SURFACE CHARACTERISTICS OF CCA TREATED SCOTS PINE AFTER ACCELERATED WEATHERING

Abstract

Some surface characteristics such as surface hardness, gloss, and colour characteristics of wood treated with CCA (chromated copper arsenate) after accelerated weathering were investigated. Wood specimens were prepared from air-dried sapwood of Scots pine (Pinus sylvestris L.). Before tests, wood specimens were impregnated with 6.25, 12.50, and 25.00 percent aqueous solutions of CCA. The results showed that CCA treatment caused increases in gloss and surface hardness of Scots pine after accelerated weathering. While the decrease in L* values of Scots pine indicates that the specimens became darker, positive values of Delta a* and Delta b* indicate a tendency in wood surface to become reddish and yellow, respectively. Total changes in colour (Delta E*) exhibited a systematic trend to higher values with increasing accelerated weathering time. Delta E* of CCA treated Scots pine was lower than untreated Scots pine. Generally, surface characteristics of CCA treated Scots pine gave better results than untreated Scots pine after accelerated weathering.