JP2853921B2 - New cellulose copper solution and manufacturing method. - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cellulose copper solution and a method for producing cellulose fibers, nonwoven fabrics or hollow fibers for medical use, which are used in clothing or industrial fields. A new and useful low copper low ammonia cellulose copper solution is provided in these fields.

[0002]

2. Description of the Related Art Cellulose is a naturally occurring material,
It is widely used in the form of wood, paper, cotton, hemp, etc. It has been known that cellulose is dissolved in an ammonia solution of copper hydroxide since the middle of the 19th century, and artificial fibers and the like are produced by spinning and coagulating and regenerating cellulose from this cellulose copper ammonium solution. Regarding this technology, for example, Textile Handbook Raw Material Edition (edited by The Textile Society of Japan, Maruzen, 1968)
Details are described on pages 495 to 510 and the like.

[0003]

A conventional copper copper ammonium solution contains copper in a molar ratio of 1.0 or more to a pyranose ring with respect to cellulose, and ammonia of 5% or more with respect to the solution. This is described, for example, in Textile Handbook, Raw Material Section 503. If the amount of copper or ammonia is less than this amount, a sufficient amount of cellulose will not be dissolved in the copper copper solution, and it will not be possible to make a cellulose copper copper solution having sufficient spinnability. This is, for example, by Hess et al.
Z.Phys.Chem., A145, paragraphs 401 to 450, etc.

[0004] Since copper cellulose ammonium solution is usually used under conditions of neutralization with an acid to regenerate cellulose, copper and ammonia contained in the solution are converted to salts such as copper sulfate and ammonium sulfate in the regenerating solution. Remains. At this time, since the concentration of copper and ammonia in the cellulose copper solution is high as described above, the concentration of salts in the regenerating solution also increases as a result, and some of the salts precipitate as crystals and adhere to the device, and the There is a phenomenon that the cellulose fibers and the like that have been damaged are damaged, which causes a problem that productivity is deteriorated. To solve this problem, many attempts have been made to improve the composition of the regenerating solution, the flow rate of the solution, the production equipment, and the like. As a drastic improvement method of this problem, it has been required to reduce the amounts of copper and ammonia in a solution of copper cellulose cellulose.

[0005] In order to deal with environmental problems that have been increasing in recent years, many efforts have been made in the field of the regenerated cellulose industry to reduce the amount of chemical substances discharged into the environment. Reducing the amount of copper and ammonia in the solution directly leads to a reduction in the amount of waste liquid, which helps to reduce the amount discharged into the environment. . Further, the reduction in the amount of copper and ammonia used also leads to a reduction in the production cost of regenerated cellulose fibers.
However, a cellulose copper ammonium solution satisfying the above requirements has not been known.

SUMMARY OF THE INVENTION An object of the present invention is to provide a solution of copper cellulose ammonium solution having a low content of copper and ammonia and a method for producing the solution by solving the problems of the conventionally known copper copper solution.

[0007]

DISCLOSURE OF THE INVENTION The present inventors have conducted studies with the aim of reducing the amounts of copper and ammonia in this cellulose copper acetate solution. As mentioned above, copper is dissolved in aqueous ammonia in advance to make a copper-copper solution, and cellulose is added to this to make a cellulose copper-copper solution with a lower ratio of copper and ammonia than before. Is insufficient in solubility, and the desired amounts of copper and ammonia are reduced, and a spinnable cellulose copper solution cannot be produced. Therefore, the present inventors changed the order of mixing the raw materials, firstly adsorbed copper to cellulose, recovered it in a solid state, and then tried to make a solution of cellulose copper solution in the order of dissolving it in ammonia water. Surprisingly, even when a smaller ratio of copper and ammonia is used, cellulose adsorbing copper shows extremely high solubility in aqueous ammonia, and the content of copper and ammonia is lower than before. The present invention has been found to give a cellulose copper solution which is as low as possible and has sufficient spinnability, thereby completing the present invention.

That is, the copper cellulose ammonium solution according to the present invention contains copper in such an amount that the molar ratio of cellulose to pyranose rings is from 0.3 to 0.7, and more than 3% of the solution. Cellulose and 0.5% to 5%
% Ammonia and 0.25% to 1% alkali metal hydroxide. At this time, it is preferable to use lithium hydroxide, sodium hydroxide or potassium hydroxide as the alkali metal hydroxide.

