JP2003304890A - Method for producing erasable dye with microorganism, erasable dye produced thereby and erasable ink containing erasable dye - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing an erasable dye with a microorganism, the erasable dye produced by the method and an erasable ink containing the erasable dye. <P>SOLUTION: A microorganism belonging to the genus Streptomyces or Aspergillus and capable of producing a dye erasable by the radiation of visible light and/or ultraviolet light is cultured in a medium and the erasable dye is separated from the cultured product. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing an erasable dye by using a microorganism belonging to actinomycetes and filamentous fungi, an erasable dye by the production method and an erasable dye containing the erasable dye. For inks.

[0002]

2. Description of the Related Art Ink used for printed matter, copied matter, drawing, etc. is required to have a light resistance that can be stored for a long period of time, and an erasable color that can be erased by some method after a certain period of use. They are roughly divided into those that require sex. Generally, used prints, copies, and other papers produced in business establishments are partially recycled as waste papers and then processed into recycled papers, but most of them are incinerated for confidentiality protection. It is desirable that the used paper can be reused without processing, and for that purpose, it is necessary that the printed or copied portion can be erased or erased from the used paper.

Currently, as the dyes used in inks used for printed matter, copied matter, drawing, etc., chemical synthetic dyes are the mainstream, but since synthetic compounds may contain environmental hormones, they adversely affect the environment. There is an increasing need for non-natural pigments. In particular, paper that is repeatedly used with decolorizable ink has many opportunities for humans to directly handle it,
The decolorizable ink used for this purpose is required to be safe for the human body.

[0004] Among microorganisms, those producing red pigments such as red yeast mold are known. In addition, as a decolorizable dye derived from a microorganism to be blended in a decolorizable ink, JP-A-11-806
No. 31 describes a dye produced by a microorganism of the genus Yantinobacterium. The pigment produced by the microorganism of the genus Yantinobacterium has a dark blue to purple blue color tone. However, natural pigments of various hues are required to achieve colorful and beautiful prints or prints.

Therefore, an object of the present invention is to provide a method for producing a decolorizable dye by a microorganism, a decolorizable dye by the production method, and a decolorizable ink containing the decolorizable dye.

[0006]

As a result of earnest research in view of the above object, the present inventors have found that microorganisms belonging to the genus Streptomyces and the genus Aspergillus are excellent in decolorization by irradiation with visible light and / or ultraviolet light. The present invention was conceived, and the present invention was found to produce a pigment showing

That is, the first method for producing a color erasable dye of the present invention is a microorganism belonging to the genus Streptomyces and capable of producing a color erasable dye capable of erasing by irradiation with visible light and / or ultraviolet light. Is cultivated in a medium, and the decolorizable dye is collected from the obtained culture.

[0008] In the first method for producing a decolorizable dye, it is preferable that the culturing is carried out aerobically in a liquid medium. The microorganisms belonging to the genus Streptomyces include Streptomyces sp. Myces SP AJ9575 (FERM P-18809) and Streptomyces SP AJ9576 (FERM P-1881)
0) is preferred.

The second method for producing a decolorizable dye of the present invention is
A microorganism belonging to the genus Aspergillus, which has the ability to produce a decolorizable dye that is decolorized by irradiation with visible light and / or ultraviolet light, is cultured in a medium, and the decolorizable dye is collected from the obtained culture. Characterize.

In the second method for producing a decolorizable dye, it is preferable that the culturing is carried out aerobically in a liquid medium. As the microorganism belonging to the genus Aspergillus, it is preferable to use a microorganism belonging to Aspergillus terreus.

The decolorizable ink of the present invention is characterized by containing a decolorizable dye obtained by the above-mentioned first and / or second method for producing a decolorizable dye. The decolorizable ink of the present invention rapidly fades upon irradiation with visible light and / or ultraviolet light,
Finally, it becomes colorless (decolorized) and is useful as a decolorizable ink for inkjet printers and ink for writing instruments.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION In the present specification, the decoloring property refers to the property of a dye which, when used in an ink composition, rapidly loses its color tone and becomes colorless upon irradiation with a predetermined amount of visible light and / or ultraviolet light. Say.

