KR102257990B1 - Anti-static release film - Google Patents

Abstract

The present invention relates to an antistatic release film and, more specifically, to an antistatic release film that simplifies the structure of the release film by integrally forming an antistatic layer and a release layer and, at the same time, improves electrical and optical properties by using different types of carbon nanotubes as a conductive material that imparts antistatic properties to the release layer.

Description

Antistatic release film {ANTI-STATIC RELEASE FILM}

The present invention relates to an antistatic release film, and more specifically, by forming an antistatic layer and a release layer integrally, the structure of the release film is simplified, and at the same time, a different kind of carbon is used as a conductive material that imparts antistatic ability to the release layer. It relates to an antistatic release film having improved electrical properties and optical properties by using nanotubes.

In general, the release film is used for the main purpose of protecting the adhesive layer (or adhesive layer), and specifically, general industrial adhesive tape, acrylic adhesive protective film, semiconductor protective film, OCA protective film for display, MLCC process film, etc. It is used in the field of electronic materials and the like. As the use of synthetic resins or synthetic fibers increases in the field of electronic materials, antistatic functions are also required in the field of release films where the function of protecting the adhesive layer is the main purpose.

In order to impart an antistatic function to the release film, a release film was developed in which an antistatic layer was laminated on the release layer, but the antistatic layer and the material forming the release layer, for example, the bonding force with the silicone compound, the bonding force between the base film and the antistatic layer, or There was a problem in that the adhesion was poor and the release film was defective.

In addition, it is difficult to implement the transparency required in the field of electronic materials, and there is a problem that the difficulty and cost of the manufacturing process are increased as the coating process of the antistatic layer and the coating process of the silicone compound are added.

An object of the present invention is to provide an antistatic release film that has a simple structure and lowers the difficulty and cost of the manufacturing process by integrally forming the conventionally separated antistatic layer and the release layer under the above technical background.

In addition, an object of the present invention is to provide an antistatic release film in which electrical and optical properties are improved by using different types of carbon nanotubes as a conductive material that imparts antistatic ability to a release layer.

In addition, an object of the present invention is to provide an antistatic release film in which a decrease in optical properties such as light transmittance and haze is minimized even when different types of carbon nanotubes are used as a conductive material that imparts antistatic ability to the release layer. .

In order to solve the above technical problem, according to an aspect of the present invention, it includes a base layer and a release layer laminated on at least one side of the base layer, wherein the release layer is a challenge that imparts antistatic ability to the release layer. As the material is included, a release film capable of implementing antistatic performance with only a single release layer without a separate antistatic layer is provided.

In one embodiment, the release layer may include a linear first conductive material having an average diameter of 3 to 10 nm and a linear second conductive material having an average diameter of 0.5 to 3 nm, and at least the first conductive material It is preferable that the average diameter of the material is larger than the average diameter of the second conductive material.

As described above, when different types of carbon nanotubes having different average diameters are used as the conductive material that imparts antistatic ability to the release layer, the density of the conductive network formed by the different types of conductive material among the release layers is improved. It is possible to improve the antistatic ability of the release layer.

In addition, in the case of the carbon nanotube, optical properties of the release layer may be affected due to physical properties such as an average diameter, an average length, and the number of outer walls. For example, as the content of the carbon nanotubes in the release layer increases, optical properties such as light transmittance and haze of the release layer may decrease.

However, in the present invention, by using different types of carbon nanotubes having different physical properties, it is possible to minimize deterioration in optical properties of the release layer and to improve electrical properties such as antistatic ability.

The antistatic release film according to the present invention simplifies the structure of the release film by integrally forming the antistatic layer and the release layer, and at the same time, by using different types of carbon nanotubes as a conductive material that imparts antistatic ability to the release layer. Electrical properties and optical properties can be improved.

In particular, in the case of using carbon nanotubes as a conductive material to implement sufficient antistatic ability in the release layer, optical properties such as light transmittance and haze of the release layer may be deteriorated, but according to the present invention, physical properties are different. By using different types of carbon nanotubes, it is possible to minimize deterioration in optical properties of the release layer and to improve electrical properties such as antistatic ability.

