247 Somporn Chaiarrekij et al วารสารราชบัณฑิตยสถาน ปีที่ ๓๗ ฉบับที่ ๑ ม.ค.-มี.ค. ๒๕๕๕ cycles increases, their effects might be possibly detected. Increasing the percentage of kapok pulp used with the recycled pulp brought about higher opacity, density and tensile index but lower porosity, brightness and whiteness of the handsheets. Using a higher amount of softwood pulp led to higher tear index only. So, using the kapok pulp or softwood pulp or both with a proper amount of pulp is definitely dependent on the final paper properties required. Acknowledgement Financial support from the Thailand Research Fund (Research Grant Number: RTA5080004) is very grateful. Some research facilities provided by the Product and Development Center of the SGC Paper Public Company Limited were also thankful. Many thanks are due to the Department of Imaging Science and Technology for full support of research facilities. References 1) Xiao, H., Yu, W.-D., and Shi, M.-W. (2005). “Structure and performances of the kapok fiber,” Journal of Textile Research 26(4), 4-6. 2) Lim, T.-T., and Huang, X. (2007). “Evaluation of kapok ( Ceiba pentandra (L.) Gaertn.) as a natural hollow hydrophobic-oleophilic fibrous sorbent for oil spill cleanup,” Chemosphere 66, 955-963. 3) Huang, X. F., and Lim, T. T. (2006). “The performance and mechanism of hydrophobic–oleo - philic kapok filter for oil/water separation,” Desalination 190(1-3), 295-307. 4) Hori, K., Flavier, M. E., Kuga, S., Lam, T. B. T., and Liyama, K. (2000). “Excellent oil absor - bent kapok [ Ceiba pentandra (L.) Gaertn. ] fiber: Fiber structure, chemical characteristics, and application,” J. Wood Sci . 46(5), 401-404. 5) Chaiarrekij, S., Wongsaisuwan, U., and Watchanakit, S. (2008). “Papermaking from Kapok fiber,” Thai Petty Patent, 4279 , June 13, 2008. 6) Chaiarrekij, S., Apirakchaiskul, A., Suvarnakich, K., and Kiatkamjornwong, S. (2012). “Kapok I: Characteristics of Kapok Fiber as a Potential Pulp Source for Papermaking,” BioResources 7(1), 475-488.