JPH09170126A - Processing of cellulosic fiber yarn - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain processed cellulosic fiber yarns capable of imparting durable knitted stitch shapes and enabling to obtain a fabric having an uneven surface touch and a characteristic touch by forming a formaldehyde-containing knitted fabric from cellulosic fiber yarns, thermally treating the knitted fabric to crosslink the cellulose molecules each other, and subsequently unknitting the knitted fabric. SOLUTION: This method for processing cellulosic fiber yarns comprises forming a formaldehyde (the concentration of the formaldehyde is preferably 1-20%)-containing knitted fabric from cellulosic fiber yarns such as cotton, hemp or rayon, thermally treating the formed knitted fabric at a temperature of 100-180 deg.C for 0.1-10min to crosslink cellulose molecules each other, and subsequently unknitting the knitted fabric.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a processing method for imparting a durable stitch-like form to a cellulosic fiber yarn used for clothing and materials.

[0002]

2. Description of the Related Art Conventionally, various fiber processing methods have been devised in order to meet consumers' diversified fashion demands. As a method of coping with these, synthetic fibers such as polyester fibers and nylon fibers are used for the steps of knitting, heat treatment, and unknitting, by utilizing their thermoplasticity, to form a durable knitted form. The method of processing fibers for imparting a wide range of processes is widely used under the name of the knit de knit method, and due to this knitted form, we have obtained fabrics with a unique surface variation and texture. However, since the cellulosic fiber yarn does not have thermoplasticity, this method cannot be used, and the product field using the cellulosic fiber yarn cannot be expanded.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to obtain a processing method for imparting a durable knitted form to a cellulosic fiber yarn. It is what

[0004]

The present invention achieves the above object and has the following configuration. That is, the present invention is characterized in that after forming a formaldehyde-containing knitted fabric using a cellulosic fiber yarn, it is heat-treated to crosslink the formaldehyde between cellulose molecules, and then the knitted fabric is unknitted. The gist is a method of processing a cellulosic fiber yarn.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. Cellulosic fiber yarns to be processed by the method of the present invention include natural fibers such as cotton and hemp, regenerated cellulose such as rayon and polynosic, and semi-synthetic fibers such as acetate and triacetate, at least 10% or more, preferably 5 or more.
It means a fiber yarn containing 0% or more. As other fibers, synthetic fibers such as polyester fibers and nylon fibers may be mixed.

In the present invention, first, a knitted fabric containing formaldehyde is formed by using the above-mentioned cellulosic fiber yarn and heat-treated to crosslink formaldehyde between cellulose molecules. When forming the knitted fabric,
Usually, a single circular knitting machine having a diameter of 3 to 5 inches is used for knitting, and the cellulosic fiber yarn is knitted. In this knitting process, the knitted shape given to the cellulosic fiber yarn is fixed through a post process, so that the gauge, knitting degree, knitting tension, etc. of the single circular knitting machine are adjusted to match the desired stitch. Set the conditions. Selecting a simple knitted fabric as described above in this step is effective for efficient handling and unknitting in the subsequent step.

By adding formaldehyde to the knitted fabric,
In order to cross-link formaldehyde between cellulose molecules by heat treatment, it is possible to carry out by normal pad-nip → drying → baking process by resin processing method, but formaldehyde can be directly cross-linked between cellulose molecules in a gas phase state. It is more rational to use the vapor processing method with formaldehyde.

When adopting the vapor processing method, first, the moisture content of the knitted fabric is adjusted to be uniform. At this time, the moisture content of the knitted fabric must be 1 to 50%, and the moisture must be evenly distributed in the knitted fabric. If the moisture content of the knitted fabric is 1% or less, the formaldehyde used in the next step will not be sufficiently adsorbed on the knitted fabric, and if it is 50% or more, the acid catalyst used may cause embrittlement of the knitted fabric. It will come, so be careful. Also note that if moisture is not evenly distributed in the knitted fabric, formaldehyde gas will not be adsorbed uniformly. To make the moisture content uniform,
Although any means may be used, it is usually preferable to use a method of leaving the knitted fabric in a constant temperature and constant humidity chamber for 24 hours or more.

After adjusting the water content, it is exposed to formaldehyde in a gas phase and heat-treated to carry out gas phase processing to crosslink the formaldehyde between cellulose molecules. At the time of vapor phase processing, a vapor phase processing apparatus having an atmospheric pressure closed reaction chamber, a formaldehyde gas supply means such as a nozzle, and a heating means such as a heater can be used. A
A vapor phase processing apparatus manufactured by TP (American Textile Processing Co.) (see JP-A-5-117958) may be used. The formaldehyde gas concentration in this vapor phase processing apparatus is preferably in the range of 1 to 20%, and if it is 1% or less,
Even if the cross-linking reaction becomes insufficient and it exceeds 20%, the effect does not increase so much.

The catalyst used for the cross-linking reaction may be subjected to a gas phase treatment after the catalyst solution has been padded on the knitted fabric, or the catalyst solution or the liquefied catalyst may be vaporized or misted to form a knitted fabric. It may be adsorbed. Regarding the type of the catalyst, when the catalyst solution is padded in advance on the knitted fabric, the same catalyst as that used in the conventional resin processing, for example, a metal salt of an acid such as zinc nitrate, a Lewis acid, and a Bronsted acid can be used. Further, when vaporizing, a volatile acid having a low boiling point such as hydrogen chloride is desirable.

