Cold, anodized surfaces

[Paul.Jorden at eev.com]

Posted to CCD-world:
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Jim et al,
 >
 >  Colored anodizing was explained to me 15 yrs ago as follows: creation of 
a
 > honeycomb on the surface, *filling it with dye*, then capping it to hold
 > the dye in.  The dye is not perfectly held in by the cap.  When the 
system
 > is under vacuum but not yet cold, isn't the dye likely to migrate to 
places
 > you don't want it?
 >
As you say, any dye would be undesirable!  Also, even if no dye is used, the 
anodising is a wet process, and in general it is unlikely that the material 
is cleaned well afterwards, bearing in mind the porosity.

Paul
_______________________________________________________________
Dr Paul Jorden,  CCD Applications, EEV
Waterhouse Lane, Chelmsford, Essex, CM1 2QU, UK
Tel:      44 (0) 1245 -453458 (direct), -493493 (switchboard)
Fax:      44 (0) 1245 453224
see also:-     http://www.ccd.eev.com/

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