| 摘要 |
PURPOSE:To obtain an electrically conductive urethane foam improved in fixing properties and dispersion of an electrically conductive material by dispersing a water-dispersible binder and a nonionic surfactant having a low HLB in a dispersion of fine electrically conductive powder and fine mica powder and impregnating a urethane foam therewith. CONSTITUTION:The objective urethane foam obtained by dispersing (B) a water- dispersible binder, (C) a nonionic surfactant having 8-11 HLB and preferably (D) a rust preventive agent in (A) a dispersion prepared by dispersing fine electrically conductive powder and fine mica powder expressed by the formula [A is K, Na or Ca; B and C are Fe(II), Fe(III), Mn, Al, Mg or V; D is Si or Al] in water using a nonionic surfactant having >=12 HLB, preparing an electrically conductive treating liquid and fixing the resultant liquid to a urethane foam. Thereby, balance between controllability and hardly falling off properties of IC lead frames is suitably regulated. |
