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Researchers Develop Self-Cleaning Clothes
Ponca City, We Love You writes "Researchers at Monash University, in Australia, have found a process to coat natural fibers such as wool, silk, and hemp that will automatically remove food, grime, and even red-wine stains by coating their fibers with titanium dioxide nanocrystals, which break down food and dirt in sunlight. Titanium dioxide is a strong photocatalyst and in the presence of ultraviolet light and water vapor, it forms hydroxyl radicals, which oxidize, or decompose, organic matter. "These nanocrystals cannot decompose wool and are harmless to skin," says organic chemist and nanomaterials researcher Walid Daoud. Titanium dioxide can also destroy pathogens such as bacteria in the presence of sunlight by breaking down the cell walls of the microorganisms making self-cleaning fabrics especially useful in hospitals and other medical settings."
Sunlight?
This is some new kind of LED, right?
"...natural fibers such as wool, silk, and hemp..." So what if I'm sitting real close to someone who is wearing spandex or nylon or some other artificial fabric? Does it eat through those?
Obviously this would be the perfect clothing for many slashbots. However its requirement of sunlight to activate the self-cleaning enzymes makes it impractical for those basement dwellers among you.
Can they modify the fabric to react to the glow of a CRT?
I guess we'll be seeing many more geeks walking around in their underwear.
...man wakes up to find a pile of goo wearing his wife's very clean titanium dioxide pajamas...
It's interesting that a compound normally used in dyes is now being use to prevent stains.
1) Does this process bleach the fabric? (i.e. Does this work for colors other than white?)
2) What does this do to the longevity of the fibers in the fabric? Does constant exposure to hydroxyl ions damage the cellulose in them?
If it's for-profit but free, you're not the customer -- you're the product (e.g., the Slashdot Beta's "audience").
I guess the old "Spill something on her dress and act concerned by patting her chest with a napkin" plan just flew out the window. Now I gotta use other plans to act innocent while copping a feel.
I guess I could try the "Make a sudden stop at a light right before it turns red and stick my arm out to make sure she doesn't fly forward" plan.
http://science.slashdot.org/article.pl?sid=02/09/19/1246231
What stops the hydroxyl radicals produced by Ti02 from oxidizing the organic material in the cotton, silk, or hemp fibers?
Sounds like a great way to ensure no one wears last year's fashions.
Two wrongs don't make a right, but three lefts do.
Titanium dioxide is non-toxic. You'll just poop it out.
"Titanium dioxide is a strong photocatalyst" meaning it's not used up in the process. It breaks water into an -OH and an H, which in turn clean your clothing. Basically, it'll produce bleach vapor from water vapor when sunlight is hitting it.
-- "At Microsoft, quality is job 1.1" -- PC Magazine, Nov. 1994
Researchers ... have found a process to coat natural fibers ... by coating their fibers...
That's some darn good journalism right there. Uh-huh.
Feb. '08 - Researchers Develop Self-Cleaning Clothes
June '09 - Startup "Washtec" Sells First Self-Cleaning Clothes
Oct. '09 - Old Navy, Nike, UnderArmour License Self-Cleaning Fabric Technology
Nov. '12 - Self-Cleaning Apparel Set to Overtake Ordinary Clothing Sales this Holiday
July '13 - Self-Cleaning Clothes Linked to Cancer, Impotence, Schizophrenia
Aug. '13 - Self-Cleaning Clothes Health Study Flawed
Nov. '13 - Self-Cleaning Clothes: The Killer in your Closet
Nov. '13 - SCCs do Pose Some Risk, Scientists Say
Dec. '13 - SCC Risks Exaggerated, Study Finds
Feb. '14 - Old Navy pulls SCCs from Shelves
June '14 - Newer, Safer, SCC Technology Developed
But what is wrong with this picture (from one of the Wikipedia links above)? Is she some sort or slave woman whose chains were photoshopped from her legs but not all of her shadow? WTF?
Method of processing duck feet
You know that soap will kill you. Also, water is the deadliest substance on Earth, says so right here.
Curiosity was framed, Ignorance killed the cat.
Not only that, but your skin is crawling with "good" bacteria and how does it know the difference between the "bad" bacteria to break down and the "good" bacteria on your skin?
Beer is proof that God loves us and wants us to be happy.
Any very fine mineral dust you inhale in large quantities -- and 5.0 grams per cubic meter is unbelievably dusty, like blowing a whole pack of chalk to smithereens in your office -- will cause the symptoms described in both the OSHA document and the more problematic document you cite from people who want to scare you into buying their (more expensive) "natural" products.
All particles with sharp edges, i.e. that come from minerals, irritate the delicate tissue lining your lungs if you inhale it. TiO2 is no different in this regard than, say, SiO2 -- plain old sand -- that you might inhale if you were around blasting or power sanding operations all day. (Google "silicosis.")
Furthermore, your lungs are built like lobster traps from the point of view of inhaled superfine particles: it's easy to get in, but very difficult to get out. This is why in the upper region of the respiratory tract, you have mucus that traps inhaled larger particles and cilia that beat constantly to flush them up and out, plus a cough reflex to expel the scum. But you can't have these things in the deep tissue of the lungs, because that surface area is needed for gas exchange.
So if you inhale very fine dust, it just stays in your lungs pretty much forever, jiggling around and rubbing on things, irritating them. Your body may decide to wall it off with scar tissue if it's irritating enough, which is the "fibrosis" mentioned. It's even possible if it's sufficiently irritating, like the very sharp particles of asbestos fibers, that it can stimulate lung cancer. For all we know, the only reason people get lung cancer in the large numbers they do is because, sooner or later, everyone's lungs fill up with irritating particles of all manner and description and the chronic irritation causes tumors. Unfortunately, the only way to eliminate the threat of inhaled fine dust completely is to never breathe without a heavy fine-filtering face mask.
Insofar as these clothes are concerned, the primary question would be: how is this very fine dust going to be generated? I mean, inhaling very fine silica (SiO2) dust is dangerous in exactly the same way, but you don't refuse to go to the beach or rock-climbing because you know the rock and sand has no reason to suddenly pulverize itself and become superfine dangerous dust. So how would fibers coated with TiO2 get pulverized and generate super fine dust? Don't say the motion of wearing the clothes, either, because you need much more force than this. Walking on the sand at the beach doesn't pulverize the sand particles and generated dangerous superfine silica dust, after all.
It's not hard to keep the red shirts clean--people don't seem to wear them very long.
There's actually a pretty subtle distinction here. "Superbugs" are caused by the overuse or misuse of antibiotic medicines -- chemical agents that selectively kill bacteria and other germs. Less-subtle techniques, like most antiseptics, are much tougher to develop a mechanism for avoiding, so topical antiseptics like soap and bleach stand no real chance of becoming ineffective germ-killers. (They're also not selective, and so doing something like ingesting them is not feasible.) While putting antibiotics into products unnecessarily increases the risk of developing an antibiotic-resistant bacterial strain, this isn't the case for an antiseptic (like what is produced by TiO2).
There was a great movie about this subject made in the 50's called "The Man in the White Suit", with Alec Guinness. In the movie, a scientist invents a fabric that repels dirt and doesn't wear out. After initially being heralded as a hero, all the vested interests (pun unintended) in the world's textile and clothing industries think it will mean the end for them, and they want him dead. The movie might take on renewed relevance...
http://en.wikipedia.org/wiki/The_Man_in_the_White_Suit
http://www.imdb.com/title/tt0044876/