JP2000052495A - Release film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a release film reduced in charging at the time of delivery or running and good in releasability. SOLUTION: A release film is constituted by providing an antistatic layer with a surface intrinsic resistance value of 1×105-1×1012 Ω/(square) on the single surface of a polyester film and providing a release layer on this antistatic layer and a conductive polymer obtained by polymerizing thiophene and/or a thiophene drivative is added to the antistatic layer. The release charge potential at the time of the release of this release film is -5±5 kV.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a release film, and more particularly, to a polyester film as a base film, which is less charged during feeding and running, and is used for a carrier film for molding such as an adhesive film or a resin sheet. The present invention relates to a release film having an excellent peeling behavior without causing a charging failure in a pressure-sensitive adhesive film or a resin sheet formed on a release layer.

[0002]

2. Description of the Related Art A release film is used as a carrier film for forming an adhesive film, a resin sheet, a resin film or a ceramic sheet. For example, a vinyl chloride resin sheet separates a coating liquid comprising a vinyl chloride resin and a solvent. After coating on a shaped film (carrier film), the solvent is removed by heating to form a vinyl chloride sheet (for example, for a marking sheet). These pressure-sensitive adhesive films, resin sheets, resin films, or ceramic sheets are conveyed as they are as a laminated film formed on a carrier film, cut into an appropriate size, and provided for printing or the like.

In the steps of transporting, cutting and printing, the above-mentioned laminated film comes into contact with various rolls and belt conveyors. However, when a release film using a polyester film as a base film is used as a carrier film, the polyester film is easily charged, and when the charging voltage is a certain value or more, when a resin sheet or the like as a product is peeled from the carrier film. In addition, discharge occurs on the surface of the resin sheet or the like, and particularly when the discharge is remarkable, serious physical damage is caused on the surface of the resin sheet or the like.

[0004] Further, the resin sheet or the like is cut into a desired constant shape while being laminated with the carrier film, or after the resin sheet or the like is separated and separated from the carrier film,
When stacking the cut sheets of a certain shape on a case etc., it is not possible to stack them neatly due to electrical repulsion, or conversely, the stacked sheets will stick together due to electrical inquiries, so try to align the corners of the sheets However, when the sheets are picked up one by one, there are problems such as being picked up with several sheets stuck together.

In order to solve these problems, various antistatic treatment methods have been proposed for the release film as follows. As one of the methods, a compound having an antistatic property is directly added to a silicone resin layer. Although a method has been proposed, when a compound having an antistatic property is added, the crosslinking reaction of the silicone resin layer is inhibited, and not only properties such as peeling properties and slipperiness are deteriorated, but also when wound on a roll. Blocking (sticking phenomenon) occurs on the back surface, and in severe cases, it is transferred to a process roll to cause process contamination. Further, when the resin sheet is used for casting, there is a problem that the resin sheet is contaminated by transfer of a silicone resin or an antistatic compound. In these cases, there is a method of reducing the amount of the antistatic compound to be added, but a desired antistatic performance may not be obtained.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to improve the drawbacks of the prior art, to reduce the charge during feeding or running, and to be used for a carrier film for molding such as an adhesive film or a resin sheet. The present invention provides a release film having a release layer surface (having good releasability) which can be peeled off by an appropriate force without causing a charging failure to an adhesive film or a resin sheet formed on the release layer. That is.

[0007]

The object of the present invention is to provide the following:
Or, it is achieved by the surface protective film having the configuration of 2.

That is, in the first configuration, the surface resistivity of the polyester film is 1 × 10 ⁵ to 1 × 10 ^{12 on} one side.
A release film comprising an antistatic layer of Ω / □ and a release layer provided on the antistatic layer, and a conductive film obtained by polymerizing thiophene and / or a thiophene derivative in the antistatic layer. A release film comprising a polymer.

[0009] The second structure is that the one side of the polyester film has a surface resistivity of 1 × 10 ⁵ to 1 × 10 ^5
A release film comprising an antistatic layer of ¹² Ω / □ and a release layer on the other surface, wherein the conductive polymer is obtained by polymerizing thiophene and / or a thiophene derivative in the antistatic layer. And a release film comprising:

In addition to the above two constitutions, a release film in which an antistatic layer is provided on both surfaces of a polyester film and a release layer is provided on one surface, or a release layer is provided on both surfaces.

Hereinafter, the present invention will be described specifically.

The polyester film in the present invention is a film made of polyester.

In the present invention, the polyester is formed from a dicarboxylic acid component and a glycol component. As dicarboxylic acid components, terephthalic acid, isophthalic acid, 2,2
6-naphthalenedicarboxylic acid, hexahydroterephthalic acid, 4,4'-diphenyldicarboxylic acid, adipic acid,
Sebacic acid, dodecanedicarboxylic acid and the like can be exemplified.
In particular, terephthalic acid, 2,
6-Naphthalenedicarboxylic acid is preferred.

