Note: Descriptions are shown in the official language in which they were submitted.
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1
Process for the preparation of microencapsulated
enzymes
Field of the Invention
The present invention relates to a process for the
preparation of microencapsulated enzymes, to the use of
these enzymes in detergents and cleaners, and to a
detergent and cleaner.
Background of the Invention
Enzymes for further industrial processing are generally
supplied as liquid enzyme concentrates which are
isolated from a fermentation broth and supplied in
concentrated form. The stability of the enzymes in an
aqueous environment is only limited. In order to
convert the resulting enzyme concentrates into an
anhydrous form, the concentrate can be spray dried e.g.
in the presence of a polymeric binder, wherein the
dried enzyme particles are taken up by the binder and
aggregates form. To prepare liquid preparations, the
spray-dried particles are redispersed.
A process for the preparation of enzyme dispersions is
disclosed in WO 94/25560. The process described therein
involves the emulsification of an enzyme preparation in
a water-immiscible liquid in the presence of a
polymeric dispersion stabilizer, forming a stable
dispersion of the aqueous enzyme particles which, in
the anhydrous state, have a particle size with a
diameter of less than 30 ~,m, and dehydration of the
dispersed particles by azeotropic distillation. The
essential feature of the process described is that,
before, during or after the dehydration of the
particles, an organic liquid, which is less volatile
than the water-immiscible liquid and which is_ chosen
from surfactants and water-miscible liquids, is added
to the dispersion, and the water-immiscible liquid is
distilled off from the dispersion until the amount of
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this initially introduced water-immiscible liquid in
the dispersion which remains is below 20% by weight,
based on the liquid phase of the dispersion.
International patent application WO 97/24177 discloses
a detergent concentrate suitable for dilution with
water which consists of a liquid detergent phase and
enzyme-containing particles dispersed therein. Here, at
least 90% by weight of the enzyme-containing particles
should have a diameter of less than 30 ~m and consist
for their part of a shell prepared from a condensation
polymer and permeable to water and compounds of low
molecular weight, and of a core representing the enzyme
component. The essential feature here is that the core
does not itself consist only of enzyme, but also of a
detergent phase which is in equilibrium with the
surrounding liquid, and a core polymer where, in the
moment when, for the preparation of the wash liquid,
the claimed detergent concentrate is diluted with
water, this water passes osmotically into the particle
core and cooperates with the water which is already
present therein in order to allow the particle to swell
by at least 1.2-fold in diameter, as a result of which
the enzyme is released into the wash water at the
moment of dilution. This document thus concerns itself
essentially with making possible a biophysically
optimal release process. The actual enzyme formulation
is secondary here.
The preparation of enzymes in pulverulent form, for
example by spray drying or else by crystallization
processes, frequently leads to very fine powders with
particle sizes below 20 ~m which, because of the
possible formation of dust, entails health risks as a
result of the inhalation of the dust during preparation
and processing. Added to this is the fact that in the
case of these drying processes some of the enzymatic
activity can be lost as a result of denaturation.
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An important field of application for enzymes is
detergents and cleaners. In these compositions, the
enzymes are either incorporated as solid constituents
or in the form of liquid formulations.
In the preparation of liquid detergents and cleaners,
it is particularly advantageous and cost-effective if
the starting materials are also present in liquid or
dispersed form. For the use of the enzymes, the direct
use of the enzyme concentrates obtained from the
preparation presents itself. However, these concen-
trates have a relatively high water content . In liquid
formulations there is also the danger that the enzymes
will at least partially lose their activity.
Liquid bleach-containing formulations require the water
content to be only low in order to stabilize the
bleach. This means that the water content of the raw
materials used must accordingly be low.
Accordingly, the object of the present invention was to
provide a preparation form for enzymes in which the
enzymes are stabilized and which can be incorporated
into detergents and cleaners without the enzyme
activity being significantly reduced.
Surprisingly, it has been found that enzymes can be
stabilized in a simple manner by microencapsulating
them using aqueous starch solutions or starch
emulsions; they can then be added to the detergents and
cleaners either as microemulsions or in the form of
spray-dried products.
Summary of the Invention
The present invention provides, accordingly, a process
for the preparation of microencapsulated enzymes which
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comprises mixing together and dispersing a starch
solution or starch emulsion and an enzyme solution.
Detailed Description of the Invention
For the preparation of microencapsulated enzymes or
enzyme preparations, water-soluble or water-
emulsifiable starches or starch derivatives, such as,
for example, hydrophobicized starches, are suitable.
Examples of such starch derivatives are maltodextrins,
glucose syrups or dehydrated glucose or octenyl
succinate starches. Suitable starches are available
commercially e.g. under Narlex~ ST2 (National Starch)
or Cleargum CO O1~ (Roquette).
The enzymes can be chosen from any enzymes customary
for detergents and cleaners. Suitable enzymes are
primarily the proteases, lipases, amylases and/or
cellulases obtained from microorganisms, such as
bacteria or fungi, preference being given to proteases
derived and/or produced from Bacillus species, and to
their mixtures with amylases. They are obtained from
suitable microorganisms in a known manner by
fermentation processes which are described, for
example, in the German laid-open specifications
DE 19 40 488, DE 20 44 161, DE 22 O1 803 and DE 21
21 397, the US American patent specifications
US 3 632 957 and US 4 264 738, the European patent
application EP 006 638, and the International patent
application WO 91/912792. If the preparation prepared
in accordance with the invention is a protease-
containing preparation, the protease activity is
preferably 150 000 protease units (PU, determined in
accordance with the method described in Tenside
[surfactants], vol. 7 (1970), pp. 125-132) to
350 000 PU, in particular 160 000 PU to 300 000 PU,
per gram of preparation.
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The enzyme solutions are preferably used as enzyme
concentrates, as can be obtained, for example, by
processes known from the prior art, e.g. by micro-
filtration or ultrafiltration. If the enzyme con-
s centrates are protease concentrates, then the protease
activity can amount to 1 500 000 PU.
