Give and Take

From: Nicholas Bodley (nbodley@world.std.com)
Date: Wed Mar 28 2001 - 13:01:48 PST


Woops! Critical omission! The liquid crystal material is encapsulated
into tiny transparent capsules by what has to be an interesting
process; look into something invented a few decades ago by National
Cash Register and their NCR (TM) paper, still used for multipart
carbonless* forms. They were able to encapsulate all sorts of
materials to create what seemed to be a powder.

(How are glass microballoons made?)

Three kinds of liquid crystal: Cholesteric, smectic, and nematic.
(Courtesy of a very informative ad in Scientific American, decades
ago, likely by Kodak/Eastman chemicals, research labs...)

NCR = No Carbon (paper) Required, also,

When I was an electronic tech., I used a sheet of encapsulated l.c.
to find overheating components (often, solid tantalum capacitors
installed backwards) on newly-manufactured circuit boards. I'd apply
low power, and watch; hot air rising would create a spot. Temp. range
was just above a comfortable room ambient.

Nicholas Bodley |@| Waltham, Mass.
Please reply to nbodley@alumni.princeton.edu
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Autodidact and polymath to some extent



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