Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
~3~
The present invention relates, in general, to bleachin~ detergent com-
positions containing as a bleaching agent a peroxygen compound in combination
with an organic activator therefor, and the application of such compositions
to laundering operations. More particularly, the present invention relates
to granular bleaching detergent compositions which provide enhanced bleaching
performance concomitant with a significant improvement in the stability of the
peroxyacid bleaching species in the wash solution.
Bleaching co~positions which release active oxygen in the wash solution
are extensively described in the prior art and commonly used in laundering
operations. In general, such bleaching compositions contain peroxygen com-
pounds, such as, perborates, percarbonates, perphosphates and the like which
promote the bleaching activity by forming hydrogen peroxide in aqueous solu-
tion. A major drawback attendant to the use of such peroxygen compounds is
that they are not op~imally effective at the relatively low washing temper-
atures employed in most household washing machines in the ~nited States, i.e.,
temperatures in the range of 80 to 130~F. By way of comparison, European
wash temperatures are generally substantially higher extending over a range,
typically, from 90 to 200F. However, even in Europe snd those other countries
which generally presently employ near boiling washing temperatures, there is a
treDd towards lower temperature laundering.
In an effort to enhance the bleaching activity of peroxygen bleaches, the
prior art has employed materials called activators in combination with the per-
oxygen compound. It is generally believed that the interaction of the peroxygen
compound and the activator results in the formation of a peroxyacid which is a
more active bleaching species than hydrogen peroxide st lower temperatures.
2--
~L3~2~
Numerous compounds have been proposed in the art as activators for peroxygen
bleaches among which are included carboxylic acid anhydrides such as those
disclosed in U.S. Patent Nos. 3,298,775; 3,338,839; and 3,532,634; carboxylic
esters such as those disclosed in U.S. Patent No. 2,995,905; N-acyl compounds
such as those described in U.S. Patent Nos. 3,912,648 and 3,919,102; cyano-
amines such as described in U.S. Patent No. 4,199,466; and acyl sulfoamides
such as disclosed in U.S. Patent No. 3,245,913.
The formation and stability of the peroxyacid bleaching species in bleach
systems containing a peroxygen compound and an organic activator has been rec-
ognized as a problem in the prior art. U.S. Patent No. 4,255,452 to Leigh,
for example, specifically addresses itself to the problem of avoiding the re-
action of peroxyacid with peroxygen compound to form what the patent charac-
terizes as "useless products, viz. the corresponding carboxylic acid, molecular
oxygen and water". The patent states that such side-reaction is "doubly de-
leterious since peracid and percompound. . . are destroyed simultaneously."
The patentee thereafter describes certain polyphosphonic acid compounds as
chelating agents which are said to inhibit the above-described peroxyacid-
consuming side reaction and provide an improved bleaching effect. In contrast
with the use of these chelating agents, the patentee states that other more
commonly known chelating agents, such as, ethylene diamine tetraacetic acid
(EDTA) and nitrilotriacetic acid (NTA) are substantially ineffective and do
not provide improved bleaching effects. Accordingly, a disadvantage of the
bleaching compositions of the Leigh patent is that they necessarily preclude
the use of conventional sequestrants, many of which are less expensive and
more readily available than the disclosed polyphosphonic acid compounds.
The influence of silicates on the decomposition of peroxyacid in the wash
and/or bleaching solution has heretofore gone unrecognized in the art. U.S.
Patent Nos. 3,860,391 and 4,292,57$ disclose that silicates are conventionally
employed as additives to peroxide-containing bleaching solu~ions for the purpose
~L3~ ~
.
of stabilizing peroxide compounds therein. However, the patentees n`ote the fact
that the use of silicates in such bleaching solutions may create other problems
in the bleaching operations, such as, the formation of silicate precipitates
which deposit on the bleached goods. Consequently, the patents are directed
to processes for bleaching cellulose fiber with silicate-free bleaching solu-
tions in which peroxide stability is enhanced with compounds other than sili-
cates.
~ uropean Patent Publication No. 0,028,432, published May 13, 1981, discloses
a granular laundry composition containing, among other things, a water-insoluble
silicate and an organic activator compound for a peroxygen bleach. The pH char-
acteristics of such laundry composition are said to be critical; specifically,
the pH in a 2% aqueous dispersion being from 2 to 9, and preferably from 4 to 7.
At page 7 of the Publication there are described certain polyphosphonic acid
compounds as being highly preferred components of the composition, the publica-
tion stating in this regard that the polyphosphonates "have been found to be
uniquely effective in stabilizing organic peroxyacids against the generally
deleterious effect of water-insoluble silicates, especially those belonging to
the zeolite and kaolin classes". The nature of such "deleterious effect" is
not specified. At page 38 of the Publication granular laundry compositions are
disclosed in Examples VIII to X which do not contain sodium silicate, all of
such compositions being shown to contain Dequest*2041 (ethylenediamine tetra-
methylene phosphonic acid). The compositions of the aforementioned Examples
also contain a peroxygen compound activator which is incorporated into agglomer-
ate particles consisting of said activator, a water-insoluble silicate compound
and a nonionic surfactant.
Accordingly, the art has heretofore failed to appreciate or suggest the im-
proved bleaching performance which can be achieved with particulate bleaching
detergent compositions containing a peroxyacid compound when such compositions
are characterized by the absence of water-soluble silicate compounds.
