JPH0525706A - New cellulose cuprammonium solution and production thereof - Google Patents

Abstract

PURPOSE:To obtain a new cellulose cuprammonium solution having low content of copper and ammonia by preparing cellulose having adsorbed copper and then dissolving the cellulose in an aqueous solution containing ammonia. CONSTITUTION:For example, cellulose is immersed in a cuprammonium solution containing an alkali metal hydroxide to prepare cellulose having adsorbed copper in an amount of 0.3-0.7 molar ratio to pyranose ring of cellulose. Then the cellulose is dissolved in an aqueous solution containing ammonia to give the objective cuprammonium solution containing >=3% cellulose, 0.5-5% ammonia and 0.25-1% alkali metal hydroxide.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cellulose copper ammonium solution used in the production of cellulose fibers, non-woven fabrics or cellulose hollow fibers used for medical use in the field of clothing or industry, and a method for producing the same. It is intended to provide a new and useful low copper-low ammonia ammonia-copper ammonium solution in these fields.

[0002]

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

[0003]

A conventional solution of copper-ammonium-containing cellulose contains copper in an amount of 1.0 or more in terms of molar ratio to cellulose and pyranose ring, and 5% or more of ammonia in the solution. This is described in, for example, Section 503 of Textile Handbook Raw Materials. If the amount of copper or ammonia is less than this amount, the cellulose will not dissolve in the copper ammonium solution in a sufficient amount, and a cellulose copper ammonium solution having sufficient spinnability cannot be prepared. This is for example
Z. Phys. Chem., A145, items 401-450.

Since a solution of ammonium copper-ammonium is usually used under the condition that it is neutralized with an acid to regenerate cellulose, copper and ammonia contained in the solution are converted into salts such as copper sulfate and ammonium sulfate in the regenerating solution. Remain in. At this time, since the concentration of copper and ammonia in the cellulose copper ammonium solution is high as described above, the concentration of salts in the regenerating solution also becomes high as a result, and a part of the salts precipitates as crystals and adheres to the device for regeneration. There is a phenomenon that the produced cellulose fiber or the like is damaged, which causes a problem that productivity is deteriorated. In order to solve this problem, many attempts have been made to improve the composition of the regenerating liquid, the flow rate of the liquid, and the manufacturing equipment. However, there has been a demand for reducing the amounts of copper and ammonia in a cellulose copper ammonium solution as a drastic improvement method for this problem.

Further, in order to deal with the 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 to the environment. Reducing the amount of copper and ammonia in the solution is directly linked to reducing the amount of waste liquid, and helps to reduce the amount discharged to the environment. From this point as well, a cellulose-copper ammonium solution with low copper and low ammonia was required. . Furthermore, the reduction in the amounts of copper and ammonia used leads to a reduction in the production cost of regenerated cellulose fibers.
However, there is no known cellulose copper ammonium solution that satisfies the above requirements.

An object of the present invention is to solve the problems of the conventionally known cellulose copper ammonium solution and to provide a cellulose copper ammonium solution having a low content of copper and ammonia, and a method for producing the solution.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted research for the purpose of reducing the amounts of copper and ammonia in this ammonium copper ammonium solution. As described above, copper is dissolved in ammonia water in advance to form a copper ammonium solution, and cellulose is added to the cellulose by a method in which the ratio of copper and ammonia is smaller than in the conventional method. Therefore, it is not possible to prepare a target solution of cellulose-copper ammonium having a low spin rate and a reduced amount of copper and ammonia and having spinnability. Therefore, the present inventors changed the order of mixing the raw materials, first tried adsorbing copper on cellulose to collect it in a solid state, and then dissolving it in ammonia water to make a solution of ammonium copper-ammonium solution. Surprisingly, even when using a smaller ratio of copper and ammonia than before, cellulose with copper adsorbed shows a very high solubility in ammonia water, and the content of copper and ammonia is higher than before. It has been found that a solution of ammonium copper ammonium having a low and sufficient spinnability is provided, and the present invention has been completed.

