Misplaced Pages

#947052

67-442: Ink can be a complex medium, composed of solvents , pigments, dyes , resins , lubricants , solubilizers , surfactants , particulate matter , fluorescents , and other materials. The components of inks serve many purposes; the ink's carrier, colorants, and other additives affect the flow and thickness of the ink and its dry appearance. Many ancient cultures around the world have independently discovered and formulated inks due to

134-458: A color range than dyes. Pigments are solid, opaque particles suspended in ink to provide color. Pigment molecules typically link together in crystalline structures that are 0.1–2 μm in size and comprise 5–30 percent of the ink volume. Qualities such as hue , saturation , and lightness vary depending on the source and type of pigment.Solvent-based inks are widely used for high-speed printing and applications that require quick drying times. And

201-776: A pestle and mortar , then pour it into a ceramic dish to dry. To use the dry mixture, a wet brush would be applied until it reliquified. The manufacture of India ink was well-established by the Cao Wei dynasty (220–265 AD). Indian documents written in Kharosthi with ink have been unearthed in Xinjiang . The practice of writing with ink and a sharp pointed needle was common in early South India. Several Buddhist and Jain sutras in India were compiled in ink. Cephalopod ink , known as sepia , turns from dark blue-black to brown on drying, and

268-402: A baptismal font that continues to exist to this day, known today as the "Sultan's Baptistry". According to this legend al-Mu'izz abdicated the throne in favor of his son, and spent the rest of his life in a monastery. This story is rejected by Muslim historians such as Ahmad Zaki Pasha and Muhammad Abdullah Enan. Sources differ on al-Mu'izz's consorts. According to one version, he married

335-445: A catalyst to cellulose oxidation. These chemical reactions physically weaken the paper, causing brittleness . Indelible means "un-removable". Some types of indelible ink have a very short shelf life because of the quickly evaporating solvents used. India, Mexico, Indonesia, Malaysia and other developing countries have used indelible ink in the form of electoral stain to prevent electoral fraud . Election ink based on silver nitrate

402-404: A change of ink texture or formation of plaque on the surface of the ink (Reibland & de Groot 1999). Iron gall inks require storage in a stable environment, because fluctuating relative humidity increases the rate that formic acid, acetic acid, and furan derivatives form in the material the ink was used on. Sulfuric acid acts as a catalyst to cellulose hydrolysis, and iron (II) sulfate acts as

469-425: A common pen can be harmful. Though ink does not easily cause death, repeated skin contact or ingestion can cause effects such as severe headaches, skin irritation, or nervous system damage. These effects can be caused by solvents, or by pigment ingredients such as p -Anisidine , which helps create some inks' color and shine. Three main environmental issues with ink are: Some regulatory bodies have set standards for

536-465: A cousin of his, who gave him two sons, including his successor al-Aziz. Other sources report that his main consort ( al-Sayyida al-Mu'iziyya ), and mother of al-Aziz, was a slave-girl ( jarya ) from Mahdia named Durzan, who due to her beautiful singing voice (although this may simply reflect a common stereotype about jarya s) was nicknamed taghrīd ("twittering"). Al-Mu'izz had several other sons, but two are known by name: Tamim and Abdallah , who

603-448: A dielectric constant (more accurately, relative static permittivity ) greater than 15 (i.e. polar or polarizable) can be further divided into protic and aprotic. Protic solvents, such as water , solvate anions (negatively charged solutes) strongly via hydrogen bonding . Polar aprotic solvents , such as acetone or dichloromethane , tend to have large dipole moments (separation of partial positive and partial negative charges within

670-657: A drier. The earliest Chinese inks may date to four millennia ago, to the Chinese Neolithic Period . These included plant, animal, and mineral inks, based on such materials as graphite ; these were ground with water and applied with ink brushes . Direct evidence for the earliest Chinese inks, similar to modern inksticks , is found around 256 BC, in the end of the Warring States period ; being produced from soot and animal glue . The preferred inks for drawing or painting on paper or silk are produced from

737-407: A layer on top of water. Important exceptions are most of the halogenated solvents like dichloromethane or chloroform will sink to the bottom of a container, leaving water as the top layer. This is crucial to remember when partitioning compounds between solvents and water in a separatory funnel during chemical syntheses. Often, specific gravity is cited in place of density. Specific gravity

