Note: Descriptions are shown in the official language in which they were submitted.
CA 02289305 1999-11-10
1
Detergent Shaped Body with Enhanced Dissolving Properties
Field of the Invention
This invention relates generally to compact shaped bodies having
detersive properties. More particularly, the invention relates to detergent
shaped bodies such as, for example, detergent tablets, dishwasher tablets,
stain remover tablets or water softening tablets for use in the home, more
particularly for use in machines.
Background of the Invention
Detergent shaped bodies are widely described in the prior-art
literature and are enjoying increasing popularity among consumers
because they are easy to dose. Tabletted detergents have a number of
advantages over powder-form detergents: they are easier to dose and
handle and, by virtue of their compact structure, have advantages in regard
to storage and transportation. As a result, detergent shaped bodies are
also comprehensively described in the patent literature. One problem
which repeatedly arises in the use of detergent shaped bodies is the
inadequate disintegrating and dissolving rate of the shaped bodies under
in-use conditions. Since sufficiently stable, i.e. dimensionally stable and
fracture-resistant, shapedl bodies can only be produced by applying
relatively high pressures, the ingredients of the shaped body are heavily
compacted so that: disintegration of the shaped body in the wash liquor is
delayed which results in excessively slow release of the active substances
in the washing pro~;,ess.
The problem of tlhe overly long disintegration times of highly
compacted shaped bodies is known in particular from the pharmaceutical
industry where certain disintegration aids, so-called tablet disintegrators,
have been used for some time in order to shorten the disintegration times.
According to Roimpp (9th Edition, Vol. 6, page 4440) and Voight
"Lehrbuch der ~rharmazeutischen Technologie" (6th Edition, 1987,
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pages 182-184), tablet disintegrators or disintegration accelerators are
auxiliaries which provide for the rapid disintegration of tablets in water or
gastric juices and' for the release of the pharmaceutical principles in an
absorbable form.
"Hagers Handbuch der pharmazeutischen Praxis" (5th Edition,
1991, page 942) classifies the disintegration accelerators or disintegrators
according to their action mechanism, the most important action mechan-
isms being the swelling mechanism, the deformation mechanism, the
wicking mechanism, the repulsion mechanism and the evolution of gas
bubbles on contact with water (effervescent tablets). In the case of the
swelling mechanism, the particles swell on contact with water and undergo
an increase in volume. This produces local stresses which spread
throughout the tablet and thus lead to disintegration of the compacted
structure. The deformation mechanism differs from the swelling
mechanism in the fact that the swelling particles were previously
compressed during the tabletting process and now return to their original
size on contact wiith water'. In the case of the wicking mechanism, water is
drawn into the intE~rior of the shaped body by the disintegration accelerator
and loosens the binding forces between the particles which also results in
disintegration of the shaped body. The repulsion mechanism differs
additionally in the fact that the particles released by the water drawn into
the pores repel ~~ne another under the effect of the electrical forces
generated. A totally different mechanism forms the basis of "effervescent
tablets" which contain active substances or active-substance systems
which, on contact with water, release gases that cause the shaped body to
burst. In addition, it is known to use hydrophilicizing agents which provide
for better wetting of the compressed particles in water and hence for faster
disintegration.
Whereas substances which act by the last two of the above-
mentioned mechanisms can easily be distinguished from other
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disintegration me~chanisrns, the effects on which the swelling and
deformation mechanisms and the wicking and repulsion mechanisms are
based cannot always be clearly distinguished from one another, so that
classification into hydrophilicizing agents, gas-releasing systems and
swelling disintegrators is nnore appropriate for practical reasons.
The use of these various disintegrators either on their own or in
combination with oneanother is well known from pharmaceutical
applications. Thus, EP-k3-0 396 335 (Beecham Group PLC) discloses
chewing tablets which, in addition to 1 to 30% by weight of an effervescent
system of 0.5 to 20% by weight of citric, tartaric, adipic, fumaric or malefic
acid and 0.5 to 30% by weight of Na, K or Ca (hydrogen) carbonate or Na
glycine carbonate, also contain 5 to 30% by weight of a disintegrating
agent, such as (modified) cellulose, polyvinyl pyrrolidone or starch
glycolate. According to the document in question, the advantage of these
chewing tablets liens in a more pleasant application for the patient and in a
more pleasant feeling during ingestion.
Combinations of effervescent granules and swelling disintegrators
are also known from JP 06 024 959 (BAYER YAKUHIN KK, Derwent
Abstract). This document describes pharmaceutical compositions in tablet
form, the active principles being mixed with a disintegrator (methyl
cellulose, carboxymethyl cellulose, polyvinyl alcohol, polyvinyl pyrrolidone)
and partly coated with disintegrators containing a swelling gel-forming
polymer (sodium alginate, carrageenan, polyethylene oxide) and a C02-
generating effervescent system. Despite the use of two disintegration
systems, these tablets arE~ claimed to be delayed-release active-principle
carriers.
The proposed solutions mentioned above produce the required
result in the tabletting of pharmaceutical products. Although, in the field of
detergents, they contribute; towards improving the disintegration properties
of detergent tablets, the improvement achieved is inadequate in many
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cases. This applies in particular when the percentage content of tacky
organic substances in the tablets, for example anionic and/or nonionic
surfactants, increases. In addition, the use of the disintegration aids in
detergent tablets c;an lead to specific problems which are entirely unknown
in the case of pharmaceutical products.
