Note: Descriptions are shown in the official language in which they were submitted.
CA 02586725 2007-04-26
WO 2006/046945 PCT/US2004/035006
~rrraaararaaararawaaaraarwrrrrrrraaraaaraaawaarraaaaraaraaa~rarrrrrrrrrrrrr~
ACTIVATED ALUMINUM/DEPOLYMERIZED ZIRCONIUM ANTIPERSPIRANT
COMPOSITIONS
~rrarrrrrwaarrarraaaraarraaaararrwaawrarrraarrrrrrrrrrrraraaarrraarararrawr~
CA 02586725 2007-04-26
WO 2006/046945 PCT/US2004/035006
This invention relates to aluminum-zirconium antiperspirant compositions of
enhanced efficacy comprising activated aluminum and depolymerized zirconium
species and
the metliods of making said compositions.
BACKGROUND OF THE INVENTION
Antiperspirants of enhanced efficacy usually have high SEC-HPLC Band III, with
Band III to Band II area ratio of at least 0.5. The activation of aluminum is
achieved by the
dilution and heat treatment of aluminum chlorohydrate (ACH) solution. Heating
the inore
diluted ACH solution for a longer period of time produces an activated
aluininum
antiperspirant with higher Band III/II ratio. The Band III aluminum species
are generally
very reactive and quickly revert back to Band II aluminum species. The
activated aluminum
solutions are dried to powders in order to preserve their eiihanced efficacy.
Prior art describing the preparation of such salts include the following:
U.S. Patent No. 4,359,456 which describes a process of heating 2.5% to 8.5% by
weight ACH solution at 50 C to 140 C from 0.5 hour to 30 days that gives a
composition
having SEC-HPLC Band III of at least 20% aluminum.
GB2048229A describes an activated aluininum salt made by aging or heating from
5% to 40% by weight ACH from 50 C to 100 C. The patent does not disclose any
preferred
SEC-HPLC profile.
U.S. Patent No. 4,944,933 discloses a direct process of making activated basic
aluminum chlorohydrate solution at 7.5% to 13% by weight having an aluminum to
cliloride
ratio of 1.7:1 to 2.2:1 and a Band III fraction of at least 20%.
U.S. Patent No. 5,356,609 describes a process of malcing basic aluminum
chloride
solution with high Band III of at least 25% by the direct reaction of A1C13
solution with Al
powder at 50 C to 100 C and at a conceiltration of about 8% to about 25% by
weight. The
product has a large amount of Alb species.
U.S. Patent Publication No. 2004/0101500 Al provides a method of making an
activated aluminum salt solution having a ratio of aluminum to chloride
ranging from 1.5:1 to
2.0:1 and an aluminum concentration ranging from 0.5% to 3.8% by weight. Heat
treatment
of the solution is involved. The aluminum salt has a ratio of SEC-HPLC Band
III to Band II
of greater than 3:1.
Activated aluminum-zirconium antiperspirant salts are produced by the addition
of
zirconium compounds to the activated aluminum solutions, which are dried to
powders due to
2
CA 02586725 2007-04-26
WO 2006/046945 PCT/US2004/035006
the fast change of Band III into Band II in solution fornis that result in the
loss of efficacy of
the corresponding salts. The introduction of zirconium species into these
aluminum salt
solutions fiu-ther depolymerize the aluminum species, which results in a
change in the
distribution of aluminum species and an increase in efficacy is observed. The
zirconium
species, on the other hand, become further polymerized during the process and
the effect is
more pronounced wlien activated aluminum solutions are involved. Patents
describing the
preparation of such activated aluminum-zirconium antiperspirant salts include:
U.S. Patent No. 4,775,528 which discloses an aluminum-zirconium solid
composition
of enhanced efficacy. The process of making includes firstly, heating a 2% to
18% by weiglit
ACH solution at a teinperature of at least 50 C for a certain period of time,
secondly mixing
zirconium hydroxy chloride with the solution before, during or after the heat
treatment of the
diluted ACH solution and thirdly drying the solution to a powder. No
differences in the final
compositions were observed between addition of the zirconium species to the
aluminum
solution before, during or after the heat treatment. The sequence of the
addition however, has
a substantial effect on the degree of polymerization of the zirconium species.
