20130216715 | PROCESS FOR PRODUCING A PROJECTION BLACKBOARD - A projection blackboard having both of an excellent blackboard function and an excellent screen function, and a process for producing the same. The surface enamel layer that is an outermost layer of the enamel layers is formed by using a enameling upper glaze wherein at least titanium oxide coated particles, or a titanium oxide glaze together therewith is blended into a transparent mat glaze, so as to render the layer an enamel layer having a predetermined color tone, a surface characteristic that the Rz is from 5 to 25 μm and a reflective characteristic that the peak gain is 0.28 or more, or having these properties and a glossiness Gs (75°) of 1 to 30%. This makes it possible to produce a blackboard excellent in both of blackboard function and screen function. The titanium oxide coated particles are preferably particles wherein surfaces of mica particles are coated with titanium oxide. | 08-22-2013 |