Patent GB-508803-A (GB)
Title: Manufacture of new coloured condensation products
IPC: C09B23/14
Filed: 1938-01-05
Abstract: 508,803. Dyes; dyeing; synthetic resin compositions. SOC. OF CHEMICAL INDUSTRY IN BASLE. Jan. 5, 1938, Nos. 316 and 317. Convention dates, Jan. 9, 1937 and Dec. 6, 1937. [Classes 2 (iii) and 15 (ii)] Coloured condensation products are manufactured by condensing a. compound of the general formula - Aryl-N(X)--CO-CH2CN, where X is hydrogen, an alkyl group or a hydroxyalkyl group which may be etherified or esterified, and Aryl is a benzene residue which may contain substituents, with an aldehyde of the general formula where R1 is an alkyl group and R2 is an etherified or esterified hydroxyalkyl group, or with a benzylidene compound of such an aldehyde with an aromatic aminosulphonic acid. Suitable starting materials are, on the one hand, cyanacetic acid anilide, o-, m- or p-toluidide, m-xylidide, o- or p-anisidide, p-cresidide, monomethyl- or monoethylanilide, hydroxyethylanilide, acetoxyethylanilide and methoxyethylanilide ; and, on the other hand, N-alkyl-N- alkoxyalkyl - p - aminobenzaldehydes, e.g. the N-methyl- and N-ethyl-N-methoxyethyl compounds, N-alkyl-N-acyloxyalkyl-p-aminobenzaldehydes, e.g. the N-methyl- and N-ethyl-N- acetoxyethyl compounds, and N-alkyl-N-sulphato -oxyalkyl -p -aminobenzaldehydes. - The products may be used for colouring lacquers containing natural or artificial resins, nitrocellulose or cellulose acetate, for colouring artificial materials, e.g. phenol- or urea.formaldehyde condensation products, or for dyeing cellulose esters and ethers, e.g. acetate artificial silk. In examples : (1) cyanacetic anilide is heated with N-ethyl-N-methoxyethyl-p-aminobenzaldehyde in alcohol in the presence of a base, e.g. piperidine or some alkali or sodium alcoholate; the product, when brought into a suitable state of subdivision, e.g. by grinding with a dispersing agent, such as sulphite cellulose liquor or the sulphonated residues of benzaldehyde manufacture, and water, dyes acetate artificial silk green-yellow shades ; the aldehyde may be replaced by its benzylidene compound with an aromatic aminosulphonic. acid, and the cyanacetic anilide by the ethyl- or hydroxyethylanilide ; (2) cyanacetic oanisidide is heated with N-ethyl-N-methoxyethyl-p-aminobenzaldehyde in alcohol in the presence of piperidine; the product dyes acetate artificial silk green-yellow shades ; the aldehyde may be replaced by its benzylidene compound with metanilic acid, in which case the reaction may be effected in aqueous solution, or by N-methyl-N-methoxyethyl-p-aminobenzaldehyde, and the cyanacetic o-anisidide by the p-anisidide, p-cresidide or m-toluidide; (3) the product of (2) from cyanacetic acid o-anisidide and N - ethyl - N - methoxyethyl-paminobenzaldehyde is dispersed in water, e.g. with the aid of turkey red oil or sulphite cellulose liquor, and acetate artificial silk yarn is dyed in the resulting bath. Cyanoacetic acid arylides of the general formula given above are obtainable by heating cyanoacetic acid methyl or ethyl ester with the appropriate aromatic amines. p-Aminobenzaldehyde derivatives of the general formula given above are obtainable by stirring the appropriate tertiary aromatic amine in the presence of formaldehyde and a nitrobenzenesulphonic acid in aqueous sulphuric acid solution with powdered iron at 30-50 C., and splitting the resulting azomethine compound with dilute alkalies. The Specification as open to inspection under Sect. 91 comprises the use of p-aminobenzaldehyde derivatives of the general formula given above in which R1 is alkyl or an alkyl residue containing as substituent at least one hydroxy group or etherified hydroxy group or hydroxy group esterified with an organic or inorganic acid and R2 is an alkyl residue substituted in the same way, additional starting materials specified being N-alkyl-N-hydroxyalkylaminobenzaldehydes, e.g. N-methyl or ethyl-N-hydroxyethyl - p - aminobenzaldehyde, N - di - (hydroxyalkyl) - -p - - aminobenzaldehydes, and N - hydroxyalkyl - N - alkoxyalkyl -p - amino - benzaldehydes, e.g. the N-hydroxyethyl-N- methoxyethyl compound. Reference is made to the use in example (2) above of N-ethyl-N- hydroxyethylaminobenzaldehyde. The products may be converted by the action of sulphuric acid into their sulphuric esters, which may be used for dyeing and printing acetate artificial silk. 'This subject-matter does not appear in the Specification as accepted.