Applications · small, precise cores

Plastic cores for tapes and labels

ROLL Lab · updated 24 October 2026 · sources at the bottom of the page

Where plastic is needed

• Electronics and photovoltaics: tapes and films for cleanrooms, where fibres are banned.
• Technical and medical tapes: precision, cleanliness, sometimes sterilisation.
• Labels for automatic lines: a precise inside diameter for the spindles of label applicators.
• Thermal paper rolls for tills, card terminals, scales and parking meters: small tubes, often with a 12 mm bore, that must turn freely right up to the last receipt.
• Returnable precision rolls: cores reused in internal loops.

For till rolls the size is usually written as width × outside diameter × core, for example 57 × 40 × 12 mm or 80 × 80 × 12 mm. Many of these rolls have a cardboard core. Plastic tubes are chosen when you need burr-free ends, a constant diameter and a tube that does not go oval: injection moulded, it leaves the mould already to size, without the crush cut that can squash the ends.

In consumer adhesive tape the core almost always remains cardboard: it costs little and goes into paper recycling. Plastic is justified only if one of the conditions above applies.

Cardboard or plastic for tapes: the sums

A small cardboard core costs very little and weighs a few grams: in consumer tape no plastic core can compete on price. The sums change when the core comes back (technical rolls rewound in internal loops), when a core defect is expensive (a stopped electronics assembly line) or when the cleanroom rules out fibres. In these cases the price of the core weighs little against the value of the wound tape, and the precision and cleanliness of plastic are worth the difference.

Extrusion or injection moulding

Small cores are made in two ways. Extrusion gives a continuous tube to be cut to length: flexible on lengths, economical at large volumes. Injection moulding gives finished parts with burr-free ends, integrated ribs, notches or flanges, and very tight tolerances, at the price of one mould per size. Moulded cores need no cutting and therefore produce no chips.

Materials

On small cores the radial pressure from tapes is usually moderate and thin walls are enough. Dimensional stability matters more: an out-of-tolerance bore jams the label applicator or makes the roll slip.

Tolerances and cutting

For 1" to 3" cores, ISO 13542 gives inside diameter tolerances from +0.5 mm (up to Ø 60) to +1.2 mm (Ø 76). With plastic cores, especially moulded ones, tighter values are often requested. With extruded cores, cutting decides edge quality: for rigid ABS and PS a fine saw or a lathe works best, with deburring for clean areas. Cutting · Sizes and tolerances.

Try it with your own data below; method, assumptions and sources are on the dedicated page: the plastic core weight calculator.

Why precision matters

On automatic label applicators the label roll goes onto a spindle with little play and unwinds at high speed with frequent stops. A bore that is too large makes the roll slip and shifts label placement; too small, and the roll will not go on. In technical tapes for electronics, the roll is unwound by application machines that need well-centred rolls. In these cases the core tolerance becomes part of the quality of the finished product.

A sample specification

ROLL Lab illustrative example.

Reuse in internal loops

Many technical tape makers wind log rolls on large cores and then slit onto small ones. Log roll cores often stay in-house and lend themselves to reuse: they come back from slitting, are checked and go out again. Small cores, on the other hand, leave with the product and rarely return. That is why, in the same plant, it can make sense to use plastic for log roll cores and cardboard for finished roll cores. Reuse and return loops.

End of life

Small plastic cores often reach the end user together with the tape or labels. Under EPR rules they are packaging (in Italy, for example, a tube that reaches the end user without further processing is subject to the CONAI fee), and in the UK they count as plastic packaging components for the Plastic Packaging Tax. For recycling, mark the polymer on the core (for example “>PS<” or “>ABS<” to ISO 11469): these materials have smaller recycling chains and need to be identified. Recycling.

Frequently asked questions

Further reading

Sources

1. ISO 13542:2006 (inside diameter tolerances)
2. ISO 11469 (marking of plastic products)
3. CONAI circular of 27/06/2013 on tubes and rolls (Italy)
4. ROLL Lab analysis