Donor writes, "Following the successful development of silicone-molded dual inline packages by Signetics in the late 1960s, other companies began experimenting with cheaper epoxy-molded packages in the early 1970s, and this created a major transition away from ceramic packages, and into plastic dual inline packages. Following the earlier ceramic technology, these plastic DIP packages were often configured as pre-molded DIPS, containing die attach pads and gold plated leadframe tips. Eventually, other companies, led by National Semiconductor, began manufacturing epoxy molded dual inline packages as post-molded configurations in the early 1970s."