/- FRANKLIN INSTITUTE LIBRARY PHILADELPHIA Class€>!S>7*€> BookT"2>7S' Accession r4:iS 7^ Digitized by the Internet Archive in 2015 https://archive.org/details/pigmentspaintpaiOOterr '1 ,(iymU^* PIGMENTS, PAINT AND PAINTING PIGMENTS, PAINT AND PAINTING A PBACTICAL BOOK FOB PBACTICAL MEN BY GEORGE TMRY HonDon E. & F. N. SPON, 125 STEAND ^tia forfe 8P0N & CHAMBERLAIN, 12 CORTLANDT STREET 1893 rf c, a THE GETTY CENTER LIBRARY INTEODUCTION. In days gone by, the painter who served the usual term of apprenticeship was deemed to have done all that was required to qualify him for his trade. He may have learned little or much, but he had " served his time," and that was all that was expected of him. So far as it went, the training was good, because it was nothing if not practical, and practice is an essential element of skill. But nowadays such a training can only be considered partial ; mere practice, without any scientific knowledge of the principles which underlie it, is but half a qualification for the workman who aims at being really a master of his trade. When competition was unknown, and the low prices of raw material offered no inducement for passing off inferior or fraudulent substitutes, there was less need for a high degree of knowledge. But under modern conditions, the painter who is unable to gauge the qualities of the materials he uses, and who is ignorant of the rules which govern those qualities, and of the principles which determine the use of this and the rejection of that article, cannot long survive in the struggle for supremacy or even livelihood. Hence the need for a handbook such as this volume aims at being. Granted that our technical schools and colleges are affording a liberal and invaluable education to the work- vi PAINT, man who will avail himself of the opportunities given him, still a man does not remain for ever at school, and he needs a guide-book, handy of reference and accessible in price, to refresh his memory and supplement the information gained in the class-room and workshop. To fulfil this useful purpose is the aim and object of this unpretending volume. CONTENTS. CHAPTEE 1. PRELIMINARY. PAGE PAQB Colour .. .. .. 1 I Pigments .. .. .. 3 CHAPTEE II. BLACKS. General 5 Animal -black . . 6 Bone-black 6 Frankfort or Drop-black . 11 Ivory-black .. . 11 Lamp-black .. 11 Unimportant blacks — Aniline, candle, charcoal, coal, cork, German, iron, lead, manga- nese, Prussian, prussiate, Spanish, tannin . . . . 25 CHAPTEE III. BLUES. Cobalt blues — Coeruleum; Cobalt blue ; smalts Copper blues — Bremen blue ; Cseruleum ; Lime blue ; Mountain blue or Azurite ; Peligot blue ; Verditer Indigo .. Manganese blue 27 34 42 49 Prussian blue — General; Yellow prussiate ; Combina- tion of the cyanide and iron solutions; Antwerp blue; Bong's blue ; Brunswick blue ; Chinese blue ; Paris blue ; Saxon blue ; Soluble blue ; Turnbuirs blue Ultramarine 49 70 PAINT. CHAPTER IV. BROWNS. PAGE PAGE Asphalt or Bitumen . . 101 Mars brown . . 103 Bistre .. .. 101 Prussian brown .. 103 Bone brown . . .. 102 Rubens brown .. 104 Cappagh brown .. 102 Sepia .. .. 104 Cassel earth . . 102 Ulmin .. 105 Chicory brown 102 Umbers .. .. 105 Cologne earth . . .. 102 Vandyke brown .. 107 Manganese brown .. 103 CHAPTEE V. GREENS. Baryta . . 109 Mountain .. 131 Bremen 112 Paris .. .. 132 Brighton 112 Prussian .. 132 Brunswick .. 113 Rinmann .. 132 Chinese 118 Sap .. 132 Chrome .. 118 Scheele's .. 133 Cobalt .. .. 119 Schweinfurth .. .. 134 Douglas .. 120 Terre verte .. 134 Emerald .. 121 Titanium .. 135 Guignet's .. 125 Verdigris 135 Lokao .. .. 129 Verditer .. 136 Malachite .. 129 Verona earth . . 136 Manganese .. 130 Victoria .. 137 Mineral .. 130 Vienna 137 Mitis . . .. 130 Zinc .. 137 CHAPTER VI. REDS. Antimony vermilion . . .. 138 \ Chinese red .. ., 144 Baryta red .. .. .. 143 I Chrome orange .. 144 Cassius purple .. .. 143 I Chrome red .. .. 144 CONTENTS, Cobalt pink .. 144 Oxide reds .. 150 Cobalt red . , . * 144 Persian red . . 153 Colcothar 145 153 Derby red 145 Red lead 153 Indian red 147 Rouge .. .. 153 Lead orange . . .. 147 Venetian! red .. .. 153 Minium .. 148 Vermilion .. 153 Orange mineral .. 150 Victoria red . . .. 169 CHAPTER VII. WHITES. Baryta white . . 170 Magnesite .. 245 Blanc fixe 172 Mineral white .. 245 Charlton white 172 Orr's enamel white . . .. 245 China clay 172 Paris white .. 246 Enamelled white 183 Permanent white 246 English white 183 Satin white 246 Gypsum 183 Spanish white .. 