JP2000305228A - Color photographic film having high blue-sensitivity - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance contract without sacrificing image form sensitivity. SOLUTION: A layer (a) among the blue-recording layer unit of this color photographic film contains most sensitive silver halide grains for forming a latent image and having a bromide content of >50 mol% of silver and a corresponding circle diameter of 0.05-0.5 μm and a content of random oriented silver halide grains (having not adsorbed a blue-absorbing dye) of 0.00-0.5 g/m2, and a blue light reflective layer (b) is located so as to receive the light from the layer (a) that contains flat silver halide grains containing no blue absorbing dye and having a thickness of 0.12-0.15 μm and an average aspect ratio of >15 and a coating-attached amount of 0.4-1.5 g/m2 and a bromide content of >50 mol%, and this layer (b) is contained in the blue-recording layer unit, and the total coating amount of the flat silver halide grains in the blue light reflective layer (b) and the randomly-located silver halide grains in the layer (a) is >=0.5 g/m2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION Color photographic elements exhibiting high blue sensitivity are disclosed. Specifically, the present invention relates to a color photographic element using a radiation sensitive silver halide emulsion for the blue recording layer unit and the minus blue recording layer unit.

Definition of Terms The term "equivalent circular diameter" or "ECD" is used to indicate the diameter of a circle having the same projected area as a silver halide grain. The term "aspect ratio" refers to the ratio of the grain ECD to grain thickness (t). The term "tabular grain" refers to a grain that has two parallel crystallographic planes that are significantly larger than any other crystallographic planes, and that has an aspect ratio of at least 2. The term "tabular grain emulsion" refers to an emulsion in which tabular grains account for greater than 50% of total grain projected area.

[0003] The term "{111} tabular" when referring to grains and emulsions indicates that the tabular grains have parallel major crystal faces that extend into the {111} crystal faces. The term "equiaxed" when referring to a grain indicates that there are no stacking faults in the crystal plane such as twin planes and screw dislocations inside the grain. The term "randomly oriented" indicates that no orientation pattern is observed on the crystal planes of the silver halide grains.

The term "high bromide" in referring to grains and emulsions indicates that bromide is present at a concentration of greater than 50 mole percent, based on total silver. When referring to silver halide grains and emulsions containing two or more halides, the halides are named in ascending order of concentration.

The terms "blue,""green," and "red" refer to 400-500 nm, 500-600 nm, and 600-7, respectively.
2 shows a portion of the visible spectrum located within the wavelength range of 00 nm. The term “minus blue” refers to the visible portion of the spectrum other than the blue portion of the spectrum, and refers to any spectral region, for example, in the range of 500-700 nm. The term "half peak absorption bandwidth" refers to the region of the spectrum where the dye exhibits an absorption equal to at least half of its peak absorption.

[0006] The terms "front" and "back" indicate positions closer or further away, respectively, from the source of exposure radiation than the support. The terms “above” and “below” indicate a position that is closer or farther, respectively, from the source of the exposure radiation.

[0007] The term "subject" means the person (s) to be photographed and / or the object (s). The term "stop" in a photographic speed comparison is required to produce the same reference density
Shows 0.3 log E exposure difference (E is exposure (lux second)
Is). The term “maximum gamma” as used herein is defined as the highest value of the ratio ΔD / ΔE measured,
Is the increase in density that occurs in response to an increase in exposure .DELTA.E. Contrast is the integral of gamma over the selected exposure range of interest.

[0008]

2. Description of the Related Art Photographic images that allow the reproduction or approximation of the natural hue of a subject are conventionally captured on photographic film mounted in a camera. High bromide silver halide emulsions are generally used for camera sensitive films. Separate images of each of the blue, green, and red exposures are captured in blue, green, and red recording layer units in the film. The blue recording layer unit is a chemically sensitized high bromide, which may be based on intrinsic blue sensitivity or sensitized to the blue region of the spectrum by one or more blue absorbing spectral sensitizing dyes. Contains particles. The green recording layer unit contains chemically sensitized high bromide particles sensitized to the green region of the spectrum by one or more green absorption spectral sensitizing dyes. The red recording layer unit contains chemically sensitized high bromide grains sensitized to the red region of the spectrum by one or more red absorption spectral sensitizing dyes. Dye-forming couplers are generally included in these layer units and allow a distinct hue dye image to be formed during color processing. If the photographic film is intended to be reversaled to produce a visible color positive image, or if the photographic film is intended to be used for the exposure of color paper, blue, green and The red recording layer unit contains a coupler that forms a blue absorbing (yellow) image dye, a green absorbing (magenta) image dye, and a red absorbing (cyan) image dye, respectively. For the purpose of reading dye image information from photographic film by digital scanning, the dye images may be of any hue as long as they are distinguishable.

[0009] The components used to construct the color photographic film are Research Disclosure (Researc).
h Disclosure), Volume 389, September 1996, Item 389
57. Research Disclosure
Over it is, Kenneth Mason Publications, Ltd., Dudley Hou
se, 12 North St., Emsworth, Hampshire P010 7DQ, Eng
Published by land. The following headings of item 38957 are of particular relevance to the present invention.

I. Emulsion grains and their preparation (particularly the last sentence of paragraph (1) of B. Grain morphology); II. Vehicles, vehicle extenders, vehicle-like addenda and vehicle related addenda; IV. Chemical sensitization; V Spectral sensitization and desensitization A. Sensitizing dyes; VII. Absorbing and scattering materials A. Reflecting materials (particularly relevant); X. Dye image formers and modifiers (excluding A. Silver dye bleach); XI. Layers and layer arrangements XII. Features applicable only to color positive (C. Color positives derived from color negatives); XV. Supports.

US Pat. No. 5,300,413 to Sutton et al. Discloses a high bromide {111} tabular grain emulsion having a controlled grain dispersity and thickness to promote blue light reflection.

The research disklo cited above .
Ja, E. of item 38957 Blends, layers and p
In erformance categories, (7), the recording layer unit is
General methods of splitting into two, three, or more emulsion layers with different sensitivities are contemplated. If you do this,
Generally, the fastest emulsion layer is first coated to receive exposure radiation because this increases sensitivity. Paragraph (7) also states that "higher contrast can be obtained by coating a lower sensitivity emulsion layer on a higher sensitivity emulsion."

[0013]

As image capture color photographic films have been constructed with ever-increasing photographic speeds, the speed and sharpness of blues compatible with negative blue (ie, green and red) image recordings. It has become difficult to obtain image records. One cause of this problem is said to result from the low ratio of sunlight blue photons. Illumination with a tungsten filament (a very common artificial light source) is significantly deficient in blue photons.
The most common way to increase the photographic sensitivity of the blue dye forming layer unit is to increase the average volume of silver halide grains introduced. Unfortunately, it is well recognized in the art that increasing each stop in sensitivity by increasing particle size can be expected to increase image granularity by 7 particle units. Also, although it is generally known that the contrast of a photographic image can be enhanced by coating a lower sensitivity emulsion layer over a higher sensitivity emulsion layer, this "reversal" of the conventional order of emulsion layers is This method of increasing contrast is not widely used because it improves contrast at the expense of imaging sensitivity.

