Abstract: A ceramic composite is provided comprising ceramic fibers, glass microballoons and/or diatoms, bound together with a ceramic reinforcing cloth with a sol-gel ceramic binder. The composite is particularly useful as a high strength, high temperature insulation material.

Abstract: Like-new golf balls are made from used golf balls by first reducing the diameter of the used ball, to provide an intermediate ball, and then molding a new dimpled cover on the ball. The diameter of the used ball is uniformly reduced by compression molding or by grinding.

Abstract: The invention relates to a flat molding produced by the injection molding technique, in particular an identity card, chip card or the like, characterized in that it has different volume areas containing different plastic components and formed and disposed so as to be distinguishable from one another visually and/or by measuring technology.

Abstract: In a multilayer bottle having at least two layers including an outer layer and an inner layer according to the present invention, the inner layer and the outer layer adjacent thereto are separable from each other at a body of the bottle while the inner layer and the outer layer are adhered to each other at least a part thereof in order to prevent the deformation of the bottle due to the reduction of a pressure in the bottle. When the pressure in the bottle reduces due to the volatilization of a content in the bottle or due to the discharge of the content by a pump and the like, the inner layer is separated from the outer layer and is crushed in the form of a bag, so that the outer layer is not deformed at all.

Abstract: A vascular prosthesis is formed from a luminate vessel by precipitating onto the vessel a sheet of polymer from a solution including an organic solvent and precipitable polymer, and forming an aperture in the sheet, the aperture communicating with the lumen of the vessel.

Abstract: A method for molding silicone foam into an article having the features of a designated object. The method includes the steps of introducing a silicone foam mixture into a first mold having a first cavity, wherein the silicone foam mixture forms a first molded object that has a shape which is representative of the first cavity; removing the first molded object from the first mold; pressing the first molded object into a second mold that has a second cavity, which has a basic profile that is representative of the article, the first molded object forming a layer of foam on the top edge of the second mold; cutting the layer to form an opened celled surface on the top surface of the first molded object; and releasing and removing the first molded object from the second cavity. The opened celled surface acquires the configuration that is representative of the second cavity, while the first bottom surface returns to the shape of the first cavity.

Abstract: A method of making microstructure bodies of plastic material. A microstructured plate-like base body which is made by any known molding procedure and which has a first side serving as a first reference plane and a second side which has plastic microstructures projecting therefrom is covered at its second side with a material layer that engages the microstructures, whereupon the material layer is machined to provide a second reference surface parallel to the first reference surface and the base body is then machined parallel to the second reference surface to expose the microstructures projecting therefrom and the material layer is finally removed selectively with respect to the plastic material to release the microstructured bodies.

Abstract: A method of producing a pattern shaped article includes the steps of forming at least two different courses of dry particles overlaid on a base surface; using an air flow controller having either a suction port or a blow port or both a suction port and a blow port to effect an air flow to form a cavity corresponding to a pattern expression in at least a lower dry particle course by removing a portion of the lower dry particle course under control of at least one parameter among air pressure, air flow rate, air flow speed, air flow direction, air flow pulsation, air flow intermittence, suction port size, blow port size, suction port position and blow port position; collapsing particles of an upper dry particle course of a different type of dry particles into the cavity and allowing the particles to set into an integral mass.

Abstract: A process for producing, by compression molding, an insulator having a core and a housing consisting of a sheath portion and at least one shade portion around the sheath portion, including the steps of: (A) preliminarily forming a rubbery layer around an outer periphery of the core to obtain a preliminarily molded body by extrusion molding, (B) placing the preliminarily molded body between at least two mold units of a mold; (C) forming a compressed molding by compression molding said preliminarily molded body in a given shape inside a cavity defined by the at least two mold units; and (D) curing the resulting molding. An apparatus is also disclosed for producing such an insulator by compression molding, which apparatus includes (A) a preliminary molding unit, (B) a molding unit form forming a compressed molding from the preliminarily molded body in a given shape by using a mold, and (C) a heater for curing the rubber in the rubber layer.

Abstract: A method of forming an interconnect including the steps of providing a processing substrate, adhering a first electrically insulating layer to the substrate, forming an electrically conductive pattern on the first electrically insulating layer, forming a second electrically insulating layer adhered to the first electrically insulating layer with the electrically conductive pattern between the first and second electrically insulating layers, forming connections to the pattern and then removing the adhered first and second electrically insulating layers and the electrically conductive pattern from the substrate to provide a freestanding film.