As the glycol component, ethylene glycol, diethylene glycol, propylene glycol,
1,3-propanediol, 1,4-butanediol,
Neopentyl glycol, 1,6-hexanediol,
Examples include cyclohexane dimethanol, polyethylene glycol and the like. Particularly, ethylene glycol is preferred from the viewpoint of the rigidity of the film.

The above-mentioned polyester may be a copolyester obtained by copolymerizing the above-mentioned dicarboxylic acid component or glycol component as the third component, or may contain a trifunctional or higher polyvalent carboxylic acid component or a polyol component.
A polyester obtained by copolymerizing a small amount in a range where the obtained polyester is substantially linear (for example, 5 mol% or less) may be used.

As the above polyester, polyethylene terephthalate or polyethylene-2,6-naphthalate is particularly preferred.

Such a polyester can be produced by a conventional method. If the intrinsic viscosity of the polyester (in ortho-chlorophenol, at 35 ° C.) is 0.45 or more, the mechanical properties such as high rigidity of the film are improved. Therefore, it is preferable.

The above polyester includes inorganic fine particles such as silicon oxide, aluminum oxide, magnesium oxide, calcium carbonate, kaolin, talc, titanium oxide, barium sulfate, etc., crosslinked silicone resin, crosslinked polystyrene resin, crosslinked acrylic resin, urea resin. And organic fine particles made of a heat-resistant polymer such as melamine resin. In addition, other resins such as polyethylene, polypropylene, ethylene-propylene copolymer, and olefinic ionomers, stabilizers, antioxidants, ultraviolet absorbers, fluorescent brighteners, and the like can be contained as necessary.

The polyester film of the present invention comprises:
It can be manufactured by a conventionally known method. For example, a biaxially stretched polyester film is produced by drying a polyester, melting it with an extruder, extruding it from a die (eg, T-die, I-die, etc.) onto a rotary cooling drum, and quenching to produce an unstretched film. Then, the unstretched film can be produced by stretching in the machine direction and the transverse direction and, if necessary, by heat setting. The thickness of the polyester film is preferably from 5 μm to 250 μm.

In the present invention, the antistatic layer provided on one side of the polyester film is formed by applying a coating liquid containing a conductive polymer obtained by polymerizing thiophene and / or a thiophene derivative as a component having antistatic properties. Formed by

The conductive polymer used in the present invention is a homopolymer or a copolymer obtained by polymerizing thiophene and / or a thiophene derivative. This conductive polymer is a homopolymer or a copolymer containing as a main unit a unit represented by the following formula (I), formula (II), formula (III) and / or formula (IV). Alternatively, a copolymer containing a small amount of other polymerization units as a copolymer component may be used.

[0022]

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[0023]

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[0024]

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[0025]

