JPH0382836A - Polyvinyl alcohol based spun yarn having excellent cut breakage resistance - Google Patents

Abstract

PURPOSE:To obtain the title spun yarn constituted of a specific high-strength polyvinyl alcohol based crimped fiber, being specific in tensile strength and cut breakage resistance and having high strength and excellent cut breakage resistance and useful for protective clothing. CONSTITUTION:The aimed spun yarn composed of high-strength polyvinyl alcohol being >=13g/d tensile strength of single fiber consisting of polyvinyl alcohol based polymer having >=1500 polymerization degree and satisfying the formula DX2<=L<=DX50 [L is average fiber length (mm); D is average single fiber fineness (d)] in average fiber length L (mm) and being >=5.0g/d in tensile strength DT of spun yarn and >=0.08g/d in cut breakage resistance C of spun yarn-diffraction method.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a polyvinyl alcohol-based spun yarn, and particularly to a spun yarn that has high strength and excellent cut resistance.

<Prior art> Regarding general-purpose fiber materials such as polyester and nylon, in the field of protective clothing such as protective gloves and protective aprons, the spun yarn count is reduced to increase the apparent bulk9.
Efforts have been made to improve cut resistance and avoid problems related to cut resistance by exploring measures such as increasing the number of yarns in 1 m of knitting yarn.

However, when the above-mentioned measures are adopted, the resulting protective clothing has a rough texture and is extremely uncomfortable to wear. or,
Problems such as insufficient cut resistance still remained.

Furthermore, conventional polyvinyl alcohol-based spun yarns have a low tensile strength of about 6 g/d. Therefore, the field of use of the spun yarn is mainly for clothing, and its use in industrial applications has been extremely limited.

Furthermore, cut resistance, which represents cut resistance, represents the difficulty of cutting with a knife, and if the cut resistance is small,
Cuts and puncture wounds are likely to occur when handling metal shavings, broken glass, bent metal sheets, etc., and when cutting meat using knives, etc., and the intended purpose of protective clothing and equipment is not met. Can not do it.

In the case of the polyvinyl alcohol-based spun yarn, the cut resistance is as low as about 0.05 g/d, and therefore, it has been difficult to apply it to protective clothing, protective gear, etc.

On the other hand, spun yarns of para-aramid fibers are known as high-strength spun yarns. Moreover, although the cut resistance of the spun yarn is approximately 0.1.8 g/d, which shows excellent performance, the spun yarn tensile strength is approximately Log/d.

Compared to the single yarn strength (approximately 22 g/d), it cannot be said that the strength is sufficiently reflected.

Furthermore, since para-aramid fibers are originally composed of rigid molecular chains, the single yarns are susceptible to damage such as buckling when crimped. Therefore, the quality of the spun yarn made of the crimped fibers is also poor. In addition, para-aramid fibers have poor light (climate) resistance, particularly UV resistance, and are unsuitable for applications where they are exposed to sunlight for long periods of time.

9. Protective gloves used outdoors, for example.

1 daylight exposure when used for protective clothing such as a protective apron.

In particular, there was a problem in that the performance deteriorated significantly due to ultraviolet rays.

Problems to be Solved by the Present Invention> The problem to be solved by the present invention is to achieve high strength by utilizing the characteristics of high-strength polyvinyl alcohol fibers.

Another object of the present invention is to provide a spun yarn with excellent cut resistance of 9 grades.

〈Means for solving problems〉 That is, the present invention has the following configuration.

A single filament made of a polyvinyl alcohol polymer with a degree of polymerization of 1500 or more and a tensile strength of 13 g/d or more.

Consisting of high-strength polyvinyl alcohol-based crimped fibers whose single yarn average fiber length L (m, m) satisfies the following formula (1),
A polyvinyl alcohol-based spun yarn having excellent cut resistance and having a spun yarn tensile strength DT of 5.0 g/d or more and a spun yarn cut resistance ΔC of 0.08 g/d or more.

