Oil-in-water emulsions

Abstract

The invention relates to oil-in-water emulsions based on fatty alcohols and mono- or diesters of glycerol and the use thereof as antifoams or deaerators for aqueous compositions. The oil phase of the emulsions according to the invention consists to at least 95% by weight of the following constituents: a) 40 to 95% by weight, based on the total weight of the oil phase, of a mixture of at least two alcohols as component A, consisting of: a1) at least one alkanol having 12 to 30 carbon atoms as component A1, a2) at least one mono- or diester of glycerol with at least one fatty acid having 14 to 24 carbon atoms as component A2; b) 0.1 to 10% by weight, based on the total weight of the oil phase, of at least one further component B, which is selected from esters of C.sub.12-C.sub.36-alkanecarboxylic acids with polyglycerol, amides of C.sub.12-C.sub.36-alkanecarboxylic acids with alkylenediamines or oligoalkyleneamines, and esters of C.sub.12-C.sub.36-alkanecarboxylic acids with C.sub.12-C.sub.36-alkanols, and mixtures thereof, c) 4.9 to 50% by weight, based on the total weight of the oil phase, of at least one further component C, which is selected from organic substances which are liquid at 50 C. and 1013 mbar, at atmospheric pressure have a boiling point above 200 C., and at 25 C. and 1013 mbar have a solubility in water of less than 0.1 g/l.

Claims

1. An oil-in-water emulsion comprising: an aqueous phase and an oil phase, wherein the oil phase comprises at least 95% by weight of components A, B and C: A) from 40 to 95% by weight, based on a total weight of the oil phase, of a mixture comprising: A1) an alkanol having 12 to 30 carbon atoms, and A2) a mono- or diester of glycerol with at least one fatty acid having 14 to 22 carbon atoms; comprising at least 80% by weight, based on a total weight of component A2, of a mono- or diester of glycerol with at least one linear C.sub.16-C.sub.22-alkanecarboxylic acid, wherein a weight ratio of the alkanol to the mono- or diester of glycerol with at least one fatty acid having 14 to 22 carbon atoms is of from 1:3 to 3:1; B) from 0.1 to 10% by weight, based on the total weight of the oil phase, of a component, which is at least one selected from the group consisting of an ester of a C.sub.12-C.sub.36-alkanecarboxylic acid with polyglycerol, an amide of a C.sub.12-C.sub.36-alkanecarboxylic acid with an alkylenediamine or an oligoalkyleneamine, and an ester of a C.sub.12-C.sub.36-alkanecarboxylic acid with a C.sub.12-C.sub.36-alkanol, C) from 4.9 to 50% by weight, based on the total weight of the oil phase, of an organic substance other than component A, wherein the organic substance is liquid at 50 C. and 1013 mbar, at atmospheric pressure, the organic substance has a boiling point above 200 C., and at 25 C. and 1013 mbar, the organic substance has a solubility in water of less than 0.1 g/l.

2. The oil-in-water emulsion according to claim 1, wherein component A1) comprises at least 80% by weight of a linear alkanol having 16 to 26 carbon atoms.

3. The oil-in-water emulsion according to claim 1, wherein the component B comprises at least 80% by weight, based on a total weight of component B, of an ester of at least one C.sub.18-C.sub.24-alkanecarboxylic acid with polyglycerol.

4. The oil-in-water emulsion according to claim 3, wherein the ester of at least one C.sub.18-C.sub.24-alkanecarboxylic acid with polyglycerol is obtained by esterification of polyglycerol with behenic acid.

5. The oil-in-water emulsion according to claim 1, wherein the organic substance comprises at least 80% by weight, based on a total weight of component C, of an aliphatic hydrocarbon oil.

6. The oil-in-water emulsion according to claim 1, wherein a solids content of the oil-in-water emulsion is of from 10 to 50%, based on a total weight of said emulsion.

7. The oil-in-water emulsion according to claim 1, a weight-average particle size of oil droplets of the oil-in-water emulsion is of from 0.5 to 10 m.

8. A method for reducing foam or air in a composition, the method comprising: adding the oil-in-water emulsion according to claim 1 to a composition.

9. The method according to claim 8, wherein said oil-in-water emulsion is added to said composition at a temperature of from 20 to 50 C.

10. A method for deaerating an aqueous paper stock suspension, the method comprising: adding the oil-in-water emulsion according to claim 1 to an aqueous paper stock suspension.

11. A method for deaerating a headbox in papermaking, the method comprising: adding the oil-in-water emulsion according to claim 1 to a headbox in papermaking.

