Hexion Inc. or Hexion (previously Momentive Specialty Chemicals ) is a chemical company based in Columbus, Ohio . It produces thermoset resins and related technologies and specialty products.
89-720: Hexion is organized into two divisions: the Epoxy, Phenolic and Coating Resins Division, and the Forest Products Division. Hexion offers resins for a wide range of applications like Abrasives, Adhesives , Chemical Intermediates, Civil Engineering , Coatings , Composites, Crop Protection, Electrical/Electronics, Engineered Wood, Fertilizers and Pesticides, Fibers and Textiles, Foams, Friction Materials, Furniture, Molding Compounds, Oilfield, Oriented Strand Board, Particleboard and Fiberboard, Plywood and Laminated Veneer Lumber and Refractories. Hexion Specialty Chemicals, Inc
178-401: A Thread-locking fluid . Multi-component adhesives harden by mixing two or more components which chemically react. This reaction causes polymers to cross-link into acrylates , urethanes , and epoxies (see Thermosetting polymer ) . There are several commercial combinations of multi-component adhesives in use in industry. Some of these combinations are: The individual components of
267-539: A casket made of wood and glue in King Tutankhamun's tomb. Other ancient Egyptian artifacts employ animal glue for bonding or lamination. Such lamination of wood for bows and furniture is thought to have extended their life and was accomplished using casein (milk protein)-based glues. The ancient Egyptians also developed starch-based pastes for the bonding of papyrus to clothing and a plaster of Paris -like material made of calcined gypsum. From AD 1 to 500
356-510: A chemical reaction with an external energy source, such as radiation , heat, and moisture . Ultraviolet (UV) light curing adhesives , also known as light curing materials (LCM), have become popular within the manufacturing sector due to their rapid curing time and strong bond strength. Light curing adhesives can cure in as little as one second and many formulations can bond dissimilar substrates (materials) and withstand harsh temperatures. These qualities make UV curing adhesives essential to
445-673: A colouring agent in Africa for over 200,000 years. Women of the Himba ethnic group in Namibia use a mix of ochre and animal fat for body decoration, to achieve a reddish skin colour. The ochre mixture is also applied to their hair after braiding. Men and women of the Maasai people in Kenya and Tanzania have also used ochre in the same way. In Ancient Egypt , yellow was associated with gold, which
534-490: A definitive agreement to sell its manufacturing site in Yumbo, Colombia to a joint venture led by Master Paints & Chemical Corporation. In February 2022, it was announced the company epoxy division acquisition by Westlake was complete. This chemical corporation -related article is a stub . You can help Misplaced Pages by expanding it . Adhesive Adhesive , also known as glue , cement , mucilage , or paste ,
623-492: A large collection of ochre samples from many sites across Australia. There are many words for ochre in Australian Aboriginal languages throughout Australia, including: The Māori people of New Zealand were found to be making extensive use of mineral ochre mixed with fish oil. Ochre was the predominant colouring agent used by Maori, and was used to paint their large waka taua (war canoe). Ochre prevented
712-468: A machine. For an adhesive to be effective it must have three main properties. Firstly, it must be able to wet the base material . Wetting is the ability of a liquid to maintain contact with a solid surface. It must also increase in strength after application, and finally it must be able to transmit load between the two surfaces/substrates being adhered. Adhesion, the attachment between adhesive and substrate may occur either by mechanical means, in which
801-476: A mixture of ingredients (typically polymers ) dissolved in a solvent . White glue , contact adhesives and rubber cements are members of the drying adhesive family. As the solvent evaporates, the adhesive hardens. Depending on the chemical composition of the adhesive, they will adhere to different materials to greater or lesser degrees. Polymer dispersion adhesives are milky-white dispersions often based on polyvinyl acetate (PVAc). They are used extensively in
890-433: A more lovely and perfect ochre pigment...And know that this ochre is a common pigment, particularly when working in fresco; that with other mixtures that, as i will explain to you, it is used for flesh colours, for drapery, for coloured mountains and buildings and hair and in general for many things. In early modern Malta, red ochre paint was commonly used on public buildings. The industrial process for making ochre pigment
979-595: A mouldable putty that hardened into handles. Earlier excavations at Le Moustier prevent conclusive identification of the archaeological culture and age, but the European Mousterian style of these tools suggests they are associated with Neanderthals during the late Middle Paleolithic , between 60,000 and 35,000 years before present. It is the earliest evidence of compound adhesive use in Europe. Pieces of ochre engraved with abstract designs have been found at
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#17327880658971068-487: A multi-component adhesive are not adhesive by nature. The individual components react with each other after being mixed and show full adhesion only on curing. The multi-component resins can be either solvent-based or solvent-less. The solvents present in the adhesives are a medium for the polyester or the polyurethane resin. The solvent is dried during the curing process. Pre-mixed and frozen adhesives (PMFs) are adhesives that are mixed, deaerated, packaged, and frozen. As it
