Note: Descriptions are shown in the official language in which they were submitted.
WO93/09215 2 1 ~ 6 PCT/US92/09387
COLOR-STABILIZATION SYSTEM IN LIQUID DETERGENT COMPOSITIONS
Technical field
The present invention relates to liquid detergent
compositions. The compositions according to the present
invention are stabilized against color alteration.
Backqround of the invention
Liquid detergent compositions are well known in the art.
It is desirable that such compositions should have an
attractive color as the compositions aesthetics is a key
element in terms of consumer acceptance. A broad palette
of dyes is available to the detergent formulator in order
to address this need.
As an alternative, some compositions can be marketed
without dyes, when the color of the product without dyes is
sufficiently attractive.
However, it has been observed that in certain liquid
detergent formulations, the color of the fresh product
would not remain unchanged through prolonged periods. This
represents a problem for the detergent manufacturer as
detergents should be capable of withstanding prolonged
periods of storage without undergoing significant
alteration in any respect, including product aesthetics.
W093/0921S 2 1 2 2 9 8 6 PCT/US92/09387
The reasons for this color alteration have not been
precisely identified, but it is believed that such
ingredients as alkanolamines are to some extent responsible
for this phenomenon. Perfumes also appear to play a role,
quite undefined because of the complex nature of perfumes.
Thus, the extent of the color alteration phenomenon
throughout time varies from one composition to the other.
It has been observed that this color alteration phenomenon
occurs in detergent compositions, irrespective of the
presence of a dye, i.e. it is the color of the "base"
without the dye which is altered. Unfortunately, the
presence of a dye does not always suffice to mask the color
alteration phenomenon.
The above problem is more accute in "modern" liquid
detergents as these detergents tend to be formulated as so-
called concentrated liquid detergents wherein the
interaction between the different ingredients and therefore
the color alteration is favored. Also, these liquid
concentrated detergents often encompass the use of
alkanolamines which, as mentioned hereinabove, are to some
extent responsible for the color alteration phenomenon.
It is thus an object of the present invention to formulate
liquid detergent compositions which are stabilized against
color alteration throughout prolonged periods.
In response to this object, the present invention proposes
to formulate liquid detergent compositions which comprise
low levels of materials yielding various sulfite ions in
the detergent composition, as color-stabilizing compounds.
An advantage of the present invention is that it offers a
color stabilization system which is efficient in all
products where color alteration occurs, with or without
dye. It is another advantage of the present invention that
2 1 22~86
it proposes the use of simple chemicals, which are
commercially available and relatively inexpensive.
Summary of the Invention
The present invention relates to a liquid detergent
composition stabilized against significant color alternation
over prolonged periods of storage, which composition
comprises: A) from 5~ to 60~ by weight of an organic surface-
active agent; B) from 5~ to 35~ by weight of a builder system;
C) from 4~ to 16~ by weight of an alkanolamine component
selected from monoethanolamine, triethanolamine and mixtures
thereof; D) from 0.3~ to 0.6~ by weight of a perfume component
tending to cause color alteration; and E) 0.01~ to 0.1~ of a
color stabilizing compound or mixtures thereof selected from
the group of ammonium, alkanolammonium and metal salts of
sulfite, hydrogen sulfite and pyrosulfite.
Detailed Description of the Invention
The liquid detergent compositions according to the present
invention comprise conventional detergency ingredients and the
color stabilization system.
As the color stabilization system, the detergent compositions
according to the present invention comprise from 0.01~ to 0.1~
by weight of the total composition of a compound selected from
sulfite (So32~), hydrogenosulfite (HSO~-) or pyrosulfite salts
(S2Os2-). Suitable sulfite, hydrogenosulfite and pyrosulfite
salts include metal salts, ammonium salts and alkanolammonium
salts. Preferred salts for use herein are sodium, potassium,
calcium alkanolammonium and ammonium salts. These compounds
are commonly used as food preservatives and are therefore
commercially available. Hydrogenosulfite, sulfur dioxide and
sulfurous acid solutions are also commercially available.
l~i
2 1 22'~86
The preferred color-stabilizing compound according to the
present invention is sodium pyrosulfite.
Without wanting to be bound by theory, it is believed that it
is hydrogenosulfite ions which are mainly responsible for the
color-stabilizing effect observed. However, any of the
compounds described hereinabove can be added to the detergent
composition as said compounds are all believed to yield
hydrogenosulfite ions in the finished product. Alpha-
hydroxyalkyl sulfonic acids are therefore also suitable for
use in the compositions according to the invention as they
yield hydrogenosulfite ions in the finished product. Alpha-
hydroxyalkyl sulfonic acids can be prepared by reacting
aldehydes or ketones with Na bisulfite, as described for
instance in J. March, Advanced Organic Chemistry, McGraw-Hill,
1977, page 816. The alkyl chain length and configuration of
the alpha-hydroxy alkyl sulfonic acid is not critical herein.
