Note: Descriptions are shown in the official language in which they were submitted.
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MILD ANTIBACTERIAL LIQUID DISH CLEANING COMPOSITIONS CONTAINING
PEROXIDE HAVING IMPROVED STABILITY AND STAIN REMOVAL BENEFITS
Field of Invention
This invention relates to a mild antibacterial liquid dish cleaning
composition of
high active surfactant level containing APG and higher betaine levels and
hydrogen
peroxide, having improved stability which is designed to disinfect and remove
stains,
from the surface been treated while maintaining good foaming grease cutting,
rinsing
and mildness properties.
Background of the Invention
The present invention relates to novel light duty liquid detergent
compositions
containing APG and higher betaine levels, and hydrogen peroxide with an
improved
stability profile and high foaming and good grease cutting properties as well
as
disinfecting properties.
The prior art is replete with tight duty liquid detergent compositions
containing
nonionic surfactants in combination with anionic and/or betaine surfactants
wherein the
nonionic detergent is not the major active surtactant. In U.S. Patent No.
3,658,985 an
anionic based shampoo contains a minor amount of a fatty acid alkanolamide.
U.S.
Patent No. 3,769,398 discloses a betaine-based shampoo containing minor
amounts of
nonionic surfactants. This patent states that the low foaming properties of
nonionic
detergents renders its use in shampoo compositions non-preferred. U.S. Patent
No.
4,329,335 also discloses a shampoo containing a betaine surfactant as the
major
ingredient and minor amounts of a nonionic surfactant and of a fatty acid mono-
or di-
ethanolamide. U.S. Patent No. 4,259,204 discloses a shampoo comprising 0.8 to
20%
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by weight of an anionic phosphoric acid ester and one additional surfactant
which may
be either anionic, amphoteric, or nonionic. U.S. Patent No. 4,329,334
discloses an
anionic-amphoteric based shampoo containing a major amount of anionic
surfactant
and lesser amounts of a betaine and nonionic surfactants.
U.S. Patent No. 3,935,129 discloses a liquid cleaning composition containing
an
alkali metal silicate, urea, glycerin, triethanolamine, an anionic detergent
and a nonionic
detergent. The silicate content determines the amount of anionic and/or
nonionic
detergent in the liquid cleaning composition. However, the foaming properties
of these
detergent compositions are not discussed therein.
U.S. Patent No. 4,129,515 discloses a heavy duty liquid detergent for
laundering
fabrics comprising a mixture of substantially equal amounts of anionic and
nonionic
surfactants, alkanolamines and magnesium salts, and, optionally, zwitterionic
surfactants as suds modifiers.
U.S. Patent No. 4,224,195 discloses an aqueous detergent composition for
laundering socks or stockings comprising a specific group of nonionic
detergents,
namely, an ethylene oxide of a secondary alcohol, a specific group of anionic
detergents, namely, a sulfuric ester salt of an ethylene oxide adduct of a
secondary
alcohol, and an amphoteric surfactant which may be a betaine, wherein either
the
anionic or nonionic surfactant may be the major ingredient.
The prior art also discloses detergent compositions containing all nonionic
surfactants as shown in U.S. Patent Nos. 4,154,706 and 4,329,336 wherein the
shampoo compositions contain a plurality of particular nonionic surfactants in
order to
affect desirable foaming and detersive properties despite the fact that
nonionic
surfactants are usually deficient in such properties.
U.S. Patent No. 4,013,787 discloses a piperazine based polymer in conditioning
and shampoo compositions which may contain all nonionic surfactant or all
anionic
surfactant.
U.S. Patent No. 4,450,091 discloses high viscosity shampoo compositions
containing a blend of an amphoteric betaine surfactant, a
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polyoxybutylenepolyoxyethylene nonionic detergent, an anionic surfactant, a
fatty acid
alkanolamide and a polyoxyalkylene glycol fatty ester. But, none of the
exemplified
compositions contain an active ingredient mixture wherein the nonionic
detergent is
present in major proportion which is probably due to the low foaming
properties of the
polyoxybutylene polyoxyethylene nonionic detergent.
