In chemistry , hydrophobicity is the chemical property of a molecule that is seemingly repelled from a mass of water (called a hydrophobe ). In contrast, hydrophiles are attracted to water.
84-466: Lithography (from Ancient Greek λίθος ( líthos ) 'stone' and γράφω ( gráphō ) 'to write') is a planographic 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 the German author and actor Alois Senefelder and
168-420: A photographic process, a method that may be referred to as "photolithography" (although the term usually refers to a vaguely similar microelectronics manufacturing process ). Offset printing or "offset lithography" is an elaboration of lithography in which the ink is transferred from the plate to the paper indirectly by means of a rubber plate or cylinder, rather than by direct contact. This technique keeps
252-543: A pitch accent . In Modern Greek, all vowels and consonants are short. Many vowels and diphthongs once pronounced distinctly are pronounced as /i/ ( iotacism ). Some of the stops and glides in diphthongs have become fricatives , and the pitch accent has changed to a stress accent . Many of the changes took place in the Koine Greek period. The writing system of Modern Greek, however, does not reflect all pronunciation changes. The examples below represent Attic Greek in
336-403: A CTP ( computer-to-plate ) device known as a platesetter. The positive image is the emulsion that remains after imaging. Non-image portions of the emulsion have traditionally been removed by a chemical process, though in recent times, plates have become available that do not require such processing. The plate is affixed to a cylinder on a printing press. Dampening rollers apply water, which covers
420-426: A brushed or roughened texture and are covered with a photosensitive emulsion . A photographic negative of the desired image is placed in contact with the emulsion and the plate is exposed to ultraviolet light . After development, the emulsion shows a reverse of the negative image, which is thus a duplicate of the original (positive) image. The image on the plate emulsion can also be created by direct laser imaging in
504-633: A bulk material, through either coatings or surface treatments. That is to say, the presence of molecular species (usually organic) or structural features results in high contact angles of water. In recent years, rare earth oxides have been shown to possess intrinsic hydrophobicity. The intrinsic hydrophobicity of rare earth oxides depends on surface orientation and oxygen vacancy levels, and is naturally more robust than coatings or surface treatments, having potential applications in condensers and catalysts that can operate at high temperatures or corrosive environments. Hydrophobic concrete has been produced since
588-536: A center, and some of Géricault's prints were in fact produced there. Goya in Bordeaux produced his last series of prints by lithography— The Bulls of Bordeaux of 1828. By the mid-century the initial enthusiasm had somewhat diminished in both countries, although the use of lithography was increasingly favored for commercial applications, which included the prints of Daumier , published in newspapers. Rodolphe Bresdin and Jean-François Millet also continued to practice
672-525: A fifth major dialect group, or it is Mycenaean Greek overlaid by Doric, with a non-Greek native influence. Regarding the speech of the ancient Macedonians diverse theories have been put forward, but the epigraphic activity and the archaeological discoveries in the Greek region of Macedonia during the last decades has brought to light documents, among which the first texts written in Macedonian , such as
756-540: A gas. where θ can be measured using a contact angle goniometer . Wenzel determined that when the liquid is in intimate contact with a microstructured surface, θ will change to θ W* where r is the ratio of the actual area to the projected area. Wenzel's equation shows that microstructuring a surface amplifies the natural tendency of the surface. A hydrophobic surface (one that has an original contact angle greater than 90°) becomes more hydrophobic when microstructured – its new contact angle becomes greater than
840-453: A greasy substance, such as oil, fat, or wax onto the surface of a smooth and flat limestone plate. The stone was then treated with a mixture of weak acid and gum arabic ("etch") that made the parts of the stone's surface that were not protected by the grease more hydrophilic (water attracting). For printing, the stone was first moistened. The water adhered only to the gum-treated parts, making them even more oil-repellant. An oil-based ink
924-399: A high contact angle . Examples of hydrophobic molecules include the alkanes , oils , fats , and greasy substances in general. Hydrophobic materials are used for oil removal from water, the management of oil spills , and chemical separation processes to remove non-polar substances from polar compounds. Hydrophobic is often used interchangeably with lipophilic , "fat-loving". However,
