Static Build-Up Affects Print Quality – Resolved with Simple Engineering Fix

Background

We upgraded a customer from an ageing Drop-On-Demand printer to an illumex® Eco X2 single-head printer for printing two-line, 2mm high codes (batch number and best before date) directly onto product labels. The upgrade included the use of Perfecta® Limitless+ ink cartridges, meeting the customer's goals of:

• Higher clarity print

• Lower cost per code

• Reduced maintenance requirements

Initial Success

The installation and commissioning went smoothly. The customer was immediately satisfied with the improved print quality and user experience.

Issue Identified

Within days of installation, the customer reported print quality degradation after 300–400 consecutive prints (see Image 1). Cleaning the cartridge with a lint-free cloth restored print quality—but the issue recurred after a few hundred prints.

We investigated further:

• The nozzle plate of the cartridge was examined and dried black ink was clearly visible (Image 2, circled in red).

• This buildup of ink indicated ink blowback—where ink is repelled back onto the nozzles shortly after ejection.

• The root cause was identified as static electricity on the label surface, creating a barrier that disrupted ink trajectory.

On-Site Investigation & Resolution

Upon returning to site, we found a white plastic vinyl surface located directly behind the label substrate (Image 3, red arrow). This plastic piece had been left behind from an old hot foil stamping machine and was:

• Rubbing against the back of each label

• Generating static charge on the print-facing side of the labels

• Causing ink to be deflected or misdirected onto the cartridge nozzles

Corrective Action

The vinyl component was removed from the label applicator. Following this:

• Over 2,000 test prints were conducted

• No print degradation occurred

• Print clarity remained consistent throughout the run

Customer Outcome

The customer confirmed the issue was fully resolved and expressed satisfaction with both the thorough diagnosis and the effective fix provided by illumex.