A solvent dye is a

dye A dye is a colored substance that chemically bonds to the substrate to which it is being applied. This distinguishes dyes from pigments which do not chemically bind to the material they color. Dye is generally applied in an aqueous solution an ...

soluble in

organic solvent A solvent (s) (from the Latin '' solvō'', "loosen, untie, solve") is a substance that dissolves a solute, resulting in a solution. A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid. Water is a solvent for p ...

s. It is usually used as a solution in an organic solvent. Solvent Dye
/ref> Solvent dyes are used to color organic solvents, hydrocarbon fuels,

wax Waxes are a diverse class of organic compounds that are lipophilic, malleable solids near ambient temperatures. They include higher alkanes and lipids, typically with melting points above about 40 °C (104 °F), melting to giv ...

es,

lubricant A lubricant (sometimes shortened to lube) is a substance that helps to reduce friction between surfaces in mutual contact, which ultimately reduces the heat generated when the surfaces move. It may also have the function of transmitting forces, t ...

plastic Plastics are a wide range of synthetic or semi-synthetic materials that use polymers as a main ingredient. Their plasticity makes it possible for plastics to be moulded, extruded or pressed into solid objects of various shapes. This adaptab ...

s, and other hydrocarbon-based nonpolar materials.

Fuel dyes Fuel dyes are dyes added to fuels, as in some countries it is required by law to dye a low-tax fuel to deter its use in applications intended for higher-taxed ones. Untaxed fuels are referred to as "dyed", while taxed ones are called "clear" or "w ...

are one use of solvent dyes. Their molecules are typically

nonpolar In chemistry, polarity is a separation of electric charge leading to a molecule or its chemical groups having an electric dipole moment, with a negatively charged end and a positively charged end. Polar molecules must contain one or more polar ...

or little polar, and they do not undergo ionization. They are insoluble in water. They form a colloidal solution in solvents. They have poor (basic dyes) to good (metal complex based) light fastness. Solvent dyes are used for gold imitation (and other transparent metallic effects) of metallized polyester films. Also used in marking inks, inkjet inks, glass coloration, and so on. Names of solvent dyes are often generic, of the scheme "solvent <color> <number>", e.g.

Solvent Red 24 Sudan IV (C24H20N4O) is a lysochrome (fat-soluble dye) diazo dye used for the staining of lipids, triglycerides and lipoproteins on frozen paraffin sections. It has the appearance of reddish brown crystals with melting point 199 °C and maxi ...

Solvent Red 26 Solvent Red 26, also known as Oil Red EGN or C.I. 26120, is a purplish red synthetic azo dye. It is soluble in oils and insoluble in water. Its main use is as a standard fuel dye in the US mandated by the US IRS The Internal Revenue Ser ...

Solvent Red 164 Sudan III is a lysochrome (fat-soluble dye) diazo dye. It is structurally related to azobenzene. Uses It is used to color nonpolar substances such as oils, fats, waxes, greases, various hydrocarbon products, and acrylic emulsions. Its main ...

Solvent Yellow 124 Solvent Yellow 124 is a yellow azo dye used in European Union as a fuel dye. It is a marker used since August 2002 to distinguish diesel fuel intended for heating from a higher-taxed motor diesel fuel. It is added to fuels not intended for motor v ...

Solvent Blue 35 Oil Blue 35 is a blue anthraquinone dye used for colouring alcoholic and hydrocarbon based solvents, including oils, fats, and waxes. It is used also in lacquers and inks. In some countries, it is used as a fuel dye. It is also used in some blue ...

, etc. Red and yellow solvent dyes are often

azo dye Azo dyes are organic compounds bearing the functional group R−N=N−R′, in which R and R′ are usually aryl and substituted aryl groups. They are a commercially important family of azo compounds, i.e. compounds containing the C-N=N ...

s, green and blue ones tend to be

anthraquinone dyes Anthraquinone dyes are an abundant group of dyes comprising a anthraquinone unit as the shared structural element. Anthraquinone itself is colourless, but red to blue dyes are obtained by introducing electron donor groups such as hydroxy or amino ...

References

{{Dyeing Dyes