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#17327934840331008-413: A higher entropic state which causes non-polar molecules to clump together to reduce the surface area exposed to water and decrease the entropy of the system. Thus, the two immiscible phases (hydrophilic vs. hydrophobic) will change so that their corresponding interfacial area will be minimal. This effect can be visualized in the phenomenon called phase separation. Superhydrophobic surfaces, such as
1092-452: A plate is 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. Lithography uses simple chemical processes to create an image. For instance, the positive part of an image is a water-repelling (" hydrophobic ") substance, while the negative image would be water-retaining ("hydrophilic"). Thus, when
1176-550: A prefix /e-/, called the augment . This was probably originally a separate word, meaning something like "then", added because tenses in PIE had primarily aspectual meaning. The augment is added to the indicative of the aorist, imperfect, and pluperfect, but not to any of the other forms of the aorist (no other forms of the imperfect and pluperfect exist). The two kinds of augment in Greek are syllabic and quantitative. The syllabic augment
1260-520: A rubber blanket , which squeezes away the water, picks up the ink and transfers it to the paper with uniform pressure. The paper passes between the blanket cylinder and a counter-pressure or impression cylinder and the image is transferred to the paper. Because the image is first transferred, or offset to the rubber blanket cylinder, this reproduction method is known as offset lithography or offset printing . Many innovations and technical refinements have been made in printing processes and presses over
1344-542: A strong Northwest Greek influence, and can in some respects be considered a transitional dialect, as exemplified in the poems of the Boeotian poet Pindar who wrote in Doric with a small Aeolic admixture. Thessalian likewise had come under Northwest Greek influence, though to a lesser degree. Pamphylian Greek , spoken in a small area on the southwestern coast of Anatolia and little preserved in inscriptions, may be either
1428-681: A surface having micrometer-sized features or particles ≤ 100 micrometers. The larger particles were observed to protect the smaller particles from mechanical abrasion. In recent research, superhydrophobicity has been reported by allowing alkylketene dimer (AKD) to solidify into a nanostructured fractal surface. Many papers have since presented fabrication methods for producing superhydrophobic surfaces including particle deposition, sol-gel techniques, plasma treatments, vapor deposition, and casting techniques. Current opportunity for research impact lies mainly in fundamental research and practical manufacturing. Debates have recently emerged concerning
1512-586: A surface is easily washed away. Patterned superhydrophobic surfaces also have promise for lab-on-a-chip microfluidic devices and can drastically improve surface-based bioanalysis. In pharmaceuticals, hydrophobicity of pharmaceutical blends affects important quality attributes of final products, such as drug dissolution and hardness . Methods have been developed to measure the hydrophobicity of pharmaceutical materials. The development of hydrophobic passive daytime radiative cooling (PDRC) surfaces, whose effectiveness at solar reflectance and thermal emittance
1596-510: A vowel or /n s r/ ; final stops were lost, as in γάλα "milk", compared with γάλακτος "of milk" (genitive). Ancient Greek of the classical period also differed in both the inventory and distribution of original PIE phonemes due to numerous sound changes, notably the following: The pronunciation of Ancient Greek was very different from that of Modern Greek . Ancient Greek had long and short vowels ; many diphthongs ; double and single consonants; voiced, voiceless, and aspirated stops ; and
1680-410: Is a phenomenon that characterizes surface heterogeneity. When a pipette injects a liquid onto a solid, the liquid will form some contact angle. As the pipette injects more liquid, the droplet will increase in volume, the contact angle will increase, but its three-phase boundary will remain stationary until it suddenly advances outward. The contact angle the droplet had immediately before advancing outward
1764-418: Is added to stems beginning with consonants, and simply prefixes e (stems beginning with r , however, add er ). The quantitative augment is added to stems beginning with vowels, and involves lengthening the vowel: Some verbs augment irregularly; the most common variation is e → ei . The irregularity can be explained diachronically by the loss of s between vowels, or that of the letter w , which affected
