| 摘要 |
PURPOSE:To obtain the title flame retardant cable having excellent flame retardancy and mechanical characteristic by using a material contg. glass having a specified softening point along with a non-halogen flame retardant, as the sheath. CONSTITUTION:The sheath is formed with the material contg. 100pts.wt. polyolefin polymer, 40-150pts.wt. non-halogen flame retardant, and at least 2pts.wt. glass powder having a softening point lower than the thermal decomposition temp. of the polymer. The glass powder having a low softening point is appropriately used, and the softening point must be lower than the thermal decomposition temp. of the polyolefin polymer to be used in the sheathing material. When the cable is placed in a combustion atmosphere, glass is deposited on the surface of the sheath at a temp. lower than the thermal decomposition temp. of the polyolefin polymer, and an inert and incombustible surface layer is formed. The surface layer has the function of protecting the cable from oxygen and flame. As a result, a sufficient flame retarding effect can be exhibited without using a halogen-based flame retardant. |
