APPENDIX D.

The following Lists of Colours have been furnished by Mr. M. C. Lamb, Director of the Leather Dyeing Department of Herold’s Institute, London, who has devoted much time to testing the various dyes with regard to their permanence and suitability for leather. Many of the colours have also been tested and found satisfactory in the Leather Department of the Yorkshire College. The following abbreviations of makers’ names are used in the lists:—

B.Basler Chemische Fabrik, A. G. Basle, Switzerland.
B.A.S.F.Badische Anilin und Soda Fabrik. Ludwigshafen a. Rhine, Germany.
Ber.Berlin Aniline Co. Berlin S.O., Germany.
B.S. Spl.Brooke, Simpson & Spiller. Atlas Dye Works, Hackney Wick, London, N.E.
By.Farben-fabriken, late Bayer & Co. Elberfeld, Germany.
C.L. Cassella & Co. Frankfort a. Main, Germany.
C.A.French Aniline Colour Works. Vieux-Conde (Norde), France.
C. & R.Claus & Rée. Clayton, near Manchester.
D.Dahl & Co. Barmen, Germany.
D. & H.Durand, Huguenin & Co. Basle, Switzerland.
G.R. Geigy & Co. Basle, Switzerland.
Ger.Gerber & Co. Basle, Switzerland.
K.Kalle & Co. Bierbrich a. Rhine, Germany.
Leon.A. Leonhardt & Co. Muhlheim a. Main, Germany.
LeitchJ. W. Leitch. Milnsbridge Chemical Works, Huddersfield.
Lev.Levinstein Ltd. 21 Minshull Street, Manchester.
M.L.B.Meister, Lucius & Bruning. Hoechst a. Main, Germany.
Mo.Gilliard, P. Monnet & Gartier. Lyons, France.
N.Noetzel, Istel & Co. Griesheim a. Main, Germany.
O.K. Oehler & Co. Offenbach a. Main, Germany.
P.St. Denis Dyestuff Co., late Pourier. St. Denis, near Paris.
R.Sociéte Chimique des Usines du Rhone. Lyons, France.
R. H. & S.Read, Holliday & Sons. Huddersfield.
S.C.Ind.Society of Chemical Industry. Basle, Switzerland.
Uer.Chemische Fabriken. Uerdingen a. Rhein, Germany.
W. Bros.Williams Bros. & Co. Hounslow, Middlesex.

STAINING.

Single Acid Dyes suitable for Staining Vegetable Tanned Leather.
Browns.
Yellows.
Reds and Oranges.
Greens.
Violets.
Blues.
Single Basic Dyes
suitable for Staining Vegetable Tanned Leather.
Browns.
Yellows.
Greens.
Reds.
Violets.
Blacks.

DYEING.

Single Acid Colours
suitable for Dyeing Vegetable Tanned Leathers.[198]

[198] For explanation of Roman numerals see [end of Appendix D].

