Abstract: Reinforcing fibers of plastic having a surface tension of from 40 dyn/cm to about the surface tension of water are disclosed. The fibers can be easily and uniformly disposed in matrices. For organic matrices, a surface tension of 40-50 dyn/cm is effective. For cement matrices, a surface tension about 70-75 dyn/cm is effective. The high surface tensions are obtained by a corona treatment and subsequent application of a hydrophilic avivage. Corona treatment may be performed on the fibers, or on films from which the fibers are made.

Abstract: The invention provides a novel means for the improvement of the surface properties of a gramophone record made of a vinyl chloride-based resin which is deficient in respect of the susceptibility to electrostatic charging and anti-wearing resistance with consequent noise generation in the playing of the record. The inventive method comprises irradiating the surface of the gramophone record with ultraviolet light having a substantial energy distribution in the wavelength region of 200 nm or shorter in an atmosphere of oxygen or an oxygen-containing gaseous mixture of which the pressure or partial pressure of oxygen is at least 15 Torr. The effect of the ultraviolet irradiation is further enhanced and the durability of the antistatic effect is increased by bringing the ultraviolet-irradiated surface of the gramophone record into contact with a solution containing a surface active agent followed by washing with water and drying.

Abstract: In order to form in a concrete body during casting thereof a part-spherical recess around the head of a pickup bolt having a stem embedded in the body, an apparatus is employed comprising a pair of like elements each having an outer surface complementary to a respective half of the inner surface of the recess. These elements are formed with respective halves of a seat that complementarily surrounds the bolt head and the stem in the recess. A bridge is provided with a pair of pivots that define pivot axes for the respective elements, and a manipulating member is rigidly connected to this bridge.

Abstract: A novel system for producing film by extruding and/or casting at least two layers of resin, such as polyacrylonitrile homopolymer or interpolymers. The system provides for co-extruding a continuous multi-layer film with contiguous or tandem dies from a first supply of homogeneous resin solution and a second supply of non-homogeneous redissolved resin scrap. The film may be cast onto a smooth cooled drum surface to form substantially continuous adjacent layers from two or more resin supplies. By stripping the film from the drum as a continuous film strip and stretching the film an oriented structure is provided. Scrap resin, such as selvage trimmed from the stretched film or mill scrap, is comminuted and redissolved in solvent for recycle to the second supply of the extrusion step. The homogeneous layer prevents film disruption by inhomogeneities present in the contiguous layer containing redissolved scrap, which might cause localized stresses in the film and discontinuities during stretching.

Abstract: A conductive video disc replica is cleaned by washing with an aqueous solution comprising an oxidizing agent, a base and a surfactant of a fluorocarbon added in an amount so that the solution has a surface energy of about 35 dynes/cm.sup.2 or less. This solution removes metallic and oxygen-containing impurities from the surface of the disc and leaves a fluorinated surface.

Abstract: An improved process for the production of rubber hydrochloride sheet is described in which a rubber sheet is advanced through a reaction zone essentially in one direction while totally immersed in a solution of hydrogen chloride in an organic solvent capable of swelling the rubber, flotation of the rubber sheet in the reaction solution being prevented, and the slack in the sheet caused by the initial swelling thereof being taken up to keep the sheet in substantially fully extended form to prevent it from contacting itself while in tacky condition, washing the sheet with an organic solvent or mixture thereof capable of removing the entrained, unreacted hydrogen chloride and other contaminants, drying the sheet in air at about 60.degree. C. to 80.degree. C., and calendering the still warm sheet to a finished rubber hydrochloride sheet of uniform thickness; the preferred solvent for both the hydrochlorination and washing operations being ethyl acetate.

Abstract: In the manufacture of wound hollow fiber dialysis cartridges, rigid preliminary tube sheets are formed near each end of the winding, outwardly of the area of the winding which will ultimately be used in finished cartridges. The preliminary tube sheets are then cut transversely to the winding mandrel to expose the hollow fiber ends. The cut preliminary tube sheets, mandrel, and fibers now form a unitary structure which can be washed and treated to make the fiber surface easily adherable to the potting material from which the permanent tube sheets are thereafter formed. After forming the permanent tube sheet, the winding is cut into individual cartridges, and the preliminary tube sheets are discarded.

