JPS62257434A - 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 sewing thread. More specifically, the present invention relates to a composite yarn at least partially composed of thermoplastic synthetic fiber multifilament 1-based yarn, which has improved sewing thread properties.

(Prior Art) Sewing threads made of multifilament yarns are stronger, more abrasion resistant, and more uniform than sewing threads made of short fibers, so they have been widely used in the past.

However, because the bulkiness is poor and the bending rigidity is large, the sewing thread does not fit well with the fabric surface after the seam is formed, and the sewing thread rises in an arch shape from the fabric surface, and the sewing thread becomes sharp during zigzag stitching. The defect is that it does not show proper bending and the seams are messy.

If the tension of the sewing thread is increased during sewing in order to make the stitches neat, fine wrinkles will occur in the 1 part of the sewing machine, which will deteriorate the quality of the sewn product.

In addition, the surface of the yarn is smooth and there are no fluffs that protrude on the surface like spun yarn, making it easy to wear! ! Because the resistance is low, the twists move easily and the snarl absorption is poor. Therefore, the range of the number of twists in which snarls do not occur is narrow, and there are many cases where snarls occur due to slight twisting of the sewing thread that occurs during sewing, and sewing threads that become tangled or unstitched. It reduces efficiency.

On the other hand, stretchable bulky threads obtained by crimping multifilament threads of thermoplastic synthetic fibers are also used as sewing threads, but when the sewing machine needle moves from the top dead center to the bottom dead center, Because of its elasticity, it does not converge to form a loop and is secretly attached to the sewing machine τ1, so the tip of the hook or the lower thread looper cannot satisfactorily catch the upper thread and cannot be used as the upper thread.

(Problems to be Solved by the Invention) The purpose of the present invention is to improve the defects of the prior art as described above, and to provide a yarn that is composed of multifilament yarns, has less snarl, is bulky, and has a structure that does not interfere with the fabric. It is an object of the present invention to provide a suture thread that has good conformability and is capable of forming stable loops.

(Means for Solving the Problems) In order to achieve the above object, the present invention has the following configuration.

That is, it is a composite yarn consisting of a multifilament yarn, at least a part of which is a thermoplastic synthetic fiber multifilament yarn, and the composite yarn has a bulkiness of 2. ．． 5o+t
/(J or more, and the elongation of the composite yarn during cart IQ/D is 7% or less.

The sewing thread according to the present invention is composed of multifilament threads made of the same or different materials, and at least a part of the threads is a composite thread made of multifilament thermoplastic synthetic resin fibers. This composite yarn consists of two elements: an element that maintains strength and elongation characteristics such as strength, elongation, and bending stiffness, and an element that maintains bulk. The former element that maintains strength and elongation is made up of a relatively thick monofilament IF and forms the core yarn located at the center of the composite yarn, while the latter element that maintains bulkiness is relatively thick. It consists of a group of thin monofilaments or a group of crimped monofilaments, which are located on the outside of the composite yarn and form a loop to form a sheath yarn, which are connected to each other in a continuous entanglement. It forms a composite yarn with a core-sheath structure.

The multifilament yarn constituting the core yarn is made of thermoplastic synthetic fiber. The reason for this is that thermoplastic synthetic fibers have the property that properties such as yarn shrinkage rate and strength/elongation can be adjusted to arbitrary values by heat treatment or the like.

On the other hand, the material of the multifilament yarn forming the sheath thread is not particularly limited, but may include natural fibers such as silk, cellulose fibers such as rayon, semi-synthetic fibers such as acetate, polyamide, polyester, polyacrylic, and polyolefin. Synthetic fibers such as synthetic fibers must be able to be continuously entangled.

Of course, the sewing thread according to the present invention can be used as a single composite yarn with the above-mentioned core-sheath structure, but it can also be used as a twisted yarn made by giving a first twist to these yarns and then aligning a plurality of threads and heating them. Furthermore, it is also possible to use a plurality of twisted yarns as plied yarns which are further aligned and heated.

The sewing thread according to the present invention has a bulk height of 2.5a (/Q or more).If the bulk height is less than 2.5cnf/CI, the bending stiffness of the sewing thread becomes too large, and after the seam is formed, it becomes difficult to connect to the fabric. It does not blend well, reduces snarl absorbency, and reduces stitchability.

