JPS5921982B2 - Multifilament drawing method - Google Patents

Description

[Detailed description of the invention] The present invention relates to a method for drawing multifilaments.

More specifically, the present invention is a method for drawing a multifilament, which improves the drawing performance by intertwining the tips of one or more broken filaments generated in the process of drawing the multifilament with an arbitrary group of filaments. .

Conventionally, multifilaments are knitted and woven into fabrics in various forms such as flat yarns or textured yarns, and are usefully provided in various fields of use such as clothing and industrial use.

This multifilament is usually obtained by drawing it at several times the magnification after spinning. This is a big problem when producing it industrially.

In addition, if a multifilament has one or more broken filaments, it may cause yarn breakage when it is temporarily warped, or it may cause problems such as yarn breakage or bunching when warping, resulting in poor high-order processability. This is a significant loss.

For this reason, ■ a method of dispersing titanium oxide in synthetic polymers (
(Japanese Patent Publication No. 28-1208), ■ Method of adding twist to undrawn yarn and drawing it (Japanese Patent Publication No. 39-22675), ■
A method of stretching the yarn introduction part of the stretching roller by satin finish (
(Japanese Patent Publication No. 42-19492), ■Method for regulating yarn feeding tension of undrawn yarn (Japanese Patent Publication No. 45-32778)
Other methods have been proposed to prevent the generation of one or more broken filaments, such as preheating the yarn or two-stage stretching, and thereby preventing multifilament yarn breakage.

However, using any of these methods, it is extremely difficult to effectively prevent the occurrence of broken filaments and to produce a multifilament with no broken filaments.

Therefore, for processing and application fields where the presence of broken filaments is extremely disliked, only multifilament drawn packages that are virtually free of broken filaments are provided, resulting in poor yields and the occurrence of broken filaments. There is a problem in that each package must be checked and selected in detail.

The first object of the present invention is to prevent these conventional drawbacks, namely, the breakage of one or more filaments that occurs during the process of drawing multifilaments, and the yarn breakage caused thereby, without using complicated equipment or methods. It is an object of the present invention to provide a multifilament drawing method that provides high drawing results.

Furthermore, the second object of the present invention is to provide a multifilament with good process passability, in which troubles such as yarn breakage are less likely to occur in the process of temporarily twisting the multifilament, warping, twisting, weaving, or high-order processing such as a knitting ring. To provide filament.

That is, when a multifilament is stretched between arbitrary rollers, the present invention sprays a fluid onto the multifilament in an area in front of the stretching rollers where stretching has substantially finished and where stretching tension is applied. This multifilament drawing method is characterized by intertwining the ends of the broken portions of one or more filaments with an arbitrary group of filaments.

The multifilament drawing method according to the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a schematic diagram showing a preferred embodiment of the multifilament drawing method of the present invention, in which the undrawn yarn 2 unrolled from the undrawn yarn cheese 1 is fed to a pair of guides 3 and 3'. The yarn is supplied to yarn rollers 4, 4, where stretching is substantially completed at a stretching pin 5, and then sent to a stretching roller 7 having a dividing roller 8 arranged thereon.

At this time, a fluid ejecting device 6 is disposed in the region where the stretching tension is acting between the stretching pin 5 and the stretching roller 7, and fluid is jetted so that the tip portions of the broken filaments generated during stretching are divided into arbitrary filament groups. without winding the broken filament around the drawing roller 7, the broken filament is wound onto the drawn yarn pirn 11 via the guide guide 3/, / ring 9 and traveler 10.

Here, the fluid ejecting device of the present invention is not particularly limited, and for example, Japanese Patent Publication No. 36-12230, Japanese Patent Publication No. 49-411
It is possible to use the various spraying devices disclosed in Japanese Patent No. 31, and the latter spraying device is particularly preferred since it facilitates threading.

Further, from the viewpoint of cost, it is preferable to use compressed air as the fluid for injection.

Furthermore, the entanglement mentioned here does not only mean non-electrical entanglement as disclosed in FIGS. 25 and 26 of Japanese Patent Publication No. 37-1175, but also the entanglement that is strongly connected in a loop shape. Including those who are

In addition, the strength of the entanglement at the broken filament part is preferably such that when a hook of weight equivalent to the single yarn denier is inserted into the middle of the multifilament yarn bundle and dropped, it stops at the entangled part. It is not limited to this.

