Note: Descriptions are shown in the official language in which they were submitted.
37g8 2 1 ~ PCI`~U~92/~
PERO~AC~ID Bl,~E~lR~QR ~C)MP~$I~IONS
This invention relates to solid peroxy acid bleach precursor
compo~itio~ a~d especially to particulat~ deterge~t compositio~s
incorpora~ing inorgal~ic perhydr~te bleaches together with N- or C)-
acyl group - containi~g per~ycarboxylic acid bleach precursors ~so- ~:
called bleach activators~. Such com~sitio~s have come iIltO ;~
widespread use in recent years as heavy du~y fabric cleaning ~;
products~ particularly in a~tomatic washing machines. ~he growth
i~ usage of bleach activators has mirrored a decrease in fabric wash
temperatures which itself has acc~mpanied an increase ill the ;
proportion of ~abrics that are coloured.
. .
One problem ~hat has become more sig~ Scant as a result of these
tretlds is that of damage to fabric colours and materials caused by the
development of localised high concentrations of bleaching species.
High bleach concentrations can arise around any particulate
bleaching species for several reasons. The bleaching species may
itself have . n intrinsically low solubility9 its solubili~ ~ay have been ; -
hindered by ~he presence of other materials su~h as viscous :
surfactant phases or the agitation regime i~ the immediate ~;
environme~t of the bleach species may not be high eIlough ~o
disperse the dissolved bleach. Where a bleach activator forms a
compollent of the composition the potential problem is increased. Ln ;
addition to thc potential ~or localised high concentra~ioIls of ::
perhydroxyl ion arising from dissolution of the inorganic perhydxate
normally co~tained in laundry detergent compositions, the
perhydrolysis of the ble~ch activator to form peroxycarboxyl anions
2101~
WO g2/137~8 PCI'/US92/0~664
can give rise to significant localised pero~ycarboxylate bleach
conceIltrations.
-:
The de~elopment of so-called coIlcentrated products and their
delivery via dispensing devices placed in the machine drum together
with the fabric load has merely se~ed to exacerbate these problems.
Accordi~gly a need exists to provide detergent compositions in which
the bleach activator is incorporated i~ a fo~ that minimises and
pre~erably eliminates damage to fabric colours aIld materials during :~
its dissolution alnd perhydrolysis iEl the wash liquor.
The prior ar~: coIlta~s ~mer~us e~amples of bleach activators coated
or agglomeEated so as to increase their stability on storage in
detergent comp~sitio~s and/or to influence their solution behaviour.
EP-A-0070474 discloses grar~u!ate bleach activators prepared by
spray drying an aqueous pumpable dispersion containiIlg an N-acyl
or O-acyl compound together with at least one water soluble
cellulose ether, starch or starch derivath~e in a weight ratio of
activator to coa~ing of from 98:2 to 90:10.
GB~A-1507312 discloses the c~ating of bleach activators with a
mi~ture of alkali metal C~ - C22 fatty acid salts i~ admixture with
the correspo~ding ~atty acids. GB-A~1381121 employs a molten
coating of j~ç~ C14 - Clg ~atty acid xnixtures to protect solid
bleach acti~ators. GB-A-1441416 discloses a similar process
ernployi~g a mixture of C12 - C14 fatty acids and Clo - C20
aliphatic alcohols. EP-A-0375241 describes stabilised bleach
activator extrudates in which Cs- C1g alkyl peroxy carboxylic acid
precursors are mixed with a binder selected from anionic and
nonionic surfactants, film forming polymers fatty acids or mixtures
of such binders.
EP-A-0356700 discloses compositions comprisirlg a bleach activator,
a water soluble film forming polymer and 2-15~o of a C3-C6
polyvalent carboxylic acid or hydroxycarboxylic acid for enhanced
stability and ease of dispersion/solubility. The carboxylic acid, of
Yo 9~13798 2 1 0 1 ~ ~ ~ P~l`/U~i~2/~
which a preferred e~cample is eitric acid, is dry mixed with the
bleach activator and theIl granulated with the film forming polymer.
The citric acid is asserted to provide ~ enhanced rate of dissolution
of the bleach acti-lator granules.
EP-A~382464 conce~s a process for eoating or e~capsulation of
solid partieles includi~g bleaching compounds and bleach acti~rators
in which a mel~ is ~ormed of coating material in which the partieles
form a disperse phase, the melt is destabilised and then caused to
crumble to a particulate material in which the disperse phase
particles are embedded i~ the COIl~UOUS (coati~g~ phase. A variety
of coat~g materials are disclosed a~d certain materials such as
polyacrylic acid and cellulose ace~te phthala~ are taught as be~g
useful where release of the coated material is dependeIlt on pH.
The s~erall emphasis in the prior art has ~us been orl the protection
of the bleach ac~avator against a hostile enviro~ent dur~rlg storage
and relatively little attention has bee~ paid to the dissolu~ion ;~
characteristics of the coated or agglomerated material in use. Where ~;;
coating and/or agglomeratlorl has been prsposed with poorly soluble
materials such as fatty acids9 this has resulted in a rate of
perhydrolysis of the bleach acti~ator which is slower than that which
would occur if it had not been so protected. A~y use of more rapidly
soluble materials such as citric acid has bee~ in the context of an
a~glomerate component in which more rapid solution of the bleach
activa~or has been the objective. In both instances, because
perhydrolysis comme3~ces as soon as the d~tergent product starts to
dissolYe and ~rm an alk~line hydrogen peroxide solutio~ the
problem of localised peroxy acid bleach concentrations has remained
unsolved.
One solutiorl to this problem would be to delay the start of
perhydrolysis in order to aYoid the ~abric colour damage problems
associated with the dissolution behaviour of other detergent product
components. However it is important thas perhydrolysis of the
bleach precursor and subsequent dispersion of the peroxycarboxylate
wo 92/13798 2 1 ~ 8 PCI/US92/00664
bleach is as rapid as possible whè~ it commences bec~llse of the
short wash times of modern automatic washing machines.
The problem that arises in simultaneously satisfying these two
objectives does not appear to have been recognised in the prior art.
It is l~ow~ that the rate of perhydrolysis of a percar~o~cylic acid
bleach precursor in an aqueous o~cidising medium is progressively
reduced as ~he pH of the medium is reduced, particularly whe~ the
p~I falls below the pKa of the pare~t acid of the precursor leaviIlg
group. However the fatty acids taught as coating agents in the prior
art are llot usefill as a mea~s of providi~g a low pH e~Yiro~ment in
aqueous wash liguor because of their i~solubility. Moreover fatty
acids used as coating a~/or agglomer~ing agen~ ~or pero~y acid
bleach precursors have been found to reduce the rate of
perhydrolysis of the lat~er, therelby redl;lcing the e~fectiYene~s of the
resultant peroxycarbo~cylic acid bleach.
The Applicant has ~ow surprisingly ~ound that acidic materials
having certain specified characteristics can be used to providç a
sur~ace treatment to particulate pero~y acid bleach precursors, tha~
delays the orlset of perhydrolysis dllring dissolution of the product
under ~he corlstrained agi~ation conditio~s ~f a loaded washing
ma~hine drum without adversely hinderiIlg perhydrolysis when it
occurs.
According to the present invention there is provided a solid
peroxyacid bleach preeursor composition comprising a particulate
peroxyacid bleach precursor material, said precursor containing one
or more N- or O aeyl groups and having a Mpt> 30C, the
external surfaces of said particulate peroxy acid bleach precursor
material being treated with an organic acid compound so as to adhere
said compound to said external sur~aces, said compound being
preserlt i~ an amount of from 2% to 20~o by weight of the treated
particulate, said organic acid compound having an aqueous solubility
of at least Sg/lOO~g of water at 20C and a Mpt ~ 30C, wherein
said ~reated particulate bleach precursor ma~erial produces, a~er 3
21~1~48
VO 92/1379B PCI/US92~00$64
minutes in a E~eaker Perhydrolysis Test at 20C, at least 90~ of the
pero~y acid that is produced under the same eonditio~s by said
particulate bleach precursor material in untreated ~orm.
Preferably the organic ~id compound is a mo~omeric or oligomeric
carboxylate that has an aqueo~s solllbility of at least 20g/1OOg of
water at 20~C. Most pre~erably the eompound is a mo~omeric
aliphatic car~oxylic acid of very hîgh solubility and Mpt~40 C.
I~ is important for the purposes of the present inven~io~ tha~ the
e~ternal surfaces of the peroxy bleach precursor particulate, whether
in the ~orm of individual particles or agglomer~es~ are t~eated so
hat the organic acid co~npound is adhered thereto. The trea~nent
can be such as to provide the u~mpound in the form of a co~ti~uous
or disconti~uous coating or as masses of the acid comp~und
dispersed o~ the particulate surace or as i~dividual particle~ :~
dispo~ed at random on the sur~ace. The requireme~t i that the
surface treatment material be immediately available, OIl e~posure to
an aque~us medium, to dlssolve ra~idly a~d proYide a~ a~id pH
en~ironment arourld the exteric~r of the bleach precursor particulate.
~or this reason, irlcorporation of the organic acid compound as an
- agglomerati~g agent dispersed with~ ehe pero~yacid bleach
precursor pa~iele does not provide the benefit of the inventioIl. This
is beeause, u~der ~he conditions of dissolution of a concentrated
graIlular laundry product, particularly when delivered to washing
machi~e drum by a dispellsing device, an agglomerated but non
sur~ace ~reated pero~cyacid bleach precursor perhydrolyses to a
significant e~tent and generates high bleach concentrations that give
rise tQ localised ~abrie damage.
The solid peroxyacid bleach precursor eompositions of the presen~
invention inco:rporate precursors contai~ing one or more N- or 0-
acyl groups, which precursors can be selected from a wide xange of
classes. Suitable classes include anhydrides, esters, imides and
acylated derivatives of imidazoles and o~cimes, ~d e~amples of
useful materials wi~ these classes are diselosed in GB-A-1586789.
The most preferred classes are esters such as are disclosed in
wo 92/137~ 2 1 ~ 8 6 PCI'/VS92/00~64
GB-A-836988, 864,798, 1147871 an~ 2143231 and imides such as are
disclosed iIl GB-A-855735 & 1246338.
Specific O-acylated precursor compounds irlelude 2,3,3-tri-methyl
hexanoyl oxyben~ene sulfonates, be~y~ oxybe~e~e sulfonates and penta
ace~yl glucose.
