Note: Descriptions are shown in the official language in which they were submitted.
~ ~ - ~ 2~031289
IR4 4 22 l
¦ AUTOMATIC DIS~IWASHER POWDER DETE~GENT COMPOSITION
RELATED APPLICATIONS
- - This application is a continuation-in-part of applicants' copending
l applications Serial No. 323 ,138 filed March 13, 1989, Serial No. 323,126,
¦ ffled March 10, 1989, Serial No. 323,139, filed March 13, 1989 and Serial
No, 323,137, filed Murch 13, 1989 all of which are directed to aqueous
automatic dishwasher detergent compositions containing an anti-fflming agent
or an anti-filming and anti-spotting agent.
¦ FIELD OF THE INVENTION
¦ The present invention relates to an automatic dishwasher detergent
¦ composition having improved snti-filming properties. The present invention
¦ is particularly directed to a stable dry powder detergent composition
¦ containing an anti-filming agent for use in an automatic dishwasher to clean
¦ dishware, glassware and the like.
¦ The present invention more particularly relates to a powder automatic
¦ dishwsshing detergent composition with improved anti-filming and
¦ anti-spotting properties and to a method of using the detergent composition
to- clean dishware, glassware, china and the like. The dishwashing
¦ composition contains an anti-filming agent, or an anti-fflming agent and poly
¦ scrylic acid polymer or salt as anti-filming and anti-spotting agents,
inorganic builder s~lts, chlorine bleach and bleach stable detergent.
The detergent dishwashing composition of t~e present invention
reduced filming and/or spotting on dishware, glassware, china and the like,
particularly in hard water at low temperature.
2 ~ More specifically, the invention relates to the use of a nonabrasive
amount of small substantially water insoluble particles, e. g. silica, as an
anti-fiIming agent and polyacrylic acid or s~lt polymer as an anti-spotting
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agent in powder dishwashing detergent compositions to reduce filmlng
andlor spotting.
The detergent compositions do not require an added rinse aid, are
stable in storage and are readily dispersible in wash bath.
The present invention specifically relates to powder automatic
dishwashing detergent compositions having improved anti-filming and
anti-spotting properties, which are readily dispersible in the washing
medium to provide effective cleaning of dishware, glassware, china and the
lilce .
The present invention also relates to an improved powder composition
and to a method of using the composition.
Bl~IEF DESCI~IPTION OI~ THE INVENTION
The present invention is directed to a powder automatic dishwasher
detergent composition having improved anti-filming and/or anti-spotting
properties for cleaning of dishware, glassware, china and the like. The
detergent composition contains as an essential ingredient a nonabrasive
amount of small substantially water insoluble solid particles as an
anti-filming agent. The compositions can additionally contain a polyacrylic
acid polymer or salt as an anti-spotting agent.
The present invention specifically relates to powder automatic
dishwashing detergent powder compositions having improved anti-filming
and/or anti-spotting properties for cleaning of dishware, glassware, china
and the like.
The powder compositions are dry, free flowing and readily dispersed
in the wash bath.
PRIOR ART
Commercially available household-machine dishwasher detergents
provided in powder or liquid form have many disadvantages.
Commercially available powder detergents have the disadvantage8 of
non-uniform composition; costly operations necessary in their manufacture;
tendency to cake in storage at high humidities, resulting in the formation of
'
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lumps which are difficult to disperse; dustiness, a source of particular
irrit~tion to users who suffer allergies; and tendency to cake in the
dishwasher machine dispenser. Liquid forms of dishwashing compositions,
however, generally cannot be used in automatic dishwashers due to high
foam levels and unaccept~bly low viscosities.
In addition, the commercially available formulated powder detergents
frequently require a separate step of hand towel wiping and drying of the
dishware, glassware, china and the lilce to avoid leaving undesirable traces
or film. The use of liquid detergent compositions present other problems.
The builder s~lts settle in storage and are not readily redispersed. The
compositions also frequently become thicker in storage and are not readily
pourable .
For 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 dishware,
such as fine china and protection against machine corrosion; (3) sodium
carbonate, generally considered to be optional, to enhance alkalinity; (4) a
chlorine-releasing agent to aid in cleaning; ~5) a surfactant and (6) a
f defoamer to reduce foam, thereby enhancing machine emciency. See, for
example, SDA Detergents in Depth, "Formulations Aspects Of Machine
Dishwashing," Thomas Oberle (1~79), Cleansers approximating to the
afore-described compositions are mostly liquids or powders. Generally,
such composition9 omit hypochlorite bleach, since it tends to react with
other chemically active ingredients, particularly surfactant, thereby
impairing its effectiveness.
Th~ls, U . S . Patent No . 3, 985, 668 describe~ abrasive scouring cleaners
of gel-like consistency containing (~) suspending agent, preferably the
Smectite and attapulgite type.~ of clay; (2) abrasive, e.g. silica sand or
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¦ perlite; and (3) filler comprising light density powdered polymers,
expanded perlite and the like. The perlite has a bouyancy and thus
stabilizing effect on the composition in addition to serving as a bulking
¦ agent, thereby replacing water otherwise available for undesired
¦ supernatant layer formation due to leaking and phase destabilization. The
¦ foregoing are the essential ingredients. Optional ingredients include
hypochlorite bleach, bleach stable surfactnnt and buffer, e. g. silicates,
¦ carbonates, and monophosphates. Builders, such as NaTPP, can be
¦ included as further optional ingredients to supply or supplement building
¦ function not provided by the buffer, the amount of such builder not
¦ exceeding 5% of the total composition, according to the patent. Maintenance
¦ of the desired (greater than) pH 10 levels is achieved by the buffer/builder
¦ components. High pH.is said to minimize decomposition of chlorine bleach
¦ and undesired interaction between surfactant and bleach. When present,
¦ NaTPP is limited to 596, as stated. Foam killer is not disclosed.
