CA2201500A1

CA2201500A1 - Improved grease removal in drains

Info

Publication number: CA2201500A1
Application number: CA002201500A
Authority: CA
Inventors: Elizabeth A. Cable; Vickie L. Humphrey; Suzanne M. Thompson
Original assignee: Individual
Current assignee: Clorox Co
Priority date: 1994-11-01
Filing date: 1995-10-27
Publication date: 1996-05-09
Also published as: EP0789636A1; JPH10508335A; MX9504605A; EP0789636A4; WO1996013342A1; BR9509121A; KR970706918A; PL321133A1

Abstract

The invention provides a drain remover formulation for removing a grease clog from a drain, said drain retaining a certain volume of water, in which the drain opener formulation comprises at least about 2% of at least one surfactant and, optionally, one or more cosurfactants, the surfactant:
cosurfactant ratio being at least 1:2, with the remainder being water, and the amount of formulation to retained water being about 1:10 to 1:50.

Description

~1096/13342 .-- ~ 2~ ~ J ~0 PCT/US95/13880 Title: I~PROVED GREASE REMOVAL IN DRAINS

S Bach~,ound of the Invention 1. Field of the Invention The invention relates to a drain cleaner in which a critical ratio and amount of at least one nonionic surfactant and, optionally, one or more cosurfactants, results in vastly improved greace removal in drains.

2. Brief Statement of the Related Art There are many approaches to removal or dissolution of grease buildups in kitchen sink and lavatory drainpipes. As is well known, the grease buildups tnemselves plug, clog or slow the drains, thus preventing or hindering the routine removal of wacte water in sinlcs and lavatories. In one commonly attempted solution, caustic chemicals, such as crystallized Iye, are introduced into tne standing water. While fat hydrolysis is intended by such an effort, in fact, theactual result is that an exotherrnic reaction caused by the reaction of the Iye and water merely heats the standing water to boiling, usuallv, without much action on the grease clog.

Another approach is to use a biological drain opener, in which a combination of fat-divesting microorv~nicm.c which colonizes and digests the clog over time. The microorv~ni.cmc typically include a mixture of bacteria which uses hydrolase enzymes to digest the clog, such as proteases and lipases. An example of this type of cleaner is described in EP 0 569 140 (Sybron Chemical Co.).

However, heretofore, no one had employed a drain cleaner in which a critical ratio and amount of at least one nonionic surfactant and, optionally, acosurfactant resulted in vastlv improved grease removal in drains.

WO 96/13342 < i ~ ,` ,' 2 ''~ PCT/US95/13880 Summarv of the Invention and Objects The invention provides an improved drain cleaner comprising a fat-solubilizing amount of at least one nonionic s~ ct~nt and, optionally, one or more cosurfactants, providing thereby at least about 0.08g of active surfactant to a grease clog.

In other embodiments, various additives can be added, inc ~u(ling, but not limited to, solvents, enzymes, microorv~ni~m~l fragrances, preservatives and other adjuncts known to those skilled in the art.

It is therefore an object of this invention to improve grease clog removal from the drain pipes and traps of sinks and lavatories.

It is another object of this invention to use a critical amount of surfactants to effect enhanced grease clog removal performance.

It is a further object of this invention to improve grease clog removal of enzyme or microorganism-cont~inir~g drain buildup removal formulations.

Detailed DescriPtion of the Invention The invention is an improved drain cleaner comprising a fat-solubilizing amount of at least one nonionic surfactant and, optionally, one or more cosurfactants thereby providing at least about 0.08g of actives to a grease clog.

Additional adjuncts such as solvents, enzymes, microorg~ni~m~, fragrances, dyes, preservatives and the like can be included to provide desirable attributes of such adjuncts.

In the application, effective amounts are generallv those amounts listed as the ranves or levels of in_redients in the descriptions which follow hereto. Unless otherwise stated, amounts listed in percentage ("%'s") are in weight percent of the composition~ unless otherwise noted.

~yog6/13342 ; ~ 20 ~ 5 ~ ~cT~us95ll388u 1. Nonionic Surfactants The nonionic surfactant is generally chosen from the C,0.l5 linear alkyl ethoxylates, with an ethylene oxide content of about 5 to 9 moles of ethylene oxide per mole of alcohol ("EO").

