[at-l] Re: silk vs. cotton

[siler@voyager.net (Paul Haan)]

I think it is helpful to think of silk as wicking fabric rather than an
insulating fabric, thus perhaps explaining the phenomenon experienced with
the wet t-shirt contest (?!?!).

My experience w/ silk has been that it functions very well on hot days,
drying quickly.  I also use it in winter as it is a nice, thin material for
transferring moisture away from my skin.  Yet my winter use *always* uses it
as a base layer with something over it.  It has nice wicking properties,
keeping the skin dry, but not insulating properties.

When I use it alone in the cold (without another layer), it tends to
increase the chill factor.  My hunch is that this is because the weave
increases surface area for wicking and exposure, thus resulting in an
inefficient way to keep the body warm without another layer to help retain
body heat.

My guess is this is what is happening with the wet silk in the swimming
example.  The wet cotton, on the other hand, is probably thick enough that
it does provide some warming qualities in a temperate setting.  I'm not so
sure the results of the cotton would be as great if the temperature was to
drop...not that silk alone would be any better.  If you plan on getting wet,
I think there are probably better fabrics than both silk and cotton.  Not to
say that swimming in a fleece is easy!

IMO, it is important to remember that the purpose of silk is not to
insulate, but to transfer moisture away from the skin.  The transpiration is
probably what keeps one warm is the winter and cool and in the summer.

Siler