Classifications

• • 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
• • 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
  • C08F14/00—Homopolymers and copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen
  • C08F14/18—Monomers containing fluorine
  • C08F14/26—Tetrafluoroethene
• • 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
  • C08F214/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen
  • C08F214/18—Monomers containing fluorine
  • C08F214/26—Tetrafluoroethene
• • 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
  • C08F214/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen
  • C08F214/18—Monomers containing fluorine
  • C08F214/26—Tetrafluoroethene
  • C08F214/265—Tetrafluoroethene with non-fluorinated comonomers
• • 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
  • F16L9/00—Rigid pipes
  • F16L9/12—Rigid pipes of plastics with or without reinforcement

Definitions

• the present invention relates to a tube for semiconductor manufacturing equipment.
• Fluorine-containing polymers are used in a variety of fields because of their excellent heat resistance, chemical resistance, mechanical properties, electrical properties, surface properties, and the like. They are utilized as molding materials constituting components of pipes for transporting various fluids used in manufacturing equipment for electronic components such as semiconductors, chemicals, and pharmaceuticals, joint members (fittings) for pipes, storage containers, pumps, and filter housings.
• Patent Document 1 discloses a molded article made of a copolymer (PFA) of tetrafluoroethylene (TFE) and perfluoro(alkyl vinyl ether) (PAVE), the PFA having a PAVE content of 1 to 10 mol %, and having a flex life value, zero shear viscosity, and thermal weight loss each having a predetermined value.
• PFA a copolymer of tetrafluoroethylene (TFE) and perfluoro(alkyl vinyl ether)
• TFE tetrafluoroethylene
• PAVE perfluoro(alkyl vinyl ether)
• a tube for semiconductor manufacturing equipment comprising a fluoropolymer
• a tube for semiconductor manufacturing equipment wherein the fluoropolymer satisfies the following requirement A:
• the creep permanent deformation of the fluoropolymer is 4.5% or more
• the creep rate of the fluoropolymer in a tensile creep test is 2.60% or less
• the flexural modulus of the fluoropolymer is 1100 MPa or less
• the crystallinity of the fluoropolymer is at least 42.0%.
• a numerical range expressed using “to” means a range that includes the numerical values before and after “to” as the lower and upper limits.
• the term “unit” refers collectively to an atomic group derived from one molecule of the monomer directly formed by polymerization of the monomer, and an atomic group obtained by chemically converting a part of the atomic group.
• the content (mol %) of each unit relative to the total units contained in the polymer can be determined by analyzing the polymer by nuclear magnetic resonance spectroscopy, and can also be determined from the amounts of components used in the production of the polymer.
• TFE unit is a unit based on tetrafluoroethylene
• E unit is a unit based on ethylene.
• the tube for semiconductor manufacturing equipment of the present invention (hereinafter also referred to as “the present tube”) is a tube for semiconductor manufacturing equipment containing a fluoropolymer, and the fluoropolymer satisfies the following requirement A.
• the creep permanent deformation of the fluoropolymer is 4.5% or more
• the creep rate of the fluoropolymer in a tensile creep test is 2.60% or less
• the flexural modulus of the fluoropolymer is 1100 MPa or less
• the crystallinity of the fluoropolymer is 42.0% or more.
• the fluorine-containing polymer is a polymer containing units having fluorine atoms. From the viewpoint of the heat resistance of the tube, the fluoropolymer preferably has units based on tetrafluoroethylene (hereinafter also referred to as "TFE").
• TFE tetrafluoroethylene
• the fluoropolymer preferably has TFE units and units based on copolymerizable monomers (hereinafter also referred to as “other monomers”).
• other monomers include ethylene, propylene, perfluoro(alkyl vinyl ether) (hereinafter also referred to as "PAVE”), fluoroalkylethylene (hereinafter also referred to as "FAE”), and hexafluoropropylene.
• PFBE CH( CF2 ) 3F
• PFBE CH( CF2 ) 4F
• Other monomers also include vinyl chloride, vinylidene chloride, and vinyl fluoride.
