JPS5837635A - Manufacture of negative type photographic silver halide emulsion - Google Patents

Abstract

PURPOSE:To obtain a negative type photographic silver halide emulsion with high surface sensitivity and low internal sensitivity by a double jet method by keeping an excess concn. of water soluble silver salt and an acidic pH until the amount of added silver reaches a specified percentage of the total amount of silver to be added. CONSTITUTION:An emulsion is prepared while keeping 10<-5>-10<-2>mol/l concn. of silver ion (5-2pAg) and 1-4pH and increasing the adding speed of water soluble silver salt and that of water soluble halide continuously or in steps in accordance with the growth of silver halide particles until the amount of added silver reaches at least 1/15 of the total amount of silver to be added. Thus, a single-dispersion emulsion in which >=80wt% of the silver halide particles have a diameter within + or -40% of the average diameter is obtd. By sensitizing the emulsion by reduction or with sulfur or gold, a negative type photographic silver halide emulsion having a narrow particle size distribution and a uniform crystal habit is stably obtd. in a short time.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a negative-working silver halide photographic emulsion with high sensitivity and excellent production stability. This invention relates to a negative-working silver halide photographic emulsion containing silver oxide grains.

In recent years, silver halide photographic materials with high sensitivity have been desired. For example, regarding machinia film, color and black-and-white photographic paper, which requires high-speed shutters and rapid processing to eliminate shirt prints caused by the miniaturization of screens, and electronics in the printing process. Photosensitive materials are used as printing materials, which require high sensitivity due to simplification and simplification, and photosensitive materials for medical X-ray photography, which are strongly required to reduce the exposure radiation dose.

-P Recently, due to the rapid rise in silver prices, there has been a call for lower silver quantities, and high sensitivity technology is essential for this purpose.

Sensitivity enhancement technology has been studied in various ways. However, there is still room for research. 1+11 silver halide grains form a surface latent image and/or an internal latent image upon exposure. The surface latent image is developed with a conventional developer to give optical density, but the internal latent image is not developed. For this reason, in negative-working silver halide emulsions, halogen (E) grains, which tend to form internal latent images, have a greater sensitivity loss than white latent-image type silver halide grains, resulting in lower sensitivity. and conventional silver halide grains,
When unsensitized, the internal sensitivity was usually higher than the surface sensitivity. Therefore, it is desired to find a method for preparing negative-working silver halide emulsions with high surface sensitivity and low internal sensitivity.

It is the most suitable chemical sensitization for any particle during chemical sensitization due to the conventional halogen (?), silver emulsion poly(V, f), wide particle size distribution and uneven crystal habit. Therefore, the sensitivity inherent in each particle is not fully exploited at present.

Therefore, in recent years, monodisperse emulsions (i.e., narrow particle size distribution,
halogen silver emulsions with uniform crystal habits) are attracting attention. Although its preparation method is already known in various literature,
Most of Tonoshi et al.'s preparation methods were in the region of excess hala 1 do/1 ion.

On the side where there is an excess of halogen ions, the region in which a monodisperse emulsion can be obtained is narrow, around equimolar, and is limited to an unstable region in terms of flilJ control. In other words, by a slight increase in the excess halide concentration, the crystal habit changes from cubic to tetradecahedral, to octahedral in the furnace, and to a twinned polydisperse emulsion. Many documents have clarified that the 1'-C characteristics differ greatly between the crystal habits of Kone, et al. Therefore, in the preparation of a monodispersed emulsion with an excess of 1 ion halide, laboratory 1c is i':IJ ability and °C
However, it is unsuitable for continued industrially stable production. Therefore, it is strongly desired to find a method for industrially stably preparing monodispersed emulsions.

A first object of the present invention is to provide a method for producing a negative-working silver halide photographic emulsion that has high surface sensitivity and low internal sensitivity.

A second object of the present invention is to provide a method for producing a negative-working silver halide photographic emulsion having a narrow grain size distribution and uniform crystal habit.

A third object of the present invention is to provide a method for producing a negative-working silver halide photographic emulsion industrially and stably, which achieves the above two objects.

A fourth object of the present invention is to provide a method that can achieve the above objects in a short preparation time.

Other objects of the invention will become apparent from the description below.

