On-press developable IR sensitive printing plates using binder resins having polyethylene oxide segments

A polymerizable composition comprising

• a polymerizable compound, and
• between about 10 and about 90 weight percent of a polymeric binder;
• wherein the polymeric binder is selected from the group consisting of at least one graft copolymer comprising a main chain polymer and polyethylene oxide side chains, a block copolymer having at least one polyethylene oxide block and at least one non-polyethylene oxide block, and a combination thereof;
• wherein the polymerizable composition comprises discrete particles of the graft or block copolymer.

A method for preparing a printing plate, the method comprising

• providing a substrate;
• applying a negative-working layer comprising a radiation sensitive composition onto the substrate, wherein the radiation sensitive composition comprises a polymerizable compound and a polymeric binder, wherein the polymeric binder is selected from the group consisting of at least one graft copolymer comprising polyethylene oxide side chains, a block copolymer having at least one polyethylene oxide block, and a combination thereof, and wherein the radiation sensitive composition comprises discrete particles of the graft or block copolymer;
• imagewise exposing the negative-working layer to ultraviolet, visible, or infrared radiation;
• and
• developing the negative-working layer to produce a printing plate.

A method of preparing an imageable element comprising:

• providing a substrate;
• and
• coating onto the substrate a radiation sensitive composition, the radiation sensitive composition comprising a polymerizable compound, a radiation absorber and between about 10 and about 90 weight percent of a polymeric binder selected from the group consisting of at least one graft copolymer comprising polyethylene oxide side chains, a block copolymer having at least one polyethylene oxide block, and a combination thereof;
• wherein the radiation sensitive composition comprises discrete particles of the graft block copolymer.