COMPOSITION ET METHODE ANTI-INCRUSTATION POUR TISSUS

COMPOSITION AND METHOD FOR FABRIC ENCRUSTATION PREVENTION

Abrégé anglais

COMPOSITION AND METHOD FOR FABRIC ENCRUSTATION PREVENTION
Abstract of the Invention
Cleaning composition and method comprising in a
first embodiment an alkali metal carbonate builder and a
fabric encrustation prevention system comprising a
substoichiometric level of a polyamino polycarboxylic acid or
water-soluble salts thereof which acts to inhibit and prevent
the deposition of insoluble precipitates containing water
hardness ions on fabrics; in a second embodiment the cleaning
composition includes a detersive surfactant for laundry
applications; in either embodiment the following adjuncts may
be included: co-builders, alkali metal silicates, bleaching
species, enzymes, fragrances, dyes, brighteners and others.
310.102 -28-

Revendications

WHAT IS CLAIMED IS:
1. A non-phosphate fabric cleaning composition
comprising:
(a) a building effective amount of an alkali metal
carbonate detergent builder from about 20 to about 80 weight
percent; and
(b) a fabric encrustation preventing amount of an
encrustation preventing system, including a substoichiometric
amount of a polyamino polycarboxylic acid or a water-soluble
salt and mixtures thereof, having the formula
<IMG>
wherein M is selected from the group consisting of:
(1) <IMG> ; (2) <IMG> ; (3) -CH2CH2-;
(4) -CH2CH2OCH2CH2OCH2CH2-; and
(5) <IMG>
and water soluble salts thereof; and where R1, R2, R3 and R4
are selected from the group consisting of -(CH2)nOH,
-CH2COOH, and -H wherein n is 1, 2 or 3; provided that when
M is (1), (2), (3) or (4) then at least three of R1, R2, R3
and R4 are -CH2COOH; and further provided that when M is
(5) at least R1 and R2 or R3 and R4 are each -CH2COOH,
individually.
2. The composition of Claim 1 wherein the amount of
alkali metal carbonate builder is from about 30 to about 70
percent by weight.
310.102 -21-

3. The composition of Claim 1 wherein the amount of
said polyamino polycarboxylic acid or a water- soluble salt
thereof is from about 1 to about 20 percent by weight.
4. The composition of Claim 1 wherein the said
composition includes a detersive cleaning-effective amount of
a surfactant, selected from the group consisting of anionic,
nonionic, cationic, amphoteric surfactants and mixtures
thereof.
5. The composition of Claim 4 wherein said
surfactant is selected from the group consisting of alkyl
sulfates, primary and secondary alkyl sulfonates, linear
alkyl aryl sulfonates, alkyl ether sulfates, alkoxylated
aliphatic alcohols, alkoxylated alkyl phenols, copolymers of
C1-4 alkylene oxides, and mixtures thereof.
6. The composition of Claim 1 and further including
a bleaching effective amount of a bleaching species.
7. The composition of Claim 1 and further including
a non-encrustation promoting amount of a co-builder selected
from the group consisting of silicates, citrates, alkali
metal carbonates, polymeric polycarboxylic acids, zeolites,
salts of ethylene diamine tetraacetic acid and sodium
nitrilotriacetate.
8. The composition of Claim 7 wherein the
co-builder is a non-encrustation promoting amount of zeolite.
9. The composition of Claim 1 and further including
about 1-10% of an alkali metal silicate.
310.102 -22-

10. The composition of Claim 1 wherein said alkali
metal carbonate is sodium carbonate; and said polyamino
polycarboxylic or water-soluble salt is selected from the
group consisting of 1,3-diamino-2-hydroxypropane
N,N,N',N'-tetra-acetic acid, 1,2-diaminopropane N,N,N',N'-
tetraacetic acid, ethylenediamine tetraacetic acid (EDTA),
N(2-hydroxyethyl)-ethylenediamine N,N,N'-triacetic acid,
ethylenediamine N,N'-diacetic acid, triethylenetetramine
hexaacetic acid, and ethylene bis(oxyethylene nitrilo)
tetraacetic acid.
310.102 -23-

11. A non-encrustation fabric cleaning composition
consisting essentially of
(a) a building effective amount of an alkali metal
carbonate from about 20 to 80 weight percent;
(b) from about 1 to about 10 percent of a sodium
silicate having a ratio of SiO2/M2O of about 1 to about
4, wherein M is an alkali metal;
(c) a substoichiometric amount of a polyamino
polycarboxylic acid or water-soluble salt and mixtures
thereof having the formula
<IMG>
wherein M is selected from the group consisting of:
(1) <IMG>; (2) <IMG; (3) -CH2CH2-;
(4) -CH2CH2OCH2CH2OCH2CH2-; and
(5) <IMG>
and water soluble salts thereof; and where R1, R2, R3 and R4
are selected from the group consisting of -(CH2)nOH,
-CH2COOH, and -H wherein n is 1, 2 or 3; provided that when
M is (1), (2), (3) or (4) then at least three of R1, R2, R3
and R4 are -CH2COOH; and further provided that when M is
(5) at least R1 and R2 or R3 and R4 are each -CH2COOH,
individually;
(d) a detersive cleaning-effective amount of a
surfactant, selected from the group consisting of anionic,
non-ionic, cationic, amphoteric surfactants and mixtures
thereof; and
(e) a bleach effective amount of a bleaching
species.
310.102 -24-

