Abstract: A method for coating a surface with a magnetic composite material exhibiting distinct flux properties due to gradient interfaces within the composite. Surfaces coated with such a composite can be used to improve fuel cells and to effect improved transport and separation of different species of materials. A wide variety of devices can incorporate such composite-coated surfaces, including separators, fuel cells, electrochemical cells, and electrodes for channeling flux of, or for effecting electrolysis of, magnetic species.

Abstract: A improved method of manufacturing plastic containers with molded-in metal inserts is employed to secure metal inserts to an interior of a rotary mold so that the inserts are automatically released from the mold when the article is removed from the mold. The method includes providing a mold having a magnet on the interior surface thereof, placing a metal insert in contact with the magnet, charging the mold with a quantity of a resin, biaxially rotating and heating the mold to melt and distribute the resin, cooling the rotating mold and removing a finished container with a molded-in metal insert. The mold rotates biaxially, about a first axis and a second axis which is perpendicular to the first axis. Preferably, the mold is constructed with magnets projecting from the outside through to the inner surface. The magnets present a concave curvate inner facing surface which mates with a convex curvate outer surface of a metal insert.

Abstract: An apparatus is provided including an endless conveyor and a plurality of elongated mold elements are mounted from the conveyor and project laterally outwardly of the latter. The apparatus defines coating, heating, and cooling stations through which the mold elements are successively moved and the coating station includes structure whereby the outer end portions of the mold elements may be coated with plastisol. The heating station includes structure by which the mold elements, with the plastisol coating thereon, may be exteriorly and interiorly heated to the cure temperature of the plastisol, the cooling station includes structure for externally and internally cooling the mold elements.

Abstract: A rotational molding oven for forming an object from a mold. The oven includes a cavity for retaining the mold, a burner for heating the cavity and melting the resin and a device for rocking the mold between −45° and 45° from a horizontal plane. The rocking device is outside, extending into the cavity, maintaining the mold in the center of the cavity. The rocking device facilitates distribution of resin within the mold and improves thermal flow of heat within the cavity thereby increasing thermal efficiency and minimizing the size of the cavity. The rocking device includes a first track outside the cavity, a carriage assembly, a drive assembly connected to the carriage assembly and a guide assembly connected between the first track and carriage assembly for translating up and down the first track, causing the carriage assembly to move therewith and the mold to rock about the central axis of the cavity.

Abstract: A rotomolded hydraulic reservoir includes a plastic container body defining a container cavity for receiving hydraulic fluid and forming a filter cavity in fluid communication with the container cavity. An insert, such as an aluminum bushing, is molded in the container body adjacent the filter cavity and a removable filter element positioned with the filter cavity and coupled to the insert.

Abstract: A method and apparatus for manufacturing pharmaceutical capsules use an aqueous solution of a thermogelling cellulose ether composition and use capsule body pins and capsule cap pins as molds. The method involves heating the pins, dipping the pins into the solution to cause the solution to gelatinize on the surface of the pins, removing the pins and drying the gelatinized solution on the surface of the pins to form capsule bodies and capsule caps. Pins are heated pre-dip and post-dip to facilitate gelating. Counterflow air is applied to provide drying from the inside. Capsule parts are removed by gripping. Capsule parts may have a thick wall and a stiffening ring.

Abstract: There is provided a plastic working machine for plastically working a tube by employing tube holding and spinning means for holding and spinning the plastically workable tube around the axis of the tube and first and second plastic working tools which face to each other so as to pinch the tube in the radial direction of the tube and which are movable along the radial and axial directions of the tube while being pressed against the tube. The plastic working machine executes a step of plastically working the tube by the first and second plastic working tools by continuously spinning the tube around the axis thereof and by applying compressive load or tensile load along the axial direction of the tube to the tube.

