Advertisement

If you have an ACS member number, please enter it here so we can link this account to your membership. (optional)

ACS values your privacy. By submitting your information, you are gaining access to C&EN and subscribing to our weekly newsletter. We use the information you provide to make your reading experience better, and we will never sell your data to third party members.

ENJOY UNLIMITED ACCES TO C&EN

Business

Going Green

Pushed by Wal-Mart, legislators, and the public, the cleaning products industry embraces sustainability

by Michael McCoy
January 29, 2007 | A version of this story appeared in Volume 85, Issue 5

ONE WOULD NOT EXPECT a Procter & Gamble laundry detergent to share advertising space in the New York Times Magazine with expensive watches and designer clothing. But this is not just any detergent; it's an environmentally friendly one.

Over the past year, the environmental impact of consumer products has gone from being a fringe issue raised mainly by activist groups to a mainstream concern confronted by P&G, Wal-Mart Stores, General Electric, and other marquee names of corporate America. The leaders of these companies no doubt have a genuine desire to improve the environmental profile of their products. But they also know green sells, and firms perceived as being kind to the environment look as good to the well-heeled readers of upscale magazines as they do to the investment community.

Wash day
[+]Enlarge
Credit: Henkel
Laundry detergent makers say they test products for effectiveness as well as environmental impact.
Credit: Henkel
Laundry detergent makers say they test products for effectiveness as well as environmental impact.

Because laundry detergents are bought in large volumes, mixed with water, and sent down the drain, they have been front and center in the environmental discussion. Raw materials are being scrutinized and in some cases phased out. Suppliers are being asked to come up with new, more environmentally sound ingredients to help consumer goods companies head off scrutiny or present a greener product lineup.

The P&G ad, for Tide Coldwater, is aimed at an environmentally conscious audience. It points out that if everyone in New York City washed laundry in cold water for just one day, the energy saved would be enough to light the Empire State Building for an entire month. It then suggests that Tide Coldwater, introduced in early 2005, can help accomplish this goal.

P&G is the world's largest laundry detergent company, and when it speaks, suppliers of surfactants and other raw materials listen. Thus, for Tide Coldwater, P&G's surfactant suppliers designed a hydrophobic surfactant system that solubilizes oily soils in cold water. And its enzymes suppliers developed proteases and carbohydrases that are effective on insoluble dirt residues in cold water.

In turn, P&G and other consumer product companies must heed Wal-Mart, which has the second highest annual sales of any publicly traded company in the world. And Wal-Mart spoke loudly last fall when it announced two environmental initiatives that could profoundly affect cleaning products.

In September, at the Clinton Global Initiative in New York City, Wal-Mart launched a plan to measure its 60,000 worldwide suppliers on their ability to reduce packaging. It calculates that the plan will annually save 323,000 tons of coal and 67 million gal of diesel fuel from being burned. And it will keep some 677,000 tons of carbon dioxide out of the atmosphere.

[+]Enlarge
Credit: P&G
Credit: P&G

Then in October, the company started a program to encourage the use of "preferred" ingredients in detergents and other chemical-intensive products. Wal-Mart said it would work with suppliers to substitute 20 "chemicals of concern" over the following two years. It announced the first three chemicals in October, one of which was nonylphenol ethoxylates, or NPEs, a surfactant class found in many cleaning products.

Wal-Mart's initiatives came at a time when cleaning product makers and their raw material suppliers were already reeling from a string of initiatives that are changing the way they develop their products. These include the European Union's detergents directive and its REACH chemical regulation plan, the Environmental Protection Agency's Design for the Environment program, and a state-level ban of phosphates in automatic dishwashing detergents.

But Wal-Mart's size and direct influence on the industry give its two initiatives a particular impact. And because it is a private company, Wal-Mart can immediately present its changes to suppliers and consumers without the deliberative process that government agencies must follow.

"The retailers are one step closer to the consumer and can, as Wal-Mart has proven this year, have a dramatic influence on consumer perception," says Kevin Beairsto, business manager for fabric and home care at National Starch & Chemical's Alco Chemical division. "Removal of fillers and other chemicals due to packaging and environmental concerns poses formulation challenges to detergent manufacturers and ultimately to us as ingredient suppliers."

