Abstract: An apparatus may include an ultrasonic sensor stack, a foldable display stack and a transmission enhancement layer. The foldable display stack may include a display stiffener and display stack layers. The display stack layers may form one or more display stack resonators configured to enhance ultrasonic waves transmitted by the ultrasonic sensor stack in a first ultrasonic frequency range. In some implementations, a transmission enhancement resonator may include the display stiffener and the transmission enhancement layer. In some examples, the transmission enhancement resonator may include at least a portion of the ultrasonic sensor stack. The transmission enhancement resonator may be configured to enhance the ultrasonic waves transmitted by the ultrasonic sensor stack in the first ultrasonic frequency range.

Abstract: Described herein is a foamable powder-based composition, comprising: (a) at least one powder-based polymer in an amount of no less than 8% by weight, based on the total weight of the composition, (b) at least one plurality of expandable microspheres in an amount of no less than 15% by weight, based on the total weight of the composition, and (c) optionally at least one filler, wherein the plurality of expandable microspheres in the composition expands when heating; and wherein the composition has a water content of no more than 3% by weight based on the total weight of the composition.

Abstract: Aqueous dispersions and uses for the same. The aqueous dispersion includes a component (a) of one or more ethylene-vinyl ester copolymers and a component (b) of one or more protective colloids. The aqueous dispersion may optionally a component (c1) of one or more nonionic surfactants and/or a component (c2) of one or more ionic surfactants. Where a total amount of the component (b) is less than or equal to 2.2 pphm, preferably between 1-2.2 pphm, or more preferably 1.8 pphm. Additionally, where a total amount of the component (c1) and the component (c2) is less than 0.1 pphm, preferably less than or equal to 0.01 pphm.