The Iron Problem In The Non-Iron Process!

The lobby of the Hilton Hotel was impressively spacious, designed with thoughtful attention to detail. On one side, the reception desk welcomed guests, while the centre of the lobby featured an array of rectangular and round tables surrounded by two to four tub chairs. The atmosphere was lively, a dynamic crossroads of people arriving, meeting and departing. On the opposite side of the reception was the lounge.

I was waiting for Fujimoto, with whom I had arranged to visit our customer’s factory in the Nishiwaki area. As I waited, my mind churned over the peculiar problem we were facing. All the latest batches we had supplied were experiencing increased yarn breakages during weaving, even though our test results indicated otherwise. In fact, the yarn strength had shown marked improvement in these recent batches. The severity of the issue had left me with no choice but to make this trip to Japan.

At 7:00 AM sharp, Fujimoto arrived.

“Our bus to Nishiwaki departs from the JR station at 7:35 AM. Shall we head out? It’s about 10-minute walk from here,” he suggested.

“Okay! Let’s go!” I replied.

The bus terminal for Osaka Station was situated on the north side of the station building, just outside the first floor. Since the Hilton was located on the south side, we had to traverse the station from one end to the other. By 7:10 AM, we had reached the bus terminal.

Inside the ticket office, only a few people lingered, yet they maintained a perfectly orderly line. The bus was nowhere to be seen until, with near-perfect precision, it arrived two seconds before its scheduled 7:35 AM arrival time. It was a sleek Volvo bus labeled “Nishinihon.”

We boarded and settled in for the two-hour journey to the Nishiwaki area. During the ride, Fujimoto shared interesting details about Nishiwaki.

Like Bhiwandi and Ichalkaranji in India, Nishiwaki is a weaving conglomerate. It is the production epicentre of yarn-dyed fabrics. There are two rivers in the city that assisted in the development of many industries, including Banshu-ori textiles.

“Banshu-ori textiles mean making of ancient cotton textiles by dyeing, weaving and finishing in one continuous production cycle. The soft water from rivers like Sugihara makes it perfect for dyeing. Now, with the latest computer jacquard technology, they can create patterns as if they are printed, and more functions are added, like non-iron (wrinkle-free) characters.

Soon, we arrived at the weaving factory in Nishiwaki, where the factory in-charge Okamura greeted us warmly at the entrance. After a brief discussion, we proceeded inside to observe the operations firsthand.

I carefully watched the weaving process unfold. The machines operated at a moderate speed, yet within five minutes, a warp-side break occurred. Swiftly, I collected both broken ends and examined them under a lens. After analyzing, I placed the broken samples into a separate bag for further investigation.

After about thirty minutes, we moved on to the processing department, where the yarn was given a wrinkle-free, or “non-iron,” treatment.

This treatment involves modifying cotton at the molecular level using liquid ammonia, which relaxes the fibres and enhances their firmness and gloss. When applied to towel pile yarns, the result is a refined texture with clean and beautifully standing piles.

Wrinkle-free Treatment

Before Processing　　　　　　　　　　 After Processing　for pile

At the process, I noted that the yarn was elongated by approximately 4% before being immersed in cold ammonia at -35°C for 0.3 seconds, followed by infrared drying for 5 seconds.

Suddenly, a label on the floor caught my attention. Upon reading it, a realization struck me.

“Is there a chemical testing lab here?” I asked Fujimoto.

In the lab, I arranged several chemical bottles from the shelves onto the table and conducted tests on the collected yarn samples. I then analyzed freshly broken samples under an electron microscope for additional insights.

Later, back in the meeting room, I shared my findings. “The issue lies with the iron content in the cotton,” I declared.

A chorus of surprised voices responded, “What?”

I explained, “During ammonia treatment, the iron in the yarn reacts to form ferrous oxide, which weakens the surrounding fibres and causes warp breaks during weaving.”

“How does iron end up in the yarn?” Fujimoto asked incredulously. “All textile machinery is made of iron and steel. How can cotton be processed without contact with these materials?”

I replied, “While some iron contamination may occur during the spinning process, I have another theory. I once studied an article about the metal contents in cotton fibres cultivated in different areas. Though the average iron content is around 90 PPM, the recent Indian cotton has an iron content of around 205 PPM, whereas the Egyptian cotton has only around 5 PPM.” I explained.

Kimura chimed in, “Does this mean Indian cotton isn’t suitable for wrinkle-free treatment?”

I held up the label I had found near the continuous mercerizing machine. “This is the solution,” I declared, showing it to everyone.

“What is it?” Fujimoto asked.

I explained, “I confirmed on our way to here with a processing specialist in India that this chemical inhibits iron from reacting with ammonia and forming iron oxide. You’re already using it as part of your standard procedure. My suggestion is to increase its dosage for Indian cotton to prevent warp breakage issues.”

Reassured, the team agreed to test the updated recipe and provide feedback. After my return to India, I understood that this adjustment had resolved the breakage issue.