water soluble farbmine or farbkreide and methods for their manufacture

摘要

A colour pencil or crayon based on a composition containing filler and pigment contains 1-30 wt.% polyvinyl alcohol (PVA) as binder and 1-25 wt.% monomeric polyalcohol and/or hydroxyethylated phosphoric ester as plasticiser. Also claimed is a method of making the pencils or crayons. Preferably the alcohol is glycerol, glycol, trimethylolpropane (TMP) or triethanolamine. An inorganic filler is used, especially kaolin, talc, steatite powder, calcium carbonate or titanium dioxide. The composition also contains lubricant(s). In particular, it contains 1-30, especially 5-15 wt.% PVA, 1-25 wt.% plasticiser, 10-75 wt.% filler, 1-25 wt.% lubricant, 2-20 wt.% colourant and 0.5-5 wt.% ancillaries, especially binder-modifier(s) selected from acrylic resins, urea-formaldehyde resins, melamine-formaldehyde resin, starch and casein.