Field of the Invention
[0001] This invention relates to an improved all-purpose liquid cleaner in the form of a
microemulsion designed in particular for cleaning hard surfaces and which is effective
in removing grease soil and/or bath soil and in leaving unrinsed surfaces with a shiny
appearance.
Background of the Invention
[0002] In recent years all-purpose liquid detergents have become widely accepted for cleaning
hard surfaces, e.g., painted woodwork and panels, tiled walls, wash bowls, bathtubs,
linoleum or tile floors, washable wall paper, etc.. Such all-purpose liquids comprise
clear and opaque aqueous mixtures of water-soluble synthetic organic detergents and
water-soluble detergent builder salts. In order to achieve comparable cleaning efficiency
with granular or powdered all-purpose cleaning compositions, use of water-soluble
inorganic phosphate builder salts was favored in the prior art all-purpose liquids.
For example, such early phosphate-containing compositions are described in U.S. Patent
Nos. 2,560,839; 3,234,138; 3,350,319; and British Patent No. 1,223,739.
[0003] In view of the environmentalist's efforts to reduce phosphate levels in ground water,
improved all-purpose liquids containing reduced concentrations of inorganic phosphate
builder salts or non-phosphate builder salts have appeared. A particularly useful
self-opacified liquid of the latter type is described in U.S. Patent No. 4,244,840.
[0004] However, these prior art all-purpose liquid detergents containing detergent builder
salts or other equivalent tend to leave films, spots or streaks on cleaned unrinsed
surfaces, particularly shiny surfaces. Thus, such liquids require thorough rinsing
of the cleaned surfaces which is a time-consuming chore for the user.
[0005] In order to overcome the foregoing disadvantage of the prior art all-purpose liquid,
U.S. Patent No. 4,017,409 teaches that a mixture of paraffin sulfonate and a reduced
concentration of inorganic phosphate builder salt should be employed. However, such
compositions are not completely acceptable from an environmental point of view based
upon the phosphate content. On the other hand, another alternative to achieving phosphate-free
all-purpose liquids has been to use a major proportion of a mixture of anionic and
nonionic detergents with minor amounts of glycol ether solvent and organic amine as
shown in U.S. Patent NO. 3,935,130. Again, this approach has not been completely satisfactory
and the high levels of organic detergents necessary to achieve cleaning cause foaming
which, in turn, leads to the need for thorough rinsing which has been found to be
undesirable to today's consumers.
[0006] Another approach to formulating hard surface or all-purpose liquid detergent composition
where product homogeneity and clarity are important considerations involves the formation
of oil-in-water (o/w) microemulsions which contain one or more surface-active detergent
compounds, a water-immiscible solvent (typically a hydrocarbon solvent), water and
a "cosurfactant" compound which provides product stability. By definition, an o/w
microemulsion is a spontaneously forming colloidal dispersion of "oil" phase particles
having a particle size in the range of 25 Å to 800 Å in a continuous aqueous phase.
[0007] In view of the extremely fine particle size of the dispersed oil phase particles,
microemulsions are transparent to light and are clear and usually highly stable against
phase separation.
[0008] Patent disclosures relating to use of grease-removal solvents in o/w microemulsions
include, for example, European Patent Applications EP 0137615 and EP 0137616 - Herbots
et al; European Patent Application EP 0160762 - Johnston et al; and U.S. Patent No.
4,561,991- Herbots et al. Each of these patent disclosures also teaches using at least
5% by weight of grease-removal solvent.
[0009] It also is known from British Patent Application GB 2144763A to Herbots et al, published
March 13, 1985, that magnesium salts enhance grease-removal performance of organic
grease-removal solvents, such as the terpenes, in o/w microemulsion liquid detergent
compositions. The compositions of this invention described by Herbots et al. require
at least 5% of the mixture of grease-removal solvent and magnesium salt and preferably
at least 5% of solvent (which may be a mixture of water-immiscible non-polar solvent
with a sparingly soluble slightly polar solvent) and at least 0.1% magnesium salt.
[0010] However, since the amount of water immiscible and sparingly soluble components which
can be present in an o/w microemulsion, with low total active ingredients without
impairing the stability of the microemulsion is rather limited (for example, up to
18% by weight of the aqueous phase), the presence of such high quantities of grease-removal
solvent tend to reduce the total amount of greasy or oily soils which can be taken
up by and into the microemulsion without causing phase separation.
[0011] The following representative prior art patents also relate to liquid detergent cleaning
compositions in the form of o/w microemulsions: U.S. Patents Nos.. 4,472,291 - Rosario;
4,540,448 - Gauteer et al; 3,723,330 - Sheflin; etc.
[0012] Liquid detergent compositions which include terpenes, such as d-limonene, or other
grease-removal solvent, although not disclosed to be in the form of o/w microemulsions,
are the subject matter of the following representative patent documents: European
Patent Application 0080749; British Patent Specification 1,603,047; US 4,414,128;
and US 4,540,505. For example, U.S. Patent No. 4,414,128 broadly discloses an aqueous
liquid detergent composition characterized by, by weight:
(a) from 1% to 20% of a synthetic anionic, nonionic, amphoteric or zwitterionic surfactant
or mixture thereof;
(b) from 0.5% to 10% of a mono- or sesquiterpene or mixture thereof, at a weight ratio
of (a):(b) lying in the range of 5:1 to 1:3; and
(c ) from 0.5% 10% of a polar solvent having a solubility in water at 15°C in the
range of from 0.2% to 10%. Other ingredients present in the formulations disclosed
in this patent include from 0.05% to 2% by weight of an alkali metal, ammonium or
alkanolammonium soap of a C13-C24 fatty acid; a calcium sequestrant from 0.5% to 13% by weight; non-aqueous solvent,
e.g., alcohols and glycol ethers, up to 10% by weight; and hydrotropes, e.g., urea,
ethanolamines, salts of lower alkylaryl sulfonates, up to 10% by weight. All of the
formulations shown in the Examples of this patent include relatively large amounts
of detergent builder salts which are detrimental to surface shine.
[0013] Furthermore, the present inventors have observed that in formulations containing
grease-removal assisting magnesium compounds, the addition of minor amounts of builder
salts, such as alkali metal polyphosphates, alkali metal carbonates, nitrilotriacetic
acid salts, and so on, tends to make it more difficult to form stable microemulsion
systems.
[0014] U.S. Patent 5,082,584 discloses a microemulsion composition having an anionic surfactant,
a cosurfactant, nonionic surfactant, perfume and water; however, these compositions
do not possess the low ecotoxicity profile and the improved interfacial tension properties
as exhibited by the compositions of the instant invention.
[0015] British Patent No 1,453,385 discloses polyesterified nonionic surfactants similar
to the polyesterified nonionic surfactants of the instant invention. However, these
nonionic surfactants of British Patent 1,453,385 do not disclose the formula (II)
portion of the instant composition. Additionally, the formulated compositions of British
Patent 1,453,385 fail to disclose the critical limitations of the instant invention.
[0016] A number of patents teach esterified ethoxylated glycerol compounds for various applications.
These patents are Great Britian 1,453,385; Japan 59-1600 and Japan 58-206693 and European
Patent Application 0586,323A1. These publications fail to appreciate that a mixture
of esterified ethoxylated glycerol and nonesterified ethoxylated glycerol, when used
in a hard surface cleaning composition, functions as a grease release agent.
Summary of the Invention
[0017] The present invention provides an improved, clear, liquid cleaning composition having
improved interfacial tension which improves cleaning hard surface in the form of a
microemulsion which is suitable for cleaning hard surfaces such as plastic, vitreous
and metal surfaces having a shiny finish.
[0018] According to the present invention there is provided a microemulsion composition
having a viscosity at 25°C of 6 to 60 mPa·s, comprising water and by weight:
(a) 0.1% to 20% of a mixture of
and
wherein w equals one to four, B is selected from the group consisting of hydrogen
or a group represented by -CO-R, wherein R is selected from the group consisting of
alkyl group having 6 to 22 carbon atoms, and alkenyl groups having 6 to 22 carbon
atoms, wherein at least one of the B groups is represented by said -CO-R, R' is selected
from the group consisting of hydrogen and methyl groups; x, y and z have a value between
0 and 60, provided that (x+y+z) equals 2 to 100, wherein in Formula (I) the ratio
of monoester / diester / triester is 45 to 90 / 5 to 40 / 1 to 20, wherein the ratio
of Formula (I) to Formula (II) is a value between 3 to 0.02;
(b) 0.1% to 20% of an anionic surfactant;
(c) 0.1% to 50% of a cosurfactant;
(d) 0.1% to 10% of a water insoluble hydrocarbon or a perfume;
(e) 0.4% to 1.0% of a tri-alkyl citrate and
(f) the balance being water, said composition not containing a zwitterionic surfactant,
methanol, ethanol, alkali metal silicates, alkali metal polyphosphates, alkali metal
carbonates, alkali metal phosphonates or alkali metal citrates.
