JPH04240233A - Production of spun yarn of double layer structure having stertchability - Google Patents

Abstract

PURPOSE:To produce spun yarn of double layer structure, having high stretchability, excellent water vapor absorption and water absorption properties which have never existed, soft handle and stretchability with a volume feeling. CONSTITUTION:Spun yarn of double layer structure consisting of 40-50wt.% core part of synthetic fiber stable and 60-50wt.% sheath part of natural fiber is arranged and twisted to give two ply yarns. Then the two ply yarns are subjected to false twisting processing in 2,000-3,000 times/m number of false twisting in the opposite direction of the twisting of the two ply yarns and then treated with hot water.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a stretchable two-layer spun yarn.

0002

BACKGROUND OF THE INVENTION Conventionally, as a yarn having elasticity, there is a stretch yarn made by subjecting long fibers (filaments) to a false twisting process.

[0003] In addition, this type of spun yarn includes long and short composite core yarns, which have a core made of a stretchable filament such as polyurethane and whose outer periphery is covered (covered) with natural fibers such as cotton or synthetic fiber staples. There is.

0004

[Problem to be Solved by the Invention] However, the former is made of false-twisted filament yarn made by false-twisting the filaments, and therefore, fabrics made using this yarn are naturally synthetic fibers. 100%, poor hygroscopicity,
Moreover, it is not possible to create a soft and voluminous fabric unique to natural fibers.

In the latter case, in order to solve the above-mentioned drawbacks of filaments, a stretchable filament is used as a core in the spinning process, and this is coated with natural fibers such as cotton. There was a problem in that the filaments were not easy to handle, and production control in the spinning process took time and effort, resulting in high costs.

[0006]Furthermore, the fabric produced using such a core yarn has properties similar to those produced using stretch yarn in which the filaments are subjected to a false twisting process.
It was only possible to obtain a paper-like fabric, and it was not possible to obtain an elastic material with a sense of volume.

[0007]

[Means for Solving the Problems] In view of the current situation, the method for producing a stretchable two-layer spun yarn of the present invention uses 40 to 50% by weight of synthetic fiber staples in the core and 60 to 60% by weight of natural fibers in the sheath. A two-layer spun yarn consisting of 50% by weight was aligned and twisted to form a double yarn, and then false-twisted at a number of false twists of 2,000 to 3,000 times/m in the opposite direction to the twisting of the double yarn. After that, it is treated with hot water.

[0008]

[Function] The two-layered spun yarn in the present invention is a two-layered spun yarn using synthetic fiber staples in the core and natural fibers in the sheath.
Examples include the method for manufacturing a double layer yarn described in Japanese Patent No. 11775.

That is, a plurality of slivers are fed from the back roller of a roving frame into the same draft area of the roving frame at intervals, and after being drafted to a predetermined thickness, the slivers are passed through a flyer head to form the roving. When winding as a core, at least one sliver is used as a core, and in order to wind other slivers around the sliver, the sliver forming the core is fed to the outside of the draft area as seen from the flyer head, and the wound sliver is The sliver that is fed inside and forms the core has an angle θ of 0 to 0, which is the angle between the extension line of the sliver in the draft axis direction and the line connecting the nip point of the front roller of the sliver and the flyer head, projected onto a horizontal plane. 60° range and use fibers that make up the core sliver that have higher draft resistance than the fibers that make up the wrapped sliver, or spin the sliver that makes up the core at a slower speed than the wrapped sliver. By at least one of the following, the spinning force of the sliver forming the core is made higher than the spinning force of the wrapped sliver, so that the twist generated by the rotation of the flyer of the roving frame is concentratedly propagated to the sliver forming the core, There is no transmission of twist to the wrapped sliver, and the wrapped sliver is spun while being wound around the sliver forming the core in a state where the constituent fibers easily slip between each other to form a roving having a double fiber layer. Next, the roving is used for spinning.

