A Treatise on Calico Printing, VOL. I-II
Printed for C. O'Brien, Bookseller, Islington, and fold by Bew, Paternoster-row: Richardson, Royal Exchange: Murray, Fleet-Street: And the Booksellers of Manchester, Glasgow, Dublin, &c.
1792
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(31) The acid of the allum is the vehicle for carrying the earth into the pores of the cloth: this substance, from being moistened, shews a disposition to unite with the principle of inflammability, on which colours depend.
The principle of attraction consists in 1. The astringent and the colouring substance) must be mutual in their powers of attraction. 2. They must be at a distance proportioned to their powers of attraction. 3. This force must be superior to that with which either is attracted by the fluid it is in.
(32) Acids having greater affinity with alkali than with earth, they leave the earth in form of a precipitate. See Rule 2, of the principles of combinations.
(33) It is a knowledge of this nature that callico-printers are requested to acquire, in order to ascertain the quantity of madder, weld, &c. necessary to be used as mentioned in maddering. — See the article Maddering.
As lakes are caused by the combination of one substance with another, upon a principle similar to what is above alluded, it will be here just observed as an example, that if a decoction of turmeric or madder, be made in a watery solution of fixed alkali and a proper quantity of solution of allum be added, the yellow or red particles will subside, but at the same time the acid of the allum being absorbed by the alkaline salts, the earth of the allum likewise subsides and dilutes and likewise brightens the colour, the cause of this operation is however allowed to be not fully known.
(34) In callico-printing this seems to be the case, from the danger purple and sometimes the reds are generally in, when in the weld copper, but this is most; likely to be the case when tartar or saccharum is used, they being (as observed before) only alte rants. It may however here be said, that the same salts being again used, may in some degree job With those that were used before, separating them, as it were, from the other substance to which they are joined; or it may be said (see below) that the yellow particles find admission into pores, not filled by the red or purple, when opened by the hot water.
Their solubility, as well as that of the allum before, formed into a cement by uniting with madder, &c. is oftentimes too evident when one colour is laid over another, even when stowed as much as possible, (in Printers' phraseology the colour is said to run) and this is particularly evident in heavy ground-work, and most so in black grounds, with large masses of purple.
Theorists do not seem clear in the case of several colours, raised at once, or in succession; as where purple is laid over red, blue over yellow, yellow over purple, or over purple and red, and so on; as here it can only seem that the salt first conveyed does not enter all the pores, but that' it contracts some, and leaves others open, which in turn are entered by succeeding applications; some have thought that every pore would admit any number of colouring particles, one above another, and that as they succeeded each other, like blue over yellow making a green, different shades were accordingly formed.
(35) In Percival's Essays it is said that logwood maybe rendered fast, by a preparation with fixed alkali.
(36)These 3 belong more to dyeing, yet might never theless, be used in printing, but the price is against them: — Kermes was much used formerly by dyers, but cochineal is now substituted.
(37) The great solvent power of alkalies, by; clearing away the fordes, will help to bring the particles of indigo more in contact with the cloth: the cause why cloth, which when dyed by indigo, is green, turns blue when exposed to the air, is thought to be owing to an attraction of the fixed air, by the alkali from the atmosphere rendering the salt unable to dissolve the indigo any further. — See Hellot on dyeing, but Dr. Lewis disputes Hellot's theory; he says acids will affect the same appearance, and that with vol. alk. it shews no green. Hellot however, shew s unless green appears it is not dissolved, hence fixed alkalies are only proper.
In the solution of indigo by alkalies, lime encreases the dissolving power, and if raisins be thrown into, the solution it throws up a copper-coloured ficum, which gives a dye in a moment: Prussian blue digested in an alkali, will produce a blue if what is coloured with it, lays a little while in a weak solution of copperas, but very inferior to indigo in durability. Dr. Lewis gives a recipe for making blue colour, but few practitioners will approve of his proportions.
(38) In drying plants between sheets of paper, the paper is at last tinged with colour; this is supposed to be occasioned by the allum used in making it — By rubbing a plant on blue paper, if acid, it turns the paper red, but green, if alkaline.