[0014]

SUMMARY OF THE INVENTION In one embodiment, the present invention comprises a transparent film support and a coupler coated on the support to form first, second, and third image dyes, respectively. Comprising blue, green, and red recording layer units, wherein the blue recording layer units are coated to receive exposure radiation prior to the green and red recording layer units, Each of the layer units contains radiation sensitive silver halide grains for forming a developable latent image upon imagewise exposure, containing more than 50 mole percent bromide relative to silver; And each of the first, second, and third image dyes has a half-peak occupying at least one 25 nm spectral region not occupied by other first, second, and third image dyes. Absorption band Wherein the blue recording layer unit is arranged to receive light from a layer in the blue recording layer unit containing a latent image forming silver halide grain of maximum sensitivity. The blue light-reflective layer contains no blue-absorbing dye, has a thickness in the range of 0.12 to 0.15 μm, an average aspect ratio of more than 15, and a coating weight of 0.4 to 1.5 g / m ^2. Having tabular silver halide grains formed from bromide in an amount of more than 50 mol% with respect to silver, and the layer containing the latent image forming silver halide grains having the maximum sensitivity. Further comprises more than 50 mol% bromide with respect to silver, has an equivalent circular diameter in the range of 0.05-0.5 μm, has no blue-absorbing dye adsorbed, and is a randomly oriented halide. The silver particles are also 0.00-0.5 g / m ²
Are contained, the tabular silver halide grains in the blue light reflecting layer and the silver halide grains randomly oriented in the layer containing the latent image forming silver halide grains having the maximum sensitivity. For color photographic elements having an overall coating coverage of at least 0.5 g / m ² on silver.

In a preferred embodiment of the present invention, the layer containing the latent image forming silver halide grains having the maximum sensitivity comprises bromide in an amount of more than 50 mol% with respect to silver,
It contains 0.01 to 0.5 g / m ^{2 of} randomly oriented silver halide grains having an equivalent circular diameter in the range of 0.5 μm and having no blue absorbing dye adsorbed thereon.

In a further preferred embodiment of the present invention,
The blue recording layer unit contains at least three layers, the first and second layers being a latent image that can be developed in reactive association with a coupler that forms a first image dye. Wherein the first layer is arranged to receive the exposing radiation prior to the second layer, and the radiation-sensitive silver halide in the first layer is formed. The silver halide grains have a lower maximum sensitivity than the radiation-sensitive silver halide grains in the second layer, the silver coating weight of the first layer is in the range of 0.1 to 0.7 g / m ² ,
Further, the blue light reflecting layer is arranged to receive the exposure radiation after the second layer.

By adding a blue light reflecting layer below the blue light recording layer containing the silver halide grains having the maximum sensitivity, the sensitivity of the blue light recording layer unit is further increased, and the blue recording layer unit and the lower layer are formed. It has been found that the image resolution of the image produced by the minus blue recording layer unit is only slightly reduced, if at all. Accordingly, the present invention enhances the sensitivity of blue exposure recording without causing the expected degree of image deterioration in the dye image forming layer unit.

Quite unexpectedly, the addition of randomly oriented grains for scattering blue light to the blue light recording layer containing the silver halide grains of maximum sensitivity is expected. It has been found that the sensitivity is increased to a higher degree than that of the dye image forming layer unit, and that even if there is image deterioration in the dye image forming layer unit, the degree is further reduced.

By reversing the order of the emulsion layers from high sensitivity to low sensitivity commonly used in combination with other described structural features, the contrast of the blue record is high and the blue sensitivity is high. It has further been found that very little color photographic elements can be obtained with a loss of color.

[0020]

DETAILED DESCRIPTION OF THE INVENTION The simple construction of a color photographic element satisfying the requirements of the present invention is illustrated below.

[0021]

Each of the blue, green, and red recording layer units incorporates high bromide silver halide grains for forming a latent image during imagewise exposure. Preferably, these high bromide particles each contain more than 70 mole percent bromide, optimally more than 90 mole percent bromide, based on silver. Although these particles can form latent image sites on the surface, inside, or both of the particles, it is preferred to form latent image sites primarily on the surface of the particles. The portion of silver halide not occupied by silver bromide
It can be any convenient conventional concentration of silver iodide and / or silver chloride. Silver iodide can be present up to its solubility limit in silver bromide (generally referred to as 40 mole% based on silver). However, iodide concentrations of less than 20 mol% are preferred, and iodide concentrations of less than 10 mol%, based on silver, are most preferred. Preferably, the silver chloride concentration is limited to less than 30 mole percent, optimally less than 10 mole percent, based on silver. Silver iodobromide compositions are particularly preferred. Other contemplated grain compositions include silver bromide, silver chlorobromide, silver iodochlorobromide, and silver chloroiodobromide. Latent image forming silver halide grains are described in Research Data , cited above.
Office closures, I. Emulsion grai of item 38957
It can take the form as disclosed in ns and their preparation.

In a particularly preferred embodiment, at least the latent image forming silver halide grains in the minus blue (ie, green and red) recording layer units are provided by chemically and spectrally sensitized {111} tabular grain emulsions. Provided. Non-tabular grain emulsions are often used in blue recording layer units for latent image formation in combination with minus blue layer units in which tabular grain latent image forming emulsions have been incorporated, but similar Latent image forming silver halide grains can also be used in the blue recording layer unit. Specific examples of high bromide tabular grain emulsions are provided by the following patents.

List T Daubendiek et al., US Pat. No. 4,414,310; Abbott et al., US Pat. No. 4,425,426; Wilgus et al., US Pat. No. 4,434,226; Maskasky, US Pat. U.S. Pat.No. 4,433,048; Evans et al. U.S. Pat.No. 4,504,570; Yamada et al. U.S. Pat.No. 4,647,528; Daubendiek et al. U.S. Pat. U.S. Pat.No. 4,672,027; Daubendiek et al., U.S. Pat.No. 4,679,745; Daubendiek et al., U.S. Pat.No. 4,693,964; Maskasky U.S. Pat.

Sugimoto US Patent 4,755,456; Goda US Patent 4,775,617; Saitou et al. US Patent 4,797,354; Ellis US Patent 4,801,522; Ikeda et al. US Patent 4,806,461; Ohashi et al. U.S. Pat.No. 4,835,322; Makino et al., U.S. Pat.No. 4,835,322; Daubendiek et al., U.S. Pat.No. 4,914,014; Aida et al., U.S. Pat. U.S. Pat.No. 5,061,616; Tsaur et al., U.S. Pat.No. 5,147,771; Tsaur et al., U.S. Pat.No. 5,147,772; Tsaur et al., U.S. Pat. 5,210,013;

US Pat. No. 5,250,403 to Antoniades et al .; US Pat. No. 5,272,048 to Kim et al .; US Pat. No. 5,310,644 to Delton; US Pat. No. 5,314,793 to Chang et al .; US Pat. U.S. Patent No. 5,334,495; Chaffee et al. U.S. Patent No. 5,358,840; Delton U.S. Patent No. 5,372,927; Daubendick et al. U.S. Patent No. 5,576,168; Olm et al. Maskasky U.S. Patent No. 5,604,085; Reed et al. U.S. Patent No. 5,604,086; Eshelman et al. U.S. Patent No. 5,612,175;

Levy et al., U.S. Pat.No. 5,612,177; Wilson et al., U.S. Pat.No. 5,614,358; Eshelman et al., U.S. Pat.No. 5,614,359; Maskasky, U.S. Pat. U.S. Patent 5,667,954; Maskasky U.S. Patent 5,667,955; Maskasky U.S. Patent 5,691,131; Maskasky U.S. Patent 5,693,459; Black et al. U.S. Patent No. 5,726,007; Irving et al. U.S. Patent No. 5,728,515; Bryant et al. U.S. Patent No. 5,728,517; Maskasky U.S. Patent No. 5,733,718; Jagannathan et al. Brust et al., U.S. Patent No. 5,763,151; and Maskasky et al., U.S. Patent No. 5,792,602.

In general, the above {111} tabular grain emulsions contain {111} tabular grains having more than 50% of total grain projected area;
It preferably accounts for more than 70%, optimally more than 90%. High bromide emulsions in which {111} tabular grains account for substantially all (> 97%) of the total grain projected area are disclosed and specifically contemplated in the List T patents cited above. . The {111} tabular grains preferably have an average thickness of less than 0.3 μm, most preferably less than 0.2 μm. It is specifically contemplated to use ultrathin tabular grain emulsions in which tabular grains having a thickness of less than 0.07 μm account for greater than 50% of total grain projected area.

