Note: Descriptions are shown in the official language in which they were submitted.
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l ~ This inventLon relates to an improved bubblebath for-
... . .
mulation in dry powder form. More particularly this in-
vention relates to an alcohol ether sulfate composition in
the form of spray-dried beads particularly suitable for use
as a bubblebath formulation.' :
' Considerable difficulty is encountered during the formu- '
lation of commercially acceptable alcohol ether sulfate based
dry powder detergent compositions. More specifically, the
adaptation of the conventional spray-drying methods of manu-
I facture to substantially neutral compositions whe'rein signif-
icant amounts of alcohol ether sulfate are present, i.e. 7-8C/o
~ - ' and more, has not been readily-accomplished heretofor. Pre-
- vious attempts to spray dry siurries containing significant
proportions of an alcohol ether sulfate product have resulted
in serious'difficulties with regard to'tackiness of the fin-
ished product. It is important that commercially acceptable
spray-dried beads retain the form of-a hollow, spherical bead,
this form being important for a fast dissolving product. More-
~': - '
over, for compositions such as bubblebaths which contain amounts
i'~ of active ingredient of about 7-20%, for instance, spray dry-
~ ing is a desirable economical method'of production. '
- The present invention discloses a detergent composition
which is particularly amenable to the spray-drying process
and with the further prov'ision of forming spray-dried beads.
' It is an object of this invention to provide a composition
.~ .
'' ' ~ for forming spray-dried beads suitable in a bubblebath formu-
lation', which beads are substantially dust free, low in den-
sity and which will withstand packaging and transport without
- breaking down.
~ ~ -2-
~' '',' " ' .`'` ' .
-~ ~0~841Z
It is ~urtller an object of this invention to provide a
s~ray-dried alcohol e~her-sulfate detergen~ product whicll will
remain pH stable durin~ spray drying and for long periods under
normal conditions of storage and transport.
Ie is a further object of this invention to provide a com-
position having a neutral pH, i.e. pH of between 6.0-~.0, which
lends itself to rapid spray drying at high temperatures, i.e.
about 700F, without decomposition.
It is a further object of this invention to provide a method
of spray drying slurries containing significant proportions of an
alcohol ether sulfate to form hollow spherical beads which are
substantially dust-free. - -
, . _ . ~
Another object of the invention is to provide a method of
~spray drying slurries containing significant proportions of an
alcohol ether sulfate which will res~lt in the formation of
beads with properties that are particularly suitable ror use as
~bubblebath compositions.
~ .
Other objects of the invention will be apparent from the
-~ following detailed descriptions. ~ - ;
- In accordance with the present invention there is provided
-
dry.powder detergent compositions~in the form of spray-dried
beads which comprise an alcohol ether sulfate, hydrate forming
salt and a buffer.~
: The aforesaid beads are prepared quite readily by conven-
tional spray drying techniques. Tbe composi~ions of the pre-
8ent invention are in the form of hollow, sphèrical beads which
. .
retain their physical form,are free-1Owing, have suppressed
dusting tendencies, exhibit good foaming characteristics for
use-as a bubblebath formulation, and have a bulk density within
- ' - : ................ . , - , ~
- -3- .
.
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1 a commercially acceptable range.
The alcohol ether sulfates employed in the composition
of the present invention may be described as having the
general formula RO(CH2CH2O)x-SO3-M wherein R is an alkyl
chain having from about 10 to 18 carbon atoms, x is an integer
from about 2 to 6 and M is a cation.
The alcohol ether sulfates can be made by the condensation,
by known methods, of ethylene oxides on the monohydric al-
cohols having 10 to 18 carbon atoms. Preferably, R has 12 to
15 carbon atoms. The alcohols may be derived from fats, e.g.,
coconut oil, or they may be synthetic. Lauryl alcohol and
straight chain alcohols derived from coconut oil are preferred.
Such alcohols are reacted with 2 to 6, and especially 3 to 5
molar proportions of ethylene oxide and the resulting mixture
of molecular species, having, for example, an average of 3
moles of ethylene oxide per mole of alcohol, is sulfated and
neutralized.
