JPS63126952A - Sheet like article for preventing cutting - 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 application field] The present invention relates to a sheet-like article for preventing biting off.

More specifically, the present invention relates to a bite-preventing sheet material used for raising underwater and terrestrial animals with sharp metal teeth such as pufferfish and rats, or for preventing damage caused by bites from these animals.

(Prior Art) Representative examples of fish with sharp gold teeth include blowfish, and representative examples of terrestrial animals include rats.

In recent years, the fisheries industry has been forced to shift from catching fish to growing fish due to the 200-yield problem, and aquaculture fisheries have been gaining momentum as a result of this. Demand and production (farming) of pufferfish, which is considered one of the fish dishes, are extremely active. Here, one of the important points for success or failure in aquaculture fishing is the rational and economical procurement of cage nets.
The fish cage net for pufferfish, which has two rows of sharp gold teeth on each side of the upper and lower sides, has seawater corrosion resistance and bite-proof properties in terms of durability, lightweight and flexibility in terms of ease of installation, and in terms of price. There has been a strong desire for the emergence of a net material that is both inexpensive.

Up until now, net materials for fish cages for cultivating puffer fish, which have the destructive power of crushing shellfish and regularly feed on shellfish, have been made with wires of about 8 to 12, with the primary purpose of avoiding damage caused by biting and escaping, which is the most feared by fish farmers. However, this method has various problems such as corrosion from seawater (rust), lack of chewing durability, and poor adhesion to complex submarine topography due to excessive weight and lack of flexibility. full of dots. Until now, attempts have been made to increase the diameter of the iron wire material used with the aim of improving the cutting durability, but although this method results in a slight extension of the cutting life, it has not been possible to improve the ease of laying. The reality is that various types of performance tend to deteriorate, and no drastic improvement measures have been found. In addition, general fishing nets made of aramid fibers have been proposed for the purpose of catching fish, but these nets are not intended to prevent animals with sharp gold teeth such as puffer fish from biting them. .

[Problem that the invention seeks to solve]

The present inventor aimed to develop a sheet-like material for preventing biting of puffer fish and rats, which fundamentally solves such technical problems.
As a result of intensive research on the Iflv cutting mechanism, we focused on the ultra-high tensile strength, ultra-high tensile modulus, and high cut resistance of aramid fiber multifilament yarn, and succeeded in improving the characteristics of the fiber yarn. This has led to the present invention. Therefore, the principle of the present invention can be effectively applied not only to blowfish but also to land animals such as rats.

The object of the present invention is to provide a sheet material for preventing chewing, which can solve all the problems of conventional iron nets, such as resistance to seawater corrosion, insufficient chewing durability, excessive weight, and lack of flexibility.

[Means for solving problems]

The present invention is a chewing prevention sheet made of aramid fiber multifilament yarn.

The aramid fiber referred to in the present invention is a general term for fully aromatic polyamide fiber, and is a highly crystalline and highly strong polyamide fiber, which includes polyparaphenylene terephthalamide, polymetaphenylene isophthalamide, polybenzamide, aromatic It refers to fibers made of polysulfide amide, aromatic polymethyleneamide, aromatic polysulfonamide, aromatic polyamine amide, aromatic polysulfite amide, etc. Due to its structural characteristics, it exhibits ultra-high strength and ultra-high elasticity, making it a fiber material with excellent mechanical properties and high specific strength, also known as super fiber. There are two types of aramid fibers based on their structure: meta-type and rose-type.
It is not a question of how. However, it goes without saying that in cases where mechanical properties, particularly high strength, are required, a bulk type is more preferable. Note that there is no question as to whether or not a different component is incorporated into the repeating structural unit.

In the present invention, multifilament yarn is a generic term for yarns that have two or more single fibers, and in aramid fibers that use wet spinning, the single fiber fineness is generally fine and is 1,500 denier. The most common type of filament is about 1.5 denier, as typified by 1.000 filament. There are some cases where the diameter is about 3 to 6 denier, and although this is not intended to be limiting in any way, the purpose of this is to avoid the stress concentration of the external force on the fiber material and to absorb and alleviate the generated stress into minute pieces. It is essential that the yarn be a multifilament yarn, and it is even more preferable that it be composed of a larger number of single fibers.

As mentioned in the section on problems with iron mesh, using monofilament is not suitable for this purpose.

