KR101200556B1 - Carrier film for forming green sheet - Google Patents

Abstract

The present invention relates to a carrier film for forming a green sheet, and more particularly, to improve peeling defects generated during peeling of the green sheet and the carrier film with excellent peeling properties when used as a carrier film in the green sheet forming process. It relates to a carrier film for green sheet molding. To this end, the carrier film for molding a green sheet according to the present invention is a carrier film for molding a green sheet including a polyester film and a silicone release coating layer coated with a silicone release composition on at least one surface of the polyester film. But
DH ≥ 0.2 gf / μm ² (Equation 1)
Here, "DH" is characterized in that the fine hardness value (gf / ㎛ ² ) of the surface of the silicone release coating layer.

Description

Carrier film for green sheet molding {CARRIER FILM FOR FORMING GREEN SHEET}

The present invention relates to a carrier film for forming a green sheet, and more particularly, to improve peeling defects generated during peeling of the green sheet and the carrier film with excellent peeling properties when used as a carrier film in the green sheet forming process. It relates to a carrier film for green sheet molding.

In general, MLCC (Multilayer Ceramic Capacitor) is a general-purpose core component commonly used in electronic products such as mobile phones and LCD TVs, and plays a role in flowing current required by the product.

In processing a green sheet used in such a multilayer ceramic capacitor, a silicone release film based on a polyester film is generally used as a carrier film for green sheet molding.

Recently, due to the miniaturization and thinning of electronic products, ceramic multilayer capacitors are also being miniaturized and large in capacity, and the thickness of the green sheet is gradually becoming thinner.

In order to reduce the thickness of the green sheet, the solids and the viscosity of the ceramic slurry need to be lowered, and the thin film is required to have a thin coating on the molding carrier film.

However, when the ceramic sheet is thinned and the formed ceramic sheet is peeled off from the carrier film, it should be easily peeled off even with a small force. However, the problem of peeling defects such as tearing of the thin film green sheet is generated in the existing carrier film. have.

The present invention has been made to solve the above problems, an object of the present invention is to improve the microhardness of the silicone coating film to improve the peeling defect that may occur during the peeling of the green sheet and the carrier film to improve the green sheet and the carrier It is an object of the present invention to provide a carrier film for molding a green sheet having excellent peeling properties during peeling of the film.

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 carrier film for forming a green sheet comprising a polyester film and a silicone release coating layer coated on at least one surface of the polyester film with a silicone release composition, wherein the following Formula 1 is satisfied,

DH ≥ 0.2 gf / μm ² (Equation 1)

Here, "DH" is achieved by the carrier film for green sheet molding, characterized in that the fine hardness value (gf / ㎛ ² ) of the surface of the silicone release coating layer.

In addition, the carrier film for forming the green sheet satisfies the following Equation 2,

RF ≤ 10 gf / in. (Equation 2)

Here, "RF" is characterized in that the green sheet peel force value (gf / in.) For the silicone release coating layer.

Preferably, the silicone release composition is characterized in that it comprises an alkenyl polysiloxane, hydropolysiloxane and platinum chelate catalyst.

Preferably, the silicone release composition is characterized in that it further comprises a methacryloxy silane coupling agent.

Preferably, the methacryloxy silane coupling agent is characterized in that 2 to 10% by weight compared to the alkenyl polysiloxane.

According to the present invention, when used as a carrier film in the green sheet forming process, it has an effect such as to improve the peeling failure phenomenon generated during the peeling of the green sheet and the carrier film with excellent peeling characteristics.

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. .

Carrier film for forming a green sheet according to the present invention is a carrier film for forming a green sheet comprising a polyester film and a silicone release coating layer coated with a silicone release composition on at least one surface of the polyester film, the following formula 1,

DH ≥ 0.2 gf / μm ² (Equation 1)

Here, "DH" is characterized in that the fine hardness value (gf / ㎛ ² ) of the surface of the silicone release coating layer.

Preferably, the carrier film for forming the green sheet satisfies Equation 2 below,

RF ≤ 10 gf / in. (Equation 2)

Here, "RF" is characterized in that the green sheet peel force value (gf / in.) For the silicone release coating layer.

