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: The invention describes a photopolymerizable recording material which comprises a photopolymerizable layer and a cover layer. The cover layer comprises a polymer which possesses low permeability to atmospheric oxygen and is soluble in water, and a water-soluble dye which absorbs light in the region from 300 to 700 nm and within this range has a non-absorbent region corresponding to the emission range of the copying light source.The material can be sensitized for various spectral regions, for example, for UV light, visible light or laser light and has a higher resolving power than a corresponding material which does not contain a dye in the cover layer, while its photosensitivity remains unchanged or is only slightly reduced.

Abstract: A process for developing irradiated radiation-sensitive recording materials using an aqueous-alkaline developer which contains compounds of the formula (I) ##STR1## wherein A is H, Na, K, NH.sub.4 or NR.sub.4, whereR is a substituted or unsubstituted alkyl radical,W and X, independently of one another are H or --CH.sub.2 --COOA,Y is H or COOA andZ is H or OH,wherein the compound of the formula (I) contains at least 3 COOA units.

Abstract: A photosensitive recording material is described which has a layer base, a negative-working photosensitive layer containing a diazonium salt and a water-insoluble polymeric binder which is soluble or swellable in aqueous alkaline solutions, and a discontinuous top layer which forms a rough surface and which is composed of particles of a water-insoluble polymer which is dispersible in water in the presence of anionic or anionic/nonionic dispersants and which has a content of free acid groups or acid groups neutralized by salt formation of less than 0.8 mmol/g, the mean height of the particles being 2 to 6 .mu.m, the maximum height less than 10 .mu.m, the mean horizontal diameter less than 40 .mu.m, the maximum diameter less than 80 .mu.m and the number of particles being 100 to 10,000 per cm.sup.2. The material is suitable for the production of planographic printing plates and requires only short vacuum times in a vacuum-operated copying frame.

Abstract: An electrophotographic recording material comprising:an electrically conductive base layer;a photoconductive layer which can be de-coated with alkaline solutions, the photoconductive layer comprising an organic photoconductor, a sensitizer and a binder comprising a mixture of:a) a copolymer comprising units composed of a first vinyl aromatic compound and units composed of maleic anhydride and/or a maleic partial ester, andb) a copolymer comprising units composed of a second vinyl aromatic compound and units of (meth)acrylic acid.

Abstract: A process for the production of a lithographic printing plate is described, in which a photosensitive material comprising a substrate suitable for lithographic printing, a hydrophilic intermediate layer, a photopolymerizable layer which changes its adhesion to the hydrophilic layer and/or to the cover sheet on exposure to light and a transparent cover sheet provided with an exposure mask which is non-transparent to actinic light is exposed to actinic light through the exposure mask, and the photopolymerizable layer is developed to give the image by peeling off the cover sheet from the substrate.The process is carried out in all stages without the use of chemicals and gives printing plates having good oleophilic properties and a long press life.

Abstract: A process for developing irradiated radiation-sensitive recording materials using an aqueous-alkaline developer which contains compounds of the formula (I) ##STR1## wherein A is H, Na, K, NH.sub.4 or NR.sub.4, whereR is a substituted or unsubstituted alkyl radical,W and X, independently of one another are H or --CH.sub.2 --COOA,Y is H or COOA andZ is H or OH,wherein the compound of the formula (I) contains at least 3 COOA units.

Abstract: The invention relates to a non-continuous matte layer that can be used with a recording material having a substrate and a radiation-sensitive layer which contains a 1,2-naphthoquinone-2-diazide and an organic, polymeric binder which is insoluble in water but soluble in aqueous alkaline solutions. This matte layer comprises 100 to 10,000 particles per square centimeter which have a mean diameter of less than 40 .mu.m and a maximum diameter of less than 80 .mu.m and a mean height of 2 to 6 .mu.m and a maximum height of 10 .mu.m, and contains a resin which has up to 0.80 mmol of acid groups and/or salt groups per gram. The matte layer is obtained by spraying on and drying an aqueous, anionically or anionically/nonionically stabilized dispersion of the resin.

Abstract: The invention describes a solvent mixture for photohardenable compositions, which includes(a) a first component having(i) a first constituent of(aa) a polar solvent of the formula R-OH, wherein R is a H or alkyl, or(aa') a monoalkylether or an alkylether ester of a glycol and constituent of(ii) a second an organic solvent having a boiling point in the range of from about 60.degree. to 160.degree. C. and comprising an aliphatic ketone, an alkanoic acid alkylester, a hydroxyalkanoic acid alkylester or a cyclic ether,in quantitative proportions selected to form a homogeneous mixture, andb) from about 0.1 to 8% by weight, relative to the total solvent mixture, of another solvent, the boiling point of which is higher than each individual boiling point of the constituents of the first component (a). The solvent mixture is used to obtain coating solutions layers which have a higher photosensitivity than corresponding layers prepared without the addition of component (b).

Abstract: The invention describes a developing solvent for layers which are crosslinkable by photopolymerization and contain a binder based on an elastomeric polymer, a photopolymerizable monomer compatible therewith and a photoinitiator. The developing solvent comprises a phenol ether of the general formula I ##STR1## wherein R.sup.1 denotes (C.sub.1 -C.sub.6)n-alkyl or iso-alkyl, cycloalkyl or (C.sub.6 -C.sub.12)-aryl andR.sup.2 denotes hydrogen, (C.sub.1 -C.sub.6)n-alkyl or iso-alkyl or --OR.sup.1, and a relatively high-boiling alcohol.Compared with solvents of the prior art, the developing solvent of the present invention is non-toxic, can quickly be removed from the layer and has a high capacity for layer components.

