A Universal Quick Guide To Hardness Testers Including Electronic Capture Of Test Data And Online Data Transfer

By Walter Friesendorf, Pharmatron

Hardness tester technology has progressed significatly since the patent for a handheld manually operated hardness tester was assigned to Monsanto in 1936. Described in the patent application as an "Apparatus For Testing Pharmaceutical Tablets" this primitve tester, still being manufactured to this day, continues to play a role for some tablet manufacturers in setting up tablet presses and believe it or not still serves, in some places, as the primary production and quality control handness tester.

One of the first mechanized testers to measure tablet hardness using weights and cable activated pulleys was introduced nearly 33 years later. Known as the model 2E it had a measurement range of 0-20Kp and is still actively sought after in the used hardness tester market. The next evolutionary step for analog testers was the introduction of technology employing a mechanical link to move the measuring weights instead of pulleys. The model 4M offered improved precision and repatability coupled with a user friendly digital readout.