Preferred alkyl chains are C1 to C1s aliphatic chains.
The rest of the liquid detergent composition according to the
present invention is made of conventional detergency
ingredients, i.e. water, surfactants, builders and others.
The liquid detergent compositions herein comprise from 5
to 60~ by weight of the total liquid detergent composition,
~. ,
WO93/09215 251 ~ 2 ~ 8 ~ PCT/US92/09387
preferably from 20% by weight to 40~ by weight of an
organic surface-active agent selected from nonionic,
anionic, cationic and zwitterionic surface-active agents
and mixtures thereof.
Suitable anionic surface-active salts are selected from the
group of sulfonates and sulfates. The like anionic
surfactants are well-known in the detergent art and have
found wide application in commercial detergents. Preferred
anionic water-soluble sulfonate or sulfate salts have in
their molecular structure an alkyl radical containing from
about 8 to about 22 carbon atoms. Examples of such
preferred anionic surfactant salts are the reaction
products obtained by sulfating Cg-C1g fatty alcohols
derived from e.g. tallow oil, palm oil, palm kernel oil and
coconut oil; alkylbenzene sulfonates wherein the alkyl
group contains from about 9 to about 15 carbon atoms;
sodium alkylglyceryl ether sulfonates; ether sulfates of
fatty alcohols derived from tallow and coconut oils;
coconut fatty acid monoglyceride sulfates and sulfonates;
and water-soluble salts of paraffin sulfonates having from
about 8 to about 22 carbon atoms in the alkyl chain.
Sulfonated olefin surfactants as more fully described in
e.g. U.S. Patent Specification 3,332,880 can also be used.
The neutralizing cation for the anionic synthetic
sulfonates and/or sulfates is represented by conventional
cations which are widely used in detergent technology such
as sodium, potassium or alkanolammonium.
A suitable anionic synthetic surfactant component herein is
represented by the water-soluble salts of an alkylbenzene
sulfonic acid, preferably sodium alkylbenzene sulfonates,
preferably sodium alkylbenzene sulfonates having from about
to 13 carbon atoms in the alkyl group. Another
preferred anionic surfactant component herein is sodium
alkyl sulfates having from about 10 to 15 carbon atoms in
the alkyl group.
W O 93/09215 2 1 2 2 ~ 8 6 P(~r/US92/09387
The nonionic surfactants suitable for use herein include
those produced by condensing ethylene oxide with a
hydrocarbon having a reactive hydrogen atom, e.g., a
hydroxyl, carboxyl, or amido group, in the presence of an
acidic or basic catalyst, and include compounds having the
general formula RA(CH2CH20)nH wherein R represents the
hydrophobic moiety, A represents the group carrying the
reactive hydrogen atom and n represents the average number
of ethylene oxide moieties. R typically contains from
about 8 to 22 carbon atoms They can also be formed by the
condensation of propylene oxide with a lower molecular
weight compound. n usually varies from about 2 to about
24.
A preferred class of nonionic ethoxylates is represented by
the condensation product of a fatty alcohol having from 12
to 15 carbon atoms and from about 4 to 10 moles of ethylene
oxide per mole or fatty alcohol. Suitable species of this
class of ethoxylates include : the condensation product of
C12-C15 oxo-alcohols and 3 to 9 moles of ethylene oxide per
mole of alcohol; the condensation product or narrow cut
C14-C15 oxo-alcohols and 3 to 9 moles of ethylene oxide per
mole of fatty(oxo)alcohol; the condensation product of a
narrow cut C12-C13 fatty(oxo)alcohol and 6,5 moles of
ethylene oxide per mole of fatty alcohol; and the
condensation products of a C10-Cl4 coconut fatty alcohol
with a degree of ethoxylation (moles EO/mole fatty alcohol)
in the range from 4 to 8. The fatty oxo alcohols while
mainly linear can have, depending upon the processing
conditions and raw material olefins, a certain degree of
branching, particularly short chain such as methyl
branching. A degree of branching in the range from 15% to
50% (weight%) is frequently found in commercial oxo
alcohols.
Suitable cationic surfactants include quaternary ammonium
compounds of the formula R1R2R3R4N+ where R1,R2 and R3 are
W O 93/09215 2 1 ~ 2 9 ~ 6 P~r/US92/09387
methyl groups, and R4 is a C12_15 alkyl group, or where R
is an ethyl or hydroxy ethyl group, R2 and R3 are methyl
groups and R4 is a C12_15 alkyl group.