When a latent image is formed in the blue recording layer unit by the tabular grain emulsion, these tabular grains can have the above-mentioned thickness characteristics. However, to gain sensitivity by absorbing blue light in these particles,
It has been observed that tabular grains having a thickness of up to 0.50 μm can account for at least 50% of the total grain projected area in the blue recording layer unit.

The high bromide {111} tabular grains preferably have an average aspect ratio of at least 5, preferably greater than 8. Average aspect ratios generally range from 12 to 60, though may range over 100 or more. The average ECD of the latent image forming emulsions is generally less than 10 μm, with an average ECD of less than 6 μm being particularly preferred to maintain a low level of granularity.

The latent image forming high bromide emulsion is chemically sensitized.
Any of the above cited Research Disclosure , Item 38957, IV. Chemical sensitization, and the chemical sensitizations of the patents in List T above can be used. One or a combination of sulfur, selenium, and gold sensitizers are commonly used. Furthermore, epitaxial sensitization of the grains is contemplated.

In all cases, the latent image forming particles in the minus blue recording layer unit are spectrally sensitized. The green recording layer unit contains one or a combination of green absorption spectral sensitizing dyes adsorbed on the surface of the latent image forming particles. The red recording layer unit contains one or a combination of red absorption spectral sensitizing dyes adsorbed on the surface of the latent image forming grains. The latent image forming particles of the blue recording layer unit can be based solely on the original blue sensitivity, especially if the particles contain iodide. Preferably, the blue recording layer unit contains one or a combination of blue absorbing spectral sensitizing dyes adsorbed on the surface of the latent image forming grains. Spectral sensitizing dyes and combinations of spectral sensitizing dyes are described in Research Disclosure , Item 38957, V.A.
Spectralsensitization and desensitization, A. Sen
sitizing dyes, as well as those disclosed in the List T patents.

In addition to the silver halide grains, the dye image forming layer unit contains a dye image forming coupler for forming an image dye following imagewise exposure and color processing. If the photographic element is intended to be used for exposure of color photographic paper or to form a reversible color image that can be viewed, the blue, green, and red recording layer units may be And dye-forming couplers that form yellow, magenta, and cyan image dyes, respectively. If the photographic element is intended for scanning, any convenient hue of the image dye can be applied to the blue, green, and red recording layer units as long as the image dye can be identified by inspection or scanning. Any of them can be formed. To facilitate scanning, each image dye does not overlap the half peak absorption bandwidth of any image dye in another recording layer unit;
It is contemplated to exhibit a half peak absorption bandwidth of at least 25 nm, preferably 50 nm. Dye image forming couplers are available from Research Disclosure , Item 38957, X.
Dye image formers and modifiers, B. Image-dye-for
It can take any of the various forms disclosed in the ming couplers.

The blue recording layer unit (I) is divided into at least two layers.

[0035]

The latent image forming layer can be constituted as described above. The reflective layer contains high bromide tabular grains. In order to exhibit a blue light reflecting function, the high bromide tabular grains can take any of the above-described silver halide compositions for the image recording layer unit. further,
The silver halide grains in the reflective layer are completely free of blue absorbing dyes, especially blue absorbing spectral sensitizing dyes.

In order to promote the reflection of blue light, the blue light reflecting layer contains tabular silver halide grains having a selected thickness range of 0.12 to 0.15 μm. In this thickness range, tabular grains reflect much more blue light than minus blue light. Tabular grains in the selected thickness range are further selected to exhibit an average aspect ratio of greater than 15, preferably greater than 20, and most preferably greater than 30. Therefore, the average ECD of these particles is in all cases above 1.8 μm. It is generally taught that latent image forming tabular grains should have an average ECD of 10 μm or less. This is because beyond this level, the granularity will be unacceptably high for most, if not all, imaging applications. This limitation on the maximum average ECD does not apply at all to the silver halide grains in the reflective layer when these grains do not form any dye image and therefore have no effect on the image granularity in the recording layer unit. .
Thus, the maximum ECD of the selected thickness of tabular grains can range up to the limits convenient for emulsion production. For example, average ECDs as high as 15 or 20 μm are contemplated. As the average ECD of the particles increases,
The particles are less occupied by edges (eg, portions of the particle volume within 0.1 μm of the edges), and the specularity of light transmission and reflection is higher. This contributes to increasing the image sharpness in the blue and minus blue recording layer units.

The tabular grains in the selected thickness range are present together with silver halide grains which are non-tabular or tabular but exhibit a thickness deviating from the selected thickness range and are used in the reflective layer. It is also possible. For example, a silver halide emulsion in which tabular grains in a selected thickness range are precipitated together with other grains can be introduced into the reflective layer. The presence of particles outside the selected thickness range increases the overall silver coverage and reduces the overall efficiency of the reflective layer. Therefore, it is preferable to minimize the presence of particles outside the selected thickness range. Preferably, tabular grains in the selected thickness range account for more than 70%, most preferably more than 90%, of the total grain projected area in the reflective layer. Tabular grain emulsions can be easily precipitated with very small variations in tabular grain thickness, so that tabular grains within the selected thickness range account for more than 99% of total grain projected area. It is possible to precipitate occupying tabular grain emulsions.

The teachings of the List T patents allow for the preparation of tabular grain emulsions for use in reflective layers, and the following patents specifically teach high proportions of tabular grains. Sait
o Other U.S. Pat.No. 4,797,354; Tsaur et al. U.S. Pat.
No. 5,147,771, No. '772, No.' 773, No. 5,171,659,
No. 5,210,013; and Antoniades et al., U.S. Pat.
No. 50,403. U.S. Pat.No. 5,334,469 to Sutton et al.
An improvement based on other teachings, further illustrating the choice of tabular grain thickness within a selected range.

The latent image forming layer of the blue recording layer unit, in addition to at least one type of particle group containing the latent image forming particles having the above-described characteristics, has the object of scattering blue light in the latent image forming layer. May further contain a group of silver halide grains provided for the above. Such light scattering particles, based on silver, preferably 0.01 to 0.5 g / m ^2, and more preferably is applied at a coverage of 0.05~0.35g / m ^2. These light scattering particles are randomly oriented as coated in the latent image forming layer and increase light scattering as compared to light reflection or transmission. These particles can be of any convenient conventional crystalline form that can remain randomly oriented as applied. This excludes the use of tabular grain emulsions to provide light scattering grains. It is well recognized that tabular, rod-like, and other needle-like grains have their main crystal axes oriented parallel to the support surface. Preferred light scattering particles are equiaxed particles, including octahedral, cubic, tetradecahedral, rhombic dodecahedral, and spherical particles. Alternatively, these grains can be non-tabular, non-equiaxed grains, for example, multiple twin grains. If the ratio is small, tabular grains can be tolerated, but are preferably excluded from the light scattering particle group.

In order to promote light scattering, the particles are 0.05%
~ 0.5 μm, preferably 0.1-0.35 μm, optimally 0.15
It is contemplated to exhibit an ECD in the range of 0.20.25 μm. Light scattering particles can be co-precipitated with other particles and applied. Of course, it is possible and preferred to minimize the presence of grains that deviate from the desired ECD range. Preferably, greater than 90% of the total silver is in the desired ECD range for any light scattering particles in any emulsion to be combined with the latent image forming particles. It is possible to precipitate emulsions in which substantially all (> 99%) of the grains are equiaxed grains within the desired ECD range.