*Trade Mark
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13~ 62301-1322
The present invention provides a bleaching detergent
composition comprising:
(a) from about 1 to about 50%, by weight, of a hleaching
agent eomprising a peroxyacid compound or a water-soluble salt
thereof,
(b) from about 5 to about 50%, by weight, of a detergent
surface active agent selected from the group consisting of
anionic, cationic, monionic, ampholytic and zwitterionic
detergents;
(c) from about 1 to about 60~, by weight, of a detergent
builder salts;
(d) from about 0.1 to about 10%, by weightr of a
sequestering agent; and
(e) the balance comprising water and optionally a filler
salt; said bleaching detergent composition being substantially
free of (i) water-soluble silicate compounds; (ii) organic
activators for peroxygen compounds and (iii) agglomerate
particles which essentially comprise a mixture of an activator,
a water-insoluble silicate compound and a nonionic surfactant.
In accordance with the process of the invention,
bleaching of stained andior soiled materials is effected by
contacting such materials with an aqueous solution of the
above-defined bleaching detergent composition.
The present invention is predicated on the discovery
that the undesired loss of peroxyacid in the aqueous wash
solution by reaction of peroxyacid with a peroxygen compound
(or more specifically, hydrogen peroxide formed from such
peroxygen compound) to ~orm molecular oxygen is markedly
reduced in bleaching systems which are substantially free of
water-soluble silicate compounds. Although the applicants do
not wish to be bound to any particular theory of operation it
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-. ., . ~
~3~ 62301-1322
is believed that the presence of water-soluble silicates in
bleaching systems containing a peroxyacid compound catalyzes
the aforementioned reaction of peroxyacid with hydrogen
peroxide which results in the loss of active oxygen from the
wash solution which would otherwise be available for bleaehing.
It has been recognized in the art that metal ions, such as, for
example, ions of iron and copper serve to catalyze the
decomposition of hydrogen peroxide and also the peroxyacid
reaction with hydrogen peroxide. However, with regard to such
metal ion catalysis, the applicants have surprisingly
discovered that conventional sequestrants, such as, ~DTA or
NTA, which the prior art has deemed to be ineffective for
inhibiting the aforementioned peroxyacid-consuming reaction
(see, ~or example, the statement in column 4 of U.S. Patent
4,225,452) can be incorporated into the compositions o~ the
present invention to stabilize the peroxyacid in solution.
The term "water-soluble silicate compounds" refers to
compounds such as sodium silicate which are substantially
soluble in aqueous laundering solutions and commonly present in
conventional bleaching detergent compositions, but are
substantially eliminated in the compositions of the present
invention. The present invention contemplates, however,
incorporating substantially water-insoluble silicates, most
notably, alumino-silicate materials such as clays and zeolites
into the bleaching detergent compositions described herein,
water-soluble silicate compounds being considered far more
detrimental to peroxyacid stability than water-insoluble
materials such as alumino-silicates.
In the invention, the bleaching compositions
described herein additionally contain a sequestering agent to
enhance the stability o~ the peroxyacid bleaching compound in
~3~ 62301-1322
solution by inhibitiny its reaction with hydrogen peroxide in
the presence of metal ions. The term "sequesteriny agent' as
used herein refers to organic compounds which are able to form
a complex with Cu2 ions su~h that the stability constant (pK)
of the complexation is equal to or greater than 6 in water at
25C at an ionic strength of 0.1 mole/liter, pK being
conventionally defined by the formula: pK = - log K wherein K
represents the equilibrium constant. Thus, for example, the pK
values for complexation of copper ion with NTA and EDTA at the
stated conditions are 12.7 and 1~.8, respectively. The term
"sequestering agent" is therefore used herein in a sufficiently
restrictlve sense to exclude inorganic compounds commonly used
in detergent formulations as builder salts. Especially useful
sequestering agents include EDTA, diethylene triamine
pentaacetic acid (DEPTA) and the various phosphonate
sequestrants marketed by Monsanto Company under the trademark
Dequest, e.g., Dequest 2000, 2006, 2041, 2051 and 2060.
In accordance with another embodiment of the
invention, the described blea~hing compositions are further
distinguished from certain water-soluble silicate free
compositions disclosed in the art by restricting the use of
sequestering agents in the present bleaching compositions to
those having a stability constant no greater than about 20 for
Cu2~ complex formation in water at 25~C and at an ionic
strength of 0.1 mole/liter. This limitation necessarily
precludes the presence of polyphosphonic acid compounds such as
Dequest 2041
:'
-6a-
13~.~Z~
(ethylene diamine tetramethylene phosphonic acid) and Dequest 2060 (diethy-
lene triamine pentamethylene phosphonic acid) in the bleaching compositions
of the invention, the aforementioned sequestrants having stability constants
above about 20. Accordingly, suitable sequestering agents for this embodiment
of the invention include the sodium salts of nitrilotriacetic acid (NTA); eth-
ylene diamine tetraacetic acid ~EDTA); ethylene diamine; tetramine, i.e.,
N-(CH2-CH2-NH2)3; bis(aminoethyl) glycolether-NNN'N'-tetraacetic acid (EGTA);
and N(CH2-P03H2)3~,which is marketed under thei:~radename ~equest 2000. EDTA
and the aforementioned Dequest 2000 are especially preferred for use in this
embodiment of the invention.