The method of the present invention for producing a copper-ammonium cellulose solution is characterized in that a cellulose on which copper is adsorbed is first prepared, and then this is dissolved in an aqueous solution containing ammonia. The cellulose having copper adsorbed thereon can be obtained by the following various methods, but is not limited to these methods. Cellulose is immersed in a copper-copper solution containing 0.5 mol / l or more of alkali metal hydroxide, and then the undissolved solids are pressed and collected, and the dried or undried solids adsorb copper as it is Method for use as a modified cellulose. A method in which cellulose is immersed in a solution of copper and then dried as it is, as a cellulose to which copper is adsorbed. A method in which cellulose is immersed in an aqueous solution of copper hydroxide and an alkali metal hydroxide, and the undissolved solid content is pressed and recovered, and the resultant is used as the cellulose on which copper is adsorbed.

It is preferable to use lithium hydroxide, sodium hydroxide or potassium hydroxide as the alkali metal hydroxide used in producing cellulose adsorbing copper. Hereinafter, the present invention will be described in detail. In obtaining cellulose adsorbed with copper by the above-described method, adding an alkali metal hydroxide to the copper copper solution prevents separation of the cellulose into the copper copper solution to separate the solid copper-adsorbed cellulose from the solution. To get it. The temperature at the time of adsorption is not particularly limited, but is preferably −5 ° C. or higher in order to prevent icing of the solution.
It is preferably 0 ° C. or lower. Further, the temperature is more preferably 5 ° C. or higher from the viewpoint of the copper adsorption rate, and more preferably 40 ° C. or lower from the viewpoint of the difficulty of the hydrolysis reaction of cellulose. The adsorption time may be 5 minutes or more, but if the adsorption is performed for a longer time, problems such as a decrease in the degree of polymerization of cellulose do not occur. Is more preferable because it becomes uniform. The charge ratio at the time of adsorption of cellulose and copper can be freely selected, but at the time of dissolution of the copper-adsorbed cellulose in a later step, copper having a molar ratio of 0.3 or more is adsorbed on the pyranose ring of cellulose. Therefore, it is necessary to select in advance the charging ratio at the time of adsorption of cellulose and copper so that more copper is adsorbed. Regardless of the amount of copper adsorbed on the pyranose ring of cellulose, no matter how much copper is used, it is saturated at a molar ratio of about 0.7 and does not adsorb at a higher ratio. There is no limitation on the concentrations of copper and ammonia in the copper ammonium solution used for the adsorption, and a copper ammonia solution can be used as a dilute solution of copper ammonia water as long as copper is partially dissolved in the ammonia water. From the viewpoint of the adsorption device, it is more preferable that copper has a concentration of 0.02 mol / l or more and ammonia has a concentration of 1.2 mol / l or more. The alkali metal hydroxide used in the present invention may be any one. For example, lithium hydroxide, sodium hydroxide, potassium hydroxide and the like can be used alone or in combination of two or more.

The cellulose used in the present invention may be any cellulose, for example, cotton, cotton linter, hemp,
Natural cellulose, such as hardwood pulp and softwood pulp, and waste from the purification of these products can be used. It is more preferable to use regenerated cellulose such as viscose rayon yarn or cupra ammonium rayon yarn, or pulp or cotton linter that has been hydrolyzed to lower the degree of polymerization, because the solubility of copper-adsorbed cellulose is further improved. The solid of the copper-adsorbed cellulose thus obtained is taken out of the copper-copper solution, and the adhering copper-copper solution is removed by pressing. At this time, as long as the weight is less than 5 times the weight of the cellulose on which the copper is adsorbed, the copper ammonium solution may adhere to the solid of the copper-adsorbed cellulose. As a result, the copper copper solution adheres to the copper-adsorbed cellulose and partially remains as a result.As a result, the alkali metal hydroxide contained in the copper copper solution also partially adheres to the copper-adsorbed cellulose and is brought to the subsequent step, and finally, This is not a problem since the alkali metal hydroxide is also contained in the existing cellulose copper acetate solution, although it is partially contained in the cellulose copper acetate solution. It is described, for example, in the Textile Handbook, Raw Material, Item 502, line 23, etc. that the existing copper copper salt solution contains the alkali metal hydroxide free, not as a salt.