Zwitterionic surfactants include derivatives of aliphatic
quaternary ammonium, phosphonium, and sulfonium compounds
in which the aliphatic moiety can be straight or branched
chain and wherein one of the aliphatic substituents
contains from about 8 to about 24 carbon atoms and another
substituent contains, at least, an anionic water-
solubilizing group. Particularly preferred zwitterionic
materials are the ethoxylated ammonium sulfonates and
sulfates disclosed in U.S. Patents 3,925,262, Laughlin et
al., issued December 9, 1975 and 3,929,678, Laughlin et
al., issued December 30, 1975.
Semi-polar nonionic surfactants include water-soluble amine
oxides containing one alkyl or hydroxy alkyl moiety of from
about 8 to about 28 carbon atoms and two moieties selected
from the group consisting of alkyl groups and hydroxy alkyl
groups, containing from 1 to about 3 carbon atoms which can
optionally be joined into ring structures.
Also suitable are Poly hydroxy fatty acid amide surfactants
of the formula R2-1C-N-Z, wherein R1 is H, C1_4hydrocarbyl,
O Rl
2-hydroxy ethyl, 2-hydroxy propyl or a mixture thereof, R2
is C5_31 hydrocarbyl, and Z is a polyhydroxyhydrocarbyl
having a linear hydrocarbyl chain with at least 3 hydroxyls
directly connected to the chain, or an alkoxylated
derivative thereof. Preferably, R1 is methyl, R2 is a
straight C11_15 alkyl or alkenyl chain or mixtures thereof,
and Z is derived from a reducing sugar such as glucose,
fructose, maltose, lactose, in a reductive amination
reaction.
W O 93/09215 2 1 2 2 9 8 ~ PC~r/US92/09387
The compositions according to the present invention may
further comprise a builder system. Any conventional
builder system is suitable for use herein including
polycarboxylates and fatty acids, materials such as
ethylenediamine tetraacetate, metal ion sequestrants such
as aminopolyphosphonates, particularly ethylenediamine
tetramethylene phosphonic acid and diethylene triamine
pentamethylenephosphonic acid. Though less preferred for
obvious environmental reasons, phosphate builders can also
be used herein.
Suitable polycarboxylates builders for use herein include
citric acid, preferably in the form of a water-soluble
salt, derivatives of succinic acid of the formula
R_CH(COOH)CH2(COOH) wherein R is C10_20 alkyl or alkenyl,
preferably C12_l6, or wherein R can be substituted with
hydroxyl, sulfo sulfoxyl or sulfone substitutents.
Specific examples include lauryl succinate, myristyl
succinate, palmityl succinate, 2-dodecenylsuccinate, 2-
tetradecenyl succinate. Succinate builders are preferably
used in the form of their water-soluble salts, including
sodium, potassium. ammonium and alkanolammonium salts.
Other suitable polycarboxylates are oxodisuccinates and
mixtures of tartrate monosuccinic and tartrate disuccinic
acid such as described in US 4,663,071
Suitable fatty acid builders for use herein are saturated
or unsaturated C10_18 fatty acids, as well as the
corresponding soaps. Preferred saturated species have from
12 to 16 carbon atoms in the alkyl chain. The preferred
unsaturated fatty acid is oleic acid.
A preferred builder system for use herein consists of a
mixture of citric acid, fatty acids and succinic acid
derivatives described herein above. The builder system
WO93/09215 2 1 2 2 ~ ~ ~ PCT/US92/09387
according to the present invention preferably represents
from 5% to 35% by weight of the total composition.
The compositions according to the invention preferably
comprise enzymes. Suitable enzymes for use herein are
protease, lipases, cellulases and amylases and mixtures
thereof. The compositions according to the present
invention may also comprise an enzyme stabilizing system.
Any conventional enzyme stabilizing system is suitable for
use herein, and preferred enzyme stabilizing systems are
based on boric acid or derivatives thereof, 1,2-
propanediol, carboxylic acids, and mixtures thereof.
The compositions herein can contain a series of further,
optional ingredients. Examples of the like additives
include solvents, alkanolamines, pH adjusting agents, suds
regulants, opacifiers, agents to improve the machine
compatibility in relation to enamel-coated surfaces,
perfumes, dyes, bactericides, brighteners, soil release
agents, softening agents and the like. Some of these
ingredients are believed to have an effect on the color
alteration problem underlying the present invention,
particularly perfumes and alkanolamines.
The compositions according to the present invention can be
formulated as conventional liquid detergent compositions
or, as an alternative as so-called "concentrated" liquid
detergent compositions, i.e. liquid detergent compositions
comprising less than 30% by weight of water.
W O 93/09215 P(~r/US92/09387
2122986 10
Exam~les
The following compositions are made which illustrate the present
invention. Compositions I-IV and VIII are concentrated liquid
detergent compositions.
