Mattress

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Two-sided, innerspring pillow-top mattress on box-spring foundation. Woven damask cover. (Manufacturer: Shifman Mattress)

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.[1]

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.[2]

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[citation needed]. Popular in Europe, a divan[3] 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.[4]

History[edit]

Photo on a 1940 USDA circular promoting home production of cotton mattresses
  • Neolithic period: The mattress and bed are invented. Beds are raised off the ground to avoid drafts, dirt, and pests. The first mattress probably consisted of a pile of leaves, grass, or possibly straw, with animal skins over it.
  • 3600 B.C.: Beds made of goatskins filled with water are used in Persia.
  • 3400 B.C.: Egyptians sleep on palm boughs heaped in the corners of their homes.
  • 200 B.C.: Mattresses in Ancient Rome consist of bags of cloth stuffed with reeds, hay, or wool; the wealthy use feather stuffing.
  • 15th century: During the Renaissance, mattresses are made of pea shucks, straw, or sometimes feathers, stuffed into coarse ticks, and covered with velvets and brocades.
  • 16th and 17th centuries: Mattresses are stuffed with straw or down and placed atop a bed consisting of a timber frame with support latticeworks of rope or leather.
  • Early 18th century: Mattresses are stuffed with cotton or wool.
  • Mid 18th century: Mattress covers begin to be made of quality linen or cotton. The mattress cane box is shaped or bordered, and fillings include natural fibers such as coconut fibre, cotton, wool, and horsehair. The mattress is tufted or buttoned to attach the stuffing to the cover and the edges are stitched.
  • Late 19th century: The box-spring is invented to distribute weight and act as a shock absorber, thereby lengthening the life of an innerspring mattress.
  • 1926: Dunlop introduced a technology to produce vulcanized rubber latex foam. Similar foams still are used in latex mattresses and pillows (hence the name Dunlopillo). Initially it was only sold to British royalty.
  • 1930s: Innerspring mattresses and upholstered foundations become widely used, and artificial fillers become common. Encased coil spring mattresses, which consist of individual springs sewn into linked fabric bags, are introduced.
  • 1940s: Air mattresses constructed of vulcanized rubber-coated fabric are introduced.
  • 1960s: The modern waterbed is introduced and gains its first widespread use. Adjustable beds gain popularity. The California king size bed is introduced.[5]
  • 1970s: NASA invents material that later becomes known as memory foam.[6]
  • 1970s: A more advanced technology to produce synthetic foam rubber mattresses and pillows enabled factories to mass-market latex foam and reduce the consumption of natural rubber latex.
  • 1992: Tempur-Pedic introduces a mattress made from memory foam.
  • 1992: Fibrelux introduces a mattress made from rubberized coir.
  • 2000: Simmons Bedding Co. invents the "no-flip" mattress by removing the padding on one side of the mattress, a construction style that has since been adopted by most North American mattress manufacturers.[7]

Mattress dimensions[edit]

Mattresses thicknesses range from four to eighteen inches (10 to 46 cm).

International Mattress Sizes [8]
Denomination U.S./Canada
inches (cm)
U.K.
inches (cm)
E.U. (Continental)
cm (inches)
Asia (Thailand)
cm (inches)
Crib / Toddler 27 14 in × 51 58 in (69 cm × 131 cm) 27 12 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 [9] 84 in × 84 in (213 cm × 213 cm)


Types of mattress[edit]

Innerspring[edit]

A common innerspring mattress consists of three components: the spring core, the foundation, and the upholstery layers.[10]

Core[edit]

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:

  • Bonnell coils are the oldest and most common. First adapted from buggy seat springs of the 19th century, they are still prevalent in mid-priced mattresses. Bonnell springs are a knotted, round-top, hourglass-shaped steel wire coil. When laced together with cross wire helicals, these coils form the simplest innerspring unit, also referred to as a Bonnell unit.
  • Marshall coils, also known as wrapped or encased coils or pocket springs, are thin-gauge, barrel-shaped, knotless coils individually encased in fabric pockets—normally a fabric from man-made, nonwoven fiber. Some manufacturers precompress these coils, which makes the mattress firmer and allows for motion separation between the sides of the bed. As the springs are not wired together, they work more or less independently: the weight on one spring does not affect its neighbours. More than half the consumers who participated in a survey had chosen to buy pocket spring mattresses.[11]
  • Offset coils are an hourglass type coil on which portions of the top and bottom convolutions have been flattened. In assembling the innerspring unit, these flat segments of wire are hinged together with helical wires. The hinging effect of the unit is designed to conform to body shape. LFK coils are an unknotted offset coil with a cylindrical or columnar shape.
  • Continuous coils (the Leggett & Platt brand name is Mira-coil) is an innerspring configuration in which the rows of coils are formed from a single piece of wire. They work in a hinging effect similar to that of offset coils.

