WO2004052627A1

WO2004052627A1 - Covering material for welding, jointed structures, welding procedure, welded articles and composite structures

Info

Publication number: WO2004052627A1
Application number: PCT/JP2003/014871
Authority: WO
Inventors: Tatsuro Uchida; Kenji Kawasaki; Kazuo Ishiwari
Original assignee: Daikin Industries, Ltd.
Priority date: 2002-12-12
Filing date: 2003-11-21
Publication date: 2004-06-24
Also published as: AU2003284615A1; JP2004189939A; TW200410874A

Abstract

The invention provides a covering material for welding which can inhibit the permeation of chemical liquid through the joint of sheets, is excellent in weld reliability, and does not cause leakage; and a welding procedure which comprises applying the covering material on base materials. The covering material for welding consists of a modified polytetrafluoroethylene resin (A) characterized by being composed of tetrafluoroethylene and a minor monomer, and is used in welding base materials made of a polytetrafluoroethylene resin (B) for the purpose of covering the joint between the base materials. Namely, the joint between the base materials can be covered by placing the covering material over the joint and welding the covering material to the base materials.

Description

Specification

Welding cladding materials, bonded structures, welding methods, welding products and composite articles

The present invention relates to a welding covering material, a joint structure, a welding method, a welded product, and a composite article. Background art

Articles requiring corrosion resistance, such as metal cans and piping materials, are lined with a resin that has chemical resistance and solvent resistance. Conventionally, lining has been performed not by coating but by sheet lining, because low chemical permeability is required. In sheet lining, sheet materials are used to cover the inner walls of can bodies, piping materials, and the like.

Fluororesin is generally used as a sheet material, but among them, polytetrafluoroethylene (PTFE) resin has low dust due to the extremely low metal content in the resin itself and little metal elution. It is suitably used as a sheet material for semiconductor-related containers, which have high requirements for properties.

Sea lining requires welding seams in the sheet. As a method of welding, a method was considered in which sheets were overlapped at a seam portion and the overlapped portions were heat-sealed from above and below, but sheets made of tetrafluoroethylene homopolymer [TFE homopolymer] were used. Then, there was a problem that adhesion was difficult. In order to adhere the sheets, a method using a modified polytetrafluoroethylene [modified PTFE] resin for at least one of the superposed sheets (see, for example, Japanese Patent Publication No. 56-36064) is used to melt the gap between the PTFE sheets. As a method of adhesion, a method of interposing a tetrafluoroethylene Z perfluoro (alkylbier) ether copolymer [PFA] film between PTFE sheets and fusing (for example, JP-A-52-63274 and See JP-A-52-63275.) Has been proposed.

However, all of the above methods are heat fusion methods, and the entire fusion portion is added. Heating was required, which caused an increase in welding time and a decrease in productivity. Also, the lining of the can body and the piping material had a problem in that one side of the sheet was in contact with the inner wall of the can body and the piping material, and it was impractical to apply pressure from both sides of the sheet. As a method of bonding the sheet, both ends of the sheet to be a seam are cut and made into a groove, butted, a welding rod made of PFA is embedded in the groove, and the sheet joint is obtained. In addition, a method has been devised for thermally welding a welding cladding material such as a reinforcement rifon made of PFA.

A method using a PTFE polymer as a sheet is known as a method of using a welding covering material composed of PFA.However, in order to obtain stable adhesiveness, a method is required in which a sheet joining portion and a welding covering material are previously provided. A method in which a primer made of PFA is interposed in the welded portion (for example, JP-A-59-120417, JP-A-57-163524, JP-A-57-142246, and JP-A-59-33331. No., etc.) have been proposed and are still in progress.

However, in the method using a primer, it is difficult to control the coating thickness, there is a problem that welding reliability is reduced due to uneven coating, and a surfactant is used to stabilize the primer. Exposure to highly oxidizing chemicals, such as those used in industry, has caused defects in which surfactants cause dust.

In the method using a PFA welding coating, pressure is applied to weld the sheet joint and the welding coating, but at this time, the molten welding coating is applied from the boundary between the welding coating and the sheet. There was a problem of forming a leaked portion where the material protruded. Since the leaked part is not pressurized during the welding process, there is a problem that cracks are generated due to crystallization shrinkage during cooling after welding. In particular, during lining of cans and piping materials in the semiconductor industry and the like, there was a problem that foreign matter attached to the leaked portion became dust.

The leak at the boundary between the sheet and the welding cladding material must be cut off, but at this time the sheet may be damaged. If the sheet is scratched, the boundary is hardly stretched when concentrated stress is applied, and voids due to partial elongation at the weld boundary are likely to occur when stretching such as flange processing is performed. There was a problem that transmission occurred. In recent years, resin base materials with higher specific gravity than conventional ones have been developed, and although some improvement has been seen in the reduction of chemical liquid permeability, high cleanliness has been achieved due to the ultra-integrated and high-density semiconductor circuits. In order to avoid corrosion of the inner walls of can bodies and piping materials and elution of metals from the lining material, a higher degree of low chemical permeability is required. Summary of the Invention

The present invention has been made in view of the above circumstances, and provides a weld coating material that has low chemical liquid permeation at a sheet joint, has excellent welding reliability, and does not generate cracks or leaks. An object of the present invention is to provide a welding method for coating.

The present invention relates to a welding coating material comprising a modified polytetrafluoroethylene resin (A), wherein the welding coating material is provided on a joint of a resin base material comprising a polytetrafluoroethylene resin (B). The modified polytetrafluoroethylene resin (A) is used to cover the joint of the resin base material by welding by placing the resin on A weld cladding material characterized by the following.

The present invention provides a joining structure comprising a joining portion of a resin base material made of a polytetrafluoroethylene resin (B) and the above-mentioned welding coating material, wherein the above-mentioned welding coating The modified polytetrafluoroethylene resin (A) consists of tetrafluoroethylene and a trace amount of monomer. It is a joining structure characterized by the following.

The present invention is a welded product characterized by having the above-mentioned joint structure. The present invention provides a welding method comprising placing the above-mentioned welding coating material on a joint portion of a resin base material made of polytetrafluoroethylene resin (B) and welding the welding coating material. Is a welding method characterized by comprising a polytetrafluoroethylene resin (A). Detailed Disclosure of the Invention

Hereinafter, the present invention will be described in detail. The weld coating material of the present invention comprises a modified polytetrafluoroethylene resin (A).

The modified polytetrafluoroethylene resin (A) comprises tetrafluoroethylene [TFE] and a trace amount of monomer. That is, the modified polytetrafluoroethylene resin (A) is a resin composed of a copolymer composed of TFE and a trace amount of monomer.

The trace monomer is used for the trace copolymer to such an extent that the obtained copolymer does not impart melt flowability.

