JPH0123591B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides improvements in a method for modifying cellulose fibers,
In particular, it relates to a method for obtaining cellulosic fibers with improved hand. As a method to further improve these properties of cellulosic fibers, which are superior to other fibers in terms of hygroscopicity and texture, a method has been proposed in which cellulosic fibers are treated for a short period of time with an aqueous solution containing cellulase. (Special Publication No. 52-48236). This method is said to give cellulose fibers appropriate hygroscopicity and a supple texture, while also suppressing a decrease in strength. However, according to the results of the follow-up experiments conducted by the present inventors, short-time treatment as shown in the example is insufficient to improve the texture, and long-term treatment improves the texture but reduces the strength. It decreased significantly. The present invention aims to improve the above method,
It is characterized in that, prior to the cellulase treatment, it is treated with a fiber swelling agent as described below. This makes it possible to improve the feel of the fibers without significantly reducing strength. That is, the present invention relates to a method for modifying cellulose fibers, which comprises pretreating the cellulose fibers using an aqueous swelling agent solution when the fibers are treated with an aqueous solution containing cellulase. The swelling agent used in the present invention has the ability to dissolve cellulose fibers, and suitable examples include sulfuric acid, phosphoric acid, zinc chloride, sodium hydroxide, etc. In addition, metal hydroxides such as potassium hydroxide, Inorganic salts such as rhodan salts, amine-metal compounds such as copper ethylene diamine, etc. can also be used. Such a swelling agent may be used as an aqueous solution at an appropriate concentration depending on the type of fiber to be treated and the purpose of use.
Aqueous solutions of 75% sulfuric acid, 78-86% phosphoric acid, and 60-75% zinc chloride are commonly used, and for rayon, 5-25% aqueous sodium hydroxide solutions are used. In general, rayon, Tetoron/rayon, and cotton/rayon lose weight faster than cotton, so the swelling agent treatment conditions are slightly weaker than for cotton. The temperature and time of pretreatment using a swelling agent depend on the type and concentration of the swelling agent, the type of fiber to be treated, etc., and are not particularly limited, but are usually 5 to 50 minutes.
Do this at 30℃ for 1 to 30 seconds. Generally, if the pretreatment temperature is too high or the pretreatment time is too long, the fibers will become more brittle. After washing the pretreated cellulose fibers with water,
When subjected to the next cellulase treatment, if an acid or alkali is used as a swelling agent, it is preferable to neutralize it with an appropriate neutralizing agent. Pretreated fibers are usually subjected to cellulase treatment while still wet. Cellulases used in the present invention include cellulosin AC-8 and AC-15 (commercial product from Ueda Chemical Co., Ltd., bacterial cell; Aspergillus genus);
Cellulase A3 (commercial product from Amano Pharmaceutical Co., Ltd., bacterial cells; Aspergillus genus), Cellulosin T [commercial product from Ueda Chemical Co., Ltd., bacterial cells: Trichoderma genus],
Cellulase T-AP4 (commercial product from Amano Pharmaceutical Co., Ltd., bacterial cells;
Examples include Trichoderma genus), Onozuka 3S (commercial product from Kinki Yakult Co., Ltd., bacterial cells; Trichoderma genus), and Meiselase (commercial product from Meiji Pharmaceutical Co., Ltd., bacterial cells; Trichoderma genus). Such cellulase is usually prepared as a 0.1 to 2.0% aqueous solution, and the pH is adjusted to 3.0 to 6.0 using acetic acid, acetate, etc. to prepare a cellulase treatment solution. The temperature of the cellulase treatment solution is usually selected within the range of 40 to 50°C. If the treatment temperature is too high, the enzyme activity will decrease more quickly. Further, the treatment time in the cellulase treatment depends on the cellulase concentration of the treatment solution, the pH, the treatment temperature, the type of fiber to be treated, etc., and is usually 2 to 24 hours, although it is not limited. If the treatment time is too long, the strength of the fibers will be significantly reduced. The cellulose fibers treated with the cellulase treatment solution are washed with water, dehydrated, and subjected to post-treatment. Post-treatment is 0.1-0.3% caustic soda and sodium thiosulfate
10~ using an aqueous solution containing 0.3~0.7% (40~60℃)
This process involves soaking for 30 minutes, washing with water, dehydrating, and drying. The weight loss rate and tensile strength retention rate of cellulose fibers treated as described above are usually 8.