According to the present invention, the broken filaments are not wound around the drawing roller in order to firmly intertwine the broken filaments generated during drawing with an arbitrary group of filaments.

This eliminates the phenomenon of yarn breakage caused by broken filaments wrapped around the drawing roller, which was considered a drawback of conventional drawing methods, and improves yield. Good yarn properties and workability can be obtained.

A peculiarity of the method of the invention is that the multifilament is injected with fluid in the region before the drawing rollers, where the drawing has substantially ended and is under the action of the drawing tension.

As a result, only the tip of the broken filament that occurs during drawing is firmly intertwined with an arbitrary filament group, but there is virtually no entanglement of filaments in the filament group other than the intertwined part, and the entire multifilament is It does not provide excessive focusing.

The stretching tension for this purpose is preferably 0.7 f/d or more.

In addition, a method of manufacturing a non-electric close multifilament interlaced yarn by injecting a fluid onto a multifilament and intertwining arbitrary groups of filaments constituting the multifilament with each other due to the turbulent action of the fluid is described, for example, in Japanese Patent Publication No. 36-12.
It is already known from the publication No. 230.

However, the purpose of this method is to uniformly impart high-frequency entanglement to the entire multifilament, and the tension of the yarn when injecting fluid during the spinning or drawing process is extremely low, preferably 0. .25/d or less, which is significantly different from the purpose and means of the present invention.

Note that drawing in the present invention refers to not only the case of drawing so-called undrawn yarn with low molecular orientation, but also the case of drawing so-called pre-oriented yarn with relatively high molecular orientation, and the drawing directly connected to spinning. Including all cases.

In this case, any type of stretching machine such as a draw twister or a draw winder can be used.

Further, the method for manufacturing a multifilament of the present invention includes the first method for producing a multifilament.
The method of drawing with a system of yarn feeding rollers, drawing pins, and stretching rollers as shown in the figure is either a system of yarn feeding rollers, heating plates, and stretching rollers, or a system of yarn feeding rollers, preheating rollers, and stretching rollers. It can be applied to all conventionally known methods.

In addition, when stretching is performed in multiple stages, one or more injection devices can be disposed in front of each stretching roller.

These seven multifilaments used in the present invention include filaments made of synthetic polymers such as polyester, polyamide, polyacrylonitrile, and polyolefin, or filaments made of such polymers and a third component copolymer, or filaments made of semi-synthetic polymers; Examples include recycled fibers.

In particular, in the case of polyester, low degree of polymerization polyester with an intrinsic viscosity (measured in 0-chlorophenol at 25°C) of 0.55 or less, and modified polyester copolymerized with a third component other than ethylene glycol and terephthalic acid. The effect of the present invention is remarkable when using a filament consisting of.

The first characteristic of the multifilament obtained by the method of the present invention is that the tip portions of one or more filaments broken along the length of any group of filaments constituting the multifilament are irregularly and strongly intertwined. That is what we are doing.

Therefore, defects such as yarn pooling, bunching, tangling, and yarn breakage due to temporary twisting and well-known knitting and weaving operations, such as warping sizing, beaming, tube-wound weaving, and ironing during the knitting process, do not occur, and breakage does not occur. It exhibits excellent working and running characteristics that are substantially equivalent to multifilaments, which are substantially free of filaments.

A second feature of the multifilament obtained by the method of the present invention is that there is substantially no intertwining of filaments in areas where no broken filaments are present, and there is no excessive cohesiveness.

Therefore, even when the multifilament is subjected to temporary twisting, for example, it has a good texture mainly based on bulk.

Note that the above-mentioned broken filament refers to a filament in which one or more of the filaments constituting the multifilament is broken during drawing, and does not include a filament in which all the single filaments are broken.

According to the present invention, a broken portion of a filament that occurs during stretching can be intertwined with any group of filaments constituting the filament without substantially changing the cohesiveness of the drawn multifilament, and it is possible to intertwine the broken portion of the filament with any group of filaments constituting the filament, without substantially changing the convergence of the drawn multifilament. There is no winding of filaments and the yield of drawn yarn is improved, and workability after drawing and in higher-order processing steps is improved.

