Note: Descriptions are shown in the official language in which they were submitted.
~ 3.~ 31~ C 7073 (R)
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GRANULAR NON-PHOSPHORUS DETERGENT BLEACH COMPOSITIONS
This invention relates ~o granular non-phosphorus
bleach activator containing detergent bleach
compositions. Particularly it pertains to granular
compositions containing activators for peroxygen
bleaching agents in the form of organic peroxyacid
bleach precursor3 usable in phosphorus-free granular
detergent bleach compositions.
Granular detergent compositions which contain organic
bleach activators in addition to the usual detergent
substances having a cleaning action, builders and
peroxygen bleachinq agents are known in the art. The
peroxygen bleaching agents commonly used are those
which release hydrogen peroxide in aqueous solution,
such as alkali metal perborates, persilicates,
percarbonates, perphosphates and urea peroxide. These
peroxygen bleaching agents will hereinafter also be
referred to as "persalts". The most commonly u~ed
persalt in detergent compositions is alkali metal
perborate, particularly sodium perborate, tetrahydrate
or monohydrate.
The organic bleach activators referred to herein are
generally organic N-acyl or 0-acyl compounds, or
carbonic or pyrocarbonic esters, which react with
hydrogen peroxide (e.g. from the persalts) in solution
forming a peroxy acid or percarbonic acid, a bleaching
species which, unlike the persalts, i~ effective in
bleaching at lower temperatures, e.g. from ambient to
60C.
Such bleach activators are amply described in literature,
~or example in a serie~ o~ articles by Allan H. Gilbert
in Detergent Age, June 1967, pages 18-20, July 1967,
pages 30-33, and August 1967, page~ 26, 27 and 67, and
~ 3~ c 7073 (R)
further in Briti~h Patent Specifications 836,988,
855,735: 907,356; 907,358: 970,950; 1,003,310 and
1,246,339; US Patent Specification4 3,332,882,
3,277,750, 4,128,494 and 4,412,934.
A representative, but by no means comprehensive, list
of activators which can be u~ed in the present invention
is given below:
(a) ~-diacylated and N,N'-tetraacylated amine~, ~uch
as N,N,N',N'-tetraacetyl methylene diamine or ethylene
diamine, N,N'-diacetyl aniline and N,N'-diacetyl-p-
toluidine or 1,3-diacylated hydantoins as, for example,
the compound~ 1,3-diacetyl-5,5-dimethylhydantoin and
1,3-dipropionyl hydantoin:
(b) N-alkyl-N-suphonyl carbonamides, for example the
compounds N-methyl-N-mesyl acetamide, N-methyl-N-meqyl
benzamide, N-methyl-N-mesyl-p-nitrobenzamide, and N-
methyl-N-mesyl-p-methoxybenzamide:
(c) N-acylated cyclic hydrazides, acylated triazoles
or urazole4, for example monoacetyl maleic acid
hydrazide:
~ d) 0,N,N-trisubstituted hydroxylamines, such as 0-
benzoyl-~,N-succinyl hydroxylaminè, 0-acetyl-N,N-
~uccinyl hydroxylamine, 0-p-methyoxybenzoyl, N,N-
succinyl hydroxylamine, 0-p-nitrobenzoyl-N,N-succinyl
hydroxylamine and 0,N,N-triacetyl hydroxylamine:
(e) N,N'-diacyl sulphurylamides, for example N,N'-
dimethyl-N,N'-diacetyl 4ulphuryl amide and N,N'-diethyl-
N,N'-dipropionyl sulphurylamide;
(f) Triacyl cyanurates, for example triacetyl
cyanurate and tribenzoyl cyanurate:
~ 9) Carboxylic acid anhydrides, such as benzoic
anhydride, m-chlorobenzoic anhydride, phthalic
anhydride and 4-chlorophtalic anhydride,
(h) Sugar esters, ~or example glucose pentaacetate:
(i) 1,3-diacyl-4,5-diacyloxy-imidazolines, ~or
example l,3-diformyl-4,5-diacetoxy imidazoline, 1,3-
~ C 7073 (R)
diacetyl-4,5-diacetoxy imidazoline, 1,3-diacetyl-4,5-
dipropionyloxy imidazoline;
(j) Tetraacetyl glycoluril and tetraproprionyl
glycoluril;
(k) Diacylated 2,5-diXetopiperazines, such a~ 1,4-
diacetyl-2,5-diketopiperazine, 1,4-dipropionyl-2,5-
diketopiperazine and 1,4-dipropionyl-3,6-dimethyl-2,5-
diketopiperazine: -
(1) Acylation products of propylene diurea and 2,2-
dimethyl propylene diurea, especially the tetraacetylor tetrapropionyl propylene diurea and their dimethyl
derivatives;
(m) Carbonic acid esters, for example the sodium
3alts of p-(ethoxycarbonyloxy) benzonic acid and p-
(propoxycarbonyloxy) benzene sulphonic acid;
(n) Alpha-acyloxy-(N,N')polyacyl malonamides, such as
alpha-acetoxy-(N,N')-diacetyl malonamide.
