Akzona Incorporated

Other

Thomas C Allen

Roland R Loh

Richard B Cass

David B Denning

A filament produced from a wet-spinning process. The process comprising (a) preparing a dispersion of particles of refractory material; (b)preparing a spin mix by mixing said dispersion with a carrier solution comprising a salt of cellulose xanthate, wherein the weight ratio of said particles to cellulose of said cellulose xanthate in said spin mix is greater than about 1:4; (c) wet spinning said spin mix to form at least one filament of cellulose having at least a portion of said particles dispersed therein; and (d) optionally heating said at least one filament to sufficient temperatures and over sufficient durations to remove substantially all of said regenerated cellulose and to sinter said refractory particles to thereby form said at least one filament of refractory material is disclosed for producing fibers of refractory material.

Refractory filaments

A process for producing fibers of refractory material. In one embodiment, a dispersion of particles of refractory material is prepared first. The dispersion then is mixed with a carrier solution of a salt of cellulose xanthate to form a spin mix. Using general wet spinning techniques, a filament of regenerated cellulose is formed from the spin mix. The filament has the particles dispersed therein. At this point, the filament can be utilized as a mixture of cellulose and refractory material, or it can be heat treated. If heated, the filament is raised to sufficient temperatures and over sufficient durations to remove substantially all of the regenerated cellulose and to sinter the particles of refractory material to form a filament.

Method for producing refractory filaments

This container assembly is closed by removable cover and includes a base formed by two transparent nested cup shaped inner and outer members spaced to define a closed thermal insulation chamber therebetween. The inner member has a diametral partition structure dividing this member into two compartments. The cover has two spaced nipples to which may be connected respectively to an aspiration tube and a needle assembly for discharging fluids or a wash from a follicle or another similar site, into the chambers when the cover is rotated to either one of two positions on the base. The cover may be replaced by a transparent, imperforate cover for reviewing the contents of the compartments by a microscope to detect the presence of an oocyte.

Aspiration container assembly for collecting follicular fluids

This surgical trocar assembly has the needle of a stylet removably disposed inside a first cannula which is inside a second cannula in a concentric array. The needle has a sharp point to pierce a body part to be drained of fluids. A first fitting on the first cannula has a first nipple to engage an aspiration tube when the needle is removed. The fitting has a tenon to engage in a tubular member of a Y-shaped joint structure. The tubular member has a lateral second nipple to engage an end of a wash fluid feed tube. A second fitting on the second cannula engages on the tubular member so that wash water passes through the tubular member between the first and second cannulas. The first cannula has a tapered sharp open end to enter the body part for aspirating fluids therefrom. The second cannula has a tapered end to engage the outside of the first cannula near its tapered open end, and further has lateral openings to discharge wash fluid from the second cannula to the body part.

Trocar assembly for drawing fluids from a body part

A method for oven drying chemically modified cellulosic materials, especially fibers, having improved fluid absorbency involves incorporating into the cellulose structure while swollen an amphiphilic compound miscible with water which will not evaporate when the fiber is oven dried and will remain in the fiber to prevent collapse of the fiber as the water is removed. The improved method of drying the fibrous cellulosic material produces a product having saline absorbency about equal to that produced when the fibers are dried with a water-miscible solvent and avoids the use of volatile solvents and the disadvantages inherent therewith. The fibers provided by the invention are especially suitable for use in pads which are to be used for absorbing water and body fluids.

Method for drying absorbent modified cellulosic polymers and the like

A regenerated cellulose fiber containing an alloying polymer of acrylic acid or methacrylic acid, or a copolymer containing acrylic and methacrylic acid moieties or an alkali metal or ammonium salt thereof or other anionic alloying polymers or copolymer is prepared by a process wherein the alloying polymer is mixed with a viscose solution of known unreacted sodium hydroxide concentration, the sodium hydroxide concentration in the resulting mixture is increased to compensate for any loss in concentration due to neutralization and/or dilution effects by the addition of the alloying polymer to the viscose. Increasing the sodium hydroxide concentration greater than that required to restore the concentration to the original level has resulted in dramatic increases in absorbency. The resulting viscose solution is extruded into a spin bath in which the sulfuric acid concentration is reduced so that the resulting fibers will have at least 90% of the crimp of a fiber produced from the viscose solution without alloying polymer or copolymer.

Process for spinning regenerated cellulose fibers containing an alloying

Highly absorbent cellulosic fibers are made by incorporating therein from 2%-35% based on the weight of cellulose of a polymerized acrylamido-2-methylpropane sulfonic acid or a copolymer of acrylamido-2-methylpropane sulfonic acid with any one or combination of other polymerizable hydrophilic monomers such as acrylic acid, methacrylic acid, acrylonitrile and the like.

Highly absorbent fibers of rayon with sulfonic acid polymer incorporated

Cardable cellulosic fibers having improved water and fluid absorbency are made by incorporating therein an alkali metal or ammonium salt of a copolymer of acrylic acid and methacrylic acid prepared by a process wherein the two monomers are mixed together in ratios during the polymerization so that the amount of copolymer chains substantially richer in methacrylic acid moieties than the total ratio of acrylic acid and methacrylic acid monomers included in the copolymerization process and the number of copolymer chains considerably lower in degree of polymerization than the copolymer average are minimized.

Alloy fibers of rayon and an alkali metal or ammonium salt of an

Highly absorbent, cardable cellulosic fibers are made by incorporating therein, an alkali metal or ammonium salt of a copolymer of acrylic acid and methacrylic acid, where the ratio of acrylic acid units to methacrylic acid units (by weight) is from 90:10 to 10:90.

Growing community of inventors

Asheville, NC, United States of America

Thomas C Allen