JPH03130424A - Polyester false twist crimped yarn - Google Patents

Abstract

PURPOSE:To provide the title crimped yarn nearly equal in the dyeing extent for thicker parts and thinner parts when dyed, giving no wood carving appearance, having worsted touch, made up of multifilaments with fineness variations with the length of thicker parts specified. CONSTITUTION:The objective crimped yarns made up of multifilaments with fineness variations with the number of thicker parts <=3mm in length accounting for >=80% of the total number of thicker parts formed into the filaments making up the yarns and the thicker parts dispersed uniformly within the filament yarns. The distribution of said thicker parts is e.g. expressed by the relationship (sigma is standard deviation representing the distribution; X is mean number of the thicker parts).

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention is a false twisted crimped yarn consisting of a plurality of filaments with uneven thickness, and even when dyed, the difference in shade and lightness peculiar to the yarn with uneven thickness is maintained. It does not have a heathered appearance.

This invention relates to a polyester false-twisted crimped yarn that has a plain appearance and a worsted texture.

(Prior Art) The present applicant disclosed a polyester false twisted crimped yarn having uneven thickness in the longitudinal direction of the yarn in Japanese Patent Publication No. 63-43493.

This was proposed in Japanese Patent Application Laid-Open No. 59-59934. In these crimped yarns, the thick part of the filament is stretched by twisting deformation during false twisting, creating a local slack in the filament. It is possible to give a slimy texture and a plump texture, and it has received high praise.

When these crimped yarns are dyed, when several thick parts of the single filaments line up in the cross-sectional direction of the yarn, they appear as a bound part, and the part where the thick part of the single filament does not exist appears as a shallow part, so the fabric is difficult to dye. When dyed.

It has a heathered appearance due to the difference in color. The appearance is heathered.

Although it is often used as a means of imparting surface effects to fabrics, there has been a strong desire to eliminate this heathered appearance.

However, with conventional polyester false-twisted crimped yarn that has uneven thickness, the thick part is preferentially dyed, so it is difficult to dye it in dark colors such as black with an extremely high dye concentration or with special carrier dyeing. Unless otherwise specified, it was impossible to achieve a plain appearance.

(Problems to be Solved by the Invention) The present invention solves the drawbacks of the conventional polyester false-twisted crimped yarn which has thickness unevenness, and has a worsted-like sliminess and fullness, and is substantially A technical object of the present invention is to provide a polyester false-twisted crimped yarn that can produce a woven or knitted fabric with a plain appearance.

(Means for Solving the Problems) As a result of intensive research to solve the above problems, the present inventors have found that if the length of the thick portion is specified, the distribution of the thick portions will naturally become random. The present invention was achieved by discovering that the amount of dyeing in areas and details is significantly close to each other.

In other words, the present invention is a false twisted crimped yarn consisting of a plurality of filaments having uneven thickness, and the number of thick portions having a length of 3 mm or less out of the total number of thick portions formed in the filaments constituting the yarn. accounted for over 80%.

In addition, the present invention is characterized by a polyester false-twisted crimped yarn characterized in that the thick portion is uniformly dispersed within the yarn.

The present invention will be explained in detail below.

First, in the polyester false twisted crimped yarn of the present invention, among the thick portions formed in a plurality of single filaments constituting the yarn, the number of thick portions with a length of 3 [11111 or less] Accounting for over 80% of the total number of
In addition, it is necessary that the thick portions are uniformly distributed within the yarn.

In other words, if there are many long thick parts, it is easier to align the thick parts in the cross-sectional direction of the yarn (therefore, the details are easier to align).
Since the uniform thick part is dyed as a part, it inevitably has a heathered appearance with shading. However, 2
As a result of many tests and studies conducted by the inventors, 3 mm
The number of thick parts with the following lengths is 80% or more of the total number of thick parts,
Furthermore, it has been found that when the positions of the thick portions are uniformly distributed, a woven or knitted fabric with a substantially plain appearance can be obtained.

In general, the finer and more uniform the deep dyed thick part, the more plain it looks.1 The polyester false twisted crimped yarn of the present invention can be used in fabrics where warp and weft yarns are bent into peaks and valleys, or where silk yarn is bent at stitch loops. Since it is used to produce knitted fabrics, if the thick part is 3 mm or less in length and the thick part is uniformly distributed, it will look fine in the woven or knitted state and will not be plain. It is possible to achieve this.

Next, in the present invention, the term "thick portions are uniformly distributed" means that the measured values obtained in the following manner satisfy equation (1), which will be described later.

That is, as shown in Fig. 1, one end of the yarn is fixed at the center point (A) on a mount drawn concentrically at 1 mm intervals, and all the filaments (f) constituting the yarn are fixed. ,
, f2. ... fl, ) are pasted at approximately equal intervals.

Next, the filament length is 100 mm from the center point (A).
The relative position and length of the thick part of all filaments in
Copy each filament to the thick distribution diagram shown in FIG. In the polyester false twisted crimped yarn of the present invention, as described above, the length of the thick portion of each filament shown in the thick portion distribution diagram is as follows.

More than 80% of them have a length of 3 mm or less.

