JPS61108746A - Core yarn sewing yarn - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a core yarn sewing thread having a filament yarn of Naitan 46 fiber as a core yarn, which has excellent heat resistance and is suitable for high-speed sewing or sewing thick fabrics.

(Prior Art) Conventionally, various sewing threads have been developed for different uses such as clothing and industrial use. Among these, the development and development of synthetic fiber sewing threads has been remarkable.And among synthetic fiber materials, polyester fibers and polyamide fibers are two sides of the same coin - their high strength and abrasion resistance. , due to cost advantages and other factors, 1.
It has grown into a major sewing thread material for clothing and industrial use. In addition, these synthetic fibers have a weakness in heat resistance compared to natural fibers such as cotton 1/linen, so they are made with cotton as a so-called core yarn, which has cotton, which has excellent heat resistance, as the sheath component and polyester filament as the core yarn. Core yarn sewing threads that have both heat resistance and the high tenacity of polyester have also been developed.

(Problems to be Solved by the Invention) As mentioned above, the sewing thread made of polyester fiber and polyamide fiber, which is the main material of the sewing thread, has excellent characteristics such as high strength and abrasion resistance when suitable sewing conditions are selected. The melting point of these fibers is at most 230~2.
The temperature is 60° C., and under severe sewing conditions such as high-speed sewing or when sewing thick fabrics together, there is a drawback that the sewing needle melts and breaks due to the frictional heat generated when the sewing needle penetrates the fabric during one sewing. Also,
Although continuous multifilament yarn made of these fibers is used as the core yarn and natural fiber staples such as cotton are used as the sheath component, the heat resistance of takoyarn sewing threads has been improved to some extent; It is difficult to cover the filament thread of the core thread, and the 71° lament part that appears on the surface comes into contact with the sewing needle, which becomes hot due to frictional heat during sewing, and melts, resulting in a significant decrease in strength. . In addition, there are sewing threads that use heat-resistant fibers such as aromatic polyamide to provide heat resistance, but these fibers are highly rigid and expensive, and are not suitable for general clothing.
It has been desired for a long time to develop a sewing thread that overcomes these drawbacks (unsuitable for industrial use).

(Means for Solving the Problems) In order to solve the problems, the present invention takes the following measures. That is, 1. the present invention is a core yarn sewing thread composed of a core yarn formed by using a filament yarn as a core yarn and wrapping this with a 31 m staple fiber,
The filament thread is a core yarn sewing thread characterized by being made of nylon 46 fiber.

The present invention will be explained in detail below.

The core yarn constituting the core yarn sewing thread of the present invention uses a filament yarn of nylon 46 fiber as a core yarn, and the reason for this is to impart heat resistance to the sewing thread. 90 weight'j1% or more (-xm-(OH,)4- mua
o - (OHI) 4-00+ polyamide fibers (hexamethylene terephthalamide) consisting essentially of poly(tetramethylene azimide), poly(undecamethylene terephthalamide), etc. May contain a blend of the following: 0 Also, if necessary, a matting agent, pigment, light stabilizer 1 heat stabilizer, antioxidant, antistatic agent 1 dyeability improver or adhesion improver, etc. All of them can be used, except those that seriously affect the characteristics of the present invention depending on their formulation.

Then, the nylon 46 fiber was dissolved in a 96.3% concentrated sulfuric acid solution so that the polymer concentration was 10q/-, and the ! ! The relative viscosity measured at 0°C is preferably 2.4.
The melting point of nylon 6 or nylon 66 is higher than 1 and even higher strength.
This is extremely high compared to ~260°C, and the present invention aims to utilize this high melting point to improve the heat resistance of sewing thread to frictional heat. Incidentally, the filament yarn may be either a monofilament yarn or a multifilament yarn, but the latter is preferable since it provides flexibility.

On the other hand, the staple fiber that serves as a sheath component for covering the nylon 46 fiber filament yarn of the core yarn and further improving the heat resistance of the core yarn preferably has a melting point of 250°C or higher,
More preferably, it is necessary to use a material with a temperature of 255° C. or higher.

The reason for this is that filament staple fibers, which have a strong and dominant influence on sewing thread, do not require severe heat resistance, but when the melting point reaches 250'O, it is difficult to perform harsh sewing such as high speed sewing or thick material sewing. When sewn under such conditions, it will melt when it comes into contact with a sewing needle that has risen to a high temperature, causing strength deterioration or discoloration, impairing the appearance of the seams, and also significantly reducing the heat resistance imparting effect of the core thread. So at least melting point 250'
It is preferable to use 0 or more staple fibers.

