Transparent silicone resin is commonly used in optical bonding processes which attaches the touch panel directly to the LCD, filling the small air gap between the front of the display and the back of the touch panel. The goal of optical bonding is to improve the performance of the display by reducing the amount of reflected ambient light under outdoor environments.1 Silicone resin is a flexible material and excellent in transparency, adhesion reliability, and durability to ensure higher quality of display images in terms of brightness and contrast. On the fact that silicon nanoparticles (SiNPs) is easily oxidized under atmosphere, it is expected that SiNPs can be used as an oxygen-getter in the silicone resin and a gas barrier creating a tortuous path in film. Thus we studied the introduction of SiNPs into silicone resin and their gas barrier properties, improving the resistance to oxygen transmission. First, SiNPs with halide functionalities were prepared from metal silicide, reacted with alkenyl magnesium halide to give alkenyl functionalized SiNPs, and then underwent the hydrosilylation with silicone containing Si-H in the presence of Pt catalyst to give SiNPs-imbedded silicone materials. These materials can be utilized themselves as optical clear resin or additives in commercial silicone resin for the display. The sheets of silicone resin with SiNPs (4-10 nm diameter) or films in which less than 1 wt% of SiNPs are dispersed were made and tested for gas (especially dioxygen) permeability. These film with SiNPs could be reduced about half the gas permeability of traditional silicone resin film (<280 barrier for O2; high light transmission: >99% in visible region). It may be expected that such SiNPs-imbedded silicone materials are particularly effective for incorporation into LCD module or the like which are susceptible to degradation from oxygen and/or moisture. Ongoing the study, we will present the synthesis and property of optically clear silicone resin with SiNP in details.
1. D. Lu, J. Wang, C. Li, J. Yuan, J. Sawanobori,J. Lin, A. Litke, M. Levandoski, “Liquid Optically Clear Adhesives for Display Applications” in 2012 International Conference on Electronic Packaging Technology & High Density Packaging, 13-16 Aug 2012, Guilin, Guangxi, China.