In addition, the silicone-based release layer may be formed by applying a one-component coating composition including polysiloxane and heterogeneous carbon nanotubes. At this time, in general, due to the low dispersibility of the carbon nanotubes, there is a concern that the miscibility with the polysiloxane in the one-component coating composition may be low, but according to the present invention, by using different types of carbon nanotubes having different physical properties, When the solid content is in the range of 3 to 60%, it is possible to ensure dispersibility to a degree that the turbiscan stability index (TSI) of the one-component coating composition can be maintained at 0.3 or less (based on 7 days).

1 schematically shows a cross-sectional structure of an antistatic release film according to an embodiment of the present invention.

Certain terms are defined herein for convenience in order to make the present invention easier to understand. Unless otherwise defined herein, scientific and technical terms used in the present invention will have the meanings generally understood by those of ordinary skill in the art. In addition, unless otherwise specified in context, terms in the singular form are to include their plural forms as well, and terms in the plural form are to be understood as including the singular form thereof.

Hereinafter, the antistatic release film according to the present invention will be described in more detail.

According to an aspect of the present invention, it includes a base layer and a release layer laminated on at least one side of the base layer, wherein the release layer includes a conductive material that imparts antistatic ability to the release layer, so that there is no separate antistatic layer. A release film capable of implementing antistatic properties with only a single release layer is provided.

The base layer is a material for maintaining the basic shape of the antistatic release film, and the type is not particularly limited, but a sheet or film formed of a material capable of forming a silicone-based release layer may be used.

More specifically, non-limiting examples of the material forming the base layer include polyester, polyethylene terephthalate, polycarbonate, polymethyl methacrylate, polyethylene naphthalate, polysulfone, polyether sulfone, cyclic olefin polymer, Resins or glasses such as triacetyl cellulose, polyvinyl alcohol, polyether ketone, polyarylate, polyimide, and polystyrene.

A release layer to which antistatic ability is provided may be positioned on at least one surface of the base layer.

The release layer is a silicone base, and may be formed by applying a one-component coating composition including polysiloxane and a different kind of conductive material to at least one surface of the base layer.

The polysiloxane used as the silicone main material (or main chain) of the one-component coating composition may be an addition type, a condensation type, or an ultraviolet curable type, and a representative structure of the polysiloxane may be represented by the following Chemical Formula 1.

[Formula 1]

Where R is each independently hydrogen, C1-C5 alkyl, C2-C10 alkenyl, C2-C10 alkynyl or hydroxy, and m and n are natural numbers equal to or greater than 0. When R is C2-C10 alkenyl, R may have a structure _{of -CH=CH 2} or -CH ₂ -CH ₂ -CH ₂ -CH ₂ -CH=CH _2.

In addition, the polysiloxane may have a linear structure as represented by Formula 1, but is not limited thereto, and may have a branched structure, or may have a structure in which a straight chain and a branched are mixed. .

In addition, the composition for one-component coating is a silicone crosslinking agent (e.g., poly(methyl hydrosine siloxane), etc.), a silicone adhesive (e.g., glycidoxypropyltrimethoxy) within the scope of the present invention. Silane, etc.), a crosslinking catalyst (eg, a platinum catalyst, etc.), a curing agent and a solvent (eg, toluene, methyl ethyl ketone, etc.).

It is preferable that the different kinds of conductive materials included in the one-component coating composition are conductive materials having different physical properties from each other.

In one embodiment, the heterogeneous conductive material included in the one-component coating composition includes a linear first conductive material having an average diameter of 3 to 10 nm and a linear second conductive material having an average diameter of 0.5 to 3 nm. In this case, it is preferable that at least the average diameter of the first conductive material is larger than the average diameter of the second conductive material.

For example, when the average diameter of the first conductive material is 3 nm, the average diameter of the second conductive material is preferably 2 nm or less, and when the average diameter of the second conductive material is 3 nm, the first conductive material It is preferable that the average diameter is 5 nm or more.

As described above, by using different types of conductive materials having different average diameters, the density of the conductive network formed by the different types of conductive materials among the release layers formed using the one-component coating composition is improved, and thus the charging of the release layer. It is possible to improve the prevention ability.

