Priming the nail is the first, and in many ways, the most important step in acrylic liquid and powder application. Proper preparation of the nail plate, including the application of primer, can help eliminate product lifting. Improper use of primer could, however, wreak havoc on your client’s nails.

Whether you need nail primer, and how much, depends on the specific product application and the client. Materials such as linen, silk, and fiberglass do not usually require primer. For acrylic-based gels, primer use depends on the product and the client. Gene Packer, a chemist at California Chemical in Orange, Calif., says, “Primer is optional. Some clients need a primer, and others simply require bulling. And some products have more retention properties.” (Buffing removes oil and pterygium from the nail plate, substances that can hinder adhesion of adhesives and acrylic.)

A primer, regardless of what industry it’s used in, helps a product adhere to a surface. Primers etch a surface to allow a product or coating to seep in the cracks and grab hold.

A surface can be etched manually (for example, by filing) or with a liquid primer (as in nail primers). The acid in liquid etching primer does the work of the file. When you use an etching primer, you don’t need to sand the nail surface. You only need to remove the top layer of oil by buffing with a fine buffing file.

Primer Means “First Coat”

Where does primer come from? Primer gets its name because it is the first coat of many subsequent coats. Primers are used in many industries where the application of a coating is involved, such as the automotive industry (car paints), wall construction and improvement (paint, the, and grout), metallurgy, and ceramic industry (bakeware and cookware coatings).

Scientists call nail primer “surface priming material for proteinaceous substrates” (the “proteinaceous substrate” is the nail plate). This is important because primer in other industries is used to prepare non-biological surfaces. Nail primer (like many nail products) comes from the dental industry, where it was used to prepare dental surfaces for the application of denial bonding material (caps). Says Jesse Goldstein, president of Nails Direct in Engle-wood, N.J., “Primer has been used for 20 years in the dental industry.”

How Much Primer Is Necessary?

Is primer even necessary? Doug Schoon, executive director of Chemical Awareness Training Service in Newport Beach, Calif., says, “Conventional acrylic liquid and powder will stick to the nails without primer, but it won’t stick very well.”

The condition of your client’s nails determines whether and how much primer you need. Most manufacturers recommend a single application of primer. Clients with very oily nail beds and chronic lifting may need a second coat of primer. Some medications cause clients to have lifting problems, so those clients may need a second coat of primer.

It’s best to start with a minimum of primer and only use more if the client has developed lifting. If you’ve used two coats of primer and the client still develops lifting, your preparation and application technique — not the amount of primer — may be the problem. Says Schoon, “Don’t use primer as a crutch for poor technique.”

Primer Attracts Dissimilar Substances

So, we know where nail primer comes from, but how does it do its job?

A primer’s job is to join two surfaces that naturally do not slick together well. Polymerizing acrylic and the natural nail surface are two such surfaces.

Acrylic liquid and powder has a very high pH range (around 11), while the natural nail plate is slightly acidic (between 6 and 7). Acrylic liquid and powder are hydrophobic, that is, water-fearing, while the nail surface is hydrophylic, or water-loving. The nail surface is smooth, and so is acrylic, so acrylic requires something that will help it seep in to help it adhere.

The coating being applied is called the adherent. The surface is called the adherand. Primer-works like double-sided tape. Primer, both methacrylic acid and non-methacrylic acid types, is made up of molecules that have both hydrophylic and hydrophobic ends. Like sticky, double-sided tape, one end of the primer molecule attracts liquid and powder, while the other end attracts the nail surface.

Methacrylic Acid: Use As Directed

Michael Bannett, president of Cosmic in Sunrise, Fla., says, “True primer is methacrylic acid”. It’s been found to be very reliable for the nail industry because it is the right strength without being too harmful to be used on the nail, he says.

There are some negative side effects to primer, however, which is why some companies such of OPI Products in North Hollywood, Calif., formulated non-methacrylic acid versions. Methacrylic acid primer can burn the skin, it has a strong, unpleasant odor, and it can thin the nail plate.

If primer is corrosive, doesn’t that mean it is dangerous? Relatively speaking, the: answer is no. Schoon illustrates its safety this way: “Imagine two nail technicians. One uses methacrylic acid. She wears eye-goggles and gloves; the primer comes in a spill-proof bottle; her-salon is well-ventilated; and she applies the primer sparingly on the: nail surface only. The other nail technician uses non-methacrylic acid. She doesn’t wear gloves or eye goggles, her salon has little; ventilation, and she applies the primer sloppily. The primer that the first nail technician is using is many times safer than the one the second technician is using, because the first technician is limiting her and her client’s exposure to a safe level.”