Yellows.
II.Napthol yellow S. (Ber.), (B.A.S.F.), (By.) and (C.).
VII.Quinoline yellow. (Ber.), (By.) and (B.A.S.F.).
II.Citronine. (Leon.)
IV.Solid yellow G. (Leon.)
IV.Solid yellow B. (Leon.)
V.Indian yellow S.
V.Azo-acid yellow.
IV.Indian yellow T. (C.)
VII.Indian yellow R. (By.) and (C.).
IV.Indian yellow G. (By.) and (C.).
IV.Cuba yellow. (C.), (W. Bros.) and (S.C.Ind.).
V.Azo-flavine RS. (B.A.S.F.) and (C.).
V.Azo-flavine 3R. (B.A.S.F.) and (C.).
VI.Circumein extra. (Ber.)
VII.Tartrazine. (B.A.S.F.)
Oranges.
V.Orange 2. (B.A.S.F.), (C.), (M.L.B.), (S.C. Ind.), (P.) (W. Bros.) and (By.).
V.Mandarin G extra. (Ber.)
V.Crocein orange. (K.) and (By.).
VI.Ponceaux 10RB, 4R, Bo, 4RB, 6RB. (Ber.), (By.) and (D.).
Bordeaux.
VII.Azo bordeaux. (By.)
IV.Bordeaux B extra. (By.)
VI.Bordeaux G. (By.)
V.Bordeaux Y. (W. Bros.)
V.Acid maroon. (M.L.B.) and (B.S. Spl.).
VIII.Chromatrop 6B. (M.L.B.)
Reds.
V.Fast red A. (Ber.), (By.), (B.A.S.F.), (B.S. Spl.) and (Leon.)
VIII.Fast red S. (M.L.B.)
VI.Fast red 21528. (By.)
Scarlets.
V.Crocein scarlet R. (By.) and (K.).
V.Crocein scarlet 2R. (By.)
VII.Fast scarlet B. (B.A.S.F.), (W. Bros.) and (K.)
Browns.
IV.Acid brown R. (C.)
V.Acid brown L. (B.A.S.F.)
V.Acid brown Y. (S.C. Ind.)
IV.Acid brown D. (C.), (B.A.S.F.)
IV.Acid brown (R.H. & S.)
IV.Acid brown 4601. (B.S. Spl.)
V.Acid brown D. (C.)
VII.Resorcin brown. (Ber.)
V.Acid brown. (Uer.)
IV.Acid brown R. (Ber.)
VIII.Acid brown Y. (M.L.B.).
VI.Solid brown o. (M.L.B.)
V.Fast brown. (By.)
V.Fast brown. G. (Ber.)
V.Fast brown. N. (B.A.S.F.)
IV.Fast brown. 3B. (Ber.)
V.Bronze acid brown. (By.)
VIII.Acid anthracine brown R. (By.)
V.New acid brown. (B.S. Spl.)
VI.Dark nut brown. (Uer.)
IV.New golden brown A1. (C.)
Blacks.
IV.Napthol blue black. (C.)
V.Napthylamine black 4B. (C.)
V.Napthylamine black 6B. (C.)
VII.Phenol black S. (By.)
IV.Phenylamine black 4B. (By.)
VII.Victoria black B. (By.)
Blues.
VIII.Fast blue R. (Ber.)
VIII.Bavarian blue DB. (Ber.)
V.Erioglaucine. (G.)
IV.Cyanole ext. (C.)
IV.Marine blue. (K.)
VII.Water blue N. (B.A.S.F.)
VIII.Water blue 4 B. (Ber.)
VII.Cotton blue II. (By.).
VII.Toluidine blue. (B.A.S.F.) and (By.).
VII.Water blue R. (Leon.)
VII.Water blue 3R. (Leon.)
VII.Water blue BTR. (B.A.S.F.)
Violets.
Acid violets (Lev.), (B.A.S.F.) and (By.)
IX.Acid violets 4R. (B.A.S.F.)
V.Acid violets R. (C.)
V.Acid violets R. (B.A.S.F.)
VI.Acid violets 3BA. (M.L.B.)
IV.Acid violets 3BN. (Lev.)
II.Acid violets 6B. (By.) and (C.).
III.Formyl violet S4B. (C.)
Greens.
IV.Acid green extra conc. (C.)
IV.Guinea green B and G. (Ber.)
IV.Acid green ext. (By.)
IV.Acid green GG ext. (By.)
IV.Acid green 225. (By.)
IV.Acid green BB. ext. (By.)
IV.Acid green o. (M.L.B.)
IV.Acid green 5677. (B.S. Spl.)
V.Capri green 2G. (Lev.)
Single Basic Dyessuitable for Dyeing Vegetable Tanned Leathers.
Browns.
IV.Vesuvine ooo ext. (B.A.S.F.)
II.Vesuvine B. (B.A.S.F.)
II.Vesuvine (C.)
III.Vesuvine conc. (M.L.B.)
III.Bismark brown ext. (Ber.) and (B.S. Spl.).
III.Bismark brown ext. M. (By.)
III.Bismark brown F. (By.)
IV.Bismark brown YS. (B.S. Spl.)
III.Bismark brown PS. (C.)
III.Bismark brown GG. (C.)
III.Bismark brown O. (L.)
III.Bismark brown G. (O.)
