Patent · US Expired

Lithographic developer replenishment process

US4025344A · kind A · utility

13Cited by
5References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 23, 1975
Grant dateMay 24, 1977
Priority date
Expiry dateMay 23, 1995

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03C5/31
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

Lithographic developer in an automatic photographic film processor is replenished from at least two stable solution concentrates. As each quantity of lithographic film is processed predetermined amounts of the solution concentrates and water are mixed and immediately added to the developer. The solution concentrates, stable before mixing, contain all the constituents needed to replenish the developer solution to maintain activity at a desired level. The amount of each solution concentrate is predetermined from the concentration of each solution concentrate and the quantity and developer requirements of the film. The frequency of replenishment is predetermined from the usage pattern.

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