Abstract: Color is removed from polymeric material by a method which comprises contacting a dyed or pigmented polymer composition with a non-aqueous extraction solvent comprising a nitrogen containing organic base, an ammonium salt and an alkanol. The present method is readily applied to a process for recycling colored polyamide substrates such as dyed nylon fiber.

Abstract: Color is removed from polymeric material by a method which comprises contacting a dyed or pigmented polymer composition with a non-aqueous extraction solvent comprising a nitrogen containing organic base, an ammonium salt and an alkanol. The present method is readily applied to a process for recycling colored polyamide substrates such as dyed nylon fiber.

Abstract: An improved process for the preparation of optionally substituted 2-anilinoacridones from optionally substituted 2,5-dianilinoterephthalic acids, comprises:(a) cyclizing 2,5-dianilinoterephthalic acid to give an intermediate product mixture which contains a major portion of a 2-anilino-3-carboxyacridone and a minor portion of a quinacridone;(b) combining said intermediate product mixture with a solvent which dissolves the 2-anilino-3-carboxyacridone at elevated temperatures but does not dissolve the quinacridone;(c) decarboxylating the 2-anilino-3-carboxyacridone in the mixture from step (b) at elevated temperatures to yield a product slurry comprising a solid quinacridone and a 2-anilinoacridone dissolved in the solvent;(d) separating the solid quinacridone, the catalyst, and other solid impurities from the solvent, whereby a solution containing the dissolved 2-anilinoacridone is obtained; and(e) subsequently separating the dissolved 2-anilinoacridone from the solvent.