Further, the sewing thread according to the present invention has an elongation of 7% or less when the cart is 1 Ω/D. The reason for this structure is that when stitches are formed intermittently one stitch at a time, as in sewing with a sewing machine, the sewing thread used as the upper thread is repeatedly stretched and loosened as the sewing machine needle moves up and down. The extension 41 given by the descent from the top dead center to the bottom dead center must be recovered while the sewing machine needle moves from the bottom dead center to the top dead center. Therefore, the time required to complete elongation of the upper thread depends on the sewing speed of the sewing machine, and the faster the sewing speed is, the shorter the distance between the rollers becomes. Therefore, for high-speed sewing, the number of revolutions/l of the sewing machine, OOOP
In order to withstand more than RM, it must have a corresponding elastic recovery force. Like this 4 [Characteristics are sewing thread load 1g
Achieve J: by keeping the elongation at /D within 7%.

FIG. 1 is a sectional view showing an example of a sewing thread according to the present invention,
FIG. 2 is a sectional view of another example of the yarn according to the present invention.

Fig. 1 shows a sewing thread consisting of a one-water composite thread 17, in which a multifilament 18 of thermoplastic synthetic fiber constituting the core thread is located at the center, and a multifilament 19 forming a half-sheath thread (1! are distributed throughout the cross-section of the suture, and these individual filaments form loop-shaped fuzz 21.
The core yarn is made to protrude to the outside 20 of the composite yarn, and is also bent into a loop shape at the center part, and the core yarn is inserted between the 4F multifilaments 18 and intertwined with each other to form an integral structure by continuous entanglement. combined.

This sewing thread is twisted in order to maintain bulkiness at an appropriate temperature and to maintain the form of a composite thread.

If snarls occur due to the addition of the first twist, an appropriate twisting treatment such as heating is performed.

The one shown in Figure 2 was obtained by adding a first twist to the composite yarn shown in Figure 1, and then arranging three composite yarns with this first twist and giving them a final twist in the direction opposite to the first twist. This is a triple twist sewing thread 22. In the sewing thread 22 of this form, the filament highs constituting 4M of the core thread of the composite thread 17 gather at the center, and the inner part of the filaments forming the sheath thread is tightened at the nip part 23. Therefore, the shape is also stable. Also, the outer part 2/I of the sewing thread 22
4F is a bulky, soft-textured suture with many loops of the sheath thread exposed like fluff. The amount of ply twist and ply twist given to this thread is determined by the bulkiness of the thread, shape retention ↑ (eye 3 wrinkle absorption -
It is determined in consideration of t'1, etc., and further treatments such as heat treatment are performed as appropriate.

Furthermore, it is also possible to make a plied yarn by aligning a plurality of yarns shown in FIG.

Load 1 of the sewing thread according to the present invention The elongation at Q/D is normal S
It can be determined from the -8 curve, or by reading a cart at an elongation of 7% using a Schopper type tensile tester. The fineness at this time is determined by the oil agent (=
The fineness is calculated by correcting the J-wearing amount.

In addition, the bulk height is determined as follows.

FIG. 3 is a schematic diagram schematically showing the main parts of the bulk height measuring device.

The flat plate 28 is held horizontally, and in the center of the flat plate 2B, slits 27, 27- are provided parallel to each other over a length of 3 cm so that the outer edges form three strokes. - is designed so that the circumferential length measurement chip 726 can freely pass through. The circumferential length measurement chip 126 has a width of 2.
5cm long, made into a loop with 27 slits on each end.
．． It is further coupled through 27-. A load 29 of 50 q is placed at both ends of the tape, and a pointer 30 is attached to the load 29 so as to be horizontal.

On the other hand, a scale plate 31 is held vertically on the lower side of the flat plate, close to the slit and facing the surface pointer.

This scale plate 31 has a scale engraved upward, with O indicating the position where the pointer stops when the front vehicle is suspended without a sample. ′+A′fr1 of the tape can be freely bent and curved (it only needs to be thin and easily stretchable when handling a load, preferably a thin fabric made of synthetic fibers or a thin polynisdel stretched film). .