[0019] According to the present invention there is also provided a stable concentrated microemulsion
composition having a viscosity at 25°C of 6 to 60 mPa·s, comprising water and by weight:
(a) 1% to 30% of an anionic surfactant;
(b) 0.5% to 15% of a mixture of a compound of Formula (I) and a compound of Formula
(II), wherein w, B, R, R', y and z are as defined above, (x+y+z) equals 2 to 100,
wherein in Formula (I) the ratio of monoester / diester / triester is 45 to 90 / 5
to 40 / 1 to 20, wherein the ratio of Formula (I) to Formula (II) is a value between
3 to 0.02,
(c) 2% to 30% of a cosurfactant;
(d) 0.4% to 10% of a water insoluble hydrocarbon or a perfume;
(e) 0 to 18% of at least one dicarboxylic acid;
(f) 0 to 0.2% of an aminoalkylene phosphonic acid;
(g) 0 to 1.0% of phosphoric acid;
(h) 0 to 15% of magnesium sulfate heptahydrate;
(i) 0.4% to 1.0% of a tri-alkyl citrate; and
(h) the balance being water, wherein the composition has an ecotoxicity value as measured
by the LC50 test of at least 0.18 ml/L measured on Daphniae microorganisms and said
composition does not contain methanol, a zwitterionic surfactant, ethanol, alkali
metal silicates, alkali metal polyphosphates, alkali metal carbonates, alkali metal
phosphonates or alkali metal citrates.
[0020] More particularly, the improved cleaning compositions exhibit good grease soil removal
properties due to the improved interfacial tensions, when used in undiluted (neat)
form and leave the cleaned surfaces shiny without the need of or requiring only minimal
additional rinsing or wiping. The latter characteristic is evidenced by little or
no visible residues on the unrinsed cleaned surfaces and, accordingly, overcomes one
of the disadvantages of prior art products. The instant compositions exhibit a grease
release effect in that the instant compositions impede or decrease the anchoring of
greasy soil on surfaces that have been cleaned with the instant compositions as compared
to surfaces cleaned with a liquid crystal composition or a commercial microemulsion
composition which means that the grease soiled surface is easier to clean upon subsequent
cleanings. Surprisingly, these desirable results are accomplished even in the absence
of polyphosphate or other inorganic or organic detergent builder salts and also in
the complete absence or substantially complete absence of grease-removal solvent.
[0021] The instant compositions are more friendly for the environment due to the low ecotoxicity
of the ethoxylated glycerol type compounds used in the instant compositions.
[0022] The compositions of the instant invention have an ecotoxocity value as measured by
the LC 50 test as deferred by The Organization for Economic Cooperation and Development
(OECD)(of which the United States is a member) in OECD Test No. 202 of at least 0.18
ml/L measured on Daphniae microorganisms.
[0023] In one aspect, the invention generally provides a stable, clear all-purpose, hard
surface cleaning composition especially effective in the removal of oily and greasy
oil, which is in the form of a substantially dilute oil-in-water microemulsion having
an aqueous phase and an oil phase. The dilute o/w microemulsion comprises on a weight
basis:
from 0.1% to 20% of an anionic surfactant;
from 0.1% to 50% of a water-mixable cosurfactant having either limited ability or
substantially no ability to dissolve oily or greasy soil;
0.1% to 20% of a compound which is a mixture of a partially esterified ethoxylated
polyhydric alcohol, a fully esterified ethoxylated polyhydric alcohol and a nonesterified
ethoxylated polyhydric alcohol (herein after referred to as an ethoxylated glycerol
type compound);
0 to 15% of magnesium sulfate heptahydrate;
0.1 to 10.0% of a perfume or water insoluble hydrocarbon;
0.4 to 1.0 % of a tri-alkyl citrate; and
10 to 85% of water, said proportions being based upon the total weight of the composition.
[0024] In another aspect, the invention generally provides a stable, clear all-purpose,
hard surface cleaning composition especially effective in the removal of oily and
greasy oil, which is in the form of a substantially dilute oil-in-water microemulsion
having an aqueous phase and an oil phase. The aqueous phase of the dilute o/w microemulsion
comprises on a weight basis:
from 0.1% to 20% of an anionic surfactant;
from 0.1% to 50% of a water-mixable cosurfactant having either limited ability or
substantially no ability to dissolve oily or greasy soil;
0.4% to 1.0% of a trialkyl ester of citric acid;
0.1% to 10% of a mixture of a partially esterified ethoxylated polyhydric alcohol,
a fully esterified ethoxylated polyhydric alcohol and a nonesterified polyhydric alcohol,
(said mixture being herein after referred to as an ethoxylated glycerol type compound);
0 to 15% of magnesium sulfate heptahydrate;
0.4 to 10.0% of a perfume or water insoluble hydrocarbon; and
10 to 85% of water, said proportions being based upon the total weight of the composition.
[0025] In another aspect, the invention generally provides a stable, clear all-purpose,
hard surface cleaning composition especially effective in the removal of particle
soil, which is in the form of a substantially dilute oil-in-water microemulsion having
an aqueous phase and an oil phase. The dilute o/w microemulsion comprises on a weight
basis:
from 0.1 % to 20% of an anionic surfactant;
from 0.1% to 50% of a water-mixable cosurfactant having either limited ability or
substantially no ability to dissolve oily or greasy soil;
0.1% to 20% of an ethoxylated polyhydric alcohol;
0 to 15% of magnesium sulfate heptahydrate;
0.1 to 10.0% of a perfume or water insoluble hydrocarbon;
0.4 to 1.0% of a tri-alkyl citrate; and
10 to 85% of water, said proportions being based upon the total weight of the composition.
This composition can also contain 0 to 10 wt. % of a monoester of an ethoxylated polyhydric
alcohol depicted by the formula:
wherein w equals one to four. Two of the B's are hydrogen and one B is selected from
the group consisting of a group represented by:
wherein R is selected from the group consisting of alkyl group having 6 to 22 carbon
atoms, more preferably 11 to 15 carbon atoms and alkenyl groups having 6 to 22 carbon
atoms, wherein a hydrogenated tallow alkyl chain or a coco alkyl chain is most preferred,
x, y and z have a value between 0 and 60, provided that (x+y+z) equals about 2 to
about 100. This composition can also contain 0 to 2 wt. %, of a diester of an ethoxylated
polyhydric alcohol depicted by the formula
wherein w equals one to four. One of the B's is hydrogen and two B's are selected
from the group consisting of a group represented by:
wherein R is selected from the group consisting of alkyl group having 6 to 22 carbon
atoms, and alkenyl groups having 6 to 22 carbon atoms, wherein a hydrogenated tallow
alkyl chain or a coco alkyl chain is most preferred, x, y and z have a value between
0 and 60, provided that (x+y+z) equals 2 to 100. This composition can also contain
0 to 1.0 wt. %, of a triester of an ethoxylated polyhydric alcohol depicted by the
formula
wherein w equals one to four. The three B's are selected from the group consisting
of a group represented by:
wherein R is selected from the group consisting of alkyl group having 6 to 22 carbon
atoms, and alkenyl groups having 6 to 22 carbon atoms, wherein a hydrogenated tallow
alkyl chain or a coco alkyl chain is most preferred, x, y and z have a value between
0 and 60, provided that (x+y+z) equals about 2 to about 100.
[0026] The dispersed oil phase of the o/w microemulsion is composed essentially of the water-immiscible
or hardly water-soluble perfume.
[0027] Quite surprisingly although the perfume is not, per se, a solvent for greasy or oily
soil, -- even though some perfumes may, in fact, contain as much as 80% of terpenes
which are known as good grease solvents -- the inventive compositions in dilute form
have the capacity to solubilize up to 10 times or more of the weight of the perfume
of oily and greasy soil, which is removed or loosened from the hard surface by virtue
of the action of the anionic and nonionic surfactants, said soil being taken up into
the oil phase of the o/w microemulsion.
[0028] In another aspect, the invention generally provides highly concentrated microemulsion
compositions in the form of either an oil-in-water (o/w) microemulsion or a water-in-oil
(w/o) microemulsion which when diluted with additional water before use can form dilute
o/w microemulsion compositions. The concentrated microemulsion compositions comprise,
by weight, 0.1% to 20% of an anionic surfactant, 0.1% to 20% of an ethoxylated glycerol
type compound, 0% to 2.5% of a fatty acid, 0.1% to 10% of perfume or water insoluble
hydrocarbon having 6 to 18 carbon atoms, 0.1% to 50% of a cosurfactant, 0.4 to 1.0
% of a tri-alkyl citrate, and 20% to 97% of water.
[0029] In another aspect, the invention provides highly concentration microemulsion compositions
in the form of either an oil-in-water (o/w) microemulsion or a water-in-oil (w/o)
microemulsion which when diluted with additional water before use can form dilute
o/w microemulsion compositions. The concentrated microemulsion compositions comprise,
by weight, 0.1 % to 20% of an anionic surfactant, 0.1% to 20% of an ethoxylated glycerol
type compound, 0% to 2.5% of a fatty acid, 0.1% to 10% of perfume or water insoluble
hydrocarbon having 6 to 18 carbon atoms, 0.1% to 50% of a cosurfactant, 0.4 to 1.0
% of a tri-alkyl citrate, and 20% to 97% of water.
