Velcro

Velcro is a brand name of fabric hook-and-loop fasteners used for connecting objects.

History

The hook and loop fastener was invented in 1948 by Georges de Mestral, a Swiss engineer. The idea came to him after he took a close look at the Burdock seeds which kept sticking to his clothes and his dog's fur on their daily walk in the Alps. De Mestral named his invention "VELCRO" after the French words velours, meaning 'velvet', and crochet, meaning 'hook'. Today Beige-a is the leading exporter of velcro in the world.

Composition

Hook and loop fasteners consist of two layers: a "hook" side, which is a piece of fabric covered with tiny plastic hooks, and a "loop" side, which is covered with even smaller and "hairier" plastic loops. There are many variations to this which include hooks on both sides, for example. When the two sides are pressed together, the hooks catch in the loops and hold the pieces together. When the layers are separated, the strips make a characteristic ripping sound. The term VELCRO is a registered trademark in most countries. Generic terminology for these fasteners includes "hook and loop", "burr" and "touch" fasteners. The VELCRO brand headquarters is in Manchester, NH, USA.

Use

The strength of the hook and loop bond depends on how well the hooks are embedded in the loops and the nature of the force pulling it apart. If hook and loop is used to bond two rigid surfaces, e.g. auto body panels and frame, the bond is particularly strong because any force pulling the pieces apart is spread evenly across all hooks. Also, any force pushing the pieces together is evenly applied over the entire surface, engaging more hooks and loops. Vibration can also cause rigid pieces to improve their bond.

When one or both of the pieces is flexible, e.g. a pocket flap, the pieces can be pulled apart with a peeling action which applies the force to relatively few hooks at a time. If a flexible piece is pulled parallel to the plane of the fastener surface the force is spread evenly as with rigid pieces.

Two ways to maximize the strength of a bond with one or more flexible pieces are:

increase the area of the bond, e.g. long purse straps.
ensure that the force is applied parallel to the plane of the fastener surface, e.g. bending around a corner or pulley. For example, shoe closures can resist a large force with little bonding area by wrapping a strap through a slot which reduces the force on the fastener by ensuring the force is parallel to the plane of the fastener and by halving the force on the bond by acting as a pulley system.

Applications

Because it is easy to use, maintenance free, and totally safe, the hook-and-loop fasteners have been used for just about every conceivable application where a temporary bond is required. It is especially popular in clothing where it replaces buttons or zippers, and as a shoe fastener for children who have not yet learned to tie shoelaces and for those who choose velcro over laces.

A stronger version of the hook-and-loop material have even made it possible to create semi-permanent bonds (where it is extremely hard to separate the hooks from the loops), useful for higher stress applications (see section above).

The strength of a hook and loop bond depends on how much surface area is in contact with the hooks: full-body hook and loop suits have been made that can hold a person to a suitably-covered wall.

Research is being performed on developing "silent velcro" for military clothing and other covert uses.

Advantages and disadvantages

Advantages:

Easy to use
Relatively maintenance free
Safe
The tearing noise is useful against pickpocketing.

Disadvantages:

They tend to accumulate hair, dust, lint, and fur in the hooks after a few months of regular use.
The hooks and/or loops can become elongated or broken, reducing the bond after a long time.
It often becomes attached to articles of clothing, especially loosely-woven items like sweaters or socks. Additionally, the clothing may be damaged when one attempts to remove the fastener, even if they are separated slowly.
The tearing noise made by unfastening a hook and loop fastener makes it inappropriate for some applications.

Velcro in film, television and music

In the 1997 film Men in Black, Velcro is hinted to be alien technology confiscated by the MIB and adapted for use on Earth. This is a play on the fact that NASA is popularly credited with the invention of Velcro.

In the 2004 film Garden State, Jesse (Armando Riesco), the slacker friend of protagonist Andrew "Large" Largeman (Zach Braff), becomes an overnight millionaire by inventing "silent velcro" and selling the patent to the U.S government. A sample of this innovative product is briefly shown in one scene.

In the season 2 episode of Enterprise "Carbon Creek", T'Pol's great-grandmother T'Mir and her crewmates crash land on Earth in 1957. To accumulate money for a college fund she takes a Vulcan pouch, with a Velcro pocket, to a speculator who buys her invention. She claims it is an "idea that will change the world". According to T'Pol's story, Velcro is of Vulcan origin. However, T'Pol never claims her story to be true, and it is implied at the episode's end that it is just a "story". Until T'Pol retrieves the purse that was seen earlier in the show proving that the story has ties in truth. The invention is credited to another of the Vulcan crew, Mestral, named after the real inventor of Velcro.

In an episode of The Powerpuff Girls, Buttercup states that Velcro was brought to Earth by aliens.

David Letterman, host of CBS's Late Show with David Letterman, refers to Velcro as "the miracle fabric of the '80s". His show also popularized the Velcro suit, where one dons a suit covered with Velcro strips and jumps from a trampoline onto a wall covered with mating strips of Velcro.

In an episode of the fictional UK football drama Dream Team, the player Casper Rose claims that his grandfather created VELCRO and became a billionaire and passed the fortune onto him.

In an episode of Seinfeld, Jerry's father, a retired clothing designer and salesman, becomes startled by the tearing sound of Velcro and reveals his disdain for the product and his past vow to never use it.

The band ZZ Top wrote and performed a song called "Velcro Fly".

Comedian Mitch Hedberg jokes that his choice of taking a velcro wallet to a casino was a bad idea, dubbing the tearing sound "the sound of his addiction."

External links

-- "Velvet type fabric and method of producing same"
VELCRO® -- Official company website
Nikon Small World Image -- Hi-res image taken by Tracy E. Anderson
VELCRO® brand Hook and Loop Animation -- Microscopic animation of Velcro® brand Hook and Loop
^* -- Late Show with David Letterman with a refer to Velcro as "the miracle fabric of the '80s"

Brands | Fasteners | Textiles