I’ve got a query relating to glass surfaces. I’ve noticed that glaziers can fit special non-reflective glass to picture frames. I’ve felt the surface of this special type of glass, and it is very very slightly rough. It is perfectly clear and the picture can be seen perfectly, but there is no glare or reflection visible. I wanted to know whether or not this special type of non-reflective glass "fogs up" in warm humid conditions. Perhaps the slightly rough surface may prevent condensation forming? If a mixture of ultra fine glass bead powder and clear acrylic lacquer (and lacquer thinners) was sprayed evenly on a glass surface, this would result in a very fine rough surface. Could this possibly prevent fogging/condensation on the surface?
On Jul 15, 12:36 pm, Gas Bag <shazl...@yahoo.com.au> wrote:
> I’ve got a query relating to glass surfaces. I’ve noticed that > glaziers can fit special non-reflective glass to picture frames. I’ve > felt the surface of this special type of glass, and it is very very > slightly rough. It is perfectly clear and the picture can be seen > perfectly, but there is no glare or reflection visible. > I wanted to know whether or not this special type of non-reflective > glass "fogs up" in warm humid conditions. Perhaps the slightly rough > surface may prevent condensation forming? If a mixture of ultra fine > glass bead powder and clear acrylic lacquer (and lacquer thinners) was > sprayed evenly on a glass surface, this would result in a very fine > rough surface. Could this possibly prevent fogging/condensation on > the surface?
Rough-surfaced glass isn't glare-free: it just distributes the glare over a larger area, making it less obnoxious. And I doubt it has any effect at all on condensation. Anti-reflection coatings do a better job of glare-reduction.
"Fog-free" mirrors are very, very thin and lightweight: the intent is that they will always be at the same temperature as the air and therefore moisture won't condense on them. They work so-so.
"Anti-fog" treatments for glass apply a thin, waxy layer to the surface which is highly hydrophobic (e.g. "rainex"). This works better if the surface is rough, too (on the right scale). This may be what you were getting at, but I am not aware of any permanent treatments of this type.
Jim Deutch (JimboCat) -- "I meant it kept the rain off the face , which umberallas dont do very well because mainly the rain in the Northern Hemisphere falls at greater angles the further north you go" -- Habshi
"Gas Bag" <shazl...@yahoo.com.au> wrote in message
news:fa7cec43-f659-4bfb-8fb1-a81eb976d8fa@c36g2000yqn.googlegroups.com... I’ve got a query relating to glass surfaces. I’ve noticed that glaziers can fit special non-reflective glass to picture frames. I’ve felt the surface of this special type of glass, and it is very very slightly rough. It is perfectly clear and the picture can be seen perfectly, but there is no glare or reflection visible. I wanted to know whether or not this special type of non-reflective glass "fogs up" in warm humid conditions. Perhaps the slightly rough surface may prevent condensation forming? If a mixture of ultra fine glass bead powder and clear acrylic lacquer (and lacquer thinners) was sprayed evenly on a glass surface, this would result in a very fine rough surface. Could this possibly prevent fogging/condensation on the surface?
There are products out there that do that, google for it. hint: it is a liquid.
In article <914251c0-b155-4d83-b1eb-8e381292a...@f30g2000vbf.googlegroups.com>,
JimboCat <103134.3...@compuserve.com> wrote: > Rough-surfaced glass isn't glare-free: it just distributes the glare > over a larger area, making it less obnoxious. And I doubt it has any > effect at all on condensation. Anti-reflection coatings do a better > job of glare-reduction.
All I can add is that the use of this glass has the rough surface close to the picture. If there were a big gap, contrast would be lost. With a small gap, the scattered light seems to come from where it would be scattered by the picture surface anyway, It does mean that a picture with glossy features would be degraded.
Bill
-- Most people go to college to get their missing high school education.
