- Character size
Inkjet Coding and Printing methods
On-demand type inkjet Printers
With this method, only the amount of ink particles necessary for printing are discharged.
The ink nozzles are arranged vertically within the printer. Ink particles are instantaneously discharged from the nozzle and are sprayed on the target. Piezo, thermal, and valve are the methods used to apply pressure to the ink particles and discharge them.
Piezo method [Office/industrial use]
In this method, a piezoelectric (piezo) element, whose volume is deformed when voltage is applied, is used to discharge ink particles. This element is attached to the component that is filled with ink. Then, the volume deformations are used to apply pressure to the ink, which discharges ink particles from the nozzle.
|Advantages||- The amount of ink discharged can be controlled with high accuracy by controlling the voltage.
- Because it does not apply heat to the ink, this method is highly durable and resistant to the influence of the operating environment.
|Disadvantages||- Because a piezo element is required for each nozzle, the structure can easily become complicated.
- It is easy for nozzles to become clogged if bubbles form in the ink.
Thermal (bubble) method [Office/industrial use]
In this method, a heating element is used to apply heat to the ink, which causes bubbles to form and discharge ink particles. The heating element is attached to the component that is filled with ink. Applying heat to the ink causes a bubble to form, which discharges ink particles from the nozzle.
|Advantages||- The structure is comparatively simple, which makes it easy to miniaturize these printers.
- It is easy to improve the printing resolution.
|Disadvantages||- It is easy for the ink to deteriorate due to the heat applied.
- Print heads have short service lives.
- Because the nozzle's water content evaporates, it is easy for the nozzle to be clogged due to drying out.
Valve method [industrial use]
In this method, a solenoid is used to open and close the nozzle cover, which discharges ink particles.
By opening and closing the valve, the pressurized ink is discharged from the nozzle.
|Advantages||- Because pressurized ink is discharged, it is easy to increase the distance from the nozzle to the target.|
|Disadvantages||- Because the ink particles are large, it is easy for the print quality to degrade.|
Continuous type inkjet coders
In this method, ink particles are continuously discharged from the nozzle.
The ink particles are charged, and deflecting electrodes are used to deflect the ink particles so that they are sprayed on the printing surface. Ink particles that are not deflected are collected, returned to the ink tank, and reused. Even when printing is not being performed, ink is continuously discharged at all times, which is why they are called continuous-type printers. This is the most commonly used method among industrial-use inkjet printers.
|Advantages||- Because ink is discharged at high pressure, highly viscous ink can be used.
- Because ink is discharged continuously, quick-drying ink can be used.
|Disadvantages||- Due to the large-scale structure, it is difficult to miniaturize these printers.
* These printers are not suited for office use.