| 摘要 |
PURPOSE:To prevent generation of loose winding of the title light shielding paper by regulating the flexibility of the light shielding paper to 10-40g. CONSTITUTION:In light shielding paper coated with a resin on one or both sides of a base paper to be used for the light shielding package of a roll shaped photosensitive material, light shielding paper for packing the roll shaped photosensitive material having rigidity corresponding to 10-40g flexibility is used. The flexibility is measured by prepg. a circle having complete roundness of 25mm diameter from a strip of light shielding paper having 20mm breadth, bonding the strip at both ends superposed by 3mm on each other with a double coated adhesive tape, pushing the bonded tape with 40mm/min velocity from a diagonal direction after charging the tape in a load cell, and observing a repulsive force exerted on the load cell when the diameter of the test piece attains 1/2. Preferred thickness of the paper to be used for the base is 60-95mum, and preferred amount of the resin to be coated on the base paper is 10-50mum. By this constitution, generation of loose winding in the stage of operating a camera is prevented. |