To carry out the process according to the invention, a
concentrated, aqueous enzyme solution and a starch
solution are preferably firstly mixed with one another,
and the enzyme solution is finely dispersed within the
starch solution using a dispersion device . As a result
of this process, the enzymes are surrounded by starch
molecules and thereby stabilized.
The microencapsulated enzymes obtained according to the
invention can be passed to their intended uses in the
form of their dispersions or as concentrated products
in a manner known per se and be further processed
there.
If the microencapsulated enzymes are to be processed in
solid form, then the water can be removed using
processes known from the prior art, such as spray
drying, centrifugation or by resolubilization. The
particles obtained usually have a particle size between
50 and 200 ~,m.
In a preferred embodiment the microencapsulated enzymes
are used in detergents and cleaners.
The present invention, accordingly, further provides
for the use of the microencapsulated enzymes obtained
by the process described above in detergents and
cleaners, preferably in liquid to gelatinous bleach-
containing detergents and cleaners.
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The present invention also provides detergents and
cleaners which comprise surfactants and builder
substances, and optionally further customary
ingredients, which are notable for the fact that they
comprise microencapsulated enzymes as can be obtained
by the process described above.
The compositions according to the invention comprise
surfactants, e.g. nonionic, anionic and amphoteric
surfactants, and bleaches, and optionally further
customary ingredients.
The nonionic surfactants used are preferably
alkoxylated, advantageously ethoxylated, in particular
primary alcohols having, preferably, 8 to 18 carbon
atoms and, on average, 1 to 12 mol of ethylene oxide
(EO) per mole of alcohol, in which the alcohol radical
can be linear or, preferably, methyl-branched in the
2-position, or can comprise linear and methyl-branched
radicals in a mixture as are customarily present in oxo
alcohol radicals. Particular preference is, however,
given to alcohol ethoxylates containing linear radicals
of alcohols of a native origin having 12 to 18 carbon
atoms, e.g. from coconut, palm, tallow fatty or oleyl
alcohol, and, on average, 2 to 8 EO per mole of
alcohol. Preferred ethoxylated alcohols include, for
example, Clz-14-alcohols having 3 EO or 4 EO,
C9_11-alcohol having 7 EO, Cls-ls-alcohols having 3 EO,
5 EO, 7 EO or 8 E0, Clz-ls-alcohols having 3 E0, 5 EO or
7 EO and mixtures of these, such as mixtures of
Clz-i4-alcohol with 3 EO and Clz-ls-alcohol having 5 EO.
The degrees of ethoxylation given are statistical
average values which can be an integer or a fraction
for a specific product. Preferred alcohol ethoxylates
have a narrowed homolog distribution (narrow range
ethoxylates, NRE). In addition to these nonionic
surfactants, fatty alcohols having more than 12 EO can
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also be used. Examples thereof are tallow fatty alcohol
having 14 EO, 25 EO, 30 EO or 40 E0.
A further class of preferred nonionic surfactants,
which are used either as the sole nonionic surfactant
or in combination with other nonionic surfactants, are
alkoxylated, preferably ethoxylated or ethoxylated and
propoxylated fatty acid alkyl esters, preferably having
1 to 4 carbon atoms in the alkyl chain, in particular
fatty acid methyl esters.
A further class of nonionic surfactants which can
advantageously be used are the alkyl polyglycosides
(APG). Alkyl polyglycosides which can be used satisfy
the general formula RO(G)Z in which R is a linear or
branched, in particular methyl-branched in the
2-position, saturated or unsaturated, aliphatic radical
having 8 to 22, preferably 12 to 18 carbon atoms, and G
is the symbol which stands for a glucose unit having 5
or 6 carbon atoms, preferably for glucose. The degree
of glycosylation z is here between 1.0 and 4.0,
preferably between 1.0 and 2.0 and in particular
between 1.1 and 1.4. Preference is given to using
linear alkyl polyglucosides, i.e. alkyl polyglycosides
in which the polyglycosyl radical is a glucose radical,
and the alkyl radical is an n-alkyl radical.
Also, nonionic surfactants of the amine oxide type, for
example N-cocoalkyl-N,N-dimethylamine oxide and
N-tallow alkyl-N,N-dihydroxyethylamine oxide, and of
the fatty acid alkanolamide type may be suitable. The
proportion of these nonionic surfactants is preferably
no more than that of the ethoxylated fatty alcohols, in
particular no more than half thereof.
Further suitable surfactants are polyhydroxy fatty acid
amides of the formula (II)
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R1
R-CO-N- [Z] (II)
in which RCO is an aliphatic acyl radical having 6 to
22 carbon atoms, R1 is hydrogen, an alkyl or
hydroxyalkyl radical having 1 to 4 carbon atoms and [Z]
is a linear or branched polyhydroxyalkyl radical having
3 to 10 carbon atoms and 3 to 10 hydroxyl groups. The
polyhydroxy fatty acid amides are known substances
which can usually be obtained by reductive amination of
a reducing 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 polyhydroxy fatty acid amides also
includes compounds of the formula (III)
2 0 R1-O-RZ
R-CO-N-[Z] (III)
in which R is a linear or branched alkyl or alkenyl
radical having 7 to 12 carbon atoms, R1 is a linear,
branched or cyclic alkyl radical or an aryl radical
having 2 to 8 carbon atoms, and Rz is a linear,
branched or cyclic alkyl radical or an aryl radical or
an oxy-alkyl radical having 1 to 8 carbon atoms, where
C1_4-alkyl or phenyl radicals are preferred, and [Z] is
a linear polyhydroxyalkyl radical whose alkyl chain is
substituted by at least two hydroxyl groups, or
alkoxylated, preferably ethoxylated or propoxylated,
derivatives of this radical.
[Z] is preferably obtained by reductive amination of a
reducing sugar, for example glucose, fructose, maltose,
lactose, galactose, mannose or xylose. The N-alkoxy- or
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N-aryloxy-substituted compounds can then be converted,
for example by reaction with fatty acid methyl esters
in the presence of an alkoxide as catalyst, into the
desired polyhydroxy fatty acid amides.