Next, based on Figure 2, create a frequency distribution diagram of the thick part (Figure 3) with the horizontal axis as the distance from the center point (A) of the yarn, and based on this figure, The number of thick parts (Xi) of all filaments is determined.

The total number of thick parts (N) between yarn lengths of 100 mm is:

Since this thick part is short and distributed in an almost --like manner, the standard deviation value (σ) is within the range of 2 or less of the average value (X). That is, the distribution state of the thick part of the yarn of the present invention is as follows.

σ＜%　(X)　・・・-(1) It satisfies the following.

According to the experiments of the present inventors, the reason why a woven or knitted fabric using crimped yarn with uneven thickness is recognized as a heathered appearance to the human eye is due to the thick part formed into a single filament within a length of 10 mm. This is when the positions of the yarns are aligned and the yarn as a whole is divided into parts with many thick parts and parts with few thick parts.

In the case of the yarn of the present invention, any part can be tested.

Since the above-mentioned dispersion state is maintained, the fabric can have a plain appearance.

Furthermore, the thick part of the yarn of the present invention is dyed darker than the details, but compared to the conventional yarn with uneven thickness as described above.

It is clear that the details are dyed deeply, which makes it possible to achieve a more solid color.

To compare the difference in shade between the conventional yarn and the yarn of the present invention.

The woven fabric using the yarn of the present invention and the woven fabric using conventional yarn were dyed under the same suitable dyeing conditions (for example, Resolin Blue GRL 2% O manufactured by Bayer AG).
9w, f, 130° C. for 30 minutes using a conventional polyester dyeing method) in separate baths, and after dyeing, the cross section of each thread was observed with an optical microscope.

As a result, in the yarn of the present invention, the thick part was completely dyed and the small part was dyed in a ring shape, both of which were dyed blue.

In the conventional yarn, the thick part is completely dyed, and the details are hardly dyed.9 There is also a big difference in the dyeability of the details between the yarn of the present invention and the conventional yarn.

Next, an example of a method for manufacturing a polyester false twisted crimped yarn of the present invention will be described.

First, a highly oriented undrawn polyester yarn is used as a supply system, and this yarn is heat-treated for shrinkage in a non-contact state. If this shrink heat treatment is performed in a contact state, varying frictional tension is applied, resulting in a treatment that involves both shrinkage and elongation, which is completely different from the two yarns of the present invention.

It is necessary to perform the shrink heat treatment in a non-contact state.

When shrinking highly oriented undrawn polyester yarn.

When the temperature of the yarn is the glass transition temperature (85 to 90 t), the fiber shrinks the most, and the shrinkage tension reaches its peak value. An analysis of the conventional yarn manufacturing techniques described above reveals that the purpose of the yarn is to shrink, so the yarn is shrunk at temperatures around this range.

However, when the present inventors examined the yarn temperature during contraction in detail, they found that the temperature at which the amount of contraction is small and the contraction tension is extremely low, that is, the temperature at which the yarn crystallizes, which is not used as a shrinkage temperature in practical terms. An important point for obtaining the yarn of the present invention is to perform the heat treatment at a temperature higher than (varies depending on the degree of orientation of the highly oriented undrawn yarn = 110 to 135°C).

The yarn is subjected to a shrink heat treatment at a temperature higher than the crystallization temperature of the highly oriented undrawn yarn, and then the yarn is heated at room temperature according to the shrinkage rate of the shrink heat treatment, that is, within the natural stretch ratio in the stress-elongation curve of the shrink heat treatment system. The polyester false-twisted crimped yarn of the present invention is formed by stretching to form uneven thickness, and is further subjected to false twisting to have uneven thickness and slack filaments.

In the above false-twisting process, the multifilament yarn having uneven thickness is heated in the false-twisting process, so that the thick part is elongated preferentially to the details, resulting in a yarn with local filament slack. Become.

Due to the presence of this filament slack, the slimy feeling
Moreover, the apparent increase in yarn diameter gives a bulging feeling.

In addition, in the case of non-contact heat treatment, the actual temperature of the shrink yarn during the above-described shrink heat treatment is generally completely different from the heater setting temperature depending on the yarn speed, heater length, etc. For this reason, the temperature of the shrink heat treatment system during running is measured using a fiber temp manufactured by Transmet Inc. in the United States.

The relationship between the heater setting temperature and the actual temperature of the shrink yarn during the shrink heat treatment is 1. For example, for a highly oriented undrawn polyester yarn of 110 d/36 f (Δn = 54.6 x 10-',
Density 1.3456g/caf, glass transition temperature 8
9°C, crystallization temperature 110t) is subjected to shrinkage heat treatment at a heater temperature of 170°C (shrinkage heat treatment conditions: feed roller surface speed room/min, take-up roller surface speed 5
Qm/min, shrinkage rate 100%, heater length 600mm
), the actual yarn temperature was 98°C. Furthermore, when the heater setting temperature was set to 200° C. under the above-mentioned shrinkage heat treatment conditions, the actual yarn temperature reached 110° C. (crystallization temperature).

