Developer compositions for lithographic plates

Claim 1

A method for preparing a photographic element which comprises imagewise light exposing a photographic element comprising a light sensitive negative working photographic composition which composition comprises a photosensitizer selected from the group consisting of a light sensitive diazo compound and a photopolymerizable composition which is disposed on a substrate and then removing the unexposed, non-image areas of said exposed element with an aqueous developer consisting essentially of, in admixture: (a) from above 4.6% to about 27% by weight of α-hydroxy toluene; and (b) from about 0.1% to about 30% of a C 12 sodium alkyl ether sulfate; wherein the weight ratio of components a to b ranges from about 0.9-1.5:1; said developer having a vapor pressure of not more than about 0.15 mm Hg at 25° C. and a flash point of at least about 220° F. and said developer being capable of substantially completely removing said non-image areas in about 2 minutes or less while simultaneously removing substantially none of the exposed image areas; and substantially none of the material comprising said removed non-image areas is re-deposited back onto said photographic element.

Claim 2

A method for preparing a photographic element which comprises imagewise light exposing a photographic element comprising a light sensitive negative working photographic composition which composition comprises a photosensitizer selected from the group consisting of a light sensitive diazo compound and a photopolymerizable composition which is disposed on a substrate and then removing the unexposed, non-image areas of said exposed element with an aqueous developer consisting essentially of, in admixture: (a) from above 4.6% to about 27% by weight of α-hydroxy toluene; and (b) from about 0.1% to about 30% of a C 12 sodium alkyl ether sulfate; wherein the weight ratio of components a to b ranges from about 0.9-1.5:1; said developer having a vapor pressure of not more than about 0.15 mm Hg at 25° C. and a flash point of at least about 220° F. and said developer being capable of substantially completely removing said non-image areas in about 2 minutes or less while simultaneously removing substantially none of the exposed image areas; and substantially none of the material comprising said removed non-image areas is re-deposited back onto said photographic element.