JPH0157761B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multicolor optical filter that is useful for color image forming devices, and particularly to a color image pickup device or a color image pickup tube, and a method for manufacturing the same.

Polychromatic optical filters are widely used, such as color plates for oblique light flux restriction, color face plates for cathode ray tube displays, plates for photoelectric conversion elements for copying, and filters for single-tube color television cameras. Furthermore, particularly in recent years, with advances in semiconductor manufacturing technology, solid-state imaging devices have come to be used in place of conventional image pickup tubes as elements for converting two-dimensional images into electrical signals. for example
CCD (Charge Coupled Device) or
A solid-state image sensor called a BBD (bucket unit device) has a large number of finely divided light-receiving parts and a drive circuit for extracting information from these light-receiving parts, all housed in one chip, and is used to take color images. In order to accommodate the fine light-receiving surface, a polychromatic optical filter must be provided. As a typical example of such a solid-state image sensor, a polychromatic optical filter used in various fields is used to improve the resolution of color images or to achieve more precise and high resolution as color image conversion devices become smaller. It is also expected to have excellent durability.

Commonly used polychromatic optical filters are red,
Most of them have the primary colors of green and blue or the three primary colors of reflected light of cyan, magenta, and yellow arranged regularly, but some have two colors, four colors, or more. The color elements are commonly arranged in stripes and mosaics. However, these color tones were not suitable.

Some of these conventionally known polychromatic optical filters are manufactured by a vapor deposition method. This vapor deposition method uses an interference filter, in other words, multiple layers of thin films with different refractive indexes are vapor-deposited to a predetermined thickness on a support, and the desired wavelength range (color) is created by the interference effect of light.
A polychromatic optical filter is formed in such a way that it only allows light to pass through. However, the polychromatic optical filter obtained by this method has a different number of layers (usually + several layers) for each adjacent color element (unit photosensitive area).
This method requires a complicated process in which thin films must be deposited to a precise thickness for each layer, resulting in high costs and poor yields.

Another well-known manufacturing method is the so-called dyeing method. The dyeing method is a technique in which polyvinyl alcohol, gelatin, or the like is coated on a support to form a mordant layer (color element receiving layer), and this layer is dyed with a dye. For example, US Pat. No. 3,284,208 describes a method for manufacturing a fine striped filter used in additive color photography using three primary colors using the following steps.
That is, a gelatin layer made photosensitive by adding potassium dichromate is coated on a support, exposed in a pattern, and then washed with warm water to form a relief image. Next, the gelatin layer remaining in the relief image is dyed with a first color dye (red) from a dye solution. Next, after applying an intermediate layer on top of this,
A second gelatin layer to which potassium dichromate has been added is provided, followed by exposure, formation of a relief image, and dyeing with a second color dye (green).
After coating the intermediate layer, a third gelatin layer containing potassium dichromate was applied, and exposed to light.
The steps of forming a relief image and dyeing with a third color (blue) are performed. However, when manufacturing multicolor optical filters using this dyeing method,
The manufacturing process is extremely complex. As a result, many machines have pinholes and scratches that enter them during manufacturing.
Yield will be low. Because of this and the long manufacturing time required, the manufacturing cost of polychromatic optical filters has inevitably become high.

In addition to the above technology, the structure is simple and
Although several proposals have been made regarding the structure and manufacturing technology of polychromatic optical filters that are easy to manufacture and inexpensive, none of them have been satisfactory.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a polychromatic optical filter that has a simple structure, is easy to manufacture, and is inexpensive, and a method for manufacturing the same.

Other objects of the invention will become apparent from the following description of the specification.

The object of the present invention is to provide at least two
In a method for producing a multicolor optical filter comprising a colored layer of layers, a silver halide emulsion containing silver halide and an image dye-providing substance having a hydroxyl group that undergoes oxidation as a function of development of said silver halide. coating at least one layer on the support;
The emulsion layer is subjected to pattern exposure and then the image dye-providing material is developed by development of the silver halide using a developing agent having a hydroxyl group that undergoes oxidation as a function of development of the silver halide under alkaline conditions. At the same time as forming a pattern consisting of the oxidation product and silver, the emulsion in the area where the silver halide development has occurred is hardened by the oxidation product of the developing agent and the oxidation product of the image dye-providing substance; A method for producing a multicolor optical filter, which comprises repeating at least twice a series of steps consisting of removing portions of the emulsion layer in which silver halide development has not substantially occurred with hot water or the like. achieved.