Abstract: A photopolymerizable mixture is described, which contains a polymeric binder; an acrylate or alkacrylate of a polyhydric alcohol possessing at least one photooxidizable group; a compound or a combination of compounds being capable of initiating the polymerization of the ester under the action of light in the spectral region of 450 nm to 650 nm; and at least one compound which absorbs light in the region below 450 nm or which upon exposure forms a compound absorbing light in said region, whereby the optical density of the exposed mixture in this region is at least 2.0 at a layer thickness of 2 .mu.m. The mixture is useful for the production of masters or intermediate masters for reprographic layers being sensitive to light in the UV region, exposure of the mixture itself being performed with visible light.

Abstract: A photopolymerizable mixture is disclosed which comprisesa) a polymeric binder,b) an acrylate or alkacrylate of a polyhydric alcohol containing one or more groups which are photooxidizable on exposure in the presence of the photoreducible dye, and one or more urethane groups,c) a photoreducible dye as photoinitiator.The mixture is suitable for the production of printing plates and photoresists and is distinguished by increased photosensitivity, which can be even further increased by the addition of a photolytically cleavable compound which contains at least one trihalomethyl group. A recording material comprising the photopolymerizable mixture is also disclosed.

Abstract: The invention describes a developing solvent for layers which are crosslinkable by photopolymerization and contain a binder based on an elastomeric polymer, a photopolymerizable monomer compatible therewith and a photoinitiator. The developing solvent comprises a phenol ether of the general formula I ##STR1## wherein R.sup.1 denotes (C.sub.1 -C.sub.6)n-alkyl or iso-alkyl, cycloalkyl or (C.sub.6 -C.sub.12)-aryl andR.sup.2 denotes hydrogen, (C.sub.1 -C.sub.6)n-alkyl or iso-alkyl or --OR.sup.1.Compared with solvents of the prior art, the developing solvent of the present invention is non-toxic, can quickly be removed from the layer and has a high capacity for layer components.

Abstract: The invention relates to a positive-working radiation-sensitive mixture and a copying material produced therefrom on a layer support. The mixture contains as essential constituents a 1,2-quinone diazide or a combination of:1) a compound forming strong acid when exposed to actinic radiation and2) a compound containing at least one acid-cleavable C--O--C bond,and a binder with repeating units of the general formula I ##STR1## wherein R.sub.1 denotes a hydrogen or halogen atom, or a cyanide or an alkyl group,R.sub.2, R.sub.3, R.sub.4 are identical or different and denote hydrogen, or alkyl or aryl groups,R.sub.5, R.sub.6 and optionally R.sub.7 are identical or different and denote hydrogen or halogen atoms, or alkyl, aryl or alkoxy groups, andX denotes the atoms necessary to complete a mononuclear or polynuclear carbocyclic aromatic ring system, andn is 1, 2 or 3.

Abstract: A photopolymerizable mixture is described comprising (a) a polymeric binder, (b) an acrylate or alkacrylate of a polyhydric alcohol, said compound being free of urethane groups and further comprising at least one group which is photooxidizable on exposure to actinic radiation in the presence of a photoreducible dye, (c) a photoinitiator comprising a photoreducible dye, (d) a second photoinitiator comprising a trihalomethyl compound capable of being cleaved by irradiation, and (e) a third photoinitiator comprising an acridine, phenazine or quinoxaline compound. The mixture is suitable for the production of printing plates and photoresists and displays increased photosensitivity.

Abstract: A photopolymerizable mixture is described comprising (a) a polymeric binder, (b) an acrylate or alkacrylate of a polyhydric alcohol, said compound comprising at least one group which is photooxidizable on exposure to actinic radiation in the presence of a photoreduciable dye, (c) a photoinitiator comprising a photoreducible benzoxanthene or benzothioxanthene dye, and (d) a second photoinitiator comprising a trihalomethyl compound capable of being cleaved by irradiation. The mixture is suitable for the production of printing plates and photoresists and displays increased photosensitivity.

Abstract: A photopolymerizable composition is described comprising (a) a polymeric binder, (b) an acrylate or alkacrylate of a polyhydric alcohol, said acrylate or alkacrylate being free of urethane groups and further comprising at least one group which is photooxidizable on exposure to actinic radiation in the presence of a photoreducible dye, (c) a photoinitiator comprising a photoreducible dye, and (d) a second photoinitiator comprising a trihalomethyl compound capable of being cleaved by irradiation. The composition is suitable for production of printing plates and photoresists and displays increased photosensitivity.

Abstract: A photopolymerizable mixture is disclosed comprising:(a) a polymeric binder,(b) an acrylate or alkacrylate of a polyhydric alcohol containing one or more groups which are photooxidizable on exposure in the presence of the photoreducible dye, and one or more urethane groups,(c) a photoreducible dye as photoinitiator,(d) a trihalomethyl compound which can be cleaved by irradiation, and(e) an acridine or phenazine compound which is active as a photoinitiator.The mixture is suitable for the production of printing plates and photoresists and is distinguished by increased photosensitivity.

Abstract: A positive-working photosensitive mixture containing an o-quinone diazide and a binder is disclosed wherein the mixture contains a compound which is able to form an azo coupling with the o-quinone diazide. A copying material produced with the photosensitive mixture has a high photosensitivity and an exceptional developer resistance. The photosensitive mixture is used in reproduction technique, and also in the field of resists.

Abstract: A process is disclosed for the selective additive correction of voids in copying layers, in which electrically conductive aqueous solutions of an organic compound are deposited in the void, with direct current connection between conductive substrate and at least one electrode, and with a current density in the range from 0.01 to 100 A/dm.sup.2. The process is preferably carried out using organic polymers with substrates composed of metal, for example, aluminum, in grained and anodized form.