Abstract: A process for producing a structured, voluminous nonwowen comprises the following steps: (a) a spun nonwoven is produced from a plurality of individual filaments which are stretched and gathered into a skein of fibers; (b) the skein is pressed and not-bonded into a crude nonwoven (12) through a first pair of rollers (9a, b); and (c) the crude nonwoven is further processed through a second pair of rollers (10a, b). The process is characterized in that the individual filaments are initially stretched merely up to a range from 50 to 70% of their maximum possible extension, and in that the crude nonwoven (12) is further processed through a pair of rollers (10a, b) composed of a positive roller (10a) with numerous nops or elevations (11) distributed over the outer surface of the roller and of a negative roller (10) with just as numerous recesses or depressions (12). During rolling, the nops engage the recesses and further stretch the crude non-woven in the area of the roller nops.

Abstract: A process for thermomechanically treating heat bonded thermoplastic and partially thermoplastic nonwoven webs while under low strain rate tension results in significant improvements to the nonwoven web's conformability, softness and impart a high degree of commercially valuable elasticity. The resultant webs find use in all nonwoven applications where softness, conformability and elasticity are useful. The process develops elasticity in only one direction but the two embodiments provide the ability to create elasticity in the machine or cross machine direction of a roll of precursor material. In addition virtually any precursor web containing at least 60% thermally bonded thermoplastic fibers can be used.

Abstract: A process for the manufacture of a rim preform or rim-element having an axis of revolution by the placing on a preforming matrix pre-assembled fibers along two orientations defining deformable meshes. A winding of a strip of fibers is fastened on a circumference of the preforming matrix with asymmetrical orientation of the fibers, whereupon it is applied progressively until covering the entire surface of the preforming matrix by subjecting it to tensions of substantially circumferential orientation.

Abstract: A porous material of a polytetrafluoroethylene (PTFE), which can retain at least 90% of 0.109 .mu.m latex spheres and has a flow rate (IPA flow rate) of at least 0.6 ml/cm.sup.2 /min as measured with isopropyl alcohol under a differential pressure of 1 kg/cm.sup.2. A process for the production of a porous material of PTFE, which comprises, after forming a molded article from fine powder of PTFE by paste extrusion, (1) sintering the molded article, (2) rolling up the molded article thus sintered and heat-treating it at a temperature lower than the melting point of the polytetrafluoroethylene in a state as rolled up, and then (3) stretching the molded article thus heat-treated in at least an uniaxial direction. The porous material of PTFE according to the present invention has micropores and good permeability and particularly is excellent in performance of retaining fine particles.

Abstract: A method for manufacturing a shaped panel from a continuous length of an expanded mat. The method includes transporting an expanded mat on a conveyor. The conveyor includes side chains and a plurality of spaced apart slats, which extend transversely between the side chains, on which the expanded mat is supported. The side chains and the plurality of slats define a plurality of openings in the conveyor. A length of the expanded mat is confined and shaped between a male mold and a female mold by moving the male mold and the female mold into mating relationship through one of the plurality of openings in the conveyor.

Abstract: The invention provides an oriented polyglycolic acid film formed from a thermoplastic resin material which comprises polyglycolic acid having a repeating unit represented by the following formula (1): ##STR1## and the following physical properties: (a) the melt viscosity, .rho.* ?as measured at a temperature of (the melting point, Tm of the polymer+20.degree. C.) and a shear rate of 100/sec! being 500-100,000 Pa.s;(b) the melting point, Tm being at least 150.degree. C.;(c) the melt enthalpy, .DELTA.Hm being at least 20 J/g; and(d) the density being at least 1.50 g/cm.sup.3 as measured in an unoriented, crystallized form, wherein the film has tensile strength of at least 150 MPa, and production processes thereof.

Abstract: Tubular workpieces of oriented polymers such as polyethylene polyester and PVC are formed by drawing a workpiece over an expanding former in the absence of any force perpendicular to the axis of the workpiece. The processes do not require the use of any liquid lubricant. They enable greater degrees of expansion and hence orientation in the direction perpendicular to the axis to be achieved and result in products of improved appearance and strength.

