JPS6392946A - Recording medium and color image forming method using the same - Google Patents

Abstract

PURPOSE:To form a color image by selecting the combination a photosensitive wave length of a photosensitive chromoprotein and a color displaied by a coloring means. CONSTITUTION:The recording layer 2 is formed in such way that mosaic like image forming units 2a composed of a coloring layer 2aa constituting the coloring means and a photosensitive layer 2ab supporting the photosensitive chromoprotein are adjacent to each other. Said layer 2 is mounted on the substrate 1. The elements of the unit 2a are combined in such way that the photosensitive wavelength of the layer 2ab is different when the color displaied by the layer 2aa is different. The layer 2aa contains a substance capable of coloring by change of a hydrogen ion concn., for example, such as pH indicator in a gel. The layer 2ab contains a photosensitive chromoprotein preferably a bacteriorhodopsin or its derivative in a gel, followed by laminating it on the layer 2aa. Thus, the full colored image is formed, when the units 2a are constituted of >=3 kinds combination including three primary colors.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a recording medium that utilizes the function of a photosensitive pigment protein and a recording method using the same.

(Prior art) Silver halide (silver salt) is a method for forming color images.
The most common method is known as the silver salt color photographic process, which combines sensitizing dyes, photocoupler dyes, etc. Is this process 13.4 a method to obtain high-sensitivity, high-resolution, and high-definition images?The exposure, development, and fixing processes are complicated, and expensive silver is used, so it is difficult to reduce costs to some extent. There is a limit.

On the other hand, the electrophotographic process using the so-called electrostatic recording method has advantages such as a simpler process and lower running costs compared to the silver halide color photographic process, but it is difficult to produce color and has high-definition It is difficult to obtain a good image,
It also has drawbacks such as difficulty in expressing halftones.

In contrast to these methods, an image forming method using rhodopsin, which utilizes reactions in living organisms, is disclosed in U.S. Pat. No. 4,084,96 by D.F.
7 and 4,356,256.

[Problem that the invention seeks to solve]

As mentioned above, the F, 0° Br1en image forming method utilizes the function of rhodopsin, which is a substance that exists in the retina of living organisms and is involved in light sensing with extremely high sensitivity and high resolution in living organisms. Although this method has effects such as high amplification, high sensitivity, and high resolution, its application is limited to the formation of monochrome images, and the formation of color images has not been demonstrated at all.

Therefore, the present inventors have completed the present invention as a result of intensive studies to utilize the characteristics of photosensitive pigment proteins including rhodopsin in forming color images.

An object of the present invention is to provide a recording medium for forming a color image using a photosensitive pigment protein and a method for forming a color image using the same.

[Means for solving problems]

That is, the present invention provides a region that retains a photosensitive pigment protein and:
A combination of an image forming unit having a coloring means that develops color according to a change in hydrogen ion concentration in a line region, and an image forming unit in which the coloring means exhibits different colors and the photosensitive pigment protein has a different sensitivity wavelength for each different color. A recording medium characterized by having a recording layer in which one or more pairs of are mixed together, and a region that retains a photosensitive pigment protein and water: a region that develops color according to changes in hydrogen ion concentration in a line region. A record in which image-forming units having a color-forming means and: are mixed in such a way that there is one or more combinations of image-forming units in which the color-forming means exhibit different colors and the photosensitive pigment proteins have different photosensitive wavelengths for each different color. A method for forming a color image, comprising a step of irradiating a recording medium having a layer with light having a wavelength corresponding to a color exhibited by an image forming unit according to image information.

A typical example of the photosensitive pigment protein used in the present invention is visual substance, which consists of opsin (protein part) and retinal (
It is a substance that is involved in the photosensitivity function of living things, consisting of a chromophore), which receives light and converts it into some kind of chemical change, thereby producing light sensation and other functions. 6 The bacteriorhodopsin used in the present invention has a chromophore similar to the visual substance and has a similar function. The ability to do so (proton pump ability) is utilized. Therefore, as the photosensitive pigment protein used in the present invention, various photosensitive pigment proteins can be used as long as it has such a function, and the photosensitive pigment protein is not limited to the type. Examples include visual substances such as rhodopsin, polyphyllopsin, iodopsin, and the like.

