Abstract: A glass facer for a constructions board includes a first non-woven layer of coarse fibers and a second non-woven layer of coarse fibers and microfibers. The glass facer also includes a binder that simultaneously binds or adheres the coarse fibers of the first non-woven layer together, the coarse fibers and the microfibers of the second non-woven layer together, and the first non-woven layer to the second non-woven layer. The first non-woven layer has a porosity and air permeability that enables the first non-woven layer to absorb a material of the construction board when the glass facer is positioned atop the construction board during manufacture of the construction board. The second non-woven layer is configured to block the material of the construction board from passing through the glass facer to an exterior surface of the second non-woven layer so that the material is not externally visible.

Abstract: The invention relates to a multi-layered body comprising a transparent thermoplastic layer, a diffuser layer and a metal layer which, despite a decorative, structured visible surface, can transport information from a projection unit behind it with excellent sharpness and brightness. Corresponding elements can be used, for example, in Car-to-X communication.

Abstract: A system for transporting and installing a cured-in-place-pipe (CIPP) liner to line existing pipe includes a chassis, a bed supported by the chassis and wheels mounted on the chassis for supporting the chassis as it is moved over the road. A container supported by the chassis has a first compartment and a second compartment. A refrigeration system supported by the chassis is operable to keep the first compartment cooled to a temperature at which resin carried within the liner does not prematurely cure. The second compartment contains a powered feeder that can pull liner from the first compartment through a port and feed it out of the container for installation. A method is also disclosed.

Abstract: A method for producing injection-molded parts by a two-component injection-molding technique in which a first material component is injected into a mold cavity and is displaced into peripheral regions of the mold cavity by injecting a second material component. The first material component is injected into a partial region of the mold cavity at a first gating point and the second material component is injected into the mold cavity at a second gating point and, as a result, the first material component is acted upon by the second material component and displaced in the direction of the regions of the mold to be filled with the first material component. The first material component is thereby displaced into regions of the mold at the wall, and the second material component is introduced in those regions of the mold as a core material and completely into other regions of the mold.

Abstract: Devices, systems, and methods of improving heat transfer between a composite wind turbine blade surface are provided to reduce cure time. The assembly includes molds having heating wires disposed proximate the mold surface for delivering heat to the composite blade during layup and/or resin cure. Additionally, the vacuum bag disposed on top of the composite part includes a plurality of fluid channels for distributing a thermal fluid (e.g. heated/cooled water, air or oil) across the composite surface (opposite the mold surface).

Abstract: The present invention discloses a PET-coated wire for a hanger wherein the wire is coated with PET to form a PET coating having a thickness of 0.03 to 0.05 mm, and a hanger made of the wire. The PET coating apparatus for a wire used for a hanger of the present invention comprises a preheating device 20 for preheating the cleaned wire 10 to 220 to 250° C., an extruder 30 and a dice 40 for coating the preheated wire 10 with PET to form a PET coating having a thickness of 0.03 to 0.05 mm, a cooling bath 50 for cooling the PET-coated wire 100, and a winding device 60 for drawing out and winding the cooled wire. The cooling bath 50 of the present invention is designed such that the wire passes through the cooling bath 50 having a length of 5 m three times for sufficient cooling when the wire proceeds at a high speed of 220 to 300 m/min.

Abstract: A production method for a fiber-reinforced thermoplastic resin composite material, the method using a crosshead die (1) that has a maximum aperture height of 1 mm or more, wherein reinforcing fibers are supplied in a reinforcing fiber bundle to the crosshead die (1), the reinforcing fibers are conjugated with a melted thermoplastic resin, and the conjugate is brought into contact with a pressurization surface that is at or below the solidification temperature of the thermoplastic resin, is pressurized, and is shaped to have a thickness that is 50% or less of the aperture height.

Abstract: Molded polymer foam articles are described as having a novel a foam structure. The polymer foam articles include a continuous polymer matrix defining a plurality of pneumatoceles therein which is present throughout the entirety of the article, including in the surface region extending 500 microns beneath the surface of the article. The surface region is further characterized as having compressed pneumatoceles. The novel foam structure is achieved even when molding polymer foam articles comprising a thickness of more than 2 cm, a volume of more than 1000 cm3; or both a volume of more than 1000 cm3 and a thickness of more than 2 cm. Methods of making the molded polymer foam articles are also described.

