CN104536256A - Method for preparing tabular granular silver halide emulsion - Google Patents
Method for preparing tabular granular silver halide emulsion Download PDFInfo
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- CN104536256A CN104536256A CN201410820983.3A CN201410820983A CN104536256A CN 104536256 A CN104536256 A CN 104536256A CN 201410820983 A CN201410820983 A CN 201410820983A CN 104536256 A CN104536256 A CN 104536256A
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Abstract
The invention discloses a method for preparing tabular granular silver halide emulsion. According to the invention, Tabular (tabular) granular (referred to as T-granular) emulsion with a high shape ratio is prepared by a two-step nucleus formation method by use of double-column emulsion, the shape ratio of the emulsion granules is higher than 20, and on the premise of proper scumbling, the maximum density of a film is higher than 3.5 (the silver content on a single surface is about 5.0 g/m2) through certain chemical sensitization. With the adoption of method disclosed by the invention, the dosage of silver is saved on the premise of meeting the market demand. The shape of the crystal is more regular compared with that in the prior art, and the uniformity of the crystal is improved.
Description
Technical field
The present invention relates to photosensitive material and manufacture field, more particularly, relate to the preparation method of the T-particle silver emulsion being applied to Non-Destructive Testing (NDT) industrial film industry.
Background technology
Bulky grain silver bromide crystal body structure containing iodine is conducive to improving film speed.The superiority of the T-particle silver emulsion of high row state ratio is demonstrated first in the patent US4439520 of the Kofron of Kodak.Solberg applies for a patent US4433048, and he improves T-particle on the basis of forefathers, and point out at particle periphery higher than the light sensitivity containing iodine at granular center containing iodine, the concentration improving rapidly iodine is more clear than the particle improving iodine concentration gradually.But the thickness of the particle prepared by them is less than 0.3, and particle diameter is greater than 0.6, some forms are than reaching the ratio of 8:1. what is called form than the diameter and grain thickness that refer to particle.The form of particle is stronger than the covering power of higher particle, and that is form is than higher more favourable to photographic property.In succession get more and more about the patent of Tabular (flat) particle (being called for short T-particle) and the report of document.The people such as Roger in 1991 also apply for a patent US5061616 report different PAg value under silver bromide emulsion, show that the form ratio of particle reaches more than 30.Define the concept of T-grain emulsion in patent US4439520, it points out that the form ratio of T-particle in emulsion is greater than 2, and the emulsion that projected area accounts for more than 50% of the total area is just called T-grain emulsion.
T-particle silver bromide emulsion relative to plain particles silver bromide emulsion there are two kinds.The first, high row state ratio; The medium form ratio that second thickness is thin.So-called high form ratio refers to that form ratio is greater than 8:1, than particle, so-called thin medium form refers to that the average thickness of particle is less than 0.2 μm, and form is than being 5:1 ~ 8:1.Successively there is many patents about improving T-particle shape ratio in the development along with T-particle, such as US5470698, Rochester have prepared the ultra-thin T-grain emulsion that projected area is greater than 90%, thickness is less than 0.08 μm.Maskasky has applied for that the many sections of patents about high bromine T-grain emulsion comprise US5693459, US5691131, the iodine containing 5 ~ 10mol% is described in the patent US6329131 of the people such as the Morimura of FUJI company of US5620840 and US5604085. Japan, form ratio is 2 ~ 30, the silver halide particle that projected area is greater than 80%.
Although many to the pertinent literature report of T-particle, but be all more suitable for scientific research, be applied to real suitability for industrialized production and also have certain limitation, such as emulsifying temperature is higher, emulsification times silver halide that is partially long, emulsification is on the low side, on the low side for production capacity during suitability for industrialized production.Such as patent US5061616 emulsifying temperature is 75 DEG C, and emulsification times is 79 minutes, if carry out with the emulsification pot of 500 liters the silver halide crystal that emulsification once can only produce 130 moles.This patent is by having formulated a set of technique and formula being more conducive to suitability for industrialized production to the dynamics of Crystallization and thermodynamic study.Emulsifying temperature is reduced to 65 DEG C, and the forming process of crystal is reduced to two one-step formings by three one-step formings, and emulsification times foreshortens to 40 minutes, and once can produce silver halide 275 moles with the emulsification pot of 500 liters, therefore production capacity improves more than 4 times.
