Hi Mike,
For over 25 yrs. we have demonstrated that it is indeed possible to safely & thoroughly clean Diamond Discs with a water-based blend of ionic & non-ionic surfactants when used as directed. Users include individuals & institutions nationally & internationally, some of whom are members of this list.
Household soaps & detergents are not thorough cleaners of disc phonograph recordings even with a simple rinse. Trace residues can act as feedstock for biological growth & interfere with accurate playback.
Regards,
Duane Goldman
On Apr 24, 2012, at 5:08 PM, Michael Biel wrote:
> From: Roger Kulp <[log in to unmask]>
>> Could someone tell me why the surfaces of so many Diamond Discs seem
>> to flake and peel off,leaving the core exposed? Roger
>
> This was a problem in the earlier years because the surfaces were a
> celluloid sheet laid on a wood-flour core. The wood-flour core would
> absorb water which is why Edison discs must NEVER be washed. The rims
> start to spread and separate, and the celluloid will curl. The three
> dimples in the label area were supposed to help keep the celluloid layer
> secure, and they continued to have the dimples in later years when the
> top surface was changed to a liquid called Condensite which hardened
> with the pressure of the press with pressing times between 20 and 40
> minutes. The core material became changed to clay which did not absorb
> water. This started during the war years when quality materials were
> scarce, and the surfaces were not quiet for several years. It was
> finally when they started using the paper labels in the early 20s that
> the disc surfaces became quieter.
>
> Mike Biel [log in to unmask]
H D Goldman Lagniappe Chemicals Ltd.
PO Box 37066 St. Louis, MO 63141 USA
v/f 314 205 1388 [log in to unmask]
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