For example, the use of an effervescent system in detergent tablets
does not produce the rapid disintegration required, instead the effervescing
and disintegrating effect known from conventional effervescent tablets does
occur to begin with, but stops after only a short time so that, thereafter,
the
tablet does not undergo any further disintegration. It would appear that a
water-impermeable layer is formed after a short time from the detergent
ingredients mentioned, thus preventing the water from entering the tablet
and, hence, the tablet from disintegrating.
Accordingly, European patent application EP-A-0 466 484 (Uni
lever), for examplE~, describes tablets of compacted particulate detergent
which, besides :~urfactant(s) and builder(s), optionally contain other
detergent ingredients, including binders/disintegrators among which
swelling types are preferred.
Effervescent detergent tablets are described in DE 35 35 516
(Bucher). These i:ablets contain 2 to 6% by weight of a surfactant, 40 to
60% by weight of hydrogen carbonate, 33 to 53% by weight of a solid
organic acid (more particularly a 2:3 mixture of citric and tartaric acid),
1.5
to 2.5% by weight of polyvinyl pyrrolidone and, in addition, colloidal silicon
dioxide. However, thesE~ tablets are not laundry detergents, but are
preferably used in the screen washer system of motor vehicles and for floor
care.
Where conventional swelling disintegrators, such as starch and
cellulose or derivatives thereof and polymers, such as polyvinyl pyrrolidone
or polyvinyl alcohol, are used in laundry detergents, the tablets obtained
disintegrate more or less quickly in water. However, disintegrators of the
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type mentioned cause residue problems on the treated laundry when used
in the quantities required for rapid disintegration.
Summary of the Invention
Accordingly, the problem addressed by the present invention was to
5 provide effervescent detergent shaped bodies which, on the one hand,
would disintegrate rapidly in the wash liquor but which, on the other hand,
would not leave any residues on fabrics.
It has now been found that the disintegration problems of an
effervescent detergent shaped body can be overcome by introducing a
swellable water-in.~oluble .disintegration aid - in addition to the
effervescent
system - into the shaped body.
In a first ernbodimE~nt, therefore, the present invention relates to a
detergent shaped body of compacted particulate detergent containing
surfactant(s), builders and optionally other detergent ingredients, the
shaped body additionally containing
a) to 10% byy weight of one or more swellable water-insoluble
disintegration aids and
b) 3 to 60% by weight of a gas-generating effervescent system.
More particularly, the present invention provides a shaped detergent
body of compacted particulate detergent comprising:
a) 1 to 10 percent by weight of one or more swellable, water-insoluble
disintegration aids selected from the group consisting of polyvinyl
pyrrolidone, polyvinyl alcohol, and natural and chemically modified
biopolymer~;;
b) 3 to 60 percent by weight of a gas-generating effervescent system;
c) at least one ;~urfacta~nt; and
d) at least one builder.
In another aspect, the invention provides a process for the
production of shaped detergent bodies comprising compressing a
particulate detergent comprising:
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a) 1 to 10 percent by weight of one or more swellable, water-insoluble
disintegration aids selected from the group consisting of polyvinyl
pyrrolidone, polyvinyl alcohol, and natural and chemically modified
biopolymer.~;
b) 3 to 60 percent by weight of a gas-generating effervescent system;
c) at least one surfactant; and
d) at least one builder.
In the context of the present invention, the contents of a) and b) in
the detergent are hereinafter referred to in short as "component a)" and
"component b)". The term "component" in this context is purely a linguistic
construction. More particularly, the effervescent system b) may consist of
several chemical compounds which do not have to be present in the form
of a single compound. O~n the contrary, the total content of the chemical
compounds in question, which may also be present in totally different
individual raw materials or compounds, is calculated and referred to as
"component b)". :>imilarly, the swellable water-insoluble disintegration aids
do not have to be present in the form of a single compound. In their case,
too, several disintegration aids of the type mentioned may optionally be
present in the various individual raw materials and/or compounds which are
calculated together as "component a)".
Detailed Description of the Invention
The swellalble water-insoluble disintegration aids {component a)}
used include, above all, polymeric substances having molecular weights of
a few ten thousand to a few hundred thousand gmol-'. Besides synthetic
polymers such as, for example, polyvinyl pyrrolidone and polyvinyl alcohol,
natural and chemically modified biopolymers selected, for example, from
the group of alginates, starches and cellulose are particularly suitable for
use as component a). Component a) is preferably selected from natural
and synthetic polysaccharides and derivatives thereof.
These groups include, for example, the pure polysaccharides, starch
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and cellulose, bui: also esterification and etherification products in which
hydroxy hydrogen atoms have been substituted. However, celluloses and
starches in which the hy~droxy groups have been replaced by functional
groups not attached via an oxygen atom may also be used as
polysaccharide derivative:.. The group of cellulose derivatives includes, for
example, alkali mE~tal celluloses, carboxymethyl cellulose (CMC), cellulose
esters and ethers .and aminocelluloses while the group of starch derivatives
includes, for example, carboxymethyl starch (CMS).
Microcrystalline cellulose may of course also be used as a swellable
water-soluble disintegration aid. This cellulose has primary particle sizes of
ca. 5 Nm and can be compacted, for example, to granules with an average
particle size of 200 Nm. The resulting compactates are stable and can be
mixed with other' substances without disintegrating into the primary
particles.
Not only can the swellable water-soluble disintegration aids be used
in the form of fine-particle powders, they can also be converted into coarser
particles by spray drying, granulation, agglomeration, compacting, pelleting
or extrusion. These "granulated" disintegration aids include not only
granular disintegrators, Ibut also, for example, disintegrators in co-
granulated or otheirwise compacted form.
