| abstract |
The present invention is directed toward a residual life indicator. The residual life indicator comprises a solid, surface active, waterproof support medium (20) having a concentric pattern (30) imprinted thereon. The concentric pattern comprises a center pattern (40) and at least one outer pattern (50). An indicator dye spot (60) is disposed within the center pattern of the concentric patter. When the indicator dye is exposed to contaminants, the indicator dye spot visually moves toward the outer pattern. |