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

The method for producing a copper ammonium copper solution according to the present invention is characterized in that cellulose having copper adsorbed is first prepared and then 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 ammonium solution containing 0.5 mol / l or more of alkali metal hydroxide, then undissolved solids are squeezed and collected, and dried or undried solid is adsorbed on copper as it is. Method of using as the cellulose. A method in which cellulose is dipped in a copper ammonium solution, and then dried as it is to be used as copper-adsorbed cellulose. 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 squeezed and recovered to be used as the copper-adsorbed cellulose.

It is preferable to use lithium hydroxide, sodium hydroxide or potassium hydroxide as the alkali metal hydroxide used in the production of cellulose having copper adsorbed thereon. The present invention will be described in detail below. When obtaining the cellulose having copper adsorbed by the above-mentioned method, adding an alkali metal hydroxide to the copper ammonium solution prevents the dissolution of the cellulose in the copper ammonium solution and separates the solid state 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 freezing of the solution, and it is 5 from the viewpoint of reducing volatilization of ammonia.
It is preferably 0 ° C. or lower. Further, it is more preferably 5 ° C. or higher from the viewpoint of the adsorption rate of copper, and is more preferably 40 ° C. or lower from the viewpoint of difficulty in causing a hydrolysis reaction of cellulose. The adsorption time should be 5 minutes or more, but even if adsorption is performed for a longer time, problems such as a decrease in the degree of polymerization of cellulose do not occur. Therefore, if adsorption is performed from 30 minutes to 2 hours, the adsorption rate of copper Is more preferable because it is uniform. The charging ratio at the time of adsorption of cellulose and copper can be freely selected, but when the copper-adsorbed cellulose is dissolved in a later step, copper having a molar ratio of 0.3 or more is adsorbed to the pyranose ring of cellulose. Therefore, it is necessary to select in advance the ratio of cellulose and copper at the time of adsorption so that more copper is adsorbed. The ratio of copper adsorbed to the pyranose ring of cellulose is saturated at a molar ratio of about 0.7, no matter how much copper is used, and no more adsorbed. There is no limitation on the concentration of copper and ammonia in the copper ammonium solution used for adsorption, and if copper is partially dissolved in ammonia water, a dilute solution of copper in ammonia water can also be used. From the viewpoint of the adsorption device, it is more preferable that the concentration of copper is 0.02 mol / l or more and the concentration of ammonia is 1.2 mol / l or more. Any alkali metal hydroxide may be used in the present invention. For example, lithium hydroxide, sodium hydroxide, potassium hydroxide and the like can be used alone or in combination of two or more.

Any cellulose may be used in the present invention, such as cotton, cotton linter, hemp,
It is possible to use natural cellulose such as hardwood pulp and softwood pulp, and scraps obtained by refining these materials. Further, it is more preferable to use regenerated cellulose such as viscose rayon yarn and cupraammonium rayon yarn, pulp that is hydrolyzed to reduce the degree of polymerization, and cotton linter because the solubility of copper-adsorbed cellulose is further improved. The copper-adsorbed cellulose solid thus obtained is taken out of the copper ammonium solution, and the attached copper ammonium solution is removed by pressing. At this time, the copper ammonium solution may be attached to the solid of the copper-adsorbed cellulose as long as it is within 5 times the weight of the cellulose on which copper is adsorbed. In this way, the copper ammonium solution adheres to the copper-adsorbed cellulose and partially remains, so that the alkali metal hydroxide contained in the copper ammonium solution also partially adheres to the copper-adsorbed cellulose and is brought to the subsequent step, and finally, Although it will be partially contained in the cellulose-copper ammonium solution, this is not a problem because the alkali metal hydroxide is also contained in the existing cellulose-copper ammonium solution. It is described, for example, in Textbook Handbook, Raw Materials, Section 502, line 23 that the alkali metal hydroxide is contained as a salt in the existing cellulose copper ammonium solution, not as a salt.