12. The composition of Claim 11 wherein said amount
of alkali metal carbonate is from about 30 to about 70 weight
percent.
13. The composition of Claim 11 wherein the amount
of said polyamino polycarboxylic acid or water- soluble salt
thereof is from about 1 to about 20 percent.
14. The composition of Claim 11 wherein said alkali
metal carbonate is the primary builder and a co-builder
selected from the group consisting of silicates, citrates,
alkali metal carbonates, polymeric polycarboxylic acids,
zeolites, salts of ethylene diamine tetraacetic acid and
sodium nitrilotriacetate.
15. The composition of Claim 11 wherein said
co-builder is a non-encrustation promoting amount of zeolite.
16. The composition of Claim 11 wherein said
surfactant is selected from the group consisting of alkyl
sulfates, primary and secondary alkyl sulfonates, linear
alkyl aryl sulfonates, alkyl ether sulfates, alkoxylated
aliphatic alcohols, alkoxylated alkyl phenols, copolymers of
C1-4 alkylene oxides and mixtures thereof.
17. The composition of Claim 11 where said
polyamino polycarboxylic acid or water-solubles salt thereof
is selected from the group consisting of 1, 3-diamino-2-
hydroxy-propane N, N, N', N'-tetraacetic acid,
1, 2-diaminopropane N, N, N', N'-tetraacetic acid,
ethylenediamine tetraacetic acid (EDTA),
N(2-hydroxyethyl) ethylenediamine N, N, N'-triacetic acid,
ethylenediamine N, N'-diacetic acid, triethylenetetramine
hexaacetic acid, and ethylene bis(oxyethylene nitrilo)
tetraacetic acid.
310.102 - 25 -

18. A method for reducing water causing
precipitation and deposition on fabric comprising contacting
the fabric with a cleaning effective amount of an aqueous
solution of a detergent composition comprising
(a) a building effective amount of an alkali metal
carbonate builder from about 20 to 80 weight percent;
(b) from about 1 to about 10 percent of a sodium
silicate having a ratio of SiO2/M2O of about 1 to about
4, wherein M represents an alkali metal;
(c) a substoichiometric amount of a polyamino
polycarboxylic acid or water-soluble salt and mixtures
thereof having the formula
<IMG>
wherein M is selected from the group consisting of:
(1) <IMG> ; (2) <IMG>; (3) -CH2CH2-;
(4) -CH2CH2OCH2CH2OCH2CH2-; and
(5) <IMG>
and water soluble salts thereof; and where R1, R2, R3 and R4
are selected from the group consisting of -(CH2)nOH,
-CH2COOH, and -H wherein n is 1, 2 or 3; provided that when
M is (1), (2), (3) or (4) then at least three of R1, R2, R3
and R4 are -CH2COOH; and further provided that when M is
(5) at least R1 and R2 or R3 and R4 are each -CH2COOH,
individually;
(d) a detersive cleaning effective amount of a
surfactant, selected from the group consisting of anionic,
non-ionic, cationic, amphoteric surfactants and mixtures
thereof; and
(e) a bleach effective amount of a bleaching
species.
310.102 -26-

19. The method of Claim 18 wherein said amount of
alkali metal carbonate is from about 30 to about 70 weight
percent.
20. The method of Claim 18 wherein the amount of a
polyamino polycarboxylic acid or water-soluble salt thereof
is from about 1 to about 20 percent.
21. The method of Claim 18 wherein the alkali metal
carbonate is the primary builder and a co-builder selected
from the group consisting of silicates, citrates, alkali
metal carbonates, polymeric polycarboxylic acids, zeolites,
salts of ethylene diamino tetraacetic acid and sodium
nitrilotriacetate.
22. The method of Claim 21 wherein the co-builder
is a non-encrustation promoting amount of zeolite.
23. The method of Claim 18 wherein said surfactant
is selected from the group consisting of alkyl sulfates,
primary and secondary alkyl sulfonates, linear alkyl aryl
sulfonates, alkyl ether sulfates, akoxylated aliphatic
alcohols, alkoxylated alkyl phenols, copolymers of C1-4
alkylene oxides and mixtures thereof.
24. The method of Claim 18 wherein said polyamino
polycarboxylic acid or water-soluble salt is selected from
the group consisting of 1,3-diamino-2-hydroxypropane
N,N,N',N'-tetraacetic acid, 1,2-diaminopropane N,N,N',N'-
tetraacetic acid, ethylenediamine tetraacetic acid (EDTA),
N(2-hydroxyethyl)ethylenediamine N,N,N'-triacetic acid,
ethylenediamine N,N'-diacetic acid, triethylenetetramine
hexaacetic acid, and ethylene bis(oxyethylene nitrilo)
tetraacetic acid.
310.102 -27-

