| abstract |
A sensor wipe, made in part by a hydroentangling or conforming process, includes fibers onto which an indicator dye is immobilized. The substrate may be used to make sensor wipes for testing surface conditions, including but not limited to pH or the presence of certain microbes. The indicator dye does not leach from the sensor wipe. The indicator dye may be reversible so that the sensor wipe can be reused prior to disposal. |