The melting point (1)) mentioned here is measured using a differential scanning calorimeter (Sh
imagu Differ@ntial Scanni
The type of staple fiber preferably has a melting point of 250°C or higher. The staple fibers may be of any material, or may be a mixture of one or more of them, as long as they provide the performance as a sewing thread. Note that the melting point is the temperature at the peak of the melting endothermic curve measured by the differential scanning calorimeter ("
O). However, it is preferable to use polyamide fibers of the same type as filaments because they can impart high strength and wear resistance, and can be dyed in the same bath. Equal length cut fibers used from short fiber spinning to long fiber spinning
! It also includes unequal length fibers or cut fibers obtained by tow spinning. In addition, the composition ratio of multifilament and staple fibers is such that the total weight ratio of staple fibers is 25 to 60.
It is preferable that the ratio is in the range of %. If the composition ratio is less than 25%, it will be difficult to sufficiently treat the core filament yarn, resulting in insufficient heat resistance, and if it exceeds 60%, coverage will improve, but the high strength of the core nylon 46 fiber filament will be reduced. 1. Since the impact resistance and the effect of reflecting the uniformity of the filament yarn physical properties in the sewing thread are reduced, it is preferable to configure it within the above range.

Preferably, 2 to 6 core yarns are twisted together to form a core yarn sewing thread. If there is only one thread, there is a problem of thread breakage due to thread breakage, especially when used as a needle thread, and if there are more than six threads, there is a problem in terms of thickness. In addition, the direction of twisting is preferably two directions, and the number of twists is from furnace OQ to /σO
υ1/+++ is preferred.

As a method for manufacturing the core yarn sewing thread of the present invention, conventionally known core yarn manufacturing equipment can be used. For example, a multifilament yarn made of nylon 46 fiber as a core yarn is drafted in front of a spinning frame machine. It is supplied together with 7 leases and twisted once to produce core yarn. The obtained core yarn is twisted in plurality, preferably in the two-twist direction, which is opposite to the single-filament twist direction, and subjected to one dyeing process, and then a smoothing agent is applied thereto to obtain the desired core yarn sewing thread. In addition, the core yarn sewing thread of the present invention can be heat-treated after the core yarn is single yarn or plied and twisted to improve the initial Young's modulus, reduce stitch skipping and thread breakage, and further improve sewing properties. 1. .

(Example) A 150 denier/48 filament nylon 46 fiber multifilament yarn was combined with 7 leases of a 1 or 2 denier 44 cut length nylon 46 fiber stable that was drafted in front of the 70 controller of a spinning machine. The core yarn was twisted with a twist coefficient of 4.0 (calculated as the number of twists per inch of cotton count) to obtain a core yarn of Nego'B (weight % of staple fibers was 43.6 weight %). Then, add 3 layers of this core yarn.
This is twisted in the opposite direction to the single yarn twist.
After twisting with the number of twists, a non-contact type heater was used to set a fixed length at 230° C. for A5 sec. After that, roll it up into 1 soft roll cheese, use acid dye, and boil it for 40 minutes.
Stained in minutes. A sewing thread (A1) sample was prepared by attaching 3% of a silicone-based oil to the obtained dyed thread, and the sewing thread physical properties and sewability tests were conducted.The results are shown in Table 1.

In addition, in order to compare with the above sample, a 150 denier 48 filament polyester filament yarn was twisted under the same conditions in which cotton was wrapped around the core yarn, and a cotton/polyester core yarn sewing thread 2° (Ne 20/3) coated with the same oil was used. (
A2) was prepared, and sewing thread physical properties and sewability tests were conducted and compared.

In addition, commercially available polyester spun sewing thread $20 (A3), t" polyester filament sewing thread #20 (A4), and Naitan 46 filament sewing thread are widely used in the industry and have relatively excellent heat resistance. I have listed the comparisons of ginseng go (As).

In the table above, the strength and elongation (breaking) are the values measured using a constant speed extension type tensile tester (Tensilon manufactured by Toyo Baldwin), and the melting point is measured using a differential scanning calorimeter (DSO). . Note that the melting point of the cotton/polyester yarn sewing thread indicated the melting point of the polyester filament.

Thread breakage in the sewability test was evaluated by the number of thread breakages when 50 layers of denim fabric were sewn using a lockstitch sewing machine at 2800 rpm. In addition, the number of lines was evaluated based on the maximum number of layers that could be sewn without thread breakage at a sewing length of 2 m using denim fabric, and this evaluation indicates the degree to which it can withstand severe sewing. Even when sewing such dense, thick fabrics, thread breakage is rare, the number of threads is significantly superior to that of conventional sewing thread, and it can withstand even severe sewing operations.

(Effect of the invention)

Claims (1)

[Claims] 1. A core yarn sewing thread comprising a core yarn made of a filament yarn wrapped with staple fibers, the filament yarn being comprised of nylon 46 fibers.