JPS63165513A - Direct spinning and drawing of polyamide fiber - Google Patents

Abstract

PURPOSE:To obtain the titled uniform and high-quality fiber of both high strength and elongation, by cooling a plural of spun yarns respectively in a separate manner, imparting lubricant and drawing without crossing with one another followed by superposition and integration with an air nozzle, and then further drawing on heating and heat-treating at relaxed state. CONSTITUTION:In the direct spinning and drawing of polyamide fiber (e.g. nylon 6), melt spinning is carried out using an equipment with a plural of delivery parts 1, 1', spinnerets 2, 2' and cooling zones 3, 3', respectively, to cool the corresponding spun yarns Y, Y' in a separate manner, at the cooling zones 3, 3', respectively, impart said yarns with a lubricant at oiling sections 4, 4', respectively, followed by winding on a set of rollers 5, 5', 6, 6' without crossing the monofilaments of said yarns with one another and then drawing by a factor of 2.6-4.2. Thence, part of the monofilaments forming respective said yarns are mutually superposed followed by integration while interlacing respective said yarns with an air nozzle 7 followed by successively winding on a set of rollers 8, 8', 9, 9' in this order to make a drawing on heating and heat-treatment under relaxed state, thus obtaining the objective fiber Y''.

Description

Detailed Description of the Invention <Industrial Application Field> The present invention relates to a method for direct spinning and drawing of polyamide fibers, and in particular, a method for directly spinning and drawing polyamide fibers. The present invention relates to a spinning and drawing method.

<Prior Art> Recently, in order to improve the productivity of polyamide fiber miscellaneous materials, so-called direct spinning and drawing methods, which directly connect the spinning process and the drawing process, have been actively developed.

14. Regarding the direct spinning and drawing method of high-strength polyamide fibers used for tire cords, belts, ropes, etc., for the purpose of improving operability and stabilizing quality, the drawing is carried out in multiple stages, and the drawing distribution ratio and 7JL during drawing are A method of regulating thermal temperature is disclosed in Japanese Patent Publication No. 17803/1983.

Further, for the purpose of improving the convergence of the yarn, Japanese Patent Publication No. 3847/1983 discloses a method in which split and drawn yarn is entangled with air just before a winder and then doubled.

<Problems to be solved by the invention> The above-mentioned Japanese Patent Publication No. 55-17803 discloses that after melt spinning, the yarn is preheated to 35° C. to 60° C. It is characterized by performing a first stage of drawing at a draw ratio, then preheating the yarn to 40°C to 100°C and performing a second stage of drawing, and then heat treatment at 140°C to 200°C. This direct spinning/drawing method is effective in improving operability and stabilizing quality when the cutting strength of the resulting polyamide fiber is on the order of 99/d, but in particular when the cutting strength is 10. When applied to the direct spinning/drawing method of high-strength polyamide fibers with CM7/d or higher, the quality is unstable and there are large variations in strength, elongation, and Worcestershire spots, and yarn breakage occurs frequently during spinning/drawing, making operations difficult. She was suffering from poor sexuality.

In addition, in the method of Japanese Patent Publication No. 48-3847, when producing high-strength polyamide fibers by direct spinning and drawing, although the effect of improving the limit drawing ratio is recognized, the cutting strength is 1.
Polyamide I which is 0.0g/d or more! The draw ratio required to produce l111c is high, and under yarns with high drawing tension, single yarn breakage occurs and the phenomenon of winding around the drawing rollers occurs frequently, which is a drawback, resulting in poor quality and operability. I was suffering badly.

The purpose of the present invention is to provide high-quality products with a cutting strength of 10 g/d or more.
Our objective is to provide a direct spinning/drawing method for obtaining high-grade polyamide fibers, which has very low yarn breakage and single fiber breakage during operation, and extremely good operability. Especially necessary.

Means and operation for solving the problems> The structure of the present invention is that in the direct spinning and drawing method of polyamide fibers, each of the plurality of spun yarns is independently cooled and oiled, and then each of the yarns is Without intersecting the medium threads between the rows,
The yarn is wound around the same roller group and stretched from 0.6 times to 4.5 times, and then, during the stretching process, the N1 yarn forming each yarn is manually twisted using an air nozzle as described above. A method for direct spinning and drawing of polyamide fibers, which comprises intertwining the yarns into one piece, then sequentially winding them around the same group of rollers, and subjecting them to heating drawing a''3 and relaxation heat treatment.

The polyamide fibers in the present invention refer to fibers made of nylon 6, nylon 66, or polyamides containing these as main components.

The present invention will be described in detail using the drawings.

