Stronger Than Steel: The Amazing Spider Web; Jap startup has produced an artificial spider thread that it claims is equal to steel in tensile strength yet as flexible as rubber

July 8, 2013, 8:08 p.m. ET

Can Spider Web Be Replicated? A Japanese Startup Thinks So.

Recreating the Silk of an Arachnid Could Produce the Most Durable of Fabrics

Spiber says its thread is spun into fabric that equals steel in tensile strength yet is flexible like rubber

Spiber bioengineers bacteria with recombinant DNA to produce spider-thread

MAYUMI NEGISHI

Centuries before Spider-Man, people sought to harvest spider silk, a fiber that is so uniquely powerful it not only catches prey but could serve as a highly durable fabric. Pulling thread from an arachnid, however, is painstakingly slow. And putting too many spiders in close proximity makes them territorial and inclined to kill one another. Now, a Japanese startup called Spiber Inc. said it has produced an artificial spider thread that it claims is equal to steel in tensile strength yet as flexible as rubber. The company hopes to spin enough of the thread for mass production within two years, potentially opening the door to creating lighter but stronger auto parts, surgical materials and bulletproof vests. “Spider thread is amazing material—it’s so light, yet so strong and flexible. It can absorb so much energy,” said Spiber President Kazuhide Sekiyama, who came up with the idea to replicate spider thread in college during an all-night drinking session talking about “bug technology.”A key test is how strong Spiber can make its thread in mass production—a hurdle that has stumped researchers in the past. Spiber says it also needs to experiment with different ways to treat the spider thread to protect it from the elements including possibly coating the fibers with resin. Like all organic matter, Spiber thread breaks down eventually.

Spiber aims to produce one metric ton, or 2,205 pounds, of spider silk in 2015. By November, it aims to triple its current monthly output to about 220 pounds.

Dubbed Qmonos—literally, “spider web” in Japanese—Spiber’s thread is the latest example of biomimicry, a field of science that seeks to replicate how things work in nature to solve human problems. Successful examples include Swiss engineer George de Mestral’s invention of Velcro in 1941 from seeing a burr stick to his dog and, more recently, Japan’s Nitto Denko Corp.’s 6988.TO -3.73% development of an adhesive that works in super- high temperatures after analyzing how a gecko’s foot sticks to surfaces.

Spider silk has long been the Holy Grail in biomimicry. Spider thread can be stretched 40% beyond its original length without breaking. Stronger than steel and bone at the same weight and twice as elastic as nylon, a spider web made of strands as thick as a pencil would be strong enough to stop a jumbo jet in flight, some experts say. For centuries, it was gathered and used as fishing line for its elasticity or to dress wounds for its antibacterial properties.

Many have tried to solve the riddle of recreating spider silk. One promising venture was Montreal-based Nexia Biotechnologies, which engineered goats to produce milk containing spider’s silk. The company, which raised $42.4 million in an initial public offering in 2000, folded in 2009 when it failed to make its research commercially viable.

“Spiber’s success hinges on how close its thread is to the real thing,” said Shigeyoshi Osaki, a professor of medicine at Nara Medical University who collects spider thread and showed how a four millimeter-thick piece of string made up of 190,000 strands of spider dragline could support his weight.

The molecular structure of spider-silk protein is complex and long. This gives the thread its ideal balance of elasticity and strength, but it makes replication challenging and costly. Companies might be able to replicate parts of the protein, but the protein’s molecular structure is what gives spider thread its toughness, Mr. Osaki said. Spiber doesn’t disclose detailed data on the composition of its thread.

proteins, and then isolates those proteins into a fine powder, which can be pushed through a hollowed-out needle tip to form wispy thread. One gram of the protein produces about 5.6 miles of silk.

Spiber said it solved a problem flummoxing scientists for years—how to replicate the spiders’ spinning action and figure out the mystery of how their spinnerets work—by making the threads its own way.

Its technique is to bioengineer bacteria with recombinant DNA to produce spider-thread proteins, and then isolate those proteins into a fine powder, which can be pushed through a hollowed-out needle tip to form wispy thread. One gram of the protein produces about 5.6 miles—roughly the height of Mount Everest—of silk.

Since going public with its production technique last August, Spiber said it has received more than a hundred requests to collaborate on projects. With a 750-million-yen ($7.6 million) investment from auto-parts maker Kojima Press Industry Co., Spiber broke ground on a prototype center and pilot plant in the northwest Japanese city of Tsuruoka earlier this month.

Spiber said possible automobile applications include tires, bumpers and electronic parts. In medicine, the company sees the fibers creating products requiring flexibility, such as artificial blood vessels, dissolvable sutures and artificial ligaments.

But it will face competition from Germany’s AMSilk GmbH, which says it plans to scale up lab production of the spider-silk fiber it calls Biosteel. Its product also is made entirely from recombinant silk proteins that are processed via a spinning apparatus to recreate the structure of spider silk.

Another competitor is Michigan-based Kraig Biocraft Laboratories Inc., KBLB +1.35%which says it has genetically engineered silkworms that spin silk containing spider fiber. A small amount of spider protein can strengthen the normal silk produced by silkworms, it said.

Spiber—which is capitalized at 780 million yen with funding from Japan’s Ministry of Economy, Trade and Industry, Keio University and Yamagata prefecture, where its factory is located—said it has the advantage of speed.

It said it can design a new spider thread with different capabilities in as little as three days, and already boasts a stock of 250 different types of spider threads that it can make.

Real spiders have about seven. A collection of different thread types—tough, elastic, or sticky—would mean a wider range of applications.

“We’ve finally reached the starting line,” said Spiber’s Mr. Sekiyama. “But at least now we have clear visibility. We know exactly what we need to do from here.”