Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
10449~3
Background of the Invention
Field of the Invention
This invention relates to concentrated heavy
duty liquid compositions for use in cool water fabric
laundering. Such compositions contain a nonionic surfactant
component, an anionic surfactant component and an alkanol-
amine component.
More particularly the invention concerns the use
of narrowly defined primary alcohol ethoxylates having
the ability to remove soils from fabrics which also provide
adequate suds during the wash and easy rinsing after the
wash.
In formùlating a liquid detergent composition
for consumer use it is important to provide a formulation
whose sudsing behavior is similar to the granular
.~ ,
~L
33
products customarily used by the consumer i.e., good sudsing
during the wash and low suds in the rinse. Nonionics are
generally known as low foamers whose foam is persistent at low
concentrations even though they do not foam freely at higher
concentrations. Under these conditions, the housewife will
tend to overuse product to get the desired suds level during
the wash and have to contend with a persistent foam during the
rinsing operation. These problems may be particularly impor-
tant when washing and rinsing at ambient temperature which is
the normal practice in some countries, which is desirable for
modern fabrics, and which has been suggested as an energy
conservation measure.
Prior Art
Heavy duty liquid detergent compositions are well
known in the art. Usually such compositions (see, for example,
U.S. Patents 2,908,651; 2,920,045; 3,272,753; 3,393,154; and
Belgian Patents 613,155 and 6Ç5,532) contain a synthetic
organic detergent component which is generally anionic, non-
ionic, or mixed anionic-nonionic in nature; an inorganic
builder salt; and a solvent, usually water and/or alcohol.
These compositions frequently contain a hydrotrope or sol-
ubilizing agent to permit the addition of sufficient quantities
of surfactant and builder salt to provide a reasonable volume
usage/performance ratio. While such liquid detergent composi-
tions have been found effective for some types of home
laundering, the presence of inorganic builder salts in such
compositions may be undesirable from an ecological standpoint
in improperly treated sewage.
Several attempts have been made to formulate builder-
free~ hydrotrope-free liquid detergent compositions. For
example, U.S. Patent 3,528,925
491~3
discloses substantially anhydrous liquid detergent com-
positions which consist of an alkyl aryl sulfonic acid,
a nonionic surface active agent and an alkanolamine
component. U.S. Patent 2,875,153 discloses liquid detergent
compositions containing a nonionic surfactant component
and a sodium soap component. U.S. Patent 2,543,744
discloses a low-foaming dishwashing composition comprising
a nonionic, water-soluble, synthetic detergent and a water-
soluble soap in the form of an alkali metal, ammonium or
amine salt. All of these detergent compositions are
effective for certain types of washing operations, but
none of the commercially available compositions of this
kind are highly effective both as pretreatment and heavy
duty washing agents for cleaning both natural and
synthetic fabrics.
U.S. Patent 3,663,445 relates to liquid cleaning
and defatting compositions containing a nonionic sur-
factant, an alkanolamine-neutralized anionic surfactant
and alkanolamine.
Collins, Canadian Patent 992,835 issued July
13, 1976, relates to detergent mixtures comprising a
high ratio of nonionic to anionic surfactant and free
alkanolamine.
Collins et al, Canadian Patent 1,020,039 issued
November 1, 1977, teaches that certain ethylene oxide-based
nonionic surfactants can be used at high concentrations in
liquid detergent compositions, in combination with alkanol-
amines and certain anionic surfactants, and without the
need for fatty acid-based stabilizers.
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U.S. Patents 3,709,838; 3,697,451; 3,55~,916;
3,239,468; 2,947,702; 2,551,634; British Patents 900,000;
842,813; 759,877; and Canadian Patent 615,583 disclose a
variety of detergent compositions containing mixed nonionic-
anionic surfactants, both with and without alkanolamines.
As can be seen from the foregoing, a substantial
effort has been expended in developing low-built and builder-
free detergent compositions in liquid form. Yet, there are
several problems associàted with the art-disclosed compositions
which render them less than optimal for wide-scale use.
First, the prior art is particularly concerned
about liquid compositions suitable for fabric cleaning and
has not been concerned with formulations that give satisfactory
suds during the wash and whose suds are easily broken down
during the rinsing operation.
Second, many of the prior art compositions contain
phosphorus-based builder materials. Such builders, and
compositions containing same, may not be useful in areas of
the country having improperly treated sewer~age effluents.
Third, many of the prior art compositions are
formulated at too low a ratio of nonionic:anionic surfactant
to provide optimal oil~ soil removal from fabrics.
Finally, many of the prior art compositions are
formulated to provide satisfactory through-the-w`ash fabric
cleaning performance, but do not provide good pre-wash
treatment of oily soil iound in collars and
.____ _ .. . . . .. . ., . ~ .. .. ..
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cuffs of fabrics. Most users of liquid laundry detergent
compositions expect that superior fabric cleansing can be
secured by applying the liquid product directly, at Eull
strength, to heavily soiled areas of the fabric prior to
laundering. Accordingly, it is desirable t:o provide a
liquid detergent having good pre-treatment cleaning
benefits as well as good through-the-wash cleaning per-
farmance.
