Note: Descriptions are shown in the official language in which they were submitted.
~L3~37~
- 1 - C.3~44
DETERGENT COMPOSI~ION
.
This invention relates to deter~ent compositions for
S washing fabrics, in particular to detergent compositions
which are capable of cleaning and softening fabrics from
the s,Ime wash liquo~.
Detergent compositions for simultaneously cleaning
and softening fabrics are known in the art.
Conventionally such compositions contain, as a detergent
active material, an anionic surfactant to clean the
fabrics and a cationic fabric softening agent. However,
there is a tendency for the anionic and cationic
components of such compositions to react with each other,
either in the product i~self or in the wash liquor, with
the result that the efficiency of the cationic softening
agent is significantly reduced.
Various solutions to this problem have been
proposed~ One such proposal, as described in United
States patent specification 3 936 537 (BASKERVILLE et al
assigned to THE PROCTER~& GAMBLE COMPANY) is to combine
.
- :
- 2 - C.30~4
the cationic components in a separate particle with a
dispersion inhibitor, such as a long chain alkanol, with
the object of reducing the interaction with the anionic
surfactant in the wash liquor.
An alternative proposal is to avoid the use of
anionic surfactants, by for example using nonionic
surfactants as described in British Patent Specification
GB 1 079 388 tGENERAL FOODS CORPORATION).
A further series of proposals relate to the us~ of
alternative fabric softening agents in place of the
cationic material. One such example is to use
cellulolytic enzymes ie cellulase, as a harshness-
reducing agent, as disclosed in British Patent
Specification GB 1 368 599 (UNILEVER). Other enzymes,
such as proteolytic enzymes like Alcalase, do not provide
softening benefits. A further example is to use various
clay materials as disclosed in United States patent
specification US 4 062 647 ~STORM et al assigned to THE
PROCTER & GAMBLE COMPANY) .
To date, none of these various proposals bythemselves, have lead to commercially successful products.
It is thought that cellulase achieves its anti~
harshening effect on eg cotton, by cleaving and thereby
assisting the removal of the cellulosic fibrils which form
on the fabric fibres in the normal washing process, the
bonding of these fibrils to each other and the cotton
fibres themselves being responsible for introducing a
degree of rigidity, that is harshening, to the fabric
surface. On the other hand it is believed that clay
materials achieve their softening benefit by coating the
fibres and fibrils with a layer o~ lubricating material
thereby lowering the friction between fibrils and
- 3 - C.3044
fibrils/fibres reducing the tendency of the fibril~ ~o
bond together. One would expect therefor2 that where a
composition contains cellulase as a fabric softening
agent, there is nothing to be gained from the additional
inclusion of clay materials, the fibrils having been
removed following cellulase action. Looking at *he
matter in another manner, one would expect that where a
composition contains a clay material as a softening agent,
there is no~hing to be yained rom the additional
inclusion of ~ellulase, the clay coating on the fibrils
effectively screening the fibrils from attack by the
callulase, which is known to be selective towards
cellulosic matexial~ and not in any way to attack clay
materials~
For this reason one would expect that in
compo~itions which contain both cellulase and clay
materials, these softening agents would appear to mutually
inhibit one another and we believe it i3 for this reason
that compo~itions containing both cellulase and clay
materials as softening agents have not previously been
proposed.
We have now surprisingly discovered however ~hat
this mutual inhibition does not occur in practice and that
therefore fabric washing compositions which contain both
cellulase and clay materials aq softening agents provide
qurprisingly good softening results.
Thus, according to the invention, there i5 provided
a detergent composition for cleaning and softening fabrics
comprising:
.
( i) 5 to 50% of a detergent active material;
_ 4 _ C.304~
( ii) 1.5 to 35~ of a fabric softening clay material, and
(iii) 0.1 to 10~ of cellulase.
We are aware of British patent specification Nos.
2 094 826, 2 095 275 and 2 124 244 fKA0 SOAP) which
disclose detergent compositions which contain specific
types of cellulase to provide improved detergency. In
these specifications clay, of unspecified type, is
mentioned as an ingredient for inhibiting caking of the
compo6itions.
