JPS6041674B2 - Method for producing dried phosphate ester salt - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing an odorless phosphate ester salt dry product.

Phosphate esters of organic hydroxy compounds such as aliphatic alcohols and phosphate ester salts such as their alkali metal and alkanolamine salts are used in a wide range of fields such as cleaning agents, textile treatment agents, metal surface treatment agents, emulsifiers, etc. .

In particular, the salt of monoalkyl phosphate having a long-chain alkyl group is water-soluble, has good foaming power and cleansing power, and has low toxicity and skin irritation, so it cannot be directly applied to the human body. It is useful as a base material for cleaning agents such as facial cleansers, bath additives, similar cleaning agents, and shampoos. Among these, alkali metal salts such as sodium and potassium salts of monoalkyl phosphoric acid esters are particularly useful as base materials for the same type or pasty detergents.

However, since the cleaning agent is scented with a fragrance or used unscented, it is necessary that the cleaning agent itself be odorless and dry in order to be used for this purpose. usually,
Dried organic solvent J agent alkali metal salts such as monoalkyl phosphate esters are organic hydroxy compounds containing phosphorus pentoxide,
A phosphoric acid esterifying agent such as polyphosphoric acid or phosphorus oxychloride is applied to form an acidic phosphate ester, which is then neutralized with caustic soda or caustic potash to form a phosphate ester alkali metal salt, and further processed by methods such as spray drying. Manufactured by drying.

However, the dried product of the alkali metal phosphate ester produced by this method has an odor and cannot be used as a base material for the above-mentioned cleaning agent.

Therefore, the present inventors have conducted various studies on a method for producing an odorless alkali metal phosphate ester dry product. As a result, we have found that, in an organic solvent with a boiling point of 100°C or less that can be dissolved in water at any ratio, carbon The acidic phosphoric acid ester of aliphatic alcohol having numbers 8 to 18 is neutralized with caustic soda or caustic potash, or an aqueous solution of the sodium salt or potassium salt of the phosphoric ester is mixed with the above-mentioned barbed solvent, and the phosphoric acid thus generated is It was discovered that by separating the precipitate of the sodium salt or potassium salt of the acid ester and removing the organic solvent contained in the precipitate, an odorless dried product of the sodium or potassium salt of the phosphoric acid ester can be produced, and the present invention has been made based on the present invention. completed.

As mentioned above, the organic solvent used in the present invention is one that can be mutually soluble with water in any ratio, has a boiling point of 100°C, preferably 85°C or less, and hardly reacts with the acidic phosphoric ester. For example, acetone, methanol, ethanol, isopropanol, etc. may be mentioned, and for the above purpose, acetone or methanol is particularly preferred. Butanol, methyl ethyl ketone and the like have limited mutual solubility with water and are therefore not preferred for the purposes of the present invention. Further, the organic solvent may be a water-containing organic solvent containing water to the extent that the object of the present invention is not impaired. To carry out the present invention, first, an acidic phosphoric acid ester of an aliphatic alcohol having 8 to 18 carbon atoms produced by a conventional method is dissolved in the above-mentioned organic solvent, and the temperature is preferably below the boiling point of the organic solvent. Neutralize by gradually adding caustic soda or an aqueous solution of caustic potash under stirring at a temperature of 20 to 50°C, or combine an aqueous solution of the sodium salt or potassium salt of the phosphoric acid ester prepared by a conventional method with the above organic solvent. Below boiling point, preferably 20-50℃
Mix at a temperature of

In doing so, the sodium or potassium salt of the phosphoric ester is obtained as a precipitate. Next, the resulting precipitate of the sodium salt or potassium salt of the phosphoric acid ester is separated from the organic solvent by a method such as filtration or centrifugation. The separated precipitate can be further washed with the organic solvent as necessary, and the organic solvent contained therein can be removed by a method such as a nitrogen stream or reduced pressure to obtain odorless sodium phosphate ester. A dry salt or potassium salt is obtained. As mentioned above, it was difficult to remove the odor from powder products obtained by conventional methods such as spray drying, even when washed with various solvents, but the method of the present invention eliminates this odor. Odors can be completely removed, and at the same time, excellent dry powder with low moisture content can be obtained through a simple process.

Examples will be further described below.

Example 1 After uniformly dissolving 100 parts of lauryl phosphate ester (acid value 20 at the first equivalence point & acid value 390 at the second equivalence point) in 440 parts of acetone containing 1% water by volume at 40°C, 37.4 parts of a 48% caustic soda aqueous solution is gradually added while stirring at a temperature of 40 to 45°C to neutralize.