Particularly p~erred preeursor compounds are the N-,N,NlN1 tetra
acetylated compound of formula
O O
Ii 11
3 \ / C C~I3
N - (c~I2~x ~ ~ \
C~3 C~ C -CH3
Il 11 .~
O
wherein x call be O or ~ integer between 1 & 6.
Exa~ples i~clude ~etra ace~l methylene diamine (TAMD) in which x= 1,
te~a acetyl ethylelle diamine ~D) in which x=2 and tetraacetyl
hexyle~e dia~e CTAHD) iD which x=6 These and analogous
compounds are described in GB-A-907356. The most pre~erred
peroxyacid bleach precursor is TAED.
Solid peroxyacid bleach precursors useful in the present inven~ion have a
Mpt ~ 30C a~d pre~erably ~ C~ Such precursors will normally be in
fine powder or clryst~lline form in which at least 90~ by weight of the
powder has a particle size ~150 micrometers.
This powder ean !be surface treated directly but is more usually
agglomerated, prior to surface treatmen~, to form particulate rnaterial, at
least 85 ~o of which has a par~icle size between 4()0 and 1700
mierometers. Suitable agglomerating agents include C12-(: 18 fatty
acids, C12-C1g aliphatic alcohols condensed with from 10 to 80 moles of
ethylene o~cide ~er mole of alcohol, cellulose derivatives such as me~hyl,
carboxymethyl and hydroxyethyl cellulose, polyethylene glycols of MWt
4,000 - 10,000 and polymeric materials such as polyvinyl pyrrolidone.
vo~12/l3798 2i~ 8 PClr/US92/0~664
Agglomerat~ particulate precursor material does not itself provide
the benefi~ of the invention but is a pre~erred form of the precursor
to which the organic acid compound is applied as a sur~ace
treatment.
The organic acid compound ~ust satisfy several criteria. Firstly it
must be a solid at ambient tem~eratures and so must ha~e a Melti~g
Point of at least 30C and preferably of at least 40C. Preferred
organic acid compounds will have a Melti~g Point in e~cess of 50C.
Secondly the organic acid compou~d ~ust be ~ghly soluble i~ water
at ambie~t temperaeures, highly soluble be~g defined for ~e
purpvses of the prese~t iIl~rention as at lea~t Sg of the acid dissolvi
in lOO~g of distilled water a~ 20C. Pre~erably the org~c acid
compou~d has a solubili~ o~ at least 2~/lOOg OI water at 20C and
most pre~rably the organic acid compou~d will dissolve in its own
weight of water at 20C.
Thirdly the orgaI~ic acid compound should have no more than a
mi~or e~fect9 and pre~erably substanti~lly no effec~ on the rate of
perhydrolysis oiF ~e peroxyacid bleach precursor under well agitated
unco~strained conditions. Unc~strai~ed, well agitated conditioIls
are defined ~or ehe purposes of the present Lnventio~ as those existing
in the Beaker Perhydrolysis Test described in detail hereina~er. A
treatment material that has 'no more than a minor e~t' on the rate
of perhydrolysis of the precursor is definedg for the purposes of the
present in~entiorl, as that which a~er 3 minutes in ~e Beaker
Perhydrolysis Test at 20C, permits the production of at least 905~
of ~he peroxyacid that is prod~ced under the same conditions by the
untreated bleach precursor material. Prefer~ly the rates of
perhydrolysis of treated and untreated material are substantially
identical.
Organic acid compolmds suitable as trcating agcnts ~r the purposes
of the present invention comp~ise aliphatic or aromatic morlomeric or
oligomeric carboxylates and pre~erably comprise monomeric
alipha~ic carboxylic acids. Examples of such aliphatic aeid
WO 92/13798 2 1 ~ I ~ 4 8 P~/U~ 2/0~
compou~ds are glycolic, glutamic, citraco~G, succinie9 l~lactic and
citric aeids. The acids are applied at levels of ~rom 2% tQ 2U% by
weight of the treated particulate, more preferably ~rom 2% to 15
and mos~ pre~rably from 3% to 10% by weight of the trea~ed
particulate . Glycolie acid at a level of appro~cimately 5 % by weight
of the treated particulate is a partieularly prefe~red sur~ace treating
agent.
The surface trea~me~ of the ble~eh precursor particulate with the
orga~ic acid compound can be carried out in several ways and the
process i~el~ is not critical to ~he present irlvelltion.
The organic acid compound may be sprayed on as a molte~ material
or as a solutiol~ or dispersion in a solvent/carrier liquid which is
subsequently removed by evaporation. The organic acid compound
caII also be applied as a powder coating e.g. by elec~rostatic
tech~iques although this is less pre~erred as the adherence of -;
powdered coating material is more difficult to achieve and can be `;
more e~pensive.
Molten coati~g is a pre~erred tec~ique for orgarlic acid compotlnds
of Mpt ~ 80C such as glycolic and l-lactic acids but is less
corlvenie~t ~r higher Melti~g Point acids (i.e. ~100C) sueh as
citric acid. For organic acid comp~unds of Mpt~80C, spray on as
a solution or dispersion is preferred. C1rga~ic solvents such as ethyl
and isopropyl alcohol can be used to form the solutions or
dispersio~s, although ehis will necessitate a solYerlt recovery stage in
order to makc their use economic. However, t!he use of orga~ic
solvents also gives rise to safety problems such as flammability and
operator safety and thus aqueous solutions or dispersions are
preferred.
Aqueous solutions are particularly advantageous where the organic
acid compound has a high aqueous solubility (e.g. citric acid) and the
solution has a suffleiently low viscosity to enable it to be handled.
Preferably a concentra~ioll of at least 25 % by weight of the organic
acid compound in the solvent i used in order to reduce the
2 1 ~ 8
.~0 92~13798 P~/US92/00664
drying/evaporatioIl load after sur~ace treatment has taken place. The
treatment apparatus ca~ be any of ~hose normally used for this
purpose, such as inclined rotary pans~ rotary drums aIld fluidised
beds.
Solid peroxyacid bleach precursor composidon~ i~ accorda~ce with
the invention can take a variety of physical ~orms~ s the surfaGe
trea~ed peroxyacid bleach pre~ursor particles may themselves be ~ .
incorporated into other solid compositions suGh as tablets, extmdatgs
and agglomerates. The particulates ca~ also be suspended in
no~aqueous liquid eompositions i~ which the org~c acid~sur~ce
treat~g ma~erial is insoluble and inert. However, the preferred
application ~or the solid peroxybleach precursor compositions of the
inve~tioll is as pa~iculate compo~erlts of gra~lllar detergent
eompositions, particularly the so called eoncentrated detergeIlt
co~npositions tha~ are added to a washing machine by mea~s of a ;~
dosing device placed in the machine dI~m with the soiled fabric load.
Collcentrated granular detergent compositions dispensed into the
wash liquo~ via a dosing de~ice are mc)re subject to dissolutiotl -
problems thaIl compositions ~dded via the dispensirlg compartment of
a washing machine because, in the initial stages of a wash cycle, the
agitaltion in the immediate envi~nmen~ of the product is inhibi~ed by
~he presenGe o the fabric load. Whilst this ca~ co~stitute a beIlefit i~ :~
permi~cing ~e development of high transient conce~trations of
~ilder and surfactant, the development of high tr~siellt peroxyacid
concen~ra~iorls can, as noted previously~ lead to ~abric arld colour
damage. The coated peroxyacid bleach precursor particulates of the
present i~vention, when incorporated into conce~trated detergent
products delivered to the wash liquor via a dispensing deviee,
mitigate if not eli~ate this problem.
Detergent compositions ineorporating the surface treated peroxy ~cid
bleach precursor particulates will normally eontain from 0.5 % to
10~ of the precursor, more frequently ~rom 1% to 8% and most
preferably from 2% to 6%, on a composition ~veight basis.
2101~
W~ 92/137g8 P~/US92/00664
Such detergent compositions will, of course, contain a source of
alkali~e hydrogen peroxide necessa~y to form a pero~yacid bleaching
species in the wash solu~ion and prèferably will also contain o~her
components conve~ional in detergent compositions. Thus preferred
de~ergent compositions will incorporate o~e of more of surfactants,
org~c and inorg~c builders, soil uspendi~g and ~nti-redeposition
agents, suds suppressors, e~zymes, fluoresce~t whitening age~ts
photo ac~iva~d bleaches~ perfilmes a~d colours.
Detergent compositions incorporating the surface treated particulate
peroxyacid precursors of the present inve~tion will include ~
i~orga~ic perhydrate bleach, normally in the fo~ of the sodium salt,
as the source of alkal~e hydrogen peroxide i~ the wash liquor. This
perhydrate is normally ~ncorporat~ at a level of ~rom 3 % to 22% by
weight, more preferably ~rom 5% to 20% by weight and most
pre~erably ~rom 8% to 18% by weight of the compo~itio~.
The perhydrate may be a~y of the inorganic salts sueh as perborate
percarbonate, perphosphate a~d pcrsiLicate salt~ but is conYeIl~ioIlally
an a~ali metal perborate or percarbonate. Whilst fabric coiour
damage arising ~rom compositions in accordance with the invention
is low, irrespective of whether a perborate or percarbonate salt is
employed, the improvement in comparison with u~coated precursor
pa~ticula~es is more noticeable wi~h percarbonate bleach as this
causes greater fabric colour damage in ~he absence of any coati~g on
the bleach precursor.
Sodium percarbonate, which is the preferred perhydrate, is an
addition conllpound havi~g a fo~mula correspo~ding to
2Na~CO3.3H202, aIld is available commercially as a crystalline
solid. Most commercially available material includes a low level of
a heavy metal sequestrant such as EDTA, 1-hydro~yethylidene 1, 1-
diphosphonic acid (HEDP) or an an~ino-phosphonate, that is
incorporated during the ma~ufacturing process. For the purposes of
the de~ergent composition aspect of the present invention, the
percarbonate can be incorporated into detergent compositions without
additional protection, but preferred executions of such compositions
~101~(18
VO 92/137g8 PCI`/US92/0066
11
utilise a coated form of the material. Although a variety of coatings
can be used, the most economical is sodium silicate of SiO2:Na20
ratio from 1.6:1 to 3.4:1, pre~erably 2.8:1, appli~ as an aqueous
solution eO give a level of ~rom 2~ to 10~, (normally ~om 3% ~o
5 %) of silicate solids by weight of the percarbonate. Magnesillm
silicate can also be included i~ the coating.