Description

COMPOSITION AND M~THOD FOR FABRIC ENCRUSTATION PREVENTION
This invention relates to compositions and methods
for preventing fabric encrustation by decreasing or
suppressing the formation of encrustation residue when using
detergent applications and formulations during fabric washing
operations with "hard water." In particular, this invention
relates to the use of polyamino polycarboxylic ~cids to
prevent growth or deposition of insoluble compounds on fabric
surfaces during washing operations. The invention is
primarily concerned with inhibition and prevention of the
formation and deposition of insoluble compounds on fabric.
The growth of insoluble compounds on fabric
surface (fabric encrustation) from repeated washing with
non-phosphate detergents in "hard water" is a negative effect
in which the appearance and feel of the fabric is affected.
The fabric acquires a rough feel and colored garments have a
faded appearance.
The insoluble compounds primarily are calcium and
magnesium carbonate precipitates caused when hard water
containing calcium and magnesium ions react with builders,
such as sodium carbonate, typically used in non-phosphate
detergents. Therefore, the prevention of encrustation or the
deposition of insoluble compounds formed during the washing
process with "hard water" is strongly desired. Phosphonates
and polyacrylates have been shown to be effective in
detergent applications for the prevention of encrustation.
Phosphonates can function as crystal growth inhibitors which
prevents the growth of insoluble calcium and magnesium
compounds at substoichiometric concentrations. Polyacrylates
can function as sequestering and dispersing agents, as well
as crystal growth inhibitors. Some drawbacks associated with
phosphonates and polyacrylates is that phosphonates can
contribute to euthrophication and polyacrylates are not
biodegradable.
310.102 -1-

~ ~ A ,~
Heavy-duty laundry detergents typically contain
two major ingredients, surfactant and builder, and a number
of other ingredients essential to an acceptable produc~.
Although of lesser importance to detergency, these additional
ingredients impart certain desirable functions to the total
formulated detergent. These miscellaneous ingredients
include anti-corrosion agents, anti-soil redeposition agents,
fluorescent whitening agents, bleaches, enzymes, perfume and
the like. The two major components most essential to
detergency are surfactant and builder.
The surfactant provides detersive action to the
detergent. This is based on their fundamental characteristic
to absorb or concentrate at the soil/fiber/water interfaces.
The detergent builder functions primarily to prevent divalent
calcium and magnesium water-hardness~causing-ions from
interfering with the surfactant action. The builder also may
provide alkalinity and thus improve fatty acid
saponification, buffering capacity, prevent flocculation,
maintain ionic strength, extract metals from soils and remove
alkaline-earth metal ions from the washing solutions.
Phosphates are extremely effective builders; however, they
are in disfavor due to their eutrophication effect on lakes
and streams. Many states in the United States have enacted
legislation limiting phosphate content. Such legislation to
reduce phosphate content has led to a variety of non-
phosphate builders, either proposed and/or employed.
Examples include silicates, zeolites, carbonates and
polycarboxylates, citrates, EDTA and sodium nitrilotriacetate
(NTA). Such alternatives are themselves subject to various
limitations. Silicates are not preferred because they are
not entirely water-soluble and they can therefore deposit
onto fabrics, and also can form precipitates with the
hardness ions. Zeolites are generally effective co-builders,
but not as the sole builder. Polycarboxylate builders are
costly.
310.102 -2-

~igh levels of alkali-metal carbonates have been
found to be a cost effective non-phosphate builder,
particularly in applications where a high pH is required,
e.g., for oily soil removal. A drawback associated with such
high carbonate levels is that calcium and magnesium ions
present in the washin~ water readily form precipitates with
the carbonates,and such precipitates deposit and/or form on
the fabrics. These precipitates leave the fabrics with a
rough feel and faded appearance. Various approaches have
been employed in the art to combat the forma~ion of calcium
or magnesium precipitates, including the addition of seed
crystals, crystal growth inhibitors and non-precipitation
sequestrants. Non-precipitation sequestering and complexing
agents tend to be expensive due to the stoichiometric levels
needed, adding significantly to the overall formula cost.
Discussion of Prior Art
British Patent Specification No. 66492 describes
compositions containing related compounds, such as the
polyamino polycarboxylic acid type or water-soluble salt
thereof, having the property of stabilizing peroxy bleach
compounds.
British Patent Specification No. 1383741 relates
to using the compound 1,3-diamino-propan-2-ol-N,N,N',N'-
tetraacetic acid or water-soluble salt thereof as a
stabilizer against degradation of peroxy compounds.
U.S. Pat. 2,130,505 relates to various
polyaminocarboxylic acids and the process for making the
same. This patent mentions the use of said compounds for
avoiding and rendering harmless the precipitates of
water-insoluble metal salts, particularly formed from the
ions which cause hard water. This patent does not teach or
suggest the use of these compounds at substoichiometric
levels in carbonate base detergent formulations for the
prevention of fabric encrustation. This application is very
ambiguous in that use levels are not given.
310.102 -3-

U. S. Pat. 2,396, 938 relates to treatment of
boilers and various parts thereof for removing coatings of
scale and preventing further scale formation in boilers by
the use of stoichiometric levels of various alkaline,
polyamine, tetra or higher acetic acid compounds.
U.S. Pat. 2,407,645 relates to polycarboxylic
amino acids and the process for producing said acids and
alkali metal salts thereof. The compounds of U.S. Pat.
2,407, 645 are disclosed as useful in water softening
compositions and, when mixed with soap, as washing agents.
U.S. Pat. 4,352,751 relates to various diamine
triacetic acids useful in the formation of fluorescent
chelates of rare earth metal ions which can be employed in
fluoroassay techniques.
Japanese Patent 5pecification 55/133498 relates to
water-soluble deodorizing~ detergent prepared by dissolving
N-long chain acylamino acid salts and others in mineral
water. These compositions are useful as detergents for use
in washing of dishes and exhihit deodorizing and washing
effects, as well as protective effects on human skin.
Japanese Patent Specification 60/11998 relates to
peroxide bleaching compositions containing chelating agents
in the form of N,N-bis-(hydroxvethyl) imino, acetic acid
and/or N-hydroxyethylimino, diacetic acid. These latter
compounds are found useful as bleaching agents having
superior bleaching effects in eliminating yellowing,
striping, decolorization and the like.
Japanese Patent Specification 30/51500 relates to
mild neutral detergent c:ompositions for bathrooms and the
like, containing surfactant detergency-improving potassium or
ammonium salts of aminocarboxylic acids and glycol solvent.
The three components act synergistically on metal salts of
310.102 -4-

