JPS62148234A - Manufacture of electric wire insulated with thermoplastic aromatic polyether ketone - Google Patents

Abstract

PURPOSE:To obtain a high-reliability and heat-resistant electric wire which hardly contains foreign matters in an insulation layer and is superior in an external appearance, by removing the foreign matter contained into resin raw materials and that generated at the time of melting and extruding processing with a filter having deep layer filtering structure whose void is more than 50%. CONSTITUTION:An additive such as a lubricant or a heat-resistant stabilizer or a pigment, or an inorganic filler for an improvement in surface characteristics may be blended with thermoplastic aromatic polyether ketone. On the other hand, a foreign matter shows one contained in resin raw materials originally or generated and mixed up at a synthetic process or a mold processing process, which can not be melted and dispersed sufficiently by the final extrusion molding process. A matter whose molecular weight is extremely high and melting and dispersion cannot be accomplished even if the matter is of the same ingredient with the raw material resin is included in this one. A filter having deep layer filtering structure is a thing having three dimensional netted structure which has possessed numberless contact points among nutual fibers by performing uniformly lamination sintering of a metallic fiber whose diameter is several mum. In addition to the above, as a void largely affects the aging of a discharge quantity the void of more than 50% is favorable.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention provides a method for manufacturing a highly reliable heat-resistant electric wire having an insulating layer made of thermoplastic aromatic polyetherketone, which is free from foreign matter and has an excellent appearance. It is related to

[Prior art]

Thermoplastic aromatic polyether ketone has an extremely high elution temperature and an extrusion processing temperature of 350°C to 400°C. In addition, during the molding process (crosslinking of two resins, reaction with impurities, etc.) more insoluble and infusible substances develop pressure and become new foreign matter, which significantly impairs the appearance of the extruded product. The wire mesh used in the manufacturing process was completely overlapped with the extruder (two extruders were installed, but this did not provide sufficient overflow effect, and there was also the problem of clogging (the resin pressure would rise and the wire mesh would break).

[Purpose of the invention]

The inventor of the present invention has conducted intensive studies to find a method for removing foreign substances using resins with extremely high flow start temperatures, and found that it is most effective to use a filter with a deep filtration structure with a porosity of 50% or more. The present invention was achieved by discovering that it can be removed and also withstand long-term operation without damaging the filter.

[Structure of the invention]

That is, 1) the present invention is a thermoplastic aromatic resin which is characterized in that foreign substances contained in resin raw materials and foreign substances generated during extrusion molding are removed by a filter having a deep filtration structure with a porosity of 50% or more; Method for manufacturing polyetherketone insulated wire (Related to 1).

The thermoplastic aromatic polyether ketone may be blended with additives such as lubricants, heat stabilizers, pigments, and inorganic fillers for improving surface properties.

On the other hand, foreign matter refers to resin raw materials (foreign matter contained in the resin raw material), foreign matter generated during the synthesis process, molding process, and foreign matter that does not fully melt and disperse until the final extrusion molding process.
Even though the ingredients are the same as the raw resin, the molecular weight is extremely large, making it difficult to melt and
This includes items that cannot be fully dispersed. Foreign substances generated during the molding process (2) are substances that are difficult to melt and disperse due to crosslinking or reaction with impurities.In particular, if substances with epoxy groups are present, even a small IJl' will rapidly (1 Reacts to produce a cured product.

In addition, the filter having a deep layer superstructure used in the present invention (1) has a three-dimensional network structure in which the fibers have countless bonding points by sintering metal fibers of several diameters in uniform (2 m layers). The metal fiber is preferably made of corrosion-resistant stainless steel.Furthermore, the porosity has a large effect on changes in discharge rate over time, etc., so the porosity should be 50% or more, preferably 70% or more.

If it is less than 50%, it will be close to a general wire mesh (2), and long-term driving will be noisy.

The wire coating can be done by attaching a rad die to the tip of the f-filtration device (two crosses) and carrying out the entire culm continuously, or by extruding the resin at one end into strands (two extrusions and cutting them into granules, and then transferring them to another wire extrusion device). Do this using

〔Effect of the invention〕

The thermoplastic aromatic polyether ketone insulated wire manufactured by the manufacturing method of the present invention contains almost no foreign matter in the insulating layer and has an excellent appearance, making it ideal as a method for manufacturing highly reliable heat-resistant wires. It has been found.

The thermoplastic aromatic polyether ketone core wire produced by the method of the present invention is suitable for high reliability applications such as nuclear reactors, irradiation equipment, aircraft, oil fields, and magnet wires.

〔Example〕

Thermoplastic aromatic polyetherketone (38p manufactured by ICI)
) with an extruder (secondary melting f overaccuracy 20 μm, porosity 8
After filtration with a filter with a 0% deep filtration structure, an electric wire was produced by using a RAD die to cross the wire and insulating it with a silver-plated copper wire C having a wire diameter of 0.8%φ and a wall thickness of 0.6%.

The appearance and mechanical strength of the coating layer were investigated. Table this result.
1 (: Show.

Table 1 In this way, it was possible to remove most of the C2 foreign matter, and it was possible to obtain an electric wire with a vague and stretchy appearance.

Claims (1)

[Claims] A method for producing a thermoplastic aromatic polyoleketone insulated wire, characterized by removing foreign substances contained in resin raw materials and foreign substances generated during melt extrusion processing using a filter having a deep filtration structure with a porosity of 50% or more. .