Tag Archives: Clothes

The next innovative material for clothes? How about muscles

We wear clothes made from unusual things all the time — you even start to wonder what a “normal” material would be. From plant fibers to plastic to stuff produced by worms, there’s no shortage of raw materials that can be used to make clothes. But researchers are constantly looking for others, with potentially even better properties.

An unusual idea is muscles — or muscle fibers, to be more precise. It sounds a bit odd, but according to a new study, it could be more resilient than Kevlar, at a price that is competitive with other materials? Oh, and it’s also more eco-friendly, and no animals are harmed in the process.

Would you wear clothes made from synthetic muscle protein? Image credit: Washington University in St. Louis.

Cheap, durable, scalable

A belt made from muscle sounds like something straight out of a horror movie, but thanks to the work of researchers at Washington University in St. Louis, it may become real in the not too distant future. The team used microbes to polymerize proteins which were then spun into fibers (somewhat like how silkworms produce silk, but using microbes instead of worms).

The microbes can be engineered to tweak the properties of the protein, and in this case, researchers designed fibers that can endure a lot of energy before breaking.

“Its production can be cheap and scalable. It may enable many applications that people had previously thought about, but with natural muscle fibers,” said Fuzhong Zhang, professor in the Department of Energy, Environmental & Chemical Engineering, and one of the study authors.

No actual animal tissues are needed for the process. Instead, the process starts from a protein called titin, which grants muscles passive elasticity. Adult humans have about 0.5 kg of titin in their bodies.

Titin was desirable because of its molecular size. “It’s the largest known protein in nature,” said Cameron Sargent, a Ph.D. student in the Division of Biological and Biomedical Sciences and a first author on the paper. This makes it very resilient but raises some challenges in producing it.

Surprisingly doable

As weird as it may sound, the idea is not new. In fact, researchers have been toying with the idea of using muscle protein as fibers for a long time — but gathering them from animals is unethical and challenging in many ways. So they looked for another idea.

“We wondered, ‘Why don’t we just directly make synthetic muscles?'” Zhang said. “But we’re not going to harvest them from animals, we’ll use microbes to do it.”

Getting bacteria to produce large proteins is very hard. So instead, the researchers engineered bacteria to piece together smaller parts of the protein into an ultra-sturdy structure. They ended up with a protein with a high molecular weight and about 50 times larger than the average bacterial protein. Then, they used a wet-spinning process, converting the proteins into fibers about 10 times thinner than a human hair.

They opted for a fiber that is especially strong, but the process could be tweaked for any desired property. You could make clothes that are softer or dry quicker, the process can be scaled in any desired direction.

“The beauty of the system is that it’s really a platform that can be applied anywhere,” Sargent said. “We can take proteins from different natural contexts, then put them into this platform for polymerization and create larger, longer proteins for various material applications with a greater sustainability.”

Furthermore, because the fibers are almost indistinguishable from natural muscle, they can also be used in medical procedures, for instance for sutures and stitching up wounds. Unlike other synthetic polymers, this is also biodegradable and less polluting to the environment.

“By harnessing the biosynthetic power of microbes, this work has produced a novel high-performance material that recaptures not only the most desirable mechanical properties of natural muscle fibers (i.e., high damping capacity and rapid mechanical recovery) but also high strength and toughness, higher even than that of many manmade and natural high-performance fiber,” the researchers conclude.

So, would you wear clothes made from muscle?

The research has been published in Nature Communications.

Electronic textiles could turn clothes into wearable electronics

Smartwatches and wristbands have come a long way, but what if you could integrate electronic displays directly into clothing? Researchers in China explored this concept in a new study where they described electronic textiles that can be turned into flexible, breathable, and durable displays.

The ultimate wearable electronics: your clothes

Weaving solid-state display materials into clothing is not only cumbersome and clunky, it’s just impractical. Although there are paper-thin, flexible micro-LED displays out there, they simply can’t withstand the kind of deformation that is expected when fabrics are worn and washed.

Huisheng Peng and colleagues at Fudan University in Shanghai, China, looked at this problem and thought of an obvious solution: just turn the clothing’s textiles into electronic displays.

