| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To enhance reliability and productivity of a spark plug, even if its diameter is reduced, by creating a resistance-forming glass constituent capable of fully suppressing the occurrence of high-frequency noise electric waves. <P>SOLUTION: A resistance-forming material includes coarse-grained glass powder and coarse-grained ceramic filler, wherein (1) the coarse-grained glass powder contains 35 to 60 mass% of SiO<SB>2</SB>, 25 to 55 mass% of B<SB>2</SB>O<SB>3</SB>, 1 to 20 mass% of Li<SB>2</SB>O+Na<SB>2</SB>O+K<SB>2</SB>O, 0 to 35 mass% of MgO+CaO+SrO+BaO and 0 to 14 mass% of BaO, as glass composition, (2) the average grain diameter D<SB>50</SB>of the coarse-grained ceramic filler is 50 to 300μm, and (3) the content of the coarse-grained ceramic filler is 1 to 55 mass%. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
