JPS62192036A - Information recording medium - Google Patents

Abstract

PURPOSE:To improve the shelf life of a recording medium and to provide high sensitivity and high density thereto by inducing the colorations which are identifiable from each other for each of picture elements in a silver salt color photographic emulsion layer thereby recording information. CONSTITUTION:This recording medium is constituted of, for example, a transparent base 11, and the color photographic emulsion layer 12 and protective layer 13 provided thereon or the base 21 formed with a reflection layer 24 on the surface and the color photographic emulsion layer 22 and protective layer 23 provided thereon. The layers 12, 22 may be made into a combination of 2 colors in addition to 3 colors. The preset binary or higher colorations identifiable from each other are induced for each of the picture elements constituted by the blocks between dotted lines and the information to be recorded is recorded by the digital signal set in accordance with the difference in the rate of coloration per specified area. The shelf life is improved and the medium which permits the information recording with the high sensitivity and high density is obtd. according to the above-mentioned constitution.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of the Invention] The present invention relates to an information recording medium from which information can be read by optical means. More specifically, the present invention relates to an information recording medium in which digital signals are recorded on a silver halide thread photographic emulsion layer.

[Technical Background of the Invention] In recent years, information recording media that use high energy density beams such as laser light have been developed and put into practical use.

This information recording medium is called an optical disk, and is used as a video disk, an audio disk, a large-capacity still image file, a large-capacity computer disk memory, and the like.

An optical disk has a basic structure consisting of a disk-shaped substrate made of glass, synthetic resin, etc., and a recording layer made of a metal or semimetal such as Bi, Sn, In, Te, etc., provided on the substrate.

Conventionally, information on optical discs is recorded by arranging digital signals into binary areas with different optical characteristics, consisting of unchanged areas of the recording layer and areas of disappearance of the recording layer (for example, bits and holes), that is, so-called This was done by recording using a binary signal recording method.

In recent years, there has been an increasing demand for increased recording capacity for optical discs, and countermeasures such as increasing the density of the recording area have been taken. Therefore, there is a limit to its increase.

This is because recording is performed using heat during laser beam irradiation. This is because when the cell spacing reaches the submicron range, there is no material that can insulate with a submicron thickness.

Therefore, on the other hand, research is also being conducted to try to increase the recording capacity of optical discs by other methods.

For example, Japanese Patent Laid-Open No. 58-137148 discloses that the recording capacity of an optical disc can be increased by digitally recording information in a negative information recording layer by arranging a signal train exhibiting an integer number of states of three or more. The basic expression IJ1 is disclosed. Specifically, this invention provides a recording layer with three or more values, including an unchanged area (an unrecorded area), a recording layer disappearing area (pit), and an area where the optical characteristics of the recording layer have been changed. A typical example is a mode in which information is recorded by providing a signal area. Among such three-value or higher signal areas, there is no specific disclosure regarding the technology for creating areas with different optical characteristics of the recording layer when the recording layer is a single layer, and In the case of two layers, a method is disclosed in which the combination of materials of the upper and lower layers is changed depending on the difference in signal area.

The above method of providing a signal area of three or more values is effective for increasing the recording capacity of an optical disc, but it is an intermediate area [
There is a problem in that it is not easy to provide a region with changed optical characteristics. In other words, it cannot be said that it is easy to reliably change the optical properties inside the recording layer, such as crystallinity, through simple operations, and there are only a limited number of recording layer materials that have such properties. There is also the undesirable problem of adding unnecessary restrictions to the configuration of the recording medium. Furthermore, it is also possible to create multiple recording layers and create ternary or higher signal areas by combining (overlapping) the areas provided in each layer. In other words, the bit error rate tends to be very high in the recording methods of three or more values that have been proposed so far, and the current method is to record three or more values per dot. is difficult at a practical level.

Therefore, for example, it is extremely difficult to identify signal regions of three or more values in such a way that highly accurate identification is possible.

Another problem is that the storage durability of conventional optical discs as described above is only about 1 year, which is not sufficient.

Furthermore, since conventional optical discs record all information by converting it into digital signals, there is also the problem that it is difficult to record visible images, especially visible images with complex gradations. Of course, it is also possible to record such visible images using digital signals, but in that case there is a problem in that the recording capacity of conventional optical discs must be sacrificed significantly. In particular, when recording a color image on a conventional optical disc, it is necessary to further sacrifice the recording capacity. Therefore, this point also poses an obstacle for libraries to record literature books with photographs on optical discs.

On the other hand, information recording media have already been proposed in which digital signals are recorded by forming reflective areas and transmissive areas on silver halide thread black and white photographic materials, which have long been known as recording media for visible images. There is.

For example, a silver halide photosensitive material containing physical development nuclei in its surface layer is uniformly exposed to light, covered, and then developed.Then, the filament m is heated to 250 to 340°C in an aqueous solution to form a small, movable silver. The surface of the photosensitive material is made reflective by being broken down into particles and diffused onto the surface, and when writing is performed on this with a laser beam, the silver particles in the reflective film are diffused.
Regarding the type of recording material that is made transparent, Japanese Patent Laid-Open Nos. 55-108995 and 56-3
No. 3995, No. 56-49296, No. 56-
No. 3995, No. 57-46240, No. 58-
It is described in Publication No. 33243 and the like. The above-mentioned types of photosensitive materials have low sensitivity, require a strong laser light source, and have insufficient storage stability and recording density.

