WO2022059501A1 - チューブの製造方法、押出成形機、押出成形用金型、巻取装置およびチューブ - Google Patents
チューブの製造方法、押出成形機、押出成形用金型、巻取装置およびチューブ Download PDFInfo
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- WO2022059501A1 WO2022059501A1 PCT/JP2021/032272 JP2021032272W WO2022059501A1 WO 2022059501 A1 WO2022059501 A1 WO 2022059501A1 JP 2021032272 W JP2021032272 W JP 2021032272W WO 2022059501 A1 WO2022059501 A1 WO 2022059501A1
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/27—Cleaning; Purging; Avoiding contamination
- B29C48/274—Cleaning; Purging; Avoiding contamination of the extruded articles
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
- B29C48/09—Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/022—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the choice of material
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
- B29C48/09—Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels
- B29C48/10—Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels flexible, e.g. blown foils
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/27—Cleaning; Purging; Avoiding contamination
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/28—Storing of extruded material, e.g. by winding up or stacking
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/30—Extrusion nozzles or dies
- B29C48/32—Extrusion nozzles or dies with annular openings, e.g. for forming tubular articles
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/355—Conveyors for extruded articles
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/88—Thermal treatment of the stream of extruded material, e.g. cooling
- B29C48/885—External treatment, e.g. by using air rings for cooling tubular films
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/88—Thermal treatment of the stream of extruded material, e.g. cooling
- B29C48/90—Thermal treatment of the stream of extruded material, e.g. cooling with calibration or sizing, i.e. combined with fixing or setting of the final dimensions of the extruded article
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C65/00—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
- B29C65/74—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by welding and severing, or by joining and severing, the severing being performed in the area to be joined, next to the area to be joined, in the joint area or next to the joint area
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L11/00—Hoses, i.e. flexible pipes
- F16L11/04—Hoses, i.e. flexible pipes made of rubber or flexible plastics
- F16L11/06—Hoses, i.e. flexible pipes made of rubber or flexible plastics with homogeneous wall
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/78—Thermal treatment of the extrusion moulding material or of preformed parts or layers, e.g. by heating or cooling
- B29C48/86—Thermal treatment of the extrusion moulding material or of preformed parts or layers, e.g. by heating or cooling at the nozzle zone
- B29C48/87—Cooling
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C49/00—Blow-moulding, i.e. blowing a preform or parison to a desired shape within a mould; Apparatus therefor
- B29C49/0015—Making articles of indefinite length, e.g. corrugated tubes
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C49/00—Blow-moulding, i.e. blowing a preform or parison to a desired shape within a mould; Apparatus therefor
- B29C49/0042—Blow-moulding, i.e. blowing a preform or parison to a desired shape within a mould; Apparatus therefor without using a mould
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- 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
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
- B29L2023/00—Tubular articles
- B29L2023/005—Hoses, i.e. flexible
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L11/00—Hoses, i.e. flexible pipes
- F16L11/04—Hoses, i.e. flexible pipes made of rubber or flexible plastics
- F16L11/042—Hoses, i.e. flexible pipes made of rubber or flexible plastics formed by bending a sheet and connecting the edges
Definitions
- the present disclosure relates to a tube manufacturing method, an extrusion molding machine, an extrusion molding die, a winding device, and a tube.
- Patent Document 1 describes, in a method for manufacturing a fluororesin tube in which a fluororesin or a resin admixture based on a fluororesin is melt-extruded and molded into a tube shape, clean air is flowed into the tube after or during tube molding.
- a method for manufacturing a particle-reducing fluororesin tube, which comprises purging particles in a tube, is described.
- a tube having a clean inner surface and excellent dimensional stability can be manufactured with high productivity, and is used in a method for manufacturing a tube and a method for manufacturing the tube, which can easily maintain a clean inner surface.
- the purpose is to provide the device. It is also an object of the present disclosure to provide a tube that can be handled while maintaining a clean inner surface.
- a melt-processable fluororesin extruded into a tube shape from a mold provided in an extruder is guided to a cooling device to be cooled, and then the cooled tube is cooled by using a winding device.
- a method for manufacturing a tube to be wound on a take-up reel in which gas is supplied from the tip of the tube wound on the take-up reel to the hollow portion of the tube and from a gas inlet provided in the mold. By discharging the gas in the hollow portion to the outside through the gas discharge hole provided in the mold, the gas is circulated through the hollow portion and the internal pressure of the hollow portion is made higher than the atmospheric pressure.
- a manufacturing method for keeping the pressure lower than 0.5 kgf / cm 2 is provided.
- the gas supplied to the hollow portion is a gas that has passed through a filter.
- the gas supplied to the hollow portion is air that has passed through a filter.
- the extrusion molding machine is provided with the mold and a backflow prevention device, and the mold has a resin discharge port for discharging the melt-processable fluororesin in a tube shape and a tube shape.
- the mold is provided with a resin discharge port for discharging the melt-processable fluororesin in a tube shape and a gas in a hollow portion of the tube-shaped melt-processable fluororesin in the mold.
- the take-up device is provided with a gas supply port for supplying gas to the hollow portion of the tube and a downstream side of the gas supply port, and is supplied from the gas supply port. It may be provided with one or more filters for removing contaminants in the gas, a tube connection port provided downstream of the filter to connect the tube, and a take-up reel around which the tube is wound. preferable.
- the take-up device is connected to a gas supply port for supplying gas to the hollow portion of the tube and the gas supply port, and the tip of the tube before winding is supplied with the gas. It is preferable to include a lead tube connected to the mouth and a take-up reel around which the tube and the lead tube are wound.
- the winding device includes a lead tube, and the tip of the lead tube is extruded from the mold while supplying the gas to the lead tube. It is preferable to supply the gas to the hollow portion of the tube by connecting to the tip of the resin.
- the tip of the lead tube is connected to the tip of the melt-processable fluororesin extruded from the mold in a state where the lead tube is fed from the winding device to the mold. After that, it is preferable to start continuous extruding of the melt-processable fluororesin from the mold and winding of the lead tube and the cooled tube.
- the melt-processable fluororesin is a tetrafluoroethylene / fluoroalkyl vinyl ether copolymer.
- an extrusion molding machine provided with a mold for forming a melt-processable fluorine resin into a tube shape and a backflow prevention device, and the mold discharges the melt-processable fluorine resin into a tube shape.
- a gas inlet for introducing the gas in the hollow portion of the tubular melt-processable fluororesin into the gas discharge hole provided in the mold, and the gas introduced from the gas inlet.
- An extrusion molding machine provided with a gas discharge hole for discharging to the outside of the mold, and to which the backflow prevention device for preventing the backflow of the gas is connected to the downstream side of the gas discharge hole of the mold. Is provided.
- the backflow prevention device is a bubbling device.
- an extrusion mold for forming a melt-processable fluorine resin into a tube shape
- the mold has a resin discharge port for discharging the melt-processable fluorine resin into a tube shape.
- a gas inlet for introducing the gas in the hollow portion of the tubular melt-processable fluororesin into a gas discharge hole provided in the mold, and the gas introduced from the gas inlet to the outside of the mold.