[0030] in another aspect, the invention generally provides highly concentrated microemulsion
compositions in the form of either an oil-in-water (o/w) microemulsion or a water-in-oil
(w/o) microemulsion which when diluted with additional water before use can form dilute
o/w microemulsion compositions. The concentrated microemulsion compositions comprise,
by weight, 0.1% to 20% of an anionic surfactant, 0.1% to 20% of an ethoxylated polyhydric
alcohol, 0.1% to 10% of perfume or water insoluble hydrocarbon having 6 to 18 carbon
atoms, 0.1% to 50% of a cosurfactant, 0.4 to 1.0 % of a tri-alkyl citrate and 20%
to 97% of water.
Detailed Description of the Invention
[0031] The present invention relates to a stable microemulsion composition comprising by
weight: 0.1% to 20% of an anionic surfactant, 0.1% to 50% of a cosurfactant, 0.1%
to 20% of an ethoxylated glycerol type compound, 0.1% to 10% of a water insoluble
hydrocarbon or a perfume, 0.4 to 1.0 of a tri-alkyl citrate and the balance being
water, said composition having an ecotoxocity value as measured by the LC50 test of
at least 0.18 ml/L measured on Daphniae microorganisms.
[0032] The present invention relates to a stable microemulsion composition comprising by
weight: 0.1% to 20% of an anionic surfactant, 0.1% to 50% of a cosurfactant, 0.4 to
1.0 wt. % of a trialkyl ester of citric acid such as tri-n butyl citrate, 0.1% to
20% of an ethoxylated glycerol type compound, 0.1% to 10% of a water insoluble hydrocarbon
or a perfume and the balance being water, said composition having an ecotoxocity value
as measured by the LC50 test of at least 0.18 ml/L measured on Daphniae microorganisms.
[0033] The present invention relates to a stable microemulsion composition comprising by
weight: 0.1% to 20% of an anionic surfactant, 0.1% to 50% of a cosurfactant, 0.1%
to 20% of an ethoxylated polyhydric alcohol, 0.1% to 10% of a water insoluble hydrocarbon
or a perfume, 0.4 to 1.0 % of a tri-alkyl citrate and the balance being water. This
composition can also contain 0 to 10 wt. % of a monoester of an ethoxylated polyhydric
alcohol depicted by the formula
wherein w equals one to four. Two of the B's are hydrogen and one B is selected from
the group consisting of a group represented by:
wherein R is selected from the group consisting of alkyl group having about 6 to
22 carbon atoms, and alkenyl groups having about 6 to 22 carbon atoms, wherein a hydrogenated
tallow alkyl chain or a coco alkyl chain is most preferred, x, y and z have a value
between 0 and 60, provided that (x+y+z) equals about 2 to about 100. This composition
can also contain 0 to 2 wt. % of a diester of an ethoxylated polyhydric alcohol depicted
by the formula
wherein w equals one to four. One of the B's is hydrogen and two B's are selected
from the group consisting of a group represented by:
wherein R is selected from the group consisting of alkyl group having about 6 to
22 carbon atoms, and alkenyl groups having about 6 to 22 carbon atoms, wherein a hydrogenated
tallow alkyl chain or a coco alkyl chain is most preferred, x, y and z have a value
between 0 and 60, provided that (x+y+z) equals about 2 to about 100. This composition
can also contain 0 to 1.0 wt. % of a triester of an ethoxylated polyhydric alcohol
depicted by the formula
wherein w equals one to four. The three B's are selected from the group consisting
of a group represented by:
wherein R is selected from the group consisting of alkyl group having 6 to 22 carbon
atoms, and alkenyl groups having 6 to 22 carbon atoms, wherein a hydrogenated tallow
alkyl chain or a coco alkyl chain is most preferred, x, y and z have a value between
0 and 60, provided that (x+y+z) equals 2 to 100.
[0034] According to the present invention, the role of the hydrocarbon is provided by a
non-water-soluble perfume. Typically, in aqueous based compositions the presence of
a solubilizers, such as alkali metal lower alkyl aryl sulfonate hydrotrope, triethanolamine,
urea, etc., is required for perfume dissolution, especially at perfume levels of 1%
and higher, since perfumes are generally a mixture of fragrant essential oils and
aromatic compounds which are generally not water-soluble. Therefore, by incorporating
the perfume into the aqueous cleaning composition as the oil (hydrocarbon) phase of
the ultimate o/w microemulsion composition, several different important advantages
are achieved.
[0035] First, the cosmetic properties of the ultimate cleaning composition are improved:
the compositions are both clear (as a consequence of the formation of a microemulsion)
and highly fragranced (as a consequence of the perfume level).
[0036] Second, the need for use of solubilizers, which do not contribute to cleaning performance,
is eliminated.
[0037] Third, an improved grease release effect and an improved grease removal capacity
in neat (undiluted) usage of the dilute aspect or after dilution of the concentrate
can be obtained without detergent builders or buffers or conventional grease removal
solvents at neutral or acidic pH and at low levels of active ingredients while improved
cleaning performance can also be achieved in diluted usage.
[0038] As used herein and in the appended claims the term "perfume" is used in its ordinary
sense to refer to and include any non-water soluble fragrant substance or mixture
of substances including natural (i.e., obtained by extraction of flower, herb, blossom
or plant), artificial (i.e., mixture of natural oils or oil constituents) and synthetically
produced substance) odoriferous substances. Typically, perfumes are complex mixtures
of blends of various organic compounds such as alcohols, aldehydes, ethers, aromatic
compounds and varying amounts of essential oils (e.g., terpenes) such as from 0% to
80%, by weight, the essential oils themselves being volatile odoriferous compounds
and also serving to dissolve the other components of the perfume.
[0039] In the present invention the precise composition of the perfume is of no particular
consequence to cleaning performance so long as it meets the criteria of water immiscibility
and having a pleasing odor. Naturally, of course, especially for cleaning compositions
intended for use in the home, the perfume, as well as all other ingredients, should
be cosmetically acceptable, i.e., non-toxic, hypoallergenic, etc.. The instant compositions
show a marked improvement in ecotoxocity as compared to existing commercial products.
[0040] The hydrocarbon such as a perfume is present in the dilute o/w microemulsion in an
amount of from 0.1% to 10% by weight. If the amount of hydrocarbon (perfume) is less
than 0.4% by weight it becomes more difficult to form the o/w microemulsion. In the
case of the liquid crystal one need at least 0.5 weight % of perfume. If the hydrocarbon
(perfume) is added in amounts more than 10% by weight, the cost is increased without
any additional cleaning benefit and, in fact, with some diminishing of cleaning performance
insofar as the total amount of greasy or oily soil which can be taken up in the oil
phase of the microemulsion will decrease proportionately.
[0041] Furthermore, although superior grease removal performance will be achieved for perfume
compositions not containing any terpene solvents, it is apparently difficult for perfumers
to formulate sufficiently inexpensive perfume compositions for products of this type
(i.e., very cost sensitive consumer-type products) which includes less than 20%, usually
less than 30%, of such terpene solvents.
[0042] Thus, merely as a practical matter, based on economic consideration, the dilute o/w
microemulsion detergent cleaning compositions of the present invention may often include
as much as 0.2% to 7% by weight, based on the total composition, of terpene solvents
introduced thereinto via the perfume component. However, even when the amount of terpene
solvent in the cleaning formulation is less than 1.5% by weight, such as up to 0.6%
by weight or 0.4% by weight or less, satisfactory grease removal and oil removal capacity
is provided by the inventive diluted o/w microemulsions.
[0043] Thus, for a typical formulation of a diluted o/w microemulsion according to this
invention a 20 milliliter sample of o/w microemulsion containing 1% by weight of perfume
will be able to solubilize, for example, up to 2 to 3 ml of greasy and/or oily soil,
while retaining its form as a microemulsion, regardless of whether the perfume contains
0%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7% or 0.8% by weight of terpene solvent.
In other words, it is an essential feature of the compositions of this invention that
grease removal is a function of the result of the microemulsion, per se, and not of
the presence or absence in the microemulsion of a "greasy soil removal" type of solvent.
[0044] In place of the perfume one can employ a water insoluble paraffin or isoparaffin
having 6 to 18 carbon at a concentration of 0.4 to 8.0 wt. percent.
[0045] The water-soluble organic detergent materials which are used in forming the ultimate
o/w microemulsion compositions of this invention may be selected from the group consisting
of water-soluble, non-soap, anionic surfactants mixed with a fatty acid and the solubilizing
agent which is a partially esterified ethoxylated polyhydric alcohol such as a partially
esterified ethoxylated glycerol.
[0046] Although conventional nonionic surfactants can be used in the instant compositions,
the employment of such conventional nonionic in the instant composition will decrease
the environmental profile of the composition as well as having an adverse effect on
the grease release and grease + particulate soil removal properties of the composition.
[0047] Regarding the anionic surfactant present in the o/w microemulsions any of the conventionally
used water-soluble anionic surfactants or mixtures of said anionic detergents and
anionic detergents can be used in this invention. As used herein the term "anionic
surfactant" is intended to refer to the class of anionic and mixed anionic-nonionic
surfactants providing detersive action.
[0048] Suitable water-soluble non-soap, anionic surfactants include those surface-active
or detergent compounds which contain an organic hydrophobic group containing generally
8 to 26 carbon atoms in their molecular structure and at least one water-solubilizing
group selected from the group of sulfonate, sulfate and carboxylate so as to form
a water-soluble surfactant. Usually, the hydrophobic group will include or comprise
a C
8-C
22 alkyl, alkyl or acyl group. Such surfactants are employed in the form of water-soluble
salts and the salt-forming cation usually is selected from the group consisting of
sodium, potassium, ammonium, magnesium and mono-, di- or tri-C
2-C
3 alkanolammonium, with the sodium, magnesium and ammonium cations again being preferred.
