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Bottles of ink from Germany

An ink is a liquid containing various pigments and/or dyes used for coloring a surface to produce an image, text, or design. Ink is used for drawing and/or writing with a pen, brush or quill. Thicker inks, in paste form, are used extensively in letterpress and lithographic printing.

Ink is a complex medium composed of solvents, pigments, dyes, resins, lubricants, solubilizers, surfactants, particulate matter, fluorescers, and other materials. The components of inks serve many purposes; the ink’s carrier, colorants, and other additives are used to control flow and thickness of the ink and its appearance when dry.

Contents

Types of ink

Magnified line drawn by a fountain pen

Components and classifications of ink vary, but can commonly be broken into four components—colorants, vehicles (binders), additives, and carrier substances—and four classes—aqueous, liquid, pasty, and powdery.[1]

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Colorants

Pigmented inks are more frequently used than dyes because they are more color-fast, but they are also more expensive, are less consistent in color, and have less of a color range than dyes.[1]

Pigmented inks

Pigments are solid, opaque particles suspended in ink that provide color.[1] Pigment molecules are typically linked together in crystalline structures that are 0.1–2 µm in size and comprise 5–30 percent of the ink volume.[1]

Qualities such as hue, saturation, and lightness vary depending on the source and type of pigment.

Dyes in inks

Dye-based inks are generally much stronger than pigment-based inks and can produce much more color of a given density per unit of mass. However, because dyes are dissolved in the liquid phase, they have a tendency to soak into paper, thus making the ink less efficient and also potentially allowing the ink to bleed at the edges of an image, producing poor quality printing.[2]

To circumvent this problem, dye-based inks are made with solvents that dry rapidly or are used with quick-drying methods of printing, such as blowing hot air on the fresh print. Other methods include harder paper sizing and more specialized paper coatings. The latter is particularly suited to inks used in non-industrial settings (which must conform to tighter toxicity and emission controls), such as inkjet printer inks. Another technique involves coating the paper with a charged coating. If the dye has the opposite charge, it is attracted to and retained by this coating, while the solvent soaks into the paper. Cellulose, the material that paper is made of, is naturally charged, and so a compound that complexes with both the dye and the paper's surface will aid retention at the surface. Such a compound in common use in ink-jet printing inks is polyvinyl pyrrolidone.

An additional advantage of dye-based ink systems is that the dye molecules interact chemically with other ink ingredients. This means that they can benefit more than pigmented ink from optical brighteners and color-enhancing agents designed to increase the intensity and appearance of dyes. Because dyes get their color from the interaction of electrons in their molecules, the way in which the electrons can move is determined by the charge and extent of electron delocalization in the other ink ingredients. The color emerges as a function of the light energy that falls on the dye. Thus, if an optical brightener or color enhancer absorbs light energy and emits it through or with the dye, the appearance changes, as the spectrum of light re-emitted to the observer changes.

A more recent development in dye-based inks are dyes that react with cellulose to permanently color the paper. Such inks are not affected by water, alcohol, and other solvents. As such, their use is recommended to prevent frauds that involve removing signatures, such as check washing. This kind of ink is most commonly found in gel inks and in certain fountain pen inks.

History of ink

Ink drawing of Ganesha under an umbrella (early 19th century). Ink, called masi, an admixture of several chemical components, has been used in India since at least the 4th century BC.[3] The practice of writing with ink and a sharp pointed needle was common in early South India.[4] Several Jain sutras in India were compiled in ink.[5]

Many ancient cultures around the world have independently discovered and formulated inks for the purposes of writing and drawing. The knowledge of the inks, their recipes and the techniques for their production comes from archaeological analysis or from written text itself.

The history of Chinese inks can be traced back to the 12th century BC, with the utilization of natural plant (plant dyes), animal, and mineral inks based on such materials as graphite that were ground with water and applied with ink brushes. Evidence for the earliest Chinese inks, similar to modern inksticks, is around 256 BC in the end of the Warring States Period and produced using manual labour from soot and animal glue.[6]

The India ink used in ancient India since at least the 4th century BC was called masi which was made of burnt bones, tar, pitch, and other substances.[3][7] Indian documents written in Kharosthi with ink have been unearthed in Chinese Turkestan.[8] The practice of writing with ink and a sharp pointed needle was common in early South India.[4] Several Jain sutras in India were compiled in ink.[5]

In ancient Rome, atramentum was used. In an article for the Christian Science Monitor, Sharon J. Huntington describes these other historical inks:

About 1,600 years ago, a popular ink recipe was created. The recipe was used for centuries. Iron salts, such as ferrous sulfate (made by treating iron with sulfuric acid), were mixed with tannin from gallnuts (they grow on trees) and a thickener. When first put to paper, this ink is bluish-black. Over time it fades to a dull brown.