The above-mentioned object of the present invention is to produce a negative-working silver halide photographic emulsion using the double-jet method. ! In the dipping method, pAg is
This is achieved by a method for producing a negative-working silver halide photographic emulsion in which the pH value is maintained at a value of 2 to 5 and a pH value of 1 to 4.

The present invention is characterized in that a silver halide monodisperse emulsion is prepared in a silver-excessive region. Its silver ion concentration is about 10
~10 mol/l (corresponding to pAg 5-2) is preferred, which is a concentration 10 to 1 million times higher than conventional. If the III degree is too low, there is a problem in the stability of production, while if it is too high, capliques will form inside the silver halide grains and the surface sensitivity will decrease. Overall, about pAg 4.5 to pAg 2.
5 is more preferred.

The silver ion concentration should be kept high until at least one-fifteenth of the amount of gold and silver is added. If this value is too small than the above, twins are likely to occur, resulting in a wide particle size distribution, making it difficult to stably obtain a monodispersed emulsion.

After addition of 1/15 of 1" of gold and silver, the silver ion concentration may be lowered to 10 mol/l or less. Furthermore, it is desirable that the concentration be 10 mol/l or more at the end of addition.

It is generally known that silver halide grains can be formed in any of basic, neutral and acidic conditions. The method according to the invention is carried out in an acidic region at least while maintaining a high silver 1 ion concentration. As the pH increases, internal sensitivity and internal fog increase, and surface sensitivity decreases. A low pfl value is effective, but there are problems such as a decrease in protective colloid properties due to hydrolysis of the protective colloid, etc., or corrosion of the mixed tank due to acid, so a pH of about 11 is practical.

This pH value may be set during the period during which the silver ion concentration is maintained high during the process of silver halide grain formation, and even if the silver ion concentration is increased to about i; l: pH 8. Although it does not affect the effect of the present invention, it is preferable that the pH does not exceed 7.5 in terms of keeping internal sensitivity and internal capri low. There are no particular restrictions on the acid used to obtain a low pH, but nitric acid, sulfuric acid, acetic acid, etc. are preferred.

In the present invention, after the nucleation period of the halogenated fjM grains is completed, as the length of Fli of the silver halide grains increases, the addition rate of water-soluble silver salt and water-soluble silver salt can be added to make the Fj more uniform. A monodispersed emulsion is obtained, and the opening 11 during mixing is shortened. Therefore, it is advantageous for industrial production and is preferable in that the chances of formation of structural defects inside the silver halide grains are reduced.

As a method of increasing this addition rate,
No. 890, No. 52-16364, JP-A-55-1.4
As described in No. 81 of each publication of No. 2329, the addition rate of the silver salt aqueous solution and the halide aqueous solution may be increased sequentially or stepwise. The upper limit of the above addition rate may be the flow rate just before new core particles are generated, and the value is determined by the flow rate, degree of pH-PAgs stirring, halogen (arsenal particle composition, solubility, particle size, @degree, crystal habit). , or it changes depending on the type and concentration of the protective colloid.

The silver halides used in Kinoi IJfl include silver bromide,
Silver iodobromide, silver chlorobromide, silver chlorobromoiodide, silver chloride, and silver chloroiodide are included, but the most preferred silver halide composition is silver iodobromide in which silver iodide is 10 molar or less. be.

The silver halide grains used in the present invention preferably have an average grain size of about 0.05 to about 2 microns. f
It is also desirable that at least 80% by weight of the silver halide grains have a diameter within ±40% of the average grain diameter. Further, these silver halide grains or silver halide emulsions may contain an iridium salt and/or a rhodium salt in order to improve flash exposure characteristics.

The negative silver halogenide photographic emulsion produced by the method of the present invention is chemically sensitized after the water-soluble salt M is removed by a conventional method. Chemical sensitization methods include, for example, sulfur sensitization method using sodium video sulfate, thiourea compounds, etc., gold sensitization method using chloroauric acid salts, gold trichloride, etc., thio dioxide base plate,
There are reduction sensitization methods using magnetization of stannous, silver ripening, etc., palladium sensitization methods, selenium sensitization methods, etc., and these methods can be used alone or in combination of two or more.

