WO2019044918A1 - Dispositif de formation de film polymère, procédé de formation de film polymère et procédé de production de séparateur - Google Patents

Dispositif de formation de film polymère, procédé de formation de film polymère et procédé de production de séparateur Download PDF

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Publication number
WO2019044918A1
WO2019044918A1 PCT/JP2018/031992 JP2018031992W WO2019044918A1 WO 2019044918 A1 WO2019044918 A1 WO 2019044918A1 JP 2018031992 W JP2018031992 W JP 2018031992W WO 2019044918 A1 WO2019044918 A1 WO 2019044918A1
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Prior art keywords
web
coating
slit
die
polymer film
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PCT/JP2018/031992
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English (en)
Japanese (ja)
Inventor
英樹 木ノ下
勇 佐久間
豪 守屋
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東レ株式会社
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Priority to KR1020197035760A priority Critical patent/KR20190140070A/ko
Priority to CN201880041251.0A priority patent/CN110831705A/zh
Priority to JP2018550848A priority patent/JPWO2019044918A1/ja
Publication of WO2019044918A1 publication Critical patent/WO2019044918A1/fr

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05C—APPARATUS FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05C5/00—Apparatus in which liquid or other fluent material is projected, poured or allowed to flow on to the surface of the work
    • B05C5/02—Apparatus in which liquid or other fluent material is projected, poured or allowed to flow on to the surface of the work the liquid or other fluent material being discharged through an outlet orifice by pressure, e.g. from an outlet device in contact or almost in contact, with the work
    • B05C5/0254—Coating heads with slot-shaped outlet
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409—Separators, membranes or diaphragms characterised by the material
    • H01M50/443—Particulate material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05C—APPARATUS FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05C13/00—Means for manipulating or holding work, e.g. for separate articles
    • B05C13/02—Means for manipulating or holding work, e.g. for separate articles for particular articles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05C—APPARATUS FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05C5/00—Apparatus in which liquid or other fluent material is projected, poured or allowed to flow on to the surface of the work
    • B05C5/02—Apparatus in which liquid or other fluent material is projected, poured or allowed to flow on to the surface of the work the liquid or other fluent material being discharged through an outlet orifice by pressure, e.g. from an outlet device in contact or almost in contact, with the work
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05C—APPARATUS FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05C9/00—Apparatus or plant for applying liquid or other fluent material to surfaces by means not covered by any preceding group, or in which the means of applying the liquid or other fluent material is not important
    • B05C9/04—Apparatus or plant for applying liquid or other fluent material to surfaces by means not covered by any preceding group, or in which the means of applying the liquid or other fluent material is not important for applying liquid or other fluent material to opposite sides of the work
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D1/00—Processes for applying liquids or other fluent materials
    • B05D1/26—Processes for applying liquids or other fluent materials performed by applying the liquid or other fluent material from an outlet device in contact with, or almost in contact with, the surface
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D7/00—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D7/00—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
    • B05D7/02—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials to macromolecular substances, e.g. rubber
    • B05D7/04—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials to macromolecular substances, e.g. rubber to surfaces of films or sheets
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
    • H01G11/52—Separators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/403—Manufacturing processes of separators, membranes or diaphragms
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409—Separators, membranes or diaphragms characterised by the material
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409—Separators, membranes or diaphragms characterised by the material
    • H01M50/411—Organic material
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409—Separators, membranes or diaphragms characterised by the material
    • H01M50/446—Composite material consisting of a mixture of organic and inorganic materials
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409—Separators, membranes or diaphragms characterised by the material
    • H01M50/449—Separators, membranes or diaphragms characterised by the material having a layered structure
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • the present invention applies a coating solution containing a polymer solution onto a web with a slit die to form an apparatus for forming a polymer film on one side or both sides of the web, a method for forming a polymer film, and a separator On the way.
  • Non-aqueous secondary battery lithium ion secondary battery
  • a lithium-containing transition metal oxide as a positive electrode
  • a material capable of doping and dedoping lithium as a negative electrode
  • a non-aqueous electrolytic solution as an electrolytic solution. Because of its high energy density, is used as a driving power source for portable electronic devices such as portable telephones and notebook computers and electric vehicles.
