Flexible porous web having a permanent humidity sensor for indicating release of material therefrom
First Claim
1. A porous web having a permanent humidity detecting sensor comprisinga porous web having a substantially porous matrix and having bonded therein a metallic salt that undergoes a color change from its hydrated to its dehydrated state, said metallic salt bonded in said matrix with a polymeric binder that permanently bonds the salt in said matrix and allows the salt to undergo a visible color change upon a change in humidity of the environment to which it is exposed, said porous matrix containing an agent for release from the matrix, said release detected by a visual observation of said color change.
1 Assignment
0 Petitions
Accused Products
Abstract
A porous web having a permanent humidity detecting sensor is disclosed in which a metal salt is permanently bonded in the porous web matrix. The metal salt undergoes a color change from its hydrated to its dehydrated state to detect a change in humidity of a surrounding environment. Nonwoven fibrous webs having a permanent humidity detecting sensor are especially adapted for containing materials such as fabric softeners that may be released upon the conditions of a conventional clothes dryer for treatment of the clothes and visual detection of the release of softener by color change of the humidity sensor.
41 Citations
10 Claims
-
1. A porous web having a permanent humidity detecting sensor comprising
a porous web having a substantially porous matrix and having bonded therein a metallic salt that undergoes a color change from its hydrated to its dehydrated state, said metallic salt bonded in said matrix with a polymeric binder that permanently bonds the salt in said matrix and allows the salt to undergo a visible color change upon a change in humidity of the environment to which it is exposed, said porous matrix containing an agent for release from the matrix, said release detected by a visual observation of said color change.
-
9. A porous web having a permanent humidity detecting sensor comprising
a nonwoven porous web of staple fibers having a substantially porous matrix and having bonded therein a metallic salt that undergoes a color change from its hydrated to its dehydrated state, said porous matrix having a void volume of about 40 to about 90%, said metallic salt bonded in said matrix with a polymeric binder that permanently bonds the fibers and the salt in said matrix and allows the salt to undergo a visible color change upon a change in humidity of the environment to which it is exposed, said porous matrix containing an agent for release from the matrix, said release detected by a visual observation of said color change, said polymeric binder and metal salt are derived from an aqueous mixture of a polymeric emulsion containing the metallic salt.
Specification