CN116406328A

CN116406328A - Release film

Info

Publication number: CN116406328A
Application number: CN202180073874.8A
Authority: CN
Inventors: 柄泽泰纪; 村岛峻介
Original assignee: Lintec Corp
Current assignee: Lintec Corp
Priority date: 2020-11-04
Filing date: 2021-09-22
Publication date: 2023-07-07
Also published as: JPWO2022097384A1; TW202229011A; WO2022097384A1; KR20230098786A

Abstract

The present invention provides a release film comprising a base material and a release agent layer provided on at least one surface side of the base material, wherein the release agent layer is formed from a release agent composition containing an active energy ray-curable component and a mercapto group-containing polyorganosiloxane. The release film exhibits excellent releasability.

Description

Release film

Technical Field

The present invention relates to a release film, and more particularly, to a release film and the like that can be used for manufacturing a ceramic green sheet.

Background

Conventionally, in the production of laminated ceramic products such as laminated ceramic capacitors and multilayer ceramic substrates, ceramic green sheets have been molded, and a plurality of obtained ceramic green sheets have been laminated and fired.

The ceramic green sheet is formed to a uniform thickness by applying a ceramic slurry containing a ceramic material such as barium titanate or titanium oxide to a release film. As the release film, a release film in which a film base is subjected to a release treatment with a silicone compound such as polysiloxane to form a release agent layer is generally used.

In recent years, along with miniaturization and higher performance of electronic devices, miniaturization and multilayering of laminated ceramic capacitors and multilayer ceramic substrates have been advanced, and thinning of ceramic green sheets has also been advanced. However, if the ceramic green sheet is thinned so that the thickness of the ceramic green sheet after drying is, for example, 3 μm or less, defects such as pinholes (pin holes) and thickness unevenness tend to occur in the ceramic green sheet when the ceramic slurry is applied and dried due to the surface state of the release agent layer in the release film. In addition, when the molded ceramic green sheet is peeled from the release film, defects such as breakage due to a decrease in strength of the ceramic green sheet are likely to occur.

Therefore, the release film is required to have releasability capable of releasing the thin film ceramic green sheet molded on the release film from the release film without causing breakage or the like.

From the viewpoint of achieving the releasability described above, patent document 1 discloses a release film comprising, on one surface of a substrate, a release agent layer formed using a release agent layer forming material containing an active energy ray-curable compound (a 1) and a polyorganosiloxane (b 1), and, on the other surface of the substrate, a back surface coating layer formed using a back surface coating layer forming material containing an active energy ray-curable compound (a 2).

Prior art literature

Patent literature

Patent document 1: japanese patent No. 5451951

Disclosure of Invention

Technical problem to be solved by the invention

However, the conventional release film may not necessarily achieve the desired releasability. Therefore, a release film having more excellent releasability is demanded.

The present invention has been made in view of the above-described circumstances, and an object of the present invention is to provide a release film exhibiting excellent releasability.

Technical means for solving the technical problems

In order to achieve the above object, first, the present invention provides a release film comprising a base material and a release agent layer provided on at least one surface side of the base material, wherein the release agent layer is formed from a release agent composition containing an active energy ray-curable component and a mercapto group-containing polyorganosiloxane (invention 1).

The release sheet of the invention (invention 1) can exhibit excellent releasability by forming the release agent layer from the release agent composition.

In the above invention (invention 1), it is preferable that the mercapto group of the mercapto group-containing polyorganosiloxane is present in the side chain (invention 2).

In the above inventions (inventions 1 and 2), the mercapto group-containing polyorganosiloxane preferably has a functional group equivalent of 10g/mol or more and 50,000g/mol or less (invention 3).

In the above inventions (inventions 1 to 3), the release agent composition preferably contains a crosslinking agent (invention 4).

In the above invention (invention 4), the crosslinking agent is preferably an isocyanate-based crosslinking agent (invention 5).

In the above inventions (inventions 1 to 5), the active energy ray-curable component is preferably a polyfunctional (meth) acrylate (invention 6).

In the above invention (invention 6), the number of functional groups of the polyfunctional (meth) acrylate is preferably 3 to 6 (invention 7).

In the above inventions (inventions 1 to 7), the release film is preferably used in the ceramic green sheet production step (invention 8).

Effects of the invention

The release film of the present invention can exhibit excellent releasability.

Detailed Description

Hereinafter, embodiments of the present invention will be described.

The release film according to one embodiment of the present invention is configured to include a base material and a release agent layer provided on at least one surface side of the base material.

With the release film of the present embodiment, the release agent layer is formed of a release agent composition containing an active energy ray-curable component and a mercapto group-containing polyorganosiloxane.

