Note: Descriptions are shown in the official language in which they were submitted.
~: ~
`
~32~7
.
.,
'.1
,. .1
,.,
C 3 2 7 0
~,
:~ THICKENED LIQUIDS
! The present lnvention is concerned with the
thickening of liquids comprising polyalkoxylated
materiais.
.l Polyalkoxylates have recently been of interest in the
l~ detergents industry as components of non-aqueous liquid
cleaning products, especially when used as all or part of
a liquid phase in which particulate solids, such as
detergency builders, bleach.es, abrasives and mixtures
thereof, are dispersed.
There is ~ need for increasing the viscosity of
i 15 polyalkoxylates, whether or not formulated with dispersed
solids, for example for enhancing aesthetic appeal to the
consumer and aiding dispensing into washing machines via
.; ,.~
shuttle devices. When dispersed solids are present,
increased viscosity is advantageous in that it hinders
~ 20 settling of the particles of solid.
.."~:
.~ In searching fox an agent to thicken such liquids,
one may, inter alia think of using soluble polymers since
~.'.1 ~
`!
'`.,
~32~7
2 - C3270
there is already a wealth of knowledge on polymers for
thickening both aqueous and non-aqueous liquids. However,
when considering weakly polar liquids, polyalkoxylates in
particular, there is a scarcity of information.
Intuitively, one might expect polymers capable of hydrogen
bonding to the oxygen atoms in the alkoxylene groups, or
to a terminal hydroxy group would define those which are
soluble. However, we have failed to find this. Very many
such polymers, for example polyacrylates, polyacrylamides,
polyethylene oxides, polyvinyl acid esters and polyvinyl
alcohols axe all subs$antially insoluble at room
temperature in all or most of the liquid polyalkoxylates
of usual interest. Whilst in some cases, polyethylene
oxides can be dissolved at temperatures above 60C, they
precipitate out when the liquid is cooled.
Surprisingly however, we have found that
polyalkoxylate liquids may be thickened by dissolving
therein, certain polyvinylpyrrolidones or derivatives
thereof. Thus, according to the invention, there is
provided a non-aqueous liquid comprising a polyalkoxylated
material which liquid is thickened with a dissolved
vinylpyrrolidone polymer or a derivative thereof, which
polymer has a viscosity average molecular weight greater
25 than 30,00Q.
We have found that these particular polymars are
soluble at all accessible concentrations. However, since
the thickening power of a polymer increases more than
linearly with increasing molecular weight, molecular
weights above 100,000 especially above 250,000 ara
preferred, for example up to one million.
However, the amount of polymer material to produce a
given degree of thickening in a particular liquid phase
` ~32~7
- 3 - C3270
decr~ses with increasing polymer molecular weigh~.
Therefore the amount of polymer material incorporated in a
given system will vary widely according to the polymer
molecular weight, the pclyalkoxylated material(s) of the
S liquid solvent phase and, if present9 any other components
in the system, including any non-polyalkoxylated liquids.
As an example though, typical useful amounts of a polymer
material of 360 t 000 viscosity average molecular weight
will be from 0.5~ to 5~ by weight of the total
polyalkoxylated liquid.
There is a wide range of possible ways of expressing
polymer molecular weight, varying according to the
particular assay used and how the average is calculated
(e.g. number average, weight average, etc). However, the
term 'viscosity average molecular weight' when used in
respect of polyvinylpyrrolidones ~or soluble derivatives
thereof~ will readily be understood by those skilled in
the art and is widely used by manufacturers to
characterise such polymer products.
Although the polymer material exhibits the unexpected
advantage hereinbefore d~scribed, it can also endow
additional benefits in the wash which are already known
for such polymers when used in detergent compositions in
general. Thus, ~S patent 3 000 830 (Fong et al) describes
us~ of polyvinylpyrrolidone as a soil suspending agent arid
GB patent specification 1 348 212 (Procter and Gamble)~
published ~arch 13, 1974 di~closes use of polyYinyl
pyrrolidone and certain derivatives thereof for prevention
of dye transfer. We are also aware of European patent
specification EP-A-256 343 (Mira Lanza), published
February 24, 1988 which refers to the use of PVP with a
molecular weight of 3U, ono as a suspending agent in non-
acqueou~ liquid~.
