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Quality "NK assurance, management system that produces quality"

Why is NK so often commissioned by many global brands and companies, despite being a latecomer manufacturer and processing company?

There are various efforts as a latecomer, and they appear in "NK's processing technology and purpose" and "value chain construction standards", but as with many Japanese companies, quality is the first priority. It's nothing but because I want it every day with a strict attitude.

Even with a small number of employees, NK thoroughly adheres to the principle of double checks, a commitment to yields that do not lead to waste, and an attitude of daily education and learning. At the same time, we are all trying to optimize the working environment so that our employees can demonstrate their abilities to the fullest. In particular, we have stipulated two types of major regulations, "Management methods and procedures in quality assurance" and "Important inspection regulations in the sewing process", and shared them with all employees to maximize the capabilities of each employee and We aim to maximize the quality of our products and achieve both.

Here, we introduce NK's "Management Methods and Procedures in Quality Assurance".

Selection of materials "recycled materials"

NK selects and proposes the most suitable materials according to various conditions, such as consumer products and industrial materials, so that customers can use them carefully for a long time.

On the other hand, the “optimal material” can only be said to be optimal for all stakeholders only when we carefully consider what is optimal at the time. All kinds of stakeholders include “diverse natural environments,” “regions where raw materials are procured and the people who work there,” and “societies to which our customers belong.” Based on these, NK emphasizes the following three points in selecting the most suitable materials and in manufacturing.

- At least 50% recycled materials are used.
(For polyester, compared to virgin materials produced from crude oil drilling, refer to various statistics showing that the CFP* reduction rate is 50% or more by using mechanically recycled materials.)


・Environmental standards and quality standards in the material production process are certified by a reliable third party.


・Propose material selection and product design that enable the customer to recycle the product after use.

(In this regard, Toray Ultrasuede is not assumed. This applies to bags made of 100% recycled polyester fabric.)


*CFP (Carbon Foot Print)


Material selection "animal leather"

Animal leather is a historical material that has been used in Japan for more than 1,000 years, and it is also a clothing material that is said to have been used by ancient Neanderthals to protect against the cold. On the other hand, in recent years, in the global penetration of SDGs after 2015, it can be said that it is an important theme that can directly or indirectly encompass all of the 17 goals except SDG14.


NK's founding business was the manufacture of leather bags, etc., and its business history has continued to operate in Adachi-ku, Tokyo, which is a hub of the leather industry. I have come to terms with it. The fact that it is just meat residue, the fact that we are an extension of a long history of over 1000 years, the people who have been involved, the local community, and the value that it continues to be used in many fashions including luxury brands.

On the other hand, the realities of business sites for animals, meat, and leather around the world, which we became aware of in the process of taking on the challenge of becoming a global international certification "B Corporation," which the entire company has been working on since 2021, are beyond our expectations. It was far superior. It is not uncommon for the supply chain to be a ranch far away from the fashion and food scene in Japan, far away from a ranch overseas. However, it is generally difficult to grasp even in Japan, and it is normal in business that the traceability is unclear overseas. How can we make a long-term commitment to the core themes of the SDGs, such as alteration of vast lands, deforestation of wetlands and forests, livestock feed, mass emissions of greenhouse gases, transportation and slaughter, and human rights? Whether or not we can handle the mix change, NK will put them into practice in our daily business operations as the core of our own management.

■ NK Procurement Selection Principles


・Be a certified supplier of LWG (Leather Working Group, an international certification)

・In the leather production process, the tanning process, which uses the most water and chemicals, must be able to demonstrate a reduction of 50% or more compared to conventional processing.

・It must be possible to demonstrate the practice of solid animal welfare in the growth process of the animal that receives the raw hide.

・Customers must understand and adopt the product design to minimize scraps generated in the production process of products using leather.

Production line "value created by an extremely low "defect rate""

The defect rate of NK is less than 0.01%. We are proud of this figure, which is achieved by combining the traditional techniques nurtured in the leather industry community of Tokyo, including neighboring Adachi Ward, with our unique quality control, equipment selection, and maintenance techniques. . And this pride is not only for us, but also for all companies that continue to earnestly engage in the manufacturing industry in Japan.

