JPH0596598A - Fluorocarbon resin composite pipe manufacturing method - Google Patents

Abstract

(57) [Summary] [Structure] Fluorine-based thermoplastic resin is extruded from the first extruder 1, and the extruded pipe 2 is continuously cooled by the cooling device 3 and continuously dried by the drying device 4 to be applied. After the adhesive is continuously applied by the device 5, the adhesive is passed through the crosshead die 7 of the second extrusion molding machine 6, and a general-purpose thermoplastic resin such as vinyl chloride resin is piped from the second extrusion molding machine 6. Extrusion molding is performed on the outer peripheral surface of No. 2 to produce a composite pipe including a fluorine-based thermoplastic resin layer, an adhesive layer, and a general-purpose thermoplastic resin layer. [Effect] A composite pipe in which a fluorine-based thermoplastic resin layer and a general-purpose thermoplastic resin layer are firmly adhered by an adhesive layer can be efficiently manufactured, and the non-contaminating property of the fluorine-based thermoplastic resin is not impaired. It is suitable as a pipe for transferring pure water.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a fluororesin composite pipe, and more particularly to a method for producing a pipe suitable for transferring ultrapure water or the like. In the following description, vinylidene fluoride polymer is PVDF, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer is PFA, tetrafluoroethylene-hexafluoropropylene copolymer is FEP, tetrafluoroethylene-ethylene copolymer. Is abbreviated as ETFE, polychlorotrifluoroethylene as abbreviated as PCTFE, and chlorotrifluoroethylene-ethylene copolymer as abbreviated as ECTFE.

[0002]

2. Description of the Related Art With the recent remarkable development of the semiconductor device-related industry, the amount of ultrapure water used has increased and the demand for pipes for transferring ultrapure water has increased rapidly. Heretofore, attempts have been made to use a pipe made of a fluorine-based thermoplastic resin such as PVDF as a pipe for ultrapure water, but since these resins are very expensive, only the inner peripheral surface of the pipe is used. An improved method using an inexpensive resin such as vinyl chloride resin or ABS resin as most of the materials including the resin layer and the outer peripheral surface of the pipe is disclosed in, for example, Japanese Patent Laid-Open No. 61-171983 or Japanese Utility Model Laid-Open No. 61-1983. 16473
No. 0 publication. In particular, the actual development Sho 61-1647
No. 30 discloses a PVD used as a material for the inner peripheral surface layer in order to improve the interfacial adhesion between the inner peripheral surface layer and the outer peripheral surface layer.
One or both of F and the general-purpose thermoplastic resin used as the material for the outer peripheral surface layer may be copolymerized with an ethylenically unsaturated carboxylic acid ester, or a polymer of an ethylenically unsaturated carboxylic acid ester or another copolymerizable resin. A method of incorporating a copolymer with another monomer, 2) a method of providing an adhesive layer (adhesive, pressure-sensitive adhesive, etc.) between the inner and outer peripheral layers are proposed.

However, the actual exploitation of Sho 61-164730
Japanese Patent Application Laid-Open No. 2003-242242, that is, a method for copolymerizing an ethylenically unsaturated carboxylic acid ester component with a fluorine-based thermoplastic resin such as PVDF which is a material for the inner peripheral surface layer in order to improve the adhesion between the two layers. The method 1) of incorporating by a blending method of a polymer of the ester or the ester has a problem of deteriorating the non-contaminating property of the fluorine-based thermoplastic resin with respect to ultrapure water, and in order to avoid this problem, the outer peripheral surface is When only the general-purpose thermoplastic resin of the layer is modified by the above method, there is a problem that the adhesion between the two layers becomes insufficient. In addition, 61
Japanese Patent Laid-Open No. 164730-1994 does not disclose a specific method of forming an adhesive layer between two layers by providing an adhesive layer by an extrusion molding method.

[0004]

DISCLOSURE OF THE INVENTION The present invention is intended to solve the problems described above without deteriorating the non-contaminating property of the fluororesin with respect to ultrapure water.
It is intended to provide a method for efficiently producing a fluororesin composite pipe having sufficient adhesion between layers.