The above-mentioned trace monomer is not particularly limited as long as it is capable of copolymerizing with TFE and does not impart melt fluidity to the obtained copolymer.For example, hexafureo-mouth propylene (HFP And the like. Perfluorofluorin such as ethylene, etc .; chlorofluoroolefin such as ethylene, trifluorene, etc .; hydrogen-containing fluorofluorin such as ethylene / trifluoroethylene; perfluorobutyl ether.

The perfluorobutyl ether is not particularly limited. For example, the following general formula

CF ₂ = CF—OR f

(In the formula, R f represents a perfluoro organic group.). In the present specification, the above “perfluoro organic group” means an organic group in which all hydrogen atoms bonded to carbon atoms are replaced by fluorine atoms. The perfluoro organic group may have ether oxygen. Examples of the perfluorobutyl ether include, for example, a perfluoro (alkylbutyl) ether in which R f represents a perfluoroalkyl group having 1 to 10 carbon atoms in the above general formula [: PAVE] Is mentioned. The above-mentioned perfluoroalkyl group preferably has 1 to 6 carbon atoms.

Examples of the perfluoroalkyl group in the above PAVE include a perfluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluorobutyl group, a perfluoropentyl group, a perfluorohexyl group and the like. However, a perfluoropropyl group is preferred.

Preferably, the trace monomer is PAVE and / or HFP. The modified polytetrafluoroethylene resin (A) is a copolymer in which the trace monomer unit derived from the trace monomer is composed of TFE and the trace monomer in a range of 0.05 to 0.5. It is preferably 7% by mass. If the amount is less than 0.05% by mass, the obtained welding covering material may have poor adhesion to a resin base material described later. If it exceeds 0.7% by mass, the specific gravity of the welded coating described later tends to decrease, and the chemical permeability may increase. In the present specification, the above-mentioned trace monomer unit is a part on the polymer molecular structure of the modified polytetrafluoroethylene resin (A), and means a part derived from the trace monomer.

As the modified polytetrafluoroethylene resin (A), for example, one or more copolymers having different molecular weight distributions, copolymer compositions, and the like may be used.

The number average molecular weight of the copolymer of the modified polytetrafluoroethylene resin (A) is such that the amount of the trace monomer unit is within the above-mentioned range, and the melt viscosity is in the range described later, namely, 1 × 1 0 ⁸ defined as to 1 5 X 1 0 ⁸ those in P a · s in the range of, usually, it is preferably in the range of 2 00000-2 0 0 0 250,000. When the number average molecular weight is within the above range, the mechanical strength of the welded coating portion in the obtained joint structure described later will be good. A more preferred lower limit is 1,800,000, and a still more preferred lower limit is 6,300,000. The polymerization method for obtaining the modified polytetrafluoroethylene resin (A) is not particularly limited, and examples thereof include conventionally known polymerization methods such as emulsion polymerization and suspension polymerization.

The above-mentioned welding coating material is obtained by subjecting the modified polytetrafluoroethylene resin (A) after polymerization to powder obtained by subjecting the modified polytetrafluoroethylene resin (A) to pulverization, granulation, or the like, if desired, by ram extrusion, paste extrusion, compression, or the like. It may be obtained by molding by a conventionally known molding method such as molding, or may be obtained by cutting a molded body.

The weld dressing, it preferably has a melt viscosity are those wherein ^{l X 1 0 8 ~ 1 5} X 1 0 8 P a ■ s. When the melt viscosity is within the above range, although a slight deformation occurs during welding and pressurization, formation of a leak portion described later can be suppressed. In order to obtain a weld coating material having a melt viscosity within the above range, usually, a modified polytetrafluoroethylene resin (A) having a melt viscosity within the above range is used. The melt viscosity η was measured using a dynamic viscoelasticity measuring device (trade name: PDS-II, manufactured by Rheometrics).

The welding cladding material of the present invention is for covering the joint portion of the resin base material by placing on the joint portion of the resin base material and performing welding.

The above-mentioned welding covering material has a shape capable of covering the joint portion of the resin base material described later, and may have a thickness sufficient to reduce the permeability of the chemical solution. It has a shape such as a shape and a band.

In the present specification, the above-mentioned resin base material means a resin molded article to be covered with the above-mentioned welding covering material placed on a joint. The resin base material has a size suitable for being partially or entirely covered with the welding coating material.However, the thickness, size, etc., must be larger than the welding coating material. There is no limitation. The shape of the resin base material is not particularly limited, and examples thereof include a block shape and a sheet shape. Among them, a sheet shape is preferable, and a lining sheet base material is more preferable.

The lining sheet base material is a sheet-like resin base material that can be used as a lining material for coating a base material. The above-mentioned lining material covers the above-mentioned base material in sheet lining, thereby imparting corrosion resistance, improving mechanical strength, etc., protecting the above-mentioned base material, imparting non-adhesiveness, smoothing the surface, etc. And a substance exhibiting an action of improving the surface properties of the above-mentioned base material, an action of improving the appearance of the above-mentioned base material, and the like.

The base material is not particularly limited, but is generally preferable or required to exhibit the function of the lining material. Examples of the material include stainless steel, copper, aluminum, bronze, zinc, brass, and titanium. Metal; glass and the like. The Rayunda sheet base material may be used as it is without cutting the resin molded body, but is generally manufactured by cutting from a large block-shaped resin molded body. The lining sheet base material may be formed by applying an appropriate surface treatment or laminating a heat-resistant nonwoven fabric such as a glass cloth or a heat-resistant woven fabric in order to adhere to the base material.

The resin matrix is made of a polytetrafluoroethylene resin (Β). The polytetrafluoroethylene resin (B) may be a tetrafluoroethylene homopolymer (TFE homopolymer) resin obtained by polymerizing only TFE, or may be TFE and the above-mentioned trace monomer. The modified polytetrafluoroethylene resin (B 1), which has a body and strength, may be used. However, a primer is not required when welding the above-mentioned welding coating material composed of the modified polytetrafluoroethylene resin (A). In view of the above, it is preferable that the resin is a modified polytetrafluoroethylene resin (B 1). The modified polytetrafluoroethylene resin (B 1) is a modified polytetrafluoroethylene resin similarly to the modified polytetrafluoroethylene resin (A) described above, but is used in the resin base material. It is conceptually different from the above-mentioned modified polytetrafluoroethylene resin (A) used for the above-mentioned weld coating material. The copolymer of the modified polytetrafluoroethylene resin (B 1) is composed of the copolymer of the modified polytetrafluoroethylene resin (A) and the kind of the trace monomer, the ratio of the trace monomer unit, and the molecular weight distribution. And the like may be the same or different, but are preferably substantially the same in terms of adhesiveness.

The resin base material may be composed of additives and the like in addition to the resin component. The resin component is preferably the polytetrafluoroethylene resin (B), and may be only the polytetrafluoroethylene resin (B).

In the present specification, the “joined portion of the resin base material” means a portion of the resin base material formed by joining the ends.