In the above-mentioned release agent composition, since a polyorganosiloxane having a mercapto group is used as the polyorganosiloxane, the component derived from the polyorganosiloxane is easily biased to be distributed on the surface of the cured coating film. The reason for this is presumed not to exclude other reasons, namely that the reactivity between the mercapto groups and the active energy ray-curable component or the crosslinking agent is high, and therefore the polyorganosiloxane unevenly distributed in the coating film before curing undergoes a reaction of the mercapto groups before diffusing and is fixed in a state of being more biased to be distributed on the release surface (the surface of the release agent layer opposite to the substrate). As a result, the surface free energy of the release surface is moderately reduced, and the release agent layer has moderate hardness and exhibits excellent releasability.

1. Substrate material

The substrate in the release film of the present embodiment is not particularly limited, and any substrate may be appropriately selected from conventionally known substrates and used. Examples of the substrate include polyesters such as polyethylene terephthalate and polyethylene naphthalate, polyolefins such as polypropylene and polymethylpentene, and plastic films such as polycarbonate and polyvinyl acetate. These plastic films may be single-layered or multi-layered of 2 or more layers of the same kind or different kinds. Among them, a polyester film is preferable, and a polyethylene terephthalate film is particularly preferable. Since the polyethylene terephthalate film is less likely to generate dust or the like at the time of processing and use, for example, coating failure or the like due to dust or the like can be effectively prevented.

In addition, in the base material, for the purpose of improving adhesion with the release agent layer provided on the surface thereof, one or both surfaces may be subjected to surface treatment by an oxidation method, a concavity and convexity method, or the like, or plasma treatment, as necessary. Examples of the oxidation method include corona discharge treatment, plasma discharge treatment, chromium oxidation treatment (wet type), flame treatment, hot air treatment, ozone, ultraviolet irradiation treatment, and the like, and examples of the relief method include sandblasting treatment and thermal spraying treatment. These surface treatments may be appropriately selected according to the kind of the substrate, but in view of the effect and the operability, a corona discharge treatment is preferably used.

The thickness of the substrate is preferably 10 μm or more, particularly preferably 15 μm or more, and further preferably 20 μm or more. The thickness is preferably 300 μm or less, particularly preferably 200 μm or less, and further preferably 125 μm or less.

2. Stripper layer

2-1 each component

The release agent layer of the present embodiment is formed of a release agent composition containing an active energy ray-curable component and a mercapto group-containing polyorganosiloxane, and optionally containing a crosslinking agent, a photopolymerization initiator, or a curing accelerator.

(1) Active energy ray-curable component

The active energy ray-curable component is not particularly limited as long as it is a component cured by irradiation with active energy rays, and may be any of a monomer, an oligomer, and a polymer, or may be a mixture of these components. In particular, as the active energy ray-curable component, a component constituting an acrylic resin is preferably used, and a polyfunctional (meth) acrylate is particularly preferably used. In the present specification, "meth) acrylate" means both acrylate and methacrylate.

Examples of the polyfunctional (meth) acrylate include 2-functional type such as 1, 4-butanediol di (meth) acrylate, 1, 6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, neopentyl glycol adipate di (meth) acrylate, hydroxypivalate neopentyl glycol di (meth) acrylate, dicyclopentanyl di (meth) acrylate, caprolactone-modified dicyclopentanyl (meth) acrylate, ethylene oxide-modified phosphoric acid di (meth) acrylate, isocyanuric acid di (acryloyloxyethyl) ester, and allylated dicyclohexyl di (meth) acrylate; 3-functionality such as trimethylolpropane tri (meth) acrylate, dipentaerythritol tri (meth) acrylate, propionic acid-modified dipentaerythritol tri (meth) acrylate, pentaerythritol tri (meth) acrylate, propylene oxide-modified trimethylolpropane tri (meth) acrylate, tris (acryloyloxyethyl) isocyanurate, epsilon-caprolactone-modified tris (2- (meth) acryloyloxyethyl) isocyanurate; 4-functionality such as diglycerol tetra (meth) acrylate and pentaerythritol tetra (meth) acrylate; dipentaerythritol penta (meth) acrylate, propionic acid-modified dipentaerythritol penta (meth) acrylate, and the like; dipentaerythritol hexa (meth) acrylate, caprolactone-modified dipentaerythritol hexa (meth) acrylate, and the like. These polyfunctional (meth) acrylates may be used alone or in combination of 1 or more than 2. The polyfunctional (meth) acrylate is preferably 3 to 6 functional groups, particularly preferably 5 to 6 functional groups, from the viewpoint that the release agent layer has a suitable hardness and exhibits more excellent releasability. Among the polyfunctional (meth) acrylates, at least one of pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate is preferably used.

The active energy ray-curable component preferably has a reactive group that can react with a crosslinking agent described later. Examples of the reactive group include a hydroxyl group, a carboxyl group, an amino group, and the like, and among these, a hydroxyl group is preferable. The active energy ray-curable component has a reactive group that can react with a crosslinking agent described later, and thus the active energy ray-curable component and the crosslinking agent can be bonded via these groups, so that a three-dimensional structure described later can be effectively formed.

