The present invention provides a pattern forming method of forming a plurality of pattern layers on a substrate by using a plurality of lithography apparatuses including a first lithography apparatus and a second lithography apparatus, the method comprising a first step of forming a first pattern layer by the first lithography apparatus which adopts a die-by-die alignment method, based on alignment information obtained by using the die-by-die alignment method for a plurality of marks formed on the substrate by a lithography apparatus which adopts a global alignment method, and a second step of forming a second pattern layer so as to overlap with the first pattern layer by the second lithography apparatus, based on alignment information obtained by using the global alignment method for a plurality of shot regions formed on the substrate by the first lithography apparatus in the first step.

The present invention aims at providing a lithographic printing plate precursor, a lithographic printing plate manufacturing method, a printing method and an aluminum support manufacturing method that enable the resulting lithographic printing plate to have a long tiny dot press life. The lithographic printing plate precursor of the invention is a lithographic printing plate precursor having an aluminum support and an image recording layer disposed above the aluminum support. When measured over a 400 m400 m region of a surface of the aluminum support on the image recording layer side using a three-dimensional non-contact roughness tester, pits with a depth from centerline of at least 0.70 m are present at a density of at least 3,000 pits/mm.sup.2; and a surface area ratio S is not less than 35%, the surface area ratio S being determined using an actual area S.sub.x obtained, through three-point approximation, from three-dimensional data acquired by measurement at 512512 points in 25 m square of the surface of the aluminum support on the image recording layer side by means of an atomic force microscope and a geometrically measured area S.sub.o.

The present invention provides a lithographic printing plate precursor that enables a lithographic printing plate formed therefrom to have excellent image visibility and a long press life, as well as a lithographic printing plate manufacturing method and a printing method. The lithographic printing plate precursor of the invention is a lithographic printing plate precursor including an aluminum support and an image recording layer, the aluminum support includes an aluminum plate and an anodized film of aluminum formed on the aluminum plate, the anodized film is positioned closer to the image recording layer than the aluminum plate is, the anodized film has micropores extending in a depth direction of the anodized film from a surface of the anodized film on the image recording layer, the micropores have an average diameter of more than 10 nm but not more than 100 nm at the surface of the anodized film, and the surface of the anodized film on the image recording layer side has a lightness L* of 70 to 100 in a L*a*b* color system.

The present invention provides a lithographic printing plate precursor that enables a lithographic printing plate formed therefrom to have excellent image visibility and a long press life, as well as a lithographic printing plate manufacturing method and a printing method. The lithographic printing plate precursor of the invention is a lithographic printing plate precursor including an aluminum support and an image recording layer, the aluminum support includes an aluminum plate and an anodized film of aluminum formed on the aluminum plate, the anodized film is positioned closer to the image recording layer than the aluminum plate is, the anodized film has micropores extending in a depth direction of the anodized film from a surface of the anodized film on the image recording layer, the micropores have an average diameter of more than 10 nm but not more than 100 nm at the surface of the anodized film, and the surface of the anodized film on the image recording layer side has a lightness L* of 70 to 100 in a L*a*b* color system.

There is described a recto-verso printing press (100*) adapted to carry out simultaneous recto-verso printing of sheets, the printing press (100*) comprising a main printing group (5, 6, 15, 16, 25, 26) with first and second printing cylinders (5, 6) cooperating with one another to form a first printing nip between the first and second printing cylinders (5, 6) where first and second sides of sheets are simultaneously printed, the first printing cylinder (5) acting as a sheet conveying cylinder of the main printing group (5, 6, 15, 16, 25, 26). The printing press (100*) further comprises an additional printing group (7, 8, 17, 18, 27, 28) with third and fourth printing cylinders (7, 8) cooperating with one another to form a second printing nip between the third and fourth printing cylinders (7, 8) where the first and second sides of the sheets are simultaneously printed, the third printing cylinder (7) acting as a sheet conveying cylinder of the additional printing group (7, 8, 17, 18, 27, 28). The main printing group (5, 6, 15, 16, 25, 26) and the additional printing group (7, 8, 7, 18, 27, 28) are coupled to one another by means of an intermediate sheet conveying system comprising one or more sheet-transfer cylinders (10, 10, 10)interposed between the first and third printing cylinders (5, 7).

There is described a recto-verso printing press (100*) adapted to carry out simultaneous recto-verso printing of sheets, the printing press (100*) comprising a main printing group (5, 6, 15, 16, 25, 26) with first and second printing cylinders (5, 6) cooperating with one another to form a first printing nip between the first and second printing cylinders (5, 6) where first and second sides of sheets are simultaneously printed, the first printing cylinder (5) acting as a sheet conveying cylinder of the main printing group (5, 6, 15, 16, 25, 26). The printing press (100*) further comprises an additional printing group (7, 8, 17, 18, 27, 28) with third and fourth printing cylinders (7, 8) cooperating with one another to form a second printing nip between the third and fourth printing cylinders (7, 8) where the first and second sides of the sheets are simultaneously printed, the third printing cylinder (7) acting as a sheet conveying cylinder of the additional printing group (7, 8, 17, 18, 27, 28). The main printing group (5, 6, 15, 16, 25, 26) and the additional printing group (7, 8, 7, 18, 27, 28) are coupled to one another by means of an intermediate sheet conveying system comprising one or more sheet-transfer cylinders (10, 10, 10)interposed between the first and third printing cylinders (5, 7).

Dry, ablation-type, nitrocellulose-containing lithographic printing members include dual adjacent imaging layers, both including an absorber and at least one containing a binder (which may include or consist essentially of a melamine resin). The absorber of the nitrocellulose-containing layer is a pigment and this layer contains no absorbing dye, while the absorber of the other imaging layer includes or consists essentially of a dye.

Dry, ablation-type, nitrocellulose-containing lithographic printing members include dual adjacent imaging layers, both including an absorber and at least one containing a binder (which may include or consist essentially of a melamine resin). The absorber of the nitrocellulose-containing layer is a pigment and this layer contains no absorbing dye, while the absorber of the other imaging layer includes or consists essentially of a dye.

A cleaning apparatus includes an inker roller and an ink source holding ink for the inker roller. The inker roller contacts a reimageable surface of an imaging member downstream of an ink image transfer station that transfers an ink image from the surface to a print sheet, with the surface having residual ink remaining thereon after the transfer of the ink image. The inker roller applies ink from the ink source against the reimageable surface. However, instead of the ink transferring from the inker roller to the surface, the ink stays with the inker roller and removes the residual ink from the surface to clean the surface for a subsequent ink image. The inker roller is not contaminated from removing the residual ink as the inker roller is designed to be coated by ink that adds to its coating of ink via the removed residual ink.

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.