'... J.:J~.L.
fatty acids, causing rapid decomposition. The compounds also
prevent the attachment of dirt to items washed therewith.
In view of the art cited, there remains a need for
compositions and methods for effectively preventing fabric
encrustation in detergent applications and formulations. The
prior art relates only to the use of various compounds and
compositions in stabilizing the degradation of peroxy
compounds; reducing hardness of water; removing scale from
boilers and boiler tubes; chelating of rare metal ions
capable of forming fluorescent chelates; and further
employment in fluoroassay techniques.
The present application relates to the method for
using polyamino polycarboxylic acid compounds as effective
fabric encrustation preventatives in detergent applications
and formulations. The prior art relates only to the use of
polyamino polycarboxylic acids to reduce hardness of water,
or as a stabilizer against degradation of peroxy bleaching
compounds. Clearly, the addition of polyamino polycarboxylic
acid compounds into detergent compositions in order to
decrease and/or suppress the formation of encrustation
residue in fabrics from hard water minerals due to the
presence of the sodium carbonate builder in the detergent
formulation is not contemplated by the prior art.
A leading inorganic replacement for phosphate
builders is soclium carbonate. However, high carbonate
content non-phosphate builders produce the problem of "hard
water" precipitates from the calcium and magnesium ions
present in the "hard water." The growth or deposition of the
precipitates on the fabrics during washing application make
carbonate-based detergents, otherwise, not preferred.
It is therefore an object of the present invention
to provide a cleaning composition which does not utilize
phosphate builders.
310.102 -5-

It is another object of the present invention to
provide a high carbonate cleaning composition which results
in reduced levels of calcium and magnesium salt deposition on
fabrics.
It is another object of the present invention to
provide a largely biodegradable compound which prevents
carbonate salt precipitation and/or controls encrustation.
It is another object of the present invention to
provide a cleaning composition which provides good stain and
soil removal performance.
It is another object of the present invention to
provide a cleaning composition and method for the reduction
of fabric encrustation which does not contribute to
euthrophication.
It is yet ancther object of the present invention
to provide a cleaning composition and method for the
reduction of fabric encrustation when using high carbonate or
non-phosphate detergent formulations.
Summary of the Invention
It has now been found that by using the
compositions and method in accordance with the present
invention, fabric encrustation can be reduced or eliminated
when using high carbonate, or non-phosphate detergents with
water containing calcium and/or magnesium ions. The
compositions and method are characterized by utilizing
polyamino polycarboxylic acid and derivatives thereof. More
preferably, this invention relates to the use of polyamino
polycarboxylic acids and water-soluble salts thereof,
especially 1,3-diamino-2-hydroxypropane-N,N ! N',N'-tetraacetic
acid in the detergent compositions and methods utilizing said
compositions.
310.102 -6-

More particularly, this invention relates to the
use of detergent compositions which contain 1,3-diamino-2-
hydroxypropane N,N,N',N'-tetraacetic acid or a water-soluble
salt thereof witn monovalent cations in a concentration of
from about 1 percent to about 20 percent by weight; with a
preferred range of about 2 to about 12 percent; more
preferably from about 1 percent to about 5 percent.
Alkali metal salts, particularly sodium salts,
potassium salts or ammonium salts, can be used as water-
soluble salts of polyamino polycarboxylic acids having
monovalent cations. Ammonium ions also can be regarded as
monovalent cations for the purpose of the present invention.
It is noted that for the purpose of the present invention the
acid forms of the polyamino polycarboxylic acid are
equivalent to the salt fcrms except where the acid has
limited solubility. It is also noted that except where
explicitly stated or implied from the context, the acid and
salt forms are used interchangeably. It is further noted,
that if the polyamino polycarboxylic derivative is added as a
water-soluble salt, the re~uired weight percentage range will
be higher than that of the acid, due to the presence of the
counter ion.
Therefore, in one embodiment, the present
invention can be described as a cleaning detergent
composition comprising (a) an alkali-metal carbonate builderî
and (b) a fabric encrustation prohibiting amount of a
polyamino poly-carboxylic acid or salt thereof.
Alkali-metal carbonate. The alkali metal
carbonate is the primary and may be the only builder material
of the composition of the present invention. As used herein,
the primary builder is defined as that builder which, in
total amount, has the higher capacity for hardness ions
(e.g., calcium (+2) and magnesium (+2)). The term
"co-builder" will refer to any remaining builder which has
the lesser capacity for such ions. Alkali metal carbonates,
310.102 -7-