A blue light reflecting layer containing tabular grains in a selected thickness range, coated at a coverage of 0.4 to 1.5 g / m ² , and a random orientation of 0.00 to 0.5 g / m ² Significant improvements in blue sensitivity can be achieved using a layer containing the highest sensitivity latent image forming silver halide grains containing silver halide grains. The total coating weight of the tabular silver halide grains in the blue light reflecting layer and the randomly oriented silver halide grains in the layer containing the latent image forming silver halide grains having the highest sensitivity is , At least 0.5 g / m ² with respect to silver. Therefore, in the absence of the randomly oriented scattering emulsion grains in the layer containing the most sensitive latent image forming silver halide grains, selected layers coated with a coverage of at least 0.5 g / m ² are preferred. The blue light reflecting layer must contain tabular grains in the thickness range described above. Tabular grains and randomly oriented silver halide grains are
It is contemplated that the coatings will be applied over a range of 1.5 and 0.5 g / m ² or less, and are only useful for very specialized applications, although higher coating coverages are possible.

The grains located in the reflective layer and the light scattering grains (if present) in the latent image forming layer and the latent image forming grains in the latent image forming layer are all high bromide silver halide grains having the above-mentioned composition. It is. Furthermore, the reflective layer is completely free of blue absorbing dyes, especially blue absorbing spectral sensitizing dyes. The light scattering particles in the latent image forming layer also have no adsorbed blue light absorbing dye (for example, spectral sensitizing dye).

The silver halide grains in the blue light reflecting layer preferably do not participate in the formation of a dye image. No latent image is formed in the blue reflective layer when (a) the image dye-forming coupler is not present in the reflective layer and / or (b) when the silver halide grains in the reflective layer are not chemically sensitized. . Alternatively, it is possible to introduce an image dye-forming coupler to chemically sensitize silver halide grains in the blue light reflecting layer. In this case, although the blue light reflecting layer is involved in latent image formation, it exhibits only low image sensitivity due to the absence of the blue absorption spectral sensitizing dye. The blue light reflective layer is in all cases less sensitive than the overlying latent image forming layer.

Light scattering particles (if present) in the latent image forming layer have no adsorbed blue light absorbing dye (for example,
They have not been spectrally sensitized). Light scattering particles may also be free of chemical sensitization. It is specifically contemplated to use light scattering particles that do not participate in latent image formation. Light scattering particles, when they participate in latent image formation, are contemplated to be less sensitive than latent image forming particles formulated with them. The light scattering particles are in all cases at least one stop (0.30 log) greater than the latent image forming particles.
E), preferably at least 2 stops (0.6 log E)
Low sensitivity.

In another specifically contemplated form, the blue recording layer unit is divided into at least three layers.

[0047]

The high-sensitivity and low-sensitivity latent image forming layers are (I
Although it can be constituted in the same manner as the latent image forming layer of I), the difference is that the sensitivity is different between the high-sensitivity layer and the low-sensitivity layer. The light scattering particles (if present) are preferably confined in the sensitive latent image forming layer. When the reflective layer also participates in latent image formation, the reflective layer has a lower sensitivity than the low-sensitivity latent image forming layer. Furthermore, the low-sensitivity latent image forming layer
It is also possible to divide into two or more layers having different sensitivities. When two or more silver halide emulsion layers having different sensitivities are introduced into any one of the recording layer units, they are generally selected so that the sensitivities differ by at least 0.3 logE.

In another form intended to increase the contrast with little or no loss of imaging sensitivity, the blue recording layer unit is divided into at least three layers.

[0050]

In the first (low-sensitivity) and second (high-sensitivity) latent image forming layers, the radiation-sensitive silver halide grains in the first layer are smaller than the radiation-sensitive silver halide grains in the second layer. Configured as above, with the requirement of having a low maximum sensitivity. Therefore, the arrangement of the first and second layers is opposite to the general method of applying a higher sensitivity latent image forming layer on a lower sensitivity latent image forming layer in the recording layer unit. In a conventional layer arrangement of low sensitivity over high sensitivity, the more sensitive layers exhibit a sensitivity over the range of one to three stops higher than the underlying less sensitive layers.
This same relative sensitivity relationship is useful in the practice of this aspect of the invention. However, if the sensitivity of the first layer is somewhat lower than the sensitivity of the second layer, it is possible to increase the contrast, which is within the contemplation of this embodiment. It is customary to make the radiation-sensitive emulsion substantially optimal (see Kofron et al., U.S. Pat. No. 4,439,520 for quantification) because it is customary to chemically and spectrally sensitize the emulsion. The average ECD of the radiation-sensitive silver halide grains is preferably less than the average ECD of the radiation-sensitive silver halide grains in the second layer.

As shown in the examples below, the reversal of the less sensitive latent image forming layer and the more sensitive latent image forming layer of the coating arrangement of high sensitivity over low sensitivity introduces other changes. If performed without this, a significant degradation in imaging sensitivity is encountered, although the contrast is increased. Combining the inversion layer arrangement with the other two features,
With little or no sacrifice in imaging sensitivity
It has been discovered that a high degree of contrast is possible. One of these other features used to realize the advantages of the inversion layer embodiment of the present invention is that the first latent image forming layer of (IV) has a silver coating coverage of 0.7 g / m ² (preferably 0.6
g / m ² ). The minimum silver coating coverage of the first layer is generally at least 0.1 g / m
² , preferably at least 0.2 g / m ² . A second other feature used to realize the advantages of the inversion layer embodiment of the present invention is the above-mentioned (IV) reflection layer.

If desired, the first (low-sensitivity) latent image forming layer can be divided into two or more layers, both satisfying the requirements of the first layer described above. Similarly, if desired, the second (high sensitivity) latent image forming layer can be split into two or more layers that both satisfy the requirements for the second layer described above. If desired, a third latent imaging layer can be located below the reflective layer. If the reflective layer does not produce image dye, the third layer is useful for expanding the exposure latitude of the blue recording layer unit. The third layer has any convenient silver coating coverage found in the slow emulsion layer of the "triple coat" layer unit (i.e., the layer unit having the fast, medium, and slow emulsion layers). It can be configured similarly to the first layer and the second layer except that it can also have. Generally, the third layer is the first layer
At least one stop (generally 1 to 3 stops) lower than that of the latent image forming layer unit.

Other features of color photographic element (I) can take any convenient conventional form. In addition to silver halide grains and image dye-forming couplers, blue, green,
And the red recording layer unit and all other processing solution permeable layers of the color photographic element (eg, the protective overcoat and antihalation layer unit shown in Element (I)) are processing solution permeable vehicles, generally hydrophilic Sex colloids (eg, gelatin or gelatin derivatives), and vehicle extenders and hardeners (examples of which are described in Research Disclosure , Item 38957 I)
I. Vehicles, vehicle extenders, vehicle-like adden
Listed in da and vehicle related addenda.
The layer containing the latent image forming silver halide grains may be an antifoggant and / or a stabilizer, such as a research disc.
Roger , item 38957, VII. Antifoggants and
It usually contains those listed in stabilizers. The dye image-forming layer contains, in addition to the dye image-forming coupler, other dye image-enhancing additives such as X. Dye image for
Contains image dye modifiers, hue modifiers and / or stabilizers, as summarized in Sections C, D, and E of the mers and modifiers, and solvents for dispersing the couplers and associated hydrophobic additives. be able to. Lisa
Over Ji Disclosure, item 38957 XII. Featu
As explained in res applicable only to color negative, negative-working photographic films generally incorporate dye-forming colored couplers, such as masking couplers.

The antihalation layer unit shown in element (I) is not essential, but is highly preferred for improving image sharpness. The antihalation layer unit can be applied between the red recording layer unit and the transparent film support, or can be applied to the back surface of the transparent film support. In addition to the vehicle to facilitate application, the antihalation layer contains a light absorbing material (generally a pigment) that decolorizes (decolorizes) during processing (these summaries are Research Disclosure ,
Item 38957, VIII. Absorbing and scattering mat
erials, B. Absorbing materials and C. Discharge).