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In the above formulas (I) and (II), R ¹ , R ²
Are the same or different, hydrogen element (-H), carbon number 1-20
An aliphatic hydrocarbon group, an alicyclic hydrocarbon group or an aromatic hydrocarbon group, a hydroxyl group (—OH), and a group having a terminal hydroxyl group (—R ³ OH: R ³ is a divalent group having 1 to 20 carbon atoms) A hydrocarbon group (eg, an alkylene group, an arylene group, a cycloalkylene group, an alkylene arylene group, etc.), an alkoxy group (—OR ⁴ : R ⁴ is a hydrocarbon group having 1 to 20 carbon atoms), and an alkoxy group at a terminal. Group (—R ³ OR ⁵ :
R ⁵ is an alkyl group having 1 to 4 carbon atoms, a carboxyl group (—COOH), a carboxyl base (—COOM: M is an alkali metal element, a quaternary amine or tetraphosphonium), and a group having a terminal carboxyl group (— R ³ CO
OH), a group having a terminal carboxyl base (—R ³ CO
OM), an ester group (—COOR ⁵ ), a group having an ester group at the terminal (—R ³ COOR ⁵ ), a sulfonic acid group (—
SO ₃ H), a group having a sulfonic acid group at a terminal (—R ³ S
O ₃ H), a sulfonate group (—SO ₃ M), a group having a terminal sulfonate group (—R ³ SO ₃ M), a sulfonyl group (—SO ₂ R ⁴ ), a group having a terminal sulfonyl group ( —R ³ SO ₂ R ⁴ ), a sulfinyl group (—S (＝ O)
R ⁴ ), a group having a sulfinyl group at the terminal (—R ³ S
(= O) R ⁴ ), an acyl group (—C (＝ O) R ⁶ : R ⁶ is a hydrocarbon group having 1 to 10 carbon atoms), a group having an acyl group at a terminal (—R ³ C (＝ O)) R ⁶ ), an amino group (—N
H ₂ ), a group having an amino group at the terminal (—R ³ NH ₂ ),
A group in which a part or all of a hydrogen element of an amino group is substituted (—NR ⁷ R ⁶ and R ⁷ are a hydrogen element, an alkyl group having 1 to 3 carbon atoms, —CH ₂ OH or —CH ₂ OR ⁶ , R ⁸ Is an alkyl group having 1 to 3 carbon atoms, —CH ₂ OH or —CH ₂
OR ⁶ ), a group having a terminal in which a hydrogen atom of the amino group is partially or wholly substituted (—R ³ NR ⁷ R ⁸ ), a carbamoyl group (—CONH ₂ ), a group having a carbamoyl group at the terminal ( -R ³ CONH ₂ or -R ³ NHCONH
₂ ), a group in which a part or all of a hydrogen element of a carbamoyl group is substituted (—CONR ⁷ R ⁸ ), a group having a group in which a part or all of a hydrogen element of a carbamoyl group is substituted (—R ³ CONR ⁷ R ⁸ ), halogen group (—F, —C
l, —Br, —I), a group in which part of the hydrogen element of R ⁴ has been replaced with a halogen element, — [NR ¹ R ² R ^{9 +} ] [X ⁻ ]
(R ⁹ is a hydrogen element or a hydrocarbon group having 1 to 20 carbon atoms; X ⁻ is F ⁻ , Cl ⁻ , Br ⁻ , I ⁻ , R ^{1)
_{OSO 3 -, R 1 SO 3}} -, NO 3 - or R ¹ COO
^- ), A phosphate group (-P (= O) (O
M) ₂ ), a group having a phosphate group at the terminal (—R ³ P (=
O) (OM) ₂ ), an oxirane group (a group represented by the following formula (V-1)) or a group having an oxirane group at a terminal (a group represented by the following formula (V-2)).

[0027]

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[0028]

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Further, in the above formula (II) and formula (IV) Y ^-
Is an element or compound having an anion (Cl ⁻ , Br
^{-, I -, F -,} R 1 OSO 3 -, R 1 SO 3 -, NO
₃ ^-, R ¹ COO ^- shows the like) or a polymer having these anions.

The polymerized units represented by the formulas (I), (II), (III) and / or (IV) include, for example,
The following formulas (I-1) to (I-12), and the following formula (II-1)
To formula (II-2), the following formula (III-1) and the following formula (IV
-1) to Formula (IV-2).

[0031]

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[0032]

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[0033]

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[0034]

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[0035]

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[0036]

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[0037]

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[0038]

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[0039]

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[0040]

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[0041]

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[0042]

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[0043]

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[0044]

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[0045]

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[0046]

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[0047]

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The conductive polymer obtained by polymerizing thiophene and / or a thiophene derivative may be doped with a doping agent, for example, with respect to 100 parts by weight of the conductive polymer in order to further improve the antistatic property. 0.1 to 500 parts by weight. As the doping agent, LiC
1, R ¹⁰ COOLi (R ¹⁰ : a saturated hydrocarbon group having 1 to 30 carbon atoms), R ¹⁰ SO ₃ Li, R ¹⁰ COONa, R ¹⁰ SO
^{_{3 Na, R 10 COOK, R}} 10 SO 3 K, _{tetraethylammonium, I 2, BF 3 Na,} BF 4 Na, HClO
₄ , CF ₃ SO ₃ H, FeCl ₃ , tetracyanoquinoline (TCNQ), Na ₂ B ₁₀ Cl ₁₀ , phthalocyanine,
Porphyrin, glutamic acid, alkyl sulfonate,
Polystyrene sulfonic acid Na (K, Li) salt, styrene / styrene sulfonic acid Na (K, Li) salt copolymer, polystyrene sulfonic acid anion (for example, the above-mentioned formula (II-
2a), a polymer represented by the formula (IV-1a)), a styrenesulfonic acid / styrenesulfonic acid anion copolymer (for example, a copolymer represented by the formula (II-1a) or the formula (IV-2a)) ) And the like.

In the present invention, a binder resin can be blended with the conductive polymer in order to improve the adhesion between the polyester film and the antistatic layer.
The binder resin is preferably a resin having at least one secondary transition point of 20 to 150 ° C. selected from the group consisting of a polyester resin, an acrylic resin, an acryl-modified polyester resin, and a urethane resin. If the secondary transition point is less than 20 ° C., the blocking resistance of the antistatic coating film will be poor, and if it exceeds 150 ° C., the abrasion resistance of the antistatic layer will be insufficient.

