Classifications

• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
  • G03C1/00—Photosensitive materials
  • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
  • G03C1/06—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein with non-macromolecular additives
  • G03C1/08—Sensitivity-increasing substances
  • G03C1/10—Organic substances

Definitions

• arable constituents ranging from higher molecu ar weight polypeptide combinations of amino acids to lower molecular weight polypeptide fragments, and may even contain carbohydrates, aldehydes and other organic acids which sensitometrically affect photographic emulsions.
• This invention relates to a improved gelatino silver halide emulsion wherein pyrrolidine, 2-pyrrolidine carboxylic acid, or 4-hydroxy-2-pyrrolidine carboxylic acid is added, in the amount of from 0.13 to 3.34 grams per mole of silver, to increase sensitivity to radiation without increasing fog.
• the invention comprises a conventionally made emulsion to which has been added a small amount of pyrrolidine, 2-pyrrolidine carboxylic acid (proline), or 4hydroxy-2-pyrrolidine carboxylic acid (hydroxyproline) to improve its sensitivity to radiation without increasing its fog level.
• the emulsion may be one of various gelatino-silver halide emulsions and may include those having lower gelatin binder content.
• the sensitizing agents of this invention should be added in amounts from 0.05 to 5.0 grams per 1.5 mole of silver.
• proline, or hydroxyproline is added to the emulsion after digestion and before coating, although it may be added any time after the emulsion is coagulated, washed, and redispersed.
• the preferred emulsion product of this invention contains from 0.20 to 0.40 gram per 1.5 mole of silver of the pyrrolidine, proline, or hydroxyproline and also contains a reduced amount of gelatin of about grams to 130 grams per 1.5 mole of silver. This will give a photographic element which has a lower binder content and can be processed faster after exposure without a substantial loss in photographic sensitivity.
• the preferred silver halide is silver bromoiodide.
• EXAMPLE 1 through an aluminum /'2 stepwedge and no screen, for one minute at 200 kilovolts potential and 4 milliamps current.
• the samples were exposed, processed, and read as in Example 2, except that the relative speeds were measured at a density of 1.5.
• the following table shows the sample compositions and the resulting relative speed, average gradient, and net fog levels.
• Stabilizers and coating aids such as saponin, were also added to the emulsion.
• the emulsion was then divided into two equal parts. To the first part was added 0.32 g./l.5 moles of Ag of 2- pyrrolidine carboxylic acid; to the second part nothing was added.
• the sample with the 2-pyrrolidine carboxylic acid added exhibited higher relative speed, 197, and no increase in net fog level, 0.16, when compared to the control sample with no 2-pyrrolidine carboxylic acid added (speed, 153; net fog, 0.16).
• EXAMPLE 3 each containing 1.5 moles of silver halide and 100 grams of gelatin. A dilferent amount of proline was added to each portion.
• EXAMPLE 4 Amount of emul1on w P p 1n lq F P that Sample Proline (g./1.5 Relative Average prior to digestlon the emulsion was d1v1ded into two moles of p d Gradwnt Net Fog parts, one part having proline added to it prior to digestion 0 l 100 ()0 a; and one part continuing through the digestion step with- 8-38 i8 out proline. After digestion, the emulsion containing no proline was divided into two parts, a control and a portion to which proline was added. Coated samples were exposed, processed and analyzed as in Example 2. The compositions and results are shown in the table below.
• Example 2 Amount of Praline (g./1.5 mole Ag) Sample Before Aft-er Relative Average N0. Digestion Digestion Speed Gradeint Net Fog EXAMPLE 5 An emulsion was prepared as in Example 2, except that just after digestion and prior to the addition of final adjuvants, the emulsion was divided into six parts and a diflFerent amount of proline was added to each part. The compostions and sensitornetric data are shown in the table below, the coated samples being exposed and processed as in Example 2.
• a gelatino silver bromochloride emulsion containing 80.0 mole percent of AgBr and 20.0 mole percent of silver chloride, was coagulated, washed, and redispersed by the method described in assignees patent to J. A. Moede, US. 2,772,165.
• the redispersed emulsion containing bulking gelatin and gold and sulfur sensitizers was digested at 136 F. for minutes. After digestion, stabilizers and coating aids, such as saponin were added, and H the resulting emulsion was divided into three portions,
• the speed of the control was assigned the value 100.
• a gelatino-silver halide photographic emulsion containing from about 0.05 to 5.0 grams per 1.5 mole of silver a sensitizer ofpyrrolidine, 2-pyrrolidine carboxylic acid or 4-hydroxy-2-pyrrolidine carboxylic acid.
• sensitizer is present in an amount of about 0.20 to 0.40 gram per 1.5 mole of silver.

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• Physics & Mathematics (AREA)
• Chemical & Material Sciences (AREA)
• Spectroscopy & Molecular Physics (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• General Physics & Mathematics (AREA)
• Pyrrole Compounds (AREA)
• Compositions Of Macromolecular Compounds (AREA)
• Silver Salt Photography Or Processing Solution Therefor (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=24565019

Family Applications (1)

Country Status (5)

Citations (2)

• 1967
  • 1967-05-19 US US639655A patent/US3514292A/en not_active Expired - Lifetime
• 1968
  • 1968-05-10 GB GB22437/68A patent/GB1192490A/en not_active Expired
  • 1968-05-14 DE DE1772425A patent/DE1772425C3/de not_active Expired
  • 1968-05-16 FR FR1563490D patent/FR1563490A/fr not_active Expired
  • 1968-05-17 BE BE715318D patent/BE715318A/xx unknown

Patent Citations (2)

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