KR20240074885A - Release film - Google Patents

Abstract

[Problem] To provide an excellent release film for producing ceramic green sheets that can achieve both good winding properties and prevention of pinholes and partial thickness fluctuations even when the ceramic green sheets are thinned. [Solution] A polyester film containing substantially no particles is used as the base material, and the base material has a release coating layer on one surface and a release coating layer containing particles on the other surface. , A release film for manufacturing ceramic green sheets with an average surface roughness (Sa) of the area of the lubricating coating layer of 1 nm to 25 nm, a maximum protrusion height (P) of 60 nm to 500 nm, and an average length of roughness curve elements (RSm) of 10 ㎛ or less. .

Description

Release film {RELEASE FILM}

The present invention relates to a release film for manufacturing ceramic green sheets. More specifically, it relates to a release film for producing ceramic green sheets that can achieve both good winding properties and prevention of pinholes and partial thickness fluctuations, even when the ceramic green sheets are thinned.

Conventionally, by relatively roughening the surface roughness of the side (back side) of the base film opposite to the side on which the release agent layer is installed, the front and back of the release film for producing ceramic green sheets adheres when the release film for producing ceramic green sheets is stored in a wound state. A technology to solve problems such as blocking has been disclosed (for example, see Patent Document 1). However, this prior art had a problem in that pinholes or partial thickness variations occurred because the protrusions were large.

Therefore, in order to reduce the height of the protrusions, a technology has been disclosed that attempts to prevent pinholes or partial thickness fluctuations from occurring in the ceramic green sheet by embedding the protrusions on the back side with an application layer (for example, Patent Document 2 reference). However, according to this prior art, although the protrusion height is lowered, the protrusion density is low, so the pressure applied to the protrusion is large, and when the ceramic green sheet is made thinner, there is a problem in that pinholes occur.

Japanese Patent Publication No. 2003-203822 Japanese Patent Publication No. 2014-144636

The present invention was made against the background of these problems of the prior art. That is, the purpose of the present invention is to provide an excellent release film for producing ceramic green sheets that can achieve both good winding properties and prevention of pinholes and partial thickness fluctuations even when the ceramic green sheets are thinned.

As a result of intensive studies to achieve this objective, the present inventor has reached completion of the present invention. That is, the present invention includes the following configurations.

1. A polyester film substantially free of particles is used as the base material, has a release coating layer on one surface of the base material, and has a release coating layer containing particles on the other surface, and has a release coating layer containing particles, and has a release coating layer containing particles on the other surface. For manufacturing ceramic green sheets, characterized in that the average surface roughness (Sa) of the application layer is 1 nm to 25 nm, the maximum protrusion height (P) is 60 nm to 500 nm, and the average length of the roughness curve elements (RSm) is 10 μm or less. Release film.

2. The release film for producing a ceramic green sheet according to the first item, wherein the average surface roughness (Sa) of the release coating layer is 5 nm or less and the maximum protrusion height (P) is 30 nm or less.

3. The release film for manufacturing a ceramic green sheet according to the first or second item, wherein the thickness of the lubricating coating layer is 0.001 ㎛ or more and 2 ㎛ or less.

4. A method for producing a ceramic green sheet, characterized by using the release film for producing a ceramic green sheet according to any one of the first to third items.

5. The method for producing a ceramic green sheet according to item 4, wherein the thickness of the ceramic green sheet to be produced is 0.2 μm or more and 2 μm or less.

6. A method for manufacturing a ceramic capacitor, characterized by employing the method for manufacturing a ceramic green sheet according to item 4 or 5 above.

According to the present invention, it is possible to provide a release film for producing ceramic green sheets that can achieve both good winding and prevention of pinholes and partial thickness fluctuations, even when the ceramic green sheets are thinned.

Hereinafter, the present invention will be described in detail.

The release film for producing ceramic green sheets (hereinafter sometimes simply referred to as release film) of the present invention has a release coating layer on one side of a biaxially oriented polyester film as a base film, and a release coating layer containing particles on the other side. It is a release film with .

(Base film)

The film preferably used as a base material in the present invention is a film composed of polyester resin, and mainly contains at least one selected from polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate. Polyester films are preferred. Additionally, it may be a film containing a polyester in which a third component monomer is copolymerized as a part of the dicarboxylic acid component or diol component of the polyester described above. Among these polyester films, polyethylene terephthalate film is most preferable from the balance of physical properties and cost.

In addition, the above-mentioned polyester film may be a single layer or a multiple layer. In addition, as long as it is within the range that exhibits the effect of the present invention, various additives can be contained in the polyester resin as needed in each of these layers. Examples of additives include antioxidants, anti-glare agents, anti-gelling agents, organic wetting agents, antistatic agents, and ultraviolet absorbers.

(Removable coating layer)

The release film of the present invention has a lubricant coating layer on one surface of the polyester base film as described above. It is preferable that the easily lubricated coating layer contains at least a binder resin and particles.

(Binder resin in the lubricant coating layer)

The binder resin constituting the easily lubricated coating layer is not particularly limited, but specific examples of polymers include polyester resin, acrylic resin, urethane resin, polyvinyl resin (polyvinyl alcohol, etc.), polyalkylene glycol, polyalkylene imine, Examples include methylcellulose, hydroxycellulose, and starches. Among these, it is preferable to use polyester resin, acrylic resin, and urethane resin from the viewpoint of particle retention and adhesion. Additionally, when considering familiarity with polyester films, polyester resins are particularly preferred. In order to achieve solubility in solvents, dispersibility, and further adhesion to the base film or other layers, the polyester of the binder is preferably a copolyester. Additionally, the polyester resin may be polyurethane-modified. Additionally, another preferred binder resin constituting the lubricant coating layer on the polyester base film includes urethane resin. Examples of the urethane resin include polycarbonate polyurethane resin. In addition, polyester resin and polyurethane resin may be used together, and the other binder resins mentioned above may be used together.

(Cross-linking agent)

In the present invention, in order to form a crosslinked structure in the easily lubricated coating layer, the easily lubricated coating layer may be formed with a crosslinking agent included. By containing a crosslinking agent, it becomes possible to further improve adhesion under high temperature and high humidity. Specific crosslinking agents include urea-based, epoxy-based, melamine-based, isocyanate-based, oxazoline-based, carbodiimide-based, etc. Additionally, in order to promote the crosslinking reaction, a catalyst or the like can be appropriately used as needed.

