CA1226503A - Bleaching and laundering composition free of water- soluble silicates - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
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An improved particulate bleaching detergent composition is provided comprising (a) a bleaching agent comprising an inorganic peroxygen compound in combination with an activator therefor; and (b) at least one surface active agent selected from the group consisting of anionic, cationic, nonionic, ampholytic and zwitterionic detergents; said bleaching detergent composition being substantially free of (i) water-soluble silicate compounds and (ii) agglomerate particles which essentially comprise said activator, a water-insoluble silicate compound and a nonionic surfactant

Description

~IEj5~3 The present invention relates, in general, to bleaching deter-gent compositions containing as a bleaching agent a per oxygen compound in combination with an organic activator therefore 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 compositions which release active oxygen in the west solution are extensively described in the prior art and commonly used in laundering operations. In general, such bleaching compositions contain per oxygen compounds, such as, perorates, per carbonates, perphospha~es and the like which promote the broaching activity by forming hydrogerl peroxide in aqueous solution. A major drawback attendant to the use of such pero~ygen compounds is that they are not optimally effective at the relatively logy washing temperatures employed in most household washing machines in the United States, isle temporize in the range of 80 to 130F. By way of comparison, European wash temperatures are generally substantially higher extending over a range, typically, from 90 to 200F. Ilowever, even in Europe and those other collators Lucia generally presently employ near boil-in washing temperatures, there it a trend towards lower temperature laundering.
In an effort to enhance the bleaching activity of per oxygen leaches, the prior art has employed materials called activators in combination with the per oxygen compound. it is generally believed that the interaction of the per oxygen compo~md allele the activator results yin the formation of a peroxyacid which is a more active bleaching species the hydrogen peroxide at lowlier tcmperatllres.

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Numerous compounds have been proposed in the art as activators for per oxygen bleaches among which are included carboxylic acid anhyd}ides such as those disclosed in US. Patent No. 3,298,775; 3,338,839; and 3,532,634; carboxylic esters such as those disclosed in US. Patent No. 2,995,905; Nuzzle compounds such as those described in US. Patent Nos. 3,912,648 and 3j919,102; cyan-amine such as described in US. Patent No. 4,1~9,466; and azalea sulfonamides such as disclosed in US. Patent No. 3,245,913.
The formation and stability of the peroxyacid bleaching species in bleach systems containing a per oxygen compound and an organic activator has been fee-ognized as a problem in the prior art. US. Patent No. 4,255,452 to Leigh, for example, specifically addresses itself to the problem of avoiding the no-action of peroxyacid with per oxygen compound to form what the patent kirk-torsos as "useless products, via. the corresponding carboxylic acid, molecular oxygen and water". The patent states that such side-reaction is "doubly de-lotteries since pursued and per compound. . . are destroyed simultaneously."
The patentee thereafter describes certain polyphosphonic acid compounds as chelating agents which are said to inhibit the above-described peroxyacid-ConSumiTIg side reaction and provide an improved bleaching effect. In contrast with the use of these chelating agents, the pun states that other more commonly known chelating agents, such as, ethylene Damon tetraacetic acid (ETA) and ni~rilotriacetic acid (NAT) 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. US.
Potent Nos. 3,86013~1 sod 4,292,575 disclose that silicates are conventionally employed as additives to peroxide-containing bleaching solutions for thy purpose -of stabilizing peroxide compounds therein. However, the patentees note 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 solutions in which peroxide stability is enhanced with compounds other than silicates.
European Patent Publication No. 0,028~432, published slay 13, l~8l~
discloses a granular laundry composition containing, among other things, a lo water-insoluble silicate and an organic activator compound for a per oxygen bleach. The pal characteristics of such laundry composition are said to be critical; specifically, the pal in a 2% aqueous dispersion being from 2 to 9, and preferably frown 4 to 7. At page 7 of the Publication there are describe Ed certain polyphosphonic acid compounds as being highly preferred compo~mds of the composition, the publication staying in this regard that the polyp phosphonates "have been found to be uniquely effective in stabilizing or-genie peroxyacids against the generally deleterious effect of water-insoluble silicates, especially those belonging to the elite and kaolin classes".
Ike nature of such "deleterious effect" is not specified. At page 38 of the Publication granular laundry compositions are disclosed in Examples VIII
to X weakly do not contain Sydney silicate, all of such compositions beillg shown to contain Request 2Q41 ~ethylenediamine tetramethylerle phosphoric acid). The compositions of the aforementioned Examples also contain a peroxygel~ compound activator which is incorporated irltO agglomerate particles consisting of said activator, a water-insoluble silicate compound and a non ionic surfactant.
The presort invention provides a particulate bleaching detergent composition comprising: aye a bleachil1g agerlt comprising n peroxygoll killed in combitlatioll with an activator thcret`or; hi (by lit loyalist on surface llCt:iVe Girl agent selected from the group of anionic, cat ionic, non ionic, ampholytic and zwitterionic detergents; said bleaching detergent composition being sub Stan-tidally free of (i) water-soluble silicate compounds and (ii) agglomerate par-tickles which essentially comprise said activator, a water-insoluble silicate compound and an non ionic surfactant.
In accordance with the process of the invention, bleaching of stained and/or soiled materials is effected by contacting such materials with an a-use solution of the above-defined bleaching detergent composition.
The present invention it predicated on the discovery that the undesired loss of peroxyacid in the aqueous wash solution by reaction of pursued with a p~roxygen compound or more specifically; hydrogen peroxide formed from such per oxygen compound) to form molecular oxygen is markedly reduced in bleaching systems which arc substantially free of water-soluble silicate compounds. Al-though the applicants do not wish to be Byrd to any particular theory of open-anion, it is believed that the presence of water-soluble silicates in peroxy~en compound/acti~ator bleach systems koalas the aforementioned reaction of per-oozed with hydrogen peroxide which results in the loss of active oxygen from the wash solution which would otherwise be available for bleaching. 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 resend to such petal ion catalysis, the applicants have surprisingly discovered that coven--tonal sequestrants, such as, ETA or NAT, which the prior art has deemed to be ineffective for inhibiting the aforementioned peroxyacid-consuming reaction (see, for example, the statement in column 4 of US. Patent 4,225,452~ can be incorporated into the compositions of the present invention to stabilize! the peroxyacid in solution.
The term "~ater-soluble silicate compounds" refers to compounds such as sodium silicate which are substantially soluble in aqueous laundering solutions and commonly present in conventional blacken detergent compositions, but are I

