Security film
A security film or acetate film (codes: non flam , de sécurité , safety or safety film ) refers to a cinema and photographic film with cellon as a substrate for the light-sensitive photographic emulsion . Cellon is a product made from cellulose acetate . In contrast to the easily inflammable celluloid film , security film is more difficult to ignite.
History and Development
The security film is a further development of the celluloid film made of nitrocellulose , which in turn was a further development of the paper film . In the case of nitrate-based film materials, self-ignition is possible from approx. 38 ° C. The starting material corresponds to gun cotton and is counted among the explosives in Germany . They are still considered an acute threat to photo collections and historical archives today .
In 1908 Agfa and Kodak began producing security films based on cellulose acetate . Assembled was safety film first as a 16 mm film for motion pictures, and later in other Assemblies.
On October 30, 1939, Germany issued an ordinance on security films, which provided that from April 1, 1940 films could only be produced as security films. However, due to the Second World War , this regulation could not be enforced. In Europe, the security film finally caught on on a large scale from around 1952. An unconfirmed agreement in the industry was to only produce security film from January 1, 1951. ISO 543 defines the designation, test methods and labeling of security film.
Modern security film is made from cellulose acetate or PETP polyester.
See also
Web links
- Klaus Kramer: Identifying and rejecting nitrate films
- Cinema technology: drop flaps and picture window guillotines security film in the projection room
Footnotes
- ↑ cf. Explosives Act (SprengG) of April 17, 1986