(Particles in the smooth coating layer)

The lubricant coating layer preferably contains lubricant particles in order to provide slipperiness to the surface. The particles may be inorganic particles or organic particles, and are not particularly limited, but are (1) silica, kaolinite, talc, light calcium carbonate, heavy calcium carbonate, zeolite, alumina, barium sulfate, carbon black, zinc oxide, zinc sulfate, carbonic acid. Inorganic particles such as zinc, zirconium oxide, titanium dioxide, satin white, aluminum silicate, diatomaceous earth, calcium silicate, aluminum hydroxide, hydrous halloysite, calcium carbonate, magnesium carbonate, calcium phosphate, magnesium hydroxide, and barium sulfate, (2) acrylic or Methacrylic, vinyl chloride, vinyl acetate, nylon, styrene/acrylic, styrene/butadiene, polystyrene/acrylic, polystyrene/isoprene, polystyrene/isoprene, methyl methacrylate/butyl methacrylate, melamine, Organic particles such as polycarbonate-based, urea-based, epoxy-based, urethane-based, phenol-based, diallyl phthalate-based, and polyester-based particles may be mentioned, but silica is particularly preferred in order to provide appropriate slipperiness to the coating layer. It is used.

The average particle diameter of the particles is preferably 10 nm or more, more preferably 20 nm or more, and even more preferably 30 nm or more. It is preferable that the average particle diameter of the particles is 10 nm or more because it is difficult to agglomerate and slipperiness can be ensured.

The average particle diameter of the particles is preferably 1000 nm or less, more preferably 800 nm or less, and even more preferably 600 nm or less. It is preferable that the average particle diameter of the particles is 1000 nm or less because transparency is maintained and particles do not fall off.

In addition, for example, mixing small particles with an average particle diameter of about 10 to 200 nm and large particles with an average particle diameter of about 300 to 1000 nm can reduce the average surface roughness (Sa) and maximum protrusion height (P) of the area, which will be described later. It is preferable to reduce the average length (RSm) of the roughness curve elements and achieve both slipperiness and smoothness while maintaining it, and particularly preferably, small particles of 30 nm or more and 150 nm or less and large particles with an average particle diameter of 350 to 600 nm are used. It is used together. When small particles and large particles are mixed, it is desirable to make the mass content of the small particles larger than the mass content of the large particles with respect to the entire solid content of the coating layer.

The method of measuring the average particle size of particles is to observe particles in the cross section of the film after processing with a transmission electron microscope or scanning electron microscope, observe 100 non-agglomerated particles, and use the average value to determine the average particle size. It was done.

As long as it satisfies the purpose of the present invention, the shape of the particles is not particularly limited, and spherical particles or irregular non-spherical particles can be used. The particle diameter of irregular particles can be calculated as the equivalent circle diameter. The equivalent circle diameter is a value obtained by dividing the area of the observed particle by π, calculating the square root, and doubling it.

The ratio of the particles to the total solid content of the lubricating 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. If the ratio of particles to the total solid content of the lubricant coating layer is 50% by mass or less, transparency is maintained and particles do not significantly fall off from the lubricant coating layer, so it is preferable.

The ratio of the particles to the total solid content of the lubricating coating layer is preferably 1% by mass or more, more preferably 1.5% by mass or more, and even more preferably 2% by mass or more. It is preferable that the ratio of particles to the total solid content of the lubricant coating layer is 1% by mass or more because slipperiness can be ensured.

As a method of measuring the content of particles contained in the lubricant coating layer, for example, when the lubricant coating layer contains organic component resin and inorganic particles, the following method can be used. First, the lubricant coating layer provided on the processed film is extracted from the processed film using a solvent or the like and dried to remove the lubricant coating layer. Next, heat is applied to the obtained lubricant coating layer, and the organic components contained in the lubricant coating layer are burned and distilled away by heat to obtain only the inorganic components. By measuring the weight of the obtained inorganic component and the lubricant coating layer before combustion and distillation, the mass% of particles contained in the lubricant coating layer can be measured. At this time, it is possible to measure with high precision by using a commercially available simultaneous differential heat and thermogravimetric measurement device.

(Additives in the lubricating coating layer)

In order to provide other functionality to the easily lubricated coating layer, various additives may be contained within the range of not damaging the coated appearance. Examples of the additive include fluorescent dyes, fluorescent whitening agents, plasticizers, ultraviolet absorbers, pigment dispersants, suppressors, anti-foaming agents, and preservatives.

The easily lubricated coating layer may contain a surfactant for the purpose of improving leveling properties during application and defoaming the coating liquid. The surfactant may be cationic, anionic, or nonionic, but silicone-based, acetylene glycol-based, or fluorine-based surfactants are preferred. It is preferable to contain these surfactants in the application layer to the extent that excessive addition does not cause abnormalities in the applied appearance.

As the application method, both the so-called in-line coating method, which applies simultaneously when forming a polyester base film, and the so-called offline coating method, which applies it with a separate coater after forming the polyester base film, can be applied, but the in-line coating method is efficient and more preferable. do.

As an application method, any known method can be used for applying the coating liquid to a polyethylene terephthalate (hereinafter sometimes abbreviated as PET) film. For example, reverse roll coating method, gravure coating method, kiss coating method, die coater method, roll brush method, spray coating method, air knife coating method, wire bar coating method, pipe doctor method, impregnation coating method, curtain coating method. etc. can be mentioned. These methods are applied singly or in combination.

In the present invention, a method of forming an easily lubricated coating layer on a polyester film includes applying a coating liquid containing a solvent, particles, and resin to the polyester film and drying it. Examples of the solvent include organic solvents such as toluene, water, or a mixture of water and a water-soluble organic solvent. However, from environmental concerns, a so-called aqueous solvent containing water alone or water mixed with a water-soluble organic solvent is preferred. do.

The solid content concentration of the lubricant coating liquid varies depending on the type of binder resin, the type of solvent, etc., but 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 application also varies depending on the type of binder resin, the type of solvent, the presence or absence of a crosslinking agent, solid content concentration, etc., but is preferably 70°C or higher, and is preferably 250°C or lower.