Summary of the invention
Technical matters to be solved by this invention overcomes the deficiencies in the prior art, provides a kind of preparation method of T-particle silver emulsion.
The preparation method of T-particle silver emulsion of the present invention, is achieved by following technical proposals,
First a certain amount of potassium bromide is dissolved in the gelatin solution of 0.2 ~ 6.0% (mass percent) concentration, wherein the mass ratio of potassium bromide and gelatin solution is: 1:80-100, regulate pH value to 5.6, then 65 DEG C are warming up to, the instantaneous liquor argenti nitratis ophthalmicus adding 5.1% (mass percent) under the stirring rate of 1000rpm, then join in emulsification pot in an accelerated manner in the potassium halide solution of the liquor argenti nitratis ophthalmicus and 31% (mass percent) of 40% (mass percent) is in 40min simultaneously, stirring rate brings up to 1500rpm simultaneously, guarantee that final speed is 100 times of initial velocity, wherein the volume ratio of the liquor argenti nitratis ophthalmicus of 5.1% and the liquor argenti nitratis ophthalmicus of 40% is: 1:12-16, the volume ratio of the liquor argenti nitratis ophthalmicus of 40% and the potassium halide solution of 31% is: 1:0.8-1.2, when emulsification 33min, (the emulsification start time refers to that liquor argenti nitratis ophthalmicus and potassium halide solution start to add the fashionable time simultaneously) is instantaneous adds mass percent 30% liquor kalii iodide, the scope of addition is 1.0 ~ 5.0 % by mole (with total amount of substances of silver halide for radix), stirs 10min before taking the dish out of the pot,
Then emulsion is cooled to less than 45 DEG C from 65 DEG C, add sinking agent beta-naphthalenesulfonic-acid formal sodium salt (4% aqueous solution, 30-80ml), add the pH value of a certain amount of acetic acid adjustment solution near the isoelectric point of gelatin, namely PH is transferred to about 3.8, is removed by unnecessary salinity while being precipitated by silver halide particle; And then dissolve by the sodium carbonate liquor silver halide particle precipitation come of avaling of 0.03 ~ 0.06%, then add a certain amount of acetic acid PH and be transferred to about 3.8 and carry out second time sedimentation, thoroughly remove the salinity in solution;
Precipitum obtained above is carried out chemical sensitization, add gelatin and make overall glue silver than being (glue silver is than the ratio referring to gelatin and silver) between 0.8-1.2, deionized water 100ml, sodium carbonate liquor (the aqueous solution 1.8-2.6ml of 5%), potassium bromide solution (the aqueous solution 3-7ml of 2%), EDTA (5% aqueous solution 2-4ml), hypo solution (0.1% aqueous solution 0.5-5ml), gold trichloride (0.017% aqueous solution 2-12ml), ammonium thiocyanate (0.2% aqueous solution 2-12ml).Added after 180 minutes, 5-methyl-7-hydroxyl-1,3,4-tri-nitrogen Yin Duo Li piperazine (being called for short 583) (2% aqueous solution 3-15ml), 6-nitrobenzene imipramine (0.1% ethanolic solution 0.1-2ml), two tetrazole (0.1% ethanolic solution 0.1-2ml), ((0.05%-0.5%) of complete soln obtains T-particle silver emulsion for surfactant (0.05%-0.5% of complete soln), antiseptic.
Surfactant comprises succinate sodium 2-ethylhexyl (being called for short 1292), isooctyl phenol polyethoxylate sulfonic acid diethanolamine salt (being called for short DPS), fluorochemical surfactant; Fluorochemical surfactant such as ethoxy base class non-ionic fluorocarbon surfactant (being called for short FSO), alpha-hydro-omega-hydroxypoly oxygen ethene and α-fluoro-ω-(2-hydroxyethyl) gather the etherate dioxane (being called for short FSO100) of (difluoro methylene) (1:1), perfluorooctanoic acid etc.Antiseptic comprises phenol, Sodium Benzoate, sodium lactate and potassium sorbate etc.
Compared with prior art, the invention has the beneficial effects as follows and saved the use amount of silver under the prerequisite meeting market demand.The shape of crystal is relative to more regular prior art, and the degree of uniformity of crystal improves.
Embodiment
Below in conjunction with specific embodiment, the present invention is described in further detail.Should be appreciated that specific embodiment described herein only in order to explain the present invention, and be not used in this present invention of restriction.
