| 摘要 |
<p>PURPOSE:To obtain the title composition which is free of problems of toxicity and odor and can give an easily erasable writing by mixing water with a colorant, a specified room temperature film-forming resin and a specified release agent. CONSTITUTION:Water as a solvent is mixed with a colorant dissolved or dispersed in water (e.g., carbon black dispersed with the aid of a dispersant of an ammonium salt of a styrene/butyl acrylate/methacrylic acid copolymer), at least one room temperature film-forming resin selected from an emulsion or hydrogel of polyvinyl acetate, a vinyl acetate copolymer, an alkyd resin or a urethane resin and a water-solubilized vinyl acetate copolymer, alkyd resin and a urethane resin (e.g., a hydrosol of a vinyl acetate/ethyl acrylate/ acrylic acid copolymer) and a release agent which is at least one difficulty volatile liquid compound selected from among an aliphatic carboxylic ester, a higher hydrocarbon and a higher alcohol each of which is normally liquid (e.g., butyl stearate).</p> |
