GB2315757A

GB2315757A - Dilution stable antifoam emulsion concentrate

Info

Publication number: GB2315757A
Application number: GB9714961A
Authority: GB
Inventors: Wen P Liao; Adam J Horne
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1996-07-31
Filing date: 1997-07-16
Publication date: 1998-02-11
Anticipated expiration: 2017-07-16
Also published as: FR2751889A1; GB9714961D0; JPH10113552A; DE19731615B4; GB2315757B; FR2751889B1; DE19731615A1

Abstract

A water-in-oil emulsion comprising a silicone oil (preferably a polydimethylsiloxane), silica, emulsifiers, and thickening agents having the property that upon dilution the emulsion inverts to an oil-in-Water emulsion useful as an antifoam agent. The emulsifier has an HLB of between 2 and 20 and is preferably an ester of oleic acid, especially an ester derived from glycerin.

Description

2315757 60SI-1843 - 1 DILLMON STABLE ANTIFOAM EMULSION CONCENTRATES The

present invention relates to an antifoarn concentrate that is a waterin-oil emulsion when concentrated but when diluted inverts and forms an oil-in-water emulsion that continues to function as an antifoam.

Backglound of the Invention Antifoam compositions are materials that when added to a foaming liquid equilibrate or accelerate the rate of foam collapse relative to the rate of foam formation. Usually such materials are added in small concentrations. Antifoaming agents have found application in a wide variety of manufacturing and treating processes, e.g. paints and lateces, coating processes, textiles, fermentation processes, polymer manufacture, ' cleaning compounds, pulp and paper, waste water treatment, and cooling towers.

It is generally a desired characteristic that antifoam agents be inert to the product or system in which it is used, i.e. that it have no adverse effect. The components of an antifbam composition generally consist of primary and secondary antifoam agents, a carrier, an emulsifier, and if desired a stabilizing agent The primary antifoam agent is usually a hydrophobic silica dispersed in an oil such as a hydrocarbon wax, a fatty acid, fatty acid ester, or fatty acid amide. It is the combination of the two ingredients that produces the antifoam action because hydrophobic silica by itself is inactive for collapsing foams. The secondary antifoam is usually a silicone or fatty alcohol or ester which increases the antifoarn effect of the primary antifoam 60SI-1843 2 agent. Carriers that are typically employed include hydrocarbon oils and solvents, water, and fatty alcohols or esters. Emulsifiers function to introduce the primary and secondary antifoam agents into the system being treated.

There are two basic types of antifoam compositions that comprise silicone compounds. The first type is a composition that utilizes materials that have a particular lower critical solubility temperature such as silicone polyethers. The mode of use of such materials involves using the composition at a temperature above its lower critical solubility temperature which is a temperature range where the material loses its solubility in water and therefore functions as an antifoaming agent Because of the restriction on the lower critical solubility temperature, these types of antifoarn compositions possess only limited utility because they function only within a narrow temperature range.

U. S. patent 5,106,535 teaches a silicone based defoaming composition that comprises a polyoxyalkylene substituted organopolysiloxane, a dimethyl silicone fluid and a finely divided silica. powder. In order to function as a defoaming agent the composition of the '535 patent requires a surface active agent for dispersal in aqueous systems to control foaming. The requirement that a surface active agent is necessary for dispersal of the defoarning composition has been modified by the incorporation of a second polyoxyalkylene modified silicone into the composition as taught in U. S. patent 5,244,599 which acts as a surface active agent U. S. patent 5,169,561 describes an unusual antifoam concentrate where the finely divided silica has been chemically treated with an anti- microbial agent to render the composition resistant to bacterial spoilage.

The second and more traditional type of antifoarn composition is an oilin-water emulsion prepared by emulsifying a silicone polymer and finely divided silica. While these types of emulsions are generally very effective as antifoarn agents they are not stable to dilution. Because such oil-in-water 60SI-1843 3 emulsions that function as antifoaming agents are thermodynamically unstable, thickening agents to increase the viscosity of the aqueous phase are added to retard the particle settling rate which increases the shelf stability of the emulsion. When these emulsions are diluted with water, the viscosity is reduced by the dilution and the emulsion becomes unstable.

There is thus a need for a traditional antifoarning agent that can be diluted into a wide range of concentrations and remain effective as an antifoaming agent Summaly of the Invention We now disclose a water-in-oil emulsion that functions as an antifoarn agent and, when diluted, inverts to an oil-in-water emulsion that continues to function as an antifoaming agent through a wide range of concentrations.

