阅读说明：本技术 导电性熔接材料及其制造方法 (Conductive welding material and method for producing same ) 是由 伊丹宏贵 山本弘和 野口勇 于 2019-01-31 设计创作，主要内容包括：本发明的熔接材料由在氟树脂中分散有碳纳米管的氟树脂组合物形成,氟树脂组合物含有0.01～2.0质量％的碳纳米管。(The welding material is formed by a fluororesin composition dispersed with carbon nano tubes in fluororesin, and the fluororesin composition contains 0.01-2.0 mass% of the carbon nano tubes.)

1. A fusion splice material, characterized by:

is formed by fluororesin composition dispersed with carbon nano-tube in fluororesin,

the fluororesin composition contains 0.01 to 2.0 mass% of carbon nanotubes.

2. The fusion material of claim 1, wherein:

the carbon nanotubes have an average length of 50 μm or more.

3. A fusion material according to claim 1 or 2, wherein:

has 1 × 10^-1～1×10⁸Volume resistivity of Ω · cm.

4. A weld material according to any one of claims 1 to 3, wherein:

the fluororesin contains at least 1 selected from the group consisting of Polytetrafluoroethylene (PTFE), modified polytetrafluoroethylene (modified PTFE), tetrafluoroethylene/perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene/hexafluoropropylene copolymer (FEP), ethylene/tetrafluoroethylene copolymer (ETFE), ethylene/chlorotrifluoroethylene copolymer (ECTFE), Polychlorotrifluoroethylene (PCTFE), polyvinylidene fluoride (PVDF), and polyvinyl fluoride (PVF).

5. The fusion material according to any one of claims 1 to 4, wherein:

the fluororesin of the fluororesin composition has an average particle diameter of 500 μm or less.

6. The fusion material according to any one of claims 1 to 5, wherein:

is used for the bonding part of the fluororesin and the fluororesin.

7. A fluid treatment device, characterized by:

a welding material according to any one of claims 1 to 6, wherein the joint between the fluororesin and the fluororesin is formed.

8. A semiconductor manufacturing apparatus, a medicine conveying apparatus, a chemical manufacturing apparatus, or a chemical conveying apparatus, characterized in that:

comprising the fluid treatment device of claim 7.

9. A method for producing the welding material according to any one of claims 1 to 6, comprising:

and a step of compression molding the fluororesin composition in which the carbon nanotubes are dispersed in the fluororesin.

10. A method for producing the welding material according to any one of claims 1 to 6, comprising:

a step of preparing a fluororesin composition in which carbon nanotubes are dispersed in a fluororesin selected from PTFE and modified PTFE;

a step of putting the fluororesin composition into a mold, and compressing the fluororesin composition under pressure to produce a preform;

a step of firing the preform at a temperature not lower than the melting point of the fluororesin composition to produce a molded body; and

and processing the molded body to produce a fusion material.

11. A method for producing the welding material according to any one of claims 1 to 6, comprising:

a step of preparing a fluororesin composition in which carbon nanotubes are dispersed in a fluororesin other than PTFE and modified PTFE;

heating the fluororesin composition, and then compressing the heated fluororesin composition under pressure to obtain a molded article; and

and processing the molded body to obtain a fusion material.

Technical Field

The present invention relates to a conductive welding material for a fluororesin and a method for producing the same, and more particularly, to a conductive welding material for a fluororesin having excellent antistatic performance, preventing elution of impurities (metal ions, organic substances, and the like), and exhibiting excellent welding strength, and a method for producing the same.

Background

Fluororesin is excellent in chemical resistance, stain resistance and the like, and is often used as a material for parts and the like for circulating corrosive fluids, pure water, chemical solutions and the like in semiconductor manufacturing apparatuses, pharmaceutical manufacturing apparatuses and the like.

However, since the fluororesin is generally classified as an insulating material, a member made of the fluororesin is electrically charged by friction when it comes into contact with a fluid.

Therefore, a technique of mixing a fluororesin with a conductive material such as carbon black or iron powder to impart conductivity to the fluororesin is known, but it is known that since the conductive material comes into contact with the fluid, metal ions, organic substances, and the like flow out to the fluid, and the fluid is contaminated.