(39) Similar, in one respect, to the above obserration, it may be said, that among callico-printers a great point to attain in making colour, is to render the articles for the purpose of printing, all equally buoyant. It may be said too, that in all compositions there is the basis which is supposed to be unalterable in its effects; other matters may be added; but from them, certain modifications only, will be the result; hence this principle should be much thought of, that the more simple the basis of the composition it, the more easy is a variation to be made; and, in a contrary light, if what is supposed to be the basis, be compounded; as for instance,in a blue and yellow put together to make a green, it is highly probable that what may be added will disagree with either the blue or yellow more than tha other, and if more articles are added, the less certainty there can be of an effect.
In endeavouring to make a green, if a yellow feculence could be procured from a vegetable, as a blue one is, and that these two on being mixed, would perfectly unite, and be equally buoyant in whatever vehicle they may be used, there would be the stability required,for in this case, both partaking the same durable qualities, of course one would remain as long as the other, and thus the green might be said to be permanent; but at present there is a difficulty difficulty even in rendering the pencilling blue sufficiently buoyant, so as to print with it; this is however practised in the country, but the colour is generally uneven, and seems only practicable in dark grounds, from the latitude the grounding requires.
(40) If concentrated oil of vitriol be mixed with strong spirit of nitre, or of salt, the acid that is weakest will become very volatile, and throw off very elastic fumes; and if put into a close stopt bottle, would very probably burst it: the same will happen by mixing spirit of nitre and spirit of salt together; such mixtures should therefore only be made when wanted.
2. Vitriolated tartar and strong spirit of nitre, in equal quantities, dissolved, by being heated together in a mattrass, the stronger vitriolic acid will be displaced by the weaker nitrous one, and crystals of nitre will be formed from it: the same will happen if spirit of salt be used instead of nitre. This experiment seems to oppose the general opinion, that the vitriolic is stronger than the marine or nitrous, un less it be understood that quantity is observed more than quality.
3. If vitriolated tartar, or Glauber's salt, dissolved in water, be mixed with another solution consisting of calcareous earth, silver, mercury, lead, or tin, dissolved in the nitrous or marine acids, the vitriolic acid will leave the fixed alkali with which it was combined, and unite with the calcareous earth, or the metal, and sall to the bottom. Any acid may be used for this purpose, for here the vitriolic acid meets with such bodies as it cannot easily liquidate. This experiment shews, that the additament of water weakens the attraction of acids with alkalies or metals.
4. By dropping a solution of vitriolated tartar into lime, the acid will unite with the lime and precipitate with it into an indissoluble selenite, the alkali remaining pure in the water.
5. Green vitriol mixed with any solution containing substances which cannot be dissolved by the vitriolic acid, such at sac. saturni, the vitriol will be immediately decomposed, and combine itself with the lead, and thus become merely a solution of iron.
6. In the mixture of a solution of tin in aqua regia, and solution of sacrum saturni, the marine acid will quit the tin, and unite with the lead of the saccharum, the acetous, or, perhaps more properly, the vegetable acid combined with the lead, will at the same time be kept suspended, by the lead being unable to dissolve the tin; hence both being effectually decomposed, the mixture of course is useless.
7. Mild volatile alkali united with a quantity of fixed air, and poured into a solution of chalk in the nitrous or marine acid, will precipitate the earth, and form a true sal ammoniac; and if the whole be evaporated to dryness, and a considerable heat applied, the acid will again part with the alkali, and unite with the chalk.
8. By mixing together, and subliming equal parts of sal ammoniac and corrosive sublimate, they unite in such a manner as not to be separated without de composition: this compound is a very powerful solvent of all metallic substances, even gold itself.
9. By pouring vitriolic acid upon any salt, difficult to dissolve in water, it becomes then easily soluble; thus vitriolated tartar and cream of tartar may be dissolved.
It may be added, that on calcining fixed alkalies with the charcoal of, ashes of various vegetables, such as, southernwood, sage, rue, fern, pine-tops, tec. different coloured appearances will ensue, owing (it is supposed) to some proportion of the oily or phlogistic matter (on which colours depend) of the vegetable remaining in the ashes from which the salts are extracted: the salts thus obtained will produce different colours in the metallic solutions, precipitated by them, in this state.
Acid infusions heigthen red flowers in general, and many red, white and blue flowers are turned green, then yellow by alkalies, but which have little effect on yellow flowers, and some articles that alkalies turn red, purple or blue, are changed to a yellow by acids. — See Boyle and Lewis.