  • lithium ion secondary batteries With the reduction in size and weight of these devices and the demand for long-term use, lithium ion secondary batteries have been required to have both weight reduction, thinness, high capacity and safety.
  • various examinations which laminate a polymer film for the purpose of functional grant on a polyolefin fine porous film are made by a separator for lithium ion secondary batteries.
  • Example 1 of Patent Document 1 a PVDF copolymer solution is placed in a tank in which two Meyer bars are arranged in parallel at the bottom, and a microporous polypropylene membrane is transferred from the top of the tank into the tank at a transfer speed of 3 m / min. Apply the PVDF copolymer solution on both sides by passing between two Meyer bars, then enter the coagulation bath without contacting other equipment, rinse and dry , A polymer composite membrane separator has been obtained.
  • the PVDF layer of the polymer composite membrane separator is excellent in the adhesion to the electrode and the electrolyte retention property, and the contact between the electrode and the separator is well maintained without the pressure of the cylindrical can and the rectangular can, There is an advantage that weight reduction can be achieved by enabling Furthermore, in the production method, it is considered advantageous that the PVDF layer has a front-back symmetrical structure, and that the positive electrode interface and the negative electrode interface have similar characteristics.
  • the negative electrode On the other hand, in the lithium ion secondary battery in recent years, a further increase in thickness and capacity is required, and a silicon type such as Si / C, SiO, SiO-Si-C or the like has been proposed as the negative electrode.
  • the problem of the silicon negative electrode is volume expansion and contraction, and in order to absorb and reduce it, for example, the polymer film at the negative electrode side interface is made thicker with respect to the positive electrode side, the adhesion is strengthened, etc.
  • the polymer composite membrane separator manufacturing method described in Patent Document 1 has a problem that only a front and back symmetrical structure can be manufactured.
  • Example 1 of patent document 2 the method of coating a negative electrode slurry on both surfaces of copper foil is proposed. This conveys the web (here, copper foil) in a substantially horizontal direction, and the first coating die above the web, the lower side of the web and the second coating downstream of the first coating die A die is disposed, and the first and second coating dies are pushed in relative to the virtual transport path of the web to apply tension to the web, thereby enabling stable double-sided coating without flutter.
  • the support portion of the non-coated surface is on the upstream side of the discharge port of the coating die, so that flapping of the web can be suppressed and the clearance between the discharge port and the web can be kept uniform.
  • Japanese Patent No. 4588286 Japanese Patent Application Laid-Open No. 2016-36761 Japanese Patent No. 3162026
  • the present invention can be selectively applied to one side of a web, or in the case of double sided application, a polymer that can be applied with different composition and thickness on each side and that uniform and stable application is possible.
  • An object of the present invention is to provide a film forming apparatus, a method of forming a polymer film, and a method of manufacturing a separator.
  • the polymer film forming apparatus of the present invention for solving the above problems has the following configuration. That is, (1) In order to apply the coating liquid containing the polymer solution to the web conveyed downward, the slit die having a slit formed therein and the coating liquid coated on the surface of the web And a means for bringing a coating film into contact with a non-solvent, wherein the slit die includes the upstream die among the tips of the slit die including the upstream die tip and the downstream die tip in the transport direction of the web.
  • a polymer membrane characterized in that only a tip is placed in contact with the web, and a member for supporting the web via the web is not disposed at a position opposite to the tip of the slit die.
  • Two of the slit dies are disposed via the web to be conveyed, and the two slit dies are disposed such that only the upstream die tip portion contacts the web, It is preferable that the upstream die tip portions of the two slit dies be separated by 1.0 mm or more in the axial direction with the transport direction of the web as a coordinate axis.
  • an angle a formed by the side of the coating liquid being discharged and applied to the web be 90 ° ⁇ a ⁇ 150 ° between the discharge direction of the slit die and the transport direction of the web.
  • the means for bringing the coating into contact with the non-solvent comprises means for spraying the non-solvent, means for applying the non-solvent, means for immersing the coating in the non-solvent, and contacting the vaporized non-solvent with the coating It is preferable that it is a combination of one or more of the means for causing.
  • the polymer film formation method of the present invention for solving the above-mentioned subject has the following composition.
  • the slit die is installed such that only the upstream die tip is in contact with the web, of the slit die tips including the upstream die tip and the downstream die tip in the transport direction of the web.
  • Two of the slit dies are installed via the web, and the two slit dies each contact only the upstream die tip with the web, and the upstream of the two slit dies