The par~icle size ra~ge of the &ryStalliIle perca~onate is ~rom 350
micrometers to 450 micrometers with a mean of appro~imately 400
micrometers. When çoated, the crystals have a size in the range from
400 to 600 micrometers.
Whilst heavy metals prese~t in the sodium carbonate used to
manufacture the perearbonate can be controlled by the i~clusio~ of
sequestrants in the reaction ~xture, tbe percarbonate still requires
proteetiorl from heavy metals ~rese~t as i~purities in other
ingredients of the product. According]ly, in detergent compositions
u~ilising percarbollate as the perhydrate salt, the tot~l level of Iro~,
Copper and Ma~ga~ese ions i~ the pro~ucl: should not e~ceed
25 ppm and preferably should be less thall 20 ppm in order to avoid
an unacceptably adverse e~ect on percarbonate stability. Detergent
compositio~s in which alkali metal percarbo~ate bleach has enhanced
s~ability are disclosed i~ ~he ~pplica~ts copeIld~g British Pateng
Applica~ion No. 9021761.3 (Attorney's Docket No. CM343).
A wide range of sur~actants ca~ be used in the dete~ent
composi~îo~s. A typical listi~g of anionic, ~o~ionic, ampholytic and
zwi~erionic cl~sses, and species of these surfactants~ is given in
U.S.P. 3,929,678 issued to Laughlin a~d HeuriIlg on D cember, 30,
1975. A list of suitabl~ cationic sur~ac~a~ts is given i~ U.S.P.
4,259,217 issued to Murphy on March 31, 1981.
Mixtures of anionic surfactants are suitable herein, partieularly
blends of sulphate, sulpho~ate andlor c~rboxylate surfac~ants.
Mixtures of sulphonate and sulphate sur~actants are normally
employed ~ a sulphonate to sulphate weight ratio of from S:1 to 1:2,
preferably from 3:1 to 2:3, more preferably from 3:1 to 1:1.
2 1 0 ~
WO 92t~3798 P~/US92~00664
12
Preferred sulphonates iDclude alkyl benzene sulphona~es havi~g from
9 to 15, especially 11 to 13 carbon a~oms i~ the alkyl radical9 and
alpha-sulphonated methyl ~atty acid esters in which the ~atty acid is
derived from a C12-(: 18 i~atty source9 preferably ~rom a C16-Clg
~atty source. In each instance the catio~ is an alkali metal,
preferably sodium. Preferred sulphate sur~actalats i~ such sulphonate
sulphate mi~tures are alkyl sulphates havillg ~rom 12 to 22,
preferably 16 to 18 carbo~ atoms in thç alkyl radical. Another use~ul
surfactant system co~pnses a ~x~ure of two alkyl sulphat~ materials
whose respective mean chain lengths dif~er from each o~her. C)ne
such sygtem comprises a mi~t~re of C14-Cls alkyl sulphate and
C1~-C1g alkyl sulpbate in a weight ~atio Of (~14-6~15: C16-(~18 of
~-~ from 3:1 to 1:1. The allyl sulpha~ may also be combLned with
alkyl ethoxy sulphates havin~g ~rom 10 to 20, preferably 10 to 16
carbon aeoms in the alkyl radical ~d a~ average degree of
ethoxylation of l to 6. The catîon in each iIIstanc is aga~n an alkali
metal, preferably sodium.
C)ther ~ionic surfactants suitable for the purposes of the illvention
are the al~li met~l sarcosina~es of ~ormula
R-CON ~R) CH~ COOM
whe~ R is a Cg-C17 linear or brallched alkyl or alkenyl group, R'
is a C1-C4 alkyl group a~d M is an alkali metal ion. Preferred
exa~nples are the lauroyl, Cocoyl (C12-C14), myristyl and oleyl
me~yl sarcosinates in the form of their sodium salts.
One class of nonionic sur~actants useful in the present inYention
comprises condensates of ethylene o~cide with a hydrophobic moiety,
providing sul~ac~ts having an average hydrophilic-lipophilic
balance (HLB) in the range from 8 to 17, preferably from 9.S to
13.5, more preferably ~rom 10 to 12.5. The hydrophobic (lipophilic)
moie~y may be aliphatic or aromatic in ~ature a~d the }ength of the
polyo~yethylene group which is condensed with any particular
hydrophobie group can be readily adjusted to yield a water-soluble
compound having the desired degree of balance betvveen hydrophilic
and hydrophobic elements.
~101~
~o 92/1379~ P~r/lJss2/00
13
Especially pre~erred no~onic surfactants of this type are the Cg-C1s
primary alcohvl ethoxylates contai~ing 3-8 moles of ethylelle oxide
per mole of alcohol, particularly the C14-C1s primary alcohols
con~g ~8 moles of ethylene o~cide per mole of alcohol and the
C12-C14 primary alcohols containin~ 3-5 moles of ethylene o~cide
per mole of alcohol.
Another class of nonionic sur~actants comprises al~l polyglucoside
compounds of general ~rmula
nH~n~)tzx
wherein Z is a moiety derived from glucose; R is a satura~ed
hydrophobic allyl group ~hat contains from 12 to 18 carbo~ atoms; t
is from O to 10 ~nd n is 2 or 3; x is from 1.3 to 4, the compou~ds
includ~g less than lO~o unreacted ~atty alcohol and less th~ 50~o
short chain alkyl polyglucosides. Com~ounds of ~his t~rpe and their
use i~ detergenl: compositions are disclosed in EP-B ~70074,
0070077, 0075996 and 0094118.
A ~urther class of sur~actants are the se~-polar surfactants such 2S
axr~ine oxides. Suit~ble amine ~xides are selected from mono
Cg-C20, pre~rably Cl~C14 N-al~yl or all~enyl a~e oxides and
propyl~ne-l ,3~iamine dio~cides wherein the remaini~g N positions
are substituted by methyl, hydro~yethyl or hydroxpropyl groups.
Ca~ionic surfactants can also be used in the detergent compositions
herein a~d suitable quaternary ammonium sur~ar-tants are selected
from mono Cg-C16, preferably Clo-C14 N~alkyl or alkenyl
ammonillm sl;arfac~a:nts wherein remaining N positions are substituted
by methyl, hydroxyethyl or hydroxypropyl groups.
The detergent composition comprise from 5% to 20~a of surfactan~
bu~ more usually comprise from 7% to 20%, more preferably from
10% to 15% surfactant ~y weight of the compositions.
~0 92/137~8 2 i 01~ A 8 PCI`/US~2/0066~ '
14
Combinations of sllrfac~Ilt types are pre~erred, more especially
anio~ nonionic alld also anionië-nonio~ic-cationic blends.
Particularly preferred combinatio~s are described in C3B-A-2040987
and EP-A 0087914. Although the su~facta~ts can be incorporated
into ~he compositions as mixtures9 it is preferable to control the point
of addition of each sur~a~tant in order to optimise the physical
characteristics of the co~nposition aIld avoid processL~g problems.
Preferred modes and orders of surfactant addition are described
hereina~er.
AIlogher highly pre~erred component of deterge~t compositioIls
incorporating the coa~ed peroxy acid precursor particulates of ~be
inve~tio~ is a deterge~t builder system compnsing one or more non-
phosphate de~ergent bl~ilders. Thçse can include, but are not
res~ricted to alkali metal carbonates, bicarbonates, silicates9
alu~osilicates~ mo~omeric polycarbo~ylates, homo or copolymeric
polycarboxylic acids or their salts in wh;ch the polycarbo~ylic acid
comprises at least two carboxylic r~di~als separated from each other
by not more tha~ ~wo carlbon atoms, organic phosphona~es a~d
aminoalkylene poly (alkylene phosphonates) aIld mi~tures of a~y of
the ~regoing. The builder system is present in an amount of iF~om :~
25% to S0~6 by weight of the c~mposition, more pre~rably ~rom
30~ to 60% by weight.
Pre~erred builder systems are free of boron compounds and any
polymeric organic materials are pre~erably biodegradable.
Suitable silicate are those having an SiO2:Na2Q ratio in the range
from 1.6 to 3.4, the s~called amorphous silicates of SiO2: Na~O
ratios from 2.0 to 2.8 being preferred. These materials can be a~ded
at various points of the manufacturing process, sueh as in a slurry of
componen~ that are spray dried or in the form of an aqueous
solution seirvin~ as an agglome~ating agent i~or other solid
components9 or, where the silicates are themselves in particulate
form, as solids to the other particulate components of the
compositon. H~wever, for compositions in which the percentage of
2.~ 8
~10 92/13798 PC~/U~9~/00664
spray dried col~pone~ts is low i.e. 30%, it is preferred to include the
amorphous silicate i~ the spray-dried compongnts.
.
Within the silicate class, highly pre~erred materials are crystalline
layered sodium silicates of general formula
NaMSi~O2x+ l-Y3H2~)
whereill M is sQdium or hydroge~, x is a number ~rom 1.9 to 4 and y
is a ~umber from 0 to 20, Crystalli~e layered s~illm silica~es of this
type are disclosed ~ EP-A~164514 aIld methods for their
preparatio~ are disclosed i~ DE-A-3417649 and DE-A-374~043. For
the purposes of the presen~ i~velltio~, x in l~e ge~eral for~ule above
has a value of 2, 3 or 4 a~d is preferably 2. More pre~erably M is
sodium arld y is 0 and pre~erred examples of this for~ula comprise
the ~ and ~ forms of Na~Si2Os. These materials are available
&om Hoechst AG FRG as res~ectiYely NaSKS-11 and NaSK5-6.
The most preferred material is -Na2Si~Os~ (NaSKS-6).
C: rystalline layered silicates are i~corporated either as dry mixed
solids, or as solid component:s of agglomerates with other
components. :
Whilst a r~nge of aluminosilicate ion e~cha~ge materials can be
used, preferred sodium aluminosilicate zeolites have the unit eell
formula
N~z [(~1~2 ) z (5i02 )y ~ ~H 2
wherein z arld y are a~ leas~ 6; ~he molar ratio of ~ to y is ~rom 1.0 to
0.5 a~d x is at least 5, pre~erably from 7.5 to 276, more pre~erably
from 10 to 264. The alumino~ilicate materials are in hydrated form
and are pre~erably crystalline, containing ~rom 10% to 28%, more
preferably from 18% to 22% water in bound form.