The compositions according to the invention
necessarily contain a detergent active material, otherwise
referred to herein simply as a detergent compound. The
detergent compounds may be selected from anionic,
nonionic, zwitterionic and amphoteric synthetic detergent
active materials. ~any suitable detergent compounds are
commercially available and are fully described in the
literature, for example in "Surface Active Agents and
Detergents~, Volumes I and II, by Schwartz, Perry and
Berch.
The preferred detergent compounds which can be used
are synthetic anionic and nonionic compounds. The former
are usually water-soluble alkali metal salts of organic
sulphates and sulphonates having alkyl radicals containing
from about 8 to about 22 carbon atoms, the term alkyl
being used to include the alkyl portion of higher acyl
radicals. Examples of suitable synthetic anionic
detergent compound~ are sodium and potassium alkyl
sulphate~, especially those obtained by sulphating higher
tC8-C18 ) alcohols produced for example from tallow or
coconut oil, sodium and potas~ium alkyl (Cg-C20) benzene
sulphonates, particularly sodium linear secondary alkyl
(Clo-C15) benzene sulphonates; sodium alkyl glyceryl ether
:
,
.
D8~
- 5 - C.30~4
sulphates, especially those ethers of the higher alcohols
derived from tallow or coconut oil and synthetic alcohols
derived from petroleum; sodium coconut oil fatty
monogl~ceride sulphates and sulphonates; sodium and
potassium salts of sulphuric acid esters of higher
(C8-C18) fatty alcohol-alkylene oxide, particularly
ethylene oxide, reaction products; the reaction products
of fatty acids such as coconut fatty acids esteri~ied with
isethionic acid and neutralised with sodium hydroxide;
sodium and potassium salts of fatty acid amides of methyl
taurine; alkane monosulphonates such as those derived by
reacting alpha-olefins (C8-C20) with sodium bisulphite and
those derived from reacting paraffins with S02 and C12 and
then hydrolysing with a base to produce a random
sulphonate; and olefin sulphonates, which term is used to
describe the material made by reacting olefins,
particularly C10-C20 alpha-olefins, with S03 and then
neutralising and hydrolysing the reaction product. The
preferred anionic detergent compounds are sodium (Cll-C15)
alkyl benzene sulphonates and sodium (C16-C18) alkyl
sulphates.
Suitable nonionic detergent compounds which may be
used include in particular the reaction products of
compounds having a hydrophobic group and a reactive
hydrogen atom, for example aliphatic alcohols, acids,
amides or alkyl phenols with al~ylene oxides, especially
ethylene oxide either alone or with propylene oxide.
Specific nonionic detergent compounds are alkyl (C6-C22)
phenols-ethylene oxide condensates, generally 5 to 25 EO,
ie 5 to 25 units of ethylene oxide per molecule, the
condensation products of aliphatic (C8-C18) primary or
secondary linear or branched alcohols with ethylene oxide,
generally 5 to 40 EO, and products made by condensation of
ethylene oxide with the reaction products of propylene
oxide and ethylenediamine. Other so-called nonionic
3~L
- 6 - C.3044
detergent compounds include long chain tertiary amine
oxides, long chain tertiary phosphine oxides and dialkyl
sulphoxides.
Mixtures of detergent compounds, for example mixed
anionic or mixed anionic and nonionic compounds may be
used in the detergent compositions, particularly in the
latter case to provide controlled low sudsing properties.
This is beneficial for compositions intended for use in
suds-intolerant automatic washing machines.
Amounts of amphoteric or zwitterionic detergent
compounds can also be used in the compositions of the
invention but this i5 not normally desired due to their
relatively high cost. If any amphoteric or zwitterionic
detergent compounds are used it is generally in small
amounts in compositions based on the much more commonly
used synthetic anionic and/or nonionic detergent
compounds.
The effective amount of the detergent active
compound or compounds used in the composition of the
present invention is generally in the range of from 2 to
50~, preferably from 5 to 40~ by weight, most preferably
not more than 30% by weight of the composition.
A second essential component of the compositions of
the present invention is a fabric softening clay material.
