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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(78) The reader is reminded, proportions are in tentionally with-held, but particularly in chemical processes; note to prel. fug. for besides the reasons given, he will add here, that those recipes which he has procured, contradict each other. He however would willingly give information of certain venders of them and whose indigence it would even relieve.
(79) Bright colours on Kerseymere, and other woolen matters, are not the best on the score of permanency. (note) Brightners however are easily obtained, as said elsewhere.
A great sum (as before intimated) was given for a recipe for red, (at Nixon's, the writer thinks) because calx of tin was an ingredient, which acts as one of these brightners.
The writer knows of a first attempt to print hammer cloths, fabricated with a mixture of animal and vegetable matters; but the difference of the substances not being provided for, the endeavour failed (note 26 and 41) An ingenious artist (Naylor) has however done beautiful work on these articles, knowing how to provide for the mixture; as well as he has operated on the linings of carriages &c. and he now has deservedly the countenance of several of rank and fashion.
(80) Among the causes of the failure of Livesy and Co. may be included the irregularity and confusion Hall occasioned, as intimated elsewhere.
Brazil steeped in certain acids gives out a colour, which precipitated by an alkali, is a lake or inferior carmine
(81) Nitrous acid by its fumes, commonly called steaming, gives a dye to silk, which when dipped in an alkaline solution, is rendered orange; some other acids have similar power.
The fuming of dilute nitrous acid, is sometimes caused by its containing iron; which of course it muchbehoves the operator to be very careful of. The acid rendering many substances yellow, by its contact with them, is from the combustion which it causes.
Among the new acids that bid fair to be of the greatest advantage, are those of phosphorus and borax, from the fixity of their nature.
* The common peach or salmon is with ash and annatto.
Annatto colours with blue will hardly stand the lime.
(82) A chymist ac Old Ford, Middlesex, and a manufacturer of sal ammoniac, glaubers salts &c. likewise introduced this article to use about London.
When vinegar was used, it is a certainty the quality of it was not properly inquired into, and without a knowledge of chymistry the ammoniac cannot be managed always with certainty. But a deal depends on the nature of the thickening.
(83) In the prismatic colours, green is the point of contact between the extreme colours, and in this instance, some analogy may be found between permanent colours produced by dyeing, and those by the prism: the extreme colours or the most simple, being red and deep purple: but as the order of the rays approach to the green, they seem to coalesce, till they advance to the green itself, which is a direct union of the blue and yellow.
The artist mentioned note 79, is in possession of the best chymick green, of all she writer knows of.
(84) In a supplement, or else in the work hinted at note to prel. fug. the new terms, the new theories, and new facts, will be exhibited both distinctly and incorporated with what is of practical concern, properly explained and exemplified. (Perhaps he may give a specific views of proportions) As to what he has in this work attempted, he could here correct himself, especially in some practical matters, but he desires the reader, particularly the critical reader, so note what is observed at the back of the dedication, tion, and what is affixed to ths end of the work as an advertisement; only begging to repeat here the time he had to spare from his engagements. (See prelim. suggestions) was little, he durst not have risked expences ofeditors, revisors, &e. and lastly that he had to combat the in will of those who deemed the publication a mere divulging of practical secrets.
(85) In branning, the bran acts only on the colouring substance, which an alkali would do, but the alkali would disturb the acids that hold the colouring substance, of course the whole would be disturbed.Metallic calces, precipitates, and certain substances held in solution by acids, are here the common agents. Calces in general hare more attraction for, or, perhaps, rather are more attracted by animal or woollen substances (79) than vegetable, viz. linen, cotton and the like (calces of iron excepted) particularly if saturated with an alkali, from their affinity to them, as they leave the acid in which they are suspended, being at length thrown down, (note 33) Or it may be said, the solution of any metallic substance in an acid, produces the desired effect, by the substance it is applied to, having a power of decomposing it and joining the colouring part; therefore it may be observed the most likely circumstance in favour of forming chemical colours is the solution quitting its acid readily.
Where calces can be introduced along with the solvent, so as to form an union, it must be in consequence of the article intended to be coloured, having attraction for the calces; and hence the great advantage of woollen printing, as animal substances have stronger affinity to calces than vegetable. As to the circumstance of ironliquor causing a black as supposed by a deposition of its particles, (note 28) the new idea of a par tial solution of the cloth may be brought in to aid the operation.
The calces of gold, silver and mercury cause too much combustion to be rendered of proper subserviency; or in other words, their tendency to aflect too strongly the articles to which they are applied; while copper, lead, or bismuth approach the other extreme.