Abstract: A condensed mat of glass fibers incorporating a thermosetting resin is expanded over a mold. Gripping elements at the edges of the mold hold the edges of the expanded mat in place while a second mold confines and deforms the expanded mat between the two molds. Hot air is passed through the porous molds and through the expanded mat to set the thermosetting resin which thereby holds the expanded mat in its deformed shape to form a panel.

Abstract: A method for temperature conditioning a blank of plastic material in which a conditioning mandrel is placed within the blank and thereafter expanded into reliable abutment against the inner surface of the blank. The mandrel is thereafter returned to its initial position. The outer surface of the mandrel is adjusted to and maintained at a certain temperature, whereby, during the abutment, an energy exchange takes place between the blank and the mandrel for adjusting the temperature of the blank. At high temperatures of the mandrel, the mandrel is displaced out of the blank after such short time that the plastic material in the region of the abutment surface never passes the critical temperature of tackiness of the plastic material and/or thermal crystallization of the plastic material. As a rule, the expansion and contraction of the mandrel is repeated one or more times.

Abstract: This invention relates to porous polytetrafluoroethylene (hereinafter PTFE) materials having the property of rapid recovery and a method for producing these materials. The microstructure of the porous PTFE material consists of nodes interconnected by fibrils, substantially all of the fibrils having a bent or wavy appearance. Articles made from these materials are particularly suitable for use in the medical field, but are also useful in other areas such as filtration and fabric applications.

Abstract: A resin film useful mainly for fabricating flexible printed circuits, and a method of producing same. In the process of fabricating a flexible printed circuit board, a copper foil(2) is thermally bonded to a resin film(1), and the copper foil(2) is then etched to a predetermined pattern, in which case the board is generally subject to some dimensional change. In order to minimize such dimensional change it is arranged that the ratio(a/b) of the linear expansion coefficient(a) of the resin film(1) in the direction of mechanical feed(MD direction) to the linear expansion coefficient(b) of the resin film(1) in a direction perpendicular to the MD direction (TD direction) is more than 0.2 but less than 1.0 and that the linear expansion coefficient in MD direction is 0.4-2.0.times. 10.sup.-5 .degree..sup.-1. For such resin film is used a polyimide film containing more than 90% of a recurring unit expressed by a specified general formula. To produce such a resin film, film 1 is drawn by a factor of from 1.0 to 1.

Abstract: A method and apparatus for heat stretching a synthetic fiber rope. The rope is attached to tensioning members and suspended in a liquid medium so that this extends in a generally horizontal direction. The liquid medium has a specific gravity which is approximately equal to that of the rope at the desired stretching temperature, so that the rope is buoyed by this in order to relieve the weight of the segment from the tensioning members. The liquid medium is then heated so that the rope is uniformly heated to the stretching temperature, and tension is applied between the tensioning members so as to stretch the segment of rope to a predetermined increase in length.

Abstract: A process for producing a microporous stretched polyolefin film having a large number of micropores, whereby an unstretched polyolefin film is stretched to predetermined strain amount at a constant stretching temperature by using different strain rates in the initial stage to the final stage. A microporous polyolefin film obtained by the above process can retain a film state even at the melting point or higher temperatures when the film is fixed at the periphery.

Abstract: A polytetrafluoroethylene porous film, which is prepared by stretching a semisintered polytetrafluoroethylene material and heating the stretched material at a temperature higher than the melting point of sintered polytetrafluoroethylene, has an area ratio of fibrils to nodes of from 99:1 to 75:25, an average fibril diameter of from 0.05 to 0.2 .mu.m, a largest node area of not larger than 2 .mu.m.sup.2 and an average pore size of from 0.2 to 0.5 .mu.m and achieves low pressure loss.