The aluminum-
zirconium salts prepared according to U.S. Patent No. 4,775,528 show a large
SEC-HPLC
peak 1, which is an indication that the zirconium species are greatly
polyinerized.
U.S. Patent No. 4,871,525 teaches a process of inaking an aluminum-zirconium
lzydroxychloride glycinate complex having a pealc 4 to peak 3 pealc height
ratio of 0.5 to 1.8
and peaks (1+2) contain less than 4% of the total distribution by weight. The
process
involves mixing an aqueous zirconyl hydroxychloride solution with an 8% to 35%
by weight
basic aluminum chloride solution at a temperature of from 500C to 100 C for a
period of time
of less than 2 hours to form a coinbined solution. Zirconium species are
furtlier polymerized
during the heating process, which can not always be demonstrated by SEC-HPLC
profile
depending on the types of size exclusion colunms involved and the experimental
conditions
employed.
U.S. Patent No. 4,900,534 discloses a direct process of making aluminuzn-
zirconium
salt by dissolving aluminum metal in an aqueous solution comprising zirconium
oxychloride
and aluminum chloride at about 50 C to 105 C. The solution of the final
aluminum-
zirconium chlorohydrate has a concentration of metal of 0.5 to 2.3 moles/Kg
and a SEC-
HPLC Band III of at least 20%. The high temperature treatment polymerizes the
zirconium
species substantially, which results in the loss of effectiveness of the
antiperspirant.
EU0653203 Al teaches an improved process for inaking novel zirconium salts
which
involves mixing zirconium starting material and glycine at ambient temperature
and
3
CA 02586725 2007-04-26
WO 2006/046945 PCT/US2004/035006
combining said zirconium/glycine aqueous mixture witli an aluminum
chlorohydrate starting
material then rapidly drying the resultant aluminum
chlorohydrate/glycine/zirconium
mixture. There is no disclosure related to the effect of Cl/Zr ratios of the
zirconium solutions
and the concentrations of the aluminum chlorohydrate solutions on the
polymerization of the
zirconium species, which are generally accepted as crucial to the efficacy of
aluminum-
zirconium antiperspirant.
U.S. Patent No. 6,375,937 B1 describes aii aluminum-zirconium chlorohydrate
composition witli low metals to chloride ratio of from 0.9 to 1.2 and a
glycine to zirconium
molar ratio greater than 1.3. The active salt can be prepared by three
different methods; the
mixing of zirconyl chloride with activated ACH salt is one of the disclosed
methods. The
ratio of glycine to zirconium of the said composition is greater than 1.30.
U.S. Patent No. 6,436,381 B1 discloses enhanced efficacy aluminum-zirconium
antiperspirant compositions having SEC-HPLC pealc 5 of about 33% or more and
an SEC-
HPLC peak 4 to pealc 3 area ratio of at least 0.4. The salt compositioiis have
a low metal to
chloride ratio of about 0.9 to about 1.0, which when applied can give rise to
skin irritation.
The enhanced efficacy of aluminum-zirconium antiperspirant salts is generally
achieved through the activation of aluminum species and the extent of the
activation is
characterized by different methods sucli as SEC-HPLC, 27A1 NMR and Ferron
analysis.
These metliods mostly characterize the aluminum species. There is very little
information
generally available about the nature and extent of polymerization of the
zirconium species in
antiperspirant salts. There are limited methods available for the
characterization of zirconium
species that restricts the understanding of the zirconium chemistry that
contributes to the
eiilianced efficacy of aluminum-zirconium antiperspirant salts.
It would be highly desirable to provide aluminum-zirconium antiperspirant
salts
having increased efficacy comprising both activated aluminum species and
depolymerized
zirconium coinplexes. Such aluminum-zirconium antiperspirant compositions will
provide
higher efficacy than the conventional prior art salts heretofore described
under the same
conditions, such as Al to Zr ratio and metal to chloride ratio content.
