WO2022244774A1 - フッ素樹脂からの金属異物の除去方法及び金属異物が低減されたフッ素樹脂の製造方法 - Google Patents
フッ素樹脂からの金属異物の除去方法及び金属異物が低減されたフッ素樹脂の製造方法 Download PDFInfo
- Publication number
- WO2022244774A1 WO2022244774A1 PCT/JP2022/020540 JP2022020540W WO2022244774A1 WO 2022244774 A1 WO2022244774 A1 WO 2022244774A1 JP 2022020540 W JP2022020540 W JP 2022020540W WO 2022244774 A1 WO2022244774 A1 WO 2022244774A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- fluororesin
- foreign matter
- fluorine resin
- screen
- metal
- Prior art date
Links
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 49
- 239000002184 metal Substances 0.000 title claims abstract description 49
- 238000000034 method Methods 0.000 title claims abstract description 31
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 18
- 229920005989 resin Polymers 0.000 title abstract description 18
- 239000011347 resin Substances 0.000 title abstract description 18
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 title abstract description 9
- 239000011737 fluorine Substances 0.000 title abstract description 9
- 229910052731 fluorine Inorganic materials 0.000 title abstract description 9
- 239000000356 contaminant Substances 0.000 title abstract 6
- 230000005291 magnetic effect Effects 0.000 claims abstract description 30
- 230000005484 gravity Effects 0.000 claims abstract description 13
- 239000000843 powder Substances 0.000 claims description 24
- 239000000696 magnetic material Substances 0.000 claims description 7
- 239000008187 granular material Substances 0.000 claims description 5
- 239000008188 pellet Substances 0.000 claims description 5
- 150000002739 metals Chemical class 0.000 abstract description 4
- 229910001220 stainless steel Inorganic materials 0.000 description 8
- 239000010935 stainless steel Substances 0.000 description 8
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 6
- 238000004140 cleaning Methods 0.000 description 5
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 5
- 239000004810 polytetrafluoroethylene Substances 0.000 description 5
- 238000006116 polymerization reaction Methods 0.000 description 4
- KHXKESCWFMPTFT-UHFFFAOYSA-N 1,1,1,2,2,3,3-heptafluoro-3-(1,2,2-trifluoroethenoxy)propane Chemical compound FC(F)=C(F)OC(F)(F)C(F)(F)C(F)(F)F KHXKESCWFMPTFT-UHFFFAOYSA-N 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 3
- 239000003814 drug Substances 0.000 description 3
- BFKJFAAPBSQJPD-UHFFFAOYSA-N tetrafluoroethene Chemical group FC(F)=C(F)F BFKJFAAPBSQJPD-UHFFFAOYSA-N 0.000 description 3
- 238000005260 corrosion Methods 0.000 description 2
- 230000007797 corrosion Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 229920000642 polymer Polymers 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 229910001111 Fine metal Inorganic materials 0.000 description 1
- BGPVFRJUHWVFKM-UHFFFAOYSA-N N1=C2C=CC=CC2=[N+]([O-])C1(CC1)CCC21N=C1C=CC=CC1=[N+]2[O-] Chemical compound N1=C2C=CC=CC2=[N+]([O-])C1(CC1)CCC21N=C1C=CC=CC1=[N+]2[O-] BGPVFRJUHWVFKM-UHFFFAOYSA-N 0.000 description 1
- 229910052779 Neodymium Inorganic materials 0.000 description 1
- 239000002033 PVDF binder Substances 0.000 description 1
- 229920006361 Polyflon Polymers 0.000 description 1
- -1 alkane hydrochloride Chemical class 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- QHSJIZLJUFMIFP-UHFFFAOYSA-N ethene;1,1,2,2-tetrafluoroethene Chemical compound C=C.FC(F)=C(F)F QHSJIZLJUFMIFP-UHFFFAOYSA-N 0.000 description 1
- 229920002313 fluoropolymer Polymers 0.000 description 1
- 239000004811 fluoropolymer Substances 0.000 description 1
- 230000000977 initiatory effect Effects 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 230000005389 magnetism Effects 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- QEFYFXOXNSNQGX-UHFFFAOYSA-N neodymium atom Chemical compound [Nd] QEFYFXOXNSNQGX-UHFFFAOYSA-N 0.000 description 1
- BCCOBQSFUDVTJQ-UHFFFAOYSA-N octafluorocyclobutane Chemical compound FC1(F)C(F)(F)C(F)(F)C1(F)F BCCOBQSFUDVTJQ-UHFFFAOYSA-N 0.000 description 1
- 235000019407 octafluorocyclobutane Nutrition 0.000 description 1
- 229920002493 poly(chlorotrifluoroethylene) Polymers 0.000 description 1
- 239000005023 polychlorotrifluoroethylene (PCTFE) polymer Substances 0.000 description 1
- 239000003505 polymerization initiator Substances 0.000 description 1
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 1
- YPVDWEHVCUBACK-UHFFFAOYSA-N propoxycarbonyloxy propyl carbonate Chemical compound CCCOC(=O)OOC(=O)OCCC YPVDWEHVCUBACK-UHFFFAOYSA-N 0.000 description 1
- 229910052761 rare earth metal Inorganic materials 0.000 description 1
- 150000002910 rare earth metals Chemical class 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03C—MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03C1/00—Magnetic separation
