Abstract: A process for the preparation of lead molybdate pigments containing lead chromate, lead sulfate and lead molybdate, which comprises preparing the lead molybdate pigments by reacting an aqueous solution of a lead salt with an aqueous solution containing chromate, molybdate and sulfate salts or with an aqueous solution of each of said salts using 2 to 5 mol % of lead molybdate seed crystals, based on the total molar amount of lead chromate, lead sulfate and lead molybdate. The lead molybdate pigments so obtained are strong and are highly suitable for coloring organic materials of high molecular weight.
Type:
Grant
Filed:
October 17, 1988
Date of Patent:
April 16, 1991
Assignee:
Ciba-Geigy Corporation
Inventors:
Leonardus J. H. Erkens, Gerben P. Algra, Herman J. J. M. Geurts, Hubertus P. A. Gielkens
Abstract: This invention relates to iron-base alloy compositions, nickel containing austenitic ferrous alloy compositions (especially low nickel compositions) and dopants added to low nickel austenitic alloys as a means of improving the elevated temperature oxidation resistance of the resultant material.
Abstract: A ceramic-coated heat resisting alloy member comprises a base metal mainly composed of at least one of nickel, cobalt and iron; a mixture layer which is deposited on the external surface of the base metal and which comprises a ceramics and a metal; an alloy layer which is formed between the mixture layer and a ceramic coating layer formed as an outermost layer and which comprises an alloy material exhibiting excellent resistance to high temperature oxidation and excellent resistance to high temperature corrosion. It is therefore possible to prevent any high temperature oxidation and high temperature corrosion of the mixture layer and to enable the mixture layer to have a satisfactory function of reducing the thermal stress produced between the ceramic coating layer and the base metal. The ceramic coating thus has a satisfactory thermal barrier effect on the base metal.
Type:
Grant
Filed:
May 3, 1989
Date of Patent:
October 30, 1990
Assignees:
Hitachi, Ltd., The Tokyo Electric Power Company