[0005]

That is, the present invention uses two extruders to continuously extrude a fluorinated thermoplastic resin into a pipe by the first extruder to form the pipe. After being continuously cooled and dried, an adhesive is continuously applied to the surface of the pipe and passed through a crosshead die of a second extruder installed almost at right angles to the traveling direction of the pipe. At the same time, the present invention is directed to a method for producing a fluororesin composite pipe, characterized in that a general-purpose thermoplastic resin is extruded on the outer peripheral surface of the pipe by a second extruder.

The fluorine-based thermoplastic resin used in the present invention includes PVDF, PFA, FEP, ETFE and PC.
Examples thereof include TFE and ECTFE, which are used alone or in 2
Used in combination of two or more species.

Examples of general-purpose thermoplastic resins used in the present invention include vinyl chloride resins, ABS resins, olefin resins and the like, and these may be used alone or in combination of two or more.

A method of manufacturing the fluororesin composite pipe of the present invention will be described with reference to FIG. 1 showing manufacturing equipment. Fluorine-based thermoplastic resin is extruded into a pipe shape from the first extrusion molding machine 1. The extruded pipe 2 is continuously cooled by the cooling device 3 and then continuously dried by the drying device 4. As the cooling device 3, a system of passing a pipe through a cooling water tank, a system of showering cooling water on the pipe, or the like is used. As the drying device 4, a heater, a hot air blowing machine, or the like is used. The dried pipe 2 is sent to the adhesive application device 5, and the adhesive is continuously applied to the surface of the pipe. As the adhesive application device 5, for example, as shown in FIG. 3, a system of spraying the adhesive 8 onto the surface of the pipe 2 by a spray gun 9, a system of passing the pipe through an adhesive tank, or the like is used. To use.

Next, the pipe 2 coated with the adhesive is passed through a crosshead die 7 of a second extruder 6 installed at a right angle to the traveling direction of the pipe, and the second pipe A general-purpose thermoplastic resin 8 is extrusion-coated on the outer peripheral surface of the pipe 2 by an extrusion molding machine 6 to obtain a composite pipe 10.

As described above, a composite pipe in which the fluorine-based thermoplastic resin layer 11, the adhesive layer 12, and the general-purpose thermoplastic resin layer 13 are laminated in this order as shown in FIG. 2 is obtained.

[0011]

The present invention will be described in more detail based on the following examples, but the invention is not intended to be limited thereto. Example 1 First 40 mmφ extruder (FS manufactured by Ikegai Tekko KK
Set the cylinder temperature of 40) to 340 to 360 ° C,
The specific gravity of 2.15 (ASTM
D792), a melting point of 270 ° C. (ASTM D3418), FEP (Solvey FSOL), is introduced to extrude a pipe having an inner diameter of 44 mm and an outer diameter of 46 mm,
This pipe was continuously cooled by a showering of cooling water, blown with warm air to be continuously dried, and then the main component and the curing agent were sufficiently mixed in a weight ratio of 1: 1 in advance until uniform. Adhesive (made by Cemedine Co., EP-
No. 001) was continuously applied to the surface of the pipe by an applicator shown in FIG. 3, and a second 50 mmφ extruder (FS5 manufactured by Ikegai Iron Works Co., Ltd.) installed perpendicularly to the traveling direction of the pipe.
It was passed through the cross head die of 0).

On the other hand, the cylinder temperature of the second extruder is set to 175 to 185 ° C., and the hopper of the extruder is filled with a lead-based heat stabilizer (Tribase T manufactured by Sakai Chemical Industry Co., Ltd.).
L7000) blended with an average degree of polymerization of 1250 (JIS
K6721) vinyl chloride resin (Kanefuchi Chemical Industry Co., Ltd., Kanevinyl S1003) was charged and extruded, and then passed through the crosshead die, to the outer peripheral surface of the FEP pipe coated with the adhesive. About 2 parts of the vinyl chloride resin
Extruded by adhering to a wall thickness of mm, inner diameter 44 mm, outer diameter 5
A 0 mm composite pipe was obtained.

