The effect of microscopic features upon the transmissivity of enclosed laser ablated laminated metallised polymer films

Enclosed laser ablation of aluminium films using a continuous wave diode laser: II—Theoretical heating considerations and proposed mechanisms

“…A second, and more important point, is that the maximum temperature achieved at 10 W (for 2 mm s −1 ) is just over 410 • C, well below the aluminium melting temperature of 660 • C and yet, at this temperature, the polymer ÿlm is completely destroyed. The aluminium cracking mechanism occurs at 10 W and 8 mm s −1 [3] and yet, the maximum temperature achieved here is 104 • C, suggesting that the mechanism by which aluminium cracking occurs features both solid aluminium and solid polymer (OPP mpt = 190 • C).…”

“…The total 70 m thickness of polypropylene used absorbs a negligible amount of radiation (on average approximately 0.15%) and re ects 11.7% of wavelengths 400 -1400 nm [3]. Fig.…”

“…For the OPP polymer (across which the thermal wave must travel), the value of is 6:37 × 10 −8 m 2 s −1 [3]. Eq.…”

Multiple pulse heating cycles during the enclosed laser ablation of a laminated metallized polymer

“…As has been mentioned above, the samples for transmission spectrum analysis were of ten lines each 0.3±0.4 mm in width so that they were large enough to be scanned using the spectrometer probe. Changes in the transmissivity of the ®lm can be used as indicators of both the degree of demetallization and the degree of polymer damage [9].…”

“…A Taly-Surf roughness probe was used to measure the depth changes across the outer surface of the polymer ®lm. Changes in roughness are proportional to changes in polymer distortion within the ®lm [9].…”