CA2026911C - Stable clear isotropic liquid detergent compositions containing sodium carbonate - Google Patents

Abstract

A clear, single phase, carbonate built liquid detergent composition, which is freeze/thaw stable, comprising (a) an anionic surfactant; (b) an oxyalkylate nonionic surfactant of the general formula:

Description

` ` 2026911 -ST~RT~ CLEAR ISOTROPIC LIOUID DETERGENT
CnMPosTTIoNs CONTAINING SODIUM CARBONAT~

BACKGROUND OF THE INVENTION

1. F;el~ Of the I~v~nt;on The present invention relates to a clear, single phase liquid detergent composition containing alkali metal carbonate builders, anionic and nonionic surfactants, a hydrotrope and optionally polycarboxylate builders which is freeze/thaw stable.
More specifically, the present invention relates to a dear, isotropic, liquid detergent composition containing alcohol ethoxylates1 anionic surfactants such as sodium alkyl benzene sulfonate, alkali metal carbonates as builders, a hydrotrope such as sodium cumene sulfonate and optionally polymers as adjuvant builders. The compositions are freeze/thaw stable, effective on oily soils and are significantly l!ess costly than comparable non-built formulations.
This invention further relates to a carbonate built liquid detergent composition based on high performing oxy-alkylate nonionic surfactants vhich are equivalent in performance to higher levels of commodity alcohol ethoxylates but which form stable, one-phase liquid compositions.
This invention also relates to a carbonate built liquid detergent composition which contains polyacrylate homopolymer and polymaleate copolymers which are added to enhance the building effects and reduce encrustation of fabrics from the insoluble carbonate salts.

2. Descr;pt;on of the Pr;or Art ~slop et al, U.S. Patent No. 4,619,446 disclose liquid detergent compositions suitable for laundry use which consist of water, electrolytes, builders and active ingredients. The liquid detergent composition of Haslop is actually a slurry composition which may be then formulated into a liquid or a powdered composition. The builders of Haslop include polyacrylates and maleic anhydride based copolymers. The composition formed according to Haslop is temperature stable and contains sodium carbonate, polyacrylates, maleic anhydride copolymers and other adjuvants. However, Haslop et al do not propose a clear, isotropic phase stable liquid built laundry detergent composition containing sodium carbonate as a builder, oxyalkylate nonionic surfactants, anionic surfactants such as sodium alkyl benzene sulfate, a hydrotrope such as sodium cumene sulfonate, and optionally, polyacrylate homopolymers or polymaleate c~polymers.

/

-PaYne et al, U.S. Patent No. 3,574,122 disclose a phase stable heavy duty liquid detergent emulsion composition comprising a synthetic organic nonionic detergent and trisodium nitrilo acetate in an aqueous 5 medium containing a ternary emulsion stabilizer system.
The ternary emulsion stabilizer system is a combination of a hydrolyzed linear copolymer of ethylene and maleic anhydride plus a hydrolyzed crosslinked copolymer of ethylene and maleic anhydride, a second stabilizer which 10 is a hydrotrope and a third stabilizer which is an electrolyte. There is no showing in Payne et al of forming a clear, isotropic, built, liquid laundry detergent composition which is freeze/thaw stable and contains the alkali metal carbonate builders of the 15 present invention.
BrierelY et al, U.S. Patent No. 4,530,775 disclose stable liquid detergent suspensions which stably suspend undissolved particulate matter. Alcohol ethoxylates are disclosed as surfactants of choice. There 20 is no showing of the clear isotropic built liquid detergent composition of the present invention.

Summary of the Invention It is an object of the present invention to provide a clear, single phase, carbonate built liquid detergent composition, which is freeze/thaw stable, comprising:
(a) an anionic surfactant (b) an oxyalkylate nonionic surfactant of the general formula:

lc~3 I H2CH3 RO~CH2-CH2-o ~ CH2CH -O ~ CH2-CH -O ~ H

i~

wherein R is an alkyl chain of from C8 to C15, x is a number from about 4 to 15, y is a number from about 0 to 15, z is a number from 0 to 5, and the molecular weight is from about 300 to 2,200;
(c) an alkali metal carbonate builder, (d) a single hydrotrope, and (e) the balance water.
A further object of the present invention is to provide a clear, single phase, carbonate built liquid 10 detergent composition, which is freeze/thaw stable, comprising:
(a) from about 1.0 to 15.0 percent by weight anionic surfactant (b) from about 0.1 to 7.0 percent by weight of an oxyalkylate nonionic surfactant of the general formula:
fH3 fB2CB3 RO(CH -C~2-O ~ CH2CH-O ~ CH2 z wherein R is an alkyl chain of from C~ to C~5, X iS a number from about 4 to 15, y is a number from about 0 to 15, z is a number from 0 to 5, and the molecular weight is from about 300 to 2,200;
(c) from about 0.1 to 5.0 percent by weight of an alkali metal carbonate builder, (d) from about 1 to 6 percent by weight of a single hydrotrope, and (e) the balance water.
Detergent "builders" are used primarily to improve the soil removal performance of the formulation.
They can act variously through chelation (or precipitation) of water hardness ions, improvement of particulate soil dispersion and -3a-~' V

