JP2016055541A - Firing device, firing method, production system and production method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent damage of an unfired film.SOLUTION: A firing device includes a belt-like conveyance belt 23a capable of moving in the loaded state of an unfired film FA formed of liquid containing a prescribed resin material and fine particles, and a heating part 22 for firing the unfired film FA, while conveying it by the conveyance belt 23a.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a baking apparatus, a baking method, a manufacturing system, and a manufacturing 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 soaked in an electrolyte, and the separator prevents direct electrical contact between the positive electrode and the negative electrode. Yes. A 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 pass from the positive electrode through the separator to the negative electrode, and during discharging, lithium ions pass from the negative electrode through the separator to the positive electrode. In recent years, it has been known to use a separator made of a porous polyimide film having high heat resistance and high safety as such a separator (see, for example, Patent Document 1). The porous polyimide film is formed by, for example, coating and forming a polyamide acid or polyimide unfired film containing fine particles, firing the unfired film to form a fired film, and removing the fine particles from the fired film. Is formed.

JP 2011-111470 A

  However, when firing an unfired film, there is a period during which the composition of the unfired film changes due to heating and becomes brittle. Therefore, the structure which can be conveyed so that an unbaked film | membrane may not be damaged is calculated | required.

  In view of the circumstances as described above, it is an object of the present invention to provide a baking apparatus, a baking method, a manufacturing system, and a manufacturing method capable of preventing the unfired film from being damaged.

  The firing apparatus according to the first aspect of the present invention includes a belt-shaped transport member that can move by placing an unfired film formed from a liquid containing polyamic acid, polyimide, polyamideimide, or polyamide, and fine particles, and a transport And a firing section that fires the unfired film while being conveyed by the member.

  The firing method according to the second aspect of the present invention includes transporting an unfired film formed from a liquid containing polyamic acid, polyimide, polyamideimide, or polyamide, and fine particles on a belt-like transport member. And firing while the unsintered film is transported by the transport member.

  The manufacturing system which concerns on the 3rd aspect of this invention is a manufacturing system which manufactures a porous imide-type resin film, Comprising: The baking apparatus which concerns on the 1st aspect of this invention is included.

  The manufacturing method according to the fourth aspect of the present invention is a method for manufacturing a porous imide-based resin film, and includes the firing method according to the second aspect of the present invention.

  According to the aspect of the present invention, it is possible to prevent the unfired film from being damaged.

It is a figure which shows an example of the manufacturing system which concerns on 1st Embodiment. It is a figure which shows an example of the manufacturing system which concerns on this embodiment. It is a figure which shows an example of the nozzle provided in the coating unit which concerns on this embodiment. It is a perspective view which shows an example of the winding part which concerns on this embodiment. It is a perspective view which shows an example of the baking unit which concerns on this embodiment. It is a figure which shows an example of the baking unit which concerns on this embodiment. It is a perspective view which shows an example of the winding part which concerns on this embodiment. It is a figure which shows an example of the manufacture process of the imide type resin film which concerns on this embodiment. It is a figure which shows an example of the baking unit which concerns on a modification. It is a figure which shows an example of the baking unit which concerns on a modification. It is a figure which shows an example of the manufacturing system which concerns on a modification. It is a figure which shows an example of the winding apparatus which concerns on a modification. It is a figure which shows an example of the separator which concerns on embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Hereinafter, directions in the figure will be described using an XYZ coordinate system. In this XYZ coordinate system, a plane parallel to the horizontal plane is defined as an XY plane. One direction parallel to the XY plane is expressed as an X direction, and a direction orthogonal to the X direction is expressed as a Y direction. A direction perpendicular to the XY plane is expressed as a Z direction. In each of the X direction, the Y direction, and the Z direction, the direction of the arrow in the figure is the + direction, and the direction opposite to the arrow direction is the − direction.

  1 and 2 are diagrams illustrating an example of the manufacturing system SYS according to the present embodiment. The manufacturing system SYS shown in FIGS. 1 and 2 manufactures a porous resin film F (porous imide resin film). The manufacturing system SYS applies a predetermined coating solution to form the unfired film FA, the firing unit 20 to fire the unfired film FA to form the fired film FB, and fine particles from the fired film FB. A removal unit (etching apparatus) 30 that removes to form a porous resin film F and a control apparatus (not shown) that controls the above units in an integrated manner are provided.

  The manufacturing system SYS is configured, for example, in two upper and lower layers, the coating unit 10 is disposed on the second floor portion, and the baking unit 20 and the removal unit 30 are disposed on the first floor portion. The firing unit 20 and the removal unit 30 arranged on the same floor are arranged side by side in the Y direction, for example, but are not limited to this, for example, arranged in the X direction or the combined direction of the X direction and the Y direction. It may be arranged.

  The hierarchical structure of the manufacturing system SYS and the arrangement of each unit on each floor are not limited to the above. For example, the coating unit 10 and the baking unit 20 are arranged on the second floor part, and the removal unit 30 is on the first floor part. It may be arranged. All units may be arranged on the same floor. In this case, each unit may be arranged in a row or in a plurality of rows. Further, all the units may be arranged on different levels.

  In the manufacturing system SYS, the unfired film FA is formed in a band shape. On the + Y side of the coating unit 10 (front in the transport direction of the unfired film FA), a winding unit 50 that winds the belt-like unfired film FA into a roll is provided. On the -Y side of the firing unit 20 (rear in the transport direction of the unfired film FA), a delivery unit 60 that feeds the roll-like unfired film FA toward the firing unit 20 is provided. On the + Y side of the removal unit 30 (front in the transport direction of the fired film FB), a winding unit 80 that winds the porous resin film F into a roll is provided.

  In this way, in the section (first floor portion) from the delivery unit 60 to the winding unit 80 through the firing unit 20 and the removal unit 30, processing by a so-called roll-to-roll method is performed. Accordingly, in this section, the unfired film FA, the fired film FB, and the porous resin film F are conveyed in a continuous state.

[Coating solution]
Here, before explaining each unit, the coating liquid used as the raw material of the porous resin film F is demonstrated. The coating liquid contains a predetermined resin material, fine particles, and a solvent. Examples of the predetermined resin material include polyamic acid, polyimide, polyamideimide, and polyamide. As the solvent, an organic solvent capable of dissolving these resin materials is used.

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

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

  In the above case, when the volume of the fine particles is 65 or more when the entire volume of the first coating liquid is 100, the particles are uniformly dispersed, and when the volume of the fine particles is within 81, the particles are aggregated. Disperse without doing. For this reason, holes can be formed uniformly in the porous resin film F. Moreover, if the volume ratio of the fine particles is within this range, the releasability when the unfired film FA is formed can be ensured.

  If the volume of the fine particles is 50 or more when the total volume of the second coating liquid is 100, the fine particles are uniformly dispersed, and if the volume is within 80 of the fine particles, the fine particles are not aggregated, Moreover, since no cracks or the like are generated on the surface, the porous resin film F having good electric characteristics can be formed stably.

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

  The viscosity of the coating solution is preferably finally 300 to 2500 cP, more preferably 400 to 1500 cP, and even more preferably 600 to 1200 cP. If the viscosity of the coating solution is within this range, it is possible to form a film uniformly.

  In the coating solution, when the fine particles and the polyamic acid or polyimide are dried to form an unfired film FA, the fine particle / polyimide ratio is 2 to 6 (mass ratio) when the material of the fine particles is an inorganic material described later. The fine particles and polyamic acid or polyimide may be mixed so as to be. More preferably, it is 3-5 (mass ratio). When the material of the fine particles is an organic material described later, the fine particles and the polyamic acid or the polyimide may be mixed so that the fine particle / polyimide ratio is 1 to 3.5 (mass ratio). It is still more preferable to set it as 1.2-3 (mass ratio). Moreover, it is good to mix a microparticle and a polyamic acid or a polyimide so that the volume ratio of microparticles / polyimide may be 1.5 to 4.5 when the unfired film FA is formed. More preferably, it is 1.8-3 (volume ratio). If the fine particle / polyimide mass ratio or volume ratio is equal to or higher than the lower limit when the unfired film FA is used, pores having an appropriate density as a separator can be obtained. It is possible to form a film stably without causing problems such as cracks inside. When the resin material is polyamide-imide or polyamide instead of polyamic acid or polyimide, the mass ratio is the same as above.

Hereinafter, each resin material will be specifically described.
<Polyamide acid>
As the polyamic acid used in the present embodiment, one obtained by polymerizing an arbitrary tetracarboxylic dianhydride and diamine can be used without any particular limitation. Although the usage-amount of tetracarboxylic dianhydride and diamine is not specifically limited, It is preferable to use 0.50-1.50 mol of diamine with respect to 1 mol of tetracarboxylic dianhydrides, and 0.60-1. It is more preferable to use 30 mol, and it is particularly preferable to use 0.70 to 1.20 mol.

  The tetracarboxylic dianhydride can be appropriately selected from tetracarboxylic dianhydrides conventionally used as raw materials for synthesizing polyamic acid. The tetracarboxylic dianhydride may be an aromatic tetracarboxylic dianhydride or an aliphatic tetracarboxylic dianhydride. From the viewpoint of the heat resistance of the resulting polyimide resin, the aromatic tetracarboxylic dianhydride may be used. Preference is given to using carboxylic dianhydrides. Tetracarboxylic dianhydride may be used in combination of two or more.

