The art of dyeing and staining marble, artificial stone, bone, horn, ivory and wood, and of imitating all sorts of wood : a practical handbook for the use of joiners, turners, manufactures of fancy goods, stick and umbrella makers, comb makers, etc.

Front matter

THE ART OF

DYEING AND STAINING

MARBLE, ARTIFICIAL STONE,

Preface

In recent times the dyeing and staining of wood, bone, horn and ivory, like so many other crafts, has been completely revolutionised, and has experienced a com¬ plete series of improvements. The introduction of the coal-tar colours has put at the disposal of the industry a number of dyes and stains which are now used in enormous quantities. Many dyers and stainers long remained ignorant of the very existence of these artificial dye stuffs.

In spite of the compulsory limitation of space, this manual gives an exhaustive account of the modern practice of dyeing and staining wood, bone, ivory and marble. All new processes have been tested, and have been inserted only when they have been found to be of practical utility. In this way much space has been saved for really important matter.

I have adhered strictly to my intention of giving only reliable recipes, and that in such a form that any practical worker can make use of them without further trouble. I hope, therefore, that this little work will be found of real service to the industry.

THE AUTHOR.

Digitized by the Internet Archive in 2018 with funding from Getty Research Institute

Table Of Contents

Preface . page iii

Introduction . ,, vii

Acids : Sulphuric, 1 ; Hydrochloric, 4 ; Nitric, 4 ; Sulphurous, 5 ; Oxalic, 6. Alkalies : Caustic Soda, 6 ; Carbonate of Soda, 8 ; Borax, 9 ; Waterglass, 9 ; Ammonia, 9.

Introduction

The dyeing or staining of wood, ivory, bone and marble essentially consists in giving them a different colour from their natural one. It goes without saying that the process adopted must depend on the nature of the material. As a general rale, the deeper the stain penetrates the more durable the resulting colour will be. Most of the dyes used are gradually bleached by exposure to light and air, so that it becomes necessary to protect them from air, light and damp by a coating of varnish.

While in the textile colouring industries we draw a distinction between dyeing (Farben) and mordanting (Beizen), and always regard the latter operation as preliminary to the former and as making the material fit to take up the dye, we do not recognise any such distinction in the branch of dyeing dealt with in this book. I should like to say that the words “ Farben ” and “Beizen” are here looked upon as synonymous, to prevent all risk of misapprehension.

The directions given for the production of the different colours on the materials treated of are fully given in vm

INTBODUCTION.

the body of the book. It has, however, been necessary to condense everything as much as possible. It need only be mentioned here that the operator will not get good results, even with the use of the best recipe, unless he understands the substances he is working with and the way in which they behave one to another.

I. Acids

Sulphuric Acid.

Of all the acids which are used for our purposes sulphuric acid certainly takes the chief place. It is partly used with other stains to give them particular shades or for the solution of indigo.

As a rule, two sorts of this acid are known, the differ¬ ence being in the method of manufacture.

The so-called English sulphuric acid is made by burning sulphur or iron pyrites in ovens with a good draught. The sulphurous acid produced passes, by a somewhat high chimney, into the so-called lead chambers. These are rectangular rooms of lead, supported by wooden framing, and arranged in series SO' that the gas passes through them in turn. An uninterrupted supply of air, which is neces¬ sary for the success of the operations, is introduced through a pipe leading from the last chamber to the grate of the ovens. In the first chamber the mechanical impurities of the sulphurous acid settle to the floor, and the purified gas passes into the second chamber, which contains vessels filled with nitric acid. This is reduced by the sulphurous acid, forming oxides of nitrogen, and then nitrous acid, which becomes intimately mixed with the sulphurous acid. The mixture passes into the third

MORDANTS AND STAINS.

chamber, into which steam is blown. This, mixing with the two gases, converts the sulphurous into sulphuric acid, by means of oxygen from the nitrous acid. The dilute sulphuric acid falls in drops on to the floor of the chamber. A fourth smaller chamber is requisite to com¬ plete this precipitation of the sulphuric acid, and into it also steam is blown. Oxides of nitrogen escape thence into the outer air. The sulphuric acid thus obtained is, however, very much diluted, and must be concentrated first in lead and then in platinum vessels. English sul¬ phuric acid generally has a density of 66 deg. B.

