RU2067443C1 - Concentrate for cosmetic compositions and a method of its preparing - Google Patents

Abstract

FIELD: cosmetics. SUBSTANCE: proposed composition has thioglycolic acid salt, water, alkaline agent or organic base and hydroxyl-containing organic compounds. Developed method of composition preparing ensures to separate thioglycolic acid salts and use composition directly for cosmetic compositions making, for example, composition for cold hair twisting and agents used for hair depilation. Method involves extraction of thioglycolic acid from acid reaction mass with ethers followed by extraction of thioglycolic acid salt from ethereal solution with water and/or hydroxyl-containing organic compounds and bases at pH 9, not below. EFFECT: enhanced quality of composition, improved method of preparing.

Description

 The invention relates to the field of cosmetics for cold curling hair and removing hair from the skin of humans and animals based on thioglycolic acid and its salts.

 The use of salts of thioglycolic acid (Na, K, Ca) in cosmetic formulations is known [1. US Pat. USA 4923478] According to the patent, a hair removal product includes: salt (sodium, potassium or calcium) of thioglycolic acid, sodium stearate, propylene glycol, water. The composition of the composition for removing hair in weight.

thioglycolic acid salt (K, Na, Ca) 4-8
propylene glycol 15-60
sodium stearate 6-12
water 15-60
The composition is prepared by mixing the individual components by heating.

 A composition is proposed for the preparation of cosmetic compositions, which is obtained as a result of chemical transformations during the isolation of thioglycolic acid in the form of a salt: an alkali metal or an organic base.

 Thioglycolic acid is prepared by reacting monochloracetic acid with sodium thiosulfate, followed by hydrolysis of the resulting carboxymethylthiosulfate in an acidic medium. From the resulting acidic solution, thioglycolic acid is isolated by extraction with ether, and then distillation under high vacuum [2. A.S. 1014829] Translation of the obtained thioglycolic acid into salt is carried out by treating it with appropriate hydroxides. The disadvantage of this method of obtaining is the low yield of thioglycolic acid due to the use of distillation under high vacuum and associated with significant energy consumption. In this case, by-products are formed due to the oxidation of thioglycolic acid with atmospheric oxygen and the presence of cations of iron and other metals.

 It is proposed to obtain a salt (alkali metal or organic base) of thioglycolic acid in the form of an aqueous solution of the following composition in wt.

thioglycolic acid salt 10.30-22.30
hydroxyl-containing organic compounds 4.59-47.76
water rest
The resulting aqueous salt solution is used in various cosmetic compositions.

 A method of obtaining a salt of thioglycolic acid consists in processing the obtained ethereal solution of thioglycolic acid [by a.s. 1014829] water and / or hydroxyl-containing organic compounds and bases at a pH of at least 9, followed by separation of the aqueous layer containing a thioglycolic acid salt, water and a hydroxyl-containing compound. The ethereal solution is recycled to the extraction of thioglycolic acid.

 To obtain an ether solution of thioglycolic acid, diisopropyl ether, methyl tert-butyl ether, n-butyl tert-butyl ether, and diethyl ether were used. Obtaining an ethereal solution of thioglycolic acid is known in the literature, but to better illustrate the method for preparing the composition, examples are given of obtaining an etiological solution of thioglycolic acid.

 Ethylene glycol, glycerin, propylene glycol and their mixtures with water were used as hydroxyl-containing organic compounds. To increase efficiency, the process is carried out in an alkaline environment.

 The proposed composition and method for producing salts of thioglycolic acid in the form of a solution was not found by us in the literature. Significant differences of the method are the preparation of salts of thioglycolic acid in the form of an aqueous solution, the treatment of an ether solution of thioglycolic acid with hydroxyl-containing compounds or aqueous and alkali at a pH of at least 9.

 Significant differences in composition are: the ratio of components and the use of ethylene glycol, glycerol, ethanolamine, propylene glycol in the composition.

