I believe alcohol is a solvent to the celluloid surface on a Diamond Disc. It's also a solvent to shellac, so it shouldn't be used on the vast majority of "78-rpm" records. Bags Unlimited has a non-alcohol formulation which I've found safe on lacquers and shellac records:
Scroll down to "Groovy® Record Cleaner for 78 rpm Records." I haven't tried this on Diamond Discs, but I would expect it to be fine. You have to be careful using any liquid cleaner on Diamond Discs. If liquid gets into the wood-pulp core, the record can delaminate. Careful application to the celluloid surface with a pump sprayer should be OK.
I hope this helps.
Audio Engineer Emeritus
The Crane School of Music
SUNY at Potsdam, NY 13676
"Great art presupposes the alert mind of the educated listener."
"A true artist doesn't want to be admired, he wants to be believed."
From: Association for Recorded Sound Discussion List [mailto:[log in to unmask]] On Behalf Of David Breneman
Sent: Thursday, May 24, 2018 2:17 PM
To: [log in to unmask]
Subject: [ARSCLIST] Cleaning Diamond Discs with Grain Alcohol
Will ethyl alcohol harm Diamond Discs? I tried cleaning one
recently and it left rub marks on the surface which will not wipe
off. It appears to actually have altered the surface.
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