A co-injection hot runner nozzle comprises an inner melt flow channel and an annular outer melt flow channel that surrounds the inner melt flow channel. The inner and outer melt flow channels have a first common source. The nozzle further comprises an annular intermediate melt flow channel disposed between the inner and outer melt flow channels. The annular intermediate melt flow channel is at least partly defined by a plurality of spiral grooves, each spiral groove having a respective inlet and defining a helical flow path. Lands between adjacent spiral grooves increase in clearance in a downstream direction. An annular axial flow path is defined over the lands. A plurality of feeder channels having a second common source is configured to supply melt to the plurality of inlets of the spiral grooves. The relationship of feeder channels to spiral grooves may be one-to-one. The inlets may be longitudinal channels.

An automotive injection-molded product includes natural pellets and masterbatches that color the natural pellets. In the automotive injection-molded product, a color difference between a high concentration portion and a low concentration portion of the masterbatches with respect to the natural pellets in a flat plate is not more than 6.5.

A co-injection hot runner nozzle comprises an inner melt flow channel and an annular outer melt flow channel that surrounds the inner melt flow channel. The inner and outer melt flow channels have a first common source. The nozzle further comprises an annular intermediate melt flow channel disposed between the inner and outer melt flow channels. The annular intermediate melt flow channel is at least partly defined by a plurality of spiral grooves, each spiral groove having a respective inlet and defining a helical flow path. Lands between adjacent spiral grooves increase in clearance in a downstream direction. An annular axial flow path is defined over the lands. A plurality of feeder channels having a second common source is configured to supply melt to the plurality of inlets of the spiral grooves. The relationship of feeder channels to spiral grooves may be one-to-one. The inlets may be longitudinal channels.

An injection molding apparatus (5) comprising an injection molding machine (15), one or more upstream channels (19bfc, 40dfc) and one or more nozzle channels (42a), wherein a spring, coil, wire, rod or cylinder (800) configured in the form or shape of a spiral or helix is disposed within and extending axially through one or more of the upstream channels and the nozzle channel, the spring, coil, wire, rod or cylinder being adapted to guide flow of injection fluid flowing downstream through the channels in a disrupted or discontinuous manner.

A co-injection nozzle is disclosed that includes a combining means configured to reduce shear heating and create a more even shear heating profile in core and skin material flow streams. The combining means is configured to reduce shear heating peaks and valleys in core and skin material flow streams as the streams flow between annular channels of the combining means during a mold filling process.

A co-injection hot runner nozzle comprises an inner melt flow channel and an annular outer melt flow channel that surrounds the inner melt flow channel. The inner and outer melt flow channels have a first common source. The nozzle further comprises an annular intermediate melt flow channel disposed between the inner and outer melt flow channels. The annular intermediate melt flow channel is at least partly defined by a plurality of spiral grooves, each spiral groove having a respective inlet and defining a helical flow path. Lands between adjacent spiral grooves increase in clearance in a downstream direction. An annular axial flow path is defined over the lands. A plurality of feeder channels having a second common source is configured to supply melt to the plurality of inlets of the spiral grooves. The relationship of feeder channels to spiral grooves may be one-to-one. The inlets may be longitudinal channels.

An injection molding apparatus including an actuator interconnected to a rod or valve pin having a smooth continuous cylindrical outer surface and one or more discontinuous or relieved or relieved portions formed as discontinuities in the cylindrical outer surface and adapted to be disposed within a fluid flow channel, the one or more discontinuous or relieved portions being configured and arranged along the axial length of the pin or rod such that the flow of injection fluid over or past the one or more discontinuous or relieved portions is modified to flow at substantially different rates or velocities or in substantially different flow patterns relative to rate or velocity or pattern of flow of injection fluid over or past the smooth continuous cylindrical outer surface.

Disclosed herein is an injection mold for production of marbled moldings, including at least one hot runner, a cavity, an entry opening into the injection mold and an inlet into the cavity, where the hot runner has at least two ducts that are connected at a first end of each duct to the inlet into the cavity and at a second end of each duct to the entry opening into the injection mold, where the at least two ducts each at least partly form a spiral, and the at least two ducts are bounded by a one-piece component. Further disclosed herein is a process for producing the injection mold and a process for producing marbled moldings.

A co-injection nozzle is disclosed that includes a combining means configured to reduce shear heating and create a more even shear heating profile in core and skin material flow streams. The combining means is configured to reduce shear heating peaks and valleys in core and skin material flow streams as the streams flow between annular channels of the combining means during a mold filling process.

Disclosed herein is an injection mold for production of marbled moldings, including at least one hot runner, a cavity, an entry opening into the injection mold and an inlet into the cavity, where the hot runner has at least two ducts that are connected at a first end of each duct to the inlet into the cavity and at a second end of each duct to the entry opening into the injection mold, where the at least two ducts each at least partly form a spiral, and the at least two ducts are bounded by a one-piece component. Further disclosed herein is a process for producing the injection mold and a process for producing marbled moldings.