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Richard: This is an increasingly common problem with a number of video tapes as well. If, in past postings, you have seen me mention "binder-base adhesion failure"- this is what we have been calling the phenomena for the last few decades. We have seen the problem for a number of years but, recently, there has been a frightening increase in the number of instances where it is occurring with VHS, 3/4" and 2" video. We have seen it in a number of audio tapes, but it appears to be more prevalent with older video. One of the first times we saw this problem was over 20 years ago with a large number of 2" instrumentation tapes that had been stored in a Quonset hut in the South Pacific. We have done some testing and tracked down the history on a variety of tapes that have shown the problem in the past. From our research, we have come up with a few scenarios that seem to impact how often BBAF will occur. Similar to what Tom speculated, many tapes with BBAF were stored in areas where one could expect frequent and very extreme shifts in temperature, humidity or both. Testing of some tapes clearly shows that the base layer and the recording layer expand and contract at different rates with changes in either temperature or humidity. If the tapes are frequently exposed to extreme shifts in climate, it is logical to speculate that repeated stresses could weaken the bond between the two layers. We have also, but not always, found that this effect is linked with tapes that are showing some degree of binder hydrolysis. One interesting observation is that this phenomena is quite common on tapes that have cinched and folded back upon themselves in the wrap. If the tape is stored with the cinch for an extended time, BBAF will frequently occur where the oxide layer from two adjacent wraps is touching. When the tape is straightened out, the recording surfaces that were touching simply fall off the tape in a sheet. Frequently, BBAF is not a problem on the rest of the tape. Final comment- we developed a procedure to deal with binder-base adhesion failure about 10 or 15 years ago. Unfortunately, the procedure takes a few months and is only successful about 60% of the time. With the work in tape restoration and recovery we have done over the last 23 years, we consider binder-base adhesion failure to be a much more serious, though less frequent, decay problem than binder hydrolysis. Peter Brothers President SPECS BROS., LLC (973)777-5055 www.specsbros.com Restoration and Disaster Recovery Service Since 1983 > -----Original Message----- > From: Association for Recorded Sound Discussion List > [mailto:[log in to unmask]]On Behalf Of Richard L. Hess > Sent: Friday, March 31, 2006 11:01 PM > To: [log in to unmask] > Subject: [ARSCLIST] Delaminating tape article > > > I thought you good folks would enjoy the latest adventure in cassette > purgatory. DELAMINATION. > > I invite your comments. > > http://richardhess.com/notes/2006/03/31/project-notes-advanced-oxi de-delamination-of-a-cassette/ Is this what we can expect in years to come? Any idea of the cause? Benoit? Bill? Hopefully this is a one-off. Cheers??? Richard Tape Restoration Seminar: MAY 9-12, 2006; details at Web site. Richard L. Hess email: [log in to unmask] Aurora, Ontario, Canada (905) 713 6733 1-877-TAPE-FIX Detailed contact information: http://www.richardhess.com/tape/contact.htm