TWI702145B - Release film - Google Patents

Abstract

The release film (10A) is provided with a substrate (11), an antistatic layer (12) provided on the surface (11A) on one side of the substrate (11), and on the antistatic layer (12), Or the release layer (13) provided on the other side of the substrate (11), and the surface (11A) on one side of the substrate (11), the arithmetic mean roughness Ra is 15nm or less, the largest protrusion The height Rp is 150 nm or less, and the antistatic layer (12) is obtained by curing an aqueous thermosetting resin composition containing a polythiophene-based conductive polymer (A), and the thickness is 12 to 250 nm.

Description

Release film

The present invention relates to a release film with an antistatic layer, and particularly relates to a step film used in the manufacturing process of a multilayer ceramic capacitor.

In recent years, multilayer ceramic capacitors have progressed toward miniaturization and lighter weight. With this, the expectation of thinning ceramic green sheets has increased year by year, and green sheets of less than 1 μm can be manufactured. The ceramic green sheet of this kind of thin film is prone to pinholes, and the slight unevenness will become a defective product, and the yield rate tends to decrease. A ceramic green sheet is generally manufactured by coating a ceramic slurry on a release film, but in order to prevent the formation of pinholes or irregularities, a release film with high surface smoothness is required.

On the other hand, when the release film with high surface smoothness is wound into a roll shape, adhesion occurs, and defects such as electrification are likely to occur when the roll is rolled out. In order to prevent such defects, it is known that an antistatic agent or the like is contained in a release film to impart an antistatic function.

As an antistatic agent used in release films, conductive polymers such as PEDOT-PSS (a mixture of polyethylene dioxythiophene and polystyrene sulfonate) have been used in recent years. For example, as disclosed in Patent Document 1 Generally, the release layer with a release film is formed by a release agent composition composed of a curing type silicone emulsion, a hardener, and PEDOT-PSS.

In addition, the release film is provided with an anti-static layer different from the release layer. It is known that the antistatic layer is formed by, for example, a resin composition (refer to Patent Document 2) in which a conductive polymer such as PEDOT-PSS is mixed with a polyester resin, a urethane resin, or an acrylic resin, or the like, or It is formed of a resin composition (refer to Patent Document 3) in which a conductive polymer such as PEDOT-PSS is mixed with a light-curing coating agent.

[Prior technical literature] 〔Patent Literature〕

Patent Document 1: Japanese Patent Application Publication No. 2003-251756

Patent Document 2: JP 2012-224011 A

Patent Document 3: Japanese Patent Application Publication No. 2010-6079

However, as in Patent Document 1, when PEDOT-PSS is formulated in the release agent composition, the polysiloxane emulsion of the release agent component has poor compatibility with PEDOT-PSS, which easily causes the PEDOT-PSS to aggregate into coarse protrusions. Therefore, it is difficult to smooth the surface of the release film. In addition, the resin composition described in Patent Document 3, PEDOT-PSS, also tends to aggregate, and it is difficult to ensure the surface smoothness of the antistatic layer and the release layer formed on the antistatic layer.

On the other hand, the resin composition described in Patent Document 2 is Cross-linking type, so it cannot be sufficient film strength, etc., and it is easy to produce the solvent resistance of the antistatic layer or the coating property of the antistatic layer, that is, the coating solution of the release layer formed on the antistatic layer Defects such as deterioration of coatability.

The present invention was completed in view of the above problems, and the subject is to provide a release film with a smooth surface and excellent antistatic properties, solvent resistance, and coating properties.

As a result of active review, the inventors found that by containing a polythiophene-based conductive polymer such as PEDOT-PSS, a water-based and thermosetting resin composition, a specific thickness of anti-corrosion layer is formed on a smooth substrate surface. The electrostatic layer can solve the above-mentioned problems and complete the following invention. That is, the present invention provides the following (1) to (9).

(1) A release film comprising a substrate, an antistatic layer provided on one side of the substrate, and a surface on the antistatic layer or on the other side of the substrate The release layer provided on the above substrate, and the surface on one side of the aforementioned substrate, the arithmetic average roughness Ra is 15nm or less, the maximum protrusion height Rp is 150nm or less, and the antistatic layer will contain polythiophene with high conductivity Molecule (A) is obtained by curing the water-based thermosetting resin composition, and the thickness of the antistatic layer is 12~250nm.

(2) The release film of (1) above, wherein the release layer is provided on the antistatic layer.

(3) The release film of (1) or (2) above, wherein the aforementioned release film The arithmetic average thickness of the layer Ra is less than 10 nm, and the maximum protrusion height Rp is less than 100 nm.

(4) The release film of any one of (1) to (3) above, wherein the aqueous thermosetting resin composition further contains a hydroxyl-containing polyester resin (B) and a melamine compound (C) .

