Patent ID: 8998337
Filing Date: 2015-04-07
Classification: A47C

Abstract:
1. A backrest chair characterized in that a core sheet is formed by attaching a shape retaining material capable of elastic bending deformation to mesh sheets capable of elastic bending deformation, to have an elastic resilience for assuming a backrest shape in a natural state and to be elastically displaceable while maintaining a backrest state by a stretching force in a use situation; that a chair sheet material is formed by providing a buffer sheet to cover a surface of the core sheet which is in the use situation on a back side of a seated person in a seated position; that an upper part of a backrest portion of the chair sheet material is extended to form an extended part capable of supporting a head of the seated person, and when a load of the head of the seated person is applied to the extended part, the extended part can bend and move further rearward than the backrest portion of the chair sheet material due to elasticity of the core sheet; and that the chair sheet material is attached to a chair support frame lower than a seat surface in a state of positioning the core sheet and the buffer sheet on a back and a rear surface of the head of the seated person, and wherein the chair sheet material is characterized in that a cut hole is formed to penetrate the core sheet and the buffer sheet and having a length approximately corresponding to a half of an entire circumference of a seat portion, the backrest chair being constructible by attaching the chair sheet material to the chair support frame by fitting the cut hole on the chair support frame.