Note: Descriptions are shown in the official language in which they were submitted.
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IR4677A PATENT
~' . .
NONAQUEOUS LIQUID AUTOMATIC DISI1WASHER DETERG~NT
COMPOSITION CONTAINING A DUAL BLEACH SYSTEM
FIELD OF THE INVENTION
.. .. ____
The present invention relates to a nonaqueous liquld automatic
dishwasher detergent composition having improved cleaning performance
against difficult to remove soils. The present invention i8 more particularly
directed to a stable nonaqueous liquid composition containing a dual bleach
system for use in an automatic dishwasher to clean dishware, glassware,
cookware and the like.
The dishwashing compositions are con~centrated and comprise an organic
carrier liquid, a surfactant and a stable suspens~on of a builder ~alt. The
detergent compositions of the present invention are stable in storage and
are readily pourable.
The present invention relates to an improved nonaqueous liquid dual
bleach composition and to a method of making and using the composition.
BRIEF DESCRIPTION OF THE INVENTION
. ~
The present invention is directed to a nonaqueous liquid automatic
dishwasher detergent composition having improved clsaning performance for
proteinaceous and carbohydrute soils. The liquid detergent composition
contains a chlorine bleach source and a bromide source. The detergent
composition more particularly contains a source of hypochlorite ion and a
25 source of bromide ion.
,~
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When the detergent composition iæ added to a wash bath a portion of
the hypochlorite ion reacts in situ with the bromide ion to form hypobromite
ion which is a powerful oxidizing agent.
The newly formed hypobromite ion i8 an effective agent for cleaning
S carbohydrate soils and the remaining unreac-ted hypochlorite ion is an
effective agent for cleaning proteinaceous soils.
The present invention specifically relates to liquid automatic
dishwashing detergent concentrate cornpositlons hnving Improved cleaning
l performance against proteinaceous and starchy carbohydrate solls on
¦ dishware, glassware, cookware and the lilse, particularly cooked on and
baked on soils.
The nonaqueous liquid compositions are stable in storage, do not
settle, are pourable and are readily dispersed in water.
l PRIOR ART
Commercially available household-machine dishwasher detergent~
provided in powder or liquid form have the disadvantage of not being
effective in cleaning both proteinaceous and starchy carbohydrate soils.
The cooked on and baked on proteinaceous and starchy carbohydrate soils
are particularly hard to remove. Though some detergent compositions have
been found to be effec$ive in removing proteinaceous 90ils and others have
been found effective in removing starchy carbohydrate soils, none have
been found effective in removing both proteinaceous and starchy
carbohydrate soils from dishware, glassware, cookware and the like.
~or effective use, it is generally recommended that the automatic
dishwashing detergent, hereinafter also designated ADD, contain (1) sodium
tripolyphosphate (NaTPP) to soften or tie up hard-water minerals and to
emulsify and/or peptize soil; (2) sodium silicate to supply the alkalinity
necessary for effective detergency and to provide protection for di~hware,
such as fine china and protection against machine corrosion; ( 3 ) sodium
carbonate, generally considered to be optional, to enhance alkalinity; (4) a
~ 2 :3 2 '~
chlorine-releasing agent to aid in cleaning (5) a surfactant and (6) a
defoamer to reduce foam, thereby enhancing machine efficiency. See, for
example, SD~ Detergents in Depth, "Formulations l~spects Of Machine
Dishwashing," Thomas Oberle (1974). Cleansers approximatin~ to the
afore-described compositions are mostly liquids or powders. Generally,
such compositions omit hypochlorite bleach, since it tends to react with
other chemically active ingredients, particularly surfactant, thereby
impairing its effectiveness.
The most difficult food soils to remove from dishware, cookware and
utensils are proteinaceous and starchy carbohydrate soils. The
proteinaceous 90ils can be in the form of baked on or cooked on milk, meats
and egg soils. The starchy carbohydrate soils can be in the form of baked
on or cooked on starchy carbohydrates such as pasta, oatmeal, porridge,
bread, cake and the like.
These two types of food soils are very tenaciously bound to the
dishware, cookware and utensil substrates and are very difficult to clean
without scrubbing.
Proteinaceous materials, for example, egg protein can be removed by
appropriate concentrations of, Ior example, sodium hypochlorite bleach.
llowever, dishwasher detergent compositions containing hypochlorite ion
perform poorly on starchy carbohydrate soils.
The hypobromite iOII iS a strong oxidizing agent, but i8 SO reactive
that it is chemically unstable in aqueous detergent compositions. Bromide
ion when contacted with hypochlorite in an aqueous alkaline medium wash
2 5 bath reacts to form hypobromite . The hypobromite effectively degrades
starchy carbohydrates.
However, iE too much bromide iOII iS present in the wash bath, it will
substantially reduce the hypochlorite ion concen-tration and/or will
completely remove the hypochlorite from the wash bath and the
proteinaceous soils are not removed.
202 ~99
If an insufficient amount of ~romide ion is present the st~rchy
carbohydrate soils are not rernoved.
The problem to be solved was to formulate a nonaqueous liquid
dishwasher detergent composition that was stable in storage and was
effective in a wash bath in removing both proteinaceous and starchy
carbohydrate soils.
In the I)iez llSP 3, 519, 569 there i9 dlsclosed an abrasive scouring
cleaner containing as essential in gredients a water insoluble siliceous
abrasive rnaterial, a hypochlorite-chlorine liberating compound, a water
soluble detergent compound and an alkali metal bromide.