Representative surfactants include the Alfonic surf~et nt.~, sold by Conoco, such as Alfonic 1412-60, a C, 7_14 ethoxylated alcohol with 7 moles of EO; Neodol suff~rt~nt.~, sold by Shell Chemical Company, such as Neodol 25-7, a C,2 l5 ethoxylated alcohol with 7 moles of EO, Neodol 45-7, a C14 ,5 ethoxylated alcohol with 7 moles of EO; Su;fonic surf~t~ntc; also sold by ~llnt~m"n Chemical Company, such as Surfonic L24-7, a C,2 ,4 ethoxylated alcohol with 7 moles of EO; and Tergitol surf~ct~m~, sold by Union Carbide, such as Tergitol 25-L-7, a C,2 ,5 ethoxylated alcohol with 7 moles of EO. These nonionic surfactants are all li~uids, with generally 100% active level and excellent surfactancy, having hydrophile-lipophile balances ("HLB") in the area of about 8-15. It is these particular surf~c.t~nt~ which are especially important to the performance of theinventive drain cleaner.

2. Cosurfactants At least one cosurfactant is also optionally present in the invention and is typically either: ( I ) a linear alcohol ethoxylate with a lower EO content than the previously mentioned surfactant; (2) a secondary alcohol ethoxylate; (3) a branched chain ethoxvlated alcohol. such as a tridecyl ether ethoxvlate; (4) an alkyl ether ethoxylate; (5) an ethoxylated trimethyl nonanol derivative; and (6) an anionic alkyl phosphate ester. Mixtures of the foregoing are also included in this invention.

The linear alcohol ethoxylate wlth a lower EO content with typically a lower EO content than the surfactant would include: Alfonic 1412-40, a C,2 ,4 ethoxvlated alcohol with 3 moles of EO; Neodol 25-3, a Cl. ,5 ethoxylated alcohol with 3 moles of EO, Neodol 91-2.5, a C9 11 ethoxylated alcohol with 2.5 moles ofEO; Surfonic L24-3, a C~ 4 ethoxvlated alcohol with 3 moles of EO: and WO 96/13342 ~ ; 2 ~ PCT/US95/13880 ~

Tergitol 25-L-3, a C,~ 15 ethoxylated alcohol with 3 moles of EO. In co~ to the surfactant, this cosurfactant will generally act more as a wetting agent and will be more oil soluble than water soluble.

The secondary ethoxylated alcohols include Tergitol 15-S-3, a C~ ~s secondary ethoxylated alcohol. with 3 moles of EO, from Union Carbide.

The branched surfactants, especially preferred of which are tridecyl ethers, include Trycol TDA-3, a tridecyl ether with 3 moles of EO, from Henkel KGaA (formerly, Emery), and Macol TD 3, a tridecyl ether with 3 moles of EO, from PPG Industries.

The alkyl ether ethoxylates include C8 1~ alcohol alkoxycarboxylates, such as the Sandopan esters, e.g., Sandopan DTC, from Sandoz Chemicals.

The phosphate esters include 2-ethylhexyl, octyl, and decyl phosphates, sold by a number of manufacturers (See, also, Kirk-Othmer, Encyclopedia of Chemical Technology, 3rd Ed., p. 361, (1983), incorporated herein by reference).

The amount of surfactant and cosurfactant to be included in the novel drain opener formulations herein should be present in the formulation at a level aboveabout 1.5%, but below about 6%, with the greatest effect achieved between 2.5%
to 5%. It has surprisingly been found that the level of surfactant and cosurfactant ("Total Surfactant level") is critical. First, while a low level of Total S~ r,t~nt (e.g., 1%) is ineffective to remove a fatty clog, it has also been found that once the critical threshold amount to dissolve/disperse the fatty clog has been achieved,there is a peak effect which is not further improved once the 6% level has been exceeded. Further, there is a relationship between the surfactant and the cosurfactant, when present, in which the ratio of surfactant to cosurfactant must be at least 1: '. and is most preferably greater than 1:1.

~096/13342 ~ s ~ ~ 22~ 1 5 ~o PCT/US9~113880 Because of the limited surface area of a clog which is available to be acted on by the s~ ct~nt, or sllrf~ct~nt/cos~ .t~nt mixture, it has been discovered that a critical amount of the s-~rf~ct~nt, or surf~ct~nt/cosurfactant mixture effectively removes/disperses grease. And, beyond this critical amount, little or no furthereffect is seen. It is spec~ ted that because there is such a limited surface area in the drain for the surfactant to attack, that this results in the need for the critical amount. This is thus drarnatically unlike hard surface cleaning, where there is a linear correlation between the amount of s~ ct~nt used and the amount of soil removed or lifted from the soiled substrate.

