CN111295272A

CN111295272A - Release film for producing ceramic green sheet

Info

Publication number: CN111295272A
Application number: CN201880070851.XA
Authority: CN
Inventors: 柴田悠介; 松尾有加
Original assignee: Toyobo Co Ltd
Current assignee: Toyobo Co Ltd
Priority date: 2017-11-02
Filing date: 2018-10-31
Publication date: 2020-06-16
Anticipated expiration: 2038-10-31
Also published as: WO2019088184A1; SG11202003421PA; JPWO2019088184A1; KR102422462B1; PH12020550508A1; CN111295272B; KR20200080280A; JP6610810B2

Abstract

[ problem ] to]Provided is an excellent release film for producing a ceramic green sheet, which can prevent pinholes, partial thickness unevenness, and the like, and reduce unwinding electrification even when the ceramic green sheet is made thin. [ solution ]]A release film for producing a ceramic green sheet, comprising a polyester film substantially free of inorganic particles as a base material, a release coating layer provided on one surface of the base material, and an easy-to-slide coating layer containing particles provided on the other surface of the base material, the easy-to-slide coating layerHas a domain surface average roughness (Sa) of 1nm to 25nm, a maximum protrusion height (P) of 60nm to 500nm, and a contour unit average width (RSm) of 10 [ mu ] m or less, and has a March Hardness (HM) of 150N/mm for a single film of a mixed composition of a resin and a crosslinking agent of the easy-slip coating layer²The above, and the elastic deformation power (η it) is 28% or more.

Description

Release film for producing ceramic green sheet

Technical Field

The present invention relates to a release film for producing a ceramic green sheet. More specifically, the present invention relates to: when the ceramic green sheet is made thin, a release film for producing a ceramic green sheet, which prevents pinholes, partial thickness unevenness, and the like, and reduces the occurrence of unwinding electrification, may be provided.

Background

Conventionally, the following techniques have been disclosed: by making the surface roughness of the surface (back surface) opposite to the surface of the base film on which the release agent layer is provided thicker, the problem that the surface and the back surface of the release film for ceramic green sheet production adhere (block) when the release film for ceramic green sheet production is stored in a wound state is eliminated (for example, see patent document 1). However, the above-described prior art has the following problems: since the projection on the back surface is large, pinholes are generated and the thickness of the part is not uniform.

Therefore, in order to reduce the height of the protrusion on the back surface, the following technique is disclosed: the coating layer fills the protrusions on the back surface, and thus it is desired to prevent occurrence of pinholes and partial thickness unevenness in the ceramic green sheet (see, for example, patent document 2). However, according to the above-mentioned conventional technique, although the projection height is low, the projection density is low, and therefore, when the pressure applied to the projections is large and the ceramic green sheet is further thinned, there is a problem that pinholes are generated.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2003-203822

Patent document 2: japanese patent laid-open No. 2014-144636

Disclosure of Invention

Problems to be solved by the invention

The present invention was made in view of the above-mentioned problems of the prior art. That is, an object of the present invention is to provide an excellent release film for producing a ceramic green sheet, which can prevent pinholes, partial thickness unevenness, and the like and reduce unwinding electrification even when the ceramic green sheet is made thin.

Means for solving the problems

The present inventors have conducted intensive studies to achieve the above object, and as a result, the present invention has been completed. That is, the present invention includes the following configurations.

1. A release film for producing a ceramic green sheet, comprising a polyester film substantially free of inorganic particles as a base material, a release coating layer on one surface of the base material, and an easy-slip coating layer comprising particles on the other surface, wherein the easy-slip coating layer has a regional surface average roughness (Sa) of 1 to 25nm, a maximum protrusion height (P) of 60 to 500nm, and an average width of profile cells (RSm) of 10 [ mu ] m or less, and wherein a mixed composition single film of a resin and a crosslinking agent of the easy-slip coating layer has a Mahalanobis Hardness (HM) of 150N/mm²The above, and the elastic deformation power (η it) is 28% or more.

2. The release film for manufacturing a ceramic green sheet according to the above item 1, wherein the easy-slip coating layer is obtained by curing a composition containing an acrylic resin and at least 1 crosslinking agent selected from an oxazoline crosslinking agent and a carbodiimide crosslinking agent.

3. The release film for producing a ceramic green sheet according to the above 1 or 2, wherein the thickness of the easy-slip coating layer is 0.001 μm or more and 2 μm or less.

4. A method for producing a ceramic green sheet, which comprises using the release film for producing a ceramic green sheet described in any one of the above items 1 to 3.

5. The method for producing a ceramic green sheet according to the above 4, wherein the thickness of the produced ceramic green sheet is 0.2 μm or more and 2.0 μm or less.

6. A method for producing a ceramic capacitor, which comprises using the method for producing a ceramic green sheet according to the above 4 or 5.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, there can be provided an excellent release film for producing a ceramic green sheet, which can prevent pinholes, partial thickness unevenness, and the like, and can reduce unwinding electrification, even when the ceramic green sheet is made thin.

Detailed Description

The present invention will be described in detail below.

The release film for producing a ceramic green sheet (hereinafter, may be simply referred to as a release film) of the present invention is a release film having a release coating layer on one surface of a biaxially oriented polyester film as a base film and an easily slippery coating layer containing particles on the other surface.

The present inventors have proposed a release film that can cope with recent thinning of green sheets by setting the average width (RSm) of profile cells on an easily-coated surface to a specific range in order to increase the protrusion density of an easily-sliding surface (international application No. PCT/JP 2017/017354). According to the above-described technique, it is preferable to increase the density of the projections so that the winding performance can be maintained at a low projection height, and pinholes and partial thickness unevenness can be prevented.

In the present invention, the mixed composition of the resin and the crosslinking agent of the easy-slip coating layer as the easy-slip coating layer has a Mohs Hardness (HM) of 150N/mm²Since the hardness of the easy-to-slip coating layer is moderately high and the pressure is weakened, the deformation of the easy-to-slip coating layer occurring when the easy-to-slip coating layer comes into contact with the release coating layer is immediately recovered, because the elastic deformation power η it is 28% or more.

The high martensitic hardness is advantageous in that the easily slippery coating layer is less likely to deform during winding after the coating of the release coating layer.

The elastic deformation power η it is high, that is, the ratio of elastic deformation is larger than plastic deformation in applied power, and when the pressure between the easy-slip coating layer deformed by contact with the release coating layer and the release coating layer becomes weak, the deformation is immediately recovered.

When the diameter of the film roll is reduced during unwinding of the film roll, the deformation of the easy-to-slip coating layer is restored to the state of the roll before unwinding, and the contact area between the easy-to-slip coating layer and the release layer during unwinding is reduced.

It is known that the larger the contact area of 2 persons in normal contact, the larger the electrification at the time of peeling of 2 persons. If the amount of deformation of the easy-to-slip coating layer is small and the recovery of the deformation is fast, the contact area between the easy-to-slip coating layer and the release layer when the release film roll is unwound is reduced, and therefore, the unwinding electrification when the release film roll is unwound can be suppressed, which is preferable.

It is preferable that the unwinding electrification is small because the adhesion of an environmental foreign substance to the release surface can be prevented to prevent the quality abnormality of the ceramic capacitor. In recent years, as the trend toward the thinning of ceramic sheets, the adhesion of even small environmental foreign substances to the release surface, which has not been a problem in the past, is a problem, and therefore, a release film having a composition of an easy-to-slip coating layer defined in the present invention is effective, and further, the following features are preferably added: the average width (RSm) of the contour elements of the slippery coating layer is made to fall within a specific range.

(base film)

The film preferably used as the substrate in the present invention is a film made of a polyester resin, and is preferably a polyester film mainly containing at least 1 selected from the group consisting of polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate. Further, the polyester may be a film formed by copolymerizing a third component monomer as a part of the dicarboxylic acid component or the diol component of the polyester as described above. Among these polyester films, polyethylene terephthalate films are most preferable from the viewpoint of balance between physical properties and cost.

The polyester film may be a single layer or a multilayer. In addition, the polyester resin may contain various additives as needed in each of these layers as long as the desired effects of the present invention are exhibited. Examples of the additives include antioxidants, light stabilizers, anti-gelling agents, organic wetting agents, antistatic agents, and ultraviolet absorbers.

(easy slip coating layer)

The release film of the present invention has an easily-slipping coating layer on one surface of the polyester base film. The slip-coat layer preferably contains at least a binder resin and particles.

In the present invention, the Martensitic Hardness (HM) of the mixed composition of the resin of the easily slippery coating layer and the crosslinking agent is preferably 150N/mm²The above. Further preferably, the March Hardness (HM) is 200N/mm²The above. The mixed composition of the resin of the easy-slip coating layer and the crosslinking agent has a Mohs Hardness (HM) of 150N/mm²In the above case, the hardness of the easy-slip coating layer is preferably increased as appropriate.

In the present invention, the Martensitic Hardness (HM) of the mixed composition of the resin of the easily slippery coating layer and the crosslinking agent is preferably 600N/mm²The following. Further preferably, the March Hardness (HM) is 500N/mm²The following. The mixed composition of the resin of the easy-slip coating layer and the crosslinking agent has a Mohs Hardness (HM) of 600N/mm²In the following case, it is preferable that the surface of the release coating layer is not damaged by scratches, dents, and the like.

In the present invention, the elastic deformation power (η it) of the single film of the mixed composition of the resin of the easily slippery coating layer and the crosslinking agent is preferably 28% or more, and if the elastic deformation power (η it) is 30% or more, more preferably, if the elastic deformation power (η it) of the single film of the mixed composition of the resin of the easily slippery coating layer and the crosslinking agent is 28% or more, the pressure during unwinding of the film roll becomes small, and the deformation of the easily slippery coating layer generated when the easily slippery coating layer comes into contact with the release coating layer is immediately recovered.

In the present invention, the elastic deformation power (η it) of the mixed composition single film of the resin and the crosslinking agent of the slip-resistant coating layer is preferably 90% or less, and the elastic deformation power (η it) is more preferably 80% or less, and the elastic deformation power (η it) of the mixed composition single film of the resin and the crosslinking agent of the slip-resistant coating layer is preferably 90% or less, because the plastic deformation of the slip-resistant coating layer is moderate, the friction coefficient with the release layer is excessively low, and the possibility of occurrence of roll misalignment and the like is reduced.

(Binder resin in easy-slip coat layer)

The binder resin constituting the easy-slip coating layer in the present invention is not particularly limited, and specific examples of the polymer include polyester resins, acrylic resins, polyurethane resins, polyvinyl resins (e.g., polyvinyl alcohol), polyalkylene glycols, polyalkylene imines, methyl cellulose, hydroxy cellulose, and starches. Among these, polyester resins and acrylic resins are preferably used in order to achieve the above-mentioned mohs hardness and elastic deformation power. Among them, acrylic resins are particularly preferably used. The acrylic resin is preferably an acrylic resin having a hydroxyl group and a carboxyl group in the molecule. The structural unit having a hydroxyl group is more preferably contained in an amount of 20 to 90 mol% based on 100 mol% of the total structural units. When the content of the structural unit having a hydroxyl group is 20 mol% or more, the water solubility of the acrylic resin can be appropriately maintained, and it is preferable. On the other hand, if it is 90 mol% or less, the hydroxyl groups of the acrylic resin do not extremely interact with the particles contained in the easy-slip coating layer, and the particles are uniformly dispersed, which is preferable.