Also known is a recording material in which a continuous layer of black-and-white photosensitive emulsion is coated on a disc-shaped film base (Video Disc, by Efrem Siegel et al., supervised translation by Yoshiyuki Seki, ASCII Publishing, 1981. pp. 54-58). This recording material is used for binary recording, and after optical recording, development, fixing,
Although it can be washed with water, it has the drawback that the recording density is low because the size of one domain is 2 gm square or more, it is binary recording, and it is a single-sided transmission type.

[Object of the Invention] An object of the present invention is to provide an information recording medium that has improved storage stability and is capable of recording high-sensitivity, high-density information.

Another object of the present invention is to provide an information recording medium on which information can be easily written and read, has excellent storage properties, and enables high-density information recording.

Another object of the present invention is to provide an information recording medium that is capable of both high-density information recording using digital signals and analog recording of color images.

[Summary of the Invention] The present invention provides that information is recorded in a color photographic emulsion layer provided on the surface of a support by digital signals of two or more values set based on differences in color development per fixed area. The present invention provides an information recording medium characterized by the following.

In addition, the present invention records information and color images in the color photographic emulsion layer provided on the surface of the support using digital signals of two or more values set based on the difference in color development per fixed area. It also provides an information recording medium with the following characteristics.

[Detailed Description of the Invention] As described above, the information recording medium of the present invention has a color photographic emulsion layer provided on the surface of a support (preferably a disc-shaped support), which has a color emulsion layer that differs in color development per constant area. This is characterized in that information is recorded using digital signals of two or more values set based on the information.

That is, in the information recording medium of the present invention, a recording medium is prepared in which a color photographic emulsion layer is provided on the surface of a support, and the color photographic emulsion layer of this recording medium is divided in advance into minute regular arrays. By causing each minute area (pixel) to develop a distinguishable color at or above a preset value, the information to be recorded can be set based on the difference in the amount of color produced per fixed area. It can be manufactured by recording information using a digital signal that is greater than or equal to the octopus value.

The above information recording medium (unrecorded medium) can be produced by forming a color photographic emulsion layer on the surface of a transparent or light-reflective support (preferably a disk-shaped support). When a transparent support is used, information is read using transmitted light; when a light-reflective support is used, information is read using reflected light. Therefore, it is desirable that the light-reflective support itself has light-reflectivity or has a light-reflection layer on its surface.

As the support, for example, various synthetic resins used as supports for ordinary photographic films, or ceramics such as glass and chemically strengthened glass can be used as materials for the transparent support. In particular, synthetic resins such as polyesters such as polyethylene terephthalate, polyamides, epoxy resins, polycarbonate resins, acrylic resins, polyvinyl chloride resins, polyimides, and polysulfones have self-supporting properties and have excellent various properties. Preferably, a sheet is used as the support.

In addition, as a support having light reflective properties, a metal sheet,
Alternatively, a thin metal layer is deposited on the surface of a transparent or opaque sheet such as a synthetic resin sheet, glass plate, or ceramic sheet, or a white pigment such as titanium dioxide or barium sulfate or a highly reflective metal powder such as aluminum is dispersed. It is preferable to use a sheet made light-reflective by applying a suspension of a polymeric substance thereon.

A color photographic emulsion layer is provided on the support. This color photographic emulsion layer can be easily formed by applying a color photographic emulsion used in the preparation of ordinary color photographic film or photographic paper onto a support by a known method and drying it. can.

Ordinary photographic emulsions contain silver halide (AgX) as a light-sensitive component and also contain dye precursors (couplers) for forming color images. Photographic emulsions usually contain similar ingredients.

Any type of silver halide can be used, but for example, silver halide with a particularly small particle size (0.03~0.0
．． 2JLm) is desirable.

That is, in order to obtain high-density recording, which is the purpose of the IJ of the present invention, with a recording medium in which an AgX emulsion is coated as a continuous film on a transparent or light-reflective support.

It is necessary to prevent the incident light introduced into the color photographic emulsion layer from being scattered in the emulsion layer by, for example, silver halide grains existing near the surface. Therefore, it is preferable to use microscopic silver halide grains having a particle size in the range of 0.03 to 0.2 gm and a small light scattering cross section.

For this purpose, it is desirable to use silver iodobromide, which can easily form fine grains within the above-mentioned range in a stable manner and has excellent storage stability over time after production.

As the legal content of silver iodobromide, a range from 0 mol % to the solid solution limit can be used. In addition, when the legal content becomes high in silver iodobromide grains,
In the case of a color negative type, the development progress characteristics are poor, so it is preferable to use double-structure particles in which an AgBrI layer with a low iodine content (0 to 3 mol %) is laminated on the particle surface.

