JPH0678361B2 - A new method for producing carboxymethyl cellulose calcium - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel process for producing calcium carboxymethyl cellulose from acid carboxymethyl cellulose.

[0002]

2. Description of the Related Art Carboxymethyl cellulose calcium (hereinafter referred to as Ca-CMC) has been conventionally used as a disintegrating agent for tablets of pharmaceuticals, foods, etc. It has been found that it can also be used for reinforcement.

As the production method thereof, as shown in Japanese Patent Publication No. 43-7960 and Japanese Patent Application Laid-Open No. 60-47001, carboxymethyl cellulose at a high solid content (30 to 80% to 20 to 70%). Calcium carbonate or calcium carbonate and calcium hydroxide are added to an acid (hereinafter referred to as "H-CMC") in an amount of 70 to 80% of an equimolar amount of the carboxymethyl group substitution degree, and reacted to have a low viscosity and no tackiness It has gained.

That is, since the reaction product is produced in a state where it does not gelatinize (coagulate), it was produced in a relatively weakly acidic to neutral range with a pH of 4 to less than 7.

[0005]

SUMMARY OF THE INVENTION We have found that Ca-C has various substitution degrees and viscosities required in various applications.
The present invention has been reached by searching for a manufacturing method for providing MC.

[0006]

That is, the production of carboxymethyl cellulose calcium according to the present invention is carried out by dispersing raw material carboxymethyl cellulose acid in water at a solid content concentration of 3 to 20%, preferably 5 to 10%. The degree of substitution per glucose unit and this mol of calcium hydroxide are added to gelatinize, and the temperature is raised to 50 ° C or higher, preferably 70 ° C to replace and bond the hydrogen atom of carboxymethylcellulose acid with the calcium atom of calcium hydroxide. After that, a solvent is added so that the alcohol concentration becomes 30% or more to insolubilize and precipitate carboxymethylcellulose calcium.

When the solid content concentration exceeds 20%, gelatinized carboxymethylcellulose calcium is coated with carboxymethylcellulose acid to form mamako, which inhibits internal penetration of calcium, resulting in insufficient substitution and binding. Viscosity does not develop. On the other hand, when the solid content concentration is 3% or less,
Although internal penetration of calcium is improved, productivity and amount of added solvent are increased, which is not industrially suitable. Also, the reaction temperature
Even when the temperature is lower than 50 ° C, the reaction between calcium and carboxymethylcellulose acid is inhibited and the viscosity is not expressed.

Carboxymethylcellulose acid, which is the starting material of the present invention, is industrially obtained by treating sodium carboxymethylcellulose with a strong acid such as sulfuric acid or hydrochloric acid to remove by-produced salts.

The alcohol used may be methanol, ethanol or isopropyl alcohol, and acetone may be used.

[0010]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto.

Example 1 A biaxial kneader having a capacity of 5 liters had a carboxymethylation degree of 0.
At 47, add 100 parts of carboxymethyl cellulose acid having a solid content of 30%, add 360 parts of water, and stir and mix. Disperse and add 2.77 parts by weight of calcium hydroxide in 30 parts of water and confirm that the pH is between 5.0 and 7.0 while stirring and mixing at room temperature for 60 minutes. It took 30 minutes to raise the temperature to 70 ° C,
This temperature is maintained for 60 minutes to complete the substitution and bonding.
After cooling to room temperature and adding 307 parts of 99% methyl alcohol to precipitate a gelatinized product of carboxymethyl cellulose calcium as insoluble, deliquoring, drying, crushing and classification were carried out to obtain 25 parts of carboxymethyl cellulose calcium.
The analysis was performed and the results are shown in the table.

Example-2 A biaxial kneader having a capacity of 5 liters had a carboxymethylation degree of 0.
At 53, add 100 parts of carboxymethyl cellulose acid having a solid content of 30%, add 360 parts of water, and stir and mix. Add 3.06 parts by weight of calcium hydroxide dispersed in 30 parts of water, and stir at room temperature for 60 minutes while mixing to confirm that the pH is between 5.0 and 7.0. It took 30 minutes to raise the temperature to 70 ° C,
This temperature is maintained for 60 minutes to complete the substitution and bonding.
After cooling to room temperature and adding 329 parts of 99% methyl alcohol to precipitate a gelatinized product of carboxymethyl cellulose calcium as insoluble, deliquoring, drying, crushing and classification were carried out to obtain 25 parts of carboxymethyl cellulose calcium.
The analysis was performed and the results are shown in the table.

Example 3 A carboxymethylation degree of 0.5 was added to a biaxial kneader having a capacity of 5 liters.
At 70, add 100 parts of carboxymethyl cellulose acid having a solid content of 30%, add 360 parts of water, and stir and mix. Disperse and add 3.84 parts by weight of calcium hydroxide in 30 parts of water and confirm that the pH is between 5.0 and 7.0 while stirring and mixing at room temperature for 60 minutes. It took 30 minutes to raise the temperature to 70 ° C,
This temperature is maintained for 60 minutes to complete the substitution and bonding.
After cooling to room temperature and adding 400 parts of 99% methyl alcohol to precipitate a gelatinized product of carboxymethyl cellulose calcium as insoluble, deliquoring, drying, pulverizing and classifying to obtain 26 parts of carboxymethyl cellulose calcium.
The analysis was performed and the results are shown in the table.