In order to introduce a hydroxyl group into the acrylic resin, a monomer having a hydroxyl group such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, or the like, γ -butyrolactone, a ring-opening adduct of e-caprolactone and 2-hydroxyethyl (meth) acrylate, or the like can be used as a copolymerization component. Among these, 2-hydroxyethyl (meth) acrylate is preferable in terms of not hindering water solubility. These may be used in combination of 2 or more.

The hydroxyl value of the acrylic resin is preferably 2mgKOH/g or more, more preferably 5mgKOH/g or more, and still more preferably 10mgKOH/g or more. When the hydroxyl value of the acrylic resin is 2mgKOH/g or more, the water solubility of the acrylic resin is favorable and preferable.

The hydroxyl value of the acrylic resin is preferably 250mgKOH/g or less, more preferably 230mgKOH/g or less, and still more preferably 200mgKOH/g or less. When the hydroxyl value of the acrylic resin is 250mgKOH/g or less, the hydroxyl group of the acrylic resin does not extremely interact with the particles contained in the easily slippery coating layer, and the particles are uniformly dispersed, which is preferable.

The acrylic resin used in the present invention is preferably a resin having a carboxyl group in addition to a hydroxyl group. By having a carboxyl group, a crosslinked structure with a crosslinking agent can be formed, and water solubility can be easily imparted. Examples thereof include carboxyl group-containing monomers such as (meth) acrylic acid, crotonic acid, itaconic acid, maleic acid, and fumaric acid, and acid anhydride group-containing monomers such as maleic anhydride and itaconic anhydride.

The monomer having a carboxyl group is preferably 4 mol% or more, more preferably 10 mol% or more, out of 100 mol% of the total structural units of the acrylic resin. When the amount is 4 mol% or more, it becomes easy to form a crosslinked structure in the slip-resistant coating layer and to impart water solubility, and therefore, it is preferable. The monomer having a carboxyl group is preferably 65 mol% or less, more preferably 50 mol% or less. If the amount is 65 mol% or less, the Tg of the obtained coating film is not too high relative to the suitable range described later, and the film formability and the stretchability in inline coating are good, so that it is preferable.

In order to exhibit good water solubility, it is preferable to neutralize the carboxyl group introduced into the acrylic resin by copolymerization of acrylic acid and methacrylic acid. As the alkaline neutralizing agent, there are: and amine compounds such as ammonia, trimethylamine, triethylamine and dimethylaminoethanol, and inorganic basic substances such as potassium hydroxide and sodium hydroxide, among which amine compounds are preferably used as the neutralizing agent for the ease of volatilization of the neutralizing agent and the ease of formation of a crosslinked structure. The neutralization rate is preferably 30 to 95 mol%, more preferably 40 to 90 mol%. When the neutralization degree is 30 mol% or more, the water solubility of the acrylic resin is sufficient, the acrylic resin is easily dissolved in preparing the coating liquid, or the coated surface after drying is not likely to be whitened, and therefore, it is preferable. On the other hand, if the neutralization degree is 95 mol% or less, the water solubility is not too high, and mixing of alcohol and the like becomes easy in preparation of the coating liquid, which is preferable.

The acid value of the acrylic resin is preferably 40mgKOH/g or more, more preferably 50mgKOH/g or more, and still more preferably 60mgKOH/g or more. When the acid value of the acrylic resin is 40mgKOH/g or more, the crosslinking points with the oxazoline crosslinking agent or the carbodiimide crosslinking agent increase, and therefore, a strong coating film having a higher crosslinking density can be obtained, which is preferable.

The acid value of the acrylic resin is preferably 400mgKOH/g or less, more preferably 350mgKOH/g or less, and still more preferably 300mgKOH/g or less. When the acid value of the acrylic resin is 400mgKOH/g or less, the carboxyl group of the acrylic resin does not extremely interact with the particles contained in the easy-slip coating layer, and the particles are uniformly dispersed, which is preferable. When the dispersibility of the particles is good, coarse protrusions are not formed on the surface of the easily-slippery coating layer, and pinholes are not formed in the ceramic sheet, which is preferable.

The glass transition temperature (Tg) of the acrylic resin is preferably 50 ℃ or higher, more preferably 55 ℃ or higher, and still more preferably 60 ℃ or higher. When the glass transition temperature of the acrylic resin is 50 ℃ or higher, the hardness of the easy-slip coating layer is suitably increased.

The glass transition temperature (Tg) of the acrylic resin is preferably 110 ℃ or lower, more preferably 105 ℃ or lower, and still more preferably 100 ℃ or lower. When the glass transition temperature of the acrylic resin is 110 ℃ or lower, the coating film is uniformly stretched without causing cracks in the coating film in the stretching step after the easy-slip coating layer is applied, and therefore, it is preferable.

As the Tg adjusting monomer to be copolymerized so that Tg is in the above range, a (meth) acrylic monomer or a non-acrylic vinyl monomer can be used. Specific examples of the (meth) acrylic monomer include alkyl (meth) acrylates such as methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, n-pentyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, and stearyl (meth) acrylate; nitrogen-containing acrylic monomers such as (meth) acrylamide, diacetone acrylamide, n-methylolacrylamide, and (meth) acrylonitrile; vinyl methacrylate, etc., and 1 or more or 2 kinds thereof may be used.

Examples of the non-acrylic vinyl monomer include styrene monomers such as styrene, α -methylstyrene, vinyltoluene (a mixture of m-methylstyrene and p-methylstyrene), and chlorostyrene, vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl caproate, vinyl caprylate, vinyl caprate, vinyl laurate, vinyl myristate, vinyl palmitate, vinyl stearate, vinyl cyclohexanecarboxylate, vinyl pivalate, vinyl caprylate, vinyl monochloroacetate, divinyl adipate, vinyl crotonate, vinyl sorbate, vinyl benzoate, and vinyl cinnamate, and 1 or 2 or more kinds of halogenated vinyl monomers such as vinyl chloride and vinylidene chloride can be used.

The Tg adjusting monomer is preferably determined by determining an appropriate amount of the hydroxyl group-containing monomer and the carboxyl group-containing monomer, and setting the remaining amount thereof. The Tg of the copolymer was determined by the following Fox equation.

Wn: mass fraction (mass%) of each monomer

Tgn: tg (K) of homopolymer of each monomer

As the monomer to be copolymerized for adjusting Tg, a component for lowering surface free energy such as a long chain alkyl group may be introduced. The acrylic resin into which a long-chain alkyl group is introduced is preferably one having an alkyl group having about 8 to 20 carbon atoms in a side chain of the acrylic resin. In addition, it is also possible to suitably use: a polymer having a (meth) acrylate as a main repeating unit, wherein the ester-exchanged portion contains a long-chain alkyl group having 8 to 20 carbon atoms.

The monomer having a long-chain alkyl group among the monomers copolymerized for adjusting Tg is preferably 50 mol% or less, more preferably 40 mol% or less, out of 100 mol% of the total structural units of the acrylic resin. If the amount is 50 mol% or less, the Tg of the resulting coating film is not excessively lowered with respect to the suitable range, and the hardness of the coating film can be maintained at a high level, which is preferable. In the present invention, if the Tg can be maintained within an appropriate range, the amount of the monomer having a long chain alkyl group may be 0 mol%, and if the amount is 5 mol% or more, the effect of Tg adjustment of the acrylic resin becomes clear and preferable.

The acrylic resin used in the present invention can be obtained by known radical polymerization. Any of emulsion polymerization, suspension polymerization, solution polymerization, bulk polymerization, and the like can be used. From the viewpoint of handling, solution polymerization is preferable. Examples of the water-soluble organic solvent that can be used in the solution polymerization include ethylene glycol n-butyl ether, isopropyl alcohol, ethanol, n-methylpyrrolidone, tetrahydrofuran, 1, 4-dioxane, 1, 3-dioxolane, methyl cellosolve, ethyl carbitol, butyl carbitol, propylene glycol monopropyl ether, and propylene glycol monobutyl ether. They may be used in admixture with water.

The polymerization initiator may be any known compound that generates a radical, and is preferably a water-soluble azo polymerization initiator such as 2, 2-azobis-2-methyl-N-2-hydroxyethylpropionamide. The polymerization temperature, time, etc. can be suitably selected.

The mass average molecular weight (Mw) of the acrylic resin is preferably 10000 to 200000 or so. More preferably 20000 to 150000. When Mw is 10000 or more, there is no fear of thermal decomposition in the tenter, and it is preferable. When Mw is 200000 or less, the viscosity of the coating liquid is not significantly increased, and the coatability is good.

As the binder of the easy-to-slide coating layer in the present invention, other binder resins may be used in combination in addition to the acrylic resin. Examples of the other binder resin include polyester resins, polyurethane resins, polyvinyl resins (such as polyvinyl alcohol), polyalkylene glycols, polyalkylene imines, methyl cellulose, hydroxy cellulose, and starches.

The content of the acrylic resin in the easy-slip coating layer is preferably 20 mass% or more and 95 mass% or less of the total solid content. More preferably 30% by mass or more and 90% by mass or less. When the amount is 20% by mass or more, the carboxyl group as the crosslinking component is not excessively decreased, and the crosslinking density is not lowered, so that it is preferable. If the content is 95% by mass or less, the amount of the crosslinking agent to be crosslinked is not excessively decreased, and the crosslinking density is not lowered, which is preferable.

(crosslinking agent)

In the present invention, in order to form a crosslinked structure in the slip-resistant coating layer, the slip-resistant coating layer preferably contains at least 1 crosslinking agent selected from an oxazoline crosslinking agent and a carbodiimide crosslinking agent. By containing an oxazoline-based crosslinking agent or a carbodiimide-based crosslinking agent, adhesion to a PET substrate is improved, crosslinking with a carboxyl group of an acrylic resin is promoted, and the strength of a coating film of an easy-slip layer can be improved. Further, other crosslinking agents may be used in combination, and specific examples of the crosslinking agent which can be used in combination include urea-based, epoxy-based, melamine-based, isocyanate-based, silanol-based, and the like. In addition, a catalyst or the like may be suitably used as necessary to promote the crosslinking reaction.

Examples of the crosslinking agent having an oxazoline group include: and oxazoline group-containing polymers obtained by copolymerizing oxazoline group-containing polymerizable unsaturated monomers with other polymerizable unsaturated monomers as needed by a conventionally known method (for example, solution polymerization, emulsion polymerization, etc.).

Examples of the polymerizable unsaturated monomer having an oxazoline include 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, 2-isopropenyl-4-methyl-2-oxazoline, and 2-isopropenyl-5-ethyl-2-oxazoline. These may be used alone, or 2 or more of them may be used in combination.

Examples of the other polymerizable unsaturated monomer include alkyl or cycloalkyl esters having 1 to 24 carbon atoms of (meth) acrylic acid such as methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, lauryl (meth) acrylate, isobornyl (meth) acrylate, and the like; hydroxyalkyl esters having 2 to 8 carbon atoms of (meth) acrylic acid such as 2-hydroxyethyl (meth) acrylate and hydroxypropyl (meth) acrylate; vinyl aromatic compounds such as styrene and vinyl toluene; adducts of (meth) acrylamide, dimethylaminopropyl (meth) acrylamide, dimethylaminoethyl (meth) acrylate, glycidyl (meth) acrylate and amines; polyethylene glycol (meth) acrylate; n-vinylpyrrolidone, ethylene, butadiene, chloroprene, vinyl propionate, vinyl acetate, (meth) acrylonitrile, and the like. These may be used alone, or 2 or more of them may be used in combination.

