KR102244105B1 - Imide resin film production system and imide resin film production method - Google Patents

Abstract

The present invention efficiently manufactures a high-quality imide-based resin film having an excellent porosity. A film forming unit 70 for forming a porous resin film by removing particulates from a fired film obtained by firing a green film containing a resin material and fine particles of polyamic acid, polyimide, polyamideimide or polyamide, and It has a chemical etching unit 40 that dissolves a part.

Description

Imide-based resin film production system and imide-based resin film production method {IMIDE RESIN FILM PRODUCTION SYSTEM AND IMIDE RESIN FILM PRODUCTION METHOD}

The present invention relates to an imide-based resin film production system and an imide-based resin film production method.

A lithium ion battery, which is a type of secondary battery, has a structure in which a separator is disposed between a positive electrode and a negative electrode immersed in an electrolyte solution, and direct electrical contact between the positive electrode and the negative electrode is prevented by the separator. Lithium transition metal oxide is used for the positive electrode, and lithium, carbon (graphite), or the like is used for the negative electrode. During charging, lithium ions move from the positive electrode through the separator to the negative electrode, and during discharge, the lithium ions move from the negative electrode through the separator to the positive electrode. As such a separator, in recent years, it is known to use a separator made of a porous polyimide film having high heat resistance and high safety (see, for example, Patent Document 1).

Japanese Unexamined Patent Application Publication No. 2011-111470

However, the conventional porous polyimide film is not sufficient in terms of the porosity of the porous portion, and there are cases in which the movement of lithium ions is hindered. For this reason, when a porous polyimide film is used as a separator, there is a problem that the internal resistance of the battery becomes high. Moreover, it is not limited to a polyimide film, In an imide-based resin film, a high-quality porous film excellent in porosity has been demanded.

In view of the circumstances described above, an object of the present invention is to provide an imide-based resin film production system and an imide-based resin film production method capable of efficiently producing a high-quality imide-based resin film excellent in opening ratio.

The imide-based resin film production system according to the first aspect of the present invention is a production system for producing a porous imide-based resin film, wherein fine particles are removed from a film containing polyamic acid, polyimide, polyamideimide or polyamide, and fine particles. A film forming unit which is removed to form a porous imide-based resin film, and a chemical etching unit that dissolves a part of the imide-based resin film is provided.

The method for producing an imide-based resin film according to the second aspect of the present invention is a method for producing a porous imide-based resin film, comprising a polyamic acid, polyimide, polyamideimide or polyamide, and fine particles from a film containing the fine particles. And forming a porous imide-based resin film by removing and performing a chemical etching treatment to dissolve a part of the imide-based resin film.

According to an aspect of the present invention, it is possible to efficiently produce a high-quality imide-based resin film having an excellent pore rate.

1 is a diagram showing an example of a manufacturing system according to an embodiment of the present invention.
2 is a diagram showing an example of a film forming unit according to the present embodiment.
3 is a diagram illustrating an example of a nozzle provided in the application unit according to the present embodiment.
4 is a perspective view showing an example of a winding portion according to the present embodiment.
5 is a perspective view showing an example of a firing unit according to the present embodiment.
6 is a perspective view showing an example of a chemical etching unit according to the present embodiment.
7 is a diagram schematically showing an example of a chemical etching unit according to the present embodiment.
8 is a perspective view showing an example of a winding portion according to the present embodiment.
9 is a diagram showing an example of the manufacturing process of the imide-based resin film according to the present embodiment.
10 is a diagram showing an example of a manufacturing system according to a modified example.
11 is a diagram showing an example of a take-up device according to a modified example.
12 is a diagram illustrating an example of a separator according to the embodiment.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described with reference to drawings. Hereinafter, the direction in the drawing will be described using the XYZ coordinate system. In this XYZ coordinate system, the plane parallel to the horizontal plane is taken as the XY plane. One direction parallel to this XY plane is indicated as an X direction, and a direction orthogonal to the X direction is indicated as a Y direction. In addition, the direction perpendicular to the XY plane is indicated as the Z direction. Each of the X-direction, Y-direction, and Z-direction will be described as the direction of the arrow in the drawing is the + direction, and the direction opposite to the direction of the arrow is the-direction.

1 is a diagram showing an example of a manufacturing system SYS. The manufacturing system SYS shown in FIG. 1 manufactures a porous resin film F (porous imide resin film). The manufacturing system (SYS) is a coating unit (10) that forms a non-fired film (FA) by applying a predetermined coating liquid, and a firing unit that forms a fired film (FB) by firing the unfired film (FA). (20), a removal unit 30 that removes fine particles from the fired film (FB) to form a porous resin film (F), a chemical etching unit (40) that removes a part of the porous resin film (F), A control device (not shown) that collectively controls each of the units is provided. Further, the application unit 10, the firing unit 20, and the removal unit 30 constitute a film forming unit 70 for forming a porous resin film F.

The manufacturing system (SYS) is composed of, for example, top and bottom two layers, the application unit 10 is disposed in the second layer portion, the firing unit 20, the removal unit 30, and the chemical etching unit 40 It is placed on the first floor. The firing unit 20, the removal unit 30, and the chemical etching unit 40 disposed on the same layer are, for example, arranged side by side in the Y direction, but are not limited thereto, for example, the X direction or the X direction. They may be arranged side by side in the synthesis direction of the and Y directions.

In addition, the hierarchical structure of the manufacturing system (SYS) and the arrangement of each unit in each layer are not limited to the above, for example, the coating unit 10 and the firing unit 20 are arranged in the second layer, and the removal unit ( 30) and the chemical etching unit 40 may be disposed in the first layer portion. Moreover, all units may be arranged on the same floor. In this case, each unit may be arranged in a row or may be arranged in a plurality of rows. In addition, all units may be arranged in different hierarchies.

In the manufacturing system SYS, the green film FA is formed in a strip shape. On the +Y side of the coating unit 10 (in front of the transport direction of the unbaked film FA), a winding portion 50 for winding up the strip-shaped unbaked film FA in a roll shape is provided. On the -Y side of the firing unit 20 (rear in the conveyance direction of the unfired film FA), a delivery portion 60 for sending out the roll-shaped unfired film FA toward the firing unit 20 is provided. On the +Y side of the chemical etching unit 40 (in front of the transport direction of the porous resin film F), a winding portion 80 for winding up the porous resin film F in a roll shape is provided.

In this way, in the section from the delivery unit 60 to the firing unit 20, the removal unit 30, and the chemical etching unit 40 to the winding unit 80 (the first layer portion), the so-called roll-to- Process by the roll method. Therefore, in this section, each film of the unbaked film FA, the fired film FB, and the porous resin film F is conveyed in a series of states.

[Application liquid]

Here, before describing each unit, a coating liquid used as a raw material for the porous resin film F will be described. The coating liquid contains a predetermined resin material, fine particles, and a solvent. Examples of the predetermined resin material include polyamic acid, polyimide, polyamideimide, or polyamide. As the solvent, an organic solvent capable of dissolving these resin materials is used.

In the present embodiment, as the coating liquid, two types of coating liquids (the first coating liquid and the second coating liquid) having different content rates of fine particles are used. Specifically, the first coating liquid is prepared so that the content rate of the fine particles is higher than that of the second coating liquid. Thereby, the strength and flexibility of the unbaked film FA, the fired film FB, and the porous resin film F can be ensured. Moreover, by providing a layer with a low content of fine particles, it is possible to reduce the manufacturing cost of the porous resin film F.

For example, the first coating liquid contains a resin material and fine particles in a volume ratio of 19:81 to 45:65. Further, the second coating liquid is contained so that the resin material and the fine particles have a volume ratio of 20:80 to 50:50. However, the volume ratio is set so that the content rate of the fine particles in the first coating liquid is higher than the content rate of the fine particles in the second coating solution. In addition, the volume of each resin material is a value obtained by multiplying the mass of each resin material by its specific gravity.

In the above case, when the total volume of the first coating liquid is 100, if the volume of the fine particles is 65 or more, the particles are uniformly dispersed, and if the volume of the fine particles is 81 or less, the particles are dispersed without agglomeration. For this reason, pores can be uniformly formed in the porous resin film F. Further, when the volume ratio of the fine particles is within this range, the peelability at the time of forming the unbaked film FA can be ensured.

When the total volume of the second coating liquid is 100, if the volume of the fine particles is 50 or more, the fine particles are uniformly dispersed, and if the volume of the fine particles is less than 80, the fine particles do not aggregate, and cracks or the like are formed on the surface. Since there is no case, it is possible to stably form the porous resin film F having good electrical properties.

The two types of coating liquids are prepared by mixing, for example, a solvent in which fine particles are dispersed in advance, and polyamic acid, polyimide, polyamideimide, or polyamide in an arbitrary ratio. Further, it may be prepared by polymerizing polyamic acid, polyimide, polyamideimide or polyamide in a solvent in which fine particles are previously dispersed. For example, it can be produced by polymerizing tetracarboxylic dianhydride and diamine in an organic solvent in which fine particles are previously dispersed to obtain polyamic acid, or further imidizing to obtain polyimide.

It is preferable that the viscosity of the coating liquid is finally set to 300 to 2000 cP, more preferably in the range of 400 to 1500 cP, and even more preferably in the range of 600 to 1200 cP. When the viscosity of the coating liquid is within this range, it is possible to uniformly form a film.

In the case of drying fine particles and polyamic acid or polyimide in the coating solution to form an unfired film (FA), when the material of the fine particles is an inorganic material described later, the ratio of fine particles/polyimide is 2 to 6 (mass ratio). As much as possible, fine particles and polyamic acid or polyimide may be mixed. It is more preferable to set it as 3-5 (mass ratio). When the material of the fine particles is an organic material to be described later, the fine particles and polyamic acid or polyimide may be mixed so that the ratio of the fine particles/polyimide is 1 to 3.5 (mass ratio). It is more preferable to set it as 1.2-3 (mass ratio). Moreover, when it is set as the unbaked film (FA), it is good just to mix the microparticles|fine-particles and polyamic acid or polyimide so that the volume ratio of microparticles|fine-particles/polyimide may become 1.5-4.5. It is more preferable to set it as 1.8-3 (volume ratio). When the mass ratio or volume ratio of the fine particles/polyimide is more than the lower limit when the un-formed film (FA) is used, pores of an appropriate density can be obtained as a separator, and if it is less than the upper limit, problems such as an increase in viscosity or cracks in the film may not occur. It can form a film stably. Even when the resin material is made of polyamideimide or polyamide instead of polyamic acid or polyimide, the mass ratio is the same as above.

Hereinafter, each resin material will be described in detail.

<Polyamic acid>

The polyamic acid used in this embodiment can be used without any particular limitation, obtained by polymerizing any tetracarboxylic dianhydride and diamine. Although the amount of tetracarboxylic dianhydride and diamine used is not particularly limited, it is preferable to use 0.50 to 1.50 moles of diamine, more preferably 0.60 to 1.30 moles, and more preferably 0.70 to 1.20 moles of diamine with respect to 1 mole of tetracarboxylic acid dianhydride. It is particularly preferred.

