Note: Descriptions are shown in the official language in which they were submitted.
BACXGROUND OF THE INVENTION
This invention relates to detergent cleaning com-
positions which are particularly suitable for use in auto-
matic dishwashers. In detail, the compositions herein comprise
an alkoxylated nonionic surface-active agent, an aromatic sul-
fonated compatibilizing agent, a mixture of an alkali sulfateand an alkali sulfite, and are free of chlorine-containing
bleach components. Both the nonionic surface-active
'.'' ~.
~50313~
agent and the compatibilizing agent are present in major
amounts, preferably in about equiponderal quantities.
The mixture of alkali sulfite and alkali sulfate is used
in a major amount in a well-defined and narrow weight ratio.
The compositions herein provide, during conventional use,
marke~ly enhanced anti-redeposition benefits, particularly
for soils composed of grease and grease-protein complexes.
The instant compositions are also capable of pxoviding im-
proved cleaning benefits especially for burned-on soils.
In addition to the essential components listed, the subject
compositions preferably comprise conventional dishwashing
composition additives in the art-established levels for
their known functions. Examples of the like additive in-
clude sodium silicate solids, sodium carbonate, sodium bi-
carbonate and sodium phosphate.
Convantional automatic dishwashing compositionsnormally contain a low-foaming surface-active agent, a
chlorine bleach, alkaline builder materials, and usual minor
ingredients and additives. The incorporation of chlorine
bleaches re~uires special processing and storage p~ecautions
to protect components which are sub~ect to detarioration
upon direct contact with active chlorine. In addition, the
stability of the chlorine bleach itself i~ critical and
raises addition~l processing and storage difficulties. It
is also known that the chlorine-containing bleaches which
are normally used in automatic dishwashing detergent co~posi-
tionscan tarnish silverware and damage the metal trim on china.
Accordingly, there is a standing desire to formulate auto-
matic dishwashing detergent compositions w~ich are free of
active chlorine and which
~q)3~
are capable of pro~iding overall hard surface cleaning and
appearance benefits comparable to or better than active
chlorine-containing detergent ~ompositions. This reformu-
lation is particularly delicate considering that during
automatic dishwashing operations, active chlorine prevenks
the formation and/or deposition of troublesome proteins
and prote~n-grease complexes on the hard surfaces and no
surfactant is currently known capable of performing that
function in the absence of chlorine bleach.
The majority of detergent compositions presently
available contain inert filler salts such as sodium sulfate
in varying levels up to, for example, 80%. U.S. Patent
2,387,572 to Flett discloses that the detergent activity
of alkylaryl sulfonates containing from 12 to 16 carbon
atoms can be enhanced by the addition thereto of substantial
amounts of a water-solu~le salt having an inorganic cation
selected from the group consisting of water-soluble sulfates,
sulfites, thiosulfates, chlorides~ dihydrogen phosphates,
borates and acetates. U.S. Patent 3,741,901 to Ziffer dis-
eloses detergent compositions containing surfaee-active
agents and chelating agents, if desired, in combination with
additional detergent composition additives and a water-sol-
uble sulfite or bisulfite.
~5~)31~
The disclosures of U.S. Patent 3,549,539 to
Mallows relate to machine dishwash:ing powders containing
a nonylphenol-5-EO or a condensation product of a random
C~ to C15 secondary alcohol and ethylene oxide with an
HLB (hydrophilic-lipophilic balance) value between 11.5
and 13.5 and a polyethylene oxide-polypropyleneoxide con-
densate that consists of between 5 and 25~ polyethyleneoxide
and 95 to 75% polypropyleneoxide and has a molecular weight
between 1500 and 2700. It is disclosed that, in addition
to the above surfactant combination, the machine dishwash-
ing powder will normally contain from 5 to 30~ of a silicate
;such as sodium metasilicate, from 5 to 30% of an oxidizing
agent, from 25 to 70% of a calcium-ion sequestrant and from
1 to 20~ of an inorganic filler salt, such as sodium car-
bonate or sodium sulfate. The oxidizing agents can be re-
presented by chlorinated sodium orthophosphate, chlorinated
isocyanurate and perborate possibly with a copper catalyst
or an organic activator. Additional disclosures relative
to bleach-containing detergent compositions for use in auto-
matic dishwashers can be found in, for example, U.S. Patents3,410,804; 3,390/092; 3,248,330 and 3~595,968.
Various attempts have also been made to formulate
bleach-free low-foaming detergsnt compositions for auto-
matic dishwashing machines containing particular low-foaming
nonionics, builders and filler materials and additives adapted
to provide a particular function. For example, U.S. Patent
3,022,250 to Grifo relates to low sudsing detergent compos-
itions especi~lly
~35~38~
.
adapted for use in automatic dishwashing machines con-
taining a phenol having therein an aliphatic substituent
with an ~ve~age of 9 carbon atoms per chain and a
second substituent comprising condensed ethylene oxide
in an average number of 4 molecules per molecule of
phenol together with builders consisting essentially
of a mixture of sodium metasilicate and sodium ~ripoly-
phosphate in ~le proportion of 1 part of metasilicate
to 3 parts of tripolyphosphate, t~e buildexs being
present in the proportion of 95 parts of builder mix-
ture to 5 parts of alkyl phenol ethylene oxide. The
disclosures of U.S. Patent 3,048~548 to Martin et al.
relate to substantially identical subject matter wherein
the nonionic low-foaming surface-active agent can be
represented by very specific polyoxyalkylene glycol
mixtures. U.S. Patent 3,382,178 to Lissant et al. also
pertains to automatic dishwashing compositions comprising
a de-foaming nonionic surfactant having a specific
formula and a small amount of an anti-oxidant for the
purpose of reducing, inhibiting and/or preventing alkali
degradation of the nonionic surfactant thereby rendering
it stable in alkaline detergents, particularly during
prolonged storage.
