JPH02139426A - Nylon flat yarn for combined knit fabric, its pirn package and production thereof - Google Patents

Abstract

PURPOSE:To obtain the subject yarn for the knitting of stocking without causing the end breakage, filament splitting and loop slipping, etc., by applying a small amount of a lubricant to a spun and cooled undrawn nylon yarn, orienting the crystal of the yarn by drawing, etc., and further applying a lubricant to the yarn. CONSTITUTION:A lubricant composed mainly of a smoothing agent (preferably having low kinetic friction coefficient to metal) is applied in an amount of <=1.2wt.% to a spun and cooled undrawn nylon yarn composed of 2-7 filaments. The undrawn yarn is subjected to crystal-orientation by drawing and/or high- speed take-up and further applied with a lubricant composed mainly of a smoothing agent to obtain the objective flat yarn attached with 1.6-2.4wt.% of the lubricant. The flat yarn is wound in the form of a pirn at a cross-angle of 1-5 deg. to obtain a pirn package.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention provides a nylon flat for inter-knitted fabrics which is useful for improving the knitting properties when inter-knitting with covered elastic yarns and the quality of green area products. The present invention relates to a yarn, its pirn package, and a method for manufacturing the flat yarn with good quality and productivity.

[Prior Art] Covered elastic yarns, which are made by covering polyurethane fibers with filament yarns such as nylon, have been used in stocking products due to their excellent elastic properties. When knitting this covered elastic yarn, it is generally practiced to cross-knit it with ordinary drawn nylon yarn (flat yarn) to improve the transparency and softness of the resulting stocking product.

The nylon flat yarn used for this cross-knitting has an elongation of about 30 to 50%, a strength of about 5 to 8 g/d, and a filament count of about 2 to 7 (mostly 3 ), a thin filament yarn with a yarn fineness of about 7 to 20 denier is used.

In addition, the other covered elastic yarn has an elongation of 300 to 60.
1000~4000t/about 0% spandex yarn
Covering yarn is generally used by winding the covering yarn with a covering twist number of approximately m.

[Problems to be solved by the invention] In this way, multiple types of yarns with completely different properties, especially elasticity properties, are knitted together, and some yarns have a large change in surface condition, while others are quite fine. Due to the fact that the low filament flat yarn of lA11i is subjected to inter-knitting, yarn breakage, yarn slack, etc. occur during the knitting process.
Filament cracking occurred frequently. As a result, problems such as knitting machine stoppages, stitch breakage, and stitch deviations occurred frequently, leading to decreased productivity and frequent defects such as holes and uneven stitches in the resulting products. . Defective products with defects such as holes or irregular stitches are either rejected during product inspection and become waste product, or require time-consuming repairs, resulting in a high number of defective products.
This results in an increase in the number of steps required for product inspection and repair processes, and an increase in product waste.

Above all, these troubles are caused by 2 problems as a flat yarn.
Or, when using a 3-filament yarn, this tended to occur particularly frequently.

Moreover, problems such as yarn breakage and fabric defects during alternating knitting tend to increase as the knitting speed increases, and these problems have become even more serious as stocking knitting machines have become faster in recent years. It was starting to become.

Therefore, the main object of the present invention (claims 1 and 2) is to prevent troubles such as yarn breakage and filament cracking and the occurrence of knitted fabric defects during this alternating knitting. By preventing troubles such as yarn breakage, the purpose is to improve knitting performance and quality of knitted fabric products, and improve product yield.

The main object of the method of claim 3 is to provide a yarn spinning method capable of producing the nylon flat yarn of claim 1 with good spinability and quality.

[Means for Solving the Problems] In order to achieve this object, the present invention provides a method in which 1.6 to 2.4% by weight of an oil agent mainly composed of a smoothing agent is attached to the fibers, and the number of filaments is 2. A nylon flat yarn for inter-knitted fabrics having the properties of: 2): After cooling the spinning, an undrawn nylon yarn with 2 to 7 filaments is coated with an oil agent mainly containing a smoothing agent at 1°2.
After adding less than 1% by weight, the crystals are oriented by stretching and/or high-speed drawing, and then an oil agent mainly composed of a smoothing agent is roughly applied, so that the amount of oil agent applied is 1.6 to 2.4% by weight.
A method for making nylon flat yarn for cross-knitted fabrics (
It consists of claim 3).

The amount of oil applied in the present invention is the amount of the active ingredient of the oil based on the weight of the fiber (5% by weight).