In the present specification, the term “joining” means at least sticking or joining such that they cannot be separated without mechanical cutting. The term “joining” generally means that the resin base material and a later-described welding auxiliary material that is used as desired are adhered or fused by fusion.

The joints of the above resin base materials should be brought into direct contact with the resin base materials having the same or different shapes, sizes, etc., by abutting each other, and heated to a temperature above the melting point of the polytetrafluoroethylene resin (B) under pressure. In this case, the resin base materials may be joined together, or the resin base materials having the same or different shapes, sizes, etc. may be interposed with a welding rod or primer, which is a welding auxiliary material described later, interposed therebetween. The resin base materials may be indirectly bonded to each other. The joint portion of the resin base material may be formed by abutting two resin base materials with a groove and filling a recess formed by this with a welding rod. The welding rod will be described later. The joint portion of the resin base material may be, for example, a structure in which both ends of a sheet-shaped resin base material such as a single liner sheet base material are joined, or two resin base materials are joined. It may be something. The joint portion of the resin base material is usually a part of the resin base material. However, since the resin base material is to be covered with the welding coating material as described above, the resin base material is When the size is almost the same as the welding cladding material, it may refer to the entire resin base material.

In the present specification, the “placing on the joining portion” means placing the welding covering material on the joining portion of the resin base material. When the resin base material is made of the TFE homopolymer resin, it is necessary to mediate a primer described below between the resin base material and the weld coating material. When the resin is made of a tetrafluoroethylene resin (B1), the primer does not need to be interposed because the compatibility with the modified polytetrafluoroethylene resin (A) in the weld coating material is excellent.

In the present specification, the above-mentioned “welding” means that the joint portion of the resin base material and the welding covering material are fused.

In the present specification, the term “welding” refers to fusing the joint portion of the resin base material and the weld coating material, whereas the term “joining” at the joint portion of the resin base material is as described above. In addition, the two are distinguished from each other in that a resin base material having the same or different shape or size is fused. The joined structure of the present invention comprises a welded coating made of the modified polytetrafluoroethylene resin (A) and a joined part of a resin base material made of the polytetrafluoroethylene resin (B). And is obtained by placing the welding covering material on the joint portion of the resin base material and performing welding.

The joint structure includes a weld coating portion derived from the welding coating material and a resin base material portion described below derived from the resin base material.

In the present specification, the term "weld coating portion" means a portion derived from a welding coating material after welding in the joint structure. The above welded coating It has not undergone welding because the crystallinity before heating may have changed due to heating during welding, and as a result, the specific gravity may have changed. This is a different concept from the welding cladding material.

In the present specification, the “resin base material portion” means a portion derived from the resin base material after performing the welding, including a portion affected by heating during welding in the joint structure. I do. As described above, the resin base material portion includes a portion affected by heating during welding, and thus includes at least a portion existing under the weld coating portion, and the resin base material after welding is performed. Since it is a part derived from the material, the vertical portion sandwiched between the contact surface and the back surface of the resin coating material to be placed in the horizontal portion of the resin base material that will be present below the weld coating portion It is derived from the direction part. The above-mentioned resin base material portion has been subjected to welding, and may have a degree of crystallinity or the like before heating due to heating during welding, and may have a specific gravity changed as a result. In a good point, it is a different concept from a resin base material that has not been welded.

As described above, the modified polytetrafluoroethylene resin (A) is a copolymer in which the above-mentioned trace monomer unit derived from the trace monomer is composed of the TFE and the ^: monomer. 0 5 to 0.7 weight it is preferable ^_0/0.

The bonded structure of the present invention can be used in applications where a high degree of low chemical liquid permeability is required, in which the modified polytetrafluoroethylene resin (A) is used. It is preferable that the content of the copolymer is from 0.05 to 0.5% by mass, and that the specific gravity of the weld coating portion is from 2.145 to 2.210.

In the modified polytetrafluoroethylene resin (A), when the above-mentioned trace monomer unit is 0.05 to 0.5% by mass of the copolymer composed of TFE and the trace monomer, weld coating The specific gravity of the welded portion can be increased, and the specific gravity of the welded coating is reduced to 2.14.5-2.210. When the specific gravity is within the above range, the bonded structure of the present invention has a high low chemical solution permeability.

The specific gravity of the above-mentioned welded coating is the value obtained by cutting out a sample in accordance with JIS K 7 13 7-2 and measuring in accordance with the JIS Κ 7 11 2 — method (underwater replacement method). is there. However, the specific gravity is such that the resin base material portion is made of heat-resistant non-woven fabric such as glass cloth or the like. When the heat-resistant nonwoven fabric or heat-resistant woven fabric is laminated, the measurement is performed after the heat-resistant nonwoven fabric or the heat-resistant woven fabric is peeled off.

Upon obtaining a joined structure of the present invention, it is preferable that the welding melt viscosity of the coating material (a) is a ^{1 X 1 0 8 ~1 5 X} 1 0 8 P a · s as described above (condition ①), Further, it is preferable that the above-mentioned melt viscosity (a) is less than or equal to the melt viscosity (b) of the resin base material (condition 1).

In the joint structure of the present invention, provided that the welding coating used is made of the modified polytetrafluoroethylene resin (A) and the melt viscosity of the welding coating used satisfies the above conditions (1) and (2), It can have excellent welding reliability. The bonded structure of the present invention has high reliability and high crystallinity of the above-mentioned welded coating portion and resin base material in order to have welding reliability and further ensure low chemical solution permeability. It is preferred that

With the above welding reliability, the welding coating material and the resin base material are fused together on the entire surface where they come into contact, and when the welding reliability is lost, the above chemical solution, gas, etc., in the presence of chemicals, highly reactive gases, etc. May penetrate through a gap between the weld coating and the resin base material. It is generally considered that the melt viscosity does not change before and after welding. Therefore, the above condition (1), or the above condition (1) and (2), that the condition (1) was satisfied before welding is that after welding. The joint structure can be confirmed by measuring the melt viscosity of the weld coating portion and the melt viscosity of the resin base material portion. Junction structure of the present invention,従Tsu Te, lay like those melt viscosity of the welded covering portion is ^{l X 1 0 8 ~1 5 X} 1 0 8 P a · s, the melt viscosity of the weld covering portion, It is more preferable that the value be within the above range and be equal to or less than the melt viscosity of the resin base material.

As described above, the polytetrafluoroethylene resin (B) in the resin base material used to obtain the joined structure of the present invention is a modified polytetrafluoroethylene resin (TFE and a trace amount of monomer) B 1) is preferred. When the modified polytetrafluoroethylene resin (B 1) is used as the resin base material, the joint structure of the present invention can be used even if a primer is not used between the resin base material and the weld coating material. It can have good adhesiveness.

In the present specification, the “primer” refers to a portion between the resin base material portion and the weld coating portion. It is a welding aid used to improve the adhesiveness and is a liquid such as disposable when applied.