U.S. Patent No. 4,595,526 describes a composition comprising a nonionic
surfactant, a betaine surfactant, an anionic surfactant and a C12-C14 fatty
acid
monoethanolamide foam stabilizer.
U.S. Patent 6,147,039 teaches an antibacterial hand cleaning composition
having a low surfactant content.
Summary of the Invention
It has now been found that a mild, antibacterial liquid dish cleaning
composition
containing APG and higher betaine levels, and hydrogen peroxide having
improved
stability can be formulated with three different anionic surfactants, a
zwitterionic
surfactant, an alkyl glucoside surfactant, a hydroxy aliphatic acid, a
solubilizer, a
preservative, and water which has desirable cleaning and foaming properties.
An object of this invention is to provide an antibacterial liquid dish
cleaning
composition which comprises a sulfate surfactant, two sulfonate anionic
surfactants, a
zwitterionic surfactant, an alkyl polyglucoside surfactant, a solubilizer, a
hydroxy
aliphatic acid, hydrogen peroxide, a preservative and water, wherein the
composition
does not contain any amine oxide, peracetic acid, polyethylene glycol, glycol
ether,
silicas, abrasives, acyl isoethionate, 2-hydroxy-4,2',4'-trichloridiphenyl
ether,
phosphoric acid, phosphonic acid, boric acid, alkali metal carbonates,
alkaline earth
metal carbonates, alkyl glycine surfactant, cyclic imidinium surfactant, or
more than 3
wt. % of a fatty acid or salt thereof.
Another object of this invention is to provide a mild antibacterial liquid
dish
cleaning composition having improved stability and with desirable high foaming
and
cleaning properties which kills bacteria and removes stains from surfaces.
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Additional objects, advantages and novel features of the invention will be set
forth in part in the description which follows, and in part will become
apparent to those
skilled in the art upon examination of the following or may be learned by
practice of the
invention. The objects and advantages of the invention may be realized and
attained
by means of the instrumentalities and combinations particularly pointed out in
the
appended claims.
Detailed Description of the Invention
This invention relates to an antibacterial liquid dish cleaning composition
with
stain removal properties, which comprises approximately by weight:
(a) 1 % to 9% of a sodium salt of a Cg-C1 g linear alkyl benzene sulfonate
surfactant;
(b) 4% to 16% of a magnesium salt of a Cg-C1 g linear alkyl benzene
sulfonate surfactant;
(c) 4% to 16% of an ammonium or sodium salt of an ethoxylated Cg-C1 g
alkyl ether sulfate surfactant;
(d) 0.1 % to 8% of a zwitterionic surfactant;
(e) 0.5% to 5%, more preferably 0.5% to 4% of a hydroxy containing organic
acid;
(f) 5% to 15% of an alkyl polyglucoside surfactant;
(g) 0.1 % to 10%, more preferably 0.5% to 10% of at least one solubilizer;
(h) 0.005% to 3.0% of a preservative;
(i) 0.1 % to 5%, more preferably 0.2% to 4%of hydrogen peroxide; and
(j) the balance being color, fragrance, UV absorber and water, wherein the
composition has a pH of 3 to 4.5 and has a viscosity of 200 to 800 cps, more
preferably
200 to 600 cps at 25°C using a #21 spindle at 20 rpm as measured on a
Brookfield
RVTDV-II viscometer, wherein the composition does not contain any grease
release
agents such as choline chloride or buffering system which is a nitrogerious
buffer which
is ammonium or alkaline earth carbonate, amine oxide surfactants, peracetic
acid,
polyethylene glycol, glycol ether, guanidine derivates, alkoxylalkyl amines
and
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alkyleneamines C3-C7 alkyl and alkenyl monobasic and dibasic acids such as C4-
C7
aliphatic carboxylic diacids which do not contain a hydroxy group, boric acid,
phosphoric acid, ethoxylated nonionic surfactants and amino alkylene
phosphonic acid.