Abstract: Multiaxis rotational molding apparatus (11) includes a plurality of spaced generally horizontally oriented arm members (17-20) each having one end (21) extending from an upstanding frame section (22) with one mold assembly (32-35) rotatably mounted adjacent a free end thereof. Each mold assembly includes a plurality of separable mold sections (36) including plate sections (38). A plurality of movable elongated mixing chambers (47-49), each including a plurality of adjacent axially aligned rotatable driven mixing sections (52-54). A control portion (15) includes an indexing mechanism (67, 68) sequentially orienting a dispenser of each mixing chamber with each mold assembly to control formation of molded structures continuously in a preselected multiaxis molding profile. Also, a method of forming molded structures with the molding apparatus is disclosed.

Abstract: A large molded article block free from distortion and residual stress can be obtained by means of a method of producing a polytetrafluoroethylene molded article by compression-molding a polytetrafluoroethylene powder to form a preform and baking the resulting preform with rotating. Furthermore, a film or sheet having less curling and wrinkle can be obtained by cutting the molded article block.

Abstract: The use of comminuted, recycled glass powders as a filler in molded plastic parts is disclosed. The recycled glass powder has non-uniform, rounded edges and is free from contaminants such as grinding compounds, metals, inorganic, and organic waste materials. The recycled glass powder filler can be used with a variety of different thermoplastics and thermosetting plastics commonly used to in injection molding and blow molding of plastic parts.

Abstract: A bulk polymerized grafted and crosslinkable thermoplastic polyolefin powder composition having elasticity and flexibility properties, which is in the form of a powder intended for the production of flexible coatings by free flow over a hot mold, characterized in that it contains:

Abstract: The present invention includes a mold apparatus for facilitating replacement of rotatable molds therein. First and second frames are provided forming a plurality of mold cells and each mold includes an upper and a lower mold section. The upper mold section is removably coupled to the upper frame, while the lower mold section is removably coupled to the lower frame. Using this arrangement, a mold may be removed by detaching all connections between it and the frames, while maintaining the frames closed. Similarly, a mold may be inserted into a mold cell and connected to the frames while maintaining the frames closed. The removal and insertion operations may be performed radially or axially, depending on frame configuration.

Abstract: A composite with a thermoplastic matrix and fiber reinforcement is made by rotation of an exit die about a roving of continuous fiber in the presence of a thermoplastic melt. The rotation causes opposing inner and outer helical flow conditions which reduce the melt viscosity of the polymer by shear thinning while dragging and directing the polymer into the fiber roving thereby wetting and dispersing the fiber. A composite structure is formed with a polymer rich skin and a core region of unidirectionally aligned polymer and fiber. The polymeric skin is composed of helically aligned polymer chains which are coiled by the rotation around the core to compress the core region and enhance fiber wet out.

Abstract: An anode is embedded in an electrolyte layer applied to the surface of a structure such as a pipe section to provide an ionic conductive path between the anode and structure to supply cathodic protection to the structure, where the natural environment may not provide a continuous electrolyte. The anode is comprised of a material normally used as a cathodic protection anode material, such as, an expanded valve metal mesh or ribbon having either an electrochemically active coating or noble metal coating, or a sacrificial anode metal alloy. The anode material is made continuous from one end of the structure to the other and may be connected to a common bus wire from one end to the other. The anode and structure to be protected are connected using wires to a DC power supply that causes cathodic protection current flow to the structure in the case of an impressed current system. No separate power supply is needed in the case of a galvanic or sacrificial anode system.

Abstract: A method for manufacturing thermoplastic tubes from hollow thermoplastic sleeves by a variety of different manufacturing processes. The machine used in the method is a single apparatus having an indexing device with a plurality of mandrels for holding hollow thermoplastic sleeves for the purpose of transporting the same around a closed manufacturing path. The method involves advancing sleeves around the closed manufacturing path to form tubes from the sleeves.