Many of the defective products become waste together with process scraps. In other words, making the defect rate as close to zero as possible is the “manufacturing responsibility” itself in the manufacturing industry.

NK often receives materials from customers and business partners. In such cases, it is common for first-time customers to pay "loss included" in consideration of the possibility of defects. However, due to NK's defect rate, on average 20% of the supplied material is returned to the supplier without being used in the end, so many customers can use it for future transactions with us or other transactions. This also leads to cost reduction for the customer.

The table below shows the weight value of waste that NK measures every month. We set the actual amount of waste in the previous term as a KPI for this term at the beginning of the term, and we are working to always fall below the results of the previous term (reduce the amount of waste). I'm here.


And more importantly, we believe that reducing the use of leather throughout our supply chain will lead to less procurement, less transportation, less greenhouse gas emissions, and ultimately biodiversity conservation. We are promoting daily factory operations as a long-term management index.

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Production line "further 'minimization of waste'"

In addition to minimizing the defect rate, the two pillars of waste minimization management that NK is working on are the "material selection process" and the "cutting process."

■ Material selection

In the case of consumer products such as bags, if the stains and scratches inherent in the material itself, such as animal leather, are avoided, scraps will be generated and waste will be generated accordingly. Ultimately, it will be essential to build an understanding among users (consumers, consumers), but we will not accept scratches on new products, In today's society, where there is a mixture of two mindsets: "It doesn't matter if there are scratches on the product in order to minimize the environmental impact", it is possible to minimize waste by including "materials that do not have scratches or stains in the first place" as an option. It is possible to realize

■ Cutting process


 For conventional material cutting, it is customary to use a "cutting die (mold)" for cutting leather, for example. For the cutting die, it is necessary to make a steel mold that matches the shape of the final product (various shapes such as bags and wallets). This mold is used to extract the material, but since it is difficult to extract every corner of the material, the amount of offcuts generated inevitably increases. On the other hand, the ultra-high-definition cutting equipment that NK uses is capable of delicately extracting every corner of the material, minimizing the amount of offcuts generated.


We have demonstrated that by combining "materials" and "cutting methods," we can reduce the amount of scrap waste generated by 93.8% compared to conventional cutting methods.

(See demonstration image)


Production line "differences in environmental load created by production equipment"

Japan's pride as a "manufacturing" and a "technical powerhouse" that Japan has long promoted to the world is no longer an era where the focus is only on manufacturing and its manufacturing quality. With that alone, it is not possible to realize an “ideal capitalism” that comprehensively examines the impact on all stakeholders, including the global environment and society as a whole.

NK is realized by thoroughly verifying and repeating practice how the "cutting blade", a part used in the cutting process, which is our core process, can reduce the environmental burden.

Leading cutting blade in the industry: Uses Swedish steel molds "Example: mold weight 2,171 gm (see image)"

Problem 1: Global environmental impact 1 Disposal of target products when production ends. (It can be melted and reused at high temperatures, but it consumes a lot of energy and emits greenhouse gases.)

Issue 2: Global Environmental Impact 2 Mining of the steel used to make the mold itself. And various energy such as electricity generated in the mold manufacturing process and greenhouse gas emissions

Problem 3: Business management burden A large number of molds are constantly used, so storage space and buildings are required in the bag manufacturing factory, which is a financial burden.

Cutting blade in NK: using microblading. "Blade weight 2 gm (see image)" Cutting machine powered by 100% renewable energy

Resolving Problem 1: The amount of steel used is only 0.09% compared to the conventional mold in the above example. Reducing greenhouse gas emissions at the time of disposal (in some cases, dissolving at high heat for reuse)

Resolving Problem 2: Since it is only 0.09% compared to conventional molds, it reduces energy consumption and greenhouse gas emissions in all processes such as blade production and transportation, as well as the amount of steel mined.

Resolving issue 3: Since a single machine and microblade can be used to handle all kinds of product molds, there is no need to manufacture molds to suit each product. No storage space required.

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