Today’s top coats promise to do everything under the sun, from preventing nail from yellowing, chippings, and peeling, to strengthening and helping them grow. Conventional top coats are designed to protect polish and add high-gloss shine. However, over the years top coat makers have reformulated this basic product and added more active ingredients so top coats do more than protect and shine. We’ve talked to marketers, chemist, and technicians for a clearer idea of what a top coat and cannot do.

A top coats’ function depends on its formulation. A top coat is simply clear nail enamel that contains a higher proportion of solvents so it dries faster. If atop coat claims to do more than offer a shiny, protective surface, it must contain specific additives to do so.

In contrast, a base coat’s function is to provide a bond between the natural nail and the polish to help polish adhere. A base coat’s formulation uses fewer dehydrating ingredients than a top coat, so it doesn’t dry as quickly.

The chemical properties of base and top coats are similar to polishes, colored or clear, contain nitrocellulose, resins, and plasticizers, ingredients that provide adhesion, strength, and flexibility. They also contain solvents and diluents, which keep the polish liquid before it’s applied and control drying time once it’s on the nail. Polish dries faster than a base coat and is more durable than a top coat.

Because of their different formulations and functions, top coats and base coats generally are not interchangeable. “They can’t be interchangeable,” says Tom Raffy, chemist and owner of Gar Laboratories (Riverside, Calif.), “because of their resin content. A true base coat won’t stay hard; it will be too porous. It won’t have any abrasion resistance.”

Doug Schoon, executive director of Chemical Awareness Training Service (Newport Beach, Calif.), concurs. “There are different types of polymers in polishes,” says Schoon. “Some give strong hard surface, and others offer good adhesion. Base coats have cranked-up adhesive properties, while top coats have more strength-enhancing polymers. The two are not interchangeable.”

According to Judy Michaels, a nail technician at Millionhairs (Malibu, Calif.), a base coat is supposed to dry, but still be tacky to the touch so polish adheres. “You don’t want a top coat to do that,” she explains. “A top coat is supposed to provide an ultimate shiny surface and to seal all the polish edges to prevent peeling.”

A spokesperson for SuperNail (Los Angeles, Calif.), says that some top coats can be used as base coats, but those that have an acrylic base should not, because the polish will not adhere as well.

TOP COAT FEATURES

Top coats are generally known for their high-gloss shine. Though polish itself looks shiny, it contains pigments and pigments-suspending agents that tend to reduce its gloss capabilities. Top coats don’t have these ingredients.

A top coat’s shine depends on the amount of nitrocellulose ad resin in it, says Martin Weisman, vice president and technical director at Sher-Mar Cosmetics (Canoga Park, Calif.). “The higher the levels of these, the higher the shine. A good high-gloss top coat has the same reflectance as a piece of glass,” he adds.

“Shine is due to the amount of dye in the polish,” says Allan Rubenstein, president of No-Miss Ltd. (Boca Raton, Fla.). “Color has a deadening effect on polish. When you eliminate the addition of color, like in a top coat, you can get a high shine from the acrylic nail.”

A top coat is designed to protect polish and help the nail withstand everyday stresses because its thicker coating is more resistant to impact. “Resin is a strong shock-absorbing polymer,” says Schoon, “so top coat will improve the durability of the nail.”

A top coat doesn’t actually strengthen the nail, says Rubenstein, but it works as lacquer and adheres to the last coat of polish and forms a bond. Terry Cutrone, president of Develop 10 says, “A top coat provides an extra layer of protection to seal the polish and keep nail color on. It brings the nail color out.”

Though a top coat can protect the nail, it can’t actually improve the health of the natural nail, nor can it increase the durability of artificial extensions.

“Chemically, a top coat doesn’t feed the nail,” says Peter Nelson, managing director of Pro Finish (Phoenix, Ariz.). “It can only provide a protective shield - an extra layer of protection.

Calvert Billings, owner of Calvert International (Laguna Beach, Calif.), agrees, “Since the nail itself is dead, all you are doing is putting some type of reinforcement over it to make it stronger.”

While a top coat can’t improve the health of the nail, says Sunny Lopez, a nail technician at DuBunne Salon (Torrance, Calif.), it can help natural nails by giving them extra thickness, extra strength, and hard finish.