Patent document 1 discloses a fluid device having a fluid flow path formed of a fluororesin material containing Carbon nanotubes (hereinafter, also referred to as "CNTs") having a fiber length of 50 to 150 μm and a fiber diameter of 5 to 20nm in a proportion of 0.020 to 0.030 wt% (see claim 1, [0008] to [0009], and [0033] of patent document 1), which can suppress static electricity generated by friction between the fluid flow path and the fluid and contamination of the fluid caused by contact between the fluid flow path and the fluid.

Disclosure of Invention

Technical problem to be solved by the invention

The fluid flow path formed of the fluororesin material of patent document 1 is excellent in fluid electrification preventing performance and fluid contamination preventing performance. However, when a plurality of fluid channels are connected by the plurality of fluid channels, and the length of the channels is increased or a wider channel is formed, and further, various shapes are formed, the treatment of the connection portion of the plurality of channels becomes a problem.

If no treatment is performed, leakage occurs at the joint, and in order to prevent leakage, a material called a fusion material is generally melted and the joint is sealed to reinforce the joint. The fluororesin material itself may be considered as a fusion-bonding material (bonding material or sealing material). However, the fluororesin itself has insufficient conductivity, and thus has a problem of lowering antistatic properties.

When a conductive substance such as carbon fiber is added to a fluororesin material in order to impart conductivity, it is usually necessary to add 5% by weight or more of the conductive substance in order to obtain sufficient conductivity. However, such materials are generally not suitable as welding materials because of insufficient welding strength and poor stain resistance.

The purpose of the present invention is to provide a fluororesin-related conductive welding material that has excellent antistatic properties, prevents elution of impurities (metal ions, organic substances, and the like), and exhibits excellent welding strength, and a method for producing the same.

Technical solution for solving technical problem

The present inventors have conducted extensive studies and, as a result, have found that when a fluororesin composition in which a specific amount of carbon nanotubes is dispersed in a fluororesin is used, a welding material having excellent antistatic performance, preventing elution of impurities (metal ions, organic substances, and the like), and exhibiting excellent welding strength can be obtained. Further, they have found that such a fusion-spliced material can be applied to various apparatuses such as a semiconductor manufacturing apparatus and a pharmaceutical manufacturing apparatus, and have completed the present invention.

The present specification may include the following modes.

[1] A welding material is formed by a fluororesin composition in which carbon nanotubes are dispersed in a fluororesin, wherein the fluororesin composition contains 0.01-2.0 mass% of the carbon nanotubes.

[2] The fusion material according to claim 1, wherein the carbon nanotubes have an average length of 50 μm or more.

[3]A welding material as described in 1 or 2 above, having 1 × 10^-1～1×10⁸Volume resistivity of Ω · cm.

[4] The welding material according to any one of claims 1 to 3, wherein the fluororesin contains at least 1 selected from the group consisting of Polytetrafluoroethylene (PTFE), modified polytetrafluoroethylene (modified PTFE), tetrafluoroethylene/perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene/hexafluoropropylene copolymer (FEP), ethylene/tetrafluoroethylene copolymer (ETFE), ethylene/chlorotrifluoroethylene copolymer (ECTFE), Polychlorotrifluoroethylene (PCTFE), polyvinylidene fluoride (PVDF), and polyvinyl fluoride (PVF).

[5] The welding material according to any one of the above 1 to 4, wherein the fluororesin of the fluororesin composition has an average particle diameter of 500 μm or less.

[6] The welding material according to any one of the above 1 to 5, which is used for a bonding portion between a fluororesin and a fluororesin.

[7] A fluid treatment apparatus comprising the welding material according to any one of 1 to 6 above at a bonding portion between a fluororesin and a fluororesin.

[8] A semiconductor manufacturing apparatus, a pharmaceutical delivery apparatus, a chemical manufacturing apparatus, or a chemical delivery apparatus, comprising the fluid treatment apparatus according to the above 7.

[9] A method for producing a welding material according to any one of the above 1 to 6, comprising: and a step of compression molding the fluororesin composition in which the carbon nanotubes are dispersed in the fluororesin.

