MedArray logo

Ink Degassing

PermSelect® PDMSXA-1000 Ink Degassers: PermSelect® PDMSXA-1000 Ink DegassersPermSelect® PDMSXA-1000 Ink Degassers

Dissolved gas and microbubbles in ink can significantly affect the speed and quality of printing. By interrupting droplet formation or pressurization at the ink head, dissolved gases can lead to improper jetting at the time of ink ejection. Beyond poor image quality, nozzle dropouts can cause expensive shutdown of the equipment, and the need for more frequent cleaning.

PermSelect's PDMSXA-1000 ink degassers (shown below) are ideal for degassing ink and are an excellent replacement for Pall's UltiFuzor TM (UDM-21110, Mimaki degassing module M801432)** and Membrana's SuperPhobic© membrane contactors*.

PDMSXA-1000 Ink DegasserPermSelect® PDMSXA-1000 Ink Degasser

A degassing performance comparison graph is shown below for the SuperPhobic© 1x3*, the UltiFuzor TM** (UDM-21110, Mimaki degassing module M801432), and the PermSelect © PDMSXA-1000. Note the wider range of performance for the PermSelect ink degasser which can result in reducing the number of degassers needed for a each color ink to achieve the desired level of degassing. Many printers use more than one degasser in series per ink color, which may not be necessary with the PermSelect © PDMSXA-1000.

Degassing performance comparison  for the SuperPhobic© 1x3, the UltiFuzor TM, and the PermSelect ©  PDMSXA-1000.Degassing performance comparison for the SuperPhobic© 1x3*, the UltiFuzor TM ** (UDM-21110, Mimaki degassing module M801432), and the PermSelect © PDMSXA-1000. Vacuum applied = 50 Torr, inlet water conditions 23 C, saturated with air. Data for the SuperPhobic© 1x3, the UltiFuzor TM obtained from data sheets published online.

Degassing ink with a membrane prior to it reaching the print head is a simple process. The ink flows on one side of the membrane, while a vacuum is drawn on the other side. Gases dissolved in the ink readily transfer through the membrane to the vacuum side, leaving the ink degassed when it reached the outlet.

PermSelect Ink Degassers PermSelect® PDMSXA-7500 Ink Degassers

For providers of ink in closed loop systems, a membrane degasser is used to degas the ink while filling the vacuum-sealed bags. Because the closed system does not allow air to contact the surface of the ink, as some bulk systems do, the need for additional degassing is minimized. This is especially important for white inks, which must be handled carefully to maintain suspension of the TiO2 pigment. In addition, degassing ink while packaging can reduce foaming, which otherwise will slow the fill process.

The diagram below depicts a typical ink degassing setup. Note that, if possible, the pump should be placed after the ink degasser to minimize trans-membrane pressure swings, and maintain a more stable pressure differential. Also, it is preferable to place any flow controlling valves upstream from the degasser. A vacuuum trap is optional to protect the vacuum pump in case of a leak develops.

How to Degass Ink: Degassing ink is simple and straightforward. Simply flow ink through the membrane degasser (lumen side) and apply vacuum to the opposite side of the membrane (shell side). Degassed ink exits the degasser. A small diaphragm vacuum pump is typically used asHow to Degass Ink: Degassing ink is simple and straightforward. Simply flow ink through the membrane degasser (lumen side) and apply vacuum to the opposite side of the membrane (shell side). Degassed ink exits the degasser. A small diaphragm vacuum pump is typically used as the vacuum source for the printer.

*3M, Membrana, and SuperPhobic are trademarks of 3M Company
**Pall and UltiFuzor are trademarks of Pall Corporation.