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An injection molding apparatus for manufacturing hollow objects, such as plastic e.g. multi-layered preforms, comprising an injection mold (1) with a front (2) and a rear side (3), which is composed of a clamp plate (4) on the front side (2), and a hot runner plate (5), where a manifold (6) is mount

An injection molding apparatus for manufacturing hollow objects, such as plastic e.g. multi-layered preforms, comprising an injection mold (1) with a front (2) and a rear side (3), which is composed of a clamp plate (4) on the front side (2), and a hot runner plate (5), where a manifold (6) is mounted in the hot runner plate, between which a set of injection nozzles (7) is arranged, which are each provided with a central supply duct (8), at the free end (9) whereof an injection gate (10) is provided. Said apparatus is remarkable in that said injection gate (10) is closable by means of a locking rod (11), which is movable herein to and fro through a profiled inner part (12) which is received in a holder (13) around which a heating element (14) is provided into which a primary channel (15) opens for supplying the plastic base material to the injection gate (10). Each injection nozzle (7) is directly removable individually from the injection side (16) of the injection mold at the injection side thereof, and a respective secondary channel (17) is provided separately; and method therefor.

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1. Injection molding apparatus for manufacturing multi-layered hollow plastic preforms, comprising an injection mold (1) with a front (2) and a rear side (3), which is composed of a clamping plate (4) on the rear side (3), and a hot runner plate (5), where in the hot runner plate a manifold (6) is m

