Abstract
Particleboards were manufactured from high-moisture raw particles using a radio-frequency press which has both hot-press heating and radio-frequency heating, and the properties of the boards were analyzed. The pressing time was at least 8 min and the internal bond strength was 0.192 MPa when the boards were manufactured using only hot press heating without radio-frequency heating. However, a reduction in pressing time to just 3 min and an increase in internal bond strength to 0.440 MPa was possible when the board was manufactured using the radio-frequency press. Using the radio-frequency press caused the temperature of the inside of the boards to rise sharply and this resulted in a great reduction in pressing time and an increase in internal bond strength. Moreover, the pressing time was reduced to 2.5 min and the internal bond strength was increased to 0.552 MPa by installing an air-injection device on the radio-frequency press. Further reduction of pressing time and increase in internal bond strength were achieved by air injection. As a result, it was clarified that the internal bond strength of the boards could be achieved even when the binder resin content was reduced by approximately 25%.
