| 摘要 |
1336799 Bleaching BADISCHE ANILIN & SODA FABRIK AG 11 Aug 1971 [12 Aug 1970] 37677/71 Heading D1P Fibrous material based on amide, group containing constituents e.g. wool, silk, bristles, polycaprolactam and polyhexamethylene adipamide is bleached by treatment with an aqueous solution of the zinc salt of hydroxymethane sulphinic acid and a complexing agent e.g. the sodium salts of EDTA and nitrilotriacetic acid and polymeric phosphates at 70-100‹C and p.H 2-4. The aqueous solution may contain formaldehyde, trioxane, paraformaldehyde and hexamethylene tetramine as stabilizer. The p.H is adjusted with formic, acetic, sulphuric or phosphoric acid. |