After neutralization, the temperature was gradually cooled to 20'C while stirring, and after stirring was continued for a while at 20C, the white precipitate formed was separated. The separated white precipitate was diluted with acetone 4 (
4) After washing twice in portions, the acetone contained in the white precipitate was removed with a nitrogen stream to obtain a white powder of sodium salt of lauryl phosphate containing 5.3% water. A sensory evaluation of the odor of this 1% aqueous solution of sodium salt of lauryl phosphate at 50° C. by a panel of three experts revealed that it was almost odorless.

Example 2 Same lauryl phosphate 100 as Example 1
Part and 21. 81.3 parts of a caustic soda aqueous solution having a weight of % was mixed and neutralized at a temperature of 50 to 60°C to produce a sodium salt of lauryl phosphate.

During the neutralization reaction, the pH (1% solid aqueous solution; 30°C) was adjusted to 6 to
Adjusted to be 8. One (1) part of a 60.5% aqueous solution of the obtained sodium lauryl phosphate salt was gradually added to two parts of acetone with stirring, and the white precipitate formed was separated. The separated white precipitate is washed twice with 240 parts of acetone each time, and then the acetone contained in the white precipitate is removed under reduced pressure to obtain 57 parts of white powder of sodium lauryl phosphate containing 5.6% water. Obtained. 5 of this 1% aqueous solution of sodium lauryl phosphate ester
As a result of sensory evaluation of the odor at 0°C by a panel of three experts, it was found to be almost odorless.

Example 3 After uniformly dissolving 10 parts of myristyl phosphate (acid value at the first equivalent point: 18λ, acid value at the second equivalent point: 355) in 4 (1) parts of methanol at 40°C, 40% of a 40% caustic soda aqueous solution was added. Add 0.5 parts gradually at a temperature of 40-45°C with stirring to neutralize.

After neutralization, the temperature was gradually cooled to 20° C. while stirring, and after stirring was continued for a while at 20° C., the white precipitate formed was separated. The separated white precipitate was mixed with methanol 4
After washing twice with a hammer, the methanol contained in the white precipitate was removed under reduced pressure to obtain 105 parts of a white powder of sodium salt of myristyl phosphate containing 3.9% water. 1 of this sodium salt of myristyl phosphate
A panel of three experts evaluated the odor of the % aqueous solution at 50°C and found that it was almost odorless.

Example 4 100 parts of cetyl phosphate (acid value 127 at the first equivalence point, acid value 185 at the second equivalence point) was mixed with 40 parts of ethanol (
After uniformly dissolving in 2) at 40°C, 38.0 parts of a 40% caustic potash aqueous solution is gradually added to the solution while stirring at a temperature of 40 to 45°C to neutralize.

After neutralization, gradually cool to 20°C while continuing to stir.
After stirring for a while at a temperature of 20° C., the white precipitate formed is separated. After washing the separated white precipitate twice with 40 parts of ethanol, the ethanol contained in the white precipitate was removed under reduced pressure to obtain 1 part of a white powder of potassium salt of cetyl phosphate containing 2.4% water. Ta. The odor of this 1% aqueous solution of potassium salt of cetyl phosphate at 50°C was evaluated by a panel of three experts and found to be almost odorless. Comparative Example 100 parts of the same lauryl phosphate ester as in Example 1 was added to 4.
A sodium salt aqueous solution of lauryl phosphate ester with a solid content of 23% obtained by neutralizing with 378 parts of a 75% caustic soda aqueous solution was heated at a hot air temperature of 180°C and a spray drying tower internal temperature of 85°C.
A white powder of sodium salt of lauryl phosphate containing 4.8% water was obtained by spray drying at a spray pressure of 110k9/DGl stock solution temperature of 50°C.

Claims (1)

[Scope of Claims] 1. In an organic solvent with a boiling point of 100°C or less that can be dissolved in any ratio with water, an acidic phosphoric acid ester of an aliphatic alcohol having 8 to 18 carbon atoms is neutralized with caustic soda or caustic potash, or Alternatively, an aqueous solution of the sodium salt or potassium salt of the phosphoric ester is mixed with the organic solvent, the precipitate of the sodium salt or potassium salt of the phosphoric ester thus produced is separated, and the organic solvent contained in the precipitate is removed. A method for producing a dried sodium salt or potassium salt of a phosphoric acid ester, which method comprises removing the sodium salt or potassium salt of a phosphoric acid ester. 2. The method for producing a dried sodium salt or potassium salt of a phosphoric acid ester according to claim 1, wherein the organic solvent is any one of acetone, methanol, ethanol, or isopropanol.