DDPASS
Transparent thick layer passivation
A wide range of passivations meet the most diverse requirements. With the GC PASS passivation systems, silver, transparent, blue, yellow or black coloured coatings of zinc or zinc alloys can be obtained according to the desired finish or the required corrosion resistance.
DDPASS creates a blue to violet iridescent chromium (VI) and fluoride-free thick layer passivation on galvanised surfaces. It is therefore equally suitable for the post-treatment of zinc layers from acidic, alkaline cyanide-free, and alkaline-cyanide processes.
Can be used with barrel and rack systems, galvanised and passivated surfaces achieve high protection values even after heat treatment of 24 hours at 120 °C, for example. The passivation is insensitive to annealing temperatures up to 210 °C.
Long service lives are achieved by the relative insensitivity to iron.
Analysis of the passivation solution is easy.
DD PASS yellow
Yellow thick layer passivation
By adding DDPASS part 2, a rich yellow precipitate with consistently good properties is formed.
Visually, the yellow layer clearly differs from conventional thick film passivation coatings. Any mix-up during assembly and production is practically excluded.
The unique intense yellow colour provides a variety of applications in the lock, fitting and furniture industry.
DDPASS yellow iridescent
Yellow iridescent thick layer passivation
DDPASS yellow iridescent was developed as a chromium (VI)-free replacement for yellow chromate coating. One or two-components are used in combination with a sealant to create rich, brass-coloured precipitates with consistently good properties. The two-component system allows individual control in the yellowish or red colour spectrum.
DDPASS HT (HIGH TEMPERATURE)
Thick layer passivation with impressive performance at higher temperatures
DDPASS HT was developed for use at higher temperatures up to 220 °C. The special feature of this passivation is that even at these temperatures, no optical changes occur and consistent corrosion protection is achieved. DDPASS HT produces blue to violet iridescent surfaces.
Coating parameters
| Product | Coating in l/100 l | Ph range from-to | T in °C | t in s | Max. metal impurity content in g/L | Service life in m2/l |
| DDPASS | 10 -18 | 1.8 -2.1 | 25 -45 | 30 -70 | Zn: 15, Fe:0.15 | 2.5 |
| DDPASS HT | 8 -15 | 2.0 -2.4 | 20 -40 | 40 -70 | Zn: 15, Fe:0.15 | 2.5 |
| Yellow thick film passivation | ||||||
| DDPASS | 15 -21 | 1.6 -2.2 | 20 -50 | 30 -70 | Zn: 15, Fe: 0.15 | 2.5 |
| DDPASS part 2 | 0.7 -1 | |||||
| Yellow iridescent (two-part) thick film passivation | ||||||
| DDPASS | 15 -21 | 1.8 -2.1 | 20 -50 | 30 -70 | Zn: 15, Fe: 0.15 | 2.5 |
| DDPASS part 2 | 0.25 -1 | |||||
| DDPASS part 3 | 0.5 -1 | 25 -45 | ||||
| Yellow iridescent (one part) thick film passivation | ||||||
| DDPASS | 15 -21 | 1.8 -2.1 | 20 -50 | 30 -70 | Zn: 15, Fe: 0.15 | 2.5 |
| DDPASS part 4 | 0.5 -1.5 | 1.8 -2.1 | 25 -45 | 30 -70 | ||
| DDPASS ZeCo | 9 -11 | 2 -2.4 | 25 -35 | 45 -60 | Zn: 10, Fe: 0.1 | |
| DDPASS ZeCo HT | 9 -11 | 2 -2.4 | 25 -35 | 45 -60 | Zn: 10, Fe: 0.1 |
