... educational products,such as interactive whiteboard and water-soluble chalks.with few of chemical doctors, who ... in terms of design and manufacture of water soluble chalk.It is patented products,The features ... Not to generate any chalk dust, and can create 100% dustless classroom,3, Can write on wet & ... to get the specifications of such products:Water soluble chalks: non-dust,non-toxic and non-smellchalk ...