JPH01168918A - Conjugated yarn - Google Patents

Abstract

PURPOSE:To obtain conjugated yarn having improved corrosion resistance and stain resistance without lowering yarn strength, having a volume ratio of sheath layer of a specific value, consisting of a core layer comprising a thermoplastic resin and the sheath layer comprising a thermoplastic resin containing a specific amount of copper powder having specific particle diameters. CONSTITUTION:Conjugated yarn suitable for fishing nets, etc., obtained by extruding a thermoplastic resin (e.g., polyethylene) for core layer and a thermoplastic resin (e.g., polypropylene) containing 5-50wt.%, preferably 20-30wt.% copper powder having 30mum, preferably 1-12mum average particle diameter for sheath layer form a double layer nozzle and has a core sheath structure and 10-80%, preferably 40-60% volume ratio of the sheath layer.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a composite fiber suitable for manufacturing materials for the fishery industry, particularly fishing nets, ropes, etc. used in cultivating fish.

[Conventional technology]

Fibers used for materials for the fisheries industry, especially fishing nets and ropes for fish farming, have excellent corrosion resistance, antifouling properties such as reducing the adhesion of algae and shellfish, and abrasion resistance, and are high in strength. is required.

For this reason, conventional methods have been to use wire mesh, which is less susceptible to adhesion of marine life, and to use nets and ropes made from thermoplastic resin @Kero coated with an antifouling agent mainly consisting of tin-based compounds. Furthermore, fishing nets and ropes made from thermoplastic resin filaments mixed with copper powder have been proposed.

[Problem that the invention seeks to solve]

However, the above-mentioned wire mesh is rapidly corroded by seawater and becomes unusable after about one and a half years, and not only must it be replaced, but it also has the disadvantage that it is extremely difficult to dispose of the replaced wire mesh. - In the method of applying an antifouling agent based on force field compounds, the antifouling agent is highly toxic;
The drawback is that the labor costs for drying and other processes increase, making it expensive.

In addition, by kneading copper powder into thermoplastic resin, ``the copper powder that is effectively used is only the copper powder on the surface layer, and the copper powder in the center of the filament is hardly used, and the cost is high. ,
This has the disadvantage of reducing fiber strength.

In view of the above circumstances, the present invention provides a composite material that effectively utilizes kneaded copper powder, does not reduce fiber strength, has excellent corrosion resistance and antifouling properties, and is suitable for manufacturing fishing nets, robes, etc. in the fisheries industry. The purpose is to provide fiber.

[Means for solving problems]

The present invention has been made to achieve the above object, and its gist consists of a core layer made of a thermoplastic resin and an average particle size of 30.
A core-sheath type composite fiber composed of a sheath layer made of a thermoplastic resin containing 5 to 50 wt% of copper powder of 5 to 50 μm or less, the volume ratio of the sheath layer to the composite fiber being 10 to 50% by weight.
80%.

[Specific structure and operation of the invention]

Examples of thermoplastic resins used as the core layer resin component in the present invention include polyolefin resins such as polyethylene (PE) and polypropylene (PP), and polyamide resins such as nylon 6, nylon 66, nylon 11, and nylon 12. can give.

In addition, thermoplastic resins used as the resin component for the sheath layer include polyolefin resins such as PE and PP, polyamide resins that improve stain resistance, ethylene/acid-vinyl copolymer (EVA), ethylene・Hydrophilic resins such as methacrylic acid copolymer (EMAA), ethylene/acrylic acid copolymer (FAA), ethylene/ethyl acrylate copolymer (EEA), etc. alone or in combination with PE
A resin composition that is a blend of

Conventional additives such as antioxidants, heat stabilizers, weathering agents, lubricants, dyes, and pigments may be added to the thermoplastic resins used as the core layer resin component and the sheath layer resin component.

The combination of the resin component for the core layer and the resin component for the sheath layer does not reduce the physical performance of the composite fiber, so it has excellent mutual adhesion and exhibits similar spinnability and drawability under the same spinning conditions. Those who do are selected.

To give a specific example of the combination of the resin component for the core layer and the resin component for the sheath layer, when the resin component for the core layer is PE, the resin component for the sheath layer is a polyolefin resin film such as PE or PP, or Polyamide resin, EvA, EMAA, EAASE
Examples include the use of EA alone or a combination of a blended resin composition of EA and PE. In addition, when the resin component for the core layer is a polyamide resin, the resin component for the sheath layer can be polyamide resin, EVA, EMAA, EAA,
EEA may be used alone or a combination of EEA and PE may be used in a blended resin composition.

