Floor Finish

New products tout advanced chemistry
Of the many reasons building service contractors purchase a particular brand of floor finish, the size and arrangement of polymer molecules probably isn’t at the top of the list. But the specific chemistry of floor finish does have a direct effect on durability, appearance and safety — the qualities that matter most.

Most recent floor-finish innovation has come from its packaging and proportioning, rather than from its formulation. And those pre-measured packets, dilution-control systems and strong concentrates certainly have made floor care safer, more accurate and efficient.

But there are some products on the market that use new developments in polymer chemistry to achieve the desired results. Two such products are Betco Corp.’s BetcoBest™ floor finish with the MMT/50™ polymer, which utilizes a larger molecule; and Multi-Clean’s Ultra Brite II™, which uses ultraviolet light to create a new polymer right on the floor. Other manufacturers also may have their own new technologies waiting in the pipelines.

When choosing between these and other new products, BSCs can look to their chemistries — by reviewing labels and material safety data sheets — to better understand where the claims of “a high-gloss shine” or “50 percent more durable” come from.

Some larger BSCs have their own test labs so they can evaluate chemicals before they add new ones to their closets — or, in the case of Downers Grove, Ill.-based ServiceMaster, so they can develop their own chemicals if needed.

Mike Kerner, ServiceMaster’s director of consumer services, implementation and training, says his department tests chemicals, equipment and processes in order to put together the best possible package for the company’s 72,000 employees worldwide.

The lab analyzes chemicals primarily for the outcome but also for the chemistry, especially for safety or regulatory concerns. For instance, volatile organic compounds in floor finish, such as solvents and ethers, can be subject to government regulations.

In addition to safety, Kerner and other BSCs want the chemicals in a floor finish to add up to real-world results.

“If we were developing a floor finish for our retail business, we’d focus on durability,” says Mike Bondi, president of Triad Services, Denver, who recently helped test the new Betco finish. “It needs to stand up to daily propane burnishing. Labor is our highest cost, and the farther we can spread out recoats, the better.”

Bondi’s customers, on the other hand, desire a high gloss level.

“They want to be able to see the reflection of each light bulb in the floor,” he remarks.

Understanding floor-finish chemistry can help BSCs know what to look for on the label or material safety data sheets when trying to find the best product to fulfill these requirements.

Floor finish 101
Floor finish actually is a blend of several different chemicals added to a water base.

“Choosing the correct ... ingredients gives the right balance of viscosity, flow, leveling, gloss, durability, clarity and stability to the floor finish,” says Paul Lewis, a group leader for Johnson Wax Professional, Sturtevant, Wis.

Here’s a brief run-down of what’s actually in a typical, water-based acrylic floor finish:

• The acrylate polymer backbone makes up the lion’s share of the solid matter in the floor finish. The polymer, which is a type of plastic, gives the floor finish its strength, durability and shine. Polymers are made only by a handful of laboratories. Floor-finish manufacturers buy polymers from these companies, then use them in their floor finishes.
  

The polymer is combined with water to form a polymer emulsion. Then, many components are added to the backbone to modify its nature.

• A wax emulsion is added to change the softness or glossiness of the finish. Synthetic polyethylene or polypropylene waxes have replaced natural waxes in many finishes because of their improved consistency in color, performance and availability, writes Roger McFadden, technical director and senior chemist at Paulsen & Roles Laboratories in Portland, Ore, in a Web-based publication at www.coastwidelabs.com.
  

• Coalescing agents, usually some sort of glycol ether, or another solvent, help to soften up the polymer particles, Kerner explains. As the water in the floor finish evaporates, it leaves the solid behind. The polymer needs to coalesce — fuse together — to form a film on the floor surface. Otherwise, the finish would remain in droplets.
  

Gylcol ethers and solvents are considered volatile organic compounds, and in some concentrations are regulated by the U.S. government, he adds.

• A plasticizing agent also is added to ensure the finish remains malleable and doesn’t crack after it sets.
  
• Alkali-soluble resins are added to improve the ability of a finish to level.
  

“Floor finish comes off the mop in droplets,” Kerner says. “It should level when set.”

The resins also make stripping the floor easier when it’s time to remove the finish.

• A wetting agent, or a series of surfactants, helps the liquid spread.
  

“Typically, floor finish is applied to vinyl,” says Kerner. “Vinyl tends to be hard to wet. The liquid beads instead.”

Unfortunately, the surfactants can produce bubbles in the film, causing a “cratering” affect. To combat this, manufacturers add a foam suppressant.

• Preservatives help keep the finish stable. Antimicrobial agents help prevent the growth of microorganisms, and sometimes, an antifreeze agent is added to provide freeze-thaw stability, McFadden writes.
  
• Other additives include pigments, fragrances and other compounds that improve the appearance, stability or slip resistance of the floor finish. There literally are hundreds of thousands of possible additives, and each floor finish contains a different mixture.
  

From the mop to the stripper
To a janitor, applying floor finish seems to be a mop-cure-buff process. The customer sees the furniture moved, waits for the floor to dry, then hopefully, gets a nice gloss. But a chemist sees the floor-finish process in a different light, at the molecular level.

“Because plastic isn’t water-soluble, it comes off the mop in particles, called micelles,” Kerner explains. “The particles are surrounded by the surfactant.”

After the floor finish is applied with a mop, the water evaporates and the micelles coalesce into one cohesive film. Floor finish coats can dry in anywhere from a few minutes to a few hours, but often, especially in humid areas, it may take a few days for the finish to fully cure.

“If you try to apply traffic before the finish has cured, the micelles move around,” Kerner says. The result is an uneven or cratered finish.

Once cured, the floor can tolerate detergents, spills and machine buffing. But only to a point — after awhile, the floor usually needs to be refinished.

