JPS6019431A - Raw yarn for knitting 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] The present invention relates to yarn for knitting fishing nets.

As the fixed fishing nets and aquaculture fishing nets are used, a large amount of silica shellfish attaches to them, and these grow and enlarge in a short period of time, causing blown, broken, or misplaced fishing nets in fixed fishing nets, and poor water passage in aquaculture fishing nets. This can lead to various problems such as oxygen deficiency and disease outbreaks, death of cultured fish and shellfish, and poor growth. Therefore, drying operations to remove the attached silica and shellfish must be carried out several times during the fishing season. However, the effort and expense involved are enormous. For this reason, efforts have been made to apply so-called algaecide, which is a solution of heavy metals in an organic solvent, to the net fabric, and use its medicinal killing power to prevent the attachment and growth of diatoms and shellfish, thereby reducing the need for drying the net. Its anti-algae and anti-fouling properties are extremely unclear, and on the contrary, it may kill the spores and young of seaweeds and fish and shellfish due to the elution of heavy metals, or cause deformation and toxic contamination of fish and shellfish in nearby aquaculture areas. In addition, there are many human accidents such as skin irritation due to heavy metals and inhalation fainting due to organic solvents during painting work, so it is necessary to improve handling safety in addition to algae-proofing and antifouling properties. A high netting was requested.

The inventor has been diligently researching the anti-algae and anti-fouling properties of these net fabrics from an early stage, and has developed a method of forming twisted yarns formed around the outer periphery of a core consisting of ropes or braided braids made of twisted synthetic fibers. The net yarn ( The outer surface of the yarn is smoothed, which not only significantly suppresses the adhesion of sand mollusk spores and young molluscs, but also prevents intertwist defects between the yarns forming the core or between the strands even if they adhere to the core. Since the hollow parts and braided concave parts are covered with a cylindrical coating layer, it has been found that not only strong settlement (but also root expansion) is prevented. The inventors have come up with the idea of providing a net fabric that maintains its sexiness, and have already disclosed its contents in many prior applications.

By the way, net fabrics for fixed fishing nets and aquaculture fishing nets are required not only to have anti-algae and antifouling properties, but also to have strong knotting properties and resistance to currents and waves to prevent deformation such as mesh shifting during use. In this case, the mesh can be freely changed to reduce the resistance, or when the net is being hauled out, the net can be closed to reduce the bulk, making it easier to work on board. Stretchability for expansion, so-called network formation, and durability for long-term use are required as essential performances.

However, the net fabric based on the inventor's earlier application maintains knotty properties because the outer surface of the cylindrical coating layer formed around the outer periphery of the net yarn is made slippery in order to achieve algae- and stain-proofing properties. Furthermore, the twisted or braided unevenness of the core body is made to appear gently on the outer surface of the cylindrical coating layer, but in order to make this appear, the cylindrical coating layer must be made thin, i.e., as thin as possible. However, it had to be limited to approximately 700μ or less, and since it was required to have sufficient flexibility and elasticity as well as water resistance and weather resistance, thermoplastic synthetic resins, so-called plasticizers, were added. Polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, polyolefin/or a copolymer synthetic resin thereof is used. For the core, polyester or polyamide synthetic fibers with relatively high specific gravity and excellent toughness are used in order to maintain sufficient durability, so the core and the cylindrical coating layer are Since compatibility or heat-fusibility is not maintained over time, the back surface of the cylindrical coating layer is physically inserted into the inter-twist recesses or braid recesses formed on the core body. Because it is attached with
When the mesh is tightened together with the stretching heat treatment (heat setting) that follows the knitting of the mesh, the knots of the knotted knitted mesh fabric are bent, so the core body and the cylindrical shape are bent. There is a difference in the radius of curvature between the coating layer and the cylindrical coating layer, and there are parts where tensile force is applied and compressive force is applied in various places, and in such a state, a higher heat treatment temperature is required than with the cylindrical coating layer. Since the core is heat-treated, the cylindrical coating layer itself undergoes plastic deformation in response to the tensile and compressive forces, as well as uneven thickness and increased hardness. As a result, the back surface portion of the cylindrical coating layer, which is physically inserted into the knitted concave portion, is separated from the core body.