In preferred detergent shaped bodies, 1 to 10% by weight, prefer-
ably 2 to 7% by weight and more preferably 3 to 5% by weight, based on
the shaped body as a whole, of a cellulose or cellulose derivative is used
as component a).
The gas-gE~nerating effervescent system {component b)} may
consist of a single substance which releases a gas on contact with water.
Among these compounds, the magnesium peroxide already referred to in
the foregoing, which releases oxygen on contact with water, is mentioned
in particular. However, the gas-generating effervescent system normally
consists of at lea;~t two components which react together to form gas.
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Whereas a numk>er of systems which, for example, release nitrogen,
oxygen or hydrogE~n may be used for this purpose, the effervescent system
used in the detergent ahaped bodies according to the invention is
preferably selected according to both economic and ecological criteria.
Preferred components b) consist of alkali metal carbonate and/or hydrogen
carbonate and an acidifying agent which is suitable for releasing carbon
dioxide from the alkali metal salts in aqueous solution.
Among the alkali nnetal carbonates and hydrogen carbonates, the
sodium and potassium salts are clearly preferred to the other salts for
reasons of cost. It is not of course necessary to use the corresponding
pure alkali metal carbonates or hydrogen carbonates. Instead, mixtures of
different carbonate's and hydrogen carbonates may be preferred from the
point of view of they washing process.
In preferred detergent shaped bodies, 2 to 20% by weight,
preferably 3 to 15'% by wE~ight and more preferably 5 to 10% by weight of
an alkali metal carbonate or hydrogen carbonate and 1 to 15% by weight,
preferably 2 to 12'% by weight and more preferably 3 to 10% by weight of
an acidifying agent, based on the shaped body as a whole, are used as
component b).
Suitable aciidifying agents, which release carbon dioxide from the
alkali metal salts in aqueous solution, include, for example, boric acid and
alkali metal hydrogen sulfates, alkali metal dihydrogen phosphates and
other inorganic salts. However, organic acidifying agents are preferably
used, citric acid being a particularly preferred acidifying agent. However,
the other solid mono-, oligo- and polycarboxylic acids in particular may also
be used. Within this group, tartaric acid, succinic acid, malonic acid, adipic
acid, malefic acid, fumaric acid, oxalic acid and polyacnylic acid are
preferred. Organic: sulfoni~:, acids, such as amidosulfonic acid, may also be
used. An acidifying agent which is commercially available and which may
also be used with advantage for the purposes of the present invention is
CA 02289305 1999-11-10
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Sokalan~ DCS (a trademark of BASF), a mixture of succinic acid (max.
31% by weight,) glutaric acid (max. 50% by weight) and adipic acid (max.
33% by weight).
According i:o the invention, preferred detergent shaped bodies are
those in which ~~ substance from the group of organic di-, tri- and
oligocarboxylic acids or mixtures thereof is used as acidifying agent in
component b).
The detergent shaped bodies according to the invention preferably
contain other typical detergent ingredients from the group of surfactants,
builders, bleaching agents,, bleach activators, enzymes, optical brighteners,
foam inhibitors, perfumes and dyes. These ingredients are described in
more detail in the following.
Anionic, nonionic, cationic and/or amphoteric surfactants may be
used in the detergent shaped bodies according to the invention. From the
performance poinl: of vievu, it is preferred to use mixtures of anionic and
nonionic surfactants in which the percentage content of anionic surfactants
should be greater 'than that of the nonionic surfactants. The total surfactant
content of the shaped bodies is between 5 and 60% by weight, based on
the weight of the shaped body, surfactant contents of more than 15% by
weight being preferred.
Suitable aniionic surfactants are, for example, those of the sulfonate
and sulfate type. Suitable surfactants of the sulfonate type are preferably
C9_~3 alkyl benzenE~sulfonates, olefin sulfonates, i.e. mixtures of alkene and
hydroxyalkane sulfonates, and the disulfonates obtained, for example, from
C~Z_~$ monoolefins with an internal or terminal double bond by sulfonation
with gaseous sulfur trioxide and subsequent alkaline or acidic hydrolysis of
the sulfonation products. Other suitable surfactants of the sulfonate type
are the alkane sulfonate:~ obtained from C~2_~$ alkanes, for example by
sulfochlorination or sulfoxidation and subsequent hydrolysis or
neutralization. The esters of a-sulfofatty acids (ester sulfonates), for
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example the a-sullfonated methyl esters of hydrogenated coconut oil, palm
kernel oil or tallow fatty acids, are also suitable.
Other suitable anionic surfactants are sulfonated fatty acid glycerol
esters. Fatty acid glycerol esters in the context of the present invention are
5 the monoesters, diesters, and triesters and mixtures thereof which are
obtained where production is carried out by esterification of a monoglycerol
with 1 to 3 moles of fatty acid or in the transesterification of triglycerides
with 0.3 to 2 moles of glycerol. Preferred sulfonated fatty acid glycerol
esters are the sul~fonation products of saturated fatty acids containing 6 to
10 22 carbon atoms, for example caproic acid, caprylic acid, capric acid,
myristic acid, lauri~c acid, palmitic acid, stearic acid or behenic acid.