Corporate rather than government scrutiny of chemical ingredients is a potentially game-changing development for cleaning product companies. "Corporations, such as the retailers, like to move fast," points out Ernie Rosenberg, president of the Soap & Detergent Association, the main trade group for the U.S. cleaning products industry. "A deliberative process with stakeholder participation doesn't give you a fast process."

LIKE THEM or not, lists such as Wal-Mart's 20 chemicals of concern, in Rosenberg's view, could prove to be more important arbiters of the chemical industry's product lineup than any traditional regulation. "Once it's on a list, public pressure and retailer pressure is what hits the chemical," he says. "It may get regulated down the road, but for consumer products, that may be irrelevant."

NPEs provide an instructive example of how listing, even in the absence of government action, catalyzes change. The surfactants also demonstrate how an unwanted development for one company or product is a business opportunity for other companies and products.

NPEs and other alkylphenol ethoxylates (APEs) have long been under scrutiny. According to a Sierra Club report published in November 2005, they are unlike any other cleaning agent because they break down into more toxic, less biodegradable metabolites that display estrogenic properties, such as nonylphenol itself. The APE Research Council, an industry group, contends they are safe.

Thomas Stephens, global business manager for cleaning and care at Dutch chemical maker Akzo Nobel, notes that Europe effectively banned NPEs in the 1990s for all down-the-drain applications. No legal prohibitions exist in the U.S., but EPA's Design for the Environment program recognizes companies that voluntarily phase out the manufacture and use of NPEs.

Perceptive
[+]Enlarge
Credit: Degussa
Eunjoo Kim, a chemist in Degussa's Hopewell, Va., laboratories, evaluates softness and fragrance retention benefits of ingredients offered by the company.
Credit: Degussa
Eunjoo Kim, a chemist in Degussa's Hopewell, Va., laboratories, evaluates softness and fragrance retention benefits of ingredients offered by the company.

Not surprisingly, they have been on the decline. A recent Consumer Reports study concluded that no major U.S. brand of laundry detergent contains NPEs. Sharon J. Mitchell, vice president of R&D for P&G's global fabric care business, says her company has never formulated fabric and home care products with NPEs, "as we realized from the beginning that these chemicals could not be supported for safety at the volumes that would be required." In institutional cleaning products, where NPEs have persisted, key player JohnsonDiversey announced last summer that it would eliminate them by the end of 2006.

Yet, according to the Sierra Club report, more than 260 million lb of NPEs were consumed in the U.S. alone in 2004, and observers say they are heavily used in Asia for textile processing and other applications. Companies such as Dow Chemical, Huntsman Corp., and Rhodia say they are safe and continue to manufacture them.

"Wal-Mart's going to do what Wal-Mart's going to do," says David Parkin, Huntsman's vice president for intermediates. "We still believe NPEs are an effective cleaning agent and will provide them." At the same time, Parkin acknowledges that some companies are shunning them, and he says Huntsman is prepared to assist them with replacements such as methyl ester ethoxylates and blends of alcohol ethoxylates and ethanolamines.

In fact, while it continues to produce a chemical that concerns the likes of Wal-Mart and P&G, Huntsman last year launched a business unit charged with enhancing its practice of green chemistry that reduces the use or generation of hazardous products.

For cleaning products, Parkin says Huntsman is investigating the manufacture of propylene glycol from natural glycerin. It is using a new catalyst to combine palm-kernel-derived methyl esters and ethylene oxide to produce methyl ester ethoxylates with strong performance in cleaning applications.

"We are about providing flexibility to our customers," he says. "Although we have a good capability to develop green chemistries, there is a large market of NPE users that continue to see them as effective cleansers."

Rhodia, another NPE producer, has been researching NPE alternatives for the past five years, according to Pascal Metivier, vice president for innovation and technology at the firm's Novacare unit. "We systematically try to pursue replacements," he says. "But ultimately, the customer decides."

