FIELD OF INVENTION
The present invention relates to a mattress, specifically relates to a mattress with a unique layered structure.
BACKGROUND OF THE INVENTION
Traditionally, the mattress industry in India consisted of Coir and Cotton mattress categories. Foam and spring mattresses have recently been introduced as new categories in India. Specialty mattresses being sold include latex mattresses and viscoelastic (memory) foam mattresses.
Coir and Cotton mattresses generally are very firm and not so durable. They do not conform to human body and provide poor support resulting in excessive pressure on critical bony joints such as hip and shoulder joints, which results in frequent tossing and turning during the night. The entire weight of the sleeper is exerted on few areas of the mattress rather than being distributed along the entire length. These results in sagging of the mattress along areas under excessive pressure (also referred to as “bottoming out”). These mattresses bottom out in short duration of use and exhibit a “hard feel” (i.e. no rebound or resiliency) upon sleeping on it. Sleeping on a bottomed out mattress further worsens functioning of critical bony joints, negatively impacts quality of sleep and impairs overall health and wellness.
Conventional Polyurethane (PU) foam mattresses have gained significant market share of organized mattress industry in India. U.S. Patent No. 5,031,261 granted to William G. Fenner Sr. on 16th of July 1991, a laminated polyurethane foam mattress invention is disclosed which is formed of two layers. A horizontal layer of polyurethane foam with lower Indentation Load Deflection (ILD) is positioned above a base layer of polyurethane foam of higher ILD. Such conventional PU foam mattresses have inferior mechanical properties and are also not so durable. Like coir and cotton mattresses, conventional PU foam mattresses also bottom out and results in similar aforementioned issues. When compared with latex mattressesthey have poor support and lower resiliency or rebound (“bounce”). When compared with memory foam mattresses they provide no pressure relief, poor weight distribution and no motion transfer isolation.
Low resiliency viscoelastic (“memory”) foam is specialized polyurethane foam characterized by its slow recovery on deformation, which aids in pressure relief. Memory foam was invented as a result of NASA’s research on energy absorbing foam to prevent damage to astronauts during space missions in the mid 1960s. It was introduced to the US mattress industry in the early 1990s as pressure relieving foam with motion transfer isolation properties (i.e. if one sleeper moves it does not disturb another adjacent sleeper).In U.S. patent number 6,541,094 granted to Dan Landvik and Michael Allaway, a laminated viscoelastic foam mattress construction is described for pressure-relief. An upper layer of softer viscoelastic foam followed by a layer of viscoelastic foam of greater hardness (or firmness) is placed over bottom layer of highly resilient polyurethane foam. However, memory foam mattresses such as the one described in aforementioned
patent,have significant disadvantages such as: 1) “Being stuck”, “sinking in” and “quicksand” feeling: Sleepers sink in the foam as body heat energy is transferred to the foam (i.e. sleeper often find it difficult to turn over when changing sleeping position). This is also uncomfortable for couples during sexual intercourse. 2) Sleeping “hot”: Memory foamswith closed cellstructure have poor airflow. The heat does not dissipate resulting in heat retention on the sleeping surface, which leads to poor quality of sleep with frequent tossing and turning.
Latex has very high resiliency (i.e. “bounce”), breathability (i.e. air flow) and provides good support. The consumer complaints reported against latex mattresseslist its excessive bounce and pressure on bony joints and poor comfort as major reasons.Springiness of latex also causes excessive motion transfer (i.e. movements of one sleeper disturbs adjacent sleeper). Additionally, 1% of world population is known to be allergic to natural or blended latex.
SUMMARY OF INVENTION
The present invention has been developed in response to the present state of the art, and in particular, in response to the problems and needs in the art that have not yet been fully solved by currently available techniques and processes. Accordingly, the present invention has been developed to provide benefits of high resiliency foams (latex, latex-like foam or High Resiliency polyurethane foam) and low resiliency (viscoelastic) foam, without foregoing drawbacks.
