Bridgestone to introduce Fuel-Efficient Tire for Passenger Cars 'ECOPIA EP100'

Tokyo (October 23, 2007) -- Bridgestone Corporation is pleased to announce the new ECOPIA EP100 tire for passenger cars. The tires will boast an outstanding braking performance in wet conditions in level with the B'STYLE EX tire as well as a 30% reduction in rolling resistance. The tire will go on sale from April 1, 2008 in the sizes 195/55R16, 185/65R15 and 195/65R15, with plans to expand range in a stepwise manner. Prices are all set at the manufacturer's recommended retail price.

The Bridgestone Group formulated its environmental philosophy in 2002. With the environment positioned as a priority management theme, Bridgestone planning to pursue diversity in environmental management activities across all business domains.

One area of focus is the reduction of carbon dioxide emissions, a topic of debate around the world at the moment. In calculating carbon dioxide emissions at each stage of the tire lifecycle, from raw materials to disposal, it was discovered that 87%*1 of total emissions occur during the usage stage. Bridgestone has developed tires with less rolling resistance which will reduce carbon dioxide emissions. This will significantly contribute to environmental preservation on a global scale.

The ECOPIA EP100 employs the ECOPIA compound (a new top rubber) which applies Bridgestone's unique materials technology NanoPro-Tech*2 to reduce rolling resistance. Comparing the ECOPIA EP100 with the B'STYLE EX, rolling resistance is cut down 30%, meaning the new tire boasts the least rolling resistance of any Bridgestone tire on the domestic market. In addition, the tread pattern has rib-linked blocks and high-angle lugs for outstanding braking performance in wet conditions at a level equivalent to the B'STYLE EX.

The development of ECOPIA EP100 is a representation of the Bridgestone Groups' eco-global management efforts. The Bridgestone Group aims to be a global company which is proud of its contribution to the environment by pursuing even greater diversity in environmental management activities across all business domains.

*1. Data source: Japan Rubber Manufacturers Association, Carbon dioxide emissions calculated at each stage of the lifecycle of the passenger car tire 185/70R14.
*2. NanoPro-Tech (Nanostructure-Oriented Properties Control Technology) us the name for the technology which draws out the characteristics required to control the microstructure of materials through molecular design. The technology was announced in July 2006, and was first employed in the BLIZZAK REVO2 winter tire for passenger cars which was released in September 2006. It has also been employed in the ECOPIA M891 II fuel-efficient tire for trucks and buses, which was released in March this year. The NanoPro-Tech is now one of Bridgestone's core technologies.
Product Name ECOPIA EP100

1. Technologies Employed and Product Characteristics
(1) Use of ECOPIA compound
The microstructure of the end-functionalized polymer which is controlled by NanoPro-Tech, fuses with the carbon molecules. This helps to suppress energy loss when a tire is rotating, which leads to reduction of rolling resistance.

(2) Use of new tread pattern
Use of new tread pattern

A. Rib-linked blocks
The blocks and ribs are nestled close together to enhance the rigidity of the block. Making the ground contact pressure of the block uniform during braking provides excellent braking performance.
Comparison of Ground Contact Pressure Distribution

B. High-angle lugs
The angular lugs (side grooves) are positioned at the center of the tread which will evenly distribute dynamic force on the tire surface (part of the tire in contact with the road) when braking.

C. 3D cut ribs
The ribs are cut on an angle at the base of the groove to ensure the pattern remains rigid. This provides power in a lateral direction across the tire.
3D cut ribs

D. Silent AC block
The use of 3D curves on the surface of the block suppresses noise generated when the block is in contact with the road.
Silent AC block

(3) Use of new sidewall rubber
The tire employs a new type of rubber on the sidewall to reduce energy loss caused by the rolling motion. Reduction of rolling resistance contributes to better fuel efficiency. Please note that the new rubber is not used on certain tire sizes.
2. Results of Performance Evaluation
(1) Test results for rolling resistance
Test results for rolling resistance

[Test Parameters]
Measurement method Measured using a drum indoors (drag force method)
Tire size 195/65R15 91H
Rim 15 x 6J
Load 4.41kN
Pressure 210kPa
Speed 80km/h

The rolling resistance coefficient (RRC) results were as follows. EP100: 74.0 x 10-4, B'STYLE EX: 105.6 x 10-4
* More detailed data regarding the above test parameters has been submitted to the Tire Trade Fair council.
* The amount of rolling resistance reduced is not proportional to the improvement in fuel efficiency.
* Rolling resistance measurements differ depending on tire size and other test parameters.
(2) Test results for braking in wet conditions
Test results for braking in wet conditions

[Test parameters]
Test location Asphalt road, Bridgestone proving ground
Driver Data from test course driver
Measurement method Measure braking distance five times and calculate average. Brake test conducted using fifth wheel.
Initial speed 80km/h
Water depth 2mm
Outside temperature 26.5 - 27.0 C
Tire size 195/65R15 91H
Rim 15 x 6J
Car Toyota Prius DAA-NHW20
Pressure Front 230kPa; Rear 220kPa
Passengers Equivalent to two

* More detailed data regarding the above test parameters has been submitted to the Tire Trade Fair council.
* The distance required to stop differs depending on tire size and other test parameters.
eco-Activities This mark expresses the environmental management activities promoted by Bridgestone. The “e” represents the first letter of the word “Ecology”, the cornerstone of these activities. The mark also symbolizes the seeds borne from our eco foundations in the form of a clear sky and growing trees.
Bridgestone Corporation, headquartered in Tokyo, is the world's largest tire and rubber company. In addition to tires for use in wide variety of applications, it manufactures a broad range of diversified products, which include industrial rubber and chemical products and sporting goods. Its products are sold in over 150 nations and territories around the world.