As described later, 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 the ammonia water at that time, the amount of the alkali metal hydroxide attached to the copper-adsorbed cellulose is determined by dissolving the copper-adsorbed cellulose in the ammonia water to form a cellulose copper ammonium solution. Particularly, the amount is preferably in the range of 0.25% to 1% of the total solution. If the amount of alkali metal hydroxide is larger or smaller than the above range, the copper-adsorbed cellulose is not sufficiently dissolved in ammonia water. 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 added to the ammonia water in advance. When the amount of alkali metal hydroxide attached to copper-adsorbed cellulose is too large, a necessary amount of acid is added to ammonia water in advance to neutralize a part of the alkali metal hydroxide to form a cellulose copper ammonium solution as a salt. You can also leave it inside. Also, when the amount of alkali metal hydroxide attached to the copper-adsorbed cellulose is too large, the copper-adsorbed cellulose is dried and then washed with water or the like, and only the alkali metal hydroxide is washed out without desorbing copper to reduce the amount. It can also be adjusted. The obtained copper-adsorbed cellulose is directly or dried to remove most of the ammonia and water, and then dissolved in ammonia water to prepare a cellulose copper ammonium solution. During the drying, the water content can be lowered by washing with methanol, ethanol, acetone or the like in advance. Any drying device may be used, and for example, a convection type oven, an infrared oven or the like can be used. The drying temperature is preferably 70 ° C. or lower to prevent dehydration of copper hydroxide into copper oxide, but this is not always necessary if measures such as shortening the drying time by using a forced circulation oven are used. Not.

In addition to the above-mentioned method, the copper-adsorbed cellulose can be obtained by immersing the cellulose shown in 1 above in a copper ammonium solution and then directly drying it without pressing. In this case, it is not necessary for the copper ammonium solution to contain an alkali metal hydroxide, but the swelling and partial dissolution of the cellulose may hinder the drying of the copper-adsorbed cellulose.
It is more preferable to use a copper ammonium solution containing an alkali metal hydroxide at a concentration of mol / l or more. The charging ratio at the time of adsorption of cellulose and copper can be freely selected, but when the copper-adsorbed cellulose is dissolved in a later step, copper having a molar ratio of 0.3 or more is adsorbed to the pyranose ring of cellulose. Therefore, it is necessary to use copper ammonium solution in such an amount that more copper is adsorbed. The conditions for immersing the cellulose in the copper ammonium solution are the same as those for the above-mentioned pressing. Drying is performed under the same conditions as in the case of performing the pressing described above, but washing with methanol or the like before drying is not performed.

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 then squeezing and recovering the solid content thereof, in addition to the above methods. At this time, the charging ratio at the time of adsorption of cellulose and copper can be freely selected, but when the copper-adsorbed cellulose is dissolved in a later step, copper having a molar ratio of 0.3 or more to the pyranose ring of cellulose is selected. Since it is necessary to be adsorbed, 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 copper hydroxide is partially dissolved, but in terms of the amount of copper dissolved and the adsorption rate of copper to cellulose, It is preferably 10% or more, and more preferably 15% to 30% in order to prevent a decrease in the degree of polymerization of cellulose. Although there is no limitation on the temperature at the time of immersion, from the viewpoint of preventing the decrease in the degree of polymerization of cellulose and the adsorption rate of copper,
More preferably, it is in the range of 0 ° C to 25 ° C. The obtained copper-adsorbed cellulose is washed and dried, if necessary, as in the case of being immersed in the above copper ammonium solution, and then used for dissolution.