As follows to concrete analysis of the present invention:
1) formation of silver halide particle comprises the nucleation of crystal and two processes of growing up of crystal.In the manufacture process of photosensitive material, gelatin is absolutely necessary as the film forming agent in the protective agent of silver halide crystal and cuticula.The growth of concentration on crystal of gelatin has impact to a certain degree, generally in the forming process of crystal, (is called emulsion process or perhaps physical ripening process in industry), and the scope of gelatin concentration is 0.2 ~ 6.0%.
2) in emulsion process, PBr (negative logarithm of the concentration of the bromide ion in solution) value is also very important to the growth of crystal, and usable range is 1.3 ~ 1.8.
3) the formation tool of feed postition to particle of iodine has a great impact, and the feed postition of iodine is divided into two kinds, and one is evenly add, and what iodine was disperseed in particle is more even; Two is instantaneous adding, and makes the dispersion of iodine in particle more concentrated.Potassium iodide is instantaneous to add, and the scope of addition is 1.0 ~ 5.0mole%.
4) photographic property of the emulsion after physical ripening can't meet the needs of product, so also must carry out suitable sensitizing process.The present invention's is the method for chemical sensitization.What select is the chemical sensitization that the combination of sulphur, selenium and gold is carried out.
5) preserve the no longer rising of process Fog density in use and later stage in order to ensure product.The material that some suppress photographic fog to generate also will be added in emulsion.This kind of material becomes antifoggant or stabilizing agent.Conventional comprises thiazoles, imidazoles and nitrogen azole material.Such as benzothiazoles salt, nitro glyoxaline salt, benzotriazole salt.Antifoggant and stabilizing agent can add in any process of producing and use according to specific needs.Such as in the forward and backward of emulsification and emulsion process, in ripe front and back and maturation or before coating, or this kind of material can be added in developing process.What the present invention selected is that nitro glyoxaline and two tetrazole material use as stabilizing agent.Add 6-nitrobenzimidazole in emulsion process, after maturation terminates, add 4-tri-nitrogen Yin Duo Li piperazine (being called for short 583), two tetrazoles etc.
6) on sheet base, carry out sprawling in order to making emulsion can be good at the surfactant-based material needing to add necessity.Surfactant is divided into anionic surfactant, cationic surfactant, non-ionic surfactant and amphoteric surfactant.What the present invention selected is anionic surfactant and fluorine-containing non-ionic surfactant.
7) conditions of exposure that the present invention is used is: colour temperature 5500K, 1/20 second visible light exposure time.
8) at 20 DEG C, D19b developing liquid developing 5min, fixing 10min in F5 stop bath.Concrete aobvious fixing formula is as follows:
Table 1 D19b developer solution (1000ml)
The pH value of this developer solution is about 10.25
Table 2 F5 stop bath (1000ml)
The pH value of this stop bath is about 4.0
Embodiment 1
First 6.48g potassium bromide is dissolved in the gelatin solution of 550ml of 0.6% concentration, regulate pH value to 5.6, then 65 DEG C are warming up to, under the stirring rate of 1000rpm instantaneous add 5.1% liquor argenti nitratis ophthalmicus 25ml, then join in emulsification pot in an accelerated manner in the potassium bromide 335ml of the silver nitrate 376ml and 31% of 40% is in 40min simultaneously, guarantee that final speed is 100 times of initial velocity, stirring rate is transferred to 1500rpm, when emulsification 33min, instantaneous adding before liquor kalii iodide 10ml takes the dish out of the pot stirs 10min simultaneously.
Then emulsion is cooled to less than 45 DEG C, adds sinking agent beta-naphthalenesulfonic-acid formal sodium salt (F-16), add the pH value of a certain amount of acetic acid adjustment solution near the isoelectric point of gelatin, PH is transferred to about 3.8 by the present invention.While silver halide particle is precipitated, unnecessary salinity is removed.And then dissolve with the certain density sodium carbonate liquor pancake come that will avale, then add a certain amount of acetic acid and carry out second time sedimentation, object is removed further by salinity unnecessary in system.
