WOAD,

DI

der, which is insoluble in water. There are two ways of dyeing with Indigo. It may be dissolved in sulphuric acid or oil of vitriol, thereby making an indigo extract.

deprived of its oxygen. The deoxidized indigo is yellow and in this state penetrates the woollen fibre; the more perfectly the indigo in a vat is deoxid

EXTRACT

itriol (pure,

ely groun

recipitat

ll all is used up. This should take an hour or two. Stir a few times each day for 4 or 5 days, adding about 1/2 oz. more of cha

ACT (4 to 6

iling for another 1/2 hour. By keeping it below boiling point while dyeing, better colours are got, but it is apt to be uneven. Boiling levels the colour but makes the shade greener. This is corrected by adding to the dye bath a litt

AT (TIN)

ound up 1/2 oz. tin, Stannous Chloride, in a little lime water and add, together with 1/2 oz. zinc. Add more lime water or tin according to the state

ITE-SODA V

powdere

austic Soda so

um Hydrosulp

0 minutes. Empty into a saucepan, capacity 1 gallon. Take 12 fluid ozs. of water adding gradually 3 ozs. of commercial caustic soda 76 per cent

be weighed beforehand and the stock of the same be kept free from damp air, or great heat, for future vats the hydrometer can be dispensed with; it i

stand for half an hour, then test with a strip of glass. This should show a perfectly clear golden yellow colour (turning blue in 45 secs. approx.), free from spots. If dark spots show, this indicates undissolved indigo, therefore gradually add hydrosulphite solution (2-3 fluid ozs.). Wait 15 mins. and test

y, let it stand for 20 minutes; this renders harmless any undissolved oxygen. Add a small cupful of the Stock Solution, stir carefully without splashing.

s. of hydrosulphite and warm up to 140°F. and wait 30 minutes. As a last resort add caustic soda

washing and rubbing. The yarn must be oxidized by exposure to the air for the same length of time as dipped. After the final dip, pass the yarn through a 10

f Defective I

through bad management of the vats, the yarn is dull, pass the yarn through a hot bath (100% water, 1% acetic acid) and wash in two waters. If yarn is streaky, tak

acts should be

he alkali which disso

es the Indigotine in th

arn as Indigo White and on exp

yellow or a greenish blue. The latter is for blue yarn and s

thing to have hydrosulphite slightly in excess as this prevents premature oxid

with the greatest caution or the

oured it is impossible to obtain a clear

re in using vegetable Indigo do not add all the Caustic or Hydros

O

ur which changes to a deep blue in the air. It is said to be inferior in colour to indigo but the colour is much more permanent. The leaves when cut are reduced to a paste, kept in heaps for about fifteen days to ferment, and then are formed into balls which are dried in the sun; these have a ra

ntly with hydrochloric acid, yield a good indigo blue. If the time of infusion be increased, greens and browns are obtained. It is supposed that woad was "vitrum" the dye with which Caesar said almost all the Britons stained their bodies. It is sa

GW

mpeche, Cam

lose all its brightness when exposed to the air. But with proper mordants and with careful dyeing this dye can produce fast and good colours. Queen Elizabeth's government issued an enactment entirely forbidding the use of log

r DYEING w

. B

1 per cent Sulphuric Acid. Wash and dye in separate bath for 1

y adding 5 per cent F

adding 3 to 4 per cent Alum to the mordanti

per cent Stannous Chloride to the dye b

LAV

dder, 1 per cent logwood. Enter the wool, raise to the boil and boil for 45 minutes. The pro

AST LOGW

. Make a bath of 15 to 20 per cent logwood with about 3 per cent chalk added to it. Boil the wool for 1 hour, wash and

EN GREY

ras, and work it at boiling heat for 1/2 hour. Then wash. In another copper, boil 50 per cent logwood chips for 20 mi

ED PURPLE W

r cent cream of tartar for 1 hour. Let cool in the

a separate bath and pour through a sieve into the dye bath. Enter the wool when warm

PU

. tartar for one hour; wring out and put away in a ba

TNO

s used alone, a mord