  • the side die tips are separated by 1.0 mm or more in the axial direction with the transport direction of the web as a coordinate axis, and the coating solution is applied to both surfaces of the web by the two slit dies to form the coating film It is preferable to do.
  • an angle a between the discharge direction of the slit die and the transport direction of the web and the side on which the coating liquid is discharged and applied to the web is 90 ° ⁇ a ⁇ 150 °.
  • the manufacturing method of the separator of this invention for solving the said subject has the following structures. That is, (12) A method for producing a separator, comprising forming a polymer film on a web by the method for forming a polymer film according to the present invention.
  • the present invention for the polymer film formed on the web, it is possible to select the single-sided, double-sided formation of the web, and to form the both-sides different composition / different thickness with uniform coating without coating defects such as streaks and unevenness. It becomes.
  • this invention is applied to a separator for lithium ion secondary batteries, a separator having a polymer film suitable for each of the positive electrode and the negative electrode can be obtained.
  • FIG. 1 is a schematic view showing an embodiment of a polymer film forming apparatus at the time of single-sided coating.
  • FIG. 2 is a schematic view of a coating unit at the time of single-sided coating.
  • FIG. 3 is a view showing a conventional slit die coating method without using a backup roll.
  • FIG. 4 is a view showing a conventional slit die coating method using a backup roll.
  • FIG. 5a shows the slit die tilt angle a with respect to the web in the case of single-sided coating.
  • FIG. 5 b is a view showing the slit die tilt angle a with respect to the web in the case of double-sided coating.
  • FIG. 6 is a schematic view showing one embodiment of a polymer film forming apparatus at the time of double-sided coating.
  • FIG. 7 is a schematic view of a coating unit at the time of double-sided coating.
  • FIG. 8 is a diagram showing an aspect of the positional relationship between two slit dies.
  • FIG. 9 is a view showing a coating portion of Comparative Example 1.
  • FIG. 10 is a view showing an aspect of the positional relationship between two slit dies.
  • FIG. 11 is a view showing a coating portion of Comparative Example 2.
  • a polymer film forming apparatus includes a slit die having a slit formed therein, and a surface of the web for applying a coating solution containing a polymer solution to the web conveyed downward. And a means for bringing a coating film formed of a coating liquid applied on the substrate into contact with a non-solvent, the slit die including a slit die tip including an upstream die tip and a downstream die tip in the web transport direction.
  • the upstream side die tip is installed in contact with the web, and a member for supporting the web via the web is not disposed at the position opposite to the slit die tip.
  • a polymer film forming method is a method of applying a coating liquid to a web using a slit die having a slit formed therein to form a polymer film, Applying a coating solution to the surface of the web to form a coating; Contacting the coating with a non-solvent to solidify the coating;
  • the slit die is installed such that only the upstream die tip is in contact with the web, of the slit die tips including the upstream die tip and the downstream die tip in the transport direction of the web.
  • a member for supporting the web is not disposed at a position opposite to the tip of the slit die through the web.
  • a method of manufacturing a separator according to an embodiment of the present invention is characterized in that a polymer film is formed on a web by a polymer film forming method.
  • the web transport direction in the process of applying the coating liquid is downward. This is because non-solvent splashing downward can not be avoided regardless of whether the non-solvent contact means is spraying, slit die coating, or immersion in a non-solvent storage tank, and if the transport direction is upward, it is not solidified The non-solvent partially adheres to the coated layer of the above-mentioned to cause unevenness of the polymer film.
  • the “downward direction” refers to the direction in which the web is transported downward with respect to the horizontal direction, and includes not only vertically downward but also diagonally downward.
  • the direction in which the web is conveyed upward with reference to the horizontal direction is referred to as “upward”, and includes not only vertically upward but also diagonally upward.
  • the web conveyance direction side is referred to as “downstream side”
  • the web conveyance direction opposite side is referred to as "upstream side”.
  • the facing position of the tip of the slit die refers to the position of the point of intersection of an imaginary line parallel to the slit and passing through the center of the slit and a surface of the web surface which is not coated by the slit die.
  • FIG. 1 is a schematic view showing a slit die 2 of a coating portion of a polymer film forming apparatus and the periphery thereof in the case of applying a coating liquid on one side of a web 1 according to an embodiment of the present invention.
  • FIG. 2 is a schematic view of a coating portion in the case of applying a coating liquid to one side of the web 1.
  • the back side of the coated surface of the web 1 is not supported by a member supporting the web such as a backup roll at a position facing the coating liquid discharge port 9 in the coating section with respect to the web 1 conveyed downward.
