| KP Sheet is
a stampable sheet made of glass fiber (GF)
and polypropylene (PP), and has a distinctive
characteristic of expansion in thickness.
To realize light weight and high stiffness
in automotive headliners, the GF content and
arrangement in the thickness direction were
studied with the aim of increasing expansivity.
Although expansivity increases with GF content
and the elastic slope is enhanced by the resulting
increase in sheet thickness, the maximum elastic
slope reaches saturation at a GF content of
50mass% or more. Therefore, the GF arrangement
in the thickness direction is controlled to
improve GF spring back, resulting in a 30%
improvement in expansivity at the same unit
weight. A newly-developed ultra-light product
(UL grade) realizes a high elastic slope of
7.2N/mm at a web unit weight of 800g/m²,
while also displaying excellent moldability
and dimensional stability equal to those of
normal grade KP Sheet, enabling further weight
reduction. |