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#17327934840331848-514: Is also called an ink pyramid because the ink is transferred through several layers of rollers with different purposes. Fast lithographic 'web' printing presses are commonly used in newspaper production. The advent of desktop publishing made it possible for type and images to be modified easily on personal computers for eventual printing by desktop or commercial presses. The development of digital imagesetters enabled print shops to produce negatives for platemaking directly from digital input, skipping
1932-399: Is based on this principle. Inspired by it , many functional superhydrophobic surfaces have been prepared. An example of a bionic or biomimetic superhydrophobic material in nanotechnology is nanopin film . One study presents a vanadium pentoxide surface that switches reversibly between superhydrophobicity and superhydrophilicity under the influence of UV radiation. According to
2016-448: Is considered by some linguists to have been closely related to Greek . Among Indo-European branches with living descendants, Greek is often argued to have the closest genetic ties with Armenian (see also Graeco-Armenian ) and Indo-Iranian languages (see Graeco-Aryan ). Ancient Greek differs from Proto-Indo-European (PIE) and other Indo-European languages in certain ways. In phonotactics , ancient Greek words could end only in
2100-434: Is mostly an entropic effect originating from the disruption of the highly dynamic hydrogen bonds between molecules of liquid water by the nonpolar solute, causing the water to form a clathrate -like structure around the non-polar molecules. This structure formed is more highly ordered than free water molecules due to the water molecules arranging themselves to interact as much as possible with themselves, and thus results in
2184-415: Is still used on older presses, using rollers covered with molleton (cloth) that absorbs the water. This increased control of the water flow to the plate and allowed for better ink and water balance. Recent dampening systems include a "delta effect or vario", which slows the roller in contact with the plate, thus creating a sweeping movement over the ink image to clean impurities known as "hickies". This press
2268-403: Is termed contact angle hysteresis and can be used to characterize surface heterogeneity, roughness, and mobility. Surfaces that are not homogeneous will have domains that impede motion of the contact line. The slide angle is another dynamic measure of hydrophobicity and is measured by depositing a droplet on a surface and tilting the surface until the droplet begins to slide. In general, liquids in
2352-452: Is termed the advancing contact angle. The receding contact angle is now measured by pumping the liquid back out of the droplet. The droplet will decrease in volume, the contact angle will decrease, but its three-phase boundary will remain stationary until it suddenly recedes inward. The contact angle the droplet had immediately before receding inward is termed the receding contact angle. The difference between advancing and receding contact angles
2436-679: The Archaic or Epic period ( c. 800–500 BC ), and the Classical period ( c. 500–300 BC ). Ancient Greek was the language of Homer and of fifth-century Athenian historians, playwrights, and philosophers . It has contributed many words to English vocabulary and has been a standard subject of study in educational institutions of the Western world since the Renaissance . This article primarily contains information about
2520-606: The Epic and Classical periods of the language, which are the best-attested periods and considered most typical of Ancient Greek. From the Hellenistic period ( c. 300 BC ), Ancient Greek was followed by Koine Greek , which is regarded as a separate historical stage, though its earliest form closely resembles Attic Greek , and its latest form approaches Medieval Greek . There were several regional dialects of Ancient Greek; Attic Greek developed into Koine. Ancient Greek
2604-501: The Pella curse tablet , as Hatzopoulos and other scholars note. Based on the conclusions drawn by several studies and findings such as Pella curse tablet , Emilio Crespo and other scholars suggest that ancient Macedonian was a Northwest Doric dialect , which shares isoglosses with its neighboring Thessalian dialects spoken in northeastern Thessaly . Some have also suggested an Aeolic Greek classification. The Lesbian dialect
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2688-603: The epic poems , the Iliad and the Odyssey , and in later poems by other authors. Homeric Greek had significant differences in grammar and pronunciation from Classical Attic and other Classical-era dialects. The origins, early form and development of the Hellenic language family are not well understood because of a lack of contemporaneous evidence. Several theories exist about what Hellenic dialect groups may have existed between