In the present invention, the copper powder mixed into the resin component for the sheath layer is
The average particle size (hereinafter referred to as particle size) is 30 μm or less, preferably 1 to 20 μm, particularly 1 to 12 μm.

When the particle size of the copper powder exceeds 30 μm, the formability and mechanical performance of the resulting composite fiber deteriorate.

The amount of copper powder mixed into the resin component for the sheath layer is 5 to 50wt.
%, preferably 10 to 40 wt%, particularly preferably 20 to 30 wt%. The amount of copper powder added is 5
If it exceeds 0 wt%, the moldability and mechanical performance of the composite fiber obtained will deteriorate, and if it is less than 5 wt%, the antifouling effect will decrease.

The volume ratio of the sheath layer in the composite fiber is within the range of 10 to 80%, preferably 30 to 70%, particularly 40 to 6%.
0% is preferred. When the capacity ratio of the sheath layer is less than 0%,
Not only does the layer structure become disordered during molding, but the antifouling effect is short-lived and its sustainability is lost. Furthermore, if the volume ratio of the sheath layer exceeds 80%, the antifouling effect will not be improved, the moldability and mechanical performance will deteriorate, and copper powder will be used unnecessarily, resulting in a loss of economic efficiency.

The composite fiber of the present invention can be produced by a conventionally known method. For example, first, a predetermined amount of copper powder is added to the resin component for the sheath layer and kneaded to form pellets. Next, these pellets and the resin component for the core layer are each filled into two extruders, held at a predetermined temperature, and extruded from a two-layer nozzle heated to a predetermined temperature to spin composite fibers.
A composite fiber can be produced by cooling with water at a predetermined temperature, then stretching it to a predetermined magnification in hot water at a predetermined temperature, and winding it up.

〔Example〕

Next, the present invention will be explained in further detail by showing Examples and Comparative Examples.

Examples 1 to 8 and Comparative Examples 1 to 5 Ml was 0.7 g/10 min (190
℃, load 2.16 kg, hereinafter the same), using high density polyethylene (referred to as HDPE-1) with a melting point of 130 ℃, MI of 1.2 g / 10 minutes, melting point 1 as the resin component for the sheath layer.
Using a resin made of high-density polyethylene (called HDPE-2) at 28°C mixed with copper powder of various particle sizes in various proportions,
By changing the volume ratio of the sheath layer in the composite fiber,
A μm composite fiber was produced.

Manufacture of composite fibers uses two extruders, HDPE-1
was extruded at 280°C, HDPE-2 was extruded at 270°C,
The composite yarn was spun using a two-layer nozzle heated to 30°C.
After cooling with cold water at 98°C, it was stretched 10 times in hot water at 98°C. In addition, for the single yarn, HD PE-2 was used, and 2
The fibers were spun using a single-layer nozzle heated to 70°C, cooled to 30°C, and then stretched 10 times.

The moldability, strength, and stain resistance of these composite fibers and single yarns were investigated. The antifouling properties were determined by leaving a net made of fibers in the sea for 6 months and observing the state of contamination.

The results are shown in Table 1.

Below Margin Examples 9 to Summer 3 and Comparative Examples 6 to 9 HDPE-1 same as Examples 1 to 8 and Comparative Examples 1 to 5
, EVA with a melting point of 86°C (vinyl acetate content 15%)
and polyamide (nylon 6) with a melting point of 215°C. EVA is extruded at 150°C and polyamide is extruded at 260°C. Only when the sheath is EVA, the stretching ratio is 8.5, and for other cases, the stretching ratio is Example 1 except that 4.5 was set.
Composite fibers with a diameter of 200 μm were produced in the same manner as in Comparative Examples 1 to 8 and Comparative Examples 1 to 5.

The moldability, strength, and antifouling properties of these were investigated.

The results are shown in Table 2.

Margins below [Effects of the Invention] As described above, the composite fiber according to the present invention has the core-sheath structure specified above, and therefore has good formability, high strength, and a reduced amount of copper powder used. Although it is relatively small in amount, it has excellent antifouling properties, is inexpensive, and has many advantages as a fiber for the fishing industry, such as fishing nets and ropes for aquaculture.

Claims (1)

[Claims] A core-sheath type composite fiber composed of a core layer made of a thermoplastic resin and a sheath layer made of a thermoplastic resin containing 5 to 50 wt% of copper powder with an average particle size of 30 μm or less,
A conjugate fiber characterized in that the volume ratio of the sheath layer in the conjugate fiber is 10 to 80%.