246 Kaolin .. 183 Strontia white .. 246 Lead whites or White leads 183 Terra alba .. 246 Lime white 245 Whiting .. 246 Lithophone 245 Zinc whites .. .. 247 CHAPTEK VIII. YELLOWS. Arsenic yellow . . . . 257 Aureolin yellow . . . . 257 Cadmium yellow .. .. 258 Chrome yellows . . . . 258 Gamboge .. .. 270 King's yellow .. .. 271 Naples yellows . . . . 271 Ochres 272 Orpiment 280 Realgar 280 * Siennas .. .. .. 281 X PAINT. Brazil-wood lake Carminated lake Carmine CHAPTEE IX. LAKES. PAGE 283 283 283 Cochineal lake Madder lake . . Yellow lakes . . PAGK 284 284 285 CHAPTEE X. LUMINOUS PAINTS 286 CHAPTEE XI. EXAMINATION OF PIGMENTS. Fineness Body or covering power 293 j Colour .. 293 I Durability 293 294 CHAPTEE XII. VEHICLES AND DRYERS. Generalities . . .. 295 Dryers.. 316 Ground-nut oil .. 297 Litharge 316 Hcmpseed oil .. 298 Cobalt and manganese benzo- Kukui or Candle-nut oil .. 298 ates .. 318 Linseed oil .. 299 Cobalt and manganese borates 318 Menhaden oil . . .. 303 Resinates 318 Poppy-seed oils .. 305 Zumatic dryers 318 Tobacco-seed oil .. 306 Manganese oxide 318 Walnut oil 307 Guynemer's dryer 319 Wood or Tung oil .. 308 Manganese oxalate . . 319 Extraction of seed oils .. 308 Boiled oil 320 CONTENTS. xi CHAPTER XIII. PAINT MACHINERY. PAGE FACE Wright & Go's 339 I Brinjes & Goodwin's 346- Hind and Lund's , , . . 345 I CHAPTER XIV, PAINTING. The surface , . 351 Discoloration .. 356 Priming 352 Composition „. 358 Drying .. 353 Area covered . . 360 Filling .. 354 Measuring 360 Coats .. 355 Carriage and Car painting . 361 Brushes .. 355 Woodwork painting . . 368 Water-colours . . .. 356 Iron painting . . 369 Removing odour .. 356 Fresco painting 378 INDEX 383 % ILLUSTRATIONS. FIGURE PAGE 1, 2. Bone-black Furnace .. .. .. .. 8 3-lL Apparatus for Making Lamp-black 12-22 12. Furnace for Boasting Cobalt Ores 31 13. Furnace for Making Smalts 33 14-17. Yellow Prussiate Furnace .. .. ., 60 18-20. Hannay's White Lead Furnace 217 21-25. Lewis's White Lead Furnace 226, 230 26, 27. MacIvor's White Lead Process 233, 239 28. Apparatus for Making Zinc Oxide .. .. 248 29. Apparatus for Making Zinc Sulphide .. .. 253 30-32. Furnace for Boasting Ochres .. .. .. 278 33-39. Apparatus for Extracting Seed-Oils .: 309-315 40-44. Wright & Co.'s Paint Mills .. .. 340-344 45. Hind & Lund's Paint Mill 346 46-48. Brinjes AND Goodwin's Paint Mills .. 347,348 49. Noakes & Co.'s Metallic Keg 350 PAINT. CHAPTEE 1. PRELIMINARY. Colour. — The term " colour " is inappropriately given by common usage to material substances which convey a sense of colour to the human eye, but is properly restricted to that sense itself. The material colour should be called "pigment" or "dyestuff" in the raw state, and paint when compounded with other substances for application in the form of a coating. The sense of colour is due to light. In the absence of light there is no colour, only blackness; and black is really no colour, but an absence of colour. Very many conditions combine to cause different colour sensations, some of which are understood, while others we are not able to explain. For instance, take the action of heat upon a solution of chloride of cobalt. As soon as the liquid becomes warm, the pink colour disappears and gives place to blue; but on pouring water into it, the blue vanishes and the pink re- appears. Again, on heating the blue crystals of sulphate of copper they become white, but the blue colour comes back when water is added, and the solution assumes a deeper tint as it dissolves more of the white powder. If all the rays are cut off from an electric light except those which are in and beyond the violet, and a flask con- B 2 PAINT. taining a solution of sulphate of quinine is held in that portion of the spectrum, it will become luminous. The same thing will occur even more strikingly on placing a piece of uranium glass in the ultra-violet rays. The ex- planation of this phenomenon is that beyond those rays which give light there are others which do not give light, i. e. which do not cause us to experience the sensation of light ; the reason being that their vibrations are too rapid. But when certain other substances, such as sulphate of quinine, or a thin slip of uranium glass, are placed in the path of the rays, this rapid motion is arrested and modified, and these rays, which in themselves are not luminous, are reflected back to our eyes as