The primer is made of perfluoro resin (C). The primer is usually a dispurgeon prepared by dispersing particles made of the perfluoro resin (C) in water, an organic medium or a mixture of water and an organic medium, and is dispersion-stabilized with a surfactant or the like. It is.

The perfluoro resin (C) has a melt viscosity of 1 × 10 ⁵ Pa · s or less, and is a resin composed of polymer molecules in which all hydrogen atoms bonded to carbon atoms are replaced by fluorine atoms. Any perfluoroolefin resin is preferred.

In the present specification, the above-mentioned “perfluoroolefin resin” means a resin comprising a polymer obtained by polymerizing at least one kind of perfluoroolefin and, if desired, PAVE.

The perfluoroolefin resin is not particularly limited, and includes, for example, a resin composed of a TFE / HFP copolymer, a resin composed of a TFE / PAVE copolymer, and the like.

It is preferable that the joining structure of the present invention does not use a primer between the resin base material and the above-mentioned welding covering material. If the bonding structure of the present invention does not use a primer, the surfactant contained in the primer may be exposed to a strong oxidizing chemical and carbonized to become a dust generation source. There is no. In the present specification, the phrase "no primer is used between the resin base material and the weld coating material" means that the resin base material is used when the joint structure of the present invention is obtained from the resin base material and the weld coating material. Means that no primer was interposed at any point between the above and the above-mentioned weld coating material.

The use of a primer between “between the resin base material and the weld coating material” means that (i) the primer is coated on the surface of the joint portion of the resin base material on which the weld coating material is to be placed. And (ii) applying the braimer to the surface of the weld coating material that is to be placed on the joint of the resin base material. The joints of the resin base materials are joined with two resin base materials as described below, and the resulting recess is filled with a welding rod. (I) above, a primer is applied to the surface of the two grooved resin base materials that comes into contact with the welding rod to be filled. And applying a primer to the surface of the joint of the resin base material obtained by filling the welding rod, on which the welding coating material is to be placed ((i) 1-2) . The “surface on which the welding cladding material is to be placed” in ((i) 1-2) above is the surface on which the welding cladding material is to be placed on the top of the portion derived from the filled welding rod. It may also include a surface on which the welding rod melted and solidified by filling of the resin base material is not attached and on which the welding coating material is to be placed.

In the joint structure of the present invention, it is preferable that the resin base material before welding is the lining sheet base material described above. If the base material is a lining sheet base, the above-mentioned joined structure is excellent in low chemical liquid permeability as described above, and thus is suitable for a lining material.

The joint structure of the present invention may be one in which no leak portion exists. The above “leakage portion” means a portion formed by protruding from between the welded covering material and the joint portion of the resin base material in the process of pressurizing and melting the welded covering material during welding. The above-mentioned leaked portion is generally called an “extruded portion” or “burr” in that the resin melted by heating protrudes from the intended contour of the resin molded body after heating and melting. Including concepts common to

The above joint structure uses a modified polytetrafluoroethylene resin (A) as the material of the welding coating material, and since it is difficult for a leaked portion to occur even when welding is performed, a conventional leaked structure is used. There is no need to remove the leaked part, which has become indispensable due to the formation of a part. If there is no need to perform the removal treatment, there is no risk of damaging the joined structure, and there is no fear of cracks. The removal process is generally performed by cutting using a tool such as a chisel V-shaped chisel.

The welding method according to the present invention is characterized in that a welding coating material comprising the above-mentioned modified polytetrafluoroethylene resin (A) is placed on a joint of a resin base material comprising the above-mentioned polytetrafluoroethylene resin (B). It consists of mounting and welding.

The above “modified polytetrafluoroethylene resin (A)”, “weld coating material”, “polytetrafluoroethylene resin (B)”, “joining part of resin base material”, “ The “placement” and “welding” are as described above.

In the welding construction method of the present invention, it is preferable that the joint portion of the resin base material is formed by abutting two resin base materials as a groove and filling a recess formed thereby with a welding rod.

The welding rod is a welding auxiliary material mainly used for bonding between the two resin base materials by being interposed between the concave portions, that is, the two resin base materials, and is filled in the four parts. Is a solid prior to the heating at the time of performing. The above-mentioned welding rod not only bonds between the above-mentioned two resin base materials but also contributes to bonding with a welding coating material usually placed on the filled portion. The welding rod may be one which is generally recognized as a welding rod in the field of welding a resin molded article. The welding rod is made of a perfluoro resin (D), and the perfluoro resin (D) preferably has a melt viscosity of 1 × 10 ⁵ Pa a s or less. A more preferred upper limit of the melt viscosity is ^{0. 4X 1 0 5 P a ■} s. The perfluoro resin (D) may be a resin composed of a polymer molecule in which all hydrogen atoms bonded to carbon atoms are substituted with fluorine atoms, and among them, a perfluoro resin resin is preferable. The perfluoro resin is the same as described above for the perfluoro resin (C).

The perfluoroolefin resin is not particularly limited, and examples thereof include a resin composed of a TFEZ PAVE copolymer and a resin composed of a TFE / HFP copolymer.

The perfluoro resin (D) is a resin used for a welding rod, and is conceptually different from the perfluoro resin (C) described above, which is a resin used for a primer between a resin base material and a welding coating material. Are different. The molecular weight distribution of the polymer in the perfluoro resin (D), the type of the monomer, and the like may be the same as or different from the perfluoro resin (C).

Filling of the recesses of the welding rod is performed by applying a pressure of 0.3 to 2.5 MPa at a welding speed of 70 to 20 Omm / min while heating the welding rod to a welding temperature of 460 to 550 ° C. It is preferable to do so. The welding temperature to be used depends on the air volume and welding speed. For example, the upper limit of the above welding temperature of 550 ° C If the welding speed is less than 7 Omm / min, both the polytetrafluoroethylene resin (B) constituting the resin base material and the modified polytetrafluoroethylene resin (A) constituting the welding coating material may decompose together . Therefore, it is preferable to perform welding under the condition that the values of the welding temperature, the welding speed and the pressure are all within the above ranges. In the above-mentioned joint portion of the resin base material, when the above-mentioned welding rod is filled into the concave portion and overflows from the groove, a raised portion (convex portion) is formed after cooling, which hinders welding of the welding coating material. There is. Therefore, it is desirable that the joint portion of the resin base material be obtained by flattening the convex portion with a chisel or the like.

In the welding method according to the present invention, the resin base material is preferably a lining sheet base material. The welding method according to the present invention is preferable in that, when a lining sheet base material is used as the resin base material, the obtained joint structure can realize a high degree of low chemical solution permeability. In the welding method according to the present invention, in the case where the resin base material is a lining sheet base material, in the welding, the contact surface between the joint portion of the resin base material and the weld coating material is in a range of 5200 to 6200C. It is more preferable that the welding is performed by applying a pressure of 0.3 to 2.5 MPa at a welding speed of 30 to 14 O mm while heating so that In the case where the resin base material is made of a resin molded body having the same shape or a different size or the like and is other than the seating base material, for example, a block-shaped molded body, the welding is performed by the resin base material. It is more preferable that the heating is performed so that the contact surface between the joint portion and the weld coating material is at a temperature of 520 to 620 ° C and a pressure of from 0.3 to 5 MPa is applied. .

