PURPOSE: To efficiently bleach veneer in parallel to the production of a decorative panel by applying a bleaching agent activated by heat to the surface of the veneer and performing the bleaching of the veneer by the bleaching agent in heating environment.
CONSTITUTION: Veneer is arranged on a base material through an adhesive and pressed under heating by a hot press to be bonded to the base material to obtain a decorative material. Alkaline aq. hydrogen peroxide is applied to the decorative material taken out of the hot press as a bleaching agent activated by heat by spraying. The coated decorative materials are laminated and the whole of them is covered with a sheet material to be kept. Ammonia water in aq. hydrogen peroxide functions as an activating aid activating the decomposition reaction of hydrogen peroxide to HOO- and H+. Therefore, after alkaline aq. hydrogen peroxide is applied, the bleaching action of the veneer is accelerated by the remaining heat of the hot press in a laminated state and, since the laminated decorative materials are covered with the sheet material, evaporation is prevented and good bleaching is performed.
IWASHITA NANA
KATAYAMA YOSHIHISA
KONDO HISATSUGU