The other polymerizable unsaturated monomer is preferably a hydrophilic monomer from the viewpoint of using the obtained oxazoline group-containing crosslinking agent as a water-soluble crosslinking agent and improving compatibility with other resins, wettability, crosslinking reaction efficiency, and the like. Examples of the hydrophilic monomer include monomers having a polyethylene glycol chain such as 2-hydroxyethyl (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, monoester compounds of (meth) acrylic acid and polyethylene glycol, 2-aminoethyl (meth) acrylate and salts thereof, (meth) acrylamide, N-methylol (meth) acrylamide, N- (2-hydroxyethyl) (meth) acrylamide, (meth) acrylonitrile, and sodium styrenesulfonate. Among these, monomers having a polyethylene glycol chain, such as methoxypolyethylene glycol (meth) acrylate having high solubility in water, and monoester compounds of (meth) acrylic acid and polyethylene glycol, are preferable.

The content of oxazoline groups in the crosslinking agent having oxazoline groups is preferably 3.0 to 9.0 mmol/g. More preferably in the range of 4.0 to 8.0 mmol/g. A content of 4.0 to 8.0mmol/g is preferable because a proper crosslinked structure can be formed.

The carbodiimide-based crosslinking agent may include a monocarbodiimide compound and a polycarbodiimide compound, and the monocarbodiimide compound may include dicyclohexylcarbodiimide, diisopropylcarbodiimide, dimethylcarbodiimide, diisobutylcarbodiimide, dioctylcarbodiimide, t-butylisopropylcarbodiimide, diphenylcarbodiimide, di-t-butylcarbodiimide, di- β -naphthylcarbodiimide, and the like.

Examples of the diisocyanate which is a raw material for synthesizing the polycarbodiimide compound include isomers of toluene diisocyanate, aromatic diisocyanates such as 4, 4-diphenylmethane diisocyanate, aromatic aliphatic diisocyanates such as xylylene diisocyanate, alicyclic diisocyanates such as isophorone diisocyanate and 4, 4-dicyclohexylmethane diisocyanate, 1, 3-bis (isocyanotomethyl) cyclohexane, hexamethylene diisocyanate, and aliphatic diisocyanates such as 2,2, 4-trimethylhexamethylene diisocyanate. Aromatic aliphatic diisocyanates, alicyclic diisocyanates, and aliphatic diisocyanates are preferable for yellowing.

In addition, the diisocyanate may be used in such a manner that a compound which reacts with a terminal isocyanate such as a monoisocyanate is used to control the polymerization degree of the molecule to an appropriate degree. Examples of the monoisocyanate used for controlling the degree of polymerization of the polycarbodiimide by capping the ends of the polycarbodiimide include phenyl isocyanate, tolyl isocyanate, dimethylphenyl isocyanate, cyclohexyl isocyanate, butyl isocyanate, and naphthyl isocyanate. In addition, as the terminal capping agent, a compound having an OH group or-NH group may be used₂Radicals, COOH radicals, SO₃A compound of H group.

The condensation reaction accompanied by decarbonation of the diisocyanate is carried out in the presence of a carbodiimidization catalyst. Examples of the catalyst include phospholene oxides such as 1-phenyl-2-phospholene-1-oxide, 3-methyl-2-phospholene-1-oxide, 1-ethyl-2-phospholene-1-oxide, 3-methyl-1-phenyl-2-phospholene-1-oxide, and 3-phospholene isomers thereof, and 3-methyl-1-phenyl-2-phospholene-1-oxide is preferable from the viewpoint of reactivity. The amount of the catalyst used may be a catalytic amount.

The monocarbodiimide compound or the polycarbodiimide compound is preferably used in the form of an emulsion by emulsifying the compound with an appropriate emulsifier, since the monocarbodiimide compound or the polycarbodiimide compound is desirably kept in a uniformly dispersed state when being blended into the aqueous coating material; alternatively, a hydrophilic segment is added to the molecular structure of the polycarbodiimide compound and blended in the form of a self-emulsified product or a self-dissolved product in the coating material.

Examples of the carbodiimide-based crosslinking agent used in the present invention include water-dispersible and water-soluble crosslinking agents. The water-soluble resin is preferably water-soluble in view of good compatibility with other water-soluble resins and improvement in the crosslinking reaction efficiency of the easy-to-slip coating layer. In order to make the carbodiimide compound water-soluble, an isocyanate-terminated polycarbodiimide is synthesized by a condensation reaction accompanied by decarbonation of isocyanate, and then a hydrophilic site having a functional group reactive with an isocyanate group is further added, whereby the carbodiimide compound can be produced.

Examples of the hydrophilic site include: (1) quaternary ammonium salts of dialkylaminoalcohols, dialkylaminoalkylamines, and the like, (2) alkylsulfonates having at least 1 reactive hydroxyl group, and the like, (3) poly (ethylene oxide) capped with an alkoxy group, and mixtures of poly (ethylene oxide) and poly (propylene oxide), and the like. When the carbodiimide compound is introduced into the hydrophilic site, the carbodiimide compound is (1) cationic, (2) anionic, or (3) nonionic. Among them, nonionic resins which are compatible with the ionic properties of other water-soluble resins are preferable.

The content of the crosslinking agent in the easy-to-slip coating layer is preferably 5% by mass or more and 80% by mass or less of the total solid content. More preferably 10% by mass or more and 70% by mass or less. When the content is 5% by mass or more, the crosslinking density of the resin of the coating layer is not lowered, and therefore, it is preferable. If the content is 80% by mass or less, the amount of carboxyl groups in the acrylic resin to be crosslinked is not excessively reduced, and the crosslinking density is not lowered, which is preferable.

(particles in easy-slip coating layer)

The slip-resistant coating layer preferably contains lubricant particles for imparting slip properties to the surface. The particles may be inorganic particles or organic particles, and are not particularly limited, and include (1) inorganic particles such as silica, kaolinite, talc, light calcium carbonate, heavy calcium carbonate, zeolite, alumina, barium sulfate, carbon black, zinc oxide, zinc sulfate, zinc carbonate, zirconia, titania, satin white, aluminum silicate, diatomaceous earth, calcium silicate, aluminum hydroxide, halloysite, calcium carbonate, magnesium carbonate, calcium phosphate, magnesium hydroxide, and barium sulfate; (2) organic particles of acrylic or methacrylic, vinyl chloride, vinyl acetate, nylon, styrene/acrylic, styrene/butadiene, polystyrene/acrylic, polystyrene/isoprene, methyl methacrylate/butyl methacrylate, melamine, polycarbonate, urea, epoxy, urethane, phenol, diallyl phthalate, polyester, and the like, and silica is particularly preferably used in order to impart appropriate slidability to the coating layer.

The average particle diameter of the particles is preferably 10nm or more, more preferably 20nm or more, and further preferably 30nm or more. When the average particle diameter of the particles is 10nm or more, aggregation is less likely to occur, and the sliding property can be secured.

The average particle diameter of the particles is preferably 1000nm or less, more preferably 800nm or less, and still more preferably 600nm or less. When the average particle diameter of the particles is 1000nm or less, the transparency can be maintained and the particles are preferably not exfoliated.

For example, small particles having an average particle size of about 10 to 270nm and large particles having an average particle size of about 300 to 1000nm may be mixed to reduce the average width (RSm) of the contour elements while keeping the surface average roughness (Sa) of the region and the maximum protrusion height (P) described later, and it is preferable to use small particles having an average particle size of 30nm to 250nm in combination with large particles having an average particle size of 350 to 600nm in view of both the sliding property and the smoothness. When the small particles and the large particles are used in combination, the mass content of the small particles is preferably made larger than the mass content of the large particles in the entire solid content of the coating layer.

The average particle size of the particles was measured as follows: the particles of the cross section of the processed film were observed by a transmission electron microscope or a scanning electron microscope, and 100 particles which were not aggregated were observed, and the average value thereof was taken as the average particle diameter.

The shape of the particles is not particularly limited as long as the object of the present invention is satisfied, and spherical particles and irregular particles other than spherical particles can be used. The particle size of the amorphous particles can be calculated as the circle-equivalent diameter. The circle equivalent diameter is a value obtained by dividing the area of the observed particle by pi, calculating the square root, and doubling it.

The ratio of the particles to the total solid content of the slip-resistant coating layer is preferably 50% by mass or less, more preferably 40% by mass or less, and still more preferably 30% by mass or less. When the ratio of the particles to the entire solid content of the slip-coat layer is 50% by mass or less, the transparency can be maintained and the particles are not significantly peeled off from the slip-coat layer, and therefore, it is preferable.

The ratio of the particles to the total solid content of the slip-resistant coating layer is preferably 1 mass% or more, more preferably 1.5 mass% or more, and still more preferably 2 mass% or more. The ratio of the particles to the total solid content of the slip-resistant coating layer is preferably 1% by mass or more, since the slip property can be secured.

As a method for measuring the content of the particles contained in the easy-slip coating layer, for example, in the case of a resin containing an organic component and inorganic particles in the easy-slip coating layer, the following method can be employed. First, the easy-to-slide coating layer provided on the processed film is extracted from the processed film with a solvent or the like and dried to be solidified, thereby taking out the easy-to-slide coating layer. Next, heat is applied to the obtained easy-slip coating layer, and the organic component contained in the easy-slip coating layer is thermally burned and distilled off, whereby only the inorganic component can be obtained. The mass% of the particles contained in the easily slippery coating layer can be measured by measuring the weight of the obtained inorganic component and the easily slippery coating layer before removal by combustion distillation. In this case, a commercially available differential heat/thermogravimetric simultaneous measurement apparatus was used, and thus measurement was possible with high accuracy. When a plurality of types of particles are present, the ratio of the particles to the total solid content of the slip-resistant coating layer means the ratio of the total amount of the plurality of types of particles.

(additive in easy-slip coating layer)

In order to impart other functionality to the slip-coat layer, various additives may be contained within a range not impairing the coating appearance. Examples of the additives include fluorescent dyes, fluorescent brighteners, plasticizers, ultraviolet absorbers, pigment dispersants, foam inhibitors, defoaming agents, and preservatives.

The easy-slip coating layer may contain a surfactant for the purpose of improving leveling property at the time of coating and defoaming of the coating liquid. The surfactant may be any of cationic, anionic, nonionic, etc., and is preferably a silicone, acetylene glycol, or fluorine-based surfactant. These surfactants are preferably contained in the coating layer in a range in which the coating appearance is not abnormal by excessive addition.

As the coating method, any of a so-called inline coating method in which the polyester substrate film is simultaneously coated at the time of film formation and a so-called offline coating method in which the polyester substrate film is formed and then coated with a coater may be applied, and the inline coating method is effective, and more preferable.

As a coating method, any known method can be used for applying the coating liquid to a polyethylene terephthalate (hereinafter, sometimes abbreviated as PET) film. Examples thereof include a reverse roll coating method, a gravure coating method, a kiss coating method, a die coater method, a roll brush method, a spray coating method, an air knife coating method, a wire bar coating method, a tube blade method, an impregnation coating method, and a curtain coating method. These methods are used alone or in combination for coating.

In the present invention, as a method for providing an easy-slip coating layer on a polyester film, the following methods can be mentioned: a coating liquid containing a solvent, particles and a resin is applied to a polyester film and dried. Examples of the solvent include an organic solvent such as toluene, water, or a mixed system of water and a water-soluble organic solvent, and water alone or a so-called aqueous solvent in which a water-soluble organic solvent is mixed with water is preferable from the viewpoint of environmental problems.

The solid content concentration of the slip-facilitating coating liquid depends on the type of the binder resin, the type of the solvent, and the like, and is preferably 0.5% by mass or more, and more preferably 1% by mass or more. The solid content concentration of the coating liquid is preferably 35% by mass or less, more preferably 20% by mass or less.