By the method of the present invention, IMij11! A stabilizer can be added to the negative-working silver halide emulsion after chemical sensitization. For example, 4-hydroxy-6-methyl-1,3
, 3a, 7-chitrazandene, 5-mercapl--1
Any stabilizer known in the art, including -phenyltetrazole, 2-mercaptobenzothiazole, etc., can be used. In addition, if necessary, it can be optically sensitized to a desired wavelength range by using optical sensitization using cyanine color chips, merocyanine dyes, etc. alone or in combination.

For example, U.S. Patent Nos. 2,493,784 and 2,51
No. 9.001, No. 2,977,229, No. 3 and 4
No. 80.343, No. 3,672,897, No. 3,
703.377-@, No. 2,688,545, No. 2,912.329, No. 3,397,060, No. 3,511.664, No. 3,522,052 ,
Same No. 3,527.641, Same No. 3,615.613, Same No. 3,615.632, Same No. 3,615,635
No. 3,615.641, No. 3.617.29
No. 5, No. 3.617.293, No. 3,628.9
64, No. 3,635.721, No. 3,656,
No. 959, No. 3,694.217, No. 3,743
, No. 510, No. 3,769.301, No. 3,79
The color charts described in No. 3,020 etc. can be used.

The negative-working silver halide photographic emulsion produced by the method of the present invention can contain gelatin, a gelatin derivative, or a synthetic hydrophilic polymer as a vehicle, and can also contain various photographic additives.
can be included.

As the hardening agent, aldehyde compounds, ketone compounds, halogen-substituted acids such as mucochloric acid, ethylene amine compounds, vinyl sulfone compounds, etc. can be used. Zabonin, lauryl or oleyl monoether of polyethylene glycol, etc. are used for spreading.

There are no particular limitations on the development accelerator, but compounds such as benzimidazole compounds (for example, /le, described in JP-A No. 49-24427), quaternary ammonium compounds, and polyethylene glycol can be used once a month.

As a physical property improver, a polymer latex made of a homo- or copolymer of alkyl acrylate, alkyl methacrylate, acrylic acid, etc. can be contained.

The negative-working silver halide photographic emulsion according to the method of the present invention is prepared by adding and copolymerizing dalicidol and enalene oxide to a phenol aldehyde condensate. compounds (for example, JP-A No. 51-56220)
:' listed), lanolin-based enalen oxide adducts and alkali metal clusters and/! f, bamboo alkaline earth gold salt (e.g., Japanese Patent Application No. 145022/1982), water-soluble inorganic chloride and matting agent (Japanese Patent Application No. 69242/1982), phenol aldehyde condensed fN, of course, dalicitol and ether. Addition condensate of ren oxide @ '3 ・kj and fluorine-containing fluorine-containing sulfuric acid compound (1.
940) etc. can be added.

Furthermore, it is possible to add 1 liter adjustment agent, thickening agent, graininess improver, matting agent, etc.

Examples of the support for Jl and J4 produced using the emulsion of the present invention prepared as described above include baryta paper, polyethylene paper, polypropylene paper, cellulose acetate, and cellulose acetate. , cellulose nitrate, polyvinyl acetal, polypropylene, polyester films such as polyethylene terephthalate,
Examples include polystyrene, and these supports are appropriately selected depending on the use of each silver halide photographic light-sensitive material. Further, it is desirable that these supports undergo surface hydrophilic treatment and tow treatment.

When applying the photographic emulsion according to the method of the present invention to a silver color photographic light-sensitive material, in addition to the various additives mentioned above, various constituent elements of the R1 light-sensitive material well known to those skilled in the art may be used. : Even if I do it, I won't have any disadvantages. For example, a compound that reacts with an acid-depleted developing agent to form a dye, i.e., r'
Ji! There are t%I diffusion-resistant couplers. More specifically, diketomenanes are represented by yellow couplers, 5-
There are magenta couplers typified by pyrazolone threads, phenolic threads, and cyan couplers typified by naphthol-based couplers.In addition to these couplers, there are so-called DIR force slurs that release development inhibitors during color reaction, and masking density. An example of this is a so-called colored coupler. These couplers are Re5earch D
isclosure (R,D, ) 9232.

Types of silver halide photographic light-sensitive materials to which photographic emulsions produced by the unexploded single-strength method can be applied include color photographic paper, color negative film, color positive film, black-and-white film (for example, X-ray light-sensitive materials, light-sensitive materials for printing, etc.), and diffusion film. Any type of photosensitive material such as a transfer force type photosensitive material may be used.