[1] Method using microorganism belonging to Streptomyces genus As a microorganism (strain) belonging to Streptomyces genus used in the present invention, for example, Streptomyces sp. AJ9573 (FERM P-18807) ,
Streptomyces sp. AJ9574 (FERM P-1880
8), Streptomyces sp. AJ9575 (FERM P-18
809), Streptomyces sp. AJ9576 (FERM P-
18810), etc. (below, unless otherwise specified, Streptomyces sp. AJ9573, AJ9574,
Simply replace the AJ9575 and AJ9576 with the AJ9573, AJ9574, and AJ95, respectively.
75 and AJ9576).

The above-mentioned strains are the Kosugi Town (AJ9573), Toyama Prefecture,
Using each soil sample collected in Kawasaki City, Kanagawa Prefecture (AJ9574, AJ9575 and AJ9576), HV agar medium [humic acid 1.0 g (dissolved in 0.2 N NaOH 10 ml), potassium chloride 1.71 g, hydrogen phosphate] Disodium dodecahydrate 1.5
g, magnesium sulfate heptahydrate 0.05 g, iron (II) sulfate heptahydrate 0.01 g, calcium carbonate 0.02 g, thiamine hydrochloride
0.5 mg, riboflavin 0.5 mg, niacin 0.5 mg, pyridoxine hydrochloride 0.5 mg, inositol 0.5 mg, calcium pantothenate 0.5 mg, p-aminobenzoic acid 0.5 m
g, biotin 0.25 mg, agar 18 g and distilled water 1 L (pH 7.
It consists of 2). HV is a humic acid vitamin
represents n). ], And was isolated by separating the formed colonies.

(A) Bacteriological Properties The bacteriological properties of AJ9573, AJ9574, AJ9575 and AJ9576 will be described. For taxonomic studies of these strains, Shirling and Gott
Method proposed by lieb (International Streptomyces
Project method (ISP): International Journal of S
ystematic Bacteriology vol.16, No.3, p.313-340, (1
966)) and the method proposed by Waksman (Waksman, SA:
Classification, identification and descriptions of
generaand species. The Actinomycetes Vol. II, Wil
liams & Wilkins, Baltimore (1961)) was adopted. As the medium, the above ISP-defined medium and the above Actinomycetes v
It observed at 27 degreeC for 3 weeks using the culture medium of ol.II. The color tone is described according to the New Colors Encyclopedia edited by Japan Color Research Institute (issued by Nippon Color Research Institute Co., Ltd. in 1987).

(1) Mycological properties of AJ9573 Morphological properties Basal hyphae were elongated and well branched, but were not fragmented. Aerial aerial hyphae settled on starch mineral salt medium (ISP No. 4) and nutrient agar medium, and when matured, formed 30 to 50 spore chains at the tip. The spore linkage was spiral, but no formation of ring silk was observed. No sporangia and motile spores were observed. The spores were spherical to oval in shape and the size was 0.5 to 0.7 × 0.5 to 0.7 μm.

Cultural Properties Table 1 shows the observation results of each medium after culturing at 27 ° C. for 2 weeks. The colony color was gray. The underside of the basal hypha showed a yellow color. No formation of a dye exhibiting solubility in the medium (soluble dye) was observed.

[0018]

[Table 1]

Physiological properties The growth temperature range was 8 to 42 ° C. No formation of melanin-like pigment was observed on tyrosine agar medium (ISP No. 7). Regarding carbon source availability, Gottlieb and Pridham's basal medium (ISP No. 9) was cultured at 27 ° C for 2 weeks and observed. As a result, L-arabinose, D-xylose, D-glucose, D-fructose, L -Rhamnose, inositol and D-mannitol were used.