Abstract: Prophylactic devices are made in an inert atmosphere by cooling mandrels on which the devices are to be deposited, dipping the mandrels into a polymeric material in a solvent/carrier and a mold release agent, rotating the mandrels during and after the dipping, and evaporating the solvent after dipping. The apparatus includes an air lock between a section in which these functions are performed and a section located in an air atmosphere for removing the devices from the mandrels, followed by cleaning the mandrels for use in a subsequent production run for making devices.

Abstract: A rotational molding method is provided consisting in a first method of spraying the inner mold area with an acrylic polyethylene alloy prior to loading the resin into the mold. The mold is then heated, rotated and cooled to form the molded part. The part is provided with a shinier and harder surface layer as compared to previous rotational molding methods. In a second method, in lieu of spraying, the acrylic polyethylene alloy is loaded into the mold with the resin. In the third and fourth methods, a drop box is provided for releasing resins into the mold. Other materials, in addition to acrylic polyethylene, can also be used with the various methods.

Abstract: An article including a panel-like structure mountable in an automobile vehicle to form a part of the interior thereof and conceal a secondary restraint system, and a process for making the same are disclosed. According to this process, an outer layer is established on a first mold surface, with the exterior surface of the outer layer having an opaque visual appearance and a configuration complementary to the first mold surface. A casting composition is then rotationally casted onto an inner surface of the outer layer to create an inner layer of a predetermined thickness while restricting the gel thickness along an elongated structurally weakened tear seam. The casting composition is then fused. The outer layer and inner layer collectively define a layered composite structure, with the outer layer presenting the same opaque visual appearance to the exterior surface thereof unaffected by change in the inner layer thickness so that the structurally weakened tear seam is hidden from view.

Abstract: An article of manufacture and method of making and implanting the article made of a polyolefin star or linear copolymer are disclosed in which the polyolefin copolymer is biostable and crack-resistant when implanted in vivo. The polyolefin copolymer is the reaction product of a rubbery component which when homopolymerized produces a polymer having a low level of hardness, and a hardening component which when homopolymerized produces a polymer having a high level of hardness. The polyolefin copolymer is elastomeric, has a hardness intermediate the low and high levels of hardness, and has a backbone in which the majority of polymer linkages along the copolymer chain are alternating quaternary and secondary carbon atoms.

Abstract: A method of making a container assembly comprises the step of molding a container body over a portion of a plastic fixture. A plastic fixture is disposed in the mold. The mold has an inner surface defining an outer surface of a container. The fixture includes an opening and a portion having at least one ridge on a surface which is to be embedded in the body of the container. The fluid plastic material is disposed in the mold. The plastic material is then molded over the mold inner surface and the fixture surface thereby forming the container body. The plastic material contacts the ridge and melts or softens the ridge. The ridge is then deformed forming a locking engagement between the container body and the fixture. As the plastic material cools and hardens, the plastic container body partially engulfs the fixture to provide a secure seal between the fixture and container body.

Abstract: A process for producing a nanoporous polymer film of no greater than 10 micron thickness having low dielectric constant value, including the steps of: (a) providing a polymer in a solution with at least two solvents for the polymer in which a lowest boiling solvent and a highest boiling solvent have a difference in their respective boiling points of approximately 50° C. or greater; (b) forming a film of the polymer in solution with at least the two solvents on a substrate; (c) removing a predominant amount of the lowest boiling solvent; (d) contacting the film with a fluid which is a non-solvent for the polymer, but which is miscible with the at least two solvents to induce phase inversion in the film; (e) forming an average pore size in the film in the range of less than 30 nanometers. The present invention is also nanoporous films made by the above process.

Abstract: Plastic hoods and dividers are provided for use with row crop heads. The hoods and dividers are single walled and self-supporting. The single-walled hoods and dividers are preferably manufactured through a rotational molding process wherein a non-stick coating, such as polytetrafluoroethylene, is attached to portions of the mold.