- B03C1/32—Magnetic separation acting on the medium containing the substance being separated, e.g. magneto-gravimetric-, magnetohydrostatic-, or magnetohydrodynamic separation
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
- B29B17/00—Recovery of plastics or other constituents of waste material containing plastics
- B29B17/02—Separating plastics from other materials
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03C—MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03C1/00—Magnetic separation
- B03C1/02—Magnetic separation acting directly on the substance being separated
- B03C1/30—Combinations with other devices, not otherwise provided for
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03C—MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03C1/00—Magnetic separation
- B03C1/02—Magnetic separation acting directly on the substance being separated
- B03C1/025—High gradient magnetic separators
- B03C1/031—Component parts; Auxiliary operations
- B03C1/033—Component parts; Auxiliary operations characterised by the magnetic circuit
- B03C1/0335—Component parts; Auxiliary operations characterised by the magnetic circuit using coils
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03C—MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03C1/00—Magnetic separation
- B03C1/02—Magnetic separation acting directly on the substance being separated
- B03C1/26—Magnetic separation acting directly on the substance being separated with free falling material
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F6/00—Post-polymerisation treatments
- C08F6/02—Neutralisation of the polymerisation mass, e.g. killing the catalyst also removal of catalyst residues
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03C—MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03C2201/00—Details of magnetic or electrostatic separation
- B03C2201/20—Magnetic separation whereby the particles to be separated are in solid form
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03C—MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03C2201/00—Details of magnetic or electrostatic separation
- B03C2201/22—Details of magnetic or electrostatic separation characterised by the magnetical field, special shape or generation
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03C—MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03C2201/00—Details of magnetic or electrostatic separation
- B03C2201/28—Parts being easily removable for cleaning purposes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
- B29B17/00—Recovery of plastics or other constituents of waste material containing plastics
- B29B17/02—Separating plastics from other materials
- B29B2017/0213—Specific separating techniques
- B29B2017/0217—Mechanical separating techniques; devices therefor
- B29B2017/0224—Screens, sieves
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
- B29B17/00—Recovery of plastics or other constituents of waste material containing plastics
- B29B17/02—Separating plastics from other materials
- B29B2017/0213—Specific separating techniques
- B29B2017/0268—Separation of metals
- B29B2017/0272—Magnetic separation
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2027/00—Use of polyvinylhalogenides or derivatives thereof as moulding material
- B29K2027/12—Use of polyvinylhalogenides or derivatives thereof as moulding material containing fluorine
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2027/00—Use of polyvinylhalogenides or derivatives thereof as moulding material
- B29K2027/12—Use of polyvinylhalogenides or derivatives thereof as moulding material containing fluorine
- B29K2027/16—PVDF, i.e. polyvinylidene fluoride
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2027/00—Use of polyvinylhalogenides or derivatives thereof as moulding material
- B29K2027/12—Use of polyvinylhalogenides or derivatives thereof as moulding material containing fluorine
- B29K2027/18—PTFE, i.e. polytetrafluorethene, e.g. ePTFE, i.e. expanded polytetrafluorethene
-
- 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
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/62—Plastics recycling; Rubber recycling
Definitions
- the present disclosure relates to a method for removing metallic foreign matter from fluororesin and a method for producing fluororesin with reduced metallic foreign matter.
- Fluoropolymers are used in a wide variety of applications. Metallic foreign matter may be mixed in due to rubbing or corrosion of manufacturing equipment. Therefore, the removal of metallic foreign matter from fluororesin containing metallic foreign matter is an important issue.