As described below, the copper-adsorbed cellulose is dissolved in an aqueous solution containing aqueous ammonia. From the viewpoint of the solubility of the copper-adsorbed cellulose in aqueous ammonia, the amount of the alkali metal hydroxide attached to the copper-adsorbed cellulose was determined by dissolving the copper-adsorbed cellulose in aqueous ammonia to make a cellulose copper solution. Preferably, the amount is in the range of 0.25% to 1% of the total solution. The copper-adsorbed cellulose is not sufficiently dissolved in aqueous ammonia even if the amount of the alkali metal hydroxide is larger or smaller than the above range. When the amount of the alkali metal hydroxide attached to the copper-adsorbed cellulose is too small, a necessary amount of the alkali metal hydroxide can be previously added to the ammonia water. When the amount of the alkali metal hydroxide attached to the cellulose adsorbed on the copper is too large, a necessary amount of acid is added in advance to the ammonia water to partially neutralize the alkali metal hydroxide to form a salt of the cellulose copper solution as a salt. You can leave it inside. Further, when the amount of the alkali metal hydroxide attached to the copper-adsorbed cellulose is too large, the copper-adsorbed cellulose is dried and washed with water, etc., and only the alkali metal hydroxide is washed out without desorbing the copper to reduce the amount. It can also be adjusted. The obtained copper-adsorbed cellulose is directly or dried to remove most of ammonia and water, and then dissolved in aqueous ammonia to prepare a cellulose copper solution. At the time of drying, the water content can be reduced by washing with methanol, ethanol, acetone or the like in advance. The drying apparatus may be any apparatus, for example, a convection oven, an infrared oven, or the like. The drying temperature is preferably 70 ° C. or less in order to prevent copper hydroxide from being dehydrated into copper oxide. However, if a measure such as shortening the drying time by using a forced circulation type oven is taken, the drying temperature is not necessarily limited. Not.

In addition to the above-mentioned method, the copper-adsorbed cellulose can be obtained by immersing the cellulose shown in the following in a copper solution and then directly drying it without pressing. In this case, the copper copper solution does not need to contain the alkali metal hydroxide, but the swelling of the cellulose, the partial dissolution or the like may hinder the drying of the copper-adsorbed cellulose,
It is more preferable to use an ammonium copper solution containing an alkali metal hydroxide at a concentration of mol / l or more. The charge ratio at the time of adsorption of cellulose and copper can be freely selected, but at the time of dissolution of the copper-adsorbed cellulose in a later step, copper having a molar ratio of 0.3 or more is adsorbed on the pyranose ring of cellulose. It is necessary to use an amount of copper solution so that more copper is adsorbed. The conditions for immersing cellulose in a copper solution are the same as in the case of performing the above-mentioned pressing. Drying is performed under the same conditions as in the above-described compression, but washing with methanol or the like before drying is not performed.

In addition to the above methods and, the copper-adsorbed cellulose can also be obtained by immersing the cellulose in an aqueous solution of copper hydroxide and an alkali metal hydroxide and pressing and recovering the solid content. At this time, the charge ratio at the time of adsorption of cellulose and copper can be freely selected, but when dissolving the copper-adsorbed cellulose in a later step, copper having a molar ratio of 0.3 or more with respect to the pyranose ring of cellulose is used. Since it is necessary to adsorb, a larger amount of copper hydroxide is used. The concentration of the alkali metal hydroxide in the aqueous solution may be any concentration as long as the copper hydroxide dissolves at least partially, but from the viewpoint of the amount of dissolved copper and the rate of adsorption of copper to cellulose. It is preferably at least 10%, more preferably from 15% to 30% in order to prevent a decrease in the degree of polymerization of cellulose. The temperature at the time of immersion is not limited, but from the viewpoint of prevention of reduction in the degree of polymerization of cellulose and the rate of adsorption of copper,
More preferably, it is in the range of 0 ° C to 25 ° C. The obtained copper-adsorbed cellulose is used for dissolution after washing and drying, if necessary, as in the case of immersion in the above-mentioned copper ammonium solution.