The cation M may be alkali metal, ammonium, substituted
ammonium radical, a~aline earth metal, or a mixture of any
two or more of these. The aforesaid alcohol ether sulfates
are employed in amounts ranging from about 5% to 12% by weight
of the overall composition and preferably in the range of
about 7 to 9% by weight of product. For optimum results, it
has been found that the aforesaid sulfated surfactant should be
be derived from alkanols having from 12 to 15 carbon atoms or
mixtures of such alkanols, the degree of ethoxylation should
be in the range of about 3 to 5 mols of ethylene oxide per
mol of alkanol, and the alcohol ether sulfate should preferably
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be employed in the form of the sodium salt.
The second component of the composition is a hydrate
forming salt and preferably one such as magnesium sulfate.
The magnesium sulfates useful in these compositions may take
the form of any of the commercial grades of magnesium sulfate,
such as epsom salts or magnesium sulfate heptahydrate. The
magnesium sulfate is present in an amount of from about 5 to
15% of the total composition and preferably at about the 10%
level.
The third component of the composition is a buffer.
The buffer is employed for the purpose of preventing acid cata-
lyzed decomposition. The buffer acts to insure stability by
adjusting the pH of a 5% by weight solution to a value between
6 and 8. Preferred buffers include the salts of citric, maleic
or phosphoric acid as well as mixtures of these salts. The
buffer is present in an amount of from about 0.25 to 2.5% of
the total composition and preferably at the 1.5% level.
... .
A particularly preferred buffer is a combined buffer
system of about 0.5% by weight of a citrate and about 1.0% by
weight of a phosphate. Particularly suitable is a combination
as aforesaid of disodium phosphate and trisodium citrate. This
citrate-phosphate buffer system provides a stable pH of between
about 6.0 and 7.0 over long periods of time of about 4 months
or more.
While the essential principal ingredient is an alcohol
ether sulfate, small percentages of additional detergents may
also be employed providing they do not impair the performance
of the aforesaid combination of alcohol ether sulfate, ........
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:1048412
1 magnesium sulfate and buffer.
Additionally the compositions of the present invention
may contain a water-soluble starch hydrolysate which is a
starch carbohydrate which has been subjected to acid or enzyme
(amylase, e.g.) catalyzed hydrolysis. These materials are
utilized within the range of 1 to 3% by weight of the composi-
tion. These hydrolysates, which are employed preferably at
about the 2% level, are characterized as having a dextrose
equivalent between about 15 and 44. Particularly preferred
are corn starch hydrolysates which have a dextrose equivalent
` of 15 to 20. The starches may also be derived from sources such
as wheat, rice, potato and the like. These water-soluble starch
hydrolysates are composed mainly of higher polysaccharides but
significant proportions of di- to hexasaccharides are also
present.
The compositions of the present invention may also con-
tain sodium chloride which is used generally in the 8 to 12%
range and preferably at the 10% level.
A further ingredient which may be present is a sodium or
potassium sulfate filler, such as sodium sulfate and the like.
2 The exact amount will, of course, be dependent on the quanti-
ties of other components used. Generally speaking, the amount
will vary over the 40 to 60% range and preferably within the
range of 50 to 55% by weight.
The compositions of the present invention may contain other
ingredients useful in dry powder detergent compositions, such
as perfumes, coloring agents, bacteriocides, sequestering
- -- 104841Z
1 agents and tlle like. Such additives may be incorporated either
- before or after the spray drying is carried out.
The composition as aforesaid is formed into a.slurry, and
the slurry is then forced through spray nozzles into towers
wherein the small liquid particulates are dried as they contact
a stream or vortex of heated air. The composition is produced
- - thereby in the form of hollow, thinwalled spheres or beads
having a low apparent bulk density of about 0.20 to 0.25 gram
- " per cc., and characterized by excellent solubility, good foaming
~10 properties, uniformity of particles which are essentially non-
tacky, dust-free andtherefore provide a product with good pack-
- aging properties as well as beLng particularly suitable for
use as bubblebath formulations.
