JP2868639B2 - Modified nylon monofilament - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention can be obtained by mechanically melt-mixing different polymers and extruding them. It relates to a nylon monofilament having new properties.

[0002]

2. Description of the Related Art Conventional nylon monofilaments have the largest strength among engineered plastics in terms of strength, but have a large change with time due to water absorption and moisture absorption.
This is particularly noticeable when used for fishing lines. Further, the abrasion resistance was very strong in the vertical direction in which the amide bond was oriented, but was extremely low in the horizontal direction when formed into a monofilament. Naturally, this problem seems to be due to the hardness of the nylon. Therefore, when examining the material for each use of nylon monofilament, toothbrush bristles are made of nylon 612/610, tire cord is made of nylon 66, fishing line is made of nylon 6, or a copolymer thereof. However, the fishing line is generally subjected to a secondary processing for forming a film on the surface thereof and preventing a decrease in strength due to water absorption.

[0003]

The monofilaments made of nylon 610 and 612 are excellent in water absorption and abrasion resistance, are weak in tensile strength, and do not satisfy both physical properties. Nylon 66 is a material having high strength and excellent abrasion resistance, but has a large water absorption resistance and a long-term change associated therewith, and has a problem in moldability. Further, nylon 6 and its copolymer have a drawback that the strength is high but the water absorption resistance and abrasion resistance are not good. Considering the characteristics of each monofilament, as a result of examining to obtain a new nylon monofilament with its advantages on average,
The present invention has been completed.

[0004]

As a result of studying the above problems, the present invention provides a nylon monofilament having improved mechanical properties such as water absorption resistance, abrasion resistance and high strength of nylon 6 or a copolymer thereof. It has been found that the problem can be solved by melting and mixing the polyacetal resin with a lubricant . That is,
The modified nylon monofilament of the present invention comprises a polyacetal resin based on ε-caproamide polymer (nylon 6) or a copolymer of ε-caproamide and another amide.
It is characterized by adding 0.2 to 1.0% by weight of silicone oil as a lubricant to a nylon / polyacetal component mixed at a weight ratio of 1010%, melting, kneading, extruding and then stretching in at least two steps.

[0005] Such a monofilament of the present invention comprises:
After extrusion by a usual spinning method, it can be produced by cooling, then drawing and heat setting. At that time,
The diameter of the monofilament can be arbitrarily selected depending on the hole diameter of the die. More specifically, the spun yarn is solidified in a cooling medium such as water at 0 to 60 ° C, stretched in an atmosphere at a steam temperature of 80 to 95 ° C, or in hot water at 85 to 100 ° C, and then The desired modified nylon monofilament can be obtained by stretching in a furnace at a gas atmosphere temperature of 120 to 250 ° C. again and, if necessary, fixing it under relaxation or tension.

[0006] The mixing ratio of the polyacetal resin of the modified nylon monofilament can be arbitrarily selected within a range of 1 to 10 wt%, but the optimum range is 2 to 5 wt% as a result of considering the balance with the strength. If the mixing amount of the polyacetal resin is 1 wt% or less, the effect of the modification does not appear,
If the content is 10% by weight or more, the yarn becomes cloudy and tends to become brittle, which is not preferable.

[0007]

This modified monofilament has high hardness,
Resistant to friction and shows low water absorption (wet). Hereinafter, the present invention will be further described with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist thereof.

[0008]

Example: ε-caproamide polymer or nylon copolymer (ε-caproamide 85%, hexamethylene adipamide
(15%) as a base component, mixed with 3 wt% of polyacetal having a specific gravity of 1.40, and added with 3 wt% of silicone oil. Using this mixed component, a monofilament was produced under the following conditions. That is, the mixed raw material was supplied to a hopper of a 35 m / m extruder, and the extruded spun yarn was cooled in a water bath at 40 ° C. installed at a position 10 cm immediately below the spinning outlet. Next, the spun yarn is steamed at a steam atmosphere temperature of 90 ° C. in a first-stage drawing tank.
The film was stretched at a stretch ratio of 3.2 to 3.8. However, if the stretching ratio is too high, cracks in the form of horizontal stripes tend to occur, so it is preferable to set the stretching ratio in the range of 3.4 to 3.6. Next, the film was stretched in a gas atmosphere at a dry heat temperature of 185 ° C. in a second stage stretching tank at a magnification of 1.6 to 2.4 times. However, if the stretching ratio is high, thread breakage occurs in the tank, so that a stretching ratio of preferably 1.8 to 2.2 times is preferred. Next, heat-fixed in a gas atmosphere at 170 ° C. to a diameter of 0.290 mm
Was obtained.

The properties of the monofilament thus manufactured were evaluated in the following manner. The other three types of monofilaments were also examined according to the same production method as described above except that the amounts of polyacetal and silicone oil added were changed.

[Table 1]

The test method is as follows. 1. Tension / knot (strength, elongation): Shimadzu Autograph S-50
0-D Average of 5 measurements 2. 2. Water absorption: Shimadzu Moisture Meter TV-250D Average value measured 5 times. Dry heat shrinkage: According to JIS-L-1013 B method. 4. Abrasion resistance (wear cutting test): Sandpaper on outer periphery
One end of the monofilament is fixed horizontally to the rotating roll having (# 600) 13 cm away, and one end of the monofilament is fixed to the other end of the monofilament rotating roll 15 cm downward, and a 100 g weight is attached to the other end. It was rotated at a speed and the number of revolutions when a cut occurred was measured.

[0011]

As described above, the modified nylon monofilament of the present invention has high strength, low water absorption and abrasion resistance, and is not limited to Tegs, but also includes toothbrush bristles, tire cords and the like. It is a wide and effective monofilament.

Claims (2)

(57) [Claims] 1. An ε-caproamide polymer or a copolymer of ε-caproamide and another amide, and a polyacetal resin
A modified nylon monofilament obtained by adding , a lubricant , melting, kneading, extruding, and drawing in at least two steps. 2. A mixture of polyacetal resin of 1 to 10% by weight.
And adding 0.2-1.0 wt% of silicone oil
Item 6. The modified nylon monofilament according to Item 1.