• the other monomers include monomers having an oxygen-containing polar group.
• an oxygen-containing polar group an acid anhydride residue, a hydroxyl group, a carbonyl group-containing group, an acetal group, and an oxycycloalkane group are preferable, and an acid anhydride residue is more preferable.
• a monomer having a cyclic acid anhydride residue is preferable, and itaconic anhydride, citraconic anhydride, 5-norbornene-2,3-dicarboxylic anhydride, and maleic anhydride are more preferable.
• the fluoropolymer preferably has, as units based on other monomers, units based on at least one monomer selected from the group consisting of ethylene, propylene, fluoroalkylethylene and perfluoro(alkyl vinyl ether), more preferably has units based on at least one monomer selected from the group consisting of ethylene and fluoroalkylethylene, and even more preferably has units based on at least one monomer selected from the group consisting of ethylene and fluoroalkylethylene.
• One preferred embodiment of the fluoropolymer is one containing TFE units, ethylene units (hereinafter also referred to as "E units") and FAE units, and an embodiment consisting of TFE units, E units and FAE units is more preferred.
• the content of the TFE units is preferably from 40 to 64.9 mol %, more preferably from 45 to 60 mol %, and even more preferably from 50 to 60 mol %, based on the total of the TFE units, the E units and the FAE units.
• the content of E units is preferably from 35.0 to 59.9 mol %, more preferably from 35.5 to 54.5 mol %, and even more preferably from 36.0 to 49.0 mol %, based on the total of TFE units, E units and FAE units.
• the content of the FAE units is preferably from 0.1 to 5.0 mol %, more preferably from 0.5 to 4.5 mol %, and even more preferably from 1.0 to 4.0 mol %, based on the total of the TFE units, the E units and the FAE units.
• the content of the fluoropolymer is preferably from 50 to 100% by mass, more preferably from 75 to 100% by mass, and even more preferably from 90 to 100% by mass, based on the total mass of the present tube, in view of better effects of the present invention.
• Two or more kinds of fluorine-containing polymers may be used in combination.
• the fluoropolymer contained in this tube has a permanent creep set of 4.5% or more.
• the creep permanent set is a value obtained by performing a compression creep test in which a test specimen obtained by molding a fluoropolymer is compressed and deformed for 24 hours at a test temperature of 300°C and a test pressure of 140 kgf/ cm2 in accordance with ASTM D621, and then allowed to stand for 24 hours, and the value is calculated as the ratio of the dimensional change of the test specimen before and after the test to the dimension of the test specimen before the test (100 x dimensional change of test specimen before and after test/dimension of test specimen before test, unit: %).
• Detailed measurement conditions for the creep permanent set will be described in the Examples section below.
• the permanent creep set of the fluoropolymer is preferably at least 4.7, more preferably at least 5.0%, in view of better bondability to a joint.
• the permanent creep set of the fluoropolymer is preferably at most 10.0%, more preferably at most 8.5%, from the viewpoint of better liquid leakage resistance after joining with a joint.
• the creep permanent set of a fluoropolymer can be adjusted by increasing the molecular weight of the fluoropolymer, changing the crystallinity of the fluoropolymer, etc. Adjusting the molecular weight changes the entanglement of molecular chains, and allows the creep permanent set to be adjusted. Changing the ratio of constituent monomers changes the crystallinity, allowing the creep permanent set to be adjusted.
• the creep rate of the fluoropolymer is preferably at most 2.10%, more preferably at most 2.00%, in view of better bondability to a joint.
• the creep rate of the fluoropolymer is preferably at least 1.00%, more preferably at least 1.20%.
• the creep rate of the fluoropolymer can be adjusted, for example, by adjusting the melt flow rate (hereinafter also referred to as "MFR") of the fluoropolymer to be within the range described below (particularly, 1 to 20 g/10 min).
• the flexural modulus of the fluoropolymer contained in the present tube is 1100 MPa or less.
