Process for preparing acylglycinates and compositions comprising such compounds

Abstract

A process for preparing acylglycinates of the formula (I) wherein R.sup.1 is a linear or branched, saturated alkanoyl group having 6 to 30 carbon atoms, or is a linear or branched, singly or multiply unsaturated alkenoyl group having 6 to 30 carbon atoms, and Q.sup.+ is a cation, wherein glycine is reacted with fatty acid chloride R.sup.1Cl, in water and in the presence of a basic alkali metal compound which yields cations Q.sup.+, but in the absence of organic solvents, at 25-50 C. Also described are compositions comprising acylglycinates of the formula (I). ##STR00001##

Claims

1. A composition comprising a) at least one acylglycinate of the formula (I) ##STR00006## in which R.sup.1 is a linear or branched, saturated alkanoyl group having 6 to 30 carbon atoms, or a linear or branched, mono- or polyunsaturated alkenoyl group having 6 to 30 carbon atoms, and Q.sup.+ is a cation selected from the group consisting of the alkali metal cations Na.sup.+ and K.sup.+, in amounts of 21.0-28.0% by weight, based on the overall composition, and where, in the at least one acylglycinate of the formula (I), the proportion of saturated C.sub.8 acyl groups is 5.0-8.0% by weight, the proportion of saturated C.sub.10 acyl groups is 5.0-8.0% by weight, the proportion of C.sub.12 acyl groups is 44.0-50.0% by weight, the proportion of C.sub.14 acyl groups is 14.0-20.0% by weight, the proportion of C.sub.16 acyl groups is 8.0-10.0% by weight, the proportion of saturated C.sub.18 acyl groups is 1.0-3.0% by weight and the proportion of unsaturated C.sub.18 acyl groups is 4.0-10.0% by weight, and where the proportions are based on the total amount of acyl groups present in the at least one acylglycinate, but are calculated not on the basis of the acyl groups but on the basis of the fatty acid chlorides corresponding to the acyl groups b) at least one substance Q.sup.+Cl.sup. in which Q.sup.+ is as defined for Q.sup.+ in formula (I), in amounts greater than or equal to 1.0% by weight, based on the overall composition, c) at least one fatty acid salt of the formula (II) ##STR00007## in which R.sup.2CO is as defined for R.sup.1 in formula (I) and Q.sup.+ is as defined for Q.sup.+ in formula (I), in amounts less than or equal to 3.0% by weight, based on the overall composition, and d) water, e) and no organic solvents.

2. The composition as claimed in claim 1, which comprises 23.0-27.0% by weight of component a), based on the overall composition.

3. The composition as claimed in claim 1, wherein Q.sup.+ is Na.sup.+.

4. The composition as claimed in claim 1, which comprises 1.0 to 8.0% by weight of the at least one substance Q.sup.+Cl.sup., based on the overall composition.

5. The composition as claimed in claim 1, which comprises the at least one fatty acid salt of the formula (II) in amounts of 0.01 to 2.0% by weight, based on the overall composition.

6. The composition as claimed in claim 1, wherein the purity of the acylglycinate of the formula (I) present therein is 90% or greater, this purity being based on the sum total of fatty acid salt of the formula (II) and acylglycinate of the formula (I), and being calculated as purity of the acylglycinates is equal to the amount of acylglycinate divided by (the amount of acylglycinate plus the amount of fatty acid salt).

7. The composition as claimed in claim 1, which has a viscosity of less than 5000 mPa.Math.s at 40 C.

8. A process for production of a cosmetic formulation comprising the step of adding a composition as claimed in claim 1 to the cosmetic formulation.