The drying temperature after coating is preferably 70 ℃ or higher, and preferably 250 ℃ or lower, depending on the type of binder resin, the type of solvent, the presence or absence of a crosslinking agent, the solid content concentration, and the like.

(production of polyester film)

In the present invention, the polyester film to be the base film can be produced by a general method for producing a polyester film. For example, the following methods may be mentioned: a non-oriented polyester molded by melting and extruding a polyester resin into a sheet is stretched in the longitudinal direction at a temperature equal to or higher than the glass transition temperature by a speed difference between rolls, and then stretched in the transverse direction by a tenter to be subjected to heat treatment. Further, a method of simultaneously biaxially stretching the film in a longitudinal and transverse direction in a tenter may be mentioned.

In the present invention, the polyester film to be the base film may be a uniaxially stretched film or a biaxially stretched film, and a biaxially stretched film is preferable.

The thickness of the polyester film substrate is preferably 5 μm or more, more preferably 10 μm or more, and further preferably 15 μm or more. When the thickness is 5 μm or more, wrinkles are less likely to be formed when the film is conveyed, and it is preferable.

The thickness of the polyester film substrate is preferably 50 μm or less, more preferably 45 μm or less, and further preferably 40 μm or less. A thickness of 40 μm or less is preferable because the cost per unit area is reduced.

In the case of in-line coating, the coating may be applied to an unstretched film before stretching in the machine direction, or may be applied to a uniaxially stretched film before stretching in the transverse direction after stretching in the machine direction. In the case of coating before longitudinal stretching, a drying step is preferably provided before roll stretching. In the case of a uniaxially stretched film before transverse stretching, a drying step is compatible with a film heating step in a tenter, and therefore, a separate drying step is not necessarily required. The same applies to simultaneous biaxial stretching.

The thickness of the slip-resistant coating layer is preferably 0.001 μm or more, more preferably 0.01 μm or more, still more preferably 0.02 μm or more, and particularly preferably 0.03 μm or more. When the thickness of the coating layer is 0.001 μm or more, the film-forming property of the coating film can be maintained, and a uniform coating film can be obtained, which is preferable.

The thickness of the slip-resistant coating layer is preferably 2 μm or less, more preferably 1 μm or less, still more preferably 0.8 μm or less, and particularly preferably 0.5 μm or less. When the film thickness of the coating layer is 2 μm or less, blocking is not liable to occur, and it is preferable.

The ceramic green sheet coated and formed on a release coating layer described later is coated and formed, and then wound up in a roll shape together with a release film. At this time, the easily-slippery coating layer of the release film was taken up in contact with the surface of the ceramic green sheet. In order to prevent the occurrence of defects on the surface of the ceramic green sheet, the outer surface of the easy-to-slide coating layer (the surface of the easy-to-slide coating layer of the entire coating film not in contact with the polyester film) needs to be appropriately flat, and preferably, the areal surface average roughness (Sa) is 1nm to 25nm, and the maximum protrusion height (P) is 60nm to 500 nm.

When the regional surface average roughness (Sa) of the outer surface of the easy-to-slide coating layer is 1nm or more and the maximum protrusion height (P) is 60nm or more, the easy-to-slide coating surface is not excessively smooth and appropriate sliding properties can be maintained, which is preferable. When the area surface average roughness (Sa) is 25nm or less and the maximum protrusion height (P) is 500nm or less, the easily-coated surface is not excessively roughened, and defects of the ceramic green sheet due to protrusions are not generated, which is preferable.

In the present invention, it is preferable that the average width (RSm) of the contour elements is 10 μm or less, in addition to the region surface average roughness (Sa) and the maximum protrusion height (P) being in the above ranges. By controlling the average width (RSm) of the contour elements to 10 μm or less, the number of protrusions per unit area increases. If the number of projections is increased, the pressure applied to each projection is dispersed and reduced, and therefore, the occurrence of pinholes can be effectively suppressed. The average width (RSm) of the outline elements is more preferably 5 μm or less, and still more preferably 3 μm or less. However, since the average width (RSm) of the contour elements is too small, which is associated with an excessive content of particles in the slip-prone coating layer, and the area surface average roughness (Sa) is large, and the maximum protrusion height (P) is large, it is preferably 0.1 μm or more, and may be 0.5 μm or more, or may be 1 μm or more.

In the present invention, the average particle diameter of the particles contained in the easy-slip coating layer is preferably 1000nm or less so that the average width (RSm) of the contour elements is within a predetermined range. More preferably 800nm or less, and still more preferably 600nm or less. When the particle size is 1000nm or less, the distance between particles is not excessively increased, and it is preferable to adjust RSm to a predetermined range.

(mold release coating layer)

The resin constituting the release coating layer in the present invention is not particularly limited, and a silicone resin, a fluororesin, an alkyd resin, various waxes, an aliphatic olefin, and the like can be used, and each resin can be used alone or in combination of 2 or more.

In the present invention, the release coating layer is, for example, a silicone resin which has a silicone structure in the molecule, and examples thereof include a curable silicone, a silicone graft resin, a modified silicone resin such as an alkyl modification, and the like, and from the viewpoint of migration, a reactive cured silicone resin is preferably used. As the reactive curable silicone resin, addition reaction type, condensation reaction type, ultraviolet or electron beam curing type, and the like can be used. More preferably, the curable resin composition may be an addition reaction system curable at low temperature and capable of being processed at low temperature, or an ultraviolet or electron beam curing system. By using these, the polyester film can be processed at a low temperature in coating processing. Therefore, a polyester film having high flatness and little thermal damage to the polyester film during processing can be obtained, and defects such as pinholes can be reduced when producing an ultrathin ceramic green sheet having a thickness of 0.2 to 2.0 μm.

Examples of the addition reaction type silicone resin include: and a platinum catalyst, wherein polydimethylsiloxane having a vinyl group introduced at a terminal or a side chain thereof and hydrogen siloxane are reacted with each other and cured. In this case, it is more preferable that the resin which can be cured at 120 ℃ for 30 seconds or less is used, since the processing can be performed at a low temperature. Examples thereof include low temperature addition curing type (LTC1006L, LTC1056L, LTC300B, LTC303E, LTC310, LTC314, LTC350G, LTC450A, LTC371G, LTC750A, LTC755, LTC760A, etc.) and thermal UV curing type (LTC851, BY24-510, BY24-561, BY24-562, etc.), solvent addition + UV curing type (X62-5040, X62-5065, X62-5072T, KS5508, etc.) and Dual cure type (X62-2835, X62-2834, X62-1980, etc.) manufactured BY Dow Corning Toray.

Examples of the silicone resin of the condensation reaction system include: a three-dimensional crosslinked structure is produced by condensation reaction of a polydimethylsiloxane having an OH group at the terminal and a polydimethylsiloxane having an H group at the terminal using an organotin catalyst.

Examples of the ultraviolet-curable silicone resin include: the most basic type is one obtained by the same radical reaction as in the crosslinking of a general silicone rubber; introducing unsaturated groups and photocuring the resulting product; decomposing an onium salt under ultraviolet rays to generate a strong acid, thereby cleaving and crosslinking an epoxy group; crosslinking the resulting product by an addition reaction of mercapto groups to vinylsiloxanes; and the like. In addition, electron beams may be used instead of the ultraviolet rays. Electron beams are more energetic than ultraviolet rays, and can undergo a crosslinking reaction by radicals without using an initiator as in the case of ultraviolet ray curing. Examples of the resin to be used include UV-curable silicones available from shin-Etsu chemical Co., Ltd (X62-7028A/B, X62-7052, X62-7205, X62-7622, X62-7629, X62-7660, etc.), UV-curable silicones available from MomentivePerformance Materials, Inc. (TPR6502, TPR6501, TPR6500, UV9300, UV9315, XS56-A2982, UV9430, etc.), and UV-curable silicones available from Silicolas UV POLY200, POLY215, POLY201, KF-UV265AM, etc.).

As the ultraviolet-curable silicone resin, there may be used: acrylate-modified and glycidoxy-modified polydimethylsiloxanes, and the like. These modified polydimethylsiloxanes are mixed with a polyfunctional acrylate resin, an epoxy resin or the like, and used in the presence of an initiator, whereby good mold release properties can be exhibited.

Examples of the resin to be used in addition to the above-mentioned epoxy resin include alkyd resins such as stearyl-modified and lauryl-modified alkyd resins, acrylic resins, alkyd resins obtained by reaction of methylated melamine, and acrylic resins.

Examples of the aminoalkyd resin obtained by the reaction of the methylated melamine include Tesfine303, Tesfine305, Tesfine314 manufactured by hitachi chemical co. Examples of the amino acrylic resin obtained by the reaction of methylated melamine include Tesfine322 available from Hitachi chemical Co.

When the above-mentioned resin is used for the release coating layer in the present invention, 1 kind may be used, or 2 or more kinds may be mixed and used. In addition, additives such as light release additives and heavy release additives may be mixed in order to adjust the release force.

The release coating layer in the present invention may contain particles having a particle diameter of 1 μm or less, and preferably does not substantially contain a substance forming protrusions such as particles from the viewpoint of pinhole generation.

In the present invention, additives such as adhesion improving agents and antistatic agents may be added to the release coating layer. In order to improve adhesion to the substrate, it is also preferable to perform pretreatment such as anchor coating, corona treatment, plasma treatment, and atmospheric pressure plasma treatment on the surface of the polyester film before providing the release coating layer.

In the present invention, the thickness of the release coating layer is not particularly limited and may be set according to the purpose of use, but the thickness of the release coating layer after curing is preferably in the range of 0.005 to 2.0 μm. The thickness of the release coating layer is preferably 0.005 μm or more because the release performance can be maintained. Further, if the thickness of the release coating layer is 2.0 μm or less, the curing time is not excessively increased, and variation in the thickness of the ceramic green sheet due to reduction in the planarity of the release film is not concerned, which is preferable. Further, since the curing time is not excessively long, there is no fear that the resin constituting the release coating layer is aggregated and there is no fear that a projection is formed, and therefore, the defect of pin holes of the ceramic green sheet is not easily generated, which is preferable.

The outer surface of the film on which the release coating layer is formed (the surface of the release coating layer of the entire coated film which is not in contact with the polyester film) is desirably flat so as not to cause defects in the ceramic green sheet coated and molded thereon, and the area surface average roughness (Sa) is preferably 5nm or less and the maximum protrusion height (P) is preferably 30nm or less. More preferably, the area surface average roughness is 5nm or less and the maximum protrusion height is 20nm or less. When the area surface roughness is 5nm or less and the maximum protrusion height is 30nm or less, no defective spots such as pinholes are generated during the formation of the ceramic green sheet, and the yield is good. The smaller the area surface average roughness (Sa) is, the more preferable it is, it may be 0.1nm or more, and may be 0.3nm or more. The smaller the maximum protrusion height (P) is, the more preferable, the maximum protrusion height may be 1nm or more, or may be 3nm or more.

In the present invention, in order to adjust the surface of the film on which the release coating layer is formed to have a predetermined roughness range, it is preferable that the PET film contains substantially no inorganic particles. In the present invention, the phrase "substantially not containing inorganic particles" means that both the base film and the release coating layer are defined as being 50ppm or less, preferably 10ppm or less, and most preferably the detection limit or less, when the particle-derived elements are quantitatively analyzed by fluorescent X-ray analysis. This is because, even if the particles are not positively added to the base film, a contaminant component derived from foreign matter or a contaminant adhering to a production line or an apparatus in a production process of the raw resin or the film may be peeled off and mixed into the film.