~ 3~ 62301~1322
The bleachiny detergent compositions of the invention
are substantially free of water-soluble silicate compounds and
are comprised of two essential components: (a) a bleaching
agent; and (b) a detergent surface active agent.
The bleaching agent useful in such compositions
comprises a water-soluble peroxyacid compound and/or a water-
soluhle saLt thereof. Peroxyacid compounds are characterized
by the following general formula:
O
H00 C - R Z
wherein R is an alkylene group containing from 1 to about 20
carbon atoms, or a phenylene group, and Z is one or more groups
selected from among hydrogen, halogen, alkyl, aryl and anionic
groups.
The organic peroxyacids and the salts thereof can
contain from about 1 to about 4, preferably 1 or 2, peroxy
groups and can be aliphatic or aromatic. The preferred
aliphatic peroxyacids include diperoxyazelaic acid,
diperoxydodecanedioic acid and monoperoxysuccinic acid. Among
the aromatic peroxyacid compounds useful herein,
monoperoxyphthalic acid (MPPA), particularly the magnesium salt
thereof, and diperoxyterephthalic acid are especially
preferred. A detailed description of the production of MPPA
and its magnesium salt is set forth on pages 7-10, inclusive,
of European Patent Publication 0,027,693, published April 29,
1981.
The bleaching agent may optionally also include a
peroxygen compound in addition to the peroxyacid ccmpound. The
useful peroxygen compounds include compounds that release
hydrogen peroxide in aqueous media, such as, alkali metal
perborates, e.g., sodium perborate and potassium perborate,
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~3~ 62301-1322
alkali metal perphosphates and alkali metal percarbonates. The
alkali metal perhorates are usually preferred because of their
commercial availability and relatively low cost. If desired,
an organic activator may be used in conjunction with such
peroxygen compound.
The bleaching detergent compositions of the invention
are characterized by being substantially free of (i) water-
soluble silicate compounds; (ii) organic activators for
peroxygen compounds; and (iii) agglomerate particles which are
essentially comprised of a mixture of three components; an
organic activator for the peroxygen compound; a water-insoluble
silicate compound, such as clay or zeolite; and a nonionic
surfactant, such mixture being at least 80~, by weight of the
agglomerate particles. The agglomerate particles which are
precluded for use herein are of the type formed in equipment
such as a pan granulator and serve to incorporate the bleach
activator in a matrix of materials as described in European
Patent Publication No. 0,028,432. In one particular embodiment
of the invention, the bleaching compositions are further
characterized by being substantially free of sequestering
agents having a stability constant for Cu2 complex formation
above about 20 in water at 25C and at an ionic strength of 0.1
mole/liter.
The water-insoluble silicate materials which may be
advantageously employed in the present bleaching compositions
are preferably aluminosilicates such as zeolites and smectite-
type clays. The crystalline types of zeolite which may be
employed include those described in "Zeolite Molecular Series"
by Donald W. Breclc, published in 1974 by John Wiley ~ Sons,
typical commercially available zeolites being listed in Table
9.6 at pages 747-749 of the text. Zeolite structures of type
~3~ 62301-13~2
are especially desirable and are extensively described in the
art; see, for example, page 133 of the aforementioned Breck
Text as well as U.S. Patent No. 2,882,2~3. The ~eolites are
particularly useful as builder salts in heavy duty detergent
; compositions.
The aforementioned smectite-type clays are three-
layer clays characterized by the ability of the layered
structure to increase its volume several-fold by swelliny or
expanding when in the presence of water to form a thixotropic
gelatinous substance. There are two classes of smectite-type
clays: in the first class, aluminum oxide is present in the
silicate crystal lattice; in the second class, magnesium oxide
is present in the silicate crystal lattice. Atom substitution
by iron, magnesium, sodium, potassium, calcium and the like can
occur within the crystal lattice of the smectite clays. It is
;; customary to distinguish 'oetween clays on the basis of their
predominant cation. For example, a sodium clay is one in which
the cation is predominantly sodium. With regard to the present
bleaching detergent compositions, aluminum silicates wherein
sodium is the preclominant cation are preferred, such as, for
example, bentonite clays. Among the bentonite clays, those
from Wyoming (generally referred to as western or Wyoming
bentonite) are especially preferred. Calcium and magnesium
clays are also useful albeit less preferred for purposes of
this invention.
Preferred swelling bentonites are sold under the
trademark Mineral Colloid, as industrial bentonites, by Benton
Clay Company, an affiliate of Georgia Kaolin Co. These
materials which are the sama as those formerly sold under the
trademark THIX0-JEL, are selectively mined and beneficiated
bentonites, and those considered to be most useful are
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62301-1322
available as Mineral Colloid No's. 101, etc. correspondiny to
THIX0-JELs No's. 1, 2, 3 and 4. Such materials have p~'s (6%
concentration in water) in the range of 8 to 9.4, maximum free
moisture contents of about 8% and specific gravities of about
2.6, and for the pulverized grade at least about 85% (and
preferably 100%) passes through a 200 mesh U.S. ~ieve Series
sieve. More preferable, the bentonite is one wherein
essentially all the particles (i.e., at least 90% thereof,
preferably over 95%) pass through a No. 325 sieve and most
preferably all the particles pass through such a sieve. The
swelling capacity of the bentonites in water is usually in the
range of 3 to 15 ml/gram, and its viscosity, at a 6%
concentration in water, is usually from about 8 to 30
centipoises.