SECTION 10

#1732772104948

804-444: A little more ink than was necessary. Hence al-Mu'izz ordered that it should be adjusted slightly, and he did this. He brought forward the pen and behold, it turned out to be a pen which can be turned upside down in the hand and tipped from side to side, and no trace of ink appears from it. When a secretary takes up the pen and writes with it, he is able to write in the most elegant script that could possibly be desired; then, when he lifts

871-450: A neutral process. When one substance dissolves into another, a solution is formed. A solution is a homogeneous mixture consisting of a solute dissolved into a solvent. The solute is the substance that is being dissolved, while the solvent is the dissolving medium. Solutions can be formed with many different types and forms of solutes and solvents. Solvents can be broadly classified into two categories: polar and non-polar . A special case

938-421: A peroxide compound. The process of peroxide formation is greatly accelerated by exposure to even low levels of light, but can proceed slowly even in dark conditions. Unless a desiccant is used which can destroy the peroxides, they will concentrate during distillation , due to their higher boiling point . When sufficient peroxides have formed, they can form a crystalline , shock-sensitive solid precipitate at

1005-400: A polymer to suspend the carbon nanotubes. These inks can be used in inkjet printers and produce electrically conductive patterns. Iron gall inks became prominent in the early 12th century; they were used for centuries and were widely thought to be the best type of ink. However, iron gall ink is corrosive and damages paper over time (Waters 1940). Items containing this ink can become brittle and

1072-531: A reservoir. In the 15th century, a new type of ink had to be developed in Europe for the printing press by Johannes Gutenberg . According to Martyn Lyons in his book Books: A Living History , Gutenberg's dye was indelible, oil-based, and made from the soot of lamps (lamp-black) mixed with varnish and egg white. Two types of ink were prevalent at the time: the Greek and Roman writing ink (soot, glue, and water) and

1139-458: A single bottle. Low-volume users should acquire only small amounts of peroxide-prone solvents, and dispose of old solvents on a regular periodic schedule. Al Muizz States People Centers Other Abu Tamim Ma'ad al-Mu'izz li-Din Allah ( Arabic : أبو تميم معد المعزّ لدين الله , romanized :  Abū Tamīm Maʿad al-Muʿizz li-Dīn Allāh , lit.   'Glorifier of

1206-424: A solute during a chemical reaction. Kosower 's Z scale measures polarity in terms of the influence of the solvent on UV -absorption maxima of a salt, usually pyridinium iodide or the pyridinium zwitterion . Donor number and donor acceptor scale measures polarity in terms of how a solvent interacts with specific substances, like a strong Lewis acid or a strong Lewis base. The Hildebrand parameter

1273-401: A spreadsheet of values, or HSP software. A 1:1 mixture of toluene and 1,4 dioxane has δD, δP and δH values of 17.8, 1.6 and 5.5, comparable to those of chloroform at 17.8, 3.1 and 5.7 respectively. Because of the health hazards associated with toluene itself, other mixtures of solvents may be found using a full HSP dataset. The boiling point is an important property because it determines

1340-439: 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

1407-449: A tool for the selection of solvents based on a principal component analysis of solvent properties. The Hansen solubility parameter (HSP) values are based on dispersion bonds (δD), polar bonds (δP) and hydrogen bonds (δH). These contain information about the inter-molecular interactions with other solvents and also with polymers, pigments, nanoparticles , etc. This allows for rational formulations knowing, for example, that there

SECTION 20

#1732772104948

1474-901: A united manner. The polarity, dipole moment, polarizability and hydrogen bonding of a solvent determines what type of compounds it is able to dissolve and with what other solvents or liquid compounds it is miscible . Generally, polar solvents dissolve polar compounds best and non-polar solvents dissolve non-polar compounds best; hence " like dissolves like ". Strongly polar compounds like sugars (e.g. sucrose ) or ionic compounds, like inorganic salts (e.g. table salt ) dissolve only in very polar solvents like water, while strongly non-polar compounds like oils or waxes dissolve only in very non-polar organic solvents like hexane . Similarly, water and hexane (or vinegar and vegetable oil) are not miscible with each other and will quickly separate into two layers even after being shaken well. Polarity can be separated to different contributions. For example,

1541-558: A verse in the Gospel of Matthew which says: If ye have faith as a grain of mustard seed, ye shall say unto this mountain, Remove hence to yonder place; and it shall remove; and nothing shall be impossible unto you. According to Coptic sources, Pope Abraham of Alexandria ordered the Coptic community to keep vigil and to pray for three days and nights. On the third night, Pope Abraham had a dream in which Mary directed him to search for Simon