Some top coats contain calcium, vitamins, and other so-called “healthy” ingredients, but because nails are dead protein, they cannot be strengthened by vitamin or mineral supplements. “None of these additives in a top coat can penetrate down to the nail plate,” says Weisman. “They just remain on the surface.”

Michaels believes that if the minerals and proteins make the top coat itself stronger, that’s fine. But they can’t penetrate doe to the natural nail and later the cell formation and structure, she says.

The same holds true for antifungal additives. They don’t have any effect, says Raffy, because the agents will never be released onto the nail. “They will be encapsulated in the top coat, so how can they react with the natural nail plate?” he asks.

Weisman explains that nail enamel itself is self-sterilizing and will not support any bacterial growth. “If you inject a fungus or bacterial into enamel,” he says, “the organism will die. Nail enamel doesn’t require a preservative because nothing will live in it.”

All fingernail experts and scientific articles and books, says Stone, agree that topical antifungals, whether over-the-counter or prescription, do not work on fungal infections of the nails or hair because they just can’t get to the fungus effectively enough to kill it.

Rubenstein offers a different viewpoint. “When you’re applying layer of polish, moisture can get between each layer,” he says. “The antifungal agent is more of a preventative measure to eliminate fungus growth.”

UV absorbers, on the other hand, are common top coat additives that do work. Just as sunscreen protects human skin, UV absorbers act as a sunscreen to protect synthetic material from the sun’s damaging rays. However, if a nail product contains a UV absorber, it doesn’t necessarily mean that the polish won’t eventually discolor, just as applying sunscreen doesn’t mean you won’t eventually burn.

In an article for NAILS on UV absorbers (July 1992), Eric Montgomery, chemist for OPI Products (N. Hollywood, Calif.), said the California midday sun can cause the average acrylic product to yellow noticeably within three days to two weeks, depending on the product’s formulation and quality, even if it does contain a UV inhibitor. But if the client applies a UV-inhibiting top coat every other day, the yellowing caused by UV light can be held off for a month or more. However, an acrylic product without a UV absorber and without a UV-inhibiting top coat would start yellowing immediately in direct sun.

Schoon say that UV absorbers work, but they are not the cure-all for yellowing. “There are no current products available that are completely immune to UV light, except for gloves,” he adds.

Cutrone, who recommends UV protection, says, “What causes polish to turn yellow is the nitrocellulose, because it’s made of finely ground cotton and wood fibers; both will eventually yellow when exposed to the sun.” UV absorbers attract UV rays away from the nitrocellulose.

FAST-DRYING TOP COATS

In general, top coats dry more quickly than base coats and nail polish because of their solvents. Most quick-dry top coats contain a higher proportion of solvents, which allow them to dry faster than polish and base coats.

However, they don’t speed the drying of underlying polish. “Many fast-drying top coats actually slow the drying process,” says Billings. “Because they dry so quickly, they don’t allow the first coat of polish to dry completely.”

Billings explains that the nail polish is a pigment and suspension agent solution, kept liquid by solvent that evaporate very quickly once exposed to air. The goal in drying nail polish, he say, is to release the solvents in the solution consistently and slowly. “If you put a quick-dry top coat over wet polish, it will dry only the part of the polish the top coat comes in contact with,” he explains.

However, says Michaels Reyzis, president of Art of Beauty (Cleveland, Ohio), in an article for NAILS on polish dryers (November 1991), “The correct proportion between solvent and solids in the quick-dry top coat will expedite drying without damaging nail polish, creating bubbles, or affecting color or quality. Besides these results, a good quick-dry top coat will give the technician a nice shiny finish to her work.”

Some technicians like to use fans or heat to help dry the top coat. Fans can speed drying, but they affect only uppermost polish layer, which means you’d have to use the fan after each coat for maximum effectiveness. Heat helps polish dry by speeding the release of solvents.

Another method for drying top coat is a UV light system. “The UV light is like a catalyst in that it creates a reaction with the photoreactive ingredients in the top coat, which causes it to harden,” says Nelson. “The UV light bonds the layers of polish together to create structural strength and to help it resist smudging, smears, and nicks.”