380
Canadian patent application Serial No.
227,094, filed May 15, 1975, said application being entitled:
AVTOMATIC VISHWASHING DETERGENT C~MPC)SITION; Inventor~:
~dwara J. Maguire, Jr. and Robert A. Staab; relates to
bleach-free detergent compositions for use i~ automatic
dishwashers comprising an alkoxylated nonionic surface-
active agent and a sulfonated aromatic compatibilizing
agent, such as, for example, xylene-, toluene-, cumene-
and benzenesulfonate.
Canadian Patent 1~024,461, granted January 17, 1978,
said patent being entitled:
ENZY~E--CONTAINING AUTOMATIC DISh~ASHING DET~:RGENT
COMPOSITION; Inventors: Geoffrey Place and Eaward J.
Maguire, Jr., relates to bleach-free automatic dish-
washing compositions ~omprising an alkoxylated nonionic
surface-active agent, a sulfonated aromatic compatibilizing
agent such as, for example, xylene-, toluene-, cumene-
and benzenesulfonate, and an enzyme having an iso-eleotric
pvint greater than 8.5.
~ hile the prior art clearly recognizes the
aisadvantages of using aggressive chlorine bleaches in
automatic dishwashing operations and also suggests bleach-
free compositions by merely leaving out the bleach
component, said art does not disclose or suggest c~mbina-
tions of alkoxylated nonionic surfactants and particular
-- 6 --
~4l ' ' .
~5~3~3~
compatibilizing agents in combination with well-defined
sulfate-sulfite mixtures, leave alone predictin~ the
perfor,mance advantages attainable when using the instant
compositionS in automatic dishwashing operations.,
It is an object of this invention to provide
bleach-free detergent compositions which can be used'
i~ automatic dishwashing operations.
It is-an additional o~ject of thi~s in~ention'
to provide an automatic dishwasning detergent composi-,
tion wnich exhi~its improved anti-redeposition character-
istics for soils composed of grease and grease-protein
complexes, and superior cleaning performance, particularly
for burned-on soils.
The above and other ob3ects can now be met by
formulating bleach-free detergent compositions comprisiny
a specific active s~stem and a combination of an alkali
sulfite and an alkali sulfate.
SUMMARY OF THE INV~NTION
.
This invention is, in part, based on the
discovery that excellent ~leach-free automatic ,,
dishwashing compositions can now be formulated
comprising a binary acti~e system and a combination
of water-soluble sulfates and sulfites. In more detail,
the composi~ion5 herein consi~t essentially of:
(a) from about 4% to about 20% ~y weight of
an alkoxylated nonionic surface~active
agent, wnerein said alkoxy moiety is
selected from the group consisting of
ethylene oxide; propylene oxide and
mixtures thereof;
.,.
-- 7 --
~05~)380
(b~ from about 5% to about 20% by weight of a ~ulfonated
aromatic compatibilizing agent having a criti.cal
micelle concentration greate:r than about 1% by weight/
volume at 25C., wherein the weight ratio of said
alkoxylated nonionic surface--active agent to said
sulfonated compatibilizing agent is in the range fr~m
about 2:5 to 5:3; and
(c) from about 15~ to about 60% by weight of a mixture of
(1) a water-soluble alkali metal sulfite, ammonium sulfite,
substituted ammonium sulfite, or mixtures thereof, and
(2) a water-soluble alkali metal sulfate,
ammonium sulfate, substituted ammonium sulfate or mixtures
thereof, said components being present in a weight ratio
of sulfite to sulfate from about 1:4 to about 2:1;
said composition being
substantially free of a chlorine bleach component.
In a preferred emboaiment of this invention, an
ethoxylated low-foaming nonionic ingredient is used in
combination with a compatibilizing agent selected from
the group consisting of toluene-, xylene-, cumene-,
benzene-, trimethylbenzene-, ethylbenzene-, ana ethyl-
methylbenzene sulonate and mixtures thereof. The
preferred weight ratio of the alkoxylated nonionic to
the compatibilizing agent is in the range from about
3:5 to about 5:4 9 especiall~ about 1:1. The binary
active system represents from about 9% to about ~0~,
especially from about 10~ to about 30~ of the detergent
composition. The sulfate-sulfite mixture is preferably
used in an amount from about 20% to about 40% by weight
having a preferred weight ratio of sulfite to sulfate
.
~q i
~5~38~
from about 1:2 to about 1:1. The p~ of a 0.3~ aqueous
solution of the detergent compositions herein has
preferably a pH above about 8.8, especially above about
g.8. ~
DETAILED ;)ESCRIPTION OF THE INVENTION
The automatic dishwashing detergent compositions
of t~is invention comprise (1) a binary active system;
(2) sulfite-sulfate mixture; and (3) are free of chlorine
~leach components. These essential parameters are dis-
cussed in detail nereinafter.
Unless stated to the contrary, the "percent"
indications stand for percent by weight.
The active component for use herein is represented
by a mixture of a surface~active alkoxylated nonionic and
a 5ulfonated aromatic compatibilizing agent. The binary
active mixture is used in an amount from about 9~ to about
40%, preferably from about 10% to about 30%. The wPight
ratio of alkoxylated nonionic surfactant to compatibilizing
agent is in the range from about 2:5 to about 5:3, pre-
ferably from about 3:5 to about 5:4, especially about 1:1.
The mixture of alkoxylated nonionic surfactant and
compatibilizing agent represents more than about 9%
to provide superior anti-redeposition and drainage per-
formance, thereby virtually eiiminating all residual
spots and streaks on the hard surfaces being cleaned.
