WO1992001507A2

WO1992001507A2 - Fluid long-shelf-life dispersions of partial fatty acid glycerides

Info

Publication number: WO1992001507A2
Application number: PCT/EP1991/001335
Authority: WO
Inventors: Thomas Förster; Holger Tesmann; Soraya Shamsai; Michael Schaaf
Original assignee: Henkel Kommanditgesellschaft Auf Aktien
Priority date: 1990-07-25
Filing date: 1991-07-17
Publication date: 1992-02-06
Also published as: JPH05509087A; WO1992001507A3; DE4023600A1

Abstract

Disclosed are dispersions of partial fatty-acid glycerides containing: (A) 10-45 % by wt. of a partial fatty-acid glyceride, (B) 0.1-5 % by wt. of one or more non-ionic emulsifying agents with an HLB value of 12-19.8, (C) 40-89.7 % by wt. of water, and also containing: (D) 0.1-5 % by wt. of one or more water-insoluble oils and/or (E) 0.1-5 % by wt. of one or more alkali-metal or alkaline-earth salts of a low molecular-weight acid. Such dispersions have good flow properties and a long shelf life.

Description

"Flowable, stable dispersions of partial fatty acid fatty acids"

The invention relates to flowable and pumpable, storage-stable, aqueous dispersions of up to 45% by weight of fatty acid partial glycerides containing a nonionic dispersant and an additional content of a water-insoluble oil body and / or an electrolyte from the group at normal temperature the alkali or alkaline earth salts of low molecular acids.

It is known that fatty acid partial glycerides are used in the field of cosmetics as consistency agents for emulsions. Of particular importance is the glycerol mono- / distearate, hereinafter referred to as GMS for short. The incorporation of fatty substances such as GMS, which are solid, wax-like substances at normal temperature, requires melting and uniform, stable dispersion in the likewise heated solution or emulsion of the other components. When cooling, viscous lamellar gel phases form (compare, for example, K. Larsson, journal Physikalische Chemie 1967 (56) 173-198), which complicate the processing process. This mode of operation means a considerable amount of work, so that it would be advantageous for many users to already have fatty substances of the GMS type in the form of a stable, flowable dispersant concentrate. Such a concentrate may be homogeneous by merely mixing in elemental ^'way are entered in other aqueous formulations.

From the teaching of DE-PS 25 11 600 and DE-PS 25 11 644 a process for the production of emulsions is known which uses aqueous GMS dispersions. DE-AS 2509255 claims fatty acid mono- / diglycerides with a content of protein-fatty acid condensates to reduce the viscosity. According to the teaching of European patent EP 249711, low-viscosity aqueous dispersions of glycerol esters are prepared by adding defined amounts of alkali metal to the soap-free glycerol esters. long chain fatty acids can be added to soaps. However, the aqueous GMS dispersions of the prior art have the disadvantage of swelling to viscous gels in the course of storage.

The reason for the subsequent thickening is the gel formation, which is promoted by free fatty acids and dispersants. Depending on the content of free fatty acid, crystals or la ellar gel phases are formed (see: a) N.Krog and K.Larsson, Chem. Phys. Lipids 1968 (2) 129-143; b) K.Larsson and N.Krog, Chem. Phys. Lipids 1973 (10) 177-180; c) N.Krog and A.P. Borup, J. Sei. F Agric. 1973 (24) 691-701).

It has now been found that the tendency of GMS dispersions to thicken by a small addition of a water-insoluble oil body and / or an alkali metal or alkaline earth metal salt of a low molecular acid can be reduced, so that flowable, storage-stable GMS dispersions can be produced.

The invention consequently relates to dispersions of fatty acid partial glycerides containing

(A) 10-45% by weight, preferably 20-35% by weight, of a fatty acid partial glyceride,

(B) 0.1 to 5 percent by weight, preferably 0.2-2% by weight, of one or more nonionic surface-active ethylene oxide adducts with an HLB value of 12-19.6 as a dispersant and

(C) 40 to 89.7 weight percent water, characterized by an additional content of

(D) 0.1 to 5 weight percent, preferably 0.2 to 3 wt .-% of one or ^"meh¬ of exemplary water-insoluble oil components and / or

(E) 0.1 to 5% by weight, preferably 0.2-3% by weight, of one or more electrolytes from the group of the alkali metal or alkaline earth metal salts of a low molecular weight acid, in order thereby to ensure the flowability and the storage stability of the dispersion .