(5) The release film according to the above (4), wherein the aforementioned water-based thermosetting resin composition is based on a total of 100 masses of the polythiophene-based conductive polymer (A) and the hydroxyl-containing polyester resin (B) In terms of parts, it contains 8 to 35 parts by mass of the melamine compound (C).

(6) The release film according to (4) or (5) above, wherein the aqueous thermosetting resin composition contains 0.5-50 mass parts relative to 100 mass parts of hydroxyl-containing polyester resin (B) Parts of polythiophene-based conductive polymer (A).

(7) The release film according to any one of (4) to (6) above, wherein the melamine compound (C) is methylol melamine.

(8) The release film of any one of (1) to (7) above, wherein the aforementioned polythiophene-based conductive polymer (A) is a mixture of polyethylene dioxythiophene and polystyrene sulfonate (PEDOT -PSS).

(9) The release film of any one of (1) to (8) above is used in the manufacturing step of ceramic green sheets.

The present invention can provide a release film with a smooth surface and excellent antistatic properties, solvent resistance and coating properties.

10A、10B‧‧‧Release film

11‧‧‧Substrate

11A‧‧‧One side surface

12‧‧‧Anti-static layer

13‧‧‧Release layer

Fig. 1 is a schematic cross-sectional view showing an embodiment of the release film of the present invention.

Fig. 2 is a schematic cross-sectional view showing another embodiment of the release film of the present invention.

Hereinafter, the embodiments of the present invention will be described in detail.

The release film of the present invention includes a substrate, an antistatic layer provided on one side of the substrate, and a release film provided on the antistatic layer or on the other side of the substrate Layerer.

More specifically, as a release film, for example, as shown in FIG. 1, a base material 11, an antistatic layer 12 provided on a surface 11A on one side of the base material 11, and an antistatic layer 12 The release film 10A of the release layer 13 provided on it, but can also be as shown in FIG. 2, the antistatic layer 12 is provided on the surface 11A on one side of the substrate 11 while the release layer 13 is provided on the substrate Release film 10B on surface 11B on the other side of 11.

When the release film is wound into a roll, adhesion may occur depending on the situation, and static electricity will be generated when the release film is rolled out of the roll. The release film has an anti-static layer to prevent the electrification when it is rolled out, which can prevent adhesion or decrease in rollability. In addition, when various articles such as ceramic green sheets laminated on the release layer are peeled from the release film, it is not easy to cause peeling failure due to electrification. Furthermore, it can also prevent Prevents dust from adhering to the release layer due to static electricity.

As the release film, as shown in FIG. 1, the release layer 13 is preferably provided on the antistatic layer 12. In this type of release film, the antistatic layer 12 can easily further prevent charging on the release layer 13.

Secondly, each component of the release film will be described in detail.

〔Substrate〕

The substrate is a surface (surface 11A in Figs. 1 and 2) on one side of the substrate on which the antistatic layer is formed. The arithmetic mean roughness Ra is 15 nm or less, and the maximum protrusion height Rp is 150 nm or less. In the present invention, when the arithmetic average roughness Ra or the maximum protrusion height Rp of one side surface of the substrate exceeds these upper limits, even if the composition for forming the antistatic layer is the aqueous thermosetting resin composition described later, It is also difficult to smooth the surface of the antistatic layer. When the surface of the antistatic layer is not smooth, for example, when a film such as a release layer is provided on the antistatic layer, the surface of the release layer, etc., is not smooth, and the ceramic green sheet formed on the release layer is easy to produce Bumps or pinholes.

From the above viewpoints, the arithmetic average roughness Ra and the maximum protrusion height Rp are preferably 12 nm or less and 120 nm or less, respectively. In addition, considering the ease of manufacture of the substrate, the arithmetic average roughness Ra and the maximum protrusion height Rp are preferably 1 nm or more and 5 nm or more, respectively.

As the substrate, if the arithmetic average roughness Ra and the maximum protrusion height Rp are in the above range, there are no particular restrictions. Examples include polyesters such as polyethylene terephthalate or polyethylene naphthalate, and polypropylene Or polyolefins such as polymethylpentene, polycarbonate, polyvinyl acetate and other plastics The formed film can be a single layer, or multiple layers of two or more layers of the same or different species. Among these, a polyester film is preferred, and a polyethylene terephthalate film is particularly preferred. Since the polyethylene terephthalate film is less likely to generate dust during processing, use, etc., it can effectively prevent, for example, poor ceramic slurry coating caused by dust.

In addition, the thickness of the base material is not particularly limited, but is usually 10 to 300 μm, preferably about 15 to 200 μm.

