| 摘要 |
A wetness indicator including a pH indicating agent 4 may be a single layer or a multilayer composite. One or more layers of the composite may be used to promote or inhibit environmental fluid contact with the Ph indicating agent dispersed within at least a portion of a layer thickness. Fluid travel through the layer thickness may be achieved by layer microporosity and/or addition of fluid regulating additives to the layer. The layer or layers may be polymer layers, ink layers, fibrous layers or combinations thereof. Ink compositions for use making such indicators are also disclosed. |