1157-482: A paper revealed the discovery of a 5,200-year-old man nicknamed the " Tyrolean Iceman " or "Ötzi", who was preserved in a glacier near the Austria-Italy border. Several of his belongings were found with him including two arrows with flint arrowheads and a copper hatchet, each with evidence of organic glue used to connect the stone or metal parts to the wooden shafts. The glue was analyzed as pitch , which requires
1246-678: A permanent bond after several hours or days. Removable adhesives are designed to form a temporary bond, and ideally can be removed after months or years without leaving residue on the adherend. Removable adhesives are used in applications such as surface protection films, masking tapes , bookmark and note papers, barcode labels, price marking labels, promotional graphics materials, and for skin contact (wound care dressings, EKG electrodes, athletic tape, analgesic and trans-dermal drug patches, etc.). Some removable adhesives are designed to repeatedly stick and unstick. They have low adhesion, and generally cannot support much weight. Pressure-sensitive adhesive
1335-513: A practice was common to the Celts of the British Isles , bog iron being particularly abundant in the midlands of Ireland . Ochre has uses other than as paint: "tribal peoples alive today . . . use either as a way to treat animal skins or else as an insect repellent, to staunch bleeding, or as protection from the sun. Ochre may have been the first medicament." Red ochre has been used as
1424-399: A solution to the problem that water-based adhesives, commonly used in packaging at that time, failed in humid climates, causing packages to open. However, water-based adhesives are still of strong interest as they typically do not contain volatile solvents. Anaerobic adhesives cure when in contact with metal, in the absence of oxygen. They work well in a close-fitting space, as when used as
1513-527: A specific archaeological period in the Woodlands c. 1000 –400 BC. California Native Americans such as the Tongva and Chumash were also known to use red ochre as body paint. Researchers diving into dark submerged caves on Mexico's Yucatán Peninsula have found evidence of an ambitious mining operation starting 12,000 years ago and lasting two millennia for red ochre. In Newfoundland , red ochre
1602-555: A stronger product and protects the gum from disintegrating under wet conditions. The ability to produce stronger adhesives allowed middle Stone Age humans to attach stone segments to sticks in greater variations, which led to the development of new tools. A study of material from Le Moustier indicates that Middle Paleolithic people, possibly Neanderthals , used glue made from a mixture of ocher and bitumen to make hand grips for cutting and scraping stone tools. More recent examples of adhesive use by prehistoric humans have been found at
1691-411: A term which refers to whether the adhesive chemically reacts in order to harden. Alternatively, they can be organized either by their starting physical phase or whether their raw stock is of natural or synthetic origin. Adhesives may be found naturally or produced synthetically. The earliest human use of adhesive-like substances was approximately 200,000 years ago, when Neanderthals produced tar from
1780-522: A waxy waterproof coating on structures. The reddle was sold as a ready-made mixture to farmers and herders by travelling workers called reddlemen. In Classical antiquity , the finest red ochre came from a Greek colony on the Black Sea where the modern city of Sinop in Turkey is located. It was carefully regulated, expensive and marked by a special seal, and this colour was called sealed Sinope. Later
1869-469: A wide range of materials. Ethylene-vinyl acetate -based hot-melts are particularly popular for crafts because of their ease of use and the wide range of common materials they can join. A glue gun (shown at right) is one method of applying hot adhesives. The glue gun melts the solid adhesive, then allows the liquid to pass through its barrel onto the material, where it solidifies. Thermoplastic glue may have been invented around 1940 by Procter & Gamble as
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#17327880658971958-512: Is also the name of the colours produced by this pigment, especially a light brownish-yellow. A variant of ochre containing a large amount of hematite , or dehydrated iron oxide, has a reddish tint known as red ochre (or, in some dialects, ruddle ). The word ochre also describes clays coloured with iron oxide derived during the extraction of tin and copper . Ochre is a family of earth pigments, which includes yellow ochre, red ochre, purple ochre, sienna, and umber. The major ingredient of all
2047-400: Is any non-metallic substance applied to one or both surfaces of two separate items that binds them together and resists their separation. The use of adhesives offers certain advantages over other binding techniques such as sewing , mechanical fastenings , and welding . These include the ability to bind different materials together, the more efficient distribution of stress across a joint,
2136-433: Is applied the components react and cross-link. This type of adhesive includes thermoset epoxies , urethanes , and polyimides . Moisture curing adhesives cure when they react with moisture present on the substrate surface or in the air. This type of adhesive includes cyanoacrylates and urethanes . Natural adhesives are made from organic sources such as vegetable starch ( dextrin ), natural resins, or animals (e.g.