9. A surfactant in a cosmetic formulation comprising at least one composition as claimed in claim 1.

Description

COMPARATIVE EXAMPLE 1

Cocoyl Chloride (A): Coconut Cut with Reduced C16 and C18 Component

(1) Specification of the cocoyl chloride used:

(2) C.sub.8/C.sub.10 saturated: 10.0-14.0% by weight

(3) C.sub.12: 60.0-62.0% by weight

(4) C.sub.14: 19.0-24.0% by weight

(5) C.sub.16: 3.0-10.0% by weight

(6) C.sub.18 saturated: <2.0% by weight

(7) 37.8 g (0.504 mol) of glycine are dissolved in 276 g of demineralized water while stirring, and the pH (tel quel) is set to 12-13 with sodium hydroxide solution (33% by weight in water). Subsequently, the mixture is heated to 30-35 C. while stirring and 106.4 g (0.478 mol) of cocoyl chloride (A) are metered in at 30-35 C. while cooling the reaction mixture within 6 hours. The pH is kept at 12-13 by simultaneous metered addition of sodium hydroxide solution (33% by weight in water). Toward the end of the metered addition of the cocoyl chloride, the pH is allowed to drop to 9.5-10.5. To complete the reaction, the mixture is stirred at pH 9.5-10.5 for another 2 hours.

(8) The product obtained has the following properties:

(9) at 25 C.: liquid, opalescent

(10) dry residue (1 hour, 140 C.): 31.0% by weight

(11) glycine salt (HPLC): 0.6% by weight

(12) fatty acid salt (HPLC): 0.6% by weight

(13) NaCl (titration): 5.3% by weight

(14) active content: 24.5% by weight

(15) viscosity (35 C.): 756 mPa.Math.s

(16) The weight of acylglycinate in the compositions is calculated by the formula weight of acylglycinate=dry residuefatty acid saltglycine saltQ.sup.+Cl.sup.. The value is referred to as active content in the context of the present application.

(17) Comparative example 1 corresponds to the prior art of WO 2009/065530. This affords a solution, liquid at room temperature (25 C.), of sodium cocoylglycinate, but this is based on a chain cut of lower commercial availability.

COMPARATIVE EXAMPLE 2

Coconut Cut with Increased C16/18 Component but without C8 and C10 Component

(18) Distribution of the cocoyl chloride used (B):

(19) C.sub.12: 55.6% by weight

(20) C.sub.14: 23.0% by weight

(21) C.sub.15: 11.1% by weight

(22) C.sub.18 saturated: 10.3% by weight

(23) 36.0 g (0.480 mol) of glycine are dissolved in 280 g of demineralized water while stirring, and the pH (tel quel) is set to 12-13 with sodium hydroxide solution (33% by weight in water). Subsequently, the mixture is heated to 30-35 C. while stirring and 109.6 g (0.456 mol) of cocoyl chloride (B) are metered in at 30-35 C. while cooing the reaction mixture within 6 hours. The pH is kept at 12-13 by simultaneous metered addition of sodium hydroxide solution (33% by weight in water). In the course of the metered addition of the cocoyl chloride, the mixture becomes ever more viscous until it is no longer stirrable. Through addition of 110 g of water and a subsequent increase in the reaction temperature to 40 C., the reaction mixture remains stirrable to a certain degree. Toward the end of the metered addition of the cocoyl chloride, the pH is allowed to drop to 9.5-10.5. To complete the reaction, the mixture is stirred at pH 9.5-10.5 for another 2 hours.

(24) The product obtained has the following properties:

(25) at 25 C.: liquid, cloudy

(26) dry residue (1 hour, 140 C.): 25.8% by weight

(27) glycine salt (HPLC): 0.8% by weight

(28) fatty acid salt (HPLC): 1.2% by weight

(29) NaCl (titration): 4.1% by weight

(30) active content: 19.7% by weight

(31) viscosity: not determined

(32) Comparative example 2 shows that higher contents of saturated C.sub.16/18 fatty acid chlorides lead to glycinate solutions which are of low concentration and cannot be handled if no C.sub.8, C.sub.10 and unsaturated C.sub.18 acid chloride components are present in the acid chloride.

