| 摘要 |
PURPOSE:To provide the original feed belt consisting of a cover resin layer and core canvass with excellent fire retardance by incorporating a phosphoric acid system chlorine compd. into the cover resin layer of the belt. CONSTITUTION:This original feed bent consists of the cover resin layer 2 and the core canvass 1 and at least its cover resin layer contains the phosphoric acid system chlorine compd. The phosphoric acid (orthophosphoric acid) is thermally decomposed to polymetaphosphoric acid. Namely, the phosphoric acid (H3PO4) metaphosphoric acid (HOP3) the polymetaphosphoric acid (PnO3n)<n->. This polymetaphosphoric acid is a strong acid and is a strong dehydrating agent. More particularly, polyurethane and polyester contg. hydroxyl groups are accelerated in formation of carbides by this strong acid. The non-volatile phosphoric acid compd. acts as a freezing agent for carbon residues and oxygen is shielded. The chlorine compd. releases gaseous chlorine, thereby shutting off the oxygen and suppressing a combustion reaction. |