III.Bismark brown (S.C. Ind.)
III.Bismark brown NYY. (W. Bros.)
III.Bismark brown o. (M.L.B.)
II.Cannella. (B.S. Spl.)
II.Cannella. (B.A.S.F.)
II.Cannella. (C.)
V.Cannella. (S.C. Ind.)
II.Cannella S. (Ber.)
III.Cannella P. (W.)
IV.Nanking. (B.A.S.F.)
IV.Nanking. (R.H. & S.)
IV.Nanking. (S.C. Ind.)
III.Lavilliere’s 122. (By.)
II.Rheonine. (B.A.S.F.)
IV.Xanthine. (O.)
Yellowish Oranges.
III.Chrysoidines, (Leitch); R, (R.H. & S.)
IV.Chrysoidines ext. (W.).
II.Chrysoidines (S.C.Ind.); GG,(C.)
III.Chrysoidines G. (Leon.)
II.Chrysoidines RE. (Lev.)
III.Chrysoidines YY. (C.)
III.Chrysoidines cryst. (B.S. Spl.)
III.Chrysoidines G. (By.)
V.Chrysoidines cryst. (C.A.)
Yellows.
III.Auramine 2. (B.A.S.F.)
III.Auramine. (S.C. Ind.)
III.Auramine. (G.)
III.Auramine. (Ber.)
III.Auramine. (By.)
III.Auramine. (L.)
III.Auramine. (W.)
III.Auramine. (C.)
III.Auramine. (W.)
V.Auramine conc. (M.L.B.).
IV.Phosphine E. (B.A.S.F.)
IV.Phosphine L. (B.A.S.F.)
IV.Phosphine G. (Ber.)
IV.Phosphine. (O.)
IV.Phosphine. (C.)
IV.Phosphine Ext. (M.L.B.)
IV.Phosphine B ext. (S.C. Ind.)
III.Phosphine III., II., I. (Leon.)
III.Phosphine N. (Ber.).
V.Cori-phosphine. (By.)
V.Homo-phosphine. (Leon.)
V.Para-phosphine. (C.)
Greens.
III.Methyl green cryst. (By.) D.
V.Methylene green o. (M.L.B.)
II.Diamond green B and G. (B.A.S.F.)
II.Benzal green. (O.)
II.Brillt. green cryst. (M.L.B.)
II.Brillt. green cryst. (By.)
II.Brillt. green cryst. (O.)
II.Brillt. green cryst. (L.)
II.Brillt. green cryst. (Lev.)
II.Brillt. green cryst. (Uer.)
II.Brillt. green cryst. (S.C. Ind.)
II.Malachite green. (B.S. Spl.)
II.Malachite green. (Ber.)
II.Malachite green. (C.A.)
II.Malachite green. (K.)
II.Malachite green. (M.L.B.)
II.Malachite green. (Lev.)
II.Malachite green. (G.)
II.Malachite green. (O.)
Blues.
VII.Methylene blue B, 2B and R. (Ber.)
VII.Methylene blue. (B.A.S.F.)
VII.Methylene blue. (M.L.B.)
VII.Methylene blue. (Lev.)
VII.Methylene blue. (C.)
VII.Methylene blue. (C. & R.)
VIII.New methylene blue. GG. (C.)
VIII.New methylene blue. BB. (C.)
IV.New blue R. (Ber.)
V.New blue R. (By.)
VI.New patent blue 4B. (By.)
Violets.
IV.Methyl Violet 4B. (B.A.S.F.)
IV.Methyl Violet 4R. (K.)
IV.Methyl Violet 4R. (C.)
IV.Methyl Violet 3B. (By.)
IV.Methyl Violet 3B. (Ber.)
IV.Methyl Violet 2B. (M.L.B.)
IV.Methyl Violet (D.)
IV.Methyl Violet 6B. (Leon.)
IV.Neutral violet ext. (C.)
Bordeaux.
IV.Magenta WB. (Leon.)
IV.Magenta 3B. (Ber.)
IV.Magenta RE. (Leon.)
IV.Magenta WBG. (Leon.)
IV.Magenta. (M.L.B.)
IV.Magenta. (K.)
IV.Magenta. (B.A.S.F.)
IV.Magenta 4128. (B.S. Spl.)
Reds.
VIII.Rhodamine B extra. (Ber.)
VIII.Rhodamine B. (B.A.S.F.)
VIII.Rhodamine B. (By.)
VIII.Rhodamine (S.C. Ind.)
VIII.Rhodamine (M.L.B.)
VII.Safranine. (B.A.S.F.)
IV.Russian red G. (B.A.S.F.).
IV.Russian red B. (C.)
IV.Russian red (Ber.)
IV.Russian red (Uer.)
IV.Russian red B. (B.A.S.F.)
IV.Russian red G. (C.)
IV.Russian red (Ber.)
IV.Russian red R. (By.)
IV.Cardinal 4B. (By.)
VIII.Rhoduline red. (By.)
V.Safranine G ext. (C.)
VII.Safranine BS. (By.)
Safranine G ext. (Ber.)
Acid Mixtures suitable for Dyeing and Staining
Vegetable Tanned Leathers.
Basic Mixtures suitable for Dyeing and Staining
Vegetable Tanned Leathers.
Chrome Leather.

