Near-UV, visible and IR pulsed laser light interaction with cellulose

Immediate as well as long-term effects of pulsed lasers operating at three different wavelengths (308, 532, and 1064 nm) and fluences below 2.5 J cm(- 2) on cellulose are reported. The degree of polymerisation was determined v iscometrically, whereas diffuse reflectance FTIR was used to gain insight i nto the changes in the chemical composition. A strong immediate cellulose d egradation effect after excimer laser treatment at 308 nm was observed. Las er irradiation at 1064 nm resulted in an increase of the degree of polymeri sation due to the formation of inter- and intra-molecular ether bonds. Nd:Y AG processing at 532 nm resulted in no detectable chemical changes after th e treatment, although longterm resistance appears to be impaired. PACS: 42. 62.-b; 61.80.Ba; 83.80.Lz.