The current invention, In one embodiment, comprises of a horizontal layer of viscoelastic foam is positioned on top to provide comfort, allow motion transfer isolation as it contours around the body and better weight distribution. The second horizontal layer of high resiliency foam is sandwiched and positioned below the first horizontal layer to prevent sleeper from sinking deeper, improve airflow and provide support to the sleeper’s body. The third horizontal layer of viscoelastic foam is positioned below the second horizontal layer and provides deep pressure relief to critical bony joints such as hip and shoulder joints. These 3 layers forming a sandwich structure may be positioned above support core. This construction provides pressure relief, bounce, motion transfer isolation and support, while also alleviating feeling of “getting stuck”, “sleeping hot” and “excessive pressure and bounce”.
Therefore, the main objective of the present invention to provide a novel foam mattress construction that provides benefits of high resiliency foams (latex, latex-like foam or High Resiliency polyurethane foam) and low resiliency (viscoelastic) foam.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying figures, where like reference numerals refer to identical or functionally similar elements throughout the separate views, together with the detailed description below, are incorporated in and form part of the specification, and serve to further illustrate embodiments that include the claimed invention, and explain various principles and advantages of those embodiments. The description is meant to be taken in conjunction with the accompanying drawings in which: FIG. 1is a cross-sectional view of a in accordance with some embodiments. FIG. 2A is a cross section view of a mattress in accordance with some embodiments. FIG. 2B is a perspective view of a mattress in accordance with some embodiments. Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of various embodiments. In addition, the description and drawings do not necessarily require the order illustrated. Device and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the various embodiments so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein. Thus, it will be appreciated that for simplicity and clarity of illustration, common and well-understood elements that are useful or necessary in a commercially feasible embodiment
may not be depicted in order to facilitate a less obstructed view of these various embodiments.
DETAILED DESCRIPTION OF INVENTION
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Illustrative embodiments of the invention now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the invention are shown. Indeed, the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout. Before proceeding with the detailed description key terms and their definition pertinent to this disclosure are explained below. I. Key terms and their definition a) Density- Density of foam is its mass per unit volume. Density may be measured in pounds per cubic foot (pcf) or kg per cubic meters (kg/m3 or D). Dentisty of the foam determines the grade of the foam. Higher density implies better grade, and therefore better durability.
b) Indentation Force Deflection (IFD): Indentation Force Deflection (IFD) tests measure firmness of flexible foams. IFD is defined as the amount of force, in pounds, required to indent a fifty square inch round indentor foot into a predefined foam specimen a certain percentage of the specimen's total thickness. IFD is usually measured at 25% and 65% deflection (i.e. compression) of the specimen's height and is measured in pounds. IFD at 25% means the amount of load (in pounds) required to indent or compress 4-inch thick sample of foam until it reaches 3-inches of thickness. For example, IFD at 25% value of 10 means 10 lbs of load is required to indent or compress 4-inch foam by 1 inch or in other words, until it reaches a thickness of 3-inches.Higher IFD implies more firmness. Lower IFD indicates softer foam. The term IFD is interchangeable with Indentation Load Deflection (ILD). c) Support Factor (SF): SF of foam is the ratio of 65% IFD over 25% IFD and is a unitless measurement. Higher SF implies better support of foam. Foams with lower SF values bottoms out easily. d) Resiliency or Rebound: Resiliency or rebound of foam is its ability to spring back to original shape or position. e) Recovery: Recovery of foam is a measure of how quickly a foam returns to original shape after being displaced and is measured in seconds. It is usually used for measuring recovery time of viscoelastic foams. f) Airflow: Airflow of foam is a measure of its air permeability. It is measured in standard cubic feet per minute (scfm). Higher airflow values make foam more breathable which aides in heat dissipation.
g) Glass Transition Temperature (Tg): The glass transition temperature of foam is defined as the temperature range where the foam changes over from a firm state to a soft and flexible state. This is mostly applicable to viscoelastic foam where its mechanical properties are attributed to its glass transition temperature. At temperature above Tg, memory foam feels softer and loses its viscoelastic properties. At temperatures below Tg, it feels firmer and becomes too viscoelastic (no or extremely slow recovery). h) Viscoelastic Foam: Viscoelastic foamsare temperature sensitive polyurethane foams with a low resilience and slow recovery from deformation. Viscoelastic foam, herein, refers to any foam where: i. Tg between 0 °C and 40 °C; ii. Resiliency is less than 25%; iii. Recovery timeis greater than 1 second. i) Latex Foam: Latex foam is a foam, that is produced from liquid latex by process of vulcanization. It may be natural (plant based), synthetic (chemical based) or blended. Synthetic latex most commonly is made from Styrene Butadiene Rubber (SBR) but may also be made from other chemicals. Blended latex may be any blend of natural latex, synthetic latex, polyurethane or polyethylene materials. Latex foam, herein, refers to foam where: i. Resiliency may be greater than 40%; ii. Support Factor (SF) may be greater than 2; iii. Airflow may be greater than 0.94 L/s.