- an extrusion molding die comprising: a gas discharge hole for discharging, and the gas introduction port is formed so that the opening diameter increases from the gas discharge hole toward the gas introduction port.
- the gas introduction port has a reverse taper shape.
- the winding device for winding a tube is provided with a gas supply port for supplying gas to the hollow portion of the tube and a gas supply port on the downstream side of the gas supply port.
- One or more filters that remove contaminants in the gas supplied from the supply port a tube connection port that is provided downstream of the filter and connects the tube, and a take-up reel around which the tube is wound.
- a take-up device comprising.
- the winding device of the present disclosure includes two or more of the filters connected in series, and the filtration accuracy of the filters is different from each other. It is preferable that the winding device of the present disclosure further includes a rotary joint provided on the downstream side of the gas supply port and on the upstream side of the filter.
- a winding device for winding a tube, and is connected to a gas supply port for supplying gas to the hollow portion of the tube and the gas supply port, and the tube before winding.
- a winding device including a lead tube for connecting the tip of the lead tube to the gas supply port and a winding reel for winding the lead tube is provided.
- the length of the lead tube is preferably 3 m or more.
- a tube containing a melt-processable fluororesin both ends of which are sealed, and a hollow portion is filled with a gas that has passed a filter.
- the tubes of the present disclosure are preferably welded at both ends. In the tubes of the present disclosure, it is preferable that the inner surface of the tube has never come into contact with a gas that has not passed through the filter.
- the tubes of the present disclosure preferably have a length of 25 m or more.
- the tubes of the present disclosure are preferably wound on a take-up reel.
- a tube manufacturing method and a manufacturing method thereof capable of manufacturing a tube having a clean inner surface and excellent dimensional stability with high productivity and easily maintaining a clean inner surface.
- the device used for the above can be provided. Further, in the present disclosure, it is possible to provide a tube that can be handled while maintaining a clean inner surface.
- FIG. 1 is a schematic side view of a tube manufacturing apparatus.
- FIG. 2 is a schematic cross-sectional view of an extruder.
- FIG. 3 is a schematic cross-sectional view showing the shape of the gas introduction port of the conventional mold.
- FIG. 4 is a schematic cross-sectional view of a backflow prevention device provided in the extruder.
- FIG. 5 is a schematic front view of the winding device.
- FIG. 6 is a diagram for explaining an example of a method of connecting the tip of the lead tube to the tip of the melt-processable fluororesin extruded from the mold.
- FIG. 7 is a schematic cross-sectional view showing an embodiment of a tube in which both ends are welded.
- a melt-processable fluororesin is melted and extruded into a tube shape from a mold provided in an extruder, and melt-processed by being extruded into a tube shape from a mold provided in an extruder.
- the sex fluororesin is guided to a cooling device to be cooled, and then the cooled tube is wound on a take-up reel using a take-up device to manufacture the tube.
- gas is supplied to the hollow portion of the tube from the tip of the tube wound on the take-up reel, and the gas in the hollow portion is transferred to the mold from the gas inlet provided in the mold.
- the gas is circulated in the hollow part, and the internal pressure of the hollow part is kept higher than the atmospheric pressure and lower than 0.5 kgf / cm 2 . ing.
- the shape of the tube (the tube between the mold and the cooling device) before cooling and solidification can be maintained, and the contaminants contained in the hollow portion of the tube can be discharged from the hollow portion.
- the cooled tube is wound on the take-up reel, and by circulating gas from the take-up reel side toward the mold, the inner surface of the tube wound on the take-up reel is also formed. It can be kept clean. Even if the mold is corroded, the contaminants generated by the corrosion of the mold are discharged from the mold to the outside and do not adhere to the inner surface of the tube.
- Patent Document 1 describes that clean air is supplied into the tube from the tip of the delivered tube to perform a purge process.
- a conventional method it is difficult to remove contaminants (such as volatile substances generated from the melt-processable fluororesin) adhering to the inner surface of the tube.
- contaminants such as volatile substances generated from the melt-processable fluororesin
- the pollutant adheres to the melt-processable fluororesin in a molten state it adheres to the inner surface extremely strongly, and when trying to blow off the pollutant adhered by the gas flow, it is necessary to use a high-pressure gas flow.
- the tube before the melt-processable fluororesin in the molten state is cooled and solidified is very soft and the shape is liable to change.
- the melt-processable fluorine in a molten state extruded into a tube shape is maintained. It is possible to easily manufacture a tube having a clean inner surface and excellent dimensional stability while maintaining the shape of the resin.
- a take-up reel is used, and the cooled tube is taken up by the take-up reel, and gas is supplied from the tip of the taken-up tube, so that the inner surface is formed. It is clean and long tubes can be easily manufactured. Moreover, since the air does not flow into the hollow part of the tube during manufacturing, pollutants in the atmosphere do not adhere to the inner surface of the tube during manufacturing, and the clean inner surface does not need to be purged with a high-pressure gas flow. Is kept.
- the gas supplied from the tip of the wound tube is discharged to the outside through the mold.
- the mold used for extrusion molding of the melt-processable fluororesin may corrode. Contaminants such as metal components are generated from the corroded mold. According to the manufacturing method of the present disclosure, even if the mold is corroded, the contaminants generated by the corrosion of the mold are discharged from the mold to the outside and flow into the hollow portion of the tube extruded from the mold. Since there is no need to do so, a tube with a clean inner surface can be manufactured.
- pollutants include volatile substances generated from melt-processable fluororesins, metallic substances, particles, organic substances such as plasticizers existing in the atmosphere, and the like.
- FIG. 1 is a schematic side view of a tube manufacturing apparatus
- FIG. 2 is a schematic sectional view of an extruder
- FIG. 4 is a schematic sectional view of a backflow prevention device provided in the extruder
- FIG. 5 is a winding apparatus. It is a schematic front view of.
- the tube manufacturing apparatus 100 shown in FIG. 1 includes an extrusion molding machine 10 that melts a melt-processable fluororesin and extrudes it into a tube shape, a sizing die 40 that defines the outer diameter of the extruded molten tube, and a molten state.
- the cooling water tank 50 for cooling and solidifying the tube the take-up machine 60 for taking up the cooled melt-processable fluororesin tube, the take-up device 70 for taking up the tube sent out from the take-up machine, and the take-up device 70. It is provided with a gas supply device 80 for supplying gas.
- the melt-processable fluororesin charged from the hopper 11 of the extruder 10 is melted in the cylinder 12 of the extruder 10, and the screw 13 is rotated to melt the melt process.
- the fluororesin is extruded from the mold 20 into a tube shape.
- the melt-processable fluororesin in a molten state extruded into a tube shape passes through the sizing die 40, and its outer shape is defined.
- the melt-processable fluororesin that has passed through the sizing die 40 is cooled in the cooling water tank 50, then passes through a take-up machine 60 that takes up the cooled melt-processable fluororesin tube, and is wound by the take-up device 70. It is wound on the take-up reel 75 provided in the device.
- the take-up speed (line speed) at this time is generally 30 to 150 cm / min, and may be 30 to 120 cm / min.