With respect to the catalyst concentration, the range of 0.1 to 3.0% is desirable when treating with gas. When the gas concentration is 0.1% or less, the crosslinking reaction becomes insufficient, and even when it is 3.0% or more, the effect cannot be further improved. When the catalyst is attached by padding, the catalyst concentration is 5-10.
The range of 0 g / liter is desirable, and when the concentration is 5 g / liter or less, the crosslinking reaction becomes insufficient and 100 g / liter
Even if the volume exceeds liters, no further effect can be obtained.

After adsorbing the formaldehyde gas, a heat treatment is carried out to carry out a cross-linking reaction.
The crosslinking reaction can be completed by performing the treatment at a temperature in the range of 80 ° C. for 0.1 to 10 minutes.

Then, in the present invention, the cellulose fiber yarn is unwound and wound from the knitted fabric in which the crosslinking reaction is completed. At this time, pay attention to the tension at the time of unraveling so that the stitch-like shape given to the cellulosic fiber yarn is not strongly deformed and that the deformation between fibers does not vary.

According to the above-mentioned method, when forming a knitted fabric containing formaldehyde, the formaldehyde treatment is performed after knitting the knitted fabric. There is no problem even if a knitted fabric containing formaldehyde is formed by knitting using the contained yarns.

The cellulosic fiber yarn provided with the knitted form can be used for knitting or woven fabric like the ordinary fiber yarn. When thermoplastic synthetic fibers such as polyester fibers and nylon fibers are mixed as other fibers, when the knitted fabric is heat-treated, it is combined with the set effect of these thermoplastic synthetic fibers to form a knitted shape. This is convenient because it also has the effect of increasing durability.

[0016]

As in the method of the present invention, when a knitted fabric containing formaldehyde is formed using cellulosic fiber yarns and heat treated to crosslink formaldehyde between cellulose molecules, the yarns are When the knitted fabric is firmly fixed in its state and the knitted fabric in such a state is unknitted, it becomes possible to obtain a cellulosic fiber yarn in which the knitted form is firmly fixed.

[0017]

EXAMPLES Next, the present invention will be described in more detail with reference to Examples. The durability of the knitted form formed on the cellulosic fiber yarns in Examples was evaluated by the following method. (1) Durability of stitch-like form A circular knit single jersey machine (kettle diameter 30 inch, number of needles 2) using a cellulosic fiber yarn provided with a stitch-like form.
640 pieces, 28G / G) knitted in a plain weave structure, width 18
A knitted fabric having a weight of 0 cm and a basis weight of 250 g is obtained. Next, after scouring and relaxing, boil off (white) at 100 ° C with a jet dyeing machine.
After processing for 30 minutes, it was set in a tenter at 150 ° C. for 30 minutes to obtain a knitted fabric having a width of 150 cm and a basis weight of 240 g. Subsequently, the unevenness of the surface of the knitted fabric was evaluated relative to the knitted fabric sample after 1-time home washing, 10-time wash and unwashed according to JIS L-0217 by the following three grades by visual observation. ○ Good △ Normal × Poor

EXAMPLE 1 Using cotton (100%) 30/1, a tubular knitted fabric was knitted by a circular knit single jersey machine (kettle diameter 3-2 / 1 inch, number of needles 280). By leaving this tubular knitted fabric in a constant temperature and humidity room of 20 ° C x 65% for 24 hours, the moisture content of the knitted fabric is increased.
Adjusted to 7.0%.

Next, after exposing the knitted fabric to formaldehyde gas for 1 minute under the following vapor phase processing condition 1 using a gas phase processing apparatus of atmospheric pressure closed type having a gas blowing apparatus and a heating apparatus for reaction incorporated therein. Heat treatment was performed at 120 ° C. for 2 minutes. Gas-phase processing conditions 1 Formaldehyde gas 7.0% Sulfurous acid gas (catalyst) 2.0% After that, the knitted fabric after the above treatment was wound while being unknitted to obtain a knitted fixed cotton yarn according to the present invention. .

For comparison with the present invention, 120 ° C. × 2 instead of vapor-phase processing with formaldehyde in this example.
A textured yarn for comparison was obtained by the same method as in this example except that the dry heat treatment was performed for 1 minute.

The performances of the present invention and the textured yarn for comparison were evaluated, and the results are also shown in Table 1.

[0022]

[Table 1]

As is clear from Table 1, the knitted fabrics of the comparative examples did not have unevenness formed on the surface of the knitted fabric, which had a clear knitted shape, even after unwashed, and no unevenness was already observed after one wash. However, the knitted fabric of the present invention had irregularities on the surface even after washing 10 times.

[0024]

According to the present invention, it becomes possible to impart a durable stitch form to a cellulosic fiber yarn,
By using this, it is possible to obtain a fabric having an uneven surface feeling and a unique texture.

Claims (1)

[Claims] 1. A method for forming a knitted fabric containing formaldehyde using a cellulosic fiber yarn, followed by heat treatment to crosslink the formaldehyde between cellulose molecules, and then to unknit the knitted fabric. Processing method of cellulosic fiber yarn.