Radiographic elements with improved covering power
US5292631A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 3, 1992 |
| Grant date | Mar 8, 1994 |
| Priority date | — |
| Expiry date | Jun 3, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S430/167
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Monocyclic and polycyclic azoles having the following formula enhance the covering power of a developed silver image formed from a radiographic element comprising a radiation sensitive tabular grain silver bromide, silver bromochloride or silver bromoiodide emulsion layer containing grains having a mean equivalent circular diameter of at least 0.3 .mu.m and a grain population wherein at least 50 percent of the total grain population projected area is accounted for by tabular grains having a tabularity of greater than 8, as determined by the relationship: ##EQU1## wherein T is tabularity; ECD is the mean effective circular diameter in .mu.m of the tabular grains; and t is the mean thickness in .mu.m of the tabular grains. The azoles have the formula: ##STR1## wherein Z is --N.dbd. or --C(R.sup.5).dbd. where R.sup.5 is hydrogen, --NH.sup.2, aliphatic of 1 to 8 carbon atoms or aromatic of 1 to 8 carbon atoms; PA1 R.sup.4 is hydrogen, aliphatic of 1 to 8 carbon atoms or aromatic of 1 to 8 carbon atoms; PA1 R.sup.4 and R.sup.5 together complete a 5 or 6 membered heterocyclic nucleus containing 1 to 3 ring nitrogen atoms; PA1 L is a divalent aliphatic linking group containing 1 to 8 carb…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.