Date and Batch Code Printing on Caps, Pouches and Bags

Dates, batch numbers and product information must remain readable on many different packages. These application examples show continuous inkjet printing on a plastic bottle cap, a small foil pouch, a large plastic bag and card-shaped packaging moving on a conveyor.

One coding method for different package shapes

Continuous inkjet printing is suitable for many production lines because the printhead does not touch the package. It can print on flat, curved and moving surfaces when the product is guided past the printhead at a controlled distance.

The yellow plastic cap shows a clear date and Chinese characters. The foil pouch demonstrates printing on a flexible package. The large plastic bag carries several lines of product and production information, while the card-shaped package shows how multiple lines can be printed on individual items.

Common information printed on packaging

• Production and expiry dates
• Batch and lot numbers
• Factory, shift or workshop codes
• Product specifications and internal tracking information
• One-line or multi-line text

Conveyor integration

The conveyor keeps the package moving in a predictable direction. A sensor detects each product and sends a print signal to the printer. The printhead position, sensor distance and message delay are adjusted so the code appears in the required area.

Flexible pouches and bags may move or wrinkle during transport, so guides and stable spacing are important. Caps and other round products also need consistent orientation if the code must appear in a fixed position.

Selecting the ink

Ink selection depends on the package material, color, surface treatment and required resistance. Before production, the factory should test adhesion, drying time and code clarity on the actual package. This avoids choosing an ink based only on the material name.

DAYSJET can test customer samples and recommend a practical printer and ink combination for bottle caps, pouches, plastic bags and other packaging products.

Application photos

The screenshots below show the printed bottle cap, foil pouch, multi-line plastic bag and card-shaped packages.