- the molten tubular melt-processable fluororesin conveyed between the mold 20 and the sizing die 40 is particularly soft and easily changes in shape. Therefore, it is necessary to supply gas to the hollow portion of the tube at a pressure that can suppress the adhesion of contaminants to the inner surface of the tube while suppressing the deformation of the tube.
- the internal pressure (gauge pressure) of the hollow portion may be higher than the atmospheric pressure and lower than 0.5 kgf / cm 2 , but is preferably 0.4 kgf / cm 2 or less, and more preferably 0. It is 3 kgf / cm 2 or less, preferably 0.1 kgf / cm 2 or more, and more preferably 0.2 kgf / cm 2 or more.
- the extruder 10 is housed in a hopper 11 for charging a melt-processable fluororesin into a cylinder, a cylinder 12 for melting the melt-processable fluororesin, and a cylinder.
- the screw 13 for extruding the melt-processable fluororesin, the adapter 14 for connecting the cylinder and the mold, and the mold 20 for forming the extruded molten-processable fluororesin into a tube shape are provided. ..
- the mold 20 is provided with a resin discharge port 21 for discharging a melt-processable fluororesin in a tube shape and a gas in a hollow portion 2 of a tube-shaped melt-processable fluororesin 1 in the mold. It is provided with a gas introduction port 22 to be introduced into the gas discharge hole, and a gas discharge hole 23 to discharge the gas introduced from the gas introduction port to the outside of the mold.
- the extrusion molding machine 10 further includes a backflow prevention device 30, and the backflow prevention device 30 is connected to the gas discharge hole 23 of the mold 20 to discharge the gas to the outside of the extrusion molding machine 10 and to prevent the backflow of the gas. To prevent.
- FIG. 4 is a diagram showing an embodiment of the backflow prevention device 30.
- the backflow prevention device 30 shown in FIG. 4 is a bubbling device, and collects the gas introduction pipe 31 connected to the gas discharge hole 23 of the mold 20 and the pollutants in the gas introduced from the gas introduction pipe.
- the container 32 of 1 the pipe 33 connecting the first container and the second container, the second container 34 for bubbling the gas introduced from the pipe 33, and the liquid 35 contained in the second container.
- a pipe 36 for discharging the gas bubbling in the second container.
- One end of the pipe 33 is arranged at a position lower than the water surface of the liquid 35 contained in the second container 34, and one end of the pipe 36 is the water surface of the liquid 35 contained in the second container 34. It is located higher than the above.
- the height of the water surface of the liquid 35 can be appropriately adjusted, and the type of the liquid 35 is not particularly limited, and may be, for example, water.
- the liquid 35 contained in the second container 34 allows the gas existing in the pipe 33 and the gas existing in the second container 34 to freely flow. It is prevented.
- the liquid 35 contained in the second container 34 maintains the high pressure in the pipe 33. Since the pressure of the gas existing in the container is also equal to or higher than the atmospheric pressure, the gas is blown into the liquid 35 contained in the second container 34 from the pipe 33 to generate bubbles. The gas that has passed through the liquid 35 as bubbles is discharged to the outside of the extruder through the pipe 36.
- the backflow prevention device 30 is further provided with a first container 32, in which contaminants discharged from the extruder (particularly volatile substances generated from the melt-processable fluororesin) are trapped, and the piping 33 due to the contaminants is trapped. Blockage is prevented.
- the gas introduction pipe 31 may also be blocked by the pollutant, but by installing a heater in the gas introduction pipe 31 to heat the gas introduction pipe 31, adhesion of the pollutant can be prevented.
- the gas introduction port 22 is formed in a reverse taper shape. In this way, by forming the gas introduction port 22 so that the opening diameter increases from the gas discharge hole 23 toward the gas introduction port 22, the adhesion of pollutants to the periphery of the gas introduction port 22 is reduced.
- the shape of the gas introduction port 22 is not limited to the reverse taper shape, but may be a stepped shape.
- FIG. 3 is a schematic cross-sectional view showing the shape of the gas inlet of the conventional mold.
- the gas discharge hole 203 having a uniform diameter is provided, and the opening diameter of the gas introduction port 202 is the same as the diameter of the gas discharge hole.
- An exposed surface 204 surrounded by the resin discharge port 201 is formed. Gas collides with the exposed surface 204 from a direction perpendicular to the exposed surface 204, and gas tends to stay around the exposed surface 204. Therefore, pollutants (generated from melt-processable fluororesin) contained in the hollow portion of the tube. There is a problem that (such as volatile substances) easily adhere to the exposed surface 204. When contaminants are deposited on the exposed surface 204, they adhere to the melt-processable fluororesin in a molten state discharged from the resin discharge port 201 and are mixed as foreign matter in the finally obtained tube, causing molding defects.
- the mold 20 is formed so that the opening diameter increases from the gas discharge hole 23 toward the gas introduction port 22, so that the tube wound on the take-up reel is formed.
- the gas supplied from the tip reaches the mold 20
- the gas is smoothly introduced into the gas discharge hole 23 without staying around the gas introduction port 22 of the mold 20. Therefore, since the gas supplied to the tube is smoothly exhausted to the outside in a state containing contaminants, it is possible to effectively prevent the contaminants from adhering to the periphery of the gas inlet 22 and suppress the occurrence of molding defects. be able to.
- the opening diameter of the gas introduction port is not particularly limited, but as shown in FIG. 2, when the opening diameter of the gas introduction port 22 is substantially the same as the inner diameter of the resin discharge port 21, the exposed surface is almost eliminated and the pollutant gas is eliminated. Adhesion to the periphery of the introduction port 22 can be further prevented.
- the tube manufacturing device 100 includes a winding device 70.
- FIG. 5 is a diagram showing an embodiment of the winding device 70.
- the take-up device 70 shown in FIG. 5 is a take-up device for winding the tube 1, and is provided with a gas supply port 72 for supplying gas to the hollow portion of the tube 1 and a port downstream of the gas supply port 72.
- a filter 73 that removes contaminants in the gas supplied from the gas supply port 72, a tube connection port 74 that is provided on the downstream side of the filter 73 and connects the tube 1, and a reel around which the tube is wound. It is equipped with a reel 75.
- the take-up reel 75 is rotatably supported (shaft-supported) by a rotating shaft 77 provided on the support column 76 of the support frame, and the drive device 78 is driven to rotate with the rotating shaft 77, and the tube 1 is wound. Taken. One end of the tube 1 is connected to the tube connection port 74 via the lead tube 71. Gas is supplied from the tube connection port 74 to the hollow portion of the tube 1. The tube 1 is wound on a take-up reel 75 while flowing gas through the hollow portion.
- the gas supply port 72 is connected to the gas supply device 80.
- the gas supply device 80 may be a gas cylinder filled with high-pressure gas, a compressor, a blower, or the like.
- the gas supply device 80 may be provided with a needle valve (not shown) to adjust the gas supply pressure. The pressure may be adjusted to an appropriate level by opening and closing the needle valve while simply checking the amount of air bubbles generated in the backflow prevention device 30.