_~,j;"
.~.i, ~
~32~7
- 4 - C3270
Although polyvinylpyrrolidones are readily
commercially available, in the light of the present
teaching, the man skilled in the art will now appreciate
that derivatives thereof with minor structural varia~ions
may be substitu~ed therefore with the expectation of
achieving the same effect, provided that any such
derivative is soluble in the liquid solvent phase. For
example, such derivatives may be co polymers containing
minor amounts of other monomer units. Such derivatives
may b~ any of those described in patent specification GB 1
348 212, published March 13, 1974.
The compositions of the invention must contain a
llquid polyalko~ylated material and must be such that the
polymer material is soluble therein, although it is
permissible for a portion of the polymer ma~erial to be
present as dispersed solid. The polyalkoxylated liquids
are chosen in particular for their ability to dissolve the
polymer material although cG-solvents may also be present,
provided that the polymer is soluble in the resul~ant
mixture. In the context of the present invention, a
polyalkoxyat~d ~laterial is any which has a molecule which
contains two or more alkoxylene groups, whether the same
25 or different, bonded directly to one another. All
references to liquids refer to materials which are liquid
at 25C at atmospheric pressure.
It is particularly preferred for all, or failing
3Q that~ a major amount, e.g. 50~ by weight or greater, of
the liquid phase to consist of one or more liquid
polyalkoxylated materials.
~specially preferred are liquid polyalXoxylated nonionic
surfactant~ such as are ~i~closed in our aforementioned EP-
A-266 199, published May 4, 1988.
- ~ 3 ~ 7
- 5 - C3270
Usually, these will be
chosen from liquid~ which are the condensation products Gf
fatty alcohcls with lower (C1 43 alkylene oxides~
- especially ethylene oxide and/or propylene oxides. Other
suitable polyalkoxylated liquids are poly-lower (C1 4)
alkylene glycols, especially liquid polyethylene glycols
and liquid polypropylene glycols. For example, the
polyethylene glycols may be chosen from those which are
liquid ~nd have molecular weights in the range of from 200
to 600. Also sui~able are alkylene glycol mono- or
dl-alkyl ethers. Such mono-alkyl ethers are disclosed in
British patenk s~ecificatio~ GB 2 169 613 (Col~ate-Palmolive),
puhlished February 16, 1986. Typically such di-alkyl
diethylene glycol di-ethyl or di-butyl ether (di-ethyl and
di-butyl C~rbitol, respectively), most preferably
di-ethylene glycol dimethyl ether (diqlyme). The polymer
material is insoluble in the latter liquid but when the
diglyme is mixed with a polyalkoxylated nonivnic
surfactant liquid or a liquid pGlyalkylene glycol,
especially a polyethylene glycol, then the polymer can be
dissolved, For example, the polymer can be dissolved in
mixtures of diglyme and polyethylene glycol, molecular
weight 200, in weight xa~ios from at least 1:3 to 3:1.
Where non-polyalkoxyl~ted co-solvents are also
included, these may be selected from any co-solvent which
is miscible with the liquid polyalkoxylated materials yet
do not cause insolubility of the polymer mater~al to the
extent that the thickening effect ls lost, Suitable
co-solvents are disclosed in ~aid EP-A-266 199, published
May 4, 1988.
Although the liquids of the present invention may
~ind application alone, they may al50 be formulated with
one or more other ingredients to provide liquid cleaning
product compositions. In particular, these other
ingredients may comprise a suspended particulate solid
denote~ trademark
. ..
~32~5~7
6 - C3270
phase. However, such other ingredients must be selected
so as to be compatible with the thickened liquid, i.e.
they must not destroy the thickening action exerted by the
polymer, although they may still act as 'thinners'. The
compositions may be formulated in a very wide range of
specific forms, according to the intended use. They may
be formula~ed as cleaners for hard surfaces (with or
without abrasives) or as agents for warewashing (cleaning
of dishes, cutlery etc) either by hand or mechanical
means, as well as in the form of specialised cleaning
products, such as for surgical apparatus or artificial
dentures. They may also be formulated as agents for
washing and/or conditioning of fabrics.
In the case of hard-surface cleaning, the
compositions may be formulated as main cleaning agents, or
pre-treatment products to be sprayed or wiped on prior to
removal, e.g~ by wiping off or as part of a main cleaning
operation.
In the case of warewashing, the compositions may also
be the main cleaning agent or a pre-treatment product,
e.g. applied by spray or used for soaking utensils in an
aqueous solution andtor suspension thereof.
