JPH08199441A - Yarn used in sewing machine and its production - Google Patents

Abstract

PURPOSE: To provide a sewing machine yarn which has jointing points formed by fusing a thermally fusible spun yarn containing a specific amount of thermally fusible stable fibers with a high-melting filament yarn, is excellent in strength, untwisting resistance, high-speed sewability and fluffing resistance. CONSTITUTION: This sewing machine yarn comprises at least a thermally fusible spun yarn containing 20-100wt.% of thermally fusible staple fibers melting at 100-180 deg.C and a high-melting filament yarn melting over 200 deg.C, where they are fused to have jointing points. The jointing points fix the yarn twisting to prevent the sewing machine yarn from being untwisted when it is used in back sewing or zigzag sewing, whereby the sewability is increased, and fluffing is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sewing thread having excellent sewability.

[0002]

2. Description of the Related Art Conventionally, as a sewing thread, cotton,
Sewing threads such as silk and synthetic fibers are widely used,
In recent years, synthetic fiber sewing threads have been widely used from the viewpoints of strength and dyeing fastness. Especially, among synthetic fiber sewing threads, polyester filament sewing threads and polyester spun sewing threads have become the mainstream.

Polyester filament sewing threads are excellent in strength, but inferior in heat resistance and abrasion resistance.
There is a problem that the high-speed sewability is poor. On the other hand, the polyester spun sewing thread has excellent high-speed sewability because its fluff improves heat resistance and wear resistance, but it is inferior in strength, and the fluff comes off during sewing and There is a drawback that it adheres to the hook portion and the pressing portion of the sewing machine and contaminates the sewing cloth.

[0004] As a sewing thread which improves the defects of these polyester filament sewing thread and polyester spun sewing thread, for example, Japanese Patent Publication No. 62-38457 discloses a polyester filament as a core component and a polyester short fiber as a sheath component. A core yarn sewing thread has been proposed.

Although this sewing thread is excellent in strength and high-speed sewability, since it is a twisted sewing thread, it is sewn with a sewing machine needle or a sewing machine hook during back stitching, zigzag stitching and the like. There is a problem that the twist is untwisted and the sewing machine yarn is broken into single yarns, broken, and skipped, and the sewability is deteriorated.

In order to solve this problem, the sewing thread is coated or impregnated with an adhesive resin to prevent untwisting of the sewing thread. In this sewing thread, the adhesive resin is coated. In addition, the manufacturing cost is high because it requires a special device for impregnation and an extra step. Moreover, at the time of sewing, the sewing machine thread is squeezed by the sewing machine needle or the sewing machine hook, and the resin falls off, and the sewing machine There is a drawback that it adheres to the hook and the like and causes various sewing problems.

For the purpose of improving the drawbacks of the conventional twisted sewing thread, for example, JP-A-2-2694 is used.
Japanese Unexamined Patent Publication No. 4 (1994) proposes a sewing thread composed of a polyester filament or a polyester spun yarn and a low-melting thermoadhesive polyester multifilament, in which the thermoadhesive polyester filament is melt-bonded to fix the twist.

Although the untwisting resistance is certainly improved in this sewing thread, its effect is not sufficient because the heat-adhesive fibers are filaments, and the twisting is still performed during back stitching, zigzag stitching and the like. Is untwisted and the single thread of the sewing thread breaks,
When the polyester spun yarn is used, fluff is relatively frequently dropped off, and when the polyester filament is used, the high-speed sewability becomes inferior.

Further, JP-A-62-162039 comprises a blended yarn containing a low-melting point copolyester short fiber, which is melted or softened to increase rigidity. , A sewing thread that prevents the occurrence of skipped stitches is described, but since this sewing thread is composed only of spun yarn, it has low strength and is also used for back stitching and zigzag stitching. Untwisting that occurs cannot be prevented.

[0010]

DISCLOSURE OF THE INVENTION The present invention provides a sewing thread which is improved in the above-mentioned drawbacks of the conventional sewing thread and is excellent in strength, untwisting resistance, high-speed sewability and fluff drop resistance. The task is to do so.