j) Latex-like Foam: Latex-like foam, herein, is referred to any non-latex foam that simulatesaforementioned mechanical properties (resiliency, support factor, and airflow) of latex foam. They are most often polyurethane based but can be made from other chemicals. k) High Resiliency (HR) Polyurethane Foam: HR foam is afoam that has higher resiliency than conventional foam. HR foam, herein, refers to a foam where: i. Resiliency may be greater than 40%; ii. Support factor (SF) may be greater than 2; l) Support Core: Support core, herein, is defined as any foam or combination of foam, springs, pocket coils and any natural or artificial fibers, placed to provide basal support and may be made of one or more layers. II. Test Methods A. American Society of Testing and Materials (ASTM) has formulated standardized tests that are globally used for testing aforementioned properties: i. ASTM D3574-11 Test B1: An 8 inch diameter steel plate (called as indentor foot) is used to indent or compress into a foam sample to a stated percentage of the test sample’s initial height. The amount of load (in pounds) needed to compress the foam sample to 25% and 65% of its total thickness is measured. The measurements at 25% and 65% are referred to as IFD at 25% and IFD at 65% respectively. IFD at 25% is usually used as industry standard to indicate hardness of a foam. IFD at 65% is used to calculate Support Factor (SF) or compression modulus of a foam, where:
SF = (𝐼𝐹𝐷𝑎𝑡 65%)/(𝐼𝐹𝐷𝑎𝑡 25%) ii. ASTM D3574-11 Test H: A steel ball of 16 mm diameter, weighing 16.3 gm, is dropped through a vertical clear plastic tube onto a foam sample and the height of rebound is expressed as the percentage of the original ball drop height. iii. ASTM D3574-11 Test M:The indentor foot (as described in Test B1) is used to indent or compress a foam specimen with 4.5N of force and time taken to recover from compression is recorded in seconds. iv. ASTM D3574-11 Test G: Air is passed through 1 inch thick foam sample of 2 inch length and 2 inch breadth at 125 Pa of pressure and the volume of air that escapes on the other end is measured. Airflow values are expressed in Litre per second (L/s) or standard cubic feet per minute (scfm). B. Dynamic Mechanical Thermal Analysis (DMTA): In this analysis, sinusoidal (i.e. smooth repetitive oscillation,) deformation is applied to a foam sample. The response of foam under varying degrees of stress, strain and temperatures is studied. Stiffness and dampness of the foam sample are recorded.Stiffness refers to the elastic behavior and dampness refers to how well foam performs at absorbing energy. Dampness is recorded as tan delta curve, which is a ratio of viscous to elastic response of viscoelastic foam.Glass transition temperature (Tg) is the temperature point corresponding to the peak value of this tan delta curve. The testing methods are done in controlled settings and are intended to provide global standardization. However, performance of foams with similar values may vary in
different geographic weather and housing conditions of variable temperature, humidity, atmospheric pressure, wind, or precipitation. III. Dimensions The invention described, herein, may be of any length and width. It relates to all Indian or global sizes, standard or non standard. The total thickness of the mattress may range from 1 to 22 inches. IV. Embodiments
In the embodiments described below, low and high resiliency foams are utilized in a novel way to provide their unique benefits while also minimizing their drawbacks. A horizontal layer of viscoelastic foam is positioned on top to provide comfort, allow motion transfer isolation as it contours around the body and better weight distribution. The second horizontal layer of high resiliency foam ispositioned below the first horizontal layer to prevent sleeper from sinking deeperby providing bounce and therefore minimizing “being stuck” and “quicksand” feeling of low resiliency viscoelastic foam, improve airflow andprovide support to the sleeper’s body. Better airflow of high resiliency foam aids in heat dissipation and therefore prevents excessive heat retention in the top low resiliency viscoelastic foam layer.The third horizontal layer of low resiliency viscoelastic foam is positioned below the second horizontal layer to provide deep pressure relief to critical bony joints such as hip and shoulder joints. These 3 layers forming a sandwich apparatus may be positioned above support core. This construction provides pressure relief, bounce, motion transfer isolation and support, while also
alleviating feeling of “getting stuck”, “sleeping hot” and “excessive pressure and bounce”.