2772-501: The present , future , and imperfect are imperfective in aspect; the aorist , present perfect , pluperfect and future perfect are perfective in aspect. Most tenses display all four moods and three voices, although there is no future subjunctive or imperative. Also, there is no imperfect subjunctive, optative or imperative. The infinitives and participles correspond to the finite combinations of tense, aspect, and voice. The indicative of past tenses adds (conceptually, at least)
2856-1031: The 5th century BC. Ancient pronunciation cannot be reconstructed with certainty, but Greek from the period is well documented, and there is little disagreement among linguists as to the general nature of the sounds that the letters represent. /oː/ raised to [uː] , probably by the 4th century BC. Greek, like all of the older Indo-European languages , is highly inflected. It is highly archaic in its preservation of Proto-Indo-European forms. In ancient Greek, nouns (including proper nouns) have five cases ( nominative , genitive , dative , accusative , and vocative ), three genders ( masculine , feminine , and neuter ), and three numbers (singular, dual , and plural ). Verbs have four moods ( indicative , imperative , subjunctive , and optative ) and three voices (active, middle, and passive ), as well as three persons (first, second, and third) and various other forms. Verbs are conjugated through seven combinations of tenses and aspect (generally simply called "tenses"):
2940-495: The Archaic period of ancient Greek (see Homeric Greek for more details): Μῆνιν ἄειδε, θεά, Πηληϊάδεω Ἀχιλῆος οὐλομένην, ἣ μυρί' Ἀχαιοῖς ἄλγε' ἔθηκε, πολλὰς δ' ἰφθίμους ψυχὰς Ἄϊδι προΐαψεν ἡρώων, αὐτοὺς δὲ ἑλώρια τεῦχε κύνεσσιν οἰωνοῖσί τε πᾶσι· Διὸς δ' ἐτελείετο βουλή· ἐξ οὗ δὴ τὰ πρῶτα διαστήτην ἐρίσαντε Ἀτρεΐδης τε ἄναξ ἀνδρῶν καὶ δῖος Ἀχιλλεύς. The beginning of Apology by Plato exemplifies Attic Greek from
3024-552: The Cassie–Baxter state exhibit lower slide angles and contact angle hysteresis than those in the Wenzel state. Dettre and Johnson discovered in 1964 that the superhydrophobic lotus effect phenomenon was related to rough hydrophobic surfaces, and they developed a theoretical model based on experiments with glass beads coated with paraffin or TFE telomer. The self-cleaning property of superhydrophobic micro- nanostructured surfaces
3108-399: The Cassie–Baxter state is more mobile than in the Wenzel state. We can predict whether the Wenzel or Cassie–Baxter state should exist by calculating the new contact angle with both equations. By a minimization of free energy argument, the relation that predicted the smaller new contact angle is the state most likely to exist. Stated in mathematical terms, for the Cassie–Baxter state to exist,
3192-803: The Classical period of ancient Greek. (The second line is the IPA , the third is transliterated into the Latin alphabet using a modern version of the Erasmian scheme .) Ὅτι [hóti Hóti μὲν men mèn ὑμεῖς, hyːmêːs hūmeîs, Hydrophobe Hydrophobic molecules tend to be nonpolar and, thus, prefer other neutral molecules and nonpolar solvents . Because water molecules are polar, hydrophobes do not dissolve well among them. Hydrophobic molecules in water often cluster together, forming micelles . Water on hydrophobic surfaces will exhibit
3276-545: The Dorians. The Greeks of this period believed there were three major divisions of all Greek people – Dorians, Aeolians, and Ionians (including Athenians), each with their own defining and distinctive dialects. Allowing for their oversight of Arcadian, an obscure mountain dialect, and Cypriot, far from the center of Greek scholarship, this division of people and language is quite similar to the results of modern archaeological-linguistic investigation. One standard formulation for
3360-550: The aorist. Following Homer 's practice, the augment is sometimes not made in poetry , especially epic poetry. The augment sometimes substitutes for reduplication; see below. Almost all forms of the perfect, pluperfect, and future perfect reduplicate the initial syllable of the verb stem. (A few irregular forms of perfect do not reduplicate, whereas a handful of irregular aorists reduplicate.) The three types of reduplication are: Irregular duplication can be understood diachronically. For example, lambanō (root lab ) has
3444-416: The applicability of the Wenzel and Cassie–Baxter models. In an experiment designed to challenge the surface energy perspective of the Wenzel and Cassie–Baxter model and promote a contact line perspective, water drops were placed on a smooth hydrophobic spot in a rough hydrophobic field, a rough hydrophobic spot in a smooth hydrophobic field, and a hydrophilic spot in a hydrophobic field. Experiments showed that
