JPH0813251A - Production of alginic acid-based filament - Google Patents

Abstract

PURPOSE:To efficiently obtain an alginic acid-based filament preferably used for nonwoven fabrics, woven fabrics and fabric products and free from mutual binding of fibers. CONSTITUTION:An aqueous solution of a water-soluble alginic acid salt is extruded into a bath of an aqueous solution of a divalent metal salt to spin the alginic acid salt and the resultant fiber bundle is washed with water, and (1) water in the fiber bundle is replaced with an organic solvent and then the fiber bundle is dried or (2) the fiber bundle is spread and warm air kept to <=80 deg.C is blown to the fiber bundle and the fiber bundle is dried to produce the objective alginic acid-based filament.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved method for producing alginic acid-based filaments. More specifically, the present invention, for the production of alginic acid-based long fibers used for non-woven fabrics, woven fabrics, and textile products, a drying treatment is performed to prevent binding of the fibers to each other, and the alginic acid-based long fibers suitable for the above-mentioned uses are produced. The present invention relates to a method for efficiently producing

[0002]

2. Description of the Related Art Calcium alginate fibers can be obtained by extruding a water-soluble aqueous solution of alginate into an aqueous solution containing calcium ions to prevent it (Japanese Patent Laid-Open No. 61-174499, British Patent No. 1394741).
, U.S. Pat. No. 4,421,583), and the use of this calcium alginate fiber, for example, in medical dressings and paper.

When a medical or paper product is made in water, a method of defibrating and disintegrating in water after cutting damp fibers as it is (JP-A-61-174499) or damp For example, a method (US Pat. No. 4,421,583) in which a fiber bundle is suction-dewatered and partially dehydrated to be further dried with a heat cylinder is used.

However, in the dry state, non-woven fabrics, woven fabrics,
When manufacturing cloth products, self-adhesion occurs due to hydrogen bonding between the hydroxyl groups and carboxyl groups of alginic acid-based filaments (1990 Annual Meeting of the Textile Society of Japan S-49), and the fiber bundle contains water. If the fiber is dried while containing it, it will be bound, and it will not be suitable as a fiber for non-woven fabrics, woven fabrics, and textile products that require defibrated fibers. Therefore, it is not preferable to adopt the above method. Further, even when a nonwoven fabric is produced in a wet state, it is desired that the fiber material in a good dispersed state is used when the fiber raw material after storage is used.

[0005]

Under these circumstances, the present invention prevents binding of fibers to each other in dehydration and drying treatment, and is used for non-woven fabrics, woven fabrics, and fabric products. The purpose of the present invention is to provide a method for efficiently producing

[0006]

Means for Solving the Problems As a result of intensive studies for achieving the above-mentioned object, the present inventors have found that in order to prevent the binding of fibers to each other, the fiber bundle is dried in a state of embracing water. Focusing on what should not be done, in the dehydration drying process,
By substituting water with a hydrophilic organic solvent, or by defibrating the fiber bundle after washing with water and blowing hot air, it is possible to dry without binding the fibers to each other, and achieve that purpose. Based on this finding, the present invention has been completed.

That is, according to the present invention, a water-soluble alginate aqueous solution is extruded into a bath of a divalent metal salt aqueous solution and spun,
After washing the obtained fiber bundle with water, (1) the water in the fiber bundle is replaced with a hydrophilic organic solvent and then dried, or (2) the fiber bundle is defibrated and the temperature is adjusted to 80 ° C or lower. The present invention provides a method for producing an alginic acid-based long fiber, which is characterized by blowing hot air and drying.

In the method of the present invention, first, a water-soluble alginate aqueous solution is extruded into a bath of a divalent metal salt aqueous solution and spun. As the water-soluble alginate, for example, sodium alginate, potassium alginate, ammonium alginate and the like are preferable. These may be used alone or in combination of two or more. Further, the content of these water-soluble alginates in the aqueous solution is usually in the range of 1 to 10% by weight from the viewpoint of easiness of spinning.