substantially eliminated in the compositions of Lowe present invention. The present invention contemplates, however, incorporating substantially water-insoluble silicates, most notably, alumino-silicate materials such as clays and zealots 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.
ID a preferred embodiment of the invention, the bleaching compositions described herein additionally contain a sequestering agent to enhance the stability of the peroxyacid bleaching compound in solution by inhibiting its reaction with hydrogen peroxide in the presence of metal ions. The term "so-questering agent" as used herein refers to organic compounds which are able to form a complex with Cut + ions such that the stability constant (pi) of the come plexation is equal to or greater than 6 in water at 2~C at an ionic strength of 0.1 mole/liter, pi being conventionally defined by the formula: pi = - log K wherein K represents the equilibrium constant. Thus, for example, the pi values for complexation of copper ion with NAT and ETA at the stated condo-lions are 12.7 and 18.8, respectively. The term "sequestering agent" is there-fore used herein in a sufficiently restrictive sense to exclude inorganic come pounds commonly used in detergent formulations as builder salts. Especially useful sequestering agents include ETA, diethylene thiamine pentaacetic acid DWIGHT) and the various phosphonate sequestrants marketed by Monsanto Company under the trademark Request, eye., Request 2000, 2006~ 2041, 2051 and 2060.
In accordance with another embodiment of the invention, the described bleaching compositions are further distinguished from certain water-soluble silicate free compositions disclosed in the art by restricting the use of so-questering agents in the present bleaching compositions to those having a stay ability constant no greater than about on for Cut+ complex formation in water at 25C and at an ionic strength of 0.1 mole/liter. This limitation necessary fly precludes the presence of yolyphosphorlic acid compounds such fly Dakota 2041 ~2~133 (ethylene Damon tetramethylene phosphoric acid and Request 2060 (depth-tone thiamine pentamethylene phosphoric 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 (NAT); elk-ylene Damon tetraacetic acid EDIT); ethylene Damon; tetramine, i.e., N~(CH2-CH2-NH2)3; bis(aminoethyl~ glycolether-NNN'N'-tetraacetic acid (ETA);
and N(CH2-P03H2)3.,which is marketed under thel~radename Request 2000. ETA
and eye aforementioned Request 2000 are especially preferred for use in this embodiment of the invention.

The bleaching detergent compositions of the invention are come prosaically of two essential components: (a) a bleaching agent; and (b) a detergellt surface active agent.
The bleaching agent useful in such compositions comprises a per-oxygen compound in combination with an organic activator therefore The per oxygen compounds useful in the present compositions include compounds that release hydrogen peroxide in aqueous media, such as, alkali metal perorates, e.g., sodium perorate and potassium perorate, alkali petal per phosphates and alkali metal percarbo~ates. The alkali metal perorates are usually preferred because of their commercial availability and relatively low cost.
Conventional activators such as those disclosed, for example, at Cole 4 of United States Patent 4,259,200 are suitable for use in conjunct lion with the aforementioned per oxygen compo~mds. The polyacylated amine are generally of special interest, tetraacetyl ethylene Damon TODD) in particular being a highly preferred activator. The TED is preferably present in the compositions of the invention in the form of "coated" granules which contain the TOED and a suitable carrier material such as a mixture of sodium and potassium triphosphate. Such coated TOED granules are conveniently pro-pare by mixing finely divided particles of sodium triphosphate and TOED and then spraying onto such mixture an azaleas solution of potassium triphosphate using suitable granulation equipment such as a rotating pall granulator. to typical method of preparation for this type of coated TOED is described in United States Patellt 4,283,302 to Fret, et at. Ike granules of TAO have a preferred particle size distribution as follows: 0-20% greater than 150 micrometers; 10-100~ greater than 100 em but less than 150 em; 0-50% less than 75 em; and 0-20% less than 50 my other particularly preferIecl par-tide size distribution is where the median pareiclc size of TAO its 160 irons, I 50'~ of the articles have a Seiko greaecr than 160 mackerels.