Using less than about 9% of the active mixture creates
surface drainage problems and accordingly will adversely
affect the use of the subject compositions for the
~:35~)3~
intended purpose. The binary active system desirably
is kept below about 40~ o~ the granular detergent compos-
ition. Using more than about 40% may create suds problems
because of the particular characteristics of a gi~en non-
ionic, in addition such high levels of active system cancontrib~lte to lumping and caking tendency and also do not
provide additional performance ~enefits proportional to the
~increased active level.
As noted above, the performance advantages of
the compositions herein can only be achieved for a narrow
and specific weight ratio of alkoxylated nonionic surfactant
to compatibilizing agent. The weight ratio of the nonionic
ingredient to the compatibilizing ag~nt clearly reveals that
the latter is used as a major composition constituent. ~n
a highly preferred embodiment about e~uiponderal quantities
of the nonionic ingredient and the compatibilizer are used.
Variations in the weight ra~ios of the surfactant and the
compatibilizing agent outside of the ranges specified are
detractive to the attainment of the superior performance
supplied by the instant compositions. E~pecially, the rela-
tive amount of the compatibilizing agent becomes criticalwhen the weight ratio of alkoxylated nonionic to compatibil-
izing agent approaches about 5:3.
The alkoxylated nonionic detergent is used in an
amount of from about 4~ to about 20%. The alkoxy moiety is
selected ~rom the group consisting of ethylene oxide, pro-
pylene oxide and mixtures thereof. Ethylene oxide represents
the preferred reaction partner. The alkylene oxide moiety
is condensed with a nonionic base material according to tech-
niques known in the art. All alkoxylated nonionic detergents
-- 10 --
iL05~3~
~hich are normally known to ~e su~table for use in detergent
technology can be used hare~n~ Examples of the like components
~nclude:
~ 1~ The condensation product of one mole of a
saturated or unsaturatedl straight or branched chain car-
~oxylic acid having from about 10 to a~out 18 carbon atoms
~t~ from a~out 20 to a~out 50 moles, of ethylene oxide.
- T~e acid moiety can cons~st of mixtures of acid in the above
delineated carbon atoms range or it can consist of an acid
having a specific number of carbon atoms within this range.
T~e condensation p~oduct of one mole of coconut fatty acid
hav~ng the approximate carbon chain length distribution of
10~ 66% C12~ 23% C14 and 9% C16 with 35 moles of ethy-
lene oxide is a spec;fic example of a nonionic containing
a m~xture of different c~ain lengths fatty acid moieties.
Other specif~c examples of nonionics of this type are: the
condensation product of one mole of palmitic acid with 40
moles of ethylene oxide; the condensation product of one
mole-of myristic acid with 35 moles of ethylene oxide; the ~
2Q ~ condensation product of one mole of oleic acid with 45 moles
of et ~lene ox~de; and the condensation product of one mole
of stearic acid with 30 moles of ethylene oxide.
- (2) The condensation products of one mole of a
saturated or unsaturated, straight or branched chain al~ohol
having from about 10 to about 24 carbon atoms with from about
5 to a~out 50 moles of ethylene oxide. The alcohol moiety
can consist of mixtures of alcohols in the above~delineated
carbon atom range or ~t can consist of an alcohol haùing a
speclfic num~er of car~on atom~ wlthin this range. The
3Q condensat~on product o~ one mole of coconut alcohol having
t~e approx1~mate c~a~n length dlstr~butlon of 28% C10, 66% C12
--11~
~1~5~38C~
23% C14 and 9% C16 w~th 45 moles of ethylene oxide (CNAE45)
is a spec~ic example of a nonionic conta~ning a mixture of
different chain length alcohol moieties. Other specific
examples of nonionics of this type are the condensation pro-
ducts of one mole of tallow alcohol with from 6 to 20 moles
of ethylene oxide, the condensation products of one mole of
lauryl alcohol with 35 moles of ethylene oxide; the condensation
products of one mole of myristyl alcohol with 30 moles of
ethylene oxide; and the condensation products of one mole
~f oleyl alcohol with 40 moles of ethylene oxide.
t3) Polyethylene gly~ols having a molecular weight
of from about 1400 to about 30,000. For example, Dow Chemical
Company manufactures these nonionics in molecular weights of
--20j000, 9500, 7500, ~500, 3400, and 1450. All of these non-
~on~cs are wa~like solids which melt between 110F and 200F.
(4) The condensation products of one mole of alkyl
phenol wherein the alkyl chain contains from about 8 to about
18 car~on atoms with from about 4 to about 50 moles of ethylene
oxide. Specific examples of these nonionics are the conden-
2Q sation products of one mole of decyl phenol with 40 moles of
ethylene oxide; the condensation products of one mole of dodecyl
phenol with 35 moles of ethylene oxide; the condensation products
of one mole of tetradecyl phenol with 35 moles of ethylene oxide;
the condensation products of hexadecyl phenol with 30 moles of
ethylene oxide.
t5) The ethoxylated surfactants disclosed in
Canadian Patent Application Serial Number 222,185, filed
-Marc~ 17, 1975, inventor 3ero~e H. Coll~ns, consisting essen-
t~all~ of a m~xture of compounds ha~ng at least t~o levels
of ethylene ox~de add~tion and ~av~ng the formula:
- 12 ~
105~3~
Rl - R2 ~ (CH2CH20 ) nH
wherein Rl is a linear alkyl residue and R2 has the formula
-CHR3CH2-- ,,
wherein R3 is selected from *he group consisting of hydrogen
and mixtures thereof with not more than 40% by weight of
lower alkyl, wherein Rl and R2 together form an alkyl residue
having a mean chain length in the range of 8-15 carbon atoms,
at least 65% by weight of said residue having a chain length
within il carbon atom of the mean, wherein 3.5~ n~6.5, pro-
vided that the total amount of components in which n - 0 is
not greater than 5% by weight and the total amount of com-
ponents in which n = 2-7 inclusive is not less than 6B% by
weight, and the hydrophilic-lipophilic balance (HLB~ of said
ethoxylate material is in the range from 9.5-11.5, said sur-
factant composition being otherwise free of nonionic surfac-
tants having an HLB outside of said range.