In order to obtain a high-density recording medium in which an AgX emulsion is coated as a continuous film on a transparent or light-reflecting support, it is necessary to reduce the amount of incident light introduced into the color photographic emulsion layer. It is necessary to reduce crosstalk between picture elements of incident light caused by light reaching the interface between the emulsion layer and the support and being reflected there. For this purpose, it is desirable that the incident light be absorbed by the emulsion layer as much as possible before reaching the interface between the emulsion layer and the support.
．． A large amount of sensitizing dye is added to small silver halide emulsion grains with a large specific surface area, such as those in the range of 2 gm, or small silver halide emulsion grains in the form of platelets. It is preferable to record with light.

This is because the silver halide grains have a large specific surface area and a large amount of sensitizing dye is added to them, and the absorption coefficient of the allowable transition of the sensitizing dye is greater than the intrinsic absorption coefficient due to the indirect transition of AgX. 0 When a sensitizing dye is added to the silver halide grains of the present invention, a large amount of the sensitizing dye is added to prevent light crosstalk between picture elements, but the range of the amount added is is preferable because the above effects can be particularly effectively obtained when used in an amount in the so-called desensitized region.As another form, the AgX emulsion layer has a two-layer structure, and the t
For the layer, an emulsion containing a sensitizing dye in an addition amount range that exhibits the highest sensitivity may be used, and for the lower layer, an emulsion containing a sensitizing dye in an addition amount e in a desensitized region may be used. In this case, the above effects can be obtained without significantly reducing the sensitivity of the recording medium of the present invention, and at the same time, the latitude of the recording medium can be improved.

Since these sensitizing dyes are alkaline decolorizing type, they are removed during development. Therefore, there is no problem when reading the recorded information.

As a method for forming AgX particles having a particle diameter of 0.03 to 0.2 m, the AgN0. It is formed by rush adding an aqueous solution and an aqueous halide aqueous solution over a short period of 4 minutes or less. This temperature constraint means that if you reduce the temperature further,
This is because the aqueous gelatin solution gels. However, low molecular weight gelatin (molecular weight 3000-100000) gelatin collected from fish living in cold seas (e.g. cod) and modified gelatin aqueous solutions such as phthalated gelatin, even at a concentration of about 2%, can be heated in the 35°C to 5°C range. Because it does not gel, AgX particles can be formed in this temperature range.
It is particularly preferred to form gX particles, and also for ordinary alkali-treated gelatin, the gelatin concentration is between 1.5 and 0.
In the 21% range, gelling (AgX particle formation) can be performed in the 35-5°C range. Therefore, using these conditions, the temperature is set at 35-5°C.

AgN0. Aqueous solution and alkali halide aqueous solution from 10 to
It is even more preferable to add with an addition time of 1 minute because finer particles of AgX can be stably produced.

Further, the emulsion of the present invention is preferably manufactured in a clean room used in the manufacture of VLSI semiconductors. This has the effect of reducing the inclusion of chips and reducing the bit error rate.

The silver halide contained in the color photographic emulsion layer of the recording medium of the present invention may be subjected to various chemical sensitization treatments.
In addition to silver halide, ordinary color photographic emulsions also contain binders such as gelatin or synthetic resins, couplers,
Dyes and various additives such as stabilizers, hardeners,
It contains a vehicle, an antistatic agent, a coating aid, a spectral sensitizer, etc., and the color photographic emulsion used to form the color photographic emulsion layer of undeveloped IJI can also naturally contain these additives. Regarding these, for example, Product, Licensing Index, Vol. 92, pp. 107-110 (
1971 12 B) and JP-A-58-113927
Publications and Research, Disclosure, Volume 176, 19
You can refer to the description in item 17843, December 1978.

In a normal AgX photographic film, the relationship between the exposure amount E and the optical density is as shown by the solid line in FIG. Since the number of particles exposed is reduced, the relationship between the exposure amount E and the optical density becomes as shown by a dotted line. This is because when using an emulsion consisting of large grains with high sensitivity and small grains with low sensitivity in order to widen the exposure latitude, the large grains are exposed and developed in the low exposure range. This shows that the density increases greatly each time a piece is developed. On the other hand, if a method of widening the exposure latitude is to use an emulsion with the same grain size but different sensitivity of individual grains, the relationship between the exposure amount E and the optical density is as shown in Section 10(b). This method is preferable because it has the advantage of being able to record more digital values as shown by the dotted line in the figure.

In the case of L, the method of obtaining an emulsion in which the two grain sizes are made the same and the individual grains have different sensitivities is as follows: (1) As mentioned above,
Using AgX emulsion grains with different amounts of adsorbed sensitizing dyes, (2
) Using AgX particles with different levels of chemical sensitization. (3
) Adding metal salts such as Rh, Ir, Cu, Hg, etc. to the interior or surface of the grains, (4) Using AgX emulsion grains with different amounts of emulsion stabilizer added, and (5), (1) to (4)
) is preferably used in various combinations.