Carrier film for forming a green sheet according to the present invention has a green hardness of the thin film and the fine hardness value (DH) of the silicon release coating layer surface is 0.2 gf / ㎛ ² or more, the green sheet peel force value for the coating layer is 10 gf / in. The following is required. In order to satisfy this, it is preferable to introduce a methacryloxy silane coupling agent into the silicone release coating layer to improve the hardness of the coating layer surface. When the fine hardness value (DH) of the surface of the silicone release coating layer according to the present invention is less than 0.2 gf / μm ² , the adhesive force between the green sheet and the silicone coating layer is increased, so that a peeling defect may occur when peeling, and the silicone release coating layer may be When the green sheet peel force value exceeds 10 gf / in., The green sheet film may be torn due to peeling defects when the green sheet is peeled off from the silicone release coating layer.

In addition, the polyester film used in the present invention is not limited in kind, but may be a known one conventionally known as a base film of silicone release coating. Although the present invention will be described with reference to polyester resins such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate and the like, the description of the silicone release composition of the present invention is not limited to polyester sheets or films. The polyester which comprises the said film refers to the polyester obtained by polycondensing aromatic dicarboxylic acid and aliphatic glycol. Examples of the aromatic dicarboxylic acid include terephthalic acid and 2,6-naphthalenedicarboxylic acid. Examples of the aliphatic glycol include ethylene glycol, diethylene glycol, 1,4-cyclohexanedimethanol and the like. Typical polyesters include polyethylene terephthalate (PET), polyethylene-2,6-naphthalenedicarboxylate (PEN), and the like. The polyester may also be a copolymer containing a third component. Examples of the dicarboxylic acid component of the copolyester include isophthalic acid, phthalic acid, terephthalic acid, 2,6-naphthalenedicarboxylic acid, adipic acid, sebacic acid, and oxycarboxylic acid (for example, P-oxybenzoic acid). Examples thereof include ethylene glycol, diethylene glycol, propylene glycol, butanediol, 1,4-cyclohexanedimethanol, neopentylglycol and the like. These dicarboxylic acid components and glycol components may use 2 or more types together. Moreover, it is preferable that the base film which concerns on this invention uses the uniaxial or biaxial oriented film which has high transparency and is excellent in productivity and workability.

In addition, the polyester film according to the present invention preferably contains particles in order to give excellent roll-to-roll running characteristics. The added particles are not particularly limited in kind as long as they can exhibit excellent slipping properties. In the present invention, silica, silicon oxide, calcium carbonate, calcium sulfate, calcium phosphate, magnesium carbonate, magnesium phosphate, barium carbonate, kaolin, aluminum oxide, titanium oxide and the like can be included. Although the shape of the particle | grains to be used is not specifically limited, Any of spherical shape, block shape, rod shape, and plate shape particle | grains can be used for this invention. In addition, there are no particular restrictions on the hardness, specific gravity and color of the particles, and two or more kinds may be used in parallel if necessary. Moreover, it is preferable that the average particle diameter of the particle | grains to be used satisfies 0.1-5 micrometers, More preferably, it is the range of 0.1-2 micrometers. If the average particle diameter is less than 0.1㎛ may cause agglomeration between particles, poor dispersion may occur, if the average particle diameter exceeds 5㎛ the surface roughness characteristics of the film may be poor coating failure during post-processing. Moreover, it is preferable to satisfy | fill 0.01-5 weight% of particle content in a polyester film, More preferably, it is the range of 0.01-3 weight%. This is because when the content is less than 0.01% by weight, the slip characteristics of the polyester film may deteriorate and the running characteristics between rolls may deteriorate. When the content is more than 5% by weight, the surface smoothness of the film may deteriorate.

In addition, the silicone release composition constituting the silicone coating layer of the carrier film for green sheet molding according to the present invention contains a methacryloxy silane coupling agent, alkoxy silane having a methacryloxy group of the following [Formula 1] is preferred.

[Formula 1]

Here, at least two of R ₁ , R ₂ , and R ₃ are hydrolyzable functional groups such as methoxy and ethoxy groups, and the rest are organic functional groups such as alkyl groups.

In addition, the silicone release composition constituting the silicone coating layer according to the present invention is an alkoxy silane (glycidoxy propyl trimethoxy silane), γ to the methacryloxy silane coupling agent Glycidoxy propyl methyl dimethoxy silane, γ-glycidoxy propyl methyl diethoxy silane, etc. may be further mixed and used.