Low-foaming alkoxylated nonionics are preferred
although other (than low-foaming) alkoxylated nonionics can
be used without departing frmm the spirit of this invention.
24 Examples of nonionic low~foaming surface-active components
include the condensation products of benzyl chloride and an
ethoxylated alkyl phenol wherein the alkyl group has from
about 6 to about 12 carbon atoms and wherein from about 12
to about 20 ethylene oxide molecules have been conden~ed per
mole of alkyl phenol; polyetheresters of the formula
(ClC~H4)2CHcO2(cH2-c~2-o)xR
wherein x is an integer from 4 to 20 and R is a lower alkyl
group containing not more than 4 carbon atoms, for example
a component having the formula
- 13 -
-
~I[)SC~3~0
(ClC6H4)2CHcO2(cH2cH2o)l5~c 3;
the polyalkoxylation products of alkyl phenol as, for ex-
ample, the polyglycol alkyl phenol ethers containing an
alkyl group having at least 6 and, normally, from about 8
to about 20 carbon atoms and having a molar ratio of ethyl-
ene oxide to condensate of about 7.5; 8.5; 11.5; 20.5 and
30. The alkyl group can, for example, be represented by
di-isobutylenè; di-amyl; polymerized propylene; iso-octyl;
and nonyl.
Addit~n~l examples of effective low-foaming non-
ionics include; the polyoxyalkylene glycol condensates of
U.S. Patent 3,043,548, of Martin et al., having alternating
hydrophilic oxyethylene chains and hydrophobic oxypropylene
chains wherein the weight of terminal hydrophobic chains,
the weight of the middle hydrophobi~ unit and the weight of
the linking hydrophilic units each represent about 1/3 of
the condensate, the de-foaming nonionic surfactants dis-
closed in U~S. Patent 3,382,178, of Lissant et al., having
the general formula
Zt(oR) O~
n -z
wherein Z is A-oxylatable material, A is the radical derived
from an alkylene oxide which can be ethylene and propylene
and ~ is an integer from for example 10 to 2000~or more and
z is an integer determined by the number of reactive o~yalkyl-
atable groups. Z can be represented by normal biodegradable
alcohols such as for example octane by reduction of fatty
acids derlved from coconut oil, palm kernel oil, tallow and
also those obtained from petroleum such as for example the
mixtures of C10 to C18 straight-chain primary alcohols; the
nonionic surface-act~ve agents of U.S. Patent 3,549~539 being
-- 1~ --
~051~38(;~
a mixture of nonylphenol-5-EO or the condensation product
of a random Cll to C15 secondary alcohol and ethylene ox.ide
where an HLB value between 11.5 and 13.5; and a polyethylene
oxide polypropylene oxide condensate that consists of be-
tween 5 and 25~ polyethylene oxide and 95 and 75% polypro-
pylene oxide and has a molecular waight between 1500 and
2700; the conjugated polyoxyalkylene compounds described in
U.S. Patent 2,677,700, corresponding to the formula:
Y(c3H6o)n(c2H4o)mH
wherein Y is the residue of organic compound having from
about 1 to 6 carbon. atoms and one reactive hydrogen atom,
n has an average value of at least about 6~4, as determined
by hydroxyl numbér ~nd m has a value such that the oxyethyl-
ene portion constitutes about 10 to 90 weight percent of the
molecule; the conjugated polyoxyalkylene compounds described
in U.S. Patent 2,674,619, having the formula
YC(C3H6O)n(C2H4O)m~ x
wherein Y is the residue of an organic compound having from
about 2 to 6 carbon atoms and containing x reactive hydro-
gen atoms in which x has a value of at least about 2, n
has a value such that the molecular weight of the polyoxy-
propylene hydrophobic base is at least about 900 and m has
a value such that the oxyethylene content of the molecule
is from about 10 to 90 weight percent. Compounds ~alling
within the scope of the definition for Y include, for example,
propylQne~glycol, glycerine, pentaerythritol, trimethylol-
propane, ethylene diamine and the like~ The oxypropylene
chains optionally, but advantageously, contain small amounts
of ethylene oxide and the oxyethylene chains also optionally,
but advantageously, contain small amounts of propylene oxide.
- 15 -
3L(~S038ClI
Additional conjugated polyoxyalkylene surface-
active agents which are advantageously used in the composi-
tions of this invention correspond to the formula:
P C(C3H60) n tC2EI4) mH~x
wherein P is the residue of an organic compound having
from about 8 to 18 carbon atoms and containing x reactive
hydrogen atoms in which x has a value of 1 or 2, n has a
value such that the molecular weight of the polyoxypropy-
lene portion is at least about 58 and ~ has a value such
that the oxyethylene content of the molecule is from about
10 to 90 weight percent and the formula:
P C(C2H4o)n(c3H6o)m ~x
wherein P is the residue of an organic compound having from
about 8 to 18 carbon atoms and containing x reactive hydro-
gen atoms in which x has a value of 1 or 2, n has a value
such that the molecular weight of the polyoxyethylene por-
tion is at least about 44 and m has a value such that the
oxypropylene content of the molecule`is from about 10 to 90
weight percent. In either case the oxypropylene chains may
contain optionally, but advantageously, small amounts of
ethylene oxide and the oxyethylene chains may contain also
optionally, but advantageously, small amounts of propylene
oxide.
