Cellophane

Cellophane is a thin, transparent sheet made of regenerated cellulose. Its low permeability to air, oils, greases, bacteria, and water makes it useful for food packaging. Cellophane is highly permeable to water vapour, but may be coated with nitrocellulose lacquer to prevent this.

As well as food packaging, cellophane is used in transparent pressure-sensitive tape, tubing and many other similar applications.

Unlike many other similar materials, cellophane is biodegradable. However its manufacture employs toxic chemicals.

"Cellophane" is a generic term in some countries, while in other countries it is a registered trademark.

Cellofan
Transparent cellophane packaging with gingerbread and a printed cellophane bag with chocolate hearts.

Production

Cellulose from wood, cotton, hemp, or other sources is dissolved in alkali and carbon disulfide to make a solution called viscose, which is then extruded through a slit into a bath of dilute sulfuric acid and sodium sulfate to reconvert the viscose into cellulose. The film is then passed through several more baths, one to remove sulfur, one to bleach the film, and one to add softening materials such as glycerin to prevent the film from becoming brittle.

A similar process, using a hole (a spinneret) instead of a slit, is used to make a fibre called rayon. Chemically, cellophane, rayon and cellulose are polymers of glucose; they differ structurally rather than chemically.

History

Cellophane was invented by Swiss chemist Jacques E. Brandenberger while employed by Blanchisserie et Teinturerie de Thaon.[1] In 1900, inspired by seeing a wine spill on a restaurant's tablecloth, he decided to create a cloth that could repel liquids rather than absorb them. His first step was to spray a waterproof coating onto fabric, and he opted to try viscose. The resultant coated fabric was far too stiff, but the clear film easily separated from the backing cloth, and he abandoned his original idea as the possibilities of the new material became apparent.

It took ten years for Brandenberger to perfect his film, his chief improvement over earlier work with such films being to add glycerin to soften the material. By 1912 he had constructed a machine to manufacture the film, which he had named Cellophane, from the words cellulose and diaphane ("transparent"). Cellophane was patented that year.[2] The following year, the company Comptoir des Textiles Artificiels (CTA) bought the Thaon firm's interest in Cellophane and established Brandenberger in a new company, La Cellophane SA.[3]

Xanthogenate Cellulose Structural Formula V1
Cellulose is treated with alkali and carbon disulfide to yield viscose.
Cellophane
Cellophane can come in any color and is used in packaging different products in grocery stores.

Whitman's candy company initiated use of cellophane for candy wrapping in the United States in 1912 for their Whitman's Sampler. They remained the largest user of imported cellophane from France until nearly 1924, when DuPont built the first cellophane manufacturing plant in the US. Cellophane saw limited sales in the US at first since while it was waterproof, it was not moisture proof—it held water but was permeable to water vapor. This meant that it was unsuited to packaging products that required moisture proofing. DuPont hired chemist William Hale Charch, who spent three years developing a nitrocellulose lacquer that, when applied to Cellophane, made it moisture proof.[4] Following the introduction of moisture-proof Cellophane in 1927, the material's sales tripled between 1928 and 1930, and in 1938, Cellophane accounted for 10% of DuPont's sales and 25% of its profits.[3]

Cellophane played a crucial role in developing the self-service retailing of fresh meat, according to Roger Horowitz, who ran a historic study over meat-packing industry. Cellophane visibility helped customers know quality of meat before buying. Cellophane also allowed manufacturers to manipulate the appearance of a product by controlling oxygen and moisture levels to prevent discoloration of food.[5]

The British textile company Courtaulds' viscose technology had allowed it to diversify in 1930 into viscose film, which it named "Viscacelle". However, competition with Cellophane was an obstacle to its sales, and in 1935 it founded British Cellophane Limited (BCL) in conjunction with the Cellophane Company and its French parent company CTA.[6] A major production facility was constructed at Bridgwater, Somerset, England, from 1935 to 1937, employing 3,000 workers. BCL subsequently constructed plants in Cornwall, Ontario (BCL Canada), as an adjunct to the existing Courtaulds viscose rayon plant there (from which it bought the viscose solution (AKA dope)), and in 1957 at Barrow-in-Furness, Cumbria. Those last two plants were closed in the 1990s.

Present day

Cellulose film has been manufactured continuously since the mid-1930s and is still used today. As well as packaging a variety of food items, there are also industrial applications, such as a base for such self-adhesive tapes as Sellotape and Scotch Tape, a semi-permeable membrane in a certain type of battery, as dialysis tubing (Visking tubing), and as a release agent in the manufacture of fibreglass and rubber products. Cellophane is the most popular material for manufacturing cigar packaging; its permeability to moisture makes cellophane the perfect product for this application as cigars must be allowed to "breathe" while in storage.

Cellophane sales have dwindled since the 1960s, due to alternative packaging options. The polluting effects of carbon disulfide and other by-products of the process used to make viscose may have also contributed to this; however, cellophane itself is 100% biodegradable, and that has increased its popularity as a food wrapping.