The concentration of ammonia in the ammonia water for dissolving the copper-adsorbed cellulose can be selected so that the concentration of ammonia in the ammonium copper-ammonium solution after dissolution is in the range of 0.5% to 5%. There is no particular limitation on the temperature at the time of melting, but -5 ° C for the same reason as the temperature at the time of adsorption.
It is preferably 50 ° C or higher and 50 ° C or higher and 40 ° C
The following is more preferable. The device used for dissolution is not limited, and any device can be used as long as it can effectively stir the high viscosity cellulose copper ammonium solution. The dissolving operation is preferably performed immediately after mixing the copper-adsorbed cellulose and the ammonia water. It is not preferable to mix the copper-adsorbed cellulose and the ammonia water without stirring for a long time because the cellulose is hydrolyzed. After the dissolution, if necessary, the partially dissolved solid content is removed by filtration using a wire net, a filter cloth or the like to obtain a cellulose copper ammonium solution. The obtained cellulose-copper ammonium solution contains less copper and ammonia than any of the known cellulose-copper ammonium solutions so far, and provides a useful new means for the regenerated cellulose industry.

[0016]

When the cellulose is dissolved in the copper ammonium solution, it is presumed that the copper ammonium complex ions react with the cellulose molecules and dissolve while destroying the solid structure such as hydrogen bonds of the cellulose molecules. The reaction of copper ammonium complex ion with the cellulose molecule is an equilibrium reaction, and the higher the concentration of copper ammonium complex ion in the vicinity of the cellulose molecule, the stronger the destruction of the solid structure of cellulose, and the more cellulose is dissolved. However, since the copper concentration in the copper ammonium solution has a limit in terms of solubility, as long as the method of dissolving cellulose in the copper ammonium solution is used, the copper complex ion concentration in the vicinity of the cellulose molecule is currently used. Can't be much higher than the process. In the method of the present invention, copper is first adsorbed at a high concentration on solid cellulose by a method such as using a copper ammonium solution containing an alkali metal hydroxide, whereby a high concentration of copper which is not practical in a copper ammonium solution is obtained. Can be made to act on the cellulose molecule, the solid structure of the cellulose molecule is strongly destroyed during dissolution, and the solubility of cellulose is improved, and as a result, copper copper with a low concentration of copper and ammonia, which has never 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 thereto. As the cellulose used in the examples, absorbent cotton compliant with Japanese Pharmacopoeia was used as cotton. As a cotton linter, what was imported from the United States was 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. It was washed with water and dried. The softwood pulp used was that of Alaska Pulp Company, USA. The hardwood pulp used was from Rio Grande, Brazil. As the regenerated cellulose, regenerated cellulose nonwoven fabric Benlyse manufactured by Asahi Kasei Corporation was used. The pulp acid hydrolyzate used was a product of Alaska Pulp Co., Ltd., which was immersed in 25% sulfuric acid at 60 ° C. for 2 hours, washed with water and dried. As the regenerated cellulose acid hydrolyzate, one 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 obtained by neutralizing and acidifying a cellulose copper ammonium solution with 1N hydrochloric acid, filtering and drying the precipitated cellulose, and weighing the pyranose ring. Calculate the number of moles, then precipitate the copper in the filtrate as copper sulfide with 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 the pyranose ring. I asked for it. Hereinafter, this is referred to as a copper / cellulose ratio. The weight of the precipitated cellulose is divided by the weight of the cellulose-copper ammonium solution used for neutralization, which is referred to as the cellulose concentration of the cellulose-copper ammonium solution, which is expressed in%.

In the examples, the ammonia concentration in the ammonium copper ammonium solution was calculated from the amount of ammonia contained in the ammonia water used to dissolve the cellulose adsorbed by copper. However, when the cellulose adsorbed with copper 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 cellulose adsorbed with copper and the copper ammonium solution adhering to it. Assuming that the weight is the weight of the solution containing the same concentration of ammonia as the adsorbent, the amount of ammonia contained therein was added to the amount of ammonia contained in the ammonia water used for dissolution.

