Manufacturing Method for Ocher Board

PURPOSE : Provided is a manufacturing method of lightweight yellow earth boards with improved strength and adhesion compared with a conventional yellow earth products by adding cotton yarn and rubber tree sap to board materials comprising yellow earth, fly ash and gypsum. CONSTITUTION : The yellow earth boards are manufactured by the following steps of : mixing 40-60wt.% of yellow earth powder, 20-30wt.% of fly ash and 7-8wt.% of gypsum; putting 3-10wt.% of cotton yarn(15) onto mixtures carried by a conveyor belt(20), and mixing together; mixing 15-25wt.% of rubber tree sap(latex) with mixtures in a ratio mixtures to rubber sap of 7 : 3, wherein the rubber tree sap is diluted with water at a ratio of 50 : 50; forming mixtures into a board shape, and pressing the board covered with a net made of hemp on its upper side and a silver paper on its lower side to get boards having an effective thickness, wherein the net improves tensile strength and prevents bending of boards, and the silver paper improves heat insulation and prevents moisture; cutting yellow earth boards; drying boards at 30deg.C. © KIPO 2005