Concertina View larger

Concertina

Concertina envelope, system for the storage of 35, 60 and 70 mm photographic negatives. Single piece die-cut with creases to form 6 pockets.
For the long term storage of the most precious and sensitive photographic archive material, where the utmost caution has to be taken against degradation from contact with potentially harmful elements such as adhesives that may, in time, react with the enclosed material.
Made of unbuffered high purity 100% cotton paper.

Specifications:

- 100% cotton fibre
- pH 6.7
- Unbuffered
- Non satin surface to allow maximum transpiration
- Glue free
- O.B.A.'s free (optical brightening agents)
- Reducible sulphur, as S, mg/kg, (ppm) less than 1
- Low ash content: 0,06%
- P.A.T. Photographic Activity Test (ANSI ISO 18916)
- Silver Tarnish Test
- Long Life ISO 9706 (Permanence Test)

Colour: White

Weight: 80 g/m2
Pack: 25 units