2225-605: Is difficult to pinpoint an exact shade or hue of red that would be considered the traditional " fishing stage red". In the Bonavista Bay area one man maintained that seal oil mixed with the ochre gave the sails a purer red colour, while cod liver oil would give a "foxy" colour, browner in hue. During the Renaissance, yellow and red ochre pigments were widely used in painting panels and frescoes. The colours vary greatly from region to region, depending upon whether
2314-593: Is greater than the surface energy of the adhesive. However, high-strength adhesives have high surface energy. Thus, they bond poorly to low-surface-energy polymers or other materials. To solve this problem, surface treatment can be used to increase the surface energy as a preparation step before adhesive bonding. Importantly, surface preparation provides a reproducible surface allowing consistent bonding results. The commonly used surface activation techniques include plasma activation , flame treatment and wet chemistry priming. There are several factors that could contribute to
2403-458: Is highlighted by the great number of powders of this color found in the containers. The powders were probably used to give a hue to cheeks or to lips. Besides these uses as make-up powders, we can also assume a ritual use of ointments and powders containing cinnabar or ochre, applied to the face and the forehead during preparation rituals of the bodies. The discovery of red paint traces on bones and skulls suggests that these practices were common among
2492-436: Is necessary for PMFs to remain frozen before use, once they are frozen at −80 °C they are shipped with dry ice and are required to be stored at or below −40 °C. PMF adhesives eliminate mixing mistakes by the end user and reduce exposure of curing agents that can contain irritants or toxins. PMFs were introduced commercially in the 1960s and are commonly used in aerospace and defense. One-part adhesives harden via
2581-494: Is particularly intensive: it is not unusual to find a layer of the cave floor impregnated with a purplish red to a depth of eight inches. The size of these ochre deposits raises a problem not yet solved. The colouring is so intense that practically all the loose ground seems to consist of ochre. One can imagine that the Aurignacians regularly painted their bodies red, dyed their animal skins, coated their weapons, and sprinkled
2670-516: Is used in Post-it notes . Pressure-sensitive adhesives are manufactured with either a liquid carrier or in 100% solid form. Articles are made from liquid PSAs by coating the adhesive and drying off the solvent or water carrier. They may be further heated to initiate a cross-linking reaction and increase molecular weight . 100% solid PSAs may be low viscosity polymers that are coated and then reacted with radiation to increase molecular weight and form
2759-815: The Russian Revolution and the Spanish Civil War . Ochre also began to face growing competition from newly synthetic pigment industry. The quarries in Roussillon, Rustrel, the Mines of Bruoux closed one by one. Today, the last quarry in activity is in Gargas (Vaucluse) and belongs to the Société des Ocres de France. Ochre, both red and yellow, appear as tinctures in South African heraldry ;
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2848-555: The Vaucluse department of Provence , in France. Thanks to the process invented by Astier and refined by his successors, ochre pigments from Vaucluse were exported across Europe and around the world. It was not only used for artists paints and house paints; it also became an important ingredient for the early rubber industry. Ochre from Vaucluse was an important French export until the mid-20th century, when major markets were lost due to
2937-598: The Western Desert , Kimberley and Arnhem Land regions, and occur in many archaeological sites. The practice of ochre painting has been prevalent among Aboriginal Australians for over 40,000 years. Pleistocene burials with red ochre date as early as 40,000 BP and ochre plays a role in expressing symbolic ideologies of the earliest arrivals to the continent. Ochre has been used for millennia by Aboriginal people for body decoration, sun protection , mortuary practices, cave painting, bark painting and other artwork, and
3026-469: The cave of Altamira in Spain ( c. 16,500 –15,000 BC). The cave of Lascaux has an image of a horse coloured with yellow ochre estimated to be 17,300 years old. Neolithic burials may have used red ochre pigments symbolically, either to represent a return to the earth or possibly as a form of ritual rebirth, in which the colour may symbolize blood and a hypothesized Great Goddess . The use of ochre
3115-728: The national coat of arms , adopted in 2000, includes red ochre , while (yellow) ochre appears in the arms of the University of Transkei . Ochre is also used as a symbol of Indigenous Australians , and appears on the Flag of the Northern Territory and on the flags of the Taungurung and Aṉangu people. A reddleman named Diggory Venn was prominently described in Thomas Hardy 's 1878 novel entitled The Return of
