Note: Descriptions are shown in the official language in which they were submitted.
~:3~34
STABILIZED OIL-IN-WATER CLEANING MICROEMULSIONS
James Pyott JOHNSTON
John Richard WALKER
Ivan HERBOTS
TECHNICAL FIELD
The present invention relates to methods for ad-
justing the pH of carboxylic acid-containing oil-in-
water microemulsions towards the alkaline range using
a variety of nitrogen-functional ingredients such as
amines, quaternary ammonium salts and amine oxides.
Liquid laundry detergent compositions, liquid hard sur-
face cleaners, and the like, are thereby provided.
BACKGROUND
Various organic solvents, for example terpenes and
terpene-like compounds, are rather well-known for use
in hard surface cleaners for their grease removal abi-
lity. Such cleaners often contain 10%, or more, of a
solvent such as d-limonene, together with a surfactant,
especially nonionic surfactants which are also well-
known for their grease removal performance. Such
compositions have also been suggested for cleaning
carpets. British Patent 1 603 047, 1981. EPO applica-
tion 0 040 882 published December 2, 1981 discloses hard
surface cleaners comprising a mixture of benzyl alcohol,
terpenes, surfactants and other detersive ingredients.
.~ .
~1230534
-- 2 --
European Patent Application 0 072 488 (published
February 23, 1983) suggests that terpenes such as d-
limonene can be incorporated into fabric pre-treating
compositions as a non-homogeneous emulsion. Such
emulsions are apparently designed to be packaged in
relatively small volume containers which can be shaken
immediately prior to use to restore some semblance of
homogeneity, then dispensed directly onto fabrics by
spraying.
Clear emulsions comprising water, surfactant and
various other solvents are disclosed by Davidsohn in 3rd
International Congress of Surface Activity, Cologne (1960).
Terpineols, e.g. from pine oil, have been disclosed
for use in wet-scouring of textiles. In particular, in
1937, U.S. Patent 2.073.464 disclosed clear compositions
which can be prepared from pine oil terpineol such as
alpha terpineol and fatty acid soap or free acid neu-
tralized in situ to alkaline pH.
More recently, an article in Soap Perfumery Cosmetics
April 1983, pages 174, 175 suggests that only low levels
of terpenes (3%) can be incorporated into heavy duty
liquid detergents.
Citrus juices, which contain relatively low amounts
of terpenes, have been suggested for use in hand soaps
and dishwashing liquids. UOS. Patent 3.650.968; Memoire
descriptif 873,051 (relating to Brevet Anglais 53472/77,
22 December 1977).
The use of relatively high concentrations of sol-
vents in heavy duty liquid laundry detergents offers
many advantages. The liquid form of such products al-
lows them to be used as pre-treatment agents. When used
through-the-wash, solvents such as terpenes, certain
alkyl-aromatics and certain olefin hydrocarbon solvents,
have now been found to provide additional cleaning
benefits over and above those provided by detersive
~ 33 ~
surfactants. Unfo~tunately, the non-homog~neity of
compositions such as those disclosed in EPO 0 072 48a
makes them inconvenient for use as a general purpose
laundry deteryent, since most heavy duty liquid detergents
are packayed in relatively large containers which are
unhandy for the user to shake thoroughly.
The present ;nvention provides fully-formulated heavy
duty liquid detergent compositions comprisiny as much as
20%, and higher, by weight of essentially water-insoluble
solvent, in the form of homogeneous, fatty acid-built
liquids that are quite suitable for use in both the fabric
pre-treatment and through-the-wash laundry modes, as
hard-surface cleaners, and the like.
Importantly, means are disclosed which allows such
compositions to be formulated as stable microemulsions at
pH's above their "as is" formulation pH oE about 6.5
SUMMARY OF THE I~VENTION
The present invention encompasses means for adjusting
the p~ of an oil-in-water microemulsion typically
comprising a mixture of water (l0~ to 70%), grease--removal
solvent or solvent mixture (5~ to 20%), fatty acid or
fatty acid~soap mixture (5% to 35%) and detersive
surfactant (1% to 40%), together with optional detersive
ingredients (generally 0.1% to 15%), by admixing therewi-th
a nitrogen-functional material such as an amine, a
quaternary ammonium salt, or an amine oxide, whereby the
"as is" pH of said microemulsion is adjusted from its
original pH of around 5.5 towards a neutral or alkaline
pH, whereby the cleaning performance, especially enzyme
cleaning action, of said microemulsion i8 improved.