Medicine cake obtained above is carried out chemical sensitization.Add gelatin and make overall glue silver than being (glue silver is than the ratio referring to gelatin and silver) between 0.8-1.2, deionized water 100ml, sodium carbonate liquor (the aqueous solution 1.8-2.6ml of 5%), potassium bromide solution (the aqueous solution 3-7ml of 2%), EDTA (5% aqueous solution 2-4ml), hypo solution (0.1% aqueous solution 0.5-5ml), gold trichloride (0.017% aqueous solution 2-12ml), ammonium thiocyanate (0.2% aqueous solution 2-12ml).Added after 180 minutes, 5-methyl-7-hydroxyl-1,3,4-tri-nitrogen Yin Duo Li piperazine (being called for short 583) (2% aqueous solution 3-15ml), 6-nitrobenzene imipramine (0.1% ethanolic solution 0.1-2ml), two tetrazole (0.1% ethanolic solution 0.1-2ml), surfactant (0.05%-0.5% of complete soln), antiseptic (material such as complete soln (0.05%-0.5%).
Embodiment 2
According to example 1, be dissolved in by potassium bromide: gelatin concentration changes 1.2% into, other conditions are constant.
Embodiment 3
Be dissolved in by potassium bromide according to example 1: gelatin concentration changes 2.4% into, other conditions are constant.
Embodiment 4
Be dissolved in by potassium bromide according to example 1: gelatin concentration changes 3.6% into, other conditions are constant.
Embodiment 5
Be dissolved in by potassium bromide according to example 1: gelatin concentration changes 4.8% into, other conditions are constant.
Embodiment 6
Be dissolved in by potassium bromide according to example 1: gelatin concentration changes 6.0% into, other conditions are constant.
5 results
The results are shown in Table 3 for six object lesson gained particles above, and after adopting the conditions of exposure of the present invention's introduction and aobvious fixing processing, the results are shown in Table 4 for gained photographic property.
Table 3 gelatin concentration is on the impact of particle shape
Data as can be seen from table 3, in emulsion process, the concentration of gelatin is very large on the impact of particle shape, along with the raising of gelatin concentration when the concentration of gelatin is in 0.6 ~ 2.4% scope, the form of the silver halide particle formed increases than gradually, but occur that when gelatin concentration is greater than 2.4% the form of the silver halide particle that flex point is formed there occurs change and namely becomes octahedra particle by flat particle, and reduced gradually along with the particle diameter of the increase particle of gelatin concentration.
Table 4 photographic property contrasts
Data as can be seen from table 4, under silver measures almost identical prerequisite, the particles benefit of flat pattern is in the raising of film maximal density, and octahedra particles benefit is in the raising of film contrast.
The present invention, by changing the concentration of gelatin in emulsion process, has shown that the shape impact of the concentration of gelatin in emulsion process on particle is very large.The oarse-grained particle diameter of increasing along with gelatin concentration increases gradually, but has occurred change when gelatin concentration is more than 2.4% time, and along with the particle diameter of the increase particle of gelatin concentration reduces gradually, and the shape of particle also becomes octahedra shape by flat.Flat particle is conducive to the raising of film maximal density, and octahedra particles benefit is in the raising of film contrast.High row state than particle can meet silver amount (one side) be less than the prerequisite of 5.5 under maximal density reach more than 3.5.
Claims (4)
1. a preparation method for flat particle silver emulsion, is characterized in that, carries out according to following step:
First a certain amount of potassium bromide is dissolved in the gelatin solution of mass percent 0.2 ~ 6.0% concentration, wherein the mass ratio of potassium bromide and gelatin solution is: 1:80 ~ 100, regulate pH value to 5.6, then 65 DEG C are warming up to, the instantaneous liquor argenti nitratis ophthalmicus adding mass percent 5.1% under the stirring rate of 1000rpm, then join in emulsification pot in an accelerated manner in the potassium halide solution of the liquor argenti nitratis ophthalmicus of mass percent 40% and mass percent 31% is in 40min simultaneously, stirring rate brings up to 1500rpm simultaneously, guarantee that final speed is 100 times of initial velocity, wherein the volume ratio of the liquor argenti nitratis ophthalmicus of mass percent 5.1% and the liquor argenti nitratis ophthalmicus of mass percent 40% is: 1:12 ~ 16, the volume ratio of the liquor argenti nitratis ophthalmicus of 40% and the potassium halide solution of 31% is: 1:0.8 ~ 1.2, the instantaneous liquor kalii iodide adding mass percent 30% when emulsification 33min, the scope of addition is 1.0 ~ 5.0 % by mole, with total amount of substance of silver halide for radix, stirs 10min before taking the dish out of the pot,