The anionic sulfonate surfactants which may be used in the detergent of this
5 invention are selected from the consisting of water soluble and include the
sodium,
potassium, ammonium, magnesium and ethanolammonium salts of linear Cg-C1 g
alkyl
benzene sulfonates; C1 p-C20 paraffin sulfonates, alpha olefin sulfonates
containing
about 10-24 carbon atoms and Cg-C1 g alkyl sulfates and mixtures thereof.
The paraffin sulfonates may be monosulfonates or di-sulfonates and usually are
mixtures thereof, obtained by sulfonating paraffins of 10 to 20 carbon atoms.
Preferred
paraffin sulfonates are those of C12-18 carbon atoms chains, and more
preferably they
are of C14-17 chains. Paraffin sulfonates that have the sulfonate groups)
distributed
along the paraffin chain are described in U.S. Patents 2,503,280; 2,507,088;
3,260,744; and 3,372,188; and also in German Patent 735,096. Such compounds
may
be made to specifications and desirably the content of paraffin sulfonates
outside the
C14-17 range will be minor and will be minimized, as will be any contents of
di- or poly-
sulfonates.
Examples of suitable other sulfonated anionic detergents are the well known
higher alkyl mononuclear aromatic sulfonates, such as the higher alkylbenzene
sulfonates containing 9 to 18 or preferably 9 to 16 carbon atoms in the higher
alkyl
group in a straight or branched chain, or Cg-15 alkyl toluene sulfonates. A
preferred
alkylbenzene sulfonate is a linear alkylbenzene sulfonate having a higher
content of 3-
phenyl (or higher) isomers and a correspondingly lower content (well below
50%) of 2-
phenyl (or lower) isomers, such as those sulfonates wherein the benzene ring
is
attached mostly 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. Preferred materials are set forth in U.S.
Patent
3,320,174, especially those in which the alkyls are of 10 to 13 carbon atoms.
The Cg_1 g ethoxylated alkyl ether sulfate surfactants have the structure
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- +
R-(OCHCH2)nOSOgM
wherein n is about 1 to about 22 more preferably 1 to 3 and R is an alkyl
group having
about 8 to about 18 carbon atoms, more preferably 12 to 15 and natural cuts,
for
example, C12-14 or C12-16 and M is an ammonium cation or a metal cation, most
preferably sodium.
The ethoxylated alkyl ether sulfate may be made by sulfating the condensation
product of ethylene oxide and Cg-10 alkanol, and neutralizing the resultant
product.
The ethoxylated alkyl ether sulfates differ from one another in the number of
carbon
atoms in the alcohols and in the number of moles of ethylene oxide reacted
with one
mole of such alcohol. Preferred ethoxylated alkyl ether polyethenoxy sulfates
contain
12 to 15 carbon atoms in the alcohols and in the alkyl groups thereof, e.g.,
sodium
myristyl (3 EO) sulfate.
Ethoxylated Cg-1 g alkylphenyl ether sulfates containing from 2 to 6 moles of
ethylene oxide in the molecule are also suitable for use in the invention
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.
The concentration of the ethoxylated alkyl ether sulfate surfactant is about 1
to about 8
wt. %.
The water-soluble zwitterionic surfactant, which is an essential ingredient of
present liquid detergent composition, provides good foaming properties and
mildness
to the present nonionic based liquid detergent. The zwitterionic surfactant is
a water
soluble betaine having the general formula:
R2
R1---,~Rz~. COO-
RS
wherein R1 is an alkyl group having 10 to 20 carbon atoms, preferably 12 to 16
carbon
atoms, or the amido radical:
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R ~-----N---(CH
2~"
wherein R is an alkyl group having 9 to 19 carbon atoms and a is the integer 1
to 4; R2
and Rg are each alkyl groups having 1 to 3 carbons and preferably 1 carbon; R4
is an
alkylene or hydroxyalkylene group having from 1 to 4 carbon atoms and,
optionally, one
hydroxyl group. Typical alkyldimethyl betaines include decyl dimethyl betaine
or 2-(N-
decyl-N, N-dimethyl-ammonia) acetate, coco dimethyl betaine or 2-(N-coco N, N-
dimethylammonio) acetate, myristyl dimethyl betaine, palmityl dimethyl
betaine, lauryl
diemethyl betaine, cetyl dimethyl betaine, stearyl dimethyl betaine, etc. The
amidobetaines similarly include cocoamidoethylbetaine, cocoamidopropyl betaine
and
the like. A preferred betaine is coco (Cg-C1 g) amidopropyl dimethyl betaine.