- Patent Literatures 1 and 2 disclose the use of magnets to remove trace amounts of metallic foreign matter in resin.
- Patent Document 3 discloses separating and collecting a fluorine-containing resin powder using a liquid medium consisting of an alkane hydrochloride and an aqueous liquid medium.
- Patent Literature 4 discloses that a solvent is used to remove foreign matter in a fluororesin.
- JP 2005-263985 A JP-A-2005-21761 JP-A-54-071155 WO 2004/009653
- An object of the present disclosure is to provide a method for suitably removing metallic foreign matter in fluororesin and a method for producing fluororesin with reduced metallic foreign matter, which includes a method for removing metallic foreign matter in the fluororesin as one step.
- This disclosure is A method for removing metal foreign matter from a fluororesin, characterized in that the metal is removed by applying a magnetic field with a magnet while dropping the fluororesin by gravity. It is preferable that the above method for removing metal foreign matter includes a screen made of a magnetic material in the flow path through which the fluororesin drops by gravity.
- the magnets are preferably electromagnets.
- the fluororesin is preferably powder, pellets or granules. In the method for removing metal foreign matter from the fluororesin, it is preferable not to vibrate the screen when the fluororesin is passed through the screen.
- the present disclosure also provides a method for producing a fluororesin with reduced metal foreign matter, characterized by having a step of removing metal by applying a magnetic field with an electromagnet while allowing the fluororesin to drop by gravity.
- a screen made of a magnetic material is provided in the flow path through which the fluororesin drops by gravity.
- the magnets are preferably electromagnets.
- the fluororesin is preferably powder, pellets or granules. In the method for producing a fluororesin, it is preferable not to vibrate the screen when the fluororesin is passed through the screen.
- the method for removing metallic foreign matter in the fluororesin of the present disclosure can efficiently remove metallic foreign matter at low cost and with high precision. As a result, it is possible to reduce the amount of resin to be lot-out when checking for metallic foreign matter, and to efficiently provide fluororesin with little metallic foreign matter.
- the present disclosure is a method for removing metals in fluororesin.
- the fluororesin used here is not particularly limited. Specific examples include PTFE resin, PFA resin, FEP resin, ETFE resin, PCTFE resin, PVDF resin, and the like. Among these, PTFE resin is particularly preferred.
- the fluororesin is preferably solid, and can be applied to powders, granules, pellets, and other forms of any shape.
- the metal may exist alone in the form of metal powder or the like, or it may be a combination of the metal and the fluororesin.
- the foreign matter is removed by magnetic force, even if the metal and fluororesin, which are more difficult to remove, are integrated, they can be preferably removed.
- metals mixed as foreign substances include stainless steel, iron, and metals in which other elements are mixed with these.
- the metal in the fluororesin is mainly due to the contamination of metal foreign matter due to rubbing or corrosion of manufacturing equipment, and the occurrence rate is not high. However, if this occurs, it will cause defective products in various applications, so it is preferable to be able to remove it with as high precision as possible.
- the present disclosure is characterized in that the metal is removed by applying a magnetic field with a magnet while allowing the fluororesin to drop by gravity.
- the surrounding fluororesin interferes with the magnetic force, and the metal foreign matter may not be sufficiently removed.
- metal foreign matter placed on the fluororesin may not be sufficiently removed by the magnetic force. Since the fluorine resin is also removed to some extent along with the foreign matter, there is also the problem that a constant rate of loss always occurs during operation.
- the magnets used in this disclosure may be electromagnets or permanent magnets.
- the use of an electromagnet is more preferable in that a stronger magnetic field can be applied.
- By turning off the power supply it is also preferable in that metal foreign matter can be easily removed during cleaning.
- Permanent magnets can be used in the same way, but the use of electromagnets is more preferable from the standpoint of foreign matter removal efficiency, such as low magnetic force, large space between magnets that can be installed, and difficulty in removing foreign matter that has adhered during cleaning.
- the magnetic force applied to the fluororesin is preferably 0.8 tesla or more, more preferably 1.2 tesla or more.
- treatment in such a high magnetic force region is preferable in that fine metal can be removed.
- a screen made of a magnetic material may be set in the space where the fluororesin falls.
- the screen becomes magnetic due to the electromagnet, which plays a role in removing metal foreign matter. It is also preferable to stop the electromagnet during cleaning so that metal foreign matter adhering to the screen can be easily removed.