SUMMARY OF THE INVENTION
According to the present invention an Inductively Coupled Plasma (ICP)
instrument is
applied to characterize the extent of the polymerization of zirconium species
of activated
aluminum-zirconium antiperspirant salts. The zirconium species are first
separated by Size
4
CA 02586725 2007-04-26
WO 2006/046945 PCT/US2004/035006
Exclusion Chromatography (SEC) operated via a High Performance Liquid
Chromatograh
(HPLC). It was discovered that after SEC-HPLC separation, analysis by ICP
revealed a good
correlation between the intensity of the zirconium pealc at retention time of
about 4.3 minutes
to 4.9 minutes and the extent of the polymerization of the zirconium species,
i.e., the higher
the intensity of the zirconium species, the greater their degree of
polymerization.
The extent of polymerization of the zirconium species in an activated aluminum-
zirconium salt is affected by several factors such as (a) the ratio of
cliloride to zirconium in a
zirconium hydroxy chloride (ZHC) solution; (b) the heat treatment of ZHC
glycinate
solution; and (c) the concentration of the activated basic aluminum chloride
(BAC) solution.
By carefully controlling the reaction conditions, a novel aluminum-zirconium
antiperspirant
salt of enhanced efficacy is obtained, comprising activated aluminum and
depolymerized
zirconium species. Specifically, the activated aluminum-zirconium salt of this
invention is
prepared by (1) heating a solution of about 15% to 25%, preferably 18% to 22%,
by weight,
BAC solution having an aluminum to chloride ratio of about 1.5 to about 2.1,
preferably fiom
about 1.8 to about 2.0, at a temperature of at least 50 C, preferably higher,
for a period of
time sufficient to yield the desired activation; (2) blending a concentrated
ZHC glycinate
solution that has been heated at a temperature of greater than 50 C with the
heated BAC
solution at RT, and (3) drying the blended final solution to a powder.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is the SEC-HPLC of ZHC solution with Cl/Zr ratio of 1.05.
Fig. 2 is the SEC-HPLC of ZHC solution with Cl/Zr ratio of 1.27.
Fig. 3 is the SEC-HPLC of ZHC solution with Cl/Zr ratio of 1.53.
Fig. 4 is the ICP-SEC-HPLC of ZHC solution with Cl/Zr ratio of 1.05.
Fig. 5 is the ICP-SEC-HPLC of ZHC solution with Cl/Zr ratio of 1.27.
Fig. 6 is the ICP-SEC-HPLC of ZHC solution with Cl/Zr ratio of 1.53.
Fig. 7 is the SEC-HPLC of ZHC glycinate solution with Cl/Zr ratio of 1.05 at
RT.
Fig. 8 is the SEC-HPLC of ZHC glycinate solution with Cl/Zr ratio of 1.05 at
80 C.
Fig. 9 is the SEC-HPLC of ZHC glycinate solution with Cl/Zr ratio of 1.05 at
reflux.
Fig. 10 is the SEC-HPLC of ZHC glycinate solution with Cl/Zr ratio of 1.53 at
RT.
Fig. 11 is the SEC-HPLC of ZHC glycinate solution with Cl/Zr ratio of 1.53 at
80 C.
Fig. 12 is the SEC-HPLC of ZHC glycinate solution with Cl/Zr ratio of 1.53 at
reflux.
Fig. 13 is the ICP-SEC-HPLC of ZHC glycinate solution with Cl/Zr ratio of 1.05
at
RT.
CA 02586725 2007-04-26
WO 2006/046945 PCT/US2004/035006
Fig. 14 is the ICP-SEC-HPLC of ZHC glycinate solution with Cl/Zr ratio of 1.05
at
80 C.
Fig. 15 is the ICP-SEC-HPLC of ZHC glycinate solution with Cl/Zr ratio of 1.05
at
reflux.
Fig. 16 is the ICP-SEC-HPLC of ZHC glycinate solution with Cl/Zr ratio of 1.53
at
RT.
Fig. 17 is the ICP-SEC-HPLC of ZHC glycinate solution with Cl/Zr ratio of 1.53
at
80 C.
Fig. 18 is the ICP-SEC-HPLC of ZHC glycinate solution with Cl/Zr ratio of 1.53
at
reflux.
