US3005713A - Method of improving photographic silver halide emulsions - Google Patents
Method of improving photographic silver halide emulsions Download PDFInfo
- Publication number
- US3005713A US3005713A US48854A US4885460A US3005713A US 3005713 A US3005713 A US 3005713A US 48854 A US48854 A US 48854A US 4885460 A US4885460 A US 4885460A US 3005713 A US3005713 A US 3005713A
- Authority
- US
- United States
- Prior art keywords
- gelatin
- emulsion
- silver halide
- ahtl
- photographic silver
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 239000000839 emulsion Substances 0.000 title claims description 45
- 229910052709 silver Inorganic materials 0.000 title claims description 18
- 239000004332 silver Substances 0.000 title claims description 18
- -1 silver halide Chemical class 0.000 title claims description 15
- 238000000034 method Methods 0.000 title description 11
- 229920000159 gelatin Polymers 0.000 claims description 52
- 108010010803 Gelatin Proteins 0.000 claims description 51
- 235000019322 gelatine Nutrition 0.000 claims description 51
- 235000011852 gelatine desserts Nutrition 0.000 claims description 51
- 239000008273 gelatin Substances 0.000 claims description 50
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 17
- 230000003647 oxidation Effects 0.000 claims description 9
- 238000007254 oxidation reaction Methods 0.000 claims description 9
- BWGNESOTFCXPMA-UHFFFAOYSA-N Dihydrogen disulfide Chemical compound SS BWGNESOTFCXPMA-UHFFFAOYSA-N 0.000 claims description 7
- 239000000047 product Substances 0.000 claims description 7
- NRFJZTXWLKPZAV-UHFFFAOYSA-N N-(2-oxo-3-thiolanyl)acetamide Chemical compound CC(=O)NC1CCSC1=O NRFJZTXWLKPZAV-UHFFFAOYSA-N 0.000 claims description 5
- 239000007795 chemical reaction product Substances 0.000 claims description 5
- 229960004753 citiolone Drugs 0.000 claims description 5
- 239000000243 solution Substances 0.000 description 12
- 239000011248 coating agent Substances 0.000 description 8
- 238000000576 coating method Methods 0.000 description 8
- SQGYOTSLMSWVJD-UHFFFAOYSA-N silver(1+) nitrate Chemical compound [Ag+].[O-]N(=O)=O SQGYOTSLMSWVJD-UHFFFAOYSA-N 0.000 description 8
- UMGDCJDMYOKAJW-UHFFFAOYSA-N thiourea Chemical compound NC(N)=S UMGDCJDMYOKAJW-UHFFFAOYSA-N 0.000 description 8
- 230000029087 digestion Effects 0.000 description 7
- 150000001875 compounds Chemical class 0.000 description 6
- IOLCXVTUBQKXJR-UHFFFAOYSA-M potassium bromide Chemical compound [K+].[Br-] IOLCXVTUBQKXJR-UHFFFAOYSA-M 0.000 description 6
- NLKNQRATVPKPDG-UHFFFAOYSA-M potassium iodide Chemical compound [K+].[I-] NLKNQRATVPKPDG-UHFFFAOYSA-M 0.000 description 6
- 239000000126 substance Substances 0.000 description 5
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Natural products NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 4
- 230000005070 ripening Effects 0.000 description 4
- 229910001961 silver nitrate Inorganic materials 0.000 description 4
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 239000007864 aqueous solution Substances 0.000 description 3
- 239000000499 gel Substances 0.000 description 3
- 230000001235 sensitizing effect Effects 0.000 description 3
- 238000003860 storage Methods 0.000 description 3
- PAYRUJLWNCNPSJ-UHFFFAOYSA-N Aniline Chemical compound NC1=CC=CC=C1 PAYRUJLWNCNPSJ-UHFFFAOYSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- QIGBRXMKCJKVMJ-UHFFFAOYSA-N Hydroquinone Chemical compound OC1=CC=C(O)C=C1 QIGBRXMKCJKVMJ-UHFFFAOYSA-N 0.000 description 2