Abstract: Hollow profile elements are formed by shaping a starting workpiece that consists of multiple layers of a material having a large width-to-thickness ratio, e.g., woven fabrics or laid materials. The layers are joined by seams to define elongated pockets or channels. Shaping tools are inserted into these channels to form the profile elements with a desired cross sectional shape, which can be constant or varied. The shaping tools employ one or more endless belts that extend in closed loops around guide rollers; the belts are driven so that during the shaping process sliding friction is substantially eliminated between the material of the workpiece and the respective shaping tool.

Abstract: A process and apparatus for drawing polyamide yarn in which the yarn having a lubricating finish is drawn while being spirally advanced in frictional contact with the outer surface of a yarn draw assist element. In such process and apparatus, the outer surface of the draw assist element moves at a speed at least 100 times slower than the speed at which the yarn is advanced. From the draw assist element, the yarn directly advances to a roll initial contact location on a pair of space-apart heated rolls and spirally advances on the rolls through at least one wrap in contact with the outwardly-facing surfaces of the heated rolls. The distance that the yarn spirally advances longitudinally in the wrap can be said to define the wrap advance on the rolls. The roll initial contact location of the heated rolls is oscillated by moving the outer surface of the draw assist element in relation to the pair of heated rolls to oscillate the wrap on the rolls a distance which is at least equal to the wrap advance.

Abstract: A method for temperature conditioning a blank of plastic material in which a conditioning mandrel is placed within the blank and thereafter expanded into reliable abutment against the inner surface of the blank. The mandrel is thereafter returned to its initial position. The outer surface of the mandrel is adjusted to and maintained at a certain temperature, whereby, during the abutment, an energy exchange takes place between the blank and the mandrel for adjusting the temperature of the blank. At high temperatures of the mandrel, the mandrel is displaced out of the blank after such short time that the plastic material in the region of the abutment surface never passes the critical temperature of tackiness of the plastic material and/or thermal crystallization of the plastic material. As a rule, the expansion and contraction of the mandrel is repeated one or more times.

Abstract: A highly orientated, liquid crystalline polymer having a light controlling function and suitable for use in the optoelectronic field is prepared by applying a solution of a polymer which exhibits a thermotropic liquid crystallinity onto a stretched polymer film, drying the applied solution, and thereafter heat-treating the thus-coated film at a temperature at which said liquid crystalline polymer exhibits a liquid crystal phase, for a time sufficient for the molecules of the liquid crystalline polymer to be orientated.

Abstract: A method for forming an inflatable catheter balloon from an initial length of tubing includes longitudinally stretching a first end segment of the tubing element and longitudinally stretching a second end segment of the tubing element. The longitudinally stretched tubing is then heated, blow-molded to radially stretch it and define a desired inflatable portion for the balloon, and cooled.

Abstract: Processes for producing mono- and biaxially drawn polyketone films from linear polymers of carbon monoxide, ethylene, and at least one ethylenically unsaturated hydrocarbon having a melting point of at least 214.degree. C., including drawing of a linear polymer sheet along one or two axes, respectively, at a draw temperature of from about 4.degree. to 15.degree. C. below the melting point of the terpolymer, and at a draw ratio of between 4 to 20. Also disclosed are the products which have and exhibit good properties of strength and stiffness, even at low draw ratios, produced by these processes.

Abstract: A process for biaxially orienting amorphous polymers such as polymethyl methacrylate. The process includes steps of biaxially orienting a feedstock material in a deformation zone; reducing temperature of the material in a cooling zone; and annealing the material in an annealing zone. The process and apparatus produce a biaxially oriented material having enhanced optical quality and impact strength.

Abstract: This invention relates to porous polytetrafluoroethylene (hereinafter PTFE) materials having the property of rapid recovery and a method for producing these materials. The microstructure of the porous PTFE material consists of nodes interconnected by fibrils, substantially all of the fibrils having a bent or wavy appearance. Artricles made from these materials are particularly suitable for use in the medical field, but are also useful in other areas such as filtration and fabric applications.