Scribes in medieval Europe (about AD 800 to 1500) wrote principally on parchment or vellum. One 12th century ink recipe called for hawthorn branches to be cut in the spring and left to dry. Then the bark was pounded from the branches and soaked in water for eight days. The water was boiled until it thickened and turned black. Wine was added during boiling. The ink was poured into special bags and hung in the sun. Once dried, the mixture was mixed with wine and iron salt over a fire to make the final ink.

The reservoir fountain pen dates back to 953, when Ma'ād al-Mu'izz, the caliph of Egypt, demanded a pen which would not stain his hands or clothes, and was provided with a pen which held ink in a reservoir and delivered it to the nib via gravity and capillary action.[9][10]

In the 15th century, a new type of ink had to be developed in Europe for the printing press by Johannes Gutenberg. Two types of ink were prevalent at the time: the Greek and Roman writing ink (soot, glue, and water) and the 12th century variety composed of ferrous sulfate, gall, gum, and water.[11] Neither of these handwriting inks could adhere to printing surfaces without creating blurs. Eventually an oily, varnish-like ink made of soot, turpentine, and walnut oil was created specifically for the printing press.

Modern ink applications

An example of ink used on a sticky note with a modern pen.

Up until a few years ago, consumers had very little interest in ink other than refills for their pens. Fountain pens became a novelty as the disposable ball point pen took over the market. The introduction of home computing led to home printing. Today, in developed nations, most residences and businesses have a printing capability. As a result, buying ink in the form of a printer cartridge has once again become a part of the day-to-day shopping experience, similar to buying a bottle of ink fifty years ago.

Ink refilling services for printer cartridges are offered by large, official printing companies as well as smaller, "unofficial" refill companies. Customers can often cut printing costs by using refill services from a refill company, or buying the new non-OEM (original equipment manufacturer) brands instead of refilling. The refilling of ink cartridges and the use of continuous ink supply systems for inkjet printers is very common in most countries, with the exception of the United States. As printer manufacturers control the type of competition that they allow on retail shelves to a great extent, devices to ease the use of refill inks are usually only available online.

Health and environmental aspects

There is a misconception that ink is non-toxic even if swallowed. Once ingested, ink can be hazardous to one's health. Certain inks, such as those used in printers, and even those found in a common pen can be harmful. Though ink will not easily cause death, inappropriate contact can cause effects such as severe headaches, skin irritation, or nervous system damage. These effects can be caused by solvents or by pigment constituents such as p-Anisidine, which is used in the process of creating the ink's color and shine.

Three main issues with the environmental impact of inks is the use of volatile organic compounds, heavy metals and non-renewable oils. Standards for the amount of heavy metals in ink have been set by some regulatory bodies.[12] There is a trend toward using vegetable oils rather than petroleum oils in recent years in response to a demand for better environmental sustainability.

Writing inks and preservation

The two most used black writing inks in history are carbon inks and iron gall inks. Both types create problems for preservationists.

Carbon inks

Chinese inkstick; carbon-based and made from soot and animal glue

Carbon inks were commonly made from lampblack or soot and a binding agent such as gum arabic or animal glue. The binding agent keeps the carbon particles in suspension and adhered to paper. The carbon particles do not fade over time even when in sunlight or when bleached. One benefit of carbon ink is that it is not harmful to the paper. Over time, the ink is chemically stable and therefore does not threaten the strength of the paper. Despite these benefits, carbon ink is not ideal for permanence and ease of preservation. Carbon ink has a tendency to smudge in humid environments and can be washed off a surface. The best method of preserving a document written in carbon ink is to ensure it is stored in a dry environment (Barrow 1972). Recently, carbon inks made from carbon nanotubes have been successfully created. They are similar in composition to the traditional inks in that they use a polymer to suspend the carbon nanotubes. These inks can be used in inkjet printers and produce electrically conductive patterns.[13]

