Several years ago, Sheldahl and another company in MN area evaluated Al 
flexible circuits (I previously worked at Sheldahl). These were simple 
circuits, such as a musical Hallmark card and a microwave oven pad 
(throwaway). The contact at Sheldahl who should recall the work and 
closely follows vavuum metallized circuitry is Richard Swisher 507-663-8000.
Sheldahl presently has the ability to make aluminum circuitry but 
equipment is geared to web-fed flexible substrate. They may possibly 
still be making aluminum laminate material for capacitive keyboards that 
could be bonded to rigid substrate.

On Wed, 26 Apr 1995, Crawford, John A. wrote:

> 
> The EMPF HelpLine has received a request to locate a source of specialty 
> circuit boards.  Ultimate use of the assembly will be as a environmental 
> sensor.  The base board material (epoxy glass has been used in the past) is 
> "coated" with a contiguous aluminum through whatever process, nominal 
> thickness approx. .027" or thicker if possible.  The aluminum is then 
> patterned through some subtractive process (chemical or mechanical).  Other 
> processes will ultimately be accomplished to the board, but initial need is 
> to find someone who can do this part of the process. End item is proprietary 
> and patent pending at present and non-disclosure documents will be required.
> 
> Respond either through this TechNet, or e-mail to 
> [log in to unmask], phone 317.26.5616 fax 317.26.5615.
> 
>