Method of producing a pearlescent basic lend carbonate pigment
Abstract
Abstract A pearlescent pigment consisting of hexagonal platelets of basic lead carbonate is produced by bubbling carbon dioxide gas into an aqueous solution of a basic lead salt which is derived from the reaction of lead monoxide with an acid. The acid that is reacted with the lead monoxide can be nitric acid, but more preferably will have the general formula: WHEREIN X is a member from the group consisting of hydrogen, methyl and halogen. Reaction of the carbon dioxide with the basic lead salt is carried out in the presence of dimethylsulfoxide (DMSO) which is dissolved in the aqueous reaction medium, thus facilitating control over the rate and extent of crystal initiation and growth. The resulting basic lead carbonate pigment can be incorporated into plastics, lacquers, and the like to provide articles having the appearance of natural pearl.
Inventors
- 👤 David R Meldrum
- 👤 Frank J Eckert
Bibliographic Details
Claims Analysis
Total Claims: 13References Cited (Backward Citations)
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