MICR toners are necessary to make the processing of checks easier and faster. They enable the reader-sorter machines that banks use to recognize the information that MICR lines carry; they are the reason why automation in check processing is possible.

How do MICR toners make automation of check processing possible?

The Nature of MICR Toners and the MICR Reading Process

MICR is short for magnetic ink character recognition. As its name suggests, MICR toners have magnetic components in the form of iron oxide additives. These iron oxide additives are the reason why reader-sorter machines can read checks.

When a check is fed into the reader-sorter machine, the MICR line passes across a check to make the iron oxide magnetized and emit a signal. Afterwards, the check is read by a magnetic read head. The contact between the magnetized MICR line and the magnetic read head creates an electromagnetic field, also called a flux pattern.

The flux pattern in turn creates a current in the read head. This allows the characters in the MICR line to be recognized by the machine. The strength of the flux pattern and the timing of the line's passage under the read head are essential in determining the accuracy of the character recognition.

The Waveform Theory

The MICR reading process works using what is called the waveform theory. To put it simply, the signals emitted by the magnetized characters printed with MICR toners on the MICR line create corresponding waves. The peaks of these waves, both positive and negative, must be of the right height or depth in order for the reader-sorter machine to make the correct reading. The position of these waves must also be in the correct grid.

This is why accuracy is so important when it comes to printing checks with MICR toners. The correct percentage of iron oxide additives in the MICR toner itself contributes to the signal strength of the reading. If the signals are too weak or too strong, errors will occur in the peaking of the waves. The position of the waves allows the machine to anticipate the signals and thus recognize the character being read. If the printed character is skewed or is not in the correct size, the machine would get the wrong signals and fail to read the printout.

There cannot be any variations in the peaks or in the position of the characters printed with MICR toners. The reader-sorter machine would find them impossible to read.

The Importance of Choosing the Right MICR Toner

Given the way reader-sorter machines process checks, it is important that you use a good quality MICR printer and a good quality MICR toner when you do your check printing. If the printer does not print it correctly, where there are voids, spotting, clipped edges or blurred lines on the MICR line, the machine would not be able to read the printout. The same goes if the MICR toner is not of the correct formula or does not have the right amount of iron oxide additives.