The surfactants may be present in the cleaners or
detergents according to the invention in an overall
amount of from preferably 5% by weight to 50% by
weight, in particular from 8% by weight to 30% by
weight, based on the finished composition.
The anionic surfactants used are, for example, those of
the sulfonate and sulfate type. Suitable surfactants of
the sulfonate type are, preferably, C9-13-alkylbenzene-
sulfonates, olefin sulfonates, i.e. mixtures of alkene-
and hydroxyalkanesulfonates, and disulfonates, as
obtained, for example, from Clz-ls-monoolefins having a
terminal or internal double bond by sulfonation with
gaseous sulfur trioxide and subsequent alkaline or
acidic hydrolysis of the sulfonation products. Also
suitable are alkanesulfonates, which are obtained from
Clz-ls-alkanes, for example by sulfochlorination or
sulfoxidation with subsequent hydrolysis or
neutralization. Likewise suitable are also the esters
of a-sulfo fatty acids (ester sulfonates), e.g. the
a-sulfonated methyl esters of hydrogenated coconut,
palm kernel or tallow fatty acids.
Further suitable anionic surfactants are sulfated fatty
acid glycerol esters. Fatty acid glycerol esters is
understood as meaning the mono-, di- and triesters, and
mixtures thereof, as are obtained during the
preparation by esterification of a monoglycerol with 1
to 3 mol of fatty acid or during the trans-
esterification of triglycerides with 0.3 to 2 mol of
glycerol. Preferred sulfated fatty acid glycerol esters
are here the sulfation products of saturated fatty
acids having 6 to 22 carbon atoms, for example of
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caproic acid, caprylic acid, capric acid, myristic
acid, lauric acid, palmitic acid, stearic acid or
behenic acid.
Preferred alk(en)yl sulfates are the alkali metal, and
in particular the sodium, salts of sulfuric half-esters
of Clz-la-fatty alcohols, for example coconut fatty
alcohol, tallow fatty alcohol, lauryl, myristyl, cetyl
or stearyl alcohol or of Clo-Czo-oxo alcohols and those
half-esters of secondary alcohols of these chain
lengths. Further preferred are alk(en)yl sulfates of
said chain length which comprise a synthetic,
petroleum-based straight-chain alkyl radical which have
analogous degradation behavior to the equivalent
compounds based on fatty chemical raw materials. From a
washing performance viewpoint, preference is given to
Clz-Cls-alkyl sulfates and Clz-Cis-alkyl sulfates, and
C14-Cis-alkyl sulfates. 2,3-Alkyl sulfates are also
suitable anionic surfactants.
The sulfuric monoesters of straight-chain or branched
C~_zl-alcohols ethoxylated with 1 to 6 mol of ethylene
oxide, such as 2-methyl-branched C9_11-alcohols having,
on average, 3.5 mol of ethylene oxide (EO) or
Clz-la-fatty alcohols having 1 to 4 EO, are also
suitable. Because of their high foaming behavior, they
are used in cleaners only in relatively small amounts,
for example in amounts up to 5% by weight, usually from
1 to 5% by weight.
Further suitable anionic surfactants are also the salts
of alkylsulfosuccinic acid, which are also referred to
as sulfosuccinates or as sulfosuccinic esters and which
represent monoesters and/or diesters of sulfosuccinic
acid with alcohols, preferably fatty alcohols and, in
particular, ethoxylated fatty alcohols. Preferred
sulfosuccinates contain C$_18-fatty alcohol radicals or
mixtures thereof. In particular, preferred sulfo-
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succinates contain a fatty alcohol radical derived from
ethoxylated fatty alcohols, which are themselves
nonionic surfactants (see below for description). In
this connection, sulfosuccinates whose fatty alcohol
radicals are derived from ethoxylated fatty alcohols
having a narrowed homolog distribution are, in turn,
particularly preferred. Likewise, it is also possible
to use alk(en)ylsuccinic acid having, preferably, 8 to
18 carbon atoms in the alk(en)yl chain or salts
thereof.
Further suitable anionic surfactants are, in
particular, soaps. Saturated fatty acid soaps; such as
the salts of lauric acid, myristic acid, palmitic acid,
stearic acid, hydrogenated erucic acid and behenic
acid, and, in particular, soap mixtures derived from
natural fatty acids, e.g. coconut, palm kernel or
tallow fatty acids, are suitable.
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 in the form of their sodium
or potassium salts, in particular in the form of the
sodium salts.
Of the compounds which serve as bleaches and produce
H202 in water, sodium perborate tetrahydrate and sodium
perborate monohydrate are of particular importance.
Other bleaches which can be used are, for example,
sodium percarbonate, peroxypyrophosphates, citrate
perhydrates, and H202-producing peracidic salts or
peracids, such as perbenzoates, peroxophthalates,
diperazelaic acid, phthaloiminoperacid or
diperdodecanedioic acid. If bleaches are used it is
also possible to dispense with the use of surfactants
and/or builders, meaning that pure bleach tablets can
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be prepared. If such bleach tablets are to be used for
textile washing, a combination of sodium percarbonate
with sodium sesquicarbonate is preferred, irrespective
of which further ingredients are present in the
moldings. If cleaner or bleach tablets for machine
dishwashing are prepared, then it is also possible to
use bleaches from the group of organic bleaches.
Typical organic bleaches are diacyl peroxides, such as,
for example, dibenzoyl peroxide. Further typical
organic bleaches are the peroxy acids, specific
examples being alkylperoxy acids and arylperoxy acids.
