KR101132541B1 - Releasing film and method for preparing the same - Google Patents

Abstract

The present invention is a base film; And a release layer comprising a siloxane-containing acrylic copolymer formed on the base film.

The release film of the present invention can be usefully used in various fields including general industrial tapes and IT electronic materials.

Release film, acrylic resin, siloxane compound

Description

Release film and its manufacturing method {RELEASING FILM AND METHOD FOR PREPARING THE SAME}

The present specification relates to a modified film that can be used as a silicone adhesive release film widely used in general industrial tapes and IT electronic materials, and the like and a manufacturing method thereof.

Release agents are generally solid or liquid film forming materials used to reduce or prevent the two surfaces of the adhesive or sealant from sticking to each other. It is used in a variety of industrial processes including metal casting, food manufacturing, food packaging, polymer processing and paper coating, and is used in molded resin products, stamping foils, pressure sensitive adhesive tapes and single production. Such release agents include natural waxes, synthetic waxes, fatty acids, in particular metal salts of stearic acid and polymers such as polyvinyl alcohol, polyamides, polyolefins and silicone resins. Products obtained by coating a release agent on a film are called release films.

Silicone is superior to organic materials in heat resistance, insulation, pollution resistance, weather resistance, chemical stability, electrical properties, etc., and thus is utilized in various fields such as electronics, various industrial fields, medical fields, and health fields.

The organic adhesives are easily released from the silicone coated release film because the silicone has a lower surface tension (20-22 dyne / cm) than the organic adhesive (30 dyne / cm or more). Thus, the use of the organic adhesive in the silicone coated release film is very easy. However, when the silicone coated release film is used in the silicone adhesive, the surface tension is the same, and thus the adhesive does not release because the adhesive completely wets the release surface.

Therefore, there is a fluorosilicone coating film having a low surface tension, but this has a lot of problems that the efficiency and economic efficiency of the process is deteriorated due to expensive silicon cost, manufacturing equipment difficulties and environmental regulations.

The present invention is to solve the above problems, an object of the present invention is to solve the problem of not easily release of the conventional silicone coating release film, and to replace the fluorine coating film, while providing a release film and a method for producing the same. It is.

In order to achieve the above object, the present invention is a base film; And it provides a release film comprising a release layer comprising a siloxane-containing acrylic copolymer formed on the base film.

Moreover, this invention provides the manufacturing method of the release film characterized by forming and manufacturing the release layer containing a siloxane containing acrylic copolymer in a polyester- or polyolefin-based base film.

The release film of the present invention is colorless and has the advantage of being easy to release when peeling off the silicone pressure-sensitive adhesive, it is possible to lower the unit cost of the manufacturing equipment compared to the conventional fluorine coating film can satisfy the efficiency and economic efficiency at the same time.

Hereinafter, exemplary embodiments of the present invention will be described.

In one embodiment of the present invention, the release layer may include a copolymer of a siloxane compound and an acrylic resin containing the following [Formula 1].

Wherein each R is independently a C ₁ to C ₅ straight or branched alkyl group, C ₂ to C ₁₂ straight or branched alkenyl group, C ₆ to C ₁₂ aryl group, or hydroxy Represents a real group, and R ₂ represents an alkyn group of C ₁ to C _5. )

In one embodiment of the present invention, the release layer may include a copolymer of a siloxane compound and an acrylic resin containing the following [Formula 2].

Wherein each R is independently a C ₁ to C ₅ straight or branched alkyl group, C ₂ to C ₁₂ straight or branched alkenyl group, C ₆ to C ₁₂ aryl group, or hydroxy represents a group, R ₃ is hydrogen, hydroxyl group, C ₁ ~ C ₅ straight or branched alkyl group, C ₂ ~ C ₁₂ straight or branched alkenyl group, C ₆ ~ C ₁₂ aryl group in the R ₄ is C ₁ ~ C ₅ alkyne group.)

In one embodiment of the present invention, the release layer may include a copolymer of the siloxane compound and the acrylic resin containing the [Formula 1] and [Formula 2].

Each R in the siloxane unit is an organic group and may be the same or different.

Examples of the organic group represented by the symbol R include C ₁ to C ₅ straight or branched alkyl groups, C ₂ to C ₁₂ straight or branched alkenyl groups, C ₆ to C ₁₂ aryl groups, hydroxyl groups, and the like. These are mentioned preferably.

Wherein C may be in ₁ ~ C ₅ as a straight-chain or branched alkyl group is a methyl group, preferably an ethyl group, n- propyl group, isopropyl group, n- butyl group, an isobutyl group or a t- butyl group, More preferably, it is a methyl group or an ethyl group.

The C ~ ₂ alkenyl groups in the straight-chain or branched C ₁₂ may be preferably mentioned a vinyl group, or allyl group.