2 ~
sesquicarbonates and bicarbonates are suitable primary
builders; however, the pre~erred builders are sodium and/or
potassium carbonates. A building effective amount of
carbonate is present in the compositions herein, which is
defined as that amount of alkali metal carbonates, as the
5 primary builder, which would precipitate in the presence of
hardness ions, in solution, during a wash period at ~0C and
250 ppm hardness. Such precipitation is determined by an
increase in solution turbidity as indicated by an abrupt
change in percent transmittance versus time defined
hereinafter. Generally, in terms of weight percent, and
assuming 68 liters of wash water and about 100 g of
composition, at least about 20 to about 80 percent,
preferably about 30 to about 70 percent, most preferably 50
percent carbonate is employed. As used herein, unless
otherwise stated, all percentages are weight percentages of
actives of the total composition. Higher levels of carbonate
will function, however, at levels greater than about 80
percent there is insufficient room for the other ingredients
which contribute to the overall effectiveness of the
composition. The carbonate acts as the builder to remove
divalent metal ions such as calcium, and additionally
provides alkalinity and aids in soil removal. At the high
levels disclosed herein, the alkali metal carbonate provides
good cleaning performance and in situations requiring a high
pH, such as oily soils, the carbonate builder may be superior
to other builders.
PolYamino Polvcarboxvli_ Acid Encrustation Preventative
Svstem
T h e p r e v e n t at i v e sy s t e m c o mp r is e s
substoichiometric levels of a polyamino polycarboxylic acid
or water-soluble salt thereof (hereinafter referred to as
"PAPCA"), which act to inhibit and prevent fabric
encrustation. For purposes herein, substoichiometric levels
of the polyamino polycarboxylic acid are defined to mean
levels which are insufficient to prevent the precipitation of
calcium and magnesium carbonate by sequestering water
310.102 -8-

hardness ions. For example, such levels generally comprise
less than about 30 percent, more preferably less than about
20 percent, of the total building capacity.
` By the term "polyamino polycarboxylic acid" it i.s
meant a compound having at least 2 amino groups and at least
2 carboxyl groups therein. The polyamino polycarboxylic acid
compounds of this invention relate to the following general
formula
R1\ /R3
N-M-N
R2 / \ R4
wherein M is selected from the group consisting of:
OH / H3
(1) -CH2CHCH2; ~2) -CH-CH2-; (3) -CH2CH2-;
(4) -CH2CH2OCH2CH2OCH2CH2-; and
/CH2COH Oj
(5) -CH2CH2N\ ~ CH2COH ;
CH2CH2--
CH2CH2-
and water soluble salts thereof; and where R1, R2, R3 and R4
are selected from the group consisting of -(CH2)nOH,
-CH2COOH, and -H wherein n is 1, 2 or 3; provided that when
M is (1), (2), (3) or (4) then at least three of R1, R2, R3
and R4 are -CH2COOH; and further provided that when M is
(5) at least R1 and R2 or R3 and R4 are each -CH2COOH,
individually.
The following are representative compounds of this
invention:
O O
HO~CH ~ OH / CH2~OH
Compound 1 / CH2CHCH2N
HOCCH2 CH2C:oH
0 o
1,3-Diamino 2-hydroxypropane N,N,N',N'-tetraacetic acid
310.102 -9-

1l fi
HOCCH2 CH3 / C~2CH
Compound 2 fNCHCH2N
HOCCH2 CH2COH
o o
1,2-Diaminopropane N/N,N',N'-tetraacetic acid
0 1~
HOCCH2 ~CH2COX
Compound 3 NCH2CH2N\
HOCCH2 lo
o
Ethylenediamine tetraacetic acid (EDTA)
HCH2CH2 ~ ~CH2COH
Compound 4 ~NCH2CH2N~
HOCCH2 CH21CIOH
O O
N(2-hydroxyethyl)ethylenediamine N,N,N'-triacetic acid
O o
ii iT
HOCCH2 ~ /CH2COH
Compound 5 /NCH2CH2N
H H
Ethylenediamine N,N'-diacetic acid
1l 1l R
HOCCH2 ~ IH2CH CH2COH
Compound 6 NCH2CH2NCH2cH2lcH2cH2N\
HOIClCH2 CH2COH CH21COH
O O O
Triethylenetetramine hexaacetic acid
310.102 -10-

2~4~ ~
1l - ~c
HOCCH2 / CH2 OH
Compound 7 NCH2cH2OcH2cH2oc~2cH2 ~
HOCCH2 CH2jCOH
o
Ethylene bis(oxyethylene nitrilo) tetraacetic acid
In a second embodiment, the cleaning composition
comprises a detergent composition including:
(a) an alkali-metal carbonate builder;
(b) an encrustation prevention system comprising
substoichiometric levels of polyamino
polycarboxylic acid or water-solub~e salts
thereof; and
(c) a surfactant.
Components (a) and (b) are as described previously
with respect to the first embodiment. Component (c) is
further described below.
Surfactant
A myriad of surfactants are known to be suitable
for laundry applications, including anionic, cationic,
non-ionic and amphoteric surfactants. Preferred surfactants
are anionic, nonionic and mixtures thereof, and if added are
present in a cleaning-effective amount. Preferred anionics
are selected from surfactants such as alkali metal alkyl
sulfates, primary and secondary alkane sulfonates, linear
alkyl benzene sulfonates, alkyl ether sulfates, and mixtures
thereof. These anionic surfactants will preferably have
alkyl chain groups averaging about 8 to 18 carbon atoms. The
preferred anionic surfactant is a LAS having an alkyl group
averaging 8 to 18 carbons. Commercial sources of such
surfactants are the Stephan Chemical Company (Northfield, IL)
and the vista Chemical Company (Houston, TX). An
additionally preferred anionic surfactant, principally for
its cleaning effectiveness, is a secondary alkane sulfonate.
310.102