Although the material of the cylindrical coating layer has flexibility and elasticity, it is also brittle, inferior in toughness, and has a low coefficient of friction, which makes it difficult to contact with land surfaces, ship floors, etc. during net drying, laying, or removal work. Not only is it relatively easy to be damaged due to friction, or when excessive net lifting force is applied during net lifting work, or when net lifting force is applied locally, but the net thickness is approximately 700μ or less. Due to the combination of shearing and separation from the core due to heat setting, rupture and peeling are likely to occur, which not only causes a significant loss of product value, but also causes damage to the damaged parts and ruptured and peeled parts to be destroyed. There are problems with safety and durability, such as increasing the attached growth of sand shellfish.
This was a factor that hindered its spread.

The present invention provides a raw yarn for knitting fishing nets that solves this problem, and embodiments of the present invention will be described in detail below with reference to the drawings.

In the first figure, the core is a rope and the core is twisted on the outer surface of the cylindrical coating layer.
FIG. 2 is a detailed explanatory view of the present invention in which the core body is a rope and the outer surface of the cylindrical coating layer is smooth, and the core body (1) is The basic performance of the present invention is particularly related to strength, elongation, knot strength, elastic fatigue, etc., so the net is sufficiently strong, loose and knitted so that it does not blow away or develop poorly in the sea. Polyester or polyamide synthetic fibers (IA) are selected because a material with relatively high specific gravity is required to maintain the structure. A required number of these polyester or polyamide synthetic fibers (IA) are twisted to form a strand (IB) having a predetermined diameter. The core body (1) is formed by twisting two to four of these strands (IB) together to form a rope, but when the strands (IB) are twisted, the core body (1) Twisting at a pitch interval that is 25 to 50 times the diameter of the core body (1) results in the formation of thick twist unevenness on the surface Wj of the core body (1), which results in the formation of a cylindrical coating layer. This is advantageous in terms of improving the physical adhesion and the appearance of twist patterns on the outer surface of the cylindrical coating layer. The thermal core (1) is not limited to a rope, but can also be used as a braided braid of strands (IB), but in this case, the strands (IB) are It is desirable to configure the braid density to be relatively coarse, from the viewpoint of physical adhesion to the cylindrical coating layer and appearance of braid irregularities.

The outer periphery of the core body (1) thus formed has a hardness of JI.
It is made of a polyurethane-polyether copolymer resin with an S-A value in the range of 70 to 90, and has a thickness corresponding to 5 to 20% of the diameter of the core (1), and has a core (1) on its outer surface.
A cylindrical covering layer (2) in which the twist unevenness or braided unevenness of 1) is gently exposed is formed (/-).In other words, this cylindrical covering layer (2) is In the stretching heat treatment (mesh tightening and heat setting), the entire core (1) is made of polyester or polyamide synthetic fiber (L
A) Thermal energy from the heat source is transmitted or propagated to the extent that the material can be sufficiently heat-treated. Abrasion resistance and toughness that can sufficiently withstand strong friction and impact during drying work, installation and removal work, etc., or flexibility and elasticity that can sufficiently adapt to differences in the radius of curvature due to the curvature of the knot part, etc. are essential. The material with this performance is limited to polyurethane resin, but the results of a practical test using a net fabric knitted from raw threads with a cylindrical coating layer formed from the polyurethane resin. In this case, the polyurethane resin undergoes hydrolysis in the sea for a short period of time, and the outer surface of the cylindrical coating layer loses its lubricity and cracks occur, resulting in a significant decrease in algae and stain resistance, and furthermore, the abrasion resistance deteriorates. We came to the conclusion that the practical performance could not be maintained, as the properties and toughness deteriorated to "1". Therefore, we replaced the active groups involved in the hydrolysis of the polyurethane resin with inactive groups, and further improved various performances. In order to achieve this, by copolymerizing polyether with polyurethane, it prevents hydrolysis, and further strengthens abrasion resistance, heat resistance, and toughness without impairing flexibility, and also imparts excellent water repellency. This led to the selection of polyurethane-polyether copolymer resin.Although the hardness of this polyurethane-polyether copolymer resin varies considerably depending on the degree of polymerization, its performance also varies widely. If the hardness is less than 70 in JIS-A value, it becomes extremely soft and the coefficient of friction increases, creating tackiness, making it impossible to knit the net, and the hardness increases. If the hardness exceeds 90, the stiffness will increase significantly and the flexibility of the fabric will be impaired.
It is important to use a range of 70 to 90 in S-A.