12. An oil-in-water emulsion comprising: an aqueous phase and an oil phase, wherein the oil phase comprises at least 95% by weight of components A, B and C: A) from 40 to 95% by weight, based on a total weight of the oil phase, of a mixture comprising: A1) an alkanol having 12 to 30 carbon atoms, comprising at least 80% by weight of a linear alkanol having 16 to 26 carbon atoms, and A2) a mono- or diester of glycerol with at least one fatty acid having 14 to 22 carbon atoms; comprising at least 80% by weight, based on a total weight of component A2, of a mono- or diester of glycerol with at least one linear C.sub.16-C.sub.22-alkanecarboxylic acid, wherein a weight ratio of the alkanol to the mono- or diester of glycerol with at least one fatty acid having 14 to 22 carbon atoms is of from 1:3 to 3:1; B) from 0.1 to 10% by weight, based on the total weight of the oil phase, of a component, which is at least one selected from the group consisting of an ester of a C.sub.12-C.sub.36-alkanecarboxylic acid with polyglycerol, an amide of a C.sub.12-C.sub.36-alkanecarboxylic acid with an alkylenediamine or an oligoalkyleneamine, and an ester of a C.sub.12-C.sub.36-alkanecarboxylic acid with a C.sub.12-C.sub.36-alkanol, C) from 4.9 to 50% by weight, based on the total weight of the oil phase, of an organic substance other than component A, wherein the organic substance is liquid at 50 C. and 1013 mbar, at atmospheric pressure, the organic substance has a boiling point above 200 C., and at 25 C. and 1013 mbar, the organic substance has a solubility in water of less than 0.1 g/l, wherein a fraction of A1 and A2 in said oil phase is 50 to 80% by weight, and component B comprises at least 80% by weight, based on a total weight of component B, of an ester of at least one C.sub.18-C.sub.24-alkanecarboxylic acid with polyglycerol.

13. The oil-in-water emulsion according to claim 12, wherein the organic substance comprises at least 80% by weight, based on a total weight of component C, of an aliphatic hydrocarbon oil.

14. The oil-in-water emulsion according to claim 13, wherein said aliphatic hydrocarbon oil is at least one oil selected from the group consisting of a vegetable oil and an animal oil.

Description

EXAMPLE 1

(1) The components of the oil phase were firstly heated to a temperature of 100 to 110 C. and then incorporated into the aqueous phase heated to 80 C. to 95 C. by means of a dispersing device and then cooled to 25 C. with an ice bath. The resulting emulsion was then filtered.

(2) The oil phase had the following composition, based on the total weight of the emulsion: 9.2 parts of the C.sub.20+-fatty alcohol mixture, 9.2 parts of glycerol distearate 7.3 parts of rapeseed oil, 1.6 parts of polyglycerol ester, 0.1 part of formaldehyde (30% strength) 0.1 part of Proxel.

(3) The water phase consisted, based on the total weight of the emulsion, of: 46.9 parts of water, 25 parts of xanthan (1% strength), 0.6 part of the emulsifier Emulan TO 4070 (70% strength)

(4) The examples and comparative examples given in table 1 were prepared in an analogous manner. The quantitative data are % by weight, based on the total weight of the emulsion. The composition of the water phase corresponded in all examples to the water phase of example 1. The physical properties and the deaerating effect of this emulsion are given in table 2.

(5) TABLE-US-00001 TABLE 1 Composition of the examples and comparative examples Example Component 1 2 3 C1 C2 C3 C.sub.20+-Fatty alcohol 9.2 9.2 9.2 18.4 mixture Glycerol stearate 1 9.2 18.4 Glycerol stearate 2 9.2 9.2 18.4 Polyglycerol ester 1.6 1.6 1.6 1.6 1.6 1.6 Emulsifier Rapeseed oil 7.3 7.3 7.3 7.3 7.3 Palm oil 7.3 Biocides 0.2 0.2 0.2 0.2 0.2 0.2 Water 46.9 46.9 46.9 46.9 46.9 46.9

(6) TABLE-US-00002 TABLE 2 Physical properties and deaerating effect of the antifoams Average particle Viscosity Solids content Air content [%] size (d.sub.50) [m] pH [mPas] [%] 40 C. 1 2.3 7.3 1200 28.9 0.21 2 3.2 6.4 2320 27.7 0.23 3 3.2 6.5 2360 28.1 0.28 C1 2.8 7.1 630 28.0 0.60 C2 3.7 7.1 1130 28.7 0.76 C3 2.7 6.3 3330 27.9 0.79