This clay material should be a phyllosilicate clay with a
2:1 layer structure, which definition includes
pyrophyllite clays, smectite or montmorillonite clays,
saponites, vermiculites and micas. Clay materials which
have been found to be unsuitable for fabric softening
purposes include chlorites and kaolinites. Other
aluminosilicate materials which do not have a layer
structure, such as zeolites are also unsuitable as fabric
;3 s)~
- 7 - C.3044
softening clay materials. Particularly suitable clay
materials are the smectite clays described in detail in
United States Patent Specification US 3 959 155 (MONTGOMERY
et al assigned to THE PROCTER & GAMBLE COMPANY), especially
smectite clays such as described in United States Patent
Specification US 3 936 537 (BASKE~VILLE - referred to
above). Other disclosures of suitable clay materials for
fabric softening purposes include European patent
specification EP 26528-A (PROCTER & GAMBLE LIMITED).
The most preferred clay fabric softening materials
include those materials of bentonitic origin, bentonites
being primarily montmorillonite type clays together with
various impurities, the level and nature of which depends
on the source of the clay material.
The level of fabric softening clay material in the
compositions of the invention should be sufficient to
provide the fabrics with a softening benefit. A preferred
level is 1.5~ to 35% by weight of the composition, most
preferably from 4% to 15%, these percentages referring to
the level of the clay mineral er se. Levels of clay raw
material higher than this may be necessary when the raw
material is derived from a particularly impure source.
A third essential component of the compositions of
the invention is the cellulase.
The cellulase in the present invention may be any
bacterial or fungal cellulase having a pH optimum of
between 5 and 11.5. It is however preferred to use
cellulases which have optimum activity at alkaline p~
values, such as those described in British Patent
~`
,
- 8 - C.30~4
Specifications GB 2 075 028 A (NOVO INDUSTRIE A/S~,
GB 2 095 275 A (KAO SOAP CO LTD~ and GB 2 094 826 A (KAO
SOAP CO LTD).
Examples of such alkaline cellulases are cellulases
produced by a strain of ~umicola insolens (Humicola grisea
var. thermoidea), particularly the Humicola strain DSM
1800, and cellulases produced by a fungus of Bacillus N or
a cellulase 212-producing fungus belonging to the genus
Aeromonas, and cellulase ex~racted from the hepatopancreas
of a marine mullosc (Dolabella Auricula Solander).
The cellulase added to the composition o~ the
invention may be in the form of a non-dusting granulate,
eg "marumes" or "prill~", or in the form of a liquid in
whi~h the cellulase is provided as a cellulase concentrate
suspended in eg a nonionic surfactant or dissolved in an
aqueous medium, having cellulase activity of at least 250
regular Cx cellulase activity units/gram, measured under
the standard conditions as described in GB 2 075 028 A~
The amount of cellulase in the composition of the
invention will, in general, be from about 0.1 to 10% by
weight in whatever form. In terms of cellulase activity
the use of cellulase in an amount corresponding to from
0.25 to 150 or higher regular Cx units/gram of the
detergent composition is within the preferred scope of the
present invention. A most preferred range of cellulase
activity, however, is from 0.5 to 25 regular Cx units/gram
of the detergent composition.
The compositions of the invention will generally
include a detergency builder to improve the efficiency of
the detergent active, in particular to remove calcium
hardness ions from the water and to provide alkalinity.
The builder material may be selected from precipitating
_ g _ C.3044
builder materials (such as alkali metal carbonates,
bicarbonates, borates, orthophosphates and silicates),
sequestering builder materials (such as alkali metal
pyrophosphates, polyphosphates, amino polyacetates,
phytates, polyphosphonates, aminopolymethylene
phosphonates and polycarboxylates), ion-exchange builder
materials (such as zeolites and amorphous alumino-
silicates), or mixtures of any one or more of these
materials. Preferred examples of builder matPrials
include sodium tripolyphosphate, mix~ures thereof with
sodium orthophosphate, sodium carbonate, mixtures thereof
with calcite as a seed crystal, sodium citrate, zeolite
and the sodium salt of nitrilotriacetic acid.
The level of builder material in the compositions of
the invention may be up to 80% by weight, p,referably from
20~ to 70% by weight and most preferably from 30~ to 60%
by weight.
