Since 1981, MIRALLOY® has been a good alternative for nickelfree coatings in the clothing industry. Today, our customers all over the world profit from more than 30 years of...
Copper-tin-(zinc) electrolytes as nickel-free alternatives
Since 1981, MIRALLOY® has been a good alternative for nickelfree coatings in the clothing industry. Today, our customers all over the world profit from more than 30 years of experience and the continuous further development of the product series.
With MIRALLOY®, electrolytes are used to deposit copper-tin(-zinc) coatings in rack and barrel plating. The colour of the coatings is white – similar to silver.
Plated garment accessories, such as zips and metal buttons, offer a very high level of resistance to everyday wear.
A further plating layer with gold, rhodium, palladium or other precious metals, as well as tarnish protection if required, can be added problem-free by choosing a suitable process and with the right pre-treatment.
Electrolytes Characteristics
| Electrolyte type | Alkaline-cyanide |
| Metal content | 8.5 g/l Cu 34.0 g/l Sn 0.75 g/l Zn |
| pH value | > 13 |
| Operating temperature | 60°C |
| Current density range | 0.5 (0.3 - 1.0) A/dm² |
| Plating speed | Approx. 0.12 μm/ min at 0.5 A/dm² |
| Anode material | MMO (type PLATINODE® 167, ) |
Coating Characteristics
| Coating | Copper-tin-zinc |
| Alloy Composition | 55 wt. % Cu 30 wt. % Sn 15 wt. % Zn |
| Colour of deposit | White |
| Brightness | Bright |
| Hardness | 550 HV |
| Max. coating thickness | 5 μm |
| Density of the coating | 8.2 g/cm³ |
Advantages
- Copper-tin-(zinc) alloy coatings
- Bright white coatings (similar to silver)
- Diamagnetic
- Nickel-free (§27 of REACH, Ann. XVII, Reg. (EC) No 1907/2006, Standard 100 by OEKO-Tex®)
- Free from heavy metals like Cr, Pb, Co, Th etc.
- Resistant to tarnishing and corrosion
- Excellent layer thickness distribution
- Wide operating range
- Can be lacquered
- Can be combined with precious metals
- The coatings are RoHS compliant
- Tried and tested process by many zip manufacturers
Applications
- Zip parts
- Metal buttons
- Bra fasteners
- Buckles
- Haberdashery
