Blueprints

I've been asked about blueprints (again) and would like to
get any new information which is available.  I know that
blueprints are made with an "acidic" process, and that their
color depends on the pH staying to the acid side of neutral.
So we would not alkalize a blueprint.  But has anyone
experimented with encapsulating blueprints, and enclosing an
alkaline buffered sheet at the back of the paper?  Does this
cause any trouble?  Does it have any benefits?

I would be interested in comments based on theory or real
life experiences.  Thanks.

Cathy Atwood

                                  ***
                  Conservation DistList Instance 7:13
                 Distributed: Wednesday, July 21, 1993
                        Message Id: cdl-7-13-007
                                  ***