Apart from the components already mentioned, a
detergent composition of the invention can contain any of
the conventional additives in the amounts in which such
additives are normally employed in fabric washing
detergent compositions. Examples of these additives
include the lather boosters such as alkanolamides,
particularly the monoethanolamides derived from palm
kernel atty acids and coconut fatty acids, lather
depressants, oxygen-releasing bleaching agents such as
sodium perborate and sodium percarbonate, peracid bleach
precursors, chlorine-releasing bleaching agents such as
tricloroisocyanuric acid, inorganic salts such as sodium
sulphate, and, usually present in very minor amounts,
1uorescent agents, perfumes, other enzymes such as
proteases and amylases, qermicides and colourants.
- 10 - C.3044
We have found it particularly beneficial to include
in the compositions of the invention an antistatic agent,
to reduce the level of static on washed fabrics,
especially those fabrics which include synthetic fibres,
S such as nylon.
The antistatic agents useful herein are quaternary
ammonium salts of the formula ~RlR2R3R4N] Y wherein at
least one, but not more than two, of Rl, R2, R3 and R~ is
an organic radical containing a group selected from a
C16-C22 aliphatic radical, or an alkyl phenyl or alkyl
benzyl radical having 10-16 atoms in the alkyl chain, the
remaining group or groups being selected from hydrocarbyl
groups containing from 1 to about 4 carbon atoms, or C2 C4
hydroxy alkyl groups and cyclic structures in which the
nitrogen atom forms part of the ring, and Y is an anion
such as halide, methylsulfate, or ethylsulfate.
In the context of the above definition, the
hydrophobic moiety (ie, the C16-C22 aliphatic, Cl~-C16
alkyl phenyl or alkyl benzyl radical) in the organic
radical Rl may be directly attached to the quaternary
nitrogen atom or may be indirectly attached thereto
through an amide, esters, alkoxy, e~her, or like grouping.
The quaternary ammonium antistatic agents can be
prepared in various ways well known in the art. Many
such materials are commercially available. The
quaternaries are often made from alkyl halide mixtures
corresponding to the mixed alkyl chain lengths in fatty
acids. For example, the "ditallown quaternaries are made
from alkyl halides having mixed C14-C18 chain lengths.
Such mixed di-long chain quaternaries are useful herein
and are preferred from a cost standpoint. Optionally,
the tallow alkyl groups are hydrogenated or "hardened" to
reduce the level of unsaturation and thereby raise the
- 11 - C.3044
melting point and lower the water-solubility of compounds
made therefrom. As used herein "ditallow" is intended to
refer to the above-described ditallowalkyl quaternaries,
either in their hardened or unhardened forms.
The quaternary ammonium antistatic compounds useful
herein include both water-soluble and substantially
water-insoluble materials. Imidazolinium compounds
enumerated in US 3 936 537 (BASKERVILLE - referred to
above) possess appreciable water solubility and are
preferably utilised in the pxesent invention by mixing
with an appropriate type and level of organic dispersion
inhibitor and complexing component to give ultimate
particle solubility in water of less than 50 ppm lParts
per million~ at 25C. Relatively water-soluble
quaternary ammonium antistatic agents may also be of the
nonring variety, such as diisostearyl dimethyl ammonium
chlorides. Exempl~ry quatexnary ammonium imidazolinium
compounds are specifically methyl-l-alkylamidoethyl-2-
alkyl imidazolinium methyl sulfates, specificallyl-methyl-l-[(tallowamido)ethyl]-2-tallowimidazolinium
methyl sulfate. However, the most useful quaternary
ammonium antistatic agents are characterised by relatively
limited solubility in water.
The following are representative examples of
substantially water-insoluble quaternary ammonium
antistatic agents suitable for use in the compositions of
the instan~ invention. Dioctadecyldimethyl ammonium
chloride is an especially preferred quaternary antistatic
agent for use herein by virtue of its high antistatic
activity; ditallow dimethyl ammonium chloride is equally
preferred because of its ready availability and its good
antistatic activity; other useful di-long chain quaternary
compounds are dicetyl dimethyl ammonium chloride;
bis-docosyl dimethyl ammonium chloride; didodecyl dimethyl
.