¦ U . S . Patent 9, 511, 487 dated April 16, 1985 describes a low-foaming
l detergent paste for dishwashers, The composition is based on a mixture of
¦ finely divided hydrated sodium metnsilicate, an active chlorine compound
¦ and a thickening agent which is a foliated silicate of the hectorite type.
¦ Small amount of nonionic tensides and alkali metal carbonates andlor
hydroxides may be used.
ADVANTAGES OVER THE PRIOR ART
The powder detergent compositions of the present invention overcome
many of the prior art problems associated with powder and liquid
2~ detergents. Because of the addition of a small effective amount of a silica
anti-filming agent or silica and polyacrylic acid polymer or salt anti-spotting
agent to the composition an added rinse aid is not required to obtain dry
sparkling clean dishes, glasses, cups and eating utensils.
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The powder dctergent composition has the additional ndvantages of
being stnbls in storage and readily redispersible in the dishwashing
machines. The powder compositions of the present invention are easily
pourable, easily measured and easily put into the dishwashing machines.
An additionnl and unexpected advantage of adding the silica
anti-filming agent to the detergent formulation is that the silica inhibits
brown stain formation in the dishwashing machine. The brown stain is
formed by the deposition in the dishwashing machine of iron and/or
manganese oxides. The brown stain formation is a particularly serious
problem in areas having hard water. The silica in the formulation acts on
the iron and/or manganese in the wash water to prevent their deposition in
the dishwashing machine as iron and/or manganese oxides.
The powder detergent compositions of the present invention are stable
in storage, are readily dispersed and, with the exception of the anti-film
agent, are easily soluble in the dishwashing machine.
OBJECTS OF THE PRESENT INVENTION
It is an object of the present invention to provide a powder automatic
dishwasher detergent composition that has improved anti-filming and/or
anti-spotting properties.
It is another object of the invention to provide a powder detergent
composition which is stable in storage, does not degrade or decompose, i8
readily dispersible and is easily soluble in the dishwashing w~ter.
A further object of the invention is to provide a method of washing
dishware, glassw~re, china and the like in an automatic dishwashing
machine using a powder detergent composition in which a separate rinse aid
is not added or needed.
A still further object of the invention is to provide a method of
washing dishware, glassware, china and the like in an automatic washing
machine using a powder detergent composition by which method the
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dishware, glassware, china and the like are machine dried with reduced
film, and spots.
It is a further object of this invention to provide stable dry powder
detergent compositions, especially automatic dishwasher detergent
S compositions, by incorporating in the composition a small effective amount of
a silica anti-filming agent or silica and polyacrylic acid polymer or salt as
anti-filming and anti-spotting agents.
DETAILED DESCRIPTION OF THE INVENTION
These and other objects of the invention which will become more
readily understood from the following detsiled description of the invention
and preferred embodiments thereof are achieved by incorporating in a
powder detergent composition a small but effective amount of a silica
anti-filming agent or silica anti-filming agent and polyacrylic acid polymer
or salt anti-spotting agent. More particularly, according to a preferred
and specific embodiment of the invention, there is provided a powder
automatic dishwasher detergent composition in which is incorporated from
about 0. 5 to 594 of a silica anti-filming agent or silica anti-filming agent and
1 to 15% of a water soluble polyacrylic acid polymer or salt anti-spotting
agent. The silica anti-filming agent has a particle size of about 0.1 to 10
microns. The water soluble polyacrylic acid or salt polymer has a molecular
weight of about 1000 to 100,000.
In accordance with the present invention there is provided a dry
powder automatic ~ishwasher detergent composition which includes, on a
weight basis;
(a) 20 to 70% organic or inorganic builder salt;
(b) S to 4096 sodium silicate;
(c) chlorine bleach compound in an amount to provide 0.5 to 8%
available chlorine;
(d) 0.5 to 5~ silica anti-filming agent;
(e) 1 to 1596 polyacrylic acid polymer or salt;
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(f) 0 to 30% ulkali metal carbonate;
( g) 0 ,1 to 6% chlorine bleach stnble, water dispersible organic
detergent active material;
(h) ~ to G% chlorine bleach stable foam depressant; und
(i) 0-30~ sodium sulfate.
The present invention also provides a method for cleaning dishware,
glassware, china and the like in an automatic dishwashing muchine with an
aqueous wash bath contnining an effective amount of the automatic
dishwasher detergent (ADD) powder composition us described above.
According to this aspect of the invention, the ADD composition is a dry,
free flowing powder and can be readily poured into the dispensing cup of
the automatic dishwashing machine and will remain within the dispensing cup
until subjected to the water spray from the dishwashing machine.
The invention will now be described in greater detail by wsy of
speciSc embodiments thereof.