The concentration of ammonia in the ammonia water in which the copper-adsorbed cellulose is dissolved can be selected so that the concentration of ammonia in the dissolved cellulose copper solution is in the range of 0.5% to 5%. The temperature at the time of dissolution is not particularly limited, but is −5 ° C. for the same reason as the temperature at the time of adsorption.
It is preferably at least 50 ° C and at most 5 ° C and 40 ° C
It is more preferred that: The apparatus used for dissolution is not limited, and any apparatus can be used as long as it can effectively stir a high-viscosity cellulose copper solution. The dissolution operation is preferably performed immediately after the mixing of the copper-adsorbed cellulose and the aqueous ammonia. It is not preferable to leave the copper-adsorbed cellulose and the aqueous ammonia for a long time without stirring after mixing, since this involves hydrolysis of the cellulose. After the dissolution, if necessary, a part of the remaining solid content is removed by filtration using a wire mesh, a filter cloth, or the like to obtain a cellulose copper ammonium solution. The resulting copper acetate cellulose solution contains less copper and ammonia than any previously known cellulose copper acetate solution, providing a useful new tool for the regenerated cellulose industry.

[0016]

It is presumed that when cellulose is dissolved in the copper solution, the copper complex ions react with the cellulose molecules to dissolve the cellulose molecules while destroying the solid structure such as hydrogen bonds. The reaction of the copper complex ion to the cellulose molecule is an equilibrium reaction, and the higher the concentration of the copper complex ion near the cellulose molecule, the more the solid structure of the cellulose is destroyed, and the more the cellulose is dissolved. However, since the concentration of copper in the solution of copper has a limit in terms of solubility, as long as the method of dissolving cellulose in the solution of copper is used, the concentration of copper complex ions in the vicinity of cellulose molecules should be It cannot be much higher than the process. In the method of the present invention, copper is first adsorbed on solid cellulose at a high concentration by a method such as using a copper copper solution containing an alkali metal hydroxide. Can be caused to act on cellulose molecules, and upon dissolution, the solid structure of the cellulose molecules is strongly destroyed, so that the solubility of the cellulose is improved. As a result, copper copper having a low copper and ammonia concentration which has not been realized so far has been achieved. It is presumed that cellulose could be dissolved in the solution as a result.

[0017]

EXAMPLES Examples of the present invention will be described below, but the present invention is not limited to these examples. As the cellulose used in the examples, cotton was used as absorbent cotton according to the Japanese Pharmacopoeia Law. Cotton linters imported from the United States were treated by Asahi Kasei Kogyo Co., Ltd. in a 3.5% aqueous sodium hydroxide solution at 172 ° C. for 90 minutes, then bleached with 270 ppm of chlorine at 25 ° C. for 45 minutes, and washed with alkaline water. Washed with water and dried. As the softwood pulp, Alaska pulp from the United States was used. Hardwood pulp used was Rio Grande, Brazil. As the regenerated cellulose, a regenerated cellulose nonwoven fabric Bemliese manufactured by Asahi Kasei Kogyo Co., Ltd. was used. As the pulp acid hydrolyzate, a product of Alaska Pulp Co., Ltd. was immersed in 25% sulfuric acid at 60 ° C. for 2 hours, washed with water, and dried. As the regenerated cellulose acid hydrolyzate, a product obtained by immersing benlyse in 25% sulfuric acid at 60 ° C. for 8 minutes, washing with water, and drying was used.

In the examples, the molar ratio of copper to the pyranose ring of cellulose was determined by neutralizing and acidifying a cellulose copper solution with 1N hydrochloric acid, and then separating and drying the precipitated cellulose by filtration and weighing to determine the pyranose ring. Determine the number of moles, then precipitate the copper in the filtrate as copper sulfide using hydrogen sulfide, filter, dry and weigh to determine the number of moles of copper, and divide the number of moles of copper by the number of moles of pyranose ring I asked for it. Hereinafter this is referred to as the copper / cellulose ratio. In addition, a value obtained by dividing the weight of the cellulose precipitated here by the weight of the copper copper solution used for neutralization is referred to as the cellulose concentration of the copper copper solution and expressed in%.

In the examples, the ammonia concentration in the cellulose copper ammonium solution was calculated from the amount of ammonia contained in the ammonia water used for dissolving the cellulose on which the copper was adsorbed. However, when the cellulose on which copper is adsorbed is used for dissolution without drying, the weight of cellulose and the weight of copper as copper hydroxide are subtracted from the total weight of the copper adsorbed cellulose and the adsorbed copper solution. Is the weight of the solution containing the same concentration of ammonia as the adsorption liquid, and the amount of ammonia contained therein was added to the amount of ammonia contained in the aqueous ammonia used for dissolution.

