Educational toy for teaching colour - uses metal foil covered plate which reacts to chemicals discharged from containers

摘要

The educational display for teaching colour values to children has a transparent plastics film mounted on a stiff plastics baking layer. Between them is a metal foil covering the backing layer which reacts to various chemical substances to change colour. These substances are housed in containers which are burst under pressure to spread on the metal foil. The finger or a spreading instrument can be used.