Meanwhile, it is preferable to use carbon nanotubes as the first conductive material and the second conductive material.

Carbon nanotubes are formed by combining one carbon atom with other carbon atoms around them, and a graphene sheet is rolled into a long cylindrical shape, and carbon nanotubes are generally the number of outer walls constituting carbon nanotubes. According to this, it can be classified into single-walled carbon nanotubes and multi-walled carbon nanotubes.

According to the above definition, a single-walled carbon nanotube means a carbon nanotube having one outer wall, and generally has a diameter of 0.5 nm to 3 nm. On the other hand, a multi-walled carbon nanotube means a carbon nanotube having two or more outer walls, and generally has eight or more outer walls, and has a diameter of 10 nm to 100 nm.

However, in the present application, the carbon nanotubes used as the first conductive material and the second conductive material may be defined as follows according to the number of outer walls.

The first conductive material is a carbon nanotube having 3 to 9, preferably 3 to 7 outer walls, and carbon having physical properties between the single-walled carbon nanotubes and the multi-walled carbon nanotubes. It's a nanotube. In addition, the first conductive material is a linear carbon nanotube having an average diameter of 3 to 10 nm, the average length may be 10 μm to 200 μm, the BET specific surface area is 400 m ² /g to 1,000 m ² /g I can.

In addition, the second conductive material is a carbon nanotube having less than three, preferably one outer wall, and has physical properties close to the single-walled carbon nanotubes or the single-walled carbon nanotubes described above. It's a tube. In addition, the second conductive material is a linear carbon nanotube having an average diameter of 0.5 to 3 nm, the average length may be 10 μm or less, and the BET specific surface area may be 300 m ² /g to 800 m ² /g.

On the other hand, the second conductive material has a smaller average diameter and average length compared to the first conductive material, and as the number of outer walls is small, the transparency of the one-component coating composition compared to the first conductive material, and furthermore, the one-component coating composition is used. Thus, it is possible to prevent a decrease in optical properties such as light transmittance and haze of the formed release layer. However, the dispersibility of the second conductive material in the one-component coating composition is low, and it is difficult to implement sufficient antistatic ability with the second conductive material alone, or the second conductive material in the one-component coating composition is aggregated to form the one-component coating. There is a concern that black spots may occur in the release layer formed using the coating composition.

On the other hand, the first conductive material has an advantage in terms of electron transport because the average diameter and average length are larger than that of the second conductive material, so it can be said that it is suitable for imparting antistatic ability to the release layer. However, due to the large average diameter and average length of the first conductive material, there is a problem that the density of the conductive network in the release layer is somewhat low. In addition, as the content of the first conductive material increases, there is a problem in that the transparency of the one-component coating composition, and further, optical properties such as light transmittance and haze of the release layer formed using the one-component coating composition, decrease.

Therefore, it is preferable that the weight ratio of the first conductive material and the second conductive material in the one-component coating composition is adjusted to be 1.15:1 to 5:1. When the weight ratio of the first conductive material and the second conductive material exceeds 5:1, that is, when the content of the first conductive material is excessively large compared to the second conductive material, such as light transmittance and haze of the release layer Optical properties may deteriorate. In addition, when the content of the second conductive material is excessively small compared to the first conductive material, the density of the conductive network in the release layer is low, so that sufficient antistatic ability may not be implemented.

On the other hand, when the weight ratio of the first conductive material and the second conductive material is less than 1.15:1, that is, the content of the first conductive material is excessively small compared to the second conductive material, or the second conductive material is When the content of the conductive material is excessively large, the dispersibility of the first conductive material and the second conductive material may become unstable as the relative content of the second conductive material in the one-component coating composition increases. As described above, when the first conductive material and the second conductive material are present in a non-uniform composition in the one-component coating composition, it may be difficult to obtain a release layer having uniform antistatic properties, or it may be insufficient to obtain sufficient antistatic properties. have. In addition, when the content of the second conductive material is excessively small compared to the first conductive material, the density of the conductive network in the release layer is low, so that sufficient antistatic ability may not be implemented.