In a particular preferred embodiment of the
invention, the carrier particles comprise agglomerates of
finely divided bentonite, of particle sizes less than No. 200
sieve, agglomerated to particles of sizes essentially in the
No's. 10-100 sieve range, of a bulk density in the range of 0.7
to 0.9 g/ml. and a moisture content of 8 to 13%. Such
agglomerates include about 1 to 5% of a binder or agglomerating
agent to assist in maintaining the integrity of the
agglomerates until they are added to water, in which it is
; intended that they disintegrate and disperse. A detailed
description of the method of preparation of such agglomerates
is set forth elsewhere.
-lOa-
~3~Z~
Instead of utilizing tne THIXO-JEL or Mineral Colloid bentonites one
may also employ equivalent competitive products, such as that sold by American
Colloid Company, Industrial Division, as General Purpose Bentonite Powder,
325 mesh, which has a minimum of 95% thereof finer than 325 mesh or 44 mi-
crons in diameter (wet particle size) and a minimum of 96% finer than 200
mesh or 74 microns diameter (dry particle size). Such a hydrous aluminum
silicate is comprised principally of montmorillonite (90% minimum), with
smaller proportions of feldspar, biotite and selenite. A typical analysis,
on an "anhydrous" basis, is 63.0% silica, 21.5% alumina, 3.3% of ferric iron
(as Fe203), 0.470 of ferrous iron (as FeO), 2.7% of magnesium (as MgO), 2.6% of
sodium and potassium {as Na20), 0.7% of calcium (as CaO), 5.6% of crystal
water (as H20) and 0.7% of trace elements.
Although the western bentonites are preferred it is also possible to
utilize synthetic bentonites, such as those which may be made by treating
Italian or similar bentonites containing relatively small proportions of
exchangeable monovalent metals (sodium and potassium) with alkaline materials,
such as sodium carbonate, to increase the cation exchange capacities of such
products~ It is considered that the Na20 content of the bentonite should be
at least abou~ 0.5%, preferably at least 1% and more preferably at least 2%
so that the clay will be satisfactorily swelling, with good softening and
dispersing properties in aqueous suspension. Preferred swelling bentonites
of the synthetic types described are sold under the trade marks Laviosa and
Winkelmann, e.g. 9 Laviosa AGB and Winkelmann G-13.
The compositions of the present invention contain one or more surface
active agents selected from the group of anionic, nonionic, cationic, ampho-
lytic and zwitterionic detergents.
~3~ 62301-1322
Among the anionic surface active agents useful in the
present invention are those surface active compounds which
contain an organic hydrophobic group containing from about ~ to
26 carbon atoms and preferably from about 10 to 18 carbon atoms
in their molecular structure and at least one water-solubili-
zing group selected from the group of sulfonate, sulfate, car-
boxylate, phosphonate and phosphate so as to form a water-
soluble detergent.
Examples of suitable anionic detergents include
soaps, such as, the water-soluble salts (e.g., the sodium,
potassium, ammonium and alkanol-ammonium salts) of higher fatty
acids or resin salts containing from about 8 to 20 carbon atoms
and preferably 10 to 18 carbon atoms. Suitable fatty acids can
be obtained from oils and waxes of animal or vegetable origin,
for example, tallow, grease, coconut oil and mixtures thereof.
Particularly useful are the sodium and potassium salts of the
fatty acid mixtures derived from coconut oil and tallow, for
example, sodium coconut soap and potassium tallow soap.
The anionic class of detergents also includes the
water-soluble sulfated and sulfonated detergents having an
alkyl radical containing from about 8 to 26, and preferably
from about 12 to 22 carbon atoms. (The term "alkyl" includes
the alkyl portion of the higher acyl radicals). Examples of
the sulfonated anionic detergents are the higher alkyl mono-
nuclear aromatic sulfonates such as the higher alkyl benzene
sulfonates containing from about 10 to 16 carbon atoms in the
higher alkyl group in a straight or branched chain, such as,
for example, the sodium, potassium and ammonium salts of higher
alkyl benzene sulfonates, higher alkyl toluene sulfonates
X - 12 -
62301-1322
~L3~
and higher alkyl phenol sulfonates.
Other suitable anionic detergents are the olefin
sulfonates including long chain alkene sulfonates, long chain
hydroxyalkane sulfonates or mixtures of alkene sulfonates and
hydroxyalkane sulfonates. The olefin sulfonate detergents may
be prepared in a conventional manner by the reaction of SO3
with long chain olefins containing from about 8 to 25, and
preferably from about 12 to 21
X
- 12a -
~3~
carbon atoms, such olefins having thc formula ~CII=CII~ wherein X is a
higher alkyl group of from abo~t 6 to 23 carbons and R1 is an alkyl group
containing from about 1 to 17 carbon atoms, or hydro~en to form a mixture
of sultones and alkene sulfonic acids which is then ~reated to convert the
sultones to sulfonates. Other examples of sulfate or sulfonate detergents
are paraffin sulfonates containing from about 10 to 20 carbon atoms, and
preferably from about 15 to 20 carbon atoms. The primary paraffin sulfo-
nates are made by reacting long chain alpha olefins and bisulfites. Para-
ffin sulfonates having the sulfonate group distributed along the paraffin
chain are shown in U.S. Nos. 2,503,280; 2,507,088; 3,260,741; 3,372,188
and German Patent No. 735,096.