In the examples, the concentration of the alkali metal hydroxide in the ammonium copper ammonium solution is determined by neutralizing the dried copper-adsorbed cellulose with dilute sulfuric acid to titrate the alkali metal contained in the copper-adsorbed cellulose. The amount of the 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 by removing the amount of alkali metal hydroxide corresponding to the number of moles of the acid. When the copper-adsorbed cellulose is used without drying, it is assumed that the same amount of alkali metal hydroxide as the content of alkali-metal hydroxide in the copper-adsorbed cellulose that has been adsorbed under the same conditions is dried. The concentration of the alkali metal hydroxide in the cellulose copper ammonium solution was determined.

In the examples, the viscosity was measured at 25 ° C. using a B type viscometer (BM type manufactured by Tokyo Keiki Co., Ltd.). The centrifugation was performed using a CR20B2 type centrifuge manufactured by Hitachi Ltd. at 10,000 rpm for 40 minutes. Example 1 0.055 mol / l copper hydroxide, 2.4 mol / ammonia
1 (10.8 g) of cellulose (regenerated cellulose acid hydrolyzate) was added to 1.43 l of a copper ammonium solution containing 1 and sodium hydroxide (0.6 mol / l) at 25 ° C., and the mixture was immersed for 1 hour as it was. Then, the cellulose-adsorbed cellulose (wet) was filtered off from the solution on a glass filter and squeezed with suction to remove the adhering solution as much as possible. At this time, the total weight of the cellulose (wet) which adsorbed the copper containing the adhering solution 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 on a filter paper, and then 1.5 in an oven at 50 ° C.
21. Dry for 24 hours, and cellulose adsorbing copper (dry) 21.
2 g was obtained. The content of alkali metal hydroxide measured by the neutralization titration method was 10.2%. BH-1-
Set to 2. Take 16 g of BH-1-2 and water at 5 ° C 100
It was washed with 150 ml of methanol and then dried in an oven at 50 ° C. for 1 hour to obtain 14.9 g of copper-adsorbed cellulose (after washing with water). The content of alkali metal hydroxide measured by the neutralization titration method was 5.1%. This is designated as BH-1-3. BH-1-3 7.5 g 1
Put in a 00 ml separable flask, add 42.5 g of 3% ammonia water at 15 ° C., stir, and then centrifuge to separate the supernatant through a 400-mesh stainless 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. This solution is B
H-1-3-S.

Example 2 84 g of cellulose (wet) having copper adsorbed thereon was prepared in the same manner as BH-1-1 in Example 1 except that regenerated cellulose was used as the cellulose and adsorption was carried out at 15 ° C. for 2 hours. Obtained. This is designated as BL-1-1. BL-1-1 1
Put 1.8g into a 100ml separable flask and
38.2 g of 3% ammonia water was added at 0 ° C., and the mixture was stirred, followed by centrifugation and isolation of the supernatant through a 400-mesh stainless 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 is 0.7
It was 7%. The viscosity of this solution was 35 poise.
This solution is named BL-1-1-S.

Example 3 BL-1-1 as cellulose having copper adsorbed (wet)
20. Copper-adsorbed cellulose (dry) in the same manner as BH-1-2 was prepared in Example 1 except that 62 g was used.
8 g was obtained. The content of alkali metal hydroxide measured by the neutralization titration method was 9.9%. BL-1-2
And BL-1-2 3.9 g was put into a 100 ml separable flask, and 3% ammonia water 4 at 30 ° C was added.
6.1 g was added and stirred, followed by centrifugation and 4
A cellulose copper ammonium solution was obtained by isolation through a 00 mesh stainless wire mesh. 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 named BL-1-2-S.