The invention also encompasses compositions prepared
in the foregoing manner, as well as methods of cleaning
fabrics and hard surfaces using said compositions.
~L230534
pETAILED DESCRIPTION OF T~E INVENTION
The essential solvent, fatty acid (or soap) and water
emulsification system, the detersive surfactant
components, the means for stabilizing the formulation at
pH~s above 6.5, and various other optional ingredients
used in the practice of the present invention are
described in more detail, hereinafter. All percentages
and ratios mentioned in this application are by weight,
unless otherwise stated.
Solvent - The solvents employed herein can be any of the
well-known "degreasing" solvents commonly known for use,
in, for example, the commercial laundry and dry-cleaning
industry, in the hard-surface cleaner industry and the
metalworking industry. Typically, such solvents comprise
hydrocarbon or halogenated hydrocarbon moieties of the
alkyl or cyclo-alkyl type, and have a boiling point well
above room temperature.
The formulator of compositions of the present type
will be guided in the selection of solvent partly by the
need to provide good grease-cutting properties, and partly
by aesthetic considerations. For example, kerosene
hydrocarbons function quite well in the present
compositions, but can be malodorous. Kerosene can be used
in commercial laundries. For home use, where malodors
would not be tolerated, the formulator would be more
likely to select solvents which have a relatively pleasant
odor, or odors which can be reasonably modified by
perfuming. Such solvents include, for example, the
terpenes and terpenoid solvents obtainable from citrus
fruits, especially orange terpenes and d-limonene. Benzyl
alcohol is another relatively pleasant smelling solvent
for use herein. Mixtures of orange terpene and benzyl
alcohol are especially suitable for removing certain types
of stains, e.g. marker ink, shoe polish, and dirty motor
Oil,
12305i~
- 5 ---
Accordinyly, one preferred class of solvents used
herein are the liqui~ para~ins, especially the "iso"
C10 paraffins and the mono- and bicyclic mono-terpenes,
i.e., those o~ the hydrocarbon class, which include, for
example, the terpinenes, limonenes and pinenes, and
rnixture thereo~. ~ighly pre~ecred rnaterials of this
latter type are d -limonene and the mixture of terpene
hydrocarbons obtained from the essence of oranges (e.g.
cold-pressed orange terpenes and orange terpene oil phase
ex fruit juice). Also use~ul are, for example, terpenes
such as dipentene, alpha-pinene, beta-pinene and the
mixture of terpene hydrocarbons expressed from lemons and
grape-fruit.
Another preferred class of solvents are the C6-Cg
alkyl aromatic hydrocarbons, especially the C6-Cg
alkyl benzenes, in particular, octyl benzene. Short--chain
alkyl benzenes (e.g. toluene) are not preferred herein due
to toxicity and odor problems, and longer-chain alkyl
benzenes have undesirable soil redeposition problQms.
especially when used to launder fabrics.
Still another preferred class of solvents are the
olefins having a boiling point of a~ least about 100C.
The alpha-olefins have no~ been found to possess excellent
cleaning properties and low, rather pleasant odors. The
compounds l-decene and l-dodecene are especially preferred
olefin solvents for laundry detergent use.
In a highly preferred mode, the relatively non-polar
solvents, such as paraffin, olefin, terpene or alkyl
benzene solvents mentioned above, are used in combination
with a more polar solvent such as, for example, benzyl
alcohol, n-hexanol, phthalic acid esters such as
dimethyl-, diethyl--(preferred), dipropyl- or
dibutyl~pththalate, or the "Carbitol" solvents such as
Butyl Carbitol (trade mark for 2-(2-butoxyethoxy)ethanol)
~L23Q~3~
to provide broad-spectrum cleaning of a variety of polar
and non-polar soils. Such mixtures will have a ratio of
non--polar:polar solvent in the range of lO:l to l:lO.
preferably 5:1 to 1:5, and most preferably have a bit more
non-polar than polar solvent, generally a ratio of 5:1 to
5:4, especially for fabric laundering.
The examples disclosed hereinafter describe various
other solvents which can be used in the present
compositions.
As will be seen from the following disclosure, various
conventional detergent ingredients are used herein at
conventional amounts and concentrations.