Since these bleach activator compounds are generally
hydrolysable materials, they need to be protected from
the surrounding media when incorporated in detergent
compo~itions. On the other hand, any proper method of
protecting the bleach activator from the environment
must allow a relatively quick release or dissolution of
the activator in the wash liquor. Release of the
activator must be achieved at a period well before the
end of the wash cycle 30 as to give time for the
activator to react with the persalt forming the
peroxyacid. Preferably this should occur a~ early as
pos~ible in the wash cycle for maximum bleaching to
occur.
The moqt common way of protecting bleach activators i9
by presenting them in the form of granules or
agglomerates.
Various compo~itions and form~ of bleach activator
~ C 7073 (R)
granules have been proposed in the art, moqt of them
u~ing a phoqphate, particularly ~odium tripho~phate, a~
an essential component of the granulating agent because
of it~ typical property of imparting good structure
combined with quick disper~ion to the granule. A
representative example of ~uch bleach activator
granule compositions having good ~torage stability and
satisfactory release i~ that which comprise~ a mixture
of ~odium triphosphate and pota~sium tripho~phate a~
the granulating agent, currently used in the majority
of commercial detergent powder formulations~
For many years, pho~phates, such a~ ~odium triphosphate,
have indeed been used as detergency builders.
With the increaqing trend of legislation in a number of
countries to ban phosphorus from detergent compositions,
because of the general belief that phosphates and
phosphorus-containing compounds can lead to
environmental problems, it has become desirable and
necessary to provide detergent compositions which are
free, or es~entially free, of phosphoru~.
Consequently, in formulating such phosphorus-~ree
detergent bleach compositions comprising a bleach
activator, it has also become nece~sary to look for a
rea~onable alternative to bleach activator granule
compositions which are free o~ phr,~phorus but which
should have the phy~ical properties and performance
characteristics comparable to phosphoru~-containing
bleach activator granules when used in detergent
compositions under non-phosphorus conditions.
A number of alternative non-phosphorus builders have
been proposed, especially a mixture o~ an alkali metal
carbonate, such as sodium carbonate, with a water-
in~oluble calcium carbonate ~eed material, such as
~ 831~ C 7073 (R)
calcite, a~ disclosed for example in GB Patent
Specifications 1,437,950 (Unilever), 1,481,516
(Vnilever) and 1,481,685 (Unilever), and it iq for use
in compositions containing such builderq that the
present non-phosphorus bleach activator granule
composition i~ particularly de~igned.
Non-phosphorus-containing bleach activator granule
composition~ are known in the art and various method3
of preparing such granuleQ and their use in detergent
compositions have been proposed.
In the majority of ca~es an organic compound or a
mixture of organic compounds were proposed as the
binding or coating agent, such as for example nonionic
compounds, fatty acids, fatty alcohols, waxeq and
polymeric materials with or without the optional u~e of
inorganic salts.