Chemotaxonomic properties Analysis of cell wall amino acid composition was performed by Lechealier and Stanech.
Et al. (Actinomycetales, Ed., H. PRAUSER, pp. 39
3 ~ 405. Jena, Gustav Fischer Verlag, (1970), STA
NECK, JL & GD ROBERTS: Simplified approach
to identification of aerobic actinomycetes by thin
-layer chromatography. Appl. Microbiol. 28: 226 ~
231, (1974)), LL-diaminopimelic acid and glycine were detected.

(2) Mycological properties of AJ9574 Morphological properties Basal hyphae were elongated and well branched, but were not fragmented. Aerial mycelia grow on yeast malt medium (ISP No. 2), starch inorganic salt medium (ISP No. 4) and nutrient agar medium,
When matured, 10 to 20 spore chains were formed at the tip. The spore linkage was straight. No sporangia and motile spores were observed. Spores are cylindrical and their size is 0.4
〜0.5 × 1.0〜1.5μm。

Cultural Properties Table 2 shows the observation results of each medium after culturing at 27 ° C. for 2 weeks. The colony color of the flora was white to light brown. The back side of the basal hypha showed brown to blue. Formation of soluble pigment was observed.

[0023]

[Table 2]

Physiological Properties The growth temperature range was 10-44 ° C. The formation of melanin-like pigment is slightly observed on tyrosine agar medium (ISP No. 7). The carbon source availability was examined by the same method as for AJ9573. As a result, L-arabinose, D-xylose, D-
Glucose, D-fructose and L-rhamnose were used.

Chemotaxonomic properties Regarding the amino acid composition of the cell wall, Lechealier and St.
As a result of analysis according to the method of anech et al., LL-diaminopimelic acid and glycine were detected.

(3) Mycological properties of AJ9575 Morphological properties Basal hyphae were elongated and well branched, but were not fragmented. Aerial mycelium grows on tyrosine agar medium (ISP No.7) and glucose asparagine medium, and when matured, it becomes 30 at the tip.
~ 50 spore chains were formed. The spore linkage was spiral, but no formation of ring silk was observed. No sporangia and motile spores were observed. The spores were oval to cylindrical and the size was 0.5 to 0.7 × 1.2 to 1.4 μm.

Cultural Properties Table 3 shows the observation results of each medium after culturing at 27 ° C. for 2 weeks. The colony color of the colony was white to gray. The back of the basal hypha showed a greenish gray color. Formation of soluble pigment was observed.

[0028]

[Table 3]

Physiological properties The growth temperature range was 8 to 42 ° C. No formation of melanin-like pigment was observed on tyrosine agar medium (ISP No. 7). The carbon source availability was examined by the same method as in AJ9573. As a result, L-arabinose, D-xylose, D-glucose, D-fructose, sucrose, L-rhamnose and D-mannitol were used.

Chemotaxonomic properties Regarding the amino acid composition of the cell wall, Lechealier and St.
As a result of analysis according to the method of anech et al., LL-diaminopimelic acid and glycine were detected.

(4) Mycological properties of AJ9576: Morphological properties Basal hyphae were elongated and well branched, but were not fragmented. Aerial mycelia are yeast malt medium (ISP No.2), oatmeal medium (ISP No.3), starch inorganic salt medium (ISP No.2).
4), and 3 on the tip when it grows and matures on nutrient agar.
0-50 spore chains were formed. The spore linkage was spiral in shape. No sporangia and motile spores were observed. Spores are spherical to oval and their size is 0.5 to 0.7 ×
It was 0.5 to 0.7 μm.

Cultural Properties Table 4 shows the observation results of each medium after culturing at 27 ° C. for 2 weeks. The colony color was gray. The back side of the basal hyphae was brown. The formation of soluble pigment was slightly observed.

[0033]

[Table 4]

Physiological properties The growth temperature range was 10-44 ° C. A slight formation of melanin-like pigment was observed on tyrosine agar medium (ISP No. 7). The carbon source availability was examined by the same method as in AJ9573. As a result, L-arabinose, D-xylose, D-glucose, D-fructose, L-rhamnose, inositol and D-mannitol were used.

Chemotaxonomic properties Regarding the amino acid composition of the cell wall, Lechealier and St.
As a result of analysis according to the method of anech et al., LL-diaminopimelic acid and glycine were detected.

