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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20) Non-colouring drugs, such as allum, tartar, and other astringents, are those which after being used, must undergo the process of boiling with certain colouring drugs, such as madder, weld, &c. &c. — This is a dyers term, and applied to articles used previous to colouring.
(21) The goodness of drugs is of the utmost concern, and well it is for those Printers who are not under the necessity of being restrained in this respect some by choice will not have the best even when needed, and others for reasons, too common in every station of life, must take what materials they can get.
(22) Pastes are made from flour and starch, and those articles as well as gums should be of the purest kind, when used as vehicles for carrying the colour. — Gums should be tried that no saline quality has been incorporaed with them by their having been before in a liquid state by any accident, particularly at sea.
(23)Lampblack is the least innocent in general from its oily quality, it should therefore be the lightest and blackest that can be had, which depends a great deal on its being well burnt, indeed it would often be the better for work if it were spared. Brazil is so innocent and the stain so easily removed, that little objection lays against it; it gives out its coleur best with hard water.
(24) The fielding, may be said; to be a process which rests with the foreman of the field, of which more is said further on.Drugs, and other Articles used in Colour-making.(20)
VEGETABLE Substances.
Gums arabic, senegal, tragacanth, mastic, lac, copal, and dragons blood, Madder, Indigo, Woad, Weld, Sumach, Fustic, Satinders, Annotto, Greenwood, Logwood, Brazil, Safflower, Barks, Flower, Starch, Bran, French berries, Resin, Ash, Vinegar, Verjuice, Crude tartar, Galls, &c.
MINERAL Substances, Salts and Earths.
White and yellow copperas, Orpiment, Arsenic, Corrosive sublimate, Roman vitriol, Vitriolic nitrous and marine acids, Salt-petre, Sal ammoniac, Verdigris, Tin, Pewter, Copper, Steel fileings, Antimony, Chalk, Tobacco pipe Clay, Lime, &c.
MISCELLANEOUS Substances.
Urine, Dung, Lamp-black, Acid of tar, Iron liquor, Hartshorn, (21) &c. Other articles might be added, but the above are chiefly in use. — See account of drugs, &c. further on.
The most durable Black and Purples, are brought up in madder, by the agency of iron liquor: Reds by allum, and occasionally tartar, salt of lead, and iron liquor, to vary the hue to a Pink, a Blossom, a Chocolate, etc. Yellows in weld, by allum and tartar: Olaves, Drabs, &c. by allum, tartar, and iron liquor: Doves, Browns, Greens &c. in Sumach, Fustick, Green wood, &c. by allum, tartar, and iron liquor: Blue, from Indigo or woad, by the agency of ash, lime, and orpiment.
Less permanent blacks, reds, purples, pearls, &c. are brought up in logwood, brazil, bark, &c. by the agency of iron liquor, galls, copperas, &c. but in skilful hands are to be much improved.
Chemical browns, buffs, pale greens, blue, salmon, and other colours, are by the agency of Tar acid. Iron liquor, Verdigris, Woad, Annotto, &c. brought up or struck with lime, and other colours, such as berry yellow, pencilled blue, procured from indigo, &c. require streaming or rincing in water only.
Note, As the above is only a summary, or elementary view of colours &c. a plan of a table for fixing proportions and shades to certain circumstances, is offered further on.
For conveying these mixtures to the cloth various articles are necessary to be used according to certain circumstances; these vehicles are gums and pastes (22); paste being of a more compact consistency than gum diluted, is used when lines or fine bodies or shades are required to be accurately expressed; diluted gum is more used in conveying solid bodies, in which no great accuracy of shape is required. Of gums, tragacanth has several advantages, and if properly managed, would distribute as well as the arabic, but this article as well as the oakgall is not always made the most of.
Lampblack(23), Brazil, &c. are necessary to deepen the colour of those mixtures, which would otherwise be too pale for printing, in some cases.
Attempting now to speak immediately of the colour- makers practice, the first consideration is in what degree of responsibility he stands, both as he has to act himself, and as he is concerned in the operation of others; which collectively considered, comprizes, 1. Ashing, Souring, &c. or the preparation for the reception of his mixtures. 2. Printing or the application of them, and 3. striking or fixing them, including rincing, streaming &c. of chemical ones, or. those not brought up in the copper, (24) for though colour-making is a distinct process from preparation, printing and boiling off, yet (as more fully considered further on,) being of the utmost consequence to a colour maker how they are performed, he may be said to be closely concerned in them.
The preparation has been spoken of, but for the sake of preserving a kind of formality in treating this part, whathasbeen said will 1st, be briefly recapitulated; 2dly, the nature and use of astringents will be next touched on; 3dly, some suggestions offered concerning colouring substances; including the result of various experiments; lastly, the application of his mixtures in the operation of printing,with notes and observations on the whole, more or less applicable to the subject, as the discussion of it leads the writer (according to the unrestrained mode in which he indulges himself) to deliver them. — See introduction, and note 2 in copper work.
It is therefore first observed, that as goods apt propriated for printing, though having under gone the processes in use among whitsterers, or bleachers by prosession, may nevertheless contract in the course of their removal from one place to another, foulnesses of various kinds: they are in general soaked or steeped in water, that any loose dirt may be removed; but there may be foulnesses which water only will not remove, of course something more, penetrating must be applied; if ash be used, it is presumed some unctuous substance is to be removed, which thft ash effects; but as the earth of the afli is supposed to be left in the cloth, which water will not easily remove, an acid is to be applied for that purpose, or sometimes to answer for ashing, and the cloth thus (aster the usual processes of planking, &c.)is rendered as pure and white as possible.
Here then commences the colour-makers immediate concern, and consequently the considerations respecting it, of which, it need hardly be said, the first is that of the nature or properties of those substances that are requisite to form a basis for the colour, chiefly in respect to the relation they hold with each other in view of pro ducing certain effects, according to the principles as established by nature, which principles in the first case are applicable only to chemical experiments (as exhibited in the tables of affinities and the rules immediately preceding them) but in advancing a step further, that knowledge must be considered as furnishing us with means of turning those experiments to advantage; therefore a colour maker when surrounded with his drugs &c. should look upon every article as an instrument in his hands, that ought not to be employed in vain; but this knowledge, to its proper extent (so rarely to be met with) is not to be acquired merely from self experience or the experience of others, and not only that such ingredients mixed or applied in such a manner will produce such effects, but why and upon what principle it is established, and by what laws it is governed: here is the spring that should give motion to this department; here is the basis on which the practice should be erected and diffuse itself; and here originates the grand source of a colour-maker's practice, namely, the knowledge of the laws of affinities, and the certain effects of combinations, previous to the adding of certain substances to each other: for in every mixture that can possibly be made, invariable effects according to those rules will naturally follow.
Thus beginning with the principal articles in a colour-maker's province (see note 39 at the end of copper-work) namely, salts or astringents; (see note below) it is necessary to know, according to those rules established by nature, how each species af fects any substance it may be offered to, and how it is affected in return; for all substances, mixed with othiers of different qualities, must cause a change in some respect or other, according to the sundamental principles as exhibited in the be ginning of the compendium of chemistry, (see rule 3) and this knowledge (it is again said) is the proper foundation or support of the practice of: Colour-making.
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