The aforementioned size distributions refer to the TOED present in the coated granules, and not to the coated granules themselves. The molar ratio of per oxygen compound to activator can vary widely depending upon the par-titular choice of per oxygen compound and activator. However, molar ratios of from about 0.5:1 to about 25:1 are generally suitable for providing satisfactory bleaching performance.
The bleaching agent may optionally also contain a peroxyacid compound in combination with the per oxygen compound and activator. Useful peroxyacid compounds include water-soluble peroxyacids and their water-soluble salts. The peroxyacids can be characterized by the following general formula:
o Lowe - C - R Z

wherein R is an alkaline group containing from 1 to about 20 carbon atolls, or a phenylene group, and Z is one or more groups selected front among hydrogen, halogen, alkyd, aureole, and anionic groups.
The organic peroxyacids and the salts thereof can contain from about 1 to about 4, preferably 1 or 2, porks groups can be allphatic or aromatic. The preferred aliphatic peroxyacids include diperoxyazelaic acid, ~diperoxydodecanedioic acid and monoperoYySuCCiniC acid. Among the aromatic peroxyacid compounds useful herein, monoperoxyphthalic acid (hlPPA), part-ocularly the magnesium salt thereof, end cliperoxyterephthalic acid art especially preferred. detailed description of the production of ~IPPA end its magnesium salt is set forth on pages 7-}0, inclusive, of European Patent Publication ~,027,G93, published April 29, 1981.
The bleaching detergent compositions of the inventioll are char-acterized by being substantially -tree of (i) ~nter-soluble silicate compounds and ~iiJ agglomerate particles which are esselltially comprised of a nli.Ytllre of three conlpollents: tile organic activator for the peroYygell cotlllound;
a water insolubly _ 9 silicate compound, such as clay ox elite; and a non ionic surfactant, such mixture being at least 80%9 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 ox the invention the bleaching compositions are further characterized by being substantially free of sequestering agents having a stability constant for Queue complex formation above about 20 in water at 25C and at an tonic strength of 0.1 mole/liter.
The water-insoluble silicate materials which may be advantageously employed in the present leaching compositions are preferably alumina-silicates such as zealots and smectlte type clays. The crystalline types of elite which may be employed include those described in "Zealot Molecular Series" by Dollald W. Brook, published in 1974 by John Wiley &
Sons typical commercially available zealots being listed in Table 9.6 at pages 747-749 of the text. Zealot structures of type A are especially desirable and are extensively described in the art; see, for example, page 133 of the aforementioned Brook Text a jell a US. Patent No. 2,882,243. The zeolitet; are particularly useful at builder salts in heavy duty detergent compositions.
The aforementioned smectite-type clays are three-layer clays ~haracterlzed by the ability of the layered structure to increase its volume several-fold by swelling or expanding when in the presence of water to form a thixotroplc gelatinous substance. There are two classes of s~cctitQ-type clays: in the first class, aluminum oxide 18 present in the silicate crystal lattice, in the second Claus magnesium oxide is present Lo the silicate crystal 1 Tokyo. Atop substitution by iron, magneslu~ sodium, potasgiu~, calcium and the like can occur within the crystal lattice of the sm~cCite clays. It it customary to distin~ul~h between clay on the Bessel of their predOmLllaht CfltiOIl. For Rx~lmpls~ a sodium clay it on In high the ctitlon 19 pr~dol~intlntIy sodium. With regard to the ~2Z1~5~3 present bleaching detergent compositions, aluminum silicates wherein sodium is the predominant cation are preferred, slush 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 linearly Killed, as industrial ben~onites, by Kenton Clay Company, an affiliate of Georgia Kaolin Co. These materials which are the same as those formerly sold under the trademark THIX0-JEL, are selectively mined and beneficiated bentonites, and those considered to be most useful are available US linearly Killed No's. loll etc. corresponding to THIX0-.JELs No's. 1, 2, 3 and 4.
Such materials have plies (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 US. Sieve Series sieve. lore preferable, the bentonite is one wherein essentially all the particles (i.e., it least 90% thereof, preferably over 95%) pass through a No. 32S sieve and most preferably all the particles pass through such a sieve. The swelling gape-city of the bentonites in water is usually in the range of 3 to 15 mllgram,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 essential-lye in the No's. 10-100 sieve range, of a bulk density in the range of 0.7 to 0.9 gel and a moisture content of 3 to 13~. Such agglomerates include about 1 to So of a hinder or agglomerating agent to assist in maintaining the integrity of tile agglomerates until they are added to water, in which it is intended thflt they disilltegrate and disperse.

, Instead of utilizing the THIXO-JEL or Mineral Killed bentonites one may also employ equivalent competitive products, such as that sold by American Killed Company, Industrial Division, as General Purpose Bentonite Powder, 325 mesh, which has a minimum of 95% thereof finer than 325 mesh or 44 mix crows in diameter (wet particle size) and a monomania 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 silent. A typical analysis, on an an hydrous basis, is 63.0% silica, 21.5% alumina, 3.3% of ferris iron (as Foe), 0.4% of ferrous iron (as Foe), 2.7% of magnesium (as MgQ), 2.6% of sodium and potassium (as Noah), 0.7% of calcium (as Coo), 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 Noah content of the bentonite should be at least about 0.5%, preferably at least I 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 ~entonites of the synthetic types described are sold under the trade names Levis and Winkelrllann, e.g., Lucy AGO and Winkelmann G-13.
The composition of the present invention contain one or more surface active agents selected from the group of anlonicJ non ionic, cat ionic, amp ho-lyric and ~witterionic detergents.

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Among the anionic surface active agents useful in the present invention are those surface active compounds which con-lain an organic hydrophobic group containing from about 8 to I
carbon atoms and preferably from about 10 to 18 carbon atoms in their molecular structure and at least one water-solubilizing group selected from the group of sulfonate, sulfate, carboxylate, phosphonate and phosphate so as to form a water soluble deter-gent.
Examples of suitable anionic detergents include soaps, such as, the water-soluble salts (e.g., the sodium, potassium, ammonium and alkanolammonium salts) of higher fatty acids or resin salts containing from about 8 to 2G carbon atoms and pro--fireball 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 sul.fonated detergents having an alkyd radical containing from about 8 to 26, and preferably from about 12 to 22 carbon atoms. (The term "alkyd" includes the alkyd portion of the higher azalea radicals. Examples of the cellophane-axed anionic detergents are the higher alkyd mononuclear art-matte sulfonates such as the higher alkyd Bunyan sulfonates containing from about 10 to 16 carbon atoms in the higher alkyd group in a straight or branched chain, such as, for example, thy sodium, potassium and ammonoium salts of higher alkyd Bunyan sulfonates, hither alkyd Tulane sulfonates and hither alkyd phenol sulfon~tes.