Iron gall inks

Iron gall inks became prominent in the early 1100s; they were used for centuries and were widely thought to be the best type of ink. However, iron gall ink is corrosive and damages the paper it is on (Waters 1940). Items containing this ink can become brittle and the writing fades to brown. The original scores of Johann Sebastian Bach are threatened by the destructive properties of iron gall ink. The majority of his works are held by the German State Library, and about 25% of those are in advanced stages of decay (American Libraries 2000). The rate at which the writing fades is based on several factors, such as "the proportions of the ink ingredients, the amount deposited on the paper, and the composition of the paper" (Barrow 1972:16). The corrosion is caused by "two major degradation processes: acid catalysed hydrolysis and iron(II)-catalysed oxidation of cellulose" (Rouchon-Quillet 2004:389).

Treatment is a controversial subject. There is no treatment that will undo the damage already caused by the acidic ink. Deterioration can only be stopped or slowed for a period of time. There are some people who think it best not to treat the item at all for fear of the consequences. Others believe that non-aqueous procedures are the best solution. And then, there are some that believe an aqueous procedure may provide the answer for preserving items written with iron gall ink. Aqueous treatments include distilled water at different temperatures, calcium hydroxide, calcium bicarbonate, magnesium carbonate, magnesium bicarbonate, and calcium phytate. There are many possible side effects from these treatments. There can be mechanical damage, which would further weaken the paper. The color of the paper or ink may change and ink may bleed. Other consequences that might arise from aqueous treatment are a change of ink texture or the formation of on the surface of the ink (Reibland & de Groot 1999).

Iron gall inks are generally stored in a stable environment, because fluctuating relative humidity increases the rate at which formic acid, acetic acid and furan derivatives form in the material on which the ink was used. Sulfuric acid acts as a catalyst to cellulose hydrolysis, and iron (II) sulfate acts as a catalyst to cellulose oxidation. These chemical reactions physically weaken the paper, causing brittleness.[14]

Indelible ink

The word "indelible" means "cannot be removed". Some types of indelible ink have a very short shelf life because of the solvents used, which evaporate rapidly.

India, Philippines, Indonesia and other developing countries have used indelible ink the form of electoral stain to prevent electoral fraud. The Election Commission in India has used indelible ink for many elections. Indonesia used it in their last election in Aceh. In Mali, the ink is applied to the fingernail.

See also

References

  1. ^ a b c d Kipphan, Helmut (2001). Handbook of print media: technologies and production methods (Illustrated ed.). Springer. pp. 130–144. ISBN 3540673261. http://books.google.com/books?id=VrdqBRgSKasC. 
  2. ^ Castle Ink: How Dye-based Inks and Pigment-Based Inks Affect Printers, 2009.
  3. ^ a b Banerji, page 673
  4. ^ a b Sircar, page 62
  5. ^ a b Sircar, page 67
  6. ^ 蔡, 玫芬, 二、墨的發展史, National Chang-Hua Hall of Social Education 
  7. ^ "India ink." in Encyclopædia Britannica. 2008 Encyclopædia Britannica Inc.
  8. ^ Sircar, page 206
  9. ^ Paul Vallely, How Islamic Inventors Changed the World, The Independent, 11 March 2006.
  10. ^ Origins of the Fountain Pen, Foundation for Science Technology and Civilisation.
  11. ^ Many recipes for iron gall inks are featured in A booke of secrets: shewing diuers waies to make and prepare all sorts of inke... tr. out of Dutch into Englishe by W.P. [i.e. William Philip], London, 1596.
  12. ^ Canadian Printing Ink Manufacturers' Association
  13. ^ Simmons, Trevor (2007). "Large Area-Aligned Arrays from Direct Deposition of Single-Wall Carbon Nanotubes". J. Am. Chem. Soc. 129 (33): 10088–10089. doi:10.1021/ja073745e. http://pubs.acs.org/cgi-bin/article.cgi/jacsat/2007/129/i33/html/ja073745e.html. 
  14. ^ Henk J. Porck and René Teygeler, Preservation Science Survey (Washington, D.C.: Council on Library and Information Resources, 2000).
  • "Think Ink!" by Sharon J. Huntington, Christian Science Monitor, September 21, 2004, retrieved January 17, 2006.
  • "A History of Technology and Invention" by Maurice Audin, page 630.
  • Ainsworth, Mitchell, C., "Inks and Their Composition and Manufacture," Charles Griffin and Company Ltd, 1904.
  • Martín-Gil J, Ramos-Sánchez MC, Martín-Gil FJ and José-Yacamán M. "Chemical composition of a fountain pen ink". Journal of Chemical Education, 2006, 83, 1476–78
  • Banerji, Sures Chandra (1989). A Companion to Sanskrit Literature. Motilal Banarsidass. ISBN 812080063X.
  • Sircar, D.C. (1996).Indian epigraphy. Motilal Banarsidass. ISBN 8120811666.

