Two-Step Glass Molding Process for Forming Glass Edges with Obtuse Angles for Mobile Displays

The domain of edge displays with 2.5D or 3D curved designs has been expanded to improve user convenience. The currently available 3D cover glass offers a limited curvature radius of at least 5 mm and a curvature less than 88 degrees, due to limitations in the undercuts and formability of parts. The development of a full 3D cover, applicable to next-generation displays, requires cover glass molding technology with a curvature exceeding 90 degrees. Here, a mold design and molding process, which addresses the current limitations by dividing the existing glass molding press (GMP) process into two stages, is proposed. The bending geometry of the glass prepared on the basis of the proposed mold design plan during single-step compression forming and two-step compression forming was predicted using commercial analysis software. A molding product with a curvature radius of 2.5 mm and an angle of curvature of 138.9 degrees was produced when process conditions with bending by up to 180 degrees with no damage were applied during actual forming experiments. Further research on annealing and cooling processes of GMP is expected to enable the design and process implementation to manufacture curved glass with a single curvature of at least 90 degrees and multiple curvatures.

Automated summary

This study proposes a mold design and molding process that improves the design and forming process of curved displays by dividing the existing glass molding press (GMP) process into two stages. Experimental results show that with appropriate process conditions applied during actual forming experiments, it is possible to produce molded products with a curvature radius of 2.5 mm and an angle of curvature of 138.9 degrees. Further research is expected to enable the design and forming of curved glass with at least 90 degrees of curvature and multiple curvatures.