- the screen may be made of permanent magnets. Since such a screen has magnetism due to permanent magnets, a similar effect can be obtained.
- the shape of the screen is not particularly limited, and examples thereof include a 5 mm screen, honeycomb, and micropitch.
- metal foreign matter removing method will be described in more detail with reference to FIG. 1 below.
- several metal screens may be placed on the path along which the fluororesin falls due to gravity.
- FIG. 1 shows the state in which the screen is set in the electromagnetic separator.
- One or more screens 1 made of a magnetic material are vertically multi-layered by holding rods 3 in the hollow part of a cylinder 2 whose upper and lower ends are open. is held to
- the tube 2 may be arranged at the center of the electromagnet 4 and the vibrator 5 may be attached to the bottom of the tube 2 . Note that the vibrator 5 is an optional requirement and may not be provided.
- the vibrator 5 when powdery fluororesin is used, it is preferable not to use the vibrator 5 . If a vibrator is used, the fluororesin may get into the gaps to form flakes or agglomerates of the resin, or rubbing due to vibration may generate new metal pieces, so it is preferable not to use a vibrator.
- a product outlet and a magnetic foreign matter outlet may be connected to the bottom of the cylinder.
- the product outlet and the magnetic foreign matter outlet can be switched by rotating a damper with a cylinder.
- the fluororesin containing the magnetic foreign matter supplied from the top of the tube 2 into the inside is dropped in the direction indicated by the arrow in FIG. It is magnetically attached to the screen magnetized by the magnet 4 .
- the product from which the magnetic foreign matter has been removed is discharged from the bottom of the cylinder 2 after passing through the screen.
- the magnet is an electromagnet
- the electromagnet can be turned off to demagnetize the screen to remove magnetic foreign matter adhering to the screen.
- the screen 1 can be taken out with a holding bar and cleaned to remove magnetic foreign matter. The cleaned screen can be reinserted into the cylinder.
- FIG. 2 shows an apparatus for removing magnetic foreign matter by bringing a drop-shaped magnet into contact with fluororesin containing magnetic foreign matter.
- the drop-shaped magnet 11 has a semi-arc portion in the lower portion and a triangular portion in the upper portion. The foreign matter is removed by the magnet while falling along the slope of the triangular portion.
- a plurality of the drop-shaped magnets be arranged via a yoke.
- the apparatus of FIG. 2 can also remove magnetic foreign matter.
- the present disclosure is a method for removing metallic foreign matter from a fluororesin as described above, and also a method for producing a fluororesin with reduced metallic foreign matter, which includes a step of removing such metallic foreign matter.
- a fluororesin in which metallic foreign matter is reduced there are various approaches to try to obtain "a fluororesin in which metallic foreign matter is reduced”.
- the present disclosure also provides a novel technique for obtaining "a fluororesin with reduced metallic foreign matter”.
- a method for producing a fluororesin with reduced metallic foreign matter according to the present disclosure includes a step of removing metallic foreign matter from the fluororesin by the method described above.
- the “step of removing metallic foreign matter” here can be as described above.
- the method for producing a fluororesin with reduced metallic foreign matter according to the present disclosure may further include a step for removing metallic foreign matter other than the steps described above.
- the method for removing metallic foreign matter of the present disclosure has a slow processing speed. That is, if a large amount of fluororesin is treated in a short period of time, it becomes difficult to sufficiently remove metallic foreign matter, which is not preferable.
- Examples 1-3 A sample was prepared by adding 500 ppm of stainless steel 316L powder (SUS316L powder, 150 ⁇ mpass, manufactured by Kojundo Chemical Co., Ltd.) to PTFE granulated powder (Polyflon PTFE M-392 manufactured by Daikin Industries, Ltd.). 5 kg of PTFE granulated powder containing stainless steel powder was prepared and used for each test.
- the apparatus used is an electromagnetic separator (CG-180X-1 type) manufactured by Nippon Magnetics Co., Ltd. An electromagnet was used as the magnet.
- the screen is made of a magnetic material.
- a bar magnet of 15000 G is wrapped with a medicine wrapping paper without gaps and fixed with tape. Such bar magnets are fixed by clamps.
- a powder to be measured is passed over the bar magnet.
- the treatment speed is set at 4 kg/hour.
- pouring the powder pour the recovered powder over the bar magnet again.
- Such work causes the metal in the powder to adhere to the magnet.