(Manufacture of polyester film)

In the present invention, the polyester film used as the base film can be manufactured according to a general polyester film manufacturing method. For example, the polyester resin is melted, the non-oriented polyester extruded into a sheet is stretched in the longitudinal direction using the speed difference of the roll at a temperature above the glass transition temperature, and then stretched in the transverse direction by a tenter. and a method of performing heat treatment. In addition, a method of stretching in two directions simultaneously in the longitudinal and transverse directions within a tenter is also possible.

In the present invention, the polyester film serving as the base film may be a uniaxially stretched film or a biaxially stretched film, but is preferably a biaxially stretched film.

The thickness of the polyester film base material is preferably 5 μm or more, more preferably 10 μm or more, and still more preferably 15 μm or more. A thickness of 5 μm or more is preferable because it is difficult for wrinkles to form during conveyance of the film.

The thickness of the polyester film base material is preferably 50 μm or less, more preferably 45 μm or less, and still more preferably 40 μm or less. A thickness of 40 μm or less is preferable because the cost per unit area decreases.

In the case of in-line coating, it may be applied to an unstretched film before stretching in the longitudinal direction, or to a uniaxially stretched film after stretching in the vertical direction but before stretching in the transverse direction. When coating before stretching in the longitudinal direction, it is preferable to provide a drying process before roll stretching. In the case of coating on a uniaxially stretched film before stretching in the transverse direction, the drying process can also be used as the film heating process in the tenter, so there is no need to necessarily provide a separate drying process. Additionally, the same applies to simultaneous biaxial stretching.

The film thickness of the lubricating coating layer is preferably 0.001 μm or more, more preferably 0.01 μm or more, further preferably 0.02 μm or more, and particularly preferably 0.03 μm or more. It is preferable that the film thickness of the coating layer is 0.001 μm or more because the film-forming properties of the coating film are maintained and a uniform coating film is obtained.

The film thickness of the lubricant coating layer is preferably 2 μm or less, more preferably 1 μm or less, further preferably 0.8 μm or less, and particularly preferably 0.5 μm or less. It is preferable that the film thickness of the application layer is 2 μm or less because there is no risk of blocking occurring.

The ceramic green sheet applied and molded on the release coating layer described later is wound into a roll together with the release film after application and molding. At this time, the ceramic green sheet is wound while the smooth coating layer of the release film is in contact with the surface. In order to prevent defects from occurring on the surface of the ceramic green sheet, the outer surface of the lubricant coating layer (the surface of the lubricant coating layer of the entire coated film that is not in contact with the polyester film) must be appropriately flat, and the area surface average roughness (Sa) ) is preferably 1 nm or more and 25 nm or less, and the maximum protrusion height (P) is preferably 60 nm or more and 500 nm or less.

It is preferable that the regional surface average roughness (Sa) of the outer surface of the lubricant coating layer is 1 nm or more and the maximum protrusion height (P) is 60 nm or more because the lubricant coating surface does not become too smooth and can maintain appropriate slipperiness. It is preferable that the average surface roughness (Sa) of the region is 25 nm or less and the maximum protrusion height (P) is 500 nm or less because the lubricated coated surface does not become too rough and defects in the ceramic green sheet due to protrusions do not occur.

In the present invention, in addition to setting the regional surface average roughness (Sa) and maximum protrusion height (P) within the above range, it is preferable that the average length (RSm) of the roughness curve elements is 10 μm or less. By controlling the average length (RSm) of the roughness curve elements to 10 μm or less, the number of protrusions per unit area increases. As the number of protrusions increases, the pressure applied to each protrusion is distributed and becomes smaller, which is desirable because the generation of pinholes can be effectively suppressed. The average length (RSm) of the roughness curve elements is more preferably 5 μm or less, and even more preferably 3 μm or less. However, the reason that the average length (RSm) of the roughness curve elements is too small is that the area surface average roughness (Sa) increases and the maximum protrusion height (P) increases due to the fact that the particle content in the lubricating coating layer is too high. Since it is also related to this, it is preferably 0.1 μm or more, may be 0.5 μm or more, and may be 1 μm or more.

In the present invention, in order to keep the average length (RSm) of the roughness curve elements within a predetermined range, it is preferable that the average particle diameter of the particles contained in the lubricating coating layer is 1000 nm or less. More preferably, it is 800 nm or less, and even more preferably, it is 600 nm or less. It is preferable that the particle diameter is 1000 nm or less because the distance between particles does not become too large and RSm is adjusted to a predetermined range.

(Releasing coating layer)

There is no particular limitation on the resin constituting the release coating layer in the present invention, and silicone resins, fluororesins, alkyd resins, various waxes, aliphatic olefins, etc. can be used, and each resin can be used alone or in combination of two or more types. .

As the release coating layer of the present invention, for example, silicone resin is a resin having a silicone structure in the molecule, and includes curable silicone, silicone graft resin, and modified silicone resin such as alkyl modification. However, from the viewpoint of transferability, etc. It is preferred to use a reactive curing silicone resin. As the reactive curing silicone resin, addition reaction type, condensation reaction type, ultraviolet ray or electron beam curing type, etc. can be used. More preferably, those of a low-temperature curable addition reaction system that can be processed at low temperatures, and those of an ultraviolet ray or electron beam curing system are good. By using these, processing can be done at low temperature during coating processing into a polyester film. Therefore, there is less heat damage to the polyester film during processing, a polyester film with high planarity is obtained, and defects such as pinholes can be reduced even when producing ultra-thin ceramic green sheets with a thickness of 0.2 to 2 μm. there is.

Examples of addition reaction-based silicone resins include those that are cured by reacting polydimethylsiloxane with a vinyl group introduced into the terminal or side chain and hydrogensiloxane using a platinum catalyst. At this time, it is more preferable to use a resin that can be cured at 120°C within 30 seconds because it allows processing at low temperatures. Examples include low-temperature addition curing type (LTC1006L, LTC1056L, LTC300B, LTC303E, LTC310, LTC314, LTC350G, LTC450A, LTC371G, LTC750A, LTC755, LTC760A, etc.) and heat UV curing type (LTC851, BY24- 510, BY24- 561, BY24-562, etc.), solvent addition + UV curing type (X62-5040, X62-5065, 1980, etc.), etc.