2 ~ f ~!:
An example of a particularly preferred secondary alkane
sulfonate is HOSTAPUR SAS, a trade marked product
manufactured by Farbwerke Hoechst A.G. (Frankfurt, West
Germany~.
It is most preferred to ir.clude with the anionic
surfactant at least one nonionic, especially C1_4
alkoxylated aliphatic alcohols and Cl_4 alkoxylated alkyl
phenols. Particularly preferred are ethoxylated/propoxylated
C8_14 alcohol5. There should be at least about three
alkoxy groups per alcohol, preferably at least about nine.
Examples of preferred ethoxylated/propoxylated aliphatic
alcohols are BA5F Corporation's (Parsippany, NJ) trademarked
INDUSTROL, and PLURAFAC. Certain C1_4 alkylene oxide
copolymers such as ethylene oxide/propylene oxide copolymers
are also preferred as surfactants. These are exemplified by
BASF's trademarked PLURONIC series. Other suitable nonionic
surfactants are polyethoxylated alcohols manufactured and
marketed by the Shell Chemical Company (Houston, TX) under
the trademark NEODOL. Examples of preferred NEODOLS are
NEODOL 25-7 which is a mixture of 12 to 15 carbon chain
length alcohols with about 7 ethylene oxide groups per
molecule, NEODOL 23-65, a C12_13 mixture with about 6.5
moles of ethylene oxide, and NEODOL 25-9, a C12_15 mixture
with about 9 moles of ethylene oxide. Also useful are a
trimethyl nonyl polyethylene glycol ether, manufactured and
marketed by Union Carbide Corporation under the trademark
TERGITOL TMN-6, and an octyl phenoxy polyethoxy ethanol sold
by Rohm and Haas (Philadelphia, PA) under the trademark
TRITON X-114. Total surfactant content is preferably from 1%
to about 20%, more preferably from about 2% to 15%.
In a third embodiment, the present invention
comprises a dry, granular laundry detergent composition
comprising:
(a) an alkali-metal carbonate builder;
(b) a polyamino polycarboxylic acid or a water-
insoluble salt thereof as encrustation inhibitor system;
310.102 -12-

2 ~ J 1
(c) a surfactant;
(d) a bleach;
(e) an alkali-metal silicate;
(f) a filler; and
(g) laundry adjuncts.
Elements (a), (b) and (c) are as described in the first and
second embodiments. Elements (d) through (g) are further
described hereinbelow.
Bleach
Preferred peroxygen bleaches are available in
solid form and include sodium percarbonate, sodium perborate,
sodium phosphate peroxyhydrate, potassium permonosulfates and
metal peroxides. Bleach activators, also known as peracid
precursors, can be included with the peroxygen compounds.
Examples of activators include tetraacetyl ethylenediamine
(TAED), nonanoyloxy benzene-sulfonate (NOBS), and
nonanoylglycolate phenol sulfonate tNOGPS). NOBS and TAED
axe disclosed, for example, in U.S. 4,417,934, Chung et al.,
and NOGPS is disclosed, for example, in U.S. 4,778,618, Fong
et al., the disclosures of which are incorporated herein by
reference. Peracid bleaches (including monoperacids and
diperacids) may be advantageous in terms of bleaching
performance. Suitable peracid bleaching species include
C8_12 alkyl peracids, especially perazelaic and
diperazelaic acids, diperoxydodecanedioic acid (DPDDA), and
alkyl monoperoxysuccinic acid. Peracid bleaching species,
and a method for their production, are described in U.S.
4,337,213 to Marynowski et al., the disclosure of which is
incorporated herein by reference. The bleach is present in
an amount sufficient to provide effective bleaching, a.g.,
from about 0% to 10% by weight active, more preferably from
about 0.05% to 5% by weight active depending on the bleaching
species chosen.
Also, chlorine bleach could be used either added
preformed suspended on a substrate, mitigated or generated
in situ.
310.102 -13-

Alkali-metal Sil ate
An alkali-metal silicate can be included to
provide alkalinity and corrosion resistance. Preferred is
one having the formula:
M20(siO2~n
where M represents an alkali-metal and n is between about 1
and 4. Preferred alkali-metal silicates are sodium,
potassium and lithium silicates, with sodium silicate being
the most preferred, and with a preferr~d n value of 2.0-2.4.
A most preferred maximum value for n is about 3.2 in order to
minimize insoluble silicates during storage. It is further
preferred that at least about 10% of the total silicates have
an n value of greater than about 1.6 to impart suitable
anti-corrosive properties. Examples of other suitable
silicates include sodium or potassium orthosilicates and
metasilicates. As used hereinafter, the term "silicate" will
be taken to mean any of these alkali-metal silicates,
individually or combined.
Mixtures of any of the foregoing alkali-metal
silicates are also suitable. The alkali-metal silicate is
present in an amount of from about 0% to 10%, preferably
about 2~ to 5%. A minimum of about 1~ silicate is preferred
to provide adequate corrosion resistance. A commercially
available sodium silicates is sold by the Philadelphia Quartz
Corporation (Valley Forge, PA) under the trademarks RU (as a
47% solution~ ancl D (as a 44.1% solution). In addition to
their anti-corrosive effects, the silicates provide
alkalinity and serve as processing and granulating aids to
increase particle size of the agglomerates. Sodium silicates
also aid in cleaning, especially on oil and grease stains.
Filler
The filler is preferably a salt such as sodium
chloride, nitrate or sulfate, and is used to adjust the
composition density to achieve desired physical
characteristics, e.g., grain size and flowability. Depending
on the filler and the process used, the filler can also
310.102 -14-