To this aim, the researchers produced a prototype of a display fabric measuring 6 meters in length and 25 centimeters in width. The display fabric can be integrated with another layer of touch-sensitive fabric for the user interface, as well as a fabric power supply. In this case, the power is harvested from solar energy.

A multicolor display textile exhibiting softness and stability under distortion. Credit: Huisheng Peng.

But first, Peng’s team had to overcome a number of technical challenges. To produce illumination, the researchers weaved conductive weft and luminescent warp fibers while being careful to have a stable interface between these two fiber electrodes with an additional transparent and elastic composite fiber.

Another problem is that the thin active layer needs to be coated uniformly, a challenge that was surmounted with the help of scraping micro-pinholes. “We had thus achieved a continuous and large-scale production of such display textiles,” Peng said.

“Integrating displays into textiles offers exciting opportunities for smart electronic textiles – the ultimate form of wearables poised to change the way we interact with electronic devices, but thin-film displays could not meet the application requirements,” Peng told ZME Science.

“Display textiles thus become necessary to serve to bridge human-machine interactions, offering, for instance, a real-time communication tool for individuals with voice or speech disorders,” the researcher added.

During tests, the researchers demonstrated various applications, such as turning the fabric into a navigation tool that displays an interactive map or as a smartwatch-like tool that sends or displays messages via a Bluetooth connection with a smartphone.

After 1,000 cycles of bending, stretching, and pressing, the electroluminescent units remained stable suggesting that the display fabric could perform well in a real-life use case when constant deformation is expected.

Application scenarios for display textile as real-time location and message communication. Credit: Huisheng Peng.

This is why Peng is confident that these fabrics can come to market soon. He already has opened collaborations with some companies involved in the auto, wearable electronics, and smart clothing industries. “I think the display textiles can be widely used for real applications in this year,” the researcher told me in an email.

Next, the researchers plan to scale up the resolution of their display textile and the intensity of the illumination, while keeping costs low.

“As a new technology in displaying, they may change the way we live in many directions,” Peng concluded.

Set your washing machine on short, colder cycles to save both your clothes and the planet

New research at the University of Leeds together with industry specialists is looking into the effects of laundering on the condition, color, and the amount of microfibre released by our clothes.

Image credits Michelle Maria.

Clothes will last longer if you wash them on shorter cycles with colder water, the study found. This would also reduce the number of microfibers and the quantity of dye the clothes release during the washing process, lessening the impact washing machines have on the environment.

Cold, gentle washes

“We are increasingly familiar with the environmental threat posed by throwaway fast fashion, but we also know that consumers claim their clothes can lose their fit, softness, and colour after fewer than five washes — this means it’s more likely they will ditch them long before they are worn out,” says lead author Lucy Cotton, from the University’s School of Design.

“Using shorter, cooler washes is a simple way everyone can make their clothes last longer and keep them out of landfill.”

The team explains that every load of laundry releases thousands of microfibers down the drain. Most of these eventually end up in the ocean and on beaches, contaminating them for years (or until a hapless sea creature gobbles them up).

In order to better understand how to mitigate the environmental impact of washing machines — and how to better keep those cool threads in tip-top shape — the team performed both laboratory and real consumer testing of wash cycle duration on these factors. They explain that theirs is the first study of its kind to also include customer testing.

The team washed 12 dark and 8 light-colored t-shirts together with white fabric squares to test their color-fastness (i.e. how much of the dye leaks out of the cloth with every wash). They used conventional domestic washing machines and Ariel detergent pods, and compared 30-minute cycles at 25°C and 85-minute cycles at 40°C, both with 1,600 rpm spins, for 16 cycles. The washing machines were thoroughly cleaned prior to the experiment. The team collected the waste water from the experimental washes and analyzed them for microfibre content (these were collected and weighed). A series of chemical analyses were performed to distinguish between the different types of dyes that washed out of the clothing.

The team reports that significantly less color leached out of the t-shirts (up to 74% less dye) that were washed using cooler, quicker cycles, and that dye transfer (from darker-colored to lighter-colored fabrics) also decreased in this case. In addition, colder, faster wash cycles reduced the number of microfibers released by up to 52%.

