XỬ LÝ TẨY TRẮNG VÁN BÓC GỖ KEO TAI TƯỢNG VÀ KEO LAI

Abstract

Acacia mangium and Acacia hybrid (Acacia mangium  Acacia auriculifomis) are the main raw materials being used in the peeling veneer production industry in Vietnam. Due to its structural characteristics, acacia wood has the quite difference between the heart wood and sap wood (both in colour and density of wood); The difference of colour, some what limited to the quality of veneer product to be used for plywood and multilaminar products manufacturing. Study on bleaching of peeled veneer of Acacia wood for the homogeneous coloration between the two parts of heart wood and sap wood will increase the value and usability of the acacia timber in the production of multilaminar products. The treatment results show that the treatment time and chemical concentration of (H2O2) have a great influence on the degree of bleaching. The result of bleaching will be better if the veneer is treated in the condition of chemical liquid having concentration (or solid content) is higher
or the treated time to be kept longer. The results also indicated that the minimum time at different chemical concentration for the homogeneous coloration between the two parts of heart wood and sap wood; Concentration of (H2O2) at 20%, the minimum time is 3 hours; Concentration of (H2O2) at 25%, the minimum time is 2 hours and at the Concentration of (H2O2) at 30%, the minimum time is 1 hour. This is the basis for selecting the suitable solution when it is needed to bleach colour or for the homogeneous coloration between
the heart wood and sap wood of veneer as well as before veneer colouring.