatic application. This was heated again and 3.5-fold stretching was carried out at 95 ° C in the film advancing direction to prepare a uniaxially stretched polyester film. Thereafter, the film surface to be coated was subjected to a corona discharge treatment to produce a polyester film.

Step 2: Two axes Stretching  Production of polyester film

2 parts by weight of a silicone oil having 16 parts by weight of a hydrogelpolysiloxane and a vinyl group represented by the following formula 2 bonded in a branched form to 100 parts by weight of the alkenylpolysiloxane on the surface of the polyester film subjected to the corona discharge treatment, 1 part by weight of a silicone surfactant was diluted in water to prepare a silicone release agent. After coating, the coating liquid applied at a temperature of 105 to 140 캜 in a tenter section was dried, stretched 3.5 times in the direction perpendicular to the film advancing direction, and heat-treated at 200 to 250 캜 for 4 seconds to obtain a biaxially oriented polyester release film .

(2)

(Wherein x is 200, y is 15, and n and m are each an integer of 6.)

< Example  2>

A silicone release film was produced in the same manner as in Example 1 except that 5 parts by weight of silicone oil having a vinyl group represented by the formula (2) bonded in a branched form was used.

< Example  3>

A silicon release film was produced in the same manner as in Example 1, except that 10 parts by weight of a silicone oil having a vinyl group represented by the general formula (2) bonded in a branched form was used.

< Example  4>

A silicon release film was prepared in the same manner as in Example 1, except that 5 parts by weight of silicone oil having x of 200 and y of 3 in the formula (2) was bonded in a branched form.

< Example  5>

A silicone release film was prepared in the same manner as in Example 1 except that 5 parts by weight of silicone oil having a vinyl group of x = 200 and y = 7 was used in the formula (2).

< Comparative Example  1>

A silicon release film was prepared in the same manner as in Example 1 except that 10 parts by weight of a conventional unreactive silicone oil was used instead of the silicone oil having the vinyl group represented by the formula (2) bonded in a branched form.

< Comparative Example  2>

A silicon release film was produced in the same manner as in Example 1 except that silicone oil having a vinyl group represented by Chemical Formula 2 bonded in a branched form was not used.

< Experimental Example  1> Peel force  Measure

In order to measure the peeling force of the silicone release films prepared in the above Examples and Comparative Examples, the silicone release film samples obtained in each of them were coated with a standard adhesive tape (TESA7475) at 25 DEG C and 55% RH (relative humidity) Was subjected to one round reciprocating press with a load of 2 kg and then left for one day under the conditions of 25 ° C and 55% RH. Then, the peel force was measured using a measuring instrument (Chem. Instrument, product name AR-1000).

The peeling force (g / in) was calculated from the average value of five repeated measurements, with a sample size of 50 × 1,500 mm and a peel force measurement size of 250 × 1,500 mm at a 180 ° peel angle and a peel rate of 0.3 m / Respectively.

< Experimental Example  2> Residual adhesion rate  Measure

In order to measure the residual adhesion rates of the silicone release films prepared in Examples and Comparative Examples, first, a double-faced tape was used to closely contact a 50 mm × 150 mm blank film (PET) with a stainless steel plate (SUS304) ) Samples were prepared.

The coated surface of the prepared PET blank film was subjected to round-pressing once with 2 Kg of polyester adhesive tape (NITTO31B), and then kept for 30 minutes.

Thereafter, the adhesive tape was peeled off and the peel force was measured 30 seconds after the blank film (untreated surface) was subjected to reciprocating pressing once at 2 kg. At this time, the test was carried out at 25 ° C and 55% RH (A). The peel strength was measured 30 seconds after the polyester pressure-sensitive adhesive tape (NITT31B) was cyclically pressed once on the blank film (untreated surface) at 2 kg (B).

At this time, the measurement was carried out at a 180 deg. Peeling angle and a peeling rate of 0.3 m / min, and an average value of three repeated measurements was obtained to obtain a residual adhesion ratio (%).

