Sterilization indicator

• US 2,798,855 A
• Filed: 03/19/1954
• Issued: 07/09/1957
• Est. Priority Date: 03/19/1954
• Status: Expired due to Term

• Current Assignee: John G. Hainsworth
• Original Assignee: John G. Hainsworth
• Inventors: Hainsworth, John G.
• Application Number:
  US03/417,491
• Time in Patent Office: 1,208 Days
• US Class Current: 436/1
• CPC Class Codes: G01N 31/226 for investigating the degree of sterilisation

Claims

1. AN ARTICLE HAVING APPLIED THERETO A STERILIZATION IN DICATOR COMPRISING, A COATING CONSISTING ESSENTIALLY OF A NON-REACTIVE, WATER-INSOLUBLE BUT PARTIALLY WATERL-PERMEABLE RESIN, A PARA-PHENYLENEDIAMINE HAVING AT LEAST ONE ACTIVE AMINO GROUP, AND A REACTANT FOR PRODUCING AN AZOMETHINE DYE WITH SAID PARA-PHENYLENEDIAMINE, SAID REACTANT BEING SELECTED FROM THE GROUP CONSISTING OF NAPHTHOLS, PHENOLS, PYRAZOLONES, AND ACETO ACETIC ESTERS AND DERIVATIVES THEREOF AN ACETO-ACETIC ACID LINKAGE, FOR EACH 100 PARTS BY WEIGHT OF RESIN THERE BEING EMPLOYED FROM 0.25 TO 25 PARTS BY WEIGHT OF SAID PARA-PHENYLENEDIAMINE, AND FROM 0.75 TO 75 PARTS BY WEIGHT OF SAID REACTANT FOR FORMING AZOMETHINE DYES THEREWITH, SAID DYE-FORMING CONSTITUENTS BEING PRESENTNT IN SUFFICIENT QUANTITY TO COLOR SAID COATING UPON EXPOSE TO STEAM UNDER STERILIZING CONDITIONS.