Ink is a liquid or paste that contains pigments or dyes and is used to color a surface to produce an image, text, or design. Ink is used for drawing or writing with a pen, brush, or quill. Thicker inks, in paste form, are used extensively in letterpress and lithographic printing.
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.
In 2011 worldwide consumption of printing inks generated revenues of more than 20 billion US dollars. Demand by traditional print media is shrinking, on the other hand more and more printing inks are consumed for packagings.
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 to the 23rd 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 from soot and animal glue. The best inks for drawing or painting on paper or silk are produced from the resin of the pine tree. They must be 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.
The process of making India ink was known in China as early as the middle of the 3rd millennium BC, during Neolithic China. India ink was first invented in China, although the source of materials to make the carbon pigment in India ink was later often traded from India, thus the term India ink was coined. The traditional Chinese method of making the ink was to grind a mixture of hide glue, carbon black, lampblack, and bone black pigment with a pestle and mortar, then pouring it into a ceramic dish where it could 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 Chinese Turkestan. 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.
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 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 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 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:
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.
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, making the ink less efficient and 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 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 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 the intensity and appearance of dyes.
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.
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 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 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 have 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 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 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 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 the paper, and paper composition (Barrow 1972:16). Corrosion is caused by acid catalysed 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 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 phytate. 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 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 a catalyst to cellulose oxidation. These chemical reactions physically weaken the paper, causing brittleness.
Indelible means "unremovable". 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. The Indian Scientist Dr. M.L. Goel is the founding father of indelible ink in India and gave the secret formula to NPL (National Physical Laboratory) of India.
The Election Commission in India has used indelible ink for many elections. Indonesia used it in its last election in Aceh. 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.
A ballpoint pen, also known as a biro or ball pen, is a pen that dispenses ink (usually in paste form) over a metal ball at its point, i.e. over a "ball point". The metal commonly used is steel, brass, or tungsten carbide. It was conceived and developed as a cleaner and more reliable alternative to dip pens and fountain pens, and it is now the world's most-used writing instrument: millions are manufactured and sold daily. As a result, it has influenced art and graphic design and spawned an artwork genre.
Pen manufacturers produce designer ballpoint pens for the high-end and collectors' markets.
The Bic Cristal is a popular disposable type of ballpoint pen whose design is recognised by its place in the permanent collection of the Museum of Modern Art, New York.Black
Black is the darkest color, the result of the absence or complete absorption of visible light. It is an achromatic color, literally a color without hue, like white and gray. It is often used symbolically or figuratively to represent darkness, while white represents light. Black and white have often been used to describe opposites; particularly truth and ignorance, good and evil, the Dark Ages versus Age of Enlightenment. Since the Middle Ages, black has been the symbolic color of solemnity and authority, and for this reason is still commonly worn by judges and magistrates.Black was one of the first colors used by artists in neolithic cave paintings. In the 14th century, it was worn by royalty, clergy, judges and government officials in much of Europe. It became the color worn by English romantic poets, businessmen and statesmen in the 19th century, and a high fashion color in the 20th century. In the Roman Empire, it became the color of mourning, and over the centuries it was frequently associated with death, evil, witches and magic. According to surveys in Europe and North America, it is the color most commonly associated with mourning, the end, secrets, magic, force, violence, evil, and elegance.Black ink is the most common color used for printing books, newspapers and documents, as provides the highest contrast with white paper and thus the easiest color to read. Similarly, black text on a white screen is the most common format used on computer screens.CMYK color model
The CMYK color model (process color, four color) is a subtractive color model, used in color printing, and is also used to describe the printing process itself. CMYK refers to the four inks used in some color printing: cyan, magenta, yellow, and key.
The CMYK model works by partially or entirely masking colors on a lighter, usually white, background. The ink reduces the light that would otherwise be reflected. Such a model is called subtractive because inks "subtract" the colors red, green and blue from white light. White light minus red leaves cyan, white light minus green leaves magenta, and white light minus blue leaves yellow.