Abstract: A synthetic reinforcement having a plurality of recesses on a surface to facilitate adhesion to wood structural members and a process for making the same is disclosed. The synthetic reinforcement is comprised of a plurality of continuous fibers that are maintained in position by a resin encasement. The surface of the synthetic reinforcement is characterized by recesses that are located in a generally random pattern, which increases the surface area of the resin encasement. The synthetic reinforcement is connectable to wood laminae or itself with commercial grade adhesives such as the resorcinol resins, which are suitable for adhering the wood laminae together.

Abstract: A method for fabricating an ink jet recording head in which at least liquid channels, discharge ports and a ceiling plate for the formation of an ink liquid chamber are laminated on a substrate having ink discharge energy generating elements arranged on its surface, characterized in that said ceiling plate is formed of a high molecular resin having dispersed water-repellent grains composed of fluoro-oligomer, fluoropolymer, or fluorinated graphite.

Abstract: When forming a molding strip of varying cross-sectional shape along its length, lengths for finishing into molding strips are extruded with a prescribed cross-sectional shape through an extrusion port provided in the dies, before removing superfluous portions from the molding strip proper, wherein superfluous portions is extruded using a different resin material which is incompatible with that used for extrusion of the molding strip proper for later removal of said superfluous portions made of the different incompatible resin material from the molding strip proper.

Abstract: Inorganic composite membrane containing molecular sieve crystals, the membrane having a macroporous support to which molecular sieve crystals and modifications thereof have been applied substantially as monolayer, the crystals have been oriented to a substantial extent, such that the pores of the sieve crystals form a significant included angle with the support surface, the membrane has a gastight matrix present between the crystals.

Abstract: A method is disclosed for forming a reinforced plastic skin for an automobile interior trim structure. The method includes the steps of supplying a plastic material onto a mold surface, heating the plastic material to fuse it into a unitary layer, embedding a reinforcing material into the layer, and cooling the plastic and reinforcing materials. The method can be used to reinforce an air bag door cover by incorporating a tear seam into the plastic layer and embedding the reinforcing material into the layer such that it surrounds the tear seam. The reinforcing material aids in rupturing of the cover along the designated tear seam during deployment of the air bag. Also disclosed is an air bag door cover formed in accordance with the disclosed method.

Abstract: A method for manufacture of a plastic credit card includes steps of providing a mold with two shells. When the mold is closed the shells have opposed faces defining a cavity for producing the card. The general outline of the card is defined by the peripheral edges of the mold faces. An image support is placed in each shell; the molds are brought together. Then the plastic is injected to fill the mold and form the card. Plastic is delivered through a mold face and the inflowing plastic forces the respective image supports against opposite mold faces. After cooling, the mold card, now decorated on two faces, is removed from the mold.

Abstract: Plastic panels which are useful as automotive interior trim panels, interior door panels and the like decorative and structural panels, are made by a method which integrates insert sections in the surfaces of the panels and eliminates insert edge trim molding strips. The method includes positioning inserts into a mold, adding plastic to the mold to form a thin plastic sheet, presized blank, then removing the plastic sheet portions with the inserts; next, positioning the blank in a mold against a mold face and molding in situ and simultaneously bonding a plastic substrate against the blank and the exposed surface of the insert. Alternatively the blank can remain in the same mold and a suitable mating half of the mold can close off the plastic sheet and the plastic substrate can be injected or poured into the mold.

Abstract: Making patterned electrically conductive structures, such as circuit elements, in single or multiple laminar form. The basic laminar structure is made by forming and filling an intaglio pattern in a non-conductive sheet with solidifiable electrically conductive material in pliable form, bonding the respective conductive and non-conductive materials in place and together, and removing the sheet portion underlying the conductive pattern to leave both the conductive and the non-conductive materials bonded laterally as a single lamina. Face-to-face juxtaposition of like or unlike laminae so made provides built-up or laminated products.