The above alumi~osilicate ion excha~ge materials are further
characterised by a particle size diameter of from 0.1 ~o 10
micrometers, preferably from 0.2 to 4 micrometers. The term
"particle size diameter" herein represents the a~rerage particle size
diameter of a given ion e~change material ~s deter~ined by
conventional analytical techniques such as, ~or example, microscopic
WO 92~13798 2101 4 ~ ~ PC~/US92/01)6M
16
determination utili~ing a scannir~g electron microscope or by means
of a laser granulometer~ The aluminosilicate iOIl excharlge materials
are further characterisecl by their ~alcl~m iOIl exchange capacity,
which is at least 2~0 mg equivalent of CaC03 vvater hardness/g of
aluminosilicate~ calculated on an anhydrou basis~ and whieh
generally is ~ the range of from 300 mg eq./g to 352 mg eq./g. The
aluminosilicaee io~ e~;cha~gg materials herein are still filrther
characterised by their ealeium ion e~change rate which is at least 130
mg equivalent of CACO3/litre/minute/(g/litre) ~2 grains (: a+ +/
gallo~ u~e/gram/g2110n)] of alu~osilicate (anhydrous basis)~
and which ge~erally lies withi~ the range of from 130 mg equivalent
of CaC03/litre/minute/(gram/litre) [2 ~grains/gallontminute/ :-
~ram/gallon)] to 390 mg equivalellt of CaC03/litrgJminute/ ~:~
(gram/litre) [6 grains/gallon/mi~ute/~gram/gallon)], based on calcium ~::
ion hardness. -:
Optimum aluminosilicates for builder purposes exhibit a calcium ion
exchange rate of at le~st 260 mg equivaleIlt of CaC03/litre/ minute/
(gram/litre) [4 grains/gallon/minute/(gram/gallon)~.
AlumiI~osilicate ion exchange materials use~ul in the practice of this
inven~ion are commercially aYailable and can be naturally occurring
materials, but are prefer~bly synthetically derived. A method for
producing aluminosilicate ion e~chaIlge materials is discussed in IJS
Patent No~ 3,985,669. Preferred synthetic crystalline alumiIlosilicate
ion e~change materials useful herei~ are available under the
desig~ations Zeolite A, Zeolite B, Zeolite X, Zeolite HS and ~:
mi~ res thereof. In a~ especially pre~erred embodiment, the ~:~
c~ystalli~qe alun~inosilicate ion excbange material is Zeolite A and has
the formula
~ 12 ~(A102 ) 12 (sio2)~2 ~. X~2
wherein x is ~rom 20 to 30, especially 27 Zeolite X of formula
Na86 [(A12)86(Si2)106] 276 H20 is also suitable, as well as
Zeoli~e HS of formula Na6 [(A102)6(SiO~)6] 7.5 H~ 0).
2101~
~/0 92/13798 P~/OS92/00664
17
Suitable water-soluble monomeric or oligomenc carboxylat~ builders
can be selected from a wide range of comp~u~ds but such
compounds pre~rably have a first carbo~yl logarithmic
acidity/constallt (pKl) of less ~an 9, pre~rably of between 2 a~d
- 8.5, more preferably of bet~Neen 4 and 7.5.
The logarithmic acidity constant is defined by reference to the
equilibrium
H+ + A =lEI+A
where A is the fully io~ized car~o~ylate anio~ of the ~ilder s~lt.
~-~ The equilibrium constant as therefore
K1 -- (H+ A)
I(H~) (A)
and pK1 = log~
For the purposes of this specification, acidity cons~ants are defimed at
25C a~d a~ zero ionic strength. Literature values are talcen where
possible (see Stability Cons~ts of Metal-Ion Complexex, Special
Publication No. 25, The Chemical Society~ London~: where doubt
arises ~hey are determined by potentiometric ti~ation using a ~glass
eleetrode.
Pre~rred carboxylates can also be defined in ~erms vf their calcium
ion stability cons~nt (pR~a~ ~) defined, a~alogously to pKl, by the
equatio~s
PKCa~ ~ logl0~Ca~ +
where ~Ca+ + (Ca~ + A)
(Ca+ +~ (A)
Preferably, the polycarboxyla~ has a pK C~a+ + in the range ~rom
abou~ 2 to about 7 especially from about 3 to about 6. Once again
2 1 ~ 8
~N~ 92/13798 P~/US92/0
18
literature values of stability constant are taken where possible. The
stabili~y co~stant is defilled at 25C and at zero io~ic stre~gth using a
glass electrode method of measurement as described i~ Co~plexation
in Analytical Chemistry by ~ders Ringbom (1963).
The carbo~ylate or polycarbo~cylate buailder c~ be momomeric or
oligomeric i~ type although mosomeric polycarbo~cylates are
generally pre~erred for re~o~s of cost a~d perfor~se~
Monomeric and oligomeric builde~s can be selected ~rom acyclic,
alicyclic,-heterocyclic and aromatic carbo~ylates havill the ge~eral
~ormulae ~:
~ .
( a ~
Rl --X~C- ~2
2 m
(b)
o~
(c) Yp~q
whe~ein Rl represents H,C1 30 all~l or alkenyl optio~ally
substitutKI by hydroxy, car~o~y, sulfo or phosphono groups or
attached to a polyethyle~o~cy moiety contai~i~g up to 20 ethyle~eoxy
groups; R~ represe~ts H,C1~ alkyl, alke~yl or hydro~y alkyl, or
alkaryl, sulfo, or phosphono gro~.lps;
X represents a single bo~; C); S; SO; SO2; or NRl;
Y represe~ts H; carboxy;hydro~y; carbo~methylo~cy; sr
C ~ 30 alkyl or alk nyl optio~ally substituted by hydru~y or carbo~cy
groups;
Z represen~s H; or carbo~cy;
vo 92/l37g8 2 1 0 1 ~ '1 8 P~r/USg2/00~64
19
m is an ~teger from 1 to 10;
n is ~ integer from 3 to 6;
p, q are i~egers from 0 to 6, p ~ q being from 1 to 6; and wherein,
X, Y, and Z each have the same or dif~rent represe~tations when
repea~ a given molecular formula1 and wherein at least o~e Y or
Z in a molecule contain a carboxyl group.
Suitable car~o~ylates co~ta~g o~e carbo~ group include lactic :~
acid, glycolic ~cid and ether derivatives thereof as disclosed i~
Belgian Patent ~os. 831,368, 821,369 and 821,370.
Polycarboxylates con~aining two carbo~y groups include ~e water-
soluble salts of succinic acid, malonic acid,, (etlhylenediQxy) diace~ic
~cid, maleic acid~ diglyeolic acid, tartaric acid7 tart~o~ic acid and
fumaric acid, as well as the ether carbo.xylates described iIl German
Of~e~legen~chrift 2,446~686~ and 2,446,687 a~d U.S~ Pate~t No~ -
3,935,257 and the sulfinyl carbo~ylates descri~ed in E~elgian Patent
No. 840,623. Polycarboxylates co~taining three carbo~y groups
iIIclude, iIl parti~ular, water-soluble citlates, aco~itra~es and
citraconates as well as succinate derivatives such as the
carboxymethyloxysuc~nates described in I3ritish Pate~t No.
1,379,241, lacto~cysucci~ates described in British Patent No.
1,389,7329 a~d a~osuccinates described in Netherlands
Application 7205873, and the o~cypoly~arboxylate materials such as
2-oxa-1,1,3 propane trica~o~ylates described ill British Patent No.
1,387,~47.
Polycarbo~ylates con~ining four carbo~cy groups incldue
oxydisuccinates disclosed i~ E~ritish Patent No. 1,261,829, 1~1J2~2
ethane tetracarboxylates, 1,1,3,3-propane tetracarbo~ylates and
1,1 ,2,3-propane tetracarboxylates. Polycarb~cylates contai~ing sul~o
substituents include ~e sul~osuccinate derivatives disclosed in British
Pate~t Nos. 1,398,421 and 1,398,422 and ~ U.S. Patent No.
- 3,936,4489 and the sulfo~ated pyrolysed citrates described in British
PatentNo. 1,439,000.
Alicyclic a~d heterocyclic polycarboxylates include eyclopentane-
cis,eis,cis-te~racarbo~ylates, cyclopentadienide pentacarboxylates,
21a~!l4~
WO 92/13798 PCI~/US92/00664 !
2,3,4,5-te~rahydro:fura~ cis, cis, cis-tetracarboxylates, 2,5-
tetrahydrofuran- cis - dicarboxylates, 2,2,5,5-tetrahydrofu~
tetracarbo~cylates, 1,2,3,4,5,~he~ e - he~ac~rbo~ylates and
carboxymethyl derivatiYes of polyhydric alcohols sueh as sorbitol,
ma~itol alld xylitol. Arolnatic polycarbo~ylates include mellitic
acid, pyromellitic acid and ~he phthalic acid deriva~ives disclosed in
British P~tent No. 1,4259343.
Of the above, the preferred polycarbo~cylates are
hydro~ycarbo~ylates con~g up to three carboxy groups per
molecule, more partieularly citrates.
The parent acids of the mo~omeric or oligomeric polycarboxylate
_. chelating a~e~ts or miactures thereof with their salts, e.g~ cit~c acid
or citrate/citric acid ~tures are also contemplated as components of
builder systems of d~erge~t compositions in accordance with the
preseIlt invention.
Other suitable water soluble orgaDic sal~s are the homo- or co~
polymeric pollycarboxylic acids or their salts in which the
polycarboxylic acid comprises at least two carboxyl radicals
separated from each other by not more than two carbon atoms.
Polymers of the latter type are disclosed in GB~A-1,596~7$6.
Examples of such salts are polyacrylates of MWt 2000 5000 aIld
their copolymers with maleic anhydride~ such copolymers having a
molecular weight of from 20,000 to 70,000, especially ab~ut 40,000.
These materials are normally used at levels of from 0.5% to 10~o by
weigh~ more preferably ~rom 0.75% to 8%, most pre~erably ~om
1% to 6% by weight of the composi~ion.