It is an object of this invention to provide
builder-free, liquid detergent compositions having good
pre-wash and through-the-wash fabric cleaning which also
suds satisfactorily during the wash and can readily be
rinsed away during the rinsing operation.
SUMM~RY OF THE INVENTION
The present invention provides liquid detexgent
compositions comprising (a) from about 20~ to about 50%
by weight of a nonionic surfactant produced by the
condensation of from about 2 to about 15 moles of ethylene
oxide with one mole of a primary alcohol having a straight
or branched alkyl chain having 8 to 12 carbon atoms, said
nonionic surfactant being further characterized by an HLB
(hydrophilic-lipophilic balance) of from about 8 to abou~
17, preferably 9.0 to 13.5 and especially preferred 9.5
to 12, and a CMC from about 0.006 to about 0.10, preferably
0.008 to 0.05, weight percent, at 25C; (b) an anionic
surfactant which is an alkanolamine salt thereof, wherein
the anionic portion is selected from the group consisting
of alkylbenzene sulfonic acids having from about 9 to about
15 carbon atoms in the alkyl group, alkyl sulfuric acids
ha~ing the formula ROSO3H wherein R is an alkyl, straight
or branched chain, of about 12 to 16 atoms and mixtures
-- 5 --
49~3
thereof, and wherein the alkanolamine is a member selected
from the group consisting of monoethanolamine, die~hanol-
amine, triethanolamine and mixtures thereof, and wherein
the weight ratio of nonionic surfactant to anionic sur-
fac~ant is from about 1.8:1 to about 8.0:1 based on the
free acid form of the anionic surfactant; and (c) at
least 1~ by weight of the composition of free al~anolamine
which is a member selected from the group consisting of
monoethanolamine, diethanolamine, triethanolamine and
mixtures thereof.
_TAILED DESCRIPTION OE' THE INVE NTION
The individual components of t~le instant liquid
detergent compositions are described in detail below.
THE NONIONIC SURFACTANT
The compositions o~ this invention contain as
an essential ingredient about 20% to about 50%, preferably
from about 25% to about 40%, by weig~t of a nonionic sur-
factant derived by the condensation of ethylene oxide
with a primary alcohol. The general formula for the non
ionic surfactant is CnH2n~lO(CH2CH2O)eH-
appreciated that the molecule consists of a lipophilic
portion derived from the alcohol and a,hydrophilic portion
derived from the ethylene oxide. The subscript e
refers to the number of moles of ethylene oxide condensed
with one mole of alcohol and can be defined as ethoxylate
number. The ethoxylate number may refer to the number of
moles of ethylene oxide condensed in a single species, i.e.,
a pure compou~d, but for commercial materials it represents
an average.
In the lipophilic portion of -the molecule n is
the number of carbons in the alkyl chain of the primary
alcohol precursor and is defined as carbon number. For this
invention the carbon chain of the aloohol may ~e strai~lt or branched.
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983
Examples of suitable primary straight chain alcohols
are the linear primary alcohols obtained from the hydrogenation
of vegetable or animal oil fatty acids such as coconut, palm
kernel and tallow fatty acids, or by ethylene build-up
reactions (Ziegler process) and subsequent hydrolysis of the
terminal double bond. Preferred alcohols are n-nonyl, n-decyl
and n-undecyl and mixtures thereof. Suitable commercially
available ethoxylated alcohols are sold under the trademark
"Alfonic" by Conoco Chemicals, Continental Oil Company~
Saddlebrook New Jersey.
E~amples of suitable primary branched chain alcohols
are those obtained from the well known O~o process in which
linear olefins are reacted with carbon monoxide and hydrogen
to produce aldehydes which are then hydrogenated to giv0
alcohols. Both linear and branched chain alcohols are formed.
Commercially available ethoxylates made from these alcohol
blends suitable for this invention are marketed by Royal Dutch
Shell N.V. under the trademarks "Dobanol" and "Neodol".
The suitable ethoxylated alcohols which enable the
formulation of liquid de~ergent compositions for cool water
washing having good suds in the wash are shown to contain 2
to 15 moles of ethylene oxide and have an HLB range between
8.0 and 17.0 preferably between 9 and 13.5 and especially
preferred between 9.5 and 12. As will be seen in Tables I
and IV and Figure 1 those formulations whose nonionic component
has an HLB of 8 to 17 have generally good to intermediate
suds in the wash. Those formulations within the preferred
HLB range have generally good suds in the wash. The one
sample (#9-n=15,e=7) that is within the preferred HLB range
but is not satisfactory in suds in the wash is outside the
scope of the invention; it does not satisfy the good rinsing
~04~83
requirement which is discussed hereinafter.