Abstract: A headed thermoplastic tube is formed solely from a thermoplastic extruded, stretched, sleeve by positioning the sleeve over a forming mandrel so the sleeve has an exposed portion. While rotating the forming mandrel which holds the sleeve, the inner surface of the exposed portion of the sleeve is heated above the glass transition temperature of the thermoplastic material to render the inner surface molten while the outer surface provides support for the exposed portion of the sleeve. The heated exposed portion is then shaped into a conical shape, such as by heating the outer surface, the rotation of the mandrel is stopped and pressure applied to the conical shaped exposed portion to form a headed thermoplastic tube. The headed tubes produced have a body portion, shoulder portion and neck portion, without any seams, all of which are formed from the starting thermoplastic extruded, stretched sleeve.

Abstract: A process for forming a product having multiple and well defined color patterns. In a first embodiment, the rotomolding process comprises a first step of using a first powder having a first color and a second powder having a second color which is different than the color of the first powder. The rotomolding process comprises a second step of placing the first and second color powders into a pre-determined pattern within a hollow cavity mold. The rotomolding process comprises a third step of placing the closed hollow cavity mold into the oven. The rotomolding process comprises a fourth step of heating the hollow cavity mold with no rotation for a first period defined by the heating time necessary for a layer of individual colors to melt in the desired pattern upon the inside surface of the hollow cavity mold.

Abstract: A tubular object manufacturing method comprising the steps of applying liquid heat-resistant resin containing an inorganic filler as desired onto an outer surface or inner surface of a core member which is a shaping mold to thereby form a coating layer, solidifying or hardening the applied liquid heat-resistant resin until the coating layer becomes strong enough to maintain at least a structure of the tubular object, and taking the tubular object out from the core member. In the method, liquid heat-resistant resin with a viscosity of 10 to 15000 poise at 25.degree. C. is continuously fed by means of a dispenser onto the outer surface or inner surface of the core member while rotating the core member, and a feeder part of the dispenser is moved in the direction of a rotation axis of the core member so that the fed liquid heat-resistant resin is helically wound to thereby form the coating layer.

Abstract: The invention concerns a process for producing multi-colored plastics, in which slush material is introduced into a mold which can be heated and rotated and has a molding surface. The colorant material comprises a plurality of coloring elements consisting of a colorant content and a transparent plastics cover surrounding the latter or a plastics matrix holding the colorant content together. The colorant content is left in the plastics casing or matrix during sintering and gelling.

Abstract: A method and apparatus for compression molding plastic articles including closures which includes providing co-acting sets of tools including a first set for moving a core and core sleeve into engagement with a cavity mold on a second set of tooling. An actuator is provided between the first set of tooling and a fixed upper cam. The second set of tooling includes an associated actuator supporting the cavity mold and associated with a lower fixed cam. A nitrogen cylinder in the second set of tooling provides for control of the compression molding force. In a preferred form, a plurality of sets of tooling are provided in circumferentially spaced relation on a rotating turret supported by a central column. A common manifold supplies the pressure at accurately controlled pressure to each of the nitrogen cylinders. A control system is provided for monitoring and changing the pressure.

Abstract: The present invention generally relates to a system for manufacturing horizontally precast panels of moldable material which panels require shaped surface patterns. More particularly, the invention relates to a system for manufacturing horizontally precast concrete panels formed of concrete, for use in vertical wall systems, with one or more shaped surfaces.

Abstract: A method of continuously forming an integrally molded structure in a multiaxis rotational molding operation includes the steps of rotating a multisection mold assembly (33) about at least three axes. A first freshly formed polymerizable mixture is flowed over surfaces of an enclosed mold cavity (36) within the multisection mold assembly. The flowing of the first mixture over the mold cavity surfaces and formation of a first resin (74) therefrom is monitored. A freshly formed rapidly gelling second polymerizable mixture (75) is flowed into the mold cavity to deposit a preselected quantity thereof into contact with a first preselected area of the first resin. A portion of the deposited second mixture is drawn as it is gelling toward another preselected area remote from the first preselected area to form therefrom a continuous support member (92) with structural integrity extending between the preselected areas of the first resin.