The aryl group in the C ₆ ~ C ₁₂ may be preferably mentioned a phenyl group and the like.

In addition, R ₂ may be C ₁ ~ C ₅ alkyne.

In addition, the R ₃ may be hydrogen, a hydroxyl group, a C ₁ ~ C ₅ linear or branched alkyl group, C ₂ ~ C ₁₂ linear or branched alkenyl group, C ₆ ~ C _{12 It} may be an aryl group have.

In one embodiment of the present invention, the acrylic resin has a structure derived from a (meth) acrylic acid ester represented by the following [Formula 3], and is an unsaturated carboxylic acid having one olefinic double bond and one or more carboxyl groups in a molecule thereof. It may be an acrylic resin containing a structural unit derived from the.

(Wherein R ₀ represents a hydrogen atom or a methyl group, and R ₁ represents a C ₁ to C ₁₄ alkyl group or aralkyl group which is unsubstituted or substituted with a C ₁ to C ₁₀ alkoxy group, respectively).

In this specification, (meth) acrylic acid means that any of acrylic acid or methacrylic acid may be sufficient.

In the [Formula 3], R ₀ represents a hydrogen atom or a methyl group, R ₁ is an alkyl group or an aralkyl group of C ₁ ~ C _14. Preferably an alkyl group of C ₁ ~ C ₁₀ alkyl group or aralkyl group, more preferably C ₁ ~ C ₆ alkyl group or an aralkyl group, even more preferably C ₁ ~ C ₆ of the.

The alkyl group or aralkyl group represented by R ₁ may be substituted with a C ₁ to C ₁₀ alkoxy group with hydrogen atoms in each functional group. Preferably it may be substituted by a C ₁ to C ₆ alkoxy group, more preferably C ₁ to C ₃ alkoxy group.

Specific examples of the (meth) acrylic acid esters represented by the above [Formula 3] include linear alkyl acrylates such as methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, n-octyl acrylate and lauryl acrylate; Branched alkyl acrylates, such as isobutyl acrylate, 2-ethylhexyl acrylate, and isooctyl acrylate; Linear alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, n-octyl methacrylate, and lauryl methacrylate; Branched methacrylic acid alkyl esters, such as isobutyl methacrylate, 2-ethylhexyl methacrylate, and isooctyl methacrylate, etc. are illustrated.

In addition, when R <_1> is an alkyl group substituted by the alkoxy group, ie, the (meth) acrylic acid ester represented by [Formula 3] when R <_1> is an alkoxyalkyl group, 2-methoxyethyl acrylate and ethoxymethyl acrylate are specifically, represented. , 2-methoxyethyl methacrylate, ethoxymethyl methacrylate, and the like are exemplified. Specific examples of the (meth) acrylic acid ester represented by the general formula (I) when R ₁ is an aralkyl group include benzyl acrylate and benzyl methacrylate.

As the (meth) acrylic acid ester represented by [Formula 3] during the production of the acrylic resin, any one kind of compound may be used, or two or more kinds of compounds may be used. Especially, it is preferable to use butyl acrylate as at least one monomer. Therefore, it is a preferable aspect that the structural unit derived from the (meth) acrylic acid ester which comprises a 1st acrylic resin contains the unit derived from butyl acrylate.

The unsaturated carboxylic acid serving as another structural unit of the acrylic resin is a compound having one olefinic double bond and at least one carboxyl group in the molecule, and specific examples thereof include acrylic acid, methacrylic acid, maleic acid and itaconic acid. have. Especially, acrylic acid or methacrylic acid is suitable.

The copolymer of the present invention has a polymerization degree of 100 to 2000, preferably a polymerization degree of 100 to 1500, and more preferably 200 to 1000.

In one embodiment of the present invention, the final thickness of the modified release layer coated by coating on the base film may be set according to the purpose of use, and is not particularly limited, but may be 0.01 to 3 ㎛, preferably 0.05 to 2 ㎛ More preferably, it may be 0.1 to 1.5㎛. At this time, when the thickness is less than 0.01 μm, the properties of mold release property are hard to be realized, and peeling performance is easily lowered. Moreover, it is difficult to control the surface irregularities on the surface of the release layer, which is not preferable.

In one embodiment of the present invention, the base film may be polyester-based or polyolefin-based.

In one embodiment of the present invention, the base film is polyethylene terephthalate (Poly ethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (Poly ethylene naphthalate (PEN), polybutylene naphthalate (Poly butylene naphthalate; PBN), polyethylene (poly etylene; PE) and may be made of one or more selected from the group consisting of polypropylene (Polypropylene; PP).

In one embodiment of the present invention, the thickness of the base film may be 12 μm to 250 μm, preferably 25 μm to 188 μm, and if less than 12 μm, coating of the release modified layer becomes difficult, and the thickness thereof is 250 μm. Exceeding this will increase the cost and make the work difficult.