Fig. 19 is the ICP-SEC-HPLC of activated Al-Zr powder with M/Cl ratio of 1.13
and
with ZHC glycinate solution made at RT .
Fig. 20 is the ICP-SEC-HPLC of activated Al-Zr powder with M/Cl ratio of 1.25
where ZHC glycinate solution was forined at RT.
Fig. 21 is the ICP-SEC-HPLC of activated Al-Zr powder with M/Cl ratio of 1.25
where ZHC glycinate solution was formed at 80 C.
Fig. 22 is the SEC-HPLC of activated Al-Zr powder with M/Cl ratio of 1.25
where
ZHC glycinate solution was formed at RT.
Fig. 23 is the SEC-HPLC of activated Al-Zr powder with M/Cl ratio of 1.25
where
ZHC glycinate solution was formed at 80 C.
Fig. 24 is the 27A1 NMR of activated AI-Zr powder according to Experiment 8 in
Exainple 2 (Table II).
DETAILED DESCRIPTION OF THE INVENTION
The present invention describes enhanced efficacy aluminum-zirconium
antiperspirant salt compositions comprising activated aluminum and
depolymerized
zirconium species. The compositions have a SEC-HPLC Band III to II area ratio
of at least
0.5, preferably at least 0.7 and nlost preferably at least 0.9, which are
achieved by the heating
of 15% to 25% by weight basic aluminum salts having the formula
Al2(OH)6_aXa
wherein X is Cl, Br, I or NO3, a is from about 1 to about 1.4, with basic
aluminum chloride
solution the most preferred. It is preferable to have a BAC solution with
aluminum to
chloride ratio of about 1.3 to about 2.1 and most preferably froin about 1.6
to about 2Ø The
time of the heating depends on the teinperatures, as longer times are usually
required at lower
6
CA 02586725 2007-04-26
WO 2006/046945 PCT/US2004/035006
temperatures and shorter times at higher temperatures. It is preferred to heat
the diluted BAC
solutions at 50 C, preferably at 80 C and most preferably at reflux for at
least 2 hours. The
concentration of the BAC solutions has a large effect on the extent of the
polymerization of
the zirconium species in the activated aluminum-zirconium antiperspirant salt.
It was
observed that zirconium species polymerized furtlier at lower BAC
concentrations. In order
to achieve the increased efficacy of the combined salt, it is preferable to
have about 15% to
about 25% by weight BAC solutions and most preferably about 18% to about 22%
by weight
of BAC solutions.
Zirconium compounds useful in the present invention have the formula
ZrO(OH)bX2-b
wlierein b is a numerical number from 0 to 1.2, X is Cl, Br, I or NO3, with
chloride being the
most preferred. The zirconiuin hydroxychloride solution can be prepared by the
reaction of
basic zirconium carbonate with hydrochloric acid or zirconyl chloride at
elevated temperature
for a certain period of time. It has been found that there is not a
substantial difference in the
polymerization of the zirconium species in ZHC solution prepared by the above
two different
methods, especially at higher chloride to zirconium ratio. The conditions of
the preparation
such as the preparation temperature, heating time and the concentration of the
ZHC solutions
have greater effects on the polymerization of zirconium species. The
polymerization of the
zirconium species is largely controlled by the chloride to zirconium (Cl/Zr)
ratio of the ZHC
solutions, i.e., the higher the Cl/Zr ratio the more the depolymerized the
zirconium species. It
is desirable to have ZHC solutions with Cl/Zr ratio of at least 1, preferably
of at least 1.4, and
more preferably of at least 1.6. The ZHC solutions are further mixed with an
amino acid,
preferably glycine, at a temperature of about 50 C, preferably at about 80 C
to reflux, for a
period of about 1 liour to about 4 hours. It has been observed that the
heating of the ZHC
glycinate solutions has a very substantial effect on the degree of
polymerization of the
zirconium species in the final aluminum-zirconium antiperspirant salt,
especially at higher
Cl/Zr ratio. Heating the ZHC glycinate solution at 80 C for 1 hour for
example, greatly
depolymerized the zirconium species, sometimes to a greater extent, even at
lower Cl/Zr
ratios, than mixing the higher Cl/Zr ratio ZHC glycinate solution at RT.