In additive color models, such as RGB, white is the "additive" combination of all primary colored lights, while black is the absence of light. In the CMYK model, it is the opposite: white is the natural color of the paper or other background, while black results from a full combination of colored inks. To save cost on ink, and to produce deeper black tones, unsaturated and dark colors are produced by using black ink instead of the combination of cyan, magenta, and yellow.Chinese painting
Chinese painting is one of the oldest continuous artistic traditions in the world. Painting in the traditional style is known today in Chinese as guóhuà (simplified Chinese: 国画; traditional Chinese: 國畫), meaning "national" or "native painting", as opposed to Western styles of art which became popular in China in the 20th century. Traditional painting involves essentially the same techniques as calligraphy and is done with a brush dipped in black ink or coloured pigments; oils are not used. As with calligraphy, the most popular materials on which paintings are made are paper and silk. The finished work can be mounted on scrolls, such as hanging scrolls or handscrolls. Traditional painting can also be done on album sheets, walls, lacquerware, folding screens, and other media.
The two main techniques in Chinese painting are:
Gongbi (工筆), meaning "meticulous", uses highly detailed brushstrokes that delimit details very precisely. It is often highly coloured and usually depicts figural or narrative subjects. It is often practised by artists working for the royal court or in independent workshops.
Ink and wash painting, in Chinese shui-mo (水墨, "water and ink") also loosely termed watercolour or brush painting, and also known as "literati painting", as it was one of the "Four Arts" of the Chinese Scholar-official class. In theory this was an art practiced by gentlemen, a distinction that begins to be made in writings on art from the Song dynasty, though in fact the careers of leading exponents could benefit considerably. This style is also referred to as "xieyi" (寫意) or freehand style.Landscape painting was regarded as the highest form of Chinese painting, and generally still is. The time from the Five Dynasties period to the Northern Song period (907–1127) is known as the "Great age of Chinese landscape". In the north, artists such as Jing Hao, Li Cheng, Fan Kuan, and Guo Xi painted pictures of towering mountains, using strong black lines, ink wash, and sharp, dotted brushstrokes to suggest rough stone. In the south, Dong Yuan, Juran, and other artists painted the rolling hills and rivers of their native countryside in peaceful scenes done with softer, rubbed brushwork. These two kinds of scenes and techniques became the classical styles of Chinese landscape painting.Electronic paper
Electronic paper and e-paper, also sometimes electronic ink or e-ink, are display devices that mimic the appearance of ordinary ink on paper. Unlike conventional backlit flat panel displays that emit light, electronic paper displays reflect light like paper. This may make them more comfortable to read, and provide a wider viewing angle than most light-emitting displays. The contrast ratio in electronic displays available as of 2008 approaches newspaper, and newly (2008) developed displays are slightly better. An ideal e-paper display can be read in direct sunlight without the image appearing to fade.
Many electronic paper technologies hold static text and images indefinitely without electricity. Flexible electronic paper uses plastic substrates and plastic electronics for the display backplane. There is ongoing competition among manufacturers to provide full-color ability.
Applications of electronic visual displays include electronic pricing labels in retail shops and digital signage, time tables at bus stations, electronic billboards, smartphone displays, and e-readers able to display digital versions of books and magazines.Fountain pen
A fountain pen is a nib pen that, unlike its predecessor, the dip pen, contains an internal reservoir of liquid ink. The pen draws ink from the reservoir through a feed to the nib and deposits it on paper via a combination of gravity and capillary action. Filling the reservoir with ink may be achieved manually, via the use of a Pasteur pipette (eyedropper) or syringe, or via an internal filling mechanism which creates suction (for example, through a piston mechanism) or a vacuum to transfer ink directly through the nib into the reservoir. Some pens employ removable reservoirs in the form of pre-filled ink cartridges.India ink
India ink (British English: Indian Ink; also Chinese ink) is a simple black or colored ink once widely used for writing and printing and now more commonly used for drawing and outlining, especially when inking comic books and comic strips. India ink is also used in medical applications.Ink wash painting
Ink wash painting (Chinese: 水墨畫; pinyin: shuǐmòhuà; Japanese: 水墨画, translit. suiboku-ga; Korean: 수묵화, translit. sumukhwa), or sumi-e (墨絵), is a type of East Asian brush painting that uses black ink – as used in East Asian calligraphy – in different concentrations. Emerging in Tang dynasty China (618–907), it, and associated stylistic features, overturned earlier, more realistic techniques. These associated features include a preference for shades of black over variations in colour, and an emphasis on brushwork and the perceived "spirit" or "essence" of a subject over direct imitation. It flourished in the Song dynasty (960–1279), as well as Japan after it was introduced by Zen Buddhist monks in the 14th century.Inkjet printing
Inkjet printing is a type of computer printing that recreates a digital image by propelling droplets of ink onto paper, plastic, or other substrates. Inkjet printers are the most commonly used type of printer, and range from small inexpensive consumer models to expensive professional machines.