Further, since the intertwined portion of the multifilament is limited to a part where the broken filaments are intertwined, the obtained multifilament has a good texture.

The present invention will be explained in detail with reference to Examples below.

In addition, the first grade yield in the examples is the number of normal drawn yarn pirns in which no yarn breakage or broken filaments occurred during the process of drawing and winding a fixed amount (weight) of multifilament, expressed as a percentage. It is a value.

Example 1 In the apparatus shown in Fig. 1, titanium oxide was added to 0.5 wt%.
Contains intrinsic viscosity 0.66 (0-chlorophenol 25
An undrawn polyethylene terephthalate yarn (value determined at 120°C) was drawn at a draw ratio of 3.45 times through a metal drawing pin heated to 120°C, and at a drawing speed of 600 m/min, 75 denier was drawn. A drawn yarn pirn of 72 filaments was obtained.

In this case, the fluid injection device shown in FIG.
Similar to Publication No. 41131, φ1=1.5- φ2=0
．． 8van, 5W=0.05mm, A=130
The multifilament under a drawing tension of 1.2 S'/d was subjected to a fluid treatment in front of a drawing roller by using a device with an air pressure of 20 kg/ca.

When the obtained multifilament was warped using a general warping machine for textiles, the thread breakage was 1 per 1.2 x 107 m.
It was just an episode.

Comparative Example 1 In Example 1, yarns that were wound without fluid treatment and broken during the drawing and twisting process were excluded, and the pirn was drawn to a predetermined length by simply winding the broken filament with a draw roller. When warped in the same way as 1, it was 1.2
14 thread breaks occurred per i o7.

Example 2 In the apparatus shown in FIG. 1, an undrawn polyethylene terephthalate yarn containing no titanium oxide and having an intrinsic viscosity of 0.66 (value determined at 25°C in 0-chlorophenol) was
It was stretched at a stretching ratio of 3.3 times through metal stretching pins heated to 120°C, and at a stretching speed of 600 m/min.
A drawn yarn pirn of 5 denier and 72 filaments was obtained.

In this case, the fluid injection device shown in FIG. 1 is the same as in Example 1, and compressed air with an air pressure of 2.5 kg/crA is sent in to create a stretching tension of 1.5 kg/crA. IL? /d multifilament was subjected to fluid treatment in front of a drawing roller.

As a result, the primary yield of the drawn yarn pirn was extremely high at 98 inches.

On the other hand, the primary yield of the drawn yarn puir from the multifilament which was not subjected to the fluid treatment in the above process was as low as 90 cm.

Example 3 In the apparatus shown in FIG. 1, an undrawn yarn of nylon 6 with a molecular weight of 20,000 was drawn at a draw ratio of 4.5 times through unheated titanium oxide drawing pins to a length of 360 m /
A drawn yarn pirn of 24 filaments of 210 denier was obtained at a drawing feed rate of min.

In this case, the fluid injection device of the apparatus shown in FIG. 1 is the same as in Example 1, and the air pressure is 2.0 kg/c.
The multifilament with a drawing tension of 1.3 f/d was subjected to fluid treatment in front of the drawing roller by sending in ril compressed air.

As a result, the primary yield of drawn yarn purn was extremely high at 99.3%.

The supply roller and draw roller of the stretching machine were chrome-plated with a mirror finish.

Comparative Example 2 In Example 3, the nylon 6 multifilament was not subjected to fluid treatment and only normal stretching was performed.
The primary yield of the obtained drawn panin yarn was extremely low at 95.2%.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a preferred embodiment for obtaining the multifilament of the present invention. 1: undrawn yarn cheese, 2: undrawn yarn, 3, 3'. 3'': Guide guide, 4, 4': Yarn feeding roller, 5: Stretching pin, 6: Fluid injection device, 7: Stretching roller, 8: Split roller, 9: Ring, 10: Traveler-111: Stretched yarn pirn.

Claims (1)

[Claims] 1. When a multifilament is stretched between arbitrary rollers, a fluid is injected onto the multifilament in an area in front of the stretching roller where stretching has substantially finished and stretching tension is applied, and one or more of the fluids generated during stretching are A multifilament drawing method characterized by intertwining the tips of broken filaments with an arbitrary group of filaments.