The preparation of the so-called Nordhausen sulphuric acid is quite different. Here sulphate of iron, consisting, as is well known, of ferrous oxide, sulphuric acid and water, is first calcined in special ovens to get rid of the larger part of its 40 per cent, of water, and then heated more strongly in ranges of long-necked fireclay retorts over an open fire. As soon as white fumes (anhydrous sulphuric acid) issue from the necks of the retorts, the condensers are luted on, and the fire is raised till the retorts are red-hot, and they are kept so till fhe con¬ densers, which heat up at first, begin to get cool again. This is a sign that all the sulphuric acid has been dis¬ tilled over, and that the process is therefore at an end. The yield is about 45 per cent, of sulphuric acid, which is at once stored in earthenware bottles. The residue in the retorts consists principallv of sesquioxide of iron, a substance which, when ground and levigated, is known as rouge or colcothar. This process used to be confined almost exclusively to Nordhausen whence the acid was sent in all directions.

These two sorts, quite differently manufactured, of sul¬ phuric acid, although agreeing in their general properties, yet differ in many resjmcts. Nordhausen acid emits thick white fumes when a vessel of it is opened, and English sul-

ACIDS.

phuric acid does not. The reason is to be found in the peculiar constitution of the Nordhausen acid. While the English acid consists of equal parts of anhydrous acid and water, so that it is a hydrate of the former, the acid from Saxony consists of a compound of this hydrate with the anhydrous acid. It is the escape of the anhydrous acid that causes the fumes above spoken of, when it com¬ bines v/ith the water vapour of the atmosphere. It can thus be readily seen how injurious it is to the Nordhausen acid to leave the vessel containing it open. Indigo dis¬ solves much better in the Nordhausen than in the English acid. Nordhausen sulphuric acid is thick like oil, so that it deserves the name of oil of vitriol better than the English acid, which is somewhat thinner. Both acids are remarkable for their extraordinary affinity for water. They not only absorb enough water vapour from the air to become considerably diluted, but when added to water combine with it with much evolution of heat. Two practical warnings can be deduced from these cir¬ cumstances. One is to keep bottles of sulphuric acid carefully stoppered ; the other is never to pour water on to the acid. If this is done, so much steam will be gener¬ ated that the acid will be thrown violently about. It is essential always to pour the acid into water, and that slowly and with constant stirring, especially if the water is hot.

Nordhausen oil of vitriol freezes at 18 deg. C., the Eng¬ lish acid at 34 deg. C. Both kinds of acid can be bought quite pure enough for our purposes. It is only necessary to see that the density is as high as it professes to be. This can always be easily ascertained by means of a hydro¬ meter.

MOBDANTS AND STAINS.

Hydrochloric Acid.

This substance is artificially prepared by distilling common salt with sulphuric acid. To get anhydrous hydrochloric acid the vitriol must be used concentrated, but it is used diluted when it is intended to make dilute hydrochloric acid. In a state of purity hydrochloric acid is colourless. It may be made yellow by dirt having fallen into it, or by the presence of a trace of free chlorine. The white fumes which it forms in the air are formed by the hydrochloric acid gas which escapes from it condens¬ ing with atmospheric water vapour. Concentrated hydro¬ chloric acid has a destructive action both on vegetable and on animal substances. Its commonest impurities are sulphuric acid and sulphate of soda, which have been mechanically carried over by a too rapid distillation. Chloride of iron, too, may be carried over if the salt used contains iron. Free chlorine as an impurity in hydro¬ chloric acid means that the oil of vitriol used in its manu¬ facture contained nitric acid, which sets free the chlorine from some of the hydrochloric acid.

Aqua-regia is made by mixing hydrochloric acid with twice its weight of nitric acid. It contains free chlorine, by means of which it exerts most of its effects.

Hydrochloric acid is often used for bleaching various materials, and is much employed in producing brilliant shades in wood-dyeing.

Nitric Acid.

For our purposes, the use of nitric acid is somewhat restricted. It is used mixed with other stains, or alone for the production of yellows.

