Systems (200) and methods for making different plastic products (202, 204) in a single melting process are provided. A method includes melting a plastic resin in a first extruder (104) to form a melt (106) and transferring at least a portion of the melt to a second extruder (114). Any portion of the melt (106) that is not transferred to the second extruder (114) is formed into a first plastic product (202). Additives (116) are blended with the melt in the second extruder to form a second melt (118), and a second plastic product (204) is formed from the second melt (118).

A layer sequence repeater module for a co-extrusion die includes a cell formed of a plurality of thin annular disks stacked on top of each other in an axial direction of the co-extrusion die. Each disk includes a plurality of openings aligned with openings in the adjacent disks, thus forming multiple inner and outer melt passages. At least one of the layer sequence repeater module includes at least one first cap disk, at least one second cap disk, at least one distribution disk, at least one repeater disk and at least one spreader disk. The layer sequence repeater module may be a separately assembled and individually removable module of the co-extrusion die. Alternatively or additionally, the layer sequence repeater module may be incorporated into a module of the co-extrusion die.

A large concentric co-extrusion die (1) is described having a plurality of annular or conical die mandrel layers (201-205). Each layer is formed between a pair of adjacent annular or conical die mandrels (101-106) defining between them a flow path for molten thermoplastics material from an inlet to an annular extrusion outlet (110) through which a thermoplastics tubular extrusion is formed in use. Extrusion takes place through the multiple annular layer outlets (301-305) to form a multi-layered product. At least one layer (203) of the annular or conical die mandrels has a plurality of molten material inlets arranged around the external circumference of the co-extrusion die with each inlet being connected to a feed channel (403) which has plural bifurcations (403.1, 403.2, 403.3) providing 2.sup.n subsidiary outlet feed channels (503) where n is the number of bifurcations. Each subsidiary outlet feed channel being connected to a corresponding helical outlet channel (703).

A co-extrusion print head has at least one channel, and a set of orifices fluidically connected to the channel, wherein the set of orifices has at least one orifice at each edge of the set has a smaller vertical extent than the other orifices.

A feedblock including a first packet creator that forms a first packet including a first plurality of polymeric layers, the first plurality of layers including at least four first individual polymeric layers; and a second packet creator that forms a second packet including a second plurality of polymeric layers, the second plurality of layers including at least four second individual polymeric layers, wherein the first and second packet creators are configured such that, for each packet creator, respective individual polymeric layers of the plurality of polymeric layers are formed at approximately the same time. The feedblock may include a packet combiner that receives and combines the first and second primary packets to form a multilayer stream. In some examples, at least one of the first and second primary packets may be spread in the cross-web direction prior to being combined with one another.

A scintillator stack includes a light-transportation layer and a scintillator layer. The scintillator stack can be included in a scintillator device. The scintillator stack can be made using a co-extrusion method.

An extrusion device has a stack of at least two layers, the stack including an outlet, an inlet for a first material, and a feed channel for the first material arranged to fluidically connect to the inlet for the first material, the feed channel having a sloped end. A method of manufacturing an extrusion device includes forming an outlet, an inlet for a first material and a feed channel for the first material having a sloped end in a stack of layers, aligning the stack of layers to fluidically connect the feed channel for the first material with the inlet for the first material and to fluidically connect the inlet for the first material with the outlet, and bonding the layers together.

A feedblock including a first packet creator that forms a first packet including a first plurality of polymeric layers, the first plurality of layers including at least four first individual polymeric layers; and a second packet creator that forms a second packet including a second plurality of polymeric layers, the second plurality of layers including at least four second individual polymeric layers, wherein the first and second packet creators are configured such that, for each packet creator, respective individual polymeric layers of the plurality of polymeric layers are formed at approximately the same time. The feedblock may include a packet combiner that receives and combines the first and second primary packets to form a multilayer stream. In some examples, at least one of the first and second primary packets may be spread in the cross-web direction prior to being combined with one another.

A die and a method for impregnating fiber rovings with a polymer resin are disclosed. The die includes a manifold assembly (220), an impregnation zone (250), and a gate passage (270). The manifold assembly (220) flows the resin therethrough, and includes a channel (222). The impregnation zone (250) is in fluid communication with the manifold assembly (220), and is configured to impregnate the roving with the resin. The gate passage (270) is between the manifold assembly (220) and the impregnation zone (250), and flows the resin from the manifold assembly (220) such that the resin coats the roving. The gate passage (270) includes a projection (300). The projection (300) is configured to diffuse resin flowing through the gate passage (270).

A reflective optical film includes a reflective light-polarizing unit including a multilayer reflective sheet composed of a plurality of polymer films stacked on top of one another. Each polymer film has a thickness, every two adjacent polymer films are two different materials, and the thicknesses of the polymer films are gradually decreased from two outmost sides of the multilayer reflective sheet to a middle of the multilayer reflective sheet. At least one of the polymer films is a birefringence material layer that conforms to the condition of NXNYNZ, where NX is the index of refraction of light at X direction of the multilayer reflective sheet, NY is the index of refraction of light at Y direction of the multilayer reflective sheet, and NZ is the index of refraction of light at Z direction of the multilayer reflective sheet.