JP3682945B2 - Powdered carboxymethylcellulose sodium salt - Google Patents

Description

【００２２】
３．ＣＭＣの物性評価
（１）エーテル化度：灰化法により求めた。
【００２３】
（２）見掛け比重
ＣＭＣ粉末を２０ｍｌ容の容器にいれ、その時の重量（ｇ）から次式よ
りより求めた。見掛け比重＝重量／２０
【００２４】
（３）溶解性（分）
次の方法による溶解時間を測定することにより溶解性を評価した。
５００ｍｌビーカーに水４００ｍｌを採取し、スリーワンモーターで５０ｍｍφの４枚ばねプロペラ１０００ｒｐｍで攪拌する。うず巻き中にＣＭＣ４ｇをビーカー壁及び攪拌棒に付着しないように投入し、ママコがなくなり完全に溶解するまでの所要時間を測定した。
【００２５】
（４）透明性（ｃｍ）
一定光源下で、１％水溶液の透視度を液柱の高さで表したものを透明度とする（ｃｍ）。ガラス管の下に１ｍｍ間隔にひいた白黒ラインが見分けられない点を終点とした。
【００２６】
表２，表３の配合で得られたＣＭＣの上記物性を測定し、表２，表３に併せて示した。
【００２７】
【表２】

【００２８】
【表３】

【００２９】
表２，表３の結果より、本発明の粉末状ＣＭＣは溶解性及び透明性に優れているのがわかる。
【００３０】
【発明の効果】
本発明によれば、溶解性及び透明性に優れた粉末状のＣＭＣが得られる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a powdery carboxymethylcellulose sodium salt (hereinafter referred to as “CMC”) suitable for uses such as a powder syrup thickener and a powder paste because of its excellent solubility and transparency.
[0002]
[Prior art]
Conventional CMC is poorly dispersible in water and tends to be mamaco when thrown into water. For this reason, when it was going to dissolve in water, it was necessary to add little by little, performing sufficient intense stirring.
[0003]
However, since a considerable amount of time is required for dissolution, the following methods (1) to (4) for immediately dissolving CMC have been proposed and reported.
(1) A method of heating to increase solubility. (2) A method in which CMC is dispersed using a small amount of a CMC insoluble solvent such as ethanol or glycerin and then dissolved in water. (3) A method of treating CMC with glyoxal with the aim of shortening the dissolution time by preventing the occurrence of mamako. (4) A method for improving water dispersibility by heat treating CMC.
[0004]
[Problems to be solved by the invention]
However, these methods also have the following problems and are not fully satisfactory. In (1), the viscosity of CMC is reduced. In (2), ethanol, glycerin and the like in the CMC aqueous solution may become an obstacle, and a separate removal step is required. In {circle around (3)}, it takes much time and complete dissolution cannot be expected unless the pH of the medium water is made alkaline. In addition, glyoxal itself is not preferable as a food additive, and its use is restricted. (4) is characterized in that an ester bond is formed by heat treatment of a free carboxyl group, and for this reason, the pH of the aqueous solution tends to be acidic, and pH 6.0 to 8. In order to adapt to 5, it requires complicated operations such as pH adjustment.
[0005]
From the above situation, an object of the present invention is to provide a powdery CMC having excellent solubility and transparency without complicated operations and restrictions on applications.
[0006]
[Means for Solving the Problems]
The present invention has been made by paying attention to such problems, and paying attention to the fact that CMC having a low degree of etherification has good dispersibility in water and is less likely to cause mamako. It has been found that the above-mentioned problems can be overcome by mixing a certain amount, and the present invention has been achieved.
[0007]
That is, it is a powdery carboxymethylcellulose sodium salt obtained by blending 5 to 20% by weight of carboxymethylcellulose sodium salt (B) with the following carboxymethylcellulose sodium salt (A).
(A) Carboxymethylcellulose sodium salt having an etherification degree exceeding 0.5 (B) Carboxymethylcellulose sodium salt having an etherification degree of 0.4 to 0.5 and an apparent specific gravity of 0.3 to 0.5
DETAILED DESCRIPTION OF THE INVENTION
The CMC (A) used in the present invention may be any powder as long as the etherification degree exceeds 0.5, and the preferred etherification degree is 0.6 to 1.5.
[0009]
On the other hand, CMC (B) used in the present invention is a powdery CMC having an etherification degree of 0.4 to 0.5 and an apparent specific gravity of 0.3 to 0.5.
[0010]
If the degree of etherification of this CMC (B) is less than 0.4, the solution viscosity is insufficient and the transparency is insufficient due to the low carboxyl group, and if it exceeds 0.5, the water dispersibility is decreased. Absent.
[0011]
When the apparent specific gravity of CMC (B) is less than 0.3, CMC becomes cottony and is not powder, which is not preferable for handling. On the other hand, if it exceeds 0.5, it is necessary to increase the specific gravity in production, and the cost increases.
[0012]
In CMC of this invention, 5-20 weight% of CMC (B) is mix | blended with respect to the said CMC (A). If the blending amount is less than 5% by weight, the amount is not so much as to affect the immediate solubility. If the blending amount exceeds 20% by weight, the degree of etherification of the obtained CMC is lowered, and the transparency of the aqueous solution coming therefrom is lowered. 20% by weight is the limit.
[0013]
The blending method of CMC (B) measures the predetermined amount of each of CMC (A) and CMC (B), and blends by stirring with a blender type mixing stirrer at 60 rpm / 10 to 20 minutes.
[0014]
【Example】
Examples 1-12 and Comparative Examples 1-10
1. CMC used as CMC (A) is shown below.
・ Serogen WS-C (etherification degree 0.66, apparent specific gravity 0.48)
Serogen F-SB (degree of etherification 0.89, apparent specific gravity 0.49)
・ Serogen BSH-6 (etherification degree 0.72, apparent specific gravity 0.42)
・ Serogen HE-1500F (etherification degree 1.24, apparent specific gravity 0.52)
(All of the above CMC are manufactured by Daiichi Kogyo Seiyaku Co., Ltd.)
[0015]
2. CMC used as CMC (B)
Three types of CMC (CMC (X), CMC (Y), and CMC (Z)) were obtained by the following method.
[0016]
(1) Raw material isopropyl alcohol (Wako Pure Chemicals reagent grade 1), methanol (Wako Pure Chemicals reagent grade 1), caustic soda (Wako Pure Chemicals reagent grade 1), monochloroacetic acid (Wako Pure Chemicals reagent) 1st grade), sulfuric acid (1st grade reagent manufactured by Wako Pure Chemical Industries), powdered cellulose (pulverized product, polymerization degree 1600 (used for CMC (X)), polymerization degree 750 (CMC (Y) and CMC (Z) use)
[0017]
(2) Sulfuric acid for adjusting solvent neutralization (preparing 10% aqueous solution), isopropyl alcohol (hereinafter referred to as IPA, adjusting 80% aqueous solution), methanol (adjusting 75% aqueous solution)
[0018]
(3) Preparation of etherifying agent Solution A: 148 parts of caustic soda is dissolved in 2000 parts of 80% IPA and cooled to a liquid temperature of 35 ° C.
Liquid B: 59 parts of monochloroacetic acid (45 parts for CMC (Z)) are dissolved in 60 parts of 80% IPA, and the liquid temperature is adjusted to 20 ° C.
[0019]
(4) Synthesis method 200 g of powdered cellulose is charged into a 5-liter reactor having a biaxial stirring spring, and the solution A is added thereto, followed by stirring at 35 ° C. for 120 minutes. Then, after cooling to 20 ° C. over 30 minutes, B solution is charged over 30 minutes. After the addition, the mixture is stirred at 20-30 ° C. for 30 minutes, heated to 78-85 ° C. and reacted for 90 minutes. After completion of the reaction, the mixture is cooled to 40 ° C., and the crude CMC is neutralized to pH 8.0 to 8.5 with 10% sulfuric acid.
[0020]
Next, the IPA is separated from the reaction product by centrifugation (2000 rpm / 10 minutes), and purified by stirring for 20 minutes with 20% of 75% methanol (relative to crude CMC). When the obtained CMC is pulverized, CMC having a low bulk specific gravity can be obtained, but 50 parts of water (with respect to CMC100) is added and homogenized with a mixer, dried again (105 ° C./5 hours), and then pulverized to obtain a 180 μm sieve. The target CMC was obtained by subjecting it to a fluid treatment.
The physical properties of the obtained CMC (X) and CMC (Y) were measured, and the results are shown in Table 1.
[0021]
[Table 1]