1608-551: Is dissolved into another, a solution is formed. This is opposed to the situation when the compounds are insoluble like sand in water. In a solution, all of the ingredients are uniformly distributed at a molecular level and no residue remains. A solvent-solute mixture consists of a single phase with all solute molecules occurring as solvates (solvent-solute complexes ), as opposed to separate continuous phases as in suspensions, emulsions and other types of non-solution mixtures. The ability of one compound to be dissolved in another

1675-555: Is a good HSP match between a solvent and a polymer. Rational substitutions can also be made for "good" solvents (effective at dissolving the solute) that are "bad" (expensive or hazardous to health or the environment). The following table shows that the intuitions from "non-polar", "polar aprotic" and "polar protic" are put numerically – the "polar" molecules have higher levels of δP and the protic solvents have higher levels of δH. Because numerical values are used, comparisons can be made rationally by comparing numbers. For example, acetonitrile

1742-464: Is a quantum chemically derived charge density parameter. This parameter seems to reproduce many of the experimental solvent parameters (especially the donor and acceptor numbers) using this charge decomposition analysis approach, with an electrostatic basis. The ϸ parameter was originally developed to quantify and explain the Hofmeister series by quantifying polyatomic ions and the monatomic ions in

1809-510: Is an acceptable predictor of the solvent's ability to dissolve common ionic compounds , such as salts. Dielectric constants are not the only measure of polarity. Because solvents are used by chemists to carry out chemical reactions or observe chemical and biological phenomena, more specific measures of polarity are required. Most of these measures are sensitive to chemical structure. The Grunwald–Winstein m Y scale measures polarity in terms of solvent influence on buildup of positive charge of

1876-568: Is below 100 °C (212 °F), so objects such as steam pipes, light bulbs , hotplates , and recently extinguished bunsen burners are able to ignite its vapors. In addition some solvents, such as methanol, can burn with a very hot flame which can be nearly invisible under some lighting conditions. This can delay or prevent the timely recognition of a dangerous fire, until flames spread to other materials. Ethers like diethyl ether and tetrahydrofuran (THF) can form highly explosive organic peroxides upon exposure to oxygen and light. THF

1943-827: Is defined as the density of the solvent divided by the density of water at the same temperature. As such, specific gravity is a unitless value. It readily communicates whether a water-insoluble solvent will float (SG < 1.0) or sink (SG > 1.0) when mixed with water. Multicomponent solvents appeared after World War II in the USSR , and continue to be used and produced in the post-Soviet states. These solvents may have one or more applications, but they are not universal preparations. Most organic solvents are flammable or highly flammable, depending on their volatility . Exceptions are some chlorinated solvents like dichloromethane and chloroform . Mixtures of solvent vapors and air can explode . Solvent vapors are heavier than air; they will sink to

2010-468: Is elemental mercury , whose solutions are known as amalgams ; also, other metal solutions exist which are liquid at room temperature. Generally, the dielectric constant of the solvent provides a rough measure of a solvent's polarity. The strong polarity of water is indicated by its high dielectric constant of 88 (at 0 °C). Solvents with a dielectric constant of less than 15 are generally considered to be nonpolar. The dielectric constant measures

2077-446: Is known as solubility; if this occurs in all proportions, it is called miscible . In addition to mixing, the substances in a solution interact with each other at the molecular level. When something is dissolved, molecules of the solvent arrange around molecules of the solute. Heat transfer is involved and entropy is increased making the solution more thermodynamically stable than the solute and solvent separately. This arrangement

Ink - Misplaced Pages Continue

2144-412: Is mediated by the respective chemical properties of the solvent and solute, such as hydrogen bonding , dipole moment and polarizability . Solvation does not cause a chemical reaction or chemical configuration changes in the solute. However, solvation resembles a coordination complex formation reaction, often with considerable energetics (heat of solvation and entropy of solvation) and is thus far from

2211-483: Is much more polar than acetone but exhibits slightly less hydrogen bonding. If, for environmental or other reasons, a solvent or solvent blend is required to replace another of equivalent solvency, the substitution can be made on the basis of the Hansen solubility parameters of each. The values for mixtures are taken as the weighted averages of the values for the neat solvents. This can be calculated by trial-and-error ,