The affusion of ley will likewise procure from various flowers, insects or caterpillars, blue, purple or carnation colours, but in general, the flowers or plants that will not give a durable tinge with ley, are destroyed by it; there is however more hopes of fast colours being obtained from roots.
Among vegetables on which experiments have been tried, are the hemlock, producing a green: the wild lettuce and thorny sow-thistle, a yellow; the fungus tubolosus, a purple; and the celandine and wild patience, a blue.
In Linnæus's works, mention is made of a quantity of moss having rotted by the sea side, which produced a beautiful and durable red colour; and a kinds of moss are in use in Sweden for dyeing red.
Were the writer inclined, he could swell this work to any size, by extracts from various works, with experimental articles, but very few would be of real service, and the majority are far from being incontestible, (see note 28 in copper-work) the best however of the kind are to be found in Hellot and D'Apligny on Dyeing, Lewis's Notes to Neuman's Chemistry, his Commcrcium Philosophic cum Artium, and in L'Memoire d'Academe d'Art et Sciences, and various chemical treatises.
As for the Polygraphic Dictionary, School of Arts, School of Wisdom, and other collections of that nature, they contain too much trash to compensate for what little may be valuable.
The best account of drugs is to be found in Pomet's History, in Lewis's Notes to Neuman, and in the Chemical Dictionary.
It is here offered to set persons right in respect to colours, who affect to say, that as good or better, were done fifty or sixty years past,for as good were done two thousand years or more past; the very means as well as articles being of as ancient a standings indeed the origin can hardly be traced: so in printing, the method immemorial, has been by using allum, &c. to procure and fix the colouring particles; it may be even said, what we call new colours, have been produced many years past, under different appearances: if there be any real improvements, a principle one is in the mode of cleansing the cloth, and that perhaps is only in being rather more expeditiously performed than before. — See three or four leaves further on, and note 10 in the retrospect.
(41) In the vitriolic acid it brings hues from the bright pink to the flame, in aqua regia it brings a scarlet, in the marine it brings a dull colour.
Note, Where solution is mentioned it mould be understood as occasionally diluted.
The calx of tin (Sal Jovis) is used in dyeing to procure the fine scarlet from cochineal; and in this case is superior to allum. — See the process in Hellot on dyeing.
It may here be repeated (see note 24) that what will give colour to wool, will in some cases, give little if any, to silk, linen, or cotton, as wool is supposed to contain larger pores, and is of an alkaline quality; and in some cases it gives different colours, such as a purple to wool, while with linen or cotton it will be red.
Volatile alkalies heighten madder colour, though it hurts its permanency; but practices of this kind should not be made public, too much being done in that way, as is evident enough in country work.- See note 32 to copper-work.
*** It has been said this is partly applicable to, dyeing, for is discussing the theory of colours, it could hardly be avoided.
(42) Woad is of the same nature; archil is procured from a moss. — See notes 30 and 40.
(43) For the writer's sentiments on the inefficacy and impropriety of giving recipes for making colours, with some general reflection on chymick - printing, see the end of this section.Various suppositions respecting the fixity of colours by the use of astringents have been mentioned, though (as intimated Note 29 in copperwork) the theory generally adopted is contested; and it may here be added, that Mr. Macquer likewise contests it, he however observes, that when the earth of allum, after being conveyed to the cloth, is moistened, it imbibes the colouring particles of the bodies it meets with, though the cause of the attraction is unknown (31), (see note 28 on copper-work, and the article maddering, where what is here said is alluded to thus, according to the laws of affinities, the colouring particles would remain in the liquid in which they may be floating, such as the particles of madder, but that the earth of allum has a greater affinity with them, from their unctuous qualities, than they have with the water: (32) in cases where the earth of the allum does not attract the colouring particles, these particles may however have less affinity with water than those which need this earth to fix them; hence though they enter the pores, yet, from their minuteness, they are not retained, nd from their soapy qualities are soon washed off; but the unctuous quality above spoken of, and the phlogiston incorporated with it, is supposed by its union with the astringent to form that, cement often spoken of, though with dry substances such as zaffre, cinnabar, ochre, &c. it cannot be accomplished, however moistened the astringent may be, as the colouring particles would soon escape. (33)
Adverting to the doctrine of a vitriolated tartar (see introduction to maddering) Mr. Macquer observes he cannot suppose it perfectly stable(34) but the earth of allum or lime containing the phlogistic principles of colour, consequently those colours are produced, that ape incapable of being destroyed except by acids; these phlogistic principles (as before observed} are earths, oils, and salts, from the quantity and quality of which all colours result, and the simple addition of any salt to any oily vegetable colouring substance will either vary or expel its colour, because, any salt simple or compound, destroying by the laws of affinity the combination subsisting till then; the rays of light are differently refracted, there fore those substances whose colour cannot be altered by any salt, are those whose phlogiston is perfectly combined with their other principles; Indeed if we perfectly knew the nature of these combinations, it would help us in making artificial compositions, by analyzing these permanently tingeing substances, but not knowing (as observed before) the manner in which these principles are combined, as the utmost we can do, is only separating them by decomposing the colouring substances, we are under the necessity of endeavouring to improve on the known means with which nature has supplied us.
