The production process of disposable paper tableware (such as paper cups, paper bowls, and paper plates) is a highly automated and continuous industrial procedure, with the two core steps being "base paper coating" and "molding.".
Here is the detailed breakdown of the production process:
Step 1: Raw Material Preparation - Base Paper and Lamination
This serves as the foundation for all paper tableware. The material used is not ordinary paper but food-grade base paper, which must undergo a crucial process—laminating.
The base paper itself is neither waterproof nor oil-resistant.
The large rolls of raw paper are fed into the machine, where a high-temperature extrusion device applies a thin layer of polyethylene (PE) plastic film or polylactic acid (PLA) bioplastic film to one or both sides of the paper.
PE Lamination: The most common type, with low cost and good performance, but it is non-degradable.
PLA Lamination Film: Made from renewable resources such as corn starch, it is compostable and more environmentally friendly, but requires stricter production and usage conditions.
The paper after lamination becomes "laminated paper," which is the direct raw material for producing paper tableware.
Step 2: Printing (Optional)
If the tableware requires patterns or logos, they will be printed on the paper after the lamination process.
Process: Typically, flexographic printing is used, which employs environmentally friendly water-based inks and is more suitable for food packaging. (Some also choose offset printing)
Sequence: Some processes opt for printing before lamination (reverse printing), while others choose printing after lamination (front printing). Printing after lamination is more common, as the smooth surface of the PE film yields better printing results.
Step 3: Molding
This is the core step in transforming flat laminated paper into three-dimensional tableware.
Feeding: The printed and laminated paper roll is fed into the molding machine. The machine first cuts the paper roll into rectangular sheets of specified dimensions.
Heating: The sheet material is conveyed to a heating station for preheating, which slightly softens the PE lamination layer, enhancing plasticity and facilitating forming.
Stamping:
The preheated sheet material is fed into a mold with a specific tableware shape, such as cup or bowl.
The mold is divided into the upper mold (male mold) and the lower mold (female mold).
Under high pressure, the upper die descends and stamps the sheet material, forcing it into the lower die to achieve instant forming.
Trimming: During the stamping process, the sharp cutting edge of the mold removes excess burrs and scraps. These scraps are collected, recycled into pulp, and reused.
Step 4: Subsequent Processing and Packaging
Bottom bonding (for paper cups):
The body and bottom of a paper cup are formed separately. At another workstation, the machine will automatically feed the prefabricated circular cup bottom and bond it with the cup body through hot pressing to ensure a leak proof seal.
Disinfection and quality inspection:
The formed tableware will undergo surface sterilization and disinfection through ultraviolet irradiation or other methods.
At the same time, there will be automatic optical inspection systems or manual sampling to check whether the product is damaged, deformed, stained, or has printing defects.
Packing:
Qualified tableware is counted by automated machines and packaged into a certain quantity (such as 50 pieces per pack) using plastic film.
Finally packed into cardboard boxes and stored for shipment.
Summary flowchart
Food grade raw paper → Film coating (covered with PE or PLA) → (printing pattern) → Die cutting and feeding → High pressure compression molding&edge rolling&cutting → (bottom bonding) → Disinfection and quality inspection → Counting and packaging → Finished product storage