Abstract: Disclosed is a printing plate material comprising a substrate and a component layer provided thereon, the substrate having a center line average surface roughness Ra of from 0.2 to 1.0 ?m, and an oil-retention volume A2 of from 1 to 10, wherein the center line average surface roughness Ra is obtained from three dimension surface roughness measurement according to JIS-B-0601, and wherein an image is capable of being recorded on the component layer by imagewise exposure of infrared laser.

Abstract: The positive planographic printing plate precursor of the present invention is a precursor comprising (I) a positive recording layer including a water-insoluble and alkali-soluble polymer compound and a light to heat converting agent, on a support having a hydrophilic surface in which a hydrophilic graft polymer chain is present. The precursor may further comprise (II) a lower layer including a water-insoluble and alkali-soluble polymer compound between the recording layer and the support.

Abstract: A lithographic printing plate precursor is disclosed, comprising a metal support having formed thereon an anodic oxide film, and an image-forming layer containing a light-to-heat converting agent, or a light-sensitive layer capable of image-forming with infrared laser exposure provided in this order from the support.

Abstract: There is disclosed a method of processing a light-sensitive material which comprises exposing a light-sensitive material having at least one light-sensitive layer on a support, and subjecting to development by a dipping system or a coating system, and then, peeling at least the light-sensitive layer off by bringing a peeling material into close contact with the light-sensitive material, wherein the peeling material is a material having a liquid-absorbing rate in which a liquid-absorption amount within 0.1 second after getting in contact with a liquid is 60% or more based on a liquid-absorption amount within 0.2 second after the same.

Abstract: A positive heat-sensitive lithographic printing plate comprising an anodically oxidized aluminum support having laminated thereon an undercoating layer containing a polymer having a constituent having an acid radical and a constituent having an onium group, an interlayer containing a water-insoluble and alkali-soluble resin, and a heat-sensitive layer containing a water-insoluble and alkali-soluble resin and an infrared-absorbing dye in this order from the support, and the solubility of the heat-sensitive layer in an alkali aqueous solution increases by heating.

Abstract: The present invention provides a method for printing, comprising the steps of: a) developing an image forming surface of a planographic printing plate; b) after the developing, hydrophilizing a portion of a vicinity of an edge of the image forming surface; c) after the hydrophilizing, adhering ink to the image forming surface; and d) transferring the ink to a printing target.

Abstract: Disclosed is a process of preparing a printing plate from a printing plate material comprising a support, and provided thereon, an image formation layer, the process comprising the steps of fixing the printing plate material onto a fixing member with suction through-holes by suction that evacuates air through the suction through-holes, the surface (rear surface) of the support opposite the image formation layer facing the fixing member, and then imagewise exposing the fixed printing plate material to laser to form an image on image formation portions of the image formation layer, wherein a degree of flatness of the surface on the image formation layer side of the fixed printing plate material is not more than 50 &mgr;m at the image formation portions.

Abstract: Disclosed is a presensitized plate, having an anodized layer and recording layer provided on a support for a lithographic printing plate, wherein the anodized layer is provided by subjecting an aluminum plate to graining and anodizing treatments. The presensitized plate has wide development latitude, makes it difficult for scratch-like non-image portions to be generated and facilitates handling in usual operation.

Abstract: Plate positioning and processing method and apparatus are disclosed. A plate is conveyed in a predetermined first direction so that the plate is in contact with a pair of first positioning pins. The plate is laterally moved contacting with the first positioning pins until reference positions displaced from contacting positions of the plate with the first positioning pins contact with the first positioning pins. A predetermined first processing is applied to the plate. The plate subjected to the first processing is conveyed in a predetermined second direction so that the plate is in contact with a pair of second positioning pins in positions different from the reference positions of front edge of the plate. The plate contacting with the second positioning pins is laterally moved until the same positions as the reference positions contact with the second positioning pins.

Abstract: A lithographic sheet product having a substrate with a roll textured surface covered by a pretreatment layer. The pretreatment layer enhances adhesion of a printing composition to the sheet product and is composed of a polymer selected from the group consisting of polymers of acrylic acid, polymers of methacrylic acid, an organophosphorous polymer and copolymers of an organophosphorous compound and acrylic acid or methacrylic acid. Dopant particles of alumina, silica, titanium dioxide or a black dye or pigment may be added to the pretreatment layer to reduce the gloss and reflectance of the pretreatment layer in a printing process. Etching of the substrate also reduces gloss and reflectance.