According to a preferred embodiment of the present invention, in the method for manufacturing a multicolor optical filter according to the present invention, desilvering treatment is performed after at least one series of steps, and regarding this desilvering treatment, Performing desilvering treatment after at least one step other than the final series of steps,
Desilvering treatment is also performed after the final series of steps.

Further according to one exemplary embodiment of the invention, a silver halide emulsion and a positive-working first emulsion are deposited on a support.
At least one first emulsion layer containing an image dye-providing substance is coated, the emulsion layer is exposed in a pattern of the first color, and then the image dye-providing substance or its color is coated by silver halide development. A first step of forming a pattern consisting of an oxidation product and silver, and then removing portions of the emulsion layer where the development of silver halide has not substantially occurred with hot water or the like; and at least one second emulsion layer containing a positive-working second image dye-providing substance, the emulsion layer being pattern-exposed to a second color, and then developed by silver halide development. A second step of forming a pattern consisting of an image dye-providing substance or its oxidation product and silver, and then removing portions of the emulsion layer in which development of silver halide has not substantially occurred using hot water or the like; , and a step of performing a desilvering treatment after the step, and the desilvering treatment is carried out after the first step and the second step, respectively. That's true.

The present invention will be explained in detail below.

The support used in the present invention needs to be transparent if it itself becomes a support for an optical filter, but a colored layer is formed on the support and this is used as a support for another transparent support. When transferring onto a body, the support is a temporary support, so it does not need to be transparent and may be translucent or opaque. The support may also be in the form of a plate, a sheet, or a film. Materials for the support include, for example, plastics such as polyethylene terephthalate, polystyrene, polycarbonate, cellulose acetate, glass,
Quartz, saphire, etc. are used. Further, the support itself may have other uses, for example as a face plate of an image pickup tube. Note that the support of the present invention may have an undercoat layer.

Silver halide emulsions advantageously used in the present invention include known silver halide emulsions obtained by dispersing silver halide grains in a water-soluble binder, but fine grain emulsions are particularly preferred for the present invention. For example, a so-called Lippmann emulsion in which the average grain size of silver halide is 0.1 μm or less is desirable. The weight ratio of silver halide to water-soluble binder ranges from about 1:6 to about 8:1. Examples of the silver halide include silver chloride, silver bromide, silver iodide, silver chlorobromide, silver iodobromide, silver chloroiodide, silver chloroiodobromide, and the like. Water-soluble binders include gelatin, albumin, casein, cellulose derivatives, agar,
Examples include sodium alginate, sugar derivatives, polyvinyl alcohol, polyvinylpyrrolidone, polyacrylamide, and others. Compatible mixtures of two or more of these binders are used if desired. The dry thickness of the silver halide emulsion layer is approximately
A range of 0.8 to about 10μ is preferred.

Note that a back layer for antihalation may be provided on the back surface of the present invention, if necessary.

The positive-working image dye-providing substance used in the present invention suppresses the release of diffusible dyes or their precursors in response to an increase in the amount of silver halide developing agent oxidation products. It has the property of decreasing in quantity, and can be classified into the following two types in detail. That is,
(1) Substances that are inherently diffusive under alkaline conditions and turn non-diffusible after oxidation; (2) Substances that are non-diffusible under alkaline conditions and can be hydrolyzed to produce diffusible dyes or their precursors. These are two types of substances that can be released, but are substantially prevented from being released by being oxidized by, for example, a developing agent oxidation product. Here, the substance (1) above is
It is a compound called a dye developer, which is a type of developing agent, and is disclosed in, for example, U.S. Patent No. 2983606.
It is stated in the specification etc. Regarding the substance (2) above, for example, JP-A-51-63618, JP-A-53-63618;
No. 69033, Publications No. 55-88054, U.S. Patent No.
No. 3980479, No. 4108850 and the like.

In the present invention, both of the above two types of image dye-providing substances are advantageously used, but among them, the above-mentioned dye developer (1) is particularly preferably used.

The image dye-providing substance of the present invention is preferably contained in the same layer as the silver halide emulsion. Further, when the colored layer of the present invention is formed, for example, in three layers, it is preferable that the first, second and third image dye-providing substances in each layer have different colors. For example, three colors, yellow, magenta, and cyan, are selected as this color.

The dye developer preferably used in the present invention is:
A compound having both a group of a silver halide developer or its precursor and a group of a dye or its precursor in one molecule, and examples thereof include the following compounds. It goes without saying that these exemplified compounds are useful in the present invention, but the compounds useful in the present invention are not limited thereto.