The Finck USP 4 ,102 ~ 799 discloses an alkaline automatic dishwasher
detergent composition which is essentially free of inorganic phosphates and
which consists essentially of a citrate compound, and one or more inorganic
builder salts such as silicates, carbonates and/or sulfate. The composition
can also contain one or more bleaching agenta which ar~ capable of
liberating hypochlorite chlorine and/or hypobromite bromine on contact with
aqueous media.
The ~artman European Patent Application l~o. 0 ,186, 234 discloses an
automatic dishwasher powder detergent compositi~n comprising a detergent
builder, a source of hypochlorite, a low-~udsing nonionic surfactant, an
anti-sudsing agent and an alkali metal or alkaline earth metal bromide.
The Laitem et al USP 4, 753, 748 discloses a nonaqueous liquid automatic
dishwashing detergent composition comprising a liquid nonionic surfactant
containing a stable or readily redispersible ~uspension of a polyphosphate
builder and/or citrate salt and an alkylene glycol mono alkyl ether anti-gel
agent .
ADVANTAGES OVER TIIE PRIOR ART
_
The nonaqueous liquid ~etergent compositions OI the present invention
overcome many of the pricr art problems. Because of the addition of a
3 0 small effecti re amount of a bromide to the compositions, which generates
~ 7.1~ i
hypobromite in the wash bath the composition can be used to remove both
proteinaceous and starchy carbohydrate soilæ from dlshware, glassware,
cookware and the like.
In accordance with the present invention a stable nonaqueous liquid
dishwashing detergent composition containing a balunced source of
hypochlorite ion and hypobromite ion is advantageou~ly provided such that
the composition efficiently and effectively cleans both protsinaceous and
starchy carbohydrate soils from dishware, glassware, cookware and utensils
in an automatic dishwashing machine.
The nonaqueous liquid automatic dishwashing detergent compositions of
the present invention have the advantages of being stable, nonsettling in
storage, and non-gelling in storage, and are readily dispersible in the
dishwashing machine. The liquid compositions of the present invention are
l easily pourable, easily measured and easily put into dishwashing machines
¦ and are readily soluble in the wash water in the dishwashing machines.
Further, because the dishwashing machines as built and marketed have
a built in volume space ln which the detergent is placed, the highly
concentrated nature of the liquid detergent concentrate composition of the
present invention allows placing in the clishwashing machine more active
liquid nonionic surfactant detergent and more dispersed pol~rphosphate and
other detergent buildersO
OBJECTS OF THE P~ESENT INVENTIVN
..
It is an object of the present invention to provide a nonas~ueous liquid
automatic dishwasher detergent composition that has improved cleaning
2 5 performance against dif~icult to remove proteinaceous and starchy
carbohydrate soils.
It is another object of the invention to provide a nonaqueous liquid
detergent concentrate composition which is stable in storage, does not
degrade or decompose, is easily pourable, is readily dispersible and is
readily soluble in the dishwashing water.
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~nothel object of the present invention i~ to prepare a nonaqueous
¦ autvmatic dishwasher detergent composi-tion which contains both a chlorine
bleach source and a bromide source.
I Another object of the present invention is to prepare a nonarlueous
liquid automatic dishwasher detergent composition which on addition to a
wash bath generates a balanced amount of hypochlorite ions and
hypobromite lons, which are strong oxidizing agen-ts and together are
effective in cleaning both proteinaceous and starchy carbohydrate soils.
A further object of the invention is to provide a method of washing
dishware, glassware, cookware and -the like in an automatic dishwashing
machine using a nonaqueous liquid dual ble~ch system tletergent composition
which is effective in removing both proteinaceous and starchy carbohydrate
soil6.
A still further object of the invention is to provide a method of
washing dishware, glassware9 cookware and the like in an automatic washing
machine using a nonaqueous liquid nonionic surfactant detergent composition
by which method both proteinaceous and starchy carbohydrate soils are
efficiently and effectively removed from dishware, glassware, cookware and
the like.
It is a further object of this invention to provida stable nonaqueous
liquid detergent dual bleach compositions, especially automatic dishwasher
detergent compositions, by incorporating in the compositions a source of
chlorine bleach and a small effective amount of bromide compound.
DETAILED DESCRIPTION OF THE INVENTI~N
... ~
These and other objects of the invention which will become more
readily understood from the following detailed description of the invention
and preferred embodiments thereof are achieved by incorporating in the
nonaqueous liquid detergent composition a source of chlorine bleach and a
small but effective amount of bromide as the dual bleach systern.
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l In accordance with the present invention there i9 provided a
¦ nonaqueous liquid automatic dishwasher detergent compositlon which
¦ includes, on a weight basi~;
I (a) 20 to 6096 carrier liquid;
¦ (b) 0.1 to 12% chlorine bleach stable, water dispersible organic
surfactant detergent active material;
(c) 20 to 60~6 organic or inorganic builder salt;
(cl) 5 to 30g~ sodium silicate;
I (e) chlorine bleach compound in an amount to provicle 0.5 to 10%
available chlorine;
(f~ 0,1 to 6.0% bromide compound;
( g) 0 to 25~ alkali metal carbonate; and
(h) 0 to 6~6 chlorine bleach stable foam depressant.
The mole ratio of the bromide to available chlorine is critical and i~
o, 04 to 0, 12 .