I
'I' Other suitable anionic detergents are the olefin sulfonates including long chain alkene sulfonates, long chain hydroxyalkane sulfonates or mixtures of alkene sealants and hydroxyalkane sulfonates. The olefin sulfonate detergents may be prepared in a conventional manner by the reaction of SO
with long chain olefins containing from about 8 to 25, and preferably from about 12 to 21 -13~-~giSC~3 carbon atoms, such olefins having the formula ~CII=CIIRl wherein it a higher alkyd group of from about 6 to` 23 carbons and R] is on nl~yl group containing from about l to 17 carbon atoms, or hydrogen to form a mixture of sultans and alkene sulfonic acids which is then treated to convert the sultans to sulfonates. Other examples of sulfate or sulfonatc detergents are paraffin sulfonates containing from about 10 to 20 carbon atoms, and _ preferably from about 15 to 20 carbon atoms. The primary paraffin sulfa-notes are made by reacting long chain alpha olefins and bisulfites. Pane-fin sulfonates having the sulfonate group distributed along the paraffin chain are shown in USE ooze. 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 RO(C2H40)mS03M, wherein R is a fatty alkyd of from lo to 18 carbon atoms, m is from 2 to 6 (preferably having a value from about l/5 to 1/2 the number of carbon atoms in R) and M is a solubilizing salt-forming cation, such as an alkali metal, am~onium, lower alkylamino or lower alkanolamino, or a higher alkyd Bunsen sulfonate wherein the hither alkyd is of lo to 15 carbon atoms. The proportion of ethylene oxide in the polyethoxyla~ed higher alkanol sulfate is preferably 2 to S moles of ethyl tone oxide groups per mole of anionic detergent, with three moles being most preferred, especially when the higher alkanol is of if to lo carbon atoms.
To maintain the desired hydrophile-lipophile balance, when the carbon atom content of the alkyd chain is in the lower portion of the 10 to 18 carbon atom range, the ethylene oxide content of the deterrent may be reduced to about two moles per mole whereas when the higher alkanol is of 16 to 18 oar bun atoms in the hither part of the range, the number of ethylene owe groups my be increased to 4 or S and in some caves to as high as o. 9. Similarly, the salt-orming cation may be altered to obtain the best sublet. It may be any suitably svlubili~in~ metal or radical but will most ~rcqucnLly be -lo-alkali metal, e.g., sodium, or ammonium. If lower alkylamine or alkanol-amine groups are utilized the alkyds and alkanols will usually contain from l to 4 carbon atoms and the amine and alkanolamines may be mQno-) dip and tri-substituted, as in monoethanolamine, diisopropanolamine and trimethylamille. A preferred polyethoxylated alcohol sulfate detergent is available from Shell Chemical Company and is marketed as Nudely 25-3S.
The most highly preferred water-soluble anionic detergent come pounds are the ammonium and substituted ammonium (such as moo, do and in-e~hanolamine), alkali metal (such as, sodium and potassium) and alkaline lo earth metal such as, calcium and magnesium) salts of the higher alkyd bent gene sulfonates, olefin sulfonates and higher alkyd sulfates. long the ; above-listed avionics> the most preferred are the sodium linear alkyd Bunsen sulfonates (LABS), and especially those wherein the alkyd group is straight chain alkyd radical of 12 or 13 carbon atoms.
I've non ionic synthetic organic detergents are characterized 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 alkyd Dramatic hydrophobic compound with ethylene oxide (hydrophilic in nature). Practically any hydrophobic compound having a car boxy, hydroxy, amino or amino group with a free hydrogen attached to the nitrogen can be condensed with ethylene oxide or with the polyhydration product thereof, polyethylene glycol, to forJn a non ionic detergent. The length of the hydra-Philip or polyoxyethylene chain can be readily adjusted to achieve the desired balance between the hydrophobic and hydrophilic groups.
The non ionic detergent employed is preferably a poly-lower Alec-fated higher alkanol wherein the alkanol is of 10 to 18 carbon atoms and whereirl the number of moles of lower alkaline oxide of 2 or 3 carbon atoms) is from 3 to I 0 such materials it is preferred to employ those wherein the higher alkanol is a higher fatty alcohol ox 11 to 15 carbon *Trade mark _ 15 -atoms and which contain Tom 5 to 9 lower alkoxy groups per mole.
Preferably, the lower alkoxy is ethics 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., Nudely 25-7 and Nudely 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 wherein 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 Turtle 15-S~9 J 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 higher molecular weight nonionics, such as Nudely 45-11, which are similar ethylene oxide condensation products of higher fatty alcohols, the higher fatty alcohol being of 14 to lo carbon atoms and the number of ethylene oxide groups per mole being about 11. Such products are also made by Shell Chemical Company.
Zwitterlonic detergents such as the button, and sulfobetaines having the following formula are also useful:

!

