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US4398582A Expired / Lapsed US ⏱️ 0.0 years remaining

Pneumatic tire

Assignee: Bridgestone Corp
•
Filing: 1981-05-05
•
Granted: 1983-08-16
•
Expires: 2001-05-05
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Abstract

Abstract A pneumatic tire having remarkably low rolling resistance and high wet skid resistance without deteriorating the wear resistance is obtained by using in at least the ground-contact area of its tread, a rubber composition consisting essentially of 100 parts by weight of a mixed elastomer and 40-80 parts by weight of carbon black, the mixed elastomer consisting of 10-60 parts by weight of a solution-polymerized styrene-butadiene copolymer rubber having a bonded styrene content of 5-30% by weight and a trans-1,4 content in butadiene unit of not more than 45% by weight; 10-50 parts by weight of an emulsion-polymerized styrene-butadiene copolymer rubber having a bonded styrene content of 30-50% by weight; and 0-80 parts by weight of at least one rubber having a glass transition temperature of not higher than -50° C., which is selected from the group consisting of natural rubber, synthetic polyisoprene rubber, polybutadiene rubber and an emulsion polymerized styrene-butadiene copolymer rubber having a bonded styrene content of 18-28% by weight. The use of carbon black having a specific surface area of 85-95 m 2 /g, a dibutyl phthalate absorption value of 100-110 ml/100 g, a tinting strength of 95-105 and a half value width of at least 180 mμ in the size distribution curve of the aggregates is particularly effective for lowering the rolling resistance.

Inventors

  • 👤 Kazuaki Yuto
  • 👤 Toru Oniki
  • 👤 Nobumasa Ikeda
  • 👤 Itsuo Miyake

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 17:27
CPC Classifications
C; C08; C08L; C08L7/00; B; B60; B60C; B60C1/00; B60C1/0016; C08K; C08K3/00; C08K3/02; C08K3/04; C08L9/00; C08L9/06; C08L9/08; Y; Y02; Y02T; Y02T10/00; Y02T10/80; Y02T10/86

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 212 words
A pneumatic tire having a tread, at least the ground-contact area of which is formed of a rubber composition consisting essentially of 100 parts by weight of a mixed elastomer and 40-80 parts by weight of furnace carbon black, said mixed elastomer consisting of 10-60 parts by weight of a solution-polymerized styrene-butadiene copolymer rubber having a bonded styrene content of 5-30% by weight and a trans-1,4 bond content in the butadiene unit of not more than 45% by weight, 10-50 parts by weight of an emulsion-polymerized styrene-butadiene copolymer rubber having a bonded styrene content of 30-50% by weight, and 0-80 parts by weight of at least one rubber having a glass transition temperature Tg of not higher than -50° C., which is selected from the group consisting of natural rubber, synthetic polyisoprene rubber, polybutadiene rubber and an emulsion-polymerized styrene-butadiene copolymer rubber having a bonded styrene content of 18-28% by weight; and said furnace carbon black having a specific surface area (N 2 SA) of 85-95 m 2 /g measured by the nitrogen adsorption method, a dibutyl phthalate absorption value (24M4 DBP) of 100-110 ml/100 g, a tinting strength (TINT) of 95-105 and a half value width (ΔD 50 (ST)) of at least 180 mμ in the size distribution curve of the aggregates.
Claim 2
Dependent Claim 212 words
A pneumatic tire having a tread, at least the ground-contact area of which is formed of a rubber composition consisting essentially of 100 parts by weight of a mixed elastomer and 40-80 parts by weight of furnace carbon black, said mixed elastomer consisting of 10-60 parts by weight of a solution-polymerized styrene-butadiene copolymer rubber having a bonded styrene content of 5-30% by weight and a trans-1,4 bond content in the butadiene unit of not more than 45% by weight, 10-50 parts by weight of an emulsion-polymerized styrene-butadiene copolymer rubber having a bonded styrene content of 30-50% by weight, and 0-80 parts by weight of at least one rubber having a glass transition temperature Tg of not higher than -50° C., which is selected from the group consisting of natural rubber, synthetic polyisoprene rubber, polybutadiene rubber and an emulsion-polymerized styrene-butadiene copolymer rubber having a bonded styrene content of 18-28% by weight; and said furnace carbon black having a specific surface area (N 2 SA) of 85-95 m 2 /g measured by the nitrogen adsorption method, a dibutyl phthalate absorption value (24M4 DBP) of 100-110 ml/100 g, a tinting strength (TINT) of 95-105 and a half value width (ΔD 50 (ST)) of at least 180 mμ in the size distribution curve of the aggregates.
Claim 3
Dependent Claim 31 words
A pneumatic tire according to claim 1, wherein the mixed elastomer contains 10-60 parts by weight of the rubber having a glass transition temperature Tg of not higher than -50° C.
Claim 4
Dependent Claim 52 words
A pneumatic tire according to claim 1, wherein the carbon black is furnace carbon black having a specific surface area (N 2 SA) of 85-92 m 2 /g measured by the nitrogen adsorption method, a dibutyl phthalate absorption value (24M4 DBP) of 103-110 ml/100 g and a tinting strength (TINT) of 98-105.

References Cited (Backward Citations)

US3491052A Cited
US3304281A Cited
US3596697A Cited
US3736312A Cited
US4259218A Cited
US4360627A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-08-15 1987-02-14 1987-08-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-08-15 1991-02-14 1991-08-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-08-15 1995-02-14 1995-08-16 $7700.00 Window Closed / Lapsed

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