Method of Making a Flexographic Printing Plate

A method of making a photocured structure by three-dimensional printing, wherein the photocured structure comprises a backing layer for coupling to a relief image printing plate, said method comprising:

• a) providing a liquid photocurable composition in a reservoir of a three-dimensional printer, wherein the liquid photocurable composition comprises:
• i) a binder resin
• ii) monomers;
• and
• iii) photoinitiator;
• and
• b) providing a carrier plate comprising a substrate, wherein the substrate provides a surface on which the photocured backing layer is formed;
• and
• c) using the three-dimensional printer to print liquid photocurable composition onto the substrate while exposing the printed photocurable composition to actinic radiation to cure the printed photocurable composition and form the photocured structure,
• wherein the photocured backing layer comprises solid regions and a lattice structure that mirror printing features of the relief image printing plate mountable thereon,
• wherein durometer and density of the photocured backing layer and shape, size, placement, and density of openings of the lattice structure are controlled to adjust properties of compressibility, modulus, and displaceability.

A method of making a photocured structure by continuous liquid interphase printing, wherein the photocured structure is a backing layer for coupling to a relief image printing plate and is mountable on a printing cylinder, the method comprising the steps of:

• a) providing a liquid photocurable composition in a reservoir, wherein the photocurable composition comprises:
• i) one or more binder resins;
• ii) one or more monomers;
• and
• iii) a photoinitiator;
• wherein a source of actinic radiation is used to selectively crosslink and cure the photocurable composition, the reservoir comprises a bottom which is substantially transparent to the wavelength(s) of actinic radiation used to cure the photocurable composition, and wherein the source(s) of actinic radiation is(are) positioned to shine actinic radiation through the transparent bottom of the reservoir;
• and
• b) providing a carrier plate comprising a substrate wherein the substrate provides a surface on which the photocured backing layer is formed, and wherein the reservoir is below the carrier plate;
• c) bringing the substrate into contact with the liquid photocurable composition in the reservoir:
• d) selectively exposing, the liquid photocurable composition to actinic radiation beneath the transparent bottom of the reservoir, wherein the actinic, radiation crosslinks and cures selected areas of the liquid photocurable composition in the reservoir;
• e) moving the carrier plate away from the reservoir while the actinic radiation continuously crosslinks and cures the photocurable composition to form the photocured backing layer on the carrier plate simultaneously as the carrier plate is withdrawn from the reservoir;
• wherein the photocured backing layer comprises a plate surface structure and a plurality of plurality of protrusions, wherein the photocured backing layer is coupled to a relief image printing plate such that the plate surface structure is in contact with the relief image printing plate and the plurality of protrusions engage a surface of the printing cylinder when the photocured backing layer and relief image printing plate are mounted thereon;
• wherein the shape, number and diameter of the plurality of protrusions are varied as a function of position across a width of the backing layer.