Thanks for your reply…..and all the others. I’m well aware there are a whole variety of anti-fog liquids/gels/waxes available. In fact there’s a particular brand that I use for masks/goggles - it’s absolutely amazing, and I swear by it. (I’m more than happy to let you know, but I don’t want to seem like an advertisement for them) But what I’m trying to do is achieve a permanent effect that is 100% effective; there already is some technology out there that does exactly that. Take a look:
As fogging on glass/plastic surfaces is caused by water’s surface tension, I thought perhaps a very slightly rough surface might help break the surface tension of the tiny water droplets. I’m guessing probably not, but there’s no harm in asking.
> Thanks for your reply…..and all the others. I’m well aware there are > a whole variety of anti-fog liquids/gels/waxes available. In fact > there’s a particular brand that I use for masks/goggles - it’s > absolutely amazing, and I swear by it. (I’m more than happy to let > you know, but I don’t want to seem like an advertisement for them) > But what I’m trying to do is achieve a permanent effect that is 100% > effective; there already is some technology out there that does > exactly that. Take a look:
> As fogging on glass/plastic surfaces is caused by water’s surface > tension, I thought perhaps a very slightly rough surface might help > break the surface tension of the tiny water droplets. I’m guessing > probably not, but there’s no harm in asking.
If it is a hydrated silicate surface you monolayer it with a reactive silane, RSiX3. -X is typically -OMe or -Cl. R is typically a three atom spacer then a quaternized ammonium with counterion. That drastically reduces the surface tension and water sheets not fogs. Presumably a PEO or poly(vinylpyrrolidinone) oligomer tail would also the job.
Rain-X takes the opposite tack. Now R is a silicone oligomer and the treated surface is hyperhydrophobic. Water violently beads but a breeze blows it off. Very nice for windshields - your wipers glide across the surface if you need them at all. After treatment, lightly burnish the surface, wipe with rubbing alcohol, and burnish again. That gets rid of most of the residual goo.
One wonders why competition swimmers don't "condition" their skin with hydrophobes. Uncoupling the otherwise wetted surface would substantially decrease friction.
> Rain-X takes the opposite tack. Now R is a silicone oligomer and the > treated surface is hyperhydrophobic. Water violently beads but a > breeze blows it off. Very nice for windshields - your wipers glide > across the surface if you need them at all. After treatment, lightly > burnish the surface, wipe with rubbing alcohol, and burnish again. > That gets rid of most of the residual goo.
> One wonders why competition swimmers don't "condition" their skin with > hydrophobes. Uncoupling the otherwise wetted surface would > substantially decrease friction.
Now that everybody knows, we should expect pre-competition exams by forensic dermatologists at Olympic swim meets.
> (snip) >> Rain-X takes the opposite tack. Now R is a silicone oligomer and the >> treated surface is hyperhydrophobic. Water violently beads but a >> breeze blows it off. Very nice for windshields - your wipers glide >> across the surface if you need them at all. After treatment, lightly >> burnish the surface, wipe with rubbing alcohol, and burnish again. >> That gets rid of most of the residual goo.
>> One wonders why competition swimmers don't "condition" their skin with >> hydrophobes. Uncoupling the otherwise wetted surface would >> substantially decrease friction.
> Now that everybody knows, we should expect pre-competition exams by > forensic dermatologists at Olympic swim meets.
they tried this in the America's Cup sailboat races, along with something akin to sharkskin riblets, but those ideas were quickly banned.
>> Rough-surfaced glass isn't glare-free: it just distributes the glare >> over a larger area, making it less obnoxious. And I doubt it has any >> effect at all on condensation. Anti-reflection coatings do a better >> job of glare-reduction.
>All I can add is that the use of this glass has the rough surface close >to the picture. If there were a big gap, contrast would be lost. With a >small gap, the scattered light seems to come from where it would be >scattered by the picture surface anyway, It does mean that a picture >with glossy features would be degraded.
>Bill
I thought so. When I was fooling around in photography I didn't like the effect of the glare-free glass.
It should be cheap enough to get a readymade frame with some of this glass and experiment with it.
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