A plurality of small pieces of a certain length are made so that the total fineness of the sewing thread to be measured is 500,000 to 800,000 deniers. The fineness of the sewing thread is determined from the weight of the obtained small piece. If the thread contains water-absorbing fibers, determine not the apparent fiber density but the positive fineness, and if the sewing thread has been treated with an oil agent, determine the oil agent @ star in advance.

Place the bundle 25 on the flat plate 28 of the bulkiness measuring device with the arms parallel to the appropriate side, pass it through the loop of the circumference measuring tee 126, and then gently hang the cart 29. When the cart is stable, the pointer 30 Read the value of 0 from the scale plate 31 for the position of
Next, the bulk height "-7g" is determined from equation (1).

(2D, +0.3>2 F(cnflo)=-□・900.0004πnD D, movement length of the second finger 11 cm) n: Number of sewing threads gripped by the circumference measurement tape (Thursday) D : Correct hanging fiber of sewing thread) Good (denier) However, if the amount of lubricant exceeds 0.5%, correct the normal fineness using the following formula (2).

D=D-(1-->(2>here)
D': Degree of correctness (denier) in the state of oil-filled container α: Amount of oil applied (%) The bulkiness of the sewing thread according to the present invention is determined by the length of the multifilament thread of the core thread and the multi-filament thread of the sheath thread. Although it varies depending on the yarn length difference of the filament yarn, the shrinkage rate, the number of twists of the composite yarn, etc., the factor that has the greatest influence is the above-mentioned yarn length difference.

This yarn length difference depends on the manufacturing conditions of the composite yarn and the shrinkage rate of each multifilament yarn. The yarn length difference is determined by equation (3).

K (%) = F2-((Sz-3t) 1 F1) (3)
Fl: Feed rate of core yarn (%) 2: Feed rate of sheath yarn (%) Sl: Shrinkage rate of core yarn (%) S2 Shrinkage rate of double sheath yarn (%) The shrinkage rate referred to here is It is the sum of shrinkage rates caused by heat treatment, dyeing, etc.

According to the present invention, each filament of the core yarn and the sheath yarn is intertwined with each other to form a composite yarn. When manufacturing a composite yarn, it is desirable that the original twist is /10T/M or less to ensure good movement of individual filaments.

In addition, the single fibers of the multifilament yarn that will become the core yarn are preferably thick and have a thickness of 1.5 to 7 d, and the single fibers of the multifilament yarn that will become the sheath yarn are preferably about 1.0 to 3 d. .

The core yarn should be selected to be suitable for maintaining the strength and elongation properties of the composite yarn, and should also have a relatively low shrinkage rate. In addition, in order to freely adjust the elongation properties and shrinkage rate, it is necessary to use thermoplastic fibers. On the other hand, the sheath yarn has bulkiness and increases the friction on the surface of the composite yarn, as well as maintains the appearance, and is not limited to 14, but in the case of dyeing, one with good color development is selected.

FIG. 4 is a schematic diagram showing an apparatus for manufacturing composite yarn used in the present invention.

In FIG. 4, the core yarn 1 is a thermoplastic synthetic fiber multifilament yarn, which is unwound from a bobbin 3 and is unwound from a yarn guiding guide 5.
Tension device7. The yarn is supplied to the air entangling nozzle 15 via the yarn feeding roller 9. On the other hand, the sheath yarn 2 is unwound from the bobbin 4, and is supplied to the air entangling nozzle 15 through the yarn guide 6, tension device 8, and yarn feeder 10, where it is entangled together with the core yarn. It is wound up into a package 16 via a take-up roller 11.

The air entangling nozzle 15 generates a turbulent air flow using compressed air, and the filaments of the core yarn 1 and the sheath yarn 4 are continuously entangled with each other by this turbulent air flow to form an integrated composite yarn.

The core yarn needs to be sufficiently opened by the turbulence of the air entangling nozzle 15. The spreadability of the core yarn 1 depends on the feed rate of the core yarn, but the overfeed rate should be at least 5%. The overfeed rate is adjusted by the surface speed of the take-off roller 11 and the yarn feeding roller 9.

Similarly, the overfeed rate of the sheath yarn is adjusted by the surface speed of the take-off roller 11 and the yarn feeding roller 10.