Tetracarboxylic dianhydride can be appropriately selected from tetracarboxylic dianhydrides that have been conventionally used as raw materials for synthesis of polyamic acids. The tetracarboxylic dianhydride may be an aromatic tetracarboxylic dianhydride or an aliphatic tetracarboxylic dianhydride, but from the viewpoint of heat resistance of the resulting polyimide resin, it is preferable to use an aromatic tetracarboxylic dianhydride. Tetracarboxylic dianhydride may be used in combination of two or more.

Suitable specific examples of aromatic tetracarboxylic dianhydride include pyromellitic dianhydride, 1,1-bis(2,3-dicarboxyphenyl)ethane dianhydride, bis(2,3-dicarboxyphenyl)methane dianhydride, and bis(3). ,4-dicarboxyphenyl)methane dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,3,3',4'-biphenyltetracarboxylic dianhydride, 2,2,6 ,6-biphenyltetracarboxylic dianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, 2,2-bis(2,3-dicarboxyphenyl)propane dianhydride, 2,2- Bis(3,4-dicarboxyphenyl)-1,1,1,3,3,3-hexafluoropropane dianhydride, 2,2-bis(2,3-dicarboxyphenyl)-1,1,1 ,3,3,3-hexafluoropropane dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, bis(3,4-dicarboxyphenyl)ether dianhydride, bis(2,3) -Dicarboxyphenyl)ether dianhydride, 2,2',3,3'-benzophenonetetracarboxylic dianhydride, 4,4-(p-phenylenedioxy)diphthalic dianhydride, 4,4-(m-phenyl Rendioxy)diphthalic dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 1,2,3,4-benzenetetracarboxylic dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, 2,3,6,7-anthracene tetracarboxylic dianhydride, 1,2,7,8 -Phenanthrene tetracarboxylic dianhydride, 9,9-bis phthalic anhydride fluorene, 3,3',4,4'-diphenylsulfone tetracarboxylic dianhydride, etc. are mentioned. As aliphatic tetracarboxylic dianhydride, for example, ethylene tetracarboxylic dianhydride, butane tetracarboxylic dianhydride, cyclopentane tetracarboxylic dianhydride, cyclohexane tetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride , 1,2,3,4-cyclohexanetetracarboxylic dianhydride and the like. Among these, 3,3',4,4'-biphenyltetracarboxylic dianhydride and pyromellitic dianhydride are preferable from the viewpoint of price and availability. In addition, these tetracarboxylic dianhydrides may be used alone or in combination of two or more.

The diamine can be appropriately selected from diamines conventionally used as a raw material for synthesis of polyamic acid. Although the diamine may be an aromatic diamine or an aliphatic diamine, an aromatic diamine is preferable from the heat resistance point of the polyimide resin obtained. These diamines may be used in combination of two or more.

Examples of the aromatic diamine include diamino compounds in which one or about 2 to 10 phenyl groups are bonded. Specifically, phenylenediamine and its derivatives, diaminobiphenyl compound and its derivatives, diaminodiphenyl compound and its derivatives, diaminotriphenyl compound and its derivatives, diaminonaphthalene and its derivatives, aminophenylaminoindan and its Derivatives, diaminotetraphenyl compounds and derivatives thereof, diaminohexaphenyl compounds and derivatives thereof, and cardo-type fluorenediamine derivatives.

Phenylenediamine is m-phenylenediamine, p-phenylenediamine, and the like, and the phenylenediamine derivative is a diamine bonded with an alkyl group such as methyl group and ethyl group, such as 2,4-diaminotoluene, 2,4-triphenyl Rendiamine and the like.

In the diaminobiphenyl compound, two aminophenyl groups are bonded to phenyl groups. For example, 4,4'-diaminobiphenyl, 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl, and the like.

In the diaminodiphenyl compound, two aminophenyl groups are bonded to each other through different groups. Bonds are ether bonds, sulfonyl bonds, thioether bonds, bonds by alkylene or derivatives thereof, imino bonds, azo bonds, phosphine oxide bonds, amide bonds, ureylene bonds, and the like. The alkylene bond is one having about 1 to 6 carbon atoms, and the derivative group is one in which at least one of the hydrogen atoms of the alkylene group is substituted with a halogen atom or the like.

Examples of diaminodiphenyl compounds include 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenylsulfone , 3,4'-diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'- Diaminodiphenylmethane, 4,4'-diaminodiphenylsulfide, 3,3'-diaminodiphenylketone, 3,4'-diaminodiphenylketone, 2,2-bis(p-aminophenyl )Propane, 2,2'-bis(p-aminophenyl)hexafluoropropane, 4-methyl-2,4-bis(p-aminophenyl)-1-pentene, 4-methyl-2,4-bis( p-aminophenyl)-2-pentene, iminodianiline, 4-methyl-2,4-bis(p-aminophenyl)pentane, bis(p-aminophenyl)phosphine oxide, 4,4'-diaminoazobenzene , 4,4'-diaminodiphenylurea, 4,4'-diaminodiphenylamide, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene , 1,3-bis(3-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, bis[4-(4-aminophenoxy)phenyl]sulfone, bis[4- (3-aminophenoxy)phenyl]sulfone, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoro Propane and the like.

Among these, p-phenylenediamine, m-phenylenediamine, 2,4-diaminotoluene, and 4,4'-diaminodiphenyl ether are preferable from the viewpoint of price and availability.

In the diaminotriphenyl compound, two aminophenyl groups and one phenylene group are all bonded through different groups, and the other groups are selected the same as those of the diaminodiphenyl compound. Examples of diaminotriphenyl compounds include 1,3-bis(m-aminophenoxy)benzene, 1,3-bis(p-aminophenoxy)benzene, and 1,4-bis(p-aminophenoxy)benzene. Can be lifted.

Examples of diaminonaphthalene include 1,5-diaminonaphthalene and 2,6-diaminonaphthalene.

Examples of the aminophenylaminoindan include 5 or 6-amino-1-(p-aminophenyl)-1,3,3-trimethylindan.

Examples of diaminotetraphenyl compounds include 4,4'-bis(p-aminophenoxy)biphenyl, 2,2'-bis[p-(p'-aminophenoxy)phenyl]propane, 2,2'-bis [p-(p'-aminophenoxy)biphenyl]propane, 2,2'-bis[p-(m-aminophenoxy)phenyl]benzophenone, etc. are mentioned.

Examples of the cardo-type fluorenediamine derivative include 9,9-bisanilinefluorene.

The aliphatic diamine is preferably, for example, about 2 to 15 carbon atoms, and specifically, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, and the like.

Further, the hydrogen atom of these diamines may be a compound substituted with at least one substituent selected from the group such as a halogen atom, a methyl group, a methoxy group, a cyano group, and a phenyl group.

The means for producing the polyamic acid used in the present embodiment is not particularly limited, and for example, a known method such as a method of reacting an acid or a diamine component in an organic solvent can be used.

The reaction of tetracarboxylic dianhydride and diamine is usually carried out in an organic solvent. The organic solvent used for the reaction of tetracarboxylic dianhydride and diamine is not particularly limited as long as it can dissolve tetracarboxylic dianhydride and diamine, and does not react with tetracarboxylic dianhydride and diamine. Organic solvents can be used alone or in combination of two or more.

Examples of organic solvents used in the reaction of tetracarboxylic dianhydride and diamine include N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-diethylacetamide, N,N-dimethylformamide, N Nitrogen-containing polar solvents such as ,N-diethylformamide, N-methylcaprolactam, and N,N,N',N'-tetramethylurea; lactone-based polar solvents such as β-propiolactone, γ-butyrolactone, γ-valerolactone, δ-valerolactone, γ-caprolactone, and ε-caprolactone; Dimethyl sulfoxide; Acetonitrile; Fatty acid esters such as ethyl lactate and butyl lactate; Ethers such as diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dioxane, tetrahydrofuran, methyl cellosolve acetate, and ethyl cellosolve acetate; Phenolic solvents, such as cresols, are mentioned. These organic solvents can be used alone or in combination of two or more. Although there is no particular limitation on the amount of the organic solvent used, it is preferable that the content of the resulting polyamic acid is 5 to 50% by mass.

In these organic solvents, from the solubility of the resulting polyamic acid, N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-diethylacetamide, N,N-dimethylformamide, N Nitrogen-containing polar solvents, such as N-diethylformamide, N-methylcaprolactam, and N,N,N',N'-tetramethylurea, are preferable.

The polymerization temperature is generally -10 to 120°C, preferably 5 to 30°C. The polymerization time varies depending on the composition of the raw material to be used, but is usually 3 to 24 Hr (hours). In addition, the intrinsic viscosity of the organic solvent solution of polyamic acid obtained under such conditions is preferably in the range of 10 to 100,000 cP (centipoise), and even more preferably in the range of 5000 to 70,000 cP.

<Polyimide>

As long as the polyimide used in this embodiment is a soluble polyimide soluble in the organic solvent used in the coating liquid, a known polyimide can be used without being limited to its structure or molecular weight. The polyimide may have a functional group capable of condensation such as a carboxyl group in the side chain or a functional group that promotes a crosslinking reaction or the like during firing.

In order to obtain a polyimide soluble in an organic solvent, the use of a monomer to introduce a flexible bent structure into the main chain, for example, ethylenediamine, hexamethylenediamine, 1,4-diaminocyclohexane, 1,3-diaminocyclo Aliphatic diamines such as hexane and 4,4'-diaminodicyclohexylmethane; Aromatic diamines such as 2-methyl-1,4-phenylenediamine, o-triazine, m-triazine, 3,3'-dimethoxybenzidine, and 4,4'-diaminobenzanilide; Polyoxyalkylenediamines such as polyoxyethylenediamine, polyoxypropylenediamine, and polyoxybutylenediamine; Polysiloxane diamine; 2,3,3',4'-oxydiphthalic anhydride, 3,4,3',4'-oxydiphthalic anhydride, 2,2-bis(4-hydroxyphenyl)propanedibenzoate-3, Use of 3',4,4'-tetracarboxylic dianhydride, etc. is effective. In addition, the use of a monomer having a functional group that improves solubility in an organic solvent, for example 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 2-trifluoromethyl- It is also effective to use a fluorinated diamine such as 1,4-phenylenediamine. Further, in addition to the monomer for improving the solubility of the polyimide, a monomer similar to that in the column of the polyamic acid may be used in combination as long as the solubility is not impaired.

There is no particular limitation on the means for producing the polyimide soluble in the organic solvent used in the present invention, and for example, a known method such as a method of chemically imidating polyamic acid or heat imidization to dissolve it in an organic solvent is used. Can be used. Examples of such polyimide include aliphatic polyimide (all aliphatic polyimide), aromatic polyimide, and the like, and aromatic polyimide is preferable. The aromatic polyimide may be one obtained by thermally or chemically cyclization reaction of a polyamic acid having a repeating unit represented by formula (1), or a polyimide having a repeating unit represented by formula (2) dissolved in a solvent. In the formula, Ar represents an aryl group.