In order to ensure the arithmetic average thickness Ra and the maximum protrusion height Rp, the base material preferably does not contain particles. However, as long as the above-mentioned arithmetic average thickness Ra and the maximum protrusion height Rp can be ensured, the substrate may contain particles. When particles are contained, in order to reduce the arithmetic average roughness Ra and the maximum protrusion height Rp of the substrate, it is only necessary to reduce the particle size of the particles (for example, fillers such as silica, calcium carbonate, and titanium oxide to impart slipperiness) , Just reduce the amount of the particles.

〔Anti-static layer〕

The antistatic layer is obtained by curing an aqueous thermosetting resin composition containing a polythiophene-based conductive polymer (A) (hereinafter also simply referred to as (A) component).

In the present invention, since the resin composition forming the antistatic layer is thermosetting, the film strength of the antistatic layer is increased, so the solvent resistance of the antistatic layer is good. Furthermore, when a thin layer such as a release layer is provided on the antistatic layer, the coating property of the outer coating of the thin layer is good. That is, when a thin layer such as a release layer is formed on the antistatic layer, uneven coating can be prevented, and repelling or streaks can be prevented.

In addition, by making the composition water-based, the polythiophene-based conductive polymer (A) is easily dispersed or dissolved without agglomeration, etc. in the composition, so that the antistatic layer or the release layer formed on it can be obtained smooth. Furthermore, it prevents the release layer formed on the antistatic layer from producing unevenness or pinholes.

In addition, the thickness of the antistatic layer is 12 to 250 nm. When the thickness of the antistatic layer is less than 12nm, the thickness is too thin, and the surface resistance of the antistatic layer cannot be sufficiently reduced by the component (A), and it is difficult to impart antistatic performance. In addition, a sufficient film cannot be formed, and solvent resistance or overcoatability becomes low. On the other hand, when it is larger than 250 nm, even if one side of the substrate is a smooth surface, it is difficult to smooth the surface of the antistatic layer, and it is difficult to ensure the surface smoothness of the release layer formed on the antistatic layer. Based on the above viewpoints, the thickness of the antistatic layer is preferably 15 to 200 nm. In addition, the thickness of the antistatic layer was measured using a spectroscopic ellipsometer.

In addition, the antistatic layer can have a desired thickness by appropriately changing the solid content concentration in the aqueous thermosetting resin composition, changing the gap of the coating device, and the like. The solid content concentration in the water-based thermosetting resin composition is not particularly limited, but it is preferably about 0.4 to 2.0% by mass, more preferably about 0.5 to 1.6% by mass.

The antistatic film is preferably made of a cured film formed by cross-linking a polyester resin and a melamine compound. Specifically, it is preferable to include a hydroxyl-containing polyester resin (B) in addition to the above-mentioned component (A) ( Hereinafter, it is also abbreviated as polyester resin (B) or (B) component) and melamine compound (C) (hereinafter also abbreviated as (C) component) by curing a water-based thermosetting resin composition.

In addition, the aqueous thermosetting resin composition may be water-dispersible or water-soluble by dispersing or dissolving each component in a diluent containing water.

Hereinafter, the components constituting the antistatic layer will be described in more detail.

<Polythiophene-based conductive polymer (A)>

Examples of specific compounds of the polythiophene-based conductive polymer (A) are polyalkylene dioxythiophene and polystyrene sulfonate such as polyethylene dioxythiophene, polypropylene dioxythiophene, poly(ethylene/propylene) dioxythiophene, etc. A mixture of acid esters; polythiophene compounds with sulfonic acid groups such as poly(3-thiophene-β-ethanesulfonic acid). Among them, a mixture of polyalkyldioxythiophene and polystyrene sulfonate is preferred, and a mixture of polyethylene dioxythiophene and polystyrene sulfonate (PEDOT-PSS) is more preferred.

By containing the polythiophene-based conductive polymer (A) in the antistatic agent, the surface resistance value can be sufficiently reduced even if it is a thin film, and charging can be effectively prevented. Furthermore, the polythiophene-based conductive polymer (A) has water-soluble and water-dispersible properties, and therefore, as described above, can be easily dissolved or dispersed in the water-based thermosetting resin composition.

The water-based thermosetting resin composition for forming the antistatic layer preferably contains 0.5-50 parts by mass of the polythiophene-based conductive polymer (A) relative to 100 parts by mass of the polyester resin (B). When the component (A) contains the above lower limit or more, the release film can exhibit proper antistatic performance. And by being below the upper limit value, the (A) component can be prevented from agglomerating and causing poor curing of the antistatic layer.

Based on the above point of view, in the aqueous thermosetting resin composition, the (A) component is more preferably contained in 0.6 to 20 parts by mass relative to 100 parts by mass of the (B) component.

<Polyester resin (B)>

The polyester resin (B) is obtained by reacting a polycarboxylic acid component and a polyol component. The polyester resin (B) contains hydroxyl groups in its molecule, and the equivalent ratio (OH group/COOH group) of the OH group of the alcohol component of the polyester to the COOH group of the polycarboxylic acid component is preferably greater than 1.0. The polyester resin (B) can be crosslinked with the melamine compound (C) by containing a hydroxyl group.

