In January 23, 2003 Lexmark announced the release of their T420d and T420dn monochrome laser printers for small and medium-sized businesses. At 22 pages per minute, only 10 seconds to first print, a duty cycle of 50,000 pages per month and standard automatic duplexing, the T420 packed a lot of features for a laser printer under $650 (street price at time of release).

The T420 cartridge is a “clamshell” design, but with a more square shape and a bit smaller than the cylindrical Se, T, T520/522 & T620/622 new style cartridges. A direct contact chip (very similar to E320) is located on the waste bin section and is held in place with one screw, and a unique encoder wheel includes the familiar “Pac-man” gear.

A plastic shipping lock (similar to that on the E320) has a wrap-around foam to protect the drum.

Toner sensing is accomplished through the encoder wheel and chip working together. Testing is in process to determine if the wheel and chip are a matched set.

At present Static Control’s Imaging Labs have seen two versions of the cartridge.

Ricoh/IBM InfoPrint 1222