DE1660438A1 - Method and device for crimping mixed fiber yarns - Google Patents

Description

K & NEGAFÜCHI BOSEKI KABUSHIKI KAISHA in Tokyo / Japan

Method and device for crimping mismatched fibers *

yarns

The present invention relates to a Method and device for crimping mixed fiber yarns, in which in a single fiber two polymers with different shrinkage properties eccentrically arranged. are »

In mixed fiber yarns are shrink-treated development by means of heating and swelling three-dimensional Kraus el produced, To carry out such a honti "*

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zero shrinkage treatment at high speed became mature in the Belgian patent 621 ^ 72 a process for dry heat treatment is proposed *. beat, in which air heated in a curling chamber is flowed in.

As is known, the heat treatment of synthetic ones takes place Fibers and the like by having said Brings fiber with a radiator, metal and the like in contact. In particular, it is used as such a radiator often a device in which the fiber is brought into contact with the surface of a curved plate as well as the so-called "Hohrerheilzer", in which the fiber passes through a heated cylinder is used *

Although not too many studies were carried out on procedures for gathering of mixed fibers by heating, but it was found that when using the w said fibers compared insist on using ordinary fibers some differences ·

The first difference to the usual heat treatment of the fibers consists in that said heat treatment is carried out at a very low tensile stress (for example IQ "" - * to 10 "" g / d).

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Furthermore, there is a second difference in an increase in the apparent diameter of the paser, which on the puckering occurring during the heat treatment is to be attributed to it · This makes contact between the fibers and the radiator reduced, so that the effectiveness of the Heat transfer etc6 compared to heat treatment of common fiber yarn is considerably different *

The invention will be explained with reference to the accompanying drawings:. %

Fig. 1 shows the drawing of a continuous heating device for crimping Kisch fibers dar ι

Fig. 2 represents the drawing of a well-known arcuate Tubular heater »dar}

Figures 3-7 are drawings of embodiments of the Hohrs. radiator "which in the crimping according to the invention. μ device find use «,

:. In the embodiment shown in Fig 1 apparatus 2 Hohgarn 1 is in a heated Bohr 3 by means of the feed rollers inserted, wherein verifiable form crimps md the crimped yarn 6 removed by the discharging rollers 7 is "That he"

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The yarn held can be wound up using suitable unwinding devices. The tube 3 is surrounded by a radiator k . 5 shows an insulating body. The ratio (Vl / • V2) of the speeds of the feed rollers (Vl) to the speed of the take-off rollers (V2) is greater than 1.2 and in most cases lies within a range of 1.3 to 3 * 0 »so that a so-called" over-addition "is effected.

The usual tubular heating elements, which are used for heat treatment are known from Pasern, are linear or arcuate, Fig. 1 shows an embodiment of a linear Tubular heater, while Fig. 2 is a side view of an arcuate Represents tubular heater. In the linear tubular heater, the fiber yarn comes essentially with the inner wall of said tube not in contact while in the arcuate one Radiator the fiber yarn is brought into contact with the wall of said tube. In Fig. 1 are conditions in which the yarn fiber is not brought into contact with the wall of the tube, while in Fig. 2 conditions are shown in which the yarn fiber - indicated by the dashed line - touches the wall of the tube at point G. In the usual heat treatment of yarn fibers, the yarn is under a / tensile stress (e.g. more than g / d, mostly 0.1 - 1.0 g / d). In the arched one Radiator the fiber is pressed against the wall of the pipe,

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so that the heat transfer is generally more efficient as compared with a linear tubular heater and thus the effects of the heat treatment are high.

It can be assumed that when crimping τοη mixed « fiber yarns would prevent the yarn from being pressed against the drilling wall, which would prevent the formation of crimps found that contrary to this assumption, an arc-shaped drilling heater for the formation of crimps a linear one Tubular heater is superior "

For example, under the same conditions, a virgin fiber yarn can be treated with Eohrhei «bodies of the same length, the same temperature and the smooth Diameter with curved tubular heating elements stable crimps at a higher speed than with linear Rohrerhitsera be formed·

However, it was found that the arched tubular heater still has many shortcomings

Sin "of these inadequacies consists in the minor part that the ripple develops irregularly" under * "irregular * one understands the fact that strongly g ··

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INSPECTED

curled portions and little curled portions occur at practically the same intervals. This period varies depending on the yarn speed during heat treatment and the like, but is 1-5 cm in most pollen. Although the cause of the occurrence of this uneven Ripple is not fully known, it is believed that this is due to the factor of vibration and contact with the drill wall with whom to look for Father