Abstract: A ferrite chip bead includes a ferrite substrate, a plurality of outer electrodes formed at opposite sides of the ferrite substrate, and a plurality of conductive leads each extending transversely through the ferrite substrate and having opposite ends protruded outwardly of opposite side surfaces of the ferrite substrate and connected to corresponding outer electrodes. Conductive leads are embedded in the ferrite substrate by introducing conductive leads in a central portion of a nozzle for extruding the ferrite substrate such that the conductive leads are embedded in the ferrite substrate being extruded, or by introducing conductive leads between ferrite substrate sheets being fed to be bonded together for forming the ferrite substrate such that the conductive leads are interposed between the ferrite substrate sheets being bonded. The ferrite chip has no tendency for outer electrodes to short-circuit from the ferrite substrate upon carrying the chip bead on a circuit board.

Abstract: Plastic panels which are useful as automotive interior trim panels, interior door panels and the like decorative and structural panels, are made by a method which integrates insert sections in the surfaces of the panels and eliminates insert edge trim molding strips. The method includes bonding at least the edge portions of the inserts upon a thin plastic sheet, pre-sized blank, then removing the plastic sheet portions that overlap the insert within the bonded portions; next, positioning the blank in a mold against a mold face and molding in situ and simultaneously bonding a plastic substrate against the blank and the exposed surface of the insert. A substantially continuous, channel forming means, such as a narrow rib or a groove, on the mold face, is overlapped by the bonded insert edge portions and sheet portion, which are folded by said means to form a narrow, relatively deep channel. The insert edges are part of and, consequently, are concealed within the channel.

Abstract: A process for renewing the refractory lining of a ladle for casting steel and of similar metallurgical vessels. While the ladle (10) is still hot, the slag (S) still adhering to the inner surface (26) is melted off from the remaining lining (2) with the aid of a high-temperature burner (9) operating under reducing conditions and allowed to run out of the ladle (10) in the molten condition. After cooling, the glassy surface of the remaining lining (2) is roughened. The new refractory lining (30) is then applied by casting, with the aid of a template.

Abstract: An elastic permeable material and method of making same involves a board-like basic structure made of a foam material having therein close cells. The basic structure is provided with a plurality of recesses which are filled with an emulsified foam body having therein open cells. The basic structure is subjected to a heating and then a curing before the top and the bottom layers of the basic structure are peeled off so that the recesses become through holes. The basic structure is used as a main framework while the foam bodies embedded in the through holes form a permeable framework. The elastic permeable material is provided thereon a permeable outer covering adhered thereto. The basic structure is heated under a pressure so as to bring about a reduction in the thickness of the basic structure, thereby resulting in a formation of corrugated surface of the elastic permeable material.

Abstract: To remove a layer of thermoplastic material, particularly of polyethylene, adhering to a substrate, particularly a strip of aluminum, there is directed against a region of the layer of thermoplastic material (2) a shaped jet (10) of hot inert gas, containing for example principally helium, to melt the thermoplastic material and the jet is displaced relative to the coated substrate to push back (11) the melted thermoplastic material. The gas or the gaseous between 300.degree. C. and 700.degree. C., by an electric resistance (20), adjacent the ejection nozzle (4).

Abstract: An apparatus and method for fabricating accurate, numerically defined curved surfaces and volumes comprising a skeleton framework having a plurality of bulkheads fixed in spaced relationship with each other, each of the bulkheads having an equal number of boreholes passing through the outer perimeter thereof so as to provide a set of selected boreholes. A flexible spline having a memory is passed through each set of mating boreholes and is secured with the boreholes after the splines have reached their static states. The resultant framework is encased in a cured polymer and the polymer is trimmed and faired between the outer edges of the splines.

Abstract: A gasketing device for forming a molded interior trim component for a vehicle utilizes a flexible planar gasket compressed between mold halves to prevent foaming material from entering the gasket area. The gasket is adapted to be secured to a structural insert and has a flexible peripheral edge that seals against the inside surface of a bezel on the insert. The gasket extends through the opening defined by the bezel to seal against a skin shell. The method includes mounting the gasket on the insert. The insert and gasket are placed on a mold half with an opposing mold half having a skin shell thereon. A foaming formulation is placed between the skin shell and insert and allowed to foam about the gasket to secure the insert to the skin shell. The product is removed, the skin shell over the gasket cut and peeled away to form an opening in the shell dimensioned smaller than the dimensions of the peripheral edge of the gasket.