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

[0025]

[Table 1]

[0026]

[Table 2]

Examples 8 to 12 and Comparative Example 1 BH-1-3 was used to prepare a cellulose copper ammonium solution in the same manner as in Example 1 except that the ammonia concentration of the aqueous ammonia used was changed. The copper / cellulose ratio in these solutions was 0.52. The concentration of alkali metal hydroxide in these solutions was 0.765%. Table 3 shows the ammonia concentration (%) of the used aqueous ammonia, the cellulose concentration (%), the ammonia concentration (%) and the solution viscosity (poise) in the obtained cellulose-copper ammonium solution. Comparative Example 1
Then, the cellulose that adsorbed 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 Cellulose (wet) having copper adsorbed thereon was treated in the same manner as in Example 1 except that a pulp acid hydrolyzate was used as the cellulose and adsorption was carried out at 30 ° C. for 8 hours. Had made. Using all of this, cellulose adsorbed copper in the same manner as in Example 1 (dry) 2
8.3 g was obtained. The content of alkali metal hydroxide measured by the neutralization titration method was 9.5%. This is AH-1
-2. 3.5 g of sulfuric acid aqueous solution of various concentrations was added to 40 g of 3% ammonia water, and AH-1-2 6.
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 is 2.4.
%Met. The copper / cellulose ratio in these solutions is 0.
It was 51. Table 4 shows the concentration (%) of the aqueous sulfuric acid solution, the concentration (%) of cellulose in the ammonium copper ammonium solution, the concentration (%) of the alkali metal hydroxide and the solution viscosity (poise).
In Comparative Example 2, the cellulose having copper adsorbed was hardly dissolved in ammonia water.

[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 variously changed. All of these were dried in the same manner as in Example 1 and washed with water to obtain cellulose having copper adsorbed (after washing with water). Table 5 shows the weight (g) of the cellulose initially used, the yield (g) of the obtained copper-adsorbed cellulose (after washing with water) and the alkali metal hydroxide content (%). A cellulose-copper ammonium solution was obtained in the same manner as in Example 1 by using these celluloses (after washing with water) having adsorbed copper. The ammonia concentration in these cellulose copper ammonium solutions was 2.55%. Table 6 shows the cellulose concentration (%), the copper / cellulose ratio, the concentration (%) of the alkali metal hydroxide and the solution viscosity (poise) of the obtained cellulose-copper ammonium solution.

[0032]

[Table 5]

[0033]

[Table 6]

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

[0035]

[Table 7]

[0036]

[Table 8]

Example 23 88 g of cellulose (wet) having copper adsorbed thereon was obtained in the same manner as in Example 2 except that potassium hydroxide having the same concentration was used instead of sodium hydroxide. 12.4 g of this 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 alkali metal hydroxide in this solution was 0.96%. The viscosity of this solution was 37 poise.

