Apple updates their invention for a new Protective Layer for Foldable Displays that's designed to Resist Cracking at the Fold Mark
Today the US Patent & Trademark Office published a continuation patent application from Apple that relates to preventing the potential problem of folding devices, like a smartphone or tablet, from cracking in the fold area. Apple's invention covers the use of a protective cover layer structure that could make the display crack resistant and it's this very core process that Apple's continuation patent has now updated.
Apple's original patent application that surfaced a year ago describes display modules and protective cover layer structures that may be implemented in curved, flexible, conformable and foldable display modules, and in particular with curved, flexible, conformable and foldable display panels.
Apple's patent FIG. 1 below is a schematic isometric view illustration of a protective cover layer; FIG. 2 is a schematic cross-sectional side view illustration of a bent protective cover layer.
Apple notes that typically, glass fracture initiates from the presence of micro-cracks. The hardcoat layer #104 in accordance with embodiments may fill pre-existing micro-cracks and also make it harder to initiate a crack.
Furthermore, the hardcoat layer may be engineered to have a sufficiently high hardness and tensile strength to function as an exterior protective coating for the electronic device, while being able to withstand more strain before fracture compared to the transparent support substrate #102. Thus, the hardcoat layer is sufficiently durable for high puncture and scratch resistance.
Apple's patent FIG. 4A above is a schematic top view illustration of crack propagation in a scratched transparent support substrate; FIG. 4B is a schematic top view illustration of crack propagation in a scratched transparent support substrate with hardcoat layer.
Apple's patent FIGS. 12A-12B above are schematic isometric view illustrations of an electronic device #1200 such as an iPhone. The display panel #150 and protective cover layer #100 may be curved, flexible, conformable and/or foldable. Apple's patent FIG. 12A illustrates an outward bending application, while FIG. 12B illustrates an inward bending application.
Being a continuation patent, Apple is updating their patent claims to strengthen their invention. The main addition to their patent claims revolves around "a particle filler within a polymer matrix." The following are new claims on this topic:
Patent Claim #1: An electronic device comprising: a display panel; a protective cover layer over the display panel, wherein the protective cover layer includes a transparent support substrate and a hardcoat layer covering an exterior facing surface of the transparent support substrate; and wherein the transparent support substrate is formed of a material selected from the group consisting of glass and sapphire, and the hardcoat layer includes a particle filler within a polymer matrix.
Patent Claim #7: The electronic device of claim 1, wherein the particle filler includes ceramic particles selected from the group consisting of Al.sub.2O.sub.3, MgAlO.sub.4, SiAlON, AlON, and ZrO.sub.2.
Patent Claim #16: The electronic device of claim 14, further comprising a particle filler dispersed in the polymer matrix.
Patent Claim #17: The electronic device of claim 16, wherein a concentration of the particle filler is higher nearest the transparent support substrate and lower nearest the outer surface of the hardcoat layer.
Apple's continuation patent 20210096595 was filed in October 2020 and published today by the U.S. Patent and Trademark Office.
Considering that this is a patent application, the timing of such a product to market is unknown at this time.