The condensation product of b-naphthol above referred to precipitates gelatine and aniline hydrochloride and gives a brown coloration with ferric chloride.
Naphthol condensed with hydrochloric acid and formaldehyde yields a methylenedinaphthol, which is insoluble in water; the sodium salt, however, easily dissolves.
Some of these take the form of special preparations of the colour manufacturers, and are sold as naphthol D, naphthol X, red developer C, etc.
Those most in use are beta-naphthol for red from Primuline, and for bluish blacks from Diamine blacks, Diazo blacks, Zambesi blacks, etc.
Various preparations of beta-naphthol have been brought out by colour makers.
For this colour the cotton is prepared with the beta-naphthol in the ordinary way.
They are also called naphtholcolours from the use of beta-and alpha-naphthol in their production.
The beta-naphthol bath does not keep well and in time tends to grow brown, and when this occurs stains are invariably produced on the cotton.
A large number of the dyes prepared from coal tar are called azo colours, such for instance are the Biebrich and Croceine scarlets and oranges, Naphthol black, Congo red, etc.
The cotton is treated in this way as with the ordinary beta-naphthol preparation.
The cotton is prepared with beta-naphthol in the usual way, and then passed through this developing bath.
The diazo solution was poured into a solution of 3 grams B-naphthol in 8 grams of NaOH and 60 cc.
The addition of [beta]-naphthol to naphthalene raises the freezing point of the latter, and the rise is directly proportional to the amount of naphthol added.
Bead Holliday & Sons; theNaphthol and Naphthylamine Blacks of Leopold Cassella & Co.
Naphthol Yellow, for instance, only imparts a very faint shade of yellow when thus dyed, and this is easily removed by boiling-water treatment.
Indigo extract, Cochineal, Acid Magenta, Picric acid, Naphthol Yellow, and Tartrazine dye the wool only at the boil.
Many of the black dyes--Naphthol Black, Naphthylamine Blacks, (p.
The Naphthol Blacks will also be found useful in the same way, while the greys from Anthracene Chrome Blacks and the Alizarine blacks are very good and fast.
The basic preparation is Phecolates, which contains bile salts in combination with phenyl salicylates and benzo-naphthol in about one-eighth the regular doses and hence not likely to be of any real service.
Naphthol Yellow is of course a naphthol colour, whilst Vermilline Scarlet is a dye containing both naphthylamine and naphthol.
From naphthalene, either naphthylamine (a body like aniline) or naphthol (resembling phenol) may be prepared.
The azo-blacks are obtained by combining diazotised sulpho-acids of amidoazo-compounds of the benzene or naphthalene series with naphthol sulpho-acids or other naphthalene derivatives.
Beta-naphthol violet, the first of the oxazines, discovered by the writer; followed in 1881 by gallocyanin.
The bases of the third column when diazotised and combined with the disulpho-acids of beta-naphthol give a graduated series of dyes beginning with orange and ending with bluish scarlet.
In this same year, 1879, it was found that by heating nitrosodimethylaniline with beta-naphthol in an appropriate solvent, a violet colouring-matter was formed.
Naphthol Green, the Oxazines, and the Indophenols, 161.
A salt of this last acid, containing sodium and iron as metallic bases, was introduced in 1884, under the name of "naphthol green.
If it deflagrates with coloured fumes, the dye is aurantia, naphthol yellow S.
If there is no change, we have naphthol yellow, auramine, azoflavine, orange II.
Puncture with nails and such things, especially if rusty, should be squeezed and washed with sulphur-naphthol or hot water poured into the hole.
Both the formaldehyde and the naphthol exercise tanning actions, but the process is not used in practise.
The process is similar to the production of the Insoluble Azo Colours, the [beta]-naphthol which is there applied to the fibre being here replaced by a Direct Colour.
The only developer of any practical importance is a solution of [beta]-naphthol in caustic soda, which produces primuline red.
The colour obtained varies according to the particular diazo compound, as well as the amine or phenol employed, [beta]-naphthol being the most useful among the latter.
A large vessel is needed for the reaction, as the nitroso-b-naphthol separates in a finely divided condition and there is some tendency to foam.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "naphthol" in a variety of sentences. We hope that you will now be able to make sentences using this word.