Based on the above properties, Stanley Tea
Williams ed., Vergie's Manual of Systematic Bacteriology Volume 4 (Berg
ey's Manual of Systematic Bacteriology, Vol.4) (198
As a result of the search according to (4 years), it was found that all of the above strains belong to the genus Streptomyces. Therefore, these microorganisms were treated with Streptomyces sp. AJ9573, Streptomyces sp. AJ9574, Streptomyces sp. AJ9575,
And Streptomyces sp. AJ9576.
AJ9573, AJ9574, AJ9575 and AJ9576 are the accession numbers FERM P-18807, FERM P-18808, FERM P-18809 and FERM, respectively.
It has been deposited with the National Institute of Advanced Industrial Science and Technology as P-18810 (deposit date: April 8, 2002).

(B) Culturing Method For culturing each of the above-mentioned microorganisms, an ordinary liquid medium used for culturing actinomycetes or filamentous fungi can be used. For example, it contains sugars such as glucose, sucrose, and starch hydrolysates as carbon sources, and organic nitrogen sources such as peptone, soybean protein, oatmeal powder, and rapeseed powder as nitrogen sources, as well as salt, phosphate, and sulfuric acid. Examples of the liquid medium include inorganic compounds such as salts and other vitamins and micronutrients such as yeast extract that are added as necessary.

The culture is carried out by inoculating each of the above-mentioned microorganisms into the above liquid medium and aerobically under a neutral or slightly acidic condition at a temperature of 20 to 32 ° C. for 3 to 7 days. If the pH drops during culture, neutralize with alkali or add calcium carbonate or the like to the medium in advance.

By the above-mentioned culture method, a water-soluble dye is generally obtained from AJ9573, a water-soluble and fat-soluble dye is obtained from AJ9574, and a fat-soluble dye is obtained from AJ9575 and AJ9576. The water-soluble dye produced by AJ9573 appears yellow regardless of pH when its aqueous solution is prepared. AJ9574
When the aqueous solution is prepared, the water-soluble dye produced by (1) exhibits red in the acidic region and purple in the neutral to alkaline region. The lipophilic dye produced by AJ9574 exhibits a purple color when its organic solution is prepared. The fat-soluble pigment produced by AJ9575 exhibits a purple color when its organic solution is prepared.
The fat-soluble dye produced by AJ9576 turns green when its organic solution is prepared.

With respect to the water-soluble dye, a powdery substance can be collected by centrifuging or filtering the obtained culture and appropriately concentrating the obtained supernatant. Regarding the fat-soluble dye, a powdery substance can be collected by adding an organic solvent such as butanol to the obtained culture, performing appropriate extraction, and concentrating the extract. When these powdery dyes are further purified, the target dye fraction may be collected by a gel filtration method or the like.

(C) Decolorizable dye Any aqueous solution or organic solution containing a dye obtained by the above method is rapidly faded by irradiation with visible light and / or ultraviolet light, and finally becomes colorless (discolored). The type of visible light and ultraviolet light may be sunlight or artificial light (such as a fluorescent lamp). Although the intensity of visible light or ultraviolet light has a great influence on decoloring, for example, any dye is dissolved in water or alcohol and left at 25 ° C for 40 hours under a daylight fluorescent lamp (2500 lux). In that case, the absorbance at each wavelength is reduced to 70% or less. The disappearance time can be adjusted by selecting the intensity of visible light and / or ultraviolet light. Further, when performing the erasing process in an extremely short time, a dedicated light irradiation device can be used.

The pigment produced by the microorganism of the genus Streptomyces is safe to the human body when used, and has high harmony with the environment.

As is well known, actinomycetes are liable to cause mutation not only by artificial manipulation (for example, ultraviolet irradiation, irradiation, chemical treatment, etc.) but also in nature.
AJ9573, AJ9574, AJ9575 and AJ9576 are the same in this respect. In the present specification, AJ9573, AJ9574, AJ9575 and AJ95
Each 76 includes all of the mutants.

