Inkjet Fundamentals
What is Single Pass Inkjet?
Single pass inkjet means that the printhead stays fixed in position and ink is ejected directly on the substrate as the media passes under the printhead. This means that the maximum print width will be determined by the size of the printhead. For the 1170 printhead that is 11.69” or 297mm
Single Pass Printing Pros
High Speed
Affordable
Easy Setup
Thick and Rigid Substrates
Single Pass Printing Cons
No Nozzle Redundancy
Limited Resolution / Quality
Ink Type Determines Substrate
Substrate thickness needs to be uniform
Types of Ink & the Pen Test
Thermal inkjet uses heat to eject ink from the nozzle. This limits the types of inks that can be used as certain solvents are flammable and have issues when they are heated. This also limits the type of colorant that can be used as burnt chemicals may cause nozzle blockage.
The 1170 printer uses a water based pigment based ink developed by HP. The substrates compatible with this ink need to be porous so that the ink has something it can absorb into.
The pen test is a quick test that can be done on substrates to determine if a substrate is a good candidate for the 1170 printer. A water based felt tip marker is the best type of pen to do this test such as the Pental S520-A.
To do the test, mark the substrate and immediately rub the mark to see if the ink dries.
If the ink dries immediately the substrate is a good candidate for water based ink
If the ink dries after a few seconds, the substrate may be compatible but may require a dryer
If the ink never dries, the substrate will not be compatible
Using a permanent marker is not usually recommended for this test as it uses a solvent to help dry the ink, however, if a permanent marker doesn't dry immediately, the substrate will probably not be compatible with water based ink. To determine if a permanent marker dries immediately, the mark should not be able to smear immediately after testing the substrate.
Dye vs Pigment ink
For detailed info on the FI-1000 Printhead and BNB, see “About the FI-1000”
Maximize your printhead life
Thermal inkjet nozzles have an expected life. For this reason the printbar is a consumable part in the 1170 printhead and is expected to be replaced over time.
Below are some tips to maximizing the life of your printbar
Avoid any contact with the printhead as much as possible. It is important that media isn’t rubbing on the printhead or it is not coming in contact with other items such as debris, dust, or the transport
Run a cleaning after printing dusty substrates. This will ensure that the nozzles push out any debris
If the printer is not being used, run a cleaning cycle or some test prints to make sure the nozzles do not dry out over time
Try to utilize the entire printbar width when possible - this will spread out usage evenly among all the nozzles
Optimize artwork and page rotation to avoid lines in the direction of belt travel when possible. Small lines use a very small number of nozzles
What Is Thermal Inkjet?
From Wikipedia:
To eject a droplet from each chamber, a pulse of current is passed through the heating element causing a rapid vaporization of the ink in the chamber and forming a bubble, which causes a large pressure increase, propelling a droplet of ink onto the paper . The ink's surface tension, as well as the condensation and resultant contraction of the vapor bubble, pulls a further charge of ink into the chamber through a narrow channel attached to an ink reservoir. The inks involved are usually water-based and use either pigments or dyes as the colorant. The inks must have a volatile component to form the vapor bubble; otherwise droplet ejection cannot occur. As no special materials are required, the print head is generally cheaper to produce than in other inkjet technologies.