The present invention also provides a method for cleaning dishware,
glassware and cookware in an automatic dishwashing machine with an
aqueous wash bath containing an effective amount of the automatic
dishwasher detergent (ADD) nonaqueous liquid composition as described
above. Accvrding to this aspect of the invention, the ADD cornposition is
stable in stor~ge, is easily measured and can be readily poured into the
automatic dishwashing machine.
The invention will now be described in greater detail by way of
specific embodiments thereof.
In accordance with the present invention an improved automatic
dishwasher detergent composition is prepared by incorporating small
amounts of a bromide containing compound in a nonaqueous liquid
dishwasher composition containing an organic carrier liquid, a surfactant
and a source of hypochlorite ion. When the dishwasher detergent
composition is added to an aqueous wash bath the bromide reacts with a
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¦ portion of the hypochlorite and the bromide is converted to hypobromite, a
¦ strong oxidizing agent.
¦ The present invention is based upon the discovery -that substantially
¦ improved cleaning performance for both proteinaceous and starchy
¦ carbohydrate soils can be obtained by adding to a nonaqueous liquid
¦ detergent composition a source of hypochlorite and ~ small effective amountof a bromide compound which when the detergent composition is added to
the aqueous wash bath form a hypochlorlte and hypobromite dual bleach
system .
In accordance with an en)bodiment the present invention a nonaqueous
liquid automatic dishwashing detergent concentrate composition i8 prepared
by dispersing a polyphosphate builder in an organic carrier liquid. The
polyphosphate builder may be replaced in whole or in part by organic
detergent builders such as alkali metal citrates or tartrates.
In addition other ingredients can be added to the composition such as
anti-encrustation agents, anti-foam agents, optical brighteners, enzymes
and perfume.
Organic Carri r ~uids
The organic carrier liquids that can be used in accordance with the
2 0 present invention are the carrier liquids, diluents and solvents that are
conventionally used in Eormulatin~ dishwasher detergents compositions.
Suitable organic carrier liquids are propylene glycol, propylene carbonate,
polypropylene glycol M . W, 200, polypropylene glycol M . W . 300, methoxy
propylene glycol, Carbowax l\qPEG 350 (polyethylene glycol methyl ether),
from Union Carbide, triethanol amine, Butyl Carbitol, from DuPont Co,
Glyme (ethylene glycol dimethyl ether), Diglyme (diethylene glycol dimethyl
ether) .
There can also be used as organic carrier liquids the alkylene glycol
monoalkyl ethers. The alkylene glycol mono alkyl ethers are low molecular
weight amphiphilic compounds, particularly a mono-, di or tri lower (C2 to
., .
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C3) alkylene glycol mono lower (Cl to C5) alkyl ether. Suitable examples
of such additive amphiphilic compounds are ethylene glycol monoethyl ether
(C2H5-0-(CH2CH20H), diethylene glycol monobutyl ether
(C4Hg-O-(CH2CH20)2H) and dipropylene glycol monomethyl ether
(cH3-o-(~H2 t Ho)2H) .
CH3
The above discussed organic carrier liquids can be used alone or in
admixture in order to obtain a desired viscosity and stability of the product
l liquid .
The compositions of the present invention have good viscosity and
stability characteristics and remain stable and pourable at low temperatures.
¦ Surfactant Deter~ents
Nonionic Surfactant Deter~ents
I The liquid nonionic surfactant detergents that can be used in the
practice of the present are preferably the low foam surfactants.
A preferred class of the nonionic detergent employed is the pvly-lower
alkoxylated higher alkanol wherein the alkanol is of 9 to 18 carbon atoms
and wherein the number of mols of lower alkylene oxide (of 2 OI' 3 carbon
atoms) is from 3 to 12, Of such materials it is preferred to employ those
wherein the higher alkanol i~ a higher fatty alcohol of 9 to 11 or 12 to 15
carbon atoms and which contain from 5 to 8 or 5 to ~ lower alkoxy groups
per mol. Exemplary of such compounds are those wherein the alkanol is of
12 to 15 carbon atoms and which contain about 7 ethylene oxide groups per
mol .
Useful nonionics are represented by the low foam Plurafac series from
BASE Chemical Company which are the reaction product of a higher linear
alcohol and a mixture of ethylene and propylene oxides, containing a mixed
chain of ethylene oxide and propylene oxide, terminated by a hydroxyl
group. Examples include a C13-C15 fatty alcohol condensed with 6 moles
ethylene oxide and 3 moles propylene oxide, a C13-C15 fatty alcohol
conclensed with 7 moles propylene oxide and 4 moles ethylene oxide and a
,
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¦ C13-C15 fatty alcohol condensed with 5 moles propylene oxide and 10 moles
¦ ethylene oxide,
Other useful surfactMnt6 are Neodol 25-7 and Neodol 25-6, 5, which
I products are made by Shell Chemic~l Company, Inc. The former is a
1 condensation product of a mixture of higher fatty alcohols averaging about
12 to 15 carbon atoms, with about 7 mols of ethylene oxicle and the latter i8
a corresponding mixture wherein the carbon atom content of the higher
fatty alcohol is 12 to 13 nnd the number of ethylene oxide groups present
averageæ about 6 . 5 . The higher alcohols are prlmary alkanols . Other
examples oî such detergents include Tergitol 15-S-7 and Tergitol 15-S-9
(registered trademarks), both of which are linear secondary alcohol
ethoxylates made by Union Carbide Corp, The former is mixed ethoxylation
product of 11 to 15 carbon atoms linear secondary alk~nol with seven mols
of ethylene oxide and the latter is a similar product but with nine mols of
ethylene oxide being reacted,
A preferred nonionic surfactant is available from Union Carbide
Corporation under the trademark Tergitol MDS-42, This nonionic surfactant
is a C12-C14 linear alcohol containing 55% by weight random distributed
oxyalkyl groups of which ~2~ are ethoxy and 58% propoxy groups. Anothsr
nonionic surfactant that can be used is Alfonic 18-57.
