Although Bakelite was being produced since , its application as a varnish before does not seem probable. Recent examination of the collection revealed that the most fragile pieces were covered by a similar dark brown layer that could be presumed to be Bakelite; objects of marble or other polishable stones had not undergone consolidation treatment.
The spectrum exactly corresponded with both the Bakelite reference and the angle capital spectra Fig. Although more coating samples must be analysed, it can be supposed with certainty that Bakelite was used for the consolidation of objects from this collection.
Figure 4. If the 'treatment for decay' mentioned in the record refers to consolidation with Bakelite, this predates the earliest recorded such usage by at least six years. The detection of Bakelite on stone objects reveals a previously unknown application of this resin. For over two decades Bakelite was regarded as an excellent conservation material and its identification on stone objects in the Victoria and Albert Museum shows that it could have been used as a consolidant in other types of objects as well.
Conservators frequently come across old conservation materials and Bakelite must be considered as such from now on. Further study is necessary to determine the extent and implications of Bakelite's past use.
It is hoped that this brief overview will serve as a useful introduction to the use of Bakelite as a stone consolidant.
Reboul, P. Meikle, J. Horie, C. Case, E. Nichols, H. Howie, F. We have launched a new website and are reviewing this page. My Website. Bakelite - the Material of a Thousand Uses Some links from this site lead to third parties who pay us a commission if you buy something.
Bakelite Bowl with Nutcracker. Rare Caravan. Photo by K. Wikimedia Commons. Collection of Green Necklaces. Australian Duperite Green Lamp.
Art Deco from Decolish. Enjoy this page? Please pay it forward. Here's how Would you prefer to share this page with others by linking to it? Click on the HTML link code below. People bought Bakelite jewelry boxes, lamps, desk sets, clocks, radios, telephones, kitchenware, tableware, and a variety of game pieces such as chess sets, billiard balls, and poker chips.
Bakelite ushered in a new era of attractive, affordable, convenient consumer goods, making it possible for a broad range of consumers to enjoy products that previously had been inaccessible. Bakelite made perhaps its largest stamp on the world of fashion. Bakelite jewelry became immensely popular in the s as an affordable and attractive replacement for other materials.
It came in several colors, including translucent and marbled shades by the s. Bakelite jewelry from this era often had striking patterns, such as polka dots and chevrons, and it could be carved into intricate shapes. Bakelite and Galalith before it introduced plastics to the fashion world, to be followed by nylon, polyester, spandex, and more. Many 19th century manufacturers modified colloids and natural polymers to form new materials.
In , the American inventor John Wesley Hyatt used chemically modified cellulose to produce an astonishing new product called Celluloid, a plastic that was used for everything from hair combs to silent-movie film. By , Count Hilaire de Chardonnet was marketing the first synthetic textile, Chardonnet silk, made by spinning strands of cellulose nitrate into artificial fiber. These and other early plastics were made from existing materials.
The next step—the creation of completely synthetic plastic—was still to come. During the Victorian era, it was fashionable for wealthy gentlemen to own a billiard table and a set of billiard balls crafted of the finest and most perfect ivory.
But 19th century hunters had virtually decimated the elephant herds of Africa and India, the source of ivory. They never received the money. But they did change history — by inventing celluloid, one of the world's first plastics. Celluloid not only resembled ivory, it had astonishing properties: at normal temperatures, it was a permanent, hard solid; when heated, it became soft and could be molded or rolled into sheets.
It soon became the material of choice for billiard balls and dozens of other products. The Hyatts made celluloid by applying heat and pressure to a mix of cellulose nitrate and camphor; it was thus a plastic made by modifying natural materials. More than 40 years were to pass before the invention of the first wholly synthetic plastic.
By , the invention of Velox photographic paper had already made Leo Baekeland a wealthy man. At his Snug Rock estate in Yonkers, New York, he maintained a home laboratory where he and his assistant, Nathaniel Thurlow, involved themselves in a variety of projects.
Like other scientists of their day, Baekeland and Thurlow understood the potential of phenol-formaldehyde resins. The chemical literature included reports written decades earlier by the German chemist Adolf von Baeyer and by his student, Werner Kleeberg.
Von Baeyer had reported that when he mixed phenol, a common disinfectant, with formaldehyde, it formed a hard, insoluble material that ruined his laboratory equipment, because once formed, it could not be removed. Kleeburg reported a similar experience, describing the substance he produced as a hard amorphous mass, infusible and insoluble and thus of little use.
In , German chemist Adolf Luft patented a resin made by modifying Kleeburg's composition in the hope that it could compete commercially with celluloid. At least seven other scientists tried phenol and formaldehyde combinations in their attempt to create a commercially viable plastic molding compound. But no one was able to create a useful product. Hoping to capitalize on shortages of naturally occurring shellac—used to insulate electrical cables in the early years of the 20th century—Baekeland and Thurlow, as well as several other investigators, were experimenting with soluble resins.
Shellac was made from a resin secreted by the East Asian lac bug; it was harvested by the labor-intensive process of scraping the hardened deposits from the trees these insects inhabited.
Eventually, they developed a phenol-formaldehyde shellac called Novolak, but it was not a commercial success. By the early summer of , Baekeland changed his focus from trying to create a wood coating to trying to strengthen wood by actually impregnating it with a synthetic resin.
On June 18, , Baekeland began a new laboratory notebook now in the Archives Center of the Smithsonian's National Museum of American History documenting the results of tests in which he applied a phenol and formaldehyde mixture to various pieces of wood. An entry made the following day states:. All these tests were conducted in concentrated horizontal digester and the apparatus was reasonably tight.
Yet the surface of the blocks of wood does not feel hard although a small part of gum that has oozed out is very hard. In order to determine in how far this is possible I have heated in sealed tubes a portion of this liquid so as to determine whether there is a further separation of H 2 O or whether this is simply a solution of the hard gum in excess of phenol, then by simple open air evaporation I shall be able to accomplish hardening while I shall not succeed in closed sealed tubes.
I have also heated an open tube rammed with a mixture of asbestos fiber and liquid. Also a sealed tube rammed with mixture of asbestos fiber and liquid. I found tube broken perhaps in irregular expansion but the reactions seems to have been satisfactory because the resulting stick was very hard and below where there was some unmixed liquid A there was an end?
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