Many calces give a purple; Godfrey among his attempts has made several fine ones, note 4 to Prel. Sug. Ilet had one before the society for the encouragement of arts; but without under valuing the labours of any, and Godfrey's respectability as a chymist is well known, as well as the professional practice of Ilet, and others, unfortunately most chemical colours, unless they contain within themselves a proper buoyant, a buoyant or thickning is with difficulty incorporated with them, (note 49) and to temper them like aluminous and other solutions, destroys most of them at once, by the water taking hold of the solvent. Even the brilliancy makes them suspected. Another thing is the articles and processes being too expensive. Further, among attempts of this nature, from the power of the menstruum, not only an early injury will happen to the cloth, but a chance of the very prints being destroyed. (80) Hence solutions of animal and vegetable substances seem better calculated for service in general, but particularly for cloth of vegetable fabric.
Various acids (81) will formmany precipitates from brazil, but with solutions of tin the most general effects are obtained, and the most powerful is the solution in aqua regiae; om the goodness of which much however depends.
Among the effects thus produced, are,
1st, Red from cochineal: — The hue to be varied with tartar, sal ammoniac and other salts, [note 41) From safflower effects are likewise obtainable. Archil in this solution has likewise considerable effect, Among calces, bismuth may be used to advantage. On woollen, as before observed, most of the calces may.
2. Purple from logwood, and of some intensity.
3. Blue, by the addition of verdigris.
4. A lemon or salmon from annatto; and
5. An orange by addition of an alkali.*
6. Bright or pale blue green from verdigris and spirit of sal ammoniac, and sometimes tartar.
Vinegar was formerly used till the ammoniac was introduced by a chymist at Manchester (82)The vol. alk. should however be absolutely pure; but its great pungency is no proof of that see tests further on. A green has been beforesaid to be procurable from the proper solution; of indigo and the Saxon blue. Weld, brazil, ash, and copperas will form a green, if steeped all night, the hue and strength, of course varying with the proportions; but these decoctions or macerations should be in soft water, otherwise the ill-effects of selenite (vitriolic acid and lime) being decomposed will be too visible. Greens are likewise procurable by decoctions of various barks and woods by rincing. Among metals whose calces are green, nickel stands prominent, and is to be used to advantage.
Note. Respecting the procuring of a green whether from calces of metals, or precipitates, or lakes, from vegetables or animal substances (note 72) it is observed that whatever may be the boasts of operators, it must be allowed, none equal the green procured from indigo amd subse quent welding: the others in general, being blue or olave greens. In short, nature seems to say, a simple green shall not be allowed (83) or in the language of printers, a fast chymical green: for if we look round to all the operations of nature and art in producing a green, we shall find it the result of a combination of yellow, and blue, and the combination evidently to be traced out, and in many instances decomposed.
French berry yellow, whatever other substances may be added to it is so fugitive that it is rarely used now in respectable work.
Black of a most indelible nature, is procured by diluting a solution of silver in nitrous acid with distilled water, and a little gum; and im printing it on a cloth impregnated with solution of isinglass.
The most modern test of the strength of a colour is the dephlogisticated marine acid, (see Berthollet's treatise on it, and see note 21 to Gen. Reflect) as it operates very quickly, just as the air and sun does in a long time. The change it produces is attributed to a slow combustion, on the same principle as it operates when used for bleaching; but in discharging colours, if there be iron in them it is not so effective.
After the gradation the writer has hitherto affected, from the 1anguage most commonly in use in the printing business, to something closer to that of science, he would willingly rise to the most modern, which is daily getting ground: but this, were he ever so competent, he must not be diffusive on yet (84) for, so exhibit now what little he knows of the foundation on which it is raised, would be supposing an acquaintance with principles to exist among those to whom he writes, that certainty does not (especially about London) which he here means to mention for the last time. However, what he now advances, he does only with a view to stimulate those few who know something of the old chymistry, to a beter acquaintance with the new.
The greatest agent in most natural operations is called oxygen, and its effects oxygenation; which is, that certain substances in consequence of certain powers of attraction or affinity absorb the vital air of the atmosphere.
The diminution of oxygen, or vital air, in the oxyd or calx, and of Hydrogen, or inflammable air, in the colouring substance, is the cause as colouring effects. If the oxygen combine with the colouring particles, the hydrogen is retained and consequently the colour; but if the hydrogen be disengaged, the carbone, or charcoal, manifests itself by the colour appearing brown or yellow (this theory is applicable to what is called foxing the purples as just spoken of) for carbons being contained along with hydrogen in all vegetable substances, according to the proportion of carbone left by any operation it will be seen by the hue it leaves. Indigo has more carbone in its composition than must substances.
Thus the processes of ashing, souring, raising the colour, fielding, &c. are accounted for by oxygenation having taken place, that is, an ab sorption of vital air; and its attendant and consequent combustion of the colouring matter (85) or, in some cases, as in unbleached flax, silk, thread, or cloth, what may be called the discolouring matter.
Of new terms, the chief acids, vitriolic, marine, and nitrous, are called sulphuric, muriatic, and nitric. Allum is sulphat of alumine. Copperas acetite of copper, &c. &c. The combinations of vitriolic acid with various other substances are sulphats or sulphites; marine acid, muriats, &c. (see note preceding) as already alluded to before.
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