Waterproof breathable material just around the corner?

http://news.bbc.co.uk/1/hi/technology/7587702.stm

The chemical coating covers just the fibres, rather than forming a
"skin" across the whole surface, as with currently available
waterproofing treatments. That means the spaces between fibres remain
open and the fabric is still breathable.

Tosspot wrote:
http://news.bbc.co.uk/1/hi/technology/7587702.stm

The chemical coating covers just the fibres, rather than forming a
"skin" across the whole surface, as with currently available
waterproofing treatments. That means the spaces between fibres remain
open and the fabric is still breathable.

This will be good for cotton fabric, but not for the polyester and similar
materials that much cycling gear is made of, because the fibres are already
waterproof.

~PB

On Sun, 31 Aug 2008 09:31:43 +0200, Tosspot
wrote:

http://news.bbc.co.uk/1/hi/technology/7587702.stm

The chemical coating covers just the fibres, rather than forming a
"skin" across the whole surface, as with currently available
waterproofing treatments. That means the spaces between fibres remain
open and the fabric is still breathable.

From the article : "The shoes were also subjected to flexing and wear
tests, maintaining their breathable waterproof properties even after
100,000 flexes."

Is 100,000 flexes a realistic test? For example my 1200 miles this
summer on my recumbent (meagre by the standards of many regulars in
this NG) at just under 13mph at a cadence of 70 or more equals
(1200/13) *60 *70 or about 387,700 flexes per shoe.

For a runner, where the shoes flex more, 100,000 flexes doesn't sound
like a lot either, but I've no accurate idea how far a runner goes for
one pace.

Peter Grange wrote:

From the article : "The shoes were also subjected to flexing and wear
tests, maintaining their breathable waterproof properties even after
100,000 flexes."

Is 100,000 flexes a realistic test? For example my 1200 miles this
summer on my recumbent (meagre by the standards of many regulars in
this NG) at just under 13mph at a cadence of 70 or more equals
(1200/13) *60 *70 or about 387,700 flexes per shoe.

For a runner, where the shoes flex more, 100,000 flexes doesn't sound
like a lot either, but I've no accurate idea how far a runner goes for
one pace.

One metre would be a useful approximation, though most runners will have
a single stride a bit longer than that. So, for a 10km run that amounts
to 5000 flexes per shoes. For a marathon it would amount to 21000 flexes
per shoe. Their tests would be good for 200k. The support/cushioning of
a shoe that is hammered on pavements and roads would probably last 500
to 1000km.

Colin

Tosspot wrote:
Pete Biggs wrote:
Tosspot wrote:
http://news.bbc.co.uk/1/hi/technology/7587702.stm

The chemical coating covers just the fibres, rather than forming a
"skin" across the whole surface, as with currently available
waterproofing treatments. That means the spaces between fibres
remain open and the fabric is still breathable.

This will be good for cotton fabric, but not for the polyester and
similar materials that much cycling gear is made of, because the
fibres are already waterproof.

The fibres may be, but the garments aren't. Try wearing my fleece in
the last downpour I was caught in. I swear it held 2 litres of fresh
rainfall.

Exactly. The new product won't help your fleece because the spaces between
the fibres will remain open. You've got to either fill the spaces up or use
a material with no spaces.

~PB

Pete Biggs wrote:
Tosspot wrote:
http://news.bbc.co.uk/1/hi/technology/7587702.stm

The chemical coating covers just the fibres, rather than forming a
"skin" across the whole surface, as with currently available
waterproofing treatments. That means the spaces between fibres remain
open and the fabric is still breathable.

This will be good for cotton fabric, but not for the polyester and similar
materials that much cycling gear is made of, because the fibres are already
waterproof.

The fibres may be, but the garments aren't. Try wearing my fleece in
the last downpour I was caught in. I swear it held 2 litres of fresh
rainfall.