In the examples, the concentration of the alkali metal hydroxide in the cellulose copper ammonium solution is determined by neutralizing and titrating the dried copper-adsorbed cellulose with dilute sulfuric acid to thereby remove the alkali metal contained in the copper-adsorbed cellulose. The amount of hydroxide was determined, and the concentration of the alkali metal hydroxide in the cellulose copper ammonium solution was calculated from this value. When an acid was added to the system for the purpose of neutralizing the alkali metal hydroxide, the calculation was performed excluding the amount of the alkali metal hydroxide corresponding to the number of moles of the acid. If the cellulose adsorbed copper is used without drying, the same amount of alkali metal hydroxide as the content of alkali metal hydroxide in the cellulose adsorbed copper dried after adsorption under the same conditions is considered to be included. The concentration of the alkali metal hydroxide in the cellulose copper solution was determined.

In the examples, the viscosity was measured at 25 ° C. using a B-type viscometer (BM type manufactured by Tokyo Keiki). The centrifugation was performed at 10,000 rpm for 40 minutes using a CR20B2 type centrifuge manufactured by Hitachi, Ltd. Example 1 Copper hydroxide 0.055 mol / l, ammonia 2.4 mol /
Then, 18.0 g of cellulose (regenerated cellulose acid hydrolyzate) was added at 25 ° C. to 1.43 liter of a copper ammonium solution containing 1 mol / l and 0.6 mol / l of sodium hydroxide, and the mixture was immersed for 1 hour. Then, the cellulose (wet) on which the copper was adsorbed was filtered off from the solution on a glass filter, and squeezed while sucking to remove the adhering solution as much as possible. At this time, the total weight of the cellulose (wet) on which the copper containing the adhering solution was adsorbed was 85 g. This is designated as BH-1-1. B
Take 63 g of H-1-1, wash twice with 150 ml of methanol, spread it on filter paper, and put
12. Drying for hours, cellulose adsorbing copper (dry)
2 g were obtained. The alkali metal hydroxide content measured by neutralization titration was 10.2%. This is called BH-1-
Let it be 2. Take 16 g of BH-1-2 and 100
After washing with methanol, the mixture was washed with 150 ml of methanol and dried in an oven at 50 ° C. for 1 hour to obtain 14.9 g of copper-adsorbed cellulose (after washing with water). The alkali metal hydroxide content determined by neutralization titration was 5.1%. This is designated as BH-1-3. 7.5 g of BH-1-3
In a 00 ml separable flask, 42.5 g of 3% aqueous ammonia was added at 15 ° C. and stirred, and after centrifugation, the supernatant was isolated through a 400-mesh stainless steel wire gauze to obtain a cellulose copper ammonium solution. Obtained. The cellulose concentration in this solution was 9.1%. The copper / cellulose ratio in this solution was 0.52. The ammonia concentration in this solution was 2.55%. The concentration of the alkali metal hydroxide in this solution was 0.765%.
The viscosity of this solution was 120 poise. Put this solution in B
H-1-3-S.

Example 2 Regenerated cellulose was used as cellulose, and 84 g of cellulose (wet) on which copper was adsorbed was prepared in the same manner as in the preparation of BH-1-1 in Example 1, except that adsorption was performed at 15 ° C. for 2 hours. Obtained. This is designated as BL-1-1. BL-1-1 1
1.8 g is put in a 100 ml separable flask, and 5
38.2 g of 3% aqueous ammonia was added at 0 ° C., and the mixture was stirred. Subsequently, after centrifugation, the supernatant was isolated through a 400-mesh stainless steel wire mesh to obtain a cellulose copper ammonium solution. The cellulose concentration in this solution was 4.5%. The copper / cellulose ratio in this solution was 0.50. The ammonia concentration in this solution was 2.97%. The concentration of the alkali metal hydroxide in this solution was 0.7
7%. The viscosity of this solution was 35 poise.
This solution is designated as BL-1-1-S.

Example 3 BL-1-1 was used as cellulose (wet) adsorbing copper.
20. Cellulose adsorbed with copper in the same manner as in the preparation of BH-1-2 in Example 1 except that 62 g was used (dry)
8 g were obtained. The alkali metal hydroxide content measured by neutralization titration was 9.9%. This is BL-1-2
And 3.9 g of BL-1-2 was placed in a 100 ml separable flask, and 3% ammonia water 4 was added at 30 ° C.
Add 6.1 g and stir, then centrifuge and discard supernatant
Isolation through a 00 mesh stainless steel wire mesh gave a cellulose copper ammonium solution. The cellulose concentration in this solution was 4.5%. The copper / cellulose ratio in this solution was 0.50. The ammonia concentration in this solution was 2.77%. The concentration of the alkali metal hydroxide in this solution was 0.77%. The viscosity of this solution was 30 poise. This solution is designated as BL-1-2-S.