- a bar magnet is placed on a heat-resistant metal container, the tape fixing the medicine wrapping paper is removed, and the medicine wrapping paper is removed from the bar magnet.
- the metal adhering to the metal falls into the heat-resistant metal container.
- Such a heat-resistant metal container is placed in an electric furnace at 600° C. and taken out after 2 hours.
- Table 1 shows a value calculated as a ratio of the amount of metal thus measured to the amount of stainless steel powder added to the sample as a residual stainless steel ratio.
- Polymerization was initiated by adding 0.028 kg of a 50% methanol solution of di-n-propylperoxydicarbonate [NPP] as a polymerization initiator. Since the pressure decreased as the polymerization progressed, TFE and PPVE were continuously added at a ratio that gave the desired polymer composition.
- NPP di-n-propylperoxydicarbonate
- Examples 4 and 5 A sample was prepared by adding 500 ppm of stainless steel 316L powder (manufactured by Kojundo Chemical Co., Ltd., SUS316L powder, 150 ⁇ m pass) to the PFA powder obtained by the above method. 1 kg of PFA powder containing stainless steel powder was prepared and used for each test.
- the device used is a grating magnet with a housing manufactured by Magnetec Japan Co., Ltd. (neodymium-based rare earth magnet; the magnet is a permanent magnet).
- the removal method of the present disclosure can suitably remove metallic foreign matter from the fluororesin.
Landscapes
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)
Abstract
Description
特許文献3には、塩フッ化アルカン及び水液媒からなる液媒を利用して含フッ素樹脂粉末を分離採取することが開示されている。
特許文献4には、溶媒を利用してフッ素樹脂中の異物除去を行うことが開示されている。
フッ素樹脂を重力によって落下させつつ、磁石によって磁場を付与することによって金属を除去することを特徴とするフッ素樹脂からの金属異物の除去方法である。
上記金属異物の除去方法は、フッ素樹脂を重力によって落下させる流路中に、磁性体からなるスクリーンを備えたものであることが好ましい。
上記磁石は、電磁石であることが好ましい。
上記フッ素樹脂は、粉体、ペレット又は造粒物であることが好ましい。
上記フッ素樹脂からの金属異物の除去方法は、フッ素樹脂をスクリーンに通過させる際にスクリーンに振動を与えないことが好ましい。
上記フッ素樹脂の製造方法は、フッ素樹脂を重力によって落下させる流路中に、磁性体からなるスクリーンを備えたものであることが好ましい。
上記磁石は、電磁石であることが好ましい。
上記フッ素樹脂は、粉体、ペレット又は造粒物であることが好ましい。
上記フッ素樹脂の製造方法は、フッ素樹脂をスクリーンに通過させる際にスクリーンに振動を与えないことが好ましい。
本開示は、フッ素樹脂中の金属を除去する方法である。ここでのフッ素樹脂としては特に限定されない。具体的には、PTFE樹脂、PFA樹脂、FEP樹脂、ETFE樹脂、PCTFE樹脂、PVDF樹脂等を挙げることができる。これらのなかでも、PTFE樹脂が特に好ましい。フッ素樹脂は、固体であることが好ましく、粉体、造粒物、ペレット等の任意の形状のものに対して適用することができる。
例えば、ローラーやコンベア等を使用して水平方向にフッ素樹脂を移動させながら磁力を付与した場合、フッ素樹脂上に金属異物が載置されると、磁力によって十分に除去されない場合がある。異物に付随してフッ素樹脂もある程度除かれてしまうため、稼働していると常に一定の割合でロスが出るという問題もある。
電磁石を利用すると、より強度の強い磁場を付与することができる点で、より好ましいものである。さらに、電源を切断することで、洗浄時に金属異物を容易に除去できる点でも好ましい。永久磁石も同様に使えるが、磁力が低い、設置できる磁石の間隔が大きくなる、清掃時に付着した異物の除去が難しいなど、異物除去効率から見ると電磁石の使用がより好ましい。
本開示の除去方法においては、フッ素樹脂が重力によって落下する経路上にいくつかの金属製スクリーンを設置するものであってもよい。
図2においては、しずく状マグネットを磁性異物を含むフッ素樹脂と接触させることによって、磁性異物を除去する装置を示すものである。
