7-Benzothiazolesulfonic acid, 2,2'-[(2-sulfo-1,4-phenylene)bis[imino(1-acetyl-2-oxo-2,1-ethanediyl)-2,1-diazenediyl-4,1-phenylene]]bis[6-methyl-, compd. with α,α',α''-(nitrilotri-2,1-ethanediyl)tris[ω-hydroxypoly(oxy-1,2-ethanediyl)] (1:3)