Continuous stationery

Continuous stationery (UK) or continuous form paper (USA) is paper which is designed for use with dot-matrix and line printers with appropriate paper-feed mechanisms. Other names for continuous stationery include fan-fold paper, sprocket feed paper, burst paper, tractor-feed paper, and pin feed paper. It can be single-ply (usually woodfree uncoated paper) or multi-ply (either with carbon paper between the paper layers, or multiple layers of carbonless copy paper), often described as multipart stationery or forms.

Most continuous form paper is punched longitudinally along both edges with regularly spaced engagement holes that engage with sprocket wheels or toothed belts which move the paper through the printer. It is usually perforated transversely with a line of closely spaced holes or slits which form a tear edge that allows it to be torn neatly into separate pages after printing; when fed through the printer the paper is simply a continuous sheet.

After printing the separated sheets can be held in binders by using the sprocket holes when simply required as a record. Alternatively some types of continuous form paper also have longitudinal perforations along each edge inside the engagement holes, allowing the strips with sprocket holes to be torn off the printed page, leaving only the printable part.

The tear perforations may be short slits, which leave noticeable serrations when torn apart, acceptable for many business documents such as invoices. Where better appearance is necessary the perforations can be much finer, leaving an almost perfectly smooth edge (microperforations, microperf for short).

Continuous form paper of all types remains in production, although largely supplanted with the introduction of fast laser printers with single-sheet feed. Continuous stationery printed on a suitable printer is typically cheaper than laser printing although the output is of lower quality. If an impact printer is used multiple simultaneous copies can be printed on multipart forms. Many laser printers can print on both sides of the paper (duplex printing), not possible with continuous stationery.

The highest grade of continuous form paper uses a heavy bond weight similar to typing paper. Perforations are very small and close together, referred to as microperforations or microperf, to allow the sheets to be separated and the sprocket hole strip torn off leaving a very smooth edge almost as if guillotine-cut.

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