Laser cutting of paper

It is commonly known that CO2 laser beam is suitable for paper and board cutting. However there exists quite little published research work about paper cutting with laser. Lasers at paper industry are mainly used to different perforating and scoring applications. There exists only few paper slitting applications. Water jet cutting is widely used edge trimming applications at paper plants. Laser cutting could be substation process for water jet cutting.This paper concentrates on understanding parameters that are characteristic to the laser cuttability of coated and uncoated papers. Also economical aspects, for edge trimming of paper web, are studied. This study was performed within a national project in Finland about laser cutting of pulps, papers and boards. The research was carried out with a Trumpf 2.7 kW HQ laser and a work cell designed and manufactured for the project.The cutting experiments contained the cutting tests of how different laser parameters like power, focal point position, and focal length affected the cutting speed and the cut edge quality. Papers used in study could be laser cut with acceptable quality. Highest cutting speeds were noted with 127 mm focal length. It was also found that the cut edge quality and kerf width were stable for each grammage and paper types produced with parameter combinations on cutting limit (laser power/cutting speed)