Preferred representatives are (a) peroxybenzoic acid
and its ring-substituted derivatives, such as
alkylperoxybenzoic acids, but also peroxy-a-naphthoic
acid and magnesium monoperphthalate, (b) aliphatic or
substituted aliphatic peroxy acids, such as
peroxylauric acid, peroxystearic acid,
s-phthalimidoperoxycaproic acid [phthaloiminoperoxy-
hexanoic acid (PAP)], o-carboxybenzamidoperoxycaproic
acid, N-nonenylamidoperadipic acid and N-nonenylamido-
persuccinates, and (c) aliphatic and araliphatic
peroxydicarboxylic acids, such as 1,12-diperoxy-
carboxylic acid, 1,9-diperoxyazelaic acid, diperoxy-
sebacic acid, diperoxybrassylic acid, diperoxyphthalic
acids, 2-decyldiperoxybutane-1,4-dioic acid,
N,N-terephthaloyldi(6-aminopercaproic acid).
In order to achieve improved bleaching action in cases
of washing at temperatures of 60°C and below, and in
particular in the case of laundry pretreatment, bleach
activators can be incorporated into the detergent and
cleaner moldings. Bleach activators which can be used
are compounds which, under perhydrolysis conditions,
give aliphatic peroxocarboxylic acids having,
preferably, 1 to 10 carbon atoms, in particular 2 to
4 carbon atoms, and/or optionally substituted
perbenzoic acid. Substances which carry O- and/or
N-aryl groups of said number of carbon atoms and/or
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optionally substituted benzoyl groups are suitable.
Preference is given to polyacylated alkylenediamines,
in particular tetraacetylethylenediamine (TAED),
acylated triazine derivatives, in particular
1,5-diacetyl-2,4-dioxohexahydro-1,3,5-triazine (DADHT),
acylated glycolurils, in particular 1,3,4,6-
tetraacetylglycoluril (TAGU), N-acylimides, in
particular N-nonanoylsuccinimide (NOSI), acylated
phenolsulfonates, in particular n-nonanoyl- or
isononanoyloxybenzenesulfonate (n- or iso-NOBS),
acylated hydroxycarboxylic acids, such as triethyl
O-acetylcitrate (TEOC), carboxylic anhydrides, in
particular phthalic anhydride, isatoic anhydride and/or
succinic anhydride, carboxamides, such as
N-methyldiacetamide, glycolide, acylated polyhydric
alcohols, in particular triacetin, ethylene glycol
diacetate, isopropenyl acetate, 2,5-diacetoxy-
2,5-dihydrofuran and the enol esters known from German
patent applications DE 196 16 693 and DE 196 16 767,
and acetylated sorbitol and mannitol, or mixtures
thereof described in European patent application
EP 0 525 239 (SORMAN), acylated sugar derivatives, in
particular pentaacetylglucose (PAG),
pentaacetylfructose, tetraacetylxylose and
octaacetyllactose, and acetylated, optionally
N-alkylated glucamine or gluconolactone, triazole or
triazole derivatives and/or particulate caprolactams
and/or caprolactam derivatives, preferably N-acylated
lactams, for example N-benzoylcaprolactam and
N-acetylcaprolactam, which are known from International
patent applications WO-A-94/27970, WO-A-94/28102,
WO-A-94/28103, WO-A-95/00626, WO-A-95/14759 and
WO-A-95/17498. The hydrophilically substituted
acylacetals known from German patent application
DE-A-196 16 769 and the acyllactams described in German
patent application DE-A-196 16 770 and International
patent application WO-A-95/14075 are likewise used with
preference. It is also possible to use the combinations
CA 02326758 2000-11-23
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of conventional bleach activators known from German
patent application DE-A-44 43 177. Nitrile derivatives,
such as cyanopyridines, nitrile quats, e.g.
N-alkylammoniumacetonitriles, and/or cyanamide
derivatives can also be used. Preferred bleach
activators are sodium 4-(octanoyloxy)benzenesulfonate,
n-nonanoyl or isononanoyloxybenzenesulfonate (n- or
iso-NOBS), undecenoyloxybenzenesulfonate (UDOBS),
sodium dodecanoyloxybenzenesulfonate (DOBS),
decanoyloxybenzoic acid (DOBA, OBC 10) and/or
dodecanoyloxybenzenesulfonate (OBS 12), and
N-methylmorpholiniumacetonitrile (MMA). Such bleach
activators can be present in the customary quantitative
range from 0.01 to 20% by weight, preferably in amounts
from 0.1 to 15% by weight, in particular 1% by weight
to 10% by weight, based on the total composition.
In addition to the conventional bleach activators or
instead of them, it is also possible for so-called
bleach catalysts to be present. These substances are
bleaching-enhancing transition metal salts or
transition metal complexes, such as, for example, Mn,
Fe, Co, Ru or Mo salene complexes or carbonyl
complexes. Mn, Fe, Co, Ru, Mo, Ti, V and Cu complexes
containing N-containing tripod ligands, and Co, Fe, Cu
and Ru ammine complexes are also suitable as bleach
catalysts, preference being given to using those
compounds described in DE 197 09 284 A1.
The content of bleaches in the compositions can be 1 to
40% by weight and in particular 10 to 20% by weight,
perborate monohydrate or percarbonate being used
advantageously.
The compositions according to the invention generally
comprise one or more builders, in particular zeolites,
silicates, carbonates, organic cobuilders and - where
no ecological grounds oppose their use - also
CA 02326758 2000-11-23
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phosphates. The latter are the preferred builders in
particular in detergent tablets for machine
dishwashing.
Suitable crystalline, layered sodium silicates have the
general formula NaMSiXOzx+1 ~ H2~, where M is sodium or
hydrogen, x is a number from 1.9 to 4, and y is a
number from 0 to 20, and preferred values for x are 2,
3 or 4. Preferred crystalline phyllosilicates of the
given formula are those in which M is sodium and x
assumes the values 2 or 3. In particular, both (3- and
also 8-sodium disilicates Na2SizO5~yHz0 are preferred.