- ~ The spray drying conditions are somewhat variable and
. .
generally air inlet temperatures of 700 to 840F and air
outlet temperatures of 200 to 260 F are used. The pressure
at which the slurry is pumped to the spray nozzles may be in
~ . - . .
-~ - the range of 250 to 600 p.s.i.g. The slurry coneentration
- ~ ~ will be from 40 to 70% by weight with a-concentration of about
507O by weight solids prodùcing the best viscosity.
~; - The invention is further illustrated by the following
. examples which are not to be considered as limitative of
its scope. All percentages are by weight or as otherwLse in-
dicated.
~ ~. -' ' , - , .
~- ~ ' ' - .
EXAMPLES 1-~
Spray dried bubblebath compositions were prepared having
the following compositions:
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Component 1 2
Alcohol ether sulfatel 7.5% 8.0%
MgS043 10.0% 10.0%
Disodium Phosphate 1.0% 1.0%
Trisodium Citrate 0.5% 0.5%
Modified Starch2 2.0% 2.0%
NaCl 10.0% 10.0
Na2S4 R7. R7.
Water 2.0% 2.0%
Surfactant4- 0.2% 0.2%
Perfume5- 0.15% 0.10%
CDA6. 0.5%
notes:
1. sodium salt, mixture of Cl2 to Cl5 linear mono-
hydric alkanols containing 4 moles of ethylene oxide
per mole of alkanol.
2. mixture of mono-, di-, and polysaccharides
3. filler
4. ethoxylated coconut fatty acid monoethanolamide
having 5 ethoxy groups
5. Florasynth 1768-1* (Fragance)
6. coconut diethanolamide
7. remainder
8. heptahydrate, weight on anhydrous basis
The aforesaid compositions were prepared by spray dry-
ing from a slurry having a concentration of from 50 to 55% solids
which was pumped at a pressure of from 250 to 350 psig. The
spray dry tower air inlet temperature was 750 F.
* Trademark
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1~)48~12
1 The product produced was a free-flowing, essentially dust-free
product having less than 0.5% by weight through 200 mesh.
Any minimal dust settled rapidly. The pH of the product at
packaging was 6.9 - 7.0 and remained stable over a period
of about 4 months.
Compositions similar to those of Examples 1 and 2
but having 5.0% and 15.0% magnesium sulfate also provide
acceptable spray dried products.
EXAMPLES 3-7
For comparative purposes, spray dried compositions are
prepared with other detergent materials and having the
following ranges of proportions. Spray drying conditions
are similar to those of the aforesaid Examples. Comments
are given below ~ith regard to the properties of each of
the spray dried products produced.
Component 3 4 5 6 7
(a) 15% 10% 15% 10% 2%
(b) 5% 5% none 2% 2%
(c) 5% 5% 10% 2% none
(d)none none 15% 5% 20%
(e) 15% 15% none 10% 10%
(f) 60% 65% 60% 73% 66%
notes:
(a) Sodium C14-C16 alpha-olefin sulfonate
(b) Sodium n-dodecyl benzene sulfonate
(c) Water soluble corn starch hydrolysate having a
dextrose equivalent of 15-20
_g_
~-~ .
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1 (d) Magnesium sulfate heptahydrate
(e) Sodium Chloride
(f) Sodium Sulfate
Example 3: A relatively high density product, about 0.3 g/cc
is produced and the bead is too fragile for packaging operations.
ExamPle 4: An extremely dusty product is obtained with wide
variations in density.
Example 5: Again the product dusts excessively.
ExamPle 6: A very high density product, 0.4 - 0.5 g/cc. is
obtained which dusts excessively.
ExamPle 7: The product is extremely dusty.
Although the present invention has been described with
reference to particular embodiments and examples, it will be
apparent to those skilled in the art that variations and
modifications of this invention can be made and that equival-
ents can be substituted therefor without departing from the
principles and true spirit of the invention.
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