In the manufacture of the release film of this invention, the manufacturing method of the release film characterized by forming and manufacturing the release layer containing a siloxane containing acrylic copolymer in a polyester type or a polyolefin type base film.

In an embodiment of the present invention, the release layer may be formed of a gravure coating, a micro gravure coating, a gravure coating, a comma knife coating, a roll coating, a spray coating, or a gravure coating. It may be formed by coating using one selected from (Spray) coating, Meyer Bar coating, Slot Die coating and Reverse coating machine, but is not limited thereto.

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

 [Production Example of Release Layer]

In a reactor equipped with a cooling tube, a nitrogen introduction tube, a thermometer, and a stirrer, a siloxane compound (R31, Dow Corning) and an acrylic resin (SINJ, Samyoung Ink) are mixed with toluene at a concentration of 30% by weight or more, About 3 weight part of polymerization initiators were added per 100 weight part of acrylic resins, and it stirred at about 70 degreeC for 8 hours, and manufactured the copolymer of siloxane and acryl.

 [Coating Example of Release Layer of the Present Invention]

The prepared siloxane-containing acrylic copolymer was prepared as a toluene solution having a total solid content of 15%. This solution was coated on the base film (SH71D 50㎛, manufacturer SKC) with a microgravure coating method at a wet coating amount of 6 g / m 2, followed by drying and crosslinking reaction such that the heating temperature was 100 ° C. and the heating time was 20 seconds. Prepared.

 [Evaluation of Release Force (FINAT-10)]

Silicone adhesives having adhesive strengths of 2, 20, 50, 100, 500, and 1000 (gf / in) were used as Examples 1 to 4 and Comparative Examples 1 and 2, respectively, to silicone release films, release films of the present invention, and fluorine films, respectively. After attaching, the peel force value was measured. Examples 1 to 4 and Comparative Examples 1 and 2 were pressed two times at a speed of 10 mm / sec using a FINAT test roller (2 kg load), and then 70 g / cm between specimens between flat metal plates or glass plates for sufficient compression. ^It was stored at a temperature of 2 at a temperature of 23 ± 2 ° C. for 20 hours. After storage, the pressure was removed and the test was performed after 4 hours at a temperature of 23 ± 2 ° C. In the test, Examples 1 to 4 and Comparative Examples 1 and 2 were fixed to the jig, and the silicone pressure sensitive adhesive was peeled off at a speed of 300 mm / min in an angular direction of 180 ° to measure an average value (gf / in) of the peel force. The results are shown in Table 1 below.

[Residual Adhesion (%) Measurement]

The film of the present invention (coated film) cured at 100 ° C. for 20 seconds was aged at room temperature for 2 hours, and then subjected to a load of 20 g / cm 2 with Nitto31b for 20 hours in a 70 ° C. oven. Nitto31b was attached to a Teflon sheet (coated film) and reciprocated once with a pressure rubber roller to perform the same treatment . Then, after cooling to room temperature, the tape was peeled off. In this case by measuring the peel force was defined as the initial peel strength A _0. The peeled tape was attached on the stainless plate (SUS280) cleaned with toluene in the MD direction, and reciprocated and pressed once with a pressure rubber roller. Thereafter, a load of 20 g / cm 2 was raised at room temperature and allowed to stand for 30 minutes. And teshiron was peeled off at a constant speed at a tensile speed of 0.3 m / min (180 ° angle). At this time, the peeling force was measured and defined as A. At this time, the residual adhesion rate (%) was calculated from the obtained A ₀ and A based on the following equation (1).

Residual Adhesion (%) = (A / A ₀ ) × 100

A: Peel force after treatment

A ₀ : initial peeling force

In Comparative Examples 1 and 2 of Table 1, when the release force measured value of the silicone pressure-sensitive adhesive is more than 500gf / in it can be seen that the peel force is not very effective.

Therefore, when applied to the product of 500gf / in or less, slightly peeling force than the fluorine film, but shows a very superior performance than the silicone release film, when applying the film of the present invention, while having an excellent effect, fluorine Compared to the film has the advantage that can reduce the production cost of 1/5.

And the preferable range of residual adhesiveness is usually 85% or more. When the residual adhesiveness is less than 85%, for example, when the release film is wound and stored in a roll shape, the components constituting the release layer are transferred (back-transferred) to the surface of the adjacent film, whereby properties such as wettability and peelability of the release layer become poor. It is not preferable because there are cases.

In the case of applying the film of the present invention, it can be seen that the residual adhesion rate is very excellent because the result is 95% or more.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the same is by way of illustration and example only and is not to be construed as limiting the scope of the present invention. Thus, the substantial scope of the present invention will be defined by the appended claims and equivalents thereof.

