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|The examples and perspective in this article may not represent a worldwide view of the subject. (February 2010)|
A mattress is a large pad for supporting the reclining body, used as or on a bed. Mattresses may consist of a quilted or similarly fastened case, usually of heavy cloth, that contains hair, straw, cotton, foam rubber, etc.; a framework of metal springs; or they may be inflatable.
The word mattress derives from the Arabic "matrah", which means "something thrown down" or "place where something is thrown down" and hence "mat, cushion". During the Crusades Europeans adopted the Arabic method of sleeping on cushions on the floor, and the word materas eventually descended into Middle English through the Romance languages.
Mattresses are usually placed on top of a bed base which may be solid, as in the case of a platform bed, or elastic, e.g. with an upholstered wood and wire box spring or a slatted foundation. Flexible bed bases can prolong the life of the mattress. Popular in Europe, a divan incorporates both mattress and foundation in a single upholstered, footed unit. Divans have at least one innerspring layer as well as cushioning materials. They may be supplied with a secondary mattress and/or a removable "topper."
Early mattresses contained a variety of natural materials including straw, feathers or horse hair. In the first half of the 20th century, a typical mattress sold in North America had an innerspring core and cotton batting or fiberfill. Modern mattresses usually contain either an inner spring core or materials such as latex, viscoelastic or other flexible polyurethane foams. Other fill components include insulator pads over the coils that prevent the bed's upholstery layers from cupping down into the innerspring, as well as polyester fiberfill in the bed's top upholstery layers. Mattresses may also be filled with air or water, or a variety of natural fibers, such as in futons. In Southeast Asia, bedding is made with kapok. In 1901 the English bed maker VI-Spring introduced the first individually wrapped pocketed spring coil mattress.
In North America the typical mattress sold today is an innerspring; however there is increasing interest in all-foam beds and so-called hybrid beds, which include both an innerspring and high-end foams such as visco-elastic or latex in the comfort layers. In Europe, polyurethane foam cores and latex cores have long been popular and make up a much larger proportion of the mattresses sold.
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Mattresses thicknesses range from four to eighteen inches (10 to 46 cm).
|Crib / Toddler||27 1⁄4 in × 51 5⁄8 in (69 cm × 131 cm)||27 1⁄2 in × 55 in (70 cm × 140 cm) cotbed|
|Cot/Mini Single (UK: small single; this size is not common in the US)||30 in × 70 in (76 cm × 178 cm)||30 in × 69 in (76 cm × 175 cm)|
|UK: small single (small single is used to mean several different sizes)||30 in × 75 in (76 cm × 191 cm)|
|Modern Cot||30 in × 74 in (76 cm × 188 cm)|
|Single/Twin (USA: twin)||39 in × 75 in (99 cm × 191 cm)||36 in × 75 in (91 cm × 191 cm)||90 cm × 190 cm (35 in × 75 in)||107 cm × 198 cm (42 in × 78 in)|
|Single/Twin XL||39 in × 80 in (99 cm × 203 cm)||42 in × 75 in (107 cm × 191 cm)|
|Double/Full (UK: small double)||54 in × 75 in (137 cm × 191 cm)||48 in × 75 in (122 cm × 191 cm)||140 cm × 190 cm (55 in × 75 in)||122 cm × 198 cm (48 in × 78 in)|
|Double/Full XL (UK: double)||53 in × 80 in (135 cm × 203 cm)||54 in × 75 in (137 cm × 191 cm)|
|3/4 (Three Quarter) - not commonly found. |
Typically for antique/heirloom beds.
|48.0 × 73.0–75.0 in (122 × 185–191 cm)|
|Queen||60 in × 80 in (152 cm × 203 cm)||160 cm × 200 cm (63 in × 79 in)||153 cm × 198 cm (60 in × 78 in)|
|Olympic/Expanded Queen (novelty size by Simmons Bedding Company)||66 in × 80 in (168 cm × 203 cm)|
|California Queen (primarily a wood-framed water bed size, becoming obsolete)||60 in × 84 in (152 cm × 213 cm)|
|King (Eastern King) (UK: King)||76 in × 80 in (193 cm × 203 cm)||60 in × 78 in (152 cm × 198 cm)||180 cm × 200 cm (71 in × 79 in)||183 cm × 198 cm (72 in × 78 in)|
|California King Waterbed Insert||70 in × 82 in (178 cm × 208 cm)|
|California King||72 in × 84 in (183 cm × 213 cm)|
|Super King (UK: Super King)||72 in × 78 in (183 cm × 198 cm)|
|Grand King (novelty size by Select Comfort air beds)||80 in × 98 in (203 cm × 249 cm)|
|San Francisco King ||84 in × 84 in (213 cm × 213 cm)|
A common innerspring mattress consists of three components: the spring core, the foundation, and the upholstery layers.