Preferred ;alk(en)yl sulfates are the alkali metal salts and, in
particular, the sodium salts of the sulfuric acid semiesters of C~2_~$ fatty
alcohols, for example cocofatty alcohol, tallow fatty alcohol, lauryl,
myristyl,
cetyl or stearyl alcohol, or C~o_2o oxoalcohols and the corresponding
semiesters of secondary alcohols with the same chain length. Other
preferred alk(en)yl sulfates are those with the chain length mentioned
which contain a synthetic, linear alkyl chain based on a petrochemical and
which are similar in their degradation behavior to the corresponding
compounds based on olE:ochemical raw materials. C~2_~s alkyl sulfates,
C~2-~5 alkyl sulfates and G~a-~5 alkyl sulfates are preferred from the point
of
view of washing l:echnology. Other suitable anionic surfactants are 2,3-
alkyl sulfates which may k>e produced, for example, in accordance with US
3,234,258 or US 5,075,041 and which are commerially obtainable as
products of the Shell Oil Company under the name of DAN~.
The sulfuric: acid rnonoesters of linear or branched C~_2~ alcohols
ethoxylated with 1 to 6 moles of ethylene oxide, such as 2-methyl-branched
C9_~~ alcohols containing .on average 3.5 moles of ethylene oxide (EO) or
C~2_~$ fatty alcohols containing 1 to 4 EO, are also suitable. In view of
their
high foaming capacity, they are only used in relatively small quantities, for
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example in quantities of 1 to 5% by weight, in detergents.
Other preferred anionic surfactants are the salts of alkyl
sulfosuccinic acid which are also known as sulfosuccinates or as
sulfosuccinic acid esters and which represent monoesters and/or diesters
of sulfosuccinic acid with alcohols, preferably fatty alcohols and, more
particularly, ethoxylated fatty alcohols. Preferred sulfosuccinates contain
C$_~8 fatty alcohol residues or mixtures thereof. Particularly preferred
sulfosuccinates contain a~ fatty alcohol residue derived from ethoxylated
fatty alcohols which, considered in isolation, represent nonionic surfactants
(for a description, see below). Of these sulfosuccinates, those of which the
fatty alcohol residues are derived from narrow-range ethoxylated fatty
alcohols are particularly preferred. Alk(en)yl succinic acid preferably
containing 8 to 18 carbon atoms in the alk(en)yl chain or salts thereof may
also be used.
Other suitable anionic surfactants are, in particular, soaps. Suitable
soaps are saturated fatty acid soaps, such as the salts of lauric acid,
myristic acid, palmitic acid, stearic acid, hydrogenated erucic acid and
behenic acid, and soap mixtures derived in particular from natural fatty
acids, for example coconut oil, palm kernel oil or tallow fatty acids.
The anionic: surfactants, including the soaps, may be present in the
form of their sodium, potassium or ammonium salts and as soluble salts of
organic bases, such as mono-, di- or triethanolamine. The anionic
surfactants are preferably present in the form of their sodium or potassium
salts and, more preferably, in the form of their sodium salts.
Preferred nonionic surfactants are alkoxylated, advantageously
ethoxylated, more especially primary alcohols preferably containing 8 to 18
carbon atoms and, on average, 1 to 12 moles of ethylene oxide (EO) per
mole of alcohol, in which the alcohol radical may be linear or, preferably,
methyl-branched in the 2-position or may contain linear and methyl-
branched radicals in the form of the mixtures typically present in oxoalcohol
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radicals. However, alcohol ethoxylates containing linear radicals of
alcohols of native origin with 12 to 18 carbon atoms, for example coconut
oil, palm oil, tallow fatty or oleyl alcohol, and on average 2 to 8 EO per
mole of alcohol acre particularly preferred. Preferred ethoxylated alcohols
include, for exam~~le, C~2_~4 alcohols containing 3 EO or 4 EO, C9_» alcohol
containing 7 EO, C~3-~5 alcohols containing 3 EO, 5 EO, 7 EO or 8 EO,
C~2_~$ alcohols containing 3 EO, 5 EO or 7 EO and mixtures thereof, such
as mixtures of C~2_~4 alcohol containing 3 EO and C~2_~$ alcohol containing
5 EO. The degrees of ethoxylation mentioned represent statistical mean
values which, for a specual product, can be a whole number or a broken
number. Preferred alcohol ethoxylates have a narrow homolog distribution
(narrow range ethoxylates, NRE). In addition to these nonionic surfactants,
fatty alcohols containing more than 12 EO may also be used, examples
including tallow fatty alcohol containing 14 EO, 25 EO, 30 EO or 40 EO.
In addition, alkyl glycosides corresponding the general formula
RO(G)X where R is a primary, linear or methyl-branched, more particularly
2-methyl-branchecl, aliphatic radical containing 8 to 22 and preferably 12 to
18 carbon atoms and G stands for a glycose unit containing 5 or 6 carbon
atoms, preferably glucose, may also be used as further nonionic
surfactants. Thf~ degree of oligomerization x, which indicates the
distribution of monoglycosides and oligoglycosides, is between 1 and 10
and preferably befiNeen 1.2 and 4.
Another claws of preferred nonionic surfactants which may be used
either as sole nonionic surfactant or in combination with other nonionic
surfactants are alkoxylatE~d, preferably ethoxylated or ethoxylated and
propoxylated, fatty acid alkyl esters preferably containing 1 to 4 carbon
atoms in the alkyl ~;,hain, more especially the fatty acid methyl esters which
are described, for example, in Japanese patent application JP 581217598
or which are preferably produced by the process described in International
patent application IJVO-A-90113533.