Importantly, in the formulation of li~uid detergents,
the solvents herein can be used in combination with
relatively high (15%-25%, and higher depending on solvent~
levels of fatty acid/soap, which provide an important
detergency builder function,
~3L23~;34
-- 7
Detersive Surfactants - The compositions of this
invention will typically contain organic surface-active
agents ~surfactants) to provide the usual cleaning benefits
associated with the use of such materials.
Detersive surfactants useful herein include well-known
synthetic anionic, nonionic, amphoteric and zwitterionic
surfactants. Typical of these are the alkyl benzene sulfo-
nates, alkyl- and alkylether sulfates, paraffin sulfonates,
olefin sulfonates, alkoxylated (especially ethoxylated) al-
cohols and alkyl phenols, amine oxides, ~-sulfonates of
fatty acids and of fatty acid esters, and the like, which are
well-known from the detergency art. In general, such
detersive surfactants contain an alkyl group in the Cg-Cl8
range; the anionic detersive surfactants can be used in the
form of their sodium, potassium or triethanolammonium salts
but it is to be understood that the presence of magnesium
cations in the compositions usually means that at least some
portion of the anionic surfactant will be in the magnesium
salt form; the nonionics generally contain from about 5 to
about 17 ethylene oxide groups. U.S. Patents 4 111 855 and
3 995 669 contain detailed listings of such typical deter-
sive surfactants. cll-cl6 alkyl benzene sulfonates, C12-C18
paraffin-sulfonates and alkyl sulfates, and the ethoxylated
alcohols and alkyl phenols are especially preferred in the
compositions of the present type.
The surfactant component can comprise as little as
1% of the compositions herein, but preferably the composi-
tion~ will contain 1% to 40% , preferably 10% to 4~% , of sur-
factant. Mixtures of the ethoxylated nonionics with anionics
such as the alkyl benzene sulfonates, alkyl sulfates and
paraffin sulfonates are preferred for through-the-wash
cleansing of a broad spectrum of soils and stains from fabrics.
Such surfactants and mixes typically have ~LB s of 20 and above.
534
Polyamlnes - Polyamine materlals are optional ingredients
in the present compositions by virtue of their ability to
co-act with the solvent to remove the solid material that is
present in many greasy stains (e.g., carbon black in motor
oil stain; clay and color bodies in cosmetic stain). It is
to be understood that the term "polyamines" as used herein
represents generically the alkoxylated polyamines, both in
their amine form and in their quaternarized form. Such
materials can conveniently be represented as molecules of the
empirical structures with repeating units:
t N - R t- Amine for~
x
dlXQXy
and
- R -~ ~ Quaternarized
I x form
alkoxy
wherein R is a hydrocarbyl group, usually of 2-6 carbon
atoms; R may be a Cl-C20 hydrocarbon; the alkoxy groups
are polyethoxy, polypropoxy, and the li~e, with polyethoxy
having a degree of polymerization of 2-30, most preferably
lO to 20; x is an integer of at least 2, preferably from
2-20, most preferably 3-5; and ~ is an anion such as
halide or methylsulfate, resulting from the quaternization
reaction. The anion X~ is of no particular consequence
to performance of the polyamine in the present context,
and is mentioned only for completeness in the above
formula.
The most highly preferred polyamines for use herein are
the so-called ethoxylated polyethylene imines, i.e., the
polymerized reaction product of ethylene oxide with ethylene-
imine, having the general formula:
~L~31~34
g
N--CH2--CH2----~--x
(E+O)y
wherein x is an integer of 3 to 5 and y is an integer of 10 to 20.
Polyamines typically will comprise at least about 0.2% of the
preferred comFositions herein, generally 0.5~-5%.
Other OFtional In~redients - The compositions herein can contain other
ingredients which aid in their cleaning performance. For example, it
is highly preferred that through-the-wash detergent o~npositions con-
tain a detergent builder and/or metal ion sequestrant. Com~ounds
classifiable and well-known in the art as detergent builders include
the nitrilotriacetates, polycartoxylates, c;trates, water-soluble
phosphates suc'n as tri-polyphosphate and sodium ortho- and pyro~
phosphates, silicates, and mixtures thereof. Metal ion sequestrants
include all of the a~ove, plus materials like ethylenediaminetetra-
acetate, the amino-polyphosphonates and phosphates (DEQUES~ and
a wide variety of other poly-functional organic acids and salts too
numerous to mention in detail here. See U.S. Patent 3 579.454 for
typical examples of the use of such materials in various cleaning
compositions. In general, the builder/sequestrant will comprise
about 0.5~ to 15% of the composition. Citrate is one of the most
~referred builders since it is readily soluble in the aqueous phase
of heavy-duty liquid detergent compositions. Such ingredients are
also useful in hard-surface cleaners.