Highly preferred alkoxylated nonionics for usé
herein include the condensation product of one mole of tallow
alcohol with from about 6 to about 15 moles, especially 9
moles of ethylene oxide; and also the alkoxylate commerciall
ly available under the trademark PLUR~DOT H~-433(R) Wyan-
dotte Chemical Corp~ which has a molecular weight in the
range ~fom 3700-4200. It contains about 3% monostearyl acid
- 16 -
- ~S()38(~1
phosphate suds suppressant.
Another essential component for use in the compos-
itions of this invention is a sulfonated aromatic compati-
bilizing agent having a critical micelle concentration great-
er than about 1~, preferably greater than about 2~ at 25C.
The compatibilizing agent is used in an amount of from about
5% to about 20%. As already pointed out hereinbefore, the
compatibilizing agent and the nonionic surface-active agents
are used in specific weight ratios to obtain the performance
advantages of the subject aomposltions.
The critical micelle concentration (CMC) is de-
termined by plotting the surface tension of a solution of
a particular compatibilizing agent versus the logarithm of
its concentration, all measurements being made at room temp-
erature (25~). The surface tension is measured accordingto the method set forth in`JOURNAL _ THE AMERICAN CHEMICAL
SOCIETY 52, 1751, (1930) by Harkins, W.D. and Jordan, H.E.
Various other techniques can also be used for measuring the
sur~ace tension of compatibilizing agents; for example,
light scattering measurements as described in NONIONIC SUR-
PACT~NTS, Chapter 16, Thermodynamics of Micelle Formation,
by Hall, D.G. and Pethica, B.A., pages 543-47, Marcel Dekker,
New York, 1967.
The critical micelle concentration of the compati-
bilizing agents herein, being greater than 1%, preferablygreater than 2~ (weight volume), denotes that during conven-
tional automatic dishwashing operations the detergent con-
centration being frequently in the range from about 0.1-
0.6%, this component does not act as a surface-active agent
in the art-established meaning for that term. It is also
- 17 -
~S~3~3~
noteworthy that the preferred compatibilizing agents are
known in detergent technology for their hydrotropic proper-
ties. In that prior art context, hydrotropes can be func-
tionally defined as being (organic) compounds having hydro-
phile-hydrophobe properties, and capable in high concentra-
tion of increasing the solubility of other organic compounds
in water or in aque~US~- salt solutions. Accordingly~ hydro-
tropes are used in liquid detergent compositions to aid and
augment the solubility of, for example, relatively high
levels of surface active agents and inorganic detergent build-
ers. The detergent compositions of this invention being
solid~ preferably granular, and easily soluble, (the term
soluble is meant to embrace dispersible) at the conventional
automatic dishwashing usage concentration (0.1%-0.6~), it
1~ is obvious that the hydrotrope functionality does not give
a clue to how the compatibilizing agent functions.
Apparently, however, and without being limited
as a result thereof, the compatibilizing agent aids in the
processes of soil wetting and hydrolysis on the surface. In
solution it facilitates soil dispersion and suspension with-
out interfering itself in the capti~e process. The compati-
bilizing agent can also provide interaction with dissolved
(dispersed) proteins to hold them in solution via surface-
active analogous properties and/or formation of mixed micelles.
The critical micelle concentration (CM¢) of sodium
cumene sulfonate is >2% at 25C while the nonionic ethylene
oxide-propylene oxide condensate commercially known as
"Pluradot HA-433" has-underiide~tical conditions a CMC of
0.002~ A mixture-o~f;sodium cumene sulfonate and UPluradot
~A-433" in e~ual-amounts~behaves~-ve~y much the s~me as the
nonionic by itsel~,~thus indicating-that
- 18 -
~C~5~3~
the compatibilizing agent has only a small, if any, effect
on the surface-active properties oE the nonionic.
As ~lready d~fined hereinbefore, the compatibil-
izing agent contains an aromatic and a sulfonate group. The
aromatic radical can, for example, be a benzene, a naphtha-
lene or a biphenyl radical, assuming its sulfonated deriva-
tive meets the CMC requirement set forth here~n. Commercial-
ly available examples of sulfonatable compatibilizing agent
precursors which can be used in the compositions of this
invention include benzene, toluene, xylene, cumene, tri-
methylbenzene, ethylbenzene and ethylmethylbenzene. Commer-
cial xylene is ~requently a mixture of ortho, meta and para
species. Similarly, trimethylbenzene can be represented by
1,2,3-trimethylbenzene or hemimellitene; 1,3,5-trimethyl-
benzene or mesitylene; and 1,2,4-trimethylbenzene or pseudo-
cumene. The above enumeration is not intended to be limit-
ing but a mere exemplification of suitable precursors~ Of
course, other sulfonatable precursors can qualify for use
in the compositions of the instant invention, provided these
compounds in sulfonated form meet with the definition herein,
especially the minimum critical micelle concentration. The
above organic precursors can be sulfonated according to
methods known in the art.
Preferred compatibilizing agents include the al-
kali metal salts of cumene sulfonate, ethylbenzene ~ulfonate,toluene sulfonate, benzene sulfonate, sylene sulfonate,
ethylmethylbenzene sulfonate, trimethylbenzene sulfonate
and mixtures thereof.
The compositions of this invention furthermore
comprise from about 15% to about 60% of a mixture o~ a water-
-- 19 --
~5~;)38~
soluble sulfite salt and a ~ater~soluble suIfate salt ~hereinthe weight ratio of sulfite to sulfate is from about 1:4 to
about 2:1. PreferaBly the sulfite-sulfate mixture represents
from a~out 20% to about 40% and the preferred weight ratio of
sulfite to sulfate ls from about 1:2 to about 1:1.
