When a silver halide color photographic material is imagewise exposed and developed by an aromatic amine color developing agent, dye images are formed by the reaction of dye image-forming coupler(s) (hereinafter simply referred to as coupler(s)) and the oxidation product of the color developing agent formed as the result of development. For a multicolor photographic material, a combination of a yellow coupler, a cyan coupler, and a magenta coupler is usually used.
Since Fischer et al's discovery of how to conduct a color development process in 1912, the system has been strikingly improved. In particular, recently the improvements in shortening of photographic processing time, simplification of processing steps, reutilization of waste processing liquids, reduction of amounts of replenishers for processing liquids, photographic processing without using a wash step, removal of benzyl alcohol from the color developer to prevent environmental pollution, etc., have been actively investigated.
However, even with such efforts, there remain various problems. For example, there are in fact problems due to using replenishers for processing liquids in accordance with the processing amount of color photographic materials in place of preparing fresh processing liquids.
That is, for color photographic processing, a color developer, a stop liquid, a bleach liquid, a fix liquid (or a bleach-fix liquid or a blix liquid), etc., are usually used but the compositions for these processing liquids change due to decomposition of the processing components, such as a developing agent, etc., during processing for a long period of time, since the processing temperature is generally maintained at 31.degree. C. to 43.degree. C. to speed up processing, oxidation of the processing components by contact with air, accumulation of dissolved matters of the components in color photographic materials by processing with the processing liquids, and also addition of processing liquid carried by color photographic materials from the previous step to form so-called running liquids.
Accordingly, replenishment for supplementing chemicals consumed by processing to each processing liquid and regeneration of each processing liquid by removing therefrom useless materials have been performed, but the aforesaid problems have not yet been satisfactorily solved by the application of these counterplans.
Furthermore, in the process of reducing the amount of wash water or omitting the wash step due to a shortage of water resources or an increase of water charges, as well as due to prevention of environmental pollution, inorganic components such as thiosulfates, sulfites, metabisulfites, etc., in processing liquids and organic components such as a color developing agent, etc., are contained in or attached to color photographic materials processed.
In view of the deterioration of the compositions used in processing liquids and the aforesaid problems in reducing the amount of wash water in the wash step or in omitting the wash step, it can be seen that there is a tendency to increase the amounts of components used for processing liquids which results in an increase in the amounts carried in the color photographic materials after development.
On the other hand, with regard to couplers, the development of couplers giving clear cyan, magenta, and yellow dyes having less side absorptions for obtaining good color reproducibility and also the development of high-active couplers for completing color development in a short period of time have been developed. Furthermore, the development of various additives for obtaining good performance of these couplers has been also found. However, such coupler performance causes the color photograph to have reduced storage stability, because these couplers react with the processing liquid components remaining in the color photographic materials after processing.
It is known that when processing liquid components remain in color photographic material after processing, an aromatic primary amine compounds, which is a color developing agent, and the compounds induced from the amine compound reduce the fastness of color images under the influence of light, moisture, oxygen, etc., or are converted into colored substance by self-coupling thereof or reaction with coexisting materials to cause a so-called "stain" during storage of the color photographic materials thus processed for a long period of time. This is a fatal defect for color photographs.
On the other hand and apart from this, various investigations into preventing the deterioration of color images formed and preventing the formation of stain have also been made. For example, it has been proposed to selectively use couplers showing less fading property, use fading preventing agents for preventing fading of color photographs by light, and use ultraviolet absorbents for preventing the deterioration of color images by ultraviolet rays.
In these proposals, the effect of preventing the deterioration of color images by the use of fading preventing agents is large and as such fading preventing agents, there are, for example, hydroquinones, hindered phenols, tocopherols, chromans, coumarans, and the compounds formed by etherifying the phenolic hydroxy groups of these compounds as described in U.S. Pat. Nos. 3,935,016, 3,930,866, 3,700,455, 3,764,337, 3,432,300, 3,573,050, 4,254,216, British Patents 2,066,975, 1,326,889, Japanese Patent Publication No. 30462/76, etc.
These compounds may have an effect of preventing fading and discoloration of dye images, but since the effect is yet insufficient for meeting the customers' requirement for high image quality and the use of these compounds changes the hue, forms fogs, causes poor dispersibility, and causes fine crystals after coating silver halide emulsions, overall excellent effects for color photographs have not yet been obtained by the use of these compounds.
Furthermore and recently, for preventing the occurrence of stain, the effectiveness of certain amine compounds are proposed in U.S. Pat. Nos. 4,463,085, 4,483,918, Japanese Patent Application (OPI) Nos. 218445/84, 229557/84, etc. (the term "OPI" as used herein refers to a "published unexamined Japanese patent application"). However, by the use of these proposed compounds, a satisfactory effect for preventing the occurrence of stain has not yet been obtained.
USPTO Backgrounds
USPTO Backgrounds