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3528-475: The artist. The serilith technique is used primarily to create fine art limited print editions. Ancient Greek language Ancient Greek ( Ἑλληνῐκή , Hellēnikḗ ; [hellɛːnikɛ́ː] ) includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek ( c. 1400–1200 BC ), Dark Ages ( c. 1200–800 BC ),
3612-511: The artists' work. Grant Wood , George Bellows , Alphonse Mucha , Max Kahn , Pablo Picasso , Eleanor Coen , Jasper Johns , David Hockney , Susan Dorothea White , and Robert Rauschenberg are a few of the artists who have produced most of their prints in the medium. M. C. Escher is considered a master of lithography, and many of his prints were created using this process. More than other printmaking techniques, printmakers in lithography still largely depend on access to good printers , and
3696-419: The augment when it was word-initial. In verbs with a preposition as a prefix, the augment is placed not at the start of the word, but between the preposition and the original verb. For example, προσ(-)βάλλω (I attack) goes to προσ έ βαλoν in the aorist. However compound verbs consisting of a prefix that is not a preposition retain the augment at the start of the word: αὐτο(-)μολῶ goes to ηὐ τομόλησα in
3780-402: The blank portions of the plate but is repelled by the emulsion of the image area. Hydrophobic ink, which is repelled by the water and only adheres to the emulsion of the image area, is then applied by the inking rollers. If this image were transferred directly to paper, it would create a mirror-type image and the paper would become too wet. Instead, the plate rolls against a cylinder covered with
3864-660: The development of the medium has been greatly influenced by when and where these have been established. An American scene for lithography was founded by Robert Blackburn in New York City. As a special form of lithography, the serilith or seriolithograph process is sometimes used. Seriliths are mixed-media original prints created in a process in which an artist uses the lithograph and serigraph (screen printing). Fine art prints of this type are published by artists and publishers worldwide, and are widely accepted and collected. The separations for both processes are hand-drawn by
3948-615: The dialect of Sparta ), and Northern Peloponnesus Doric (including Corinthian ). All the groups were represented by colonies beyond Greece proper as well, and these colonies generally developed local characteristics, often under the influence of settlers or neighbors speaking different Greek dialects. After the conquests of Alexander the Great in the late 4th century BC, a new international dialect known as Koine or Common Greek developed, largely based on Attic Greek , but with influence from other dialects. This dialect slowly replaced most of
4032-530: The dialects is: West vs. non-West Greek is the strongest-marked and earliest division, with non-West in subsets of Ionic-Attic (or Attic-Ionic) and Aeolic vs. Arcadocypriot, or Aeolic and Arcado-Cypriot vs. Ionic-Attic. Often non-West is called 'East Greek'. Arcadocypriot apparently descended more closely from the Mycenaean Greek of the Bronze Age. Boeotian Greek had come under
4116-510: The divergence of early Greek-like speech from the common Proto-Indo-European language and the Classical period. They have the same general outline but differ in some of the detail. The only attested dialect from this period is Mycenaean Greek , but its relationship to the historical dialects and the historical circumstances of the times imply that the overall groups already existed in some form. Scholars assume that major Ancient Greek period dialect groups developed not later than 1120 BC, at
4200-467: The early days of lithography, a smooth piece of limestone was used (hence the name "lithography": "lithos" ( λιθος ) is the Ancient Greek word for "stone"). After the oil-based image was put on the surface, a solution of gum arabic in water was applied, the gum sticking only to the non-oily surface. During printing, water adhered to the gum arabic surfaces and was repelled by the oily parts, while
4284-402: The electrons reduce V to V . The oxygen vacancies are met by water, and it is this water absorbency by the vanadium surface that makes it hydrophilic. By extended storage in the dark, water is replaced by oxygen and hydrophilicity is once again lost. A significant majority of hydrophobic surfaces have their hydrophobic properties imparted by structural or chemical modification of a surface of
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#17327934840334368-420: The following inequality must be true. A recent alternative criterion for the Cassie–Baxter state asserts that the Cassie–Baxter state exists when the following 2 criteria are met:1) Contact line forces overcome body forces of unsupported droplet weight and 2) The microstructures are tall enough to prevent the liquid that bridges microstructures from touching the base of the microstructures. A new criterion for