Examples 4 to 7 Except for changing the type of cellulose, a cellulose-adsorbed cellulose (wet) was prepared in the same manner as in Example 2, and a cellulose copper solution was obtained in the same manner as in Example 3. Type of cellulose used (abbreviated as A), copper-adsorbed cellulose (wet)
(Unit g, abbreviated as B) and the amount used in the next step (unit g, abbreviated as C), yield of cellulose adsorbed copper (dry) (unit g, abbreviated as D), alkali metal hydroxide The content (%, abbreviated as E), the amount (unit g, abbreviated as F) used in the next dissolution step, and the amount of aqueous ammonia (unit g, abbreviated as G) used for dissolution are shown in Table 1. Solution viscosity (poise, abbreviated as H), copper / cellulose ratio (abbreviated as J), cellulose concentration (%, abbreviated as K), ammonia concentration (%, abbreviated as L), alkali metal Table 2 shows the hydroxide concentration (%, abbreviated as M) and the name of the solution.

[0025]

[Table 1]

[0026]

[Table 2]

Examples 8 to 12 and Comparative Example 1 Using BH-1-3, a cellulose copper ammonium solution was prepared in the same manner as in Example 1 except that the ammonia concentration used was changed. The copper / cellulose ratio in these solutions was 0.52. The concentration of the alkali metal hydroxide in these solutions was 0.765%. Table 3 shows the ammonia concentration (%) of the used ammonia water, the cellulose concentration (%), the ammonia concentration (%), and the solution viscosity (poise) in the obtained cellulose copper acetate solution. Comparative Example 1
In the case, cellulose adsorbed with copper (after washing with water) was not sufficiently dissolved in aqueous ammonia.

[0028]

[Table 3]

Examples 13 to 15 and Comparative Examples 2 to 4 Copper-adsorbed cellulose (wet) was prepared in the same manner as in Example 1 except that pulp acid hydrolyzate was used as cellulose and adsorption was performed at 30 ° C. for 8 hours. Had made. Using all of this, the cellulose adsorbed copper (dry) 2 in the same manner as in Example 1.
8.3 g were obtained. The alkali metal hydroxide content measured by neutralization titration was 9.5%. This is AH-1
-2. 3.5 g of aqueous sulfuric acid solutions of various concentrations were added to 40 g of 3% aqueous ammonia, and AH-1-2.
5 g was dissolved in the same manner as in Example 1 to obtain a cellulose copper ammonium solution. The ammonia concentration in these solutions was 2.4
%Met. The copper / cellulose ratio in these solutions was 0.1.
51. Table 4 shows the concentration (%) of the aqueous sulfuric acid solution, the concentration (%) of the cellulose in the copper cellulose ammonium solution, the concentration (%) of the alkali metal hydroxide, and the solution viscosity (poise).
In Comparative Example 2, the cellulose on which copper was adsorbed hardly dissolved in aqueous ammonia.

[0030]

[Table 4]

Examples 16 to 19 and Comparative Example 5 Copper-adsorbed cellulose (wet) was prepared in the same manner as in Example 1 except that the weight of cellulose was changed variously. These were all dried in the same manner as in Example 1 and then washed with water to obtain cellulose adsorbed with copper (after washing with water). Table 5 shows the weight (g) of the cellulose used initially, the yield (g) of the obtained cellulose on which copper was adsorbed (after washing), and the alkali metal hydroxide content (%). Using the cellulose adsorbed with copper (after washing with water), a cellulose copper solution was obtained in the same manner as in Example 1. The ammonia concentration in these cellulose copper ammonium solutions was 2.55%. Table 6 shows the cellulose concentration (%), the copper / cellulose ratio, the alkali metal hydroxide concentration (%), and the solution viscosity (poise) of the obtained cellulose copper ammonium solution.