German DE-OS 2,657,042 discloses a detergent composition
compri~ing tetraacetyl ethylene diamine (TAED) in the
form of granules, which consist of said TAED activator
and a nonionic surfactant having a melting point of at
least 35C as the binding agent.
European EP-B-0051987 (Procter & Gamble) discloses
bleach activator granule compositions comprising a
bleach activator and a nonionic surfactant having a
melting point of not more than 40C a~ binding agent.
A major disadvantage of nonionic~ is that they tend to
bleed and cause ~tickine~s, giving rise to caking
problem~, e~pecially under hot ~ummer temperature
conditions. Migration of nonionics in the formulation
would also tend to aid decomposition of bleach-
sensitive ingredients owing to interaction with the
oxidising bleach ~ystem. Higher melting nonionicq will
~ .2~3~ C 7073 (R)
have poor disper~ing ability, resulting in a poor
release of the bleach activator, with the deleterious
consequence of the granules sedimenting and being 108t
in the dead spaces of the washing machine~, known as
mechanical lo~s. The ~ame applieq to fatty acids, fatty
alcohols and waxe~.
European Patent Specification EP-0070474 and EP-0037026
~Henkel) disclose methods of using water-soluble
cellulo~e ether, starch or Ytarch ether a~ granulation
binder for preparing bleach activator granules having a
bleach activator content of from 90-99~ by weight. The
method~ as described here are only viable if coarse
particle size bleach activatorq are used.
European Patent Application EP-0075818 (BASF) di~clo~es
water-free activator granules comprising a) 70-9~.5
bleach activator and b) 0.5-30~ of a swelling agent,
prepared by compacting the compounds a) and b) without
the addition of water, optionally followed by breaking
into smaller particles.
As swelling agents are mentioned high molecular weight
carbohydrates, such as starch, powdered cellulose, wood
pulp; cro~-linked polyvinyl pyrrolidone (PVP) and also
ætarch ether and carboxymethyl cellulose.
All the~e proposal~ have been made without the object
of using such bleach activator granules in non-
pho~phorus detergent formulations, especially indetergent compositions containing an alkali metal
carbonate and calcium carbonate seed material as the
builder system.
Accordingly, it i8 an object of the present invention
to provide an effective and ~table granular non-
phosphorus-containing bleach activator composition
~ 311 C 7073 (R)
which can be used in non-phosphoru~ granular detergent
bleach compositions containing as builders a mixture of
an alkali metal carbonate with a water-insoluble
particulate carbonate material, which ic capable of
acting a~ a seed crystal for the precipitate resulting
from the reaction between the calcium hardne~ ions of
the water and the water-~oluble carbonate, e.g. a
mixture of sodium carbonate and calcite without
poisoning the water-insoluble carbonate material,
e~pecially calcite, whereby its seed activity iB
reduced.
This a~d other objects, which will be apparent from
the further de~cription of the invention, can be
achieved if a finely divided particulate bleach
activator i3 granulated to a 3ize of from about 0.2-2.0
mm, using an inert non-alkaline, non-phosphate
inorganic or organic salt and a water-soluble, low- to
non-carboxylate containing film-forming polymeri`c
material having average molecular weiyht o ~rom 500-
l,000,000, as granulating agent.
It is known that calcite 19 ~en~itive to poisoning,
which will re~ult in a marked detrimental effect on
calcite precipitation. In this respect the type of
polymeric material used in the invention is crucial.
Thus the granular bleach activator composition of the
invention is es~entially free of phosphoru~ m~terial~
, /
.
3 ~r~ C 7073 ~R)
and comprises:
(i) a finely divided particulate bleach activator;
(ii) an inert non-alkaline, non-phosphate, water-
soluble inorganic or organic salt; and
(iii) a water-soluble, low- to non-carboxylate
containing film-forming polymeric material of
average ~olecular weight of from 500-1,000,000.