Abstract: A breathable film and a process for producing the same are disclosed, the breathable film comprising a resin composition comprising (1) 100 parts by weight of a linear low-density polyethylene resin having a density of from 0.870 to 0.915 g/cm.sup.3 and containing from 15 to 50% by weight of a component which is extractable with xylene at room temperature and which has a weight average molecular chain length of from 1,000 to 9,000 .ANG.; (2) from 50 to 400 parts by weight of a filler; and optionally, (3) from 0.5 to 8 parts by weight of a nonionic surface active agent. The breathable film of the invention not only has excellent film moldability and film stretchability but also shows high breathability, good touch and appearance, and high strength.

Abstract: A process to obtain molecular orientations in perforated plates made of extruded plastic material includes a first heating of the plastic material at an extrusion temperature, the extruding of the plastic material in the form of a perforated plate, a first cooling of said plate, a second heating of the plate at the longitudinal orientation temperature, the longitudinal stretching of the plate, a second cooling of the plate at a temperature approaching room temperature, a third heating of the plate at the longitudinal stabilization temperature, a third cooling of the plate, a fourth heating of the plate at the transverse orientation temperature, the transverse stretching of the plate, a fourth cooling of the plate at the transverse stabilization temperature, and the final cooling of the plate.

Abstract: The invention relates to a method for the continuous stretching of a plastics material film, of the type where the film is run off in engagement with two successive rollers which are driven at different tangential speeds, the second roller having a tangential speed which is greater than that of the first roller. The film is run off in engagement with at least a third roller, arranged downstream of the second roller and driven at a tangential speed which is greater than that of the second roller, and it is possible to select as required those of the three rollers in engagement with the film.

Abstract: A porous film having a good water vapor permeability is obtained with a high productivity by melting a resin composition comprising 100 parts by weight of a polyolefin resin and 50 to 500 parts by weight of barium sulfate having an electric conductivity of 250 .mu.S/cm or less in terms of the electric conductivity of a supernatant formed when the barium sulfate is added to water, and a particle size of 0.1 to 7 .mu.m, making the melt into a film and stretching the film to 2.5 to 14 times the original area at least in the uniaxial direction.

Abstract: A biaxially drawn laminated films having a good oxygen barrier property, a good mechanical strength and high thickness uniformity are made by a process comprising:a first step of forming a substantially amorphous unoriented laminated film comprising a saponified ethylene/vinyl acetate copolymer having an ethylene content of 25 to 45 mole % and a polyamide, and drawing the film in the longitudinal direction at a deformation rate of at least 10,000%/min and a draw ratio of 2.7 to 3.5 at 45.degree. to 65.degree. C. by using a roll drawing machine;a second step of transferring the film drawn at the first step to the transverse drawing-initiating point of a tenter type transverse drawing machine, expanding the width of the film at an angle of not larger than 6.degree. with respect to the central line of the film at least until the mechanically set ratio of the tenter clip distance to the original distance becomes at least 1.

Abstract: A thermoplastic draw tape having thick and wide end portions with a relatively thin and narrow central portion between them is produced by movable clamps which stretch the tape between stationary clamps to produce the stretched, oriented portions of the tape. A plurality of movable clamps and a plurality of stationary clamps produce a plurality of stretched central portions so that the stretching time can be greater than the cycle time of bag making machinery with which the stretching apparatus is synchronized.

Abstract: A draw tape for thermoplastic bags is made by feeding tape to a first pair of nip rolls rotating at a relatively slow speed and a second pair rotating at a fast speed. The tape is stretched to form thin and narrow central portions between end portions of unstretched tape. The first nip rolls are increased in speed, or are released to interrupt the stretching. When the rolls are closed, one of them is momentarily retarded or backed up, to produce a rapid transition in the tape between the unstretched end portion and the stretched central portion.

Abstract: A thermoplastic tape having thick and wide end portions with a relatively thin and narrow stretched central portion between them is produced by a first pair of nip rolls running at a slow speed, and a second pair of nip rolls running at a higher speed. The tape between the nip rolls is intermittently moved away from, and toward said first nip rolls to stretch it to produce the relatively thin and narrow central portion. The second pair of nip rolls is mounted on a pivoted arm so that they are movable toward, and away from said first nip rolls. Alternatively, an idler roll between the two pairs is moved toward, and away from, the first nip rolls.