 The hydroxyl-containing compound (ethanolamine, glycerin, ethylene glycol, propylene glycol) used in the preparation of the salt acts as an extractant of the salt from the ethereal solution, and in the finished cosmetic compositions it plays the role of softening additives. Therefore, this method of obtaining salts of thioglycolic acid allows you to get the necessary salt in combination with the component included in the cosmetic composition.

To clarify the essence of the invention, the following implementation examples are provided, while in all the examples an acid solution of thioglycolic acid obtained from sodium chloroacetate and sodium thiosulfate was used, as described in example 1 [a.s. 1014829]
Example 1. Obtaining an ether solution.

To 72.4 g of an acidic solution containing 8.97 g (0.083 mol) of thioglycolic acid, 126 cm ^{3 of} methyl tert-butyl ether, 0.40 g of zinc dust were added, the contents were mixed until zinc was completely dissolved, transferred to a separatory funnel, sedimented, separated water and ether layers.

In the aqueous layer with a volume of 70 cm ³ contains 1.28 g (14.3%) of thioglycolic acid. With a fresh portion of ether, another 1 g (11%) of thioglycolic acid can be extracted.

The ether layer of 126 cm ³ contains 7.62 g of thioglycolic acid.

 Getting the composition.

 To 120 ml of an ethereal solution containing 7.26 g (0.0671 mol) of thioglycolic acid in methyl tert-butyl ether, 60 g of an 11.6 aqueous solution of mono-ethanolamine or 6.96 g were added, assuming 100% thoroughly mixed, transferred to separatory funnel, defended, separated layers.

Received 118 cm ^{3 of an} ether layer containing 3.08 g / l of thioglycolic acid, which is sent to obtain an ether solution and an aqueous solution containing 16.14% of the monoethanolamine salt of thioglycolic acid and 4.38% of monoethanolamine. The resulting solution was used to prepare a composition for cold curling hair type "Lock".

 Example 2. Obtaining an ether solution.

To 60 ml of an acid solution containing 8.50 g (0.0786 mol) of thioglycolic acid was added 120 cm ^{3 of} n-butyl-tert-butyl ether and 1.0 g of zinc dust, the contents were thoroughly mixed until zinc was completely dissolved, transferred to a separatory funnel, spent sludge and separation of layers. In the aqueous layer with a volume of 60 cm ^3, 1.19 g (14%) of thioglycolic acid was found.

In an ether solution of 118 cm ^3, 3.18 g / l of thioglycolic acid dissolved in n-butyl-tert-butyl ether was found. In the lower layer weighing 42.66 g contains an aqueous solution of sodium salt of thioglycolic acid composition:
thioglycolic acid sodium salt, 22.29
caustic soda, 4.36
ethylene glycol, 52.00
water, 21.35
The yield of thioglycolic acid sodium salt was 95.0%
Example 3. Obtaining an ether solution.

To 60 cm ^{3 of an} acid solution containing 8.91 g (0.0824 mol) of thioglycolic acid, 120 cm ^{3 of} diisopropyl ether, 108 g of zinc powder were added, thoroughly mixed until zinc was completely dissolved, transferred to a separatory funnel, sedimented and separated into aqueous and organic layers. 1.19 g (13.3%) of thioglycolic acid were found in a 60 ml aqueous layer. In the organic layer with a volume of 118 cm ³ found 7.75 g (87.0%) of thioglycolic acid.

 Getting the composition.

To 111 cm ^{3 of a} solution containing 7.29 g (0.0674 mol) of thioglycolic acid in diisopropyl ether, 20 cm ^{3 of} 1,3-propylene glycol, 12 cm ^{3 of a} 40% sodium hydroxide solution were added, thoroughly mixed, transferred to a separatory funnel , sucked and separated layers. 0.36 g (5.0%) was found in the upper layer of 108 cm ^{3 of} diisopropyl ether. The ether is sent to a new extraction. In the lower layer, a solution of sodium salt of thioglycolic acid with a mass of 44.77 g of the composition was obtained:
thioglycolic acid sodium salt, 21.46
caustic soda, 3.92
water, 27.92
1,3-propylene glycol, 46.70
The yield of thioglycolic acid sodium salt was 94.37% of theory. The total yield in the 3rd example was 82.10%. A solution of the sodium salt of thioglycolic acid was mixed with sodium stearate and other additives, the pH of the solution was adjusted to a value of 12-12.5 and used to obtain a cosmetic pencil for hair removal.

