A printing plate includes a plurality of relief areas which stand proud of a floor of the plate, each of the relief areas having an uppermost surface to which, in use, is applied a liquid which is borne by the uppermost surface and subsequently contactingly transferred to a substrate material. A predetermined pattern of depressions define a corresponding pattern of islands within the uppermost surface. The depressions within the uppermost surface include at least primary depressions of a first size and substantially geometric first cross-sectional shape, and secondary depressions, being of smaller cross-sectional area than the primary depressions and having a second cross-sectional shape which is distinctly more elongate than the first cross-sectional shape.

Provided is a method for manufacturing a sleeve printing plate capable of forming an image pattern which applies printing on an object to be printed by laser engraving without generating cracks and chippings in a printing plate made of a photosensitive resin. The method for manufacturing a sleeve printing plate by making a printing plate made of a photosensitive resin surround an outer peripheral surface of a circular cylindrical sleeve body and forming an image pattern on the printing plate by laser engraving includes the steps of: washing and cooling the printing plate with water; applying heating treatment to the printing plate at a predetermined temperature; and applying heat radiation treatment to the printing plate after the heating treatment.

Provided is a method for manufacturing a sleeve printing plate capable of forming an image pattern which applies printing on an object to be printed by laser engraving without generating cracks and chippings in a printing plate made of a photosensitive resin. The method for manufacturing a sleeve printing plate by making a printing plate made of a photosensitive resin surround an outer peripheral surface of a circular cylindrical sleeve body and forming an image pattern on the printing plate by laser engraving includes the steps of: washing and cooling the printing plate with water; applying heating treatment to the printing plate at a predetermined temperature; and applying heat radiation treatment to the printing plate after the heating treatment.

The present disclosure provides a printing plate capable of stably suppressing occurrence of a marginal phenomenon. The printing plate includes a printing projection portion having a plurality of projections formed in a distributed manner on a top surface of the printing projection portion, wherein the top surface of the printing projection portion includes a center region and a peripheral edge region adjacent to a peripheral edge of the center region, wherein the peripheral edge region includes printing direction portions extending along a printing direction and perpendicular direction portions extending along a perpendicular direction perpendicular to the printing direction, wherein distribution densities of the projections are different among the center region, the printing direction portions, and the perpendicular direction portions, and wherein, among the distribution densities, a distribution density in the perpendicular direction portions is highest, and a distribution density in the printing direction portions is lowest.

A relief printing original plate for rotary letterpress printing wherein at least an adhesive layer, a photosensitive resin layer and a cover film are successively layered on a support, wherein the photosensitive resin layer contains at least a synthetic rubber-based polymer, a photopolymerizable unsaturated compound and a photopolymerization initiator, and Shore A hardness of a surface of the photosensitive resin layer after photo-curing is 80 to 95. Preferably, the synthetic rubber-based polymer is a hydrophobic polymer obtained from a water-dispersible latex having a weight-average gelation degree of 50 to 80%. Preferably, the photosensitive resin layer contains 20 to 70% by mass of the synthetic rubber-based polymer. The relief printing original plate is suitably used for a rotary printing machine of a center drum type.

A relief printing original plate for rotary letterpress printing wherein at least an adhesive layer, a photosensitive resin layer and a cover film are successively layered on a support, wherein the photosensitive resin layer contains at least a synthetic rubber-based polymer, a photopolymerizable unsaturated compound and a photopolymerization initiator, and Shore A hardness of a surface of the photosensitive resin layer after photo-curing is 80 to 95. Preferably, the synthetic rubber-based polymer is a hydrophobic polymer obtained from a water-dispersible latex having a weight-average gelation degree of 50 to 80%. Preferably, the photosensitive resin layer contains 20 to 70% by mass of the synthetic rubber-based polymer. The relief printing original plate is suitably used for a rotary printing machine of a center drum type.

A method includes (i) preparing a printing original plate sheet having an uncured photosensitive resin layer on a surface thereof, wherein compressive strength of the uncured photosensitive resin layer at 25 C. is 1.0 to 3.0 kgf/cm.sup.2; (ii) mounting the printing original plate sheet around a cylindrical support in such a manner that a starting terminal of the mounting and an ending terminal of the mounting are overlapped; and (iii) applying pressure to the overlapped area of the starting terminal of the mounting and the ending terminal of the mounting at a temperature range of 10 to 40 C. so as to pressure-bond the overlapped area. The method may further include, after the step (iii), a step (iv) for photo-curing the uncured photosensitive resin layer and may further comprise, after the step (iv), a step (v) for grinding, abrading and/or machining the overlapped area.

A method includes (i) preparing a printing original plate sheet having an uncured photosensitive resin layer on a surface thereof, wherein compressive strength of the uncured photosensitive resin layer at 25 C. is 1.0 to 3.0 kgf/cm.sup.2; (ii) mounting the printing original plate sheet around a cylindrical support in such a manner that a starting terminal of the mounting and an ending terminal of the mounting are overlapped; and (iii) applying pressure to the overlapped area of the starting terminal of the mounting and the ending terminal of the mounting at a temperature range of 10 to 40 C. so as to pressure-bond the overlapped area. The method may further include, after the step (iii), a step (iv) for photo-curing the uncured photosensitive resin layer and may further comprise, after the step (iv), a step (v) for grinding, abrading and/or machining the overlapped area.

A flexographic printing plate includes at least one halftone printing area with a plurality of halftone dots. A halftone dot of said plurality of halftone dots is shaped as a relief area. Said relief area includes a central portion and a surrounding portion. Said central portion has a central dot floor with a first pattern of a plurality of pins protruding upwardly from the central dot floor. Said surrounding portion protrudes upwardly from the central dot floor and has a top side including a second pattern of a plurality of recesses. The first pattern and second pattern are such that the surrounding portion can be distinguished from the central portion.

The invention pertains to a printing form and a process for preparing a polymeric printing form from a curable composition that includes a multifunctional urethane in a specified reactive group equivalent weight range, and an initiator. The process includes coating the curable composition onto a supporting substrate, such as a print cylinder, to form a layer, curing the layer with heat or by exposure to actinic radiation, and engraving the resulting cured layer to form at least one printing cell in the cured layer. The process prepares novel polymeric printing forms, particularly novel polymeric gravure printing forms, having a cured polymer-based composition layer that is engravable, resistant to solvent inks, and capable of printing gravure-quality images. The present invention shortens the time to prepare gravure printing cylinders and removes the need for and disposal of toxic heavy metals such as copper and chrome associated with conventional gravure print cylinder preparation.