Abstract: Apparatus for making a tubular plastic sheath having one or more imperforate panels around the periphery of the sheath with intervening plastic net connecting the imperforate panels, the apparatus including an extruder, perforating means and stretching means, the improvement being extrusion means to form bands of different thickness asbout the sheath the perforation means being positioned such as to perforate only bands of one thickness.

Abstract: The invention accords to a laminate at least consisting of a first layer from a mixture of at least a propylene polymer and an ethylene-vinylalcohol copolymer and a second layer from at least one propylene polymer, the first layer at least consisting of a mixture of 60-99 parts by weight of a substantially crystalline propylene polymer and 1-40 parts by weight of an ethylene-vinylalcohol copolymer, the second layer at least consisting of a substantially crystalline propylene polymer, the said ethylene-vinylalcohol copolymer having a melting temperature at atmospheric pressure which is at most equal to and not more than 30K lower than the melting temperature at atmospheric pressure of the one of the substantially crystalline propylene polymers used having the highest melting temperature, and the laminate having been subjected to multi-axial stretching to a degree of at least twice in at least 2 directions at a temperature which at most equals the melting temperature of the one of the substantially crystalline

Abstract: Polypropylene fibers having a much improved percentage heat shrinkage and also an improved tenacity are provided, which fibers comprise a polypropylene resin having a density of 0.905 or more, an isotactic pentad ratio of boiling n-heptane-insoluble portion (P.sub.0) of 0.960 or more and a ratio of pentad having two different kinds of configurations (P.sub.2), of 0.002 (0.2%) or less.

Abstract: A friction sheet is described consisting of a single layer or a laminated layer comprising an at least uniaxially oriented high density polyethylene film having a density of at least 0.94 g/cm.sup.3.

Abstract: A destructible marking film having a thickness of about 30 to about 60 microns and a destructibility of not more than 60 kg.cm/mm, said film being composed of a resin composition consisting essentially of (A) 100 parts by weight of a vinyl chloride resin having a degree of polymerization of about 600 to about 2000 and containing 0 to about 5% by weight of a comonomer unit, (B) about 5 to about 20 parts by weight of an alkyl methacrylate resin, (C) about 5 to about 30 parts by weight of a liquid plasticizer, (D) about 10 to about 150 parts by weight of a pigment, and (E) 0 to about 10 parts by weight of at least one additive selected from the group consisting of lubricants and stabilizers. The film can be prepared by shaping the above-defined resin composition by calendering.

Abstract: A greenhouse constructed by stretching over a framework a polyethylene terephthalate film oriented in at least one direction and having a refractive index in the oriented direction of 1.57 to 1.78, a refractive index in the thickness direction of 1.48 to 1.57, a density of 1.340 to 1.390 g/cm.sup.3, and a thickness of 50 to 500 microns, as a material for protecting plants from weather exposure.

Abstract: A stretching machine for plastically straightening an extruded product from an extruding press is disclosed, in which a fixable tail stock and a cylinder operated slidable head stock provide the extruded product with a plastically straightened effect in an automatic operation. Means for variably adjusting the speed of the sliding movement of the head stock and means for automatically changing the sliding direction of the head stock are provided in the stretching machine. The method of operation of the stretching machine includes moving the head stock back toward the tail stock by a small amount after the extruded product has been plastically straightened so that the head stock can be easily disengaged from the extruded product.

Abstract: A diagonal bias-stretching device and a method of enhancing surface grain of imitation-leather material with such device, which device comprises a reciprocating roller moving between lateral positions on either side of a line of advance of an imitation-leather material, to provide for alternating diagonal stretching and relaxing of the material as it moves under tension in the line of advance.

Abstract: Process for enhancement in the mechanical properties of polymeric films prepared from photoconductive polymers, such as poly(N-vinylcarbazole), its homologues and/or its analogues. In this process, polymeric films of these materials are subjected to strain-induced orientation whereby the polymeric chains contained therein are aligned parallel to the lines of force imparted to the film. In order to prevent accompanying deterioration of the charge carrier transport properties of the polymer during such orientation process, the film is subjected to a disordering strain either concurrent with or subsequent to such orientation in order to relax the spatial constraints on their bulky, pendant photoactive groups, and thus relieve them of the distortion imparted during such orientation. Films prepared according to this process have improved flexibility and reduced brittleness, thus making such materials highly suitable for use in flexible electrophotographic imaging members.

