In cosmetic tube packaging, the eye mark is small yet vital. Hidden from consumers, it enables accurate print registration, sealing timing, and quality control in automated production. Below we present Auber’s insights and best practices to help brands and packaging professionals better value this subtle but strategic feature.
Why Eye Marks Matter & Common Challenges
1 Automated Sealing & Positioning
In high-speed tube finishing lines, the sealing machine needs a precise signal for when and where to heat-seal the tail end of the tube. The eye mark allows the sensor or camera to detect the correct timing and position. If the mark is poorly designed—e.g. too small, too low contrast, or placed in a noisy print area—misdetection occurs, leading to skewed sealing, adhesive overflow, or misaligned seals.
2 Interference from Print Registration Lines
When using 360° full-wrap printing, the “printing combine line” (i.e. where the print edges meet) can contain strong color transitions or graphic elements. Such areas may confuse the detection system. The eye mark may be misinterpreted as the print seam, or vice versa, especially if their contrast or spacing is insufficient.
We have seen instances where a client’s tube artwork had heavy solid-color blocks, making the eye mark indistinguishable or triggering false cues in the detection system.
3 Stability & Consistency Across Runs
Even when a eye mark is properly designed, production variations (e.g. material stretch, web tension, registration drift, vibration, or device fluctuations) can shift its effective position on the tube.
Moreover, different sealing machines or sensors have varied sensitivity to contrast, color tones, and shape. When a customer switches lines or plants, the eye mark’s robustness is often tested in new environments.
Auber’s Suggestions
1. First, clarify the specific requirements of your filling/sealing machine for the eye mark—including size, position, and color contrast—to align with the machine’s detection capabilities. Moreover, take them into consideration when making the designs.
2. During the early artwork design review, place the eye mark in a horizontally clear area (no overlapping colors, patterns, or print elements in the same horizontal zone) to avoid interference from print seams or solid-color blocks.
3. Before mass production, conduct a small-batch filling and sealing test—especially when switching contract manufacturers or production lines—to verify the eye mark’s stability and detection accuracy in the actual production environment.
If your team is reviewing eye mark design, print registration, sensor compatibility, or sealing reliability, reach out to Auber. We’re happy to offer tailored solutions and support.
Further information:
how to seal the tube tail?
//www.cosmetic-tube.com/videos/auber-new-tail-sealing-machine
how to seal the tube tail?
//www.cosmetic-tube.com/videos/auber-new-tail-sealing-machine