[10] A method for producing a welding material according to any one of the above 1 to 6, comprising: a step of preparing a fluororesin composition in which carbon nanotubes are dispersed in a fluororesin selected from PTFE and modified PTFE; a step of putting the fluororesin composition into a mold, and compressing the fluororesin composition under pressure to produce a preform; a step of firing the preform at a temperature not lower than the melting point of the fluororesin composition to produce a molded body; and processing the molded body to produce a fusion material.

[11] A method for producing a welding material according to any one of the above 1 to 6, comprising: a step of preparing a fluororesin composition in which carbon nanotubes are dispersed in a fluororesin other than PTFE and modified PTFE; heating the fluororesin composition, and then compressing the heated fluororesin composition under pressure to obtain a molded article; and processing the molded body to obtain a fusion material.

Effects of the invention

The welding material according to the embodiment of the present invention has excellent antistatic performance, can prevent elution of impurities (metal ions, organic substances, and the like), and exhibits excellent welding strength. Therefore, the present invention can be applied to a fluid processing apparatus, for example, a semiconductor manufacturing apparatus, a drug manufacturing apparatus, a chemical manufacturing apparatus, or the like, a part through which a fluid flows, a nozzle, a head, a spray nozzle, a spin rinse nozzle, a liquid discharge unit, a piping member, a liquid (or chemical liquid) transport pipe, a liquid transport joint, a lining pipe, a lining tank, or the like.

Drawings

Fig. 1 shows an example of the joining of fluororesin members (a rectangular parallelepiped member and a cylindrical member).

Fig. 2 shows an example of the joining of fluororesin members (a rectangular parallelepiped member and a rectangular parallelepiped member).

Fig. 3 shows the joining of the liner ends provided in the liquid-filled tank.

Fig. 4 shows a measurement sample for measuring the welding strength of the welding material.

Fig. 5 schematically shows a method for measuring the welding strength of the welding material.

Detailed Description

The present invention provides a novel welding material which is formed by a fluororesin composition dispersed with carbon nano tubes in fluororesin, wherein the fluororesin composition contains 0.01-2.0 mass% of the carbon nano tubes.

The welding material according to the embodiment of the present invention is formed of a fluororesin composition in which carbon nanotubes are dispersed in a fluororesin.

In the present specification, the fluororesin composition contains a fluororesin and carbon nanotubes, and may contain other components as needed, and is not particularly limited as long as the objective welding material of the present invention can be obtained.

In the present specification, the "fluororesin" is a resin generally understood as a fluororesin, and is not particularly limited as long as the objective welding material of the present invention can be obtained.

Examples of such a fluororesin include at least 1 selected from Polytetrafluoroethylene (PTFE), modified polytetrafluoroethylene (modified PTFE), tetrafluoroethylene/perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene/hexafluoropropylene copolymer (FEP), ethylene/tetrafluoroethylene copolymer (ETFE), ethylene/chlorotrifluoroethylene copolymer (ECTFE), Polychlorotrifluoroethylene (PCTFE), polyvinylidene fluoride (PVDF), and polyvinyl fluoride (PVF).

As the fluororesin, Polytetrafluoroethylene (PTFE), modified polytetrafluoroethylene (modified PTFE), tetrafluoroethylene/perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene/hexafluoropropylene copolymer (FEP), ethylene/tetrafluoroethylene copolymer (ETFE), Polychlorotrifluoroethylene (PCTFE), polyvinylidene fluoride (PVDF) are preferable, and modified polytetrafluoroethylene (modified PTFE), tetrafluoroethylene/perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene/hexafluoropropylene copolymer (FEP), Polychlorotrifluoroethylene (PCTFE) are more preferable.

