T-506 SEN-I GAKKAISHI (報文) (86)

Technical Section(Received July 31, 1980)

CONE TEXTURIZING OF CONTINUOUS FILAMENT YARN*1

By Meiji Anahara, Takayoshi Fujita *Yukio Kawasaki *3 and Shuh Sengoku

(Katata Research Center, Toyobo Co., Ltd., 1300-1, Honkatata-cho, Otsu-shi, Shiga-ken.)

It is possible to insert a real twist into continuous filament yarn through a false twist mechanism by godet spinning. The secret of this novel method is that not the twist inserted in monofilaments, but only the twist added to the filament bundle is recognized as a real twist. As the defects of this method, large accumulating ratio or overfeed and large loops projecting from the periphery of the

yarn were pointed out. In this paper elimination of these defects were attempted by applying two methods of opening a multifilament yarn into monofilaments. Many factors which affected the operating efficiency and yarn properties were described. The yarn thus obtained was found to have much less snarling tendency compared to the conventionally twisted yarn. Properties of the fabric woven from the obtained yarn were similar to those from the spun yarn rather than to those from t he texturized yarn.

1. INTRODUCTION

Spinning speed of staple fibers has greatly been enhanced by the open-end spinning system com

pared to the conventional ring-traveller system. The open-end system is a novel twisting method which operates without rotating the yarn package

by breaking the fiber bundle fed. Therefore it is not easily applicable for twisting a continuous filament yarn. But new method called "cone spinning" or "godet spinning" were introduced by Cannon1) et al. in 1971, as an extension of the open-end spinning of continuous filament yarn. These methods have certain advantages for insert

ing a real twist into the filament yarn through a false-twist set-up, and for obtaining a new yarn having configuration looks and feels like ordinary staple fiber yarn consisting of a twisted bundle of loops. But at the same time it was pointed out that these methods had two drawbacks; one was a

necessity of about hundredfold over-feed on the

process and the other was inferior yarn appearance with too many hairy loops projecting from the

yarn periphery.These drawbacks may come from the winding

of the fed filament yarn traversing on the surface

of a large godet roller as a single filament bundle,

which may be resolved by employing some suitable

yarn feeding method for the opening of a multifilament yarn into monofilaments and the winding

on the surface of a small diameter spindle. In this

paper, two kinds of opening apparatus are applied

to decrease the overfeed in the godet spinning

method, and the yarn and fabric properties ob

tained are described.

2. PRINCIPLE OF TWIST FORMATION

A multifilament yarn fed through an opening

apparatus is separated and opened into mono

filaments and wound on to the surface of a conical

shaped rotating spindle to form a filament sleeve

on it. The separated monofilaments traverse spon

taneously to the rotating spindle axis because of a

difference of tension among each filament having

same length originally but having been wound at

different diameter. This phenomenon resembles

filament behaviour well known as migration in the

twisting process.2) Each monofilament from a

multifilament yarn can be assumed to behave

similarly, so it will be sufficient to consider about

a monofilament. Fig. la illustrates that a mono

filament wound on a conical spindle rotating in

*1 Application of False -twisting Method Part 1*2 Manmade Fiber Processing Technical Center

, Toyobo Co., Ltd., 10-24, Toyo-cho, Tsuruga-shi,

Fukui-ken.*3 Rosewood Fabrics

, Inc., 1450 Broadway, New York, U.S.A.

(87) Vol. 36, No. 11 0980) T-507

Fig. 1. Illustration of twist formation.

clock-wise direction, when it is seen from the left-hand, with traversing from right to left, will be twisted in z direction when it is withdrawn to the right direction of the spindle without rotation.

On the contrary, a filament wound with left to right traverse direction on the spindle will be twisted in s direction when it is withdrawn as

shown in Fig. lb. The twist number added to each part of the monofilament is given by equation

(1) and (2), respectively.

(1)

(2)

where nz and ns are twist numbers per unit length

(t/m), a is rotating velocity of spindle (r.p.m.), vo is the feeding velocity of a multifilament yarn

(m/min) and d is the substantial mean diameter of the spindle (m).

When these alternately twisted sections of filament are withdrawn together at velocity vi with spindle rotation and continuous winding of newly

fed filament, the length of each section per unit time will be changed to vo+vi (z twist part) and vo-v1 (s twist part) respectively by the transfer of a section of s twist part into z twist part as shown in Fig. lc. The spindle rotation adds s twist to the

withdrawn filament bundle of these parts to make

a yarn of many folded loops.

