Today the U.S. Patent and Trademark Office officially granted Apple a patent that relates to providing future devices such as an iPhone, iPad or MacBook with an abrasion-resistant back panel that could be glass or metal.

In Apple's patent background they noted that electronic devices, especially portable electronic devices such as handheld mobile phones, tablet computers and notebooks could experience contact with various surfaces that leads to marring, or abrasion, of the surface of the device. Housing materials for such devices may have different combinations of properties relating to strength, appearance, abrasion resistance, electromagnetic shielding, and the like. For example, metal housings may be strong and relatively scratch resistant, but may provide undesirable electromagnetic shielding. Plastic may have better electromagnetic shielding properties than metal, but may be less scratch or abrasion-resistant. Other materials may provide different combinations of pr A housing of an electronic device includes a substrate defining an external surface and internal surface of the housing, at least one sidewall extending from the substrate, and abrasion-resistant members at least partly embedded in the substrate and extending beyond the external surface.

Apple Patent: Spatial Composites

Apple's patent covers abrasion-resistant members that are formed from metal or ceramic. The substrate may comprise a moldable matrix. The abrasion-resistant members are harder than the moldable matrix. An average distance between the adjacent abrasion-resistant members is between about 10 and 100 microns.

The abrasion-resistant members each may have a faceted surface. The abrasion-resistant members may be configured to reflect light at an angle. The substrate may have a Young's modulus greater than, or equal to about 5 GPa. The beads may have a diameter between 0.5 and 5 mm.

A housing of an electronic device including a housing structure defining an external surface and internal surface of the housing, at least one sidewall extending from the external surface, and beads having interlocking features and being at least partially embedded in the housing structure, such that the interlocking features mechanically engage the housing structure and portions of the beads protrude above the external surface.

The beads are distributed in a regular pattern over a first portion of the external surface. A second portion of the external surface may be substantially free of beads. The second portion of the external surface corresponds to a location of an antenna within the housing.

The housing structure may comprise a moldable material. The beads may comprise a hard material embedded within at least a portion of the moldable material. A hardness of the hard material is greater than a hardness of the moldable material.

The moldable material may be a polymer. The moldable material may be an amorphous metal. The beads may each have a faceted surface, such that a portion of the housing structure having the beads at least partially embedded therein produces a specular reflection. The interlocking features include at least one of through-holes, flanges, or indentations. The interlocking features may comprise connecting elements joining at least a subset of the beads to one another. The subset of the beads and the connecting elements are a monolithic structure.

A method for producing an abrasion-resistant housing of an electronic device including disposing abrasion-resistant components with interlocking structures in a mold cavity having a shape corresponding to a housing of an electronic device, introducing a moldable material into the mold cavity, thereby at least partially encapsulating the interlocking structures while maintaining a portion of the abrasion-resistant components outside of the moldable material, and curing the moldable material, thereby engaging the cured moldable material with the interlocking structures and forming the housing. The interlocking structures may include at least one of holes, meshes, swages, and undercuts.

Apple's patent FIG. 2A below illustrates the back glass panel of an iPhone using 'Spatial Composites,' which is described as having embedded abrasion-resistant members; FIG. 2C shows a cross-sectional view of a housing of a device showing example abrasion-resistant members embedded in the housing of the electronic device.

Apple's patent FIG. 4A above shows a cross-sectional view of a device  illustrating an example of a substantially spherical abrasion-resistant member with an interlocking structure embedded in a substrate.

Apple's patent FIG. 7A above illustrates a three-sided pyramidal faceted abrasion-resistant structure and the substrate surface; FIG. 7B illustrates a four-sided pyramidal faceted abrasion-resistant structure and the substrate surface; and FIG. 7C illustrates a dodecahedron- or icosahedron-shaped abrasion-resistant member may be embedded at least partially in the substrate.

Apple's patent FIG. 8 above shows an example process of forming an electronic housing.

For more details, review Apple's granted patent 11678445. The lead inventor listed on the patent is Chris Prest: Senior Director, Materials Engineering & Product Design (17 years at Apple).