Remedies for Non-Scannable Bar Codes

The other day I purchased a Holiday Centerpiece for Thanksgiving dinner. The store was real busy. When I finally reached the checkout counter, the bar code would not scan.

Barcodes that have difficulty being scanned are either misprinted, damaged, are on a curved surface, or are covered over by a film or other substrate that affects the light and reflection of the bar code reader.

Picket Fence vs. Ladder Bar Code Orientation

In this case, the UPC bar code was misprinted. The beginning bars printed too dark, and there was not enough white space between the black bars. Typical remedies include reducing the thermal printhead heat or darkness in the printer driver, or tweaking the print speed to see how that affects the darkness. However, in this case, we have the added constraint of dealing with the print orientation on the tag. Barcodes prefer to be printed horizontally, or “picket fence.” This particular tag’s barcode was printed vertically or in a “ladder” direction. So as the tag finished printing, there ended up with extra-dark, or smudged print. This is a classic issue with bar codes printed in this direction. The pic shows the direction the tag was printed in.

Production Constraints and Thermal Transfer Ribbons

There are grades of thermal transfer ribbons that can minimize this, since changing the orientation of the label or tag isn’t always feasible. In this case, the tag is perforated, has a hang tag slot and hole, and with the space constraint, can’t handle a barcode rotated 90 degrees to be printed horizontally. When producing labels and tags on press, there are production concerns that involve tooling decisions, material yields, and machine time. This particular tag was produced the proper way; rotating it for production purposes would not have made sense.

Barcode Thermal Transfer Printing Remedies

By utilizing the proper grade of thermal transfer ribbon, adjusting the printer driver settings, and considering the orientation of the barcodes, misprinted barcodes can be minimized. This will result in scannable barcodes that keep the Holiday queues moving along.