天然彩棉与染色棉的鉴别

The identification of Natural colored cotton and dyeing cotton

为了解决市面上存在用染色棉冒充天然彩棉的突出问题。本文尝试研究天然彩棉与染色棉的鉴别方法,通过实验,主要分析了pH值对天然彩棉颜色和色素提取液的影响,得出天然棕棉的颜色在酸性条件下向黄绿方向变化,在碱性条件下向黄红方向变化,但染色棕棉的颜色受酸碱性的影响很小;天然彩棉色素提取液吸光度随着pH值的变化而呈现有规律的变化,而染色棕棉色素提取液吸光度不随着pH值的变化而变化。因此可采用pH值对天然彩棉颜色影响和棉纤维色素提取液的酸碱可逆色变反应两种方法鉴别天然棕色棉和染色棕棉,方法简单快捷有效。

In order to solve the outstanding problems about the dyed cotton as copycat packaging exist in market consequent, this paper tried to study the identification of natural colored cotton and dyed cotton. Through experiment, we analyzed the effects of the pH value on natural cotton in color and pigment extract＇s. We gained the following conclusions： under acidic conditions, natural colored brown cotton will be likely to change to yellow-green. In alkaline conditions, the direction will be yellow and red; acidic and alkaline has a small impact on dyed cotton in color. Natural colored cotton pigment extract＇s absorbance have regular changes with the change of pH value. But the dyed brown cotton＇s pigment extracrs absorbance have no changes with the change of pH value. So we learned using the effects of the pH value on natural cotton in color and pigment extracting from cotton fibers＇ acid-base reversible reaction to identify the natural brown cotton and dyed brown cotton, the method is simple and efficient and effective.