JPH08188962A - Method for imitation linen finishing of cellulosic fiber - Google Patents

Abstract

PURPOSE: To impart a hempen touch feeling rich in crispiness and bending resilience to a cellulosic fiber by impregnating the cellulosic fiber with an alkaline solution, dry heat-treating the impregnated fabric and then carrying out the low-temperature mercerizing treatment with an alkaline solution containing sodium zincate. CONSTITUTION: A woven fabric of a cellulosic fiber such as cotton is padded in a solution of sodium hydroxide, squeezed with a mangle, then dried, subsequently dry heat-treated with a pin tenter and further sufficiently washed with a soaper to complete the pretreatment. The low-temperature mercerizing treatment of the pretreated fabric with a solution of sodium hydroxide containing sodium zincate is carried out to impart a touch feeling close to that of hemp thereto.

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 hemp-like texture to cellulosic fibers.

[0002]

2. Description of the Related Art Pseudo hemp processing for cellulose fibers is
It has been actively studied since ancient times and is being implemented by various methods. The conventional pseudo-hemp processing methods are roughly classified into finishing processing methods and chemical modification methods.

As the former method, a method of impregnating a polyester resin, a urethane resin, a polyester acrylate resin, etc. and heat-treating is generally used. The methods using these synthetic resins are widely practiced because they are relatively easy to process, but the texture effect as a hemp tone is poor, and most of them only give hardness and are peculiar to hemp. The sharpness, elasticity, etc. are hardly given. In addition, some methods have also been carried out in which colloidal silica is used in combination to give a sharp feeling, but even in this case, the feel of the colloidal silica is only slightly improved due to the lubricating effect, and it is more likely that the texture is malignant. It is far from it. These methods are not sufficient in terms of texture durability.

Other methods using finishing agents include a method of coagulating with formalin using casein or gelatin, or a method of coagulating with sulfuric acid using viscose, but the processing method is complicated. However, since the effect of the texture is not sufficient, it is hardly implemented at present.

As the latter method of chemical modification, there is a method of using a concentrated solution of sulfuric acid or zinc chloride. In this method, cellulose is semi-dissolved and parchmented, and a very hard texture can be imparted. However, since the texture obtained by this method is significantly different from hemp tone, the organdy is generally used. It is called processing and is distinguished from pseudo hemp processing.

Another method by chemical modification is a low temperature mercerizing method, which is a method of performing mercerizing processing at a low temperature of 0 to -10 ° C. In this case, the low temperature treatment increases the swelling property of the cellulose, and the texture is harder than the treatment at room temperature. From the aspect of the texture, the texture is relatively hemp texture in the conventional method. You can get a close one, but the biggest drawback is that the durability of the texture is poor,
The texture will be lost after several washes.

Therefore, the applicant of the present invention discloses, as a method for obtaining a hemp texture having washing durability, in Japanese Patent Publication No. 6934/1994, "Cellulosic fibers are impregnated with an alkaline solution and then subjected to a dry heat treatment, and after that, Proposed is a pseudo-hema processing method for cellulosic fibers, characterized in that the fibers are mercerized at low temperature. According to this method, the durability of the texture of hemp was considerably excellent as compared with the conventional method, but it was not sufficiently satisfactory.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and imparts to the cellulosic fibers a very hemp-like texture with satisfactory wash durability and excellent washing durability. The purpose of the present invention is to obtain a processing method.

[0009]

The present invention achieves the above-mentioned object and has the following configuration. That is, the present invention is characterized in that the cellulosic fiber is impregnated with an alkaline solution, then subjected to dry heat treatment, and then the fiber is subjected to low temperature mercerization treatment using an alkaline solution containing sodium zincate. The pseudo-linen processing method of is the gist. Hereinafter, the method of the present invention will be described in detail.

The method of the present invention has been researched and developed with a focus on the texture of hemp tone obtained by the low temperature mercerizing treatment, with the aim of further enhancing the effect. In the method of the present invention, in order to increase the sensitivity of the cellulosic fiber to alkali at a high concentration, the surface of the fiber is previously made into oxycellulose, and then the fiber is subjected to a low temperature mercerization treatment using an alkaline solution containing sodium zincate. By maximizing the alkali swelling property, it is intended to impart a linen-like crispness and hardness feeling with good durability.

In the method of the present invention, first, the cellulosic fibers are impregnated with the alkaline solution, and then the dry heat treatment is performed.
The term "cellulosic fiber" as used in the present invention mainly means cotton, but the method of the present invention may be a cellulosic fiber other than cotton, that is, rayon, hemp or the like. Regarding hemp, the name hemp tone is not always correct, but it is included in the scope of application of the method of the present invention because the feeling of sharpness can be further emphasized. The fiber to be treated may be in the form of woven fabric or knitted fabric, and the method of the present invention can be applied in the form of yarn.

