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.

Provided is to provide a cylindrical printing plate with which printing of excellent solid density and high halftone dot quality is made possible, and further print medium followability and printing durability are excellent, a cylindrical printing plate precursor, a method for manufacturing a cylindrical printing plate precursor, and a method for manufacturing a cylindrical printing plate. A cylindrical printing plate includes a relief layer having a first hard layer, a soft layer, and a second hard layer in this order from a printing surface side, in which a hardness K1 of the first hard layer is 10 MPa or more and less than 20 MPa, a ratio K1/K2 of the hardness K1 of the first hard layer with respect to a hardness K2 of the soft layer is 2.7 or more, a ratio K3/K2 of a hardness K3 of the second hard layer with respect to the hardness K2 of the soft layer is 1.2 or more, a thickness of the first hard layer is 0.05 mm or more and 0.3 mm or less, and a thickness of the soft layer is 0.3 mm or more and 2.0 mm or less.

Provided is to provide a cylindrical printing plate with which printing of excellent solid density and high halftone dot quality is made possible, and further print medium followability and printing durability are excellent, a cylindrical printing plate precursor, a method for manufacturing a cylindrical printing plate precursor, and a method for manufacturing a cylindrical printing plate. A cylindrical printing plate includes a relief layer having a first hard layer, a soft layer, and a second hard layer in this order from a printing surface side, in which a hardness K1 of the first hard layer is 10 MPa or more and less than 20 MPa, a ratio K1/K2 of the hardness K1 of the first hard layer with respect to a hardness K2 of the soft layer is 2.7 or more, a ratio K3/K2 of a hardness K3 of the second hard layer with respect to the hardness K2 of the soft layer is 1.2 or more, a thickness of the first hard layer is 0.05 mm or more and 0.3 mm or less, and a thickness of the soft layer is 0.3 mm or more and 2.0 mm or less.

Provided are an offset printing plate, an offset printing apparatus, and an offset printing method, which are capable of printing a high-definition image by waterless offset printing.

The offset printing plate comprises: a cylindrical plate base material; a silicon resin layer formed on the cylindrical plate base material; and a resist pattern part formed on the silicon resin layer, in which the silicon resin layer serves as a non-printing area, and the resist pattern part serves as a printing area. The silicon resin layer is preferably formed on the cylindrical plate base material seamlessly.

Provided are an offset printing plate, an offset printing apparatus, and an offset printing method, which are capable of printing a high-definition image by waterless offset printing.

The offset printing plate comprises: a cylindrical plate base material; a silicon resin layer formed on the cylindrical plate base material; and a resist pattern part formed on the silicon resin layer, in which the silicon resin layer serves as a non-printing area, and the resist pattern part serves as a printing area. The silicon resin layer is preferably formed on the cylindrical plate base material seamlessly.

Lithographic printing plate precursors are prepared with a unique substrate and one or more radiation-sensitive imageable layers. The substrate is prepared by two separate anodizing processes to provide an inner aluminum oxide layer having an average dry thickness (T.sub.i) of 650-3,000 nm and a multiplicity of inner micropores having an average inner micropore diameter (D.sub.i) of 15 nm. A formed outer aluminum oxide layer comprises a multiplicity of outer micropores having an average outer micropore diameter (D.sub.o) of 15-30 nm; an average dry thickness (T.sub.o) of 130-650 nm; and a micropore density (C.sub.o) of 500-3,000 micropores/m.sup.2. The ratio of D.sub.o to D.sub.i is greater than 1.1:1, and D.sub.o in nanometers and the outer aluminum oxide layer micropore density (C.sub.o) in micropores/m.sup.2, are further defined by the outer aluminum oxide layer porosity (P.sub.o) according to the following equation:

0.3P.sub.o0.8

where P.sub.o is 3.14(C.sub.o)(D.sub.o.sup.2)/4,000,000.

An object of the present invention is to provide a flexographic printing plate having excellent ink transferability in a solid portion and the like and having good printing quality in a halftone portion. The flexographic printing plate of the present invention is a flexographic printing plate having a relief layer including a non-image area and an image area, in which the image area has a halftone dot portion having a halftone dot area ratio of more than 0% and less than 100%, and a solid portion having a halftone dot area ratio of 100%, small dots in the halftone dot portion and the solid portion or small dots in the halftone dot portion have two or more recessed portions having different depths according to a halftone dot area ratio, and the two or more recessed portions having different depths are recessed portions whose depth becomes deeper as the halftone dot area ratio increases.

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.

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.

The present invention is to provide a flexographic printing plate having high ink transferability and making it possible to perform printing with a high ink density in a solid portion, a flexographic printing plate precursor, a method for manufacturing a flexographic printing plate, and a method for manufacturing a flexographic printing plate precursor. A flexographic printing plate of the present invention includes a relief layer including a non-image area and an image area having an uneven structure formed on a surface, in which the uneven structure is composed of recessed portions consisting of a plurality of grooves and projecting portions other than recessed portions, each of the plurality of grooves has a length of at least 30 m, all of the plurality of grooves are grooves having a line edge roughness in a range of 0.5 to 2.5 m in a region of 30 m of the groove in a longitudinal direction, a depth of the recessed portion is 5 to 25 m, and a ratio of the projecting portion is 5% to 60% of a geometric area of the uneven structure.