The amino acids that may be used include glycine, alanine, lysine, ornithine,
citrulline, hydroxyproline, cysteine, threonine, valine, serine, methionine,
glutamic acid and
the mixtures thereof. Glycine is the most preferred amino acid. The quantity
of glycine is
controlled such that the glycine to zirconium molar ratio is of about 1.
7
CA 02586725 2007-04-26
WO 2006/046945 PCT/US2004/035006
The aluminum-zirconium solution is prepared by mixing the activated BAC
solution
with heat treated ZHC glycinate solution at RT for a certain period of time
generally no more
than 1 hour and the final solution is dried to a powder by any appropriate
means, including
freeze-drying and vacuum drying. Spray drying is the most preferred method.
The aluminum-zirconium salts thus prepared have a M/Cl ratio of more than 1,
and
most preferably at least 1.2. Aluminum-zirconium antiperspirant salts with
veiy low M/Cl
ratios of 1 or less generally have iuicreased efficacy. However, these salts
are very difficult to
forinulate. The difficulties include fragrance stability, yellow color and
softness of the sticlc
when these salts are used. They can also be irritating to skin. The aluminum-
zirconium salts
according to the present patent having a M/Cl ratio of 1.2 or above
demonstrate increased
efficacy from both activated aluminum and depolymerized zirconiuin species,
are easy to
formulate and generally more mild to the skin.
The characterization of aluminuin and zirconium species in aluminum-zirconium
antiperspirant salts are determined by the following methods:
SEC-HPLC
The degree of the polymerization of aluminum complexes is determined by Size
Exclusion Chromatography (SEC) operated via a High Performance Liquid
Chromatograph
(HPLC) instrument. In this technique, the highest molecular weight Al species
are eluted first
and are designated as Band I or otherwise called pealcs 1 and 2. Band II (or
peak 3) and Band
III (or pealc 4) are due to intermediate molecular weight Al complexes. Band
IV or peak 5 is
due to the lowest molecular weight Al complexes, including monomers and
diinmers. The
relative area of one or more peaks is determined in order to characterize the
distribution of
polymeric species in aluminum complexes formed. The aluminum-zirconium
antiperspirant
salts of the present invention have SEC-HPLC Band III to Band II area ratio of
at least 0.5,
preferably at least 0.7, and most preferably at least 0.9.
A Phenominex column and a Waters column connected in series (dual coluinn) are
used to obtain a SEC-HPLC Cliromatogram. Each sample is dissolved in deionized
water to
form a 2% by weight Al solution. Each sample is filtered through a 0.45
filter and
chromatographed within 15 minutes using a 0.01N nitric acid solution as the
mobile phase.
Nuclear Magnetic Resonance Spectroscopy
27A1 Nuclear Magnetic Resonance (NMR) is utilized to identify the structures
of
different aluminum species in the activated aluminum-zirconium antiperspirant
salts of
enhanced efficacy. The antiperspirant salt in solution form is measured as is
and the powder
8
CA 02586725 2007-04-26
WO 2006/046945 PCT/US2004/035006
is dissolved in deuteriated water to form a 10% by weight solution just before
the
measurement. Data were collected using a Varian Inova 400 instrument at 104.2
MHz.
Generally a sharp peak at chemical shift of about 0 ppm by 27A1 NMR indicates
the
presence of monomeric octahedral Al species. A sharp peak at about 63 ppm fiom
a
tetrahedral aluminum species, indicates the presence A113 species which
contains one
tetrahedral Al center. The other 12 octahedral Al centers in this coinpound
have pealcs that
are too broad to be detected. A broad chemical shift at about 72 ppm is also
from tetrahedral
aluminum species and indicates the presence of A141 species. Larger aluminum
species
usually show chemical shifts that are too broad to be detected. The aluminum-
zirconium
antiperspirant salts of enhanced efficacy comprising activated aluminuzn and
depolymerized
zirconium species according to the present invention do not show sharp peaks
at about 63
ppm.