Here, the polycarboxylic acid component is a compound having two or more carboxyl groups in one molecule. For example, phthalic acid, isophthalic acid, terephthalic acid, tetrahydrophthalic acid, and tetrahydroisophthalic acid can be used. , Tetrahydroterephthalic acid, hexahydrophthalic acid, hexahydroisophthalic acid, hexahydroterephthalic acid, trimellitic acid, adipic acid, sebacic acid, succinic acid, azaleaic acid, naphthalene Manufacturing of polyester resins such as dicarboxylic acid, 4,4-diphenyldicarboxylic acid, hexachloronorbornene dicarboxylic acid (HET acid), fumaric acid, maleic acid, itaconic acid, pyromellitic acid, etc. Polybasic acid that can be used in general. Moreover, as a polyhydric carboxylic acid component, you may use the acid anhydride of the said polyhydric carboxylic acid component. These polyvalent carboxylic acid components can be used individually or in combination of 2 or more types.

The polyol component is a compound having two or more hydroxyl groups in one molecule, and specific examples thereof are ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, polyethylene glycol, and poly Propylene glycol, new Pentylene glycol, hexanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 2-butyl-2-ethyl- Diols such as 1,3-propanediol, methylpropanediol, cyclohexanedimethanol, 3,3-diethyl-1,5-pentanediol, glycerin, trimethylolethane, trimethylol It is usually used in the production of polyester resins such as propane, erythritol, pentaerythritol, dipentaerythritol and other alcohols with trivalent or higher. These polyol components can be used individually or in combination of 2 or more types.

The polyester resin (B) is preferably water-soluble or water-dispersible in order to be a component of the water-based thermosetting resin composition. The polyester resin (B) is not particularly limited, but in order to impart water solubility or water dispersibility, it is preferable to use a structural unit containing a sulfonate group or a carboxylate group as a structural unit of the polyester.

In addition, the polyester resin (B) is the main component in the water-based thermosetting resin composition, and it usually contains 50% by mass or more of the total solid content in the composition, preferably 65 to 92% by mass. In this specification, the term "total solid content" refers to the amount of volatile components such as solvents volatilized during the manufacturing process such as the curing step, which are removed from the aqueous thermosetting resin composition.

<Melamine Compound (C)>

In addition, specific examples of the melamine compound (C) are methylol melamine or alkoxylated methylol melamine, but in terms of high water solubility and fast heat curing speed, methylol melamine is more preferable. In addition, methylol melamine is exemplified by one in which 1 to 6 methylol groups are bonded to the nitrogen atom of the amino group of melamine. In addition, alkoxylated methylol melamine is exemplified by methylol tri At least part of the methylol of polycyanamide is alkoxylated with lower alcohols, specific examples are methoxylated methylol melamine, butoxylated methylol melamine, etc. The carbon number of the alkoxy group is 1~ 4 persons.

In addition, the melamine compound (C) is preferably a water-soluble melamine, which is used as an aqueous solution of the above-mentioned compound.

The antistatic layer contains the component (C) in addition to the component (B), and since the polyester resin is crosslinked with the melamine compound, the above-mentioned overcoatability, solvent resistance, etc. become good.

The water-based thermosetting resin composition preferably contains 8 to 35 parts by mass of the melamine compound (C) relative to 100 parts by mass of the total of the components (A) and (B). The antistatic layer is prepared with 8 parts by mass or more of the (C) component, so that the above-mentioned solvent resistance or overcoatability is good, and the surface of the antistatic layer is easily smoothed. And by setting it to 35 parts by mass or less, the dispersion stability of the composition is good, and agglomerates are unlikely to occur.

In addition, the content of the melamine compound (C) is preferably 10 to 32 parts by mass with respect to 100 parts by mass of the total of (A) component and (B) component.

In addition, the surface resistance of the antistatic layer is preferably less than 1×10 ¹¹ Ω/□, more preferably less than 1×10 ¹⁰ Ω/□. By making the surface resistance of the antistatic layer less than 1×10 ¹¹ Ω/□, the release film can be properly prevented from being charged, and in particular, it is easy to suppress various defects that occur when the release film is used to manufacture ceramic green sheets.

The water-based thermosetting resin composition used to form the antistatic layer contains at least water as a diluting solvent, and may further contain dimethyl sulfoxide and isopropyl Polar solvents other than water such as alcohol (IPA) and ethanol are used as diluting solvents. In addition, it is more preferable to use water as the dilution solvent in which 30% by mass or more and 70% by mass or less of the total solvent are water. By setting the water to 70% by mass or less, it is less likely to cause repulsion when the water-based thermosetting resin composition is applied.

