Hello Jari
I've found this re tube fabrics whilst 'surfing'
Types of Fabric
A major component of an inflatable is obviously the fabric. Fabric technology has evolved greatly over the last 20 to 30 years, and now includes plastomers, polyurethanes and other fabrics, which can sometimes be stronger, lighter, thinner and less expensive to assemble than the original rubber fabrics. Of course it costs a great deal of money to develop new fabrics or even to switch manufacturing processes to use them. Many manufacturers, big and small, don't have the will or the resources to do this, and that's why they generally hide that fact by resorting to condemning new technological advances in fabrics.
For instance, Zodiac's fabrics have always been on the leading edge of technology and their willingness to research and experiment has led to some innovative new fabrics. These new fabrics are developed to be the best for their intended use. Fabrics used for a small tender don't need to be the same as those for a large RIB, because the intended use is not the same. Some manufacturers do not have the means or know-how to employ different fabrics, so they just use one. In these cases the consumer, may end up paying too much or getting too little.
Most fabrics consist of a strong, close-weave mesh of polyester or nylon material which is sandwiched between 2 coatings to provide extreme flexibility, superior air and water tightness, as well as resistance to abrasion and the sun's UV rays. Zodiac uses a polyurethane fabric called "Strongan" and assembles their inflatable boats by thermobonding the fabric.
Heavy Duty Fabrics
Some inflatable boats are still made from a rubber-based fabric called Hypalon. While this is still a very good material, its major downfall is that it can only be joined by gluing, done manually. Problems including poor bonds, delamination of seams or fabric can still affect these glued fabrics. Today, many inflatables are manufactured from polyurethane fabrics, although larger inflatables (particularly RIBs used for rescue or military purposes) use hypalon because thicker hypalon fabrics are still considered to be stronger and more durable than polyurethane. There are some hypalon fabrics that are "2-ply" or a double unit made up of hypalon/weave/hypalon/weave/hypalon and are used for extreme situations including bumper padding, bow skirts, anti-chafe patches and similar applications.
Seams
Apart from its superior toughness and durability, Zodiac's Strongan fabric allows the use of Zodiac's computerized machine-welding process known as "thermobonding", the welding of fabric using hot air. Two sealing strips are thermally bonded to the butted fabric seams in a continuous electrothermal process. A highly airtight seal is created when the narrow inner strip literally melts into the collar material. The wider exterior strip functions as a overlapping structural connection and a sealer against water penetration. Thermobonding creates seams that are typically stronger than the fabric itself and produces a better seam than any hand-gluing method.
Keith Hart