Commercially available fluororesins can be used. For example, as Polytetrafluoroethylene (PTFE), there can be exemplified M-12 (trade name), M-11 (trade name) and Polyflon PTFE-M (trade name) manufactured by Daiki industries, Ltd.;

examples of the modified polytetrafluoroethylene (modified PTFE) include M-111 (trade name), M-111 (trade name) and Polyflon PTFE-M (trade name) manufactured by Daiki Industrial Co., Ltd;

examples of Polychlorotrifluoroethylene (PCTFE) include M-300PL (trade name), M-300H (trade name) and Neoflon PCTFE (trade name) manufactured by Daiki industries, Ltd;

examples of tetrafluoroethylene/perfluoroalkyl vinyl ether (PFA) include AP-230 (trade name), AP-210 (trade name), and Neoflon PFA (trade name), which are available from Dajin industries, Inc., and Fluon PFA (trade name), which is available from Asahi glass company, Inc.

The fluorine resins may be used alone or in combination.

In the embodiment of the present invention, the fluororesin of the fluororesin composition has a particulate form, preferably has an average particle size of 500 μm or less, more preferably 8 to 250 μm, still more preferably 10 to 50 μm, and particularly preferably 10 to 25 μm.

When the fluororesin of the fluororesin composition has an average particle size of 500 μm or less, the fluororesin and the carbon nanotubes can be more uniformly mixed, and therefore the conductivity is further improved.

In the present specification, the average particle diameter of the particles means an average particle diameter D obtained by measuring a particle size distribution using a laser diffraction scattering particle size distribution apparatus ("MT 3300 II" manufactured by japanese national institute of technology)₅₀(means a median diameter of particle diameters at which 50% of the particle diameters are integrated in the particle size distribution obtained by the laser diffraction scattering method).

In the present specification, "carbon nanotube" is a substance generally understood as a carbon nanotube, and is not particularly limited as long as the fusion material targeted by the present invention can be obtained.

Examples of such carbon nanotubes (also referred to as "CNTs") include single-layer CNTs, multi-layer CNTs, and 2-layer CNTs. As the carbon nanotube, commercially available products, for example, CNT-uni (trade name) series produced by Dayang Nippon Co., Ltd, can be used.

CNTs can be used alone or in combination.

In the embodiment of the present invention, the carbon nanotubes preferably have an average length of 50 μm or more, more preferably 70 to 250 μm, further preferably 100 to 200 μm, and particularly preferably 150 to 200 μm.

CNTs having an average length of 50 μm or more are preferable because the conductive paths are easily connected to each other and the conductivity is further improved.

In the present specification, the average length (or average fiber length) of the CNTs refers to an average length obtained from an image captured by SEM, as described in detail in examples. That is, a part of the flux was heated to 300 to 600 ℃ and incinerated to obtain a residue (sample for SEM imaging). An SEM image of the residue was taken. The length of each carbon nanotube contained in the SEM image is obtained by image processing. The average value of the lengths obtained by this image processing is obtained by calculation, and this average value is referred to as the average length of the CNT.

In an embodiment of the present invention, the fluororesin composition contains 0.01 to 2.0% by mass, preferably 0.04 to 1.5% by mass, more preferably 0.05 to 1.0% by mass, and particularly preferably 0.05 to 0.5% by mass of carbon nanotubes based on 100% by mass of the fluororesin composition.

The fluororesin composition containing 0.05 to 0.5 mass% of carbon nanotubes is preferable because it is a sufficient amount for forming a conductive path, and thus the conductivity is further improved.

The fusion material of the embodiment of the present invention preferably has 1 × 10^-1～1×10⁸A volume resistivity of 1 Ω · cm, more preferably 1 × 10⁰～1×10⁵The volume resistivity of Ω · cm is particularly preferably 1 × 10¹～1×10³Volume resistivity of Ω · cm.

The measurement of the volume resistivity is described in examples.

In the fusion-spliced material according to the embodiment of the present invention, the antifouling property obtained by evaluating the method described in the examples of the present specification is preferably less than 5ppb in the detected amount of Al, Cr, Cu, Fe, Ni, and Zn, more preferably less than 5ppb in the detected amount of Al, Cr, Cu, Fe, Ni, Zn, Ca, K, and Na, and particularly preferably less than 5ppb in the eluted amount of all metals.

In addition, the elution amount of total organic carbon is preferably less than 50ppb, more preferably less than 40ppb, further preferably less than 30 ppb.

The welding material of the embodiment of the present invention may have various shapes and sizes according to the use thereof, and the shape and size thereof are not particularly limited as long as the welding material targeted by the present invention can be obtained.