In accordunce with the present invention un improved uutom4tic
dishwasher detergent composition is prepared by incorporating small
amounts of a silica anti-filming agent or silica anti-filming agent and
polyacrylic acid polymer or salt anti-spotting agent in a dishwasher
composition .
The present invention is based upon the discovery that substantially
improved anti-filming and/or anti-spotting properties can be obtained by
adding to the powder detergent composition a small effective amount of a
silica anti-filming agent or silica anti-filming agent and polyacrylic acid
polymer or salt anti-spotting agent.
ANTI-FILMlNG AGENTS
The anti-filming agent comprises a nonabrasive amount of small
substantially water insoluble particles. The anti-filming agent can be a
member selected from the group consisting of silica, alumina and titanium
dioxide and mixtures thereof.
....
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Silica
The silica nnti-filming agent materials that can be used are fumed or
precipitated synthetic or natural silica. The silica may be amorphous or
crystalline .
The silica material that is used may contain up to about 0.1 to 5%
alumina (A1203 ), usually up to about 0 . 5 to 396 and more usually about 1%
alumina, based on the weight of silica.
A preferred silica material is Syloid 249 which is amorphous silica, has
a particle size of about 4 microns and is provided by W . R . Grace Co .
Another suitable silica material is Silox 15, olso from W.1~. Grace Co.,
which has a particle size of about ~ microns.
Another preferred silica material is Huber Zeo 49 which i9 amorphous
silica and is provided by J . M . Huber Corporation and contains about 1%
alumina (A12O3). The presence of as little as 1% A12O3 is found to help
reduce the hydrolysis and subsequent solubility of the silic~ in the highly
alkaline automatic dishwashing detergent composition.
The particle size of the silica material that is used is important in
achieving the desired anti-filming properties.
The silica particles that are used are finely divided and can have a
particle size of about 0.10 to 10 microns, preferably 0.50 to 8 microns and
more preferably about 1. 0 to 5 . 0 microns . The silica particles of this size
and the amount used herein are not abrasive.
The finely divided silica material particles in the dishwashing wash act
to coagulate proteinaceous particulate soils and keeps them in suspension to
2~ prevent them from depositing on the clean glas~ and dishware to form a
film.
Alumina
The alumina material that can be used as an anti-filming agent is
commercially available and i9 insoluble in water and has the formula A12O3.
Suitable materials are available under the tradenames Alumina Oxide C,
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available from Degussa Comp~ny und C~t~pal D, available from Vist~ Corp.
Preferred aluminu matcrials are fumed alumina and a precipitated alumina.
Titanium Dioxide
The titanium dioxide material that cnn be used as an anti-filming agent
is insoluble in water and has the formula TiO2. Suitable materials are
available under the tradenames Titanium Dioxide P25, available from Degussa
Co. Preferred titanium dioxide materials are fumed titanium dioxide and
precipitated titanium dioxide.
The particle size of the alumina and titanium dioxide material that are
used is importnnt in achieving the desired anti-filming properties.
The alumina or titanium dioxide particles that are used are finely
divided nnd can have a particle size of about 0 . 01 to 10 microns, preferably
0 . 01 to 8 microns and more preferably about 0 . 020 to 9 . 0 microns . For
example, a suitable particle size is about 0.01 to 0.50 microns. The alumina
lS and titanium dioxide particles of this size and in the amount used herein
are not abrasive.
The finely divided alumina or titanium dioxide material pnrticles in the
dishwashing wash act to coagulate proteinaceous particulate soil~ and keeps
them in suspension to prevent them from depositing on the clean glass and
20 - dishware .
Without intending to limit the invention in anyway it is theorized that
the alumina and titanium dioxide anti-filming agents function in the following
manner. The glnss surface of vitreous glassware contain negative charged
on their surface through the Si-O bonds; Usually the oxygen atoms carry
these charges. It is postulated that these negatively charged ions will
attrsct positively charged particles and thereby will form an "artificial soil"
layer. This protective mono-layer will then repel the regular food soil and
will increase the anti-redeposition property of the automatic dishwashing
detergent. The alumina and titanium dioxide particles, respectively, will
generate positively chnrged particles which will bond themselves to the
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glassware surface to form the artificial soil layer which will prevent the
formation of film.
The arnount of silica, aluminu or titunium dioxide anti-filming agent
that can be used to achieve the desired improvement in film will depend on
the hardness of the water, detergent active compound, inorganic salts and
other ADD ingredients. The silica, alumina or titanium dioxide anti-filming
agents are particularly effective in hard wash water of, for example, 300
ppm hardness or more.
The amount of each of the silica, alumina or titanium dioxide anti-film
agent that is used can be about 0.5 to 5%, preferably about 1 to 4% and
more preferably about 1. 5 to 3% by weight based on the weight of the
entire composition.
The silica, alumina and titanium dioxide can each be used alone or one
or more of them can be used mixed together. When the anti-filming agents
are used mixed together the weight percent amounts mentioned above are
the totol for the anti-film agent ingredients used in the mixture.
ANTI-SPOTTING AGENTS
Polyacrylic Acid Polymers And Salts Thereof
The polyacrylic acid polymers and salts thereof anti-spotting agents
that can be used are generally commercially available ~nd are briefly
described as follows.
