Every inkjet printer, whether it uses thermal or piezoelectric technology, has cartridges that hold water-based ink, printheads and nozzles that apply the ink to the paper. In piezoelectric technology, which is an Epson patent, a pocket full of piezo-ceramic material (crystals) resides near the back of each printhead. When a job is sent to the printer, a voltage gives the aforementioned material a charge and causes the crystals to expand and vibrate, ultimately forcing droplets of ink out of the nozzles and onto the paper.
This system is very similar to the far more common thermal inkjet technology, which uses heat rather than vibration to push the ink out. Because no heat is used in the piezoelectric inkjet printers, the types of ink that can be used is more extensive than thermal inkjet printers. Unfortunately, because this technology is not as widely used, the ink prices tend to be higher than those of standard inkjet cartridges.
Both types of inkjet printers can generate professional-quality images and documents, but the type of ink that can be used in some Epson photo printers, known as Archival Ink, has proven to be better than the standard ink when long-term durability is needed. Archival ink can resist water and light damage for up to 100 years and maintain vivid colors rather than fading over time. The protective resin coat makes this type of ink more durable, and its impressive color gamut keeps photos true to the original image.
So, if you are someone who requires long-lasting photo printing, piezoelectric inkjet models like the Epson Stylus Photo 700 might be worth considering. For most users, however, the lower prices and lower running costs of typical thermal inkjet models may be a better choice.