Example 2 Using the equipment used in Example 1, the cylinder temperature of the first extruder was set to 350 to 360 ° C., and the specific gravity of 2.15 (ASTM D79) was set in the hopper of the extruder.
2), PFA with a melting point of 305 ° C (ASTM D3418)
(Solvey PFA manufactured by Solvay Co., Ltd.)
A pipe having an inner diameter of 44 mm and an outer diameter of 46 mm was extruded, the pipe was continuously cooled by a shower ring of cooling water, blown with warm air to be continuously dried, and then the adhesive used in Example 1 was used. The same adhesive was continuously applied to the pipe surface by an applicator and passed through the crosshead die of the second extruder, which was installed at right angles to the direction of travel of the pipe.

On the other hand, the cylinder temperature of the second extruder is set to 265 to 275 ° C., and a heat-resistant ABS resin (manufactured by Kanegafuchi Chemical Industry Co., Ltd.) having a specific gravity of 1.05 (ASTM D792) is added to the hopper of the extruder. , Kane Ace MUH M-
3000) is put in and extruded, and the heat-resistant ABS resin is adhered to the outer peripheral surface of the PFA pipe having the adhesive applied to the surface passing through the crosshead die to a thickness of about 2 mm and extruded. A composite pipe having an inner diameter of 44 mm and an outer diameter of 50 mm was obtained.

COMPARATIVE EXAMPLE 1 A first 40 mmφ extruder (FS40, manufactured by Ikegai Tekko KK) was used with a cylinder temperature of 230 by using equipment comprising two extruders and one common head die. ~ 2
The specific gravity is set to 40 ° C., and the hopper of the extruder has a specific gravity of 1.
78 (ASTM D792), melting point 178 ° C. (ASTM
D3418) PVDF (Solvey, Solef)
PVDF) 100 parts by weight of a copolymer containing methyl methacrylate as a main component, and 0.4 g of the copolymer.
A methyl methacrylate copolymer (Kaneace PA-20, manufactured by Kanegafuchi Chemical Industry Co., Ltd.) having a specific viscosity of 1.4 in 100 ml of a toluene solution containing 10%, which is 1.4, was measured.
A PVDF resin composition mixed in parts by weight is charged and extruded, and at the same time, the cylinder temperature of a second 50 mmφ extrusion molding machine (FS50, manufactured by Ikegai Tekko KK) is set to 255 to 265 ° C.
And the same heat-resistant ABS resin as used in Example 2 was charged into the hopper of the extruder and extruded, and these extrudates were mixed with a common head die (set temperature: 250).
The inner diameter of the extrudate produced by the first extruder is 1 mm as the inner peripheral surface layer, and the extrudate produced by the second extruder is 2 mm as the outer peripheral layer. 44 mm,
A composite pipe with an outer diameter of 50 mm was obtained.

Comparative Example 2 Using the equipment used in Comparative Example 1, the cylinder temperature of the first extruder was set to 230 to 240 ° C., and the hopper of the extruder had a specific gravity of 1.78 (ASTM D79).
2), PVD with a melting point of 178 ° C (ASTM D3418)
F (Solvey PVDF, manufactured by Solvay Co., Ltd.) was charged and extruded, and at the same time, the cylinder temperature of the second extruder was set to 255 to 265 ° C., and the hopper of the extruder was used in Example 2. Same heat resistant ABS resin 1
A heat-resistant ABS resin composition containing 20 parts by weight of the same methyl methacrylate copolymer as that used in Comparative Example 1 was added to 100 parts by weight, and the mixture was extruded. At a set temperature: 250 ° C, the extrudate from the first extruder has a wall thickness of 1 mm as the inner peripheral surface layer, and the extrudate from the second extruder has a wall thickness of 2 mm as the outer peripheral surface layer. A composite pipe having an inner diameter of 44 mm and an outer diameter of 50 mm was obtained.

