Yokohama develops auto hose for use with next-generation refrigerant

TOKYO—Yokohama Rubber Co. Ltd. has introduced a line of hoses that offer compatibility with HFO-1234yf, an automotive air-conditioning refrigerant gaining widespread use in the U.S. because it contributes less to global warming than the standard HFC-134a refrigerant.

While HFO-1234yf has a global warming potential rating of 4—compared to 1,430 for HFC-134a—it can decompose over time, releasing acids that corrode the resin on the inner surface-layer of the hose. To combat this decomposition, Yokohama has taken steps to improve the resin material, making use of company-developed polyamide resin containing an acid-acceptor.

Yokohama said its new hose structure also employs an inner rubber with improved adhesion to the resin that prevents direct contact between the refrigerant and resin layer.

In Japan, the firm has applied for patents for a compound material used in the inner rubber layer of the hose, and has plans to develop a full range of these barrier-type hoses.

The Tokyo-based company said its ACBR series of high- and low-pressure hoses have been selected for use in the 2018 Jeep Wrangler and 2018 Jeep Compass.