Abstract: An object of the present invention is to provide a resin composition for an odor-adsorbing molded article that is excellent in manufacturability, eliminates odor by exerting a high adsorbing effect on odorous organic matter originally contained in packaging materials and odor generated by the decomposition, etc. of resins constituting packages during disinfection/sterilization treatment such as UV irradiation, hot packing, boiling, ? ray irradiation, or EB irradiation, is less likely to desorb the odor once adsorbed and capable of efficiently adsorbing odor and therefore exerts a high adsorbing effect over a long period without reducing the ability to adsorb odor, and is excellent in resistance to change in taste and odor of contents, and an odor-adsorbing molded article prepared from the resin composition for an odor-adsorbing molded article.

Abstract: A bonded joint for use in bonding composite materials is provided and includes a composite rib having electrically conductive properties and a composite structure having electrically conductive properties. An electrically conductive preform is provided that facilitates a bond between the composite rib and the composite structure. A mesh composition that bonds the composite rib to the preform and that bonds the preform to the composite structure is provided and is electrically conductive to conduct current between the composite rib and the composite structure.

Abstract: The invention relates to a method for manufacturing a composite aircraft window frame; the method comprises the steps of: a) positioning in a mold a preform made of pre-impregnated material including dispersed fibers, with a predefined orientation, in a thermosetting resin matrix; b) closing the mold so as to define a gap between at least one surface of said preform and a portion of said mold; c) injecting thermosetting resin into the closed mold through an inlet opening of the mold itself, so as to fill the gap and completely lap said surface of the preform; and d) applying a uniform hydrostatic pressure on the surface by the injection of the resin.

Abstract: A method for impregnating a fibrous preform by injection or infusion, comprising steps of: —providing a mold having at least two portions, said mold presenting an inlet orifice and a vent orifice placed on opposite sides of the mold; —placing a fibrous preform in a portion of the mold; —placing a thermo-expandable seal in a passage formed between an inside wall of the mold and the fibrous preform, said passage extending substantially along the direction (X) extending between the opposite sides of the mold; —closing the mold; —heating the mold so that the thermo-expandable seal expands and shuts off said passage; and—impregnating the fibrous preform with an impregnation material.

Abstract: Methods for forming 3-dimensional eyelashes are provided. One of the methods includes obtaining existing eyelashes made from human hair, animal hair, or artificial materials, applying material to the existing eyelashes to achieve a desired thickness, and sculpting the material to a desired shape of the 3-dimensional eyelashes.

Abstract: Systems, devices, and methods for fabricating finished parts include a system that includes a plurality of die assemblies located at a plurality of respective locations, each die assembly being configured to fabricate a respective finished part. The system further includes a movable gantry press and a robot, each configured to move between the plurality of respective locations. The system further includes a controller configured to receive a input to fabricate a finished part and identify a die assembly of the plurality of die assemblies. The controller is further configured to instruct the movable gantry press and the robot to move to the location of the die assembly. The controller is further configured to instruct the robot to load a blank into the die assembly, and instruct the movable gantry press to operate the die assembly to fabricate the finished part.

Abstract: Methods and apparatus for curing curved cylinder-like workpieces (e.g., in the shape of a half or full barrel) made of composite material, such as nacelle honeycomb core composite sandwich structures. These methods enable tailored curing of composite nacelle structures, to significantly reduce capital cost and fabrication cycle time. In lieu of an autoclave or oven, a pressurized ring-shaped cure volume is defined by a partitioned enclosure that mimics the cylinder-like shape of the composite nacelle structure with only limited clearance (e.g., a partitioned enclosure comprising inner and outer concentric cylinder-like walls). A tool (e.g., a mandrel) and at least one composite nacelle structure supported thereon are placed in the cure volume for curing. Integrally heated tooling, optionally in combination with other heating methods, such as infrared heaters, is utilized to provide the temperature profile necessary for cure.

Abstract: Systems and methods are described where a volume receiving a liquid matrix and fibers at an inlet where opposing sides of the volume converge to form a gap and a moving surface in contact with the liquid matrix and the fibers and moving with respect to the liquid matrix and the fibers through the gap such that shear force is transferred to the liquid matrix and the fibers pushing the liquid matrix and the fibers forward through the gap, creating currents in the liquid matrix and increasing pressure. The increased pressure within the volume forms a barrier to entrained gases within the liquid matrix such that the entrained gases are inhibited from passing through the gap along with the liquid matrix and the fibers.

