Aside from protective clothing, the fibre is found in a variety of products, including aeroplanes, mobile phones, and sailboats. Image source, AP. Kwolek invented a liquid crystalline solution that could be spun into the fabric now known as Kevlar. The Kevlar fibre is used by millions of people around the world, like these regular house gloves. One of the first attempts was creation of Bomber's Shield for pilots who were very susceptible to bullets and shrapnel that could pierce and ricochet inside the planes.
Several types of infantry armors were also introduced, but slow deployment and small scale production meant that vast majority of wounded and killed soldiers who could benefit from such armor pieces did not receive them. All combat armors created in that time were very heavy and prevented soldiers to move fast. Lighter examples of armors were strangely popularized by American gangsters in s and s, whose cotton and silk vests could stop the bullets from very large variety of then most popular guns but not most powerful.
Waterproofing and additional layers of fabric were added to the Kevlar to make the vests more durable and wearable. The National Institute of Justice tested versions of Kevlar vests for several years, and found that the vests could stop the most common lead bullets: 38 Specials and 22 Long Rifle Bullets. In , scientists came to the conclusion that Kevlar was bullet-resistant, wearable and light enough for police officers to wear full-time.
The funny thing was that bulletproof vests had already become commercially available, even before the National Institute of Justice published these claims.
Since that time bulletproof vests have improved. Currently, a level IIIA bulletproof vest weighs approximately 5. As civilizations became more advanced, wooden shields and then metal shields came into use. Eventually, metal was also used as body armor, what we now refer to as the suit of armor associated with the knights of the Middle Ages. However, with the invention of firearms around , metal body armor became ineffective. Then only real protection available against firearms were stone walls or natural barriers such as rocks, trees, and ditches.
One of the first recorded instances of the use of soft body armor was by the medieval Japanese, who used armor manufactured from silk. It was not until the late 19th century that the first use of soft body armor in the United States was recorded. At that time, the military explored the possibility of using soft body armor manufactured from silk. The project even attracted congressional attention after the assassination of President William McKinley in While the garments were shown to be effective against low-velocity bullets, those traveling at feet per second or less, they did not offer protection against the new generation of handgun ammunition being introduced at that time.
Ammunition that traveled at velocities of more than feet per second. This, along with the prohibitive cost of silk made the concept unacceptable. Silk armor of this type was said to have been worn by Archduke Francis Ferdinand of Austria when he was killed by a shot to the head, thereby precipitating World War I.
The U. Patent and Trademark Office lists records dating back to for various designs of bulletproof vests and body armor type garments. One of the first documented instances where such a garment was demonstrated for use by law enforcement officers was detailed in the April 2, , edition of the Washington, D. The next generation of the anti-ballistic bullet proof vest was the World War II "flak jacket" made from ballistic nylon.
The flak jacket provided protection primarily from ammunition fragments and was ineffective against most pistol and rifle threats. Flak jackets were also very cumbersome and bulky. It would not be until the late s that new fibers were discovered that made today's modern generation of cancelable body armor possible.
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