Among these mutants are genetic methods,
For example, those obtained by recombination, transduction, transformation, etc. are also included. That is, AJ9573, which produces a decolorizable dye,
AJ9574, AJ9575 and AJ9576 and mutants thereof, and strains not clearly distinguished from these are all AJ9573,
It is included in each of AJ9574, AJ9575 and AJ9576.

[2] Method using microorganisms belonging to the genus Aspergillus The microorganisms (strains) belonging to the genus Aspergillus used in the present invention include Aspergillus terreus.
Preferred are those belonging to Aspergillus terreus), such as Aspergillus terreus (IFO-8835: Catalog Number of Fermentation Research Institute).

This microorganism can be cultivated and collected by the same method as the microorganism belonging to Streptomyces. Both water-soluble dyes and fat-soluble dyes are generally obtained from microorganisms belonging to Aspergillus terreus. The water-soluble dye exhibits brown color when its aqueous solution is prepared, and the fat-soluble dye exhibits ocher color when its organic solution is prepared.

Aqueous solutions and organic solutions containing this dye also rapidly fade upon irradiation with visible light and / or ultraviolet light, and finally become colorless (discolored). The decolorizing property is similar to that of the pigment produced by Streptomyces microorganisms. The pigment produced by a microorganism belonging to the genus Aspergillus is safe for the human body when used, and has high harmony with the environment.

[3] Decolorable ink Since each of the above dyes has excellent decolorability, it can be used as a decolorable ink for printing, copying and drawing. Specifically, by dissolving or dispersing each of the above dyes in an appropriate organic solvent or water, it can be used as an ink for inkjet printers and an ink for writing instruments. As the organic solvent, known ones used for inks for inkjet printers and inks for writing instruments can be used. Specific examples include alcohols, glycols, glycol ethers, fatty acid esters, ketones, ethers, hydrocarbon solvents, polar solvents and the like. Water may be added as long as the organic solvent is water-soluble.

As the organic solvent, alcohol and glycol are preferable. As alcohol, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutyl alcohol and t
-Butyl alcohol can be mentioned.

As the glycol, ethylene glycol,
Mention may be made of diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, butylene glycol, hexanediol, pentanediol, glycerin, hexanetriol and thiodiglycol.

These organic solvents may be used alone or in combination of two or more kinds. Examples include combinations of alcohols and / or glycols with polar solvents. As the polar solvent, 2-pyrrolidone, formamide, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, sulfolane, N-methyl-2-pyrrolidone, N-vinyl-2-pyrrolidone, 2-oxazolidone, Mention may be made of 1,3-dimethyl-2-imidazolidinone, acetonitrile and acetone.

Each of the above dyes may be dissolved in water or an organic solvent, and if necessary, various dispersing machines (for example, ball mill,
Use a sand mill, attritor, roll mill, agitator mill, Henschel mixer, colloid mill, ultrasonic homogenizer, pearl mill, jet mill, ong mill, etc. to make fine particles, and then use a suitable dispersant (surfactant).
May be used for dispersion.

If necessary, a binder and pH may be added to the decolorizable ink.
An adjusting agent, a viscosity adjusting agent, a penetrating agent, a surface tension adjusting agent, an antioxidant, an antiseptic agent, an antifungal agent and the like can be added.

The content of each of the above dyes is preferably 0.01 to 90% by weight based on the total weight of the decolorizable ink composition,
It is more preferably 0.5 to 15% by weight. As a result, good printing characteristics can be obtained.

[0055]

The present invention will be described in more detail by the following examples, but the present invention is not limited to these examples.

Example 1 25 g sucrose, 3 g polypeptone, 10 g oatmeal powder and rape seed meal (Rape see
After dissolving 10 g of d meal) in 1 L of distilled water, the pH was adjusted to 7.0 with calcium carbonate to prepare a liquid medium for culturing actinomycetes.
The obtained liquid medium was placed in four 300 ml Erlenmeyer flasks each sterilized by 40 ml, and heat sterilized at 120 ° C. for 10 minutes. Then, using the four obtained media, Streptomyces sp. AJ9573, AJ9574, AJ9575 and AJ9576
Prepare the culture solution of each strain of (inoculation amount: 1 platinum loop), and
Shaking culture (180 rpm) was carried out on a rotary shaker at 5 ° C for 5 days.