Alkali agents that can be used in the pretreatment of the present invention include sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium carbonate, potassium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, etc. Any aqueous solution can be used as long as it exhibits relatively strong alkalinity. From an industrial point of view, it is most advantageous to use sodium hydroxide.

Cellulosic fibers are impregnated with alkali using such an alkaline solution, and in the case of a cloth, it is pressed and squeezed with a mangle or the like, dried, and then subjected to dry heat treatment. The effect of the present invention is great when the concentration of alkali used is in the range of 1 to 10% owf of sodium hydroxide after squeezing. Regarding the processing conditions for dry heat treatment, when using Labo pin tenter in a continuous form such as cloth,
The treatment is performed at 180 ° C. for about 20 seconds to 5 minutes.

After the above treatment, the residual alkali is removed, and then a mercerization treatment is carried out with an alkali solution containing sodium zincate (it is possible to add urea). For this mercerizing treatment, a well-known mercerizing processing method which is usually carried out on a cloth or a thread is applied. In the present invention, however, a low temperature mercerizing treatment for increasing the curing action is aimed especially at the linen-like crisp feeling. Is effective. The temperature of the low temperature mercerizing process may be 0 to -10 ° C,
The lower the temperature, the greater the hardening. In particular, the treatment at -5 to -10 ° C is more effective.

In the low temperature mercerizing treatment, when the low temperature mercerizing treatment is carried out using an alkaline solution containing sodium zincate as in the method of the present invention, the low temperature mercerizing treatment is carried out as compared with the method of carrying out the low temperature mercerizing treatment using an alkaline solution containing no sodium zincate. It is possible to obtain a hemp-like texture that is moderately hard and has a strong sense of sharpness, and the washing durability of that texture can be dramatically improved. Furthermore, by adding urea to the treatment liquid, it is possible to obtain a sharpness closer to that of hemp.

[0016]

As in the present invention, by preliminarily subjecting the cellulosic fibers to the dry heat treatment after applying the alkali agent, the swelling action is increased in the subsequent treatment with the alkaline solution containing sodium zincate. Although it is not always clear why a sharp texture similar to that is obtained is obtained, the present inventors presume as follows.

That is, by impregnating an alkaline solution and performing a dry heat treatment at a high temperature, a part of the cellulosic molecules on the fiber surface is hydrolyzed or oxidized, and a carbonyl group, an aldehyde group or the like is reduced in an end group or a molecule. The number of sexual groups increases,
So-called oxycellulose is considered to occur. This reducing group is very unstable to a high concentration of alkali, and therefore, in the subsequent treatment with an alkaline solution containing sodium zincate, the reducing group is the starting point of alkaline swelling and partial destruction. Therefore, it is considered that the treatment effect is remarkably improved and the durability is irreversibly excellent.

Further, the method of the present invention has a very small decrease in strength as compared with the case of oxidizing cellulose by using periodate, sodium chlorite, sodium hypochlorite, hydrogen peroxide and the like. I also have. The reason for this is not clear, but it can be inferred as follows. That is, the mechanism of oxidation of cellulose by alkali is as follows:
Oxidation by taking in oxygen in the air is dominant, and since the dry heat treatment is performed immediately after alkali impregnation,
During the dry heat treatment, the surface layer of the fiber, which has a large contact with oxygen in the air, is intensively oxidized, so that the influence on the inside or the crystal part of the fiber is small, and as a result, in the case of the method of the present invention, other It is considered that the reduction in strength is less than that of the oxidation method of.

[0019]

EXAMPLES Next, the method of the present invention will be described by way of examples. The measurement and evaluation of the performance of the cloth in the examples was carried out on the sample after processing and the sample after washing three times according to JIS L-0217 (103 method). Was conducted by the following method. (1) Hardness of texture The total hand value was measured and evaluated according to JIS L-1096. (2) Sharpness Sensitivity tests performed the following three relative evaluations. ◎: Very good ○: Good △: Normal

Example 1 A cotton fabric after scouring (a plain weave using a 10-yarn single yarn for both warp and weft, weaving density 38 warp / inch, weft 41 thread / inch) was padded with a sodium hydroxide 20 g / liter solution and mangled. After squeezing with a pickup of 75%, it was dried. Then, after performing a dry heat treatment at 170 ° C. for 1 minute with a lab pin tenter, it was sufficiently washed with a soaper to complete the pretreatment.