It is also possible to use amorphous sodium silicates
having an Na20:Si02 modulus of from 1:2 to 1:3.3,
preferably from 1:2 to 1:2.8 and in particular from 1:2
to 1:2.6, which have delayed dissolution and secondary
detergent properties. The dissolution delay relative to
conventional amorphous sodium silicates can have been
induced by various means, for example by surface
treatment, compounding, compaction/compression or by
overdrying. Within the scope of this invention, the
term "amorphous" also includes "X-ray amorphous". This
means that in X-ray diffraction experiments the
silicates do not give the sharp X-ray reflections
typical of crystalline substances, but instead, at
best, one or more maxima of the scattered X-rays having
a breadth of several degree units of the diffraction
angle. However, particularly good builder properties
will very likely result if in electron diffraction
experiments the silicate particles give poorly defined
or even sharp diffraction maxima. This is to be
interpreted to the effect that the products have
microcrystalline regions with a size from 10 to a few
hundred nm, preference being given to values up to at
most 50 mm and in particular up to at most 20 nm.
Particular preference is given to compressed/compacted
CA 02326758 2000-11-23
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amorphous silicates, compounded amorphous silicates and
overdried X-ray amorphous silicates.
The finely crystalline, synthetic zeolite containing
bonded water used is preferably zeolite A and/or P. As
zeolite P, zeolite MAP° (commercial product from
Crosfield) is particularly preferred. However,
zeolite X, and mixtures of A, X and/or P are also
suitable. A product which is commercially available and
can be used with preference within the scope of the
present invention is, for example, also a co-
crystallizate of zeolite X and zeolite A (approximately
80% by weight of zeolite X), which is sold by CONDEA
Augusta S.p.A. under the trade name VEGOBOND AX° and
can be described by the formula
nNa20~ (1-n)K20'A12O3~ (2 - 2.5)Si02~ (3.5 - 5.5)H20
Suitable zeolites have an average particle size of less
than 10 ~m (volume distribution; measurement method:
Coulter counter) and preferably contain 18 to 22% by
weight, in particular 20 to 22% by weight, of bonded
water.
A use of the generally known phosphates as builder
substances is of course also possible, provided such a
use is not to be avoided for ecological reasons. Among
the large number of commercially available phosphates,
the alkali metal phosphates are of the greatest
significance in the detergents and cleaners industry,
especially pentasodium or pentapotassium triphosphate
(sodium or potassium tripolyphosphate).
Here, alkali metal phosphates is the collective term
for the alkali metal (in particular sodium and
potassium) salts of various phosphoric acids, it being
possible to differentiate between metaphosphoric acids
(HP03) n and orthophosphoric acid H3P04, as well as
CA 02326758 2000-11-23
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higher molecular weight representatives. The phosphates
combine several advantages: they act as alkali
carriers, prevent lime deposits on machine parts and
lime incrustations in fabrics and moreover contribute
to the cleaning performance.
Sodium dihydrogenphosphate, NaH2P04, exists as dehydrate
(density 1.91 gcm-3, melting point 60°) and as
monohydrate (density 2.04 gcm-3). Both salts are white
powders which are very readily soluble in water and
which lose their water of crystallization upon heating
and at 200°C convert to the weakly acidic diphosphate
(disodium hydrogendiphosphate, Na2H2P20~), at a higher
temperature into sodium trimetaphosphate (Na3P309) and
Maddrell's salt (see below). NaHzP04 is acidic; it forms
when phosphoric acid is adjusted to a pH of 4.5 using
sodium hydroxide solution and the suspension is
sprayed. Potassium dihydrogenphosphate (primary or
monobasic potassium phosphate, potassium biphosphate,
KDP) , KHzP04, is a white salt of density 2 .33 gcm-3, has
a melting point of 253° [decomposition with the
formation of potassium polyphosphate (KP03)X] and is
readily soluble in water.
Disodium hydrogenphosphate (secondary sodium phos-
phate), Na2HP04, is a colorless crystalline salt which
is very readily soluble in water. It exists in
anhydrous form and with 2 mol of water (density
2.066 gcm-3, water loss at 95°), 7 mol of water (density
1.68 gcm-3, melting point 48° with loss of 5 H20) and
12 mol of water (density 1.52 gcm-3, melting point 35°
with loss of 5 H20), becomes anhydrous at 100° and upon
more vigorous heating converts to the diphosphate
Na4Pz0~. Disodium hydrogenphosphate is prepared by
neutralizing phosphoric acid with soda solution using
phenolphthalein as indicator. Dipotassium hydrogen-
phosphate (secondary or dibasic potassium phosphate),
CA 02326758 2000-11-23
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K2HP04, is an amorphous, white salt which is readily
soluble in water.
Trisodium phosphate, tertiary sodium phosphate, Na3P04,
are colorless crystals which in the form of the
dodecahydrate have a density of 1.62 gcm-3 and a melting
point of 73-76°C (decomposition), in the form of the
decahydrate (corresponding to 19-20% of Pz05) have a
melting point of 100°C and in anhydrous form
(corresponding to 39-40% of P205) have a density of
2.536 gcm-3. Trisodium phosphate is readily soluble in
water with an alkaline reaction and is prepared by
evaporating a solution of exactly 1 mol of disodium
phosphate and 1 mol of NaOH. Tripotassium phosphate
(tertiary or tribasic potassium phosphate) , K3P04, is a
white, deliquescent granular powder of density
2.56 gcm-3, has a melting point of 1340° and is readily
soluble in water with an alkaline reaction. It is
produced, for example, during the heating of Thomas
slag with carbon and potassium sulfate. Despite the
higher price, the more readily soluble, and therefore
highly effective, potassium phosphates are often
preferred over corresponding sodium compounds in the
detergents industry.