Then emulsion is cooled to less than 45 DEG C from 65 DEG C, add mass percent 4% aqueous solution of sinking agent beta-naphthalenesulfonic-acid formal sodium salt, add 30 ~ 80ml, add the pH value of a certain amount of acetic acid adjustment solution near the isoelectric point of gelatin, namely PH is transferred to 3.7 ~ 3.9, is removed by unnecessary salinity while being precipitated by silver halide particle; And then dissolve by the sodium carbonate liquor of mass percent 0.03 ~ 0.06% silver halide particle precipitation come of avaling, then add a certain amount of acetic acid PH is transferred to 3.7 ~ 3.9, carry out second time sedimentation, thoroughly remove the salinity in solution;
Precipitum obtained above is carried out chemical sensitization, adding gelatin makes overall glue silver than being between 0.8 ~ 1.2, wherein glue silver is than the mass ratio referring to gelatin and silver, deionized water 100ml, aqueous sodium carbonate 1.8 ~ the 2.6ml of 5%, kbr aqueous solution 3 ~ the 7ml of 2%, 5%EDTA aqueous solution 2 ~ 4ml, 0.1% sodium thiosulfate solution 0.5 ~ 5ml, 0.017% gold trichloride aqueous solution 2 ~ 12ml, 0.2% ammonium thiocyanate aqueous solution 2 ~ 12ml, 2%5-methyl-7-hydroxyl-1 is added after 180 minutes, 3, 4-tri-nitrogen Yin Duo Li piperazine aqueous solution 3 ~ 15ml, 0.1%6-nitrobenzene imipramine ethanolic solution 0.1 ~ 2ml, 0.1% couple of tetrazole ethanolic solution 0.1 ~ 2ml, add the surfactant of the mass percent 0.05% ~ 0.5% of complete soln, add the antiseptic of the mass percent 0.05% ~ 0.5% of complete soln, finally obtain T-particle silver emulsion.
2. the preparation method of flat particle silver emulsion according to claim 1, is characterized in that, described surfactant is succinate sodium 2-ethylhexyl, isooctyl phenol polyethoxylate sulfonic acid diethanolamine salt or fluorochemical surfactant.
3. the preparation method of flat particle silver emulsion according to claim 2, it is characterized in that, described fluorochemical surfactant is etherate dioxane or the perfluorooctanoic acid of poly-(difluoro methylene) (1:1) of ethoxy base class non-ionic fluorocarbon surfactant, alpha-hydro-omega-hydroxypoly oxygen ethene and α-fluoro-ω-(2-hydroxyethyl).
4. the preparation method of flat particle silver emulsion according to claim 2, is characterized in that, described antiseptic is phenol, Sodium Benzoate, sodium lactate or potassium sorbate.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4952489A (en) * | 1987-07-24 | 1990-08-28 | Minnesota Mining And Manufacturing Company | Photographic elements comprising light-sensitive silver bromo-iodide emulsions |
| CN1050619A (en) * | 1989-09-30 | 1991-04-10 | 北京大学 | High speed precoating sensitive plate and method for making thereof and purposes |
| CN1187635A (en) * | 1996-10-15 | 1998-07-15 | 富士写真菲林株式会社 | Silver halide photographic material |
| CN1310357A (en) * | 2000-02-23 | 2001-08-29 | 富士胶片株式会社 | Silver halide photographic emulsion and silver halide photographic sensitive material |
| CN102338981A (en) * | 2010-07-23 | 2012-02-01 | 中国科学院理化技术研究所 | Efficient sensitization method suitable for platy silver halide grain emulsion |
-
2014
- 2014-12-25 CN CN201410820983.3A patent/CN104536256B/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4952489A (en) * | 1987-07-24 | 1990-08-28 | Minnesota Mining And Manufacturing Company | Photographic elements comprising light-sensitive silver bromo-iodide emulsions |
| CN1050619A (en) * | 1989-09-30 | 1991-04-10 | 北京大学 | High speed precoating sensitive plate and method for making thereof and purposes |
| CN1187635A (en) * | 1996-10-15 | 1998-07-15 | 富士写真菲林株式会社 | Silver halide photographic material |
| CN1310357A (en) * | 2000-02-23 | 2001-08-29 | 富士胶片株式会社 | Silver halide photographic emulsion and silver halide photographic sensitive material |
| CN102338981A (en) * | 2010-07-23 | 2012-02-01 | 中国科学院理化技术研究所 | Efficient sensitization method suitable for platy silver halide grain emulsion |
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