Abstract: A solvent spun bamboo fiber with a high wet modulus and a producing method thereof are disclosed. The producing method includes: activating by adding a bamboo pulp into de-ionized water, adjusting the pH value, adding cellulase and adjusting the pH value by adding alkali; squeezing by vacuum dehydration; pre-dissolving by adding an aqueous solution containing 50-88% by mass of N-methylmorpholine-N-oxide; then dissolving by putting the above pre-dissolved mixture into a dissolver, heating, vacuumizing, dehydrating, dissolving, homogenizing and defoaming; spinning by spraying through a spinneret and forming a bamboo fiber by dry-wet spinning; water washing; bleaching; oiling; and drying. The present method is simple to operate, free of industrial pollution, low energy consuming, and highly safe. The bamboo fiber produced by the present method not only keeps the natural physical and chemical properties of bamboo fiber, but also has a high wet modulus without harmful chemical residues.

Abstract: The present invention provides yarn and cloths made by utilizing bamboo fiber and methods for manufacturing these yarn and cloths, thereby the bamboo fiber can be utilized by being extracted from sheaths of bamboo shoots or bamboo sheaths that generate at the root of bamboo abundantly, which have been left as they are or mostly disposed of as wastes. By fibrillating or chemically treating bamboo sheaths 10 which is a main raw material, bamboo fiber 16 mainly comprising cellulose is obtained, and then it is formed into yarn by spinning. A cloth is produced as woven or knitted fabric using the yarn.

Abstract: A hollow fiber blood purifying membrane which is a hollow fiber membrane substantially composed of cellulose acetate, has a substantially non-oriented distribution of cellulose acetate polymer particles on the inner surface of the hollow fibers, has a dense layer with a thickness in the range of 30-1000 nm on both the inner and outer surface of the hollow fibers and a porous structure which is substantially uniform at the membrane wall between the two dense layers, and has an in vitro ultrafiltration rate (UFR) of 10 to 50 ml/m.sup.2 .multidot.mmHg.multidot.hr and a (in vivo UFR)/(in vitro UFR) ratio of at least 0.3, a blood plasma albumin permeation blockage of at least 90%, and an in vivo .beta..sub.2 -microglobulin (.beta..sub.2 -MG) sieving coefficient of at least 0.4, as well as a process for its production.

Abstract: A dialysis membrane is made of a regenerated cellulose polymer in the form of a hollow fiber with a continuous internal cavity filled essentially with a gas. The hollow fiber has a porous inner and an outer surface. The outer surface of the hollow fiber is formed by a thin skin which has fine lengthwise grooves. The inner surface of the hollow fiber is positively modified by physical and/or chemical means.The invention also includes a method for manufacturing such a dialysis membrane.

Abstract: A dialysis membrane for hemodialysis in the form of sheet films, tubular films, or hollow fibers is composed of a polysaccharide ether. The polysaccharide ether has a structure given by the formula ##STR1## in which cell is the skeleton of the unmodified cellulose molecule or of the chitin molecule, each with no hydroxyl groups, s is equal to 3 for the unmodified cellulose molecule and 2 for the chitin molecule, and x is the degree of etherification, which is in the range from 0.001 to 0.079, and R is an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, arylalkyl, arylalkenyl, and/or arylalkynyl group with 3 to 25 carbon atoms, and/or the radical of a heterocyclic compound with 3 to 25 carbon atoms, in which the carbon chain may be interrupted by oxygen or sulfur atoms.

Abstract: A dialysis membrane in the form of a hollow fiber with a continuous internal cavity is made of cellulose acetate or a cellulose acetate derivative. The hollow fiber is made by using a gas to form the internal hollow cavity. A dialysis membrane in the form of a hollow fiber with a continuous hollow cavity may be made in a process using a spinning solution containing an organic carboxylic acid. Modification agents can be added to the solution and the solution extruded through a spinneret suitable for manufacturing hollow fibers, while an internal medium is introduced simultaneously into the internal cavity of the forming hollow fiber. The precipitation of the dialysis membrane thus formed and an ordinary further aftertreatment take place subsequently in a precipitation bath. The hollow fiber is made by using a gas as the internal medium to form the internal cavity.

Abstract: A material is formed into hollow fiber form, and the surface characteristics of the interior bore is selectively modified in a predetermined fashion by a reactive lumen fluid. Nucleophilic materials, such as regenerated cellulose, can be formed into hollow fibers and simultaneously modified to improve their biocompatibility in accordance with the invention.

