Arizona sun., 1947-03-07
Process Stops
Cotton Mildew
Bare Discovery of World
Wide Interest Made by
Army Scientists.

nouncement of worldwide interest,
the Philadelphia quartermaster de-
pot revealed it had found way to
protect cotton fabrics from mildeW
by making the fabric fire-resist-
ant. The army further disclosed
that laboratory scientists now be.
ieve that cotton fabrics may simul-
taneously be made capable Of resist
ing fire. water, mildew, sunlight,
shrinkage and possibility of abra-
Sion."
The scientific work here. which is
being studied by cotton interests in
all parts Of the world. also has con-
vinced the developers of the new
methods that equally successful re-
suits can be expected soon for wool. "
The experiments began as a war
time project to fight the enormous
losses in army equipment by quick
rotting of cotton fabrics in the hot,
humid climate of the South Pacific.
This effort was concentrated on
developing fungicides-poisons-to
kill the fungus growths and bacteria
that were doing the damage. Losses
were decreased, but the scientists
found that some fungi fed on the
protective coatings, exposing the
cellulose (basic chemical substance
of the cotton fiber) to attack by 9TH
er varieties of fungi.
Process Traced.
In addition, some of the poisons
were lost through laundering, leach
ing by rain and wear, and others in
jured the human skin or weakened
the fabric itself.
The field of attack accordingly
shifted and research team led by
DR.. Ralph G. H. Stu was created
here for thorough study.
Scientific missions to all parts Of
the world collected samples of fun
gus growth. BY isolation and elm
ination, attention was directed to
about 10000 different cultures.
They learned that fungi enter a
cotton fiber by burrowing from the
outside to the center of the fiber,
then spreading through the fiber
lengthwise and finally growing out
ward toward the surface.
Chemically, the important fact was
that the fungi secreted an engine,
cellulose, which converts into sugar
the cellulose in the cotton. The fun
gi feeds on the sugar but cannot do
SO without the engine.
Four methods of attack then were
considered:
First. ''of considerable PROMISE"
is coating the fabric with resin,
which keeps the fungi out of the fab
ric.
Second, partially successful" use
of a fungicide or poison.
Revolutionary Theory.
Third, Significant theoretical
basis" of the work, inhibit the chem
ical action of the engine and pre-
vent it from converting cellulose into
sugar. This was sweeping idea,
since no one poison will kill all fun
gi but all fungi employ the same
engine.
Fourth, most promising" of all,
change the shape of the cellulose
molecule in the cotton fiber and
thereby prevent the engine from at
taching itself to the cellulose mole
cule at all, meaning no sugar for the
fungi.
In the study of this last approach,
it was learned that if the engine is
to be effective in attacking the cellu-
lose rnolecule, it must match the
shape of that molecule, at least in
certain regions.
Several chemical processes were
found which could effectively change
the shape Of the cellulose molecule
enough to defeat the engine.
Then came the decisive discovery
that precisely this effect also was
created by treatments given to the
fabric for the purpose of making
garments fire-resistant and water
repellant.
There is every reason to be-
lieve," Dr. Stu said, 'that the quar-
termaster corps will have this prob
lem licked before long"