EXAMPLE 1

Coconut Cut with C8 and C10 Components and Unsaturated C18 Components

(33) Distribution of the cocoyl chloride used:

(34) TABLE-US-00001 Fatty acid chloride % by weight C.sub.6 fatty acid chloride 0.5 C.sub.8 fatty acid chloride, saturated 7.4 C.sub.10 fatty acid chloride, saturated 5.9 C.sub.12 fatty acid chloride 49.4 C.sub.14 fatty acid chloride 18.5 C.sub.16 fatty acid chloride 8.4 C.sub.18 fatty acid chloride, 5.2 unsaturated C.sub.18 fatty acid chloride, saturated 2.2 Sum total x 2.5 x: indeterminate substances

(35) 18.9 g (0.252 mol) of glycine are dissolved in 146 g of demineralized water while stirring, and the pH (tel quel) is set to 12-13 with sodium hydroxide solution (33% by weight in water). Subsequently, the mixture is heated to 35-40 C. while stirring and 53.1 g (0.239 mol) of cocoyl chloride are metered in at 35-40 C. while cooling the reaction mixture within 6 hours. The pH is kept at 12-13 by simultaneous metered addition of sodium hydroxide solution (33% by weight in water). Toward the end of the metered addition of the cocoyl chloride, the pH is allowed to drop to 9.5-10.5. To complete the reaction, the mixture is stirred at 40 C. and pH 9.5-10.5 for another 2 hours.

(36) The product obtained has the following properties:

(37) at 40 C.: mobile, clear, homogeneous

(38) dry residue (1 hour, 140 C.): 30.0% by weight

(39) glycine salt (HPLC): 0.9% by weight

(40) fatty acid salt (HPLC): 1.8% by weight

(41) NaCl (titration): 5.0% by weight

(42) active content: 22.3% by weight

(43) viscosity (40 C.): 100 mPa.Math.s

(44) Inventive example 1 shows that homogeneous glycinate solutions having a high active content are obtained with fatty acid chlorides comprising both significant amounts of C.sub.8 and C.sub.10 fatty acid chloride and unsaturated C.sub.18 fatty acid chloride (chain cut corresponding to a naturally occurring coconut fatty acid cut).

COMPARATIVE EXAMPLE 3

Coconut Cut with Unsaturated C18 Components but Small C8 and C10 Components

(45) Distribution of the cocoyl chloride used:

(46) TABLE-US-00002 Fatty acid chloride % by weight C.sub.8 fatty acid chloride, saturated 0.1 C.sub.10 fatty acid chloride, saturated 0.5 C.sub.12 fatty acid chloride 55.1 C.sub.14 fatty acid chloride 23.0 C.sub.16 fatty acid chloride 10.7 C.sub.18 fatty acid chloride, 6.8 unsaturated C.sub.18 fatty acid chloride, saturated 2.9 Sum total x 1.0 x: indeterminate substances

(47) 18.9 g (0.252 mol) of glycine are dissolved in 155 g of demineralized water while stirring, and the pH (tel quel) is set to 12-13 with sodium hydroxide solution (33% by weight in water). Subsequently, the mixture is heated to 35-40 C. while stirring and 57.2 g (0.239 mol) of cocoyl chloride are metered in at 35-40 C. while cooling the reaction mixture within 6 hours. The pH is kept at 12-13 by simultaneous metered addition of sodium hydroxide solution (33% by weight in water). In the course of the metered addition of the cocoyl chloride, the mixture becomes ever more viscous until it is ultimately no longer stirrable. This makes it necessary to raise the temperature first to 45 C. and then to 50 C. In spite of this, the mixture remains viscous. Toward the end of the metered addition of the cocoyl chloride, the pH is allowed to drop to 9.5-10.5. To complete the reaction, the mixture is stirred at 50 C. and pH 9.5-10.5 for another 2 hours.

