Report May 2025
It’s been another hectic month. Two weeks spent in Japan, meeting an Australasian distributor, and negotiating with potential East & South East Asia distributors. We also picked up an internationally recognised major Kinbakushi as a rebranded OEM customer, who has grand plans for the future, and several others all seeking better rope without JBO.
There was an unexpected award ceremony, where I became certified by the Japanese rope manufacturing industry as a Nawashi. This for all my efforts over the past two decades in researching and developing jute rope designed specific for the purpose of prolonged human skin contact with safe suspension loadings. I’m told I am the first non-Japanese to achieve this.
Critically, our Japanese rope manufacturing corporation partner gave their green light to the final phase of prototype development to produce the target rope quality. The light is now getting brighter at the end of this long tunnel. We can’t go into too much detail because it is a Trade Secret, but suffice to say it should eliminate fibre loss, hairiness and nap, strengthen the product, add lustre, sheen and colour depth, prolong use with greater wear abrasion, and also add heft. On returning to the office, all the engineering drawings have to be completed, and go to machinery manufacturers for tender. Our goal is to introduce the rope it will produce by end-2026.
“The man who never alters his opinion is like standing water, and breeds reptiles of the mind.” – William Blake, The Marriage of Heaven and Hell (1793). We think we know everything about jute fibre and the industry, but in truth we learn something new every day, and have to adjust prior beliefs. Many know things only specific to their market and applied use. Little is published. There are no standards in the industry.
We’re opening up a totally new usage, and completely alien to anything jute growers, yarn mills and rope manufacturers have encountered before. Nobody has ever developed product specific for our intended use on this scale. Since stocks of hemp ran out in Japan during the 1980s and 90s, first Suma Toshiyuki and Nureki Chimuo began finding jute intended for farms in general rope stores, and now everyone in Japan uses jute apart from a very few who still cling to cotton. In discussion with Aotsuki, Bingo, Kinoko, Zima, Kitagawa, Kei, Otonawa, etc., it was interesting how they view the few practitioners who use Chinese-made horticulture JBO jute rope as amateurs. Maybe because it’s dirt cheap, which reflects its quality. They complain if they buy it, they have to throw half of it away because it’s unusable, and the processing effort too much effort for the result. The preferred supplier had been Nawaya, but suffers since their manufacturer ceased trading due to the death of the producer and closure of their company.
Jute is a coarse multicellular bast fibre made up of cellulose building units called ‘ultimate cells’, each ~ø18µ x ~2.5mm. These cells ‘cement’ together during growth to produce filaments that can be as long as 4 meters, taken in bundles from the cortex of the jute plant stem growing from the cambium around the pith. In Corchorus olitorius (Tossa) this is effectively like a straw, sucking water up from the roots. Each cell is made up of a porous hemicellulose wall containing middle lamella and a central lumen void, and it’s the lamella that provides the strong hydrophilic behaviour, acting like sponge.
The hydrophilic nature of jute is why we use wax in our treatments, because it, on its own doesn’t get sucked through the hemicellulose walls so readily. While water will be sucked in at ~22% by volume, speed increasing with temperature, oil:wax mix will take much longer. Which is precisely why your rope will begin to feel dry again some time after processing and coating. Many use beeswax, which will feel sticky. The trend has been to switch to berrywax (Japan wax, Mokurō, Sumac wax) because it’s vegan and produces a better, silky feel.
We visited the Mokurō factory in Japan and learned a great deal. While the Japanese Hazenoki tree grows all over East Asia, high labour costs for collecting the fruit in Japan now means it all comes from China. The wax is pressed from the berries harvested between October and December. Early pickings produce a green wax, changing later with ripening to a colour close to that of high-quality jute fibre. On its own it’s subject to oxidative degradation rancidification. But blending with oil prevents this. Most industrially available wax will have been filtered and processed to off-white pellets for use in cosmetics, which is very expensive. We’re fortunate in that we can procure in unfiltered, unprocessed blocks direct from the factory, because we’re going to be doing our own filtering and blending anyway.
As fibre passes through the manufacturing process, and then used as rope, individual and clusters of the ultimate cells and filaments break off to produce everything from extremely fine dust to hairs. Most come out. Some remain stuck within the compacted twists of the yarn, strands and rope to produce hair which most users in our market will blue-flame singe. However, you’ll note with use they continually return.
The goal therefore, was to find a non-allergic plant-based medium to effecively ‘gum’ these by adding a thin-film around the porous hemicellulose wall. This in turn blocks the hydrophilic action of the middle lamella. But it also makes the resultant yarn feel slightly stiffer.
Dosing in-line at 120m/min, loose fibre and hairs are ‘gummed’ into the yarn. It’s contact polished and dried to produce a very tight count variation (the yarn diameter tolerance). It then enters a secondary plant-based conditioning to re-soften, again with only a thin-film coating, producing a final super-polish, and minimising oil:wax consumption. The result is a single-size, perfectly formed yarn that can be twisted in various numbers to produce different strand and rope diameters that feel like silk.
Of course, we cannot yet know the full cost of doing this process. But switching over to our own in-house yarn production, we aim for it to be roughly the same cost as the current product. And as with every part of this development, as we find anymore supply, production and logistic cost savings, we’ll be passing them on to you, the buyer.
