Digital printing systems for printed circuit board legends

摘要

The development of digital printing systems for printed circuit board legends (a.k.a. nomenclature, indent or letter screening) is a major technological leap. Legend marking on printed circuit boards (PCB) is presently being accomplished with screen-printing. This method of marking legends on PCB's provides a permanent, high contrast mark, however, this technology is costly in terms of material and labor. Screen-printing is a mature technology that is well understood in the industry and well supported by screen ink providers. A successful digital printing solution for this application will retain the benefits of permanent, high contrast marks and offer advantages of demand printing including efficient runs of small production batches. An emerging technology in PCB legend marking is drop-on-demand (DOD) ink jet. DOD ink jet offers the flexibility of digital printing while also providing high contrast, high resolution marks with the required performance properties. The primary advantage of DOD ink jet printing enables PCB's to be printed directly from image files eliminating the need for screens and greatly reducing the setup time required between batches. As the PCB industry is challenged to reduce costs and improve turnaround times, drop-on-demand ink jet shows promise in reshaping the printing process.