The figure is a partial vertical cross-sectional schematic front view of a direct spinning and drawing apparatus for polyamide fibers according to the present invention. A plurality of yarns Y, Y- spun from spinnerets 2, 2- attached to a plurality of spinning units 1, 1' provided in a melt spinning machine are cooled independently by cooling units 3, 3, respectively. -, and is cooled by cooling air blown out in a direction substantially perpendicular to the running direction of the yarns Y and Y-;
Next, an oil agent is applied in the oil supply section 4.4-.

The spinnerets 2, 2 attached to the spinning parts 1, 1' as described above
The single yarn denier, heat, It is possible to reduce variations in history, etc., and obtain yarns Y and Y- made of uniform single yarns. If one q of yarn is attempted, a difference in viscosity is likely to occur particularly between the intermediate yarns forming the yarn, resulting in a yarn consisting of single yarns with large variations in quality.

The spun yarns Y and Y' are each passed through an independent cooling section 3.3'
By cooling the raw silk, interference between single yarns due to cold air and differences in cooling speed between raw silk can be minimized, and high quality yarn without cooling unevenness can be obtained.

The yarns Y and Y- cooled in the cooling portions 3 and 3' are oiled by independent oil supply portions 4 and 4-, respectively.
It is possible to minimize the overlap of a large number of single yarns that occurs when lubricating Y- and Y- all at once, and to obtain high-quality yarn without any spots on the lubricant 44.

After the yarns Y and Y'' have been cooled and applied with an oil agent f=J, they are guided to a drawing section, wound around a first roller group consisting of heated rollers 5.5', and then wound around a first roller group consisting of heated rollers 5. 6. It is wound around the second roller group consisting of 6-, and the 10th-
The stretching is performed depending on the circumferential speed ratio of the roller group and the second roller group.

In this case, the yarns Y and Y' need to be wound into the 10th-ra group so that they run parallel to each other without intersecting the single yarns.

This is because the single yarns forming the yarns Y and Y- overlap each other, so that the length of contact with the rollers 5.5' and 6.6' among the single yarns forming the yarns Y and Y- is Some yarns become short, and the single yarns are insufficiently heated by rollers 5.5- and 6.6', which inevitably causes stretching variations.
This single yarn may break during drawing, and there is a slight difference in the drawing point between yarns Y and Y-, which have different fat layers due to spinning, cooling, and oiling, and each yarn Y, Y'' It is important that both are drawn independently without being influenced by the threads of the thread.

Single filament breakage during drawing occurs not only due to the above-mentioned drawing variations but also more frequently when there are cooling spots and oil adhesion spots. The single yarn forming yarn Y and the single yarn forming yarn Y- are wound around a plurality of roller groups so as to run parallel to each other without crossing each other, and the stretching ratio is 0.6 times to 0.6 times. The yarn is drawn by a factor of 4.2 times, more preferably from 0.8 times to 4.0 times, and then, during the subsequent drawing, a portion of the single yarns forming each yarn Y, Y' are interlaced. A single yarn phase in which yarns Y and Y- are formed using the air nozzle 7! Intertwine 4 to make one.

The yarns Y and Y' were drawn by at least 0.61 g, so that the difference in the rolling history such as spinning, cooling, and oil application was eliminated, and the subsequent drawing was affected by the drawing process. Never. Therefore, a portion of the single yarns forming yarns Y and Y- can be overlapped before being intertwined and integrated using an air nozzle.

If the single yarns Y and Y' are not superimposed,
After being intertwined with the V-nozzle and made into a single piece, yarn cracking may occur, and the middle threads forming the yarns Y and Y- may become randomly entangled with the phase 1j and not be made into a single piece. Therefore, a portion of the single yarns are overlapped before being intertwined and integrated using an air nozzle. If the yarn Y and Y are not part of the single yarn here,
- If all are superimposed V, then 0 due to this vehicle tension U
．． During stretching in a stretching range of less than 6 times or less than 2°618, the single yarns forming yarns Y and Y- overlap, which is not preferable.

