Mattress coils, also known as mattress springs, are coil springs used in a mattress. Coils are primarily used in the core (support layer) of innerspring mattresses, which is their original use. In recent years, small "micro-coils" are being used in the upholstery (comfort layer) of mattresses, primarily with a coil core ("coil-on-coil" construction), but sometimes with other core types.
Mattress coils were introduced in the mid-late 19th century, and remain popular in the 21st century, particularly in the United States.
There are four types of mattress coils. A key desiderata is "response range", meaning the change in firmness as the spring is compressed - initially soft, to conform to the body, then hard, to provide support. In increasing order of response range and cost, the types are:
While coil springs were invented in the 15th century, they were not used in mattresses until the mid-late 19th century, following the use of upholstery coil springs in furniture and carriages.
Microcoils were introduced in the early 21st century, and as of 2014are a small part of the market.
The bed coil spring was patented by Louis Andrew Vargha. Some modern feedback on coils within mattresses cast aspersions on some of its attributes such as abrasion on coils eventually culminating into prodding, and the audibility of the coils, as it may decrease privacy for intimate moments such as sexual activity.
The mattress coil market is quite concentrated - the leading suppliers are Leggett & Platt (founded 1883) of Carthage, Missouri and HSM (company) (formally Hickory Springs, founded 1944) of Hickory, North Carolina; others include Spinks Springs (founded 1840) of Leeds, United Kingdom and Subiñas (founded 1959) of Biscay, Spain.. Raha mattresses are the leading mattress manufacturers in Gulf region. Cloudnine mattress is the luxury segment of Poly Products-manufacturer of Raha mattresses.