JPS62191525A - Production of polyester crimp yarn having irregular thickness - 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] <Industrial Application Field> The present invention has extremely large differences in fineness and crimp in the longitudinal direction of the yarn, and also has a difference in heat shrinkage between large fineness portions and fine fineness portions. A polyester that has a rich texture even in plain white fabrics, making it possible to obtain bulky and soft woven or knitted fabrics, as well as products with a clean surface without grain-like wrinkles between concave and convex areas. The present invention relates to a method for manufacturing crimped yarn.

<Prior art> Conventionally, a method for manufacturing a polyester yarn having a large fineness portion and a fine fineness portion along the longitudinal direction of the yarn is already known. ″3～10
An undrawn yarn of about ×10-3 was used as the supply system.

A method of incompletely stretching this, etc., has been proposed.

However, the polyester yarn having thick and thin parts obtained in this way is
On the other hand, since the degree of orientation of the large fineness portion is too low, it has the disadvantage that it is easily bent by heat processing such as a false twisting process or a dyeing process.

Therefore, the birefringence (Δn) is 15X10-' to 80X1
A method for producing thick and thin polyester yarn using a highly oriented undrawn yarn of about 0 to 3 as a supply system is also known. However, such highly oriented undrawn yarns are disclosed in Japanese Patent Publication No. 38-2018, Japanese Patent Publication No. 38-2019,
Special Publication No. 39-9175, Publication No. 42-27563
As described in the publication, mechanical methods of periodically deforming using deforming rollers and notched rollers, and methods of manufacturing by stretching at a stretching ratio lower than the natural stretching ratio, do not produce heat during processing. Although the problem of embrittlement is eliminated,
Since the outer diameter of the thick part cannot exceed the outer diameter of the supply system, only yarn with a small thick/fine ratio can be obtained, and the disadvantage is that the thick/fine effect of the yarn cannot be expressed on plain white fabrics before dyeing. There is.

<Problems to be Solved by the Invention> The present invention is intended to eliminate the drawbacks of the conventional manufacturing method as described above, and its purpose is to:

It is possible to obtain a bulky woven or knitted fabric that has clear thick and thin lines and is visually and tactilely uneven even in a plain white fabric, and the difference in heat shrinkage between the large fineness part and the fine fineness part. The goal is to produce polyester crimped yarn with a clean product surface by bringing the materials close together.

<Means for solving the problems> That is, 9 The present invention has a birefringence (Δn) of 15 x 10
- A highly oriented undrawn polyester yarn of 3 to 80 x 10-3 is subjected to a relaxation heat treatment, and then water or an aqueous liquid is intermittently applied to the yarn, followed by continuous hot stretching in a non-contact state with a heating device. The gist of the present invention is a method for producing a polyester crimped yarn having a thick and thin shape, which is characterized in that it is subsequently subjected to a false twisting process.

Hereinafter, one aspect of the present invention will be explained in detail.

First, in the method of the present invention, the birefringence (80) is 15X
A highly oriented undrawn polyester yarn of 10-3 to 80×10-3 is subjected to a relaxation heat treatment. In this case, if the birefringence (Δn) of the highly oriented undrawn polyester yarn is less than 15X10-3, it is not preferable because it may melt during relaxation heat treatment or the large fineness portion of the yarn may become brittle during post-processing such as dyeing process. . On the other hand, when the birefringence (Δn) exceeds 80 x 10-', the degree of orientation approaches that of the drawn yarn, the amount of shrinkage during relaxation heat treatment becomes extremely small, and it is difficult to increase the thick-to-thin ratio of the yarn. I can't do it, so it's not appropriate.

When the highly oriented undrawn polyester yarn is subjected to relaxation heat treatment, the relaxation rate is such that the difference between the yield stress during room temperature stretching and the yield stress during high temperature heating stretching of the relaxation heat treated yarn is greater than that in the supply system. The relaxation rate may be as long as the relaxation rate, and the larger the relaxation rate, the larger the fineness ratio can be. However, it is practically preferable to set the relaxation rate to 30 to 150%, since it is related to the heat shrinkage performance of the supply system. Note that the relaxation rate here refers to the ratio of the difference between the supply speed and the withdrawal speed to the withdrawal speed, expressed as a percentage.

In addition, the treatment temperature for the relaxation heat treatment depends on the relaxation rate and yarn speed, but the relaxation rate is 30 to 150%, and the yarn speed is 80 to 200 m/m.
In the range of in, it is preferable to set it as 120-230 degreeC.

Note that the relaxation heat treatment of the highly oriented undrawn polyester yarn is preferably performed without contacting a heating device. When the relaxation heat treatment is performed by running the yarn in contact with a heating device, tension is applied to the single filament due to the contact resistance, and the single filament cannot freely contract, causing the yarn to become oriented. This is because it causes unevenness and crystallinity.