  • a member supporting the web such as a backup roll at a position facing the coating liquid discharge port 9 in the coating section with respect to the web 1 conveyed downward.
  • the slit die tip 8 including the upstream die tip 8a and the downstream die tip 8b in the web conveying direction 17 with respect to the slit 7 of the slit die 2 only the upstream die tip 8a is a web
  • the coating solution 10 is applied to form a coating film 10 on the web 1.
  • a backup roll When applying to a web with a slit die, a backup roll is placed on the back side of the coated surface to support the web in order to ensure uniform clearance, but the web is a non-woven fabric or a microporous polyolefin membrane A part or all of the coating solution containing the polymer solution may penetrate the web, contaminate the backup roll, and may inhibit the transport of the web.
  • the distance to the tip of the slit die can be easily stabilized, but on the other hand, the rotation axis of the roll and the processing accuracy are easily affected. When there is rotational shake, the distance to the tip of the slit die changes with the rotation, so that uneven coating unevenness occurs.
  • the coating liquid permeates the web, and the coating liquid adheres to the backup roll and solidifies, causing uneven thickness, coating streaks, and scratches on the slit die or roll. It may cause web breakage.
  • FIG. 3 there is a slit die coating method as shown in FIG. 3 which does not use a backup roll as a member for supporting the web.
  • the web 1 is supported and guided by a pair of guide rolls 11 arranged at regular intervals upstream and downstream in the web transport direction 17 of the slit die 2.
  • the slit die 2 disposed between the guide rolls 11 applies a coating solution by discharging a necessary amount of coating liquid to the web.
  • the slit die is pressed against the web continuously conveyed between the pair of guide rolls 11, and a force 22 that the bent web tries to return and a force 21 that the coating liquid discharged from the slit die presses the web
  • the distance between the web and the tip of the slit die can be secured and applied.
  • the balance between the force for pressing the web and the force for discharging the coating liquid is important. If the force to press the slit die against the web is weak, the slack of the web can not be canceled and coating unevenness occurs. When the force of the die pressing the web is strong, the coating liquid discharge port of the slit die is closed, the coating liquid can not be stably discharged, and streaks and unevenness occur. In addition, when applying to a highly elastic web, if the pressing force of the die against the web is too strong, the web is deformed, which causes a change in dimensions and a roll of a roll after application. In addition, when the coated coating liquid passes through the web, it is natural for double-sided coating before and after the coating is solidified, and non-coated for single-sided coating after coating. It is not preferable to dispose a backup roll 20 or the like as shown in FIG.
  • the web sag is eliminated by only the upstream die tip of the slit die coming into contact with the web, and the clearance between the discharge port of the coating liquid and the web is kept uniform. And stable coating is possible.
  • the slit die 2 is divided into an upstream side die 3 and a downstream side die 4, and as shown in FIG. 2, a liquid reservoir portion of a coating liquid called a manifold 5 and a slit inside the slit die 2. 7 are formed.
  • the manifold 5 is configured such that its cross section is a curved line and a straight line, and may be substantially circular or semicircular as shown in FIG.
  • the manifold 5 has a cross-sectional shape in the width direction of the slit die 2.
  • the effective extension length is generally equal to or slightly longer than the coating width.
  • the slit 7 is a flow path of the coating liquid 6 from the manifold 5 to the web 1. Similar to the manifold 5, it has the cross-sectional shape in the width direction of the slit die 2.
  • the coating liquid discharge port 9 positioned on the side of the web 1 is adjusted to have a width substantially the same as the coating width using a spacer (not shown). In addition, the slit gap can be adjusted by the thickness of the spacer.
  • the coating liquid 6 extruded from the manifold 5 of the slit die 2 passes through the slit and is discharged from the coating liquid discharge port 9 at the tip of the slit die to form a coating film on the web.
  • an imaginary line parallel to the slit 7 and passing through the center of the slit 7 can be taken as the discharge direction 19.
  • the angle (also referred to as “slit die inclination angle to the web”) a between the discharge direction 19 of the slit die 2 and the transport direction of the web 1 that the coating liquid is discharged and applied to the web 1 is 90 °. It is preferable that ⁇ a ⁇ 150 °. It is preferable to incline the slit die so that the inclination angle a18 of the slit die is 90 ° ⁇ a ⁇ 150 °. More preferably, 110 ° ⁇ a ⁇ 150 °.
  • the clearance between the discharge port of the coating liquid and the web can not be secured, and if it exceeds 150 °, stable retention of the liquid pool becomes difficult.
  • As a means for maintaining the clearance between the coating solution discharge port and the web it is possible to make the upstream die tip of the slit die tip protrude with respect to the downstream die tip and to contact only the upstream die tip
  • the web 1 is conveyed downward by a backup roll or the like at a position facing the coating liquid discharge port 9 in the coating section.
  • the two slit dies 2 can be arranged without supporting the back surface side of the coated surface.