Example 25 80 g of copper-wet cellulose (wet) was obtained in the same manner as in Example 2 except that lithium hydroxide having the same concentration was used instead of sodium hydroxide. 11.2 g of this was dissolved in 38.8 g of ammonia water 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 0.232 mol / l of copper hydroxide, 10.5 mol of ammonia
1 g of cellulose (hydrolyzed regenerated cellulose acid) was added to 224 ml of a copper ammonium solution containing 1 mol / l of sodium hydroxide and 0.6 mol / l of sodium hydroxide at 25 ° C., and the mixture was immersed for 1 hour as it was. Then spread this on a glass Petri dish, 50 ℃
In an oven for 6 hours to obtain 32.8 g of copper-adsorbed cellulose (dry). The alkali metal hydroxide content measured by the neutralization titration method was 17.9%.
This was washed with 1 liter of water at 5 ° C., then with 250 ml of methanol, dried in an oven at 50 ° C. for 1 hour and then 24.9.
Cellulose having adsorbed g of copper (after washing with water) was obtained. The alkali metal hydroxide content measured by the neutralization titration method is 4.
It was 8%. 7.5 g of this was placed in a 100 ml separable flask and 4% of 3% ammonia water was added at 15 ° C.
Add 2.5 g and stir, then centrifuge and discard the supernatant.
A cellulose copper ammonium solution was obtained by isolation through a 00 mesh stainless wire mesh. 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 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 20% sodium hydroxide aqueous solution 20
Suspended in 0 ml. At this time, copper hydroxide is partially dissolved in an aqueous solution of sodium hydroxide to form a deep blue color. 18.0 g of cellulose (hydrolyzed regenerated cellulose)
Was added at 10 ° C., and it was immersed as it was for 1 hour. This causes the cellulose to be colored blue. Then, the cellulose-adsorbed cellulose (wet) was filtered off from the solution on a glass filter and squeezed with suction to remove the adhering solution as much as possible. At this time, the total weight of the cellulose (wet) which adsorbed the copper containing the adhering solution was 90 g. The whole amount 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 copper-adsorbed cellulose (dry). The whole amount 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 copper-adsorbed cellulose (after washing with water). The content of alkali metal hydroxide measured by the neutralization titration method was 6.7%. 7.5 g of this was placed in a 100 ml separable flask and kept at 15 ° C. for 3 days.
% Ammonia water (42.5 g) was added and the mixture was stirred, followed by centrifugation and isolation of the supernatant through a 400-mesh stainless steel wire net to give 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 prepared in Example 1 (BH-1-3
-S) 100 g, first, using a flow tube with a draw ratio of 7 times, spinning hot water of 35 ° C. as a coagulation bath, and then regenerating in 1 l of a 3% sulfuric acid bath, washing with water and drying to regenerate the regenerated cellulose fiber. Obtained. The regenerated cellulose fiber obtained is 12
The denier was 0, the strength was 2.5 g / denier, and the elongation was 14%. The total amount of ammonia contained in the warm water in the coagulation bath after spinning was 0.1 mol. The sulfuric acid bath after spinning was sealed 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 using 100 g of a cellulose copper ammonium solution (manufactured by Asahi Kasei Bemberg Factory) currently industrially used. The concentration of cellulose in the ammonium copper ammonium 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%. The total amount of ammonia contained in the warm water of the coagulation bath after spinning was 0.3 mol. When the sulfuric acid bath after spinning was closed and left at 25 ° C., white and pale green crystals were precipitated after 2 days.

Reference Example 2 Cellulose copper ammonium solution prepared in Example 3 (BL-1-2
-S) was spun, regenerated with 1N hydrochloric acid as a coagulation bath, washed with water and dried to obtain regenerated cellulose fibers. The regenerated cellulose fiber thus obtained had a denier of 90, a strength of 1.2 g / denier and an elongation of 5%.

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

[0045]

[Table 9]

[0046]

INDUSTRIAL APPLICABILITY The present invention dramatically improves the content of copper and ammonia in the cellulose-copper ammonium solution used for producing cellulose fibers used in the field of clothing or industry, nonwoven fabrics or cellulose hollow fibers used for medical purposes. It is useful because it directly reduces the amount of chemical substances such as copper and ammonia discharged to the environment as waste liquid in the field of regenerated cellulose industry. Further, since the cellulose-copper ammonium solution is usually used under the condition that the cellulose is regenerated by being neutralized with an acid, the concentration of salts in the regenerator solution is lowered as a result when the cellulose-copper ammonium solution of the present invention is used. It is preferable that the part does not precipitate as crystals and adheres to the apparatus, which damages the regenerated cellulose fibers and the like to reduce the productivity. Further, the reduction in the amounts of copper and ammonia used leads to a reduction in the production cost of the regenerated cellulose fiber, and is also useful in this respect.

Claims (2)

[Claims] 1. Containing copper in an amount such that the molar ratio of pyranose ring to cellulose is 0.3 to 0.7, and 3% or more of cellulose and 0.1% by weight of the solution.
Ammonia in the range of 5% to 5% and 0.25% to 1%
A solution of copper-ammonium hydroxide in cellulose containing an alkali metal hydroxide in the range of 2. First, a cellulose having copper adsorbed is prepared,
Then, a method for producing a cellulose copper ammonium solution, which comprises dissolving this in an aqueous solution containing ammonia.