Other suitable anionic detergents are sulfated ethoxylated higher fatty
alcohols of the formula R0(C2H40)mS03M, wherein R is a fatty alkyl of from
10 to 18 carbon atoms, m is from 2 to 6 (preferably having a value from
about 1/5 to 1/2 the number of carbon atoms in R) and ~ is a solubilizing
salt-forming cation, such as an alkali metal, ammonium, lower alkylamino or
lower alkanolamino, or a higher alkyl benzene sulfonate wherein the higher
alkyl is of 10 to 15 carbon atoms. The proportion of ethylene oxide in the
polyethoxylated higher alkanol sulfate is preferably 2 to 5 moles of ethy-
lene oxide groups per mole of anionic detergent, with three moles being most
preferred, especially when the higher alkanol is of 11 to 15 carbon atoms.
To maintain the desired hydrophile-lipophile balance, when the carbon atom
content of the alkyl chain is in the lower portion of the 10 to 18 carbon
atom range, the ethylene oxide content of the detergent may be reduced to
about two moles per mole whereas when the higher alkanol is of 16 to 18 car-
bon atoms in the higher part of the range, the numbcr of ethylene oxide groups
may be increased to 4 or 5 and in some cases to as high as 8 or 9. Similarly,
the salt-forming cation may be altered to obtain the best solubility. It may
be any suitably solubilizing metal or radical but will most frcqucntly bc
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~3i~ 62301-1322
alkali metal, e.g., sodium, or ammonium. If lower alkylamine
or alkanolamine groups are utilized the alkyls and alkanols
will usually contain from 1 to 4 carbon atoms and the amines
and alkanolamines may be mono-, di- and tri-substituted, as in
monoethanolamine, diisopropanolamine and trimethylamine. A
preferred polyethoxylated alcohol sulfate detergent is avail-
able from Shell Chemical Company and is marketed as Neodol*
25-3S.
The most highly preferred water-soluble anionic
detergent compounds are the ammonium and substituted ammonium
(such as mono, di and tri-ethanolamine), alkali metal (such as,
sodium and potassium) and alkaline earth metal (such as, cal-
cium and magnesium) salts of the higher alkyl benzene sulfo-
nates, olefin sulfonates and higher alkyl sulfates. Among the
above-listed anionics, the most preferred are the sodium linear
alkyl benzene sulfonates (LABS), and especially -those wherein
the alkyl group is a straight chain alkyl radical of 12 or 13
carbon atoms.
The nonionic synthetic organic detergents are charac-
teriæed by the presence of an organic hydrophobic group and an
organic hydrophilic group and are typically produced by the
condensation of an organic aliphatic or alkyl aromatic hydro-
phobic compound with ethylene oxide (hydrophilic in nature).
Practically any hydrophobic compound having a carboxy, hydroxy,
amido or amino group with a free hydrogen attached to the
ni-trogen can be condensed with ethylene oxide or with the poly-
hydration product thereof, polyethylene glycol, to form a non-
ionic detergent. The length of the hydrophilic or polyoxy-
ethylene chain can be readily adjusted to achieve the desired
*Trade-mark
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13~Z~ 62301-1322
balance between the hydrophobic and hydrophilic groups.
The nonionic detergent employed is preferably a poly-
lower alkoxylated higher alkanol wherein the alkanol is of 10
to 18 carbon atoms and wherein the number of moles of lower
alkylene oxide (of 2 or 3 carbon atoms) is from 3 to 12. Of
such materials it is preferred to employ those wherein the
higher alkanol is a higher fatty alcohol of 11 to 15 carbon
atoms and which contain from 5 to 9 lower alkoxy groups per
mole. Preferably, the lower alkoxy is ethoxy but in some
instances it may be desirably mixed with propoxy, the latter,
if present, usually being a minor (less than 50~) constituent.
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 mole, e.g., ~eodol~ 25-7 and Neodol 23-6.5, 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 moles of
ethylene oxide and the latter is a corresponding mixture where-
in the carbon atom content of the higher fatty alcohol is 12 to
13 and the number of ethylene oxide groups per mole averages
about 6.5. The higher alcohols are primary alkanols. Other
examples of such detergents include Tergitol~ 15-S-7 and
Tergitol 15-S-9, both of which are linear secondary alcohol
ethoxylates made by Union Carbide Corporation. The former is a
mixed ethoxylation product of an 11 to 15 carbon atom linear
secondary alkanol with seven moles of ethylene oxide and the
latter is a similar product but with nine moles of ethylene
oxide being reacted.
Also useful in the present compositions are the
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62301-1322
higher molecular weiyht nonionics, such as Neodol ~5-ll, which
are similar ethylene oxide condensation products of higher
fatty alcohols, the higher fat-ty alcohol being of 14 to 15
carbon atoms and the number of ethylene oxide groups per mole
being about ll. Such products are also made by Shell Chemical
Company.
Zwitterionic detergents such as the betaines and
sulfobetaines having the following formula are also useful:
7 N _ R4 ~ X - 0
wherein R is an alkyl group containing from about 8 to 18 car-
bon atoms,
X~ ~ 15a =
.~ nn~l R3 are each an alkyl or hydroxyalky] ~roup conlninillg al
1 to 4 carbon atoms, R~ is an alkylcne or hydroxyalkylene ~rou;) co~talni
1 to 4 carbon atoms, and X is C or S:~. The a]kyl groul) can ConLain onc
or more intermediate linkages such as amido, ether, or polyether linkages
or noniunctiona] su~stituents such ns hydloxy~ or hnlogen wllich do no~ s~
stantially affect the hydrophobic character of the group. Whcn X is C, the
detergent is called a betaine; and when X is S:O, the detergent is called
a sulfobetaine or sultaine.
