1.
Label
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A label is a piece of paper, polymer, cloth, metal, or other material affixed to a container or product, on which is written or printed information or symbols about the product or item. Information printed directly on a container or article can also be considered labeling, methods of production and attachment to packaging are many and various and may also be subject to internationally recognised standards. In many countries, hazardous products such as poisons or flammable liquids must have a warning label, labels may be used for any combination of identification, information, warning, instructions for use, environmental advice or advertising. They may be stickers, permanent or temporary labels or printed packaging, Permanent product identification by a label is commonplace, labels need to remain secure throughout the life of the product. For example, a VIN plate on an automobile must be resistant to heat, oils and tampering, similarly, removable product labels need to bond until they are removed. For example, a label on a new refrigerator has installation, usage and environmental information, packaging may have labeling attached to or integral with the package. These may carry pricing, barcodes, UPC identification, usage guidance, addresses, advertising, recipes and they also may be used to help resist or indicate tampering or pilferage. In industrial or military environments, asset labeling is used to identify assets for maintenance. Such labels are made of engraved Traffolyte or a similar material. They are usually tamper-evident, permanent or frangible and usually contain a barcode for electronic identification using readers, for example, the US Military uses a UID system for its assets. Garments normally carry separate care/treatment labels which, in regions, are subject to legislation. These labels typically indicate how the item should be washed, whether bleach can be used, textile labels may be woven into the garment or attached, and may be heat resistant, colorfast, washable, leather or PVC/Plastic. Printed labels are an alternative to woven labels, some upholstered furniture and mattresses have labels that are required by law, describing the contents of the stuffing. Textiles containing pesticides as an ingredient may also require government approval, a label including a company name or identification number and a material content list may also be required. Mailing labels identify the addressee, the sender and any information which may be useful in transit. Many software packages such as word processor and contact manager programs produce standardized mailing labels from a set that comply with postal standards. These labels may also include routing barcodes and special handling requirements to expedite delivery, piggyback labels are made from combining two layers of adhesive substrate. The bottom layer forms the backing for the top, the label can be applied to any object as normal, the top layer can be a removable label that can be applied elsewhere, which may change the message or marking on the remaining label underneath
2.
Adhesive
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The use of adhesives offers many advantages over binding techniques such as sewing, mechanical fastening, thermal bonding, etc. Adhesives are typically organized by the method of adhesion and 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, Adhesives may be found naturally or produced synthetically. The earliest human use of substances was approximately 200,000 years ago. The first references to adhesives in literature first appeared in approximately 2000 BCE, the Greeks and Romans made great contributions to the development of adhesives. In Europe, glue was not widely used until the period 1500–1700 CE, from then until the 1900s increases in adhesive use and discovery were relatively gradual. Only since the last century has the development of synthetic adhesives accelerated rapidly, the earliest use of adhesives was discovered in central Italy when two stone flakes partially covered with birch-bark tar and a third uncovered stone from the Middle Pleistocene era were found. This is thought to be the oldest discovered human use of tar-hafted stones, the birch-bark-tar adhesive is a simple, one-component adhesive. Although sticky enough, plant-based adhesives are brittle and vulnerable to environmental conditions, the first use of compound adhesives was discovered in Sibudu, South Africa. The ability to produce stronger adhesives allowed middle stone age humans to attach stone segments to sticks in greater variations, more recent examples of adhesive use by prehistoric humans have been found at 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 clay pots repaired with tree resins. The glue was analyzed as pitch, which requires 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 first appeared in approximately 2000 BCE, further historical records of adhesive use are found from the period spanning 1500–1000 BCE. Artifacts from this period include paintings depicting wood gluing operations and a made of wood. 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 -based glues. The ancient Egyptians also developed starch-based pastes for the bonding of papyrus to clothing, from 1 to 500 AD 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, egg-based pastes were used to bond gold leaves 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 the Romans furthered mortar development by mixing lime with volcanic ash and this material, known as pozzolanic cement, was used in the construction of the Roman Colosseum and Pantheon
3.
