There are several transitional physical phases which the plastic powdered resin goes through when inside a biaxially rotated mold. To be specific there are four terms assigned to these physical phases; in the following order they are, rotating pool, cascading, rimming and collapsing.
In the rotating pool phase, a majority of the molten resin remains in the state of a liquid pool at the bottom of the mold; this tends to occur when the liquid is a low viscosity and at a low rotation speed.
The cascading flow occurs at higher rotation speeds and viscosity causing the liquid pool to rise and get carried over the top. Eventually cascading to the opposite side of the mold.
As the speed and viscosity increases further the liquid is carried over the top side of the mold without any cascading or dripping as such. It is essentially carried over the top and follows through in a centripetal motion. The liquid is now said to be of a steady state.
Solid body Rotation occurs when the rotation speed and viscosity are high enough such that there is no liquid flow. At this stage there is no longer a liquid pool instead there is a residue coating the inside of the mold.