Nisshin Steel Co., Ltd.

Sumitomo Heavy Industries, Ltd.

Kiyoshi Takatsu

Eiki Takeshima

Takahiro Fujii

Youichi Kojima

Hirokazu Yano

Takeshi Takeuchi

Minoru Kiyotsuka

Masahiro Hozumi

Hidehiro Shibata

Hisao Takamura

Yoshikatsu Udagawa

Norio Asano

A paint composition containing a corrosion inhibitor A prepared from porous silica particles, to which Ca ion is bonded by ion-exchange, and a polyphosphate B preferably at an A/B weight ratio of 60/40 to 5/95 and at an A+B ratio of 5-150 parts by weight based on 100 parts by weight of resinous components. A base metal sheet is preferably one pre-treated with a chemical agent containing at least one fluoroacid. Since the polyphosphate B controls dissolution of Ca ion, an effect of Ca ion on corrosion inhibition is maintained over a long term. The painted metal sheet does not put harmful influences on the environment, since it does not contain chromium compounds.

CR-free paint compositions and painted metal sheets

This invention relates to a shielding material used as a radiation shield of a container containing radioactive wastes. A radiation shield with an excellent heat-transferring property is fabricated from composite particles (A) obtained by coating core particles (a) of radiation-shielding property with a metal (b) of high thermal conductivity. Composite particles are formed into a certain shape of radiation shield by hot-press forming or other forming or packed into the internal space of radioactive waste container or the shield container cavity to compose a radiation shield.

Radiation shield and shielding material with excellent heat-transferring

Disclosed herein suspension electroplating of fine particles with metal. An electroplating operatively equipped with a cathode and anode is charged with a a metallic ion-containing electrolyte and particles to be electroplated. The particles have a size of from 0.1 to 10 .mu.m. At least a part of the surface of each particle is conductive. Such a stationary circulating flow of a suspension of the particles in the electrolyte is formed in the bath that the particles are maintained in the suspended condition; the suspension is circulated substantially without coming in contact with the anode; the particles may have a chance of colliding with substantially all surface areas of the working surface of the cathode, and are repeatedly brought in collision with the cathode at a velocity with a normal component of from 0.6 to 6.0 m/min; and a particle concentration of the suspension at the time of collision is from 30 to 55% by volume. When such a stationary flow has been formed, a current for electroplating is caused to pass, whereupon deposition of metal on the particles proceeds without deposition of the particles and metal on the cathode.

Electroplating of fine particles with metal

Disclosed herein suspension electroplating of fine particles with metal. An electroplating operatively equipped with a cathode and anode is charged with a metallic ion-containing electrolyte and particles to be electroplated. The particles have a size of from 0.1 to 10 .mu.m. At least a part of the surface of each particle is conductive. Such a stationary circulating flow of a suspension of the particles in the electrolyte is formed in the bath that the particles are maintained in the suspended condition; the suspension is circulated substantially without coming in contact with the anode; the particles may have a chance of colliding with substantially all surface areas of the working surface of the cathode, and are repeatedly brought in collision with the cathode at a velocity with a normal component of from 0.6 to 6.0 m/min.; and a particle concentration of the suspension at the time of collision is from 30 to 55% by volume. When such a stationary flow has been formed, a current for electroplating is caused to pass, whereupon deposition of metal on the particles proceeds without deposition of the particles and metal on the cathode.

This invention relates to a method for coloring stainless steel by controlling the potential difference between the surface of the stainless steel being colored and a reference electrode in a coloring liquor, characterized by differentiating a potential-time curve showing the variation with time of the potential difference between the surface of the stainless steel and the reference electrode by time to prepare the differentiation curve thereof and removing the stainless steel from the coloring liquor when the potential difference has changed from the coloring starting point that is the inflexion point on this differentiation curve, at which the variation amount of the potential per unit time changes from a falling tendency to a rising tendency, by a predetermined amount associated with the desired color.

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Chiba, Japan

Kiyoshi Takatsu