Why Humidity Matters in Dye-Sublimation
Learn about humidors and why your wide-format dye-sub printer might need one

In most states, it is not hard to find a working room with a humidity of 35-45% to keep your dye-sub inkjet printers in a controlled state. Often those areas are along the rivers or oceans and the heat is the most challenging issue.
There are some very arid states, such as Arizona, Colorado, Nevada, New Mexico, Utah, Wyoming, and others where the humidity is quite low and will cause your printer’s inkjet head to clog due to the dryness. The situation can get aggravated by any forced air heating systems.
General industry recommendations are to keep the dye-sub printers in a closed room with a good quality humidifier that can cover the room’s cubic space and keep the humidity at a consistent 35-45% humidity. This also assures you that your print room is clean and free of outside dust. Additionally, most dye-sub printers will require more attention to keeping them clean.
Select a humidifier and a water source that does not contain hard mineral deposits, as these can create white chalky dust or film. Using demineralized or purified water is best. You also need to clean your humidifier often and effectively.
You can make a choice on smaller, commercially available ultrasonic, cool mist, or warm mist units. Larger systems are also available for larger print rooms.
Quite often, dye-sub printer users will place a small plastic tray or empty maintenance tank in their printer cabinet with a slightly water-filled absorbent sponge to allow the humidity to fill the printer cabinet by the print head and pump cap assembly. We call this little device the “humidor, ” and it has saved a lot of printers over the years!

Be sure to remove the humidor before you start to print. Hanging a colorful ribbon on the tank is a good idea, as well as a notecard over the printer controls as a reminder to remove the humidor from the cabinet before use.

Learn more: Get more details on wide-format dye-sub printer upkeep in Part 1 and Part 2 of Halley’s preventative maintenance series.