Cellophane
Encyclopedia
Cellulose
Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to over ten thousand β linked D-glucose units....
. Its low permeability to air, oil
Oil
An oil is any substance that is liquid at ambient temperatures and does not mix with water but may mix with other oils and organic solvents. This general definition includes vegetable oils, volatile essential oils, petrochemical oils, and synthetic oils....
s, grease
Fat
Fats consist of a wide group of compounds that are generally soluble in organic solvents and generally insoluble in water. Chemically, fats are triglycerides, triesters of glycerol and any of several fatty acids. Fats may be either solid or liquid at room temperature, depending on their structure...
s, bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
and water
Water
Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...
makes it useful for food packaging
Food packaging
Food packaging is packaging for food. It requires protection, tampering resistance, and special physical, chemical, or biological needs. It also shows the product that is labeled to show any nutrition information on the food being consumed....
. Cellophane is in many countries a registered trade mark of Innovia Films Ltd, Cumbria, UK.
Production
Wood
Wood is a hard, fibrous tissue found in many trees. It has been used for hundreds of thousands of years for both fuel and as a construction material. It is an organic material, a natural composite of cellulose fibers embedded in a matrix of lignin which resists compression...
, cotton
Cotton
Cotton is a soft, fluffy staple fiber that grows in a boll, or protective capsule, around the seeds of cotton plants of the genus Gossypium. The fiber is almost pure cellulose. The botanical purpose of cotton fiber is to aid in seed dispersal....
, hemp
Hemp
Hemp is mostly used as a name for low tetrahydrocannabinol strains of the plant Cannabis sativa, of fiber and/or oilseed varieties. In modern times, hemp has been used for industrial purposes including paper, textiles, biodegradable plastics, construction, health food and fuel with modest...
or other sources is dissolved in alkali
Alkali
In chemistry, an alkali is a basic, ionic salt of an alkali metal or alkaline earth metal element. Some authors also define an alkali as a base that dissolves in water. A solution of a soluble base has a pH greater than 7. The adjective alkaline is commonly used in English as a synonym for base,...
and carbon disulfide
Carbon disulfide
Carbon disulfide is a colorless volatile liquid with the formula CS2. The compound is used frequently as a building block in organic chemistry as well as an industrial and chemical non-polar solvent...
to make a solution called viscose
Viscose
Viscose is a viscous organic liquid used to make rayon and cellophane. Viscose is becoming synonymous with rayon, a soft material commonly used in shirts, shorts, coats, jackets, and other outer wear.-Manufacture:...
, which is then extruded through a slit into a bath of dilute sulfuric acid
Sulfuric acid
Sulfuric acid is a strong mineral acid with the molecular formula . Its historical name is oil of vitriol. Pure sulfuric acid is a highly corrosive, colorless, viscous liquid. The salts of sulfuric acid are called sulfates...
and sodium sulfate
Sodium sulfate
Sodium sulfate is the sodium salt of sulfuric acid. When anhydrous, it is a white crystalline solid of formula Na2SO4 known as the mineral thenardite; the decahydrate Na2SO4·10H2O has been known as Glauber's salt or, historically, sal mirabilis since the 17th century. Another solid is the...
to reconvert the viscose into cellulose. The film is then passed through several more baths, one to remove sulfur
Sulfur
Sulfur or sulphur is the chemical element with atomic number 16. In the periodic table it is represented by the symbol S. It is an abundant, multivalent non-metal. Under normal conditions, sulfur atoms form cyclic octatomic molecules with chemical formula S8. Elemental sulfur is a bright yellow...
, one to bleach the film, and one to add glycerin to prevent the film from becoming brittle.
A similar process, using a hole (a spinneret
Spinneret (polymers)
Spinneret refers to a multi-pored device through which a plastic polymer melt is extruded to form fibers. Streams of viscous polymer usually exit into cool air or liquid to solidify. The individual polymer chains tend to align in the fiber because of viscous flow. This airstream liquid-to-fiber...
) instead of a slit, is used to make a fibre called rayon
Rayon
Rayon is a manufactured regenerated cellulose fiber. Because it is produced from naturally occurring polymers, it is neither a truly synthetic fiber nor a natural fiber; it is a semi-synthetic or artificial fiber. Rayon is known by the names viscose rayon and art silk in the textile industry...
