Patent · US Expired

Hydrolyzable diffusion control layers in photographic products

US4547451A · kind A · utility

4Cited by
5References
25Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 21, 1985
Grant dateOct 15, 1985
Priority date
Expiry dateFeb 21, 2005

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S430/156
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

Photographic diffusion transfer film units including polymeric diffusion control layers are disclosed. The diffusion control layers comprise polymers which are hydrolyzable in an alkaline medium so as to convert a layer comprising one or more of the polymers from a condition of impermeability to alkali or materials soluble in or solubilized by an aqueous alkaline processing composition to a condition of substantial permeability thereto.

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