Difference between revisions of "Eosin"

From CAMEO
Jump to navigation Jump to search
 
(One intermediate revision by the same user not shown)
Line 1: Line 1:
 +
[[File:MFA2018450 Eosin.jpg|thumb|Chinese drawing<br>MFA# 2018.450]]
 +
== Description ==
 
[[File:Eosin.jpg|thumb|Eosin]]
 
[[File:Eosin.jpg|thumb|Eosin]]
== Description ==
 
 
 
A red crystalline dye composed of the [[potassium]], [[sodium]], or [[lead]] salt of tetrabromofluorescein. First discovered by Caro in 1871, eosin is primarily used as an acid dye for producing a blood red color in [[silk]], [[wool]], [[paper]], [[leather]], and [[cotton]]. It is also used as a histological stain, a cosmetic colorant, and a colorant in red inks. In the late 19th and early 20th century, eosin was also used as a red paint pigment. Alcoholic solutions have a strong green [[autofluorescence]]. Eosin is not permanent and fades rapidly in sunlight.
 
A red crystalline dye composed of the [[potassium]], [[sodium]], or [[lead]] salt of tetrabromofluorescein. First discovered by Caro in 1871, eosin is primarily used as an acid dye for producing a blood red color in [[silk]], [[wool]], [[paper]], [[leather]], and [[cotton]]. It is also used as a histological stain, a cosmetic colorant, and a colorant in red inks. In the late 19th and early 20th century, eosin was also used as a red paint pigment. Alcoholic solutions have a strong green [[autofluorescence]]. Eosin is not permanent and fades rapidly in sunlight.
  
Line 11: Line 11:
 
== Risks ==
 
== Risks ==
  
Causes skin irritation. Fades rapidly in sunlight.   
+
* Causes skin irritation.  
 
+
* Fades rapidly in sunlight.   
Delasco: [https://www.delasco.com/content/sds/EOSIN-SDS.pdf SDS]
+
* Delasco: [https://www.delasco.com/content/sds/EOSIN-SDS.pdf SDS]
  
 
== Physical and Chemical Properties ==
 
== Physical and Chemical Properties ==
  
Soluble in ethanol.  Insoluble in water (potassium and sodium salts of eosin are water soluble).   
+
* Soluble in ethanol.  Insoluble in water (potassium and sodium salts of eosin are water soluble).   
 
+
* Maximum absorption wavelength = 520 nm.   
Maximum absorption wavelength = 520 nm.   
+
* Maximum emission wavelength = 540 nm.
 
 
Maximum emission wavelength = 540 nm.
 
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 32: Line 30:
 
|-
 
|-
 
! scope="row"| Melting Point
 
! scope="row"| Melting Point
| 300
+
| 300 C
 
|-
 
|-
 
! scope="row"| Molecular Weight
 
! scope="row"| Molecular Weight

Latest revision as of 07:30, 2 August 2022

Chinese drawing
MFA# 2018.450

Description

Eosin

A red crystalline dye composed of the Potassium, Sodium, or Lead salt of tetrabromofluorescein. First discovered by Caro in 1871, eosin is primarily used as an acid dye for producing a blood red color in Silk, Wool, Paper, Leather, and Cotton. It is also used as a histological stain, a cosmetic colorant, and a colorant in red inks. In the late 19th and early 20th century, eosin was also used as a red paint pigment. Alcoholic solutions have a strong green Autofluorescence. Eosin is not permanent and fades rapidly in sunlight.

Absorption spectrum

Synonyms and Related Terms

tetrabromofluorescein; Pigment Red 90; CI 45380; D&C Red No. 22; D&C Red No. 21; Acid Red 87; Solvent Red 43; éosine (Fr.); eosina (Esp., Port.); eosin Y; eosine A; eosine G; bromeosin; bromofluoresceic acid; geranium lake; eosine yellowish

Risks

  • Causes skin irritation.
  • Fades rapidly in sunlight.
  • Delasco: SDS

Physical and Chemical Properties

  • Soluble in ethanol. Insoluble in water (potassium and sodium salts of eosin are water soluble).
  • Maximum absorption wavelength = 520 nm.
  • Maximum emission wavelength = 540 nm.
Composition C20H8O5Br4
CAS 548-26-5
Melting Point 300 C
Molecular Weight Mol. wt. = 647.9

Resources and Citations

  • M.Ballard (ed.), Important Early Synthetic Dyes. Chemistry, Constitution, Date, Properties. Conservation Analytical Laboratory, Smithsonian Institution, 1991.
  • R. J. Gettens, G.L. Stout, Painting Materials, A Short Encyclopaedia, Dover Publications, New York, 1966
  • Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
  • Monona Rossol, The Artist's Complete Health and Safety Guide, Allworth Press, New York, 1994
  • The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983 Comment: entry 3639
  • Website: www.probes.com/handbook/sections - gives absorption max=524 and emission max=544
  • Website: member.pgonline.com/~bryand/dyes/45380.htm - absorption max = 516
  • Colour Index International online at www.colour-index.org Comment: discoverer and date
  • Sigma Dyes, Stains and Natural Pigments, Infrared Library, Nicolet, 1991-1995 Comment: OMNIC: formula= C20H8O5Br4, CAS= 548-26-5
  • The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998