Fatty acid partial glycerides (A) of saturated or unsaturated fatty acids with 10 to 20 carbon atoms include technical mixtures of fatty acid mono-, di- and triglycerides which are obtained by esterification of 1 mole of glycerine with 1 to 2 moles of a (Cιo-2θ) ^"fre ^'ttsäure ° ^ ^it by transesterification of 1 mol of a (Cιo-2θ) ~ ^ce ^Fettsäuretr i9ly For example, beef tallow, lard, palm oil, sunflower oil or soybean oil with 0.5 to 2 moles of glycerin. Two types of partial glycerides are commercially available. Partial glycerides of type I contain 35 to 60% monoglycerides, 35 to 50% Diglycerides and 1 to 20% triglycerides Partial glycerides of type II are produced from those of type I by molecular distillation and contain 90 to 96% monoglycerides, 1 to 5% diglycerides and less than 1% triglycerides (see also: a) G Schuster and W. Adams: Zeitschrift für Lebensmitteltechnologie, 1979, Volume 30 (6), pp. 256-264; b) G. Schuster (ed.) "Emulsifiers for Food", Springer-Verlag, 1985) Fatty acid partial glycerides are said to be 35 to 96% monoglycerides, 1 to 50 % Diglycerides and 0.1 to 20% triglycerides ent.

Nonionic dispersants suitable as dispersants (B) are characterized by a lipophilic, preferably linear alkyl or acyl group and a hydrophilic group formed from low molecular weight glycol, glucose and polyol ethers.

Nonionic ethylene oxide adducts on fatty alcohol with 16-22 carbon atoms which are suitable as dispersants (B) are commercially available. The technical products are mixtures of homologous polyglycol ethers of the starting fatty alcohols, the average degree of oxyethylation of which corresponds to the molar amount of ethylene oxide added. Ethylene oxide addition products onto partial esters of a polyol with 3 - 6 C atoms and fatty acids with 14 - 22 C atoms can also be used as emulsifiers. Products of this type are produced, for example, by ethoxylating fatty acid partial glycerides or mono- and di-fatty acid esters of sorbitan, for example sorbitan monostearate or sorbitan sesquioleate. The emulsifiers suitable for the process according to the invention should have an HLB value of 12-19.6. The HLB value (hydrophile-lipophile balance) is to be understood as a value which can be calculated in accordance with - 4 -

HLB - 100 - 5

where L is the weight fraction of the lipophilic groups, i.e. of the fatty alkyl or fatty acyl groups in percent by weight in the ethylene oxide adducts.

Preferred dispersants (B) are fatty alcohol polyglycol ethers of the general formula

(I) R ¹ - (0-CH2-CH2) _n -0H

in which R * is a saturated or unsaturated, straight-chain or branched hydrocarbon radical having 8 to 22 carbon atoms, preferably 12 to 18 carbon atoms and n an integer from 10 to 150, preferably from 20 to 80, and addition products of 4 to 40 moles of ethylene oxide to one or more of the fatty acid partial glycerides (A) according to the invention.

The oil body (D) used can be any hydrocarbon, ether or ester which is liquid, water-insoluble, branched or linear and physiologically compatible at room temperature (20 ° C.). However, solid or higher-melting paraffins, esters, waxes or fats can also be used in such quantities that the mixture with the liquid oil components remains liquid at 20.degree.

Paraffin oils and synthetic hydrocarbons, e.g. liquid polyolefins or defined hydrocarbons, e.g. Alkylcyclohexanes such as e.g. 1,3-diisooctylcyclohexane.

However, mono- and diesters of the formulas are also suitable

(II) R2-C00R3

(III) R3-00C-R -C00R3

(IV) R2-C00-R4-00C-R2 wherein R ² and R ^{3 are} alkyl groups with 1 to 22 carbon atoms or alkenyl groups with 8 to 22 carbon atoms and R ^{4 are} alkylene groups with 2 to 16 carbon atoms and which contain at least 10 carbon atoms.

