Multi-piece solid golf ball

A multi-piece solid golf ball comprising a core, an envelope layer, an intermediate layer and a cover, wherein the envelope layer is formed into two layers—an inner envelope layer and an outer envelope layer;

• the sphere obtained by encasing the core with the inner envelope layer (inner envelope layer-encased sphere), the sphere obtained by encasing the inner envelope layer-encased sphere with the outer envelope layer (outer envelope layer-encased sphere), the sphere obtained by encasing the outer envelope layer-encased sphere with the intermediate layer (intermediate layer-encased sphere) and the ball have respective surface hardnesses which together satisfy the following relationship:
• surface hardness of inner envelope layer-encased sphere<surface hardness of outer envelope layer-encased sphere<surface hardness of intermediate layer-encased sphere<surface hardness of ball;
• and the inner envelope layer or outer envelope layer is formed primarily of an elastomer;
• and
• wherein the core has a hardness profile in which, letting Cc be the Shore C hardness at a center of the core, Cs be the Shore C hardness at a surface of the core, CM be the Shore C hardness at a midpoint M between the center and surface of the core, CM+2.5, CM+5.0 and CM+7.5 be the respective Shore C hardnesses at positions 2.5 mm, 5.0 mm and 7.5 mm from the midpoint M toward the core surface and CM−2.5, CM−5.0 and CM−7.5 be the respective Shore C hardnesses at positions 2.5 mm, 5.0 mm and 7.5 mm from the midpoint M toward the core center, the following surface areas A to F:
• surface area A:
• ½×2.5×(CM−5.0−CM−7.5)
• surface area B:
• ½×2.5×(CM−2.5−CM−5.0)
• surface area C:
• ½×2.5×(CM−CM−2.5)
• surface area D:
• ½×2.5×(CM+2.5−CM)
• surface area E:
• ½×2.5×(CM+5−CM+2.5)
• surface area F:
• ½×2.5×(CM+7.5−CM+5)
• satisfy the two conditions
• (surface area D+surface area E+surface area F)−(surface area A+surface area B+surface area C)>0, and
• (surface area D+surface area E)−(surface area A+surface area B+surface area C)≥0.