luminous rays. The rapidity of the vibrations being moderated, our retinas become sensible to them as rays of blue light. Colour does not depend only upon chemical composition nor solely upon the aggregation of the particles, but upon these and other things besides not yet explained. All matter is in a state of motion. If you heat a substance you communicate an increased activity of motion to the particles of which it consists. When certain coloured rays of light are falling upon a substance, these coloured rays of light have a motion peculiar to themselves. It may be that the degree of motion in that substance, either existing in it naturally without heating, or communicated to it by artificial heating, is such that these rays of light are precisely those which that substance is not capable of sending back to our eyes. They are then absorbed or destroyed in some way, by the particular state of that substance upon which they fall ; and those rays which the substance is capable of reflecting back are mainly sent back to our eyes. Certain colours, such as blue, yellow, and green, absorb certain rays more or less perfectly, and reflect back in the main blue, yellow, and green to our eyes. Hence it is incumbent on those who are studying colour, and who are interested in the purity and permanency of colour, to comprehend at least PRELIMINARY, 3 the principles of that science of liglit which tells of the action of light upon various bodies that are used as pigments in painting. If we put together two substances one of which destroys or modifies the chemical condition or state of the other, then certainly one of those substances, and very probably both, will lose the colour which it had before it came into contact with the other. It is therefore most important that all engaged in the preparation and use of colours should make a study of this science of light. Of almost equal value is a study of the science of heat. We have seen what beat can do in changing the conditions of a substance. To give another instance. The black sulphide of mercury, after sublimation by heat, exhibits properties, imparted to it by the heat, which it did not possess before, i. e. it can, by trituration, be brought to display a red colour. On showing the spectrum on a screen, if some solution of soda or other sodium salt be held in the course uf the light, almost all the coloured rays but one will be cut off, and a little band is seen in the yellow part of the spectrum. This is because the sodium flame is almost " monochromatic," or single-lined: it cuts off all the colours but the yellow. Again, if metallic thallium is held in the fl ime, the only band remaining in the spectrum will be the green ; and if a lithium salt, the only surviving colour will be rrd. Pigments.— The term " pigments " is applied to those colouring matters which are mixed in a pov*^der\ form with oil or other vehicle for the purpose of painting. They differ in this respect from the dyestuffs, which are always employed in solution. A very large proportion of the pig- ments in common use are derived from the mineral kingdom, the most notable exceptions being found in ihe blacks and lakes. All pigments are required to possess "body," or density an 1 opacity ; to be insoluble in water and most other solvents, except the stronger mineral acids ; and to be inert, or incapable of exercising chemical or other influence B 2 4 PAINT, on each other or on the vehicle or drier with which they are mixed prior to use. They may be conveniently classified according to their colours in the first place, reserving the consideration of their preparation for use for a later chapter. The chief classes are Blacks, Blues, Browns, Greens, Eeds, Whites, and Yellows. CHAPTER II. BLACKS. All the black pigments in use owe their colour to carbon, and all are produced by artificial means, no natural form of carbon possessing the requisite qualities. Several manufactured carbonaceous substances are known in commerce under the generic name of " Blacks." The most important of these are animal-black, bone-black, Frank- fort-black, ivory-black, and lamp-black. They are usually obtained by carbonising organic matter, particularly bones, in closed vessels or crucibles, or by collecting the soot formed by the combustion of oily, resinous, and bituminous substances. Other blacks than those enumerated are manufactured, but only on so small a scale as