Thus the present invention provides for a water-in-oil emulsion comprising:

(a) from about 1 to about 99 percent by weight of a is polyorganosiloxane of the general formula IVIRM where M = R1R2R3Si0112 where R', R2P and R3 are each independently selected monovalent one to forty carbon atom hydrocarbon radicals where D = R4R555i02/2 where R4 and R5 are each independently selected monovalent one to forty carbon atom hydrocarbon radicals, with the stoichiometric subscript, x, ranging from about 1 to about 10,000 wherein the viscosity of the polyorganosiloxane ranges from about 1 to about 10,000, 900 centipoise at 25 oC; (b) from about 0.01 to about 50.0 percent by weight of a finely divided silica having a size ranging from about 0.001 to about 1,000 microns average particle diameter; 60SI-1843 4 (c) from about 0.10 to about 50.0 percent by weight of an emulsifier or mixture of emulsifiers having on average a hydrophilic lipophilic balance ratio ranging from about 2 to about 20; and (d) from about 0.001 to about 20.0 percent by weight of a thickening agent or mixture of a water soluble thickening agent selected from the group consisting of polyacrylates, polyamides, polyamines, styrene sulfonate polymers, polyethylene oxides and cellulose derivatives having a molecular weight ranging from about 100 to about 100,000,00 dalton; and (e) from slightly greater than 0 to about 20.0 percent by weight of water; wherein when said water-in-oil emulsion is added to a quantity of water greater in weight than the weight of said water-in-oil emulsion said emulsion inverts to an oil-in-water emulsion wherein said oil-in- water emulsion reduces foaming.

The present invention also provides for a method of reducing foaming is comprising:

(a) preparing a water-in-oil emulsion comprising:

(i) from about 1 to about 99 percent by weight of a polyorganosiloxane of the general formula MD.M where M = R1R2R3SiOi12 where R', R2, and R3 are each independently selected monovalent one to forty carbon atom hydrocarbon radicals where D = R4WSi02/2 where R4 and R5 are each independently selected monovalent one to forty carbon atom hydrocarbon radicals, with the stoichiometric subscript, x, ranging from about 1 to about 10,000 wherein the viscosity of the polyorganosiloxane ranges from about 1 to about 10,000,000 centipoise at 25 OC, 60SI-1843 5 (ii) from about 0.01 to about 50.0 percent by weight of a finely divided silica having a size ranging from about 0.001 to about 1,000 microns average particle diameter; (iii) from about 0.10 to about 50.0 percent by weight of an emulsifier or mixture of emulsifiers having on average a hydrophilic lipophilic balance ratio ranging from about 2 to about 20; (iv) from about 0.001 to about 20.0 percent by weight of a thickening agent or mixture of a water soluble thickening agent selected from the group consisting of polyacrylates, polyarnides, p olvarnines, stvrene sulfonate polymers, polyethylene oxides and cellulose derivatives having a molecular weight ranging from about 100 to about 100,000,00 dalton; and (v) from slightly greater than 0 to about 20.0 percent by weight of water, wherein when said water-:in-oil emulsion is added to a quantity of water greater in weight than the weight of said water-in-oil emulsion said emulsion inverts to an oil-in-water emulsion wherein said oil-in-water emulsion reduces foaming; (b) adding the water-in-oil emulsion to a quantity of water having a weight greater than the quantity of the water-in-oil emulsion; and (c) inverting the emulsion from a water-in-oil emulsion to an oil-in water emulsion whereby the rate of foam collapse exceeds the rate of foam formation.

Detailed Description of the Invention

The present invention is a water-in-oil emulsion comprising:

(a) from about 1 to about 99 percent by weight, preferably from about to about 95 percent by weight, more preferably from about 25 to about 90 percent by weight, and most preferably from about 60 to about 85 percent by weight of a polyorganosiloxane of the general formula 60SI-1843 6 MD.M where M = R1R2R3SCi/2where R', R2. and R3 are each independently monovalent one to forty carbon atom hydrocarbon radicals, preferably one to twenty carbon atom hydrocarbon radicals, more preferably one to ten carbon S atom radicals, and most preferably methyl, ethyl, n-propyl, i-propyl, tri fluoro-propyl, n-butyl, i-butvl, sec-butyl, n-pentvl, i-pentvl, neo- pentyl, n hexyl, Aexyl, phenyl, and benzyl; where D = R4R5Si02/2 where R4 and R5 are each independently monovalent one to forty carbon atom hydrocarbon radicals, preferably one to twenty carbon atom hydrocarbon radicals, more preferably one to ten carbon atom radicals, and most preferably methyl, ethyl, n-propyl, i-propyl, tri fluoro-propyl, n-butyl, i-buty], sec-butyl, n-pentyl, i-pentyl, neo- pentyl, n hexyl, i-hexyl, phenvI, and benzA with the stoichiometric subscript x, ranging from about 1 to about 10,000, preferably from about 10 to about is 5,000, more preferably from about 50 to about 3,000, and most preferably from about 100 to about 1,000, wherein the viscosity of the polyorganosiloxane ranges from about 1 to about 10,000,000 centipoise at 250C, preferably from about 10 to about 1,000,000 centipoise at 25 cC, more preferably from about 50 to about 100,000 centipoise at 25 OC, and most preferably from about 100 to about 10,000 centipoise at 25 OC; (b) from about 0.01 to about 50.0 percent by weight, preferably from about 0.10 to about 30.0 percent by weight, more preferably from about 0. 50 to about 20.0 percent by weight, and most preferably from about 1.0 to about 10.0 percent by weight of a finely divided silica having a size ranging from about 0.001 to about 1,000 microns average particle diameter, preferably from about 0.010 to about 100 microns average particle diameter, more preferably from about 0.050 to about 50 microns average particle diameter, and most preferably from about 0.100 to about 10 microns average particle diameter; 60SI-1843 7 (c) from about 0.10 to about 50.0 percent by weight, preferably from about 1.0 to about 40.0 percent by weight, more preferably from about 5.0 to about 30.0 percent by weight, and most preferably from about 10.0 to about 20.0 percent by weight of an emulsifier or mixture of emulsifiers having on average a hydrophilic lipohilic balance (HLB) ratio ranging from about 2 to about 20, preferablv from about 3 to about 18, more preferably from about 4 to about 16, and most preferably from about 5 to about 14; and (d) from about 0.001 to about 20.0 percent by weight, preferably from about 0.010 to about 15.0 percent by weight, more preferably from about 0.050 to about 10.0 percent by weight, and most preferably from about 0. 10 to about 5.0 percent by weight of a thickening agent or mixture of thickening agents that are water soluble polymers selected from the group consisting of polyacrylates, polyamides, polyarnines, styrene sulfonate polymers, polyethylene oxides and cellulose derivatives having a molecular weight ranging from about 100 to about 100,000,00 dalton; preferably from about 1,000 to about 50,000,000 dalton; more preferably from about 10,000 to about 10,000,000 dalton; and most preferably from about 100,000 to about 5,000, 000 dalton; and (e) from slightly greater than 0 to about 20.0 percent by weight, preferably from about 0.01 to about 15.0 percent by weight, more preferably from about 0.050 to about 10.0 percent Eoy weight, and most preferably from about 0.100 to about 5.0 percent by weight of water, which composition is an antifoam composition.

The choice of emulsifier is governed by two considerations: 1) miscibility in the silicone, and 2) the HLB ratio. It is necessary that the emulsifiers be miscible with the silicone phase in order to provide a water-in oil emulsion that inverts upon dilution to an oil-in-water emulsion.

Miscibility in the silicone is determined by a simple test wherein the silicone and the emulsifier are mixed and heated to between 30 and 50 -C. The 60SI-1843 8 mixture is held in this temperature range until a homogeneous mixture is obtained. Then the mixture of emulsifier and silicone is cooled to room temperature. Applicants define a silicone miscible emulsifier as that emulsifier which forms a homogeneous mixture with the silicone after heating to between 30 and 50 -C followed by cooling to room temperature.

Clearly, an emulsifier that does not form a homogeneous mixture is not miscible. While some emulsifiers will satisfy the criterion of this test independent of the silicone used, other emulsifiers may be more or less satisfactory depending on the viscosity of the silicone. The second condition imposed on the emulsifying agent is that the water-in-oil emulsion initially formed must invert to an oil-in-water emulsion upon dilution with water.

Thus miscibility and the ability to invert the emulsion upon dilution provide the necessary and sufficient conditions to define the emulsifier.

A preferred class of emulsifying agents are the ester derivatives of oleic acid. Thus for example oleic acid mo_no-, di, and tri-glycerides, polyethylene oxide sorbitan mono-, di- and tri-oleates and the like are preferred emulsifying agents i.e. oleate surfactants.