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 2
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 2
- 239000000654 additive Substances 0.000 description 2
- 230000000996 additive effect Effects 0.000 description 2
- ZOJBYZNEUISWFT-UHFFFAOYSA-N allyl isothiocyanate Chemical compound C=CCN=C=S ZOJBYZNEUISWFT-UHFFFAOYSA-N 0.000 description 2
- 239000003957 anion exchange resin Substances 0.000 description 2
- 238000000502 dialysis Methods 0.000 description 2
- 150000002019 disulfides Chemical class 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 230000001965 increasing effect Effects 0.000 description 2
- 150000002500 ions Chemical class 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 239000012460 protein solution Substances 0.000 description 2
- 235000018102 proteins Nutrition 0.000 description 2
- 108090000623 proteins and genes Proteins 0.000 description 2
- 102000004169 proteins and genes Human genes 0.000 description 2
- REYLLNRLWCBKCM-YFKPBYRVSA-N (2s)-2-acetamido-4-sulfanylbutanoic acid Chemical compound CC(=O)N[C@H](C(O)=O)CCS REYLLNRLWCBKCM-YFKPBYRVSA-N 0.000 description 1
- NWUYHJFMYQTDRP-UHFFFAOYSA-N 1,2-bis(ethenyl)benzene;1-ethenyl-2-ethylbenzene;styrene Chemical compound C=CC1=CC=CC=C1.CCC1=CC=CC=C1C=C.C=CC1=CC=CC=C1C=C NWUYHJFMYQTDRP-UHFFFAOYSA-N 0.000 description 1
- JKFYKCYQEWQPTM-UHFFFAOYSA-N 2-azaniumyl-2-(4-fluorophenyl)acetate Chemical compound OC(=O)C(N)C1=CC=C(F)C=C1 JKFYKCYQEWQPTM-UHFFFAOYSA-N 0.000 description 1
- OROGUZVNAFJPHA-UHFFFAOYSA-N 3-hydroxy-2,4-dimethyl-2H-thiophen-5-one Chemical compound CC1SC(=O)C(C)=C1O OROGUZVNAFJPHA-UHFFFAOYSA-N 0.000 description 1
- ZVNPWFOVUDMGRP-UHFFFAOYSA-N 4-methylaminophenol sulfate Chemical compound OS(O)(=O)=O.CNC1=CC=C(O)C=C1.CNC1=CC=C(O)C=C1 ZVNPWFOVUDMGRP-UHFFFAOYSA-N 0.000 description 1
- 101710134784 Agnoprotein Proteins 0.000 description 1
- 241000283690 Bos taurus Species 0.000 description 1
- 241000283153 Cetacea Species 0.000 description 1
- 241001465754 Metazoa Species 0.000 description 1
- 206010034960 Photophobia Diseases 0.000 description 1
- 239000004372 Polyvinyl alcohol Substances 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- 229910021612 Silver iodide Inorganic materials 0.000 description 1
- DWAQJAXMDSEUJJ-UHFFFAOYSA-M Sodium bisulfite Chemical compound [Na+].OS([O-])=O DWAQJAXMDSEUJJ-UHFFFAOYSA-M 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- 235000016720 allyl isothiocyanate Nutrition 0.000 description 1
- HTKFORQRBXIQHD-UHFFFAOYSA-N allylthiourea Chemical compound NC(=S)NCC=C HTKFORQRBXIQHD-UHFFFAOYSA-N 0.000 description 1
- 229960001748 allylthiourea Drugs 0.000 description 1
- 229940101006 anhydrous sodium sulfite Drugs 0.000 description 1
- YEESUBCSWGVPCE-UHFFFAOYSA-N azanylidyneoxidanium iron(2+) pentacyanide Chemical compound [Fe++].[C-]#N.[C-]#N.[C-]#N.[C-]#N.[C-]#N.N#[O+] YEESUBCSWGVPCE-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 210000000988 bone and bone Anatomy 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 244000309466 calf Species 0.000 description 1
- 229920003064 carboxyethyl cellulose Polymers 0.000 description 1
- 239000005018 casein Substances 0.000 description 1