Abstract: A multistage stretching process for producing low shrinkage film bands of a thermoplastic polymer, especially polypropylene, wherein the stretching temperature is increased from one stage to the next under prescribed conditions for each stage and the stretched bands are then heat stabilized with shrinkage in a relaxed condition at a temperature of about 20.degree. C. to 30.degree. C. below the crystalline melting point of the polymer. The resulting film bands are especially useful in carpet backings.

Abstract: This invention relates to an improvement in a method for increasing the production of stretched flat film webs of thermoplastic material in which a melt of thermoplastic material is extruded from a slot die, the melt is solidified to form a film, the film is transversely stretched, the stretched film is heat-set, divided into narrower webs, and wound up, the improvement comprising extruding the melt from a slot die wider than the die normally employed for the production of a preliminary film, which usually corresponds to the width of a transverse stretching frame, dividing the melt in the longitudinal direction into at least two films, superposing the film webs, and transversely stretching said superposed webs. The invention also relates to an apparatus for performing the method.

Abstract: A method for drawing and heat-treating an undrawn polyester yarn by drawing the polyester yarn between a heated feed roller and at least one heated draw roller, wherein the surface temperature of the last draw roller is progressively raised from its yarn in-coming side to its yarn out-going side, the yarn is shrunken both on the last draw roller and between the last draw roller and the take-up roller, and the yarn is cooled on the take-up roller. Further, after the method has resumed after being stopped, the running speed of the yarn on the take-up roller is maintained at not more than (100-5.7.times.S)m/min., wherein S is the total shrinkage of the yarn until the yarn heated during the stoppage has been allowed to shrink in the subsequent step. The yarn is then passed over the take-up roller at a running speed of 200 to 1200 m/min.

Abstract: Methods and apparatus are provided for producing seamless or apparently seamless plastic foam cups formed from both seamless and seamed sidewall blanks formed by stretching initially cylindrical blank into frusto-conical shapes and then molding such blanks with either expandable foamed plastic beads or foam plastic discs to form an integral cup bottom with the sidewall in an apparently seamless structure. If cylindrical containers are desired, or if frusto-conical sidewall blanks are utilized no stretching is required. Presizing of sidewall thickness prior to treatment in the mold is also provided.

Abstract: A textile material is molded by preheating to its transition temperature and then rapidly deformed by stretching without cooling. The deformation is maintained for a certain time at the preheating temperature or higher. The material is then quickly cooled. An apparatus for molding particularly fabric has a heat chamber having an opening over which the fabric is fastened, and a molding body having the desired shape and movable towards the heat chamber so as to stretch the fabric while entering partly through the opening. The molding body and heat chamber can be heated and the heat chamber may be evacuated or supplied with air under pressure for cooling the fabric.

Abstract: This invention relates to an improvement in a method for increasing the production of stretched flat film webs of thermoplastic material in which a melt of thermoplastic material is extruded from a slot die, the melt is solidified to form a film, the film is transversely stretched, the stretched film is heat-set, divided into narrower webs, and wound up, the improvement comprising extruding the melt from a slot die wider than the die normally employed for the production of a preliminary film, which usually corresponds to the width of a transverse stretching frame, dividing the melt in the longitudinal direction into at least two films, superposing the film webs, and transversely stretching said superposed webs. The invention also relates to an apparatus for performing the method.

Abstract: Polymeric film is stretched by pulling the film over a first roller which is heated and over a second roller which is cooled, the second roller rotating at a greater peripheral speed than the first roller. The necking-in of the film in the gap between the two rollers is considerably reduced if a heat-transfer liquid is applied betwen marginal portions only of the film and the corresponding peripheral portions of the second, cooled, roller.