nondispersed

Nondispersed describes a state in which no dispersion has occurred; as used in chemistry and materials science, it refers to substances or phases that do not form fine particles, droplets, or a continuous distribution within another medium. It contrasts with dispersed systems, such as suspensions, emulsions, or colloids, where a dispersed phase is distributed in a continuous phase.

In practical terms, a nondispersed material remains as a single, relatively large phase or as a coarse solid; in pigment and filler technology, nondispersed pigments exist as large aggregates and are not broken into primary particles; this affects properties like color strength, opacity, and stability.

In optical or instrumentation contexts, nondispersed can describe detectors or media that do not separate light into its spectral components; nondispersive infrared (NDIR) sensors are an example of a nondispersive approach to spectroscopy, measuring absorption at select wavelengths without dispersion.

The term is context-dependent, and its precise meaning can vary by discipline; care should be taken to interpret based on the described medium and phase behavior. See also dispersion (chemistry), colloid, suspension, emulsion, and dispersive spectroscopy for related concepts.