JPS59163430A - Manufacture of spun 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 The present invention provides a fiber bundle by cutting a fiber bundle, for example, a bundle of continuous fibers such as tow or multifilament, or a bundle of discontinuous fibers with a long fiber length such as wool or animal hair. The present invention relates to a method for producing spun yarn that is directly spun in one step.

More specifically, the fiber bundle is divided into a plurality of fiber bundles while or after being brought into contact with a cooling medium of -5°C or less, and the fiber bundle is cut by applying a drawing force and/or a shearing force to the fiber bundle. The present invention relates to a method for producing a spun yarn, in which a plurality of discontinuous fibers are formed into a bundle, which is then continuously supplied to each spindle of a spinning frame for spinning.

A method for producing spun yarn from raw materials in one step is to feed a group of staple fibers to a card, divide the carded web into fiber bundles, and feed the fiber bundles to an open-end spinning frame having a rotating spinning chamber. , Japanese Patent Publication No. 50-26656, Japanese Patent Publication No. 52-27727, etc. have been proposed.

However, since these go through a carding process, it is not possible to create highly uniform fiber bundles in the carding process, which causes neps, hooks, etc., and because the parallelism of the single fibers is poor, thread breakage occurs in the spinning machine. and the spun yarn has many yarn irregularities and yarn defects (spun yarn of good quality cannot be obtained).

■ Furthermore, even if the carding process is lengthened and a fiber opening device with a combing function is installed, such as with metallic wire, the above-mentioned drawbacks of the carding method will not be improved much, and the installation area will become too large, resulting in structural problems. It is also unsuitable for low-volume, high-mix production systems.

(2) Furthermore, when brittle fibers, weakly crimped fibers, or fibers with little interfiber stiffness are supplied, there are problems such as fiber breakage and web sagging, and there are restrictions on the fibers that can be used and their forms.

■ In the raw cotton production process, it is necessary to produce short fibers by cutting the fibers into lengths that match the purpose of spinning.

■ Shrinkage cannot be imparted to the spun yarn during the spinning process.

There was such a problem.

On the other hand, as a method for producing spun yarn in one step from a bundle of continuous fibers such as tow or multifilament, the fiber bundle is fed to two sets of rollers with different surface speeds, and each single fiber making up the fiber bundle is drawn. A method is known in which spun yarn is produced by cutting, drafting to a predetermined weight, and then heating. However, since this method cuts by applying a drawing force at around room temperature (20°C), the fibers are cut with large plastic deformation, resulting in residual strain inside the fibers, making it difficult to obtain spun yarn with low shrinkage. do not have.

Since tension cutting is carried out on a spinning machine in a viscoelastic range and at high speed, the tips of single fibers are bent and curled during cutting, are easily disturbed by air currents, have poor thread unevenness, and often break.

Since the crimp of the θ cut layer and single fibers disappears, the surface of the spun yarn becomes fluffy.

In addition, when connecting the direct spinning method and the open-end spinning method, in the conventional direct spinning method, the fibers are cut after being sufficiently plastically deformed, so the crimp imparted to the raw cotton disappears, and the fibers are cut by the opening roller. Winding and opening were poor, making spinning difficult. On the other hand, there is a method described in Japanese Patent Publication No. 48-25372, in which a tension-cut sliver is crimped using a pair of heating gears. but,
It is difficult to apply sufficient crimp with this method, and even if it were possible, the crimp would be such that the sliver would fold, so the single fibers would be restrained by the crimp and the single fibers would become misaligned. Even if the fibers are split and opened later using a fiber opening roller, it is not sufficient and yarn breakage and yarn unevenness increase.In addition, this method not only cannot sufficiently alleviate the shrinkage that has occurred, but also causes non-uniformity. There are many problems such as increasing the number of people.

