A smartphone screen protector that remains unscathed even when dropped from a height or forcibly scratched with a hard pencil tip is moving closer to commercialization.
A Korean research team has drawn attention by developing a next-generation protective material that resists scratching while flexibly absorbing impacts, using an "interface engineering" technique that precisely controls the boundaries between materials.
The Gwangju Institute of Science and Technology (GIST) announced on the 4th that a research team led by Kang Hong-kyu, deputy director of the Next-Generation Energy Research Institute, has developed a manufacturing technology for a protective film that is both hard and shatter-resistant. Rather than changing the material itself, the team precisely controlled the "interfaces" where different materials meet.
The research simultaneously addresses the limitations of conventional materials, which are either strong against scratches but weak against impact, or strong against impact but easily scratched. It is significant in that it demonstrates the feasibility of a protective material that can meet the durability required in real-world use.
The team comprehensively verified performance through scratch tests, drop and impact tests, optical transmission measurements, and repeated durability tests.
The results showed that almost no scratches occurred even under strong friction at a pencil hardness level of 7H, equivalent to a very hard pencil tip. The material also maintained its structural stability without damage under an impact of 40 joules, comparable to the force of a small object falling rapidly.
When applied to an organic solar cell module, the material showed improved mechanical stability and reliability compared with conventional polycarbonate-based structures.
In additional repeated bending tests, flexibility was maintained without performance degradation, confirming its applicability to various forms such as large-area panels and curved displays.
The work is highly regarded for implementing a protective material platform that satisfies surface hardness, impact resistance, optical properties, and flexibility all at once, by simultaneously realizing interface bonding and structure formation within a single process.
"This research is a general-purpose protective material technology that resolves the trade-off between surface hardness and impact resistance through interface engineering, securing both characteristics at the same time," Kang said. "It can be expanded into a platform technology applicable to various industrial fields such as displays, solar cells, and mobility, as well as to large-area processes."
The research was supported by the Nano and Material Technology Development Program of the Ministry of Science and ICT and the National Research Foundation of Korea, as well as the Deep Tech TIPS program of the Ministry of SMEs and Startups. The technology was also recognized for its excellence by receiving an AA rating from the Patent Analysis and Evaluation System of the Korea Invention Promotion Association.
