Patent · US Expired

Self-accelerating and replenishing non-formaldehyde immersion coating method

US5543182A · kind A · utility

17Cited by
36References
75Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 16, 1995
Grant dateAug 6, 1996
Priority date
Expiry dateFeb 16, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05K2203/0392
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A process for applying a metal coating to a non-conductive substrate without an electroless coating is disclosed. The process includes the step of: a. contacting said substrate with an activator comprising a noble metal/Group IVA metal sol to obtain a treated substrate; b. contacting said treated substrate with a self accelerating and replenishing immersion metal composition comprising a solution of (i) a soluble metal salt whose metal is more noble than said Group IVA metal, (ii) a Group IA metal hydroxide, (iii) a complexing agent comprising an organic material having a cumulative formation constant log K of from about 0.73 to about 21.95 for an ion of the metal of said metal salt. The Group IVA metal is employed in a stoichiometric excess compared to the noble metal, the excess Group IVA metal being in its lowest oxidation state. Self accelerating and replenishing non-formaldehyde immersion metal compositions are also disclosed. The composition is used in a two step process to electrolytically coat a nonconductive substrate. In the first step the conductivity of the substrate is increased by applying the composition to it. In the second step, the substrate treated with the compo…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.