- the tube connection port 74 is connected to the gas supply port 72 via the filter 73.
- the filter 73 By supplying the gas that has passed through the filter 73 to the hollow portion of the tube 1, a tube having a clean inner surface can be manufactured.
- the type of gas supplied to the hollow portion of the tube 1 is not particularly limited, and may be an inert gas such as nitrogen gas, argon gas, or helium gas, air, oxygen gas, halogen gas, or the like. From the viewpoint of cost reduction, air is preferable.
- an inert gas such as nitrogen gas, argon gas, or helium gas, air, oxygen gas, halogen gas, or the like. From the viewpoint of cost reduction, air is preferable.
- a gas that has passed through a filter is used as the gas to be supplied to the hollow portion, a tube having a clean inner surface can be manufactured even if the type of gas is air.
- the filtration accuracy of the filter is not particularly limited, but is preferably 30 nm or less, more preferably 10 nm or less, still more preferably 5 nm or less, and particularly preferably 3 nm or less. If the filtration accuracy of the filter is too low, there are drawbacks that the gas resistance rises too much and the filter is easily clogged by contaminants in the gas. Therefore, the filtration accuracy of the filter is preferably 1 nm or more. ..
- the collection efficiency of the filter is not particularly limited, but as the filter, a filter that collects 99.99% or more of particles of 30 nm or more is preferable, and a filter that collects 99.99% or more of particles of 10 nm or more is more preferable. A filter that collects 99.99% or more of particles having a size of 5 nm or more is more preferable, and a filter that collects 99.99% or more of particles having a size of 3 nm or more is particularly preferable.
- the first filter 73a, the second filter 73b, and the third filter 73c are connected and provided in series.
- the number of filters is not particularly limited, and one or more filters can be provided.
- a gas having a higher degree of cleanliness can be easily supplied to the hollow portion of the tube 1.
- filters having different filtration accuracy or collection efficiency can be provided, whereby a gas having a higher degree of cleanliness can be easily supplied to the hollow portion of the tube 1. can do.
- a filter having a low filtration accuracy can be provided upstream, and a filter having a high filtration accuracy can be provided downstream thereof.
- a first filter 73a, a second filter 73b, and a third filter 73c are provided.
- the first filter 73a a filter having a filtration accuracy of more than 10 nm and 30 nm or less is used, and the second filter is used.
- the filter 73b a filter having a filtration accuracy of more than 5 nm and 10 nm or less can be used, and as the third filter 73c, a filter having a filtration accuracy of 5 nm or less can be used.
- a filter for removing impurities from the gas may be provided by a mechanism such as chemisorption.
- filters are sometimes referred to as chemical filters.
- the chemical filter can be installed upstream of the filter that physically removes impurities from the gas as described above.
- the take-up device 70 further includes a rotary joint 79 provided on the downstream side of the gas supply port 72 and on the upstream side of the filter.
- the gas introduced from the gas supply port 72 passes through the hollow portion of the rotary joint 79 and reaches the tube connection port 74, and the gas is supplied to the hollow portion of the tube 1.
- the gas that has passed through the rotary joint 79 may contain contaminants such as fine particles generated by friction caused by the rotation of the rotary joint 79.
- the filter 73 on the downstream side of the rotary joint 79, the contaminants generated from the rotary joint 79 can be filtered, so that the tube 1 can be pressed while supplying a gas having a higher degree of cleanliness to the hollow portion of the tube 1. It can be wound on the take-up reel 75.
- the take-up device 70 further includes a lead tube 71 having one end connected to the tube connection port 74 and the other end connected to the tube 1. Gas is supplied to the hollow portion of the lead tube 71 from the tube connection port 74, and gas is also supplied to the hollow portion of the tube 1 connected to the lead tube 71.
- one end of the lead tube 71 is connected to the tube 1, but before starting extrusion molding of the melt-processable fluororesin, one end of the lead tube 71 is connected to the tube 1. It has not been. While supplying gas to the lead tube 71 with the tip of the lead tube 71 exposed, the lead tube 71 is sent out from the take-up reel 75, and the lead tube 71 is inserted through the take-up machine 60, the cooling water tank 50, and the sizing die 40. And let it reach the front of the mold 20.
- the tip of the lead tube 71 is connected to the tip of the melt-processable fluororesin extruded from the mold 20.
- gas is supplied to the lead tube 71, and the tip of the lead tube 71 is connected to the tip of the melt-processable fluororesin extruded from the mold 20 while flowing out the gas from the tip of the lead tube 71.
- Gas is supplied to the hollow portion of the molten tube 1. Clean gas is continuously supplied to the hollow portion of the molten tube 1 connected to the tip of the lead tube 71 from the time when it is connected to the tip of the lead tube 71. Contact with the atmosphere on the inner surface of the tube can be minimized while maintaining the shape of the hollow portion.
- FIG. 6 is a diagram for explaining an example of a method of connecting the tip of the lead tube 71 to the tip of the melt-processable fluororesin extruded from the mold 20.
- the tip 71a of the lead tube 71 sent out from the winding device 70 is inserted into the tip 61a of the melt-processable fluororesin 61 in a molten state extruded from the mold 20.
- the tip 61a of the lead tube 71 With the tip 71a of the lead tube 71 inserted into the tip 61a of the melt-processable fluororesin 61, the tip 61a is sandwiched and welded to the tip 71a using tweezers or the like.
- the tip of the lead tube 71 and the tip of the melt-processable fluororesin can be connected to each other while allowing gas to flow out from the tip 71a of the lead tube 71.
- the melt-processable fluororesin After connecting the tip of the lead tube 71 to the tip of the melt-processable fluororesin extruded from the mold 20, the melt-processable fluororesin is continuously extruded from the mold 20 and cooled with the lead tube 71. The winding of the tube 1 is started. In this way, long tubes can be manufactured with high productivity while maintaining a clean inner surface.
- the length of the lead tube 71 may be the same as or longer than the distance from the winding device 70 to the mold 20, and is not particularly limited.
- the length of the lead tube 71 may be 3 m or more, 5 m or more, and 100 m or less.
- the material forming the lead tube 71 is not particularly limited as long as it is a material having the flexibility to be smoothly wound around the take-up reel. However, when a lead tube containing a melt-processable fluororesin is used, it is in a molten state. It is preferable because it is easily welded to a melt-processable fluororesin.
- the extrusion of the melt-processable fluororesin and the winding of the tube are stopped.
- the tube in which gas is sealed can be manufactured by welding and cutting any two points of the tube.
- the inner surface of the tube obtained by such a manufacturing method has never been in contact with the atmosphere and is extremely clean.
- a tube having a clean inner surface can be easily manufactured. Furthermore, when molding a melt-processable fluororesin while supplying a gas that has passed through a filter, clean gas is introduced into the tube without contacting the inner surface of the tube with a gas that has never passed through the filter. Can be enclosed in. Further, any two locations may be welded while maintaining the internal pressure at the time of molding, whereby the inner surface of the tube can be kept even more clean. The clean inner surface is maintained until the tube is cut to the desired length during use and air flows into the hollow through the cut.
