MOORESVILLE, N.C. — A dyeing process developed by Burlington Denim is taking the stone out of stone washing.

The proprietary technology, which has been adopted to a line of denim fabrics called Stone Free, allows indigo shades to break down 50 percent faster in the laundering cycle — without the use of stones and chemicals — according to company executives. Stone Free fabrics, said Burlington executives, are also designed to reduce imperfects, lower costs and substantially lessen the amount of effluence emitted into the environment during the wash cycle.

Traditional stonewashing is done with a pumice stone, a lightweight, volcanic rock. The pumice rubs against the fabric in the washing machine, causing an abraded look. Stone Free has taken two years to develop at a cost of about $500,000, according to Burlington executives. It is currently available in 14 3/4-ounce, 100 percent cotton denim fabrics. Stone Free-type fabrics for shorts, shirts and sportswear applications, along with denim using a blend of cotton and Hoechst Celanese’s ESP polyester, are in the developmental stages.

“The stonewash look is a leading laundering finish for denim, and we project that look to continue,” said Kathy Barton, Burlington Denim’s vice president of fashion marketing, noting the product is being sampled by Levi Strauss, Lee, Guess and The Gap. Denim using Stone Free will be available to consumers in spring 1995.

Although the process adds from 10 to 15 percent to the price of the fabric, Burlington executives said apparel makers will save money because more products can be made in less time.

Stone Free denim can be used to create the three key looks of stonewashed denim: the classic six-to-eight dip denim, which is dipped by the mill, then washed by the launderer; a classic with bleach look, which is bleached and washed by the launderer, and the destructed look denim, which uses the heaviest washing process.

Achieving the first two looks with Stone Free requires no stones at all. Some stones are needed to achieve the destructed look, said Doug Murphy, a Burlington Denim vice president of marketing, but the stones required are about one-third of those needed in the usual processing, and the time required is cut about 50 percent. In a traditional stonewash process to achieve a destructed look — about three hours — stones are added every hour on average. With Stone Free, they’re only put in once, and the laundering process lasts only 1 1/2 hours, he said.

“The key is that the weight ratio of stones and garments in the destructed look is about 1-to-1,” said Murphy. “But with Stone Free denim, you don’t have to keep adding the stones.”

“We have tested the Stone Free, and it seems the abrasion level is reached faster than regular stonewashing, and it achieves a well-worn finish without the damage,” said Claude Blankiet, co-owner and vice president of American Garment Finishing, a denim finisher and launderer in El Paso, Tex. “It’s not a miracle fabric, but it could develop into a very important one for denim.”

He said it will be interesting to see how many other types of fabrics it can be used for.

Blankiet added that because Stone Free eliminates much of the sludge waste that results from stonewashing, “it will drastically cut the pollution associated with our type of business.”

Murphy, however, said Burlington is not plugging Stone Free as an environmentally friendly fabric, but rather as a process that allows apparel manufacturers and launderers to do things more cleanly, quickly and economically.

“The fact that it reduces pollution is just one of its attributes,” said Murphy, “but it’s not the only one we will emphasize.”

In spite of the push toward Stone Free, Burlington isn’t about to desert denims for traditional stonewashing.

“This is a new way to do things,” Barton said. “We would never convert all of our capacity for Stone Free. There are still a lot of stonewash customers.”

Stone Free apparel fabrics are currently being produced solely at the firm’s Mooresville plant — which is observing its 100th anniversary. However, the process could be duplicated at Burlington’s other denim facilities at Stonewall, Miss., and Hillsville, Va.

“This is not a traditional denim process,” said Ed Teague, a chemist at Burlington for the past 45 years, who lead the team that created Stone Free. Burlington produces in excess of 450 experimental fabrics per year, but fewer than 10 percent ever reach the market.

“In terms of how significant a development this is for the company, it definitely ranks as a high one,” Teague said.

To back its Stone Free fabrics, and to educate its customers, Burlington next week will begin mailing packets of materials for a Save the Stone promotional campaign, a collection of bumper stickers, literature and advertising ideas.

“We need to sell the concept to them, but to do that, we have to educate them,” Barton said.