Moreover, there is a crucial relationship between the critical amount of surfactant and cosurfactant, and the surface area of the grease clog. The typical drain trap (also called a "P-trap" because of its curved configuration) forms grease deposits having an elliptical shape. The ellipse has a long radius, R of generally about .75-1.50 inches (1.905-3.81 cm), and a short radius, R', of about 0.25-.75 inches (.635-1.905 cm). This results in a surface area (A=RR'7~) of grease clog of about 4.595. l9cm~ - 2?.79cm'. Moreover, because this grease clog traps water, c~ll.cing backflow and the commonly observed st~nriin~ water, it has been empirically deterrnined that the typical amount of drain opener delivered to said clog is a dilution of about 1:10 to 1:50, most preferably about 1:25. Thus, the present invention demonstrates that despite a relatively low level of active reaching the clog, there is an unexpectedlv marked increase in grease dispersion/dissolution/digestion such that the clog is effectively removed aftertreatment with the cleaner and water flows smoothly through the draintrap once more.

3. Microor~anisms and Enzvmes In the practice of this invention, it is pl efell~d to add fat, or rather, ,, lipid-digesting microorSg~ni~m~ and enzymes which will be stable in the drain opener formulations of this invention. For example, as mentioned in EP 0 569 140 (incorporated by reference thereto), numerous microorg~ni~m~, such as Bacillus~ Pseudomonas, Enterobacter and the like are useful for digesting the WO 96/13342 `~ ' 2 ~ ~ 1 5 0 0 PCT/US9S/13880 --Iipids presem in the _rease clogs. Especially preferred is Bacillus because of its lipid degrading characteristics as well as the fact that it, a gram positive rod, is a spore-forrner and thus is protected from attack from the external environment.

When such microorgz.ni.~m~ are present, it is ~(litionz~lly preferred to include a preservative so as to prevent or inhibit growth of contz~minz~.nt~. Suitable preservatives include Kathon GC, a 5-chloro-2-methyl-4-isothiazolin-3-one, Kathon ICP, a 2-methyl-4-isothiazolin-3-one, and a blend thereof. and Kathon 886, a 5-chloro-2-methyl-4-isothiazolin-3-one, all available from Rohm and Haas Company; Bronopol, a 2-bromo-2-nitropropane 1,3-diol. from Boots Company Ltd.; Proxel CRL, a propyl-p-hydroxybPn7oate, from ICI PLC; Nipasol M, an o-phenyl-phenol~ Na~ salt. from Nipa Laboratories Ltd.; Dowicide A, a 1,2-benzoisothiazolin-3-one. from Dow Chemical Co.; and Irgasan DP 200, a 2,4,4'-trichloro-7-hydroxydiphenylether, from Ciba-Geigy A.G. See also. Lewis et al., U.S. 4,25'~,694 and U.S. 4,105,431, inco,l,ol~led herein by reference.
Additionally preferred preservatives include alkyl (especially methyl) anthranilate, paraben and alkyl paraben. Nutrients, such as lipids, carbohydrates, proteins, yeasts. etc., are also preferred.

Additionally, hydrolase enzymes, such as proteases, amylases, cellulases and lipases may be included. Proteases are one especially preferred class of enzymes. They are selected from acidic, neutral and alkaline proteases. The terms "acidic," "neutral," and "alkaline." refer to the pH at which the enz~vmes' activity are optimal. An example of a neutral protease includes trypsin, a naturallv occurring protease. Alkaline proteases are available from a wide variety of sources, and are typicallv produced from various microorS~z~ni.~m~ (e.g., Bacillis subtilisin). Tvpical examples of alkaline proteases include Maxatase~ and Maxacal~) from International BioSynthetics, Alcalase~. Savinase~ and Esperase~. all available from Novo Nordisk A/S. See also Stanislowski et al., U.S. 4~511,490. incorporated herein by reference.

220 t 50~
~0 96113342 l ~ 7 PCT/US95/13880 Further suitable enzymes are amylases, which are carbohydrate-hydrolyzing enzymes. It is also pl~re~ d to include mixtures of amylases and proteases. Suitable arnylases include Rapidase(~, from Société
Rapidase, Termamyl~ from Novo Nordisk A/S, T~k~th~rm~ from Solvay Enzymes, and Maxamyl(E~) from International BioSynthetics.