Paint
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Paint is any liquid, liquefiable, or mastic composition that, after application to a substrate in a thin layer, converts to a solid film. It is most commonly used to protect, color, or provide texture to objects, Paint can be made or purchased in many colors—and in many different types, such as watercolor, synthetic, etc. Paint is typically stored, sold, and applied as a liquid, in 2001 and 2004, South African archeologists reported finds in Blombos Cave of a 100, 000-year-old human-made ochre-based mixture that could have been used like paint. Further excavation in the cave resulted in the 2011 report of a complete toolkit for grinding pigments. Cave paintings drawn with red or yellow ochre, hematite, manganese oxide, ancient colored walls at Dendera, Egypt, which were exposed for years to the elements, still possess their brilliant color, as vivid as when they were painted about 2,000 years ago. The Egyptians mixed their colors with a substance, and applied them separately from each other without any blending or mixture. They appear to have used six colors, white, black, blue, red, yellow and they first covered the area entirely with white, then traced the design in black, leaving out the lights of the ground color. They used minium for red, and generally of a dark tinge, pliny mentions some painted ceilings in his day in the town of Ardea, which had been done prior to the foundation of Rome. He expresses great surprise and admiration at their freshness, after the lapse of so many centuries, Paint was made with the yolk of eggs and therefore, the substance would harden and adhere to the surface it was applied to. Pigment was made from plants, sand, and different soils, Most paints used either oil or water as a base. The process was done by hand by the painters and exposed them to lead poisoning due to the white-lead powder, in 1718, Marshall Smith invented a Machine or Engine for the Grinding of Colours in England. It is not known precisely how it operated, but it was a device that increased the efficiency of pigment grinding dramatically. By the proper onset of the Industrial Revolution, paint was being ground in steam-powered mills, interior house painting increasingly became the norm as the 19th century progressed, both for decorative reasons and because the paint was effective in preventing the walls rotting from damp. Linseed oil was also used as an inexpensive binder. In 1866, Sherwin-Williams in the United States opened as a large paint-maker and it was not until the stimulus of World War II created a shortage of linseed oil in the supply market that artificial resins, or alkyds, were invented. Cheap and easy to make, they held the color well. The vehicle is composed of the binder, or, if it is necessary to thin the binder with a diluent like solvent or water, it is the combination of binder + diluent. In this case, once the paint has dried or cured very nearly all of the diluent has evaporated, thus, an important quantity in coatings formulation is the vehicle solids, sometimes called the resin solids of the formula
4.
Lacquer
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The term lacquer is used for a number of hard and potentially shiny finishes applied to materials such as wood. These fall into a number of different groups. This dries to a hard and smooth surface layer which is durable, waterproof. Asian lacquer is sometimes painted with pictures, inlaid with shell and other materials, or carved, as well as dusted with gold and given other further decorative treatments. In modern techniques, lacquer means a range of clear or coloured wood finishes that dry by solvent evaporation or a process that produces a hard. The finish can be of any level from ultra matte to high gloss. It is also used for paint, which is a paint that typically dries better on a hard. Lacquer is more durable than shellac and these ultimately derive from Sanskrit lākshā, which was used for both the Lac insect and the scarlet resinous secretion it produces that was used as wood finish. Lac resin was once imported in quantity into Europe from India along with Eastern woods. Lacquer sheen is a measurement of the shine for a given lacquer, different manufacturers have their own names and standards for their sheen. The most common names from least shiny to most shiny are, flat, matte, egg shell, satin, semi-gloss, urushiol-based lacquers differ from most others, being slow-drying, and set by oxidation and polymerization, rather than by evaporation alone. In order for it to set properly it requires a humid, the phenols oxidize and polymerize under the action of an enzyme laccase, yielding a substrate that, upon proper evaporation of its water content, is hard. These lacquers produce very hard, durable finishes that are beautiful and very resistant to damage by water, acid, alkali or abrasion. The active ingredient of the resin is urushiol, a mixture of various phenols suspended in water, the resin is derived from a tree indigenous to China, species Toxicodendron vernicifluum, commonly known as the Lacquer Tree. The fresh resin from the T. vernicifluum trees causes urushiol-induced contact dermatitis, the Chinese treated the allergic reaction with crushed shellfish, which supposedly prevents lacquer from drying properly. Lacquer skills became very highly developed in Asia, and many highly decorated pieces were produced, the earliest extant lacquer object, a red wooden bowl, was unearthed at a Hemudu culture site in China. By the Han Dynasty, many centres of production became firmly established. The knowledge of the Chinese methods of the process spread from China during the Han, Tang and Song dynasties, eventually it was introduced to Korea, Japan, Southeast
5.