As the color emulsion used in the present invention, it is preferable to use a color emulsion layer consisting of one or more colors, preferably two or more colors. For example, a blue photosensitive layer, a red photosensitive layer, a blue photosensitive layer, a green photosensitive layer, a red photosensitive layer. In this case, it is preferable to use an emulsion consisting of Ag Since the layer contains particles, it has blue sensitivity, so it is also effective to place a yellow filter that cuts blue light under the blue layer. As for these layer configurations, reference can be made to the lithographic color film and color paper R configurations. However, with ordinary color film and color paper systems, since they themselves darken the hard copy of the image, masking color correction using colored couplers and color correction using multilayer effects are required, but these methods are not fully completed. In the case of an IJI recording material, since it is read as an electrical signal, it can be corrected in the signal processing process, so it has the advantage that it is not necessary to incorporate all of them into the recording material. In addition, in the case of practical color film, blue,
The spectral sensitivities of the green and red layers overlap to some extent, and the spectral absorption spectra of the coloring dye also overlap to some extent. This is because if the overlap of each layer was completely eliminated, the film would not be sensitive at all when light corresponding to the wavelength of the valley was incident, but in the case of the recording material of the present invention, it is rather In fact, it is preferable that the spectral sensitivity spectra of each layer do not overlap, since later correction is not required. Therefore, it is also preferable to place a red filter that cuts green light under the green layer. The yellow filter disposed below may also be one that cuts out blue light more completely, and the wavelengths of the monochromatic light for exposure may be selected to avoid mutual overlapping exposure. Furthermore, when reading records, it is also possible to select monochromatic light having wavelengths that do not overlap with each other.

Further, regarding the coloring material used, although there are restrictions on color reproduction in ordinary color films, in the case of the recording material of the present invention, there are no such restrictions, so the coloring material can be selected more freely. Therefore, as the coloring material, a coloring material on the longer wavelength side may be used so that a semiconductor laser can be used during reading.

Regarding the photosensitive wavelength, you may use an emulsion with photosensitive characteristics on the longer wavelength side than ordinary color films. You can choose the color.

However, the basic principle that can be advantageously utilized in the present invention is as shown in FIG. Namely.

When blue light is incident, the blue photosensitive layer is exposed and develops its complementary color (yellow); when green light is incident, the green photosensitive layer is exposed and develops a magenta color; and when red light is incident, the red photosensitive layer is exposed to light and develops a cyan color. Note that the shaded peaks in FIG. 6 indicate that the coloring material absorbs light in that spectral region. On the other hand, peaks without diagonal lines indicate that the coloring material has no absorption in that spectral region. Therefore, when blue light is incident on the recording material recorded in this way and the transmitted or reflected light is observed, there is no interference with the signals recorded in the KK color layer or the red layer, and the blue light is observed. The blue color density of the layer can be read out. The same applies to the other layers, and signals can be read out independently from the three layers, the blue, green, and red layers.

2 This is the case with a normal negative color photosensitive material, but it may also have a coloring composition like a positive color photosensitive material. In normal color photographic materials, each of the blue, green, and red layers is composed of a 0 layer consisting of large particles and a 0 layer consisting of small particles in order to achieve high sensitivity. In the recording material of the present invention, in order to simplify the layer structure, each of the blue, green, and red layers may be provided with only one layer.

In a recording medium in which a plurality of continuous layers of photographic emulsion are coated on a transparent or light-reflecting support, each color photographic emulsion layer and support preferably have the following configuration.

Regarding the color photographic emulsion layer, it is preferable to reduce the layer thickness in order to reduce the spread of incident light in the emulsion layer. In this case, the layer thickness of the color photographic emulsion layer is 154 mm.
It is preferable that the number of layers is not more than m, particularly preferably not more than 8 layers m.

In addition, in order to prevent the spread of incident light in the color photographic emulsion layer due to the generation of reflected light from the surface of the support, an antihalation layer such as a colored resin layer or a gray silver layer is provided between the emulsion layer and the support. It is also preferable to provide a containing resin layer, etc. 0 As the coloring agent used for forming the colored resin layer, an alkali decolorizing dye and "Chemistry Handbook / Applications mJ (Japanese Chemical Complete Edition, Maruzen, 1980) Chapter 12, Television Society It is possible to use the dyes described in J.D., 1981, Vol. 3, p. 196. In addition, dyes and pigments can also be contained in the support.

Regarding the anti-halation layer, please refer to Research Disc'
O';Y+, l 76al December 978, Item 17643, XVI Section I can also be referred to.

On top of the color photographic emulsion layer is usually a transparent resin cover.
An i-layer is provided.

This is generally used for the purpose of protecting the AgX emulsion layer from chemical and physical external factors, but in the case of the present invention, bit errors may occur due to dust etc. adhering to the recording material. It also works to lower the probability. That is, when the incident light beam is focused onto the recording film, the overlying protective layer;

This is because the beam is spread out, so even if dust gets stuck there, the effect on the optical density is reduced. After recording and developing on this recording medium, a new transparent resin or glass substrate may be laminated on top of it to form a sandwich structure, or a cartridge structure may be formed to further reduce the bit error rate due to dust. .

Regarding these, reference may be made to the description in Nikkei Electronics, November 21, 1983, pp. 185-213.