Exposure of photographic emulsions using the unexploded JJJ method varies depending on the type of optical sensitization, purpose of use, etc.
Various light sources can be used as appropriate, such as fluorescent lamps, mercury lamps, arc lamps, xenon, sunlight, xenon flashes, cathode ray tube flying spots, laser lights, electron beams, X-rays, and fluorescent screens for X-ray photography. , exposure time is 1/10
In addition to normal exposure of ~100 seconds, xenon flash,
For cathode ray tubes and laser beams, short-time or flash light of 1/10 to 1/10 seconds can be applied.

Next, I will explain it in detail using an example of an unexploded case.
The actual gun mode of the unfired ψJ is not limited to this.

Practical IAII Example - J PAg k T nd While directly controlling f in Table 1, using the double jet method (I: I) at 0.60° C. Eight loincloths (Δ~[I) were prepared from silver iodobromide milk shavings containing 0 mol%.

Dual engine power 11 speed 1 pursuit Jt, ? i A solution containing 2.0 mol/l of silver oxide and 2.0 mol/l of a mixed solution of potassium bromide and potassium iodide were mixed at an initial Vi of 1.0 m/l.
/min and (7, gradually increasing to 50d at the end)
/ minute. To obtain the desired IIAg candy, the addition rate of the potassium chloride and potassium iodide mixture was varied slightly from that of the silver nitrate solution. The pH value was adjusted with individual acid and potassium hydroxide. Addition of soda fr, 11.s
' fllll t/, J, 'It was 80 minutes. However, if the addition rate was not increased, approximately 20 hours of addition was required.

After mixing, the pAg was adjusted to 10% with potassium bromide water #i.
The total pH was adjusted to 6.5 with an aqueous solution of potassium hydroxide, and the water-soluble 17j was removed by a conventional #porous treatment at 40°C.

After gold sensitization and sulfur sensitization were applied to each of the eight emulsions of
, 3,3a-7-chitrazaindene was added to stabilize,
Before spreading, after adding general photographic additives such as thickeners and hardening agents, Ag fi is 50 / 100 on a subbed polyethylene terephthalate film base.
Samples NQ1~
8 was produced.

Sensitometry of each sample was carried out as follows. Exposure was carried out using a light source with a color temperature of 5400'K for 1000 seconds through an optical wedge.

Kirimitsu Tsuri 3.2 C, M, S. For development, surface development and internal development were carried out using a writing knife.

[Surface developer]

Incubate at 20°C for 10 minutes.

surface latent image bleaching solution] Process at 20°C for 10 minutes.

[Internal developer]

Sodium thiosulfate 5F (20 total 1
Add 0g.

After processing with the surface latent image bleaching solution, the entire surface is washed with running water for 1 minute, and internal development is carried out at 20° C. for 10 minutes.

Various properties of the obtained emulsion grains are shown in Table 2, L and development results are shown in Spectrum 3. Note that the sensitivity was expressed as a relative sensitivity with the surface sensitivity of the test needle level 2 being 100.

In the table, S represents sensitivity, Fog represents Cub IJ dl1 degree, and r represents contrast.

Hereinafter, "Margin Table-1 As is clear from Table-2 and Table-3, high silver ion concentration,
Silver halide grains formed under a 4fL-, pt+ environment have poor surface sensitivity relative to internal sensitivity compared to those at high halide ion concentrations and low pH, are not high contrast, and are particularly susceptible to excess The stability when AEON Yoshikuroji changes in the same way, that is, the stability of production, is remarkable h5
It can be seen that

Actual Mii Example-2 In the preparation of milk 1'ill R of Actual Mii Example-1, pAg
Milking powders I and J were prepared by fixing the pH at 3.5 and changing the pH to 1'. Can of Nl19~11,
Ta. After exposure and development as in Example 1, photographic properties were measured. That conclusion IJ! : is shown in Table 4.

As is clear from Table 4 below, it can be seen that the lower the pH, the brighter the sensitivity.

Practical example-3 In the 11 to 1 mixing method, pr( was set to 2.0 and three types of conventional twinned polydisperse emulsions were obtained by varying the mixing time. Silver iodide 2.0 mol These emulsions contained silver iodobromide emulsions containing L, , M and comparison and 1
After chemically sensitizing emulsion B in the same manner as in Rolling Example-1, apply and dry sample N (L 1.2 to 15 at 71. It was exposed and developed.