As the photosensitive pigment protein used in the present invention, for example, those extracted and purified from cells of the photosensitive area of living organisms such as the photoreceptor segments of the retina of animals that have various types of photosensing, and from photosensitive microorganisms can be used. Among them, bacteriorhodopsin [W, 5toeckenius, R, A,
Boqomolni, Ann, Rev.

Biochem, 52.587~-616 (198
2)], for example, D, Qesterh
elt, W, 5toeckenius [Method
in Enzymoloc+y, 31,667-6
78 (1974)], and is convenient because it is easily available.

From these photosensitive pigment proteins, there are two types with different photosensitive wavelengths.
The above may be selected and used depending on the desired configuration of the recording medium.

Further, the structure of a natural photosensitive pigment protein isolated from a living body can be changed without impairing its function to form a derivative with a changed photosensitive wavelength, which can be used in the present invention.

Typically, the retinal portion can be changed to change the wavelength of light at which it is sensitive. To give a specific example of the formation of such a derivative in rhodopsin, for example, bacteriorhodopsin with a maximum absorption wavelength of 570 nm by changing the retinal moiety to a) all-trans-retinal [
P,Townor,W,Gaerther,et,al.
, ,Eur, J.

8iochem, 117.353-359 (19
81)], b) bacteriorhodopsin with a maximum absorption wavelength of 550 nm by using 13-cis-retinal [same as above, c) bacteriorhodopsin with a maximum absorption wavelength of 18475 nm by using 5,6-dihydroretinal [ R, Mao, R, Govindjee, et al.
, Biochemistry.

Kasa, 428-435 (1981) ], d) Retro-γ
- By using retinal, the absorption maximum wavelength can be increased to 430
Bacteriorhodopsin as nm [Ni, S, Huang
c+,H,8aylay,et,al,,Fed,
Proc.

ρ, +659 (+981) ko, e) By using 3.4-dihydroretinal, the maximum absorption wavelength was increased to 5
Bacteriorhodopsin [F, Tokun
a9a, T, Ebrey, Biochemistry,
17°1915~+922(+978) etc.

Furthermore, the amino acid sequence of bacteriorhodopsin has already been revealed [Yu, A., Ovchinnikov
.

N., G., Abdulaev, et. al., B.
1oor9. Him, 4, 1573-+574 (
1978)], and the base sequence of the bacteriorhodopsin gene is also R1, Dunn, J.M., McCo.
y etc. [Proc, Natl, Acad, Sci,...
78.6744-6748 (1981)].

Therefore, by manipulating the base sequence of the bacteriorhodopsin gene, we can create bacteriorhodopsin genes with different absorption wavelengths and create recombinant DNA using them! Configure
Bacteriorhodopsin produced in a host by cloning can also be used in the present invention.

The coloring means in the present invention consists of a substance or a reaction system that develops color in response to changes in hydrogen ion concentration in the region containing the photosensitive pigment protein caused by hydrogen ions transported by the photosensitive pigment protein that has received light, such as a) A substance comprising a substance that develops a desired color according to a change in hydrogen ion degree J in the region containing the photosensitive pigment protein or in a region in contact with the region, b) Desired color. An enzyme whose optimum pH range is specified to be involved in the coloring reaction and a substance necessary for the coloring reaction are contained in the region containing the photosensitive pigment protein or in the region in contact with the region. In addition, structures that utilize various methods that can visualize changes in hydrogen ion concentration and electrochemical potential can be used in the present invention.

Examples of the above a) include so-called pH indicators such as cresol purple, bromothymol blue, neutral red, phenol red, cresol red, and α-naphtholphthalein, which are used together with water.

In order to form a region holding a photosensitive pigment protein, various immobilization methods can be used, such as immobilization in a gel, immobilization using a binder, immobilization by microencapsulation, etc., and the materials used include: For example, collagen, polyacrylamide, cellulose, porous glass, etc. can be used.