A source of magnesium ions can be used in the compositions, to
assist grease removal. Besides magnesium hydroxide, water-soluble
salts such as magnesium chloride, acetate, sulfate, and the like,
can be used.
The laundry compositions herein also pre~erably contain
enzymes to enhance their through-the-wash cleaning perfor-
mance on a variety of soils and stains. Amylase and pro-
tease enzymes suitable for use in detergents are well-known
~Z3~53~
- 10-
in the art and in commercially available liquid and granular
detergents. Commercial detersive enzymes (preferably a
mixture of amylase and protease) typically function best at
pH above about 7 and are typically used at levels of
0.001% to 2%, and higher, in the present compositions.
Ingredients such as propane diol and/or formate and calcium
can be added to help stabilize the enzymes in well-known
fashion, according to the desires of the formulator.
Moreover, the compositions herein can contain, in
addition to ingredients already mentioned, various other
optional ingredients typically used in commercial products to
provide aesthetic- or additional product performance benefits.
Typical ingredients include pH regulants, perfumes, dyes,
optical brighteners, soil suspending agents, hydrotopes and
gel-control agents, freeze-thaw stabilizers, bactericides,
preservatives, suds control agents and the like. Such
ingredients typically comprise 0.1% - 10% of the
formulations.
Water or water-alcohol (e.g., ethanol, isopropanol,
etc.) mixtures are used as the carrier vehicle, and alkylated
polysaccharides can be used to increase the stability and
performanc~ characteristics of the compositions.
~ 230534
Inustrial App'ication
.:-e Lo~ lowina e.~ampLes describe a variety of formulations
;;..lC'' can be ~re~ared in the manner of the present invention.
~e examDles are a;iven by wav of illustration and are not
ntande~ ~o be li,T,iting of the scope of the invention. In
.he polvamine-containing formulations listed, the terms "x"
and "y" are stated in parentheses to designate the degree of
polymerization and degree of alkoxylation of the polyamine.
For some "polyamines", the designation R is also included,
therebv denoting a quaternarized polyamine. For such auater-
narized materials, the resulting anion X is of no consequence
to cleaning performance, and is not designated.
..~e~y-n~y.li~i~ e~
Special attention is directed to highly preferred
formula-tions which are particularly useful as heavy duty
liquid detergents that are suitable for laundering all
manner of fabrics in a typical home laundering operation.
The heavy duty liquid detergents disclosed hereinafter are
formulated with a variety of detersive ingredients to provide
excellent cleaning of a wide variety soils and stains, with
particularly noteworthy benefits with regard to cosmetic and
dirty motor oil stains.
It is to be understood that the following formulations
are in the fonn of oil-in-water emulsions (wherein the sol-
vent is considered the "oil" phase) and are substantially
clear, homogeneous, stable microemulsions. Surprisingly,
when used in a pre-treatment mode, the oil-in-water micro-
emulsions herein are comparable in grease-cutting performance
to water-in-oil emulsions, which have much higher concentra-
tions of solvent. The compositions also exhibit excellent
whiteness maintenance on cotton fabrics, apparently because
the solvent reduces fatty acid soap build-up on fabric
surfaces and the pH of the composition enhances enzyme
cleaning performance. These performance advanta~es are
particularly noti~ceable after multi-cycle washings.
~Z30534
The preparation of s-table, heavy-duty liq~id detergents
in their preferred oil-in-water microemulsion ~orm iS
carried-out with attention being ~iven to the water carrier
liquid, the use of Eatty acid/soap as a detergency builder/
emulslon stabll~zer ingredient and proper attention to
pH regulation.
