US Patent 10293725 Seat support layer assembly

A seat back assembly and method of manufacture is provided. The seat back includes a foam cushion layer. A support sub-assembly is formed including a rigid support layer with a plurality of cavities and channels defined on a rear surface for receiving components and a generally smooth front surface. At least one component is retained in one of the cavities and a second component is secured on the front surface of the support layer. A trim material covers the cushion layer and secures the sub-assembly to the seat back.