 Example 4. Obtaining an ether solution.

120 cm ^{3 of} diethyl ether and 1.81 g of zinc dust were added to 60 cm ^{3 of an} acid solution containing 8.72 g (0.0806 mol) of thioglycolic acid, thoroughly mixed until zinc was completely dissolved, transferred to a separatory funnel, shaken, releasing excess pressure, carried out sediment and separation into water and ether layers.

1.14 g (13.07%) of thioglycolic acid were found in a 60 cm ³ aqueous layer.

7.30 g (83.7%) of thioglycolic acid were found in the ether layer with a volume of 101 cm ³ .

 Getting the composition.

20 cm ^{3 of} glycerol and 16 cm ^{3 of a} 40.4% potassium hydroxide solution were added to 90 cm ^{3 of a} solution containing 6.51 g (0.0601 mol) of thioglycolic acid in diethyl ether, mixed, transferred to a separatory funnel, shaken, settled and separated the layers.

The upper, ethereal layer, with a volume of 88 cm ³ containing 0.33 g (5.07%) of thioglycolic acid, was sent to the first extraction.

The lower layer weighing 53.78 g contains a solution of potassium salt of thioglycolic acid composition:
potassium salt of thioglycolic acid, 19.49
water, 28.64
potassium hydroxide, 4.96
glycerin, 46.91
The output of the potassium salt of thioglycolic acid was 4.46% of theory.

The total yield in the 4th example 79.07%
Example 5. Obtaining an ether solution.

To 66.8 cm ³ or 98.6 g of an acidic solution of thioglycolic acid containing 8.29 g (0.0766 mol) and 18 g of sulfuric acid were added 150 cm ^{3 of} diisopropyl ether and 0.2 g of zinc dust, the mass was stirred at a temperature 34-38 ^o With until complete dissolution of zinc, transferred to a separatory funnel. Separation was carried out after sedimentation for at least 2 hours

0.71 g (8.6%) of thioglycolic acid was found in the lower layer of 62.6 cm ³ .

7.20 g (0.0665 mol) of thioglycolic acid were found in the upper layer with a volume of 142 cm ³ . The yield of the first extraction was 86.85% of theory.

 Getting the composition.

To a mixture of 90.0 cm ^{3 of} water and 6.6 g of monoethanolamine was added a solution of thioglycolic acid after the first extraction, stirred for 1 h, while the pH value was 9.3. The mass was transferred to a separatory funnel, defended, separated water and ether layers.

The upper, ether layer, with a volume of 140 cm ³ containing 0.37 g (5.14%) of thioglycolic acid, was sent for the first extraction.

The lower layer, a volume of 97 cm ³ solution of ethanolamine salt of thioglycolic acid composition:
ethanolamine salt of thioglycolic acid, 10.31
water, 89.03
ethanolamine, 2.66
The yield of thioglycolic acid salt was 94.65% of theory. The total yield of ethanolamine salt of thioglycolic acid in 5 example was 82.21%
An aqueous solution of monoethanolamine salt of thioglycolic acid, after adjusting the concentration by adding water and mixing with other additives, was used to obtain a preparation for cold hair curling.

 Example 6. The extraction of thioglycolic acid was carried out as described in example 3, the ether solution was sent to prepare the composition.

 Cooking composition.

15 cm ^{3 of} propylene glycol, 5 cm ^{3 of} glycerol and 12 cm ^{3 of a} 40% sodium hydroxide solution were mixed. To the resulting mixture was added 111 cm ^{3 of an} ether solution of thioglycolic acid with a content of 7.29 g (0.0674 mol), intensively mixed, transferred to a separatory funnel, and the layers were separated.

In the upper layer of 108 cm ^3, 0.36 g of thioglycolic acid dissolved in ether was found.

