PROCESS IMPROVEMENT OF REACTIVE DYE SYNTHESIS USING SIX SIGMA CONCEPT

摘要

This research focuses on the problem occurred in the reactive dye synthesis process of a global manufacturer in Thailand which producing various chemicals for reactive dye products to supply global industries such as chemicals, textiles and garments. The product named "Reactive Blue Base" is selected in this study because it has highest demand and the current chemical yield shows a high variation, i.e. yield variation of 90.4%-99.1% (S.D. = 2.405 and Cpk =-0.08) and average yield is 94.5% (lower than the 95% standard set by the company). The Six Sigma concept is applied aiming at increasing yield and reducing variation of this process. This approach is suitable since it provides a systematic guideline with five improvement phases (DMAIC) to effectively tackle the problem and find the appropriate parameter settings of the process. Under the new parameter settings, the process yield variation is reduced to range between 96.5%-98.5% (S.D. = 0.525 and Cpk = 1.83) and the average yield is increased to 97.5% (higher than the 95% standard set by the company).