Cationic surface active agents may also be employed. They comprise
surface active detergent compounds which contain an organic hydrophobic
group which forms part of a cation when the compound is dissolved in water,
and an anionic group. Typical cationic surface active agents are amine
and quaternary ammonium compounds.
Examples of suitable synthetic cationic detergents include: normal
primary amines o~ the ~ormula RNI~2 whercin R is an alkyl group containing
from about 12 to 15 atoms; diamines having the formula RNHC2H4NH2 wherein
R is an alkyl group containing from about 12 to 22 carbon atoms, such as
N-2-aminoethyl-sLearyl amine an~ N-2-aminoethyl myris~yl amine; amidc-
linked amines such as Lhosc having ~hc iormula KlC~NHC2~l4NH~ wh~rein Rl isan alkyl ~rouy conLainIn~ u~out 8 ~o 2~ car~on aLoms, ~uch us ~'-2-alliillo
ethylstearyl amide and N-amino ethylmyristyl amide; quacernary an)monium
compounds wherein typically one o~ the groups linkcd ~o the ni~rogcn
atom is an alkyl group containing about 8 to 22 carbon atoms and threc of
the groups linked to the nitrogen atom ar~ alkyl groups ~hich contain 1
to 3 carbon atoms, includin~ alkyl ~roups bearing inert substi~uents, such
as phenyl groups, and there is present an anion such 35 halogen, acetate,
methosulfate, etc. The alkyl group may con~ain intermediate linkages such
as amide which do not substantially afect the hydrophobic character o
--1~ . ,
~3~
the group, for example, stearyl ami~o propyl quaLernary alllmollum chioride
Typical qùaternary arn~onium deter~ents are e~hyl-dime~hyl-scearyl~ onium
chloride, benzyl-dimethyl-sLearyl ammonium chloride, trimethyl-scearyl
ammonium chloride, trimeLhyl-cetyl zmmonium ~romide, dimetllyl-ecllyl-lauryl
ammonium chloride, dimethyl-propyl-myristyl ammoniuln chloride, and ~he cor-
responding methosulfates and acetates
Ampholytic deter~ents are also suitable for the invencion ~mpholytic
~etergents are well known in the art and m~ny operable de~er~ents of chis
class are disclosed by Schwartz, Perry and Berch in the aforementioned
"SurLace Active A~ents and Deter~ents." ~xulnples of sui~able alllyho~eric
detergents inelude: alkyl betaiminodipropionates, RN(C2H4CO0~)2; alkyi
beta-amino propionates, KN~II)C2~14CO0~1; and long chain imidazole derivaLives
having the ~eneral formula:
N CH
Il 1 2
R-C N- C!
OH ~1~ COO,~
wherein in each of the above formulae R is an acyclic hydrophobic ~roup
containing from about 8 to 18 carbon atoms and ~ is a cation to neutralize
char~c oL Llle anion. spcciriC opcr;~l)lc an~ 0teric det~r~cllts illcludc
~he diso~iulll salL o~ undecylcycloillli~ liulll-e~hoxyethioloc acid-~-eLIIionic
aeid, dodecyl beca a]anine, and cl~e il-nCI' SL lt Or 2-Crillle~hyl~lllino lalll'iC acid.
'lhe ~le~ch~ de~el~ellL conll)osiciolls oL Lhe invell~ioll vy~iollally
conLain a de~er~ent builder Or Llle ~ype col"lllonly usell in deLCl'~CnC rOrn1UlnCiOlls.
Useful builders include any of ~he conventional inor~anic wa~er-soluble
,builder sal~s, such as, lor exalnl)le, W3~Cr-SO~ C ~al~s Or yllosl~llJCes,
pyrophosphates, orthophosphates, polypllosplla~cs, carbonates,
and the like. Or~anic buil~ers incluùe wn~er-solu~le ~hosyhonD-es, yoly-
~3~}Z~
phosl)honaCes, polyllydroxysul~ona~es, polyncetaLes, cal~ox~ es, l~olycar-
oxyla~cs, succinaLes Dnd CllC like.
Specific examples of inor~anic l)hos~h~te ~uil~ers inclu~le sodillm alld
potassium tripolyphosphates, pyrophosphates and hexameCaphosphates. The
or~anic polyphosphonates specifically incluùe, ~or example, the sodium
and potassium salts of ethane l-hydroxy-l,l-diphosphonic ~cid and tl~e sodium
and potassium salcs o~ ethane-1,1;2-triphosphonic acid. Ixalllples oL Lhese
and other phosphorous builder compounds are disclosed in U.S. Patent ~'os.
3y213,030; 3,422,021; 3,422,137 and 3,400,176. Pentasodium ~ripolyphos-
phate and ~etrasodium pyrophosphate are especially prelerred waLer-soluble
inor~anic builders.
Specific examples of non-phosphorous inorganic builders include water-
soluble inor~anic carbonate and bicarbonate sal~s. The alkali metal,
for example, sodium and potassium, carbonates and bicarbonates are parti-
cularly u~eful herein.