Adhesion
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Adhesion is the tendency of dissimilar particles or surfaces to cling to one another. The forces that cause adhesion and cohesion can be divided into several types, the intermolecular forces responsible for the function of various kinds of stickers and sticky tape fall into the categories of chemical adhesion, dispersive adhesion, and diffusive adhesion. In addition to the magnitudes of these intermolecular forces, there are certain emergent mechanical effects. Surface energy is defined as the work that is required to build an area of a particular surface. Another way to view the energy is to relate it to the work required to cleave a bulk sample. If the new surfaces are identical, the surface energy γ of each surface is equal to half the work of cleavage, W, γ = W11. If the surfaces are unequal, the Young-Dupré equation applies, W12 = γ1 + γ2 – γ12 and this methodology can also be used to discuss cleavage that happens in another medium, γ12 = W121 = W212. These two energy quantities refer to the energy that is needed to one species into two pieces while it is contained in a medium of the other species. Likewise for a three species system, γ13 + γ23 – γ12 = W12 + W33 – W13 – W23 = W132, there is no single theory covering adhesion, and particular mechanisms are specific to particular material scenarios. Five mechanisms of adhesion have been proposed to explain why one material sticks to another, Adhesive materials fill the voids or pores of the surfaces, other interlocking phenomena are observed on different length scales. Sewing is an example of two forming a large scale mechanical bond, velcro forms one on a medium scale. Two materials may form a compound at the joint, the strongest joints are where atoms of the two materials swap or share electrons. A weaker bond is formed if an atom in one molecule is attracted to an atom of nitrogen, oxygen, or fluorine in another molecule. Chemical adhesion occurs when the atoms of two separate surfaces form ionic, covalent, or hydrogen bonds. The engineering principle behind chemical adhesion in this sense is fairly straightforward, if surface molecules can bond and it bears mentioning that these attractive ionic and covalent forces are effective over only very small distances – less than a nanometer. In surface science, the term adhesion almost always refers to dispersive adhesion, in a typical solid-liquid-gas system the contact angle is used to evaluate adhesiveness indirectly, while a Centrifugal Adhesion Balance allows for direct quantitative adhesion measurements. Generally, cases where the angle is low are considered of higher adhesion per unit area. This approach assumes that the contact angle corresponds to a higher surface energy
6.
Wetting
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Wetting is the ability of a liquid to maintain contact with a solid surface, resulting from intermolecular interactions when the two are brought together. The degree of wetting is determined by a balance between adhesive and cohesive forces. Wetting deals with the three phases of materials, gas, liquid, and solid and it is now a center of attention in nanotechnology and nanoscience studies due to the advent of many nanomaterials in the past two decades. Wetting is important in the bonding or adherence of two materials, Wetting and the surface forces that control wetting are also responsible for other related effects, including capillary effects. There are two types of wetting, non-reactive wetting and active wetting, adhesive forces between a liquid and solid cause a liquid drop to spread across the surface. Cohesive forces within the cause the drop to ball up. The contact angle, as seen in Figure 1, is the angle at which the liquid–vapor interface meets the solid–liquid interface, the contact angle is determined by the result between adhesive and cohesive forces. As the tendency of a drop to spread out over a flat, solid surface increases, thus, the contact angle provides an inverse measure of wettability. A contact angle less than 90° usually indicates that wetting of the surface is very favorable, contact angles greater than 90° generally means that wetting of the surface is unfavorable, so the fluid will minimize contact with the surface and form a compact liquid droplet. For water, a surface may also be termed hydrophilic. Superhydrophobic surfaces have contact angles greater than 150°, showing almost no contact between the drop and the surface. This is sometimes referred to as the Lotus effect, the table describes varying contact angles and their corresponding solid/liquid and liquid/liquid interactions. For nonwater liquids, the term lyophilic is used for low contact angle conditions, similarly, the terms omniphobic and omniphilic apply to both polar and apolar liquids. Liquids can interact with two types of solid surfaces. Traditionally, solid surfaces have been divided into high-energy solids and low-energy types, the relative energy of a solid has to do with the bulk nature of the solid itself. Solids such as metals, glasses, and ceramics are known as hard solids because the bonds that hold them together are very strong. Thus, it takes an input of energy to break these solids. Most molecular liquids achieve complete wetting with high-energy surfaces, the other type of solids is weak molecular crystals where the molecules are held together essentially by physical forces
7.
