Non-fraying wash-resistant labels cut from thermoplastic strip - with blunt edged heated blade which forms thick fused edges

A method of transversely cutting up a thin thermoplastics fibres strip, to form individual labels with non-fraying edges which are resistant to repeated washing, is as follows: a localised transverse band across the strip is continuously melted, so that the melted material penetrates right through the thickness of the strip and also permeates longitudinally on either side and is pressed into the interstices between the fibres; the material is then rapidly cooled and hardened on the face opposite to the application of pressure so that it bonds into the voids. Pref., a heated blade with a blunt edge and steeply inclined lateral surfaces is applied to one side of the strip, while a cold plate is used as an anvil on the opposite side. Sufficient material remains on either side of the inclined surfaces of the blade as it cuts through the heated portion to form thoroughly bonded anchorages which prevent fraying along the cut edges of the strip.