- FIG. 7 is a schematic cross-sectional view showing an embodiment of a tube 1 in which both ends are welded.
- a welded portion 4 is provided around the cut surface 3 exposed at both ends, and the hollow portion of the tube 1 is sealed.
- the welding location of the tube is not particularly limited, but for example, if one location of the tube is welded between the mold 20 and the sizing die 40 and one location of the tube is welded in the vicinity of being connected to the lead tube 71, Tubes can be manufactured without waste.
- the melt-processable fluororesin of the tube at the portion to be welded is in a molten state, it can be welded by sandwiching it with tweezers or the like.
- the tube at the portion to be welded is cooled and solidified, it can be welded by heating it with a heat gun or the like to partially melt the welded portion and sandwiching it with tweezers or the like.
- the distance between the welding points is not particularly limited, and the welding points can be selected so that a tube having a desired length can be obtained. That is, according to the manufacturing method of the present disclosure, it is possible to easily manufacture a tube preferably 25 m or more, more preferably 30 m or more, still more preferably 40 m or more.
- the upper limit of the length is not particularly limited, but may be 500 m.
- the tube After welding any two points of the tube, the tube is completely wound on the take-up reel 75, and the take-up reel 75 is removed from the support stand to obtain the tube wound on the take-up reel.
- a gas that has passed through a filter having a filtration accuracy of 30 nm or less is preferable.
- the filtration accuracy of the filter is not particularly limited, but is preferably 10 nm or less, more preferably 5 nm or less, and further preferably 3 nm or less.
- the tube filled with gas that has passed through a filter with a filtration accuracy of 5 nm or less is filled with gas that has collected particles with a collection efficiency of 99% or more.
- the number of particles has a peak in the size of several tens of nm, and the number of particles in the size of several tens of nm in the atmosphere is said to be about tens of thousands to tens of millions / cc.
- the collection efficiency of the filter is 99%, the number of particles having a size of several tens of nm in the filtered gas is several hundred to several tens of thousands / cc, and if the collection efficiency is 99.99%, the number of particles is several hundred to several tens of thousands.
- the number of particles having a size of several tens of nm in the filtered gas is 1 to 1000 particles / cc.
- two filters having a collection efficiency of 99% are installed in series, the number of particles having a size of several tens of nm in the gas after filtration is 1 to 1000 / cc.
- the number of particles having a size of 5 nm or more can be reduced to 1000 particles / cc or less, preferably 500 particles / cc or less, and more preferably 100 particles / cc or less.
- the collection efficiency of a commercially available filter is determined by passing a large amount of contaminated gas and measuring the number of fine particles in the concentrated gas, and in principle, a tube in which the gas is enclosed. By recovering the enclosed gas and measuring the number of particles in the gas, the number of particles in the enclosed gas can be grasped.
- the internal space capacity of the tube is small, it is difficult to collect enough gas to concentrate to a measurable concentration in order to measure the number of particles in the gas in the tube.
- the inventors propose a method for measuring the number of fine particles existing inside a tube in a liquid.
- the measured particle size of the particle counter in the liquid is 30 nm or more, and in the manufacturing method of the present disclosure and the tube of the present disclosure, particles of this size are removed by a filter and are extremely low to the extent that they cannot be measured in principle. It is presumed to be the concentration.
- a tube having an extremely clean inner surface can be manufactured as compared with the case where the current tube manufacturing method is used. You can see what you can do.
- the method of manufacturing a tube in which both ends are welded has been described, but the method of sealing the tube is not limited to welding, and by installing a cap or the like at both ends, a filter is formed in the hollow portion. It is also possible to enclose the gas that has passed through. However, in order to obtain a tube in which the inner surface of the tube has never come into contact with a gas that has not passed through a filter, it is necessary to manufacture the tube by the above-mentioned manufacturing method. Therefore, a tube having a cleaner inner surface is used. If necessary, a tube in which both ends are welded is suitable.
- the melt-processable fluororesin that forms the tube is a fluororesin that has melt-processability.
- the melt processability means that a polymer can be melted and processed by using conventional processing equipment such as an extruder and an injection molding machine. Therefore, the melt-processable fluororesin usually has a melt flow rate of 0.01 to 500 g / 10 minutes as measured by the measuring method described later.
- the melt flow rate (MFR) of the fluororesin is preferably 0.5 to 100 g / 10 minutes, more preferably 1 to 50 g / 10 minutes, and further preferably 2 to 40 g / 10 minutes.
- MFR conforms to ASTM D-1238, with a die having a diameter of 2.1 mm and a length of 8 mm, a load of 5 kg, and an arbitrary temperature in the range of about 230 to 400 ° C, which is a general molding temperature of fluororesin. Measure at (eg, 372 ° C.).
- the melting point of the fluororesin is not particularly limited, but is preferably 100 to 324 ° C, more preferably 220 to 315 ° C.
- the melting point is a temperature corresponding to the maximum value in the heat of fusion curve when the temperature is raised at a rate of 10 ° C./min using a differential scanning calorimeter [DSC].
- melt-processable fluororesin examples include tetrafluoroethylene / fluoroalkyl vinyl ether copolymer, tetrafluoroethylene (TFE) / hexafluoropropylene (HFP) copolymer, TFE / ethylene copolymer [ETFE], and TFE /.
- Ethylene / HFP copolymer ethylene / chlorotrifluoroethylene (CTFE) copolymer [ECTFE], polychlorotrifluoroethylene [PCTFE], CTFE / TFE copolymer, polyvinylidenefluoride [PVdF], TFE / vinylidene
- CTFE chlorotrifluoroethylene
- PCTFE polychlorotrifluoroethylene
- VdF polyvinylidenefluoride
- VdF polyvinylidenefluoride
- VdF fluorolide copolymer
- VT fluorolide copolymer
- PVTC polyvinyl fluoride
- HFP / VdF copolymer and the like.
- melt-processable fluororesin a tetrafluoroethylene (TFE) / fluoroalkyl vinyl ether (FAVE) copolymer is preferable because it has excellent chemical resistance, heat resistance, and crack resistance.
- TFE tetrafluoroethylene
- FAVE fluoroalkyl vinyl ether
- the TFE / FAVE copolymer has a problem that it is difficult to manufacture a tube having a clean inner surface due to the high molding temperature.
- a tube containing a TFE / FAVE copolymer and having a clean inner surface can be produced with high productivity.
- the TFE / FAVE copolymer is not particularly limited, but a copolymer having a molar ratio of TFE units to FAVE units (TFE unit / FAVE unit) of 70/30 or more and less than 99/1 is preferable. A more preferable molar ratio is 70/30 or more and 98.9 / 1.1 or less, and a more preferable molar ratio is 80/20 or more and 98.9 / 1.1 or less. If the TFE unit is too small, the mechanical properties tend to deteriorate, and if it is too large, the melting point tends to be too high and the moldability tends to deteriorate.
- the TFE / FAVE copolymer contains 0.1 to 10 mol% of monomer units derived from TFE and a monomer copolymerizable with FAVE, and 90 to 99 to 99 in total of TFE units and FAVE units. It is also preferable that the copolymer is 9 mol%.