Twist number added to each monofilament per

unit time

(3)

Plied twist number added to filament bundle

per unit time

(4)

The twist added to monofilaments is not recognized. Only plied twist is recognized in the obtained yarn, so that this twisting method will be considered as if the real twist can be gained through a false-twist mechanism. But it is easily comprehensible from the principle of the twist formation that the total twist applied to the fed multifilament yarn should be cancelled as shown by the equivalents in equations (3) and (4). Relating to this twisting behaviour, an interesting feature about torsional property is found. Fig. 22 shows that the yarn obtained by this method has far lower snarling tendency compared to the conven

tional plied yarn.

3. EXPERIMENTAL

3.1 Experimental methodA multifilament yarn was fed from a yarn

T-508 SEN-I GAKKAISHI (報文) (88)

package to a rotating hollow spindle by a pair of feed rollers through an opening apparatus as shown

in Fig. 2a. The monofilaments were wound around

the surface of the spindle as a thin layer of fila

ments or filament sleeve. The filament sleeve was

slipped toward the tip of the spindle, everted into

the hollow shaft of the spindle, withdrawn through

the hollow shaft by a pair of delivery rollers and

taken up on the yarn package. Another yarn was

supplied to the spindle tip as a core yarn according

to the experimental conditions, wrapped by the

filament sleeve and taken up together with it. In

another case the sleeve was also withdrawn to the

tip of the spindle as shown in Fig. 2b. In this case

the core yarn was supplied through the hollow shaft of the spindle. The feed rollers were not necessarily used.

3.2 Yarn opening apparatus3.2.1 Electrical apparatus3)

This apparatus is constructed from high voltage charged tube electrode 1 and earthed skirt-like electrode 2 as shown in Fig. 3. A multifilament

yarn while passing through a tensioner, electrode 1 and 2, is separated and opened into monofilaments in the electrode 2 by repulsion of the electric charge on filament surface given at the electrode 1

and by the action of an intensive electric field between the two electrodes. A photograph of

Fig. 2. Schematic view of the experimental set-up.

* Accumulating ratio was calculated by dividing the surface velocity of feed roller I

by that of the delivery roller.

Fig. 3. Electric apparatus for opening

multifilament yarn.Fig. 4. A photograph of opened filaments.

(89) Vol.36, No. 11 0980) T-509

opened monofilaments is shown in Fig. 4.3.2.2 Pneumatic apparatus

This unit comprises an ejector and a plate faced closely to the exit of the ejector as shown in Fig. 5. A multifilament yarn led by a compressed air stream to the curved plate through an ejecting tube is opened by the spreading air flow along the

sliding plate. A side view of the ejector used is shown in Fig. 6.3.3 Spindle

A number of spindle periphery shapes made of bakelite or steel with hard chrome plating were tested. Typical ones were the truncated conical shaped hollow spindle and the double conical shape hollow spindle shown in Fig. 7. The peripheral dimensions of the spindles are given in Table 1.3.4 Multifilament yarn

Regular Polyethylene terephthalate (PET) multifilament yarns for example total 20 denier constructed from 12 monofilaments (described as 20D-12F hereafter), 30D-18F, 50D-24F were mainly used.

Fig. 5. Pneumatic apparatus for opening a multifilament yarn.

Fig. 6. A side view of ejector. Fig. 7. Side views of typical spindle.

Table 1 Dimension of spindle.

T一510 SEN-I GAKKAISHI(報 文) (90)

4. RESULTS AND DISCUSSION

4.1 Electrical opening method4.1.1 Factors affecting the opening efficiency

The electrical opening apparatus was located at right angles to the axis of the rubber roller, of which the diameter was 50mm, so as to make the distance of 30mm from the roller surface to the edge of earthed electrode 2. Various kinds of PET filament yarns were fed to the roller surface

through the electrical apparatus with a speed ranging 80 to 800m/min under various conditions.