The shape of the welding material may be appropriately selected, and for example, a rod, a pellet, a sphere, a block, a line, a plate, or the like may be appropriately selected in accordance with the target welding site (bonding site).

The size of the welding material can be appropriately selected in consideration of the welding portion to be welded and the shape of the welding material corresponding thereto.

The shape of the welding material is preferably a rod having a circular or triangular cross section with a diameter of 2 to 5mm, for example. The fluororesin of the welding material preferably contains PFA.

The fusion material according to the embodiment of the present invention can be produced by any method as long as the fusion material targeted by the present invention can be obtained.

The welding material according to the embodiment of the present invention is preferably produced by a production method including a step of compression molding a fluororesin composition in which carbon nanotubes are dispersed in a fluororesin.

The method for producing the welding material according to the embodiment of the present invention may be partially different in the compression molding method depending on the fluororesin contained therein. The manufacturing method of the welding material with respect to PTFE and modified PTFE and the manufacturing method of the welding material with respect to other fluororesins (e.g., PFA, FEP, ETFE, ECTFE, PCTFE, PVDF, and PVF) may be partially different.

A method for producing a welded material of PTFE and modified PTFE comprises: a step of preparing a fluororesin composition in which carbon nanotubes are dispersed in a fluororesin (preferably a particulate fluororesin); a step of compressing the fluororesin composition (after performing appropriate pretreatment (predrying, granulation, etc.) as required) in a mold under pressure of preferably 0.1 to 100MPa, more preferably 1 to 80MPa, and still more preferably 5 to 50MPa to produce a preform; a step of firing the preform at a temperature of the melting point of the fluororesin composition or higher (preferably 345 to 400 ℃, more preferably 360 to 390 ℃) for preferably 2 hours or longer to produce a molded article; and a step of processing (preferably cutting) the molded body to produce a weld material.

The manufacturing method of the welding material of the fluorine resin (such as PFA, FEP, ETFE, ECTFE, PCTFE, PVDF and PVF) except PTFE and modified PTFE comprises the following steps: a step of preparing a fluororesin composition in which carbon nanotubes are dispersed in a fluororesin (preferably a particulate fluororesin); a step of putting the fluororesin composition into a mold, and, after a suitable pretreatment (such as predrying) is performed as required, heating the fluororesin composition at a temperature of, for example, 150 to 400 ℃ for 1 to 5 hours, and then compressing the fluororesin composition at a pressure of, for example, 0.1 to 100MPa (preferably 1 to 80MPa, more preferably 5 to 50MPa) to obtain a molded article; and a step of processing (preferably cutting) the molded body to obtain a fusion material.

The welding material according to the embodiment of the present invention can be used for bonding fluororesins (herein, the fluororesin includes a fluororesin member and a fluororesin molded body), and is preferably used for bonding fluororesins to each other.

The present invention provides a welding material used for a joint part of fluororesin (the fluororesin includes a fluororesin component and a fluororesin molding body), preferably used for a joint part of the fluororesin.

The position of use of the welding material of the present invention is not particularly limited as long as it can be used, and for example, a portion to which fluororesin is bonded and a fluid is in contact with the bonded portion is suitably used. More specifically, examples of such a portion include a nozzle, a head, a spray nozzle, a rotary cleaning nozzle, a liquid discharge portion, a piping member, a liquid transport pipe, a liquid transport joint, a lining pipe, and a lining tank.

The form of the bonding portion is not particularly limited as long as the fusion-bonding material according to the embodiment of the present invention can be used. Examples of the bonding site include surface-to-surface bonding, surface-to-line bonding, surface-to-dot bonding, line-to-line bonding, line-to-dot bonding, and dot-to-dot bonding.

The fluororesin molded article and the fluororesin member are molded articles and members produced using a fluororesin, and are not particularly limited as long as they can be bonded using the welding material according to the embodiment of the present invention, and examples thereof include sheets, films, plates, rods, blocks, tubes, pipes (pipe), tubes (tube), and processed articles produced by the following methods (for example, cutting, spin-coating, stretching, blow molding, injection molding, vacuum injection molding, 3D printing, three-dimensional molding, and the like).

