Bichromatic Powder
Definition
A two-component powder mixture containing both black and white particles that produce visible contrast on substrates of mixed or uncertain reflectance.
- Composition
- Black and white particle mixture
- Purpose
- Contrast on mixed or uncertain-reflectance surfaces
- Application
- Latent print powder development
- Alternative to
- Single-colour fingerprint powder
Common questions
When would an examiner choose bichromatic powder over plain black or white?+
On surfaces with patterned, multicoloured, or unknown backgrounds where neither a pure black nor pure white powder would reliably contrast against every part of the surface.
Does bichromatic powder work the same way as magnetic powder?+
No, the two properties are independent. A powder's colour composition determines visual contrast, while magnetic application is a separate delivery method, so bichromatic powders can be formulated as either magnetic or non-magnetic.
Related terms
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- Magnetic Powder
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