JP4092313B2 - Core yarn sewing thread for product dyeing - Google Patents

Description

The present invention relates to a core yarn sewing thread which is excellent in the followability of stretch fabric and can be dyed by product after sewing.

  Currently, sewing threads for dyeing products such as jeans are mainly made of cotton yarn for the part where the seam is visible from the outside (needle thread), and the core thread is polyester or nylon for the part not visible from the outside (bottom thread). And the core yarn using cotton is used for the sheath yarn.

  It is self-evident that the same cotton sewing thread is suitable for dyeing cotton products, but cotton sewing threads are inferior in tensile strength and seam durability to polyester sewing threads and nylon sewing threads.

  Recently, jeans having stretch properties have been infiltrated, but cotton sewing thread has a low cut elongation of 5 to 7% and lacks the ability to follow the stretch of the fabric, and is likely to cause seam cutting.

On the other hand, there are also yarns that have improved durability of the seam and followability of the fabric, such as a core yarn sewing thread consisting of a composite yarn in which a synthetic fiber filament is used as a core yarn, and short fibers such as cotton are wrapped around it. (For example, refer to Patent Document 1).
Japanese Patent Publication No.59-11694

  By the way, the core yarn sewing thread as shown in the above [Patent Document 1] has no problem with respect to the durability of the seam and the ability to follow the stretch of the fabric, but the covering of the core thread with cotton as the sheath thread is not perfect. When the product after sewing is dyed with a reactive dye or the like, there is a problem that the core yarn portion such as polyester or nylon is exposed without being dyed, and cannot be used for a portion visible from the outside.

  In addition, 100% cellulosic yarn such as rayon is also available on the market. These yarns can be dyed in the same way as cotton, and the tensile strength is slightly higher than that of 100% cotton. Is almost the same as cotton sewing thread and is not suitable for use in stretch fabrics.

  Accordingly, there is a demand for a sewing thread that can be dyed with a reactive dye or a direct dye and that has a high cut elongation, particularly as a sewing thread for product dyeing of stretch jeans.

As described above, the present invention is the core yarn by completely covered with a sheath yarn, without core yarn even if the product dyed is exposed white after sewing, and Shin cut of at least 15% or more because it is the core yarn It is an object of the present invention to provide a sewing thread for product dyeing that has a high degree of followability to the stretch of the stretch material.

  Here, the inventor is a core yarn processed by an innovative spinning machine “MURATA VORTEX SPINNER” (hereinafter referred to as MVS (trademark registration No. 2699249-2) innovative spinning machine) manufactured and sold by Murata Machinery Co., Ltd. Above all, paying attention to the high coverage of the core yarn by the sheath yarn, by setting the ratio of the sheath yarn to the whole yarn to a certain level or more, the core yarn polyester or nylon is almost completely covered, and product dyeing A single thread for sewing thread was produced in which the core thread was not exposed in white later.

Since the sewing thread using this single yarn is a core yarn, the cutting elongation is higher than that of cotton yarn, and the followability to the elongation of the seam is excellent.

That is, the present invention is a composite yarn having a pre-twisted synthetic fiber multifilament as a core yarn and a cellulosic fiber as a sheath yarn, and the weight ratio of the sheath yarn exceeds 70% and is 80% or less, It is a core yarn sewing thread for product dyeing having a cut elongation of 15% or more and capable of being dyed after sewing.

By exposing the cellulosic fiber of the sheath yarn to more than 70% by weight and not more than 80%, more preferably not less than 75% and not more than 80%, exposure of the core yarn during product dyeing can be suppressed. .

  According to the present invention, it is possible to provide a sewing thread that can cope with product dyeing on stretch jeans fabric and has excellent followability to stretch of the fabric.

Hereinafter, the present invention will be described in detail.
For the core yarn of the single sewing thread of the present invention, a polyester or nylon yarn having a fineness of 44 dtex or 167 dtex, a tensile strength of 4.0 gf / d or more, and a cut elongation of 15% or more is suitable.