Abstract: A method of clearing a polysaccharide ester membrane employing a clearing solvent comprising a first moiety selected from a group consisting of alcohols, ketones, ethers, esters, and mixtures thereof and a second moiety comprising a solvent selected from a group consisting of 2-ethoxyethanol, 2-ethoxyethyl acetate, methyl acetoacetate, ethyl acetoacetate, acetol, and mixtures thereof, the first moiety having a boiling point lower than the second moiety.The solvents employed as the second moiety of the instant invention's clearing solvent are much less toxic than solvents employed as the second moiety of prior art clearing solvents.

Abstract: The invention relates to a process for the production of hydrophilic filaments and fibers from filament-forming synthetic polymers by spinning a solution which, in addition to a suitable solvent, contains from 5 to 50% by weight, based on the solvent and solids, of a substance which is essentially a non-solvent for the polymer, has a higher boiling point than the solvent used and is readily miscible with the spinning solvent and with a liquid suitable as a washing liquid for the filaments, and subsequently washing this substance out of the filaments, wherein a suspension is initially prepared at room temperature from the solvent, the polymer and the substance, the suspension thus prepared is subsequently heated, left for at least one minute and at most 15 minutes at a temperature of at least 30.degree. C. and of at most 60.degree. C.

Abstract: An exposed aggregate finishing method for concrete. The method comprises coating the inside faces of a form for concrete with a cement setting retarder, drying, coating the dried faces with a synthetic organic polymer coating material which is soluble in an aqueous alkaline solution of cement, but is insoluble in water; and drying the coated faces. Alternatively, the method may be carried out by coating the inside faces of the form for concrete with the mixture of the cement setting retarder and the organic polymer coating material and drying the coated faces. Concrete is thereafter placed in the concrete form, the form removed and the surface of the molded concrete washed to make the surface rough.

Abstract: Method and apparatus for producing a concrete panel having a fractured rib finish is disclosed. A quantity of relatively low slump concrete mixture is cast upon a pallet in the form of a panel and is extruded to define projecting ribs and channels. The casting is permitted to harden until the concrete becomes rigid but not completely set. Thereafter an array of wedges secured to a carriage assembly is drawn along the length of the panel with each wedge disposed in shearing engagement with edge portions of an adjacent pair of ribs. Each wedge includes a shoulder portion wider than the channel for shearing and forcibly displacing portions of the ribs as the wedge is drawn through the channel. Means are provided for propelling the carriage assembly along the length of the panel and in a direction parallel to the orientation of the ribs. A concrete panel having a fractured rib finish produced by the method of the invention is similar in appearance to a concrete panel having a manually hammered rib finish.

Abstract: A composition comprising .alpha.-alumina in a concentration of at least 99.95 weight percent and process for producing such .alpha.-alumina wherein alumina having an alkali metal content between 0.05 and 0.60 weight percent and Al.sub.2 O.sub.3 content of more than 95 weight percent is electrically fused with silica and additional alkali, if desired, in an electric arc furnace, the heated composition is cooled, comminuted and the so-formed glass phase is removed from an alumina containing phase by mechanical or chemical means.

Abstract: A method of producing a curved sausage casing by treating a sausage casing before curving with caustic solution and neutralizing the casing while in the curved configuration.

Abstract: The invention relates to a method of manufacturing shaped articles from crystalline or quasi-crystalline acrylonitrile polymers and copolymers, said method consisting in cooling down a solution of said polymer or copolymer in a mixture containing from 50 to 99.5% by weight of a solvent and from 0.5 to 50% by weight of a precipitant to a temperature below the gelation point of the solution until the same gelatinizes, without changing its composition, to the desired shape, whereafter the solvent is removed from the shaped thermoreversible gel thus obtained at temperatures lower than the gelation point of the solution, preferably using a liquid precipitant of polyacrylonitrile miscible with the solvent. It is advantageous to remove the solvent at a temperature which is at least 10.degree. C. lower than the gelation temperature of the polymer solution used. The shaping can be carried out in any convenient way, e.g. using a stationary or rotating mold.

Abstract: Method and apparatus are provided for treating one surface of a wall of articles to be used in contact with blood. A solution which is compatible with blood is brought into contact with the surface and a partial vacuum is applied to the wall for a predetermined time period. This partial vacuum causes gas nuclei trapped in irregularities in the surface to permeate through the wall. Consequently when blood displaces the solution there is less likelihood of blood platelets being trapped on the surface with eventual blood clotting.