“Our findings can help tackle the issue of ‘invisible’ plastics in the environment,” says Dr Blackburn, who heads the Sustainable Materials Research Group at Leeds.

“Synthetic microfibres are released every time textiles are washed and account for more than a third of all plastic reaching the ocean. But microfibres from cotton and other natural sources are found in even greater numbers in the sea, and we’re worried about their impact too.”

The findings show how the little choices made by consumers can actively help to reduce the number of microfibers released into the wild. Additionally, the team explains that washing clothes at 20°C rather than 40°C saves approximately 66% of the energy used per load — meaning quicker cycles at lower temperatures help slash both your energy bill and CO2 emissions.

Dr Neil Lant, a Procter & Gamble Research Fellow and co-author of the study, says that modern detergents allow for “excellent cleaning results” even with short washing cycles at a lower temperature.

“It’s well known that these cycles reduce our energy bills and carbon footprint, but our partnership with the University of Leeds is helping us understand how they also slow down the ageing of clothes — keeping us looking smart, saving us money replacing garments and helping the environment,” he adds. “It’s a real win win win.”

The paper “Improved garment longevity and reduced microfibre release are important sustainability benefits of laundering in colder and quicker washing machine cycles” has been published in the journal Dyes and Pigments.

Smart clothes may be right around the corner, thanks to a new fabrication technique

Two seemingly incompatible worlds have been joined together thanks to a new technique which allows weaving sensors and semiconductors directly into clothes.

Knitted fabric illuminated by embedded light emitting fiber. Pictures taken by Greg Hren. Owner: Michael Rein and Yoel Fink.

Even before humans developed a true society, we were relying on textiles to cover our skin and insulate ourselves from the cold and rain. As technology progressed, we used textiles for a wide variety of purposes, from backpacks to packaging, and, of course, more clothing. Now, textiles might be getting a revamp and might go “smart”.

Everyday objects seem to get smarter and smarter by the day. We now have smartphones, smartwatches, even smart homes. But one commodity which has remained stubbornly non-smart are clothes. It’s not like clothes wouldn’t benefit from this — there’s a wide array of potential applications, from health sensors to cool, changing colors — but the fabrication process has remained cumbersome and difficult to effectively apply. Simply put, electrical circuits and textiles don’t normally mix well.

This is where Michael Rain, Yoel Fink, and colleagues, enter the stage. They started with a larger polymer mass containing the semiconductor devices alongside a hollow channel. This material is heated and drawn out, at the same time as wire is spooled into the channels.

“As the preform is heated and drawn into a fibre, the conducting wires approach the diodes until they make electrical contact, resulting in hundreds of diodes connected in parallel inside a single fibre,” the study authors explain.

Light emitting fibers woven into fabrics.Pictures taken by Greg Hren. Owner: Michael Rein and Yoel Fink.

Diodes (either LEDs or photodetecting diodes) are spaced out and once drawn, the resulting fibers can be easily woven into fabrics. The process is inherently scalable, allowing the creation of hundreds of meters of these smart fibers, thus overcoming one of the main problems associated with this type of process. The manufacturing process also provides a pattern to knit fabrics with even more advanced functions — opening up a whole new area of research for smart textiles of wearable technologies.

In an accompanying News & Views article, Walter Margulis, a guest professor at KTH Royal Institute of Technology with 30 years in photonics, explains an application demonstrated by the study authors.

“As a final application, Rein et al. show that, if a person presses a finger against a light-emitting fibre and a light-detecting fibre that are near each other, the intensity of the light collected by the light-detecting fibre varies according to the person’s heart rate. This physiological application of textiles could be used in primary-care settings.”

Essentially, this paves the way for integrating low-cost electronic components into fabrics. Whether or not this becomes common practice will presumably be controlled by economic rather than scientific factors, Margulis says, but it’s easy to envisage practical applications of this technology.

The study “Diode fibres for fabric-based optical communications” has been published in Nature.

Copper.

Copper-coated uniforms for medical staff could help shred bacteria in hospitals

Healthcare professionals might soon be bringing on the bling in the workplace, as UK and Chinese researchers designed copper-covered uniforms to help fight bacteria.