-5= Next, in the second method of the present invention, water or an aqueous liquid is intermittently applied to the yarn subjected to the relaxation heat treatment. Here, the aqueous liquid is one containing 50% by weight or more of water,
Examples of substances outside the waterside include surfactants, dyeing aids, rust preventives, and the like.

How to intermittently attach water or an aqueous liquid (hereinafter referred to as liquid) to threads that have been subjected to relaxation heat treatment 5. Method of attaching water or an aqueous liquid (hereinafter referred to as liquid) using a gear-type deformed rotating roller with protrusions on the roller surface, intermittent attachment using an electromagnetic solenoid Any method may be used as long as the liquid is brought into contact with the roller surface through reciprocating motion, or the liquid can be intermittently attached to the yarn at an appropriate length. In particular, microcomputers and random pulse generation may be used. The combined use of units allows the liquid to be deposited at random intervals and lengths.
Particularly suitable.

Then, the yarn to which the liquid has been intermittently applied as described above is continuously subjected to hot stretching without contact with a heating device. In this case, when the yarn is brought into contact with a heating device and hot-stretched, the liquid evaporates, and the areas to which the liquid has adhered receive the same thermal effect as the areas to which no liquid has adhered, resulting in the same stretching. 2. It is not possible to obtain a yarn with a large fineness ratio, which is the object of the present invention. The temperature of the heating device in this case depends on the yarn speed, but for example, the yarn speed is 80 to 200 m/min.
In the range of 140°C to 230°C, the temperature is preferably 140°C to 230°C.

Further, the stretching ratio Dr in hot stretching is preferably (1+S/100) to 1.5 (1+S/100) with respect to the relaxation rate S (%) of the relaxation heat treatment. That is, the stretching ratio Dr is (1+
If the stretching ratio D is less than 1.5 (1+S/100), the large-to-fine fineness ratio will be small due to insufficient stretching of the non-liquid-adhesive part. This is because it becomes thinner.

In this way, the part to which the liquid has adhered is not affected by heat during hot stretching and has resistance to stretching, resulting in a large fineness part, while the part to which the liquid has not adhered is subjected to heat action and is sufficiently stretched to become fine. It becomes the fineness part.

Furthermore, in the third method of the present invention, after hot stretching as described above, one false twisting process is performed. The false twisting process here not only crimps the yarn, but also reduces the difference in heat shrinkage performance between the large fineness portion and the fine fineness portion, which is an important objective of the present invention. For this reason,
In the false twisting process.

It requires a higher heat action than the heat receiving effect received during hot stretching. Therefore, the heating device for false twisting should be set to a higher temperature than that for hot stretching, or if the temperature is about the same,
The yarn is made to run in contact with the heating device. For example, yarn speed 80~
In the range of 200 m/min, 160°C without contact
-240°C, preferably 150°C - 240°C in contact state.

In addition, the number of false twists T (times/m) in the false twisting process is 2800
0/rr5 (D is the denier of the supply system) or less is preferable, and if the number of false twists T (times/m) exceeds 28,000 Δ threads, yarn breakage will occur, which is not preferable for operation. On the other hand, if the number of false twists is too low, there will be less crimp and the bulkiness will be reduced, so the number of false twists T (times/m) is 1o.
It is preferable to set it as ooo/g or more.

The overfeed rate during the false twisting process may be appropriately selected within a range where the thick fineness part is not stretched more than necessary and yarn breakage does not occur in the overfeed state, and preferably an overfeed rate of around 0% is appropriate. It is.

FIG. 1 is a process schematic diagram showing an example of the manufacturing process of the method of the present invention. In FIG. 1, the highly oriented undrawn polyester yarn F pulled out from the spool 1 passes through the guide 2, passes through the feed roller 3, enters the first heating device 4, and is placed between the feed roller 3 and the first delivery roller 5 at a predetermined position. It is thermally shrunk at a relaxation rate of , and liquid is intermittently applied via the first pre-heli roller 5 to the liquid applying device 6 according to random signals from a microcomputer. Subsequently, it is hot stretched in a non-contact state by a second heating device 7 at a predetermined stretching ratio between the first delivery roller 5 and the second delivery roller 8, and heated by a false twisting device 10 after passing through the second delivery roller 8. At the same time, it is heat-fixed by the third heating device 9, passed through the third delivery roller 11, and then wound up by the winding roller 12 into a package 13 as a thick and thin crimped yarn.

The polyester in the present invention is a general term for polyesters containing ester bonds in the molecular chain, typified by polyethylene terephthalate, and also includes modified polyesters containing a third component such as isophthalic acid and paraoxyethoxybenzoic acid. .

Further, the birefringence (Δn) is a value measured by an interference fringe measurement method using a polarizing microscope compensator.