(As shown in equation 3, the yarn length difference has an important effect on the properties of the composite yarn, so this decision must be made carefully. If the value of K is 2.8% or less, the bulkiness is satisfactory. If the sheath yarn does not have crimp when it approaches 20%,
It becomes difficult to form a composite yarn. When a bulky composite yarn with a large K value is required, a crimped yarn may be used as the sheath yarn 2.

FIG. 5 is a schematic diagram of an apparatus for crimping the sheath yarn to make a composite yarn.

In FIG. 5, when manufacturing a composite yarn, the sheath yarn 2 is fed to an air entangling nozzle 15 while being crimped. As is clear from FIG. 5, a heating device 13, a false twisting device 14, and an intermediate yarn feeding roller 12 are inserted between the yarn feeding roller 10 and the air entangling nozzle 15 in the embodiment shown in FIG. In this case, the A-buffed ratio of the sheath yarn depends on the surface speed of the intermediate yarn feeding roller 12. Although a false twisting device is shown in FIG. 5, it is also possible to use other crimping devices, such as a forming crimping device using a gear or the like or a push-in crimping neck.

What should be noted here is that when dyeing or heat treating the composite yarn produced by the apparatus shown in Figures 4 and 5 alone or after making it into twisted yarn or plied yarn, the shrinkage rate S
1. The value of K should be determined in consideration of the value of S2. If this is not done, the desired sewing thread properties may not be obtained. The shrinkage value 81 of the core thread must be 7% or less in order to stabilize the properties of the composite thread or sewing thread, and is preferably as small as possible. On the other hand, the shrinkage rate 82 of the sheath yarn must also be determined in consideration of the relationship with the value of the feed angle of the sheath yarn -1=2. The desired bulkiness cannot be obtained unless the value of K is at least 2.8%.

(Examples) Example 1 A composite thread was manufactured using the apparatus shown in FIG. 4, and the physical properties of the obtained sewing thread are shown in Table 1.

In Table 1, the triple-twisted yarn is placed in a package of 1ki5 on a metal drum with a tension of 38Q) at 170'C.
Heat treatment was performed using a hot air dryer for 100 minutes. Further, this thread was dyed with a soft winder for 55 minutes, with a winding density of 0.43CI/-, and a high pressure cheese dyeing machine was used to dye the yarn with disperse dye for 130'C/l○ minutes to produce 1 green sewing thread.
'', f.Oil agent shop 11i (=1-ton winding of 200 Qrn and 100 m card winding.

As comparative examples, commercially available spun polyester sewing threads, polyester filament sewing threads, and triplet twisted threads of Example 1 were directly dyed without being subjected to a heat treatment of 170'CX100 minutes. In all of these comparative examples, the characteristic values marked with * are insufficient.

The yarn obtained in Example 1 was sewn into a 5 oz.
7 sails 15 with a square V-dore weight, 2 rotations.
Continuous 1 m sewing was repeated 5 times at 43 ORPM.

Other conditions for sewing are as follows: Sewing machine $1 = Organ DP-5 #19 Needle thread tension crab
520±50C) Width: 10 mm Stitch Vl: 126 stitches/3 cm The sewing thread according to the present invention does not cut at all, and is well-stitched and adheres well to the fabric. Even when the angle changed from side to side, the seams were bent sharply and a sewn product with excellent appearance quality was obtained.

On the other hand, when the spun polyester sewing thread passes through the fabric, it is greatly elongated, resulting in poor loop stability and thread breakage on two sides, as well as two skipped stitches, making it impossible to sew normally. .

In addition, polyester filament sewing thread has a change in the number of twists due to repeated heating and untwisting of the sewing thread each time the sewing direction changes from side to side, and combined with the tightening by the thread guide, the twist balance of the ply twist is disrupted, resulting in snarl. This caused thread breakage, making it impossible to sew a continuous length of 1 m.

In addition, 170'CX100 minutes of dry heat 1 The sewing thread has no snarls due to changes in the number of twists.Fabric Ω
As with spun sewing thread, it was not possible to sew satisfactorily due to the large resistance and large elongation at the appropriate time.

Example 2 Composite yarn was obtained using the one-purchase shown in FIG.
In the same manner as above, polyester multifilamen 1~ thread was used as a core thread and a sheath thread to prepare a sewing thread. However, 170″CX10
A 0-minute standstill treatment was not performed.

