Ultrafast Laser Engraving Method to Fabricate Gravure Plate for Printed Metal-Mesh Touch Panel

Weiyuan Chen,Yuming Wang,Shengyu Lin,Hong Hocheng,Tahsin Chou,Yuli Yen,Wenlang Lai,Kaijun Wang

doi:10.3390/mi6101433

Abstract

In order to engrave gravure plate with fine lines structures, conventional art used lithography with dry/wet etching. Lithography with dry/wet etching method allows to engrave lines with smooth concave shape, but its disadvantages include difficulty in controlling aspect ratio, high and uniform in large size process, substrate material limitation due to etching solution availability, and process complexity. We developed ultra-fast laser technology to directly engrave a stainless plate, a gravure plate, to be used for fabricating 23 in. metal-mesh touch panel by gravure offset printing process. The technology employs high energy pulse to ablate materials from a substrate. Because the ultra-fast laser pulse duration is shorter than the energy dissipation time between material lattices, there is no heating issue during the ablation process. Therefore, no volcano-type protrusion on the engraved line edges occurs, leading to good printing quality. After laser engraving, we then reduce surface roughness of the gravure plate using electro-polishing process. Diamond like carbon (DLC) coating layer is then added onto the surface to increase scratch resistance. We show that this procedure can fabricate gravure plate for gravure offset printing process with minimum printing linewidth 10.7 μm. A 23 in. metal-mesh pattern was printed using such gravure plate and fully functional touch panel was demonstrated in this work.

Highlights

Printing process provides a fast, continuous production with low production costs and pollution, and becomes a key process technology in printed electronics [1,2]
There are three different engraving methods that can be used for fabricating gravure plate
Fabricating gravure plate by wet etching process after lithography is popular in industry

Summary

Introduction

Printing process provides a fast, continuous production with low production costs and pollution, and becomes a key process technology in printed electronics [1,2]. Owing to its high line resolution, the gravure offset printing technology may replace the current photolithography process and is considered as the advanced manufacturing technology for generation electronic products [6]. The key issue of gravure offset printing process is the gravure plate, which transfers the designed pattern to be printed. There are three different engraving methods that can be used for fabricating gravure plate.

Results

Conclusion