[0049] Examples of suitable sulfonated anionic surfactants are the well known higher alkyl
mononuclear aromatic sulfonates such as the higher alkyl benzene sulfonates containing
from 10 to 16 carbon atoms in the higher alkyl group in a straight or branched chain,
C
8-C
15 alkyl toluene sulfonates and C
8-C
15 alkyl phenol sulfonates.
[0050] A preferred sulfonate is linear alkyl benzene sulfonate having a high content of
3- (or higher) phenyl isomers and a correspondingly low content (well below 50%) of
2- (or lower) phenyl isomers, that is, wherein the benzene ring is preferably attached
in large part at the 3 or higher (for example, 4, 5, 6 or 7) position of the alkyl
group and the content of the isomers in which the benzene ring is attached in the
2 or 1 position is correspondingly low. Particularly preferred materials are set forth
in U.S. Patent 3,320,174.
[0051] Other suitable anionic surfactants are the olefin sulfonates, including long-chain
alkene sulfonates, long-chain hydroxyalkane sulfonates or mixtures of alkene sulfonates
and hydroxyalkane sulfonates. These olefin sulfonate detergents may be prepared in
a known manner by the reaction of sulfur trioxide (SO
3) with long-chain olefins containing 8 to 25, and having the formula RCH=CHR
1 where R is a higher alkyl group of 6 to 23 carbons and R
1 is an alkyl group of 1 to 17 carbons or hydrogen to form a mixture of sultones and
alkene sulfonic acids which is then treated to convert the sultones to sulfonates.
Olefin sulfonates contain from 14 to 16 carbon atoms in the R alkyl group and are
obtained by sulfonating an a-olefin.
[0052] Other examples of suitable anionic sulfonate surfactants are the paraffin sulfonates
containing 10 to 20. Primary paraffin sulfonates are made by reacting long-chain alpha
olefins and bisulfites and paraffin sulfonates having the sulfonate group distributed
along the paraffin chain are shown in U.S. Patents Nos.. 2,503,280; 2,507,088; 3,260,744;
3,372,188; and German Patent 735,096.
[0053] Examples of satisfactory anionic sulfate surfactants are the C
8-C
18 alkyl sulfate salts and the C
8-C
18 alkyl sulfate salts and the C
8-C
18 alkyl ether polyethenoxy sulfate salts having the formula R(OC
2H
4)
n OSO
3M wherein n is 1 to 12, and M is a solubilizing cation selected from the group consisting
of sodium, potassium, ammonium, magnesium and mono-, di- and triethanol ammonium ions.
The alkyl sulfates may be obtained by sulfating the alcohols obtained by reducing
glycerides of coconut oil or tallow or mixtures thereof and neutralizing the resultant
product. On the other hand, the alkyl ether polyethenoxy sulfates are obtained by
sulfating the condensation product of ethylene oxide with a C
8-C
18 alkanol and neutralizing the resultant product. The alkyl sulfates may be obtained
by sulfating the alcohols obtained by reducing glycerides of coconut oil or tallow
or mixtures thereof and neutralizing the resultant product. On the other hand, the
alkyl ether polyethenoxy sulfates are obtained by sulfating the condensation product
of ethylene oxide with a C
8-C
18 alkanol and neutralizing the resultant product. The alkyl ether polyethenoxy sulfates
differ from one another in the number of moles of ethylene oxide reacted with one
mole of alkanol. Preferred alkyl sulfates and preferred alkyl ether polyethenoxy sulfates
contain 10 to 16 carbon atoms in the alkyl group.
[0054] The C
8-C
12 alkylphenyl ether polyethenoxy sulfates containing from 2 to 6 moles of ethylene
oxide in the molecule also are suitable for use in the inventive compositions. These
detergents can be prepared by reacting an alkyl phenol with 2 to 6 moles of ethylene
oxide and sulfating and neutralizing the resultant ethoxylated alkylphenol.
[0055] Obviously, these anionic surfactants will be present either in acid form or salt
form depending upon the pH of the final composition, with salt forming cation being
the same as for the other anionic detergents.
[0056] Of the foregoing non-soap anionic surfactants, the preferred surfactants are the
C
9-C
15 linear alkylbenzene sulfonates and the C
13-C
17 paraffin or alkane sulfonates. Particularly, preferred compounds are sodium C
10-C
13 alkylbenzene sulfonate and sodium C
13-C
17 alkane sulfonate.
[0057] Generally, the proportion of the nonsoap-anionic surfactant will be in the range
of 0.1% to 20.0%, by weight of the dilute o/w microemulsion composition.
[0058] The instant composition contains a composition (herein after referred to as ethoxylated
glycerol type compound) which is a mixture of a fully esterified ethoxylated polyhydric
alcohol, a partially esterified ethoxylated polyhydric alcohol and a nonesterified
ethoxylated polyhydric alcohol, wherein the preferred polyhydric alcohol is glycerol,
and the compound is:
and
wherein w equals one to four. B is selected from the group consisting of hydrogen
or a group represented by:
wherein R is selected from the group consisting of alkyl group having 6 to 22 carbon
atoms, and alkenyl groups having 6 to 22 carbon atoms, wherein a hydrogenated tallow
alkyl chain or a coco alkyl chain is most preferred, wherein at least one of the B
groups is represented by said
and R' is selected from the group consisting of hydrogen and methyl groups; x, y
and z have a value between 0 and 60, provided that (x+y+z) equals 2 to 100, wherein
in Formula (I) the ratio of monoester / diester / triester is 45 to 90 / 5 to 40 /
1 to 20, wherein the ratio of Formula (I) to Formula (II) is a value between 3 to
0.02, wherein it is most preferred that there is more of Formula (II) than Formula
(I) in the mixture that forms the compound.
[0059] The ethoxylated glycerol type compound used in the instant composition is manufactured
by the Kao Corporation and sold under the trade name LEVENOL™ such as Levenol F-200
which has an average EO of 6 and a molar ratio of coco fatty acid to glycerol of 0.55
or LEVENOL™ V501/2 which has an average EO of 17 and a molar ratio of tallow fatty
acid to glycerol of 1.0. It is preferred that the molar ratio of the fatty acid to
glycerol is less than 1.7, more preferably less than 1.5 and most preferably less
than 1.0. The ethoxylated glycerol type compound has a molecular weight of 400 to
1600, and a pH (50 grams / liter of water) of 5-7. The LEVENOL™ compounds are substantially
non irritant to human skin and have a primary biodegradabillity higher than 90% as
measured by the Wickbold method Bias-7d.
[0060] Two examples of the LEVENOL™ compounds are LEVENOL™ V-501/2 which has 17 ethoxylated
groups and is derived from tallow fatty acid with a fatty acid to glycerol ratio of
1.0 and a molecular weight of 1465 and LEVENOL™ F-200 has 6 ethoxylated groups and
is derived from coco fatty acid with a fatty acid to glycerol ratio of 0.55. Both
LEVENOL™ F-200 and Levenol™ V-501/2 are composed of a mixture of Formula (I) and Formula
(II). The LEVENOL™ compounds has ecoxicity values of algae growth inhibition > 100
mg/liter; acute toxicity for Daphniae > 100 mg/liter and acute fish toxicity > 100
mg/liter. The LEVENOL™ compounds have a ready biodegradability higher than 60% which
is the minimum required value according to OECD 301B measurement to be acceptably
biodegradable.
[0061] Polyesterified nonionic compounds also useful in the instant compositions are CROVOL™
PK-40 and CROVOL™ PK-70 manufactured by Croda GMBH of the Netherlands. CROVOL™ PK-40
is a polyoxyethylene (12) Palm Kernel Glyceride which has 12 EO groups. CROVOL™ PK-70
which is prefered is a polyoxyethylene (45) Palm Kernel Glyceride have 45 EO groups.
[0062] In the dilute o/w microemulsion compositions or liquid crystal compositions the ethoxylated
glycerol type compounds or the polyesterified nonionic compounds will be present in
admixture with the anionic detergent. The proportion of the ethoxylated glycerol type
compound or the polyesterified nonionic solubilizing agent based upon the weight of
the liquid crystal composition or the final dilute o/w microemulsion composition will
be 0.1% to 20%, by weight.
[0063] Furthermore, in the more preferred compositions the weight ratio of nonsoap anionic
detergent to the ethoxylated glycerol type compound will be in the range of 3:1 to
1:3 with especially good results being obtained at a weight ratio of 2:1.
[0064] The ethoxylated polyhydric alcohol such as an ethoxylated glycerol of the instant
invention is depicted by the following formula
wherein w equals one to four, x, y and z have a value between 0 and 60, provided
that (x+y+z) equals 2 to 100.
[0065] In the dilute o/w microemulsion compositions or liquid crystal compositions the ethoxylated
alcohol will be present in admixture with the anionic surfactant. The proportion of
the ethoxylated glycerol type based upon the weight of the liquid crystal composition
or the final dilute o/w microemulsion composition will be 0.1% to 20% by weight.
