Quinoline Yellow SS is a bright yellow
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 ...
with green shade. It is insoluble in water, but soluble in nonpolar organic solvents. Quinoline yellow is representative of a large class of quinophthalone pigments. It is suggested that quinoline yellow exhibits
excited-state intramolecular proton transfer Excited state intramolecular proton transfer (ESIPT) is a process in which photoexcited molecules relax their energy through tautomerization by transfer of protons. Some kinds of molecules could have different minimum-energy tautomers in different ...
(ESIPT) behavior and the behavior might be the cause of its decent photostability, by recent spectroscopic study.
Synthesis and reactions
As first described in 1878, the dye is prepared by the fusion of phthalic anhydride and
quinaldine
Quinaldine or 2-methylquinoline is an organic compound with the formula CH3C9H6N. It is one of the methyl derivatives of the heterocyclic compound quinoline. It is bioactive and is used in the preparation of various dyes. It is a colorless oil ...
. The compound exists as a mixture of two tautomers.
Using other anhydrides and other quinaldine derivatives other dyes in the quinophthalone family can be prepared.
When
sulfonated, it converts to a water-soluble derivative,
Quinoline Yellow WS
Quinoline Yellow WS is a mixture of organic compounds derived from the dye Quinoline Yellow SS (spirit soluble). Owing to the presence of sulfonate groups, the WS dyes are water-soluble (WS). It is a mixture of disulfonates (principally), monosu ...
.
Uses and safety
Quinoline Yellow SS is used in spirit
lacquer
Lacquer is a type of hard and usually shiny coating or finish applied to materials such as wood or metal. It is most often made from resin extracted from trees and waxes and has been in use since antiquity.
Asian lacquerware, which may be ca ...
s,
polystyrene
Polystyrene (PS) is a synthetic polymer made from monomers of the aromatic hydrocarbon styrene. Polystyrene can be solid or foamed. General-purpose polystyrene is clear, hard, and brittle. It is an inexpensive resin per unit weight. It is a ...
,
polycarbonate
Polycarbonates (PC) are a group of thermoplastic polymers containing carbonate groups in their chemical structures. Polycarbonates used in engineering are strong, tough materials, and some grades are optically transparent. They are easily work ...
s,
polyamide
A polyamide is a polymer with repeating units linked by amide bonds.
Polyamides occur both naturally and artificially. Examples of naturally occurring polyamides are proteins, such as wool and silk. Artificially made polyamides can be made through ...
s,
acrylic resin
186 px, Polyhydroxyethylmethacrylate is a typical acrylate resin.
An acrylic resin is a thermoplastic or thermosetting plastic substance typically derived from acrylic acid, methacrylic acid and acrylate monomers such as butyl acrylate and or me ...
s, and to color
hydrocarbon
In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and hydrophobic, and their odors are usually weak or ex ...
solvents. It is also used in externally applied drugs and cosmetics. Quinoline Yellow SS is used in some yellow
colored smoke
Colored smoke is a kind of smoke created by an aerosol of small particles of a suitable pigment or dye.
Colored smoke can be used for smoke signals, often in a military context. It can be produced by smoke grenades, or by various other pyrote ...
formulations.
It may cause
contact dermatitis
Contact dermatitis is a type of acute or chronic inflammation of the skin caused by exposure to chemical or physical agents. Symptoms of contact dermatitis can include itchy or dry skin, a red rash, bumps, blisters, or swelling. These rashes are ...
. It has the appearance of a yellow powder with a melting point of .
References
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Quinoline dyes
Staining dyes
Solvent dyes
Indandiones