Abstract: A planographic printing member precursor comprises a first component, for example a hydroxy group containing polymer, and a second component which may be a siloxane or a compound of general formula (I), wherein M represents a silicon or a titanium atom and each of R1, R2, R3 and R4 is independently selected from hydrogen or halogen atoms; a hydroxy group; an optionally substituted alkyl, alkenyl or alkynyl group; an optionally substituted alkoxy group; or an optionally substituted saturated or unsaturated cyclic or heterocyclic group. On exposure, the second component reacts with the first component to define an oleophobic/hydrophilic material in exposed areas and in non-exposed areas the second component is removed, on processing of the precursor.

Abstract: A lithographic printing plate precursor comprises: a support; and an image-forming layer including a copolymer containing a specific fluoroaliphatic group and a repeating unit corresponding to at least one of a poly(oxyalkylene) acrylate and a poly(oxyalkylene) methacrylate.

Abstract: The present invention relates to a heat mode-compatible planographic printing plate comprising a photosensitive layer which is capable of recording with an infrared laser and formed by applying a photosensitive layer coating solution onto a hydrophilic support and then drying the photosensitive layer coating solution, the photosensitive layer coating solution being obtained by dissolving or dispersing I) an IR absorber, II) a polymerization initiator, and III) a compound having a polymerizable unsaturated group in a solvent, wherein the residual solvent in the photosensitive layer is 5% by weight or less relative to the weight of the photosensitive layer.

Abstract: The present invention discloses a planographic printing plate having a notched portion on its surface having a required size, and having smaller burrs at a rear face, and a planographic printing plate cutting device and a planographic printing plate cutting method for forming such a planographic printing plate by cutting. The planographic printing plate cutting device of the present invention includes an upper roller for forming a recessed section at the planographic printing plate. The upper roller, which is formed substantially into a disc shape as a whole, has a pressing portion parallel to a web (the planographic printing plate), and a slope portion that is slanted with respect to the surface of the web at a predetermined inclination. This upper roller presses the web such that a sloped face (recessed section) that is slanted with respect to the surface of the web is formed. Next, a shearing roller shears the web at the sloped face such that a remaining portion of the sloped face forms a notched portion.

Abstract: A planographic printing plate precursor and its fixing method on a plate cylinder of a printing press are disclosed, the planographic printing plate precursor comprising a flexible substrate and provided thereon, an ink repellent layer or a hydrophilic layer wherein the planographic printing plate precursor has an 830 nm light transmittance of not less than 10%.

Abstract: A lithographic printing precursor for lithographic offset printing comprises, a layer of imageable medium on a hydrophilic base. The imageable medium comprises hydrophobic polymer particles in an aqueous medium, a substance for converting light into heat, and a non-crosslinkable aqueous-soluble composition. The lithographic printing precursor may be used to make lithographic printing surfaces that obtain long run lengths on lower quality paper and in the presence of press-room chemicals. The lithographic printing precursor can be imaged and developed on-press and the imageable medium can also be sprayed onto a hydrophilic surface to create a printing surface that may be processed wholly on-press. It can also be processed in the more conventional fully off-press fashion. The hydrophilic surface can be a printing plate substrate or the printing cylinder of a printing press or a sleeve around the printing cylinder of a printing press. The cylinder can be conventional or seamless.

Abstract: A negative-working heat-sensitive material for making a lithographic printing plate by direct-to-plate recording is disclosed which comprises in the order given a lithographic base having a hydrophilic surface, an oleophilic imaging layer and a cross-linked hydrophilic upper layer, characterize in that the oleophilic imaging layer comprises at least one transition metal complex of an organic acid. Materials according to the invention are characterized by an increased run length and can be used as a printing plate immediately after exposure.

Abstract: A method and apparatus for the electrostatic printing of dry or wet toners using a novel tiered printing plate allows for superior and efficient transfer of toner from the plate to the printed item. The process for producing the printing plate uses photo polymer film resist with a positive photo tool which after developing yields trenches between ridges of hardened photo polymer which hold the toner in desired pattern.