- TFE / FAVE copolymer at least one selected from the group consisting of only TFE units and FAVE units and the group consisting of TFE / HFP / FAVE copolymers is preferable, and TFE units and FAVE are preferable. Copolymers consisting only of units are more preferable.
- the melting point of the TFE / FAVE copolymer is preferably 280 to 322 ° C, more preferably 290 ° C or higher, further preferably 295 ° C or higher, particularly preferably 300 ° C or higher, and more preferably. It is 315 ° C or lower.
- the melting point can be measured using a differential scanning calorimeter [DSC].
- the glass transition temperature (Tg) of the TFE / FAVE copolymer is preferably 70 to 110 ° C, more preferably 80 ° C or higher, and more preferably 100 ° C or lower.
- the glass transition temperature can be measured by dynamic viscoelasticity measurement.
- the melt flow rate (MFR) of the TFE / FAVE copolymer at 372 ° C. is preferably 0.1 to 100 g / 10 minutes, more preferably 0.5 g / 10 minutes or more, still more preferably 1 g / g. It is 10 minutes or more, more preferably 80 g / 10 minutes or less, further preferably 40 g / 10 minutes or less, and particularly preferably 30 g / 10 minutes or less.
- the TFE / FAVE copolymer a copolymer having a small number of functional groups is preferable because a cleaner tube can be obtained and the moldability is excellent, and the total number of functional groups is 106 carbon atoms. It is preferably 400 or less per unit.
- the number of functional groups per 10 to 6 carbon atoms is more preferably 200 or less, further preferably 200 or less, particularly preferably 50 or less, and even more preferably 15 or less.
- the functional group is a functional group existing at the main chain end or the side chain end of the TFE / FAVE copolymer, and a functional group existing in the main chain or the side chain.
- Infrared spectroscopy can be used to identify the type of functional group and measure the number of functional groups.
- the number of functional groups is measured by the following method.
- the TFE / FAVE copolymer is melted at 340 to 350 ° C. for 30 minutes and compression molded to prepare a film having a thickness of 0.05 to 0.25 mm.
- This film is analyzed by Fourier transform infrared spectroscopic analysis to obtain an infrared absorption spectrum of the TFE / FAVE copolymer, and a difference spectrum from a base spectrum that is completely fluorinated and has no functional group. From the absorption peak of a specific functional group appearing in this difference spectrum, the number N of functional groups per 1 ⁇ 10 6 carbon atoms in the TFE / FAVE copolymer is calculated according to the following formula (A).
- N I ⁇ K / t (A)
- Table 1 shows the absorption frequency, molar absorption coefficient, and correction coefficient for the functional groups in the present disclosure.
- the molar extinction coefficient was determined from the FT-IR measurement data of the small molecule model compound.
- the number of functional groups of -COF is derived from the number of functional groups obtained from the absorption peak having an absorption frequency of 1883 cm -1 due to -CF 2 COF and the absorption peak having an absorption frequency of 1840 cm -1 due to -CH 2 COF. It is the total with the obtained number of functional groups.
- the functional group is introduced into the TFE / FAVE copolymer by, for example, a chain transfer agent or a polymerization initiator used in producing the TFE / FAVE copolymer.
- a chain transfer agent or a polymerization initiator used in producing the TFE / FAVE copolymer.
- a chain transfer agent or a polymerization initiator used in producing the TFE / FAVE copolymer.
- -CH 2 OH is attached to the end of the main chain of the TFE / FAVE copolymer.
- the functional group is introduced into the side chain terminal of the TFE / FAVE copolymer.
- the TFE / FAVE copolymer having the number of functional groups within the above range can be obtained. That is, the TFE / FAVE copolymer is preferably fluorinated. It is also preferable that the TFE / FAVE copolymer has a -CF 3 terminal group.
- the above fluorination treatment can be performed by contacting the non-fluorinated TFE / FAVE copolymer with the fluorine-containing compound.
- the fluorine-containing compound is not particularly limited, and examples thereof include a fluorine radical source that generates fluorine radicals under fluorination treatment conditions.
- a fluorine radical source that generates fluorine radicals under fluorination treatment conditions.
- the fluorine radical source include F 2 gas, CoF 3 , AgF 2 , UF 6 , OF 2 , N 2 F 2 , CF 3 OF, and halogen fluoride (for example, IF 5 , ClF 3 ).
- the fluorine radical source such as the F 2 gas may have a concentration of 100%, but from the viewpoint of safety, it is preferably mixed with an inert gas and diluted to 5 to 50% by mass before use. It is more preferable to dilute it to about 30% by mass before use.
- the inert gas include nitrogen gas, helium gas, argon gas and the like, but nitrogen gas is preferable from the economical point of view.
- the conditions for the fluorination treatment are not particularly limited, and the melted TFE / FAVE copolymer may be brought into contact with the fluorine-containing compound, but usually, it is preferably below the melting point of the TFE / FAVE copolymer. Can be carried out at a temperature of 20 to 220 ° C, more preferably 100 to 200 ° C.
- the fluorination treatment is generally carried out for 1 to 30 hours, preferably 5 to 25 hours.
- the fluorination treatment is preferably such that the non-fluorinated TFE / FAVE copolymer is brought into contact with a fluorine gas (F 2 gas).
- the TFE / FAVE copolymer is produced by a conventionally known method such as emulsion polymerization or suspension polymerization by appropriately mixing a monomer as a constituent unit thereof or an additive such as a polymerization initiator. Can be done.
- the outer diameter of the tube is not particularly limited, but may be 2 to 100 mm, 3 to 100 mm, or 5 to 50 mm.
- the thickness of the tube may be 0.1 to 10 mm and may be 0.3 to 5 mm.
- the tube of the present disclosure can be suitably used as a tube for chemical liquid piping for circulating chemical liquid, and can be particularly preferably used as a tube for chemical liquid piping used for transferring high-purity chemical liquid for manufacturing semiconductor devices.
- the tube of the present disclosure has the above-mentioned structure, almost no contaminants adhere to the inner surface, and it is difficult to contaminate ultrapure water or high-purity chemicals used for manufacturing semiconductor devices. Since the tube of the present disclosure has such an effect, it is preferable that the tube is a tube for piping the chemical solution for circulating the chemical solution.
- the chemical solution include chemical solutions used for semiconductor production, and examples thereof include chemical solutions such as ammonia water, ozone water, hydrogen peroxide solution, hydrochloric acid, sulfuric acid, resist solution, thinner solution, and developer solution.
- the tube of the present disclosure can be used, for example, as a tube used in a semiconductor manufacturing facility such as a semiconductor manufacturing chemical supply line, a semiconductor manufacturing chemical liquid supply facility, a semiconductor cleaning device, a coater developer, or a semiconductor manufacturing device.
- a semiconductor manufacturing facility such as a semiconductor manufacturing chemical supply line, a semiconductor manufacturing chemical liquid supply facility, a semiconductor cleaning device, a coater developer, or a semiconductor manufacturing device.
- a high-purity chemical solution can be reliably supplied to a point of use.