The alkyl polysaccharides surfactants, which are used in conjunction with the
aforementioned surfactants have a hydrophobic group containing from about 8 to
about
20 carbon atoms, preferably from about 10 to about 16 carbon atoms, most
preferably
from about 12 to about 14 carbon atoms, and polysaccharide hydrophilic group
containing from about 1.5 to about 10, preferably from about 1.5 to about 4,
most
preferably from about 1.6 to about 2.7 saccharide units (e.g., galactoside,
glucoside,
fructoside, glucosyl, fructosyl; andlor galactosyl units). Mixtures of
saccharide moieties
may be used in the alkyl polysaccharide surfactants. The number x indicates
the
number of saccharide units in a particular alkyl polysaccharide surfactant.
For a
particular alkyl polysaccharide molecule x can only assume integral values. In
any
physical sample of alkyl polysaccharide surfactants there will be in general
molecules
having different x values. The physical sample can be characterized by the
average
value of x and this average value can assume non-integral values. In this
specification
the values of x are to be understood to be average values. The hydrophobic
group (R)
can be attached at the 2-, 3-, or 4- positions rather than at the 1-position,
(thus giving
e.g. a glucosyl or galactosyl as opposed to a glucoside or galactoside).
However,
attachment through the 1- position, i.e., glucosides, galactoside,
fructosides, etc., is
preferred. In the preferred product the additional saccharide units are
predominately
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attached to the previous saccharide unit's 2-position. Attachment through the
3-, 4-,
and 6- positions can also occur. Optionally and less desirably there can be a
polyalkoxide chain joining the hydrophobic moiety (R) and the polysaccharide
chain.
The preferred alkoxide moiety is ethoxide.
Typical hydrophobic groups include alkyl groups, either saturated or
unsaturated, branched or unbranched containing from about 8 to about 20,
preferably
from about 10 to about 18 carbon atoms. Preferably, the alkyl group is a
straight chain
saturated alkyl group. The alkyl group can contain up to 3 hydroxy groups
and/or the
polyalkoxide chain can contain up to about 30, preferably less than about 10,
alkoxide
moieties.
Suitable alkyl polysaccharides are decyl, dodecyl, tetradecyl, pentadecyl,
hexadecyl, and octadecyl, di-, tri-, tetra-, penta-, and hexaglucosides,
galactosides,
lactosides, fructosides, fructosyls, lactosyls, glucosyls and/or galactosyls
and mixtures
thereof.
The alkyl monosaccharides are relatively less soluble in water than the higher
alkyl polysaccharides. When used in admixture with alkyl polysaccharides, the
alkyl
monosaccharides are solubilized to some extent. The use of alkyl
monosaccharides in
admixture with alkyl polysaccharides is a preferred mode of carrying out the
invention.
Suitable mixtures include coconut alkyl, di-, tri-, tetra-, and
pentaglucosides and tallow
alkyl tetra-, penta-, and hexaglucosides.