Sources

  • N.a. (March 2000), "Bach Scores Turning to Dust in German Library", American Libraries: 24–25 
  • Barrow, W.J. (1972), Manuscripts and Documents: Their Deterioration and Restoration, Charlottesville: University of Virginia Press, ISBN 081390408 
  • Reiβ̞land, Birgit; de Groot, Suzan (August 15–21, 1999), "Ink Corrosion: Comparison of the Currently Used Aqueous Treatments for Paper Objects", Preprint from the 9th International Congress of IADA, pp. 121–129 
  • Rouchon-Quillet, V.; et al. (2004), "The Impact of Gallic Acid on Iron Gall Ink Corrosion", Applied Physics A 79: 389–392, doi:10.1007/s00339-004-2541-1 
  • Waters, C.E. (1940), Inks, U.S. Department of Commerce, National Bureau of Standards, United States Government Printing Office 

Further reading

  • Cueppers, Christoph (1989). "On the Manufacture of Ink." Ancient Nepal - Journal of the Department of Archaeology, Number 113, August-September 1989, pp. 1–7. [The Tibetan text and translation of a section of the work called, Bzo gnas nyer mkho'i za ma tog by 'Jam-mgon 'Ju Mi-pham-rgya-mtsho (1846–1912) describing various traditional Tibetan techniques of making inks from different sources of soot, and from earth, puffballs, dung, ser-sha - a yellow fungus, and the fruit of tsi dra ka (Ricinus communis).]

External links


1911 encyclopedia

Up to date as of January 14, 2010

From LoveToKnow 1911

INK (from Late Lat. encaustum, Gr. E-yKauo-rov, the purple ink used by Greek and Roman emperors, from EyKaiecv, to burn in), in its widest signification, a substance employed for producing graphic tracings, inscriptions, or impressions on paper or similar materials. The term includes two distinct conditions of pigment or colouring matter: the one fluid, and prepared for use with a pen or brush, as writing ink; the other a glutinous adhesive mass, printing ink, used for transferring to paper impressions from types, engraved plates and similar surfaces.

The ancient Egyptians prepared and used inks (Flinders Petrie discovered a papyrus bearing written characters as old as 2500 B.C.), and in China the invention of an ink is assigned to Tien-Tcheu, who lived between 2697 B.C. and 2597 B.C. These early inks were prepared from charcoal or soot mixed with gum, glue or varnish. Sepia, the black pigment secreted by the cuttle-fish, was used as a writing fluid by the Romans. The iron-gall ink, i.e. an ink prepared from an iron salt and tannin, appears to have been first described by the monk Theophilus, who lived in the 11th century A.D., although Pliny, in the 1st century A.D., was acquainted with the blackening of paper containing green vitriol by immersion in an infusion of nut-galls. Iron-gall inks, prepared by mixing extracts of galls, barks, &c., with green vitriol, subsequently came into common use, and in the 16th century recipes for their preparation were given in domestic encyclopaedias. Their scientific investigation was first made by William Lewis in 1748. The earlier iron-inks were essentially a suspension of the pigment in water. In the early part of the 19th century the firm of Stephens introduced the first of the so-called blue-black inks under the name of "Stephens' writing fluid." Solutions of green vitriol and tannin, coloured by indigo and logwood, were prepared, which wrote with a blue tint and blackened on exposure, this change being due to the production of the pigment within the pores of the paper. The "alizarine" inks, patented by Leonhardi in 1856, are similar inks with the addition of a little madder. The application of aniline colours to ink manufacture in England dates from Croc's patent of 1861.