Corrosion
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Corrosion is a natural process, which converts a refined metal to a more chemically-stable form, such as its oxide, hydroxide, or sulfide. It is the destruction of materials by chemical and/or electrochemical reaction with their environment. Corrosion engineering is the dedicated to controlling and stopping corrosion. In the most common use of the word, this means electrochemical oxidation of metal in reaction with an oxidant such as oxygen or sulfur, rusting, the formation of iron oxides, is a well-known example of electrochemical corrosion. This type of damage typically produces oxide or salt of the original metal, corrosion can also occur in materials other than metals, such as ceramics or polymers, although in this context, the term degradation is more common. Corrosion degrades the useful properties of materials and structures including strength, appearance and permeability to liquids, many structural alloys corrode merely from exposure to moisture in air, but the process can be strongly affected by exposure to certain substances. Corrosion can be concentrated locally to form a pit or crack, because corrosion is a diffusion-controlled process, it occurs on exposed surfaces. As a result, methods to reduce the activity of the surface, such as passivation and chromate conversion. However, some corrosion mechanisms are less visible and less predictable, in a galvanic couple, the more active metal corrodes at an accelerated rate and the more noble metal corrodes at a slower rate. When immersed separately, each metal corrodes at its own rate, what type of metal to use is readily determined by following the galvanic series. For example, zinc is used as a sacrificial anode for steel structures. Galvanic corrosion is of major interest to the industry and also anywhere water contacts pipes or metal structures. Factors such as size of anode, types of metal. The surface area ratio of the anode and cathode directly affects the corrosion rates of the materials, galvanic corrosion is often prevented by the use of sacrificial anodes. In any given environment, one metal will be more noble or more active than others. Two metals in electrical contact share the same electrons, so that the tug-of-war at each surface is analogous to competition for free electrons between the two materials. Using the electrolyte as a host for the flow of ions in the same direction, the resulting mass flow or electric current can be measured to establish a hierarchy of materials in the medium of interest. This hierarchy is called a series and is useful in predicting and understanding corrosion
8.
Wafer (electronics)
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Finally the individual microcircuits are separated and packaged. By 1960, silicon wafers were being manufactured in the U. S. by companies such as MEMC/SunEdison. In 1965, American engineers Eric O. Ernst, Donald J. Hurd, Wafers are formed of highly pure, nearly defect-free single crystalline material. One process for forming crystalline wafers is known as Czochralski growth invented by the Polish chemist Jan Czochralski. In this process, an ingot of high purity mono crystalline semiconductor, such as silicon or germanium. The boule is then sliced with a saw and polished to form wafers. The size of wafers for photovoltaics is 100–200 mm square and the thickness is 200–300 μm, in the future,160 μm will be the standard. Electronics use wafer sizes from 100–450 mm diameter, Wafers are cleaned with weak acids to remove unwanted particles, or repair damage caused during the sawing process. When used for cells, the wafers are textured to create a rough surface to increase their efficiency. The generated PSG is removed from the edge of the wafer in the etching, silicon wafers are available in a variety of diameters from 25.4 mm to 300 mm. Semiconductor fabrication plants are defined by the diameter of wafers that they are tooled to produce, Wafers grown using materials other than silicon will have different thicknesses than a silicon wafer of the same diameter. Wafer thickness is determined by the strength of the material used. This was the cost basis for increasing wafer size, conversion to 300 mm wafers from 200 mm wafers began in earnest in 2000, and reduced the price per die about 30-40%. However, this was not without significant problems for the industry, there is considerable resistance to the 450 mm transition despite the possible productivity improvement, because of concern about insufficient return on investment. Higher cost semiconductor fabrication equipment for larger wafers increases the cost of 450 mm fabs, converting to larger 450 mm wafers would reduce price per die only for process operations such as etch where cost is related to wafer count, not wafer area. Cost for processes such as lithography is proportional to wafer area, nikon plans to deliver 450-mm lithography equipment in 2015, with volume production in 2017. In November 2013 ASML paused development of 450-mm lithography equipment, citing uncertain timing of chipmaker demand, the time-line for 450 mm has not been fixed. Mark Durcan, CEO of Micron Technology, said in February 2014 that he expects 450 mm adoption to be delayed indefinitely or discontinued, “I am not convinced that 450mm will ever happen but, to the extent that it does, it’s a long way out in the future
9.