Abstract: A positive photosensitive printing plate is prepared wherein the photosensitivity is to near-infrared rays which do not induce a chemical change in a photosensitive component. The photosensitive material has an inclined structure from the viewpoint of dissolution of the irradiated portion in an alkali developer. The dissolution rate is such that it continuously increases from the upper, surface part of the photosensitive material to the lower part of the photosensitive material. This effect may be enhanced by diffusion of a material, preferably a polar compound, such as H2O, from the surface toward the inner lower part of the photosensitive material. Techniques for accomplishing the diffusion include contacting the surface of the photosensitive material with an atmosphere of high humidity or overlaying the photosensitive material with a layer of protective material (paper) containing moisture and heating the resultant composite.

Abstract: Provided is a heat-sensitive lithographic printing plate comprising a support having thereon an undercoat layer and a heat-sensitive layer in this order, with at least one of the undercoat layer and the heat-sensitive layer comprising polymer hollow microspheres having voids on the inside, or a heat-sensitive lithographic printing plate comprising a support having thereon a heat-sensitive layer, with the heat-sensitive layer comprising polymer hollow microspheres having voids on the inside.

Abstract: A heat-sensitive lithographic printing plate precursor is disclosed, comprising a metal substrate having thereon 1) an ink-receptive layer, 2) a water-receptive layer comprising a colloidal particulate oxide or hydroxide of at least one element selected from the group consisting of beryllium, magnesium, aluminum, silicon, titanium, boron, germanium, tin, zirconium, iron, vanadium, antimony and transition metals, or additionally 3) a water-soluble overcoat layer, at least one layer of the ink-receptive layer, the water-receptive layer and the overcoat layer containing a compound capable of converting light into heat and the ink-receptive layer containing an epoxy resin having a softening point of 120° C. or more.

Abstract: A lithographic printing plate substrate is conditioned for imaging in a printer engine by an edge protector adhered along at least one edge of the plate substrate, the edge protector being of a flexible material, being coextensive with the edge, having face portions adhered to portions of the opposite faces adjacent the edge, and having an edge portion overlying the edge.

Abstract: According to the present invention there is provided a heat-sensitive material for making lithographic plates comprising in the order given on a support an IR-sensitive oleophilic layer and an ablatable cross-linked hydrophilic layer comprising an inorganic pigment and a hardener, characterized in that the ratio of said inorganic pigment over the hardener is comprised between 95/5 and 75/25 by weight.

Abstract: According to the present invention there is provided a heat-sensitive material for making lithographic plates comprising in the order given on a support an IR-sensitive oleophilic layer and a cross-linked hydrophilic layer comprising an inorganic pigment and a hardener, characterized in that the ratio of said inorganic pigment over the hardener is comprised between 75/25 and 25/75 by weight.

Abstract: An imaging member, such as a negative-working printing plate or on-press cylinder, can be prepared with a hydrophilic imaging layer comprised of a heat-sensitive hydrophilic polymer having ionic moieties and an infrared radiation sensitive dye having multiple sulfo groups. The heat-sensitive polymer and IR dye can be formulated in water or water-miscible solvents to provide highly thermal sensitive imaging compositions. In the imaging member, the polymer reacts to provide increased hydrophobicity in areas exposed to energy that provides or generates heat. For example, heat can be supplied by laser irradiation in the IR region of the electromagnetic spectrum. The heat-sensitive polymer is considered “switchable” in response to heat, and provides a lithographic image without wet processing.

Abstract: A photosensitive lithographic printing plate having a photosensitive resin layer formed on an aluminum substrate subjected to electrolytic surface roughening in nitric acid or in an electrolyte composed mainly of nitric acid and further to anodic oxidation treatment, wherein the photosensitive resin layer is made of a photopolymerizable composition comprising (A) an addition-polymerizable ethylenically unsaturated bond-containing monomer, (B) a photopolymerization initiator, and (C) a polymer binder, wherein the addition-polymerizable ethylenically unsaturated bond-containing monomer (A) contains a phosphate compound having at least one (meth)acryloyl group.

Abstract: According to the present invention there is provided a heat sensitive imaging element comprising on a lithographic base with a hydrophilic surface an image forming layer including thermoplastic particles of a homopolymer or a copolymer of styrene and a hydrophilic polymer containing carboxyl groups, characterized in that said imaging element further contains an anionic IR-cyanine dye being present in said image forming layer or a layer adjacent thereto.

Abstract: A printing plate for computer-to plate lithography having a metal substrate with an anodized surface portion. The anodized surface portion has a porous texture in which a radiation-absorbing composition, preferably a black dye, is deposited. The surface portion with the radiation-absorbing composition is covered with a hydrophilic polymer or a sealant both. Upon exposure to laser radiation, the underlying oleophilic anodized surface portion containing the radiation-absorbing composition is revealed. Alternatively, laser radiation of the polymer composition may cause the affinity of the polymer for water and ink to change so that an irradiated portion of the polymer becomes oleophilic while the non-irradiated portion remains hydrophilic.

