Report August 2026
As a user for shibari, I travelled a very long path to understand jute asanawa. Initial awful product from Tokyo sex shops a quarter century ago, to supply of wonderfully processed sets from kinbakushi friends in Osaka, a short period when Bingo found a few spools of exceptional product, sadly its source never discovered, I then had to turn to cheap, Chinese–made JBO–laden farm rope from high street general rope stores in Tokyo and Kyoto.
Unsatisfied, and knowing I was a development engineer, Ero Ouji and Bingo pushed me to try to find that glorious rope again. Naïvely, I thought I’d find it off the shelf. Years later I discovered it was made with a process for a market by a mill, and neither still existed. The quest was on to replicate, hopefully even better it.
Tying many partners regularly, with the courtesy of each having a dedicated set for reasons of hygiene, and because their skin oil helps polish the rope, over the years I’ve prepared hundreds of batches, with continual experimentation in conditioning.
As consulting engineer to our manufacturing partner, having our own state–of–the–art mill allowed me to get in, understand the production of yarn and rope, and the biochemistry of the fibre.
Jute is a cellulose structure: porous hemicellulose lignin walls providing strength, rigidity and resistance to rot enclosing a spongy middle lamella surrounding a void; the lumen. The higher the fibre quality, the more absorbent the lamella. This is what produces the strong hydrophilic action, and the compressibility providing softness.
When conditioning medium is applied, far slower than with the viscosity of water, it absorbs through the hemicellulose, making the rope feel dry again over time. Experimentation has sought to address this, and we believe we’ve made a significant improvement.
Terminology can be confusing – berrywax, mokurō, Japan wax and sumac wax are all the same thing.
For ø6.0mm SHIZEN we used 0.9g butter per meter rope in each of 2 conditioning runs. ø5.5mm 0.8g and ø5.0mm 0.7g. We mixed by weight, discounting specific gravity. First run with 70:30 jojoba oil:berrywax frozen so it’s stable to handle.
Frozen butter is broken up into small pieces and placed in with loosely coiled rope. We don’t knot the ends at this stage, but use Tesa Extra power tape tightly wound. We then tumble on max. heat for 30~40 minutes.
Rubbing, or allowing rope to smash loose in a tumble dryer is a cause of increased hairiness and fibre loss, and we see the effects in the dryer filter. When tumbled inside a cotton laundry bag i) far less butter is lost out of the dryer exhaust, ii) more is infused into the rope, and iii) because rope isn’t bashed about in the dryer, after a cycle there’s hardly any loose fibre in the filter.
We then took the infused rope out, re-coiled, put it back in the laundry bag and inverted the butter mix 30:70 oil:wax and repeated tumbling at same settings, sealng the surface with wax and inhibited it drying out over time. Note: ensure butter is well broken up, as large pieces won’t fully melt in the hot air stream.
Now noticeably less hairy, a quick blue flame singe helps wax melt in and burn off remaining hair. After hanging to air we finally cut the tapes off and made end knots.
The rope did feel stiffer at first due to the wax coating. But two uses and it quickly softened, held its twist definition much better, which makes the lovely deep rope marks on the skin, and loosened its lay a little.
If you try it, please let us know your impressions.