D×12≦L≦DX50...(I)
L: Average fiber length (mm) D = Average single filament fineness (d) In other words, the polyvinyl alcohol polymer in the polyvinyl alcohol spun yarn of the present invention (hereinafter referred to as the spun yarn of the present invention) is a completely saponified straight yarn. It is desirable to have a chain shape, but a partially saponified type can also be used. The degree of polymerization is required to be at least 1,500, and if it is less than 1,500, fibers with high strength and high cut resistance cannot be obtained, and the spun yarn targeted by the present invention cannot be obtained. A preferable degree of polymerization is 1
500 to 10,000, particularly preferably 3,000
~5000. Generally, a high degree of polymerization makes it easier to obtain fibers with high strength, but a degree of polymerization of 10,000 or more is not preferable because manufacturing costs become a problem.

In addition, as a spinning method, the tow spinning method, that is, the parlock method and the staple spinning method, can be applied, but in particular,
The tow spinning method is preferable since it is easy to obtain a spun yarn with high strength and excellent cut resistance.

Furthermore, as the average fiber length of polyvinyl alcohol fibers (PVA fibers) increases, the tensile strength of the spun yarn increases, but the number of twists of the spun yarn decreases, resulting in a decrease in cut resistance. Therefore, the average fiber length of PVA-based fibers is D×12≦L from the viewpoint of the tensile strength, cut resistance, and spinnability of the spun yarn.
≦DX50 (L: average fiber length (mm), D: average single yarn fineness (d)), and the preferable average fiber length is D×20≦L
≦D×35.

In order to expand the application to industrial applications, the tensile strength DT (g/d) of the spun yarn, which has a large effect on the tear strength etc. of a woven fabric composed of spun yarn, should be 5°0≦DT, preferably 8 .0≦DT is required.

In addition, in order to expand the application to protective clothing such as protective gloves and aprons, it is required that the 9MA fabric made of spun yarn has excellent cut resistance.

Therefore, the cut resistance ΔC (g/d) of the spun yarn is 0°08
≦ΔC1, preferably 0.1≦ΔC should be maintained.

6- If this cutting resistance is less than 0.08 g/d.

The difficulty of cutting with a knife is reduced, and protective clothing and equipment used in the work can be easily torn by metal chips and glass fragments generated during lathe processing, etc.

As a result, they are susceptible to cuts, punctures, etc., and the intended purpose of protective clothing, protective gear, etc. cannot be fulfilled.

Here, the cut resistance of the spun yarn was determined by the following method.

That is, two sample spun yarns are held in parallel at the center of the frame with an interval of 1.0 mm so that the effective length is 5 mm, and an angle of 60° is formed between the two sample spun yarns. A steel blade with blades on two sides is placed vertically and applied, and the load weight at which the sample spun yarn is cut when a load is applied to the blade edge is measured.

Furthermore, the cut resistance of the spun yarn was obtained by dividing the measured load weight by the fineness of the sample spun yarn.

Note that the spun yarn of the present invention may be mixed with other organic fibers and inorganic fibers in any proportion as necessary.

Next, there is a PVA-based fiber that can meet the requirements of the present invention.

An example of manufacturing spun yarn will be explained.

That is, in the present invention, a spinning stock solution is obtained by dissolving a polyvinyl alcohol polymer having a degree of polymerization of 1500 or more in dimethyl sulfoxide as a solvent. The obtained stock solution is extruded through the nozzle discharge hole and subjected to dry-wet spinning in a coagulation medium made of methanol, and then washed in a methanol solution, bath-stretched, and dried in succession so that the effective total stretching ratio becomes 15 times or more. After heating and stretching, the fiber bundle temperature is 40°C or higher and 70'C.
After heating with hot water to achieve the following, crimps are applied using a crimping machine so as to have specified crimp characteristics, and substantial heat setting is performed at 80'C or less. Next, a predetermined spun yarn is obtained by a conventional spun spinning method.

By the above method, it becomes possible to obtain PVA-based fibers suitable for spun yarns that have high strength and excellent cut resistance.