  Preferable specific examples of the aromatic tetracarboxylic dianhydride include pyromellitic dianhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane dianhydride, bis (2,3-dicarboxy). Phenyl) methane dianhydride, 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-dicarboxy Enyl) -1,1,1,3,3,3-hexafluoropropane dianhydride, 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride, bis (3,4-dicarboxyphenyl) Ether dianhydride, bis (2,3-dicarboxyphenyl) ether dianhydride, 2,2 ′, 3,3′-benzophenonetetracarboxylic dianhydride, 4,4- (p-phenylenedioxy) diphthal Acid dianhydride, 4,4- (m-phenylenedioxy) diphthalic dianhydride, 1,2,5,6-naphthalene tetracarboxylic dianhydride, 1,4,5,8-naphthalene tetracarboxylic acid di Anhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 1,2,3,4-benzenetetracarboxylic dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride , 2, 3 6,7-anthracenetetracarboxylic dianhydride, 1,2,7,8-phenanthrenetetracarboxylic dianhydride, 9,9-bisphthalic anhydride fluorene, 3,3 ′, 4,4′-diphenylsulfone Tetracarboxylic dianhydride etc. are mentioned. Examples of the aliphatic tetracarboxylic dianhydride include 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. 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 synthesizing polyamic acid. The diamine may be an aromatic diamine or an aliphatic diamine, but an aromatic diamine is preferred from the viewpoint of the heat resistance of the resulting polyimide resin. These diamines may be used in combination of two or more.

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

  Phenylenediamine is m-phenylenediamine, p-phenylenediamine, etc., and phenylenediamine derivatives include diamines to which alkyl groups such as methyl group and ethyl group are bonded, such as 2,4-diaminotoluene, 2,4-triphenylene. Diamines and the like.

  The diaminobiphenyl compound is a compound in which two aminophenyl groups are bonded to each other. For example, 4,4'-diaminobiphenyl, 4,4'-diamino-2,2'-bis (trifluoromethyl) biphenyl, and the like.

  The diaminodiphenyl compound is a compound in which two aminophenyl groups are bonded to each other via other groups. The bond is an ether bond, a sulfonyl bond, a thioether bond, a bond by alkylene or a derivative group thereof, an imino bond, an azo bond, a phosphine oxide bond, an amide bond, a ureylene bond, or the like. The alkylene bond has about 1 to 6 carbon atoms, and the derivative group has one or more hydrogen atoms in the alkylene group substituted with halogen atoms or the like.

  Examples of diaminodiphenyl compounds include 3,3′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, 4,4′-diaminodiphenyl ether, 3,3′-diaminodiphenyl sulfone, 3,4′-diaminodiphenyl sulfone, 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl sulfide, 3,3'-diaminodiphenyl ketone 3,4′-diaminodiphenyl ketone, 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-aminophen ) Phenyl] hexafluoropropane, 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 both bonded via other groups, and the other groups are 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, 1,4-bis (p-aminophenoxy) benzene, and the like. be able to.

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

  Examples of aminophenylaminoindane include 5 or 6-amino-1- (p-aminophenyl) -1,3,3-trimethylindane.

  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, and the like.

  Examples of the cardo type fluoreneamine derivative include 9,9-bisaniline fluorene.

  The aliphatic diamine has, for example, about 2 to 15 carbon atoms, and specific examples include pentamethylenediamine, hexamethylenediamine, and heptamethylenediamine.

  A compound in which the hydrogen atom of these diamines is 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 may be used.

  There is no restriction | limiting in particular in the means to manufacture the polyamic acid used by this embodiment, For example, well-known methods, such as the method of making an acid and a diamine component react in an organic solvent, can be used.

  Reaction of tetracarboxylic dianhydride and diamine is normally performed in an organic solvent. The organic solvent used for the reaction of the tetracarboxylic dianhydride and the diamine is particularly capable of dissolving the tetracarboxylic dianhydride and the diamine and not reacting with the tetracarboxylic dianhydride and the diamine. It is not limited. An organic solvent can be used individually or in mixture of 2 or more types.

  Examples of the organic solvent used for 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, N-diethylformamide, N-methylcaprolactam, N, N, N ′, N′-tetramethylurea; β-propiolactone, γ-butyrolactone, γ-valerolactone Lactone polar solvents such as δ-valerolactone, γ-caprolactone and ε-caprolactone; dimethyl sulfoxide; acetonitrile; fatty acid esters such as ethyl lactate and butyl lactate; diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dioxane, Tetrahydrofuran, methyl cellosolve acetate Over DOO, ethers such as ethyl cellosolve acetate; include phenolic solvents cresols, and the like. These organic solvents can be used alone or in admixture of two or more. Although there is no restriction | limiting in particular in the usage-amount of an organic solvent, It is desirable for content of the polyamic acid to produce | generate to be 5-50 mass%.

  Among these organic solvents, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-diethylacetamide, N, N-dimethylformamide, N, N- Nitrogen-containing polar solvents such as diethylformamide, N-methylcaprolactam, N, N, N ′, N′-tetramethylurea are preferred.

  The polymerization temperature is generally -10 to 120 ° C, preferably 5 to 30 ° C. The polymerization time varies depending on the raw material composition to be used, but is usually 3 to 24 Hr (hour). Moreover, the intrinsic viscosity of the organic solvent solution of polyamic acid obtained under such conditions is preferably in the range of 1000 to 100,000 cP (centipoise), and more preferably in the range of 5,000 to 70,000 cP.

<Polyimide>
The polyimide used in the present embodiment is not limited to its structure and molecular weight, and any known polyimide can be used as long as it is a soluble polyimide that can be dissolved in the organic solvent used in the coating solution. About a polyimide, you may have a functional group which accelerates | stimulates a crosslinking reaction etc. at the time of baking, or a functional group which can be condensed, such as a carboxy group.

  Use of a monomer to introduce a flexible bending structure into the main chain in order to obtain a polyimide soluble in an organic solvent, such as ethylenediamine, hexamethylenediamine, 1,4-diaminocyclohexane, 1,3-diaminocyclohexane, Aliphatic diamines such as 4,4′-diaminodicyclohexylmethane; 2-methyl-1,4-phenylenediamine, o-tolidine, m-tolidine, 3,3′-dimethoxybenzidine, 4,4′-diaminobenzanilide, etc. Aromatic diamines; polyoxyalkylene diamines such as polyoxyethylene diamine, polyoxypropylene diamine, polyoxybutylene diamine; polysiloxane diamines; 2,3,3 ′, 4′-oxydiphthalic anhydride, 3,4,3 ′, 4′-oxydiphthalic anhydride, 2,2-bis (4- Rokishifeniru) propane dibenzoate-3,3 ', use of such 4,4'-tetracarboxylic dianhydride is valid. In addition, 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-1,4 -It is also effective to use a fluorinated diamine such as phenylenediamine. Furthermore, in addition to the monomer for improving the solubility of the polyimide, the same monomers as those described in the column for the polyamic acid can be used in combination as long as the solubility is not inhibited.

  There is no restriction | limiting in particular in the means which manufactures the polyimide which can be melt | dissolved in the organic solvent used by this invention, For example, well-known methods, such as the method of making a polyamic acid chemically imidate or heat imidize, and making it melt | dissolve in an organic solvent, are used. be able to. Examples of such polyimide include aliphatic polyimide (total aliphatic polyimide), aromatic polyimide and the like, and aromatic polyimide is preferable. The aromatic polyimide is obtained by thermally or chemically obtaining a polyamic acid having a repeating unit represented by the formula (1) by a ring-closing reaction or by dissolving a polyimide having a repeating unit represented by the formula (2) in a solvent. Good. In the formula, Ar represents an aryl group.

<Polyamideimide>
As the polyamideimide used in the present embodiment, any known polyamideimide can be used as long as it is a soluble polyamideimide that can be dissolved in an organic solvent used in the coating solution, without being limited to its structure and molecular weight. The polyamideimide may have a functional group capable of condensing such as a carboxy group in the side chain or a functional group that promotes a crosslinking reaction or the like during firing.

  The polyamideimide used in the present embodiment is obtained by reacting any trimellitic anhydride and diisocyanate, or a precursor polymer obtained by reacting any reactive derivative of trimellitic anhydride with diamine. What is obtained by forming can be used without particular limitation.

  Examples of the arbitrary trimellitic anhydride and acid or a reactive derivative thereof include trimellitic anhydride halides such as trimellitic anhydride and trimellitic anhydride chloride, trimellitic anhydride ester, and the like.

  Examples of the diisocyanate include metaphenylene diisocyanate, p-phenylene diisocyanate, 4,4′-oxybis (phenylisocyanate), 4,4′-diisocyanatediphenylmethane, bis [4- (4-isocyanatephenoxy) phenyl] sulfone, 2, And 2'-bis [4- (4-isocyanatophenoxy) phenyl] propane.

  Examples of the diamine include those similar to those exemplified in the description of the polyamic acid.

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

  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 Etc.

  Examples of the diamine include those similar to those exemplified in the description of the polyamic acid.

<Fine particles>
Subsequently, the fine particles will be described. For example, fine particles having a high sphericity and a small particle size distribution index are used. Such fine particles are excellent in dispersibility in a liquid and do not aggregate with each other. The particle size (average diameter) of the fine particles can be set to about 100 to 2000 nm, for example. By using the fine particles as described above, the pore diameter of the porous resin film F obtained by removing the fine particles in a later step can be made uniform. For this reason, the electric field applied to the separator formed by the porous resin film F can be made uniform.