The following dye-stuffs are suitable for dyeing chrome leather. The leather after tanning, is boraxed in the usual manner and then mordanted by drumming or paddling in a tannin solution; for dark shades 3 per cent. gambier and 3 per cent. fustic extract (the weight being calculated on the leather struck out after boraxing) is suitable; for light shades 11⁄2 per cent. gambier is to be recommended. The leather, after mordanting, is fat-liquored and dyed, adding a weight of sodium or potassium bisulphate equal to that of the dye-stuff, to the dye-bath. The following is not by any means a complete list of the dyes which will dye chrome leather well, but merely representative.

After the goods are dyed, they should be well washed in tepid water to which has been added a little common salt; one pound to every three dozen skins being a suitable amount to use. When the goods have been washed, they are struck out by machine and are then ready for shaving, if the operation has not been performed previous to dyeing. The skins are afterwards nailed out flat, grain-side up, on boards, and a mixture of glycerine and water—3 lb. of glycerine dissolved in one gallon of water being a suitable strength—is well sponged on the grain-side; the goods are now lightly oiled (using a good sperm, neat’s-foot or mineral oil), before being taken to the drying room. When thoroughly dry they are taken off the boards, and placed with layers of damp sawdust between each skin, for a few hours in order to allow the goods to become suitably damp for staking. The skins should now be well staked by machine, the Haley (England), Slocomb or Vaughn (America) being good machines for this purpose ([p. 192]).

After staking, the goods are “soft-boarded,” and a thin coat of a weak linseed mucilage is applied to the skins, which are afterwards dried out and seasoned with the following mixture:—

“Soak 10 to 15 oz. of dry egg albumen for four hours in 1 gallon of cold water, with occasional stirring, strain off any insoluble matter and add 1 gallon of milk. A little carbolic acid (phenol) may be added to the above if it is desired to keep the finish for more than two or three days—1 oz. of phenol previously dissolved in a little water, added to each gallon of the finish, being a suitable amount.” A little dye should be added to the mixture.

After seasoning, the skins are dried out in the stove, glazed twice round and re-seasoned with the above mixture diluted with its own volume of water. The goods are dried out and again glazed, perched lightly, and finally boarded up from neck to tail in order to raise the popular straight-grain. Should the glaze be too bright the albumen solution may be reduced to half-strength.

When the goods have been glazed they are rubbed over on the grain side with a flannel cloth which is slightly damp with linseed oil, trimmed up, and are ready for sale.

