Patent · US Expired

Aqueous cleaner for removing solder pastes

US5821208A · kind A · utility

9Cited by
16References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 24, 1996
Grant dateOct 13, 1998
Priority date
Expiry dateSep 24, 2016

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05K2203/0793
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

Printing applicators such as metal stencils and screens used to apply solder paste to printed circuit boards are cleaned to remove accumulated solder paste therefrom by an aqueous alkaline salt cleaner. The aqueous cleaner of the present invention comprises alkaline salts such as alkali metal carbonates, a surfactant formulation which contains at least one nonionic surfactant, an alkali metal silicate corrosion inhibitor and stabilizers to maintain the components in aqueous solution. The cleaner of the present invention contains no VOCs and is an effective and safe replacement for alcohol solvents previously used to clean solder paste from screens and stencils.

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