Cooling after performing the above welding is slow cooling in that the crystallinity of the resin base material and the welded coating in the obtained joint structure can be increased, the specific gravity can be increased, and the chemical permeability can be reduced. And more preferably by air cooling. As described above, in the modified polytetrafluoroethylene resin (A) in the welding coating material used in the welding method of the present invention, the above-mentioned trace monomer unit derived from the trace monomer is TFE and the trace monomer 0 body and force Ranaru copolymer. 0 5 to 0.7 weight it is preferable ^_0/0.

In applications where a high degree of low chemical permeability is required, the above-mentioned trace monomer units derived from the trace monomers of the modified polytetrafluoroethylene resin (A) are combined with TFE and More preferably, the amount is 0.05 to 0.5% by mass of the copolymer comprising the monomer.

The resin base material used in the welding method of the present invention preferably has a specific gravity of 2.175 to 2.200. When the specific gravity is within the above range, the specific gravity of the resin base material after welding is likely to be high, and the chemical permeability is suppressed. In the resin matrix, the trace monomer unit in the copolymer of the modified polytetrafluoroethylene resin (B1) described above exceeds 0.5% by mass of the copolymer composed of TFE and the trace monomer. If it is, the specific gravity tends to be less than 2: 175.

A trace monomer in the modified polytetrafluoroethylene resin (A) used for the welding coating material in the welding construction method of the present invention, and a trace monomer in the modified polytetrafluoroethylene resin ( _{B 1} ) used for the resin base material Is preferably PAVE and / or HFP, as described above.

Welding coating material used in the welding method of the present invention, as described above, it is preferable that ① the melt viscosity (a) is ^{l X 10 8 ~1 5 X 10} 8 P a · s, further, ② the molten It is more preferable that the viscosity (a) is equal to or less than the melt viscosity (b) of the resin base material. If the melt viscosity satisfies the above conditions (1) and (2), welding with reliable welding can be performed.

As described above, it is preferable that the weld coating material be placed on the joint of the resin base material without using a primer on the resin base material. The primer is made of a top predicate Pafuruoro resin (C), the Pafuruoro resin (C) is the melt viscosity is less than ^{1 X 1'0 5 P a · s} .

Since the above welding method uses a welding covering material made of the above-mentioned modified polytetrafluoroethylene resin (A), the welding can be performed without any leakage.

ADVANTAGE OF THE INVENTION By the welding construction method of this invention, the adhesiveness of a weld coating part and a resin base material part can be improved, and the durability and corrosion resistance of the joining structure obtained can be improved. According to the welding construction method of the present invention, it is possible to increase the specific gravity of the weld coating portion and the resin base material. In recent years, a resin base material having a high specific gravity has been developed. It is possible to realize a high low chemical solution permeability that could not be achieved only by increasing the specific gravity. The present invention also includes a joint structure including a joint portion of a resin base material and a welding covering material, the joint structure obtained by the above-described welding method.

A welded product of the present invention has the above-mentioned joint structure. The joint structure is composed of the joint portion of the weld coating material and the resin base material as described above, and the welded product is obtained by welding the resin base material with the weld coating material. Things. The welded article is composed of the joint structure and a portion of the resin base material other than the resin base material that forms the joint structure. As described above, when the entire size of the resin base material is small enough to be affected by heating during welding, as described above, the resin base material itself becomes the resin base material portion that forms the joint structure. The welded product is the joint structure itself.

In the welded article of the present invention, the resin base material is preferably a lining sheet base material. In the present specification, the above-mentioned “welded article in which the resin base material is the lining sheet base material” is referred to as “weld lining material”. In the present specification, the welding line material does not include a base material.

The composite article of the present invention comprises a base material and the above-mentioned welded product.

The base material is an object to be covered with a welding construction product such as the welding lining material, and examples thereof include those described above as being covered by the lining sheet base material.

The size of the composite article is not particularly limited, and may be one used in a plant scale or one used in a laboratory scanle.

The composite article is not particularly limited, and examples thereof include a container, a tank, a tank, a tower, a piping material, a joint, and a chemical reaction member such as a stirring blade. In the composite article, the base material may be in close contact with the welded product, or the base material and the welded product simply come into contact with each other, and can be easily separated. Although it may be good, it is preferable that it adheres.

The composite article is one in which all or a part of one surface of the base material, or all or a part of both surfaces of the base material, is covered with the welded product. In the composite article, when the welded article is made of a lining sheet base material, is it preferable that at least the function of the lining material described above among the surface of the base material is preferable? Alternatively, it is sufficient that the required portion is covered with a lininder sheet base material. The use of the above composite article is not particularly limited. For example, a corrosive or oxidizing chlorine exposing device in which dry chlorine and wet chlorine coexist in the food electrolysis industry, etc .; S 0 ₃ absorption tower; strong oxidizing, hydrogen peroxide in the rubber and FRP and the like which do not withstand long-term use, hypochlorous acid, sulfuric acid, nitric acid, hydrochloric acid, inorganic acid production apparatus such as hydrofluoric acid; semiconductor Examples include a semiconductor manufacturing apparatus for storing or transporting a chemical solution such as hydrofluoric acid used for surface treatment, washing, etc. Among them, an apparatus for use in a semiconductor manufacturing apparatus is preferable.

Among the composite articles of the present invention, examples of the above-mentioned "object used in a semiconductor manufacturing apparatus" include a pipe member in contact with a chemical such as hydrofluoric acid, a joint member of the above pipe member, and a member such as a storage tank. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic top view and a schematic cross-sectional view of a sample for measuring welding strength and elongation. FIG. 2 is a schematic cross-sectional view showing a sampling site of a specific gravity measurement sample. FIG. 3 is a schematic cross-sectional view showing a welding process. 'Fig. 4 is an SEM image of the weld in Reference Example 1. FIG. 5 is a schematic cross-sectional view of a leaked portion and a welded end. Explanation of reference numerals

1 1 Weld coating

1 2 Resin base material

2 1 Weld coating (for specific gravity measurement)

2 2 Welding area 23 groove ω

3 1 Weld coating ;!