On the other hand, preferable examples of the divalent metal salt include calcium salt, barium salt, nickel salt and cobalt salt. These divalent metal salts may be used alone or in combination of two or more. The content of these divalent metal salts in the aqueous solution is
It is usually selected in the range of 1 to 20% by weight.

For the spinning, the water-soluble alginate aqueous solution is extruded into a bath of the divalent metal salt aqueous solution from a nozzle having a large number of holes having a pore size of 0.01 to 0.30 mm, and the obtained fiber bundle is rolled. It is done by winding it up. The temperature during spinning is not particularly limited, but spinning is usually performed at room temperature.

The fiber bundle thus spun is thoroughly washed with water and then dried. This drying treatment needs to be performed so that the fibers are not bound together. In the present invention, (1) a method of substituting water in the fiber bundle with a hydrophilic organic solvent and then drying, or (2) A method is used in which the fiber bundle is defibrated, and hot air of 80 ° C. or lower is blown onto it to dry it.

Examples of the hydrophilic organic solvent used in the method (1) include alcohols having 1 to 5 carbon atoms,
Examples include ketones having 2 to 5 carbon atoms and esters having 2 to 5 carbon atoms. Examples of alcohols having 1 to 5 carbon atoms include methanol, ethanol, n-propanol, and isopropanol, and examples of ketones having 2 to 5 carbon atoms include acetone and methyl ethyl ketone, for example, esters of 2 to 5 Examples thereof include methyl acetate and methyl formate. These organic solvents may be used alone or in combination of two or more.

In the method using the organic solvent, the fiber bundle after being washed with water is sequentially passed through a plurality of stages, for example, two to three stages of organic solvent baths, so that the water content in the fiber bundle becomes a hydrophilic organic solvent. After the replacement, the organic solvent attached to the fiber bundle is removed by drying. The organic solvent used is 95% or more. Further, the drying for removing the attached organic solvent may be carried out in a dryer, may be sucked and dried in the process of rolling, or may be air-dried.

On the other hand, in the method (2) of blowing hot air, the fiber bundle after washing with water is disintegrated and hot air of 80 ° C. or lower is left in the state where the central portion of the fiber bundle remains wet. Blow not to. In this case, it is advantageous to use the multi-stage spraying method. The temperature of the warm air is preferably as low as possible in the range of room temperature to 80 ° C., but it is preferable to select it appropriately in relation to the number of stages. Also, in the washing step, the fiber bundle (usually a nozzle having several hundred to several thousand holes is used during spinning, so it is transported in the washing bath in a bundle) on the back side of the roll. In addition, it is advantageous that the cleaning effect is improved and the binding is prevented by defibrating as wide as possible.

The alginic acid-based long fibers thus obtained are long fibers composed of calcium alginate, barium alginate, nickel alginate, cobalt alginate, or a mixture thereof, which are not bound to each other and are non-woven fabrics or woven fabrics. Suitable for use in fabric products.

[0016]

According to the method of the present invention, alginic acid-based long fibers can be efficiently produced from water-soluble alginate, and by applying a special drying treatment, the fibers are prevented from binding and evenly unwound. Since a fine fiber is obtained, it can be suitably used for non-woven fabrics, woven fabrics, and fabric products.
In addition, since the non-woven fabric, woven fabric, and fabric product obtained from the alginic acid-based long fibers can be easily imparted with functionality, new product development is possible.

[0017]

The present invention will be described in more detail by way of examples, which should not be construed as limiting the invention thereto.

Example 1 Sodium alginate (Grade I-7F, manufactured by Kimitsu Chemical Industry Co., Ltd., viscosity of a 1% by weight aqueous solution at 750 mPa · s at 20 ° C.) was added to ion-exchanged water, and after stirring with high viscosity,
Agglomerates were removed by filtration using a 300-mesh nylon net to prepare a 5 wt% sodium alginate aqueous solution.

This sodium alginate aqueous solution was used in a laboratory wet spinning device (manufactured by Toho Kakoki Construction Co., Ltd.)
In a 5 wt% calcium chloride aqueous solution coagulating bath at 0 ° C., 2 atm from a nozzle (hole diameter 0.10 mm, number of holes 1000), 1
It was extruded at a speed of 7 g / min and wound at a speed of 11 m / min to prepare a calcium alginate long fiber bundle. Then, it was transferred to a cleaning bath containing ion-converted water for cleaning. For washing, use three water washing baths arranged in series, and use three baths of calcium alginate fiber bundle with a roll width of 8
It was expanded so that it was worth the cost.