Although a protective overcoat is not required, it is highly preferred to provide physical protection to the blue recording layer unit. In its simplest form, the protective overcoat can consist of a single layer containing a hydrophilic vehicle of the type described above. The protective overcoat is
A convenient place to include coating aids, plasticizers and lubricants, antistatics and matting agents (a summary of these can be found in Research Disclosure , Item 38957).
IX. Coating and physical property modifying addend
a)). In addition, Research Disclosure
Jar , item 38957 UV dyes / optical brightener
As described in s / luminescent dyes, UV absorbers are often placed on protective overcoats. Often, the protective overcoat is divided into two layers, with the additives located between these layers. It is also common practice to place a layer similar to a protective overcoat on the backside of a support containing surface property modifying additives. When the antihalation layer is applied to the back side of the support, it is usual to introduce a surface modification additive into this layer.

To prevent color contamination of the blue, green and red recording layer units, an oxidized developing agent scavenger (also known as a stain inhibitor) is introduced into these layer units to prevent oxidation. It is a common practice to prevent the transferred color developing agent from migrating from one layer unit to an adjacent layer unit. Preferably, the oxidized color developing agent is located in a separate layer (not shown in (I) above) at the interface of these layer units. Pollution control agent, Research Disclosure , Item 38957
D. Hue modifiers / stabilization, paragraph (2).

It is also preferred that a blue filter material such as a processing solution bleachable yellow dye or silver curryare be disposed in the layer between the latent image forming particles in the blue recording layer unit and the adjacent layer unit. These filter materials are also available in Research Disclosure , Item 38957 VI
II. Absorbing and scattering materials, B. Absorbi
ng materials and C. Discharge.

It has been specifically identified that the reflective layer is a convenient and preferred location for the placement of the stain inhibitor. Therefore, it is possible to configure the reflective layer so as to exhibit a plurality of functions, thereby avoiding an increase in the total number of layers required for forming the color film.

The transparent film support can take any convenient conventional form. It is generally understood that film supports also include a subbing layer disposed on the film to improve the adhesion of the hydrophilic colloid layer.
Characteristics of the conventional transparent film supports, Research disk
Roger , item 38957 XV. Supports (2),
These are summarized in (3), (4), (7), (8), and (9).

When color photographic films are intended to be scanned for either reading an image or reading information incorporated at the time of manufacture to aid in exposure or processing, they are: , Research Day
Scan facilita , closure , item 38957 XIV.
Features may be included, such as those described by ting features. If a magnetic recording layer is introduced into the color film, it is preferably located on the back side of the film support.

The color films of the present invention are specifically contemplated for use in cameras used to capture visible light images of photographic subjects. Exposure can range from high intensity short exposure to low intensity long exposure. Since the present invention provides the ability to increase blue sensitivity, shorter exposures with lower illumination are specifically contemplated.
For example, the present invention is particularly suitable for the production of color films having an ISO rating higher than 200, preferably higher than 400 and optimally higher than 1000. These color films can be used in a camera intended for repeated use or a camera whose use frequency is limited (for example, a single use camera). A contemplated feature of cameras with a limited number of uses is the research display.
Closure , Item 38957, disclosed in (2) of XVI. Exposure.

Once imagewise exposed, the color photographic films of the present invention can be processed in any convenient conventional manner to correspond to the latent images in the recording layer unit, or to produce these latent images. On the other hand, an inverted dye image can be produced. Most commonly, a negative emulsion is introduced into a recording layer unit that produces a color negative dye image when subjected to a single color development step. When the recording layer unit is directly replaced with the positive emulsion, a positive color image, that is, reproduction of a photographed object is generated by a single color developing process. When a negative emulsion is introduced into the recording layer unit, a positive dye image can be generated by reversal processing (color development is performed following black-and-white development). A description of conventional color processing systems can be found in Research Disclosure , Item 38957, XVIII. Chemical development systems.
B. Color-specific processing systems.

A particularly preferred processing system is Kodak Flex
icolor ^TM C-41 method. U.S. Patent No. 5,914,225,
As described by US Pat. Nos. 5,935,767 and 5,902,721, the color film and the method may be modified to enable improved results with less than 2 minutes development time. Is contemplated.

The foregoing discussion of the color photographic element (I) and the blue recording layer unit suggests that if each of the blue, green, and red recording layer units contains a single latent image forming emulsion layer, No further elaboration is required. Element (I)
In, each of the green and red recording layer units can contain two, three, or more emulsion layers with different sensitivities. When the emulsion layer containing the most sensitive grains is coated above the other emulsion layers of the recording layer unit, a higher speed than when those emulsions are incorporated in a single layer is obtained. Is achieved. When the emulsion layer containing the most sensitive grains is coated below the other emulsion layers of the recording layer unit, higher contrast is obtained than when the emulsions are incorporated in a single layer. Is achieved.

In the color photographic elements of the present invention, it is specifically contemplated to coat the reflective layer directly below the emulsion layer containing the fastest grains, ie, the fastest emulsion layer. If one or more further latent image forming emulsion layers are arranged in the blue recording layer unit, they may be coated below the reflective layer. The reflective layer will reflect back some of the blue light that may have been able to expose any underlying blue recording layer (s), but nonetheless, Sufficient blue light to pass through the reflective layer to expose the blue recording layer (s) at the right.

Although it is common practice to place the green recording layer unit closer to the source of the exposing radiation than the red recording layer unit, the location of the green and red layer units in element (I) Can be replaced. It is also possible to provide more than one recording layer unit for recording exposures of the same hue in a single element.

For example, the preferred layer arrangements where the more sensitive and less sensitive red and green recording layers are incorporated into a single color photographic element are shown below.

[0069]

[0070] Yet another alternative arrangement is illustrated below.

[0071]

In the color photographic element (VI), the high-sensitivity blue recording layer unit is constituted as described above. The slow blue recording layer unit can also be constructed as described above, or the reflective layer can be omitted. In element (VI), the blue filter will indeed reduce the exposure of the low-sensitivity blue recording layer unit, so that the high-sensitivity green recording layer unit and the high-sensitivity red recording layer unit can be used without using the blue filter at all. Protected from blue light exposure. However, it is also possible to arrange the blue filter material between the slow blue recording layer unit and the slow green recording layer unit. Most of the image dyes are formed in the low-sensitivity green recording layer unit and the low-sensitivity red recording layer unit, though this layer arrangement causes some blue light contamination of the high-sensitivity green exposure record and the high-sensitivity red exposure record. Thereby, blue light contamination of the green exposure record and the red exposure record can be minimized.

Although elements (V) and (VI) are shown and described above as "double coated" units having high and low sensitivity recording layer units, by analogous construction element (V) And (VI) can be modified to include a "triple coat" unit. 1 (V variant) or 3 (VI variant) blue recording layer units, 3
It is also contemplated to combine one green recording layer unit and three red recording layer units.

[0074]

The present invention can be better understood with reference to the following specific embodiments. Component coating coverages (in parentheses) are reported in units of g / m ² . Silver halide coating coverage is based on silver mass. The suffix E indicates an element satisfying the requirements of the present invention, and the suffix C indicates an element for comparison.

[0075]

Embedded image

[0076]

Embedded image

[0077]

Embedded image

[0078]

Embedded image

[0079]

Embedded image

[0080]

Embedded image

Color Elements A series of color photographic elements 1-10 were constructed with only the composition of layer 3B being varied. In the comparative element 1C, the reflective layer 3B was omitted. In the other elements, Layer 3B contained gelatin (1.077) and OxDS-1 (0.0154), and the choice of reflective particle size and coating coverage was as reported in Tables I and IA below. . The grains in Layer 3B were silver bromide tabular grains in each case where tabular grains of the desired thickness accounted for 99.9% of the total grain projected area. These elements were hardened with bis (vinylsulfonyl) methane hardener (0.27) which was evenly distributed throughout all of the gelatin containing layers. The antifoggant 4-hydroxy-6-methyl-1,3,3a, 7-tetraazaindene is used, and these elements contain other conventional additives which do not vary from element to element and do not participate in dye image formation. For example, surfactants, high boiling solvents, coating aids, sequestering agents, lubricants, matte beads, and tint dyes.

