导电油墨用镀银石墨粉的研制

Preparation of silver-plated graphite powder for conductive ink

将天然鳞片状石墨先进行化学镀铜、再化学镀银制得镀银石墨粉,通过扫描电镜观察了所制备的镀银石墨粉与直接镀银石墨粉及其球磨5h后的试样的表面形貌。将制备的样品用于印刷导电油墨,测试了镀银石墨粉的膜电阻率。结果表明,直接镀银的石墨表面镀层不均匀、覆盖率不高,球磨后银层发生大面积脱落;化学镀铜后再镀银的石墨粉镀层包覆程度高,晶粒尺寸均匀、致密,球磨后没有发生明显的镀层剥离现象。含该镀银石墨粉的导电油墨的膜电阻率为1.36×104·cm,导电性能达标。

The silver-plated graphite powders were prepared through electroless copper plating on the surface of natural flake graphite followed by electroless silver plating. The surface morphologies of the prepared silver-plated graphite powder and the direct silver-plated graphite powder as well as their samples ball-milled for 5 h were observed by scanning electron microscope. The prepared samples were applied to printing conductive ink, and the film surface resistivity was tested. The results indicated that the deposit on surface of the direct silver-plated graphite powder is ununiform with not high coverage, and the silver layer falls off in large areas after ball milling. The deposit on the graphite powder obtained by electroless copper plating initially and then electroless silver plating has high coverage, uniform particle size, and compact structure, and does not fall off after ball milling. The conductive ink containing the silver-plated graphite powder has a film surface resistivity of 1.36 x 10-4 .cm, showing a satisfactory conductive property.