Glucose 25 g, Essan meat 10 g, S-
A liquid medium for filamentous fungus culture after dissolving 10 g of GR (malt fermentation organic, manufactured by Nishinippon Kosan Co., Ltd.) and 2 g of sodium chloride in 1 L of distilled water, and then adding 3 g of calcium carbonate to adjust the pH to 6.5. Was prepared. 40 ml of the obtained liquid medium was placed in a sterilized 300 ml Erlenmeyer flask and heat-sterilized at 120 ° C. for 10 minutes. Next, one platinum loop of Aspergillus terreus IFO-8835 (hereinafter referred to as IFO-8835 unless otherwise specified) was inoculated into the medium at 25 ° C.
Culture for 5 days on a rotary shaker (18
0 rpm).

Obtained AJ9573, AJ9574, AJ9575 and AJ95
An equal amount of butanol was added to the culture of 76 and the culture of IFO-8835 to separate into a water-soluble fraction and a butanol fraction to obtain each dye solution (dye concentration: 0.01 to 0.1 mg / ml). 20 each dye solution
Dispense 0 μL each to a microplate (NUNK) and use Benc
Absorbance at wavelengths of 340, 405, 550, 570, 595 and 630 nm was measured using an hmark microplate reader (Biorad). The results are shown in Table 5.

Next, each dye solution was put in a glass screw cap bottle,
A bright place sample was prepared by irradiation with a fluorescent lamp (2500 lux) at 25 ° C for 40 hours. On the other hand, each dye solution was put in a glass screw cap bottle and covered with aluminum foil at 25 ° C. for 40 hours to prepare a dark sample in which light was shielded. The absorbance at each wavelength was measured in the same manner as above for each of the obtained light and dark samples. As a result, no change in absorbance was observed in the dark sample. Therefore, the following formula: E ＝
(Absorbance of light sample) / (Absorbance of dark sample)
The E value was calculated by. The smaller the E value, the higher the decoloring property. The obtained results are shown in Table 6.

Comparative Example 1 Decolorizable pigment produced by the genus Yantinobacterium (KK-217 strain pigment, produced according to the method described in Japanese Examined Patent Publication No. 4-6347).
(Purple) dissolved in ethanol, commercial ink [J ink JK-630 (yellow, manufactured by Actics Okamoto), J ink JK-620 (red, manufactured by Actics Okamoto), J ink JK-610 (blue, manufactured by Actics Okamoto Co., Ltd.), and IJR-CA-03 (black, refilled ink for Union Printer made by Union Chemica Co., Ltd.)] were diluted with water to prepare a pigment liquid (pigment). The density was the same as in Example 1), and the decoloring property was examined in the same manner as in Example 1. The results are shown in Tables 5 and 6.

[0061]

[Table 5]

[0062]

[Table 6]

As is clear from Table 6, AJ9573 and AJ957
4, the dye solution containing the dyes derived from AJ9575, AJ9576 and IFO-8835 exhibited faster decoloring properties than the dye solution of Comparative Example 1. Regarding the pigment liquid containing water-soluble pigment,
The dye solution containing dyes derived from AJ9573 is yellow and IFO8
The pigment liquid containing the pigment derived from 835 was brown and showed decoloring property. In addition, the dye solution containing the water-soluble dye No.AJ48
It showed a purple color in the neutral and alkaline regions and a red color in the acidic region and showed decoloring properties at any pH.