The yarns Y and Y- are drawn at least 0.6 (8) without crossing the single yarns forming each yarn, and then during the subsequent drawing, the single yarns forming each yarn are drawn. After adjusting a part of the air, in order to guide it to the air nozzle,
The roller surface of the second roller group is satin-finished, and
By adjusting Nelson Kakumaro and the upper limit of the yarn tension as the draw ratio increases, the density of the yarn to the roller increases and the width of the yarn increases, but the yarn Y, Y- Until the yarn is drawn to at least 0.6 times, it is wound around the second roller group without intersecting the single yarns forming each yarn, and then the circumferential speed of the second roller group and the second roller group is Near the exit of the yarn path of the second roller group, where drawing begins between the third roller group, which rotates at a higher speed than can. That is, after the stretching of at least 0.6 times is completed near the entrance of the yarn path of the second roller group, the second stretching is completed near the exit of the yarn path of the second roller group.
Under the influence of the third roller group, which rotates at a higher speed than the circumferential speed of the second roller group, the yarn slides on the surface of the second roller, creating a condition in which new stretching begins. When adjusting the Nelson angle of the second roller and stretching i? The density of the yarn to the roller increases due to the yarn tension on the back as the thread rate increases, and the expansion of the yarn width causes the second
The yarn width and the inter-yarn width between yarns Y and Y- gradually become narrower from the population of the yarn path of the roller group toward the exit of the yarn path.
A state can be created in which a portion of the single yarn forming yarn Y and a portion of the single yarn forming yarn Y- are overlapped near the exit of the yarn path of the second roller group. It is then wound around a third roller group consisting of heated rollers 8, 8-. The circumferential speed of the third ``1-R'' group is lower than the circumferential speed of the second roller group. (The stretching ratio of the yarns Y and Y' is 0.6 times)!If the air nozzle 7 performs doubling and entangling between the single yarns, the overlap of the single yarns increases and the roller The yarn body vibrates in the outer circumferential direction of the yarn body, increasing stretching unevenness, which causes yarn breakage during subsequent stretching.Furthermore, after the stretching ratio of yarns Y and Y- exceeds 4.2 times, When the air nozzle 7 performs doubling and entangling between single yarns, since the yarns Y and Y- have high tension, the amount of work 12- supplied to the air nozzle 7 increases significantly, and the noise caused by the air is significant and the work environment becomes difficult. This is not preferable as it not only worsens the situation but also tends to cause single yarn breakage and breakage of the yarn body before reaching the air nozzle 7. However, by intertwining each single yarn, the stress during drawing is not concentrated on a specific single yarn, and the occurrence of single yarn breakage can be minimized or eliminated. In the case of 5111 yarn entanglement, the single yarn runs without being wrapped around the rollers, and the operation can be performed smoothly without causing yarn breakage.

The yarn YD wound around the rollers 8, 8' is then wound around a fourth roller group consisting of heated rollers 9, 9-. The circumferential speed of the fourth 11-ra group is lower than the peripheral speed of the third Ll-ra group, and the yarn Y'' is relaxed and heat-set during this time, and then wound ”). Another roller group is provided between the first roller group consisting of rollers 5 and 6 and the second Ll group consisting of rollers 6 and 6. 3rd consisting of 8-
Laura J! Eight other rollers are provided between 'I' and the fourth roller group consisting of rollers 9 and 9.

In addition, the oil supply sections 4, 4' may be provided with other oil supply devices for multistage oil supply, and a plurality of knee nozzles may be used for doubling yarns and interlacing single yarns in the air nozzle 7. You can go. 10.10' is Shuju [1-ra, 11.
11- indicates ten thousand [1-la] 1゜〈Example〉 Examples 1 to 5 and 3 and Comparative Example 1.2) Nylon 6 with a Φ limiting viscosity of 3.80 was pore-formed using the apparatus shown in the figure. Melt spinning was performed at a discharge rate of 1430 g/min from several 306 nozzles, and the jq-shaped plurality of spun yarns Y, Y- were independently oiled with oiling rollers 4, 4-, and then rotated at a circumferential speed of 400 m/min. Heated roller group 5.
A group of rollers 5.5- is wound with each yarn Y, and the single yarn between Y- is wound without crossing and run in parallel, and then the peripheral speed is heated.
Set to 0.4 to 4.3 times of 5', from 120°C
By adjusting the Nelson angle of the roller groups 6, 6' heated to Y, Y
- wind the single yarns between the roller groups 6, 6- without crossing each other, and then each A part of the single yarn between the yarns Y and Y'' is overlapped and wound, and then the air nozzle 7
And pressure J is 6K! j/crIi, flow rate is 400!
/min of air to make the yarns Y and Y'' intertwine and intertwine and integrate them, and then the peripheral speed of the heated roller group 5, 5' is 5.35 times or more. The circumferential speed was set to be 5.40 times higher, and the circumferential speed was set to 0.98 inch of the circumferential speed of the roller group 8, 8-, which was heated to 195°C. 8 and heated to 210'C, roller groups 9, 9- were rolled, subjected to relaxation treatment, and then wound up with a winder.

The results obtained were shown in the table.

As can be seen from the table, the yarn produced under conditions of a) stretching ratio of 0.6 to 4.2 times the yarn before doubling and entangling has high strength and elongation, small Worcestershire spots, and medium The yarn had high strength and elongation, and the single yarn had small variations in strength and elongation and was of high quality.

J: The number of single yarn breakages and yarn breakages during operation was small, and the spinning performance and operability were extremely good.

In particular, the drawing ratio of the yarn before doubling and interlacing of single yarns is 8 or 0.8.
The yarns produced under the conditions of 4.0 to 4.0 times had higher strength and elongation, a smaller quality variation, and good spinning properties.