2 ~
provide surface area for loading of actives. The filler
material additionally assists in solubility under cold water
washing conditions. Sodium chloride is preferred due to its
low cost and availability. However, other materials, such as
puffed borax, bentonite clays and inorganic salts su~h as
sodium or potassium sulfate, chloride, bromide, nitrate, and
borate, and organic materials like sugars may also be
suitahle. Some water may be deliberately added as a filler.
Gerlerally, a~out 0-30% filler will be present, preferably
about 5-25%.
Co-Builder
Optionally, any non-phosphate builder material
known in the art to be compatible with the high carbonate
formulation herein may be included as a co-builder selected
from the group consisting of silicates, citrates, alkali
metal carbonates, polymeric polycarboxylic acids such as
polyacrylates and maleic anhydride based co-polymers,
zeolites, salts of ethylene diamine, tetraacetic acid and
sodium nitrilotriacetate. Silicates at levels above about
10%, and citrates may be added as co-builders. If added, the
co-builder should comprise no more than about 30~ of the
total weight of the composition, and preferably no more than
about 20%. Zeolites are preferred as optional co-builders
since they perform well when used in a non-encrustation
promoting amount. A non-encrustation promoting amount is
that amount which will not contribute to or encourage the
encrustation formation when present in a detergent
formulation and in the presence of water harness ions.
Zeolite A is available, for example, from the PQ
Corp., Valley Forge, PA, under the trademark VALFOR 100.
Zeolite A typically includes about 21% moisture.
Adlun_ts
While the alkali-metal carbonate is generally
sufficient to ~eep the wash pH ranye within the desired
limits, it may be desirable to adjust the pH of the wash
310.102 -15-

2~ ,3 -
water by including an electrolyte/buffer. Generally, these
are alkali metal inorganic acid salts, hydroxides or oxides.
It may also be suitable to use such materials as aluminates
and organic materials, such as gluconate~, citrates,
succinates, maleates, and their alkali metal salts. The wash
pH range should be maintained between about 8.0 to 13.0, more
preferably about 9.0 to 12Ø If an electrolyte/buffer is
needed, sodium hydroxide is preferred, as it does not
interact adversely with any other ingredients and is very
cost effective. The amount of electrolyte/buffer added
solely for purposes of buffering can vary from about 0% to
10%.
In the standard composition, minor additions can
be included in the present invention. These include dyes,
such as Monastral blue and anthraquinone dyes (such as those
described in Zielske, U.S. 4,661,293 and U.S. 4,746,461).
Pigments, which are also suitable colorants, can be selected,
without limitation, from titanium dioxide, ultramarine blue
(see also, Chang et al~, U.S. 4,708,816), and colored
aluminosilicates. Fluorescent whitening agents are other
desirable adjuncts. These include the stilbene, styrene, and
naphthalene derivatives, which upon being impinged by
ultraviolet light, emit or fluorescent light in a visible
wavelength. These fluorescent whitener agents or brighteners
are useful for improving the appearance of fabrics which have
become dingy through repeated soilings and washings.
Preferred fluorescent whitener agents are TINOPAL 5BM-GX and
TINOPAL AMS, both from Ciba Geigy A.G., (Tom River, NJ) and
PHORWITE RKH, from Mobay Chemicals (Union, NJ).
Enzymes, particularly hydrolases such as lipases,
proteases and amylases, are useful additives in the
compositions herein. Suitable commercial sources include
ESPERASE and SAVINASE, both trademarked products of Novo
Industries (Danbury, CT). Generally, very low levels of
enzymes are needed, i.e. from about 0.1% to 1.0% by weight.
310.102 -16-

J~ Y'! ~
Fragrances are also desirable adjuncts in these
compositions. The total composition minors will range from
0% to about 5%. Anti-redeposition agents, such as
carboxymethyl-cellulose, are potentially desirable. Foam
boosters, such as appropriate anionic surfactants, may be
appropriate for inclusion herein. Also, in the case of
excess foaming resulting from _he use of certain surfactants,
anti-foaming agents, such as alkylated polysiloxanes, e.g.,
dimethylpolysiloxane, would be desirable. Water may be
present as free water or as water of hydration of the
inorganic salts such as sodium carbonate. The detergent
composition is prepared by a process which yields a dry,
free-flowing granular mixture, for example agglomeration or
spray drying. However, the compositions herein are not
limited to such forms, and may also be formulated in other
dry forms, such as tablets or beads, or may be formulated as
pastes, gels or liquids. An example formulation i5 shown
below as Example A.
EXAMPLE A
Inqredient Wt.% Active
Alkali metal carbonate 30-80
Surfactant 1-20
Bleaching agent 0-10
Alkali metal silicate 0-10
( sio2 /M20)
Filler
Polyamino polycarboxylic acid0.1-15
Composition Minors (enzymes, FWA's,
fragrances, etc.) 0-5
Co-builder 0-30
Water 0-15
EXPERIMENTAL
To assess effectiveness of the compositions herein
in reducing encrustation deposition, compounds of this
invention related to 1,3-diamino-2-hydroxypropane N,N,N',N'-
tetraacetic acid were tested for their effectiveness at
reducing encrustation in beaker studies. The compounds and
results are given in the following table.
310.102 -17-

