▎ 摘　　要

NOVELTY - Z-type ferrite (I) is new. USE - Z-type ferrite for radio wave absorber composition and radio wave absorption sheet (all claimed). ADVANTAGE - The single-phase Z-type ferrite can be synthesized by a solid-phase method in air without heat treatment atmosphere control. The Z-type ferrite having plate-like crystal grains is uniformly dispersed without precipitation or agglomeration in the composition, and can be easily manufactured into a radio wave absorber sheet or film. The radio wave absorption sheet has excellent absorption capacity in the GHz band, particularly in the 1-18 GHz band. DETAILED DESCRIPTION - Z-type ferrite of formula Sr3Co2-xMxFe24-dO41 (I) is new. x=0-1; d=0-1.5; and M=Ni or Mn. INDEPENDENT CLAIMS are included for: (1) radio wave absorber composition comprising the Z-type ferrite (I); and (2) radio wave absorption sheet comprising radio wave absorption layer and metal layer disposed on the radio wave absorbing layer, where radio wave absorbing layer includes the Z-type ferrite and a binder.