So ~301-126$

R2\
R / N - I - X -O

wherein R is an alkyd group containing from about 8 to 18 carbon atoms, R2 and R3 are each an alkyd or hydroxyalkyl group containing about 1 to 4 carbon atoms, R4 is an alkaline or hdyroxyalkylene group containing 1 to 4 carbon atoms, and X is C or SO. The alkyd group can contain one or more intermediate linkages such as amino, ether, or polyether linkages or non-junctional substituPnts such as hydroxyl or halogen which do not substantially affect the hydrophobic character of the group.
When X is C, the detergent is called a button; and when X is SO, the detergent is called a sulfobetaine or sultan.
Cat ionic surface active agents may also be employed.
They comprise surface active detergent compounds which contain an organic hydrophobic group which forms pat of a cation when the compound is dissolved in water, and an anionic wrap Typical eationie ~urfaee active agents are amine and qua~ernary ammonium compounds.
Examples of suitable synthetic cohesion deterrents include: normal primary amine of the formula RNH~ wherein R
is an alkyd group ~ontaininy from about 12 to 15 atoms; dominoes having the formula RNHC~H4NH~ wherein R it an alkyd group COntainincJ from about 12 to 22 carbon atoms, such as M-2-amino-ethyl stroll amine and N-2-aminoethyl. myristyl amine; aside-linked amine ugh as those havincl the formula ~lCONHC2H4MH2 Warren Al is an allele group eontainin~ about 8 to 20 carbon atoms, such as Pneumonic ethyls~e3ryl amine and N-amlno ethyl-myristyl amine; qua ternary Amman compounds warily ~ypieally on ox the croup linked to the nitrogen atom is an ~llkyl group -lo-containing about 8 to 22 carbon atoms and three of the groups linked to the nitrogen atom are alkyd groups which contain l to 3 carbon atoms, including alkyd groups bearing inert subset-tents, such as phenol groups, and there is present an anion such as halogen, acetate, methosulfate, etc. The alkyd group may contain intermediate linkages such as aside which do not substantially affect the hydrophobic character of the group, for example, stroll amino propel qua ternary ammonium chloride.
Typical qua ternary ammonium detergents are ethyl-dimethyl-stearyl-ammonium chloride, benzyl-dimethyl-stearyl ammonium chloride, trimethyl-stearyl ammonium chloride, trimethyl-cetyl ammonium bromide, dimethyl-ethyl-lauryl ammonium chorine, dimeth~l-propyl-myristyl ammonium chloride, and the corresponding methosulfates and acetates.
Ampholytic detergents are also suitable for the invent lion. Ampholytic detergents are well known in the art and many operable detergents of this class are disclosed by Schwartz, Perry and Bench in the aforementioned "Surface Active Agents and Detergents." Examples of suitable amphoteric detergents include: alkyd betaiminodipropionates, RN(C2H~COOM~2; a1kyl heta-amino preappoints, RN(H)C2H4COOM; and long chain imidazole derivatives having the general formula:

I
N OH
if 1 2 R-C _ N ~CH2CH~CH2CQM

wherein in each of the above formulae is an cyclic hydra-phobic group containing from about 8 to 18 carbon atoms and M
is a cation to neutralize the charge of the anion. Specific or operable amphoteric detergents include the disodium salt of undecylcycloimidinium-ethoxyethionic acid~2-ethionic acid, dodecyl beta ala nine and the inner salt of 2-trimethylamino Laurie acid.
The bleaching detergent compositions of the invention optionally contain a detergent builder of the type commonly used in detergent formulations. Useful builders include any of the conventional inorganic water-soluble builder salts, such as, for example, water-soluble salts of phosphates, pyrophosphates, orthophosphates, polyphosphates, carbonates, and the like.
Organic builders include water-soluble phosphonates, polyphos-founts, polyhydroxysulfonates, polyacetates, carboxylates, polycarboxylates, succinates and the like.
Specific examples of inorganic phosphate builders include sodium and potassium tripolyphosphates, pyrophosphates and hexametaphosphates. The organic polyphosphonates specific gaily include, for example, the sodium and potassium salts of ethanes l-hydroxy-l,l-diphosphonic acid and the sodium and potassium salts of ethane~-1,1,2-triphosphonic acid. Examples of these and other phosphorous builder compounds are disclosed in US. Patent Nos. 3,213,030; 3,422,021, 3,422,137 and 3 7 400,176. Pentasodium tripolyphosphate and tetrasodium pyrophosphate are especially preferred water-soluble inorganic builders .
Specific examples of non-phosphorous inorganic builders include water-soluble inorganic carbonate and I carbonate salts. The alkali metal, for example, sodium and potassium, carbonates and bicarbonates are particularly useful herein.
Water-soluble organic builders are also useful or example, the alkali metal, ammonlum and substituted ammonium polyacetates, carboxylates, polycarboxylates and polyhyd,roxy-~22~;1D3 oilily sulfonates are useful builders for the compositions and processes of the invention. Specific examples of polyacetate and polycar-boxy late builders include sodium, potassi~n, lithium, ammonium and substituted ammonium salts of ethylene diaminetetracetic acid, nitrilotriacetic acid, Bunsen polycarboxylic it pent-and twitter) acids, carboxymethoxysuccinic acid and citric acid.
Water-insoluble builders may also be used, portico-laxly, the complex silicates and more particularly, the complex sodium alumina silicates such as, zealots, e.g., zealot PA, a type of zealot molecule wherein the univalent cation is sodium and the pore size is about 4 Angstroms. The preparation of such type zealot is described in US. Patent 3,114,603. The zealots may be amorphous or crystalline and have water of hydration as known in the art.
An inert, water-soluble filler salt is desirably in-eluded in the laundering compositions of the invention. A
preferred filler salt is an alkali metal sulfate, such as, potassium or sodium sulfate, the latter being especially preferred.
Various adjutants may be included in the laundry deterrent compositions of the invention. In general, these include perfumes; colorants, e.g., pigments and dyes; bleaches, such as, sodium perorate, anti redeposition agents, such as, alkali metal salts of carboxymethylcellulose; optical brighten-ens, such as, anionic, cat ionic or non ionic brighteners; foam stabilizers, such as alkanolamides, and the like, all of which are well-known in thy fabric washing art for use in detergent compositions. Flow promoting agents, commonly referred to as flow aids, may ask be employed to maintain the particulate I compositions as free-flowing beads or powder. Starch derive-tire and special clays are commercially available as additives which enhance the flyability of otherwise tacky or pasty particulate compositions, two of such clay additives being presently marketed under the trade names "Sat intone" and "Microsil".
A preferred bleaching detergent composition in accordance with the invention typically comprises (a from about

