IC lead-frames are multi-connector units usually formed by stamping processes utilizing a continuous web of material.  The various connector elements usually remain attached to the parent web until the connector elements are mounted and fixed into an electrically insulating housing. 
Because the connector elements are quite fragile and are usually connected to the parent web at only one of their ends, it is not an uncommon practice to employ a taping procedure whereby small, rectangular pieces of tape are applied to the lead-frame adjacent to the loose ends of the connectors. 
One basic method of achieving the taping involves feeding a strip of tape from a supply thereof to an appropriate position over a lead-frame and cutting a rectangular strip from the center of the tape and applying it to the lead-frame.  This method provides a great deal of scrap which must be taken up by another spool. 
Another method, which is scrap-less, removes a segment of tape that is the full width of the strip; however, in order to tape a lead-frame on four sides; i.e., where the tape segments form a hollow rectangular or square, four tape supplies are needed: a system which is quite complicated and expensive.