Other useful nonionic surfactants are the Poly-Tergent S-LF
surfactants available from Olin Corporation, These surfactant~ are low
foaming, biodegradable alkoxylated linear fatty alcohols, Surfactants of this
type are available under the tradenames Poly-Tergent S-LF 18,
Poly-Tergent S-305-LF, Poly-Tergent S-~05-LF and Poly-Tergent CS-1,
The use of the low foam nonionic surfactant, in the formulations is
important in avoiding cavitation problems during the wash cycle. The use
of the low foam nonionics is accordingly preferred.
Mixtures of two or more of the liquid surfactants can be used and in
some cases advantages can be obtalned by the use of such mixtures.
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The detergent active mater~ials used herein are selected to be stuble in
the presence of the other ingredients of the composition. In addition to the
above discussed nonionic surfactants, anionic surfactants can also be used.
Anionic Surfactants
The anionic surfactants that can be used are the linear or branched
alkali metal mono- and/or di- (C8 1~) alkyl diphenyl oxide mono and/or
disulphonates, commercially available for example as DOWFAX (Reglstered
Trademark) 3B-2 and DOW~X 2A-1,
I Other suitable surfactants irnclude the primary alkylsulphates,
¦ alkylsulphonates, alkylar~l-sulphates and sec. alkylsulphates. Examples
include sodium C10 18 alkylsulphates such as sodium dodecylsulphate and
sodium tallow alcoholsulphate; sodium C10 18 alkanesulphonates such as
sodium hexadecyl-l-sulphonate and sodium C12 18 alkylbenzenesulphonates
such as sodium dodecylbenzenesulphonates. The corresponding potassium
salts may also be employed.
The nonionic and anionic surfactants are used in amounts of 0. 5 to
12%, for example about 1.0 to 10%, preferably about 1.0 to 7.0%.
Chlorine Bleach Compounds
Hypochlorite generating compounds suitable for use In the compositions
of the present invention are those water soluble dry solid materials which
generate hypochlorite ion on contact with, or dissolution in, water.
Examples thereof are the dry, particulate heterocycllc N-chlorimides such as
trichlorocyanuric acid, dichlorocyanuric acid and salts thereof such as
sodium dichlorocyanurate and potassium dichlorocyanurate. ~he
corresponding dichloroisocyanuric and trichloroisocyanic acid salts can also
be used. Other N-chlorvimides may be used such as N-chlorosuccinimide,
N-chloromalonimide, N-chlorophthalimide and N-chloronaphthalimide.
Additional suitable N-chloroimides are the hydantoins such as
1, 3-dichloro-5, 5-dimethylhydantion;
N-monochloro-C, C-dimethylhydantoin;
Il
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¦ methylene-bis (N-chloro-C, C-dimethylhydantoin);
1 1, 3-dichloro-5-methyl-5-isobutylhydantoin;
; I 1, 3-dichloro-5-methyl-5-ethylhydantoin;
1, 3-dichloro-5, 5-diisobutylhydantoin;
1 1, 3-dichloro-5-methyl-5-n-amylhydantoin;
and the like. Other useful hypochlorite-liberating agents are
trichloromelamine and dry, particulate, water soluble anhydrous inorganic
salts such as calcium and lithium hyE~ochlorite. The hypochlorite liberating
~; agent may, if desired, be a stable, solid complex or hydrate such as sodium
p-toluene -sulfo-chloramine-trihydrate (choramine-T), sodium
benzene-sulfo-chloramine-dihydrate, calcium hypochlorite tetrahydrate, or
chlorinated trisodium phosphate containing 0. 5 to 4% available chlorine
produced by combining trisodium phosphate in its normal Na3P04:12H20 form
and an alkali metal hypochlorite (e.g., sodium hypochlorite).
In compositions in which the alkuli and alkaline earth metal
hypochlorites are used as the chlorine source, these compounds can be used
in the form of anhydrous dispersed solids in order to prevent deteriation of
the nonionic surfactants in the composition.
The preferred sources of hypochlorite are dichloro- and
trichloroisocyanurates and chloramine-T (p-Toluenesulfochloramine).
TypicaIly the chlorine-liberating agents are employed in a proportion of
about l to 18% by weight of the composition, and preferably about 1.0 to
15% and more preferably 2 to 12% Desirably the proportion thereof
employed will be ~uch as to yield a product which contains from about 0.5%
to about 10% available chlorine on a total weight basis, preferably 1 to 8 4
and more preferably 1 to 6.7% available chlorine.
The composition should contain sufficient chlorine bleach compound to
provide about O . 5 to 10 . 0% by weight of available chlorine, as determined,
for example, by acidification of the composition with 6ulfurio acid and
iodometric titration with sodium thiosulfate monitored by a potentiometer. A
.
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20~ D ~
composition containing about 0 . 9 to 18% by weight of sodium
dichloroisocyanurate dihydrate contains or provides about 0.5 to 10%
available chlorine. A composition containing about 1,6 to 10.72% by weight
calcium hypochlorite contains about l to 6,7% by we~ght available chlorins.