2 to 50%, by weight, of a bleaching agent comprising a per oxygen compound in combination with an activator therefore by from about 5 to 50~, by weight, of a detergent surface active agent;
(c) from about 1 to about Z0~, by weight, of a detergent builder salt; and (d) from about 0.1 to about 10%, by weight, of a sequestering agent; such composition being characterized by being substantial free of (i) water-soluble silicate compounds and (ii) agglomerate particles which essentially comprise said activator, a water-insoluble silicate compound and a non ionic surfactant. The balance of the composition will predominantly comprise water filler salts, such as, sodium sulfate, and minor additives selected from among the various adjutants described above.
: The particulate bleaching detergent compositions of the invention are prepared by admixing the bleaching agent and optional sequestering agent Vito the -aye-I,.

:3L2~ 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 water-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 I by weight, such as may occur with the use of silicate-containing pigments or dyes, or upon contact of the aqueous kosher slurry with residual amounts of sodium silicate in the spray tow}, is contemplated by the present invention.
The spray drying of a silicate-free detergent formulation slay 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 Metro-awls comparable thereto. The strength of the spray dried beads may also he en-hanged by maximizing the solids content of the silicate-free slurry in the crutches 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-seeders well known in the art. Suitable coating materials include compounds such as magnesium sulfate, polyvinyl alcohol, Laurie 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 co about Lou parts of active oxygen per million parts of solution, a concentration of from about 5 to about 40 Pam being generally preferred.
The particulate bleaching detergent Compositions described above may be produced by such methods as spray-dryirlg, dry-blendin~, or agglomeration of the individual components.

~22~ 3 A preferred silicate-free bleaching detergent composition is comprised of the foliating:

: _ Component .
Sodium linear C10 - C13 6 alkyd Bunsen sulfonate Ethoxylated Oil - C18 primary alcohol (11 moles HO per mole alcohol) Soap (sodium salt of C12 - C22 4 carboxylic acid) Pentasodium tripolyphosphate (TOP) 32.0 ETA 0~5 TOED 2.3 Carboxymethyl cellulose 0.5 Sodium perorate tetrahydrate 13.2 Optical brighteners, pigment and 0.4 perfume Proteolytic enzymes 0.5 Sodium sulfate and water. balance ;5~3 The foregoing product is produced by spray drying an aqueous slurry con-twining 60%, by weight, of a mixture containing all of the above components except the enzyme, perfume, TOED and sodium perorate. The resultant particulate spray dried product has a particle size in the range of 14 mesh to 270 mesh, (US. Sieve Series). The spray dried product is then mixed in a rotary drum with the appropriate amounts of sodium perorate of similar mesh size, TOED, enzyme and perfume to yield a particulate product having a moisture of approx-irately 18%, by weight.
The above-described product is used to wash soiled fabrics by hand-washing as well as in an automatic washing machine, good launderillg and bleaching per-pheromones 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 erupt Percent Alkyd Bunyan sulfonate 4-12 Etho~ylated alcohol 1-6 Soap 1-10 Enzymes 0.1-1 ETA 0~1-2 Sodium perorate 5-20 For highly concentrated heavy duty detrain powder, the alkyd Bunsen sulfa-nave, TOP and the ape components in the above described Composition may be de feted, and the ethoxylated alcohol content may be increased to an upper limit of 20%.

Bleaching tests are carried out as described below comparing the bleaching performance of water-soluble silicate-free bleaching detergent compositions in accordance with the invention and corresponding silicate-cont~ining combo-sessions, the latter compositions being comparable to the former in nearly all respects except for the presence of a water-soluble silicate compound. Specie focally, the silicate free compositions are characterized by the presence of sodium metaborate; the silicate-containing compositions contain sodium silicate.
The compositions are formulated by post-adding to a spray dried particulate deter-gent composition, granules of sodium perorate tetrahydrate and tetraacetyl ethylene Damon (TOED) to form the bleaching detergent compositions shown in liable 1 below. The numbers indicated in the Table represent the percentage of each component, by weight, in the composition.

-24~

26~;~3 Table 1 Component Composition A B C D E F
Sodium linear C10 - C13 alkyd 8% 8% 8% 8% 3% 8%
Bunsen sulfonate _ Ethoxylated Oil - C18 primary 3 3 3 3 3 3 alcohol (11 moles HO per mole alcohol) Soap (sodium salt of C12 - C22 3 3 3 3 3 3 carboxy]ic acid) Sodium silicate (lNa20:2SiO2) - - - 4 4 4 Sodium metaborate 5 5 5 - - -Pentasodium tripolyphosphate 35 35 35 35 35 35 : (TOP) Optical brlghte~er (stilbene3 0.2 0.2 0.20.2 0.2 0.2 Sodium perorate tetrahydrate 6 6 6 6 6 6 ETA