On the other hand, the stretching ratio of the yarn before doubling and single yarn entanglement is 0.6
(Cows with rows less than 2' or more than 4.2 times
The produced yarns (Comparative Example 1.2) all had lower strength and elongation than Examples 1 to 5, had large Worcestershire spots, and
The strength and elongation of the yarn are low, and the strength and elongation of the single yarn are highly variable, making it impossible to obtain a product of the highest quality.Furthermore, single yarn breakage and thread breakage occur frequently, resulting in poor spinning performance and operability. The situation was not satisfactory.

The strength and elongation of the single yarn are determined by dividing the yarn into 306 single yarns, selecting any 50 yarns among them, and measuring the cutting strength and elongation of each yarn. This is the average value of the measured values. Further, the medium yarn strength CV (%) and the single yarn elongation C■ (%) are values representing the magnitude of dispersion in which the average value (x) and the standard 8 difference σ are related by the following formula.

Example 6 Heated rollers 5, 5 in addition to the device used in Example 1
Another heated set rotating at a speed of 1.0518 of the circumferential speed of the roller group consisting of rollers 5 and 5- is roughly between the cola group and the roller group consisting of rollers 6. A group of rollers was installed to draw the yarn in multiple stages before doubling and interlacing. Further, the peripheral speed of the roller group consisting of rollers 6 and 6- is 3 times the peripheral speed of the roller group consisting of rollers 5 and 5'.
The conditions for each strip 1'1 were all the same as in Example 1, except for multi-stage stretching as described above.

1 by applying heating multi-stage stretching and relaxation heat treatment under IIL conditions.
Item 71 of yarn made by II has a fiber length of 1.875 d, a strength of 10.259/d, an elongation of 20.6%, and a Worcestershire spot number 5.
0%, single yarn strength 10.83SF/d, single yarn strength fQcV'
1.25%, single yarn elongation 24.4%, single yarn elongation CV8.8
At 5%, it is possible to obtain a yarn of even better quality than Example 1.
During continuous operation for 2/1 hour, the number of thread breaks during continuous operation was 0.75, which is extremely good.69 times.

Comparative Example 3 Using the apparatus of Example 1, melt spinning, cooling and oiling were carried out in the same manner as in Example 1, and heated t-roller group 5,
5-, a group of rollers 5, in which the single yarns between each yarn Y, Y'' are wound without crossing each other and run parallel to each other, and then the peripheral speed is heated;
5- and heated to 120°C.The middle thread between each yarn Y and Y' is wound around the 6°6- set of rollers without overlapping at all, and then the air nozzle 7 is used to apply pressure. is 6
Kg/ci, air with a flow opening of 4001/min was blown onto each yarn Y using only the air nozzle 7.

Attempts were made to integrate Y- by doubling and entangling single threads, but the threads broke and could not be integrated. Further, even if the pressure flow rate of the air nozzle 7 was changed, yarn breakage could not be prevented.

Effects of the Invention> According to the present invention, the quality of each single yarn forming the yarn has small variations, is extremely homogeneous, has particularly high strength and elongation, has small Worcestershire spots, and has no single yarn breakage. High quality yarn can be obtained.

In addition, there is little occurrence of thread breakage during drawing and heat treatment of the thread, which significantly improves operability.

[Brief explanation of the drawing]

The drawing is a partially vertical cross-sectional schematic front view of a direct spinning and drawing apparatus for polyamide fibers according to the present invention. 1.1′...Spinning section, 2,2-...
・・・・・・Base, 3.3-・・・・・・Cooling part, 4, 4-・・・・・・Oil supply part, 5.5", 6
．． 6-18.8-19.9-...Roller, 7...Air nozzle, 10.10"
...... Convergence roller, 11.11-...
...Guide roller, Y, Y', Y''...
...Yarn% I R'f Applicant Toshi Co., Ltd. drawings II.2 (no 1 change in white) Procedural amendment (method) Special ii' ``Director General Black Ro Akio 1 , Indication of the case Patent Application No. 315121 of 1985 2, Title of the invention 4, Date of amendment order March 31, 1988 (shipped 1
) 5. Drawings subject to amendment ・I

Claims (1)

[Claims] In the direct spinning and drawing method for polyamide fibers, each of the plurality of spun yarns is independently cooled and oiled,
Next, the single yarns between each yarn are wound around the same roller group without crossing each other, and stretched by 0.6 to 4.2 times. A polyamide fiber characterized in that after a part of the yarn is overlapped, the yarns are intertwined and integrated using an air nozzle, and then sequentially wound around the same roller group and subjected to heating drawing and relaxation heat treatment. Direct spinning and drawing method.