Arylide yellow

Arylide yellow
Color coordinates
Hex triplet	#E9D66B
sRGB B (r, g, b)	(233, 214, 107)
HSV (h, s, v)	(51°, 54%, 91%)
CIELChuv (L, C, h)	(85, 71, 76°)
Source
ISCC–NBS descriptor	Brilliant greenish yellow
B: Normalized to [0–255] (byte)

Arylide yellow, also known as Hansa yellow and monoazo yellow, is a family of organic compounds used as pigments. They are primarily used as industrial colorants including plastics, building paints and inks. They are also used in artistic oil paints, acrylics and watercolors. These pigments are usually semi-transparent and range from orange-yellow to yellow-greens. Related organic pigments are the diarylide pigments. Overall, these pigments have partially displaced the toxic cadmium yellow in the marketplace. Painters such as Alexander Calder and Jackson Pollock are known to have employed arylide yellow in their artworks. ^[1]

Production

The compound is obtained by azo coupling of aniline and acetoacetanilide or their derivatives. The class of compounds was discovered in Germany in 1909. The initially formed diazo compound tautomerizes to give a ketohydrazone, which features extended pi-conjugation. ^[2]

formation of Hansa pigments by diazotization followed by tautomerization

Examples

Members of this class include:

• Pigment Yellow 6 (CAS# 2512-29-0), derived from 2-nitrotoluene (diazonium precursor) and aniline (acetoacetanilide precursor) to produce medium yellows.
• Pigment Yellow 3, derived from 4-chloro-2-nitroaniline (diazonium precursor) and 2-chloroaniline (acetoacetanilide precursor) to produce greenish-yellows.
• Pigment Yellow 61 a lake pigment
• Pigment Yellow 74, derived from 2-methoxy-4-nitroaniline (diazonium precursor) and 2-methoxyaniline (acetoacetanilide precursor) to produce greenish-yellows.
• Pigment Yellow 97, which contains the phenylaminosulfonyl substituent, which confers particularly high fastness.

Artists Pigments

Several monoazo yellows are used as artists' pigments, frequently marketed under the names 'Hansa' or Arylide. ^[3] These include:

• PY1 ^[4]
• PY2 ^[5]
• PY3 Hansa Yellow Light or Lemon Yellow ^[6]
• PY4 ^[7]
• PY5 ^[8]
• PY6 ^[9]
• PY10 ^[10]
• PY60 ^[11]
• PY65 Hansa Yellow Deep or Indian Yellow ^[12]
• PY74 Hansa Yellow Medium or Primary Yellow ^[13]
• PY82 ^[14]
• PY97 Hansa Yellow Medium or Hansa Yellow Deep ^[15]

See also

• List of colors

References

1. Arylide Yellow, Colourlex
2. K. Hunger. W. Herbst "Pigments, Organic" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2012. doi : 10.1002/14356007.a20_371
3. "Synthetic organic pigments - Monoazo (arylide)". Handprint. 1 August 2015.
4. "PY1 Hansa Yellow G". Artist Pigments.
5. "PY2 Hansa Yellow GR". Artist Pigments.
6. "PY3 Hansa Yellow 10G". Artist Pigments.
7. "PY4 Hansa Yellow 10G". Artist Pigments.
8. "PY5 Hansagelb 5G". Artist Pigments.
9. "PY6 Hansa Yellow 3G". Artist Pigments.
10. "PY10 Hansa Yellow R". Artist Pigments.
11. "PY60 Hansa Yellow 4R 3D—1750". Artist Pigments.
12. "PY65 Hansa Yellow 3RN". Artist Pigments.
13. "PY74 Arylide Yellow 5GX". Artist Pigments.
14. "PY82 Hansagelb 8G". Artist Pigments.
15. "PY97 Diarylide Yellow FGL". Artist Pigments.

Further reading

• Microstructural Characteristics of Paint Pigments
• A Deep Technical Insight On Arylide Yellow Organic Pigments
• Arylide Yellow GY - Pigment Yellow 74 Industries Details