In addition, it is preferable that the weight ratio of the polysiloxane and the heterogeneous conductive material (sum of the first conductive material and the second conductive material) in the one-component coating composition is in the range of 100:5 to 100:0.2.

When the heterogeneous conductive material (sum of the first conductive material and the second conductive material) is less than 0.2 parts by weight with respect to 100 parts by weight of the polysiloxane, that is, the content of the polysiloxane is excessively large compared to the different types of conductive material, or When the content of the heterogeneous conductive material is excessively small compared to the polysiloxane, there is a concern that sufficient antistatic ability may not be implemented in the release layer.

On the other hand, when the heterogeneous conductive material (sum of the first conductive material and the second conductive material) exceeds 5 parts by weight per 100 parts by weight of the polysiloxane, that is, the content of the different types of conductive material relative to the polysiloxane is excessive. Or the optical properties such as light transmittance and haze of the release layer may be deteriorated. However, in the case of a release film in which optical properties such as light transmittance and haze are not strictly required, it may also be possible to improve the antistatic ability by increasing the content of the heterogeneous conductive material compared to the polysiloxane.

The different kinds of conductive materials may be mixed with the one-component coating composition in a separately dispersed solution state, and the solution includes a dispersing agent other than the different kinds of conductive materials (low molecular weight PDMS (Mw 1,000 or less), medium molecular weight PDMS (Mw 10,000 or less) ), PVP (Polyvinylpyrrolidone), PVB (Polyvinylbutyral), pyrene-based structural compounds having hexagonal aromatic rings, pigment-friendly organic surfactants containing acrylic polymer components, imidazole-based or ammonium-based ionic liquids, etc.) and solvents (e.g. For example, toluene, methyl ethyl ketone, ethyl benzene, nucleic acid, ethyl acetate, butyl acetate, xylene, methyl isobutyl ketone, cyclohexane, benzene, isopropyl alcohol, butyl alcohol, 1-methoxy-2-propanol, etc.) And the like may be included.

While the content of the polysiloxane, the first conductive material, and the second conductive material in the one-component coating composition is within the above-described range, the solid content of the one-component coating composition is in the range of 3 to 60%, the 1 The composition for liquid coating preferably has a turbiscan stability index (TSI) of 0.3 or less (based on 7 days).

As the one-component coating composition satisfies the TSI (turbiscan stability index) of 0.3 or less (7 days) for the one-component coating composition in the range of 3 to 10% solid content, the one-component coating composition It is possible to prevent deterioration of optical properties such as light transmittance and haze of the mold release layer formed by using.

For example, the light transmittance of the release layer formed using the one-component coating composition is 85% or more, preferably 90% or more, and the haze measured according to ASTM D1003 for the release layer is 2.0% or less, preferably It may be less than 1.6%.

In this way, as the first conductive material and the second conductive material are uniformly dispersed in the polysiloxane main chain and form a dense conductive network, the release film according to the present invention, in particular, the initial surface resistance of the release layer is 10 ¹⁰ Ω May be less than or equal to /m ^2. The initial surface resistance of the release layer may be a surface resistance measured immediately after completion of the release film production or within 24 hours at the latest.

In addition, the ratio (Ω2/Ω1) of the surface resistance (Ω2) after 7 days to the initial surface resistance (Ω1) of the release layer may be less than 5, preferably less than 2, more preferably less than 1.15.

That is, not only the initial surface resistance (Ω1) of the release layer but also the surface resistance (Ω2) after 7 days have a resistance of 10 ¹⁰ Ω/m ² or less, thereby exhibiting sufficient antistatic properties, and at the same time, the initial surface of the release layer Since the change in the surface resistance (Ω2) after 7 days with respect to the resistance (Ω1) is not large, it is possible to implement stable antistatic properties for a long time.

At least one of the first conductive material and the second conductive material of the release layer may be present in a state of being silane-coupled to the polysiloxane.

