Abstract: A lithographic printing plate precursor which comprises a support having provided thereon a layer containing a light-to-heat converting agent as a lower layer and a hydrophilic photosensitive layer containing light-to-heat convertible metallic fine particles which change to hydrophobic with the conversion of light to heat as an upper layer.

Abstract: A lithographic printing plate precursor which comprises a support having provided thereon a layer comprising a hydrophilic medium, wherein the layer comprising a hydrophilic medium contains a hydrophobitization precursor having a hydrophilic surface and a light/heat converting agent which is hydrophilic in itself, or at least on the surface.

Abstract: A heat mode type lithographic printing plate precursor which can be directly mounted on a printing press without development processing after scanning exposure for a short time to conduct plate-making, has excellent press life and also gives few print stains onto a printed face, which comprises a substrate having provided thereon an image recording layer containing fine light-heat convertible particles which are coated with a hydrophilic material, the layer being made hydrophobic by the action of heat.

Abstract: An offset printing plate precursor comprising a substrate having provided thereon a layer containing a substance capable of absorbing radiant rays and converting the radiant energy to heat energy, and a thin layer, wherein printing is performed by following the steps of: (a) subjecting the printing plate precursor to irradiation with active light, (b) subjecting the printing plate precursor to irradiation with light/heat convertible radiant rays or heat treatment, to thereby imagewise distribute a hydrophilic area and a lipophilic area of the thin layer, and (c) bringing the thin layer into contact with printing ink to form a printing plate in which the lipophilic area has received the printing ink, to thereby perform offset printing.

Abstract: An object of the present invention is to provide excellent in terms of durability wherein development with water, or direct production of the plate from digital data through infrared laser recording in particular such that a special process is not necessary, is possible, by forming on a support a photosensitive layer containing a reaction product of a compound having in a molecule thereof a functional group X and a functional group Y and a compound represented by a formula (1) stated below, or alternatively, containing a polymerization product of a compound having the functional group X and a compound represented by the formula (1) stated below. Further by incorporating water-insoluble particles in this photosensitive layer, many voids are formed in the photosensitive layer, further improving sensitivity and discrimination.

Abstract: A lithographic printing plate precursor which comprises a support having provided thereon a layer containing a light-to-heat converting agent as a lower layer and a hydrophilic photosensitive layer containing light-to-heat convertible metallic fine particles which change to hydrophobic with the conversion of light to heat as an upper layer.

Abstract: A radiant ray-sensitive lithographic printing plate precursor which comprises (a) material or material series which absorbs radiant rays, converts the absorbed radiant rays to heat, and enters into a self-exothermic reaction by the heat, and (b) material or material series which causes a chemical change or a physical change by the reaction heat generated as a result of the self-exothermic reaction.

Abstract: A precursor for a lithographic printing plate having an aluminum support subjected to at least two graining treatments and simultaneously satisfying the ranges shown by following (1), (2), and (3);1.5.ltoreq.R.sub.ms (10 to 100 .mu.m)/R.sub.ms (1 to 10 .mu.m).ltoreq.3.0(1 )0.2.ltoreq.R.sub.ms (1 to 10 .mu.m).ltoreq.0.4 [.mu.m] (2)0.4.ltoreq.R.sub.ms (10 to 100 .mu.m).ltoreq.1.0 [.mu.m] (3)wherein the R.sub.ms is the square average surface roughness obtained by measuring the surface form of the support by the AFM, the R.sub.ms (1 to 10 .mu.m) is the value about the frequency space of from 1 to 10 .mu.m, and the R.sub.ms (10 to 100 .mu.m) is the value about the frequency space of from 10 to 100 .mu.m. The lithographic printing plate using the aluminum support has greatly improved various characteristics such as scumming, the printability, the printing impression, etc.