Abstract: A method of manufacturing a ring-shaped hydraulic seal (10) produces a cylindrical sealing surface (12) having portions (24) formed of a plastic material and portions (26) formed of an elastomeric material. The method includes the steps of forming a plastic ring (30) and molding an elastomeric material into a cavity (50) in the plastic ring (30). The cylindrical sealing surface (12) is formed by grinding away the material of the ring (30) to expose a surface (26) of the elastomeric material which is contained in the cavity (50) in the ring (30). The plastic portions (24) of the cylindrical sealing surface (12) are defined by the ground surface (82) of the plastic ring (30). The elastomeric portions (26) of the cylindrical sealing surface (12) are defined by the exposed surfaces (26) of the elastomeric material.

Abstract: A method for repairing a hot-blast, long-time cupola furnace by removing residual slag and relining the cupola furnace including feeding liquid nitrogen to the cupola furnace immediately at the end of a smelting operation and simultaneously with the feeding of the liquid nitrogen, removing residual slag from the furnace. The furnace is cooled with liquid nitrogen until the furnace reaches a temperature of less than or equal to 40.degree. C. after which the furnace is relined with fresh refractory tamping compound.

Abstract: A method of making a catheter is provided. The catheter has an atraumatic portion at the distal end of a catheter having the stiffness and torque resistance required of a catheter such as that suitable for angiographic uses, typically in French sizes on the order of about 2 to about 8. The atraumatic tip portion has a generally co-axially layered structure. An inner layer is made of soft atraumatic polymer, and an outer layer is made of a polymer to impart needed stiffness and torque properties to the catheter. In the preferred embodiment, a portion of the distal tip material of the harder outer layer is removed, thereby exposing the inner, atraumatic material for initial engagement with internal body passageways.

Abstract: Hollow fiber membranes can change dimensions upon drying or other processing creating leaks in tubesheets formed on fiber bundles. An adherent layer is formed in contact with an inner surface of each tubesheet and the fiber membranes therein in such a manner as to fill gaps formed between the hollow fiber membranes and each tubesheet during the drying or processing of the hollow fiber membranes and tubesheets. Preferably, the adherent layer is cast from a diglycidyl ether of bisphenol A containing an acrylo-nitrile-modified polyamine curing agent and the hollow fibers are cellulose ester.

Abstract: A process for forming a poured slab, preferably of concrete, which has different colored portions. The process includes (a) pouring a wet concrete mixture of cement particles, sand particles and gravel particles into a horizontal mold cavity having a stepped mold bottom surface, (b) curing the mixture to produce a slab with a roughly horizontal rear surface and a stepped front surface corresponding to the mould bottom surface, and (c) mechanically removing the cured mixture between a cut plane generally parallel the rear surface through the slab and the front surface. The resultant slab has different portions with different coloration and appearance due to the cut plane passing through portions of the concrete having different proportions of cement, sand and gravel particles.

Abstract: A method of manufacturing a randomly patterned floor covering having contrastingly-colored zones from a preform of rubber in which the preform is cut in pieces, each of which are molded into a blank having projections extending from a top side of the blank in relief-like fashion, solidified by vulcanization and then machined by cutting only in the region of the projections. The rubber forming the contrastingly-colored zones is mixed with contrastingly-colored particles in an amount of at least ten percent by weight. These particles are substantially free of flat surfaces and are in, at least, an advanced state of vulcanization. The particles located in the projections extending from the top side of the blank are exposed during the cutting step.

Abstract: An apparatus and method for fabricating integral three-dimensional objects from successive layers of photoformable compositions by exposing the layers of the composition through a detachable flexible transparent film, one side of the film being in contact with the composition and the other side of the film with a rigid transparent plate, which guides and supports the film.

Abstract: A method for repairing voids in a finished urethane foam product having a typical backing insert or retainer wall, the method including the steps of forming a hole through the retainer wall adjacent the void; inserting a small elastomeric sheath through the hole into the void; injecting a urethane or silicone elastomer into the sheath to fill same to conform to the void; and sealing off the hole with a suitable plug which may be sanded flush with the retainer wall outer surface.

Abstract: A process for improving chemical and physical adhesive properties of an adhering surface of an unsaturated polyester resin to be adhered onto an article prepared from the unsaturated polyester resin which includes:laying a cloth on a portion of a mold, the cloth having a strong adhesivity for the unsaturated polyester resin;impregnating the cloth with the unsaturated polyester resin and leaving the impregnated resin on said mold for hardening for a given time to form a sheet; andstripping the cloth which is impregnated with the hardened unsaturated polyester resin from the unsaturated polyester resin to form an irregular or rugged adhering surface.