The juices of vegetables that will not give a fast colour, are liquids combined with certain oils, and being easily converted into a kind of soap, by alkalies or neutral salts, are soon removed; for in this case (turning to the laws of affinities) the colouring particles are so intimately united with the fluid in which they are suspended, that the earth of allunx will give their dyes no stability. It is however thought possible that substances may be rendered permanent in their colouring properties, that naturally are not so, could absorbent earths be in troduced into their pores, (35) or by adding acids to the colouring juices, in order to decompose the soap, and facilitate the union of the astringent with the colouring substance; not withstanding such decomposition might produce a change in some respect with the colour from animal juices colouring substances are rarely obtained; and could more be procured, it would be only going a further way about, as animal juices are derived from vegetable substances.
As the merely simple juices or fluids of animals and vegetables, rarely furnish materials for durable colours; and minerals, on account of their dryness are incapable of being attracted by astringents, we must seek those substances whose principles form, or help to form that unctuous and phlogistic gluten or cement which is the cause of permanency; and of these the most able to impart their colour are, kermes, cochineal, gumlac(36), madder, weld, &c. being both gummous and resinous, though in different degrees, or in other words possessing that phlogistic or inflammable property resulting from the union of oils, salts, and earths, on the various combinations of which, colour (as repeatedly said) depends, and which exhibit themselves when attracted by the application of proper astringents. Brazil, logwood, fustic, &c. being particularly resinous, their colouring substances are not so easily at tracted by astringents, and the colour they give is therefore of less permanency.
Yellows are to be procured from most leaves, barks, and woods, that on chewing discover an astringent taste, if treated in the same manner as weld; for the colours of most yellow flowers are durable, and are little affected by acids or alkalies, but other coloured flowers, as well as juices of plants, are rarely found to possess any permanently tingeing qualities, according to the experiments practised in common.
Respecting the general method of imparting permanent colour, the principle of the process is but simple, (see note 39 in copper-work) saline substances being (as said before) the chief means with which we are acquainted; thus, it may be observed, though a watery infusion of madder and other articles, will impart a tinge, yet washing will easily remove it; but that is not the case if the cloth have a saline article previously applied to it; there is however an exception to this rule in indigo, which it is difficult to dissolve (3[7]) except by alkalies, oil of vitriol, orpiment, or combinations of orpiment with) sulphur. When dissolved by alkalies, the colour is green, the colour naturally produced in vegetable blues by alkalies; but on exposing cloth dipped in it to the air, it turns blue: other exceptions in vegetables are mentioned elsewhere, at likewise the received opinion why they are so.
