JPH0791690B2 - Sterilized recycled cellulose fiber - Google Patents

Description

TECHNICAL FIELD The present invention relates to bactericidal regenerated cellulose fibers. More specifically, it relates to a fiber material having excellent bactericidal properties and hygroscopicity.

[Conventional technology]

The bactericidal activity of copper against microorganisms is already well known. For example, there is a method in which a sock woven with copper wires or a copper sulfate aqueous solution is added to water in an aquarium to prevent the generation of green algae.

However, metallic copper such as copper wire and copper plate, when moist, produces a patina that is highly toxic to the human body. Further, when an aqueous solution of copper sulfate, copper nitrate, copper formate, copper salicylate, etc. is used, these water-soluble copper salts are toxic to the human body and therefore are considerably restricted in use.

In view of the above-mentioned drawbacks, as a result of earnest research on a method for producing a sterilizing fiber that is harmless to the human body and does not lose sterilization property for a long period of time, a method of adsorbing a copper compound insoluble in water to the fiber is disclosed in JP-A-54 Although disclosed in JP-A-160900, copper oxide or copper hydroxide is adsorbed on the regenerated cellulose fiber by these methods, the copper compound is distributed on the surface of the regenerated cellulose fiber, and the copper compound peels off due to abrasion or the like. There is a drawback to
Further, in the methods disclosed in JP-A-56-169808 and JP-B-57-56581, copper sulfide is distributed on the fiber surface, and like the above-mentioned method, the copper compound is peeled off due to abrasion or the like.

[Problems to be solved by the invention]

The present inventors have examined the method of maintaining the sterilization property for a long period of time without peeling the copper compound from the fiber surface, and as a result of containing a water-insoluble copper compound inside the fiber, The inventors have found that the drawbacks can be sufficiently satisfied, and have completed the present invention.

That is, the object of the present invention is to contain a copper compound insoluble in water even in the inside of the yarn cross section so that the copper compound does not easily peel off and fall off, and is stable and has excellent bactericidal properties and bactericidal properties that maintain bactericidal properties for long periods A regenerated cellulose fiber is provided.

[Means for solving problems]

That is, at least one copper compound selected from copper hydroxide, copper oxide, and copper sulfide is used in the radial direction from the center of the fiber to 90
%, A bactericidal copper ammonia cellulose fiber having a copper content of 200 mg or more per 1 g of the fiber, which is evenly distributed within the fiber cross section.

The mode of containing the copper compound in the fiber cross section in the present invention is not limited, but an example of the distribution state is that in the yarn cross section direction, the copper compound is distributed substantially uniformly within 90% of the radius from the center of the yarn in the radial direction. Let it be included. Another example of the distribution state is the radial direction from the center of the yarn cross section in the radial direction.
The ring-shaped copper compound is distributed and contained in the range of 20% to 90%.

The distribution of the copper compound in the yarn cross-sectional direction can be controlled by the following method.

For example, a copper ammonia cellulose solution is spun and coagulated with warm water at 20 ° C to 50 ° C. The yarn is a yarn containing a coordination compound of copper and cellulose (hereinafter referred to as blue yarn).

The surface of the blue thread is regenerated with acid to distribute the coordination compound of copper and cellulose within 90% of the radial direction from the center of the thread.

The blue yarn obtained by the above-mentioned method is copper ammonia cellulose fiber containing copper hydroxide. In the case of copper oxide, it can be obtained by immersing the blue thread in hot water. If necessary, the treatment can be performed in an aqueous hydrogen peroxide solution.

Copper ammonia cellulose fiber containing copper sulfide is a sulfurizing agent for blue yarn in which the surface of blue yarn is regenerated with acid and the coordination compound of copper and cellulose is distributed within 90% of the radial direction from the center of the yarn. As a result, copper sulfide can be distributed almost uniformly within 90% of the radial direction from the center of the yarn when treated with a solution containing sodium sulfide. Further, when the blue yarn whose surface has been regenerated with an acid is treated with a solution containing potassium sulfide as a sulfuric acid agent, copper sulfide can be distributed in a ring shape within 20% to 90% in the radial direction.

Although the content of the copper compound contained in the copper ammonia cellulose fiber of the present invention can be freely controlled, it is necessary to contain 200 mg or more in terms of copper oxide per 1 g of cellulose fiber in order to obtain stable bactericidal property for a long period of time. is there. If it is more than 350 mg, the physical properties of yarn tend to be deteriorated.

This is that the copper ammonia cellulose fiber containing the copper compound is hardly released even when immersed in water, but the amount of the copper compound sufficient to have bactericidal properties is in water, and a very small amount of copper oxide equivalent 0.1 PPM or more. Is sufficient, and the elution amount from the fiber into water at 20 ° C. is 0.1 to 0.2 PPM. Also, 1g of cellulose
If it contains 200 mg or more in terms of copper oxide, the amount of elution after immersion in water at 20 ° C. for 1 month is 0.1 to 0.2 PPM, and it has sufficient bactericidal properties. The content of the copper compound according to the present invention can be controlled by the pickling conditions when the surface of the blue yarn is regenerated with an acid. For example, the treatment time (acid bath passage time) is 1/1000 second to 1 second with an aqueous solution having a sulfuric acid concentration of 0.1% by weight to 3% by weight.