  • One slit die 2 is in contact with the web 1 only on the upstream side die tip 8 a with reference to the slit 7, and can be a first coating portion to which the coating liquid 6 is applied.
  • only the upstream side die tip 8a of the slit die 2 is in contact with the web 1 in order to coat the web surface which is not coated in the first coating unit downstream of the first coating unit.
  • the other slit die 2 may be disposed, and the coating liquid 6 may be applied onto the web 1 to form a second coating portion for forming the coating film 10.
  • Two slit dies are installed via the web, and the two slit dies are arranged such that only the upstream die tip is in contact with the web, and the upstream die tips of the two slit dies It is preferable that they are separated by 1.0 mm or more in the axial direction with the conveyance direction of the web as a coordinate axis, and a coating liquid is applied to both sides of the web by these slit dies to form a coating film.
  • the shapes of the two slit dies may be the same.
  • the two slit dies are installed via the web. By doing so, each surface can be coated with a different composition and thickness.
  • the two slit dies are arranged such that only the upstream die tip of the die is in contact with the web, and the upstream die tips of the two slit dies are axially aligned with the web transport direction as the coordinate axis. It is preferable that they are separated by at least 0. 0 mm. This is because the upstream end of the slit die is brought into contact in order to eliminate web slack and flaps, so the contact point between the upstream die end of the two slit dies and the web is at the same position via the web. When installed, the web is caught by the slit die upstream die tip, and there is the possibility that the web can not be stably transported, the possibility of web breakage, and the possibility of web elongation.
  • the distance between the two slit dies is between the passage of the coating liquid applied to one side (A side) of the web by the slit die installed on the upstream side in the transport direction of the web, through the web, It is preferable to install a slit die on the downstream side so that the coating liquid is also applied to the opposite surface (surface B). If a slit die on the downstream side is installed at a position where the coating liquid is applied to the B side after the coating liquid applied to the A side passes through the web, the slit installed on the downstream side At the contact portion of the die with the web, the coating liquid transmitted from the A surface may be accumulated, which may affect the coating on the B surface.
  • the upper limit of the distance between the two slit dies changes depending on the transport speed of the web, the permeation time of the coating liquid to the web, and the like. For example, if the web transport speed is 100 m / min and the permeation time of the coating liquid to the web is 150 msec, the upper limit of the distance between the two slit dies is 250 mm.
  • the time for the coating solution to permeate through the web is longer as the thickness of the web is larger and the porosity of the web is lower.
  • the time required for the coating liquid applied to the side A to pass through the web changes depending on the web type, and the higher the web conveyance speed, the larger the upper limit of the distance between the two slit dies.
  • a roll may be disposed between the two slits as shown in FIG.
  • means for contacting with a non-solvent to solidify the coating liquid applied to the surface of the web will be described.
  • a means for bringing the coating into contact with the non-solvent there may be mentioned means for spraying the non-solvent, means for applying the non-solvent, means for immersing the coating in the non-solvent, and means for contacting the vaporized non-solvent with the coating.
  • a spray nozzle can be used, and any of a fan type, an empty cone type, a full cone type, etc. may be used. If the non-solvent is water, an ultrasonic mist generator can also be used.
  • a slit die can be used as a means to apply a nonsolvent.
  • a tank storing a nonsolvent for immersing in the web can be used, which is most preferable in order to uniformly solidify the polymer film.
  • the web 1 is formed by the guide roll 11 disposed on the upstream side in the web transport direction 17 of the slit die 2 and the submerged guide roll 12 disposed on the downstream side.
  • the web 1 may be immersed in a nonsolvent tank 14 in which the nonsolvent 13 is stored while being supported and guided.
  • the non-solvent may contain a good solvent and a poor solvent in a concentration range in which the coating can be solidified.
  • the ratio of the non-solvent to the good solvent and the poor solvent affects the time for which the coating film is solidified and the pore shape of the polymer film, so it is preferable to control the solvent concentration.
  • the resin component coagulates in a three-dimensional network to form a polymer film.
  • the contact time with a non-solvent is preferably 3 seconds or more. Less than 3 seconds may not fully coagulate the resin component.
  • the upper limit is not limited.
  • the web on which the polymer film is formed is used for a lithium ion secondary battery separator.
  • a nonwoven fabric or a microporous polyolefin membrane is used as the web.
  • a microporous polyolefin membrane is preferred.
  • the polyolefin forming the microporous polyolefin membrane may be a copolymer of ethylene or propylene homopolymer, an olefin-based copolymer such as ethylene, propylene, butene, hexene, pentene, methyl pentene, octene, vinyl acetate, methyl methacrylate or styrene. Polymers and mixtures thereof are exemplified. Polyethylene, polypropylene, or a copolymer of polyethylene and polypropylene is preferable because the shutdown temperature can be controlled to about 120 ° C. to 150 ° C.
