JPH04119121A - Production of fiber of natural polysaccharides - Google Patents

Abstract

PURPOSE:To obtain the subject fiber, excellent in elongation and softness without surface stickiness and useful in the medical, clothes and food fields by spinning an aqueous solution composed of natural water-soluble polysaccharides, a polyhydric alcohol and water into a coagulation bath containing the polyhydric alcohol and removing the excess water. CONSTITUTION:An aqueous solution composed of natural water-soluble polysaccharides [e.g. alginic acid (salt), furcellaran, carrageenan or agar], a polyhydric alcohol (e.g. sorbitol, ethylene glycol or glycerol) and water is spun into a coagulation bath containing the polyhydric alcohol to remove the excess water. Thereby, the objective fiber is obtained.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to the production of natural polysaccharide fibers.

[Prior art and problems to be solved] Polysaccharides molded into fibers include a method of obtaining chitin fibers by wet spinning a chitin dope prepared by dissolving it in a solvent such as chitin dope dichloroacetic acid, and then drawing it. , a method is known in which dry fibers are obtained by wet-spinning an aqueous alginic acid solution into a solution of metal ions that can form water-insoluble alginates.

In order to adjust the strength and elongation of the fibers obtained by these methods, or to impart texture, appearance, feel, etc., acidic polysaccharides and water-soluble proteins may be added to the extent that spinnability is not prevented, or the temperature of the coagulation bath may be adjusted. , a method of changing the time spent in the bath is known.

Natural polysaccharides have functions such as edibility, water absorption, and water solubility, and by forming them into fibers, they can be used as water absorbing materials such as gauze in the medical and clothing fields, blood absorbing materials, and processing aids in the food field. It is expected that it will be used.

However, in order to improve the properties of chitin fibers and alginate fibers that have been developed so far without preventing their spinnability, acidic multi-11! However, the elongation required when processing these fibers cannot be obtained using the methods of adding soluble proteins and water-soluble proteins.

[Means for Solving the Problems] Therefore, the present inventors investigated a method for obtaining natural polysaccharide fibers with high elongation and flexibility from a completely different perspective from the conventional techniques, and as a result, the present invention was completed. The gist is that after spinning natural water-soluble polysaccharides, polyhydric alcohols, and water into a coagulation bath that mainly contains a filtrate solution and polyhydric alcohols, excess water is removed. It is in the manufacturing method of natural polysaccharide fiber.

The natural polysaccharide fiber obtained by the method of the present invention is made by adding polyhydric alcohol to a coagulation bath, and the conventional method uses a coagulation bath with a single composition of an aqueous inorganic ion solution or a water-miscible organic solvent. Natural poly 11 made! [It can be made to exhibit flexible fiber physical properties with an elongation 1.3 to 4 times higher than the elongation of the fiber.

Examples of natural polymers II used in the present invention include alginic acid and its salts, furcellulan, carrageenan, agar, pectin, xanthan gum, tamarind, gum arabic, arabinogalactan, gellan gum, etc.
Examples of the polyhydric alcohol include sorbitol, ethylene glycol, propylene glycol, polyethylene glycol, and glycerin.

The above-mentioned polyhydric alcohol has the effect of imparting elongation to the polysaccharide fibers of the present invention, and is present in the polyIi! The ratio of polyhydric alcohol to polyhydric alcohol is preferably in the range of 1:2 to 1:0.1. Adding polyhydric alcohol at a rate higher than this range results in polyhydric alcohol! At the same time, after spinning the spinning dope and drying, the surface of the fiber becomes sticky and difficult to handle. Furthermore, fibers made from a stock solution containing polyhydric alcohol in a proportion below this range lack elongation and flexibility.

The coagulation bath used in the present invention mainly contains polyhydric alcohol and water, and further contains acetone, ethanol, methanol,
It can be prepared by adding a water-miscible organic solvent such as isopropyl alcohol, mineral oil, vegetable oil, liquid paraffin, etc., or a combination of a water-miscible organic solvent and/or mineral oil, vegetable oil, liquid paraffin, etc. and polyhydric alcohol. Mixing ratio is 10/1
It is preferable to use a method of adding a polyhydric alcohol to a water-miscible organic solvent, etc., within a range of an amount of 173 to 173%. It is preferable to use the same type as the one used.