The nylon flat yarn for cross-knitted fabrics according to claim 1 comprises:
If the amount of the oil agent is within the range of 1.6 to 2.4% by weight, the yarn can be manufactured by a normal spinning method, such as a method of winding and stretching undrawn yarn, a direct spinning/drawing method, or a high-speed spinning method. Any type of nylon thread may be used. For example, melt spun,
After being cooled and lubricated, the undrawn yarn is taken off at a speed of about 500 to 1500 m/min and is once wound into a package.
Alternatively, a drawn yarn obtained by spinning the yarn by a method of drawing it to about 3 to 4 times without winding, or 400
Examples include oriented yarns obtained by taking off at a high speed of 0 m/min or more, winding up without substantially stretching, and crystallizing the yarn by this high-speed taking off.

In this way, the flat yarn of the present invention is a straight yarn that is crystal oriented to a certain extent, and has an elongation of, for example, 70%.
Below, strength 4. It is preferable to have a characteristic of Og/d or more.

The oil applied to this flat yarn may be an aqueous emulsion type oil or a non-water-containing oil as long as it is mainly composed of a smoothing agent. It is desirable to use a water-containing oil as the oil to be applied, and a non-water-containing oil as the oil to be applied to the yarn after drawing or high-speed take-off, from the viewpoints of yarn-spinning properties and quality stability.

As the smoothing agent, an ester smoothing agent, a low viscosity mineral oil, a polyether smoothing agent, a silicone smoothing agent, etc. are used. Among these, components with a low coefficient of kinetic friction against metals (
For example, a component having a dynamic friction coefficient of 0.25 or less with respect to a matte surface and metal at a speed of 1000 m/min is preferable. Moreover, it is preferable that the proportion of this smoothing agent to the total active ingredients of the oil agent is 60% by weight or more. Other ingredients such as antistatic agents and emulsifiers may be added. In addition, depending on the case, a trace amount of an antifoaming agent, preservative, or the like may be added in addition to the above.

This flat yarn is preferably wound into a pirn package with a winding angle of 1 to 5 degrees as claimed in claim 2, and this can be done, for example, by winding the yarn at an angle with a normal ring twisting machine. This can be done by

In addition, it is preferable that this pirn package has a slight twist to improve unwinding performance, but if the twist is too large, the twist will accumulate in the guides of each part during knitting, which will cause problems. It is preferable to have a soft twist of about 5 to 15 t/m, as this may easily cause knitting troubles due to the occurrence of knitting.

This nylon flat yarn for mixed knitted fabrics is a filament yarn composed of a few filaments (2 to 7 filaments), and the yarn fineness is preferably about 7 to 20 denier. Among these, in order to improve the transparency and softness of the obtained interwoven fabric, 3 to 5 filaments 1-
Preference is given to yarns with three filaments, especially three-filament yarns.

In addition, the polymer that makes up this flat yarn is nylon 6
, nylon 66, nylon 46, nylon 12, or a copolymer thereof.

The other yarn to be interknitted with the nylon flat yarn may be a normal covered elastic yarn made by wrapping a cover yarn in a single or double layer around a highly elastic yarn such as spandex yarn. As the cover yarn, a nylon multifilament yarn (drawn yarn or intermediately oriented yarn) of about 5 to 20 denier is usually used.

The cross-knitting of the nylon flat yarn and the covered elastic yarn may be carried out by a conventional method, for example, by using a stocking knitting machine with four yarn feeds and feeding the yarns alternately.

Furthermore, the yarn spinning method according to claim 3 is a suitable method for producing the nylon flat yarn for inter-knitted fabrics according to claim 1. This yarn spinning method involves spinning the yarn and winding it as an undrawn yarn, or subsequently drawing it without winding it.
Alternatively, it can be carried out by taking off the spun undrawn yarn at high speed or by roughly drawing it at a low ratio to obtain crystal orientation, and then winding it as intermediately oriented yarn or drawn yarn. At this time, the amount of oil applied at the stage before crystal orientation is 1.2% by weight or less,
In addition, it is necessary to apply the remaining amount of oil after crystal orientation.

The oil applied at the stage of undrawn yarn before crystal orientation (hereinafter referred to as drawing oil) may be any ordinary spinning oil mainly containing a smoothing agent, and even if it is a water emulsion type oil, it may not contain water. Although a type oil agent may be used, a water emulsion type oil agent is preferably used inside the shell. Then, it may be applied by the same lubricating means as in the case of ordinary spinning lubricants. Moreover, as the smoothing agent component, the same component (described above) as used for ordinary nylon fiber spinning oil may be used.