The concept of inkjet printing originated in the 20th century, and the technology was first extensively developed in the early 1950s. Starting in the late 1970s, inkjet printers that could reproduce digital images generated by computers were developed, mainly by Epson, Hewlett-Packard (HP) and Canon. In the worldwide consumer market, four manufacturers account for the majority of inkjet printer sales: Canon, HP, Epson and Brother.
The emerging ink jet material deposition market also uses inkjet technologies, typically printheads using piezoelectric crystals, to deposit materials directly on substrates.
The technology has been extended and the 'ink' can now also comprise solder paste in PCB assembly, or living cells, for creating biosensors and for tissue engineering.
Images produced on inkjet printers are sometime sold under other names since the term is associated with words like "digital", "computers", and "everyday printing", which can have negative connotations in some contexts. These trade names or coined terms are usually used in the fine arts reproduction field. They include Digigraph, Iris prints (or Giclée), and Cromalin.Kid Ink
Brian Todd Collins (born April 1, 1986), best known by his stage name Kid Ink, is an American rapper, singer, and record producer from Los Angeles, California. Collins released his debut independent album Up & Away in 2012, following an EP titled Almost Home, and his first major studio album, My Own Lane in 2014. The latter spawned the singles "Show Me", "Iz U Down", and "Main Chick" featuring Chris Brown. On February 3, 2015, he released his third studio album Full Speed, which spawned the singles "Body Language", "Hotel", and "Be Real" featuring Dej Loaf. On December 25, 2015, he released a surprise commercial mixtape Summer in the Winter with the supporting single "Promise" featuring Fetty Wap. Kid Ink has also released RSS2 (a mixtape) in 2016, and EP 7 Series with leading single "F with U" in 2017.Lithography
Lithography (from Ancient Greek λίθος, lithos, meaning 'stone', and γράφειν, graphein, meaning 'to write') is a method of printing originally based on the immiscibility of oil and water. The printing is from a stone (lithographic limestone) or a metal plate with a smooth surface. It was invented in 1796 by German author and actor Alois Senefelder as a cheap method of publishing theatrical works. Lithography can be used to print text or artwork onto paper or other suitable material.Lithography originally used an image drawn with oil, fat, or wax onto the surface of a smooth, level lithographic limestone plate. The stone was treated with a mixture of acid and gum arabic, etching the portions of the stone that were not protected by the grease-based image. When the stone was subsequently moistened, these etched areas retained water; an oil-based ink could then be applied and would be repelled by the water, sticking only to the original drawing. The ink would finally be transferred to a blank paper sheet, producing a printed page. This traditional technique is still used in some fine art printmaking applications.
In modern lithography, the image is made of a polymer coating applied to a flexible plastic or metal plate. The image can be printed directly from the plate (the orientation of the image is reversed), or it can be offset, by transferring the image onto a flexible sheet (rubber) for printing and publication.
As a printing technology, lithography is different from intaglio printing (gravure), wherein a plate is either engraved, etched, or stippled to score cavities to contain the printing ink; and woodblock printing or letterpress printing, wherein ink is applied to the raised surfaces of letters or images. Today, most types of high-volume books and magazines, especially when illustrated in colour, are printed with offset lithography, which has become the most common form of printing technology since the 1960s.