A composition containing about 1,8 to 12.0% by weight sodium
dichloroisocyanurate dihydrate contains about 1 to 6 . 796 by weight of
available chlorine and is especially preferred.
Bromide Compounds
The bromide source or compouncl used in the present invention can be
a solid water soluble bromide which preferably is of substantially neutral or
slightly alkaline nature, providing a ready source of bromide ions on
dissolution in water. It is preferred to employ alkali metal bromides such
as sodium bromide, sodium bromide dihydrate, lithium bromide, nnd
potassium bromide, although alkaline earth metal bromldes such as calcium
bromide and magnesium bromide may be employed in those instances in
which these water hardne~s-producing cations are not objectionable.
The bromide compound for example alkali metal bromides are used in
amounts of 0 .1 to 6 wt . %, preferably 0 . 2 to 4 . 0 wt . % and more preferably
0.3 to 3.0 wt.%.
Preferably the bromide is employed in an amount which is substantially
less than the molar equivalent of available chlorine present in the product, ..
e.g., the mole ratio of water soluble bromide to available chlorine is in the
range of 0.0~ to 0,12, preferably less than 0.10, for example 0.05 to 0.095,
and typically 0 . 05 to 0 . 090 .
A balanced detergent composition is obtained which contains a small
effective amount of the bromide to react with the hypochlorite to form a
sufficient amount of hypobromite to remove the starchy carbohydrate soil
and to leave a sufficient amount of hypochlorite ion in the wash bath to
remove the proteinaceous soil.
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Tllus, the weight percent availabl~3 chlorine and the mole ratio of
bromide ion to available chlorine ion are critical features of the present
invention .
B uilder S alts
. . __
Generally, liquid ADD effectiveness is directly related to (a) available
chlorine levels; (b) alkalinity; (c~ solubility in washing medium; and (d)
foam inhibition. It is preferred that the pH of the aqueous wash buth after
addition of the liquid ADD composition be at least about 9.5, more
preferably from about lO . 5 to 13, 5 and most preferably at least about 11. 5 .The amount of alkali metal silicate added and the amount of alkali metal
TPP added can be used to obtain the desired alkalinity in the wash bath.
The sodium carbonate can be added to act as a buffer to maintain the
desired pll level. The sodium carbonate can be added in an amount of 0 to
25 wt.%, preferably 5 to 20 wt.g6 and typically about 5 to 15 wt.~ of the
¦ detergent composition.
The compositlons of the present invention can contain inorganic builder
salts such as NaTPP or organic builder salts such as the alkali metal salts
of polycarboxylic acids.
A preferred inorganic builder salt is an alkali metal polyphosphate
such as sodium tripolyphosphate (TPP). In place of all or part of the
alkali metal polyphosphate one or more other detergent builder salts can be
used. Suitable other builder salts are alkali metal borates, phosphates and
bicarbonates. Specific examples of such builders are sodium tetIaborate,
sodium pyrophosphate, potassium pyrophosphate, sodium bicarbonate,
sodium hexametaphosphate, sodium sesquicarbonate, so~ium mono and
diorthophosphate, potassium bicarbonate and sodium or potassium ziolites.
The detergent builders, e.~. NaTPP may be employed in the
nonaqueous liquid ADD composition in a range of 20 to 60'6, preferably
about 15 to 55 wt.%, and more preferably about 20 to 45 wt.%, and should
preferably be free of heavy metal which tends to decompose or inactivate
14
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the chlorine bleach compounds. The NaTPP rnay be anhydrous or hydrated,
including the stable hexahydrate with a d~egree of hydration of 6
corIesponding to about 18~, by weight of water or more.
The NaTPP may be replaced in whole or in part by organic builder
salts. Since the compositions of this invention are generally highly
concentrated, and, therefore, may be used at relatively low dosage~, it is
desirable to supplement any phosphate builder (swch as sodium
tripolyphosphate) with an auxiliary builder such as an alkali metal
polycarboxylic acid. Suitable alkali metal polycarboxylic acid~ are alkali
metal s~lts of citric and tartaric acid, e. g. monosodium and disodium citrate
(anhydrous). The sodium salts of citric and tartaric acids are preferred.
Foam Inhibitors
Fo~m inhibition is important to increase dishwasher machine efficiency
and minimize destabilizing effects which might occur due to the presence OI
excess foam wlthin the washer during use. Foam may be sufficiently
reduced by suitable selection of the type and/or amount of detergent active
material, the main foam-producing component. The degree of Loam is also
somewhat dependent on the hardness of the wash water in the machine
whereby suitable adju~tment of the proportions of NaTPP which has a water
softening effect may aid in providing the desired degree of foam inhibition.
However, it is generally preferred to include a chlorine bleach stable foam
depressant or inhibitor. Particularly effective are the alkyl phosphonic acid
esters of the formula
1l .~
HO--P--R
OR
25available, for example, iErom BASF-Wyandotts (PCUK-PA~), and espscially
~ the elkyl aci hoephete estere of the formule
. .
, , , .. . .. ~.. .