A. First Embodiment: In afirst embodiment as depicted in FIG. 1, mattress 100 having total thickness 195 of 1 to 22 inches, preferably 3 to 13 inches.A horizontal layer of viscoelastic foam 120 is positioned on top to provide comfort, allow motion transfer isolation as it contours around the body and better weight distribution. This layer has thickness 160 of 0.25 to 5 inches, preferably 0.5 to 2 inches, more preferably 0.5 to 1.5 inches and most preferably 0.5 to 1.0 inch. The mechanical properties are listed:
i. Density of 32 to 130 kg/m3, preferably 40 to 90 kg/m3, more preferably 48 to 80 kg/m3 and most preferably 60 to 70 kg/m3.
ii. IFD at 25% of 3 to 24, preferably 6-18, more preferably 8-16 and most preferably 10-14.
iii. Support Factor of 1.1 to 3.2, preferably 1.6 to 2.7, more preferably 1.8 to 2.5 and most preferably at 1.9 to 2.3.
iv. Resiliency of less than 25%, preferably less than 10%, more preferably less than 5% and most preferably less than 2%.
v. Recovery of greaterthan 1 second, preferably 2 to 15seconds, more preferably 3 to 10seconds and most preferably 3 to 7 seconds.
vi. Airflow of greater than 0.2L/s, preferably greater than 0.47 L/s, more preferably greater than 0.7 L/s and most preferably greater than 0.9 L/s.
vii. Glass Transition Temperature Tg (DMTA) is between 0°C and 40 °C, preferably between 10 °C to 30 °C, more preferably between 12 °C to 24 °C and most preferably 15 °C to 21 °C.
A second horizontal layer of high resiliency foam 130 is sandwiched and positioned below the first horizontal layer to prevent sleeper from sinking deeper, improve airflow and provide support to the sleeper’s body. This may be Latex, Latex-like foam or High Resiliency (HR) polyurethane foam layer with thickness 170 of 0.25 to 5 inches, preferably 0.5 to 2 inches and more preferably 0.5 to 1.5 inches. The mechanical properties are listed:
i. Density of 30 to 150 kg/m3, preferably 35 to 100 kg/m3, more preferably 48 to 80 kg/m3 and most preferably 55 to 70 kg/m3.
ii. IFD at 25% (ASTM D3574-11 Test B1) of 5 to 35, preferably 10-26, more preferably 12-22 and most preferably 14-18.
iii. Support Factor (ASTM D3574-11 Test B1) of greater than 2, preferably greater than 2.5, more preferably greater than 3 and most preferably greater than 3.5.
iv. Resiliency (ASTM D3574-11 Test H) of greater than 40%, preferably more than 50%, more preferably greater than 60% and most preferably 60% to 70%.
v. Airflow (ASTM D3574-11 Test G) of greater than 0.94L/s, preferably greater than 1.4 L/s and more preferably greater than 1.65 L/s.
A third horizontal layer of viscoelastic foam 140 provides deep pressure relief to critical bony joints such as hip and shoulder joints. This layer has thickness 180 of 0.25 to 5 inches, preferably 0.5 to 3 inches, more preferably 0.5 to 2 inches and most preferably 1 to 2 inches. The mechanical properties are listed:
i. Density of 32 to 130 kg/m3, preferably 40 to 90 kg/m3, more preferably 48 to 80 kg/m3 and most preferably 60 to 70 kg/m3.
ii. IFD at 25% of 3 to 24, preferably 6 to 21, more preferably 8 to 18 and most preferably 10-16.