The stretching conditions in this case are such that the effective total stretching ratio is 15 times or more. This effective total stretching ratio is 1
If it is less than 5 times, the target spun yarn physical properties, especially tensile strength DT
5.0 g/d or more cannot be obtained.

In addition, the preferred atmospheric temperature during stretching is 220
~260°C. By maintaining this temperature range, stretching at an effective total stretching ratio of 15 times or more can be more easily performed, and fibers with the desired high physical properties can be obtained.

As a method for heating the fiber bundle in hot water, any method can be used as long as the required temperature of the fiber bundle is obtained using substantially hot water, such as a hot water bath immersion method or a shower method. Of course, an oil agent or the like may also be mixed.

Furthermore, any method may be used for crimping as long as it does not substantially cause damage such as buckling to the fibers. Mechanical crimping using a push-in crimper is preferred.

After heat setting, the necessary finishing oil is added to improve the tensile strength and
From the viewpoint of cut resistance, the average fiber length of PVA fibers × 12≦L≦DX50 (L: average fiber length (mm), D
: Average single yarn fineness (d)), preferably DX20≦L≦D
Cut with a cutter 9-1 to obtain the required raw cotton so that it becomes ×35.

Here, the effective total stretching ratio is obtained by dividing the take-off speed after dry heat stretching by the take-off speed after exiting the coagulation bath.

Note that the spinning method may be any method used for producing high-strength polyvinyl alcohol fibers.

The effects of the present invention do not change depending on the dry method, wet method, dry-wet method, gel spinning method, etc. Further, the heating stretching method may be a liquid bath, warm heat, dry heat, hot plate, bottle, hot roller stretching, or the like. Furthermore, after heating and stretching, any heat treatment such as warm heat, dry heat, tightening, fixed length, or relaxation may be performed.

The finishing oil may be applied at any step after the dry heat stretching.

<Example> Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1 Raw yarn 1500D obtained by dry-wet spinning a spinning stock solution in which completely saponified polyvinyl alcohol with a degree of polymerization of 2600 was dissolved in a solvent, followed by washing, bath stretching, drying, and dry heat stretching. /600f (single yarn strength 20
g/d, elongation at break 4.6%) to make a 10°80,000 tow. 9 A 26th spun yarn with an average fiber length of 76 mm was obtained by a normal Parlock tow spinning method.

The tow cutability by the Purlock method was good, and there were no problems in passing through the spinning process.

Moreover, the obtained spun yarn was a good spun yarn without generation of neps or the like.

The strength of the spun yarn is 1349g (1N! 11 degrees 13.4g/
In d), the elongation at break was 7.2%.

On the other hand, the cut resistance of the obtained spun yarn was 0.1 g/d, and it was an excellent spun yarn with sufficient cut resistance for use in protective clothing.

Example 2 Raw yarn 1500D/600f was obtained by dry-wet spinning the same spinning dope as in Example 1 and under the same spinning and drawing conditions.
(single yarn strength 20 g/d, breaking elongation 4.6%) was combined to obtain 108,000 tows.

After applying mechanical crimp to the obtained tow under heating.

Cut it with a knife to 51mm length to make cotton for spinning.

A 20-count spun yarn was obtained by a normal staple spinning method.

The strength of the spun yarn is 2605g (strength 9.8g/d)
The elongation at break was 8.5%, and there was no decrease in strength due to one machine crimp. In addition, there were no miscuts due to deterioration in the sharpness of the knife, and the spun yarn was of good quality with no occurrence of neps or the like.

Moreover, the cut resistance of the obtained spun yarn was 0.11 g/d, and it was an excellent spun yarn with sufficient cut resistance for use in protective clothing.

Example 3 A raw yarn of 1.500D/400 was obtained by wet-dry spinning the same spinning solution as in Example ① and under the same spinning and drawing conditions.
f (single yarn strength 21.g/d, breaking elongation 488%) was combined to obtain 108,000 tows.

After applying mechanical crimp to the obtained tow under heating.

Cut it with a knife to 64mm length to make cotton for spinning.

A 20-count spun yarn was obtained by a normal staple spinning method.

