EASTMAN
BUSINESS
sess cleaning ability. “We use the sprayand-pray method,” they heard from one potential customer. So de Wit decided to turn a device used to test coatings into a scrub machine that would test a solvent’s cleaning ability in a reproducible manner. SCRUBINATOR
Using their homemade scrub machine, Eastman researchers put their new solvent through the paces.
ARMED WITH HIS new machine, de Wit
put butyl 3-hydroxybutyrate through the paces, and it shined. For example, in a tar removal test, a neutral-pH cleaner containing 2% of the new solvent was superior to cleaners with low-VOC solvents such as dipropylene glycol n-propyl ether. It even Seeing a performance gap, Eastman scientists beat cleaners with VOCs like ethylene glyinvent a new CLEANING SOLVENT col monobutyl ether, according to Eastman. The testing proved that the solvent IF YOUR ALL-PURPOSE spray cleaner Eastman began the search for an effecworks, but the Eastman developers also doesn’t seem to work quite as well as it tive but environmentally friendly solvent wanted customers to know that it’s safe, once did, it may not be your imagination. several years ago. Perkins and colleagues so they devoted two years to getting it on Bowing to pressure from regulators, interviewed formulators, end users, envithe Safer Chemical Ingredients List mainthe makers of household and industrial ronmental groups, and consultants to untained by EPA’s Design for the Environcleaning products have been eliminating derstand the trends in the industry. They ment (DfE) program. It also won a place on solvents that work well but don’t meet govalso attended conferences where they enthe CleanGredients list maintained by the ernment standards for toxicity or volatile countered skeptics who dismissed the idea nonprofit GreenBlue. organic compound (VOC) content. of safer solvents with the phrase “green Meanwhile, the company scaled up buSome companies have removed ethylene does not clean.” tyl 3-hydroxybutyrate output, turning its glycol monobutyl ether, which is considUndeterred, they decided to approach Kingsport, Tenn., headquarters complex ered a hazardous substance in California. the problem methodically. The first step, into what de Wit says is the world’s only Products such as dipropylene glycol monoaccording to Jos de Wit, an large-scale producer. And it OH O methyl ether are being replaced because analytical chemist at Eastbranded the solvent with the the Environmental Protection Agency has man who worked on the projtrade name Omnia. O deemed them to be VOCs. These may be ect, was to assemble a dataOmnia is now fully comButyl 3-hydroxybutyrate sound moves for health and the environbase of some 3,000 molecules mercial, Perkins says. To ment. But according to Carol Perkins, with potential as cleaning solvents. date, Eastman has one customer, in Euhead of Eastman Chemical’s industrial and Eastman scientists put the solvents rope, and several other firms are evaluating household care business, “It has left a big through in silico screens that sifted for the solvent, she notes. Eastman is initially void in terms of performance.” molecules with the right balance of hytargeting the industrial and institutional Eastman, a major manufacturer of soldrophilic and lipophilic properties. The cleaning market because of its need for vents, decided to do something about it. researchers whittled the database down to new solvents and because customers value The result, being rolled out now, is butyl 370 candidates and then began screening third-party certifications such as DfE. 3-hydroxybutyrate, a chemical that Eastfor safety. At 70 compounds, they emVince, the consultant, notes that other man says is new to the cleaning industry barked on in vitro and other toxicological firms are also coming up with new cleaning and, in fact, new to commerce altogether. testing and pared further. chemicals. For example, a partnership beThere’s no doubt that cleaning product The first molecule to emerge from the tween Stepan and Elevance Renewable Scimakers need new solvents, according to screen, an ester alcohol, was a bust, de Wit ences recently launched a naturally derived Martin Vince, a formulation chemist who says. It was a decent cleaner, but after testsurfactant, N,N-dimethyl 9-decenamide, as runs an Ontario-based consulting firm ing, the researchers realized it didn’t meet a solvent replacement. And Dow Chemical called LizMar. Vince figures that 30% of his California’s VOC standards. is promoting dipropylene glycol phenyl business today is with companies looking Around the same time, the screening ether and other VOC-compliant solvents. to replace solvents and other ingredients process also yielded butyl 3-hydroxybutyPerkins prefers not to put her team’s for environmental reasons. rate. Another ester alcohol, it passed the effort in terms of Eastman’s competition The need is greatest in the industrial VOC test. But did it clean? or the solvents the firm wants to replace. market, Vince says, because cleaning prodWhen the Eastman team embarked on Rather, Eastman has a loftier ambition for ucts must be able to remove caked-on dirt, the search for a new solvent, it learned Omnia: “We want to change the chemistry grease, and grime without smearing. the industry had no standard way to asof cleaning,” she says.—MICHAEL MCCOY
CLEANING CONUNDRUM
CEN.ACS.ORG
24
JUNE 9, 2014