~ 3 ~
HO - P--OR
OR
available, for example, from Hooker (SAR3 and Knapsack (LPKN-158), in
which one or both R groups in each type of ester may represent
independently a Cl2_20 alkyl group. Mixtures of the two types, or any
other chlorine bleach stable types, or mixtures of mono- and di-esters of
the sflme type, may be employed. Especially preferred is a mixture of
mono- and di-Clfi 18 alkyl acid phosphate esters such as
monostearyl/distearyl acid phosphates 1,2/1 (Knapsack). When employed,
l proportions of 0 . 01 to 5 wt . ~, preferably 0 .1 to 5 wt . %, especially about
¦ 0 1 to 0.5 wt.96, of foam depressant in the composition is typical, the
weight ratio of detergent active component to foam depressant generally
ranging from about 10:1 to 1:1 and preferably about 4:1 to 1:1. Other
defoamers which may be used include, for example, the known silicones
such as Dow Corning 1400 and 1500, which are polysiloxanes mixed with
dispersed silica.
The alkali metal silicates, e.g. sodium silicate, which provide alkalinity
and protection of hard surfaces, such as fine china, are employed in an
amount ranging from about 5 to 30 wt.%, preferably about 8 to 25 wt.%, and
more preferably about 10 to 20 wt . %, in the composition . The sodium
silicate also protects the washing machine from corrosion. The ~odium
silicate can have a Na20:Si02 ratio of 1.6/1 to 1/3.2. The sodium silicate
can be added in the form of nonaqueous dispersions or dry powders,
preferably having an Na2O:SiO2 ratio of from 1/1 to 1/2.8, for example, 1/1
to 1/2 4, Potaæsium silicates of the same ratios can al90 be used. The
2 5 preferred alkali metal silicates are sodium disilicate and sodium metasilicate .
Most of the other components of the composition, for example, sodium
hypochloxite and foam depressant can be added to the nonuqueous liquid
18
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composition in the form of dry powders or nonaqueous dispersions or
solutions .
Various conventional ingredient~ may be included in these compositions
in small amount6, generally less than about 4 wt.~, such as perfume,
hydrotropic agentæ such as the sodium benzene, toluene, xylene and cumene
sulphonates, preservatives, clyestuffs and pigments and the like, all of
course being stable to chlorine bleach compound and high alkalinity
(properties of many of the components). Especially preferred for coloring
are the chlorinated phthalocyanines and polysulphides of aluminosilicate
which provide, respectively, pleasing green and blue tints.
The composition may also include conventional organic or inorganic
thickening agents in amounts sufficierlt to obtain a product con~istency of a
cream or a paste.
The thickening agents, i.e. thickeners or suspending agents which
provide thickening properties, are known in the art and may be organic or
inorganic, water soluble or insoluble, dispersible or colloid-forming, and
monomeric or polymeric, and should of cour~e be stable in these
compositions, e.g. stable to alkalinity and bleach compounds, such as
sodium hypochlorite. The prsferred thickeners generally comprise the
inorganic, colloid-forming clays OI smectite and/or attapulgite types. These
materials are generally used in amounts of about 1.5 to 10, preferably 2 to
5 wt%, to confer the desired thickening properties to the formulation.
Smectite clays include montmorillonite (bentonite), hectorite,
attapulgite, smectite, saponite, and the like. Montmorillonite clays are
preferred and are available under tradenames such as Thixogel (Regi~tered
Trademark) No . 1 and Gelwhite (Registered Trademark) GP , H , etc ., from
Georgia Kaolin Company; and ECCA(3UM (Registered Trademark3 GP, H,
etc., from Georgia Kaolin Company; and ECCAGUM (Regi~tered Trademark3
GP, H, etc., from Luthern Clay Products. Attapulgite clay~ include the
materials commercially available under the tradename Attagel (Registered
`
. . : .
~ ,,~
Trademark), i.e. Attagel 40, Attagel 50 and Attagel 150 from Engelhard
Minerals and Chemicals Corporation. Mixtures of ~;mectite and attnpulgite
types in weight ratios of 4:1 to 1:5 are also useful. Thickening or
suspending agents of the foregoing types are well known in the art, being
described, for example, in llSP 3,985,~68, which i8 incorporated herein by
reference there-to.
The conventionally used organlc polymeric thickenlng agents, such as
the polyacrylates, e.g. powdered polyacrylates having a molecular weight of
1,000-20,000 can be used. Suitable polyacrylates, e.g. sodium, are
¦ Alcosperse 130D, M W 15,000, avnilable from Alco Chem. Co. Alcosperse
149D, MW 2000, available from Alco Chem. Co, and Alcrysol 45N, MW 4500,
available from Rhom & Haas Co. The polyacrylates are ~tlisclosed more fully
in copending application Serial No. 323,126, filed March 10, 1989, whicil is
encorporated herein by reference thereto.
The nonaqueous liquid ADD compositions of this invention are readily
employed in known manner for washing dishes, glasses, cups, cookware,
eating utensils and the like in an automatic dishwasher, provided with a
suitable detergent dispenser, in an aqueous wash bath containing an
effective amount of the composition.
In a preferred embodiment of the invention an automatic dishwashing
detergent concentrate compositlon is formulated using the below named
ingredie
`-' 2 ~
Component Weight Percent
Organlc Carrier Liquid 30-45
Surfactant Detergent 3-7 . 0
Sodium Tripolyphosphate 20-45
Sodium Carbonate 5-15
Sodium Silicate 10-20
Sodium Bromide 1-3, 0
Sodium Dichloroisocyanurate 3-~ . 7
(Available Chlorine)
l Sodium Polyacrylate (MW 15, 000) ~-10
Pigment 0.5 to 2.5
The commercially available liquid detergent composition dose per wash
is 80 grams, whereas the concentrate liquid detergent composition dose per
wash of the present invention is 40 grams.