Example 2 (Printing Experiment) As in Example 1, AJ9574, AJ9575 and IFO-
After the dye solution of 8835 was prepared, it was concentrated in a vacuum dryer, and the [absorbance at the wavelength at which each dye shows the maximum peak (× 1)]
The density was adjusted so that x [printing liquid amount (μL)] = 300 to 400 (ie, the absorbance at a wavelength of 570 nm was applied to AJ9574, and the wavelength was applied to AJ9575 and IFO-8835.
The absorbance at 340 nm was applied). White fine PPC paper (manufactured by Fuji Xerox Co., Ltd.) using each of the obtained dye solutions
Was spot-printed (coated in a circle with a diameter of 1 cm). Each of the obtained prints was left at 25 ° C under irradiation of a fluorescent lamp (2500 lux) and the color disappeared over time (0
Observed for ~ 20 days). The degree of residual dye was determined by visually observing the color strength. The results are shown in Table 7.

Comparative Example 2 Similar to Comparative Example 1, a decolorizable dye (KK-217 strain dye) produced by the genus Yantinobacterium and a dye solution of a commercially available ink were prepared and then concentrated in a vacuum drier. The concentration was adjusted so that the absorbance at each wavelength at which each dye shows the maximum peak (× 1)] × [printing liquid amount (μL)] = 300 to 400 (ie, the absorbance at a wavelength of 570 nm for the KK-217 strain dye was Applied, the absorbance at a wavelength of 405 nm for JK-630, the absorbance at a wavelength of 550 nm for JK-620, the absorbance at a wavelength of 340 nm for JK-610, the wavelength for IJR-CA-03. The absorbance at 570 nm was applied). Example 2 using each of the obtained dye solutions
A printing experiment was conducted in the same manner as in. The results are shown in Table 7.

As is clear from Table 7, the dye solution containing the dyes derived from AJ9574, AJ9575 and IFO-8835 was confirmed to be more easily decolored than the dye solution of Comparative Example 2.

[0067]

[Table 7]

Example 3 (ink for inkjet printer) AJ9574, AJ9575 and IFO-8835 were respectively cultured in the same manner as in Example 1. An equal amount of butanol was added to each culture to separate the water-soluble fraction and the butanol fraction.The water-soluble fraction for AJ9574 and the butanol fraction for AJ9575 and IFO-8835 were centrifuged to separate the supernatant. After that, each dye was collected by concentrating to dryness with a vacuum dryer. The resulting water-soluble dye of AJ9574 is dissolved in distilled water, the fat-soluble dye of AJ9575 and IFO-8835 is dissolved in butanol, and the absorbance is 0.2 at the wavelength having the maximum peak when diluted 1/1000. Were prepared respectively.
After adding 5 parts by weight of diethylene glycol and 5 parts by weight of propanol to 90 parts by weight of each of the obtained dye solutions, 0.45 μm
Then, three types of inks for inkjet printers were prepared. Each of the obtained inks for inkjet printers was used to print on high quality PPC paper (manufactured by Fuji Xerox Co., Ltd.) by an inkjet printer (BBJC-600J manufactured by Canon Inc.). After printing, each paper was allowed to stand still at 25 ° C under a daylight fluorescent lamp (2500 lux) and the fading property of the print was observed. After 40 hours, the print disappeared.
On the other hand, when each similarly printed sheet was allowed to stand in a dark place (1 lux or less), there was no change in printing.

Example 4 (Ink for Writing Instruments) A dye solution derived from AJ9574, AJ9575 and IFO-8835 was prepared in the same manner as in Example 3, and 15 parts by weight of ethylene glycol and 5 parts by weight of 2-pyrrolidone were added to 80 parts by weight of each dye solution. After adding 1 part, the mixture was filtered through a 0.45 μm filter to prepare three types of writing instrument inks. A marking pen filled with each of the obtained inks for writing instruments was prepared and drawn on a white high-quality PPC paper (manufactured by Fuji Xerox Co., Ltd.) using three types of marking pens. After the drawing, each paper was left at 25 ° C under daylight fluorescent lamp (2500 lux) and observed its fading property. After 40 hours, the drawing disappeared. On the other hand, when each of the similarly drawn sheets was placed in a dark place (1 lux or less), there was no change in the drawing.