The related term "photolithography" refers to when photographic images are used in lithographic printing, whether these images are printed directly from a stone or from a metal plate, as in offset printing. "Photolithography" is used synonymously with "offset printing". The technique as well as the term were introduced in Europe in the 1850s. Beginning in the 1960s, photolithography has played an important role in the fabrication and mass production of integrated circuits in the microelectronics industry.Magnetic ink character recognition
MICR code is a character-recognition technology used mainly by the banking industry to ease the processing and clearance of cheques and other documents. The MICR encoding, called the MICR line, is at the bottom of cheques and other vouchers and typically includes the document-type indicator, bank code, bank account number, cheque number, cheque amount, and a control indicator. The technology allows MICR readers to scan and read the information directly into a data-collection device. Unlike barcodes and similar technologies, MICR characters can be read easily by humans. The MICR E-13B font has been adopted as the international standard in ISO 1004:1995, but the CMC-7 font is widely used in Europe, Brazil, Mexico and some other countries.Pen
A pen is a writing instrument used to apply ink to a surface, usually paper, for writing or drawing. Historically, reed pens, quill pens, and dip pens were used, with a nib dipped in ink. Ruling pens allow precise adjustment of line width, and still find a few specialized uses, but technical pens such as the Rapidograph are more commonly used. Modern types include ballpoint, rollerball, fountain and felt or ceramic tip pens.Printer (computing)
In computing, a printer is a peripheral device which makes a persistent human-readable representation of graphics or text on paper.
The first computer printer designed was a mechanically driven apparatus by Charles Babbage for his difference engine in the 19th century; however, his mechanical printer design was not built until 2000. The first electronic printer was the EP-101, invented by Japanese company Epson and released in 1968. The first commercial printers generally used mechanisms from electric typewriters and Teletype machines. The demand for higher speed led to the development of new systems specifically for computer use. In the 1980s were daisy wheel systems similar to typewriters, line printers that produced similar output but at much higher speed, and dot matrix systems that could mix text and graphics but produced relatively low-quality output. The plotter was used for those requiring high quality line art like blueprints.
The introduction of the low-cost laser printer in 1984 with the first HP LaserJet, and the addition of PostScript in next year's Apple LaserWriter, set off a revolution in printing known as desktop publishing. Laser printers using PostScript mixed text and graphics, like dot-matrix printers, but at quality levels formerly available only from commercial typesetting systems. By 1990, most simple printing tasks like fliers and brochures were now created on personal computers and then laser printed; expensive offset printing systems were being dumped as scrap. The HP Deskjet of 1988 offered the same advantages as laser printer in terms of flexibility, but produced somewhat lower quality output (depending on the paper) from much less expensive mechanisms. Inkjet systems rapidly displaced dot matrix and daisy wheel printers from the market. By the 2000s high-quality printers of this sort had fallen under the $100 price point and became commonplace.
The rapid update of internet email through the 1990s and into the 2000s has largely displaced the need for printing as a means of moving documents, and a wide variety of reliable storage systems means that a "physical backup" is of little benefit today. Even the desire for printed output for "offline reading" while on mass transit or aircraft has been displaced by e-book readers and tablet computers. Today, traditional printers are being used more for special purposes, like printing photographs or artwork, and are no longer a must-have peripheral.
Starting around 2010, 3D printing became an area of intense interest, allowing the creation of physical objects with the same sort of effort as an early laser printer required to produce a brochure. These devices are in their earliest stages of development and have not yet become commonplace.Printmaking
Printmaking is the process of creating artworks by printing, normally on paper. Printmaking normally covers only the process of creating prints that have an element of originality, rather than just being a photographic reproduction of a painting. Except in the case of monotyping, the process is capable of producing multiples of the same piece, which is called a print. Each print produced is not considered a "copy" but rather is considered an "original". This is because typically each print varies to an extent due to variables intrinsic to the printmaking process, and also because the imagery of a print is typically not simply a reproduction of another work but rather is often a unique image designed from the start to be expressed in a particular printmaking technique. A print may be known as an impression. Printmaking (other than monotyping) is not chosen only for its ability to produce multiple impressions, but rather for the unique qualities that each of the printmaking processes lends itself to.
Prints are created by transferring ink from a matrix or through a prepared screen to a sheet of paper or other material. Common types of matrices include: metal plates, usually copper or zinc, or polymer plates for engraving or etching; stone, aluminum, or polymer for lithography; blocks of wood for woodcuts and wood engravings; and linoleum for linocuts. Screens made of silk or synthetic fabrics are used for the screenprinting process. Other types of matrix substrates and related processes are discussed below.
