Colour separation films
Quality
Unless otherwise specified, the core density shall be at least 3,5 above the transmission density of the clear film (film base plus fog). The transmission density in the centre of a clear half-tone dot shall not be more than 0,1 above the corresponding value of a large clear area. The transmission density of the clear film shall not be higher than 0,15. Both measurements shall be made with a (UV) transmission densitometer whose spectral products conform to ISO type 1 printing density as defined in ISO 5-3. The fringe width shall not be greater than one fortieth of the screen width; the half-tone dot shall not be split up in distinct parts. The colour separation film quality shall be evaluated according to ISO 12647-1:1996, annex B.
NOTE 1 The clear film density requirement is based on the understanding