The fine particle material is not particularly limited as long as it is a material that is insoluble in the solvent contained in the coating solution and can be removed from the porous resin film F in a later step. can do. For example, the inorganic materials, silica (silicon dioxide), metal oxides such as titanium oxide, alumina _(Al 2 _{O 3)} can be mentioned. Examples of organic materials include high molecular weight olefins (polypropylene, polyethylene, etc.), polystyrene, epoxy resin, cellulose, polyvinyl alcohol, polyvinyl butyral, polyester, polymethyl methacrylate, polyether, and other organic polymer fine particles. Examples of the fine particles include colloidal silica such as (monodispersed) spherical silica particles, calcium carbonate, and the like. In this case, the pore diameter of the porous resin film F can be made more uniform.

  Further, the fine particles contained in the first coating solution and the fine particles contained in the second coating solution may have the same specifications such as sphericity, particle size, material, etc., or may be different from each other. The fine particles contained in the first coating solution preferably have a smaller or the same particle size distribution index as the fine particles contained in the second coating solution. Alternatively, it is preferable that the fine particles contained in the first coating solution have a smaller or the same sphericity as the fine particles contained in the second coating solution. The fine particles contained in the first coating solution preferably have a smaller particle diameter (average diameter) than the fine particles contained in the second coating solution. Particularly, the fine particles contained in the first coating solution have a particle size of 100 to 1000 nm. (More preferably 100 to 600 nm), and the fine particles contained in the second coating solution are preferably 500 to 2000 nm (more preferably 700 to 2000 nm). By using a particle size of the fine particles contained in the first coating film that is smaller than the particle size of the fine particles contained in the second coating solution, the opening ratio 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 as compared with the case where the entire porous resin film F is made the particle size of the fine particles contained in the first coating liquid.

  The coating solution contains various additives such as a mold release agent, a dispersant, a condensing agent, an imidizing agent, and a surfactant as required in addition to a predetermined resin material, fine particles, and a solvent. May be.

[Coating unit]
The coating unit 10 includes a transport unit 11, a first nozzle 12, a second nozzle 13, a drying unit 14, and a peeling unit 15.
The transport unit 11 includes a transport base material (base material) S, a base material feed 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 conveyance base material S is sent out from the base material feed roller 11a, is stretched around the support rollers 11b to 11d so as to have a tension, and is taken up by the base material take-up roller 11e. Examples of the material of the transport substrate S include polyethylene terephthalate (PET), but are not limited thereto, and may be a metal material such as stainless steel.

  Each of the rollers 11a to 11f is formed in a cylindrical shape, for example, and is arranged in parallel to the X direction. Each of the rollers 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 roller 11a-11f may be arrange | positioned in parallel with a Z direction, and may be arrange | positioned so that the height position of a Z direction may become the same. In this case, the conveyance base material S moves along the horizontal plane while standing on the horizontal plane (XY plane).

  The base material feed roller 11a is arranged in a state where the transport base material S is wound. The support roller 11b is disposed on the + Z side of the base material feed roller 11a, and is disposed on the −Y side of the base material feed roller 11a. The support roller 11c is disposed on the + Z side of the support roller 11b, and is disposed on the + Y side of the support roller 11b. Due to the arrangement of these three rollers (base material feed roller 11a, support rollers 11b, 11c), the transport base material S is supported on the surface including the −Y side end portion of the support roller 11b.

  The support roller 11d is disposed on the + Y side of the support roller 11c, and is disposed on the −Z side of the support roller 11c. In this case, the conveyance base material S is supported on the surface including the + Z side end portion of the support roller 11c by the arrangement of the three rollers of the support rollers 11b to 11d.

  The support roller 11d may be disposed at a height position substantially equal to the height position (position in the Z direction) of the support roller 11c. In this case, the transport substrate S is fed in the + Y direction from the support roller 11c toward the support roller 11d in a state substantially parallel to the XY plane.

  The substrate winding roller 11e is arranged on the −Z side of the support roller 11d. The transport substrate S is sent in the −Z direction from the support roller 11d toward the substrate take-up roller 11e. 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 unfired film FA formed by the drying unit 14 in the + Y direction. This unfired film FA is carried out of the coating unit 10 by the carry-out roller 11f.

  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 correcting the deflection of the rollers 11a to 11f, and the transport base material S or an unfired film FA described later can contact the rollers 11a to 11f evenly. Further, a radial crown may be formed on the rollers 11a to 11f. In this case, it is effective for preventing meandering of the transport substrate S or the unfired film FA. Further, a concave 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, it is possible to transport the transport substrate S or the unfired film FA while applying tension in the X direction, which is effective in preventing wrinkles. Similarly to the above, the following rollers may have a taper type, radial type, concave type crown or the like.

  FIG. 3A is a perspective view showing an example of the first nozzle 12. As shown in FIGS. 2 and 3A, the first nozzle 12 forms a coating film (hereinafter, referred to as a first coating film F1) of the first coating liquid EQ1 on the transport substrate S. The first nozzle 12 has a discharge port 12a that discharges the first coating liquid EQ1. The discharge port 12a is formed, for example, such that the longitudinal direction is substantially the same as the dimension of the transport substrate S in the X direction.

  The first nozzle 12 is disposed at the discharge position P1. The discharge position P1 is a position on the −Y direction with respect to the support roller 11b. The first nozzle 12 is disposed to be inclined such that the discharge port 12a faces the + Y direction. Accordingly, the discharge port 12a is directed to the portion of the transport base S that is supported by the −Y side end of the support roller 11b. The first nozzle 12 discharges the first coating liquid EQ1 along the horizontal direction from the discharge port 12a to the transport substrate S.

  FIG. 3B is a perspective view showing an example of the second nozzle 13. As shown in FIGS. 2 and 3B, the second nozzle 13 overlaps the first coating film F1 on the transport substrate S, and the coating film of the second coating liquid EQ2 (hereinafter referred to as the second coating film F2). Form). The second nozzle 13 has a discharge port 13a that discharges the second coating liquid EQ2. The discharge port 13a is formed, for example, so that the longitudinal direction is substantially the same as the dimension of the transport base S in the X direction.

  The second nozzle 13 is disposed at the discharge position P2. The discharge position P2 is a position on the + Z direction with respect to the support roller 11c. The second nozzle 13 is disposed such that the discharge port 13a faces the −Z direction. Accordingly, the discharge port 13a is directed to the portion of the transport base S that is supported by the + Z side end of the support roller 11c. The 2nd nozzle 13 discharges the 2nd coating liquid EQ2 with respect to this conveyance base material S along the gravity direction from the discharge outlet 13a.

  Note that the first nozzle 12 and the second nozzle 13 may be movable in at least one of the X direction, the Y direction, and the Z direction. 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. The first nozzle 12 and the second nozzle 13 are arranged at a standby position (not shown) when the coating liquid is not discharged, and move from the standby position to the discharge positions P1 and P2 when discharging the coating liquid, respectively. It may be. Moreover, the part which performs the preliminary discharge operation | movement of the 1st nozzle 12 and the 2nd nozzle 13 may be provided.

  The first nozzle 12 and the second nozzle 13 are each connected to a coating liquid supply source (not shown) via a connection pipe (not shown). The first nozzle 12 and the second nozzle 13 are provided with a holding unit (not shown) for holding a predetermined amount of coating liquid, for example. In this case, the first nozzle 12 and the second nozzle 13 may include a temperature adjustment unit that adjusts the temperature of the liquid material held in the holding unit.

  The coating amount of each coating liquid coated from the first nozzle 12 or the second nozzle 13 and the film thickness of the first coating film F1 or the second coating film F2 are determined by the nozzles, the connection pipes (not shown), or Adjustment is possible by the pressure of a pump (not shown) connected to a coating liquid supply source (not shown), the conveyance speed, the position of each nozzle or the distance between the conveyance substrate S and the nozzle, and the like. 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.

  When two types of coating liquids (first coating liquid EQ1 and second coating liquid EQ2) are used as in this embodiment, the film thickness of the first coating film F1 by the first coating liquid EQ1 is, for example, 0. It is preferable to adjust in the range of 5 μm to 10 μm and adjust the film thickness of the second coating film F2 by the second coating liquid EQ2 in the range of 1 μm to 50 μm, for example.

  In addition, you may arrange | position the drying part (not shown) for drying the 1st coating film F1 between the 1st nozzle 12 and the 2nd nozzle 13. FIG. This drying section preferably includes a heat drying section. As the heating and drying unit, it is preferable to use a hot air blowing unit or an infrared heater. 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, for example, it is possible to prevent the fine particles used in the second coating liquid from being mixed with the fine particles of the first coating film F1. Can do.

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

  The drying unit 14 includes a chamber 14a and a heating unit 14b. The chamber 14a accommodates the transport substrate S and the heating unit 14b. The heating unit 14b heats the first coating film F1 and the second coating film F2 formed on the transport substrate S. For example, an infrared heater is used as the heating unit 14b. 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 where the unfired film FA is peeled from the transport substrate S. In the present embodiment, the unsintered film FA is peeled off manually by the operator, but the present invention is not limited to this, and it may be automatically performed using a manipulator or the like. The unsintered film FA peeled off from the transport substrate S is carried out of the coating unit 10 by the carry-out roller 11 f and sent to the winding unit 50. Further, the transport substrate S from which the unfired film FA has been peeled is wound up by the substrate winding roller 11e.