The opening efficiency of the multifilament yarn was judged from the observed spread of the filament sleeve accumulated on the roller and from the uniformity of the distribution of monofila

ments in the sleeve. The opening efficiency was lowered by lowering the voltage charged to

electrode 1 and by increasing pre-tension, feeding velocity, yarn denier or filament number of the feed yarn. However it was judged that the opening could be kept stable and satisfactory by selecting suitable conditions, viz., less than 4.5 kilo-volt

charged on the electrode, 700m/min in feeding velocity, 0.05 g/den for the pre-tension, and 75

denier or 36 filaments in feeding yarn under standard temperature and relative humidity.4.1.2 Inclination angle of the spindle

The effect of the inclination angle of the spindle was tested by settling 8 kinds of double conical

spindles in turn, which were different in the inclination angle from 0 to 20 degree with keeping

the diameter at the tip 14.5mm, in the experimental arrangement shown in Fig. 2. PET 20D-12F

was fed at feeding velocity 380m/min and overfeed or accumulating ratio (abbreviated as A. R. hereafter) was 15 times, which was defined as the ratio of feeding yarn velocity to withdrawing velocity. The operating condition and some proper

ties of the yarn obtained are summarized in Table 2. Small inclination angle 6 as 1 degree prevented the smooth slip on the spindle surface and on the other hand, large angle more than 5 degree worked against the stable winding of opened filaments. Therefore, in both cases yarn breaking occurred frequently and yarn properties were inferior in

Table 2 Effect of inclination angle on the yarn properties.

Operating conditions:Vo=380m/min. Double conical shape spindle PET 20D-12F

v1=25m/min. D1=14.5mm Voltage charged=4.5KV

A.R.=15times D4=8.5mm=8700 r.p.m.

*It was impossible to obtain the yarn when =0,15 and 20 degree.** Yarn evenness was measured by Uster's Yarn Evenness Tester in normal scale throughout

this study.

(91) Vol.36, No. 11 0980) T-511

breaking strength and U% compared to those obtained by using the spindle having an inclination angle between 2 and 3.5 degree. So rather small angles as such were thought to be preferable for both of the operation and yarn property. Table 2 shows that the withdrawing direction gives no clear effect on the operating efficiency but the breaking strength of the yarn obtained by back-ward withdrawal with eversion was a little superior to that of the yarn obtained by forward with-drawal. It was observed that large loops projecting from the former yarn periphery were much less than those from the latter. So it was inferred that by eversion outer loops formed on the filament sleeve were wrapped tightly in the sleeve and that the former yarn had more effective filament loops against stretching.

Filament loops projecting from the yarn periphery are not only undesirable for the yarn strength and appearance but also have a serious influence upon smooth taking-off from the

package, because the loops projecting from longitudinally different positions on the yarn entangle each other just as bel-cro effect. To eliminate this undesirable phenomenon, backward withdrawal was suitable as mentioned above. Some other means were also found effective. One of them was a balloon controller provided at a small distance of about 2mm from the tip of the spindle and another was the increase in the twist number

Fig. 8. A side view of balloon controller.

of the obtained yarn. The balloon controller contacts with loops projecting from the slipping sleeve near the tip of the spindle to press them into the sleeve with the rotation of the spindle. The shape of the balloon controller is not limited but one of the suitable shapes for double conical spindle is shown in Fig. 8. Moreover the yarn evenness and breaking strength were also much improved by the action of the balloon controller as shown in the bottom columns of Table 2. But with the insertion of the balloon controller the

preferable inclination angle of the spindle remained unchanged, viz., 2 to 3.5 degree. Results being not shown in Table 2, the controller was also effective for the yarn properties obtained under forward withdrawal.4.1.3 Diameter of the spindle

Three kinds of double conical spindle, of which diameters were 14.5, 8.6 and 5.0, were examined for the backward withdrawal and other operating

Table 3 Effect of spindle diameter on the yarn properties.