In addition, this was also carried out for sheath yarns of 6.7%, 18.0%, and 20.8%, but the K value of 6.7% was O, and a satisfactory continuous entangled yarn could not be obtained. If the thread was more than .0, the sheath thread had poor defibration properties and the composite thread lacked uniformity, so processing as a sewing thread was discontinued.

The manufacturing conditions a3 and the characteristics of the sewing thread are shown in Table 2.

As can be seen from Table 2, the bulkiness depends on the difference in the core-sheath feed rate, but the elongation at a load of 1Ω/D remains constant.

As a comparative example, 270D/3 polyester filament sewing thread made by Ichinomi is shown.

As a result of the same sewing test as in Example 1, satisfactory results were obtained for Levels 2 and 3. Water 1 [1 is satisfactory in sewing, but there are some difficulties in blending with the fabric].

Example 3 A composite yarn was made using the apparatus shown in FIG. 5, and the obtained composite yarn was processed according to Example 2 to obtain a sewing thread of 17. Table 3 shows the properties of manufactured strips 1 and 1h.

The false twisting conditions for imparting crimps to the sheath yarn were similar to the conditions for commonly performed stretch crimped yarns, and the resulting stretch crimped yarn had a stretch elongation rate of 33%.

In this case, the overfeed rate of the sheath yarn is determined by the surface speed of the take-off roller 11 and the intermediate yarn feeding roller 12.

Comparing Tables 2 and 3, in Table 3, the overfeed rate of the sheath yarn is 3 because stretch crimped yarn is used as the sheath yarn.
Even if it is increased to 0%, 1q of normal composite yarn is still removed. Even at the same overfeed rate, the crimped yarn has a higher bulkiness, and the bulkiness increases as the overfeeding increases. However, the elongation at a load of 1 g/D maintains a constant value because the physical properties of the core yarn and the overfeed rate remain unchanged.

The material shown in Water Q't% 4 in Table 3 shows the same bulkiness as the commercially available single cotton sewing thread shown in the comparative example, and the elongation at a load of 1 g/D is 4.5%. It can be seen that the elasticity is low, difficult to stretch, and has good elastic recovery.

Sewing tests were conducted according to Example 1, but all results were satisfactory.

(Effects of the Invention) Since the present invention has the above-described configuration, the following effects 8 can be obtained.
Qin.

(1) Even though it is a sewing thread made of multifilament thread, it is bulky and soft, so it blends well with the fabric.
Moreover, when changing the sewing direction, the sewing thread bends sharply to form a good seam.

(2) A core yarn in which the sewing thread has resistance to elongation and the elongated thread has a recovery function, that is, maintains strong elongation characteristics;
Mainly because it is composed of a composite yarn in which sheath yarns that maintain bulk and surface friction resistance are joined together by continuous entanglement,
There is resistance to external elongation, and there is no decrease in bulk due to elongation.

(3) The composite yarn used in the present invention has loops protruding like fluff on the surface of the yarn and has high frictional resistance, so there is little twist movement during ironing and rubbing, and high snarl absorbency.

(4) Bulk height and load 1 (7/D) Elongation can also be adjusted to the desired vessel by appropriately selecting manufacturing conditions and the type of element H used.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an example of a sewing thread according to the present invention. FIG. 2 is a schematic diagram schematically showing the main parts of the high altitude measuring device. FIG. 3 is a schematic diagram schematically showing the main parts of the bulk height measuring device. FIGS. 4 and 5 are schematic diagrams showing a composite yarn manufacturing apparatus according to the present invention. 1: Core thread 2: Sheath thread 15: Air entangling nozzle 17: Composite thread 22: Sewing thread

Claims (3)

[Claims] (1) A composite yarn consisting of a multifilament yarn, at least a part of which is a thermoplastic synthetic fiber multifilament yarn, the composite yarn having a bulk height of 2.5cm^3/g
above, and the elongation of the composite yarn at a load of 1 g/D is 7%
A sewing thread characterized by: (2) The sewing thread according to claim (1), wherein the composite thread has a structure in which the thermoplastic synthetic fiber multifilament thread is the core thread and is integrally bonded to the sheath thread by continuous entanglement. (3) The sewing thread according to claim (1), wherein a plurality of composite threads are bonded together by heating.