Those products which are formulated for the cleaniny
and/or conditioning of fabrics constitute an especially
preferred form of the present invention because in that
role, there is a very great need to be able to incorporate
substantial amounts of vaxious kinds of solids. These
compositions may for example, be of the kind uced for
pre-treatment of fabrics (e.g. for spot stain removal)
with the composition neat or diluted, before they are
rinsed and~or subjected to a main wash. The compositions
may also be formulated as main wash products, being
dissolved and/or dispersed in the water with which the
.
~32~
- 7 - C3270
fabrics are contacted. In that case, the composition may
be the sole cleaning agent or an adjunct to another wash
product. Within the context of the present invention, the
term 'cleaning product' also embraces compositions of the
kind used as fabric conditioners (including fabric
softenersJ which are only added in the rinse water
(sometimes referred to as 'rinse conditioners')O
Thus, the compositions will contain at least one
agent which promotes the cleaning and/or conditioning of
the article(s) in question, selected according to the
intended application. Usually, this agent will be
selected from surfactants, enzymes, bleaches,
microbiocides, (for fabrics) fabric softening agents and
(in the case of hard surface cleaning) abrasives. Of
course in many cases, more than one of these agents will
be present, as well as other ingredients commonly used in
the relevant product form.
The compositions will be substantially free from
agents which are detrimental to the article(s) to be
treated. For exampls, they will be substantially free
from pigments or dyes, although of course they may contain
small amounts of those dyes (colourants) of the kind often
used to impart a pleasing colour to liquid cleaning
products, as well ai~ fluorescers, bluing agen~s and the
like.
Any other ingredients before incorporation will
either be liquid, in which case, in the composition they
will constitute all or part of the liquid phase, or they
will be solids, in which case, in the composition they
will either be dispersed particles in the liquid phase or
they will be dissolved therein. Thus as used herein, the
term ~solids" is to be construed as referring to materials
in the solid phase which are added to the composition and
1 3 ~ 7
- ~ - C3270
are dispersed therein in solid form, thGse solids which
dissolve in the solvent and those in the liquid phase
which solidify (~Indergo a phase change) in the
composition, wherein they are then dispersed.
Thus, where surfactants are solids, they will usually
be dissolved or dispersed in the liquid phase. Where they
are liquids, they will usually constitute all or part of
the liquid phase. However, in some cases the surfactants
may undergo a phase change in the composition. In
general, they may be chosen from any of the classes,
sub-classes and specific materials described in 'Surface
Active Agents' Vol.I, by Schwartz & Perry, Interscience
1949 and 'Surface Active Agents' Vol.II by Schwartz, Perry
15 h Berch (Interscience 1958), in the current edition of
"McCutcheon's Emulsifiers & DeteryentsU published by the
McCutcheon division of Manufacturing Confectioners Company
or in 'Tensid-Taschenbuch', H.Stache, 2nd Edn., Carl
Hanser Verlag, M~nchen & Wien, 1981.
Nonionic detergent surfactants, both liquid and
solid, ~re well-known in the art. They normally consist
of a water-solubilizlng polyalkoxylene or a mono- or
di-alkanolamide group in chemical combination with an
organic hydrophobic group derived, for example, from
alkylphenols in which the alkyl group contains from about
6 to about 12 carbon atoms, dialkylphenols in which each
alkyl group contains from 6 to 12 carbon atoms, primary,
secondary or tertiary aliphatic alcohols (or alkyl-capped
derivatives thereof), preferably having from 8 to 20
carbon atoms, monocarboxylic acids having from 10 to about
24 carbon atoms in the alkyl group and polyoxypropylenes.
Also common are fatty acid mono- and dialkanolamides in
which the alkyl group of the fatty acid radical contains
from 10 to about 20 carbons atoms and the alkyloyl group
having from 1 to 3 carbon atoms. In any of the mono- and
1:~245~7
- g - C3270
di- alkanolamide derivatives, opti~nally, there may be a
polyoxyalkylene moiety joining the latter groups and the
hydropho~lc part of the molecule. In all polyalkoxylene
containing surfactants, the polyalkoxylene moiety
preferably consists of from 2 to 20 groups of ethylene
oxide or of ethylene oxide and propylene oxide groups.
