Patent ID: 6346360
Filing Date: 2002-02-12
Classification: G03C,G21K,Y10S

Abstract:
Radiographic film material comprising a transparent film support having first and second major surfaces coated, apart from a subbing layer and, optionally, a non-light sensitive hydrophilic layer thereupon, with at least one light-sensitive silver halide emulsion layer overcoated with a protective antistress layer, said emulsion layer(s) having chemically and spectrally sensitized {111} tabular hexagonal core-shell emulsion grains or crystals in an amount of at least 50% of the total projective grain surface of all grains, said grains being composed of a silver bromide core and a silver bromoiodide shell having an average amount over the whole crystal volume of more than 90 mole % of silver bromide, said grains further having a mean equivalent volume diameter of from 0.3 &mgr;m up to 1.0 &mgr;m and an average grain thickness of less than 0.30 &mgr;m, wherein said film material is coated with a total amount of silver, expressed as an equivalent amount of silver nitrate of less than 7 g/m2, characterized in that all silver iodide is present in an outermost shell corresponding with at most 20% of all silver halide precipitated in order to provide silver iodide to be present in the whole grain volume of said tabular grains in an average amount of less than 1 mole % of iodide, based on silver and in that at least said protective antistress layer comprises a mercapto-tetrazole compound according to the general formula (I), wherein R represents a substituted or unsubstituted alkyl, aryl or aralkyl and wherein M represents a hydrogen atom, an alkali metal atom or an ammonium group, in an amount of at least 0.5 mmole per mole of silver halide coated.