| abstract |
There is provided a polyamide composition for an LED reflection plate, including a polyamide (A), a titanium oxide (B), a magnesium oxide (C), a phenolic antioxidant (D), and a phosphorus-containing antioxidant (E), wherein the polyamide (A) is a polyamide having a dicarboxylic acid unit comprising 50% by mol or more of 1,4-cyclohexanedicarboxylic acid unit and a diamine unit and having a melting point of 280°C or higher; the phenolic antioxidant (D) does not have 4 or more phenol structures in its molecule; and the phosphorus-containing antioxidant (E) has 3 or more predetermined structures represented by the formula (1) in its molecule, wherein the content of the titanium oxide (B) is 10 to 100 parts by mass, the content of the magnesium oxide (C) is 0.50 to 15.0 parts by mass, and the content of the phenolic antioxidant (D) is 0.10 to 0.80 part by mass, with respect to 100 parts by mass of the polyamide (A); and the content of the phosphorus-containing antioxidant (E) satisfies the following expression (I): 0.25 ¤ mass ratio D component/ E component ¤ 3.0 There are also provided a reflection plate obtained by molding the composition, and a light-emitting device having the reflection plate. |