Patent ID: 6162531
Filing Date: 2000-12-19
Classification: C08K,C09D,C09J,Y10T

Abstract:
A marking instrument comprising a marking tip and a marking fluid, the marking fluid being applied to a surface when the marking tip is placed in contact with the surface, the marking instrument having an improved cap-off life and wherein the marking fluid comprises at least one volatile solvent and a waxy additive dissolved in the solvent at a level of between 0.05% and 25% by weight and at a level which is at least 20% of the amount required to form a saturated solution of the additive in the solvent at 20.degree. C., said waxy additive having a melting point of at least 40.degree. C. and being capable of forming a continuous solid skin over the surface of the marking fluid if a quantity of the marking fluid is held in an open vessel which permits solvent evaporation from the surface thereof, the additive being selected from the group consisting of poly(ethylene glycol) waxes, monocarboxylic aliphatic acids containing 12 to 22 carbon atoms, amides of the aforementioned aliphatic acids, solid esters of the aforementioned aliphatic acids, monohydric aliphatic alcohols containing 14 to 22 carbon atoms, cholesterol, distilled lanolin alcohols, and salts of monocarboxylic aliphatic acids containing 4 to 18 carbon atoms.