THE SCIENCE OF NAILS
Secret Ingredient: Nail Polish
From tosylamide/formaldehyde resin to stearalkonium bentonite, ingredient names can sound more like a top secret formula for NASA than a recipe for regular old nail polish. Each of these ingredients, however, has a purpose and plays a part in the overall performance of the polish.
Polish. We all use it. We all love it. But what exactly is it made of? From tosylamide/formaldehyde resin to stearalkonium bentonite, ingredient names can sound more like a top secret formula for NASA than a recipe for regular old nail polish. Each of these ingredients, however, has a purpose and plays a part in the overall performance of the polish.
Polish typically consists of four major types of ingredients:
1. POLYMERS make up the backbone of the polish, and they consist of two main chemicals, Tosylamide/Formaldehyde Resin (TSF Resin) and Nitrocellulose. These two work together to produce the characteristic hard shiny surface and strong adhesion that is typical in all polishes.
Nitrocellulose — a primary film former; it creates the hard shiny surface of polish but is brittle when used on its own; the polymer comes from cotton or wood chips by way of a chemical reaction of nitric and sulfuric acids.
Tosylamide/Formaldehyde Resin (TSF Resin) — a film former that works with nitrocellulose to reduce brittleness, improve adhesion, and create a more durable polish. (Note that this is not formaldehyde. Formaldehyde is a clear colorless gas that is not used in nail polish. You will never find formaldehyde listed as an ingredient in nail polish, but you will find it in some nail hardeners.)
2. PLASTICIZERS make the polish more flexible and increase its durability.
Dibutyl Phthalate (DBP) — an ingredient used to make nail polish more flexible, thus increasing its durability. This ingredient was controversially banned in the European Union as part of a sweeping ban of hundreds of chemicals. Many scientists feel the ingredient is safe; however, a number of American polish manufacturers have taken the chemical out of their formulations. Replacements for this ingredient are many and varied; common ones include a combination of trimethyl pentanyl diisobutyrate and triphenyl phosphate.
Camphor — an ingredient that increases flexibility and comes from the camphor tree.
3. PIGMENTS are used to create the color of each polish. A combination of naturally occurring and manufactured pigments are blended together to create varying shades.
Mica — a natural pigment that gives a shimmery look.
Silica — a thickening agent that prevents premature settling of pigments and lowers the gloss of polish.
Titanium Dioxide — an ingredient used to increase the opacity or “coverage” of polish; often used as a white pigment.
Bismuth Oxychloride — a special effect pigment that adds a pearlescent shimmer.
Citric Acid — a stabilizing agent produced from the fermentation of sugar cane and used to control the color of the pigment.
Other Common Pigments:
Ferric Ammonium Ferrocyanide
D & C Red #6 Barium Lake
D & C Red #7 Calcium Lake
FD & C Yellow #5 Aluminum Lake
4. SOLVENTS help make the polish spreadable. They keep the ingredients consistently dissolved in the polish during application, but slowly evaporate away after the polish has been applied. Solvents evaporate at different rates, so many solvents are used together to create an ideal evaporation time.
Ethyl Alcohol — a solvent used to dissolve the ingredients in the polish.
Isopropyl Alcohol — a solvent that helps prevent a possible explosion of nitrocellulose during shipment and storage; also used in rubbing alcohol and antibacterial gels.
Ethyl Acetate — a solvent that is manufactured from acetic acid (vinegar) and ethanol, and has a fruity odor. This solvent evaporates the fastest.
Propyl Acetate — a solvent manufactured from acetic acid and a mixture of propene and propane gases. This solvent evaporates the second fastest.
Butyl Acetate — a solvent manufactured from acetic acid and butanol, both of which can be produced via fermentation. This solvent evaporates the slowest.
Toluene — a solvent that controls the evaporation rate and the smoothness of the final coating; this solvent has encountered controversy because many feel it can cause liver and nervous system damage, while many others feel these fears are irrational and unfounded. Many polish manufacturers have removed this from their formulations.
Stearalkonium Bentonite — a thickening agent that controls flow during application and helps prevent rapid settling of pigments.
Benzophenone-1 — a UV-absorber that prevents color changes of the polish while in the bottle.
Dimethicone — a “drying agent” used to speed the drying of nail polish; usually the main ingredient found in nail polish dryers.