Abstract: A method, apparatus, and system for managing a composite part. An acceptable level of a warpage is identified for the composite part. The warpage for the composite part is a change in the composite part as manufactured that deviates from design specifications for the composite part. Orientations in a stacking sequence for plies in the composite part are selected that result in the composite part having the acceptable level of the warpage and a desired strength to form selected orientations. The composite part is manufactured using the selected orientations.

Abstract: The invention relates to a method for producing fiber-reinforced composite parts by means of vacuum infusion of a reactive resin mixture, characterized in that the steps of production of the reactive resin mixture and injection into the cavity are carried out in an infusion device in immediate temporal succession.

Abstract: A solid nano- or micro-structured thermoplastic foil including a nano- or micro-structured surface area is produced by providing an extrusion casting roller for an industrial polymer extrusion casting process using a thermoplastic material, applying a nano- or micro-structured surface on the extrusion casting roller, maintaining a temperature of the casting roller below a solidification temperature of the thermoplastic material while the casting roller and the counter roller are rotating, and continuously applying a melt of the thermoplastic material between a counter roller and the casting roller while the casting roller and the counter roller are rotating. A rotational velocity of the casting roller may be 10 meters/minute. The melt of the thermoplastic material is moved between the casting roller and the counter roller while the rollers are rolling, and the melt of the thermoplastic material is solidified upon contact with the casting roller to form the thermoplastic foil.

Abstract: Modular tool inserts for composite part manufacturing and related methods are described herein. An example method includes disposing a preform and a diaphragm assembly above a tool housing and disposing the diaphragm assembly on an upper perimeter surface of the tool housing that defines a cavity. The tool housing includes a docking station and a modular tool insert removably coupled to the docking station. The modular tool insert includes a mold disposed within the cavity. The method includes applying a vacuum within the cavity that pulls the diaphragm assembly, along with the preform, into the cavity such that the preform conforms to a shape of the mold. The method includes removing excess portions of the diaphragm assembly from around the modular tool insert and removing the modular tool insert, along with the diaphragm assembly and the preform, from the docking station.

Abstract: The invention enhances the production efficiency in the production of prepreg by allowing the arrangement property and rectilinearity of reinforcing fibers to be well maintained, allowing the basis weight uniformity of an applied resin to be good, and further allowing a high line speed and suppression of contamination in the process to be achieved. The invention provides a method of producing a prepreg, which includes: discharging a molten resin from a discharge portion; introducing the discharged resin by an air flow; and capturing the discharged resin on a reinforcing fiber sheet conveyed continuously, wherein a key point is that the discharged resin is captured in a region in which the reinforcing fiber sheet is conveyed substantially in planar form.

Abstract: A method includes: (a.) providing a fabric comprising a first surface and a second surface; (b.) placing the fabric on a support structure adapted to permit gas circulation through at least a portion of a surface of the support structure, wherein the fabric is placed such that the first surface of the fabric faces the surface of the support structure and such that the fabric is arranged at least in part over a raised or embossed portion of the support structure; (c.) providing at least one coating comprising a first coating surface and a second coating surface opposite the first coating surface; (d.) placing the coating at least partially on the second surface of the fabric, such that the first coating surface faces the fabric; and (e.) applying a gas pressure differential between the second coating surface and the first surface of the fabric.

Abstract: A additive manufacturing system includes a containment housing operable to form a containment chamber with a low pressure operating atmosphere and an additive manufacturing build housing within said containment housing.

Abstract: In one embodiment, a stiffener may be formed by inserting a plurality of flexible mandrels into a channel of a tool having a three-dimensional contour, placing a vacuum bag over the flexible mandrels and the tool, with the mandrels disposed between the vacuum bag and the tool, and applying vacuum pressure between the vacuum bag and the tool. A hardening substance may be inserted into each of the plurality of flexible mandrels and then may be hardened while the plurality of mandrels are inserted in the one or more channels of the tool. Finally, the mandrels may be wrapped with a stiffener material with stiffeners being formed from the stiffener material.

Abstract: An apparatus for forming blanks from fibrous material is disclosed. The apparatus includes a die having a porous body with a plurality of perforations extending there through, the plurality of perforations having varying sizes and being layered from a top surface to a bottom surface of the porous body. A smooth molding surface is provided on the top surface to hold the fibrous material and allow water to drain from the fibrous material through the plurality of perforations.

