COLOUR CHANGE INDICATOR INKS AND COATINGS FOR STERILISATION PROCESSES

摘要

1458553 Indicator inks JOHN DICKINSON & CO Ltd 11 April 1975 [11 April 1974] 16247/74 Headings C3P and C3F An indicator ink comprises a solution in an organic solvent of an acid-free resin binder containing a finely divided metallic carbonate which is capable of decomposing with a change of colour to the naked eye when heated in contact with steam under pressure but which is stable to dry heat at 120-145‹ C. Suitable carbonates are basic copper carbonate, bismuth oxycarbonate, cobalt carbonate, basic cobalt carbonate, ferrous carbonate, basic lead carbonate and manganese carbonate and exemplified resins are ethyl cellulose, polybutyl methacrylate and petroleum resin.