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Printing Production Dates on Aluminum Can Bottoms with CIJ Technology
Aluminum cans are fast-moving, reflective and often handled immediately after coding. The bottom surface is a useful location for production dates and batch information because it remains available for inspection without competing with the package graphics. This application shows a continuous inkjet (CIJ) printer creating a compact black code on the recessed bottom of a can.
Why CIJ Is Suitable for Can Coding
CIJ printing is non-contact and can operate at line speed. The message can include dates, lot numbers, shift information and other variable fields. Unlike a label, the code is applied directly to the container and does not add another consumable or application step.

Reach the Recessed Bottom Surface
The bottom of a can is not completely flat. The printhead must be angled and positioned so the ink stream reaches the intended ring or center area without contacting the container. A rigid bracket prevents gradual movement, while stable can handling keeps the target inside the print window.

Select Ink for Fast Drying and Contrast
Bare or coated aluminum should be tested with the chosen ink. The code needs sufficient contrast on the reflective surface and must dry before cans touch guides, belts or packing equipment. If the line has moisture, lubricant or dust, control the surface condition at the print location and confirm adhesion under real production conditions.
Keep the Message Easy to Inspect
Use a character size that remains readable inside the available area. Avoid placing the message across strong curves or embossed features. Operators should check the first can after a product change and then sample the line at a defined interval. A code that is present but smeared or incomplete should be treated as a quality failure.

Daily Production Checklist
- Confirm message content before starting the line.
- Check printhead alignment with the recessed bottom.
- Verify drying time at normal conveyor speed.
- Inspect contrast and character completeness.
- Clean the sensor and printhead according to the maintenance routine.
CIJ technology provides a flexible way to print variable production information on aluminum can bottoms without slowing the packaging process. DAYSJET can test your can sample and recommend the printer, nozzle size, ink and mounting arrangement for your line.