to be of no commercial importance. Carbon, lamp, and vegetable blacks consist almost entirely of carbon, containing usually from 98 to 99 J per cent, of that substance, the residue consisting of a little ash, water, and occasionally unburnt oil. Bone and ivory blacks, on the other hand, are chiefly composed of mineral matter, which may amount to 65 or 75 per cent, and is mainly represented by phosphate of lime. Their actual colouring matter, the carbon, only constitutes 15 to 30 per cent, of the mass. The balance is water and unburnt animal tissue. Blacks prepared from animal matters other than bone and ivory carry 40 to 80 per cent, of carbon, and their mineral matter is generally in the form of carbonates of lime and of the alkalies. The principal impurity to be watchful of in the vegetable and lamp blacks is a small quantity of oily matter which 6 PAINT. may seriously interfere with their drying qualities. They should leave very little ash after being burned in a crucible. Bone and ivory blacks are sometimes vabied as much for their mineral matter as for their colouring matter. The pro- portion of this mineral matter is ascertained by heating a certain weight of the black to red heat in a crucible till every trace of black has disappeared, and then weighing the residue. The residue should next be boiled in strong hydro- chloric acid till it is dissolved ; if there is any which will not dissolve it is most probably barytes, which has been added as an adulterant and to make the black weigh heavy. When the solution is complete, the addition of ammonia will throw down a precipitate of phosphate of lime, which should equal 60 to 70 per cent, of the original weight of mineral matter. If much less than this, it is likely that whiting or gypsum has been mixed with the pigment. As carbon is not acted upon by acids or alkalies, it follows that all pure carbon blacks are in themselves perfectly stable and perma- nent pigments, and that they exert no influence on other pigments with which they may be mixed. Animal-black. — This substance is almost identical with bone-black, but is generally in a more finely divided state. Any animal refuse matter may be used in its preparation, such as albumen, gelatine, horn shavings, &c. These are subjected to dry distillation in an earthenware retort. An inflammable gas is given off", together with much oily matter, ammonia, and water, while a black carbonaceous mass is left behind. This is washed with water and powdered in a mill, the product being animal-black. It is largely used in the manufacture of paint, printing ink, and blacking. Bone-black. — When bones are heated in a retort or crucible, the organic constituents are decomposed and carbonised. A mixture of combustible gases is given off; some of these do not condense on cooling, others condense in the form of a heavy oil, called bone-oil. Also much water con- taining tarry water and ammoniacal salts in solution passes BLACKS, 7 over. The residue in the retort or crucible consists of finely divided carbon, in intimate mixture with the inorganic con- stituents of the bones : this mixture constitutes ordinary bone-black, or animal charcoal, as it is sometimes called. The inorganic portion may, if required, be removed by washing the residue in dilute hydrochloric acid. The process, as worked on the large scale, is carried on in different ways, according as it is desired to collect the volatile condensable portion of the distillate, or to allow it to escape. In the latter case, when it is required to obtain only bone-black, the apparatus employed is of a very simple nature, and the amount of fuel needed is comparatively small. The carbonisation is effected in fire-clay crucibles, 16 in. high and 12 in. diameter. These are to be preferred to crucibles made of iron, which were much used at one time, since they do not lose their round form when subjected to a high temperature ; in consequence of this, they fit more closely together in the furnace, less air can penetrate, and therefore less of the charcoal is consumed by oxidation. The furnace is an ordinary flat hearth, having a superficial area of about 40 square yards, and is covered in with a flat arch, all of brickwork. The fireplace is situate in the middle of the hearth ; the crucibles are introduced through doors in the front, which are bricked up when the furnace is filled ; each furnace holds eighteen crucibles. I'he