[0032]

[Table 5]

[0033]

[Table 6]

Examples 20 to 22 Copper-adsorbed cellulose (wet) in the same manner as in Example 1 except that a solution having the composition shown in Table 7 was used as a copper-copper solution.
Was prepared, and the whole amount was used to prepare a cellulose-adsorbed cellulose (dry) in the same manner as in Example 1. Using the whole amount, a cellulose-adsorbed cellulose was obtained in the same manner as in Example 1 (after washing with water).
I got Table 7 shows the content (%) of the alkali metal hydroxide measured by the neutralization titration method. Using these cellulose adsorbed with copper (after washing with water), a cellulose copper solution was obtained in the same manner as in Example 1. The ammonia concentration in these cellulose copper ammonium solutions was 2.55%. Table 8 shows the cellulose concentration (%), the copper / cellulose ratio, the alkali metal hydroxide concentration (%), and the solution viscosity (poise) of the obtained cellulose copper ammonium solution.

[0035]

[Table 7]

[0036]

[Table 8]

Example 23 In the same manner as in Example 2 except that potassium hydroxide having the same concentration was used instead of sodium hydroxide, 88 g of cellulose (wet) having copper adsorbed thereon was obtained. Using 12.4 g of this, it was dissolved in 37.6 g of aqueous ammonia in the same manner as in Example 2 to obtain a cellulose copper ammonium solution. The cellulose concentration in this solution was 4.5%. The copper / cellulose ratio in this solution was 0.51. The ammonia concentration in this solution was 2.95%. The concentration of the alkali metal hydroxide in this solution was 0.96%. The viscosity of this solution was 37 poise.

Example 25 In the same manner as in Example 2 except that lithium hydroxide having the same concentration was used instead of sodium hydroxide, 80 g of cellulose (wet) on which copper was adsorbed was obtained. Using 11.2 g of this, it was dissolved in 38.8 g of aqueous ammonia in the same manner as in Example 2 to obtain a cellulose copper ammonium solution. The cellulose concentration in this solution was 4.4%. The copper / cellulose ratio in this solution was 0.51. The ammonia concentration in this solution was 2.95%. The concentration of the alkali metal hydroxide in this solution was 0.68%. The viscosity of this solution was 32 poise.

Example 26 Copper hydroxide 0.232 mol / l, ammonia 10.5 mol
18.0 g of cellulose (regenerated cellulose acid hydrolyzate) was added to 224 ml of a copper ammonium solution containing 1 mol / l and 0.6 mol / l sodium hydroxide at 25 ° C., and the mixture was immersed for 1 hour. Then spread this on a glass petri dish and set it at 50 ° C.
After drying in an oven for 6 hours, 32.8 g of cellulose adsorbed with copper (dry) was obtained. The alkali metal hydroxide content determined by neutralization titration was 17.9%.
This was washed with 1 liter of water at 5 ° C., then with 250 ml of methanol, and dried in an oven at 50 ° C. for 1 hour to give 24.9.
g of cellulose adsorbed with copper (after washing with water) was obtained. The alkali metal hydroxide content measured by the neutralization titration method is 4.
8%. Take 7.5 g of this and place in a 100 ml separable flask,
Add 2.5 g and stir, then centrifuge and remove supernatant
Isolation through a 00 mesh stainless steel wire mesh gave a cellulose copper ammonium solution. The cellulose concentration in this solution was 8.9%. The copper / cellulose ratio in this solution was 0.52. The ammonia concentration in this solution was 2.55%. The concentration of the alkali metal hydroxide in this solution was 0.72%. The viscosity of this solution was 105 poise.

Example 27 8.3 g of copper hydroxide was added to a 20% aqueous sodium hydroxide solution 20
Suspended in 0 ml. At this time, the copper hydroxide partially dissolves in the aqueous sodium hydroxide solution to form a deep blue color. 18.0 g of cellulose (regenerated cellulose acid hydrolyzate)
Was added at 10 ° C. and immersed for 1 hour. Thereby, the cellulose is colored blue. Then, the cellulose (wet) on which the copper was adsorbed was filtered off from the solution on a glass filter, and squeezed while sucking to remove the adhering solution as much as possible. At this time, the total weight of the cellulose (wet) on which the copper containing the adhering solution was adsorbed was 90 g. The whole was taken, washed twice with 150 ml of methanol, spread on a filter paper, and dried in an oven at 50 ° C. for 1.5 hours to obtain 29.8 g of cellulose (dry) on which copper was adsorbed. The whole was taken, washed with 400 ml of water at 5 ° C., washed with 150 ml of methanol, and dried in an oven at 50 ° C. for 1 hour to obtain 126.4 g of cellulose adsorbed with copper (after washing with water). The alkali metal hydroxide content determined by neutralization titration was 6.7%. Take 7.5 g of this in a 100 ml separable flask,
42.5 g of aqueous ammonia was added thereto, followed by stirring. After centrifugation, the supernatant was isolated through a 400-mesh stainless steel wire mesh to obtain a cellulose copper ammonium solution.
The cellulose concentration in this solution was 7.9%. The copper / cellulose ratio in this solution was 0.45. The ammonia concentration in this solution was 2.55%. The concentration of the alkali metal hydroxide in this solution was 1.0%.
The viscosity of this solution was 58 poise.