4452-449: The intermediate step of photographing an actual page layout. The development of the digital platesetter during the late 20th century eliminated film negatives altogether by exposing printing plates directly from digital input, a process known as computer-to-plate printing. During the early years of the 19th century, lithography had only a limited effect on printmaking , mainly because technical difficulties remained to be overcome. Germany
4536-425: The leaves of the lotus plant, are those that are extremely difficult to wet. The contact angles of a water droplet exceeds 150°. This is referred to as the lotus effect , and is primarily a chemical property related to interfacial tension , rather than a chemical property. In 1805, Thomas Young defined the contact angle θ by analyzing the forces acting on a fluid droplet resting on a solid surface surrounded by
4620-411: The material being used, and its ability to withstand water and acid. After the drawing of the image, an aqueous solution of gum arabic , weakly acidified with nitric acid ( HNO 3 ) is applied to the stone. The function of this solution is to create a hydrophilic layer of calcium nitrate salt, Ca(NO 3 ) 2 , and gum arabic on all non-image surfaces. The gum solution penetrates into
4704-546: The medium in France, and Adolph Menzel in Germany. In 1862 the publisher Cadart tried to initiate a portfolio of lithographs by various artists, which was not successful but included several prints by Manet . The revival began during the 1870s, especially in France with artists such as Odilon Redon , Henri Fantin-Latour and Degas producing much of their work in this manner. The need for strictly limited editions to maintain
4788-458: The mid-20th century. Active recent research on superhydrophobic materials might eventually lead to more industrial applications. A simple routine of coating cotton fabric with silica or titania particles by sol-gel technique has been reported, which protects the fabric from UV light and makes it superhydrophobic. An efficient routine has been reported for making polyethylene superhydrophobic and thus self-cleaning. 99% of dirt on such
4872-419: The oily ink used for printing did the opposite. Lithography works because of the mutual repulsion of oil and water . The image is drawn on the surface of the print plate with a fat or oil-based medium (hydrophobic) such as a wax crayon , which may be pigmented to make the drawing visible. A wide range of oil-based media is available, but the durability of the image on the stone depends on the lipid content of
4956-508: The older dialects, although the Doric dialect has survived in the Tsakonian language , which is spoken in the region of modern Sparta. Doric has also passed down its aorist terminations into most verbs of Demotic Greek . By about the 6th century AD, the Koine had slowly metamorphosed into Medieval Greek . Phrygian is an extinct Indo-European language of West and Central Anatolia , which
5040-408: The original. However, a hydrophilic surface (one that has an original contact angle less than 90°) becomes more hydrophilic when microstructured – its new contact angle becomes less than the original. Cassie and Baxter found that if the liquid is suspended on the tops of microstructures, θ will change to θ CB* : where φ is the area fraction of the solid that touches the liquid. Liquid in
5124-407: The paper dry and allows fully automated high-speed operation. It has mostly replaced traditional lithography for medium- and high-volume printing: since the 1960s, most books and magazines, especially when illustrated in colour, are printed with offset lithography from photographically created metal plates. As a printing technology, lithography is different from intaglio printing (gravure), wherein
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#17327934840335208-487: The perfect stem eilēpha (not * lelēpha ) because it was originally slambanō , with perfect seslēpha , becoming eilēpha through compensatory lengthening. Reduplication is also visible in the present tense stems of certain verbs. These stems add a syllable consisting of the root's initial consonant followed by i . A nasal stop appears after the reduplication in some verbs. The earliest extant examples of ancient Greek writing ( c. 1450 BC ) are in
5292-489: The plate is introduced to a compatible printing ink and water mixture, the ink will adhere to the positive image and the water will clean the negative image. This allows a flat print plate to be used, enabling much longer and more detailed print runs than the older physical methods of printing (e.g., intaglio printing, letterpress printing). Lithography was invented by Alois Senefelder in the Kingdom of Bavaria in 1796. In