  • polyethylene high density polyethylene, medium density polyethylene, ultra high molecular weight polyethylene (UHMwPE), branched low density polyethylene, linear low density polyethylene, and mixtures thereof can be used.
  • high-density polyethylene, ultra-high-molecular-weight polyethylene and mixtures thereof are preferred from the viewpoint of pore structure control of the microporous membrane and the thermal properties and strength of the membrane.
  • Polyolefins are, for example, amorphous heat-resistant resins, antioxidants, heat stabilizers, antistatic agents, ultraviolet absorbers, antiblocking agents, fillers, and crystal nucleating agents as long as the effects of the present invention are not impaired. And various additives such as a crystallization retarder.
  • the polyethylene microporous membrane may be a single layer membrane, or may be a layer configuration comprising two or more layers having different molecular weights or average pore sizes.
  • a method of producing a multilayer film comprising two or more layers for example, each of the polyethylenes constituting the a layer and the b layer is melt-kneaded with a forming solvent, and the obtained melt mixture is supplied from one extruder to one die.
  • the gel sheet which comprises each component is integrated, and the method of co-extrusion, and the method of superposing and heat-fusing the gel sheet which comprises each layer can also produce.
  • the co-extrusion method is more preferable because it is easy to obtain high interlayer adhesion strength and easily form a communicating hole between the layers, so it is easy to maintain high permeability and excellent in productivity.
  • the molecular weight and molecular weight distribution of at least one outermost layer polyethylene resin satisfy the above.
  • the polymer film in the present invention is to impart or improve at least one function such as heat resistance, adhesion to an electrode material, and electrolyte solution permeability.
  • Inorganic particles may be added to the coating solution containing the polymer solution used in the embodiment of the present invention.
  • inorganic particles calcium carbonate, calcium phosphate, amorphous silica, crystalline glass filler, kaolin, talc, titania, alumina, silica-alumina composite oxide particles, barium sulfate, calcium fluoride, lithium fluoride, zeolite, Molybdenum sulfide, mica, boehmite, etc. may be mentioned.
  • titanium dioxide, alumina and boehmite are preferable in view of crystal growth property, cost and availability, and alumina is more preferable.
  • the polymer solution refers to a solution in which a polymer such as a fluorine resin, polyamide imide, or aramid resin is dissolved in a solvent.
  • the solvent is not particularly limited as long as it can dissolve the polymer, and includes N-methyl-2-pyrrolidone, dimethylformamide, dimethylacetamide, ⁇ -butyl lactone, acetone and the like.
  • the polymer used in the embodiment of the present invention is not particularly limited as long as it improves electrode adhesion, heat resistance and electrolyte permeability, but from the viewpoint of heat resistance and electrode adhesion, it is a fluorine-based resin Among them, one or more selected from the group consisting of vinylidene fluoride homopolymer, vinylidene fluoride / fluorinated olefin copolymer, vinyl fluoride homopolymer, and vinyl fluoride / fluorinated olefin copolymer It is preferred to use Particularly preferred are polyvinylidene fluoride resin and polyvinylidene fluoride-hexafluoropropylene copolymer. These polymers have electrode adhesiveness, high affinity with non-aqueous electrolytes, and high chemical and physical stability with respect to non-aqueous electrolytes. Sufficiently maintain the affinity of
  • the molecular weight of the polyvinylidene fluoride resin is an important factor in controlling the degree of crystallinity.
  • the lower limit of the molecular weight is preferably 0.8 ⁇ 10 6 in weight average molecular weight (Mw), and the upper limit is preferably 2.0 ⁇ 10 6 . Within this range, the crystallinity of the polyvinylidene fluoride resin can be easily made to fall within the above-mentioned preferable range.
  • Commercially available resins can be used as the polyvinylidene fluoride resin. For example, KF polymer W # 7300, KF polymer W # 9300 (made by Kureha Co., Ltd.), etc. are mentioned.
  • the coating liquid used in the embodiment of the present invention may contain a monomer or oligomer having a weight average molecular weight of 5,000 or less.
  • examples of the monomer or oligomer having a weight average molecular weight of 5000 or less include vinylidene fluoride monomer, hexafluoropropylene monomer, vinylidene fluoride oligomer, hexafluoropropylene oligomer and the like.
  • a monomer or oligomer having a weight average molecular weight of 5000 or less is contained in the production of the fluorine-based resin, and it is difficult to completely remove it. According to the present invention, when it contains these, it is suitable for application of a coating liquid.
  • the battery separator manufactured by the apparatus and manufacturing method of the present invention is a secondary battery such as a nickel-hydrogen battery, a nickel-cadmium battery, a nickel-zinc battery, a silver-zinc battery, a lithium ion secondary battery, a lithium polymer secondary battery, etc.
  • a secondary battery such as a nickel-hydrogen battery, a nickel-cadmium battery, a nickel-zinc battery, a silver-zinc battery, a lithium ion secondary battery, a lithium polymer secondary battery, etc.
  • battery separators such as a battery
  • it is used suitably as a separator of a lithium ion secondary battery especially.