~20% and 50 to 70%, the texture becomes smooth and supple with a unique flexibility that cannot be obtained by conventional methods. The cellulosic fibers treated by the method of the present invention may be in any form, but a woven form is particularly preferred. The method of the present invention can impart the same weight loss effect (the larger the weight loss rate is, the softer it becomes) to cellulose fibers with a shorter cellulase treatment time than the method using only cellulase treatment. The strength loss of the resulting cellulosic fibers is smaller than that of cellulose fibers with the same weight loss rate obtained by cellulase treatment alone. The modified cellulose fiber obtained by the method of the present invention has good hygroscopicity, moderate strength, and unique texture, so it can be widely used as a material for underwear, innerwear, medical supplies, etc. Hereinafter, the present invention will be explained with reference to Examples. Example 1 65% 100% cotton twill fabric (3/1 basis weight 360g/m ² )
It was immersed in a sulfuric acid solution (20°C) for 5 seconds, washed with water, neutralized with a 1% aqueous solution of sodium carbonate, washed with water, and then squeezed. The squeezed cotton twill fabric was soaked in a 1% cellulase water bath (cellulase; cellulosin T; bath ratio: 1:
30, pH: 4.2, bath temperature: 45°C) and treated for 8 hours while circulating the liquid. The cotton twill fabric thus treated was washed with water, dehydrated, then immersed in an aqueous solution (50°C) containing 0.2% caustic soda and 0.5% sodium thiosulfate for 30 minutes, washed with water, dehydrated, and dried. Table 1 shows the weight loss rate, tensile strength retention rate, and properties of the cotton twill fabric obtained by the above treatment. Example 2 A cotton twill fabric was treated in the same manner as in Example 1, except that the treatment time in the cellulase water bath was changed to 5.6 hours, and its properties are shown in Table 1. Example 3 A cotton twill fabric was immersed for 30 seconds in a 72.5% zinc chloride aqueous solution (20°C) instead of a 65% sulfuric acid solution,
After washing with water, the sample was squeezed, and the subsequent treatment was carried out in accordance with the procedure of Example 1. Table 1 shows the properties of the obtained cotton twill fabric. Example 4 A cotton twill fabric was treated in the same manner as in Example 3 except that the treatment time in the cellulase water bath was changed to 9 hours,
Its properties are shown in Table-1. Comparative Example 1 Example 1 except that the pretreatment using sulfuric acid was omitted.
The cotton twill fabric was treated in the same manner as above, and its properties were expressed.
Shown in 1. Comparative Example 2 A cotton twill fabric was treated in the same manner as in Comparative Example 2, except that the treatment time in the cellulase water bath was changed to 17.5 hours, and its properties are shown in Table 1. Example 5 Example 1 except that the immersion time in the sulfuric acid solution was 8 seconds and the immersion time in the cellulase water bath was 7 hours.
Tetoron/cotton (hereinafter referred to as T/C) (30/70) mixed plain fabric was treated in the same manner as above, and its properties were expressed.
Shown in 1. Comparative Example 3 Example 5 except that the pretreatment using sulfuric acid was omitted
Treat T/C (30/70) mixed plain fabric in the same manner as above,
Its properties are shown in Table-1. Example 6 Instead of 1% cellulosin T as cellulase
A cotton twill fabric was treated in the same manner as in Example 1, except that 1.2% meicelase was used and the treatment time in the cellulase water bath was 7.2 hours, and its properties are shown in Table 1.
Shown below. Comparative Example 4 A cotton twill fabric was treated in the same manner as in Example 6, except that the pretreatment using sulfuric acid was omitted and the treatment time in the cellulase water bath was changed to 22 hours, and its properties are shown in Table 1. 【table】

Claims (1)

[Scope of Claims] 1. A method for modifying cellulose fibers, which comprises pretreating the fibers using an aqueous inorganic swelling agent solution that can dissolve the fibers when the fibers are treated with an aqueous solution containing cellulase. . 2. The method according to item 1, wherein the swelling agent is sulfuric acid, phosphoric acid, zinc chloride or sodium hydroxide.