To this end, a silane coupling agent for silane coupling at least one of the first conductive material and the second conductive material to the polysiloxane in the one-component coating composition may be included. More specifically, the silane coupling agent reacts with a functional group present on at least one surface of the first conductive material and the second conductive material and a functional group present on the surface of the polysiloxane to react with the first conductive material and the second conductive material. 2 Mediate chemical coupling between at least one of the conductive materials and the polysiloxane.

As the silane coupling agent, a vinyl-based silane coupling agent (for example, vinyltrimethoxysilane, vinyltriethoxysilane, etc.), an epoxy-based silane coupling agent (for example, 2-(3,4-epoxycyclohexyl) ) Ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidylpropylmethyldiethoxysilane, 3-glycidoxypropyltrie Oxysilane, etc.), a styryl-based silane coupling agent (e.g., p-styryltrimethoxysilane, etc.), a methacryloxy-based silane coupling agent (e.g., 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, etc.), acryloxy-based silane coupling agents (e.g., 3-acrylic Oxypropyltrimethoxysilane, etc.), amino-based silane coupling agent (e.g., N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-amino Propyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethylbutylidene)propylamine, N-phenyl -3-Aminopropyltrimethoxysilane, N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride, etc.), ureide-based silane coupling agents (e.g., 3-ureido Propyl trialkoxysilane, etc.), isocyanate-based silane coupling agent (eg, 3-isocyanate propyltriethoxysilane, etc.), isocyanurate-based silane coupling agent (eg, Tris- (Trimethoxysilylpropyl) isocyanurate, etc.) or a mercapto-based silane coupling agent (e.g., 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, etc.) may be used. I can.

As at least one of the first conductive material and the second conductive material is silane-coupled to the polysiloxane due to the mediation of the silane coupling agent, the release rate of the first conductive material and/or the second conductive material from the release layer is decreased. Can decrease.

The release rate of the first conductive material and/or the second conductive material from the release layer may be measured through an adhesion test of the first conductive material and the second conductive material to the release layer according to ASTM D3359-97 standard. have.

According to the present invention, the adhesion of the first conductive material and the second conductive material to the release layer may be 4B or more according to ASTM D3359-97 standard.

In addition, according to the present invention, as the first conductive material and the second conductive material are included in the release layer, a residual adhesion rate of 90%, preferably 95% or more may be exhibited. The residual adhesion to the release layer was determined by Finat test Method No. It can be measured in the same way as 11 and the like.

Hereinafter, specific embodiments of the present invention are presented. However, the examples described below are only for illustrating or explaining the present invention in detail, and the present invention is not limited thereto.

Manufacturing example. Method for producing antistatic release film

Example 1

(Step 1) Preparation of carbon nanotube dispersion

Carbon nanotubes having an average diameter of 5 nm, an average length of 200 μm, and an outer wall number of 5 are used as the first conductive material, and a carbon nanotube having an average diameter of 1.5 nm, an average length of 1.5 μm and the number of outer walls is used as the second conductive material. I did.

First, the first conductive material dispersion in which the first conductive material is dispersed was prepared as follows. The first conductive material dispersion was Naphthalene (99%, Sigmaaldrich) and TEGO Dispers 673 (EVONIK) as dispersants, toluene was used as a solvent, and the first conductive material in the first conductive material dispersion was 0.35 wt% and The dispersant was prepared to be Naphthalene 0.2 wt% and TEGO Dispers 673 0.5%. The first conductive material and the dispersant were weighed and mixed in the solvent, and then stirred at 10,000 rpm for 2 hours using a Homer mixer (model name: T 25 digital ULTRA-TURRAX, IKA).

The second conductive material dispersion in which the second conductive material is dispersed was prepared as follows. The second conductive material dispersion was made of low-viscosity silicone (Xiameter PMX-200 silicone fluid 100cSt) as a dispersant, and toluene was used as a solvent, and the second conductive material in the second conductive material dispersion was 0.3 wt% and the dispersant Was prepared to be 0.5wt%. The second conductive material and the dispersant were weighed and mixed in the solvent, and then stirred at 10,000 rpm for 4 hours using a Homer mixer (model name: T 25 digital ULTRA-TURRAX, IKA).

