2012 年 53 巻 620 号 p. 826-830
Various global environmental problems are caused by the volume consumption of fossil resources. As a solution to these problems, the development of wood plastic composites (WPC) and natural fiber reinforced plastics (NFRP) as substitutes for oil-based plastic is being furthered. However, the investigation of the environment resistance of injection molding products made from only wood-based material as a basic study of WPC and NFRP has not been carried out. In this study, a basic examination of resistance to water, heat-drying and light was performed on injection molding products made from only steamed bamboo powder. The results show that the products did not deteriorate after soaking in water for two weeks. Sectional area and weight increased after soaking in water, but they decreased by more than 10% after air-drying. Vickers hardness decreased after soaking in water, but it recovered after air-drying. Heat-drying at 80℃ for two weeks did not change the appearance of the products markedly. However, shrinkage between 4% and 8% was observed and weight decreased by about 5%. On the other hand, Vickers hardness and bending strength increased. By irradiation with ultraviolet rays, the color and shape of the products did not change markedly, but brightness markedly increased.