1 is a schematic view showing the structure of a release film according to an embodiment of the present invention.

* Description of the main reference numerals

10: release layer

20: base film

Claims (19)

Base film; And a release layer including a siloxane-containing acrylic copolymer formed on the base film. The release layer is a release film comprising a copolymer of a siloxane compound containing at least one selected from the group consisting of [Formula 1] and [Formula 2] and acrylic resin. [Formula 1]

[Formula 2]

Wherein each R is independently a C ₁ to C ₅ straight or branched alkyl group, C ₂ to C ₁₂ straight or branched alkenyl group, C ₆ to C ₁₂ aryl group, or hydroxy represents a group, R ₂ is C ₁ ~ C ₅ represents a group of the alkynyl group or an acrylic, R ₃ is a straight of hydrogen, hydroxyl group, C ₁ ~ C ₅ straight or branched alkyl group, C ₂ ~ C ₁₂ of A chain or branched alkenyl group, or a C ₆ to C ₁₂ aryl group, R ₄ is C ₁ ~ C ₅ alkyne group.) delete delete delete The method of claim 1, The acrylic resin is a release film characterized in that the compound represented by the following [Formula 3]. (3)

(Wherein R ₀ represents a hydrogen atom or a methyl group, and R ₁ represents a C ₁ to C ₁₄ alkyl group or aralkyl group which is unsubstituted or substituted with a C ₁ to C ₁₀ alkoxy group, respectively). The method of claim 5, The acrylic resin is methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, n-octyl acrylate, lauryl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate, isooctyl acrylate, methyl methacrylate, ethyl methacrylate. Propyl methacrylate, n-butyl methacrylate, n-octyl methacrylate, lauryl methacrylate, isobutyl methacrylate, 2-ethylhexyl methacrylate, isooctyl methacrylate, 2-methoxy acrylate Release film characterized in that it is selected from the group consisting of ethyl, ethoxy methyl acrylate, 2-methoxyethyl methacrylate, ethoxy methyl methacrylate, benzyl acrylate and benzyl methacrylate. The method according to any one of claims 1, 5 or 6, The copolymer is a release film, characterized in that the polymerization degree is 100 to 2000. The method of claim 1, The release film is characterized in that the thickness of the release layer is 0.01 to 3㎛. The method of claim 1, The base film is a release film, characterized in that the polyester-based or polyolefin-based. The method of claim 1, The base film is polyethylene terephthalate (PET), poly butylene terephthalate (PBT), polyethylene naphthalate (PEN), polypropylene (PP), polyethylene (poly Release film, characterized in that consisting of at least one selected from the group consisting of etylene (PE) and poly butylene naphthalate (PBN). The method of claim 1, The thickness of the base film is a release film, characterized in that 12 to 250 ㎛. The method of claim 1, The release film is a release film, characterized in that the adhesive force of the silicone adhesive is applied to 500gf / in or less. In the production of the release film, It is produced by forming a release layer containing a siloxane-containing acrylic copolymer in the polyester-based or polyolefin-based base film, The release layer comprises a copolymer of a siloxane compound and an acrylic resin containing at least one selected from the group consisting of the following [Formula 1] and [Formula 2]. [Formula 1]

[Formula 2]

Wherein each R is independently a C ₁ to C ₅ straight or branched alkyl group, C ₂ to C ₁₂ straight or branched alkenyl group, C ₆ to C ₁₂ aryl group, or hydroxy represents a group, R ₂ is C ₁ ~ C ₅ represents a group of the alkynyl group or an acrylic, R ₃ is a straight of hydrogen, hydroxyl group, C ₁ ~ C ₅ straight or branched alkyl group, C ₂ ~ C ₁₂ of A chain or branched alkenyl group, or a C ₆ to C ₁₂ aryl group, R ₄ is C ₁ ~ C ₅ alkyne group.) delete delete delete The method of claim 13, Said acrylic resin is a compound represented by the following [Formula 3], The manufacturing method of the release film characterized by the above-mentioned. (3)

(Wherein R ₀ represents a hydrogen atom or a methyl group, and R ₁ represents a C ₁ to C ₁₄ alkyl group or aralkyl group which is unsubstituted or substituted with a C ₁ to C ₁₀ alkoxy group, respectively). The method according to claim 13 or 17, The copolymer is a method for producing a release film, characterized in that the polymerization degree is 100 to 2000. The method of claim 13, The release layer may be formed of gravure coating, micro gravure coating, kis gravure coating, comma knife coating, roll coating, spray coating, mayor bar. Method of manufacturing a release film, characterized in that the coating is formed by using one selected from (Meyer Bar) coating, slot die coating (Slot Die) coating and Reverse coating machine (Reverser) coating machine.

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