(Step 2) Preparation of a one-component coating composition

Toluene (purity of 99% or higher, Duksan Pharmaceutical Industries) 31 wt% and methyl ethyl ketone (purity of 99% or higher, Daejunghwa Geum) 31 wt%, polysiloxane (solid content 30 wt%, RC-3750, HRS) 18 wt% Then, a mechanical stirrer (ZZ-1000S, EYELA) was stirred at 1000 rpm for 10 minutes and dissolved.

Then, 10% of the first conductive material dispersion and the second conductive material dispersion prepared in step 1 were each added, followed by stirring at 2000 rpm for 10 minutes.

Finally, 0.2 wt% of a curing agent (CAT-04) was added, followed by stirring at 1000 rpm for 5 minutes.

In the one-component coating composition prepared as described above, the content of PDMS based on solid content was 5.0 wt%, the content of the first conductive material was 0.035 wt%, and the content of the second conductive material was 0.03 wt%.

The turbiscan stability index (TSI) for the one-component coating composition left standing for 7 days was measured to be 0.2.

The TSI for the one-component coating composition was measured using a dispersion stabilizer (Turbiscan). The dispersion stabilizer generates light with a near-infrared wavelength of 880 nm from the light source, and the intensity of light measured through a transmission detector located opposite the light source and a backscattering detector at a 45° angle of the light source. %) is measured, and it is measured by calculating as in Equation 1 below.

[Equation 1]

(Step 3) Preparation of antistatic release film

After applying the one-component coating composition prepared in step 2 to a thickness of 30 μm on a 50 μm thick PET film (substrate layer), heat treatment at 160° C. for 2 minutes to form a 1.5 μm release layer. An antistatic release film was prepared.

Example 2

Except for the use of a silane coupling agent so that 0.1 wt% of a silane coupling agent (KBM-303, Epoxy-based, Shin-Etsu Corporation) is present in the first conductive material dispersion and the second conductive material dispersion in step 1 of Example 1, respectively. And, in the same manner as in Example 1, an antistatic release film was prepared. At this time, the content of the silane coupling agent in the one-component coating composition was 0.02 wt%.

The turbiscan stability index (TSI) for the one-component coating composition used in Example 2 was measured to be 0.2.

Comparative Example 1

In step 2, the second conductive material dispersion was not used, except that the first conductive material dispersion was used alone so that the content of the first conductive material based on the solid content of the one-component coating composition was 0.065 wt%. In the same manner as in Example 1, an antistatic release film was prepared.

The turbiscan stability index (TSI) for the one-component coating composition used in Comparative Example 1 was measured to be 0.5.

Comparative Example 2

In step 2, the first conductive material dispersion was not used, except that the first conductive material dispersion was used alone so that the content of the second conductive material based on the solid content of the one-component coating composition was 0.065 wt%. In the same manner as in Example 1, an antistatic release film was prepared.

The turbiscan stability index (TSI) for the one-component coating composition used in Comparative Example 2 was measured to be 7.

Comparative Example 3

In Step 1, an antistatic release film was prepared in the same manner as in Example 1, except that carbon nanotubes having an average diameter of 10 nm, an average length of 1.5 μm, and an outer wall number of 15 were used as the first conductive material.

The turbiscan stability index (TSI) for the one-component coating composition used in Comparative Example 3 was measured as 2.

Comparative Example 4

In Step 1, an antistatic release film was prepared in the same manner as in Example 1, except that carbon nanotubes having an average diameter of 10 nm, an average length of 1.5 μm, and an outer wall number of 15 were used as the second conductive material.

The turbiscan stability index (TSI) for the one-component coating composition used in Comparative Example 4 was measured to be 0.7.

Comparative Example 5

Except for controlling the concentration of the first conductive material in the dispersion of the first conductive material so that the content of the first conductive material is 0.3 wt% based on solids in the one-component coating composition prepared in step 2 of Example 1, In the same manner as in Example 1, an antistatic release film was prepared.

The turbiscan stability index (TSI) for the one-component coating composition used in Comparative Example 5 was measured to be 0.7.

Comparative Example 6

Except for controlling the concentration of the second conductive material in the dispersion of the second conductive material so that the content of the second conductive material is 0.005 wt% based on solids in the one-component coating composition prepared in step 2 of Example 1, In the same manner as in Example 1, an antistatic release film was prepared.

