Patent ID: 8257980

Claim:
A sensory pigment for use in foods, packaging, pharmaceutical products, paper and electronic products, which comprises metallic, metal-containing carrier particles ( 1 ) or carrier particles ( 1 ) containing at least one metal-oxygen compound, with a size of the longer particle axis greater than 300 nm, wherein the carrier particles ( 1 ) comprise at least one layer of chromophoric particles ( 4 ) having a size of from 1 to 100 nm, and interposed between the carrier particles ( 1 ) and the layer(s) of chromophoric particles ( 4 ), a 5 to 500 nm thick layer of at least one chemically reactive (bio)organic or inorganic polymer ( 3 ), wherein a reaction of the polymer to an external chemical or physical stimulus causes a structural change in the polymer layer ( 3 ), which results in a change, visible to the human eye or measurable in the infrared range, in a color of the pigment by resonance-amplified optical absorption.