Imaging member containing a copolymer of styrene and ethyl acrylate

An imaging method comprising providing a migration imaging member comprising a substrate and an electrically insulating softenable layer adjacent said substrate, said softenable layer comprising a fracturable layer of electrically photosensitive migration marking material located substantially at or near the surface of said softenable layer spaced from said substrate, and a copolymer of styrene and ethyl acrylate in at one layer adjacent said substrate, said copolymer comprising between about 40 and about 80 mole percent styrene, between about 20 and about 60 mole percent ethyl acrylate, and between about 0 and about 3 mole percent copolymerizable organic acid having carbon-to-carbon unsaturation or copolymerizable derivative thereof, said copolymer having a M.sub.n between about 4,000 and about 35,000, a M.sub.w between about 10,000 and about 80,000, an acid number up to about 25, a T.sub.g between about 30.degree. C. and about 75.degree. C., a melt viscosity between about 1.times.10.sup.2 poise and about 1.times.10.sup.6 poise at 115.degree. C.;

• electrostatically charging said member to deposit a uniform charge on said member;
• exposing said member to activating radiation in an imagewise pattern prior to substantial decay of said uniform charge;
• and developing said member by decreasing the resistance to migration of marking material in depth in said softenable layer at least sufficient to allow migration of marking material whereby marking material migrates toward said substrate in image configuration.

An imaging method comprising providing a substrate and an electrically insulating softenable layer on said substrate, said softenable layer comprising charge transport molecules, said charge transport molecules being capable of increasing charge injection from said electrically photosensitive migration marking material to said softenable layer, being capable of transporting charge to said substrate and being dissolved or molecularly dispersed in said softenable layer a fracturable layer of electrically photosensitive migration marking material located substantially at or near the surface of said softenable layer spaced from said substrate, and a copolymer of styrene and ethyl acrylate at or near the surface of said softenable layer adjacent said substrate, said copolymer comprising between about 40 and about 80 mole percent styrene, between about 20 and about 60 mole percent ethyl acrylate, and between about 0 and about 3 mole percent copolymerizable organic acid having carbon-to-carbon unsaturation or copolymerizable derivative thereof, said copolymer having a M.sub.n between about 10,000 and about 35,000, a M.sub.w between about 25,000 and about 80,000, an acid number up to about 25, a T.sub.g between about 30.degree. C. and about 75.degree. C., a melt viscosity between about 1.times.10.sup.2 poise and about 1.times.10.sup.6 poise at 115.degree. C.;

• exposing said member to activating radiation in an imagewise pattern whereby said electrically photosensitive migration marking material struck by said activating radiation photogenerates charge carriers;
• decreasing the resistance to migration of migration marking material in said softenable layer sufficiently to allow the light-struck migration marking material to retain a small net charge which allows at most slight agglomeration, slight coalescence, slight migration in depth of marking material towards said substrate or combination thereof;
• and further decreasing the resistance to migration of marking material in said softenable layer sufficiently to allow migration marking material which escapes radiation to substantially agglomerate and coalesce.

An imaging method comprising providing a substrate and an electrically insulating softenable layers on said substrate, said softenable layer comprising charge transport molecules, said charge transport molecules being capable of increasing charge injection from said electrically photosensitive migration marking material to said softenable layer, being capable of transporting charge to said substrate and being dissolved or molecularly dispersed in said softenable layer a fracturable layer of electrically photosensitive migration marking material located substantially at or near the surface of said softenable layer spaced from said substrate, and a copolymer of styrene and ethyl acrylate at or near the surface of said softenable layer adjacent said substrate, said copolymer comprising between about 40 and about 80 mole percent styrene, between about 20 and about 60 mole percent ethyl acrylate, and between about 0 and about 3 mole percent copolymerizable organic acid having carbon-to-carbon unsaturation or copolymerizable derivative thereof, said copolymer having a M.sub.n between about 4,000 and about 35,000, a M.sub.w between about 10,000 and about 55,000, an acid number up to about 25, a T.sub.g between about 30.degree. C. and about 75.degree. C., a melt viscosity between about 1.times.10.sup.2 and about 1.times.10.sup.5 poise at 115.degree. C.;

• exposing said member to activating radiation in an imagewise pattern whereby said electrically photosensitive migration marking material struck by said activating radiation photogenerates charge carriers;
• decreasing the resistance to migration of migration marking material in said softenable layer sufficiently to allow migration in depth of migration marking material towards said substrate in image configuration.