しずく状マグネット11は、図2に示したように下方部に半円弧部を有し、上部に三角部を有する。三角部の斜面に沿って落下しながら、異物が磁石によって除去されることとなる。
さらに、当該しずく状マグネットは、ヨークを介して複数個配列したものであることが好ましい。このような図2の装置によっても、磁性異物を除去することができる。
すなわち、「金属異物が低減されたフッ素樹脂」を得るための試みは、種々の手法が存在する。
本開示においては、「金属異物が低減されたフッ素樹脂」を得るための新規な手法を提供するものでもある。
PTFE造粒品粉末(ダイキン工業製ポリフロンPTFE M-392)中にステンレス316L粉末(高純度化学製、SUS316L粉末 150μmpass)を500ppm加えたものをサンプルとした。
ステンレス粉末を含むPTFE造粒粉末を5kgを用意し、各テストに使用した。
使用した装置は日本マグネティックス株式会社製、電磁分離機(CG-180X-1型)である。磁石としては電磁石を使用した。さらに、当該装置においては、スクリーンが磁性体からなるものである。
なお、表1の結果から振動させないほうが、良好な結果となることが明らかになった。
15000Gの棒磁石に薬包紙を隙間なく巻き付け、テープで固定する。このような棒磁石をクランプによって固定する。当該棒磁石上に測定対象の粉体を流す。処理速度は、4kg/時間を目安とする。粉体を流し終えたら、回収した粉体を再度棒磁石上に流す。このような作業によって、粉体中の金属を磁石に付着させる。
その後、耐熱金属容器の上に棒磁石をのせて、薬包紙を固定しているテープを外し、薬包紙を棒磁石から外す。これによって、金属に付着した金属が、耐熱金属容器内に落下する。
このような耐熱金属容器を600℃の電気炉に投入し2時間後に容器を取り出す。空冷後、容器の重量を測定し、この値から空容器の重量を差し引くことで、金属含有量を測定した。
このようにして測定された金属量をサンプルに加えたステンレス粉末量に対する割合として計算した値をステンレス残存率として表1に示した。
撹拌機を備え、ガラスライニングしたオートクレーブ(容積174L)に純水26.6kgを仕込んだ。オートクレーブ内部を充分にN2に置換した後、真空にし、パーフルオロシクロブタン〔C-318〕を30.4kg、メタノールを0.8kg、パーフルオロ(プロピルビニルエーテル)〔PPVE〕を1.6kg仕込んだ。次いで撹拌しながら、オートクレーブ内を35℃に保ち、テトラフルオロエチレン〔TFE〕を圧入し、内圧を0.58MPaGとした。重合開始剤としてジ-n-プロピルパーオキシジカーボネート〔NPP〕の50%メタノール溶液0.028kgを添加して重合を開始した。重合の進行に伴い圧力が低下するので、目的のポリマー組成となる比率でTFEとPPVEを連続追加した。
上述した方法で得られたPFA粉末中にステンレス316L粉末(高純度化学製、SUS316L粉末 150μmpass)を500ppm加えたものをサンプルとした。
ステンレス粉末を含むPFA粉末を1kg用意し、各テストに使用した。
使用した装置は株式会社マグネテックジャパン製ハウジング付き格子マグネットである(ネオジム系希土類磁石;磁石は永久磁石である)。
2:筒
3:保持棒
4:電磁石
5:バイブレーター
6:製品排出口
7:鉄粉排出口
8:シリンダ
9:ダンパ
11:しずく状マグネット
Claims (10)
- フッ素樹脂を重力によって落下させつつ、磁石によって磁場を付与することによって金属を除去することを特徴とするフッ素樹脂からの金属異物の除去方法。
- フッ素樹脂を重力によって落下させる流路中に、磁性体からなるスクリーンを備えたものである請求項1記載のフッ素樹脂からの金属異物の除去方法。
- 磁石は、電磁石である請求項1又は2記載のフッ素樹脂からの金属異物の除去方法。
- フッ素樹脂は、粉体、ペレット又は造粒物である請求項1、2又は3記載のフッ素樹脂からの金属異物の除去方法。
- フッ素樹脂をスクリーンに通過させる際にスクリーンに振動を与えない請求項1~4のいずれか記載のフッ素樹脂からの金属異物の除去方法。
- フッ素樹脂を重力によって落下させつつ、磁石によって磁場を付与することによって金属を除去する工程を有することを特徴とする金属異物が低減されたフッ素樹脂の製造方法。
- フッ素樹脂を重力によって落下させる流路中に、磁性体からなるスクリーンを備えたものである請求項6記載のフッ素樹脂の製造方法。
- 磁石は、電磁石である請求項6又は7記載のフッ素樹脂の製造方法。
- フッ素樹脂は、粉体、ペレット又は造粒物である請求項6,7又は8記載のフッ素樹脂の製造方法。
- フッ素樹脂をスクリーンに通過させる際にスクリーンに振動を与えない請求項1~4のいずれか記載のフッ素樹脂からの金属異物の除去方法。
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2023522676A JPWO2022244774A1 (ja) | 2021-05-20 | 2022-05-17 | |
EP22804685.0A EP4342916A1 (en) | 2021-05-20 | 2022-05-17 | Method for removing metal contaminants from fluorine resin and method for producing fluorine resin having reduced amount of metal contaminants |
CN202280033892.8A CN117295773A (zh) | 2021-05-20 | 2022-05-17 | 从氟树脂除去金属异物的方法和减少了金属异物的氟树脂的制造方法 |
US18/507,699 US20240075481A1 (en) | 2021-05-20 | 2023-11-13 | Method for removing metallic foreign matter from fluororesin and method for producing fluororesin with reduced metallic foreign matter |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202110549939.3A CN115366293A (zh) | 2021-05-20 | 2021-05-20 | 从氟树脂中去除金属异物的方法和减少了金属异物的氟树脂的制造方法 |