The bottom layer, with a volume of 38 cm ³ contains a solution of sodium salt of thioglycolic acid composition:
thioglycolic acid sodium salt, 21.32
propylene glycol 34.13
glycerin 13.63
caustic soda, 3.61
water, 27.31
The resulting solution of the sodium salt of thioglycolic acid is mixed with sodium stearate, additives, the pH was adjusted and used to obtain a cosmetic pencil for hair removal.

 Example 7. Obtaining an ethereal solution was carried out as described in example 5.

 Cooking composition.

To a mixture of 50 cm ^{3 of} water and 6.6 g of monoethanolamine was added a solution of thioglycolic acid after the first extraction, stirred for 1 h, while the pH value was 9.6. The mass was transferred to a separatory funnel, defended, separated water and ether layers.

The upper, ether layer, with a volume of 140 cm ³ , contained 0.38 g (5.28%) of thioglycolic acid.

The lower, aqueous layer, with a volume of 57 cm ^{3, a} solution of monoethanolamine salt of thioglycolic acid composition:
monoethanolamine salt of thioglycolic acid, 16.78
ethanolamine, 4.35
water, 78.87
The yield of thioglycolic acid salt was 94.5% of theory.

 Example 8

 Obtaining an ether solution.

108 cm ^{3 of} diisopropyl ether containing 0.36 g of thioglycolic acid obtained in Example 3 after the second extraction were added to 54 cm ^{3 of an} acid solution containing 8.02 g (0.0742 mol) of thioglycolic acid. Then 1.2 g of zinc dust was added, mixed thoroughly until zinc was completely dissolved, transferred to a separatory funnel, and separated into aqueous and organic layers.

 1.07 g of thioglycolic acid was found in the aqueous layer.

In the organic layer with a volume of 106 cm ³ found 7.31 g of thioglycolic acid.

 Cooking composition.

To 100 cm ^{3 of a} solution containing 6.90 g (0.0638 mol) of thioglycolic acid in diisopropyl ether were added 18 cm ^{3 of} 1,3-propylene glycol, 18 cm ^{3 of a} 40.4% potassium hydroxide solution and 5 cm ^{3 of} glycerol, the contents were thoroughly mixed, transferred to a separatory funnel, and the layers were separated.

In the upper layer with a volume of 97 cm ^3, 0.32 g of thioglycolic acid was found in diisopropyl ether. The ethereal solution was sent to a new extraction.

In the lower layer weighing 56.7 g received a solution of the potassium salt of thioglycolic acid composition:
potassium salt of thioglycolic acid, 19.85
potassium hydroxide, 5.85
glycerin, 11.12
1,3-propylene glycol, 32.85
water, 30.33.

Claims (3)

 1. A concentrate for cosmetic compositions, including a basic salt of thioglycolic acid, an emollient and water, characterized in that it contains ethylene glycol or propylene glycol, or glycerin, or a mixture thereof, or ethanolamine in the following ratio, wt. The basic salt of thioglycolic acid 10.30 22.30
Ethylene glycol, or propylene glycol, or glycerin, or mixtures thereof, or ethanolamine 2.66 52.0
Water Else
2. The concentrate according to claim 1, characterized in that as the basic salt of thioglycolic acid, it contains the sodium, potassium or monoethanolamine salt of thioglycolic acid.  3. The concentrate according to claim 1, characterized in that it further comprises caustic soda or potassium hydroxide in an amount of 3.61 5.85 wt.  4. A method of obtaining a concentrate for cosmetic compositions, including the basic salt of thioglycolic acid, characterized in that the ethereal solution of thioglycolic acid is processed per 1 wt.h. thioglycolic acid with ethylene glycol, or propylene glycol, or glycerin, or a mixture thereof in an amount of 2.8 to 3.9 parts by weight and an aqueous solution of sodium or potassium hydroxide in an amount of 0.6 to 1.5 wt.h. or water and monoethanolamine in an amount of 0.9 to 1 wt. hours and the process is carried out at a pH of not lower than 9, followed by separation of the aqueous layer containing the specified concentrate.