A method of manufacturing school crayons - two-colour crayons.

摘要

The proposed manufacturing method overcomes the disadvantages of the existing methods of manufacturing crayons for school boards. The proposed two-colour crayon with a base of crystalline calcium carbonate, whether coated with tallow or beef fat or not, has an advantage, practically and economically, compared to existing crayons for school boards or similar uses. It may be used by teachers, pupils and others.