JPH08112376A - Racket gut - Google Patents

Abstract

PURPOSE: To provide gut for rackets which has a good ball hitting feel and is highly strong, inexpensive and durable without adopting a Yarn winding structure by incorporating persimmon tannin or tannin component into a polyamicle based synthetic fiber filament. CONSTITUTION: This gut for rackets is formed by incorporating the synthetic fiber filament. Since the monofilament gut is simple in structure, the inexpensive gut having the high durability at the time of actual use is obtd. Impartation of waterproofness on the tennis gut is similarly expected as in the case fishing nets are treated with the persimmon tannin. Changing of the sectional shape is easy. Impact controllability and an effect of preventing the friction breakage of the gut by controlling the mutual slip of the guts are attained by forming the gut to a polygonal shape in section.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inexpensive racket gut for tennis, etc., which is excellent in water resistance and durability.

[0002]

2. Description of the Related Art As a racket gut used for tennis, badminton, squash and the like, sheep or cow intestine (natural gut) which is an animal fiber has been used. However, synthetic fibers such as nylon have appeared and have rapidly spread because of their excellent toughness and durability.

Synthetic fiber gut is not only excellent in the characteristics of the synthetic fiber material, but is further excellent in that the structure of the fiber can be modified. In recent years, with the sophistication of the technique of the ball game itself and its widespread use in the general public, the required characteristics in terms of competition have become diversified. Therefore, not only the material of the gut has been improved but also the fiber structure has been improved.

In particular, recently, with the widespread use of large rackets, the speed of competition has increased, and the conventional gut has a poor wind-cutting property, and it has become impossible to cope with the speed, and a fine gauge gut has been required.

To meet this demand, Japanese Patent Publication No. 2-28
By adopting a structure in which a winding yarn is wound around a core yarn as described in Japanese Patent No. 989, even if the thickness of the gut becomes thin,
A technique that does not decrease the strength, particularly the knot breaking strength, has been generalized.

However, this method makes the process of manufacturing the gut very complicated, resulting in an expensive gut.
Further, there is a drawback that the adhesive portion between the core yarn and the wound yarn becomes weak due to repeated impacts, exposure to sunlight, temperature change, humidity change, etc., resulting in poor durability.

In order to solve the above-mentioned problems of the prior art, the present invention improves the knot breaking strength with a monofilament without taking a wound structure, has a good shot feeling, is also strong in strength, inexpensive and durable. The purpose is to provide a good gut.

[0008]

In order to achieve the above object, the racket gut of the present invention comprises a polyamide synthetic fiber filament, and the filament contains a persimmon astringent or tannin component. Regarding gut.

Kakishibu generally gives a waterproof effect, gloss,
It is used for treating the surface of fishing nets, umbrellas, etc. for the purpose of improving gloss and making it less likely to be scratched and improving durability. The present inventors have diligently studied whether such properties can be applied to a racket gut, and a gut having high knot breaking strength, good shot feeling, high strength, and good durability can be obtained. It became clear and came to the present invention.

Kakishibu is a natural product and is obtained by crushing and squeezing shibu persimmon. Its composition is complex.
Known ingredients include sugars, ethanol, acetic acid,
For example, persimmon tannins. The persimmon astringent tannin component contained in this is considered to play a particularly important role. The persimmon astringent tannin component belongs to condensed tannins and has an average composition of C _76.
H ₅₂ O ₄₆ , which produces phloroglucin and gallic acid upon decomposition with alkali and zinc powder.

The same effect can be obtained by using a tannin component similar to this. Tannin components are widely present in the plant kingdom, and are contained in the bark and fruits of plants. It dissolves well in water, and the aqueous solution has strong absorptivity and has the property of transforming leather into leather. The tannin component is a general term for substances that generate polyhydric phenolic acid by hydrolysis and is not a constant compound. With a molecular weight of about 600 to 2000, polyoxyphenyl as the basic structure, and alkali decomposition yields phenols and phenolcarboxylic acids. The tannin components are roughly classified into pyrogallol tannin which produces pyrogallol and potassium catechol tannin which produces catechol by melting potassium. Further, it is classified into a hydrolyzable tannin which is hydrolyzed to produce gallic acid, ellagic acid and the like when heated with a dilute acid, and a condensed tannin which is polymerized to produce flovaphene insoluble in water. It is considered that the hydrolyzable tannin is one in which gallic acid, polyoxydiphenic acid, etc. are depside-bonded with sugar, and the condensed tannin is one in which several molecules of catechin, leucoanthocyan, etc. are polymerized.