Fatty Acids and Soaps - Fatty acids ~uch as lauric,
myristic, palmitic, stearic and oleic acids, and poly-unsat-
urated fatty acids, as well as their water-soluble salts (i.e.,
"soaps") are employed in tlie present compositions to provide
clear, homogeneous ~ormula-tions containing the solvent and
water. Mixtures o fatty acids (or soaps) such as palm
oil acids, coconut oil acids, and the lxke, in the Cl2-Cl8
carbon ~ai~ l~n~t~, can be used. ~'In general, the
concentration of fatty acid (or soap~ is from 5 % to 50 ~,
preferably 5 ~ to 35 ~, most preferably ln % to ~0 ~, and the
weight ratio of fatty acid (or soap):solvent is generally in
the range of 4:l to l:4, preferably 3:l to l:2. When using
fatty soap, the potassium salt and sodium forms are preferred,
but any convenient water-soluble salt may be used.
Apart from their function as microemulsion stabilizers,
these fatty acid/soap materials provide an important deter-
gency bui~lder function in the present compositions. However,
it has now been discovered that when formulating oil-in-
water microemulsion compositions at a pH greater than about
6.5, the presence of fatty acid/soap can actually destabilize
the system. Means or overcQming this de-stabilization while
maintaining a pH of 6,5 or aboYe in microemulsions containing
builder levels of fatty acid/soap are disclosed in detail,
here~nafte~.
Water - The liquid compositions herein may properly be
characterized ~s "water-based", in contXast wi~th or~nic solvent-
based cleaners known in ~he art.
/~
lZ~053A
SurprLsingly, water can inteLfere with the ability of
solven~s to remove gre~sy stains from fabrics, For example,
a fabric stai~ned w~th motor oil and dampened with ~,a,ter
prior to tre~tment with a terpene solvent is not very well
de-greased, if at all, By contrast, the present co~positions
whereIn the solvents are microemulsi~ied in water are
excellent greasy stain removers when used directly on dry or
damp fabrics.
Apart ~rom water's obvious envi~ronmental ~nd safety
pedigrees and lo~ cost as opposed to organic solvents,
water-based heavy duty liquid detergents offer ease-of-for-
mulation ad~antages with respect to Ingredients such as most
detergency bui~lders, sani~tizers, chelants, soil-suspending
agents, pH-control agents, and the l~ke, which are usually
water-soluble.
Accordingly, the compositions hereIn exhibit the
advantages of water-based for~ulation flexibility, together
with the superior grease removal qualities of solvent-based
compositions.
As will be described more fully hereinafter, the
present compositions generally comprise from 10 % to 70 %,
preferably 20 '~ to 50 ~ water. The weight ratio of
water:solvent is generally 10:1 to 1:1, preferably 5:1 to
2:1.
pH/S*abilizer - As is well-known in the detergency arts,
it is preferred for detergent compositions to be used in the
near-neutral to alkaline pH range, i.e., pH 6.5, and above.
This is for a variety of reasons. For example, many soils
are partly peptized or emulsified by alkalinity, itself. And,
many commercially aYailable detersive enzymes (e,g,, the
"alkaline protea,ses") function optimally in alkaline
laundering liquors~
It has nDw been d~scovere,d tha,t stable ol~-in-water
microemuls~on detergent compos,itions, ~hich co~pr~se builder
leveis of fatty acid/s~a~p are. de-st,a,bilized ~hen the~r ",as-is" pH
/~
OS;~A
lS ad~usted to about 6.5, and above. (The pH where instabi-
lity is noted may vary slightly with the actual grease-cutting
sol~en~ ~IsQ~l in the mi.cruelllulsio~, i-ts lev~l, and the chain length and de-gree of unsaturation of the fatty acid.) This prob]em is
especially acute with substantially non-polar, hydrocarbon
grease-cutting solvents, e.g., alkyl benzenes and alpha-oleflns~
and liquid paraffin solvents.
The stability problem seems to arise by virtue of the
fatty acid, which has an HLB of approximately 2, being con-
verted almost entirely to soap, with an HLB of about 20,
over a very narrow pH range, roughly 6.5-6.9. Thus, since
the fatty acid is present in substantial amounts (ca. 5~,
and higher) this major shift in HLB upsets the HLB of the
emulsification system and results in de-stabilization.
It is to be understood that formulation stability
could theoretically be achieved ~y proper selection of
surfactants (discussed hereinafter) with low HLB's. For
example, nonionic surfactants such as Cl4 15 alcohols with
low ethoxylate numbers (1-3) could be used. However, such
low HLB surfactants do not function well as detersive sur-
factants, and the object herein is not only to provide
stable mlcr~emulsions, but also good pre-treat and through-
the-wash detergency.