Multiple impressions printed from the same matrix form an edition. Since the late 19th century, artists have generally signed individual impressions from an edition and often number the impressions to form a limited edition; the matrix is then destroyed so that no more prints can be produced. Prints may also be printed in book form, such as illustrated books or artist's books.Rorschach test
The Rorschach test is a psychological test in which subjects' perceptions of inkblots are recorded and then analyzed using psychological interpretation, complex algorithms, or both. Some psychologists use this test to examine a person's personality characteristics and emotional functioning. It has been employed to detect underlying thought disorder, especially in cases where patients are reluctant to describe their thinking processes openly. The test is named after its creator, Swiss psychologist Hermann Rorschach. In the 1960s, the Rorschach was the most widely used projective test.Although the Exner Scoring System (developed since the 1960s) claims to have addressed and often refuted many criticisms of the original testing system with an extensive body of research, some researchers continue to raise questions. The areas of dispute include the objectivity of testers, inter-rater reliability, the verifiability and general validity of the test, bias of the test's pathology scales towards greater numbers of responses, the limited number of psychological conditions which it accurately diagnoses, the inability to replicate the test's norms, its use in court-ordered evaluations, and the proliferation of the ten inkblot images, potentially invalidating the test for those who have been exposed to them.Screen printing
Screen printing is a printing technique whereby a mesh is used to transfer ink onto a substrate, except in areas made impermeable to the ink by a blocking stencil. A blade or squeegee is moved across the screen to fill the open mesh apertures with ink, and a reverse stroke then causes the screen to touch the substrate momentarily along a line of contact. This causes the ink to wet the substrate and be pulled out of the mesh apertures as the screen springs back after the blade has passed. One color is printed at a time, so several screens can be used to produce a multicoloured image or design.
There are various terms used for what is essentially the same technique. Traditionally the process was called screen printing or silkscreen printing because silk was used in the process. It is also known as serigraphy, and serigraph printing. Currently, synthetic threads are commonly used in the screen printing process. The most popular mesh in general use is made of polyester. There are special-use mesh materials of nylon and stainless steel available to the screen printer. There are also different types of mesh size which will determine the outcome and look of the finished design on the material.The Ink Spots
The Ink Spots were an American pop vocal group who gained international fame in the 1930s and 1940s. Their unique musical style presaged the rhythm and blues and rock and roll musical genres, and the subgenre doo-wop. The Ink Spots were widely accepted in both the white and black communities, largely due to the ballad style introduced to the group by lead singer Bill Kenny.
In 1989, the Ink Spots (Bill Kenny, Deek Watson, Charlie Fuqua and Hoppy Jones) were inducted into the Rock and Roll Hall of Fame, and in 1999 they were inducted into the Vocal Group Hall of Fame. Since the Ink Spots disbanded in 1954, there have been well over 100 vocal groups calling themselves "The Ink Spots" without any right to the name, and without any original members of the group. These groups often have claimed to be "2nd generation" or "3rd generation" Ink Spots.YG (rapper)
Keenon Daequan Ray Jackson (born March 9, 1990), better known by his stage name YG, is an American rapper and actor from Compton, California. In 2009, he released his debut single, "Toot It and Boot It" featuring Ty Dolla Sign, which peaked at number 67 on the Billboard Hot 100. The single's success resulted in him signing to Def Jam Recordings. In the following years, YG released mixtapes such as The Real 4Fingaz, Just Re'd Up, Just Re'd Up 2, 4 Hunnid Degreez, and many others.
In June 2013, YG signed a deal to Young Jeezy's imprint CTE World. His 2013 single, "My Nigga" featuring Jeezy and Rich Homie Quan, peaked at number 19 on the US Billboard Hot 100, becoming the highest charting song of his career. He then released the singles "Left, Right" and "Who Do You Love?" featuring Drake, leading up to the release of his debut studio album. His debut album, My Krazy Life, was released on March 18, 2014 by Pu$haz Ink, CTE World and Def Jam, and received critical acclaim. On June 17, 2016, he released his second studio album, Still Brazy, to critical acclaim. On August 3, 2018, he released his third studio album, Stay Dangerous, to generally positive reviews.