Copper.

Image via PxHere.

Materials scientists from the University of Manchester, working with counterparts from several universities in China, have created a ‘durable and washable, concrete-like’ material made from copper nanoparticles. They’ve also developed a method of bringing this composite to textiles such as cotton or polyester, a world first.

Coppering out

Bacterial infections are a major health issue in hospitals across the world. These tiny prokaryotes spread throughout healthcare facilities on surfaces and clothing, leading to losses both of life and of funds. The issue becomes worse still after you factor in the rise of drug resistance in most strains, which is rendering our once-almighty antibiotics more and more powerless. So we need to look for alternative ways of dealing with them, ones that do not rely on antibiotics.

One increasingly promising set of tools in our fight against disease are precious metals, such as gold and silver, which have excellent antibacterial and antimicrobial properties. However, deploying these on the surfaces and clothing mentioned earlier runs into some pretty obvious problems: first, gold and silver are really expensive — after all, they literally used to be money. Secondly, they don’t lend that well to making practical clothes, especially in a hospital setting.

Enter copper. Less expensive than gold or silver, copper is nevertheless still very good at killing pathogens, which solves problem one. However, up to now, we still didn’t have an adequate answer to issue number two — which is what the team addresses in this paper.

Using a process dubbed ‘Polymer Surface Grafting’, the researchers were successful in tying copper nanoparticles to cotton or polyester using a polymer brush. Cotton and polyester were chosen as a test bed as they’re the most widely used natural fiber and a typical man-made synthetic fabric, respectively.

The materials were brushed over with copper nanoparticles measuring between 1 and 100 nm, which is really small — one nm equals one-millionth of a mm. The metal particles formed a strong, stable chemical bond with the cloth, meaning the metal won’t flake off or be washed away.

“Now that our composite materials present excellent antibacterial properties and durability, it has huge potential for modern medical and healthcare applications,” says lead author Dr Xuqing Liu, from UoM’s School of Materials.

During lab tests, the copper-coated materials easily killed Staphylococcus aureus (S. aureus) and E. coli, two of the most common and infectious bacteria in hospitals, even after being washed 30 times.

The team says their results are very promising, and Dr. Liu adds that “some companies are already showing interest” in developing it further.

“We hope we can commercialise the advanced technology within a couple of years,” he adds. “We have now started to work on reducing cost and making the process even simpler.”

The paper “Durable and Washable Antibacterial Copper Nanoparticles Bridged by Surface Grafting Polymer Brushes on Cotton and Polymeric Materials” has been published in the Journal of Nanomaterials.

Gran-jeans: 6,000-year-old indigo dyed cotton found in Peru

Archaeologists have found the oldest known pieces of indigo-dyed cotton in Huaca Prieta, northern Peru, and it goes to show that a good pair of jeans will last you forever — the materials are at least 6,000 years old.

Photograph of specimen 2009.052.01.B found at the site and reconstruction of the original patterns. This fragment is between 4100 and 3500 years old and has an indigo-blue stripe highlighted with ochre.
Image credits Jeffrey C. Splitstoser et al., Science Advances (2016.)

Huaca Prieta is the site of an prehistoric settlement in northern Peru which was occupied between 14,500 and 4,000 years ago. It is a large stone and earthen ceremonial mound first excavated in the 1940s, which has (repeatedly) produced the oldest known cotton fabrics decorated with recognizable art in the Americas. Recently, an international team of archaeologists found and analyzed eight fragments of cotton textile at the site. The pieces appear to have belonged to bags or containers, most were under one square foot in size, and they were dated to roughly 6,000 years ago in Huaca’s Preceramic period.

Cotton is believed to have been domesticated independently in several parts of the ancient world — such as South Asia or the Middle East — but it probably first happened on Peru’s northern coast, at least 7,800 years ago. Cotton probably saw widespread use in the area by the preceramic period, so finding the material here while unlikely, isn’t groundbreaking. Something else, however, is.

The most striking feature of the textiles are the still-visible dyes used to adorn the weave. Strands of blue-indigo were woven with ochre to create beautiful patterns, some of which are still visible today.