Tim Woodall wrote:
On Sun, 31 Aug 2008 16:49:31 +0200,
Pete Biggs
wrote:
Tosspot wrote:
Pete Biggs wrote:
Tosspot wrote:
http://news.bbc.co.uk/1/hi/technology/7587702.stm

The chemical coating covers just the fibres, rather than forming a
"skin" across the whole surface, as with currently available
waterproofing treatments. That means the spaces between fibres
remain open and the fabric is still breathable.

This will be good for cotton fabric, but not for the polyester and
similar materials that much cycling gear is made of, because the
fibres are already waterproof.

The fibres may be, but the garments aren't. Try wearing my fleece
in the last downpour I was caught in. I swear it held 2 litres of
fresh rainfall.

Exactly. The new product won't help your fleece because the spaces
between the fibres will remain open. You've got to either fill the
spaces up or use a material with no spaces.

That's not what I understand. I think these fibres are water repellant
rather than just waterproof.

Polyester (and similar) fibres already cannot absorb water, so there's
nothing to repel from within the fibres. How is any product going to repel
water from between the fibres without filling the spaces?

So it won't stop you getting wet, but once you take the garment out of
the rain all the water will immediately run out and will, effectively,
be instantly dry to put on again.

I talked about this in another thread w.r.t. shoes. The big problem I
find with shoes, isn't getting wet feet, but is getting the shoes dry
again.

Some shoes are made of fibres that do absorb water, and there can be
relatively large spaces in between the fibres for water to escape relatively
quickly, so the product could be useful for them.

But how is it going to help with a polyester fleece or jersey? These
garments already dry quickly because the fibres are waterproof. It's just
the water trapped in between the fibres that keeps them wet for a while.
Does the product force this trapped water out? How?

~PB

On Sun, 31 Aug 2008 16:49:31 +0200,
Pete Biggs wrote:
Tosspot wrote:
Pete Biggs wrote:
Tosspot wrote:
http://news.bbc.co.uk/1/hi/technology/7587702.stm

The chemical coating covers just the fibres, rather than forming a
"skin" across the whole surface, as with currently available
waterproofing treatments. That means the spaces between fibres
remain open and the fabric is still breathable.

This will be good for cotton fabric, but not for the polyester and
similar materials that much cycling gear is made of, because the
fibres are already waterproof.

The fibres may be, but the garments aren't. Try wearing my fleece in
the last downpour I was caught in. I swear it held 2 litres of fresh
rainfall.

Exactly. The new product won't help your fleece because the spaces between
the fibres will remain open. You've got to either fill the spaces up or use
a material with no spaces.

That's not what I understand. I think these fibres are water repellant
rather than just waterproof.

So it won't stop you getting wet, but once you take the garment out of
the rain all the water will immediately run out and will, effectively,
be instantly dry to put on again.

I talked about this in another thread w.r.t. shoes. The big problem I
find with shoes, isn't getting wet feet, but is getting the shoes dry
again.

Tim.


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and there was light.

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On Sun, 31 Aug, Pete Biggs wrote:

Polyester (and similar) fibres already cannot absorb water, so
there's nothing to repel from within the fibres. How is any
product going to repel water from between the fibres without
filling the spaces?

By making the fibre surface positively hydrophobic. Water will then
only penetrate if under pressure - otherwise droplets will tend to
form and run off.

regards, Ian SMith
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|o o|
|/ \|

Tim Woodall wrote:

Polyester (and similar) fibres already cannot absorb water, so
there's nothing to repel from within the fibres. How is any product
going to repel water from between the fibres without filling the
spaces?

Because the fibres are non-wetting in water. If the water sticks to
itself better than it does to the treated fibres then it will all run
out under gravity.

The idea of having materials that are hydrophobic is nothing new. What
is new is that they claim to be able to treat standard fibres and make
them hydrophobic without affecting the mechanical behaviour of the
material.

OK, thanks Tim & Ian.

I didn't realise that water stuck to polyester fibres.

The product sounds very useful indeed then.

~PB