|
Durium
Durium is a highly durable synthetic resin developed in 1929. It was used in phonograph records, as well as in the casting process for metallic type and in the aeronautics industry. Origin It is a resorcinol-formaldehyde resin, the result of research by Hal T. Beans, professor of chemistry at Columbia University. Properties The resin is flexible, tasteless, odorless, fire and waterproof. It is highly resistant to heat and was heated to in production of records. It is fast-setting, reducing the production cost of items made from it. Applications Being resistant to fire and water, the resin was used as a substitute for varnish on aeronautical parts. It was commercialized by Durium Products Company (renamed Durium Products, Inc., from 1931) as the medium for Hit of the Week records, from 1930 to 1932. The resin was bonded to a cardboard substrate and, being much lighter than its competitor shellac Shellac () is a resin secreted by the female lac bug on trees in the fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hit Of The Week
Hit of the Week was an American record label founded in 1930 that sold low-priced records made of Durium instead of the usual shellac. History Around 1930, several types of thin, flexible records made of various plastic formulations were introduced in Europe, such as the German Phonycord, French Pathé Cellodisc, British Filmophone and Goodson, and Spanish Delfos records. In the US, this short-lived trend was represented by Hit of the Week records, which were made of a sturdy brown paper base coated with Durium, a lightweight synthetic resin. The records tended to have a low-frequency rumble due to their texture, and their audio fidelity was generally inferior than most ordinary shellac records of the time. Unusually, Hit of the Week records were recorded on one side only, an early practice in the disc record industry which most other manufacturers had generally abandoned around 1910. As a consequence of being uncoated on the other side, they have a strong tendency to curl and now ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Durium Jr Record
Durium is a highly durable synthetic resin developed in 1929. It was used in phonograph records, as well as in the casting process for metallic type and in the aeronautics industry. Origin It is a resorcinol-formaldehyde resin, the result of research by Hal T. Beans, professor of chemistry at Columbia University. Properties The resin is flexible, tasteless, odorless, fire and waterproof. It is highly resistant to heat and was heated to in production of records. It is fast-setting, reducing the production cost of items made from it. Applications Being resistant to fire and water, the resin was used as a substitute for varnish on aeronautical parts. It was commercialized by Durium Products Company (renamed Durium Products, Inc., from 1931) as the medium for Hit of the Week records, from 1930 to 1932. The resin was bonded to a cardboard substrate and, being much lighter than its competitor shellac Shellac () is a resin secreted by the female lac bug on trees in the fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synthetic Resin
Synthetic resins are industrially produced resins, typically viscous substances that convert into rigid polymers by the process of curing. In order to undergo curing, resins typically contain reactive end groups, such as acrylates or epoxides. Some synthetic resins have properties similar to natural plant resins, but many do not. Synthetic resins are of several classes. Some are manufactured by esterification of organic compounds. Some are thermosetting plastics in which the term "resin" is loosely applied to the reactant(s), the product, or both. "Resin" may be applied to one of two monomers in a copolymer, the other being called a "hardener", as in epoxy resins. For thermosetting plastics that require only one monomer, the monomer compound is the "resin". For example, liquid methyl methacrylate is often called the "resin" or "casting resin" while in the liquid state, before it polymerizes and "sets". After setting, the resulting poly(methyl methacrylate) (PMMA) is often renam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Movable Type
Movable type (US English; moveable type in British English) is the system and technology of printing and typography that uses movable components to reproduce the elements of a document (usually individual alphanumeric characters or punctuation marks) usually on the medium of paper. The world's first movable type printing technology for paper books was made of porcelain materials and was invented around AD 1040 in China during the Northern Song dynasty by the inventor Bi Sheng (990–1051). The earliest printed paper money with movable metal type to print the identifying code of the money was made in 1161 during the Song dynasty. In 1193, a book in the Song dynasty documented how to use the copper movable type. The oldest extant book printed with movable metal type, Jikji, was printed in Korea in 1377 during the Goryeo dynasty. The spread of both movable-type systems was, to some degree, limited to primarily East Asia. The development of the printing press in Europe may have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Resorcinol
Resorcinol (or resorcin) is an organic compound with the formula C6H4(OH)2. It is one of three isomeric benzenediols, the 1,3-isomer (or '' meta''-isomer). Resorcinol crystallizes from benzene as colorless needles that are readily soluble in water, alcohol, and ether, but insoluble in chloroform and carbon disulfide. Production Resorcinol is produced in several steps from benzene, starting with dialkylation with propylene to give 1,3-diisopropylbenzene. Oxidation and Hock rearrangement of this disubstituted arene gives acetone and resorcinol. Resorcinol is an expensive chemical, produced in only a very few locations around the world (to date only four commercial plants are known to be operative: in the United States, Germany,China and Japan), and as such it is the determining factor in the cost of PRF adhesives. Many additional routes exist for resorcinol. It was formerly produced by disulfonation of benzene followed by hydrolysis of the 1,3-disulfonate. This method ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formaldehyde