FORMALDEHYDE FACTS

Some people and top coats also may contain formaldehyde, a chemical that has gotten a bad rap in the nail industry. Many manufacturers have responded to the formaldehyde debate by developing formaldehyde-free nail polishes,

Formaldehyde, a commonly used preservative, is most widely preservative, is most widely associated with embalming, the chemical has many other uses, though, including its use as a nail polish resin. The FDA’s Cosmetics Division says there is no health risk from exposure to formaldehyde in the nail polish because it is molecularly bonded (forming a chain) with another chemical. Formaldehyde poses a risk, says the FDA, only when it is not bonded with other chemicals.

Though some manufacturers agree that the formaldehyde in polish is not a form that can be harmful, some companies have omitted formaldehyde from their formulas because they fear that technicians may not understand that, when properly used, the chemical poses no health risk.

“The formaldehyde level in polish is very low - about .001% maximum, so it is not harmful,” says Schoon. “Substitutes are not as good; they have stability problems. Also, shelf life [of formaldehyde-free products] is low, surfaces are not as hard glossy, and they are prone to more chipping.”

Rubenstein also says that formaldehyde resins are perfectly safe because of their low amounts in polish and the fact that they are very refined. One of the benefits of formaldehyde, he says, is a higher shine out of the color.

Formaldehyde-free polishes don’t adhere as well as conventional polishes that do contain formaldehyde resin. But they are good news for the small percentage of the population that is allergic to formaldehyde.

Many women are sensitive to formaldehyde, which can irritate the cuticle and discolor the nail, says SuperNail. Sensitive clients should be serviced with formaldehyde-free products.

LONG-LASTING PROTECTION

Both manufacturers and technicians agrees that applying a top coat regularly over natural nails or artificial extension will extend the wear of polish and reduce chipping and pealing.

“A top coat at least doubles the life of the polish,” says Lopez, “and it can protect papers you’re working with. If you don’t use a top coat, you can transfer color from polish to paper.” Without a good base coat or top coat, she says, the polish won’t last for more than 24 hours.

How long a polish job will last with a top coat depends on the client’s lifestyle, says Michaels. “If they’re busy and active, it’s going to wear sooner. If you’re polishing over acrylic, you don’t have the oil from the natural nail causing lifting. The natural nail is porous and will absorb moisture. As moisture evaporates, the nail will pull back.”

TOP COAT PREFERENCES

Since there are a number of top coats available with any combination of ingredients, a nail technician can select what she needs based on the services she performs.

“I like to use a top coat that dries quickly for artificial nails,” says Lopez, “because that’s usually what the client wants. But, unfortunately, the faster they dry, the less durable they are.” Lopez uses a top coat that dries hard for natural nail to give them strength and durability.

Michaels also uses a top coat that dries strong on natural nails and is flexible too. “You can use just about anything on artificial nails,” she says, “as long as it dries quickly and provides optimum strength and shine.”

HOME MAINTENANCE

Top coats are an ideal retail item for clients because home maintenance is essential for long-lasting durability and protection of the polish.

Says Lopez, “I urge client with natural nails to wear gloves at home. Because of the porousness of the natural nail, they need extra protection from water and chemicals.” Lopez recommends applying a top coat over natural nail every once to two days.

“Clients with artificial nails should apply top coat a week to rejuvenate their shine,” says Lopez. “If they’re wearing a light-colored polish, they should use a non-yellowing top coat at home.”

If clients follow these suggestions, she says. Both natural nails and artificial extensions should last about two weeks.

According to Carrie Brooks, a nail technician at It’s A Crazy World (Hermosa Beach, Calif.), a client should apply top coat over her natural nails every two to three days to seal and strengthen the nail. By doing this, her polish should last at least a week. For artificial nails, Brooks suggest applying one more coat between fills for clients who are hard on their nails.

For both natural and artificial nail wearers, Michaels recommends wearing gloves at home to limit direct exposure to water. “If you get a hairline crack in an artificial nail,” she says, “moisture can get in.”

Michaels tells clients to get a soft bar soft and run their fingernails across the soap to avoid staining their nails and to displays dirt before putting gloves on when gardening. Then, after they’re finished gardening, she says, they can use a nail brush to wash off the soap that’s already there. “I often remind my clients about a quote I once read,” muses Michaels, “that said our nails are jewels, not tools. I think that’s something worth mentioning,”

Top coats are the ideal tool to protect your clients’ jewel. In addition to protecting polish and offering a high-gloss shine, today’s top coats have been formulated to prevent nails from chipping, peeling, and yellowing, help them grow, to add strength. While some claims simply are not true, the majority of top coat can do exactly what they’re designed to do.