crucibles, filled with the coarsely broken bones, are covered with a lid luted on with clay- To economise fuel, the furnaces should be in a row, and placed back to back. The arrangement of the furnace and pots is shown in Figs. 1 and 2. A is the fireplace ; B, the crucibles, eighteen in number, spread over the floor of the furnace in a single layer ; c, cZ, e, and / are the flues for conducting away the heated gases arising from the calcination of the bones, as well as the waste heat itself ; the last portion of the flue is fitted with a damper The furnaces are intended to be built in fours, back to back, the waste heat serving in a great measure to 8 PAINT, conduct the operation of the revivifying apparatus placed in the centre of the group, and marked 0. When the furnace is filled and the doors are bricked up, the heat is slowly raised to redness, at which point it is kept for six or eight hours. The combustible gases are evolved and consumed in the furnace as the bones begin to decompose, and by this means so much heat is produced that only a BLACKS, 9 small quantity of fuel is needed to maintain the required temperature. When the carbonisation is complete, the doors are taken down and the crucibles are removed to cool, their places being immediately filled with fresh ones. The heat must be kept as uniform as possible throughout the process : if it be not sufficiently high, the bone-black will contain a portion of undecomposed organic matter, which renders it quite unfit for use ; if, on the other hand, the temperature be raised too high, the bone-black will become dense and compact, whereby its efficacy as a decoloriser is much reduced. When the charcoal in the crucible has become perfectly cool, it is removed and crushed. When required for decolorising or deodorising purposes, it is only roughly broken up into small lumps, in which form it is most readily applicable. The crushing is effected by means of two grooved cylinders, consisting of toothed discs, alternately 10 and 12 in. in diameter. These are so placed that the 10-in. discs of one cylinder are opposite the 12-in. discs of the other, and thus, in revolving, the carbonised bones are crushed to fragments between them, but are not reduced to powder. They are passed successively through six of these mills, the cylinders of each couple being nearer to each other than the last. Finally the crushed bones are carefully sieved ; the powder is placed apart from the lumps, again passed through finer sieves, and sorted out into different sizes. A furnace such as that described above will carbonise four charges of bones in one day, each charge being more than half a ton in weight. With careful work, the bones will yield 60 per cent, of bone-black, or more than one ton daily. If it be required to condense the volatile gaseous products of the carbonisation, this process is conducted in retorts similar to those used in the manufacture of acetic acid from wood : these are so arranged that the whole of the gaseoi^s products are condensed and collected. The aqueous portion of the distillate is usually evaporated down to obtain salts of lo PAINT. ammonia ; the uncondensable gases may be employed for illuminating purposes. The manufacture of bone-black is usually carried on in the neighbourhood of large towns, where a good supply of bones may be readily obtained. Ordinary bone-black has about the following composition : Phosphate and carbonate of lime, and sulphide or oxide of iron, 88 parts ; charcoal, containing a small quantity of nitrogenous matter, 10 parts ; silicated carbide of iron, 2 parts. The decolorising properties of bone-black are due solely to the presence of the charcoal. When intended for use as a deodoriser or decoloriser, bone- black should be kept carefully excluded from the air, for by exposure it loses this power to a great extent, and becomes almost inert. That which has been freshly burned is there- fore best for these purposes. The cost of production of bone-black may be calculated as follows : — £ s. d. Eent and taxes . . . . 0 8 0 Interest, repairs, and wear and tear . . . . 0 7 2 Contingencies and trans- ports 0 2 4 £ s. d. 4 tons fat bones at 4s. percwt 16 0 0 27i bushels coals .. .. 13 9 2 firemen 0 4 9 4 workmen 0 8 0 1 carman 0 2 4 2 horses 0 5 7 Breaking up the bones . . 15 4 Produce : — Black, 60 per cent., say 38 cwt. in grains, at 148. 13 10 9 10 cwt. fine, at 55. 6