Caroll Tape: Definition and Uses in Dot Matrix Printing

The Caroll Strip: Mechanical Continuous Paper Feeding

The term Caroll strip refers to the perforated strip that surrounds a listing, that is, a continuous paper stack folded accordion-style, used for several decades in professional document printing. The regular perforations along each side of the strip allow the paper to be moved by a dot matrix printing machine, whose mechanism relies on sprocket wheels that engage these perforations to pull the paper steadily and in sync with the print head.

Historically, the Caroll strip was the essential standard for computer printing before the widespread adoption of laser and thermal printers. It equipped needle dot matrix printers used to print pay slips, multi-copy invoices with carbon or carbonless paper, accounting reports, and large administrative documents. The very principle of dot matrix printing, which strikes an ink ribbon against the paper via a needle matrix, required reliable mechanical feeding that only a perforated strip could guarantee over long runs without slipping or print misalignment.

Although largely replaced by direct thermal and thermal transfer printing technologies in most common uses, the Caroll strip remains present in certain specific industrial or administrative environments. Some legacy systems, still in operation in government offices, industrial workshops, or applications requiring simultaneous printing of multiple carbon copies, continue to operate on this principle, maintaining a residual but real demand for this type of consumable.

For a professional assessing their printing fleet, distinguishing the Caroll strip from modern thermal rolls is essential to avoid ordering errors. A dot matrix printer equipped with a sprocket mechanism can only operate with perforated paper suited to its feed width, measured between the two rows of perforations, and not with a standard thermal roll, which has no perforations nor compatibility with this type of mechanism.

The gradual shift to direct thermal printing is largely explained by the limitations of the Caroll strip: high operating noise due to mechanical impact, slower printing speed, regular maintenance of needle equipment, and rising costs of these specific consumables compared to the continuously falling price of thermal rolls. Nevertheless, in cases where multiple carbon copies remain a regulatory or practical requirement, such as certain transport or administrative documents needing several simultaneous copies without intermediate electronics, the Caroll strip remains a relevant and sometimes irreplaceable technical solution in the short term.