202~911 by raising the pH of the wash liquor in order to saponify (and/or emulsify) oily soils. Many of these functions (chela-tion, saponification) cannot be achieved by simply increasing the amount of nonionic or anionic surfactants in a formula-tion. Even in cases where high levels of surfactants do provide the necessary benefit, a strong motivation for includ-ing builders in the formulation is that they provide equal performance at significantly lower cost.
Incorporating a builder into a liquid formulation lo is usually more difficult than for a powder detergent. In the United States, where heavy duty liquid detergents are usually clear, single phase compositions, the task is even more demanding. In addition to these formulation constraints other limitations of available builders result from government regulation (for example, non-phosphate legislation). Given these constraints and the need to formulate liquid detergent compositions which are cost effective, the use of sodium carbonate as a builder for clear, freeze/thaw stable, liquid systems is an important objective.
Liquid detergent formulations based on alkali metal carbonates have many benefits. Alkali metal carbonates act as a precipitating builder, preventing the interaction of calcium and magnesium ions with anionic surfactants which results in their loss in~efficiency. Additionally, alkali metal carbonate raises the pH of the wash water which can enhance the removal Cf oily or fatty soils through the mechanisms of saponification or emulsification. Because alkali metal carbonates, particularly sodium carbonate, are so inexpensive relative to nonionic surfactants, liquid formulations containing the carbonate are superior to unbuilt liquid detergents on a cost/performance basis. However, clear, single phase liquid detergents containing alkali metal carbonate, such as sodium carbonate, anionic and nonionic surfactants are difficult to prepare and are often found to be unstable when subjected to extremes of temperature like those found in conditions of storage and use. In particular, difficulties with nonionic surfactants are encountered owing to the tendency of the nonionic to "salt out" in the presence of high sodium ion content.
Surprisingly, it has been found that alkali metal carbonate built formulations containing oxyalkylate nonionic surfactants and LAS are freeze/thaw stable and provide excel-lo lent oily soil removal properties. The efficiency of theseformulations in oily soil removal has been found to be superior to non-built formulations containing higher levels of nonionic surfactant, so that the cost of the alkali metal carbonate based formulation is significantly lower. It has also been found that alkali metal carbonate built compositions contA;n;ng oxyalkylate nonionic surfactants outperform anionic liquid detergents built with higher levels of alkali metal carbonate. Thirdly, it has also been observed that alkali metal carbonate built liquids including oxyalkylate nonionic surfactants perform equal to formulations which contain higher levels of commodity ethoxylated alcohols. The compositions contA;n;ng higher levels of commodity ethoxylates are not only more expensive, but also are not stable through even one freeze/thaw cycle. Finally, the aforementioned carbonate built liquid detergents based on oxyalkylate nonionic surfactants can also contain small amounts of polyacrylate homopolymers or polymaleate copolymers which are added to enhance building and inhibit fabric encrustation by calcium carbonate. Liquid detergent compositions containing such polymers showed no signs of precipitation or phase separation when they were subjected to numerous freeze/thaw cycles.
Accordingly, it is an object of this invention to provide carbonate built liquid detergent compositions which are effective on oily soils and which are significantly less costly than comparable non-built formulations. It is a further object of this invention to provide alkali metal carbonate built liquid detergents based on high performing oxyalkylate nonionic surfactants which are equivalent in performance to higher levels of commodity ethoxylated alcohol surfactants but which torm stable, one phase liquid compositions. It is also an object of this invention to provide alkali metal carbonate built liquid detergents which contain polyacrylate homopolymer or polymaleate copolymers which enhance building effects and reduce encrustation of fabrics from insoluble carbonate salts.