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Nonionic surfactants of the amine oxide type, for example N-
cocoalkyl-N,N-dimethylamine oxide and N-tallowalkyl-N,N-dihydroxyethyl-
amine oxide, and the fatty acid alkanolamide type are also suitable. The
quantity in which these nonionic surfactants are used is preferably no more
than the quantity in which the ethoxylated fatty alcohols are used and,
more preferably, no more 'than half that quantity.
Other suitable surfactants are polyhydroxyfatty acid amides
corresponding to f~~rmula (I):
R'
R-CO-N-[Z] (I)
in which RCO is am aliphatic acyl group containing 6 to 22 carbon atoms,
R' is hydrogen, an alkyl or hydroxyalkyl group containing 1 to 4 carbon
atoms and [Z] is a~ linear or branched polyhydroxyalkyl group containing 3
to 10 carbon atom: and 3 to 10 hydroxyl groups. The polyhydroxyfatty acid
amides are known substances which may normally be obtained by
reductive amination of a rE~ducing sugar with ammonia, an alkylamine or an
alkanolamine and subsequent acylation with a fatty acid, a fatty acid alkyl
ester or a fatty acid chloride.
The group of polyhydroxyfatty acid amides also includes compounds
corresponding to formula (II):
R'-O-R2
R-C O-N-[Z] ( I I )
in which R is a linear or branched alkyl or alkenyl group containing 7 to 12
carbon atoms, R' is a linear, branched or cyclic alkyl group or an aryl group
containing 2 to 8 carbon atoms and R2 is a linear, branched or cyclic alkyl
group or an aryl grnup or an oxyalkyl group containing 1 to 8 carbon atoms,
CA 02289305 1999-11-10
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C~~ alkyl or phenyl groups being preferred, and [Z] is a linear polyhydroxy-
alkyl group, of which the ;~Ikyl chain is substituted by at least two hydroxyl
groups, or alkoxylated, preferably ethoxylated or propoxylated, derivatives
of that group.
[Z] is preferably obi;ained by reductive amination of a reduced sugar,
for example glucose, fructose, maltose, lactose, galactose, mannose or
xylose. The N-alhoxy- or N-aryloxy-substituted compounds may then be
converted into the required polyhydroxyfatty acid amides by reaction with
fatty acid methyl esters iin the presence of an alkoxide as catalyst, for
example in accordance with the teaching of International patent application
WO-A-95/07331.
Silicates, aluminium silicates (especially zeolites), carbonates, salts
of organic di- and polycarboxylic acids and mixtures of these substances
are mentioned in particular as builders which may be present in the
detergent shaped bodies according to the invention.
Suitable cr,~stalline layer-form sodium silicates correspond to the
general formula N~~2MSiXO2X+~~ y H20, where M is sodium or hydrogen, x is
a number of 1.9 to 4 and y is a number of 0 to 20, preferred values for x
being 2, 3 or 4. Crystalline layer silicates such as these are described, for
example, in European patent application EP-A-0 164 514. Preferred
crystalline layer silicates corresponding to the above formula are those in
which M is sodium and x assumes the value 2 or 3. Both [3- and 8-sodium
disilicates Na2Si2O5~ y H;>Oare particularly preferred, [i-sodium disilicate
being obtainable, for example, by the process described in International
patent application 'WO-A- !91108171.
Other useful builders are amorphous sodium silicates with a
modulus (Na20:Si02 ratio) of 1:2 to 1:3.3, preferably 1:2 to 1:2.8 and more
preferably 1:2 to 1:2.6 which dissolve with delay and exhibit multiple wash
cycle properties. The delay in dissolution in relation to conventional
amorphous sodiunn silicates can have been obtained in various ways, for
CA 02289305 1999-11-10
example by surface treatnnent, compounding, compacting or by overdrying.
In the context of the invention, the term ~amorphous0 is also understood to
encompass ~X-ray amorphous0. In other words, the silicates do not
produce any of the sharp X-ray reflexes typical of crystalline substances in
5 X-ray diffraction experiments, but at best one or more maxima of the
scattered X-radiation which have a width of several degrees of the
diffraction angle. However, particularly good builder properties may even
be achieved where the silicate particles produce crooked or even sharp
diffraction maxima in electron diffraction experiments. This may be
10 interpreted to mean that the products have microcrystalline regions
between 10 and a~ few hundred nm in size, values of up to at most 50 nm
and, more particu'~larly, up to at most 20 nm being preferred. So-called X-
ray amorphous sillicates such as these, which also dissolve with delay in
relation to conventional waterglasses, are described for example in
15 German patent application DE-A-44 00 024. Compacted amorphous
silicates, compounded amorphous silicates and overdried X-ray-
amorphous silicatE~s are particularly preferred.
The finely crystalline, synthetic zeolite containing combined water
used in accordance with the invention is preferably zeolite A and/or zeolite
P. Zeolite MAP° (Crosfileld) is a particularly preferred P-type
zeolite.
However, zeolite :K and mixtures of A, X and/or P are also suitable. The
zeolite may be used as a spray-dried powder or even as an undried
suspension still moist from its producrtion. If the zeolite is used in the
form
of a suspension, vthe suspension may contain small additions of nonionic
surfactants as stabilizers, for example 1 to 3% by weight, based on zeolite,
of ethoxylated C~2..~$ fatty alcohols containing 2 to 5 ethylene oxide groups,
C12-14 fatty alcohols containing 4 to 5 ethylene oxide groups or ethoxylated
isotridecanols. Suitable zeolites have a mean particle size of less than 10
~m (volume distribution, as measured by the Coulter Counter Method) and
contain preferably 18 to 22% by weight and more preferably 20 to 22% by
CA 02289305 1999-11-10
16
weight of combined water.