Amongst the latter class, particularly preferred are those
described in European speci$ication EP-A-225 654
(Unilever). Also preferred are those ethoxylated
nonionics which are the condensation products of fatty
alcohols with from 9 to 15 carbon atoms condensed with
frol~l 3 to 11 moles of ethylene oxide. Examples of these
are the condensation products of C11 13 alchols with (say)
3 or 7 moles of ethyiene oxide. These may be used as the
sole nonionic surfactants or in combination with those of
the described in the last-mentioned European
specification.
Another class of suitable nonionics comprise the
alkyl polysaccharides (polyglycosides/oligosaccharides3
such as d~scribed in any of specifications US 3 640 998;
US 3 346 558; US 4 223 129; EP-A-92 355; EP-A-99 183;
EP-A-70 074, '75, '76, '77; EP-A-75 994, '95, '96.
Mixtures of different nonionic detergent surfactants
may also be used, provided the mixture is liquid at room
temperature. Mixtures of nonionic detergent surfactan~s
with other ~etergent surCactants such as anionic, cationic
or ampholytio detergent surfactants and soaps may also be
used. If such mixtures are used, the mixture must be
liquid at room temperature.
Examples of suitable anionic detergent surfactants
are alkali metal, ammonium or alkylolamine salts of
alXylbenzene sulphonates having from 10 to 18 car~on atorns
in the alkyl ~roup, alkyl and alkylether sulphates ha~ing
~32~5~7
- 10 - C3270
from 10 to 24 carbon atoms in the alkyl group, the
alkylether sulphates having from 1 to 5 ethylene oxide
grGups, olefin sulphonates prepared by sulphonation of
C10-C24 alpha-oleflns and subsequent neutralization and
hydrolysis of the sulphonation reaction product.
Other surfactants which may be used include alkali
metal soaps of a fatty acid, preferably one containing 12
to 18 carbon atoms. Typical such acids are oleic acid,
ricinoleic acid an~ fatty acids derived from caster oil,
rapeseed oil, ground nut oil, coconut oil, palmkernal oil
or mixtures thereof. The sodium or potassium soaps of
these acids can be used. As well as fulfilling the role
of surfactants, soaps can act as detergency builders or
fabric conditioners, other examples of which will be
described in more detail hereinbelow. It can also be
remarked that the oils mentioned in this paragraph may
thenlselves constitute part of the liquid, whilst the
corresponding low molecular weight fatty acids
(triglycerides) can be dispersed as solids or function as
structurants.
Yet again, it is also possible to utilise cationic,
zwitterionic and amphoteric surfactants such as referred
~5 to in the general surfactant te~:ts referred to
hereinbefore. Examples of cationic detergent surfactants
are aliphatic or aromatic alkyl-di(alkyl) ammonium halides
and examples of soaps are the alkali metal salts of
C12-C24 fatty acids. Ampholytic detergent surfactants are
e.g. the sulphobetaines. Combinations of surfactants from
within the same, or from different classes may be employed
to advantage for optimising structuring and/or cleaning
performance.
The compositions according to the present invention
preferably also contain one or moxe other functional
1 324~57
- 11 - C3270
ingredients, for example selected from detergency
builders, bleaches or bleach systems, and (for hard
surface cleaners) abrasives.
Detergency builders are those materials which
counteract the effects of calcium, or cther ion, water
hardness, either by precipitation or by an ion
sequestering effect. They comprise both inorganic and
organic builders. They may also be sub-divided into the
phosphorus-containing and non-phosphorus types~
In general, the inorganic builders comprise the
v~rious phosphate , carbonate-, silicate-, borate and
aluminosilicate-type materials, particular the
alkali-metal salt forms. Mixtures of these may also be
used .
Examples of phosphorus-containing inorganic builders,
when present, include the water-soluble salts, especially
alkali metal pyrophosphates, orthophosphates,
polyphosphates and phosphonates. Specific examples of
inorganic phosphate builders include sodium and potassium
phosphates and hexametaphosphates, as well as sodium and
potassium tripolyphosphate.
Examples of non-phosphorus-containing inorganic
builders, when present, include water~soluble alkali metal
carbonates, bicarbonates, borates, silicates,
metasilicates, and crystalline and amorphous alumino
silicates. Specific examples include sodiu~ carbonate
(with or without calcite seeds), potassium carbonate,
sodium and potassium bicarbonates, silicates and zeolites.