D~T~TT~n D~CRIPTION OF T~ PEI~F~RR~n ~MRODIMENT

The present invention is directed to a clear, iso-tropic, built liquid detergent composition which is freeze/
thaw stable and contains an alkali metal carbonate as a builder. The composition is comprised of from 1.0 to 15.0 percent by weight of an anionic surfactant, from 0.1 to 7.0 percent by weight of the composition of an oxyalkylate nonionic surfactant, from 0.1 to 5.0 percent by weight of a builder such as sodium carbonate, from about 1.0 to 10.0 percent by weight hydrotrope, with the balance of the composition being water. The composition may also include polyacrylate homopolymers or polymaleate copolymers which are useful as additional builders and anti-encrustation agents.
The homopolymers contemplated for use in the present invention include polymers of a monoethylenically unsaturated monocarboxylic acid of 3 to 10 carbon atoms and its salt.
Additionally, the copolymers used in the invention contain cqpolymerized monomer units of monoethylenically unsaturated dicarboxylic acids and monoethylenically unsaturated ` 2026911 nonocarboxylic acids or olef ins. The copolymers are comprised of:
(a) from 90 to lo percent by weight of a mono-ethylenically unsaturated dicarboxylic acid of 4 to 6 carbon atoms, its salt and/or if appropriate, its anhydride, and a comonomer comprised of b) from 90 to 10 percent by weight of an alkene containing 4 to 22 carbon atoms, or c) from 9o to lo percent by weight of a monoethylenically unsaturated monocarboxylic acid of 3 to lo carbon atoms and/or its salt.
The starting monomers useful in the present invention are monoethylenically unsaturated monocarboxylic acids and/or their salts. They may contain from about 3 to 10 carbon atoms in the molecule. Acrylic acid and methacrylic acid are particularly suitable compounds, but it is also possible to use, for example, vinyl acetic acid, allyl acetic acid, as well as dimethyl acrylic acid.
The starting comonomers (a) are monoethylenically unsaturated dicarboxylic acids, their salts and/or, their anhydrides. Examples of suitable dicarboxylic acids of 4 to 6 carbon atoms are maleic acid, itaconic acid mesaconic acid, fumaric acid, methylene malonic acid and their salts and, in the appropriate cases, their anhydrides.
For the purposes of the present invention, salts of the carboxylic acids already mentioned are, preferably sodium salts and potassium salts, ammonium salts and organic amine salts,, such as those of the tri-C1-C4-alkyl amines, of hydroxyethylamine or of mono-, di- and tri-C1-C4 alkanolamines, and mixtures thereof.
The starting comonomers of (b) are selected from the group consisting of substituted and unsubstituted alkenes having from about 4 to 22 carbon atoms. Representative `
examples include 2-methylpropene, 1-pentene, 1-decene,diiso-butylene, 2,4,4-trimethyl-2-pentene and mixtures thereof.
The starting comonomers of (c) are monoethylencially unsaturated monocarboxylic acids and/or their salts. They may contain from 3 to lo carbon atoms in the molecule. Acrylic acid and methacrylic acid are particularly suitable compounds, but it is possible to use, for example, vinyl acetic acid, allyl acetic acid as well as dimethyl acrylic acid.
The general structure of a preferred homopolymer lo thus formed is as follows:
wherein X = H, Na or similar alkaline metals, and n is a number such that the total molecular weight of the polymer is from 1000 to 70,000. More preferably from 1000 to 8000.
The general structure of one preferred copolymer thus formed is as follows:

H IH

_ H COoX n wherein X, H, Na, or similar alkaline metals; A = an alkyl group having a chain length of 2 to 20 carbon atoms and preferably 6 to 10 carbon atoms, and m and n are numbers such that the monomer ratio is in the range of about 9:1 to 1:9 and a total average molecular weight of the copolymer is from 1,000 to 70,000. The most preferred monomer ratio for the copolymer is in the range of 1:1. The preferred molecular weight range of the copolymer is 1,000 to 25,000 and most preferably 12,000.
The general structure of a second preferred copolymer thus formed is as follows:

-H H H H
C C C- C--COOX COOX n H A m wherein X = H, Na, or similar alkaline metals; A = an alkyl group having a chain length of 2 to 20 carbon atoms and preferably 6 to 10 carbon atoms, and m and n are numbers such that the monomer ratio is in the range of about 9:1 to 1:9 and a total average molecular weight of the copolymer is from 1,oOO to 70,000. The most preferred monomer ratio for the copolymer is in the range of 1:1. The preferred molecular weight range of the copolymer is 1,000 to 25,000 and most preferably 12,000.
The general structure of a second preferred copolymer thus formed is as follows:

_ 7 ~ H
cbox coox H COOX

wherein X = H, Na or similar alkali metals and n and m are numbers such that the monomer ratio is in the range 9:1 to 1:9 and a total average molecular weight of the copolymer is from 1,000 to 70,000. The most preferred monomer ratio for the copolymer is in the range 1:1. The preferred molecular weight range of the copolymer is 1,000 to 10,000 and most preferably about 3,000.
The nonionic surfactants useful in the present invention comprise ethylene oxide and/or propylene oxide and/or butylene oxide condensation products with alcohols, alkyl phenols, fatty acid amides and mixtures thereof.
Preferably, the nonionic surfactant may be an oxyalkylate of _ the general structure:

fH3 CH2-CH3 RO(cH2-cH2-o ~ CH2-CH-O ~ CH2-CH-O ~ H

wherein R is an alkyl chain whose length is from about 8 to 15 carbon atoms, preferably 12 to 15 carbon atoms; x is a number from about 4 to 15, preferably 8 to 15; y is a number from about 0 to 15, preferably 1 to 4; and z is a number from about 0 to 5, and preferably 0.
The preferred range of the molecular weight of the oxyalkylate surfactant for use in the present invention is from about 300 to 2,200.
The carbonate builder is an alkali metal carbonate, and preferably, the alkali metal is sodium or potassium. Most preferably, the builder is a sodium or potassium carbonate, bicarbonate or sesquicarbonate, and mixtures thereof.
A wide variety of anionic surfactants may be utilized. Anionic surfactants can be broadly described as surface active compounds with negatively charged functional group(s). An important class within this category are the water-soluble salts, particularly alkali metal salts, of organic sulfur reactions products. In their molecular structure is an alkyl radical containing from about 8 to 22 carbon atoms and a radical selected from the group consisting of sulfonic or sulfuric acid ester radicals. Such surfactants are well known in the detergent art. They are described at length in "Surface Active Agents and Detergents", Vol. II, by Schwartz, Perry & Berch, Interscience Publishers Inc., 1958.
Particularly suitable anionic surfactants for the instant invention are the higher alkyl mononuclear aromatic sulfonates. They contain from 10 to 16 carbon atoms in the alkyl chain. Alkali metal or ammonium salts of these ` 2026911 sulfonates are suitable, although the sodium salts are preferred. Specific examples include: sodium linear tridecyl benzene sulfonate; and sodium p-n-dodecyl benzene sulfonate.
These anionic surfactants are present usually from about 1 to about 15% by weight of the total composition. More preferably, they are present from about 8% to about 10%.
The presence of a hydrotrope within the composition is highlydesirable. Hydrotropes are substances that increase the solubility in water of another material which is only partially soluble. Preferred hydrotropes are the alkali metal or ammonium salts of alkyl benzene sulfonic acid, toluene sulfonic acid and xylene sulfonic acid. Two highly preferred hydrotropes are the sodium salt of cumene sulfonic acid and phosphate esters. Hydrotropes are present from about 1% to about 10% by weight of the total composition, preferably at a level of 1 to 6% by weight.
Those skilled in the art recognize that the detergent compositions described herein may also contain incrustation inhibitors, perfumes, bleaches, corrosion inhibitors, antifoamers, optical brighteners, enzymes and other additives.
Those skilled in the art further understand that the present invention may optionally include any builde~ suitable for use in a liquid detergent composition. Examples of organic builder salts which can be used alone or in admixture with each other or with the preceding inorganic alkaline builder salts are alkali metal polycarboxylates, sodium and potassium citrate, sodium and potassium tartarate, sodium and potassium N-(2-hydroxyethyl)-ethylene diamine tetraacetates, sodium and potassium nitrilotriacetates, and sodium and potassium N-(2-hydroxyethyl)-nitrilo diacetates. These builders may be used in conjunction with alkali metal carbonates.
X

The following examples are presented to illustrate various aspects of the invention. Those skilled in the art understand they are not to be construed as limiting the scope or spirit of the invention.

EXAMPT.~S

St-~hil;ty Stu~;es:

The heavy duty liquid detergent formulations shown in Tables 1, 2 and 3 were tested for freeze/thaw stability (i.e. maint~;n;ng clarity without separation or precipitation.
This evaluation was carried out by alternatively subjecting the sample to -5F for 24 hours followed by warming to 70F
for 48 hours. The formulation was exposed to these temperature extremes for a total of six cycles. Results of the freeze/thaw study are also shown in Tables 1, 2 and 3.
In the first set of Examples, we investigated the effect of different hydrotropes on formula stability. As shown in Table 1, with formulas containing 5% Plurafac~ B-25-5, most hydrotropes ~or hydrotrope blends) were unable to insure stability through even one freeze/thaw cycle: The two exceptions (Examples 1 and 4) were sodium cumene sulfonate (Stepanate~ SCS) and a phosphate ester (Triton~ H-55). These hydrotropes were also effective with 7% Igepal~ C0-630 (Example 8) but not with 7% Neodol~ 25-7 (Example g) or 7%
Neodol~ 25-9 (Example 10).
The hydrotrope study shows the difficulty of formulating nonionic surfactants into carbonate built liquid detergents. Salting out of the nonionic is a major difficulty with these compositions and most hydrotropes are not effective in preventing it.