[Tue 1]

[Tue 2]

<Polyamideimide>

The polyamideimide used in the present embodiment can be any known polyamideimide, as long as it is a soluble polyamideimide soluble in the organic solvent used in the coating liquid, without being limited by its structure or molecular weight. The polyamideimide may have a functional group capable of condensation such as a carboxyl group in the side chain or a functional group that promotes a crosslinking reaction or the like during firing.

The polyamideimide used in this embodiment is specifically limited to one obtained by reacting any trimellitic anhydride and diisocyanate, or one obtained by imidizing a precursor polymer obtained by reaction of any reactive derivative of trimellitic anhydride and diamine. Can be used without the case.

Examples of any of the above arbitrary trimex anhydrides and acids or their reactive derivatives include trimellitic anhydride halides such as trimellitic anhydride and trimellitic anhydride chloride, trimellitic anhydride ester, and the like.

As diisocyanate, for example, metaphenylene diisocyanate, p-phenylene diisocyanate, 4,4'-oxybis (phenyl isocyanate), 4,4'-diisocyanate diphenylmethane, bis[4-(4-isocyanate phenoxy) Si)phenyl]sulfone, 2,2'-bis[4-(4-isocyanate phenoxy)phenyl]propane, and the like.

As the diamine, the same ones as those exemplified in the description of the polyamic acid can be mentioned.

<Polyamide>

As the polyamide, a polyamide obtained from a dicarboxylic acid and a diamine is preferable, and an aromatic polyamide is particularly preferable.

Examples of dicarboxylic acids include maleic acid, fumaric acid, itaconic acid, methylmaleic acid, dimethylmaleic acid, phenylmaleic acid, chloromaleic acid, dichloromaleic acid, fluoromaleic acid, phthalic acid, isophthalic acid, terephthalic acid, and diphenic acid. have.

As the diamine, the same ones as those exemplified in the description of the polyamic acid can be mentioned.

<fine particles>

Next, the fine particles will be described. As for the fine particles, those having a high sphericity ratio and a small particle size distribution index are used, for example. Such fine particles are excellent in dispersibility in a liquid, so that they do not aggregate with each other. As the particle diameter (average diameter) of the fine particles, it can be set to about 100 to 2000 nm, for example. By using such fine particles, the pore diameter of the porous resin film F obtained by removing the fine particles in a later step can be made the same. For this reason, the electric field applied to the separator formed by the porous resin film F can be made uniform.

Further, as the material of the fine particles, as long as it is insoluble in the solvent contained in the coating liquid and can be removed from the porous resin film F in a subsequent step, it is not particularly limited and a known material can be employed. Examples of the inorganic material include metal oxides such as silica (silicon dioxide), titanium oxide, and alumina (Al ₂ O _{3 ).} In addition, organic polymer fine particles such as high molecular weight olefin (polypropylene, polyethylene, etc.), polystyrene, epoxy resin, cellulose, polyvinyl alcohol, polyvinyl butyral, polyester, polymethyl methacrylate, polyether, etc. Can be lifted. Moreover, as an example of a fine particle, colloidal silica, such as a (monodisperse) spherical silica particle, calcium carbonate, etc. are mentioned. In this case, the pore diameter of the porous resin film F can be made more uniform.

In addition, the microparticles contained in the first coating liquid and the microparticles contained in the second coating liquid may have the same sphericity rate, particle diameter, material, and the like, or may be different from each other. It is preferable that the fine particles contained in the first coating liquid have a particle size distribution index smaller than or equal to the fine particles contained in the second coating liquid. Alternatively, it is preferable that the fine particles contained in the first coating liquid have a smaller or equal sphericity rate than the fine particles contained in the second coating liquid. In addition, it is preferable that the fine particles contained in the first coating liquid have a smaller particle diameter (average diameter) than the fine particles contained in the second coating liquid, and in particular, the fine particles contained in the first coating liquid are 100 to 1000 nm (more It is preferably 100 to 600 nm), and it is preferable that the fine particles contained in the second coating liquid are 500 to 2000 nm (more preferably 700 to 2000 nm). By using a particle diameter of the fine particles contained in the first coating film smaller than the particle diameter of the fine particles contained in the second coating liquid, the ratio of openings of the pores on the surface of the porous resin film F can be made high and uniform. Further, the strength of the film can be increased compared to the case where the entire porous resin film F is made the particle size of the fine particles contained in the first coating liquid.

In addition, the coating liquid may contain various additives such as a releasing agent, a dispersant, a condensing agent, an imidizing agent, and a surfactant, as needed, in addition to a predetermined resin material, fine particles, and a solvent.

[Application unit]

The coating unit 10 has a conveying unit 11, a first nozzle 12, a second nozzle 13, a drying unit 14, and a peeling unit 15.

The conveyance part 11 has a conveyance base material (substrate) S, a base material delivery roller 11a, support rollers 11b to 11d, a base material take-up roller 11e, and a carry-out roller 11f.

The conveyance base material S is formed in a strip shape. The conveying base material S is sent out from the base material delivery roller 11a, spans over the support rollers 11b-11d so that it may have tension, and is wound up by the base material winding roller 11e. Examples of the material of the conveyance substrate S include polyethylene terephthalate (PET), but the material is not limited thereto, and a metal material such as stainless steel may be used.

Each of the rollers 11a to 11f is formed in a cylindrical shape, for example, and is arranged parallel to the X direction, respectively. In addition, each roller 11a to 11f is not limited to the arrangement parallel to the X direction, and at least one of the rollers 11a to 11f may be arranged inclined with respect to the X direction. For example, each of the rollers 11a to 11f may be disposed parallel to the Z direction and may be disposed so that the height position in the Z direction becomes the same. In this case, the conveying base material S moves along the horizontal plane in a line state with respect to the horizontal plane (XY plane).

The substrate delivery roller 11a is disposed in a state in which the transport substrate S is wound. The support roller 11b is disposed on the -Y side of the substrate delivery roller 11a while being disposed on the +Z side of the substrate delivery roller 11a. Moreover, while the support roller 11c is arrange|positioned on the +Z side of the support roller 11b, it is arrange|positioned to the +Y side rather than the support roller 11b. By the arrangement of these three rollers (substrate delivery roller 11a and support rollers 11b and 11c), the conveyance substrate S is supported by the surface including the -Y side end portion of the support roller 11b.

In addition, the support roller 11d is disposed on the -Z side of the support roller 11c while being disposed on the +Y side of the support roller 11c. In this case, by the arrangement of the three rollers of the support rollers 11b to 11d, the conveyance substrate S is supported by the surface including the +Z side end of the support roller 11c.

Further, the support roller 11d may be disposed at a height position substantially the same as the height position (position in the Z direction) of the support roller 11c. In this case, the conveying base material S is sent from the support roller 11c toward the support roller 11d in a state substantially parallel to the XY plane in the +Y direction.

The base material take-up roller 11e is disposed on the -Z side of the support roller 11d. From the support roller 11d toward the base material take-up roller 11e, the conveyance base material S is sent in the -Z direction. The carry-out roller 11f is disposed on the +Y side and the -Z side of the support roller 11d. The carry-out roller 11f sends the unbaked film FA formed in the drying unit 14 in the +Y direction. This unbaked film FA is carried out to the outside of the coating unit 10 by the carry-out roller 11f.

Further, the rollers 11a to 11f are not limited to a cylindrical shape, and a tapered crown may be formed. In this case, it is effective for correction of the curvature of the rollers 11a to 11f, and the conveying substrate S or the unbaked film FA described later can evenly contact the rollers 11a to 11f. Further, a radial crown may be formed on the rollers 11a to 11f. In this case, it is effective in preventing meandering of the conveyed base material S or the unbaked film FA. Further, a cone-cave-shaped crown (a portion in which the central portion in the X direction is curved in a concave shape) may be formed on the rollers 11a to 11f. In this case, since it becomes possible to convey the conveyed base material S or the unbaked film FA while applying tension in the X direction, it is effective in preventing the occurrence of wrinkles. As described above, the following rollers may also have a crown such as a tapered type, a radial type, or a concave type.

2A is a perspective view showing an example of the first nozzle 12. 1 and 2 (a), the first nozzle 12 is a coating film of the first coating liquid Q1 on the conveying substrate S (hereinafter referred to as the first coating film F1) To form. The first nozzle 12 has a discharge port 12a for discharging the first coating liquid Q1. The discharge port 12a is formed so that, for example, the length direction becomes substantially the same as the dimension of the X direction of the conveyance base material S.

The first nozzle 12 is disposed at the discharge position P1. The discharge position P1 is a position in the -Y direction with respect to the support roller 11b. The first nozzle 12 is disposed so that the discharge port 12a is inclined toward the +Y direction. Accordingly, the discharge port 12a is directed to a portion of the conveying substrate S supported by the -Y side end of the support roller 11b. The 1st nozzle 12 discharges the 1st coating liquid Q1 with respect to this conveyance base material S in the horizontal direction from the discharge port 12a.

2B is a perspective view showing an example of the second nozzle 13. As shown in FIGS. 1 and 2B, the second nozzle 13 superimposes the first coating film F1 on the conveying substrate S, and a coating film of the second coating liquid Q2 (hereinafter, referred to as the first coating film F1). 2 A coating film (referred to as F2) is formed. The second nozzle 13 has a discharge port 13a for discharging the second coating liquid Q2. The discharge port 13a is formed so that, for example, the longitudinal direction becomes substantially the same as the dimension in the X direction of the conveyance substrate S.

The second nozzle 13 is disposed at the discharge position P2. The discharge position P2 is a position in the +Z direction with respect to the support roller 11c. The second nozzle 13 is disposed so that the discharge port 13a faces in the -Z direction. Accordingly, the discharge port 13a is directed to a portion of the conveying substrate S supported by the +Z side end of the support roller 11c. The 2nd nozzle 13 discharges the 2nd coating liquid Q2 with respect to this conveyance base material S in the direction of gravity from the discharge port 13a.

Further, the first nozzle 12 and the second nozzle 13 may be movable in at least one of the X-direction, Y-direction, and Z-direction. Further, the first nozzle 12 and the second nozzle 13 may be provided so as to be rotatable around an axis parallel to the X direction. In addition, the first nozzle 12 and the second nozzle 13 are arranged in a standby position (not shown) when the coating liquid is not discharged, and from the standby position to the above discharge positions (P1, P2) when discharging the coating liquid. You may make each move. Further, a portion for performing the preliminary discharge operation of the first nozzle 12 and the second nozzle 13 may be provided.

The first nozzle 12 and the second nozzle 13 are respectively connected to a coating liquid supply source (not shown) through a connection pipe (not shown) or the like. The first nozzle 12 and the second nozzle 13 are provided with a holding portion (not shown) for holding a predetermined amount of a coating liquid therein, for example. In this case, the first nozzle 12 and the second nozzle 13 may have a temperature control unit that adjusts the temperature of the liquid body held in the holding unit.