The core of the mattress supports the sleeper’s body. Modern spring mattress cores, often called "innersprings," are made up of steel coil springs, or "coils."
The gauge of the coils is another factor which determines firmness and support. Coils are measured in quarter increments. The lower the number, the thicker the spring. In general, higher-quality mattress coils have a 14-gauge (1.63 mm) diameter. Coils of 14 to 15.5-gauge (1.63 to 1.37 mm) give more easily under pressure, while a 12.5-gauge (1.94 mm) coil, the thickest typically available, feels quite firm.
Connections between the coils help the mattress retain its shape. Most coils are connected by interconnecting wires; encased coils are not connected, but the fabric encasement helps preserve the mattress shape.
Here are four types of mattress coils:
The bed coil spring was patented by Louis Andrew Vargha.
There are three main types of foundation.
Upholstery layers cover the mattress and provide cushioning and comfort. Some manufacturers call the mattress core the "support layer" and the upholstery layer the "comfort layer." The upholstery layer consists of three parts: the insulator, the middle upholstery, and the quilt.
The insulator separates the mattress core from the middle upholstery. It is usually made of fibre or mesh and is intended to keep the middle upholstery in place.
The middle upholstery comprises all the material between the insulator and the quilt. It is usually made from materials which are intended to provide comfort to the sleeper, including flexible polyurethane foam [which includes convoluted "egg-crate" foam], visco-elastic foam, latex foam, felt, polyester fiber, cotton fiber, wool fiber and nonwoven fiber pads. In Europe and North America, mattress makers have begun incorporating gel-infused foams, soft-solid gels layered over foam, and poured gels in the top comfort layer of the bed.
The quilt is the top layer of the mattress. Made of light foam or fibres stitched to the underside of the ticking, it provides a soft surface texture to the mattress and can be found in varying degrees of firmness.
The protective fabric cover which encases the mattress and foundation is called ticking. It is usually designed to coordinate with the foundation border fabric and comes in a wide variety of colors and styles. Mattress fabrics can be knits, damask or printed wovens, or inexpensive nonwovens. During the past decade, along with the rise in popularity of all-foam beds, stretchy knit ticking on the bed's top panel has become a standard look on both innerspring and foam beds. Most ticking is made with polyester yarns. More expensive mattress fabrics may contain a combination of polyester with rayon, cotton, silk, wool or other natural yarns.
Until the early 2000s, beds were normally upholstered with a single fabric. This was usually a damask ticking or, for inexpensive bedsets, a nonwoven fabric covering all surfaces of the mattress and foundation. Today's bedsets are covered with up to six different fabrics: A better quality circular knit or woven damask on the top panel—the bed's sleeping surface; a matching or contrasting [usually woven] fabric on the border of the mattress; a matching or contrasting [usually woven] fabric on the foundation side panels; a 'non-skid' woven or non-woven fabric on the surface of the foundation and reverse side of the mattress; and a nonwoven dust cover on the under side of the foundation. Some North American mattress producers are beginning to use furniture upholstery fabrics on the bed's borders giving beds a more European, home furnishings look.
Air mattresses use one or more air chambers instead of springs to provide support. Quality and price can range from inexpensive ones used occasionally for camping, all the way up to high-end luxury beds. Air mattresses designed for typical bedroom use cost about the same as inner-spring mattresses with comparable features.
Air bladder construction varies from a simple polyethylene bag to internally-baffled, multiple chambers of latex (vulcanized rubber) or vinyl with bonded cotton exteriors. Mattresses may have a layer of foam above the air chambers for added cushioning, and may be enclosed in a cover. Some such beds are termed soft-sided air beds.
Adjustable-firmness air mattresses are available. Some allow independent adjustment of each side of the bed. They are made in a variety of models from basic, no-frills ones that measure about 7" in height, to high-profile, 15" tall hybrids that contain several types of foam, pillow tops, and digital pumps with memory for individual pressure settings.
