Abstract: This zinc-nickel composite plating bath contains a zinc source, a nickel source, silicon dioxide particles and an ammonium-based dispersant in such ranges that enable the achievement of a zinc-nickel composite plating film wherein the codeposition amount of nickel is 10-16 wt % and the codeposition amount of the silicon dioxide particles is 7 vol % or more. Meanwhile, the pH of this zinc-nickel composite plating bath is 5.6 to 6.8.

Abstract: This zinc-nickel composite plating bath contains a zinc source, a nickel source, silicon dioxide particles and an ammonium-based dispersant in such ranges that enable the achievement of a zinc-nickel composite plating film wherein the codeposition amount of nickel is 10-16 wt % and the codeposition amount of the silicon dioxide particles is 7 vol % or more. Meanwhile, the pH of this zinc-nickel composite plating bath is 5.6 to 6.8.

Abstract: A cylinder barrel inside surface treatment apparatus for providing a uniform treatment finish is disclosed. The treatment apparatus includes a pallet on which a cylinder block is placed with a gasket surface faced upward. A top opening of a cylinder barrel of the cylinder block is covered by a cover member having a concave portion communicating with the top opening. A nozzle having treatment solution spray holes is attached to the cover member. The treatment solution is sprayed toward a wall of the concave portion from the treatment solution spray holes and flows along the wall from a top end to a bottom end of the cylinder barrel inside surface.

Abstract: A plating apparatus has a tubular electrode (16) placed in a hollow section (12) of work (11). The tubular electrode (16) has a through-hole (16a) formed in the longitudinal direction. A circular tube-like gap (S1) in which a plating liquid (17) flows is formed between the tubular electrode placed in the hollow section and an inner peripheral wall (14) of the hollow section. The plating liquid flows spirally from the lower end of the gap to the upper end by action of a vortex producing flow path (29) communicating to the lower end of the gap. The plating liquid having reached the upper end circulates through the through-hole of the tubular electrode.

Abstract: By a press-formed starting member (11) being immersed in a process liquid (12) at 40 to 60° C. and of pH 9 to 12, a passive film (26) is formed at the surface of the press-formed starting member. There is no solving out of metal ions from the press-formed starting member, and the passivation treatment can be carried out by just immersion in a single solution, so that costs including waste processing can be reduced. In another aspect, degreasing, cleaning and passivation treatment are carried out by spraying the press-formed starting member. By the use of spraying, the degreasing, cleaning and passivation treatment can be made rapid, and the amounts of process liquid needed for degreasing, cleaning and passivation treatment can be reduced.

Abstract: A plating apparatus has a tubular electrode (16) placed in a hollow section (12) of work (11). The tubular electrode (16) has a through-hole (16a) formed in the longitudinal direction. A circular tube-like gap (S1) in which a plating liquid (17) flows is formed between the tubular electrode placed in the hollow section and an inner peripheral wall (14) of the hollow section. The plating liquid flows spirally from the lower end of the gap to the upper end by action of a vortex producing flow path (29) communicating to the lower end of the gap. The plating liquid having reached the upper end circulates through the through-hole of the tubular electrode.

Abstract: A composite nickel and copper alloy plating film (3) containing nickel and copper. Nickel is of high wear resistance and a nickel alloy improves the wear resistance of the film. Copper is of high corrosion resistance and a copper alloy improves the corrosion resistance of the film. The film may further contain self-lubricating particles and hard particles which ensure its wear resistance and lubricating property to a further extent.

Abstract: A composite nickel and copper alloy plating film (3) containing nickel and copper. Nickel is of high wear resistance and a nickel alloy improves the wear resistance of the film. Copper is of high resistance of the film. The film may further contain self-lubricating particles and hard particles which ensure its wear resistance and lubricating property to a further extent.

Abstract: By a press-formed starting member (11) being immersed in a process liquid (12) at 40 to 60° C. and of pH 9 to 12, a passive film (26) is formed at the surface of the press-formed starting member. There is no solving out of metal ions from the press-formed starting member, and the passivation treatment can be carried out by just immersion in a single solution, so that costs including waste processing can be reduced. In another aspect, degreasing, cleaning and passivation treatment are carried out by spraying the press-formed starting member. By the use of spraying, the degreasing, cleaning and passivation treatment can be made rapid, and the amounts of process liquid needed for degreasing, cleaning and passivation treatment can be reduced.

Abstract: A composite nickel and copper alloy plating film (3) containing nickel and copper. Nickel is of high wear resistance and a nickel alloy improves the wear resistance of the film. Copper is of high resistance of the film. The film may further contain self-lubricating particles and hard particles which ensure its wear resistance and lubricating property to a further extent.

Abstract: A composite plating apparatus includes a cylindrical electrode which is positioned in a hollow section of a workpiece with a surrounding gap left therebetween. A plurality of through-holes are formed across the thickness of an outer wall of the cylindrical electrode. Composite plating liquid is jetted out through the through-holes and impinge on the inner surface of the hollow section to thereby produce turbulence. The turbulent liquid provides a uniform distribution of ceramic particles in the liquid. As a result, the ceramic particles can be co-deposited uniformly in a metallic matrix, and hence a uniform abrasion-resistant characteristic is obtained all over a resultant composite plating film.

Abstract: The present invention relates to a chromone derivative and an aldose reductase inhibitor comprising said compound as efective component, which is represented by the following formula: ##STR1## wherein R.sub.1 and R.sub.2 each represent a lower alkyl group, etc., R.sub.3 represents an oxygen atom, a sulfur atom, etc., R.sub.7 represents a phenyl group substituted or not substituted, etc., and R represents a hydrogen atom or a lower alkoxy group. The present compounds exhibit superior inhititory action on aldose reductase and are useful for the treatment of various complications of diseases in diabetes, such as cataract, retinopathy, keratopathy, nephropathy, and neuropathy.

Abstract: The present invention relates to a chromone derivative and an aldose reductase inhibitor comprising said compound as efective component, which is represented by the following formula: ##STR1## wherein R.sub.1 and R.sub.2 each represent a lower alkyl group, etc., R.sub.3 represents an oxygen atom, a sulfur atom, etc., R.sub.7 represents a phenyl group substituted or not substituted, etc., and R represents a hydrogen atom or a lower alkoxy group. The present compounds exhibit superior inhititory action on aldose reductase and are useful for the treatment of various complications of diseases in diabetes, such as cataract, retinopathy, keratopathy, nephropathy, and neuropathy.

Abstract: The present invention relates to a chromone derivative and an aldose reductase inhibitor comprising said compound as efective component, which is represented by the following formula: ##STR1## wherein R.sub.1 and R.sub.2 each represent a lower alkyl group, etc., R.sub.3 represents an oxygen atom, a sulfur atom, etc., R.sub.7 represents a phenyl group substituted or not substituted, etc., and R represents a hydrogen atom or a lower alkoxy group. The present compounds exhibit superior inhititory action on aldose reductase and are useful for the treatment of various complications of diseases in diabetes, such as cataract, retinopathy, keratopathy, nephropathy, and neuropathy.