Writing Inks. - Writing inks are fluid substances which contain colouring matter either in solution or in suspension, and commonly partly in both conditions. They may be prepared in all shades of colour, and contain almost every pigment which can be dissolved or suspended in a suitable medium. The most important of all varieties is black ink, after which red and blue are most commonly employed. Apart from colour there are special qualities which recommend certain inks for limited applications, such as marking inks, ineradicable ink, sympathetic ink, &c. A good writing ink for ordinary purposes should continue limpid, and flow freely and uniformly from the pen; it should not throw down a thick sludgy deposit on exposure to the air; nor should a coating of mould form on its surface. It should yield distinctly legible characters immediately on writing, not fading with age; and the fluid ought to penetrate into the paper without spreading, so that the characters will neither wash out nor be readily removed by erasure. Further, it is desirable that ink should be non-poisonous, that it should as little as possible corrode steel pens, that characters traced in it should dry readily on the application of blotting paper without smearing, and that the writing should not present a glossy, varnished appearance.

Tannin Inks. - These inks are prepared from galls, or other sources of tannin, and a salt of iron, with the addition of some agglutinant in the case of the so-called oxidized inks, or a colouring matter in the case of unoxidized inks. Such mixtures form the staple black inks of commerce; they are essentially an insoluble iron gallate in extremely fine division held in suspension in water or a soluble compound dissolved in water.

On long exposure to air, as in inkstands, or otherwise, tannin inks gradually become thick and ropy, depositing a slimy sediment. This change on exposure is inevitable, resulting from the gradual oxidation of the ferrous compound, and it can only be retarded by permitting access of air to as small surfaces as possible. The inks also have a tendency to become mouldy, an evil which may be obviated by the use of a minute proportion of carbolic acid; or salicylic acid may be used.

The essential ingredients of ordinary black ink are - first, tannin-yielding bodies, for which Aleppo or Chinese galls are the most eligible materials; second, a salt of iron, ferrous sulphate (green vitriol) being alone employed; and third, a gummy or mucilaginous agent to keep in suspension the insoluble tinctorial matter of the ink. For ink-making the tannin has first to be transformed into gallic acid. In the case of Aleppo galls this change takes place by fermentation when the solution of the galls is exposed to the air, the tannin splitting up into gallic acid and sugar. Chinese galls do not contain the ferment necessary for inducing this change; and to induce the process yeast must be added to their solution. To prepare a solution of Aleppo galls for ink-making, the galls are coarsely powdered, and intimately mixed with chopped straw. This mixture is thrown into a narrow deep oak vat, provided with a perforated false bottom, and having a tap at the bottom for drawing off liquid. Over the mixture is poured lukewarm water, which, percolating down, extracts and carries with it the tannin of the galls. The solution is drawn off and repeatedly run through the mixture to extract the whole of the tannin, the water used being in such proportion to the galls as will produce as nearly as possible a solution having 5% of tannin. The object of using straw in the extraction process is to maintain the porosity of the mixture, as powdered galls treated alone become so slimy with mucilaginous extract that liquid fails to percolate the mass. For each litre of the 5% solution about 45 grammes of the iron salt are used, or about loo parts of tannin for 90 parts of crystallized green vitriol. These ingredients when first mixed form a clear solution, but on their exposure to the air oxidation occurs, and an insoluble blue-black ferrosoferric gallate in extremely fine division, suspended in a coloured solution of ferrous gallate, is formed. To keep the insoluble portion suspended, a mucilaginous agent is employed, and those most available are gum senegal and gum arabic. An ink so prepared develops its intensity of colour only after some exposure; and after it has partly sunk into the paper it becomes oxidized there, and so mordanted into the fibre. As the first faintness of the characters is a disadvantage, it is a common practice to add some adventitious colouring matter to give immediate distinctness, and for that purpose either extract of logwood or a solution of indigo is used. When logwood extract is employed, a smaller proportion of extract of galls is required, logwood itself containing a large percentage of tannin. For making an unoxidized or blue-black ink indigo is dissolved in strong sulphuric acid, and the ferrous sulphate, instead of being used direct, is prepared by placing in this indigo solution a proper quantity of scrap iron. To free the solution from excess of uncombined acid, chalk or powdered limestone is added, whereby the free acid is fixed and a deposit of sulphate of lime formed. A solution so prepared, mixed with a tannin solution, yields a very limpid sea-green writing fluid, and as all the constituents remain in solution, no gum or other suspending medium is necessary. In consequence the ink flows freely, is easily dried and is free from the glossy appearance which arises through the use of gum.