` 2026911 All of the formulations in table 1 showed some instability. The coposition containing 5% B-25-5, 5%
carbonate, and 10% Vista C-560 LAS was the most stable surviving four freeze/thaw cycles. Two approaches were taken to improve the stability of the formulation. Different types of LAS were investigated and lower levels of sodium carbonate or nonionic surfactant were used.
In Table 2 we show the results of a study of different LAS types and higher sodium carbonate levels. The data show that longer alkyl chains lead to instability, since the Biosoft~ D-62 formula (a Na salt of C12 LAS) does not survive one freeze/thaw cycle. Changing the counterion from sodium to protonated TEA significantly improves stability, since the formula with Biosoft~ N-300 (a C12 LAS) is stable through six freeze/thaw cycles and reconstitutes in only twenty-four hours. If the sodium carbonate level was increased to 7% however, formulas containing 5% B-25-5 and 10%
of either (Biosoft~ N-300 or VISTA~ C-560) were found to be unstable.
In Table 3 we show the compatibility of different polymers with carbonate built liquid detergents containing Plurafac~ B-25-5 (an oxyalkylate available from BASF
Corporation). By lowering the level of carbonate to 4% (5~
B-25-5) or the level of B-25-5 to 4% (5% carbonate) stable compositions can be formulated with Sokalan~ CP-9 copolymer (Examples 20 and 21) and Sokalan~ PA-30 polymer (Examples 24 and 25) (each polymer was included at 0.5% active).
Formulations containing higher levels of B-25-5 or carbonate were found to be unstable (Examples 26, 27 and 28).
Because sodium carbonate is a precipitating builder (forming calcium or magnesium carbonate in the presence of "_ water hardness ions) acrylate or maleate based polymers (Sokalan~ CP-9, CP-12 and PA-30 polymers) are included to inhibit encrustation of fabrics with insoluble salts. Thus the formulation of stable carbonate built liquid detergents containing encrustation inhibiting polymers of these types represents a significant advance over the present art.
The freeze/thaw stability experiments compiled in Tables 1-3 are evidence that carbonate built liquid detergents are difficult to formulate, particularly if they contain encrustation inhibiting polymers and an LAS with a C12 or higher alkyl chain. It is therefore surprising that stable carbonate built compositions can be formulated and that their oily soil detergency performance, as outlined in the next section, was equivalent to more expensive formulations containing higher levels of commodity ethoxylates.

TART~ 1 (T~'~FECT OF VARIOUS HYDROTROPES) F~XAMPT.~

CO~PON~NT 1 2 3 4 5 6 7 8 9 10 Plurafac~ B-25-5 5 5 5 5 5 5 Neodol~ 25-7 - - - - - - - - 7 Igepal~ C0-630 - - - - - - 7 7 - -Neodol~ 25-9 - - - - - - - - - 7 Vista C-560 10 10 lo lo 10 10 10 lo 10 lo Stepanate~ SCS 6 - - - - - - 6 6 6 Stepanate~ SXS - 6 5 5 5 5 6 Petro~ LBA
Triton~ H-55 Propylene Glycol Dowfax~ 3B2 .
Sodium Carbonate 5 5 5 5 5 5 5 5 5 5 Water 74 74 74 74 74 74 72 72 72 72 Freeze/thaw 4 NS NS l* NS NS NS 2 ,NS NS
Stability (#cycles) NS = Not stable: precipitation and/or phase separation after one freeze/thaw cycle.
0 * = Stable through one freeze/thaw; not evaluated further.

` 2026911 T~RT~ 1 CONT. (~FF~CT OF VARTOUS HYDROTROP~S) P~XI~MPT.h~

COMPON~NT 11 12 13 14 15 Plurafac~ B-25-5 5 5 5 5 5 10 Igepal~ C0-630 Vista C-560 10 10 10 10 10 Stepanate~ SXS - 5 5 5 5 Petro~ LBA
Petro~ LBA - - - 1 -Propylene Glycol 6 Dowfax~ 3B2 Sodium Carbonate 5 5 5 5 5 Water 74 74 74 74 74 Freeze/thaw CF CF NS NS NS
Stability (#cycles) CF = Cannot formulate: two phase system forms when components are mixed.

NS = Not stable: precipitation and/or separa-tion after one freeze/thaw cycle.

2026gII

TART.F. 2 10 T'.XAMPT.l;. No.
CO~PON~NT 16 17 18 19 Plurafac~ B-25-5 5 5 5 5 Igepal~ C0-630 Vista C-560 10 - - -Stepanate~ SCS 6 6 6 6 Biosoft~ D-62 - 10 Biosoft~ N-300 - - 10 10 Sodium Carbonate 7 5 5 7 Water 72 74 74 72 Freeze/thaw NS NS 6 NS
Stability (#cycles) NS = Not stable TART-~ 3 (CoMpATIBIT~TTy WITH POLYMERS) ~xa~pT-~ No COMPON~NT 20 21 22 23 24 25 26 27 28 Plurafac~ B-25-5 5 4 5 4 5 4 5 5 5 Igepal~ C0-630 - - - - - - 7 Vista C-560 10 10 10 10 10 10 10 10 10 Stepanate~ SCS 6 6 6 6 6 6 6 6 6 Sodium Carbonate 4 5 3 5 4 5 5 5 5 Sokalan~ CP-9 0.5 0.5 - - - - 0.5 Sokalan~ CP-12 - - 0.5 0.5 - - - 0.5 Sokalan~ PA-30 - - - - 0.5 0.5 - - 0.5 Water 74.5 74.5 75.5 74.5 74.5 74.5 73.5 73.5 73.5 Freeze/thaw 6 6 6 6 6 6 NS NS NS
Stability (#cycles) NS = Not stable .