Abstract: An article including a panel-like structure mountable in an automobile vehicle to form a part of the interior thereof, and a process for making the same are disclosed. According to this process, an outer layer defining at least a portion of the exposed exterior surface of the structure is prepared by applying a water-dispersed composition containing a thermoplastic polyurethane and a heat-activated crosslinking agent onto a mold surface and thereafter drying the composition. Next, a composition comprising (i) a poly(vinyl chloride) resin and at least one plasticizer and/or (ii) a thermoplastic polyurethane resin material is gelled onto an inner surface of the outer layer while on the outer layer is retained on the mold surface. The gelled composition is then fused to form an inner layer interfacially chemically bonded to the outer layer. The inner layer with the outer layer chemically bonded thereto is united with the rigid substrate so that the rigid substrate serves to reinforce the outer layer.

Abstract: An apparatus requiring storage of a liquid that needs agitation includes a plastic tank that is rotationally molded around an agitation portion. In a preferred embodiment, an asphalt sealcoat application system has such a plastic rotary molded tank mounted on a powered vehicle or trailer and utilizes a pump connected to a hose and spray wand for application of sealcoat on an asphalt surface. The tank is preferably formed of low density polyethylene resin and the agitation portion includes a plurality of paddles and a shaft extending from the interior of the tank for mixing the sealcoat liquid. The polyethylene tank is rotary molded around the assembled agitation portion. The invention includes the methodology of molding the tank, a tank molded by said methodology, and the apparatus for accomplishing said methodology.

Abstract: Spherical particles having a diameter between 0.007" and 0.040" are formed from melt extruded thermoplastic material formed of blended and melt extruded thermoplastic and pigment.

Abstract: Centrifugal casting is used to establish a gradient profile of reinforcement particulate densities in a carrier matrix of a polymer resin and in an aluminum alloy. Cast disks of silicon carbide (SiC) reinforced resin and Al-Si/SiC particulate reinforced MMCs have been produced that show a gradient of SiC increasing from a denuded region adjacent to an axis of rotation of the disk to a maximum density at the periphery of the disk. An applied centrifugal acceleration applied by rotating the mold is used to establish an artificial settling of the particulate field in a homogeneous mixture of a fluid matrix and the particulates. The principle parameters in establishing a range of particulate densities in centrifugally cast particulate composites are the centrifugal acceleration applied and the length of time the matrix material remains in a liquid state. The magnitude of these parameters are determined by the specifics of a particular casting design.

Abstract: A method for treating a shirred food casing strand, having a diameter, a circumference, a longitudinal axis, an external surface and a hollow bore along at least a portion of said longitudinal axis, which comprises smoothing said exterior surface by rolling said strand between at least three rollers, all of which simultaneously contact said surface at different lines of contact. It has been found that the simultaneous use of at least three different lines of contact during rolling, as opposed to two lines of contact, as might be applied by rolling between plates, helps preserve and even improve the roundness of the strand. The invention further comprises an apparatus for practicing the method of the invention which comprises at least three rollers arranged so as to contact the exterior surface of the strand and means for rolling the strand between said rollers. The invention further includes a shirred food casing strand having an external surface simultaneously rolled at at least three lines of contact.

Abstract: A method for manufacturing a sheet molded part by polymerization of lactams in a sheet mold includes the steps of placing a fiber composite material into a sheet mold having large plane surfaces and fixedly positioning the fiber composite material in the sheet mold. Subsequently, the lactams are introduced into the sheet mold and the lactams are polymerized.