Here, the aramid fiber multifilament yarn may be used as a net material using 100% aramid or blended with other fiber materials. In other words, the inflow of fresh seawater is blocked by the adhesion of algae, shellfish, etc.
From the viewpoint of preventing troubles such as an increase in the weight of the net, it is recommended to use copper wire or pre-rolled wire, which has the effect of dissolving copper ions and preventing the attachment of these marine animals and plants, and also because of its high heat resistance performance. Therefore, for the purpose of fixing the twisted yarn of aramid fibers, which cannot be heat-set, and preventing twisting of the mesh, and furthermore, to help prevent loosening of the knotted part in the Frogmata knotting method, the above-mentioned copper wire, pre-rolled wire, or pre-rolled wire is used. There are methods such as mixing ultra-rolled polyoxymethylene fibers with excellent moldability, and even mixing lead molded into a linear shape as a core material, and it is of course an effective means to use these alone or in combination as appropriate. In the case where the lead material is used in combination, the effect of improving the self-sedimentation property of the network can be expected at the same time. Further, by interposing a foamed rubber material with low elongation as a core material in combination with super-stretched polyoxymethylene fibers, the bite-off buffering effect can be further enhanced. In addition, we can fix twists, fix knots, and fix knots by heat-treating knitted nets using yarn dip-coated with low-melting point resins such as vinyl chloride and nylon-12 under tension.
It is also possible to simultaneously prevent the mesh from twisting.

6.Next, regarding the application of twist to the yarn, as one of the focusing means to make the aramid single fibers, which cannot be used practically with the absolute strength value of a single single fiber, exert the strength as a single fiber aggregate, It is very effective as a means for improving wear resistance and as a means for minimizing the distribution of stress generated by the helical structure effect against the external force of blowfish biting, and its use is extremely preferable.

In this case, the fineness of the thread, the twist composition, the number of twists, etc. should be determined by taking into consideration the species of fish, the size of the fish, etc., and are not limited in any way, but to give an example of a preferable range, the mesh The total fineness of the constituent yarns is 15.000
~30,000 denier, but in the case of the knotless knitting method, the twist structure is two lower twists (Z twists) and one upper twist (
If the configuration of S twist) is the Kajimata knot method, then lower twist (S twist) 3
A configuration with one main twist (Z twist) is preferable, and in the case of the Russell method, either type is acceptable.

However, in order to obtain the ultra-high tensile strength characteristic unique to aramid fibers in a network structure, it is necessary to completely avoid the low knot strength utilization rate common to aramid fibers and to use a knotless knitted network method that provides linear strength. Recruitment is most desirable.

Regarding the number of twists, the twist balance is within the range of first twist (130 to 170 T/M) and first twist (80 to 120 T/M).
It is preferable in terms of focusing effect, cutting-off buffering effect, abrasion resistance improvement effect, etc., but is not limited to this range.

As mentioned above, the effect of twisting is large, but there are other methods other than this method, such as braiding and knitting, which can similarly achieve a high buffering effect against external forces by biting, so manufacturing costs are also taken into account. It is preferable to select the

It goes without saying that when determining the mesh size, it is necessary to take into account the body size of the target fish.

In addition, the surface treatment of twisted yarns and braided yarns can be done as appropriate depending on the purpose of use, and coatings such as vinyl chloride, polyurethane resin, foamed polyurethane rubber, etc. are used mainly to improve weather resistance, which is one of the weak points of aramid fibers. Of course, it is effective to coat with the vinyl chloride polyurethane resin and polyolefin resin for the main purpose of improving wear resistance, and to coat with silicone or fluorine resin to prevent the adhesion of marine organisms. The foamed polyurethane rubber coating can further enhance the buffering effect against the external force of blowfish biting.

Furthermore, in order to improve the self-sedimenting properties of fish cage nets, high specific gravity lead can be blended in various shapes into the twisted system or braided cords, which eliminates the need to attach weights and makes it easier to use in the sea. A uniformly expanded state of the fish cage net can be obtained.

In the present invention, the sheet-like material for preventing biting off refers to a sheet-like material used for raising underwater and terrestrial animals with sharp gold teeth, such as puffer fish and rats, or for preventing damage from being bitten off by these animals. High cutting durability and flexibility are required.

Regarding the form of the sheet-like material, in the case of a seawater net for the purpose of rearing aquatic animals, a net-like structure is preferable so as not to obstruct the inflow of fresh seawater, and a sheet to prevent damage from biting off by terrestrial harmful animals is preferable. In this case, either a net-like structure or a woven or knitted structure may be used, and either one may be selected as appropriate. A representative example of an aquatic animal is a pufferfish, and a representative example of a harmful terrestrial animal is a rat.In these cases, the sheets must closely follow the contours of the object being protected, as they continue to bite and damage agricultural equipment. is desirable.

As detailed above, since the sheet-like product of the present invention is constructed using aramid fiber multifilament yarn as a base material, it is possible to blend other materials as necessary, apply appropriate twisting, or adopt a braided structure. By combining effective secondary processing such as various surface treatments, it becomes extremely effective in protecting against fish and terrestrial animals that have sharp gold teeth.