The method of incorporating a persimmon astringent or tannin component into nylon is not particularly limited, but the following method is generally considered. A method of dissolving persimmon astringent in water or another solvent and immersing nylon gut in this solution. For example, a method in which nylon and persimmon astringent are melt-kneaded in advance and then molded into a nylon gut. The tannin component can also be contained by the same method. For example, when gut is dipped in persimmon astringent solution, persimmon astringent is impregnated into the surface layer part having a certain thickness of gut depending on the soaking condition, and the center part has a structure that is not affected, resulting in nodule fracture. A product excellent in strength, shot feeling, and durability can be obtained. This method is particularly suitable for a monofilament in the sense that it can impart to the monofilament a property that can counter the gut having a wound structure, but is also effective for a gut having a wound structure or a multifilament.

Compared with the conventional gut having a wound yarn structure, since the core yarn and the wound yarn are adhered by an adhesive in the wound yarn structure, the core yarn and the wound yarn are easily separated by repeated impacts. , There is a problem with durability. Furthermore, the wound yarn structure is expensive because the manufacturing method is complicated. Further, with the development of today's rackets, there is a demand for a fine gauge gut. To meet this demand, the method of the present invention is simple, but the wound structure is technically difficult.

The nylon monofilament gut obtained by the above-mentioned method has a simple structure, so that it is inexpensive and has high durability in actual use. In addition, it is expected that the tennis gut will be waterproof as in the case of persimmon astringent treatment on the fishing net.

It is also easy to change the cross-sectional shape, and by providing a polygonal cross-sectional shape, it is possible to give an effect such as striking controllability and prevention of friction cutting of the gut by controlling the slip between the guts. You can

[0016]

EXAMPLES The present invention will be described more specifically below with reference to examples. Table 1 summarizes the characteristics of Examples and Comparative Examples. In addition, each physical property shown in the following Examples and Comparative Examples was measured by the following test methods. (1) Tensile strength, elongation: JIS L1070 (2) Knot tensile strength: JIS L1070 (3) Hardness: Rockwell hardness, R scale ASTM
D-785 (4) Gloss: Deflection Gloss Meter ASTM D-523 (5) Sliding test: As shown in FIG. 1, the end of the gut is fixed at a position 183 cm away from the column and pulled diagonally upward to the column. A ring with a diameter of 5 cm made using the same 30 cm of gut is hooked on this gut. Then, the end of the gut pulled obliquely was gradually raised, and the position of the end of the gut pulled when the ring started to slide was measured.

Comparative Example 1 A 1.3 mm diameter nylon monofilament was molded for a tennis gut.

Examples 1 to 3 The monofilaments of Comparative Example 1 were immersed in an aqueous solution of persimmon astringency at 80 ° C. for the time shown in the table, washed with water and dried. When the knot breaking strength, breaking stress, and breaking elongation of the above samples were measured, the knot breaking stress became stronger as the persimmon astringent treatment time became longer. The straight line breaking stress and breaking elongation did not change so much, and when actually used as a tennis gut, the sample of Example 2 had the best shot feeling. Thus, it is also an advantage of this method that a gut having a different shot feeling can be obtained only by changing the persimmon astringent processing time.

The gut treated with persimmon astringent had a higher surface hardness than the gut not treated. This is the reason why the shot feeling is improved. Furthermore, the increased surface hardness makes it less likely to be scratched and improves the durability as a gut. The persimmon astringent treatment also improved gloss and slipperiness. The glossiness improves the appearance, and the increased slipperiness improves the operability when the gut is stretched on the racket.

With respect to racket gut other than the tennis gut, a good gut can be easily obtained by changing the persimmon astringent treatment time according to the change in the diameter of the monofilament.

[0021]

[Table 1]

[0022]

As described above, according to the present invention, it is possible to provide a gut which can increase the knot breaking strength by an inexpensive method, has high durability, and has a good shot feeling.

[Brief description of drawings]

FIG. 1 shows a measuring method for a slip test of the present invention.

Claims (1)

[Claims] 1. A racket gut comprising a polyamide synthetic fiber filament containing persimmon astringent or tannin components.