Chem

Alex Civitano Ms. Forster College Chemistry P7 3/3/11 What is the chemistry of tattoos' The short and sweet answer to this question is that we cannot be fully sure about what is in the ink of a tattoo. The manufacturers of inks and pigments are not required to reveal the contents in the inks. A professional who mixes their own inks from dry pigments will be most likely to know the composition of the inks. However, they would much rather keep the information is a secret because if they have a mixture that is coming out pleasing to the eye, others would want to get their hand on the inks. So, as a barrier of competiveness, the ingredients are usually kept secret. Anyways, most tattoo inks technically aren't even inks. The “inks” are composed of pigments that are suspended in a carrier solution. Although it is very popularly believed to be true, pigments usually are not vegetable dyes. Today's pigments primarily are metal salts. However, some pigments are plastics and there are probably some vegetable dyes too. The pigment provides the color of the tattoo. The purpose of the carrier is to disinfect the pigment suspension, keep it evenly mixed, and provide for ease of application. As for the chemistry of tattoos, they have seemed to differ as time passes. The oldest pigments came from using ground up minerals and carbon black. Today's pigments include the original mineral pigments, modern industrial organic pigments, a few vegetable-based pigments, and some plastic-based pigments. Allergic reactions, scarring, phototoxic reactions, which is a reaction from exposure to light, especially sunlight, and other different effects are possible with many pigments. The plastic-based pigments are very intensely colored, but many people have reported reactions to them. There are also pigments that glow in the dark or in response to black ultraviolet light. These pigments are well-known to be risky. Some may be safe, but others are radioactive or in other words, toxic. Tattoo ink consists of pigment and a carrier. The carrier may be a single substance or a mixture. The purpose of the carrier is to keep the pigment evenly distributed in a fluid matrix, to inhibit the growth of pathogens, to prevent clumping of pigment, and to aid in application to the skin. Among the safest and most common ingredients used to make the liquid are ethyl alcohol (A.K.A. Ethanol), purified water, witch hazel, Listerine, propylene glycol, and glycerine (A.K.A. Glycerol). These are not the only ingredients used. There are many others such as denatured alcohols which are toxic and can sometimes burn the skin, other alcohols like methyl alcohol (A.K.A.methanol) and isopropyl alcohol or rubbing alcohol are commonly used, even though they are toxic. Also used are ethylene glycol, more commonly known as antifreeze which is toxic, aldehydes like formaldehyde and gluteraldehyde which are both extremely toxic and various surfactants or detergents. There are many other substances that could be found in an ink. A tattooist has the choice of mixing his or her own ink like when mixing dry dispersed pigment and a carrier solution or purchasing what are called predispersed pigments. Many predispersed pigments are as safe or safer than inks mixed by the tattooist. However, the ingredient list are not required to be disclosed, so any chemical could be present in the ink. The best and safest thing to do is to make sure the ink supplier and the particular ink has a long history of safety. When using the word 'toxic' with many of the substances above, that is just a generalization. Some of these chemicals are mutagens, carcinogens, teratogens, and toxins. Simply put, some of these “participate” in other reactions in the body. Some of them may not even show up for decades! To get the many different colors of a tattoo, there are many different materials in each one of them. In order to make a black pigment, materials used are Iron Oxide (Fe3O4) , Iron Oxide (FeO) , Carbon, and Logwood. Natural black pigment is made from magnetite crystals, powdered jet, wustite, bone black,and amorphous carbon through combustion. In order to make a brown pigment, the material ochre is used. Ochre is composed of iron oxides (Fe3O4) mixed with clay. Raw ochre is yellowish. When dehydrated through heating, ochre changes to a reddish color. Those colors are then mixed to make a brownish color. In order to make the color red, the materials that are used are Cinnabar (HgS) , Cadmium Red (CdSe), and Iron Oxide (Fe2O3) . Iron oxide is also commonly known as rust. Cinnabar and cadmium pigments are highly toxic. Fewer reactions have been reported with naphthol red than the other pigments, but all reds carry risks of allergic or other reactions. In order to make the color orange, the materials used are disazodiarylide and disazopyrazolone, and cadmium seleno-sulfide. The organics are formed from the condensation of two monoazo pigment molecules. They are large molecules with good thermal stability and colorfastness. In order to get the natural flesh color, ochres are used which is just iron oxides mixed with clay. In order to make the color yellow, Cadmium Yellow (CdS, CdZnS), Ochres, Curcuma Yellow, Chrome Yellow (PbCrO4 which is often mixed with PbS), and disazodiarylide are used. Curcuma is derived from plants of the ginger family; Reactions are commonly associated with yellow pigments, in part because more pigment is needed to achieve a bright color. In order to achieve the color green, used are Chromium Oxide (Cr2O3), Malachite [Cu2(CO3)(OH)2] Ferrocyanides and Ferricyanides, Lead chromate, Monoazo pigment, Copper and Aluminum Cu/Al. The greens often include admixtures, such as potassium ferrocyanide (yellow or red) and ferric ferrocyanide (Prussian Blue). In order to make the color white, used are Lead White or Lead Carbonate, Titanium dioxide (TiO2), Barium Sulfate (BaSO4), and Zinc Oxide. Some white pigments are derived from anatase or rutile. White pigment may be used alone or to dilute the intensity of other pigments. Titanium oxides are one of the least reactive white pigments. The chemistry of tattoos is very interesting and can have all sorts of different answers. The makeup of the colors is amazing because of how many different elements it could have just to make one “simple color”. Now I know that before I would like to get my first tattoo, I might think twice about what the tattoo artist is using in the ink that will go onto my body. Iron Oxide (Fe3O4)Cinnabar (HgS)Cadmium Red (CdSe)Iron Oxide (Fe2O3) Cadmium Yellow (CdS) Chrome Yellow (PbCrO4, PbS)Chromium Oxide (Cr2O3) Malachite [Cu2(CO3)(OH)2]Titanium dioxide (TiO2)Barium Sulfate (BaSO4)