Inductively Coupled Plasma Spectroscopy (ICP) SEC-HPLC
The present invention employs ICP-SEC-HPLC aiialysis to study the
polymerization
of zirconium species and the distribution of the aluminum polymers. The size
exclusion
column operated by HPLC has been used to separate the aluminum and zirconium
polyiners
by size. The separated species are sent to the ICP instead of a refractive
index (RI) detector
as in regular HPLC. Prior to the analysis, the colum.n was conditioned by
repeated injections
of a 10% aluminum-zirconium tetrachlorohydrex glycine solution until the area
of Band I is
constant. The SEC-HPLC data for aluminum-zirconium salt obtained by using RI
detector
are sometimes found to be misleading with respect to the distribution of
zirconiuin species as
can be seen from Figs. 20 to 23. This is because firstly the RI detector is
not very sensitive to
the zirconium species of aluminum-zirconium antiperspirant salts and secondly
the zirconium
pealc(s) at retention times between 4.3 minutes to 4.9 minutes overlap witll
the aluminuin
pealcs Band I and Band II, especially when activated aluminum-zirconium salts
are involved.
When the separated species from the SEC column are detected by ICP, discrete
zirconium
and aluminum peaks are observed. Furthermore, the intensity of the zirconium
peak(s) at
retention times of 4.3 to 4.9 minutes changes with the apparent extent of
polyinerization of
the zirconium species.
The invention will be further illustrated by the following Examples. In the
Examples,
parts are by weight unless otherwise specified.
9
CA 02586725 2007-04-26
WO 2006/046945 PCT/US2004/035006
Example 1: Comparison of Basic Aluininum Cliloride Solutions Prepared by both
Direct
and Indirect Methods
There are two methods for the preparation of the activated basic aluminum
chloride
solution. The first is a direct process, which includes the direct reaction of
aluminum powder
with aluminutn chloride solution at elevated temperature. The second is an
indirect process,
which involves heating a diluted BAC solution at above 50 C for a certain
period of time,
preferably at reflux for about 4 hours. The following solutions are made by
both the direct
and indirect processes and their properties are listed in Table I.
Table I
Experiment Process Al/Cl Ratio Concentration Ferron analysis
Number %w/w %Alb
1 direct 1.88 25% 41.0
2 direct 1.78 25% 29.6
3 indirect 1.75 25% 3.8
4 Indirect 1.90 25% 6.8
The data indicate that there is a different distribution of aluminum species
in the
diluted BAC solutions when made by either the direct and indirect process. The
activated
BAC solution made from the direct process contains more Alb species that is
not considered
to be efficacious as an antiperspirant. It is preferable to make a solution
having a
concentration of about 15% to 25% by weight solution of activated BAC through
the indirect
process.
Example 2: Zirconium Hydroxy Chloride Solutions with Different Chloride to
Zirconium
Ratios
Three ZHC solutions were made by dissolving basic zirconium carbonate paste in
aqueous zirconyl chloride solutions at about 60 C until clear. The ZHC
solutions have
zirconium contents of about 20% with Cl/Zr ratio of 1.53, 1.27 and 1.05,
respectively. The
SEC-HPLC profiles of the three ZHC solutions are illustrated in Figs.1, 2 and
3 with
zirconium species eluted at retention time(s) of about 4.5-4.9 minutes and
chloride at about
7.5 minutes. The solutions were also analyzed by ICP-SEC-HPLC and the
chromatograms
are shown in Figs. 4, 5 and 6. Both SEC-HPLC and ICP-SEC-HPC indicate that the
degree
of polymerization of zirconium species increases with the basicity of ZHC
solutions as
measured by the refractive index of SEC-HPLC and the intensity of the
concentration of
zirconium species of ICP-SEC-HPLC.
CA 02586725 2007-04-26
WO 2006/046945 PCT/US2004/035006
Example 3: Comparison of Zirconium Hydroxy Chloride Glycinate Solutions Heated
Versus Unheated
The ZHC solutions with Cl/Zr ratios of 1.53, 1.27 and 1.05 prepared above were
mixed with glycine at glycine to zirconium molar ratio of about l. The ZHC
glycinate
solutions were then mixed at RT for 2 hours, 80 C for an hour and refluxed for
2 hours,
respectively. The solutions were subjected to both SEC-HPLC and ICP-SEC-HPLC.