Abstract: Method of for continuously manufacturing a plurality of kinds of elongate articles with basically same and slightly different cross-sections, such as upper and side segments of automobile molding members. The method employs a single die plate formed with a common orifice and at least one additional orifice, as well as a device for selecting and controlling operational modes of the apparatus. The device may comprise a movable guide member which is movable between different positions corresponding to respective operational modes of the apparatus, and serves to guide synthetic resin material extruded from the additional orifice. The guide member maintains in its one position a spaced relationship of synthetic resin materials extruded from the orifices to form one kind of elongate articles, and causes in another position the synthetic resin materials to adhere with each other to form another kind of elongate articles.

Abstract: Plastic panels which are useful as automotive interior trim panels, interior door panels and the like decorative and structural panels, are made by a method which integrates insert sections in the surfaces of the panels and eliminates insert edge trim molding strips. The method includes bonding at least the edge portions of the inserts upon a thin plastic sheet, pre-sized blank, then removing the plastic sheet portions that overlap the insert within the bonded portions; next, positioning the blank in a mold against a mold face and molding in situ and simultaneously bonding a plastic substrate against the blank and the exposed surface of the insert. A substantially continuous, channel forming means, such as a narrow rib or a groove, on the mold face, is overlapped by the bonded insert edge portions and sheet portion, which are folded by said means to form a narrow, relatively deep channel. The insert edges are part of and, consequently, are concealed within the channel.

Abstract: Producing an encapsulated glazing unit having a weather-stable film on an exposed surface of the gasket. There is provided a two-part mold whose sections cooperate to define a mold cavity for receiving the peripheral margins of the transparent glazing unit upon which the gasket is to be formed. A sheet of the weather-stable film is positioned over the mold section having the portion of the cavity which defines the surface to which the film is to be applied. With the mold closed, a flowable gasket forming material is injected into the mold cavity behind the film to deform the film into conformity with the mold surface. As the gasket cures in situ, the film fuses to its surface. The encapsulated unit is removed from the mold and the excess film is trimmed from around the gasket.

Abstract: A technique is provided for removing foam mandrel material from a stiffener section of a composite structural member as is employed in lightweight aircraft skin structures. The technique involves the direct pressure glass bead blasting of the mandrel material. By mounting a blasting nozzle within a rubber hose of larger diameter, an airstream containing glass beads may be directed outwardly through the nozzle while evacuating pressure is created in an annular passageway between the hose and the nozzle to evacuate mandrel foam particles as well as spent glass beads. The result is a clean channel within the stiffener section.

Abstract: A tile board made from a one piece sheet having top and bottom portions of contrasting colors. Grooves are machined through the top layer to expose strips of the bottom layer. The exposed strip divides the top layer into tile sized members which simulate inlaid tiles having beveled edges. The exposed strips of the bottom layers simulate recessed grout lines. Machining of the grooves through the top layer simultaneously forms the simulated tiles and simulated grout lines in the plastic sheet. The tile board can have a bent edge section to provide a finished tile look spanning a corner of two adjacent walls.This is a Continuation-in-Part of application Ser. No. 906,326 filed Sept. 11, 1986, now abandoned, which is a Continuation-in-Part of application Ser. No. 575,217 filed Jan. 30, 1984 (now abandoned).

Abstract: Process of manufacturing a cryogenic regenerator including a plurality of channels for conducting a working fluid, including the steps of providing a cylindrical forming member having a longitudinal axis and a plurality of peripheral slots displaced axially and oriented substantially parallel to the longitudinal axis of the cylindrical forming member, or having a continuous spiral peripheral slot of sufficiently small pitch such that the convolutions thereof are oriented substantially parallel to such longitudinal axis; providing epoxy which is relatively flexible upon hardening, loading the epoxy with thermally conductive material for enhancing the radial thermal conductivity of the cryogenic regenerator, and applying the epoxy to the periphery of the cylindrical forming member to fill the plurality of slots or the spiral peripheral slot with the epoxy and to form a radial layer of the epoxy of a generally first radial thickness allowing the epoxy to harden and thereafter reducing the radial thickness of the

Abstract: Ceramic insulation has a mat of intersecting, discrete ceramic fibers bonded with a sol-gel glass binder. A fabric-reinforced glass coating is bonded to at least one surface of the mat. The insulation is prepared by forming a slurry of ceramic fibers, molding the slurry to form a soft felt mat, drying the mat, and incrementally introducing the binder into the mat with a multiple-impregnation technique, which controls shrinkage of the ceramic fiber mat. The fabric-reinforced glass coating is formed by applying a glass fiber cloth to a surface of the ceramic fiber mat and coating the same with a powdered glass. The powdered glass is melted and cooled.The process provides a layering technique that permits formation of a continuous fibrous structure having layers that impart distinct characteristics at desired regions within the structure.

