Liquid detergent compositions containing stabilizers to prevent phase separation

The invention pertains to aqueous liquid detergent compositions on the basis of nonionic and anionic or cationic detergents and electrolytes which include a effective amount of an anionic alkylpolyalkylene oxide derivative selected from the group consisting of: PA1 (1) anionic alkylpolyalkyleneoxide derivatives having the formula: EQU Y--(CH.sub.2).sub.p --[O--(CH.sub.2).sub.n ].sub.z --O--(CH.sub.2).sub.q --X, PA1 (2) anionic di(alkylpolyalkyleneoxide) derivatives having the formula: ##STR1## (3) anionic di(alkylpolyalkyleneoxide) derivatives having the formula: ##STR2## in which X is a salt of a mono-valent oxygen-containing anionic group, Y is hydrogen or a salt of a mono-valent oxygen-containing anionic group, Z is a phosphate or phosphonate salt, R is C.sub.1 -C.sub.3 alkynyl, q is 0-4, p is 0-4, z is 1-14, x is 0-14, y is 0-14 and x+y is 1-14 and n is 2-3. Inclusion of the alkylpolyalkyleneoxide derivatives results in an improvement of the long term storage stability of the detergent composition.

The present invention relates to aqueous liquid detergent compositions, and 
more in particular to such compositions comprising a nonionic detergent 
active material and/or an anionic derivative of a polyalkoxylated nonionic 
detergent active material, at least one anionic and/or cationic detergent 
active material, and electrolytes. 
This type of composition is well-known in the art, an important example 
thereof being aqueous built liquid detergent compositions which comprise 
one or more builder salts. It is generally known that special measures are 
required to provide such compositions with satisfactory stability thereby 
avoiding phase separation on long term storage. Such measures may include 
a critical balancing of the various ingredients, the use of special 
stabilizers, or the use of special processing steps. 
Analogous stability problems may occur with electrolytes other than builder 
salts, such as buffer salts, pH adjusting agents, fillers and the like. 
It has now been found that the instability problems in the above type of 
systems can be significantly reduced by inclusion therein of a special 
class of compounds which are mono- or dianionic derivatives of 
polyalkylene oxides to be specified hereunder in more detail. 
Accordingly, the present invention provides an aqueous liquid detergent 
composition which comprises: 
(a) a nonionic detergent-active material and/or an anionic derivative of a 
polyalkoxylated nonionic detergent-active material; 
(b) an anionic detergent-active material other than component (a) and/or a 
cationic detergent-active material; 
(c) one or more electrolytes; and 
(d) an effective amount of a stabilizing compound or mixture of stabilizing 
compounds selected from the group consisting of: 
(1) anionic alkylpolyalkyleneoxide derivatives having the formula: 
EQU Y--(CH.sub.2).sub.p --[O--(CH.sub.2).sub.n ].sub.z --O--(CH.sub.2).sub.q 
--X, 
(2) anionic di(alkylpolyalkyleneoxide) derivatives having the formula: 
##STR3## 
(3) anionic di(alkylpolyalkyleneoxide) derivatives having the formula: 
##STR4## 
in which X is a salt of a mono-valent oxygen-containing anionic group, Y 
is hydrogen or a salt of a mono-valent oxygen-containing anionic group, Z 
is a phosphate or phosphonate salt, R is C.sub.1 -C.sub.3 alkynyl, q is 
0-4, p is 0-4, z is 1-14, x is 0-14, y is 0-14 and x+y is 1-14 and n is 
2-3. 
The stabilizing compounds of the present invention belong to the class of 
salts of anionic alkylpolyalkylene oxide derivatives. 
In the preceding formulas, the polyalkylene oxide portions 
[O--(CH.sub.2).sub.n ].sub.x,y,z, of the stabilizing compound preferably 
consist solely of ethylene oxide units, but also mixtures of ethylene 
oxide and propylene oxide are suitable. The number of alkylene oxide units 
(x+y,z) may range from 1 to 14, and preferably lies within the range of 2 
to 12, the range of 4 to 10 being preferred most. 
The group X is a salt of a mono-valent oxygen-containing anionic group. 
Suitable are salts of oxides of carbon, sulphur and phosphorus, such as 
carboxylates, sulphates, sulphonates, sulphinates, thiosulphates, 
sulphamates, nitroamides, phosphates and phosphonates. 
In the case of mono(alkylpolyalkoxylated) stabilizing compounds group X may 
be attached directly to the alkylene oxide portion of the molecule, i.e. 
q=0, the end-standing group O.dbd.X then preferably being a sulphate salt. 
Between the alkylene oxide portion and the anionic group there may also be 
a short alkylene chain, in which case X preferably is a carboxylate salt. 
The alkylene chain may consist of up to four carbon atoms (q is 0-4) and 
preferably is methylene or ethylene. 