Tetrasodium diphosphate (sodium pyrophosphate), Na4P20-,,
exists in anhydrous form (density 2.534 gcm-3, melting
point 988°, also 880° given) and as decahydrate
(density 1.815-1.836 gcm-3, melting point 94° with loss
of water). Both substances are colorless crystals which
dissolve in water with an alkaline reaction. Na4P20~ is
formed during the heating of disodium phosphate to
> 200° or by reacting phosphoric acid with soda in a
stoichiometric ratio and dewatering the solution by
spraying. The decahydrate complexes heavy metal salts
and hardness constituents and thus reduces the hardness
of the water. Potassium diphosphate (potassium pyro-
phosphate) , K4P20-,, exists in the form of the trihydrate
CA 02326758 2000-11-23
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and is a colorless, hygroscopic powder having a density
of 2.33 gcm-3, which is soluble in water, the pH of the
1% strength solution at 25° being 10.4.
By condensing NaH2P04 or KHZPO4, higher molecular weight
sodium and potassium phosphates are formed, amongst
which cyclic representatives, the sodium or potassium
metaphosphates, and chain-shaped types, the sodium or
potassium polyphosphates, can be differentiated.
Particularly for the latter, a large number of names
are in use: melt or thermal phosphates, Graham's salt,
Kurrol's and Maddrell's salt. All higher sodium and
potassium phosphates are commonly referred to as
condensed phosphates.
The industrially important pentasodium triphosphate,
Na5P301o (sodium tripolyphosphate) , is a nonhygroscopic,
white, water-soluble salt which is anhydrous or
crystallizes with 6 H20 and is of the general formula
Na0- [P (O) (ONa) -O] n-Na where n - 3 . In 100 g of water,
about 17 g of the salt which is free of water of
crystallization dissolve at room temperature, about
20 g dissolve at 60°, and about 32 g dissolve at 100°;
if the solution is heated at 100° for two hours, about
8% of orthophosphate and 15% of diphosphate form as a
result of hydrolysis. In the preparation of pentasodium
triphosphate, phosphoric acid is reacted with soda
solution or sodium hydroxide solution in a
stoichiometric ratio, and the solution is dewatered by
spraying. Similarly to Graham's salt and sodium
diphosphate, pentasodium triphosphate dissolves many
insoluble metal compounds (including lime soaps etc.).
Pentapotassium triphosphate, KSP301o (potassium tripoly-
phosphate), is available commercially, for example, in
the form of a 50% strength by weight solution (> 23% of
P205, 25% of K20). The potassium polyphosphates are used
widely in the detergents and cleaners industry. In
addition, sodium potassium tripolyphosphates also exist
CA 02326758 2000-11-23
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which can likewise be used within the scope of the
present invention. These arise, for example, when
sodium trimetaphosphate is hydrolyzed with KOH:
(NaP03) 3 + 2 KOH ~ Na3K2P301o + H20
According to the invention, these can be used exactly
as sodium tripolyphosphate, potassium tripolyphosphate
or mixtures of the two; mixtures of sodium tripoly-
phosphate and sodium potassium tripolyphosphate or
mixtures of potassium tripolyphosphate and sodium
potassium tripolyphosphate or mixtures of sodium
tripolyphosphate and potassium tripolyphosphate and
sodium potassium tripolyphosphate can also be used
according to the invention.
Organic cobuilders which can be used in the detergent
and cleaner moldings according to the invention are, in
particular, polycarboxylates/polycarboxylic acids,
polymeric polycarboxylates, aspartic acid, polyacetals,
dextrins, further organic cobuilders (see below), and
phosphonates. These classes of substance are described
below.
Organic builder substances which can be used are, for
example, the polycarboxylic acids usable in the form of
their sodium salts, the term polycarboxylic acids
meaning those carboxylic acids which carry more than
one acid function. Examples of these are citric acid,
adipic acid, succinic acid, glutaric acid, malic acid,
tartaric acid, malefic acid, fumaric acid, sugar acids,
aminocarboxylic acids, nitrilotriacetic acid (NTA),
provided such a use is not objectionable on ecological
grounds, 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.
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The acids per se may also be used. In addition to their
builder action, the acids typically also have the
property of an acidifying component and thus also serve
to establish a lower and milder pH of detergents or
cleaners. In this connection, particular mention is
made of citric acid, succinic acid, glutaric acid,
adipic acid, gluconic acid and any mixtures thereof.
Also suitable as builders are polymeric poly-
carboxylates; these are, for example, the alkali metal
salts of polyacrylic acid or of polymethacrylic acid,
for example those having a relative molecular mass of
from 500 to 70 000 g/mol.
The molar masses given for polymeric polycarboxylates
are, for the purposes of this specification, weight-
average molar masses, MW, of the respective acid form,
determined fundamentally by means of gel permeation
chromatography (GPC) using a W detector. The measure-
ment was made against an external polyacrylic acid
standard which, owing to its structural similarity to
the polymers under investigation, provides realistic
molecular weight values. These figures differ
considerably from the molecular weight values obtained
using polystyrenesulfonic acids as the standard. The
molar masses measured against polystyrenesulfonic acids
are usually considerably higher than the molar masses
given in this specification.
Suitable polymers are, in particular, polyacrylates
which preferably have a molecular mass of from 2000 to
20 000 g/mol. Owing to their superior solubility,
preference in this group may be given in turn to the
short-chain polyacrylates which have molar masses of
from 2000 to 10 000 g/mol and particularly preferably
from 3000 to 5000 g/mol.
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Also suitable are copolymeric polycarboxylates, in
particular those of acrylic acid with methacrylic acid
and of acrylic acid or methacrylic acid with malefic
acid. Copolymers which have proven to be particularly
suitable are those of acrylic acid with malefic acid
which contain from 50 to 90% by weight of acrylic acid
and 50 to 10% by weight of malefic acid. Their relative
molecular mass, based on free acids, is generally 2000
to 70 000 g/mol, preferably 20 000 to 50 000 g/mol and
in particular 30 000 to 40 000 g/mol.
The (co)polymeric polycarboxylates can either be used
as powders or as aqueous solutions. The (co)polymeric
polycarboxylate content of the compositions can be from
0.5 to 20% by weight, in particular 3 to 10% by weight.
To improve the solubility in water, the polymers can
also contain allylsulfonic acids, such as, for example,
allyloxybenzenesulfonic acid and methallylsulfonic
acid, as monomer.