- 12 - C.3044
ammonium chloride; ditallow dimethyl ammonium bromide;
dioleyoyl dimethyl ammonium hydroxide; ditallow dimethyl
ammonium chloride; ditallow dipropyl ammonium bromide;
ditallow dibutyl ammonium fluoride; cetyldecylmethylethyl
ammonium chloride; bis-[ditallow dimethyl ammonium~
sulfate; and tris [ditallow dimethyl ammonium] phosphate.
The level of cationic antistatic agent should be
sufficien~ to provide an antistatic benefit on synthetic
fabrics. We have found that at least 1.0% by weight,
most preferably at least 1.5% by weight of cationic
antistatic agent is suitable. The compositions of the
invention need not contain more than 10~ by weight,
generally not more than 6% by weight antistatic agent.
The compositions of the invention may also include
organic amines. Suitable amines include primary,
secondary and tertiary amines, such as hydrogenated tallow
alkyl primary amine, secondary coconut methyl amine or
methyl di-hardened tallow alkyl tertiary amine. The
presence of such amines in the composition is known to
enhance the perfume delivery to the fabrics. A suitable
level for the amine in the composi~ion is from 1.0% to
10%, most preferably 1.5% to 6% by weight.
PREPARATION OF THE COMPOSI~ION
The detergent compositions may be prepared in any
way appropriate to their physical form such as by -
dry-mixing the components, co agglomerating them or
dispersing them in a liquid carrier. However, a
preferred physical form is a granule incorporating a
deterg ncy builder material and this is most conveniently
manufactured by spray-drying at least part of the
composition.
' .
'
` ','
.
`` ~ 7~
- 13 - C.304~
The preferred compositions of the invention may be
prepared by making up an aqueous slurry of the
non-heat-sensitive component~, comprising the anionic
and/or nonionic surfactants, the clay-fabric softening
material, the builder and filler salts together with any
soil-suspending agents and optical brighteners, and
spray-drying this slurry. The moisture content of the
slurry is normally in the range of 28% to 35% and its
temperature is conveniently in the range of 70C-95C.
The spray-drying tower inlet temperatures are normally in
the range of 300-360C and the resultant spray-dried
granules have a moisture content of 8-12% by weight. An
optional, but preferred, additional processing step i5 to
cool the dried granules rapidly by means of cool air from
a temperature o 90C to a temperature in the range of
25-35C, in order to facilitate the further processing of
the product. Solid heat-sensitive components, such as
persalts and enzymes, are mixed with the spray-dried
granules. Although ~he cationic antistatic agent, if
2Q any, may be included in the slurry for spray-drying, this
component may degrade under certain processing conditions
and adversely affect product quality. It is therefore
preferred that the antistatic agent if any be liquefied by
melting or solvent dissolution and that this liquid be
sprayed onto the spray-dried granules before or after
other heat-sensitive solids have been dry-mixed with them.
If the antistatic agent is applied as a melt, a liquid
temperature of 5-30C in excess of the melting point can
conveniently be used for the spray-on. When the
antistatic agent is a waxy solid of rather low melting
point, it may be blended with a compatible higher melting
substance so as to ensure that granules sprayed on
therewith are sufficiently crisp, are free-flowing and do
not cake on storage. It is also possible to add the clay
material as a granule, together with the solid
heat-sensitive components to ~he spray-dried granules.
- 1~ - C.30~4
The invention is illustrated by the following non-
limiting examples.
EXAMPLES 1 AND 2
A detergent composition was prepared by spray-drying
the following components:
Alkyl benzene sulphonate 5.5
Ethoxylated alcohol 3.0~
Soap 2.0%
Sodium tripolyphosphate 30.0%
Sodium silicate 5.0%
Sodium sulphate 8.0%
Water and minor ingredients 11.5%
where the percentages quoted are based on the weight of
the final product. To this spray-dried base powder was
added 21.0~ of sodium perborate tetrahydrate and 14%
sodium sulphate. This composition was used as a control.
Further compositions were prepared which included various
amounts of clay and cellulase as set out below. These
components were added to the spray dried base powder
granules and the level of post-dosed sodium sulphate in
the base powder was reduced accordingly.