Within the range of HLB values that are most preferred for the emulsifier, the oleate derivatives having the general formula:

QO 0 QO-- -CH(OH)-CH2-0-% 11 -(CH2)7-CH=CH-(CH2)7-CH3 0 where each Q is independently defined by the formula -(CRIIR12CR13RI4-()-).-H where R", RI2, R13, and 1114 are either hydrogen or one to ten carbon atom monovalent hydrocarbon radicals and n ranges from 0 to about 100, have been found to be particularly effective.

The most preferred range of the HLB ratio is from 5 to 14. As this range is increased at its extremes, a larger number of miscible surfactants 60SI-1843 9 may be employed to prepare a water-in-oil emulsion that inverts to an oil- in water emulsion upon dilution. However, as the range is widened to values lower than 5 or greater than 14, the stability of the water-in-oil emulsion prior to dilution with water tends to deteriorate.

The thickening agents are generally water soluble polymers that may be anionic, non-ionic, or cationic in either solid or liquid form. Generally any appropriate thickening agent may be used as long as the emulsion is not broken by the thickening agent. The thickening agents may be any suitable water soluble polymer that does not break the emulsion. Particularly preferred thickening agents are thickening agents that are water soluble polymers selected from the group consisting of polyacrylates, polyamides, polyamines, styrene sulfonate polymers, polyethylene oxides and cellulose derivatives having a molecular weight ranging from about 100 to about 100,000,00 dalton.

The water-in-oil emulsions antifoam agents of the present invention are generally prepared by mixing a silicone, a water-soluble polymer, emulsifiers, water and an optional neutralizing agent. The following examples are provided to illustrate the invention and are not intended in any to limit the scope of the appended claims. All U.S. patents referenced herein are herewith and hereby incorporated by reference. ExjRerimental Examl2les 1 - 3 Table 1 shows the weights of the various components used to prepare an antifoarn composition that can be diluted with water.

60SI-1843 10 Table 1: Antifoam Compositions Coml2onent Example 1 Example 2 Example 3 weight in grams AF900OTM (1) 15 15 15 Arlacel 186 TkX2) 5 4 6 Polysorbate 80TM(3) 5.14 6 4 SF96-35OTM(4) 15 15 15 EMA1 OTWS) 0.47 0.47 0.47 Notes to Table 1:

1. AF900OTM is an antifoam composition containing hexamethyldisilazane treated silica and polydimethylsiloxane, manufactured by GE Silicones, Waterford, New York.

2. Arlacel 186 TM is a mixture of fat forming fatty acid mono- and diglycerides manufactured by ICI Americas of Wilmington, Delaware.

3. Polysorbate 8OTM is a polyethylene oxide (20) sorbitan mono-oleate manufactured by ICI Americas of Wilmington, Delaware.

4. SF96-35OTM is a polydimethylsiloxane having a viscosity of 350 centipoise at 10 25 -C manufactured by GE Silicones of Waterford, New York.

5. EMA1OTM is a polymer emulsion containing copolymer of acrylamide and sodium acrylate manufactured by Chemtall of Riceborough, Georgia.

Example 4

A concentrated antifoam composition was prepared as follows: 30 g of Span 80Tm (sorbitan mono-oleate from ICI Americas), 70 g Tween 85TM (polyethylene oxide (20) sorbitan tri-oleate from ICI Americas), 180 g SF96- 350 and 20 g of a hexamethyldisilazane treated precipitated silica were mixed and homogenized until uniform. 38 g of the mixture thus prepared was blended with 2 g EM533 Tm. a water-in-oil emulsion of about 40 weight 60SI-1843 percent acrylamide and sodium acrylate copolymer. The resulting antifoarn concentrate was an emulsion that could be easily diluted with water.

Example 5

A pre-mix consisting of 40.2 g of a mixture of 5 - 15 weight percent hexamethyldisilazane treated fumed silica and 85 - 95 weight percent hexamethyidisilazane treated precipitated silica with 361.8 g of a polydimethylsiloxane having a viscosity of 350 centipoise at 2,5 oC was homogenized until uniform. 68.0 g of Span 80'm and 12.7 g of Tween 85Tm were added to the silicone oil-silica mixture and mixed well. This premix was used to prepare additional antifoarn concentrates, and is designated in the later examples as pre-mix A.

