Search

JP-2026075730-A - Core-sheath type composite monofilament and method for manufacturing the same

JP2026075730AJP 2026075730 AJP2026075730 AJP 2026075730AJP-2026075730-A

Abstract

[Problem] To provide a core-sheath type composite monofilament with improved abrasion resistance. [Solution] This core-sheath composite monofilament has a core component which is a resin composition containing a polyvinylidene fluoride resin, a polyester thermoplastic elastomer, and a low-density polyamide resin, and a sheath component which is a polyamide resin. The sheath component may also contain silicone oil as a mold release agent. The overall cross-sectional shape of the core-sheath composite monofilament is circular. The cross-sectional shape of the core component is circular or multi-lobed. A multi-lobed shape has multiple leaf portions 1 which are outwardly protruding parts, and a central portion 2 inside the leaf portions 1. This core-sheath composite monofilament is suitably used as fishing line. [Selection Diagram] Figure 1

Inventors

  • 金築 亮

Assignees

  • ユニチカ株式会社

Dates

Publication Date
20260511
Application Date
20241023

Claims (14)

  1. A core-sheath composite monofilament in which the core component is a resin composition containing a polyvinylidene fluoride resin, a thermoplastic elastomer, and a polyethylene resin, and the sheath component is a polyamide resin, wherein the overall cross-sectional shape of the core-sheath composite monofilament is circular.
  2. The core-sheath type composite monofilament according to claim 1, wherein the cross-sectional shape of the core component is circular.
  3. The core-sheath type composite monofilament according to claim 1, wherein the cross-sectional shape of the core component is multi-lobed.
  4. The core-sheath type composite filament according to claim 1, wherein the thermoplastic elastomer is a polyester-based thermoplastic elastomer.
  5. The core-sheath type composite monofilament according to claim 1, wherein the sheath component contains a release agent.
  6. The core-sheath type composite monofilament according to claim 5, wherein the release agent is a silicone-based release agent.
  7. The core-sheath type composite monofilament according to claim 3, wherein the multi-lobed shape is tri-lobed to octave-lobed.
  8. The core-sheath type composite monofilament according to claim 1, wherein the volume percentage of the core component is 10 to 35 volume%.
  9. A fishing line comprising a core-sheath type composite monofilament as described in any one of claims 1 to 8.
  10. A tennis racket string using a core-sheath type composite monofilament as the core thread, as described in any one of claims 1 to 8.
  11. A method for producing a core-sheath composite monofilament, characterized by compound melt spinning using a resin composition containing a polyvinylidene fluoride resin, a thermoplastic elastomer, and a polyethylene resin, and a polyamide resin, to obtain a core-sheath composite undrawn filament with a circular cross-sectional shape, where the core component is made of the resin composition and the sheath component is made of the polyamide resin, and then drawing the undrawn filament under heating.
  12. A method for manufacturing a core-sheath type composite monofilament according to claim 11, wherein the cross-sectional shape of the core component is circular.
  13. A method for producing a core-sheath type composite monofilament according to claim 11, wherein the cross-sectional shape of the core component is multi-lobed.
  14. A method for producing a core-sheath type composite monofilament according to claim 11, comprising compound melt spinning a polyamide resin to which a mold release agent has been added.

Description

This invention relates to a core-sheath type composite monofilament and a method for producing the same, wherein the core component is a resin composition containing a polyvinylidene fluoride resin, a thermoplastic elastomer, and a polyethylene resin, and the sheath component is a polyamide resin. In particular, the invention relates to a core-sheath type composite monofilament and a method for producing the same that are suitable for use as core threads for fishing lines or tennis racket strings. Conventionally, core-sheath composite monofilaments, in which the core component is made of polyvinylidene fluoride resin and the sheath component is made of polyamide resin, have been known (Patent Documents 1 and 2). The reason for combining polyvinylidene fluoride resin and polyamide resin is to achieve a specific gravity suitable for fishing line; that is, to have a specific gravity lower than that of polyvinylidene fluoride resin and higher than that of polyamide resin. The present inventors have proposed the invention described in Patent Document 3 as an improved invention of the invention described in Patent Document 2. The invention described in Patent Document 3 aims to provide a core-sheath type composite monofilament with high abrasion resistance by improving the adhesion between the core component and the sheath component by employing a resin composition containing a polyvinylidene fluoride-based resin and a thermoplastic elastomer as the core component. Japanese Patent Publication No. 2021-70898Japanese Patent Publication No. 2023-148093Japanese Patent Application No. 2023-151805 Specification Example 1 A resin composition was prepared by uniformly mixing 91 parts by mass of polyvinylidene fluoride resin (manufactured by Shandong Dexuan New Materials Co., Ltd., trade name "DY-11B"), a polyvinylidene fluoride-based resin; 5 parts by mass of polyester elastomer (manufactured by Mitsubishi Chemical Corporation, trade name "Modic GQ331"), a thermoplastic elastomer; and 4 parts by mass of low-density polyethylene resin (manufactured by Nippon Polyethylene Co., Ltd., trade name "UJ580"), a polyethylene-based resin. In addition, polyamide 6/polyamide 66 copolymer resin (manufactured by DSM Corporation, trade name "Novamid 2030J") was prepared as a polyamide-based resin. Using a composite melt spinning apparatus with spinning holes in a concentric core-sheath structure, composite melt spinning was performed at a melting temperature of 270°C, with the resin composition as the core component and the polyamide-based resin as the sheath component, to obtain a concentric core-sheath type composite undrawn monofilament. Furthermore, the volume ratio of the resin composition to the polyamide resin was set to 20:80 for the composite melt spinning. The resulting concentric core-sheath type composite undrawn filament had a circular cross-sectional shape, and the core component also had a circular cross-sectional shape. The concentric core-sheath type undrawn composite filament was cooled by immersion in a 40°C water bath, then immersed in a 90°C warm bath and subjected to the first stage of drawing under a moist heat atmosphere. Next, the second stage of drawing was performed under a dry heat atmosphere of 180°C, followed by a third stage of drawing under a dry heat atmosphere of 200°C. A total drawing ratio of 5.8 times was achieved to obtain a concentric core-sheath type composite monofilament. The resulting concentric core-sheath type composite monofilament had a circular cross-sectional shape, and the core component also had a circular cross-sectional shape. Example 2 A core-sheath composite monofilament was obtained by the same method as in Example 1, except that a mixture of 93 parts by mass of polyamide 6/polyamide 66 copolymer resin (manufactured by DSM Corporation, trade name "Novamid 2030J") and 7 parts by mass of masterbatch was used as the polyamide resin instead of the polyamide resin used in Example 1. The masterbatch used was a uniform mixture of 93 parts by mass of polyamide 6/polyamide 66 copolymer resin (manufactured by DSM Corporation, trade name "Novamid 2030J") and 7 parts by mass of silicone oil (manufactured by Momentive Corporation, trade name "TSF451-3000"). The cross-sectional shape of the obtained concentric core-sheath composite monofilament was circular, and the cross-sectional shape of the core component was also circular. Example 3 A concentric core-sheath composite monofilament was obtained using the same method as in Example 2, except that the total drawing ratio was changed to 6.0 times. The cross-sectional shape of the obtained concentric core-sheath composite monofilament was circular, and the cross-sectional shape of the core component was also circular. Example 4 The resin composition used in Example 1 and the polyamide resin used in Example 2 were prepared. The resin composition, which is the core component, was melt-spun and combined at a melting temperature of 270°C through seve