In addition, by setting water to 30% by mass or more, the component (A) can be dispersed or dissolved in the diluent, and the aggregation of the component (A) can be easily prevented. Furthermore, the water-soluble or water-dispersible (B) component and the water-soluble (C) component can be easily dispersed or dissolved in the composition. Therefore, the coating property of the thermosetting resin composition is good, and an appropriate film can be formed.

The antistatic layer is obtained by applying a water-based thermosetting resin composition obtained by diluting at least the components (A) to (C) with a diluent solvent on a substrate, and then heating and drying and thermally curing.

Here, the coating method of the water-based thermosetting resin composition is not particularly limited, and examples include, for example, gravure coating, bar coating, spray coating, spin coating, knife coating, and roll coating. Method, die nozzle coating method, etc.

In addition to the components (A) to (C) and the dilution solvent, the aqueous thermosetting resin composition may also contain resin components other than the components (A) to (C), various additives, etc., as long as the effects of the present invention are not impaired. . However, in order to ensure the smoothness of the surface of the antistatic layer, the water-based thermosetting resin composition should not contain fillers such as inorganic fillers.

〔Release layer〕

The release layer is composed of a release agent, specifically, silicone resin release agent, alkyd resin release agent, olefin resin release agent, acrylic An acrylic resin-based release agent, a rubber-based release agent, a melamine resin-based release agent, a fluororesin-based release agent, etc., but a silicone resin-based release agent is preferred. The following is a detailed description of the use of silicone resin-based release agents as release agents.

As the silicone resin-based release agent, an addition reaction type silicone resin composition is preferably used. The addition reaction type silicone resin composition is based on the main agent composed of the addition reaction type silicone resin and the cross-linking agent, with the addition of catalysts, addition reaction inhibitors, peeling regulators, and density as needed. With other additives such as enhancers, photosensitizers, etc.

The addition reaction type polysiloxane resin is not particularly limited, and various ones can be used, but for example, polyorganosiloxanes having an alkenyl group as a functional group in the molecule can be used. More specifically, vinyl or hexene can be used. Polydimethylsiloxane such as functional groups.

In addition, it is also possible to use a linear polyorganosiloxane having an alkenyl group and having a mass average molecular weight (Mw) of 70,000 or more and a branched organic having an alkenyl group and a mass average molecular weight (Mw) of about 500 to 50,000. The silicone oligomer mixture is used as an addition reaction to perform polysiloxane resin. In addition, the mass average molecular weight (Mw) in this specification means a value obtained by gel permeation chromatography (GPC) in terms of polystyrene.

The crosslinking agent is exemplified by polyorganosiloxane having at least two hydrogen atoms bonded to silicon atoms in one molecule, and a specific example is polymethylhydrosiloxane. The use amount of the crosslinking agent is selected within the range of 100 parts by mass of the addition reaction type polysiloxane tree, preferably 0.1-100 parts by mass, more preferably 0.5-25 parts by mass. And as the catalyst system, a platinum-based catalyst is used.

The release layer is used to prevent unevenness or pinholes from the ceramic green sheets laminated on the release layer, so the surface is preferably smooth. Specifically, it is preferable that the arithmetic average roughness Ra of the surface of the release layer is less than 10 nm and the maximum protrusion height Rp is less than 100 nm, and it is more preferable that the arithmetic average roughness Ra is 8 nm or less and the maximum protrusion height Rp is 80 nm or less. Moreover, considering the ease of manufacturing the release layer, the arithmetic average roughness Ra and the maximum protrusion height Rp are preferably 1 nm or more and 10 nm or more, respectively.

In the present invention, as described above, the arithmetic average roughness Ra and the maximum protrusion height Rp of the base material are set to a specific value or less, and the structure of the antistatic layer is set to a specific one, so that the arithmetic of the release layer formed on the antistatic layer The average thickness Ra and the maximum protrusion height Rp are reduced as described above.

As the release agent constituting the release layer, a non-solvent type or an aqueous type using water as a diluting solvent can be used, but an organic solvent is preferably used as the diluting solvent. By using solvent-based release agents, various release agents can be used in a wide range, and it is easy to design various required performances such as release performance to what is desired.

When the release agent is a solvent type, specific examples of the organic solvent used as the dilution solvent are toluene, IPA, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), and the like. Since the antistatic layer has good solvent resistance as described above, even if the release agent uses a solvent type, when the release layer is formed, defects such as dissolution of the antistatic layer can be prevented.

The release layer can be formed by coating the release agent composition on the antistatic layer or on the other side of the substrate (that is, the side on which the antistatic layer is not provided), and then heat and dry the coating film Wait for hardening to form. And release agent The coating method is not particularly limited, and examples include, for example, a gravure coating method, a bar coating method, a spray coating method, a spin coating method, a knife coating method, a roll coating method, and a die coating method.

