This is a necessary step because some of the starch degradation products in the presence of the sodium hydroxide used in scouring form strong reducing agents that can cause color changes in dyed materials.

• 此阶段很重要,这是因为降解淀粉的产物遇到在煮练中使用的氢氧化钠时,会形成还原剂,还原剂会使染色的织物褪色。