Next, while being transferred between the rolls having a length of 120 cm and a total length of 240 cm, a warm air of 80 ° C. was applied to four household hair dryers so as to hit at right angles from a position 30 cm away from the fiber bundle. Used and sprayed. The properties of the calcium alginate fiber bundle thus obtained are shown in Table 1.

The fiber bundle was spread like a net, and the binding fibers were slightly recognized at both ends of the net. Further, the elongation of the fiber was about the same as the fiber obtained by drying the washed product by the conventional method, but the flexibility was slightly low.

Example 2 A calcium alginate fiber bundle was prepared in the same manner as in Example 1, then washed with water in the first water washing bath, and then treated with the following organic solvent.

That is, after the first water washing bath, the first methanol bath (99% methanol) and the second methanol bath (9
(9% methanol) was provided and the calcium alginate fiber bundle was sequentially transferred to the first water washing bath, the first methanol bath and the second methanol bath. The fiber bundle leaving the second methanol bath is
Air was blown from a distance of 30 cm with a home fan to evaporate the solvent and produce a calcium alginate fiber bundle. The properties of this product are shown in Table 1. This fiber bundle was disintegrated into a single fiber, and the elongation was also greatly improved.

Example 3 In Example 2, 99.
A calcium alginate fiber bundle was produced in the same manner as in Example 2 except that 5% ethanol was used. The properties of this product are shown in Table 1.

This fiber bundle is disintegrated into a single fiber,
Although the strength was slightly lower than that of Example 2, the elongation was about the same, and the strength and the elongation were values suitable for the production of the nonwoven fabric.

[0026]

[Table 1]

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hideki Kobiga 2-3-3 Hananomiya-cho, Takamatsu City, Kagawa Prefectural Institute of Industrial Technology Shikoku Institute of Industrial Technology

Claims (9)

[Claims] 1. A water-soluble alginate aqueous solution is extruded into a bath of a divalent metal salt aqueous solution and spun, the resulting fiber bundle is washed with water, and then the water in the fiber bundle is replaced with a hydrophilic organic solvent,
Then, a method for producing an alginic acid-based filament is characterized by drying. 2. The hydrophilic organic solvent is at least one selected from alcohols having 1 to 5 carbon atoms, ketones having 2 to 5 carbon atoms, and esters having 2 to 5 carbon atoms. 1. The method for producing an alginic acid-based filament according to 1. 3. The method for producing an alginic acid-based filament according to claim 2, wherein the alcohol having 1 to 5 carbon atoms is methanol, ethanol, n-propanol or isopropanol. 4. The method for producing an alginic acid-based filament according to claim 2, wherein the ketone having 2 to 5 carbon atoms is acetone or methyl ethyl ketone. 5. The method for producing an alginic acid-based continuous fiber according to claim 2, wherein the ester having 2 to 5 carbon atoms is methyl acetate or methyl formate. 6. A water-soluble alginate aqueous solution is extruded into a bath of a divalent metal salt aqueous solution and spun, and the obtained fiber bundle is washed with water and then defibrated, and hot air at 80 ° C. or lower is blown onto it. A method for producing an alginic acid-based long fiber, which comprises: 7. The method for producing alginic acid-based long fibers according to claim 1, wherein the water-soluble alginate is sodium alginate, potassium alginate, ammonium alginate or a mixture thereof. 8. The method for producing alginic acid-based long fibers according to claim 1, wherein the aqueous solution of a divalent metal salt is an aqueous solution containing a calcium salt, a barium salt, a nickel salt, a cobalt salt or a mixture thereof. 9. The method for producing an alginic acid-based continuous fiber according to claim 1, wherein the alginic acid-based continuous fiber comprises calcium alginate, barium alginate, nickel alginate, cobalt alginate or a mixture thereof.