Preferred bleach activators are the N-diacylated and
N,N'-tetraacylated amines mentioned under a) above,
particularly N,N,N',N'-tetraacetyl ethylene diamine,
the esters of carbonic or pyrocarbonic acids mentioned
under m~ and the reactive phenol esters as described in
US Patent Specification 4,412,934 and Ga Patent
Specifications 836,988 and 864,798.
The inert non-alkaline, non-phosphate inorganic or
organic salts ~hich can be u~ed in the invention are,
for example, sodium sulphate, sodium nitrate, sodium
chloride, sodium citrate, calcium sulphate and calcium
chloride. A preferred salt i5 sodiu~ sulphate.
The low- to non-carboxylate film-forming polymeric
material usable in the invention will be any polymer,
both homo- and co-polymers, which have a carboxyl group
to polymer weight ratio of le~q than 1:5. They may be
composed of monomer3 ~uch as vinyl acetate, vinyl
pyrrolidone, methyl vinylether, styrene and styrene
sulphonate, alkyl acrylates, etc. Examples of suitable
polymeric materials include polyvinylpyrrolidone,
polyvinyl alcohol, co-polymers of polyvinyl alcohol/
polyvinyl acetate, carbohydrates and carbohydrate
ether~ such as carboxymethyl cellulose, and dextrin~
modified vinylacetate polymers. Polymers having average
molecular weight of le3s than 500,000, particularly
less than 100,000, are pre~erred.
Other polymeric ~aterial~ out~ide those as defined in
the present invention are not suitable as they tend to
cause serious poisoning of calcite.
Effectively, the granular bleach activator composition
~ill compri~e:
ta) from 50-90%, preferably from 55-85% by weight, of
the bleach activator;
(b) fro~ 5-45~, preferably from 10-35% by weiqht, of
the inorganic or organic salt; and
(c) from 1-15~, pre~erably from 5-10~ by ~eight, of
of the low- to non-carboxylate
polymeric material.
Water may be present in an amount of up to about 5%,
preferably up to 4%.
r
As explained hereinbefore, the granular bleach
2~ activator composition has particular applicability to
non-phosphorus detergent composition~ containing as
builders a mixture of an alkali metal carbonate, such
as sodium carbonate, with a ~ater-insoluble carbonate
seed material, 3uch as calcium caebonate, e.g. calcite.
Accordingly, the invèntion provides a granular
detergent bleach composition which is substantially free of
phosphorus-containing material, comprising:
(i) a detergent active material;
(ii) a water-soluble carbonate material which
is a detergency builder;
(iii) a water-insolubl.e particula-te carbonate
material which is a seed crystal for
calcium carbonate;
1.~.
9a
(iv) a peroxygen bleaching agent; and
(v) a bleach activator, characterized in that
the bleach activa-tor is present in the
form of non-phosphorus granules of a size
from 0.2 to 2.0 mm comprising:
(a) from 50-90% by weight of a finely
divided particulate bleach activator
(b) from 5-45~ by weight of an inert
non-alkaline, non~phosphate, water-
soluble inorganic or organic salt;
and
(c) from 1-15~ by weight of a
water-soluble, low- to non-
carboxylate containing film-forming
polymeric material having a carboxyl
group to polymer weight ratio of less
than 1:5, of average molecular weight
from 500-1,000,000.
.
//
PVp~, ~
C 7073 (R)
The detergent-active material can be anionic, nonionic,
cationic or zwitterionic or a mixture of such agents.