2~ ~i7
Procedure
The turbidity measurement comprises measuring
percent transmittance using a dipping probe and colorimeter.
The probe is placed in deionized water and the percent
transmittance (%T.) is set to 100%. The detergent is
predissolved in 50 ml of water, then added to 950 ml of water
contaîning hardness ions as [Ca2+]/[Mg2+] = 3:1 molar
ratio. The final solution hardness was 300 ppm. Percent
transmittance is continuously plotted and measured vs time.
Results are presented as time before the onset of calcium
precipitation (tm) as determined by an abrupt change in the
slope of a graph of %T vs time. The longer the tm~ the
better the ability of the compound to prevent precipitation
of inorganic salts. Ideally, the tm should be longer than
the wash cycle, i.e., about 12-15 minutes in the case of
washing conditions in the United States. In practice, a tm
of greater than about 10, preferably 12 minutes, provides
commercially-acceptable results, as calcium precipitation
will still be inhibited to a degree sufficient to avoid
consumer preception thereof.
Simultaneously with the %T measurement, each
container of detergent sample has immersed therein a 3.5 x 4
inch 100~ cotton swatch, trimmed to l.00 grams. Slits
approximately 3 inches long were cut about 0.25 inch apart
for better circulation in the test container. After washing
for 10 minutes, the swatch is rinsed twice with 2 L deionized
water, and placed in a flask containing 25 ml of water and 10
ml each of 1.2M HCl to dissolve the CaCo3. Fifteen ml of a
standard NH40H hardness buffer and a Calmagite indicator
are then added and the solution is titrated with standardized
EDTA. Results are reported as mg CaC03 per gram of fabric
(swatch). Preferably, this value should be below about 4
mgtg, most preferably below about 2 mg/g.
310.102 -18-

2 ~ J ~
TABLE Ia
mg as CaCO3/
Cmpd. No. Concentration (ams/l)b tm om fabric
1 4.44 x 10 4M 0.143 20 1.55
2 5.0 x 10 4M 0.153 5.8 6.70
3 1.3 x 10 3M 0.380 4.5 5.75
4 5.0 x 10 4M 0.190 4.6 3.56
5.0 x 10 4M 0.088 2.415.30
6 5.0 x 10 4M 0.247 4.211.30
7 5.0 x 10 4M 0.190 9.7 4.85
Base Only - 4.512.90
a An agglomerated no-P detergent base was used which
contains 1.16 gm/l of Na2CO3 (corresponding to
78.6 gm/use Na2CO3 in 68 1 wash).
b gm/l are for the acid forms or the compounds.
Multicycle Wash Studv
To assess effectiveness of the compositions herein
in reducing encrustation deposition, 100% terry cloth
washcloths were washed for multiple cycles, under the given
wash conditions. A base detergent composition consisting of
61% Na2CO3, 11.0% surfactant, 5O0% sodium silicate and
5.0% sodium perborate were used. The polyamino
polycarboxylic acid compound was added to the base
composition in the amounts indicated in each case as
exemplified in Table II. About 3/4 cup (125 g/use) of
detergent and about 68 L of wash water was used for each
washload.
310.102 -19-

TABLE II
Multicycle Wash Studies
Wt. % Ash/5 CYcles/Cotton Washclothsb
Treatmenta _ 35C/100 ppm50C/200 ~pm
Base + 7.5 g Acrysol 0.4 4.7
LMW45N
4500 MW polyacrylic acid
Base + 4.44 x 10 4M 0.7 1.0
(9.72gm) 1,3-diamino-2-hydroxy-
propane N,N,N',N'-tetraacetic acid
a Multicycle wash studies were done with an agglomerated
detergent base containing 61 gm/use Na2C03. All
studies were done with 3:1 Ca/Mg molar concentration
water hardness. Concentrations are on an "actives"
basis.
b Ash is defined as the residue remaining after pyrolysis
of 950C in oxygen. Values are expressed at weight
percent.
Table II shows that substoichiometric levels of the
instant encrustation preventative system utilizing a
polyamino polycarboxylic acid yielded less calcium residue
(as ash) than the base detergent composition. With the
observed results for the inhibition of calcium carbonate
deposition, polyamino polycarboxylic acid could be a direct
replacement for polyacrylate which is known for its
anti-precipitation nature. Furthermore, since the polyamino
polycarboxylic acids described within are non-polymeric, they
should be more biodegradable than polyacrylic acid.
While this invention has been described and
illustrated with specific examples and descriptions, it is
understood that the invention is not to be limited to the
exact details of operation or exact components shown and
described herein, as obvious modifications and equivalents
will be apparent to those skilled in the art to which this
invention pertains. Therefore, the invention is to be
limited only by the scope within the claims appended hereto.
310.102 -20-