32 Resin base material

3 3 hot air

34 Pressurization

35 welding run

5 1 Leakage part

5 2 Weld end Best mode for carrying out the invention

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples. Example 1

The modified PTF-resin powder (melt viscosity of 13 × 10 ⁸ Pa · s, standard specific gravity 2.145) obtained by emulsion polymerization shown in Table 1 was used as a raw material for the weld coating material. To 100 parts by mass of the modified PTFE resin powder, 20 parts by mass of a petroleum-based solvent (trade name: Isopar E, manufactured by Exxon Chemical Co., Ltd.) were added and mixed, followed by paste extrusion. After removing the petroleum-based solvent by drying at 100 ° C to 200 ° C, it was baked at 370 ° C for 1 to 10 minutes to obtain a weld coating. The specific gravity of the obtained weld coating material was 2.149.

A welding rod made of a TFE / PAV E copolymer is blown with hot air of 480 ° C to the groove recess 23 of the resin base material in the schematic cross-sectional view of FIG. 2, and a pressure of 0.3 to 0.5 MPa is applied. Filling was performed at a welding speed of 125 mm / min, and the resin base materials were bonded together. The weld coating material was placed on the obtained joint portion of the resin base material as shown in the schematic cross-sectional view of FIG. 3, and hot air 33 at a temperature of 580 ° C. was blown, and a pressure of 0.3 was obtained at a position shown in 34. Welding was performed at a welding speed of 125 mmZ while applying a pressure of ~ 0.5 MPa to obtain a bonded structure.

The following evaluation was performed on the obtained joined structure.

Stretching strength As shown in the schematic top view and schematic cross-sectional view of FIG. 1, the obtained joint structure has a width of 100 mm and a length of 100 mm consisting of the weld coating portion 11 and the resin base material 12. A sample was cut out. A reference point was set at a distance of 4 O mm on the resin base material of the obtained sample,

Weld joint elongation (%) = [{distance between gauges at maximum elongation (mm)-4 O mm} / 40 mm] X 100

The elongation of the weld was measured based on the above, and the tensile strength was also measured at the same time.

Welding condition

Good weld: Small variation in weld extension and tensile strength, with no unfused spots observed on the cross-section of the bonded structure.

No reliability · "The state where the welded portion has a variation in elongation and tensile strength depending on the sample, and unfused parts are observed on the cross section of the bonded structure.

Welding is impossible. There is almost no elongation and no tensile strength at the weld, and unfused parts are observed on the cross section of the joined structure.

Specific gravity of weld coating and weld periphery

As shown in the schematic cross-sectional view of Fig. 2, the specific gravity measurement is performed from the weld coating 21 and the weld periphery 22 that is a part of the resin base material in accordance with JISK 7 13 7-2. Samples were cut out and their specific gravity was measured in accordance with JISK 7112-II (underwater displacement method).

However, the specific gravity of the glass cloth backing sheet was measured after peeling the glass cloth. Example 2

The modified PTFE resin powder shown in Table 1 was used as a raw material for the weld coating material. The above raw materials are filled in a mold, pressurized at 3 OMPa, a preformed product is obtained, and the preformed product is baked at 37 ° C for 10 hours, then skived, weld coated Wood was obtained. The specific gravity of the obtained weld coating material was 2.195. This welded coating was welded to the resin base material under the welding conditions shown in Table 1, and the obtained jointed structure was evaluated in the same manner as in Example 1. Example 3

The modified PTF E resin powder shown in Table 1 was used as a raw material for the weld coating material. The above raw materials were filled in a mold, pressurized at 3 OMPa, and a preform was obtained.The preform was fired at 370 ° C for 10 hours, skived, and a weld coating material was obtained. . The specific gravity of the obtained weld coating material was 2.152. This welded coating was welded to the resin base material under the welding conditions shown in Table 1, and the obtained jointed structure was evaluated in the same manner as in Example 1. Example 4

The modified PTFE resin powder shown in Table 1 was used as a raw material for the weld coating material. The above raw materials were filled in a mold, pressurized at 3 OMPa, and a preform was obtained.The preform was fired at 370 ° C for 10 hours, skived, and a weld coating material was obtained. . The specific gravity of the obtained weld coating material was 2.139. This welded coating was welded to the resin base material under the welding conditions shown in Table 1, and the obtained jointed structure was evaluated in the same manner as in Example 1. Example 5

The modified PTFE resin powder shown in Table 1 was used as a raw material for the weld coating material. The above raw materials were filled in a mold and pressurized at 30 MPa, and a preform was obtained.The preform was fired at 370 ° C for 10 hours, skived, and a weld coating material was obtained. . The specific gravity of the obtained weld coating material was 2.137. This welded coating was welded to the resin base material under the welding conditions shown in Table 1, and the obtained jointed structure was evaluated in the same manner as in Example 1. Comparative Example 1

Tetrafluoroethylene homopolymer [TFE homopolymer] powder shown in Table 1 was used as a raw material of the coating material. After filling the above-mentioned raw materials in a mold and pressurizing with 3 OMP.a, a preform is obtained, and the preform is fired at 370 ° C for 10 hours. A force eve was applied to obtain a coating material. The specific gravity of the obtained coating material was 2.165. An attempt was made to weld this coating material to the base metal under the welding conditions shown in Table 1, but the welding was not reliable and welding was not possible. Comparative Example 2

The TFE / perfluoro (alkyl) butyl copolymer (PFA) powder shown in Table 1 was used as a raw material for the coating material, and the PFA powder was extruded using a screw extruder to obtain a coating material. Was. The specific gravity of the coating material was 2.140. The welding was performed under the welding conditions shown in Table 1 except that the above-mentioned coating material and the base material were welded at 480 ° C, and the same evaluation as in Example 1 was performed on the obtained joined body. Table 1 shows the properties and welding conditions of the above (welding) coating material, and Tables 2 to 8 show the results of the evaluation of the welding conditions. In Tables 2 to 8, the following resin base materials were used.

Table 2: Sheets obtained from modified polytetrafluoroethylene resin (I) Table 3: Glass cloth backing sheets obtained from modified polytetrafluoroethylene resin (I)

Table 4—Sheets from TFE homopolymer resin (II)

Table 5… Glass cloth backing sheet obtained from TFE homopolymer resin (II)

Table 6: Sheets obtained from modified polytetrafluoroethylene resin (III) Table 7: Glass crossbacking sheets obtained from modified polytetrafluoroethylene resin (III)

t

O

Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Type Modified PTFE (trace amount monomer: PAVE) ma TFE Ho Polymer 1 Standard specific gravity 2,145 2.168 2.168 2.180 2.180 2.15 Melt viscosity 380 ° C (Pa's)

13X10 ⁸ 6.5 X10 ⁸ 6.5 X10 ⁸ 1.0 X10 ⁸ 1.0 X 10 20 1

PAVE-modified amount (mass ^_0/0) 0.08 0.08 0.12 0.40 0.65 0 member

(Welding) Specific gravity of coating material 2.149 2.195 2.152 2.139 2.137 2.16 Welding speed (Arm / min) 10 20 70 90 10 Melting Welding nozzle temperature (V) 580