[Winding part (1)]
FIG. 4 is a perspective view schematically showing a configuration on the + Y side of the coating unit 10.
As shown in FIG. 4, on the + Y side of the coating unit 10, a carry-out port 10b for carrying out the unfired film FA is provided. The unsintered film FA carried out from the carry-out port 10 b is taken up by the take-up unit 50.

  The winding unit 50 is configured such that the shaft member SF is mounted on the bearing 51. The shaft member SF forms the roll body R by winding up the unfired film FA carried out from the carry-out port 10b. The shaft member SF is provided so as to be detachable from the bearing 51. When the shaft member SF is attached to the bearing 51, the shaft member SF 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) that rotates the shaft member SF attached to the bearing 51.

  In the winding unit 50, the unsintered film FA is wound so that the surface of the unsintered film FA on the first coating film F1 side is disposed outside. For example, the unfired film FA is wound up by rotating the shaft member SF counterclockwise in FIG. 2 by a drive mechanism. By removing the shaft member SF from the bearing 51 in a state where the roll body R is formed, the roll body R can be moved to another unit.

  In FIGS. 2 and 4, the winding unit 50 is disposed independently from the coating unit 10, but is not limited thereto. For example, the winding unit 50 may be disposed inside the coating unit 10. In this case, the roll body R may be formed by winding the unfired film FA from the carry-out roller 11f (or from the support roller 11d) without arranging the carry-out port 10b in the coating unit 10.

[Sending part]
FIG. 5 is a perspective view schematically showing a configuration on the −Y side of the firing unit 20. However, in FIG. 5, a removing unit 26 described later is omitted.
As shown in FIG. 5, on the −Y side of the baking unit 20, a carry-in port 20 a for carrying the unfired film FA is provided. The sending-out unit 60 sends out the unfired film FA to the carry-in port 20a.

  The delivery portion 60 is configured such that the shaft member SF can be attached to the bearing 61. The shaft member SF can be used in common with that mounted on the bearing 51 of the winding unit 50. Therefore, the shaft member SF removed from the winding unit 50 can be mounted on the bearing 61 of the delivery unit 60. Thereby, the roll body R formed by the winding unit 50 can be arranged in the delivery unit 60. In addition, about the bearing 61 and the bearing 51 of the winding-up part 50, although it can set so that the height from a floor surface may become equal, respectively, you may set to a different height position.

  When the shaft member SF is attached to the bearing 61, the shaft member SF 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 attached to the bearing 61. By rotating the shaft member SF clockwise in FIG. 2 by the driving mechanism, the unfired film FA constituting the roll body R is sent out toward the carry-in entrance 20a. In the winding unit 50, the unfired film FA is wound so that the surface of the unfired film FA on the first coating film F1 side is disposed on the outside. Is pulled out, the first coating film F1 side is arranged upward.

[Baking unit]
FIG. 6 is a diagram illustrating an example of the firing unit 20. 6A is a diagram showing a cross-sectional configuration along the YZ plane, and FIG. 6B is a diagram showing a configuration when the inside of the chamber 21 is viewed in the −Z direction.

  As shown in FIG. 6, the firing unit 20 is a unit that performs high-temperature processing on the unfired 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 includes a chamber 21, a heating unit (baking unit) 22, a transport unit 23, a belt cooling unit (cooling unit) 24, an exhaust unit 25, and a removing unit 26.

  The chamber 21 is disposed on the base frame BF and has a ceiling portion 21a and a bottom portion 21b. In the chamber 21, a carry-in port 20a for carrying in the unfired film FA and a carry-out port 20b for carrying out the fired film FB are formed. The chamber 21 accommodates a heating unit 22, a transport unit 23, and a belt cooling unit 24. The chamber 21 is provided with an atmosphere adjusting unit 21c. The atmosphere adjusting unit 21c adjusts the atmosphere around the unfired film FA. The atmosphere adjusting unit 21c can supply an inert gas such as nitrogen gas into the chamber 21, for example, and can adjust the periphery of the unfired film FA to an atmosphere of an inert gas.

  The heating unit 22 heats the unsintered film FA carried into the chamber 21. The heating unit 22 includes a plurality of heaters 22a arranged side by side in the Y direction. The plurality of heaters 22a are arranged on the + Z side of the unfired film FA. Therefore, the heating unit 22 is configured to heat the unsintered film FA from the surface (+ Z side surface) side of the unsintered film FA. For example, an infrared heater is used as the heater 22a.

  The heating unit 22 is disposed from the −Y side end inside the chamber 21 to the + Y side end. The heating unit 22 can heat the unsintered film FA almost entirely in the Y direction. The heating unit 22 can heat the unfired film FA to 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 unfired film FA, the constituent components of the unfired film FA, and the like. Moreover, the heating part 22 can form a temperature gradient in the Y direction by adjusting the output for each heater 22a, for example.

  The conveyance unit 23 includes a conveyance belt 23a, a driving roller 23b, a driven roller 23c, and tension rollers 23d and 23e. The conveyor belt 23a is formed in an annular shape and is disposed along the Y direction. The conveyor belt 23a is formed using a material having durability against the firing temperature of the unfired film FA. In this embodiment, as an example, a configuration in which a conveyance belt 23a formed of PBO (polyparaphenylene benzoxazole) fibers is used will be described as an example. However, the present invention is not limited to this, and stainless steel or polyimide (kapton ( The conveyor belt 23a may be formed of other materials such as a registered trademark)).

  The conveying belt 23a is stretched between the driving roller 23b and the driven roller 23c so as to be substantially parallel to the XY plane in a tensioned state. In this state, a placement surface 23f on which the unfired film FA is placed is formed on the + Z side of the transport belt 23a. The placement surface 23f is formed flat. For this reason, it is possible to uniformly support the entire unfired film FA.

  A portion of the transport belt 23a that is discharged from the carry-out port 20b is rewound in the −Y direction by the drive roller 23b and passes through the base frame BF. In addition, the structure which arrange | positioned the washing | cleaning part (not shown) which wash | cleans the mounting surface 23f of the conveyance belt 23a in the base frame BF may be sufficient.

  The driving roller 23 b is disposed at the + Y side end inside the chamber 21. The drive roller 23b is formed in a cylindrical shape, for example, and is disposed in parallel with the X direction. The drive roller 23b is provided with a rotary drive device such as a motor. The driving roller 23b is provided so as to be rotatable around an axis parallel to the X direction by the rotation driving device. As the drive roller 23b rotates, the transport belt 23a rotates clockwise in FIG. 2, and moves so as to circulate including the transport region TR of the unfired film FA. By the movement of the transport belt 23a, the unfired film FA and the fired film FB are transported in the + Y direction while being placed on the placement surface 23f of the transport belt 23a.

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

  The tension roller 23d is disposed on the + Z side of the driven roller 23c. The tension roller 23d is arranged in parallel to the X direction and is provided to be rotatable around the X axis. The tension roller 23d is provided to be movable up and down in the Z direction. The tension roller 23d can sandwich the unfired film FA with the driven roller 23c. The tension roller 23d can rotate with the unfired film FA interposed therebetween.

  The tension roller 23e is disposed on the + Z side of the drive roller 23b. The tension roller 23e is disposed in parallel with the X direction, and is provided to be rotatable around the X axis. The tension roller 23e is provided to be movable up and down in the Z direction. The tension roller 23e can sandwich the fired film FB with the driving roller 23b. The tension roller 23e can rotate with the fired film FB interposed therebetween.

  The tension rollers 23d and 23e sandwich the unfired film FA and the fired film FB between the driven roller 23c and the drive roller 23b, respectively, so that the unrolled film FA and the fired film FB are sandwiched. The tension between the two places is cut from the external tension. Thereby, it is possible to prevent an excessive load from being applied to the unfired film FA and the fired film FB. The tension rollers 23d and 23e can be adjusted so that no tension is applied to the unfired film FA and the fired film FB disposed in the chamber 21.

  The belt cooling unit 24 is disposed on the bottom 21 b of the chamber 21 and cools the conveyance belt 23 a that moves in the chamber 21. The belt cooling unit 24 is formed in a rectangular box shape, and a plurality of the belt cooling units 24 are arranged in the moving direction (+ Y direction) of the transport belt 23a. The belt cooling unit 24 has a through hole 24a. The through hole 24a is formed so as to penetrate the inside of the belt cooling unit 24 in the X direction. One end portion in the X direction of the through hole 24a is connected to the exhaust portion 25 via a pipe 24b. The other end in the X direction of the through hole 24a is opened to the outside.

  In this embodiment, for example, as shown in FIG. 6B, the belt cooling unit 24 in which the pipe 24b is connected to the + X side end of the through hole 24a, and the pipe 24b to the −X side end of the through hole 24a. The connected belt cooling units 24 are alternately arranged in the Y direction. However, the arrangement is not limited to this, and other arrangements may be used. Further, the plurality of belt cooling units 24 may be integrated.

  The exhaust unit 25 sucks the through hole 24a of the belt cooling unit 24 and discharges the sucked gas to the outside. The exhaust part 25 has a first exhaust part 25a and a second exhaust part 25b. As an example, the first exhaust part 25 a is connected to the through hole 24 a of the belt cooling part 24 disposed on the −Y side from the center in the Y direction of the chamber 21. The second exhaust part 25b is connected to a through hole 24a of the belt cooling part 24 disposed on the + Y side from the center in the Y direction of the chamber 21. By the operation of the first exhaust part 25a and the second exhaust part 25b, the external gas passes through the through hole 24a in the X direction.