Nonionic ~urfactants suitable for use in the present
invention include water-soluble sompounds produced by
the condensation of ethylene oxide with a hydrophobic
compound such as an alcohol, alkyl phenol, polypropoxy
glycol or polypropoxy ethylene diamine. Al~o ~uitable
are alkyl amine oxides, alkyl polyglucosides and alkyl
methylsulphoxides. Preferred nonionic suractants are
polyethoxy alcohols formed as the condensation products
of 1 to 30 moleY of ethylene oxide with 1 mole of
ethylene oxide with 1 mole of branched- or straight-
chain, primary or secondary aliphatic alcohol~ having
from about 8 to about 22 carbon atoms, more especially,
6 to 15 Moles of ethylene oxide are condensed with 1
mole of straight- or branched-chain, primary or
secondary aliphatic alcohol having from about 10 to
about 16 carbon atoms. Certain polyethoxy alcghols are
A 20 ~ ommercially ava ~ able under the trade-names7~'Neodol",
"Synperonic" and 'Tergitol".
Anionic surfactants suitable for use in ~ormulating the
detergent bleach compo~itions o~ the invention include
water-soluble alkali metal alkylbenzenesulphonates,
alkyl ~ulphates, alkylpolyethoxyether sulphates,
paraffin sulphonates, alpha-olefin sulphonates, alpha-
sulphocarboxylates and their e~ters, alkylglycerylether
sulphonates, fatty acid monoglyceride sulphates and
sulphonates, alkylphenolpolyethoxy ethersulphates,
2-acyloxyalkane-1-sulphonates and beta-alkyloxyalkane
sulphonates. Soap~ can also be u~ed as anionic
surfactants. Preferred anionic surfactants are
alkylbenzene~ulphonates with about 9 to about 15 carbon
atoms in a linear or branched alkyl chain, more
especially about 11 to about 13 carbon atoms;
alkylsulphaSes with about 8 to about 22 carbon atoms in
~8 tra~ k
~.2~3~
7073 (R)
the alkyl chain, more especially from about 12 to about
18 carbon atom~; alkylpolyethoxy ethersulphates with
about 10 to about 18 carbon atoms in the alkyl chain
and an average of about 1 to about 12 -CH2CH20-
groups per molecule; linear paraffin sulphonate~ withabout 8 to about 24 carbon atoms, more especially from
about 14 to about 18 carbon atoms and alpha-olefin
sulphonate~ with about 10 to about 24 carbon atoms,
more especially about 14 to about 16 carbon atoms; and
soaps having from 8 to 24, especially 1~ to 18 carbon
atoms.
Cationic surface-active agents suitable for use in the
invention include the quaternary ammonium compounds,
e.g. cetyltrimethylammonium bromide or chloride and
distearyldimethylammonium bromide or chloride, and the
fatty alkyl amines.
Zwitterionic surfactants that can be used in the
present invention include water-soluble derivatives of
aliphatic quaternary ammonium, phosphonium and
sulphonium cationic compounds in which the aliphatic
moieties can be ~traight or branched, and wherein one
of the aliphatic sub~tituents contains from about 8 to
18 carbon atoms and one contain~ an anionic water-
solubilizing group, especially alkyldimethylammonium
propanesulphonates and carboxylates tbetaines) and
alkyldimethylammoniohydroxy propane~ulphonates and
carboxylates wherein the alkyl group in both types
contain~ from about 8 to 18 carbon atoms.
Typical listings of the clasRes and ~pecies of
surfactants useful in this invention appear in "Surface
Active Agents", Vol. I, by Schwartz & Perry
~Interscience 1949) and "Surface Active Agents", Vol.
II, by Schwartz, Perry & Berch (Interscience 1958~.
C 7073 ~R)
The preferred detergent active compounds are fully
described in Gs 1,437,950 referred to above.
The effective amount of the detergent active compound
or compounds used in the c'omposition is generally in
the range from 5 to 40% by weight, preferably not more
than 30% by weight of the composition.
