Characterization of Endocrine Disruptors and Particulate Matter Emissions from Laser Cutting of Plastic Film in the TFT-LCD Industry

Abstract

In the last five years laser cutting has been identified as one of the solutions for converting and shaping the plastic films used in the Thin Film Transistor Liquid Crystal Display (TFT-LCD) industry due to its positive effects on cost management. However, there has been quite limited information available with regard to the hazards of the air pollutants released during the laser cutting process, and in particular in relation to the real operations that occur in a factory. This is the first study that aims to assess the Endocrine Disruptors (EDs) and Particulate Matter (PM) emitted during the laser cutting process. Phthalate Esters (PAEs) and Polycyclic Aromatic Hydrocarbons (PAHs) are the representative EDs in this research. The results indicate that the power of the laser and type of plastic significantly affect the composition of air pollutants. Di(2-ethylhexyl) phthalate (DEHP) of PAEs was identified in the Laser Generated Air Contaminants (LGACs) from both Polycarbonate (PC) and Polyethylene Terephthalate (PET) films. DEHP was detected in the gas-phase LGACs of PC and PET at low, medium and high power (80 W, 160 W, 240 W), but not detected in the particle-phase LGACs of PC and PET, except when the laser was operated at a low power setting. With the laser power increased, the concentrations of PM and PAHs also increased. This research found that during laser cutting PC released more DEHP than PET, but PET released more PAHs than PC.

Long-term Multiple Chemical Exposure Assessment for a Thin Film Transistor Liquid Crystal Display (TFT-LCD) Industry

“…However, recent epidemiological studies conducted in a photolithography industry have shown that long-term exposure to ethanol and acetone might result in workers with irregular menstrual cycles and endocrine disruption (Hsieh et al, 2005;Lin et al, 2013a). In a liquid crystal display (LCD) manufacturing factory, longterm exposures to multiple chemicals of low levels might lead to premenopausal female workers with modest changes in their reproductive hormone urinary concentrations (Lin et al, 2013b;Chan et al, 2017). A slightly increase in kidney dysfunction risk was identified for workers in a TFT-LCD industry (simultaneously exposed to IPA, PGMEA, and propylene glycol monomethyl ether (PGME)) with their total exposure levels ≥ 50 ppb for 3-5 years (Chang et al, 2010b).…”