The HLB refers to the hydrophilic - lipophilic
balance of the nonionic which is a widely accepted measure
of the polarity of a surfactant and its relative affinity
for aqueous or hydrocarbon media. Developed originally by
W. C. Griffin (J.Soc. Cosmetic Chemist Vo:L. I, p. 311, 1949)
the concept permits numerical values to be given to surfactant
materials, the scale being such that hydrophilicity increases
with increase in HLB value. The HLB of the nonionic surfactants
herein can be experimentally determined in well-known fashion r
or can be calculated in the manner set forth in Decker,
"Emulsions Theory and Practice" Reinhold (1965), pp. 233
and 248. For example, the HLB of the nonionic surfactants
herein can be simply approximated by the term
~LB = 51[weight percent of ethylene oxide in the molecule].
As indicated by this formula, the HLB will vary, for
a given alcohol chain length, with the amount of ethylene
oxide present in the molecule. This is shown in more detail
in Figure 1 which was constructed by pLotting the calculated
HLB'S of alcohol ethoxylates and drawing lines to connect
those alcohol ethoxylates having the same HLB.
A second requirement for the nonionic surfactants
suitable for this invention is that subsequent to the wash
they exhibit good rinsing~ Nonionic surfactants fitting this
requirement are shown to have a critical micelle concentration
(CMC) of between about 0.006 and about 0.1 weight percent,
preferably between 0.008 and 0.05 weight percent in water,
provided that the carbon number of the alcohol portion is 8
to 12. The CMC refers to the saturated concentration of
nonionic surfactant as singly dispersed species in water.
When additional surfactant is added to such a solution the
1~4D~9~3
additional molecules do not disperse as single species but in
dispersing form micelles. This is a well recognized phenomenon
in the study of solutions of surface active agents.
Referring now to Tables I and IV and Figure 2, it
will be seen that good rinsing was obtained for those com-
positions containing an ethoxylated alcohol having a carbon
number of 8 to 12 and a CMC between about 0.006 and about 0.1%,
preferably 0.008 to 0.05% by weight. The CMC's presented on
Figure 2 were derived from the data given in "Nonionic
Surfactants" Vol. 1, Marcel Dekker, Inc., N.Y. (1967),
M. J. Schick, editor, Table 15.3 pp. 482-486. The CMC data
used for Figure 2 were all determined by the surface tension
method at 23-25C. The CMC data in Table 15.3 are given in
~-moles per liter but were converted to weight percent in
constructing Figure 2 which shows a series of constant CMC
lines as the carbon number and the ethoxylate number of the
molecule vary. It will be noted that the sample having
n=15,e=3, while having desirable suds in the rinse character-
istics, is not within the scope of the invention because this
sample does not fall within the HLB limit~ needed for good
suds in the wash; i.e., the n=15,e=3 sample has low suds in
the rinse because it is a very low sudser in the wash. The
n=11,e=12 sample is satisfactory in rinse suds and intermediate
in wash sudsing. The sudsing of this sample in~the wash can
be made satisfactory without affecting rinse suds by increasing
the anionic level in the formula (see Table V).
It should be noted that the CMC requirement applies
to the nonionic component of the formulation whether it is a
pure component or a mixture of different carbon numbers and/or
ethoxylate numbers.
As has been noted, formulations with good sudsing in
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the wash and good rinsing require a nonionic component having
a partiaular range of CMC values and carbon numbers. The
upper c~a limit serves to define nonionics having a low
enough CMC to provide good suds in the wash. It will be
appreciated that for good sudsing in the wash, the concentration
of the nonionic in the wash solution must exceed the CMC of
the nonionic. The upper CMC limit and lower carbon number
limit also serve to eliminate those materials which have an
appreciable odor intensity which can be a problem in formulating
compositions having little odor or in which it is desired to
add perfume. The lower CMC and upper carbon number limits
define nonionics having good rinsing characteristics; i.e.,
they exclude nonionics which have persistent suds in the rinse.
It has been discovered that stripping of the nonionic
surfactant after ethoxylation, i.e., removing some or all of
unethoxylated alcohol, improves detergency. This is described
in Collins' concurrently filed copending application,
entitled "DETEROENT COMæOSITION", Attorney's Docket Number
P&G 2063. Stripping however, is not a factor in achieving
0 the suds characteristics of this invention.
THE ANIONIC SURFACTANT
The anionic component of the instant detergent
compositions is a high sudsing alkanolamine salt of an
organic anionic acid surfactant. Suitable examp`les include
alkylbenzene sulfonic acids, alkyl sulfuric acid, esters of
fatty acids sulfonated in the alpha position, alpha olefin
sulfonic acids, and mixtures thereof. The alkanolamine
anionic salts are prepared by neutralizing the anionic
sulfuric or sulfonic organic acid with an alkanolamine
selected from the group consisting of monoethanolamine,
diethylanolamine, triethanolamine and mixtures thereof.
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The triethanolamine salts are preferred herein. The-anionic
surfactant salt is employed herein in a quantity sufficient
to provide a weight ratio of nonionic surfactant to a~ionic
surfactant of from about 1.8:1 to abou~ 8.0:1, preferably at
a ratio of 2.5:1 to 5.0:1, based on the free acid form of
the anionic surfactant.