In addition, as a method for compressing a bundle of continuous fibers and supplying it to an open-end spinning machine having a rotating spinning chamber,
There is a method described in Japanese Patent No. 3611. In this method, a bundle of continuous fibers is cut by a pressure roller such as a cutter immediately before the supply pipe of an open-end spinning machine, and then the fibers are separated by the airflow generated by the rotation of the rotating spinning chamber. In the case of fibers that have been compressed, the ends of the fibers are not separated one by one, and there are many yarn breakages, yarn unevenness, yarn defects, etc., and spun yarn with good quality cannot be obtained.
ゝ0 The present invention provides a method to solve the drawbacks of such conventional methods, and in addition to being free of the above drawbacks in the spinning process, it is possible to produce spun yarn with a low to medium shrinkage percentage, and is an extremely excellent method. The present invention provides a method for producing quality spun yarn in one step.

The present inventors previously proposed a method for manufacturing a bundle of discontinuous fibers with low shrinkage from a bundle of continuous fibers in Japanese Patent Application No. 56-1574.
The method described in the specification No. 2 was proposed. In this method, the fiber bundle is cooled to below -5°C and stretched near the elastic region where the elongation is extremely low (hereinafter referred to as the frozen stretch cutting method). It is possible to efficiently produce bundles of discontinuous fibers with excellent parallelism due to shrinkage, as well as bundles of discontinuous fibers with low shrinkage and excellent parallelism, and whose cut waste also has crimps. It is extremely effective.

For this reason, it is possible to supply fiber bundles with excellent parallelism and spreadability to the spinning process, which is unimaginable with conventional methods, making it possible to produce spun yarn with excellent spinnability and quality. Became.

In the conventional method, when the pre-spinning process and the spinning machine were connected, due to the difference in production volume, it was limited to machines with high spinning speeds such as open-end spinning machines, and when producing large counts.
In the method of the present invention, the speed of the pre-spinning process can be changed freely, and the slower the speed, the smaller the cooling device and the smaller the installation area.

In addition, since bundles of continuous fibers such as tow can be used, the method is excellent as a method for producing spun yarn for small-lot, high-mix production.

That is, in the present invention, a fiber bundle cooled to below -5°C is divided into a plurality of fiber bundles using a divider and cut.
It is a device that is continuously supplied to an existing spinning machine, and is characterized by producing spun yarn in one process from fiber bundles such as tow and multifilament.

As the fiber bundle of the present invention, a bundle of continuous fibers such as tow or multifilament is generally used. Continuous fibers include polyamide, polyester, polyacrylic, polymodified acrylic, polyurecne, polyvinyl chloride,
Synthetic fibers such as polyvinyl alcohol-based fibers, semi-synthetic fibers such as acetate-based fibers, recycled artificial fibers such as rayon and cupra, etc. are used, and acrylic synthetic fibers are particularly preferably used. As a bundle of continuous fibers, the fineness of single fibers is 01
Multifilament yarns ranging in total denier from 30d to 2,000,000d consisting of ~100 denier tdl are commonly used. Furthermore, it can be applied to a mixture of the above-mentioned continuous fiber bundle and a fiber bundle made of short fibers, or a mixture with other fibers. It can also be applied to the case where a discontinuous fiber bundle having a long fiber length such as wool or animal hair is cut into short lengths.

The lower limit of the temperature of the cooling medium used in the present invention is up to absolute zero, but this causes problems in the cost of the medium used and the equipment, so a temperature of -5°C to -195°C is preferred.

Any cooling medium can be used as long as it has a temperature of -5° C. or lower, and solid, liquid or vaporized gases such as ammonia, carbon dioxide, air, oxygen, nitrogen, fluorocarbon refrigerants, and cryogens can be used. It is also possible to use an electrical cooling method.

The time of contact with this cooling medium varies depending on the type of fiber, feeding method, type of medium, temperature, etc., but generally 0.1
A time period of about seconds to 100 minutes is used.