In addition, the methacryloxy silane coupling agent according to the present invention is preferably used 2 to 10% by weight relative to the alkenyl polysiloxane used as the main chain of the silicone coating layer, when the amount is less than 2% by weight, the fine hardness of the silicone coating layer It is most preferable to set the above range because a problem that the peeling force rises due to poor appearance of the silicone coating layer and hardening of the coating layer may occur when the content exceeds 10% by weight.

In addition, the silicone release composition according to the invention is characterized in that it comprises an alkenylpolysiloxane, hydropolysiloxane and platinum chelate catalyst.

The alkenyl polysiloxane may be any type such as addition type, condensation type or ultraviolet curing type in the constitution of the silicone release composition according to the present invention, and is not particularly limited to any one type. The alkenyl polysiloxane contains an alkenyl group in a molecule, alkenyl groups may be present in any part of the molecule, and preferably at least two are present. The molecular structure may be linear or branched, or may be a structure in which both linear and branched molecules are present.

In addition, as a hardening | curing agent in the structure of the silicone mold release composition which concerns on this invention, any type, such as an addition type, condensation type, and an ultraviolet curing type, can be used, It does not specifically limit to any one. The hydropolysiloxane may be either linear, branched or cyclic, or a mixture thereof. In addition, the viscosity and molecular weight are not limited, but compatibility with the alkenyl polysiloxane should be good, and the amount of use is such that the number of hydroelectrics bonded to silicon atoms for one alkenyl group of the alkenyl polysiloxane is in the range of 1.0 to 2.0. It is preferable. If there are less than 1.0 hydrogen atoms bonded to the silicon atom for one alkenyl group of the alkenyl polysiloxane, there may be a problem in that good sclerosis may not be obtained. If the number exceeds 2.0, the elasticity or physical properties after curing may be deteriorated. Can be.

In addition, the silicone release composition according to the present invention is coated after dilution in a solvent so that the total solid content of 0.5 to 3% by weight. The solvent used for the composition is not limited as long as it can disperse the solid content of the present invention and can be applied onto a polyester film. When the total solid content of the silicone release composition is less than 0.5% by weight, a uniform silicone coating layer may not be formed, such that a problem such as tearing of the green sheet may occur when peeling from the carrier film after molding the green sheet, 3% by weight If it exceeds, the uniformity of the thickness of the green sheet may be deteriorated due to the leveling unevenness of the silicon coating layer.

The silicone coating layer according to the present invention may use a conventionally known coating method, such as bar coating, gravure coating, die coating. In addition, it may be carried out by an in-line coating method, which is a method of coating in a polyester film manufacturing process, or may be performed by an off-line coating method, which is a method of coating after a polyester film is manufactured, but is limited to any one method. It is not.

Hereinafter, the present invention will be described in detail by using examples and comparative examples of the present invention.

Example 1

5 parts by weight of hydropolypolysiloxane, 2 parts by weight of methacryloxypropyltrimethoxy silane coupling agent (Shin-Etsu Co., Ltd. product name: KBM-503) with respect to 100 parts by weight of alkenylpolysiloxane on one surface of the polyester film, 10 ppm of platinum chelate catalyst Was diluted in toluene and MEK 1: 1 solution to prepare a silicone release composition having a total solids content of 2% by weight and applied to a thickness of 10 microns. After coating, heat-treated for 20 seconds in a 180 ℃ hot air dryer to prepare a carrier film for green sheet molding.

[Example 2]

Carrier film for green sheet molding was prepared in the same manner as in Example 1, except that 5 parts by weight of methacryloxypropyltrimethoxy silane coupling agent was used.

[Example 3]

A carrier film for molding a green sheet was prepared in the same manner as in Example 1, except that 10 parts by weight of a methacryloxypropyltrimethoxy silane coupling agent was used.

Example 4

A carrier film for forming a green sheet was prepared in the same manner as in Example 1, except that 5 parts by weight of a methacryloxypropyltriethoxy silane coupling agent (trade name: KBE-503 manufactured by Shin-Etsu Co., Ltd.) was used.

Comparative Example 1

A carrier film for forming a green sheet was prepared in the same manner as in Example 1, except that 5 parts by weight of a glycidoxypropyl trimethoxy silane coupling agent (trade name: KBM-403 manufactured by Shin-Etsu Co., Ltd.) was used.