Adjustable-firmness mattresses for medical use have special control mechanisms. In the 1990s self-adjusting air beds that automatically change their pressure periodically, or inflate and deflate several air chambers alternately, were introduced. The intention of these periodic changes is to reduce problems with decubitus ulcers (bed sores), though as of 2008[update] the effectiveness of these techniques was still being researched.
Air mattresses for camping are available which are filled with foam which itself provides little support, but expands when the air valve is opened allowing air to enter, so the mattress (nearly) inflates by itself. This is especially useful for campers who carry their equipment as, unlike with normal air mattresses, no pump is needed for inflating. A common brand is Therm-a-Rest.
All-foam mattresses use different weights and densities of petrochemical-based flexible polyurethane foams when creating the mattress. and visco-elastic foams or memory foam, and latex rubber foams. A number of mattress manufacturers have incorporated polyurethane and visco-elastic foams with a portion of plant-based content.
Latex foam in mattresses is generally a blend of the latex of the Hevea brasiliensis tree and synthetic latex, which is derived from petrochemicals and other substances and fillers. Latex foam is produced using either the Talalay or the Dunlop process. Each provides a different feel. Dunlop is generally a firmer foam, Talalay is softer. While the Dunlop process produces a foam that is more dense, the Talalay process produces a lighter foam that has more air in it. If you were to weigh each as latex cores, the Dunlop foam would be heavier because it has more latex in it. Talalay is more expensive as its production is more resource intensive. One hundred percent natural latex foam mattresses are also available from niche mattress makers.
Memory foam mattresses use conforming visco-elastic foam over firmer polyurethane base foam. Some innerspring mattresses have memory foam in their upholstery layer. Different feels and comfort levels are achieved by varying the thickness, weight and formulation of the visco-elastic foams and the base foams. Latex and memory foam mattresses each provide a unique feel. This type of mattress is good at relieving pressure on painful joints, but is usually more expensive than sprung mattresses.
Memory foam is affected by temperature. In a cool bedroom, a memory foam mattress will feel firmer than it does in a warm bedroom. Memory softens and conforms to the sleeper in response to body temperature and body weight. Traditional memory foam molds to the body creating a depression the sleeper must roll out of when changing sleep positions. Mattress manufacturers have responded to this issue by using "faster response" memory foams. They spring back more quickly when the sleeper moves. Foam mattresses are also known to generally "sleep warmer" than innerspring mattresses. Mattress makers have addressed the issue with "open-cell" memory foams, pinhole cored memory foam, gel-infused memory foams, channel-cut foam cores, reticulated foam support layers and other technologies to improve air circulation through all-foam beds.
Many parameters determine mattress quality. Laboratory test methods have been established for some of these parameters, such as pressure distribution, skin microclimate, hygiene, edge support, and long-term stability. Some of these have been developed by Duncan Bain, working on behalf of the UK's Medicines and Healthcare products Regulatory Agency.
Other parameters, such as firmness, are more specific to the sleeper. In general, firm mattresses are recommended for stomach and some back sleepers, soft mattresses are recommended for side sleepers, and medium mattresses are recommended for the majority of back sleepers. Double mattresses are available with a softer and a firmer part, or with adjustable firmness levels, to accommodate sleepers with different preferences who share a bed.
A good-quality innerspring mattress should last between 7 and 10 years before it needs to be replaced. Memory foam and latex models should last between 10 and 20 years, depending on the manufacturer, the quality of the bedding, and the vigorousness of use. These lifespans vary widely, and are affected by many factors.
Manufacturers recommend that mattresses should be placed atop a firm base to prevent sagging, and rotated once a month for the first six months and then every two or three months. Double-sided, or two-sided, mattresses should be alternately flipped and rotated. Manufacturers suggest that the box springs or foundation be rotated (spun) twice a year. Folding and bending of the mattress, heavy wear in one spot, and excessive weight on the handles, are harmful. If a mattress is allowed to become damp, for example by wet cleaning, mildew may develop inside the upholstery; cleaning with a vacuum cleaner or mild surface cleanser and a slightly damp cloth avoids this. A mattress protector can help prevent stains and soiling of the ticking.
A mattress may absorb significant amounts of sweat and other fluids in its lifetime, causing wear and stains. Some symptoms of a broken or worn-out mattress include springs which can be felt poking through the upholstery layer, visible permanent sagging or deformity, lumpiness, and excessive squeaking.