The polyester resin has a secondary transition point of 20 to 1 comprising a dicarboxylic acid component and a glycol component.
50 ° C copolyesters are preferred. As the dicarboxylic acid component, for example, terephthalic acid, isophthalic acid,
2,6-naphthalenedicarboxylic acid, hexahydroterephthalic acid, 4,4'-diphenyldicarboxylic acid, adipic acid, sebacic acid, dodecanedicarboxylic acid, 5-Na sulfoisophthalic acid, 5-K sulfoisophthalic acid, and the like. it can. Examples of the glycol component include, for example, ethylene glycol, diethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, cyclohexanedimethanol, polyethylene glycol, and bisphenol A / alkylene oxide adducts. .

The copolymerized polyester having a secondary transition point of 20 to 150 ° C. uses an aromatic dicarboxylic acid as a main component as a dicarboxylic acid component and selects a glycol component such that the secondary transition point falls within the above range. Can be obtained.

The polyester resin can be produced by a conventional method. Average molecular weight of 10,000 to 50,000
0 means that the antistatic layer has good abrasion resistance,
This is preferable because the antistatic layer has good blocking resistance.

The acrylic resin has a secondary transition point of from 20 to 15 obtained by polymerizing an acrylate monomer.
Acrylic copolymers at 0 ° C. are preferred. Examples of the acrylate monomer include methyl methacrylate, ethyl methacrylate, butyl methacrylate, methyl acrylate, ethyl acrylate, butyl acrylate, ethyl crotonate, glycidyl methacrylate, 2-hydroxyethyl acrylate And 2-ethylhexyl acrylate.

The acrylic copolymer is obtained by mixing at least one of the above-mentioned acrylate monomers with acrylamide, methacrylamide, acrylic acid, methacrylic acid, sodium acrylate, potassium methacrylate, ammonium acrylate, It may be a copolymer obtained by polymerizing an acrylic acid monomer such as methylolacrylamide or N-methoxymethylacrylamide.

In addition to the acrylic copolymer, monomers such as vinyl chloride, vinyl acetate, styrene, vinyl ether, butadiene, isoprene, and sodium vinyl sulfonate can be used as copolymer components.

The acrylic copolymer includes an acrylate component, a methacrylate component, an acrylic acid component, an acrylamide component, a 2-hydroxyethyl acrylate component,
It is preferable that a hydrophilic component such as an N-methylol acrylamide component be combined as a copolymer component because the dispersibility and the solubility in the aqueous coating solution are improved. Further, a copolymer having a functional group in a molecular side chain may be used.

The acrylic copolymer having a secondary transition point of 20 to 150 ° C. uses a hard component such as methyl methacrylate or ethyl methacrylate as a main component and uses an acrylic copolymer such as an acrylate as a copolymer component. It can be obtained by copolymerizing the soft component at such a ratio that the secondary transition point falls within the above range. Further, the secondary transition point of the acrylic copolymer can be adjusted by using a component having a methylol group, a methoxymethyl group, or the like as a copolymer component and crosslinking these groups.

The average molecular weight of the acrylic copolymer is 10,
The range of 000 to 500,000 is preferable because the antistatic layer has good abrasion resistance and the antistatic layer has good blocking resistance.

The acrylic modified polyester resin is a modified polyester resin having a secondary transition point of from 20 to 150 ° C. obtained by polymerizing the acrylate monomer and / or the acrylate monomer on the polyester resin. It is a polymer. For example, it can be obtained by graft-polymerizing the acrylate monomer and / or the acrylate monomer to a polyester resin in an aqueous liquid using a radical initiator. This modified copolymer may have a functional group in a molecular side chain. Further, the modified copolymer preferably has an average molecular weight of 10,000 to 500,000 because the antistatic layer has good abrasion resistance and the antistatic layer has good blocking resistance.

The acrylic-modified polyester resin having a secondary transition point of 20 to 150 ° C. has a secondary transition point of 20 to 150 ° C.
With respect to the copolymerized polyester at ℃, a hard component such as methyl methacrylate or ethyl methacrylate, and a soft component such as an acrylate at a ratio at which the secondary transition point of the acrylic-modified polyester resin is 20 to 150 ° C. It can be obtained by copolymerization.

As the urethane resin, a polyurethane polymer having a secondary transition point of 20 to 150 ° C. made of fatty acid polyether, aliphatic polyester, diisocyanate, diamine, glycol, dimethylolpropionate or the like is preferable. The average molecular weight of the polyurethane polymer is preferably from 5,000 to 50,000 from the viewpoint of abrasion resistance, because the abrasion resistance of the antistatic layer becomes good and the antistatic property of the antistatic layer becomes good.

