A process for producing continuous-filament casein yarn by pot-spinning is described. The fiber has a tensile strength of 1.0-1.2 grams per denier, elongation of 50 percent, excellent soft ness, and warmth. Fiber evaluation indices are presented.

Rayon monofilaments containing 80% activated carbon were prepared. They are an effective medium for adsorbing noxious odors. High grade gas‐adsorbing carbons are intimately bound in a cellulose matrix by niising the carbon in viscose ‘sodium cellulose xanthate solution’ and extruding the mixture through a special conjugate jet as iiioiiofilaments into a rayon coagulating bath. The special jet permits a backbone of plain viscose to be spun as a spine support for the carbon‐loaded portion of the monofilament to give it added strength. The diameters of the dry, nondusting monofils can be varied greatly. For air cleaning purposes the nonfilanients range from 1/64 to 3/64 in. in diameter. Although imbedded in cellulose, the carbon's capxity to remove malodors remains high. In addition, when made into a filter unit, the resistance to air flow through the unit is low. The novel use of regenerated cellulose as a carrier for large quantities of activated carbon indicatcs that other materials (catalysts, ion exchange resins, etc.) can be similarly bound in cellulose and still retain a high level of their original performance.

Casein fibers hardened with formaldehyde solutions need further processing to withstand boiling acid dye baths. Studies on desamination of casein fiber at various steps in the spinning process are reported. Desamination of casein fiber increases its resistance to dye baths. Desami nated fiber is given additional stability by treatment with acid-formaldehyde solutions followed by baking at 110°C. Dye uptake of both acidic and basic dyes is reduced by the combined treatment.

A method is described for reducing the rate of water uptake of casein fibers and plastics. The method involves treating formaldehyde-hardened casein products with resorcinol and formaldehyde, drying, and heating. Optimum conditions for this treatment are described. The results indicate that resorcinol forms crossbonds with casein and formaldehyde.