Method for making a broadband reflective laser recording and data storage medium with absorptive underlayer

A negative photographic process for making a reflective optical data storage medium comprising

• areawise exposing a silver-halide emulsion photosensitive medium to a uniform non-saturating level of actinic radiation,
• developing the exposed silver halide of said exposed medium to low-reflective, filamentary gray silver, while leaving both exposed, developed gray silver and unexposed, undeveloped silver halide in place,
• forming a layer of silver precipitating nuclei at sites of undeveloped silver halide at the surface of the gray medium,
• dissolving unexposed silver halide in said medium to form soluble silver ion complexes, while leaving developed gray silver in place,
• transporting by silver diffusion transfer soluble silver ion complexes to said precipitating nuclei and said developed filamentary silver and
• reducing and precipitating said soluble silver complexes to reflective metallic silver at said nuclei and said developed filamentary silver in a reflective metallic layer of primarily non-filamentary silver less than one micron thick over a low-reflective gray layer of primarily filamentary silver.

A negative photographic process for making a reflective optical data storage medium comprising

• areawise exposing a silver-halide emulsion photosensitive medium to a moderate exposure of actinic radiation through a mask having at least two levels of optical density to the actinic radiation, where said mask is disposed between the source of said actinic radiation and said photosensitive medium,
• exposing the entire silver-halide photosensitive emulsion to a weak to moderate exposure of actinic radiation,
• developing said exposed emulsion to create low-reflective, gray filamentary silver, while leaving both exposed, developed gray silver and unexposed, undeveloped silver halide in place,
• nucleating a surface layer of unexposed silver halide in said developed medium, whereby silver precipitating nuclei are created in said surface layer, and
• contacting said nucleated emulsion with a monobath comprising a silverhalide solvent and a silver reducing agent, leaving developed gray silver in place, whereby unexposed and undeveloped silver halide forms soluble silver ion complexes and is transported by diffusion transfer to said nuclei where silver is reduced to reflective metallic silver on said nuclei and to said filamentary silver where silver is reduced to metallic silver on said filamentary silver thereby forming a reflective metallic layer of primarily non-filamentary silver over a low-reflective gray layer of primarily filamentary silver.