The polyurethane resin having a secondary transition point of 20 to 150 ° C. can be obtained by using a prepolymer containing an aromatic polyether or polyester, an aromatic diisocyanate, an alkylenediamine, an alkyl glycol, and a dimethylolpropionate. Can be.

As the binder resin used in the present invention, one resin selected from the above polyester resins, acrylic resins, acryl-modified polyester resins and polyurethane resins can be used alone, or two or more resins can be mixed. It can also be used.

The antistatic layer in the first and second constitutions of the present invention is formed by applying an aqueous coating solution containing a conductive polymer obtained by polymerizing thiophene and / or a thiophene derivative, followed by drying and curing. 1 × 10
It is a coating film of ⁵ to 1 × 10 ¹² Ω / □. If the surface resistivity is less than 1 × 10 ⁵ Ω / □, the coating becomes brittle, and
If it exceeds × 10 ¹² Ω / □, the antistatic property will be insufficient.

In the first and second constitutions of the present invention, the antistatic layer comprises 1 to 95% by weight (particularly 5 to 70% by weight) of a conductive polymer and 5 to 99% by weight (particularly 30 to 95% by weight). (% By weight) of an aqueous coating solution containing the composition comprising the above binder resin, followed by drying and curing.

When the ratio of the conductive polymer to the binder resin is in the above range, the adhesion between the polyester film and the antistatic layer becomes good, and the antistatic property of the antistatic layer is improved.
It is preferable because the adhesiveness and the abrasion resistance are improved.

The composition of the conductive polymer and the binder resin can be obtained by, for example, a method of mixing the conductive polymer and the binder resin, and the surface of the fine particle binder resin is coated with the conductive polymer. And a method of chemically bonding a functional group fitted to the conductive polymer to a functional group fitted to the binder resin.

The components of the antistatic layer include, in addition to the above components, epoxy resins, vinyl resins, polyether resins, and water-soluble resins for the purpose of adjusting the adhesion, solvent resistance, and water resistance of the antistatic layer. A small amount of cellulose-based resin).

As a component of the antistatic layer, inorganic or organic fine particles having an average particle size of about 0.01 to 20 μm are used as a lubricant in order to improve the slipperiness and blocking resistance of the coating film. For example, it can be contained at a mixing ratio of 0.001 to 5% by weight. Specific examples of such fine particles include silica, alumina, titanium oxide, carbon black, kaolin, inorganic fine particles such as calcium carbonate, polystyrene resin, cross-linked polystyrene resin, acrylic resin, cross-linked acrylic resin, melamine resin particles, silicone resin,
Organic fine particles such as a fluorine resin, a urea resin, and a benzoguanamine resin are preferably exemplified. The organic fine particles may be a thermoplastic resin or a thermosetting resin as long as the resin can maintain the state of the fine particles in the coating film, and may be cross-linked at a degree of cross-linking according to the purpose. It may be a resin.

In addition to the fine particles, surfactants, antioxidants, colorants, pigments, fluorescent brighteners, plasticizers, crosslinking agents, organic lubricants (sliding agents), ultraviolet absorbers, other antistatic agents and the like can be used. It can be added as needed.

In the present invention, the antistatic layer is formed using an aqueous coating solution containing the above composition. The solid content of the aqueous coating solution is preferably from 1 to 30% by weight, more preferably from 2 to 20% by weight. Is preferred. When the solid content concentration is within this range, the viscosity of the aqueous coating liquid becomes suitable for coating. The aqueous coating liquid used in the present invention can be used in any form such as an aqueous solution, an aqueous dispersion, and an emulsion. Further, the aqueous coating liquid may contain a small amount of a solvent.

In the present invention, the antistatic layer is preferably formed by applying the above-mentioned coating solution on one surface of a polyester film. A film or a polyester film before completion of the crystal orientation is preferable.

Examples of the polyester film in which the crystal orientation has been completed include a film obtained by biaxially stretching an unstretched film in a longitudinal direction and a transverse direction by heat-melting the polyester and then heat-setting. As a polyester film before the crystal orientation is completed, an unstretched film in which the polyester is hot-melted and directly formed into a film, a uniaxially stretched film in which the unstretched film is oriented in either the longitudinal direction or the transverse direction, An example is a film stretched and oriented at a low magnification in two directions, that is, a longitudinal direction and a lateral direction (a biaxially stretched film before being finally stretched again in a longitudinal direction and a lateral direction to complete oriented crystallization).

As a method of applying the coating liquid to the polyester film, a known coating method can be applied. For example, a roll coating method, a gravure code method, a microgravure code method, a reverse coat method, a roll brush method, a spray coat method, an air knife coat method, an impregnation method, a curtain coat method, or the like may be applied alone or in combination.