. Chemically, cellophane, rayon and cellulose are polymer
Polymer
A polymer is a large molecule composed of repeating structural units. These subunits are typically connected by covalent chemical bonds...
s of glucose
Glucose
Glucose is a simple sugar and an important carbohydrate in biology. Cells use it as the primary source of energy and a metabolic intermediate...
and contain the chemical element
Chemical element
A chemical element is a pure chemical substance consisting of one type of atom distinguished by its atomic number, which is the number of protons in its nucleus. Familiar examples of elements include carbon, oxygen, aluminum, iron, copper, gold, mercury, and lead.As of November 2011, 118 elements...
s carbon
Carbon
Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds...
, hydrogen
Hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...
and oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
.
History
Cellophane was invented by Swiss chemist Jacques E. BrandenbergerJacques E. Brandenberger
Jacques Edwin Brandenberger was a Swiss chemist and textile engineer who in 1908 invented cellophane. He was awarded the Franklin Institute's Elliott Cresson Medal in 1937.-External links:*...
while employed by Blanchisserie et Teinturerie de Thaon. 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 on to 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. 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.
Whitman's
Whitman's
Whitman's is one of America's largest and oldest brands of boxed chocolates. Whitman's confections have been produced since 1842, originally by Stephen Whitman in Philadelphia and currently by Russell Stover Candies...
candy company initiated use of cellophane for candy
Candy
Candy, specifically sugar candy, is a confection made from a concentrated solution of sugar in water, to which flavorings and colorants are added...
wrapping in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
in 1912 for their Whitman's Sampler. They remained the largest user of imported cellophane from France until nearly 1924, when DuPont
DuPont
E. I. du Pont de Nemours and Company , commonly referred to as DuPont, is an American chemical company that was founded in July 1802 as a gunpowder mill by Eleuthère Irénée du Pont. DuPont was the world's third largest chemical company based on market capitalization and ninth based on revenue in 2009...
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. Du Pont hired chemist William Hale Charch, who spent three years developing a nitrocellulose
Nitrocellulose
Nitrocellulose is a highly flammable compound formed by nitrating cellulose through exposure to nitric acid or another powerful nitrating agent. When used as a propellant or low-order explosive, it is also known as guncotton...
lacquer that, when applied to Cellophane, made it moisture proof. 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 Du Pont's sales and 25% of its profits.
The British textile company Courtaulds
Samuel Courtauld (industrialist)
Samuel Courtauld was an industrialist and Unitarian, chiefly remembered as the driving force behind the rapid growth of the Courtauld textile business in Britain....
' 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 in conjunction with the Cellophane Company and its French parent company CTA. A major production facility was constructed at Bridgwater
Bridgwater
Bridgwater is a market town and civil parish in Somerset, England. It is the administrative centre of the Sedgemoor district, and a major industrial centre. Bridgwater is located on the major communication routes through South West England...
, Somerset
Somerset
The ceremonial and non-metropolitan county of Somerset in South West England borders Bristol and Gloucestershire to the north, Wiltshire to the east, Dorset to the south-east, and Devon to the south-west. It is partly bounded to the north and west by the Bristol Channel and the estuary of the...
, England, from 1935–1937, employing 3,000 workers.
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 tapesPressure 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 pressure, without the need for solvent, heat, or water for activation...
as Sellotape
Sellotape
Sellotape is a British brand of transparent, cellulose-based, pressure sensitive adhesive tape, and is the leading brand of clear, pressure sensitive tape in the United Kingdom. Sellotape is generally used for joining, sealing, attaching and mending...
and Scotch Tape
Scotch Tape
Scotch Tape is a brand name used for certain pressure sensitive tapes manufactured by 3M as part of the company's Scotch brand.- History :The precursor to the current tapes was developed in the 1930s in Minneapolis, Minnesota by Richard Drew to seal a then-new transparent material known as...
, a semi-permeable membrane in a certain type of battery
Battery (electricity)
An electrical battery is one or more electrochemical cells that convert stored chemical energy into electrical energy. Since the invention of the first battery in 1800 by Alessandro Volta and especially since the technically improved Daniell cell in 1836, batteries have become a common power...