China ink or Indian ink is the form in which ink was earliest prepared, and in which it is still used in China and Japan for writing with small brushes instead of pens. It is extensively used by architects, engineers and artists generally, and for various special uses. China ink is prepared in the form of sticks and cakes, which are rubbed down in water for use. It consists essentially of lamp-black in very fine condition, baked up with a glutinous substance; and the finer Oriental kinds are delicately perfumed. The following description of the manufacture as conducted in Japan is from a native source: "The body of the ink is soot obtained from pine wood or rosin, and lamp-black from sesamum oil for the finest sort. This is mixed with liquid glue made of ox-skin. This operation is effected in a large round copper bowl, formed of two spherical vessels, placed i in. apart, so that the space between can be filled up with hot water to prevent the glue from hardening during the time it is being mixed by hand with the lamp-black. The cakes are formed in wooden moulds, and dried between paper and ashes. Camphor, or a peculiar mixture of scents which comes from China, and a small quantity of carthamine (the red colouring substance of safflower), are added to the best kinds for improving the colour as well as for scenting the ink. There is a great difference both in price and in quality of the various kinds of ink, the finest article being rather costly." It is said that the size used in Chinese kinds is of vegetable origin.

Logwood Ink. - Under the name of chrome ink a black ink was discovered by Runge, which held out the promise of cheapness combined with many excellent qualities. It is prepared by dissolving 15 parts of extract of logwood in 900 parts of water, to which 4 parts of crystallized sodium carbonate are added. A further solution of i part of potassium chromate (not bichromate) in zoo parts of water is prepared, and is added very gradually to the other solution with constant agitation. The ink so obtained possesses an intense blue-black colour, flows freely and dries readily, is neutral in reaction and hence does not corrode steel pens, and adheres to and sinks into paper so that manuscripts written with it may be freely washed with a sponge without danger of smearing or spreading. It forms a good copying ink, and it possesses all the qualities essential to the best ink; but on exposure to air it very readily undergoes decomposition, the colouring matter separating in broad flakes, which swim in a clear menstruum. It is affirmed by Viedt that this drawback may be overcome by the use of soda, a method first suggested by Bottger.

Logwood forms the principal ingredient in various other black inks used, especially as copying ink. A very strong decoction of logwood or a strong solution of the extract with ammoniumalum yields a violet ink which darkens slowly on exposure. Such an ink is costly, on account of the concentrated condition in which the logwood must be used. If, however, a metallic salt is introduced, a serviceable ink is obtained with the expenditure of much less logwood. Either sulphate of copper or sulphate of iron may be used, but the former, which produces a pleasing blue-black colour, is to be preferred. The following is the formula most highly recommended for this ink. A clear solution of 20 kilos of extract of logwood in 200 litres of water is obtained, to which is added, with agitation, io kilos of ammonium-alum dissolved in 20 litres of boiling water. The solution is acidified with 0 2 kilo of sulphuric acid, which has the effect of preventing any deposit, and finally there is added a solution of 1-5 kilos of sulphate of copper dissolved in 20 litres of water. This compound is exposed to the air for a few days to allow the colour to develop by oxidation, after which it is stored in well-corked bottles. The acid condition of this ink has a corrosive influence on steel pens; in all other respects it is a most valuable writing fluid.

Aniline Inks. - Solutions of aniline dye-stuffs in water are widely used as inks, especially coloured varieties. They are usually fugitive. Nigrosine is a black ink, which, although not producing a black so intense as common ink, possesses various advantages. Being perfectly neutral, it does not attack pens; it can easily be kept of a proper consistency by making up with water; and its colour is not injuriously affected by the action of acids. Its ready flow from stylographic pens led to the name "stylographic ink." Other aniline inks are mentioned below.