Examples 6 - 9 Table 2: Antifoam Com]2ositions Component Exam21e 6 Exam121e 7 Examjple 8 ExamRle 9 weight in grams Pre-Mix A 15 is 15 is (Example 5)

SF 18-350 (1) 16.66 16.66 16.66 16.66 Span 80TM 3.12 2.64 2.04 1.53 Tween 8STm 0.61 1.21 1.81 2.62 EM5M1m(2) 0.2 0.2 0.2 0.2 Notes to Table 2:

(1) SF 18-350 is a polydimethylsiloxane having a viscosity of 350 centipoise at 25 OC manufactured by CE Silicones of Waterford, New York.

60SI-1843 12 (2) EMS33 TM is a water-in-oil emulsion of about 40 weight percent acrylamide and sodium acrylate copolymer manufactured by Cherntall of Riceborough, Georgia.

Example 10 g of the pre-mix A (example 5) was mixed with 26.41 g of Span 801m and 23.73 g Tween 85TM followed by the addition of 249.87 g of SF 18350 to make pre-mix B. Example 11

To 300 g of pre-mix B was added 6.1 g of Pemulen TR-lTm, 2.30 g of 50 weight percent aqueous NaOH and 5 g water. Pemulen TR_1 TM is a polyacrylic acid manufactured by B. F. Goodrich of Cleveland, Ohio. The preparation was dilutable with water.

ExamRle 12 To 10 g of Pernulen TR-lTM was added 96 g of water to prepare an aqueous slurry having 9.43 weight percent Pemulen TR-lTM. To22gof the aqueous slurry of Pemulen TR-lTM was added 200 g of pre-mix B followed by the addition of 0.65 g of 50 weight percent aqueous NaOH. The preparation is was dilutable with water.

Exam21e 13 A large reaction kettle was charged with 532.6 pounds of SF 18-350, 62 pounds of a mixture of 5 - 15 weight percent hexamethyldisilazane treated fumed silica and 85 - 95 weight percent hexamethyldisilazane treated precipitated silica and 0.6 pounds of oleic acid. The mixture was heated to 120 oC while mixing. After stirring for four hours at 120 OC the mixture was cooled to 25 C. 24.8 pounds of Pemulen TR_ITM was subsequently added and the mixture mixed until uniform. The resulting mixture was homogenized through a Gaulin mixer into a second kettle. To the second kettle containing the homogenized mixture was added 202.8 pounds of Span 8OTM, 107.8 60SI-1843 13 pounds Tween 85 Tm, and 953.2 pounds SF 18-350 followed by mixing for two hours. While the mixture was being mixed, 62 pounds of water at a temperature of 20 - 35 C was added. After the first hour of mixing 8 pounds of Proxel GXL Tm, 2 pounds of methylparaben, and 2 pounds of propyl paraben were added as a biocide package. When all of the materials had been mixed in 42.2 pounds of 10 weight percent aqueous NaOH were added.

This preparation was diluted with varying amounts of water as shown in Table 3.

Table 3: Dilution of Antifoam Concentrate from ExamRle 13 Designation Parts Water, Parts Total Parts, Silicone level, by weight Example 13 by weight weight Preparation, percent by weight 13A 1 is 16 5 13B 1 7 8 10 13C 1 3 4 20 13D 1 1.66 2.66 30 The viscosity of the various diluted preparations of example 13 was adjusted by the addition of 10 weight percent aqueous acetic acid. Sufficient acetic acid solution was added to change the pH which resulted in changing the viscosity of the diluted concentrate. As shown in Table 4, relatively small changes in pH level produce significant changes in the viscosity of the antifoarn concentrates.

60SI-1843 14 Table 4 Viscosi!y vH Relations for Antifoam Concentrate 13B 13C 13D pH viscosi!Y pH Viscosi pH viscosi!Y, cps at 250C cps at 25cC cps at 25oC 5.80 8,870 5.40 18,700 6.15 22,600 5.22 4,070 5.00 9,400 5.25 14,800 5.15 815 4.59 2,400 4.48 11,400 4.97 230 4.40 675 4.30 3,700 4.10 1,900 4.03 1,150 60SI-1843 is

Claims

1. A water-in-oil emulsion comprising:

(a) from about 1 to about 99 percent by weight of a polyorganosiloxane of the general formula : MD.M where M = R1R2R3Si0112where R', R2. and R3 are each independently selected monovalent one to forty carbon atom hydrocarbon radicals where D = R4R5SiO2/