Abstract: A planographic printing plate and a manufacturing method thereof are provided in which a deterioration in quality and performance of the planographic printing plate due to coating defects caused by foreign matter adhering to a support can be prevented. The planographic printing plate has stable quality such as uniform sensitivity with respect to writing by an infrared ray laser or the like and uniform developability. The planographic printing plate includes a support, a primer layer, and a recording layer superposed in that order. In the manufacturing method, a step of forming the primer layer, in which a coating solution for a primer layer is applied onto the support, is carried out at least two times. At this time, before a coating solution for a previous primer layer has completely dried, a coating solution for a subsequent primer layer is applied. This type of application is preferable in terms of coating uniformity and prevention of an increase in coating thickness.

Abstract: This patent describes on-press ink and/or fountain solution development of lithographic plates having on a substrate a thermosensitive layer capable of hardening or solubilization upon exposure to an infrared laser radiation. The plate can be imagewise exposed with an infrared laser and then on-press developed with ink and/or fountain solution by rotating the plate cylinder and engaging ink and/or fountain solution roller. The developed plate can then directly print images to the receiving sheets. The imagewise exposure can be performed off the press or with the plate being mounted on the plate cylinder of a lithographic press.

Abstract: The present invention provides a planographic printing plate capable of ensuring improvement of productivity and stability of a small dot net portion due to improvement of adhesion. There is provided a planographic printing plate, characterized in that a surface of an aluminum plate being a support element of the planographic printing plate has been subjected to preliminarily polishing mechanically by at least 0.1 &mgr;m; chemical etching treatment by at least 0.1 &mgr;m; electrochemically surface-roughening; and anodic oxidation, and for a surface structure of the aluminum plate: (a) an area (S) for a graphic formed by a reference straight line drawn from a top of a third highest mountain of a two-dimensional roughness curve downwardly by 1 &mgr;m and a roughness curve upper than the reference straight line is 30 &mgr;m2≦S≦150 &mgr;m2; (b) an average roughness Ra of average lines is 0.15 &mgr;m≦S≦Ra≦0.

Abstract: According to the present invention there is provided a heat ode imaging element for making a lithographic printing plate having n a lithographic base with a hydrophilic surface a first layer including a polymer, soluble in an aqueous alkaline solution and a top layer on the same side of the lithographic base as the first layer which top layer is IR-sensitive and unpenetrable or insoluble for an alkaline developer wherein said first layer and said top layer may be one and the same layer and said first layer and said top layer being the imaging layers; characterized in that said imaging layers have a glass transition temperature of at least 57° C.

Abstract: In accordance with the present invention there is provided an imaging element for lithographic offset printing. The imaging element comprises hydrophobic polymer particles in an aqueous medium, a substance for converting light into heat, and an organic base. The imaging element may be used for printing long run lengths on lower quality paper and in the presence of set-off powder. The imaging element may be imaged and developed on-press and may be sprayed onto a hydrophilic surface to create a printing surface that may be processed wholly on-press. The hydrophilic surface may be a printing plate substrate or the printing cylinder of a printing press or a seamless sleeve around the printing cylinder of a printing press. This cylinder may be conventional or seamless.

Abstract: The present invention discloses a planographic printing plate having a notched portion on its surface having a required size, and having smaller burrs at a rear face, and a planographic printing plate cutting device and a planographic printing plate cutting method for forming such a planographic printing plate by cutting. The planographic printing plate cutting device of the present invention includes an upper roller for forming a recessed section at the planographic printing plate. The upper roller, which is formed substantially into a disc shape as a whole, has a pressing portion parallel to a web (the planographic printing plate), and a slope portion that is slanted with respect to the surface of the web at a predetermined inclination. This upper roller presses the web such that a sloped face (recessed section) that is slanted with respect to the surface of the web is formed. Next, a shearing roller shears the web at the sloped face such that a remaining portion of the sloped face forms a notched portion.

Abstract: A method for preparing a lithographic printing plate by means of ink jet is disclosed. The ink jet fluid contains an oleophilizing compound chosen from the group consisting of a catechol, a pyrogallol, and a salicylic acid.