The bed coil spring was patented by Louis Andrew Vargha.

Foundation[edit]

There are three main types of foundation.

  • A traditional box spring consists of a rigid frame containing extra heavy duty springs.[12] This foundation is often paired with an innerspring mattress, as it extends the life of the spring unit at the mattress's core. All-foam mattresses are often paired with platform-style bases.
  • An all-wood foundation usually has seven or eight support slats disposed below paperboard or beaverboard. This foundation, variously called a "no-flex," "low-flex" or zero-deflection unit, as well as an "ortho box," provides support similar to a platform foundation. All-wood foundations have become increasingly prevalent as U.S. mattress makers shifted to super-thick, one-sided mattresses.[13]
  • A grid-top foundation is a combination of steel and wood.
  • Typically the measurements of a foundation will be about 1-2" shorter than the measurement of a mattress.

Upholstery layers[edit]

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.[14]

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.

Fabric cover[edit]

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.[15]

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.[16]

Air mattress[edit]

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.[17] 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.

Air mattresses for medical use[edit]

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 the effectiveness of these techniques was still being researched.[18]

Self-inflating air mattresses[edit]

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.

Foam mattress[edit]

All-foam mattresses use different weights and densities of petrochemical-based flexible polyurethane foams when creating the mattress.[19] 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.[20]

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.[21] 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.[citation needed] 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.[22]

Memory foam[edit]

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.[23]

Quality[edit]

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.[24]

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.[citation needed] 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.

Maintenance and care[edit]

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.[citation needed] 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.

See also[edit]

References[edit]

  1. ^ "Mattress". Dictionary.com. Retrieved 2012-05-26. 
  2. ^ "Mattress: Word History." The American Heritage Dictionary.
  3. ^ "Divan". Dictionary.com. Retrieved 2012-05-26. 
  4. ^ Nelles, Barbara. "The Inside Story." BedTimes Magazine. July 2009. Retrieved 2011-9-1
  5. ^ History of California King-sized beds
  6. ^ Aerospace Technology Innovation May/June 1998
  7. ^ "Company History." Simmons website, www.simmons.com. Retrieved 2011-8-21.
  8. ^ based on "Common Mattress Dimensions". Precious Bedding Company. 
  9. ^ Kadvany, Elena (2012-07-05). "S.F. 7-by-7 mattress fits a king-size niche". San Francisco Chronicle. 
  10. ^ Haex, Bart (2005). Back and Bed: Ergonomic Aspects of Sleeping. CRC Press. ISBN 0-415-33297-4. 
  11. ^ Which, published by Consumers Association: Mattresses: Choosing the best type of mattress
  12. ^ "At High Point: Shifman highlights its handcrafting". BedTimes Magazine. Retrieved 2/11/14. 
  13. ^ Nelles, Barbara (Feb 2012). "New features rev up steel frames & support systems". BedTimes Magazine. Retrieved 2/11/14. 
  14. ^ James, Gary. "Gel Foams Meet Fast-Growing Demand." BedTimes Magazine. Oct. 2012. Retrieved 2012-9-26.
  15. ^ Nelles, Barbara. "Dress Up: Mattress Fabrics take on many roles." BedTimes Magazine, November 2009. Retrieved 2011-8-21.
  16. ^ Nelles, Barbara. "Judging a Bed by its Cover." BedTimes Magazine. October 2011. Retrieved 2012-1-2.
  17. ^ Nelles, Barbara. "What's in the air? Category clearly getting off the ground." ''BedTimes Magazine. June 2006.
  18. ^ Alternating pressure air mattresses as prevention for pressure ulcers: A literature review International Journal of Nursing Studies, Volume 45, Issue 5, Pages 784-801 (May 2008)
  19. ^ "Flexible Polyurethane Foams (FPFs) Used in Upholstered Furniture and Bedding." American Chemistry Council: Center for the Polyurethanes Industry. 2008. Retrieved Aug. 15, 2011.
  20. ^ "Product Watch: Green foams grabbing the spotlight." BedTimes Magazine. Feb. 2010. Retrieved Aug. 15, 2011.
  21. ^ "The future of foam: An ever-widening sphere of influence. BedTimes" Magazine. February 2003. Retrieved Aug. 15, 2011.
  22. ^ "Trends in springs and foam: the core components." BedTimes Magazine. August 2011. Retrieved Aug. 15, 2011.
  23. ^ Nelles, Barbara. "Trends in Springs and Foam." BedTimes Magazine, Aug. 2011. Retrieved 2013-8-13
  24. ^ Bain, Duncan. “Pressure Reducing Mattresses.” MHRA. April 2004.