“Even if we put on several coats of finish, routine scrubbing and machine maintenance gradually wears away the finish,” says Kerner.

Foot and other traffic also degrades the finish. High heels and golf spikes can chip or gouge finish. Tracked-in sand and other abrasives gradually grind the finish away.

Ice melt is a big problem for floor finish in many areas of the United States.

“2001 was a tough winter for us,” says Bondi. “The problem is they’re using a mixture of liquid magnesium chloride and sand as ice melt.”

The magnesium chloride, when tracked in, pits the floor finish and also is very slippery, he explains.

Also, because of alkali-soluble resins in finish, using an alkali detergent can strip it away.

“Even a mild alkali will begin wearing down the finish,” says Kerner. “If you use a neutral detergent, you won’t get as much wear.”

Even if the finish doesn’t wear away, several problems can mar its appearance. Oily soils need to be cleaned right away, or they can absorb into the finish. And dirt left on the floor when recoating can give the finish a yellow appearance, as can too much exposure to the sun’s ultraviolet rays.

Bigger is better?
A goal, then, when creating any new floor finish, is to ensure it is more durable than previous chemicals. But unfortunately, much of the innovation, until recently, has been cosmetic: a new tint here, some more shine here.

At the chemical level, manufacturers have been slowly increasing the solids-to-water ratios of the finish to try to make it stronger.

“Twenty years ago, the highest solids ratio was about 16 to 18 percent,” Kerner says. “Now, I’ve seen 25 or 26 percent or more.”

The problem with that, however, is that too much solid makes the floor finish more viscous, and thus harder to apply. Workers notice a “mop drag,” sometimes to the point of back pain.

But Toledo-based Betco Corp. has developed a new technology that combines larger polymer particles, a low viscosity and a higher solids content to address this problem. This new technology, MMT/50™ (Macromolecular Polymer Technology), utilizes polymer particles that are much larger than those in typical floor finishes.

“It’s generally been the attitude that small particles are better, but we’ve ridden that out,” senior research chemist Steve Gwin explains. “Larger polymer particles have a decreased surface area for a better distribution of the particle.”

The larger molecule can improve the outcome of the floor finish, Kerner confirms. “A larger molecule generally is more stable, has a higher melting point and a lower solubility,” he says.

Betco also claims its new finish, BetcoBest™, which utilizes the MMT/50 polymer, dries 50 percent faster, requires 50 percent fewer coats and has a 50 percent thicker film than competitive products.

The MMT/50 technology is more than two years in the making, after a lot of trial and error, Gwin says. It would take a similar effort for another manufacturer to approximate Betco’s finish.

“There were a million different additives, plasticizers and so forth,” he says.

One of Betco’s goals was to create this high-solids floor finish with a low level of mop drag. How the company arrived at that goal is a trade secret, but Gwin says engineers tested the finish extensively in-house.

Viscosity is measured in centipoise (cPs), explains Gwin.

“Anything over 12 cPs, you begin to feel it in your back,” he says. “Some of the finishes we tested were over 30. We keep ours at six to nine.”

Once Betco engineers, in conjunction with chemists at the polymer lab with whom Betco contracted, were happy with the polymer, the company invited several BSCs from across the country to field test BetcoBest.

“We [work at] chains of grocery stores, and we’ve been using other products” by Betco and other manufacturers, Triad’s Bondi says. “But we felt we weren’t getting the results we wanted.”

Betco offered Triad the opportunity to field test its new floor finish, and Bondi agreed.

“I gave it to a supervisor whose opinion I respect,” Bondi recalls. “He came back and said, ‘We stripped the front aisle and put two coats down. It outlasted the six or eight coats of the other product.’”

The crews have noticed a slight mop drag, but nothing too severe, Bondi notes.

BetcoBest hit the general marketplace April 23, and Gwin says the interest in the product has been encouraging. Triad, in fact, has begun to change all its grocery stores over to the new product.

UV advances
Another innovation in floor-finish chemistry involves using the very ultraviolet (UV) light that can yellow some finishes. Shoreview, Minn.-based Multi-Clean developed a process that cures floor finish with artificial UV rays, and brought a product line to the market in November 1999. But BSCs can’t just take a sun lamp to their favorite floor polymers; Multi-Clean’s process creates the polymer on the floor itself.

“Normal floor finish is a fully reacted polymer, dispersed in water that’s cured by evaporation,” says senior chemist Mike Tarvin.

Multi-Clean’s Ultra Brite II™, on the other hand, isn’t shipped as a polymer; it’s shipped as the raw materials.

The user applies the floor finish, then passes over it with a special, walk-behind 22-inch curing unit. The UV-22 unit sends ultraviolet rays down to the floor finish, which causes a polymer to form from the raw materials and cure virtually instantly.

The system only requires one coat, and is more durable and longer-lasting than traditional finishes, claims Tarvin.

“The big advantage is that it eliminates a lot of labor,” he explains. “The system doesn’t require any high-speed buffing.”

Some sources in the industry, however, are speculating that the finish may be a little too durable, and may damage the floor surface if removed.

But UV product manager David Holly says the finish is intended to be nearly permanent; if it’s damaged, users can repair the spot. On the other hand, if one wanted to remove the film, it would need to be done in a process similar to sanding wood floors.

Right now, Multi-Clean is the only manufacturer of the patent-pending system, but customer interest has been high, Tarvin says.

Polymer chemistry isn’t a new field, but innovations such as large molecules and UV curing are in their infancy. Both Tarvin and Gwin say their companies are working to build more products based on their new technologies, and other manufacturers may be on the verge of breakthroughs of their own. BSCs should expect to see more options for their floors in years to come.