The method of contact with the cooling medium is not particularly limited, but there are methods such as bringing the fiber bundle into contact with the surface of the cooling medium, passing the fiber bundle through a gas atmosphere or liquid, and dropping the cooling medium onto the fiber bundle. .

For cutting, single fibers are cut by applying drawing force and/or shearing force to the fiber bundle while or after contacting the fiber bundle with a medium at -5° C. or lower. There is no problem in using other cutting forces in addition to these.

In addition, the patent application No. 57-1756 previously proposed by the present inventors
As described in the specification of No. 50 (1) After giving a flavour-shaped bag to a single fiber with an opening, it is possible to cut the single fiber by applying a drawing force and/or a shearing force (＼0 Cooling zone It is preferable that the fiber bundle to be supplied to the fiber bundle is uniform in thickness while dividing the single fibers uniformly into a constant width.

The division is carried out while or after the fiber bundle is brought into contact with a medium at -5°C or lower. In the case of multiple multifilaments, it is sufficient to simply provide multiple guides, but in the case of fiber bundles with a very large number of fibers such as tows, The fibers are cooled to -5° C. or below, and the diagonal single fibers are cut to a predetermined width using a divider while the elongation is very low (1) and divided into a plurality of fiber bundles. At this time, the fiber bundle is cooled and the rigidity of the six single fibers increases, so there is less fusion and disturbance of the fiber bundle by a cutter, etc., and it can be easily divided. In addition, the cut layer or fleece state may be divided by a dividing roller or the like.

In the present invention, since the tension cutting and spinning are separated, cooling and cutting can be concentrated in one place, which not only simplifies the structure of the cooling device but also reduces cooling costs. On the other hand, in terms of quality, the speed in the tension cutting area is slow (and the number of fiber bundles that make up the fiber bundle increases, so there are fewer spots caused by bounce of single fibers and turbulence caused by airflow during tension cutting. By separating the tension cutting and spinning, it is possible to increase the speed of the spinning machine.

In this way, the divided fiber bundles are fed to the existing spinning machine by the feed rollers. Further, after being divided, the fiber bundle may be passed through rubbing rollers to improve the cohesiveness of the fiber bundle before being fed to an existing spinning machine.

Spinning machines include ring spinning machines, rotor-type open-end machines, air vortex open-end machines, bundle spinning method, air vortex core yarn method, adsorption heating method, self-twisting method,
Although various spinning machines such as a twistless spinning method can be used, a spinning machine with the highest possible productivity is preferable.

Next, the present invention will be explained with reference to the drawings. FIG. 1.3 is a process diagram showing an embodiment suitable for carrying out the present invention. 1st
In the figure, a fiber bundle 1 whose thickness is adjusted while dividing single fibers uniformly into a constant width is fed into a low temperature chamber 7 by a back roller 2 and a delivery roller 8 of the low temperature chamber 7. The delivery roller 8 seals the inlet of the cryostat 7 and compresses the outside air contained in the fiber bundle 1. At this time, by overfeeding the take-up roller 9 at the exit, cooling efficiency can be improved and fiber breakage due to fiber shrinkage in the low temperature chamber 7 can be prevented.

The fiber bundle 1, which has been sufficiently cooled by meandering through the low-temperature chamber 7 by a rotating roller 10, is compressed of cold air by a take-up roller 9 that seals the outlet. The fiber bundle 1 is brought into contact with a cooling medium at -5° C. or lower in a low-temperature bath 7 to increase the stiffness of the fibers and make them less elongated, after which a drawing force is applied by middle rollers 3 and break rollers 4. The fibers are cut to form a bundle of discontinuous fibers, and in this state are divided into a plurality of fiber bundles 12 using a cutter 11.

Next, the sliver is divided by the guide 12 and stapled to a predetermined weight and staple diagram by the front roller 5, then the tube 14 improves the convergence of the sliver, and the delivery roller 6 is used to transfer the sliver to the adsorption heating spinning machine 15. It is supplied to each spindle to form a spun yarn 16.

