Adhesive Tape Spec Unit Converter

Peel adhesion units

Peel adhesion is a force per unit of tape width. US datasheets usually give it in ounces per inch (oz/in) or pounds per inch width (piw, lb/in); European and Asian datasheets use newtons per 25 mm (N/25 mm) or newtons per centimetre (N/cm). Older and some Asian datasheets use grams-force or kilograms-force per 25 mm.

Tensile strength of tape backings is reported in the same force-per-width units, so the same converter works for it.

Why converted peel values still may not match

A unit conversion makes two numbers comparable in scale, not in test conditions. Peel results depend heavily on how the test was run, so check the method before comparing two tapes.

• Test method: ASTM D3330, PSTC-101 and ISO 29862 (which replaced EN 1939) all describe peel tests, with different options.
• Peel angle: 180° and 90° peel give different values for the same tape.
• Dwell time: a value measured 1 minute after application can be much lower than one measured after 20 minutes or 72 hours.
• Test surface: stainless steel is the usual reference; values on polypropylene, polyethylene or painted parts can be far lower.
• Peel speed and temperature: most tests use about 300 mm/min at room temperature; other speeds change the result.

Thickness: mils and microns

One mil is one thousandth of an inch, or exactly 25.4 µm. Tape thickness on US datasheets is usually in mils; elsewhere in mm or µm. Check whether a datasheet quotes the thickness with or without the release liner — the liner can be thicker than the adhesive.

Bond strength, coat weight and foam density

Bond strength (for example dynamic tensile or normal tensile tests on foam tapes such as VHB) is a force per area: psi in the US, kPa, MPa or N/cm² elsewhere.

Adhesive coat weight is given in g/m² (gsm); some US converting specs use pounds per 3,000 ft² ream. Foam density for PORON, polyethylene and other foams is often in pounds per cubic foot (pcf) in the US and kg/m³ elsewhere.

Frequently asked questions