The net thread used in fixed fishing nets, aquaculture fishing nets, etc., ranges from approximately 1 mm in diameter for thin ones to 8 to 10 mm for thick ones.
Over the wide yoke area up to the body φ, the net fabric is naturally knitted with thick yarns and is used in places where strong external forces such as tidal current resistance and wave resistance are applied, and the net fabric is also multilayered. Therefore, it is preferable that the thickness of the cylindrical coating layer (2) is determined in accordance with the diameter of the net yarn (original yarn), but at least the thickness is equal to that of the core. 5 of the diameter of (1)
% or more is required in order to prevent wear and tear due to friction and impact, and to prevent bursting and peeling, and it is desirable that the amount does not exceed at most 20 times the core diameter. This means that when the diameter of the core is 20% or more, the cross-sectional area of the cylindrical coating layer (2) becomes larger than the cross-sectional area of the core (1), which is responsible for the basic performance of strength, elongation, and knot strength. This results in a relative decrease in the proportion of the core body (1), which not only results in a mesh yarn (original yarn) that is inferior in toughness, but also reduces the flexibility, flexibility, etc. held by the twisted core body (1). It should be noted that there are consequences. The cylindrical coating layer (2) is formed by melt-coating polyurethane-polyether copolymer resin as a thermoplastic elastomer to the outer periphery of the core body (1) to a desired thickness using an extruder. Alternatively, a film of the required thickness is formed by dipping and passing through a polyurethane-polyether copolymer resin solution dissolved in a solvent, and then this is dried and solidified, or by dipping and passing again in a curing agent solution. A chemical reaction solidification method may also be used. In this case, the cylindrical coating layer (2)
If the cumulative hardness is in the range equivalent to JIS-A value 80 to 90, the rigidity and surface smoothness will be large, so the thickness is thinner and the core body (1) is formed in order to maintain nodularity. It is desirable to form the twisted or braided unevenness so that it appears gently on the outer surface, but if the cumulative hardness is in the JIS-A value range of 70 to 80, the friction coefficient will increase and Coupled with the tackiness of the material, the knotty property is sufficiently maintained, so there is no need to intentionally create unevenness in the twisted stitches or unevenness in the braid.