Organic phosphonates and amino alkylene poly (alkylene
phosphonates) inclu~e alkali metal etha~e l-hydroxy diphosphonates,
nitrilo trimethylene phosphorlates, ethylene diamine tetra methylene
phosphonates and diethylene triamine penta methyleIle phosphonates,
although these materials are less preferred where the minimisation of
phospborus eompounds in the compositions is desired.
2~01~sll~
Vl~g2/13798 PClfUS92~0~664
2'
~or the purp~ses of detergent compositions embodying the surface
tr~ated bleach precursor particulates of the i~vention ~ the non-
phosphate builder ingredient will comprise from 25% to 60% by
weight of the compo~itio~s, more preferably from 30% to 60% by
weight. Within the preferred compositions, sodium aluminosilicate
such as Zeolite A will comprise from 20% to 60% by weight of the
total amount of builder, a monomeric or oligomeric carboxylate will
comprise ~rom 10~ to 305to by weigbt of ~e total amou~t of builder
and a crystalline layered silicate will eomprise from 10% to 65% by
weight of the total amount of builder. I~ sueh compositions the
builde~ i~gr~ilen~ preferably also incorporates a coEnbi~atio~ of
auxiliary inorg~c aDd organic builders such as sodium carbonate
and maleic anhydride/acrylic acid copolymers in amo~ts of up to
35 ~o by weight of the total builder.
A~ti-redepositioIl and soil-sus~e~sioIl age~ts suitable herein ~clude
cellulose deriYatiYes such as rnethylcellulose~ carboxymethylcellulose
and hydroxyethycellulose, and homoo]r co~polymeric polycarboxylic
æids or their salts. Polymers of this type include copolymers of
malcic anhydride with ethylene, nnethylvinyl ether or methacrylic
acid, the maleic anhydride constituting at least 20 mole percent of the
copolymer. These materials are ~ormally used at levels of ~orn
0.5% to 10% by weight, more preferably from 0.75% to 8%, most
preferably from 1 5~o to 6~ by weight of the composition.
Other useful polymeric materials are the polyethylene glycols,
particlllarly those of molecular weight 1~10000, more particularly
2000 to 8000 and most preferably about 4000. These are used at
levels of from 0.20~ to 5% more preferably from 0.25% to 2.5%
by weight. These polymers and the previously mentioned homo- or
eQ-polymeric polycarbo~ylate salts are vaïuable for improving
whiteness mainte~a~ce~ fabric ash depositiorl, and cleaning
performance on clay, proteinaceous and oxidi~ble soils in the
prese~ce of transition metal impurities.
Preferrecl optical brighteners are anionic in charaeter, examples of
which are disodium 4,41-bis-(2-diethanolamino~anilino -s- triæin-
21~ l8wo ~/13798 PCI`/USg2/~0664 ' -
22
ylamino)s~ilbene-2:21 disulphonate, disodium 4,41~bis-(2-
morpholino ~aniliI1~2-~riazin-~ylaminos~ilbene-2:2l-
disulphonate,disodium 4, 41-bis-(2,4 dianilin~s-triæi
ylamino)stilbe~e-2:21 - disulpho~ate, mo~osodlium 41,411-bis-(2,~
diaI~ili~s-~ 6ylamiIlo)seilbene-2~ sulpho~ate, disodium4,41
bi~-~2-al~ili~o~(N-methyl-N-2-~ydro~yethyl~o3-2-triaz~Il-
~ylamino)stilbe~e 2,21 ~ disulphonate, disodium 4,41-bis-~phenyl~
2,1,3-triazol-2-yl)stilbe~e-2,21 disulph~ disodium4,41bis(2-
a~lino~(l-methyl-2-~ydro~yethylamino)-s-triazin-
~yl~o)stilbe~e 2,21disulpho~ate a~d sodium 2(stillb~
~n~aphth~11 ,21 :4pS)-1,2,3 - ~azole-21 1 sulphoIla~:
Soil-relea~e agents usefi~ compositio~s of the prese~ invention
are con~entionally copolymers or terpoly~ers of terephthalic acid
wîth ethylelle glycol a~d/or propyle~e glycol unîts Ln varîous
arra~geme~ts. I~ples of s~ch pol~ers are dîsclosed ~ the
commonly assigned US Pate~t Nos. 4116885 ~d 4711730 a~d
Europea~ Publîshed Patent ApplîcatîoDI No. 0272033. A partîcular
prei~erred polymer in accordance wîth EP-A~272033 has the ~ormula
3(~a~43~O.7~ .a5t~ a.~ )o.d~ os-asop~G~3c~3)o-75
Certain polymenc ~enals such as polyvî~yl pyrrolidones typîcally
of MWt 50~20000, preferably 10000 15~, also form useful
agen~s in preven~i~g ehe tra~sfer of labile dyestu~fs be~wee~ ~abrics
dur~g ~e washî~g process.
Another optional detergen~ composition i~gredîe~t is a suds
suppr@ssor, e~cemplified by silico~es, a~d sîlica-sîlieo~e mi~ctures~
Sîlicones can be ge~erally represented by alkylat~d polysilo~e
matenals whil~ silica is ~srmally us~ finely divided ~orms~ -
e~emplified by sîlica aerogels and xerogels a~d hydrophobic sîlicas
of various types. These matenal~ ca~ b~ incorporated as partieulates
i~ which the suds suppressor is advantageously releasably
incorpora~:ed in a water-soluble or water~îspersible, sub~tantially
2101 ~
0 92/13798 PCr/US92/0066
~3
non-surface-active detergent-impermeable carrier. Alternatively the
suds suppressor can be dissolved or dispersed i~ a liguid carrier a~d
applied by spraying on to one or more of the other com~onents.
As men~ioned above, usefill silicone suds controllillg ageIlts can
comprise a mi~cture of an alkylated silo~ane, of the ~pe referred to
hereiIlbe~ore, ~d solid silica. Such mi~ture~ are prepared by
~ffixing the silicone to the surface of the solid silica. A preferred
silicone suds controlli~g age~t is represented by a hydrophobic
sila~ated ~most preferably trimethyl-silaD ated~ silica hav~g ~ particle
size in the range from 10 na~ometers to 20 ~ometers and a speGifi~
surface area above 50 m21g~ intimately admi~ed with dimethyl
~-~ silico~e fluid having a molecular weight i~ the ra~ge ~rom ab~ut 5
to about 200,000 at a weight ratio of silico~e to silanated silica of
~rom ab~ut 1:1 to about 1:2.
A preferred silicone suds controlling a~gent is disclosed in Bartollo~a
e~ al. US Paterlt 3,933,672. Other parlicularly u~efill suds
suppressors are the sel~-emulsi~ying silicone suds suppressors,
described in (3erman Patent Application Dl'OS 2,646,126 published
April 28, 1977. An example of such a compound is :0C0544,
commercially available from Dow Conning, which is a
siloxane/glycol copolymer.
The suds suppressors described above are ~ormally e~ployed a~
levels of ~rom 0.001% to 0.5% by weight of the composition,
preferably from 0.01% to 0.1% by weight.
The pre~rred methods of incorporation comprise either application
of th~ suds suppressors in liquid form by spray-oll to one or more of
~h~ major components of the compositioll or alternatively the
formation of the suds suppressors L~to separate particulates that can
the~ be mi~ed with the other solid com~onents of the composition.
The inc~rporation of the suds modifiers as separate particulates also
permits the iIlclusion ~herein of other suds co~trolling materials such
as C2~C24 fatty acids, microcrystalline waxes and high MWt
copolymers of ethylene oxide and propylene oxide which would
WO 9~/13798 2 1 0 1 ~ '1 g P~/US92/~06~4 ~
24
otherwise adversely affect the dispersibili~ of the matrix.
Techniques ~or forming such suds modifying particulates are
disclosed in the previously mentioned Bartolo~ et al US Patent No. ~:
3,933,672. ::~
Another optional i~gredient useful in the present i~ventio~ is one or
more enzymesO
Prei~err~ en~ym~ic materials i~clude the con~ercially a~ailable
amylases, n~u~al ar~d al~aline proteases, lipase~, esterases a~d
cellulases conventionally i~corporat~ into detergent eo~positions.
Sui~able e~ymes are discussed i~ US Pate~ts 3,519,570 and
3,S33,139.
~abric softenin~ agents can also be ~corporated into detergent
co~positio~s i~ accorda~ce wi~ the present i~vention. Thes~ agents
may be inorga~iG or organic iIl typeO Inorganic softe~in~g agents are
e~amplified by the smectite clays disclosed in G13-A-1,~,898.
Orgaruc ~ric so~tening age~ts include the water i~soluble tertiary
amines as disclosed in GB-A-1514276 ~md E~P-B-00l 1340.
Their combiDation with mono C12-Cl~ quater~ary ammonium salts
is disclosed in E~P-B~2~527 ~ 528. Other use~ul or~ganic ~a~ric
softening age~s are the dilong chain a~ides as disclosed in EP~B-
0242919. Additional org~c ingredients of fabric softening sys~erlls
include high molecular weight polyetlhylene o~;ide ~aterials as
disclosed in EP-A-0299575 and 0313146.
Levels of smectite clay are normally in the range from 5% to lS~,
morc pre~rably from 8% to 12~i by weight~ with the material being -~
added as a dry mixed component to the remainder of the ~orn~ulatio~
Org~c fabric softe~ing agents such 2s the water-insoluble tertiary
amines or dilong chain amide materials are incorporated at levels of
from 0O5 % ~o 5 % by weight, normally ~rom 1% to 3 ~ by weight,
whilst the high molecular weight polyethylene oxide materials ~nd
the water soluble cationic materials are added at levels of from 0.1
~o 2%, normally from 0.15% to 1.5% by weight. Where a portion
2 1 ~
~0 92/13798 P~r/U~92/00664
of the composition is spray dried, these materials can be added to the
aqueous slurry ~ed to the spray drying tower, although in some
i~stances it may be more ~o~venient to add them as a dry mixed
par~iculate, or spray ~hem as a molteIl liquid o~ to o~her solid
components of the composition.
The surface treated pero~yacid bleach precur~or particulates of the
present invention are par~icularly usefill ~ co~ee~tra~ed gra~ular
detergent compositions that are characterised by a relatively high
densi~ compariso~ with col~ventional laundry detergent
compositio~s. Such high de~sity composi~ons have a bulk de~sity
of a~ leas~ 650 g/litre, m3re usually at least 7~ g/litre and more
~-~ pre~erably i~ excess of 800 g/litre.