The group Y preferably is hydrogen, but may also be an salt of a second 
mono-valent oxygen-containing anionic group. In the latter case Y is 
selected from the same group as X, and may be equal to or different from 
X. 
Between Y or hydrogen (in the case of di(polyalkoxylated stabilizing 
compounds) and the alkylene oxide portion a short alkylene chain may be 
present consisting of up to four carbon atoms. The alkylene chain 
preferably is a straight saturated alkylene chain, in particular methylene 
or ethylene. 
R is a C.sub.1 -C.sub.3 alkynyl group, X then preferably being a 
carboxylate salt. Suitable examples of this class of stabilizing compounds 
are the mono- and di(alkylpolyalkoxylated) glyceric acid salts. 
Suitable counter cations for the anionic group(s) are hydrogen, ammonium 
and alkalimetal ions, preferably sodium, or equivalently charged amounts 
of alkaline earth metal ions. 
In the detergent compositions according to the present invention a single 
stabilizing agent or mixture thereof is included in an amount which will 
depend on the concentration and composition of the various detergent 
actives and the specific type of stabilizing compound which is used. 
Although the amount is often critical in that a concentration which is 
either too low or too high may result in non-satisfactory stabilizing 
behaviour, suitable concentrations can easily be determined by way of 
routine procedure. In general the concentration of the stabilizing 
compound or mixture thereof lies within the range of from 0.1 to 30%, in 
particular from 0.3 to 15%, such as from 0.5 to 5% by weight of the total 
composition. 
The invention is particularly applicable to liquid detergent compositions 
on the basis of binary or ternary active systems which comprise a nonionic 
detergent active or anionic derivative of a polyalkoxylated nonionic 
detergent-active in combination with one or more anionic and/or cationic 
detergent actives, and electrolytes. The anionic, cationic and nonionic 
detergent actives used in the present invention can be selected from any 
suitable conventional materials. The anionics comprise the well-known 
anionic detergents of the alkylaryl sulphonate type, the alkyl- and 
alkylether sulphate type, the alkane- and alkene sulphonate type etc. 
Numerous other examples can be found in Schwartz, Perry, Vol. II, 1958, 
"Detergents and Surface-Active Agents". 
Suitable nonionics detergent actives comprise ethylene oxide and/or 
propylene oxide condensation products with fatty alcohols, alkylphenols, 
fatty acids and fatty acid amides. Although also other types of nonionic 
detergent actives may be suitable, examples of which are given in the 
above mentioned reference, the alkylene oxide derived nonionic actives are 
preferred. 
As anionic derivatives of polyalkoxylated nonionic detergent active 
materials, those compounds are contemplated which are derived from 
alkoxylated nonionics by e.g. sulphation, phosphation or oxidation, such 
as the sulphated, phosphated or carboxylated polyalkylated nonionic 
detergent actives. 
Examples of cationic detergent-active materials are the quaternary ammonium 
compounds, such as di-(higher alkyl)di-(lower alkyl)ammonium halides. 
Although cationics can be used in combination with the nonionics, it is 
preferred to use anionic detergent-actives in combination with the 
nonionic detergent-actives. 
The ratio of anionic to nonionic detergent-active may vary from 10:1 to 
1:10. In the case where detergent compositions with suspending properties 
are desired this ratio preferably ranges from 5:1 to 1:1. The total amount 
of detergent-active material may vary from 2 to 50, preferably from 5 to 
35% by weight of the total composition. 
The electrolytes which are used in the present invention are those which 
cause salting-out of the detergent-active. In general the composition may 
contain from 1 to 60% by weight, preferably from 3 to 50% by weight and 
most preferably from 5 to 30% by weight of the salting-out electrolyte. 
Typical examples of salting-out electrolytes are water-soluble builder 
salts, such as the alkali metal ortho- and pyrophosphates, the alkali 
metal and ammonium tripolyphosphates, such as sodium tripolyphosphate, the 
alkali metal silicates, -borates, -carbonates, -sulphates and -citrates, 
alkali metal salts of nitrilotriacetate, alkali metal salts of 
carboxymethyloxysuccinate. Instead of the alkali metal salts also the 
ammonium salts can be used. Preferred electrolytes are sodium 
tripolyphosphate and/or sodium (di)-silicate. 
The composition of the invention may further contain all ingredients 
usually encountered in such products, such as enzymes, fluorescers, 
builders, such as zeolites, abrasives, such as calcite, anti-redeposition 
agents, germicides, opacifiers, suds boosters, foam depressants, corrosion 
inhibitors, perfumes, bleaching agents, bleach percursors, non-salting-out 
electrolytes, solvents, etc. 
The invention will now be further illustrated by way of example, in which 
all percentages are by weight of the total composition unless otherwise 
indicated.