DE84974C - - Google Patents

Description

IMPERIAL

PATENT OFFICE.

PATENT LETTERING

CLASS 8: bleaching, dyeing, fabric printing and finishing

Patented in the German Empire on June 5, 1895.

In indigo dyeing, it is well known that real colors are achieved in light colors in every respect Tinting on wool only by pre-bluing the wool in the indigo vat and the following Translation with stains, especially for alizarin dyes.

This translation is done either in such a way that the blued wool is boiled with chromium potassium or chromium soda with the addition of suitable reducing agents I ¹ Z for ₂ to 2 hours and then colored with alizarin dyes, or it is dyed with alizarin dyes according to the method of DRP No. 70861, by translating the blued wool with certain alizarin dyes and then developing the nuances with fluorochrome additive.

Both methods have the great disadvantage that they involve considerable indigo losses are linked, as by boiling the blued wool in the pickling bath or in the Fluorochromic bath destroys or destroys a lot of indigo. is deducted.

The procedure of simmering and subsequent coloring also brings with it the problem with it that the quality of the wool suffers greatly from the prolonged simmering.

In addition there is the disadvantage that with this method it is very difficult to to achieve perfectly level colorations.

We have now succeeded in finding a method which can overcome all these inconveniences eliminated and delivers excellent results in the practical implementation.

If you boil the wool in the vat with chromic acid salts before it starts to turn blue, like chromium potassium or chromium soda, then put them in a lukewarm bath of a suitable one Reducing agent, preferably dilute acidic solutions of sulphurous acid salts, until the chromic acid is reduced to chromium oxide, the wool is in before the vat stained in such a way that, on the one hand, all dyes which attract chromium stain are colored can be, on the other hand, any harmful influence on the vat completely excluded is because the chromium is deposited on the fiber in the form of an oxide.

If you now bring the material into the hyposulfite or fermentation vat and blue to the desired depth, there is no loss of indigo during the subsequent coloring, and is certain of achieving the desired nuance, neither by doing so still hindered by the restriction to certain dyes.

Because the wool is evenly stained before it starts to blue and when it is re-stained even if the indigo does not come off unevenly, it becomes excellently even and level dyes, which because of the savings in indigo both, and it is also considerably cheaper to buy expensive pickling agents (such as tartar, oxalic acid) come as dyeings according to the usual methods of fast dyeing.

Examples.

I. For pure wool.
Color: stone gray. Regulation for 50 kg.

The well cleaned wool is in a boiling bath with 2 pCt. Chromkali ³ / stained ₄ hours, then, without rinsing in a second bath, which are added to water to 1000 1 2 to 3 1 sodium bisulfite, hantirt 20 to 30 minutes at a temperature of 50 ⁰ R.. Both bathrooms can still be used.

The wool is then rinsed and placed on the hyposulfite or fermentation vat after desired depth.

It is colored with:
ι Y ₄ kg alizarin brown in batter,
120 g alizarin orange in batter,
30 g Alizarin yellow GGW, powder.

The acetic acid can be added to the dyeing bath immediately.

To boiling drive _^3/4 hours ι γ, cooking hour; done.

II. For worsted yarn.
Color: fashion gray. For 50 kg.
The pickling operation is the same as above.

It is colored with:
300 g alizarin brown in batter,
30 g alizarin orange in batter,
15 g Alizarin yellow GGW, powder.

The acetic acid is added to the dyeing bath only after being driven to a boil and has cooked for about 20 minutes.

. ι Y cook for _{4 hours;} done.

III. For pallet fabric.
Color: fawn. For 50 kg.
Pickling operation as above. '

It is colored with:
2 kg alizarin brown in batter,
Y ₂ kg alizarin orange in batter,
25 g Alizarin yellow GGW, powder.

Treatment when staining as with comb

Claims (2)

PA te nt claims: ι. Process for the real dyeing of indigo blue wool, namely as loose wool, in spun threads and fabrics, consisting in first pickling the wool in a boiling bath with chromic acid salts, then treated with suitable reducing agents in a second bath, then in the Indigo vat whitewashed and finally with the dyes that are absorbed on the chrome stain is colored. 2. As a special embodiment of the method mentioned in claim 1 the use of lukewarm acidified solutions of sulphurous salts as reducing agents.