Degumming process is a fundamental process for silk yarn and silk fabric finishing. The main objective is scouring the substrate such as silk gum (sericin) wax and fatty acid from silk fiber. The principle of degumming process is breaking the peptide linkage of amino acid in sericin structure into a small molecule which is soluble in water. The hydrolysis reaction is performed by acid and alkaline but they have a big problem on the surface area of silk. Proteolytic enzyme is used to solve this problem but it has some disvantages such as using a specific condition and high price. For this reason papain enzyme form dry latex of Carica papaya Linn. is choren to degum the raw silk. Papain is an enzyme which has a good protein digestion. The efficiency of degumming process was evaluated by determination of tensile strength and staining test with direct dyes (C.I. Direct Red 80). The result revealed that the appropriate conditions for silk degumming with dry Carica papaya Linn.๛s latex should be recommended as follows: the amount of dry latex solution of 4% owf at 75 ฐC for 30 minutes at neutral condition (pH ≈7). The degummed fibers had lustrous soft and smooth surface. The fiber strength and surface were not damaged on this process.

This research was concerned with dye extraction from the bark of eucalyptus and application for silk and cotton fabric dyeing. Silk and cotton fabrics were treated with premordanting process before dyeing experiments in order to facilitate dye absorbency of fabrics such as silk dyeing at 90ฐC for 40 minutes and pH 4 cotton dyeing at 60ฐC for 40 minutes and pH no adjustment. The best result was achieved when liquor ratio between fabric and dyed solution as 1:30 was employed. Silk dyed in the solution extracting from the bark of eucalyptus with mordant compound displayed yellow to brown colour except fabric using fesrrous (Fe) mordant exhibiting the shade of dark brown to grey. For cotton fabric the shade of yellow to orange was obtained except fabric using ferrous (Fe) mordant displaying the shade of pale grey to gray. Silk and cotton fabrics treated with pre-mordanted and dyeing process has presented the properties of colour fastness to washing water and perspiration from good to very good level whereas colour fastness to light and rubbing was from fair to good level.