3204-758: The 20th century has the development of synthetic adhesives accelerated rapidly, and innovation in the field continues to the present. The earliest evidence of human adhesive use was discovered in central Italy when three stone implements were discovered with birch bark tar indications. The tools were dated to about 200,000 before present in the Middle Paleolithic . It is the earliest example of tar- hafted stone tools. An experimental archeology study published in 2019 demonstrated how birch bark tar can be produced in an easier, more discoverable process. It involves directly burning birch bark under an overhanging rock surface in an open-air environment and collecting
3293-480: The British fishing industry, where it was combined with oil and used to coat sails to protect them from seawater, giving them a reddish colour. The ochre was boiled in great caldrons, together with tar , tallow and oak bark , the last ingredient giving the name of barking yards to the places where the hot mixture was painted on to the sails, which were then hung up to dry. In 1894, a theft case provided insights into
3382-477: The Greeks and Romans made great contributions to the development of adhesives. Wood veneering and marquetry were developed, the production of animal and fish glues refined, and other materials utilized. Egg-based pastes were used to bond gold leaves, and incorporated various natural ingredients such as blood, bone, hide, milk, cheese, vegetables, and grains. The Greeks began the use of slaked lime as mortar while
3471-530: The Latin and Italian name sinopia was given to wide range of dark red ochre pigments. Roman triumphators painted their faces red, perhaps to imitate the red-painted flesh of statues of the Gods. The Romans used yellow ochre in their paintings to represent gold and skin tones, and as a background colour. It is found frequently in the murals of Pompeii . Ochre pigments are plentiful across Australia, especially
3560-559: The Phoenicians as for other populations.” Greater-quality pigments and more intricate applications would typically indicate people of greater rank or particular significance within the community. Moreover, the presence and quality of pigments in a burial site may indicate the identity or social standing of the deceased. In addition to acting as offerings to the gods and protective symbols, pigments were employed to adorn grave goods including pottery, amulets, and other objects, so elevating
3649-614: The Romans furthered mortar development by mixing lime with volcanic ash and sand. This material, known as pozzolanic cement , was used in the construction of the Roman Colosseum and Pantheon. The Romans were also the first people known to have used tar and beeswax as caulk and sealant between the wooden planks of their boats and ships. In Central Asia, the rise of the Mongols in approximately AD 1000 can be partially attributed to
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3738-845: The adherend. The bond has strength because the adhesive is hard enough to resist flow when stress is applied to the bond. Once the adhesive and the adherend are in close proximity, molecular interactions, such as van der Waals forces , become involved in the bond, contributing significantly to its ultimate strength. PSAs are designed for either permanent or removable applications. Examples of permanent applications include safety labels for power equipment, foil tape for HVAC duct work, automotive interior trim assembly, and sound/vibration damping films. Some high performance permanent PSAs exhibit high adhesion values and can support kilograms of weight per square centimeter of contact area, even at elevated temperatures. Permanent PSAs may initially be removable (for example to recover mislabeled goods) and build adhesion to
3827-607: The adhesive works its way into small pores of the substrate, or by one of several chemical mechanisms. The strength of adhesion depends on many factors, including the means by which it occurs. In some cases, an actual chemical bond occurs between adhesive and substrate. Thiolated polymers , for example, form chemical bonds with endogenous proteins such as mucus glycoproteins, integrins or keratins via disulfide bridges. Because of their comparatively high adhesive properties, these polymers find numerous biomedical applications. In others, electrostatic forces, as in static electricity, hold
3916-684: The adhesive, or they may be high viscosity materials that are heated to reduce viscosity enough to allow coating, and then cooled to their final form. Major raw material for PSA's are acrylate -based polymers. Contact adhesives form high shear-resistance bonds with a rapid cure time. They are often applied in thin layers for use with laminates , such as bonding Formica to countertops, and in footwear, as in attaching outsoles to uppers. Natural rubber and polychloroprene (Neoprene) are commonly used contact adhesives. Both of these elastomers undergo strain crystallization . Contact adhesives must be applied to both surfaces and allowed some time to dry before
