Radiation imagery chemistry: process – composition – or product th – Radiation sensitive product – Identified radiation sensitive composition with color...
Reexamination Certificate
2001-03-22
2004-03-30
Baxter, Janet (Department: 1752)
Radiation imagery chemistry: process, composition, or product th
Radiation sensitive product
Identified radiation sensitive composition with color...
C430S570000, C430S630000
Reexamination Certificate
active
06713243
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a silver halide photosensitive containing a high-boiling-point organic solvent which is excellent in such properties as solubility, dispersibility, and dispersion stability. More specifically, the present invention relates to a silver halide photosensitive material in which deterioration of color developability after storage and deterioration of storability of emulsions or latent images are alleviated.
Heretofore, a compound which is photographically useful and has low solubility in water was is incorporated into a hydrophilic colloid layer by being dissolved in a suitable oil droplet-forming agent, i.e., a high-boiling-point organic solvent, and thereafter being dispersed in a solution of a hydrophilic organo-colloid such as gelatin in the presence of a surfactant.
2. Description of the Related Art
A silver halide photosensitive material normally comprises a support having thereon a photosensitive layer and a non-photosensitive layer containing a photographically useful compound. In order to incorporate a compound which is photographically useful and has low solubility in water into the photosensitive layer and/or non-photosensitive layer, a process hitherto practiced comprises the steps of dissolving the photographically useful compound in a suitable oil droplet-forming agent, i.e., a high-boiling-point organic solvent, dispersing the solution containing the compound in a solution of a hydrophilic organo-colloid such as gelatin in the presence of a surfactant, and coating the dispersion on a support so that a hydrophilic organo-colloid layer containing the photographically useful compound is formed.
Since the high-boiling-point organic solvent, which is used for the formation of the hydrophilic organo-colloid layer, is used as a solvent for a hydrophobic compound in the formation of a constituent layer of a silver halide photosensitive material, and since the high-boiling-point organic solvent remains in the constituent layer after formation thereof, the high-boiling-point organic solvent is required to exhibit a wide range of performances as indicated below. That is, the high-boiling-point organic solvent has excellent capability to dissolve a photographically useful compound, as well as affinity for, dispersibility in, and dispersion stability in gelatin; the high-boiling-point organic solvent does not decrease the reactivity of the photographically useful compound (e.g., color developability of a coupler or redox reactivity of a redox compound such as a color mixing preventive); the high-boiling-point organic solvent can control the hue to be formed by a color-forming reaction to an optimum; the high-boiling-point organic solvent itself has excellent chemical stability; the high-boiling-point organic solvent does not accelerate decomposition of the photographically useful compound to be dispersed or yellowing of a white background due to decomposition; the high-boiling-point organic solvent does not accelerate fading of the dye to be formed due to light, heat, moisture, or atmosphere; the high-boiling-point organic solvent does not accelerate occurrence of colored stains which are caused by processing components remaining in the photosensitive material after processing; the high-boiling-point organic solvent does not adversely affect the storability of emulsions and latent images; and the high-boiling-point organic solvent is inexpensive and can be easily obtained.
Heretofore, phthalic ester was widely known as a high-boiling-point organic solvent for a silver halide photosensitive material. However, high-boiling-point organic solvents based on phthalic ester presented problems due to migration of the high-boiling-point organic solvent in the photosensitive material during storage.
The migration during storage can be inhibited by increasing of the molecular weight of the phthalic ester or by enhancement of hydrophobicity of the phthalic ester. But the high-boiling-point organic solvent having a larger molecular weight brings about the problem that reactivity of the photographically useful compound, for example color developability of a coupler, is reduced. Therefore, it has been difficult to attain inhibition of diffusion and preservation of reactivity at the same time.
Meanwhile, for further improvement of performances, development of new high-boiling-point organic solvents has been made. An example of such compounds is a compound having a plurality of ester linkages such as a dibenzoate. Examples of such compounds include the compounds described in, for example, Japanese Patent Application Laid-Open (JP-A) Nos. 1-101543, 2-43541, 2-77060, 3-191345, 3-192347, 4-146433, and 59-83154, and European Patent No. 969320. However, these compounds do not necessarily satisfy the requirements described above. In addition there is still, a need for attainment of the inhibition of the diffusion and the preservation of reactivity of the photographically useful compound.
At the same time, the development of a high-boiling-point organic solvent that causes little damage to the environment and can replace a phthalic ester has been desired.
SUMMARY OF THE INVENTION
A first object of the present invention is to provide a silver halide photosensitive material which uses a high-boiling-point organic solvent capable of sufficiently dissolving a compound having low solubility in water and providing excellent dispersibility and dispersion stability of the compound and which produces durable colored images and reduces the formation of colored stains. A second object of the present invention is to provide a silver halide photosensitive material in which the fogging and soft-toning of the emulsion during storage are alleviated. A third object of the present invention is to provide a silver halide photosensitive material in which the storability of latent images is improved. A fourth object of the present invention is to provide a silver halide photosensitive material in which undesirable effects that may be caused by the migration of a dispersing medium are inhibited. A fifth object of the present invention is to provide a silver halide photosensitive material in which problems due to conventional high-boiling-point organic solvents can be solved using an inexpensive high-boiling-point organic solvent. A sixth object of the present invention is to provide a silver halide photosensitive material in which the starting materials to be used for the manufacture cause little damage to the environment.
After close studies of a dibenzoate-based compounds and triester-based compounds, the present inventors have found that a compound having a specific structure enables the realization of the above-mentioned inhibition of the diffusion and the preservation of reactivity at the same time and satisfies all the requirements for a high-boiling-point organic solvent of a silver halide photosensitive material. Based on this finding, the inventors have achieved the present invention.
The problem described above can be solved by a silver halide photosensitive material containing at least one noncoloring compound represented by any one of the following general formulae (a) to (d):
[In the general formula (a), Ra
1
and Ra
2
each independently represents an unsubstituted alkyl group having 1 to 10 carbon atoms. L
1
represents a group represented by the following general formula (a2) or (a3). n and p each independently represents an integer of 1 to 5. Where L
1
is a group represented by the general formula (a3), the total number of carbon atoms of Ra
1
, Ra
2
, Ra
7
, and Ra
8
is 5 or greater.]
[In the general formula (a2), Ra
3
, Ra
4
, Ra
5
, and Ra
6
each independently represents a hydrogen atom or an unsubstituted alkyl group having 1 to 10 carbon atoms and m represents an integer of 2 to 4. Ra
3
, Ra
4
, Ra
5
, and Ra
6
may be the same as or different from each other. If m is 2 or greater, the total number of carbon atoms of Ra
1
, Ra
2
, Ra
3
, Ra
4
, Ra
5
, and Ra
6
is 5 or greater.]
[In the g
Matsuda Naoto
Mikoshiba Hisashi
Yoneyama Hiroyuki
Baxter Janet
Fuji Photo Film Co. , Ltd.
Walke Amanda C.
LandOfFree
Silver halide photosensitive material does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Silver halide photosensitive material, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Silver halide photosensitive material will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3187832