Bulk d~nsity is measurecl by means of a simple ~ el and cup deviçe
co~sisti~g of a conical fuDIlel moulded rigidly o~ a lbase and provided
with a flap valve at its lower e~tremity to allow the conte~ts of the
fu~el ~o be emptied i~to an a~cially alig~ed cyli~drical cup disposed
below tbe filDnel. The ~u~nel is 130 mm and 40 mm a~ its respec~ive
upper alad lower extremities. It is mounted so that the lower
ex~remity is 140 mm above the upper surface of th~ base. The cup
has an overall beight of 90 mm, ~ i~ter~al height of 87 m~ and a~
inten~al diameter of 84 mm. I :s nominal volume is 500 ml.
To carry o~t a measureme~t, the funn~l is filled with powder by
hand pouring, thc flap valve is opened and powder allowed to
overfill the cup. The filled cup is removed from t:he frame and
excess powder removed from ~he cup by passing a straigh~ edged
implemen~ e.g. a kni~e, across its upper edge. The filled eup is then
weighed and ~he ~alue obtained for the weight of powder doubled to
provide the bulk density in g/litre. Replicate measurements are made
as required.
Concentrated detergent compositions also normally incorporage at
least one mul~i-ingredie~t component i.e. they do not comprise
compositions formed merely by dry-m~xing individual ingredients.
Composi~ions in which each individual ingredient is dry-mixed are
WO 92/1379~ 210 ~ 8 P~JVS92~00664
26
generally dusty, slow to dissolve and also tend to cake and develop
pOOF par~icle flow characteristics in storage.
Sub3ect to the above bulk densi~ and co~nponent co~tent limitatio~s,
the compositions of ehe inventio~ can be made via a ~arie~ of
me~hods includi~g dry mi~ing, spray drying9 agglomeration a~d
grarlulatio~ a~d prefe~ed methods i~volve combinations of these
tech~iques. A preferred method of making the co~positio~s
involves a eombina~io~ of spray drying, agglomeration in a high
speed mi~cer a~d dry mi~ing.
Pre~erred detergent ~ompositions in accordallce wi~h the invention
comprise a~ least ~wo particulate multi-in~gredient compone~ts. The
first componeIlt ~omprises at least 15 %, conYentionally ~rom 25 % ~o
50%, but more pre~erably ~o more thall 35~Zo by weight of the
composition an~ the seco~ compone~t ~rom 1% to 50% 9 more
pre~rably 10% to 40% by weight of the compositioIl.
The first compone~ comprises a par~iculate incorporating a~ anionic
surfacta~t ~ aIl amou~t of from 0.75% to 40% by weight of the
powder and one or more inorganic and/or orgaIlic salts in a~ almou~t
of from 99.25% to 60% by weaght of ~he powder. The par~iculate
ca~ have any suitable ~o~m such as gran~les, flakes, prills, maFumes
or no~dles but is preferably graIlular. The grallules ~hemselves may
be agglomerates formed by pan or drum agglomeration or by in~ e
mi~ers bu~ are customarily spray dried particles produced by a
atomising ~ aqueous slurry of the ~gredients in a hot air stream
which removes most of ~he water. The spray dried granules are then
subJected to densificatio~ steps, e.g. by high speed cutter mixers
and/or compacting mills, to increase density before bei~g
reagglomerated. For illustrative purposes, the first oomponeIlt is
described hereinafter as a spray dried powder.
Suitable anionic surfactants ~or the purposes of the first componeIlt
have bee~ ~ound to be slowly dissolving linear alkyl sulfate salts in
which the alkyl group has an average of from 16 to 22 carbo~ atoms,
and linear all~yl carbo~ylate sAlts in which the alkyl group has an
2101 ~'~8
,~o ~2/1379~ P~T/USg2/(~0664
27
average of from 16 to 24 carbon atorns. l'he alkyl groups for both
types of sur~actant are preferably derived ~om natural sources such
as tallow fat and marine oils.
The level of anionic surfactant iYl the spray dried powder ~rming the
first compo~ent is from 0.75~ to 40% by weight, more usually
2.5% to 25% preferably from 3~; to 20% aIld most pre~erably ~om
~% to 15% by weigh~. Water-soluble sur~ac~nts such as liIlear alkyl
be~æ~e sulphonate or C~4-C1s alkyl sulphates call be included or
alternatively may be applied subseque~tly to the spray dried powder
by spray o~.
~-~The o~er ma3or ingtedient of the spraS~ dned powder is one or more
inorg~c or organic salts ~hat proYide the crys~alline structure for
the graIIules. The inorganic alld/or org~c salts may be water-
soluble or wa~er-i~soluble, the laKer tg~e being comprised by the, or
the ma~or part of the, water-insoluble ~lilders where ~ese ~orm part
of the builder ing~edient. Sui~ble wate,r soluble ino~a~ic salts
include the alkali metal carbonates and ljicarbonates. Allcali metal
silicates other than crystalline layered silic~tes can also be present in
the spray dri~d gr~ule provided that ~luminosilicate does not ~rm
part of the spray dried component.
HoweYer, in ~oIlcentrated deterge~t compositio~s it is preferred that
water-soluble sulphate, particularly sodium sulphate, should not be
present at a level of more than 2.5% by weight of the composition.
Pre~rably no sodium sulphate is added as a separate ingredient and
its incorpolratio~ as a by-product e.g. with sulph(on)ated sllrfactants7
should be ~mised.
Where an aluminosilicate zeolite forms the, or part of the, builder
ingredie~, it is preferred that it is not added directly by dry-mixing
to the other components, but is incorporated into the multi~ gredient
compoIlent~s). Where incorporation of the zeolite ~kes place in the
spray~ried granule, any silicate present should not form part of the
spray~ried granule. In these circumstances, incorporatioll of the
silicate can be achieved in several ways, e.g. by producing a separate
.... ,, .. . , .. . . ~... ... .. . . . . . . .
WO92/137~8 Z~ 3 PCI`/US92/aO664 '
28
silicate-contail~ling spray-dried particulate, by incorporating the
silicate i~to an agglomerate of otlher ingredie~ts, or more pre~erably
by adding the silicate as a dry mixed solid i~gredient.
The first component ca~ also include up to 15% by weight of
miscellaneous ingredie~ts such as brighteners, a~ti-redeposition
agents, photoactivated bleaches ~such as tctrasulfonated zinc
phthalocyani~e) and heavy metal sequeste~ing ag~nts. Where the
first compo~ent is a spray dried powdgr it will no~ally be dried to a
moisture conteIIt of from 7 ~ to 11 æ by weiglht, more preferably
from 8% to 10% by weight of the spray dried powder. Mois~re
co~teIl~ of powders produced by other processes such as
~~ agglomeration may be lower and c~ be ~ the range 1~10% by
weight.
The particle size oP ~e first c~ponerlt is co~ventianal and
preferably not more than 5~o lby weight should be above 1.4mm,
while not more than 10~ by weight should be less than û.15 mm in
maxi~um dimension. Preferably at least 6Q~ d most preferably
at least 80%, by weight of the powder lies between 0.7 mm a~ 0.25
mm in size. Por spray dried powders, tlhe bulk derlsity of the
par~icles ~rom the spray drying tower is co~ventio~ally in the r~ge
from 54() to 6()0 g/li~e and this is then enhanced by fur~her
processing steps such as size reduction in a high speed cutter/mixer
~llowed by compactiorl. Alternatively7 processes other than spray
dryi~g may be used to ~rm a high density particulate directly.
A second compotlerlt of a preferred compositiorl in accordance with
the inventio~ is another r~ulti-ingredient particulate containing a
water soluble sur~actant.
This may be anionic, noniorlic, cationic or semipolar in type or a
mi~ture of any of these. Suitable surfactants are listed hereinbefore
but pre~rred surfactants are C14-Cls alkyl sulphates, linear Cll-
C~s alkyl benzeIle sulphonates and fatty C14-Clg methyl ester
sulphonates.
wo s2Jl37s~ 2 i O 1 ~ ~ 8 ~cr/uss2/00664
29
The seco:nd component may have any suitable physical ~orm, i.e. it
may take the form of flak~s, prills, marumes, noodles, ribbo~s~ or
granules which may be spray~ried or non spray~ried agglomerates.
Although the seco~d component could in theory comprise the water
soluble surfactant on its ow~ in practice at least one organic or
inorg~c salt is includ~ to facilitate processi~g. This provides a
degree of crystalli~ he~ce acceptable flow characteristics~ to
the particula~e and may be any o~e or more of the organic or
inorganic salts present in the first component.
The par~icle size range of the seco~d compo~e~ should be such as tn
obvia~e segre atio~ from the pa~icles of the first eomponent when
.~blended therewith. Thus not more than 5% by weight should be
above 1.4 mm while not more than 10% should be less th~ O.lS mm
in maximum dimensio~.
The bulk dgrlsity of the second component will be a ~unction of its
mode of preparation. However, the pre~erred form of the secorld
component is a mech~cally mi~ed agglomerate which may be made
by addi~g the ingredients dry or with arl agglomerati~g agent ~o a
pan agglomerator, Z blade mixer or more preferably an in-line mixer
such as those manufactured by Schugi (HollaIld) BV, 29
Chroomstraat 8211 AS, Lelystad, Netherlands and Gebruder Lodige
Maschi~enbau GmbH9 D~790 PaderborD 1, ElseIlerstrasse 7-9,
Postfaeh 2050 ~.R.G. By this mea~s the second componeIlt can be
given a bulk density ~ the range from 650 g/litre to 1190 g/litre
more preferably from 750 g/litre to 850 g/litre.
Preferred compositions include a level of alkali metal carbonate in
the second compo~ent corresponding to an amount of from 3 % to
lS~o by weight of t~e composition, more pre~rably *om 5% to 12%
by weigh~. This will provide a level of carbonate in the second
eompo~ent of from 20% to 40% by weight.
A highly preferred ingredient of the second component is also a
hydrated water insoluble aluminosilieate ion e~change material of the
synthetic zeolite type, de~cribed hereinbe~re, present at from 10~o
2101~8
wo 92/1379g Pcr/uss~/oo664 :
to 35% by weight of the second component. The amount of water
insoluble alu~osilicate material incorporated in this way is ~rom
1 ~Zo to 10% by weigh~ of the Gomposition~ more pre~erably from 2%
to 8~o by weight.