In addition, the thickness of the release layer is not particularly limited, but it is preferably adjusted so that the weight per unit area after drying is about 0.03 to 0.4 g/m ² .

〔How to use the release film〕

The release film is better for users in the manufacturing process of multilayer ceramic capacitors, and is better used in the manufacturing process of ceramic green sheets. The ceramic green sheet is specifically produced by applying ceramic slurry on the release layer of the release film, and then appropriately drying it. In addition to the ceramic green sheet, the release film can also be used for other purposes when various materials are coated on the release layer, and the product in the shape of a sheet is made after proper curing. In addition, the ceramic green sheets or other articles made on the release film are peeled from the release film after the sheet is made.

Example

The present invention will be described in further detail below based on examples, but the present invention is not limited by these examples.

The measurement method and evaluation method of the present invention are as follows.

〔Method for measuring thickness of antistatic layer〕

The measurement was performed using a spectroscopic ellipsometer "M-2000" manufactured by J.A. Woollam Japan.

[Evaluation of surface resistance]

The surface resistance of the antistatic layer is measured by the following method.

Measuring device: "HIRESTA UP" manufactured by Mitsubishi Chemical Analysis Co., Ltd.

Measurement conditions: 100V applied voltage, 10 seconds after the measurement time, the measurement value is the average of 5 measurements

〔Evaluation of the coating properties of the antistatic layer〕

Wipe the surface of the antistatic layer formed on the substrate with a finger 10 times, and visually judge the scum (fogging) and rubbing (off) under a fluorescent lamp based on the following evaluation criteria.

A: No change B: Any of foggy or shedding

〔Evaluation of solvent resistance〕

The BEMCOT (model: AP-2) manufactured by Asahi Kasei Co., Ltd. contains an appropriate amount of solvent (MEK), and the surface of the anti-static layer formed on the substrate is about 100g/cm ² load and 1 round trip 10cm length is 1 second Wipe 20 times back and forth at a speed of left and right, and visually confirm whether the anti-static layer has fallen off under a fluorescent lamp using the following evaluation criteria.

A: No change B: Falling off.

〔Evaluation of coating properties〕

For each embodiment and comparative example, visually confirm under fluorescent light whether the surface coated with the release agent composition is on the surface due to the diluting solvent of the release agent composition Defects (whitening, unevenness or scars) in the state, or defects (repelling or streaks) in the surface state of the formed release layer. Those without the above-mentioned defects are judged as "A", and even if one type occurs, it is judged as "B".

〔Determination of surface roughness〕

The arithmetic average roughness Ra and the maximum protrusion height Rp are measured under the following conditions based on JIS B0601-1994.

Measuring device: Light interference type surface roughness meter "WYKO-1100" manufactured by Veeco

Measurement conditions: PSI mode, lens 50 magnification

[Example 1] (Formation of anti-static layer)

Diluted water-soluble hydroxyl-containing polyester resin ((B) component) 8.4 mass parts and PEDOT-PSS ((A) component) 0.5 mass parts with 15 mass parts of dimethyl sulfide and 85 mass parts of water Liquid A (manufactured by Zhongjing Oil Co., Ltd., S-495: solid content 8.2% by mass) 100 parts by mass, mixed with melamine composed of 70 parts by mass of water-soluble methylol melamine (component (C)) and 30 parts by mass of water Compound solution (manufactured by Zhongjing Oil & Fat Co., Ltd., P-795: solid content 70.0% by mass), 1.7 parts by mass, and further added with a mixed solvent of water and IPA (mass ratio 1:1), and diluted to 0.6 mass% of solid content, The coating liquid of the thermosetting resin composition is obtained.

It is made of polyethylene terephthalate film (thickness 31μm, coating liquid The coating solution of the thermosetting resin composition is uniformly coated on a substrate made of the coated surface (Ra 10nm in arithmetic average roughness and the maximum protrusion height Rp 80nm) so that the film thickness after drying becomes 15nm, Dry at 120°C for 60 seconds to form an antistatic layer.

(Formation of the release layer)

A mixture of straight-chain polyorganosiloxanes modified with trivinyl groups at both ends, branched vinyl-modified organosiloxane oligomers and polymethylhydrosiloxanes (mass average molecular weight: 287,000) diluted with MEK The solid content is 30% by mass. To 100 parts by mass of the diluent, 2 parts by mass of platinum-based catalyst (manufactured by Shin-Etsu Chemical Co., Ltd., PL-50T) were added, and the solid content concentration was adjusted to 0.7% by mass by MEK to obtain an addition reaction type polysiloxane Coating liquid for resin composition.