EDlTEMpA I ) 1 _ _ 1 Sodium sulfate ` 21 20 20 21 20 20 ::
Water ----Balinese _ _ tl)Sold as Request 2041 by Monsanto Company, So. Louis, Missouri . ~;2;2~5~3 TEST PROCEDURE

Bleaching tests are carried out in an Ahab apparatus at maximum temper-azures of 60C and 90C, respectively, as hereinafter described. 600 ml of tap water having a water hardness of about 320 Pam, as calcium carbonate, are introduced into each of six buckets of the Ahab. Six cotton swatches (8 cm x 12 cm) soiled with immedial black are introduced into each bucket, the initial reflectance of each swatch being measured with a Gardner AL 20 reflectometer~
Six grams of each of compositions A through F described in Table l are introduced separately into the six buckets of the Ahab, a different compost-lion being introduced into each bucket. The bleaching detergent compositions are thoroughly mixed in each bucket with a blender-type apparatus and the wash cycle thereafter initiated. The bath temperature, initially at 30C, is alloyed to rise about 1 Centigrade per minute until the maximum test temperature (60 or 90CC~ is reached, such maximum temperature being then maintained for about 15 minutes. The buckets are then removed and each swatch washed twice with cold water and dried.
The final reflectance of the swatches are measured and the difference Rod between the final and initial reflectance values is determined. An average value of Rod for the six swatches in each bucket is then calculated. The results of the bleaching tests are set forth below in Table 2, the values ox Rod being pro-voided as an average value fur the particular composition and test indicated.

I

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~L2~5~3 As indicated in Table I the silicate-free compositions (A, B and C) provide an improved bleaching performance relative to the silicate-containing compositions at both test temperatures. Among the silicate containing combo-sessions, the one which contains 1% EDITE~PA (F) provides an improved bleaching effect relative to composition D which contains no sequestrant, but only at the higher test temperature of 90~C. However, at both test temperatures, the silicate free composition A containing no sequestrant provides the best bleach-in effect of all compositions tested.

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~22Ç~3 The active oxygen concentration in solution is determined 85 a function of time for wash solutions containing each of compositions A through F described in Table l. the test procedure is as follows:
One liter of tap water 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 are added Jo the beaker (tome = O) with thorough mixing Jo form a uniform wash solution. After given periods of time (5, 15, 30, 45 and 60 minutes), a 50 ml Alcott is withdrawn from the wash solution and the total active oxygen concentration is determined by the pro-seedier set forth below.
Determination of Total Active O Concentration The aforementioned 50 ml Alcott is poured into a 300 ml erlenmeyer flask fitted with a ground stopper and containing 15 ml of a sulfuric/molybdate mix-lure, the latter mixture having been prepared in large-scale amounts by disk solving ~.18 grams of ammonium molybdate in SO ml of deionized water and then adding thereto 32U Al of H2S04 (about 36N~ with stirring. The solution in the erlenmeyer is thoroughly mixed and 5 ml of a 10% KIT 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 seven minutes. The solution in the flask is then titrated with a solution of Urn sodium trio-slot in deionized water. The volume of thiosulface required in ml, is equal to the total await oxygen concentration, in millimole~liter, in the wash solution. The tests results for the Sty compositions tested are shown in Table 3 below.

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Jo _, _ .
E

C En Jo _ a us I ~_~ o O
'I _ o I Jo Jo Jo ox C'J
,_ , on O O O
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: . __ I_ I? Cal Jo o C C I

S : 1 . ___~_ I__ _ I Pi Lo I O CUD
us _ n Jo I I :

VC Jo I_ I_ I: 30~`- so O, ox ,__.~

6S~3 .

As shown in Table 3, the silicate-free compositions A, B and C are substantially more stable and are characterized by a far slower loss of active oxygen from solution than the corresponding silicate-containing come positions D, E and F, respectively. Among the silicate-containing compost-lions, the one containing 1% EDITEMPA (F) provides the maximum stability, however, such composition is less stable than all of the silicate-free come positions, including composition A which contains no sequestrant. Among the silicate-free compositions, the presence of a sequestrant in compositions B
and C results in improved oxygen stability relative to composition A.

Bleaching tests are carried out in an Ahab apparatus as indicated below comparing the bleaching performance of bleaching detergent composition free of water-soluble silicates in accordance wit the invention (A) and a water-soluble silicate-containing composition (By. As indicated below, the two compositions are comparable in nearly all respects except for the presence of sodium silicate in composition A. A crystalline zealot material is present in both compositions.
The compositions are formulated by post-adding to a particulate detergent come position formed from an aqueous slurry which is dried on a steam drum dryer (an operation equivalent to spray drying particles of sodium perorate tetrahydrate and tetraacetyl ethylene Damon TODD) to form the bieachin~ detergent combo-session shown in Table 4 below. The numbers indicated in the Table represent the percentage of each component, by right it the composition.

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.

Table 4 Component Composition A B
(silicate-containin~) (silicate-free) Sodium linear ClO-Cl3 alkyd 6 6 Bunsen sulfonate _Ethoxylated Cll-Cl8 primary 3 3 alcohol (11 moles HO per mole alcohol) Soap (sodium salt of G12-C22 4 4 carboxylic acid) Sodium silicate (lNa20:2SiO2) 4 ---Pentasodium tripolyphosphate lo 19 (TOP) Optical brightener (stilbene) 0.2 0.2 Zealot lo lo Sodium perorate tetrahydrate 13.3 13.3 TOED 2.3 2.3 Water S 5 Sodium sulfate balance balance The bleaching test is carried out in accordance with the text procedure set forth in Example 2, and the results of such test are shown in Table S below.The values of Rod are provided as an averse value for the test indicated.

ox Table 5 . Rod (average) Composition containing Composition free of Test water-sol~ble water-soluble - To locate _ _ silicate _ 60C 5.0 6.1 ,' _ .
Jo 95G 13.2 14.9 :

: As indicated in Table 5, the water-sol~ble silicate-free composition B
: provides a significantly improved bleaching performance relative to silicate-containing composition A.