Abstract: A lithographic printing plate having an average curvature in a rolling direction of 1.5×10−3 mm−1 or less, a curvature distribution in a crosswise direction of 1.5×10−3 mm−1 or less, and a curvature in a direction perpendicular to said rolling direction of 1.0×10−3 mm−1 or less and a method for producing the printing plate are disclosed. A method for producing a support for a lithographic printing plate is also disclosed, which comprises roughening a surface of an aluminum web having a center line average surface roughness of 0.15 to 0.35 &mgr;m and a maximum surface roughness of 1 to 3.5 &mgr;m by at least one of mechanical surface roughening, chemical etching and electrochemical surface roughening, and then applying anodization thereto.

Abstract: Negative-working and positive-working lithographic plate constructions include a durable hydrophilic layer; a hard, inorganic, oleophilic layer; and a substrate, which may be metal. If a metal substrate is employed, an overlying layer provides sufficient thermal insulation to prevent substantial dissipation of heat—which is necessary to achieve ablation—into the substrate. In the case of oleophilic layers employed in negative-working embodiments, certain ceramic materials are suitable, and an intermediate tying layer may be used to anchor a hydrophilic ceramic layer to the oleophilic layer. In positive-working embodiments, the oleophilic layers may be refractory compounds doped with oleophilic material. An advantage to the latter embodiments is the ability to apply traditional means of correction following imaging.

Abstract: This invention discloses a lithographic plate comprising on a roughened substrate a substantially conformal radiation-sensitive layer. The radiation-sensitive layer can be a photo hardenable or photo solubilizable layer, or can be a laser ablatable layer. The radiation-sensitive layer is substantially conformally coated on the roughened substrate surface in a way so that the surface of the radiation-sensitive layer has peaks and valleys substantially corresponding to the major peaks and valleys of the substrate microscopic surface. The lithographic plate of such a configuration can provide no or low tackiness and excellent block resistance, while allowing excellent press durability. For on-press developable lithographic plate, such a plate configuration also allows excellent on-press developability.

Abstract: A lithographic printing plate having an average curvature in a rolling direction of 1.5×10−3 mm−1 or less, a curvature distribution in a crosswise direction of 1.5×10−3 mm−1 or less, and a curvature in a direction perpendicular to said rolling direction of 1.0×10−3 mm−1 or less and a method for producing the printing plate are disclosed. A method for producing a support for a lithographic printing plate is also disclosed, which comprises roughening a surface of an aluminum web having a center line average surface roughness of 0.15 to 0.35 &mgr;m and a maximum surface roughness of 1 to 3.5 &mgr;m by at least one of mechanical surface roughening, chemical etching and electrochemical surface roughening, and then applying anodization thereto.

Abstract: Provided is an imaged wet lithographic printing plate which bears a hydrophilic layer and an oleophilic, water-insoluble layer in a desired imagewise pattern overlying the hydrophilic layer, wherein the oleophilic layer comprises a reaction product of a transition metal complex of an organic acid, preferably a chromium complex of an organic carboxylic acid. Also provided are methods of preparing such imaged wet lithographic plates by ink jet printing and by laser ablation imaging; methods of preparing positive working, wet lithographic printing plates imageable by laser radiation; positive working, wet lithographic printing plates prepared by such methods; and methods of imaging such positive working plates by laser ablation imaging.

Abstract: A metal substrate is treated with a plurality of rotating brushes and a slurry of particulate material such that the treated surface is capable of absorbing incident infrared laser radiation. The substrate is itself capable of being visibly imaged by selective writing with an infrared laser. The substrate is coated with an ablatable coating which is transparent to the imaging infrared laser radiation. Selective exposure to infrared laser radiation ablates this coating in the laser exposed areas as a result of the absorption of infrared radiation by the substrate. The substrate can be anodized after rotary brush graining and still retain its ability to be imaged and ablate a coating. The coated article can be imaged in a computer-to-plate infrared laser imaging device. Depending on the specific coating and substrate selection, the imaged article can be used in a conventional lithographic printing process or in a dryographic printing process.

Abstract: The invention relates to thermal waterless lithographic printing plates comprising layers of inherent near infrared absorbing polymers for computer-to-plate and digital-offset-press technologies. More specially, this invention relates to thermal waterless lithographic printing plates, which can be imaged with near infrared laser light and which do not require post chemical processing step.More particularly, the present invention provides a thermal waterless printing plate suitable for near infrared laser imaging, said printing plate comprising:(i) a support substrate, and (ii) a composite top layer consisting of:(a) a near infrared absorbing adhesion promoting layer applied to the support substrate and(b) a near infrared absorbing ink repelling cross-linked silicone polymer layer.