The polyacrylic acid polymers and salts thereof that can be used
comprise water soluble low molecular weight polymers having the formula
11
R3 COOM n
wherein the R1, R2 and R3 can be the same or different and can be
hydrogen, C1-C4 lower alkyl, or combinations thereof. The value of n is 5
to 1000, preferably, 10 to 500, and more preferably 20 to 100, M
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represents hydrogen, or an alkali metal such as sodium or potassium. The
preferred substituent for M is sodium.
The preferred Rl, R2 and R3 groups are hydrogen, methyl, ethyl and
propyl. Preferred acrylic ncid monomer is one where R1 to R3 are
hydrogen, e. g. ~crylic acid, or where R1 and R3 are hydrogen and R2 is
methyl, e.g. methyl ucrylic acid monomer.
The degree of polymerization, i. e . the value of n, is generally
determined by the limit compatible with the solubility of the polymer in
water. The terminnl or end groups of the polymer are not critical and can
be H, OH, CH3 or a low molecular weight hydrocarbon.
The polyacrylic acid polymers and salts thereof can have a molecular
weight of 500 or 1,000 to 100,000, preferably 1,500 to 80,000 and especially
preferably 2,000 to 50, 000 .
, Specific polyacrylic acid polymers which can be used include the
Acrysol LMW acrylic acid polymers from Rohm and Haas, such as the
Acrysol LMW-45N, a neutralized sodium salt, which has a molecular weight
of about 4, 500 and Acrysol LMW-20NX, a neutralized ~odium salt, which hns
a molecular weight of about 2,000. Other polyacrylic acid polymers or salts
thereof that can be used are: Alcosperse 199, molecular weight 2000,
Alcosperse 123, moleculsr weight 4500, Alcosperse 107, moleculnr weight
3000, Alcosperse 129, molecular weight 2000, and Alcosperse 602N molecular
weight 4500, all of which are availnble from Alco Chemical Corp. The low
molecular weight acrylic acid polymers can, for example, have n molecular
weight of about 1,000 to 10,000. Another polyacrylic acid polymer that can
be used is Alcosperse 110 (from Alco) which is a sodium salt of an organic
polycarboxylate nnd which hus a molecular weight of about 100,000.
The nbove polyncrylic acid polymers and salts thereof can be made
using procedures known in the art, see for example U.S. Patent 4,203,858,
The amount of polyacrylic acid polymer or salt that can be used to
achieve the desired improvement in anti-filming and anti-spotting properties
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will depend on the hardness o the water I detergent active compound,
inorganic salts and other ADD ingredients.
The polyacrylic acid or salt anti-spotting agent is particularly effective
in reducing spotting in hard water of, for example, 300 ppm hardness or
more .
Generally, the amounts of the polyacrylic acid polymer or salt
anti-spotting agent that can be used are in the range of from about 1. 0 to
15%, preferubly from about 2 . O to 12%, especially preferably about 4 to 10% .
BVILDER SALTS
Generally, ADD effectiveness is directly related to (a) available
chlorine levels; (b) alkalinity; (c) solubility in washing medium; and (d)
foam inhibition. It is preferred herein that the pll of the ADD composition
be at least about 9 . 5, more preferably from about lO . 5 to 13 . 5 and most
preferably st least about 11. 5 .
The amount of alkali metal silicate added and the amount of slkali metal
TPP added can be used to obtain the desired alkalinity. The sodium
carbonate can be added to act as a buffer to maintain the desired pH level
in the wash bath. The sodium carbonate can be added in an amount of 0 to
30 wt.%, preferably 5 to 25 wt.% and typically about 8 to 20 wt.% of the
detergent composition. The sodium'carbonate can be added for example in
an amount of 15 to 20 wt.g6.
The compositions of the present invention can contain inorganic builder
salts such as NaTPP or organic builder salts such as the alkali metal salts
of citric and tsrtaric acid.
A preferred solid 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 .
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Specific examples of such builders are sodium tetraborate, sodium
pyrophosphate, potassium pyrophosphate, sodium bicarbonate, sodium
hexametaphosphate, sodium sesquicarbonate, sodium mono and
diorthophosphate and potassium bicarbonate.
The NaTPP may be employed in the ADD composition in a range of 20
to 70%, preferably about 20 to 60 wt.%, and more preferably about 25 to 45
wt.96, for example 20 to 40%. The NaTPP may be anhydrous or hydrated,
including the stable hexahydrate with a degree of hydration of 6
corresponding to about 18~ by weight of watel or more.
Since the compositions of this invention are generally highly
concentrated, and, therefore, may be used at relatively low dosages, it is
desirable to supplement any phosphate builder (such 8S sodium
tripolyphosphate) with an auxiliary builder such as an alkali metal
polycarboxylic acid. The NaTPP may be replaced in whole or in part by
the alkali metal polycarboxylic acid. Suitable alkali metal polycarboxylic
acids are alkali metal salts of citric and tartsric acid, e. g. monosodium and
disodium citrate tanhydrous). The sodium salts of citric and tartaric acids
are preferred.
Alkali metal sulfates, preferably sodium sulfate is added as an
anhydrous filler material. The sodium sulfate can be added in an amount of
0-30%, preferably 5 to 25%, and more preferably 10 to 20% by weight of the
composition .