Formaldehyde ( , ) (systematic name methanal) is a naturally occurring organic compound with the formula and structure . The pure compound is a pungent, colourless gas that polymerises spontaneously into paraformaldehyde (refer to section Forms below), hence it is stored as an aqueous solution (formalin), which is also used to store animal specimens. It is the simplest of the aldehydes (). The common name of this substance comes from its similarity and relation to formic acid. Formaldehyde is an important precursor to many other materials and chemical compounds. In 1996, the installed capacity for the production of formaldehyde was estimated at 8.7 million tons per year. It is mainly used in the production of industrial resins, e.g., for particle board and coatings. Forms Formaldehyde is more complicated than many simple carbon compounds in that it adopts several diverse forms. These compounds can often be used interchangeably and can be interconverted. *Molecular formald ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Columbia University
Columbia University (also known as Columbia, and officially as Columbia University in the City of New York) is a private research university in New York City. Established in 1754 as King's College on the grounds of Trinity Church in Manhattan, Columbia is the oldest institution of higher education in New York and the fifth-oldest institution of higher learning in the United States. It is one of nine colonial colleges founded prior to the Declaration of Independence. It is a member of the Ivy League. Columbia is ranked among the top universities in the world. Columbia was established by royal charter under George II of Great Britain. It was renamed Columbia College in 1784 following the American Revolution, and in 1787 was placed under a private board of trustees headed by former students Alexander Hamilton and John Jay. In 1896, the campus was moved to its current location in Morningside Heights and renamed Columbia University. Columbia scientists and scholars have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The New York Times
''The New York Times'' (''the Times'', ''NYT'', or the Gray Lady) is a daily newspaper based in New York City with a worldwide readership reported in 2020 to comprise a declining 840,000 paid print subscribers, and a growing 6 million paid digital subscribers. It also is a producer of popular podcasts such as '' The Daily''. Founded in 1851 by Henry Jarvis Raymond and George Jones, it was initially published by Raymond, Jones & Company. The ''Times'' has won 132 Pulitzer Prizes, the most of any newspaper, and has long been regarded as a national " newspaper of record". For print it is ranked 18th in the world by circulation and 3rd in the U.S. The paper is owned by the New York Times Company, which is publicly traded. It has been governed by the Sulzberger family since 1896, through a dual-class share structure after its shares became publicly traded. A. G. Sulzberger, the paper's publisher and the company's chairman, is the fifth generation of the family to head the pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shellac
Shellac () is a resin secreted by the female lac bug on trees in the forests of India and Thailand. It is processed and sold as dry flakes and dissolved in alcohol to make liquid shellac, which is used as a brush-on colorant, food glaze and wood finish. Shellac functions as a tough natural primer, sanding sealant, tannin-blocker, odour-blocker, stain, and high-gloss varnish. Shellac was once used in electrical applications as it possesses good insulation qualities and it seals out moisture. Phonograph and 78 rpm gramophone records were made of it until they were replaced by vinyl long-playing records from 1948 onwards. From the time it replaced oil and wax finishes in the 19th century, shellac was one of the dominant wood finishes in the western world until it was largely replaced by nitrocellulose lacquer in the 1920s and 1930s. Etymology ''Shellac'' comes from ''shell'' and ''lac'', a calque of French , 'lac in thin pieces', later , 'gum lac'. Most European langua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Time (magazine)
''Time'' (stylized in all caps) is an American news magazine based in New York City. For nearly a century, it was published Weekly newspaper, weekly, but starting in March 2020 it transitioned to every other week. It was first published in New York City on March 3, 1923, and for many years it was run by its influential co-founder, Henry Luce. A European edition (''Time Europe'', formerly known as ''Time Atlantic'') is published in London and also covers the Middle East, Africa, and, since 2003, Latin America. An Asian edition (''Time Asia'') is based in Hong Kong. The South Pacific edition, which covers Australia, New Zealand, and the Pacific Islands, is based in Sydney. Since 2018, ''Time'' has been published by Time USA, LLC, owned by Marc Benioff, who acquired it from Meredith Corporation. History ''Time'' has been based in New York City since its first issue published on March 3, 1923, by Briton Hadden and Henry Luce. It was the first weekly news magazine in the United St ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.png "Click for more on -> The New York Times")