Abstract: An aluminum or aluminum alloy profiled section has one or more insulated electrical conductors. Such a profiled section includes at least one linear electrical conductor parallel to the profiled section, formed by the same material as the latter and insulated electrically in a solid insulating filling, a bare surface of the conductor and a bare surface of the filling being covered if required by a second insulating filling.

Abstract: For facilitating the quality control examination of the metal plating of holes in printed circuit boards, several test pieces are cut from circuit boards. Each test piece includes within its perimeter at least one, and preferably a row of at least three metal plated holes. The perimeter of each test piece, as cut, is notched with outwardly opening grooves so as to fit in a fixture in a preselected disposition. Several test pieces are places in a fixture, which serves as a mould for plastic material. After the plastic material hardens around the test pieces, a portion of the composite of test pieces and hardened plastic is sliced off, at a level which exposes half of each metal plated hole. The grooves allow great precision and simple handling.

Abstract: A process for making a glazing product which includes forming a gasket on a sheet of bilayer glass with a self healing transparent elastic plastic layer bonded to one side of the glass. A removable protective material is applied to the plastic layer. The assembly is placed in a mold cavity and a plastic material is injected into the mold cavity to form a gasket. The protective material is removed from the plastic layer after the gasket has formed.

Abstract: After a mortar layer is formed on the surface layer of placed concrete, an ultrasonic vibrator is caused to vibrate while being pressed against the mortar layer surface, and a thin surface layer is scraped off, obtaining a dense water-shielding layer. Mortar with a low water-cement ratio is spread onto the surface of the water-shielding layer, and adhesion between the mortar and the water-shielding layer is strengthened by using the ultrasonic vibrator. The pressing force of the ultrasonic vibrator is then increased to make the mortar and the water-shielding layer densely integrated together, thereby forming a hard concrete surface excelling in abrasion resistance.

Abstract: Continuous rod-like molding having a FRP core and an outer skin of thermoplastic resin is shaped by introducing the molding into a passage of a heated die, the passage having a diameter slightly smaller at an exit thereof than an initial diameter of the molding, plasticizing the thermoplastic resin by passing the molding through the passage, thereby removing a part of the outer skin, and solidifying the thermoplastic resin, thereby obtaining a product having a diameter equal to the diameter of the exit of the passage.

Abstract: A method for the manufacture of artificial teeth, either replacement whole teeth or crowns, whereby a tooth is produced by machining from a layered block of synthetic plastics materials, the layers being of predetermined varying color (hue), chroma, value and translucency to simulate the pulp, dentine and enamel layers in a real tooth, thereby providing an artificial tooth with the distribution and depth of color of a real tooth. The process provides for varying the tooth color by milling the tooth from a different section of the layered block to vary the thicknesses of the layers, at least at the labial, mesial, distal and occlusal surfaces, so as to obtain a custom tooth matched very closely to a patient's real tooth color and pattern. The process permits the manufacture of an artificial tooth from materials with a hardness closely matching that of a real tooth to provide similar wear properties.

Abstract: A mold assembly for molding vinyl skin shell-covered and foam-filled products, such as an automotive instrument panel, wherein waste portions of the shell and foam are eliminated from the molded product. This eliminates having to manually trim such portions from the finished product after molding. Specifically, compressible foam or silicone rubber gaskets or spacers of predetermined shaped, such as the shape of an opening suitable for a radio speaker, are placed in the mold and compressed between the mold lid and the bottom surface of the mold cavity.

Abstract: A process for applying a permanent filled engraved identification to the surface of an object such as a paving brick which is made of porous material.

Abstract: A method is provided for making a splittable introducer catheter by co-extruding two different polymers of differing solubilities, so that v-shaped strips are formed on each side of the catheter wall which may be easily stripped from the main catheter tube. This leaves an introducer catheter which is easily split along the narrowed v-shaped grooves on diametrically opposite walls of the catheter.