[0011]

According to the present invention, a thermoadhesive spun yarn containing 20 to 100% by weight of thermoadhesive short fibers having a melting point of 100 to 180 ° C. and a high melting point of 200 ° C. or more. Provided is a sewing machine thread having a filament thread as at least a constituent component, wherein the thermoadhesive short fiber and the high melting point filament have a joint point by fusion bonding. .

Further, according to the present invention, the melting point is 100 to 1
Containing 20 to 100% by weight of heat-bondable short fibers at 80 ° C.,
A thermoadhesive spun yarn having a ply twist in the Z direction and a melting point of 20.
Provided is a method for producing a sewing machine yarn, which comprises subjecting a high-melting-point filament yarn having a lower twist in the S direction at 0 ° C. or higher to a double twist in the Z direction to perform twisting.

In the present invention, the melting point is 100 to 180.
A thermoadhesive spun yarn containing 20 to 100% by weight of thermoadhesive short fibers at 0 ° C is used. The melting point of the heat-adhesive short fibers is 100.
When the temperature is less than ℃, the thermoadhesive short fibers are melted by the sewing machine needle heated by friction heat during sewing, causing sewing trouble, and further, the thermoadhesive short fibers are melted and flowed out at the time of dyeing. Then, the effect of the present invention is not achieved. On the other hand, when the melting point exceeds 180 ° C., high temperature is required for heat bonding, which is not preferable in terms of heat deterioration of fibers and processing cost.
A more preferable range of the melting point of the heat-adhesive short fibers is 13
It is 0 to 160 ° C.

The heat-adhesive short fibers can be formed of any polymer, but it is particularly preferable to form the copolyester.

The copolymerized polyester has, for example, terephthalic acid, isophthalic acid, paraoxybenzoic acid, cyclohexanedicarboxylic acid, adipic acid, sebacic acid, succinic acid and lower alkyl esters thereof as an acid component, and ethylene glycol, 1, 4-butanediol, 1,6-
Hexanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, neoventil glycol, etc. are used as the glycol component, and the melting point is within the range of 100 to 180 ° C. by combining various kinds of these monomers and their copolymerization ratios. Can be

As such a copolyester,
For example, terephthalic acid-isophthalic acid-1,4-butanediol copolymer, terephthalic acid-isophthalic acid-1,
Examples thereof include 6-hexanediol copolymer, terephthalic acid-isophthalic acid-ethylene glycol-diethylene glycol copolymer, terephthalic acid-adipic acid-ethylene glycol-1,4-butanediol copolymer and the like.

Among them, terephthalic acid, isophthalic acid,
Copolymerized polyester composed of 1,6-hexanediol is preferably used in terms of melt spinnability, stretchability and thermal adhesiveness.

The heat-adhesive short fibers used in the present invention are
It is not always necessary that they are all formed of the same component. From the viewpoint of strength and spinnability, a core-sheath type composite fiber having a high melting point polymer as a core component and a low melting point polymer having a melting point of 100 to 180 ° C. as a sheath component is preferably used.

In particular, the sheath component has a melting point of 100 to 180.
A core-sheath type composite fiber using the above-mentioned copolymerized polyester at 0 ° C. and a polyester having a melting point of 250 ° C. or higher in which 80% or more of the main repeating unit is ethylene terephthalate is suitable for the core component.

The core-sheath type composite fiber is a concentric type,
Any type such as an eccentric type or a type in which the core component is partially exposed on the surface can be used, and the weight ratio of the core component and the sheath component is within the range of 3: 7 to 7: 3. It is preferably about 1: 1 and particularly preferably about 1: 1.

The thermoadhesive spun yarn used in the present invention must contain 20 to 100% by weight of the above-mentioned thermoadhesive short fibers, and the content of the thermoadhesive short fibers is 20% by weight.
If it is less than the above, a sufficient adhesive effect cannot be obtained, and the object of the present invention cannot be achieved.

The thermoadhesive spun yarn may be composed entirely of thermoadhesive short fibers, but from the viewpoint of spinnability and strength, the content of the thermoadhesive short fibers is 30 to 60%. Particularly preferred.

