Chrome orange
Composition and Properties of Chrome Orange
Chrome orange is basic lead chromate with the chemical formula PbO • PbCrO4. It has the same chemical composition as chrome red, different shades of orange to red are due to different particle sizes. All chromates are affected by acids and alkalis. The basic character of this pigment makes it more resistant to alkalis and less resistant to acids than chrome yellow, it is also not very lightfast and darkens with age. It is compatible with all other pigments.
Names
Golden orange-yellow, chrome cinnabarPO 21, CI 77601After the element chromium, from Greek khrōma = color
Preparation
Attention: All chromates and dichromates are highly toxic chemicals and should not be used by people not trained to handle them.Basic lead chromate can be prepared by reaction of neutral lead chromate with alkalis.
History of Use
The French chemist Louis Vauquelin discovered the element chrome in 1797. Shortly after the possibility of using lead chromate as a pigment was recognized and the first methods of preparation were invented. The records of usage of chrome orange are rare.Examples of use
