摘要 |
A writing liquid is formed from a solvent for an organic styrene resin pigment in combination with a chlorofluoroalkane of from 1 to 3 carbon atoms. The potential toxicity of the solvent (or solvent vapors) is eliminated and writing speeds of the writing liquid are improved by the addition of the chlorofluoroalkane. The writing liquid is used for transparentizing an opaque layer of an organic styrene resin pigment, uniformly distributed as fine particles in a film-forming binder carried on a transparent or opaque support. When the writing liquid is applied to the opaque layer using a suitable writing instrument, such as a pen, the opaque layer immediately becomes transparent where it is contacted with the solvent.
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