When the active energy ray-curable component has a hydroxyl group, the hydroxyl value is preferably 1.0mgKOH/g or more, and particularly preferably 3.0mgKOH/g or more. The hydroxyl value is preferably 500mgKOH/g or less, and particularly preferably 300mgKOH/g or less. By setting the hydroxyl value in the above range, a three-dimensional structure described later can be formed more effectively.

The blend amount of the active energy ray-curable component in the release agent composition is preferably 50 mass% or more, particularly preferably 55 mass% or more, and further preferably 60 mass% or more, with respect to the release film of the present embodiment. The blending amount of the active energy ray-curable component in the stripper composition is preferably 90 mass% or less, particularly preferably 85 mass% or less, and further preferably 80 mass% or less. In the release film of the present embodiment, the release agent layer has a more moderate hardness and the release property is more excellent by making the blending amount of the active energy ray-curable component within the above range.

(2) Mercapto group-containing polyorganosiloxanes

The mercapto group-containing polyorganosiloxane is not particularly limited as long as it has a mercapto group and a release agent layer can be formed using the release agent composition, and for example, a polyorganosiloxane represented by the following general formula (1) can be used.

[ chemical formula 1]

In the formula (1), m is an integer of 1 or more. In addition, R ¹ ～R ⁸ At least one of them is an organic group having a mercapto group. R is R ¹ ～R ⁸ The remaining groups (groups having no mercapto group) in (a) are preferably hydrogen atoms, alkyl groups or organic groups. In addition, R ¹ ～R ⁸ May be the same or different. In addition, there are a plurality of R ¹ R is R ² When R is ¹ R is R ² May be the same as or different from each other.

Examples of the mercapto group-containing polyorganosiloxane include a polyorganosiloxane in which a mercapto group is introduced into a side chain of the organopolysiloxane (in the side chain formula (1), R ¹ R is R ² At least one of them is an organic group having a mercapto group), a polyorganosiloxane having mercapto groups introduced at both terminals of the organopolysiloxane (both terminal type: in the formula (1), R ³ ～R ⁵ At least one of R ⁶ ～R ⁸ At least one of which is an organic group having a mercapto group, and introducing a mercapto group to either of both terminals of the organopolysiloxanePolyorganosiloxane (one terminal: in the formula (1), R ³ ～R ⁵ At least one of or R ⁶ ～R ⁸ At least one of them is an organic group having a mercapto group), a polyorganosiloxane having a mercapto group introduced into a side chain and both ends of the organopolysiloxane (side chain both end type: in the formula (1), R ¹ R is R ² At least one of them is an organic group having a mercapto group, and R ³ ～R ⁵ At least one of them is an organic group having a mercapto group, R ⁶ ～R ⁸ At least one of them is an organic group having a mercapto group), and the like. Among them, the side chain type is preferable in that the polyorganosiloxane is easily biased to be distributed on the release surface side of the release agent layer, and the release property is more excellent.

Examples of the organic group among the organic groups having a mercapto group include an alkylene group, a polyester group, a polyether group, and the like, and among them, an alkylene group is preferable.

Examples of the alkyl group having no mercapto group include alkyl groups having 1 to 12 carbon atoms, specifically methyl groups, ethyl groups, propyl groups, butyl groups, pentyl groups, hexyl groups, octyl groups, and the like, and methyl groups are particularly preferred. Examples of the organic group having no mercapto group include various organic groups having a branched structure as appropriate, in addition to a polyester group, a polyether group and an alkylene group.

The mercapto group-introduced amount (functional group equivalent) in the mercapto group-containing polyorganosiloxane is preferably 50,000g/mol or less, and particularly preferably 30,000g/mol or less. By making the functional group equivalent of 50,000g/mol or less, compatibility with other components in the stripper composition becomes appropriate, and the stripping property becomes more excellent. The functional group equivalent is preferably 10.0g/mol or more, and particularly preferably 100g/mol or more. When the functional group equivalent is 10.0g/mol or more, a good coating film can be effectively formed when the coating film of the release agent composition is cured.

The weight average molecular weight of the polyorganosiloxane is preferably 1000 or more, particularly preferably 2000 or more, and further preferably 3000 or more. The weight average molecular weight is preferably 50000 or less, particularly preferably 40000 or less, and further preferably 30000 or less. By setting the weight average molecular weight to 1000 or more, the desired peelability can be easily and effectively achieved. Further, when the weight average molecular weight is 50000 or less, the coating liquid of the release agent composition is excellent in coating property on the substrate, and the occurrence of streaks, defects, and the like on the release surface of the formed release agent layer can be effectively suppressed.

The blending amount of the mercapto group-containing polyorganosiloxane in the release agent composition is preferably 0.05 mass% or more, particularly preferably 0.1 mass% or more, and further preferably 0.15 mass% or more, with respect to the release film of the present embodiment. The blending amount of the mercapto group-containing polyorganosiloxane in the stripper composition is preferably 2.0 mass% or less, particularly preferably 1.5 mass% or less, and further preferably 0.8 mass% or less. By making the blending amount of the mercapto group-containing polyorganosiloxane within the above range, the release film easily realizes excellent releasability.