A second es~ential ingredient of the composition is a
water-soluble carbonate material as a buildex. This is
preferably sodium or potassium carbonate or a mixture
thereof, for reasons of cost and efficiency. The
carbonate salt is preferably fully neutralised but it
may be partially neutrali~ed, for example a
sesquicarbonate may be used in partial replacement of
the normal carbonate salt; the partial salts tend to be
less alkaline and therefore less efficient. The amount
of water-soluble carbonate material in the detergent
composition can be varied widely, but the amount should
be at least 5% by weight, such as from 10% to 40~,
preferably 10% to 30~ by weight, though an amount of up
to 75% could possibly be used, if desired, in special
product~. The amount of the water-soluble carbonate
material is determined on an anhydrous ba~is, though
the ~alts may be hydrated either before or when
incorporated in the detergent composition. It should be
mentioned that within the preferred range the higher
level~ tend to be required under conditions of use at
low product concentration3, as i8 commonly the practice
in North America, and the conver~e applies under
conditions of use at higher product concentrations, as
tends to occur in Europe. It should be noted that it
may also be desirable to limit the carbonate content to
a lowex level within the range mentioned, 80 as to
decrease the risk of internal damage following any
accidental inge~tion, for example by children.
--~ C 7073 ~)
13
In addition to the water-soluble carbonate material it
i5 possible to include minor amounts of other non-
phosphorus detergency builders, provided that the total
amount of the detergency builders does not exceed 85%
by weight, so as to leave room in the detergent
composition for other desirable ingredients.
Where a soap is used as a detergent active material, it
may be present in such a quantity that it will also
contribute as an additional builder.
The composition further nece~sarily contains a ~ater-
insoluble particulate carbonate material. This material
must be capable of acting as a seed crystal for the
precipitate which results from the reaction between the
calcium hardness ionS of the water and the water-soluble
carbonate. Thus this water-inQoluble particulate
material is a seed cry~tal for calcium carbonate, such
as calcium carbonate itself.
The water insoluble particulate carbonate material
should be finely divided and should have a surface area
of at least 10 m2/g, and preferably at least 15 m2/g.
The particularly preferred material has a surface area
from 30-100 m2/g. Insoluble carbonate material with
surface areas in exce~s of 100 m2/g may be used if
such materials are economically available.
Surface area i9 measured by nitrogen absorption using
the standard Bruauer, Emmet & Teller (BET) method. A
Quitable machine for carrying out this method i9 a
Carlo Erba Sorpty 1750 instrument operated according to
the manufacturer 1 8 instructions.
It is most preferred that the high surface area material
be prepared in the absence of poisons, ~o as to retain
itq ~eed activity.
C 7073 (R)
14
The insoluble carbonate material will usually have an
average particle size of le58 than 10 microns, as
measured by sieve analy3is.
When the i~soluble carbonate material i~ calcium
carbonate, any crystalline form thereof may be u~ed or
a mixture thereof, but calcite i~ preferred as aragonite
and vaterite are less readily available commercially,
and calcite is a little less soluble than aragonite or
vaterite at most usual wash temperatures. When any
aragonite or vaterite is used, it i3 generally in
admixture with calcite. In the following general
de~cription, the term 'calcite' i~ used to mean either
calcite itself or any other ~uitable water-insoluble
calcium carbonate seed material.
The selected level of calcite in the overall composition
depends on the specific surface area a~ described
above. The amount of calcite u~ed in the composition~
should be from 5~ to 60%, more preferably from 5% to
30%.
The amount of peroxygen bleaching agent u~ed in the
composition~ of the invention will generally be from 5
to 30% by weight, preferably from 7% to 25~ by weight.
¦ The amount of non-pho~phoru~ bleach activator granule~
incorporated in the compositions will depend on the
bleach activator content of the granule composition
and may be from 0.5~ to 15~ by weight, more preferably
from 1.5% to 10~ by weight, calculated a~ pure bleach
activator.
With re~ard to the bleach activator as u~ed in preparing
the granular bleach activator composition~, it is
pre~erred that it~ particle size should be less than
200 micrometre, more preferably up to 150 micrometre.
",~i,,~
~ ~3~3~311 C 7073 (R)
. _
Suitable bleach activators are tho~e having a major
proportion of particle ~ize of between 50 micrometre
and 150 micrometre. Particle size di~tribution a9
described in US Patent Specification 4,283,302 are
especially suitable.
