Sughrue, Mion, Zinn, Macpeak & Seas
Rubber composition
 A rubber composition contains 100 parts by weight of natural rubber and/or a diene type synthetic rubber and 20-70 parts by weight of carbon black having the following characteristics: PA1 (1) N.sub.2 SA: 70.about.145 m.sup.2 /gr; PA1 (2) DBP: 160.about.200 ml/100gr; PA1 (3) 24M4DBP: 130.about.150 ml/100gr; PA1 (4) DBP-24M4DBP=.DELTA.DBP.ltoreq.1.25.times.DBP-172.5; PA1 (5) N.sub.2 SA/IA: 1.1.about.1.4; and PA1 (6) .DELTA.D.sub.50 /dst: 0.50.about.0.80. 
Bridgestone Corporation
C C C C
C01P C08K C01P C09C
additional inventional additional inventional
Masayuki Hiroshi Tomohiro
Ohashi Yamada Kusano