A ‘transparent’ high moisture & oxygen barrier film for use with RP sachets
Escal™ for the protection of cultural properties supplied in single sheet rolls or double sheet tube rolls. The material is a ceramic deposited super barrier film developed especially for use with the Mitsubishi RP System (p67). The user can unroll and cut the Escal™ film to a desired length and seal with a heat sealer. Each Escal™ film roll includes a continuous data entry space with a white writable background.
Escal™ has an outstanding ability to keep out moist air. It is therefore very useful not only for the preservation of damp wooden artefacts, but also for all other conservation or storage purposes. On the other hand, the RP agent works to keep the inside atmosphere of a container very dry, therefore it is not appropriate for conservation or storage of small quantities of paper/textile materials or wooden artefacts, which require a more normal pH.
Mitsubishi have developed another type called RP-K which does not affect the moisture in a container and which therefore can be used for non-metallic artefacts. This product is mainly used to protect photographs, films and dyed products from discolouring and fading. It also prevents mildew and insect damage to paper, textile materials and wooden artefacts.
Using Escal™ and the RP System
Metal artifacts and many museum objects can be perfectly protected from retrogradation by removing oxygen and moisture content with RP Type A oxygen and moisture scavengers.
RP Type K is moisture neutral and will not remove moisture from the enclosure. However the moisture barrier created by the Escal™ or PTS enclosure ensures a stable microclimate for the enclosed object.
This means that the period during which the quality of these artifacts can be preserved depends on the correlation between the barrier performance (oxygen permeability and moisture permeabiity) of the film and the enclosed amount of RP Agent.
The barrier film should have a particularly good gas barrier performance in both oxygen and moisture permeabilities.