Fabrication of LCD color filter using laser-induced thermal spray printing

The color filter of the LCD panel is fabricated using the laser induced thermal spray printing (LITSP) method, which ejects the ink droplets from the blind-holes of the donor plate to the substrate by the bubble pressure due to rapid laser heating. The compositions of the dye and pigment inks are determined experimentally, which consists of 5% colorant, 24% epoxy, 6% hardener, 5% xylene, 30% n-butanol, and 30% BCA. The effects of the laser power and travel speed on the quality of the print pattern are analyzed experimentally. The phenomena of ink ejection are investigated numerically through thermal and fluid dynamic analysis. The ink droplet is transferred successfully when the top surface of the hole in the donor plate is heated above 122 °C for longer than 10 ms. The quality of the print pattern is enhanced by employing the laser- and fume-masks, which provide the localized heating on the top surface of the hole and remove the satellite droplets and fume.