Multi-layer mattress

1. A mattress, comprising:

a polyurethane layer;

at least one intermediate layer comprising one and only one channel, wherein the channel comprises a ceiling, and the intermediate layer is continuous above the ceiling of the channel, wherein a bottom-most intermediate layer is disposed directly above the polyurethane layer; and

a comfort layer disposed directly above an uppermost intermediate layer wherein (i) the ceiling of the channel in the center of the channel is higher than both the ceiling at an end nearest a head of the mattress and the ceiling at an end nearest a foot of the mattress, and (ii) the channel comprises a floor opposite the ceiling and the floor of the channel in the center of the channel is higher than both the floor at the end nearest the head of the mattress and the floor at the end nearest the foot of the mattress.

2. The mattress of claim 1 , wherein the comfort layer comprises a foam.

3. The mattress of claim 2 , wherein the foam is a viscoelastic foam.

4. The mattress of claim 1 , wherein the one and only channel extends laterally from a first side to an opposite side and has a plurality of support elements disposed in the channel.

5. The mattress of claim 4 , wherein each of the support elements is selected from the group consisting of tubular foam springs, foam spheres, or foam hemispheres.

6. The mattress of claim 1 , wherein at least one intermediate layer comprises a non-viscoelastic foam.

7. A mattress assembly, comprising:

a mattress, comprising:

a polyurethane layer;

at least one intermediate layer comprising one and only one channel, wherein the channel comprises a ceiling, and the intermediate layer is continuous above the ceiling of the channel, wherein a bottom-most intermediate layer is disposed directly above the polyurethane layer;

a comfort layer disposed directly above an uppermost intermediate layer; and

a mattress foundation disposed under the mattress;

wherein (i) the ceiling of the channel in the center of the channel is higher than both the ceiling at an end nearest a head of the mattress and the ceiling at an end nearest a foot of the mattress, and (ii) the channel comprises a floor opposite the ceiling and the floor of the channel in the center of the channel is higher than both the floor at the end nearest the head of the mattress and the floor at the end nearest the foot of the mattress.

8. The mattress assembly of claim 7 , wherein the comfort layer comprises a foam.

9. The mattress assembly of claim 8 , wherein the foam is a viscoelastic foam.

10. The mattress assembly of claim 7 , wherein the one and only channel extends laterally from a first side to an opposite side and has a plurality of support elements disposed in the channel.

11. The mattress assembly of claim 10 , wherein each of the support elements is selected from the group consisting of tubular foam springs, foam spheres, or foam hemispheres.

12. The mattress assembly of claim 7 , wherein at least one intermediate layer comprises a non-viscoelastic foam.

13. A mattress, comprising:

a polyurethane layer;

at least one intermediate layer comprising one and only one channel, wherein the channel comprises a ceiling, and the intermediate layer is continuous above the ceiling of the channel, wherein a bottom-most intermediate layer is disposed directly above the polyurethane layer, and at least one intermediate layer comprises at least one channel extending laterally from a first side to an opposite side and a plurality of support elements disposed in the channel; and

a viscoelastic foam layer disposed directly above an uppermost intermediate layer;

wherein (i) the ceiling of the channel in the center of the channel is higher than both the ceiling at an end nearest a head of the mattress and the ceiling at an end nearest a foot of the mattress, and (ii) the channel comprises a floor opposite the ceiling and the floor of the channel in the center of the channel is higher than both the floor at the end nearest the head of the mattress and the floor at the end nearest the foot of the mattress.

14. The mattress of claim 13 , wherein each of the support elements is selected from the group consisting of tubular foam springs, foam spheres, or foam hemispheres.