FIG. 4 shows a test piece for cutting the composite pipes obtained in Examples 1 and 2 and Comparative Examples 1 and 2 to measure the tensile shear strength of the adhesive surface between the inner peripheral surface layer and the outer peripheral surface layer. Five pieces were prepared for each of the examples and comparative examples according to the shape shown, and these were left in a thermostatic chamber at 23 ° C. for 48 hours and then at 50 ° C. at 23 ° C.
Tensile at a speed of 0 mm / min, the strength at break of the adhesive layer was measured by an autograph, and the average value of the obtained five measured values was calculated. The measurement results are shown in Table 1.

The pipes obtained in Examples 1 and 2 and Comparative Examples 1 and 2 were cut into three pipes each having a length of 15 cm, and the following operations were performed in a clean room to check the contamination with ultrapure water. evaluated. First, after thoroughly wiping the inner surfaces of these pipes with ultra pure water having a total organic carbon concentration (hereinafter referred to as TOC) of 8 ppb, a liquid cleaning agent (Daiichi Clean Chemical Co., Ltd., product (Name: Scat 20X-PF5% solution) (150 ml) was put, both ends of the pipe were sealed, and shaken for 4 hours with a shaker. Next, the inner surface of the pipe was washed for 2 hours while overflowing the ultrapure water, 150 ml of ultrapure water was filled in the pipe, both ends were sealed, and the mixture was shaken at 60 ° C. for 24 hours. The TOC of the ultrapure water in these pipes was measured by the method of JIS K0551, and the average value of the obtained three measured values was calculated. As a reference, the TOC of a commercially available vinyl chloride resin (PVC) pipe was also measured. The results of these analyzes are shown in Table 1.

[0019]

[Table 1]

[0020]

As described above, according to the method of the present invention, the inner peripheral surface layer made of the fluorine-based thermoplastic resin and the general-purpose thermoplastic resin made of the vinyl chloride resin, the ABS resin, the olefin resin, etc. It is possible to efficiently manufacture a composite pipe having an adhesive layer provided between the outer peripheral surface layer and the outer peripheral surface layer, and in the obtained composite pipe, the inner peripheral surface layer and the outer peripheral surface layer are firmly bonded with an adhesive, and Since it has no effect on the non-contaminating property of the thermoplastic resin, it can be suitably used as a pipe for transferring ultrapure water or the like, and has a high industrial value.

[Brief description of drawings]

FIG. 1 is a schematic view showing an example of manufacturing equipment used in the present invention.

FIG. 2 is a schematic sectional view of a fluororesin composite pipe of the present invention.

FIG. 3 is a schematic view of an adhesive applicator used in Examples 1 and 2.

FIG. 4 is a schematic view showing a shape of a test piece for measuring tensile shear strength of an adhesive portion of a fluororesin composite pipe.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 1st extrusion molding machine 2 Pipe 3 Cooling apparatus 4 Drying apparatus 5 Adhesive application device 6 2nd extrusion molding machine 7 Crosshead die 8 Adhesive 9 Spray gun 10 Composite pipe 11 Fluoro-thermoplastic resin layer 12 Adhesive layer 13 General-purpose thermoplastic resin layer

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Claims (3)

[Claims] 1. A fluorinated thermoplastic resin is continuously extruded into a pipe shape by a first extruder using two extruders, and the pipe is continuously cooled and dried. While continuously applying an adhesive to the surface of the pipe and passing it through a crosshead die of a second extruder that is installed at a right angle to the traveling direction of the pipe, A method for producing a fluororesin composite pipe, characterized in that a general-purpose thermoplastic resin is extruded on the outer peripheral surface of the pipe. 2. The fluorine-containing thermoplastic resin is vinylidene fluoride polymer, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-ethylene copolymer, poly The production method according to claim 1, which is at least one selected from the group consisting of chlorotrifluoroethylene and a chlorotrifluoroethylene-ethylene copolymer. 3. A general-purpose thermoplastic resin is a vinyl chloride resin,
The production method according to claim 1 or 2, which is at least one selected from the group consisting of an ABS resin and an olefin resin.