[Exemplary compounds] The emulsion layer containing the silver halide emulsion and the image dye-providing substance contains a silver halide image developing agent that can migrate through the emulsion layer under alkaline conditions to promote development of the silver halide. It is preferable to add. Examples of such developing agents include methylphenylhydroquinone and the like. The emulsion layer may further contain various silver halide development accelerators, development inhibitors, antifoggants, etc. known in the art.

In the present invention, various black-and-white photographic developers and color photographic developers known in the art can be widely used as the silver halide developer used for developing silver halide. According to a preferred embodiment of the present invention, a dye developer is used as the image dye-providing substance, and methylphenylhydroquinone is further added to the emulsion layer.
In such a case, since the silver halide developing agent is supplied from within the emulsion layer, it is not necessary to add the silver halide developing agent to the alkaline developer in advance.

In addition to the silver halide developing agent, the silver halide developer may contain various additives known in the art, such as a development inhibitor and a development accelerator.

One of the characteristics of the method for producing a multicolor optical filter according to the present invention is that a colored layer (filter color element forming layer) is formed on a support by utilizing the tanning effect accompanying development of silver halide. It is said that The tanning effect is described, for example, in The Journal of Photographic Science (The Journal of Photographic Science).
Journal of Photographic Science), Volume 11,
Tull, published on pages 1 to 26 (1963)
As stated in the paper, etc., among silver halide developing agents, the oxidation products of those containing a hydroxyl group that undergoes oxidation and converts into quinone serve as a binder to crosslink the gelatin contained in the emulsion layer. , to harden the emulsion layer. In the case of the present invention, the emulsion layer that has not been hardened is subjected to pattern exposure (for example, exposed to white light with a striped optical mask in close contact with the emulsion layer),
By performing a development process, a silver image corresponding to the pattern is formed. At this time, in the exposed areas, the emulsion layer is hardened by the action of the oxidation products of the silver halide developing agent and the oxidation products of the image dye-providing substance. On the other hand, the unexposed portions of the emulsion layer remain uncured. Here, the emulsion layer contains an image dye-providing substance having a hydroxyl group that undergoes oxidation as a function of silver halide development; In the emulsion layer, the hydroxyl group undergoes oxidation and converts into an oxidation product that changes to quinone, contributing to the oxidation of gelatin similar to the oxidation product of silver halide developing agent having a hydroxyl group that undergoes oxidation and changes to quinone. , remains in the emulsion layer. On the other hand, in the portions of the emulsion layer where silver halide development has not occurred, the image dye-providing substance is able to migrate under alkaline conditions, and is mainly transported from the emulsion layer into the alkaline developer. I go out and leave. Thus, an image consisting of silver and the oxidation product of the image dye-providing substance is formed in the emulsion layer in response to patterned exposure.

Thereafter, silver and silver halide are removed from the emulsion layer by bleaching and fixing processes, and a colored layer (filter color element forming layer) consisting of the oxidation product of the remaining image dye-providing substance is formed. be able to.

The unexposed portion of the emulsion layer during pattern exposure does not contain the oxidation product of the image dye-providing substance and is transparent, so it may be left as it is as a constituent layer of the multicolor optical filter. However, in order to reduce the possibility of accidents such as contamination as much as possible, it is desirable to remove layers other than those necessary. As mentioned above, due to the tanning effect, in the present invention, the film in the colored part is hardened, while the film in the non-colored part is not hardened. Therefore, the uncolored, uncured portions can be removed with warm water or the like at any stage after the completion of the silver halide development process.

The oxidation product of the image dye-providing substance remaining in the colored layer (filter color element forming layer) of the present invention may be subjected to post-treatment, for example, for stabilization or color adjustment, if necessary. can.

Colored layer of two or more colors (filter color element forming layer)
, the desilvering treatment may be carried out each time each colored layer is formed, or may be carried out all at once after the formation of all colored layers.

To remove silver particles, a bleach solution used in normal color photographic processing is used, and the oxidizing agent is red blood salt, red blood salt,
Examples include dichromate, EDTA complex salt, and the like. For rehalogenation, for example potassium bromide is added.

On the other hand, the fixing agent for silver halide is any well-known silver halide solvent (e.g., sodium thiosulfate, sodium thiocyanate), and the solution containing the fixing agent may optionally contain a preservative (e.g., sodium sulfite). , PH buffer (e.g. boric acid),
PH regulators (eg acetic acid), chelating agents, etc. can be included.

Also, as one of the above desilvering treatments, a one-bath bleach-fix solution, such as a mixed solution of red blood salt and sodium thiosulfate or a mixed solution of iron-EDTA and sodium thiosulfate, can also be used.