4005-427: The adhesive. In this case the surfaces of both adherends after debonding will be covered by fractured adhesive. The crack may propagate in the center of the layer or near an interface. For this last case, the cohesive fracture can be said to be "cohesive near the interface". Adhesive fracture (sometimes referred to as interfacial fracture ) is when debonding occurs between the adhesive and the adherend. In most cases,
4094-404: The afterlife, and social hierarchy, thus providing a richer understanding of Phoenician customs and values. Ochre was the most commonly used pigment for painting walls in the ancient Mediterranean world . In Ancient Greece , red ochre was called μίλτος, míltos (hence Miltiades : "red-haired" or "ruddy"). In ancient Athens when Assembly was called, a contingent of public slaves would sweep
4183-463: The burial sites of ancient tribes. Archaeologists studying the sites found that approximately 6,000 years ago the tribesmen had buried their dead together with food found in broken clay pots repaired with tree resins. Another investigation by archaeologists uncovered the use of bituminous cements to fasten ivory eyeballs to statues in Babylonian temples dating to approximately 4000 BC. In 2000,
4272-646: The climax of the practice coinciding broadly with the emergence of Homo sapiens. Evidence of ochre's use in Australia is more recent, dated to 50,000 years ago, while new research has uncovered evidence in Asia that is dated to 40,000 years ago. A re-examination of artifacts uncovered in 1908 at Le Moustier rock shelters in France has identified Mousterian stone tools that were attached to grips made of ochre and bitumen . The grips were formulated with 55% ground goethite ochre and 45% cooked liquid bitumen to create
4361-414: The cost-effectiveness of an easily mechanized process, and greater flexibility in design. Disadvantages of adhesive use include decreased stability at high temperatures, relative weakness in bonding large objects with a small bonding surface area, and greater difficulty in separating objects during testing. Adhesives are typically organized by the method of adhesion followed by reactive or non-reactive ,
4450-539: The development and production of new plastics and resins due to the First and Second World Wars. These advances greatly improved the development of adhesives by allowing the use of newly developed materials that exhibited a variety of properties. With changing needs and ever evolving technology, the development of new synthetic adhesives continues to the present. However, due to their low cost, natural adhesives are still more commonly used. Adhesives are typically organized by
4539-418: The development of cyclized rubber treated in strong acids. By 1927, this process was used to produce solvent-based thermoplastic rubber cements for metal to rubber bonding. Natural rubber-based sticky adhesives were first used on a backing by Henry Day (US Patent 3,965) in 1845. Later these kinds of adhesives were used in cloth backed surgical and electric tapes. By 1925, the pressure-sensitive tape industry
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#17327880658974628-570: The digestive system while others, which are rich in iron, can assist with lethargy and fatigue. Ochre is also often mixed with plant oils and animal fats to create other medicines. This ochre was mined by Aboriginal people in pits and quarries across Australia; there are over 400 recorded sites, and many of these (including the Ochre Pits in the Tjoritja / West MacDonnell National Park ) are still in use. The National Museum of Australia has
4717-414: The dry distillation of birch bark for use in binding stone tools to wooden handles. The first references to adhesives in literature appeared approximately 2000 BC. The Greeks and Romans made great contributions to the development of adhesives. In Europe, glue was not widely used until the period AD 1500–1700. From then until the 1900s increases in adhesive use and discovery were relatively gradual. Only since
4806-508: The drying out of the wood in canoes and the carvings of meeting houses; later missionaries estimated that it would last for 30 years. It was also roughly smeared over the face, especially by women, to keep off insects. Solid chunks of ochre were ground on a flat but rough surfaced rock to produce the powder. In Newfoundland its use is most often associated with the Beothuk , whose use of red ochre led them to be referred to as "Red Indians" by
4895-415: The earth of mountains, where particular seams like sulphur are found. And there, where these seams are, sinopia, green earth and other types of pigment are found...And the abovementioned pigments running through this landscape looked as a scar on the face of a man or of a woman looks...I went in behind with my little knife, prospecting at the scar of this pigment; and in this way, I promise you, I never sampled
4984-418: The failure of two adhered surfaces. Sunlight and heat may weaken the adhesive. Solvents can deteriorate or dissolve adhesive. Physical stresses may also cause the separation of surfaces. When subjected to loading, debonding may occur at different locations in the adhesive joint. The major fracture types are the following: Cohesive fracture is obtained if a crack propagates in the bulk polymer which constitutes