The present invention has the above-mentioned structure, and the core is made of strands made of twisted polyester or polyamide synthetic fibers, and the ropes are twisted at a pitch interval of 25 to 560 times the diameter. Alternatively, the strands are braided in 8 or 16 strokes, and the cylindrical coating layer is formed by melt coating or solution coating using a polyurethane-polyether copolymer resin, so that the back surface of the cylindrical coating layer is Physical adhesion is achieved by fitting into the inter-twist recesses or braid recesses of the core, and so-called chemical adhesion such as fusion or adhesion between the core and the cylindrical coating layer is also achieved. Because of this, the core body and the cylindrical coating layer are firmly attached, and the polyurethane-polyether copolymer resin that is the material of the cylindrical coating layer has high abrasion resistance and high elastic recovery rate. It also has a toughness that is 4 to 5 times higher than thermoplastic resins such as polyvinyl chloride resin, polyvinyl acetate resin, and polyolefin resin, and its softening point is approximately 140 degrees higher. In particular, the difference in the radius of curvature between the core body of the knotted part and the cylindrical covering layer during knotted knitting can be easily absorbed with its excellent elastic recovery rate. - Even during the heat treatment, the cylindrical coating N maintains its thermal stability and strong adhesion even when heat energy is applied to the core at ~120°C. As a result, separation from the core is completely prevented, and sufficient network lines and heat treatment can be safely performed.On the other hand, the net fabric that has been knitted and stretched and heat treated in this way has a smooth outer surface due to the cylindrical coating layer. Not only does the water repellency of the cylindrical coating combine with the water repellency to exhibit remarkable anti-algae and antifouling properties, but also the cylindrical coating layer's cylindrical properties and strong adhesion to the core body are combined. This prevents damage, abrasion, bursting, and peeling even when subjected to strong friction and impact during net lifting work, net drying work, hoisting, and removal work, and also prevents hydrolysis during underwater use. Therefore, the lubricity and water repellency of the outer surface of the net yarn are permanently maintained, and excellent algae and stain resistance as well as durability in use are exhibited over a long period of time. By forming the cylindrical coating layer using a polyurethane-polyether copolymer resin with a hardness of about 70 to 80, the outer surface of the cylindrical coating layer is made smooth because the friction coefficient increases and tackiness is exhibited. Excellent knotability is maintained even when formed into a net, and the cross-sectional shape of the net yarn is also approximately circular, which further reduces running water resistance. It is a raw yarn for knitting fishing nets that has many features such as being able to knit fishnet fabrics.

Experimental example Polyester multifilament 1000D//250
It can be seen that the F treatment causes a large number of separations and ruptures of RW, particularly in the nodule portion, and is therefore impractical. Furthermore, it is clear from Table 2 that the net yarn made from the raw yarn for knitting fishing nets of the present invention has much better abrasion resistance than the commonly used net yarn made from uncoated rope. Compared to netting made from uncoated rope, netting with a cylindrical coating layer has higher algae and stain resistance.
In particular, it can be seen that in the net fabric according to the present invention, after a certain degree of adhesion is achieved due to the lubricity and water repellency of the outer surface of the net yarn, natural detachment occurs due to the tidal current. The rapid increase in the amount of adhesion on polyethylene-coated or polyvinyl chloride-coated nets after three months is due to a decrease in the lubricity of the outer surface of the cylindrical coating layer due to deterioration due to seawater or sunlight or volatilization of plastic flow. This is thought to be due to the formation of pores.

[Brief explanation of the drawing]

Figure 1 is a detailed explanatory diagram of the present invention in which the core is a rope and convexities between the strands of the core are exposed on the outer surface of the cylindrical coating layer, and Figure 2 is a detailed illustration of the present invention in which the core is a rope and the convexity between the strands of the core is exposed on the outer surface of the cylindrical coating layer. Explanation of the symbols that are detailed explanatory drawings of the present invention with smooth surfaces (1)...Core (IA)...Polyester-based or polyamide-based synthetic fiber (A)... ...Strand (2) ......Tubular coating layer patent applicant Tokutabe Komuro

Claims (1)

[Claims] ■ A rope made by twisting strands made of polyester or polyamide synthetic fibers with a pinch interval of 2.5 to 50 times the diameter, or the strands are twisted in 8 or 16 strokes. The outer periphery of the core body, which is a braided braid, has a hardness of 70 to 70 in JIS-A value.
It is made of polyurethane-polyether copolymer resin in the range of 90% and has a thickness corresponding to 5 to 20% of the core diameter, and the twisted or braided irregularities formed on the core are the outer surface KM. A raw yarn for knitting fishing nets, characterized in that an fc cylindrical coating layer is formed to make crabs appear. ■Fishing net knitting yarn 0 according to claim 1, characterized in that the outer surface of the cylindrical coating layer is smooth.