Blowdryer
Encyclopedia
A blowdryer or hairdryer is an electromechanical device designed to blow cool or hot air over wet or damp hair
Hair
Hair is a filamentous biomaterial, that grows from follicles found in the dermis. Found exclusively in mammals, hair is one of the defining characteristics of the mammalian class....

, in order to accelerate the evaporation
Evaporation
Evaporation is a type of vaporization of a liquid that occurs only on the surface of a liquid. The other type of vaporization is boiling, which, instead, occurs on the entire mass of the liquid....

 of water particles and dry the hair. Blowdryers allow to better control the shape and style of hair, by accelerating and controlling the formation of temporary hydrogen bond
Hydrogen bond
A hydrogen bond is the attractive interaction of a hydrogen atom with an electronegative atom, such as nitrogen, oxygen or fluorine, that comes from another molecule or chemical group. The hydrogen must be covalently bonded to another electronegative atom to create the bond...

s inside each strand. These hydrogen bonds are very powerful (allowing for stronger hair shaping than even the sulfur bonds formed by permanent waving products
Permanent wave
A permanent wave, commonly called a perm, involves the use of chemicals to break and reform the bonds of the hair. The hair is washed and wrapped on a perm rod and waving lotion is applied with a base. This solution creates a chemical reaction that softens the inner structure of the hair by...

), but are temporary and extremely vulnerable to humidity
Humidity
Humidity is a term for the amount of water vapor in the air, and can refer to any one of several measurements of humidity. Formally, humid air is not "moist air" but a mixture of water vapor and other constituents of air, and humidity is defined in terms of the water content of this mixture,...

. They disappear with a single washing of the hair.

Hairstyle
Hairstyle
A hairstyle, hairdo, or haircut refers to the styling of hair, usually on the human head. The fashioning of hair can be considered an aspect of personal grooming, fashion, and cosmetics, although practical, cultural, and popular considerations also influence some hairstyles.-History of...

s using blowdryers usually have volume and discipline, which can be further improved by the use of styling products and hairbrush
Hairbrush
A hairbrush is a stick brush with rigid or soft bristles used in hair care for smoothing, styling, and detangling human hair, or for grooming an animal's fur.-Human use:...

es during drying to add tension, hold and lift.

Blowdryers were invented
Invention
An invention is a novel composition, device, or process. An invention may be derived from a pre-existing model or idea, or it could be independently conceived, in which case it may be a radical breakthrough. In addition, there is cultural invention, which is an innovative set of useful social...

 around the end of the 19th century. The first model was created by Alexander F. Godefoy in his salon in France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

 in 1890. The handheld, household hair-dryer first appeared in 1920. Blowdryers are used both in the beauty salon
Beauty salon
A beauty salon or beauty parlor is an establishment dealing with cosmetic treatments for men and women...

 by professional stylists, and in the average household by consumers
Consumer
Consumer is a broad label for any individuals or households that use goods generated within the economy. The concept of a consumer occurs in different contexts, so that the usage and significance of the term may vary.-Economics and marketing:...

.

Function

Most models use coils of wire that have a high electric resistivity
Resistivity
Electrical resistivity is a measure of how strongly a material opposes the flow of electric current. A low resistivity indicates a material that readily allows the movement of electric charge. The SI unit of electrical resistivity is the ohm metre...

 and heat rapidly with an electric current. A fan usually blows ambient air past the hot coils resulting in heated air effective for drying. The heating element
Heating element
A heating element converts electricity into heat through the process of Joule heating. Electric current through the element encounters resistance, resulting in heating of the element....

 in most hairdryers is a bare, coiled nichrome wire that is wrapped around insulating mica heating boards. Nichrome wire is used in heating elements, because of two important properties: it is a poor conductor of electricity and it does not oxidize when heated.

In terms of modern models, a survey of stores in 2007 showed that most hair dryers have ceramic
Ceramic
A ceramic is an inorganic, nonmetallic solid prepared by the action of heat and subsequent cooling. Ceramic materials may have a crystalline or partly crystalline structure, or may be amorphous...

 heating element
Heating element
A heating element converts electricity into heat through the process of Joule heating. Electric current through the element encounters resistance, resulting in heating of the element....

s (like ceramic heaters)—because of their “instant heat” capability. This means that it takes less time for the dryers to heat up, and thus it takes a lot less time for the hair to dry.