Further, the oil applied after crystal orientation by stretching or high-speed drawing (hereinafter referred to as post-stretching oil) is preferably a non-water-containing oil, but may be a water emulsion type oil.

Moreover, the above-mentioned oriented oil agent and the active ingredient may have the same composition or different compositions. The concentration of the oil agent is usually a straight oil agent consisting essentially only of active ingredients or a concentration of about 3% or more. The timing of refueling is after crystal orientation is achieved by stretching or high-speed drawing, and
It is sufficient that it is before winding up, and the oiling means may be guide oiling or roller oiling. As the smoothing agent, the same components as the above-mentioned pre-stretching oil agent can be used, but components with a low coefficient of dynamic friction such as ester-based smoothing agents are particularly preferred.

[Function] Since the covered elastic yarn has cover yarns wound on its surface in a direction substantially perpendicular to the longitudinal direction of the yarn, it has excellent unwinding properties.
Smoothness is poor, and tension unevenness during knitting tends to become quite large. However, when knitting only with this covered elastic yarn, yarn breakage is almost never caused due to its high elasticity.

On the other hand, nylon flat yarn for cross-knitted fabrics has a
A low filament yarn like a filament is used,
Moreover, it is used for knitting with a gentle twist of about 1 to 20 t/m. This formation usually has 500 to 1ooorp
The knitting machine is rotated at a rotational speed of about 1,200 m/min (the yarn speed is 500 m/min or more), and in some cases, the knitting machine rotation speed is about 1,200 m/min or more. Roughly speaking, this flat yarn is a completely straight yarn with no crimp, and moreover, it is a yarn with almost no cushioning properties against expansion and contraction.

A combination of these factors tends to cause a decrease in the filament cohesiveness of the flat yarn when the yarn is unwound from the package or when the various guides and knitting needles are rubbed on the knitting machine. The straining, sagging, and elongation that occur due to various stress fluctuations caused by knitting, and their recovery.
With the addition of phenomena such as twitching, the flat yarn side is more prone to problems such as thread breakage, filament cracking, filament sagging, and curling during knitting, and as a result,
This may result in the knitting machine stopping or producing many knitted defective products.

Here, ficimen 1 ~ cracking is a phenomenon in which all the filaments of the yarn do not enter the knitting needles, and some of the filaments float up and are not knitted, and these lifted filaments get entangled with the regular knitting section and cause the knitting machine to stop. provoke. In addition, since it is not knitted with all the regular filaments, the knitted part becomes thin and transparent, which makes it a defective product and cannot be used as a product.

On the other hand, when the flat yarn according to claim 1 of the present invention is used, the occurrence of troubles such as yarn breakage and filament cracking described above can be significantly reduced. this is,
The amount of oil adhering to nylon flat yarn was reduced to the conventional level (0).
, 8 to 1.2% by weight), even if it is a flat yarn with few filaments, its convergence can be improved, and the stress concentration in each filament can be reduced and alleviated. This is thought to be due to the

In this way, a large amount of oil adhesion is effective in preventing yarn breakage during cross-knitting and improving the quality of knitted fabric products, but in particular,
It becomes significantly better at 1.6% by weight or more. However, if the amount is too large, the yarn becomes sticky and the unwinding performance deteriorates, and the knitting performance and quality of the knitted fabric deteriorate due to the formation of oil pools on the guides and the adhesion of dust to them. Because it invites
It is necessary that the content be at most 2.4% by weight.

Such a nylon flat yarn with an oil coating amount of 1.6 to 2.4% by weight can be obtained by simply increasing the amount of spinning oil coating, but it can be obtained by simply increasing the coating amount of the spinning oil, but it is difficult to operate during spinning and drawing. From the viewpoint of properties, the amount of spinning oil applied is 1.
The yarn spinning method according to claim 3, wherein the amount of oil attached is kept within the above range by suppressing the amount to 2% by weight or less and adding oil after stretching.

