Acid red 88 is an

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 ...

. Due to its intense colour, solid samples appear almost black. It is used to dye cotton textiles red. A closely related acid dye is

Acid Red 13 Acid Red 13 is an 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. com ...

Preparation and use

It can be obtained by azo coupling of naphthionic acid and 2-naphthol. Instead of crystallising, it

vitrifies Vitrification (from Latin ''vitreum'', "glass" via French ''vitrifier'') is the full or partial transformation of a substance into a glass, that is to say, a non-crystalline amorphous solid. Glasses differ from liquids structurally and glasses pos ...

when cooled or salted out of the solution. : naphthol_red_preparation

This compound is used in the textile industry as a dye. It can also be used for research in photocatalysis (as degradation object).

References

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External links

echo Chemical Database: 1-Naphthalenesulfonic acid, 4-((2-hydroxy-1-naphthalenyl)azo)-, monosodium salt (EnvironmentalChemistry.com)
This page contains information on the chemical 1-Naphthalenesulfonic acid, 4-((2-hydroxy-1-naphthalenyl)azo)-, monosodium salt including: 72 synonyms/identifiers. Azo dyes 2-Naphthols