Operating conditions: Backward withdrawal Sheath Y.; PET 30D-12F

Double conical shape spindle Core Y.; PET 100D-24F

8=2•‹

ct=60•‹

8=105•‹

T-512 SEN-I GAKKAISHI(報 文) (92)

conditions given in the footnote of Table 3 with

balloon controller or core yarn. Instead of the

balloon controller a core yarn supplied to the tip

of the spindle was effectively to prevent the

projection of loops by entangling with them before

projecting. Supply angles of the core yarn, a and

,0 were measured as an angle between supply

direction of core yarn and withdrawal direction of

product core yarn, and an angle between the

direction parallel to the opened filament sheet and

the supply direction of core yarn around. the

spindle shaft by counter clockwise direction as

shown in Fig. 9. According to the results given in

Table 3, it was clear that a spindle having a small

diameter reduces A.R. although such a spindle

tends to decrease the yarn evenness. When a core

yarn was supplied at angles a=60•‹, 8=105•‹, satis-

factory operating efficiency and yarn evenness

were ensured even with a small diameter spindle

with extremely small A.R. As the substantial

spindle diameter is expressed by d=(vo/v1)/

?? (Ns/vl) from equations (3) and (4), it is essential to use a small diameter spindle to decrease A.R. and to provide high twist to the yarn, because such a spindle can be easily driven in high revolution.4.1.4 Effect of core yarn

Under backward withdrawal with eversion, a core yarn reduced the irregularity of the product

core yarn but this effect was dependent upon its supply angles, a and d as shown in Fig. 11 and 12, respectively. In the product core yarn, multifilament yarn wrapped naturally around the original core yarn as sheath yarn. The results shown in Fig. 11 indicate that the smaller the angle a, the higher the yarn evenness and this effect is a little reduced when the spindle diameter or A.R. becomes small. These trends may come from the increased balloon controlling effect resulting from

the hard contact and effective press of projecting loops by a core yarn supplied in a small angle. As

the projecting loops become taller with the increase of the diameter of spindle, the core yarn will work effectively depending on the spindle diameter. But there is a lower limitation for a, because the

Fig. 9. Explanation of angle a and /3.

Fig. 10. Explanation of the distance x.

Fig. 11. Relation between the yarn evenness and

the supply angle of core yarn.

0=2•‹, 0=105•‹

Sheath Y.; PET 20D-12F

Withdrawal V.; 45m/min.

(93) Vol.36, No. 11 0980) T-513

Fig. 12. Relation between the yarn evenness and the supply angle of core yarn.

Fig.13. The yarn evenness and accumulating

ratio plotted against the distance for

m winding center line to spind1e tip.

θ=2°,x=9mm

Sheath Y.;PET 20D-12F

Withdrawal V.;45m/min

D1=2mmφ,θ=2°,ω=22.5xlO3 r.p.m.

SheathY.; PET20-12F

CoreY.; PET100-24F

WithdrawalV.; 45m/min.

core yarn is apt to be entangled with the rotating

sleeve to be broken, or apt to wrap on the spindle surface when the angle is excessively small. So the smallest limit of the angle seemed to be 30 degree. With regard to the supplying a core yarn, the

position of opened multifilament yarn on the spindle surface was found to have a noticeable effect upon the yarn evenness. The position was conveniently expressed by the distance x between the tip end of the spindle and the winding centerline of the opened filament bundle (cf. Fig. 10). In the case of the distance x=9mm, the yarn evenness was much improved comparing to the other cases, in which all of the opened filaments

were wound on the spindle. When the distance was less than half of the spread of the opened filament bundle, only fraction of the whole monofilaments could be wound on the spindle surface and the remainder had to be supplied to the location in front of the spindle tip. The filaments, which were led to the hollow shaft directly, did not meet irregular slip on the surface of the spindle and were inferred to contribute to improve the yarn evenness. It was very difficult to judge the ratio of unwound monofilaments to those wound on the spindle, but in the case of x=9mm it seemed to be

about 20% considering the spread of the filament bundle over ca. 25 mm. In this case also, supply

angle ct had a similar effect on the yarn evenness

as shown in Fig. 11. Being clearly suggested by the

explanation above, the yarn evenness was im

proved by decreasing the distance x as shown in Fig. 13. But in this figure it had to be considered

that the ratio of sheath yarn decreased in the

product core yarn with the increase in the distance x.

Fig. 12 shows that the angle 8 between 90 and

150 degree suitable irrespective of the other operating conditions. But it seemed necessary to avoid small angle near 0 degree for angle d, because the core yarn interfered in the opened filaments before they reached the spindle surface.As a whole, angle 8 had less effect on the yarn evenness than angle d.4.1.5 Accumulating ratio

Some yarn properties are shown against A.R. in Fig. 14. In this figure the twist number is also

given to take account of the interaction with A.R. Yarn evenness showed a maximum at certain A.R. It was thought that the decreasing ratio of a core

yarn in the obtained yarn in the small A.R. range and the increased twist number in the large A.R. range gave such maximum. With constant twist number as shown by dotted line in the figure, yarn evenness was kept almost constant against the

change of A.R. When the core yarn used was

T-514 SEN一1 GAKKAISHI (報文) (94)

Fig.14. Snarling tendency, breaking strength and

yarn evenness as functions of accumu-

1ating ratio and twist number.