Abstract: The present disclosure provides three-dimensional (3D) printing processes, apparatuses, software, and systems for the production of at least one desired 3D object. The 3D printer system (e.g., comprising a processing chamber, build module, or an unpacking station) described herein may retain a desired (e.g., inert) atmosphere around the material bed and/or 3D object at multiple 3D printing stages. The 3D printer described herein comprises one or more build modules that may have a controller separate from the controller of the processing chamber. The 3D printer described herein comprises a platform that may be automatically constructed. The invention(s) described herein may allow the 3D printing process to occur for a long time without operator intervention and/or down time.

Abstract: Systems and methods for drape forming a charge of composite material are disclosed herein. The systems include a forming mandrel, a charge support structure, a flexible and resilient forming membrane, a base, and a vacuum source. The charge support structure includes a flexible and resilient charge support membrane, a membrane suspension device, and a release structure. The release structure operatively couples the charge support membrane to the membrane suspension device when a tension on a peripheral region of the charge support membrane is less than a threshold tension and releases the charge support membrane from the membrane suspension device when the tension is greater than the threshold tension. Alternatively, and in place of the charge support structure, the systems include a means for supporting the charge of composite material. The methods include methods of drape forming a charge of composite material.

Abstract: An RTM molding device and an RTM molding method which enable resin impregnation of even large members and thick members without causing non-impregnated regions or fiber wrinkle, and yield a molded body having superior toughness and excellent precision. In the RTM molding device, a surface molding layer, which is disposed between a fiber-reinforced base material and a molding die, has a plurality of through-holes formed therein, and has sufficient rigidity that the thickness does not substantially change under the pressure inside the cavity when the inside of the cavity is placed under reduced pressure, and a resin diffusion portion, which is located on the side of the surface molding layer opposite the fiber-reinforced base material, and comprises a resin flow path formed so as to connect with the plurality of through-holes of the surface molding layer, are provided on at least one surface of the fiber-reinforced base material.

Abstract: An extruded air cooled blown film having a) a total thickness of 5 to 500 ?m, b) a mono-layer structure or 2 to 9 coextruded layers, c) at least one layer L containing a polymer selected from the group consisting of polypropylene homopolymers, polypropylene random copolymers, hetero-phasic polypropylene block copolymers, or any mixtures thereof, said polymer having a melt flow rate, according to ASTM D-1238, of 0.1 to 10 dg/min at 230° C. and 2.16 kg, said layer L further containing 0.001 to 2%, relative to the weight of the polymer, of a particular nucleating agent, and optionally d) a Modulus according to EN ISO 527 enhanced by at least 10% versus a reference film without the nucleating agent.

Abstract: The invention refers to a method for forming an article having a decorative surface comprising: a) screen printing an ink composition comprising a curable composition onto at least one major surface of a thermoformable polymeric sheet; b) curing said curable composition to obtain a printed sheet having on at least one major surface an ink comprising a cured composition; and c) thermoforming the printed sheet to obtain a decorated article, wherein said curable composition comprises a polyisocyanate and a component comprising isocyanate reactive groups and wherein said ink composition contains a solvent or solvent blend in which said curable composition is soluble or miscible.

Abstract: A spot repair method of scratch-resistant paint film: (a) sanding a part to be repaired having a scratch-resistant clear paint film thereon, (b) sanding a part to be clear gradation painted outside the part to be repaired with an abrasive material, (c) painting the part to be repaired with a color base-paint, (d) applying a clear paint wet-on-wet without curing the color base-paint, (e) applying a clear paint diluted with a gradation agent to the part to be gradation painted, (f) drying the applied paints, and (g) polishing the dried parts, wherein (1) the clear paint is a two-liquid type having an isocyanate curing agent and (2) the gradation agent comprises from 5 to 50 mass % ethyl ethoxypropionate, from 1 to 5 mass % of an acrylic resin as solid fraction, a surfactant and a curing catalyst.

