Lithol red

Description

[BASF] A trademark for a series of bright red, metallic salts of a synthetic Azo dye. First patented in 1899 by Paul Julius (BASF), Lithol reds are made by combining Tobias acid (2-naphthylamine-1-sulfonic acid) and beta-naphthol. Variations in colors are obtained by forming the salts with Sodium, Barium, Calcium, and Strontium cations. Lithol reds are inexpensive and widely used in printing inks, crayons, enamels, stationery, and industrial paints. They are also used as a colorants in some plastics. Lithol reds are not lightfast in sunlight and have only been used in student grade artists paints.

- Na salt: yellowish red, PR 49, CI 15630, water soluble 

- Ba salt: bluish pink, PR 49:1, CAS 1248-18-6

- Ca salt: bright red, PR 49:2, CAS 1103-38-4

- Sr salt: purplish red, PR 49:3, CAS 1103-39-5

Synonyms and Related Terms

Lithol toner; Pigment Red 49; CI 15630; 1-sulfo-beta-naphthalene-azo-beta-naphthol; Harrison Red

FTIR Ba (MFA)

FTIR Ca red(MFA)

FTIR Ca maroon(MFA)

Comparisons

Pigment number	Manufacture	Pigment name	Manufacture CI number	Comments
PY013	Sun	diarylide AAMX yellow_rs	275-1149
PY014	Sun	diarylide AAOT yellow	274-1744	FTIR spectra appear the same for all PY014
PY014	Magruder	diarylide yellow AAoT t-p lumps	ya1161-lu	FTIR spectra appear the same for all PY014
PY014	Magruder	diarylide yellow AAoT s_o	ya1283-dc	FTIR spectra appear the same for all PY014
PY017	Sun	diarylide AAOA yellow	275-0023
PO034	Sun	diarylide tolyl orange	282-0034
PY083	Magruder	diarylide yellow	yr1300-dc	FTIR spectra are the same for Sun and Magruder PY083
PY083	Sun	diarylide AADMC yellow	275-0570	FTIR spectra are the same for Sun and Magruder PY083

Other Properties

Poor lightfastness

Composition	C20H14N2O4S

Hazards and Safety

May cause allergic reactions. May be contaminated with cancer causing chemicals.

Additional Information

º H. A. L. Standeven, "The History and Manufacture of Lithol Red, A Pigment Used by Mark Rothko in his Seagram and Harvard Murals of the 1950s and 1960s" Tate Papers, Issue 10, 2008. Link

º B.Berrie, S.Q.Lomax, "Azo Pigments: Their History, Synthesis, Properties and Use in Artists' Materials" in Studies in the History of Art, No.57, National Gallery of Art, Washington DC, 1997.

Sources Checked for Data in Record

• R. J. Gettens, G.L. Stout, Painting Materials, A Short Encyclopaedia, Dover Publications, New York, 1966

• Ralph Mayer, A Dictionary of Art Terms and Techniques, Harper and Row Publishers, New York, 1969 (also 1945 printing)

• Art and Architecture Thesaurus Online, http://www.getty.edu/research/tools/vocabulary/aat/, J. Paul Getty Trust, Los Angeles, 2000

• B. Berrie, S.Q. Lomax, 'Azo Pigments: Their History, Synthesis, Properties and Use in Artists' Materials', Studies in the History of Art , National Gallery of Art, Washington DC, No. 57, 1997

• Thomas Gregory, The Condensed Chemical Dictionary, Reinhold Publishing, New York, 3rd ed., 1942

• Michael McCann, Artist Beware, Watson-Guptill Publications, New York City, 1979