Comparative Example 2

Carrier film for green sheet molding was prepared in the same manner as in Example 1, except that 1 part by weight of methacryloxypropyltrimethoxy silane coupling agent was used.

[Comparative Example 3]

A carrier film for molding a green sheet was prepared in the same manner as in Example 1, except that 15 parts by weight of a methacryloxypropyltrimethoxy silane coupling agent was used.

Evaluation of physical properties of the films prepared in Examples 1 to 4 and Comparative Examples 1 to 3 was carried out in the same manner as shown in Table 1 below.

[Experimental Example]

[Experimental Example 1; Surface microhardness measurement]

Using a dynamic microhardness (SHIMADZU company: model name DUH-202), using a 1gf 115 ° triangular indenter was maintained for 2 seconds in the coating layer to measure the fine hardness (DH) of the coating layer.

<Micro hardness calculation formula>

DH (micro hardness, gf / μm ² ) = α (P / D ² )

Where P (gf) is the test load, D (µm) is the intrusion amount of the indenter to the sample, and α is an integer by the indenter shape (115 ° triangle pitch: 37.837)

Experimental Example 2; Green Sheet Peeling Force Measurement]

<Ceramic Composition Preparation>

To 100 parts by weight of ceramic powder (barium titanate), 5 parts by weight of binder resin (polyvinyl butyral resin) is diluted to 10 parts by weight of toluene and MEK 1: 1 mixed solvent.

<Green Sheet Manufacturing>

The ceramic composition is coated and dried on a release coating surface of a sample film with a WET thickness of 10 μm to prepare a green sheet.

Peeling Sample Preparation

The green sheet / sample film laminated sample is cut to 25 mm × 150 mm and aged at room temperature for 24 hours.

Measuring instrument: chem-instrument AR-1000

-Measurement Method: 180 ° Peeling Angle, Peeling Speed 12 in / min

-Measurement data: Peel force unit is gf / in. And the measured value is measured 5 times to calculate the average value.

Experimental Example 3; Appearance Characteristics of Green Sheet Peeling]

When peeling the green sheet from the silicone release coating layer, the appearance characteristics of the green sheet film were visually observed.

○: The green sheet film is not damaged at all.

X: Partial tear of green sheet film

division DH (gf / μm ² ) RF (gf / in.) Peeling appearance characteristics Example 1 0.236 8.63 ○ Example 2 0.384 6.81 ○ Example 3 0.592 2.54 ○ Example 4 0.401 6.74 ○ Comparative Example 1 0.093 12.42 X Comparative Example 2 0.087 15.17 X Comparative Example 3 0.681 18.67 X

As can be seen in Table 1, Examples 1 to 4 according to the present invention can be confirmed that the fine hardness of the silicon coating layer is good peeling stability for the green sheet. However, in Comparative Examples 1 and 2 where the amount of the methacryoxy silane coupling agent was not used or was not sufficient, the fine hardness of the coating layer was not sufficient. It can be seen that the peeling force is increased and the green sheet film is damaged when the green sheet is peeled off from the silicone release coating layer.

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.

Claims (5)

In the carrier film for green sheet molding,
Polyester film,
As a carrier film for forming a green sheet comprising a silicone release coating layer coated on at least one surface of the polyester film with a silicone release composition,
Satisfy the following equations 1 and 2,
DH ≥ 0.2 gf / μm ² (Equation 1)
RF ≤ 10 gf / in. (Equation 2)
Here, "DH" is a fine hardness value (gf / ㎛ ² ) of the surface of the silicone release coating layer, "RF" is characterized in that the green sheet peel force value (gf / in.) For the silicone release coating layer, Carrier film for green sheet molding. delete The method of claim 1,
The silicone release composition is a carrier film for green sheet molding, characterized in that it comprises an alkenyl polysiloxane, hydropolysiloxane and platinum chelate catalyst. The method of claim 3,
The silicone release composition further comprises a methacryloxy silane coupling agent, green sheet molding carrier film. 5. The method of claim 4,
The methacryloxy silane coupling agent is characterized in that used 2 to 10% by weight relative to the alkenyl polysiloxane, green sheet molding carrier film.