MTx~n SOIT D~T~R~NCY:

The soil removal performance of liquid detergent composition containing sodium carbonate, LAS and different nonionic surfactants was assessed using a mixed soil load.
For the particulate soil, ground in clay swatches were used (Scientific Services) including three fabric types: cotton ( S-405); polyester (S-767) and D(65) /C(35) ( S-7435) . The oily soil consisted of Spangler sebum which was applied (Scientific Services) to the same three fabric types used with the clay soil. Two swatches of each fabric/stain combination were added to each Terg-o-Tometer pot along with one clean swatch of each fabric (a total of fifteen swatches per pot)*.
Wash conditions were 100F and 150 ppm water hardness (2:1 Ca++/Mg++ ratio). A hunter colorimeter was employed to monitor reflectance of the swatches before and after the wash. Changes in reflectance are reported for each fabric/soil combination along with the 95% confidence interval associated with each determination.
In Table 4A the sebum soil removal results are shown for carbonate built liquid detergents and one unbuilt formulation. As indicated in Table 4A, sebum soil removal results for the formula containing 5% B-25-5 are equal to results for compositions containing 7% of a commodity ethoxylate: Igepal~ C0-630, Neodol~ 25-7 or Neodol~ 25-9.

* After the method of Feighner J.A.O.C.S. 66 (1) 13 (1989).

2 02B91l -If this example of the invention (10% LAS, 5~
PLURAFAC~ B-25-5, 5% carbonate) is compared to an unbuilt formula with twice the level of commodity ethoxylate (10% LAS, 10% C0-630) or to an anionic formula with twice the level of carbonate and LAS (20% LAS. 10% carbonate), it is found to be superlor.
Clay soil removal data for the mixed soil detergency test is shown in Table 4B. At the 95% percent confidence level, all of the formulations tested performed equally well.
This result indicates that the formula containing 5%
PLURAFAC~ B-25-5 is equivalent in clay soil removal to formulas cont~;n;ng higher levels of commodity ethoxylates or to the anionic formula with higher LAS and carbonate.
The Terg-o-Tometer evaluations were reproduced in a washing machine study. In this work a Whirlpool Imperial washer was set on regular agitation for a timed ten minute cycle, followed by an untimed rinse using the regular machine settings. Seventeen gallons of warm (100F) Wyandotte tap water (ca. 100 ppm hardness) was used without adding additional water hardness ions. Five swatches of each fabric/stain combination were included. In addition to sebum and clay soiled cloth. EMPA-104/cottom (a carbon black/olive oil stain) was also evaluated.
Results are shown in Tables 5A (oily stains) and 5B
(particulate stains). This data shows that formulas containing 5% Plurafac~ B-25-5, give equal performance to compositions containing 7~ Igepal~ C0-630. Lower levels of Igepal~ C0-630 (5%) are less effective than 5% Plurafac~
B-25-5 in removing sebum soil from polyester fabric and are directionally inferior on blend (see table 5A). Thus this experiment confirms the Terg-o-Tometer studies reported above.

-These results show that the formula based on 5%
Plurafac~ B-25-5 provides equal detergency when compared to formulation cont~;n;ng higher levels-of commodity ethoxylates (7% Igepal~ C0-630, 7% Neodol~ 2507, 7% Neodol~ 25-9, and unbuilt 10% Igepal~ C0-630). Stability experiments detailed in Tables 1-3 also indicate that carbonate built (5%) formulas containing 5% PLURAFAC~ B-25-5 are freeze/thaw stable through four cycles, whereas those containing 7% Neodol~ 25-7 or 25-9 separate after one cycle. Formulas containing 7~ Igepal~
C0-630 are stable, but are more expensive owing to the higher level of nonionic. Taken together the detergency and stability data suggest that carbonate built liquid detergents containing Plurafac~ B-25-5 are more economical (because lower level of surfactants can be used with equal performance) and are more practical (because they do not separate under actual conditions of storage) than was previously believed possible.

