摘要 |
<p>Process for removing color-formers from polymeric sulfonated phenol-formaldehyde condensation products so as provide condensation products having reduced tendencies to turn yellow and which provide stain-resistance to polyamide textile substrates which comprises dissolving a polymeric sulfonated phenol-formaldehyde condensation product in an aqueous base, acidifying the resulting aqueous solution so as to form a slurry, heating the slurry so as to form a two-phase system comprising an aqueous solution and a water-insoluble taffy-like material, separating the aqueous solution and the water-insoluble material from one another, and dissolving the water-insoluble material in an aqueous base.</p> |