Chemistry:Linoleum
Linoleum is a floor covering made from materials such as solidified linseed oil (linoxyn), pine resin, ground cork dust, sawdust, and mineral fillers such as calcium carbonate, most commonly on a hessian or canvas backing. Pigments are often added to the materials to create the desired color finish. Due to the pigment being mixed directly into the linoleum cement, the finished color of the tile remains visible even after years of wear. In the past some of these pigments were iron oxide, red lead or lithopone.[1]
It gained popularity as a beautiful and easy to clean flooring option in the late 19th century and is still used today. Commercially, the material has been largely replaced by sheet vinyl flooring, a plastic alternative made of polyvinyl-chloride, though many still call it linoleum. This is mainly due to the fact that its plastic counterpart is less costly and much faster to produce.[2]
The finest linoleum floors, known as "inlaid", are extremely durable, and are made by joining and inlaying solid pieces of linoleum. Cheaper patterned linoleum comes in different grades or gauges, and is printed with thinner layers which are more prone to wear and tear. High-quality linoleum is flexible and thus can be used in buildings where a more rigid material (such as ceramic tile) would crack.
Chemistry
Linoleum in essence consists of two components, a polymerized organic compound and a collection of fillers, pigments, and catalysts. The polymerized precursors are rich in polyunsaturated fats, especially derivatives of linoleic acid and alpha-linolenic acid. Such fats are called drying oils because they "dry" (harden) upon exposure to the oxygen in air.[3] The drying process results in cross-linking of the fat molecules. This cross-linking process is often slow, thus catalysts and heat are applied to give a durable material. During this cross-linking, fillers and pigments are mixed with the resin.
Sustainability
Linoleum is a sustainable choice when looking for flooring options in comparison to many other plastic alternatives. It is created from multiple renewable resources that are non toxic and fully biodegradable, not to mention it is very durable and will last at least 20 years, if not longer if maintained correctly.[4]
This means that linoleum's ecological footprint is very small in comparison to many other material choices on the market. Linoleum is considered an environmentally friendly alternative to PVC as it is derived from renewable, natural, biodegradable material.[5] Many companies that manufacture linoleum sheets have environmental certifications such as some of the leading brands Artoleum and Marmoleum.[6][4]
Furthermore, off-cuts created during the manufacturing process are fully recyclable and can be ground or cut up and mixed into new batches of the linoleum cement.
One of the main flax sources for the linseed oil used in linoleum's manufacturing is Canada due to its annual crop abundance in the Canadian western prairies.[4]
History
Linoleum was invented by Englishman Frederick Walton.[7] In 1855, Walton happened to notice the rubbery, flexible skin of solidified linseed oil (linoxyn) that had formed on a can of oil-based paint and thought that it might form a substitute for India rubber. Raw linseed oil oxidizes very slowly, but Walton accelerated the process by heating it with lead acetate[clarification needed] and zinc sulfate. This made the oil form a resinous mass into which lengths of cheap cotton cloth were dipped until a thick coating formed. The coating was then scraped off and boiled with benzene or similar solvents to form a varnish. Walton initially planned to sell his varnish to the makers of water-repellent fabrics such as oilcloth, and received Patent No. 209 on 27 January 1860[8] for the process. However, his method had problems: the cotton cloth soon fell apart, and it took months to produce enough of the linoxyn. Little interest was shown in Walton's varnish. In addition, his first factory burned down, and he suffered from persistent and painful rashes.
Walton soon came up with an easier way to transfer the oil to the cotton sheets, by hanging them vertically and sprinkling the oil from above, and he tried mixing the linoxyn with sawdust and cork dust to make it less tacky. In 1863, he applied for a further patent, which read: "For these purposes canvas or other suitable strong fabrics are coated over on their upper surfaces with a composition of oxidized oil, cork dust, and gum or resin ... such surfaces being afterward printed, embossed, or otherwise ornamented. The back or under surfaces of such fabrics are coated with a coating of such oxidized oils, or oxidized oils and gum or resin, and by preference without an admixture of cork."
At first, Walton called his invention "Kampticon", which was deliberately close to Kamptulicon, the name of an existing floor covering, but he soon changed it to Linoleum, which he derived from the Latin words linum (flax) and oleum (oil).[9] In 1864, he established the Linoleum Manufacturing Company Ltd., with a factory at Staines, near London. The new product did not prove immediately popular, mainly due to intense competition from the makers of Kamptulicon and oilcloth. The company operated at a loss for its first five years, until Walton began an intensive advertising campaign and opened two shops in London for the exclusive sale of Linoleum. Walton's friend Jerimiah Clarke designed the linoleum patterns, typically with a Grecian urn motif around the borders.
Other inventors began their own experiments after Walton took out his patent, and in 1871, William Parnacott took out a patent for a method of producing linoxyn by blowing hot air into a tank of linseed oil for several hours, then cooling the material in trays. Unlike Walton's process, which took weeks, Parnacott's method took only a day or two, although the quality of the linoxyn was not as good. Despite this, many manufacturers opted to use the less expensive Parnacott process.
Walton soon faced competition from other manufacturers, including a company which bought the rights to Parnacott's process, and launched its own floor covering, which it named Corticine, from the Latin cortex (bark or rind). Corticine was mainly made of cork dust and linoxyn without a cloth backing, and became popular because it was cheaper than linoleum.
By 1869, Walton's factory in Staines, England was exporting to Europe and the United States. In 1877, the Scottish town of Kirkcaldy, in Fife, became the largest producer of linoleum in the world, with no fewer than six floor cloth manufacturers in the town, most notably Michael Nairn & Co., which had been producing floor cloth since 1847.
Other products devised by Walton included Linoleum Muralis in 1877, which became better known as Lincrusta. Essentially a highly durable linoleum wall covering, Lincrusta could be manufactured to resemble carved plaster or wood, or even leather. It was very successful, and inspired a much cheaper imitation, Anaglypta, originally devised by one of Walton's showroom managers.
Loss of trademark protection
When Frederick Walton named the flooring material linoleum, he was echoing the material composition of the product. Linoleum is derived from two Latin words, ‘linum’ (flax) and ‘oleum’ (oil).