The aluminosilicates are an especially preferred
class of non-phosphorus inorganic builders. These for
~245~7
- 12 - C3270
example are crystalline or amorphous materials having the
general formula:
Naz (A102) æ (Sio2)y x ~2
wherein Z and Y are integers of at least 6, the molar
ratio of Z to Y is in the range from 1.0 to 0.5, and x is
an integer from 6 to 189 such that the moisture content is
from about 4~ to about 20% by weight (t~rmed herein,
'partially hydrated'). This water content provides the
~est rheological properties in the liquid. Above this
level (e.g. from about 19~ to about 28~ by weight water
content), the water level can lead to network formation.
Below this level (e~g. from 0 to about 6~ by weight water
content), trapped gas in pores of the material can be
displaced which causes gassing and tends to lead to a
viscosity increase also. The preferred range of
aluminosilicate is from about 12~ to about 30% on an
anhydrous basis. The aluminosilicate preferably has a
20 particle size of from 0.1 to 100 microns, ideally between
0.1 and 10 microns and a calcium ion exchange capacity of
at least 200 mg calcium carbonate/g.
Examples of organic builders include the alkali
metal, ammonium and substituted ammonium, citrates,
succinates, malonates, fatty acid sulphonates,
carboxymethoxy succinates, ammonium polyacetates,
carboxylates, polycarboxylates, aminopolycarboxylates,
polyacetyl carboxylates and polyhydroxysulphonates.
Specific examples include sodium, potassium, lithium,
ammonium and subs~ituted ammonium salts of
ethylenediaminetetraacetic acid, nitrilotriacetic acid,
oxydisuccinic acid, melitic acid, benzene polycarboxylic
acids and citric acid. Other examples are organic
phosphonate type sequestering agents such as those sold by
~2~
- 13 C3270
~lonsanto u~der ~he tradename of the De~uest range and
alkanehydroxy phosphonates.
Other suitable organic buildèrs include the higher
molecular weight polymers and co-polymers known to have
builder properties, for example appropriate polyacrylic
acid, polymaleic acid and polyacrylic/polymaleic acid
co-polymers and their salts, such as those sold by sASF
under the Sokalan Trade Mark.
Suitable bleaches include the halogen, particularly
chlorine bleaches such as are provided in the form of
alkalimetal hypohalites, e~g. hypochlorites. In the
application of fabrics washing, the oxygen bleaches are
preferred, for example in the form of an inorganic
persalt, preferably with an precursor, or as a peroxy acid
compound.
.
In the case of the inorganic persalt bleaches, the
precursor makes the bleaching more effective at lower
temperature~, i.e. in the range from ambient temperature
to about 60C, so that such bleach systems are commonly
known as low-temperature bleach systems and are well known
in the art. The inorganic persalt such as sodium
perborate, both the monohydrate and the tetrahydrate, acts
to release active oxygen in solution, and the precursor is
usually an organic compound having one or more reactive
acyl residues, which cause the ~ormation of peracids, the
latter providing for a more effective bleaching action at
lower temperatures than the peroxybleach compound alone~
The ratio by weight of the peroxy bleach compound to the
precursor is from about 15:1 to about 2;1, preferably from
about 10:1 to about 3.5:1. Whilst the amount of the
bleach system, i.e~ peroxy bleach compound and precursor,
nlay be varied between about 5~ and about 35% by weight of
i the total li~uid, it is preferred to use from about 6% to
Olen~) tra~e~
''' ' . ' ~ , ` ' - , :
~3:2~7
14 C3270
about 3~ of the ingredients forming the bleach system.
Thus, the preferred level of the peroY~ bleach compound in
the composition is between about 5.5~ and about 27% by
weight, while the preferred level of the precursor is
be$ween about 0.5~ and about 40~, most preferably between
about 1% and about 5% by weight.
Typical examples of the suitable peroxybleach
compounds are alkalimetal perborates, both tetrahydrates
and monohydrates, alkali metal percarbonates, persilicates
and perphosphates, of which sodium perborate is preferred.
Precursors for peroxybleach compounds have been amply
described in the literature, including in British patent
cpecifications 836 988, 855 735, 907 356, 907 358,
907 950 t l 003 310 and 1 246 339, US patent specifications
3 332 882, and 4 128 494, Canadian patent specification
844 481 and South African patent specification 68/6344.