Here, the reason why sheets made of aramid fiber multifilament yarn exhibit superior bite-cutting durability compared to iron sheets is that in the case of iron sheets, the constituent material is a rigid and straight material made of a single wire. Because of this, the external forces of the animal's metal teeth are concentrated at one point on the material, and there is no place for the generated stress to escape, leading to material deformation or material failure, which easily causes material destruction. Promote further destruction. On the other hand, in the case of sheet-like products using aramid fiber multifilament yarn, the twisted or braided structure imparted to the component single fibers for the purpose of giving a moderate degree of freedom and cohesiveness has the ultra-high tensile strength inherent to aramid fibers. To make the fibers work effectively as a fiber aggregate, to improve wear resistance, to propagate the applied external meshing force, and to cause cross-sectional deformation of the twisted yarn in accordance with the applied external meshing force, making the point of action of the applied external force unclear; This is thought to be because the applied external force is dispersed and disappeared in multiple directions, and the biting force is absorbed and relaxed. Another great advantage is that there is no material corrosion.

Although multifilament yarns other than these, such as synthetic fibers and natural fibers, can be expected to have a multifilament effect, they cannot be compared with aramid fibers in terms of strength and cut resistance. Furthermore, the use of steel multifilaments has many problems such as rust and corrosion, excessive weight, and lack of flexibility, making it difficult to provide a solution.

Comparative evaluation of the ability to cut through the shochu between the aramid net of the present invention and a conventional iron net was carried out as follows.

The apparent thickness is roughly similar to that of steel No. 10, and it is a single thread equivalent to 27,000 denier rose aramid fiber.
■ Twisting: L500 denier/1, 000 filament of 6 filaments (S], 60T/M), , 3 twisted filaments (Z100T/M)). Model cutting test I was performed on the two freely released gauges using a sharp straight-edge bench using the midline push-cut method. Steel 1
No. 0 wire could be cut extremely easily! On the other hand, in the case of aramid fibers, in the former case, most of the child fibers were cut and the yarn was on the verge of breaking, and in the latter case, the single fibers forming the surface layer were cut. The fact that there was no damage can easily explain the fact that using aramid fiber with one thread of Multificimen has excellent bite resistance. In reality, the action of biting off a puffer fish is a rather complex movement (sliding), and it is easy to imagine that there will be a greater disparity than this.

In particular, the latter evaluation case is a test method that approximates the freedom of form when actually used as a net-like or woven or knitted structure, and it shows that aramid sheet-like products are practically superior. be.

Next, an outline of a method for manufacturing an underwater net using a knotless method will be explained. First, several loose aramid fiber multifilament yarns are twisted together, taking into consideration the target thickness.
Z twist). At this time, it is preferable to blend other materials and treat the surface as appropriate depending on the purpose, but in particular, it is necessary to prevent twisting of the atomized fiber mesh, which cannot be fixed by heat, fluffing, weather resistance (light) deterioration, and abrasion during knitting. From the standpoint of preventing this, it is extremely effective to apply a dipping process using vinyl chloride resin or the like. Next, the pre-twisted processed yarn is set in a knotless knitting machine and knitted while being twisted (S-twist) on the machine.

Finally, the knitted net is heated in a heat treatment machine in an expanded state, and the net is fixed by welding with a surface treatment agent to finish the net.

〔Example〕

Next, examples of the present invention will be specifically described in comparison with comparative examples.

Using the thread under the experimental conditions shown in Table 1, the mesh size was 8 cm (
4 cp per side) square mesh) The mesh was knitted using the knotless method using an underwater net for fish pens, and the mesh was chewed and damaged and corroded after 6 months of rearing puffer fish in the sea.・
We investigated its adhesion to complex seafloor topography.

The steel mesh was made using a general manufacturing method, and the aramid fiber was made from a loose material. The results are shown in Table 1.

(Here is a blank space) As is clear from Table 1, Examples 1 to 3 showed satisfactory results, showing excellent performance in terms of corrosion resistance and seabed adhesion in addition to high bite durability. Ta.

Among these, in Example 2, adhesion of algae and shellfish could be prevented at the same time. On the other hand, both Comparative Examples 1 and 2 had problematic results in terms of durability performance. As is clear from the results of this experiment, it is clear that a sheet with good chewing durability can be achieved by the present invention.

[Effects of the Invention] The anti-chewing sheet of the present invention is composed of aramid fiber multifilament yarn as a base material, thereby achieving both high chew-off durability and flexibility that were not available with conventional products. It satisfies the functionality. Because this sheet-like material has such excellent performance, it can be used in marine-related fields such as fish cages and fixed nets for cultivating fish with sharp gold teeth such as blowfish, sea breams, and moray eels, as well as agricultural equipment for land animals with sharp gold teeth such as rats. It can be used in a wide range of fields, including the prevention of damage caused by biting off of agricultural crops.

Claims (1)

[Claims] A sheet-like product made of aramid fiber multifilament yarn to prevent biting off.