Layer 1 (protective overcoat layer): gelatin (0.871).

Layer 2 (UV filter layer): silver bromide Lippmann emulsion (0.215), UV-1 (0.114) and UV-2 (0.0
22), and gelatin (0.860).

Layer 3 (high-sensitivity yellow layer): Blue-sensitive (by BSD-1) silver iodobromide non-tabular emulsion (1.72) having an ICD of 9 mol% and an ECD of 2 μm, based on the total Ag, YC-1 ( 0.08
8), YC-2 (0.234), gelatin (2.0).

Layer 3B (reflective layer): particles shown in Tables I and IA.

Layer 4 (low sensitivity yellow layer): two types of blue-sensitive (all according to BSD-1) tabular grain silver iodobromide emulsion,
(I) 1.3 mol% of I based on total Ag and ECD of 2.7 mol%
μm × t is 0.13 μm (0.484) and (ii) total Ag
Is 1.3 mol%, and ECD is 1.6 μm × t
Formulation with 13 μm (0.323), yellow dye-forming couplers YC-1 (0.464), YC-2 (0.099), IR-1 (0.0
42), and gelatin (1.58).

Layer 5 (Yellow filter layer): YFD-1
(0.151), YFD-2 (0.043), OxDS-1 (0.108), and gelatin (0.645).

Layer 6 (high-sensitivity magenta layer): 4 mol% of iodide based on Ag, ECD of 3.4 μm × t of 0.11 μm
m green sensitivity (by mixture of GSD-1 and GSD-2) tabular grain silver iodobromide emulsion (1.032), magenta dye-forming coupler MC-1 (0.088), MC-2 (0.011), MC-3 (0.00
3), masking coupler MM-1 (0.022), and gelatin (1.25).

Layer 7 (middle magenta layer): 4.5 mol% of iodide based on Ag, ECD of 1.2 μm × t of 0.14
μm green-sensitive (by mixture of GSD-1 and GSD-2) silver iodobromide tabular grain emulsion (1.28), magenta dye-forming coupler MC-2 (0.074), MC-3 (0.022), MC-4 (0.10
6), Masking coupler MM-1 (0.048), IR-2 (0.01
0), and gelatin (1.42).

Layer 8 (low-sensitivity magenta layer): 0.3 mol% of iodide based on Ag, ECD of 0.7 μm × t of 0.14
μm green sensitivity (by mixture of GSD-1 and GSD-2) silver iodobromide tabular grain emulsion (0.484), magenta dye-forming coupler MC-2 (0.069), MC-3 (0.021), MC-4 (0.09
9), masking coupler MM-1 (0.086), and gelatin (0.914).

Layer 9 (interlayer): OxDS-1 (0.110) and gelatin (1.08).

Layer 10 (high speed cyan layer): Two red-sensitive (by a mixture of RSD-1 and RSD-2) silver iodobromide tabular grain emulsions, (i) 4.0% by mole of I to Ag , EC
D is 3.0 μm × t is 0.12 μm (0.634) and (i
i) I based on Ag is 4.5 mol% and ECD is 1.3 μm
Xt is 0.14 μm (0.333), cyan dye-forming coupler CC-1 (0.060), yellow dye-forming coupler YC-2 (0.022), masking coupler CM-1 (0.02)
7), bleach accelerator releasing coupler B-1 (0.044), and gelatin (0.882).

Layer 11 (low sensitivity cyan layer): two red-sensitive silver iodobromide tabular grain emulsions (all from mixtures of RSD-1 and RSD-2), (i) 4.5 mol% I to Ag
Where ECD is 1.3 μm × t is 0.14 μm (0.950)
And (ii) I to 3.5 mol% of Ag and ECD
A compound with 1.0 μm × t of 0.11 μm (0.674),
Cyan dye-forming coupler CC-1 (0.409), yellow dye-forming coupler YC-2 (0.022), masking coupler CM-1
(0.011), bleach accelerator releasing coupler B-1 (0.065),
IR-3 (0.017), IR-4 (0.026), and gelatin (1.
72).

Support: cellulose triacetate having a back layer of carbon black.

Performance Comparison Density (D) for each of the blue, green, and red color records
The above elements were subjected to the same stepwise exposure so that a characteristic curve of exposure to light (log E) could be plotted. Exposure to the British Journal of Photogra
phy Annual , 1988, pp. 196-198.
k Processed by Flexicolor ^™ C-41 color negative method.

The blue dye images were analyzed and compared for sensitivity (reported below in relative log units; a difference of 0.01 log E in sensitivity equals one relative log sensitivity unit). Sensitivity was measured at the foot density Ds (Ds minus Dmin is 20% of the slope of the line drawn between Ds and the point D 'on the characteristic curve 0.6 log E away from Ds. equal).

The sharpness difference is reported in CMT (cascaded modulation transfer) units.
The equations underlying the CMT are based on James' Theory of
thePhotographic Process , 4th Ed., Macmillan, New Y
ork, 1977, p. 629, and a more qualitative explanation can be found in Keller's Science and Technology of Photograph.
Title Modula starting on page 175 of y, VCH, New York, 1993
It is provided under tion Transfer Function. Negative CMT differences indicate loss of sharpness.

Sensitivity and sharpness were based on Comparative Element 1C.

Table I — Element Layer 3B Δ Blue Sensitivity Δ Green CMT Δ Red CMT １ 1C None Not applicable Not applicable Not applicable 2C ECD 4.94μm +2 −0.7 −0.7 × t 0.14 μm (0.431) 3E ECD 4.94 μm +10 −0.7 −0.6 × t 0.14 μm (0.862) 4E ECD 4.94 μm +11 −1.2 −1.0 × t 0.14 μm (1.29) 5C ECD 1.1 μm +4 −0.8 −1.1 × t 0.14 μm (0.431) 6C ECD 1.1 μm +9 −1.8 −1.8 × t 0.14 μm (0.862) 7C ECD 1.5 μm +11 −2.7 −2.5 × t 0.14 μm (1.29) 8C ECD 1.5 μm +6 −1.0 −1.4 × t 0.14 μm (0.862) 9E ECD 2.7 μm +8 −1.0 −1.2 × t 0.14 μm (0.862) 10C ECD 4.94 μm +3 −0. ^{-0.6 × t 0.14μm (0.862) *} ────────────────────────────────── * on the surface of the particles Adsorbed blue spectral sensitizing dye

Table IA ────────────────────────────────── Δ Blue Sensitivity Δ Blue Sensitivity Element 3B Average ─ ───── 量 Ag deposition amount Aspect ratio ΔGreen CMT ΔRed CMT ──────────────────────────── １ 1C None Not applicable Not applicable Not applicable Not applicable 2C (0.431) 35 2.86 2.86 3E (0.862) 35 14.29 16.67 4E (1.29) 35 9.17 11.0 5C (0.431) 7.9 5.0 3.64 6C (0.862) 7.9 5.0 5.0 7C (1.29) 10.7 4.07 4.4 8C (0.862) 10.76 4.29 9E (0.862) 19.3 8.0 6.67 10C (0.862) ^* 35 4.29 5.0 ───────── * Adsorbed on the particle surface Blue spectral sensitizing dye

From Table IA, it can be seen that Examples 3E, 4E, and 9E, each containing a high bromide tabular grain emulsion having an average tabular grain aspect ratio of greater than 15 with a silver coating coverage of greater than 0.5 g / m ^2. It can be seen that the blue sensitivity per CMT unit of loss of acutance of the green or red record has unexpectedly increased significantly. The minus sign is deleted from the sensitivity / acutance ratio in Table IA.