Abstract: Unstretched hollow fibers of cuprammonium cellulose for dialysis possessing a film structure having a porosity of 15 to 25%, a pore diameter of 25 to 40 .ANG., and an ultrafiltration ratio of 3.0 to 5.5 ml/mmHg.hr.m.sup.2 are obtained by extruding, coagulating, and regenerating a cuprammonium cellulose spinning dope having a cellulose concentration of 6.8 to 8.7% and a viscosity of 500 to 1,300 poises (at 20.degree. C.).

Abstract: A porous regenerated cellulose hollow fiber is obtained by a micro-phase-separation method. The hollow fiber is characterized in that the viscosity average molecular weight is at least 5.times.10.sup.4, each of the average pore diameter D.sub.1 on the inner wall surface of the hollow fiber and the average pore diameter D.sub.2 on the outer wall surface is 0.02 to 10 .mu.m, the in-plane porosity Pr on the outer wall surface is at least 10%, and the hollow fiber comprises a wall thickness portion having pores piercing therethrough between the inner wall surface and outer wall surface and a hollow portion extending continuously over the entire fiber length.

Abstract: A hollow fiber of cuprammonium regenerated cellulose having an axially disposed cylindrical bore extending throughout the fiber length, said bore being filled with a gas. The hollow fiber exhibits an improved dialysis performance and ultrafiltration rate over the conventional hollow fiber. Such a hollow fiber can be produced by a process comprising (a) extruding a spinning dope through an annular orifice while simultaneously injecting a gas into the bore as it is formed, and (b) allowing the fiber extrudate to free fall in an air space and dive into a depth of from 2 to 20 mm below the surface of a coagulation bath only with a downward force gained during said free fall.

Abstract: A method for the manufacture of a hollow fiber which comprises extruding a cellulosic spinning dope through an annular spinning nozzle directly into a non-coagulative liquid layer in a bath filled in the upper layer with a coagulative liquid relative to said spinning dope and in the lower layer with a non-coagulative liquid of a halogenated hydrocarbon and, at the same time, introducing a non-coagulative liquid relative to said spinning dope into the inner center of the tubularly extruded thread of spinning dope, and subsequently passing the resultant tubular fiber of spinning dope through said coagulative liquid thereby coagulating and regenerating the fiber.

Abstract: A liquid composition for the manufacture of a membrane, comprising a reaction product a cuprammonium cellulose with an ammonium or alkali metal salt of a polymer containing 10 to 70 equivalent percent of a carboxyl group and having a number-averaged molecular weight in the range of from 500 to 200,000, and a membrane is obtained by molding the composition in the form of a film, immersing the shaped article thus obtained in a dilute sulfuric acid solution thereby coagulating and regenerating it, subsequently immersing the shaped article in an strong alkali solution thereby expelling said ammonium or alkali metal salt of the polymer therefrom and forming therein fine pores substantially corresponding to the molecular weight of said salt.

Abstract: Dialysis membranes are described in which two or more hollow fibers of cellulose regenerated from cuoxam solution are spun together and connected to each other parallel to the fiber axis. The connection may be in the form of crosspieces, which should be between about 1 and 3 times the thickness of the hollow fiber walls. A novel process for preparation of the dialysis membrane hollow fibers is also disclosed.

Abstract: A dialyzing membrane, especially for hemodialysis, formed as a hollow fiber, tubular foil or flat sheet by regeneration of cellulose from a cuprammonium solution, the membrane comprising at least two firmly adhered cellulosic layers including at least one dialyzing layer consisting essentially of a semipermeable regenerated cellulose and at least one adsorbent layer consisting of said regenerated cellulose containing embedded therein fine particles of an adsorbent material in an amount of up to 95% by weight with reference to the dry weight of the adsorbent layer, preferably 1 to 90% and especially 20 to 70% by weight, when the adsorbent layer is part of a hollow fiber structure.

Abstract: An improved dialyzing hollow fiber of cuprammonium regenerated cellulose, showing a substantially similar network structure of fine gap passage routes having a max. gap size of 200 A when .[.seen.]. .Iadd.observed .Iaddend.at .[.its.]. any cross-section and .[.logitudinal.]. .Iadd.longitudinal .Iaddend.section, having skinless structure at its inside and outside surface of the hollow fiber and representing a superior water permeability.