Oil bodies of the type of the mono- and diesters of the formulas (II), (III) and (IV) are known as cosmetic and pharmaceutical oil components and as lubricants and lubricants. Among the mono- and diesters of this type, the products that are liquid at room temperature (20 ° C) are of the greatest importance. Suitable monoesters (II) as oil bodies are e.g. the methyl esters and isopropyl esters of fatty acids with 12-22 carbon atoms, such as Methyl laurate, methyl stearate, methyl oleate, methyl erucate, isopropyl myristate, isopropyl pal itate, isopropyl stearate, isopropyl oleate. Other suitable monoesters are e.g. n-butyl stearate, n-hexyl laurate, n-decyl oleate, isooctyl stearate, isononyl palmitate, isononyl isononanoate, 2-ethylhexyl palmitate, 2-ethylhexyl laurate, 2-hexyldecyl stearate, 2-octyldodecyl palmitate Oleylerucate, erucyl oleate and esters which are obtainable from technical aliphatic alcohol mixtures and technical aliphatic carboxylic acids, for example Esters from saturated and unsaturated fatty alcohols with 12 - 22 C atoms and saturated and unsaturated fatty acids with 12 - 22 C atoms, as can be obtained from animal and vegetable fats. Naturally occurring monoester or wax ester mixtures, such as those e.g. present in jojoba oil or in spar oil.

Suitable dicarboxylic acid esters (III) are e.g. Di-n-butyl adipate, di-n-butyl sebacate, di- (2-ethylhexyl) adipate, di- (2-hexyldecyl) succinate and diisotridecyl acelaate. Suitable diol esters (IV) are e.g. Ethylene glycol dioleate, ethylene glycol di-isotridecanoate, propylene glycol di- (2-ethylhexanoate), butanediol di-isostearate and neopentyl glycol di-caprylate.

All readily water-soluble alkali metal or alkaline earth metal salts of low molecular weight acids and / or their hydrates can be used as electrolyte (E). The following are considered as low molecular weight acids: the mineral acids hydrochloric, sulfuric, nitric and phosphoric acids, furthermore hydrofluoric acid, hydrobromic acid, hydroiodic acid, sulfurous acid right, nitrous acid, phosphonic acid, boric acid or carboxylic acids with 1 to 8 carbon atoms, for example formic acid, acetic acid, propionic acid, citric acid, malic acid, lactic acid, oxalic acid, benzoic acid.

The dispersions according to the invention can be prepared in a simple manner by combining all components of the dispersion to be prepared at normal temperature (approx. 20 ° C.) and heating to 80 ° C. with stirring. After the solid constituents have melted, the mixture is left to stir for a few minutes and the dispersions thus obtained are then cooled to normal temperature.

The following examples are intended to explain the subject matter of the invention in more detail without restricting it thereto.

B e i s p i e l e

1. Substances used

1.1. Fatty acid mono-Zdiolvceride (A)

The glycerol mono- / distearate, GMS, used as an example consisted of a technical partial glyceride, of a palmitin-stearic acid mixture (30:70) with a proportion of 50 wt.% Monoglyceride, 40 wt. % Triglyceride.

1.2. Dispersants (B)

TA 67 = adduct of 67 moles of ethylene oxide

Cetyl stearyl alcohol (weight ratio 30:70)

TA 120 = adduct of 120 moles of ethylene oxide

Cetyl stearyl alcohol (weight ratio 30:70)

Tagat S = adduct of 30 moles of ethylene oxide

Glycerol mono- / distearate (weight ratio 30:70)

1.3. oil body (D)

Paraffin oil = thick paraffin oil (DAB 8), Vaseline-Fabrik Rhenania Wasserfuhr GmbH, Bonn

2. Preparation and characterization of the dispersions

All components of the dispersion to be prepared were combined at normal temperature and heated to 70 to 80 ° C. with stirring. After all the solid had melted, stirring was continued for a few minutes. The dispersions thus obtained were then rapidly cooled to + 20 ° C. The dispersions were stored at normal temperature for 30 days. The viscosity was then measured at + 20 ° C. using a CARRIMED CS 200 rotary rheometer with plate-plate arrangement at a shear rate of 30 s ~ l. The yield point was also determined.