The bactericidal cuprammonium cellulose fiber according to the present invention is a trichophyton mentaglophyte (Tric
hophyton mentagrophytee, IFO 5466), Trichophyton rubrum, IFO 5467, Aspergillus flavus, IFO 634
3), Aspergillu niger, IFO
6341), Penicillium citriu
m, IFO 6252), Fusalium lini, IF
O 4468), Rhizopus nigrica
ns, IFO 5781), Cladosporium Regini
orium resinae, IFO 8588), Pseudomonas
nas), Staphylococcus aureus, and Escherichia coli, but it is not particularly limited to these bacteria.

〔Example〕

 Hereinafter, the present invention will be described in more detail with reference to Examples.

Example 1 A copper ammonia cellulose solution having a composition of a cellulose concentration of 10% by weight, an ammonia concentration of 7% by weight, and a copper concentration of 3.6% by weight, which was prepared by a known method, was spun from a spinneret having 45 holes of 0.5 mm in diameter. It was extruded into the filled spinning funnel at a discharge rate of 5.8 cc / min, and was sufficiently coagulated while being tensioned while flowing down in the funnel to obtain a matifilament of a coordination compound of copper and cellulose. The temperature and flow rate of the spinning water are 37 ℃,
The coagulated fiber was wound in the shape of a pellicle at a speed of 50 m / min at 300 c.c./min. The blue yarn thus obtained was regenerated by passing it through a 1.4% by weight sulfuric acid bath for 0.05 seconds to obtain a yarn containing a coordination compound of copper and cellulose within 90% of the yarn cross-section direction. Next, the yarn was washed with water and dried to obtain a bactericidal copper ammonia cellulose fiber containing copper hydroxide inside the regenerated cellulose fiber. The distribution of copper was measured by X-ray microanalyzer.

This fiber has a reduction rate against Staphylococcus aureus (Staphylococcus aureus) by the shake flask method.
95%, which shows excellent bactericidal properties. The amount of copper contained in the yarn was 230 mg in terms of copper oxide per 1 g of cellulose fiber.

Example 2 The copper ammonia cellulose fiber containing copper hydroxide obtained in the same manner as in Example 1 was passed through hot water at 80 ° C. to change the copper hydroxide contained in the fiber into copper oxide. 90% of copper oxide inside the ammonia cellulose fiber in the yarn cross-section direction
A sterilizing cuprammonium cellulose fiber contained within was obtained.

This fiber has a bacterial reduction rate against Staphylococcus aureus of 90% by the shake flask method and is excellent in bactericidal property. The amount of copper contained in the yarn was 208 mg in terms of copper oxide per 1 g of cellulose fiber.

Example 3 Regenerated cellulose fibers containing copper hydroxide obtained in the same manner as in Example 1 were immersed in an aqueous solution having a potassium sulfide concentration of 5% by weight and a temperature of 50 ° C. for 20 minutes, then washed with water and dried to form copper sulfide fibers. A sterilizing cuprammonium cellulose fiber contained inside was obtained.

In the fiber, copper sulfide is distributed in a ring shape in the yarn cross section direction at 20% or more and 90% or less of the radius.

The reduction ratio of this fiber to Staphylococcus aureus was 98% by the shake flask method, which shows excellent bactericidal properties. The amount of copper contained in the yarn was 210 mg in terms of copper oxide per 1 g of cellulose fiber.

Example 4 The bactericidal copper ammonia cellulose fibers obtained in Examples 1 to 3 were immersed in water at 20 ° C. for 1 month, and then dehydrated and dried. According to the flask method, the content of regenerated cellulose fibers containing copper hydroxide was 89%, the content of regenerated cellulose fibers containing copper oxide was 85%, and the content of regenerated cellulose fibers containing copper sulfide was 92%, all showing excellent bactericidal properties for a long period of time.

〔The invention's effect〕

The bactericidal copper ammonia cellulose fiber according to the present invention has excellent bactericidal properties, and also, since the copper compound is distributed inside the fiber, it has a synergistic effect with the regenerated cellulose fiber excellent in hygroscopicity and water absorption. It has excellent bactericidal properties for a long period of time.

The bactericidal copper ammonia cellulose fiber according to the present invention can be spun, woven and knitted, and can be mixed with various fiber materials depending on the application. Further, it is also possible to make a paper by mixing with a non-woven fabric or pulp, and make a film.

That is, the development of the fiber according to the present invention into the field of clothing or materials is extremely advantageous, and the application can be applied in a wide range. For example, in the field of clothing, sheets, diapers, socks, etc., and in the field of materials, drainage, filter media for use of sewage, and prevention of corrosion by microorganisms.

Claims (1)

[Claims] 1. At least one copper compound selected from copper hydroxide, copper oxide and copper sulfide is uniformly distributed within the fiber cross section within 90% of the radial direction from the center of the fiber, and copper A bactericidal copper ammonia cellulose fiber characterized in that the content is 200 mg or more in terms of copper oxide per 1 g of fiber.