(3) Crosslinking agent

The release agent composition may contain a crosslinking agent, and in particular, when the active energy ray-curable component has the above-described reactive group, the release agent composition preferably contains a crosslinking agent. When the active energy ray-curable component has the reactive group, the reactive group of the active energy ray-curable component can react with the crosslinking agent to form a three-dimensional network structure. Thus, the release film of the present embodiment has a more moderate hardness of the release agent layer, and as a result, more excellent releasability can be exhibited.

Examples of the crosslinking agent include isocyanate crosslinking agents, epoxy crosslinking agents, amine crosslinking agents, melamine crosslinking agents, aziridine crosslinking agents, hydrazine crosslinking agents, aldehyde crosslinking agents, oxazoline crosslinking agents, metal alkoxide crosslinking agents, metal chelate crosslinking agents, metal salt crosslinking agents, and ammonium salt crosslinking agents. Among them, when the active energy ray-curable component contains a hydroxyl group, an isocyanate-based crosslinking agent having excellent reactivity with the hydroxyl group is preferably used as the crosslinking agent. By using the isocyanate-based crosslinking agent, the urethane bond between the hydroxyl group in the active energy ray-curable component and the isocyanate group in the isocyanate-based crosslinking agent is formed, and simultaneously, the reaction between the mercapto group in the mercapto group-containing polyorganosiloxane and the isocyanate group in the isocyanate-based crosslinking agent is performed, whereby the three-dimensional network structure can be more effectively formed, and the stripper layer having a suitable hardness can be formed. In addition, the polyorganosiloxane is well fixed to the outermost surface of the three-dimensional network structure, and movement of the polyorganosiloxane to the adherend side can be effectively suppressed. In addition, the crosslinking agent may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

Preferable examples of the isocyanate-based crosslinking agent include polyisocyanate compounds having a plurality of isocyanate groups. Examples of the polyisocyanate compound include aromatic polyisocyanates such as toluene diisocyanate, diphenylmethane diisocyanate and m-xylylene isocyanate, aliphatic polyisocyanates such as hexamethylene diisocyanate, alicyclic polyisocyanates such as isophorone diisocyanate and hydrogenated diphenylmethane diisocyanate, and the like, and biuret, isocyanurate, and adducts of these compounds with low-molecular active hydrogen-containing compounds such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, castor oil, and the like. Among them, the isocyanurate of the polyisocyanate is preferable, the isocyanurate of the diisocyanate is particularly preferable, and the isocyanurate of the hexamethylene diisocyanate is further preferable, in view of excellent reactivity with hydroxyl groups and mercapto groups.

The blend amount of the crosslinking agent in the release agent composition is preferably 5.0 mass% or more, particularly preferably 10.0 mass% or more, with respect to the release film of the present embodiment. The blending amount of the crosslinking agent in the stripper composition is preferably 40.0 mass% or less, and particularly preferably 30.0 mass% or less. When the blending amount of the crosslinking agent is within the above range, the three-dimensional network structure can be formed more effectively, and the releasability becomes more excellent.

(4) Photopolymerization initiator

For the release film of the present embodiment, the release agent composition preferably contains a photopolymerization initiator. By containing the photopolymerization initiator, the active energy ray-curable component can be efficiently cured, or the polymerization curing time and the irradiation amount of active energy rays can be reduced.

As examples of the photopolymerization initiator, there are no particular limitations as long as the release agent composition can be used to form the release agent layer, examples thereof include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl ether, benzoin isobutyl ether, acetophenone, dimethylaminoacetophenone, 2-dimethoxy-2-phenylacetophenone, 2-diethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-1-phenylpropane-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- [4- (methylthio) phenyl ] -2-morpholino-propane-1-one, 4- (2-hydroxyethoxy) phenyl-2- (hydroxy-2-propyl) ketone, benzophenone, p-phenylbenzophenone, 4' -diethylaminobenzophenone, dichlorobenzophenone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-t-butylanthraquinone, 2-aminoanthraquinone, 2-methylthioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, 2, 4-dimethylthioxanthone, 2, 4-diethylthioxanthone, benzil dimethyl ketal, 2- [4- (methylthio) phenyl ] -2, 4-dimethylketal, 2- [ 2-hydroxy-2-propyl ] benzoyl ] 2- (2-methylbenzoyl) ketone, 4-trimethyl-2-phenylketone, 2-hydroxy-2-benzoyl ] 2-methylbenzoyl ] ketone, bis (2, 4, 6-trimethylbenzoyl) phenylphosphine oxide, and the like. These photopolymerization initiators may be used alone or in combination of 2 or more. Among them, 2-methyl-1- [4- (methylthio) phenyl ] -2-morpholino-propan-1-one is preferably used in view of being capable of efficiently curing the active energy ray-curable component.