The nonaqueous liquid dishwasher detergent compositions of the
lS present invention can contain conventional dishwashing detergent
composition additives. The formulations can be prepared with commercially
available powder detergent builders, chlorine bleach source compounds and
bromide compounds.
The formulations can be prepared using the conventional blending and
mixing procedures used for the preparation of liquid detergent compositions
as briefly described below.
Method Of Preparation of Liquid Cornpos tion
The compositions of the present invention can be prepared in two
stages. In the first stage powdered silicate and low molecular weight
2 5 polyacrylate powder are premilled using a ceramic ball mill ~ The premilled
materials are then mixed using a standard rotary mixer. This mixed
material is then transferred to an attritor and milled for 30 minutes at 500
rpm using 1/~ ineh stealite grinding media.
" ; . : ",
` 2 0 ~ '
In the second stage Butylcarbitol (organic carrier liquid) and Neodol
25-6.5 (nonionic surfactant) are mixed, and the defoamer and phosphate
builder salts are added. The premilled silicate and polyacrylate are then
added to the Butylcarbitol and nonionic surfactant mixture followed by the
addition of sodium carbonate, chlorine bleach, bromide and the remaining
ingredients. After mixing the liquids solids mixture is vigorously stirred to
obtain a stable dispersion of the solids in the or~anic carrier liquid.
One or more of the ingredients can be omitted or additional ingredients
I such as perfumes and anti-foam agents can be added to the composition.
10 1 The term nonaqueous liquid compositions as used herein is intended to
include compositions containing 0-lS~ water, typically 2-12% and more
typically 4-8% water. The water can be present in the form of hydrated
compounds, i.e. bound water, for example, sodium tripolyphosphate
hexahydrate, hydrated sodium carbonate, hydrated sodium sulfate and
dichloroisocyanurate dihydrate and/or in the form of moisture, i.e. unbound
water. It is preferred, however, that the composition contain less than 1%
moisture as unbound water.
In the compositions containing an alkali metal hypochlorite and a
nonionic surfactant, it is particularly lmportant that the compositions
contain less than 1% unbound water, or substantially 0% unbound water,
inorder to prevent deterioration of the nonlonic surfactant
The invention may be put into practice in various ways and a number
of specific embodiments will be described to illustrate the invention with
reference to the accompanying examples.
All amounts and proportions referred to herein are percent by weight
of the composition unless otherwise indicated.
The pre t invention ie eurther ilIustrsted by the following examples.
. : . , ., . ~ : ,
- 2U~ 99 '~
l Example 1
I
In accordance with the present invention nonaqueous liquid automatic
dishwasher detergent compositions are formulated using the below named
l ingredients in the amounts indicated.
S Concentrated Comparison
Ingredient Composition Wt . % C~ _ion Wt . %
, 1
Organic Carrier hiquid~lJ 31.14 34.9
Surfactant( ) 6 . 0 6 . 0
Sodium Tripolyphosphate (Anhydrous) 23,0 26.0
Sodium Meta-Silicate 14, 5 14, 5
Sodium Acrylate ( 3 ) 6, 0
Sodium Carbonate 12, 0 12 . 0
Sodium Dichloroisocyanurate( ) 5 . 36 5, 36
Sodium Bromide 0. 80
Dow 1500 Antifoam(5) 1.2 1,2
100 100
(1) Methoxypolyethylene Glycol, Carbowax DqPEG 350, Union Carbide.
(2) Tergital MDS-42, from Union Carbide, which i8 a nonionic surfactant
and is a C12-C14 linear alcohol containing 5596 by weight random
distributed oxyalkyl groups of which 42% are ethoxy and 58% propoxy
groups .
(3) Alcosperse 130 D, MW 15,000.
(4) ACl 56, from Monsanto Corporation, available chlorine in composition is
3 . 0% by weight .
(5) Mixture of silica powder and dimethyl polysiloxan.
The mole ratio of bromide to available chlorine in the above invention
composition i9 about 0 . 09.
Multi-soil cleaning tests are run at stress conditions of 120F wash
cycle temperature and 3û0 ppm hard water in a low performance dishwasher.
This is don o show difierenc~s between the products which sre less
:1
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: , .
`~ 3 9 ~;
apparent in normal use conditions Wit}l tap water, e.g. 100 ppm hard water,
and 140F wash temperature.
Egg soil i9 prepared by mixing egg yolk with an equal arnount of 2,5N
calcium chloride solution . O .4 grams of this mlxture is applied to the
S usable surface OI 7.5 inch china plates in a thin film . The plates are aged
in 50~ relative humidity overnight.
Oatmeal 90il iS preparecl by boiling 24 grams of Quaker Oates in 400 ml
of tap water for ten minutes . 3 grams of $his mixture is spread onto a 7.5
inch china plate. The plates are aged for 2 hours at 80C. They are then
storecl overnight at room temperature. Two plates are used per wash.
The plates are always placed in the same poæition in the dishwasher.
The nonaqueous liquid detergent products to be tested are added at
the beginning of the wash cycle. 40 gm of product is used for each test.
All plates are scored by measuring the percent area cleaned.
The multi-soil cleaning results are reported below:
Percent Soil Removal
Product ~ Starch
Invention Composition 50~ 90%
Comparison Composition 45% 40%
The above compositions are also tested cleaning glass tumblers.