Figure 2 is a plan view of Figure 1 of the spear. Figure 3 shows the exit of the cryostat, after the fiber bundles 1 are divided into multiple fiber bundles 1 by the cutter 11.
The discontinuous fibers are cut into bundles and continuously supplied to each spindle of a rotor-type open-end machine 17 to produce spun yarn.

Example 1 A tow of 560,000 denier made of polyacrylic synthetic fiber 3D was placed in the apparatus shown in Figure 3 and spun under the following conditions.

Crimped state of single fiber Number of crimp 12 (K/I''/f) Degree of crimp 12 (%) Overfeed rate 5 (%) Cooling medium
Atmosphere temperature in nitrogen gas cryogenic chamber -100 (℃) Open-end condition Spinning speed 100 (m/min)
As a comparative example, the tow was cut at room temperature (20° C.) using a direct spinning method to impart crimps, and then fed to an open-end spinning machine and spun under the same conditions.

Furthermore, the following table shows the results of comparing the physical properties of the obtained sliver obtained by supplying the same staple fiber (3D canted to a 6 mm square) to the 7 Lasoto card.

In the conventional direct spinning method, the fibers are sufficiently plastically deformed at room temperature (20° C.), so that the crimp in the cut layer disappears.

The onset of contraction is too large and a low contraction rate cannot be obtained. Furthermore, there are problems such as a decrease in the hook strength and elongation of the single fibers. On the other hand, the sliver obtained by the method of the present invention not only has a low shrinkage rate but also maintains its original crimp. It was possible to produce excellent sliver.

In addition, the above sliver was continuously fed into an open-end spinning machine, and the process performance and spun yarn were compared.

As a result, since there is no crimp in the direct spinning method, it is difficult to open the fibers.
There were spinning defects such as wrapping around the opening roller. Further, even if the yarn is crimped using a stuff ink box, only a spun yarn with a high shrinkage rate and extremely fluffy yarn can be obtained.

In addition, in the card method, there are more defects such as thread breakage and yarn irregularities than defects such as U%, parallelism, and neps of the sliver, and spinnability,
The quality was also poor. In contrast, the method of the present invention does not have the above-mentioned drawbacks such as winding, yarn breakage, yarn unevenness, yarn defects, fuzz, shrinkage rate, etc., and is capable of producing spun yarn with good spinnability and quality. It became.

The present invention thus manufactures a bundle of discontinuous fibers by contacting with a cooling medium of -5°C or lower, and then continuously supplies the fibers to each spindle of a spinning frame to form a spun yarn. 1) By changing the temperature of the cooling medium, it is possible to produce a spun yarn with any shrinkage rate from low to medium shrinkage.

2) The cut layer also has the same crimps as raw cotton, and has excellent parallelism and U%, resulting in good spinning properties and quality of the spun yarn. be.

3) The installation area is small and the structure is simple, making it suitable for low-volume, high-mix production.

4) Even when dividing with a cutter, the fibers can be easily divided without fusion or disorder.

5) Also, since it has excellent parallelism, opening properties, and U%,
In particular, it can be continuously supplied to spinning machines that do not have a fiber opening mechanism.

[Brief explanation of drawings]

Fig. 1 is a side view showing the process of implementing the present invention, Fig. 2 is a top view of Fig. 11, and Fig. 3 is a side view showing another example of implementing the present invention. For patent [Asahi Kasei Industries, Ltd.]

Claims (1)

[Claims] While or after bringing the fiber bundle into contact with a medium at -5°C or lower, the fiber bundle is divided into a plurality of fiber bundles, and the fiber bundle is cut by applying a drawing force and/or a shearing force to the fiber bundle, thereby producing a plurality of fiber bundles. A method for producing spun yarn, which comprises forming a bundle of discontinuous fibers, and then continuously supplying the bundle to each spindle of a spinning frame for spinning.