Abstract: A process for producing a cellulose ester support is described which comprises producing said support from an organic solvent solution of a cellulose ester containing 30 ppm or less alkaline earth metal.

Abstract: A process for preparing porous, spherical cellulose particles which comprises suspending a cellulose organic ester solution dissolved in a chlorinated hydrocarbon solvent into an aqueous medium to form droplets of the solution, evaporating the chlorinated hydrocarbon solvent in the droplets to form cellulose organic ester spherical particles, and saponifying the cellulose organic ester spherical particles. In the aforesaid process, an acid or alkaki is added and mixed with the cellulose organic ester solution prior to suspending the cellulose organic ester solution into the aqueous medium to control the porosity of the porous, spherical cellulose particles with high reproducibility.

Abstract: Secondary cellulose acetate (cellulose diacetate) of improved whiteness is produced by ripening primary cellulose acetate (cellulose triacetate) using a lower aliphatic alcohol instead of an aqueous medium.

Abstract: A process for preparing porous, spherical cellulose particles which comprises suspending a cellulose organic ester solution dissolved in a chlorinated hydrocarbon solvent into an aqueous medium to form droplets of the solution, evaporating the chlorinated hydrocarbon solvent in the droplets to form cellulose organic ester spherical particles, and saponifying the cellulose organic ester spherical particles. In the aforesaid process, an acid or alkali is added and mixed with the cellulose organic ester solution prior to suspending the cellulose organic ester solution into the aqueous medium to control the porosity of the porous, spherical cellulose particles with high reproducibility.

Abstract: Removal of haze from plastic articles made of cellulose acetate butyrate, such as light polarizing sunglass lenses made of cellulose acetate butyrate and polyvinyl alcohol, is accomplished by immersing said plastic articles in a substantially water-free bath composition at least 70 weight percent of which comprises an active solvent and a carrier solvent, the former being methyl alcohol, ethyl alcohol, propyl alcohol, butyl alcohol, or any mixture thereof, and the latter being ethylene glycol, glycerol, tricresyl phosphate, butyl phthalate, or any mixture thereof. Preferred values of the relative proportions of the active solvent and the carrier solvent are in the range of 90-5 and 10-95 weight percent, respectively, and more preferably, 80-10 and 20-90 weight percent, respectively.

Abstract: Improved method for bleaching cellulose esters, such as cellulose acetate, cellulose acetate propionate and cellulose acetate butyrate, by adding during the hydrolysis reaction of the cellulose ester at from 80.degree. C. to 150.degree. C. a bleaching agent mixture of hydrogen peroxide and at least one monopersulfate salt selected from the group consisting of sodium, potassium and lithium or mixtures thereof.

Abstract: A solution of cellulose triacetate in a mixed solvent consisting essentially of a chlorinated hydrocarbon with a boiling point lower than that of an aqueous medium and an aliphatic higher alcohol with 6 or more than 6 carbon atoms is suspended into the aqueous medium to form droplets of the above-mentioned solution, and then the chlorinated hydrocarbon in the droplets is removed by evaporation to obtain spherical particles of cellulose triacetate containing the aliphatic higher alcohol. The spherical particles thus obtained are saponified and removed of the aliphatic higher alcohol, to prepare porous cellulose spherical particles.

Abstract: Cellulose acetate is prepared acetylating cellulose at a high temperature of 50.degree.-85.degree. C. and then ripening the acetylated cellulose at a high temperature of 110.degree.-120.degree. C.

Abstract: Process for recovering entrained cellulose ester fines from scrubber-coolant water by forming a wet foam containing the fines, floating the wet foam upwardly in a vertically disposed foam flotation column and outwardly along a horizontal straight-line path from which liquid from the wet foam is drained and the fines are introduced in the form of a drier foam into a vessel for subsequent dissolving of the fines, with the horizontal straight-line path being pitched downardly from the horizontal plane.

Abstract: Cellulose diacetate having improved resistance to delustering in hot water is produced by acetylation cellulose in the presence of a catalyst and then hydrolyzing (or ripening) the product to form secondary cellulose acetate; wherein the catalyst in the acetylated mixture is completely neutralized before about the middle of the hydrolysis reaction at the latest and thereafter hydrolysis is carried out at a temperature of about 110.degree. to 120.degree. C. while maintaining the concentration of acetic acid in the reaction mixture at about 67 to 78% by weight based on the total weight of the acetic acid and water, the relation between the hydrolysis temperature and the concentration of acetic acid being defined by the area between and including points A, B, C and D in FIG. 2.

Abstract: Polymers from the group consisting of cellulose and its ester and ether derivatives, of polyvinyl alcohol and its ester derivatives, polymers with vinyl esters and homopolymers and copolymers of acrylates and methacrylates are modified with monofunctional or difunctional cyclic .beta.-ketonic acids or their esters, in particular with succinylsuccinic acid or its ester derivatives. The modified polymers are particularly suitable for obtaining semi-permeable membranes for osmotic separation methods.

Abstract: Biocompatible articles are obtained by treating a polymeric material with a hydrolyzing agent on its surface and covalently binding thereon a biological agent, such as an anti-platelet-aggregation agent.

Abstract: An asymmetrical ultrafiltration membrane based on cellulose hydrate which may be dried without destructive shrinkage and which has been saponified without reduction in flow-through or separation performance is prepared by adding hydrophobic synthetic silicic acid to a casting solution based on cellulose triacetate optionally partially substituted by cellulose diacetate, and then casting the cellulose acetate membrane and saponifying to the cellulose hydrate form.

Abstract: Improved method for preparing cellulose acetate powder, particularly extrusion-grade powder, by direct precipitation, with the precipitation step occurring at a temperature of about 65.degree. C. to about 95.degree. C. and with the coagulating agent subsequently being removed from the resulting liquid powder slurry also at a temperature of about 65.degree. C. to about 95.degree. C.; and the cellulose acetate powder product resulting from the improved method, the powder being particularly adapted to take up plasticizer up to about 50 percent by weight and still flow uniformly without caking or becoming tacky.

Abstract: A compound of the formula, wherein R.sub.1 is hydrogen or a halogen atom, R.sub.2 is ##STR1## R.sub.3 is hydrogen, an alkyl group, a cycloalkyl group or an aralkyl group, and n is an integer of 1 or 2, which is useful as ultraviolet absorber.

Abstract: A novel substance, viz., the salt of .beta.-diethylaminoethyl p-aminobenzoate with celluloseglycolic acid has the following general formula: ##STR1## WHERE X STANDS FOR THE DEGREE OF SUBSTITUTION RANGING FROM 75 TO 100n stands for the degree of polymerization ranging from 30 to 120.A method of producing said compound comprises reacting .beta.-diethylaminoethyl p-aminobenzoate with celluloseglycolic acid in an aqueous medium, whereupon the final product is isolated.The aforementioned compound, viz., the salt of .beta.-diethylaminoethyl p-aminobenzoate with celluloseglycolic acid is the active principle of a local anesthetic drug. The proposed drug finds application in medical practive as an anesthetic in infiltration, conduction or spinal anesthesia, as well as in surface anesthesia.