Bookbinding and the Conservation of Books
A Dictionary of Descriptive Terminology

laminating film

The "ideal" laminating film should: 1) be flexible, i.e., capable of withstanding all the flexing and folding that is required of the paper being protected throughout the useful life of the document; 2) be (considerably) stronger than the paper it protects. (Since the majority of papers found in archival collections exhibit an elongation of about 2% upon rupture, the film should offer satisfactory strength at an elongation of less than 2% to protect the document, and should also have sufficient strength to make reinforcement with tissue unnecessary); 3) have considerable elongation beyond the yield point of a stress-strain curve. (Because high edge tearing resistance is usually associated with high elongation, a narrow margin of film around the edges of a document would protect it in case of strain at the edges); 4) have properties enabling it to resist degradation; 5) be capable of being joined to the document with minimum effort, preferably without application of heat and pressure; 6) permit separation of the film from the paper with minimum effort and without damage to the document; 7) be resistant to abrasion; 8) be transparent to light, at least throughout the visible spectrum; and 9) contain no elements or other substances which might in any way damage the document it protects. (303 , 364 )