| 摘要 |
PROBLEM TO BE SOLVED: To provide a back layer of a vehicle ceiling material, configured to have superior sound insulation function that reduces vibration noise of a harness during traveling, and to enable simple-step manufacturing.SOLUTION: A back layer 1 of a vehicle ceiling material includes: an expansion layer 6 including a film-like capsule-added polypropylene, which is formed by adding a thermally expandable microcapsule to polypropylene of block copolymer or homopolymer at a predetermined mixing ratio, and containing air bubble formed by expansion of the thermally expandable microcapsule; and a polypropylene layer 7 laminated on one surface 6b of the expansion layer 6 and formed by shaping polypropylene in a film shape. |