- a semiconductor device having a line width of 5 nm or less is manufactured, defect defects due to particles and metal contaminants of the semiconductor device are reduced, and the yield in the manufacture of the semiconductor device is improved. Can be expected.
- the MFR is a copolymer of a copolymer that flows out from a nozzle having an inner diameter of 2.1 mm and a length of 8 mm per 10 minutes under a load of 372 ° C. and 5 kg using a melt indexer (manufactured by Yasuda Seiki Seisakusho Co., Ltd.) according to ASTM D1238. It was determined by measuring the mass (g / 10 minutes).
- the melting point was determined as the temperature corresponding to the maximum value in the heat of fusion curve when the temperature was raised at a rate of 10 ° C./min using a differential scanning calorimeter [DSC].
- the length of the unstretched tube was measured and evaluated according to the following criteria. In the experimental example in which a tube of 20 m or more was obtained, continuous molding of the tube was possible, and a non-stretched tube could be manufactured with high productivity. In the experimental example in which a tube of less than 20 m was obtained, the tube extruded from the mold 20 was torn between the mold 20 and the sizing die 40, and continuous molding was impossible. Evaluation criteria ⁇ : The tube length was 20 m or more ⁇ : The tube length was less than 20 m
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Abstract
Description
また、本開示では、清浄な内面を保った状態で取り扱うことができるチューブを提供することを目的とする。
本開示の製造方法において、前記中空部に供給するガスが、フィルターを通過させた空気であることが好ましい。
本開示の製造方法において、前記溶融加工性フッ素樹脂の押し出しを停止した後、チューブの任意の二箇所を溶着し、切断することによって、ガスが封入されているチューブを製造することが好ましい。
本開示の製造方法において、前記押出成形機が、前記金型および逆流防止装置を備えており、前記金型が、前記溶融加工性フッ素樹脂をチューブ状に吐出する樹脂吐出口と、チューブ状の前記溶融加工性フッ素樹脂の中空部のガスを、前記金型に設けられたガス排出孔に導入するガス導入口と、前記ガス導入口から導入した前記ガスを前記金型の外部に排出するガス排出孔と、を備えており、前記金型の前記ガス排出孔の下流側に、前記ガスの逆流を防止する前記逆流防止装置が接続されていることが好ましい。
本開示の製造方法において、前記金型が、前記溶融加工性フッ素樹脂をチューブ状に吐出する樹脂吐出口と、チューブ状の前記溶融加工性フッ素樹脂の中空部のガスを、前記金型に設けられたガス排出孔に導入するガス導入口と、前記ガス導入口から導入した前記ガスを前記金型の外部に排出するガス排出孔と、を備えており、前記ガス導入口が、前記ガス排出孔から前記ガス導入口に向かって、開口径が大きくなるように形成されていることが好ましい。
本開示の製造方法において、前記巻取装置が、前記チューブの中空部にガスを供給するガス供給口と、前記ガス供給口よりも下流側に設けられており、前記ガス供給口から供給されるガス中の汚染物質を除去する1個以上のフィルターと、前記フィルターよりも下流側に設けられており、前記チューブを接続するチューブ接続口と、前記チューブを巻き付ける巻取リールと、を備えることが好ましい。
本開示の製造方法において、前記巻取装置が、前記チューブの中空部にガスを供給するガス供給口と、前記ガス供給口に接続されており、巻き取る前の前記チューブの先端を前記ガス供給口と接続するリードチューブと、前記チューブおよび前記リードチューブを巻き付ける巻取リールと、を備えることが好ましい。
本開示の製造方法において、前記巻取装置が、リードチューブを備えており、前記リードチューブに前記ガスを供給しながら、前記リードチューブの先端を、前記金型から押し出された前記溶融加工性フッ素樹脂の先端と接続することにより、前記チューブの中空部に前記ガスを供給することが好ましい。
本開示の製造方法において、前記リードチューブを、前記巻取装置から前記金型まで送り出した状態で、前記リードチューブの先端を、前記金型から押し出された前記溶融加工性フッ素樹脂の先端と接続した後、前記金型からの前記溶融加工性フッ素樹脂の連続的な押し出し、および、前記リードチューブおよび冷却された前記チューブの巻き取りを開始することが好ましい。
本開示の製造方法において、前記溶融加工性フッ素樹脂が、テトラフルオロエチレン/フルオロアルキルビニルエーテル共重合体であることが好ましい。
本開示の巻取装置は、前記ガス供給口よりも下流側であって、前記フィルターよりも上流側に設けられた回転継手をさらに備えることが好ましい。
本開示のチューブにおいて、前記チューブの内面が、フィルターを通過させていないガスと接触したことがないことが好ましい。
本開示のチューブは、25m以上の長さを有することが好ましい。
本開示のチューブは、巻取リールに巻かれていることが好ましい。
また、本開示では、清浄な内面を保った状態で取り扱うことができるチューブを提供することができる。
N=I×K/t (A)
I:吸光度
K:補正係数
t:フィルムの厚さ(mm)
従って、たとえば、-COFの官能基数とは、-CF2COFに起因する吸収周波数1883cm-1の吸収ピークから求めた官能基数と、-CH2COFに起因する吸収周波数1840cm-1の吸収ピークから求めた官能基数との合計である。
PFA(1):ダイキン工業製 ネオフロン(登録商標) PFA AP-230SH
テトラフルオロエチレン/パーフルオロ(プロピルビニルエーテル)共重合体
メルトフローレート(MFR)2.0g/10min
融点307℃
(フッ素樹脂チューブの成形)
PFA(1)を用い、図1に示すチューブ製造装置を用いて、表2に示す成形条件にて外径6.35mm、内径4.35mmの無延伸チューブを製造した。押出成形機10として、スクリュ径φ30mmの溶融押出成形機(田辺プラスチックス社製)を使用した。評価方法を以下に示す。また、評価結果を表2に示す。
