This is a very good summary:-:-
Preserving Old Photos and Documents
but also:-
WARNING!:
Archivists have discovered the hard way that using ordinary lamination plastic for old documents, newspapers, photos, etc., does not preserve them. The best way to preserve them is to store them in a dark place after placing in acid-free Mylar film (not laminated). Ordinary lamination material still permits light rays to pass through it and to cause a chemical reaction to the acid that most modern paper and modern dyes contain, and that ALL old documents photos contain. This causes deterioration of paper and fading of the paper and print. The heat and pressure of most lamination processes also damages documents.
Of course, keeping original documents is important, but one should always copy (scan) newspapers and other documents and then print them on acid free paper, which can be found at just about all stores selling printer paper and/or computer supplies. Too, one should save the graphics files from scanned documents and put the files on CDs for permanent safekeeping. Life expectancy for data on CDs is 80-100 years for premium quality CDs.