Examples of condensation reaction-based silicone resins include those made by condensing polydimethylsiloxane having an OH group at the terminal and polydimethylsiloxane having an H group at the terminal using an organic tin catalyst to create a three-dimensional crosslinked structure.

As for the ultraviolet curing silicone resin, for example, the most basic type is one that uses a radical reaction like normal silicone rubber crosslinking, one that introduces an unsaturated group and photocures it, and one that decomposes an onium salt under ultraviolet rays to generate a strong acid. Examples include crosslinking by cleavage of the epoxy group, crosslinking through addition reaction of thiol to vinylsiloxane, etc. Additionally, electron beams may be used instead of the ultraviolet rays. Electron beams have stronger energy than ultraviolet rays, and in the case of ultraviolet curing, it is possible to perform a crosslinking reaction by radicals even without using an initiator. Examples of resins to be used include UV curing silicone (X62-7028A/B, X62-7052, X62-7205, X62-7622, X62-7629, UV curing silicone made by Materials (TPR6502, TPR6501, TPR6500, UV9300, UV9315, UV265AM, etc.) can be mentioned.

As the above UV-curable silicone resin, acrylate-modified or glycidoxy-modified polydimethylsiloxane can also be used. Good mold release performance can be achieved by mixing these modified polydimethylsiloxanes with a polyfunctional acrylate resin, epoxy resin, etc. and using them in the presence of an initiator.

Examples of other resins to be used include alkyd resins or acrylic resins modified with stearyl, lauryl, etc., or alkyd resins obtained by reaction of methylated melamine, etc., and acrylic resins are also suitable.

Examples of the aminoalkyd resin obtained through the reaction of the above-mentioned methylated melamine, etc. include Tespine 303, Tespine 305, and Tespine 314 manufactured by Hitachi Chemical Industries, Ltd. Examples of aminoacrylic resins obtained by reaction of methylated melamine, etc. include Tespine 322 manufactured by Hitachi Chemical Industries, Ltd.

When using the above resin in the release coating layer of the present invention, it may be used alone or in combination of two or more types. Additionally, in order to adjust the peeling force, it is also possible to mix additives such as a light peeling additive or a heavy peeling additive.

The release coating layer of the present invention may contain particles having a particle diameter of 1 μm or less, but it is preferable to substantially not contain particles forming protrusions or the like from the viewpoint of pinhole generation.

Additives such as an adhesion improver or an antistatic agent may be added to the release coating layer of the present invention. Additionally, in order to improve adhesion to the substrate, it is also desirable to pre-treat the surface of the polyester film, such as anchor coating, corona treatment, plasma treatment, or atmospheric pressure plasma treatment, before forming the release coating layer.

In the present invention, the thickness of the release coating layer may be set according to the purpose of use and is not particularly limited, but the thickness of the release coating layer after curing is preferably in the range of 0.005 to 2 μm. It is preferable that the thickness of the release coating layer is 0.005 μm or more because peeling performance is maintained. In addition, it is preferable that the thickness of the release coating layer is 2㎛ or less because the curing time does not become too long and there is no risk of uneven thickness of the ceramic green sheet due to a decrease in the planarity of the release film. In addition, since the curing time is not too long, there is no risk of the resin constituting the release coating layer agglomerating, there is no risk of forming protrusions, and pin hole defects in the ceramic green sheet are unlikely to occur, 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 that is not in contact with the polyester film) is preferably flat in order to prevent defects from occurring in the ceramic green sheet to be applied and formed thereon. It is preferable that the area surface average roughness (Sa) is 5 nm or less and the maximum protrusion height (P) is 30 nm or less. Furthermore, it is more preferable that the area surface average roughness (Sa) is 5 nm or less and the maximum protrusion height (P) is 20 nm or less. Particularly preferably, the area surface average roughness (Sa) is 3 nm or less, and the maximum protrusion height (P) is 17 nm or less. If the area surface roughness (Sa) is 5 nm or less and the maximum protrusion height (P) is 30 nm or less, defects such as pinholes do not occur when forming the ceramic green sheet, and the yield is good, which is preferable. It can be said that the smaller the area surface average roughness (Sa) is, the more desirable it is, but it may be 0.1 nm or more, and it may be 0.3 nm or more. It can be said that the smaller the maximum protrusion height (P) is, the more desirable it is, but it does not matter if it is 1 nm or more, and it does not matter if it is 3 nm or more.

In the present invention, in order to adjust the surface of the film on which the release coating layer is formed to a predetermined roughness range, it is preferable that the PET film contains substantially no particles. In addition, in the present invention, "substantially free from particles" refers to both the base film and the release coating layer, for example, in the case of inorganic particles, when the elements derived from the particles are quantitatively analyzed by fluorescence X-ray analysis. It is defined as 50 ppm or less, preferably 10 ppm or less, and most preferably less than the detection limit. This is because even if particles are not actively added to the base film, contaminants derived from foreign substances, raw material resin, or contaminants attached to lines or equipment during the film manufacturing process may peel off and become mixed into the film. .

In the present invention, the method of forming the release coating layer is not particularly limited, and the coating solution in which the release resin is dissolved or dispersed is spread by applying it to one side of the polyester film of the base material, and the solvent, etc. is dried. After removal, heat drying, heat curing, or ultraviolet curing methods are used. At this time, the drying temperature during solvent drying and heat curing is preferably 180°C or lower, more preferably 150°C or lower, and most preferably 120°C or lower. The heating time is preferably 30 seconds or less, and more preferably 20 seconds or less. In the case of 180°C or lower, the flatness of the film is maintained and there is little risk of uneven thickness of the ceramic green sheet, which is preferable. If it is 120°C or lower, it is particularly preferable because the film can be processed without damaging its flatness and the risk of uneven thickness of the ceramic green sheet is further reduced.

In the present invention, the surface tension of the coating liquid when applying the release coating layer is not particularly limited, but is preferably 30 mN/m or less. By maintaining the surface tension as described above, applicability after coating is improved and irregularities on the surface of the coated film after drying can be reduced.

In the present invention, the coating liquid for applying the release coating layer is not particularly limited, but it is preferable to add a solvent with a boiling point of 90°C or higher. By adding a solvent with a boiling point of 90°C or higher, it is possible to prevent stuttering during drying, level the coating film, and improve the smoothness of the surface of the coating film after drying. The addition amount is preferably about 10 to 80% by mass relative to the entire coating liquid.