The composition of the dispersions and their yield point and viscosity are summarized in Table 1. Example 2-1 represents a comparative example which contains no proportion of an oil component (D) or contains an electrolyte (E). In contrast, Examples 2-2 to 2-9 show the advantages of the dispersions according to the invention; the effect of a drastic reduction in the yield point and viscosity in comparison to Example 2-1 in Examples 2-3 and 2-5 is particularly impressive. Examples 2-10 and 2-11 also show that the advantages of the dispersions according to the invention are retained even after a very long storage time - here after 115 days.

Table 1: Composition in% by weight, viscosity and yield point of the dispersions according to Example 2

Feature component 2-1 2-2 2-3 2-4 2-5 2-6 2-7 2-8 2-9 2-10 ¹ ) 2-lll)

A GMS 30 30 30 30 30 30 30 30 30 30 30

B TA 20 - - - - - - - - - - -

B TA 67 0.2 0.2 0.2 0.2 0.2 0.2

B TA 120 - - - - - - - 0.2 0.2

B Tagat S - - - - - 1.5 1.5 - - - -

C water 69.8 69.3 69.3 68.8 68.5 67.5 68.0 68.9 69.3 69.3 68.8

D Paraffin oil - - - 1.0 - 1.0 - 1.0 - - 1.0

E CaCl2 - - 0.5 - - - 0.5 0.5 0.5

E NaCl _ o, 5 - - - - - - - - -

1) Storage time of the dispersion: 115 days

2) Viscosity (Pa-s)

3) Yield point (Pa)

Claims

Patent claims

1. Containing dispersions of fatty acid partial glycerides

(B) 0.1 to 5 percent by weight, preferably 0.2-2% by weight, of one or more nonionic surface-active ethylene oxide addition products with an HLB value of 12-19.6 as a dispersant and

(C) 40 to 89.7 weight percent water, characterized by an additional content of

(D) 0.1 to 5% by weight, preferably 0.2-3% by weight, of one or more water-insoluble oil bodies and / or

(E) 0.1 to 5% by weight, preferably 0.2-3% by weight, of one or more electrolytes from the group of the alkali metal or alkaline earth metal salts of a low molecular weight acid, in order to improve the flowability and the storage stability of the dispersion .

2. Dispersions according to claim 1, characterized in that it is the nonionic surface-active ethylene oxide addition product (B) is a fatty alcohol polyglycol ether of the general formula

(I) R ¹ - (0-CH ₂ -CH ₂ ) _n -0H

is where R is a saturated or unsaturated, straight-chain or branched hydrocarbon radical having 8-22 carbon atoms, preferably 12-18 carbon atoms and n is an integer from 10 to 150, preferably 20 to 80.

3. Dispersions according to claim 1, characterized in that the nonionic surface-active ethylene oxide adduct (B) is an additive of 8 to 40 moles of ethylene oxide to a fatty acid partial glyceride (A) of saturated or unsaturated fatty acids having 10 to 20 carbon atoms is.

4. Dispersions according to one of claims 1 to 3, characterized in that the water-insoluble oil body (D) is a paraffin oil.

5. Dispersions according to one of claims 1 to 3, characterized in that the water-insoluble oil body (D) is a mono- and / or diester of the general formula (II), (III) or (IV),

(II) R ² -C00R3

(III) R3-00C-R -C00R ³

(IV) R2-C00-R ⁴ -00C-R ²

wherein R2 and R3 are alkyl groups with 1 to 22 carbon atoms or alkenyl groups with 8 to 22 carbon atoms and R ^{4 is} alkylene groups with 2 to 16 carbon atoms and which contain at least 10 carbon atoms.

6. Dispersion according to one of claims 1 to 4, characterized in that the electrolyte (E) is an alkaline earth metal salt of a low molecular weight acid.

7. Dispersion according to one of claims 1 to 5, characterized in that the electrolyte (E) is the salt of a mineral acid.

8. Use of the dispersions according to one of claims 1 to 7 for the manufacture of emulsions for use e.g. in the field of cosmetics or in the paper industry.