Use of isosorbide monoesters as thickeners

Abstract

The use of one or more compounds of the formula (I) ##STR00001## in which R is a straight-chain or branched saturated alkyl group having 5 to 11 carbon atoms or a straight-chain or branched mono- or polyunsaturated alkenyl group having 5 to 11 carbon atoms
as thickeners is described. The use is preferably in cosmetic, dermatological or pharmaceutical compositions, in crop protection formulations, in washing or cleaning compositions or in paints or coatings.

Claims

1. A method of thickening a cosmetic, dermatological or pharmaceutical composition, crop protection formulation, washing or cleaning composition or paint or coating, comprising the step of adding a thickening composition comprising at least one compound of the formula (I) ##STR00005## in which R is a straight-chain or branched saturated alkyl group having 5 to 11 carbon atoms or a straight-chain or branched mono- or polyunsaturated alkenyl group having 5 to 11 carbon atoms, wherein the thickening composition further comprises at least one other substance selected from the group consisting of sorbitol, sorbitol esters, isosorbide, isosorbide diesters and carboxylic acids and wherein the hydroxyl value of the mixture of the at least one compound of the formula (I) and the at least one other substance selected from the group consisting of sorbitol, sorbitol esters, isosorbide, isosorbide diesters and carboxylic acids is less than or equal to 320, to the cosmetic, dermatological or pharmaceutical composition, crop protection formulation, washing or cleaning composition or paint or coating.

2. The method of claim 1, wherein the radical R in formula (I) is a straight-chain saturated alkyl radical having 7 to 9 carbon atoms.

3. The method of claim 2, wherein the radical R in formula (I) is a straight-chain saturated alkyl radical having 7 carbon atoms.

4. The method of claim 1, wherein the thickening composition comprises at least one compound of the formula (I), I) isosorbide and II) at least one isosorbide diester of the formula (II) ##STR00006## where R is a straight-chain or branched saturated alkyl group having 5 to 11 carbon atoms or a straight-chain or branched mono- or polyunsaturated alkenyl group having 5 to 11 carbon atoms.

5. The method of claim 4, wherein the thickening composition comprises at least one compound of the formula (I), I) from 0.05 to 0.7 by weight of isosorbide and II) from 0.1 to 1.0 by weight of the at least one isosorbide diester of the formula (II), in each case based on 1.0 part by weight of the at least one compound of the formula (I).

6. The method of claim 1, wherein the thickening composition comprises the at least one compound of the formula (I) in an amount of at least 30% by weight, in each case based on the total weight of the finished composition.

7. The method of claim 1, wherein the cosmetic, dermatological or pharmaceutical composition, the crop protection formulation, the washing or cleaning composition or the paint or coating comprises the at least one compound of the formula (I) in an amount of from 0.01 to 10.0% by weight, in each case based on the total weight of the finished cosmetic, dermatological or pharmaceutical composition, crop protection formulation, washing or cleaning composition or paint or coating.

8. The method of claim 1, wherein the cosmetic, dermatological or pharmaceutical composition, the crop protection formulation, the washing or cleaning composition or the paint or coating are formulated on an aqueous or aqueous-alcoholic basis or are present as emulsion or dispersion.

9. The method of claim 1, wherein the cosmetic, dermatological or pharmaceutical composition, the crop protection formulation, the washing or cleaning composition or the paint or coating have a pH of from 2 to 11.

Description

EXPERIMENTAL EXAMPLES

A) Preparation of Isosorbide Caprylate

(1) In a stirred apparatus with distillation head, 190.0 g (1.3 mol) of isosorbide (Sorbon from Ecogreen Oleochemicals) and 187.5 g (1.3 mol) of octanoic acid (caprylic acid) are initially charged at 80 C. together with 0.38 g of aqueous sodium hydroxide solution (18% by weight strength, aqueous) as catalyst. With stirring and under a flow of nitrogen (10-12 liters per hour), the reaction mixture is initially heated to 180 C., where the water of reaction begins to distill off. The reaction mixture is then heated to 190 C. over a period of 1 hour and to 210 C. over a further 2 hours. After 210 C. is reached, the esterification is continued until an acid value of <1 mg KOH/g is reached. This gives 345.7 g of amber isosorbide caprylate (97% of theory). The pH (5% by weight in ethanol/water 1:1) is 5.9. The pH was measured according to DIN EN 1262.

