JPS61124335A - Monofilament for fishing net - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Industrial applications The present invention relates to monofilaments for fishing nets.

More specifically, the present invention relates to a monofilament for fishing nets that can prevent misalignment by having protrusions on the surface of the monofilament.

BACKGROUND OF THE INVENTION Conventionally, fishing nets using monofilament have been known as fishing nets in which it is extremely difficult to secure knots in the knots, often causing eye strain during fishing operations. In particular, in the case of gill nets, when fish that get stuck in the nets run wild in an attempt to escape, they can become misaligned, reducing the catch. In order to prevent this, a method of fixing the knots of the fishing net with resin is known.For example, a method of fixing the knots by knitting the knots with Kaermata knots is known. However, in the case of resin processing, the entire net hardens, non-adhesive spots can cause misalignment, yellowing, and the net is often left permanently in place. In the above-mentioned knot knitting (-guruma or double force ermata), the tightness of the knots is relatively soft (and the strength is low because stitches are misaligned).

Problems to be Solved by the Invention An object of the present invention is to provide a monofilament for fishing nets that can effectively prevent the misalignment of such conventional fishing nets.

Means for Solving the Problems, That is, the present invention is a monofilament having protrusions on its surface, and the protrusions are substantially triangular and radially arranged in four or more on the circumference of the cross section of the monofilament. This is a characteristic feature of monofilament for fishing nets.

The monofilament referred to in the present invention includes nylon 6,
Nylon 66, nylon 610, nylon 12 and other copolymerized nylons, polyethylene terephthalate, polybutylene terephthalate, and copolymerized polyesters containing these, polyethylene, polyzolopyrene,
Polyvinyl chloride 1, i? Examples include IJ vinylidene chloride. In particular, nylon is the most suitable material for gill nets due to its pure transparency, flexibility and processability.

When the monofilament of the present invention is melt-spun from nylon 6 or polyethylene terephthalate, it is important to form triangular projections on the circumference of the cross section of the filament. The protrusions formed on the surface of the monofilament may have polygonal shapes such as triangles and squares, semicircles, crescents, etc., but triangular protrusions with acute angles are effective for the purpose of preventing misalignment.

Next, the size of the triangular projection is expressed by its height h and angle θ. As shown in Fig. 4, first, the height 3h is 0.01<h<1 when the diameter of the filament is 1, and the effect is substantially greater in the range of 0.05<h<0.5. It is.

Also, the angle θ is in the range of 100 to θ<170',
In particular, the effect is remarkable in the range of 9o0 by 30°. The reason for this is that if the height h is 0.01 or less and the angle θ is 120° or more, it will be the same as without protrusions, and the threads will not bite into each other and misalignment will occur. If the angle is less than 10°, the triangular protrusion becomes extremely sharp, resulting in a whisker-like shape and no tight knots between the threads.

An enlarged view of the monofilament of the present invention is illustrated in FIG.
Its diameter is taken as 1, and the height h and angle θ are shown. Further, even if the triangular tip of the protrusion is slightly rounded, the effect on misalignment will not change.

In the present invention, "stitching" refers to a phenomenon in which the knot (knot part) of the 11#1 monofilament slips and slips due to impact or tension.

The degree of ease with which this misalignment occurs is determined by measuring the strength of the tied thread (first stitch hooked). A thread that tends to misalign will have low strength (and high elongation) because the knot will misalign.

Next, the number of protrusions formed on the surface of the monofilament in the present invention is 4 or more, preferably 8 or more so that misalignment is less likely to occur. Further, the number of protrusions is limited to about 36 at most. The reason for this is that even if you knead more than that, the effect of misalignment will reach equilibrium.

Example Examples of the present invention will be shown below.

Examples 1 to 5 100 parts of nylon 6 chips with a relative viscosity of 3.2 (1!? Polymer/100d98% sulfuric acid) were spun at a temperature of 260
Melt at °C, and measure the horizontal x vertical size of the protrusion radially by ■ [1
, I X O, 1 bird (Example 1) ■0.2 X O, 4
■ (Example 2) ■ 0.4 x 0.6 m glue (Example 6
) was spun into water at 20°C using a spinneret with a hole diameter of 1.8 mm and 2 holes.
I picked it up in 7 minutes. This filament was drawn at a first stage drawing ratio of 6.8
(hot water 95°C), and further two-stage stretching ratio 1.451 (
After stretching at 2500C (heat 1),
t131J'C) and the diameter [1,4[Jho(
A monofilament for fishing nets (1320 denier) was obtained.

Next, as a comparison, each (1) normal round cross section with no protrusions (comparative example 1) + 21 protrusions horizontal x vertical size 0.2 x 0
．． Two protrusions of 4 fl (Comparative Example 2) + 8 protrusions with horizontal x vertical size of 0.004 x 0.004 mm
(Comparative Example 3) F4) Having 8 semicircles with a diameter of 0.21 radially on a round cross section (Comparative Example 4) It was similarly extruded through the hole A2 of a spinneret with a hole diameter of 1.8 mm. When these monofilaments were used to knit a net with a netting machine, the results were determined according to JIS L1045 (1st hook strength was measured in dry and wet conditions, and the results are summarized in Table 1.

(Left below) Table 1! It is clear from Table 1 that, compared to Comparative Examples 1 to 4, Examples 1 to 3 of the present invention had higher first hook hooks in both dry and wet conditions (because of this, the fishing nets were less likely to slip off). I understand something.

Example 3 and Comparative Example 10 Strong elongation curve (time 1st catch V'
f strength) is shown in Figure 1. As shown in the figure (, Example 6 (~
The first hook is a triangular protrusion 0.4 x O,
Shin JIF is also 20, where the frequency is controlled because there is no slippage due to 6ax.
% rod degree. In contrast, comparison 1”ll IIB+
In the case of a normal round cross section, the strength was low and the elongation was high at 65% due to slippage at the joints.

It has a strong and high performance coating that does not easily cause eye misalignment.

In other words, since the monofilament with triangular protrusions is in the elongation direction (yarn axis direction), the threads can
It becomes a hole in the cross-sectional direction of the thread, and the frictional resistance becomes large.
This is because the misalignment of the fish's catch becomes large (((). As a result, the catch can be increased.

[Brief explanation of drawings]

FIG. 1 shows the strength and elongation curves of a conventional nylon A net and a fishing net using the monofilament of the present invention when hooked with one hook. FIG. 2 shows an example of a schematic cross-sectional view of the grooves of the monofilament for fishing nets of the present invention. FIG. 3 is an enlarged view of the protrusion shown in FIG. 2. FIG. 4 shows a cross-sectional view of a conventional monofilament.

Claims (1)

[Claims] A monofilament for fishing nets, which is a monofilament having protrusions on its surface, and the protrusions are substantially triangular and radially arranged in four or more on the circumference of the cross section of the monofilament.