It is a colourless liquid, with a characteristic acid smell and taste. When concentrated it emits into the air slight

ACIDS.

white fumes, which are caused by the vapour of the acid combining with moisture from the air. It absorbs mois¬ ture from the atmosphere. The commercial reddish-brown aqua-fortis is the strongest nitric acid mixed with nitrous acid. From what has been said about nitric acid, it follows that it too must be kept in carefully closed vessels.

Sulphurous Acid.

This acid is of no interest to us, except as a bleaching agent.

Sulphurous acid is formed by direct combination when sulphur is burnt in air o-r in pure oxygen, and also by roasting many metallic sulphides, such as pyrites. It can be obtained chemically pure together with sulphate of copper by heating copper with concentrated sulphuric acid. Another way is to mix 24 lb. of anhydrous ferrous sulphate with 10 lb. of sulphur, and to heat the mixture in a retort provided with a wide delivery tube. The residue in the retort is sulphide of iron, which can be used for making sulphuretted hydrogen. Sulphurous acid is a colourless gas of sp. gr. 2.27, and smells like burning sul¬ phur. Its inhalation causes coughing and a feeling of suffocation. It neither burns nor supports combustion, and burning substances are at once extinguished by it. At from 15 to 20 deg. C. and under a pressure of three atmospheres it liquefies to a mobile fluid of sp. gr. 1.49, which produces great cold on evaporating. It is fairly soluble in water, which absorbs eighty times its own volume of the gas at 0 deg. C., and fifty times at 10 deg. C. The solution is colourless and acid, with a suffocating smell like that of the gas. It has an unpleasant taste, and is rather unstable. The gas bleaches many dyes in the presence of water, without, however, actually destroy¬ ing the colouring matter as chlorine does.

MORDANTS AND STAINS.

Oxalic Acid.

This acid occurs ill commerce in finely formed four¬ sided white plates, and is used a good deal for our pur¬ poses. It is used for grading many colours, and materially assists sulphurous acid in bleaching.

Other acids, such as tartaric and -citric, are not used in our business. The two just mentioned are dearer than oxalic acicl, and give no better results than that acid, which is cheap and effective.

II. Alkalies

Caustic Soda.

Caustic soda, or sodium hydrate, is put on the market jin drums or in solutions of various strengths. It is pre¬ pared by the action of lime on a solution of carbonate of soda, when the carbonic acid is transferred to the lime. The caustic soda lye is drawn off, evaporated to- the proper concentration, and then filled into’ iron drums in which it sets to a solid mass. The following table of caustic soda lyes (after Lunge) will be found useful : —

Specific Gravity.

Degrees Baume.

Percentage of NaHO by volume.

Grammes NaHO per litre.

1.007

.61

1.014

1.2

1.022

1.029

2.71

1.036

3.25

1.045

1.052

4.64

1.06

5.29

1.067

5.87

1.075

6.55

1.083

7.31

1.091

1.1

8.68

1.108

9.42

1.116

10.06

ALKALIES.

Specific Gravity.

Degrees Ban me.

Percentage of NallO by volume.

Grammes NaHO per litre.

1.125

10.97

1.134

11.84

1.142

12.64

1.152

13.55

1.162

14.37

1.171

15.13

1.18

15.91

1.19

16.77

1.2

17.67

1.21

18.58

1.22

19.58

1.231

20.59

1.241

21.42

1.252

22.64

1.263

23.67

1.274

24.81

1.285

25.8

1.297

26.83

1.308

27.8

1.32

28.83

1.332

29.93

1.345

31.22

1.357

32.47

1.37

33.69

1 1.383

34.96

36.25

1.41

37.47

1.424

38.8

1.438

39.99

1.453

41.41

1.468

42.83

1.483

44.38

! 1.498

46.15

1.514

47.6

! 1.53

49.02

The solution of caustic soda when packed in a drum is always attended with difficulty and risk, unless an ap¬ paratus is at hand for dissolving the caustic soda in the drum by means of a current of steam. This is done by placing the drum over a pan intended to' catch the lye flowing from it. A suitably placed pipe leads the steam from below into an opening made at the proper spot, and the melting process begins of itself.

MORDANTS AND STAINS.

Carbonate of Soda.