The exact mode of action of such precursors is not
known, but it is believed that peracids are formed by
reaction of the precursors with the inorganic peroxy
compound, which peracids then liberate active-oxygen by
decomposition~
They are generally compounds which contain N-acyl or
O-acyl re idues in the molecule and which exert their
activating action on the peroxy compounds on contact with
these in the washing liquor. Cationic peracid bleach
precursors such as those described in United States patent
specifications US 4 751 015 and US 4 397 757 (~ever Bros)
can be included.
When the composition contains abrasives for hard
surface cleaning (i.e. is a liquid abrasive cleaner),
these will inevitably be incorporated as particulate
,: . ,
' ' ; '
- ~32~55~
- 15 - C3270
solids. They may be those of the kind which are water
lnsoluble, for example calcite. Suitable materials of
this kind are disclo~ed in patent specifications
EP-A-50 887; EP-A-80 221; EP-A-140 452; EP-A-214 540 and
EP 9 942 (all Unilever), which relate to such abrasives
when suspended in aqueous media. Water soluble abrasives
may also be used.
The compositions according to the present invention
may also contain an auxiliary dispers~nt such as finely
divided metal or metaloid oxides as referred to in patent
specifications Gs 1 205 711 and 1 270 040 or fine
particulate chain-structure clay as described in European
speciflcation EP-A-34 387 (Procter & Gamble). They may
lS also contain one or more of the deflocculants disclosed in
EP-A-265 199, for example dodecyl benzene sulphonic acid
(added in the free acid form) or lecithin.
:
The compositions of the invention optionally may also
0 contain one or more minor ingredients such as fabric
conditioning agents~ enzymes, perfumes (including
deoperfumes), micro-biocides, colo~lring agents,
fluorescers, soil-suspending agents (anti-redeposition
agents), corrosion inhibitors, enzyme stabilizing agents,
and lather depressants.
: :
The compositions are substantially non-aqueous, i.e.
they contain little or no free water, preferably no more
than 5%, preferably less than 3~, especially less than 1
by weight of the total composition. It has been found
that the higher the water content~ the more likely it is
for the viscosity to be too high, or even for setting to
occtlr O
Since the objective of a non-aqueous liquid will
generally be to enable the formulator to avoid the
:
~32~5~7
- 16 - C3270
negative influence of water on the components, e.g.
causing ~ncompatability of functional ingredients, it is
clearly necessary to avoid the accidental or deliberate
addition of water to the product at any stage in its li~e.
For this reason, special precautions are necessary in
manufacturing procedures and pack designs for use by the
consumer.
~hus during manufacture, it is preferred that all raw
materials should be dry and (in the case of hydratable
salts) in a low hydration state, e.g. anhydrous phosphate
builder, sodium perborate monohydrate and dry calcite
abrasive, w~lere these are employed in the composition. In ! ,
a preferred process, any solids in dry, substantially
anhydrous form, are blended with the liquid phase in a dry
vessel. In order to minimise the rate of sedimentation of
the solids, this blend is passed through a grinding mill
or a combination of mills r e.g. a colloid mill, a corundum
disc mill, a horizontal or vertical agitated ball mill, to
20 achieve a particle size of 0.1 to 100 microns, preferably
0.5 to 50 microns, ideally l to 10 microns. A preferred
combination of such mills is a colloid mill followed by a
horizontal ball mill since these can be operated under the
conditions required to provide a narrow size distribution
in the final product. Of course particulate material
already having the desired particle size need not be
~ubjected to this procedure and if desired, can be
incorporated during a later stage of processing.
During this milling procedure, the energy input
results in a temperature rise in the product and the
liberation o~ air trapped in or between the partlcles of
the solid ingredients. It is therefore highly desirable
to mi~ any heat sensitive ingredients into the product
after the milling stage and a subsequent cooling step. It
~,ay also be preferable to add the polymer at this stage so
` ; `
:~ 3 ~
- 17 C3270
as to avoid mechanical degradation thereof. It may also
be desirable to de-aerate the product before addition of
these (usually minor) ingredients and optionally, at any
other stage of the process. Typical ingredients which
might be added a~ this stage are perfumes and enzymes, but
might also include highly temperature sensitive bleach
components or volatile solvent components which may be
desirable in the final composition. However, it is
especially preferred that volatile material be introduced
after any step of de-aeration. Suitable equipment for
cooling (e.g. heat exchangers) and de~aeration will be
known to those skilled in the art.
