Patent · US Expired

Humidity indicators

US6927063B2 · kind B2 · utility

8Cited by
9References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 10, 2004
Grant dateAug 9, 2005
Priority date—
Expiry dateMay 10, 2024

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N31/222
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Silica-based carrier impregnated with iron(III) or iron(II) salts functions as a humidity indicator giving a yellow/amber to nearly colourless colour change as the carrier humidifies.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.