Ｄ1=2mmφ,θ=2°,α=60°,β=105°

x=9mm,A.R.=4.3

SheathY.; PET20D-12F

CoreY.; ○PET 25D-6F

●PET 100D-24F

thick, the product core yarn had naturally low U%. Yarn breaking strength seemed to change mainly depending upon the twist inserted in the

yarn, because it increased to a certain level with the increase of twist number on account of the

coherency of filament loops and decreased with excessive twist number. This interpretation was

supported by results that the yarn, of which twist number was kept constant, showed no decline of the breaking strength in the high A.R. range as shown by a dotted line in the figure. Two core

yarns used gave a difference in the breaking strength.

Torsional property of the obtained yarn was estimated by the snarling tendency which was measured by hanging a small weight (5mg/den) at

the bottom of a loop made from the yarn, allowing it to rotate freely and counting the twist number added in the loop after ensuring the stability. The snarling tendency increased monotonically in the

case of thick core yarn but it tended to saturate with increasing twist in the case of thin core yarn. As the core yarn had no twist in the obtained yarn, the difference of the snarling tendency found for the two core yarns was thought to stem from the torsional property of the core yarn included.4.1.6 Feeding velocity of multifilament yarn

Yarn evenness changed depending upon the operating velocity with keeping A.R. constant as shown in Fig. 15. The increased U% of the obtained yarn under increasing operating velocity may be correlated with the high revolution of the spindle and the opening effect of multifilament

yarn. High revolution such as 75,000 r.p.m. of the spindle made a rapid air current around it to disturb procession of the opened filaments and made filament loops easily project from the sleeve by an increased centrifugal force. The opening effect of multifilament yarn seemed to be decreased chiefly by the increased feeding yarn tension at any speed higher than 500m/min especially for 30D yarn comparing to 20D one, Therefore it seemed to be preferable to adopt a feed velocity lower than 600 m/min for the present electrical opening method. Under the operating conditions adopted above, it was recognized that A.R. realized in the present method with opening multifilament yarn ranged from 5 to 15. This was extremely small compared

Fig.15. Relation between yam evenness and

o perating velocity.

D1=2mmφ, θ=2°, A.R.=4

α=60°, β=105°, x=9mm

Sheath y.; ○PET 30DL 18F

●PET 20D-12F

Core y.; PET 100D-24F

(95) Vol.36, No. 11 0980) T-515

to the hundredfold values in the original method.Such low A.R. with satisfactory operating efficiency except the feeding velocity of multifilament

yarn was realized by the high entanglement of filament network.

4.2 Pneumatic methodIn the pneumatic method to open a multifila

ment yarn into monofilaments, there is no appreciable difference in processing conditions from the

electric method mentioned above, except that the multifilament yarn is led to the spindle surface

positively by compressed air. Therefore the effect of opening filament yarn by the pneumatic method will be focussed in this section.4.2.1 Ejector

The ejector used in the experiments was a conventional one but was specially designed to make various parts of them changeable. The side view of the ejector is shown in Fig. 6. The ejector has 2 important functions, to suck and separate a multifilament yarn effectively under low air con

sumption. Air flow in the ejector clearly changed according to the air pressure fed as shown in Fig. 16, and agreed well with the flow calculated by the theoretical pneumatic relationship. The suctorial

power of the ejector was estimated by a force

Fig. 16. Relation between air flow and air

pressure.

Fig. 17. Opening effect and yarn evenness as

functions of air flow.