5073-644: The first Europeans to Newfoundland. The Beothuk may have also used yellow ochre to colour their hair. It was also used by the Maritime Archaic as evidenced by its discovery in the graves of over 100 individuals during an archaeological excavation at Port au Choix . Its use was widespread at times in the Eastern Woodlands cultural area of Canada and the US; the Red Ocher people complex refers to
5162-741: The first commercial glue plant was established in The Netherlands. This plant produced glues from animal hides. In 1750, the first British glue patent was issued for fish glue. The following decades of the next century witnessed the manufacture of casein glues in German and Swiss factories. In 1876, the first U.S. patent (number 183,024) was issued to the Ross brothers for the production of casein glue. The first U.S. postage stamps used starch-based adhesives when issued in 1847. The first US patent (number 61,991) on dextrin (a starch derivative) adhesive
5251-454: The good range and power of the bows of Genghis Khan's hordes. These bows were made of a bamboo core, with horn on the belly (facing towards the archer) and sinew on the back, bound together with animal glue . In Europe, glue fell into disuse until the period AD 1500–1700. At this time, world-renowned cabinet and furniture makers such as Thomas Chippendale and Duncan Phyfe began to use adhesives to hold their products together. In 1690,
5340-425: The grains of sand from the particles of ochre. The remaining mixture was then decanted in large basins, to further separate the ochre from the sand. The water was then drained, and the ochre was dried, cut into bricks, crushed, sifted, and then classified by colour and quality. The best quality was reserved for artists' pigments. In Britain , ochre was mined at Brixham , England . It became an important product for
5429-545: The ground of their dwellings, and that a paste of ochre was used for decorative purposes in every phase of their domestic life. We must assume no less, if we are to account for the veritable mines of ochre on which some of them lived... The Ancient Picts were said to paint themselves "Iron Red" according to the Gothic historian Jordanes . Frequent references in Irish myth to "red men" ( Gaelic : Fer Dearg) make it likely that such
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#17327880658975518-418: The heating of tar during its production. The retrieval of this tar requires a transformation of birch bark by means of heat, in a process known as pyrolysis. The first references to adhesives in literature appeared in approximately 2000 BC. Further historical records of adhesive use are found from the period spanning 1500–1000 BC. Artifacts from this period include paintings depicting wood gluing operations and
5607-408: The local clay was richer in yellowish limonite or reddish hematite. The red earth from Pozzuoli near Naples was a salmon pink, while the pigment from Tuscany contained manganese, making it a darker reddish brown called terra di siena, or sienna earth. The 15th-century painter Cennino Cennini described the uses of ochre pigments in his famous treatise on painting. This pigment is found in
5696-403: The manufacturing of items in many industrial markets such as electronics, telecommunications, medical, aerospace, glass, and optical. Unlike traditional adhesives, UV light curing adhesives not only bond materials together but they can also be used to seal and coat products. They are generally acrylic-based. Heat curing adhesives consist of a pre-made mixture of two or more components. When heat
5785-488: The method of adhesion. These are then organized into reactive and non-reactive adhesives, which refers to whether the adhesive chemically reacts in order to harden. Alternatively they can be organized by whether the raw stock is of natural, or synthetic origin, or by their starting physical phase . There are two types of adhesives that harden by drying: solvent-based adhesives and polymer dispersion adhesives , also known as emulsion adhesives . Solvent-based adhesives are
5874-537: The milk protein casein and hide-based animal glues ). These are often referred to as bioadhesives . One example is a simple paste made by cooking flour in water. Starch-based adhesives are used in corrugated board and paper sack production, paper tube winding, and wallpaper adhesives . Casein glue is mainly used to adhere glass bottle labels. Animal glues have traditionally been used in bookbinding, wood joining, and many other areas but now are largely replaced by synthetic glues except in specialist applications like
5963-564: The name PY-43 (Pigment yellow 43) on the label, following the Colour Index International system. Over recent decades, red ochre has played a pivotal role in discussions about the cognitive and cultural evolution of early modern humans during the African Middle Stone Age. In Africa, evidence for the processing and use of red ochre pigments has been dated by archaeologists to around 300,000 years ago,