For example, the alkanolamine alkylbenzene sulfonate
herein preferably consists of a mono-, di- or tri-ethanolamine
salt of a straight or branched chain alkylbenzene sulfonic
acid in which the alkyl group contains from about 9 to about
15 carbon atoms. Especially preferred surfactants of this
type are those in which the alkyl chain i5 linear and averages
about 11 to 12 carbon atoms in length. Examples of alkanolamine
alkylbenzene sulfonates useful in the instant invention include
monoethanolamine decylbenzene sulfonate, diethanolamine
undecylbenzene sulfonate, triethanolamine dodecylbenzene
sulfonate, monoethanolamine tridecylbenzene sulfonate,
triethanolamine tetradecylbenzene sulfonate, and diethanol-
amine tetrapropylenebenzene sulfonate, and mixtures thereof.
Examples of cornmercially available alkylbenzene sulfonic
acids useful in preparing the
83
alkanolamine sulfonates of the instant invention include
Conoco~ SA 515jSA 597 and SA 697, all marketed by the Con-
tinental Oil Company, and Calsoft ~ LAS 99~ marketed by
the Pilot Chemical Company.
The alkanolamine alkyl sulfate herein consists of
a mono-, di- or tri-ethanolamine salt of an alkyl sulfuric
acid reaction product having the formula ROS03H wherein
R is an alkyl, straight chain or branched chain, of about
8 to 18 carbon atoms. Th`e alkyl sulfuric acid reaction
product is made by reacting sulfuric acid with a monohyclric
alcohol having about 8 to 18 carbon atoms. Preferably R
has 12 to 16 carbon atoms.
Another anionic detergent useful herein is the
ethanolamine salt o an alpha sulfonated fatty acid.
These materials have the formula
H O
11
Ri -- C - C -- O -- R2
S03X
wherein X is selected from the group consisting of .nonG-
ethanolamine, diethanolamine, triethanolamine and mixtures
thereof; Rl is an alkyl chain of from about 6 to about 20
carbon atoms ~forming with the two carbon atoms a fatty
acid group); and R2 is an alkyl chain, the sum of the carbon
atoms in Rl and R2 being from about 13 to about 23 carbon
atoms. Specific examples of this class of compounds include
esters wherein R2 is methyl, ethyl, propyl, butyl, hexyl
and octyl groups and the fatty acid group (Rl plus the two
carbon atoms in the structure above) is lauric, myristic,
palmitic, stearic acids and mixtures thereof.
Yet another anionic detergent useful herein
consists of a mono-, di- or tri-ethanolamine salt of
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10~49~3
alpha olefin sulfonic acids and mixtures thereof. The
sulfonation of alpha olefins and the compositions resulting
therefrom are described more fully in U.S. Patent 3,332,880
of Phillip F. Pflaumer and Adriaan Kessler, issued July
Z5, 1967, titled DETERGENT COMPOSITION.
The Alkanolamine
A third essential component of the liquid
detergent composition of the present invention is the
alkanolamine compound. The alkanolamine useful herein is
selected from the group consisting of monoethanolamine,
diethanolamine, triethanolamine, and mixtures thereof.
Mixtures of these three alkanolamine compounds are produced
by the reaction of ethylene oxide with ammonia. The pu e
compounds can be separated from this mixture by stanclard
distillation procedures.
The alkanolamine component of the present
invention serves two purposes. As will be discussed
more fully hereinafter, in the preferred method for
preparing the instant compositions the alkanolamine
Z0 neutralizes the free acid form of the anionic surfactant
to provide the corresponding alkanolamine salt which is
an essential component of the instant detergent compositions,
In addition, the excess alkanolamine beyond that necessary
to form the anionic surfactant salt contributes to detergency
performance and serves as a buffering agent which maintains
wash
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.~ .
4t9~3
water pH of the instant compositions within the range from
about 7 to about 9. It is essential that the compositions
of this invention contain at least 1~ by weight of the
total composition of free alkanolamine, i.e., an excess over
that needed to neutralize the alkylbenzene sulfonic acid
anionic surfactant.
Stable liquid ~etergent compositions containing
nonionic, anionic and alkanolamine components can be for-
mulated by preparing each component separately and thoroughly
mixing them together in any order. In a preferred method for
preparing the instant compositions, the anionic and alkanol-
amine components are formulated simultaneously by over-
neutralizing the alkylbenzene sulfonic acid with alkanolamine.
This method forms the requisite alkanolamine alkyl benzene
sulfonate and provides the free alkanolamine component of the
instant composition. Preferably, the compositions contain
from about 2.0% to about 15.0~ by weight of free alkanolamine,
most preferably triethanolamine.
Optional Components
Although the liquid detergent compositions of the
instant invention need only contain the above-described three
components (i.e., thick, anhydrous compositions), highly
preferred compositions herein contain, in addition to the
three active components, a solvent selected from`the group
consisting of water and water-alcohol mixtures. Such solvents
can be employed to the extent of from about 1% to 45% by
weight of the total detergent composition. In preferred
compositions the solvent comprises from about 25% to 45% by
weight of the total composition. Use of such solvents in the
compositions herein has several advantages. First, the
physical stability of the detergent compositions can be
9~3
improved by dilution with such solven-ts in that clear points
Gan thereby be lowered. The diluted compositions do not
cloud at the low temperatures which are commonly encountered
during shipping or storing of commercially marketed detergent
compositions.