The detergent compo~ltion~ in whlch the granular non-
phosphoru~ bleach activator compositions are incor-
porated can optionally contain any of the conventional
ingredients in the amountq in which such ingredients
are normally employed in fabric washing detergent com-
positions.
One ~uch optional ingredient i8 an alkali metal
silicate, particularly sodium, neutral, alkaline, meta-
or ortho~ilicate. A low level of ~ilicate, for example
from about 2-10~ by weight, i9 usually advantageous in
decreasing the corrosion of metal parts in fabric
wa~hing machines and it may give processing benefits.
If higher levels of silicate are used up to a practical
maximum of 30%, for example from 10~ to 20~ by weight,
there can be a more noticeable improvement in detergency,
which may permit some decrea~e in the water-soluble
carbonate material content. ~his effect appears to be
particularly beneficial when thé wash liquor i~ used in
water with appreciable levels of magnesium hardne~.
The amount of ~ilicate can also be used to some extent
to control the equilibrium pH of the wash liquor, which
i~ generally within the range of 9-11, preferably 10-
11, for an aqueou~ ~olution of the composition at therecommended concentration. It should be noted that a
higher pH ~i.e. over pH 10.5) tends to be more
efflcient as regards detergency, but it may be less
desirable for domestic qafety. Sodium ~ilicate i8
commonly ~upplied in concentrated aqueous solution or
in concentrated powder ~orm, but the amountq are
calculated on an anhydrous basis.
C 7073 (R)
16
Example~ of other optional ingredients include the
lather boo~ter~, such a~ alkanolamide~, particularly
the monoethanolamide~ derived from palmkernel fatty
acidq and coconut fatty acid~, lather depre~sants,
fabric ~oftening agent~, inorganic ~alt~, such a~
sodium ~ulphate, and, u~ually present in very minor
amount~, fluorescent agents, perfume~, enzymes, such a~
protea~e~ and amyla~e~, germicide~ and colourants.
Particularly when the composition doe~ not contain an
anionic detergent active material, it can be beneficial
to include an anti-ashing material to reduce the
depo~ition of calcium carbonate on to fabric~.
The detergent composition~ may be produced by any of
the technique~ commonly employed in the ~anufacture of
fabric wa~hing detergent compositions, including
particularly slurry-making and spray-drying proce~se~
for the manufacture of detergent powders.
The invention will now be further illu~trated by
reference to the following non-limiting Exa ples
~ .
~r
? ~ C 7073 (R)
17
Example I
The following granular non-phosphorus bleach activator
composition wa~ prepared:
Composition I ~_by weight
TAED (bleach activator) ~3.8
Sodium sulphate 9.4
Vinylacetate polymer 3.1
10 Water 3-7
A solid feed conqiqtin~ of a mixture of 90% TAED
(average particle ~ize of 50-150 micrometre) and 10%
sodium ~ulphate was sprayed in a Schugi~ Flexomix 160
apparatu~ with the proper amount of an aqueous solution
consi~ting of 15~ polymer and 85~ water. The product wa~
aerated to dry and obtain a product of the above
compo~ition with the following properties:
Comp. IControl Comp. A
Bulk density g/l 418 500-640
Dynamic flow rate mlts 120 80
Compre~ibility ~ 8.2 20
Granulometry:
Mean particle size micrometre 619 600~800
% ~1700 micrometre nil
~< 250 micrometre 5.2 5
% < 125 micrometre 1.2 2
30 Control ~ranule Comp. A ~ by weight
TAED (bleach activator) 58-62
Sodium triphosphate 18-22
Pota~sium triphosphate 13-15
Water 5~7
~ ~83~1 C 7073 ~R)
.,
Example II
The follow.ing granular non-phosphorus bleach activator
(TAED) composition was prepared:
Composition of Granule II ~ by _eight
TAED 67.8
Sodium sulphate 22.6
Vinyl Dextrin polymer 5.6
10 Water 4.0
A solid feed consisting of a mixture of 75~ TAED
(average particle size of 50-150 micrometre) and 25~
sodium sulphate ~as sprayed in a Schugi~ Flexomix 160
apparatus with the proper amount of an aqueous solution
of polymer. The product was dried in a fluid bed to
yield a product of the above compo~ition with the
following propertieR:
Composition II
sulk density (9/1) 4~0
~ynamic flow rate (ml/s) 89
Compressibility (~) 9
Gran~lometry:
Mean particle size (micrometre) 748
% ~1700 micrometrenil
% < 250 micrometre1.0
~ ~ 125 micrometre0.1
TAED Delivery
Composition II
Peracid yield, peak value m mol/l 1.18
Peracid yield, peak time minuteq 15
Storage Resultq
Storaqe properties o~ these granules in a calcite/
. ~.