Yet other potentially suitable enzymes are lipases~ such as those described in Silver, U.S. 3,950,277, Thom et al., U.S. 4,707,291, Wiersema et al., U.S.
5,Z96,161 and 5,030.240, all of which are in~ ol~ted herein by reference.

Still further suitable enzymes are cellulases, such as those described in Tai, U.S. 4.479,881, Murata et al.. U.S. 4,443,355, Barbesgaard et al., U.S. 4,435,307, and Ohva et al., U.S. 3,983.08'~. incorporated herein by reference.

The hydrolytic enzyme should be present in an a}nount of about 0.0001-1% (based on 100% active enzyme; most commercially vended enzymes are sold as liquids, slurries, prills or solids, in which either a liquid or solid filler/stabilizer is included, e.~., propylene glycol). Mixtures of any of the foregoing hydrolases are desirable, such as protease/amylase blends.

5. OrPanic Solvents The solvent can be selected from both water soluble and water miscible organic solvents and from poorly water soluble or~anic solvents. Some of the water soluble solvents include C, 6 alkanol. C3 24 alkylene glycol ether, and mixtures thereof. The alkanol can be selected from methanol, ethanol, n-propanol. isopropanol, butanol. pentanol. hexanol, their various positional isomers, and mixtures of the foregoing. In the invention, it has been found mostpreferable to use isopropanol. usually in conjunction with a ~Iycol ether. It may also be possible to utilize in addition ~o. or in place of, said alkanols. the diols such as methylene. ethylene. propylene and butylene glycols, and mixtures thereof. The poorly soluble solvents can include such materials as d-limonene, pine oil. and other terpene derivatives, such as terpene hvdrocarbons (e.g,s., ! 5 ! ~
WO96/13342 8 ~20 1 5G0 PCT/US95/13880 ~

tertiarv alcohols and ethers) and alicyclic hydrocarbons, such as methylcyclohexane .

The amount of solvent present may vary from 0 to 50%, more preferably 0 to 10%, but such level is not critical.

6. Builder A builder may be selected from organic and inorgauic builders, such as from the group consisting of: ethylene diarnine tetr~et~tes (EDTA), carboxylates. such as citric, glutaric or acetic acids (and their salts), all;ali metal carbonates, alkali metal silicates, alkali metal phosphates, and mixtures thereof.
Optionally, a co-builder selected from ammonium, alkali metal and alkaline earthmetal hydroxides. may be desirable. Certain builders also act as buffers, both acidic and basic~ and their inclusion may also be desirable herein. As well, buffers, such as NaOH, H,SO4, HCI, etc., may be desirable.

The level of builder can be fairly low, but is not critical. The amount herein can vary from about 0 to 15%, more preferably 0 to 5%. In preferred compositions of this invention, the builder is below 1%.

7. Water and Miscellaneous Since the drain opener is an aqueous cleaner with relatively low levels of actives, the principal ingredient is water, which should be present at a level of at least about 50%, more preferably at least about 80%, and most preferably, at least about 90%. Deionized water is most preferred.

Small amounts of adjuncts can be added for improving cleaning performance or aesthetic qualities of the cleaner. Adjuncts for cleanin_ include- additional surfactants. such as those described in Kirk-Othmer. Encvclopedia of Chemical Technolo~y~ 3rd Ed., Volume 22, pp. 332-432 (Marcel-Dekker. 1983), which are incorporated herein bv reference. Aesthetic adjuncts include fragrances, such as those available from Givaudan. IFF, Quest and others, and dyes and ~pO96/13342 , ; ~ PCT/US95/13880 pigrnents which can be solubilized or suspended in the formulation, such as di~minoanthra~uinones. The amounts of these cleaning and aesthetic adjuncts should be in the range of 0-2%, more preferably 0-1%.

In the following E~perimental section, the surprising performance benefits of the various aspects of the inventive cleaner are demonstrated.

WO 96/13342 ~ 2 3 1 ~ ~ ~ PCTIUS95/13880 EXPE~IENTAL

In the following experiments, it is demonstrated how the critical amount of surfactant present in the inventive drain openers provides surprisingly enhancedgrease clog removal. In order to demon~ te this phenomenon, tne conditions in a kitchen drain trap were sought to be sim~ l~te~ so that the effect could be rigorously tested through repeated iterations.