  In order to suppress entanglement of the sheath yarn at the time of spinning in this core yarn, and to allow the elongation of the core yarn to contribute effectively to the elongation of the sewing thread, a twist of a twist coefficient of 2,000 to 12,000 is made in the S direction. Put in.

Using the core yarn and cellulose fiber sliver such as cotton or rayon, a single yarn is processed by an MVS (registered trademark) innovative spinning machine. At this time, the ratio of the sheath yarn to the whole exceeds 80 % and 80 %. % Or less, more preferably 75% or more and 80% or less.

When the sheath yarn ratio is 70% or less, the coating of the core yarn with the sheath yarn is incomplete, and the core yarn that is not dyed when the product is dyed after sewing is exposed in white, making it unsuitable as a product dyeing yarn.

  On the other hand, if it exceeds 80%, the advantage over cotton yarn is lost in terms of tensile strength and cut elongation.

  In order to improve the yarn tightening, the single yarn thus produced is additionally twisted in the S direction with a twisting factor of 0.2 to 3.0, and a plurality of yarns are combined to increase the number of additional twists by 1 to 3 times. Insert the twist in the Z direction.

  This twisted yarn is treated in a bath at 110 to 130 ° C. for 20 minutes to shrink the yarn and further increase the cut elongation.

  A thread oil agent is added to this thread and the product is wound around a corn bobbin.

  If the cotton fabric is dyed with reactive dyes after sewing with the sewing thread made in this way, the sewing thread that is sewn will be dyed in the same way as the fabric, and the core yarn will not be exposed in white, and as a sewing thread for product dyeing We can use enough.

  In addition, the tensile strength of this sewing thread is almost the same as that of a normal cotton sewing thread, the cutting elongation is higher than that of a normal cotton sewing thread, and the followability to the stretch of the fabric after sewing is high. .

  Hereinafter, the present invention will be specifically described with reference to examples.

  In addition, the measured value in an Example was obtained with the following method.

(1) Sewing thread fineness (dtex) and count (Ne)
A cocoon with a sample length of 90 m was collected using a normal measuring instrument, dried for a whole day and night in a desiccator, and then weighed and calculated.

(2) Sewing thread cutting elongation (%) and sewing thread tensile strength (N)
According to the tensile test described in JIS-L-2511, it measured 20 times using the Shimadzu autograph tensile tester, and the average value was taken out.

(3) Core Yarn Twist Coefficient About the twist coefficient of the core yarn, the twist coefficient (k) = twist number (T / m) × √ (denier number) was calculated.

(4) Single Yarn Twist Coefficient The single yarn twist coefficient was calculated by the twist coefficient (k) = twist number (T / inch) ÷ √ (English cotton count).

(5) Measured number of lower twists / number of upper twists Using a normal twisting machine, measure the average length by measuring 20 times each with a test length of 25 cm, with the lower twist being the untwisted twisting method and the upper twist being the untwisting method. did.

(6) Stitchability Sewing is performed using a JUKI book stitch sewing machine. T / C broad (# 4,000) 6-ply fabric with 4,500 rpm, sewing needle # 16, 12 stitch pitch / The length of 4 m was continuously sewed 3 times under the condition of 3 cm, and the width of the upper thread tension range that could be sewn was evaluated.

(7) Product dyeability Product dyeability is determined by overlapping two cotton cloths 30cm long and 5cm wide with a JUKI book stitch machine, dyeing it in dark blue with reactive dye, soaping, and exposing the core thread after drying. Judgment was made visually.

[Invention Example 1]
A 78 dtex polyester yarn with a 1,150 T / m twist in the S direction is used as the core yarn, and a cotton sliver (commercially preferred) is used as the sheath yarn. The winding direction is set to S, the core: sheath ratio is set to 20:80, and fine spinning is performed to obtain about 16th single yarn.