[0022]
3. Physical property evaluation of CMC (1) Degree of etherification: Determined by ashing method.
[0023]
(2) Apparent specific gravity CMC powder was placed in a 20 ml container, and the weight (g) at that time was determined from the following equation. Apparent specific gravity = weight / 20
[0024]
(3) Solubility (min)
The solubility was evaluated by measuring the dissolution time according to the following method.
400 ml of water is collected in a 500 ml beaker and stirred with a three-one motor with a 50 mmφ four-spring propeller at 1000 rpm. During swirling, 4 g of CMC was added so as not to adhere to the beaker wall and the stirring rod, and the time required until mamako disappeared and completely dissolved was measured.
[0025]
(4) Transparency (cm)
Under a constant light source, the transparency of a 1% aqueous solution expressed as the height of the liquid column is defined as transparency (cm). The end point was a point where black and white lines drawn at intervals of 1 mm could not be distinguished under the glass tube.
[0026]
The above-mentioned physical properties of CMC obtained by the blending of Tables 2 and 3 were measured and are shown together in Tables 2 and 3.
[0027]
[Table 2]

[0028]
[Table 3]

[0029]
From the results of Tables 2 and 3, it can be seen that the powdered CMC of the present invention is excellent in solubility and transparency.
[0030]
【The invention's effect】
According to the present invention, a powdery CMC having excellent solubility and transparency can be obtained.

Claims (1)

Powdered carboxymethylcellulose sodium salt obtained by blending 5 to 20% by weight of carboxymethylcellulose sodium salt (B) with respect to the following carboxymethylcellulose sodium salt (A).
(A) Carboxymethylcellulose sodium salt with an etherification degree exceeding 0.5 (B) Carboxymethylcellulose sodium salt with an etherification degree of 0.4 to 0.5 and an apparent specific gravity of 0.3 to 0.5