Material properties

When placed between two plane polarizing filters, cellophane produces prismatic colours due to its birefringent nature. Artists have used this effect to create stained glass-like creations that are kinetic and interactive.

Cellophane is biodegradable, but highly toxic carbon disulfide is used in most cellophane production. Viscose factories vary widely in the amount of CS2 they expose their workers to, and most give no information about their quantitative safety limits or how well they keep to them.[7][8]

Branding

In the UK and in many other countries, "cellophane" is a registered trademark and the property of Futamura Chemical UK Ltd, based in Wigton, Cumbria, United Kingdom.[9] In the US and some other countries "cellophane" has become genericized, and is often used informally to refer to a wide variety of plastic film products, even those not made of cellulose,[10] such as plastic wrap.

See also

References

  1. ^ Carraher, Charles E. (Jr.) (2014). Carraher's Polymer Chemistry: Ninth Edition. Boca Raton Fl.: CRC Press, Taylor & Francis Group. p. 301. ISBN 978-1-4665-5203-6.
  2. ^ Carlisle, Rodney (2004). Scientific American Inventions and Discoveries, p.338. John Wiley & Sons, Inc., New Jersey. ISBN 0-471-24410-4.
  3. ^ a b Hounshell, David A.; John Kenly Smith (1988). Science and Corporate Strategy: Du Pont R&D, 1902–1980. Cambridge University Press. p. 170. ISBN 0-521-32767-9.
  4. ^ Winkler, John K. (1935). The Dupont Dynasty. Baltimore, MD: Waverly Press, Inc. p. 271.
  5. ^ Hisano, Ai. "Cellophane, the New Visuality, and the Creation of Self-Service Food Retailing" (PDF). Harvard Business School.
  6. ^ Davenport-Hines, Richard Peter Treadwell (1988). Enterprise, Management, and Innovation in British Business, 1914-80. Routledge. p. 61. ISBN 0-7146-3348-8.
  7. ^ http://www.abc.net.au/radionational/programs/healthreport/the-health-burden-of-viscose-rayon/8286870
  8. ^ Michelle Nijhuis. "Bamboo Boom: Is This Material for You?". Scientific American.
  9. ^ "Performance Films for Beverages" (PDF). Innovia Films. Archived from the original (PDF) on 31 March 2012. Retrieved 29 November 2010.
  10. ^ Modern petro based Cello Bags

External links

Cellophane noodles

Cellophane noodles, or Fensi (simplified Chinese: 粉丝; traditional Chinese: 粉絲; pinyin: fěnsī; literally: 'flour thread'), sometimes called glass noodles, are a type of transparent noodle made from starch (such as mung bean starch, potato starch, sweet potato starch, tapioca, or canna starch) and water.

They are generally sold in dried form, soaked to reconstitute, then used in soups, stir fried dishes, or spring rolls. They are called "cellophane noodles" or "glass noodles" because of their appearance when cooked, resembling cellophane, a clear material of a translucent light gray or brownish-gray color.

Cellophane noodles should not be confused with rice vermicelli, which are made from rice and are white in color rather than clear (after cooking in water).

Chicago (musical)

Chicago (Chicago: A Musical Vaudeville) is an American musical with music by John Kander, lyrics by Fred Ebb, and book by Ebb and Bob Fosse. Set in Jazz-age Chicago, the musical is based on a 1926 play of the same name by reporter Maurine Dallas Watkins about actual criminals and crimes she reported on. The story is a satire on corruption in the administration of criminal justice and the concept of the "celebrity criminal".

The original Broadway production opened in 1975 at the 46th Street Theatre and ran for 936 performances until 1977. Bob Fosse choreographed the original production, and his style is strongly identified with the show. Following a West End debut in 1979 which ran for 600 performances, Chicago was revived on Broadway in 1996, and a year later in the West End.

The Broadway revival holds the record as the longest-running musical revival and the longest-running American musical in Broadway history. It is the second longest-running show in Broadway history, behind only The Phantom of the Opera, having played its 7,486th performance on November 23, 2014, surpassing Cats. The West End revival became the longest-running American musical in West End history. Chicago has been staged in numerous productions around the world, and has toured extensively in the United States and United Kingdom. The 2002 film version of the musical won the Academy Award for Best Picture.