As the application method of the above-mentioned coating solution, any known application method can be applied, for example, roll coating method such as gravure coating method or reverse coating method, bar coating method such as wire bar, die coating method, or spray coating method. , conventionally known methods such as air knife coating method can be used.

(Ceramic green sheet and ceramic condenser)

Generally, a multilayer ceramic capacitor has a ceramic body in the shape of a rectangular parallelepiped. Inside the ceramic body, first internal electrodes and second internal electrodes are arranged alternately along the thickness direction. The first internal electrode is exposed to the first end surface of the ceramic body. A first external electrode is installed on the first end surface. The first internal electrode is electrically connected to the first external electrode at the first end surface. The second internal electrode is exposed to the second end surface of the ceramic body. A second external electrode is installed on the second end surface. The second internal electrode is electrically connected to the second external electrode at the second end surface.

The release film for producing ceramic green sheets of the present invention is used to produce such a multilayer ceramic capacitor. For example, it is manufactured as follows. First, the release film of the present invention is used as a carrier film, and a ceramic slurry for forming a ceramic body is applied and dried. On the applied and dried ceramic green sheet, a conductive layer for forming the first or second internal electrode is printed. A mother laminate is obtained by appropriately stacking and pressing a ceramic green sheet, a ceramic green sheet printed with a conductive layer for forming the first internal electrode, and a ceramic green sheet printed with a conductive layer for forming the second internal electrode. . The mother laminate is divided into plural parts and a raw ceramic body is produced. A ceramic body is obtained by firing the raw ceramic body. Thereafter, the multilayer ceramic capacitor can be completed by forming the first and second external electrodes.

Example

Next, the present invention will be described in detail using examples and comparative examples, but the present invention is naturally not limited to the following examples. Additionally, the evaluation method used in the present invention is as follows.

(1) Surface characteristics of the applied film

The values were measured under the following conditions using a non-contact surface shape measurement system (VertScan R550H-M100). The average value of five measurements was adopted for the area surface average roughness (Sa) and the average length of roughness curve elements (RSm), and the maximum protrusion height (P) was the maximum value of five measurements.

(Measuring conditions)

·Measurement mode: WAVE mode

·Objective lens: 50x

·0.5×Tube lens

·Measurement area 187×139㎛ (Sa, P measurement)

·Measured length (Lr: standard length): 187㎛ (RSm measurement)

(2) Evaluation of pinholes and thickness fluctuations in ceramic green sheets

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

toluene 22.5% by mass

ethanol 22.5% by mass

Barium titanate (HPBT-1 manufactured by Fuji Titanium Co., Ltd.) 50% by mass

Polyvinyl butyral (Srec BH-3 manufactured by Sekisui Chemicals) 5% by mass

Next, the dried slurry was applied to the release surface of the release film sample to a thickness of 0.5 ㎛ using an applicator. After drying at 90°C for 1 minute, the slurry surface and the smoothed coating layer surface were overlapped, and a weight of 1 kg/cm2 was applied for 10 minutes. After addition, the release film was peeled off to obtain a ceramic green sheet.

Light is struck from the opposite side of the surface coated with the ceramic slurry in a range of 25 cm2 in the central region of the film width direction of the obtained ceramic green sheet, the occurrence of pinholes visible through the light is observed, and judgment is made by visual observation based on the following criteria. did.

○: No pinholes, no particular problems with thickness variation.

×: Pinholes occur slightly and/or thickness fluctuations are slightly noticeable.

××: Pinholes occur slightly, and thickness fluctuations are slightly noticeable.

×××: There are many occurrences of pinholes, and the thickness fluctuation is greatly noticeable.

(Manufacture of polyethylene terephthalate pellets (PET(I)))

As the esterification reaction device, a continuous esterification reaction device consisting of a three-stage complete mixing tank having a stirring device, a decondenser, a raw material inlet, and a product outlet was used. TPA (terephthalic acid) is set at 2 tons/hour, EG (ethylene glycol) is set at 2 moles per 1 mole of TPA, antimony trioxide is set at an amount such that the Sb atom is 160 ppm relative to the produced PET, and these slurries are sent to an esterification reaction device. was continuously supplied to the first esterification reaction can and reacted at 255°C with an average residence time of 4 hours at normal pressure. Next, the reaction product in the first esterification reaction can is continuously taken out of the system and supplied to the second esterification reaction can, and the EG distilled off from the first esterification reaction can is fed into the produced PET in the second esterification reaction can. An EG solution containing 8% by mass of magnesium acetate tetrahydrate in an amount such that the Mg atom is 65 ppm relative to the produced PET, and TMPA (trimethyl phosphate) in an amount such that the P atom is 40 ppm relative to the produced PET are supplied. EG solution was added, and reaction was carried out at 260°C with an average residence time of 1 hour at normal pressure. Next, the reaction product from the second esterification reaction can is continuously taken out of the system and supplied to the third esterification reaction can, and averaged at a pressure of 39 MPa (400 kg/cm2) using a high pressure disperser (manufactured by Nippon Seiki Co., Ltd.). 0.2% by mass of porous colloidal silica with an average particle size of 0.9㎛, which was subjected to dispersion treatment for the number of passes of 5, and 0.4% by mass of synthetic calcium carbonate with an average particle size of 0.6㎛ made by attaching 1% by mass of ammonium salt of polyacrylic acid per calcium carbonate, Each was added as a 10% EG slurry and reacted at 260°C with an average residence time of 0.5 hours at normal pressure. The esterification reaction product generated in the third esterification reaction can is continuously supplied to a three-stage continuous polycondensation reaction device to perform polycondensation, and filtered through a filter made of sintered stainless steel fibers with a 95% cut diameter of 20 μm. After performing, ultrafiltration was performed and extruded into water, and after cooling, it was cut into chip shapes to obtain PET chips with an intrinsic viscosity of 0.60 dl/g (hereinafter abbreviated as PET(I)). The lubricant content in the PET chip was 0.6 mass%.