In the agrochemical market, where surfactants are used as emulsifiers and wetting agents, Rhodia has completely replaced NPEs with blends of other surfactants, Metivier says. Sales to detergents and other industries continue to fall, he notes, but some hang on to them because they are inexpensive and effective. "Replacing NPEs is easy. Replacing NPEs at the same cost is not," he says.

At Akzo Nobel, which also produces NPEs, Stephens says the company is developing replacements by drawing on its experience in Europe. "We have gone through the trial and error of what works and doesn't work," he says.

NPEs contain nonylphenol, a hydrophobe that is attracted to oily materials, and ethylene oxide, a water-loving appendage that keeps the molecule in solution. Although the cleaning products industry's initial direction in NPE replacement was toward linear alcohol hydrophobes, Stephens says Akzo has found branched hydrophobes to be effective without the excessive foaming often associated with linear alcohols when they are ethoxylated. A new narrow-range ethoxylation technology also lowers foaming in both linear and branched products, he adds.

While NPEs are on the wane in the U.S. mostly due to corporate initiatives, phosphate builders for automatic dishwashing (ADW) detergents are under pressure from good old-fashioned government action.

[+]Enlarge
Credit: Henkel
Credit: Henkel

Phosphates provide several functions in detergents, including hard-water neutralization, redeposition prevention, and buffering. But concerns about phosphorus-induced eutrophication in lakes and rivers led to a series of state-level bans in the 1990s that took phosphates out of most U.S. laundry detergents. ADW products were spared, though, and today many of them contain 4-8% phosphorus.

The State of Washington revoked that reprieve last June with the passage of an ADW phosphate ban intended to protect the Spokane River. It will go into effect on July 1, 2008, in three counties said to have phosphate problems and in 2010 in the rest of the state.

Whereas laundry detergent phosphates were replaced with citrates, zeolites, and other builders without major cost and performance compromises, detergent makers contend that phosphates are key to dishwasher detergent performance and that their absence will be noticed by consumers. Thomas Müller-Kirschbaum, senior vice president for R&D, technology, and supply chain with Henkel's laundry and home care business, says Henkel launched a phosphate-free ADW product in Germany about 10 years ago. "We lost market leadership and had to go back to phosphates to take the lead again," he says.

U.S. ADW detergent makers surely don't relish the prospect of coming up with a separate formula for Washington state or, worse, watching the ban spread throughout the West and across the country. Some specialty chemical companies, though, see the ban as a business opportunity whose arrival was inevitable.

"We have been telling people for some time that you can take phosphates out of ADW products and get comparable performance," says Nilesh Shah, global research director for process chemicals and biocides at Rohm and Haas.

According to Shah, effective phosphate replacement technology had been languishing on Rohm and Haas's laboratory shelves until the Washington state ban emerged. At its heart is Acusol 425N, a water-soluble acrylic polymer that, the company says, can remove food soil and keep it dispersed while controlling the deposition of carbonate scale on glassware and utensils.

At Alco, another specialty polymer supplier, Beairsto sees both pros and cons in an ADW phosphate ban. On the one hand, a number of Alco's polymers are used in current ADW formulas to prevent the filming caused by calcium phosphate scale. But Beairsto isn't surprised by the ban and, like Shah, says Alco has had zero-phosphate ADW projects under way for several years now. "We have developed several technologies that can help mitigate the negative effects of the removal of phosphates," he says.

At the specialty chemical company Croda, which acquired the surfactants maker Uniqema last September, Sales Development Manager Rob Pifer points to the Synperonic NCA series of alkoxylated copolymers, detergent boosters that allow formulators to reduce or remove the need for builders. Initially developed for the European market, the series complies with the new European Detergents Directive mandating surfactant biodegradability, he says.

Like NPEs, phosphates are effective cleaning agents unlikely to be replaced by a single ingredient. But the right combination can address ecological and toxicological concerns and still achieve the necessary functional properties, according to Tony Latella, detergents sales director in North America for BASF's performance chemicals business. He says a blend containing BASF's Trilon biodegradable chelating agent, Plurafac surfactants, and Sokalan polymers can "actually add utility and help boost product performance compared to many phosphates."

