Patent US4257468A successfully refreshed from Google Patents.
US4257468A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pneumatic tire having an improved chipping resistant property employing syndiotactic-1,2-polybutadiene in tread rubber
Assignee: Bridgestone Corp
•
Filing: 1979-04-05
•
Granted: 1981-03-24
•
Expires: 1999-04-05
Abstract
Abstract A pneumatic tire having an improved chipping resistant property is disclosed. In the tire, the tread portion is formed with a vulcanizate of a rubber composition comprising 3-40 parts by weight of short fibers of syndiotactic-1,2-polybutadiene, 30-100 parts by weight of carbon black and 0.2-5 parts by weight of a p-phenylenediamine type antioxidant, on a basis of 100 parts by weight of a rubber selected from natural rubber, synthetic rubber and a blend thereof in an optional blending ratio.
Inventors
- 👤 Masaki Ogawa
- 👤 Tamio Araki
- 👤 Shinji Yamamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:24
CPC Classifications
B; B60; B60C; B60C11/00; B60C11/14; B60C1/00; B60C1/0016; Y; Y10; Y10S; Y10S152/00; Y10S152/04; Y10T; Y10T152/00; Y10T152/10; Y10T152/10495; Y10T152/10513
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
106 words
A pneumatic tire having an improved chipping resistant property, comprising a tread portion formed from a vulcanizate of a rubber composition comprising; (a) 3-40 parts by weight of preformed short fibers of syndiotactic-1,2-polybutadiene having a maximum diameter of not more than 10μ and an average diameter of less than 1μ, (b) 30-100 parts by weight of carbon black having an iodine adsorption value of not less than 76 mg/g and (c) 0.2-5 parts by weight of a p-phenylenediamine type antioxidant, on a basis of 100 parts by weight of (d) a rubber selected from natural rubbers, synthetic rubbers and blends thereof in an optional blending ratio.
Claim 2
Dependent Claim
106 words
A pneumatic tire having an improved chipping resistant property, comprising a tread portion formed from a vulcanizate of a rubber composition comprising; (a) 3-40 parts by weight of preformed short fibers of syndiotactic-1,2-polybutadiene having a maximum diameter of not more than 10μ and an average diameter of less than 1μ, (b) 30-100 parts by weight of carbon black having an iodine adsorption value of not less than 76 mg/g and (c) 0.2-5 parts by weight of a p-phenylenediamine type antioxidant, on a basis of 100 parts by weight of (d) a rubber selected from natural rubbers, synthetic rubbers and blends thereof in an optional blending ratio.
Claim 3
Dependent Claim
26 words
A pneumatic tire as claimed in claim 1, wherein each of said short fibers of syndiotactic-1,2-polybutadiene has a 1,2-structure unit content of not less than 80%.
Claim 4
Dependent Claim
26 words
A pneumatic tire as claimed in claim 1, wherein each of said short fibers of syndiotactic-1,2-polybutadiene has a melting point of not less than 190° C.
Claim 5
Dependent Claim
22 words
A pneumatic tire as claimed in claim 1, wherein the amount of said short fibers of syndiotactic-1,2-polybutadiene is 5-20 parts by weight.
Claim 6
Dependent Claim
27 words
A pneumatic tire as claimed in claim 1, wherein said p-phenylenediamine type antioxidant is selected from the group consisting of N-phenyl-N'-isopropyl-p-phenylenediamine, N,N'-diphenyl-p-phenylenediamine, N-phenyl-N'-(2,4-dimethyl)butyl-p-phenylenediamine, N,N'-di-2-naphthyl-p-phenylenediamine and mixtures thereof.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-03-23 | 1984-09-22 | 1985-03-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-23 | 1988-09-22 | 1989-03-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-23 | 1992-09-22 | 1993-03-24 | $7700.00 | Window Closed / Lapsed |