Particular preference is also given to biodegradable
polymers of more than two different monomer units, for
example those which contain, as monomers, salts of
acrylic acid and of malefic acid, and vinyl alcohol or
vinyl alcohol derivatives, or those which contain, as
monomers, salts of acrylic acid and of 2-alkylallyl-
sulfonic acid, and sugar derivatives.
Further preferred copolymers are those which preferably
have, as monomers, acrolein and acrylic acid/acrylic
acid salts or acrolein and vinyl acetate.
Further preferred builder substances which may be
mentioned are also polymeric aminodicarboxylic acids,
their salts or their precursor substances. Particular
preference is given to polyaspartic acids or salts and
derivatives thereof.
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Further suitable builder substances are polyacetals,
which can be obtained by reacting dialdehydes with
polyolcarboxylic acids which have 5 to 7 carbon atoms
and at least 3 hydroxyl groups. Preferred polyacetals
are obtained from dialdehydes such as glyoxal,
glutaraldehyde, terephthalaldehyde and mixtures thereof
and from polyolcarboxylic acids such as gluconic acid
and/or glucoheptonic acid.
Further suitable organic builder substances are
dextrins, examples being oligomers or polymers of
carbohydrates, which can be obtained by partial
hydrolysis of starches. The hydrolysis can be carried
out by customary processes, for example acid-catalyzed
or enzyme-catalyzed processes. The hydrolysis products
preferably have average molar masses in the range from
400 to 500 000 g/mol. Preference is given here to a
polysaccharide having a dextrose equivalent (DE) in the
range from 0.5 to 40, in particular from 2 to 30, where
DE is a common measure of the reducing effect of a
polysaccharide compared with dextrose, which has a DE
of 100. It is possible to use maltodextrins having a DE
between 3 and 20 and dried glucose syrups having a DE
between 20 and 37, and also so-called yellow dextrins
and white dextrins with higher molar masses in the
range from 2000 to 30 000 g/mol.
The oxidized derivatives of such dextrins are their
reaction products with oxidizing agents which are able
to oxidize at least one alcohol function of the
saccharide ring to the carboxylic acid function. A
product oxidized on the C6 of the saccharide ring may
be particularly advantageous.
Oxydisuccinates and other derivatives of disuccinates,
preferably ethylenediamine disuccinate, are also
further suitable cobuilders. Here, ethylenediamine
CA 02326758 2000-11-23
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N,N'-disuccinate (EDDS) is preferably used in the form
of its sodium or magnesium salts. In this connection
further preference is also given to glycerol
disuccinates and glycerol trisuccinates. Suitable use
amounts in zeolite-containing and/or silicate-
containing formulations are 3 to 15°s by weight.
Further organic cobuilders which can be used are, for
example, acetylated hydroxycarboxylic acids or salts
thereof, which may also be present in lactone form and
which contain at least 4 carbon atoms and at least one
hydroxyl group and at most two acid groups.
A further class of substance having cobuilder
properties is the phosphonates. These are, in
particular, hydroxyalkane- and aminoalkanephosphonates.
Among the hydroxyalkanephosphonates, 1-hydroxyethane-
1,1-diphosphonate (HEDP) is of particular importance as
a cobuilder. It is preferably used as sodium salt, the
disodium salt being neutral and the tetrasodium salt
being alkaline (pH 9). Suitable aminoalkanephosphonates
are preferably ethylenediaminetetramethylenephosphonate
(EDTMP), diethylenetriaminepentamethylenephosphonate
(DTPMP) and higher homologs thereof. They are
preferably used in the form of the neutral sodium
salts, e.g. as the hexasodium salt of EDTMP or as the
hepta- and octasodium salt of DTPMP. Here, preference
is given to using HEDP as builder from the class of
phosphonates. In addition, the aminoalkanephosphonates
have a marked heavy-metal-binding capacity.
Accordingly, particularly if the compositions also
contain bleaches, it may be preferable to use
aminoalkanephosphonates, in particular DTPMP, or
mixtures of said phosphonates.
Moreover, all compounds which are able to form
complexes with alkaline earth metal ions can be used as
cobuilders.
CA 02326758 2000-11-23
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In a preferred embodiment, the detergents and cleaners
according to the invention are liquid to gelatinous
compositions.
Solvents which can be used in the liquid to gelatinous
compositions are, for example, from the group of
monohydric or polyhydric alcohols, alkanolamines or
glycol ethers, provided they are miscible with water in
the given concentration range. Preferably, the solvents
are chosen from ethanol, n- or i-propanol, butanols,
ethylene glycol methyl ether, ethylene glycol ethyl
ether, ethylene glycol propyl ether, ethylene glycol
mono-n-butyl ether, diethylene glycol methyl ether,
diethylene glycol ethyl ether, propylene glycol methyl,
ethyl or propyl ether, dipropylene glycol monomethyl or
monoethyl ether, diisopropylene glycol monomethyl or
monoethyl ether, methoxy-, ethoxy- or butoxytriglycol,
1-butoxyethoxy-2-propanol, 3-methyl-3-methoxybutanol,
propylene glycol t-butyl ether, and mixtures of these
solvents. Solvents can be used in the liquid to
gelatinous detergents according to the invention in
amounts between 0.1 and 20% by weight, but preferably
below 15s by weight and in particular below 10% by
weight.
To adjust the viscosity, one or more thickeners or
thickening systems can be added to the composition
according to the invention. The viscosity of the
compositions according to the invention can be measured
using customary standard methods (for example
Brookfield viscometer RVD-VII at 20 rpm and 20°C,
spindle 3) and is preferably in the range from 100 to
5000 mPas. Preferred compositions have viscosities of
from 200 to 4000 mPas, values between 400 and 2000 mPas
being particularly preferred.
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Suitable thickeners are inorganic or polymeric organic
compounds. These mostly organic high molecular weight
substances, which are also called swelling) agents, in
most cases soak up the liquids and swell in the
process, converting ultimately into viscous true or
colloidal solutions.