Example No: Control A B C _ 1 2
Cellulase - 0.55%* 3.3%** - 0.55%* 3.3%**
Clay - - - 10% 10% 10~
* Cellulase added to give 10 Cx units/l in the wash
(pH 9.3)~
** Cellulase added to give 60 Cx units/l in the wash
(pH 9.3).
:
.
. , ' ' .
,
` ' , "' .
- 15 - C.3044
These compositions were then used to wash pre-
harshened terry towelling monitors. The product dosage
was 5 g/l, the water hardness was 8GH equivalent to
about 1.36xlO 3molar free calcium ions and the pH of the
wash liquor was approximately 9.~ IELE (Trade Mark)
automatic washing machine was used on a 25C to 40C heat
up cycle, heating up at 2C/min. The wash time was 35
minutes. After washing the monitors were rinsed 3 times
in tap water. After 5 washes the monitors were
line-dried and then assessed for softness using a
laboratory fabric softness measuring device. ~he results
were as set out in the following Table, the softness of
the monitors washed once in the control formulation being
taken as 100%.
Example No % softness after 5 washes
Control (after 1 wash) 100
Control (after 5 washes3 103
A 108
B 122
C 111
1 118
2 127
A comparison of the results obtained from all
compositions relative to the control shows that both
cellulase and clay improve the measured softening. A
comparison of the results obtained from compositions A, C
and Example 1 shows that the use of clay and cellulase
together gives a softening benefit which is greater than
the use of either softening component alone. A similar
conclusion can be drawn from a comparison of compositions
B, C and Example 2.
- 16 - C.30~4
The cellulase used in these compositions was a
granulated ~umicola insolens cellulase SP 227 ex NOVO
having an activity at pH 9,3 of 365 Cx units/gram. The
clay used in these compositions was White Bentonite from
~urkey, available from Steetley Minerals ~imited, England
which consists of about 95% clay mineral and has a cation
exchange capacity of between 90 and 100 meqllOO g.
Similar results are obtained when additionally 4~ by
weight of diharde~ed tallow dimethyl ammonium chloride
~AROSURF TA 100 - Trade Mark) are included as an
antistatic agent, and antistatic test~ on synthetic
fabrics show a significant benefit over those compositions
where no antistatic agent is present. ~lso, similar
benefits for the combination of clay and cellulase occur
when the phosphate containing base referred to above is
replaced with a base containing zeolite and sodium
carbonate but no phosphate.
EXAMPLES 3 AND 4
Using the same spray-dried base powder used in
Examples 1 and 2, compositions were prepared having the
following formulations (% by weight).
.
~L3~3~
- 17 - C.3044
Example No: Control D E 3 F ~ 4
Base powder65 65 65 65 65 65 65
Clay - l - 10 10 10
Clay - 2 ~ 10 10 10
Cellulase - - - 1.0* - - 1.0*
Alcalase - - 0.21**- - 0~21**-
Sodium
perborate 21 2121 21 21 21 21
Sodium
sulphate ---------- balance to 100% ~
* Cellulase added to give 10 Cx units/l in the wash
** Alcalase added to give 10 gU/ml in the wash
Clay No. 1 is a bentonite having a cation exchange
capacity of 95 meg/lOOg while
Clay No~ 2 is a bentonite having a cation exchange
capacity of 31 meg/lOOg
Using the same evaluation method as described in
connection with Examples 1 and 2 the softness of terry
towelling monitors was assessed and the results were as
~ollows:
~5 Example No: Control D E 3 F G 4
% sotness 100 106 104 113 105 103 107
These results demonstrate that in the case of clay
No. 1, in comparison with the Control, the presence of
clay improves softening lExample D) and this softening is
further improved by the additional presence of cellulase
(Example 3) but not by the additional presence of alcalase
(Example E). The same conclusion can be drawn from the
results of those Examples which contain Clay No. 2.
lExamples F, G and 4). It is also apparent from these
results that Clay No. 1 shows improved results over Clay
No. 2, particularly in the presence of cellula~e (compare
Examples 3 and 4 ) .
..
