Pertex

[wisenber]

I believe that the machines/patent has been sold to the Chinese, like a lot of other things, but there are equivalents out there.

According to a BPL article in 2006, Mitsui of Japan bought them out when they went bankrupt. That is the same company that manufactures eVent.

[vitamaltz]

Gailainne, would you recommend a small strip of DWR on an otherwise all-Pertex quilt to help it deflate easier? A few of us have made quilts with sidewalls lately. I'm thinking maybe if everything but the sidewall (same height as the loft) was Pertex, you'd get much of the benefit as well as better packability.

[wisenber]

Gailainne, would you recommend a small strip of DWR on an otherwise all-Pertex quilt to help it deflate easier? A few of us have made quilts with sidewalls lately. I'm thinking maybe if everything but the sidewall (same height as the loft) was Pertex, you'd get much of the benefit as well as better packability.

I'd be curious about which type of Pertex was used. There are about half a dozen types with varying weight/breathability/water resistance. Go Lite and Feathered Friends uses the Endurance and Quantum combined.

[Gailainne]

Gailainne, would you recommend a small strip of DWR on an otherwise all-Pertex quilt to help it deflate easier? A few of us have made quilts with sidewalls lately. I'm thinking maybe if everything but the sidewall (same height as the loft) was Pertex, you'd get much of the benefit as well as better packability.

I may have slighty exagerated how difficult it is to pack, it does feel like it has a mind of its own sometimes though.

The Rab bag I have is Pertex Quantum Endurance according to the blurb, the Alpkit bag has a fabric called Toray, this is what they replaced Pertex with, which is the one thats quite air tight.

I bought 2 types of pertex, Pertex 4 which was the lightest they had in stock, and for the sock and cover I bought some pertex liner, dont have any details on it, apart from it was cheap, and it has the same properties as pertex.

Cheers

Stephen

[NickJ]

the problem with pertex (and in fact any breathable material) is that in fine, wet mist, it just cant breathe. it relies on small particles of water being able to either escape or be "wicked" from one side to the other. if you cover the outside in a fine mist, it just stops working.

if you have a goretex jacket for example, you ll notice that the inside gets damp when youre working hard in very fine rain (and heavy rain too). same principle going on.

i would suggest using silnylon for a sock, but making sure that you had adjustable vent holes at each end to ensure a throughput of air to stop any condensation. plus, its light and packs down to almost nothing.

[wisenber]

the problem with pertex (and in fact any breathable material) is that in fine, wet mist, it just cant breathe. it relies on small particles of water being able to either escape or be "wicked" from one side to the other. if you cover the outside in a fine mist, it just stops working.

if you have a goretex jacket for example, you ll notice that the inside gets damp when youre working hard in very fine rain (and heavy rain too). same principle going on.

i would suggest using silnylon for a sock, but making sure that you had adjustable vent holes at each end to ensure a throughput of air to stop any condensation. plus, its light and packs down to almost nothing.

That is true to an extent with breathable fabrics. However, the wicking/breathing part is also driven by the temperature difference on the inside versus the outside. When the temperature on the inside is warmer, it drives the moisture to the cooler side. This is evident when you sleep with wet socks under your goretex at night. In the morning, the socks will be dry. It is your body heat that drives the vapor through the membrane. Silnylon on the other hand has no such potential to move vapor from a higher temperature gradient to a lower one. The moisture on the inside of the goretex is perspiration not rain. Your perspiration output has exceeded the ability of the membrane to let the moisture vapor escape. Pertex is far less water resistant than goretex, but the volume of moisture it will allow to escape exceeds goretex. That's why pertex is used for a windshirt versus a rain shell.