In the present invention, the thickness of the antistatic layer is
It is preferably from 0.01 to 1 μm, more preferably from 0.02 to 0.5 μm. If the thickness is less than 0.01 μm, a sufficient antistatic effect may not be obtained, while if it exceeds 1 μm, the blocking resistance may decrease.

In the first and second constitutions of the present invention, the release layer provided on one side of the polyester film is formed by applying a coating liquid exhibiting various releasability and drying or curing.

As a component that exhibits such release, a curable silicone resin is preferable. Any of the curing type silicone resins such as condensation reaction type, addition reaction type, and ultraviolet or electron beam curing type can be used. One of these curable silicone resins may be used alone, or two or more thereof may be used in combination.

The curing reaction of various silicone resins can be shown as follows.

[0079]

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Examples of the condensation reaction type silicone resin include a polydimethylsiloxane having a terminal —OH group and a polydimethylsiloxane (hydrogensilane) having a terminal —H group as an organotin catalyst (eg, an organotin acylate catalyst). To form a three-dimensional cross-linked structure.

As an addition reaction type silicone resin, for example, polydimethylsiloxane having a vinyl group introduced into a terminal and hydrogen silane are reacted using a platinum catalyst.
One that forms a three-dimensional crosslinked structure may be mentioned.

As the ultraviolet-curable silicone resin,
For example, the most basic type uses the same radical reaction as ordinary silicone rubber crosslinking, the one that introduces an acrylic group and cures it, and the one that decomposes an onium salt with ultraviolet rays to generate a strong acid, thereby forming an epoxy ring. Examples thereof include those that are cleaved and crosslinked, and those that are crosslinked by the addition reaction of thiol to vinylsiloxane. Electron beams have higher energy than ultraviolet rays, and a radical crosslinking reaction occurs without using an initiator as in the case of ultraviolet curing.

The curable silicone resin preferably has a polymerization degree of about 500,000 to 200,000, preferably about 1,000 to 100,000. Specific examples thereof include KS-718 manufactured by Shin-Etsu Chemical Co., Ltd. -774, -775, -77
8, -779H, -830, -835, -837, -8
38, -839, -841, -843, -847, -8
47H, X-62-2418, -2422, -212
5, -2492, -2494, -470, -2366,
-630, X-92-140, -128, KS-723
A / B, -705F, -708A, -883, -70
9, -719, TPR-67 manufactured by Toshiba Silicone Co., Ltd.
01, -6702, -6703, -3704, -670
5, -6722, -6721, -6700, XSR-7
029, YSR-3022, YR-3286, DK-Q3-202, -203, -2 manufactured by Dow Corning Co., Ltd.
04, -210, -240, -3003, -205,-
3057, SFXF-2560, SD-7226, -7320, manufactured by Dow Corning Toray Silicone Co., Ltd.
-7229, BY24-900, -171, -312,
-374, SRX-375, SYL-0FF23, SR
Examples include X-244, SEX-290, and SILCOLASE 425 manufactured by ICI Japan Ltd. Also, JP-A-47-34447,
The silicone resin described in JP-B-52-40918 can also be used.

As a coating method for forming the curable silicone resin coating film on the film surface, a conventionally known method such as a bar coating method, a doctor blade method, a reverse roll coating method or a gravure roll coating method is used. it can.

The drying and curing (thermal curing, ultraviolet curing, etc.) of the coating film can be performed individually or simultaneously.
When performing simultaneously, it is preferable to perform at 100 degreeC or more. Drying and curing conditions are 100 ° C or higher and 30
Seconds or more are preferred. If the drying temperature is less than 100 ° C. and the curing time is less than 30 seconds, the curing of the coating film is incomplete and the coating film is apt to fall off, which is not preferable.

The thickness of the curable silicone resin coating is not particularly limited, but is preferably in the range of 0.05 to 0.5 μm. If the thickness of the coating film is less than this range, the releasing performance is reduced and satisfactory performance cannot be obtained. Conversely, if the thickness of the coating film is larger than this range, it takes a long time for curing, which causes a disadvantage in production.

In addition, applications that dislike curable silicone release agents,
For example, a polymer having a long alkyl side chain is preferable for use as a casting support film for sheeting a water-based pressure-sensitive adhesive or resin solution that is easy to repel or for applications where the migration of silicone components must not be small,
A copolymer of acrylic acid and an alkyl acrylate having an alkyl chain having 12 or more carbon atoms, particularly 16 to 20 carbon atoms, is more preferred. When the number of carbon atoms in the alkyl chain of the alkyl acrylate is less than 12, sufficient releasability may not be obtained.

Of these, particularly preferred are copolymers obtained by long-chain alkylation of polyvinyl alcohol or polyethyleneimine with chlorinated alkylol or alkyl isocyanate. Specifically, a copolymer obtained by reacting polyvinyl alcohol with octadecyl isocyanate is preferred. Polyvinyl-N-octadecyl carbamate,
Examples include polyethyleneimine-N-octadecylcarbamate obtained by the reaction of polyethyleneimine with octadecyl isocyanate.