Abstract: An acrylonitrile polymer film is produced by the steps of:Extruding an acrylonitrile polymer solution in a tubular shape into a coagulation liquid bath while a coagulation liquid is introduced into and withdrawn from the inside of the extruded tubular-shaped film;Removing the solvent remaining in the coagulated tubular film, and;Biaxially stretching the tubular film containing 5 to 23% by weight of water based on the dry weight, at a temperature of 100.degree.-170.degree. C. at least twice its original length both in the longitudinal and transverse directions by a tubular stretching procedure.

Abstract: The invention relates to a process for continuously removing residual solvent from filaments of dry-spun acrylonitrile polymers to values of below 2% by weight of solvent by a multi-stage hot-wash with low quantities of water.

Abstract: Fibers of arylene oxadiazole/arylene N-alkylhydrazide copolymer and of high tensile strength are prepared by a unique solution spinning process, whereby an arylene oxadiazole/arylene N-alkyloxadiazolium hydrosulfate copolymer in sulfuric acid or oleum is extruded into an aqueous coagulation medium in which concurrently a fiber is formed and the latter-mentioned copolymer undergoes a chemical transformation to provide the first-mentioned copolymer.

Abstract: A method of restoring the fluid permeability of the surface of the mold face of a used, ceramic, fluid-release mold body which has become fouled with accumulated silicate material from the plastic clay composition formed by the mold, comprising treating the fouled surface with a fluorine containing acid such as fluosilicic acid, or hydrofluoric acid.

Abstract: An improved process for releasably enclosing a solution of a micelle-forming surfactant in a receptacle comprising a microporous cellulose membrane is provided.

Abstract: A method of forming walls for pools, waterfalls and the like having surfaces accurately simulating material surfaces, such as rock surfaces. The method is comprised of the steps of coating a rock surface to be simulated with latex, coating the latex with urethane resin, and allowing the resin to foam in place. The urethane foam-latex member is then removed from the rock to be simulated and is used as one wall of the pouring form for forming the corresponding wall of the pool, etc. In the case of swimming pools, a trench in the position of the desired walls of a pool can be dug with the inner surfaces of the trench provided with the foam-latex panels for forming the simulated rock surface on the resulting pool walls. Alternate embodiments and methods of practicing the invention are disclosed.

Abstract: An aromatic polyamide film having a dielectric strength of at least about 150 kv/mm which is useful as an electric insulating material. This film is obtained by casting a solution comprising poly(m-phenylene isophthalamide) or a copolymer thereof and an amide type solvent, drying the cast product to form a film having a residual solvent content of not more than about 60% by weight, immersing the film in an aqueous medium kept at not more than about 20.degree. C, and stretching the resulting wet film containing at least about 5% by weight of the aqueous medium in at least one direction to at least about 1.4 times the original dimension.

Abstract: Method of preparing films of acrylonitrile polymer exhibiting very high tensile strength, stiffness, optical clarity, and outstanding gas barrier properties. Method entails extruding a hot, concentrated solution of said polymer in a solvent therefor that is water-soluble, e.g., dimethyl sulfoxide, onto a film-supporting surface, e.g., a flat surface, or a drum, which, preferably, has a low energy surface such as provided by wetting the surface with aqueous dimethyl sulfoxide, or coated with polytetrafluoroethylene, or other suitable means to thereby form a film. The resulting film is then contacted with an aqueous medium, e.g., water to remove the solvent (e.g., dimethyl sulfoxide) and partially replace it with water, this treatment being effected under conditions that will prevent the film from curling or puckering. The resulting film is composed essentially of acrylonitrile polymer and water, and is ignition resistant.

Abstract: New solvents for chitin comprising dimethylacetamide, N-methylpyrrolidone or mixtures of these in combination with a minor proportion of lithium chloride, and their use in the purification of chitin for regeneration in the form of films and fibers are described.

Abstract: A process for metal plating shaped articles, such as cast or molded articles of synthetic resins, includes the steps of (a) diffusing or scattering numerous fine metal particles (or pieces) over the surface and outermost layer of the articles, (b) etching exposed surfaces of the metal particles, (c) performing thereafter metal plating, (d) and thereby solidly combining or joining the plating layer and the articles through the medium of the fine metal particles, whereby the resulting plated articles are extremely eminent in abrasion and shock resistance which is essentially useful for casting and molding patterns or core boxes.