Secondly, addition of solvents, especially water-
alcohol mixtures, serves to regulate the gelling tendency
which liquid detergent compositions of the instant type
exhibit upon dilution with water.
When an alcohol-water mixture is employed as a
solvent, the weight ratio of water to alcohol preferably
is main-tained above about 3:1, more preferably from about
4:1 to about 7:1. ~liyh alcohol (particularly e-thanol)
concentrations in the water-alcohol mixtures used in the
instant invention are preferably avoided because of
flammability problems which may arise at such higher alcohol
levels.
Any alcohol containing from 1 to about 5 carbon
atoms can be employed in the water-alcoho:L diluent used to
prepare the instant detergent compositions. Examples of
operable alcohols include methanol, ethanol, propanol,
isopropanol, butanol, isobutanol, and pentanol; ethanol is
highly preferred for general use.
A second optional component which can be added to
the detergent compositions of the instant invention is an
electrolyte salt. As pointed out in U.S. Patents 2,530,173
and 3,440,171, electrolyte salts lessen the gel formation
which tends to occur with alkanolamine-neutralized surfactants.
Such electrolytes, when used herein in combination with a
water-alcohol solvent at a weight percent of the total com-
position of from about 0.2% to 5% of said electrolyte salt,
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491~3
substantially eliminate gelation of the anionic surfactant
without the need for excessively high alcohol levels.
Operable electrolyte salts include the alkali metal
chlorides, sulfates and carbonates, and the salts formed
from the reaction of alkanolamines with inorganic acids, e.g.
HCl, H2SO4, and organic acids such as formic, acetic, propionic,
butyric and citric acid. Specific examples of such salts
include sodium chloride, potassium chloride, sodium carbonate,
potassium carbonate, potassium sulfate, sodium sulfate, tri-
ethanolamine sulfate, triethanolamine citrate, triethanolamineacetate, triethanolamine formate, monoethanolamine proprionate
and diethanolamine butyrate. Of all the possible electrolyte
salts useful to prevent gelation of the compositions herein,
potassium chloride is highly effective and pre~erred. Potassium
chloride is preferably added to the instant compositions to
the extent of from about 1~ to 3% by weigh-t to provide its
anti-gelling effects.
As noted, the employment of a solvent and electrolyte
serves to control and regulate gel formati~n in the instant
liquid detergent compositions. If, however, gel formation
is desired, it is possible to select particular concentrations
of a water solvent which yield gelled compositions in the
absence of alcohol and electrolyte salt. Thus, compositions
containing the three active components in the above-specified
concentrations and a water solvent comprising from about 15%
to 35~ by weight will be thick or gelled compositions,
provided no alcohol or electrolyte is present.
Other optional, non-essential, non-interfering
components can be added to the instant compositions to
provide improved performance or aesthetic appeal. Preferred
compositions of the invention are those to which a color
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L9~33
stabilizing agent such as citric acid has been added. These
compositions exhibit surprising stability against the tendency
of such compositions to develop a reddening upon storage. In
addition, the presence of citric acid in the compositions of
the invention has a beneficial effect from the standpoint of
preventing the development of the stains observed on the outer
surfaces of plastic bottles and occasioned by spillage,
seepage or handling of bottles with hands previously contacted
with the compositions of the invention. As with the anionic
surfactant acids, the citric acid forms alkanolamine citrate
when added to the instant compositions containing excess
alkanolamine. For convenience however, this alkanolam:ine
citrate concentration ln the compositions is expressed as a
weight percentage of the free acid form of the citrate, i.e.,
citric acid, added to the compositions. An amount of citric
acid of up to about 1~ by weight of composition is generally
added to obtain these color benefits. A highly preferred
range for the added citric acid is from about 0.05% to
about 0.30~ by weight of composition. Of course, the com-
positions must still be formulated to maintain the minimumof about 1% (wt.) of free alkanolamine.
Suds suppressing agents can be present in the instant
compositions in minor proportions to provide lower foaming
products. While the compositions herein inhere~tly provide
adequate suds levels during the wash and good rinsing after
the wash, some users desire lower sudsing products for the
washing cycle which also improves rinsing. Accordingly, the
compositions herein can optionally contain from about 0.5% to
about 3% by weight of fatty acids as suds suppressing agents.
Useful fatty acids for this purpose consist of those fatty
acids containing from about 8 to about 24 carbon atoms and
'
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9~3
preferably from about 10 to about 20 carbon atoms. Suitable
fatty acids can be obtained from natural sources such as, for
example, plant or animal esters (e.g., palm oil, coconut oil,
babassu oil, soybean oil, safflower oil, tall oil, castor oil,
tallow, whale and fish oils, lord, grease and mixtures thereof).