Some
of the chromatographs are illustrated in Figs. 7 through 18. The data indicate
that zirconium
species become depolymerized upon addition of glycine and the depolymerization
of the.
zirconium species is more effective at higher temperature such as at 80 C and
reflux as
suggested by ICP-SEC-HPLC, which is not observed by SEC-HPLC especially at
higher
Cl/Zr ratio. At lower Cl/Zr ratio such as about 1, the addition of glycine
does not
depolymerize the zirconium species substantially, both at RT and higher
temperatures.
Example 4: Effect of the Concentration of BAC Solutions on the Polymerization
of
Zirconium Species in the Activated Al-Zr Salts
Six activated aluminum-zirconium antiperspirant powders were made by mixing
ZHC
(Cl/Zr, 1.37) glycinate solutions with six activated BAC solutions (Al/Cl,
1.8) at different
concentrations of 10%, 15%, 18%, 20%, 22% and 25% by weight, respectively. All
six
solutions were treated with the same small quantity of hydrochloric acid, then
spray dried to
give six corresponding powders. SEC-HPLC, 27Al NMR and ICP-SEC-HPLC were
performed on the powders and the results are as follows:
Table II
Experiment %BAC by SEC-HPLC Al NMR Intensity of
Number weight %@Oppm Zr(RT-4.5 min.) by
%I III/II IPC-SEC-HPLC
10 1.9 3.9 11.0 -1070
6 15 1.6 2.2 14.3 -960
7 18 2.4 1.6 14.6 -950
8 20 2.2 1.3 17.3 -870
9 22 0 1.0 12.4 -600
25 1.9 0.8 14.8 -1110
Example 5: Effects of M/Cl Ratio and Heat Treatnient of ZHC Glycinate
Solutions on the
Polymerization of Zirconium Species of the Activated Al-Zr Antiperspirant
Salts
Four activated Al-Zr antiperspirant powders were prepared with M/Cl ratios of
1.13,
1.25, 1.35 and 1.44 and Al/Zr ratio of about 3.3. These were made by treating
about 25% by
11
CA 02586725 2007-04-26
WO 2006/046945 PCT/US2004/035006
weiglit activated BAC solutions with zirconyl chloride glycinate solution and
ZHC glycinate
solutions at Cl/Zr ratios of 1.61, 1.27 and 1.05, respectively, followed by
spray drying.
A-iiother sample was also made similar to the powder with M/Cl ratio of 1.25
except that the
ZHC glycinate solution was heated at 80 C for 1 hour. The SEC-HPLC and ICP-SEC-
HPLC
data are summarized in Table III.
Table III
Experiment M/Cl Ratio ZHC-glycinate SEC-HPLC Intensity of Zr
Number solution (RT-4.5 min.) by
%I III/II IPC-SEC-HPLC
11 1.13 RT 0 0.9 -115
12 1.25 RT 0 0.7 -430
13 1.36 RT 0 0.5 -920
14 1.44 RT 3.9 0.4 -1830
15 1.25 80 C/lhour 0 0.7 -165
ICP-SEC-HPLC and SEC-HPLC profiles of the activated Al-Zr AP powders at M/Cl
ratios of 1.13 and 1.25 from ZHC glycinate solutions formed at botlz RT and 80
C are
illustrated in Figs. 19 through 23. The data further support that zirconium
species
depolymerize at lower M/Cl ratios such as 1.13 and that a similar extent of
depolymerization
of the zirconium species can be achieved at higher M/Cl ratios such as 1.25 by
the heat
treatment of ZHC glycinate solutions. The ICP-SEC-HPLC data also indicate that
the SEC-
HPLC Bands I, II and III can be misleading with respect to the concentration
of aluminuin
species.
The present invention may be embodied in other specific forms without
departing
from the spirit of essential attributes thereof and, accordingly, reference
should be made to
the appended claims, rather than to the foregoing specifications as indicating
the scope of the
invention.
12