Textile
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A textile or cloth is a flexible material consisting of a network of natural or artificial fibres. Yarn is produced by spinning raw fibres of wool, flax, cotton, hemp, Textiles are formed by weaving, knitting, crocheting, knotting, or felting. The words fabric and cloth are used in textile assembly trades as synonyms for textile, however, there are subtle differences in these terms in specialized usage. Textile refers to any material made of interlacing fibres, a fabric is a material made through weaving, knitting, spreading, crocheting, or bonding that may be used in production of further goods. Cloth may be used synonymously with fabric but is often a piece of fabric used for a specific purpose. The word textile is from Latin, from the adjective textilis, meaning woven, from textus, the word cloth derives from the Old English clað, meaning a cloth, woven or felted material to wrap around one, from Proto-Germanic kalithaz. The discovery of dyed flax fibres in a cave in the Republic of Georgia dated to 34,000 BCE suggests textile-like materials were made even in prehistoric times. The production of textiles is a craft whose speed and scale of production has been altered almost beyond recognition by industrialization, however, for the main types of textiles, plain weave, twill, or satin weave, there is little difference between the ancient and modern methods. Textiles have an assortment of uses, the most common of which are for clothing and for such as bags. In the household they are used in carpeting, upholstered furnishings, window shades, towels, coverings for tables, beds, and other flat surfaces, in the workplace they are used in industrial and scientific processes such as filtering. Textiles are used in traditional crafts such as sewing, quilting. Textiles for industrial purposes, and chosen for other than their appearance, are commonly referred to as technical textiles. Technical textiles include textile structures for applications, medical textiles, geotextiles, agrotextiles. In all these applications stringent performance requirements must be met, woven of threads coated with zinc oxide nanowires, laboratory fabric has been shown capable of self-powering nanosystems using vibrations created by everyday actions like wind or body movements. Fashion designers commonly rely on textile designs to set their fashion collections apart from others, armani, the late Gianni Versace, and Emilio Pucci can be easily recognized by their signature print driven designs. Textiles can be made from many materials and these materials come from four main sources, animal, plant, mineral, and synthetic. In the past, all textiles were made from natural fibres, including plant, animal, in the 20th century, these were supplemented by artificial fibres made from petroleum. Textiles are made in various strengths and degrees of durability, from the finest gossamer to the sturdiest canvas, microfibre refers to fibres made of strands thinner than one denier
10.
Gas
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Gas is one of the four fundamental states of matter. A pure gas may be made up of atoms, elemental molecules made from one type of atom. A gas mixture would contain a variety of pure gases much like the air, what distinguishes a gas from liquids and solids is the vast separation of the individual gas particles. This separation usually makes a colorless gas invisible to the human observer, the interaction of gas particles in the presence of electric and gravitational fields are considered negligible as indicated by the constant velocity vectors in the image. One type of commonly known gas is steam, the gaseous state of matter is found between the liquid and plasma states, the latter of which provides the upper temperature boundary for gases. Bounding the lower end of the temperature scale lie degenerative quantum gases which are gaining increasing attention, high-density atomic gases super cooled to incredibly low temperatures are classified by their statistical behavior as either a Bose gas or a Fermi gas. For a comprehensive listing of these states of matter see list of states of matter. The only chemical elements which are stable multi atom homonuclear molecules at temperature and pressure, are hydrogen, nitrogen and oxygen. These gases, when grouped together with the noble gases. Alternatively they are known as molecular gases to distinguish them from molecules that are also chemical compounds. The word gas is a neologism first used by the early 17th-century Flemish chemist J. B. van Helmont, according to Paracelsuss terminology, chaos meant something like ultra-rarefied water. An alternative story is that Van Helmonts word is corrupted from gahst and these four characteristics were repeatedly observed by scientists such as Robert Boyle, Jacques Charles, John Dalton, Joseph Gay-Lussac and Amedeo Avogadro for a variety of gases in various settings. Their detailed studies ultimately led to a relationship among these properties expressed by the ideal gas law. Gas particles are separated from one another, and consequently have weaker intermolecular bonds than liquids or solids. These intermolecular forces result from interactions between gas particles. Like-charged areas of different gas particles repel, while oppositely charged regions of different gas particles attract one another, transient, randomly induced charges exist across non-polar covalent bonds of molecules and electrostatic interactions caused by them are referred to as Van der Waals forces. The interaction of these forces varies within a substance which determines many of the physical properties unique to each gas. A comparison of boiling points for compounds formed by ionic and covalent bonds leads us to this conclusion, the drifting smoke particles in the image provides some insight into low pressure gas behavior
11.