The holes that are dug by primer are extremely small. Schoon doesn’t even like to say that primer “digs pits.” He prefers to describe primer this way: “It works like microscopic pieces of sandpaper to leave tiny nooks and crannies in the natural nail surface.” When the acrylic grabs the surface of the nail by flowing into the pits, it is called a mechanical retention.

Repriming the same area more than once doesn’t make the surface more “sticky.” In fact, over priming can damage the nail. Schoon says that the primer initially digs a little into the natural nail surface. Those holes stay there until the nail grows out. If you reprime the same area, the primer goes into the same holes and etches farther down into the nail surface. Reprime again, and the primer could make its way down into the nail surface. Reprime again, the the primer could make its way down as far as the delicate nail bed.

Methacrylic acid is found in nature in the oil of the Roman chamomile plant. The man-made version is a distant cousin to both methyl acrylate monomer and polymer (liquid and powder). Says Larry Gaertner of No Lift Nails (Garden Grove, Calif.), a primer pioneer, methacrylic acid works well as a nail primer for liquid and powder precisely because it is closely related chemically to liquid and powder.

In addition, says Gaertner, methacrylic acid is a super-dehydrator, which means it leaves the nail surface free of moisture and oil that could inhibit adhesion. It has this characteristic because it is a form of solvent.

Methacrylic acid varies from product to product in its concentration. Many nail primers are 100% pure methacrylic acid. These are the strongest, and therefore the most corrosive. Others are between 70-100% methacrylic acid. Solvents and buffers are added to lessen its corrosive a less, affect how it dries on the nail, and keep it shelf-stable.

Non-Methacrylic Acid Safer But Weaker

Non-methacrylic acid was originally developed for the veterinary industry. Various acrylate products had been used to repair split and fractured hooves. However, vets needed to prepare the hoof for the application of product by filing the area and applying acid primer. But it was difficult to reach split hoof areas in order to file, and acid primers were too dangerous to apply to the hoof because there was a danger that the acid would reach the animal’s bloodstream.

Non-methacrylic acid primer was the answer. It is not as corrosive as methacrylic acid. The amount of etching it does is many times less than the amount methacrylic acid does. Consequently, it is not as corrosive to the skin and can’t enter the bloodstream via the nail bed. However, the increased safety comes with a kiss in strength, says Schoon.

Non-methacrylic acid doesn’t work by etching the nail in order for the acrylic to grab hold of the nail surface. It works like a coat of adhesive. Non-methacrylic primer contains an ingredient that causes a temporary change in the pH of the natural nail (slightly acidic) to make it closer in pH to that of the product (highly alkaline). This pH change helps the product adhere. The nail eventually returns to its natural pH level, and the adhesive strength of the primer diminishes.

In order for it to be effective, you need to allow it to dry completely on the nail before applying product.

Says Adrea Nairne, president of Acu-Systems in Las Vegas, Nev., which markets several primers, “The non-methacrylic version is not as strong as the methacrylic, but it will do fine in many situations.”

The First Coat Should Dry Completely

Once yon apply primer on the nail, it begins to evaporate. When it has completely evaporated, the nail appears chalky white. The primer doesn’t dry white, it is the completely dry nail that looks white.

The: first coat of primer should be allowed to dry completely. If you apply a second coat, depending on the particular primer you’re using, you can either wait for the second coat to dry completely, or you can apply the product while the primer is still semi-wet. Schoon warns against applying product on wet primer because it can contaminate the product and cause yellowing, cracking, and bubbling. Non-methacrylic acid should be allowed to dry completely or its adhesive ability will be negated.

Dos and Don’ts of Primer

Here are some general guidelines for proper use of primer:

  • Wear safety glasses and gloves, use adequate ventilation, and avoid spills.
  • Keep MSDS close at hand.
  • Allow the first coat to dry completely. Do not apply product on wet primer. Allow non-methacrylic primer to dry completely before applying product.
  • Never apply more than two coats of primer.
  • Don’t apply primer on nail tips. It can crack ABS plastic.
  • Do not apply primer on the skin. Do not rub your eyes while applying primer (residue on your fingers could get in your eyes).
  • Avoid applying primer to the same area more than once. Repriming can thin the nail plate.


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