When forming colored layers of two or more colors, an intermediate layer can be provided between the colored layer of the first color and the colored layer of the second color, between the colored layer of the second color and the colored layer of the third color, or the like. However, according to the method for producing a multicolor optical filter according to the present invention, surprisingly, even without providing an intermediate layer, the sections between each colored layer were clear and problems such as color mixing did not occur.

According to the method for manufacturing a multicolor optical filter according to the present invention, a color filter having a colored layer with a fine pattern can be easily manufactured, and the resulting filter can also have a simple structure and exhibit sufficient effects. Furthermore, since the colored layer uses an oxidation product of an image dye-providing substance that can remain in the emulsion layer as a function of silver halide development, the boundaries between each colored layer are clear and the coloring Even if the layer is made thinner, sufficient optical density can be obtained.

Hereinafter, the present invention will be explained in more detail based on Examples.

Example 1 80g of gelatin and silver bromide particles with an average diameter of about 0.06μ
To a silver bromide emulsion containing 80 g, 1.2 g of the exemplary compound [C-1] and methylphenylhydroquinone were added.
0.6 g was added, and this liquid was coated on a transparent plate glass support to a thickness of about 3 μm and dried.
A striped optical mask with a transparent portion having a width of 25 μm and a pitch of 50 μm was brought into close contact with a sample of the photosensitive material thus produced, and white light (tungsten lamp) was irradiated thereon. Next, this sample was developed using the following alkaline solution at 23° C. for 2 minutes.

[Alkaline liquid]

Sodium sulfite (anhydrous) 1g Sodium hydroxide 0.4g Sodium sulfate 6g Finish with water.

After washing for 5 minutes, the sample was soaked in warm water at 50℃ for 1 hour.
immerse for a minute to remove the unexposed silver bromide emulsion layer,
Next, silver whitening treatment was carried out at 20°C for 2 minutes using the following whitening solution.

[Bleach solution]

Potassium ferricyanide 100g Potassium bromide 30g Water 1000ml After washing with water for 2 minutes, it was processed using the following fixing solution (20°C, 2 minutes).

[Fixer]

Sodium thiosulfate 240g Sodium sulfite 3g Glacial acetic acid 5ml Potassium alum 6g Water 1000ml Washed with water for 5 minutes and then dried. A filter sample having a cyan stripe colored layer with a width of 25 microns was thus obtained.

Example 2 1.2 g of the exemplified compound [C-2] and methylphenylhydroquinone were added to the same silver bromide emulsion as in Example 1.
0.6 g was added, coated on a transparent plate glass support to a thickness of about 3 μm, and dried. A sample of the photosensitive material thus produced was subjected to the same processing steps as in Example 1 to obtain a filter sample having a cyan stripe colored layer. However, the alkaline solution for development processing used in Example 1 was replaced with the following one.

[Alkaline liquid]

Sodium hydroxide 2.0g Sodium sulfite (anhydrous) 1.0g Sodium sulfate 6.0g Finish with water.

Example 3 For each filter sample obtained in Examples 1 and 2, the following colored layer was formed on the colored layer. That is, 1.2 g of the exemplified compound [Y-2] and 0.6 g of methylphenylhydroquinone were added to the same type and amount of silver bromide emulsion as in Example 1, and this was added to the silver bromide emulsion obtained in Examples 1 and 2 above. Each colored layer was overcoated to a thickness of 3μ.

Exposure was performed on the gap between the cyan stripe colored layers. Next, a yellow stripe colored layer was formed in the same manner as in Example-1.

In this way, a striped multicolor optical filter according to the present invention having two colored layers of cyan and yellow each having a width of 25 μm was obtained.

In each of the obtained polychromatic optical filters, the boundaries between each colored layer were clear, no color mixing was observed, and sufficient optical density could be obtained.

Claims (1)

[Claims] 1. A method for producing a multicolor optical filter comprising at least two colored layers on a support, comprising: silver halide; and an image dye-providing substance having a hydroxyl group that undergoes oxidation as a function of development of the silver halide. Coating on a support at least one silver halide emulsion layer containing hydroxyl groups, pattern exposing the emulsion layer and then developing a silver halide containing hydroxyl groups which undergo oxidation as a function of development under alkaline conditions. At the same time, a pattern consisting of the oxidation product of the image dye-providing substance and silver is formed by developing the silver halide using the developing agent, and at the same time, the emulsion in the area where the silver halide development has occurred is A series of steps consisting of curing by an oxidation product and an oxidation product of the image dye-providing substance, and then removing the emulsion layer in the portion where silver halide development has not substantially occurred by using hot water or the like. A method for producing a multicolor optical filter, comprising repeating the steps at least twice.