JPS62133138A - String and its production - 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] 3. Revised version! Technical field of use The present invention can be used for tennis, badminton, etc. racket strings, fishing lines, archery strings, etc., and dormitory equipment strings. J
The present invention relates to a capable string and a method for manufacturing the same.

BACKGROUND OF THE INVENTION Strings used in tennis rackets, for example, have been around since the beginning of the year, and recently strings made of fiber polymers such as polyamide and polyester have become overwhelmingly popular. In addition, with the recent appearance of aramid fibers, the use of aramid fibers is being introduced, but since aramid 4Ifi is currently in the form of a multifilament, it is difficult to use aramid fibers of several hundred deniers or several T deniers and other lIfi. Attempts have been made to use a small portion of fibers by mixing and twisting them with molten threads of miscellaneous materials or by processing them with resin. Conventional products that do not use aramid mH are made by making the core thread a synthetic 4& miscellaneous multifilament or monofilament, and surrounding it with thin monofilaments each time in the form of a twisted thread.

Problems that the defense seeks to solve By the way, when aramid i-fibers are used as mentioned above, because the core yarn is surrounded by aramid fibers in the form of a twisted thread,
If nylon monofilament or the like is not mixed and twisted together, the adhesion between the winding threads or between the winding thread and the core thread will be poor, making it difficult to maintain the shape of the fiber itself and the finished string during use as a tennis racket string or the like. Although aramid fibers have outstanding fiber properties such as tensile strength and abrasion resistance, they have the disadvantage of poor adhesion.

Ru.

The present invention is intended to solve these problems, and aims to provide a string with excellent performance in each strength and a desired cross-sectional shape.

Means for solving the problem In order to solve this problem, the ring of the present invention is as follows.
It is made by covering and braiding aramid 1jifi multifilament on the surface of a monofilament core thread covered with a synthetic polymer material. In addition, the method for manufacturing the string of the present invention involves braiding aramid Il& [ multifilament around a monofilament core thread made of synthetic polymer wood, and then braiding a polymer material with a secondary transition temperature of 35°C to 85°C. Impregnated with a dilute solution dissolved in a solvent, then the secondary transition point is 35
It is coated with a polymer material at a temperature of ℃ to 85℃.

Effect: This configuration improves the cooperation and provides the desired cross-sectional shape compared to the prior art.

Embodiments Hereinafter, embodiments of the present invention will be explained based on the drawings. In the present invention, the multifilament 1 of the aramid fiber is not used as the core yarn 2 of the monofilament made of synthetic polymer such as nylon or polyester, as shown in FIG. By overlaying the adhesive solution on the surrounding area, the aramid fibers are braided in a ``heuchi'' or ``16-uchi'' pattern.
The adhesive 3 reaches the monofilament surface of the core yarn 2 while maintaining the performance of iPNL, and the adhesion between the aramid fiber layer impregnated and absorbed with the adhesive and the core yarn becomes good, and the core resists stress against the string. The thread and the four threads will exhibit their performance at the same time. However, a method in which aramid fibers are used in a state with poor adhesion, such as in the form of monofilament fibers, results in a decrease in fiber performance. When the adhesive and the aramid fibers are bonded, the adhesive 3 enters the gap between the multifilaments 1 of the aramid, creating an anchoring effect and improving the bonding effect. In this case, thermosetting resin is not used as the adhesive. If a thermosetting resin is used, the strength of the string will be significantly reduced due to a decrease in elasticity at the outer periphery of the string. Next, to describe the bonding method using the adhesive, first, the multifilament 1 of the aramid set is assembled around the core yarn 2, and then a polymeric material with a secondary transition point of 35°C to 85°C is dissolved in a solvent. The coating is then impregnated with a dilute solution of 35°C to 85°C, and then coated with a concentrated solution of a polymeric material having a secondary transition point of 35°C to 85°C. Note that instead of this coating, melt coating may be performed using an extruder. The reason for using the dilute solution as described above is to make it easier for the concentrated adhesive solution to permeate through the multifilament 1 made of aramid 11i, and to make it easier to penetrate between the core thread 2 and the multifilament 1 made of aramid 4M. This is to facilitate the formation of a middle molecular film that has a tangential effect. Furthermore, the linear elongation at break of the monofilament serving as the core thread 2 is 22% or less.

Next, specific examples of the present invention, conventional examples, and comparative examples will be described in detail.

Specific example (No. 1) Core yarn: Nylon monofilament with a diameter of 0.6011n, linear strength 22 kg, linear breakage strength 15% Braided yarn: Multifilament of aramid fiber miscellaneous 200 denier, 32 wood stroke A resin solution containing polyamide resin (
After impregnating with a resin content of 3%), heat drying, and then overlaying a solution with a resin content of 12% and drying to finish. Measurement of finished product: 1f11, diameter 1.031RI, linear strength 121
kg, elongation 10%, and knot strength 611U.

0 Conventional example (No. 2) The core yarn uses nylon monofilament 0.8nua, and the winding yarn uses nylon monofilament 0.1611u+
use. This winding thread is upper and lower winding, 2 answers, 3 threads 1
It consisted of 40 pieces. The measurement value of the attached product is 1.42 in diameter
1Hn, straight line strength cuff 8kQ, elongation 32%, knot strength 4
It was 3 to 9.

O Comparative Example (No. 3) Aramid 1til [multifilament] fiber was made as a core thread and a winding thread. The core yarn used was one in which three fibers were twisted by mixing fused yarn into multifilamen 1-, which is an aramid fiber.

