Hi-Top is applied in various fields as an advanced tin plate material.
Since our founding in 1934, we have grown together with our customers by manufacturing tin plate and tin-free steel as a material for containers. The technology that we developed with our customers continues to evolve, and we are now focusing on new uses that can contribute to the solving of environmental problems.
Hi-Top is an advanced tin plate material that we were the first in the world to successfully commercialize. Hi-Top is tin-free steel, which means that tin is not used in the plating process, with an electrolytic chromic acid process used to form thin and uniform layer on the steel sheet. Hi-Top has excellent corrosion resistance and paintability, and is used in a wide range of applications including crown caps, white caps for bottling, and printing plate-making materials.
Reliable processability
Its paint adhesion is extremely strong, and processing is easy. It also blends well with paints, providing an attractive surface after coating and printing.
Strong heat resistance
Strong heat resistance means it can withstand high-temperature baking finishes (about 400°C). It is also resistant to alkaline and neutral pH, and can be used without coating in some cases.
Outstanding corrosion resistance
Although an extremely thin film, it offers excellent corrosion resistance. (Conforms to the Food Sanitation Act.)
Our Products
Hi-Top（HT）
This is a surface-treated steel sheet with electrolytic chromic acid treatment applied to the surface of cold-rolled steel sheet. Toyo Kohan was the first company in the world to commercialize this product (as Hi-Top) in 1961 as an alternative to expensive tin plating.
WHT2／D-WHT
Plating a small quantity of tin on the steel sheet’s surface enables high-quality welding without needing to grind the plated film before welding, and also prevents contamination of manufacturing equipment with polishing powders.
Compared to Hi-Top, it offers superior slip for processing tools, eliminating the need for processing lubricants.
D-WHT is treated with Hi-Top on one side.
Applications
- Crown caps
- Food cans
- Beverage cans
- Metal caps
- 18-liter cans
- Candy tins
- Spray cans
- Exterior of home appliances
- Electrical and electronic parts
Examples！
Crown Caps（Hi-Top）
Opening a bottle with a crown cap gives a unique kind of joy and pleasure, and Toyo Kohan is happy to add that touch of splendor to celebrations and special occasions.
Manufacturing process
Hi-Top, which is used for a wide range of applications including can materials, is manufactured under strict quality control to ensure the right characteristics for each application.
Properties
| Product | Hi-Top | ||||
|---|---|---|---|---|---|
| Hi-Top（TFS） | K-3 HT | WHT-1 | WHT-2 | ||
| Weldability | RC value (mΩ)1 | 100～200 | 30～70 | 0.1～0.3 | 0.1～0.3 |
| Evaluation | × | △ | ○ | ○ | |
| Rust resistance | Salt spray test2 | △ | × | △ | △ |
| Paint adhesion | Cup process adhesion test3 | ◎ | ◎ | ◎ | ◎ |
| T-peel test4 | ◎ | ◎ | ◎ | ◎ | |
- 1 RC value: After heat treatment at 205°C for 20 minutes, contact electrical resistance is measured with our RC measuring device (RC value: Low → Weldability: Good)
- 2 Salt spray test: Sprayed with 5% salt water at 35°C for 2 hours → Visual evaluation
- 3 Cup process adhesion test: Lacquer coating → Cup process → Forcibly peeling off paint film on cup walls with tape → Visual evaluation
- 4 T-peel test: Lacquer coating → Cut into 5 mm strips → Heat-compression bond two sample pieces via nylon film → Peeling off and measuring stress
Weldability
The following diagram shows an example of the weldable current range using manufactured can seam welder.
Good welding materials possess a wide weldable current range.
Available Sizes
The manufacturable range depends on the combination of each specification (thickness, width, temper etc.).
Ask us especially about combination specifications with sheet thickness upper and lower limits and sheet width upper limits.
Also ask us about specifications as needed.
Sheet
| Normal manufacturing range | Manufacturable range | |
|---|---|---|
| Sheet Thickness（mm） | 0.15 to 0.50 | 0.13 to 0.60 |
| Sheet Width（mm） | – | 670 to 1,060 |
| Length（mm） | 510 to 1,070 | 460 to 1,110 |
Coil
| Normal manufacturing range | Manufacturable range | |
|---|---|---|
| Sheet Thickness（mm） | 0.15 to 0.60 | 0.07 to 0.80 |
| Sheet Width（mm） | – | 670 to 1,060 |
Hoop
| Normal manufacturing range | Manufacturable range | |
|---|---|---|
| Sheet Thickness（mm） | 0.15 to 0.50 | 0.13 to 0.60 |
| Sheet Width（mm） | 30 to 500 | 10 to 500 |
Standards
Hi-Top is manufactured under strict quality controls, based on the standard defined in JISG 3315.
Temper grade
| Temper grade symbol | Hardness (HR30TSm) | Features | |||
|---|---|---|---|---|---|
| Thickness t (mm) | |||||
| t≦0.210 | 0.210<t≦0.280 | 0.280<ｔ | |||
| Single rolled | T-1 | 50±4 | 49±4 | 48±4 | Particularly excellent flexibility |
| T-2 | 54±4 | 53±4 | 52±4 | Moderate flexibility and toughness | |
| T-2.5 | 56±4 | 55±4 | 54±4 | Flexibility and moderate toughness | |
| T-3 | 58±4 | 57±4 | 56±4 | Moderate toughness | |
| T-4 | 62±4 | 61±4 | 60±4 | Relatively high toughness | |
| T-5 | 66±4 | 65±4 | 64±4 | Excellent buckling resistance | |
| Twice rolled | DR-8 | 72±4 | Excellent rigidity and strength | ||
| DR-9 | 75±4 | Excellent rigidity and strength | |||
| DR-9M | 76±4 | Excellent rigidity and strength | |||
| DR-10 | 79+3,−4 | Outstanding rigidity and strength | |||
Amount of plating (one side)
| Metallic chromium layer | Hydrated chromium oxide layer |
|---|---|
| At least 50, no more than 150 | At least 5, no more than 35 |
Surface finish
| Surface finishing name | Code | Surface roughness Target value µmRa | Features |
|---|---|---|---|
| Bright | B | 0.25 | Gloss finish for general purposes. |
| Light roughness side | BR | 0.30 | Lightly grinded finish only used for double rolled products. |
| Rough | R1 | 0.40 | An original whetstone-like finish on which scratches do not show up. |
| Matte | M | 1 | Dull finish without any orientation. |