| 摘要 |
PROBLEM TO BE SOLVED: To provide a reflective sheet having a high reflectance produced by using a porous membrane which contains a large amount of voids. SOLUTION: The reflective sheet 3 is produced by laminating a porous membrane and a sheet metal 4, wherein the porous membrane consists of a composition which contains a polyolefine and inactive fine particles, has independent or continuous voids by which having a porosity of 70-95 vol.%, and R obtained by the following formula (1): R=(reflection factor)/(solid content ratio), using a total solid content ratio of the polyolefine and the inactive fine particles constituting the porous membrane and a reflection factor of the porous membrane is at least 3.0. In the formula, the reflection factor (%) is a reflection factor at the wavelength of 550 nm, the solid content ratio is represented by formula; solid content ratio (%)=100-porosity (%), and porosity (%)=(ρ0-ρ)/ρ0×100, (ρ0: theoretical density from the total of the polyolefine and the inactive fine particles,ρ: apparent density of the porous membrane). COPYRIGHT: (C)2009,JPO&INPIT |
