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Paper Knife
The terms paper knife and letter opener are often used interchangeably to refer to a knife-like desktop tool. In truth, they are actually for different functions and were in use at different times. Paper knives are used for cutting open the pages of hand-produced books where the folding of printed sheets creates some closed edges that require severing of the paper before reading. Letter openers "evolved" from paper knives into longer, blunter blades for the sole purpose of opening envelopes. Paper knives are no longer in common use, except perhaps by antiques enthusiasts. An electric version of a letter opener is also available, which uses motors to slide the envelopes across a blade, and is also able to handle increased numbers of envelopes, but the blade can slice into the contents of the envelope and damage them. Letter openers may be designed from wood, metals, such as stainless steel, silver, or pewter, plastic, ivory, or a combination of materials. Often the style of the ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bakelite Letter Opener
Polyoxybenzylmethylenglycolanhydride, better known as Bakelite ( ), is a thermosetting phenol formaldehyde resin, formed from a condensation reaction of phenol with formaldehyde. The first plastic made from synthetic components, it was developed by Leo Baekeland in Yonkers, New York in 1907, and patented on December 7, 1909 (). Because of its electrical nonconductivity and heat-resistant properties, it became a great commercial success. It was used in electrical insulators, radio and telephone casings, and such diverse products as kitchenware, jewelry, pipe stems, children's toys, and firearms. The "retro" appeal of old Bakelite products has made them collectible. The creation of a synthetic plastic was revolutionary for the chemical industry, which at the time made most of its income from cloth dyes and explosives. Bakelite's commercial success inspired the industry to develop other synthetic plastics. In recognition of its significance as the world's first commercial syntheti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