Example 4 A carboxymethylation degree of 0.
At 86, add 100 parts of carboxymethyl cellulose acid having a solid content of 30%, add 360 parts of water, and stir and mix. Disperse 4.5 parts by weight of calcium hydroxide in 30 parts of water and stir at room temperature for 60 minutes while mixing to confirm that the pH is between 5.0 and 7.0. It took 30 minutes to raise the temperature to 70 ° C,
This temperature is maintained for 60 minutes to complete the substitution and bonding.
After cooling to room temperature and adding 450 parts of 99% methyl alcohol to precipitate a gelatinized product of carboxymethyl cellulose calcium as insoluble, deliquoring, drying, crushing and classification were performed to obtain 26 parts of carboxymethyl cellulose calcium.
The analysis was performed and the results are shown in the table.

Example 5 A carboxymethylation degree of 1.
At 53, add 100 parts of carboxymethyl cellulose acid having a solid content of 30%, add 360 parts of water, and stir and mix. Disperse 6.77 parts by weight of calcium hydroxide in 30 parts of water, and stir at room temperature for 60 minutes while mixing, and confirm that the pH is between 5.0 and 7.0. It took 30 minutes to raise the temperature to 70 ° C,
This temperature is maintained for 60 minutes to complete the substitution and bonding.
After cooling to room temperature and adding 600 parts of 99% methyl alcohol to precipitate a gelatinized product of carboxymethyl cellulose calcium as insoluble, deliquoring, drying, crushing and classification were carried out to obtain 27 parts of carboxymethyl cellulose calcium.
The analysis was performed and the results are shown in the table.

COMPARATIVE EXAMPLE-1 A biaxial kneader having a capacity of 5 liters had a carboxymethylation degree of 0.
Carboxymethyl cellulose acid with solid content of 30% at 53
Add 100 parts, add 3.0 parts by weight calcium carbonate,
The mixture was reacted at 35 ° C. for 2 hours, dried, pulverized and classified to obtain 26 parts. The analysis was performed and the results are shown in the table.

Comparative Example-2 A carboxymethylation degree of 0.
Carboxymethyl cellulose acid with solid content of 30% at 53
100 parts was added and 1.3 parts by weight of calcium carbonate (Comparative Example-1
(43.3% of the calcium-containing agent) and stirred at a temperature of 35 ° C for 1 hour and mixed, and then 1.26 parts by weight of calcium hydroxide (56.7%).
(Corresponding to mol%) and further reacted at 35 ° C for 1 hour,
It was dried, crushed and classified to obtain 26 parts. The analysis was performed and the results are shown in the table.

Comparative Example 3 A carboxymethylation degree of 0.
Carboxymethyl cellulose acid with solid content of 30% at 53
Add 100 parts, add 1.23 parts by weight of calcium hydroxide and react for 1 hour at a temperature of 35 ° C., then add 1.00 parts by weight of calcium hydroxide and react for 1 hour at 35 ° C., dry, crush and classify. I got a part. The analysis was performed and the results are shown in the table. The properties of the obtained Ca-CMC are as shown in the table below.

[0019]

From the table, the following can be recognized. Comparative Example-1
Comparative Example 3 (Japanese Patent Publication No. 43-7960 and Japanese Patent Laid-Open No. 60-470)
The viscosity development of Examples-1 to 5 is clear as compared with those produced based on the Example of JP-A No. 01).

The properties of carboxymethylcellulose calcium shown in the table are (1) loss on drying, (2) pH, (3) 3
The method for measuring% viscosity and (4) ash content is as follows.

(1) Weight loss on drying 1 g of the sample was dried at 105 ° C. for 4 hours, and the weight loss on drying was calculated from the following formula.

(2) 100 g of water was added to 1 g of the pH sample, and the mixture was shaken to prepare a suspension, and the suspension was measured with a pH meter.

(3) 3% viscosity 15 g of a sample was sampled in a 500 ml beaker, 400 ml of water was added,
Dissolve using a triangle stir bar. The amount of water is adjusted so that the sample concentration is 3% by absolute dry weight, and the viscosity is read using a B-type viscometer after rotating at 30 rpm for 3 minutes.

(4) Ash content 1 g of a sample was sampled in a platinum dish or a porcelain crucible, and 700 to 750
Ash at ℃ for 3 hours, and obtain the ash from the following formula.

[0026]

As described in detail in the examples, the water content is 80 to 97%,
The present invention has been completed by adding an equimolar amount of calcium hydroxide to carboxymethylcellulose acid having a solid content of 3 to 20% and having a high water content, to give viscous Ca-CMC.

Claims (2)

[Claims] 1. In the production of carboxymethylcellulose calcium from acid-type carboxymethylcellulose, the degree of substitution of calcium hydroxide with carboxymethyl group for carboxymethylcellulose acid having a water content of 80-97% and a solid content of 3-20%. 50 ~ after adding and mixing equimolar amount
Carboxymethyl cellulose calcium which is characterized in that the temperature is maintained at 90 ° C. and alcohol or acetone is further added so that the concentration becomes 30% or more, and the precipitated carboxymethyl cellulose calcium is deliquored, dried, crushed and classified. Manufacturing method. 2. The alcohol is methanol, ethanol,
The method for producing carboxymethyl cellulose calcium according to claim 1, which is one of isopropyl alcohol.