The blend amount of the photopolymerization initiator in the release film of the present embodiment is preferably 1.0 mass% or more, and particularly preferably 3.0 mass% or more. The blending amount of the photopolymerization initiator in the stripper composition is preferably 20.0 mass% or less, and particularly preferably 10.0 mass% or less. By setting the blending amount of the photopolymerization initiator within the above range, the active energy ray-curable component can be efficiently cured, and the polymerization curing time and the irradiation amount of active energy rays can be reduced.

(5) Curing accelerator

For the release film of the present embodiment, the release agent composition preferably contains a curing accelerator. By containing the curing accelerator in the release agent composition, not only the reaction between the active energy ray-curable component and the crosslinking agent but also the reaction between the mercapto group-containing polyorganosiloxane and the crosslinking agent can be efficiently performed at the time of forming the release agent layer, whereby the release agent layer which is cured more favorably is easily formed, and as a result, the release film of the present embodiment exhibits more excellent releasability.

As examples of the curing accelerator, there are no particular restrictions on the release agent composition, as long as the release agent layer can be formed using, for example, titanium-based catalysts, aluminum-based catalysts, zirconium-based catalysts, boron trifluoride-based catalysts, tin-based catalysts, iron-based catalysts, and the like. These curing accelerators may be used alone or in combination of 2 or more.

The titanium-based catalyst is preferably titanium alkoxide, titanium chelate, or titanium (IV) chloride. The aluminum-based catalyst is preferably aluminum alkoxide, aluminum chelate, or aluminum (III) chloride. As the zirconium-based catalyst, zirconium alkoxide, zirconium chelate, zirconium (IV) chloride are preferable. As the above boron trifluoride catalyst, an amine complex or an alcohol complex of boron trifluoride is preferable.

As the titanium-based catalyst, a titanium chelate compound is particularly preferably used, and an organic titanium oxide having a structure of the following formula (2) is particularly preferably used. In the formula (2), R represents an alkyl group having 1 to 10 carbon atoms, R' represents a methyl group or an ethoxy group, and n represents an integer of 1 to 4.

Ti(O-R) _n (O-C(R’)CHCOCH ₃ ) ₍₄ -n)···(2)

Specific examples of the organic titanium oxide include titanium tetramethoxide, titanium tetraethoxide, titanium tetra-n-propoxide, titanium tetra-isopropoxide, titanium tetra-n-butoxide, titanium tetra-isobutanoxide, titanium tetra-t-butoxide, titanium tetra (2-ethylhexoxide) titanium isopropoxide, titanium (titanium isopropoxyoctylene glycolate) octadiol, titanium tetra (acetylacetonato), titanium tetra (ethoxyacetoacetide) (titanium tetrakis (ethyl acetoacetate)), titanium diisopropyloxide diacetone (diisopropoxytitanium bis (acetate)), titanium diisopropyloxide diacetone, titanium diisopropyloxide di (ethoxyacetoacetide), titanium di-n-butoxydiacetone, and di-n-butoxydi (ethoxyacetoacetide).

Among them, an organic titanium oxide is preferable as the organic titanium complex compound. As such an organic titanium complex, a titanium complex in which a β -dicarbonyl compound is used as a ligand is preferable from the viewpoint of moisture resistance (hydrolysis resistance) in the atmosphere. Examples of the β -dicarbonyl compound include β -diketones such as acetylacetone and benzoylacetone, and β -ketoesters such as ethyl acetoacetate, and among them, ethyl acetoacetate is preferable. Therefore, specifically, titanium diisopropoxydiacetylacetonate and diisopropoxybis (ethoxyacetoacetyl) phthalide are particularly preferable as the organic titanium oxide. In addition, the organic titanium oxide may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

The molecular weight of the organic titanium oxide is preferably 250 or more, particularly preferably 300 or more, and further preferably 400 or more. The molecular weight is preferably 750 or less, particularly preferably 600 or less, and further preferably 500 or less.

The blend amount of the curing accelerator in the release film of the present embodiment is preferably 0.1 mass% or more, particularly preferably 0.5 mass% or more. The blending amount of the curing accelerator in the stripper composition is preferably 7.0 mass% or less, and particularly preferably 5.0 mass% or less. By setting the blending amount of the curing accelerator within the above range, the reaction proceeds more efficiently, and the stripper layer has a more appropriate hardness, as a result, more excellent stripping performance can be exhibited.

(6) Other ingredients

The stripping agent composition may contain an antistatic agent, a reaction inhibitor, an adhesion improver, and the like in addition to the above components.

2-2 preparation of stripper composition

The release agent composition can be prepared by mixing the active energy ray-curable component and the mercapto group-containing polyorganosiloxane, and if necessary, mixing a crosslinking agent, a photopolymerization initiator, a curing accelerator, or other components. The resulting stripper composition can be diluted in a diluting solvent as needed to prepare a coating liquid.