Abstract: A radiation-sensitive planographic printing plate which is excellent in terms of durability wherein development with water, or direct production of the plate from digital data through infrared laser recording in particular such that a special process is not necessary, is possible, by forming on a support a photosensitive layer containing a reaction product of a compound having in a molecule thereof a functional group X and a functional group Y and a compound represented by a formula (1) stated below, or alternatively, containing a polymerization product of a compound having the functional group X and a compound represented by the formula (1) stated below. Further by incorporating water-insoluble particles in this photosensitive layer, many voids are formed in the photosensitive layer, further improving sensitivity and discrimination.

Abstract: A support for a lithographic printing plate having a corrugated surface processed by roughening, wherein the corrugation on the support surface comprises big corrugation having an average pitch of from not less than 5 .mu.m to not more than 30 .mu.m, and middle corrugation superimposed on the big corrugation, the middle corrugation comprising honeycomb pits having an average diameter of from not less than 0.5 to not more than 3.0 .mu.m, and the support surface has a surface inclination distribution which comprises an inclination of not less than 30 degrees in a proportion of from not less than 5% to not more than 20% as determined by an atomic force microscope. A process for the preparation of the support and an electrolytic treatment apparatus for the process are also described.

Abstract: An aluminum support for a lithographic printing plate used in off-set printing or the like is disclosed, having a surface shape determined using an atomic force microscope (AFM) such that when measured within the measurement range of 100 .mu.m square with the resolution in the horizontal (X, Y) direction being 0.1 .mu.m, assuming that the surface area obtained by an approximate three-point problem is .alpha. and the upper projected area is .beta., the .alpha./.beta. value (specific surface area) is from 1.15 to 1.5, and when measured within the measurement range of 240 .mu.m square with the resolution in the horizontal (X, Y) direction being 1.9 .mu.m, the average surface roughness is from 0.35 to 1.0 .mu.m and the ratio of the sum of the surface area where the gradient of 30.degree. or more to the total surface area is from 5 to 40%.

Abstract: A magnetic recording medium is described, comprising a nonmagnetic support having thereon a magnetic layer containing a binder which is cross-linkable or polymerizable by radiation irradiation and ferromagnetic particles, the ferromagnetic particles being metal or metal alloy particles mainly comprising iron having a crystal size of 300 .ANG. or less, having an atomic ratio of oxygen atoms to iron atoms of from 1.6 to 3.0 on the surface of the particles, and the magnetic layer having been irradiated with radiation, and comprising a nonmagnetic support having thereon a magnetic layer containing a binder comprising thermoplastic resins, thermosetting resins, reactive type resins and mixtures thereof and ferromagnetic particles, said ferromagnetic particles being metal or metal alloy particles mainly comprising iron having a crystal size of 250 .ANG. or less, and having an atomic ratio of oxygen atoms to iron atoms of from 1.6 to 3.0 on the surface of said particles.

Abstract: A magnetic recording medium comprises a non-magnetic substrate, a thin ferromagnetic film layer overlaid on the substrate, and a polymer film formed by plasma polymerization. The thin ferromagnetic film layer is composed of ferromagnetic columnar grains. The polymer film is overlaid on the thin ferromagnetic film layer so as to permeate into the spaces between the ferromagnetic columnar grains, thereby improving the corrosion resistance and durability of the magnetic recording medium.

Abstract: A metal thin film type magnetic recording medium having an improved weather resistance is disclosed, which comprises a non-magnetic support base having provided thereon a ferromagnetic metal thin film comprised of column-shaped clusters of ferromagnetic particle having longitudinal axes inclined to the surface plane of the support base and a layer of a chromium compound such as Cr and Cr.sub.2 O.sub.3 covering the surfaces of the column-shaped clusters.

Abstract: A magnetic recording medium comprises a non-magnetic substrate, a thin magnetic metal film layer overlaid on the substrate, a metallic oxide layer formed on the surface of the thin magnetic metal film layer, and a polymer film formed by plasma polymerization. The polymer film is overlaid on the metallic oxide layer to improve the corrosion resistance and durability of the magnetic recording medium.