Proceeding further in the discussion o[f] colouring qualities, it may be observed, as the fixity of colours produced by different substances being mixed together, is proportionate to the power of such substances to withstand the weather, it would seem as if there were some method to de termine on their permanency, since it appears that the nitrous acid in general tends to heighten red colours, the vitriolic to crimson them, the marine to dull them, and alkalies to deepen them, (38) for, in this case, the colour produced by the nitrous acid, can remain no longer, when exposed to the air, than the spirit of nitre itself, because the nitre being drawn into the air, the colour must fade; and the disposition of colour to sade, must be in proportion to the permanency of the substances that produce them; colour, in this sense, being only colour as it is in possession of some substance to withold it; (39) but whatever substances are most proper, it is certain that on combining acids with alkalies, earths and minerals, effects are to be produced so infinitely various, that no rule can be precisely laid down to determine on what appearances will ensue on such combinations, or how this or that particular salt will affect, or be affected, by this or that substance; see a few experiments below: (40) however, among these various articles it is known that imperfect neutral salts act powerfully, the perfect ones but weakly; (in neutral salts the acid is the menstruum, and the alkali the basis, in imperfect neutrals one quality predominates thus, making a transition to what is relative to dyeing, see note 41; allum and sal ammoniac heighten cochineal, madder, logwood, brazil, fustic, &c. but Glauber's salt, salt-petre, common salt, and other neutrals, act less powerfully. A black is struck in the above substances (madder, logwood, &c.) by solutions of iron, likewise with sumach, galls, and other astringents; see note 25, solution of sacrum sat. acts as an alterant on red colours (as already said) solution of copper changes logwood purple to a blue, and is reconcileable to most blues; solution of the superior metals, gold, silver, and mercury, have the least pleasing, or least extensive effective powers; (see the chemical compendium) but in this respect, solution of tin in aqua regia takes the first rank, having a surprizing power of coagulating, the colouring matter of many articles; thus it procures from cochineal and gumlac a fine scarlet, from brazil a fine red; from logwood a beautiful purple; and from weld, fustick, turmerick, and many common yellow flowers more beautiful colours than can otherwise be obtained. It likewise changes to a red the colour of most blue flowers, but as a counter-balance it in some measure deadens madder, safflower, and archil, and changes the vitriolic tinctures of roses from a red to an indifferent green. (41)
Solution of fin, (it may be added) is likewise the best article to try the durable quality of a vegetable substance; for in general, where the solution does not destroy the colour, there is a probability of succeeding with it; but this solution will not combine with several substances, particularly with sugar of lead and cream of tartar (as already mentioned) neither will it unite with any calcareous earth, nor alkalies; but with allum it may, and is bettered by it.
The astringents proper for procuring the colour from madder (as already said) are allum and tartar, sacrum sat. solution of iron in a vegetable acid, &c. Iron liquor mixed with the red renders it, according to the quantity used, chocolate, pompadour, or brown red, (as observed before) but it must be carefully avoided, in preparing for pale reds.
In proving the fixity of colours, lemon-juice, vinegar, aqua fortis diluted, &c: are insufficient, their degree of acidity being very variable; but solutions of allum, white soap and red tartar are more proper.
For discharging colours, alkaline salts only are effective where solutions of tin have been used, or the cloth otherwise strongly coloured, and even then it requires grass bleaching; but vitriol dilated will discharge colour procured from logwood, where allum has been used, though with more difficulty if lampblack has been added.
ln the composition of penciling blue colour, by the alkaline salts being intimately blended with the indigo, the same purpose is answered as when allum or other astringents are previcufly applied in procuring madder colours, and by treating other articles in a similar manner, may therefore be considered as a basis for what is called chymick printing, or as bringing to a point what has been said concerning the procuring of colours by the simplest operations; that is, where a saline or an astringent substance and a vegetable colouring one can be united, a durable effect may probably be obtained, as a great number of different coloured feculæ or dregs, are very likely to be procured from various plants, similar to the process for procuring indigo, woad, or archil (42) or by precipitation in the manner of procuring calces of metals, or lakes from vegetables (see note 33, and end of note 40) and with proper solvents and thicknings might be made usetul in printing; but, as it is not the design of this treatise to create colour-makers (43) a deal must not be specifically said on this score (difficult as it certainly is, to steer between saying too little and too much) since common operators in that way (see the be ginning of this section) notwithstanding what has been, or may be said, as advising a better mode, would catch hold of any thing likely to be put into immediate practice, rather than think, a little and act in consequence.
This work not being addressed to those unacquainted with the use of drugs, &c. and it not being intended unnecessarily to swell it, the reader has been referred, (see note 40) to certain works for accounts of such articles; but, as this part of the section would by many be deemed inconclusive, without saying something of colouring drugs, a concise account is therefore annexed.
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