She. Y.: PET 50D-24F

Cor. Y.; PET 100D-24Fφ1 φ2

○0.8 1.2

●1.0 1.2

necessary to fix a yarn, PET 150D-30F, of which end reached to the exit of the ejector through a conduit, when compressed air was supplied. The opening effect was judged by observing accumulated state of monofilaments emitted from the ejector and accumulated on a mesh settled at the end of the sliding plate instead of the spindle. Both the auctorial power and separating effect of the ejector increased with increasing air flow or air pressure as shown in Fig. 17. But the regularity of the obtained yarn was decreased on the contra

ry. Probably an excessive air flow disturbed smooth processing, or winding on the rotating spindle, of the opened monofilament bundle in spite of the sufficient separation of the bundle. However the two functions of the ejector were effected satisfactorily by a wise choice of the dimensions, for example, 01=1.0 mm, 02=1.2 mm. In a pneumatic opening system, it is essential to use feed rollers for the multifilament yarn to prevent excess feeding.4.2.2 Sliding plate

A sliding plate situated close to the exit of the ejector was constructed with a slightly convex part and a flat plate as shown in Fig. 5. Being led to the exit of the ejector by air flow, a multifilament

T-516 SEN-I GAKKAISHI(報 文) (96)

Fig. 18. Air velocity chart around sliding plate.

yarn runs against the convex part and slides on the sliding plate in separated state to a rotating spindle located at the end of the plate. In this pneumatic method, spreading of air flow to its tangential direction seemed to play a very important role in opening a multifilament yarn as shown in Fig. 18. To control this expanding air current, it was found effective to provide a convex part facing to the exit and a low fence surrounding the collision

point on the convex part as shown in Fig. 5.4.2.3 Operating conditions

In the pneumatic method it was easily possible to feed PET yarn with a velocity higher than 1,000m/min with satisfactory opening effect. With the increase in feeding velocity, the yarn evenness was rather decreased not only by the high revolution of the spindle with the increased air current around it and consequently with the increased centrifugal force to throw out filament loops, but by the heavy air flow from the ejector itself. It was necessary to add more twist than spun yarns to collect filament loops in the yarn, to reduce the deformation by loading or to improve yarn evenness as shown in Fig. 19, so withdrawing velocity could not be much increased over 200m/min.4.3 Yam property

A photograph of one of the yarns obtained by this method is shown in Fig. 20. The highly twisted structure with many projecting loops can be clearly observed. There are three important features in the properties of the yarn, viz., real twist, snarling tendency and entangling effect. It was very difficult to measure the twist added

Fig. 19. Relation between yarn properties and twist number.

* Fur-index was measured by Fur-index Meter

made by Shikishima Spinning Co., Ltd.

Spindle R. (r.p.m.) She. Y.: PET 50D-24FO 24x104 Core Y.; PET 100D-24F

O 20 A.R.; 7

v 16 •œ 12

Fig. 20. A photograph of the yarn obtained by

this method.

Operating conditions:Backward withdrawal A.R.=7times

Sheath Y.; PET 50D-24F vo=1120m/min.Core Y.; PET 100D-36F vl=160m/min.D1=2mm,θ=2° Tw.=500 t.p.m.

ω=8xlO4 r.p.m, Air P.=3kg/cm2

α=60°,β=105°

because the yarn contained many entangled filament loops which made some trouble in detwisting to judge the 0 twist level. So the measured twist scattered somewhat around the calculated values from (a /v1 ), but the agreement found in Fig. 21 is fair.

(97) Vol. 36, No. 11 (1980) T-517

Fig. 21. Comparison between measured and calculated twist numbers.

Fig. 22. Comparison of snarling tendency be

tween conventionally twisted yarn and the obtained yarn.

The snarling tendency, some of it was mentioned

already, is shown comparatively to that of con

ventionally twisted yarn in Fig. 22. The yarn

obtained by this method included a core yarn

without twist, so their direct comparison might be

meaningless. But their difference was quite large

to judge that the snarling tendency of this yarn was far lower than that of the conventional yarn.This interesting feature was clearly derived from its twist formation principle mentioned already.

By the entangling effect between filament loops

projecting from longitudinally different positions of the yarn, high tension variation was inevitable in taking off the yarn from the yarn package. There were many ways to eliminate this phenomenon such as lubrication, heat treatment to shrink

projecting loops or adopting a multifilament yarn constructed from fine monofilament etc., but none of them were sufficiently effective. The similar troublesome phenomenon is found in the case of treating a looped bulky yarn.4.4 Fabric property

Some properties of the fabrics woven by the spun loom, dyed and finished by conventional processes for texturized woven fabrics are summarized in Table 4 in comparison with those of texturized yarn and spun yarn fabrics. Yarn

properties are also included in the table. Sizing was not necessary for the present yarn to use as warp

yarn, because it was sufficiently twisted against frictional treatment on the loom. According to Table 4, the fabric property woven from the yarn of this method is rather similar to that of the spun yarn than that of texturized yarn. But actual hand of the fabric feels a little harsh comparing to that of spun yarn.4.5 Application

Being judged from both the operating velocity and the dimension of the devices, the present method of opening a multifilament yarn seems to be not suitable to the spinning process but suitable rather to drawing or texturizing process. Therefore the method should be called `cone texturizing'

Table 4 Comparison of yarn and fabric properties for 3 kinds of yarns.

