Re: [ARSCLIST] delamination of CDs

[George Brock-Nannestad <pattac@xxxxxxxx>]

From: Patent Tactics, George Brock-Nannestad

Bev Lambert wrote:
> >I am not a preservation scientist or even an knowledgeable audiophile, but an
> >archives conservator charged with the task of researching best practises for
> >digitization of magnetic media.  So, my question may seem naive: is it known
> >whether CDs are laminated with an adhesive?  and if so, is it known which
> >adhesive this is?  It seems to me that a different process. such as heat or
> >pressure lamination would be more appropriate?

----- several persons responded - apparently correctly - that there are no
adhesives used in the lamination process for CDs. However, for the CD-R to be
able to tolerate handling, there has to be adhesion between the various
layers. If the strength in the interface between layers (adhesion) or in the
material internally (cohesion) is not sufficient for the purpose, then the
laminate separates. That could potentially be the case in the phthalocyanine
layer that separates the polycarbonate from the metallization. I have no
reports of such a thing happening, but on the other hand, very few people
have first-hand experience of phthalocyanine as a house building material. I
have myself _unsuccessfully_ tried the Scotch-tape test (using a high-grade
tape) to separate the polycarbonate sheet from the deposits.

Kind regards,


George