Patent GB-344057-A (GB)
Title: Manufacture of vat-dyestuffs or intermediate products of the benzanthrone-pyrazolanthrone series
IPC: B21D3/05
Filed: 1929-12-02
Abstract: Benzanthrone-pyrazolanthrones.-Vat dyes or intermediate products are obtained by reaction between an amino-Bz1-Py 1/-2 : 21-benzanthronepyrazolanthrone and a compound capable of reacting with hydrogen atoms attached to a nitrogen atom, other than a negatively substituted dibenzanthrone or isodibenzanthrone.  The reaction may be carried out in a solvent in the presence of an acidbinding agent and a copper catalyst, such as copper carbonate, copper acetate or cuprous chloride.  The aminobenzanthronepyrazolanthrones used as parent materials may be obtained synthetically by the process of Specification 298,284, [Class 2 (iii), Dyes &c.], or by nitrating and reducing the Bz1-Py 1/-2 : 21 - benzanthronepyrazolanthrones.  In examples, the aminobenzanthronepyrazolanthrone obtained by nitration and reduction of Bz1-Py 1/-2 : 21-benzanthronepyrazolanthrone is (1) acetylated with acetic anhydride in nitrobenzene, or benzoylated with benzoyl chloride in nitrobenzene; the products dye cotton in greenish-blue tints, (2) condensed with cyanuric chloride in nitrobenzene in the presence of cuprous chloride; the product dyes bluish-green tints, which become more turbid when after-treated with hypochlorite, (3) methylated by treating with dimethyl sulphate in nitrobenzene with addition of trisodium phosphate; the product dyes green tints, (4) condensed with benzyl chloride in nitrobenzene; the product dyes greyish-green tints, (5) condensed with 1-chloranthraquinone or 1 : 5-dichloranthraquinone in nitrobenzene, in the presence of sodium acetate and copper acetate or copper carbonate; the products dye in greenish-grey tints, (6) condensed with brombenzanthronepyrazolanthrone (obtained by condensing pyrazolanthrone with dibrombenzanthrone of M. Pt. 256 DEG  C. by the process of Specification 298,775, [Class 2 (iii), Dyes &c.], and fusing the monobrom-Bz1-benzanthronyl-Py 1-pyrazolanthrone thus obtained with caustic potash by the process of Specification 298,284 in nitrobenzene, with addition of sodium acetate and copper carbonate to give a product dyeing in bluish-grey shades; a similar product is obtained by replacing the aminobenzanthronepyrazolanthrone obtained by nitration and reduction by the synthetic product made by condensing pyrazolanthrone with nitrated Bz1-brombenzanthrone, reducing and fusing with caustic potash, (7) condensed with dichlorbenzanthronepyrazolanthrone (example 7 of Specification 298,284, [Class 2 (iii), Dyes &c.], either one or two molecular proportions of the amino compound being used for each molecular proportion of the chlor compound; the products dye in bluish-grey shades, (8) condensed with a hexachlorbenzanthronepyrazolanthrone, (obtained by chlorination in chlorsulphoric acid in presence of iodine); the product dyes olive-grey shades, (9) condensed with monochlorbenzanthronepyrazolanthrone (made by chlorinating in nitrobenzene) to give a product dyeing in deep grey shades, (10) condensed with 1-aminoanthraquinone-2-aldehyde in nitrobenzene; the resulting azomethine is unstable in an alkaline hydrosulphite vat but is a useful intermediate product, and (11) condensed with 1 : 4-naphthoquinone in nitrobenzene; the product dyes greyish-green tints.