* Experimentally obtained yarn: Sheath Y .; PET 50D-24F, Core Y.; PET 100D-36F, A.R.=7** Falst-twist texturized PET 150D-48F

*** PET 1.5d-38mm, Ne 45**** Plain fabric , Experimental yarn was commonly used as weft.

T-518 SEN-I GAKKAISHI (報文) (98)

rather than 'godet spinning'.

5. CONCLUSION

1) Large accumulating ratio, one of the defects of the godet spinning method, was highly reduced by applying two yarn feeding methods which could separate and open a multifilament yarn into monofilaments.

2) Either an electrical or pneumatic apparatus for opening multifilaments was applicable to this method, but the latter could treat a multifilament

yarn at higher velocity than the former.3) A spindle having small diameter was prefer

able to decrease A.R. but such a spindle had an inferior point to decrease the evenness of the obtained yarn.

4) To improve yarn evenness, it was effective to insert a balloon controller near the tip of the spindle, supply a core yarn to the tip of the spindle so as to contact with projecting loops or to supply a part of the opened filaments to the location in front of the tip.

5) Snarling tendency of the yarn obtained by this method was much less than that of the conventionally twisted yarn.

6) For this type of yarn with many loops, high

yarn tension variation is inevitable in taking off from the package, which remains to be resolved.

7) Properties of fabrics woven from the yarn were similar to that of the spun yarn rather than that of texturized yarn.

6. ACKNOWLEDGEMENT

The authors wish to express their sincerest thanks to Mr. M. Tahara, director of Toyobo Co., Ltd., for his encouragement of this study and

permission for the publication. Respects and thanks are paid to Professor J. Shimizu, Faculty of Engineering, Tokyo Inst. of Technology, for his valuable suggestions and comments.

REFERENCES

1) C. G. Cannon, B. L. Davis, A. Selwood and R. A. Williams, J. Text. Inst., 62, 622 (1971)

2) J. W. S. Hearle, P. Grosberg and S. Backer, Structural Mechanics of Fibers, Yarns and

Fabrics, Vol. 1, p. 101, Wiley Interscience

(1969)3) S. Uchiyama, Y. Miyagawa, M. Kobayashi,

J. Text. Machine Soc. Japan, 25, T189 (1972)

仮 撚 に よ る フ ィ ラ メ ン ト糸 の 実 撚 賦 与

東洋紡績㈱総合研究所 穴原明司,藤 田隆善,斜 崎幸夫,仙 石 秀

仮撚 法 によ って糸 に実 撚を残留 させ ることはで きない

が,ゴ デ ッ トス ピニ ング法 は特 殊 なメカニ ズムによ り,

定 常的 な実撚を与 え ることがで きる。この方法 は供 給 フ

ィラメ ン ト糸を ロー ラ上 にま きつ け,軸 方 向 に供給 速度

の1/100程 度で ひき出す もので,速 度比(堆 積 比)の 大

きい点,糸 表面 に多数 のル ープが突 出す る点 が欠点で あ

った。本報告 は,こ の方法 の原理を考察 し,フ ィラメ ン

ト開繊 法に より欠点 を大 巾に解消 し得 る見通 しを得た の

で,操 作性,糸 質に関連する要因として,開 繊方法,回

転体の形状,フ ィラメン トのまきつけ位置,芯 糸の供給

方法などの検討結果について述べ る。本方法により,見

かけ上実撚が糸に残留す るが,本 質的には仮撚であるた

あ,得 られた糸の旋回性は通常の加撚糸に比べてはるか

に低い。糸の形態は繊維束の周囲を多数のループが,ら

線状に被覆 しており,織 物物性は加工糸よ り紡績糸に近

い値を示した。