Abstract: A coating solution and a method of manufacturing a magnesium-oxide layer on a glass substrate. The layer obtained is characterized by a satisfactory adhesion and a high secondary electron emission coefficient. The curing temperature can remain below 250.degree. C., so that the method is suitable for the customary types of glass.Said coating solution comprising a solvent and partially acetylated and partially hydrolyzed Mg(OR).sub.2 of the formula Mg(OH).sub.x (OR).sub.y (OAc).sub.z.

Abstract: An antireflective coating layer 22 is applied to a substrate 20, the coating layer having a refractive index gradient such that the refractive index decreases in the direction from the substrate surface 24 to the outside surface 26 of the coating layer. An organic solution of an alkoxide starting material is provided on the substrate and is converted into a gel in situ by means of a reaction with water, which gel is subsequently dried. During the formation of the gel the reaction conditions are varied in such a manner that a non-porous gel is formed in which the degree of crosslinking of the gel material increases in the direction from the substrate surface to the outside surface of the coating layer.

Abstract: The invention provides a method by means of which it becomes possible to produce emblems or wordmarks having three-dimensional symbols, both the front face and the raised side faces of which are metallized, while the substrate is not metallized. For that purpose, the symbols are injection molded with a carrier and they are not secured to a separately manufactured substrate until after the metallizing operation.

Abstract: A master suitable for the manufacture of electroplated negative metal copies. The master comprises a preform which on at least one side has a layer of electroplated aluminum. The surface has a precisely machined profile and is coated with a titanium nitride layer.

Abstract: An article which is covered with a nickel-phosphorus alloy is covered on its outer surface with a protective layer which comprises CrPO.sub.4, Cr(OH).sub.3 and may also comprise Cr.sub.2 (SO.sub.4).sub.3 and in which no nickel is present. The layer provides excellent corrosion protection. In a particular embodiment the layer is black, scratch-resistant in normal use, cannot be wiped off and is not sensitive to finger prints and is extremely suitable for decorative applications. The layers can be obtained electrolytically in a bath which comprises chromic acid and optionally phosphoric acid and sulfuric acid using reversed current in a given frequency range, a given range of current densities and a given range of ratios of cathodic to anodic pulse durations. In order to obtain the black layers the cathodic time duration is only a fraction of the anodic time duration.

Abstract: An optically readable information disc having a reflective optical structure which comprises a reflective layer which is composed of a nitride, carbide or boride of a transition metal selected from the group consisting of titanium, zirconium, hafnium, vanadium, chromium, niobium, molybdenum, lanthanum, tantalum and tungsten.

Abstract: A metal article which covered with a nickel-phosphorus alloy and which is covered on its outer surface with a protective layer which comprises CrPO.sub.4, Cr(OH).sub.3 and may also comprise Cr.sub.2 (SO.sub.4).sub.3 and in which no nickel is present. The layer provides an excellent corrosion protection. In a particular embodiment the layer is black, scratch-resistant in normal use, cannot be wiped off and is not sensitive to finger prints and is extremely suitable for decorative applications. The layers can be obtained electrolytically in a bath which comprises chromic acid and optionally reversed current in a given frequency range, a given range of current densities and a given range of ratios of cathodic to anodic pulse durations. In order to obtain the black layers the cathodic time duration is only a fraction of black layers the anodic time duration.

Abstract: Treating objects of which at least the surface consists of tin in order to obtain a satisfactory corrosion resistance. To this end the objects are subjected in a tungstate solution of at least 0.02 M and having a pH of 4-11 alternately to a cathodic and an anodic polarity (so-called periodically reversed current). The frequency with which the current reverses must be between 0.2 and 2 Hz and the current density must be between 0.2 and 1 A/dm.sup.2, the ratio of the anodic to the cathodic density being from 0.5-1.

Abstract: Ion-selective electrode for determining the concentration of one specific ion in a solution of a mixture of different ions. The active material consists of Ag.sub.3 SBr or Ag.sub.3 SI. The electrode is used for the selective determination of Br.sup.-, I.sup.- or Ag.sup.+.