Dyes Suitable for Dyeing Chrome-Tanned Leather.
Browns.
Yellowish Browns and Yellows.
Greens.
Violets and Blues.
Oranges.
Scarlets and Reds.

Most acid scarlets and reds dye chrome leather well on the mordant, particulars of which are given above.

Blacks.

These are dyed direct without any mordanting.

Titanium salts (potassium titanium oxalate and tanno-titanium oxalate) may be employed in conjunction with the coal-tar colours for dyeing chrome leather, with many advantages over the ordinary mordants, the colour produced being faster to light, rubbing, fuller in shade, and with much less tendency to “grinning.” When employing titanium mordants, the leather should be first lightly mordanted with some tannin solution and afterwards dyed with the titanium and dye-stuff in the same bath, in which case only “acid” dyestuffs may be employed. If desired the goods may be mordanted with the tannin mordant, afterwards treated with the titanium salts, washed and dyed; in this case the dyeing and application of the titanium mordant being carried out separately, the leather may be dyed with either the acid or basic dye stuffs. The titanium and tannin mordants may also be applied in the same bath.

Dyeing Chamois Leather.

The following colours dye chamois leather well, after washing the leather in a weak soda solution, mordanting with 3 per cent. basic chrome alum solution, and transferring to the dye-bath without washing. Equal weight of bisulphate of soda to that of the dyestuff is added to the dye-bath.

Basic Coal-Tar Colours.
Acid Coal-tar Colours.
Natural Dyestuffs.

A variety of shades may be obtained on chamois leather by mordanting in a 1 per cent. solution of the titanium salts above mentioned and then transferring without washing to the dye-liquor, which is best used in the drum. The colours which are most suitable are the Alizarin colours, Janus colours and the natural dyestuffs.

Alizarin Colours.
Alizarin blackproduceslight slate.
Alizarin orange„bright orange.
Alizarin blue„blue.
Azo-alizarin black„brownish maroon.
Azo-alizarin brown„reddish violet.
Alizarin red„bright scarlet red.
Azo-alizarin blue„slate blue.
Coerulein„yellowish green.
Azo-alizarin yellow„bright yellow.
Anthracene brown„fawn brown.
Acid anthracene brown G„brownish orange.
Acid anthracene brown R„dull chocolate brown.
Anthracene blue„pale blue.
Mordant yellow„lemon yellow.
Janus Colours.
Janus yellow G.producesbright orange.
Janus yellow R.„reddish orange.
Janus red„dark maroon.
Janus claret red„bluish maroon.
Janus brown R.„dark reddish chocolate.
Janus blue B.„bluish black.
Natural Dyestuffs.
Barwoodproducessalmon pink.
Logwood„dull reddish brown.
Fustic„bright yellow.
Turmeric„yellow.
Brazil wood„reddish brown.
Sapan wood„light nut brown.
Sumach„buff yellow.
Persian berries„light orange yellow.
Madder„red.
Quercitron bark„light orange yellow.
Cutch„fawn brown.
Campeche„canary yellow.
Peach wood„pale reddish tint.
Divi-Divi„buff yellow.

The leather is run in the dyestuff solution at a temperature of about 45° to 50° C. for about half an hour, and then lightly fat-liquored, if desired, and afterwards dried.

In addition to the dyestuffs mentioned above many basic colours may be employed after the treatment with titanium, some of these producing a colour lake with the titanium mordants.

As regards the permanency of the various colours to light, the reader is referred to an important paper by Mr. Lamb,[199] but in many cases the probable permanency is indicated by a number prefixed to the name of the colour in Roman figures, I. corresponding to the lowest, and X. to the highest permanency. In the research referred to, about 1500 samples of leathers dyed with coal-tar dyes were exposed to light for a series of “periods,” each equal in actinic power to nine days of the brightest summer sunshine. The most fugitive colours faded completely, even in the first “period,” and the most permanent before the end of the tenth. The prefixed numerals indicate to which of these “periods” the colour survived.

[199] Journal of Society of Chemical Industry, 1902, p. 156.