Foam Inhibitors
Foam inhibition is important to increase dishwasher machine efficiency
and minimize destabilizing effects which might occur due to the presence of
excess foam within 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 foam is also
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somewhat dependent on the hardness of the wash wuter in the machine
whereby suitable ndjustment of the proportions of NaTPP which has a water
softening effect may aid in providing the desired degree of foam inhibition.
However, it is genernlly preferred to include a chlorine bleach stable foam
S depressant or inhibitor. Particularly effective are the alkyl phosphonic acid
esters of the formula
ll
I-10--P --R
OR
available, for example, from BASF-Wyandotte (PCUK-PAE), and especially
the alkyl acid phosphate esters of the formula
O ' .
HO--P--OR
OR
available, for exsmple, from Hooker (SAP) and Knapsack (LPKN-158), in
which one or both R groups in ench type of ester may represent
p y 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 same type, may be employed. Especially preferred i~ a mixture of
mono- and di-C16 18 alkyl acid phosphate esters such as
monostearyl/distearyl acid phosphates 1,2/1 (Knapsack). When employed,
proportions of O . 01 to 6 wt . %, preferably O .1 to 5 wt . %, especially about
O .1 to O . 5 wt . %, of foam depressnnt in the composition is typical. The
weight ratio of detergent active component to foam depressant generally
ranging from about 15 :1 to 2 :1 and prefernbly about 10 :1 to 4 :1. Other
defoamers which may be used include, for example, the known silicones.
Although any chlorine bleach compound may be employed in the
compositions of this invention, such as sodium hypochlorite and calclum
hypochlorite, sodium dichloro-isocyanurate, dichloro-dimethyl hydantoin,
and chlorinated TSP, sodium dichloro-isocyanurate is preferred. The
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composition should contain sufficient chlorine bleach compound to provide
about 0 . 5 to 8 . 0% by weight of available chlorine, as determined, for
exnmple, by acidification of the composition with surfuric acid. A solution
containing about 0.9 to 14,3% by weight of sodium dichloroisocyanurate
contains or provides roughly the same percentage of available chlorine.
The composition can preferably contain about 1 to 3% available chlorine.
For example, n solution contnining about 1.8 to 5.4% by weight sodium
dichloroisocyanurate dihydrste contains about 1 to 396 by weight of available
chlorine and is especial}y preferred.
The sodium silicate, which provides Dlkalinity nnd protection of hnrd
surfaces, such as fine china, is employed in an amount ranging from about
5 to 40 wt . %, prefernbly about 8 to 35 wt . ~, and more preferably about 10
to 25 wt . %, in the composition. For example the composition can contain 8
to 25% sodium silicate. The sodium silicate also protects the washing
machine from corrosion. The sodium silicate can have a Na20: SiO2 ratio of
1,6/1 to 1/3,2. The sodium silicute can be added in the form of a dry
powder or an aqueous solution, preferably having an Na20: SiO2 ratio of
from 1/1 to 1/2.8, for example, 1/2,4. Potassium silicates of the same
ratios can also be used. The preferred ulkali metal silicates are sodium
disilicate and sodium metasilicate.
Most of the other components of the composition, especially calcium
hypochlorite and foam depressant can be added in the form of dry powders
or aqueous dispersions or solutions.
The detergent active materials used in the present invention are
2 5 selected to be stable in the presence of chlorine bleach . The organic
nonionic and anionic detergents can be used.
Liquid Nonionic Surfactant Detergents
The liquid nonionic surfactant detergents that can be used in the
practice of the present are preferably the low foam nonionic surfactants.
2V31289
Useful nonioIlics are represented by the low foam Plurafac series from
BAS~ Chemicul Company which are the reaction product of a higher linear
alcohol and a mixture of ethylene and propylene oxides, contuining 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
condensed with 7 moles propylene oxide and 4 moles ethylene oxide and a
C13-C15 fatty alcohol condensed with 5 moles propylene oxide and 10 moles
ethylene oxide.
Other useful surfact~nts are Neodol 25-7 and Neodol 25-6.5, which
products are made by Shell Chemical Company, Inc. The former is a
condensation product of a mixture of higher fatty alcohols averaging about
12 to 15 carbon atoms, with about 7 mols of ethylene oxide and the latter i9
a corresponding mixture wherein the carbon atom content of the higher
fatty alcohol is 12 to 13 and the number of ethylene oxide groups present
averages about 6, 5 . The higher alcohols are primary alk~nols . Other
example~ of 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 alkanol 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 5596 by weight random distributed
oxyalkyl groups of which 42% are ethoxy and 58% propoxy groups.
Another nonionic surfactant that can be used in accordance -with the
present invention has the following formula
R-O-(PO)X-lEOlPO)H
16
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R is an alkyl group having 8 carbon atoms, PO is a propylene oxide
polymer attached directly to the oxygen of the alkyl group, x is 8 to 9,
EOIPO represents a copolymer of ethylene oxide and propylene oxide in
which the ethylene oxide and propylene oxide are randomly mixed. The
molnr ratio of EO/PO is about 2 :1 to 5 :1, e. g. about 3 :1. The total
number of EO and PO groups in the copolymer ure such that the number of
EO and PO groups are 5 to 8 and the cloud point of the nonionic surfactant
is about 20 to 30C.
A method of making the nonionic surfactant and a more complete
description of the nonionic surfactant i8 given in the EPA published patent
application 0086493 dated August 24, 1983 which i9 incorporated herein in
its entirety.