• the flexural modulus is a value (unit: MPa) calculated from a stress-strain curve obtained by measuring the stress and strain applied to a test specimen obtained by molding a fluoropolymer in accordance with ASTM D790, and performing a bending test at 23° C. Detailed conditions for measuring the flexural modulus are described in the Examples section below.
• the flexural modulus of the fluoropolymer is preferably 1,080 MPa or less, and more preferably 800 MPa or less, in view of better bondability to a joint.
• the flexural modulus of the fluoropolymer is preferably at least 300 MPa, and more preferably at least 400 MPa, in view of better pressure resistance.
• the flexural modulus of the fluoropolymer can be adjusted, for example, by adjusting the crystallinity of the fluoropolymer or by adjusting the MFR of the fluoropolymer.
• the degree of crystallinity increases when the content of units having 3 or more carbon atoms in the fluoropolymer is decreased, and decreases when the content of such units is increased.
• the flexural modulus of the fluoropolymer can be adjusted to within the above range.
• the flexural modulus of the fluoropolymer can be adjusted to within the above range by setting the MFR of the fluoropolymer to the range described below (particularly, 1 to 30 g/10 min).
• the melting point of the fluoropolymer is preferably 200° C. or higher, more preferably 215° C. or higher, and even more preferably 230° C. or higher, from the viewpoint of superior heat resistance.
• the upper limit of the melting point of the fluoropolymer is preferably 290° C. or lower, more preferably 280° C. or lower, and even more preferably 270° C. or lower, in view of superior moldability of the fluoropolymer.
• the MFR of the fluoropolymer is preferably from 1 to 100 g/10 min, more preferably from 1 to 50 g/10 min, even more preferably from 1 to 30 g/10 min, particularly preferably from 1 to 20 g/10 min, from the viewpoint of better moldability of the fluoropolymer and better mechanical strength and abrasion resistance of a molded article.
• the method for controlling the MFR of the fluoropolymer within the above range includes a method for adjusting the molecular weight of the fluoropolymer. The higher the molecular weight of the fluoropolymer, the smaller the MFR.
• the fluoropolymer can be produced by polymerizing the above-mentioned monomers by known methods such as bulk polymerization, solution polymerization, suspension polymerization, emulsion polymerization, etc. As the method for producing the fluoropolymer, solution polymerization is preferred. In the production of the fluoropolymer, in addition to the above-mentioned monomers, a polymerization initiator, a polymerization medium, a chain transfer agent, etc. can be used.
• At least one selected from the group consisting of alcohols, hydrocarbons, and hydrofluorocarbons is preferred from the viewpoint of higher chain transfer constant and higher stability of the end group of the fluoropolymer, at least one selected from the group consisting of alcohols and hydrocarbons is more preferred, and alcohols are even more preferred.
• the alcohols methanol or ethanol is preferred.
• methanol is more preferred from the viewpoint of reactivity and availability.
• Two or more types of chain transfer agents may be used.
• the amount of the chain transfer agent used is preferably 0.001 times or more, more preferably 0.005 times or more, and is preferably 5 times or less, more preferably 4 times or less, based on the amount of the monomer used, in terms of mass ratio.
• the present tube may contain components other than the above-mentioned fluoropolymer (hereinafter also referred to as "other components") within the range in which the effects of the present invention are fully exhibited.
• the other components include heat stabilizers, antioxidants, polymers other than fluorine-containing polymers, colorants, ultraviolet absorbers, fillers, crosslinking agents, and crosslinking assistants.
• the content of the other components is preferably 99 mass % or less, more preferably 50 mass % or less, and even more preferably 10 mass % or less, based on the total mass of the present tube.
• the other components may be used in combination of two or more kinds.
• the tube is a tubular member that is open at both ends.
• the thickness of the tube is preferably 4 mm or less, more preferably 3 mm or less, and even more preferably 2 mm or less, in order to achieve a better buckling resistance.
• the thickness of the tube is preferably 0.1 mm or more, more preferably 0.5 mm or more, in order to achieve a better buckling resistance.
• the thickness of the tube is a value obtained by dividing the difference between the outer diameter and the inner diameter of the tube in half.