[0066] Furthermore, in the more preferred compositions the weight ratio of nonsoap anionic
surfactant to the ethoxylated polyhydric alcohol will be in the range of 3:1 to 1:3
with especially good results being obtained at a weight ratio of 2:1.
[0067] The instant composition can also contain 0 to 10 wt. %, of a monoester of an ethoxylated
polyhydric alcohol depicted by the formula
wherein w equals one to four. Two of the Bs are hydrogen and one B is selected from
the group consisting of a group represented by:
wherein R is selected from the group consisting of alkyl group having 6 to 22 carbon
atoms, and alkenyl groups having 6 to 22 carbon atoms, wherein a hydrogenated tallow
alkyl chain or a coco alkyl chain is most preferred, x, y and z have a value between
0 and 60, provided that (x+y+z) equals 2 to 100.
[0068] The instant composition can also contain 0 to 2 wt. %, of a diester of an ethoxylated
polyhydric alcohol depicted by the formula
wherein w equals one to four. One of the Bs is hydrogen and two Bs are selected from
the group consisting of a group represented by:
wherein R is selected from the group consisting of alkyl group having 6 to 22 carbon
atoms, and alkenyl groups having 6 to 22 carbon atoms, wherein a hydrogenated tallow
alkyl chain or a coco alkyl chain is most preferred, x, y and z have a value between
0 and 60, provided that (x+y+z) equals about 2 to 100.
[0069] The instant composition can also contain 0 to 1.0 wt. %, of a triester of an ethoxylated
polyhydric alcohol depicted by the formula
wherein w equals one to four. The three Bs are selected from the group consisting
of a group represented by:
wherein R is selected from the group consisting of alkyl group having 6 to 22 carbon
atoms, and alkenyl groups having 6 to 22 carbon atoms, wherein a hydrogenated tallow
alkyl chain or a coco alkyl chain is most preferred, x, y and z have a value between
0 and 60, provided that (x+y+z) equals 2 to 100.
[0070] The instant compositions contain 0.4 to 1.0 wt. % of a tri-alkyl citrate such as
tri-n-butyl citrate, tri-n-propyl citrate, tri-isopropyl citrate, tri-isobutyl citrate,
tri-n-pentyl citrate, tri-isopentyl citrate and tri-n-hexyl citrate, wherein tri-n-butyl
citrate is preferred. The tri-n-butyl citrate functions in the formula as a foam control
agent in that the foam is more readily collapsed such that the article can be rinsed
more effectively.
[0071] The cosurfactant may play an essential role in the formation of the dilute o/w microemulsion
and the concentrated microemulsion compositions. Three major classes of compounds
have been found to provide highly suitable cosurfactants for the microemulsion over
temperature ranges extending from 5°C to 43°C for instance; (1) water-soluble C
3-C
4 alkanols, polypropylene glycol of the formula HO(CH
3CHCH
2O)
nH wherein n is a number from 2 to 18 and monoalkyl ethers and esters of ethylene glycol
and propylene glycol having the structural formulas R(X)
nOH and R
1(X)
nOH wherein R is C
1-C6 alkyl, R
1 is C
2-C
4 acyl group, X is (OCH
2CH
2) or (OCH
2(CH
3)CH) and n is a number from 1 to 4; (2) aliphatic mono- and di-carboxylic acids containing
2 to 10 carbon atoms, preferably 3 to 6 carbons in the molecule; and (3) triethyl
phosphate. Additionally, mixtures of two or more of the four classes of cosurfactant
compounds may be employed where specific pH's are desired.
[0072] When the mono- and di-carboxylic acid (Class 2) cosurfactants are employed in the
instant microemulsion compositions at a concentration of 2 to 10 wt. %, the microemulsion
compositions can be used as a cleaners for bathtubs and other hard surfaced items,
which are acid resistant thereby removing lime scale, soap scum and greasy soil from
the surfaces of such items damaging such surfaces. If these surfaces are of zirconium
white enamel, they can be damaged by these compositions.
[0073] An aminoalkylene phophonic acid at a concentration of 0.01 to 0.2 wt. % can be optionally
used in conjunction with the mono- and di-carboxylic acids, wherein the aminoalkylene
phophonic acid helps prevent damage to zirconium white enamel surfaces. Additionally,
0.05 to 1 % of phosphoric acid can be used in the composition.
[0074] Methanol and ethanol are explicitly excluded from the instant composition because
of their low flash point.
[0075] Representative members of the polypropylene glycol include dipropylene glycol and
polypropylene glycol having a molecular weight of 200 to 1000, e.g., polypropylene
glycol 400. Other satisfactory glycol ethers are ethylene glycol monobutyl ether (butyl
cellosolve), diethylene glycol monobutyl ether (butyl carbitol), triethylene glycol
monobutyl ether, mono, di, tri propylene glycol monobutyl ether, tetraethylene glycol
monobutyl ether, propylene glycol tertiary butyl ether, ethylene glycol monoacetate
and dipropylene glycol propionate. When these glycol type cosurfactants are at a concentration
of at least 1.0 weight %, in combination with a perfume at a concentration of at least
0.5 weight %, one can form a liquid crystal composition
[0076] Representative members of the aliphatic carboxylic acids include C
3-C
6 alkyl and alkenyl monobasic acids and dibasic acids such as glutaric acid and mixtures
of glutaric acid with adipic acid and succinic acid, as well as mixtures of the foregoing
acids as well as acrylic acid or propionic acid.
[0077] While all of the aforementioned glycol ether compounds and acid compounds provide
the described stability, the most preferred cosurfactant compounds of each type, on
the basis of cost and cosmetic appearance (particularly odor), are diethylene glycol
monobutyl ether and a mixture of adipic, glutaric and succinic acids, respectively.
The ratio of acids in the foregoing mixture is not particularly critical and can be
modified to provide the desired odor. Generally, to maximize water solubility of the
acid mixture glutaric acid, the most water-soluble of these three saturated aliphatic
dibasic acids, will be used as the major component.
[0078] Generally, weight ratios of adipic acid: glutaric acid:succinic acid is 1-3:1-8:1-5,
can be used with equally good results.
[0079] Still other classes of cosurfactant compounds providing stable microemulsion compositions
at low and elevated temperatures are the mono-, di- and triethyl esters of phosphoric
acid such as triethyl phosphate.
[0080] The amount of cosurfactant required to stabilize the liquid crystal compositions
or the microemulsion compositions will, of course, depend on such factors as the surface
tension characteristics of the cosurfactant, the type and amounts of the primary surfactants
and perfumes, and the type and amounts of any other additional ingredients which may
be present in the composition and which have an influence on the thermodynamic factors
enumerated above. The amounts of cosurfactant in the range of from 0.5% to 15%, by
weight provide stable dilute o/w microemulsions for the above-described levels of
primary surfactants and perfume and any other additional ingredients as described
below.
[0081] As will be appreciated by the practitioner, the pH of the final microemulsion will
be dependent upon the identity of the cosurfactant compound, with the choice of the
cosurfactant being effected by cost and cosmetic properties, particularly odor. For
example, microemulsion compositions which have a pH in the range of 1 to 10 may employ
either the class 1 or the class 4 cosurfactant as the sole cosurfactant, but the pH
range is reduced to 1 to 8.5 when the polyvalent metal salt is present. On the other
hand, the class 2 cosurfactant can only be used as the sole cosurfactant where the
product pH is below 3.2. However, where the acidic cosurfactants are employed in admixture
with a glycol ether cosurfactant, compositions can be formulated at a substantially
neutral pH (e.g., pH 7±1.5).
[0082] The ability to formulate neutral and acidic products without builders which have
grease removal capacities is a feature of the present invention because the prior
art o/w microemulsion formulations most usually are highly alkaline or highly built
or both.
[0083] In addition to their excellent capacity for cleaning greasy and oily soils, the low
pH o/w microemulsion formulations also exhibit excellent cleaning performance and
removal of soap scum and lime scale in neat (undiluted) as well as in diluted usage.
[0084] The final essential ingredient in the inventive microemulsion compositions having
improved interfacial tension properties is water. The proportion of water in the microemulsion
compositions generally is in the range of 20% to 97%, by weight of the usual diluted
o/w microemulsion composition.
[0085] As believed to have been made clear from the foregoing description, the dilute o/w
microemulsion liquid all-purpose cleaning compositions of this invention are especially
effective when used as is, that is, without further dilution in water, since the properties
of the composition as an o/w microemulsion are best manifested in the neat (undiluted)
form. However, at the same time it should be understood that depending on the levels
of surfactants, cosurfactants, perfume and other ingredients, some degree of dilution
without disrupting the microemulsion, per se, is possible. For example, at the preferred
low levels of active surfactant compounds (i.e., primary anionic and nonionic surfactants)
dilutions up to 50% will generally be well tolerated without causing phase separation,
that is, the microemulsion state will be maintained.
[0086] However, even when diluted to a great extent, such as a 2- to 10-fold or more dilution,
for example, the resulting compositions are still effective in cleaning greasy, oily
and other types of soil. Furthermore, the presence of magnesium ions or other polyvalent
ions, e.g., aluminum, as will be described in greater detail below further serves
to boost cleaning performance of the primary detergents in dilute usage.