- BECPQYXYKAMYBN-UHFFFAOYSA-N casein, tech. Chemical compound NCCCCC(C(O)=O)N=C(O)C(CC(O)=O)N=C(O)C(CCC(O)=N)N=C(O)C(CC(C)C)N=C(O)C(CCC(O)=O)N=C(O)C(CC(O)=O)N=C(O)C(CCC(O)=O)N=C(O)C(C(C)O)N=C(O)C(CCC(O)=N)N=C(O)C(CCC(O)=N)N=C(O)C(CCC(O)=N)N=C(O)C(CCC(O)=O)N=C(O)C(CCC(O)=O)N=C(O)C(COP(O)(O)=O)N=C(O)C(CCC(O)=N)N=C(O)C(N)CC1=CC=CC=C1 BECPQYXYKAMYBN-UHFFFAOYSA-N 0.000 description 1
- 235000021240 caseins Nutrition 0.000 description 1
- 239000003729 cation exchange resin Substances 0.000 description 1
- 229920002678 cellulose Polymers 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000000084 colloidal system Substances 0.000 description 1
- 239000012153 distilled water Substances 0.000 description 1
- 239000000975 dye Substances 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- YAGKRVSRTSUGEY-UHFFFAOYSA-N ferricyanide Chemical compound [Fe+3].N#[C-].N#[C-].N#[C-].N#[C-].N#[C-].N#[C-] YAGKRVSRTSUGEY-UHFFFAOYSA-N 0.000 description 1
- 239000007888 film coating Substances 0.000 description 1
- 238000009501 film coating Methods 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- ILVUABTVETXVMV-UHFFFAOYSA-N hydron;bromide;iodide Chemical compound Br.I ILVUABTVETXVMV-UHFFFAOYSA-N 0.000 description 1
- 238000010348 incorporation Methods 0.000 description 1
- 238000011534 incubation Methods 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 208000013469 light sensitivity Diseases 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229930014626 natural product Natural products 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 229960002460 nitroprusside Drugs 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 229920002451 polyvinyl alcohol Polymers 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 150000003378 silver Chemical class 0.000 description 1
- ADZWSOLPGZMUMY-UHFFFAOYSA-M silver bromide Chemical compound [Ag]Br ADZWSOLPGZMUMY-UHFFFAOYSA-M 0.000 description 1
- 229940045105 silver iodide Drugs 0.000 description 1
- 229910000029 sodium carbonate Inorganic materials 0.000 description 1
- 239000011780 sodium chloride Substances 0.000 description 1
- AKHNMLFCWUSKQB-UHFFFAOYSA-L sodium thiosulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=S AKHNMLFCWUSKQB-UHFFFAOYSA-L 0.000 description 1
- 235000019345 sodium thiosulphate Nutrition 0.000 description 1
- 125000000446 sulfanediyl group Chemical group *S* 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 210000002435 tendon Anatomy 0.000 description 1
- 238000006177 thiolation reaction Methods 0.000 description 1
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
- G03C1/04—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein with macromolecular additives; with layer-forming substances
- G03C1/047—Proteins, e.g. gelatine derivatives; Hydrolysis or extraction products of proteins
Definitions
- This invention relates to photographic silver halide emulsions and particularly to the incorporation of a reaction product of gelatin with N-acetylhomocysteine thiolactone (AHTL) in such emulsion for the purpose of increasing speed or contrast, or both, of such emulsion, while reducing the fog and preventing loss of speed.
- AHTL N-acetylhomocysteine thiolactone
- Photographic silver halide emulsions are usually prepared by mixing soluble silver salts, e.g., silver nitrate with soluble silver halides, e.g., potassium bromide, potassium iodide or sodium chloride in the presence of colloids such as gelatin, carboxyethyl cellulose, water soluble casein, polyvinyl alcohol or others.