(Manufacture of polyethylene terephthalate pellets (PET(II)))

Meanwhile, in the production of the PET chip, a PET chip with an intrinsic viscosity of 0.62 dl/g completely free of particles such as calcium carbonate and silica was obtained (hereinafter abbreviated as PET(II)).

(Manufacture of laminated film Z)

After drying these PET chips, they are melted at 285°C, melted at 290°C by a separate melt extruder, a filter made of sintered stainless steel fibers with a 95% cut diameter of 15 μm, and a filter with a 95% cut diameter of 15 μm. Filtration is performed in two stages using filters made of sintered stainless steel particles, and they are combined in a feed block, and PET(I) is laminated as a semi-profile side layer and PET(II) as a release-side layer, and the sheets are formed for 45 m. It was extruded (cast) at a speed of 1/min, electrostatically adhered and cooled on a casting drum at 30°C using an electrostatic adhesion method to obtain an unstretched polyethylene terephthalate sheet with an intrinsic viscosity of 0.59 dl/g. The layer ratio was adjusted to PET(I)/PET(II)=60%/40% by calculating the discharge amount of each extruder. Next, this unstretched sheet was heated with an infrared heater, and then stretched 3.5 times in the longitudinal direction at a roll temperature of 80°C using a speed difference between the rolls. After that, it was guided to a tenter and stretched 4.2 times in the transverse direction at 140°C. Next, heat treatment was performed at 210°C in a heat setting zone. After that, a 2.3% relaxation treatment was performed at 170°C in the transverse direction to obtain a biaxially stretched polyethylene terephthalate film Z with a thickness of 31 μm. The Sa of the release side layer of the obtained laminated film Z was 2 nm, and the Sa of the semi-release side layer was 28 nm.

(Polymerization of polyester resin A-1)

In a stainless steel autoclave equipped with a stirrer, thermometer, and partial reflux condenser, 194.2 parts by mass of dimethyl terephthalate, 184.5 parts by mass of dimethyl isophthalate, 14.8 parts by mass of dimethyl-5-sodium sulfoisophthalate, and 185.1 parts by mass of ethylene glycol. , 185.1 parts by mass of neopentyl glycol and 0.2 parts by mass of tetra-n-butyl titanate were added, and transesterification reaction was performed over 4 hours at a temperature of 160°C to 220°C. Next, the temperature was raised to 255°C, the pressure of the reaction system was gradually reduced, and then the reaction was carried out for 1 hour and 30 minutes under reduced pressure of 30 Pa to obtain a copolyester resin (A-1). The obtained copolyester resin (A-1) was light yellow and transparent. The reduced viscosity of the copolyester resin (A-1) was measured and found to be 0.60 dl/g. The glass transition temperature by DSC was 65°C.

(Preparation of polyester water dispersion Aw-1)

30 parts by mass of polyester resin (A-1) and 15 parts by mass of ethylene glycol-n-butyl ether were placed in a reactor equipped with a stirrer, thermometer, and reflux device, and heated and stirred at 110°C to dissolve the resin. After the resin was completely dissolved, 55 parts by mass of water was gradually added to the polyester solution while stirring. After addition, the liquid was cooled to room temperature while stirring, and a milky white polyester aqueous dispersion (Aw-1) with a solid content of 30% by mass was produced.

(Polymerization of polyester resin A-2)

In a stainless steel autoclave equipped with a stirrer, thermometer, and partial reflux cooler, 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 tetra-n- 0.5 parts by mass of butyl titanate was added, and transesterification reaction was performed from 160°C to 220°C over 4 hours.

Next, 14 parts by mass of fumaric acid and 203 parts by mass of sebacic acid were added, the temperature was raised from 200°C to 220°C over 1 hour, and an esterification reaction was performed. Next, the temperature was raised to 255°C, the pressure of the reaction system was gradually reduced, and the reaction was carried out for 1 hour and 30 minutes under reduced pressure of 29 Pa to obtain a hydrophobic copolyester resin (A-2). The obtained hydrophobic copolyester resin (A-2) was light yellow and transparent.

(Preparation of polyester water dispersion Aw-2)

Next, 60 parts by mass of this copolyester resin (A-2), 45 parts by mass of methyl ethyl ketone, and 15 parts by mass of isopropyl alcohol were added to a reactor equipped with a stirrer, thermometer, reflux device, and quantitative dropping device for producing the graft resin. , heated and stirred at 65°C to dissolve the resin. After the resin was completely dissolved, 24 parts by mass of maleic anhydride were added to the polyester solution.

Next, a solution in which 16 parts by mass of styrene and 1.5 parts by mass of azobisdimethyl valeronitrile were dissolved in 19 parts by mass of methyl ethyl ketone was added dropwise to the polyester solution at 0.1 ml/min, and stirring was continued for an additional 2 hours. After sampling for analysis was performed from the reaction solution, 8 parts by mass of methanol was added. Next, 300 parts by mass of water and 24 parts by mass of triethylamine were added to the reaction solution, and stirred for 1 hour.

Afterwards, the internal temperature of the reactor was raised to 100°C, methyl ethyl ketone, isopropyl alcohol, and excess triethylamine were distilled off to obtain a light yellow transparent polyester resin with a uniform solid content concentration of 25% by mass. A water-dispersible polyester-based graft copolymer dispersion (Aw-2) was prepared. The glass transition temperature of the obtained polyester graft copolymer was 68°C.

(Preparation of polyurethane water dispersion Aw-3)

In a four-necked flask equipped with a stirrer, Dimroth cooler, nitrogen introduction tube, silica gel drying tube, and thermometer, 43.75 parts by mass of 4,4-dicyclohexylmethane diisocyanate, 12.85 parts by mass of dimethylolbutanoic acid, and poly with a number average molecular weight of 2000 were added. 153.41 parts by mass of hexamethylene carbonate diol, 0.03 parts by mass of dibutyltin dilaurate, and 84.00 parts by mass of acetone as a solvent were added, and stirred at 75°C for 3 hours in a nitrogen atmosphere until the reaction solution reached the predetermined amine equivalent weight. confirmed. Next, after cooling the reaction liquid to 40°C, 8.77 parts by mass of triethylamine was added to obtain a polyurethane prepolymer solution. Next, 450 g of water was added to a reaction vessel equipped with a homodisper capable of high-speed stirring, the temperature was adjusted to 25°C, and the polyurethane prepolymer solution was added and water-dispersed while stirring and mixing at 2000 min ^-1 . Afterwards, a part of acetone and water was removed under reduced pressure to prepare a water-soluble polyurethane resin solution Aw-3 with a solid content of 37% by mass. The glass transition point temperature of the obtained polyurethane resin was -30°C.

