From Pellets to Sheet: Where Every Sushi Box Begins
21 October 20262 min readShenzhen & Shantou, Guangdong
Our own sheet line — pellets in, molten PS through the die, calender rollers, sheet stacked for forming.
Most sushi box conversations start at the forming press. Ours start one step earlier, because the sheet decides almost everything: how clear the box looks, how stiff it feels in the hand, and whether the lid closes the same way on box number one and box number fifty thousand. This video was filmed on our own extrusion line — the step before forming.
Pellets inFood-grade PS resin is loaded into the hoppers and fed to the extruder. Material choice sets clarity, stiffness and food-safety compliance at the source.
Melt and extrudeInside the extruder the pellets melt into a uniform stream, then pass through a flat die as a continuous molten web of plastic.
Calender and coolA stack of polish rollers presses the web to a set thickness — measured in fractions of a millimetre — while it cools and hardens.
Stack for formingThe finished sheet is trimmed and stacked, ready to feed our thermoforming lines that you saw in the last factory tour.
Sheet quality decides box quality. Clarity, stiffness and consistent thickness are locked in here — before the sheet ever reaches a forming tool.
What this means for your order
Thickness is a choice, not an accident. Thicker sheet means stiffer boxes and better stacking strength; thinner sheet means lower unit cost. Because we run our own line, the gauge is set to your product, not to whatever stock a trader has.
Consistency across shipments. Box one and box fifty thousand come from the same recipe and the same roller settings — which is why our lids fit our bases batch after batch.
Our key products are tested by SGS against US FDA 21 CFR 177.1640 and EU Regulation (EC) No 1935/2004 with (EU) No 10/2011. Reports go out with the shipment, not after you chase them.