The turbiscan stability index (TSI) for the one-component coating composition used in Comparative Example 6 was measured to be 0.4.

Comparative Example 7

An antistatic release film was prepared in the same manner as in Example 1, except that the carbon nanotube dispersion was not included in the one-component coating composition. In this case, the content of the first conductive material and the second conductive material in the one-component coating composition was 0 wt%, and the content of PDMS was 5 wt%.

Comparative Example 8

Conductive polymer PEDOT:PSS (Cevios P PH1000, Heraeus) and IPA (isopropyl alchol) in a ratio of 50:50 are applied to a 50 μm-thick PET film at a thickness of 10 μm, and then cured. An antistatic layer was formed, and a release layer was formed on the antistatic layer using the one-component coating composition used in Comparative Example 7 to prepare an antistatic release film.

Experimental example. Evaluation of properties of antistatic release film

The properties of the antistatic release film prepared according to the above-described Preparation Example were measured and evaluated as described below, and the results are shown in Table 1.

Release force and residual adhesion measurement method

Release force and residual adhesion rate were respectively determined by Finat test Method No. 10 (FTM10) and Finat test Method No. 11 (FTM11).

How to measure surface resistance

The surface resistance was measured at 25°C using a Hiresta-UX URS Probe, model MCP-HT800 measuring instrument (ASTM D257) from Mistubishi Chemical. At this time, the surface resistance was measured at the initial stage (immediately after completion of the release film production) and 7 days later (7 days after completion of the release film production). The surface resistance change rate was calculated as the ratio (Ω2/Ω1) of the surface resistance (Ω2) after 7 days to the initial surface resistance (Ω1).

Light transmittance and haze measurement method

Light transmittance and haze were measured using a Haze meter NDH 7000 measuring instrument (ASTM D 1003) of Nippon Denshoku, respectively.

Method of measuring adhesion of conductive material

The adhesion of the conductive material (the first conductive material and the second conductive material) to the release layer was measured according to ASTM D3359-97 standard (Cross cut adhesion test).

division Release force
(g) Residual adhesion rate
(%) Initial surface resistance
(Ω/m ² ) 7 days later
Surface resistance
(Ω/m ² ) Surface resistance
Rate of change PET film - - 10 ¹³ 10 ¹³ 1.00 Example 1 5 95.3 10 ^8.8 10 ^8.81 1.02 Example 2 5 96.1 10 ^9.0 10 ^9.0 1.07 Comparative Example 1 5 94.6 10 ^9.5 10 ^10.7 15.85 Comparative Example 2 5 94.3 10 ^8.2 10 ^8.2 1.00 Comparative Example 3 5 94.2 10 ^9.6 10 ^9.6 1.00 Comparative Example 4 5 94.7 10 ^9.0 10 ^11.1 125.89 Comparative Example 5 30 95.1 10 ^4.2 10 ^4.2 1.00 Comparative Example 6 5 92.7 10 ^10.3 10 ^11.0 5.01 Comparative Example 7 5 89.3 10 ¹³ 10 ¹³ 1.00 Comparative Example 8 5 88.7 10 ^10.3 10 ^10.3 1.00

division Light transmittance
(%) Haze
(%) Conductive material adhesion
(ASTM D3359-97) PET film 94.2 0.8 - Example 1 90.1 1.5 4B Example 2 90.2 1.6 5B Comparative Example 1 81.2 4 2B Comparative Example 2 93.3 2 3B Comparative Example 3 79 4.6 3B Comparative Example 4 76 6.5 2B Comparative Example 5 59 17.7 0B Comparative Example 6 91.7 1.4 4B Comparative Example 7 97.3 0.6 - Comparative Example 8 95.9 One -

The total content of the conductive material was the same, but referring to the results of Comparative Example 1 in which the second conductive material was not used, optical properties including light transmittance and haze characteristics were lowered compared to the release film according to Example 1, and the initial surface It can be seen that the resistance is also higher than that of Example 1. In addition, it can be seen that the surface resistance after 7 days not only increases significantly compared to the initial surface resistance, but also ^{exceeds 10 10} Ω/m ² , making it difficult to implement stable antistatic properties.

