Moisture/wetness detecting method, moisture/wetness detecting label, articles with moisture/wetness detecting function, and detecting material and method

摘要

A method of detecting moisture or wetness which enables determination as to whether or not precision instruments or industrial products have undergone improper conditions, is described, which comprises: (i) use of a composite material which contains at least one water-soluble decoloring agent and at least one methine dye whose color disappears upon reaction with the decoloring agent in a state that the decoloring agent and the dye are spatially isolated from each other, and (ii) detection of a history of contact with moisture or water by disappearance of color from the composite material.