Example 1 As is known. the conditions in drain traps varies from household to household, and situation to situation. However, generally speaking, it has been observed that residents in households will pour melted fats and oils. such as butter~
bacon fat, cooking oils and the like, even though often cautioned a_ainst so doing.
When the molten fats and oils meet the residual water in the drain~ or, as is often the case, the water running from a spigot or faucet, these fats and oils solidify and begin to deposit on the closest horizontal surface, typically, the horizontal portion lS of a drain or P-trap. Because the drain trap is a pipe of circular bore, the forming grease plug or clog molds into an elliptical mass, which eventuallv clogs the trap.
Previous drain cleaners, such as caustic chemicals~ have been attempted with varying rates of success, since they will principally heat the standing water due to the e:cothermic heat of reaction from the combination of water and caustic.

To simulate the foregoing typical grease clog, individual 5 g portions of Crisco brand vegetable shortening were melted and poured into individual 250 ml beakers which were canted at a 45 angle. After the molten shortening hardened, this formed an elliptical grease plug. All of the examples used this sim--l~ted _rease plug which was found to be an excellent emulation of the grease clog found in drain traps.

Examples 2-1 1 In these examples, ten different formulations, all with 3% total surfactant, were prepared. In dosing the grease clo samples. the formulations were each ~vo96/13342 ~ a o PCT/US95/13880 diluted 1:25, since it has been found that there is always st~n~ling or residual water in drain traps, drain cleaners will be diluted prior to re~ in~ the clog from 1:10 to 1:~0, with 1:25 dilution being very repr~c~ ;ve.
The form~ tinns generally comprised a base fnrm~ tion (shown in TABLE I below) combinations of: s~ ct~nt A, which was a Cl"4 linear ethoxylated alcohol, with about 7 moles of ethylene oxide; cos~ ct~n~ B, which was a Cl, l4 linear ethoxylated alcohol, with about 3 moles of ethylene oxide; and coslltf~et~nt C, which was a tridecyl ether, with about 3 moles of ethylene oxide.

TABLE I
BASE FORMULATION
Ingredients Quantitv Actives Level Sllrf~rti7~nt A See ~Y~ c 100%
Cos~ t B See e Cos~ mt C See .,.~ s Bacillus spores 5xl07~l,u.~,s/
Nutrient .5%
EDTA .256% "
Dar~ blue dve .017%
Foam controller .005%
G~valiv~ 1' .004%
P~,s~valiv~ 22 .0026%
Green d,ve .0007 D.l. H.O3 q.s.
l Proxel 2Methvl ~nthr~nil~te 3 snffieient quantit,v of dPi~ni7~tl water to make up 3780 ml of fo, l""~ ;

TABLE II below shows the type and ratios of surfactants used.

~ ~ r WO96/13342 12 f 2 ~ 1 5 () O PCT/US95/l3880 TABLE II
Example 2 3 4 5 6 Surfactant A 16.67% 16.67%
Cosurfac~t 100% 50% 16.67%66.67%
B

Cosurfactant 100% 50% 66.67% 16.67%
C

Example 7 8 9 10 11 Surfactant A 33.33% 50% 66.67% 50% 100%
Cosurfactant 33.33% 16.67% S0%
B

Cosurfactant 33.33% 50% 16.67%
C

The formulations were dosed onto the sarnple grease plugs in a 1 :25 (vol./vol.) dilution, with deionized water. These samples were allowed to sit for about 24 hours at room temperature (~21C), rinsed, dried and then weighed to deterrnine grease removal. This procedure was repeated three times with each sample. The results after the third treatment are depicted in TABLE III below:

TABLE III

Example 2 3 4 5 6 % Grease0.4 1.7 1.8 2.6 6.2 Lost Example 7 8 9 10 11 % Grease15.8 21.3 24.9 25.2 26.9 Lost - -; 22~ ~ ~DO
~0 96/13342 - ~ 3 PCT/US95/13880 As can be seen from the foregoing TABLE m, those examples (7-11) wherein the ratio of surfactant to cos-lrf~ct~nt was at least 1:2 greatly outperformed the r~m~ining exarnples (2-6) where the arnount of ,c~ ct.nt to cos--rf~c.t~nt was less than 1:2.

Further, it was observed that when the total level of surfactant/cosurfactant is greater than 6%, the grease removal perforrnance was not enhanced and r~om,.ined fairly static. This, too, was quite surprising, since it is known in hard surface cleaning that to increase the level of cleaning active, i.e., surfactant, linearly increases the cleaning performance.