Examples of the diluent solvent include aliphatic hydrocarbons such as hexane, heptane, and cyclohexane, aromatic hydrocarbons such as toluene and xylene, halogenated hydrocarbons such as methylene chloride and dichloroethane, alcohols such as methanol, ethanol, isopropyl alcohol, butanol and 1-methoxy-2-propanol, esters such as acetone, methyl ethyl ketone, 2-pentanone, isophorone and cyclohexanone, propylene glycol monomethyl ether acetate, ethyl acetate and butyl acetate, cellosolve solvents such as ethyl cellosolve, and mixtures of these solvents.

The concentration and viscosity of the coating liquid prepared in the above manner are not particularly limited as long as they are within a range where coating can be performed, and may be appropriately selected according to the situation. For example, the stripping agent composition is diluted so that the concentration is 3 mass% or more and 60 mass% or less. In addition, in order to obtain the coating liquid, a diluent solvent or the like is not necessarily added, and the diluent solvent may not be added as long as the stripper composition has a viscosity or the like that enables coating.

2-3 thickness of stripper layer

In the release sheet of the present embodiment, the thickness of the release agent layer is preferably 10nm or more, and particularly preferably 50nm or more. The thickness is preferably 10 μm or less, and particularly preferably 5 μm or less. The thickness of the release agent layer is 10nm or more, whereby the desired releasability can be easily achieved. In addition, by setting the thickness of the release agent layer to 10 μm or less, the release agent layer can be easily cured satisfactorily.

3. Physical Properties of Release film

In the release film of the present embodiment, the release force required for peeling the release film from the ceramic green sheet molded on the release surface of the release film can be appropriately set, but is preferably 40.0mN/40mm or less. With respect to this peeling force, the release film according to the present embodiment can exhibit the peelability as described above well by forming the release agent layer using the release agent composition described above. The lower limit of the peeling force is not particularly limited, but is usually preferably 3.0mN/40mm or more, particularly preferably 5.0mN/40mm or more. The method for measuring the peeling force required for peeling the release film from the ceramic green sheet is as follows.

4. Method for producing release film

The release film of the present embodiment can be manufactured by a conventional method. For example, the above-mentioned stripper composition is diluted with a diluting solvent to prepare a coating liquid, and the coating liquid is applied to one side of a substrate to form a coating film, and then the coating film is heated. The coating film may also be dried prior to this heating. After heating, the coating film is irradiated with active energy rays.

The method of forming the coating film is not particularly limited, and as a method of applying the coating liquid of the release agent composition, for example, a gravure coating method, a bar coating method, a spray coating method, a spin coating method, a doctor blade coating method, a roll coating method, a die coating method, or the like can be used.

Either or both of the heating after the formation of the coating film and the irradiation with active energy rays may be performed first or both of them may be performed simultaneously.

As the active energy ray used for irradiation with the active energy ray, for example, ultraviolet rays, electron rays, or the like can be used, and particularly, ultraviolet rays which are easy to handle are preferable.

The irradiation of ultraviolet rays can be performed by a high-pressure mercury lamp, a xenon lamp, or the like. The amount of ultraviolet light is preferably 10mJ/cm ² The above is particularly preferably 30mJ/cm ² The above. Further, the light quantity is preferably 1000mJ/cm ² Hereinafter, 500mJ/cm is particularly preferred ² The following is given. By performing ultraviolet irradiation under the conditions within the above-described range, the release agent composition can be cured more favorably, and a favorable release agent layer can be formed effectively.

The irradiation of the electron beam may be performed by an electron beam accelerator or the like, and the irradiation amount of the electron beam is preferably 0.1kGy or more, and particularly preferably 1kGy or more. The irradiation amount is preferably 50kGy or less, and particularly preferably 30kGy or less.

The heating temperature is preferably 80℃or higher, and particularly preferably 100℃or higher. The temperature is preferably 180℃or lower, and particularly preferably 150℃or lower. The heating time is preferably 3 seconds or more, and particularly preferably 5 seconds or more. The heating time is preferably 120 seconds or less, and particularly preferably 60 seconds or less. The heating step may also be used as a heat drying treatment for volatilizing the solvent in the coating liquid from the coating film.

According to the above production method, the active energy ray-curable component can be efficiently cured by irradiation with energy rays, and the reaction between the active energy ray-curable component and the crosslinking agent, particularly the reaction between the active energy ray-curable component and the mercapto group-containing polyorganosiloxane and the crosslinking agent can be efficiently performed by heating. Thus, the polyorganosiloxane is easily biased to be distributed on the surface of the release agent layer, and the release agent layer is made to have a moderate hardness. As a result, the obtained release film exhibits more excellent releasability.

5. Application method of release film

The release film of the present embodiment can be suitably used for manufacturing a ceramic green sheet. For example, a ceramic green sheet to which a release film is attached can be produced by applying a ceramic slurry containing a ceramic material such as barium titanate or titanium oxide to a release surface of the release film, and then drying the ceramic slurry. In addition, the release film of the present embodiment can also be used as a release film of a usual adhesive sheet.

As described above, the release film of the present embodiment can exhibit excellent releasability. Therefore, by using the release film according to the present embodiment, occurrence of breakage or the like can be suppressed, and a ceramic green sheet excellent in quality can be produced.