2278-440: Is normally more likely to form such peroxides than diethyl ether. One of the most susceptible solvents is diisopropyl ether , but all ethers are considered to be potential peroxide sources. The heteroatom ( oxygen ) stabilizes the formation of a free radical which is formed by the abstraction of a hydrogen atom by another free radical. The carbon-centered free radical thus formed is able to react with an oxygen molecule to form

2345-569: Is that carbon ink does not harm paper. Over time, the ink is chemically stable and therefore does not threaten the paper's strength. Despite these benefits, carbon ink is not ideal for permanence and ease of preservation. Carbon ink tends to smudge in humid environments and can be washed off surfaces. The best method of preserving a document written in carbon ink is to store it in a dry environment (Barrow 1972). Recently, carbon inks made from carbon nanotubes have been successfully created. They are similar in composition to traditional inks in that they use

2412-497: Is the square root of cohesive energy density . It can be used with nonpolar compounds, but cannot accommodate complex chemistry. Reichardt's dye, a solvatochromic dye that changes color in response to polarity, gives a scale of E T (30) values. E T is the transition energy between the ground state and the lowest excited state in kcal/mol, and (30) identifies the dye. Another, roughly correlated scale ( E T (33)) can be defined with Nile red . Gregory's solvent ϸ parameter

2479-676: The Abbasids to counterattack. The territory fell to the Fatimids in 969 without any great resistance. After he had secured his position, al-Mu'izz transferred the royal residence from Al-Mansuriya to the newly founded city of Qāhirat al-Muʿizz "al-Mu'izz's Victory", i.e. , Cairo , thereby shifting the centre of gravity of the Fatimid realm eastwards. In Egypt, several attacks by the Carmathians had to be fought off (972–974) before

2546-641: The Coptic New Year , was permitted, though prohibitions on some of the activities, such as fire illumination and water splashing, were instituted. The relationship between al-Mu'izz and the Copts of Egypt has been the subject of a number of legends written later by Coptic Christians. One such legend involves al-Mu'izz challenging Pope Abraham of Alexandria to move the Mokattam mountain in Cairo, recalling

2613-600: The Fatimids , under the third caliph, al-Mansur bi-Nasr Allah ( r.  946–953 ), had defeated the rebellion of Abu Yazid , they began, under his son al-Mu'izz, to turn their attentions back to their ambition of establishing their caliphate throughout the Islamic world and overthrowing the Abbasids . Although the Fatimids were primarily concerned with Egypt and the Near East, there were nevertheless campaigns fought in

2680-538: The Kamlet-Taft parameters are dipolarity/polarizability ( π* ), hydrogen-bonding acidity ( α ) and hydrogen-bonding basicity ( β ). These can be calculated from the wavelength shifts of 3–6 different solvatochromic dyes in the solvent, usually including Reichardt's dye , nitroaniline and diethylnitroaniline . Another option, Hansen solubility parameters , separates the cohesive energy density into dispersion, polar, and hydrogen bonding contributions. Solvents with

2747-1017: The Latin solvō , "loosen, untie, solve") is a substance that dissolves a solute, resulting in a solution . A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid . Water is a solvent for polar molecules , and the most common solvent used by living things; all the ions and proteins in a cell are dissolved in water within the cell. Major uses of solvents are in paints, paint removers, inks, and dry cleaning. Specific uses for organic solvents are in dry cleaning (e.g. tetrachloroethylene ); as paint thinners ( toluene , turpentine ); as nail polish removers and solvents of glue ( acetone , methyl acetate , ethyl acetate ); in spot removers ( hexane , petrol ether); in detergents ( citrus terpenes ); and in perfumes ( ethanol ). Solvents find various applications in chemical, pharmaceutical , oil, and gas industries, including in chemical syntheses and purification processes When one substance

Ink - Misplaced Pages Continue

2814-585: The Maghreb and against the Umayyads of Spain. At the same time, Fatimid raids on Italy enabled naval superiority in the Western Mediterranean to be affirmed, at the expense of Byzantium , even capturing Sicily for a period of time. The way to Egypt was then clear for the Fatimids, the more so given the state of crisis that the incumbent Ikhshidid dynasty found itself in and the inability of

2881-558: The 12th century variety composed of ferrous sulfate, gall, gum, and water. 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. Ink formulas vary, but commonly involve two components: Inks generally fall into four classes: Pigment inks are used more frequently than dyes because they are more color-fast, but they are also more expensive, less consistent in color, and have less of

