Radiation imagery chemistry: process – composition – or product th – Radiation sensitive product – Two or more radiation-sensitive layers containing other than...
Reexamination Certificate
2000-05-26
2002-04-30
Letscher, Geraldine (Department: 1752)
Radiation imagery chemistry: process, composition, or product th
Radiation sensitive product
Two or more radiation-sensitive layers containing other than...
C430S558000, C430S550000, C430S570000, C430S581000, C430S585000, C430S587000
Reexamination Certificate
active
06379878
ABSTRACT:
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is based upon and claims the benefit of priority from the prior Japanese Patent Applications No. 11-149800, filed May 28, 1999; and No. 2000-048220, filed Feb. 24, 2000, the entire contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
The present invention relates to a silver halide color photosensitive material and, more particularly, to a silver halide color photosensitive material having improved color reproduction.
Recently, silver halide color photosensitive materials are strongly required to have superior color reproduction in addition to high sensitivity with which photographing is possible, high sharpness, and high graininess.
In particular, purplish colors which reflect light having longer wavelengths than 580 nm are reproduced as colors much more reddish than the actual ones. It is pointed out that one cause of this inconvenience is that the maximum sensitivity wavelength of the spectral sensitivity distribution of red-sensitive layers of many color photosensitive materials for photographing, e.g., many color reversal films, is much longer than 605 nm (in many cases longer than 640 nm) which is the wavelength of the spectral sensitivity peak of the longest wavelength of three sensory organs of the human eye. For the purposes of obtaining faithful color reproduction and providing a photographing sensitive material which does not largely changes its color reproduction during photographing under various light sources, U.S. Pat. No. 3,672,898 has disclosed a method of restricting the spectral sensitivity distributions of blue-, green-, and red-sensitive layers to certain ranges. According to this patent, purplish hue reproduction can be effectively improved by shifting the spectral sensitivity distribution of a red-sensitive layer to a shorter wavelength and approaching the maximum sensitivity wavelength of the spectral sensitivity distribution of that red-sensitive layer to 605 nm.
Unfortunately, the following problems arise in providing a color film which faithfully reproduces the hue and perceived chroma of an object to be photographed by shifting the spectral sensitivity distribution of a red-sensitive layer to a shorter wavelength.
First, when the spectral sensitivity wavelength of a red-sensitive layer is shortened, purple is faithfully reproduced. However, the sensitivity of this red-sensitive emulsion layer to red light becomes insufficient, so the color reproduction of red becomes cyanic and this lowers the saturation. As a method of solving this problem and improving both the saturation and the hue reproduction, Jpn. Pat. Appln. KOKAI Publication No. (hereafter referred to as JP-A-)62-49354, whose corresponding U.S. application is now patented to U.S. Pat. No. 4,764,456, has disclosed a method of using pyrazoloazole couplers as magenta couplers. Also, JP-A-2-124566 has proposed a method of improving saturation by enhancing the interlayer effect to red-sensitive emulsion layers in a color reversal photosensitive material, thereby improving both hue and faithfulness. Furthermore, in examples of this publication the use of 2-equivalent pyrazolotriazole couplers is described.
When, however, the present inventors examined the application of 2-equivalent pyrazoloazole couplers to color reversal photosensitive materials, it turned out that the saturation of red did not improve as expected and green became impure to lower its saturation when 2-equivalent pyrazoloazole couplers were used in green-sensitive layers, compared to conventionally used 4-equivalent pyrazolone magenta couplers. When the spectral sensitivity of a red-sensitive emulsion layer is shortened, the saturation of red and green naturally lowers. Therefore, a further lowering of the saturation of green is a serious problem when the spectral sensitivity wavelength of a red-sensitive emulsion layer is relatively shortened.
A method which uses an asymmetrical trimethinecyanine dye (e.g., one is a benzoxazole derivative and the other is a benzothiazole derivative) as represented by formula (I) described in JP-A-2-124566, whose corresponding U.S. application is now patented to U.S. Pat. No. 5,024,925, is an effective means for shortening the wavelength of the spectral sensitivity distribution of a red-sensitive layer. Also, JP-A-62-49354 describes in its examples the combined use of sensitizing dyes in this category and 2-equivalent pyrazoloazole couplers. However, when the present inventors used 2-equivalent pyrazoloazole magenta couplers and also used large amounts of sensitizing dyes effective to wavelength shortening in in red-sensitive layers, the sensitizing dyes remained after development and colored white portions. Since coloration of white portions in particularly color reversal photosensitive materials largely impairs the product value, coloration after processing is unallowable, so a certain solution is being strongly demanded. On the other hand, the use of 4-equivalent pyrazoloazole couplers in color reversal photosensitive materials is disclosed in, e.g., JP-A-63-153548, whose corresponding U.S. application is now patented to U.S. Pat. No. 4,994,351. However, this JP-A-63-153548 has not disclosed the difference between the color reproduction effects of 2- and 4-equivalent couplers and the combination of these couplers with the aforementioned sensitizing dyes. That is, the problems which the present inventors encountered, i.e., the problem of color reproduction of 2-equivalent pyrazoloazole couplers or of the combination of 2- and 4-equivalent pyrazoloazole couplers and the problem of coloration of white portions caused by residual sensitizing dyes are unknown problems.
BRIEF SUMMARY OF THE INVENTION
It is an object of the present invention to provide a silver halide color photosensitive material having improved reproduction of hue and perceived chroma and, more specifically, to apply this material to a color reversal photosensitive material which is subjected to reversal processing and color development after black-and-white development.
The above object of the present invention is achieved by the following.
(1) A silver halide color photosensitive material having at least one blue-sensitive emulsion layer, at least one green-sensitive emulsion layer, and at least one red-sensitive emulsion layer on a support, wherein the red-sensitive emulsion layer has the maximum value of sensitivity in a wavelength region of 580 nm to 650 nm, and the green-sensitive emulsion layer contains at least one magenta coupler represented by formula (MC-1) below:
wherein R
1
represents a substituent selected from the group consisting of a secondary or tertiary alkyl group, an aryl group, an alkoxy group, an aryloxy group, an amino group, an acylamino group, an arylthio group, an alkylthio group, an aminocarbonylamino group, an alkoxycarbonylamino group, a carbamoyloxy group, and a heterocyclic thio group. These substituents may be substituted or unsubstituted. Each of G
1
and G
2
represents a nitrogen atom or a carbon atom. When G
1
is a nitrogen atom, G
2
is a carbon atom; when G
2
is a nitrogen atom, G
1
is a carbon atom. R
2
substitutes one of G
1
and G
2
which is a carbon atom, and represents a substituent. A group represented by formula (MC-1) can further substitute via R
1
or R
2
to form a polymer. Also, a group represented by formula (MC-1) can bond to a polymer chain via R
1
or R
2
.
(2) A silver halide color photosensitive material having at least one blue-sensitive emulsion layer, at least one green-sensitive emulsion layer, and at least one red-sensitive emulsion layer on a support, wherein the red-sensitive emulsion layer contains a sensitizing dye represented by formula (SD-1) below at a molar ratio of 10% to 100% with respect to all the sensitizing dyes in the layer, and the green-sensitive emulsion layer contains at least one magenta coupler represented by formula (MC-1) described in item (1):
wherein Z
1
represents an atomic group necessary to form a heterocyclic ring selected from the group consisti
Matsuda Naoto
Mikoshiba Hisashi
Nakamura Tetsuo
Shimura Yoshio
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