Patent · US Expired

Process for the manufacture of a watch case with a visible highly invariable surface

US3998671A · kind A · utility

1Cited by
8References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 18, 1973
Grant dateDec 21, 1976
Priority date—
Expiry dateDec 18, 1993

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG04B37/22
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

This invention relates to a process for the manufacture of a workpiece with a visible highly invariable surface characterized by the manufacture of a casting by sintering a mixture of powdered metal of one of at least one of the metals of the groups 4A, 5A and 6A of the periodic system of elements and a binding agent derived from one of at least one of the metals of the groups 1B and 8 of the periodic system; forming the casting to bring it in the definitive shape, finishing the face to be made invariable and submitting the thus obtained workpiece to heat-treatment for hardening it.

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