What is Drop on demand printing?

The first DOD non-contact inkjet printer was introduced in the 1980s recently it has been used for industrial applications and tends to be used for more demanding industrial applications. However, it is not recommended for most retail packaging due to their lower printing resolution.

DOD is the broadest classification of inkjet printing technology and is commonly sub-categorized into:

  • thermal
  • piezo

The printing process:

Depending on the DOD system type it will either use thermal or piezo technology.

In thermal printing technology, drops are formed by heating a resistive element in a small chamber that contains the ink. The temperature rises causing a thin film of ink above the heater to vaporize which creates a bubble causing a pressure pulse that drops ink through the nozzle.

Piezo uses electric technology to drop uniform droplets of ink onto the substrate. It starts with the voltage being applied to a channel then the electric effect takes place.

Then the channel will become enlarged as it is filled with industrial ink. The voltage is applied to the next channel which also enlarges at the same time the other channel shrinks as it drops the ink.

The DOD process starts by drops being formed by the creation of a pressure pulse in the ink reservoir. This causes valves open and close to form ink drops on demand drops are ejected through the nozzle according to the printing requirement. 

It can be used in a variety of ways:

DOD can be used in a variety of industries for both secondary printings such as boxes and bags. Or As mentioned before this system is ideally used on demanding industrial applications and primary printing such as steel beams, various metals and plastics. Can be used for printing on a large variety of porous and non-porous substrates.

They are commonly used for date and time coding or serial numbers can be used to print this in large character and coding requirement.

The benefits of using this printing method:

The main reasons these machines are a popular choice is because they are easy to use, versatile, reliable and cost-effective.

These machines are quick and easy startup and the simple design makes the process is easy to operate.

Not only does it produce cost-effective inkjet printing because of the robust design they also require low maintenance and this will lower maintenance service costs.

The DOD system is viewed as versatile because it can be mounted in various ways enabling printing in any direction.

DOD ink is available from Needham Ink