Abstract: An inorganic fiber catalyst includes an alumina-silica fiber base material, and a plurality of catalyst component particles contained in the alumina-silica fiber base material. A mean particle diameter of the catalyst component particles contained in at least a surface portion of the alumina-silica fiber base material is 50 nm or less, and a standard deviation of particle diameters of the catalyst component particles is 30 or less.

Abstract: The invention is a demineralization apparatus comprising an anode chamber disposed at one end of a vessel having an anode at the inside of the anode chamber. A cathode chamber is disposed at the other end of the vessel, having a cathode at the inside of the cathode chamber. At lease one diluting chamber and at least one concentrating chamber are located alternately between the anode chamber and the cathode chamber. The diluting chamber has an anion exchange membrane on the anode chamber side and a cation exchange membrane on the cathode chamber side. The diluting chamber has an inlet for water to be treated and an outlet for demineralized water. The concentrating chamber has an inlet for water and an outlet for ion-concentrated water. The diluting chamber contains a cloth comprising a mixture of strongly acidic cation exchange fibers, strongly basic anion exchange fibers and ionically inactive synthetic fibers. Preferably, the mixture contains from 20 to 70% by weight ionically inactive synthetic fibers.

Abstract: A thread-reinforced paper sheet comprises upper and lower paper layers and a reinforcing thread interposed therebetween. A thread-reinforced gummed tape comprises a tape base material which consists of upper and lower paper layers and a reinforcing thread interposed between the upper and lower paper layers, and a moisture activated adhesive layer formed on one of surfaces of the tape base material. In each of the thread-reinforced paper sheet and the thread-reinforced gummed tape, a water-soluble or water-dispersible adhesive is used to laminate the upper and lower paper layers, and a water-soluble thread is used as the reinforcing thread. Each of such thread-reinforced paper sheet and such thread-reinforced gummed tape exhibits a strength equivalent to that of the prior art article and moreover, has a complete disintegratability. Thus, a regeneratable thread-reinforced paper sheet as well as a regeneratable thread-reinforced gummed tape is provided.

Abstract: A process for the production of continuous inorganic fibers is disclosed which comprises causing a spinning dope composed of a water-soluble organic polymer, a water-soluble inorganic salt capable of forming a refractory inorganic oxide, additives, and water and adjusted to a viscosity of 200 to 2000 poises at 20.degree. C. to be dry spun by the use of a spinning nozzle containing a plurality of spinnerets each provided on the spinning dope outlet side of a nozzle plate with a protuberance having a wall thickness of not more than 0.5 mm at the tip thereof and subjecting the spun threads of the spinning dope to a thermal treatment. An apparatus for working the process is also disclosed which is provided with a spinning nozzle having a plurality of spinnerets bored through a nozzle plate and severally through protuberances formed on the spinning dope outlet side of the nozzle plate in such a manner that the walls of the protuberances surrounding the spinnerets have a thickness of not more than 0.

Abstract: Rare earth metals are adsorbed on an ion exchange fiber comprising an ion exchanger having a strong cation exchange group and a weak cation exchange group, and the adsorbed metals are fractionally eluted with an aqueous solution of a chelating agent, whereby the respective rare earth metals can be separated at high efficiency in a short time. According to this method, elution can be accomplished at an elution rate of 5.0 or above in terms of space velocity.

Abstract: A novel enzyme-active fibrous material is proposed comprising fibers of a rtially aminoacetalized polyvinyl alcohol as the support and an enzyme adsorbed and bonded thereto such as glucose isomerase, invertase, urease and the like. The enzyme-active fibrous material of the invention is readily prepared by dipping fibers of the partially aminoacetalized polyvinyl alcohol in an aqueous solution of the desired enzyme. The enzymatic activity and the physical properties of the fibers are remarkably improved by the use of extra-fine fibers prepared with composite fibers of a partially aminoacetalized polyvinyl alcohol and a polyethyleneoxide subjected to selective leaching away of the latter component or by the use of so-called sheath-and-core type or side-by-side type composite fibers of which one of the components is a partially aminoacetalized polyvinyl alcohol.

Abstract: Superfine fibers of polyvinyl alcohol type having a single fiber diameter of 0.1-1.0.mu. and a fineness of 0.8-80.times.10.sup.-4 d/f are baked in the presence of a dehydration catalyst so that the weight loss ratio of fibers falls under the range of about 5 to 40%.When ion-exchange radicals are introduced into the partially dehydrated fiber, superfine fibers with a high ion-exchange rate are obtained.

Abstract: A partially polyenized polyvinyl alcohol fiber is obtained by heating and dehydration polyvinyl alcohol type fibers at temperatures of about 80.degree. to 350.degree. C so that the dehydration weight loss falls within the range of about 5% to 40%. An ion-exchange radical is introduced into the partially polyenized polyvinyl alcohol fiber to obtain fibers with an ion-exchange capacity. The ion-exchange fiber thus obtained exhibits an exchange capacity comparable to ion-exchange resins and has practical properties as fibers, such as good chemical resistance and flexibility.