The preferred alkyl polysaccharides are alkyl polyglucosides having the
formula
R20(CnH2n0)r(~)x
wherein 2 is derived from glucose, R is a hydrophobic group selected from the
group
consisting of alkyl, alkylphenyl, hydroxyalkylphenyl, and mixtures thereof in
which said
alkyl groups contain from about 10 to about 18, preferably from about 12 to
about 14
carbon atoms; n is 2 or 3 preferably 2, r is from 0 to 10, preferable 0; and x
is from 1.5
to 8, preferably from 1.5 to 4, most preferably from 1.6 to 2.7. To prepare
these
compounds a long chain alcohol (R20H) can be reacted with glucose, in the
presence
of an acid catalyst to form the desired glucoside. Alternatively the alkyl
polyglucosides
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can be prepared by a two step procedure in which a short chain alcohol (R1 OH)
can be
reacted with glucose, in the presence of an acid catalyst to form the desired
glucoside.
Alternatively the alkyl polyglucosides can be prepared by a two step procedure
in which
a short chain alcohol (C1 _6) is reacted with glucose or a polyglucoside (x=2
to 4) to
yield a short chain alkyl glucoside (x=1 to 4) which can in turn be reacted
with a longer
chain alcohol (R20H) to displace the short chain alcohol and obtain the
desired alkyl
polyglucoside. If this two step procedure is used, the short chain
alkylglucosde content
of the final alkyl polyglucoside material should be less than 50%, preferably
less than
10%, more preferably less than about 5%, most preferably 0% of the alkyl
polyglucoside.
The amount of unreacted alcohol (the free fatty alcohol content) in the
desired
alkyl polysaccharide surfactant is preferably less than about 2%, more
preferably less
than about 0.5% by weight of the total of the alkyl polysaccharide. For some
uses it is
desirable to have the alkyl monosaccharide content less than about 10%.
The used herein, "alkyl polysaccharide surfactant" is intended to represent
both
the preferred glucose and galactose derived surfactants and the less preferred
alkyl
polysaccharide surfactants. Throughout this specification, "alkyl
polyglucoside" is used
to include alkyl polyglycosides because the stereochemistry of the saccharide
moiety is
changed during the preparation reaction.
An especially preferred APG glycoside surfactant is APG 625 glycoside
manufactured by the Henkel Corporation of Ambler, PA. APG25 is a nonionic
alkyl
polyglycoside characterized by the formula:
CnH2n+1 O(C6H 1005)xH
wherein n=10 (2%); n=122 (65%); n=14 (21-28%); n=16 (4-8%) and n=18 (0.5%) and
x
(degree of polymerization) = 1.6. APG 625 has: a pH of 6 to 10 (10% of APG 625
in
distilled water); a specific gravity at 25°C of 1.1 g/ml; a density at
25°C of 9.1 Ibs/gallon;
a calculated HLB of 12.1 and a Brookfield viscosity at 35°C, 21
spindle, 5-10 RPM of
3,000 to 7,000 cps.
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The hydroxy containing organic acid is ortho hydroxy benzoic acid or
preferably
a hydroxy aliphatic acid selected from the group consisting of lactic acid,
citric acid,
salicylic acid and glycolic and mixtures thereof, wherein citric acid is
preferred.
The instant light duty liquid nonmicroemulsion compositions can contain about
0
5 wt. % to about 10 wt. %, more preferably about 1 wt. % to about 8 wt. %, of
at least one
solubilizing agent selected from the group consisting of a C2-5 mono,
dihydroxy or
polyhydroxy alkanols such as ethanol, isopropanol, glycerol ethylene glycol,
diethylene
glycol, propylene glycol, and hexylene glycol and mixtures thereof and alkali
metal
cumene or xylene sulfonates such as sodium cumene sulfonate and sodium xylene
10 sulfonate. The solubilizing agents are included in order to control low
temperature
cloud clear properties.
The instant formulas explicitly exclude alkali metal silicates and alkali
metal
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.
The final essential ingredient in the inventive compositions having improved
interfacial tension properties is water. The proportion of water in the
compositions
generally is in the range of 10% to 95%.
The 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; UV
absorbents, or antioxidizing agents, 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.