The amount of the respective coating liquids derived from the first nozzle 12 or the second nozzle 13 and the thickness of the first coating film F1 or the second coating film F2 are determined by the nozzles and the connection pipes ( Not shown), or the pressure of a pump (not shown) connected to the coating liquid supply source (not shown), the conveying speed, the position of each nozzle or the distance between the conveying substrate S and the nozzle, etc. can be adjusted. The film thickness of the first coating film F1 or the second coating film F2 is, for example, 0.5 μm to 500 μm, respectively.

In the case of using two types of coating liquids (first coating liquid Q1 and second coating liquid Q2) as in the present embodiment, the film of the first coating film F1 by the first coating liquid Q1 It is preferable to adjust the thickness, for example, in the range of 0.5 μm to 10 μm, and the film thickness of the second coating film F2 by the second coating liquid Q2, for example, in the range of 1 μm to 50 μm. Do.

Further, a drying unit (not shown) for drying the first coating film F1 may be disposed between the first nozzle 12 and the second nozzle 13. It is preferable that this drying part is provided with a heat drying part. It is preferable to use a warm air blower or an infrared heater as the heating and drying unit. The heating temperature is, for example, in the range of 50°C to 150°C, preferably 50°C to 100°C. By forming the second coating film F2 after drying the first coating film F1, the occurrence of streak marks on the first coating film F1 can be suppressed.

As shown in FIG. 1, the drying part 14 is the +Y side of the 2nd nozzle 13, and is arrange|positioned between the support roller 11c and the support roller 11d. The drying unit 14 dries the two layers of coating films (first coating film F1 and second coating film F2) applied on the conveying substrate S to form an unfired film FA.

The drying unit 14 has a chamber 14a and a heating unit 14b. The chamber 14a accommodates the conveying substrate S and the heating unit 14b. The heating part 14b heats the 1st coating film F1 and the 2nd coating film F2 formed on the conveyance base material S. As the heating unit 14b, for example, an infrared heater or the like is used. The heating unit 14b heats the coating film at a temperature of about 50°C to 100°C.

The peeling portion 15 is a portion from which the unbaked film FA is peeled from the conveying substrate S. In the present embodiment, the unbaked film FA is peeled off manually by an operator, but it is not limited thereto, and may be performed automatically using a manipulator or the like. The unbaked film FA peeled off from the conveying base material S is carried out to the outside of the coating unit 10 by the take-out roller 11f and sent to the take-up unit 50. Moreover, the conveyed base material S from which the unbaked film FA was peeled off is wound up by the base material winding roller 11e.

[Rewind (1)]

3 is a perspective view schematically showing the configuration of the coating unit 10 on the +Y side.

As shown in FIG. 3, on the +Y side of the coating unit 10, a carrying out port 10b for carrying out the unbaked film FA is provided. The unbaked film FA carried out from the carrying out port 10b is wound up by the take-up part 50.

The winding unit 50 has a configuration in which the shaft member SF is mounted on the bearing 51. The shaft member SF winds up the unbaked film FA carried out from the carrying out port 10b to form a roll body R. The shaft member SF is provided to be detachable from the bearing 51. When the shaft member SF is mounted on the bearing 51, it is supported so as to be rotatable around an axis parallel to the X direction. The winding unit 50 has a drive mechanism (not shown) for rotating the shaft member SF mounted on the bearing 51.

In addition, in the winding unit 50, the unbaked film FA is wound so that the surface on the side of the first coating film F1 of the unbaked film FA is disposed on the outside. For example, by rotating the shaft member SF counterclockwise in FIG. 1 by a drive mechanism, the unbaked film FA is wound up. By separating the shaft member SF from the bearing 51 with the roll body R formed, it becomes possible to move the roll body R to another unit.

In addition, although the winding part 50 is arrange|positioned independently from the coating unit 10 in FIGS. 1 and 3, it is not limited to this. For example, the winding portion 50 may be disposed inside the coating unit 10. In this case, the roll body R may be formed by winding the unbaked film FA from the take-out roller 11f (or from the support roller 11d) without arranging the take-out port 10b in the coating unit 10. do.

[Sending Department]

4 is a perspective view schematically showing the configuration of the firing unit 20 on the -Y side.

As shown in FIG. 4, on the -Y side of the firing unit 20, the carrying-in port 20a through which the unbaked film FA is carried is provided. The delivery unit 60 delivers the unbaked film FA to the delivery port 20a.

The delivery unit 60 has a configuration in which the shaft member SF can be attached to the bearing 61. The shaft member SF can be used in common with mounting on the bearing 51 of the winding unit 50. Accordingly, the shaft member SF removed from the take-up portion 50 can be attached to the bearing 61 of the delivery portion 60. Thereby, the roll body R formed by the winding part 50 can be arrange|positioned in the delivery part 60. In addition, for the bearing 61 and the bearing 51 of the winding part 50, it is possible to set the height from the bottom surface to be the same, but may be set to different height positions.

When the shaft member SF is mounted on the bearing 61, it is supported so as to be rotatable around an axis parallel to the X direction. The delivery unit 60 has a drive mechanism (not shown) that rotates the shaft member SF mounted on the bearing 61. By rotating the shaft member SF by the clockwise rotation of FIG. 1 by the drive mechanism, the unbaked film FA constituting the roll body R is sent out toward the carrying port 20a. Further, in the above winding portion 50, since the unbaked film FA is wound so that the surface of the first coating film F1 side of the unbaked film FA is disposed outside, the unbaked film FA is wound from the roll body R. ) Is taken out, the first coating film F1 side is disposed on the upper side.

[Firing unit]

The firing unit 20 is a unit that performs high-temperature treatment on the unbaked film FA in the present embodiment. The firing unit 20 fires the unfired film FA to form a fired film FB containing fine particles. The firing unit 20 has a chamber 21, a heating section 22, and a conveying section 23. The chamber 21 has a carry-in port 20a for carrying in the unbaked film FA, and an outlet 20b for carrying out the fired film FB. The chamber 21 accommodates the heating section 22 and the conveying section 23.

The heating unit 22 heats the unbaked film FA carried in the chamber 31. The heating unit 22 has a plurality of heaters 22a arranged side by side in the Y direction. As the heater 22a, for example, an infrared heater or the like is used. The heating unit 22 is disposed from the -Y side end to the +Y side end of the chamber 21. The heating unit 22 is configured to be able to heat the unbaked film FA almost entirely in the Y direction. The heating unit 22 can heat the unbaked film FA at about 120°C to 450°C, for example. The heating temperature by the heating unit 22 is appropriately adjusted according to the conveyance speed of the unbaked film FA, the components of the unbaked film FA, and the like.

The conveyance part 23 has a conveyance belt 23a, a drive roller 23b, a driven roller 23c, and tension rollers 23d and 23e. The conveyance belt 23a is formed in an endless shape, and is arrange|positioned along the Y direction. The conveyance belt 23a is formed using a material having durability against the firing temperature of the unbaked film FA. The conveyance belt 23a is stretched between the drive roller 23b and the driven roller 23c so as to be substantially parallel to the XY plane in a state having tension. The unbaked film FA and the fired film FB are conveyed in the +Y direction while being mounted on the conveying belt 23a.

The drive roller 23b is disposed at an end of the chamber 21 on the +Y side. The drive roller 23b is formed in a cylindrical shape, for example, and is arranged parallel to the X direction. The drive roller 23b is provided with a rotation drive device such as a motor, for example. The drive roller 23b is rotatably provided around an axis parallel to the X direction by this rotation drive device. When the drive roller 23b rotates, the conveyance belt 23a rotates clockwise in FIG. 1. By rotating the conveyance belt 23a, the unbaked film FA and the fired film FB placed on the conveying belt 23a are conveyed in the +Y direction.

The driven roller 23c is disposed at an end of the chamber 21 on the -Y side. The driven roller 23c is formed in a cylindrical shape, for example, and is arranged parallel to the X direction. The driven roller 23c is formed to have the same diameter as the drive roller 23b, and is arranged so that the position (height position) in the Z direction is substantially the same as the drive roller 23b. The driven roller 23c is provided so as to be rotatable around an axis line parallel to the X direction. The driven roller 23c rotates following the rotation of the conveyance belt 23a.

The tension roller 23d is arranged on the +Z side of the driven roller 23c. The tension roller 23d is arranged parallel to the X direction, and is provided so as to be rotatable around the X axis. The tension roller 23d is provided to be able to move up and down in the Z direction. The tension roller 23d is capable of sandwiching the unbaked film FA between the driven roller 23c. The tension roller 23d is rotatable with the unsaturated film FA sandwiched therebetween.

The tension roller 23e is arranged on the +Z side of the drive roller 23b. The tension roller 23e is arranged parallel to the X direction, and is provided so as to be rotatable around the X axis. The tension roller 23e is provided so as to be able to move up and down in the Z direction. The tension roller 23e can sandwich the fired film FB between the driving roller 23b. The tension roller 23e is rotatable with the firing film FB sandwiched therebetween.

The tension rollers 23d and 23e are in a state where the unbaked film FA and the fired film FB are respectively sandwiched between the driven roller 23c and the driving roller 23b, Tension from the outside is cut in the portion between the two sandwiched positions in the film formation FB. Thereby, it is possible to prevent an excessive load from being applied to the unbaked film FA and the fired film FB. The tension rollers 23d and 23e can be adjusted so that tension is not applied to the unbaked film FA and the fired film FB disposed in the chamber 21.

[Removal unit]

The removal unit 30 has a chamber 31, an etching part 32, a cleaning part 33, a liquid removal part 34, and a conveyance part 35. The chamber 31 has a carry-in port 30a for carrying in the fired film FB, and an outlet port 30b for carrying out the porous resin film F. The chamber 31 accommodates the etching part 32, the cleaning part 33, the liquid removal part 34, and the conveyance part 35.

The etching part 32 performs etching on the fired film FB to remove particulates contained in the fired film FB to form a porous resin film F. In the etching part 32, the microparticles are removed by immersing the fired film FB in an etching solution capable of dissolving or decomposing microparticles. The etching unit 32 is provided with a supply unit (not shown) for supplying such an etching solution and a storage unit capable of storing the etching solution. Since the liquid contained therein is different between the etching part 32 and the cleaning part 33, you may provide a water supply roller mentioned later at the position immediately before being carried out from the etching part 32. The absorption roller is disposed on at least one, preferably both, on the +Z side and the -Z side with respect to the porous resin film F.

The cleaning unit 33 cleans the porous resin film F after etching. The cleaning unit 33 is disposed on the +Y side of the etching unit 32 (in front of the transport direction of the porous resin film F). The cleaning unit 33 has a supply unit (not shown) for supplying a cleaning liquid. Moreover, you may have a recovery part (not shown) etc. which collect|recovers wastewater after washing|cleaning the porous resin film F.