↑(I, Jl, milk nlI particles (f-Table-5,
The development results are shown in Table 6.

As is clear from Margin Table 6 below, although the emulsion grains according to 1 of the present invention have a smaller grain size than conventional emulsions,
It can be seen that the surface sensitivity is high.

Actual winding example-4 Silver halide grains formed in the silver excess region at least until the addition of 1/J5M of the total silver hair is completed are silver halide particles formed in the silver excess region by less than 1/15 of gold silver Y. It has a higher surface sensitivity. This actual case illustrates this small fire.

The method for preparing the emulsion in J is the same as in Example 1, but the silver iodide content is different. The only difference is that r is set to 3.0 molar circulation and that the total pAgO value changes.

[Emulsion N]

The pAg at the time of mixing is 3.0, and the pAg is 8.0 after the product is separated.

[Emulsion O]

While adding 1/10 of the total amount of silver, pAg is added at 3.0, and the rest is added at a total pAg of 8.0.

[Emulsion P]

The pAg at the start of mixing was set at 3.0, and was gradually increased as the mixing progressed until 1/10 of the total silver amount was added, resulting in I) Ag'! r4゜5, and pAg is 8 at the end of mixing.
゜O.

[Emulsion Q]

pAg=3.0 while adding 1/20 amount of gold silver tS-
゜Remaining! 7 is added at pAg=8.0.

These emulsions were sensitized, coated, dried, processed and developed in the same manner as in Example 1. The obtained results are shown in Table-7 and Table-
8.

As is clear from J Nu V knee margin table-84), at least the k of gold, silver, and
The silver halide grains formed in the silver-rich region have high surface sensitivity until the addition of 5 fW/l 5 fW is completed.
It can be seen that the contrast) is also insular.

Patent applicant: Konishiroku Photo Industry Co., Ltd., agent patent attorney
Saka 0 Nobuaki (and 1 other person) 28- 1 procedural amendment) 1981 Lo117 I+ Cow 1 Commissioner of the Office Sugi Ao Ten Tono 1 Ko 11 I 11 Display 1982 Special γF If! l□1st 12th:
H171 Jino 3 Correction person 411i! Relationship with 1. Patent applicant (11-1-4, agent 105 Address: 4th floor, Goto Building, 2-6-10 Toramon, Minato-ku, Tokyo %'501-1444 5 Date of amendment order Initiation 6. Number of inventions increased by amendment 7. Specification subject to amendment (detailed explanation column) 8. Contents of amendment As shown in the attached sheet Contents of amendment 1. 1 area in line 9 of cylinder 400 of the description is Next, 1 silver ion and halide ion add -1.

2. On page 8, line 14, 1a degrees -1 is corrected to "interparticle distance."

3 Patent application No. 1, 1973-145, page 12, lines 6 to 7
022" has been corrected to 1 JP-A-55-70837".

4 Patent application No. 12, line 7 to line 8, 1972-692
No. 42” is U special 1 no L month IA 55-161.2
No. 30”.

5 1 Patent Application 1984-104940 on page 12, line 11
``No.'' has been amended to read ``Unexamined Japanese Patent Publication No. 54-48520''.

2. 1-

Claims (4)

[Claims] (1) In the method for producing negative-working silver halide photographic emulsions by the double jet method, until at least one-fifteenth of the total silver infiltration is added, the pAg value is 2 to 5, and the pAg value is 2 to 5.
A method for producing a negative-working silver halide photographic emulsion, characterized in that the H value is maintained at 1 to 4. (2) Claim No. 1 which is characterized in that the rate of addition of water-soluble silver salt and water-soluble halogen (?) is increased continuously or stepwise as the silver halide grains grow. A method for producing a negative-working silver halide photographic emulsion as described in item 1. (3) A negative-working silver halide photograph according to claim 1 or 2, characterized in that at least 80 jib of the silver halide grains has a diameter within ±40 coefficients of the average grain diameter. Method of manufacturing emulsion. (4) Il' characterized in that the silver halide photographic emulsion is reduction sensitized, sulfur sensitized and/or gold sensitized;
! A method for producing a negative-working silver halide photographic emulsion according to any one of items 1 to 3.