(2) Further analytical characteristics of the isosorbide caprylate: Acid value: 0.9 mg KOH/g, measured according to DIN EN ISO 2114 Hydroxyl value: 206 mg KOH/g, measured analogously to DIN 53240-2 according to method OHV-A Saponification value: 204 mg KOH/g, measured according to DIN EN ISO 3681

(3) The isosorbide caprylate has the following composition:

(4) TABLE-US-00001 Substance % by weight caprylic acid 0.4 isosorbide 18.1 isosorbide monocaprylate 50.9 isosorbide dicaprylate 30.6

(5) Hereinbelow, this composition is referred to as isosorbide caprylate 1

B) Determination of the Thickener Performance of Isosorbide Caprylate 1

(6) Using Genapol LRO (sodium laureth-2 sulfate, 27% by weight in water) and Genagen CAB 818 (cocamidopropyl betaine, 30% by weight in water) and additionally water, a 15% by weight mixture in water comprising the two surfactants in a weight ratio of 8:2 (hereinbelow referred to as mixture 1) is obtained. Various substances were added to this mixture 1, and the viscosity of the resulting compositions was determined. The results are shown in table 1 below.

(7) TABLE-US-00002 TABLE 1 measured viscosities Added substance; amount Viscosity [% by weight] [mPa .Math. s] NaCl [0.5% by weight] 40 NaCl [0.5% by weight] and isosorbide caprylate 1 [1% 330 by weight]

(8) Various amounts of isosorbide caprylate 1 were added to mixture 1, and the viscosity of the resulting compositions was determined. The results are shown in table 2 below.

(9) TABLE-US-00003 TABLE 2 measured viscosities Amount of isosorbide caprylate 1 added Viscosity [% by weight] [mPa .Math. s] 0 5 0.2 6 0.4 10 0.6 12 0.8 21 1.0 12 1.2 37 1.4 34 1.6 45 1.8 55 2.0 72

(10) It is evident from the results listed in tables 1 and 2 that isosorbide caprylate 1 has a thickening effect in aqueous surfactant systems.

C) Determination of the Thickener Performance of Isosorbide Caprylate 1

(11) Using Genapol LRO (sodium laureth-2 sulfate, 27% by weight in water) and Genagen KB (cocobetain, 30% by weight in water) and additionally water, a 15% by weight mixture in water comprising the two surfactants in a weight ratio of 8:2 (hereinbelow referred to as mixture 2) is obtained. Various substances were added to this mixture 2, and the viscosity of the resulting compositions was determined. The results are shown in table 3 below.

(12) TABLE-US-00004 TABLE 3 measured viscosities Added substance; amount Viscosity [% by weight] [mPa .Math. s] NaCl [0.5% by weight] 3830 NaCl [0.5% by weight] and isosorbide caprylate 1 [1% 14200 by weight]

(13) Various amounts of isosorbide caprylate 1 were added to mixture 2, and the viscosity of the resulting compositions was determined. The results are shown in table 4 below.

(14) TABLE-US-00005 TABLE 4 measured viscosities Amount of isosorbide caprylate 1 added Viscosity [% by weight] [mPa .Math. s] 0 135 0.2 310 0.4 460 0.6 875 0.8 1550 1.0 2510 1.2 4190 1.4 5650 1.6 6600 1.8 7400 2.0 7050

(15) It is evident from the results listed in tables 3 and 4 that isosorbide caprylate 1 has a thickening effect in aqueous surfactant systems.

D) Determination of the Thickener Performance of Isosorbide Caprylate 1

(16) An emulsion as indicated in table 5 below was prepared, and various concentrations of isosorbide caprylate 1 were added. The viscosities of the resulting emulsions were determined. The results are shown in table 5 below.

(17) TABLE-US-00006 TABLE 5 measured viscosities Composition 1 2 3 4 Hostaphat KL 340 D (A) 1 1 1 1 trilaureth-4 phosphate mineral oil n.v. (A) 8 8 8 8 isopropyl palmitate (A) 3 3 3 3 Lanette O (A) 0.5 0.5 0.5 0.5 cetearyl alcohol Myritol 318 (A) 2 2 2 2 caprylic/capric triglyceride Tegin M (A) 0.5 0.5 0.5 0.5 glyceryl stearate isosorbide caprylate 1 (A) 0.5 1.0 1.5 Aristoflex AVC (B) 0.4 0.4 0.4 0.4 ammonium acryloyldimethyltaurate/VP copolymer water (C) 71.6 72.1 71.6 71.1 glycerol (C) 5 5 5 5 alcohol (D) 5 5 5 5 tocopheryl acetate (D) 1 1 1 1 SilCare Silicone 41M15 (D) 1 1 1 1 caprylyl methicone Nipaguard PDU (E) 1 1 1 1 diazolidinylurea, methylparaben, propylparaben, propylene glycol pH measured 6.34 6.21 6.12 6.20 viscosity [mPa .Math. s] 1860 2260 3130 3200

(18) Preparation: I The components of A are mixed and the mixture is heated to 60 C. II The components of C are mixed and the mixture is heated to 60 C. III B is added to I IV II is added to III and the mixture is stirred until it has cooled to room temperature V The components D are gradually added to IV VI E is added to V, and the emulsion is homogenized

(19) It is evident from the results listed in table 5 that isosorbide caprylate 1 has a thickening effect in emulsions.