Many of these hair dryers have “cool shot” buttons which turn off the heater and just blow room temperature air while the button is pressed. This function is useful in helping to maintain the hairstyle by setting it. The cold air also reduces frizz and can help to bolster the shine in the hair.

Many also feature “ionic” operation, to reduce the amount of static electricity
Static electricity
Static electricity refers to the build-up of electric charge on the surface of objects. The static charges remain on an object until they either bleed off to ground or are quickly neutralized by a discharge. Static electricity can be contrasted with current electricity, which can be delivered...

 build-up in the hair. Manufacturers also claim this makes the hair “smoother.” Some stylists today consider the introduction of ionic technology to be one of the most important advances in the beauty industry.

Hair dryers are available with different attachments, including a diffuser, an airflow concentrator, and a comb nozzle attachment . A diffuser is an attachment that is used on hair that is fine, colored, permed or naturally curly. It works by diffusing the heat so that the hair dries more slowly at a cooler temperature. This makes it so that the hair is less likely to frizz and it gives the hair more volume. An airflow concentrator does the exact opposite of a diffuser. It makes the end of the blowdryer more narrow and thus helps to concentrate the heat into one spot in order to make it dry rapidly. The comb nozzle attachment is the same as the airflow concentrator, but it ends with comb-like teeth so that the user can dry the hair using just the dryer without a brush or comb.

History

Before the invention of the hairdryer, it was actually common for men and women to dry their hair using a vacuum cleaner. In fact, the original model of hairdryer was invented in 1890 by Alexandre Goldefroy by taking inspiration from the vacuum cleaner. Alexandre invented it for usage in his hair salon in France and it was not portable or handheld, but instead could only be used by having the woman sit underneath it. However, it was not until the 1920s that the hairdryer began to go on the market in handheld form. This was due to innovations by US Racine Universal Motor Company and the Hamilton Beach Co. that allowed the hairdryer to be handheld. Even in the 1920s the new hairdryers were often heavy, weighing in at approximately 2 lbs, and difficult to use. They also had many instances of overheating and electrocution. It was also only capable of using 100 watts so it took a lot longer to dry hair (the average hairdryer today can use up to 2000 watts of heat).

Since the 1920s, development of the hairdryer has mainly focused on improving the wattage and superficial exterior and material changes. In fact, the mechanism of the hairdryer has not had any significant changes since its inception. One of the more important changes for the hairdryer is having the materials change to plastic so that it is more lightweight. This really caught on in the 1960s with the introduction of better electrical motors and the improvement of plastics. Another important change happened in 1954 when GEC changed the design of the dryer to move the motor inside the casing. Also, including safety mechanisms in them has been important, especially since Consumer Product Safety Commission set up guidelines in the 1970s that hairdryers had to meet in order to be considered safe to manufacture. Since 1991 the CPSC has mandated by US law that all dryers must use a ground fault circuit interrupter so that it cannot electrocute a person if it gets wet. By the year 2000 deaths by blowdryers had dropped to less than four people a year, a stark difference to the hundreds of cases of electrocution accidents during the mid-twentieth century. In terms of positive health, this type of hairdryer has also been cited as an effective treatment for head lice. Overall, the size, weight, noise, and appearance of the hairdryer has dramatically changed from the heavy bulky noisy contraptions of the early part of the twentieth century, to the streamlined plastic that people are used to today.

There are two other major types of blowdryers other than the hand held. These are the bonnet hairdryer and the rigid-hood hairdryer. The bonnet hairdryer was introduced to consumers in 1951. This type of dryer worked by having the dryer, usually in a small portable box, connected to a tube that went into a bonnet with holes in it that could be placed on top of a persons head. This worked by giving an even amount of heat to the whole head at once. The 50s also saw the introduction of the rigid-hood hair dryer which is the type most frequently seen in salons, and it had a hard plastic helmet that goes over the head. This dryer works similarly to the bonnet hairdryer but at a much higher wattage.
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