In the present invention, the method for forming the release coating layer is not particularly limited, and the following methods can be used: a coating liquid in which a mold-release resin is dissolved or dispersed is spread on one surface of a polyester film of a substrate by coating or the like, and after removing a solvent or the like by drying, the polyester film is dried by heating, cured by heat, or cured by ultraviolet rays. In this case, the drying temperature at the time of solvent drying and heat curing is preferably 180 ℃ or lower, more preferably 150 ℃ or lower, and most preferably 120 ℃ or lower. The heating time is preferably 30 seconds or less, more preferably 20 seconds or less. When the temperature is 180 ℃ or lower, the flatness of the film can be maintained, and the possibility of causing thickness unevenness of the ceramic green sheet is small, and it is preferable. If the temperature is 120 ℃ or lower, the processing can be carried out without impairing the planarity of the film, and the possibility of causing thickness unevenness of the ceramic green sheet is further reduced, which is particularly preferable.

In the present invention, the surface tension of the coating liquid when applying the release coating layer is not particularly limited, but is preferably 30mN/m or less. By setting the surface tension to the above, the coatability after coating is improved, and unevenness on the surface of the coating film after drying can be reduced.

In the present invention, the coating liquid used for applying the release coating layer is not particularly limited, and a solvent having a boiling point of 90 ℃ or higher is preferably added. By adding a solvent having a boiling point of 90 ℃ or higher, bumping during drying can be prevented, the coating film can be leveled, and the smoothness of the surface of the coating film after drying can be improved. The amount of the additive is preferably about 10 to 80% by mass based on the whole coating liquid.

As the coating method of the coating liquid, any known coating method can be applied, and for example, conventionally known methods such as a roll coating method such as a gravure coating method and a reverse coating method, a bar coating method such as a wire bar, a die coating method, a spray coating method, and an air knife coating method can be used.

(ceramic Green sheet and ceramic capacitor)

Generally, a laminated ceramic capacitor has a ceramic body in a rectangular parallelepiped shape. In the interior of the ceramic body, the 1 st internal electrode and the 2 nd internal electrode are alternately provided in the thickness direction. The 1 st internal electrode is exposed at the 1 st end surface of the ceramic body. A1 st external electrode is provided on the 1 st end face. The 1 st internal electrode is electrically connected to the 1 st external electrode at the 1 st end face. The 2 nd internal electrode is exposed at the 2 nd end surface of the ceramic body. A2 nd external electrode is provided on the 2 nd end face. The 2 nd internal electrode is electrically connected to the 2 nd external electrode at the 2 nd end face.

The release film for producing a ceramic green sheet of the present invention is used for producing such a laminated ceramic capacitor. For example, it can be produced as follows. First, a ceramic slurry for forming a ceramic body is applied and dried using the release film of the present invention as a carrier film. On the ceramic green sheet after coating and drying, a conductive layer for constituting the 1 st or 2 nd internal electrode was printed. The ceramic green sheets, the ceramic green sheets on which the conductive layers for constituting the 1 st internal electrode are printed, and the ceramic green sheets on which the conductive layers for constituting the 2 nd internal electrode are printed are stacked as appropriate and pressed to obtain a mother laminate. The mother laminate is cut into a plurality of pieces to produce an original ceramic body. The ceramic body is obtained by firing the original ceramic body. After that, the 1 st and 2 nd external electrodes are formed, whereby a laminated ceramic capacitor can be completed.

Examples

The present invention will be described in detail with reference to examples and comparative examples, but it is needless to say that the present invention is not limited to the following examples. The evaluation method used in the present invention is as follows.

[ NMR measurement ]

The ratio of the copolymerization component introduced into the acrylic polyol was measured by nuclear magnetic resonance spectroscopy (¹H-NMR、¹³C-NMR: varian Unity 400, manufactured by Agilent) was confirmed. The assay was performed as follows: the solvent in the synthesized acrylic polyol was removed in a vacuum dryer, and then the dried product was dissolved in deuterated chloroform. The peaks of chemical shifts δ (ppm) ascribed to the sites of the respective groups were identified from the obtained NMR spectra. The integrated intensity of each peak obtained was obtained, and the composition ratio (mol%) of the copolymerization component introduced into the acrylic polyol was confirmed from the number of hydrogens at the site of each group and the integrated intensity.

[ confirmation of Tg ]

The Tg of each acrylic polyol was determined from the compositional ratio of the copolymerized components determined by the NMR measurement and the Fox formula.

[ stretching Adaptation ]

In order to evaluate the stretchability of the acrylic polyol itself, the synthesized acrylic polyols (1) to (12) were put into a mixed solvent (25 ℃) of 30 mass% isopropyl alcohol and 70 mass% water so that the solid content concentration became 12 mass%, and a solution of the acrylic polyol alone was prepared, and then the solution was applied to the surface of a polyester film subjected to only longitudinal stretching using a wire bar # 5. Subsequently, the film sample on which the coating layer (thickness: 6.5 μm) was formed was left to stand in a hot air circulating oven set at 60 ℃ for 30 seconds, and then the film sample was taken out from the oven and subjected to preliminary drying. Subsequently, the sample was prepared, mounted on a stretching apparatus (manufactured by Toyobo Engineering Company), and placed in a hot air circulating oven at 100 ℃ to be slowly stretched. The stretching operation was performed until the length was 4 times the length before stretching, and the stretching apparatus was taken out of the hot air circulating oven. Then, the stretched coating film was observed with an optical microscope (magnification: 200 times), and the presence or absence of cracks generated by stretching was determined according to the following criteria.

○ No cracks were observed at all.

△ slight cracks (1 to 4) were visible.

X: 5 or more cracks, or cracks visible in the entire surface.

(1) Surface characteristics of coating film

The values obtained were measured under the following conditions using a non-contact surface shape measuring system (VertScan R550H-M100). The area surface average roughness (Sa) and the average width of the contour elements (RSm) were the average of 5 measurements, and the maximum protrusion height (P) was the maximum of 5 measurements.

(measurement conditions)

Measurement mode: WAVE mode

Objective lens: 50 times of

0.5 × Tube lens

Measurement area 187X 139. mu.m (measurement of Sa and P)

Measurement length (Lr: reference length): 187 μm (RSm measurement)

(2) Evaluation of particle dispersibility of easy-to-slide coating layer

The maximum protrusion height (P) measured in (1) above is used for the determination according to the following criteria.

○ maximum protrusion height (P) is 0.2 μm or less

○△ maximum bump height (P) is greater than 0.2 μm and less than 0.3 μm.

△ maximum protrusion height (P) of 0.3 μm or more

(3) Measurement of Marek's hardness and elastic deformation Power of resin/crosslinking agent mixture composition Single film of easily slidable coating layer

The resin/crosslinking agent mixture composition as a sample was adjusted with a mixed solvent (25 ℃) of 30 mass% isopropyl alcohol and 70 mass% water so that the solid content concentration became 12 mass%. The solution was applied to the surface of the slide glass with a bar # 28. Subsequently, the slide glass sample on which the coating layer (thickness 5.0 μm) was formed was left to stand in a hot air circulating oven set at 80 ℃ for 5 minutes, and then the film sample was taken out from the oven to be subjected to preliminary drying. Next, the sample was left to stand in a hot air circulating oven set at 230 ℃ for 2 minutes, and then the film sample was taken out from the oven to be subjected to heat treatment.

The surface of the obtained sample piece was subjected to a load-unload test using a dynamic ultramicro hardness tester (DUH-211S, manufactured by shimadzu corporation) and from this measurement, the mahalanobis Hardness (HM) and the elastic deformation power (η it) (n is an average value of 10) were obtained using the following formulas.

HM＝F/(26.43×h²)(N/mm²)

(F: load (N), h: depth of indentation (mm))

Wtotal＝Wplast+Welast(N·m)

(Wtotal ═ total deformation work (N · m), Wplast ═ plastic deformation work (N · m), Welast ═ elastic deformation work (N · m))

ηit＝(Welast/Wplast)×100(％)

(measurement conditions)

(1) Using a pressure head: diamond regular and triangular pyramid indenter (inter-edge angle 115 degree)

(2) Measurement mode: load-unload test

(3) Test force: 0.5mN

(4) Minimum test force: 0.002mN

(5) Load speed: 0.025mN/sec

(6) Load retention time: 2sec

(7) Unloading and maintaining time: 0sec

(8) And (3) measuring atmosphere: 25 +/-1 ℃ and 65 +/-5% RH

(9) And (3) measuring n number: 10

(4) Unwinding electrification of release film roll

The release films for green sheet production obtained in each example and each comparative example were rolled up into a roll shape having a width of 400mm and a length of 5000m to obtain a release film roll. The release film roll was stored at 40 ℃ and a humidity of 50% or less for 30 days, and then the charge amount at the time of unwinding at 100 m/min was measured by "KSD-0103" manufactured by spring Motor Co. The charge amount was as follows: the portion of 100mm immediately after unwinding was measured at an unwinding length of 500M, and the average value thereof was calculated.

○ less than +/-3 kV

○△ +/-3 kV or more and less than 5kV

△ +/-5 kV or more and less than 10kV

X: over +/-10 kV

(5) Evaluation of pinhole and thickness unevenness of ceramic Green sheet

A composition comprising the following materials was stirred and mixed, and dispersed for 2 hours with a paint shaker using 2.0mm glass beads as a dispersion medium to obtain a ceramic slurry.

(hydropsy chemical industry Co., Ltd., S-LEC BH-3)

Next, the release surface of the release film sample was coated with an applicator so that the dried slurry had a thickness of 0.5 μm, dried at 90 ℃ for 1 minute, and then the slurry surface and the smooth coating layer surface were superposed on each other and applied at 1kg/cm²After 10 minutes of the load, the release film was peeled off to obtain a ceramicGreen sheet.

In the central region of the obtained ceramic green sheet in the film width direction, 25cm²In the above range, the surface of the ceramic slurry opposite to the coated surface was irradiated with light, and the occurrence of pinholes visible through light transmission was observed, and the occurrence was visually evaluated according to the following criteria.

○ No pinhole, no thickness unevenness

△ slight pinholes occurred and slight thickness unevenness was observed.

X: a small number of pinholes occurred, and the thickness unevenness was slightly noticeable.