- soluble silver salts e.g., silver nitrate
- soluble silver halides e.g., potassium bromide, potassium iodide or sodium chloride
- colloids such as gelatin, carboxyethyl cellulose, water soluble casein, polyvinyl alcohol or others.
- ripeners or sensitizers exert a ripening or sensitizing efiect, that is, a speed or contrast increasing effect on the silver halide emulsion.
- Gelatin being a natural product and derived from various sources such as hides, bones, tendons, sinews and from difierent animals such as calf, cow, steer, pig, whale and being manufactured by different processes, may containmore or less or none of these substances.
- the nature or chemical structure of these substances is not in all cases completely known, although some authors have postulated that they are sulfur containing compounds.
- the method used for incorporating the aforesaid derivatives of gelatin consists of dissolving the derivative in water and adding this solution to the emulsion at a stage where its efiectiveness is most beneficial. Normally this is at the point where gelatin is added to -a photographic emulsion.
- An alternative method is to incorporate the derivative in the gelatin or gel substitute employed in preparing the photographic emulsion.
- N acetylhomocysteine thiolactone (AHTL) derivative of a gelatin is carried out ac- Patented Oct. 24., 1261 2 cording to the method described by R. Benesch and R. E. Benesch in the National Academy of Sciences of the U.S. Proceeding $44 848-53 (September 1958).
- the reaction proceeds according .to the following The reaction is carried out by treating an aqueous solution containing the gelatin-( 3-5 aud AHTL (of. Table I below) with alternate increments of AgNO and NaOH to keep the pH at 7.5 until a total of 1 mol of silver per mol of AHTL has been added.
- the reaction is complete when all the AG-AHTL complex has dissolved. This takes about one hour.
- the clear yellow solution of the silver mercaptide of the thiolated protein is adjusted to pH 2.5 and enough thiourea is added to convert all of the silver into the soluble Ag(thiourea) complex.
- This complex ion is removed with any commercial cation exchange resin and the protein is washed off the resin with acidified l M thiourea solution.
- the effiuent protein solution is then brought to pH 7 and passed through an anion exchange resin (cf. U.S. Patent 2,591,573) in order to remove some N-acetylhomocysteine which is formed as a byproduct due to hydrolysis of AHTL.
- the protein solution is finally freed of thiourea and salts by dialysis under nitrogen and lyophilized by removing water by evaporation at extremely low temperature and high vacuum.
- this water soluble disulfide can also be used within the scope of my invention. It has thedesirable faculty of reducing the fog tendencies during prolonged ripening.
- the quantity of the thiolated gelatin or the water soluble disulfide derived therefrom by oxidation is relatively small compared to the quantity of the emulsion or the gelatin or gel substitute employed. Usually amounts of from about .05 to .5 gram of the additive is employed per kilo of emulsion or gelatin or gel substitute.
- Any photographic gelatin may be utilized for my purposes. It is found that by the involved reactions such gelatins are converted to products having the characteristics contemplated herein.
- the thiolated gelatin and the water soluble disulfide have another very desirable and entirely unexpected property, namely, they prevent speed recession in storage and during the time prior to coating when the emulsion is melted andheld in a liquid state; i
- the oven test consists of a six-day incubation of the photographic test material at 53% relative humidity at sion at this stage was adjusted to 6.8.. During the mixing 7 and digestion, the temperature was held at 71 C. The emulsion was then cubed, washed and submitted to a second ripening process for which purpose the emulsion was melted in 2.0,minutes and heated to 49 C. ;The digestion was carried out for two hours. At the beginning of the digestion, 6 cc. of a 1% aqueous solution of Grams Metol 1.5 Sodium sulfite, anhydrous Sodium bisulfit 1 Hydroquinone 3 Sodium carbonate, monohydrated 6 Potassium bromide .8
- EXAMPLE II' In this example, the AHTL treated gelatin was applied as a coating final and not as an additive during the digestion, that is, it was added prior to coating while the emul- 'sion was being kept in the liquid state.