Advertisement

Chemical companies are also positioning their ingredients to replace formaldehyde releasers, solvents, and other cleaning product components that may not be regulated but are seen as undesirable just the same. Shah says Rohm and Haas isothiazolone biocides are gaining as replacements for formaldehyde-releasing biocides such as dimethyl dimethylol hydantoin and 1-(3-chloroallyl)-3,5,7-triaza-1-azoniaadamantane chloride, also called quaternium 15.

Among solvents, one target is ethylene glycol butyl ether, a solvent commonly found in spray cleaners. Although EPA took EGBE off its list of Clean Air Act-regulated pollutants in 2004, it is still considered a volatile organic compound by the influential California Air Resources Board.

New Formula
[+]Enlarge
Credit: Rohm and Haas
The reemergence of highly concentrated detergents poses formulation challenges for ingredients suppliers.
Credit: Rohm and Haas
The reemergence of highly concentrated detergents poses formulation challenges for ingredients suppliers.

According to Akzo Nobel's Stephens, 1% of the company's Berol 226, a blend containing nonionic and cationic surfactants can replace the EGBE and NPE that are in many spray cleaners. One big U.S. brand made the switch in the 1990s, he says, reducing VOC emissions and increasing the product's ability to emulsify and remove gritty particulate matter. "It's one of those rare times we have shown we can do the job better for less money," he says.

ALTHOUGH BANS and regulations are real events with real repercussions, cleaning industry players insist they aren't merely being reactive. From cold-water formulas to new concentrated detergents to ingredients that come from renewable resources, fabric care companies and their raw material suppliers are trying to make sustainable products that satisfy the public's new environmental sensibility.

"We work with suppliers to ensure that all new raw materials meet stringent P&G safety criteria," says Mitchell, the P&G vice president. "P&G safety scientists are involved in this process right from the beginning, sometimes even before the actual materials are synthesized."

Above and beyond basic safety, Mitchell says, P&G often uses a "life-cycle assessment" tool to determine the water, packaging, and energy consumption associated with its products. New products that have benefited from this tool include Tide Coldwater, a single-rinse Downy fabric softener, and compact laundry detergents soon to be available in North America. The company advises Wal-Mart on the retailer's sustainability initiative, Mitchell adds, and is in its Chemical-Intensive Products Network.

P&G even backs particular ingredients to help it reach environmental goals. For years, Mitchell says, the company has worked with leading enzymes suppliers to develop enzymes that enable it to use less surfactants and other chemicals. "We are also increasing the level of naturally based surfactants in our products," she says, "using alcohols from natural oils to reduce the level of petrochemically based surfactants we use."

P&G's competitors are flying the sustainability flag as well. Henkel, a European laundry detergent leader, was one of the first companies to recognize a poorly biodegrading ingredient some 50 years ago when it removed branched alkylbenzene surfactants from its detergent formulas, according to Müller-Kirschbaum. In the past decade, he adds, Henkel has removed suspect dyestuffs from its detergents, replacing them with food-grade and other more benign dyes.

And although all detergent companies have their roots in natural soaps, Müller-Kirschbaum says Henkel has stayed more true to them than most. Today, about 35% of the surfactants it uses in laundry detergents and household products come from renewable resources, he explains. "We feel prepared to say to Wal-Mart that we are a benchmark in our industry, especially in the use of renewables."

Recent Henkel environmental initiatives in Europe include the launch last year of a new detergent, Persil Color, developed to work well at low temperatures. According to Müller-Kirschbaum, its effectiveness stems from a specially tailored stain-removal polymer, improved enzymes, and a reworked surfactant system.

Similarly, Henkel's latest ADW product, Somat 7, is formulated to clean as well at 40 oC as previous products did at 55 oC, for a 20% energy savings.

Ingredient suppliers say environment-oriented requests by customers such as P&G and Henkel have become a new part of the customer-supplier relationship. According to Rhodia's Metivier, customers have always been interested in reducing costs and gaining attributes that allow them to make new marketing claims. "What is new in the past two years is the very aggressive stance of customers on green issues," he says.