(preparation of polyethylene terephthalate Pellets (PET) (I))

As the esterification reaction apparatus, a continuous esterification reaction apparatus comprising a 3-stage complete mixing tank having a stirring apparatus, a partial condenser, a raw material inlet and a product outlet was used. TPA (terephthalic acid) was adjusted to 2 ton/hr, EG (ethylene glycol) was adjusted to 2 mol based on TPA1 mol, and antimony trioxide was adjusted to 160ppm based on atoms of PET and Sb produced, and these slurries were continuously supplied to the 1 st esterification reaction vessel of the esterification reaction apparatus, and reacted at 255 ℃ with an average residence time of 4 hours under normal pressure. Then, the reaction product in the 1 st esterification reaction vessel was continuously taken out of the system, supplied to the 2 nd esterification reaction vessel, and 8 mass% of EG distilled off from the 1 st esterification reaction vessel was supplied to the 2 nd esterification reaction vessel, and further, an EG solution containing magnesium acetate tetrahydrate salt in an amount of 65ppm in terms of Mg atom to the produced PET and an EG solution containing TMPA (trimethyl phosphate) in an amount of 40ppm in terms of P atom to the produced PET were added thereto, and the mixture was reacted at an average residence time of 1 hour and 260 ℃. Then, the reaction product in the 2 nd esterification reaction vessel was continuously taken out of the system, supplied to the 3 rd esterification reaction vessel, and kept at 39MPa (400 kg/cm) by using a high-pressure disperser (manufactured by Nippon Seiko Co., Ltd.)²) 0.2 mass% of porous colloidal silica having an average particle diameter of 0.9 μm which had been subjected to dispersion treatment 5 times in average, and 0.6 μm in average particle diameter of ammonium salt to which polyacrylic acid was attached in an amount of 1 mass% per unit of calcium carbonate0.4 mass% of calcium was added as 10% EG slurry, and the mixture was reacted at 260 ℃ for 0.5 hour at an average retention time under normal pressure. The esterification reaction product produced in the 3 rd esterification reaction vessel was continuously supplied to a 3-stage continuous polycondensation reaction apparatus, subjected to polycondensation, filtered with a filter obtained by sintering 95% stainless steel fibers having a cutoff diameter of 20 μm, ultrafiltered and extruded into water, cooled and cut into small pieces to obtain PET chips (hereinafter, abbreviated as PET (i)) having an intrinsic viscosity of 0.60 dl/g. The content of the lubricant in the PET chips was 0.6 mass%.

(preparation of polyethylene terephthalate Pellets (PET) (II))

On the other hand, in the production of the above PET chips, PET chips having an intrinsic viscosity of 0.62dl/g (hereinafter, abbreviated as PET (II)) completely free of particles such as calcium carbonate and silica are obtained.

(production of laminated film Z)

These PET chips were dried, melted at 285 ℃ and melted by different melt extruders at 290 ℃ to: a filter obtained by sintering stainless steel fibers having a 95% cutoff diameter of 15 μm and a filter obtained by sintering stainless steel particles having a 95% cutoff diameter of 15 μm were subjected to 2-stage filtration, and the resulting filtrate was combined in a feed block, laminated so that PET (I) became a reverse mold release surface side layer and PET (II) became a mold release surface side layer, extruded (cast) into a sheet form at a speed of 45 m/min, and subjected to electrostatic adhesion and cooling on a casting drum at 30 ℃ by an electrostatic adhesion method to obtain an unstretched polyethylene terephthalate sheet having an intrinsic viscosity of 0.59 dl/g. The layer ratio was adjusted so that the discharge amount of each extruder was 60%/40% of pet (i)/(II). Subsequently, the unstretched sheet was heated by an infrared heater and then stretched 3.5 times in the machine direction at a roll temperature of 80 ℃ by a speed difference between rolls. Thereafter, the resultant was introduced into a tenter and stretched at 140 ℃ by 4.2 times in the transverse direction. Next, in the heat fixing zone, heat treatment was performed at 210 ℃. Thereafter, relaxation treatment was carried out at 170 ℃ for 2.3% in the transverse direction to obtain a biaxially stretched polyethylene terephthalate film Z having a thickness of 31 μm. The Sa of the release side layer of the obtained film Z was 2nm, and the Sa of the reverse release side layer was 28 nm.

(production of acrylic polyol A-1)

Into a four-necked flask equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen gas blowing tube, 77 parts by mass of Methyl Methacrylate (MMA), 100 parts by mass of hydroxyethyl methacrylate (HEMA), 33 parts by mass of methacrylic acid (MAA) and 490 parts by mass of isopropyl alcohol (IPA) were charged, and the temperature in the flask was raised to 80 ℃ while stirring. After stirring the flask at 80 ℃ for 3 hours, 0.5 part by mass of 2, 2-azobis-2-methyl-N-2-hydroxyethylpropionamide was added to the flask. After the flask was purged with nitrogen while the temperature was raised to 120 ℃, the mixture was stirred at 120 ℃ for 2 hours.

Subsequently, the unreacted raw material and the solvent were removed by reducing the pressure at 120 ℃ under 1.5kPa to obtain an acrylic polyol. The pressure in the flask was returned to atmospheric pressure, the flask was cooled to room temperature, and 840 parts by mass of a mixed IPA aqueous solution (water content 50 mass%) was added. Then, while stirring, triethylamine was added through a dropping funnel, and neutralization treatment of the acrylic polyol was performed until the pH of the solution became 5.5 to 7.5, thereby obtaining acrylic polyol (a-1) having a solid content concentration of 20 mass%. The composition ratio, Tg, elongation property and acid value of the acrylic polyol (A-1) measured by NMR are shown in Table 1.

(production of acrylic polyols (A-2) to (A-12))

Acrylic polyols (A-2) to (A-12) having a solid content concentration of 20 mass% were obtained in the same manner as in the production of acrylic polyol 1, except that the amounts of MMA, St, SMA, HEMA, MAA, AA, IPA at the time of charging and IPA aqueous solution at the time of dilution were changed as shown in Table 1. The composition ratios, Tg, elongation properties, and acid values of the acrylic polyols (A-2) to (A-12) measured by NMR are shown in Table 1. The composition ratios are as follows: MMA, St (styrene), and SMA (stearyl methacrylate) are represented by l-1, l-2, and l-3 (units), respectively, HEMA is represented by m (unit), and MAA and AA (acrylic acid) are represented by n (unit).

[ Table 1]

(polymerization of polyester resin B0-1)

194.2 parts by mass of dimethyl terephthalate, 184.5 parts by mass of dimethyl isophthalate, 14.8 parts by mass of dimethyl isophthalate-5-sulfonic acid sodium salt, 185.1 parts by mass of ethylene glycol, 185.1 parts by mass of neopentyl glycol, and 0.2 part by mass of tetra-n-butyl titanate were put into a stainless autoclave equipped with a stirrer, a thermometer, and a partial reflux condenser, and ester exchange reaction was carried out at a temperature of 160 to 220 ℃ for 4 hours. Subsequently, the temperature was raised to 255 ℃ and the pressure of the reaction system was gradually reduced, followed by reaction under a reduced pressure of 30Pa for 1 hour and 30 minutes to obtain a copolyester resin (B0-1). The resulting copolyester resin (B0-1) was transparent in pale yellow. The reduced viscosity of the copolyester resin (B0-1) was measured to find that it was 0.60 dl/g. The glass transition temperature based on DSC is 65 ℃.

(production of aqueous polyester Dispersion B-1)

In a reactor equipped with a stirrer, a thermometer and a reflux apparatus, 30 parts by mass of a polyester resin (B0-1) and 15 parts by mass of ethylene glycol-n-butyl ether were placed, and the mixture was heated and stirred at 110 ℃ to dissolve the resin. After the resin was completely dissolved, 55 parts by mass of water was slowly added to the polyester solution while stirring. After the addition, the liquid was cooled to room temperature while stirring, to prepare a milky-white aqueous polyester dispersion (B-1) having a solid content of 30 mass%.

(polymerization of polyester resin B0-2)

163 parts by mass of dimethyl terephthalate, 163 parts by mass of dimethyl isophthalate, 169 parts by mass of 1, 4-butanediol, 324 parts by mass of ethylene glycol, and 0.5 part by mass of tetra-n-butyl titanate were charged into a stainless autoclave equipped with a stirrer, a thermometer, and a partial reflux condenser, and ester exchange reaction was carried out at 160 ℃ to 220 ℃ for 4 hours.

Then, 14 parts by mass of fumaric acid and 203 parts by mass of sebacic acid were added, and the temperature was raised from 200 ℃ to 220 ℃ over 1 hour to perform an esterification reaction. Subsequently, the temperature was raised to 255 ℃ and the pressure of the reaction system was gradually reduced, followed by reaction under a reduced pressure of 29Pa for 1 hour and 30 minutes to obtain a hydrophobic copolyester resin (B0-2). The resulting hydrophobic copolyester resin (B0-2) was transparent in pale yellow.

(production of aqueous polyester Dispersion B-2)

Then, 60 parts by mass of the copolyester resin (B0-2), 45 parts by mass of methyl ethyl ketone and 15 parts by mass of isopropyl alcohol were placed in a reactor equipped with a stirrer, a thermometer, a reflux device and a quantitative dropping device for producing a graft resin, and the resin was dissolved by heating and stirring at 65 ℃. After the resin was completely dissolved, 24 parts by mass of maleic anhydride was added to the polyester solution.

Subsequently, a solution prepared by dissolving 16 parts by mass of styrene and 1.5 parts by mass of azobisdimethylvaleronitrile in 19 parts by mass of methyl ethyl ketone was added dropwise to the polyester solution at a rate of 0.1 ml/min, and the mixture was stirred for a further 2 hours. After sampling for analysis from the reaction solution, 8 parts by mass of methanol was added. Subsequently, 300 parts by mass of water and 24 parts by mass of triethylamine were added to the reaction solution, and stirred for 1 hour.

Then, the internal temperature of the reactor was increased to 100 ℃ and methyl ethyl ketone, isopropyl alcohol and excess triethylamine were distilled off by distillation to obtain a pale yellow transparent polyester resin, and a uniform water-dispersible polyester graft copolymer dispersion (B-2) having a solid content of 25 mass% was prepared. The glass transition temperature of the resulting polyester-based graft copolymer was 68 ℃.

(aqueous polyester dispersion B-3)

Toyo spin, Vylonal (registered trademark) MD1500 (Tg: 77 ℃ C., solid content concentration 30 mass%) was used.

(production of aqueous polyurethane Dispersion C-1)

In a four-necked flask equipped with a stirrer, a serpentine condenser, a nitrogen introduction tube, a silica gel drying tube, and a thermometer, 43.75 parts by mass of 4, 4-dicyclohexylmethane diisocyanate, 12.85 parts by mass of dimethylolbutyric acid, 153.41 parts by mass of polyhexamethylene carbonate diol having a number average molecular weight of 2000, 0.03 parts by mass of dibutyltin dilaurate, and 84.00 parts by mass of acetone as a solvent were charged, and the mixture was stirred at 75 ℃ for 3 hours under a nitrogen atmosphere, whereby it was confirmed that the reaction solution had a predetermined amine equivalent. Then, the process of the present invention is carried out,after the reaction solution was cooled to 40 ℃, 8.77 parts by mass of triethylamine was added to obtain a polyurethane prepolymer solution. Next, 450g of water was added to a reaction vessel equipped with a homogeneous disperser capable of high-speed stirring, and the temperature was adjusted to 25 ℃ for 2000min^-1The polyurethane prepolymer solution was added to the mixture while stirring and mixing the mixture, and the mixture was dispersed in water. Then, under reduced pressure, acetone and water were partially removed to prepare a water-soluble urethane resin solution C-1 having a solid content of 37 mass%. The glass transition temperature of the obtained polyurethane resin was-30 ℃.

(preparation of oxazoline-based crosslinking agent D-1)

In a flask equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, and a thermometer, 460.6 parts of isopropyl alcohol were charged, and the flask was heated to 80 ℃ while nitrogen gas was slowly flowed. To this were added dropwise over 2 hours from a dropping funnel a monomer mixture containing 126 parts of methyl methacrylate, 210 parts of 2-isopropenyl-2-oxazoline and 84 parts of methoxypolyethylene glycol acrylate prepared in advance and an initiator solution containing 21 parts of 2, 2' -azobis (2-methylbutyronitrile) (Nippon Hydrazine Industry co., ltd., "ABN-E" manufactured by ltd.) and 189 parts of isopropyl alcohol as a polymerization initiator, respectively, and allowed to react, followed by further reaction for 5 hours after the completion of the addition. During the reaction, nitrogen gas was continuously passed through the flask, and the temperature in the flask was maintained at 80. + -. 1 ℃. Thereafter, the reaction solution was cooled to obtain an oxazoline group-containing resin (D-1) having a solid content of 25%. The oxazoline group content of the resulting oxazoline group-having resin (D-1) was 4.3mmol/g, and the number average molecular weight thereof was 20000 as measured by GPC (gel permeation chromatography).

