Every Fiber We Use, and Why It's There

We don't pick materials because they sound good on a label. Every fiber in a Daruma product is doing a specific job, and we can tell you exactly what it is and why it's there — including the parts that aren't fully natural.

Hemp: structure

Hemp does the heavy lifting in the Hemp Gi, where the fabric has to survive years of grip fighting without failing at the seams. Peer-reviewed testing (Shahzad, 2013, Advances in Materials Science and Engineering) puts hemp fiber's tensile strength at roughly 2–3 times that of cotton at the conservative end of published ranges. Longer fiber length and higher cellulose content are what make that possible — it's not a marketing multiplier, it's fiber structure.

Bamboo viscose: breathability, with an honest caveat

Bamboo shows up in the Pearl Weave Gi (30%, blended with cotton) and does the bulk of the work in our rashguards (95%, with 5% spandex for stretch) and as the inner lining of our grappling shorts.

Here's the part most brands leave out: what's sold as "bamboo fabric" — ours included — is bamboo viscose, meaning the raw plant is chemically processed into a soft, spinnable fiber. That processing is also why we don't market it as naturally antimicrobial. The compound responsible for bamboo's antibacterial reputation doesn't reliably survive the viscose process, and the U.S. FTC has fined multiple retailers for making that exact claim. What does survive is the fiber's structure: bamboo viscose absorbs and releases moisture efficiently, which is what actually keeps it breathable during a five-round session. We'll make that claim. We won't make the antimicrobial one.

Organic cotton: everywhere else, and it's certified

Our 380GSM Lightweight Gi, Black Tenzō Gi, Kids Gi, Noir Edition Gi, and Kondoro Kids Collection are 100% GOTS-certified organic cotton — Global Organic Textile Standard, independently audited from farm to finished garment, not a claim we're making unverified. That certification doesn't extend to the Pearl Weave Gi, whose cotton content is conventional; we'd rather say that plainly than let one certified product imply the whole line is certified.

The one place we use a true synthetic, and why

Our grappling shorts have a recycled polyester outer shell, made from post-consumer PET bottles. Grappling shorts take a different kind of load than a gi — four-way stretch through deep hip movement, constant friction, constant sweat — and natural fiber alone doesn't hold up to that yet without failing early. So the compromise goes where it does the least harm: polyester on the outside, and the same 95% bamboo viscose / 5% spandex fabric used in our rashguards lining the inside, so the only fiber against your skin is the natural one.

It's the one product in our lineup that isn't fully natural fiber, and we're not going to bury that in fine print. Every gi we make has zero polyester in it — full stop. The shorts are the deliberate, disclosed exception, not an inconsistency someone else has to point out.

Made in Portugal

Our organic cotton products are manufactured in small ateliers in Portugal rather than mass-production facilities. Manufacturing in Portugal means EU labor law applies by default, the supply chain is short enough to actually trace, and Portuguese textile mills carry some of the highest combined OEKO-TEX and GOTS certification density in Southern Europe.

The short version

Hemp where structure matters. Bamboo viscose where breathability matters, described as what it actually is. Certified organic cotton where we say it's certified, and only there. Recycled polyester exactly once, disclosed, and kept off your skin. That's the whole material list — nothing more, nothing rounded up.