The liquid removal unit 34 removes the liquid adhering to the porous resin film F after washing. You may perform preliminary drying or the like. The liquid removal unit 34 is disposed on the +Y side of the cleaning unit 33 (in front of the transport direction of the porous resin film F). The liquid removal part 34 is provided with an absorption roller or the like. By bringing the absorption roller into contact with the porous resin film F, it is possible to absorb the liquid adhering to the porous resin film F while transporting the porous resin film F. The arrangement of the absorption roller in the conveyance direction is not particularly limited as long as it is immediately before being carried out from the liquid removal unit 34. In addition, the absorption roller is disposed on at least one, preferably both of the +Z side and -Z side with respect to the porous resin film F.

The conveyance part 35 conveys the fired film FB and the porous resin film F over the etching part 32, the cleaning part 33, and the liquid removal part 34. The conveyance part 35 has a conveyance belt 35a, a drive roller 35b, and a driven roller 35c. In addition to the drive roller 35b and the driven roller 35c, a support roller for supporting the conveyance belt 35a may be disposed inside the etching portion 32, the cleaning portion 33, and the liquid removal portion 34. .

The conveyance belt 35a is formed in an endless shape, and is arrange|positioned along the Y direction. The conveyance belt 35a is formed using a material having durability against the etching solution. The conveyance belt 35a is stretched between the drive roller 35b and the driven roller 35c so as to be substantially parallel to the XY plane in a state having tension. The fired film FB and the porous resin film F are placed on the conveyance belt 35a.

The drive roller 35b is disposed at the end of the chamber 31 on the +Y side. The drive roller 35b is formed in a cylindrical shape, for example, and is arranged parallel to the X direction. The drive roller 35b is provided with a rotation drive device such as a motor, for example. The drive roller 35b is rotatably provided around an axis parallel to the X direction by this rotation drive device. As the drive roller 35b rotates, the conveyance belt 35a rotates clockwise in FIG. 1. When the conveyance belt 35a rotates, the fired film FB and the porous resin film F placed on the conveyance belt 35a are conveyed in the +Y direction.

The driven roller 35c is disposed at the -Y side end of the chamber 31. The driven roller 35c is formed in a cylindrical shape, for example, and is arranged parallel to the X direction. The driven roller 35c is formed with the same diameter as the drive roller 35b, and is arranged so that the position (height position) in the Z direction is substantially the same as the drive roller 35b. The driven roller 35c is provided so as to be rotatable around an axis line parallel to the X direction. The driven roller 35c rotates following the rotation of the conveyance belt 35a.

In addition, the removal unit 30 is not limited to the case where the fine particles are removed by etching. For example, when an organic material that decomposes at a lower temperature than polyimide is used as the material of the fine particles, the fine particles can be decomposed by heating the fired film FB. As such an organic material, as long as it decomposes at a lower temperature than polyimide, it can be used without any particular limitation. For example, resin fine particles made of a linear polymer or a known sea polymerizable polymer can be mentioned. In general linear polymers, molecular chains of the polymer are randomly cut during thermal decomposition, and depolymerizable polymers are polymers in which the polymer is decomposed into monomers during thermal decomposition. All are decomposed to a low molecular weight _{substance or CO 2} , thereby disappearing from the fired film FB. In this case, the decomposition temperature of the fine particles is preferably 200 to 320°C, more preferably 230 to 260°C. When the decomposition temperature is 200° C. or higher, film formation can be performed even when a high boiling point solvent is used for the coating liquid, and the range of selection of firing conditions in the firing unit 20 is widened. Further, when the decomposition temperature is less than 320°C, only fine particles can be eliminated without imparting thermal damage to the fired film FB.

[Chemical Etching Unit]

The chemical etching unit 40 is disposed on the +Y side of the removal unit 30. 6 is a diagram showing an example of the chemical etching unit 40 and the winding unit 80. As shown in Fig. 6, the chemical etching unit 40 includes a chamber 41, a conveyance unit 42, a chemical etching unit 43, a cleaning unit 44, a liquid removing unit 45, and It has a heating part 46. The chamber 41 has a carrying-in port 40a for carrying in the porous resin film F, and a carrying-in port 40b for carrying out the porous resin film F. The chamber 41 accommodates the conveyance part 42, the chemical etching part 43, the cleaning part 44, and the liquid removal part 45.

The conveyance part 42 conveys the porous resin film F in the +Y direction over the chemical etching part 43, the cleaning part 44, and the liquid removal part 45. The conveyance part 42 has the conveyance belt 42a, the drive roller 42b, and the driven rollers 42c-42e. In addition to the drive roller 42b and the driven rollers 42c to 42e, in the chemical etching section 43, the cleaning section 44, and the liquid removing section 45, a support roller supporting the conveyance belt 42a is provided. It may be arranged.

The conveyance belt 42a is formed in an endless shape, and is arrange|positioned along the Y direction. The conveyance belt 42a is formed by using a material having durability against the etching solution EQ described later. The conveyance belt 42a is formed in a mesh shape, for example, and an etching liquid can pass through the conveyance belt 42a. The conveyance belt 42a is stretched between the drive roller 42b and the driven roller 42c in a state having tension so as to be substantially parallel to the XY plane. The porous resin film F is placed on the conveying belt 42a and conveyed.

The drive roller 42b is disposed at an end of the chamber 41 on the +Y side. The drive roller 42b is formed in a cylindrical shape, for example, and is arranged parallel to the X direction. The drive roller 42b is provided with a rotation drive device such as a motor, for example. The drive roller 42b is rotatably provided around an axis parallel to the X direction by this rotation drive device. When the drive roller 42b rotates, the conveyance belt 42a rotates clockwise in FIG. 6. By rotating the conveyance belt 42a, the porous resin film F placed on the conveyance belt 42a is conveyed in the +Y direction.

The driven roller 42c is disposed at the -Y side end of the chamber 41. The driven rollers 42d and 42e are disposed on the -Z side of the driven roller 42c and the drive roller 42b, respectively. The driven rollers 42c to 42e are formed in a cylindrical shape, for example, and are arranged parallel to the X direction. The driven roller 42c is formed to have the same diameter as the drive roller 42b, and is arranged so that the position (height position) in the Z direction becomes substantially the same as the drive roller 42b. The driven roller 42d is formed with the same diameter as the drive roller 42e, and is arranged so that the position (height position) in the Z direction becomes substantially the same as the drive roller 42e. The driven rollers 42c to 42e are provided so as to be rotatable around an axis parallel to the X direction. The driven rollers 42c to 42e rotate following the rotation of the conveyance belt 42a.

The chemical etching part 43 performs chemical etching on the porous resin film F to dissolve a part of the porous resin film F. 7 is a diagram schematically showing an example of the chemical etching portion 43. As shown in FIG. 7, the chemical etching part 43 has an upper nozzle 43a, a lower nozzle 43b, and a roller 43c.

The upper nozzle 43a is disposed on the +Z side of the conveyance belt 42a. A plurality of upper nozzles 43a are arranged side by side in the Y direction, for example. Each upper nozzle 43a has a plurality of discharge ports 43d in the X direction. Each discharge port 43d faces the -Z side. From each discharge port 43d, the spray-like etching liquid EQ is discharged in the -Z direction. A supply source (not shown) of the etching liquid EQ is connected to each of the upper nozzles 43a.

The lower nozzle 43b is disposed on the -Z side of the conveyance belt 42a. A plurality of lower nozzles 43b are arranged side by side in the Y direction, for example. 7 shows a state in which the upper nozzles 43a and the lower nozzles 43b are alternately parallel in the Y direction, but the arrangement is not limited thereto. Each lower nozzle 43b has a plurality of discharge ports 43e in the X direction. From each discharge port 43e, the spray-like etching liquid EQ is discharged in the +Z direction. A supply source (not shown) of the etching liquid EQ is connected to each of the lower nozzles 43b.

Each of the rollers 43c is disposed at the +Y side end and the -Y side end of the chemical etching portion 43, for example. The roller 43c can hold the porous resin film F between the conveyance belt 42a. Further, the roller 43c is rotatable in accordance with the rotation of the conveyance belt 42a.

Further, the chemical etching unit 43 may have a recovery unit (not shown) or the like for recovering wastewater from the etching solution EQ. Moreover, the chemical etching part 43 may have an exhaust part (not shown) etc. which exhausts the inside.

In the chemical etching part 43, when the two rollers 43c are in contact with the porous resin film F together, when the etchant EQ is discharged from the upper nozzle 43a, the etchant EQ is It becomes easy to gather in the section between the two rollers 43c. By continuously discharging the etchant EQ from the upper nozzle 43a, a storage unit 47 in which the etchant EQ is stored is formed in this section. Moreover, the etching liquid EQ ejected from the lower nozzle 43b passes through the mesh of the conveyance belt 42a and reaches the surface of the -Z side of the porous resin film F. The etching solution EQ reaching the -Z side of the porous resin film F pushes up the porous resin film F in the +Z direction. In this case, the etching liquid EQ ejected from the lower nozzle 43b is disposed between the pushed-up porous resin film F and the conveyance belt 42a. Accordingly, the porous resin film F is immersed in an apparently floating state in the etching solution EQ stored in the storage unit 47, and a chemical etching treatment is performed in this state. In this way, the transport unit 42 immerses the porous resin film F in the etching solution EQ in the storage unit 47.

In addition, as the etching solution (EQ), for example, an inorganic alkali solution or an organic alkali solution is used. Examples of the inorganic alkali solution include a hydrazine solution containing hydrazine hydrate and ethylenediamine, a solution of alkali metal hydroxides such as potassium hydroxide, sodium hydroxide, sodium carbonate, sodium silicate, and sodium metasilicate, ammonia solution, alkali hydroxide, and hydrazine. , An etching solution containing 1,3-dimethyl-2-imidazolidinone as a main component, and the like. Examples of the organic alkali solution include primary amines such as ethylamine and n-propylamine; Secondary amines such as diethylamine and di-n-butylamine; Tertiary amines such as triethylamine and methyldiethylamine; Alcohol amines such as dimethylethanolamine and triethanolamine; Quaternary ammonium salts such as tetramethylammonium hydroxide and tetraethylammonium hydroxide; And alkaline solutions such as cyclic amines such as pyrrole and piperidine. Further, for the solvent of each of the above solutions, pure water and alcohols can be appropriately selected. Moreover, what added a surfactant in an appropriate amount can also be used. The alkali concentration is, for example, 0.01 to 20% by mass.