Other useful nonionic surfactants are the Poly-Tergent S-LF
surfactants available from Olin Corporation. These surfactants are low
foaming, biodegradable linear fatty alcohols. Surfactants of this type sre
available under the tradenames Poly-Tergent S-LF 18, Poly-Tergent
S-305-LF, Poly-Tergent S-405-LF and Poly-Tergent CS-1
Mixtures of two or more of the liquid nonionic surfactants can be used
and in some cases advantages can be obtained by the use of such mixtures.
The detergent active materials used herein must be stable in the
presence of chlorine bleach, especially hypochlorite bleach. 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 14) alkyl diphenyl oxide mono andlor
disulphonates, commercially available for example as DOWFAX (Registered
Trademark) 3B-2 and DOWFAX 2A-l
Other suitable surfactants include the primary alkyl sulphates, alkyl
sulphonates, alkylaryl-sulphates and sec. alkyl sulphates. Examples include
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sodium C10 18 alkyl sulphates such as sodium dodecyl sulphate and sodium
tollow alcohol sulphate; sodlum C10 18 alkane sulphonates such as sodium
hexadecyl-1-sulphonate and sodium C12 18 alkylbenzene sulphonates such as
80dlum dodecylbenzene sulphonates. The corresponding potassium salts may
also be employed.
Surfactants of the foregoing type, all well known in the art, are
described, for example, in U.S. Pntents 3,~85,668 and 9,271,030, which are
incorporated herein by reference thereto.
The surfnctants are used in amounts of 0.1 to 6%, preferably 0. 5 to
6.0%, and more preferably about 1.0 to 5.0%, for example 2 to 9%.
Various conventional ingredients may be included in these compositions
in small amounts, generally less than about 4 wt . ~6, such as perfume,
hydrotrop;c agent~ such as the sodium benzene, toluene, xylene and cumene
sulphonates, preservatives, dyestuffs and pigments and the like, all of
course being stable to chlorine bleach compound and hlgh alkalinity.
Especlally preferred for colorlng are the chlorinated phthalocyanines and
polysulphides of aluminosilicate which provide, respectively, pleQsing green
and bluc tints.
The powder ADD compositions of this invention are readily employed in
known manner for washing dishes, glasses, CUp8, 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 sn embodiment of the invention a powder autom~tic dishwsshing
2S detergent composition is formulated using the below named ingredients.
2031289
Preferred
Component Wcight Percent Weight Percent
Sodium Tripolyphosphate 20-60 20-gO
Sodium Carbonate 0-30 8-20
Sodium Sulfate 0-30 10-20
Surfactant 0, 5-6 1-5
Sodium Silicate 8-35 8-25
Silica Anti-filming Agent 1-4 1,5-3
Sodium Polyacrylate 1-15 4-10
Anti-spotting Agent
Sodium Dichloroisocyanurate 0 . 5 to 5 1. 0 to 3 . 0
(Available Chlorine)
Color, Perfume 0.5 to 3.0 1 to 2
Moisturc 2-1~ 8-10
The powder detergent composition can be prepared as a regular
strength composition containing sodium carbonate and sodium sulfate or as a
concentrate composition in which all or a portion of each of the sodium
carbonate and sodium sulfate have been omitted.
The dishwasher detergent compositions of the present invention can
contain conventional dishwashing detergent composition additives. The
formulations can be prepared with commercially available powder builders,
chlorine bleach source compounds and surfactant compounds.
The formulations can be prepared using the conventional dry blending
and agglomeration procedures used for the preparntion of dry powder
detergent compositions.
In dry the blending procedure, nonionic surfactant is thoroughly
mixed with STPP by overspraying it at 120F in a twin-shelled mixer. The
STPP beads containing absorbed surfactant are then conditioned, that is
allowed to sit overnight. The loaded STPP material is then successively
mixed with anti-filming agent or anti-filming agent and polyacrylate acid
polymer or salt, sodium carbonate, sodium sulfate and sodium silicate
'
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granules. Finnlly sodium dichloroisocyanurllt~ is ~ldded nnd blended with
the rest and mixed thoroughly in the mixer.
Another method for preparing the automatic dishwasher detergent
powder compositions of the present invention is the agglomeration
procedure. The agglomeration procedure provides better bleach stability by
coating the nonionic surfactant with the sodium silicate which separates the
nonionic surfactant from the reactive bleach.
In accordance with the agglomeration procedure, about half of the
STPP builder salt in the form of powder granules is introduced into a
rotary drum and sprayed with the nonionic liquid surfactant at a
temperature of about 120F. The STPP granules during the spraying
operation are maintained at a temperature of about 100F.
The STPP granules loaded with the nonionic surfactant are dried
overnight. The loaded dried STPP is mixed with the remaining STPP,
anti-filming agent or unti-filming agent and polyacrylic acid or salt, sodium
carbonate and sodium sulfate in an agglomerator.
An aqueous solution of sodium silicate is then sprayed on the mixed
powders in the agglomerator.
The mixed agglomerated powders are then added to a granulator in
order to sieve out the desired particle size of the agglomerate. From the
granulator the powder composition is fed to a fluid bed drying unit to dry
the powder. Finally, sodium dichloroisocyanurate is post added and
blended with agglomerated granules to complete the process.