Carbonate of soda, or sodium carbonate, formerly made by burning certain sea-weeds, is now an artificial product only. Its manufacture may be divided into the old, or Leblanc process (now almost obsolete), and the Solvay process, which is now practised in all civilised countries. It consists in saturating with carbonic acid a brine pre¬ viously treated with ammonia gas, whereupon carbonate of soda is precipitated. The precipitate is ignited, and the resulting mono-carbonate is sold as calcined soda,. .

Anhydrous calcined soda contains 58.58 per cent, of soda, and 41.42 per cent, of carbonic acid; while the crystallised salt contains 21.81 per cent, of soda, 15.43 per cent, of carbonic acid, and 62.76 per cent, of water.

The following is a table of carbonate of soda solutions after Lunge : —

Specific Gravity.

Degrees BaumA

Weight per Cent, of Na2C03.

Grammes Na2C03 per litre.

1.007

.67

6.8

1.004

1.33

13.5

1.022

2.09

21.4

1.029

2.76

28.4

1.036

3.43

35.5

1.045

4.29

44.8

1.052

4.94

1.06

5.71

60.5

1.067

6.37

1.075

7.12

76.5

1.083

7.88

85.3

1.091

8.62

1.1

9.43

103.7

1.108

10.19

112.9

1.116

10.95

122.2

1.125

11.81

132.9

1.134

12.61

1.142

13.16

150.3

1.152

14.24

164.1

ALKALIES.

Borax.

Sodium borate or borax is a compound of soda and boric acid. It lias only feebly alkaline properties, but lias nevertheless much dissolving and purifying action. Unfortunately it is dear, so that its use is not universal.

Waterglass.

Waterglass or silicate of soda is obtained by fusing to¬ gether 100 lb. of finely powdered quartz, 60 lb. of calcined Glauber’s salt and from 15 to 20 lb. of coal. It comes on the market mostly in the form of a syrup, and contains about 65 per cent, of wafer and 27 per cent, of silica.

Ammonia.

Liquid ammonia is a solution of ammonia gas in water, which can absorb half its own weight of the gas, thereby acquiring its characteristic smell, taste and properties. As the water increases largely in volume by absorbing the gas, the specific gravity of the solution is less than that of water. In fact, the specific gravity of solutions of ammonia is the best test of their value. All adultera¬ tions and impurities increase the specific gravity. Am¬ monia can be obtained in all sorts of different ways, for example from putrid urine, from nitrogenous animal offal such as horns, hoofs, hair, etc., but at present it is prepared solely from the so-called ammonia-liquor from gas-works.

The following table shows the percentage of ammonia in solutions of different specific gravities : —

Specific Gravity.

Percentage of NH3

Specific Gravity.

Percentage of NH-

.8844

.8877

34.4

.8848

35.8

.8881

34.2

.8852

35.6

.8885

.8850

35.4

.8889

33.8

.886

35.2

.8894

33.6

.8864

.8898

33.4

.8868

34.8

.8903

33.2

.8872

34.6

.8907

.8911

32.8

.9021

28.2

.8916

32.6

.9026

.892

32.4

.9031

27.8

.8925

32.2

.9036

27.6

.8929

.9041

27.4

.8934

31.8

.9047

27.2

.8938

31.6

.9052

.8943

31.4

.9057

26.8

.8948

31.2

.9063

26.6

.8953

.9068

26.4

.8957

30.8

.9073

26.2

.8962

30.6

.9078

.8967

30.4

.9083

.8971

30.2

.9089

25.6

.8976

.9094

25.4

.8981

29.8

.91

25.2

.8986

29.6

.9106

.8991

29.4 .

.9111

24.8

.8996

29.2

.9116

24.6

.9001

.9122

24.4

.9006

28.8

.9126

24.2

.9011

28.6

.9133

.9016

28.4

.9139

23.8

.9145

23.6

.9245

20.2

.915

23.4

.9251

.9156

23.2

.9257

19.8

.9162

.9264

19.6

.9168

22.8

.9271

19.4

.9174

22.6

.9277

19.2

.918

22.4

.9283

.9185

22.2

.9289

18.8

.9191

.9296

18.6

.9197

21.8

.9302

18.4

.9203

21.6

.9308

18.2

.9209

21.4

.9314

.9215

21.2

.9321

17.8

.9221

.9327

17.6

.9227

20.8

.9333

17.4

.9233

20.6

.934

17.2

.9239

20.4

.9347

METALLIC SALTS.