In order to obtain the action of the photosensitive pigment protein, it is necessary to further retain water in the area holding the photosensitive pigment protein, but it is necessary to retain water during the formation of the area holding the photosensitive pigment protein, or for example in the recording medium after formation. It can be contained in the region during use.

Further, even when the coloring means is formed independently of the region holding the photosensitive pigment protein, the above-described immobilization method can be used.

Hereinafter, the structure of the recording medium of the present invention and the image forming method using the same will be explained in detail with reference to the drawings.

FIG. 1(A) is a schematic plan view of a configuration example of a recording medium of the present invention, and FIG. 1(CB) is a schematic cross-sectional view taken along line AA in FIG. 1(A).

In the recording medium of this example, a mosaic-like image forming unit 2a consisting of two layers, a coloring layer 2aa constituting a coloring means in the present invention and a photosensitive layer 2ab holding a photosensitive dye protein, is arranged on a base material 1 at a distance of 11g1 from each other. Recording layer 2 mixed in contact with each other
is configured.

Here, each image forming unit 2a is mixed in the recording layer so that there is one or more combinations of image forming units whose color-forming layers exhibit different colors and whose photosensitive dye proteins have different photosensitive wavelengths for each different color. ing.

The color-forming layer 2aa is formed by incorporating, for example, the above-mentioned gel into the above-mentioned substance or reaction system that develops color according to a change in the hydrogen ion concentration, such as a pH indicator, and is provided on the base material in a predetermined pattern.

The photosensitive layer 2ab is, for example, a gel containing a photosensitive dye protein and further provided on the recording layer 2aa in a pattern corresponding thereto.

Note that the fi types of image forming units, the number of colors they exhibit, or their shapes and sizes may be selected as appropriate depending on the use of the recording medium.For example, two types of image forming units exhibiting different colors may be mixed. If used in combination, it is possible to express colors in four ways (including the case of no coloration), and if image forming units exhibiting three different colors are used together, it is possible to express colors in 8 ways (in the case of no coloration). ) is possible. Furthermore, for example, day (red), G (green), B (blue)
A full-color image can be obtained by using three or more types of primary colors, including a combination of the three primary colors, Y (yellow), M (magenta), and C (cyan).

On the other hand, the relationship between the photosensitive wavelength of the photosensitive pigment protein in one image forming unit and the color exhibited by the coloring layer can be determined by, for example, a) combining a photosensitive pigment protein that is sensitive to red light and a coloring layer that exhibits red color. If the photosensitive wavelength characteristics of the photosensitive pigment protein and the coloring characteristics of the color exhibited by the coloring layer are made to correspond directly, coloring with wavelength characteristics corresponding to the wavelength characteristics of light can be directly obtained in the image forming unit, resulting in a positive color image. b) By combining a photosensitive pigment protein that is sensitive to red light and a coloring layer that exhibits cyan, the sensitivity wavelength characteristics of the photosensitive pigment protein and the coloring characteristics of the color exhibited by the coloring layer are complementary colors. If the colors are made to correspond in a complementary color relationship to the wavelength characteristics of light, colors with wavelength characteristics corresponding to the wavelength characteristics of light in a complementary color relationship can be obtained for each image forming unit, and a negative color image can be obtained.

However, even if the photosensitive wavelength of the photosensitive pigment protein does not directly correspond to the color exhibited by the color-forming layer, the photosensitive wavelength of the photosensitive pigment protein included in the image forming unit can be used to record image information. If selectively irradiated according to the following, that is, if selectively irradiated with light that includes the photosensitive wavelength of the photosensitive pigment protein contained in the image forming unit to be colored, it is possible to form a color image corresponding to the recorded image information. .

In addition, each component when forming the image forming unit 2a is contained at a concentration such that a change in hydrogen ion concentration can be obtained to a sufficient extent to obtain coloring by the coloring means, and each reaction can proceed satisfactorily. Just let it happen.

