| 摘要 |
1485846 Food colourings DYNAPOL 19 Nov 1974 [30 Nov 1973] 50124/74 Heading C3P [Also in Divisions A2 and C6] Non-toxic food colourings have the general structure M-(NR-SO 2 -K) z in which M is a non-degradable, non-digestable organic polymer backbone of M.W. at least 10,000 and of such molecular dimensions that the colouring does not pass through the mucosa of the gastrointestinal tract, K is an optically chromophore group, z is a positive integer, R is H or a C 1-6 hydrocarbon group, and NR-SO 2 is a sulphonamido group linking M to K and which is oriented with its NR group pendant from, but attached to, M. In the examples, the polymer backbone is derived from polyacrylic acid, and the following reaction sequence is used: (i) polyacrylic acid is treated with hydrazoic acid to effect, via the Schmidt rearrangement, production of an acrylic acid/vinyl amine copolymer, which is (ii) reacted with either N-acetylsulphanilyl chloride or 4-acetamido-1-naphthalene sulphonyl chloride, the product being (iii) hydrolysed to release free amine groups, (iv) diazotized, and (v) linked with a colouring substance selected from the following: Schaeffer's salt (orange), Pyrazolone T (yelloworange), 2-naphthol-3,6-disulphonic acid (red) or 1,8 - dihydroxynaphthalene - 3,6 - disulphonic acid (deep violet). |