巻取リール75に巻き取られたチューブの先端からチューブの中空部にガスを供給し、バブリング装置(逆流防止装置30)中で発生する気泡の有無を確認した。気泡の発生は、供給したガスが、金型20に設けられたガス排出孔を通して、金型20の外部に排出されていることを意味する。
評価基準
〇:気泡が確認できた
×:気泡が確認できなかった
無延伸チューブの長さを測定し、以下の基準で評価した。20m以上のチューブが得られた実験例においては、チューブの連続成形が可能であり、高い生産性で無延伸チューブを製造できた。20m未満のチューブしか得られなかった実験例においては、金型20とサイジングダイ40との間で、金型20から押し出されたチューブが破れ、連続成形が不可能であった。
評価基準
〇:チューブ長が20m以上であった
×:チューブ長が20m未満であった
図1に示す冷却装置(冷却水槽)50と引取機60との間に外径測定器(KEYENCE製、商品名LS-9030)を設置し、得られたチューブのうち、任意の20m分の範囲の外径を測定し、以下の基準で評価した。
評価基準
〇:測定した範囲のチューブの全部の外径が6.35±0.10mmの範囲内であった
×:測定した範囲のチューブの一部の外径が6.35±0.10mmの範囲外であった
2 中空部
100 チューブ製造装置
10 押出成形機
20 金型
30 逆流防止装置
40 サイジングダイ
50 冷却装置(冷却水槽)
60 引取機
70 巻取装置
71 リードチューブ
80 ガス供給装置
Claims (25)
- 押出成形機に備えられた金型からチューブ状に押し出された溶融加工性フッ素樹脂を、冷却装置に導いて冷却した後、巻取装置を用いて、冷却されたチューブを巻取リールに巻き取るチューブの製造方法であって、
前記巻取リールに巻き取られた前記チューブの先端から前記チューブの中空部にガスを供給し、前記金型に設けられたガス導入口から、前記中空部のガスを、前記金型に設けられたガス排出孔を通して、外部に排出することによって、前記中空部にガスを流通させるとともに、前記中空部の内圧を、大気圧よりも高く、0.5kgf/cm2よりも低い圧力に保つ製造方法。 - 前記中空部に供給するガスが、フィルターを通過させたガスである請求項1に記載の製造方法。
- 前記中空部に供給するガスが、フィルターを通過させた空気である請求項1または2に記載の製造方法。
- 前記溶融加工性フッ素樹脂の押し出しを停止した後、チューブの任意の二箇所を溶着し、切断することによって、ガスが封入されているチューブを製造する請求項1~3のいずれかに記載の製造方法。
- 前記押出成形機が、前記金型および逆流防止装置を備えており、
前記金型が、前記溶融加工性フッ素樹脂をチューブ状に吐出する樹脂吐出口と、チューブ状の前記溶融加工性フッ素樹脂の中空部のガスを、前記金型に設けられたガス排出孔に導入するガス導入口と、前記ガス導入口から導入した前記ガスを前記金型の外部に排出するガス排出孔と、を備えており、
前記金型の前記ガス排出孔の下流側に、前記ガスの逆流を防止する前記逆流防止装置が接続されている
請求項1~4のいずれかに記載の製造方法。 - 前記金型が、前記溶融加工性フッ素樹脂をチューブ状に吐出する樹脂吐出口と、チューブ状の前記溶融加工性フッ素樹脂の中空部のガスを、前記金型に設けられたガス排出孔に導入するガス導入口と、前記ガス導入口から導入した前記ガスを前記金型の外部に排出するガス排出孔と、を備えており、
前記ガス導入口が、前記ガス排出孔から前記ガス導入口に向かって、開口径が大きくなるように形成されている
請求項1~5のいずれかに記載の製造方法。 - 前記巻取装置が、
前記チューブの中空部にガスを供給するガス供給口と、
前記ガス供給口よりも下流側に設けられており、前記ガス供給口から供給されるガス中の汚染物質を除去する1個以上のフィルターと、
前記フィルターよりも下流側に設けられており、前記チューブを接続するチューブ接続口と、
前記チューブを巻き付ける巻取リールと、
を備える請求項1~6のいずれかに記載の製造方法。 - 前記巻取装置が、
前記チューブの中空部にガスを供給するガス供給口と、
前記ガス供給口に接続されており、巻き取る前の前記チューブの先端を前記ガス供給口と接続するリードチューブと、
前記チューブおよび前記リードチューブを巻き付ける巻取リールと、
を備える請求項1~7のいずれかに記載の製造方法。 - 前記巻取装置が、リードチューブを備えており、前記リードチューブに前記ガスを供給しながら、前記リードチューブの先端を、前記金型から押し出された前記溶融加工性フッ素樹脂の先端と接続することにより、前記チューブの中空部に前記ガスを供給する請求項1~8のいずれかに記載の製造方法。
- 前記リードチューブを、前記巻取装置から前記金型まで送り出した状態で、前記リードチューブの先端を、前記金型から押し出された前記溶融加工性フッ素樹脂の先端と接続した後、前記金型からの前記溶融加工性フッ素樹脂の連続的な押し出し、および、前記リードチューブおよび冷却された前記チューブの巻き取りを開始する、請求項9に記載の製造方法。
- 前記溶融加工性フッ素樹脂が、テトラフルオロエチレン/フルオロアルキルビニルエーテル共重合体である請求項1~10のいずれかに記載の製造方法。
- 溶融加工性フッ素樹脂をチューブ状に成形する金型および逆流防止装置を備える押出成形機であって、
前記金型が、前記溶融加工性フッ素樹脂をチューブ状に吐出する樹脂吐出口と、前記チューブ状の溶融加工性フッ素樹脂の中空部のガスを、前記金型に設けられたガス排出孔に導入するガス導入口と、前記ガス導入口から導入した前記ガスを前記金型の外部に排出するガス排出孔と、を備えており、
前記金型の前記ガス排出孔の下流側に、前記ガスの逆流を防止する前記逆流防止装置が接続されている
押出成形機。 - 前記逆流防止装置が、バブリング装置である請求項12に記載の押出成形機。
- 溶融加工性フッ素樹脂をチューブ状に成形する押出成形用金型であって、
前記金型が、前記溶融加工性フッ素樹脂をチューブ状に吐出する樹脂吐出口と、前記チューブ状の溶融加工性フッ素樹脂の中空部のガスを、前記金型に設けられたガス排出孔に導入するガス導入口と、前記ガス導入口から導入した前記ガスを前記金型の外部に排出するガス排出孔と、を備えており、
前記ガス導入口が、前記ガス排出孔から前記ガス導入口に向かって、開口径が大きくなるように形成されている
押出成形用金型。 - 前記ガス導入口が、逆テーパー状である請求項14に記載の押出成形用金型。
- チューブを巻き取る巻取装置であって、
前記チューブの中空部にガスを供給するガス供給口と、
前記ガス供給口よりも下流側に設けられており、前記ガス供給口から供給されるガス中の汚染物質を除去する1個以上のフィルターと、
前記フィルターよりも下流側に設けられており、前記チューブを接続するチューブ接続口と、
前記チューブを巻き付ける巻取リールと、
を備える巻取装置。 - 直列に連結された2個以上の前記フィルターを備え、前記フィルターのろ過精度がお互いに異なる請求項16に記載の巻取装置。
- 前記ガス供給口よりも下流側であって、前記フィルターよりも上流側に設けられた回転継手をさらに備える請求項16または17に記載の巻取装置。
- チューブを巻き取る巻取装置であって、
前記チューブの中空部にガスを供給するガス供給口と、
前記ガス供給口に接続されており、巻き取る前の前記チューブの先端を前記ガス供給口と接続するリードチューブと、
前記リードチューブを巻き付ける巻取リールと、
を備える巻取装置。 - 前記リードチューブの長さが、3m以上である請求項19に記載の巻取装置。
- 溶融加工性フッ素樹脂を含有するチューブであって、両末端が封止されており、中空部にフィルターを通過させたガスが封入されているチューブ。
- 両末端が溶着されている請求項21に記載のチューブ。
- 前記チューブの内面が、フィルターを通過させていないガスと接触したことがない請求項21または22に記載のチューブ。
- 25m以上の長さを有する請求項21~23のいずれかに記載のチューブ。
- 巻取リールに巻かれている請求項21~24のいずれかに記載のチューブ。
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