  When the heating unit 22 is heated, the temperature of the transport belt 23a rises and may exceed the durable temperature of the material constituting the transport belt 23a. By the operation of the exhaust unit 25 (the first exhaust unit 25a and the second exhaust unit 25b), the external gas passes through the through hole 24a in the X direction and is exhausted, and the heat inside the belt cooling unit 24 is exhausted accordingly. Is done. Therefore, when the temperature of the conveyance belt 23a rises, the heat is discharged to the outside through the belt cooling unit 24, and thus the conveyance belt 23a is cooled. In this way, by cooling the transport belt 23a by the belt cooling unit 24, the temperature rise of the transport belt 23a is suppressed.

  The removal unit 26 is disposed on the −Y side of the chamber 21. The removal unit 26 removes the solvent from the unsintered film FA prior to firing the unsintered film FA. The removing unit 26 includes a container 26a, a removing liquid 26b, and guide rollers 26c to 26f. The upper part (+ Z side) of the container 26a is released. As the removal liquid 26b, for example, water is used, and is exchangeably stored in the container 26a. The guide rollers 26c to 26f are folded and guided so that the unsintered film FA sent out from the sending-out part 60 passes through the removal liquid 26b of the container 26a. When the unfired film FA is immersed in the removal liquid 26b, a part of the solvent contained in the unfired film FA is dissolved in the removal liquid 26b, and the removal liquid 26b is absorbed by the unfired film FA. Thereby, the strength of the unfired film FA is improved.

[Removal unit (etching equipment)]
As shown in FIG. 2, the removal unit 30 includes a chamber 31, an immersion unit 32, a cleaning unit 33, a liquid draining unit 34, and a transport unit 35. The chamber 31 has a carry-in port 30a for carrying in the fired film FB and a carry-out port 30b for carrying out the porous resin film F. The chamber 31 accommodates an immersion unit 32, a cleaning unit 33, a liquid draining unit 34, and a transport unit 35.

  The immersion part 32 performs etching on the fired film FB to remove fine particles contained in the fired film FB to form the porous resin film F. In the immersion part 32, the fine particles are removed by immersing the fired film FB in an etching solution Q1 such as a hydrofluoric acid solution capable of dissolving or decomposing the fine particles. In the immersion part 32, a supply part 32a that discharges and supplies the etching liquid Q1 from the + Y side of the fired film FB, and a supply part 32b that discharges and supplies the etching liquid Q1 from the -Y side of the fired film FB. Is provided. In addition, a reservoir (not shown) capable of storing the etching solution Q1 is provided. Since the liquid contained in the dipping unit 32 and the cleaning unit 33 is different, a water supply roller (to be described later) may be provided at a position before being carried out from the dipping unit 32. The water absorbing roller is disposed on at least one of the + Z side and the −Z side with respect to the porous resin film F, preferably both.

  The cleaning unit 33 cleans the etched porous resin film F. The cleaning unit 33 is disposed on the + Y side of the immersion unit 32 (in front of the transport direction of the porous resin film F). The cleaning unit 33 includes a supply unit (not shown) that supplies a cleaning liquid. Moreover, you may have a collection | recovery part (not shown) etc. which collect | recover the waste liquid after wash | cleaning the porous resin film F. FIG.

  The liquid drain part 34 removes the liquid adhering to the washed porous resin film F. You may perform preliminary drying etc. The liquid draining part 34 is disposed on the + Y side of the cleaning part 33 (in front of the transport direction of the porous resin film F). The liquid draining part 34 is provided with a water absorption roller or the like. By bringing the water absorption roller into contact with the porous resin film F, the liquid adhering to the porous resin film F can be absorbed while the porous resin film F is conveyed. The arrangement of the water absorption roller in the conveying direction is not particularly limited as long as it is before being carried out from the liquid draining portion 34. Further, the water absorbing roller is disposed on at least one of the + Z side and the −Z side, preferably both, with respect to the porous resin film F.

  The transport unit 35 transports the fired film FB and the porous resin film F across the immersion unit 32, the cleaning unit 33, and the liquid draining unit 34. The conveyance unit 35 includes a conveyance belt 35a, a driving roller 35b, and a driven roller 35c. In addition to the driving roller 35b and the driven roller 35c, a support roller that supports the conveyance belt 35a may be disposed inside the immersion unit 32, the cleaning unit 33, and the liquid draining unit 34.

  The transport belt 35a transports the fired film FB (or the etched porous resin film F) in the + Y direction. The transport belt 35a is formed in a belt shape and is arranged to be long in the Y direction along the transport direction. The conveyor belt 35a is formed in an annular shape and is disposed along the Y direction. The conveyance belt 35a is formed using a material having durability with respect to the etching solution Q1, such as aramid. Note that the surface of the conveyor belt 35a may be coated with a fluororesin or the like. Thereby, the durability against the etching solution is further improved. For example, the entire surface of the transport belt 35a is formed in a net shape, and an etching solution can pass through the transport belt 35a. The conveyor belt 35a is stretched between the driving roller 35b and the driven roller 35c in a state having tension so as to be substantially parallel to the XY plane. The porous resin film F is placed on the transport belt 35a and transported.

  The drive roller 35 b is disposed at the + Y side end inside the chamber 31. The drive roller 35b is formed in a cylindrical shape, for example, and is disposed in parallel with the X direction. The drive roller 35b is provided with a rotation drive mechanism (not shown), for example. With this rotational drive mechanism, the drive roller 35b can rotate around an axis parallel to the X direction.

  As the driving roller 35b rotates, the transport belt 35a rotates in the clockwise direction in FIG. 2, and is circulated and supplied to the transport region of the fired film FB. In addition, the transport belt 35a is circulated and supplied, so that the fired film FB placed on the transport belt 35a is transported in the + Y direction.

  The driven roller 35 c is disposed at the −Y side end inside the chamber 31. The driven rollers 35d to 35f are disposed on the −Z side of the driven roller 35c and the driving roller 35b, respectively. The driven rollers 35c to 35f are formed in a cylindrical shape, for example, and are arranged in parallel to the X direction. The driven roller 35c is formed to have the same diameter as the driving roller 35b, and is disposed so that the position (height position) in the Z direction is substantially equal to the driving roller 35b. The driven rollers 35c to 35f are provided so as to be rotatable around an axis parallel to the X direction. The driven rollers 35c to 35f rotate following the rotation of the transport belt 35a.

  The driven rollers 35d to 35f adjust the tension of the conveyor belt 35a and are formed to have the same diameter, for example. The driven roller 35f is provided so as to be movable (movable up and down) in the Z direction by a drive mechanism (not shown). The tension of the conveyor belt 35a can be adjusted by moving the driven roller 35f up and down.

The removal unit 30 is not limited to removing fine particles 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. Such an organic material is not particularly limited as long as it decomposes at a lower temperature than polyimide. For example, resin fine particles made of a linear polymer or a known depolymerizable polymer can be mentioned. A normal linear polymer is a polymer in which a polymer molecular chain is randomly cleaved during thermal decomposition, and a depolymerizable polymer is a polymer in which the polymer is decomposed into monomers during thermal decomposition. Any of them disappears from the fired film FB by decomposing into low molecular weight substances or CO ₂ . In this case, the decomposition temperature of the fine particles is preferably 200 to 320 ° C, and 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 solution, and the range of selection of the baking conditions in the baking unit 20 is widened. If the decomposition temperature is less than 320 ° C., only the fine particles can be lost without causing thermal damage to the fired film FB.

[Winding part (2)]
FIG. 7 is a perspective view schematically showing the configuration of the removal unit 30 on the + Y side.
As shown in FIG. 7, on the + Y side of the removal unit 30, a carry-out port 30 b for carrying out the porous resin film F is provided. The porous resin film F carried out from the carry-out port 30 b is taken up by the take-up unit 80.

  The winding unit 80 is configured such that the shaft member SF is mounted on the bearing 81. The shaft member SF winds up the porous resin film F carried out from the carry-out port 30b to form the roll body RF. The shaft member SF is provided so as to be detachable from the bearing 81. When the shaft member SF is mounted on the bearing 81, the shaft member SF 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) that rotates the shaft member SF attached to the bearing 81. The porous resin film F is wound up by rotating the shaft member SF by the drive mechanism. By removing the shaft member SF from the bearing 81 in a state where the roll body RF is formed, the roll body RF can be collected.

[Production method]
Next, an example of the operation | movement which manufactures the porous resin film F using the manufacturing system SYS comprised as mentioned above is demonstrated. 8A to 8F are diagrams illustrating an example of a manufacturing process of the porous resin film F. FIG.

  First, an unfired film FA is formed in the coating unit 10. In the coating unit 10, the base material feed roller 11 a is rotated to send out the transport base material S, the transport base material S is hung on the support rollers 11 b to 11 d, and then wound around the base material take-up roller 11 e. Thereafter, the transport base material S is sequentially sent out from the base material feed roller 11a and is wound up by the base material take-up roller 11e.

  In this state, the first nozzle 12 is disposed at the discharge position P1, and the discharge port 12a is directed in the + Y direction. As a result, the discharge port 12a is directed to the portion of the transport substrate S that is supported by the support roller 11b. Thereafter, the first coating liquid EQ1 is discharged from the discharge port 12a. The first coating liquid EQ1 is discharged from the discharge port 12a in the + Y direction, reaches the transport base S, and is applied onto the transport base S as the transport base S moves. As a result, as shown in FIG. 8A, the first coating film F1 is formed on the transport substrate S by the first coating liquid EQ1.