In particular, ingredient suppliers are helping customers develop detergents that perform in cold water as well as traditional products. At the 6th World Conference on Detergents in Montreux, Switzerland, in October, Per Falholt, executive vice president for R&D at the enzymes producer Novozymes, made the case for cold-water washing using detergent enzymes.

He described a life-cycle assessment of adding extra protease, lipase, and amylase enzymes to a laundry detergent while dropping the wash temperature from 40 oC to 30 oC. Wash performance improved by almost every measure, he reported, and the energy savings of making the change in Europe would be equivalent to the output of two major power plants. Falholt said Novozymes is now working on enzyme packages for washing at 20 oC.

The energy-saving companions to low-temperature detergents are highly concentrated products that answer Wal-Mart's call for less packaging. Unilever was the first big detergent maker to hit the market, with its All Small & Mighty liquid, launched in February 2006. According to Unilever, a 32-oz bottle of the new All can wash as many loads of laundry as 100 oz of traditional detergent. Unilever says its annual manufacturing and shipping savings will amount to 500 million gal of water, 26 million gal of diesel, and 150 million lb of plastic.

Concentrated detergents were rolled out in the U.S. about 15 years ago with limited success, and most of them disappeared. Patrick Cescau, Unilever's chief executive officer, told attendees at the Montreux detergents meeting that the company had been concerned the new attempt at concentrates might lead U.S. consumers to think they are getting less for their money.

To combat this impression, Unilever formed a partnership with Wal-Mart under which the retailer agreed to promote the new All to increase consumer confidence and get sales moving. "You can now find All Small & Mighty in supermarkets across the U.S.," Cescau said.

In Europe, where powdered detergents prevail, dosages have been on the decline as well, to about half the volume prevalent in the early 1990s, notes Henkel's Müller-Kirschbaum. He adds that Henkel's Dial subsidiary in the U.S. has developed a concentrated version of its Purex liquid detergent that will appear on store shelves soon.

Dave Del Guercio, director of Degussa's household care business in North America, points out that many ingredient suppliers developed concentrated detergent formulas during the market's earlier flirtation with the format. In Degussa's case, the focus is on hard-surface cleaners and fabric softeners, where the company is a leading supplier of ester-type quaternary ammonium cationic surfactants.

THE CHALLENGE of formulating concentrated cleaners is pretty straightforward, Croda's Pifer says: "How do you produce a heavy-duty product with less water in the formulation?" One of Croda's responses is Monateric 1188M, a low-toxicity additive that helps keep high-concentration formulas stable.

One result of higher surfactant concentration in liquid detergents is increased viscosity, BASF's Latella notes. Depending on the surfactant phase, formulators may be faced with unfavorable rheology, or flow properties, especially when the liquid is being poured out of the bottle. Latella says BASF's nongelling Lutensol XL and XP nonionic surfactants can help address dissolution and stability problems associated with concentrated liquids.

Rohm and Haas's Shah doesn't see formulation problems in household concentrates as much as in industrial cleaners that contain phosphates, carbonates, and other ingredients with limited solubility. "Stability becomes an issue and rheology modification can become necessary," he says. "You need to modify the liquid phase to make these cleaners work."

Do consumers know or care about the changes the cleaning products industry is making to create more environmentally improved products? Will green detergents sell?

On the one hand, detergents from the self-proclaimed "nontoxic" household products maker Seventh Generation are starting to show up in mainstream supermarkets. Farther down the aisle, though, Unilever's All Small & Mighty bottles don't mention energy and product savings. The emphasis is on convenience, and interested consumers must go to the detergent's website to learn about the environmental benefits.

Alco's Beairsto, for one, thinks consumer sentiment—or at least legislative sentiment—is moving toward more environmentally friendly products. "The real test of their conviction will come when consumers realize that the new products may either cost more or work less effectively than the products they currently use," he says. "Our challenge is to provide environmentally friendly technologies that deliver the benefits consumers have come to expect at a cost they are willing to pay."

[Top of Page]

Article:

This article has been sent to the following recipient:

0 /1 FREE ARTICLES LEFT THIS MONTH Remaining
Chemistry matters. Join us to get the news you need.