Claims
- 1. A method for electroless deposition of a metal layer from a metallization liquid on a flat side of an article to be metallized more in particular a master disc, characterized that the side to be metallized is hydrophilic, the article is positioned with the hydrophilic side directed upwardly, in an at least substantially horizontal position, the hydrophilic side is made catalytic for electroless deposition, the article is supported so as to be rotatable, a quantity of metallization liquid is deposited on the hydrophilic side of the article in a manner such that during deposition the metallization liquid deposited on the said hydrophilic side assumes the shape of a layer of substantially constant thickness bounded by the edges of said article while said article is slowly rotated at a speed so as to maintain said layer in a substantially stationary position until a metal layer of sufficient thickness is deposited and then the remaining metallization liquid is removed.
- 2. A method as claimed in claim 1, characterized in that the thickness of the layer of metallization liquid is chosen between 0.5 and 5 mm.
- 3. A method as claimed in claim 2, characterized in that the thickness of the layer of metallization liquid is chosen between 3 and 4 mm.
- 4. A method as claimed in claim 1, characterized in that before depositing the metallization liquid on the article, both the metallization liquid and the article are heated above room temperature.
- 5. A method as claimed in claim 4, characterized in that a quantity of metallization liquid which is just sufficient for metallizing a single article is heated.
- 6. A method as claimed in claim 4, characterized in that the article is heated to a higher temperature than the metallization liquid in order that the combination of article and metallization liquid after depositing the metallization liquid assumes a temperature which has an optimum value for the metallization process.
- 7. A method as claimed in claim 6, characterized in that the article is heated to 57.degree. C. and the metallization liquid is heated to a temperature of 51.degree. C.
- 8. A method as claimed in claim 4, characterized in that the method is carried out within a housing in which an air flow is maintained at a controlled temperature and a controlled speed and the temperature of the layer of metallization liquid at the end of the metallization step remains above the temperature at which the deposition of metal from the metallization liquid stops.
- 9. A method as claimed in claim 8, characterized in that water vapor is added to the air flow to reduce evaporation of metallization liquid.
- 10. A method as claimed in claim 1, characterized in that the metallization liquid is deposited on the article from one or more outflow apertures with simultaneous slow rotation of the article.
- 11. A method as claimed in claim 1, characterized in that during the deposition of the metal the article is rotated uniformly at a speed which is a fraction of 1 Hz and such that said layer is maintained in said substantially stationary position.
- 12. A method as claimed in claim 11, characterized in that the speed is approximately 1/40 Hz.
- 13. A method as claimed in claim 1, 10, 11 or 12, characterized in that after completing the metallization step, the remaining metallization liquid is removed from the surface of the article by increasing the speed of rotation sufficiently to fling away said remaining metallization liquid under the influence of centrifugal forces.
- 14. A method as claimed in any of the preceding claims, characterized in that, preceding the metallization step, the method comprises a number of other steps in which liquids are provided on and removed from the side of the article to be metallized in particular solutions of silane, tannin, salts of tin, silver, palladium, and there is an intermediate rinsing with demineralised water and that the article is supported in a horizontal position and rotated also during said other steps.
- 15. A method as claimed in claim 1, characterized in that the thickness of the deposited metal layer is mesured by optical means by means of a beam of radiation having a wavelength for which the metallisatin liquid is transparent.
Priority Claims (1)
Number |
Date |
Country |
Kind |
9000323 |
Feb 1990 |
NLX |
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Parent Case Info
This is a continuation of application Ser. No. 07/960,212, filed Oct. 13, 1992, now abandoned, which is a continuation of application Ser. No. 07/651,897, filed Feb. 6, 1991, now abandoned.
US Referenced Citations (15)
Foreign Referenced Citations (4)
Number |
Date |
Country |
738035 |
Feb 1970 |
BEX |
1058021 |
Feb 1967 |
GBX |
881080 |
Nov 1981 |
SUX |
9005795 |
May 1990 |
WOX |
Continuations (2)
|
Number |
Date |
Country |
Parent |
960212 |
Oct 1992 |
|
Parent |
651897 |
Feb 1991 |
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