• the buckling resistance means a property that does not cause a large deflection and is difficult to buckle when incorporated into a semiconductor manufacturing device (hereinafter, also referred to as "buckling resistance").
• the outer diameter of the present tube is preferably from 1 to 55 mm, more preferably from 1 to 40 mm, and even more preferably from 1 to 35 mm.
• the inner diameter of the present tube is shorter than the outer diameter and is preferably 0.5 to 50 mm, more preferably 0.5 to 40 mm, and even more preferably 0.5 to 35 mm.
• the tube is preferably produced by extrusion molding, since this allows the production of a tube with a uniform cross-sectional shape.
• the extruder used for extrusion molding includes an extruder equipped with a hopper, a screw, a cylinder, an adapter (a connecting portion between the screw and the die), and a die.
• the extruder may be a single-screw extruder or a twin-screw extruder.
• a vent hole may be provided in the cylinder, and volatile components generated from the fluoropolymer may be removed by opening the vent hole.
• the cylinder temperature is preferably 150 to 400°C, more preferably 180 to 390°C.
• the die temperature is preferably 200 to 380°C, more preferably 210 to 370°C.
• the present tube is a tube for semiconductor manufacturing equipment.
• the present tube has excellent joinability, is easy to join to a fitting, and is unlikely to leak after joining, and is therefore particularly suitable for use in semiconductor manufacturing equipment as a tube for transporting semiconductor chemicals or gases within the semiconductor manufacturing equipment.
• the semiconductor chemical liquid is a chemical liquid used in the manufacturing process of a semiconductor, and more specifically, examples of the semiconductor chemical liquid include an etching liquid, a developing liquid, a rinsing liquid, and a cleaning liquid.
• the above gases are gases supplied to semiconductor manufacturing equipment for use in the semiconductor manufacturing process, and more specifically, include raw material gases that are semiconductor film forming materials, process gases used in each process such as etching, developing, rinsing, and cleaning, and inert gases.
• the tube can also be used effectively as a liquid or gas transport tube in fields where reducing contamination from equipment is required, such as pharmaceutical manufacturing, medical equipment, analytical equipment, and food manufacturing.
• Examples 1 and 2 are working examples, and Examples 3 to 5 are comparative examples. However, the present invention is not limited to these examples.
• ⁇ Creep speed> The pellets of each example were melt molded at a temperature (230 to 360° C.) taking into consideration the melting point of the fluoropolymer contained in the pellets to produce a press sheet of 130 mm ⁇ 130 mm ⁇ 2 mm thickness.
• the press sheet produced was punched into a dumbbell shape (2 mm thick) according to ASTM D638 Type 4 to produce three samples.
• the creep rate of the obtained sample was measured using a tensile tester in accordance with ASTM D674. More specifically, after the sample was set in the tensile tester, a tensile creep test was performed for 150 hours at a stress of 70 kgf/ cm2 in an environment of 23°C ⁇ 3°C.
• the tube with the joint was submerged in a water tank, and air was pumped out at a pressure of 1 MPa using the air compressor. The presence or absence of air leakage from the joint surface between the joint and the tube was observed for 10 minutes.
• the tube and fitting joints were evaluated based on the ease of flaring the tube, the time required to join the tube and fitting, and the results of a liquid leakage test at the joint between the tube and fitting, and based on the following criteria. Five tubes were prepared for each example and the evaluation was performed.

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• Chemical & Material Sciences (AREA)
• Mechanical Engineering (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)

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• 2023
  • 2023-12-27 JP JP2024567928A patent/JPWO2024143464A1/ja active Pending
  • 2023-12-27 WO PCT/JP2023/046908 patent/WO2024143464A1/ja not_active Ceased
  • 2023-12-27 KR KR1020257018333A patent/KR20250127260A/ko active Pending
  • 2023-12-27 CN CN202380088590.5A patent/CN120418573A/zh active Pending
• 2025
  • 2025-04-28 US US19/190,944 patent/US20250257820A1/en active Pending

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