Epiretinal membrane

Epiretinal membrane is a disease of the eye in response to changes in the vitreous humor or more rarely, diabetes. It is also called macular pucker. Sometimes, as a result of immune system response to protect the retina, cells converge in the macular area as the vitreous ages and pulls away in posterior vitreous detachment (PVD). PVD can create minor damage to the retina, stimulating exudate, inflammation, and leucocyte response. These cells can form a transparent layer gradually and, like all scar tissue, tighten to create tension on the retina which may bulge and pucker (e.g., macular pucker), or even cause swelling or macular edema. Often this results in distortions of vision that are clearly visible as bowing ←→ when looking at lines on chart paper (or an Amsler grid) within the macular area, or central 1.0 degree of visual arc. Usually it occurs in one eye first, and may cause binocular diplopia or double vision if the image from one eye is too different from the image of the other eye. The distortions can make objects look different in size (usually larger = macropsia), especially in the central portion of the visual field, creating a localized or field dependent aniseikonia that cannot be fully corrected optically with glasses. Partial correction often improves the binocular vision considerably though. In the young (under 50 years of age), these cells occasionally pull free and disintegrate on their own; but in the majority of sufferers (over 60 years of age) the condition is permanent. The underlying photoreceptor cells, rod cells and cone cells, are usually not damaged unless the membrane becomes quite thick and hard; so usually there is no macular degeneration.

Heroes

Heroes may refer to:

Hero, one who displays courage and self-sacrifice for the greater good

Packaging and labeling

Packaging is the science, art and technology of enclosing or protecting products for distribution, storage, sale, and use. Packaging also refers to the process of designing, evaluating, and producing packages. Packaging can be described as a coordinated system of preparing goods for transport, warehousing, logistics, sale, and end use. Packaging contains, protects, preserves, transports, informs, and sells. In many countries it is fully integrated into government, business, institutional, industrial, and personal use.

Package labeling (American English) or labelling (British English) is any written, electronic, or graphic communication on the package or on a separate but associated label.

Pressure-sensitive tape

Pressure-sensitive tape, known also in various countries as PSA tape, adhesive tape, self-stick tape, sticky tape, or just tape, is an adhesive tape that will stick with application of pressure, without the need for a solvent (such as water) or heat for activation. It can be used in the home, office, industry, and institutions for a wide variety of purposes.

The tape consists of a pressure-sensitive adhesive coated onto a backing material such as paper, plastic film, cloth, or metal foil. Some have a removable release liner which protects the adhesive until the liner is removed. Some have layers of adhesives, primers, easy release materials, filaments, printing, etc. made for specific functions.

It will stick without the need for a solvent such as heat or water for activation. By contrast a "gummed" or "water activated" adhesive tape requires warm water for activation. Likewise, some "heat activated" tapes require heat.

Single-sided tapes allow bonding to a surface or joining of two adjacent or overlapping materials. Double-sided tape (adhesive on both sides) allows joining of two items back-to-back.

Pressure-sensitive adhesive was first developed in 1845 by Dr. Horace Day, a surgeon. Commercial tapes were introduced in the early twentieth century. Hundreds of patents have since been published on a wide variety of formulations and constructions.

Safia (band)

SAFIA is an Australian electronica, indie pop band formed in Canberra. They met at Radford College. They won the Groovin' the Moo competition in 2012 and were featured on Peking Duk's ARIA top 10 single, "Take Me Over".The band says the name comes from a song they wrote called "Sapphire", but it does not mean anything. The band have since found out that safia means serenity in Arabic.When it comes to the band's influences, they claim to have a very broad range of styles and genres but list artists like Purity Ring, Major Lazer, Feed Me, Chet Faker, Disclosure and James Blake.The band has also opened for Twenty One Pilots during their 2017 Emotional Roadshow Tour Pacific Leg which started in Wellington, New Zealand.

On 30 June 2016, the band announced the title of its debut album, Internal, which was released on 9 September 2016 and peaked at number 2 on the ARIA Charts.

On 13 October 2017, Safia released "Cellophane Rainbow".

In 2018, they released "Freakin' Out", which was the first track they wrote after their album "Internal".

The Troggs

The Troggs (originally called the Troglodytes) are an English garage rock band formed in Andover, Hampshire in May 1964. They had a number of hits in the United Kingdom and the United States. Their most famous songs include the US chart-toppers "Wild Thing", "With a Girl Like You" and "Love Is All Around", all of which sold over 1 million copies and were awarded gold discs. "Wild Thing" is ranked #257 on the Rolling Stone magazine's list of The 500 Greatest Songs of All Time and was an influence on garage rock and punk rock.

Viscose

Viscose is a semi-synthetic fiber. "Viscose" can mean:

A viscous solution of cellulose

A synonym of rayon

A specific term for viscose rayon—rayon made using the viscose (cellulose xanthate) processThe viscose process dissolves pulp with aqueous sodium hydroxide in the presence of carbon disulfide. This viscous solution bears the name viscose. The cellulose solution is used to spin the viscose rayon fiber, which may also be called viscose. Viscose rayon fiber is a soft fiber commonly used in dresses, linings, shirts, shorts, coats, jackets, and other outerwear. It is also used in industrial yarns (tyre cord), upholstery and carpets, and in the casting of cellophane.

This page is based on a Wikipedia article written by authors (here).
Text is available under the CC BY-SA 3.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.