Freeze monitoring device

摘要: A device composed of (1) a color changing indicator, (2) an optional polymeric binder, preferably having gel forming capability, and (3) activator solvent system which induces change in the indicator when is frozen, region about 0 to −30° C. An example fine dispersion partially polymerized diacetylene formula: R—C≡C—C≡C—R, where R substituent group, e.g., 4BCMU R═—(CH 2 )OCONHCH COO(CH ) 4 H, dispersed mixture solvents, 96:4 water:ED (ethylene glycol diacetate), with or without binder. When temperature lowered freezing point water, phase separates out indicator. The can undergo irreversible change, from blue red, frozen made above be used as freeze for monitoring undesirable materials, such emulsions, latex paints, produce foods, flowers, sea vaccines require monitoring.