As used herein, th~ term "sulfite" is meant to
embrace water-soluble salts of feducing sulfureous containing
acids which by virtue of their stability and other character-
~stics can find application in the like compositions. Examples
lQ t~ereof include sodium sulfite (Na2SO3), sodium bisulfite
(NaHS03), sodium metbisulfate (Na2S203) and sodium dithionate
~Na2S2O6). The preparation of these sulfite ingredients is
~ell known and also they are readily available in commercial
quantities. So~ium sulfate is well known in detergent
tec~nology and used, as pointed out hereinbefore, in very
many commerically so~d compositions. Sodium sulfate is
pxepared, for ~xample, as a by-product of many chemical
- ~e~c~ons or it can be obta~ned by mining. The cations of
t~e water-solu~le salts can be represen$ed, for example,
2Q by alkali metal cations such as potassium, sodium, ~ithium,
ammonium, and organic cations including mono-, di-, and tri-
ethanolammonium, propylammonium, tetrabutylammonium, tetre-
methylammonium, tetraethylammonium, tetrapropylammonium,
met~ylammonium, and mixtures ~thereof. Cations which are
likely to form water-insoluble salts with the sulfite and/or
sulfate ions are less preferred for use hereinO The same
applies as well to ~i~alent metal ions which could contribute
to incxeaslng the water hàrdness.
T~e composlt~ons of th~s lnvention frequently com-
pr~se a sud~ suppress~ng agent for the purpose of inhibiting
t~e formation of e~cessive amounts of foam which can impair
~- 20 ~
319(~
the mechanical operation of the dishwashing machine due to
a lowering of the pressure at which the washing liquor is
impelled against the hard surfaces. Of course, the final
selection of the suds suppressing agent depends upon and
is required, in part, because of the qualitative and quan-
titative characteristics of the particular nonionic surface-
active agent which is utilized in the automatic dishwash-
ing compositions herein. In addition, food residues, espe-
cially proteinaceous food residue~, exhibit suds boosting
properties and therefore preferably command the presence
of an effective suds regulating agent.
Suds regulating components are normally used in
an amount from about 0.001% to about 5%, preferably from
about 0.05% to about 3% and especially from about 0.10% to
about 1%. The suds suppressing ~regulating) agents known
to be suitable as suds suppressing agents in detergent con-
text can be used in the compositions herein.
Preferred suds suppressin~ ad~itives are described
in Canadian Patent No. 1,004,566 granted February 1, 1977,
inventors Bartolotta et al., relative to a silicone suds
controlling agent. The silicone material can be represented
by alkylated polysiloxane materials such as silica aerogels
and xerogels and hydrophobic silicas of various types. The
silicone material can be described as siloxanes having the
formula:
~ lioJ x
R'
wherein x is from about 20 to about 2,000, and R and R' are
each alkyl or aryl groups, especially methyl, ethyl, propyl,
butyl and phenyl. The polydimethylsiloxanes (R and R' are
methyl) having a molecular weight within the range of from
about 200 to about 200,000, and higher, are all useful as
suds controlling agents. Additional suitable silicone mate-
rials wherein the side chain groups R and R' are alkyl, aryl,
or mixed alkyl and aryl hydrocarbyl groups exhibit useful
suds controlling properties. Examplés of the like ingredi-
ents include diethyl-, dipropyl-, dibutyl-, methylethyl-,
phenylmethyl-polysiloxanes and the like. Additional useful
silicone suds controlling agents can be represented by a
mixture of an alkylated~siloxane, as referrèd~to hereInbefo~e
and solid silica. Such mixtures are prepared by affixing
the silicone to the surface of the solid silica. A preferred
silicone suds controlling agent is represented by a hydro-
phobic silanated (most preferably trimethylsilanated) sili-
ca having a parti~le size in the range from about 10 milli-
microns to 20 millimicrons and a specific surface area above
about 50 m2/gm. intimately admixed with dimethyl silicone
fluid ha~ing a molecular weight in the range from about 500
to about 200,000 at a weight ratio of silicone to silanated
silica of from about 19:1 to about 1:2. The silicone suds
suppressing agent is advantageously rel~asably incorporated
in a water-soluble or water-dispersible, substantially non-
surface-active detergent-impermeable carrier.
Microcrystalline waxes having a melting p~int in
the range from 35C-115C and a saponification value of
less than 100 represent an additional example of a preferred
suds regulating component for use in the subject compositions.
The microcrystalline waxes are substantially water-insoluble,
but are water-dispersi~le in the presence of organic sur-
- 22 -
~5~38~
factants. Preferred microcrystalline waxes have a melting
point from about 65C to 1~0C, a molecular weight in the
range from 400-1,000; and a penetration value of at least
6, measured at 77F by ASTM-D1321. Suitable examples of
the above ~axes include: microcrystalline and oxidized mi-
crocrystalline petrolatum waxes; Fisher-Tropsch and oxidized
Fisher-Tropsch waxes; ozokerite; ceresin; montan wax; bees-
wax; candelilla; and carnauba wax.
Alkyl phosphate esters represent an additional
preferred suds suppressant for use herein. These preferred
phosphate esters are predominantly monostearyl phosphate
which, in addition thereto, can contain di- and tristearyl
phosphates and monool~l phosphates, which can contain di-
and trioleyl phosphates.
The alkyl phosphate esters fre~uently contain some
trialkyl phosphate. Accordingly, a preferred phosphate
ester can contain, in addition to the monoal~l ester, eOg.
monos~earyl phosphate, up to about 50 mole percent of di-
alkyl phosphate and up to about 5 mole percent of trialkyl
phosphateO
In addition to the components described herein-
before, the compositions according to this invention can
contain additional detergent composition ingredients which
are known to be suitable for use in automatic dishwashing
compositions in the art-established levels for their known
functions. Organic and inorganic detergent builder ingre-
dients, alkali materials, sequestering agents, china pro-
tecting agents, corrosion inhibitors, soil suspending ingre-
dients, drainage promoting ingredients, dyes, perfumes,
fillers, crystal modifiers and the like ingredients repre-
;, .
