Understanding nylon coatings

**Spaceman** · 08-22-2014, 12:25

I need some help understanding the various coatings used on ripstop nylon. When looking at coated options, I came across the following:
-silicone impregnated
-silicone coated
-PU coated (UV)
-PU coated (FR UV)
-PU coated (clear coat)
-PU coated (opaque coat)
-Heavy Coating (not sure what this meant)

I'm assuming impregnated is better than coated, since coatings can wear off. Any truth to that?

With coated options, is silicone better than polyurethane? Will one or both eventually flake/peel off?

Is it worth paying a slight premium if the same fabric type is offered with different amounts of coating (one with 3/4oz of coating and another with 1oz of coating)?

While a flame retardant (FR) option is not as common, many seem to be available with UV stabilization. When choosing a fabric, are you guys seeking out ones with UV treatment or not worrying about it?

I assumed all coatings were clear, but I found a camo fabric that had a 1oz opaque coating. At the risk of sounding stupid, what is the difference between clear and opaque when it comes to coatings? If the coating was truly opaque, wouldn't it had the fabric pattern?

Finally, are "breathable" ripstops made without any type of coating or do most include some type of DWR?

**ntxkayakr** · 08-22-2014, 13:12

Originally Posted by Spaceman

[COLOR="#FF0000"]are "breathable" ripstops made without any type of coating or do most include some type of DWR?

https://www.hammockforums.net/forum/...ater-repellent

I could be wrong but it was my understanding that double side coated is often just another marketing term for impregnated. Here is an example but call/email this or the vendor you were looking at and ask them:

http://www.rockywoods.com/Fabrics-Ki...p-Nylon-Fabric

rockywoods is one of many vendors that has a wide range of fabrics, I like them because they actually provide a reasonable amount of specifications for their products, except for the "closeouts" or seconds or remnants or mixed lots that are at deep discount, but even those have better specifications than many other vendors provide, some advertise great deals but never ship it to you or are very slow to ship. Your experience may differ, good luck.

Edit: Warbonnetguy says "Actually silnylon is silicone-coated nylon. The term "impregnated" is probably just held over from the way it was first made perhaps. Silnylon is first woven, then dyed, then coated. If you take an abrasive dish pad you can rub the coating right off your silnylon. Alot of places advertise "impregnated", but that's not really an accurate description of how it's actually made. They call it "impregnated" because everyone else does. It's basically a thin silicone coating (usually on both sides)."

After time, stuffing, and destuffing your tarp this silicone coating comes off you ripstop nylon tarp and it begins to mist more and more under heavy rainstorms, but this is not a big deal, just buy another one, still cheaper than Cuben Fiber which does not last forever either, nothing in life does. If you fold your tarp along the same lines repeatedly it could be even worse so, I avoid doing that.

**MAD777** · 08-22-2014, 13:35

Basically all silicone (silnylon) is impregnated.

PU is a coating on one side only. It is generally heavier, harder to fold, and has a history of delamination compared to silnylon.

Both are waterproof.

**ntxkayakr** · 08-22-2014, 13:37

https://www.hammockforums.net/forum/...ed-vs-silnylon

Comment #9 by ChrisH is a must read in my opinion he has excellent experience:

"I spent 27+ years in Textile Research with the CSIRO, ending up as a Senior Principal Research Scientist with a large team under me.
I have a Suter tester (it measures the pressure rating of a fabric) of my own and I have been testing (on my own behalf) light-weight coated fabrics for many years (6+).
I have tested many of the fabrics from the various suppliers in the American cottage industry - (thanks to various people including Sam for all the samples)."

I would not personally consider either PU or Silnylon "waterproof" only water or rain resistant, but read the write up by ChrisH and spend enough time out in the wilderness in heavy down pours and dropping temps and dew points etc before you quickly disagree with me. ChrisH's discussion on "Misting" is one of the best I have read.

**sargevining** · 08-22-2014, 13:42

-PU coated (UV)
-PU coated (FR UV)
-PU coated (clear coat)
-PU coated (opaque coat)

PU = poly urethane

UV = Ultra violet resistant

FR = Fire resistant

Clear coat = you can see through it to the fabric

Opaque coat = you can't

**Ramblinrev** · 08-22-2014, 14:35

Confusion reigns supreme. Nylon is a difficult material to dye. There are generally two ways to make a dyed nylon fabric. One is to dye the fabric after it is woven as Warbonnetguy described. A second approach is to mix the color into the polymer before it is spun into thread. The second is a better product and probably more expensive. To a degree you pays your money and takes your chances. Dyed in the thread gives a more even coloring than dyed in the cloth.

You may still be able to find true impregnated fabric but it would be more expensive and likely a specialized fabric.

Camo patterns are generally printed on rather than dyed. Printed fabric has an easily detected right and wrong side.

**nothermark** · 08-22-2014, 18:23

FWIW If you work with silicone rubbers one of the things you learn is that it chunks under abrasion. I would expect any thin material impregnated with silicone rubber to go porous if scrubbed as the rubber chunks out of the weave. Urethane is a bit more likely to polish but will still flake with enough abrasion.

**Spaceman** · 08-22-2014, 21:05

So if a sil-coated fabric is generally lighter (due to less coating material), stronger (due to the coating being applied to both sides), dries quicker (due to coatings on both sides instead of just the backside) and typically holds it's water-shedding properties longer (due to the shorter shelf life of PU) than a PU-coated fabric of the same denier, why would one chose a PU fabric? Does it come down to cost only? I guess until the PU coating starts to flake off, it probably is more water resistant than sil (higher hydrostatic head), but you get hit with a slight weight penalty and it sounds like it's harder to pack/fold.