Moreover, as another aspect of the chemical etching part 43, the structure which has the upper nozzle 43a, the roller 43c, and the bottom member (not shown) may be sufficient. Further, in this embodiment, the configuration of each portion of the upper nozzle 43a and the roller 43c is the same as that of the above embodiment, and thus description is omitted. The bottom member of the chemical etching part 43 according to this aspect is provided on the -Z side of the mesh of the conveyance belt 42a and is formed along the XY plane. This bottom member is disposed to face the conveyance belt 42a. The bottom member may or may not contact the conveyance belt 42a. When the bottom member is disposed so as to be in contact with the conveyance belt 42a, the storage portion 47 capable of storing the etching liquid EQ is formed in a section between the two rollers 43c. Further, even when the bottom member is disposed so as not to contact the conveyance belt 42a, the storage portion 47 can be formed. In this case, the conveyance belt 42a contacts the two rollers 43c and the bottom member, for example, by putting the mesh of the conveyance belt 42a in the bottom member and the bottom member of the two rollers 43c. For this reason, the etching liquid EQ can be stored in the section between the two rollers 43c, and the storage part 47 is formed. With such a bottom member, it becomes easier to form the storage part 47 of the etching liquid EQ in the section between the two rollers 43c with respect to the Y direction. For this reason, it becomes easy to maintain the state in which the porous resin film F is immersed in the etching solution EQ stored in the storage unit 47. As the material of the floor member, a material having durability may be appropriately selected according to the type or concentration of the etching solution EQ, such as the conveyance belt 42a, and is formed using, for example, vinyl chloride. Further, a plurality of holes penetrating in the Z direction may be provided in the bottom member. Thereby, the etchant EQ can be supplied to the storage unit 47 from the supply source of the etchant EQ through the hole in the bottom member. When providing the hole of the bottom member, it is not necessary to provide the upper nozzle 43a.

Next, as shown in FIG. 6, the cleaning unit 44 cleans the porous resin film F after chemical etching. The cleaning unit 44 is disposed on the +Y side of the chemical etching unit 43 (in front of the transport direction of the porous resin film F). The cleaning unit 44 has a supply unit (not shown) for supplying a cleaning liquid. Moreover, you may have a recovery part (not shown) etc. which collect|recovers wastewater after washing|cleaning the porous resin film F. Since the liquid contained therein is different between the chemical etching unit 43 and the cleaning unit 44, the above-described water supply roller may be provided at a position immediately before being carried out from the chemical etching unit 43. The absorption roller is disposed on at least one, preferably both, on the +Z side and the -Z side with respect to the porous resin film F.

The liquid removal unit 45 removes the liquid adhering to the porous resin film F after cleaning. You may perform preliminary drying or the like. The liquid removal unit 45 is disposed on the +Y side of the cleaning unit 44 (in front of the transport direction of the porous resin film F). The liquid removal part 45 is provided with an absorption roller or the like. By bringing the absorption roller into contact with the porous resin film F, it is possible to absorb the liquid adhering to the porous resin film F while transporting the porous resin film F. The arrangement of the absorption roller in the conveyance direction is not particularly limited as long as it is immediately before being carried out from the liquid removal unit 34.

The heating unit 46 is disposed on the +Y side of the chamber 41 (in front of the transport direction of the porous resin film F). The heating part 46 heats the porous resin film F after liquid removal by the liquid removal part 45 at about 100 degreeC-300 degreeC, and performs a drying process or a post-baking process. The heating unit 46 is provided with a heating unit or the like for heating the porous resin film F. On the +Y side of the heating part 46, a carrying out port 46b for carrying out the porous resin film F is provided.

[Winding part (2)]

8 is a perspective view schematically showing the configuration of the chemical etching unit 40 on the +Y side.

As shown in FIG. 8, on the +Y side of the chemical etching unit 40, a carrying out port 46b for carrying out the porous resin film F is provided. The porous resin film F carried out from the carrying out port 46b is wound up by the winding unit 80.

The winding unit 80 has a configuration in which the shaft member SF is attached to the bearing 81. The shaft member SF forms a roll body RF by winding the porous resin film F carried out from the carrying out port 40b. The shaft member SF is provided to be detachable from the bearing 81. When the shaft member SF is mounted on the bearing 81, it is supported so as to be rotatable around an axis parallel to the X direction. The winding unit 80 has a drive mechanism (not shown) for rotating the shaft member SF mounted on the bearing 81. By rotating the shaft member SF by a drive mechanism, the porous resin film F is wound up. By separating the shaft member SF from the bearing 81 with the roll body RF formed, it becomes possible to recover the roll body RF.

[Manufacturing method]

Next, an example of an operation of manufacturing the porous resin film F using the manufacturing system SYS configured as described above will be described. 9A to 9F are views showing an example of a manufacturing process of the porous resin film F.

First, in the application unit 10, an unbaked film FA is formed. In the coating unit 10, the substrate delivery roller 11a is rotated to deliver the conveyed substrate S, and the conveyed substrate S is mounted on the support rollers 11b to 11d, and then wound up with the substrate take-up roller 11e. . Thereafter, winding is performed with the substrate take-up roller 11e while sequentially sending the conveyed substrates S from the substrate delivery roller 11a.

In this state, the first nozzle 12 is disposed at the first position P1, and the discharge port 12a is directed in the +Y direction. Thereby, the discharge port 12a is directed to the portion of the conveying substrate S supported by the support roller 11b. After that, the first coating liquid Q1 is discharged from the discharge port 12a. After the first coating liquid Q1 is discharged from the discharge port 12a toward the +Y direction and reaches the conveying base material S, it is applied onto the conveying base material S in accordance with the movement of the conveying base material S. Thereby, the 1st coating film F1 by the 1st coating liquid Q1 is formed on the conveyance base material S.

Next, the second nozzle 12 is disposed at the second position P2, so that the discharge port 13a is directed in the -Z direction. Thereby, the discharge port 13a is directed to the portion of the conveying substrate S supported by the support roller 11c. After that, the second coating liquid Q2 is discharged from the discharge port 13a. After the second coating liquid Q2 is discharged from the discharge port 13a toward the -Z direction and reaches the first coating film F1 formed on the conveying substrate S, the first coating liquid Q2 is moved according to the movement of the conveying substrate S. It is applied on the coating film F1. Thereby, as shown in FIG. 9A, the 2nd coating film F2 by the 2nd coating liquid is formed on the 1st coating film F1. Further, in the first coating film F1 and the second coating film F2, the fine particles A2 are contained in the resin material A1 in different volume ratios. In addition, the content rate of the fine particles is set larger in the first coating film F1 than in the second coating film F2.

In addition, the first coating liquid (Q1) and the second coating liquid (Q2) are applied to the portion of the conveying substrate (S) supported by the support rollers (11b, 11c) with the discharge ports (12a) and (13a) facing. Therefore, when the 1st coating liquid Q1 and the 2nd coating liquid Q2 reach the conveyance base material S, the force acting on the conveyance base material S is received by the support rollers 11b, 11c. For this reason, generation|occurrence|production of warpage, vibration, etc. of the conveyance base material S is suppressed, and the 1st coating film F1 and the 2nd coating film F2 are formed on the conveyance base material S stably with a uniform thickness.

Subsequently, when the conveying base material S moves and the laminated part of the 1st coating film F1 and the 2nd coating film F2 is carried into the chamber 14a of the drying part 14, in the drying part 14 The first coating film F1 and the second coating film F2 are dried. In the drying part 14, the heating part 14b is used, and the 1st coating film F1 and the 2nd coating film F2 are heated at a temperature of, for example, about 50°C to 100°C. If it is this temperature range, the 1st coating film F1 and the 2nd coating film F2 can be heated without a case where distortion, deformation, etc. occur in the conveyance base material S. By drying the laminated body of the first coating film F1 and the second coating film F2, as shown in Fig. 9B, an unbaked film FA is formed.

In addition, in the present specification, the layered product refers to an unbaked film formed of the first coating film F1 and the second coating film F2. When forming the porous imide-based resin film according to the present invention, in the first liquid and the second liquid, when the same type of resin is used among polyamic acid, polyimide, polyamideimide, or polyamide, the first formed The unbaked film (or porous imide resin film) composed of the coating film (F1) and the second coating film (F2) becomes substantially one layer, but the unfired film (or regions having different porosities) with a different content of fine particles. Since a porous imide resin film) is formed, the present specification is referred to as a laminated body including the case where the same type of resin is used for the first liquid and the second liquid.

Subsequently, when the conveying base material S moves and the tip part of the unbaked film FA reaches the support roller 11d (the peeling part 15), for example, by manual operation of an operator, this The tip portion is peeled from the conveying substrate S. In the present embodiment, since PET is used as the material of the conveyance substrate S, for example, when the first coating film F1 and the second coating film F2 are dried to form an unfired film FA , Since it becomes easy to peel off from the conveyance base material S, an operator can perform peeling easily.

After peeling off the tip portion of the unbaked film FA, the conveying substrate S continues to move, and the first coating film F1 is formed by the first nozzle 12. Further, the second coating film F2 is continuously formed by the second nozzle 13, and the unbaked film FA is formed by the drying unit 14. Thereby, the unbaked film FA is formed in a strip shape, and the length of the unbaked film FA carried out from the drying part 14 to the +Y side gradually increases. The operator continuously peels the unbaked film FA from the peeling part 15. And, when the tip end of the peeled green film FA has reached the shaft member SF of the take-up unit 50, the operator manually hooks the green film FA on the take-out roller 11f. , Attaching the tip portion of the unbaked film FA to the shaft member SF. Thereafter, as the unbaked film FA is sequentially formed and peeled off, the shaft member SF is rotated in the winding unit 50. Thereby, the peeled unbaked film FA is sequentially carried out from the coating unit 10 and wound up by the shaft member SF of the winding unit 50 to form the roll body R. The unbaked film FA constituting the roll body R is in a state of being peeled off from the conveying substrate S, as shown in Fig. 9C, and the front and back surfaces are exposed together.

In addition, the operation of peeling off the tip portion of the unformed film FA, and attaching the peeled tip portion to the shaft member SF are not limited to the manner performed by the operator by hand, for example, a manipulator or the like is used. It may be carried out automatically. Moreover, in order to improve the peelability of the unbaked film FA, a release layer may be formed on the surface of the conveying substrate S.

After the green film FA of a predetermined length is wound around the shaft member SF, the shaft member SF is separated from the bearing 51 for each roll body R while cutting the green film FA. Then, a new shaft member SF is attached to the bearing 51 of the winding portion 50, and the cut-off end of the unbaked film FA is attached to the shaft member SF and rotated, thereby forming the unbaked film FA. By successively forming, a new roll body R can be manufactured.

On the other hand, for example, an operator conveys the shaft member SF separated for each roll body R from the bearing 51 to the delivery part 60, and attaches it to the bearing 61. The conveying operation and mounting operation of the shaft member SF may be performed automatically using a manipulator, a conveying device, or the like. After attaching the shaft member SF to the bearing 61, the unbaked film FA is sequentially taken out from the roll body R by rotating the shaft member SF, and the unbaked film FA is transferred to the chamber of the firing unit 20. It is carried in (21). In addition, when carrying the tip of the unbaked film FA into the chamber 21, it may be performed manually by an operator, or may be performed automatically using a manipulator or the like.

The unbaked film FA carried into the chamber 21 is placed on the conveying belt 23a and conveyed in the +Y direction in accordance with the rotation of the conveying belt 23a. Further, the tension may be adjusted using the tension rollers 23d and 23e. Then, while conveying the unbaked film FA, the unbaked film FA is fired using the heating unit 22.

