Disclosed herein are methods for an ink-based digital printing system, comprising providing an imaging member a reimageable surface layer disposed on a structural mounting layer, the reimageable surface layer comprising a fluorosilicone elastomer and an infrared-absorbing filler comprising carbon black, and a plurality of surface defects on the reimageable surface layer, wherein the surface defects comprises carbon black exposed through the fluorosilicone elastomer of the reimageable surface layer. The method also comprises applying a coating of rejuvenating oil comprising an amino-functional organopolysiloxane to the reimageable surface layer, whereby at least a portion of the plurality of surface defects are coated by the amino-functional organopolysiloxane, thereby rejuvenating the imaging member.

A negative type photosensitive resin composition includes a polymer compound which contains a linking group represented by Formula A-1 in a main chain and an ethylenically unsaturated group; and a polymerization initiator. In Formula A-1, R.sup.1 and R.sup.2 each independently represent a hydrogen atom or a monovalent organic group, and X.sup.1 represents a linking group represented by any of Formulae A-2 to A-6.

A negative type planographic printing plate precursor includes an image recording layer containing the negative type photosensitive resin composition.

A method of preparing a planographic printing plate includes, in order, an exposure step of image-exposing the negative type planographic printing plate precursor; and a development step of performing development by removing a non-exposed portion of the exposed negative type planographic printing plate precursor using a developer.

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A lithographic printing plate precursor has a substrate comprising a hydrophilic surface and two opposing edges; a radiation-sensitive imagable layer, and optionally, a protective layer disposed over that layer. The precursor has a shear droop at each opposing edge, each shear droop having a shear droop depth Y of 20-200 m and a shear droop width X of 500-2000 m. The precursor also has a hydrophilic coating band extending from each of the two opposing edges inwardly along the hydrophilic surface independently to provide a hydrophilic coating band width A of at least 1.5 times the shear droop width X. This hydrophilic coating band comprises amphoteric surfactant(s) in an amount greater than all other surfactants. Such individual precursors are obtained by cutting a continuous radiation-sensitive web into strips and such cutting creates the shear droop that can result in edge staining if the hydrophilic coating band is not present.

A negative type photosensitive resin composition includes a polymer compound which has, in a main chain thereof, a constitutional unit A represented by Formula A-1, a constitutional unit B that is at least one of constitutional units represented by Formulae B-1, B-2, B-3, B-4, B-5, B-6, or B-7, and a constitutional unit C containing an ethylenically unsaturated group; and a polymerization initiator.

A negative type planographic printing plate precursor includes an image recording layer containing the negative type photosensitive resin composition.

A method of preparing a planographic printing plate includes, in order, an exposure step of image-exposing the negative type planographic printing plate precursor; and a development step of performing development by removing a non-exposed portion of the exposed negative type planographic printing plate precursor using a developer.

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An on-press development type lithographic printing plate precursor includes a support and an image-recording layer on the support. The image-recording layer contains a polymerization initiator, an infrared absorber, a color forming substance precursor, and an auxiliary capable of donating an electron to the infrared absorber. A polymer having an ethylenically unsaturated group and a water-soluble monofunctional monomer are present on a surface of the support on an image-recording layer side, a layer in contact with the support on the image-recording layer side contains the polymer having an ethylenically unsaturated group and the water-soluble monofunctional monomer, or a layer in contact with the support on the image-recording layer side, other than the image-recording layer, contains the polymer having an ethylenically unsaturated group and the image-recording layer contains the water-soluble monofunctional monomer.

A method of making a lithographic printing plate includes the steps of a) image-wise exposing a lithographic printing plate precursor including a hydrophilic support and a coating containing a colorant precursor to form a lithographic image consisting of printing areas and non-printing areas, b) developing the plate precursor to remove the coating in the non-printing areas from the support, and c) drying the plate precursor, and d) subjecting the plate precursor to heat or radiation to induce a colour change of the coating in the printing areas, wherein before step b) the coating in the non-printing areas and the support are characterised by a CIE 1976 colour difference E.sub.1 which is 5.0 or less, and after step d) the CIE 1976 colour difference E.sub.2 between the coating in the printing areas and the non-printing areas is more than 6.8.

A lithographic printing sleeve for mounting on a cylinder in a printing press is provided. The lithographic printing sleeve includes a tubular base layer for contacting and surrounding an outer circumference of the cylinder, a permanent tubular hydrophilic layer on an outer surface of the tubular base layer and a temporary hydrophobic layer on an outer surface of the tubular hydrophilic layer. A variable cutoff printing press is also provided.

An on-press development type lithographic printing plate precursor, including an image-recording layer on a support, in which the image-recording layer contains an infrared absorber A, a borate compound B, an iodonium compound C, and a color forming substance precursor D, and a surface free energy of an outermost layer on an image-recording layer side is 115 mJ/m.sup.2 or less, and a method of preparing a lithographic printing plate, a lithographic printing method, and a laminate using the on-press development type lithographic printing plate precursor.

An apparatus comprises: (a) a rotatable drum configured to have a UV-curable printing plate with an ablatable layer thereon, placed thereon; (b) at least one laser beam to image the plate on the drum by ablating some of the ablatable layer according to image data to form an imaged plate; (c) an unloading area onto which a plate is movable when unloaded; and (d) a plurality of UV LEDs configured to apply UV radiation to the back of the UV-curable plate or to both the front and back of the UV-curable plate during or after the unloading of the imaged plate.

Disclosed herein are methods for an ink-based digital printing system, comprising providing an imaging member a reimageable surface layer disposed on a structural mounting layer, the reimageable surface layer comprising a fluorosilicone elastomer and an infrared-absorbing filler comprising carbon black, and a plurality of surface defects on the reimageable surface layer, wherein the surface defects comprises carbon black exposed through the fluorosilicone elastomer of the reimageable surface layer. The method also comprises applying a coating of rejuvenating oil comprising an amino-functional organopolysiloxane to the reimageable surface layer, whereby at least a portion of the plurality of surface defects are coated by the amino-functional organopolysiloxane, thereby rejuvenating the imaging member.