The fatty acids also can be synthetically prepared (e.g., by
the oxidation of petroleum or by hydrogenation of carbon
monoxide via the Fischer-Tropsch process). Examples of
preferred fatty acids for use as suds suppressing agents are
those derived from coconut oil, olein and tallow. It should
be understood that the fatty acid suds suppressor, while added
as the acid in making the composition, will exist as the
alkanolamine salt of the fatty acid in the composition because
of the requirement that there be at least 1~ by weiyht oE free
alkanolamine in the composition.
Other optional components include brightne~s,
bluing agents, fluorescers, enzymes, bleaching agents, anti-
microbial agents, corrosion inhibitors and coloring agents.
Such components preferably comprise no more than about 3~ by
weight of the total composition.
Utilization of nonionic surfactant to anionic
surfactant (free acid basis) ratios of from about 1.8:1 to
about 8.0:1 in combination with utilization of excess free
alkanolamine is important to formation of detergent compositions
having good cleaning performance and good stability character-
istics of the instant invention. Formation of mixed surfactant
micelles, which results from employment of the particular
nonionic-anionic surfactant ratio of the instant invention,
provides good detergency performance which is insensitive to
water hardness.
Employment of alkanolamine salts and excess
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alkanolamine also contributes to the ef~ec-tiveness of the
instant detergent compositions. For example, these com-
positions containing the alkanolamine counterion in
combination with excess free alkanolamine are superior
in cleaning polyester/cotton than corresponding com-
positions containing the more conventional sodium or
potassium salts of the anionic surfactant acids and no
free alkanolamine. Of the alkanolamines, triethanolamine
is preferred herein from the sta~dpoint of availability
and cleaning efficiency.
The compositions of the instant invention are
also designed to provide good cleaning benefits when
used in either of the two modes commonly employed with
liquid detergent compositions. First, the compositions
herein can be used as pre-treatment agents which are
applied in concentrated form directly onto fabric stains
prior to fabric washing. Second, the instant compositions
are also useful as detergents for conventional through-
the-wash fabric laundering operations. Good stain
removal and soil removal are attained when the instant
compositions are dissolved in an aqueous washing solution
at a concentration of at least about 0.10% by weight
~approximately 30 grams per 30 liters of wash water.)
For through-the-wash fabric laundering, a concen~tration
of the instant compositions in the range of from 0.08%
to about 0.20% by weight of the laundering liquor is
preferred. Of course, this can be adjusted, depending
on the soil load and the desires of the user.
With regard to pre-treatment efficacy, the
instant compositions containing the herein specified
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3 ~44~B3
componen-ts and component ratios provide oily stain
removal from polyester or polyester/cotton fabrics
which is superior to similar pre treatment performance
attained by utilization of conventional built anionic
detergent compositions and which is, in fact, com-
- parable in oily stain removal with that attained with
pure nonionic surfactan-ts which are known to be par-
ticularly useful in such pre-treatment stain removal.
Through-the-wash detergency performance of the instant
compositions is, in fact, comparable with that attained
with conventional built granular anionic detergent
compositions.
The following examples illustrate the liquid
detergent compositions of the instant invention.
EXAMPLES
Laundry Procedure
Several formulations were evaluated for sudsing
characteristics during washing and after the rinsing
operation. The procedure consisted of filling the
wash tub with water, adding the product, agitating
for 1 minute to dissolve the product and then adding
a load of naturally soiled clothes. After the clothes
were washed they were removed from the wash tub and
extracted to remove some of the washing solution~.
The washing solution in the tub was drained off, the
tub rinsed and then filled with water. The extracted
clothes were then added back to the wash tub and
rinsed with agitation. During the rinse additional
water flowed into the tub and the overflow ran into
a pipe leading to the drain. Sudsing observations
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.
~o~
were made during the washing process, during the
rinsing operation and when the rinsing time allowed
was completed.
Washing machine - top loading semiautomatic;
impeller type with reversing
agitation; operated manually
during the rinse; has built
in extractor adjacent to the
wash tub.
10 Model - National NA6050
Manufacturer - MATSUSHITA DENKI SANGYO KK
Washing Machine Division
Osaka, Japan
Agitation - Normal spee~, reversing
Wash fill level - 30 liters
Water temperature - 21C (70F)
Water hardness - 0.79 grains/liter as CaCO
(3 gr/U.S. gal.)
Product usage ~ 35 grams
20 Fabric load - 1.2 kilograms of naturally
soiled clothes
Washing time - 10 minutes
Extraction - 2 minute spin
Rinse - 34 liters of water, as abovè,
10 minutes rinsing time with
normal speed reversing agitation;
during rinsing additional water
~ flows into the tub and the over-
; flow goes to the drain through
an overflow pipe.
9~)4~ 3
The sudsing characteristics of the t~st
products were judged by the following scale:
During t wash
(1) Suds cover may be present but is less
than 1 cm. in height.
(2) Suds cover is present but the suds
height falls in the 1 to 3 cm. range.
(3) Sudsing during the wash was similar
to Japanese granular products on the
cu~rent retail market. "Typical"
suds caver is about 3 to 6 cm.
Suds _ the rinse
(1) No suds in the rinse water or, if
present, collapse readily to yield
a clear solution with only traces
of very finely divided bubbles.
