Journal of Food Processing & Technology

Towards high speed laser cutting of thin transparent polymer films

2^nd International Conference on Food & Beverage Packaging

June 13-14, 2016 Rome, Italy

Colin Dowding and Jonathan Griffiths

University of Lincoln, UK

Posters & Accepted Abstracts: J Food Process Technol

Abstract:

It has been shown that high speed laser sealing of polymer films to opaque polymer substrates is most effective when the laser wavelength is chosen so that the former is ostensibly transparent, resulting in a rise in temperature at the film/substrate interface. This raises a technical conundrum: the ideal sealing laser is therefore unsuitable for subsequent cutting of the film, a necessity for any non-contact production system. This work identifies and characterises a novel methodology to achieve cutting of highly transparent films at speeds of 250 mm.s-1 using a traversing incident fibre laser to incubate a moving superheated vapour. Through thermal finite element simulation and experimentation it is shown that application of a short initial dwell time followed by linear ramping of traverse velocity develops, accelerates and supports a flame front. Exothermic reaction of the highly absorbing polymer vapour incubated during the initial dwell acts as a secondary heat source, providing the energy required to facilitate cutting of the film.

Biography :

Email: cdowding@lincoln.ac.uk