To clarify this question, a procedure under » seeks where the fibers passing through touch the pipe wall uniformly. Even if there is an unevenness, this is corrected according to the invention. Accordingly lit the present invention characterized

the thread running through that a tubular radiator passes through which than is bent twice in different directions and at the kneeling points necessarily with the inner wall of the Tube is brought into contact

Since in the method according to the invention, the fiber With the pipe wall in more than two parts When there is contact, there is naturally the possibility that the Frictional resistance is increased · However, it is necessary that

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the crimps are formed under a low tension of less than 10 g / &, so that it is desirable to use the To keep frictional resistance in the pipe as low as possible. This can be achieved by removing the rough inner surface of the pipe after treatment, for example with sand or in a chemical way, for example the degree of roughness is of the inner surface of the pipe advantageously 1 S - 10 S, preferably 3 S - 5 S.

The term "S" used herein means an average value when the maximum unevenness of an uneven surface (H) is measured ten times. The relation (S = (H) applies. The units represent μ .

The heating of the pipe can be effected by applying an electric current to the pipe itself or by surrounding the pipe with a gaseous, liquid or solid heat medium. You can also use high frequency heating and any other known heating method.

It is not necessary that the kink of the pipe is formed in one plane, but it can also be formed in space. The latter kind is sometimes superior to the former. Finally, it can also be an irregular one

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Shape, as in Pig. 7, which are different from the regular ones shown in Figs. 3-6 . Forms is.

The invention is described below with reference to the following Examples are described in more detail.

example 1

Nyol-6 with an intrinsic molar viscosity of 1.25 measured in m-cresol at 25 ° C. and the copolymer consisting of 90 parts by weight of nylon-6 and 10 parts by weight of polyhexamethylene isophthalamide with an intrinsic molar viscosity of 1.27 were used in conjugated in the melt with a conjugation ratio of 1: 1, spun. The resulting fiber was wound up and stretched at room temperature to 3-69 times its original length using a stretched mixing | fiber yarn of 45 d / 7 fibers received. This yarn had a very strong crimp ability, the apparent shrinkage being 85 % ^{when the yarn was treated in water at 100 °} C. for 15 minutes without load.

The drawn yarn was crimped at a temperature of 175 ° C and with a default ratio (V1 / V2) of 1.45 through a stainless tube with an inner diameter of 2 mm, a degree of roughness of the inner surface of 3 S

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"9 _

and a length of 50 cm. As for the shape of the pipe relates, a linear tube according to FIG. 1, an arcuate tube with a radius of curvature of 50 cm, according to FIG 2, a tube with two points of contact according to FIG. 3, a tube with three points of contact according to FIG. 4 and a tube with five contact points according to FIG. 5 used «Weitedtn was the maximum speed that can be used for continuous operation is determined for each tube (the yarn speed is indicated by the speed of the feed rollers). The results shown in Table I were obtained here »

Table I.

i'orm of the radiator Fig.l Maximum Feed speed jinear Fig. 2 210 m / min. Arched Fig. 3 270 m / min * Two points of contact Fig, * l 27 ^ m / min. ) three points of contact Fig. 5 280 m / min » ^? five points of contact 290 m / min ₀

As can be seen from the table above, the performance of the present invention is in the operating characteristics superior to the usual procedures *

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Example 2

The experiment was carried out under the same conditions as in Example 1 using a mixed fiber yarn and of the apparatus shown in Example 1 except that the feeding speed was 200 m / min. The crimp unevenness of the crimped fibers obtained is shown in Table II.

Table II

Shape of the radiator

Unevenness of crimp

Linear pretty much Arched relatively few Two points of contact pretty little Three points of contact little Five points of contact little

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Claims (4)

Patent claims 1. A method for forming crimps on mixed fiber yarns, in which a tubular heating element between feed and take-off rollers are arranged and the mixed fiber yarn said tube in a ratio (V1 / V2) of the feed speed (Vl) and the decrease speed (V2) of more than 1.2, characterized in that, that the thread running through a tubular heating compartment body goes through which more than two / in different Curved directions is UtL at the kinking points - ^ is brought into contact with the inner wall of the pipe. 2. Apparatus for forming crimps in mixed fiber yarns, in which a tubular heating element between feed rollers and take-off rollers, characterized in that said tubular heating element bends more than twice in different directions. 3. Apparatus according to claim 2, characterized in that the inner surface of the tubular heater is finished to have a degree of roughness from 1 S -. 10 S. - 12 - 109820/1988 4. Apparatus according to claim 2 »thereby g e k e η η ze i without t that the tubular radiator is bent into a plane. 5 · Device according to claim 2 _f, characterized in that the tubular heating element is bent in different planes. 109820/1988 Blank page