In one process ~or prepari~g ~he seco~d compone~t, the sur~ac~t
salt is formed in situ in a~ ~line mi~er. The liquid acid ~rm af the
surfac~t is added to a mi~cture of par~culate ~hydrous sodiunn
carbos~e and hydrated sodium aluminosilicate in a contin~ou~ high
speed blender, such as a Lodige KM mi~er, and neu~:ralised to form
the surfac~t salt whilst ma~ta~ the particulate sature OI the
mixture. The resultant agglomerated mi~cture ~orms the second
~-~ compone~t which is ~en added to other components of the product.
In a vanant of this p~ocess, the surfacta~t salt is pre-neu~alised and
added as a viscous paste to the mi~h~re of the other L~gredients. In
the variant, ~he m~cer serves m.erely to agglomerate ~he ~gredie~ts
to ~orm the second compo~ent.
In a particularly preferred ~rocess ~or malcing detergent compositions
incorporating the coated peroxyacid bleach precursor particulates of
~he inYention, par~ of the spray dried product comprising the first
granular component is diverted a~d subjected to a low level of
nonionic su~acta~t spray o~ before be~ng reblended with the
remai~der. The second gra~ular compohent is made using the
pre~err~d process described above. The first and second components
together wtth the coated bleach precursor particulate and the
perhydrate bleach, other dry mi~ i~gredients such as any carbo~ylate
chelati~g agent, soil-release polymer, silicate of co~ventio~al or
crys~all~ne layered type, and e~yme are then ~ed to a conveyor belt,
fro rn which they are transferred to a horizontally rotating dNm in
which perfume and silico~e suds suppressor are sprayed on to the
product. In highly pre~erred composi~ions, a further drum mixi~g
step is employed in which a low (approx. 2% by weight) ievel of
finely divided crystalline material is introduced to i~crease density
and improve grallular flow characteristics.
2101~48
NO 92/13798 P~/US92/00664
31
In preferred co~centrated detergent products incorporatin~g a~ alkali
metal percarbo~a~e as the perhydrate salt it bas bgen ~ou~ necessary
to co~erol several aspects of the product such as its heavy metal io~
co~te~t and its equilibrium relative humidi~ Sodium percarbo~ate-
co~tainî~g compositio~s of this type having enh~ced stabili~ are
disclosed in the commonly assigned British ~pplicatio~ No.
9021761.3 filed October 6 1990 Attorney's Doclcet No. (:~M343~
Compositions ~ accordance with the illvention caD also benefit from
delivery systems that provide tra~ient lo- alised high concelltrations
of produc~ in the drum of ~ ~ut~matic washing machine at the s~are
of the wash cycle~ thereby also avoiding problems associated with
31OSS of product ~ the pipework or sump of the mach~e.
DeliYery to the drum ca~ most easily be achieved by incorporation of
t~e composition in a bag or coIltainer from which it is rapidly
releasable a~ the start of ~e wash cycle i~ response to agitation, a
rise in te~perature or immersio~ e wash water in the drum.
AlternatiYely the washi~g mach~rle itself may be adapted to permit
direct addition of the composition to the drum e.g. by a dispensi~g
arrangeme~t in the access door.
Produc~ comprising a detergent composition enclosed i~ a bag or
cont~iner are usually designed in such a way that co~ er i~tegrity
is maintained i~ the dry state to prevent egress of the contents whe~
dry, l~ut are adapted f~)r release of the container contents on exposure
to a wa~ g environment, ~ormally on i~nersio~ in an ~queous
solution.
Usually the contaiDer will be flexible, sl~ch as a bag or pouch. The
bag may be of fibrous construction coated with a water impermeable
protecitive material so as to retain the contents, ~uch as is disclosed in
E~uropean published Pate~t Application No. 0018678. AlternatiYely
it may be formed of a water-insoluble synthetic polymeric material
provided with an edge seal or closure designed to rupture i~ aqueous
media as disclosed in l~uropean published Patent Application Nos.
0()11500, 01)11501, 0011502, and 0011968. A convenient form of
2 ~
WO 92/1379~ PCI/US92/006~i4
32
wa~er ~ra~gible closure eomprises a water soluble adhesive dispo~ed
along and seal~g one edge of a pouch formed of a w~ter
impermeable polymeric film such as polyethyle~g or polypropylene.
In a variant of the bag or container form, la~ted sheet produets
can be employed in which a central fle~ible layer is impregllated
and/or coated with a composition and then one or more outer layers
are applied to produce a fabric-like aesthetie effect. The layers may
be sealed together so as to remain attached during use or may
separate o~ contact wi~h water to ~acilitate the release of the coated
or impregnated material.
An alternative laminate form comprises one layer embossed or
~deformed to provide a series of p~llch-like co~ta~ers i~to each of
which the deter~nt somponeIlts are deposited in measured amounts~
with a second layer overlyi~g tlhe first layer and sealed thereto in
those areas beteen the pouch-like contai~ners where the two layers are
in co~tact. The compo~ents may be deposited in particulate, paste or
molten ~orm and the lami~ate layers should preveIlt e~ress of the
contents of the pouch-like containers prior to their additio~ to water.
The layers may separate or may remain attaehed together on co~tact
with water, the only re~uiremen~ being that ~he struc~ure should
permit rapid release of the contents o~ the pouch-like contairlers into
~olution. The ~umber of pouch-like containers per unit area of
substrate is a matter of choice but will normally vary between 500
and 25,000 per s~are metre.
Suitable materials which can be used ~or the fle~cible laminate layers
in this aspect of the invention include, among others9 sponges, paper
and wove~ a~d non-woveIl fabries.
However the preferred means of carrying out the process of the
mven~ioIl is to introduce the composition into the liquid surrourlding
the fabrics that are in the drum via a reusable dispensi~g device
having walls that are permeable to liquid but impermeable to ~he
solid composition.
2 1 01~8
VO 92/1379~ PCl/IJS92/00664
33
Devices of this kind are disclosed in European Patent Application
Publication Nos. 0343069 & û343070. The latter Applicatio~
discloses a device comprising a fle~cible sheath in the form of a bag
extending ~rom a support ring def~ing an orifice9 the orifice being
adapted to admit to the bag su~fice~t product or one washing cycle
in a washing cycle. A portioIl of the washi~g medi~m flows through
the orifice into the bag, dissolves the product, ~d the s~lutioIl then
passes outwardly through the orifice into the washing medium. The
suppQrt ring is provided wi~h a masking arraIlgement to preve~t
egress of wet~ed, Imdissolved, product, ~is arrangement typically
comprising radially extendi~g walls extending ~rom a ceneral boss in
a spoked wheel configuration, or a similar stmcture in which the
walls have a helical form.
The inventioll is illusgrated in the following non limiting Examples,
in which all percentages are on a weight basis u~less otherwise
stated.
WV ~2/13792 i ~ P~r/US92100664 .
34
In the detergent compositions, the abbreviated component
identifications have the ~llowing meanings:
C12LAS : Sodium linear C12 alkyl benzene
sulphonate
TAS : Sodium ~llow alcohol sulphate
C14115A~ : Sodium C14-( 15 allcyl sulphate
TAE~ : Tallow alcohol etho~sylated with n moles of
ethylene o~ide per mole of alcohol
45E7 : A Cl~ls p~onu~tly linear primary alcohol
_. condensed with an-average of 7 moles of ethylene
oxide
CnAFE6 S : A C12-C13 pnmary alcohol condensed with 6.5
moles of ethylene oxide.
PEG : Polyethyleneglycol (MWtnonnally follows)
TAED : Tet~aacetyl ethylene diamine
Silicate : Amorphous Sodium Silicate (SiO2:Na2O ratio
norrnally follows)
NaSKS-6 : Crys¢¢Lalline layer~d silica¢~e of formula
Na2Si20s
Carbon~¢e : Anhydrous sodium carbonate
CMC : Sodium carboxyme¢thyl cellulose
Zeolite A : Hydrated Sodium AlumiQosilica¢te of formula
Nal2(Al~SiO2)l2- 27~20
haYing a primary par~icle size in the ~nge from 1
to 10 micrometer~
PQlyacrylate : Homopolymer of acrylic acid of MWt 4000
Ci¢tra¢te : Tn-~dium ci¢¢~rate dihydra¢~e
2 1 ~
~VO 92~1~798 PCI~,~US92/00664
Photoactivated : Tetra sulphonated Zinc
Bleach phthalocyanine
MA/AA : Copolymer of 1:4 maleic/acrylic acid,
average molecular weight ab~ut 80,000.
MYEMA : Maleic anhydride/vi~yl methyl ether
copolymer, belieYed to have an average
molecular weight of 2409000. This material
was prehydrolysed wi~ NaOH before
addition.
Perborate : Sodiumperborate tetrahydrate of nominal
- ~or~ula NaB~.3~2o.~2o2
Perborate : Anhydrous sodium perbora~e bleach
~-~ Monohydrate empiri~al for~ula NaB02.EI20~
Percarbonate : Sodium Percarbonate of no~al formula
2Na2C03.3~1202
Enzyme : Mixed proteolytic a~d amylolytic
enzyme sold by Novo I~dus~ries AS.
l3rightener : Disodium 4,4'-bis(2-morpholiIlo~a~ilino-
s-triazin-~ylamino~ s~ilbene-2:2'-
disulphonate.
DETPMP : Dieth~ene triamine penta (Methylene
phosphonic acid), marke~ed by Monsanto
under ~he Trade l~ame Dequest 206
Mi~ed Suds : 25% para~f~ waxMptSOC, 17~
Suppressor hydrophobic silica, 58~o paraffin oil.
21(JlllL~3
WO 92/1379X PCI/U~;9~0066q
36
For the purpose of the presen~ invention, unrestrained dissolution
conditions are defined as those existing in the Beaker Perhydrolysis
Test as carried out USillg a Sotax Dissolution Tes~er ~odel AT6
supplied by So~x AG CH 4008 BASEL Switzerland. This
Apparatus comprises an array of polycarbonate beakers, each
capable of hold~g 1 litre of wa~er, supported in a thermostatically
controlled water ba~. Each beaker is provided with a padclle stirrer
whose xpeed can be controllled.