The fibers mixed with the heat-adhesive short fibers are not particularly limited, but high melting point, high strength polyester short fibers are preferably exemplified. Although the denier and fiber length of these short fibers are not particularly limited, the denier is about 1 to 5 denier and the fiber length is 2 from the viewpoint of spinnability and thermal adhesiveness.
It is preferably about 0 to 50 mm.

The sewing thread of the present invention is constituted by compounding and integrating the thermoadhesive spun yarn containing the above-mentioned thermoadhesive short fibers and the high melting point filament yarn by twisting, blending or other methods. ing.

At this time, spun yarns or filament yarns other than the thermoadhesive spun yarn and the high melting point filament yarns may be combined within a range not impairing the object of the present invention.

The proportion of the heat-adhesive short fibers in the whole sewing thread is preferably 3 to 30% by weight. If the proportion of the heat-adhesive short fibers is too small, it becomes difficult to obtain a sufficient adhesive effect. On the contrary, if the proportion of the heat-adhesive short fibers is too large,
By heating in the sewing thread manufacturing process, the sewing threads are melt-bonded to each other, unwinding property is deteriorated, and further, during sewing, excess heat-adhesive short fibers are melted by a heated sewing needle,
This may increase the friction coefficient of the sewing thread and may cause the thread to break.

The high-melting point filament yarn constitutes the base of the sewing machine yarn, and is 20 in view of high-speed sewability.
It is necessary to have a melting point of 0 ° C. or higher. As a suitable example, a polyester filament yarn can be mentioned from the viewpoint of melting point and strength, and particularly preferable is a filament yarn made of polyester having an ethylene terephthalate unit as a main repeating unit.

In the sewing thread of the present invention, it is necessary that the heat-adhesive short fibers and the high-melting-point filament have a joint point by fusion bonding.

The term "joint point" as used herein means one of heat-bondable short fibers.
A portion in which one or a plurality of single yarns are bonded to one or a plurality of high melting point filaments by fusion bonding of the heat adhesive short fibers, a group of heat adhesive short fibers and a high melting point filament yarn Also includes a portion that is fused and bonded while maintaining each aggregated form.

By forming the above-mentioned joining points, the twist is fixed, untwisting that occurs during back stitching, zigzag stitching, etc. can be prevented, sewability is greatly improved, and fluff is less likely to fall off. .

For melt-bonding, it is convenient to use heat during the manufacturing process of the sewing thread, for example, twist setting step (in the case of polyester sewing thread, generally 90 to 1).
If the heat-adhesive short fibers are melt-bonded by using heat of a dyeing step (generally, for a polyester sewing thread, 80-140 ° C., 20-90 minutes) for about 30 minutes). The sewing thread of the present invention can be manufactured without increasing the cost.

The sewing thread of the present invention has improved heat resistance and wear resistance, and improved high-speed sewability, in which the thermoadhesive spun yarn is mainly in the inner layer portion and the high melting point filament yarn is in the outer layer portion. It is desirable to have a structure in which a part of the fluff of the thermally adhesive spun yarn is exposed on the surface layer portion of the sewing thread. The amount of fluff is preferably 100 fibers / m or more.

Such a structure can be obtained by using a method generally called covering, in which the thermoadhesive spun yarn is covered with the high melting point filament yarn, but in view of processability and cost, Twist in the Z direction is imparted to the thermoadhesive spun yarn, and twisting in the S direction is applied to the high melting point filament yarn, and then the thermoadhesive spun yarn and the high melting point filament yarn are twisted in the Z direction. It can be easily obtained by twisting and twisting.

That is, at the time of plying in the Z direction by twisting, the Z-twisted thermoadhesive spun yarn is twisted and twisted, and S
The twisted high melting point filament yarn is untwisted and stretched. Therefore, the thermoadhesive spun yarn is arranged in the inner layer portion of the sewing thread, and the high melting point filament yarn is arranged in the outer layer portion of the sewing thread.