Abstract: A method for treating a roller cover includes the steps of positioning an element with respect to a roller cover and removing a portion of the roller cover with said element to form a pattern on said roller cover. The process for treating roller covers for a paint roller may also includes the steps of providing a surface, forming a pattern on the surface, heating the surface, and contacting the roller cover with the heated surface. The heated surface is a metal. The heat is transferred from the heated metal surface to the roller cover when the heated metal surface contacts the roller cover. The heated surface sears or melts the nap of the roller cover. The surface can be provided with a pattern so that a pattern can be placed into the nap of the roller cover. An apparatus used to treat the surface of a roller cover includes a surface having a desired pattern therein. A holder for a roller cover holds or presents the roller cover to the surface. A heater is attached to the surface.

Abstract: A method for producing zirconia fused cast refractories, which comprises casting zirconia fused cast refractories containing at least 33 wt % of a ZrO.sub.2 component utilizing a mold, wherein the mold is rotated on a rotation axis, so that at least a portion of a meltage of raw material poured into the mold, is cooled to solidify under a centrifugal force of at least 1.2 G.

Abstract: In order to produce tubular moldings of high-temperature superconducting material based on oxides of bismuth, calcium, strontium, copper and optionally lead, a homogeneous melt of the oxide mixture in a predefined stoichiometry having temperatures from 900 to 1300.degree. C. is made to flow into a casting zone. The casting zone, as a function of its internal diameter, rotates at from 200 to 1500 rpm about its axis which is inclined by at least 15.degree. with respect to the horizontal. The solidified molding is taken from the casting zone and annealed for from 4 to 150 hours at from 700 to 900.degree. C. in an oxygen-containing atmosphere.

Abstract: A high speed plastic-forming process forms a curved wall section with a compound radius along the outer edge of a sheet of plastic foam material. The process includes first die cutting the flat sheet material to a shape having an initial edge curvature, followed by securing the die cut piece to a carousel which passes the curved outer edge section of sheet material past heaters that controllably heat the top and bottom surfaces of the moving curved edge section. The carousel then passes the pre-heated edge section into contact with an elongated stationary curved forming shoe along the outer edge of the carousel to progressively bend the pre-heated section into a curved wall section of compound radius. The carousel then passes the formed wall section into contact with an elongated stationary curved cooling rail extending around most of the outer edge of the carousel downstream from the forming shoe.

Abstract: A method for the manufacture of intravascular stents of bioresorbable material comprises the following steps:preparing a viscous solution of poly-.beta.-hydroxybutanoic acid as a bioresorbable polymeric material in a solvent,successively coating a male mold core with layers of the polymer solution in several steps by precipitation of the polymeric material by the solvent being evaporated and by the layer previously precipitated being dissolved at least partially for a homogeneous stent blank to build up,drawing the stent blank off the male mold core, andsubsequently treating the stent blank to finish the shaping of the stent.

Abstract: A method of manufacturing a laminated item such as a prosthesis or tissue expander having a flexible, expandable membrane surrounding an interior lumen to enhance the strength and performance of the membrane comprises the steps of applying a first layer of a fluid, resilient, stretchable material to a mandrel; allowing the fluid material to drain off the mandrel in a first flow direction; allowing the fluid material to harden to form a resilient, stretchable first layer on the mandrel; applying a second layer of the fluid material on the first layer; changing the orientation of the mandrel to allow the fluid material to drain off the mandrel in a second flow direction, the second flow direction being at an angle to the first flow direction; and allowing the fluid material to harden to form a resilient, stretchable second layer on the first layer.

Abstract: The use of comminuted, recycled glass powders as a filler in molded plastic parts is disclosed. The recycled glass preferably has rounded edges, which is a distinct advantage over conventional ground glass which has extremely sharp edges. Suitable comminuted glass is free from contaminants such as grinding compounds. The comminuted recycled glass filler can be used with a variety of different thermoplastics commonly used to in injection molding, rotational molding, and blow molding of plastic parts.