  Subsequently, the second nozzle 12 is disposed at the discharge position P2, and the discharge port 13a is directed in the −Z direction. As a result, the discharge port 13a is directed to the portion of the transport substrate S that is supported by the support roller 11c. Thereafter, the second coating liquid EQ2 is discharged from the discharge port 13a. The second coating liquid EQ2 is discharged in the −Z direction from the discharge port 13a, reaches the first coating film F1 formed on the transport substrate S, and then moves along with the movement of the transport substrate S. It is applied on the coating film F1. As a result, as shown in FIG. 8B, a second coating film F2 made of the second coating liquid is formed on the first coating film F1. The first coating film F1 and the second coating film F2 contain fine particles A2 in the resin material A1 at different volume ratios. The content ratio of the fine particles is set to be larger in the first coating film F1 than in the second coating film F2.

  The first coating liquid EQ1 and the second coating liquid EQ2 are applied with the discharge ports 12a and 13a facing the portions of the transport base S supported by the support rollers 11b and 11c. The forces acting on the transport substrate S when the EQ1 and the second coating liquid EQ2 reach the transport substrate S are received by the support rollers 11b and 11c. For this reason, generation | occurrence | production of the bending of a conveyance base material S, a vibration, etc. is suppressed, and the 1st coating film F1 and the 2nd coating film F2 are stably formed on the conveyance base material S with uniform thickness.

  Subsequently, when the transport substrate S moves and the laminated portion of the first coating film F1 and the second coating film F2 is carried into the chamber 14a of the drying unit 14, the first coating film F1 and the first coating film F1 in the drying unit 14 are transferred. 2 Dry the coating film F2. In the drying unit 14, the first coating film F1 and the second coating film F2 are heated at a temperature of, for example, about 50 ° C. to 100 ° C. using the heating unit 14b. If it is this temperature range, the 1st coating film F1 and the 2nd coating film F2 can be heated, without distortion, a deformation | transformation, etc. generating to the conveyance base material S. By drying the laminate of the first coating film F1 and the second coating film F2, an unfired film FA is formed as shown in FIG. 8C. A part of the solvent remains in the unfired film FA.

  In the present specification, the laminate means an unfired film composed of the first coating film F1 and the second coating film F2. When the porous imide-based resin film according to the present invention is formed, the first liquid and the second liquid are formed when the same kind of resin is used in each of polyamic acid, polyimide, polyamideimide, and polyamide. The unfired film (or porous imide-based resin film) composed of the first coating film F1 and the second coating film F2 is substantially one layer, but the unfired film (or the empty film) having a different content of fine particles. In this specification, including the case where the same kind of resin is used for the first liquid and the second liquid, the laminate is referred to as a laminate. .

  Subsequently, when the transport substrate S moves and the leading end portion of the unfired film FA reaches the support roller 11d (peeling portion 15), the leading end portion is moved by, for example, an operator's manual operation. Peel from. In this embodiment, for example, PET is used as the material of the transport substrate S. Therefore, when the uncoated film FA is formed by drying the first coating film F1 and the second coating film F2, from the transport substrate S. Since it becomes easy to peel off, the operator can easily peel off.

  After peeling off the tip portion of the unfired film FA, the transport substrate S continues to move, and the first coating film F1 is formed by the first nozzle 12. Further, the second coating film F <b> 2 is subsequently formed by the second nozzle 13, and the unfired film FA is formed by the drying unit 14. Thereby, the unsintered film FA is formed in a band shape, and the length of the unsintered film FA carried out from the drying unit 14 to the + Y side is gradually increased. The operator continues to peel off the unfired film FA at the peeling portion 15. When the tip of the peeled unfired film FA reaches a length that reaches the shaft member SF of the winding unit 50, the operator manually places the unfired film FA on the unloading roller 11f and unfires the unfired film FA. The tip portion of the film FA is attached to the shaft member SF. Thereafter, as the unfired film FA is sequentially formed and peeled off, the winding member 50 rotates the shaft member SF. Thereby, the peeled unfired film FA is sequentially carried out of the coating unit 10 and wound up by the shaft member SF of the winding unit 50 to form the roll body R. As shown in FIG. 8D, the unfired film FA constituting the roll body R is peeled from the transport substrate S, and both the front surface and the back surface are exposed.

  In addition, about the operation | work which peels the front-end | tip part of unfired film | membrane FA, and the operation | work which mounts the peeled front-end | tip part to shaft member SF, it is not restricted to the mode which an operator performs manually, for example, automatically using a manipulator etc. You may go on. Further, a release layer may be formed on the surface of the transport substrate S in order to improve the peelability of the unfired film FA.

  After the unfired film FA having a predetermined length is wound around the shaft member SF, the unfired film FA is cut and the shaft member SF is removed from the bearing 51 together with the roll body R. Then, a new shaft member SF is mounted on the bearing 51 of the winding unit 50, and the cut end portion of the unfired film FA is attached to the shaft member SF and rotated to continuously form the unfired film FA. A simple roll body R can be created.

  On the other hand, for example, the operator conveys the shaft member SF removed together with the roll body R from the bearing 51 to the delivery unit 60 and attaches it to the bearing 61. The conveying operation and mounting operation of the shaft member SF may be automatically performed using a manipulator, a conveying device, or the like. After mounting the shaft member SF on the bearing 61, the unfired film FA is sequentially pulled out from the roll body R by rotating the shaft member SF, and the unfired film FA is carried into the removing portion 26 of the firing unit 20.

  In the removing unit 26, the unfired film FA is conveyed by the guide rollers 26c to 26f, and is taken out after being immersed in the removing liquid 26b in the container 26a for a predetermined period. By immersing the unfired film FA in the removal liquid 26b, the solvent remaining in the unfired film FA is dissolved into the removal liquid 26b, and the removal liquid 26b is absorbed by the portion containing the solvent. Thereby, the solvent is removed from the unfired film FA, and the strength of the unfired film FA is increased. The unsintered film FA taken out from the removal liquid 26 b is carried into the chamber 21. In addition, when carrying the front-end | tip of the unbaked film | membrane FA in the removal part 26 and the chamber 21, each operator may carry out manually and may carry out automatically using a manipulator etc., respectively. Further, the untreated film FA taken out from the removal liquid 26b may be pressurized by a roller or the like before being carried into the chamber 21.

  The unsintered film FA carried into the chamber 21 is placed on the transport belt 23a. In this state, the transport belt 23a moves so as to circulate including the transport region TR, whereby the unsintered film FA is transported through the transport region TR in the + Y direction. The tension may be adjusted using the tension rollers 23d and 23e. For example, the atmosphere around the unfired film FA is adjusted to an atmosphere of an inert gas such as nitrogen gas by the atmosphere adjusting unit 21c. In this state, the unfired film FA is baked using the heating unit 22 while the unfired film FA is conveyed. In this case, the unfired film FA is heated from the surface side (+ Z side in FIG. 6) by the heating unit 22.

  Although the temperature at the time of baking changes with structures of the unbaked film | membrane FA, it is preferable that it is about 120 to 375 degreeC, More preferably, it is 150 to 350 degreeC. Moreover, when the organic material is contained in the fine particles, it is necessary to set the temperature lower than the thermal decomposition temperature. In the case where the coating solution contains polyamic acid, it is preferable to complete imidization in this baking. However, the unfired film FA is composed of polyimide, polyamideimide or polyamide, and the firing unit 20 applies the unfired film FA to the unfired film FA. This does not apply when high-temperature treatment is performed.

  In addition, for example, when the coating solution contains polyamic acid and / or polyimide, the firing conditions include a method of raising the temperature from room temperature to 375 ° C. over 3 hours and then holding the temperature at 375 ° C. for 20 minutes, or from room temperature to 50 ° C. Stepwise heating may be performed such that the temperature is gradually raised to 375 ° C. in increments (each step is held for 20 minutes) and finally held at 375 ° C. for 20 minutes. Further, the end of the unfired film FA may be fixed to a SUS mold or the like to prevent deformation.

  By such firing, a fired film FB is formed as shown in FIG. In the fired film FB, fine particles A2 are contained inside the resin layer A3 that has been imidized or subjected to high temperature treatment. The film thickness of the fired film FB can be obtained, for example, by measuring and averaging the thickness of a plurality of locations with 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.

  In firing, there is a period in which the composition of the unfired film FA changes and becomes temporarily brittle. In this embodiment, the unsintered film FA is not transported with tension, but is placed on the transport belt 23a and transported. It is possible to prevent the fired film FA from being broken or cut.

  Further, after the unfired film FA is fired, the transport belt 23a may be cooled. In this case, the through hole 24a of the belt cooling unit 24 is sucked by the exhaust unit 25 (the first exhaust unit 25a and the second exhaust unit 25b). Thereby, the external gas passes through the through hole 24a in the X direction and is discharged to the outside. Accordingly, the heat of the belt cooling unit 24 is discharged to the outside together with the gas. Therefore, the heat of the conveyance belt 23a is discharged to the outside through the belt cooling unit 24, and the conveyance belt 23a is cooled.