Furthermore, when the high melting point filament yarn is untwisted, the filaments are opened and many voids are formed, so that the fluff of the thermoadhesive spun yarn is likely to be exposed on the surface layer portion of the sewing machine thread. The sewing machine thread structure can be easily obtained.

The sewing thread of the present invention thus obtained preferably has a strength of 4.5 g / de or more, an elongation of 5 to 30%, and a Young's modulus of 300 to 1000 kg / mm ² .

The melting point of each fiber in the present invention is D
It was measured from an endothermic and exothermic curve of SC.

[0038]

In the thermoadhesive spun yarn used for the sewing machine yarn of the present invention, since the contained thermoadhesive short fibers are fluffy, the contact area with the high-melting filament yarn is widened and the melt adhesion is improved. The action becomes large.

Further, since the fluffy heat-adhesive short fibers are inserted between the high-melting filament yarns and melt-bonded to each other, the twist-fixing effect is significantly larger than that of the conventional sewing thread using the heat-adhesive filaments. Improve to. By this action,
The sewing thread of the present invention has excellent resistance to untwisting, and the sewability of a sewing type sewing machine in which the untwisting sewing thread such as back stitching and zigzag sewing is dramatically improved.

Further, since the sewing thread of the present invention contains the spun thread, the fluff thereof exhibits a heat radiating action, and further exhibits a cushioning action against abrasion, thereby improving the high-speed sewability. In particular, this effect becomes remarkable when the fluff is exposed on the surface layer of the sewing thread.

Further, in the sewing thread of the present invention, since the root of the fluff is firmly adhered and fixed as described above, the fluff is very unlikely to fall off.

The sewing thread of the present invention is not limited to spun yarn,
Since it also includes filament yarn with high strength,
It is possible to realize sufficient strength as a sewing thread.

[0043]

EXAMPLES The present invention will be described in more detail below with reference to examples. The strength of the sewing thread, the zigzag sewability, the high-speed sewability, and the fluff shedding resistance were measured as follows.

(1) Strength It was measured according to JIS-L-1013-7.5.1.

(2) Zigzag stitch sewing machine A zigzag stitch sewing machine is used, the speed is 2500 rpm, and the sewing machine needle #
14. Three T / R surges were sewn with a sewing needle swing width of 5 mm / stitch and a stitch pitch of 5 mm / stitch, and the sewing length is shown until the sewing thread is cut. The longer this length is, the better the zigzag stitchability is.

(3) High-speed sewability 10 pieces of T / R surges are sewn at a speed of 3000 rpm, a sewing machine needle # 14, a stitch pitch of 5 mm / stitch using a single-needle, lockstitch sewing machine to cut the sewing thread. The length that was sewn up to was shown. The longer the length, the better the high-speed sewability.

(4) Falling off of fluff Using a cleaned single-needle sewing machine, speed 3000 rpm
m, sewing needle # 14, stitch pitch 5 mm / stitch,
The amount of fluff attached to the sewing machine hook portion and the presser portion after sewing 5 sheets of T / R surge for 10 m is shown.

[Examples 1 to 4 and Comparative Example 1] An acid component having a terephthalic acid / isophthalic acid molar ratio of 90/10,
Using a copolyester having an intrinsic viscosity of 0.66 obtained from a glycol component of 6-hexanediol as a sheath component and polyethylene terephthalate having an intrinsic viscosity of 0.63 as a core component, by a usual conjugate spinning method, The weight ratio was set to 1: 1 to obtain a heat-bondable short fiber composed of a core-sheath type composite fiber having a single fiber fineness of 3 denier and a fiber length of 44 mm. The melting point of the copolyester of the sheath was 135 ° C.

The heat-adhesive short fibers and the single fiber fineness of 1.2
Denier and polyethylene terephthalate short fibers having a fiber length of 44 mm were mixed-spun so that the content (weight mixing ratio) of the heat-adhesive short fibers would be the value shown in Table 1, and Z-twist heat-adhesive spinning of No. 30 count respectively. I got a thread.