2948-663: The Religion of God'; 26 September 932 – 19 December 975) was the fourth Fatimid caliph and the 14th Ismaili imam , reigning from 953 to 975. It was during his caliphate that the center of power of the Fatimid dynasty was moved from Ifriqiya (modern Tunisia ) to Egypt. The Fatimids founded the city of Cairo ( al-Qāhirah , "the Victorious") in 969 as the new capital of the Fatimid Caliphate in Egypt. After

3015-647: The Tanner . The legend continues that with the prayers of the Coptic community, led by the Pope and Simon, the Mokattam mountain moved. This story is recounted in the book History of the Patriarchs of Alexandria , written by Severus Ibn al-Muqaffa . Later Coptic sources would further claim that this miracle led al-Mu'izz to convert to Christianity, and that he was baptized at the church of Saint Mercurius in Cairo in

3082-575: The amount of heavy metals in ink. There is a trend toward vegetable oils rather than petroleum oils in recent years in response to a demand for better environmental sustainability performance. Ink uses up non-renewable oils and metals, which has a negative impact on the environment. Carbon inks were commonly made from lampblack or soot and a binding agent such as gum arabic or animal glue . The binding agent keeps carbon particles in suspension and adhered to paper. Carbon particles do not fade over time even when bleached or when in sunlight. One benefit

3149-505: The best solution. Yet others think an aqueous procedure may preserve items written with iron gall ink. Aqueous treatments include distilled water at different temperatures, calcium hydroxide, calcium bicarbonate, magnesium carbonate, magnesium bicarbonate, and calcium hyphenate. There are many possible side effects from these treatments. There can be mechanical damage, which further weakens the paper. Paper color or ink color may change, and ink may bleed. Other consequences of aqueous treatment are

3216-456: The bottom and can travel large distances nearly undiluted. Solvent vapors can also be found in supposedly empty drums and cans, posing a flash fire hazard; hence empty containers of volatile solvents should be stored open and upside down. Both diethyl ether and carbon disulfide have exceptionally low autoignition temperatures which increase greatly the fire risk associated with these solvents. The autoignition temperature of carbon disulfide

3283-411: The canon law of the Fatimid Caliphate, was completed under al-Mu'izz. Coptic Christians were allowed a large degree of freedom under al-Mu'izz. Copts were among those appointed to the highest offices of the empire and were allowed to freely practice their religion. Under Al-Mu'izz, the viceroy of Syria was Quzman Ibn Nima, a Copt who remained a Christian. The Nayrouz festival, the celebration of

3350-428: 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

3417-538: The inclusion of TiO2 powder provides superior coverage and vibrant colors. 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, potentially allowing the ink to bleed at the edges of an image. 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

SECTION 50

#1732772104948

3484-495: The intensity and appearance of dyes. Dye-based inks can be used for anti-counterfeit purposes and can be found in some gel inks, fountain pen inks, and inks used for paper currency. These inks react with cellulose to bring about a permanent color change. Dye based inks are used to color hair. 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 digital printers, and even those found in

3551-412: The mouth of a container or bottle. Minor mechanical disturbances, such as scraping the inside of a vessel, the dislodging of a deposit, or merely twisting the cap may provide sufficient energy for the peroxide to detonate or explode violently. Peroxide formation is not a significant problem when fresh solvents are used up quickly; they are more of a problem in laboratories which may take years to finish

3618-640: The need to write and draw. The recipes and techniques for the production of ink are derived from archaeological analyses or from written texts itself. The earliest inks from all civilizations are believed to have been made with lampblack , a kind of soot , easily collected as a by-product of fire. Ink was used in Ancient Egypt for writing and drawing on papyrus from at least the 26th century BC. Egyptian red and black inks included iron and ocher as pigments, in addition to phosphate , sulfate , chloride , and carboxylate ions, with lead also used as

3685-440: The paper, and paper composition (Barrow 1972:16). Corrosion is caused by acid catalyzed hydrolysis and iron(II)-catalysed oxidation of cellulose (Rouchon-Quillet 2004:389). Treatment is a controversial subject. No treatment undoes damage already caused by acidic ink. Deterioration can only be stopped or slowed. Some think it best not to treat the item at all for fear of the consequences. Others believe that non-aqueous procedures are

3752-512: The pen off the sheet of writing material, it holds in the ink. I observed that it was a wonderful piece of work, the like of which I had never imagined I would ever see. Fatimid literature rose to a degree of prominence in the period of al-Mu'izz with the emergence of skilled poets like Ibn Hani , who was often compared to al-Mutanabbi , and hailed as the Mutanabbi of the West. Da'a'im al-Islam ,