(2) Residual foam is present at low
level or that slight turbidity
persisted after agitation st~pped.
This grade defines a rinsing
character that is slightly poorer
than desired.
(3) Substantial or very persistent
suds observed in the rinse.
- 22 -
: Using the procedure outlined above several-liquid
compositions were tested for their suds characteristics.
The results observed are shown in the following table:
' ' .
.
- 23 -
. ~ 983
. ,~: ~ .. .
. ~ ~' ' - .
. ~ . ', . I
., ~, .
h X X X X X X X X ~ ~ ~1
~ ~ . ..
n c~
.
. . '' . ~ ~ .
ol u~ D r-
C~ o
o ~1 æ a)
, ~ ~ O ''' '' '' '' I '~ '' O O
Q ~ 2 ;
. u I
. ., , ',
. .
. . Ql '
x I J ~ ~ ~ ~ ~ ~ O~3
.
: ' .
133
Explanation of Table I
Description of Column Headings
A . Identification of alcohol lipophile:
(a) A mixture of linear primary alcohols
(5~ C8, 95% C10) ethoxylated with an
average of 3.0 moles ethylene oxide per
mole of alcohol, which was stripped under
vacuum (thereby removing most of the
residual unethoxylated alcohol, resulting
in an average ethoxylate number of 4.1).
(b) Alcohol derived from coconut oil.
(c) A mixture of linear primary alcohols
(5% C8, 95% C10) ethoxylated with an
average o~ 9.0 moles ethylene oxide per
mole of alcohol.
(d) Fatty alcohol derived from natural sources.
te) "Oxo" alcohol.
B,C. Carbon number is defined as the number of carbon
atoms in the alcohol lipophile. Colloidal
properties such as micellization, foaming and
detergency are well-known to be dominated, in
mixtures, by components having low critical
micelle concentration CMC. As shown on Figure
1, CMC is primarily a function of carbon number
among the lipophiles of this invention. Hence
the "dominant" carbon number is selected to be
distinctly above the average carbon number ~or
alllipophiles.
~. Ethoxylate number is defined as the average number
of moles of ethylene oxide condensed onto each
mole of alcohol lipophile.
- 25 -
E. Symbol "x" indicates the following liquid
detergent composition:
Composition Wt.
Nonionic (as indicated below) 33.0
Linear alkyl benzenesulfonic acid 11.0
(HLAS) (added as acid form but
neutralized with TEA during
making).
Triethanolàmine 11.0
Ethanol 5.0
KCL 2.5
Citric Acid 0.25
Brightener 0.~
Water (inc. optional color/perfume) Balance
100.0
Symbol "y" indicates a similar composition
where the HLAS usage has ~een increased from
11.0% to 16.5%, replacing water, and all
other usages remain the same. Symbol "~"
indicates a composition to which 2~ oleic
acid has been added, replacing water.
F,G. Sudsing is graded on a 3-point scale: "3"
signifies high suds; "2" signifies an inter-
mediate suds level; and "1" signifies low
suds. Sudsing in the wash and in the rinse
were graded on separate and relative scales.
It will be noted that "high" sudsing with
references to the rinse indicates a vastly
lower absolute level of suds than "high"
sudsing in the wash. Desirable properties are
"high" suds in the wash and "low" suds in the
rinse.
- 26 -
3t83
Examples 1, 10 and 11 are within the scope-of the
invention.
To help visualize the nonionics of interest, which
unexpectedly provide good sudsing in the wash and good
rinsing after the wash, Examples 1-11 are plot-ted (the
circled numbers) in Figures 1 and 2.
Using the above procedure, additional heavy duty
liquid detergent composi~ions containing ethoxylated alcohols
are tested. Table II summarizes the ethoxylates that are
used and the results that are obtained.
- 27 -
~044~8;~
.
.
h ~ ~, f~ ~ ~) ~ ~7
. . ' , ' .
I:Ll X X ~' X ~ X
. ' . ..
o o o o o u~ o 'i~
~ O
H .
O o o ~1 o o ~ O
~ . .' ' ,''' ~ .
~ ~ .
. O ~ ~1 ~1 0 ~ ~ O
I I O I I ~1 ~ 1 o
m
. .
. ''
. , '. ' ' ", .
~ .
_I . ..
~ ~ ~ ~r In \D 1~ CO ~ O
q
. ' ' '
, ~~~
,
.
~49~33
Symbols are the same as in Table I, plus "f"
that denotes the use of Ziegler fatty alcohol as the lipophile.
Examples 12-16 illustrate the good sudsing and
good rinsing results that are obtained when the ethoxylate
is within the preferred HLB range of 9.0 to 13.5 and the
preferred CMC range of 0.008 to 0.05.
Examples 17-23 illustrate the results that are
obtained when the ethoxylate is within the broad range of
8.0 to 15.0 for HLB and 0.006 to 0.10 for CMC.
Formulations are prepared with the nonionic
composition used in Example 1 to test the formula variations.
Table III summarizes the formulations that are prepared~
.
t ~ ~ - .
