| 摘要 |
The present invention provides a magnetic recording medium which can record both digital and analog signals by, e.g., VTR for commercial use and improve their electromagnetic conversion characteristics. A magnetic recording medium comprises a nonmagnetic support, and first and second magnetic layers comprised respectively of magnetic powder (A) and (B), wherein the first and second magnetic layers are formed on the nonmagnetic support in this order, wherein the magnetic powder (A) and (B) have the following characteristics: <tables id="TABLE-US-00001" num="00001"> <table frame="none" colsep="0" rowsep="0"> <tgroup align="left" colsep="0" rowsep="0" cols="3"> <colspec colname="offset" colwidth="21pt" align="left"/> <colspec colname="1" colwidth="112pt" align="left"/> <colspec colname="2" colwidth="84pt" align="left"/> <THEAD> <ROW> <ENTRY/> <entry namest="offset" nameend="2" align="center" rowsep="1"/> </ROW> </THEAD> <TBODY VALIGN="TOP"> <ROW> <ENTRY/> <ENTRY>saturation magnetization sigmas(A)</ENTRY> <ENTRY> 80 to 150 Am<SUP>2</SUP>/kg;</ENTRY> </ROW> <ROW> <ENTRY/> <ENTRY>coercive force Hc(A)</ENTRY> <ENTRY> 90 to 180 kA/m,</ENTRY> </ROW> <ROW> <ENTRY/> <ENTRY>saturation magnetization sigmas(B)</ENTRY> <ENTRY>100 to 200 Am<SUP>2</SUP>/kg,</ENTRY> </ROW> <ROW> <ENTRY/> <ENTRY>coercive force Hc(B)</ENTRY> <ENTRY>100 to 200 kA/m,</ENTRY> </ROW> <ROW> <ENTRY/> <entry namest="offset" nameend="2" align="center" rowsep="1"/> </ROW> </TBODY> </TGROUP> </TABLE> </TABLES> wherein the first and second magnetic layers satisfy the below relationships and have thickness T(A) and T(B) in the below ranges: <?in-line-formulae description="In-line Formulae" end="lead"?>sigmas(A)/sigmas(B)<=1.0,Hc(A)/Hc(B)<=1.0,<?in-line-formulae description="In-line Formulae" end="tail"?> <?in-line-formulae description="In-line Formulae" end="lead"?>1.0 mum<=T(A)<=4.0 mum, 0.01 mum<=T(B)<=0.5 mum.<?in-line-formulae description="In-line Formulae" end="tail"?>
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