  Two 520 T / m additional twists in the S direction are aligned, and an upper twist of 560 T / m is applied in the Z direction.

  Next, this yarn is treated in a bath at 130 ° C. for 20 minutes, and then a sewing thread oil agent is added.

  Finally, the product is wound on a corn bobbin.

  In Example 1 of the present invention, the cut elongation is 17%, which is significantly higher than the normal cotton sewing thread elongation rate of 5-7%, and the followability to the seam elongation when the stretch material is sewn is high.

  As a result of the sewability test, although compared with # 30 of a normal cotton / polyester core yarn marketed, it was slightly inferior in the region where the upper thread tension was high, but could be sewed without any problem in the normal tension region.

  Further, as a result of dyeing with a reactive dye after sewing a cotton material using Example 1 of the present invention, exposure of the undyed core yarn was hardly recognized.

[Invention Example 2]
A 78 dtex nylon yarn twisted at 1,000 T / m in the S direction is used as the core yarn, a cotton sliver is used as the sheath yarn, and the winding direction is set to S by the MVS (registered trademark) innovative spinning machine. The sheath ratio is set to 25:75, and spinning is performed to obtain about 19th single yarn.

  Two of those twisted 180 T / m in the S direction are aligned, and an upper twist of 370 T / m is applied in the Z direction.

  Next, this yarn is softly wound and treated in a bath at 120 ° C. for 20 minutes, and then a sewing thread oil agent is added and wound around a corn bobbin.

  In Example 2 of the present invention, the cut elongation is as high as 19%, and the sewability and product dyeability are satisfactory.

[Invention Example 3]
Similarly, a nylon yarn (78 dtex, S direction: 1,000 T / m) is finely spun as a core yarn, subjected to additional twist 350 T / m, top twist 600 T / m, 120 ° C. × 20 minutes in a bath, A thread oil was added and wound around a corn bobbin.

  In Example 3 of the present invention, the cut elongation is 18%, and there is no problem with the sewing property and the product dyeability.

[ Comparative Example 1 ]
The same core yarn as in the present invention example 2 was used, and the core: sheath ratio was set to 30:70, which was finely spun. Hereinafter, the yarn processed under the same conditions as in the present invention example 2 was slightly dyed as a result of product dyeing An exposure of the core yarn was observed .

[ Comparative Example 2 ]
110 dtex nylon yarn heated to 800 T / m is used as the core yarn, and the core: sheath ratio is set to 35:65 to perform spinning. After twisting 180 T / m in the S direction, the two are aligned and aligned in the Z direction. A 370 T / m upper twist was added and treated in a bath.

The cut elongation of Comparative Example 2 was as high as 24%, and the followability to the elongation of the fabric was high. However, as a result of product dyeing, the core yarn was slightly exposed .

[Comparative Example 3]
110 dtex nylon yarn heated to 800 T / m is used as the core yarn, the core: sheath ratio is set to 40:60, spinning is performed, and after twisting 130 T / m in the S direction, the two are aligned and aligned in the Z direction. A 410 T / m upper twist was added and treated in a bath.

  The cut elongation of Comparative Example 3 was as high as 26%, but the result of product dyeing was unsuitable because the core yarn was exposed in white.

[Reference example]
In addition, a core yarn sewing yarn (Reference Example 1) spun using untwisted polyester as the core yarn and spun to a sheath yarn ratio of 38% using a normal ring spinning machine, and similarly untwisted nylon as the core yarn The characteristics of a core yarn sewing thread (Reference Example 2) that has been ring-spun so that the sheath yarn ratio is 45% and a 100% rayon span sewing thread (Reference Example 3) are shown as reference examples.

Claims (1)

A composite yarn having pre-twisted synthetic fiber multifilament as a core yarn and cellulosic fiber as a sheath yarn, the weight ratio of the sheath yarn is more than 70% and not more than 80%, and the cut elongation is 15%. Core yarn sewing thread for product dyeing that can be dyed after sewing.