. .
~4~3
cn u~ o I o
U) ~ I
~ C~ o ~
co o ~I ~ I ~ n o c~ o o
CO o ~
' r~ D ~ ~1 0 0 0, I
a
CO
~D OCOI I I O ~ ~ O O
~ ~ .
.. ~ , ' ot~
Hu) O~1 1 1 1~`J O ~`I I I. ~ I
HN <`I~1 ~ o
O
Q'r ~ 1 I I t
~1) ' '
., ' ,; ~, ', . ~ ' ', '' .
a) .' u~
o ~ U ~
U
C.) . t~ . . . .
~ U
d O ~1 U
cn- u~ O
~ ~ X
CO o::~ . O
C) ~ 0 ~ U
d 1~1 0~ td- ~ t
O
N1~ ~ ~1
o~O ~1
o ~ q) u ~ u~
3 0
V ~ ~ O rl ~d 'd
~1 ~i X~W ~1 41 ~ 1 h
O O u
'Z ~ ) 0 (~1 ~ O (11
O U
P~ O rl O ~: X t2~ ~ rl ~ ~I ~ rl r-l h
~1 C) ,
3
,
. ~
. ... ..
9~3
For each of the above compositions, substantially
similar sudsing results in both the wash and the rinse are
obtained as for the compositions of Example 1. Detergency
for laundry pre-treatment is good and detergency through-the-
wash is in each case satisfactory.
Sudsing_Evaluation Using Artificial Soil
Several formulations were evaluated for sudsing
characteristics during the wash and rinsing after the wash
as hereinbefore described except for the following differences:
Product usage: 40 grams.
Fabric Load: 8 clean T-shirts (1.0 Kg.)
Artificial Soil Load: (added immediately after the Eabric
load) (a) Three 15x28 cm. muslin
swatches containing a total of 5.0
grams of organic soil as hereinafter
described and (b) 10 grams of
"inorganic" soil as hereinafter
described.
The artificially soiled swatches were prepared by
dissolving 5.0 grams of organic soil in 20 ml. of carbon
tetrachloride, allowing the solution to be absorbed by three
pieces of 15x28 cm. cotton muslin fabric and drying and
aging the swatches overnight in a fume hood. The organic
soil consisted of 1.0 grams of lactic acid and 4.0 grams of
synthetic sebum having the following composition:
9~3
- Palmitic acid 10~0%
Stearic acid 5.0
Oleic acid 15.0
Coconut oil 15~0
Olive oil 20.0
Squaline 5.0
Paraffin 10.0
Cholesterol 5.0
Spermaceti 15.0
100.O
The "inorganic" soil consisted of a mix-ture of 5.0
grams of bentonite clay, 4.0 grams of salt and 1.0 gramr, of
urea.
The sudsing characteristics of the compositions
tested using artificial soil were made using the washing and
rinsing procedure hereinbefore described. The formulations
tested and the results observed are given in Table IV.
~44~3
.. . ~,~
~ ~ ¦ N ~ O
.
. . ~ . '' ,~
~ -
. . 'P',~
ol X X x x x ~X ~ O ,~ 'x~
. ~ a
. rd ~
., . ~1 ~ ~ o O
~; X~ ~ ~J N
D¦ ~ 3
Rl l l l ¦ al O :
~ . Q 8 , R a a
r:~ . ~
q~ . o ~ o ~ I o~ 3
m o ~ ~ ,~
... ,,. . .~ .... u . . . ox'J
0 ~ ~ ¦ U l ~ r
~1 ' ~ O In
. ~ O ,~ f ~ h
.' . X .
--3
. . ~
Examples 31, 32, 33, and 35 are within the scope of the
invention. It will be noted that Example 33 was rated as slightly
less than satisfactory in sudsing during the wash. The sudsing
in the wash of Example 33 can be improved without effecting rinse
5 Suds by increasing the anionic level (see Table V).
To help visualize the nonionics of interest, which
unexpectedly provide good sudsing in the wash and good rinsing
after the wash, Examples 30-35 (numbers in square boxes) are
plotted in Figures 1 and 2.
Additional compositions are tested for sudsing character-
istics with artificial soil using the washing and rinsing procedure
hereinbefore described. TABLE V summarizes the compositions that
are tested and the results that are obtained.
34 -
~ u~
~ ¦ N N
S:~ .
~I) O X
a ~ .
~ l ~
a 8~
o ~i
m o ~ ~$ ~ o~
~ a
rl ~ ol a) o o a) ~
~ ~ r~ o~ ~ o
X ~
-35 ~
1~4~
Example 36, which is identical to Example 33 (Table IV),
is observed to have marginal to satisfactory sudsing during the
wash and satisfactory suds in the rinse. Example 37 is similar
to Example 36 except that the HL~S content is higher (16.5~ vs
11%). The effect of increasing the HLAS content in the composition
is seen to improve the sudsing characteristics during the wash and
to have no effect on the rinse characteristics following the wash.
Examples 36 through 39 are within 1:he scope of the in-
vention.
WHAT IS CLAIMED IS:
~ 36
