Printed Circuit Design & Fab - July 2008 - (Page 42)

SOLDER MaSk efficiency, exactly the same, was a challenging task. The new formulation performs to the required industry standards, as well as having other essential production favorable characteristics compatible with the inkjet process. Ink particle size and distribution. For inkjet inks, the filler particle size is critical for print head performance and maintenance. Solder mask ink must exhibit an average particle size in the sub-micron range, with a very narrow particle size distribution. This property is common for inkjet inks but is definitely unique for inks used in solder mask material. In order to achieve this feature while keeping other essential properties, suitable raw materials must be selected as well as applying an effective grinding procedure. Minimizing ink particle size requires the addition of unique surfactants to ensure consistent ink performance. It should also be emphasized that both previously mentioned parameters are theoretically contradictory to each other, since particle size reduction tends to increase the mean viscosity. As a result, the inkjet solder mask is a sophisticated formula that contains a high solids content with nano to micron scale particles, while maintaining very low viscosity suitable to the jetting parameters, with desirable dried film properties comparable to other industry accepted solder mask materials. Another important factor for solder mask performance is its curing system. The inkjet solder mask ink uses two curing systems, a UV and a thermal initiated cure. This hybrid, patent pending formula integrates the benefits of each system, precisely adjusting the performance to meet the demands of the digital inkjet environment. Considering the environmental benefits of the digital printing solder mask process, both machine and compatible ink offer an ecologically friendly approach to the development and production process. The ink ingredients were carefully selected to minimize VOC and other irritating or harmful components. The formulation is RoHS approved and the dry film passes UL 94 V-0 grade. The PCB industry is moving aggressively into the age of digital printing, with the adaptation of inkjet printing for imaging, solder mask and legend inks. In some applications, inkjet will also be used to selectively build circuit traces with an additive application of conductive materials. The operational benefits of these systems are clear. The technological advantages that can be achieved by digital solder mask printing will have a major impact on the future of the PCB industry. pdc&f yEhuda david is the product manager of Greenjet and Dr. yiFat BarEkEt is vice president – chemistry for Printar ltd. They can be reached at yehuda_d@printar.com and yifat_b@ printar.com respectively. “Ventec laminate has been a tremendous asset in Titan PCB East’s ability to provide a high quality, high reliability lead free product to today’s time critical, cost sensitive market. Ventec VT-47 provides superior peel strength, high Td, Z-axis stability, thermal reliability, surface quality and inventory selection all in the same package. The fact that this is provided in a cost competitive manner is icing on the cake. Ventec is not just a player in the game, they are a top performer. The addition of VT-90 polyimide materials to the FR-4 offerings make Ventec a force to be reckoned with in the future.” Mike Berg, President and CEO, Titan PCB East – Amesbury, MA “When using the VT-47 and VT-481 materials, we have found above average drill and scoring characteristics without experiencing the fracturing and haloing associated with other well-known lead free comparable phenolic resin systems.” John Gratton Engineering Manager Century Circuits – Toronto, ON “We have been very pleased with the quality, service, performance, and consistency of the Ventec materials for almost two years now. I would not hesitate to recommend Ventec VT-47 to our customers as a reasonably priced alternative for lead free assembly.” Robert E. Welch Process Engineering Manager Waytec Electronics Corp. – Lynchburg, VA “The family of Ventec laminates has made an improvement in our processing of multilayer circuits. The materials exhibit very good consistency. Our quality with the performance of these laminates.” department is very satisfied Jim King Process Engineer Philway Products – Ashland, OH 16 Hunt Rd. South • Amesbury, MA 01913 • (978) 388-9610 • (978) 388-5339 fax • www.globallaminates.com Sales reps and distributors wanted: email Bruce at bhurley@globallaminates.com 42 Global Laminates Inc. printEd circuit dESign & fAB JULY 2008 http://www.globallaminates.com http://www.globallaminates.com

Table of Contents Feed for the Digital Edition of Printed Circuit Design & Fab - July 2008

Printed Circuit Design & Fab - July 2008

For optimal viewing of this digital publication, please enable JavaScript and then refresh the page. If you would like to try to load the digital publication without using Flash Player detection, please click here.