phthalic acid

noun

1. Chemistry. any of three isomeric acids having the formula C 8 H 6 O 4 , especially the ortho isomer orthophthalic acid, a colorless, crystalline, slightly water-soluble solid used chiefly in the manufacture of dyes, medicine, and perfume.
2. isophthalic acid.
3. terephthalic acid.

phthalic acid

/ ˈfθæl-; ˈθælɪk /

noun

1. a soluble colourless crystalline acid used in the synthesis of dyes and perfumes; 1,2-benzenedicarboxylic acid. Formula: C 6 H 4 (COOH) 2

phthalic acid

/ thăl′ĭk,fthăl′- /

1. A colorless, crystalline organic acid prepared from naphthalene and used in the synthesis of dyes, perfumes, and other organic compounds. Chemical formula: C 8 H 6 O 4 .

Word History and Origins

Origin of phthalic acid¹

First recorded in 1855–60

Word History and Origins

Origin of phthalic acid¹

C19 phthalic, from phthal- (see phthalein ) + -ic

Example Sentences

Thus benzoic acid is the carboxyl-derivative of benzene, and the phthalic acid with which we are now concerned is a dicarboxyl-derivative of benzene.

From Project Gutenberg

An important oxidation synthesis of aromatic acids is from hydrocarbons with aliphatic side chains; thus toluene, or methylbenzene, yields benzoic acid, the xylenes, or dimethyl-benzene, yield methyl-benzoic acids and phthalic acids.

From Project Gutenberg

Resorcinol is a phenolic derivative of benzene containing two hydroxyl groups; it is therefore related to phenol in the same way that diamidobenzene is related to aniline or phthalic acid to benzoic acid.

From Project Gutenberg

One of these compounds, phthalic acid, is obtained from naphthalene, and the other, resorcin or resorcinol, is prepared from benzene.

From Project Gutenberg

Three isomeric phthalic acids are known, but only one of these is of use in the present branch of manufacture.

From Project Gutenberg