5376-408: The pores of the stone, completely surrounding the original image with a hydrophilic layer that will not accept the printing ink. Using lithographic turpentine , the printer then removes any excess of the greasy drawing material, but a hydrophobic molecular film of it remains tightly bonded to the surface of the stone, rejecting the gum arabic and water, but ready to accept the oily ink. When printing,
5460-416: The price had now been realized, and the medium became more accepted. In the 1890s, color lithography gained success in part by the emergence of Jules Chéret , known as the father of the modern poster , whose work went on to inspire a new generation of poster designers and painters, most notably Toulouse-Lautrec , and former student of Chéret, Georges de Feure . By 1900 the medium in both color and monotone
5544-496: The printing of wallpaper; but it was transformed when the founder's grandson, Fernand Mourlot , invited a number of 20th-century artists to explore the complexities of fine art printing. Mourlot encouraged the painters to work directly on lithographic stones in order to create original artworks that could then be executed under the direction of master printers in small editions. The combination of modern artist and master printer resulted in lithographs that were used as posters to promote
5628-492: The stone and paper are run through a press that applies even pressure over the surface, transferring the ink to the paper and off the stone. Senefelder had experimented during the early 19th century with multicolor lithography; in his 1819 book, he predicted that the process would eventually be perfected and used to reproduce paintings. Multi-color printing was introduced by a new process developed by Godefroy Engelmann (France) in 1837 known as chromolithography . A separate stone
5712-404: The stone is kept wet with water. The water is naturally attracted to the layer of gum and salt created by the acid wash. Printing ink based on drying oils such as linseed oil and varnish loaded with pigment is then rolled over the surface. The water repels the greasy ink but the hydrophobic areas left by the original drawing material accept it. When the hydrophobic image is loaded with ink,
5796-421: The study, any surface can be modified to this effect by application of a suspension of rose-like V 2 O 5 particles, for instance with an inkjet printer . Once again hydrophobicity is induced by interlaminar air pockets (separated by 2.1 nm distances). The UV effect is also explained. UV light creates electron-hole pairs , with the holes reacting with lattice oxygen, creating surface oxygen vacancies, while
5880-437: The surface chemistry and geometry at the contact line affected the contact angle and contact angle hysteresis , but the surface area inside the contact line had no effect. An argument that increased jaggedness in the contact line enhances droplet mobility has also been proposed. Many hydrophobic materials found in nature rely on Cassie's law and are biphasic on the submicrometer level with one component air. The lotus effect
5964-509: The switch between Wenzel and Cassie-Baxter states has been developed recently based on surface roughness and surface energy . The criterion focuses on the air-trapping capability under liquid droplets on rough surfaces, which could tell whether Wenzel's model or Cassie-Baxter's model should be used for certain combination of surface roughness and energy. Contact angle is a measure of static hydrophobicity, and contact angle hysteresis and slide angle are dynamic measures. Contact angle hysteresis
6048-517: The syllabic script Linear B . Beginning in the 8th century BC, however, the Greek alphabet became standard, albeit with some variation among dialects. Early texts are written in boustrophedon style, but left-to-right became standard during the classic period. Modern editions of ancient Greek texts are usually written with accents and breathing marks , interword spacing , modern punctuation , and sometimes mixed case , but these were all introduced later. The beginning of Homer 's Iliad exemplifies
6132-467: The time of the Dorian invasions —and that their first appearances as precise alphabetic writing began in the 8th century BC. The invasion would not be "Dorian" unless the invaders had some cultural relationship to the historical Dorians . The invasion is known to have displaced population to the later Attic-Ionic regions, who regarded themselves as descendants of the population displaced by or contending with
6216-432: The two terms are not synonymous. While hydrophobic substances are usually lipophilic, there are exceptions, such as the silicones and fluorocarbons . The term hydrophobe comes from the Ancient Greek ὑδρόφοβος ( hydróphobos ), "having a fear of water", constructed from Ancient Greek ὕδωρ (húdōr) 'water' and Ancient Greek φόβος (phóbos) 'fear'. The hydrophobic interaction