The amount of pre-stretching oil applied during spinning is 1.2% by weight.
If it exceeds this value, the occurrence of yarn breakage in the drawing step 14 will increase, resulting in extremely unstable yarn reeling properties, and the shape of the winding package will also deteriorate when the yarn is wound as an undrawn yarn. In addition, the oil agent scatters more frequently in the thread passing portion after the oil applying portion, resulting in the occurrence of oil stains and oil scum on the device in these yarn passing portions, as well as oil stains on the winding package.

In this way, it is better to use less oil before drawing, but in order to obtain the flat yarn of claim 1, the amount of oil applied to the yarn obtained by crystal orientation must be at a level of 2.4% by weight or more. Therefore, it is necessary to add oil to the remaining lubricant after stretching or crystal orientation.

Further, the package formed by winding the nylon flat yarn into a pirn shape has a ridge angle of 1 to 5 degrees, and the pirn package according to claim 2 further improves the knitting performance during inter-knitting and the uniformity of the product knitted fabric. It is effective for

On the other hand, if the edge angle is about 0 degrees (horizontal winding), yarn breakage during cross-knitting and thread throwing from the pirn tend to occur more often, so the package edge angle should be set to 1 degree or more. good. However, if the ridge angle becomes too large (more than 5 degrees), threads tend to fall off at the tapered part of the package, and fluctuations in unwinding tension increase, leading to more thread breakage during alternate knitting. It is inappropriate to do so.

Furthermore, the larger the package winding ω (pern diameter),
Since the unwinding property is good, in order to further suppress the occurrence of troubles during alternate knitting, it is preferable that the pirn diameter is 110+11 mφ or more.

[Example] Example 1 A 15-denier, 3-filament drawn nylon 6 yarn (flat yarn) was spun by the usual method of melt-spinning nylon 6, winding the undrawn yarn, and then stretching it, and using a ring twisting yarn winding machine. Tilt the ring with and wind it at a ridge angle of 3 degrees.
The package had a pirn diameter of approximately 130 mmφ.

At this time, 0.8% by weight of a water emulsion type oil agent mainly consisting of low viscosity mineral oil was applied to the fibers as a spinning oil agent used in the melt spinning process, and an ester-based smoothing agent was added to the fibers after stretching and before winding. A straight lubricant containing 85% of a smoothing agent mainly composed of a lubricating agent was added.

In addition, for the coated elastic yarn, a 20 denier, 3 filament spandex fiber yarn and a 10 denier, 7 filament 6-filament nylon yarn were pre-twisted in the Z direction 3.
000 t/m, ply twist S direction 2600 t/m, and double covering yarn was used in a conventional manner.

The obtained nylon 6 flat yarn and the above-mentioned covered elastic yarn were cross-knitted using 4 yarn feeding, 400 needles, and 4 cylinder diameters.
Using an inch stocking knitting machine, the knitting machine rotation speed was 90 O.
It was performed at rpm.

The number of yarn breakages and hoop handling in this stocking knitting process and the quality (number of holes, stitch uniformity) of the obtained stocking fabrics were evaluated, and the results are shown in Table 1.

In Table 1, the frequency of occurrence of thread breakage, occurrence of ring toss, and occurrence of holes in the product during alternate knitting is expressed by the number of occurrences in 200 stockings. Attach 30 fabric samples to an inspection board and count the number of filament cracks (unknitted yarn of single yarn) in the stitch loops, and determine the occurrence rate as 0/3.
The cases of 0.1/30.2 to 4/30.5 or more/30 were respectively indicated as A: good, B: slightly poor, C: poor, and D: extremely poor.

As can be seen from the results in Table 1, in the cases of Nos. 4 to 6 according to the present invention (claim 1), yarn breakage during alternating knitting was greatly reduced. In general, it was possible to prevent holes in the product knitted fabric due to stitch breakage and stitch skipping, and furthermore, stitch defects due to filament cracking were also greatly improved.

On the other hand, in the case of Nb, 1 to 3, in which the amount of oil attached was too small, there were many yarn breakages during cross-knitting, and the quality of the knitted fabric product was poor. Furthermore, if the amount of oil adhesion was too large (NO, 7>), the incidence of yarn breakage and the occurrence of holes in the product increased, resulting in poor product quality.

Example 2 A 12-denier, 3-filament drawn nylon 66 yarn (flat yarn) was melt-spun into an undrawn yarn by the usual method of stretching in one direction, and the rings were tilted using a ring twisting winder. This was rolled up at a ridge angle of about 2 degrees to form a package with a burn diameter of 125 mm.

