A double-sided adhesive flexographic printing plate underlay for use in the manufacture and mounting of flexographic printing plates is provided. The underlay is carrier sheet with a solvent acrylic adhesive stripe-coating provided on both sides thereof. In addition, a siliconized release liner is provided to cover one of the coated sides of the carrier sheet. Both the carrier sheet and the release liner are formed from a glass clear polyethylene terephthalate (PET) and the solvent acrylic adhesive is transparent such that ultraviolent light can readily pass through the underlay. The construction of the underlay is such that it can withstand the washout conditions employed in the manufacture of both liquid and solid photopolymer flexographic printing plates.

An object of the present invention is to provide a flexographic printing plate precursor which has few mask defects, is unlikely to contaminate an apparatus during development, and is capable of obtaining a flexographic printing plate having excellent concave line reproducibility and being unlikely to cause ink entanglement; and a manufacturing method of a flexographic printing plate using the flexographic printing plate precursor. The flexographic printing plate precursor of the present invention is a flexographic printing plate precursor including, at least, in the following order, a support, a photosensitive resin layer, and a heat-sensitive image forming layer, in which the heat-sensitive image forming layer contains a pigment as an infrared absorber and a dye as an ultraviolet absorber, and an optical density of the heat-sensitive image forming layer is 3.0 or more.

An object of the present invention is to provide a flexographic printing plate precursor which has few mask defects, is unlikely to contaminate an apparatus during development, and is capable of obtaining a flexographic printing plate having excellent concave line reproducibility and being unlikely to cause ink entanglement; and a manufacturing method of a flexographic printing plate using the flexographic printing plate precursor. The flexographic printing plate precursor of the present invention is a flexographic printing plate precursor including, at least, in the following order, a support, a photosensitive resin layer, and a heat-sensitive image forming layer, in which the heat-sensitive image forming layer contains a pigment as an infrared absorber and a dye as an ultraviolet absorber, and an optical density of the heat-sensitive image forming layer is 3.0 or more.

A printing machine including a printing plate on a surface of a rotating cylinder, in which the printing plate has a fixed pattern for receiving a toner; a vessel containing the toner, which includes a pigment and a thermoplastic binder, in which the fixed pattern is a permanent pattern in a form of selected portions of an image is disclosed. A plate for use in the printing machine is also disclosed. A printing system is also disclosed.

A printing machine including a printing plate on a surface of a rotating cylinder, in which the printing plate has a fixed pattern for receiving a toner; a vessel containing the toner, which includes a pigment and a thermoplastic binder, in which the fixed pattern is a permanent pattern in a form of selected portions of an image is disclosed. A plate for use in the printing machine is also disclosed. A printing system is also disclosed.

A printing plate unit to be demountably mounted on a printing plate mounting portion of a plate cylinder includes a printing plate and a printing plate coupling member. A length of the printing plate coupling member is larger than a width of the printing plate so that the printing plate coupling member is provided with a projecting portion projecting from the printing plate formed cylindrically in an axial direction. The printing plate unit is fitted to the printing plate mounting portion from one end side, and is demounted from the same one end side by gripping the projecting portion of the printing plate coupling member in a state both end portions of the printing plate formed into a cylindrical shape are coupled to each other by the printing plate coupling member.

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 present disclosure discloses a transfer printing plate assembly, which includes a transfer printing plate for transfer printing of aligning agent, and a printing cylinder for fixing the transfer printing plate. The transfer printing plate includes a first side, a second side opposite to the first side, and a first connection element at each of the first side and the second side. The printing cylinder includes a second connection element for engaging with the first connection element to prevent the transfer printing plate from shrinking in an axial direction of the printing cylinder when the transfer printing plate is fixed to the printing cylinder.

The present disclosure discloses a transfer printing plate assembly, which includes a transfer printing plate for transfer printing of aligning agent, and a printing cylinder for fixing the transfer printing plate. The transfer printing plate includes a first side, a second side opposite to the first side, and a first connection element at each of the first side and the second side. The printing cylinder includes a second connection element for engaging with the first connection element to prevent the transfer printing plate from shrinking in an axial direction of the printing cylinder when the transfer printing plate is fixed to the printing cylinder.

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.