HOW SAFE IS TOLUENE?

First was methyl methacrylate in the 1970’s then formaldehyde in the 1980s. And now, ever since California’s Proposition 65 took effect in January 1987, toluene is attracting industry attention.

Toluene is an organic solvent that is used in nail polishes, top coats, and base coats, and base coats, and base coats. There are other organic solvent, alcohol, and acetone among them, used in the nail products.

Toluene, however, has garnered much attention because it is one of a number of chemicals in a California law (enacted after the passage of Proposition 65) that are suspected of causing birth defects and cancer. The state requires manufacturers to post consumer warning if the chemical exceeds a set amount.

Although toluene is on this list of hazardous chemicals, there is evidence that the amount of toluene found in nail polish does not pose a threat to users.

“California’s concern was to ensure that exposure to toluene would be below the amount California sets as a safe exposure,” says Dr. Gerald McEwen, vice president of science for the Cosmetics, Toiletry, and Fragrance Association (CTFA).

Proposition 65says that if the use of the product will result in an exposure greater than 1,000 times below the “no observable effect” level (the amount scientist says a person can be exposed to with no observable effect on the health) the product must have this warning label.

To determine whether nail polish required warning labels, the CTFA undertook a study to determine what a user’s exposure level to toluene actually is from polishing nails. The CTFA found that the exposure level toluene was 10,000 times below the no observable effect level, or 10 times less than the Proposition 65 maximum.

“We did a study with women applying products in an area the size of bathroom with practically no ventilation,” says McEwen. “We assumed that a person polished once a day. A person working as a manicurist could be exposed much more. But, assuming the person in the salon has even simple ventilation, there should still be no problem.”

LONG-TERM EFFECTS

Toluene does not build up in your body, so daily exposure to its no more dangerous than any single exposure. This means that healthy people can work with toluene without any effect as long as they are not overexposed any one time. However, pregnant women should try to limit their exposure during pregnancy can cause birth defects.

Although Proposition 65 covers nail technicians as “consumers” because they purchase the nail polish, the health of nail technician also falls under the authority of OSHA, which sets a permissible exposure level (PEL) to toluene at 100 parts per million (100 molecules of toluene to one million parts breathing air).

“OEL are intended to protect the health of a person who is exposed to a chemical every day over a working lifetime,” says HESIS Fact Sheet No. 10 from the Hazard Evaluation System and Information Service.

“Even if you took two or three bottles of polish and evaporated them into the salon air, you would still not reach 100 ppm,” says Doug Schoon, a chemist and director of Chemical Awareness Training Service (Newport Beach, Calif.).

Although from current research it’s fair to say exposure to toluene in the level it exist in nail products is safe, it’s important to limit your exposure as much as possible to any hazardous chemical. Always work in a well-ventilated area and cap all products tightly when they’re not in use to minimize evaporation.

“The most effective way to prevent overexposure is to use a safer chemical, if one is available,” state HESIS Fact Sheet No. 10. “However, the health and safety hazards of substitutes must also be carefully considered to ensure they are actually safer.”

Even with the growing industry controversy, toluene is the predominant solvent used in nail polish because, say chemist and manufacturers, it is the most effective. Manufacturer’s chemist and manufacturers, it is the most effective. Manufacturers’ chemist say that polish without toluene simply won’t stay on the nail.

Today’s concern over toluene can be compared with the “saccharin scare” of the 1970s. When the artificial sweetener saccharin was found to cause cancer in laboratory animals, many consumers stopped buying products that contained it. However, further studies revealed that the danger of saccharin had been overblown: there were no test done to determine the danger to human consuming saccharin, and the amounts of saccharin that the lab animals had ingested were more than any person could conceivably consume.

Consumer fear about saccharin eventually subsided, but food manufacturers found substitutes, and today much of the saccharin controversy is forgotten.

Human studies have been done with toluene but reproductive effects have been found only in cases where the person was highly over-exposed by sniffing toluene for a narcotic “high”

Although the reputation of toluene, has been tainted by the scrutiny, as technicians become more educated about chemicals and less fearful of them, they will choose products based on understanding and not trends of fear.

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