(Silica particle B-1)

Colloidal silica (made by Nissan Chemical Industries, brand name Snotex OL, average particle diameter 40 nm, solid content concentration 20 mass%)

(Silica particles B-2)

Colloidal silica (made by Nissan Chemical Industries, brand name Snotex ZL, average particle size 100 nm, solid content concentration 40 mass%)

(Silica particles B-3)

Colloidal silica (made by Nissan Chemical Industries, brand name MP2040, average particle size 200 nm, solid content concentration 40 mass%)

(Silica particles B-4)

Colloidal silica (made by Nissan Chemical Industries, brand name MP4540M, average particle diameter 450 nm, solid content concentration 40 mass%)

(Acrylic particles B-5)

Acrylic particle water dispersion (made by Nippon Shokubai, brand name MX100W, average particle diameter 150 nm, solid content concentration 10 mass%)

(Mold release agent solution X-1)

100 parts by mass of UV curable silicone resin (UV9300 manufactured by Momentive, solid content concentration 100% by mass) and 1 part by mass of curing catalyst bis(alkylphenyl)iodonium hexafluoroantimonate, toluene/methylethylketone/heptane (=3 :5:2) solution to prepare a release agent solution with a solid content of 2% by mass.

(Mold release agent solution X-2)

100 parts by mass of a thermosetting aminoalkyd resin (Tespine 314, manufactured by Hitachi Chemical Industries, Ltd., 60% by mass of solids) and 1.2 parts by mass of p-toluenesulfonic acid (Dryer 900, manufactured by Hitachi Chemical Industries, Ltd., 50% by mass of solids) as a curing catalyst, It was diluted with a toluene/methyl ethyl ketone/heptane (=3:5:2) solution to prepare a mold release agent solution with a solid content of 2% by mass.

(Back smoothing coating solution Y)

94 parts by mass of dipentaerythritol hexaacrylate [solid content 100% by mass] as an active energy ray compound, and polydimethylsiloxane having a polyether-modified acryloyl group as a polyorganosiloxane (manufactured by Big Chemi Japan Co., Ltd.) , brand name “BYK-3500”, solid content: 100 mass%], 1 part by mass, and as a photopolymerization initiator, an α-aminoalkylphenone-based photopolymerization initiator [manufactured by BASF, brand name “IRGACURE907”, 2-methyl-1[4-(methylthio) )Phenyl]-2-morpholinopropan-1-one, solid content: 100% by mass] 5 parts by mass was diluted with an isopropyl alcohol/methyl ethyl ketone mixed solvent (mass ratio 3/1) to smooth the back surface with a solid content of 20% by mass. Materials for forming a coating layer were obtained.

(Example 1)

(Adjustment of Leehwal Coating Liquid 1)

The lubrication coating liquid 1 of the following composition was prepared.

(Lee Hwal application liquid 1)

water 48.33 parts by mass

isopropyl alcohol 35.00 parts by mass

Polyester water dispersion Aw-1 15.78 parts by mass

(Solid content concentration 30% by mass)

Silica particles B-3 0.59 parts by mass

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

Surfactant (fluorine-based, solids concentration 10% by mass) 0.30 parts by mass

(Manufacture of polyester film)

As a film raw material polymer, PET resin pellets (PET(II)) with an intrinsic viscosity (solvent: phenol/tetrachloroethane = 60/40) of 0.62 dl/g and substantially free of particles were manufactured under reduced pressure of 133 Pa. , and dried at 135°C for 6 hours. After that, it was supplied to an extruder, melt-extruded into a sheet form at about 280°C, and rapidly cooled and tightly solidified on a rotary cooling metal roll maintained at a surface temperature of 20°C to obtain an unstretched PET sheet.

This unstretched PET sheet was heated to 100°C with a heated roll group and an infrared heater, and then stretched 3.5 times in the longitudinal direction with a roll group with a difference in peripheral speed, to obtain a uniaxially stretched PET film.

Next, the lubricant coating solution was applied to one side of the PET film using a bar coater and dried at 80°C for 15 seconds. Additionally, the application amount after final stretching and drying was adjusted to be 0.1 μm. Subsequently, the film was stretched 4.0 times in the width direction at 150°C with a tenter, heated at 230°C for 0.5 seconds while fixing the length of the film in the width direction, and further subjected to a 3% relaxation treatment in the width direction at 230°C for 10 seconds. was performed to obtain an in-line coating polyester film with a thickness of 31㎛.

(Formation of release coating layer)

The mold release agent solution After drying for a few seconds, ultraviolet ray irradiation (300 mJ/cm2) was immediately performed using an electrodeless lamp (H Valve manufactured by Fusion Co., Ltd.) to form a release coating layer to obtain a release film for producing ultra-thin ceramic green sheets. In addition, winding properties, process passability, and handling properties were excellent without any particular problems.

(Example 2)

The same as Example 1 except that the silica particle B-3 in the lubricity coating liquid 1 used in Example 1 was changed to silica particle B-4 (average particle diameter 450 nm, solid content concentration 40 mass%), and the lubricity coating liquid 2 was used. Thus, a release film for manufacturing ultra-thin ceramic green sheets was obtained.

(Example 3)

A release film for producing an ultra-thin layer ceramic green sheet was obtained in the same manner as in Example 1, except that the lubricity coating liquid 1 was changed to the lubrication coating liquid 3 below.

(Lee Hwal application liquid 3)

water 47.43 parts by mass

isopropyl alcohol 35.00 parts by mass

Polyester water dispersion Aw-1 14.92 parts by mass

(Solid content concentration 30% by mass)

Silica particles B-1 2.24 parts by mass

(Average particle diameter 40 nm, solid content concentration 20 mass%)

Silica particles B-4 0.11 parts by mass

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

Surfactant (fluorine-based, solids concentration 10% by mass) 0.30 parts by mass

(Example 4)

A polyester film was obtained in the same manner as in Example 1, except that the lubricant coating liquid 1 was changed to the lubricant coating liquid 4 below.

