Buy Cellulose Acetate
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Eastman Chemical is a supplier of raw materials used in the Graphic Arts & Inks industry. With cellulose esters, sulfopolyesters, solvents, specialty and polymer additives, tackifiers, and resin intermediates, its ingredients cover a host of lithographic, flexographic, and gravure printing ink applications. Eastman also provides arylide intermediates for formulating organic pigments used in printing inks.
Cellulose acetate is one of the highest quality and best premium materials for the construction of eyeglasses for a number of different reasons. It is highly durable, resistant to temperature changes, comfortable to wear for an extended period of time, hypoallergenic, renewable, one of the best plastics for dye absorption and for the display of bright and vibrant colors, and it can be easily crafted into amazing geometric forms.
At Classic Specs you will find the majority of the glasses constructed from this premium material, ensuring that any option that you purchase from our online store will last you for years with proper care. The cellulose acetate that Classic Specs uses for its glasses is also imported from Italy from a professional family owned factory.
Amazingly strong and durableCellulose acetate is one of the strongest and most durable materials available for eyeglasses. It can withstand a great amount of physical stress, while maintaining its original shape amazingly well and with excellent elasticity. The tough fibers and structure of cellulose acetate are strong and resistant breaking down even if the glasses are worn for many years.
Hypoallergenic and renewableCellulose acetate is also hypoallergenic, meaning that it does not react with the skin, which can be very important for those who suffer from allergies. The feeling of cellulose acetate on the skin is also one of its top benefits, as it is described as having an organic or natural feeling compared to many other materials.
Incredible shapes and vivid colorsCellulose acetate can also be produced with a wide range of different shapes for eyeglasses and vivid colors that stay bright even when the glasses are worn frequently. You can see the diverse range of different shapes of eyeglasses at Classic Specs to get an idea about how easy it is to sculpt cellulose acetate into innovative frame styles. The material also absorbs frame dyes quite unlike any other, with amazing coloration results that are bold, shiny and vibrant. Different patterns just as the tortoise pattern can be easily coated onto the material.
As previously said, Cellulose Acetate is a natural polymer obtained from vegetable cellulose, the most widely spread organic compound in nature. By reacting cellulose with acetic anhydride Cellulose Acetate is obtained. Plasticizers are then added to Cellulose Acetate to improve its physical characteristics and workability.
Cellulose Acetate Butyrate (CAB) is an amorphous, transparent thermoplastic quite like cellulose acetate but more expensive and tougher with improved weathering resistance and lower moisture absorption.
Gas-permeable cellulose acetate butyrate (CAB) contact lenses may often be worn succesfully by aphakic and other patients who are unable to wear hard contact lenses. The comfort characteristics of the CAB lenses are betweeen those of hard and soft contact lenses. They are much more permeable to O2 and CO2 than soft lenses and thus are less apt to cause edema. They are more flexible and more wettable than hard lenses. This study presents 50 patients who, having had to discontinue wearing hard contact lenses because of discomfort, diffuse central corneal edema, or visual problems, were fitted with CAB contact lenses. Thirty of the fifty were able to wear the CAB lenses successfully.
In biochemistry, cellulose acetate refers to any acetate ester of cellulose, usually cellulose diacetate. It was first prepared in 1865. A bioplastic, cellulose acetate is used as a film base in photography, as a component in some coatings, and as a frame material for eyeglasses;[1] it is also used as a synthetic fiber in the manufacture of cigarette filters and playing cards. In photographic film, cellulose acetate film replaced nitrate film in the 1950s, being far less flammable and cheaper to produce.
In 1865, French chemist Paul Schützenberger discovered that cellulose reacts with acetic anhydride to form cellulose acetate. The German chemists Arthur Eichengrün and Theodore Becker invented the first soluble forms of cellulose acetate in 1903.[2]
In 1904, Camille Dreyfus and his younger brother Henri performed chemical research and development on cellulose acetate in a shed in their father's garden in Basel, Switzerland, which was then a center of the dye industry. For five years, the Dreyfus brothers studied and experimented in a systematic manner in Switzerland and France. By 1910, they were producing film for the motion picture industry, and a small but constantly growing amount of acetate lacquer, called \"dope\", was sold to the expanding aircraft industry to coat the fabric covering wings and fuselage.[3]
In 1913, after some twenty thousand separate experiments, they produced excellent laboratory samples of continuous filament yarn, something that had eluded the cellulose acetate industry to this time.[3] Unfortunately, the outbreak of World War I postponed commercial development of this process.
