Chemical exposure indication device
AssigneeThe Boeing Company
InventorsCarl W. Beck, Rebecca L. Storey
Life of this patent
Estimating the term…
Abstract
A chemical exposure indication device is disclosed. The device is removably attachable to a structure and includes a substrate having a first surface and a second surface and an indicating layer overlying the first substrate surface. The indicating layer includes a coating material that is chemically reactive with a pre-determined chemical compound that is known to degrade the structure. When the coating material is exposed to that corrosive compound in a pre-determined level associated with degradation of a metallic structure, the coating material provides a visual indication of the presence of the corrosive compound.
Claims21
A method of monitoring an exposure of a metallic structure to a chemical compound that degrades the metallic structure, the method comprising:
- (a) attaching a chemical exposure indication device to the metallic structure, the device comprising:
- a substrate having a first surface and a second surface, wherein the substrate is constructed of a material selected from the group consisting of metallic, ceramic, polymeric, natural textile, and manufactured textile;
- an indicating layer disposed directly on top of the first surface of the substrate or disposed directly on top of an intermediate layer disposed in between the indicating layer and the first surface of the substrate;
- and
- means for removably attaching the device to the metallic structure on the second surface,
- wherein the indicating layer comprises a chemically reactive coating material configured to react with the chemical compound that degrades the metallic structure upon exposure to the chemical compound;
- wherein the chemically reactive coating material provides a visual indication of the presence of the chemical compound at the metallic structure to which the device is attached;
- and
- wherein the chemical exposure indication device is non-analytical;
- and
- (b) observing the visual indication of the presence of the chemical compound at the metallic structure before damage to the metallic structure occurs.
A method of monitoring an exposure of a polymeric structure to a chemical compound that corrodes the polymeric structure, the method comprising:
- (a) attaching a chemical exposure indication device to the polymeric structure, the device comprising:
- a substrate having a first surface and a second surface, the first surface disposed directly underneath the second surface, wherein the substrate is constructed of a material selected from the group consisting of metallic, ceramic, polymeric, natural textile, and manufactured textile;
- and
- means for attaching the second surface of the substrate to the polymeric structure while exposing the first surface to an environment,
- wherein the first surface includes an indicating layer of a chemically reactive coating material that changes color in the presence of the chemical compound which is configured to corrode the polymeric structure to provide a visual indication of the presence of the chemical compound at the polymeric structure to which the device is attached;
- wherein the degree of color change of the coating material, upon exposure to the chemical compound, correlates to the amount of the chemical compound in the environment;
- and
- wherein the device has an effective service period of at least one month in the absence of exposure to the chemical compound;
- and
- (b) observing the visual indication of the presence of the chemical compound at the polymeric structure before damage to the polymeric structure occurs.
A method of monitoring an exposure of a polymeric structure to a gas, the method comprising:
- (a) attaching a chemical exposure indication device to the polymeric structure, the device comprising:
- a foil tape having a first side over-coated with a layer of chemically reactive paint, and a second, opposite side having an adhesive disposed thereon,
- wherein the second, opposite side of the tape is attached to the polymeric structure and the paint on the first side of the tape is exposed to the environment;
- wherein the paint is configured to change color in the presence of the gas at the polymeric structure to which the device is attached, and wherein the gas degrades the polymeric structure upon exposure to the gas;
- wherein the device has an effective service period of at least one month in the absence of exposure to the gas;
- wherein the device is non-analytical;
- and
- wherein the device provides a visual indication of exposure to the gas;
- and
- (b) observing the visual indication of the presence of the gas at the polymeric structure before damage to the polymeric structure occurs.
Dependencies are inferred from the claim text.