Also, the winding thread is 1) made of the same fiber as in item 0! The material is spirally wound once and a molten coating of polyamide is applied thereon. The diameter of the measuring pin for finished products is 1.25 nn.
Straight line strength 113kg, middle strength 8%, knot strength 48k (J
Met. The following table summarizes the measured values of the shell shell examples, conventional examples, and comparative examples described above.

It appeared. As shown in FIG. 2, on the base plate 6 which has ridges 4 and protrusions 5 on the upper surface at appropriate intervals in the front and back, strings 7 are placed between the front and rear within the ridges 4 and the ridges 5. 1
Install one. The sample strings 8 are placed under the strings 7 located in the Ichiki Man 4, and the sample strings 8 are placed so as to cover each string 7 orthogonally. Let it pass above. The difference in height between the bottom of Ichikiman 4 and the top of protrusion 5 is 511
1, and the stretched length of the string 7 is 20c. The tension of each of the strings 7 was adjusted using a weight shaft or the like using a 70% bond, and a 3K weight 9 was attached to one end of the sample string 8 to apply a load, and the other end was attached to an arm with a motor 10. 11 are connected with a counter 12 interposed in the middle. In this state, the arm 11 is rotated by the motor 10 at a rate of once/second, and the sample string 8 is repeatedly pulled at an amplitude of 20α. In this way, the thimble string 8 and the string 7 are caused to rub against each other, and the number of times the string 7 is pulled when even one string 7 breaks is read.

By the way, the reason why the linear breaking elongation of the core yarn 2 is set to 22% or less will be explained.

Conventionally, when the stretching ratio is increased in the production of core yarn, the linear break elongation gradually decreases, and the linear break cooperation improves, but the knot cooperation decreases from a certain point. For this reason, in the past, the straight line break elongation was about 23 to 27%, which was a good balance between the straight line break strength and the knot break strength. In the embodiments of the present invention, since aramid fibers with low linear break elongation are used as the outer yarn, the structure of the outer yarn is a braid with a relatively high elongation, and the core yarn has an elongation that matches the elongation of the outer yarn. The elongation is made smaller so that the closer one is better in terms of physical properties. If the difference in elongation between the core thread and the outer thread is too small, it is difficult to achieve both strength and the total strength is small, whereas it is easy to achieve strength when the middle 1'fffl is small. The core yarn used in the embodiments of the present invention has an elongation lower than that of conventional systems, that is, 22% or less. The material is made of 1J aramid fiber, which has a low elongation but has excellent linear strength and friction.

As described above, according to the present invention, the following effects can be obtained.

1) By braiding the multifilament of aramid Ill into the monofilament of the core yarn, it is possible to exhibit the high strength and high wear resistance that are the advantages of aramid fiber, without having to U-twist the other 41i wood.

2) If the core yarn or winding yarn of the string is aramid fiber yarn, the performance of the fiber will deteriorate due to warming with the rd-melted yarn in the process of making the yarn, twisting, resin processing, etc., and increase the cost. becomes. In the present invention, such a step is not necessary at all.

3) Il cost for braiding is based on conventional fiber usage J, Rimo F
XQ reserve costs will be significantly cheaper.

4) According to the present invention, the cross-sectional shape of the finished product can be any desired shape depending on the shape of the core yarn. If the shape of the monofilament of the core yarn is made into a circular, intrastate, or polygonal shape, and a multifilament of aramid fiber is added to the G fiber fEl, the multifilament is flexible, so it fits well into the core yarn.
-L: The shape of the core yarn is likely to appear. When aramid [ is used as a core yarn in a bundled system, the finished shape is difficult to form into a regular shape, that is, even if the finished cross-sectional shape is intended to be approximately circular, it will easily fit inside the shoe and it will be difficult to form a circular shape. Furthermore, when the fibers are stretched into a tennis racket, they tend to deform immediately.

5) In a string in which aramid fibers are covered and braided around a core thread, the intersection of the Ishinomaki or Maki braided threads forms a '21+ convex part. For example, when this string is strung on a tennis racket, due to the influence of this convex portion, it is difficult for the 1-point deviation to occur at the intersection of the diameter string and the $4-line when hitting the ball. In conventional monofilament mills or fibers wound around a core thread, the surface of the string is twisted in one direction, so if it is strung continuously on a racket, it will not be as strong when the ball is hit. Misalignment easily occurs, the batting force becomes uneven and irregular, and friction increases.

6) Mixing the molten yarn into the aramid core yarn as in the comparative example above makes the molten yarn part stronger in the melting process, and the viscosity of the molten substance is high, so
In the @warm process (the core yarn is thick, so the heat reaches the inside quickly), the adhesion is uneven and the strength is reduced, and there is almost no penetration of the molten material into the Aramid 41 filament, resulting in irregular molten resin. Adhesion causes uneven elongation, reduced strength, and shape deformation. In contrast, in the present invention, each powerful iJ3
It is also superior to comparative examples.

[Brief explanation of drawings]

FIG. 1 is an enlarged perspective view of a string in an embodiment of the present invention, and FIG. 2 is a perspective view showing a method of measuring frictional force. 1... Multifilament, 2... Core thread, 3...
Adhesive agent Yoshihiro Morimoto Diagram 1 procedural amendment (voluntary) January 24, 1985

Claims (1)

[Claims] 1. A string formed by covering and braiding a multifilament of aramid fiber on the surface of a monofilament core yarn made of synthetic polymer. 2. After braiding a multifilament of aramid fiber around a monofilament core thread made of synthetic polymer, impregnate it with a dilute solution of a polymer material with a secondary transition point of 35°C to 85°C dissolved in a solvent. , then the secondary transition point is 35℃ ~
A method for manufacturing strings that is coated with a polymeric material at 85°C.