From the measurement results, the residual adhesion rate (%) of the silicone release film was calculated as A / B x 100, and the results of the tests are shown in Table 1 below.

As can be seen from the above Table 1, the silicone release films of Examples 1 to 3 according to the present invention had low peel strength and showed no significant decrease in the residual adhesion rate.

On the other hand, in the case of Comparative Example 1 using the unreactive silicone oil instead of the silicone oil represented by the formula (1), the peeling force was evaluated at a high level, and in the case of Comparative Example 2 in which the silicone oil was not added, , And the level of peel strength was too high to achieve the target level.

Further, in the silicone oil to which the vinyl group represented by the general formula (2) was bonded in the form of branch, the residual adhesion rate was increased as the number of vinyl groups in the molecule was increased.

As described above, the present invention provides a silicone release film by forming a release layer on a polyester base layer by a specific silicone release agent by an in-line coating method.

The present invention also relates to a silicone oil composition which optimizes the silicone oil component and the content of the silicone oil component in which the molecular end is substituted with an alkyl group and contains at least two vinyl groups in the molecule and controls the thickness of the release layer formed by the in- There is provided a method of manufacturing a silicone release film which achieves cemented release while maintaining the residual adhesion ratio.

Furthermore, the silicone release film of the present invention can be applied to industrial fields such as a liquid crystal display, a plasma display, a personal digital assistant and navigation, an organic light emitting diode, a polymer light emitting diode and a polarizer, It can be usefully used in two fields of lamination process of film field and release film.

While the invention has been shown and described with reference to certain exemplary embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (8)

On the polyester base layer,
A silicone release film comprising a release layer formed by a silicone release agent containing a silicone oil represented by the following formula (1) and satisfying the following physical properties (1):
(1) Peel force, X (g / in) 15
Formula 1

In Formula 1, R ₁ to R ₄ are C ₁ to C ₁₀ alkyl, x is 30~500, y is 2~100, n and m are each an integer 1 to 24, wherein the peel force (X) is TESA It is a measurement value after 1 day of aging after 7475 tapes are cyclically pressed. The method according to claim 1, wherein the release layer comprises an aqueous silicone release agent in which the alkenyl polysiloxane, the hydrolytic polysiloxane, the silicone oil represented by the formula (1), the silicone surfactant and the platinum catalyst are contained as solid components, Wherein the silicon release film is formed by a spin coating method. The silicone release film according to claim 1, wherein the release layer is 0.04 to 3 탆 thick. The silicone release film according to claim 1, wherein the silicone oil represented by Formula 1 is a compound represented by Formula 2:
(2)

In Formula 2, x is 30 to 500, y is 2 to 20, and n and m are integers of 6, respectively. 1) A polyester film was uniaxially stretched,
2) A silicone release agent containing a silicone oil represented by the general formula (1) is applied to one side or both sides of the uniaxially stretched polyester film to form a release layer,
3) A method of producing the silicone release film of claim 1 by an in-line coating method comprising biaxially stretching a polyester film on which the release layer is formed:
Formula 1

Wherein R ₁ to R ₄ , x, y, n and m are as defined in claim 1. 6. The composition of claim 5, wherein the silicone release agent comprises 100 parts by weight of an alkenyl polysiloxane, 3.5 to 10 parts by weight of a hydrolytic polysiloxane, 0.001 to 10 parts by weight of a silicone oil represented by formula (1), and 0.2 to 1.2 parts by weight of a silicone surfactant, Wherein the catalyst comprises 100 to 10,000 ppm of a catalyst comprising platinum or platinum based on the total weight of the silicone release agent. 7. The method of claim 6, wherein the silicone release agent is a water-based silicone release agent containing a solid content of 1.2 to 15% by weight. 6. The method of claim 5, wherein the thickness of the release layer is 0.04 to 3 mu m by the in-line coating method.