[0070]

As described above, by using the decolorizable dye produced by the method of the present invention, the print is preserved / maintained as long as it is shielded from visible rays and ultraviolet rays, but the print is Visible light and // when no longer needed
Alternatively, it is possible to provide a decolorizable ink that can be rapidly decolorized by irradiation with ultraviolet rays. Therefore, it is useful for recycling papers. Furthermore, since the decolorizable ink of the present invention contains a natural pigment, it is safe for the human body and has high harmony with the environment.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C12R 1: 465) C12R 1:66 (C12P 1/02 C12R 1:66) (C12P 1/06 C12R 1: 465) (C12P 1/06 C12R 1:66) (72) Inventor Naoko Tsuyoshi 1-1 1-1 Suzuki-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Ajinomoto Co., Inc. Life Science Research Institute (72) Ryosuke Fudo Kanagawa 1-1, Suzuki-cho, Kawasaki-ku, Kawasaki-shi Ajinomoto Co., Inc. Life Science Institute (72) Inventor Takayuki Kajiura 1-1, Suzuki-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Ajinomoto Co., Inc. F-term (Reference) ) 4B064 AH19 CA03 CA05 CD09 CD20 DA16 4J039 BB00 BE01 BE02 EA21 EA29 GA24 GA26

Claims (15)

[Claims] 1. A microorganism belonging to the genus Streptomyces and capable of producing an erasable dye capable of erasing by irradiation with visible light and / or ultraviolet light is cultured in a medium, and the erasable color is obtained from the obtained culture. A method for producing a decolorizable dye, which comprises collecting a decolorizable dye. 2. The method for producing a decolorizable dye according to claim 1, wherein the microorganism belonging to the genus Streptomyces is Streptomyces sp. AJ9573 (FERM P-188.
07) A method for producing a decolorizable dye, characterized in that 3. The method for producing a decolorizable dye according to claim 1, wherein the microorganism belonging to the genus Streptomyces is Streptomyces sp. AJ9574 (FERM P-188.
A method for producing a decolorizable dye, which comprises using (08). 4. The method for producing a decolorizable dye according to claim 1, wherein the microorganism belonging to the genus Streptomyces is Streptomyces sp. AJ9575 (FERM P-188.
09) The method for producing a decolorizable dye, characterized in that 5. The method for producing a decolorizable dye according to claim 1, wherein the microorganism belonging to the genus Streptomyces is Streptomyces sp. AJ9576 (FERM P-188.
10. A method for producing a decolorizable dye, which comprises using 10). 6. A decolorizable dye obtained by the production method according to claim 2, wherein the decolorizable dye is water-soluble and its aqueous solution exhibits a yellow color tone. 7. A decolorizable dye obtained by the production method according to claim 3, which is water-soluble and whose aqueous solution exhibits a red to purple color tone. 8. A decolorizable dye obtained by the production method according to claim 3, wherein the decolorizable dye is fat-soluble and the organic solution thereof exhibits a purple color tone. 9. A decolorizable dye obtained by the method according to claim 4, wherein the decolorizable dye is fat-soluble and its organic solution exhibits a purple color tone. 10. A decolorizable dye obtained by the production method according to claim 5, which is fat-soluble and whose organic solution exhibits a green color tone. 11. A microorganism belonging to the genus Aspergillus and having the ability to produce a decolorizable dye that is decolorized by irradiation with visible light and / or ultraviolet light is cultured in a medium, and the decolorizable dye is obtained from the obtained culture. A method for producing a decolorizable dye, which comprises: 12. The method for producing a decolorizable dye according to claim 11, wherein a microorganism belonging to Aspergillus terreus is used as the microorganism belonging to the genus Aspergillus. 13. A decolorizable dye obtained by the production method according to claim 11 or 12, which is water-soluble,
An erasable dye characterized in that the aqueous solution exhibits a brown color tone. 14. A decolorizable dye obtained by the production method according to claim 11 or 12, which is fat-soluble,
An erasable dye, characterized in that the organic solution exhibits an ocher color tone. 15. An erasable ink comprising the erasable dye obtained by the method according to claim 1, 2, 3, 4, 5, 11, or 12.