(preparation of oxazoline-based crosslinking agent D-2)

The oxazoline group-containing resin (D-2) having a solid content concentration of 10% and having a different composition (oxazoline group weight and molecular weight) was obtained in the same manner as in the synthesis of the oxazoline group-containing resin (D-1). The oxazoline group-containing resin (D-2) thus obtained had an oxazoline group content of 7.7mmol/g and a number average molecular weight of 40000 as measured by GPC.

(production of carbodiimide crosslinking agent E-1)

168 parts by mass of hexamethylene diisocyanate and 220 parts by mass of polyethylene glycol monomethyl ether (M400, average molecular weight 400) were put into a flask equipped with a stirrer, a thermometer and a reflux condenser, and stirred at 120 ℃ for 1 hour, and 26 parts by mass of 4, 4' -dicyclohexylmethane diisocyanate and 3.8 parts by mass of 3-methyl-1-phenyl-2-phospholene-1-oxide (2% by mass relative to the total isocyanate) as a carbodiimidization catalyst were further added thereto, and further stirred under a nitrogen stream at 185 ℃ for 5 hours. The infrared spectrum of the reaction solution was measured, and the wavelength was found to be 2200 to 2300cm^-1The absorption of (2) disappears. Naturally cooled to 60 ℃ and added with 567 parts by mass of ion-exchanged water to obtain a carbodiimide water-soluble resin (E-1) having a solid content of 40 mass%.

(production of isocyanate crosslinking agent F-1)

100 parts by mass of a polyisocyanate compound having an isocyanurate structure (manufactured by Asahi Kasei Chemicals Corp., DuranateTPA), 55 parts by mass of propylene glycol monomethyl ether acetate, and 30 parts by mass of polyethylene glycol monomethyl ether (average molecular weight 750) each of which was prepared from hexamethylene diisocyanate were put into a flask equipped with a stirrer, a thermometer, and a reflux condenser, and the flask was held at 70 ℃ for 4 hours under a nitrogen atmosphere. Thereafter, the temperature of the reaction solution was lowered to 50 ℃ and 47 parts by mass of methyl ethyl ketoxime was added dropwise. The infrared spectrum of the reaction mixture was measured, and it was confirmed that the absorption of isocyanate groups had disappeared, whereby an aqueous dispersion of a blocked polyisocyanate (F-1) having a solid content of 75 mass% was obtained.

(silica particles G-1)

Colloidal silica (trade name MP2040, average particle diameter 200nm, solid content concentration 40% by mass, manufactured by Nissan chemical Co., Ltd.)

(silica particles G-2)

Colloidal silica (trade name SNOWTEX XL manufactured by Nissan chemical Co., Ltd., average particle diameter 40nm, solid content concentration 40% by mass)

(silica particles G-3)

Colloidal silica (trade name SNOWTEX ZL, manufactured by Nissan Chemicals, average particle diameter 100nm, solid content concentration 40% by mass)

(silica particles G-4)

Colloidal silica (trade name MP4540M, manufactured by Nissan chemical Co., Ltd., average particle diameter 450nm, solid content concentration 40% by mass)

(acrylic particles G-5)

Acrylic particle aqueous dispersion (trade name MX100W, manufactured by Japan catalyst, average particle diameter 150nm, solid content concentration 10% by mass)

(mold release agent solution X-1)

100 parts by mass of a thermosetting aminoalkyd resin (Tesfine 314, solid content 60% by mass, available from hitachi chemical corporation) and 1.2 parts by mass of p-toluenesulfonic acid (solid content 50% by mass, available from hitachi chemical corporation) as a curing catalyst were diluted with a toluene/methyl ethyl ketone/heptane (3: 5: 2) solution to prepare a mold release agent solution having a solid content of 2% by mass.

(mold release agent solution X-2)

100 parts by mass of a UV curable silicone resin (UV 9300, solid content concentration 100% by mass, manufactured by Momentive corporation) and 1 part by mass of a curing catalyst bis (alkylphenyl) iodonium hexafluoroantimonate were diluted with a toluene/methyl ethyl ketone/heptane (3: 5: 2) solution to prepare a mold release agent solution having a solid content of 2% by mass.

(example 1)

(preparation of coating solution for easy slip 1)

The following composition of easy-slip coating liquid 1 was adjusted.

(Yishu coating liquid 1)

41.86 parts by mass of water

35.00 parts by mass of isopropyl alcohol

Acrylic polyol resin A-116.57 parts by mass

(solid content concentration 20% by mass)

5.68 parts by mass of oxazoline-based crosslinking agent D-1 (solid content concentration: 25% by mass)

Silica particles G-10.59 parts by mass

(average particle diameter 200nm, solid content concentration 40% by mass)

0.30 part by mass of surfactant H-1 (fluorine-based, solid content concentration 10% by mass)

(production of polyester film)

PET resin pellets (PET (ii)) having an intrinsic viscosity (solvent: phenol/tetrachloroethane: 60/40) of 0.62dl/g as a film raw material polymer and containing substantially no particles were dried at 135 ℃ for 6 hours under a reduced pressure of 133 Pa. Thereafter, the sheet was fed to an extruder, melt-extruded at about 280 ℃ into a sheet, and cooled, closely adhered and solidified on a rotating cooling metal roll whose surface temperature was kept at 20 ℃ to obtain an undrawn PET sheet.

The unstretched PET sheet was heated to 100 ℃ in a heated roll set and an infrared heater, and then stretched 3.5 times in the longitudinal direction on the roll set having a peripheral speed difference to obtain a uniaxially stretched PET film.

Subsequently, the above-mentioned easy-slip coating liquid was applied to one surface of a PET film by a bar coater, and then dried at 80 ℃ for 15 seconds. The coating weight after final stretching and drying was adjusted to 0.1 μm. Subsequently, the film was stretched at 150 ℃ in the width direction by a factor of 4.0, heated at 230 ℃ for 0.5 second with the length of the film in the width direction fixed, and further subjected to a 3% relaxation treatment at 230 ℃ for 10 seconds to obtain an in-line coated polyester film having a thickness of 31 μm in a tenter.

(formation of mold-releasing coating layer)

On the in-line coated polyester film obtained in the above, a release agent solution X-1 was applied by a reverse gravure coater to a surface opposite to the laminated surface of the easy-to-slip coating layer so that the thickness after drying became 0.1 μm, and then dried in hot air at 130 ℃ for 30 seconds to form a release coating layer, thereby obtaining a release film for producing an ultrathin ceramic green sheet. The properties such as winding ability, process passability and handling properties are excellent without any particular problem. After winding in the form of a roll, the unwinding electrification at the time of rewinding for coating the ceramic sheet is also low, and the adhesion of environmental foreign matter can be suppressed, and a ceramic capacitor of good quality can be produced without lowering the yield of the ceramic capacitor.

(example 2)

A release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1 except that the easy-slip coating liquid 2 was used in which the crosslinking agent in the easy-slip coating liquid 1 used in example 1 was changed to the carbodiimide-based crosslinking agent E-1 (solid content concentration: 40 mass%).

(Yi-SLIP COATING LIQUID 2)

43.99 parts by mass of water

35.00 parts by mass of isopropyl alcohol

Acrylic polyol resin A-116.57 parts by mass

(solid content concentration 20% by mass)

13.55 parts by mass of carbodiimide crosslinking agent E-13

(solid content concentration 40% by mass)

Silica particles G-10.59 parts by mass

(average particle diameter 200nm, solid content concentration 40% by mass)

(example 3)

A release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1 except that the easy-slip coating liquid 3 was used in which the crosslinking agent in the easy-slip coating liquid 1 used in example 1 was changed to the oxazoline crosslinking agent D-2 (solid content concentration: 10 mass%).

(Yi-SLIP coating liquid 3)

33.34 parts by mass of water

35.00 parts by mass of isopropyl alcohol

Acrylic polyol resin A-116.57 parts by mass

(solid content concentration 20% by mass)

Oxazoline crosslinking agent D-214.20 parts by mass

(solid content concentration 10% by mass)

Silica particles G-10.59 parts by mass

(average particle diameter 200nm, solid content concentration 40% by mass)

(example 4)

A release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1, except that the coating solution 1 was changed to the coating solution 4 described below.

(Yi-SLIP COATING LIQUID 4)

43.28 parts by mass of water

35.00 parts by mass of isopropyl alcohol

Acrylic polyol resin A-19.47 parts by mass

(solid content concentration 20% by mass)

Oxazoline crosslinking agent D-111.36 parts by mass

(solid content concentration 25% by mass)

Silica particles G-10.59 parts by mass

(average particle diameter 200nm, solid content concentration 40% by mass)

(example 5)

A release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1, except that the coating solution 1 was changed to the coating solution 5 described below.

(Yi-SLIP COATING LIQUID 5)

41.15 parts by mass of water

35.00 parts by mass of isopropyl alcohol

Acrylic polyol resin A-120.12 parts by mass

(solid content concentration 20% by mass)

2.84 parts by mass of oxazoline-based crosslinking agent D-1 (solid content concentration: 25% by mass)

Silica particles G-10.59 parts by mass

(average particle diameter 200nm, solid content concentration 40% by mass)

(example 6)

A mold release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1 except that the acrylic polyol A-1 (solid content concentration: 20% by mass) in the easy-to-slide coating liquid 1 used in example 1 was changed to acrylic polyol A-2 (solid content concentration: 20% by mass).

(example 7)

A mold release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1 except that the acrylic polyol A-1 (solid content concentration: 20% by mass) in the easy-to-slide coating liquid 1 used in example 1 was changed to acrylic polyol A-3 (solid content concentration: 20% by mass).

(example 8)

A mold release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1 except that the acrylic polyol A-1 (solid content concentration: 20% by mass) in the easy-to-slide coating liquid 1 used in example 1 was changed to acrylic polyol A-4 (solid content concentration: 20% by mass).

(example 9)

A mold release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1 except that the acrylic polyol A-1 (solid content concentration: 20% by mass) in the easy-to-slide coating liquid 1 used in example 1 was changed to acrylic polyol A-5 (solid content concentration: 20% by mass).

(example 10)

A mold release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1 except that the acrylic polyol A-1 (solid content concentration: 20% by mass) in the easy-to-slide coating liquid 1 used in example 1 was changed to acrylic polyol A-6 (solid content concentration: 20% by mass).

(example 11)

A mold release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1 except that the acrylic polyol A-1 (solid content concentration: 20% by mass) in the easy-to-slide coating liquid 1 used in example 1 was changed to acrylic polyol A-7 (solid content concentration: 20% by mass).

(example 12)

A mold release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1 except that the acrylic polyol A-1 (solid content concentration: 20% by mass) in the easy-to-slide coating liquid 1 used in example 1 was changed to acrylic polyol A-8 (solid content concentration: 20% by mass).

(example 13)

A mold release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1 except that the acrylic polyol A-1 (solid content concentration: 20% by mass) in the easy-to-slide coating liquid 1 used in example 1 was changed to acrylic polyol A-9 (solid content concentration: 20% by mass).

(example 14)

A mold release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1 except that the acrylic polyol A-1 (solid content concentration: 20% by mass) in the easy-to-slide coating liquid 1 used in example 1 was changed to acrylic polyol A-10 (solid content concentration: 20% by mass).