Furthermore, in order to obtain a change in hydrogen ion concentration with the photosensitive pigment protein, it is necessary to have sufficient moisture present6.For example, in the case of immobilization with a gel, the moisture content should be at least 15% or more. Preferably, it needs to be 25% or more.

In addition, the desired area containing the photosensitive pigment protein and the area constituting the coloring means should be prepared with appropriate physical, chemical, or biochemical environmental factors such as pH 1 osmotic pressure so that these areas can function adequately. It goes without saying that you should leave it there.

The base material 1 is made of resin such as triacetate or polyester,
It can be formed from glass, ceramics, metal, paper, etc. as desired.

In the above example shown in FIG. 1, the photosensitive layer and the coloring layer are separated into two layers, but the recording medium of the present invention is not limited to such a configuration, and these layers are in the same layer. The recording layer may have a structure in which the photosensitive layer and the recording layer are stacked in a desired order.

Next, a method for forming a color image using a recording medium having such a configuration will be described with reference to the drawings.

Figure 2 is a schematic cross-sectional portion of an example of a recording medium in which the recording layer is formed by matching the photosensitive wavelength characteristics of the photosensitive pigment protein and the coloring characteristics of the coloring layer in one image forming unit in the configuration shown in Figure 1 of Section 1. be. Therefore, in this case, a positive image is obtained.

In this example, the colored layer 2a of the image forming unit 2a-1
The color exhibited by -1-a is R (red), and the photosensitive layer 2a
-1-b retains a red-sensitive photochromic protein. Hereinafter, colored layer 2a-2 of image forming unit 2a-2
-at, ltG (green), and its photosensitive layer 2a
-2-b retains a green photosensitive pigment protein,
Further, the colored layers 2a-3-al, t of the image forming unit 2a-3
B (blue), and a blue-sensitive photosensitive pigment protein is retained in the photosensitive layer 2a-3-b.

In order to form an image using this recording medium, first,
If the recording layer does not contain sufficient moisture in advance, the recording layer is moistened with water to replenish the moisture.

Next, the recording layer is irradiated with light according to the image information.

For this light irradiation, for example, a desired translucent positive color original image is superimposed on the recording layer, and white light is irradiated from above.
Alternatively, it is possible to apply a method of sequentially irradiating red, green, and blue light while selecting the irradiation area depending on the information separated into the three primary colors of the desired color image 1R1G and B.

Then, in each photosensitive layer, the photosensitive pigment protein is exposed to light depending on the wavelength characteristics of the light irradiated to each part, and hydrogen ions are released there, and the hydrogen ion concentration changes. Then, the coloring layer develops color due to the change in hydrogen ion concentration.

That is, for example, in a part illuminated only with red light,
Only the image forming unit 2a-1 develops color and is expressed in red. Hereinafter, parts irradiated with green (or blue) light will be expressed in green (or blue). Further, in the portions irradiated with yellow light, that is, light having wavelength characteristics of both red light and green light, image forming units 2a-1 and 28-
2 develops color and is expressed in yellow. Below, R, G,
A full-color image is formed by a combination of the three primary colors of B.

On the other hand, FIG. 3 shows an example of the recording medium of the present invention in which there is no direct relationship between the photosensitive wavelength characteristics of the photosensitive pigment protein and the wavelength characteristics of the color of the coloring layer, as in the example shown in FIG.

In other words, 3f! The colors exhibited by the image forming units are the same as those in the example shown in FIG.
It is.

In the case of this optical recording medium, FIGS. 4(A) to 4(C)
As shown in ), for example, light having wavelengths of λ1, λ7, and λ3 is sequentially irradiated according to the information separated into the three primary colors of color image %R, G, and B. That is, exposure with light of λ1 is selectively performed based on information regarding the day, and hereinafter, light with a wavelength of λ2 is selectively irradiated on G and light with a wavelength of λ3 is selectively irradiated on the basis of information regarding B. be done.