  When the fired film FB formed in the firing unit 20 is unloaded from the firing unit 20, it is carried into the removal unit 30 without being wound up. In addition, when carrying in the removal unit 30 the front-end | tip part of the baking film | membrane FB, an operator may carry out manually and may carry out automatically using a manipulator etc.

  The fired film FB carried into the removal unit 30 is placed on the transport belt 35a and transported in the + Y direction according to the rotation of the transport belt 35a. In the removal unit 30, the fine particles A <b> 2 are first removed in the immersion part 32 along with the conveyance of the fired film FB. When silica, for example, is used as the material of the fine particles A2, the fired film FB is immersed in an etching solution such as low-concentration hydrogen fluoride water in the immersion part 32. Thereby, the fine particles A2 are dissolved and removed in the etching solution, and as shown in FIG. 8F, the porous resin film F in which the porous portion A4 is included in the resin layer A3 is formed.

    Thereafter, the porous resin film F is sequentially carried into the cleaning unit 33 and the drying unit 34 according to the rotation of the conveyance belt 35a. In the cleaning unit 33, the porous resin film F is cleaned by the cleaning liquid, and liquid draining is performed. Moreover, in the drying part 34, the porous resin film F after draining is heated, and the cleaning liquid is removed. Then, the porous resin film F is unloaded from the removal unit 30 and wound up by the shaft member SF of the winding unit 80.

  As described above, the firing unit 20 according to the present embodiment has the belt-like transport belt 23a that can move by placing the unfired film FA formed from a liquid containing a predetermined resin material and fine particles, and the transport belt 23a. And the heating unit 22 that bakes while transporting the unfired film FA, so that the unfired film FA is broken even during a period in which the composition of the unfired film FA changes and becomes temporarily brittle during firing. Or being cut off. Thereby, damage to the unfired film FA can be prevented.

  Further, since the manufacturing system SYS according to the present embodiment includes such a firing unit 20, 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 (porous) The three steps of forming the conductive resin film F) can be performed in a series of flows, and a high-quality fired film FB can be formed in firing the unfired film FA. Thereby, the high quality porous resin film F can be manufactured with high efficiency.

[Modification]
FIG. 9 is a diagram illustrating an example of a firing unit according to a modification. FIGS. 9A and 9B are views showing a part of the firing unit 20A as an example. FIGS. 9C and 9D are views showing a part of the firing unit 20B as another example.

  As shown in FIGS. 9A and 9B, the firing unit 20 </ b> A may have a pressing member 28. The holding member 28 holds both sides of the unfired film FA in the direction (X direction) intersecting the moving direction (Y direction) toward the conveying belt 23a. The pressing member 28 is disposed, for example, in the chamber 21 in the vicinity of the carry-in port 20a. FIG. 9B shows an example in which the pressing members 28 are arranged at both ends in the X direction of the unfired film FA. However, the present invention is not limited to this, and one side of the unfired film FA in the X direction is shown. The structure which hold | suppresses only the edge of this may be sufficient. Further, as shown in FIGS. 9A and 9B, the pressing member 28 includes a base portion 28a and a roller 28b, and is configured to press the unsintered film FA by the roller 28b. In this configuration, the unfired film FA is transported in a state where both ends in the X direction are pressed against the transport belt 23a by the pressing member 28. Thereby, it can prevent that the both ends of the X direction of unbaking film | membrane FA curve. Further, since the roller 23b rotates with the movement of the transport belt 23a and the unfired film FA, it is possible to suppress the edge of the unfired film FA while suppressing the tension on the unfired film FA.

  Moreover, as shown in FIGS. 9C and 9D, the firing unit 20 </ b> B may have a pressing member 29. The pressing member 29 has a base portion 29a and a strip portion 29b. The pressing member 29 is provided in a state where the base portion 29 a is disposed outside the chamber 21 and the belt-like portion 29 b is inserted into the chamber 21 from the outside of the chamber 21 via the carry-in port 20 a. The strip portion 29b presses both ends of the unfired film FA in the direction (X direction) intersecting the moving direction (Y direction) toward the transport belt 23a. In this configuration, the unfired film FA is transported in a state where both ends in the X direction are pressed against the transport belt 23 a by the pressing member 29. Even in this case, it is possible to prevent the both ends in the X direction of the unfired film FA from being curved. FIG. 9D shows an example in which the strip portion 29b is disposed at both ends in the X direction of the unfired film FA. However, the present invention is not limited to this, and the X direction of the unfired film FA is shown. The structure which hold | suppresses only one edge side of may be sufficient.

FIG. 10 is a diagram illustrating an example of a firing unit 20C according to another modification.
As shown in FIG. 10, in the firing unit 20 </ b> C, a belt heating unit (conveying member heating unit) 22 </ b> C is provided on the bottom 21 b of the chamber 21. The belt heating unit 22C is disposed on the back side (−Z side) of the transport belt 23g, and heats the unfired film FA from the back side through the transport belt 23g. The belt heating unit 22C has a plurality of heaters arranged side by side in the Y direction. As such a heater, for example, an infrared heater is used as in the above embodiment.

  In this case, the conveyance belt 23g is formed of a metal material such as stainless steel. By the operation of the belt heating unit 22C, the conveyance belt 23g is heated, and the unsintered film FA is heated and baked by the conveyance belt 23g. In addition, in FIG. 10, although the structure by which a heating part is not provided in the ceiling part 21a side is shown, it is not limited to this, The heating part 22 grade | etc., Described in the said embodiment is provided in the ceiling part 21a side. May be. In addition, about the conveyance belt 23g formed with metal materials, such as stainless steel, it is not necessary to provide a belt cooling part as shown, for example in FIG. 10, and it may cool by providing a belt cooling part.

FIG. 11 is a diagram illustrating an example of a manufacturing system SYS2 according to another modification.
As shown in FIG. 11, in the production system SYS2, the removal unit 30 is not provided with the transport unit 35 for placing and transporting the fired film FB and the porous resin film F. It is configured to carry directly. In the immersion part 32, for example, the etching solution Q1 is stored in the container 32p, and the fired film FB is immersed in the etching solution Q1 by the guide roller 32q.

  In the manufacturing system SYS2, the solvent contained in the unfired film FA is removed in the removing unit 26 before firing in the firing unit 20. Thereby, the strength of the unfired film FA is improved, and the strength of the fired film FB and the porous resin film F thereafter is also improved. Therefore, even if it is a case where it conveys with the roller R directly, without mounting on the conveyance belt 35a, the baking film | membrane FB and the porous resin film F become difficult to damage. Therefore, the fired film FB and the porous resin film F can be efficiently conveyed.

  Moreover, in the said embodiment, although the structure which attaches / detaches shaft member SF to the bearings 51 and 81 was mentioned as an example as the winding parts 50 and 80, it did not limit to this, For example, as shown in FIG. A simple winding device 90 may be used. Hereinafter, a case where the winding device 90 is used instead of the winding unit 50 will be described as an example.

  As illustrated in FIG. 12, the winding device 90 includes a frame 91, a shaft member SF, a bearing 92, a drive unit 93, relay rollers 94 a to 94 e, and a roller support unit 95. The frame 91 supports each part of the shaft member SF, the bearing 92, the drive unit 93, the relay rollers 94a to 94e, and the roller support unit 95.

  The shaft member SF forms the roll body R by winding up the unfired film FA carried out from the coating unit 10. The shaft member SF is detachably attached to the bearing 92. When the shaft member SF is attached to the bearing 92, the shaft member SF is supported by the bearing 92 so as to be rotatable around an axis parallel to the X direction. By removing the shaft member SF from the bearing 92 in a state where the roll body R is formed, the roll body R can be moved or recovered to another unit.

  The relay rollers 94a to 94e send the unsintered film FA to the shaft member SF while adjusting the tension of the unsintered film FA. The relay rollers 94a to 94e are formed in a cylindrical shape, for example, and are arranged in parallel to the X direction. In the present embodiment, the unsintered film FA is bridged in the order of the relay rollers 94a, 94b, 94c, 94d, and 94e, but is not limited to this, and some relay rollers may not be used. Note that at least one of the relay rollers 94 a to 94 e 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. Moreover, the structure which rotates the relay roller 94b around the axis line AX parallel to an X-axis by the roller support part 95 may be sufficient. In this case, it is possible to keep the tension of the unfired film FA constant by feeding back the amount (distance) by which the relay roller 94b moves (rotates) to the winding speed of the bearing 92. Further, the load on the relay roller 94b may be changed by moving a movable weight (not shown) located on the −Y side of the relay roller 94b and arranged via a fulcrum shaft. In this case, it is possible to adjust the tension of the unfired film FA by adjusting the load applied to the relay roller 94b with the weight.

  The relay rollers 94a to 94e are not limited to being arranged 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 those having a crown such as a taper type, a radial type, and a concave type may be used.

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

[Separator]
Next, the separator 100 according to the embodiment will be described. FIG. 13 is a schematic view showing an example of the lithium ion battery 200, and shows a state in which a part thereof is cut open. As shown in FIG. 13, the lithium ion battery 200 includes a metal case 201 that also serves as a positive electrode terminal, and a negative electrode terminal 202. Inside the metal case 201, a positive electrode 201a, a negative electrode 202a, and a separator 100 are provided and are immersed in an electrolyte solution (not shown). The separator 100 is disposed between the positive electrode 201a and the negative electrode 202a, and prevents electrical contact between the positive electrode 201a and the negative electrode 202a. As the positive electrode 201a, a lithium transition metal oxide is used, and as the negative electrode 202a, for example, lithium, carbon (graphite), or the like is used.