(Lee Hwal application liquid 4)

water 48.54 parts by mass

isopropyl alcohol 35.00 parts by mass

Polyester water dispersion Aw-1 14.92 parts by mass

(Solid content concentration 30% by mass)

Silica particles B-2 1.12 parts by mass

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

Silica particles B-4 0.11 parts by mass

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

Surfactant (fluorine-based, solids concentration 10% by mass) 0.30 parts by mass

(Example 5)

A polyester film was obtained in the same manner as in Example 1, except that the lubricant coating liquid 1 was changed to the lubricant coating liquid 5 below.

(Lee Hwal Coating Liquid 5)

water 45.18 parts by mass

isopropyl alcohol 35.00 parts by mass

Polyester water dispersion Aw-2 18.93 parts by mass

(Solid content concentration 25% by mass)

Silica particles B-3 0.59 parts by mass

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

Surfactant (fluorine-based, solids concentration 10% by mass) 0.30 parts by mass

(Example 6)

A polyester film was obtained in the same manner as in Example 1, except that the lubricant coating liquid 1 was changed to the lubricant coating liquid 6 below.

(Lee Hwal Coating Liquid 6)

water 51.32 parts by mass

isopropyl alcohol 35.00 parts by mass

Polyurethane resin water dispersion Aw-3 12.79 parts by mass

(Solid content concentration 37% by mass)

Silica particles B-3 0.59 parts by mass

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

Surfactant (fluorine-based, solids concentration 10% by mass) 0.30 parts by mass

(Example 7)

A release film for producing an ultra-thin layer ceramic green sheet was obtained in the same manner as in Example 1, except that the release coating layer was formed as follows.

(Formation of release coating layer)

Release agent solution By doing so, a release coating layer was formed and a release film for manufacturing ultra-thin ceramic green sheets was obtained.

(Example 8)

A polyester film was obtained in the same manner as in Example 1, except that the lubricant coating liquid 1 was changed to the lubricant coating liquid 8 below.

(Lee Hwal application liquid 8)

water 46.56 parts by mass

isopropyl alcohol 35.00 parts by mass

Polyester water dispersion Aw-1 15.78 parts by mass

(Solid content concentration 30% by mass)

Acrylic particles B-5 2.37 parts by mass

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

Surfactant (fluorine-based, solids concentration 10% by mass) 0.30 parts by mass

(Comparative Example 1)

As a film forming a release coating layer, the same as in Example 1 was used instead of the in-line coating film having a release coating layer on one surface produced in Example 1, except that E5000-25㎛ (manufactured by Toyobo) was used. A release film for manufacturing ceramic green sheets was obtained using this method. E5000 contained particles inside the film, and Sa on both surfaces was 0.031㎛.

(Comparative Example 2)

A release film for producing a ceramic green sheet was obtained in the same manner as in Comparative Example 1, except that the application thickness of the release layer was changed to 1.0 μm.

(Comparative Example 3)

As a film forming a release coating layer, instead of the in-line coating film having a lubricant coating layer on one surface produced in Example 1, laminated film Z was used, and the side that did not contain the lubricant of film Z was used. A release film for manufacturing a ceramic green sheet was obtained in the same manner as in Example 1, except that a release coating layer was formed on the surface.

(Comparative Example 4)

The back smoothing coating solution Y was applied to the surface of the release film for producing a ceramic green sheet obtained in Comparative Example 3, opposite to the surface on which the release coating layer was formed, with a reverse gravure coater to a thickness of 0.5 ㎛ after drying, and then 90 After drying with hot air at a temperature of

(Comparative Example 5)

A release film for producing a ceramic green sheet was obtained in the same manner as in Comparative Example 4, except that the back smoothing layer was applied to 0.7 μm.

(Comparative Example 6)

A release film for producing a ceramic green sheet was obtained in the same manner as in Comparative Example 4, except that the back smoothing layer was applied to 1.0 μm.

The evaluation results of each example and comparative example are shown in Table 1. In addition, the winding properties, process passability, and handling properties of each example were excellent, without any particular problems, as in Example 1.

In Examples 1 to 8, since all parameters of Sa, P, and RSm on the surface of the lubricant coating layer were in appropriate ranges, ceramic green sheets without pinholes were obtained. In Comparative Examples 1 to 3, since all parameters Sa, P, and RSm of the smooth surface were large, the occurrence of pinholes was observed. In Comparative Examples 4 to 6, Sa and P could be obtained in an appropriate range by filling the unevenness of the smooth surface with a smoothing layer, but because RSm was large, it was insufficient to suppress the generation of pinholes. A large RSm means that the spacing between the protrusions is wide and the number of protrusions per unit area is small, and the pressure applied to each protrusion increases, which is believed to have caused the pinhole.

According to the present invention, it is possible to provide a release film for producing ceramic green sheets that can achieve both good winding and prevention of pinholes and partial thickness fluctuations, even when the ceramic green sheets are thinned. Furthermore, by using the release film for producing ceramic green sheets of the present invention, an extremely thin ceramic green sheet can be obtained, and a microscopic ceramic capacitor can be efficiently manufactured.

Claims (7)

It has a polyester film as a base material, and has a lubricating coating layer on one surface of the base material,
The polyester film is a polyester film containing at least one type selected from polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate,
The average length (RSm) of the roughness curve elements of the smooth coating layer is 5㎛ or less,
A coated polyester film wherein the average surface roughness (Sa) of the area of the lubricating coating layer is 1 nm to 25 nm, and the maximum protrusion height (P) is 60 nm to 500 nm. The coated polyester film according to claim 1, wherein the lubricant coating layer contains particles. The coated polyester film according to claim 1, wherein the thickness of the easily lubricated coating layer is 0.001 ㎛ or more and 2 ㎛ or less. The coated polyester film according to any one of claims 1 to 3, which is a film for producing ceramic green sheets. A method for producing a ceramic green sheet using the coated polyester film according to any one of claims 1 to 3. The method of manufacturing a ceramic green sheet according to claim 5, wherein the thickness of the ceramic green sheet to be manufactured is 0.2 ㎛ or more and 2 ㎛ or less. A method of manufacturing a ceramic capacitor employing the method of manufacturing a ceramic green sheet according to claim 5.