The ASTM Method D355G-79 for the deposition on glassware during
mechanical dishwashing i9 used to evaluate the buildup of spots and film on
glassware. 40 gm of comparison liquid ADD and 40 gm of the invention
liquid detergent is used in each test. All testing reported is done in
Kenmore Model 587.1548580 and/or model 587.1546580 Automatic Dishwasher.
The water wash temperature is 120F and the water has 300 ppm hardness
and the results are the average of four washes using 6 to 10 glass tumblers
per wash.
The information obtained is reported below.
¦ Spot Film
¦ Invention Composition 1 ~ 1. 5
Comparison Composition 1. 3 2 . 5
I
l The film/spot scale used in the above evaluation is given below.
SPOT/FILM SCALE
Spot On Glasses
1 = no spots
2 = 1-2 spots
3 = 25 percent of glass covered with spots
4 = 50 percent o glass covered with spots
5 = 100 percent of glass covered with spots
Film On Glasses
l = best - no film
2 = film slightly apparent
3 = increase in noticeable film
4 = filming significant
5 = filming becoming excessive
6 = filming highly excessive
23
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Exam~e 2
l Following the teachings of the invention a nonaqueous liquid automatic
¦ dishwasher detergent composition is formulated using the below named
, ingredients in the amounts indicated.
a Welght Pereent
Organic Carrier Liquid( ) 32-38
Sodium Tripolyphosphate( ) 23, 4
Nonionie Surfaetant( ) 3.0
Sodium Carbonate 12
Sodium Silicate 14, 0
Sodium Aerylate ( 4 ) ~ .
Sodium Bromide(5) 0-6
Sodium Dichloroisocyanurate(6) 3.6
( 1 ) Butylcarbitol .
(2) STPP (anhydrous).
(3) Tergitol MDS-42.
(4) Alcosperse 130 D, MW 15,000.
(5) Sodium bromide concentration is varied from 0 (eontrol) to 8.0 wt.~6 for
comparison purposes. The organic carrier liquid is adjusted to 100%.
There are four formulations prepared containing 0 (control), 0, 6, 1. 0
and 2 . 0 wt . % sodium bromide .
(6) Available ehlorine in composition is 2.0% by weight.
The formulations and soiled dishware are prepared following the
procedure of Example 1 except that porridge is substituted for the oatmeal.
40 gm of product is used for each test. The multi-soil cleaning test i8
carried out following the procedure of Example 1, but using GE Model GSD
1200G Automatic Dishwasher at 120F wash temperature and tap water with
about 110 ppm water hardness.
The results that are obtained are reported in the below table.
,,, ~ i
ADD Formulation
Sodium Bromide Percent Percent Mole Ratio
Concentration Porridge Egg Bromide To
Test ~ Removal RemovalAvailable hlorine
A 0 20 90
B 0.6 80 75 0,10
C 1 . 0 100 60 0 . 17
D 2 . 0 100 30 0 . 34
Theabove informationillustrQtes the effect on the removal of .:
proteineous soil and starch carbohydrate ~oil by varying the mole ratio of
bromide to available chlorine in the formulation.
; . . .
~0~ ~9~ ~
Example 3
In accordance with the pr~sent invention a nonaqueous liquid automatic
. dishwasher detergent composition is formulated using the below named
ingredients in the amounts indicated.
Component Wei~ht Percent
Organic Carrier Liquid 40. 2
Nonionic Surfactant 3 ~
Sodium Tripolyphosphate 30. 0
Sodium Carbonate 8, 0
Sodium Silicate (1:1) 14,0
Sodium Bromide . 30
Sodium l~ichloroisocyanurate(l) 2,5
Clay Thickening Agent 2,0
100.0
(1) 1.4% by weight available chlorine.
The mole ratio of bromide to available chlorine is 0.07.
About 60 gm of the above formulation is used in an automatic
dishwasher machine to clean dishes containing baked on proteinaceous egg
soil and baked on starchy carbohydrate pasta soil.
The dishes after a normal wash cycle are removed from the dishwasher
and are found to be substantially reduced in both the proteinaceous egg
soil and the starchy carbohydrate pasta soil.
2~
2U2'71~
Following the teachings of the present invention a nonaqueous liquid
automatic dishwasher detergent composition i8 formulated using the below
named ingredients in the amounts indicated.
Ingredient
Organic Carrier Liquid 36 . 4
Nonionic Surfactant 4 .
Sodium Tripolyphosphate 15,0
Sodium Citrate 15 ~ O
Sodium Carbonate 8, O
Sodium Silicate (1:2,4) 1~
Sodium Bromide 0. 60
Sodium Dichloroisocyanurate( ) 5 .
100.00
(l) 2.8% by weight available chlorine.
The mole ratio of bromlde to available chlorine is 0.07.
About 60 gm of the above concentrated liquid formulation is used in an
automatic dishwasher machine to clean dishes containing balced on
proteinaceous egg soil and baked on starchy carbohydrate pasta soil.
The dishes after a norm~1 wash cycle are removed from the dishwasher
and are found to be substantially reduced in both the proteinaceous egg
soil and the starchy carbohydrate pasta soil.
The above illustrative Examples show that the dual bleach automatic
dishwashing powder detergent compositions of the present invention provide
improved removal of proteinaceous soil9 and starchy carbohydrate soils from
dishware, glassware and the like.
The invention is no-t to be limited by the above disclosure and
examples which are given as illustrations only. The invention i~ to be
interpreted in accordance with the below claims.
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