iii. Support Factor of 1.1 to 3.2, preferably 1.6 to 2.7, more preferably 1.8 to 2.5 and most preferably at 1.9 to 2.3.
iv. Resiliency of less than 25%, preferably less than 10%, more preferably less than 5% and most preferably less than 2%.
v. Recovery of greater than 1 second, preferably 2 to 15 seconds, more preferably 3 to 10 seconds and most preferably 3 to 7 seconds.
vi. Airflow of greater than 0.2 L/s, preferably greater than 0.47 L/s, more preferably greater than 0.7 L/s and most preferably greater than 0.9 L/s.
vii. Glass Transition Temperature Tg (DMTA) is between 0°C and 40 °C, preferably between 10 °C to 30 °C, more preferably between 12 °C to 24 °C and most preferably 15 °C to 21 °C.
These three layers120, 130 and 140 forms a sandwich apparatus, which may be positioned above support core 150. Support core provides basal support to the mattress.It
may be made of one or more layers of latex, latex-like foam, viscoelastic foam, inner springs, pocket coils, natural, artificial fibers or any combination thereof. It may have total thickness190 of 0.5 to 15 inches thick, preferably 2 to 12 inches. The mattress may also comprise a cover 110.
B. Second embodiment: In a second embodiment as depicted in FIG. 2A and FIG. 2B, mattress 200 may have a total thickness 290 similar to first embodiment and have a top layer of viscoelastic foam 210 quilted with mattress ticking (i.e. cover) fabric. This quilted layer may have thickness 250 of0.25 inch to 3 inches, preferably 0.5 to 2 inches, more preferably 0.5 to 1.5 inches and most preferably 0.5 to 1 inch.Viscoelastic foam used, herein, may be following mechanical properties:
i. Density of 16 to 90 kg/m3, preferably 25 to 80 kg/m3, more preferably 32 to 72 kg/m3 and most preferably 48 to 64 kg/m3.
ii. IFD at 25% of 3 to 18, preferably 5-16, more preferably 6-14 and most preferably 8-12.
iii. Support Factor of 1.1 to 3.2, preferably 1.6 to 2.7, more preferably 1.8 to 2.5 and most preferably at 1.9 to 2.3.
iv. Resiliency of less than 25%, preferably less than 10%, more preferably less than 5% and most preferably less than 2%.
v. Recovery of greater than 1 second, preferably 2 to 15 seconds, more preferably 3 to 10 seconds and most preferably 3 to 7 seconds.
vi. Airflow of greater than 0.3 L/s, preferably greater than 0.47 L/s, more preferably greater than 0.7 L/s and most preferably greater than 0.9 L/s.
vii. Glass Transition Temperature Tg (DMTA) is between 0°C and 40 °C, preferably between 10 °C to 30 °C, more preferably between 12 °C to 24 °C and most preferably 15 °C to 21 °C.
The second horizontal layer 220 is similar in properties and thickness 260to second horizontal layer of first embodiment. The third horizontal layer 230 is similar in properties and thickness270 to second horizontal layer of first embodiment. These three layers 210, 220 and 230form a sandwich apparatus, which may be positioned above support core240. The support core 240 is similar in properties and thickness 280 to support core of first embodiment.
In the foregoing disclosure, specific embodiments have been described. However, one of ordinary skill in the art appreciates that various modifications and changes can be made without departing from the scope of the invention as set forth in the claims below. Accordingly, the specification and figures are to be regarded in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within the scope of present teachings.
Skilled artisan will also appreciate the range of values for mechanical properties provided in the foregoing disclosure is intended to allow invention to perform in different geographical weather and housing conditions with variability of temperature, humidity, atmospheric pressure, wind or precipitation. The benefits, advantages, solutions to problems, and any element(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential features or elements of any or all the claims.