The obtained coating solution was uniformly coated on the antistatic layer by the bar coating method so that the film thickness after drying became 0.04 g/m ² per unit area, and then dried at 130°C for 1 minute to form a release layer. The release film of the release layer on the antistatic layer.

[Example 2]

Except for adjusting the addition amount of the mixed solvent of water and IPA (mass ratio 1:1), the solid content concentration of the coating liquid of the thermosetting resin composition is 1.5% by mass, and the thickness of the antistatic layer is 200nm, It was implemented in the same manner as in Example 1.

[Example 3]

The same procedure as in Example 1 was carried out except for changing the blending amount of the melamine compound solution to 3.5 parts by mass for 100 parts by mass of the diluent A.

[Example 4]

Except for adjusting the addition amount of the mixed solvent of water and IPA (mass ratio 1:1), the solid content concentration of the coating liquid of the thermosetting resin composition is 1.5% by mass, and the thickness of the antistatic layer is 200nm, The same procedure as in Example 3 was carried out.

[Example 5]

The same procedure as in Example 1 was carried out except that the amount of the melamine compound solution was changed to 1.45 parts by mass for 100 parts by mass of the diluent A.

[Example 6] (Formation of anti-static layer)

Diluted water-soluble hydroxyl-containing polyester resin ((B) component) 8.4 mass parts and PEDOT-PSS ((A) component) 0.5 mass parts with 15 mass parts of dimethyl sulfide and 85 mass parts of water Liquid A (manufactured by Zhongjing Oil Co., Ltd., S-495: solid content 8.2% by mass) 100 parts by mass, mixed with melamine composed of 70 parts by mass of water-soluble methylol melamine (component (C)) and 30 parts by mass of water Compound solution (Zhongjing Oil Co., Ltd., P-795: solid content 70.0% by mass) 1.7 parts by mass, and then add a mixed solvent of water and IPA (mass ratio 1:1) to dilute to 0.6 mass% of solid content to obtain a thermosetting resin Composition coating liquid.

On a substrate made of a polyethylene terephthalate film (thickness 31μm, arithmetic average roughness of the surface coated by the coating solution Ra 10nm, maximum protrusion height Rp 80nm) to make the film thick after drying The coating solution of the thermosetting resin composition was uniformly applied to a thickness of 15 nm and dried at 120°C for 60 seconds to form an antistatic layer.

(Formation of the release layer)

A mixture of straight-chain polyorganosiloxanes modified with trivinyl groups at both ends, branched vinyl-modified organosiloxane oligomers and polymethylhydrosiloxanes (mass average molecular weight: 287,000) diluted with MEK The solid content is 30% by mass. To 100 parts by mass of the diluent, 2 parts by mass of platinum-based catalyst (manufactured by Shin-Etsu Chemical Co., Ltd., PL-50T) were added, and the solid content concentration was adjusted to 0.7% by mass by MEK to obtain an addition reaction type polysiloxane Coating liquid for resin composition.

The obtained coating solution was uniformly coated on the polyethylene terephthalate film on the opposite side of the antistatic layer by the bar coating method so that the film thickness after drying became 0.04 g/m ² per unit area weight, Dry at 130°C for 1 minute to form a release layer to obtain a release film consisting of an antistatic layer and a base layer of the release layer.

[Comparative Example 1]

In addition to adjusting the addition amount of the mixed solvent of water and IPA (mass ratio 1:1), the solid content concentration of the coating liquid of the thermosetting resin composition is set to 0.5% by mass, so that the film thickness after drying becomes 10nm Except for coating, an antistatic layer was formed in the same manner as in Example 1. Subsequently, as in Example 1, a release layer was formed on the antistatic layer.

[Comparative Example 2]

In addition to adjusting the addition amount of the mixed solvent of water and IPA (mass ratio 1:1), the solid content concentration of the coating liquid of the thermosetting resin composition is set to 2.0% by mass, so that the film thickness after drying becomes 300nm Except for coating, an antistatic layer was formed in the same manner as in Example 1. Subsequently, as in Example 1, a release layer was formed on the antistatic layer.

[Comparative Example 3]

Except for adding a mixed solvent of water and IPA (mass ratio 1:1) to diluent A, it is diluted to 0.6% by mass of solid content to obtain a coating liquid of a resin composition. This resin composition system does not contain a melamine compound (C) and does not have thermosetting properties. The coating liquid of the resin composition was coated on the same substrate as in Example 1 so that the film thickness after drying became 15 nm, and dried at 120° C. for 60 seconds to form an antistatic layer. Subsequently, as in Example 1, a release layer was formed on the antistatic layer.