3819-459: The resin of the pine trees between 50 and 100 years old. The Chinese inkstick is produced with a fish glue, whereas Japanese glue (膠 nikawa ) is from cow or stag. India ink was invented in China, though materials were often traded from India, hence the name. The traditional Chinese method of making the ink was to grind a mixture of hide glue, carbon black , lampblack, and bone black pigment with

3886-426: The restructuring of state finances under Yaqub ibn Killis could be embarked upon. Al-Mu'izz was succeeded by his son Al-Aziz (975–996). Al-Mu'izz was renowned for his tolerance of other religions, and was popular among his Jewish and Christian subjects. He is also credited for having commissioned the invention of the first fountain pen , when in 953, he demanded a pen which would not stain his hands or clothes, and

3953-1043: The same molecule) and solvate positively charged species via their negative dipole. In chemical reactions the use of polar protic solvents favors the S N 1 reaction mechanism , while polar aprotic solvents favor the S N 2 reaction mechanism. These polar solvents are capable of forming hydrogen bonds with water to dissolve in water whereas non-polar solvents are not capable of strong hydrogen bonds. The solvents are grouped into nonpolar , polar aprotic , and polar protic solvents, with each group ordered by increasing polarity. The properties of solvents which exceed those of water are bolded. CH 3 CH 2 CH 2 CH 2 CH 3 CH 3 CH 2 CH 2 CH 2 CH 2 CH 3 H 3 C(CH 2 ) 5 CH 3 C 6 H 5 -CH 3 CH 3 CH 2 -O-CH 2 CH 3 CHCl 3 CH 2 Cl 2 CH 3 -C≡N CH 3 -NO 2 C 4 H 6 O 3 NH 3 (at -33.3 °C) CH 3 CH 2 CH 2 CH 2 OH CH 3 CH 2 CH 2 OH CH 3 CH 2 OH CH 3 OH The ACS Green Chemistry Institute maintains

4020-544: The solvent soaks into the paper. Cellulose , the wood-derived material most paper is made of, is naturally charged, and so a compound that complexes with both the dye and the paper's surface aids retention at the surface. Such a compound is commonly used in ink-jet printing inks. An additional advantage of dye-based ink systems is that the dye molecules can interact with other ink ingredients, potentially allowing greater benefit as compared to pigmented inks from optical brighteners and color-enhancing agents designed to increase

4087-399: The solvent's tendency to partly cancel the field strength of the electric field of a charged particle immersed in it. This reduction is then compared to the field strength of the charged particle in a vacuum. Heuristically, the dielectric constant of a solvent can be thought of as its ability to reduce the solute's effective internal charge . Generally, the dielectric constant of a solvent

SECTION 60

#1732772104948

4154-436: The speed of evaporation. Small amounts of low-boiling-point solvents like diethyl ether , dichloromethane , or acetone will evaporate in seconds at room temperature, while high-boiling-point solvents like water or dimethyl sulfoxide need higher temperatures, an air flow, or the application of vacuum for fast evaporation. Most organic solvents have a lower density than water, which means they are lighter than and will form

4221-480: 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 proportions of ink ingredients, amount deposited on

4288-411: 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 pen, which may have been the first fountain pen , dates back to 953, when Ma'ād al-Mu'izz , the caliph of Egypt, demanded a pen that would not stain his hands or clothes, and was provided with a pen that held ink in

4355-728: Was first applied in the 1962 Indian general election , after being developed at the National Physical Laboratory of India . The election commission in India has used indelible ink for many elections. Indonesia used it in its election in 2014. In Mali, the ink is applied to the fingernail. Indelible ink itself is not infallible as it can be used to commit electoral fraud by marking opponent party members before they have chances to cast their votes. There are also reports of "indelible" ink washing off voters' fingers in Afghanistan. Solvent A solvent (from

4422-469: Was provided with a pen which held ink in a reservoir. As recorded by Qadi al-Nu'man al-Tamimi (d. 974) in his Kitāb al-Majālis wa 'l-musayarāt , al-Mu'izz commissioned the construction of the pen instructing: …not more than a few days passed before the craftsman, to whom the construction of this contrivance had been described, brought in the pen, fashioned from gold. He then filled it with ink and wrote with it, and it really did write. The pen released

4489-527: Was used as an ink in the Graeco-Roman period and subsequently. Black atramentum was also used in ancient Rome ; 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

#947052