The cover of a mattress is called ticking ( from the Latin word for sheath: "theca" via the old English word "tykke".)
Lower quality sofa bed mattresses have zippers, or some way to get at the foam core. Why? Because the cover shifts around. Cheap mattresses need a way for you to remove and reposition the cover. Think about the stresses on the cover every time the sofabed is folded up. The ticking will begin to slide around the core on the very first time you "close" the sofa..
Once the quilted seams start shifting around, you will be sleeping, (or at least trying to sleep) on them. With a zipper on the ticking, you can fix this. But come on, can you really see taking the cover off the foam and trying to get it back on in the right place? Can you see doing it every other week?
We mechanically attach the cover to the foam. ( See "About The Construction
" ) button on the right.
The cover is made to be durable. 100% cotton 225 thread count cotton canvas fabric, with diamond quilted construction. The seam tape is of a similar material. In mattress jargon the cover is a quilted cotton damask. It is the best material for use for a sofabed mattress cover. We also take care to use strong mildew resistant thread to sew the ticking together. Our mattress don"t "come apart at the seams."

The final assembly of the mattress involves involves sewing the "skirt" , ( See " About The Construction " ), to the side, top and bottom. Together they form the "ticking." This is done using a remarkable sewing machine; (also in " About The Construction " )
We take particular pride it the construction of the seams. Our machine uses 2 needles to lay down two interconnected types of stitch.
This stitch is technically a "double-needle-lock-chain-stitch"

It is resistant to unraveling and extremely strong. The needles in this machine are designed to be least likely to do damage while piercing the fabric.
This diagram shows the stitches the two needles do. It shows them separately, but they interlock in practice.
The threads driven by the needles are shown in red, The green and blue threads are interlocked by the bobbin.
There is a video embedded in the image (just hold the mouse over it).
It only shows part of the process, but the animation was just too cool to leave it out.
Finally, our mattress meets Federal Flammability Standards. This is really important stuff as the following picture shows. On the left is a mattress which has an ordinary cover The mattress on the right has a federal flammability standards compliant cover. The same ignition source was used for both mattresses. Both images were taken 3 minutes after first ignition.
This picture is taken from a video on the U.S. Consumer Product Safety Commission (CPSC) website. If you want to see this really scary video,
check it out here
.
My name is David Paul. I am the proprietor, and stand behind these statements and every other statement made on this web site. Call me anytime. - - Cell: (732) 921 0106 - -