To Color Cotton Black. (Vääriä ja oikeita ohjeita)

Scientific American 34, 12.5.1849

To Color Cotton Black.

Put clear cold water into a tub, sufficient to cover the goods, then put into it two and a half ounces of chloride of lime, then put in the goods a half an hour—take out and wring, then fill a tub a second time with clear water, put into it two ounces of the sulphate of iron, put in the goods ten minutes, then lake out and wring; then put the sulphate of iron water into your dye kettle, and as much clear water as will cover the goods; then put in four ounces of the extract of logwood, one and a half ounce of the sulphate of copper, then boil in the goods from fifteen to thirty minutes.

NOTE.-After coloring, dip the cotton goods two or three times in the chloride of lime water, then wash well in hot strong soap suds and warm water.

Indigo Blue.—Pulverise two ounces of in­digo; put in eight ounces of sulphuric acid, in a pitcher; put the indigo into the acid—a little at a time, and keep stirring it with a stick until all the indigo is in the acid. Let this mixture stand eight hours before you color, then boil water sufficient to cover the goods. Put in the mixture of indigo and acid, then your goods immediately afterwards—let them boil five minutes. This is designed for woolen or silks.—Farmer and Mechanic.

Useful receipts are valuable, if correct, but if they are not correct they may be the means of doing much mischief. We copy the above receipts to point out their errors as some of our readers may chance to read them, and be led astray thereby. There are a great many receipts of a like character, which we see copied into various papers, just because they are receipts. The reason of this is, that there are not many who are sufficiently versed in practical chemistry to detect and point out un­scientific errors.

1st—The above receipt, will not color cot­ton black. The chloride of lime is not used for any purpose in the way of dyeing, it is on­ly used by Physicians and Chemists, in frigor­ific mixtures to produce intense cold by mix­ing it with snow.

The way to dye black in cotton is this;- Boil your cotton goods in clear water, then wring them, then let them steep twelve hours in sumach liquor, at the rate of 2½ pounds boiled or scalded for every 10 pounds of cotton goods. After this wring them out of the sumach and handle them evenly in lime water, (hydrate not chloride of lime) for 15 minutes, wring them out of this and handle them well for 15 minutes in a solution of copperas, (sulphate of copper,) at the strength of one pound of copperas to ten pounds of cotton, wring them out of this and air them well, then run them through a weak solution of lime water (very weak) and afterwards wash them well, and wring them—they are then ready for the logwood. A solution of warm boiled logwood, at the rate of 4 pounds (of the kinds now to be got,) should be allowed for every ten pounds of the cotton goods, if yarn. In this liquor they should be handled for halt an hour and afterwards dried.

We warrant this receipt to dye a good black on cotton goods, but there are some little things that can make it much faster, but the previous receipt is a burlesque on practical chemistry. Whoever heard of any person boiling cotton goods to dye a black, and then washing them in hot soap suds. Why the whole receipt is a compound of bleaching and dyeing mixed up together, producing the same effect in Chemis­try as it would in practical mechanics to work an engine by raising the steam and then let­ting it escape without going into the cylinder.

2d.—The Indigo blue produced by the sul­phate of indigo (chemic of the dyer,) is a fugitive color, it will not dye cotton, but by neutralizing the acid with chalk, but we warn every person from using it in the manner directed above, no silk goods should be boiled, in dyeing it would spoil the lustre of the silk.

The receipt which we have given for black will be valuable to many of our readers who have small jobs of coloring for home made clothes.

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