6052-582: The occurrence of adhesive fracture for a given adhesive goes along with smaller fracture toughness. Other types of fracture include: Ochre Ochre ( / ˈ oʊ k ər / OH -kər ; from Ancient Greek ὤχρα ( ṓkhra ) , from ὠχρός ( ōkhrós ) 'pale'), iron ochre , or ocher in American English , is a natural clay earth pigment , a mixture of ferric oxide and varying amounts of clay and sand. It ranges in colour from yellow to deep orange or brown. It
6141-596: The ochres is iron(III) oxide-hydroxide , known as limonite , which gives them a yellow colour. A range of other minerals may also be included in the mixture: When natural sienna and umber pigments are heated, they are dehydrated and some of the limonite is transformed into hematite, giving them more reddish colours, called burnt sienna and burnt umber. Ochres are non-toxic and can be used to make an oil paint that dries quickly and covers surfaces thoroughly. Modern ochre pigments often are made using synthetic iron oxide. Pigments which use natural ochre pigments indicate it with
6230-595: The open space of the Agora with ropes dipped in miltos : those citizens that loitered there instead of moving to the Assembly area would risk having their clothes stained with the paint. This prevented them from wearing these clothes in public again, as failure to attend the Assembly incurred a fine. In England, red ochre was also known as "raddle", "reddle", or "ruddle" and was used to mark sheep and can also be used as
6319-528: The preservation of animal skins, among other uses. At Lake Mungo , in Western New South Wales , burial sites have been excavated and burial materials, including ochre-painted bones, have been dated to the arrival of people in Australia; " Mungo Man " (LM3) was buried sprinkled with red ochre at least 30,000 BP, and possibly as early as 60,000 BP. Ochre was also widely used as medicine and, when ingested, some ochres have an antacid effect on
6408-627: The production and repair of stringed instruments. Albumen made from the protein component of blood has been used in the plywood industry. Masonite , a wood hardboard, was originally bonded using natural wood lignin , an organic polymer , though most modern particle boards such as MDF use synthetic thermosetting resins. Synthetic adhesives are made out of organic compounds . Many are based on elastomers , thermoplastics , emulsions , and thermosets . Examples of thermosetting adhesives are: epoxy , polyurethane , cyanoacrylate and acrylic polymers. The first commercially produced synthetic adhesive
6497-659: The site of the Blombos Cave in South Africa, dated to around 75,000 years ago. " Mungo Man " (LM3) in Australia was buried sprinkled with red ochre around 40,000 years ago. In Wales, the paleolithic burial called the Red Lady of Paviland from its coating of red ochre has been dated to around 33,000 years before present. Paintings of animals made with red and yellow ochre pigments have been found in paleolithic sites at Pech Merle in France (ca. 25,000 years old), and
6586-571: The spiritual purity of the interment. The visual impact of red ochre could also have been intended to preserve the appearance of the body or make it presentable for mourning ceremonies, ensuring that the deceased was honored appropriately. This vivid color would enhance the overall visual and emotional impact of funerary displays. In essence, the use of red ochre and other pigments in Phoenician funerary contexts highlights their cultural and symbolic importance, reflecting deep-seated beliefs about death,
6675-403: The substances together. A third mechanism involves the van der Waals forces that develop between molecules. A fourth means involves the moisture-aided diffusion of the glue into the substrate, followed by hardening. The quality of adhesive bonding depends strongly on the ability of the adhesive to efficiently cover (wet) the substrate area. This happens when the surface energy of the substrate
6764-502: The tar that builds up on the rock. Although sticky enough, plant-based, single-component adhesives can be brittle and vulnerable to environmental conditions. The first use of compound adhesives was discovered in Sibudu, South Africa. Here, 70,000-year-old stone segments that were once inserted in axe hafts were discovered covered with an adhesive composed of plant gum and red ochre (natural iron oxide) as adding ochre to plant gum produces
6853-473: The two surfaces are pushed together. Some contact adhesives require as long as 24 hours to dry completely before the surfaces are to be held together. Once the surfaces are pushed together, the bond forms very quickly. Clamps are typically not needed due to the rapid bond formation. Hot adhesives , also known as hot melt adhesives , are thermoplastics applied in molten form (in the 65–180 °C range) which solidify on cooling to form strong bonds between
6942-555: The use of the pigment as a food adulterant in sausage roll production whereby the accused apprentice was taught to soak brown bread in red ochre, salt , and pepper to give the appearance of beef sausage for the filling. As noted above, the industrial process for making ochre pigment was developed by the French scientist Jean-Étienne Astier in the 1780s, using the ochre mines and quarries in Roussillon , Rustrel, or Gargas in