(48) The product obtained has the following properties:

(49) at 40 C.: unstirrable viscous material

(50) dry residue (1 hour, 140 C.): 31.2% by weight

(51) glycine salt (HPLC): 2.5% by weight

(52) fatty acid salt (HPLC): 4.4% by weight

(53) NaCl (titration): 4.6% by weight

(54) active content: 19.7% by weight

(55) viscosity: not determined

(56) Comparative example 3 shows that only unstirrable viscous materials having low purity are obtained as products at 40 C. with fatty acid chlorides comprising no significant amounts of C.sub.8 and C.sub.10 fatty acid chloride but comprising significant amounts of unsaturated C.sub.18 fatty acid chloride (corresponding to a commercial, naturally occurring coconut fatty acid cut which has been capped).

EXAMPLE 2

(57) Coconut cut with unsaturated components from comparative example 3, supplemented with C.sub.8 and C.sub.10

(58) Distribution of the cocoyl chloride used:

(59) TABLE-US-00003 Fatty acid chloride % by weight C.sub.8 fatty acid chloride, saturated 5.0 C.sub.10 fatty acid chloride, saturated 8.0 C.sub.12 fatty acid chloride 48.3 C.sub.14 fatty acid chloride 20.1 C.sub.16 fatty acid chloride 9.3 C.sub.18 fatty acid chloride, 5.8 unsaturated C.sub.18 fatty acid chloride, saturated 2.5 Sum total x 1.0 x: indeterminate substances

(60) 18.9 g (0.252 mol) of glycine are dissolved in 156 g of demineralized water while stirring, and the pH (tel quel) is set to 12-13 with sodium hydroxide solution (33% by weight in water). Subsequently, the mixture is heated to 35-40 C. while stirring and 55.5 g (0.239 mol) of cocoyl chloride are metered in at 35-40 C. while cooling the reaction mixture within 6 hours. The pH is kept at 12-13 by simultaneous metered addition of sodium hydroxide, solution (33% by weight in water). The mixture has good stirrability. Toward the end of the metered addition of the cocoyl chloride, the pH is allowed to drop to 9.5-10.5. To complete the reaction, the mixture is stirred at 40 C. and pH 9.5-10.5 for another 2 hours.

(61) The product obtained has the following properties:

(62) at 40 C.: mobile, clear, homogeneous

(63) dry residue (1 hour, 140 C.): 29.7% by weight

(64) glycine salt (HPLC): 0.8% by weight

(65) fatty acid salt (HPLC): 1.9% by weight

(66) NaCl (titration): 4.6% by weight

(67) active content: 22.4% by weight

(68) viscosity (40 C.): 388 mPa.Math.s

(69) Inventive example 2 shows that glycinate solutions which are homogeneous at 40 C. and have a high active content are obtained with fatty acid chlorides comprising significant amounts both of C.sub.8 and C.sub.10 fatty acid chloride and of unsaturated C.sub.18 fatty acid chloride (chain cut corresponding to a naturally occurring coconut fatty acid cut).

COMPARATIVE EXAMPLE A

(70) Foaming capacity of the inventive compositions:

(71) The foaming capacity was measured in an SITA foam tester at a surfactant concentration of 0.01% by weight at pH=9 and 37 C. Table 1 below collates the foam heights as a function of the stirring cycles.

(72) TABLE-US-00004 TABLE 1 Foam heights measured [mm] as a function of the stirring cycles Stirring cycles 2 4 6 8 10 15 20 25 30 Foam 22 60 98 130 150 195 225 235 245 heights [mm] Example 1 Foam 96 130 130 130 130 130 130 130 130 heights [mm] Com- parative example 1

(73) The experimental results collated in table 1 show that the inventive acylglycinate enables, or the inventive compositions enable, much higher achievable total foam heights than the acylglycinate or the composition from comparative example 1. The high achievable total foam heights lead, in cosmetic formulations for example, to creamy foams which are sensorily appealing.