inktjet

Inkjet printing is a digital printing method that ejects tiny droplets of ink from a print head onto a substrate to form images and text. It is a non-contact process, enabling printing on irregular shapes and flexible materials, and it is widely used in consumer, prosumer, and industrial contexts.

The core concepts include two main classes: drop-on-demand and continuous inkjet. The drop-on-demand category uses mechanisms such as thermal inkjet, where ink droplets are formed by heating a small chamber, and piezoelectric inkjet, where piezo crystals create pressure to eject droplets. In continuous inkjet, a continuous stream of ink is broken into droplets and selectively deflected. Printheads contain arrays of nozzles; multiple colors are used for full color printing.

Ink types vary: dye- and pigment-based inks; aqueous, solvent-based, UV-curable, or latex formulations depending on substrate and use. Pigment inks offer lightfastness; dye inks provide bright colors. Substrates range from plain paper to photo papers, textiles, plastics, metals, and ceramics, often with surface treatment or coatings and sometimes requiring curing or drying.

Advantages include non-contact printing, high-resolution color, and compatibility with diverse substrates; disadvantages include higher ink costs per page in some cases, potential nozzle clogging, maintenance requirements, and slower speeds than some laser technology for bulk text.

History: Development in the 20th century culminated in the first commercial desktop inkjet printers in the 1980s. Since then, technology has evolved with improved print heads, inks, and industrial applications including packaging, textiles, and electronics printing.