3m Innovative Properties Company

Minnesota Mining and Manufacturing Company

David M Read

Kevin D Landgrebe

Ranjani V Parthasarathy

Steven S Kirckof

David A Whitman

Anthony E Bennett

Chemical indicator compositions comprising a bismuth compound; elemental sulfur; and a compound with relatively high water solubility which makes the composition alkaline when exposed to water vapor at an elevated temperature; a chemical indicator comprising a substrate and the composition coated on at least a portion of a major surface of the substrate; and methods of making and using the chemical indicator are disclosed.

Chemical indicator compositions, indicators and methods

A chemical indicator composition comprising a bismuth (III) compound selected from the group consisting of bismuth (III) oxide and a bismuth (III) compound comprising at least one organic group which includes 2 to 20 carbon atoms; elemental sulfur; and a compound which makes the composition alkaline when exposed to water vapor at an elevated temperature; a chemical indicator composition comprising a bismuth (III) compound; elemental sulfur; a compound which makes the composition alkaline when exposed to water vapor at an elevated temperature; and at least one acid other than any acid present in the bismuth (III) compound; a chemical indicator comprising a substrate and the composition coated on at least a portion of a major surface of the substrate; methods of making the chemical indicator; and methods of using the chemical indicator are disclosed.

Chemical indicator composition, indicators and methods

The present invention provides a hydrogen peroxide indicator and a peracetic acid indicator that include a substrate on which is disposed an indicator composition that includes at least one of a select group of colorants and a transition metal salt. As a result of exposure to hydrogen peroxide and/or peracetic acid, the colorants change color, and even become colorless, thereby providing an indication of the presence of hydrogen peroxide and/or peracetic acid.

Hydrogen peroxide and peracetic acid indicators and methods

Peracetic acid indicators and methods of use

The present invention provides a hydrogen peroxide indicator that includes a substrate on which is disposed an indicator composition that includes at least one of a select group of colorants. As a result of contact with hydrogen peroxide, the colorants change color, and even become colorless, thereby providing an indication of the presence of hydrogen peroxide.

Hydrogen peroxide indicator and method

A steam sterilization indicator composition comprising a bismuth compound, a sulfur source, and a compound capable of generating alkaline conditions when exposed to steam; wherein when exposed to steam the composition noticeably changes color and when exposed to dry heat either does not change color or changes color to one that is markedly different from the color formed when the same composition is exposed to steam.

Growing community of inventors

White Bear Lake, MN, United States of America

David M Read