Solvatochromic visual indicator and the use of the same
View Patent ↗A graphic and/or message display system is described. The graphic and/or message display system functions to develop over a period of time a hidden graphic or message on an indicator panel or display area. The hidden graphic or message is revealed when an obscuring graphic reacts with a solvent to change color become at least substantially transparent. The graphic and/or message display system may be used as a stand-alone device or may be incorporated as part of various articles or products, for instance, as a positive reinforcement or a reminder to perform a task. Methods for using the graphic and/or message display system are also described.
1. A visual indicator system comprising an indicator panel having a graphic region with a hidden message graphic and a masking graphic comprising a solvatochromic dye, and a solvent applicator comprising a substantially transparent sheet-like substrate having first and second surfaces, and a solvent disposed on the first surface of the substrate between the substrate and the masking graphic, the size of the sheet-like substrate corresponding to the size of the masking graphic.
2. The visual indicator system according to claim 1 , wherein the visual indicator system is a glove.
3. The visual indicator system according to claim 1 , wherein the indicator panel is either a substantially two-dimensional visual display or is part of a three-dimensional shaped surface or article.
4. The visual indicator system according to claim 1 , wherein the solvent is a fluid.
5. The visual indicator system according to claim 4 , wherein the fluid is a liquid, a gel, or a semi-solid.
6. The visual indicator system according to claim 1 , wherein the solvatochromic dye is a zwitterionic chromogen.
7. The visual indicator system according to claim 6 , wherein the zwitterionic chromogen is Reichardt's dye.
8. The visual indicator system according to claim 1 , wherein the solvatochromic dye is a merocyanine.
9. The visual indicator system according to claim 1 , wherein the solvatochromic dye comprises a compound having the formula
wherein R 1 , R 2 , R 3 , R 4 , and R 5 are selected from the group consisting of phenyl, benzyl, pyridinyl, aryl, heteroaryl, alkyl (C 1 -C 12 ), cycloalkyl, heterocyclo, halide, chlorine, fluorine, hydrogen, amido, amine, and thiol groups.
10. The visual indicator system according to claim 1 , wherein the masking graphic is colored.
11. The visual indicator system according to claim 1 , wherein the message graphic is colored.
12. The visual indicator system according to claim 1 , wherein the masking graphic and the message graphic are differently colored.
13. The visual indicator system according to claim 1 , wherein the indicator panel is activated when the solvent on the solvent applicator is placed against the indicator panel, establishing controlled communication between the solvent and the masking graphic.
14. The visual indicator system according to claim 1 , wherein the indicator panel is either a stand alone article in the personal care article or can be incorporated as part of a component of the personal care article.