FIGS. 1 and 2 are schematic diagrams showing the structure of the recording medium manufactured as described above.

FIG. 1 shows a recording medium consisting of a color photographic emulsion layer 12 and a protective J513 formed on a transparent support 11,
FIG. 2 shows a support 21 on which a reflective layer 24 is formed;
Each color photographic emulsion layer representing a recording medium consisting of a color photographic emulsion layer 12 and a protective layer 13 formed thereon has a yellow dye layer (
Y), magenta dye layer CM) and cyan dye layer (C)
are sequentially planted, and a yellow filter layer (YF) is placed between the yellow dye layer (Y) and the magenta dye layer (M).
) is provided. However, it is not necessary to use all three colors listed above, and a combination of only any two colors may be used.

The dotted lines inserted to divide the color photographic emulsion layers in each figure indicate picture element units, and the division between these dotted lines constitutes one picture element. In this case, it is necessary to place alignment marks at two or more locations on the recording medium.

Note that the picture elements may be virtually partitioned as shown in FIGS. 1 and 2, but as shown in FIG. 3, the light 'i! ! It may be separated by a shield or a barrier made of a light-reflecting material.

That is, FIG. 3 shows a recording medium consisting of a color photographic emulsion layer 32 and a protective layer 33 formed on a transparent support 31, but this color photographic emulsion layer 32 is a barrier made of a light-shielding or light-reflecting material. It is divided by 35. By dividing the picture elements with light-shielding or light-reflecting materials in this way, an optical barrier is created between each picture element, which greatly reduces the occurrence of crosstalk between picture elements when recording (writing) and reading digital information. It can be F,
It also makes tracking easier.

Compared to the conventional thermal change method of picture elements by laser beam irradiation, in this case, the light blocking limit between picture elements determines the recording density, so for example, for aluminum metal, the theoretical limit is about 0.06 lumen thickness. Therefore, theoretically, the number of cells can be increased from several times to several tens of times compared to conventional optical discs.

Also, compared to a case where AgX emulsion was coated as a continuous film on a support.

(1) There is no crosstalk between picture elements due to light scattering of AgX particles. (2) There is no crosstalk between picture elements due to light reflected at the boundary between the emulsion layer and the support layer. (3) There is no crosstalk between picture elements due to light scattering of the support layer. (4) In the continuous film type, in order to reduce the crosstalk caused by (1) above, there is no crosstalk between picture elements due to light reflected at the lower support/air layer interface. Although it is necessary to reduce the thickness, this is no longer necessary, and the AgX emulsion layer can be made thicker, resulting in the advantage that the optical density can be increased to a higher level.

Another form fKi of the present invention may not only be a form in which the AgX emulsion is completely accommodated only in microcells, but also a form jE in which a part is a continuous film.For example, an example thereof is shown in FIG. show. That is, a barrier 95 is formed on a transparent substrate 91, an AgX emulsion layer 92 and a retention Is layer 93 are formed thereon, and exposure is performed from the AgX emulsion layer side to perform recording and reading of information. Therefore, in these cases, the above-mentioned restrictions on the AgX emulsion are eliminated, which is particularly preferable, and the factor that hinders high density in this case is not the above-mentioned factors, but the fine processing precision of microcell formation. However, in order to put AgX emulsion particles into the microcells,
It is necessary to micronize the AgX particles. In order to form picture elements into microcells using a light-shielding or light-reflecting material, for example, US Pat. No. 4,375,507, q.
Shikai No. 59-202100, European Patent No. 5856
No. 8 and Specification of Japanese Patent Application No. 176393/1983, No. 60
The method described in Japanese Patent No. 176394 can be used.

However, among these, oxygen plasma RI is preferred in terms of fine processing accuracy and ability to control the shape of microcells.
The method of forming microcells using method E is superior. The following method is particularly good. A metal film (
For example, an AfL deposited film) is formed, a light-absorbing or light-reflecting micro-wall material (for example, a dyed gelatin layer or a gelatin layer with TiO2 dispersed therein) is applied to the north of it, and A! ; After depositing L and buttering etching the deposited film of A pattern by photolithographic etching process, using this deposited An film as a mask, 0□+CF,
(10-2 to 20 mol %) plasma is used for RIE etching. In this case, the organic coating layer is etched away by oxygen RIE, but since the Al alumina layer is formed and is not etched, there is an advantage that the depth of the microcells can be made uniform.

Regarding such fine loading and RIE, see Conductor Research 1
4 “Very LSI technology microfabrication”, edited by the Semiconductor Research Promotion Association (published by the Industrial Research Association), “Semiconductor plasma process technology”,
Edited by Takuo Kanno, 1980 edition (Sangyo Tosho) and 5olid
5tate Technology (woodblock print), 19
March 1985 issue, p. 66-75! Plasma chemistry in the flLsI era, edited by the "Electronic Materials" editorial department (published by Kogyo Kenkyukai)
, 1983, can be referred to.

Another method for forming microcells is to add a hardening agent to an aqueous gelatin solution, apply it onto a substrate, and emboss it (
It is also suitable to perform pressing processing using a mold whose surface has been formed with irregularities in advance, and then to remove the mold after the dura mater reaction has proceeded optimally.