As mentioned above, the polyester false twisted crimped yarn of the present invention is
It is obtained by heat shrinking, stretching, and false twisting highly oriented undrawn polyester yarn, but the thick part is short and there is little difference in dyeability between the thick part and the details.

This is thought to be due to the following reasons.

That is, when a highly oriented unstretched polyester system is subjected to shrinkage heat treatment in such a way that the temperature of the yarn becomes equal to or higher than the crystallization temperature,
Crystal nuclei are uniformly formed within the highly oriented undrawn yarn, resulting in high stress against stretching.

It is thought that stress is dispersed and a short thick portion is inevitably formed.

On the other hand, a contracted highly oriented undrawn yarn heat-treated at a temperature below the crystallization temperature at which almost no crystal nuclei are formed has a low stress upon elongation and tends to cause stress concentration, resulting in the formation of a relatively long thick portion.

In addition, when shrinkage heat treatment is performed above the crystallization temperature, the formation of a folded structure of a single molecular chain is promoted and the thickness of the folded single molecular chain becomes thicker, but this is due to the movement of adjacent molecular chains to contribute to this thickening. Therefore, micro voids are formed. This small gap.

When dyeing, a large amount of dye is absorbed, but there are small voids.

Since it exists regardless of the thick part or the details, the amount of dyeing in the details is greatly improved compared to conventional thick and thin threads, and the difference in dyeing between the thick parts and the details is almost invisible.

For this reason, the length of the thick part of the single filament is 3
mm or less, and is uniformly dispersed within the thread, which is much improved compared to the difference in dyeability between the thick part and the details of conventional threads. It becomes possible to present

Further, in the polyester false twisted crimped yarn of the present invention, the filaments have slight crimps and local slack of the filaments exists throughout the yarn.

Frictional resistance is reduced, and woven or knitted fabrics using this yarn can be given a worsted-like slimy feel and a fluffy feel.

(Example) Next, the present invention will be specifically explained using examples.

Example 1 Birefringence obtained by high speed spinning: 54.6 x 10-3. Crystallinity 9.7%, density 1.3456 g/ctl
Using highly oriented undrawn polyester yarn (110d/36f) with a glass transition temperature of 89°C and a crystallization temperature of 110°C, it was processed under the conditions shown in Table 1 according to the steps of shrinkage heat treatment, cold stretching, and false twisting. A false twisted crimped polyester yarn of the present invention was obtained.

Table Note: OF ratio Niober feed ratio There were approximately two types of ratios between the thick part and the fine part of the yarn after drawing and before false twisting, which were 1.26 and 1.11.

Regarding the number of thick parts per 100 mm of arbitrary parts of this yarn, the numbers were counted every 10 mm, and the values shown in Table 2 were obtained.

No. table From Table 2, the average value of the number of thick parts is 62.

The standard deviation value (σ) was 11.05. therefore.

The condition of uniform dispersion (σ<X/4) according to the present invention is satisfied (1
1,05<15.5) Yes.

In addition, single filament thick portions with a length of 3 mm or less accounted for 98% of the total number of thick portions.

This false twisted crimped yarn was woven into a plain weave with a warp density of 90 threads/2.54cm and a weft density of 85 threads/2.54cm, and a 15%
After carrying out alkali weight loss treatment, it was dyed using a conventional polyester dyeing method using Diamond Thread KB-3E 2% O, W, F manufactured by Mitsubishi Chemical Industries.

The obtained fabric had a plain appearance, and had a worsted-like slimy feel and fluff.

Comparative Example 1 Polyester false twisted crimped yarn was processed in the same manner as in Example 1 except that the heater setting temperature was 160°C and the actual yarn temperature was 91°C under the shrinkage conditions in Table 1 of Example 1. was manufactured.

The ratio between the thick part and the fine part of the yarn after drawing and before false twisting was one, and the ratio was 1°4.

Although the resulting false twisted crimped yarn has a thick portion with a length of 2 to 3 mm, most have a length of 10 to 30 mm.

Thick portions and fine details were clearly formed along the longitudinal direction of the yarn, and the thick portions were not uniformly dispersed within the yarn.

Also, when the fabric obtained from this yarn is dyed.

It has a heathered appearance due to the difference in color.

(Effect of the invention) Although the polyester false twisted crimped yarn of the present invention is formed of filaments having uneven thickness, the woven or knitted fabric obtained from this yarn after dyeing has a substantially plain color tone. It has a slim appearance and a fluffy texture similar to that of worsted wool.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram showing a yarn disassembly method for specifying the relative position of the thick part of the polyester false twisted crimped yarn of the present invention;
The figure is a thick part distribution diagram transcribing the relative positions of the thick parts obtained by yarn decomposition in Fig. 1, and Fig. 3 is a thick part distribution diagram. FIG. 3 is a frequency distribution diagram of thick portions obtained based on FIG. 2;

Claims (1)

[Claims] (1) A false twisted crimped yarn consisting of a plurality of filaments having uneven thickness, in which the number of thick portions with a length of 3 mm or less is 80 out of the total number of thick portions formed on the filaments constituting the yarn.
% or more, and the thick portion is uniformly dispersed within the yarn.