| 摘要 |
PROBLEM TO BE SOLVED: To obtain raw materials for an electromagnetic wave-shielding material which can give a small volume specific resistance without increase in weight and cost. SOLUTION: This electromagnetic wave-shielding material comprises a thermo-plastic resin and carbon fibers with a tensile strength of 4.5-6.5Gpa, and a sheet formed by molding this shielding material has a volume specific resistance R (Ωcm) in the in-plane direction satisfying R<=4.0⊗10<3>×Vf<-2.2> to the content of carbon fiber Vf (in vol.%). In the production, an extruder equipped with a yarn opener and a yarn length controlling mechanism 6 is used to feed continuous carbon fibers with a tensile strength of 4.5-6.5Gpa into the molten thermoplastic resin, while the carbon fibers are opened, cut by the mechanism 6 and dispersed in the molten thermoplastic resin. |
