Abstract: A high-quality oxide film which is free from a pinhole and surface roughing caused by anodic oxidation and which has surface smoothness on a surface of a material to be treated containing a metal as a principal component. An electrolyte solution which is used for forming an oxide film on a surface of a material to be treated containing a metal as a principal component by anodic oxidation, the electrolyte solution containing a non-aqueous solvent containing an alcoholic hydroxyl group and having 4 or more carbon atoms as a main solvent. This non-aqueous solvent preferably contains two or more alcoholic hydroxyl groups and is especially preferably one or two or more members selected from the group consisting of diethylene glycol, triethylene glycol and polyethylene glycol. A method of forming an oxide film including a step of anodically oxidizing a material to be treated containing a metal as a principal component in this electrolyte solution.

Abstract: In a stable gold plating liquid having a low toxicity besides properties comparable to those of a cyan-type gold plating liquid, iodine and/or iodide ions, gold ions, and a polyalcohol having at least 4 carbon atoms are contained. The polyalcohol having at least 4 carbon atoms may be diethylene glycol or triethylene glycol. The content of the polyalcohol having at least 4 carbon atoms in the gold plating liquid is generally 10 to 90 percent by weight. The gold plating liquid may contain water.

Abstract: A high-quality oxide film which is free from a pinhole and surface roughing caused by anodic oxidation and which has surface smoothness on a surface of a material to be treated containing a metal as a principal component. An electrolyte solution which is used for forming an oxide film on a surface of a material to be treated containing a metal as a principal component by anodic oxidation, the electrolyte solution containing a non-aqueous solvent containing an alcoholic hydroxyl group and having 4 or more carbon atoms as a main solvent. This non-aqueous solvent preferably contains two or more alcoholic hydroxyl groups and is especially preferably one or two or more members selected from the group consisting of diethylene glycol, triethylene glycol and polyethylene glycol.

Abstract: A silver or silver alloy thin layer on a substrate is etched by an etching liquid uniformly without producing an etching residue while avoiding side etching due to over etching. The etching liquid contains silver ions in a range from 0.005 to 1 weight %. The etching liquid is fed to a tank or an etching liquid feeding apparatus, and then brought into contact with the silver or silver alloy thin layer on the substrate.

Abstract: A silver or silver alloy thin layer on a substrate is etched by an etching liquid uniformly without producing an etching residue while avoiding side etching due to over etching. The etching liquid contains silver ions in a range from 0.005 to 1 weight %. The etching liquid is fed to a tank or an etching liquid feeding apparatus, and then brought into contact with the silver or silver alloy thin layer on the substrate.

Abstract: Disclosed herein is a paper-making additive.comprising a specified cationic polymer having an amidine structure. The cationic polymer additive for paper-making according to the present invention has 20 to 90% by mole of units represented by the formula (1) and/or (2): ##STR1## wherein R.sup.1 and R.sup.2 independently denote a hydrogen atom or a methyl group, and X- denotes an anion; and has a reduced viscosity of 0.1 to 10 dl/g as measured in a 1N saline solution of 0.1 g/dl at 25.degree. C. The additives are excellent in improving paper or pulp properties, such as freeness, filler retention and paper strength.

Abstract: Disclosed herein is a flocculating agent comprising a specified cationic polymer having an amidine structure. The cationic polymer flocculating agents according to the present invention have 20 to 90% by mole of a repeating amidine unit represented by the formula (1) and/or (2): ##STR1## The agents have a reduced viscosity of 0.1 to 10 dl/g as measured in a 1N saline solution of 0.1 g/dl at 25.degree. C.The agents have a remarkably excellent performance as flocculating agents, in particular for organic sludge.