Patent GB-860443-A (GB)
Title: Conjugated artificial filaments
IPC: C01B31/08
Filed: 1957-05-16
Abstract: <PICT:0860443/IV (a)/1> <PICT:0860443/IV (a)/2> <PICT:0860443/IV (a)/3> <PICT:0860443/IV (a)/4> A conjugate artificial filament, of at least two components, with an exposed component containing a major proportion of carbon is made by extruding two spinning solutions or melts, one of which contains dispersed carbon, from a common orifice. A carbon-containing component may be extruded annularly around a non-pigmented component, or the components may be in side-by-side relationship.  Filaments may be wet-, dry-, or melt-spun, as appropriate, from viscose, cellulose esters and ethers, acrylic resins, vinyl ester and ether polymers, vinylidene halides, polyethylene and polypropylene, polyamides and polyesters. Spinnerets as shown in Figs. 2 and may be used in making filaments as shown in Figs. 3 and 5 respectively.  Alternatively, a trisected spinneret may be used in which the plain material is extruded through the centre and the pigmented material on each side.  In the case of viscose, a T-fitting behind an extrusion orifice, in which pigmented and unpigmented viscose streams are mixed, may also be used, or a ring-core filament as in Fig. 5 may be made using the spinneret of Fig. 2 by using a young viscose as the plain component and an older viscose as the pigmented component, so that, owing to the greater shrinkage on spinning of the young viscose, the carbon-loaded portion spreads and encircles the plain portion.  Preferably, filaments are made by wet-spinning viscose, a plain viscose stream being supplied to channels 10 of the spinnerets shown, while a second stream of the same viscose is blended with an aqueous dispersion of activated carbon and this pigmented viscose is supplied to channel 7 of the spinnerets. After coagulation in a conventional bath the filaments may be stretched, and are collected in an acid regenerating bath, and subsequently washed and dried.  The filaments, which are suitable for use in adsorption and decolorization processes, preferably contain 80-90% by weight of carbon, based on the weight of the filament. Specification 579,081 is referred to.ALSO:<PICT:0860443/III/1> <PICT:0860443/III/2> A gas-adsorbent material consists of a conjugate artificial filament, of at least two components, with an exposed component containing a major proportion of carbon.  Filaments may be of the ring-core type, as in Fig. 5, the carbon-loaded component being outermost, or of the Siamese-twin type, as in Fig. 3, or may be tripartate, having a central plain portion flanked by two carbon-loaded portions (not shown).  The filaments preferably contain 80-90% by weight of carbon, based on the weight of the filament, and desirably are made from regenerated cellulose, but may also be made from cellulose esters and ethers, acrylic resins, vinyl ester and ether polymers, vinylidene halides, polyethylene and polypropylene, polyamides and polyesters.  The adsorbent power and effective life of the filaments, compared with conventional filaments containing substantially the same proportion of carbon, is determined by passing a stream of air containing carbon tetrachloride vapour through a bed of each filament.  Specification 579,087 is referred to.