Ryonet | #PoweringThePrint
The concept behind inkjets and exposing film will be familiar to most readers: ink gets squirted out of nozzles located within the print head, which distribute the ink across the page as it is fed through the printer. It’s less well known, though, that the technology itself can be broken down into two common types: thermal and piezo.
Although both distribute ink in a similar fashion, the difference lies in how they transfer the ink to the page. In thermal inkjets, the nozzles located inside the print head are heated to create a vapor bubble which forces a droplet of ink onto the paper. Due to the nature of the ink transferal method, many manufacturers refer to these types of inkjet printers as bubble jets. Manufactures producing bubble jets include HP, Canon and Lexmark.
In contrast, piezo printers squirt pressurized ink through the nozzles by charging the piezo crystal located behind the nozzles in the print head with electricity. Piezo crystals vibrate when charged with electricity and this, in turn, pulls and then pushes the ink within the nozzle. By varying the strength of the electrical charges, the technology causes different-sized ink droplets to break away from the nozzle. Also called the vibration method, the technology was patented by Epson and is consequently used in its range of inkjet printers.
This is a PostScript interpreter called a Raster Image Processor or RIP. Without PostScript it is impossible to print high-quality halftone dots on a “non-PostScript” inkjet printer such as an Epson 2200 or 4000. Even if your printer has PostScript, it may not be able to print halftone dots because PostScript is often just used to calibrate and balance colors on an inkjet. The Epson “RIP” does not print halftone dots! FastRIP does!
A plotter is a vector graphics printing device that connects to a computer. Plotters print or cut their output by moving a pen/knife across the surface of a piece of paper or film. This means that plotters are restricted to line art, rather than raster graphics as with other printers. They can draw complex line art, including text, but do so very slowly because of the mechanical movement of the pen/knife. (Plotters are incapable of creating a solid region of color by pen)
When computer memory was very expensive, and processor power was very slow, this was often the fastest way to produce color high-resolution vector-based artwork, or very large drawings efficiently. Plotters coupled with a hand-cut water soluble film that is weeded out in a negative form after cutting then applied to a screen, this is but one option to a printer that’s already doing vinyl signs.
In addition to this blog you can learn more info about screen printing here as well as sign up to take a Screen Print Experience class about screen printing and get one on one instruction and learn from the pros.