Next, three 250-denier, 48-filament polyethylene terephthalate filament yarns (melting point 260 ° C.) twisted in the S direction of 500 T / M, which were obtained by a conventional method, and three single yarns and each of the above-mentioned thermal adhesiveness were obtained. Spun yarn 1
After aligning with a book and twisting by twisting in the Z direction at 400 T / M, the dyeing process was performed at 130 ° C. for 30 minutes.

At this time, a part of the heat-adhesive short fibers was melted and adhered to the polyethylene terephthalate filament yarn. Thereafter, 3% by weight of a silicone-based oil for sewing machine threads was applied to obtain a sewing machine thread.

In each of the obtained sewing threads, the thermoadhesive spun yarn is located in the inner layer portion of the sewing thread, and the high melting point polyethylene terephthalate filament yarn is located in the outer layer portion of the sewing thread. Part of the fluff of spun yarn (200
~ 900 yarns / m) were exposed at the surface layer of the sewing machine thread.

The results are shown in Table 1, and when the content of the heat-adhesive short fibers in the heat-adhesive spun yarn is 20% by weight or more (Examples 1 to 4), the strength and the zigzag stitch are sewn. Of sewing machine thread having excellent resistance (untwisting resistance in zigzag stitching), high-speed sewability and fluff shedding resistance, especially when the content of the heat-adhesive short fibers is 30 to 60% by weight (implementation) Example 2,
The result of 3) is excellent.

On the other hand, when the content of the heat-adhesive short fibers is less than 20% by weight (Comparative Example 1), the zigzag stitchability is inferior and the fluff is frequently dropped.

[Comparative Example 2] In Example 2, instead of the polyethylene terephthalate filament yarn, the S twist spun yarn of No. 30 made of polyethylene terephthalate short fibers having a single fiber fineness of 1.2 denier and a fiber length of 44 mm was used. The same conditions as in Example 2 were used to obtain a sewing thread consisting only of polyester spun yarn.

The results are as shown in Table 1. The sewing machine has low strength, the zigzag sewability is slightly inferior, and the fluff comes off relatively frequently.

Comparative Example 3 In Example 2, the core-sheath type composite fiber used as the heat-bondable short fiber of the heat-bondable spun yarn was formed into a heat-bondable filament yarn without cutting, and the heat-bonded filament yarn was prepared. In place of the thermo-adhesive spun yarn, the polyethylene filament terephthalate filament yarn of Example 2
A 5% by weight mixed fiber was used, and the other conditions were the same as in Example 2 to obtain a sewing thread consisting only of polyester filaments.

The results are shown in Table 1, and the sewing thread is inferior in high-speed sewability and zigzag sewability.

[0059]

[Table 1]

[0060]

According to the present invention, there is provided a sewing thread which has high strength, can prevent untwisting that occurs during back stitching, zigzag stitching, etc., has excellent high-speed sewability, and has less fluffing. can do.

Claims (4)

[Claims] 1. A sewing machine comprising, as components, at least a thermoadhesive spun yarn containing 20 to 100% by weight of a thermoadhesive short fiber having a melting point of 100 to 180 ° C. and a high melting point filament yarn having a melting point of 200 ° C. or more. A sewing thread, wherein the thermo-adhesive short fibers and the high-melting-point filaments have a joining point by fusion bonding. 2. The thermoadhesive spun yarn mainly forms an inner layer portion of the sewing thread, the high melting point filament yarn forms an outer layer portion of the sewing thread, and part of the fluff of the thermoadhesive spun yarn is the sewing machine. The sewing thread according to claim 1, which is exposed at the surface layer of the thread. 3. The heat-adhesive short fibers have a sheath component of a copolyester having a melting point of 100 to 180 ° C.
The sewing thread according to claim 1 or 2, which is a core-sheath type composite fiber having a core component of polyester having a melting point of ℃ or more. 4. A thermoadhesive spun yarn containing 20 to 100% by weight of a thermoadhesive short fiber having a melting point of 100 to 180 ° C. and having a Z direction twist, and a melting point of 200 ° C. or more and an S direction. A method for producing a sewing machine thread, which comprises subjecting a high-melting-point filament yarn having undertwisting to upper twisting in the Z direction to perform twisting.