: :

Claims (30)

1. WHAT IS CLAIMED IS:
   l. A particulate bleaching detergent composition comprising:
   (a) a bleaching agent comprising a peroxygen compound in combination with an activator therefor; and (b) at least one surface active agent selected from the group consist-ing of anionic, cationic, nonionic, ampholytic and zwitterionic detergents; said bleaching detergent composition being substantially free of (i) water-soluble silicate compounds and (ii) agglomerate particles which essentially comprise a mixture of said activator, a water-insoluble silicate compound and a nonionic surfactant.
2. 2. A composition in accordance with claim l also containing a sequestering agent.
3. 3. A composition in accordance with claim 2 wherein said sequestering agent comprises ethylene diamine tetraacetic acid and/or a water-soluble salt thereof.
4. 4. A composition in accordance with claim 2 wherein said sequestering agent com-prises diethylene triamine pentamethylene phosphonic acid and/or a water-soluble salt thereof.
5. 5. A composition in accordance with claim 1 which is substantially free of se-questering agents having a stability constant above about 20 for Cu2+ complex formation in water at 25°C and at an ionic strength of 0.1 mole/liter.
6. 6. A composition in accordance with claim l wherein said bleaching agent com-prises an alkali metal perborate in combination with tetraacetyl ethylene diamine (TAED).
7. 7. A composition in accordance with claim 6 wherein said TAED is contained in granules in combination with a mixture of sodium and potassium triphosphate.
8. 8. A composition in accordance with claim 6 wherein said TAED has the follow-ing particle size distribution: 0-20% greater than 150 micrometers (µm);
   10-100% greater than lOOµm but less than 150µm; 0-50% less than 75µm;
   and 0-20% less than 50µm.
9. 9. A composition in accordance with claim 6 wherein about 50% of the particles of TAED have a size greater than 160µm.
10. 10. A composition in accordance with claim 1 wherein at least 80%, by weight, of said agglomerate particles are comprised of said mixture.
11. 11. A composition in accordance with claim 1 also containing a detergent builder salt.
12. 12. A composition in accordance with claim 1 wherein said builder salt is a zeolite
13. 13. A composition in accordance with claim 1 wherein said surface active agent is an anionic detergent.
14. 14. A composition in accordance with claim 13 wherein said anionic detergent is a linear alkyl benzene sulfonate.
15. 15. A composition in accordance with claim l also containing a bentonite clay.
16. 16. A bleaching detergent composition comprising:
    (a) from about 1 to about 50% by weight, of a bleaching agent comprising a peroxygen compound in combination with an activator therefor;
    (b) from about 5 to about 50%, by weight, of a detergent surface active agent selected from the group consisting of anionic, cationic, non-ionic, ampholytic and zwitterionic detergents;
    (c) from about l to about 60%, by weight, of a detergent builder salt;
    (d) from about 0.1 to about 10% by weight, 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 and (ii) agglomerate particles which essentially comprise a mixture of said activator, a water-insoluble silicate compound and a nonionic surfactant.
17. 17. A composition in accordance with claim 16 wherein said bleaching agent com-prises an alkali metal perborate in combination with a tetraacetyl ethylene diamine.
18. 18. A composition in accordance with claim 16 wherein at least 80% by weight, of said agglomerate particles are comprised of said mixture.
19. 19. A composition in accordance with claim 16 wherein said sequestering agent comprises ethylene diamine tetraacetic acid and/or a water-soluble salt thereof.
20. A composition in accordance with claim 16 which is substantially free of sequestering agents having a stability constant above about 20 for Cu2+
    complex formation in water at 25°C and at an ionic strength of 0.1 mole/liter.
21. 21. A process for bleaching which comprises contacting the stained and/or soiled material to be bleached with an aqueous solution of a particulate bleaching detergent composition comprising:
    (a) a bleaching agent comprising a peroxygen compound in combination with an activator therefor; and (b) at least one surface active agent selected from the group consisting of anionic, nonionic, cationic, ampholytic and zwitterionic deter-gents, said bleaching detergent composition being substantially free of (i) water-soluble silicate compounds and (ii) agglomerate parti-cles which essentially comprise a mixture of said activator, a water-insoluble silicate compound and a nonionic surfactant.
22. 22. The process of claim 21 wherein the bleaching agent comprises an alkali metal perborate in combination with tetraacetyl ethylene diamine.
23. 23. The process of claim 21 wherein the bleaching agent also contains a peroxy-acid compound.
24. 24. The process of claim 22 wherein said TAED has the following particle size distribution: 0-20% greater than 150 micrometers (µm); 10-100% greater than 100µm but less than 150µm; 0-50% less than 75µm; and 0-20% less than 50µm.
25. 25. The process of claim 21 wherein said composition also contains a sequester-ing agent.
26. 26. The process of claim 25 wherein said sequestering agent comprises ethylene diamine tetraacetic acid and/or a water-soluble salt thereof.
27. 27. The process of claim 21 wherein said composition also contains a deter-gent builder salt.
28. 28. The process of claim 27 wherein said builder salt comprises pentasodium tripolyphosphate.
29. 29. The process of claim 27 wherein said builder salt is a zeolite.
30. 30. The process of claim 21 wherein said bleaching detergent composition also contains a bentonite clay.