“The textiles were originally very, very dirty,” says archaeologist Jeffrey Splitstoser, an expert in textile structures and co-author of the research paper. “You could see blue in some of the samples but they were mostly grey. You know how your blue jeans fade over time? Well, these were like 6,000-year-old blue jeans.”

The team used high-performance liquid chromatography to identify the dyes‘ make-up. They found plant-based indigo dyes in five of the eight samples, ranging in age from 6,200 to around 1,500 years old.

This predates the oldest known use of indigo-dyed textiles (from the time of Egypt’s Fifth Dynasty and dated to approximately 2400 B.C) by more than 3 millennia.

The cotton used by Peruvians them, Gossypium barbadense, also known as Pima cotton, has since been used to create the mainstay strains used by modern cotton industry, Splitstoser says. So the jeans you’re wearing tight now aren’t very different from these eight fragments — take good care of them, and they might last you 6,000 years.

“South Americans really did contribute to [the history] of blue jeans,” Splitstoser adds.

The full paper “Early pre-Hispanic use of indigo blue in Peru” has been published in the journal Science Advances.

Stanford researchers develop the coolest clothes – literally

Stanford engineers have developed cheap, low-cost textiles that can cool your body much more efficiently than existing clothes.

The clothes can make you feel cooler than wearing nothing at all. Photo by AhmetSelcuk.

Naturally, a logical application for this technology would be in hot climates, especially where air conditioning is not available. But even when air conditioning is available, the cooling clothes could help save a lot of energy. Detailing their work in Science, the researchers explain:

“If you can cool the person rather than the building where they work or live, that will save energy,” said Yi Cui, an associate professor of materials science and engineering at Stanford and of photon science at SLAC National Accelerator Laboratory.

There are two mechanisms through which the material cools the body. The first one is not innovative, and is something that already exists in some fabrics: it lets perspiration evaporate through the material. But the second mechanism is indeed revolutionary: it allows heat that the body emits as infrared radiation to pass through the plastic textile. This means that the wearer feels almost 4 degrees Fahrenheit cooler than if they wore cotton clothing.

The anti-blanket

All existing bodies in the universe give off infrared radiation, which is invisible to the human eye. To easily visualize this, think of night-vision goggles – they see the heat given away by bodies. When you put a blanket on, it doesn’t heat you directly, but it traps the heat you radiate close to you. This material does kind of the opposite, allowing most of this energy to be released.

“Forty to 60 percent of our body heat is dissipated as infrared radiation when we are sitting in an office,” said Shanhui Fan, a professor of electrical engineering who specializes in photonics, which is the study of visible and invisible light.

“But until now there has been little or no research on designing the thermal radiation characteristics of textiles.”

Stanford researchers began with a sheet of polyethylene and modified it with a series of chemical treatments, resulting in a cooling fabric. (Image credit: L.A. Cicero)

While the idea sounds fairly simple, the technology behind it is anything but. The team implemented nanotechnology, photonics, and chemistry to give polyethylene – the common, transparent plastic often used as kitchen wrap – a number of desirable characteristics. For example, they made it allow thermal radiation to pass right through it. The same goes for air and water vapor. They also made it opaque (not transparent).

But people don’t wear plastic, so they had to change it once more. To make this thin material more fabric-like, they created a three-ply version: two sheets of treated polyethylene separated by a cotton mesh for strength and thickness.

Better than wearing nothing at all

The end result was that the clothes keep you cooler than your own skin, which is quite an achievement.

“Wearing anything traps some heat and makes the skin warmer,” Fan said. “If dissipating thermal radiation were our only concern, then it would be best to wear nothing.”

When they compared it with regular cotton, it made the skin surface 3.6 F colder. This might not seem like much, but it can make a huge difference – the difference between turning the air conditioning on or leaving it off, or the difference between making a person feel comfortable or uncomfortable.

The team is now working on making different textures and colors, making it suitable for mass production. The material and the thermal treatment is quite cheap, and it could be suitable for countries in hot climates.

“If you want to make a textile, you have to be able to make huge volumes inexpensively,” Cui concluded.