It has now been found that by either increasing the
ionic strength of the aqueous phase, or by adding solvent-
soluble ingredients with low HLB's, which increase solvent polarity, to the
solvent phase, or by us~ both means conjointly, the microemulsion is stabilizec.In particular, adding water-soluble, high ionic strength
ingredients such as, for example, formate, sulfate, citrate,
and the like, increases stability. By contrast, adding
water-soluble, low ionic strength materials such as
ethanol has no stabilizing effect.
)534
Also, adding slightly polar but solvent-soluble
ingredients with low HLB's such as n-hexanol, benzyl alcohol,
diethyl phthalate and the like increases stability.
Conjointly adding the ionic strength ingredients and
the solvent-soluble ingredients further enchances stability.
Of course, the formulator can select ingredients with a
view towards not only increasing microemulsion stability, but
also providing optimal cleaning benefits. For example, one
can choose citrate as an ionic strength agent which also
has detergency builder properties, formate as an ionic
strength agent which also stabilizes detergent enzymes, and
n-hexanol or benzyl alcohol or diethyl phthalate as a low
HLB ingredient which also serves a useful co-solvent
cleaning function.
The amount of ionic strength or low e.g. (2-5) HLB
solvent-soluble ingredients, or both, used in the
compositions will depend somewhat on the pH desired, the
concentration of fatty acid, the level of grease-cutting
solvent, the composition of the detersive surfactant system,
and the like. Microemulsion stability can be monitored
rather simply since the true microemulsions are clear, but
turn hazy and non-homogeneous,with eventual phase
separation at the point of instability. Moreover, true
oil-in-water microemulsions turn hazy when diluted with
water, whereas water-in-oil emulsions tend to gel, and
micellar oil-plus-water systems remain clear.
With regard to pH adjustments in the comPositions u~ to a~out
pY.6.5-6.6, any of the well-known base materials can be used, for example,
triethanolamine, alkali metal hydroxide and the like.
Potassium hydroxide is preferred over sodium hydroxide,
inasmuch as the ease of formulation of stable systems is
increased substantially by the potassium cation.
Nitrogen-functional Stabllizers/pH Regulants - It has
now been discovered that various alkyl and cyclo-alkyl amines,
quaternary ammonium compounds and amine oxides constitute
a highly preferred class of pH regulants and stabilizers in
the oil-in-water microemulsion detergent compositions of the
~230~i3~
present type. Apparently, such materials may somehow
associate with the fatty acid or anionic surfactants to
form a complex which stabilizes the microemulsified oil
(solvent). While the nitrogen functional compounds do not
boost the pH very much towards the alkaline range (only
several tenths of a pH unit, measured on the product formul-
ated "as is") the resulting boost in detergency performance
is substantial.
Dioctyl dimethyl ammonium chloride is a highly
preferred quaternary used herein as a pH-regulant, but
there can also be mentioned the following quaternaries
in increasing order of preference of use : coconut trimethyl
ammonium chloride (6.66) ; di-coconut dimethyl ammonium
chloride (6.84) ; coconut benzyl dimethyl ammonium chloride
(6.84) ; and dihexyl dimethyl ammonium chloride (6.89). The
numbers in parentheses denote the pH achievable by adding
the respective quaternaries to a liquid oil-in-water
microemulsion containing fatty acid and formulated at an
"as is" pH of 6.5. For the preferred dioctyl dimethyl
ammonium chloride, the pH figure is 6.94.
Suitable alkyl and cyclo-alkyl amines-useful herein
(with attendant pH's) include : coconutalkyl diethanol
amine (6.65) ; coconutalkyl dimethyl amine (6.75) ;
trioctyl amine (7.0) ; and cyclohexyl amine (7.5).
Suitable amine oxides herein include coconutalkyl
dimethylamine oxide (6.7) and dioctyl methylamine oxide
(est.> 7).
It is to be understood that the foregoing nitrogen
compounds are added to the compositions until the desired
pH is obtained. To achieve the pH listed,from 0.5~ to 5~ -
of the compounds are typically used in the compositions. Cyclo-
hexyl amine (1-5~) is most preferred for use herein.
