Abstract: A diazonium salt polycondensation product which comprises units of(a) a diazonium salt represented by the formula ##STR1## in which R.sup.1, R.sup.2 and R.sup.3 are hydrogen atoms, halogen atoms, alkyl groups or alkoxy groups andX is the anion of an aminoalkanesulfonic acid, and(b) a compound represented by the formulaR.sup.4 --O--CH.sub.2 --R.sup.6 --CH.sub.2 --O--R.sup.5 (II)in whichR.sup.4 and R.sup.5 are hydrogen atoms, alkyl groups or aliphatic acyl radicals andR.sup.6 is the radical of an aromatic hydrocarbon, a phenol, a phenol ether, an aromatic thioether, an aromatic heterocyclic compound or an organic acid amide,and which is suitable as a light-sensitive substance for the preparation of planographic printing plates that can be developed with pure water.

Abstract: An electrophotographic recording material comprising an electrically conductive base material and at least one photoconductive layer containing an organic photoconductor, a binder, and at least one sensitizing dye represented by the formula ##STR1## wherein n denotes 2 or 3 and X.sup.- denotes a monovalent anion. The sensitizing dye has a sensitization maximum between 650 and 840 nm.

Abstract: An electrophotographic recording material is disclosed which comprises an electrically conductive support and a photoconductive layer containing a photoconductor comprised of zinc oxide, a binder, and a sensitizing agent comprised of an alkylated trimethine-cyanine dye having a particular structure. The disclosed electrophotographic material possesses a sharply pronounced, selective sensitization having a peak at about 495 nm, and can be safely handled under green, yellow and red safelights.

Abstract: In an electrophotographic recording material comprising an electrically conductive base material and at least one photoconductive layer containing a photoconductor, a binder and at least three sensitizing dyes of which at least two are 3,3'-dimethylindolenine compounds, such as bis-(3,3'-dimethylindolenyl)-trimethinecyanines and -pentamethinecyanines, having a sensitizing action in different wavelength regions, it is possible to sensitize various organic and inorganic photoconductors within the range from about 400 to 700 nm.

Abstract: An electrophotographic recording material is described which comprises an electrically conductive support and a photoconductive layer comprising a photoconductor, a binder, and at least one bis-benzothiazole-pentamethine-cyanine having a particular structure. The aforementioned recording material displays a sensitization peak in the range between about 680 nm and 710 nm, and can be processed under visual control using bright safelights.

Abstract: An electrophotographic recording material comprising an electrically conductive support, a photoconductor layer and an about 1 to about 50 .mu.m thick protective layer comprising a radiation-hardened, crosslinked polyester which is formed from trimethylol propane, adipic acid and acrylic acid and which has a surface resistance ranging from about 5.5.multidot.10.sup.12 to about 2.5.multidot.10.sup.13 ohm and a volume resistivity ranging from about 7.multidot.10.sup.10 to about 5.multidot.10.sup.13 ohm cm, measured at 23.degree. C. and 50 percent relative humidity, and a process for producing such a recording material.