Nano-enhanced textiles could lead us to a brighter future with no laundry

Tired of laundry day? Pioneering nano research into self-cleaning textiles could soon make cleaning your clothes as easy as hanging them out on a sunny day.

Cotton textile fibers and nanostructures. Image magnified 200 times.
Image credits RMIT University

A team from the Ian Potter NanoBioSensing Facility and NanoBiotechnology Research Lab at the RMIT University in Melbourne, Australia, have developed a cheap and efficient method of incorporating nanostructures which degrade organic when exposed to light directly into textile fibers. Thier new production technology could pave the way for clothes that can shrug off grime and slime when put under a light bulb or worn out in the sun.

When exposed to light, the nanostructures release so-called hot electrons — particles that gain very high kinetic energy after being accelerated by a strong, high intensity electrical field within a semiconductor. These electrons then consume their energy to degrade organic matter stuck in the weave around them. The researchers worked with copper and silver-based compounds to create their nanostructures, as these are known for their ability to absorb visible wavelength intervals of light.

The color red indicates the presence of silver nanoparticles. The image shows a full coverage of the material with nanostructures grown by the RMIT team. Image magnified 200 times.
Image credits RMIT University

Self-cleaning clothes aren’t a new concept. But the RMIT team aimed to develop a method that would allow active structures to be permanently attached to the fibers and be usable on an industrial scale at the same time. Their novel solution was to grow them directly onto the materials by dipping these into a series of chemical solutions. The whole process takes roughly 30 minutes and results in extremely stable nanostructures.

During laboratory tests, it took less than six minutes of light exposure for the nano-enhanced fabrics to spontaneously clean themselves.

Nanostructures grown on cotton textiles by RMIT University researchers. Image magnified 150,000 times.
Image credits RMIT University

“The advantage of textiles is they already have a 3D structure so they are great at absorbing light, which in turn speeds up the process of degrading organic matter,” said Lead researcher Dr Rajesh Ramanathan.

Dr Ramanathan says that the process has a variety of possible applications in catalysis-based industries such as agrochemicals, pharmaceuticals and natural products, and can be easily scaled up to industrial levels.

“Our next step will be to test our nano-enhanced textiles with organic compounds that could be more relevant to consumers, to see how quickly they can handle common stains like tomato sauce or wine.”

“There’s more work to do to before we can start throwing out our washing machines, but this advance lays a strong foundation for the future development of fully self-cleaning textiles,” Ramanathan concluded.

The full paper, titled “Robust Nanostructured Silver and Copper Fabrics with Localized Surface Plasmon Resonance Property for Effective Visible Light Induced Reductive Catalysis” has been published online in the journal Advanced Materials Interfaces and is available here.

 

The original haute couture: archaeologists unearth fabrics from King Solomon’s time

Recent archaeological findings in the Timna region in Israel’s southern Arava Valley showcase the surprising variety and quality of the clothes worn some 3,000 years ago.

If there’s anything my girlfriend has thought me is that I don’t know anything about modern fashion. And she’s right, I’m the Jon Snow of haute couture. But since fashion is something that she can get really caught up in, I thought I’d start from the beginning and learn my way from there — and you can’t really get any earlier that ancient Israel.

Tel Aviv University’s Timna excavation team on-site, setting the earliest trends in fashion.
Image credits Central Timna Valley Project/TAU.

So, what would have been on the catwalk in the days of King Solomon? Recent archaeological findings by a team from Tel Aviv University might answer that question. They uncovered an extensive collections of fabrics in the country’s southern desert copper mines. This is the first discovery of the materials people wore some 3,000 years ago, Israel’s Foreign Ministry reports.

“No textiles have ever been found at excavation sites like Jerusalem, Megiddo and Hazor, so this provides a unique window into an entire aspect of life from which we’ve never had physical evidence before,” said lead archaeologist Erez Ben-Yosef in a statement Wednesday.

“We found fragments of textiles that originated from bags, clothing, tents, ropes and cords.”

Try to imagine an ancient Israeli getup, I’ll wait. Done? The first images to pop in your head are the ones from movies like Passion of the Christ, right? Where everyone is wearing a gray sack with a hole cut out for their head, looking miserable. And even the fancier clothes look like they’re weaved from something so rough it makes your eyes itchy.