The strength of the spun yarn is 2764g (strength 10.4g/d)
The elongation at break was 7.9%, and there was no decrease in strength due to the two-machine crimp. In addition, there were no miscuts due to deterioration in the sharpness of the knife, and the spun yarn was of good quality with no occurrence of neps or the like.

Furthermore, the cut resistance of the obtained spun yarn was 0.11 g/d, and it was an excellent spun yarn with sufficient cut resistance for use in protective clothing.

Comparative Example 1 Raw yarn 150 obtained by dry-wet spinning a spinning stock solution in which completely saponified polyvinyl alcohol with a degree of polymerization of 1000 is dissolved in a solvent, followed by washing, bath stretching, drying, and dry heat stretching.
0D/600f (single yarn strength 10.6 g/d, cutting elongation 3.2%) was doubled.

108,000 tows were obtained. The obtained tow was mechanically crimped and cut with a knife into 71.51 mm long pieces under heating to produce cotton for spinning, and a 20-count spun yarn was obtained by a normal cotton spinning method.

The strength of the spun yarn is 1197 g (strength 4.8 g/d) and the elongation at break is 4.8%, and the strength of the spun yarn is 1197 g (strength 4.8 g/d) and the elongation at break is 4.8%. low.

Furthermore, the cut resistance of the obtained spun yarn was as low as 0.04 g/d, which was insufficient for industrial use and protective clothing.

Comparative Example 2 Raw yarn 1500D/400f obtained by dry-wet spinning the same spinning dope as in Example 1 and under the same spinning and drawing conditions.
(single yarn strength 21 g/d, breaking elongation 4.8%),
108,000 tows were obtained.

After applying mechanical crimp to the obtained tow under heating.

Cut it with a knife to 38mm length to make cotton for spinning.

A 20-count spun yarn was obtained by a normal staple spinning method.

The strength of the spun yarn is 2020g (strength 7.6g/d)
The elongation at break was 5.2%, and a decrease in strength was observed due to insufficient entanglement due to the short average fiber length.

Furthermore, since the average fiber length was short, many of the fibers fell off during the spinning process, resulting in poor spinnability and a spun yarn of satisfactory quality could not be obtained.

In addition, the resulting spun yarn had a cut resistance of 0.06 g/d, which was insufficient for use in protective clothing.

Comparative Example 3 Raw yarn 1500D/400f obtained by dry-wet spinning the same spinning dope as in Example 1 and under the same spinning and drawing conditions.
(Single yarn strength: 21 g/d, breaking elongation: 4.8%) were combined to obtain 108,000 tows.

After applying mechanical crimp to the obtained tow under heating.

Cotton for spinning was prepared by cutting it into 200 mm lengths with a knife, and a 20-count spun yarn was obtained using a normal spun spinning method.

The strength of the spun yarn is 2340g (!J1 degree 8.8g/d
), the cutting elongation was 5.2%.

However, the resulting spun yarn had a cut resistance of 0.04 g/d, which was insufficient for use in protective clothing.

<Effects of the Invention> By using the polyvinyl alcohol-based spun yarn of the present invention, which has high strength and excellent cut resistance, it is possible to work with metal scraps, glass fragments, bent metal plates, etc., and use cutlery. It is possible to provide at low cost highly safe protective clothing, protective equipment, etc. suitable for work such as meat butchering work where there is a risk of incurring cuts, puncture wounds, etc.

Claims (1)

[Scope of Claims] High-strength polyvinyl made of a polyvinyl alcohol-based polymer having a degree of polymerization of 1500 or more and having a single yarn tensile strength of 13 g/d or more and a single yarn average fiber length L (mm) satisfying the following formula (I) It is composed of alcohol-based crimped fibers, has a spun yarn tensile strength DT of 5.0 g/d or more, and has a spun yarn cut resistance Δ.
A polyvinyl alcohol-based spun yarn with excellent cut resistance and a C of 0.08 g/d or more. D×12≦L≦D×50...(I) L: Average fiber length (mm) D: Average single yarn fineness (d)