Mixed Soil Detergency Performance of Liquid Detergents Sebum Soil Removal (Mixed Soil Load) at 100F

FO~MUT~TION COTTON poT~y~sT~R BT~ND TOTAT
10% LAS 11.7 (0.7) 14.3 (0.3) 13.2(0.7) 39.2 10% C0-630 10% LAS 12.1 ~3.1) 23.4 (0.3) 21.1 (1.4) 56.6 7% C0-630 5% Na2CO3 10% LAS14.3 (0.8) 22.6 (0.7) 21.1 (1.0) 58.0 7% 25-7 5% Na2CO3 10% LAS14.6 (1.7) 23.9 (0.6) 22.3 (1.0) 60.8 7% 25 9 5% Na2CO3 10% LAS14.0 (2.6) 24.0 (1.3) 22.3 (0.7) 60.3 5% B-25-5 5% Na2CO3 20% LAS 9.4 (3.6) 15.9 (0.7) 17.1 (0.6) 42.4 10% Na2CO3 Notes: 95% Confidence Intervals appear in paren-thesis. Shorthand designations used for nonionic surfactants are as follows:
C0-630 = Igepal~ C0-630; 25-7 = Neodol~
25-9 and B-25-5 = Plurafac~ B-25-5.

-TART~ 4B

Mixed Soil Detergency Performance of Liquid Detergents Clay Soil Removal (Mixed Soil Load) at 100F

FO~MUT.~TION COTTON poT.Y~ST~R BLEND TOTAL
10% LAS 17.9 (2.6) 25.3 (0.7) 27.7(0.6) 70.9 10% C0-630 10% LAS 16.8 (2.8) 24.7 (0.6) 27.1 (1.4) 68.6 7% C0-630 5% Na2CO3 10% LAS 15.9 (3.3) 25.0 (0.8) 27.5 (0-4) 68.4 7% 25-7 5% Na2CO3 10% LAS 17.5 (1.8) 25.6 (0.5) 27.1 (0.4) 70.2 7% 25 9 5% Na2CO3 10% LAS 17.2 (2.7) 25.7 (1.3) 27.7 (0.7) 70.6 5% B-25-5 5% Na2CO3 20% LAS 15.8 (1.5) 23.8 (1.0) 26.7 (0.6) 66.3 10% Na2CO3 Notes: 95% Confidence Intervals appear in paren-thesis. Shorthand designations used for nonionic surfactants are as follows:
C0-630 = Igepal~ C0-630; 25-7 = Neodol~

25-7 = Neodol~; 25-9 = Neodol~ 25-9 and B-25-5 = Plurafac~ B-25-5.

202~911 `
TART.~ 5A

Mixed Soil Detergency Performance of Liquid Detergents oily Soil Removal (Mixed Soil Load) at 100F

FOR~JT~TION COTTON por~y~ TER BLEND TOTAL EMPA-104 10% LAS 9.6 (1.7) 21.8 (1.1) 22.0 (1.1) 53.4 8.4 (0.7) 7% C0-630 5% Na2CO3 10% LAS10.7 (2.0) 19.4 (1.0) 21.8 (0.9) 51.9 9.2 (1.6) 5% C0-630 5% Na2CO3 10% LAS9.2 (0.7) 21.9 (0.7) 23.1 (1.4) 54.2 7.3 (0.8) 5% B-25-5 5% Na2CO3 Notes: 95% Confidence Intervals appear in paren-thesis. Shorthand designations used for nonionic surfactants are as follows:
C0-630 = Igepal~ C0-630; B-25-5 Plurafac~ B-25-5.

.
TART~ 5B

Mixed Soil Detergency Performance of Liquid Detergents Clay Soil Removal (Mixed Soil Load) at 100F

FO~MUT.~TION COTTON pOT.Y~.~T~R BT~ND TOTAL
10% LAS 12.9 (0.5) 20.1 (0.8) 23.2 (0.8) 56.2 7% C0-630 10 5% Na2CO3 10% LAS 13.2 (2.5) 20.7 (0.4) 23.4 (0.6) 57.3 5% C0-630 5% Na2CO3 10% LAS 11.7 (3.2) 20.3 (1.1) 23.0 (1.0) 55.0 5% B-25-5 5% Na2CO3 Notes: 95% Confidence Intervals appear in paren-thesis. Shorthand designations used for nonionic surfactants are as follows:
C0-630 = Igepal~ C0-630; 25-7 = Neodol~
25-7 = Neodol~; 25-9 = Neodol~ 25-9 and B-25-5 = Plurafac~ B-25-5.

Claims (19)

1. A clear, single phase, carbonate built liquid detergent composition, which is freeze/thaw stable, comprising:
(a) an anionic surfactant (b) an oxyalkylate nonionic surfactant of the general formula:

wherein R is an alkyl chain of from C8 to C15, x is a number from about 4 to 15, y is a number from about 0 to 15, z is a number from 0 to 5, and the molecular weight is from about 300 to 2,200;
(c) an alkali metal carbonate builder, (d) a single hydrotrope, and (e) the balance water.