The present invention provides a fluid processing apparatus including the welding material according to the embodiment of the present invention at a welding portion. In the present specification, the term "treatment" is not particularly limited as long as it relates to a treatment of a fluid, and examples thereof include storage, heating, pressurization, cooling, stirring, mixing, filtration, extraction, separation, a combination thereof, and the like.

The present invention also provides various apparatuses including such a fluid processing apparatus, for example, a semiconductor manufacturing apparatus, a pharmaceutical delivery apparatus, a chemical manufacturing apparatus, a chemical delivery apparatus, and the like.

A welding material according to an embodiment of the present invention will be described with reference to the drawings.

Fig. 1 and 2 show examples of bonding of fluororesin members to each other.

Fig. 1 schematically shows a combination of a rectangular parallelepiped (or block) shaped fluororesin member and a cylindrical fluororesin member. The bonding portion is (fusion) welded, and in this case, the welding material according to the embodiment of the present invention may be used. The bonding surface of fig. 1 is annular, and a welding material may be used for the annular bonding surface, the outer peripheral portion and/or the inner peripheral portion of the annular bonding surface between the members. A fusion material may be used to plug the gaps, etc., that may occur at the bonding sites.

When both the rectangular parallelepiped fluororesin member and the cylindrical fluororesin member do not have conductivity, the welding material according to the embodiment of the present invention is grounded, and static electricity prevention, static electricity removal, and the like of a liquid or the like contacting the welded portion can be performed. When either one of the rectangular parallelepiped fluororesin member and the cylindrical fluororesin member has conductivity, either one of the rectangular parallelepiped fluororesin member and the cylindrical fluororesin member may be grounded. The fluororesin molded body having conductivity is preferably formed of a fluororesin composition in which carbon nanotubes are dispersed in a fluororesin.

Fig. 2 schematically shows the combination of a rectangular parallelepiped fluororesin member and a rectangular parallelepiped fluororesin member. The bonding portion is (fusion) welded, and in this case, the welding material according to the embodiment of the present invention may be used. The bonding surface of fig. 2 has a rectangular shape, and a welding material may be used for the rectangular bonding surface and/or the outer peripheral portion of the rectangular bonding surface between the members. A fusion material may be used to plug the gaps, etc., that may occur at the bonding sites.

When both the rectangular parallelepiped fluororesin member and the rectangular parallelepiped fluororesin member do not have conductivity, the welding material according to the embodiment of the present invention is grounded, and static electricity prevention, static electricity removal, and the like of a liquid or the like contacting a welded portion can be performed. When either one of the rectangular parallelepiped fluororesin member and the rectangular parallelepiped fluororesin member is conductive, the conductive fluororesin member may be grounded.

In addition, as the bonding portion, surface-to-surface bonding is exemplified, but as long as the welding material according to the embodiment of the present invention can be used, the form of the bonding portion is not particularly limited. Examples of the bonding site include surface-to-surface bonding, surface-to-line bonding, surface-to-dot bonding, line-to-line bonding, line-to-dot bonding, and dot-to-dot bonding.

In fig. 3, a liquid-filled tank is illustrated as a more specific device.

Fig. 3 schematically shows a can having a fluororesin liner sheet provided on the inner surface thereof. The tank includes an outer tank 1, an inner liner 2 provided on an inner surface of the outer tank 1, a liquid inlet pipe 3 for introducing a liquid into the tank, and a liquid outlet pipe 4 for taking out the liquid to the outside of the tank, and the tank can store a liquid (not shown). The inner liner is preferably formed of a fluororesin composition in which carbon nanotubes are dispersed in a fluororesin, and antistatic properties and antifouling properties can be obtained with respect to the liquid in the tank by the inner liner.

The inner liner 2 provided on the inner surface of the outer vessel 1 is coupled between opposite ends thereof. That is, a joint (a) exists between both end portions, and a gap may be generated (see the right drawing of fig. 3). The gap can be closed by the welding material according to the embodiment of the present invention, and leakage and the like can be prevented, and antistatic and contamination by metal and the like can be prevented.