(example 15)

A mold release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1 except that the acrylic polyol A-1 (solid content concentration: 20% by mass) in the easy-to-slide coating liquid 1 used in example 1 was changed to acrylic polyol A-11 (solid content concentration: 20% by mass).

(example 16)

A mold release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1 except that the acrylic polyol A-1 (solid content concentration: 20% by mass) in the easy-to-slide coating liquid 1 used in example 1 was changed to acrylic polyol A-12 (solid content concentration: 20% by mass).

(example 17)

A release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1, except that the coating solution 1 was changed to the coating solution 17 described below.

(Yi-SLIP COATING LIQUID 17)

41.74 parts by mass of water

35.00 parts by mass of isopropyl alcohol

Acrylic polyol resin A-1016.57 parts by mass

(solid content concentration 20% by mass)

Silica particles G-10.59 parts by mass

(average particle diameter 200nm, solid content concentration 40% by mass)

Silica particles G-40.12 parts by mass

(average particle diameter 450nm, solid content concentration 40% by mass)

(example 18)

A release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1, except that the coating solution 1 was changed to the coating solution 18 described below.

(Yishu coating liquid 18)

41.15 parts by mass of water

35.00 parts by mass of isopropyl alcohol

Acrylic polyol resin A-1016.57 parts by mass

(solid content concentration 20% by mass)

Silica particles G-21.18 parts by mass

(average particle diameter 40nm, solid content concentration 40% by mass)

Silica particles G-40.12 parts by mass

(average particle diameter 450nm, solid content concentration 40% by mass)

(example 19)

A release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1, except that the coating solution 1 was changed to the following coating solution 19.

(Yi-SLIP COATING LIQUID 19)

41.27 parts by mass of water

35.00 parts by mass of isopropyl alcohol

Acrylic polyol resin A-1016.57 parts by mass

(solid content concentration 20% by mass)

15.68 parts by mass of oxazoline cross-linking agent D

(solid content concentration 25% by mass)

Silica particles G-31.18 parts by mass

(average particle diameter 100nm, solid content concentration 40% by mass)

(example 20)

A release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1, except that the coating solution 1 was changed to the coating solution 20 described below.

(Yishu coating liquid 20)

40.09 parts by mass of water

35.00 parts by mass of isopropyl alcohol

Acrylic polyol resin A-1016.57 parts by mass

(solid content concentration 20% by mass)

Acrylic acid particles G-52.37 parts by mass

(average particle diameter 150nm, solid content concentration 10% by mass)

(example 21)

A release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1, except that the formation of the release coating layer was performed as described below.

(formation of mold-releasing coating layer)

The obtained in-line coated polyester film was coated with a release agent solution X-2 by a reverse gravure coater so that the thickness of the film became 0.1. mu.m after drying, and then dried in hot air at 90 ℃ for 30 seconds, and immediately thereafter irradiated with ultraviolet rays (300 mJ/cm) by an electrodeless lamp (manufactured by fusion Co., Ltd., H valve)²) A release coating layer was formed to obtain a release film for producing an ultrathin ceramic green sheet.

(example 22)

A release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1, except that the coating solution 1 was changed to the following coating solution 21.

(Yi-SLIP COATING LIQUID 21)

47.39 parts by mass of water

35.00 parts by mass of isopropyl alcohol

Aqueous polyester dispersion B-311.04 parts by mass

(Toyo textile, Vylonal (registered trademark) MD1500, Tg 77 ℃, solid content concentration 30 mass%)

Silica particles G-10.59 parts by mass

(average particle diameter 200nm, solid content concentration 40% by mass)

0.30 part by mass of a surfactant (fluorine-based, solid content concentration 10% by mass)

Comparative example 1

A release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1, except that the coating solution 1 was changed to the coating solution 22 described below.

(Yi-SLIP COATING LIQUID 22)

48.33 parts by mass of water

35.00 parts by mass of isopropyl alcohol

Aqueous polyester dispersion B-115.78 parts by mass

(solid content concentration 30% by mass)

Silica particles G-10.59 parts by mass

(average particle diameter 200nm, solid content concentration 40% by mass)

Comparative example 2

A release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1, except that the coating solution 1 was changed to the coating solution 23 described below.

(Yi-SLIP COATING LIQUID 23)

45.18 parts by mass of water

35.00 parts by mass of isopropyl alcohol

Aqueous polyester dispersion B-218.93 parts by mass

(solid content concentration 25% by mass)

Silica particles G-10.59 parts by mass

(average particle diameter 200nm, solid content concentration 40% by mass)

Comparative example 3

A release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1, except that the coating solution 1 was changed to the coating solution 24 described below.

(Yi-SLIP coating liquid 24)

51.32 parts by mass of water

35.00 parts by mass of isopropyl alcohol

Aqueous polyurethane resin dispersion C-112.79 parts by mass

(solid content concentration 37% by mass)

Silica particles G-10.59 parts by mass

(average particle diameter 200nm, solid content concentration 40% by mass)

Comparative example 4

A release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1, except that the coating solution 1 was changed to the coating solution 25 described below.

(Yishu coating liquid 25)

47.39 parts by mass of water

35.00 parts by mass of isopropyl alcohol

11.04 parts by mass of aqueous polyester dispersion B-1 (solid content concentration 30% by mass)

Silica particles G-10.59 parts by mass

(average particle diameter 200nm, solid content concentration 40% by mass)

Comparative example 5

A release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1, except that the coating solution 1 was changed to the below-described coating solution 26.

(Yishu coating liquid 26)

49.51 parts by mass of water

35.00 parts by mass of isopropyl alcohol

Aqueous polyester dispersion B-111.04 parts by mass

(solid content concentration 30% by mass)

13.55 parts by mass of carbodiimide crosslinking agent E-13

(solid content concentration 40% by mass)

Silica particles G-10.59 parts by mass

(average particle diameter 200nm, solid content concentration 40% by mass)

Comparative example 6

A release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1, except that the coating solution 1 was changed to the following coating solution 27.

(Yi-SLIP COATING LIQUID 27)

40.44 parts by mass of water

35.00 parts by mass of isopropyl alcohol

Acrylic polyol resin A-123.67 parts by mass

(solid content concentration 20% by mass)

Silica particles G-10.59 parts by mass

(average particle diameter 200nm, solid content concentration 40% by mass)

Comparative example 7

A release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1, except that the coating solution 1 was changed to the coating solution 28 described below.

(Yi-SLIP COATING LIQUID 28)

45.65 parts by mass of water

35.00 parts by mass of isopropyl alcohol

Acrylic polyol resin A-116.57 parts by mass

(solid content concentration 20% by mass)

1.89 parts by mass of isocyanate crosslinking agent F-1 (solid content concentration 75% by mass)

Silica particles G-10.59 parts by mass

(average particle diameter 200nm, solid content concentration 40% by mass)

Comparative example 8

A release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1, except that the release film for forming a release coating layer was used in place of the in-line coated film having an easily slippery coating layer on one surface prepared in example 1, except that the thickness was changed to E5000 to 25 μm (manufactured by tokyo corporation). E5000 contains particles in the film, and Sa of both surfaces is 0.031 μm.

Comparative example 9

A release film for producing an ultrathin ceramic green sheet was obtained in the same manner as in example 1, except that the film for forming a release coating layer was used instead of the in-line coated film having an easy-to-slip coating layer on one surface prepared in example 1, and the laminated film Z was used. A release coat layer was provided on the surface (layer containing no particles) of the laminated film Z from which the pet (ii) pellets were discharged.

The evaluation results of the examples and comparative examples are shown in table 2.

[ Table 2]

In table 2, the compositions of the resin, the crosslinking agent, the particles, and the surfactant in the slip-facilitating coating liquid are described in parts by mass of the solid content, the sum of the parts by mass of the solid content of the resin, the crosslinking agent, the particles, and the surfactant in the slip-facilitating coating liquid is the part by mass of the entire solid content of the slip-facilitating coating layer, and the mass percentage of the resin, the crosslinking agent, the particles, and the surfactant in the entire solid content of the slip-facilitating coating layer is determined by dividing the part by mass of the solid content of the slip-facilitating coating layer by the part by mass of the entire solid content of the slip-facilitating coating layer.

In examples 1 to 22, since the unwinding electrification at the time of rewinding the roll after the mold release processing was low and the environmental foreign matter was not easily attached, the ceramic capacitor with good quality could be produced without lowering the yield of the ceramic capacitor. As the release film, a polyester film substantially free of inorganic particles is used as a base material, a release coating layer is provided on one surface of the base material, and an easy-slip coating layer containing particles is provided on the other surface, and the March Hardness (HM) of a mixed composition single film of a resin of the easy-slip coating layer and a crosslinking agent is 150N/mm²Further, it is considered that the elastic deformation power (η it) is 28% or more, and therefore, the pressure during unwinding of the film roll becomes small, and the deformation of the easy-to-slip coating layer is immediately recovered, and the contact area between the easy-to-slip coating layer and the release layer during unwinding of the film roll becomes small, and therefore, the amount of electrification can be suppressed.

On the other hand, in comparative examples 1 to 7, the ranges of the mahalanobis Hardness (HM) and the elastic deformation power (η it) of the single film of the mixed composition of the resin and the crosslinking agent of the easily slippery coating layer specified in the present invention were not satisfied, and therefore, it is considered that the contact area when the release coating layer and the easily slippery coating layer are peeled off from the release-processed film roll, and the unwinding electrification becomes large, and in comparative examples 8 and 9, the unwinding electrification is low, but the easily slippery coating layer specified in the present invention is not present, and the surface roughness of the easily slippery surface is large, and therefore, pinholes are generated in the ceramic sheet.

Industrial applicability

According to the present invention, there can be provided: when the ceramic green sheet is made thin, a release film for producing a ceramic green sheet can be provided which prevents the adhesion of environmental foreign matter due to electrification by preventing pinholes, partial thickness unevenness, and the like. Further, by using the release film for producing a ceramic green sheet of the present invention, an extremely thin ceramic green sheet can be obtained, and a minute ceramic capacitor can be efficiently produced.

Claims

1. A release film for producing a ceramic green sheet, comprising a polyester film substantially free of inorganic particles as a base material, a release coating layer on one surface of the base material, and an easy-slip coating layer comprising particles on the other surface, wherein the easy-slip coating layer has a regional surface average roughness (Sa) of 1nm to 25nm, a maximum protrusion height (P) of 60nm to 500nm, and a contour unit average width (RSm) of 10 [ mu ] m or less, and wherein a mixed composition single film of a resin of the easy-slip coating layer and a crosslinking agent has a Mahalanobis Hardness (HM) of 150N/mm²The above, and the elastic deformation power (η it) is 28% or more.

2. The release film for producing a ceramic green sheet according to claim 1, wherein the slip-susceptible coating layer is obtained by curing a composition containing an acrylic resin and at least 1 crosslinking agent selected from an oxazoline crosslinking agent and a carbodiimide crosslinking agent.

3. The release film for producing a ceramic green sheet according to claim 1 or 2, wherein the thickness of the easy-slip coating layer is 0.001 μm or more and 2 μm or less.

4. A method for producing a ceramic green sheet, which comprises using the release film for producing a ceramic green sheet according to any one of claims 1 to 3.

5. The method of manufacturing a ceramic green sheet according to claim 4, wherein the thickness of the ceramic green sheet to be manufactured is 0.2 μm or more and 2.0 μm or less.

6. A method for producing a ceramic capacitor using the method for producing a ceramic green sheet according to claim 4 or 5.