[0010] The twist coefficient of the two-layer spun yarn is 4.0 to 4.5.
For example, the number of twists in case of number 36 is 930.
~1100 times/m, number of twists in case of 64th thread is 1250~
1450 times/m is desirable.

[0011] The weight ratio of the synthetic fiber staple in the core is 4.
It is necessary to use it in a limited amount of 0 to 50% by weight. If the amount of synthetic fiber staples in the core is less than 40% by weight, the proportion of synthetic fiber staples is too small even if false twisting is performed, and the twisted shape memory due to false twisting is weak, making it impossible to develop stretchability. In addition, when the amount of synthetic fiber staples in the core exceeds 50% by weight, the amount of synthetic fiber staples is sufficient and the twisted shape memory can be developed without any problem by false twisting, but the amount of natural fibers in the sheath is Because there is too little, it is not possible to obtain a sufficiently satisfactory coating and it is not possible to obtain a complete two-layer spun yarn.

[0012] Furthermore, it is necessary to twist a plurality of such two-layered spun yarns into a double-stranded yarn. If a single yarn is subjected to false twisting to the extent that it can exhibit stretchability, the yarn will slip through, making it impossible to perform the desired false twisting process. The number of twists in the combined twist is preferably 80 to 90% of the number of twists in the two-layered spun yarn. For example, in the case of number 36, the number of twists is 750 to 1000 times/m,
In the case of number 64, the number of twists is preferably 1000 to 1300 times/m.

[0013] Next, a false twisting process is performed, and this false twisting process involves using a spinner to give 2,000 to 3,000 degrees
The fibers are twisted 0 times/m, the thermoplastic fibers are heat-fixed using a heat plate, and the fibers are untwisted and spun. Overfeed rate 5-1
It is desirable that the yarn speed be 0% and the yarn speed be 20 to 30 m/min.

[0014] Hot water treatment after false twisting is performed at 90%
It is desirable to carry out the process at a temperature of 130°C to 130°C, and in the case of a high temperature of 100°C or higher, the process is carried out under pressure. The hot water treatment may be carried out by processing such as dyeing or steam treatment, or may be carried out after being made into a fabric. The hot water treatment increases crimp, making it bulky and highly elastic.

[0015]

[Example] Two-layer spun yarn with a ratio of 40% by weight of polyester short fiber staples in the core and 60% by weight of cotton in the sheath part (English cotton count) (left twist, number of twists: 1280 times/
m), the two obtained two-layered spun yarns were pulled together and twisted right-handed at a rate of 1160 times/m to form a double-threaded yarn (64/2). The spindle rotation speed is 60,000 rpm, and the number of false twists is 2,000 times/in the left twist direction.
False-twisting was performed under the following conditions: m, feed speed 30 m/min, overfeed rate 3%, and heat set temperature 230°C. Next, hot water processing was performed at 100° C. for 30 minutes. When the yarn physical properties of the obtained yarn were measured, the elongation rate after hot water treatment (
JIS L-1090 method) 28.2%, recovery rate (JI
SL-1090 method) An extremely good elasticity of 82.6% could be obtained.

When this yarn was knitted smoothly, the elongation rate in the weft direction (JIS L-1018 method) was 87.3%, and the recovery rate (JIS L-1018 method) was 78%.
%, we were able to obtain a fabric with unprecedented stretch and volume.

[0017]

Effects of the Invention As is clear from the above description, the present invention has high elasticity, high moisture absorption and water absorption, and a soft texture that is not found in conventional thermoplastic false twisted yarns. in,
It has become possible to provide a method for producing a stretchable two-layer spun yarn that has excellent practicality such as a voluminous feel.

Claims (1)

[Claims] [Claim 1] Core portion is synthetic fiber staple 40-50
A two-layer spun yarn whose sheath portion is made of 60 to 50% by weight of natural fibers is aligned and twisted to form a double yarn, and then false-twisted in the opposite direction to the twisting of the double yarn for a number of 2,000 to 3,000. times/m
1. A method for producing a stretchable two-layer spun yarn, which comprises false-twisting the yarn and then treating it with hot water.