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Adhesive Remover
Adhesive remover is a substance intended to break down and remove glue and its remnants from surfaces. Description Adhesive removers are intended to break down glue so that it can be removed from surfaces easily. Formulations may be designed to remove a broad range of adhesives or to address a specific bond. Many general purpose removers are intended to remove residue from adhesive tape. Formulations Adhesive removers are often based on organic solvents, which can dissolve or soften many adhesive polymers that do not dissolve in water. They may also contain a gelling agent, increasing viscosity so that the product sticks to the area to be treated rather than running off. Common solvents used include -limonene, aliphatic alkanes, and acetone. Heptane is also used as an adhesive remover by stamp collectors. Since 1974, the United States Postal Service has issued self-adhesive stamps that some collectors find difficult to separate from envelopes via the traditional method of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viscosity
The viscosity of a fluid is a measure of its resistance to deformation at a given rate. For liquids, it corresponds to the informal concept of "thickness": for example, syrup has a higher viscosity than water. Viscosity quantifies the internal frictional force between adjacent layers of fluid that are in relative motion. For instance, when a viscous fluid is forced through a tube, it flows more quickly near the tube's axis than near its walls. Experiments show that some stress (such as a pressure difference between the two ends of the tube) is needed to sustain the flow. This is because a force is required to overcome the friction between the layers of the fluid which are in relative motion. For a tube with a constant rate of flow, the strength of the compensating force is proportional to the fluid's viscosity. In general, viscosity depends on a fluid's state, such as its temperature, pressure, and rate of deformation. However, the dependence on some of these properties is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limonene
Limonene is a colorless liquid aliphatic hydrocarbon classified as a cyclic monoterpene, and is the major component in the oil of citrus fruit peels. The -isomer, occurring more commonly in nature as the fragrance of oranges, is a flavoring agent in food manufacturing. It is also used in chemical synthesis as a precursor to carvone and as a renewables-based solvent in cleaning products. The less common -isomer has a piny, turpentine-like odor, and is found in the edible parts of such plants as caraway, dill, and bergamot orange plants. Limonene takes its name from Italian ''limone'' ("lemon"). Limonene is a chiral molecule, and biological sources produce one enantiomer: the principal industrial source, citrus fruit, contains -limonene ((+)-limonene), which is the (''R'')-enantiomer. Racemic limonene is known as dipentene. -Limonene is obtained commercially from citrus fruits through two primary methods: centrifugal separation or steam distillation. Chemical reactions Limon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkane
In organic chemistry, an alkane, or paraffin (a historical trivial name that also has other meanings), is an acyclic saturated hydrocarbon. In other words, an alkane consists of hydrogen and carbon atoms arranged in a tree structure in which all the carbon–carbon bonds are single. Alkanes have the general chemical formula . The alkanes range in complexity from the simplest case of methane (), where ''n'' = 1 (sometimes called the parent molecule), to arbitrarily large and complex molecules, like pentacontane () or 6-ethyl-2-methyl-5-(1-methylethyl) octane, an isomer of tetradecane (). The International Union of Pure and Applied Chemistry (IUPAC) defines alkanes as "acyclic branched or unbranched hydrocarbons having the general formula , and therefore consisting entirely of hydrogen atoms and saturated carbon atoms". However, some sources use the term to denote ''any'' saturated hydrocarbon, including those that are either monocyclic (i.e. the cycloalkanes) or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetone
Acetone (2-propanone or dimethyl ketone), is an organic compound with the formula . It is the simplest and smallest ketone (). It is a colorless, highly volatile and flammable liquid with a characteristic pungent odour. Acetone is miscible with water and serves as an important organic solvent in its own right, in industry, home, and laboratory. About 6.7 million tonnes were produced worldwide in 2010, mainly for use as a solvent and production of methyl methacrylate (and from that PMMA) as well as bisphenol A.Acetone World Petrochemicals report, January 2010Stylianos Sifniades, Alan B. Levy, "Acetone" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005. It is a common building block in |
Stamp Collecting
Stamp collecting is the collecting of postage stamps and related objects. It is an area of philately, which is the study (or combined study and collection) of stamps. It has been one of the world's most popular hobbies since the late nineteenth century with the rapid growth of the postal service, as a never-ending stream of new stamps was produced by countries that sought to advertise their distinctiveness through their stamps. Collecting Stamp collecting is generally accepted as one of the areas that make up the wider subject of philately, which is the study of stamps. A philatelist may, but does not have to, collect stamps. It is not uncommon for the term ''philatelist'' to be used to mean a stamp collector. Many casual stamp collectors accumulate stamps for sheer enjoyment and relaxation without worrying about the tiny details. The creation of a large or comprehensive collection, however, generally requires some philatelic knowledge and will usually contain areas of philate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Postal Service
The United States Postal Service (USPS), also known as the Post Office, U.S. Mail, or Postal Service, is an independent agency of the executive branch of the United States federal government responsible for providing postal service in the U.S., including its insular areas and associated states. It is one of the few government agencies explicitly authorized by the U.S. Constitution. The USPS, as of 2021, has 516,636 career employees and 136,531 non-career employees. The USPS traces its roots to 1775 during the Second Continental Congress, when Benjamin Franklin was appointed the first postmaster general; he also served a similar position for the colonies of the Kingdom of Great Britain. The Post Office Department was created in 1792 with the passage of the Postal Service Act. It was elevated to a cabinet-level department in 1872, and was transformed by the Postal Reorganization Act of 1970 into the U.S. Postal Service as an independent agency. Since the early 1980s, m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Self-adhesive Stamp
A self-adhesive stamp is a postage stamp with a pressure-sensitive adhesive that does not require moistening in order to adhere to paper. They are usually issued on a removable backing paper. Stamp collectors criticized the format, because the rubber based adhesive used tended to progressively yellow the stamps. They also found them difficult to remove from covers, and to save in mint condition, though self-adhesives of recent years have improved in these respects. Artistamps have also been issued in a self-adhesive format. First adhesive stamps They were first issued by such tropical climates as Sierra Leone in February 1964 and Tonga in April 1969 in an attempt to avoid the tendency of traditional water-activated stamps to stick together in humid conditions. They also made die cutting into fanciful and unique shapes easier. In the UK The Royal Mail first issued self-adhesive stamps on 19 October 1993, with the introduction of books of 20 first class stamps; later a sec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adhesives
Adhesive, also known as glue, cement, mucilage, or paste, 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, or welding. These include the ability to bind different materials together, the more efficient distribution of stress across a joint, 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'', a term which refers to whether the adhesive chemically reacts in order to harden. Alternatively, they can be organized eithe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