Comparative element 2C, which lacked 0.5 g / m ² of silver in layer 3B, produced relatively poor results.

Comparative elements 5C, 6C, 7C and 8C using tabular grains having an average aspect ratio of less than 15 gave relatively poor results.

Finally, a comparative element 10 which is identical to element 3E of the example of the present invention except that the blue absorption spectral sensitizing dye is adsorbed on the surface of the silver bromide tabular grains in layer 3B.
C produced relatively poor results.

From these comparisons, it is necessary to combine a plurality of characteristics in order for the reflective layer coated under the blue recording emulsion layer to increase the blue sensitivity while minimizing the decrease in minus blue acutance. It is clear that Not only is it necessary to select tabular grains in a limited thickness range, but if there are no scattering particles in the sensitive blue layer 3, the silver coating coverage for the blue reflective layer should be at least It is also necessary to have an average aspect ratio of at least 15, preferably at least 20, for the tabular grains in this layer of 0.5 g / m ² .

In addition to the addition of scattering particles in the sensitive blue layer 3 in combination with reflective particles which have been shown to be advantageous in layer 3B in Tables I and IA according to a preferred embodiment of the present invention. To illustrate the advantageous effects, a series of color photographic elements 11-21 were constructed with only the composition of Layer 3 and Layer 3B varied from Comparative Element 1C. Scattering and reflective particles were introduced into the elements as shown in Table II.

Table II S = Scattering Particles (AgBr with ECD of 0.22 μm, Layer 3) R = Reflective Particles (AgBr with ECD of 4.94 μm × t of 0.14 μm, Layer 3B) ──────────────────────── Element S / R 青 Blue sensitivity 緑 Green CMT 赤 Red CMT ───────────── ───────────────────── 11C None / None Not applicable Not applicable Not applicable 12C S (0.054) +4 Not measured Not measured / R (None ) 13CS (0.108) +10 Not measured Not measured / R (none) 14CS (0.215) +18 -1.9 -1.4 / R (none) 15CS (0.323) +17 -0.8 -0.0. 9 / R ^{(no) 16E * S (0.108) +24} -0.8 -0.9 / R (0.431) 17E * S (0.108) +18 not measured not measured / R (0.861 18E ^* S (0.0538) +25 not measured not measured ^{/ R (0.861) 19E * S} (0.215) +28 -1.4 -2.6 / R (0.861) 20E S ( no) +8 -0.7 -0 .6 / R (0.861) 21C S (none) +2 -0.7 -0.7 / R (0.431) ──────────────────────── ────────── * Preferred mode

It is clear from Table II that a significant increase in blue sensitivity was realized when either scattering or reflective particles were introduced. Reflective particle coverage of at least 0.4
g / m ² , when used in combination with an overall coverage of at least 0.5 g / m ² , the increase in sensitivity was greater than the increase in sensitivity obtained when scattering and reflecting particles were used separately (Table 1). IIA can better understand).

Table IIA ────────────────────────────────── Δ Blue Sensitivity Δ Blue Sensitivity Element Δ Blue Sensitivity Δ Blue sensitivity 実 合計 Total measured value ΔGreen CMT ΔRed CMT ───────────────────────── {16E ^* + 12 + 24 30 26.7 21C N / A +2 2.9 2.9 19E ^* + 26 + 28 20 10.8 20E N / A +8 11.4 13.3} ─────────────────────────────── * Preferred mode

When comparing element 16E of the example of the present invention with comparative element 21C which has the same amount of reflective particles but no scattering particles, the example of the present invention provides a much greater increase in measured blue sensitivity. It is evident that was observed to occur. The increase in blue sensitivity per unit of CMT change (decrease in acutance) was much greater for the CMT acutance of the green and red records.

Element 19E of a Preferred Embodiment Example of the Invention
Is compared to element 20E of the example of the present invention, which has the same reflective particle coverage but does not use any scattering particles, it can be seen that the preferred embodiment of the present invention results in a much greater increase in measured blue sensitivity. It is clear that it was accepted. The increase in blue sensitivity per unit of CMT change (decrease in acutance) was greater for the green record and less for the red record. The increase in blue sensitivity per unit of CMT change (decrease in acutance) is
Overall, it was larger for the overall minus blue (green and red) record.

According to a preferred embodiment of the present invention, to illustrate the further advantageous effect of the presence of the reflective layer in combination with the inverted high and low speed blue emulsion layers, the above comparisons were made with the following exception. As in the case of the element 1C, the comparison elements 22C and 23C and the element 2 of the example of the present invention.
4E and 25E were prepared.

The comparison element 22C was different from the element 1C only in that the high-sensitivity blue layer 3 and the low-sensitivity blue layer 4 were exchanged (reversed).

The comparison element 23C further reduces the silver loading in the less sensitive blue layer (Layer 4) now coated on Layer 3 to allow the comparison element 22C to be inverted. Configured as a variant. Emulsion (i) in Layer 4 was omitted.

The comparison element 24E was configured as a modification of the element 22C by adding a reflection layer 4B (blue reflection layer) between the inverted high sensitivity blue layer 3 and the yellow filter layer 5.

Element 25E of a Preferred Embodiment Example of the Invention
Was constructed as a modification of the comparative element 23C where the reflective layer 4B was added and the layer was reversed. Thus, only element 25E combined the blue reflective layer with a low silver coverage within the preferred range for layer 4 (which is the first blue absorbing layer in this embodiment).

Layer 4B contains gelatin (1.077) and Ox
DS-1 (0.0154) was included. In the grains in layer 4B, tabular grains of the desired thickness accounted for 99.9% of the total grain projected area in each case, with Ag (0.86), ECD
Was 4.9 μm × t and 0.14 μm as silver bromide tabular grains.

For each of the blue, green and red color records, the above elements were subjected to the same stepwise exposure so that characteristic curves of density (D) versus exposure (log E) could be plotted. Was. Exposure of the exposed elements to the British Journal
Processing was performed by the Kodak Flexicolor ^™ C-41 color negative method described in of Photography Annual , 1988, pp. 196-198.

The blue dye images were analyzed and compared for sensitivity (reported below in relative log units; a difference of 0.01 log E in sensitivity equals one relative log sensitivity unit). Sensitivity was measured at the foot density Ds (Ds minus Dmin is 20% of the slope of the line drawn between Ds and the point D 'on the characteristic curve 0.6 log E away from Ds. equal).

The maximum gamma (γmax) of the above blue characteristic curve
) Was also compared. These results are summarized in Table III.

Table III────────────────────────────────── Element Reflective Layer 4B Low Sensitivity Blue ΔBlue Sensitivity γmax Ag adhesion ────────────────────────────────── 1C None (0.807) Not applicable 0.70 22C None (0.807) -29 0.94 23C Without (0.484) -18 0.84 24E With (0.807) -21 1.09 25E ^{* With} (0.484) +1 0.86 ──────────────────── ────────────── * Preferred mode

From Table III, it can be seen that the blue recording emulsion layer having a high sensitivity and a low sensitivity has been changed from an arrangement having a high sensitivity on a low sensitivity (element 1C) to an arrangement having a low sensitivity on a high sensitivity (22C). Simply swapping (reversing) the position of increases the maximum gamma by 0.24 (a significant amount), but sacrifice 29 relative sensitivity units (0.29 log E, or near maximum stop) It is clear that.