In addition, a photosensitive colloid liquid on a support (for example, Dic
After applying chromate gelatine and exposing the pattern to an array shape of openings using electromagnetic waves such as ultraviolet rays, etching may be performed into a microcell shape by immersing it in an appropriate etching solution, or it may be etched into a positive or negative type. A pattern of photoresist may be formed on the support, exposed to light in a pattern, and then etched.

It is particularly preferable to use a water-swellable polymeric material such as gelatin as the wall material of the microcell. It is the thickness of the silver halide emulsion coating film.

This is about 20 times as large during coating and development as when drying, so if the microcell wall material is a solid that does not swell in water, the AgX emulsion layer will jump out of the microcells during pattern development, for example.

When a water-swellable material is used, such troubles do not occur because the microcell wall material is also moved to the U side during development.

Also, during coating, if the microcell wall material is a solid that does not swell on wood, even if the AgX emulsion is accommodated in the microcell in a favorable state during emulsion coating, the AgX emulsion will be filled only at the bottom of the microcell during drying. This results in a similar shape, and the filling of the AgX emulsion into the microcells is not successful.

However, if the microcell wall material is water-swellable, even if m layers of AgX emulsion are formed on the top of the microcell during coating, the microcell wall material will swell and the AgX emulsion will be incorporated into the microcell. , the depth of the microcells increases, so that the AgX emulsion is preferably accommodated in the deep microcells. This method also solves the problem that it was difficult to pack AgX emulsion into microcells without leaving almost any air space.

At this time, the upper layer is made of an emulsion with a high moisture content, and the upper layer is a normal A
It is also possible to apply a gX emulsion.

In addition to gelatin, the water-swellable polymeric material is also preferably polyimide, which is used as an insulating photoresist material from the viewpoint of water absorption and microprocessability.

Other Chemical Handbook, Applied Edition, Chapter 10 “Polymer Chemical Industry”
1 Edited by the Chemical Society of Japan, 1980 (roundness), Research, Disclosure Volume 176, December 1978,
Item 17643. Reference may be made to the AgX binder described in Section IX.

In addition, by passing it through an ultrasonic defoaming device immediately after application,
It is also effective to dissolve or remove residual air in the microcells into the emulsion. This coating may be carried out on a long sheet and then cut into discs, or it may be spin-coded onto a disc-shaped substrate from the beginning.

In the information recording medium of the present invention, when the support is light reflective, color photographic emulsion layers can be provided on both sides of the support. An example of such an embodiment is shown in FIG. 4, which shows a support 41 with reflective layers 44 and 48 formed on both sides of the surface, and a color photographic emulsion layer 42 (color photographic The emulsion layer is separated by a barrier 45 made of a light-shielding or light-reflecting material) and a protective layer 43
A recording medium consisting of

A method of making the side walls of the microcell light-absorbing is to use a polymeric material colored with a dye or a polymeric material mixed with a pigment as the corner wall material of the microcell. These are coated on a transparent or light-reflective support and processed to form microcells.

For information on these dyes and pigments, please refer to the "Chemical Handbook, Applied Edition"
, edited by the Chemical Society of Japan, Maru Bt 9ao, Teppe Doya Shin-edan Gakusenko Handran, 9 Yu 41 Synthesis” 1 δ-kai ed. 9 Bonzen (1970)
can be used as a reference. In particular, a light-absorbing layer in which carbon black is kneaded is excellent in that it has antistatic properties, does not fog the emulsion, and has good RIE processability.

Information is recorded on the color photographic emulsion layer of the recording medium produced as described above using digital signals of two or more values set based on the difference in color development per fixed area printing.

The recording (writing) of the digital signal described above is achieved by first irradiating the color photographic emulsion layer with light to cause the development of one type of color or more colors preset for each pixel of the color photographic emulsion layer. can be done. Recording of digital signals by this light irradiation can be performed using, for example, monochromatic light.

This reading operation can be carried out by irradiating light from either the support side or the surface side of the color photographic emulsion layer when the support is transparent, or by irradiating the color photographic emulsion layer when the support is opaque. This can be carried out by irradiating light from the layer surface side.

Further, as shown in FIG. 4, when color photographic emulsion layers are provided on both sides of the support, writing is performed by irradiating each color photographic emulsion layer with light from its surface side.

For example, when using silver halide grains with a grain size of 0.24 m or less, the light scattering is mainly based on Rayleigh scattering.
It is preferable to use light with a wavelength of nm or more, which is
This is because by using light of such a wavelength, light scattering in the color photographic emulsion layer can be reduced. However, in a microcell system as shown in Figure 3, even if there is light scattering, crosstalk is not a problem.
Not subject to this restriction.

By the above exposure, for example, mutually distinguishable colors as described below can be generated in each picture element.

For each picture element, one of the three colors (or two of them) used in the subtractive color method is developed and digitally recorded. In this case, by combining the type of color development and the level of color development (color density), it is possible to record two to several types of distinguishable digital signals.