At this time, a water emulsion type oil mainly containing an ester leveling agent was used as a spinning oil in the melt spinning process, and the same straight oil as in Example 1 was added after stretching and before winding. .

The quality of the undrawn yarn winding package during spinning was evaluated by visual inspection, and the occurrence of yarn breakage during drawing was expressed as the number of yarn breakage occurrences per 50 ko of drawn yarn, and is shown in Table 2.

The obtained nylon 66 flat yarn was used under the same covered elastic yarn and cross-knitting conditions as in Example 1 (however, the knitting machine rotation speed was 1l10).
A knitted stocking fabric was produced by alternating knitting with 0rp).

The number of thread breaks during the stocking knitting process and the quality of the stocking fabric obtained were evaluated in the same manner as in Example 1, and the results are shown in Table 2.

As can be seen from the results in Table 2, in the cases of Nos. 4 to 16 according to the present invention (Claim 2), the spinning properties, the knitting properties during cross-knitting, and the quality of the product knitted fabrics were all good. .

On the other hand, No. 2, where there was no additional oil and the amount of oil attached was too small.
In cases No. 11 to 13, there were many yarn breakages during cross-knitting, and the quality of the knitted fabric products was poor. In addition, in cases No. 17 to 19 where the amount of oil supplied during spinning was too large, the amount of oil applied to the package satisfied the present invention and the knitting properties and product quality were good, but the amount of oil supplied during spinning was Since the amount was too large, the spinning properties were extremely unstable and the undrawn yarn had a poor winding package shape.

Furthermore, thread breakage occurred frequently during stretching, resulting in poor productivity.

Example 3 No. 1 of Example 1 except that the ring inclination angle during winding was changed.
Nylon 6-perm packages with various edge angles were obtained by spinning under the same conditions as in Example 1, and knitted in the same manner as in Example 1 to produce knitted stocking fabrics.

The number of yarn breaks, the number of ring bales, and the quality of the obtained stocking fabric in the stocking knitting process were evaluated in the same manner as in Example 1, and the results are shown in Table 3.

As is clear from the results in Table 3, the package edge angle is
The cases of NO, 22, 5, and 23, which were set to ~5 degrees, were most effective in preventing yarn breakage during cross-knitting and improving the quality of knitted fabric products.

On the other hand, No. where the package edge angle was too small.

In case No. 21, there were many occurrences of yarn breakage and loop handling during cross-knitting, and uneven portions occurred in the product knitted fabric.

In addition, in the case of No. 24 where the package edge angle was too large, the unwinding tension fluctuated greatly when unwinding from the package, yarn breakage occurred frequently during cross-knitting, and the uniformity of the product knitted fabric decreased. did.

[Effects of the Invention] According to claim 1 of the present invention, troubles such as yarn breakage and filament cracking during alternating knitting can be greatly suppressed,
It is possible to greatly improve the knitting properties and the surface defects and appearance uniformity of the resulting cross-knitted product, and to increase the product yield. Furthermore, as the knitting properties are improved, the knitting speed at which knitting can be done without trouble increases, and high-speed knitting becomes industrially possible.

Further, according to claim 2 of the present invention, the circular handling during alternating knitting can further suppress the occurrence of yarn breakage, thereby further improving knitting performance and loading quality.

Furthermore, according to claim 3 of the present invention, the nylon flat yarn of claim 1 can be produced with good spinability.

The present invention is generally applicable to the production of stretch knitted fabric products by inter-knitting covered elastic yarns and nylon flat yarns, but is particularly effective for producing stocking products by inter-knitting. .

Claims (3)

[Claims] (1) The oil agent, which is mainly composed of a smoothing agent, is applied to the fibers from 1.6 to
A nylon flat yarn for inter-knitted fabrics, characterized in that it has an adhesion of 2.4% by weight and the number of filaments is 2 to 7. (2) The nylon flat yarn of claim 1 has an edge angle of 1 to 5.
A pern package of nylon flat yarn for inter-knitted fabrics, which is characterized by being wound into a pern shape. (3) Adding 1.2% by weight or less of an oil agent mainly composed of a smoothing agent to an undrawn nylon yarn having 2 to 7 filaments after cooling the spinning, and then crystallizing it by drawing and/or high-speed pulling, After that, an oil agent mainly composed of a smoothing agent is further applied to produce a nylon flat yarn for an inter-knitted fabric having an oil adhesion amount of 1.6 to 2.4% by weight. Method of manufacturing nylon flat yarn.