[0087] On the other hand, it is also within the scope of this invention to formulate highly
concentrated microemulsions which will be diluted with additional water before use.
[0088] The present invention also relates to a stable concentrated microemulsion or acidic
microemulsion composition comprising by weight:
(a) 1 to 30% of an anionic surfactant;
(b) 0.5 to 15% of an ethoxylated glycerol type compound;
(c) 2 to 30% of a cosurfactant;
(d) 0.4 to 10% of a water insoluble hydrocarbon or perfume;
(e) 0 to 18% of at least one dicarboxylic acid;
(f) 0 to 1% of phosphoric acid;
(g) 0 to 0.2% of an aminoalkylene phosphonic acid;
(h) 0 to 15% of magnesium sulfate heptahydrate;
(i) 0.4 to 1.0% of a tri-alkyl citrate; and
(h) balance being water, wherein the composition has an ecotoxocity as measured by
the LC 50 test of at least 0.18 ml/L measured on Daphniae microorganisms.
[0089] The present invention also relates to a stable acidic microemulsion composition comprising
by weight:
(a) 1 to 30% of an anionic surfactant;
(b) 0.5 to 15% of an ethoxylated glycerol type compound;
(c) 0 to 2.5% of a fatty acid;
(d) 2 to 30% of a cosurfactant;
(e) 0.5 to 10% of a water insoluble hydrocarbon or perfume;
(f) 0 to 15% of magnesium sulfate heptahydrate;
(g) 0.4 to 1.0% of a tri-alkyl citrate; and
(h) balance being water, wherein the composition has an ecotoxocity as measured by
the LC 50 test of at least 0.18 ml/L measured on Daphniae microorganisms.
[0090] The present invention also relates to a stable concentrated microemulsion or acidic
microemulsion composition comprising by weight:
(a) 1 to 30% of an anionic surfactant;
(b) 0.5 to 15% of an ethoxylated polyhydric alcohol such as an ethoxylated glycerol;
(c) 2 to 30% of a cosurfactant;
(d) 0.4 to 10% of a water insoluble hydrocarbon or perfume;
(e) 0 to 18% of at least one dicarboxylic acid;
(f) 0 to 1 % of phosphoric acid;
(g) 0 to 0.2% of an aminoalkylene phosphonic acid;
(h) 0 to 15% of magnesium sulfate heptahydrate;
(i) 0.4 to 1.0 % of a tri-alkyl citrate; and
(j) the balance being water.
[0091] The present invention also relates to a stable acidic microemulsion composition comprising
by weight:
(a) 1 to 30% of an anionic surfactant;
(b) 0.5 to 15% of an ethoxylated polyhydric alcohol such as an ethoxylated glycerol;
(c) 2 to 30% of a cosurfactant;
(d) 0.5 to 10% of a water insoluble hydrocarbon or perfume;
(e) 0 to 15% of magnesium sulfate heptahydrate;
(f) 0.4 to 1.0 % of a tri-alkyl citrate; and
(f) the balance being water.
[0092] Such concentrated microemulsions can be diluted by mixing with up to 20 times or
more, their weight of water to form o/w microemulsions similar to the diluted microemulsion
compositions described above. While the degree of dilution is suitably chosen to yield
an o/w microemulsion composition after dilution, it should be recognized that during
the course of dilution both microemulsion and non-microemulsions may be successively
encountered.
[0093] In addition to the above-described essential ingredients required for the formation
of the microemulsion composition, the compositions of this invention may often and
preferably do contain one or more additional ingredients which serve to improve overall
product performance.
[0094] One such ingredient is an inorganic or organic salt of oxide of a multivalent metal
cation, particularly Mg
++. The metal salt or oxide provides several benefits including improved cleaning performance
in dilute usage, particularly in soft water areas, and minimized amounts of perfume
required to obtain the microemulsion state. Magnesium sulfate, either anhydrous or
hydrated (e.g., heptahydrate), is especially preferred as the magnesium salt. Good
results also have been obtained with magnesium oxide, magnesium chloride, magnesium
acetate, magnesium propionate and magnesium hydroxide. These magnesium salts can be
used with formulations at neutral or acidic pH since magnesium hydroxide will not
precipitate at these pH levels.
[0095] Although magnesium is the preferred multivalent metal from which the salts (inclusive
of the oxide and hydroxide) are formed, other polyvalent metal ions also can be used
provided that their salts are nontoxic and are soluble in the aqueous phase of the
system at the desired pH level. Thus, depending on such factors as the pH of the system,
the nature of the primary surfactants and cosurfactant, and so on, as well as the
availability and cost factors, other suitable polyvalent metal ions include aluminum,
copper, nickel, iron, calcium, etc. It should be noted, for example, that with the
preferred paraffin sulfonate anionic detergent calcium salts will precipitate and
should not be used. It has also been found that the aluminum salts work best at pH
below 5 or when a low level, for example 1 weight percent, of citric acid is added
to the composition which is designed to have a neutral pH. Alternatively, the aluminum
salt can be directly added as the citrate in such case. As the salt, the same general
classes of anions as mentioned for the magnesium salts can be used, such as halide
(e.g., bromide, chloride), sulfate, nitrate, hydroxide, oxide, acetate, propionate,
etc.
[0096] In the dilute compositions the metal compound is added to the composition in an amount
sufficient to provide at least a stoichiometric equivalence between the anionic surfactant
and the multivalent metal cation. For example, for each gram-ion of Mg++ there will
be 2 gram moles of paraffin sulfonate, alkylbenzene sulfonate, etc., while for each
gram-ion of A1
3+ there will be 3 gram moles of anionic surfactant. Thus, the proportion of the multivalent
salt generally will be selected so that one equivalent of compound will neutralize
from 0.1 to 1.5 equivalents, of the acid form of the anionic surfactant.
[0097] At higher concentrations of anionic surfactant, the amount of multivalent salt will
be in range of 0.5 to 1 equivalents per equivalent of anionic surfactant.
[0098] The o/w microemulsion compositions comprises from 0% to 2.5%, by weight of the composition
of a C8-C
22 fatty acid or fatty acid soap as a foam suppressant. The addition of fatty acid or
fatty acid soap provides an improvement in the rinseability of the composition whether
applied in neat or diluted form. Generally, however, it is necessary to increase the
level of cosurfactant to maintain product stability when the fatty acid or soap is
present. If more than 2.5wt % of the fatty acid is used in the instant compositions,
the composition will become unstable at low temperatures as well as having an objectionable
smell.
[0099] As example of the fatty acids which can be used as such or in the form of soap, mention
can be made of distilled coconut oil fatty acids, "mixed vegetable" type fatty acids
(e.g. high percent of saturated, mono-and/or polyunsaturated C
18 chains); oleic acid, stearic acid, palmitic acid, eiocosanoic acid, and the like,
generally those fatty acids having from 8 to 22 carbon atoms being acceptable.
[0100] The all-purpose liquid cleaning composition of this invention may, if desired, also
contain other components either to provide additional effect or to make the product
more attractive to the consumer. The following are mentioned by way of example: Colors
or dyes in amounts up to 0.5% by weight; bactericides in amounts up to 1% by weight;
preservatives or antioxidizing agents, such as formalin, 5-bromo-5-nitro-dioxan-1,3;
5-chloro-2-methyl-4-isothaliazolin-3-one, 2,6-di-tert.butyl-p-cresol, etc., in amounts
up to 2% by weight; and pH adjusting agents, such as sulfuric acid or sodium hydroxide,
as needed. Furthermore, if opaque compositions are desired, up to 4% by weight of
an opacifier may be added.
[0101] The instant compositions of the instant invention explicitly exclude zwitterionic
surfactant such as betaines because these zwetterionic surfactants are extremely high
foaming which, if used in the instant composition, would cause the instant compositions
to have to high a foam profile and that too much foam would leave residue on the surface
being cleaned.
[0102] In final form, the all-purpose liquids are clear oil-in-water microemulsions and
exhibit stability at reduced and increased temperatures. More specifically, such compositions
remain clear and stable in the range of 5°C to 50°C. Such compositions exhibit a pH
in the acid or neutral range depending on intended end use. The liquid microemulsion
compositions are readily pourable and exhibit a viscosity in the range of 6 to 60
milliPascal. second (mPas.) as measured at 25°C. with a Brookfield RVT Viscometer
using a #1 spindle rotating at 20 RPM.
[0103] The compositions are directly ready for use or can be diluted as desired and in either
case no or only minimal rinsing is required and substantially no residue or streaks
are left behind. Furthermore, because the compositions are free of detergent builders
such as alkali metal polyphosphates they are environmentally acceptable and provide
a better "shine" on cleaned hard surfaces.
[0104] When intended for use in the neat form, the liquid compositions can be packaged under
pressure in an aerosol container or in a pump-type sprayer for the so-called spray-and-wipe
type of application.
[0105] Because the compositions as prepared are aqueous liquid formulations and since no
particular mixing is required to form the o/w microemulsion, the compositions are
easily prepared simply by combining all the ingredients in a suitable vessel or container.
The order of mixing the ingredients is not particularly important and generally the
various ingredients can be added sequentially or all at once or in the form of aqueous
solutions of each or all of the primary detergents and cosurfactants can be separately
prepared and combined with each other and with the perfume. The magnesium salt, or
other multivalent metal compound, when present, can be added as an aqueous solution
thereof or can be added directly. It is not necessary to use elevated temperatures
in the formation step and room temperature is sufficient.
