Effects of Sweller on the Removal of Smear from the Epoxy Resin

• Main Authors: Yung-Chi Cheng, 鄭永琦
• Other Authors: Meng-Hui Li
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/72645861935745794663

碩士 === 中原大學 === 化學工程研究所 === 96 === Abstract The demand trend for multifunctional electronic products has led to the development of multilayered printed circuit boards using glass-fiber reinforced epoxy resin as the substrate of insulating material. Holes are drilled through these boards and the drilling leaves a smear of insulating material on conductive surface which needs to be removed prior to deposition of conductive material. The industrial practice of desmearing utilizes a sweller prior to oxidation of the smearing material. Because the amount of sweller absorbed will affect the outcome of oxidation, it is necessary to select the appropriate sweller concentration, operating time and temperature to maximize oxidation with the aim of lowering the operating costs. This study consists of three parts: (1) Determine the effect of using sweller on epoxy surface properties. By changing the surface to become more hydrophilic, it made easier the transport of the oxidizer in the resin and thus enhanced oxidation. (2) Investigate the absorption of sweller by epoxy resin. Using Arrhenius equation to relate diffusion coefficients with temperatures, the study obtained Ea to be 112, 115 and 125 (kJ• mol-1) and D0 to be 35, 1706, 319571 (10-9• cm2• min-1) for sweller concentration of 50, 75, 100 vol% of Solvent-II. (3) Investigate the relationship between the amount sweller absorbed and epoxy removed. It was found that optimum weight loss is obtained from using sweller concentration 75 vol% of Solvent-II at 353.2 K and for 2 minutes.