Verfahren zur Herstellung von verspinnbaren, Pigmente in feiner Verteilung enthaltenden linearen aromatischen Polyestern

• Main Authors: GRUSCHKE HANS, GERSTENBERG.. HELMUT, MEDEM HEINZ, GRUENEWALD KARL HEINZ
• Format: Patent
• Language: German
• Published: 25.07.1963
• Subjects: APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBONFILAMENTS; CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS,THREADS, FIBRES, BRISTLES OR RIBBONS; CHEMISTRY; COMPOSITIONS BASED THEREON; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; METALLURGY; NATURAL OR ARTIFICIAL THREADS OR FIBRES; ORGANIC MACROMOLECULAR COMPOUNDS; SPINNING; TEXTILES; THEIR PREPARATION OR CHEMICAL WORKING-UP; USE OF INORGANIC OR NON-MACROMOLECULAR ORGANIC SUBSTANCES ASCOMPOUNDING INGREDIENTS

In the pigmenting of fibre-forming polyesters of dihydric alcohols and aromatic or aliphatic dicarboxylic acids, there is used a pigment dispersion obtained by dispersing the pigment in part of the dihydric alcohol together with a dispersion agent obtained by condensing (a) an aromatic hydroxy compound and an o -sulphomethyl compound of formula R-CH2-SO3X where R is an aromatic residue and X is an alkali metal or (b) a naphthalene sulphonic acid and formaldehyde, followed by removing coarse particles (e.g. greater than 3m ) from the dispersion by centrifuging or sedimentation. The pigment dispersion is then introduced into (1) a mixture of the dihydric alcohol and the dicarboxylic acid (or ester thereof) and the mixture polycondensed or (2) a mixture obtained by heating polyethylene terephthalate waste with ethylene glycol (the mixture being filtered either before or after addition of the pigment dispersion) and the mixture polycondensed. Examples describe the preparation of polyethylene terephthalate pigmented with carbon black. Other polyesters referred to are polyethylene terephthalate in which all or part of the ethylene glycol is replaced by 1:3-propane- or 1:4-butanediol or in which part of the terephthalic acid is replaced by isophthalic or sebacic acid. Specifications 250,398 and 610,137 are referred to.