In the present invention, a fluorine-based release agent or a wax-based release agent such as paraffin wax or carnauba wax can be used as long as there is no problem.

The release layer using the polymer having a long alkyl side chain has a binder for improving the strength of the layer, adhesion to the antistatic upper layer or the polyester film, water resistance, solvent resistance, blocking property and the like. In addition, it may contain a thermoplastic compound such as a thermoplastic polyester resin, an acrylic resin, and a polyvinyl resin and / or a polymer compound such as a thermosetting resin such as a thermosetting acrylic resin, a urethane resin, a melamine resin, and an epoxy resin. Preferably
It is particularly preferable that the crosslinking agent contains at least one selected from methylolated or alkylolated melamine-based, urea-based, glyoxal-based, acrylamide-based compounds, epoxy compounds, and polyisocyanates.

The release layer can be coated in the same manner as the coating method of the antistatic layer, such as the concentration of the coating solution, the coating method and the coating conditions.

In the first and second constitutions of the present invention, the thickness of the release layer is 0.01 to 1 μm, more preferably 0.03 to 0.5 μm.
It is preferably μm. If the thickness is less than 0.01 μm, sufficient release effect may not be obtained, while 1 μm
Layers above m are over-quality and uneconomical.

In addition to the first and second constitutions of the present invention, an antistatic layer may be provided on both surfaces of the polyester film, and the object of the present invention can be sufficiently achieved, but the quality is excessive and uneconomical. .

The release film of the present invention preferably has a peeling withstand voltage of -5 to +5 KV when released.

[0095]

The present invention will be further described below with reference to examples. In addition, each characteristic value was measured by the following method.

(1) Peel strength A polyester adhesive tape (nit-31B) was adhered to the release layer surface of the film, pressed with a 5 kg pressure roller and maintained at 70 ° C. for 20 hours. The peel force (R _fO ) from the tape was measured with a tensile tester.

(2) Residual Adhesion Rate The polyester adhesive tape (Nit-31B) was JIS
Cold rolled stainless steel sheet (SUS3
04) was measured for the peeling force after application, and the result was taken as the basic adhesive force (f _O ). Next, the new polyester pressure-sensitive adhesive tape was pressed against the release layer surface of the sample film with a 5 kg pressure roller and maintained for 30 seconds, and then the pressure-sensitive adhesive tape was peeled off.
Then, the peeled polyester pressure-sensitive adhesive tape was stuck on the stainless steel plate, and the peeling force of the bonded portion was measured to obtain a residual adhesive force (f). From the obtained basic adhesive strength (f _O ) and residual adhesive strength (f), a residual adhesive rate was determined using the following equation.

Residual adhesion rate (%) = (f / f _O ) × 100 (3) Chargeability (peeling charge evaluation method) A polyester pressure-sensitive adhesive tape (nit-31B) is adhered to the release layer surface of the film, and 5 kg is pressed. After being pressed with a roller and maintained at 70 ° C. for 20 hours, the release film side was fixed downward, and the polyester pressure-sensitive adhesive tape was
Peeling was performed at a speed of mm / min, and the potential of the pressure-sensitive adhesive surface of the peeled polyester pressure-sensitive adhesive tape was measured from a distance of 3 cm from the pressure-sensitive adhesive surface, and was determined as a peeling charge potential.

(4) Surface Specific Resistance Using a unique low resistance measuring device manufactured by Takeda Riken Co., Ltd.
The surface specific resistance value was measured after 1 minute at an applied voltage of 500 V under the conditions of ° C and a measurement humidity of 65% RH and 45% RH. The surface resistivity is preferably less than 1 × 10 ¹³ Ω.

[Example 1] Polyethylene terephthalate having an intrinsic viscosity of 0.64 was melted and cast on a cooling drum to obtain an unstretched film.
And stretched 3.5 times in the machine direction to obtain a uniaxially stretched film. Next, on one surface of the uniaxially stretched film, 15 parts by weight of a copolymer (average molecular weight: 12,600) having the above formula (IV-2) as a repeating unit was added to a copolymer having the above formula (IV-2a) as a repeating unit. Combination (a in the formula (IV-2a) is 4
0 mol%, b is 60 mol% copolymer, average molecular weight: 3
8,700), and 30 parts by weight of a conductive polymer doped with 25 parts by weight of terephthalic acid 54 as a dicarboxylic acid component.
Mol%, isophthalic acid 37 mol%, adipic acid 5 mol%
And a copolymer polyester obtained using 4 mol% of 5-Na sulfoisophthalic acid, 92 mol% of ethylene glycol, 5 mol% of diethylene glycol, and 3 mol% of 1,4-butanediol as glycol components (Tg 59 ° C.,
An aqueous coating solution of 5% by weight of a composition comprising 70 parts by weight of an average molecular weight (20,660) and 10 parts by weight of a nonionic surfactant (polyoxyethylene nonylphenyl ether) was applied by a gravure coater. Then, after drying at 104 ° C,
The film is stretched 3.9 times in the transverse direction at 108 ° C. and further heat-treated at 220 ° C. to a total thickness of 38 μm and a thickness of the antistatic layer of 0.12 μm.
m of laminated film was prepared.