The embodiments described above are described for easy understanding of the present invention, and are not described for limiting the present invention. Accordingly, each element disclosed in the above embodiments also includes all design changes and equivalents falling within the technical scope of the present invention.

For example, another layer such as an antistatic layer may be provided on the surface of the base material opposite to the release agent layer or between the base material and the release agent layer in the release film.

Examples

The present invention will be described more specifically with reference to examples, but the scope of the present invention is not limited to these examples.

Example 1

A mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate (SHIN-NAKAMURA CHEMICAL CO, LTD. Manufactured by 71.8 parts by mass (calculated as solid content; the same applies hereinafter), product name "A-TMM-3L",3 functionality, hydroxyl value: 105mgKOH/g, viscosity (25 ℃ C.) 520 mPa.s), 0.25 part by mass of a mercapto group-containing polyorganosiloxane (manufactured by SHIN-Etsu Chemical Co., ltd. Manufactured by SHD. Manufactured by SHIN-NAKAMURA CHEMICAL CO., product name "KF-2001", side chain type, functional group equivalent of mercapto group: 1900g/mol, viscosity (25 ℃ C.) 200mm was prepared ² 19.3 parts by mass of an isocyanurate body of hexamethylene diisocyanate as a crosslinking agent (manufactured by Asahi Kasei corporation, product name "MFA-75B"), 7.2 parts by mass of 2-methyl-1- [4- (methylsulfanyl) phenyl as a photopolymerization initiator]The stripping agent composition comprising 2-morpholino-propan-1-one (manufactured by IGM Resins b.v., product name "Omnirad 907"), and 1.4 parts by mass of diisopropoxybis (ethoxyacetoacetyl) phthalide (Matsumoto Fine Chemical co., manufactured by ltd., product name "TC-750") as a curing accelerator was mixed in a mixed solvent (mixing ratio 50:50) of Methyl Ethyl Ketone (MEK) and propylene glycol monomethyl ether acetate to obtain a coating liquid having a solid content of 17% by mass.

The obtained coating liquid of the remover composition was applied to one side of a biaxially stretched polyethylene terephthalate film (manufactured by TORAY INDUSTRIES, INC., product name "LumirrorS 10", thickness: 23 μm, maximum protrusion height Rp of both sides: 452 nm) as a substrate using a Meyer bar #5 to form a coating film. Self-coating after heating the coating film at 120℃for 15 secondsThe side of the film opposite to the substrate was irradiated with ultraviolet rays (illuminance: 1000mW/cm ² Light amount: 50mJ/cm ² ) A stripping agent layer having a thickness of 1.0 μm was formed. Thus, a release film obtained by laminating a base material and a release agent layer was obtained.

Examples 2 to 7

A release film was produced in the same manner as in example 1, except that the types of active energy ray-curable components, the blending amounts of active energy ray-curable components, the content of polyorganosiloxane, and the blending amount of the crosslinking agent in the release agent composition were changed to those shown in table 1.

Comparative example 1

A mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate (SHIN-NAKAMURA CHEMICAL CO, LTD. Manufactured by the product name "A-TMM-3L",3 functionality, hydroxyl value: 105mgKOH/g, viscosity (25 ℃ C.) 520 mPa.s), 0.22 parts by mass of a methanol group-containing (carbnol) polyorganosiloxane (SHIN-Etsu Chemical Co., ltd., manufactured by the product name "KF-6002", both ends, hydroxyl value: 35mgKOH/g, viscosity (25 ℃ C.) 70 mm) was used as an active energy ray-curable component ² 19.3 parts by mass of an isocyanurate body of hexamethylene diisocyanate as a crosslinking agent (manufactured by Asahi Kasei corporation, product name "MFA-75B"), 7.2 parts by mass of 2-methyl-1- [4- (methylsulfanyl) phenyl as a photopolymerization initiator]The stripping agent composition comprising 1.4 parts by mass of diisopropoxybis (ethoxyacetoacetyl) phthalide (Matsumoto Fine Chemical Co., ltd., product name: TC-750) as a curing accelerator and 2-morpholino-propan-1-one (manufactured by IGM Resins B.V., product name: omnirad 907) was mixed in a mixed solvent (mixing ratio: 50:50) of Methyl Ethyl Ketone (MEK) and propylene glycol monomethyl ether acetate to obtain a coating liquid having a solid content of 17% by mass.

The obtained coating liquid of the stripper composition was coated on one surface of a biaxially stretched polyethylene terephthalate film (manufactured by TORAY INDUSTRIES, INC., product name "LumirrorS 10", thickness: 23 μm, maximum protrusion height Rp of both surfaces: 452 nm) as a substrate using a Meyer rod #5A coating film was formed thereon. After heating the coating film at 120℃for 15 seconds, ultraviolet rays (light amount: 100 mJ/cm) were irradiated from the side of the coating film opposite to the base material ² ) A stripping agent layer having a thickness of 1.0 μm was formed. Thus, a release film obtained by laminating a base material and a release agent layer was obtained.