In November 1914, the British Government invited Dr. Camille Dreyfus to come to England to manufacture acetate dope, and the \"British Cellulose and Chemical Manufacturing Co\" was set up. In 1917, after the United States had entered the war, the U.S. War Department invited Dr. Dreyfus to establish a similar factory in the U.S. Both operations were run successfully throughout the war.
After the war, attention returned to the production of acetate fibers. The first yarn was of fair quality, but sales resistance was heavy, and silk associates worked zealously to discredit acetate and discourage its use. However, the thermoplastic nature of acetate made it an excellent fiber for moiré because the pattern was permanent and did not wash away. The same characteristic also made permanent pleating a commercial fact for the first time, and gave great style impetus to the whole dress industry.[3]
The mixing of silk and acetate in fabrics was accomplished at the beginning, and almost at once cotton was also blended, thus making possible low-cost fabrics by means of a fiber which then was cheaper than silk or acetate. Today, acetate is blended with silk, cotton, wool, nylon, etc. to give fabrics excellent wrinkle recovery, good heft, handle, draping quality, quick drying, proper dimensional stability, cross-dye pattern potential, at a very competitive price.[3]
Cellulose acetate fiber, one of the earliest synthetic fibers, is based on cotton or tree pulp cellulose (\"biopolymers\"). These \"cellulosic fibers\" have been replaced in many applications by cheaper petro-based fibers (nylon and polyester) in recent decades.[4]
Cellulose acetate and cellulose triacetate are mistakenly referred to as the same fiber; although they are similar, their chemical identities differ. Triacetate is known as a generic description or primary acetate containing no hydroxyl group. Acetate fiber is known as modified or secondary acetate having two or more hydroxyl groups. Triacetate fibers, although no longer produced in the United States, contain a higher ratio of acetate-to-cellulose than do acetate fibers.[1]
Cellulose acetate film, made from cellulose diacetate and later cellulose triacetate, was introduced in 1934 as a replacement for the cellulose nitrate film stock that had previously been standard. When exposed to heat or moisture, acids in the film base begin to deteriorate to an unusable state, releasing acetic acid with a characteristic vinegary smell, causing the process to be known as \"vinegar syndrome\". Acetate film stock is still used in some applications, such as camera negative for motion pictures. Since the 1980s, polyester film stock (sometimes referred to under Kodak's trade name \"ESTAR Base\") has become more commonplace, particularly for archival applications. Acetate film was also used as the base for magnetic tape, prior to the advent of polyester film.
Cellulose acetate magnetic tape was introduced by IBM in 1952 for use on their IBM 726 tape drive in the IBM 701 computer. It was much lighter and easier to handle than the metal tape introduced by UNIVAC in 1951 for use on their UNISERVO tape drive in the UNIVAC I computer. In 1956, cellulose acetate magnetic tape was replaced by the more stable PET film magnetic tape for use on their IBM 727 tape drive.
The Federal Trade Commission definition for acetate fiber is: \"A manufactured fiber in which the fiber-forming substance is cellulose acetate. Where not less than 92 percent of the hydroxyl groups are acetylated, the term triacetate may be used as a generic description of the fiber.\"
Acetate is derived from cellulose by initially deconstructing wood pulp into a purified fluffy white cellulose. To manufacture a good product, special qualities of pulps, such as dissolving pulps, are used. The uneven reactivity of cellulose presents a common problem affecting the quality of the cellulose acetate product. The cellulose is reacted with acetic acid and acetic anhydride in the presence of sulfuric acid. It is subjected to a controlled, partial hydrolysis to remove the sulfate and a sufficient number of acetate groups to give the product the desired properties. The anhydroglucose unit is the fundamental repeating structure of cellulose and has three hydroxyl groups which can react to form acetate esters. The most common form of cellulose acetate fiber has an acetate group on approximately two of every three hydroxyls. This cellulose diacetate is known as secondary acetate, or simply as \"acetate\".
After it is formed, cellulose acetate is dissolved in acetone, forming a viscous solution for extrusion through spinnerets (which resemble a shower head). As the filaments emerge, the solvent is evaporated in warm air via dry spinning, producing fine cellulose acetate fibers. 59ce067264
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