Next, an addition-reaction silicone resin (manufactured by Shin-Etsu Chemical Co., Ltd .; KS-
778, 100% by weight of a 30% solids solution in toluene) and a platinum catalyst (PL-50T, manufactured by Shin-Etsu Chemical Co., Ltd.)
1 part by weight was dissolved in toluene to prepare a toluene solution having a total solid content of 3% by weight (for releasing layer coating), and then applied using a gravure coater, and applied at 150 ° C. for 30 minutes. The film was dried and cured, and a release layer having a thickness of 0.2 μm was provided to form a release film. Table 1 shows the characteristics of the release film.

Example 2 As a release layer, polyvinyl-
N-Ocdecyl isocyanate (manufactured by Asio Sangyo Co., Ltd.
Asionyl RA-585S) is dissolved in toluene,
A release film was prepared in the same manner as in Example 1 except that a toluene solution having a solid content of 2% by weight was used. Table 1 shows the characteristics of the release film.

Example 3 A release film was prepared in the same manner as in Example 1 except that a release layer was provided on the surface opposite to the antistatic layer.

Example 4 Instead of a uniaxially stretched film, a biaxially stretched polyester film (Tetron film manufactured by Teijin Limited, G ₂ -38 μm) was coated on one side with the same aqueous paint as in Example 1 using a gravure coater. And apply 150
Drying and curing for 1 minute at 0 ° C, thickness of antistatic layer 0.12
A μm laminated film was prepared, and a release layer was laminated under the same method and conditions as in Example 1 to prepare a release film.
Table 1 shows the characteristics of the release film.

Comparative Example 1 A release film was prepared in the same manner as in Example 1 except that the antistatic layer was not provided. Table 1 shows the characteristics of the release film.

[0106]

[Table 1]

[0107]

According to the present invention, an adhesive film formed on a release layer when used for a carrier film for molding, such as an adhesive film or a resin sheet, is less charged during feeding or running. It is possible to provide a release film capable of peeling an adhesive film, a resin sheet, or the like with an appropriate force without causing a charging failure in the resin sheet or the like.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08G 63/189 C08G 63/189 C09D 175/00 C09D 175/00 183/04 183/04 F-term (Reference) 4F100 AA07B AH06 AK04C AK21C AK41A AK42A AK52C AL01C AR00B AR00C BA03 BA07 BA10B BA10C GB41 JG03 JG03B JG04B JK07 JL14 JL14C YY00B 4J029 AA03 AB07 AC01 AC02 BA03 BA03 BA03 BA08 BA03 BA03 DB14 HA01 HB01 JE182 JE193 JF032 4J032 BA03 BA04 BA05 BB01 BB03 BB04 BB08 CF02 CG01 CG08 4J038 CE022 CR072 DK001 DL032 NA10 NA20 PA07 PC08

Claims (6)

[Claims] 1. A releasing method comprising: providing an antistatic layer having a surface resistivity of 1 × 10 ⁵ to 1 × 10 ¹² Ω / □ on one surface of a polyester film, and providing a release layer on the antistatic layer. A release film, comprising a conductive polymer obtained by polymerizing thiophene and / or a thiophene derivative in an antistatic layer. 2. A release film comprising an antistatic layer having a surface resistivity of 1 × 10 ⁵ to 1 × 10 ¹² Ω / □ on one surface of a polyester film and a release layer on the other surface. A release film, wherein the antistatic layer contains a conductive polymer obtained by polymerizing thiophene and / or a thiophene derivative. 3. The release film according to claim 1, wherein the release charge potential when the release film is released is -5 to +5 kV. 4. The release film according to claim 1, wherein the component exhibiting releasability is a curable silicone resin. 5. The component according to claim 1, wherein the component exhibiting releasability is a copolymer obtained by long-chain alkylation of polyvinyl alcohol or polyethyleneimine with chlorinated alkylol or alkyl isocyanate. 4. The release film according to item 1. 6. The release film according to claim 1, wherein the polyester film is a polyethylene terephthalate film or a polyethylene-2,6-naphthalate film.