Aerosol product development laboratories are continuing to work
on novel products, as well as modifying existing mainstream ones,
creating flankers and adjusting for regulatory and environmental
concerns—being aware of the many pitfalls can improve the
possibility for commercial success…
An advertisement for The Hot One
Self Heating Shave Cream from
Gillette in the November 1970
edition of Hot Rod magazine.
March 2020 SPRAY 31
cosmetic ingredients list since they had never been used previously. Obtaining
approval would require years of testing, so the project was abandoned.
Over the years, a few aerosol products have entered the market only to be
withdrawn when unanticipated problems became evident. About 1975, chemist
Sam Prussen, consulting for Dart Industries, developed a self-heating aerosol
shave cream and some other related products. The heat was generated when a
6% solution of hydrogen peroxide (H2O2) was mixed with sodium thiosulfate
(Na2SO3). Working with a major valve company, Prussen devised a valve where
the tailpiece dip-tube descended to the bottom of a 0.94" OD (outside diameter)
plastic inner container of H2O2, while a side dip-tube went into the shave cream
and to the bottom of the aerosol can. The valve acted to proportionate the separate
ingredients so that actuations would simultaneously empty both inner and
outer products.
After royalty negotiations, a major aerosol filler produced about 25,000 units
for the Rexall Drug Co. The filling process was extremely slow and costly, due to
filling and attaching the H2O2 tube and hand inserting the valve assembly into
the can. A slight excess of the shave cream phase was needed; a cool product at
the end being preferable to spraying the 6% H2O2 solution. However, the most
vexing problem was the generation of off-odor byproducts by the exothermic reaction,
such as persulfate, dithionic and trithionic structures, producing the mild
but unwanted odor of cooking eggs. Some other shave cream marketers launched
products such as “The Hot One” and “Infernomatic Foam,” but the problems
outweighed the benefits. The innovation disappeared within a year or two.
Around 1970, the food market
was touted as having the greatest
potential for aerosol products. Despite
thousands of hours of developmental
work, that prediction still remains
elusive. The U.S. food aerosol market of close to 500
million units is almost entirely due to only two product
types: whipped cream and cookware lubricant. Some
other countries, such as Brazil and Germany, have food
aerosol markets so small that they go unreported in
surveys. The greatest impediment is the possibility of
microbial contamination.
Over the years, there have been several attempts to
develop aerosol pancake batter. In perhaps the most
sophisticated, a flowable batter was inoculated with
sodium propionate, heated for 10 minutes at about
158°F (70°C), poured into pre-heated aerosol cans,
sealed and gassed with about 2% carbon dioxide. Over
160 microorganisms were added, tested and failed to
proliferate. However, the temperature was critical and
every molecule of the batter had to be heated to that
158°F temperature, which posed a major challenge.
Higher temperatures could not be used or the batter
would begin to “cook” and thicken. Hundreds of filled
cans were successfully stored at room temperatures for
over one year. The batter became slightly less viscous,
due to hormonal activity, but all other attributes (including
appearance and taste) were perfectly normal.
The problems of producing a
self-heating shave cream ultimately
outweighed the benefits.
Despite thousands of hours of developmental
work, the prediction that the food market has
the greatest potential for aerosol product development
still remains elusive. The U.S. food
aerosol market of close to 500 million units is
comprised almost entirely of two product types:
whipped cream and cookware lubricant.