2 where R4 and R' are each independently selected monovalent one to forty carbon atom hydrocarbon radicals, with the stoichiometric subscript, x, ranging from about 1 to about 10,000 wherein the viscosity of the polyorganosiloxane ranges from about 1 to about 10,000, 000 centipoise at 2.5 oC; (b) frorn about 0.01 to about 50.0 percent by weight of a finely divided silica having a size ranging from about 0.001 to about 1,000 microns average particle diameter; (c) from about 0.10 to about 50.0 percent by weight of an emulsifier or mixture of emulsifiers having on average a hydrophilic lipophilic balance ratio ranging from about 2 to about 20; and (d) from about 0.001 to about 20.0 percent by weight of a thickening agent or mixture of a water soluble thickening agent selected from the group consisting of polyacrylates, polyamides, polyamines, styrene sulfonate polymers, polyethylene oxides and cellulose derivatives having a molecular weight ranging from about 100 to about 100,000,00 dalton; and (e) from slightly greater than 0 to about 20.0 percent by weight of water; wherein when said water-in-oil emulsion is added to a quantity of water greater in weight than the weight of said water-in-oil emulsion said emulsion inverts to an oil-in-water emulsion wherein said oil-in- water emulsion reduces foaming.

60SI-1843 16 2. The water-in-oil emulsion of claim 1 wherein the emulsifier has a hydrophilic lipophilic balance ratio ranging from about 3 to about 18.

3. The water-in-oil emulsion of claim 2 wherein the emulsifier has a hydrophilic lipophilic balance ratio ranging from about 4 to about 16.

4. The water-in-oil emulsion of claim 3 wherein the emulsifier has a hydrophilic lipophilic balance ratio ranging from about 5 to about 14.

5. The water-in-oil emulsion of claim 4 wherein the emulsifier is an ester of oleic acid.

6. The water-in-oil emulsion of claim 5 wherein the ester of oleic acid has the formula:

QO 0 QO--- H(OH)-CH2-0- 11 -(CH2)7-CH=CH-(CH2)7-CH3 0 where each Q is independently defined by the formula -(CR11RI2CRI3R14-0_).-H where RU, R12, R13. and R14 are either hydrogen or one to ten carbon atom monovalent hydrocarbon radicals and n ranges from 0 to about 100.

7. The water-in-oil emulsion of claim 5 wherein the ester of oleic acid comprises an ester of glycerin.

8. The water-in-oil emulsion of claim 5 wherein the ester of oleic acid comprises a mono-ester of glycerin.

9. The water-in-oil emulsion of claim 5 wherein the ester of oleic acid comprises a tri-ester of glycerin.

10. A water-in-oil emulsion consisting essentially of:

(a) from about 1 to about 99 percent tv weight of a polyorganosiloxane of the general formula ND,,M where M = R1R2RISiOi12 where R', R2, and R3 are each independently selected monovalent one to forty carbon atom hydrocarbon radicals 60SI-1843 17 where D = RIR5SiO2/2 where R4 and RI are each independently selected monovalent one to forty carbon atom hydrocarbon radicals, with the stoichiometric subscript, x, ranging from about 1 to about 10,000 wherein the viscosity of the polyorganosiloxane ranges from about 1 to about 10,000, 000 centipoise at 25 OC; (b) from about 0.01 to about 50.0 percent by weight of a finely divided silica having a size ranging from about 0.001 to about 1,000 microns average particle diameter; (c) from about 0.10 to about 50.0 percent by weight of an emulsifier or mixture of emulsifiers having on average a hydrophilic lipophilic balance ratio ranging from about 2 to about 20; and (d) from about 0.001 to about 20.0 percent by weight of a thickening agent or mixture of a water soluble thickening agent selected from the grou consisting of polyacrylates, polyamides, polyamines, styrene sulfonate polymers, polyethylene oxides and cellulose derivatives having a molecular weight ranging from about 100 to about 100,000,00 dalton; and (e) from slightlv greater than 0 to about 20.0 percent by weight of water, wherein when said water-in-oil emulsion is added to a quantity of water greater in weight than the weight of said water-in-oil emulsion said emulsion inverts to an oil-in-water emulsion wherein said oil-in-water emulsion reduces foaming.

11. A method for reducing foam comprising:

(a) preparing a water-in-oil emulsion of - any preceding clailn; (b) adding the water-in-oil emulsion to a quantity of water having a weight greater than the quantity of the water-in-oil emulsion; and (c) inverting the emulsion from a water-in-oil emulsion to an oil-in water emulsion whereby the rate of foam collapse exceeds the rate of foam formation.