สำนักราชบัณฑิตยสภา

«“√ “√ √“™∫— ≥±‘ µ¬ ∂“π Usa Sangwatanaroj, et al. 147 ªï ∑’Ë ÛÚ ©∫— ∫∑’Ë Ò ¡.§.-¡’ .§. Úıı the degummed filaments lost 2.1- 3.2% weight after bleaching. The Chinese raw silk filaments and the degummed filaments lost the highest weight of 9.8% and 3.2%, respectively, compared with the loss of the local raw silk filaments (7.4-8%) and the degummed fila- ments (2.1-2.4%). The Chinese silk had a lower resistance to bleaching condition than the local silk. Again, there was no correla- tion between the reeling methods and the silk resistance to bleach- ing found in this study. All the silk fibers used in this study showed the same behavior as they were highly vulnerable to alkali, less to bleaching with an advantage of a great resistance to acid. In addition, no clear correla- tion was found between the reel- ing methods (by hand and by ma- chine) and the silk resistance to acid, alkali and the bleaching agent. Possible Applications for Silk Fabric Production, Dyeing and Printing The characterized data ob- tained by this work conform to the fundamental theory for silk testing properties. It is the first time that such a comparison of silk proper- ties reeled by hand and machine is performed. More characterization will be carried out for a complete data base for applications in silk industry. Based on this type of data, appropriate fiber properties from the reeling techniques can be ad- justed or modified to suit its par- ticular requirement in production of silk fiber. Additionally, a proper fiber selection in correlation with fabric and its color appearance, fabric and printed fabric perma- nence based on color properties of the outer and inner layer fibers, and performance and usability of fa- bric itself and printed fabrics based on denier, crystallinity, and relative density can be achieved. New fa- bric designs can be created upon weaving the outer-layer silk yarns having darker colors in combina- tion with the inner layer silk yarns containing lighter colors to re- sulting in a new unique, aesthetic appearance of stylist Thai silk clothing. Fiber characteristics such as homogeneity, denier, and liquid absorption of the fiber as the major influencing factors for fidelity, resolution, and dot gain of printed fabrics can be manipulated. Information on resistance to sun- light, bleaching agent and acid- base conditions can be a guideline for formulations of dyeing chem- istry, printing ink chemistry and detergent chemistry using high performance colorants to reduce damages upon exposure to these environments. Conclusions In this study, three Thai silk filaments reeled by hand and by machine were analyzed compara tively for various properties. It was found that the reeling method could affect significantly the silk properties such as whiteness, polypeptide chain orientation or birefringence, crystallinity, heat resistance or softening point, dyeability, and denier or fiber size. The machine reeling increased the silk whiteness, birefringence, crys- tallinity, and softening point while decreasing the silk denier and dyeability in comparison with the hand reeling. Acknowledgment This research is financially supported by the Research Team Promotion Grant, the Thailand Research Fund under the Grant Number RTA4780004 (Suda Kiatkamjornwong, Project Head). Research facilities are provided by Chulalongkorn University. The authors gratefully acknow- ledge these supports. References 1. Asakura T, Demura M, Uyama A, Ogawa K, Komatsu K, Nicholson LK, Cross TA. NMR Characteriza- tion of Silk Proteins. Silk Polymers, ACS Symposium Series, 1994; 544: 148-154. 2. Nakamura S, Magoshi J, Magoshi Y. Thermal Properties of Silk Pro- teins in Silkworms. Silk Polymers, ACS Symposium Series, 1994; 544: 211-221. 3. Annadurai V, Subramanyam G, Gopalkrishne URS, Somashekar R. Structure-Property Relation in Varieties of Silk Fibers. Journal of Applied Polymer Science 2001;