Table of contents

Copying Ink

Ink which yields by means of pressure an impression, on a sheet of damped tissue paper, of characters written in it is called copying ink. Any ink soluble in water, or which retains a certain degree of solubility, may be used as copying ink. Runge's chrome ink, being a soluble compound, is, therefore, so available; and the other logwood inks as well as the ordinary ferrous gallate inks contain also soluble constituents, and are essentially soluble till they are oxidized in and on the paper after exposure to the air. To render these available as copying inks it is necessary to add to them a substance which will retard the oxidizing effect of the air for some time. For this purpose the bodies most serviceable are gum arabic or senegal, with glycerin, dextrin or sugar, which last, however, renders the ink sticky. These substances act by forming a kind of glaze or varnish over the surface of the ink which excludes the air. At the same time when the damp sheet of tissue paper is applied to the writing, they dissolve and allow a portion of the yet soluble ink to be absorbed by the moistened tissue. As copying ink has to yield two or more impressions, it is necessary that it should be made stronger, i.e. that it should contain more pigment or body than common ink. It, therefore, is prepared with from 30 to 40% less of water than non-copying kinds; but otherwise, except in the presence of the ingredients above mentioned, the inks are the same. Copying ink pencils consist of a base of graphite and kaolin impregnated with a very strong solution of an aniline colour, pressed into sticks and dried.

Red Ink

The pigment most commonly employed as the basis of red ink is Brazil-wood. Such an ink is prepared by adding to a strong decoction of the wood a proportion of stannous chloride (tin spirits), and thickening the resulting fluid with gum arabic. In some instances alum and cream of tartar are used instead of the stannous chloride. Cochineal is also employed as the tinctorial basis of red ink; but, while the resulting fluid is much more brilliant than that obtained from Brazilwood, it is not so permanent. A very brilliant red ink may be prepared by dissolving carmine in a solution of ammonia, but this preparation must be kept in closely stoppered bottles. A useful red ink may also be made by dissolving the rosein of Brook, Simpson and Spiller in water, in the proportion of I to from 150 to 200 parts.

Blue Ink

For the production of blue ink the pigment principally used is Prussian blue. It is first digested for two or three days with either strong hydrochloric acid, sulphuric acid or nitric acid, the digested mass is next very largely diluted with water, and after settling the supernatant liquid is siphoned away from the sediment. This sediment is repeatedly washed, till all traces of iron and free acid disappear from the water used, after which it is dried and mixed with oxalic acid in the proportion of 8 parts of Prussian blue to i of the acid, and in this condition the material is ready for dissolving in water to the degree of colour intensity necessary. An aniline blue ink may be prepared by dissolving i part of bleu de Paris in from 200 to 250 parts of water.

Marking Ink

The ink so called, used principally for marking linen, is composed of a salt of silver, usually the nitrate, dissolved in water and ammonia, with a little provisional colouring matter and gum for thickening. The colour resulting from the silver salt is developed by heat and light; and the stain it makes, although exceedingly obstinate, gradually becomes a faint brownish-yellow. The following yields a good marking ink. Equal parts of nitrate of silver and dry tartaric acid are triturated in a mortar, and treated with water, when a reaction takes place, resulting in the formation of tartrate of silver and the liberation of nitric acid. The acid is neutralized, and at the same time the silver tartrate is dissolved by the addition of ammonia, and this solution with colouring matter and gum forms the ink, which may be used with an ordinary steel pen.

Many vegetable juices, e g. of Coriaria thymifolia, Semecarpus anacardium, Anacardium occidentale (Cashew), are inks of this type.

Gold and silver inks are writing fluids in which gold and silver, or imitations of these metals, are suspended in a state of fine division. In place of gold, Dutch leaf or mosaic gold is frequently substituted, and bronze powders are used for preparing a similar kind of ink. The metallic foil isfirst carefully triturated into a fine paste with honey, after which it is boiled in water containing a little alkali, and then repeatedly washed in hot water and dried at a gentle heat. A solution is prepared consisting of i part of pure gum arabic and r part of soluble potash glass in 4 parts of distilled water, into which the requisite quantity of the metallic powder prepared is introduced. Owing to the superior covering nature of pure gold, less of the metal is required than is necessary in the case of silver and other foils. In general r part of foil to 3 or 4 parts of solution is sufficient. The metallic lustre of writing done with this solution may be greatly heightened by gently polishing with a burnishing point. Another gold ink depends upon the formation of purple of Cassius; the linen is mordanted with stannous chloride, and the gold applied as a gummy solution of the chloride.

