Study on enhancing colour appearances and chemical compositions of 14 year-old cultivated Acacia Hybrid through oil-heat treatment process

• Main Author: Izyan Khalid
• Format: Thesis
• Language: English; English
• Published: 2009
• Subjects: TS920-937 Chemical processing of wood
• Online Access: https://eprints.ums.edu.my/id/eprint/38171/1/24%20PAGES.pdf; https://eprints.ums.edu.my/id/eprint/38171/2/FULLTEXT.pdf; https://eprints.ums.edu.my/id/eprint/38171/

This study investigated the effect of an oil heat treatment process on the colour appearances of 14 year-old cultivated acacia hybrid. The effects of parameters such as temperatures and duration of treatments are taken in consideration due to their influences in enhancing the colour of the wood from the sapwood right through the heartwood. Natural and untreated acacia hybrid normally had the sapwood having lighter colour than the dark colour heartwood. Turning these timbers into plywood or furniture at this stage will result in uneven colour as the results of the mixture between the sapwood and heartwood. This will decrease the aesthetic value of the product. Heating the wood at varying temperatures and durations would enhance the colour appearance of the wood. The colour changes in the sapwood and heartwood were measured using Minolta Chroma-meter CR-310 and the results were presented according to the CIE L *a*b* a colour co-ordinates system. The results revealed that the rising temperature at certain duration resulted in darkening of wood tissues. The decreased of L * values caused the darkening of the wood surfaces while the increase values in a* caused the wood colour becomes redder and decrease in b* values caused the decrease yellow colour of acacia wood. The difference of chemical composition in wood probably is the main reason for dissimilar in colour. This study showed features change in the chemical composition of acacia wood. The degradation in chemical composition was recognized when acacia woods were exposed to oil-heat treatment process. Holocellulose, hemicellulose and cellulose degraded with the increasing of treatment temperature and time of heating exposure. These studies recommend oil-heat treatment technology can be used in wood industry to modify acquiring darker tonality of wood to suit the customer demand.