- 23 -
~5~3~
sent examples of functional classes of additional automatic
dishwashing composition additives. Suitable inorganic
builders include polyphosphates, for example tripolyphos-
phate, pyrophosphate or metaphosphate, carbonates, bicar-
bonates and alkali silicates. Examples of water-soluble or-
ganic builder components include the alkali metal salts of
polyacetates, carboxylates, polycarboxylates and polyhydroxy
sulfonates. Additional examples include sodium citrate,
sodium oxydisuccinate and sodium mellitate. Normally these
builder ingredients can be used in an amount up to 60%, pre-
ferably in the range from 10% to 50% by weight.
Suitable examples of sequestering agents include
alkali metal salts of ethylenediaminetetraacetic acid and
nitrilotriacetic acid.
Examples of china protecting agents include sil~
icates, water-soluble aluminosilicates and aluminates. Car-
boxymethylcellulose is a well-known soil suspending agent
for use in the like compositions whereas fillers are mostly
represented by sucrose, sucrose esters and the like,
~ 0.3% aqueous solution of the automatic dish-
washing detergent compositions herein preferably has a pH
which is greater than 8.8, especially greater than 9.8.
The following experim2ntal evidence serves to
illustrate the invention and to facilitate its understanding.
Granular detergent compositions were prepared in
a conventiQnal manner having the following formulae:
- 24 -
1 ()S03~
. _. _ . . .. . _ .... _ . . . ~ ........ _
I~REDIENT COMPOSITION IN % BY WE~GHT
... .....
AEXAMPLE I
.... .. _ _ ~, .. .. _
Ethylene oxide/propylene 2.6 9.7
oxide condensa-te of
trimethylol propane(l)
Monostearyl acid phosphate(2) 0.1 0.3
Sodium cumene sulfonate _ 10.0
Sodium tripolyphosphate4~7 _-
Sodium polymetaphosphate _ 2.0
1~ (Napo3)2l
Chlorinated trisodium 22.0
orthophosphate
Sodium carbonate _ 30.0
Sodium silicate solids17.0
Ratio: SiO2/Na2O = 2.8
Sodium silicate solids _ 20.0
Ratio: SiO2/Na2O = 2.0
Sodium sulfate 10.0 14.0
Sodium sulfite _ 14~0
Moisture and minor
ingredients --~ Balance to 100 ---
(1)&(23 "PLURADOT HA-433" Wyandotte
The above compositions were used for comparative
automatic dishwashing to evaluate the spotting, filming and
cleaning performance of the compositions of this invention
versus commercially available automatic dishwashing compos-
itions. The procedure outlined hereinafter was utilized for
the subjec-t purpose.
Spotting and Fllming
An automatic dishwashing machine was filled with
dishes. Four test glasses (Libbey Safe Edge 10 oz. tumblers
#553) were added in predetermined (the same for all tests)
- 25 -
~0503~)
positions in the upper rack. Prior to placement in the
machine, two of the test glasses were soiled with a thin
film of milk by coating them with refrigerated whole milk.
Thirty-five grams of a 4:1 ~e~ght mixture of homogenized
margarine and dry milk were placed in a 50 ml. beaker and
inverted in the top rack of the dishwasher. The required
amount of detergent product was then added to the dispenser
cup. The test consisted of 4 washer cycles whereby the
four glasses were graded at the end of the 4 cycles. ~he
levels of spotting and filming performance were appraised
with the aid of a 1-10 scale of photographic standards
(separate standards for spotting and filming) wherein 1
represents a completely unacceptable level of performance
and 10 represents a performance whereby residual spotting
and filming do not occur. The 8 grades (4 spotting; 4
filming) so obtained were averaged to determine average
spotting and filming grades.
Cleaning
~" x 1" glass slides were dipped in a food e~il
and aged by baking under the following conditions:
- gravy : 1 hour at 400F
- instant oatmeal : 30 minutes at 400F
- 26 -
310SV3~
Two slides of each soil were washed in a 1 liter TERGOTO-
METER* under the following conditions:
- washing time : 10 minutes
- washing temperature : 130F
- water hardness : 15 rJ~ S . grains/gallon
- agitation : 80 RPM
A tran~parent glass slide divided into 8 s~ual
sections is used as a template for estimating ~ soil re-
moval. The average of the 8 grades (for one slide) repre-
sents the cleaning grade.
The test results were as follows:
COMPOSITION SOIL CLEANING GRADE % SPOTTING FILMING
_ .. ._ _ , _ .
iA Gravy 87 8.2 7.9
EXAMPLE I Gravy 97 8.0 8.1
*Trademark
- 27 -
~OS~38~
The above results show the cleaning exce~lency
of a composition of this invention -- EXAMPLE I -- versus
what is obtained from a commercially available product --
COMPOSITION A --.
Substantially similar results can also be obtained
when the sodium cumene sulfonate is replaced with an equi-
valent amount of sodium toluene sulfonate, sodium xylene
sulfonate, sodium benzene sulfonate, sodium trimethylbenzene
sulfonate, sodium ethylmethylbenzene sulfonate, sodium ethyl-
benzene sulfonate, or mixtures thereof.
Substantially similar results are also obtained
when the nonionic surfactant of Example I is substituted
with a substantially identical alkoxylate containing in-
stead of the trimethylolpropane radical an alkylol sea~e~ed
from the group consisting of propylene glycol, glycerine,
pentaerythritol and ethylene diamine. Superior automatic
dishwashing performance comparable to Example I is also ob-
tained in replacing the trimethylolpropane alkoxylate by an
equivalent amount of the condensation product of one mole
of tallow alcohol and 9 moles of ethylene oxide.
