Inkjet printers can be used as a replacement for a high priced imagesetters and low quality laser printers. Epson's use a room temperature mechanical, piezo technology of precise electrical pulses that cause the ink reservoir wall in the head to compress, projecting ink through the nozzle. Programmers can also control the exact placement, size, and shape of each dot then shape with the millions of ink droplets they eject in each square inch. For screen printing, we need a one color printer, not an 8 color printer. RIP programmers can increase ink deposit to make the transparent ink designed for CMYK printing of multi-color photographs opaque enough to block UV light.
Canon and HP printers use thermal heads that heat the ink to 500°F over and over, producing a vapor bubble in the ink reservoir (bubble jet). When the ink expands, droplets are ejected through the nozzle. This cannot be increased with RIP programming. One of the side effects of the high heat is that the cooling phase alters critical nozzle alignment.
To make screen printing positives with an inkjet printer, you must have an absorbent coating on clear film. Ulano Pigment Inkjet Films are designed to make positives. Dye inks are 100% liquid and can be absorbed by a swellable coating like the gelatin in indirect stencil films. Pigment inks require a micro porous coating with microscopic cavities that can absorb the resin coated pigment particles with natural capillary action.
Ulano Pigment Inkjet Film is compatible with dye or pigment inks.
Often, nano porous or micro porous coatings are mistakenly called water proof. If you lick your fingers and pinch a piece of film, you will make one side sticky as it absorbs the moisture with capillary action. Dye inks re-wet and bleed if you get water on them. When the majority of inkjet printers used water based dye ink, suppliers started selling the more expensive micro porous coating as "water proof" to printers who wanted to pay for a safer coating in case their staff spill something on the positive. Pigment Inkjet Films are made to absorb water based inks, but they are not waterproof, rather they are "bleed-resistant".
Required temperature for optimum performance : 60° – 80°F (15° – 25°C)
Required humidity for optimum performance : 40% – 60% RH
(Note: High humidity will prolong the drying time or the ability to absorb ink)