<Function> As described above, in the three methods of the present invention, it is possible to make the large fineness portion larger than the fineness of the supply system by the relaxation heat treatment. Since the material is hot-stretched by applying a liquid intermittently, the portion to which the liquid is applied is not subjected to heat action during hot-stretching and is not deformed by stretching, as shown in Figure 2a. The part becomes a thick large fineness part, while the part to which no liquid is attached becomes a fine fineness part as shown in FIG.

In the present invention, large fineness portions and fine fineness portions are alternately formed in the longitudinal direction of the yarn in this manner, and a yarn with a large fineness ratio can be obtained.

Furthermore, since the thick and thin yarn is crimped by false twisting, it has a high bulkiness. In this case, it is thought that since twisting occurs preferentially in the fine-grained portion, the crimp in the fine-grained portion becomes stronger. In addition, it reduces the difference in heat shrinkage performance between the large fineness portion and the fine fineness portion during the 5-false twisting process.

A crimped yarn can be obtained that can be made into a product with a clean surface.

<Examples> The following two methods of the present invention will be specifically explained with reference to Examples. In the following examples, the yarn diameter ratio of the thick fineness part and the fine fineness part is:
The yarn diameter of the large fineness part and fine fineness part was set to 3 under a load of 0.3g/d.
00 (twists/m) was applied and measured using a microscope with a scale, and it represents the ratio of the yarn diameter of the large fineness section to the yarn diameter of the fine fineness section.

Example Highly oriented undrawn polyester yarn 110 d / 36 f having a birefringence (Δn) of 51 XiO-3 obtained by high-speed spinning,
According to the process shown in FIG. 1 and the processing conditions shown in Table 1, a crimped yarn having a thick and thin thickness was produced by the method of the present invention.

At this time, a false twisting spindle was used as the false twisting device.

The crimped yarn obtained in Table 1 was a crimped yarn having a large fineness portion and a fine fineness portion at one corner of a predetermined length in the longitudinal direction.

When the yarn diameter ratio of the thick fineness portion and the fine fineness portion was examined, the yarn diameter ratio was 1.3.

This thick and thin crimped thread has a warp density of 67 threads/2.54cm.
.

When weaving a plain weave with a weft density of 64 fibers/2.54 cm and refining it to create a plain white product, the large fineness areas formed convex parts, giving it a slab-like appearance, and the areas other than the convex parts were normal. It has a bulky and soft feel unique to crimped yarn.

The product surface had a clean appearance without any unnatural wrinkles.

<Effects of the Invention> As described above, in the method of the present invention, a specific highly oriented undrawn polyester yarn is subjected to relaxation heat treatment, and then a liquid is intermittently applied thereto, followed by hot stretching.

Since it is subjected to false twisting, the fineness part can be made larger than the fineness of the supply system by relaxing heat treatment, and the fineness part is further drawn and made thinner than the fineness of the supply system by hot stretching. . Therefore, the woven or knitted fabric obtained from the crimped yarn according to the method of the present invention can be made into a product that is extremely uneven both visually and tactilely in the plain white color before dyeing.

Moreover, the method of the present invention develops thick and thin by hot stretching = 13
- Since it adopts a structure in which the twisted yarn is subjected to a false twisting process, the effect of crimp can be fully reflected in the product.

Furthermore, by heating during false twisting, it is possible to reduce the difference in heat shrinkage performance between the large fineness portion and the fine fineness portion, resulting in a bulky product with a clean surface.

In addition, since the method of the present invention reveals uneven fineness of yarn due to intermittent liquid adhesion, the adhesion of liquid can be arbitrarily adjusted by using a microcomputer, and the pattern pattern and wind pattern of woven or knitted fabrics can be adjusted as desired. It is possible to easily produce a crimped yarn whose binding can be freely changed. Furthermore, in the method of the present invention, a highly oriented undrawn yarn with a birefringence (Δn) of 15×10 −3 or more is used as a supply system, so the obtained crimped yarn has a highly oriented yarn even in the large fineness portion. It also has the advantage that it does not become brittle due to heat processing such as false twisting.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a process schematic diagram showing an example of the manufacturing process of the method of the present invention, and FIG. 2 is a schematic diagram of the external appearance of a thick and thin crimped yarn produced by the method of the present invention.

Claims (1)

[Claims] 1. Birefringence (Δn) is 15×10^-^3 to 80×10
The highly oriented undrawn polyester yarn of ^-^3 is subjected to a relaxation heat treatment, and then water or an aqueous liquid is intermittently applied to the yarn, followed by continuous hot stretching in a non-contact state with a heating device, and then temporarily stretched. A method for producing a thick and thin polyester crimped yarn, which is characterized by twisting the yarn. 2. A method for producing a thick and thin polyester crimped yarn according to claim 1, wherein the draw ratio Dr in hot drawing satisfies the following formula. (1+S/100)≦Dr≦1.5 (1+S/100)
However, S is the relaxation rate (%) during relaxation heat treatment.