, as dialysis tubing
Dialysis tubing
Dialysis Tubing or visking tubing is a type of semi- or partially permeable membrane tubing made from regenerated cellulose or cellophane. It can be used for diffusion with solutes or osmosis if used with water only. Osmosis is when water passes through a semi-permeable layer to reach equilibrium...
(Visking tubing) and as a release agent in the manufacture of fibreglass and rubber
Rubber
Natural rubber, also called India rubber or caoutchouc, is an elastomer that was originally derived from latex, a milky colloid produced by some plants. The plants would be ‘tapped’, that is, an incision made into the bark of the tree and the sticky, milk colored latex sap collected and refined...
products. In the UK and in many other countries "cellophane" is a registered trademark and the property of Innovia Films Group, based in Wigton
Wigton
Wigton is a small market town and civil parish outside the Lake District, in the administrative county of Cumbria in England, and traditionally in Cumberland. It is the bustling and thriving centre of the Solway Plain, situated between the Caldbeck Fells and the Solway coast...
. However, in the US "cellophane" has become genericized
Genericized trademark
A genericized trademark is a trademark or brand name that has become the colloquial or generic description for, or synonymous with, a general class of product or service, rather than as an indicator of source or affiliation as intended by the trademark's holder...
, and is often used informally to refer to a wide variety of plastic
Plastic
A plastic material is any of a wide range of synthetic or semi-synthetic organic solids used in the manufacture of industrial products. Plastics are typically polymers of high molecular mass, and may contain other substances to improve performance and/or reduce production costs...
film products, even those not made of cellulose, such as plastic wrap
Plastic wrap
Plastic wrap, cling film , cling wrap or food wrap, is a thin plastic film typically used for sealing food items in containers to keep them fresh over a longer period of time...
.
Cellophane sales have dwindled since the 1960s, due to alternative packaging options and the fact that viscose
Viscose
Viscose is a viscous organic liquid used to make rayon and cellophane. Viscose is becoming synonymous with rayon, a soft material commonly used in shirts, shorts, coats, jackets, and other outer wear.-Manufacture:...
is becoming less common. The polluting effects of carbon disulfide
Carbon disulfide
Carbon disulfide is a colorless volatile liquid with the formula CS2. The compound is used frequently as a building block in organic chemistry as well as an industrial and chemical non-polar solvent...
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. Cellophane is the most popular material for manufacturing cigar
Cigar
A cigar is a tightly-rolled bundle of dried and fermented tobacco that is ignited so that its smoke may be drawn into the mouth. Cigar tobacco is grown in significant quantities in Brazil, Cameroon, Cuba, the Dominican Republic, Honduras, Indonesia, Mexico, Nicaragua, Philippines, and the Eastern...
packaging; its permeability to moisture makes cellophane the perfect product for this application as cigars must be allowed to "breathe" while in storage.
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.
See also
- Bioplastics
- Genericized trademarkGenericized trademarkA genericized trademark is a trademark or brand name that has become the colloquial or generic description for, or synonymous with, a general class of product or service, rather than as an indicator of source or affiliation as intended by the trademark's holder...
- British CellophaneBritish CellophaneBritish Cellophane Ltd was a joint venture company formed in 1935 between La Cellophane SA and Courtaulds, when they began building a major factory for producing Cellophane in Bridgwater, Somerset, England....
- Jacques E. BrandenbergerJacques E. BrandenbergerJacques Edwin Brandenberger was a Swiss chemist and textile engineer who in 1908 invented cellophane. He was awarded the Franklin Institute's Elliott Cresson Medal in 1937.-External links:*...
- polarization
- birefringenceBirefringenceBirefringence, or double refraction, is the decomposition of a ray of light into two rays when it passes through certain anisotropic materials, such as crystals of calcite or boron nitride. The effect was first described by the Danish scientist Rasmus Bartholin in 1669, who saw it in calcite...
- light artLight artLight art is a form of visual art where main media of expression is light. Light has been used for architectural aesthetical effects throughout human history. However, the modern concept of light art emerged with the development of artificial light sources and experimenting modern art...