The generally known phosphates may of course also be used as
builders providing their use should not be avoided on ecological grounds.
The sodium salt: of the orthophosphates, the pyrophosphates and, in
particular, the tripolyphos~>hates are particularly suitable.
Useful organic builders are, for example, the polycarboxylic acids
usable, for examyle, in the form of their sodium salts, such as citric acid,
adipic acid, succinic acid, glutaric acid, tartaric acid, sugar acids, amino-
carboxylic acids, nitrilotriiacetic acid (NTA), providing their use is not
ecologically unsafe, and mixtures thereof. Preferred salts are the salts of
the polycarboxylic: acids, such as citric acid, adipic acid, succinic acid,
glutaric acid, tartaric acid, sugar acids and mixtures thereof. These salts
are used for their (building properties and should not be regarded as part of
the effervescent ;system, especially since the salts are not suitable for
releasing carbon clioxide, for example from hydrogen carbonates.
Among they compounds yielding HZOZ in water which serve as
bleaching agents, sodium perborate tetrahydrate and sodium perborate
monohydrate are particularly important. Other useful bleaching agents are,
for example, sodium perc;arbonate, peroxypyrophosphates, citrate perhy-
drates and HZO2-yielding peracidic salts or peracids, such as
perbenzoates, peroxophthalates, diperazelaic acid, phthaloiminoperacid or
diperdodecane dioic acid.
In order to obtain an improved bleaching effect where washing is
carried out at temperatures of 60°C or lower, bleach activators may be
incorporated as a component as such or as an ingredient of component b).
The bleach actiivators may be compounds which form aliphatic
peroxocarboxylic .acids containing preferably 1 to 10 carbon atoms and
more preferably 2 to 41 carbon atoms and/or optionally substituted
perbenzoic acid under perhydrolysis conditions. Substances bearing O-
and/or N-acyl groups with the number of carbon atoms mentioned and/or
CA 02289305 1999-11-10
17
optionally substituted benzoyl groups are suitable. Preferred bleach
activators are pol~~acylate~d alkylenediamines, more particularly tetraacetyl
ethylenediamine I;TAED), acylated triazine derivatives, more particularly
1,5-diacetyl-2,4-di~oxohexahydro-1,3,5-triazine (DADHT), acylated
glycolurils, more particul<~rly tetraacetyl glycoluril (TAGU), N-acylimides,
more particularly N-nonanoyl succinimide (NOSI), acylated phenol
sulfonates, more particularly n-nonanoyl or isononanoyloxybenzene-
sulfonate (n- or iso-NOBS), carboxylic anhydrides, more particularly
phthalic anhydride, acylated polyhydric alcohols, more particularly triacetin,
ethylene glycol diacetate and 2,5-diacetoxy-2,5-dihydrofuran.
In addition to or instead of the conventional bleach activators
mentioned above, so-called bleach catalysts may also be incorporated in
the shaped bodies, according to the invention. Bleach catalysts are bleach-
boosting transition metal salts or transition metal complexes such as, for
example, manganese-, iron-, cobalt-, ruthenium- or molybdenum-salen
complexes or carbonyl complexes. Manganese, iron, cobalt, ruthenium,
molybdenum, titanium, vanadium and copper complexes with nitrogen-
containing tripod ligands dud cobalt-, iron-, copper- and ruthenium-ammine
complexes may al:~o be used as bleach catalysts.
Suitable foam inhibitors - which may form part of component b) or
may be used on their own as component b) - are, for example, soaps of
natural or synthetic origin which have a high percentage content of C~8_24
fatty acids. Suitalble non-surface-active foam inhibitors are, for example,
organopolysiloxan~~s and mixtures thereof with microfine, optionally
silanized, silica or bis-stearyl ethylenediamide. Mixtures of different foam
inhibitors, for example mixtures of silicones, paraffins and waxes, may also
be used with advantage. The foam inhibitors are preferably fixed to a
granular water-soluble or water-dispersible support. Mixtures of paraffins
and bis-stearyl ethylenediamides are particularly preferred.
In addition, the detergent shaped bodies according to the invention
CA 02289305 1999-11-10
18
may also contain components with a positive effect on the removability of
oil and fats from fiextiles by washing (so-called soil repellents). This
effect
becomes particularly clear when a textile which has already been
repeatedly washed with a detergent according to the invention containing
this oil- and fat-dlissolving component is soiled. Preferred oil- and fat-
dissolving components include, for example, nonionic cellulose ethers,
such as methyl cellulose <~nd methyl hydroxypropyl cellulose containing 15
to 30% by weight of methoxyl groups and 1 to 15% by weight of hydroxy-
propoxyl groups, based on the nonionic cellulose ether, and the polymers
of phthalic acid and/or terephthalic acid known from the prior art or
derivatives thereof, more particularly polymers of ethylene terephthalates
and/or polyethylene glycol terephthalates or anionically and/or nonionically
modified derivatives thereof. Of these, the sulfonated derivatives of
phthalic acid and terephthalic acid polymers are particularly preferred.