[0106] The instant microemulsion formulas explicitly exclude alkali metal silicates and
alkali meta builders such as alkali metal polyphosphates, alkali metal carbonates,
alkali metal phosphonates and alkali metal citrates because these materials, if used
in the instant composition, would cause the composition to have a high pH as well
as leaving residue on the surface being cleaned.
[0107] It is contemplated within the scope of the instant invention that the ethoxylated
glycerol type compound can be employed in hard surface cleaning compositions such
as wood cleaners, window cleaners and light duty liquid cleaners, wherein improvements
in a grease release effect in desirable.
[0108] The following examples illustrate liquid cleaning compositions of the described invention.
Unless otherwise specified, all percentages are by weight. The exemplified compositions
are illustrative only and do not limit the scope of the invention. Unless otherwise
specified, the proportions in the examples and elsewhere in the specification are
by weight. such as alkali metal polyphosphates they are environmentally acceptable
and provide a better "shine" on cleaned hard surfaces.
[0109] When intended for use in the neat form, the liquid compositions can be packaged under
pressure in an aerosol container or in a pump-type sprayer for the so-called spray-and-wipe
type of application.
[0110] Because the compositions as prepared are aqueous liquid formulations and since no
particular mixing is required to form the o/w microemulsion, the compositions are
easily prepared simply by combining all the ingredients in a suitable vessel or container.
The order of mixing the ingredients is not particularly important and generally the
various ingredients can be added sequentially or all at once or in the form of aqueous
solutions of each or all of the primary detergents and cosurfactants can be separately
prepared and combined with each other and with the perfume. The magnesium salt, or
other multivalent metal compound, when present, can be added as an aqueous solution
thereof or can be added directly. It is not necessary to use elevated temperatures
in the formation step and room temperature is sufficient.
[0111] The instant microemulsion formulas explicitly exclude alkali metal silicates and
alkali meta builders such as alkali metal polyphosphates, alkali metal carbonates,
alkali metal phosphonates and alkali metal citrates because these materials, if used
in the instant composition, would cause the composition to have a high pH as well
as leaving residue on the surface being cleaned.
[0112] It is contemplated within the scope of the instant invention that the ethoxylated
glycerol type compound can be employed in hard surface cleaning compositions such
as wood cleaners, window cleaners and light duty liquid cleaners, wherein improvements
in a grease release effect in desirable.
[0113] The following examples illustrate liquid cleaning compositions of the described invention.
Unless otherwise specified, all percentages are by weight. The exemplified compositions
are illustrative only and do not limit the scope of the invention. Unless otherwise
specified, the proportions in the examples and elsewhere in the specification are
by weight.
Example 1 (Reference)
[0114] The following compositions in wt. % were prepared:
|
A |
B |
C |
D |
E |
F |
Mr. Proper |
St Marc Lemon |
Sodium C13-C17 Paraffin sulfonate |
4.7 |
4.3 |
4 |
4.3 |
14.1 |
7.05 |
2.9 |
- |
EO/PO nonionic |
- |
- |
- |
- |
- |
- |
- |
3.2 |
Levenol F-200 |
2.3 |
2.2 |
2 |
2.2 |
6.3 |
3.45 |
- |
- |
C13-C15 EO 14 nonionic |
- |
- |
- |
- |
- |
- |
3.3 |
- |
DEGMBE |
4 |
4 |
3.5 |
4 |
12 |
6 |
4.4 |
3 |
Fatty acid |
0.75 |
0.5 |
0.4 |
0.75 |
2.25 |
1.125 |
0.65 |
0.3 |
MgSO4 7 H2O |
2.2 |
|
1.9 |
2.2 |
6.3 |
3.15 |
- |
- |
Perfume (a) |
0.8 |
0.75 |
0.9 |
0.7 |
2.4 |
1.2 |
present |
present |
Sodium Citrate |
- |
- |
- |
- |
- |
- |
3.2 |
- |
Water |
Bal |
Bal |
Bal |
Bal |
Bal |
Bal |
Bal |
Bal |
pH |
7 |
7 |
7 |
7 |
7 |
7 |
9.5 |
7 |
Degreasing test
Neat (b)
Dilute (b) |
30
45 |
35
60 |
35
60 |
35
60 |
30
45 |
30
45 |
70
>90 |
>100
90 |
Residue |
Equal to ref. |
Equal to ref. |
Equal to ref. |
Equal to ref. |
Equal to ref. |
Equal to ref. |
Worse |
Equal to ref. |
Foam in hard Water |
Equal to ref. |
Equal to ref. |
Equal to ref. |
Equal to ref. |
Equal to ref. |
Equal to ref. |
Equal to ref. |
Equal to ref. |
LC50-Ecotoxicity on Daphniae (c) |
0.18 ml/l |
- |
- |
- |
- |
- |
0.1 ml/l |
0.033 ml/l |
|
G |
H |
I |
Linear alkyl benzene sulfonic acid |
4.7 |
4.5 |
5 |
NaOH to reach pH 7 |
0.6 |
0.57 |
0.64 |
Levenol F-200 |
2.3 |
2.5 |
2 |
DEGMBE |
5.6 |
6 |
6.2 |
Fatty acid |
0.75 |
0.75 |
0.75 |
MgSO4 7 H2O |
2.15 |
2.06 |
2.3 |
Perfume (a) |
0.8 |
0.8 |
0.8 |
Water |
Bal |
Bal |
Bal |
pH |
7 |
7 |
7 |
(a) contains 25% by weight of terpenes.
(b) the lower the number of strokes, the better the degreasing performance.
(c) the higher the results, the lower the ecotoxicity.
[0115] Furthermore, "dissolution power" of the o/w microemulsion of this example is compared
to the "dissolution power" of an identical composition except that an equal amount
(5 weight percent) of sodium cumene sulfonate hydrotrope is used in place of the diethylene
glycol monobutyl ether cosurfactant in a test wherein equal concentrations of heptane
are added to both compositions. The o/w microemulsion containing the diethylene glycol
monobutyl ether solubilizes 12 grams of the water immiscible substance as compared
to 1.4 grams in the hydrotrope containing liquid composition.
[0116] In a further comparative test using blue colored cooking oil--a fatty triglyceride
soil --, the composition of Example 1 is clear after the addition of 0.2 grams of
cooking oil whereas the cooking oil floats on the top of the composition containing
the sulfonate hydrotrope.
[0117] When the concentration of perfume is reduced to 0.4% in the composition of Example
1, a stable o/w microemulsion composition is obtained. Similarly, a stable o/w microemulsion
is obtained when the concentration of perfume is increased to 2% by weight and the
concentration of cosurfactant is increased to 6% by weight in Example 1.
Example 2 (Reference)
[0118] The example illustrates a typical formulation of a "concentrated" o/w microemulsion:
|
% by weight |
Coco fatty acid |
4 |
Sodium C13-C17 Paraffin Sulfonate |
20.75 |
Levenol F-200 |
12 |
Diethylene glycol monobutyl ether |
20 |
Perfume (a) |
12.5 |
Water |
Bal to 100 |
pH: 7.0 ± 0.2 |
[0119] This concentrated formulation can be easily diluted, for example, five times with
tap water, to yield a diluted o/w microemulsion composition. Thus, by using microemulsion
technology it becomes possible to provide a product having high levels of active detergent
ingredients and perfume, which has high consumer appeal in terms of clarity, odor
and stability, and which is easily diluted at the usual usage concentration for similar
all-purpose hard surface liquid cleaning compositions, while retaining its cosmetically
attractive attributes.
[0120] Naturally, these formulations can be used, where desired, without further dilution
and can also be used at full or diluted strength to clean soiled fabrics by hand or
in an automatic laundry washing machine.
Example 3 (Reference)
[0121] This example illustrates a diluted o/w microemulsion composition having an acidic
pH and which also provides improved cleaning performance on soap scum and lime scale
removal as well as for cleaning greasy soil.
|
% by weight |
Sodium C13-C17 paraffin sulfonate |
4.7 |
Levenol F-200 |
2.3 |
Mg SO4 7H2O |
2.2 |
Mixture of succinic acid/glutaric acid/adipic acid (1:1:1) |
5 |
Perfume (d) |
1.0 |
Water, minors (dye) |
balance to 100 |
Phosphonic acid |
0.2 |
Amino tris - (methylene-phosphonic acid) |
0.03 |
pH = 3 ± 0.2 |
(d) contains 40% by weight of terpene
Example 4 (Reference)
[0122] Formula A of Example I was tested for the removal of a combination of grease and
particulate soil as well as for a grease release effect and compared to commercial
Ajax
tm NME
I. Grease + particulate soil removal;
Test Method
A) Soil composition:
[0123]
70 g of mineral oil
35 g of particulate soil (vacuum cleaner dust + 1 % of carbon black)
35 g C2Cl4
B) Soil preparation:
[0124]
- Weigh cleaned/dried glass tiles
- Soil the tiles with the grease + particulate soil
- Bake the tiles 1 hour at 80°C
- Weigh the soiled tiles which aged 2 hours at RT.