The temperature at the time of firing varies depending on the structure of the unbaked film FA, but is preferably about 120°C to 375°C, and more preferably 150°C to 350°C. In addition, when the fine particles contain an organic material, it is necessary to set it to a temperature lower than the thermal decomposition temperature. In addition, when the coating liquid contains polyamic acid, it is preferable to complete the imidation in this firing, but the unfired film (FA) is composed of polyimide, polyamideimide or polyamide, and is micronized by the firing unit 20. This is not the case when high-temperature treatment is performed on the film formation FA.

In addition, firing conditions are, for example, when the coating liquid contains polyamic acid and/or polyimide, a method of raising the temperature from room temperature to 375°C in 3 hours, and then holding it at 375°C for 20 minutes, or from room temperature. Stepwise heating such as heating up to 375°C in steps of 50°C (holding for 20 minutes each step) and finally holding at 375°C for 20 minutes may be performed. In addition, the end of the unsaturated film FA may be fixed to a mold made of SUS or the like to prevent deformation.

By such firing, as shown in Fig. 9D, a fired film FB is formed. In the fired film FB, the fine particles A2 are contained in the imidized or high-temperature-treated resin layer A3. The film thickness of the fired film FB can be requested by measuring and averaging the thickness of a plurality of locations with, for example, a micrometer or the like. As a preferable average film thickness, when used for a separator or the like, it is preferably 3 µm to 500 µm, more preferably 5 µm to 100 µm, and still more preferably 10 µm to 30 µm.

When the fired film FB formed in the firing unit 20 is carried out from the firing unit 20, it is carried into the removal unit 30 without being wound up. In addition, when carrying the tip portion of the fired film FB into the removal unit 30, it may be performed manually by an operator, or may be performed automatically using a manipulator or the like.

The fired film FB carried into the removal unit 30 is placed on the conveying belt 35a and conveyed in the +Y direction in accordance with the rotation of the conveying belt 35a. In the removal unit 30, in accordance with the transport of the fired film FB, first, the fine particles A2 are removed by the etching part 32. When silica is used as the material of the fine particles A2, for example, the sintered film FB is immersed in an etching solution such as a low-concentration hydrogen fluoride water in the etching part 32. Thereby, the fine particles (A2) are dissolved in the etching solution and removed, and as shown in Fig. 9(e), a porous resin film (F) containing a porous portion (A4) inside the resin layer (A3) is formed. do.

After that, as the conveyance belt 35a rotates, the porous resin film F is sequentially carried into the cleaning unit 33 and the liquid removing unit 34. In the cleaning unit 33, the porous resin film F is cleaned by the cleaning liquid. Further, in the liquid removal unit 34, the porous resin film F is removed by liquid to remove the cleaning liquid. Then, the porous resin film F is carried out from the removal unit 30 and carried into the chemical etching unit 40.

The porous resin film F carried in the chemical etching unit 40 is placed on the conveying belt 42a and conveyed in the +Y direction in accordance with the rotation of the conveying belt 42a. In the chemical etching unit 40, as the porous resin film F is conveyed, a chemical etching treatment is first performed inside the porous portion A4 in the chemical etching portion 43. In the chemical etching part 43, the porous resin film F is immersed in the storage part 47 of the etching liquid EQ, and the inside of the porous part A4 is removed as shown in FIG. 9(f). In this case, while the burr of the porous portion A4 is dropped, communication properties are ensured.

After that, as the conveyance belt 42a rotates, the porous resin film F is sequentially carried into the cleaning unit 44 and the liquid removing unit 45. In the cleaning unit 44, the porous resin film F is cleaned by the cleaning liquid, and the liquid removal unit 45 removes the liquid. Further, in the liquid removal unit 45, liquid removal of the porous resin film F is performed. And, in the heating part 46, the porous resin film F after liquid removal is heated at about 100 degreeC-300 degreeC, and the cleaning liquid is removed. The porous resin film F is taken out from the chemical etching unit 40 and wound up by the shaft member SF of the winding unit 80.

As described above, the production system (SYS) according to the present embodiment fires the unbaked film FA containing the resin material (A1) and fine particles (A2) of polyamic acid, polyimide, polyamideimide or polyamide. A film forming unit 70 for forming a porous resin film F by removing fine particles A2 from the obtained fired film FB, and a chemical etching unit 40 for dissolving a part of the porous resin film F are provided. Therefore, three processes of formation of the unfired film FA, firing of the unfired film FA (formation of the fired film FB), and removal of the fine particles A2 (formation of the porous resin film F) are performed in series. It can be carried out in the flow of. Thereby, the porous resin film F can be manufactured efficiently. Moreover, since the inside of the porous part A4 is removed by the chemical etching unit 40, the porosity of the porous part A4 can be improved, and the communication property of the porous part A4 can be ensured. When such a porous resin film F is used as a separator such as a lithium ion battery, since ions move smoothly, the electrical characteristics of the battery can be improved. Accordingly, a high-quality porous resin film (F) having an excellent porosity is obtained.

In addition, the chemical etching unit 40 includes a storage unit 47 for storing the etching solution EQ, and a film transfer unit (transport unit) for immersing the imide resin film (porous resin film F) in the etchant in the storage unit. Since (42)) is provided, a chemical etching treatment can be efficiently performed on the imide-based resin film.

In addition, the imide-based resin film (porous resin film (F)) is formed in a strip shape, and the chemical etching unit 49 removes the imide-based resin film (porous resin film (F)) sent out from the film forming unit 70. Since they are introduced sequentially, they can be applied to manufacturing processes such as a roll-to-roll system, and an imide-based resin film (porous resin film (F)) can be formed efficiently.

In addition, since it is provided with a winding unit 80 for winding up the band-shaped imide resin film (porous resin film F) discharged from the chemical etching unit 40, the imide resin film subjected to the chemical etching treatment is wound up to be efficient. Can be recovered with.

In the method for producing the porous resin film (F) according to the present embodiment, fine particles are removed from a film (fired film (FB)) containing polyamic acid, polyimide, polyamideimide or polyamide, and fine particles (A2). It includes forming a porous imide resin film (porous resin film (F)) by removing and performing a chemical etching treatment to dissolve a part of the imide resin film. Three processes of firing (FA) (formation of the fired film FB) and removal of the fine particles A2 (formation of the porous resin film F) can be performed in a series of flows. Thereby, the manufacturing efficiency of the porous resin film F can be improved. Moreover, since the inside of the porous part A4 is removed by the chemical etching unit 40, the porosity of the porous part A4 can be improved, and the communication property of the porous part A4 can be ensured.

[Modified example]

In the above embodiment, a configuration in which the removal unit 30 and the chemical etching unit 40 are separated in the Y direction as separate units has been described as an example, but is not limited thereto. 10 is a diagram showing an example of a part of the manufacturing system SYS2 according to the modified example. As shown in Fig. 10, in the manufacturing system SYS2, the removal unit 230 and the chemical etching unit 240 are connected in the Y direction.

The removal unit 230 has an etching part 32, a cleaning part 33, and a liquid removal part 34. The etching part 32, the cleaning part 33, and the liquid removing part 34 are arranged side by side in the Y direction. In addition, since the configurations of the respective portions of the etching portion 32, the cleaning portion 33, and the liquid removing portion 34 are the same as those of the above-described embodiment, the description is omitted.

The chemical etching unit 240 includes a chemical etching unit 43, a cleaning unit 44, and a liquid removing unit 45. The chemical etching part 43, the cleaning part 44, and the liquid removing part 45 are arranged side by side in the Y direction. Further, since the configurations of the respective portions of the chemical etching portion 43, the cleaning portion 44, and the liquid removing portion 45 are the same as those of the above-described embodiment, a description thereof is omitted.

The removal unit 230 and the chemical etching unit 240 have a common chamber 241 and a common conveyance unit 242. The chamber 241 includes components of the removal unit 230 (etching section 32, cleaning section 33, and liquid removal section 34), and components of the chemical etching unit 240 (chemical etching section 43 ), the cleaning unit 44 and the liquid removing unit 45). The chamber 241 has an inlet port 241a for carrying in the fired film FB, and an outlet port 241b for carrying out the porous resin film F.

The transport unit 242 transports the fired film FB and the porous resin film F in the +Y direction across the removal unit 230 and the chemical etching unit 240. The conveying part 242 has a conveying belt 242a, a drive roller 242b, and driven rollers 242c to 42e. Further, in addition to the drive rollers 242b and driven rollers 242c to 242e, a support roller for supporting the conveyance belt 242a may be disposed inside the removal unit 230 or the chemical etching unit 240.

The conveyance belt 242a is formed in an endless shape and is arranged along the Y direction. The conveyance belt 242a is formed using a material having durability for each of the etching solution used in the etching portion 32 and the chemical etching solution used in the chemical etching portion 43. The conveyance belt 242a is formed in a mesh shape, for example. The conveyance belt 242a is stretched between the drive roller 242b and the driven rollers 242c to 242e so as to be substantially parallel to the XY plane in a state having tension. The porous resin film F is placed on the conveying belt 242a and conveyed.

In addition, the conveyance belt 242a may be arranged in series over the removal unit 230 and the chemical etching unit 240, but it is appropriately divided according to the etching solution and chemical etching solution used in each unit, or according to the conveyance distance of each unit. May be formed.

The driving roller 242b is disposed at an end of the chamber 241 on the +Y side. The drive roller 242b is rotatably provided around an axis parallel to the X direction. When the drive roller 242b rotates, the conveyance belt 242a rotates clockwise in FIG. 10. By rotating the conveyance belt 242a, the porous resin film F placed on the conveyance belt 242a is conveyed in the +Y direction.

The driven roller 242c is disposed at the -Y side end of the chamber 241. The driven rollers 242d and 242e are disposed on the -Z side of the driven roller 242c and the drive roller 242b, respectively. The driven rollers 242c to 242e are provided so as to be rotatable around an axis parallel to the X direction. The driven rollers 242c to 242e rotate following the rotation of the conveyance belt 42a.

In this way, the film forming unit 70 uses a liquid containing polyamic acid, polyimide, polyamideimide or polyamide, and fine particles (first coating solution (Q1), second coating solution (Q2)) as a substrate ( The coating unit 10 which is applied to the conveying substrate (S) to form an unfired film FA, and the unfired film peeled off from the substrate in or outside the coating unit is fired to form a fired film (FB) containing fine particles. A sintering unit 20 to be formed, and a removal unit 30 for forming a porous imide resin film (porous resin film F) by removing fine particles from the sintered film, and the chemical etching unit 40 is removed. Since it is connected to the unit, chemical etching can be efficiently performed on the imide resin film.

Moreover, by the said conveyance part 242, the porous resin film F is conveyed from the removal unit 230 to the chemical etching unit 240 by one conveyance belt 242a. For this reason, the transfer of the porous resin film F between the removal unit 230 and the chemical etching unit 240 is terminated. Thereby, it is possible to suppress the action of an external force on the porous resin film F as much as possible.

In addition, in the above embodiment, the configuration in which the shaft member SF is attached and detached from the bearings 51 and 81 as the winding portions 50 and 80 has been described as an example, but it is not limited to this, for example, shown in FIG. Such a winding device 90 may be used. Hereinafter, a case where the take-up device 90 is used instead of the take-up unit 50 will be described as an example.