[Comparative Example 4]

It contains dipentaerythritol in a mass ratio of 45:20:10 75 parts by mass of acrylic monomer mixture of hexaacrylate, dipentaerythritol triacrylate and N-vinylpyrrolidone, 20 parts by mass of butyl acetate, and 30 parts by mass of IPA in 125 parts by mass of the binder solution, mixed to 1.3 The ratio of mass% contains 15.5 parts by mass of PEDOT-PSS aqueous solution and 0.2 parts by mass of α-hydroxycyclohexyl phenyl ketone (photoinitiator), and then diluted with IPA to the total amount of acrylic monomer mixture and PEDOT-PSS At 2.5% by mass, a coating liquid for a photocurable resin composition was obtained.

The coating liquid of the photocurable resin composition was uniformly coated on the same substrate as in Example 1 so that the film thickness after drying became 100nm, and after drying at 70°C for 60 seconds, the amount of light irradiated was 200mJ/cm ^2. Ultraviolet rays form an anti-static layer. Subsequently, as in Example 1, a release layer was formed on the antistatic layer.

[Comparative Example 5]

The partial hydrolysate of tetraethoxysilane (manufactured by COLCOAT, N-103X) was diluted with IPA to a solid content of 0.6% by mass to prepare a resin coating liquid. This resin coating liquid was uniformly applied on the same substrate as in Example 1 so that the film thickness after drying became 70 nm, and dried at 120° C. for 60 seconds to form an antistatic layer. Subsequently, as in Example 1, a release layer was formed on the antistatic layer.

※In Table 1, the parts by mass of (A) component (PEDOT-PSS) indicate parts by mass relative to 100 parts by mass of (B) component. (C) The mass part of the component (melamine compound) means the mass part with respect to the total of 100 mass parts of (A) component and (B) component.

In the above examples 1 to 5, the water-based thermosetting resin composition containing PEDOT-PSS is used to form an antistatic layer with a specific thickness on a smooth substrate. The release film has good antistatic performance and an antistatic layer The film has good film resistance, solvent resistance, and coating properties. In addition, since the smoothness of the surface of the antistatic layer can be ensured, the arithmetic average thickness Ra or the maximum protrusion height Rp of the release layer formed on the antistatic layer can be lowered, and the smoothness of the release layer can be ensured. Furthermore, in Example 6, a release layer is provided on the surface of the substrate opposite to the surface on which the antistatic layer is provided, but various properties can be improved.

On the other hand, the release film of Comparative Example 1 cannot have sufficient antistatic performance due to its thin antistatic layer and high surface resistance, as well as insufficient solvent resistance or overcoatability. Moreover, in Comparative Example 2, the antistatic layer is too thick, Therefore, the smoothness of the surface of the antistatic layer cannot be ensured, and the surface roughness of the release layer becomes larger.

Furthermore, in Comparative Examples 3 and 4, since the resin composition is not water-based thermosetting, the solvent resistance and the overcoatability are insufficient, and the (A) component aggregates and cannot sufficiently ensure smoothness. In addition, if the antistatic layer of the release film system of Comparative Example 5 does not contain the component (A), the antistatic layer has poor solvent resistance and overcoatability, and the surface roughness of the release layer is increased and the smoothness cannot be sufficiently ensured.

10A‧‧‧Release film

11‧‧‧Substrate

11A‧‧‧One side surface

12‧‧‧Anti-static layer

13‧‧‧Release layer

Claims (7)

A release film comprising a substrate, an antistatic layer provided on one side of the substrate, and an antistatic layer provided on the antistatic layer or on the other side of the substrate The release layer is characterized in that the arithmetic average roughness Ra of one side of the substrate is 15nm or less, the maximum protrusion height Rp is 150nm or less, and the antistatic layer contains polythiophene with high conductivity The water-based thermosetting resin composition of molecule (A) is cured, and the thickness of the antistatic layer is 12~250nm. The water-based thermosetting resin composition further contains hydroxyl-containing polyester resin (B) , And the melamine compound (C), the aforementioned water-based thermosetting resin composition, based on the total 100 parts by mass of the polythiophene-based conductive polymer (A) and the hydroxyl-containing polyester resin (B), contains 8 ~35 parts by mass of the melamine compound (C). The release film of claim 1, wherein the release layer is disposed on the antistatic layer. Such as the release film of claim 1 or 2, wherein the arithmetic average roughness Ra of the aforementioned release layer is less than 10 nm, and the maximum protrusion height Rp is less than 100 nm. The release film of claim 1 or 2, wherein the aforementioned water-based thermosetting resin composition contains 0.5-50 parts by mass of polythiophene-based conductive material relative to 100 parts by mass of hydroxyl-containing polyester resin (B)性polymer (A). Such as the release film of claim 1 or 2, in which the melamine compound (C) is methylol melamine. The release film of claim 1 or 2, wherein the aforementioned polythiophene-based conductive polymer (A) is a mixture of polyethylene dioxythiophene and polystyrene sulfonate. For example, the release film of claim 1 or 2 is used in the manufacturing steps of ceramic green sheets.

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