Suitable enzymes are those from the class of proteases, lipases,
amylases, cellulases or mixtures thereof. Enzymes obtained from bacterial
strains or fungi, such as Bacillus subtilis, Bacillus licheniformis and
Streptomyces griseus, are: particularly suitable. Proteases of the subtilisin
type are preferred, proteases obtained from Bacillus lentus being
particularly preferred. Enzyme mixtures, for example of protease and
amylase or protease and lipase or protease and cellulase or of cellulase
and lipase or of protease, amylase and lipase or of protease, lipase and
cellulase, but especially cellulase-containing mixtures, are of particular
interest. Peroxidases or oxidases have also proved to be suitable in some
cases. The enzymes may be adsorbed to supports and/or encapsulated in
shell-forming substances t;o protect them against premature decomposition.
The percentage content of the enzymes, enzyme mixtures or enzyme
granules in the shaped bodies according to the invention may be, for
example, from about 0.1 to 10% by weight and is preferably from 0.5 to
about 5% by weight.
CA 02289305 1999-11-10
19
The shaped bodies may contain derivatives of diamino-
stilbenzenedisulfonic acid or alkali metal salts thereof as optical
brighteners. Suitable optical brighteners are, for example, salts of 4,4'-bis-
(2-anilino-4-morph~olino-1,3,5-triazinyl-6-amino)-stilbene-2,2'-disulfonic
acid
or compounds of similar composition which contain a diethanolamino
group, a methylarnino group, an anilino group or a 2-methoxyethylamino
group instead of the morpholino group. Brighteners of the substituted
Biphenyl styryl type, for example alkali metal salts of 4,4'-bis-(2-
sulfostyryl)-
diphenyl, 4,4'-bis-(4-chloro-3-sulfostyryl)-Biphenyl or 4-(4-chlorostyryl)-4'-
(2-
sulfostyryl)-Biphenyl, may also be present. Mixtures of the brighteners
mentioned above may also be used.
In another ~embodirnent, the present invention relates to a process
for producing the detergent shaped bodies according to the invention by
compressing a particulate detergent containing surfactant(s), builders and
optionally other detergent ingredients, the detergent to be compressed
additionally containing
a) 1 to 10% by weight of one or more swellable water-insoluble disinte-
gration aids and
b) 3 to 60% by weight of a gas-generating effervescent system,
based on the sha~~ed body formed, components a) and b) optionally being
compounded with other ingredients of the detergent or being separately
incorporated.
The particulate compound (premix) to be compressed may be
present as a pure powder mixture containing components a) and b),
although individual raw materials are preferably introduced into the
compound in pretreated and, more particularly, precompacted form. In one
particular embodirnent, the disintegration aids are preferably introduced
into the compound in the form of granules, pellets, compactates or
extrudates. The Name alao applies to certain other ingredients, such as
CA 02289305 1999-11-10
surfactants, which may be introduced into the compound in the form of
advantageously builder-containing particles obtainable by spray drying,
granulation, pelleting, compacting or extrusion.
In preferred embodiments of the process according to the invention,
5 the particulate detergent composition is compressed at temperatures below
30°C and under pressure below 15 N/cmz. The actual production of the
shaped bodies according to the invention is carried out by initially dry-
mixing the ingredients, which may be completely or partly pregranulated,
and then convE~rting the resulting mixture, more particularly by
10 compression, into tablets using conventional methods (for example as
described in the conventional patent literature on tabletting, above all in
the
field of detergents, more particularly as described in the above-mentioned
patent applications and the Article entitled "Tablettierung: Stand der
Technik", SOFW-Journal, Vol. 122, pp 1016-1021 (1996)).
15 The shaped bodies can be made in predetermined three-
dimensional forms. and predetermined sizes. Suitable three-dimensional
forms are virtually any easy-to-handle forms including, for example, slabs
or bars, cubes, squares and corresponding three-dimensional elements
with flat sides and, more particularly, cylindrical forms with a circular or
oval
20 cross-section. This particular three-dimensional form encompasses tablets
and compact cylinders with a height-to-diameter ratio of more than 1.
The portion shaped bodies may be formed as separate individual
elements which correspond to a predetermined dose of the detergent.
However, it is also possible to form shaped bodies which combine several
such units in a single shaped body, individual portioned units being easy to
break off in particular through the provision of predetermined weak spots.
For the use of laundry detergents in machines of the standard European
type with horizons:ally arranged mechanics, it can be of advantage to
produce the portioned shaped bodies as cylindrical or square tablets,
preferably with a diameter-to-height ratio of about 0.5:2 to 2:0.5.
CA 02289305 1999-11-10
21
Commercially available hydraulic presses, eccentric presses and rotary
presses are particularly suitable for the production of shaped bodies such
these.
The three-dimensional form of another embodiment of the shaped
bodies according to the invention is adapted in its dimensions to the
dispensing compartment of commercially available domestic washing
machines, so that the shaped bodies can be introduced directly, i.e. without
a dosing aid, into the dispensing compartment where they dissolve on
contact with water. However, it is of course readily possible - and preferred
in accordance with the present invention - to use the detergent shaped
bodies in conjunctlion with a dosing aid.
Another preferred shaped body which can be produced has a plate-
like or slab-like structure with alternately thick long segments and thin
short
segments, so that individual segments can be broken off from this "bar" at
the predetermined) weak :,pots, which the short thin segments represent,
and introduced into the machine. This "bar" principle can also be
embodied in other geomE~tric forms, for example vertical triangles which
only joined to one another at one of their longitudinal sides.