CN202110549939.3 | 2021-05-20 |
Related Child Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US18/507,699 Continuation US20240075481A1 (en) | 2021-05-20 | 2023-11-13 | Method for removing metallic foreign matter from fluororesin and method for producing fluororesin with reduced metallic foreign matter |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2022244774A1 true WO2022244774A1 (ja) | 2022-11-24 |
Family
ID=84058672
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2022/020540 WO2022244774A1 (ja) | 2021-05-20 | 2022-05-17 | フッ素樹脂からの金属異物の除去方法及び金属異物が低減されたフッ素樹脂の製造方法 |
Country Status (6)
Country | Link |
---|---|
US (1) | US20240075481A1 (ja) |
EP (1) | EP4342916A1 (ja) |
JP (1) | JPWO2022244774A1 (ja) |
CN (2) | CN115366293A (ja) |
TW (1) | TW202307103A (ja) |
WO (1) | WO2022244774A1 (ja) |
Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5471155A (en) | 1977-11-18 | 1979-06-07 | Mitsui Fluorochemicals Co Ltd | Method for removing tramp material from fluorineecontaining resin powder |
JPH0474546A (ja) * | 1990-07-17 | 1992-03-09 | Mitsubishi Gas Chem Co Inc | 永久磁石式ロールセパレータ |
JP2003137922A (ja) * | 2001-07-06 | 2003-05-14 | Nippon Shokubai Co Ltd | 吸水性樹脂粉末、その製造方法およびその用途 |
JP2005021761A (ja) | 2003-06-30 | 2005-01-27 | Sumitomo Bakelite Co Ltd | 不純物の除去装置 |
JP2005066952A (ja) * | 2003-08-21 | 2005-03-17 | Daicel Chem Ind Ltd | プラスチック混合物の分別処理システム |
JP2005263985A (ja) | 2004-03-18 | 2005-09-29 | Air Water Chemical Inc | 熱硬化性樹脂の異物除去方法及び装置 |
JP2013043911A (ja) * | 2011-08-23 | 2013-03-04 | Asahi Kasei Chemicals Corp | ポリアセタールの製造方法 |
JP2017035670A (ja) * | 2015-08-12 | 2017-02-16 | 宇部興産株式会社 | 選別装置 |
-
2021
- 2021-05-20 CN CN202110549939.3A patent/CN115366293A/zh active Pending
-
2022
- 2022-05-17 WO PCT/JP2022/020540 patent/WO2022244774A1/ja active Application Filing
- 2022-05-17 JP JP2023522676A patent/JPWO2022244774A1/ja active Pending
- 2022-05-17 EP EP22804685.0A patent/EP4342916A1/en active Pending
- 2022-05-17 CN CN202280033892.8A patent/CN117295773A/zh active Pending
- 2022-05-19 TW TW111118708A patent/TW202307103A/zh unknown
-
2023
- 2023-11-13 US US18/507,699 patent/US20240075481A1/en active Pending
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5471155A (en) | 1977-11-18 | 1979-06-07 | Mitsui Fluorochemicals Co Ltd | Method for removing tramp material from fluorineecontaining resin powder |
JPH0474546A (ja) * | 1990-07-17 | 1992-03-09 | Mitsubishi Gas Chem Co Inc | 永久磁石式ロールセパレータ |
JP2003137922A (ja) * | 2001-07-06 | 2003-05-14 | Nippon Shokubai Co Ltd | 吸水性樹脂粉末、その製造方法およびその用途 |
JP2005021761A (ja) | 2003-06-30 | 2005-01-27 | Sumitomo Bakelite Co Ltd | 不純物の除去装置 |