As shown in Fig. 11, the take-up device 90 includes a frame 91, a shaft member SF, a bearing 92, a drive unit 93, and relay rollers 94a to 94e. , Has a roller support (95). The frame 91 supports the shaft member SF, the bearing 92, the drive part 93, the relay rollers 94a to 94e, and each part of the roller support part 95.

The shaft member SF winds up the unbaked film FA carried out from the application unit 10 to form a roll body R. The shaft member SF is provided so as to be detachable from the bearing 92. When the shaft member SF is mounted on the bearing 92, it is supported by the bearing 92 so as to be rotatable around an axis parallel to the X direction. By separating the shaft member SF from the bearing 92 while the roll body R is formed, the roll body R can be moved or recovered to another unit.

The relay rollers 94a to 94e feed the unbaked film FA to the shaft member SF while adjusting the tension of the unbaked film FA. The relay rollers 94a to 94e are formed in a cylindrical shape, for example, and are arranged parallel to the X direction, respectively. In the present embodiment, the unsaturated film FA is applied in the order of the relay rollers 94a, 94b, 94c, 94d, and 94e, but it is not limited thereto, and some relay rollers may not be used. Further, at least one of the relay rollers 94a to 94e may be movable by the roller support portion 95. For example, the roller support part 95 may be able to move the relay roller 94b in the Z direction or the Y direction. Further, the roller support portion 95 may be configured to rotate the relay roller 94b around the axis line AX parallel to the X axis. In this case, by feeding back the amount (distance) at which the relay roller 94b moves (rotates) to the winding speed of the bearing 92, it becomes possible to keep the tension of the unbaked film FA constant. Further, the load on the relay roller 94b may be changed by moving a movable weight (not shown) disposed on the -Y side of the relay roller 94b and disposed through the point axis. In this case, by adjusting the load applied to the relay roller 94b by the weight, it becomes possible to adjust the tension of the unbaked film FA.

The relay rollers 94a to 94e are not limited to the arrangement parallel to the X direction, and may be arranged inclined with respect to the X direction. Further, the relay rollers R21 to R25 are not limited to a cylindrical shape, and a crowned one such as a tapered type, a radial type, or a cone cave type may be used.

Further, the winding device 90 may be used in place of the winding unit 80. Further, by rotating the shaft member SF in a direction opposite to that in the case of winding a film such as the unbaked film FA, films such as the unbaked film FA can be delivered. For this reason, for example, it is possible to use the take-up device 90 instead of the delivery unit 60 described above.

[Separator]

Next, the separator 100 according to the embodiment will be described. 12 is a schematic diagram showing an example of the lithium ion battery 200, showing a state in which a part is cut away. As shown in FIG. 12, the lithium ion battery 200 has a metal case 201 and a negative electrode terminal 202 which also served as a positive electrode terminal. Inside the metal case 201, a positive electrode 201a, a negative electrode 202a, and a separator 100 are provided, and are immersed in an electrolytic solution (not shown). The separator 100 is disposed between the positive electrode 201a and the negative electrode 202a to prevent electrical contact between the positive electrode 201a and the negative electrode 202a. Lithium transition metal oxide is used as the positive electrode 201a, and lithium, carbon (graphite), or the like is used as the negative electrode 202a.

The porous resin film F described in the above embodiment is used as the separator 100 of this lithium ion battery 200. In this case, for example, the battery performance can be improved by making the surface on which the first coating film F1 is formed on the negative electrode 202a side of the lithium ion battery. In Fig. 12, the separator 100 of the prismatic lithium ion battery 200 is described as an example, but the present invention is not limited thereto. The above-described porous resin film (F) can also be used as a separator for lithium ion batteries of any type, such as a cylindrical shape or a laminate type. In addition to the lithium ion battery separator, the porous resin film F can be used as a fuel cell electrolyte membrane, a gas or liquid separation membrane, and a low dielectric constant material.

As described above, embodiments have been described, but the present invention is not limited to the above description, and various modifications can be made without departing from the gist of the present invention.

For example, in the above-described embodiments and modifications, a case where a part of the porous resin film F is removed and a case where only a chemical etching method is performed has been described as an example, but the present invention is not limited thereto. For example, a part of the porous resin film F may be removed by a method combining a chemical etching method and a physical removal method. As a physical method, for example, plasma (oxygen, argon, etc.), dry etching by corona discharge, etc., an abrasive (e.g., alumina (hardness 9), etc.) is dispersed in a liquid, and this is applied to the surface of the aromatic polyimide film. By irradiating at a speed of 30 m/s to 100 m/s, a method of treating the surface of a polyimide film, etc. can be used. These techniques are applicable both before removing the fine particles from the fired film FB in the removal unit 30 and after removing the fine particles. In addition, as a physical method applicable only after removing the fine particles, after pressing the target surface to a liquid-soaked base film (for example, a polyester film such as a PET film), without drying or after drying, It is also possible to employ a method of removing the porous resin film F from the base film. Due to the surface tension or electrostatic adhesion of the liquid, the porous resin film F is detached from the base film in a state in which only the surface layer of the porous resin film F is left on the base film.

For example, in the above-described embodiment and modified example, the case of forming an unfired film (FA) using two types of coating liquids having different content rates of fine particles was described as an example, but it is not limited to this, but one type of coating liquid It may be to form a non-film formation. In this case, either of the first nozzle 12 and the second nozzle 13 may not be used, and one of the nozzles may be omitted. When one nozzle is omitted, it is preferable to omit the first nozzle 12 and use the second nozzle 13.

In addition, in the above-described embodiment and modified example, the configuration in which the coating unit 10, the firing unit 20, the removal unit 30, and the chemical etching unit 40 are arranged one by one has been described as an example. no. For example, a plurality of at least one of the units may be provided. In this case, for example, by arranging a large number of units with a small amount (e.g., length, etc.) of the unfired film (FA), the fired film (FB) or the porous resin film (F) that can be processed per unit time, the manufacturing system (SYS) The overall manufacturing efficiency can be improved.

In addition, in the above-described embodiments and modifications, each unit of the coating unit 10, the firing unit 20, the removal unit 30, and the chemical etching unit 40 is an unfired film (FA) and a fired film (FB). Alternatively, although the case where each film of the porous resin film F is conveyed along the Y direction has been described as an example, it is not limited thereto. For example, several units may convey the film in the X-direction, Y-direction, Z-direction, or these synthesis directions, and may change the conveyance direction suitably within one unit.

Further, in addition to the configuration of the above embodiment, a post-treatment unit for performing post-treatment on the porous resin film F partially removed by the chemical etching unit 40 may be provided. Examples of the post-treatment unit include an antistatic unit that performs an antistatic treatment on the porous resin film F. An antistatic device such as an ionizer is mounted on the antistatic unit.

In addition, in the above-described embodiment and modified example, the case where three steps of application in the coating unit 10, firing in the firing unit 20, and removal in the removal unit 30 are performed is described as an example. It is not limited to. For example, when polyimide, polyamideimide, or polyamide is used as the material of the coating film, it is not necessary to perform firing. For this reason, when not firing, for example, by providing a take-up device and a delivery device between the firing unit 20 and the removal unit 30, the unbaked film FA formed in the coating unit 10, It becomes possible to carry in the removal unit 30 without the case of intervening the firing unit 20. In addition, when not firing, the production system for producing a porous imide-based resin film is a coating in which a liquid containing polyamic acid, polyimide, polyamideimide, or polyamide and fine particles is applied to the substrate to form a green film. A manufacturing system comprising a unit and a removal unit for removing the fine particles from the unbaked film peeled from the substrate in or outside the coating unit. In addition, when not firing, after carrying out the porous resin film F from the removal unit 30 for removing fine particles, the above-described post-baking treatment process may be performed. Moreover, you may pass through the chemical etching unit 40 before the post-baking process process. In this case, the post-baking treatment process may be performed by the heating unit 46.

In addition, in the above-described embodiments and modifications, a configuration for forming the porous resin film F by a so-called roll-to-roll system has been described as an example, but is not limited thereto. For example, after the processing in the chemical etching unit 40 is finished, when the porous resin film F is taken out from the chemical etching unit 40, a predetermined length without being wound by the winding unit 80 It cuts with and may collect what was cut|disconnected.

SYS, SYS2... Manufacturing system F… Porous resin film (imide resin film) FA... Small film formation FB... Firing film S… Equipment to be conveyed (substrate) Q1... 1st coating liquid (liquid) Q2... 2nd coating liquid (liquid) EQ... Etching solution A1... Resin material A2... Particulate A4... Porous part 10... Application unit 20... Firing units 30, 230... Removal unit 40, 240... Chemical etching unit 42... Transfer section 43... Chemical etching part 47... Storage 70... Film forming unit 100... Separator 200... Lithium ion battery

Claims (6)

As a manufacturing system for manufacturing a porous imide-based resin film,
A film forming unit for forming the porous imide-based resin film by removing the fine particles from a film containing at least one selected from the group consisting of polyamic acid, polyimide, polyamideimide and polyamide, and fine particles,
At least one nozzle of a film conveying unit for mounting and conveying the imide-based resin film, an upper nozzle for discharging an etchant from above the imide-based resin film, and a lower nozzle for discharging an etchant from a lower side of the imide-based resin film, and the at least An imide-based resin film production system comprising a storage unit for storing an etchant discharged from one nozzle, and a chemical etching unit for dissolving a part of the imide-based resin film by the etchant in the storage unit. The method according to claim 1,
The film conveying part of the chemical etching unit is an imide-based resin film for dissolving a part of the imide-based resin film by an etchant in the storage part while the imide-based resin film is pushed up by an etchant discharged from the lower nozzle. Manufacturing system. The method according to claim 1,
The imide-based resin film is formed in a strip shape,
The chemical etching unit sequentially introduces the imide resin film sent out from the film forming unit. The method according to claim 1,
An imide-based resin film production system comprising a winding portion for winding up the band-shaped imide-based resin film discharged from the chemical etching unit. The method according to any one of claims 1 to 4,
The film forming unit includes a coating unit for forming a green film by applying a liquid containing at least one selected from the group consisting of polyamic acid, polyimide, polyamideimide, and polyamide, and fine particles to a substrate, and the application A firing unit for firing the unfired film peeled off from the substrate in the unit or outside the coating unit to form a fired film containing the microparticles, and removing the microparticles from the fired film to form the porous imide resin film Includes a unit,
The chemical etching unit is an imide resin film production system connected to the removal unit. As a method for producing a porous imide-based resin film,
Forming the porous imide-based resin film by removing the fine particles from a film containing at least one selected from the group consisting of polyamic acid, polyimide, polyamideimide, and polyamide, and fine particles,
A method for producing an imide-based resin film comprising carrying out a chemical etching treatment of dissolving a part of the imide-based resin film with an etching solution discharged from at least one of the upper and lower sides of the imide-based resin film while transporting the imide-based resin film. .

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