One or more ingredients can be omitted or additional ingredients such
as perfumes and anti-foam agents can be added to the composition.
The order of adding the solid powder ingredients to the agglomerator
is not particularly critical as long as good mixing is achieved.
The term dry powder composition~ as used herein is intended to
include free flowing powder compositions containing 0-15% moisture, typically
2-1496 and more typically 4-1296 moisture,- for example 8-10%, The moisture
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can be present in the form of hydrated compounds, for example, sodium
tripolyphosphate hexahydrate, hydrated sodium carbonate, hydrated sodium
sulfate and dichloroisocynnur~tc dihydrnte ~In(l/or ln tlle form Or unboun~l
water. It is preferred that the composition contain less than about 10%
moisture as unbound water.
All amounts and proportions referred to herein are percent by weight
of the composition unless otherwise indicated.
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.
21
2031289
Example 1
In accordance with the present invention automatie dishwasher powder
detergent compositions are formulated using the below named Ingredients in
the amounts indicated.
A B
Prior Art
. Invention Commercial
Ingredient Powder (Wt . ~)Powder (Wt . %)
Sodium Tripolyphospate 3q,8 34.8
Sodium Carbonate 19 . 0 19 . 0
Sodium Sulfate 19 . 0 21. 5
Nonionie Surfaetant( ) 3.0 3.0
Sodium Silicate (1:2.4) 12.0 12.0
Siliea Anti-filming Agent 2.5 --
Sodium Dichloroisocyanurate Dihydrate(2) 1.8 1,8
Moisture . 7 9 7 9
100, 00 100 . 00
(1) Tergitol MDS-42, from Union Carbide Corporation.
1$ (2) ACl 56, 1% availabIe ehlorine, Monsanto Corporation.
The two above formulations (A) and (B) are tested and eompared for
film and spot formation. The formulations are tested in a Kenmore
automatie dishwasher using the proeedure described in ASTMD 3566-79,
exeept that only four eleaning eyeles are used. The filming and spotting
are evaluated aeeording to the following seales:
Film Rating Seale
1. Best, no apparent film
a. Filming slight, becoming upparent
3. Notieeable film, increasing
4. Continued increase of signifieant film
5, Filming becoming excessive
6. Filming high, exeessive buildup
7, Continued increase of excessive film.
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Spot Ratin~ Scale
A. Best - no spots
B, Very few spots apparent
C. Distinct
D. Significant coverage approximntely 50~.
The above compositions are tested cleaning glass tumblers.
The ASTM Method D3556-7~ for the deposition on glassware during
mechanical dishwashing, as mentioned above, is used to evaluate the
buildup of spots and film on glassware. 50 grams of the invention powder
detergent composition (A) and 50 grams of the commercial powder detergent
composition (B) detergent are used in each test. All testing reported is
done in Kenmore Model 587,1548580 and/or model 587.154G580 Automatic
Dishwasher, The water wash temperature is 120F and the water has 300
ppm hardness,
The results obtained in the fourth cycle are reported below,
Formulation Spot Film .
Invention Formulation (A) B-C 1-2
Commercial Formulation (B) B-C 4-5
The commercial powder gives more film than the invention powder ADD
compositions. There is no difference in the spot scores.
23
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Example 2
Following the ~eachings of the present invention powder uutomatic
dishwasher detergent compositions ure formulated using the below named
ingredients in the amounts indicated.
In order to demonstrate the improvement in anti-filming and
anti-spotting performance three powder formulations are prepared. The
first formulation (A) contains 2.24 wt.~ silica anti-filming agent, the second
formulation (B) contains 2.24 wt.% silica anti-filming agent and 8 wt.%
sodium polyacrylate and the third formulation (C) contains no silica and no
sodium polyacrylate.
Formulations
A B C
Wt.% Wt.% Wt.%
N TPP(1) 34.50 34.50 34.50
Sodium Sulfate 18.86 10.86 21.10
Sodlum Carbonate 17, ~0 17,90 17,90
Sodium Silieate 10.00 10,00 10,00
Nonionie Surfactant 3,10 3,10 3,10
Silica Anti-filrning Agent 2.24 2,24 --
Na Polyacrylate(4) -- 8.00 --
Sodium Diehloroisocyanurate Dihydrate(5~ 1,80 1.80 1,80
Moisture 11,60 11,60 11,60
~ 100.00100.00100,00
1. The NaTPP contains a minor amount of Na pyraphosphate and a minor
amount of Na orthophosphate.
2. The nonionie surfactant is Tergitol MDS-42.
3. The siliea anti-filming agent is Syloid 244 silica.
4. The water soluble Na polyaerylate agent is Alcosperse 149-D 2000 MW.
5. ACl 56, 1 wt.% available chlorine.
24
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A dose size of 50 grams of cach of formulations (A), (B) and (C) are
used to evaluate the efficacy of the anti-filming and anti-spotting agents.
The invention formulations (A) and (B) are evaluated with regard to
film and spot against the commercial formulation (C) under 300 ppm water
hardness in 4 cycle ASTM runs at 120F water wash temperature in e~ch
test .
There are 10 glass tumblers used in each test. All three products are
tested in the same GE dishwasher to minimize the machine effect. The
results obtuined in each of the tests are reported below.