I II III IV
% % % %
Alkyl benzene sulfonic acid 15 13 18 16
Na Coconut Alkyl sulfate 4 5 2
C13-15 alcohol 7 ethoxylated 13.4 15 13.5 13
Coconut alkyl sulfate 3 - - - 3
ethoxylate
Coconut N-methlyl glucosamide
Coconut fatty acid 11 4 8.5 7.5
Dodecenyl succinic acid 6 8 7 6
Citric acid 5.5 5.9 6 5
Tartrate momo succinate
Diethylene triamine 0.9 0.9 1.1
pentamethylene phosphonic acid
Ethanol 1.5 1.5 3
Propandiol 9.5 8.8 9 6
Monoethanolamine 8 12.5 14
Triethanolamine - - - 15
Sodium metaborate 2 2 2
Sodium pyrosulfite 0.05 - - 0.01
Sodium sulfite - 0-075
Potassium bisulfite - - 0.1
Sulfur dioxide
Enzymes 0.8 0.8 1.2 0.8
Perfume 0.5 0.5 0.6 0.5
Dyes 2Sppm - 25ppm 25ppm
Sodium (potassium)hydroxide:to pH 7.5 7.5 7.5 7.5
Water and minors ------- to 100
W O 93/09215 2 1 2 2 9 ~ ~ PC~r/US92/09387
11
V VI VII VIII IX
% % % % %
Alkyl benzene sulfonic acid 10.4 10.2 12 - -
Na Coconut Alkyl sulfate 2.5 2.8 2
C13-15 alcohol 7 ethoxylated 9.2 11.6 8.5 5 3
Coconut alkylsulfate 3 - - - 20 13
ethoxylated
Coconut N-methlyl glucosamide - - - 11 6
Coconut fatty acid - 12 - 8 5
Dodecenyl succinic acid 6 - 10.5 3
Citric acid 8 - 3.5 5 2
Tartrate momo succinate - - - - 3
Diethylene triamine 0.7 0.7 0.5 0.5 0.5
pentamethylene phosphonic acid
Ethanol 4 7 4 4 4
Propandiol 4.5 1.5 2 6 3
Monoethanolamine - - - 5 2
Triethanolamine - 6.5 - - 2
Sodium Metaborate 1 - 2 2
Sodium pyrosulfite - 0.02 - 0.05
Sodium sulfite - - 0.01
Potassium bisulfite - - - _ 0.03
Sulfur dioxide 0.01
Enzymes 0.8 0.5 0.5 1 0.7
Perfume 0.5 0.4 0.3 0.5 0.3
Dyes 25ppm lOppm 15ppm - 25ppm
Sodium (potassium)hydroxide:to pH 7.5 7.5 7.5 7.5 7.5
Water and minors ---- to 100 ____ ____
W O 93/09215 PC~r/US92/09387
2122986 12
Ex~erimental Part
The following composition was made:
Alkyl benzene sulfonic acid 15.2
MEA Coconut Alkyl sulfate 4
C13-15 alcohol 7 ethoxylated 13.4
Coconut alkyl sulfate 3 ethoxylate
Coconut N-methyl glucosamide
Coconut fatty acid 8.5
Dodecenyl sussinic acid 6.9
Citric acid 5.9
Tartrate mono succinate
Diethylene triamine pentamethylene O.9
phosphonic acid
Ethanol 1.5
Propandiol 8.8
Sodium hydroxide
Potassium hydroxide 0.25
Monoethanolamine 12.5
Triethanolamine
MEA Metaborate 2
Enzymes 0.8
Perfume 0.5
Opacifier 1.2
Acid blue 80 25ppm
Acid blue 7 14ppm
Water and minors to 100
The color of this composition was defined immediately after
it was made by measuring its Hunter parameters (L,a and b
values). Therafter, one sample (sample 1) of this
composition was supplemented with 1000 ppm sodium
pyrosulphite and stored for two weeks at room temperature.
WO93/0921~ 2 1 2 2 ~ 8 6 PCT/US92/09387
13
Another sample (sample 2= Ref) of the composition above was
also stored in the same conditions without any color
stabilizer being added. After two weeks, the Hunter
parameters of the two samples were measured. Results were
as follows:
Fresh After two weeks storaqe
samPle 1 samPle 2 =
ref
L 37 37 36
a -9 -9 -12
b -22 -23 -12
Appearance Blue Blue Green
Conclusion:
After two weeks storage at room temperature, the color of
the sample without any color-stabilizing system according
to the present invention already differs substantially from
the color of the fresh product, whereas the color of the
sample comprising a color stabilizing system according to
the present invention is virtually unchanged; a difference,
if any, is certainly not visually detectable.