. . .
~ 3~ ~ C 7073 (R)
-
19
carbonate base powder containing odium perborate
monohydrate stored in non-laminated carton~ at
37C/70% RH:
Composition II
TAED decomposition %
after 2 week~ 40.4
after 4 weeks 59.6
Perborate decomposition ~
after 2 weeks 10.2
after 4 weeks 19.4
Poisoning of Calcite
A test procedure wa~ adopted whereby to a solution
containing 20H Ca (as CaC12) was added 1.5 g/l
sodium carbonate and 0.5 g/l calcite (Socal U3) in the
presence of 10 ppm STP to simulate poi~ons occurring in
a practical wash liquor. The effect of TAED granules at
0.15 g/l (100% basis) was noted. The experiment was
carried out at 25C u~ing Na2S04 to bring the ionic
strength of the medium to 0.1.
H Ca at 15 minute~
(i) No TAED granule 0.31
(ii~ Granule II 0.35
(iii) Control granule A 1.96
It can be ~een that the granule made according to the
invention haq no effect on water softening, wherea~ a
granule containing a poison cau~e~ a drastic reduction
in the water ~oftening achieved.
.~
31~
C 7073 (R)
Washin~ Machine Performance
Calcite/carbonate + Granule II vs. Commercially
=
available Phosphate Powder and Control Granule A
rThe commercially available phoqphate powder u~ed wa~
German Omo base powder.]
Calcite/carbonate powder composition % by wei_ht
10 Sodium C12-alkyl benzene sulphonate 7.7
Nonionic ethoxyla~e 3.4
Sodium stearate 3.4
Sodium carbonate 30.0
Calcite 20.2
15 Sodium silicate 6.0
Enzyme 0-5
Sodium perborate monohydrate5.5
TAED (100~ basis) 2.3
Sodium sulphate/SCMC/water to 100
The two compoqitions were used to wash 2.5 kg of a
soiled fabric load in washing machines having a
capacity of 18 litres, the load including a number of
bleach-sensitive test clo~hs. ~he reflectance of these
cloths was mea~ured both before and after the wash and
the difference (aR460*) calculated. The wash
condition~ were a pre-wash followed by a 35 minute wash
cycle heating up from 15C to 60C. The water hardne~s
was 40FH ~Ca:Mg molar ratio 4:1). 80 g each
composition was used in the pre-wash, 100 g for the
main wash. The pH of the wash liquor was mea~ured both
be~ore and after the wash. The results were as follows,
being averaged over 6 washes:
~ 3~ C 7073 (R)
21
Calcite/Carbonate Phosphate
+ Granule II + Control A
Initial pH10.6 10.1
Einal pH 10.4 9.4
5 ~R460* 17.8 13.0
Example III
Similar good results were obtained with the following
granular non-phoæphoru~ bleach activator ~TAED)
compo~ition:
Composition (~ by weight? II
TAED 83.4
Sodium sulphate 8.6
Vinyl acetate homopolymer 8.0
Water
20 The granular bleach activator granules were used in
carbonate/calcite base powder compo~itionæ. No poisoning
of calcite was ob~erved.