Preservatives which can be used in the instant compositions at a concentration
of 0.005 wt. % to 3 wt. %, more preferably 0.01 wt. % to 2.5 wt. % are:
benzalkonium
chloride; benzethonium chloride,5-bromo-5-nitro-1,3dioxane; 2-bromo-2-
nitropropane-
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1,3-diol; alkyl trimethyl ammonium bromide; N-(hydroxymethyl)-N-(1,3-dihydroxy
methyl-2,5-dioxo-4-imidaxolidinyl-N'-(hydroxy methyl) urea; 1-3-dimethyol-5,5-
dimethyl
hydantoin; formaldehyde; iodopropynl butyl carbamata, butyl paraben; ethyl
paraben;
methyl paraben; propyl paraben, mixture of methyl isothiazolinone/methyl-
chloroisothiazoline in a 1:3 wt. ratio; mixture of phenoxythanol/butyl
paraben/methyl
paraben/propylparaben; 2-phenoxyethanol; tris-hydroxyethyl-hexahydrotriazine;
methylisothiazolinone; 5-chloro-2-methyl-4-isothiazolin-3-one; 1,2-dibromo-2,
4-
dicyanobutane; 1-(3-chloroalkyl)-3,5,7-triaza-azoniaadamantane chloride; and
sodium
benzoate. PH adjusting agents such as sulfuric acid or sodium hydroxide can be
used
as needed.
In final form, the instant compositions exhibit stability at reduced and
increased
temperatures. More specifically, such compositions remain clear and stable in
the
range of 0°C to 50°C, especially 5°C to 43°C. Such
compositions exhibit a pH of 3 to
5.
The following examples illustrate the liquid body 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.
The instant compositions have a minimum foam volume of 350m1s after 40
rotations at room temperature as measured by the foam volume test using 0.0333
wt.
of the Ultra composition in 150 ppm of water. The Shake foam test is an
inverted
cylinder test in which 100 gr. of a 0.0333 wt. % LDL formula in 150 ppm of H20
is
placed in a stoppered graduate cylinder (500 ml) and inverted 40 cycles at a
rate of 30
cycles/minute. After 40 inversions, the foam volume which has been generated
is
measured in mls inside the graduated cylinder. This value includes the 100 ml
of LDL
solution inside the cylinder. After the initial volume is measured, 175
microliters of
whole milk is added to the solution. The cylinder is then inverted for another
40 cycles
and a foam volume with soil is measured; the foam volume after the soil
addition is at
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least 130m1s. The values provided above include the 100 ml's of LDL solution
inside
the cylinder.
Example 1
The following compositions are listed as a wt. %. The physical properties and
appearance (i.e. viscosity, cloud point, color) are unchanged upon aging in
extreme
temperature conditions.
A _B _C
M Las 9 9 g
NaLas 3 3 3
EOS 1.3 EO 11.5 11.5 11.5
PG 9.5 9.5 9.5
Cocamido ro I betaine 5 5 5
GI coserve LAD 0.11 0.11 0.11
SXS 3.5 3.5 3.5
Ethanol 1.3 1.3 1.3
Citric acid 1 - -
Lactic acid - 1.4 -
H dro en eroxide 0.5 0.5 0.5
ino ard-TL UV absorber0.05 0.05 0.05
Perfume 0.45 0.45 0.45
ater balance balance balance
PH 3.2-3.6 3.2-3.6 6.8
stain removal (10%conc.33.1 32.5 12.5
l5min
soakin time
eroxide loss, 3 da 14% 18%
s C 135F
i% peroxide loss, 2 45% 64% Not applicable
weeksC~135F
The stain removal was determined on commercially available tea stained
melamine tiles fabricated by Test Fabrics Corp. The % removal was measured
by a Photovolt meter for quantitative results. A solution of either 1 % or 10%
dish
liquid was tested at room temperature and the soaking time was equal to 1
hour.
The experimental conditions can be varied between 15 minutes and 1 hour
soaking time, Room Temperature or 115oF. The dilution can also be lowered to
1 %. In addition to tea tiles, coffee tiles can be used to exhibit the
superiority in
stain removal