The highly preferred, fully-formulated compositons
herein are in liquid form, which can be prepared by simply
blending the essential and optional ingredients in the
aqueous carrier. Microemulsion stability can be estimated
visually by watching for phase separation, or can be
monitored more quantitatively by standard turbidometric
/~
/~
1230534
techniques.
In one process aspect, the compositions can be used
to pre-treat soiled fabrics by rubbing a few milliliters
of the composition directly onto and into the soiled
5 area, followed by laundering, in standard fashion. In a
through-the-wash mode, the compositions are typically used
at a concentration of at least 500 ppm, preferably O.l % to
l.5 % in an aqueous laundry bath at p~ 6.5 and above to
launder fabrics. The laundering can be carried out over
the range from 5 C to the boil, with excellent results.
For use on hard surfaces, as rug cleaners, and as
general-purpose cleaners, such compositions are usually
diluted with water.
The following ~xamples illustrate the practice of
this invention, but are not intended to be limiting
thereof.
/?
lZ30534
EXAMPLE I
INGREDIENT % By Weight
Cll 8 Alkyl Benzene Sulphonic Acid 10.0
14/15 Alkyl Ethoxylate (E0 7) 10.9
Coconut Fatty Acid (Broad Cut) 18.2
Oleic Acid 2.3
Monomethyl Ethanolamine 5.8
n-Octyl Benzene 9.1
Ethanol (95 %) 2.7
DEQUEST (50 %)1 1.09
Formic Acid 0.18
K3 Citrate.H2O (63.5% in H2O) 4-4
CaC12.2H20 0.05
Maxatase Enzyme (Protease) 0.73
Termamyl Enzyme (amylase) 0.10
Ethoxylated Polyamine 2. 1.73
Perfume/Optical Brightener/Dye 0.5
Water Balance
Product pH "as is" 6.6
Dioctyl Dimethyl Ammonium Chloride to pH 6.94
1. Diethylene triamine pentamethylenephosphonic
acid.
2, Tetraethylene Pentamine 105 EO units/molecule
The composition of Example I is a stable, oil-in-water
microemulsion suitable for use as a laundry detergent.
~230~;34
EX~MPLE II
-
The composition of Example I is modified by replacing the
n-octyl benzene by the same amount (9.1 % total formulation) of
l-decene. Product pH "as is" : 6.6. The pH is adjusted to
6.94 with dioctyl dimethyl ammonium chloride.
EXAMPLE III
The composition of Example I is modified by replacing the
n-octyl benzene by any of the following solvent mixtures
(percentages of total formulation being specified in parentheses):
l-Decene (6.1 %) Diethylphthalate (3.0 %); l-Dodecene (7.3 %)/
Benzyl alcohol (1.8 %) ; n-octyl benzene (6.2 %)/Diethylphthalate
(2.9 %) ; octyl benzene (6.0 %)/Butyl Carbitol (3.1 %).
Product pH's as is : 6.6 In each instance, product pH is
adjusted to 6.9 with dioctyl dimethyl ammonium chloride.
EXAMPLE IV
The compositions of Example III comprising solvent
mixtures are adjusted to pH 7.0 with trioctyl amine and to
pH 7.1 with dioctyl methylamine oxide, respectively, and
stable, microemulsions are secured.
As can be seen from the foregoing, the present invention
provides effective means whereby microemulsions comprising
fatty acid~soap at high levels can be adjusted to a preferred
pH range of 6.65 to 7.3 using mono- and di- C6-C18 tri- and
dimethyl ammonium salts ; or C4-C8 alkyl or cycloalkyl amines;
or mono- and di- C6C18 alkyl dimethyl and monomethyl amine
oxides.
Further examples of the compositions herein are as
follows.
EXAMPLE V
The composition of Example I is modified by replacing
the Ethoxylated Polyamine with any of the following
alkoxylated polyamines A, ~ or C, having the general formula
disclosed hereinbefore.
Iq
lZ30S34
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Polyamine A : x = 2; y = 2; R = ethylene; aIkoxy = ethoxy
Polyamine B : x = 20; y = 30; R = propylene;alkoxy = propoxy
Polyamine C : x = 3, y = 15; R = ethylene; alkoxy = ethoxy; R' = butyl
The alkoxylated polyamines contribute to the clay
soil removal performance of the compositions.
EXAMPLE VI
The pH of the compositions of Example V are adjusted to
7.3 with addition of 5 parts (by weight of composition)
of cyclohexyl amine.