Solid
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Solid is one of the four fundamental states of matter. It is characterized by structural rigidity and resistance to changes of shape or volume, unlike a liquid, a solid object does not flow to take on the shape of its container, nor does it expand to fill the entire volume available to it like a gas does. The atoms in a solid are tightly bound to other, either in a regular geometric lattice or irregularly. The branch of physics deals with solids is called solid-state physics. Materials science is concerned with the physical and chemical properties of solids. Solid-state chemistry is concerned with the synthesis of novel materials, as well as the science of identification. The atoms, molecules or ions which make up solids may be arranged in a repeating pattern. Materials whose constituents are arranged in a regular pattern are known as crystals, in some cases, the regular ordering can continue unbroken over a large scale, for example diamonds, where each diamond is a single crystal. Almost all common metals, and many ceramics, are polycrystalline, in other materials, there is no long-range order in the position of the atoms. These solids are known as amorphous solids, examples include polystyrene, whether a solid is crystalline or amorphous depends on the material involved, and the conditions in which it was formed. Solids which are formed by slow cooling will tend to be crystalline, likewise, the specific crystal structure adopted by a crystalline solid depends on the material involved and on how it was formed. While many common objects, such as an ice cube or a coin, are chemically identical throughout, for example, a typical rock is an aggregate of several different minerals and mineraloids, with no specific chemical composition. Wood is an organic material consisting primarily of cellulose fibers embedded in a matrix of organic lignin. In materials science, composites of more than one constituent material can be designed to have desired properties, the forces between the atoms in a solid can take a variety of forms. For example, a crystal of sodium chloride is made up of sodium and chlorine. In diamond or silicon, the atoms share electrons and form covalent bonds, in metals, electrons are shared in metallic bonding. Some solids, particularly most organic compounds, are together with van der Waals forces resulting from the polarization of the electronic charge cloud on each molecule. The dissimilarities between the types of solid result from the differences between their bonding, metals typically are strong, dense, and good conductors of both electricity and heat
12.
Polytetrafluoroethylene
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Polytetrafluoroethylene is a synthetic fluoropolymer of tetrafluoroethylene that has numerous applications. The best known name of PTFE-based formulas is Teflon by Chemours. Chemours is a spin-off of DuPont Co. which discovered the compound in 1938, PTFE is a fluorocarbon solid, as it is a high-molecular-weight compound consisting wholly of carbon and fluorine. PTFE is hydrophobic, neither water nor water-containing substances wet PTFE, PTFE has one of the lowest coefficients of friction of any solid. PTFE is used as a coating for pans and other cookware. It is very non-reactive, partly because of the strength of carbon–fluorine bonds, where used as a lubricant, PTFE reduces friction, wear and energy consumption of machinery. It is commonly used as a material in surgical interventions. Also, it is employed as coating on catheters, this interferes with the ability of bacteria and other infectious agents to adhere to catheters. PTFE was accidentally discovered in 1938 by Roy Plunkett while he was working in New Jersey for DuPont. Since Plunkett was measuring the amount of gas used by weighing the bottle, he became curious as to the source of the weight and he found the bottles interior coated with a waxy white material that was oddly slippery. Analysis showed that it was polymerized perfluoroethylene, with the iron from the inside of the container having acted as a catalyst at high pressure, Kinetic Chemicals patented the new fluorinated plastic in 1941, and registered the Teflon trademark in 1945. By 1948, DuPont, which founded Kinetic Chemicals in partnership with General Motors, was producing two million pounds of Teflon brand PTFE per year in Parkersburg, West Virginia. In 1954, the wife of French engineer Marc Grégoire urged him to try the material he had been using on fishing tackle on her cooking pans and he subsequently created the first Teflon-coated, non-stick pans under the brandname Tefal. In the United States, Marion A. Trozzolo, who had been using the substance on scientific utensils, marketed the first US-made Teflon-coated pan, The Happy Pan, however, Tefal was not the only company to utilize PTFE in nonstick cookware coatings. Other cookware companies, such as Meyer Corporations Anolon, use Teflon nonstick coatings purchased from DuPont, in the 1990s, it was found that PTFE could be radiation cross-linked above its melting point in an oxygen-free environment. Electron beam processing is one example of radiation processing, cross-linked PTFE has improved high-temperature mechanical properties and radiation stability. This was significant because, for years, irradiation at ambient conditions has been used to break down PTFE for recycling. This radiation-induced chain scission allows it to be more easily reground, PTFE is produced by free-radical polymerization of tetrafluoroethylene