Two beakers in the Sotax Tester are employed in the perhydrolysis
procedure using the ~ollowing method:
1. Set water bath to re~uir~d te~perature ~20C).
2. Add 1 litre distilled water to each Sota~ beaker ~nd allow to
equilibrate ~o required ~e~perature.
3. Sample accurately 2 x l.Og samples of detergent and precursor.
4. Prepare a number of titratio~ beakers by adding:
25 ml 3:2 glacial acetic acid distilled water solution
together with 2 ice cubes
5. Set the stirfing speed of the SC)tZlX to 150 rpm.
6. Add ~he first sample to Sotax beaker No. 1 and start the clock
(t=C) ~utes). Add S ml potassium iodide solution to the
first titration beaker.
7. Take a 10 ml ~lig.uot from Sota~ beaker No. 1 and discharge
into the first titration beaker at t = 1 rniIlute.
8. Add the second sample to Sotax beaker No. 2- at t = 1 minute
a~d add S ml potassium iodide ~o a second titration beaker.
9. Titrate the first aliquot against 0.005 m sodium thiosulphate
svlution until the solution is first decolourised (The colour is
slowly regenerated as the solu~ion warms and the perhydratei
reacts wi~h the iodide).
10. Take a 10 ml aliquot from Sotax beaker No. 2 at t = 2
minutes and discharge into the seeond titration beaker and
r t t 9
epea s ep
11. Take further aliquots at the following times (t--minutes)
2 i ~
~VO 92/13798 PCI`/US~2~Q06M
37
~Ç~ÇL~ Beaker No. 2
(t) (t)
3 4
11 --
~ 21
Tlhe aliquots from Beakgr No. 1 at 1 miDute and ~om ~eaker Mo. 2
at 2 minutes constitute replicates and the results are aver~ged to give
a figure from which the ~o perhydrolysis is calcula~d.
Exa~nple 1
TAED in ~ e powder fonn (particle size 90% by weight ~150
micrometer~" was agglomerated with TAE25 to give particles in
which 85~; by weight was betwee~ D micrometers and 1700
micrometers. This material was divided into five ~actions identified
as A-F, of which fraction A was untreated a~d the remaiIlder were :-
treated as follows
Su~ce Treating Material
B 5% octanoic acid
C 5 % polyacrylic acid (MWt 2,000) ~:~
D 5% glycolic acid
:E~ S~a ci~ric acid
The treatments were all applied by ha~d spraying into a small coating ::
drum. The octaIIoic acid was applied as a melt at 60C whilst the
remainder were applied as aqueous solutions at ambient temperature
(20C). The citric acid solution was S0~ by weight, the glycolic
acid solution was 66% by weight and the polyacrylic acid solution
was 50% by weight.
2 1 ~
wo 92/13798 Pc~ Jss2/0
38
Material frvm each fraction was then inGorpora~ed into a model
detergent formulation h~ving the composition iIl parts by weight.
.
C 12LAS - 9.0 :
TAS 2.8
Dobanol 45E7 3.8
Zeolite A 23.5
Citrate 7.5
MA/AA 3.75
Carbo~ate 17.0
Silicate 4.2
(SiO2:~a2O=2:1~
DE~TPMP 0.4
CM(: 0 S
Percarbo~a~e 18.7
TAED . 5~85
Miscellaneous 3.00
The five formulations were then subjected to a Bealcer Perhydrolysis
Test as hereinbefore described and gave the perv~yacid yields shown
in Table 1 . Results are given for 1,3,5,10 lS & 20 minutes elapsed
time and are expressed in percent of the thevretically available
w~ight of per acid.
Table I
minutes ~om s~a~t of perhydrolysis
Product
withTAE:D fraction 1 3 5 10 15 20
A 37.3 74.2 86.0 93.9 97.8 97.2
B 23.2 60.1 75.9 90.8 97.4 96.5
~9.0 67.2 77.2 ~8.2 90.8 90.0
D 37.6 73.7 85.1 94.9 97.5 98.6
E 36.8 74.5 87.2 92.5 96.8 97.6
It can be seen that formulations containing ~e fractions D & E give
subst~ntially the same peroxyacid yield as that conta~ning fraction A,
(both after 3 minutes and throughout the perhydrolysis reaction),
WO 92/1379B 2101~ 4 8 PCI/IJS9~/00664
39
indicating that the perhydrolysis under uncons~ra~necl dissolution
coIlditio~s was substantially unaffected by the treatment . By
contrast formulatio~s containing ~ractions B & C ShQWed a lower
pero~y acid yield, particularly in the in~ial peri~ of the
perhydrolysis.
E~a~
The ~ormulations contai~g TAED fractions A ~ D of E~ample 1 ~;
were subjected to a filll scale washing machine test using Miele
au~omatic washing machines (Model W7543 set to the Short Wash
cycle at 40C. E~ach machirle was loaded with ~ur cotto~ bedsheets : `
(3.3 kg) and lOOg of the for~ulation was added go the fabrics iIl the ::
. machine drum via an Arielator (~TM) dispe~si~g device. 12 litres
of water of 150 ppm hard~ess (e~pressed as CaC033 with a Ca:M~
ratio of 3:1 was fed ~o each machi~e.
Two machines, adapted to allow openi~lg of the loading door during
the cycle for sampling purposes, were used to carry ou~ the same
procedure as employed in the Beaker Perhydrolysis Test . The
Results are shown in Table II and are expressed in the same manner
as for Table I
~able II
minutes from start of wash cycle
Prsduc~
wi~h TAED fraction 1 3 5 10 15 20
A 31.5 56.1 82.1 92.1 89.4 89.4 :
1~ 9. 1 50.6 68.~) 99.5 9~.5 96.7
It can be seen that, u~der the eo~strai~ed dissolutio~ conditions of a
loaded washing machi~e, the product contai~ g fracgion D (the
glycolic acid-sur~ace treated TAED), perhydrolyses more slowly
thaIl the product containing fractio~ A (the ulltreated material)9
duri~g the initial stages of the wash cyele. This shows that the
glycolic acid surface treatment of the TAE13 inhibits perhydrolysis
during the period of high localised product co~centration existing at
the star~ of the wash cycle, where the high aqueous solubility of the
acid is believed to create a low pH environment around the TAED
WO 92/1379X 2 i ~ 8 Pcr/~JS~2/00664
~o
particles. Nevertheless, in the later stages of the wash cycle, the
yield of peroxy acid from the treated TAED is Ibetter than from the
untreated material, indicating that delayed release of the TAED
results in its more effective conversion in~ pero~y aeid.
xam~ 3
A full scale washing machine test was ca~ried out compariIIg three
formulations co~ta~g fractions B, C & D of ~he surface treated
precursor of Example 1. The ~ractions were added respectively to a
modified form of the detergen~ ~or~ulatio~ of E~sample 1 irl vvhich
the sodium percarbonate was replaced by the same weight of sodium
perbora~e moIlohydrate.
The washing machi~e comparison employed the same technigue as
that used in Example 29 save that the wash tempçrature was 20C.
This temperature is typical of Ihat foun~d during the initial cold fill
stage of European wash cycles. Results are sh~wn below in Table
III
Table III
minutes fro~ start of wash cycle
iE;ormulation
with ~ac~ion 1 3 5 10 15 20
B 4.6 33.6 54.7 74.8 78.0 80.3
C: 4.6 32.6 54.3 80.7 84.8 8~.0
D 3.65 54.8 70.8 83.0 88.5 85.0
This shows that a peroxy acid bleach precursor sur~ace treated in
accordance with the inve~tion provides superior yields of pero~y
acid under realistic washi~g conditio~s, compared to sur~ace
trea~ment precursors that are not in accordance with the invention.
A washiIlg machine comparison of ~ormulations similar to tha~
carried out in Example III and incorporati~g precursor ~ractions
A,B, C & E was carried out to include bleach sensitive coloured
fabric swatches in the fabric load. These swatches were made of
2101fl~
WO 92/13798 PCl`/U~92/00664
41
100æ lambswool woven fabric with purple 48 dye (Design No.
W3970) supplied by Borval Fabrics, Albert Street, Huddersfield,
West Yorkshire, England. 24 replicates of each treatment were
performed and ~he swatches were then graded visually for fabric
colour damage by an expert panel USillg the ~ollowing grading ~:
system.
Three c~loured swatches demonstrati~g di~fenng degrees of eolour
damage are used as standards to establish a 4 point scale in which 1
represents 'virtually no damage' and 4 represen~s 'very damaged'.
The ~hree standards are used to define the mid points betweeIl the
various descriptions of colour damage viz
virb~ally no damage
2 slight damage
3 damage
4 verydamaged
Two expe~ parlellists are used and their results are averaged.
Using this technique to compare colour damage resulting from use of
~rmulatiolls contaLning precursor fractio~s A,B,C & E the following
results were ob~ained
% oif swatches having grade
formulation wi~h Overall
precursor ~raction 1 2 3 4 Grade
A S0 29.2 8.33 12.5 1.83
B 52.2 26.1 21.7 0 1.70
C 47.8 3~.4 17.4 4.4 1.7~
E 66.6 16.6 10.5 6.2 1.56
It can be seen that a formulation incorporating fraction E i~
accordance with the inverltion produces appreciably less ~abric
colour damage than noIl surface treated precursor or surface trea~ed
precursors not in accordance with the inven~iorl.
2 1 ~
WO 92/1379X PCl /U~i9~/00664
42
.
x~m~le V
The washing machine comparison of Example IV was repeated using
formulations containing TAED fractioIls A & D of Example 1, as
well as an additional TAED fraction ~ compnsing fraction A further
agglomerated with 10% by weight of glycolic aeid (on total
agglomerate weight basis). The formulatio~s were subjected to a
coloured swatch degradation test as described in E~ample IV and
gave the following results
% of swatches having grade Overall
2 3 4 Grade
A16 20 25 38 2.83
D29 38 29 4 2.08
9 35 35 22 2.70
It can be seen that fraction D, incorporatiIlg 5% glyeolic acid sur~ace
treated precursor particulates in accordance with the inventio~, has a
markedly lower overall damage grade than the untreated fraction A.
By contrast, the use of 10%, i.e. double the level, of glycolic acid as
an agglomerating agent results in little decrease in damage grade
relative to the Imtreated materi~l. This confirms the importance of
sur~ace treatment of the bleach precursor particulates in obtaining the
fabric damage reduction benefit of the inYentlon~
.,