  • a fluorine-based resin, alumina particles (average particle diameter 1.0 ⁇ m), and N-methyl-2-pyrrolidone are blended in a weight ratio of 4: 9: 87 respectively, and after completely dissolving the resin component, a bead type dispersing machine Were dispersed. Subsequently, it filtered with the filter of 7 micrometers of filtration limits, and prepared the coating liquid (a).
  • PVdF / HFP 99/1 (molar ratio), weight average molecular weight is 1,000,000) and N-methyl-2-pyrrolidone as a fluorine-based resin in a weight of 5:95 respectively
  • the resin component was completely dissolved, and then filtered with a filter with a filtration limit of 5 ⁇ m to prepare a coating liquid (b).
  • Thickness measurement Evaluation of the degree of thickness variation of the thickness of the polymer film formed 30 points in total of 30 points in 10 m in the width direction 3 points in the width direction The The thickness was measured using LITEMATIC (VL-50-B 0.01N spherical probe) manufactured by Mitutoyo Corporation. : 0: 0% or more and less than 10% ⁇ : 10% or more and less than 15% ⁇ : 15% or more and less than 20% ⁇ : 20% or more.
  • Example 1 As shown in FIG. 1, with respect to the web being conveyed in the substantially vertical downward direction, in the coating section, a backup roll for supporting the web is not used at a position facing the slit die.
  • an apparatus was used in which the slit die was installed such that only the upstream die tip in the web transport direction was in contact.
  • a coating solution (a) is applied to one side of the web with a thickness of 10 ⁇ m, and a non-solvent tank filled with ion exchange water is installed on the downstream side of the slit die transport direction to solidify the coating.
  • the coated film was immersed and solidified along with the web, and the polymer film was formed through a water-washing step of immersion in a water-washing tank filled with ion-exchanged water and a hot-air drying step of 50 ° C.
  • a polyolefin microporous film with a thickness of 10 ⁇ m was used, and applied at a conveyance speed of 10 m / min.
  • the thickness of the obtained polymer film was 1.5 ⁇ m.
  • coating was performed at a slit die inclination angle a with respect to the web at a level of 110 °, 135 °, and 150 °. As a result, as shown in Table 1, stable coating without coating defects such as streaks and unevenness was able to be performed.
  • Comparative Example 1 Regarding the application part, it is carried out except that the slit die tip does not contact the web as shown in FIG. 9 and the slit die inclination angle a with respect to the web is changed to 90 °, 110 °, 135 °, 150 °.
  • the application was performed under the same conditions as in Example 1. As a result, as shown in Table 1, coating defects such as streaks and unevenness frequently occurred.
  • Example 2 As shown in FIG. 6, two slit dies are installed via the web, the slit die on the upstream side in the transport direction 17 is a slit die A, and the slit die on the downstream side is a slit die B.
  • a backup roll for supporting the web is not used at a position facing the slit die tip, and the web conveyance direction of the slit die tip is The coating liquid (a) is coated on one side with a thickness of 10 ⁇ m using an apparatus provided with a slit die A so that only the tip side of the upstream die contacts the web, and the downstream in the transport direction of the slit die A
  • a backup roll is not used like the slit die A, and only the upstream die tip in the web transport direction of the slit die tip is the web
  • the coating liquid (a) is applied on one side with
  • a polyolefin microporous film with a thickness of 10 ⁇ m was used as a web to be applied, and applied at a transfer speed of 10 m / min.
  • the thickness of the obtained polymer film was 1.5 ⁇ m on both sides.
  • the distance between the slit die A and the slit die B was 15 mm (see FIG. 10).
  • coating was performed at the inclination angles a of the slit dies A and B with respect to the web of 110 °, 135 °, and 150 °. As a result, as shown in Table 2, stable coating without coating defects such as streaks and unevenness was able to be performed even in double-sided coating.
  • Comparative Example 2 With respect to the coating unit, as shown in FIG. 11, the discharge openings of the two slit dies are disposed to face each other via the web, and the two slit die tips are not in contact with the web; Coating was performed under the same conditions as in Example 2 except that the angles formed with the slit die were 90 °, 110 °, 135 °, and 150 °. As a result, as shown in Table 2, coating defects such as streaks and unevenness occurred frequently.
  • Table 3 stable coating without coating defects such as streaks and unevenness was able to be performed even if the thickness of both sides is different.
  • Example 4 The same conditions as in Example 3 are used except that the coating liquid (a) is used as the coating liquid for slit die A and the coating liquid (b) is used as the coating liquid for slit die B in Example 3. Coating was performed to form a polymer film.
  • Table 4 stable coating without coating defects such as streaks and unevenness was able to be performed even with a coating liquid having different surface types.
  • the present invention makes it possible to select single-sided, double-sided formation of a web, and to form different compositions / different thicknesses on both sides of a polymer film to be formed on a web, by uniform coating with no coating defects such as streaks and unevenness.
  • this invention is applied to a separator for lithium ion secondary batteries, a separator having a polymer film suitable for each of the positive electrode and the negative electrode can be obtained.