Next, the pretreated cloth was treated with a laboratory mercerizing frame to remove sodium hydroxide 15 at high temperature (80 ° C.).
% Zinc oxide 0.3% in the solution obtained,
Mercerize for 1 minute at -6 ℃,
Completed the main processing. The woven fabric obtained by the method of the present invention thus obtained has a surprisingly sharp feeling and repulsion as described below, and has a texture very close to that of a real hemp woven fabric.
The texture was also very durable.

For comparison with the method of the present invention, in this example, no pretreatment was carried out, and the same procedure as in this example was carried out except that sodium zincate was removed from the alkaline solution during the low temperature mercerizing treatment. A processed fabric for comparison (Comparative Example 1) was obtained. Further, in this example, when the mercerization treatment was performed, sodium zincate was omitted from the alkaline solution, and the mercerization treatment was performed at room temperature. 2) was obtained. Further, in this example, when the low temperature mercerization process was performed, the processing was performed in the same manner as in this example except that sodium zincate was omitted from the alkaline solution, and a processed fabric for comparison (Comparative Example 3) was obtained.

The performances of the present invention and the processed fabric for comparison were measured and evaluated, and the results are shown in Table 1.

[0024]

[Table 1]

As is clear from Table 1, by treating with an alkaline solution containing sodium zincate, the texture is moderately hardened and the sharpness is increased, and the washing durability is excellent. I understand.

Example 2 A cotton fabric after scouring (a plain weave using a 10th single yarn for both warp and weft, weaving density 38 warp / inch, weft 41 thread / inch) was padded with a sodium hydroxide 20 g / liter solution and mangled. After squeezing with a pickup of 75%, it was dried. Then, after performing a dry heat treatment at 170 ° C. for 1 minute with a lab pin tenter, it was sufficiently washed with a soaper to complete the pretreatment.

Next, a high temperature (80 ° C.) sodium hydroxide 1 was applied to the pretreated cloth by using a laboratory mercerizing frame.
Dissolve 0.3% zinc oxide in a 5% solution, then add 10% urea.
% In a solution obtained by dissolving 1% at a low temperature of -6 ° C.
This process was completed by performing a mercerization process for a minute. The woven fabric obtained by the method of the present invention thus obtained was provided with a surprisingly crisp feeling and resilience, and had a texture very close to that of a genuine hemp woven fabric. Moreover, the washing durability of the texture was also very excellent.

Example 3 A denim knitted cloth (60S / 2 of 100% cotton) cut out after scouring was padded with a 20 g / liter sodium hydroxide solution and squeezed with a mangle to pick up 75%.
It was dried. Then, using a lab pin tenter, 170
After performing a dry heat treatment at ℃ for 1 minute, it was washed thoroughly with water with a soaper to complete the pretreatment.

Then, the pre-treated cloth was treated with a laboratory mercerizing frame to remove sodium hydroxide 15 at high temperature (85 ° C.).
% Zinc oxide 0.3% in the solution obtained,
Mercerize for 1 minute at -6 ℃,
Completed the main processing. The woven fabric obtained by the method of the present invention thus obtained was provided with a surprisingly crisp feeling and resilience, and had a texture very close to that of a genuine hemp woven fabric. Moreover, the washing durability of the texture was also very excellent.

Example 4 A denim knit (60S / 2 of 100% cotton) cut out after scouring was padded with a 20 g / liter sodium hydroxide solution and squeezed with a mangle to pick up 75%.
It was dried. Then, using a lab pin tenter, 170
After performing a dry heat treatment at ℃ for 1 minute, it was washed thoroughly with water with a soaper to complete the pretreatment.

Next, to this pre-treated cloth, sodium hydroxide 1 at high temperature (85 ° C.) was used by using a laboratory mercerizing frame.
Dissolve 0.3% zinc oxide in a 5% solution, then add 10% urea.
% In a solution obtained by dissolving 1% at a low temperature of -6 ° C.
This process was completed by performing a mercerization process for a minute. The woven fabric obtained by the method of the present invention thus obtained was provided with a surprisingly crisp feeling and resilience, and had a texture very close to that of a genuine hemp woven fabric. Moreover, the washing durability of the texture was also very excellent.

[0032]

INDUSTRIAL APPLICABILITY In the present invention, alkali treatment as pretreatment-
This is a combination of the steps of dry heat treatment and then treatment with an alkaline solution containing sodium zincate. By configuring in this way, it is possible to improve the texture of cellulose fibers to a texture very similar to natural hemp. Moreover, the washing durability of the linen-like texture can be satisfied.

Claims (1)

[Claims] 1. A cellulosic fiber characterized in that the cellulosic fiber is impregnated with an alkaline solution, then subjected to a dry heat treatment, and then the fiber is subjected to a low temperature mercerization treatment using an alkaline solution containing sodium zincate. Pseudo processing method.