Reference Example 1 Cellulose copper ammonium solution (BH-1-3) prepared in Example 1
-S) Using 100 g, spinning was performed using 35 ° C. warm water as a coagulation bath using a flow tube having a draw ratio of 7 times, then regenerated in 1 L of a 3% sulfuric acid bath, washed with water and dried to obtain regenerated cellulose fibers. Obtained. The regenerated cellulose fiber obtained was 12
It was 0 denier, the strength was 2.5 g / denier, and the elongation was 14%. Ammonia contained in the warm water of the coagulation bath after spinning was 0.1 mol in total. The sulfuric acid bath after spinning was closed and left at 25 ° C. for 14 days, but no crystals were precipitated.

Comparative Example 6 A regenerated cellulose fiber was obtained in the same manner as in Reference Example 1, except that 100 g of a cellulose copper acetate solution (manufactured by Asahi Kasei Bemberg Plant), which is currently used industrially, was used. The cellulose concentration in the cellulose copper solution was 9.2%. The copper / cellulose ratio in this solution was 1.00. The ammonia concentration in this solution was 6.85%. The concentration of the alkali metal hydroxide in this solution was 0.3%. The viscosity of this solution was 250 poise. The obtained regenerated cellulose fiber had a denier of 110, a strength of 2.4 g / denier and an elongation of 15%. Ammonia contained in the warm water of the coagulation bath after spinning was 0.3 mol in total. When the sulfuric acid bath after spinning was closed and allowed to stand at 25 ° C., white and pale green crystals were precipitated after 2 days.

Reference Example 2 Cellulose copper ammonium solution (BL-1-2) prepared in Example 3
Using -S), regenerated cellulose fibers were obtained by spinning, regenerating, washing with water and drying using 1N hydrochloric acid as a coagulation bath. The resulting regenerated cellulose fiber had a denier of 90, a strength of 1.2 g / denier and an elongation of 5%.

Reference Examples 3 to 6 Spinning was carried out in the same manner as in Reference Example 2 using the cellulose copper solutions obtained in Examples 4 to 7, to obtain regenerated cellulose fibers. Table 9 shows the name of the solution, the thickness of the fiber (denier), the strength of the fiber (g / denier), and the elongation (%) of the fiber.

[0045]

[Table 9]

[0046]

Industrial Applicability According to the present invention, the content of copper and ammonia in a cellulose copper ammonium solution used for producing cellulose fibers, nonwoven fabrics or hollow fibers for medical use used in the field of clothing or industrial use is dramatically increased. It is useful for directly reducing the amount of chemical substances such as copper and ammonia discharged to the environment as waste liquid in the field of the regenerated cellulose industry. In addition, since the copper copper acetate solution is usually used under conditions of neutralization with an acid to regenerate cellulose, the use of the copper copper acetate solution of the present invention also results in a lower concentration of salts in the regenerating solution, resulting in a decrease in the concentration of salts. This is preferable because the portion does not precipitate as crystals and adheres to the device, and does not damage the regenerated cellulose fibers or the like to lower the productivity. Further, the reduction in the amount of copper and ammonia used leads to a reduction in the production cost of regenerated cellulose fibers, and is also useful from this point.

Claims (2)

(57) [Claims] 1. The method according to claim 1, wherein the molar ratio of the pyranose ring to the cellulose is from 0.3 to 0.7.
Ammonia in the range of 5% to 5% and 0.25% to 1%
A cellulose copper ammonium solution comprising an alkali metal hydroxide in the range of: 2. First, a cellulose on which copper is adsorbed is prepared.
Next, a method for producing a cellulose copper ammonium solution, comprising dissolving the same in an aqueous solution containing ammonia.