6300-409: The years, including the development of presses with multiple units (each containing one printing plate) that can print multi-color images in one pass on both sides of the sheet, and presses that accommodate continuous rolls ( webs ) of paper, known as web presses. Another innovation was the continuous dampening system first introduced by Dahlgren, instead of the old method (conventional dampening) which
6384-480: Was Aeolic. For example, fragments of the works of the poet Sappho from the island of Lesbos are in Aeolian. Most of the dialect sub-groups listed above had further subdivisions, generally equivalent to a city-state and its surrounding territory, or to an island. Doric notably had several intermediate divisions as well, into Island Doric (including Cretan Doric ), Southern Peloponnesus Doric (including Laconian ,
6468-452: Was a pluricentric language , divided into many dialects. The main dialect groups are Attic and Ionic , Aeolic , Arcadocypriot , and Doric , many of them with several subdivisions. Some dialects are found in standardized literary forms in literature , while others are attested only in inscriptions. There are also several historical forms. Homeric Greek is a literary form of Archaic Greek (derived primarily from Ionic and Aeolic) used in
6552-742: Was a quick, cheap process and had been used to print British army maps during the Peninsular War . Most of the commercial maps of the second half of the 19th century were lithographed and unattractive, though accurate enough." High-volume lithography is used to produce posters, maps, books, newspapers, and packaging—just about any smooth, mass-produced item with print and graphics on it. Most books, indeed all types of high-volume text, are printed using offset lithography. For offset lithography, which depends on photographic processes, flexible aluminum , polyester , mylar or paper printing plates are used instead of stone tablets. Modern printing plates have
6636-526: Was an accepted part of printmaking. During the 20th century, a group of artists, including Braque , Calder , Chagall , Dufy , Léger , Matisse , Miró , and Picasso , rediscovered the largely undeveloped artform of lithography thanks to the Mourlot Studios , also known as Atelier Mourlot , a Parisian printshop founded in 1852 by the Mourlot family. The Atelier Mourlot originally specialized in
6720-405: Was initially used mostly for musical scores and maps. Lithography can be used to print text or images onto paper or other suitable material. A lithograph is something printed by lithography, but this term is only used for fine art prints and some other, mostly older, types of printed matter, not for those made by modern commercial lithography. Originally, the image to be printed was drawn with
6804-457: Was reported in 1977. Perfluoroalkyl, perfluoropolyether, and RF plasma -formed superhydrophobic materials were developed, used for electrowetting and commercialized for bio-medical applications between 1986 and 1995. Other technology and applications have emerged since the mid-1990s. A durable superhydrophobic hierarchical composition, applied in one or two steps, was disclosed in 2002 comprising nano-sized particles ≤ 100 nanometers overlaying
6888-669: Was the main center of production in this period. Godefroy Engelmann , who moved his press from Mulhouse to Paris in 1816, largely succeeded in resolving the technical problems, and during the 1820s lithography was adopted by artists such as Delacroix and Géricault . After early experiments such as Specimens of Polyautography (1803), which had experimental works by a number of British artists including Benjamin West , Henry Fuseli , James Barry , Thomas Barker of Bath , Thomas Stothard , Henry Richard Greville , Richard Cooper , Henry Singleton , and William Henry Pyne , London also became
6972-440: Was then applied, and would stick only to the original drawing. The ink would finally be transferred to a blank sheet of paper , producing a printed page. This traditional technique is still used for fine art printmaking. In modern commercial lithography, the image is transferred or created as a patterned polymer coating applied to a flexible plastic or metal plate. The printing plates, made of stone or metal, can be created by
7056-443: Was used for each color, and a print went through the press separately for each stone. The main challenge was to keep the images aligned ( in register ). This method lent itself to images consisting of large areas of flat color, and resulted in the characteristic poster designs of this period. "Lithography, or printing from soft stone, largely took the place of engraving in the production of English commercial maps after about 1852. It
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