JP2005066952A (ja) * | 2003-08-21 | 2005-03-17 | Daicel Chem Ind Ltd | プラスチック混合物の分別処理システム |
JP2005263985A (ja) | 2004-03-18 | 2005-09-29 | Air Water Chemical Inc | 熱硬化性樹脂の異物除去方法及び装置 |
JP2013043911A (ja) * | 2011-08-23 | 2013-03-04 | Asahi Kasei Chemicals Corp | ポリアセタールの製造方法 |
JP2017035670A (ja) * | 2015-08-12 | 2017-02-16 | 宇部興産株式会社 | 選別装置 |
Also Published As
Publication number | Publication date |
---|---|
EP4342916A1 (en) | 2024-03-27 |
CN117295773A (zh) | 2023-12-26 |
CN115366293A (zh) | 2022-11-22 |
US20240075481A1 (en) | 2024-03-07 |
JPWO2022244774A1 (ja) | 2022-11-24 |
TW202307103A (zh) | 2023-02-16 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP5243803B2 (ja) | 磁場および磁場傾斜改善ろ過用装置 | |
JP2018534121A (ja) | 常磁性物質及び反磁性物質用フィルタ | |
JP5280626B2 (ja) | 非磁性金属酸化物粉末における着磁性粒子の個数測定方法 | |
WO2022244774A1 (ja) | フッ素樹脂からの金属異物の除去方法及び金属異物が低減されたフッ素樹脂の製造方法 | |
US20060281194A1 (en) | Magnetic field and field gradient enhanced centrifugation solid-liquid separations | |
JPWO2018181046A1 (ja) | アトマイズ粉の製造方法及び磁心の製造方法 | |
US7681737B2 (en) | Magnetic separator apparatus | |
Arpagaus et al. | A Downer Reactor for Short‐time Plasma Surface Modification of Polymer Powders | |
KR20070107127A (ko) | 자기장 구배가 개선된 원심 분리용 장치 | |
JP2006341212A (ja) | 磁性異物類除去清掃装置 | |
JPWO2013027818A1 (ja) | 混合物の分離方法及び分離装置 | |
WO2002020125A1 (fr) | Dispositif filtrant magnetique | |
JP4953042B2 (ja) | 磁性体異物除去装置 | |
JP5320901B2 (ja) | 磁性金属異物の除去方法 | |
JP4293360B2 (ja) | 熱硬化性樹脂の異物除去方法及び装置 | |
Yu et al. | Magnetic molecularly imprinted polymer beads obtained by suspension polymerization for the adsorption of 2, 4, 6-trichlorophenol from an aqueous solution in a fixed-bed column | |
JP4760781B2 (ja) | 磁性金属異物の捕捉方法及び磁性金属異物の捕捉装置並びに被処理物の検査方法 | |
JP5152623B2 (ja) | 電子写真用キャリアの磁選機 | |
JP4301369B2 (ja) | 磁石体及びその磁石体を用いた箱又は磁選機 | |
JP5842294B2 (ja) | 混合物の分離方法 | |
Ohta et al. | Effects of ultrasound on behavior of fine solid particles in a solid-liquid mixture (Horizontal irradiation in a stationary solid-liquid mixture) | |
JPH037122B2 (ja) | ||
CN113369013A (zh) | 一种铁精粉磁选设备 | |
JP2022101735A (ja) | 石英ガラス原料粉の磁性体粉除去装置、及びこの磁性体粉除去装置を用いた磁性体粉除去方法 | |
JPH0259008A (ja) | ろ過処理法 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 22804685 Country of ref document: EP Kind code of ref document: A1 |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2023522676 Country of ref document: JP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 202280033892.8 Country of ref document: CN |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2022804685 Country of ref document: EP |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
ENP | Entry into the national phase |
Ref document number: 2022804685 Country of ref document: EP Effective date: 20231220 |