Pressurizing pressure (MPa) 0.3 to 0.5

Article

Cases Primer application

Strength welding size (mm) 2X14 2.4X14 2X14 2.4X

Resin base material modified polytetrafluoroethylene resin (I) sheet Specific gravity 2.195 Melt viscosity 6.5 X 10 ⁸ Pa's

Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Example 1 Comparative Example 2

Welding condition No reliability Good welding 您 ^? Not good Welding end Welded end なし No leaking part Leakage part Welding part treatment Implemented No contact

Leakage part

Good edge appearance

Crack rating Tensile strength (kgf / cm) 0-35.0 56.0 56.8 58.0 54.0 54.0 54.0 t value Weld elongation (%) 0-40 120 190 170 172 20-65 170

Specific gravity of weld coating 2.150 2.206 2.160 2.145 2.137 2.138 2.138 Specific gravity of weld periphery 2.160 2.185 2.180 2.176 2.175 2.170 2.170

* 2 (SJ

CO

Resin matrix modified polytetrafluoroethylene resin (I) glass backing sheet Specific gravity 2.185 Melt viscosity 6.5 X 10 ⁸ Pa's

Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Example 2 Comparative Example 2

Welding condition No reliability Good welding Good welding not possible Welding good Welded end No leached part Leaked part Leaked part treatment Implemented Not implemented

Leaked part Good appearance of end

crack

> Evaluation Tensile strength (kgf / cm) 0-35.0 56.0 56.8 58.0 54.0 54.0 54.0

Value

Elongation of weld (%) 0 ~ 20 45 43 46 45 20 ~ 45 48 Specific gravity of weld coating 2.150 2.208 2.160 2.145 2.137 2.139 2.139

Specific gravity at weld periphery 2.160 2.180 2.176 2.171 2.170 2.165 2.165

Resin base material TFE homopolymer resin (II) sheet Specific gravity 2.180 Melt viscosity 20 X 10 ^s Pa's

Welding condition Good weldability Not weldable Good weldability Welded end No leaked part 1 Leaked part Leaked part treatment not implemented

Edge appearance good Scratches Crack rating Tensile strength (kgf / cm) 51.0 52.0 55.0 56.0 55.0 53.0 53.0 Value t

Weld elongation (%) 52 50 52 50 55 20-55 60

Specific gravity of weld coating 2.150 2.202 2.160 2.145 2.137 2.138 2.138 Specific gravity of weld periphery 2.160 2.170 2.173 2.170 2.169 2.160 2.160

¾4 t

诣 Base material modified polytetrafluoroethylene resin (ΙΠ) sheet Specific gravity 2.170 Melt viscosity 13 X 10 ^s Pa * s

Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Example 1 Comparative Example 2 Welding condition Welding good Welding not possible Welding good Welded end No leaked part-Leaked part Leaked part treatment Not implemented Shape Leaked part Edge appearance Good Scratches

Crack rating Tensile strength (kgf m) 51.0 56.0 56.8 58.0 54.0 54.0 54.0 Value Elongation at weld (%) 100 120 170 180 182 20-65 160 Specific gravity of weld coating 2.152 2.200 2.162 2.146 2.138 2.139 2.139 Specific gravity of weld periphery 2.157 2.160 2.162 2.161 2.158 2.155 2.155

Resin matrix modified polytetrafluoroethylene resin (III) sheet Specific gravity 2.170 Melt viscosity 13 X 10 ⁸ Pa * s

Example 1 Example 2 J Example 3 Example 4 Example 5 Comparative Example 2

Nucleophilicity Good welding Good welding Welded end No leaked part Leaked part Welded part treatment Not implemented Leaked part

Edge 舰 Good Scratches Crack rating Tensile strength (kgf / cm) 51.0 56.0 56.8 58.0 54.0 54.0 54.0 t

-4 value Weld extension (%) 100 120 170 180 182 20 ~ 65 160

Specific gravity of weld coating 2.152 2.200 2.162 2.146 2,138 2,139 2.139 Specific gravity of weld periphery 2.157 2.160 2.162 2.161 2,158 2.155 2.155

¾6 Resin matrix modified polytetraf / leo ethylene resin (III) glass backing sheet Specific gravity 2.160 Melt viscosity 13X 10 ⁸ Pa, s

Example 1 Example 2 Example 3 Example 4 1 Example 5 Comparative Example 1 Comparative Example 2

Welding condition Welding good Welding not possible Welding good Welded end No leaked part One leaked part Leaked part treatment Implemented Not implemented

Leak

Good edge appearance Good scratches Cracks

One bow tension (kgf / cm) 54.0 56.0 56.8 58.0 54.0 54.0 54.0 t

00 value

Weld elongation (%) 43 45 43 46 45 20-45 48

Specific gravity of weld coating 2.145 2.180 2.159 2.145 2.140 2.138 2.138 Specific gravity of weld periphery 2.150 2.153 2.155 2.156 2.154 2.150 2.150

7 From the above table, it was found that in Examples 1 to 5 in which the modified PTFE resin was used as a raw material of the (welding) coating material, no leaked portion was formed. In Comparative Example 2 using PFA, it was found that a leaked portion 51 as shown in FIG. 5 was generated, and when this was removed, the welded end 52 of the (resin) base material was damaged. Further, Examples 2 to 5 in Table 2 using a modified PT FE resin having a lower melt viscosity than the (resin) base material as the raw material of the (welding) coating material show that the TFE homopolymer is used as the raw material of the (welding) coating material. It was found that the welding condition was better than Comparative Example 1 used or (Comparative Example 2) using PFA as a raw material for the coating material (welding). Reference Example 1 Chemical exposure test for containers using primers

Using a 3 mm thick sheet made of polytetrafluoroethylene resin as the base material and the PFA used in Comparative Example 2 as the covering material, a primer (dispersion stabilization of the PFA obtained by emulsion polymerization using a surfactant, etc.) The welded body was welded under the same conditions as in Comparative Example 2 through the above dispersion.

The resulting conjugate was exposed to sulfuric acid and ozone at a temperature of 120 for two months, and observed using a scanning electron microscope (SEM). It was found that dust was generated at the boundaries of the area.

Based on the obtained SEM images, we observed the number of dust particles with an average particle diameter of 0.2 μπι or more per unit volume lm1 at the boundary between the base metal and the coating using a dust counter. It was 15 Zml. Further, when the elongation and the tensile strength of the welded portion were measured in the same manner as in Example 1, the tensile strength of the welded portion was reduced by 20% and the elongation was also reduced by 35% compared to before the above-mentioned exposure. Next, elemental analysis of the black part using a mass spectrometer showed that the fluorine content was reduced to 50% or less of the normal part which did not change to black.

Normal part (%) Black part (%)

Fluorine content 76 14

Carbon content 24 43

From the above results, it was presumed that dust observed by SEM was due to the generation of free floating foreign matter due to carbonization of the surfactant contained in the primer. Industrial applicability

Since the welding cladding material and the welding method according to the present invention are configured as described above, after the welding, there is little chemical solution permeation at the joint portion of the resin base material, welding reliability is excellent, and no welding portion is formed. Construction products can be provided.