Performance Profile
ASTM Test 300 ppm hard water, 120F
Glass Tumblers Invention Invention Commercial
Average Value Formulation (A) Formulation (B) Formulation (C)
of 10 Tumblers Spot Film Spot Film Spot Film
15 1 Cycle B 1 A 1 B 3
2 Cycle B 1. 5 A 1. 5 B-C 3 . 5
3 Cycle B-C 2 A-B 2 B-C 4
4 Cycle B-C 2-2.5 A-B 2-2.5 B-C 4-5
The invention formulation (A) performs better than commercial
formulation (C) with regard to film formation. The inventive formulation
(B ) performs better than invention formulation ~A) with regard to spot
formation and better than commercial formulation (C) with regard to spot
and film formation.
The above mentioned three products are also tested using 6 Melamine
plates in each test.
¦ T results obtatned tn ellch Or the tcuts ere reported below.
1~ 25
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Performance Profile
ASTM Test 300 ppm hard water, 120F
Melamine Invention Invention Commercial
Plate,s, Average Formulation (A) Formulation (B) Formulation (C)
5Value 6 Plutes Spot Film Spot Film Spot Film
1 Cycle A-B 1 A 1A-B
2 Cycle A-B 1 A 1 B 1
3 Cycle A-B 1 A-B 1B
4 Cycle A-B 1 A-B 1B-C 1
All three of the formulations gave no film. The inventive formulatlons
(A) and (B) both performed substantially better against the commercial
formulation (C) with regard to spot formation. The invention formulation
(A) containing silica did not perform quite as well as invention formulation
(B) containing silica and sodium polyacrylute with regard to spot formation.
The above duta show that the add,ition of silica anti-fllming agent or
silica and polyacrylate anti-filming agents give improved performance against
filming on glassware and dishware.
26'
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Example 3
Following the teachings of the invention a concentrate automatic
dishwasher powder detergent composition is formulated using the below
named ingredients.
Ingredient Weight Percent
Sodium Citrute Builder Salt 50, 0
Sodium Carbonate
Sodium Sulfate
Nonionic Surfactant 4 . 0
Sodium Silicate (1:2.4) 18,0
Silica Anti-filming Agent( ) 5.0
Na Polyacrylate Anti-filming Agent(2) 16,0
Sodium Dichloroisocyanurate Dihydrate(3) 2.8
Moisture 4 . 2
1~0
(1) Syloid 244 Sil}ca
(2) Alcosperse 14~-D
(3) ACl 56, 1,6% available chlorine.
About 28 grams of the above concentruted formulation, i. e . about one
half the normal dose, i9 tested in an automatic dishwasher machine to clean
2 0 gluss tumblers .
The tumblers after u normul wash cycle are removed from the
dishwasher and are found to be free of spots and to contain only a slight
amount of film.
~7
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Example 4
Automatic dishwnshing powder detergent compositions are formulated
from the following ingredients in the amounts specified.
Invention Comparison
Formulation Formulation
Alumina No Alumina
Anti-film Agent Anti-film Agent
Component Wt. % Wt %
NaTPP 34 oo 34 oo
Knapsack LPKN-158 Foam Depressant 0.16 0.16
Sodium Carbonate ( anhydrous)15 . 00 15 . 00
Sodium Silicate (l/2,4) 15,00 15.00
Sodium Sulfate 24, 04 26, 04
Alumina Anti-filmin g Agent ( 1)2 . 00 ___
Poly Tergent SLF-18(2) 2 . 00 2 . 00
Sodium Dichloroisocyanurate Dihydrate(3) 1.80 1.80
Moisture 6 . 00 6, 00
100.00 100.00
(1) Aluminum oxide C has a particle size of 0.02 microns and is available
from Degussa Co,
(2) Nonionic Surfactant, Olin Corp,
~3) ACl 56, 1,0% available chlorine.
The ingredients are added in the order listed and mixed until a
homogeneous powder mixture is obtained. The formulations are tested by
washing glassware at 120F in hard water (300 ppm hardness).
20The two formulations are tested and compnred. The formulntions nre
tested in a Kenmore nutom~tic dishwasher to clean glas~ tumblors usin~ the
procedure described in ASTMD 35,66-79, except that only four cleaning
cycles are used. The spotting and filming are evaluated as in Example 2
and the results obtained in the fourth cycle are reported in the below
2 5Table .
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TAB LE;
Performance Rating
Spot Film
Invention Formulution Silica Anti-filming Agent B-C
Comparison Formulation
No Alumina Anti-filming Agent B-C 4
The two formulations perform about the same on spot. The invention
formulation performs substantially better on film.
29
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Example 5
The above Example 4 is repeated with the difference that 2 . 00 wt . %
titanium dioxide is substituted for the alumina anti-filming agent. The
formulations are tested by washing glassware at 130F in hard water (30Q
ppm hardness) as before. The results obtained in the fourth cycle are
reported in the below Table.
TAB LE
Performance Rating
Spot ~l~ilm
Jnvention Formulation (Titanium Dioxide) 1
Comparison Formulation
(No Anti-filming Agent) B-C 4
The two formulations perform about the same on spot. The invention
formulation performs better on film.
The automatic dishwasher powder detergent compositions of the present
invention provide improved film snd/or improved spot properties on
glassware and dishware.
15' The invention is not to be limited by the above disclosure and
examples which are given as illustrations only. The invention is to be
interpreted in accordance with the below claims.
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