7031-433: The woodworking and packaging industries. They are also used with fabrics and fabric-based components, and in engineered products such as loudspeaker cones. Pressure-sensitive adhesives (PSA) form a bond by the application of light pressure to bind the adhesive with the adherend. They are designed to have a balance between flow and resistance to flow. The bond forms because the adhesive is soft enough to flow (i.e., "wet") to
7120-560: Was Karlsons Klister in the 1920s. Applicators of different adhesives are designed according to the adhesive being used and the size of the area to which the adhesive will be applied. The adhesive is applied to either one or both of the materials being bonded. The pieces are aligned and pressure is added to aid in adhesion and rid the bond of air bubbles. Common ways of applying an adhesive include brushes, rollers, using films or pellets, spray guns and applicator guns ( e.g. , caulk gun ). All of these can be used manually or automated as part of
7209-459: Was born. Today, sticky notes, Scotch Tape , and other tapes are examples of pressure-sensitive adhesives (PSA). A key step in the development of synthetic plastics was the introduction of a thermoset plastic known as Bakelite phenolic in 1910. Within two years, phenolic resin was applied to plywood as a coating varnish. In the early 1930s, phenolics gained importance as adhesive resins. The 1920s, 1930s, and 1940s witnessed great advances in
7298-495: Was considered to be eternal and indestructible. The skin and bones of the gods were believed to be made of gold. The Egyptians used yellow ochre extensively in tomb painting, though occasionally they used orpiment , which made a brilliant colour, but was highly toxic, since it was made with arsenic . In tomb paintings, men were always shown with brown faces, women with yellow ochre or gold faces. Red ochre in Ancient Egypt
7387-417: Was developed by the French scientist Jean-Étienne Astier in the 1780s. He was from Roussillon in the Vaucluse department of Provence , and he was fascinated by the cliffs of red and yellow clay in the region. He invented a process to make the pigment on a large scale. First the clay was extracted from open pits or mines. The raw clay contained about 10 to 20 percent ochre. Then he washed the clay to separate
7476-403: Was evocative of blood and energy, red ochre represented life, death, and rebirth. It also represented the desire for resurrection and the belief in an afterlife. In order to honor the deceased and get them ready for their passage to the afterlife, these pigments, particularly red ochre, were most likely applied to their body or other grave goods as part of the burial rites. “Phoenicians' love of red
7565-503: Was formed in 2005 through the merger of Borden Chemicals, Resolution Performance Products, Resolution Specialty Materials, and Bakelite AG. At that time they also acquired Pacific Epoxy Products. In 2010, the parent holding companies of Momentive Performance Materials Inc. and Hexion Specialty Chemicals Inc. merged to form Momentive Performance Materials Holdings LLC . In 2015, this combined company renamed itself to Hexion Inc. In February 2020, Hexion Inc. announced that it has entered into
7654-439: Was issued in 1867. Natural rubber was first used as material for adhesives in 1830, which marked the starting point of the modern adhesive. In 1862, a British patent (number 3288) was issued for the plating of metal with brass by electrodeposition to obtain a stronger bond to rubber. The development of the automobile and the need for rubber shock mounts required stronger and more durable bonds of rubber and metal. This spurred
7743-569: Was mixed with some type of liquid raw material to create a rough paint. The liquid material was usually seal oil or cod liver oil in Newfoundland and Labrador, while Scandinavian recipes sometimes called for linseed oil . Red ochre paint was sometimes prepared months in advance and allowed to sit, and the smell of ochre paint being prepared is still remembered today. Variations in local recipes, shades of ore, and type of oil used resulted in regional variations in colour. Because of this, it
7832-423: Was the pigment of choice for use in vernacular outbuildings and work buildings associated with the cod fishery. Deposits of ochre are found throughout Newfoundland, notably near Fortune Harbour and at Ochre Pit Cove. While earliest settlers may have used locally collected ochre, people were later able to purchase pre-ground ochre through local merchants, largely imported from England . The dry ingredient, ochre,
7921-805: Was used as a rouge, or lip gloss for women. Ochre-coloured lines were also discovered on the Unfinished obelisk at the northern region of the Aswan Stone Quarry , marking work sites. Ochre clays were also used medicinally in Ancient Egypt: such use is described in the Ebers Papyrus from Egypt, dating to about 1550 BC. Pigments, particularly red ochre, were essential to grave rituals in ancient Phoenician society. They were more than just cosmetics; they also had important symbolic and ritualistic connotations. With its vivid color that
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