For each picture element, the above-mentioned three primary colors (or two of them may be used) used in the subtractive color method are combined to develop a color and are digitally recorded. Even in this case, by combining the type of color development, the combination of dyes, and the level of color development (color density), it is possible to record two to several f' types of distinguishable digital signals.

In this case, the method of combining the type of color development, the combination of dyes, and the level of color development (color density) will give the highest recording density, so it is preferable 0. For example, if we compare the recording density for two picture elements, the blue layer In the case where the green layer records the C value, the green layer records the b value, and the red layer records the C value, in the above method, (a
+b+c) This is a binary record, but when the blue, green, and red layers are made into independent digital records, (a'+b'+
c 2) Record the value (a+b+c)'n(a'+
b 2+02).

The reproduction of the information recording medium of the present invention is, for example, a mother of -! (
After manufacturing the mother disk, subsequent photo duplication (printing) techniques such as negative/positive contact duplication (printing), positive/positive contact duplication (printing), etc., are used to perform high-precision and easy copying. I can do it. That is, there is no need for the troublesome operation of scanning the disk with a laser beam and copying it, and there is a rapid processing capability in that copying can be done by contact exposure using a flash of monochromatic light.

Reading information from the information recording medium according to the present invention formed as described above can be performed as follows.

For information recording media that use a transparent support, each pixel is continuously irradiated with light that is focused into a spot from either the support side or the surface side of the color photographic emulsion layer, and the intensity of the transmitted light is detected. By doing this, the color development in each picture element is detected, and by photoelectrically converting this, recorded information can be read out by assigning each designated digital signal corresponding to the detected color development.

In information recording media using a support with a reflective layer, each pixel is irradiated with light converged into a spot from the surface side of the color photographic emulsion layer, either continuously or in a flash, and the reflected light is detected. By similarly detecting color development in each picture element and photoelectrically converting this, recorded information can be read by assigning a designated digital signal corresponding to the detected color development. In addition, to read the color level of three or more values, the transmitted or reflected light is detected with a photodetector such as a photodiode, which is input to the comparator of the A-D converter. Can be read as output.

The effective recording area of the transmissive type is half that of the reflective type, but since it does not pick up surface reflected light, the maximum optical density (D
The transmissive type has the advantage that the transmission type can have a larger value of mat), and the blackening density level per picture element can be increased. Also, if information is recorded in color,
It also has the advantage that the influence of the sub-absorption spectrum of the dye can be reduced compared to the reflective type. [(Journal of the Photographic Society of Japan,
48, p. 274 (1985)].

On the other hand, in the case of the reflective type, the effective recording area is twice as large as that of the transmissive type, but it also has the disadvantage that the D-fix cannot be made large because it picks up the light reflected from one surface. To deal with this, as illustrated in FIGS. 7(a) and 7(b), if the protective layer or surface layer (73) and the reflective layer (74) of the microcell are made non-parallel, , this disadvantage is alleviated. For example, as shown in Fig. 7(a),
If the amount of coated emulsion is slightly less than the amount that fills the microcell, it can be easily made due to its drying properties, or as shown in FIG. It can also be easily made by tilting the .

In addition, in the case of color, the blue, green, and red lights are shown in Figure 11 as shown in Figure 11. At the same time, a reading method using the configuration shown in Fig. 11 can be considered, but as shown in Fig. 12, light sources are arranged in parallel to expose and record.
When reading records, it is easier to use the configuration shown in FIG. 12. In this case, the blue, blue, and red signals are not recorded in the same pixel, but when reading out the recording, the first
Since these signals are read out using the configuration shown in FIG. 2, they are read out at the same time, which is equivalent to being recorded in a pixel. In this case, the intervals between the eight colors, green and red lights can be arbitrarily selected.

Furthermore, when natural light is used when reading data into or reading from the recording medium of the present invention, a light source as shown in FIG. 8 can also be used. That is, between the monochromatic filter 82 and the lens 83 in front of the light source lamp 81, various contact masks 84, for example, a chrome mask (having pinholes) used in the semiconductor VLSI manufacturing process, are placed. The image is formed on the recording medium 85 of the present invention. This case has the advantage that a minute spot can be created using a simple optical system. As this monochromatic light source, bright lines such as Hg and Xe can also be used.

The information recording medium of the present invention has a color photographic emulsion layer provided on a support (preferably a disc-shaped support) as a main component, and is usually disc-shaped as a whole.
takes the form of The information recording medium for the unreleased January record is digitally recorded using a recording medium (color photographic emulsion) that was conventionally used to record analog information as a color photographic image. Another useful embodiment of the information recording medium is an embodiment in which not only information based on digital signals as described above but also visible images are recorded in the color photographic emulsion layer. FIG. 5 shows an example of the recording position of this visible image.

FIG. 5 shows a fourth embodiment of the disc-shaped information recording medium of the present invention.
This is a one-page view, and the peripheral area is a digital signal recording area 5.
It is said to be 1. Then, an area inside the area that is not suitable for digital signal recording is defined as a color image recording area 52. That is, by adopting such an arrangement, the entire surface area of the disk-shaped information recording medium is effectively used for information recording, and this also realizes an increase in the overall recording capacity.

