Spirit soluble Nigrosines, which are soluble in alcohol but not in water, are used in wood spirit stains to darken other colors. They are also used in polishes, black spirit varnishes, for staining leather, for printing calico and dyeing silk, and to produce shades that are bluish black in color. Quite often they are mixed with Chrysoidine R (spirit soluble), which is of a yellowish red color. The various brands of spirit-soluble Nigrosines which are sold are similar to Shultz’s No. 698.

Xanthene Colors

These colors form a group containing some of the most brilliant acid and basic dyes made and are, in general, faster to light than the triphenylmethane colors. These dyes are ideal for dyeing wood materials for items such as wood corner blocks, wood fireplace designs, and wood frames.

Anthracene or Anthraquinone Dyes

This large group contains 67 acid and mordant dyes, and includes the alizarines and 82 vat dyes. These colors are, in general, remarkable for great fastness to light. The anthraquinone class does not include any basic colors.

The “acid” colors of the group are numerous and important, and include:

o Alizarine Direct Blue, Violet, and Green
o Alizarine Sapphire, which is a reddish-blue dye that is very fast to light
o The German dyes
o Alizarine Irisol D and R
o Bright bluish violet wool and silk dyes, which are very fast to light
o Alizarine Emeraldol G ( which is a paste)
o A bluish green dye for wool and silk and is moderately fast to light
o Alizarine Astrol B and G, greenish blue, and very fast to light on wool and cotton
o Alizarine Rubinols, some of which are of a bluish red color and fast to light, while others are pink and salmon in hue and are used on dress goods, carpets, tapestry and designer window toppers, and door pediment.

Nitroso and Nitro Dyes

There are only a few nitroso colors and contain only “acid” and “mordant” dyes. The important acid water-soluble dye in the Nitroso group is often called Naphthol Green B. It comes in powder or paste form, is very fast to light, and is used as a wool dye, the coloring-matter being used in an acid bath containing an iron salt. Naphthol Green is also used in the manufacture of pigments. This color is a very useful yellowish green dye often recommended as a stain for wood finishing on items such as frieze boards, wood frames, and hardwood moulding because of its lightproof qualities.

The Nitro class is also small, containing several yellow acid dyes and a few mordant and pigment colors. The most important “acid” member of this class is generally named Naphthol Yellow S, but is sometimes known by other names such as Sulphur Yellow S, Acid Yellow, or Martius Yellow. It is used as a yellow color for silks and wool, and also is permitted as coloring matter in food in Australia and the United States. Victoria Yellow and Picric Acid also belong to this group.