Abstract: A process and apparatus is described by means of which the pollution of the surrounding atmosphere by the fumes of isocyanate, liberated during the continuous formation of isocyanate-based polymer foam bunstock, is minimized. The bunstock, after the foam rise and gelation is completed, is passed through a zone, installed on the bunstock conveyor, in which the foam is subjected to the action of a fine mist of water sprayed on to the top and sides of the foam bunstock. The application of water in this manner does not affect the properties or appearance of the foam and any excess water coating the surface of the foam evaporates during the remainder of the passage of the bunstock down the conveyor. The above procedure is particularly applicable to the production of foam bunstock which is based on the highly volatile toluene diisocyanate.

Abstract: An improved neutralization process for use in the high speed spinning of an inorganic acid-containing polyamide spin dope.

Abstract: A continuous process for producing viscose yarn including feeding a viscose solution through spinneret dies into a spinning bath to spin viscose yarn, and finally regenerating and concurrently cooling the spun yarn, now carrying entrapped carbon bisulfide in the form of an emulsion, from said spinning bath at a temperature below the boiling point of the carbon bisulfide. Thereafter, while maintaining the finally regenerated yarn in a cooled condition, washing the yarn with water whereby some water, in addition to the carbon bisulfide, becomes entrapped in the yarn, subjecting the washed yarn to avivage treatment, and finally drying the resulting yarn at an elevated temperature sufficient to concurrently remove both the entrapped water and the carbon bisulfide from the yarn. Thereafter, the resulting dried and carbon bisulfide-free yarn is wound into a package.

Abstract: A method is disclosed which involves the production of shaped silicone elastomer-containing articles. In making an article of this type, a silicone elastomer-containing mass is formed to the desired configuration by subjecting it to pressure with a suitable die or pair of dies. Generally, the shaped mass will adhere to the die, or to one of the pair of dies, used for the shaping operation. A mechanical loosening of the shaped mass poses great difficulties. On the one hand, if sufficient caution is not excerised during loosening of the shaped mass, scratching or breakage of the latter will occur, particularly if the shaped mass is of small thickness. On the other hand, the exercise of great caution during loosening of the shaped mass is very time-consuming and, further, may still not yield satisfactory results if the shaped mass is of small thicnkess.

Abstract: A load-bearing wall panel is fabricated by disposing an assembly of spaced-apart and aligned, hollow-cored bricks onto a molding base containing melted paraffin. Contact of the cooler bricks with the melted paraffin forms a thin skin of solidified paraffin on the brick bottom portions and forces melted paraffin within the joints forming therein a double-convex configuration of solidified paraffin, thereby water-proof sealing the brick bottom portions and joints preparatory to mortar introduction. After curing of the mortar introduced in the joints and cores, the resulting wall panel has load-bearing capacity and unique, double-concave mortar joints that are smooth, water-proof and weather-proof.

Abstract: Windshield wiper blades which have been previously treated with a halogen are subjected to treatment with a solution selected from the group of those having a pH above about 12 and those having a pH between 7 and 12 and a cation concentration of at least -0.09 pH + 1.13 moles per liter where pH is the pH of the solution whereby improved wipe and wear properties are obtained.

Abstract: Colloidally dispersible microcrystalline polyesters are prepared by a hydrolytic removal of amorphous regions in synthetic, linear polyesters followed by a mechanical disintegration of the resulting aggregated microcrystals to produce discrete microcrystalline particles at least 5% by weight having a particle size not exceeding 1 micron. The microcrystalline polyesters exhibit a sharp X-ray diffraction pattern and distinctly modified thermal behavior as compared to the parent or precursor polyester resin.

Abstract: In molding polyurethane integral-skin foam the foam tends to stick to the mold surface. Conventional mold release agents have not been found effective; they fail to provide full release of the molded product, are not durable enough to withstand more than one molding cycle, interfere with development of the integral skin, or plate onto the integral-skin thus necessitating solvent washing of the molded foam product. This invention is a method of preparing a mold to release flexible polyurethane integral-skin foam, free from skin damage and other defects, that is durable, i.e., that will permit many molding cycles before requiring replacement, and that permits the molded foam to be merely water washed to remove all traces of the mold release agent.