Claims
- 1. A method for preparing a photosensitive element comprising a support and on one or both sides thereof at least one silver halide emulsion layer, comprising silver halide grains precipitated in the presence of an organic hole-trapping dopant represented by formula (I) or (II), wherein formula (I) corresponds to a structure as follows: R—COOM (I)whereinR represents hydrogen, an alkyl group, an aryl group, an aralkyl group or hetero-aryl group, and wherein M is hydrogen or any metal or organic group which can form a salt; and wherein formula (II) corresponds to a structure as follows: wherein:X and Y are independently selected from O, S, Se; m is 1 and n is 1 or 2; R1 and R2 each independently represents hydrogen, an alkyl group, an aryl or aralkyl group or a heteroaryl group, wherein R1 and R2 may be the same or different and may form a ring; E represents a group linked to the carbon atom by a heteroatom, having at least one free electron pair; M+ is a proton or an organic or inorganic counterion; and said organic hole-trapping dopant being introduced during precipitation of the silver halide grains via the silver salt inlet or via a separated third inlet system.
- 2. A method according to claim 1, wherein an oxidizing agent is present together with said organic hole-trapping dopant.
- 3. A method according to claim 2, wherein the oxidizing agent is p-toluene thiosulphonic acid or a salt thereof.
- 4. A method for preparing a photosensitive silver halide element according to claim 1, wherein the precipitation is performed in following conditions of pH and pAg:pH in the range from 1 up to 10, and pAg in the range from 2 up to 9.
- 5. The method according to claim 1, wherein the silver halide grains are precipitated so that compounds satisfying formula (I), formula (II), or a combination of formula I and formula II are introduced during precipitation of the silver halide grains via a separated third inlet, wherein the third inlet is mounted in such as way that the hole-trapping dopant is supplied underneath a surface of a solution wherein the silver halide is precipitated.
- 6. The method according to claim 5 wherein the silver halide grains are precipitated so that compounds satisfying formula (I), formula (II), or a combination of formula I and formula II are introduced during precipitation of the silver halide grains via the separated third inlet, wherein the third inlet is positioned closer to the silver salt inlet than to a halide inlet.
- 7. The method according to claim 2 where the oxidizing agent is present before the organic hole-trapping dopant is injected in the precipitation step of the silver halide emulsion crystals.
- 8. The method according to claim 1, wherein the silver halide grains are precipitated by simultaneous addition of the compounds satisfying formula (I), formula (II), or a combination of formula (I) and formula (II) and the silver salt solutions through one inlet.
- 9. The method according to claim 8, wherein said compounds satisfying formula (I), formula (II), or a combination of formula (I) and formula (II) and silver salt are mixed together before formation of the silver halide.
Priority Claims (1)
Number |
Date |
Country |
Kind |
97203897 |
Dec 1997 |
EP |
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Parent Case Info
This is a division of application Ser. No. 09/209,761 filed Dec. 11, 1998 which claims benefit of No. 60/073,789 filed Feb. 5, 1998.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
5763151 |
Brust et al. |
Jun 1998 |
A |
5965343 |
Nishimura |
Oct 1999 |
A |
Provisional Applications (1)
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Number |
Date |
Country |
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60/073789 |
Feb 1998 |
US |