In addition, the total content of the conductive material was the same, but referring to the results of Comparative Example 2 in which the first conductive material was not used, it was determined that the optical properties including light transmittance and haze were similar compared to Example 1. However, the TSI for the one-component coating composition used in Comparative Example 2 is 7, and the dispersion stability of the second conductive material in the one-component coating composition is significantly lower, so that the second conductive material in the release layer is substantially uniform. It was impossible to obtain a well dispersed release layer.

The total content of the conductive material is the same, but referring to the results of Comparative Examples 3 and 4 using MWCNT as the first conductive material or the second conductive material, the surface resistance is 10 ¹⁰ Ω/m ² or less. Although measured, it can be seen that the optical properties are significantly lowered compared to Example 1.

In addition, the content of the second conductive material is the same, but referring to the result of Comparative Example 5 in which the first conductive material was used in excess, the optical properties were measured to be lower than the release films according to Comparative Examples 3 and 4, and It can be seen that the re-adhesion force has been greatly reduced.

On the other hand, referring to the result of Comparative Example 6 in which the content of the first conductive material was the same, but the second conductive material was used significantly less, the change in optical properties compared to the release film according to Example 1 was insignificant, but the surface resistance was 10. ^It can be seen that the antistatic property was deteriorated by exceeding 10 Ω/m ^2. In addition, it can be seen that the surface resistance after 7 days not only increases significantly compared to the initial surface resistance, but also ^{exceeds 10 10} Ω/m ² , making it difficult to implement stable antistatic properties.

As described above, one embodiment of the present invention has been described, but those of ordinary skill in the relevant technical field add, change, delete or add components within the scope not departing from the spirit of the present invention described in the claims. Various modifications and changes can be made to the present invention by means of the like, and this will also be said to be included within the scope of the present invention.

Claims (13)

Base layer; And
A release layer laminated on at least one surface of the base layer;
Including,
The release layer includes a linear first conductive material having an average diameter of 3 to 10 nm and a linear second conductive material having an average diameter of 0.5 to 3 nm,
The first conductive material and the second conductive material are carbon nanotubes having different number of outer walls,
The average diameter of the first conductive material is larger than the average diameter of the second conductive material,
Antistatic release film.
The method of claim 1,
The first conductive material comprises a carbon nanotube having a number of 3 to 9 outer walls,
Antistatic release film.
The method of claim 1,
The second conductive material includes carbon nanotubes having a number of outer walls of less than three,
Antistatic release film.
The method of claim 1,
The release layer is formed by applying a one-component coating composition comprising polysiloxane, a first conductive material and a second conductive material,
Antistatic release film.
The method of claim 4,
At least one of the first conductive material and the second conductive material is silane-coupled to the polysiloxane,
Antistatic release film.
The method of claim 4,
The weight ratio of the first conductive material and the second conductive material in the one-component coating composition is 1.15:1 to 5:1,
Antistatic release film.
The method of claim 4,
In the range of 3 to 60% of solid content, the turbiscan stability index (TSI) for the one-component coating composition is 0.3 or less (based on 7 days),
Antistatic release film.
The method of claim 1,
The light transmittance of the release layer is 85% or more,
Antistatic release film.
The method of claim 1,
The initial surface resistance (Ω1) of the release layer is 10 ¹⁰ Ω/m ² or less,
Antistatic release film.
The method of claim 1,
The ratio (Ω2/Ω1) of the surface resistance (Ω2) after 7 days to the initial surface resistance (Ω1) of the release layer is less than 5,
Antistatic release film.
The method of claim 1,
Haze measured according to ASTM D1003 for the release layer is 2.0% or less,
Antistatic release film.
The method of claim 1,
The adhesion of the first conductive material and the second conductive material to the release layer is 4B or more according to ASTM D3359-97 standard,
Antistatic release film.
The method of claim 1,
For the release layer, Finat test Method No. The residual adhesion rate measured according to 11 is at least 90%,
Antistatic release film.

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