Comparative example 2

A release film was produced in the same manner as in comparative example 1, except that the types of the active energy ray-curable components in the release agent composition were changed to those shown in table 1.

Test example 1 (measurement of peel force of ceramic green sheet)

100 parts by mass of barium titanate powder (BaTiO) was added to 135 parts by mass of a mixed solution of toluene and ethanol (mass ratio 6:4) ₃ The method comprises the steps of carrying out a first treatment on the surface of the SAKAI CHEMICAL INDUSTRY CO., LTD. Manufactured by Kantu Kagaku, product name "BT-03"), 8 parts by mass of a polyvinyl butyral resin (SEKISUI CHEMICAL CO., manufactured by LTD. Manufactured by SEKISUI CHEMICAL CO., product name "S-LEC B.K BM-2"), and 4 parts by mass of dioctyl phthalate (manufactured by KANTO KAGAKU, product name "dioctyl phthalate deer 1 grade") as a plasticizer were mixed and dispersed by a ball mill to prepare a ceramic slurry.

The ceramic slurry was uniformly applied to the release surfaces of the release agent layers of the release films obtained in examples and comparative examples using a coater (applicator), and then dried at 65 ℃ for 1 minute using a dryer. Thus, a release film with a ceramic green sheet having a thickness of 15 μm was formed on the release film.

The release film with the ceramic green sheet was allowed to stand at room temperature of 23℃under an atmosphere of 50% RH for 24 hours. Then, a 5mm wide acrylic adhesive tape (manufactured by Nitto Denko corporation, product name "31B tape") was attached to one end of the ceramic green sheet on the short side of the side opposite to the release sheet by cutting at a size of 100mm in the longitudinal direction and 40mm in the width direction. This was used as a measurement sample.

The release film side of the measurement sample was fixed to a plate with a double-sided tape, and the plate was horizontally set in a release tester (manufactured by SHIMADZU CORPORATION under the product name "AGS-20 NX") so that the measurement sample was upper. Then, the end of the ceramic green sheet on the side to which the acrylic pressure-sensitive adhesive tape was attached was peeled off from the release film, and the end was mounted on a jig of a peel tester. In this state, the ceramic green sheet was stretched in the vertical direction at a peeling speed of 200mm/min (90 DEG peeling method), and the peeling film and the ceramic green sheet were peeled, whereby the force (peeling force; mN/40 mm) required for peeling was measured.

Details such as abbreviations shown in table 1 are as follows.

[ active energy ray-curable component ]

A-TMM-3L: mixtures of pentaerythritol triacrylate and pentaerythritol tetraacrylate (SHIN-NAKAMURA CHEMICAL CO, LTD. Manufactured by the product name "A-TMM-3L",3 functionality, hydroxyl number: 105mgKOH/g, viscosity (25 ℃ C.) 520 mPa.s)

A-9550: mixtures of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (SHIN-NAKAMURA CHEMICAL CO, manufactured by LTD. Product name "A-9550", functionality 5-6, hydroxyl number 50mgKOH/g, viscosity (25 ℃ C.) 6500 mPa.s)

Polyorganosiloxane

KF-2001: mercapto group-containing polyorganosiloxane (Shin-Etsu Chemical Co., ltd., product name "KF-2001", side chain type, mercapto group-functional group equivalent 1900g/mol, dynamic viscosity (25 ℃ C.) 200 mm) ² /s)

KF-6002: methanol group-containing polyorganosiloxane (Shin-Etsu Chemical Co., ltd., product name "KF-6002", hydroxyl value 35mgKOH/g, both ends, dynamic viscosity (25 ℃ C.) 70 mm) ² /s)

TABLE 1

As is clear from table 1, the release film obtained in examples exhibited excellent releasability.

Industrial applicability

The release film of the present invention is suitable for use as a release film or the like that can be used for the production of ceramic green sheets.

Claims

1. A release film comprising a base material and a release agent layer provided on at least one surface side of the base material, characterized in that,

the release agent layer is formed from a release agent composition containing an active energy ray-curable component and a mercapto group-containing polyorganosiloxane.

2. The release film of claim 1, wherein the mercapto group of the mercapto group-containing polyorganosiloxane is present in a side chain.

3. The release film according to claim 1 or 2, wherein the mercapto group-containing polyorganosiloxane has a functional group equivalent for mercapto groups of 10g/mol or more and 50,000g/mol or less.

4. A release film according to any one of claims 1 to 3, wherein the release agent composition comprises a cross-linking agent.

5. The release film of claim 4, wherein the crosslinker is an isocyanate-based crosslinker.

6. The release film according to any one of claims 1 to 5, wherein the active energy ray-curable component is a polyfunctional (meth) acrylate.

7. The release film according to claim 6, wherein the polyfunctional (meth) acrylate has 3 to 6 functional groups.

8. The release film according to any one of claims 1 to 7, which is used in a ceramic green sheet production process.