In another possible embodiment, however, the various components
are not compressed to form a single tablet, instead the shaped bodies
obtained comprise several layers, i.e. at least two layers. These various
layers may have different dissolving rates. This can provide the shaped
bodies with favorable performance properties. If, for example, the shaped
bodies contain components which adversely affect one another, one
component may bE~ integrated in the more quickly dissolving layer while the
other component rnay be incorporated in a more slowly dissolving layer so
that the first comlponent can already have reacted off by the time the
second component dissolves. The various layers of the shaped bodies can
be arranged in the form of a stack, in which case the inner layers) dissolve
at the edges of the shaped body before the other layers have completely
CA 02289305 1999-11-10
22
dissolved. Alternatively, however, the inner layers) may also be
completely surrounded by the layers lying further to the outside which
prevents constituents of the inner layers) from dissolving prematurely.
In another preferred embodiment of the invention, a shaped body
consists of at least three layers, i.e. two outer layers and at least one
inner
layer, a peroxy bleaching agent being present in at least one of the inner
layers whereas, in the case of the stack-like tablet, the two cover layers
and, in the case of the envelope-like tablet, the outermost layers are free
from peroxy bleaching agent. In another possible embodiment, peroxy
bleaching agent ;end any bleach activators or bleach catalysts present
and/or enzymes nnay be ;spatially separated from one another in one and
the same shaped body. llAultilayer shaped bodies such as these have the
advantage that thE:y can be used not only via a dispensing compartment or
via a dosing unit which is added to the wash liquor, instead it is also
possible in cases such as these to introduce the shaped body into the
machine in direct contact with the fabrics without any danger of spotting by
bleaching agent on the likes.
Similar efl~ects can also be obtained by coating individual
constituents of the: detergent composition to be compressed or the shaped
body as a whole. To this end, the shaped bodies to be coated may be
sprayed, for example, with aqueous solutions or emulsions or a coating
may be obtained by the process known as melt coating.
The shaped bodies according to the invention, more particularly the
hitherto poorly di:~integrai:ing and poorly soluble detergent and bleaching
tablets, have excellent disintegration properties through the presence of
water-insoluble, :>wellable disintegration aid and effervescent system
components a) and b)}. This can be tested, for example, under critical
conditions in a standard domestic washing machine (direct introduction into
the wash liquor by a conventional dosing unit, delicates program or
coloreds program, washing temperature max. 40°C).
CA 02289305 1999-11-10
23
In another embodirnent, therefore, the present invention relates to a
washing process in which the shaped body is introduced into the wash
liquor from the di;>pensing compartment of a domestic washing machine.
The dissolving times of the shaped bodies in the washing machine are
preferably less than 8 minutes and more preferably less than 5 minutes. In
another embodimE:nt, the invention relates to a washing process in which
the shaped body is placed directly - optionally using a dosing aid - on the
laundry loaded into the drum of a domestic washing machine. In this case,
the shaped body may advantageously be added to the washing directly, i.e.
without an additional dosing aid. However, known dosing aids, such as
bags, sachets, plastic containers and the like, may also readily be used.
Examples
Detergent :>haped bodies 1 and 2 according to the invention and
comparison shaped bodies 3 and 4 which have the composition shown in
Table 1 were produced by compressing a particulate detergent
composition.
The comparison shaped bodies contained either no component a)
(Example 3) or no component b) (Example 4), small quantities of Na2C03
being used as buil~~er.
CA 02289305 1999-11-10
24
Table 1
Detergent shaped bodies [% by weight]
Detergent shaped body 1 2 3 4
C9_,3 Alkyl benzene:~ulfonate 11.4 10.0 10.6 10.0
C,2_,S Fatty alcohol ;>ulfate - 6.6 2.4 6.8
C,z_,8 Fatty alcohol ~ 7E0 5.8 - 4.8 6.2
Soap 0.7 2.1 1.6 1.8
Sodium tripolyphosphate - 23.5 - -
Zeolite 4A (based on water-free18.5 3.5 20.0 20.0
substance)
Sodium perborate 18.2 - 18.6 18.6
Sodium percarbonaile - 23.0 - -
Tetraacetyl ethylenediamine 6.4 3.4 5.8 5.8
(TAED)
Cellulose {component a)} 3.4 4.0 - 6.0
Citric acid {constituent of 3.2 3.5 3.5 -
cornponent b)}*
Na2C03 {constituent: of component8.6 - 8.1 6.3
b)}*
NaHC03 {constituent of component6.4 7.0 6.8 -
b)}*
Amorphous sodium silicate 3.3 2.1 3.0 3.4
Acrylic acid/maleic acid copolymer2.7 2.5 2.5 2.6
Enzymes 2.3 4.0 2.7 2.7
Brightener 0.2 0.2 0.2 0.2
Polyethylene glycol (molecular - 0.5 - -
weight ca.
4000 g/mol)
Salts/water BalanceBalanceBalanceBalance
") separately incorporated
The hardness of the tablets was measured by deforming the tablets
until they broke, the force being applied to the sides of the tablets and the
maximum force the: tablets, withstood being determined.
To determine tablet disintegration, a tablet was placed in a glass
beaker filled with water (600 ml of water, temperature 30°C) and the
time
which the tablet took to disintegrate completely was measured.
For the dis~pensincl test, three 40 g tablets were placed in the
dispensing compartment of the washing machine used. After the
CA 02289305 1999-11-10
dispensing phase, the residue in the compartment was dried and weighed.
The experirnental data are shown in Table 2.
Table 2
Detergent tablets [physical data]
Tablet Example Example Example Example
1 2 3 4
Tablet hardness 33 N 24 N 30-35 30-35 N
N
Tablet disintegration5-10 secs.5-10 secs.> 5 mins.3 mins.
Residue - - 34 g 12 g