Reducing the silver coating coverage in the less sensitive blue layer above the inverted blue layer configuration (23C) still resulted in a loss of 18 relative sensitivity units despite a 0.10 reduction in maximum gamma. become. In other words, the benefit of gamma and the disadvantage of sensitivity are both offset by a factor of about three.

With the addition of a blue reflective layer to element 22C (element 24E), although the maximum gamma is increased, the loss in sensitivity, although improved, still remains high at 21 relative sensitivity units.

Surprisingly, the silver coating coverage in the slow blue emulsion layer was reduced, and only when the blue reflective layer was used with the inverted blue emulsion layer configuration (25E) was there no loss in speed. A large increase in maximum gamma is maintained. Thus, a photographic element according to this aspect of the invention comprises
High contrast images can be produced with little or no loss of imaging sensitivity. This overcomes one of the major obstacles that has limited the use of a blue recording emulsion layer arrangement with high sensitivity over low sensitivity.

Although the invention has been described in detail with particular reference to certain preferred embodiments thereof, it will be understood that variations and modifications can be effected within the spirit and scope of the invention.

[0127] Other preferred embodiments of the present invention are described below in connection with the claims.

[1] A transparent film support, and the first, second, and third coatings coated on the support, respectively.
Blue, green, containing couplers that form the image dyes of
And a red recording layer unit, wherein the blue recording layer unit is coated so as to receive exposure radiation prior to the green and red recording layer units, and each of the layer units is silver. Contains radiation-sensitive silver halide grains for forming a developable latent image at the time of imagewise exposure, containing more than 50 mol% of bromide,
And each of the first, second, and third image dyes is
A color photographic element exhibiting a half-peak absorption bandwidth occupying at least one 25 nm spectral region not occupied by first, second, and third image dyes other than the dye, wherein the blue recording layer unit is A blue light-reflecting layer arranged to receive light from a layer in the blue recording layer unit containing the latent image-forming silver halide grains of maximum sensitivity, wherein the blue light-reflecting layer Has a thickness in the range of 0.12 to 0.15 μm, an average aspect ratio of greater than 15, and a coating coverage of 0.4 to 1.5 g / m ² , with no blue absorbing dye, The layer containing the formed tabular silver halide grains and containing the latent image forming silver halide grains having the maximum sensitivity described above further contains bromide exceeding 50 mol% based on silver. Contains, 0 The silver halide grains having an equivalent circular diameter in the range of .05 to 0.5 μm and having no blue absorbing dye adsorbed thereon and randomly oriented are also 0.00 to 0.5 g / g.
silver halide which contains m ² and is randomly oriented in the layer containing the tabular silver halide grains in the blue light reflecting layer and the silver halide grains forming the latent image having the maximum sensitivity. A color photographic element having an overall coating coverage with the particles of at least 0.5 g / m ^{2 based} on silver.

[2] The color photographic element of claim 1, wherein the tabular silver halide grains in the blue light reflecting layer are present at a coating coverage of 0.5 to 1.5 g / m ² .

[3] The tabular silver halide grains in the blue light reflecting layer have an average aspect ratio of more than 20.
A color photographic element according to claim 1 or 2.

[4] The tabular silver halide grains in the blue light reflecting layer have an average aspect ratio of more than 30.
A color photographic element according to claim 3.

[5] The color photographic element according to any one of claims 1 to 3, wherein the silver halide grains in each of the layers contain bromide in an amount of more than 70 mol% based on silver.

[6] The color photographic element according to claim 5, wherein the silver halide grains in each of the layers contain more than 90 mol% of bromide with respect to silver.

[7] The method according to any one of claims 1 to 5, wherein the silver halide grains for forming a developable latent image are silver iodobromide.
A color photographic element according to any one of the preceding claims.

[8] The method according to any one of claims 1 to 7, wherein the silver halide particles in the blue light reflecting layer are silver bromide particles.
A color photographic element as described in the item.

[9] The blue recording layer unit contains at least three layers, and the first and second layers of the three layers are in reactive association with the coupler forming the first image dye. A radiation-sensitive silver halide grain for forming a latent image that is capable of being developed and wherein the first layer is arranged to receive exposure radiation prior to the second layer; The radiation-sensitive silver halide grains in the first layer have a lower maximum sensitivity than the radiation-sensitive silver halide grains in the second layer, and the silver coating weight of the first layer is 0.1 to 0.7 g.
/ In the range of m ^2, and the blue light reflecting layer, the second layer is positioned to receive exposing radiation after than, color photographic element according to any one of claims 1 to 8 .

[10] The color photographic element according to claim 9, wherein the silver coating coverage of the first layer is in the range of 0.2 to 0.6 g / m ² .

[11] The layer containing the latent image forming silver halide grains having the maximum sensitivity described above contains bromide in an amount of more than 50 mol% based on silver, and has an equivalent circular diameter in the range of 0.05 to 0.5 μm. And the blue absorbing dye is not adsorbed,
0.01 to 0.5 of randomly oriented silver halide grains
g / m ² containing color photographic element according to any one of claims 1 to 10.

[12] The color photographic element according to claim 11, wherein the randomly oriented silver halide grains are applied to silver in an amount of 0.05 to 0.35 g / m ² .

[13] The color photographic element according to claim 11, wherein the randomly oriented silver halide grains have an equivalent circular diameter in the range of 0.1 to 0.3 μm.

[14] The color photographic element of claim 13, wherein said randomly oriented silver halide grains exhibit an equivalent circular diameter in the range of 0.15 to 0.25 µm.

[15] Particles in which the blue recording layer unit is capable of forming a developable latent image and is arranged to receive blue light passing through the blue light reflecting layer during imagewise exposure. A color photographic element according to any one of the preceding claims, comprising a layer containing

[16] The image dye-forming coupler in the blue recording layer unit forms a yellow image dye, the image dye-forming coupler in the green recording layer unit forms a magenta image dye, and the red recording layer unit The image dye-forming coupler therein forms a cyan image dye.
A color photographic element according to any one of claims 1 to 15.

[17] The color photographic element according to any one of claims 1 to 16, wherein the blue light reflecting layer is free of an image dye-forming coupler.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03C 1/74 G03C 1/74 (72) Inventor Roger A. Bryant United States, New York 14626, Rochester, Stone Fence Road 214

Claims (1)

[Claims] 1. A transparent film support and blue, green, and red recording layers coated on said support and containing couplers to form first, second, and third image dyes, respectively. Wherein the blue recording layer unit is coated so as to receive exposure radiation before the green and red recording layer units, and each of the layer units has a molar ratio of 50 mol to silver. %, Containing radiation-sensitive silver halide grains for forming a developable latent image upon imagewise exposure, containing more than 1% bromide, and the first, second, and third images described above. A color photographic element wherein each of the dyes exhibits a half-peak absorption bandwidth occupying at least one 25 nm spectral region not occupied by the first, second, and third image dyes other than the dye; Blue recording layer The unit comprising a blue light reflective layer arranged to receive light from a layer in the blue recording layer unit containing the latent image forming silver halide grains of maximum sensitivity; Layer has no blue absorbing dye, 0.12-0.15μ
m, average aspect ratio greater than 15, and
A tabular silver halide grain having a coating weight of 0.4 to 1.5 g / m ² , formed from bromide exceeding 50 mol% based on silver, and forming a latent image having the maximum sensitivity described above. In the layer containing silver halide grains,
Furthermore, randomly oriented silver halide grains containing more than 50 mol% of bromide with respect to silver, having an equivalent circular diameter in the range of 0.05 to 0.5 μm, and having no blue absorbing dye adsorbed thereon. also 0.00 to 0.5 g / m ² are contained, randomly oriented in the layer containing the latent image forming silver halide grains in the tabular silver halide grains and the maximum sensitivity of the blue-light reflecting layer The total coating weight with the silver halide grains is at least 0.5 g / m
A color photographic element that is ² .