In the next set of Examples, the effect of the level of surfactants was tested. As mentioned above, it has been observed that the inventionls Total Surfactant Level is a critical level, in which excee~iing the critical level will either not improve the grease-removing performance of the invention, or, in fact, may actually harnper the performance. Further, the type of surfactant used is significant. In these Examples, the base formulation exemplified in TABLE I was again ~Itili7e~, with differing amounts of surfact~ntc added. In Example 12, 3%
total surfactant (a linear alkylbenzenesulfonate), was used. In Example 13, a ternary blend of surf~ct~nt.~ (total surfact~nt level: 3%) similar to Example 7 was used. In Example 14, a ternary blend of surf~ct~nt~ similar to Example 7 was used, except that the total surfactant level was 6%.

TABLE IV
Example Dav % GreaseLost 3 0.92%
7 32%
1 3 1 29%
2 48%
3 61%
7 63%

WO 96/13342 14 2 2 ~ ~ 5 0 p~US95/13880 ~

14 1 15%
2 17%
3 16%
7 32%

From TABLE IV, above, it can be seen that to use a different type of surfactant, in this case, an anionic surfactant in Example 12, will not achieve the same type of grease removal performance as achieved by the invention. Further, Example 14 is instructive in demon~ L~Ilg that when the outer limit of the invention is reached, namely, to exceed 6% surf~ct~nt then grease removal is notonly not enhanced, it may actually be impaired. This was a very surprising finding, given that for hard surface cleaners, one can typically see a linear relationship between the amount of surfactant added and the amount of soil removed. TABLE V below demonstrates the performance of the invention versus currently available commercial formulations.

In TABLE V, Example 15 is a currently available commercial liquid drain buildup remover, which uses about 3% norlionic surf~t~nt~ which are ethoxylated nonylphenol ethers. Example 16 is representative of the invention and uses a ternary surfactant blend, just as in Example 7, above. Example 17 is another commercially available liquid drain buildup remover which, however, uses only about 0.5% total nonionic surfactant, which is expected to comprise ethoxylated nonylphenol ethers. Example 17 also is believed to contain a small amount of lipase enzyme. Apart from the stated surfactant and/or enzymes, Examples 15 and 17 will contain somewhat roughly similar ingredients as set forth in the Base Formulation, TABLE I.

~VO 96/13342 ;, ~ , 2 2 PCT/US95113880 TABLE V
Example Day %Grease Lost 1 13%
2 43%
3 45%

7 46%
1 6 1 29%
2 4~%
3 61%
s 7 63%
17 1 14%
2 34%

5 36%

Thus, the Examples in TABLE V demonstrate further demonstrate that the type and amount of surfactant have a bearing on whether optimal grease removal performance can be achieved.

The above examples have been depicted solely for purposes of exemplification and are not intçnded to restrict the scope or embodiments of the invention. The invention is further illustrated with reference to the claimswhich follow hereto.

Claims

1. A method for removing a grease clog from a drain, said drain retaining a certain volume of water, the method comprising:
applying a drain opener formulation comprising at least about 2% of at least one surfactant and, optionally, one or more cosurfactants, said surfactant:
cosurfactant ratio being at least 1:2. with the remainder being water, with the amount of formulation to retained water being about 1:10 to 1:50.

2. The method of claim 1 wherein said clog is elliptical.

3. The method of claim 1 wherein said surfactant is a C10-15 alcohol ethoxylate, with 3-10 moles of ethylene oxide per mole of alcohol.

4. The method of claim 1 wherein said cosurfactant is selected from the group consisting of: (1) a linear alcohol ethoxylate with a lower EO content than the previously mentioned surfactant; (2) a secondary alcohol ethoxylate;
(3) a tridecyl ether ethoxylate; (4) an alkyl ether ethoxylate; (5) an ethoxylated trimethyl nonanol derivative; (6) an anionic alkyl phosphate ester; and mixtures thereof.

5. The method of claim 4 wherein said cosurfactant comprises (1) a linear alcohol ethoxylate with a lower EO content than the previously mentioned surfactant.

6. The method of claim 4 wherein said cosurfactant comprises (3) a tridecyl ether ethoxylate.

7. The method of claim 1 wherein said formulation further comprises at least one adjunct selected from the group consisting of: solvents, enzymes, microorganisms, dyes, fragrances, preservatives and mixtures thereof.

8. A drain opener for removing a grease clog from a drain. said drain retaining a certain volume of water, the drain opener formulation comprising at least about 2% of at least one surfactant and, optionally, one or more cosurfactants, said surfactant: cosurfactant ratio being at least 1:2, with the remainder being water, with the amount of formulation to retained water in said drain being about 1:10 to 1:50.