EXAMPLE VII
The composition of example II is modified by replacing
the l-Decene by a mix of 6 % diethylphthalate/2 % liquid
iso-paraffin/2 % orange terpene . The product is
stable at pH 6.94 when dioctyl dimethyl ammonium chloride
is present at a level of about 2.5 %.
Another preferred olefin solvent herein by virtue of
its relatively low odor is the so-called "P-4" polymer,
available from a number of petrochemical suppliers to
the detergent industry as a raw material for branched
alkyl benzene. P-4 is an isomer mix of the condensation
product of 4 moles of propylene, i.e., Cl2 branched olefins.
P-4 is non-polar, and is preferably used in combination with
a polar solvent such as benzyl alcohol, diethylphthate, Butyl
Carbitol or the like,
Other useful polar solvents herein include the "Cellosolves"
e.g. alkoxyl alkanols such as 2-butoxyethanol ; C6-C12 alkanols
lincluding benzyl alcohol) such as dodecanol, phenethyl alcohol,
diglycolether acetates, and the like.
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EXAMPLE VI I I
Other solvent mixtures useLul herein are as follows.
Composition Inqredient Percent
A Octyl benzene 70%
Diethyl phthalate 30%
B '-Decene 70%
Diethyl phthalate 30%
C Octyl benzene 80%
Benzyl alcohol 20%
D n-Octyl benzene 90%
Butyl carbitol 10%
E l-Decene 65%
Dibutyl phthalate 35%
F n-Octyl benzene 30%
l-Decene 40%
Benzyl alcohol 10%
Butyl carbitol 20%
G l-Decene 80%
n-Hexanol 20%
H l-Decene 60%
Diethyl phthalate 40%
I l-Dodecene 80%
Hexyl cellosolve 20%
J Mixed 1:1 nonyl/hexyl benzene 35%
2-Dodecene 35%
Dimethyl phthalate 30%
In a preferred method of use aspect, the compositions
herein are used in an aqueous laundering liquor,
preferably at a liquor pH of 6.5-8.0 tmeasured as 1% of
composition in water) to launder fabrics. Excellent
cleaning is attained by agitating fabrics in such liquors
especially at this preferred in-use pH range.
1230534
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E_MPLE IX
A highly preferred liquid laundry detergent by virtue
of the low odor properties o~ its grease removal solvent
system, its stability in microemulsion form, and its
enzymatic cleaning activity (by virtue of its pH) is as
follows.
Inqredient Parts by Weiqht
Alkyl(Cll 8)benzene sulfonic acid 11.0
Alkyl(cl4/l5)ethoxylate (E07) 12.0
Topped whole cut coconut fatty acid (1) 20.5
C10~ soparaffins 4 0
Diethyl phthalate 6.0
Cyclohexylamine 2.0
Monomethyl ethanolamine (2)4.3
Pota~sium citrate monohydrate
(63.5% in water) 2.4
Dequest 2060 S 1.7
Ethoxylated polyamine (x=5, y=15) 1.5
Ethanol 3.0
Potassium hydroxide (50% in water) (2) 3.0
Formic acid 0.2
CaC12 2H2O 0.05
Optical brightener (anionic) 0.18
Maxatase enzyme (3) 0.71
Termamyl 300L enzyme (4) 0.10
Dye 20 ppm
Perfume 0 5
Water up to 110 parts
Product pH 6.9
(1) Chain length mixture: Clo(5%) Clz(55%) C~(22~)
C18(2~) oleic(lo%)
(2) To adjust pH to 6.6
(3) From KNGS
(4) From NOVO
~30534
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The composition of Example IX is used in an aqueous
laundry bath at a concentration of 100ml/10 liters and
provides an in-use pH of about 7.2 (varies with water
hardness).
As can be seen from the foregoing, the primary amines
are preferred pH-adjusting agents herein. In general, the
C4-C18 alkyl amines are used, since the lower
molecular weight amines tend to be excessively
malodorous. Other examples of amines useful herein
include dibutyl- and di-isobutyl amine. For typical use
in detergent compositions intended for home-use, amines
having a boiling point above 100C are preferred.
Product "as is" pH is measured at ambient (23C)
temperature using a commercial pH meter. The electrode is
immersed in the product and the meter is allowed to
stabilize before reading.