  The porous resin film F described in the above embodiment is used as the separator 100 of the lithium ion battery 200. In this case, for example, by setting the surface on which the first coating film F1 is formed on the negative electrode 202a side of the lithium ion battery, the battery performance can be improved. In FIG. 13, the separator 100 of the square lithium ion battery 200 is described as an example, but the present invention is not limited to this. The porous resin film F can be used for any type of lithium ion battery separator such as a cylindrical type or a laminate type. In addition to the separator of the lithium ion battery, 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.

The embodiment has been described above, 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 embodiment, the structure in which the unfired film FA is immersed in the removing liquid 26b for a predetermined time in the removing unit 26 before firing in the chamber 21 has been described as an example. However, the present invention is not limited thereto. . For example, instead of immersing in the removal liquid 26b, it may be allowed to stand for a predetermined time. In this case, the solvent is removed from the unfired film FA, and the edge of the unfired film FA in the X direction can be prevented from being curved during firing.

  For example, in addition to the structure of the said embodiment, the post-processing unit which performs a post-process with respect to the porous resin film F formed with the removal unit 30 may be provided. As such a post-processing unit, for example, an antistatic unit that performs static elimination treatment on the porous resin film F can be cited. As the antistatic unit, for example, a static eliminator such as an ionizer is mounted.

  Further, as the post-processing unit, for example, a chemical etching unit (not shown) for removing a part of the porous resin film F can be used. The chemical etching unit has, for example, the same configuration as that of the removal unit 30 of the above embodiment, and an alkaline solution or the like is used as the treatment liquid instead of the hydrofluoric acid solution. By immersing the porous resin film F in the treatment liquid for a predetermined time, the inside of the porous portion A4 is removed. In this case, the burrs of the porous portion A4 can be removed and the connectivity is ensured.

  Moreover, when removing a part of porous resin film F by such a chemical etching unit, it is not limited to a chemical etching method. 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 (eg, alumina (hardness 9), etc.) is dispersed in a liquid, and this is the surface of an aromatic polyimide film. Or a method of treating the surface of the polyimide film by irradiating at a speed of 30 m / s to 100 m / s. These methods can be applied to both the case before removing fine particles from the fired film FB in the removing unit 30 and the case after removing fine particles. In addition, as a physical method that can be applied only when it is performed after removing fine particles, after being pressure-bonded to a backing film (for example, a polyester film such as a PET film) whose surface is wetted with a liquid, it is not dried or dried, and then porous. It is also possible to employ a method of peeling the conductive resin film F from the mount film. Due to the surface tension or electrostatic adhesion of the liquid, the porous resin film F is peeled off from the mount film in a state where only the surface layer of the porous resin film F is left on the mount film.

  For example, in the above embodiment and the modification, the case where the unfired film FA is formed using two types of coating liquids having different fine particle contents has been described as an example, but the present invention is not limited to this. An unsintered film may be formed with various types of coating solutions. In this case, one of the first nozzle 12 and the second nozzle 13 may not be used, and one nozzle may be omitted. When one nozzle is omitted, it is preferable to omit the first nozzle 12 and use the second nozzle 13.

  Moreover, although the said embodiment and modification demonstrated and demonstrated as an example the structure by which the coating | coated unit 10, the baking unit 20, and the removal unit 30 were arrange | positioned 1 each, it is not limited to this. For example, a plurality of at least one of the above units may be provided. In this case, for example, by arranging many units with a small amount (eg, length, etc.) of the unfired film FA, fired film FB or porous resin film F that can be processed per unit time, the entire manufacturing system SYS Manufacturing efficiency can be increased.

  Moreover, in the said embodiment and modification, each unit of the application | coating unit 10, the baking unit 20, and the removal unit 30 is each film | membrane of unbaked film | membrane FA, the baked film FB, or the porous resin film | membrane F along a Y direction. Although the case of carrying was described as an example, the present invention is not limited to this. For example, any unit may transport the film in the X direction, the Y direction, the Z direction, or a combination direction thereof, or the transport direction may be appropriately changed within one unit.

  Moreover, although the said embodiment and modification demonstrated and demonstrated as an example the case where three processes of application | coating in the application | coating unit 10, baking in the baking unit 20, and removal in the removal unit 30 were performed, it does not limit to this. Absent. For example, when polyimide, polyamideimide, or polyamide is used as the material of the coating film, baking is not necessary. For this reason, when baking is not performed, for example, by providing a winding device, a feeding device, and the like between the baking unit 20 and the removal unit 30, the unfired film FA formed by the coating unit 10 is replaced with the baking unit 20. It can be carried into the removal unit 30 without intervention. In addition, when firing is not performed, a production system for producing a porous imide resin film is a coating system in which a liquid containing polyamic acid, polyimide, polyamideimide or polyamide and fine particles is applied to a substrate to form an unfired film. It can be set as the manufacturing system containing a unit and the removal unit which removes the said microparticles | fine-particles from the said unbaking film | membrane peeled from the said base material in the said coating unit or the said coating unit outside. In addition, when baking is not performed, after carrying out the porous resin film | membrane F from the removal unit 30 which removes microparticles | fine-particles, you may perform the above-mentioned post-baking process process. Moreover, when using a chemical etching unit, you may pass a chemical etching unit before a post-baking process. In this case, the post-bake treatment step may be performed by, for example, a heating unit provided in the chemical etching unit.

  Moreover, although the said embodiment and modification demonstrated and demonstrated the structure which forms the porous resin film F by what is called a roll-to-roll system as an example, it is not limited to this. For example, when the porous resin film F is unloaded from the removal unit 30 (or chemical etching unit) after the processing in the removal unit 30 (or chemical etching unit) is completed, the winding unit 80 does not wind the porous resin film F. You may cut | disconnect by predetermined length and collect | recover what was cut | disconnected.

SYS, SYS2 ... manufacturing system F ... porous resin film FA ... unfired film FB ... fired film TR ... transport area 10 ... coating unit 20, 20A, 20B, 20C ... fired unit 21c ... atmosphere adjusting part 22 ... heating part 22a ... Heater 22C ... Belt heating unit 23 ... Conveying unit 23a, 23g ... Conveying belt 23b ... Drive roller 23c ... Driven roller 23f ... Placement surface 24 ... Belt cooling unit 25 ... Exhaust unit 26 ... Removing unit 28, 29 ... Holding member 30 ... Removal unit 100 ... Separator 200 ... Lithium ion battery

Claims (20)

A belt-shaped transport member that can move by placing an unfired film formed from a liquid containing polyamic acid, polyimide, polyamideimide, or polyamide, and fine particles;
And a firing unit that fires the unfired film while being transported by the transport member.   The firing apparatus according to claim 1, wherein the conveying member has a flat surface on which the unfired film is placed.   The firing apparatus according to claim 1, wherein the conveying member is formed of PBO fiber, stainless steel, or polyimide.   The firing apparatus according to any one of claims 1 to 3, wherein the transport member is formed in an annular shape and moves so as to circulate including a transport region of the unfired film.   The said baking part has a heating part which heats the said unbaking film | membrane from the surface side of the said unbaking film | membrane, or the back surface side of the said unbaking film | membrane via the said conveyance member. The baking apparatus of Claim 1.   The firing apparatus according to claim 5, wherein the heating unit includes a conveyance member heating unit that heats the conveyance member.   The said baking part is a baking apparatus of any one of Claims 1-6 which has a cooling part which cools the said conveyance member.   The firing apparatus according to claim 1, wherein the firing section includes an atmosphere adjustment section that adjusts an atmosphere around the unfired film.   The firing according to any one of claims 1 to 8, wherein the firing part includes a pressing member that presses at least one of both end sides of the unfired film in a direction intersecting the moving direction toward the conveying member. apparatus. The unsintered film is formed of the liquid containing a predetermined solvent,
The baking apparatus of Claim 1 or Claim 2 provided with the removal part which removes the said solvent from the said unbaked film | membrane before baking of the said film. An unfired film formed from a liquid containing polyamic acid, polyimide, polyamideimide, or polyamide and fine particles is placed on a belt-shaped transport member and transported;
Firing while transporting the unsintered film by the transport member.   The firing method according to claim 11, wherein the unsintered film is transported by moving the transport member formed in an annular shape so as to circulate including a transport region of the unsintered film.   The said unsintered film is baked by heating the said unsintered film from the surface side of the said unsintered film, or from the back surface side of the said unsintered film through the said conveyance member. Firing method.   The firing method according to claim 13, wherein the unsintered film is fired by heating the transport member and heating by the heated transport member.   The firing method according to claim 11, further comprising cooling the conveying member after firing the unfired film.   The firing method according to any one of claims 11 to 15, wherein the unfired film is fired in a state in which an atmosphere around the unfired film is adjusted.   The said unbaked film is conveyed in the state in which at least one of the both ends of the direction which cross | intersects a moving direction among the said unbaked films was hold | suppressed by the said conveyance member side. The firing method described in 1. The unsintered film is formed of the liquid containing a predetermined solvent,
The firing method according to any one of claims 11 to 17, comprising removing the solvent from the unfired film prior to firing of the unfired film. A production system for producing a porous imide resin film,
The manufacturing system containing the baking apparatus of any one of Claims 1-10. A method for producing a porous imide resin film,
The manufacturing method containing the baking method of any one of Claims 11-18.

Images