Water-sol~ble organic builders are a'so uselul. l:or example, ~I)e alkali
metal, ammonium and substituced ammonium polyace~ates, car~oxylates, poly-
carboxylates and polyhy~roxysulonates are useful builders for ~he compo-
sitions and processes o tlle lnvention. Specific examples o polyacetace and
polycarboxylate builders include sodiuln, potassium, lichium, amllloniuM an~
su~stituced ammonium salts of ethylene dianlinet~racetie acid, niLrilo~ri-
acetic acid, benzene polycarboxylic ~i.e. penta- and tetra-) acids, car~o~y-
methoxysuccinic acid and citric acid.
~ 'ater-issoluble builders may also be used, particularly, the comple~
silicates and more particularly, the complex sodiuln alumino silicaces such
as, zeolites, e.&., zeolite 4A, a t~pe o zeGlite molecule wherein the uni-
valen~ cation is sodium and the pore size is abou~ 4 An~s~roms. The prepar-
atioll o~ ~ucl~ tyye zeo~ite is descriued in I).S. P~tent 3,~lL,~03. The zeo-
lites may be amorphous or crysialline and have ~a~er ol hydra~ion as kno~n
. _ . .
in the nrt.
-18-
~3~ 3~
An inert, ~a~er-soluble filler salt is desirably included in the
launderin~ compOsitions of the invcntion. A prefcrred ~ r s.Jlt is an
alkali me~al sùlfate, such as, potassium or sodium sulfate, thc lattcr bein~
especially preferred.
VariouS adj~vants may be included in the laundry detergent compositions
of the invention. In general, these include perfumes; colorants, e.g., pi~-
ments and dyes; bleaches, such 2s, sodium perborate, antircdcposition a~cnts,
such as, alkali metal salts of carboxymethylcellulose; optical brighteners,
such as, anionic, cationic or nonionic brighteners; foam s~abili2ers, such
as alkanolamides, and the like, all of which are well-known in the fabric
washing art for use in detergent compositions. Flow promotin~ a~ents, commonly
referred to as flow aids, may also be employed to maintain the particulate
compositions as free-flowing beads or powder. Starch derivatives and speciai
clays are commercially availa~le as additives which enhance the flowabili~y
of otherwise tacky or pasty particulate compositions, two of slJcn clay
additives being presently marketed under the trade~a~ks "Satintone" and
"Microsil".
A preferred bleaching detergent composition in accordance with the in-
vention typically comprises (a) from about 2 to 50%, by weight, of a bleaching
agent comprising a peroxyacid compound and/or a water-soluble salt thereof;
(b) ~rom about 5 to 50%, by weight, of a detergent surface active agent;
(c) from about l to about 60%, by weight, of a deter8ent builder salt; and
(d) from about O.l to about 10%, by weight, of a sequestering agent; such com-
position being characterized by being substantially free of (i) water-soluble
silicate compounds; (ii) organic activators for peroxygen
compounds; and (iii) agglomerate particles which essentially
comprise an activator, a water-insoluble silicate compound
and a nonionic surfactant. The balance of the composition
will predominantly comprise water, filler salts, such as,
sodium sulfate, and minor additives selected from among the
various adjuvants described above.
The particulate bleaching detergent compositions of the invention are pre-
pared by admixing the bleaching agent and optional sequestering agent with the
~3~
spray-dried detergent composition, the latter being formulated so as to avoid
the use of water-soluble silicate compounds, most notably, sodium silicate.
The presence of very minor amounts of ~ater-soluble silicate compounds in the
final compositions, i.e., below about 0.5%, preferably below about 0.2~, and
most preferably no greater than about 0.1%, by weight, such as may occur with
the use of silicate-containing pigments or dyes, or upon contact of the aqueous
crutcher slurry with residual amounts of sodium silicate in the spray tower,
is contemplated by the present invention. I
The spray drying of a silica~e-free detergent formulation may result in
a relatively dusty granular product due to the absence of silicate as a binder
for the spray dried beads. However, alternative organic binder materials may
be employed, such as, for example, starch, carboxymethyl-cellulose and materi-
als comparable thereto. The strength of the spray dried beads may also be en-
hanced by maximizing the solids content of the silicate-free slurry in the
crutcher and/or by maintaining the inlet temperature of the hot air stream in
the spray tower as low as possible.
The bleaching agent can be mixed either directly with the spray dried
powder or the bleaching agent and optional sequestering agent can be separately
or collectively coated with coating material to prevent premature activation
of the bleaching agent. The coating process is conducted in accordance with pro-
cedures well known in the art. Suitable coating materials include compounds
such as magnesium sulfate, polyvinyl alcohol, lauric acid and its salts and the
like.
The bleaching detergent compositions of the invention are added to the
wash solution in an amount sufficient to provide from about 3 to about 100 parts
of active oxygen per million parts of solution, a concentra~ion of from about
5 to about 40 ppm being generally preferred.
The particulate bleaching detergent compositions described above may be
produced by such methods as spray-drying, dry-blending, or agglomeration of the
individual components.