Abstract: Methods and apparatus for lithographic imaging without ablation function by irreversibly debonding intermediate printing-plate layers, thereby rendering at least the surface layer removable by cleaning to expose, in an imagewise pattern, an underlying layer having a different affinity for ink and/or an abhesive fluid for ink. In contrast to ablation-type systems, it is unnecessary to destroy a plate layer, thereby reducing power requirements and facilitating increased imaging speeds.

Abstract: Lithographic printing members utilize, as an ink-accepting layer, a hard, inorganic, and generally covalent material that exhibits sufficient flexibility (at the deposition thicknesses envisioned) to accommodate flexing and bending. This layer may overlie a relatively heavy, metal plate substrate or support, resulting in a structure whose permanent layers all share the physical properties of inorganic materials. The printing member may also be provided with a protective layer that serves a variety of beneficial functions, including protection against handling and environmental damage and extension of plate shelf life, but which also is removed during the printing make-ready process.

Abstract: A thermally imagable element suitable for use as a lithographic printing plate is disclosed. Imagable element contains an ink repellent, thermally sensitive surface layer on a substrate. The surface layer contains an ink repellent, thermally sensitive co-polymer which is both thermally sensitive and has the physical properties needed for handling and printing. The thermally sensitive co-polymer contains two types of segments: (a) soft silicone segments, which repel ink, and (b) hard segments, which provide physical integrity and impart thermal sensitivity to the co-polymer. The element can be imaged by imagewise expose either by infrared radiation or by heat. The process requires no wet development step and no wiping. Thermally labile crosslinked polymers are also disclosed.

Abstract: The present invention provides a method for making a lithographic printing plate comprising the steps of:(1) image-wise exposing to light an imaging element comprising (i) on a hydrophilic surface of a lithographic base an image forming layer comprising hydrophobic thermoplastic polymer particles capable of coalescing under the influence of heat and dispersed in a hydrophilic binder and (ii) a compound capable of converting light to heat, said compound being comprised in said image forming layer or a layer adjacent thereto;(2) and developing a thus obtained image-wise exposed imaging element by mounting it on a print cylinder of a printing press and supplying an aqueous dampening liquid and/or ink to said image forming layer while rotating said print cylinder.

Abstract: This invention relates to a process for preparing printing plates which are used in offset printing. The process produces a plate which comprises a substrate film in which a thin durable hydrophilic layer has been applied thereto. In the process, the substrate film is first microroughened by pressure blasting so that the surface roughness, R.sub.A, is in the range 0.3 to 1.5 .mu.m. Subsequently, a durable, firmly adhering hydrophilic layer is applied to substrate by plasma-spraying an oxide powder with a particle size of 1 to 40 .mu.m onto the substrate. This process produces a plate whose surface is not greasy or grainy.

Abstract: Presensitized lithographic plates are prepared which permit direct formation of printable images on plates by digital computerization without the intervening formation of a photographic image with a quality that allows the plates to be used for high volume printing applications. The lithographic printing plate has a structure which contains a substrate; a positive or negative working photosensitive layer; and a thermally sensitive masking layer which is opaque to the actinic radiation but which is soluble in an aqueous medium. The masking layer contains a heat softenable disperse phase which is insoluble in the aqueous medium; a polymeric continuous phase which is soluble or swellable in the aqueous medium; and a colorant which strongly absorbs radiant energy and converts the radiant energy to heat.

Abstract: A laser imageable direct write printing member for use with a laser producing laser radiation comprising a flexible sheet of plastic having first and second surfaces serving as a film substrate. A vacuum-deposited laser ablative coating is carried by said first surface formed of a metal selected from a group consisting of titanium, zirconium, aluminum hafnium and alloys thereof.

Abstract: An aluminum planographic printing plate includes an aluminum support and a hydrophilic layer disposed at least on one surface thereof, wherein a corner defined with a surface having the hydrophilic layer and an end face of the aluminum planographic printing plate is constituted with a convexly curved surface with no bending portion, a portion of the convexly curved surface is covered with the hydrophilic layer, and a vertical distance between an end portion of the hydrophilic layer and the flat surface of the hydrophilic layer is 10 to 60 .mu.m.