Abstract: An apparatus for laminating substrates includes a laminating fixture having an open-topped recessed space formed by a pair of corresponding sidewalls for holding a target substrate therein. The recessed space is communicable with an air evacuation passage. A supporting structure is formed in the recessed space for supporting two opposite ends of a flexible substrate thereon, such that a bottom of the flexible substrate is spaced from a laminating surface of the target substrate by a predetermined distance. A soft plate is disposed over the open-topped laminating fixture to form an airtight chamber in the laminating fixture. When the airtight chamber is vacuumed using a vacuum pump via the evacuation passage, the soft plate is subjected to a suction pressure and downward deformed to press the flexible substrate downward, causing the flexible substrate to deflect to attach its bottom on the laminating surface of the target substrate.

Abstract: An aspect of the present invention is a method for producing a resin film, including a casting step of casting a resin solution containing a transparent resin from a casting die onto a running support to form a cast membrane, and a releasing step of releasing the cast membrane from the support, wherein, in the casting step, a velocity at which the resin solution is discharged from longitudinally opposite ends of a discharge port of the casting die is 0.95 times to 1.5 times a velocity at which the resin solution is discharged from a longitudinally central portion of the discharge port of the casting die.

Abstract: A method for producing a plastic article includes extruding an approximately tubular blank from an extrudate and shaping the blank into a hollow body inside a blow-mold using differential pressure, wherein at least one insertable part is introduced into the interior of the partially molded plastic article before the latter is fully shaped into a finished plastic article, and the tubular blank is arranged between at least two halves of a blow-mold by means of an intermediate frame.

Abstract: A unitized composite structure comprises a composite member having at least one integrally formed composite stiffener. At least one end of the stiffener includes a runout forming a substantially smooth transition between the stiffener and the composite structure.

Abstract: A method of producing a panel includes: placing an assembly including core elements and impregnatable material webs extending along and between the core elements on a mold, which assembly includes a first side and a second side which is situated opposite the first side, enclosing the assembly under a cover layer in a sealing manner with respect to the mold, introducing at least one inlet for injection material, which inlet ends at a first side of the assembly, connecting the space which is enclosed by the cover layer and the mold to a discharge, injecting injection material via the inlet on the first side of the assembly and causing the injection material to move along via paths formed by the material webs between the core elements, discharging air and/or gas from the enclosed space via the discharge via underpressure at a position which is at a different level to the position where the inlet ends.

Abstract: An epoxy resin composition for RTM molding of a fiber-reinforced composite material includes [A] to [D] below, wherein [A]/[B], which is a blend mass ratio of [A] to [B], is in the range of 55/45 to 95/5: [A] a multifunctional epoxy resin that is liquid at normal temperature or has a softening point of 65° C. or lower, the multifunctional epoxy resin being at least one selected from phenol novolac epoxy resin, cresol novolac epoxy resin, and triphenylmethane epoxy resin; [B] an alicyclic epoxy resin; [C] an acid anhydride curing agent; and [D] a curing accelerator.

Abstract: A method and apparatus for compacting composite stringers. In one illustrative embodiment, an apparatus comprises a compacting structure, a compactor vacuum system, and a carrier vacuum system. The compacting structure has a shape configured to contact layers of uncured composite material for a composite stringer. The compactor vacuum system is associated with the compacting structure. The compactor vacuum system is configured to cause the compacting structure to apply a pressure to the layers of uncured composite material when a compactor vacuum is applied to the compactor vacuum system. The carrier vacuum system is associated with the compacting structure. The carrier vacuum system is configured to hold the layers of uncured composite material against the compacting structure when a carrier vacuum is applied to the carrier vacuum system.

Abstract: A molding die is mainly constituted of a die surface shell layer (15) having a die surface (32) responsive to the shape of a composite item and a support (16) supporting the die surface shell layer (15). The die surface shell layer (15) is made of a material having air permeability, and a prepreg material (34) is placed on a die-shaped surface (32) thereof. Then, the prepreg material (34) is covered with a nonpermeable vacuum bag film (35), and a cavity portion (30) of the support (16) is evacuated. The die surface shell layer (15) has air permeability, whereby it follows that air present on the die-shaped surface (32) is also discharged into the cavity portion (30) through the die surface shell layer (15). Consequently, the prepreg material (34) is pressed against the die-shaped surface (32) by the atmospheric pressure outside the vacuum bag film (35), and strongly adheres.

Abstract: A method of forming a container includes providing a preform of the container. The preform has a wall with an interior region and an exterior region. The method also includes disposing the preform in a mold cavity wherein the mold cavity has a mold surface. Furthermore, the method includes introducing a substance into the preform to expand the preform toward the mold surface. The interior region of the wall has a first interior temperature prior to the introduction of the substance and a second interior temperature after the introduction of the substance. The exterior region of the wall has a first exterior temperature prior to the introduction of the substance and a second exterior temperature after the introduction of the substance. The method further includes controlling the first interior temperature to be greater than the first exterior temperature prior to the introduction of the substance.