_20-
-
~3~
EXAMPLE l
A preferred silicate-free bleaching detergent composition is comprised
of the following:
Component Wei~ht Percent
Sodium linear C10 - C13 6
alkyl benzene sulfonate
EthoxYlated Cl1 - C18
primary alcohol (11 moles EO per
mole alcohol)
Soap (sodium salt of C12 - C22 4
carboxylic acid)
Pentasodium tripolyphosphate (TPP) 32.0
EDTA 0.5
Monoperoxyphthalic acid (MPPA), 7
magnesium salt
Carboxymethyl cellulose 0.5
Optical brighteners, pigment and 0.4
perfume
Proteolytic enzymes 0.5
Sodium sulfate and water balance
` ~L3~ 3~
The foregoing product is produced by spray drying an aqueous slurry con-
taining 60%, by weight, of a mixture containing all of the above components
except the enzyme, perfume and monoperoxyphthalic acid (MPPA). The resultant
particulate spray dried product has a particle size in the range of 14 mesh
to 270 mesh, (U.S. Sieve Series). The spray dried product is then mixed in a
rotary drum with the appropriate amounts of MPPA of similar mesh size 9
enzyme and perfume to yieid a particulate product having a moisture of approx-
imately 14%, by weight.
The above-described product is used to wash soiled fabrics by hand-washing
as well as in an autsmatic washing machine, good laundering and bleaching per-
formance being obtained for both methods of laundering.
Other satisfactory products can be obtained by varying the concentrations
of the following principal components in the above-described composition as
follows:
Component Weight Percent
Alkyl benzene sulfonate 4-12
Ethoxylated alcohol 1-6
Soap 1-10
TPP 15-50
Enzymes 0.1-1
EDTA 0.1-2
MPPA 1-20
For highly concentrated heavy duty detergent powder, the alkyl benzene
sulfonate, TPP and the soap components in the above described composition may be
deleted, and the ethoxylated alcohol content may be increased to an upper
limit of 2070.
-22-
31 3~
EXAMPLE 2
Bleaching tests are carried out as described below comparing the bleach-
ing performance of a water-soluble silicate-free bleaching detergent composition
in accordance with the invention and a corresponding silicate-containing composi-
tion, the latter composition being comparable to the former in nearly all re-
spects except for the presence of a water-soluble silicate compound. The bleach-
ing agent employed is a mixture of monoperoxyphthalic acid salt and sodium per-
borate. The compositions are formulated by post-adding to a spray-dried parti-
culate detergent composition, granules of the H-48 bleaching composition (de-
scribed in the footnote of Table 1) to form the bleaching detergent compositions
A and B shown in Table 1 below. The numbers indicated in the Table represent
the percentage of each component, by weight, in the composition.
-23-
~3~
TABLE 1
Component Composition
A B
(Silicate-free? ~Silicate-containin~?
Sodium linear C10 - C13 6.00% 6.00%
alkyl benzene sulfonate
Ethoxylated Cll - C18 primary 3.50 3.50
alcohol ~11 moles EO per mole
alcohol)
Soap (Sodium salt of C12 - C22 2.50 2.50
carboxylic acid)
Sodium silicate (Na20:2Si02) ---- 9.00
Pentasodium tripolyphosphate (TPP) 35.00 35.00
Optical brightener (stilbene) 0.22 0.22
Sodium perborate tetrahydrate 3.00 3.00
H_48(1) 9.00 9.00
EDTA (Disodium salt) 1.00 1.00
Sodium sulfate 35.00 10.60
Water balance balaDce
(1) A bleaching composition sold by Interox Chemicals Limited, London, England,
containing about 65 wt. % magnesium monoperoxyphthalate, 11 wt. % magnesium
phthalate, balance H20.
. ~4_
~3~Zl~
TEST PROCEDURE
The active oxygen concentration in solution is determined as a function
of time for separate wash solutions containing compositions A and B, respect-
ively, using the following procedure:
One li~er of tap wster is introduced into a two liter beaker and then
heated to a constant temperature of 60C in a water bath. Ten grams of the
particular composition being tested (A or B) are added to the beaker (time = O)
with thorough mixing to form a uniform wash solution. After given periods of
time (3, 7, 13, 20, 30, 40 and 50 minutes), a 50 ml aliquot is withdrawn from
the wash solution and the total active oxygen concentration is determined by the
procedure set forth below.
Determination of Total Active O Concentration
- 2
The aforementioned 50 ml aliquot is poured into a 300 ml erlenmeyer flask
containing 15 ml of a sulfuric/molybdate mixture, the latter mixture having been
prepared in large-scale amounts by dissolving 0.18 grams of ammonium molybdate
in 750 ml of deionized water and then adding thereto 320 ml of H2S04 (about 36N)
with stirring. The solution in the erlenmeyer is thoroughly mixed and 5 ml of
a 10% KI solution in deionized water is then added thereto. The erlenmeyer is
sealed with a stopper, agitated and then allowed to stand in a dark place for
about seven minutes. The solution in the flask is then titrated with a solu-
tion of O.lN sodium thiosulfate in deionized water. The volume of thiosulfate
required in ml, is equal to the total active oxygen concentration, in millimole/
liter, in the wash solution. The tests results for the two compositions tested
are shown in Table 2 below.
_25_
"
~3~`2
TABLE 2
Total Active Oxy~en in Wash Solution (mmol/liter)
A E
Time (min.) (Silicate-free) (Silicate-containin~)
3 4.8 2.4
7 4,4 1.2
13 4.2 l.O
3.9 0.8
3-7 0.6
3.4 0.5
3.2 0.4
As shown in Table 2, the silicate-free composition A is significantly
more stable and is characterized by a far slower loss of active oxygen from
solution than the corresponding silicate-containing composition B.
26_