C) Soil removal:
[0125] The soiled tiles are soaked for 15 minutes at RT in the test products, then they
are delicately rinsed with tap water.
After drying 45 minutes at 50°C, the tiles are weighed again.
Results
[0126]
|
|
Grease + particulate soil |
% of removal mean of 6 tiles |
Commercial Ajaxtm NME |
|
60 |
Formula A of Example I |
|
95 |
[0127] Formula A exhibits improved grease + particulate soil removal over the Commercial
Ajax
tm NME
II. Grease release effect
Test Method
A) Soil composition:
[0128]
20% hardened tallow
80% beef tallow
fat blue dye
B) Soil preparation:
[0129] The fat mixture is heated and sprayed with an automatic spraying device on cleaned
and dried ceramic tiles.
C) Soil removal:
[0130] Product used neat: 2.5 g on sponge
Product used dilute: 1.2% sol in tap water - 10 ml of the solution on the sponge
The cleaning procedure is done with the gardner device for both product concentrations.
Results
A) On treated ceramic tiles (treated with the product before spraying the soil)
[0131]
|
Neat |
Dilute |
|
Number of Strokes |
First grease layer deposition |
mean of 4 tiles |
mean of 6 tiles |
Commercial Current Ajaxtm NME |
27 |
19 |
|
19 |
5* |
Second grease layer deposition on the same tile |
mean of 4 tiles |
mean of 6 tiles |
Commercial Ajaxtm NME |
25 |
48 |
|
25 |
18* |
B) On untreated ceramic tiles
[0132] In addition to the previous test, the 3 following procedures were used to verify
that Formula A remains on the surface after rinsing or wiping. After the first cleaning
procedure and before the second spraying:
1) the tiles were allowed to dry in open air
2) the surface was wiped with paper towel
3) the surface was rinsed with wet sponge
1) dry in open air
|
Neat |
Dilute |
|
Number of Strokes |
First grease layer deposition |
mean of 4 tiles |
mean of 6 tiles |
Commercial Ajaxtm NME |
29 |
30 |
Formula A |
27 |
32 |
Second grease layer deposition on the same tile |
mean of 4 tiles |
mean of 6 tiles |
Commercial Ajaxtm NME |
33 |
21 |
Formula A |
30 |
6* |
2) wipe dry the surface
|
Neat |
Dilute |
|
Number of Strokes |
First grease layer deposition |
mean of 4 tiles |
mean of 6 tiles |
Commercial Ajaxtm NME |
29 |
30 |
Formula A |
27 |
32 |
Second grease layer deposition on the same tile |
mean of 4 tiles |
mean of 6 tiles |
Commercial Ajaxtm NME |
35 |
46 |
Formula A |
30 |
48.5 |
3) wet wiping the surface
|
Neat |
Dilute |
|
Number of Strokes |
First grease layer deposition |
mean of 4 tiles |
mean of 6 tiles |
Commercial Ajaxtm NME |
29 |
30 |
Formula A |
27 |
32 |
Second grease layer deposition on the same tile |
mean of 4 tiles |
mean of 6 tiles |
Commercial Ajaxtm NME |
34 |
58 |
Formula A |
27 |
41 ** |
* highly significant difference
** after 5 strokes, 65% of the grease is already removed |
[0133] These results clearly demonstrate the important grease release effect obtained with
Formula A especially when the product is used dilute.
Example 5 (Reference)
[0134] The following optically clear microemulsion compositions were made by forming first
a solution by mixing at 25°C water, magnesium lauryl ether sulfate, Levenol V-510/2
and 1-Pentanol. To this solution with mixing at 25°C was added the dodecane to form
the optically clear microemulsion. The formula are expressed in weight percent.
|
A |
B |
C |
D |
E |
F |
G |
H |
I |
Magnesium Lauryl sulfate |
7 |
2.04 |
3.04 |
4.99 |
3.01 |
6.38 |
5.01 |
4.02 |
2.99 |
Levenol V-501/2 |
3.2 |
8.15 |
7.1 |
5.1 |
7.06 |
3.9 |
5.06 |
6.24 |
7.2 |
1-Pentanol |
1.19 |
1.03 |
4.1 |
4.05 |
5.05 |
5.67 |
1.07 |
1.05 |
1.13 |
Dodecane |
1.29 |
0.73 |
17.36 |
11.26 |
20.07 |
15.2 |
2.86 |
3.05 |
2.9 |
water |
Bal |
Bal |
Bal |
Bal |
Bal |
Bal |
Bal |
Bal |
Bal |
|
Example 6
[0135] The following composition was prepared by simple mixing procedure:
Sodium C13-C17 |
4.0 |
Paraffin Sulfonate |
|
Levenol F-200 |
2.0 |
DEGMBE |
4.5 |
Fatty Acid |
0.5 |
MgSO4·7H2O |
1.8 |
Perfume(a) |
0.8 |
tri-n-butyl citrate |
0.5 |
Water |
Balance |
pH |
7 |
Degreasing test |
|
Neat (6) |
|
Dilute (6) |
|
Residue |
|
Foam in hand |
|
Water |
|
(a) contains 25% by weight of terpenes
(b) the lower the number of strokes, the better the degreasing performance. |
[0136] The addition of the tri-n-butyl citrate improves the rinsability of the surface being
rinsed in that the collapse of the foam is improved as compared to a composition not
containing the tri-n-butyl citrate.
[0137] In summary, the described invention broadly relates to an improvement in microemulsion
compositions containing an anionic surfactant, an ethoxylated glycerol type compound,
a fatty acid, one of the specified cosurfactants, a hydrocarbon ingredient and water
which comprise the use of a water-insoluble, odoriferous perfume as the essential
hydrocarbon ingredient in a proportion sufficient to form either a dilute o/w microemulsion
composition or liquid crystal composition containing, by weight, 0.1 % to 20.0% of
an anionic detergent, 0.1 % to 20% of an ethoxylated glycerol type compound, 0.1%
to 50% of cosurfactant, 0.4 to 1.0% of a tri-alkyl citrate, 0.1% to 10% of perfume
and the balance being water.
Example 7 (Reference)
[0138] The following compositions in wt. % were prepared:
|
A |
B |
C |
D |
E |
F |
Na C13-17 paraffin sulfonate |
4.7 |
4.7 |
4.7 |
4.7 |
4.7 |
4.7 |
DEGMBE |
4 |
4 |
4 |
4 |
4 |
4 |
Coco fatty acid |
0.75 |
0.75 |
0.75 |
0.75 |
0.75 |
0.75 |
MgSO4 |
2.2 |
2.2 |
2.2 |
2.2 |
2.2 |
2.2 |
Perfume |
0.8 |
0.8 |
0.8 |
0.8 |
0.8 |
0.8 |
Compound (a) |
0.023 |
0.017 |
0.011 |
0.006 |
-- |
-- |
Compound (b) |
0.115 |
0.086 |
0.058 |
0.028 |
-- |
-- |
Compound (c) |
0.897 |
0.673 |
0.449 |
0.224 |
-- |
-- |
Compound (d) |
1.265 |
1.525 |
1.78 |
2.066 |
2.3 |
-- |
Neodol 91-5 |
-- |
-- |
-- |
-- |
-- |
2.3 |
Water |
Bal. |
Bal. |
Bal. |
Bal. |
Bal. |
Bal. |
Phase behavior |
One phase |
One phase |
One phase |
One phase |
One phase |
One phase |
Particulate soil (Kaolin removal |
71.0 |
79.8 |
84.0 |
86.0 |
88.7 |
51.0 |
Compound (a) is
[0139]
wherein R
1, R
2 and R
3 are coco alkyl chains
Compound (b) is
[0140]
wherein R
4 and R
5 are coco alkyl chains
Compound (c) is
[0141]
wherein R
6 is a coco alkyl chain
Compound (d) is
[0142]
[0143] In summary, the described invention broadly relates to an improvement in microemulsion
compositions for the removal of particulate soil containing an anionic surfactant,
an ethoxylated polyhydric alcohol a cosurfactant, a hydrocarbon ingredient and water
which comprise the use of a water-insoluble, odoriferous perfume as the essential
hydrocarbon ingredient in a proportion sufficient to form either a dilute o/w microemulsion
composition containing, by weight, 0.1% to 20% of an anionic detergent, 0.1% to 20.0%
of an ethoxylated polyhydric alcohol, 0.1% to 50% of cosurfactant, 0.1% to 10% of
perfume, 0.4 to 1.0 % of a tri-alkyl citrate and the balance being water.
[0144] In summary, the described invention broadly relates to an improvement in microemulsion
compositions containing an anionic surfactant, an esterified polyethoxyether nonionic
surfactant, a fatty acid, one of the specified cosurfactants, a hydrocarbon ingredient,
a tri-alkyl citrate and water which comprise the use of a water-insoluble, odoriferous
perfume as the essential hydrocarbon ingredient in a proportion sufficient to form
either a dilute o/w microemulsion composition or liquid crystal composition containing,
by weight, 0.1% to 20% of an anionic detergent, 0.1% to 20.0% of a solubilizing agent
which is an ethoxylated glycerol type compound, 0.1% to 50% of cosurfactant, 0.4%
to 10% of perfume 0.4 to 1.0 % of a tri-alkyl citrate and the balance being water.