It follows that all equipment used in this process
should be completely dry, special care being taken after
any cleaning operations. The same is true for subsequent
storage and packing equipment.
The present invention will now be demonst~ated by way
of the following non-limiting examples.
Example l
Various polymers as indicated below were separately
~5 added at 0.5g each to lOOg batches of Dobanol 91/6T
(nonionic surfactant, Cg 11 fatty alcohol alkoxylated with
an average of 6 moles of ethylene oxide per molecule, ex
Shell~ and the solubility determined.
` ` 1 3 ~
- 18 ~ C3270
Polymer M Solubility at:-
Room 70C
Temp
5 Polyvinyl alcohol25,000
(88~ hydrolysed)
Hydroxypropyl600,000
cellulose
Polyvinylacetate45,000
Polyvinylpyrrolidone 360,000 + +
Polyethyleneoxide300,000 - ~
.
Polystyrene 100,000 - -
Polyacrylic acid38,000
Polystyrene sulphonate 70,000
Solubility: + soluble
- substantially insoluble
It is evident that only the polyvinylpyrrolidone was
soluble at room temperature. It produced a readily
perceptible thickening of the nonionic surfactant.
.
To determine thickening effects with non-surfactant
po1yalkoxy1ated so1vents, experiments were performed with
i
t32~S57
- 19 - C3~70
liquid polyethylene glycol, MW 200 (PEG 200) ex BDH and
diglyme, ex Fluka Chemie AG.
It was found that 2g of PVP (polyvinylpyrrolidone,
MW 36G,000 ex Polysciences Inc) dissolved in 20g of the
PEG 200 to give a clear solution with a noticeable
increase in viscosity over the PEG 200 alone.
It was found that the PVP at 0.2g was substantially
insoluble in 20g of the diglyme alone. Therefore the
miscibility of the PEG 200 with the diglyme was
investigated. The two solvents were found to be
completeiy miscible in mixtures of 2.5g/7.5g, 5.0g/5.0g
and 7.5g/2.5g respectively.
It was found that the PVP was soluble at 0.5% wtw in
2.5g PEG 200 mixed with 7.5g diglyme and gave a clear
solution although the observable thickening effect was
marginal. However, the PVP at 4.5% w/w in 5g PEG 200
mixed with 5g diglme gave not only a clear solution but a
definite perceptible increase in viscosi~y relative to the
diglyme alone.
le 3
10% by weight solutions of polyvinylpyrrolidone
having a molecular weight of lOK, 24K, 40K and 360K in
Dobanol 91-6T were prepared and the equilibrium flow curve
for each sample was measured using a Rheo-Tech
International Visco-Elastic Rheometer over a torque range
of l to 5 mNm. From the plots of viscosity against shear
rate, it was apparent that the samples containing PVP with
a molecular weight up to 40K gave no measurable change in
viscosity with increasing shear rate. The measured
viscosities were extrapolated to a shear rate of 21s 1
with the following results~
; , , , , . : :
~32~57
- 0 - C3270
Molecular wei ~ Vi~
-
10,000 0.13
24,000 0.22
40,000 0.27
The sample containing PVP with a molecular weight of
360,000 was found to be shear thinning, having a viscosity
of 6.24 Pas at 21s 1 which was even higher at lower shear
rates, indicative of significant thickening.
These results show that a substantial increase ir,
thickening occurs when polymers with higher molecular
weights are used.
Example 4: Full~ formulated compositior.
wt ~
Dobanol 91/6T (1) 37.85
~: Glycerol tri-acetate 5.0
Aerosil 380 (2) 1.25
PVP (3) 0.5
STP ~4)
25 Sodium carbonate Oaq 4.0
Na Perborate monohydrate 15.0
: EDTA (5) 0.15
SCMC (6) 1.0
TAED (7) 4.0
3G Dequest 2041 0.1
FIuorescer (Tinopal D~S X) 0.3
Tylose MH20 0.5
Silicone DB100 0.25
~Savinase 8.0 SL 0.6
t~ em~rK
- ~
~ 3 ~ 7
- 21 C3270
(1) as Example 1.
(2) Finely divided silica
(3~ Molecular weight 360,000
(4) Sodium tripolyphosphate
(5) Ethylene diamine tetraacetic acid
(6) Sodium carboxymethylcellulose
(7~ Tetraacetyl ethylenediamine