Claims

The scope of the claims

1. A weld coating made of a modified polytetrafluoroethylene resin (A), wherein the weld coating is placed on a joint of a resin base material made of a polytetrafluoroethylene resin (B). To cover the joint of the resin base material by performing welding.

The modified polytetrafluoroethylene resin (A) is composed of tetrafluoroethylene and a trace amount of monomer.

Weld coating material characterized by the above.

2. Modified polytetrafluoroethylene resin (A) is a copolymer of tetrafluoroethylene having a trace monomer unit derived from a trace monomer and the trace monomer being 0.0. 2. The weld cladding material according to claim 1, wherein the content is 5 to 0.00% by mass.

3. The weld coating material according to claim 1, wherein the trace amount monomer is perfluoro (alkylbutyl) ether and / or hexafluoropropylene.

4. Range first billing melt viscosity of ^{1 X 1 0 8 ~1 5 X} 1 0 8 P a · s, 2 or welding dressing according item 3.

5. The weld cladding material according to claim 1, 2, 3, or 4, wherein the resin matrix is a lieing sheet matrix.

6. A joint structure comprising a weld coating material composed of a modified polytetrafluoroethylene resin (A) and a resin base material composed of a polytetrafluoroethylene resin (B),

It is obtained by placing the welding covering material on the joint of the resin base material and performing welding,

The modified polytetrafluoroethylene resin (A) comprises tetrafluoroethylene and Consisting of a trace amount of monomer

A joint structure characterized by the above-mentioned.

7. The modified polytetrafluoroethylene resin (A) is a copolymer of tetrafluoroethylene having a trace monomer derived from a trace monomer and the trace monomer.

7. The joined structure according to claim 6, wherein the content is 0.05 to 0.7% by mass.

8. The joint structure according to claim 6, wherein the trace amount monomer is perfluoro (alkylbutyl) ether and / or hexafluoropropylene.

9. The joint structure according to claim 6, 7, or 8, wherein the weld coating material has a melt viscosity (a) of 1 × 10 ⁸ to 15 × 10 ⁸ Pa · s.

10. The joined structure according to claim 9, wherein the melt viscosity (a) is equal to or less than the melt viscosity (b) of the resin base material.

1 1. Polytetrafluoroethylene resin (B) is a modified polytetrafluoroethylene resin (B1) composed of tetrafluoroethylene and a trace amount of monomer. No primer is used between the material and the weld coating,

The primer is made of perfluoro resin (C),

The Pafuruoro resin (C), 6, 7 the claims is intended melt viscosity is less than ^{1 X 10 5 P a · s} , 8, 9 or 1 0, wherein the bonding structure according.

12. The joint structure according to claim 6, 7, 8, 9, 10, or 11, wherein no leakage portion exists.

13. The modified polytetrafluoroethylene resin (A) is a copolymer in which a trace monomer unit derived from a trace monomer is composed of tetrafluoroethylene and the trace monomer. 0.05 to 0.5% by mass of

The joint structure according to claim 6, 8, 9, 10, 10, 11, or 12, wherein the specific gravity of the weld coating portion derived from the weld coating material is 2.145 to 2.210.

14. The joined structure according to claim 6, 7, 8, 9, 9, 10, 11, 12, or 13, wherein the resin base material is a linda sheet base material.

1 5. Welding is carried out by placing a welding coating made of modified polytetrafluoroethylene resin (A) on the joint of a resin base material made of polytetrafluoroethylene resin (B). A welding construction method,

A welding construction method characterized by that.

16. Modified polytetrafluoroethylene resin (A) is a copolymer in which a trace monomer unit derived from a trace monomer is a copolymer of tetrafluoroethylene and the trace monomer. 6. The welding method according to claim 1, wherein the amount is 0.7 mass%.

17. The welding method according to claim 15, wherein the trace monomer is perfluoro (alkylbutyl) ether and phenol or hexafluoropropylene.

1 8. The weld cladding material has a melt viscosity (a) of 1 × 10 ⁸ to 15 × 10 ⁸ Pas

The welding construction method according to claim 15, wherein the melt viscosity (a) is a value equal to or less than the melt viscosity (b) of the resin base material.

1 9. The joint of the resin base material is made by filling two resin base materials with a groove and abutting them, and filling the recess formed by this with a welding rod. The welding rod is made of perfluoro resin (D),

The Pafuruoro resin (D) are those melt viscosity is less than ^{1 X 1 0 5 P a ·} s,

The filling of the welding rod is performed by applying a pressure of 0.3 to 2.5 MPa at a welding speed of 70 to 20 Omm / min while heating the welding rod to 460 to 550 ° C. The welding method according to item 15, 16, 17 or 18.

20. The resin base material is the lining sheet base material,

The welding was performed at a welding speed of 30 to 14 Omm / min at a welding speed of 0.3 to 2.5 MPa while heating so that the contact surface between the joint of the resin base material and the weld coating material was 520 to 620 ° C. 10. The welding construction method according to claim 15, wherein the welding is performed by applying pressure.

21, The resin base material has a specific gravity of 2.175 to 2.200, and the modified polytetrafluoroethylene resin (A) has a trace monomer unit derived from a trace monomer of tetrafluoromonomer. 20. The welding work according to claim 15, 17, 18, 19, or 20, wherein the amount of the copolymer consisting of ethylene and the trace monomer is 0.05 to 0.5% by mass. Method.

22. The welding method according to claim 15, 15, 16, 17, 18, 19, 20, or 21, wherein the welding does not cause a leak.

23. Polytetrafluoroethylene resin (B) is a modified polytetrafluoroethylene resin (B1) composed of tetrafluoroethylene and a trace amount of monomer. It is to be placed on the joint of the resin base material without using a primer on the top,

The primer is composed of perfluoro resin (C),

23. The perfluoro resin (C) having a melt viscosity of 1 × 10 ⁵ Pa.s or less, according to claim 15, 16, 17, 18, 19, 20, 21, or 22. Welding construction method.

24. A welding structure according to claim 15, 16, 17, 17, 18, 19, 20, 21, 22, or 23, which is a joint structure composed of a joint portion of a resin base material and a welding cladding material. Obtained by the method

A joint structure characterized by the above-mentioned.

25. It has the joint structure according to claim 6, 7, 8, 9, 10, 11, 11, 12, 13, 14, or 24.

A welded product characterized in that:

26. The welded product according to claim 25, which is a welding lining material.

27. A composite article comprising a base material and the welded product according to claim 25 or 26.

28. The composite article according to claim 27, which is a container, a tank, a tank, a tower, a piping material, a joint, or a stirring blade.

29. The composite article according to claim 28, which is used for a semiconductor manufacturing apparatus.