And well, probably. But the rich, powerful and influential people of the time had a pretty impressive range of clothing to choose from. Varied materials, colors and models were available to them, the findings show.

A thick goat hair cord made using many threads twisted together for durability and strength.
Image credits Clara Amit/Israel Antiquities Authority.

The fabrics were found in Timna in the Arava Valley of southern Israel, an active mining area around the 10th century BC, during King Solomon’s reign. The colorful artifacts offer unique insight into the attires, but also the trade practices and economy of that period.

Many of the fabrics, including water-intensive linen cloths, were grown and woven far from the mine in which they were found. This hints at intense trade between the Timna region and Northern Israel of the Jordan Valley, with copper exports being used to pay for the daily goods that were required by the community to survive in Israel’s harsh deserts.

“We found linen, which was not produced locally,” said TAU masters student Vanessa Workman.

“It was most likely from the Jordan Valley or northern Israel. The majority of the fabrics were made of sheep’s wool, a cloth that is seldom found in this ancient period.”

Far from the undyed fabrics we’re used to associate with those times, archaeologists found fragments of a surprising variation in color, weaving patterns and ornamentation. One woolen fragment, for example, is dyed red and blue with strands of animal hair woven in to form decorative bands within the fabric.

“We found simply woven, elaborately decorated fabrics worn by the upper echelon of their stratified society,” Ben-Yosef adds.

“Luxury- grade fabric adorned the highly skilled, highly respected craftsmen managing the copper furnaces. They were responsible for smelting the copper, which was a very complicated process.”

Fine wool textile dyed red and blue. The black and orange colored bands are made with naturally-colored wool.
Image credits Clara Amit/Israel Antiquities Authority.

Turns out Hollywood isn’t the best source for accurate historical info (who would have guessed, right?). These fabrics adorned the higher-ups in the society, men with the skill to turn ore into precious copper. The mines themselves were worked by slaves, in harsh conditions and presumably, humbler attires.

“Miners in ancient Timna may have been slaves or prisoners; theirs was a simple task performed under difficult conditions,” Ben-Yosef concludes.

“But the act of smelting, of turning stone into metal, required an enormous amount of skill and organization. The smelter had to manage some 30 to 40 variables in order to produce the coveted copper ingots.”

The findings show the geopolitical and economical importance of the Edomites (the tribe living in this region and working the copper mines) during the time of King Solomon. Supplying a population with water, food and other goods in the middle of the desert raises difficulties even today, and must have been a Sisyphean task with the age’s technological levels.

“Copper was a source of great power, much as oil is today,” Ben-Yosef concludes.

“If a person had the exceptional knowledge to create copper, he was considered well-versed in an extremely sophisticated technology.”

The fabrics are just one part of the larger Central Timna Valley Project, an ongoing effort started in 2012 to explore the archaeological record of the southern Arava’s copper mining and smelting sites. Arid conditions in the area have helped organic materials such as fabric and leather survive.

MIT polymer paves the way for solar-heated clothes

MIT scientists have developed a material that can absorb solar energy, store and release it on demand to produce heat. Made from a film of polymer, the material could be used to used to tailor cold climate garments that charge up during the day and keep you pleasantly warm in the evening.

Image via inhabitat

The polymer weave absorbs energy from the sun’s rays and stores it through chemical reactions within a transparent film. The material contains certain molecules that move into a “charged position” when exposed to sunlight.

Storing energy in a chemical form is desirable as the compounds are stable enough to allow the user to draw on the reserves at their own discretion. The energy from the material can be released with widely available catalysts. For example, the heat stored in a solar-charged jacket can be released when it’s subjected to a powerful flash of light or when exposed to an electrical current.

The team claims the polymer can heat up to 60 degrees Fahrenheit, and it can store solar energy for an indefinite amount of time.

If applied to clothing, the sun-storing material could benefit everyone from athletes or cold-weather workers, as well as regular fashionistas living in chilly environments.

Researchers say the film is easy to produce, in a two step process. They are looking to apply the energy-harvesting film to materials and products like clothing, window glass and industrial products.