When carrying out the present invention, carrageenan is used as the natural polysaccharide, a potassium chloride aqueous solution is preferably used, and when sodium alginate or LM pectin is used, a calcium chloride aqueous solution is preferably used.

In addition, when the coagulation bath is not only a single-stage coagulation bath but also a multi-stage coagulation bath, a coagulation bath of a water-miscible organic solvent, a coagulation bath of an aqueous inorganic ion solution, etc. can be sequentially used. Since it is necessary to reduce the load of water removal, it is necessary to mix polyhydric alcohol in the same ratio in these baths.

To carry out the present invention, a spinning stock solution prepared by the above-described preparation method is quantitatively spun into a coagulation bath containing a polyhydric alcohol through a nozzle having a fixed pore size to form a fibrous gel. Furthermore, if necessary, after passing through a coagulation bath with a preliminary dehydration function, the fibers are dried to obtain natural polysaccharide fibers.

The water content in the resulting fibrous gel is preferably 20% or less; a fibrous gel with a high water content will cause the fibers to weld together, making it difficult to unravel.

The present invention will be explained in more detail with reference to Examples below.

Example 1 This was heated to 85°C and dissolved for 60 minutes to obtain a spinning stock solution. Next, this spinning stock solution was vacuum defoamed (-0.5kg
/c1fl), then use a gear pump to
17.2 m from a nozzle with 10 holes of 0 u / /
It was discharged into the coagulation bath at a rate of 11 lin.

The coagulation bath used at this time was an aqueous solution of 1% MCI and 6.9% glycerin. After the formed fibrous gel was allowed to stay in the coagulation bath for 2.5 seconds, it was pre-rolled at a speed of 57 m/sin. The moisture content of the resulting fibers was 88% on a dry basis.

This fibrous material was further mixed with 80% isobrobyl alcohol and 6
．． After staying in the second coagulation bath consisting of an aqueous solution containing 9% glycerin for 5 seconds to perform coagulation and dehydration, the coagulation liquid adhering to the fiber surface was removed by wind pressure and warm air at 40°C to 80°C was applied stepwise. Drying was performed to obtain dry carrageenan fibers with a water content of 20% or less.

Example 2 The fibrous gel with a water content of 88% obtained in Example 1 was kept in a coagulation bath of 80% isopropyl alcohol and 4.6% glycerin aqueous solution for 5 seconds, and coagulated and dehydrated in the same manner as in Example 1. to obtain dry carrageenan fibers.

Example 3 The fibrous gel with a water content of 88% produced in Example 2 was reduced to 80%
The fibers were allowed to stay in a coagulation bath consisting of an aqueous solution containing isopropyl alcohol and 2.3% glycerin for 5 seconds to coagulate and dehydrate, and then dried in the same manner as in Example 1 to obtain dry carrageenan fibers.

Comparative Example The gel fiber with a water content of 88% produced in Example 1 was 80%
The fibers were allowed to stay in an aqueous isopropyl alcohol solution for 5 seconds, coagulated and dehydrated, and dried in the same manner as in Example 1 to obtain dry carrageenan fibers.

Table 1 shows the results of measuring the elongation of the fibers obtained as described above.

Table 1 As is clear from Table 1, the fibers obtained by adding glycerin to the coagulation bath as in Examples 1 to 3 are different from the fibers obtained using a coagulation bath without glycerin as in Comparative Example. We were able to obtain natural polysaccharide fibers that were larger and more flexible than those produced by conventional methods.

[Effects of the Invention] In order to ensure the elongation of the dry fiber obtained according to the method of the present invention, it is not necessary to add an excessive amount of polyhydric alcohol to the spinning dope as in the prior art. It can be made with a non-sticky surface and has increased elongation and flexibility, leading to expanded applicability in the medical, clothing, and food fields.

Patent applicant: Mitsubishi Rayon Co., Ltd.

Claims (1)

[Claims] A method for producing natural polysaccharide fibers, which comprises spinning an aqueous solution consisting of a natural water-soluble polysaccharide, a polyhydric alcohol, and water in a coagulation bath containing a polyhydric alcohol, and removing excess water.