2. The composition of claim 1, further including a copolymer of the general formula:

( I) wherein X = H, Na or similar alkali metal; A = an alkyl group having a chain length of 2 to 20 carbon atoms and preferably 6 to 10 carbon atoms, and m and n are numbers such that the monomer ratio is in the range of about 9:1 to 1:9 and a total average molecular weight of the copolymer is from 1,000 to 70,000; a copolymer of the general formula:

(II) wherein X = H, Na or similar alkali metal and m and n are numbers such that the monomer ratio is in the range of about 9:1 to 1:9 and a total average molecular weight of the copolymer is from 1,000 to 70,000; or a homopolymer of the general formula:

(III) wherein X = H, Na or similar alkali metal, and n is a number such that the total molecular weight of the polymer is from 1000 to 70,000; and mixtures thereof.

3. The composition of claim 1, wherein said carbonate builder is an alkali metal carbonate.

4. The composition of claim 3, wherein the alkali metal carbonate builder is selected from the group consisting of sodium carbonate, sodium bicarbonate, sodium sesquicarbonate, potassium carbonate, potassium bicarbonate, potassium sesquicarbonate, and mixtures thereof.

5. The composition of claim 1, wherein said anionic surfactant is selected from the group consisting of C8 to C11 alkylbenzene sulfonates, C12 to C16 alkylsulfates, C12 to C16 alkylsulfosuccinates, sulfates ethoxylated C12 to C16 alkanols, and mixtures thereof.

6. The composition of claim 1, wherein the hydrotrope is selected from the group alkali metal and ammonium salts of alkyl benzene sulfonic acid, toluene sulfonic acid and xylene sulfonic acid.

7. The composition of claim 1, wherein the hydrotrope is selected from the group consisting of sodium cumene sulfonates and potassium salts of phosphate esters.

8. The composition of claim 1, wherein the polymer I has a molecular weight of from about 1000 to 25,000.

9. The composition of claim 1, wherein the copolymer (II) has a molecular weight of from about 1000 to 10,000.

10. The composition of claim 1, wherein the homopolymer (III) has a molecular weight of from about 1000 to 8000.

11 A clear, single phase, carbonate built liquid detergent composition, which is freeze/thaw stable, comprising:
(a) from about 1.0 to 15.0 percent by weight anionic surfactant (b) from about 0.1 to 7.0 percent by weight of an oxyalkylate nonionic surfactant of the general formula:

wherein R is an alkyl chain of from C8 to C15, x is a number from about 4 to 15, y is a number from about 0 to 15, z is a number from 0 to 5, and the molecular weight is from about 300 to 2,200;

(c) from about 0.1 to 5.0 percent by weight of an alkali metal carbonate builder, (d) from about 1 to 6 percent by weight of a single hydrotrope, and (e) the balance water.

12. The composition of claim 11, further including a polymer of the general formula:

( I) wherein X = H, Na or similar alkali metal; A = an alkyl group having a chain length of 2 to 20 carbon atoms and preferably 6 to 10 carbon atoms, and m and n are numbers such that the monomer ratio is in the range of about 9:1 to 1:9 and a total average molecular weight of the copolymer is from 1,000 to 70,000; a copolymer of the general formula:

( II) wherein X = H, Na or similar alkali metal and m and n are numbers such that the monomer ratio is in the range of about 9:1 to 1:9 and a total average molecular weight of the copolymers is from 1,000 to 70,000; or a homopolymer of the general formula:

(III) wherein X = H, Na or similar alkaline metals, and n is a number such that the total molecular weight of the polymer is from 1000 to 70,000; and mixtures thereof.

13. The composition of claim 11, wherein the alkali metal carbonate builder is selected from the group consisting of sodium carbonate, sodium bicarbonate, sodium sesquicarbonate, potassium carbonate, potassium bicarbonate, potassium sesquicarbonate, and mixtures thereof.

14. The composition of claim 11, wherein said anionic surfactant is selected from the group consisting of C8 to C11 alkylbenzene sulfonates, C12 to C16 alkylsulfates, C12 to C16 alkylsulfosuccinates, sulfated ethoxylated C12 to C16 alkanols, and mixtures thereof.

15. The composition of claim 11, wherein the hydrotrope is selected from the group alkali metal and ammonium salts of alkyl benzene sulfonic acid, toluene sulfonic acid and xylene sulfonic acid.

16. The composition of claim 11, wherein the hydrotrope is selected from the group consisting of sodium cumene sulfonates and potassium salts of phosphate esters.

17. The composition of claim 11, wherein the copolymer I has a molecular weight of from about 1000 to 25,000.

18. The composition of claim 11, wherein the copolymer II has a molecular weight of from 1000 to 10,000.

19. The composition of claim 11, wherein the homopolymer III has a molecular weight of from about 1000 to 8000.