E) Comparative Experiment

(20) The thickener performance of isosorbide caprylate 1 in mixture 2 was compared, firstly, to a composition comprising 89.6% by weight of isosorbide dicaprylate and 9.4% by weight of isosorbide monocaprylate (remainder: 1% by weight) (hereinbelow referred to as isosorbide dicaprylate) and, secondly, to pure isosorbide. The results are shown in table 6.

(21) TABLE-US-00007 TABLE 6 measured viscosities Substance added to mixture 2; amount Viscosity [% by weight] [mPa .Math. s] none 135 isosorbide caprylate 1 [1% by weight] 2510 isosorbide dicaprylate [1% by weight] 2390 isosorbide [1% by weight] 160

(22) As is evident from the results of table 6, the thickener performance of isosorbide is not worth mentioning, whereas isosorbide dicaprylate causes significant thickening.

(23) However, as is also evident from the results of table 6, isosorbide caprylate 1 causes thickening comparable to that of isosorbide dicaprylate. If the thickener performance of isosorbide caprylate 1 were due only to the isosorbide dicaprylate comprised therein, the viscosity when using isosorbide caprylate 1 would have to be markedly lower that when isosorbide dicaprylate is used, since isosorbide caprylate 1 comprises only 30.6% by weight of isosorbide dicaprylate. Since the thickener performance of the isosorbide present in isosorbide caprylate 1 (as already mentioned above) is not worth mentioning and the possible thickening by the caprylic acid present in isosorbide caprylate 1 is negligible because of its small amount, but the thickener performance of isosorbide caprylate 1 is nevertheless comparable to the thickener performance of isosorbide dicaprylate, the compound isosorbide monocaprylate present in isosorbide caprylate 1 must have a significant thickener performance.

F) Use Examples

(24) The use according to the invention can take place, for example, in the following formulations.

Formulation Example 1

Very Gentle EO- and Sulfate-Free Shampoo

(25) TABLE-US-00008 % by Phase Ingredient weight A water ad 100 B sorbitol 1.0 C Hostapon SG 30.0 sodium cocoyl glycinate 15.0 Genagen KB coco-betaine Plantacare 818 UP 9.23 coco glucoside isosorbide caprylate 1 1.0 D lactic acid 25% by weight strength in water 3.25 E preservative q.s.

(26) Preparation: I B is added to A and the mixture is stirred until a clear solution is obtained II C is added to I and the mixture is stirred until the solution is homogeneous III The pH is adjusted to 7.0-7.2 using D IV E is added to III

Formulation Example 2

Gentle Facial Cleanser

(27) TABLE-US-00009 % by Phase Ingredient weight A water ad 100 glycerol 20.0 B Hostapon SG 34.0 sodium cocoyl glycinate lauric acid 1.0 myristic acid 0.25 stearic acid 0.25 isosorbide caprylate 1 1.0 C lactic acid 0.90 water 6.80 D Genagen CAB 10.0 cocamidopropyl betaine E preservative q.s. fragrance q.s.

(28) Preparation: I Phase A is mixed and heated to 80 C. II The components of B are added gradually to I and stirring is continued at 80 C. III Phase C is mixed and added to II IV The mixture is allowed to cool to 60 C., and D is added to III V At 40 C., E is added to IV

Formulation Example 3

Dishwashing Liquids

(29) TABLE-US-00010 Ingredient % by weight Hostapur SAS 60 40.0 (alkanesulfonate, 60% by weight in water) Hostapur OS liquid 11.0 (sodium C14-16 alkyl sulfonate, 40% by weight in water) isosorbide caprylate 1 1.0 Genagen CAB 3.0 (cocoamidopropyl betaine, 30% by weight in water) preservative q.s. water ad 100

Formulation Example 4

Surface Cleaners (all-Purpose Cleaners)

(30) TABLE-US-00011 Ingredient % by weight Hostapur SAS 60 5.0 (alkanesulfonate, 60% by weight in water) Genapol UD 080 2.0 (undecanol + 8 EO) isosorbide caprylate 1 1.0 preservative q.s. water ad 100

(31) Preparation of formulation examples 3 and 4:

(32) Half of the amount of water is initially charged and the components are stirred in in the same order as listed in the tables. The remaining amount of water is then added. This gives clear aqueous compositions.