Thereafter, through the same coloring process as explained in FIG. 1, a color image consisting of a mosaic of three colors as shown in FIG. 4(C) (coloring portions are indicated by letters of the alphabet) is formed.

[Effects of the Invention] According to the present invention, it has become possible to form color images with high sensitivity and optical resolution, which was previously impossible, by effectively utilizing the characteristics of photosensitive pigment proteins.

Furthermore, in the recording medium of the present invention, by selecting the combination of the photosensitive wavelength of the photosensitive pigment protein and the color exhibited by the coloring means, a full-color image can be produced by a simple exposure method using a translucent positive color original image. It can be easily formed directly.

〔Example〕

The present invention will be further explained below based on Examples.

Example 1 Neutral red was immobilized on a polyester film as a base material using polyacrylamide gel,
A red coloring layer 2a-1-a (R)% was formed in a mosaic pattern as shown in FIG.

Next, methyl green is immobilized on the base material using a polyacrylamide gel in the same manner as the buttering in the coloring layer (2) to form the green coloring layer 2a-2-a (G) in FIG. was formed.

Furthermore, Nile blue was patterned on the base material in the same manner as described above by immobilization using a polyacrylamide gel anchor to form the blue coloring layer 2a-3-a(8) shown in FIG.

Subsequently, the aforementioned 3,4-dihydroretinalized bacteriorhodopsin is laminated on the coloring layer (day) to form the photosensitive layer 2a-
1-b was obtained.

Similarly, 13-cis-retinalized bacteriorhodopsin is used instead of 3,4-dihydroretinalized bacteriorhodopsin, and the photosensitive layer 2a-2-b is placed on the coloring layer (G) and the 3,4-dihydroretinalized bacteriorhodopsin is used. 5,6-dihydroretinal bacteriorhodopsin was used instead of dihydroretinal bacteriorhodopsin to form the photosensitive layer 2a-3-
b were respectively formed on the color forming layer (8) to obtain a recording medium of the present invention.

After moistening the recording medium formed as above with water,
The desired positive color original image (5c) is transparent on the recording layer.
m x 5 cm)%, and white light was irradiated from above for 5 minutes.

Then, a color image corresponding to the original image consisting of the R, G, and B fine mosaic patterns was formed.

[Brief explanation of the drawing]

FIG. 1(A) is a partial plan view of the recording medium of the present invention;
Figure (8) is a partial cross-sectional view taken along the line A-A in Figure 1 (A), Figures 2 and 3 are partial cross-sectional views of other examples of the recording medium of the present invention, and Figure 4 (A ) to (C) are drawings showing the process of light irradiation in the image forming method of the present invention using the recording medium shown in FIG. 3. 1: Base material 2: Recording layer 2a, 2a-1 to 2a-3: Image forming layer 2aa, 2
a-1-a to 2a-3-a: coloring layers 2ab, 2a
-1-b-2a-3-b: Photosensitive layer (A) (B) FIG.

Claims (1)

[Scope of Claims] 1) An image forming unit having a region holding a photosensitive pigment protein and a coloring means that develops color according to a change in the hydrogen ion concentration of the region, the coloring means exhibiting different colors, and 1. A recording medium comprising a recording layer in which one or more combinations of image forming units having different sensitivity wavelengths of photosensitive pigment proteins are mixed for different colors. 2) Claim 1, wherein the photosensitive pigment protein is selected from bacteriorhodopsin and derivatives thereof.
Recording media described in section. 3) A region that retains a photosensitive pigment protein and water: A coloring means that develops color according to a change in hydrogen ion concentration in the region:
A record having a recording layer in which image-forming units having different color-forming means are mixed in such a way that there is one or more combinations of image-forming units with different colors exhibited by the color-forming means and with different photosensitive wavelengths of photosensitive pigment proteins for each different color. A method for forming a color image, comprising the step of irradiating a medium with light having a wavelength corresponding to a color exhibited by an image forming unit according to image information. 4) Claim 3, wherein the photosensitive pigment protein is selected from bacteriorhodopsin and its derivatives.
The image forming method described in Section.