Kudamatsu Plant

The Kudamatsu Plant is a major production base of Toyo Kohan.
We are located in Kudamatsu City, Yamaguchi Prefecture where nature is still abundant. In 1934, with the dream of “Making Japan self-sufficient in tinplate,” our engineers brought a burning spirit to this city and started production.

Kudamatsu Plant, Toyo Kohan Co., Ltd.

  • ISO 9001 and 14001 certified factory (surface-treated steel plate, cold rolled steel sheet, FINE CLAD (cladding material))

  • Address:1302-1 Higashitoyoi, Kudamatsu, Yamaguchi

  • Land area: 530,000 m²

  • Production capacity: 50,000 tons/month

  • Items manufactured:
    • Tinplate (Electro-tinned steel sheet)
    • Hi-Top (Tin-free steel)
    • Hi-Pet (Laminated steel sheet)
    • Silver Top (Electro-galvanized steel sheet)
    • Ni-Top (Nickel-plated steel sheet)
    • VINYTOP (Vinyl chloride resin decorative steel sheet)
    • TOP (Cold rolled steel sheet)
    • MD (Magnetic disk aluminum substrates)
    • Fine Cast Film (Functional film for container and optics)
    • FINE CLAD (Cladding materials)
    • KH (Abrasion and corrosion-resistant hard alloy)

The Kudamatsu Plant, challenging “All Possibilities”

We can stably supply high quality products to meet any customer's needs. This is possible because we have all the facilities necessary to conduct R&D, production, shipment and even environmental preservation. These facilities include a technical research laboratory, production lines, harbor facilities to directly handle the delivery of raw materials and supplies and ship products, an environmental management center, etc.

1. Picking 2. Cold Rolling 3. Cleaning and Annealing 4. Temper Rolling and Double Cold Reduction 5. Surface Treatment Abrasion and Corrosion-Resistant Hard Alloys (KH) FINE CLAD Magnetic Disk Aluminum Substrates (MD) Fine Cast Film

Surface treated steel and plates line

1. Pickling

Continuous pickling line

This process is used to remove scales (oxidized iron) from the surface of hot coils.

2. Cold Rolling

Five-stand tandem cold rolling mill

Hot coil (thickness 1.6 to 3.5 mm) is rolled to a thickness of 0.15 mm to 1.6 mm according to the use.

3. Cleaning and Annealing

Rolling oil that has become attached to the coil surface is washed off.
Then, it is softly annealed in the furnace.

Continuous annealing line


Interior of a batch annealing furnace

4. Temper Rolling and Double Cold Reduction

Double cold reduction mill

Coils are lightly rolled to prepare the surface shape, then they are given an appropriate roughness and hardness.

5. Surface Treatment

Surface treatment such as tin electroplating, electrolytic chromate processing and resin lamination are applied, and various products are made according to the uses. This is a process in which Toyo Kohan's originality stands out.

Electrolytic Tinning Line

Tin plating is electrically applied to make tinplate.

Silver Top Line

A processing fluid with a zinc base and also containing cobalt and molybdenum is used for a combined electro-galvanizing process.

Ni-Top Line

Nickel electroplating is conducted in this line. Non lustrous, semi lustrous and lustrous finishes can be applied to the plating by changing the plating fluid.

Ni-Top line

Hi-Top Line

A special electrolytic process is used to make a strong coating of chromium metal and chromium hydroxides.

Hi-Top line

Lamination Line

Polyester film that has excellent heat resistance, barrier forming properties and that is easy to fabricate is continuously attached with thermal compression bonding.

Lamination Line

Color Lamination Line

An organic film that allows high-class designs and functionality is applied.

Color Lamination Line

Functional Materials & New Materials manufacturing line



This is an highly functional laminated material made with the surface activated bonding process under a highly vacuumed environment. Because a flat joint surface can be produced, the states of the materials, such as thickness and hardness, are usable as is, so that this material can be used in many fields, such as material for battery components, material for printed circuit boards, etc.

Fine Cast Film

Fine Cast Film line

Polyester film that is made with the non-oriented film manufacturing method can be fabricated in ways that general purpose film cannot, and it forms a excellent bond with metals, so that it is used as the lamination film for making Hi-Pet, VINYTOP.

Magnetic Disk Aluminum Substrates (MD)

MD line

These are Magnetic Disk Aluminum Substrates made of aluminum disks, electroplated with nickel and then polished to a mirror finish. Although we have over 10 percent of the global market share, the uses of these disks has increased recently, so that in addition to computers they are now used in hard disk drive video recorders, car navigation systems, etc.

Abrasion and Corrosion-Resistant Hard Alloys (KH)

KH line

We are also providing our users with abrasion resistant, corrosion resistant and highly accurate long life machine components that are made with our hard materials, centering on our original KH alloy and including KW super-hard alloy and KA alumina-ceramics.