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  • Application Of Or Painting With Fluid Materials (AREA)
  • Coating Apparatus (AREA)
  • Cell Separators (AREA)

Abstract

L'invention concerne un dispositif de formation de film polymère, comportant : une filière à fente (2), dans laquelle une fente (7) est formée en vue d'appliquer un liquide de revêtement contenant une solution polymère à une bande (1) qui est transportée dans la direction vers le bas ; et un moyen destiné à amener un film constitué du liquide de revêtement appliqué sur la surface de la bande (1) à entrer en contact avec un non-solvant, la filière à fente (2) étant logée de sorte que, parmi des parties de pointe de filière à fente (8) comprenant une partie de pointe de filière côté amont (8a) et une partie de pointe de filière côté aval (8b) dans la direction de transport de la bande (1), seule la partie de pointe de filière côté amont (3) soit en contact avec la bande (1), et qu'un élément destiné à maintenir la bande (1) entre ces dernières ne soit pas disposé à une position faisant face aux parties de pointe de filière à fente (8).
PCT/JP2018/031992 2017-08-30 2018-08-29 Dispositif de formation de film polymère, procédé de formation de film polymère et procédé de production de séparateur WO2019044918A1 (fr)

Priority Applications (3)

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KR1020197035760A KR20190140070A (ko) 2017-08-30 2018-08-29 고분자막 형성 장치, 고분자막 형성 방법 및 세퍼레이터의 제조 방법
CN201880041251.0A CN110831705A (zh) 2017-08-30 2018-08-29 高分子膜形成装置、高分子膜形成方法及隔膜的制造方法
JP2018550848A JPWO2019044918A1 (ja) 2017-08-30 2018-08-29 高分子膜形成装置、高分子膜形成方法およびセパレータの製造方法

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2022131271A1 (fr) * 2020-12-18 2022-06-23 富士フイルム株式会社 Procédé de fabrication d'un corps stratifié
WO2022131272A1 (fr) * 2020-12-18 2022-06-23 富士フイルム株式会社 Procédé de production de corps multicouche

Citations (4)

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Publication number Priority date Publication date Assignee Title
JPH09141174A (ja) * 1995-11-24 1997-06-03 Konica Corp 塗布装置及び塗布方法
JPH11221512A (ja) * 1997-11-18 1999-08-17 Matsushita Electric Ind Co Ltd 塗布装置、及び塗布方法
JP2003117466A (ja) * 2001-10-16 2003-04-22 Toray Ind Inc 塗布方法および装置
JP2017135111A (ja) * 2015-03-24 2017-08-03 帝人株式会社 非水系二次電池用セパレータ及び非水系二次電池

Family Cites Families (2)

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Publication number Priority date Publication date Assignee Title
JP2000262953A (ja) * 1999-03-18 2000-09-26 Fuji Photo Film Co Ltd 塗布装置
DE10337768A1 (de) * 2003-08-14 2005-03-17 Nordson Corporation, Westlake Düsen- und Filteranordnung sowie System zum Auftragen von Fluid mit festen Partikeln auf ein Substrat

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH09141174A (ja) * 1995-11-24 1997-06-03 Konica Corp 塗布装置及び塗布方法
JPH11221512A (ja) * 1997-11-18 1999-08-17 Matsushita Electric Ind Co Ltd 塗布装置、及び塗布方法
JP2003117466A (ja) * 2001-10-16 2003-04-22 Toray Ind Inc 塗布方法および装置
JP2017135111A (ja) * 2015-03-24 2017-08-03 帝人株式会社 非水系二次電池用セパレータ及び非水系二次電池

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2022131271A1 (fr) * 2020-12-18 2022-06-23 富士フイルム株式会社 Procédé de fabrication d'un corps stratifié
WO2022131272A1 (fr) * 2020-12-18 2022-06-23 富士フイルム株式会社 Procédé de production de corps multicouche
CN116583359A (zh) * 2020-12-18 2023-08-11 富士胶片株式会社 层叠体的制造方法

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CN110831705A (zh) 2020-02-21
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JPWO2019044918A1 (ja) 2020-08-13

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