Prise winners list

The world's smallest needle and thread enable suture of a 0.1mm blood vessel, advancing the surgical operation

Ichikawa-City, Chiba Prefecture
KONO Seisakusho Co., Ltd.
Other award winners
Chikara Iwadate, Satoko Udeda, Seiichi Hisaya, Keisuke Matsumoto
Recommended by
Chiba Prefecture's Commerce, Industry and Labor Dept., Industrial Promotion Section

Kono, Junichi  (46)

This surgical needle that costs 10,000 yen is disposed of after it is used once. If its cost can be reduced, it is meaningless for us to manufacture it

The microsurgery has developed with development of an operating microscope, ultrafine thread and needle. In 2000, the standard thickness of needle was 0.1mm but doctors needed a smaller needle. In a bid to meet their needs, KONO Seisakusho Co., Ltd. started development of a needle of 0.03mm diameter and 0.8mm long and a thread of 0.012mm diameter and completed them in 2004. This company performed all the works for this development except for the thread and the raw material of needle. Subsequently the company developed also a needle of 0.04 to 0.08mm. With these ultrafine needles, threads and peripheral instruments developed, many diagnosis and treatment departments started to conduct microsurgery. Currently this company is trying research and development for more than thirty projects, and further advancement of medical technology is expected.


Reduced from 0.1mm to 0.03mm at once. The world's smallest needle and thread that are widely used in the microscopic world

The microsurgery is a surgery conducted by doctors with a microscope. Its technology has developed because of astonishing dexterity of human hands and the surgical needles becoming smaller and thinner. Currently the smallest needle has a diameter of 30m (micron meter), namely 0.03mm, and a 0.8mm length (an ordinary needle has a diameter of about 0.5mm and a length of about 15mm). Kono Seisakusho Co., LTD. that manufactures this needle is known in its brand name "Crownjun" in Japan and foreign countries. 
"The diameter of the conventional needle for microsurgery was 0.1mm and could be used for a surgery of a tissue in size of up to 0.5mm. With this needle, doctors started to devise various types of microsurgery."
About ten years ago, Mr. Kono was asked by a professor, "Can you manufacture a needle that can suture a tissue of less than 0.5mm (a surgical needle provided with a thread)?" He was worried.
"Everything was unknown. If addition, if a new microsurgical needle and thread are developed, other surgical tools, microscope and peripheral equipment must be developed according to the size of the needle and thread. I thought that the risk was high." 
However, he accepted this request and targeted development of a needle of 0.03mm diameter. The material was a special stainless steel that had good rigidity and tenacity. However this steel was like a bundle of soft cotton when it was a raw material. First of all, we had to start with development of a method to extend each piece straight. Subsequently we cut those wires, sharpened their tips, bent and electropolished them. It was also important to design the shape of needle properly.
"It is easy to manufacture a long needle, but it is not easy to use a long needle for surgery because it easily bend. The maximum allowable length is 0.8mm for a needle of 0.03mm diameter because a surgical needle is a 'blade' that absolutely must not bend or break."
It was also very difficult to connect a needle and a thread. We had to split a needle of 0.03mm diameter into two, insert a thread between the two and swage the needle. We completed the smallest needle and thread in the world in 2004 after three years of research and development. In addition to the needle and thread, we developed and manufactured all the manufacturing equipment, machine tools and jigs for ourselves. These needle and thread enabled anastomosis of a nerve and blood vessel of 0.1mm and operation of a 0.05mm tissue, and so the microsurgery advanced drastically. They enabled precise suture of thin blood vessels, nerves and muscles in transplant surgery of muscles and skin and in operation of re-jointing a cut-off finger.

"They enabled patients to regain not only the appearance but the functions. The thin and soft blood vessels of an infant can be also sutured with these new needle and thread without fail. In addition, patients can recover sooner because their operated area is smaller. Thus the small needle and thread are very useful for the minimally invasive surgery (physical and metal burden is small)."

Small and medium-sized companies are not mere backseat players. They should play a major role in the world's niche market where they can contribute to a society

There are many big manufacturers of medical supplies, but they do not develop these small needles and threads because there is not a big market for a 0.03mm needle and thread. However, "the market is small for a commodity" does not mean that the importance/necessity of that commodity is also small. 
"There are cases where an instrument necessary to save a life is not commercialized because there are only "few patients". However, in such a niche market where we can contribute to a society, we, small and medium-sized companies, can find the significance of our existence."
If we manufacture a product, we will try to manufacture an "excessive quality" product. We must produce such a high-quality product that people appreciate it highly and willingly pay for it. Otherwise, the overseas manufactures will catch up with us very soon. Actually the price of one 0.03mm needle and thread is 10,000 yen. People are ready to pay that amount for one consumable needle and thread which is disposed of after it is used to suture a blood vessel. However, more than thirty work processes are necessary to manufacture one needle, and this is the secret for manufacturing of a unique product with special function and very high quality. This company owns its every know-how for all the processes to keep its development ability and corporate independence. 
"While having a business negotiation overseas, we often find that "Made in Japan" is the brand for good quality, and foreigners often say, "Why don't you make use of that brand?" 
Generally Japanese small and medium-sized manufactures are so absorbed in monodzukuri. In some cases, although they have high technology useful in the world, they are satisfied with being a subcontractor for a big manufacturer and even acquired by a foreign company. Mr. Kono has a sense of crisis for that fact. 
"In monozdukuri, Japanese small and medium-sized companies can compete with foreign manufactures in the world. We appreciate the prize awarded to us this time because we have proven that fact and wish our government support us also for 'the activity beyond monodzukuri'.
His way of thinking is that of a venture business entrepreneur rather than that of a president of small company. Actually Mr. Kono always says to his employees, "We are still a venture company operating for sixty years."

KONO Seisakusho Co., Ltd.

May. 1970 (started in 1949)
10 million yen
90 (as of Dec. 2009)
Brief information:
This developing venture company manufactures various high-value added medical instruments and tools such as ultrafine surgical needles in small quantity in its integrated production system.

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A thread is being connected to a needle. In most cases, however, naked eyes cannot see them.


This cutter splits a needle of 0.03mm into two vertically. A needle is set in the lower groove. (Micrograph photo)


"Needles and threads connected together"


For a slightly larger needle, an extra fine drill or a laser beam is used to drill a hole for mounting a thread.


L: This company manufactures all the manufacturing equipment, tools and jigs for itself.
R: All the surgical instruments for the microsurgery are manufactured by this company.