An excellent performance is also obtained when
the monost~ary~ acid phosphate of Example I is replaced by
a silicone suds suppressant selected from the group consist-
ing of dimethyl-, diethyl-, dipropyl-, dibutyl-, methyl~
ethyl-, and phenylmethyl-polysiloxane and mixtures thereof
in an amount of 0~1%, 0.2~, 0.3%, 0.35%, 0.4% and 0.45% re=
spectively.
Results substantially comparable to those of Ex-
ample I can also be obtained when the suds suppressant is
represented by a microcrystalline wax having a melting
- 2~ -
~115V38~
point from 65C to 100C and which is selected from petro-
latum and oxidized petrolatum waxes; Fis~her-Tropsch and
Oxidized Fischer-Tropsch waxes; ozokerite; ceresin; montan
wax; beeswax; candelilla and carnauba wax.
Granular detergent compositions were prepared
having the following forlnulae:
. _ ~ .
INGREDIENT COMPOSITION IN % BY WEI~HT
.... _ ~ _ . .. , .... ,. _ =
~ EXAMPLE II
Ethylene oxide/propylene .
oxide condensate of tri-
methylol propane~l) 4.85
Monostearyl acid phosphate(2) 0.15 ~.~55
~Condensation product of
one-mole of tallow alcohol
and 9 moles of ethylene oxide _ ~4j0
Sodium cumene sulfonate . 6.0
Sodium dichlorocyanurate 4.0
Sodium polymetaphosphate 2.0 2.0
(~aP3)21
Sodium carbonate 30.0 30.0
Sodium silicate solids
Ratio: SiO2/Na2O = 2.0 20.0 20.0
Sodium sulfite _ 20.0
Sodium sulfate 39.0 19.0
(1) & (2) "PLURADOT HA-433" Wyando-tte
- 2~ -
05~
~hese compositions were tested for % cleaning grade
according to the procedure set forth hereinabove
(COMPOSITIO~.~ A, EXI~MPLE I~.
The test resul~s were as follows: -
.
., .
.
, . . . _ ,
. . .CLEA.~ING
- CO~IPOSITION SOIL GR~;)E ~
- . . . , A
B Gra~ 41 .
:Cnstan 37
_ _ . ..
EXAMPLE II Gravy . 83 .
. Instant 65
. Oatmeal .
. .
3 0
~i03~0
The markedly ennanced cleaning performance of
a com?osition a~cording to this inve~lt~on -- EXAMPLE II --
is shown by these tests. It is noteworthy that the
composition of EXAMPLE II provides spotting and filming
results which are at least as good as those obtained
from t~e use of commercially available chlorine-containing
al1tomatic dishwashing compositions.
.~ series of granular detergent compositions
were prepared in a conventional manner having the
following formulae.
~ 31 ~
... . . . . . . , , ., , " , . . .
~.05~3~ ~3 ~- f
r~ r - I I
. :- ~0_,'1 0 1,11 "~ 1~1 .
.
. . ~
'. . _ ~
~ ~0 1 1 ~ M~ ~
_ ~
E~ ~ ~ lo~ ',1 1 1,
. ~q ~ a~ o _~ ~ o N O Ct~
~ X .' _, .
.' ~ ~ o1~
. O 3~ _ ''_,__ _ , ; . I
H I~ ~ ~ I I I I .
S~l o~ O ~ ~ ~
. . ~ . ' .
. ~ _ ' . ~
. ~ C1~0 1 ~1 ~ I ~ I ~ I I I
_ ~
O CT~ O O O C~ O
__ ,~ __ ~
~ - ~ 3:
x ~ _
~ .C '~ ~r
. . O, s :S o O 11 . O il 0 ~a h O
. ~ G) P.Z .C C
0 ~ o ~ z ~ z~3 ~ ~ a~ h ~ ~
~ O a ~ 0 ~ -
X ~ ~ E ~ _
z ~ a O ~ _
5:~ ~ td 3 U Ul u~V t~. 0 U) t~ ~I
~il C. C. ~ 6.0 F~ 3 ~
~1~ P. O G~ O O
C o O O O ~0 ' D~ ; o ra ~0 ~ O _
,,, , ~ ~ I;
.. .. -- ~ . . .. . . . . . . . . . , ~
`~`\ ( ( ~
~L0~38q~
The above compositions -- C, I), ~, F, E ~ ~PLES III,
. IV, ~, VI -- were tested for spotting, filming and % cleaning
grade according to the tecnnique described hereinbefore
(COMPOSITION A, EXAMPLE I).
The test results were as ~ollows.
CO~POSITION SOIL CLEANING SPOTTING E'II.. ~ING¦
.
C Gravy 6 5 8 o l 7 . 9
Instant
.- . Oatmeal 7
. _ . .
Gravy 71 8 . 1 7 . 7
D I~stant 16
Oatmeal
. . Gravy .97 8.0 8.1
EXAMPLE III I~stant .
. Oatmeal 33
. __
Gravy ~7 8.1 8.1
EXAMPLE IV Instant 20 .
. Gravy ~9 7.7 8.0 .
EX~PLE V I nstant 27
. Oatmeal _
Gravy 78 8.2 i.9
E
Instant 14
Oatmeal _ _
F Gravy 81 B . 1 8 .1
Instant
_ Oatmeal 12 _
Gravy 91 7.7 8.0
EXAMPLE VI Ins tan t
_. Oat~eal 27
_ ~3 _
.. ~
~05~3~80
The above testing data reveals that the composi-
tions of this invention ~- EX~MPLES II~, IV, V and VI --
effectively provide superior cleaning performance versus
what is obtainable from compositions falling outside of
the scope of t~e claims of this invention.
.
34