Abstract: Injection stretch blow molded (ISBM) articles containing a bio-based polymers and methods of forming the same are described herein. The method generally includes providing a propylene-based polymer; contacting the propylene-based polymer with polylactic acid to form a polymeric blend; injection molding the blend into a preform; and stretch-blowing the preform into an article.

Abstract: A door including a decorative panel is provided. The door may include a door liner, an outer door connected to the door liner, an insulation material disposed between the door liner and the outer door, and a decorative panel provided on an outer surface of the outer door. The decorative panel may include a front surface and a side surface extending at a bend from the front surface. The door may be coupled to a refrigerator or other home appliance.

Abstract: A process for producing a hollow profiled component formed by joining at least two laminated component elements, includes the steps of laminating a first of the component elements with at least one indentation, arranging a preformed hollow body in the indentation, applying an adhesive agent to a surface area of the first component element next to the indentation, placing the first component element together with the hollow body on the second component element with the indentation facing the second component element and the surface area provided with the adhesive agent contacting the second component element, covering the two component elements with a non-rigid fluid-tight covering, the interior of the hollow body being sealed off from the interior of the covering and being fluidically connected with the ambient exterior environment, placing the covered component elements in a pressure chamber, and applying a vacuum to the interior of the covering.

Abstract: A process for the production of a stiffened panel made of composite material, includes the stages of depositing the fibers that constitute the panel on a rigid device (50), depositing the at least one stiffener (14), covering the unit with a sealed wall connected to the rigid device (50) on the periphery of the panel, and then polymerizing, and providing—for each stiffener (14)—a rigid counter-mold in contact with the convex surface of the stiffener (14), using—for each stiffener (14)—a core (66) in the form of a flexible and sealed bladder, and subjecting the interior of the bladder to pressure during polymerization for compacting the stiffener (14) and the panel.

Abstract: A breather for use in vacuum bag processing a composite part comprises a sheet of permeable material having at least one slit therein.

Abstract: Provided herein are methods for processing electrochemically active materials and resulting active material structures for use in rechargeable batteries. The resulting active materials structures include carbon containing coatings that partially or completely cover the surface of the active material structures. In a typical embodiment, the method includes providing a solution of carbon containing precursor in a solvent, dispersing electrochemically active material in the solution to form a mixture, removing the solvent from the mixture to form electrochemically active material coated with the carbon containing precursor, and heating the electrochemically active material coated with the carbon containing precursor in an inert atmosphere at a temperature sufficient to at least partially convert the carbon containing precursor into a carbon coating.

Abstract: A pressure bulkhead made of fiber composite material for an aircraft fuselage for the pressure-tight axial closure of a fuselage region configured to be put under internal pressure. The bulkhead comprises a first area element, at least one second area element and a plurality of core elements. The first area element has a plurality of receptacles. Each receptacle is configured to receive a core element. The core elements are received in the receptacles between surfaces facing one another of the first area element and of the at least one second area element. The surfaces facing one another of the first area element and of the at least one second area element are connected to one another in regions without core elements.

Abstract: A film containing an interpolymer of ethylene and a 3-substituted C4-10 alkene is prepared using a catalyst system comprising a Ziegler Natta or chromium oxide catalyst.

Abstract: Prepregs and stacks of prepregs based on reactive epoxy resins that can be cured at lower externally applied temperatures such as from 70° C. to 110° C. with acceptably short cycle times comprise epoxy resins of epoxy equivalent weight from 200 to 500 containing a curing agent but no hardener.

Abstract: A hollow plastic body comprises a material composite consisting of a stamp-formed panel or sheet-like first layer of a first thermoplastic synthetic material, an optionally stamp-formed panel or sheet-like second layer of a second synthetic material, and an open-cell or mixed-cell foam layer of a third synthetic material disposed between the first and the second layer. The foam layer may be compressed at least in some sections in accordance with the stamped form of the first layer and/or the second layer. The foam layer may be in mechanical contact with the first or/and second layer substantially only in the compressed sections. Advantageous manufacturing methods for hollow plastic bodies are further disclosed.