The invention is defined solely by the appended claims including any amendments made during the pendency of this application and all equivalents of those claims as issued. Moreover in this document, relational terms such as first, second and third; top and bottom; and the like may be used solely to distinguish one entity from another entity without necessarily requiring or implying any such actual relationship or order between such entities. The terms “comprises,” “comprising,” “has”, “having,” “includes”, “including,” “contains”, “containing” or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises, has, includes, contains a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by “comprises . . . a”, “has . . . a”, “includes . . . a”, “contains . . . a” does not, without more constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises, has, includes, contains the element. The term “sandwich” or “sandwiched” are intended to be only illustrative and not to be used in restrictive sense unless explicitly stated otherwise herein. The terms “a” and “an” are defined as one or more unless explicitly stated otherwise herein. The terms “substantially”, “essentially”, “approximately”, “about” or any other version thereof, are defined as being close to as understood by one of ordinary skill in the art. The term “positioned” as used herein is defined as attached, although not necessarily directly and not necessarily mechanically. A structure or apparatus that is “constructed” in a certain way is constructed in at least that way, but may also be constructed in ways that are not listed.This is done merely for the sake of convenience and to provide a general sense of the scope of the invention.
The Abstract of the disclosure is provided to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description of Invention, it can be seen that various features are grouped together in various embodiments for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Thus the following claims are hereby incorporated into the Detailed Description of Invention, with each claim standing on its own as a separately claimed subject. Those skilled in the art will also appreciate that the above recognized advantages and other advantages described herein are merely exemplary and are not meant to be a complete rendering of all of the advantages of the various embodiments of the present invention.

We claim: 1. A mattress comprising: a sandwich apparatus of top horizontal layer of low resiliency viscoelastic foam; a second or sandwiched horizontal layer of high resiliency foam; a third horizontal layer of low resiliency viscoelastic foam; and a support core of one or more layers of any foam or combination of foam, springs, pocket coils and any natural or artificial fibers. 2. The mattress as claimed in Claim 1, wherein the top horizontal layer of low resiliency viscoelastic foam has: A resiliency of approximately less than 25%; A recovery time of approximately more than 1 seconds; and a glass transition temperature (Tg) of approximately between 0oC to 40 oC. 3. The mattress as claimed in Claim 2, wherein the top horizontal layer of low resiliency viscoelastic foam has: a density of approximately 32 to 130 kg/m3; an IFD at 25% of approximately between 3 to 24; an airflow approximately greater than 0.2 L/s; and a support factor (SF) of approximately between 1.1 to 3.2.
4. The mattress as claimed in Claim 1, wherein the second horizontal layer of high resiliency foam has: aresiliency of approximately more than 40%; and asupport factor (SF) is approximately greater than 2; 5. The mattress as claimed in Claim 4, wherein the second horizontal layer of high resiliency foam has: a density of approximately between 30 to 150 kg/m3; an IFD at 25% of approximately between 6 to 35; and an airflow approximately greater than 0.94 L/s. 6. The mattress as claimed in Claim 1, wherein the third horizontal layer of low resiliency viscoelastic foam has: a resiliency of approximately less than 25%; a recovery time of approximately more than 1 seconds; and a glass transition temperature (Tg) of approximately between 0oC to 40 oC. 7. The mattress as claimed in Claim 6, wherein the third horizontal layer of low resiliency viscoelastic foam has: a density of approximately 32 to 130 kg/m3; an IFD at 25% of approximately between 3 to 24; an airflow approximately greater than 0.2 L/s; and a support factor (SF) of approximately between 1.1 to 3.2.
8. The mattress as claimed in Claim 1, wherein the first horizontal layer of low resiliency viscoelastic foam is quilted with mattress cover fabric. 9. The mattress as claimed in Claim 8, wherein the first horizontal layer of low resiliency viscoelastic foam has a density of approximately 16 to 90 kg/m3; wherein the first horizontal layer of low resiliency viscoelastic foam has an IFD at 25% of approximately between 3 to 18; wherein the first horizontal layer of low resiliency viscoelastic foam has a support factor (SF) of approximately between 1.1 to 3.2. wherein the first horizontal layer of low resiliency viscoelastic foam has a resiliency of approximately less than 25% wherein the first horizontal layer of low resiliency viscoelastic foam has a recovery time of approximately greater than 1 seconds wherein the first horizontal layer of low resiliency viscoelastic foam has an airflow approximately greater than 0.2 L/s; and wherein the first horizontal layer of low resiliency viscoelastic foam has a glass transition temperature of approximately between 0 oC to 40 oC.