- a gelatino-silver halide emulsion containing 2% silver iodide and 98% silver bromide was prepared in a conventional manner and brought up to its maximum light sensitivity. It was then readied for coating and finals were added such as sensitizing dyes and hardening agents. Quantities of AHTL treated gelatin, as indicated in Table II, were added to the emulsion in the form of a 1% aqueous solution. The emulsion samples contained about 0.6 mol of silver halide. The soprepared emulsion samples were coated on a suitable cellulose ester base and dried. Samples of these film coatings were then exposed in a Type IB Sensitometer and developed in a developer of the composition of that described in Example I.
- Emulsion held at40 0-30 prior to coating 100 40 D Emulsion held at 40 C. 4 hoursprlor to coating 70 26 .40 400 mg. Emulsion held 4 hours 75 24 .37 800 mg. Emulsion held 4 hours 26 39 1.6 g Emulsion held 4 hours '90 28 41 3.0 g. Emulsion held 4 hours 24 35
- These results show appreciably reduced speed loss during the holding of the emulsion at 40 C. in the melted state prior to coatingin the cases where the AH'PL treated gelatin was present in the emulsion.
Landscapes
- 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)
- Compositions Of Macromolecular Compounds (AREA)
- Paints Or Removers (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Priority Applications (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| BE605223D BE605223A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) | 1960-08-11 | ||
| US48854A US3005713A (en) | 1960-08-11 | 1960-08-11 | Method of improving photographic silver halide emulsions |
| GB19870/61A GB928116A (en) | 1960-08-11 | 1961-06-01 | Improvements in or relating to photographic silver halide emulsions |
| FR865532A FR1299145A (fr) | 1960-08-11 | 1961-06-20 | Procédé pour l'amélioration des émulsions photographiques d'halogénure d'argent |
| DEG32913A DE1138315B (de) | 1960-08-11 | 1961-08-10 | Verfahren zur Herstellung stabiler photographischer Halogensilber-emulsionen erhoehter Empfindlichkeit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US48854A US3005713A (en) | 1960-08-11 | 1960-08-11 | Method of improving photographic silver halide emulsions |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3005713A true US3005713A (en) | 1961-10-24 |
Family
ID=21956802
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US48854A Expired - Lifetime US3005713A (en) | 1960-08-11 | 1960-08-11 | Method of improving photographic silver halide emulsions |
Country Status (4)
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3171831A (en) * | 1961-02-14 | 1965-03-02 | Schwarz Biores Inc | Thiolation of proteins by reaction with homocysteine thiolactone in the presence of tertiary amine |
| US3933421A (en) * | 1971-12-09 | 1976-01-20 | I.W.S. Nominee Company Limited | Polymer treatment of fibrous and filamentary materials |
-
0
- BE BE605223D patent/BE605223A/xx unknown
-
1960
- 1960-08-11 US US48854A patent/US3005713A/en not_active Expired - Lifetime
-
1961
- 1961-06-01 GB GB19870/61A patent/GB928116A/en not_active Expired
- 1961-08-10 DE DEG32913A patent/DE1138315B/de active Pending
Non-Patent Citations (1)
| Title |
|---|
| None * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3171831A (en) * | 1961-02-14 | 1965-03-02 | Schwarz Biores Inc | Thiolation of proteins by reaction with homocysteine thiolactone in the presence of tertiary amine |
| US3933421A (en) * | 1971-12-09 | 1976-01-20 | I.W.S. Nominee Company Limited | Polymer treatment of fibrous and filamentary materials |
Also Published As
| Publication number | Publication date |
|---|---|
| DE1138315B (de) | 1962-10-18 |
| BE605223A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) | |
| GB928116A (en) | 1963-06-06 |
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