Indelible or incorrodible ink is the name given to various combinations of lamp-black or other carbonaceous material with resinous substances used for writing which is exposed to the weather or to the action of strong acids or alkaline solutions. An ink having great resisting powers may be conveniently prepared by rubbing down Indian ink in common ink till the mixture flows easily from the pen. Other combinations have more the character of coloured varnishes.

Sympathetic inks are preparations used for forming characters which only become visible on the application of heat or of some chemical reagent. Many chemicals which form in themselves colourless solutions, but which develop colour under the influence of reagents, may be used as sympathetic ink, but they are of little practical utility. Characters written in a weak solution of galls develop a dark colour on being treated with a solution of copperas; or, vice versa, the writing may be done in copperas and developed by the galls solution. Writing done in various preparations develops colour on heating which fades as the paper cools. Among such substances are solutions of the chlorides of cobalt and of nickel. Very dilute solutions of the mineral acids and of common salt and a solution of equal parts of sulphate of copper and sal-ammoniac act similarly. Writing with rice water and developing with iodine was a device much used during the Indian Mutiny.

Printing Inks. - Printing inks are essentially mixtures of a pigment and a varnish. The varnish is prepared from linseed oil, rosin and soap; the oil must be as old as possible; the rosin may be black or amber; and the soap, which is indispensable since it causes the ink to adhere uniformly to the type and also to leave the type clean after taking an impression, is yellow, or turpentine soap for dark inks, and curd soap for light inks. The varnish is prepared as follows: The oil is carefully heated until it "strings" properly, i.e. a drop removed from the vessel on a rod, when placed upon a plate and the rod drawn away, forms a thread about a in. long. The rosin is carefully and slowly added and the mixture well stirred. The soap is then stirred in. The ink is prepared by mixing the varnish with the pigment, and grinding the mass to impalpable fineness either in a levigating mill or by a stone and muller. For black ink, lamp-black mixed with a little indigo or Prussian blue is the pigment employed; for wood engravings it may be mixed with ivory black, and for copper plates with ivory or Frankfurt black; for lithographic reproductions Paris black is used. Red inks are made with carmine or cochineal; red lead is used in cheap inks, but it rapidly blackens. Blue inks are made with indigo or Prussian blue; yellow with lead chromate or yellow ochre; green is made by mixing yellow and blue; and purple by mixing red and blue.

See C. A. Mitchell and T. C. Hepworth, Inks, their Composition and Manufacture (1904); S. Lehner, Ink Manufacture (1902); A. F. Gouillon, Encres et cirages (1906); L. E. Andes, Schreib-, Kopierund andere Tinten (1906).


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Wiktionary

Up to date as of January 15, 2010
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Definition from Wiktionary, a free dictionary

See also -ink

Contents

English

Pronunciation

Noun

Singular
ink

Plural
inks

ink (plural inks) (uncountable) and (countable)

A jar of ink.
  1. a pigment (or dye) based fluid used for writing, printing etc.
  2. black or dark coloured fluid ejected by squid, octopus etc, as a protective strategy

Translations

Verb

Infinitive
to ink

Third person singular
inks

Simple past
inked

Past participle
inked

Present participle
inking

to ink (third-person singular simple present inks, present participle inking, simple past and past participle inked)

  1. to apply ink
  2. to sign a document
  3. to tattoo someone

Translations

Anagrams

Related terms

See also


Simple English

[[File:|thumb|A bottle of ink]]

Ink is a liquid that we use to write, draw, print, or make marks. The word ink is from Latin and means "colored water". Ink is used in pens, in some computer printers, and in printing presses. In some countries, people write by using ink and brushes. People usually write or print using black ink, but ink can be any color. The first ink was used in Egypt about 2600 BC.

A disadvantage of many kinds of ink is that they may smudge when wet, spoiling the picture or writing.

The first inks were carbon inks, made from soot, which is 80% carbon. Later, in Europe, people used iron gall ink. This is the kind of ink Johann Sebastian Bach and Leonardo da Vinci used.

Ink in a ball point pen is held in a thin long cylinder (tube) inside the pen. The ink does not fall out of the cylinder as it sticks to the sides of the tube.

References

  • Martín-Gil, J.; Ramos-Sánchez, M.C.; Martín-Gil, F.J.; José-Yacamán, M. (2006), [Expression error: Unexpected < operator "Chemical composition of a fountain pen ink"], Journal of Chemical Education 83: 1476–1478 .bjn:Dawat


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