Inorganic thickeners include, for example, polysilicic
acids, clay minerals, such as montmorillonites,
zeolites, silicas and bentonites.
The organic thickeners are from the groups of natural
polymers, modified natural polymers or completely
synthetic polymers.
Natural polymers which are used as thickeners are, for
example, agar agar, carageen, tragacanth, gum arabic,
alginates, pectins, polyoses, guar flour, carob seed
grain, starch, dextrins, gelatins and casein.
Modified natural substances are primarily from the
group of modified starches and celluloses. Examples
which may be mentioned here are carboxymethylcellulose
and other cellulose ethers, hydroxyethylcellulose and
hydroxypropylcellulose, and carob flour ether.
A large group of thickeners which are used widely in
very different fields of application are the completely
synthetic polymers, such as polyacrylic and poly-
methacrylic compounds, vinyl polymers, polycarboxylic
acids, polyethers, polyimines, polyamides and poly-
urethanes.
The thickeners may be present in an amount up to 5% by
weight, preferably from 0.05 to 2% by weight, and
particularly preferably from 0.1 to 1.5% by weight,
based on the finished composition.
CA 02326758 2000-11-23
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The detergent or cleaner according to the invention can
comprise, as further customary ingredients, in
particular sequestering agents, electrolytes, pH
regulators, phosphonates, enzymes and further
auxiliaries, such as optical brighteners, anti-
redeposition agents, color-transfer inhibitors, foam
regulators, additional bleach activators, dyes and
fragrances.
For use in machine washing processes it may be
advantageous to add customary foam inhibitors to the
compositions. Suitable foam inhibitors are, for
example, soaps of natural or synthetic origin which
have a high proportion of C18-Ca4-fatty acids. Suitable
nonsurfactant foam inhibitors are, for example,
organopolysiloxanes and mixtures thereof with
microfine, optionally silanized silica, and paraffin,
waxes, microcrystalline waxes and mixtures thereof with
silanized silica or bistearylethylenediamide. It is
also advantageous to use mixtures of different foam
inhibitors, e.g. those of silicones, paraffins or
waxes. The foam inhibitors, in particular silicone- or
paraffin-containing foam inhibitors, are preferably
attached to a granular, water-soluble or water-
dispersible carrier substance. Particular preference is
given here to mixtures of paraffins and bistearyl-
ethylenediamides.
As salts of polyphosphonic acids, preference is given
to using the neutral sodium salts of, for example,
1-hydroxyethane-1,1-diphosphonate, diethylenetriamine-
pentamethylenephosphonate or ethylenediaminetetra-
methylenephosphonate, which can be used in amounts of
from 0.1 to 1.5% by weight.
The compositions according to the invention can
comprise, as optical brighteners, derivatives of
diaminostilbenedisulfonic acid or alkali metal salts
CA 02326758 2000-11-23
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thereof. Suitable are e.g. salts of 4,4'-bis(2-anilino-
4-morpholino-1,3,5-triazinyl-6-amino)stilbene-2,2'-
disulfonic acid or similarly constructed compounds
which carry a diethanolamino group, a methylamino
group, an anilino group or a 2-methoxyethylamino group
instead of the morpholino group. In addition,
brighteners of the substituted diphenylstyryl type may
be present, e.g. the alkali metal salts of
4,4'-bis(2-sulfostyryl)diphenyl, 4,4'-bis(4-chloro-
3-sulfostyryl)diphenyl or 4-(4-chlorostyryl)-
4'-(2-sulfostyryl)diphenyl. Mixtures of the above-
mentioned brighteners can also be used.
If the composition according to the invention is used
as a so-called liquid to gelatinous detergent, it
preferably comprises from 0 to 20% by weight of anionic
surfactants, 40 to 80% by weight of nonionic
surfactants, 2 to 25% by weight of builder materials, 0
to 20% by weight of bleaches, 0 to 20% by weight of
bleach activators, 0 to 5% by weight of enzymes,
fragrances and further ingredients.
CA 02326758 2000-11-23
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Example
For the preparation of microemulsions, starch was
dissolved in water. After the starch had swelled, a
protease solution with an activity of 800 000 PU/g was
added. The enzyme solution was then finely dispersed
within the starch solution using a dispersion apparatus
(Dispax~ from IKA) .
Table 1
Micro- Micro- Untreated
emulsion emulsion enzyme
1 2
concentrate
Enzyme Protease Protease Protease
Composition (%):
Narlex~ ST 2 starch 44 36 0
(Manufacturer: National
Starch)
Water from starch solution30 24 0
Protease concentrate 26 40 100
Viscosity (mPas) 4300 2900 100
Use amount (%) in the
Persil Kraftgel liquid 0.4 0.26 0.15
detergent
(Manufacturer: Henkel
KgaA)
Protease concentrate 0.10 0.10 0.15
amount (%) in the liquid
detergent
The enzyme stability in the liquid detergent was tested
in a test under intensified conditions (temperature
60°C) in order to simulate realistic aging.
As Table 2 shows, both microemulsions displayed
significant stability advantages over the untreated
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protease concentrate. For microemulsion 1, no decrease
at all in the enzyme activity was detected. For
microemulsion 2, the activity loss was less than 10%.
By contrast, the untreated enzyme sample had an
activity loss of 25-30%.
It was therefore found that the microencapsulated
enzymes obtained according to the invention have good
stability. In particular, no delayed protein
precipitations were observed, as is often the case with
the enzyme preparations obtained from the prior art.
The product obtained also had a pale beige color,
meaning that no special further decoloration is
required.
The enzyme concentrates are usually mixed with a
polydiol in order to improve the storage stability.
However, such enzyme solutions with polydiol are often
black or brown in color, necessitating decoloration
prior to further processing in detergents and cleaners.
Table 2
t = 0 60 min 90 min
Microemulsion 1 100 100 100
Microemulsion 2 100 96 91
Microemulsion 3 100 72 70