Abstract: A method and apparatus for making plastic articles utilizing a plurality of tools, each of which is moved by cams and includes a nitrogen cylinder wherein provision is made for catastrophic overload prevention. For catastrophic overload prevention, one of the cams is supplied by a top plate and held in normal fixed position by a plurality of nitrogen cylinders. Abnormal movement of the top plate is detected and the machine is stopped. For predictive overload protection, a load cell is positioned at the off load position of one of the cams and any excessive load provides a signal for an alarm, interrupting the feeding of plastic charges and stopping the machine.

Abstract: A mailbox combines a box body and a support molded in one piece together with working hardware, such as a handle, a door or a hinge structure for closing and opening the door of the box. The support provides multiple mounting options through a leg with an elongated segment including an expanded foot, that can be embedded in a ground surface. Alternatively, the elongated segment is truncated to expose an open end of a hollow leg. The present invention also provides a process for molding a mailbox box portion and a post portion in one piece, with the box portion including a door, a box body, and a transition sleeve connecting the door to the box body. The sleeve is truncated from the door and the box body to form an open end on the box body, and the door is pivotally mounted at the open end of said box portion.

Abstract: Novel molding compositions consisting essentially of a mixture of a skin-forming component and a foam core-foaming component physically dry-blended together. The skin-forming component comprises two distinct phases blended together, a high zero-shear viscosity material and a low zero-shear viscosity material. The foam core-forming component preferably comprises a foamable polymeric material including a suitable blowing agent. In a preferred embodiment, the three materials are selected from suitable homopolymers and copolymers of ethylene.

Abstract: The present invention provides a method of manufacturing plastic lenses of urethane type resin having no or very little optical strain by the casting polymerization method. In the casting polymerization process, polymerization is effected while a suitable motion, for example, a particular rotative motion, or a motion based on rotation with the rotatable shaft disposedhorizontal is imparted to the shell to change the direction of the gravity acting on any minute portion of a monomer injected into the shell.

Abstract: A rotationally molded container rim and method for fabrication thereof. The inventive method includes rotationally molding a container while at the same time integrally molding a circumferential rim having an enclosed interior void. Molten plastic and unmelted particles flow from a primary portion of the mold through a gap of uniform width into a secondary mold portion to form the rim. During molding, air is vented from the enclosed void to ambient air outside the mold through a vent opening. The vent opening preferably includes a hollow tube. The rotationally molded container rim that is formed according to the inventive method preferably includes walls that form an enclosed polygonal section. The walls enclose the interior void and at least one vent opening leads from the interior of the rim to the outside of the container.

Abstract: The present invention relates to methods and apparatus for forming seamless cylindrical photosensitive elements of uniform thickness on flexible sleeves. The apparatus for forming a seamless cylindrical photosensitive element of uniform thickness on a flexible sleeve, comprises a mandrel, a mandrel support assembly, a calendering assembly, a drive system and at least a heating element. The methods comprise forming seamless cylindrical photosensitive elements of uniform thickness on flexible sleeves from a stream of molten photopolymerizable material, or a solid or molten sheet of photopolymerizable material. The seamless cylindrical photosensitive elements are formed on polyester sleeves for use on a printing cylinder.

Abstract: A molded unit is made using a rotational molding process. In making the molded unit, a tool assembly houses the mold material. A fixture assembly is also contained within the tool assembly. The fixture assembly holds an insert member in place. The insert member becomes an integral part of the molded unit during the rotomolding process. Preferably, the insert member is spaced from the inner walls of the tool assembly in order to permit mold material to flow and solidify in this space. The fixture assembly is removable from the interior of the molded unit through one or more access openings that are formed in the molded unit.

Abstract: An apparatus for forming grooves in the cylindrical surfaces of tubes or rods has a passage through the apparatus with a grooving roller mounted adjacent the passage. The roller has a helically extending ridge formed on its circumference, with the ridge extending into the passage and the roller being mounted for rotation about an axis inclined to the axis of the passage. The angle of inclination of the axis is such that the ridge, where it extends into the passage, runs at right angles to the axis of the passage. The roller is made to rotate about the tube or rod as the tube passes through the apparatus.