Nickel is the world’s main contact allergen. In Europe, around 15 to 20 percent of women and around five percent of men are sensitive to nickel - in women under 30, this figure rises to...
No nickel allergies by copper-tin-(zinc) electrolytes
Nickel is the world’s main contact allergen. In Europe, around 15 to 20 percent of women and around five percent of men are sensitive to nickel - in women under 30, this figure rises to around 40 percent. Once someone has developed a sensitivity, constant or repeated contact with the allergen causes the skin or mucus membrane to react with inflammation (e.g. skin rash). The use of nickel is restricted by Annex XVII to Entry 27 of REACH. The definition of ‘prolonged skin contact’ (ECHA Q&A No 935) has resulted in many consumer objects that previously were not affected by the nickel limit now being covered by the 0.5µg/cm²/week maximum.
In contrast to nickel, MIRALLOY® platings do not cause any allergic reactions in accordance with current scientific knowledge, meaning they provide a great alternative. In combination with nickel-free substrate materials and other nickel-free processes, the MIRALLOY® process facilitates the manufacture of skin-friendly products. Its skin tolerance has even been proven in trials with sensitive test subjects. MIRALLOY® has been successfully used as a nickel-free coating on objects all around the world.
Electrolytes Characteristics
| Electrolyte type | Alkaline-cyanide |
| Metal content | 8.5 g/l Cu, 34.0 g/l Sn, 1 g/l Zn |
| pH value | >13 |
| Operating temperature | 60°C |
| Current density range | 2.0 A/dm² |
| Plating speed | Approximately 0.28 μm/min at 2.0 A/dm² |
| Anode material | MMO (type PLATINODE® 167, graphite) |
Coating Characteristics
| Coating | Copper-tin-zinc |
| Alloy Composition | 50 wt. % Cu 40 wt. % Sn 10 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 of white or yellow colour
Nickel-free (§27 of REACH, Ann. XVII, Reg. (EC) No 1907/2006, Standard 100 by OEKO-Tex®)
Free of heavy metals such as Cr, Pb, Co, Th, etc.
Can be combined with precious metals
Diamagnetic
Resistant to tarnishing and corrosion
Excellent layer thickness distribution
Can be lacquered
The coatings are RoHS compliant
Does not cause allergic reactions in the way that nickel does
Applications
Fashion jewellery
Clothing accessories
High-frequency technology
Craft tools
Writing tools
Glasses frames
Work tools
Buckles
Handles and steering wheels
Personal hygiene devices
Mouthpieces of all kinds
Kitchen appliances
Electronic devices
