Development of yellow colour in pale colours when subjected to heat and/or light. When overcured for long periods or excessively high temperatures white powder coatings will darken or "yellow".

当涂层受热和/或光线照射下变化的趋势，长时间在较高的温度下，白色粉末涂料会变暗或发黄。

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Dispersing agent NNO Naphthalene sulphonate formaldehyde condensate This product is light yellow to yellow-brown powder, an anion surface active agent.

甲醛缩合物本品为浅黄色至黄棕色粉末，属阴离子型表面活性剂。

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