1. Injection molding apparatus for manufacturing multi-layered hollow plastic preforms, comprising an injection mold (1) with a front (2) and a rear side (3), which is composed of a clamping plate (4) on the rear side (3), and a hot runner plate (5), where in the hot runner plate a manifold (6) is mounted, between which a set of injection molding nozzles (7) is arranged, which are each provided with a substantially centrally arranged supply duct (8), at the free end (9) whereof an injection gate (10) is provided, wherein each said injection nozzle (7) is directly removable individually from the injection side (16) on the front side (2) of the injection mold at the injection side thereof, wherein each said injection nozzle comprises a profiled inner part removable from the injection side (16) on the front side (2), wherein said injection gate (10) is closable by a locking rod (11) movable therein to and fro through the profiled inner part (12) which is received in a holder (13) around which a heating element (14) is provided into which at least one primary duct (15) passes through for supplying primary plastic base material to the injection gate (10) for forming a primary layer, wherein a respective secondary duct (17) is provided separately, wherein each said injection nozzle comprises an inner channel and an outer channel around the inner channel, wherein the inner channel is within the profiled inner part (12) and the outer channel is around the profiled inner part in the nozzle, andwherein said inner part (12) is supported substantially centered in the holder (13) of the injection molding nozzle (7) thereof, and wherein said profiled inner part (12) has a conical end with a decreasing annular slope extending from a downstream to an upstream direction of flow of the plastic base material, andwherein the primary duct (15) supplies material to the outer channel and the secondary duct (17) supplies material to the inner channel proximal the conical end. 2. Injection molding apparatus according to claim 1, wherein inner sides of said inner part (12) of the injection nozzle (7) have a uniform annular profile with a substantially constant slope (a) towards a space in the upstream direction of flow in the injection nozzle, wherein the slope (a) is less than 30°. 3. Injection molding apparatus according to claim 1, wherein said inner part (12) encompasses a plastic sealed closed system with a close fit substantially without tolerance. 4. Injection molding apparatus according to claim 1, wherein said inner part (12) includes a needle guide (18) in which the needle (11) is movable back and forth individually by being guided therein, wherein said needle guide (18) is composed of a ceramic material, wherein a very tight tolerance is provided on the dimensions of the proposed needle guide (18). 5. Injection molding apparatus according to claim 1, wherein the injection mould has 64 to 128 or more injection nozzles (7) all of which are mutually arranged substantially in parallel to the injection side (16) thereof. 6. Method for producing of multi-layered articles via injection molding plastic preforms, respectively containers, by an injection molding apparatus according to claim 1, wherein each injection nozzle (7) is removed from the injection side (16) on the front side (2) of the injection mold (1) at the injection side thereof, wherein the needles locking rods (11) are actuated by being pulled with an access from the outside (19) from a rear side of the mold. 7. Method according to claim 6, wherein during operation the temperatures of the injection nozzles (7) and the manifold (6) are kept at production temperature being substantially constant except with small fluctuations almost negligible, and wherein when not in operation the inner part (12) in the injection nozzles including the needle guide (18) is dismountable from the front (2). 8. Method according to claim 7, wherein the disassembly is carried out by unscrewing a tip (21) and by dismounting the inner part (12) with needle guide (18) from the holder (13). 9. Method according to claim 7, wherein during the disassembly process of the inner part (12), if contamination or narrowing of the primary or secondary ducts (15, 17) occurs herein, the mold is not disassembled from the rear side (3), and only through the front (2) thereof and/or in that parts of the nozzles are cleaned or replaced without disassembling the entire mold from the rear side (3), but only from the front (2) thereof. 10. Method according to claim 6, further comprising forming the multilayered articles by supplying a secondary material to the injection nozzle (7) via the secondary duct (17), wherein the secondary material is selected from the group consisting of a fluid, semi-fluid or viscous material, forming a secondary layer of the multilayered articles in an intermediate phase selected from the group consisting of pastes, adhesives and other substances that possess a liquid phase under normal conditions of pressure and temperature, and that turn into a solid phase by curing, wherein said secondary material can be evenly applied with fairly low amounts of secondary material with formation of a multilayer structure comprising primary layers, which is composed of a primary plastics material, and the secondary layer between the primary layers, wherein said secondary layer is provided as an interlayer and as a barrier layer, and wherein said secondary material is selected from the group consisting of chemical oxygen scavenger material and/or biological oxygen scavenger material. 11. Method according to claim 10, further comprising adding a predetermined amount of additives preliminarily to at least one of the aforementioned materials prior to the curing, wherein said additives are added with a neutralizing effect on undesirable external influences, wherein said additives are dyes with a neutralizing effect on the external influences and/or substances which have an adverse effect on a product to be contained within the multilayered articles, on an undesirable gas formation originating from a degradation of said product. 12. Method according to claim 10, wherein said secondary material is selected from organic scavengers from bio-polymer aggregates which are composed of organisms of cells and/or cell products incorporated in a polymer, wherein a new function of the thus formed polymer product is achieved, wherein one operates below the operating temperature plate working temperature that is taken from the interval whose lower limit is determined at substantially 100° C., substantially under normal pressure conditions, at substantially 1 atmosphere. 13. Method according to claim 12, wherein said cells are selected from the category of cysts, and/or in the phase of the non-active or dormant states. 14. Method according to claim 12, wherein the cells are selected from prokaryotes, bacteria, duration stages or spores of extremophile bacteria, eukaryotes, yeasts, protists, fungi, and combinations thereof. 15. Method according to claim 12, wherein said organisms are selected among the category of the aerobic micro-organisms or in that said cell products are selected among the category of the so-called metabolites, being the molecules that are synthesized by organisms by biochemical pathway. 16. Method according to claim 6, wherein the plastics are selected among the family of polyolefins among the family of polyethylenes or among the family of polypropylenes, or among the family of polyesters and polyethylene terephthalates. 17. Method according to claim 10, wherein manufacturing a multi-layered preform in an injection mold by injection molding, wherein a predetermined amount of the primary plastics material (PM) is injected in a hollow mold space under relatively high pressure p and temperature T, further wherein a predetermined amount of the secondary material (SM) is supplied into the hollow mold space under conditions of pressure and temperature which are lower than said primary injection pressure p and temperature T, wherein the secondary feed channel (17) is connected to the central supply duct (8) in a common injection nozzle (7) which directly leads to a forming die (45) for the manufacture of a preform (46) in the injection point (10) thereof.