The Bridgestone Group has announced the goal of reducing tire rolling resistance coefficients by 25%, compared to a 2005 baseline, by 2020, in order to promote a low-carbon society, a key step towards developing a sustainable society. We are working to achieve this goal, including by expanding our line of fuel-efficient tires such as the ECOPIA EP100S. In 2010, we succeeded in reducing rolling resistance coefficients by 3.4%,* compared to a 2005 baseline.

*Based on the weighted average of passenger car, truck and bus tires sold during the year.

Rolling resistance coefficient

Actual calculation

Bridgestone Group's CO₂ Emission Report Independent Review

Bridgestone is also working to expand our products and services that help reduce its environmental impact, including expanding the retread tire solutions business in the global market, launching the AeroBee brand of electronic paper products and expanding associated manufacturing lines, and launching COOLSAFE, a heat-shielding film for architectural glass. By offering these products and services, we are working with customers to achieve a society founded on ecological conservation, resource conservation and reducing carbon emissions to build a sustainable society described in our Environmental Mission Statement.

Developing a new retread tire solutions business

Tire retreading provides an excellent example of tire reuse. Retread tires are manufactured by mill buffing the tread rubber surface on used tires to a predetermined depth, and then bonding new rubber and vulcanizing it so that the tire can be reused. Since everything except the tread rubber (i.e., the entire base tire) can be reused, use of retread tires helps lower consumption of raw materials such as natural rubber and synthetic rubber, which are both produced using petroleum, while at the same time decreasing the number of tires being disposed of.

A new business model: ECO Value Pack

Retreading aircraft tires

Bridgestone has been retreading aircraft tires in Japan since 1955. Today, we provide products and services with outstanding environmental friendliness, safety and value to customers worldwide from a total of five retreading plants located around the world.

Aircraft tires are designed to be retreaded and must meet strict requirements imposed by aircraft manufacturers. Tire treads that have been worn down by repeated takeoffs and landings are retreaded at the Bridgestone Group's plants. Bias tires for use on the main landing gear generally sustain enough wear to require retreading after about 200 takeoffs and landings, although the exact number depends on the model of aircraft. By contrast, radial tires for main gear use usually need to be retreaded after about 350 takeoffs and landings. Bias tires can typically be retreaded up to six times, while radial tires can be retreaded a maximum of three times. Both tire types can be used for a maximum of about 1,400 takeoffs and landings, including use when new.

Aircraft tires to be retreaded undergo tests at each stage of the retreading process, and only those tires that pass a nondestructive final inspection are shipped. In this way, we offer customers retreaded tires that deliver the same level of performance as new tires.

Click here for more information about Bridgestone's aircraft tire service network.

Developing environmental technologies in the tire business

Bridgestone is developing a range of environmental technologies in areas such as tire structure, profile and materials design. We are also actively involved in researching, developing and producing tires and associated systems.

We will focus on developing technologies to achieve our goal of reducing tire rolling resistance by 25%, compared to 2005 values, by 2020, a goal related to CO₂ reduction which we announced in April 2010.

NanoPro-Tech, a technology for controlling the microstructure of rubber molecules

NanoPro-Tech is the name for a critical technology that allows the company to give rubber the required characteristics by controlling material microstructure through such processes as a molecular-level structural design. It was technologies such as NanoPro-Tech that allowed us to successfully resolve the degradation in wet grip and other aspects of safety performance that is typically a byproduct of efforts to reduce rolling resistance.

Today's Bridgestone products that include NanoPro-Tech technology are: ECOPIA EP100S, BLIZZAK REVO GZ and run-flat tires for passenger vehicles, as well as ECOPIA R201 and ECOPIA R221II for trucks and buses.

Cooling fins, a technology that helps reduce run-flat tire weight and improve ride comfort

Cooling fins are a new technology for improving the performance of run-flat tires, which can be driven for a certain distance at a manufacturer-specified speed, even after a puncture causes the tire pressure to drop to zero.

Equipping a vehicle with run-flat tires eliminates the need for the vehicle to carry a spare tire, which generally reduces its environmental impact by saving resources and improving fuel economy as a result of the lighter vehicle weight. However, as engineers have worked to improve the run-flat endurance of sidewall-reinforced run-flat tires*, they have found that they needed to make changes to limit heat generation caused by deformation of the sidewalls due to flexing when the tires were driven with no air pressure. Cooling fins are an innovative new technology for cooling the tires by inducing turbulent airflow by means of radial-axis protrusions placed along the sidewall.

This technology has simplified the development of run-flat tires in sizes with large cross-sectional profiles suitable for use by some SUVs, minivans and large passenger vehicles. Additionally, the ability to reduce the thickness of the sidewall-reinforcing rubber allows further weight reductions and improvements in ride comfort.

*Run-flat tires are designed so that sidewall-reinforcing rubber helps support the tire load in the event of a loss in air pressure.

RRR, an advanced radial structure for aircraft tires

Bridgestone uses an advanced radial structure known as RRR (Revolutionarily Reinforced Radial) in its aircraft tires. In addition to delivering a high level of safety due to its use of high-elasticity, high-strength fibers and a new belt structure using stronger, more elastic cord, RRR lowers fuel consumption by reducing tire weight by 7% to 10%. The new design helps save energy while increasing the number of takeoffs and landings that the tire can endure through improved wear resistance.

In October 2008, Boeing selected tires featuring this new technology for use on its 777-300ER aircraft. By replacing the aircraft's total of 12 main gear tires-six on each side-with RRR tires, the company was able to reduce the aircraft's gross weight by about 80 kilograms^*.

*Based on a comparison with previous Bridgestone tires.