As shown in L, information based on digital signals and visible images -
- When recording on a single sheet of information recording medium, for example, information regarding visible images (
It is desirable to record signals such as a signal notifying the attachment of a color image, a signal notifying the location and type of the color image, etc.

Note that color images may be recorded as time-series analog signals along a track. In other words, the recording medium of the present invention has a format in which digital recording and time-series analog signals coexist on one disk. Very good.

[Effect of the invention] Since the information recording medium of Unreleased II is based on the conventionally known photographic technology using photosensitive silver salt, it can be manufactured with high precision and easily, and it can be recorded easily. It is also possible to read out digital signals with high precision.

Furthermore, the high storage stability and high sensitivity of silver halide photographic images are already known, and the information recording medium of the present invention is an optical disc that utilizes the physical deformation or physical property change of the currently used recording layer. High storage stability and high sensitivity are guaranteed compared to Therefore, the information recording medium of the present invention is particularly suitable for recording legal documents that require long-term storage.

Furthermore, a compact light source can be used without requiring a high-intensity light source.

Furthermore, since the information recording media of the unreleased 11 utilize a method that records digital signals by dividing them into three levels, they are significantly more effective than digital signal recording media that use conventional photographic technology. This results in a significant increase in recording capacity. Reproduction can also be done quickly and easily.

In addition, since the information recording medium of the present invention can record not only digital signals but also color images, it is possible to record the content of documents such as calligraphy foil, magazines, or literature in which color photographic images are written at the same time as text. Particularly suitable for record keeping.

[Brief explanation of drawings]

FIGS. 1 to 4 are schematic diagrams each showing the structure of a recording body used in manufacturing the information recording medium of the present invention. Note that the configuration of the information recording medium of the present invention is also shown by these schematic diagrams. FIG. 5 is a diagram showing an example of an information recording medium according to the present invention in which both digital signals and color images are recorded. FIG. 6 is a diagram schematically showing a coloring system that can be advantageously used in an information recording medium with undeveloped IJl. Both FIG. 7(a) and FIG. 7(b) are diagrams showing examples of the state of the recording layer of the information recording medium of the present invention. FIG. 8 is a configuration diagram showing an example of a light source and an optical system that can be used when inserting into and reading information from an information recording medium according to the present invention. FIG. 9 is a diagram showing another example of the configuration of the information recording medium of the present invention. Figure 10(a) and Figure 1o(b) both show the exposure amount (E) and optical density (D) in a conventional silver halide photographic film system.
) (solid line) and the relationship (dotted line) between exposure amount (E) and optical density (D) in the information recording medium system of the present invention. Both FIG. 11 and FIG. 12 are diagrams schematically showing a method that can be used for recording on an information recording medium and reading recorded information according to the present invention. 11.21.31.41.91: Disc-shaped substrate 12.22
．． 32.42.92: Color photographic emulsion layer 13.23.33.43.73.93: Protective layer 24.4
4, 74: Reflective layer 35. 45. 95: Light shielding or barrier made of light reflective material 51: Digital signal recording area. 52: Color image recording area 81: Light source lamp 82: Monochromatic filter 83: Lens 84: Contact mask 85: Information recording medium patent applicant Fuji Photo Film Co., Ltd. Representative Patent attorney Yasushi Yanagawa Figure 1 Figure 2 M3 Fig. 4 Fig. 5 Fig. 6 Fig. 6 Tomazenta) Buy ＼-n-Two zelkova colored layers □ 1 skin length Fig. 11 Blue, Zhang Red Fig. 7(q) Fig. 7(b) Fig. 8 figure

Claims (1)

[Claims] 1. Information is recorded on a silver salt color photographic emulsion layer provided on the surface of a support using digital signals of two or more values set based on differences in color development per fixed area. An information recording medium characterized by: 2. Claim 1, wherein the digital signal of two or more values is made of any one kind of dye selected from the group consisting of yellow dye, magenta dye, and cyan dye, or a combination of a plurality of dyes. Information recording medium described in section. 3. The information recording medium according to claim 1 or 2, wherein the support is a disk-shaped support. 4. The information recording medium according to claim 1 or 2, wherein the support is a transparent support. 5. The information recording medium according to claim 1 or 2, wherein the support is a light reflective support. 6. Information and color images are recorded on the silver salt color photographic emulsion layer provided on the surface of the support by digital signals of two or more values set based on the difference in color development per fixed area. Information recording medium. 7. Claim 6, characterized in that the digital signal of two or more values is made of any one kind of dye selected from the group consisting of yellow dye, magenta dye, and cyan dye, or a combination of a plurality of dyes. Information recording medium described in section. 8. Claim 6, characterized in that the information about the color image is recorded as a digital signal.
Information recording medium described in section. 9. The information recording medium according to any one of claims 6 to 8, wherein the support is a disk-shaped support. 10. The information recording medium according to any one of claims 6 to 8, wherein the support is a transparent support. 11. The information recording medium according to any one of claims 6 to 8, wherein the support is a light reflective support.